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Ross H. Nehm Therese M. Poole Mark E. Lyford Sally G. Hoskins Laura Carruth Brent E. Ewers Patricia J. S. Colberg 《Evolution》2009,2(3):527-532
The well-established finding that substantial confusion and misconceptions about evolution and natural selection persist after
college instruction suggests that these courses neither foster accurate mental models of evolution’s mechanisms nor instill
an appreciation of evolution’s centrality to an understanding of the living world. Our essay explores the roles that introductory
biology courses and textbooks may play in reinforcing undergraduates’ pre-existing, faulty mental models of the place of evolution
in the biological sciences. Our content analyses of the three best-selling introductory biology textbooks for majors revealed
the conceptual segregation of evolutionary information. The vast majority of the evolutionary terms and concepts in each book
were isolated in sections about evolution and diversity, while remarkably few were employed in other sections of the books.
Standardizing the data by number of pages per unit did not alter this pattern. Students may fail to grasp that evolution is
the unifying theme of biology because introductory courses and textbooks reinforce such isolation. Two goals are central to
resolving this problem: the desegregation of evolution as separate “units” or chapters and the active integration of evolutionary
concepts at all levels and across all domains of introductory biology. 相似文献
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Andreasen V 《Bulletin of mathematical biology》2011,73(10):2305-2321
We study the final size equation for an epidemic in a subdivided population with general mixing patterns among subgroups.
The equation is determined by a matrix with the same spectrum as the next generation matrix and it exhibits a threshold controlled
by the common dominant eigenvalue, the basic reproduction number R0{\mathcal{R}_{0}}: There is a unique positive solution giving the size of the epidemic if and only if R0{\mathcal{R}_{0}} exceeds unity. When mixing heterogeneities arise only from variation in contact rates and proportionate mixing, the final
size of the epidemic in a heterogeneously mixing population is always smaller than that in a homogeneously mixing population
with the same basic reproduction number R0{\mathcal{R}_{0}}. For other mixing patterns, the relation may be reversed. 相似文献
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Gernot Schmid Rene Hirtl Ana Bueno-Lopez Hans Dorn Torsten Eggert Heidi Danker-Hopfe 《Bioelectromagnetics》2020,41(3):230-240
A new head exposure system for double-blind provocation studies investigating possible effects of 2.45 GHz Wi-Fi exposure on human sleep was developed and dosimetrically analyzed. The exposure system includes six simultaneously radiating directional antennas arranged along a circle (radius 0.6 m) around the test subject's head, and enables a virtually uniform head exposure, i.e. without any preferred direction of incidence, during sleep. The system is fully computer-controlled and applies a real wireless local area network (WLAN) signal representing different transmission patterns as expected in real WLAN scenarios, i.e. phases of “beacon only” as well as phases of different data transmission rates. Sham and verum are applied in a double-blind crossover study design and all relevant exposure data, i.e. forward and reverse power at all six antenna inputs, are continuously recorded for quality control. For a total antenna input power (sum of all antennas) of 220 mW, typical specific absorption rate (SAR) in cortical brain regions is approximately 1–2 mW/kg (mass average SAR over respective brain region), which can be seen as a realistic worst-case exposure level in real WLAN scenarios. Taking into account variations of head positions during the experiments, the resulting exposure of different brain regions may deviate from the given average SAR levels up to 10 dB. Peak spatial 10 g average SAR in all brain and all head tissues is between 1.5–3.5 and 10.4–25 mW/kg, respectively. Bioelectromagnetics. © 2020 Bioelectromagnetics Society. 相似文献
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This paper investigates social-environmental factors contributing to differential ethnobotanical expertise among children
in Rarámuri (Tarahumara) communities in Chihuahua, Mexico, to explore processes of indigenous ecological education and epistemologies
of research. One hundred and four children from two schools (one with a Ráramuri knowledge curriculum and one without) were
interviewed about their knowledge of 40 useful plants. Overall, children showed less ethnobotanical expertise than expected
and a great deal of variability by age, though most shared knowledge of a core set of culturally and ecologically salient
plants. No significant difference was found between girls’ and boys’ knowledge. The overall use-knowledge scores were almost
twice as high as naming scores (mean of 40% vs. 24.4%). This supports the conclusion that use-context is more culturally relevant,
salient or easier for children to remember than names. The social–environmental factors significant in predicting levels of
plant knowledge among children were whether a child attended a Rarámuri or Spanish-instruction school, and, to a lesser extent,
age. However, these effects were not strong, and individual variability in expertise is best interpreted using ethnographic
knowledge of each child’s family and personal history, leading to a model of ethnobotanical education that foregrounds experiential
learning and personal and family interest in useful plants. Though overall plant knowledge may be lower among children today
compared to previous generations, a community knowledge structure seems to be reproduced in which a few individuals in each
age cohort show great proficiency, and children make the same kinds of mistakes and share specialized names for plants. 相似文献
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A Perspective on the History and Evolution of an Oceans and Human Health “Metadiscipline” in the USA
We review recent history and evolution of Oceans and Human Health programs and related activities in the USA from a perspective within the Federal government. As a result of about a decade of support by the US Congress and through a few Federal agencies, notably the National Science Foundation, National Institute of Environmental Health Sciences, and National Ocean and Atmospheric Administration, robust Oceans and Human Health (OHH) research and application activities are now relatively widespread, although still small, in a number of agencies and academic institutions. OHH themes and issues have been incorporated into comprehensive federal ocean research plans and are reflected in the new National Ocean Policy enunciated by Executive Order 13547. In just a decade, OHH has matured into a recognized “metadiscipline,” with development of a small, but robust and diverse community of science and practice, incorporation into academic educational programs, regular participation in ocean and coastal science and public health societies, and active engagement with public health decision makers. In addition to substantial increases in scientific information, the OHH community has demonstrated ability to respond rapidly and effectively to emergency situations such as those associated with extreme weather events (e.g., hurricanes, floods) and human-caused disasters (e.g., the Deep Water Horizon oil spill). Among many other things, next steps include development and implementation of agency health strategies and provision of specific services, such as ecological forecasts to provide routine early warnings for ocean health threats and opportunities for prevention and mitigation of these risks. 相似文献
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Adrian Fianu Léa Bourse Nadège Naty Nathalie Le Moullec Beno?t Lepage Thierry Lang Fran?ois Favier 《PloS one》2016,11(1)
In type 2 diabetes (T2D) prevention research, evidence for maintenance of risk factor reduction after three years of follow-up is needed. The objective of this study was to evaluate the long-term effectiveness of a combined lifestyle intervention aiming at controlling body weight (BW) and waist circumference (WC) in non-diabetic, overweight/obese adults living in a low socio-economic community. On Reunion Island, 445 adults living in deprived areas, aged 18–40 and at high-risk for T2D, were included in an intervention versus control trial for primary prevention (2001–2002). The intervention promoted a healthy diet and moderate regular physical activity, through actions strengthening individuals or community and improving living conditions. The control group received a one-shot medical information and nutritional advices. After the end of the trial (2003), 259 of the subjects participated in a follow-up study (2010–2011). The outcomes were the nine-year changes from baseline in BW, body mass index (BMI) and WC measurements, separately. Statistical analyses were performed on an intention-to-treat basis, using available and imputed datasets. At inclusion, T2D risk factors were prevalent: family history of diabetes in first-degree relatives (42%), women with a personal history of gestational diabetes (11%), total obesity (43%, median BMI 29.1 kg/m²) and central obesity (71%). At follow-up, the adjusted effect on imputed dataset was significant for WC -2.4 cm (95% confidence interval: -4.7 to -0.0 cm, p = 0.046), non-significant for BW -2.2 kg (-4.6 to +0.2 kg, p = 0.073) and BMI -0.81 kg/m² (-1.69 to +0.08 kg/m², p = 0.074). A specific long-term effect was the increased likelihood of reduction in adiposity: BW loss, BMI reduction, and WC reduction were more frequent in the intervention group. In the context of low socio-economic communities, our data support the assumption of long-term effect of lifestyle interventions targeting total obesity and central obesity two major drivers of T2D. 相似文献
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Kiyoshi Ando Shigeru Obayashi Yuji Nagai Arata Oh-Nishi Takafumi Minamimoto Makoto Higuchi Takashi Inoue Toshio Itoh Tetsuya Suhara 《PloS one》2012,7(10)
Background
Positron Emission Tomography (PET) measurement was applied to the brain of the common marmoset, a small primate species, treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The marmoset shows prominent Parkinson’s disease (PD) signs due to dopaminergic neural degeneration. Recently, the transgenic marmoset (TG) carrying human PD genes is developing. For phenotypic evaluations of TG, non-invasive PET measurement is considered to be substantially significant. As a reference control for TG, the brain of the MPTP-marmoset as an established and valid model was scanned by PET. Behavioral analysis was also performed by recording locomotion of the MPTP-marmoset, as an objective measure of PD signs.Methodology/Principal Findings
Marmosets received several MPTP regimens (single MPTP regimen: 2 mg/kg, s.c., per day for 3 consecutive days) were used for PET measurement and behavioral observation. To measure immobility as a central PD sign, locomotion of marmosets in their individual living cages were recorded daily by infrared sensors. Daily locomotion counts decreased drastically after MPTP regimens and remained diminished for several months or more. PET scan of the brain, using [11C]PE2I as a ligand of the dopamine (DA) transporter, was performed once several months after the last MPTP regimen. The mean binding potential (BPND) in the striatum (putamen and caudate) of the MPTP-marmoset group was significantly lower than that of the MPTP-free control group (n = 5 for each group). In the MPTP-marmosets, the decrease of BPND in the striatum closely correlated with the decrease in locomotion counts (r = 0.98 in putamen and 0.91 in caudate).Conclusion/Significance
The present characterization of neural degeneration using non-invasive PET imaging and of behavioral manifestation in the MPTP marmoset mimics typical PD characteristics and can be useful in evaluating the phenotype of TG marmosets being developed. 相似文献10.
Lirong Wang Anthony J. Santella Ruizhe Huang Lingling Kou Lijuan You Xiaona Zhang Shu Wang Jingyao Wang Longfei Gao Juan Yin Guihua Zhuang 《PloS one》2015,10(3)
Introduction
China is considered a country of low HIV prevalence (780,000 people living with HIV), however, HIV infections among high-risk populations continue to grow at alarming rates. Voluntary Counseling and Testing services were first implemented in 2003, and oral rapid HIV testing (ORHT) began in 2012. Dentists, as oral health experts, would be well placed to conduct ORHT. We assessed willingness of dentists to undertake ORHT in their clinical practice.Methods
A cross-sectional, paper-based survey of dentists from the Xi’an region of China was conducted from April to June 2013. Dentists were recruited from Shaanxi Stomatological Association using a stratified sampling methodology. A 40-item survey was used to measure knowledge of HIV, attitudes toward people living with HIV and willingness to conduct ORHT.Results
477 dentists completed the survey with a mean HIV knowledge test score of 13.2/18 (SD 1.9). If made available in the dental setting, 276 (57.9%) preferred to use blood to diagnose HIV, only 190 (39.8%) preferred saliva or both. Four hundred and thirty-five (91.2%) thought that ORHT was needed in dental clinics. Female dentists felt more accepting of ORHT than males (93.8% vs. 87.8%; χ2=5.145; p<0.05). 42.6% of the participants who responded thought that lack of education on ORHT for dentists was the most urgent problem to solve for ORHT, 144 (31.3%) thought that lack of support for ORHT from patients was the most urgent problem. There was statistically significant difference among dental hospital, dentistry and department of dentistry (χ2=24.176; p<0.05).Conclusions
The majority of Chinese dentists thought that ORHT was needed in the dental setting. Providing opportunities for dentists and dental students to learn about HIV testing guidelines and practices is needed as well as feasibility and implementation science research. 相似文献11.
William J. Davies Guzel Kudoyarova Wolfram Hartung 《Journal of Plant Growth Regulation》2005,24(4):285-295
In this article we review evidence for a variety of long-distance signaling pathways involving hormones and nutrient ions
moving in the xylem sap. We argue that ABA has a central role to play, at least in root-to-shoot drought stress signaling
and the regulation of functioning, growth, and development of plants in drying soil. We also stress the importance of changes
in the pH of the leaf cell apoplast as influenced both by edaphic and climatic variation, as a regulator of shoot growth and
functioning, and we show how changes in xylem and apoplastic pH can affect the way in which ABA regulates stomatal behavior
and growth. The sensitivity to drought of the pH/ABA sensing and signaling mechanism is emphasized. This allows regulation
of plant growth, development and functioning, and particularly shoot water status, as distinct from stress lesions in growth
and other processes as a reaction to perturbations such as soil drying. 相似文献
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Andrzej Bunio Renata Szygula Slawomir Tubek Grzegorz Krasowski 《Biological trace element research》2010,136(2):149-156
Environmental factors significantly influence the incidence and course of metabolic syndrome diseases such as diabetes and
obesity. The content of elements in rainwater is an indirect indicator of their presence in dust suspended in the air. In
this paper we present the relationships between the content of selected elements in rainwater and hospitalization frequencies
due to diabetes (E10–E13) and obesity (E66). It was assumed that the hospitalization frequency could be taken as a measure
of deterioration of the metabolic process in the course of diabetes and its complications. The observations concerned the
population of Opole Voivodeship, Poland (one million inhabitants), distributed in small communities of 44,000 to 151,000 inhabitants
during the years 2000–2002. In cases of diabetes E10–E13 for all subjects relevant correlation indicators were found for chromium
(r = 0.71), cadmium (r = 0.65), and lead (r = 0.66). Borderline relevance was seen for copper (r = 0.57) and zinc (r = 056). For diabetic men the statistically relevant correlations were chromium (r = 0.79), lead (r = 0.77), cadmium (r = 0.74), copper (r = 0.70), chloride (r = 0.69), zinc (r = 0.68), and iron (r = 0.64). For women the only relevant correlations were chromium (r = 0.62) and cadmium (r = 0.55). No significant correlations were found in obese individuals of both sexes. 相似文献
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Yuko Yoshimura Mitsuru Kikuchi Sanae Ueno Eiichi Okumura Hirotoshi Hiraishi Chiaki Hasegawa Gerard B. Remijn Kiyomi Shitamichi Toshio Munesue Tsunehisa Tsubokawa Haruhiro Higashida Yoshio Minabe 《PloS one》2013,8(11)
Optimal brain sensitivity to the fundamental frequency (F0) contour changes in the human voice is important for understanding a speaker’s intonation, and consequently, the speaker’s attitude. However, whether sensitivity in the brain’s response to a human voice F0 contour change varies with an interaction between an individual’s traits (i.e., autistic traits) and a human voice element (i.e., presence or absence of communicative action such as calling) has not been investigated. In the present study, we investigated the neural processes involved in the perception of F0 contour changes in the Japanese monosyllables “ne” and “nu.” “Ne” is an interjection that means “hi” or “hey” in English; pronunciation of “ne” with a high falling F0 contour is used when the speaker wants to attract a listener’s attention (i.e., social intonation). Meanwhile, the Japanese concrete noun “nu” has no communicative meaning. We applied an adaptive spatial filtering method to the neuromagnetic time course recorded by whole-head magnetoencephalography (MEG) and estimated the spatiotemporal frequency dynamics of event-related cerebral oscillatory changes in beta band during the oddball paradigm. During the perception of the F0 contour change when “ne” was presented, there was event-related de-synchronization (ERD) in the right temporal lobe. In contrast, during the perception of the F0 contour change when “nu” was presented, ERD occurred in the left temporal lobe and in the bilateral occipital lobes. ERD that occurred during the social stimulus “ne” in the right hemisphere was significantly correlated with a greater number of autistic traits measured according to the Autism Spectrum Quotient (AQ), suggesting that the differences in human voice processing are associated with higher autistic traits, even in non-clinical subjects. 相似文献
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Inka Stock 《Ethnic and racial studies》2013,36(9):1577-1595
By describing the everyday lives of African migrant mothers and their children in Morocco, this paper highlights how migration and ‘immobility’ in so-called ‘transit countries’ are gendering and gendered experiences. Relying on migrants' narratives, the paper demonstrates how migrants' transitions to motherhood create both specific and gendered spaces for agency and particular and gendered constraints upon agency that shape women migrants' mobility dynamics in space and time. 相似文献
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Michael T. Treadway Joshua W. Buckholtz Ashley N. Schwartzman Warren E. Lambert David H. Zald 《PloS one》2009,4(8)
Background
Of the putative psychopathological endophenotypes in major depressive disorder (MDD), the anhedonic subtype is particularly well supported. Anhedonia is generally assumed to reflect aberrant motivation and reward responsivity. However, research has been limited by a lack of objective measures of reward motivation. We present the Effort-Expenditure for Rewards Task (EEfRT or “effort”), a novel behavioral paradigm as a means of exploring effort-based decision-making in humans. Using the EEfRT, we test the hypothesis that effort-based decision-making is related to trait anhedonia.Methods/Results
61 undergraduate students participated in the experiment. Subjects completed self-report measures of mood and trait anhedonia, and completed the EEfRT. Across multiple analyses, we found a significant inverse relationship between anhedonia and willingness to expend effort for rewards.Conclusions
These findings suggest that anhedonia is specifically associated with decreased motivation for rewards, and provide initial validation for the EEfRT as a laboratory-based behavioral measure of reward motivation and effort-based decision-making in humans. 相似文献18.
Slawomir Tubek Andrzej Bunio Renata Szyguła Grzegorz Krasowski 《Biological trace element research》2010,138(1-3):1-7
The elemental composition of rainwater is a suitable indirect indicator of the presence of chemical elements in airborne dust. As such, rainwater is considered a suitable monitor for environmental or natural pollution. The yearly content of chemical elements in rainwater may be considered a good indicator for determining the influence of these environmental factors on human body. We decided to investigate the relationship between chemical elements in rainwater and the frequency of hospitalizations for atrial fibrillation (I48, ICD10) on the population of the region of Opole Voivodship, Poland during the years 2000–2002. The voivodship or province has a population of one million and is divided into 12 counties that have between 44,000 and 151,000 inhabitants. We calculated the yearly average number of hospitalizations by reasons of atrial fibrillation per 10,000 inhabitants in particular counties. The average content of the chosen chemical elements in kilograms per hectare per year was calculated for each county individually and the data evaluated by means of Spearman’s correlation coefficient. There is a high positive correlation between chromium in rainwater and hospital admissions for atrial fibrillation (r?=?0.62) and mild positive correlation with cadmium (r?=?0.57), lead (r?=?0.57), zinc (r?=?0.50), and chloride (r?=?0.48). There are no significant differences between male and female patients. The biological activities of these elements, which may include enhanced adrenergic stimulation, remodeling of calcium or other ion channels, or the cytotoxic effects of hexavalent chromium may explain the positive correlations here reported. 相似文献
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Slawomir Tubek Andrzej Bunio Renata Szyguła Grzegorz Krasowski 《Biological trace element research》2011,140(3):253-261
The relationship between chemical elements in rainwater and the frequency of hospitalizations for gastric and duodenal peptic ulcers was studied on the population of the province (Voivodship) of Opole, Poland, during the years 2000–2002. There is a high positive correlation between hospitalized cases of gastric peptic ulcers with chromium in rainwater (r = 0.71), cadmium (r = 0.63), and lead (r = 0.70). Mild positive correlations were found with zinc (r = 0.55), copper (r = 0.56), iron (r = 0.57), chloride (r = 0.60), and sulfate (r = 0.52). These correlations were higher on men, suggesting that there are gender correlations involved. In duodenal peptic ulcers, we observed a high positive correlation between chromium in rainwater and hospitalized cases (r = 0.61) and mild positive correlations with lead (r = 0.57), copper (r = 0.52), and cadmium (r = 0.51). Significant gender differences were not found. These positive correlations may be due to the biological activity of the elements, such as their cytotoxic activity, enhanced local adrenergic stimulation on mucosal vasculature, ion channel (mainly calcium channels) remodeling, and, for example promoting infection by Helicobacter pylori. 相似文献