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Articles on Scientific research

Displaying 1 - 20 of 88 articles.

Early COVID-19 research is riddled with poor methods and low-quality results − a problem for science the pandemic worsened but didn’t create

Dennis M. Gorman , Texas A&M University

Netflix’s You Are What You Eat uses a twin study. Here’s why studying twins is so important for science

Nathan Kettlewell , University of Technology Sydney

Fact-bombing by experts doesn’t change hearts and minds. But good science communication can

Tom Carruthers , The University of Western Australia ; Heather Bray , The University of Western Australia , and Matthew Nurse , Australian National University

Talking about science and technology has positive impacts on research and society

Ashley Rose Mehlenbacher , University of Waterloo ; Donna Strickland , University of Waterloo , and Mary Wells , University of Waterloo

Tenacious curiosity in the lab can lead to a Nobel Prize – mRNA research exemplifies the unpredictable value of basic scientific research

André O. Hudson , Rochester Institute of Technology

Pigs with human brain cells and biological chips: how lab-grown hybrid lifeforms bamboozle scientific ethics

Julian Koplin , Monash University

When Greenland was green: Ancient soil from beneath a mile of ice offers warnings for the future

Paul Bierman , University of Vermont and Tammy Rittenour , Utah State University

10 reasons humans kill animals – and why we can’t avoid it

Benjamin Allen , University of Southern Queensland

Hurricanes push heat deeper into the ocean than scientists realized, boosting long-term ocean warming, new research shows

Noel Gutiérrez Brizuela , University of California, San Diego and Sally Warner , Brandeis University

Colonialism has shaped scientific plant collections around the world – here’s why that matters

Daniel Park , Purdue University

You shed DNA everywhere you go – trace samples in the water, sand and air are enough to identify who you are, raising ethical questions about privacy

Jenny Whilde , University of Florida and Jessica Alice Farrell , University of Florida

Nigeria needs to take science more seriously - an agenda for the new president

Oyewale Tomori , Nigerian Academy of Science

Two decades of stagnant funding have rendered Canada uncompetitive in biomedical research. Here’s why it matters, and how to fix it.

Stephen L Archer , Queen's University, Ontario

How tracking technology is transforming our understanding of animal behaviour

Louise Gentle , Nottingham Trent University

What the world would lose with the demise of Twitter: Valuable eyewitness accounts and raw data on human behavior, as well as a habitat for trolls

Anjana Susarla , Michigan State University

There are 8 years left to meet the UN Sustainable Development Goals, but is it enough time?

Rees Kassen , L’Université d’Ottawa/University of Ottawa and Ruth Morgan , UCL

‘Gain of function’ research can create experimental viruses. In light of COVID, it should be more strictly regulated – or banned

Colin D. Butler , Australian National University

By fact-checking Thoreau’s observations at Walden Pond, we showed how old diaries and specimens can inform modern research

Tara K. Miller , Boston University ; Abe Miller-Rushing , National Park Service , and Richard B. Primack , Boston University

New ‘ethics guidance’ for top science journals aims to root out harmful research – but can it succeed?

Cordelia Fine , The University of Melbourne

Expanding Alzheimer’s research with primates could overcome the problem with treatments that show promise in mice but don’t help humans

Agnès Lacreuse , UMass Amherst ; Allyson J. Bennett , University of Wisconsin-Madison , and Amanda M. Dettmer , Yale University

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Calorie restriction study reveals complexities in how diet impacts aging

Penn State researchers may have uncovered another layer of complexity in the mystery of how diet impacts aging. A new study led by researchers in the Penn State College of Health and Human Development examined how a person's telomeres -- sections of genetic bases that function like protective caps at the ends of chromosomes -- were affected by caloric restriction.

The team published their results in Aging Cell . Analyzing data from a two-year study of caloric restriction in humans, the researchers found that people who restricted their calories lost telomeres at different rates than the control group -- even though both groups ended the study with telomeres of roughly the same length. Restricting calories by 20% to 60% has been shown to promote longer life in many animals, according to previous research.

Over the course of human life, every time a person's cells replicate, some telomeres are lost when chromosomes are copied to the new cell. When this happens, the overall length of the cell's telomeres becomes shorter. After cells replicate enough times, the protective cap of telomeres completely dissipates. Then, the genetic information in the chromosome can become damaged, preventing future reproduction or proper function of the cell. A cell with longer telomeres is functionally younger than a cell with short telomeres, meaning that two people with the same chronological age could have different biological ages depending on the length of their telomeres.

Typical aging, stress, illness, genetics, diet and more can all influence how often cells replicate and how much length the telomeres retain, according to Idan Shalev, associate professor of biobehavioral health at Penn State. Shalev led the researchers who analyzed genetic samples from the national CALERIE study -- the first randomized clinical trial of calorie restriction in humans. Shalev and his team sought to understand the effect of caloric restriction on telomere length in people. Because telomere length reflects how quickly or slowly a person's cells are aging, examining telomere length could allow scientists to identify one way in which caloric restriction may slow aging in humans.

"There are many reasons why caloric restriction may extend human lifespans, and the topic is still being studied," said Waylon Hastings, who earned his doctorate in biobehavioral health at Penn State in 2020 and was lead author of this study. "One primary mechanism through which life is extended relates to metabolism in a cell. When energy is consumed within a cell, waste products from that process cause oxidative stress that can damage DNA and otherwise break down the cell. When a person's cells consume less energy due to caloric restriction, however, there are fewer waste products, and the cell does not break down as quickly."

The researchers tested the telomere length of 175 research participants using data from the start of the CALERIE study, one year into the study and the end of the study after 24 months of caloric restriction. Approximately two-thirds of study participants participated in caloric restriction, while one-third served as a control group.

During the study, results showed that telomere loss changed trajectories. Over the first year, participants who were restricting caloric intake lost weight, and they lost telomeres more rapidly than the control group. After a year, the weight of participants on caloric restriction was stabilized, and caloric restriction continued for another year. During the second year of the study, participants on caloric restriction lost telomeres more slowly than the control group. At the end of two years, the two groups had converged, and the telomere lengths of the two groups was not statistically different.

"This research shows the complexity of how caloric restriction affects telomere loss," Shalev said. "We hypothesized that telomere loss would be slower among people on caloric restriction. Instead, we found that people on caloric restriction lost telomeres more rapidly at first and then more slowly after their weight stabilized."

Shalev said the results raised a lot of important questions. For example, what would have happened to telomere length if data had been collected for another year? Study participants are scheduled for data collection at a 10-year follow-up, and Shalev said that he was eager to analyze those data when they become available.

Despite the ambiguity of the results, Shalev said there is promise for the potential health benefits of caloric restriction in humans. Previous research on the CALERIE data has demonstrated that caloric restriction may help reduce harmful cholesterol and lower blood pressure. For telomeres, the two-year timeline was not sufficient to show benefits, but those may still be revealed, according to Shalev and Hastings.

Three of Shalev's trainees, Hastings, current graduate student Qiaofeng Ye and former postdoctoral scholar Sarah Wolf, led the research under Shalev's guidance.

Hastings said the opportunity to lead this study was critical to his career.

"I was recently hired as an assistant professor in the Department of Nutrition at Texas A&M University, and I will begin that work in the fall semester," Hastings said. "Prior to this project, I had limited experience in nutrition. This project literally set the course of my career, and I am grateful to Dr. Shalev for trusting me with that responsibility."

Calen Ryan and Daniel Belsky of Columbia University Mailman School of Public Health, Sai Krupa Das of Tufts University, Kim Huffman and William Kraus of Duke University School of Medicine, Michael Kobor and Julia MacIsaac of University of British Columbia, Corby Martin and Leanne Redman of Pennington Biomedical Research Center and Susan Racette of Arizona State University College of Health Solutions all contributed to this research.

The National Institute on Aging funded this research.

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Story Source:

Materials provided by Penn State . Original written by Aaron Wagner. Note: Content may be edited for style and length.

Journal Reference :

• Waylon J. Hastings, Qiaofeng Ye, Sarah E. Wolf, Calen P. Ryan, Sai Krupa Das, Kim M. Huffman, Michael S. Kobor, William E. Kraus, Julia L. MacIsaac, Corby K. Martin, Susan B. Racette, Leanne M. Redman, Daniel W. Belsky, Idan Shalev. Effect of long‐term caloric restriction on telomere length in healthy adults: CALERIE™ 2 trial analysis . Aging Cell , 2024; DOI: 10.1111/acel.14149

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What is Scientific Research and How Can it be Done?

Scientific researches are studies that should be systematically planned before performing them. In this review, classification and description of scientific studies, planning stage randomisation and bias are explained.

Research conducted for the purpose of contributing towards science by the systematic collection, interpretation and evaluation of data and that, too, in a planned manner is called scientific research: a researcher is the one who conducts this research. The results obtained from a small group through scientific studies are socialised, and new information is revealed with respect to diagnosis, treatment and reliability of applications. The purpose of this review is to provide information about the definition, classification and methodology of scientific research.

Before beginning the scientific research, the researcher should determine the subject, do planning and specify the methodology. In the Declaration of Helsinki, it is stated that ‘the primary purpose of medical researches on volunteers is to understand the reasons, development and effects of diseases and develop protective, diagnostic and therapeutic interventions (method, operation and therapies). Even the best proven interventions should be evaluated continuously by investigations with regard to reliability, effectiveness, efficiency, accessibility and quality’ ( 1 ).

The questions, methods of response to questions and difficulties in scientific research may vary, but the design and structure are generally the same ( 2 ).

Classification of Scientific Research

Scientific research can be classified in several ways. Classification can be made according to the data collection techniques based on causality, relationship with time and the medium through which they are applied.

• Observational
• Experimental
• Descriptive
• Retrospective
• Prospective
• Cross-sectional
• Social descriptive research ( 3 )

Another method is to classify the research according to its descriptive or analytical features. This review is written according to this classification method.

I. Descriptive research

• Case series
• Surveillance studies

II. Analytical research

• Observational studies: cohort, case control and cross- sectional research
• Interventional research: quasi-experimental and clinical research
• Case Report: it is the most common type of descriptive study. It is the examination of a single case having a different quality in the society, e.g. conducting general anaesthesia in a pregnant patient with mucopolysaccharidosis.
• Case Series: it is the description of repetitive cases having common features. For instance; case series involving interscapular pain related to neuraxial labour analgesia. Interestingly, malignant hyperthermia cases are not accepted as case series since they are rarely seen during historical development.
• Surveillance Studies: these are the results obtained from the databases that follow and record a health problem for a certain time, e.g. the surveillance of cross-infections during anaesthesia in the intensive care unit.

Moreover, some studies may be experimental. After the researcher intervenes, the researcher waits for the result, observes and obtains data. Experimental studies are, more often, in the form of clinical trials or laboratory animal trials ( 2 ).

Analytical observational research can be classified as cohort, case-control and cross-sectional studies.

Firstly, the participants are controlled with regard to the disease under investigation. Patients are excluded from the study. Healthy participants are evaluated with regard to the exposure to the effect. Then, the group (cohort) is followed-up for a sufficient period of time with respect to the occurrence of disease, and the progress of disease is studied. The risk of the healthy participants getting sick is considered an incident. In cohort studies, the risk of disease between the groups exposed and not exposed to the effect is calculated and rated. This rate is called relative risk. Relative risk indicates the strength of exposure to the effect on the disease.

Cohort research may be observational and experimental. The follow-up of patients prospectively is called a prospective cohort study . The results are obtained after the research starts. The researcher’s following-up of cohort subjects from a certain point towards the past is called a retrospective cohort study . Prospective cohort studies are more valuable than retrospective cohort studies: this is because in the former, the researcher observes and records the data. The researcher plans the study before the research and determines what data will be used. On the other hand, in retrospective studies, the research is made on recorded data: no new data can be added.

In fact, retrospective and prospective studies are not observational. They determine the relationship between the date on which the researcher has begun the study and the disease development period. The most critical disadvantage of this type of research is that if the follow-up period is long, participants may leave the study at their own behest or due to physical conditions. Cohort studies that begin after exposure and before disease development are called ambidirectional studies . Public healthcare studies generally fall within this group, e.g. lung cancer development in smokers.

• Case-Control Studies: these studies are retrospective cohort studies. They examine the cause and effect relationship from the effect to the cause. The detection or determination of data depends on the information recorded in the past. The researcher has no control over the data ( 2 ).

Cross-sectional studies are advantageous since they can be concluded relatively quickly. It may be difficult to obtain a reliable result from such studies for rare diseases ( 2 ).

Cross-sectional studies are characterised by timing. In such studies, the exposure and result are simultaneously evaluated. While cross-sectional studies are restrictedly used in studies involving anaesthesia (since the process of exposure is limited), they can be used in studies conducted in intensive care units.

• Quasi-Experimental Research: they are conducted in cases in which a quick result is requested and the participants or research areas cannot be randomised, e.g. giving hand-wash training and comparing the frequency of nosocomial infections before and after hand wash.
• Clinical Research: they are prospective studies carried out with a control group for the purpose of comparing the effect and value of an intervention in a clinical case. Clinical study and research have the same meaning. Drugs, invasive interventions, medical devices and operations, diets, physical therapy and diagnostic tools are relevant in this context ( 6 ).

Clinical studies are conducted by a responsible researcher, generally a physician. In the research team, there may be other healthcare staff besides physicians. Clinical studies may be financed by healthcare institutes, drug companies, academic medical centres, volunteer groups, physicians, healthcare service providers and other individuals. They may be conducted in several places including hospitals, universities, physicians’ offices and community clinics based on the researcher’s requirements. The participants are made aware of the duration of the study before their inclusion. Clinical studies should include the evaluation of recommendations (drug, device and surgical) for the treatment of a disease, syndrome or a comparison of one or more applications; finding different ways for recognition of a disease or case and prevention of their recurrence ( 7 ).

Clinical Research

In this review, clinical research is explained in more detail since it is the most valuable study in scientific research.

Clinical research starts with forming a hypothesis. A hypothesis can be defined as a claim put forward about the value of a population parameter based on sampling. There are two types of hypotheses in statistics.

• H 0 hypothesis is called a control or null hypothesis. It is the hypothesis put forward in research, which implies that there is no difference between the groups under consideration. If this hypothesis is rejected at the end of the study, it indicates that a difference exists between the two treatments under consideration.
• H 1 hypothesis is called an alternative hypothesis. It is hypothesised against a null hypothesis, which implies that a difference exists between the groups under consideration. For example, consider the following hypothesis: drug A has an analgesic effect. Control or null hypothesis (H 0 ): there is no difference between drug A and placebo with regard to the analgesic effect. The alternative hypothesis (H 1 ) is applicable if a difference exists between drug A and placebo with regard to the analgesic effect.

The planning phase comes after the determination of a hypothesis. A clinical research plan is called a protocol . In a protocol, the reasons for research, number and qualities of participants, tests to be applied, study duration and what information to be gathered from the participants should be found and conformity criteria should be developed.

The selection of participant groups to be included in the study is important. Inclusion and exclusion criteria of the study for the participants should be determined. Inclusion criteria should be defined in the form of demographic characteristics (age, gender, etc.) of the participant group and the exclusion criteria as the diseases that may influence the study, age ranges, cases involving pregnancy and lactation, continuously used drugs and participants’ cooperation.

The next stage is methodology. Methodology can be grouped under subheadings, namely, the calculation of number of subjects, blinding (masking), randomisation, selection of operation to be applied, use of placebo and criteria for stopping and changing the treatment.

I. Calculation of the Number of Subjects

The entire source from which the data are obtained is called a universe or population . A small group selected from a certain universe based on certain rules and which is accepted to highly represent the universe from which it is selected is called a sample and the characteristics of the population from which the data are collected are called variables. If data is collected from the entire population, such an instance is called a parameter . Conducting a study on the sample rather than the entire population is easier and less costly. Many factors influence the determination of the sample size. Firstly, the type of variable should be determined. Variables are classified as categorical (qualitative, non-numerical) or numerical (quantitative). Individuals in categorical variables are classified according to their characteristics. Categorical variables are indicated as nominal and ordinal (ordered). In nominal variables, the application of a category depends on the researcher’s preference. For instance, a female participant can be considered first and then the male participant, or vice versa. An ordinal (ordered) variable is ordered from small to large or vice versa (e.g. ordering obese patients based on their weights-from the lightest to the heaviest or vice versa). A categorical variable may have more than one characteristic: such variables are called binary or dichotomous (e.g. a participant may be both female and obese).

If the variable has numerical (quantitative) characteristics and these characteristics cannot be categorised, then it is called a numerical variable. Numerical variables are either discrete or continuous. For example, the number of operations with spinal anaesthesia represents a discrete variable. The haemoglobin value or height represents a continuous variable.

Statistical analyses that need to be employed depend on the type of variable. The determination of variables is necessary for selecting the statistical method as well as software in SPSS. While categorical variables are presented as numbers and percentages, numerical variables are represented using measures such as mean and standard deviation. It may be necessary to use mean in categorising some cases such as the following: even though the variable is categorical (qualitative, non-numerical) when Visual Analogue Scale (VAS) is used (since a numerical value is obtained), it is classified as a numerical variable: such variables are averaged.

Clinical research is carried out on the sample and generalised to the population. Accordingly, the number of samples should be correctly determined. Different sample size formulas are used on the basis of the statistical method to be used. When the sample size increases, error probability decreases. The sample size is calculated based on the primary hypothesis. The determination of a sample size before beginning the research specifies the power of the study. Power analysis enables the acquisition of realistic results in the research, and it is used for comparing two or more clinical research methods.

Because of the difference in the formulas used in calculating power analysis and number of samples for clinical research, it facilitates the use of computer programs for making calculations.

It is necessary to know certain parameters in order to calculate the number of samples by power analysis.

• Type-I (α) and type-II (β) error levels
• Difference between groups (d-difference) and effect size (ES)
• Distribution ratio of groups
• Direction of research hypothesis (H1)

a. Type-I (α) and Type-II (β) Error (β) Levels

Two types of errors can be made while accepting or rejecting H 0 hypothesis in a hypothesis test. Type-I error (α) level is the probability of finding a difference at the end of the research when there is no difference between the two applications. In other words, it is the rejection of the hypothesis when H 0 is actually correct and it is known as α error or p value. For instance, when the size is determined, type-I error level is accepted as 0.05 or 0.01.

Another error that can be made during a hypothesis test is a type-II error. It is the acceptance of a wrongly hypothesised H 0 hypothesis. In fact, it is the probability of failing to find a difference when there is a difference between the two applications. The power of a test is the ability of that test to find a difference that actually exists. Therefore, it is related to the type-II error level.

Since the type-II error risk is expressed as β, the power of the test is defined as 1–β. When a type-II error is 0.20, the power of the test is 0.80. Type-I (α) and type-II (β) errors can be intentional. The reason to intentionally make such an error is the necessity to look at the events from the opposite perspective.

b. Difference between Groups and ES

ES is defined as the state in which statistical difference also has clinically significance: ES≥0.5 is desirable. The difference between groups is the absolute difference between the groups compared in clinical research.

c. Allocation Ratio of Groups

The allocation ratio of groups is effective in determining the number of samples. If the number of samples is desired to be determined at the lowest level, the rate should be kept as 1/1.

d. Direction of Hypothesis (H1)

The direction of hypothesis in clinical research may be one-sided or two-sided. While one-sided hypotheses hypothesis test differences in the direction of size, two-sided hypotheses hypothesis test differences without direction. The power of the test in two-sided hypotheses is lower than one-sided hypotheses.

After these four variables are determined, they are entered in the appropriate computer program and the number of samples is calculated. Statistical packaged software programs such as Statistica, NCSS and G-Power may be used for power analysis and calculating the number of samples. When the samples size is calculated, if there is a decrease in α, difference between groups, ES and number of samples, then the standard deviation increases and power decreases. The power in two-sided hypothesis is lower. It is ethically appropriate to consider the determination of sample size, particularly in animal experiments, at the beginning of the study. The phase of the study is also important in the determination of number of subjects to be included in drug studies. Usually, phase-I studies are used to determine the safety profile of a drug or product, and they are generally conducted on a few healthy volunteers. If no unacceptable toxicity is detected during phase-I studies, phase-II studies may be carried out. Phase-II studies are proof-of-concept studies conducted on a larger number (100–500) of volunteer patients. When the effectiveness of the drug or product is evident in phase-II studies, phase-III studies can be initiated. These are randomised, double-blinded, placebo or standard treatment-controlled studies. Volunteer patients are periodically followed-up with respect to the effectiveness and side effects of the drug. It can generally last 1–4 years and is valuable during licensing and releasing the drug to the general market. Then, phase-IV studies begin in which long-term safety is investigated (indication, dose, mode of application, safety, effectiveness, etc.) on thousands of volunteer patients.

II. Blinding (Masking) and Randomisation Methods

When the methodology of clinical research is prepared, precautions should be taken to prevent taking sides. For this reason, techniques such as randomisation and blinding (masking) are used. Comparative studies are the most ideal ones in clinical research.

Blinding Method

A case in which the treatments applied to participants of clinical research should be kept unknown is called the blinding method . If the participant does not know what it receives, it is called a single-blind study; if even the researcher does not know, it is called a double-blind study. When there is a probability of knowing which drug is given in the order of application, when uninformed staff administers the drug, it is called in-house blinding. In case the study drug is known in its pharmaceutical form, a double-dummy blinding test is conducted. Intravenous drug is given to one group and a placebo tablet is given to the comparison group; then, the placebo tablet is given to the group that received the intravenous drug and intravenous drug in addition to placebo tablet is given to the comparison group. In this manner, each group receives both the intravenous and tablet forms of the drug. In case a third party interested in the study is involved and it also does not know about the drug (along with the statistician), it is called third-party blinding.

Randomisation Method

The selection of patients for the study groups should be random. Randomisation methods are used for such selection, which prevent conscious or unconscious manipulations in the selection of patients ( 8 ).

No factor pertaining to the patient should provide preference of one treatment to the other during randomisation. This characteristic is the most important difference separating randomised clinical studies from prospective and synchronous studies with experimental groups. Randomisation strengthens the study design and enables the determination of reliable scientific knowledge ( 2 ).

The easiest method is simple randomisation, e.g. determination of the type of anaesthesia to be administered to a patient by tossing a coin. In this method, when the number of samples is kept high, a balanced distribution is created. When the number of samples is low, there will be an imbalance between the groups. In this case, stratification and blocking have to be added to randomisation. Stratification is the classification of patients one or more times according to prognostic features determined by the researcher and blocking is the selection of a certain number of patients for each stratification process. The number of stratification processes should be determined at the beginning of the study.

As the number of stratification processes increases, performing the study and balancing the groups become difficult. For this reason, stratification characteristics and limitations should be effectively determined at the beginning of the study. It is not mandatory for the stratifications to have equal intervals. Despite all the precautions, an imbalance might occur between the groups before beginning the research. In such circumstances, post-stratification or restandardisation may be conducted according to the prognostic factors.

The main characteristic of applying blinding (masking) and randomisation is the prevention of bias. Therefore, it is worthwhile to comprehensively examine bias at this stage.

Bias and Chicanery

While conducting clinical research, errors can be introduced voluntarily or involuntarily at a number of stages, such as design, population selection, calculating the number of samples, non-compliance with study protocol, data entry and selection of statistical method. Bias is taking sides of individuals in line with their own decisions, views and ideological preferences ( 9 ). In order for an error to lead to bias, it has to be a systematic error. Systematic errors in controlled studies generally cause the results of one group to move in a different direction as compared to the other. It has to be understood that scientific research is generally prone to errors. However, random errors (or, in other words, ‘the luck factor’-in which bias is unintended-do not lead to bias ( 10 ).

Another issue, which is different from bias, is chicanery. It is defined as voluntarily changing the interventions, results and data of patients in an unethical manner or copying data from other studies. Comparatively, bias may not be done consciously.

In case unexpected results or outliers are found while the study is analysed, if possible, such data should be re-included into the study since the complete exclusion of data from a study endangers its reliability. In such a case, evaluation needs to be made with and without outliers. It is insignificant if no difference is found. However, if there is a difference, the results with outliers are re-evaluated. If there is no error, then the outlier is included in the study (as the outlier may be a result). It should be noted that re-evaluation of data in anaesthesiology is not possible.

Statistical evaluation methods should be determined at the design stage so as not to encounter unexpected results in clinical research. The data should be evaluated before the end of the study and without entering into details in research that are time-consuming and involve several samples. This is called an interim analysis . The date of interim analysis should be determined at the beginning of the study. The purpose of making interim analysis is to prevent unnecessary cost and effort since it may be necessary to conclude the research after the interim analysis, e.g. studies in which there is no possibility to validate the hypothesis at the end or the occurrence of different side effects of the drug to be used. The accuracy of the hypothesis and number of samples are compared. Statistical significance levels in interim analysis are very important. If the data level is significant, the hypothesis is validated even if the result turns out to be insignificant after the date of the analysis.

Another important point to be considered is the necessity to conclude the participants’ treatment within the period specified in the study protocol. When the result of the study is achieved earlier and unexpected situations develop, the treatment is concluded earlier. Moreover, the participant may quit the study at its own behest, may die or unpredictable situations (e.g. pregnancy) may develop. The participant can also quit the study whenever it wants, even if the study has not ended ( 7 ).

In case the results of a study are contrary to already known or expected results, the expected quality level of the study suggesting the contradiction may be higher than the studies supporting what is known in that subject. This type of bias is called confirmation bias. The presence of well-known mechanisms and logical inference from them may create problems in the evaluation of data. This is called plausibility bias.

Another type of bias is expectation bias. If a result different from the known results has been achieved and it is against the editor’s will, it can be challenged. Bias may be introduced during the publication of studies, such as publishing only positive results, selection of study results in a way to support a view or prevention of their publication. Some editors may only publish research that extols only the positive results or results that they desire.

Bias may be introduced for advertisement or economic reasons. Economic pressure may be applied on the editor, particularly in the cases of studies involving drugs and new medical devices. This is called commercial bias.

In recent years, before beginning a study, it has been recommended to record it on the Web site www.clinicaltrials.gov for the purpose of facilitating systematic interpretation and analysis in scientific research, informing other researchers, preventing bias, provision of writing in a standard format, enhancing contribution of research results to the general literature and enabling early intervention of an institution for support. This Web site is a service of the US National Institutes of Health.

The last stage in the methodology of clinical studies is the selection of intervention to be conducted. Placebo use assumes an important place in interventions. In Latin, placebo means ‘I will be fine’. In medical literature, it refers to substances that are not curative, do not have active ingredients and have various pharmaceutical forms. Although placebos do not have active drug characteristic, they have shown effective analgesic characteristics, particularly in algology applications; further, its use prevents bias in comparative studies. If a placebo has a positive impact on a participant, it is called the placebo effect ; on the contrary, if it has a negative impact, it is called the nocebo effect . Another type of therapy that can be used in clinical research is sham application. Although a researcher does not cure the patient, the researcher may compare those who receive therapy and undergo sham. It has been seen that sham therapies also exhibit a placebo effect. In particular, sham therapies are used in acupuncture applications ( 11 ). While placebo is a substance, sham is a type of clinical application.

Ethically, the patient has to receive appropriate therapy. For this reason, if its use prevents effective treatment, it causes great problem with regard to patient health and legalities.

Before medical research is conducted with human subjects, predictable risks, drawbacks and benefits must be evaluated for individuals or groups participating in the study. Precautions must be taken for reducing the risk to a minimum level. The risks during the study should be followed, evaluated and recorded by the researcher ( 1 ).

After the methodology for a clinical study is determined, dealing with the ‘Ethics Committee’ forms the next stage. The purpose of the ethics committee is to protect the rights, safety and well-being of volunteers taking part in the clinical research, considering the scientific method and concerns of society. The ethics committee examines the studies presented in time, comprehensively and independently, with regard to ethics and science; in line with the Declaration of Helsinki and following national and international standards concerning ‘Good Clinical Practice’. The method to be followed in the formation of the ethics committee should be developed without any kind of prejudice and to examine the applications with regard to ethics and science within the framework of the ethics committee, Regulation on Clinical Trials and Good Clinical Practice ( www.iku.com ). The necessary documents to be presented to the ethics committee are research protocol, volunteer consent form, budget contract, Declaration of Helsinki, curriculum vitae of researchers, similar or explanatory literature samples, supporting institution approval certificate and patient follow-up form.

Only one sister/brother, mother, father, son/daughter and wife/husband can take charge in the same ethics committee. A rector, vice rector, dean, deputy dean, provincial healthcare director and chief physician cannot be members of the ethics committee.

Members of the ethics committee can work as researchers or coordinators in clinical research. However, during research meetings in which members of the ethics committee are researchers or coordinators, they must leave the session and they cannot sign-off on decisions. If the number of members in the ethics committee for a particular research is so high that it is impossible to take a decision, the clinical research is presented to another ethics committee in the same province. If there is no ethics committee in the same province, an ethics committee in the closest settlement is found.

Thereafter, researchers need to inform the participants using an informed consent form. This form should explain the content of clinical study, potential benefits of the study, alternatives and risks (if any). It should be easy, comprehensible, conforming to spelling rules and written in plain language understandable by the participant.

This form assists the participants in taking a decision regarding participation in the study. It should aim to protect the participants. The participant should be included in the study only after it signs the informed consent form; the participant can quit the study whenever required, even when the study has not ended ( 7 ).

Peer-review: Externally peer-reviewed.

Author Contributions: Concept - C.Ö.Ç., A.D.; Design - C.Ö.Ç.; Supervision - A.D.; Resource - C.Ö.Ç., A.D.; Materials - C.Ö.Ç., A.D.; Analysis and/or Interpretation - C.Ö.Ç., A.D.; Literature Search - C.Ö.Ç.; Writing Manuscript - C.Ö.Ç.; Critical Review - A.D.; Other - C.Ö.Ç., A.D.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study has received no financial support.

Scientists push new paradigm of animal consciousness, saying even insects may be sentient

Bees play by rolling wooden balls — apparently for fun . The cleaner wrasse fish appears to recognize its own visage in an underwater mirror . Octopuses seem to react to anesthetic drugs and will avoid settings where they likely experienced past pain. 

All three of these discoveries came in the last five years — indications that the more scientists test animals, the more they find that many species may have inner lives and be sentient. A surprising range of creatures have shown evidence of conscious thought or experience, including insects, fish and some crustaceans. 

That has prompted a group of top researchers on animal cognition to publish a new pronouncement that they hope will transform how scientists and society view — and care — for animals. 

Nearly 40 researchers signed “ The New York Declaration on Animal Consciousness ,” which was first presented at a conference at New York University on Friday morning. It marks a pivotal moment, as a flood of research on animal cognition collides with debates over how various species ought to be treated. 

The declaration says there is “strong scientific support” that birds and mammals have conscious experience, and a “realistic possibility” of consciousness for all vertebrates — including reptiles, amphibians and fish. That possibility extends to many creatures without backbones, it adds, such as insects, decapod crustaceans (including crabs and lobsters) and cephalopod mollusks, like squid, octopus and cuttlefish.

“When there is a realistic possibility of conscious experience in an animal, it is irresponsible to ignore that possibility in decisions affecting that animal,” the declaration says. “We should consider welfare risks and use the evidence to inform our responses to these risks.” 

Jonathan Birch, a professor of philosophy at the London School of Economics and a principal investigator on the Foundations of Animal Sentience project, is among the declaration’s signatories. Whereas many scientists in the past assumed that questions about animal consciousness were unanswerable, he said, the declaration shows his field is moving in a new direction. 

“This has been a very exciting 10 years for the study of animal minds,” Birch said. “People are daring to go there in a way they didn’t before and to entertain the possibility that animals like bees and octopuses and cuttlefish might have some form of conscious experience.”

From 'automata' to sentient

There is not a standard definition for animal sentience or consciousness, but generally the terms denote an ability to have subjective experiences: to sense and map the outside world, to have capacity for feelings like joy or pain. In some cases, it can mean that animals possess a level of self-awareness. 

In that sense, the new declaration bucks years of historical science orthodoxy. In the 17th century, the French philosopher René Descartes argued that animals were merely “material automata” — lacking souls or consciousness.

Descartes believed that animals “can’t feel or can’t suffer,” said Rajesh Reddy, an assistant professor and director of the animal law program at Lewis & Clark College. “To feel compassion for them, or empathy for them, was somewhat silly or anthropomorphizing.” 

In the early 20th century, prominent behavioral psychologists promoted the idea that science should only study observable behavior in animals, rather than emotions or subjective experiences . But beginning in the 1960s, scientists started to reconsider. Research began to focus on animal cognition, primarily among other primates. 

Birch said the new declaration attempts to “crystallize a new emerging consensus that rejects the view of 100 years ago that we have no way of studying these questions scientifically.” 

Indeed, a surge of recent findings underpin the new declaration. Scientists are developing new cognition tests and trying pre-existing tests on a wider range of species, with some surprises. 

Take, for example, the mirror-mark test, which scientists sometimes use to see if an animal recognizes itself. 

In a series of studies, the cleaner wrasse fish seemed to pass the test . 

The fish were placed in a tank with a covered mirror, to which they exhibited no unusual reaction. But after the cover was lifted, seven of 10 fish launched attacks toward the mirror, signaling they likely interpreted the image as a rival fish. 

After several days, the fish settled down and tried odd behaviors in front of the mirror, like swimming upside down, which had not been observed in the species before. Later, some appeared to spend an unusual amount of time in front of the mirror, examining their bodies. Researchers then marked the fish with a brown splotch under the skin, intended to resemble a parasite. Some fish tried to rub the mark off. 

“The sequence of steps that you would only ever have imagined seeing with an incredibly intelligent animal like a chimpanzee or a dolphin, they see in the cleaner wrasse,” Birch said. “No one in a million years would have expected tiny fish to pass this test.”

In other studies, researchers found that zebrafish showed signs of curiosity when new objects were introduced into their tanks and that cuttlefish could remember things they saw or smelled . One experiment created stress for crayfish by electrically shocking them , then gave them anti-anxiety drugs used in humans. The drugs appeared to restore their usual behavior.

Birch said these experiments are part of an expansion of animal consciousness research over the past 10 to 15 years. “We can have this much broader canvas where we’re studying it in a very wide range of animals and not just mammals and birds, but also invertebrates like octopuses, cuttlefish,” he said. “And even increasingly, people are talking about this idea in relation to insects.”

As more and more species show these types of signs, Reddy said, researchers might soon need to reframe their line of inquiry altogether: “Scientists are being forced to reckon with this larger question — not which animals are sentient, but which animals aren’t?” 

New legal horizons

Scientists’ changing understanding of animal sentience could have implications for U.S. law, which does not classify animals as sentient on a federal level, according to Reddy. Instead, laws pertaining to animals focus primarily on conservation, agriculture or their treatment by zoos, research laboratories and pet retailers.

“The law is a very slow moving vehicle and it really follows societal views on a lot of these issues,” Reddy said. “This declaration, and other means of getting the public to appreciate that animals are not just biological automatons, can create a groundswell of support for raising protections.” 

State laws vary widely. A decade ago, Oregon passed a law recognizing animals as sentient and capable of feeling pain, stress and fear, which Reddy said has formed the bedrock of progressive judicial opinions in the state.  

Meanwhile, Washington and California are among several states where lawmakers this year have considered bans on octopus farming, a species for which scientists have found strong evidence of sentience. 

British law was recently amended to consider octopuses sentient beings — along with crabs and lobsters .

“Once you recognize animals as sentient, the concept of humane slaughter starts to matter, and you need to make sure that the sort of methods you’re using on them are humane,” Birch said. “In the case of crabs and lobsters, there are pretty inhumane methods, like dropping them into pans of boiling water, that are very commonly used.”

Evan Bush is a science reporter for NBC News. He can be reached at [email protected].

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China’s sinking cities indicate global-scale problem, Virginia Tech researcher says

A third of China’s urban population at risk of city sinking, new satellite data shows.

• Kelly Izlar

18 Apr 2024

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Sinking land is overlooked as a hazard in urban areas globally, according to scientists from Virginia Tech and the University of East Anglia in the United Kingdom. 

In an invited perspective article published April 18 for the journal  Science ,  Virginia Tech’s Manoochehr Shirzaei collaborated with Robert Nicholls of the University of East Anglia to highlight the importance of recent research analyzing how and why land is sinking — including a study published in the same issue that focused on sinking Chinese cities.  

Results from the accompanying research study showed that of the 82 Chinese cities analyzed, 45 percent are sinking. Nearly 270 million urban residents may be affected with hard-hit urban areas such as Beijing and Tianjin sinking at a rate of 10 millimeters a year or more. Land sinking, or subsidence, results in increased risk to roadways, runways, building foundations, rail lines, and pipelines.

The phenomenon isn’t limited to China, said Shirzaei.

“Land is sinking almost everywhere,” said Shirzaei, who was not involved in the China-focused study but whose  recent research  using satellite-monitoring techniques shed light on the growing dangers of sinking land along the U.S. East Coast. “If we don’t account for it in adaption and resilience plans now, we may be looking at widespread destruction of infrastructure in the next few decades.”

Shirzaei and Nicholls expounded on this concept in the perspective article, focusing on three major points.

Advances in satellite monitoring revealed the extent of land sinking for the first time

The technique used to map consistent large-scale measurements of sinking land in China relied on space-based radar. Over the past decade, advances in satellite imaging technology granted researchers like Shirzaei the ability to measure millimeter-scale changes in land level over days to years. 

“This is a relatively new technique,” said Shirzaei. “We didn’t have the data before. Now we have it, so we can use it — not only to see the problem, but to fix the problem.”

Land sinking is just an observation – more research is needed

While consistently measuring the sinking of urban land will provide a baseline to work from, predicting future subsidence requires models that consider all drivers, including human activities and climate change and how they might change with time.

Land sinking is mainly caused by human activity, but it can also be addressed with human activity

Land sinking is mainly caused by human action in the cities. Groundwater withdrawal, which lowers the water table, is considered the most important driver of subsidence, combined with geology and weight of buildings. Recharging the aquifer and reducing pumping can immediately mitigate land sinking.

Shirzaei and Nicholls called for the research community to move from measurement to understanding implications and supporting responses. 

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April 16, 2024

In Matters of Scientific Debate, Follow the Houdini Rule

Scientific expertise is typically limited and specific. When evaluating scientific claims, look to the relevant experts

By Naomi Oreskes

Scott Brundage

In the late 19th and early 20th centuries, leading scientists around the world believed that paranormal activity might be detected and demonstrated by scientific methods. The history of their attempts tells us something important about the limits and specificity of scientific expertise.

The Society for Psychical Research was founded in the U.K. in 1882 to in­­vestigate possible paranormal activity, ­including mesmerism, thought trans­ference, apparitions and even haunted houses. Prominent members included economist Henry Sidgwick, physicist Oliver Lodge (a pioneer in the study of electromagnetism), and writer Arthur Conan Doyle. These men sought to study the subject in a scientific manner , “without prejudice or pre­possession of any kind.” Other well-known scientists who attended séances included Harvard University psychologist and philosopher William James (one of the founders of a philosophical school known as pragmatism) and British biologist Alfred Russel Wallace (who, along with Charles Darwin, developed the theory of evolution by natural selection).

Mainstream media reported on these efforts, often uncritically. “Soul Has Weight, Physician Thinks,” declared a New York Times headline on March 11, 1907. With four medical colleagues as witnesses, “reputable physician” Duncan Mac­­Dougall of Massachusetts had placed the body of a dying man on a specially designed bed, with built-in scales, next to an empty but otherwise identical bed. At the moment of the man’s death, the scales reportedly shifted, indicating a weight loss on his side of approximately one ounce. Five other cases showed losses between an ounce and half an ounce. In the case of one large, “phlegmatic” man, the weight loss was delayed a minute; MacDougall concluded that the deceased’s sluggish nature led his soul to depart without alacrity. (Wikipedia suggests this experiment is the source of the popular notion that the human soul weighs 21 grams.)

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The Times similarly reported the work of Charles Henry, a mathematics professor at the Sorbonne in France. “Soul Can Be Measured, Mathematician Holds,” a headline announced on September 20, 1925. The evidence here consisted of radiating “biological vibration,” which ­occurred when death disrupted life’s delicate equilibrium. This observation marked “the first time science has ever admitted that tangible proof of the soul’s existence may be found,” the article asserted, insisting that the professor was not a “psychic or a dreamer” but a scientist who had harnessed “all the information available about colored auras and recollections of previous existences that so far have been almost exclusively exploited by cranks.”

These accounts remind us that the views of a scientist are not necessarily equivalent to “science.” MacDougall and Henry might have believed they had proved the soul’s existence, but most of their contemporaries did not. One obvious problem was that these experiments assumed the existence of the thing they were trying to prove—essentially a circular argument.

The history of psychical research also shows why we should take novel scientific claims with a grain of salt, especially those that would fulfill one of our dearest wishes, such as communicating with lost loved ones or enjoying eternal life. What seems plausible today—even at Harvard and the Sorbonne—may appear preposterous down the road.

Perhaps the most important lesson, though—especially in our current environment saturated with misinformation and disinformation —concerns the specificity of scientific expertise: scientists are specialists, and their training rarely prepares them to evaluate claims beyond their particular areas of focus.

What expertise, exactly, would be needed to evaluate claims of the supernatural or paranormal? Another tale from the annals of psychic inquiry helps to answer that question. It is the story of Boston medium Mina Crandon, popularly known as “Margery.”

In 1922 Scientific American announced the establishment of a prize committee to investigate psychic claims, promising $5,000 to anyone who could demonstrate the reality of paranormal or supernatural activity . Margery had been put forward as a candidate. Her evaluation committee included Harvard psychologist and member of the Royal Society William McDougall; Massachusetts Institute of Technology physicist Daniel F. Comstock (who later helped to develop the Technicolor process for making color movies); and world-renowned magician and escape artist Harry Houdini. Although the historical facts are somewhat disputed, it seems that the committee was leaning toward awarding Margery the prize until Houdini identified her techniques as the tricks they were. It was a magician—not a physicist or a mathematician—who had the expertise to recognize the supposed medium’s sleight of hand.

Nowadays all kinds of people make scientific claims, often with little or no expertise in the matter at hand. Some are scientists driving outside their lane. American physicist and inventor William Shockley, who shared the 1956 Nobel Prize in Physics for creating the transistor, used his stature to promote racism and eugenics.

Physicist John F. Clauser , a 2022 Nobel Laureate who was honored for his con­tributions to quantum information science, is a self-declared climate change “ denier ” who has been taking to podiums around the world to argue against the scientific consensus that the planet is undergoing dangerous warming. Various celebrities have falsely claimed that vaccines cause autism, and politician Robert F. Kennedy, Jr., is spreading misinformation about vaccines as part of a presidential campaign.

So the next time you are wondering whom to trust about a scientific matter, ask yourself this: Who has the necessary expertise to assess this situation? Put simply: Who is the Houdini in this case?

This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.

Research projects will partner students with DOE national labs to help students develop hands-on research experience

WASHINGTON, D.C . - Today, the U.S. Department of Energy (DOE)  announced $16 million in funding for four projects providing classroom training and research opportunities to train the next generation of accelerator scientists and engineers needed to deliver scientific discoveries. 

U.S. global competitiveness in discovery science relies on increasingly complex charged particle accelerator systems that require world-leading expertise to develop and operate. These programs will train the next generation of scientists and engineers, providing the expertise needed to lead activities supported by the DOE Office of Science. These programs will develop new curricula and guide a diverse cadre of graduate students working towards a master’s or Ph.D. thesis in accelerator science and engineering.

“Particle accelerator technology enables us to tackle challenges at the frontiers of science and benefits our nation’s high-tech industries, modern medicine, and national security,” said Regina Rameika, DOE Associate Director of Science for High Energy Physics. “The awards announced today will help to develop the workforce to advance the state-of-the-art in accelerator technology while helping deploy these technologies in commercial applications in the health, security, environmental, and industrial sectors. These programs at American universities will help ensure that our nation has a skilled and diverse workforce to develop the accelerator technology needed to meet the scientific challenges of the future.”

Research projects will partner students with DOE national labs to help students develop hands-on research experience. These projects include opportunities for graduate research across a broad range including beam physics at the systems level, technologies of large accelerators, high reliability design and failure analysis, and the fundamentals of project management. Students may also explore the material science, design methodology, fabrication techniques, and operations constraints needed to produce and operate superconducting radiofrequency accelerators. Additional research opportunities in the areas of high-reliability, high-power radiofrequency systems and large-scale cryogenic systems, particularly liquid helium systems, are available through these programs.

The projects were selected by competitive peer review under the DOE Funding Opportunity Announcement for DOE Traineeship in Accelerator Science & Engineering. 

Total funding is $16 million for projects lasting up to five years in duration, with $3 million in Fiscal Year 2024 dollars and outyear funding contingent on congressional appropriations. Funding is provided by the  High Energy Physics and the  Accelerator R&D and Production programs. The list of projects and more information can be found on the  High Energy Physics program homepage and the  Accelerator R&D and Production program homepage.

Selection for award negotiations is not a commitment by DOE to issue an award or provide funding. Before funding is issued, DOE and the applicants will undergo a negotiation process, and DOE may cancel negotiations and rescind the selection for any reason during that time. 

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These Scientists Rock. Literally.

The Pasteur Institute in Paris, known for its world-altering scientific research, has been making advancements in another field: the musical arts.

By Jessica Roy

Reporting from Paris

The Pasteur Institute, since opening in the 15th Arrondissement in Paris in the late 1880s, has been recognized for world-altering scientific discoveries. The institute, named for Louis Pasteur, the pioneering French scientist who founded it, has contributed to the production of vaccines for tetanus and the flu and was at the forefront of discovering the virus that causes AIDS .

In recent years, the Pasteur Institute has made advancements in another field — the musical arts — as some of its scientists have formed bands and other acts involving colleagues as well as students who have studied there. That cohort has honed its musical passion and ability at an on-site studio they call the music lab.

On a Friday evening in March, three acts developed in the lab headlined an event held at the institute’s cafeteria. They included Polaris and also Billie and the What?!, both blues-rock bands, and an a cappella group, Les Papillons, or “the butterflies” in English.

Moody purple light bathed the room, which was decorated with balloons and streamers in shades of pink, gold and white. It was filled with more than a hundred people, as well as with an array of equipment, including mics, speakers, guitars and an elaborate drum kit.

The drums belonged to Germano Cecere, a member of Billie and the What?! and a lab director at the Pasteur Institute whose research specializes in mechanisms of epigenetic inheritance. His job involves researching how organisms “don’t get only DNA from our parents, but also other stuff,” he said, using laymen’s terms.

Mr. Cecere, 44, was born in a small village near Naples, Italy. He started playing drums at age 9 and aspired to play professionally. In college and graduate school, he played in bands that toured across Italy. “I wanted to do music but my family said music is for fun — do something else,” he said.

That “something else” was earning a Ph.D. in human biology and genetics at the University of Rome, after which came some postdoctoral work at Columbia University in New York. He joined the Pasteur Institute staff in 2015.

Mr. Cecere has copper-colored hair that he wears pulled back into a low ponytail. He can talk animatedly for hours about topics that excite him, which include epigenetics, jazz and Neapolitan food. He is the kind of person who is good at a lot of things: In 2006, while he was completing his Ph.D., he made a short film called “ Borderline ” that premiered at a film festival in Rome and received a best cinematography award.

Mr. Cecere said that the Pasteur Institute has attracted many people who could play a guitar riff and explain the complexities of biochemistry with similar ease. Among them: Pedro Hernandez-Cerda, a developmental biologist and bass player who helped convince the institute’s leadership to create the music lab. (Mr. Hernandez-Cerda, who has since left the Pasteur Institute, lobbied for the lab with Camille Baussay, a singer and former human resources lawyer at the institute.)

The lab started as a place where employees who dabbled in music could meet up to jam. But it wasn’t long before those employees were forming musical groups and performing at department retreats and other work events.

Georg Braune, a member of Les Papillons a cappella group, described the lab as a sort of refuge. “You really have a lot of equipment,” said Mr. Braune, a 22-year-old master’s student researching brain development at the Pasteur Institute. “In the middle of the day we can go there, we can play. We can do whatever we want.”

Mr. Cecere said the lab has helped foster a stronger sense of community between the institute’s directors like himself and students or scientists in temporary programs. His band includes two other directors: Gérard Eberl, whose research is in microenvironments and immunity, plays guitar; Javier Pizarro-Cerda, whose research is in systems biology of bacterial infections, plays bass. Two doctoral students, Ana Choi and Alice Billie Libri, perform as vocalists.

Ms. Libri, 27, who is completing a Ph.D. in DNA repair, immunodeficiency and cancer, said the Pasteur Institute facilitated other activities like theater and drawing. “But I think music is the main activity,” she said. “There’s a choir, there are guitar lessons and stuff. It’s really nice.”

About halfway through the March event at the cafeteria, which was held to mark the 21st anniversary of a social committee at the institute, someone started handing out glow sticks. The crowd was grooving to covers performed by Billie and the What?! of songs like “Bad Guy” by Billie Eilish and “Smooth” by Santana as members of Les Papillons, who were costumed in butterfly wings, led a dance circle.

Pizzas and a towering cake made of doughnuts were served, along with beer and, of course, Champagne.

Before Billie and the What?! performed, Ms. Libri, who goes by Billie and whose name inspired that of the band, said that music is a way for her to escape when she’s “disappointed with science.”

And then, she added, “I can always go back to science when I’m disappointed with music.”

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Americans are divided on whether society overlooks racial discrimination or sees it where it doesn’t exist

Ahead of the 60th anniversary of the March on Washington for Black Americans’ civil rights, we asked U.S. adults what they think is the bigger problem when it comes to racial discrimination in the country today.

Pew Research Center conducted this analysis to explore how Americans view racial discrimination in the United States today compared with previous years. This question is a part of a broader study that asked Americans about their views on the Black Lives Matter movement and Martin Luther King Jr.’s legacy .

This analysis is based on a survey of 5,073 U.S. adults conducted April 10-16, 2023. Everyone who took part is a member of the Center’s American Trends Panel (ATP), an online survey panel that is recruited through national, random sampling of residential addresses. Address-based sampling ensures that nearly all U.S. adults have a chance of selection. The survey is weighted to be representative of the U.S. adult population by gender, race, ethnicity, partisan affiliation, education and other categories. Read more about the ATP’s methodology .

Here are the questions used for this analysis , along with responses, and the survey methodology .

• 53% say people not seeing racial discrimination where it really does exist is the bigger problem.
• 45% point to people seeing racial discrimination where it really doesn’t exist as the larger issue.

Views on this have changed in recent years, according to Pew Research Center surveys. In 2019, 57% said people overlooking racial discrimination was the bigger problem, while 42% pointed to people seeing it where it really didn’t exist. That gap has narrowed from 15 to 8 percentage points.

Americans’ current views on this question differ greatly by:

• Race and ethnicity: 88% of Black adults say people overlooking discrimination is the bigger problem. Smaller majorities of Asian (66%) and Hispanic (58%) adults say the same, as do 45% of White adults.

• Partisanship: 80% of Democrats and Democratic-leaning independents say people not seeing racial discrimination where it does exist is the larger issue. About three-quarters (74%) of Republicans and Republican leaners give the opposite answer.

How views on racial discrimination differ within political parties

Majorities of Republicans across age groups say people seeing racial discrimination where it doesn’t exist is the larger issue. But Republicans ages 50 and older are more likely than those under 50 to say this (78% vs. 68%).

Among Democrats, age differences aren’t as large, but there are differences by race and ethnicity. Hispanic Democrats are the most likely to say people seeing discrimination where it doesn’t exist is the bigger problem. Some 29% say this, compared with 20% of Asian Democrats, 19% of White Democrats and 8% of Black Democrats.

Note: Here are the questions used for this analysis , along with responses, and the survey methodology .

• Black Americans
• Discrimination & Prejudice
• Partisanship & Issues
• Racial Bias & Discrimination

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