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1.
Proc Natl Acad Sci U S A ; 121(22): e2313496121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38771874

RESUMO

Closing the achievement gap for minority students in higher education requires addressing the lack of belonging these students experience. This paper introduces a psychological intervention that strategically targets key elements within the learning environment to foster the success of minority students. The intervention sought to enhance Palestinian minority student's sense of belonging by increasing the presence of their native language. We tested the effectiveness of the intervention in two field experiments in Israel (n > 20,000), at the height of the COVID-19 pandemic when all classes were held via Zoom. Lecturers in the experimental condition added a transcript of their names in Arabic to their default display (English/Hebrew only). Our findings revealed a substantial and positive impact on Palestinian student's sense of belonging, class participation, and overall grades. In experiment 1, Palestinian student's average grade increased by 10 points. In experiment 2, there was an average increase of 4 points among Palestinian students' semester grade. Our intervention demonstrates that small institutional changes when carefully crafted can have a significant impact on minority populations. These results have significant implications for addressing educational disparities and fostering inclusive learning environment.


Assuntos
Árabes , COVID-19 , Grupos Minoritários , Estudantes , Humanos , Israel , Grupos Minoritários/educação , Grupos Minoritários/psicologia , Estudantes/psicologia , COVID-19/epidemiologia , Feminino , Árabes/psicologia , Masculino , Aprendizagem , Educação a Distância/métodos , SARS-CoV-2
2.
Proc Natl Acad Sci U S A ; 120(16): e2218621120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37040414

RESUMO

Intergroup prejudice is pervasive in many contexts worldwide, leading to discrimination and conflict. Existing research suggests that prejudice is acquired at an early age and that durably improving intergroup relations is extremely challenging, often requiring intense interventions. Building on existing research in social psychology and inspired by the Israeli TV series "You Can't Ask That," which depicts charismatic children from minority groups broaching sensitive topics at the core of intergroup relations, we develop a month-long diversity education program. Our program exposed students to the TV series and facilitated follow-up classroom discussions in which students constructively addressed various sensitive topics at the core of intergroup relations and learned about intergroup similarities, intragroup heterogeneity, and the value of taking others' perspectives. Through two field experiments implemented in Israeli schools, we show that integrating our intervention into school curricula improved Jewish students' attitudes toward minorities and increased some pro-diversity behavior up to 13 wk posttreatment. We further provide suggestive evidence that the intervention was effective by encouraging students to take their outgroups' perspectives and address an element of scalability by delegating implementation responsibilities to classroom teachers in our second study. Our findings suggest that theoretically informed intensive education programs are a promising route to reducing prejudice at a young age.


Assuntos
Atitude , Preconceito , Criança , Humanos , Israel , Instituições Acadêmicas , Grupos Minoritários
3.
Health Econ ; 33(8): 1705-1725, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38511402

RESUMO

This paper analyses the impact of a healthy food nudge intervention on purchases of 1590 customers of a supermarket chain's loyalty program in Uruguay through a randomized controlled trial. Nudges were presented in the form of messages sent through WhatsApp to customers three times a week for 8 weeks (between July and September 2020). Messages highlighted the benefits of cooking at home and eating mindfully and healthy (vegetables, fruits, healthy snacks, legumes, and fish), and included easy to implement tips. Results show that, on average, customers assigned to the treatment group increased their purchases of healthy food by 8% and substituted sugar-sweetened for sugar-free beverages. We find an unintended increase in purchases of unhealthy food of 7%, with no correlative increase in calories, suggesting that customers substituted higher calorie products for lower calorie ones. We find that households with lower educational attainment, lower income, and with children under the age of 12 are more likely to increase purchases of fruits and vegetables, while other households are more likely to improve the diet quality without increasing expenditure. Effects do not persist after the intervention is over, suggesting that salience, rather than information is the main channel triggering the effects.


Assuntos
Comportamento de Escolha , Dieta Saudável , Supermercados , Humanos , Feminino , Masculino , Uruguai , Adulto , Preferências Alimentares , Pessoa de Meia-Idade , Comportamento do Consumidor , Promoção da Saúde/métodos , Fatores Socioeconômicos
4.
Br J Sociol ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39380210

RESUMO

Decades of field experiments show that White Americans are more likely to discriminate against Black Americans when the situation provides a nonracist rationalization for withholding help from a Black target - for instance, when the cost of helping looks unreasonable. However, work on racial discrimination in helping is scarcer outside of the US context. The present experiment extends this line of research to Europe and studies differences in helping asiatique (Asian), blanc (White) and noir (Black) men and women in France. In addition, it assesses to what extent racial discrimination in the probability to provide assistance is moderated by the perceived cost of help. The study rests on a sample of over 4500 independent observations collected through a factorial design that combines 12 testers (equally apportioned in race and gender groups), two social class conditions and four observation sites. Testers asked for directions to pedestrians in front of the traffic lights of a busy road, and pedestrians could provide different forms of help that varied in perceived cost. The analysis indicates that overall asiatique and noir testers receive help less often than their blanc counterparts. It also shows that racial discrimination is stronger when the perceived cost of helping is higher.

5.
Planta ; 258(3): 60, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37535207

RESUMO

MAIN CONCLUSION: Nicotiana attenuata's capacity to interact with arbuscular mycorrhizal fungi influences its intraspecific competitive ability under field and glasshouse conditions, but not its overall community productivity. Arbuscular mycorrhizal (AM) fungi can alter the nutrient status and growth of plants, and they can also affect plant-plant, plant-herbivore, and plant-pathogen interactions. These AM effects are rarely studied in populations under natural conditions due to the limitation of non-mycorrhizal controls. Here we used a genetic approach, establishing field and glasshouse communities of AM-harboring Nicotiana attenuata empty vector (EV) plants and isogenic plants silenced in calcium- and calmodulin-dependent protein kinase expression (irCCaMK), and unable to establish AM symbioses. Performance and growth were quantified in communities of the same (monocultures) or different genotypes (mixed cultures) and both field and glasshouse experiments returned similar responses. In mixed cultures, AM-harboring EV plants attained greater stalk lengths, shoot and root biomasses, clearly out-competing the AM fungal-deficient irCCaMK plants, while in monocultures, both genotypes grew similarly. Competitive ability was also reflected in reproductive traits: EV plants in mixed cultures outperformed irCCaMK plants. When grown in monocultures, the two genotypes did not differ in reproductive performance, though total leaf N and P contents were significantly lower independent of the community type. Plant productivity in terms of growth and seed production at the community level did not differ, while leaf nutrient content of phosphorus and nitrogen depended on the community type. We infer that AM symbioses drastically increase N. attenuata's competitive ability in mixed communities resulting in increased fitness for the individuals harboring AM without a net gain for the community.


Assuntos
Micorrizas , Micorrizas/fisiologia , Raízes de Plantas , Plantas , Nicotiana/genética , Nicotiana/microbiologia , Biomassa , Fungos/fisiologia , Solo , Simbiose
6.
J Exp Biol ; 226(Suppl_1)2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37073956

RESUMO

Studying the motion of cheetahs - especially in the wild - is a technically challenging endeavour that pushes the limits of field biomechanics methodology. Consequently, it provides an interesting example of the scientific symbiosis that exists between experimental biology and the technological disciplines that support it. This article uses cheetah motion research as a basis to review the past, present and likely future of field biomechanics. Although the focus is on a specific animal, the methods and challenges discussed are broadly relevant to the study of terrestrial locomotion. We also highlight the external factors contributing to the evolution of this technology, including recent advancements in machine learning, and the influx of interest in cheetah biomechanics from the legged robotics community.


Assuntos
Acinonyx , Robótica , Animais , Fenômenos Biomecânicos , Locomoção , Movimento (Física)
7.
J Anim Ecol ; 92(8): 1478-1488, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36180982

RESUMO

Determining the cultural propensities or cultural behaviours of a species during foraging entails an investigation of underlying drivers and motivations. In this article, we propose a multicomponent approach involving behaviour, ecology, and physiology to accelerate the study of cultural propensities in the wild. We propose as the first component the use of field experiments that simulate natural contexts, such as foraging behaviours and tool use opportunities, to explore social learning and cultural tendencies in a variety of species. To further accelerate this component, we discuss and advocate for the use of modern machine learning video analysis tools. In conjunction, we examine non-invasive methods to measure ecological influences on foraging such as phenology, fruit availability, dietary intake; and physiological influences such as stress, protein balance, energetics, and metabolism. We feature non-invasive urine sampling to investigate urea, creatinine, ketone bodies, the thyroid hormone triiodothyronine (T3), cortisol and connecting peptides of insulin. To conclude, we highlight the benefits of combining ecological and physiological conditions with behavioural field experiments. This can be done across wild species, and provides the framework needed to test ecological hypotheses related to cultural behaviour.


Assuntos
Animais
8.
J Anim Ecol ; 92(8): 1489-1508, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36914973

RESUMO

Disgust is an adaptive system hypothesized to have evolved to reduce the risk of becoming sick. It is associated with behavioural, cognitive and physiological responses tuned to allow animals to avoid and/or get rid of parasites, pathogens and toxins. Little is known about the mechanisms and outcomes of disease avoidance in wild animals. Furthermore, given the escalation of negative human-wildlife interactions, the translation of such knowledge into the design of evolutionarily relevant conservation and wildlife management strategies is becoming urgent. Contemporary methods in animal ecology and related fields, using direct (sensory cues) or indirect (remote sensing technologies and machine learning) means, provide a flexible toolbox for testing and applying disgust at individual and collective levels. In this review/perspective paper, we provide an empirical framework for testing the adaptive function of disgust and its associated disease avoidance behaviours across species, from the least to the most social, in different habitats. We predict various trade-offs to be at play depending on the social system and ecology of the species. We propose five contexts in which disgust-related avoidance behaviours could be applied, including endangered species rehabilitation, invasive species, crop-raiding, urban pests and animal tourism. We highlight some of the perspectives and current challenges of testing disgust in the wild. In particular, we recommend future studies to consider together disease, predation and competition risks. We discuss the ethics associated with disgust experiments in the above contexts. Finally, we promote the creation of a database gathering disease avoidance evidence in animals and its applications.


Le dégoût est un système adaptatif supposé avoir évolué afin de réduire le risque de tomber malade. Il est associé à des réponses comportementales, cognitives et physiologiques adaptées pour permettre aux animaux d'éviter et/ou de se débarrasser des parasites, pathogènes et toxines. On sait peu de choses sur les mécanismes et les conséquences de l'évitement des maladies chez les animaux sauvages. Étant donné l'escalade des interactions négatives entre humains et faune, la traduction de ces connaissances dans la conception de stratégies de conservation et de gestion de la faune - prenant en considération l'évolution des espèces - devient urgente. Les méthodes contemporaines en écologie animale et dans les domaines connexes, utilisant des moyens directs (indices sensoriels) ou indirects (technologies de télédétection et apprentissage automatique), fournissent une boîte à outils flexible pour tester et appliquer le dégoût aux niveaux individuel et collectif. Dans cet article de revue/perspective, nous fournissons un cadre empirique pour tester la fonction adaptative du dégoût et les comportements associés d'évitement des maladies chez différentes espèces - des moins sociales aux plus sociales, et dans différents habitats. Nous prédisons divers compromis en fonction du système social et de l'écologie de l'espèce. Nous proposons cinq contextes dans lesquels les comportements d'évitement liés au dégoût pourraient être appliqués: la réhabilitation d'espèces menacées; les espèces envahissantes; les dommages aux cultures; les nuisibles urbains; et le tourisme animalier. Nous mettons en avant certaines perspectives et défis actuels de l'expérimentation sur le dégoût en milieu naturel. En particulier, nous recommandons la considération de plusieurs risques ensemble: maladie, prédation et compétition. Nous discutons également de l'éthique associée aux expériences sur le dégoût dans les contextes ci-dessus. Enfin, nous promouvons la création d'une base de données rassemblant les stratégies d'évitement des maladies chez les animaux et leurs applications.


Assuntos
Asco , Parasitos , Animais , Humanos , Animais Selvagens , Sinais (Psicologia) , Aprendizagem da Esquiva
9.
Oecologia ; 203(3-4): 277-296, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37773450

RESUMO

After an overview of the discussion about the existence of intra- and interspecific competition that illustrates the contradictory opinions I conclude that long-term field experiments are needed for firm conclusions. I discuss in some detail the role of two factors that limit population size of secondary cavity nesting birds e.g. territorial behavior and adequate cavities. This is followed by an overview of experimental long-term field studies in Belgium showing that intra- and interspecific competition in a great tit-blue tit system exists. By using nestbox configurations with high densities of nestboxes that differ in the diameter of their entrance hole in replicate study plots it is possible to manipulate the breeding densities of great tit Parus major and blue tit Cyanistes caeruleus independently, thereby varying the intensity of intra- and interspecific competition between these two coexisting species. When blue tit densities are experimentally increased local recruitment of great tits increases, and adult great tit post-breeding dispersal to other study plots decreases, implying that great tits use blue tit density to evaluate habitat quality and that high blue tit density results in heterospecific attraction. The reverse is not true. An experimental increase in great tit density leading to an increase in interspecific competition in a plot where blue tit density was already high leads to a decrease in blue tit nestling mass (illustrating interspecific competition for food), but to a gradual increase in blue tit body size. Both are primarily caused by an increase in the body size of immigrants (caused by intraspecific competition for protected roosting holes) in contrast to the control plot, where neither is observed. I also summarize behavioral, ecological and possible evolutionary effects of sparrowhawks on blue tits after sparrowhawks settled in an isolated study plot halfway through the study: adult survival substantially decreased for both sexes, but more for females that laid large clutches, leading to selection for females that laid a smaller clutch. This led to a change in the reproduction/survival life-history trade-off. Adult winter weights and nestling weights decreased, and the heaviest fledglings were selected against. Furthermore the frequency of polygyny increased. The long-term experiments also document the role of the use of public information and that species that compete can be attracted to sites in which competitor density is high.


Assuntos
Passeriformes , Aves Canoras , Feminino , Animais , Masculino , Comportamento Predatório , Ecossistema , Densidade Demográfica
10.
Proc Natl Acad Sci U S A ; 117(48): 30014-30021, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33229586

RESUMO

In 1966, Henry Beecher published his foundational paper "Ethics and Clinical Research," bringing to light unethical experiments that were routinely being conducted by leading universities and government agencies. A common theme was the lack of voluntary consent. Research regulations surrounding laboratory experiments flourished after his work. More than half a century later, we seek to follow in his footsteps and identify a new domain of risk to the public: certain types of field experiments. The nature of experimental research has changed greatly since the Belmont Report. Due in part to technological advances including social media, experimenters now target and affect whole societies, releasing interventions into a living public, often without sufficient review or controls. A large number of social science field experiments do not reflect compliance with current ethical and legal requirements that govern research with human participants. Real-world interventions are being conducted without consent or notice to the public they affect. Follow-ups and debriefing are routinely not being undertaken with the populations that experimenters injure. Importantly, even when ethical research guidelines are followed, researchers are following principles developed for experiments in controlled settings, with little assessment or protection for the wider societies within which individuals are embedded. We strive to improve the ethics of future work by advocating the creation of new norms, illustrating classes of field experiments where scholars do not appear to have recognized the ways such research circumvents ethical standards by putting people, including those outside the manipulated group, into harm's way.


Assuntos
Ética em Pesquisa , Experimentação Humana/ética , Experimentação Humana/normas , Humanos , Padrões de Referência , Risco , Mídias Sociais , Ciências Sociais
11.
Proc Natl Acad Sci U S A ; 117(32): 18948-18950, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32719133

RESUMO

We resolve a controversy over two competing hypotheses about why people object to randomized experiments: 1) People unsurprisingly object to experiments only when they object to a policy or treatment the experiment contains, or 2) people can paradoxically object to experiments even when they approve of implementing either condition for everyone. Using multiple measures of preference and test criteria in five preregistered within-subjects studies with 1,955 participants, we find that people often disapprove of experiments involving randomization despite approving of the policies or treatments to be tested.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Pesquisa/normas , Ética em Pesquisa , Humanos , Distribuição Aleatória , Ensaios Clínicos Controlados Aleatórios como Assunto/ética
12.
Sensors (Basel) ; 23(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37430783

RESUMO

The rail conveyor is a new type of energy-saving system for the long-distance transportation of bulk materials. Operating noise is an urgent problem that the current model faces. It will cause noise pollution and affect the health of workers. In this paper, the factors causing vibration and noise are analyzed by modeling the wheel-rail system and the supporting truss structure. Based on the built test platform, the system vibration of the vertical steering wheel, the track support truss, and the track connection were measured, and the vibration characteristics at different positions were analyzed. Based on the established noise and vibration model, the distribution and occurrence rules of system noise under different operating speeds and fastener stiffness conditions were obtained. The experimental results show that the vibration amplitude of the frame near the head of the conveyor is the largest. The amplitude under the condition of 2 m/s running speed at the same position is 4 times that under the condition of 1 m/s. At different welds of the track, the width and depth of the rail gap have a great influence on the vibration impact, which is mainly due to the impact of the uneven impedance at the track gap, and the greater the running speed, the more obvious the vibration impact. The simulation results show the trend of noise generation, the speed of the trolley, and the stiffness of the track fasteners have a positive effect on the generation of noise in the low-frequency region. The research results of this paper will play an important role in the noise and vibration analysis of rail conveyors and help to optimize the structure design of the track transmission system.

13.
Int J Mol Sci ; 24(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38139253

RESUMO

Ammonium, as a major inorganic source of nitrogen (N) for sweet potato N utilization and growth, is specifically transported by ammonium transporters (AMTs). However, the activities of AMT family members in sweet potatoes have not been analyzed. In the present study, the sweet potato cultivar 'Pushu 32', which is planted in a large area in China, was used in field experiments at the Agricultural Base of Hainan University (20°06' N, 110°33' E) in 2021, and Sanya Nanfan Research Institute of Hainan University (18°30' N, 109°60' E) in 2022. Four N levels were tested: 0, 60, 120, and 180 kg ha-1. The results are as follows. Twelve IbAMT genes were identified in the sweet potato genome, which were classified into three distinct subgroups based on phylogeny; the same subgroup genes had similar properties and structures. IbAMT1.3 and IbAMT1.5 were mostly expressed in the storage roots under N deficiency. Compared with the NN and HN groups, IbAMT1.3 and IbAMT1.5 expressions, N content in storage roots, N uptake efficiency at the canopy closure, N fertilization contribution rates, number of storage roots per plant, storage root weight, and yield were all increased in the MN group. Furthermore, there was a significant positive correlation between the expressions of IbAMT1.3 and IbAMT1.5 with N content in the storage roots of sweet potato. In a word, IbAMT1.3 and IbAMT1.5 may regulate N utilization, affect the development of the storage root. and determine the yield of sweet potato. The results provide valuable insights into the AMT gene family's role in the use of N and effects on storage root development and yield in sweet potatoes.


Assuntos
Ipomoea batatas , Humanos , Ipomoea batatas/metabolismo , Agricultura , Nitrogênio/metabolismo , China , Raízes de Plantas/metabolismo
14.
Planta ; 255(2): 39, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35032192

RESUMO

MAIN CONCLUSION: Higher acclimated freezing tolerance improved winter survival, but reduced reproductive fitness of Arabidopsis thaliana accessions under field and controlled conditions. Low temperature is one of the most important abiotic factors influencing plant fitness and geographical distribution. In addition, cold stress is known to influence crop yield and is therefore of great economic importance. Increased freezing tolerance can be acquired by the process of cold acclimation, but this may be associated with a fitness cost. To assess the influence of cold stress on the fitness of plants, long-term field trials over 5 years were performed with six natural accessions of Arabidopsis thaliana ranging from very tolerant to very sensitive to freezing. Fitness parameters, as seed yield and 1000 seed mass, were measured and correlation analyses with temperature and freezing tolerance data performed. The results were compared with fitness parameters from controlled chamber experiments over 3 years with application of cold priming and triggering conditions. Winter survival and seed yield per plant were positively correlated with temperature in field experiments. In addition, winter survival and 1000 seed mass were correlated with the cold-acclimated freezing tolerance of the selected Arabidopsis accessions. The results provide strong evidence for a trade-off between higher freezing tolerance and reproductive fitness in A. thaliana, which might have ecological impacts in the context of global warming.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Aclimatação , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Resposta ao Choque Frio , Congelamento , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo
15.
J Hum Evol ; 171: 103250, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36122461

RESUMO

When and how human ancestors first used tools remains unknown, despite intense research into the origins of technology. It has been hypothesized that the evolutionary roots of stone flake technology has its origin in percussive behavior. Before intentional stone flaking, hominins potentially engaged in various percussive behaviors resulting in accidental flake detachments. We refer to this scenario as the 'by-product hypothesis.' In this scenario, repeated detachments of sharp stone fragments eventually resulted in intentional flake production. Here, we tested the circumstances of accidental flake production as a by-product of percussive foraging in wild capuchin monkeys (Sapajus libidinosus) from Brazil, the only nonhuman primate known to habitually produce sharp-edged flakes through a percussive behavior. We conducted field experiments where we tested the potential for accidental flake production during nut cracking. We provided three different types of stone with varied material properties as anvils to assess the circumstances in which accidental production of sharp-edged flakes occurs during nut cracking. A further freehand knapping experiment, with the raw material that exhibited accidental flake detachments, allows a direct comparison of flakes that have been intentionally produced by an experienced knapper and flakes produced during nut cracking by capuchin monkeys. Our results show that raw material quality and morphology significantly affect the rate of sharp-edged flake production as well as the resulting lithic signature of this behavior. In addition, accidental flakes produced during capuchin nut cracking on highly isotropic raw material are similar in many respects to intentionally produced flakes by a human knapper. Our field experiments highlight the fact that nut-cracking behavior can lead to the unintentional production of substantial quantities of sharp-edged flakes and therefore supports the 'by-product hypothesis' as a potential mechanism for the emergence of hominin flake technology.


Assuntos
Hominidae , Comportamento de Utilização de Ferramentas , Animais , Arqueologia , Evolução Biológica , Cebus , Humanos , Tecnologia
16.
Oecologia ; 199(4): 995-1005, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35939137

RESUMO

Climate warming and increased atmospheric nitrogen deposition are both predicted to alter the primary productivity of grass-dominated systems in the coming decades. In field experiments, while both factors can have substantial effects on productivity in the initial years, further changes can be delayed by lags in plant species composition responses. However, the effects of experiment age can be confounded by annual variability in environmental conditions, and a replicate experiment established at a later time is therefore needed to separate these effects. We added new warming and nitrogen plots to an ongoing (14 year-old) field experiment in a grass-dominated temperate old field to compare the short-term vs. long-term treatment effects on plant productivity and species composition, while controlling for interannual environmental variability. We predicted treatment effects on relative species abundances would be most pronounced in the old plots. Although treatment responses of productivity (specifically to N addition) were highest in the old plots in the first year, by the second year there were no interactions between treatment and plot age. Moreover, there were no plot age effects on plant species composition, which was associated with continued dominance of non-native grasses. Our results therefore suggest that despite initial increases in productivity in response to global change, dominance by non-native grasses can suppress the emergence of further long-term treatment effects on productivity by inhibiting the responses of other species.


Assuntos
Ecossistema , Poaceae , Clima , Mudança Climática , Nitrogênio , Plantas , Poaceae/fisiologia
17.
Proc Natl Acad Sci U S A ; 116(21): 10329-10332, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31064877

RESUMO

Police body-worn cameras (BWCs) have been widely promoted as a technological mechanism to improve policing and the perceived legitimacy of police and legal institutions, yet evidence of their effectiveness is limited. To estimate the effects of BWCs, we conducted a randomized controlled trial involving 2,224 Metropolitan Police Department officers in Washington, DC. Here we show that BWCs have very small and statistically insignificant effects on police use of force and civilian complaints, as well as other policing activities and judicial outcomes. These results suggest we should recalibrate our expectations of BWCs' ability to induce large-scale behavioral changes in policing, particularly in contexts similar to Washington, DC.


Assuntos
Fotografação/estatística & dados numéricos , Polícia/estatística & dados numéricos , District of Columbia , Humanos , Comportamento Social
18.
Proc Natl Acad Sci U S A ; 116(22): 10723-10728, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31072934

RESUMO

Randomized experiments have enormous potential to improve human welfare in many domains, including healthcare, education, finance, and public policy. However, such "A/B tests" are often criticized on ethical grounds even as similar, untested interventions are implemented without objection. We find robust evidence across 16 studies of 5,873 participants from three diverse populations spanning nine domains-from healthcare to autonomous vehicle design to poverty reduction-that people frequently rate A/B tests designed to establish the comparative effectiveness of two policies or treatments as inappropriate even when universally implementing either A or B, untested, is seen as appropriate. This "A/B effect" is as strong among those with higher educational attainment and science literacy and among relevant professionals. It persists even when there is no reason to prefer A to B and even when recipients are treated unequally and randomly in all conditions (A, B, and A/B). Several remaining explanations for the effect-a belief that consent is required to impose a policy on half of a population but not on the entire population; an aversion to controlled but not to uncontrolled experiments; and a proxy form of the illusion of knowledge (according to which randomized evaluations are unnecessary because experts already do or should know "what works")-appear to contribute to the effect, but none dominates or fully accounts for it. We conclude that rigorously evaluating policies or treatments via pragmatic randomized trials may provoke greater objection than simply implementing those same policies or treatments untested.


Assuntos
Ética em Pesquisa , Ensaios Clínicos Pragmáticos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Ensaios Clínicos Pragmáticos como Assunto/ética , Ensaios Clínicos Pragmáticos como Assunto/legislação & jurisprudência , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/legislação & jurisprudência , Resultado do Tratamento
19.
Sensors (Basel) ; 22(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35062622

RESUMO

As the number of research activities and practical deployments of unmanned vehicles has shown a rapid growth, topics related to their communication with operator and external infrastructure became of high importance. As a result a trend of employing IP communication for this purpose is emerging and can be expected to bring significant advantages. However, its employment can be expected to be most effective using broadband communication technologies such as Wireless Local Area Networks (WLANs). To verify the effectiveness of such an approach in a specific case of surface unmanned vehicles, the paper includes an overview of IP-based MAVLink communication advantages and requirements, followed by a laboratory and field-experiment study of selected WLAN technologies, compared to popular narrowband communication solutions. The conclusions confirm the general applicability of IP/WLAN communication for surface unmanned vehicles, providing an overview of their advantages and pointing out deployment requirements.

20.
J Environ Manage ; 313: 114974, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35447410

RESUMO

Shanxi is a large coal-producing province, and it also produces a lot of solid waste. Solid waste can leach heavy metals, which can harm soil and affect food security at the beginning of the food chain. To investigate the impacts of solid waste-based soil conditioner (SWSC) and arbuscular mycorrhizal fungi (AMF) on millet safety and crop production, a field experiment with foxtail millet (Setaria italica) was conducted in Tunliu. The results of this study demonstrate that SWSC + AMF, SWSC and AMF can increase millet yield by 28.0%, 27.1% and 19.5%, respectively, compared with CK. This is mainly due to increased mycorrhizal infection. Besides, the pollution index (Pi) and the Nemerow-integrated pollution index (PN) of the soil with SWSC and AMF were both below 0.7, indicating safe pollution levels. The application of AMF and SWSC inhibits plants from absorbing heavy metals from the soil and reduces the TFroot/soil of the millet. SWSC + AMF application inhibited the transfer of heavy metals from the roots to the upper part of the ground and reduced the TFshoot/root of the millet. The TFgrain/soil of the millet was below 1. The HQ and HI of the millet grains did not exceed 1, indicating the absence of a potential health risk. Therefore, SWSC combined with AMF is applicable for millet production in Tunliu, and the combined treatment can decrease heavy metal phytoavailability and post-harvest transfer risks. This work provides a way to utilize solid waste while also improving millet yields in dry farming. Based on the review, we suggested future researches to better understand the mechanisms of SWSC + AMF long-term application to promote awareness on its role over time through alterations in its surface chemistry, soil microbial community and environmental implications.


Assuntos
Metais Pesados , Micorrizas , Setaria (Planta) , Poluentes do Solo , Produção Agrícola , Fungos , Metais Pesados/análise , Micorrizas/química , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , Resíduos Sólidos
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