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1.
We compared twins to their gender-matched singleton classmates in peer-assessed behavioral adjustment. Our samples include 1874 11- to 12-year-old Finnish twins (687 monozygotic, MZ; 610 same-sex dizygotic, SSDZ; 577 opposite-sex dizygotic, OSDZ) and their 23,200 non-twin classmates. Data were collected using a 30-item Multidimensional Peer Nomination Inventory containing three factors and their subscales. We found twin-singleton differences: classmates rated twin girls and boys higher than gender-matched singletons in Adaptive Behaviors (constructive, compliant, and socially active behavior), and those effects were particularly evident among OSDZ twins for assessments of social interaction, popularity, and leadership. We found no evidence that individual twins differ from singletons in Externalizing (hyperactivity-impulsivity, inattention, aggression) or Internalizing Problem Behaviors (depressive symptoms, social anxiety). Nor did we find systematic differences between MZ and SSDZ twins. Among both twins and singletons, boys exceeded girls in Externalizing, and girls exceeded boys in Internalizing Problem Behaviors. Results suggest that a twinship forms a positive developmental environment for socioemotional behavior, particularly among OSDZ twins.  相似文献   

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A five-session laboratory project was designed to familiarize or increase the laboratory proficiency of biology students and others with techniques and instruments commonly used in molecular biology research laboratories and industries. In this project, the EZ-Tn5 transposon is used to generate and screen a large number of cells transformed with mutagenized pGLO plasmid. EZ-Tn5 carries the kanamycin resistance (Kan(R)) gene, and the pGLO plasmid carries the β-lactamase gene for ampicillin resistance (Amp(R)), the gene encoding green fluorescent protein (GFP) and the arabinose operon repressor (araC). Insertion of the Tn5 transposon into pGLO occurs randomly, and any gene into which it inserts is knocked out. By screening cells transformed with mutagenized pGLO with kanamycin, ampicillin, arabinose and/or for GFP expression in different combinations, pGLO plasmids with mutations in different genes are identified. The locations of these insertions are then mapped approximately by restriction fragment analysis and precisely by sequence analysis of the pGLO plasmid.  相似文献   

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An updated review of the genotoxicity studies with acrylamide is provided. Then, using data from the studies generating quantitative information concerning heritability of genetic effects, an assessment of the heritable genetic risk presented by acrylamide is presented. The review offers a discussion of the reactions and possible mechanisms of genotoxic action by acrylamide and its epoxide metabolite glycidamide. Several genetic risk approaches are discussed, including the parallelogram, direct (actually a modified direct), and doubling dose approaches. Using data from the specific-locus and heritable translocation assays, the modified direct and doubling dose approaches are utilized to quantitate genetic risk. Exposures of male parents to acrylamide via inhalation, ingestion, and dermal routes are also quantitated. With these approaches and measurements and their underlying assumptions concerning extrapolation factors (including germ cell stage specificity, DNA repair variability, locus specificity), number of human loci associated with dominant disease alleles, and spontaneous mutation rates, an assessment of heritable genetic risk for humans is calculated for the three exposure scenarios. The calculated estimates for offspring from fathers exposed to acrylamide via drinking water are up to three offspring potentially affected with induced genetic disease per 108 offspring. Estimates for inhalation or dermal exposures suggest higher risks for induced genetic disease in offspring from fathers exposed in occupational settings.  相似文献   

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Hydrobiologia - The assessment of the Laguna de Bay's changing ecological status is imperative in order to address the growing concern of its possible impact on the suitability of the lake to...  相似文献   

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The involvement of the OECD in managing the validation of the rat uterotrophic assay for endocrine disruptors, and in organising the peer review of the results of this study, has been assessed and compared with the many conclusions and recommendations in several published reports of international workshops on validation, and information in guidance documents, produced by the European Centre for the Validation of Alternative Methods (ECVAM), the US Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) and the OECD itself. It is concluded that the OECD has not followed the recommendations for full transparency and independence of the peer-review process. This is based on the fact that it has published a draft guidance document that differs from the report of a recent OECD workshop on validation, in such a way as to give the OECD the flexibility to fully control the peer-review process and, in so doing, to avoid full transparency. Comparison of the timing of the organisation of workshops by the OECD and the progression of the validation study, together with the fact that a draft test guideline for the assay was written before completion of the peer review, suggest that the OECD has given a higher priority to the expedition of the validation and regulatory acceptance of the uterotrophic assay than it has to good scientific and logistical practice. This severely undermines its credibility in the validation process, so, in order for the OECD to be rightly perceived as an honest broker, it is recommended that the OECD should play no role in the validation of new or revised tests, until after they have been successfully validated, peer reviewed, and endorsed by the appropriate authorities, and are ready for test guideline development. With regard to the on-going OECD validation studies of other in vivo assays for endocrine disruptors, the OECD should take immediate steps to ensure full independence and transparency of their peer review.  相似文献   

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The goal of this laboratory course is to introduce vertebrate developmental biology to undergraduate students, emphasizing both classical and contemporary aspects of this field. During the course, the students combine the use of living Xenopus laevis material with active tutorial participation, with the aim of illustrating how the fertilized egg can generate the diversity of cell types and complexity of pattern seen only a few days later in the embryo. Special emphasis is given to the observation and manipulation of living material. The laboratory course includes a comprehensive analysis of both oogenesis and early development and is divided into two overlapping parts that combine tutorial and practical approaches. The first part is devoted to oogenesis; oocytes are sorted out, allowed to mature in vitro and observed in histological section. In the second part, students perform an in vitro fertilization of Xenopus eggs and a mesoderm and neural induction assay of animal cap explants. Successful induction of the explants is confirmed by morphological, histological and molecular analyses. Finally, the students observe and comment on selected slides to illustrate the organization of the body plan of the amphibian embryo at an early stage of organogenesis.  相似文献   

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Background

While an extensive array of existing evidence-based practices (EBPs) have the potential to improve patient outcomes, little is known about how to implement EBPs on a larger scale. Therefore, we sought to identify effective strategies for scaling up EBPs in primary care.

Methods

We conducted a systematic review with the following inclusion criteria: (i) study design: randomized and non-randomized controlled trials, before-and-after (with/without control), and interrupted time series; (ii) participants: primary care-related units (e.g., clinical sites, patients); (iii) intervention: any strategy used to scale up an EBP; (iv) comparator: no restrictions; and (v) outcomes: no restrictions. We searched MEDLINE, Embase, PsycINFO, Web of Science, CINAHL, and the Cochrane Library from database inception to August 2016 and consulted clinical trial registries and gray literature. Two reviewers independently selected eligible studies, then extracted and analyzed data following the Cochrane methodology. We extracted components of scaling-up strategies and classified them into five categories: infrastructure, policy/regulation, financial, human resources-related, and patient involvement. We extracted scaling-up process outcomes, such as coverage, and provider/patient outcomes. We validated data extraction with study authors.

Results

We included 14 studies. They were published since 2003 and primarily conducted in low-/middle-income countries (n?=?11). Most were funded by governmental organizations (n?=?8). The clinical area most represented was infectious diseases (HIV, tuberculosis, and malaria, n?=?8), followed by newborn/child care (n?=?4), depression (n?=?1), and preventing seniors’ falls (n?=?1). Study designs were mostly before-and-after (without control, n?=?8). The most frequently targeted unit of scaling up was the clinical site (n?=?11). The component of a scaling-up strategy most frequently mentioned was human resource-related (n?=?12). All studies reported patient/provider outcomes. Three studies reported scaling-up coverage, but no study quantitatively reported achieving a coverage of 80% in combination with a favorable impact.

Conclusions

We found few studies assessing strategies for scaling up EBPs in primary care settings. It is uncertain whether any strategies were effective as most studies focused more on patient/provider outcomes and less on scaling-up process outcomes. Minimal consensus on the metrics of scaling up are needed for assessing the scaling up of EBPs in primary care.

Trial registration

This review is registered as PROSPERO CRD42016041461.
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In order to evaluate whether different DNA extraction procedures can affect estimates of benthic bacterial diversity, based on 16S rRNA gene terminal restriction fragment length polymorphism (T-RFLP) fingerprinting technique, we compared two in situ lysis procedures (a SDS-based protocol and a commercial kit for DNA recovery) and one cell-extraction protocol on a variety of marine sediments. Despite the two in situ lysis procedures resulted in significantly different DNA yields (highest with the SDS in situ lysis), estimates of bacterial diversity provided a not significantly different ribotype richness, as well as similar values of the Shannon-Wiener (H') and Margalef (d) indices of biodiversity and of evenness (Pielou index, J). Conversely, the cell-extraction procedure for DNA extraction resulted always in a significantly lower ribotype richness and diversity. The analysis of similarities (anosim) among the T-RFLP electropherograms allowed concluding that ribotypes composition did not change significantly using different protocols. However, the analysis of beta-diversity (turnover diversity) revealed that a large number of ribotypes was observed exclusively with one of the three protocols utilized. When unshared ribotypes from in situ lysis and cell extraction were pooled together, total ribotype richness resulted much higher (up to 80%). Our results indicate that estimates of ribotype diversity based on a single protocol of DNA extraction can significantly underestimate the total number of bacterial ribotypes present in the benthic domain. We recommend that future studies will not only integrate different DNA extraction procedures, but also will explore the possibility of integrating two or more different genetic markers in order to increase our ability to detect the actual bacterial diversity in environmental samples.  相似文献   

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A series of eight single-subject experiments were performed to test the feasibility of using a stimulus control procedure to teach subjects to control heart rate in the absence of feedback and outside of the laboratory. Four of the six subjects who completed the experiments were able to demonstrate increases in heart rate of from 15 to 35 beats per minute without the assistance of feedback and outside of the laboratory. These increases were consistently produced over six daily sessions. Through the use of a systematic replication series of experiments, it was possible tentatively to rule out age, sex, and basal heart rate of subject, as well as type of previous feedback training and number of prior training sessions, as accounting for the differential success.  相似文献   

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The amount of risk animals perceive in a given circumstance (i.e. their degree of 'fear') is a difficult motivational state to study. While many studies have used flight initiation distance as a proxy for fearfulness and examined the factors influencing the decision to flee, there is no general understanding of the relative importance of these factors. By identifying factors with large effect sizes, we can determine whether anti-predator strategies reduce fear, and we gain a unique perspective on the coevolution of predator and anti-predator behaviour. Based on an extensive review and formal meta-analysis, we found that predator traits that were associated with greater risk (speed, size, directness of approach), increased prey distance to refuge and experience with predators consistently amplified the perception of risk (in terms of flight initiation distance). While fish tolerated closer approach when in larger schools, other taxa had greater flight initiation distances when in larger groups. The presence of armoured and cryptic morphologies decreased perception of risk, but body temperature in lizards had no robust effect on flight initiation distance. We find that selection generally acts on prey to be sensitive to predator behaviour, as well as on prey to modify their behaviour and morphology.  相似文献   

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Yati A  Dey S 《BioTechniques》2011,51(5):347-348
While several software programs exist to count bacterial colonies on a Petri plate, no suitable solution is available for quick and reliable enumeration of small, live insects. We have written a program called FlyCounter that can obtain counts from images, even if insects are highly clumped in space. We also describe a simple and inexpensive system for anesthetizing and capturing high-quality images of the small insects. Taken together, our process is fast, fully automatic, and has a low percentage of error (~1%-4% on average). Although we have tested our software on fruit flies, it should be simple to extend to other organisms of similar size.  相似文献   

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<正>Dear Editors,Ebola virus disease(EVD)is an acute,serious and fatal illness caused by the Ebola virus.EVD was first identified in 1976 during two simultaneous outbreaks,one in Nzara,Sudan,and the other in Yambuku,Democratic Republic of Congo[1].The latter o ccurred in a village near the Ebola River,from which the disease takes its name.Since its  相似文献   

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Western India experiences arid to dry subhumid ecoclimate. Aridity increases from east to west to the Great Indian Desert or Thar Desert. The desert economy is animal based and goats are the most common livestock; density of goats increases with increase in aridity. There are large morphological variations in goats warranting the recognition of population differences throughout the region. The present investigations were therefore undertaken to see whether there are population differences and, if so, to establish the populations on a sound ecological basis. Eleven physical measurements of the animals were made in the fields of western India in a total of 518 animals (255 adults). Five populations were initially segregated by means of a scatter diagram. Population differences were confirmed by mathematical treatments using analysis of variance (one-way and two-way) and Students-Newman-Keuls test, which yields a critical comparison among means. Discriminant analysis was used to determine whether the goat populations differed significantly between the five climo-edaphic-vegetational zones. Each population was designated according to the locality having the greatest density as: POP1Ku, POP2Sa, POP3Jh, POP4Ga, POP5Pa. The five populations occurring in distinct climo-edaphic-vegetational zones or ecological niches in western India may be referred to as ecotypes.  相似文献   

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A reliable marking technique was needed for a mark–release–recapture experiment with adults of Diabrotica speciosa (Germar). Four marking techniques, acrylic paint (spattered or brushed on the surface of the insect); and fluorescent pigments (dusted on surfaces or mixed with diet to produce an ingested marker), were tested. Fluorescent pigment durability for the dusting and ingested techniques was evaluated for laboratory conditions and under simulated field conditions. The impact of the techniques on beetle survival was also assessed. Both acrylic paint techniques caused mobility problems in the beetles, and neither technique lasted for more than 48 h. Both fluorescent pigment techniques were more reliable, but the dusting technique showed a significantly higher mortality than the control, and duration variations between laboratory and field conditions. Use of fluorescent pigments added to the diet was the most reliable technique. This technique allowed the manipulation of the marking period, and provided reliable timing of marker persistence in the field.  相似文献   

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The harmful outcomes of nicotine self administration have been the focus of sustained global health education campaigns that have targeted tobacco smoking and to a lesser extent, smokeless tobacco use. 'Smokeless tobacco' infers that the nicotine is not burnt, and administration can be through a range of methods including chewing. The chewing of wild tobacco plants (Nicotiana spp.) is practiced across a broad inland area of Central Australia by traditional Aboriginal groups. Collectively these plants are known by a variety of names - one common name being 'pituri'. This is the first paper to examine the historical literature and consider the linkage between pituri use and health outcomes. Using a narrative approach, this paper reviews the literature generated since 1770 surrounding the term pituri and the behaviours associated with its use. The review examines the scientific literature, as well as the diaries and journals of nineteenth century explorers, expedition notes, and early Australian novels to expound the scientific evidence and broaden the sense of understanding related to pituri, particularly the behavioural elements. The evaluation considers the complexities of ethnobotany pertaining to language and distance and the ethnopharmacology of indigenous plant usage. The review compares the use of burnt and smokeless tobacco to pituri and establishes the foundation for research into the clinical significance and health outcomes of pituri use. Additionally, this review provides contemporary information for clinicians providing care for patients who chew pituri.  相似文献   

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