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Although the science of team science is no longer a new field, the measurement of team science and its standardization remain in relatively early stages of development. To describe the current state of team science assessment, we conducted an integrative review of measures of research collaboration quality and outcomes.
Collaboration measures were identified using both a literature review based on specific keywords and an environmental scan. Raters abstracted details about the measures using a standard tool. Measures related to collaborations with clinical care, education, and program delivery were excluded from this review.
We identified 44 measures of research collaboration quality, which included 35 measures with reliability and some form of statistical validity reported. Most scales focused on group dynamics. We identified 89 measures of research collaboration outcomes; 16 had reliability and 15 had a validity statistic. Outcome measures often only included simple counts of products; publications rarely defined how counts were delimited, obtained, or assessed for reliability. Most measures were tested in only one venue.
Although models of collaboration have been developed, in general, strong, reliable, and valid measurements of such collaborations have not been conducted or accepted into practice. This limitation makes it difficult to compare the characteristics and impacts of research teams across studies or to identify the most important areas for intervention. To advance the science of team science, we provide recommendations regarding the development and psychometric testing of measures of collaboration quality and outcomes that can be replicated and broadly applied across studies.
Although animal models and correlational studies support a model of fetal programming as a mechanism in the transmission of risk for psychopathology from parents to children, the experimental studies that are required to empirically test the model with the human prenatal dyad are scarce. With a systematic review and meta-analysis of the literature, we critically examined the evidence regarding the neurobiological and behavioral changes in infants as a function of randomized clinical trials to prevent or reduce maternal depression during pregnancy, treating randomized clinical trials as experiments testing the fetal programming model. Based on 25 articles that met inclusion criteria, we found support for interventions designed to change maternal prenatal mood being associated with changes in offspring functioning, but with a very small effect size. Effect sizes ranged broadly, and were higher for younger children. The findings enhance understanding of putative mechanisms in the transmission of risk from women's prenatal depression to infants’ vulnerabilities to, and early signs of, the development of psychopathology. We note limitations of the literature and suggest solutions to advance understanding of how preventing or treating depression in pregnant women might disrupt the transmission of risk to the infants.
Maltreated children in foster care are at high risk for dysregulated hypothalamus–pituitary–adrenal (HPA) axis functioning and educational difficulties. The present study examined the effects of a short-term school readiness intervention on HPA axis functioning in response to the start of kindergarten, a critical transition marking entry to formal schooling, and whether altered HPA axis functioning influenced children's school adjustment. Compared to a foster care comparison group, children in the intervention group showed a steeper diurnal cortisol slope on the first day of school, a pattern previously observed among nonmaltreated children. A steeper first day of school diurnal cortisol slope predicted teacher ratings of better school adjustment (i.e., academic performance, appropriate classroom behaviors, and engagement in learning) in the fall of kindergarten. Furthermore, the children's HPA axis response to the start of school mediated the effect of the intervention on school adjustment. These findings support the potential for ameliorative effects of interventions targeting critical transitional periods, such as the transition of formal schooling. This school readiness intervention appears to influence stress neurobiology, which in turn facilitates positive engagement with the school environment and better school adjustment in children who have experienced significant early adversity.
Surface sediments (n=85) from a 160-km river-estuarine transect of the Clyde, UK, were analysed for total mercury (Hg), saturated hydrocarbons and unresolved complex mixtures (UCMs) of hydrocarbons. Results show that sediment-Hg concentration ranges from 0.01 to 1.38mgkg–1 (mean 0.20mgkg–1) and a spatial trend in Hg-content low–high–low–high, from freshwater source, to Glasgow, to estuary, is evident. In summary, sediment-Hg content is low in the upper Clyde (mean of 0.05Hg mgkg–1), whereas sediments from the Clyde in urbanised Glasgow have higher Hg concentrations (0.04 to 1.26mgkg–1; mean 0.45mgkg–1), and the inner estuary sediments contain less Hg (mean 0.06mgkg–1). The highest mean sediment Hg (0.65mgkg–1) found in the outer estuary is attributed to historical anthropogenic activities. A significant positive Spearman correlation between Hg and total organic carbon is observed throughout the river estuary (0.86; P<0.001). Comparison with Marine Scotland guidelines suggests that no sites exceed the 1.5mgkg–1 criterion (Action Level 2); 22 fall between 0.25 and 1.5mgkg–1 dry wt. (Action Level 1) and 63 are of no immediate concern (<0.25mgkg–1 dry wt.). Saturated (n-alkane) hydrocarbons in the upper Clyde are of natural terrestrial origin. By contrast, the urbanised Glasgow reaches and outer estuary are characterised by pronounced and potentially toxic UCM concentrations in sediments (380–914mg/kg and 103–247mgkg–1, respectively), suggesting anthropogenic inputs such as biodegraded crude oil, sewage discharge and/or urban run-off.
Sarcomas are solid malignant tumors arising from mesenchymal tissue with distinct clinical and pathological features. They constitute a diverse group of tumors with more than 50 different histological subtypes divided into two broad categories: sarcomas of soft tissues (including fat, muscles, nerves, blood vessels, and other connective tissues) and sarcomas of bones (1, 2). Several classification schemes for sarcoma exist. In general, classification is based on histology with tumors subdivided according to the presumed tissue of origin.
Sarcomas can occur anywhere in the body and at all ages in both men and women. The age of incidence depends, at least in part, on the type as well as the subtype. For example, osteosarcomas tend to develop in young adults while chondrosarcomas are more common in older patients. Sarcomas found within certain organs may be difficult to differentiate from other malignancies; therefore, the true incidence of sarcomas is likely underestimated (3). Collectively, sarcomas are believed to account for approximately 1% of all adult malignancies and 15% of all pediatric malignancies (1). While soft tissue sarcomas are overall more frequent in middle-aged and older adults than in children and young adults, some subtypes such as rhabdomyosarcoma and synovial sarcoma are more common in young patients. Indeed soft tissue sarcomas account for a large proportion of pediatric malignancies, i.e., 7–10%. The incidence of primary bone tumors is approximately one-fifth that of soft tissue sarcomas. However, primary bone tumors also represent a significant percentage of malignancies in patients under the age of 20. Sarcomas are an important cause of death in the 14–29 years age group (4). Even in adults, the number of years of life lost is substantial despite the very low incidence of the disease, because people are often affected during the prime of their life (3).
We aimed to describe the difference in B-vitamin intake and in plasma B-vitamin and homocysteine concentrations before and after folic acid fortification, in relation to dietary patterns.
The Normative Aging Study (NAS) is a longitudinal study on ageing. Between 1961 and 1970, 2280 male volunteers aged 21–80 years (mean 42 years) were recruited. Dietary intake data have been collected since 1987 and assessment of plasma B vitamins and homocysteine was added in 1993.
Boston, Massachusetts, USA.
In the present study, 354 men who had completed at least one FFQ and one measurement of homocysteine, both before and after the fortification period, were included.
Three dietary patterns were identified by cluster analysis: (i) a prudent pattern, with relatively high intakes of fruit, vegetables, low-fat milk and breakfast cereals; (ii) an unhealthy pattern, with high intakes of baked products, sweets and added fats; and (iii) a low fruit and vegetable but relatively high alcohol intake pattern. Dietary intake and plasma concentrations of folate increased significantly (P < 0·05) among all dietary patterns after the fortification period. Homocysteine tended to decrease in supplement non-users and in subjects in the high alcohol, low fruit and vegetable dietary pattern (both P = 0·08).
After fortification with folic acid, folate intake and plasma folate concentration increased significantly in all dietary patterns. There was a trend towards greatest homocysteine lowering in the high alcohol, low fruit and vegetable group.
Hepatitis C virus (HCV) transmission occurs in 0.2%-10% of people after accidental needlestick exposures. However, postexposure prophylaxis is not currently recommended. We sought to determine the safety, tolerability, and acceptance of postexposure prophylaxis with peginterferon alfa-2b in healthcare workers (HCWs) exposed to blood from HCV-infected patients.
Open-label pilot trial of peginterferon alfa-2b for HCV postexposure prophylaxis.
TWO academic tertiary-referral centers.
HCWs exposed to blood from HCV-infected patients were informed of the availability of postexposure prophylaxis. Persons who elected postexposure prophylaxis were given weekly doses of peginterferon alfa-2b for 4 weeks.
Among 2,702 HCWs identified with potential exposures to bloodborne pathogens, 213 (7.9%) were exposed to an HCV antibody-positive source. Of 51 HCWs who enrolled in the study, 44 (86%) elected to undergo postexposure prophylaxis (treated group). Seven subjects elected not to undergo postexposure prophylaxis (untreated group). No cases of HCV transmission were observed in either the treated or untreated group, and no cases occurred in the remaining 162 HCWs who did not enroll in this study. No serious adverse events related to a peginterferon alfa-2b regimen were recorded, but minor adverse events were frequent.
In this pilot study, there was a lower than expected frequency of HCV transmission after accidental occupational exposure. Although peginterferon alfa-2b was safe, because of the lack of HCV transmission in either the treated or untreated groups there is little evidence to support routine postexposure prophylaxis against HCV in HCWs.
The cycloid was an important “new curve” attracting mathematicians' attention in the seventeenth and eighteenth centuries. It turned out to be particularly significant in the study of the behavior of objects falling under the force of gravity: the cycloid is not only the brachistochrone (path of descent in shortest time) but also the tautochrone (path of descent in equal time from any point on the path). New mathematical tools such as the calculus made it possible to apply the study of such curves, and of concepts such as their “evolutes” and “involutes”, to mechanical problems.
The significance of these developments is often lost on students who find them unfamiliar and remote. The story of Huygens' cycloid pendulum clock is an intriguing, easy-to-understand application of these mathematical ideas to a very practical problem. And it supplies a hands-on construction project that reinforces students' comprehension of how the cycloid and evolutes of curves actually work.
Huygens and the cycloid
Timekeeping problems and the tautochrone curve
In the middle of the seventeenth century, the scientific revolution and nautical discovery were in full swing. The expansion of trade and colonization meant an increasing need for accuracy in determining longitude at sea. An accurate clock would solve the problem of measuring time differences precisely enough to determine longitude; it would also be useful in many scientific experiments. The trouble was that clockmaking technology at that time wasn't developed enough to produce a sufficiently accurate clock.
Substance use is implicated in the cause and course of psychosis.
To characterise substance and alcohol use in an epidemiologically representative treatment sample of people experiencing a first psychotic episode in south Cambridgeshire.
Current and lifetime substance use was recorded for 123 consecutive referrals to a specialist early intervention service. Substance use was compared with general population prevalence estimates from the British Crime Survey.
Substance use among people with first-episode psychosis was twice that of the general population and was more common in men than women. Cannabis abuse was reported in 51% of patients (n=62) and alcohol abuse in 43% (n=53). More than half (n=68, 55%) had used Class A drugs, and 38% (n=43) reported polysubstance abuse. Age at first use of cannabis, cocaine, ecstasy and amphetamine was significantly associated with age at first psychotic symptom.
Substance misuse is present in the majority of people with first-episode psychosis and has major implications for management. The association between age at first substance use and first psychotic symptoms has public health implications.
In this paper we present for the first time the use of the Si2H6/H2/Cl2 chemistry for selective silicon epitaxy in a rapid thermal CVD reactor. Depositions were carried out in an ultra-high vacuum rapid thermal chemical vapor deposition (UHV-RTCVD) system designed and constructed at North Carolina State University. Experiments were performed over a temperature range of 650°C to 850°C and over a pressure range of 22 to 25 mTorr using a flow rate 100 sccm of 10% Si2H6 in H2 and 0 to 10 sccm of Cl2. Deposited layer thicknesses were evaluated using a combination of interferometry and profilometry. Without Cl2 over the range of 650°C to 850°C, the growth rate is approximately constant at 160 nm/min. exhibiting a weak dependence on temperature. A clear advantage of Si2H6 is that high growth rates compatible with single wafer manufacturing can be obtained at very low pressures thus minimizing the introduction of contaminants by the process gases. With the addition of C12, the growth rate is suppressed at temperatures below 800°C, but, at 800°C and above, it is affected only slightly for Cl2 flow rates below 5 sccm. As the Cl2 flow rate is increased past 5 sccm, the growth rate at higher temperatures becomes a strong function of Si2H6:Cl2 ratio. Excellent selectivity with respect to patterned SiO2 and Si3N4 was obtained over the entire Cl2 flow rate range suggesting that even lower Cl levels may be sufficient for selective deposition. This implies that selectivity can be obtained with Si:Cl ratios much lower than those introduced by the more commonly used SiH2Cl2 chemistry. Furthermore, because Si2H6 can provide high growth rates at very low pressures, the total partial pressures of Cl2 and resulting chlorinated species can be significantly lower than typically required for selectivity. Our results indicate that C12 successfully enhances selectivity and yields highly selective depositions for process durations well within the practical limits of single wafer manufacturing.
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