bluuebunny/crossref_metadata_2025 huggingface dataset:
Post‐extraction mesio‐distal gap reduction assessment by confocal laser scanning microscopy – a clinical 3‐month follow‐up study
Authors: García‐Herraiz Ariadna , Silvestre Francisco Javier , Leiva‐García Rafael , Crespo‐Abril Fortunato , García‐Antón José
Published: February 2017

Aim

The aim of this 3‐month follow‐up study is to quantify the reduction in the mesio‐distal gap dimension (MDGD) that occurs after tooth extraction through image analysis of three‐dimensional images obtained with the confocal laser scanning microscopy (CLSM) technique.

Materials and Methods

Following tooth extraction, impressions of 79 patients 1 month and 72 patients 3 months after tooth extraction were obtained. Cast models were processed by CLSM, and MDGD changes between time points were measured.

Results

The mean mesio‐distal gap reduction 1 month after tooth extraction was 343.4 μm and 3 months after tooth extraction was 672.3 μm. The daily mean gap reduction rate during the first term (between baseline and 1 month post‐extraction measurements) was 10.3 μm/day and during the second term (between 1 and 3 months) was 5.4 μm/day.

Conclusions

The mesio‐distal gap reduction is higher during the first month following the extraction and continues in time, but to a lesser extent. When the inter‐dental contacts were absent, the mesio‐distal gap reduction is lower. When a molar tooth is extracted or the distal tooth to the edentulous space does not occlude with an antagonist, the mesio‐distal gap reduction is larger. The consideration of mesio‐distal gap dimension changes can help improve dental treatment planning.
Relationship between renal function and periodontal disease in community‐dwelling elderly women with different genotypes
Authors: Yoshihara Akihiro , Sugita Noriko , Iwasaki Masanori , Wang Yanming , Miyazaki Hideo , Yoshie Hiromasa , Nakamura Kazutoshi
Published: February 2017

Objectives

The aim of this study was to examine the association between periodontal disease and renal function in elderly women with different genotypes.

Material and Methods

A total of 332 postmenopausal never‐smoking women were analysed. Poor renal function was defined as serum cystatin C > 0.91 mg/l. Periodontal disease markers such as periodontal inflamed surface area (PISA) were evaluated. Selected variables, including PISA quartile, body mass index (BMI), HbA1C and age in Arg allele carriers and non‐carriers based on the beta‐3 adrenergic receptor, or between Ala allele carriers and non‐carriers based on peroxisome proliferator‐activated receptor gamma, were analysed using multiple logistic regression analysis.

Results

The odds ratios of serum cystatin C level and PISA (fourth quartile) were significantly positive for both Arg (2.52; p = 0.035) and Ala allele non‐carriers (2.36; p = 0.021). A significant association was also found between serum cystatin C level and BMI for both Arg (1.18; p = 0.001) and Ala allele non‐carriers (1.12; p = 0.003).

Conclusion

The results of this study suggest that periodontal inflammation might be associated with renal function. Furthermore, in both the Arg and Ala allele non‐carriers, the associations between BMI and PISA for renal function became stronger.
Perioperative hypothermia during hip fracture surgery: An observational study
Authors: Gurunathan Usha , Stonell Christopher , Fulbrook Paul
Published: February 2017

Rationale

Elderly patients are at high risk of accidental perioperative hypothermia. The primary objective of this study was to measure the changes in body temperature and the incidence of hypothermia in elderly patients undergoing hip fracture surgery.

Methods

We conducted a prospective observational study on all adult patients undergoing surgery for fractured neck of femur between December 2013 and July 2014. We monitored their temperatures in different perioperative areas at multiple time points and also noted the warming methods used.

Results

Eighty‐seven patients were included in this study. A significant drop in body temperature (0.7°C, 95% CI: 0.6‐0.9, P < 0.001) occurred from their arrival at the operating theatre until their arrival at the recovery room. A significant drop of 0.2°C (95% CI: 0.1‐0.4, P < 0.001) was observed at the holding bay area. One third of the patients were noted to be hypothermic when they arrived at the recovery room.

Conclusion

These results indicate that despite the use of active warming methods for most patients, significant hypothermia is still an issue amongst elderly patients undergoing hip fracture surgery. Further improvement is necessary to prevent hypothermia in this high‐risk group of patients.
BISAP, RANSON, lactate and others biomarkers in prediction of severe acute pancreatitis in a European cohort
Authors: Valverde‐López Francisco , Matas‐Cobos Ana M , Alegría‐Motte Carlos , Jiménez‐Rosales Rita , Úbeda‐Muñoz Margarita , Redondo‐Cerezo Eduardo
Published: February 2017

Background and Aim

The study aims to assess and compare the predicting ability of some scores and biomarkers in acute pancreatitis.

Methods

We prospectively collected data from 269 patients diagnosed of acute pancreatitis, admitted to Virgen de las Nieves University Hospital between June 2010 and June 2012. Blood urea nitrogen (BUN), C‐reactive protein, and creatinine were measured on admission and after 48 h, lactate and bedside index for severity acute pancreatitis (BISAP) only on admission and RANSON within the first 48 h. Definitions from 2012 Atlanta Classification were used. Area under the curve (AUC) was calculated for each scoring system for predicting severe acute pancreatitis (SAP), mortality, and intensive care unit (ICU) admission, obtaining optimal cut‐off values from the receiver operating characteristic curves.

Results

Eight (3%) patients died, 17 (6.3%) were classified as SAP, and 10 (3.7%) were admitted in ICU. BISAP was the best predictor on admission for SAP, mortality, and ICU admission with an AUC of 0.9 (95% CI 0.83–0.97); 0.97 (95% CI 0.95–0.99); and 0.89 (95% CI 0.79–0.99), respectively. After 48 h, BUN 48 h was the best predictor of SAP (AUC = 0.96 CI: 0.92–0.99); BUN 48 h and BISAP were the best predictors for mortality (AUC = 0.97 CI: 0.95–0.99) and creatinine 48 h for ICU admission (AUC = 0.96 CI: 0.92–0.99). Lactate showed an AUC of 0.79 (CI: 0.71–0.88), 0.87 (CI: 0.78–0.96), and 0.77 (CI: 0.67–0.87) for SAP, mortality, and ICU admission, respectively. All parameters were predictors for SAP, mortality, and ICU admission, but C‐reactive protein on admission was only a significant predictor of SAP.

Conclusion

Bedside index for severity acute pancreatitis is a good predictive system for SAP, mortality, and ICU admission, being useful for triaging patients for ICU management. Lactate could be useful for developing new scores.
Questioning skills of clinical facilitators supporting undergraduate nursing students
Authors: Phillips Nicole M , Duke Maxine M , Weerasuriya Rona
Published: February 2017

Aims and objectives

To report on a study investigating questioning skills of clinical facilitators who support the learning of undergraduate nursing students.

Background

The ability to think critically is integral to decision‐making and the provision of safe and quality patient care. Developing students’ critical thinking skills is expected of those who supervise and facilitate student learning in the clinical setting. Models used to facilitate student learning in the clinical setting have changed over the years with clinicians having dual responsibility for patient care and facilitating student learning. Many of these nurses have no preparation for the educative role. This study adapted a comparative study conducted over fifteen years ago.

Design

Descriptive online survey including three acute care patient scenarios involving an undergraduate nursing student. Participants were required to identify the questions they would ask the student in relation to the scenario.

Methods

A total of 133 clinical facilitators including clinical teachers, clinical educators and preceptors from five large partner healthcare organisations of one Australian university participated.

Results

The majority of questions asked were knowledge questions, the lowest category in the cognitive domain requiring only simple recall of information. Facilitators who had undertaken an education‐related course/workshop or formal qualification asked significantly more questions from the higher cognitive level.

Conclusion

The study provides some evidence that nursing facilitators in the clinical setting ask students predominantly low‐level questions. Further research is needed to identify strategies that develop the capacity of facilitators to ask higher level cognitive questions.

Relevance to clinical practice

Clinical facilitators should undertake targeted education that focuses on how to frame questions for students that demand application, analysis, synthesis and evaluation.
Shared care requires a shared vision: communities of clinical practice in a primary care setting
Authors: Young Jessica , Egan Tony , Jaye Chrystal , Williamson Martyn , Askerud Anna , Radue Peter , Penese Maree
Published: February 2017

Aims and objectives

To understand how a vision of care is formed and shared by patients and the primary care professionals involved in their care.

Background

To achieve the best health outcomes, it is important for patients and those who care for them to have a mutual understanding about what is important to the patient in their everyday life and why, and what care is necessary to realise this vision. Shared or team care does not necessarily translate to a consistent and integrated approach to a patient's care. An individual patient's care network of clinical and lay participants can be conceptualised as the patient's own ‘Community of Clinical Practice’ of which they are the central member.

Design

Working alongside a long‐term conditions nursing team, we conducted a focused ethnography of nine ‘Communities of Clinical Practice’ in one general practice setting.

Method

Participant observation, in‐depth qualitative interviews with 24 participants including nine patients, and the patients’ medical records. Data were analysed using a template organising style.

Findings

Primary care professionals' insight into a patient's vision of care evolves through a deep knowing of the patient over time; this is shared between ‘Community of Clinical Practice’ members, frequently through informal communication and realised through respectful dialogue. These common values – respect, authenticity, autonomy, compassion, trust, care ethics, holism – underpin the development of a shared vision of care.

Conclusions

A patient's vision of care, if shared, provides a focus around which ‘Community of Clinical Practice’ members cohere. Nurses play an important role in sharing the patient's vision of care with other participants.

Relevance to clinical practice

A shared vision of care is an aspirational concept which is difficult to articulate but with attentiveness, sustained authentic engagement and being driven by values, it should evolve amongst the core participants of a ‘Community of Clinical Practice’.
Validating an electronic health literacy scale in an older hispanic population
Authors: Aponte Judith , Nokes Kathleen M.
Published: February 2017

Aim

To examine the validity of the Spanish version of an instrument used to measure electronic health literacy (eHEALS) with an older Hispanic population from a number of Spanish‐language countries living in New York City in the United States (US).

Background

Although the Internet is available globally, complex skills are needed to use this source of valuable health‐related information effectively. Electronic health literacy is a multifactorial concept that includes health literacy but also requires technology skills.

Design

Cross‐sectional.

Method

Recruitment occurred at a Senior Organization located in a largely Hispanic neighbourhood in New York City (N = 100). Participants completed eHEALS and selected items from the Health Information National Trends Survey (HINTS) which assesses how adults use different communication channels, including the Internet, to obtain vital health information. Data from the US HINTS sample (N = 162) were matched to the Senior Organization sample on age range and Hispanic ethnicity. The average Senior Organization participant was 68 years old, female, born in one of six different Spanish‐language countries, and completed high school while the average HINTS participant was 67 years old, female and had high school or less education.

Results

Although there was no relationship with the two HINTS subscales and electronic health literacy, there were significant relationships between electronic health literacy and health status and confidence in self‐care.

Conclusions

Inadequate electronic health literacy is a barrier to positive health outcomes. The Spanish version of eHEALS could be used as a screening instrument to identify gaps and tailored interventions could be developed to increase consumer confidence in using the Internet for reliable health‐related information.

Relevance to clinical practice

Knowledge in self‐management is related to positive health outcomes; all persons irrespective of their electronic health literacy should be able to use all sources of health information to enhance their self‐care.
A PET‐Guided Framework Supports a Multiple Arterial Input Functions Approach in DSC‐MRI in Acute Stroke
Authors: Livne Michelle , Madai Vince I. , Brunecker Peter , Zaro‐Weber Olivier , Moeller‐Hartmann Walter , Heiss Wolf‐Dieter , Mouridsen Kim , Sobesky Jan
Published: February 2017

BACKGROUND AND PURPOSE

In acute stroke, arterial‐input‐function (AIF) determination is essential for obtaining perfusion estimates with dynamic susceptibility‐weighted contrast‐enhanced magnetic resonance imaging (DSC‐MRI). Standard DSC‐MRI postprocessing applies single AIF selection, ie, global AIF. Physiological considerations, however, suggest that a multiple AIFs selection method would improve perfusion estimates to detect penumbral flow. In this study, we developed a framework based on comparable DSC‐MRI and positron emission tomography (PET) images to compare the two AIF selection approaches and assess their performance in penumbral flow detection in acute stroke.

METHODS

In a retrospective analysis of 17 sub(acute) stroke patients with consecutive MRI and PET scans, voxel‐wise optimized AIFs were calculated based on the kinetic model as derived from both imaging modalities. Perfusion maps were calculated based on the optimized‐AIF using two methodologies: (1) Global AIF and (2) multiple AIFs as identified by cluster analysis. Performance of penumbral‐flow detection was tested by receiver–operating characteristics (ROC) curve analysis, ie, the area under the curve (AUC).

RESULTS

Large variation of optimized AIFs across brain voxels demonstrated that there is no optimal single AIF. Subsequently, the multiple‐AIF method (AUC range over all maps: .82‐.90) outperformed the global AIF methodology (AUC .72‐.85) significantly.

CONCLUSIONS

We provide PET imaging‐based evidence that a multiple AIF methodology is beneficial for penumbral flow detection in comparison with the standard global AIF methodology in acute stroke.
Immune system stimulation by the gut symbiont Frischella perrara in the honey bee (Apis mellifera)
Authors: Emery Olivier , Schmidt Konstantin , Engel Philipp
Published: February 2017

Gut bacteria engage in various symbiotic interactions with their host and impact gut immunity and homeostasis in different ways. In honey bees, the gut microbiota is composed of a relatively simple, but highly specialized bacterial community. One of its members, the gammaproteobacterium Frischella perrara induces the so‐called scab phenotype, a dark‐coloured band that develops on the epithelial surface of the pylorus. To understand the underlying host response, we analysed transcriptome changes in the pylorus in response to bacterial colonization. We find that, in contrast to the gut bacterium Snodgrassella alvi, F. perrara causes strong activation of the host immune system. Besides pattern recognition receptors, antimicrobial peptides and transporter genes, the melanization cascade was upregulated by F. perrara, suggesting that the scab phenotype corresponds to a melanization response of the host. In addition, transcriptome analysis of hive bees with and without the scab phenotype showed that F. perrara also stimulates the immune system under in‐hive conditions in the presence of other gut bacterial species. Collectively, our study demonstrates that the presence of F. perrara influences gut immunity and homeostasis in the pylorus. This may have implications for bee health, because F. perrara prevalence differs between colonies and increased abundance of this bacterium has been shown to correlate with dietary alteration and impaired host development. Our transcriptome analysis sets the groundwork for investigating the interplay of bee gut symbionts with the host immune system.
Adaptation of the pathogen, Pseudomonas syringae, during experimental evolution on a native vs. alternative host plant
Authors: Meaden Sean , Koskella Britt
Published: February 2017

The specialization and distribution of pathogens among species has substantial impact on disease spread, especially when reservoir hosts can maintain high pathogen densities or select for increased pathogen virulence. Theory predicts that optimal within‐host growth rate will vary among host genotypes/species and therefore that pathogens infecting multiple hosts should experience different selection pressures depending on the host environment in which they are found. This should be true for pathogens with broad host ranges, but also those experiencing opportunistic infections on novel hosts or that spill over among host populations. There is very little empirical data, however, regarding how adaptation to one host might directly influence infectivity and growth on another. We took an experimental evolution approach to examine short‐term adaptation of the plant pathogen, Pseudomonas syringae pathovar tomato, to its native tomato host compared with an alternative host, Arabidopsis, in either the presence or absence of bacteriophages. After four serial passages (20 days of selection in planta), we measured bacterial growth of selected lines in leaves of either the focal or alternative host. We found that passage through Arabidopsis led to greater within‐host bacterial densities in both hosts than did passage through tomato. Whole genome resequencing of evolved isolates identified numerous single nucleotide polymorphisms based on our novel draft assembly for strain PT23. However, there was no clear pattern of clustering among plant selection lines at the genetic level despite the phenotypic differences observed. Together, the results emphasize that previous host associations can influence the within‐host growth rate of pathogens.
Phylogenetic relatedness explains highly interconnected and nested symbiotic networks of woody plants and arbuscular mycorrhizal fungi in a Chinese subtropical forest
Authors: Chen Liang , Zheng Yong , Gao Cheng , Mi Xiang‐Cheng , Ma Ke‐Ping , Wubet Tesfaye , Guo Liang‐Dong
Published: February 2017

Elucidating symbiotic relationships between arbuscular mycorrhizal fungi (AMF) and plants contributes to a better understanding of their reciprocally dependent coexistence and community assembly. However, the main drivers of plant and AMF community assembly remain unclear. In this study, we examined AMF communities from 166 root samples of 17 woody plant species from 10 quadrats in a Chinese subtropical forest using 454 pyrosequencing of 18S rRNA gene to describe symbiotic AMF–plant association. Our results show the woody plant–AMF networks to be highly interconnected and nested, but in antimodular and antispecialized manners. The nonrandom pattern in the woody plant–AMF network was explained by plant and AMF phylogenies, with a tendency for a stronger phylogenetic signal by plant than AMF phylogeny. This study suggests that the phylogenetic niche conservatism in woody plants and their AMF symbionts could contribute to interdependent AMF and plant community assembly in this subtropical forest ecosystem.
Optimal dose of ramosetron in female patients with irritable bowel syndrome with diarrhea: A randomized, placebo‐controlled phase II study
Authors: Fukudo S. , Matsueda K. , Haruma K. , Ida M. , Hayase H. , Akiho H. , Nakashima Y. , Hongo M.
Published: February 2017

Background

Previous studies showed that 5 μg of ramosetron, a serotonin (5‐hydroxytryptamine: 5‐HT)‐3 receptor antagonist, is only effective in male patients with irritable bowel syndrome (IBS) with diarrhea (IBS‐D). We hypothesized that either dose 1.25, 2.5, or 5 μg of ramosetron would be effective in female patients with IBS‐D.

Methods

This randomized, double‐blind, placebo‐controlled, phase II dose‐finding exploratory trial included 409 female outpatients with IBS‐D treated in Japan. They were administered oral placebo (n=102), or 1.25 μg (n=104), 2.5 μg (n=104), or 5 μg (n=99) of ramosetron once daily for 12 weeks after a 1‐week baseline period. The primary endpoint was monthly responder rates of global improvement of IBS symptoms in the first month. Secondary endpoints included global improvement in the other months, abdominal pain/discomfort, weekly mean changes in the Bristol Stool Form Scale (BSFS), and IBS‐QOL.

Key Results

Middle dose (2.5 μg) of ramosetron significantly improved abdominal pain/discomfort at second month (62.5%, P=.002), third month (60.6%, P=.005), and the last evaluation point (63.5%, P=.002) and weekly BSFS (P<.05) except at Week 8, 11, and 12 than placebo. IBS‐QOL did not change. Ramosetron induced more constipation than placebo.

Conclusions & Inferences

The trial suggested that 2.5 μg of ramosetron is the most effective and least harmful option for treating female patients with IBS‐D (Clinicaltrials.gov ID: NCT01274000).
Is colchicine more effective to prevent periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis episodes in Mediterranean fever gene variants?
Authors: Gunes Muhammed , Cekic Sukru , Kilic Sara Sebnem
Published: February 2017

Background

Periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) syndrome is the most frequent repetitive fever syndrome in childhood. It is characterized by fever episodes lasting for approximately 3–6 days, once every 3–8 weeks.

Methods

Clinical and laboratory data for PFAPA syndrome patients between January 2010 and December 2014 followed up at a tertiary pediatric care hospital were reviewed.

Results

Four hundred children (256 male, 144 female; mean age at diagnosis, 4.2 ± 2.2 years), were enrolled in the study. During the episodes, mean leukocyte number was high (12 725/mm3) with predominant neutrophils. The mean number of monocytes was 1256/mm3, and 90.2% had monocytosis. Serum amyloid A and C‐reactive protein were high in 84.6% and in 77.8% of the patients, respectively. Mediterranean fever (MEFV) gene heterozygous mutation was identified in 57 of the 231 patients (24.7%) in whom genetic analysis had been performed. The most frequent mutation was heterozygous M694V (10%, n = 23). Extension of between‐episode interval following prophylaxis was noted in 85% of those on regular colchicine treatment (n = 303). In the colchicine group, between‐episode interval was prolonged from 18.8 ± 7.9 days (before colchicine treatment) to 49.5 ± 17.6 days on prophylactic colchicine therapy; also, prophylactic treatment was more effective in reducing episode frequency in patients with MEFV gene variant (n = 54, 96%) than in those without (n = 122, 80%; P = 0.003).

Conclusions

This study has involved the largest number of PFAPA syndrome patients in the literature. It is particularly important to assess and to demonstrate the high rate of response to colchicine prophylaxis in PFAPA syndrome patients, especially those with MEFV variant. On blood screening, neutrophilia associated with monocytosis and low procalcitonin could contribute to diagnosis.
Nonparametric Two‐Sample Tests of the Marginal Mark Distribution with Censored Marks
Authors: Johnson Brent A.
Published: February 2017

Occasionally, investigators collect auxiliary marks at the time of failure in a clinical study. Because the failure event may be censored at the end of the follow‐up period, these marked endpoints are subject to induced censoring. We propose two new families of two‐sample tests for the null hypothesis of no difference in mark‐scale distribution that allows for arbitrary associations between mark and time. One family of proposed tests is a nonparametric extension of an existing semi‐parametric linear test of the same null hypothesis while a second family of tests is based on novel marked rank processes. Simulation studies indicate that the proposed tests have the desired size and possess adequate statistical power to reject the null hypothesis under a simple change of location in the marginal mark distribution. When the marginal mark distribution has heavy tails, the proposed rank‐based tests can be nearly twice as powerful as linear tests.
Lipoprotein lipase activity does not predict very low‐density lipoprotein‐triglyceride fatty acid oxidation during exercise
Authors: Søndergaard E. , Andersen I. R. , Sørensen L. P. , Gormsen L. C. , Nielsen S.
Published: February 2017

Exercise lowers plasma triglyceride levels, but the physiological mechanisms remain not fully elucidated. Lipoprotein lipase (LPL) is a key enzyme in facilitating fatty acid uptake from lipoproteins. As exercise increases the efficiency of very low‐density lipoprotein‐triglyceride (VLDL‐TG) oxidation, we hypothesized that muscle LPL activity would be a rate‐limiting step and predict VLDL‐TG Fatty acids oxidation during exercise. Sixteen healthy, lean subjects (eight men and eight women) were examined before and during an acute exercise bout (90 minutes at 50% of VO2‐max). Heparin‐releasable LPL activity was measured in muscle and adipose tissue biopsies. Breath 14CO2 was measured after a primed‐constant infusion of ex vivo labeled [14C]‐triolein VLDL‐TG. Fractional VLDL‐TG storage was measured in adipose tissue biopsies. Exercise did not affect muscle LPL activity (P=.30). No association was observed between muscle LPL activity and VLDL‐TG oxidation, neither in the basal state (P=.17) nor during exercise (P=.83). Exercise did not affect upper body or lower body adipose tissue LPL activity (both P=.92). The basal adipose tissue fractional VLDL‐TG storage (abdominal.13%±9%; femoral 17%±10% (P=.18)) was not associated with upper body (P=.56) or lower body (P=.44) subcutaneous adipose tissue LPL activity. Muscle LPL activity does not predict VLDL‐TG oxidation during rest or exercise. In addition, adipose tissue LPL activity was not associated with VLDL‐TG storage during rest. This suggests that LPL activity is present in excess of what is required to facilitate lipid uptake for oxidation during both rest and exercise.
The Interplay between Equity and Gender Ideology in Perceived Housework Fairness: Evidence from an Experimental Vignette Design
Authors: Carriero Renzo , Todesco Lorenzo
Published: February 2017

Previous survey studies on the perceived fairness of the division of housework have suffered from limitations resulting from the use of observational data, namely reverse causation, unobserved heterogeneity, and the difficulty of estimating more than one causal effect at once. This article overcomes these limitations by using an innovative method in this research field: a survey‐based vignette design combining the benefits of experiments with a higher capability of generalization. From our findings based on Italian primary data, we argue that equity and gender ideology theories explain different elements of the fairness evaluation process and are not mutually exclusive. Consistent with equity theory, under certain conditions it is considered fair to exchange paid and unpaid time. However, unlike equity theory, the economic value of time is not an issue. Moreover, a request to renegotiate housework is more legitimate if it redresses a prior inequity and, for women, irrespective of the asker's gender. Gender ideology affects partners' equity considerations, weighting their contribution to paid and unpaid work differently.
Using Foucault's theory of disciplinary power to critically examine the construction of gender in secondary schools
Authors: Graham Katie , Treharne Gareth J. , Nairn Karen
Published: February 2017

Schools are typically thought of as important places for young people to learn specific academic skills. This review synthesises research from “western” English‐speaking countries to argue that young people learn more than just academic skills at school. Specifically, the review explores how aspects of classroom teaching and culture contribute to how young people understand gender. Drawing on Foucault's theory of disciplinary power, practices within schools are deconstructed to show how they create certain gendered ways of being. The discourses of gender within schools are critiqued by highlighting how they limit diverse expressions of gender. Section 3 of the review draws on literature to highlight how dominant discourses and the practices that create them can be resisted creating the opportunity for other discourses of gender.
A novel HLA‐E allele, HLA‐E*01:01:01:06, identified in a Chinese Leukemia patient
Authors: Xu Y.‐P. , Wang S.‐X. , Hong W.‐X.
Published: February 2017

A novel HLA‐E allele, HLA‐E*01:01:01:06, was identified in a Chinese leukemia patient.
Risk factors of human herpesvirus 6 encephalitis/myelitis after allogeneic hematopoietic stem cell transplantation
Authors: Miyashita Naohiro , Endo Tomoyuki , Onozawa Masahiro , Hashimoto Daigo , Kondo Takeshi , Fujimoto Katsuya , Kahata Kaoru , Sugita Junichi , Goto Hideki , Matsukawa Toshihiro , Hashino Satoshi , Teshima Takanori
Published: February 2017

Background

Human herpesvirus 6 (HHV‐6) encephalitis/myelitis is now a well‐known complication after allogeneic stem cell transplantation (allo‐HSCT), particularly after cord blood transplantation (CBT). In this study, we evaluated the risk factors of HHV‐6 encephalitis/myelitis.

Methods

We evaluated 253 patients who received allo‐HSCT from 2007 to 2015 at our institute. HHV‐6 encephalitis/myelitis was defined as HHV‐6 DNA detection in the cerebrospinal fluid or peripheral blood by polymerase chain reaction in the presence of typical manifestations without other concurrent condition that led to the manifestations.

Results

HHV‐6 encephalitis/myelitis occurred in 11 patients (4.5%) (9 encephalitis, 3.7%; 2 myelitis, 0.8%). Multivariate analysis showed that CBT, mycophenolate mofetil (MMF) for graft‐versus‐host disease prophylaxis, history of allogeneic hematopoietic stem cell transplantation (allo‐HSCT), and engraftment syndrome (ES) were significantly associated with incidence of HHV‐6 encephalitis/myelitis (P=.025, P=.017, P=.017, and P=.014, respectively).

Conclusion

Although it has been shown that CBT, ES, and history of allo‐HSCT are risk factors for HHV‐6 encephalitis/myelitis, our study demonstrated MMF is also a risk factor for the disease.
Trends in US minority red blood cell unit donations
Authors: Yazer Mark H. , Delaney Meghan , Germain Marc , Karafin Matthew S. , Sayers Merlyn , Vassallo Ralph , Ziman Alyssa , Shaz Beth ,   on behalf of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative
Published: February 2017

BACKGROUND

To provide the appropriately diverse blood supply necessary to support alloimmunized and chronically transfused patients, minority donation recruitment programs have been implemented. This study investigated temporal changes in minority red blood cell (RBC) donation patterns in the United States.

STUDY DESIGN AND METHODS

Data on donor race and ethnicity from 2006 through 2015, including the number of unique donors, collections, RBCs successfully donated, and average annual number of RBC donations per donor (donor fraction), were collected from eight US blood collectors. Minority donors were stratified into the following groups: Asian, black or African American, Hispanic or Latino, Native Indian or Alaska Native, Native Hawaiian or other Pacific Islander, white, multiracial/other, and no answer/not sure.

RESULTS

Over the 10‐year period, white donors annually constituted the majority of unique donors (range, 70.7%‐73.9%), had the greatest proportion of collections (range, 76.1%‐79.8%), and donated the greatest proportion of RBC units (range, 76.3%‐80.2%). These donors also had the highest annual donor fraction (range, 1.82‐1.91 units per donor). Black or African American donors annually constituted between 4.9 and 5.2% of all donors during the study period and donated between 4.0 and 4.3% of all RBC units. Linear regression analysis revealed decreasing numbers of donors, collections, and donated RBC units from white donors over time.

CONCLUSION

Although the US population has diversified, and minority recruitment programs have been implemented, white donors constitute the majority of RBC donors and donations. Focused and effective efforts are needed to increase the proportion of minority donors.
The influence of patellar tendon and muscle–tendon unit stiffness on quadriceps explosive strength in man
Authors: Massey Garry J. , Balshaw Thomas G. , Maden‐Wilkinson Thomas M. , Tillin Neale A. , Folland Jonathan P.
Published: February 2017

New Findings

What is the central question of this study?

Do tendon and/or muscle–tendon unit stiffness influence rate of torque development?

What is the main finding and its importance?

In our experimental conditions, some measures of relative (to maximal voluntary torque and tissue length) muscle–tendon unit stiffness had small correlations with voluntary/evoked rate of torque development over matching torque increments. However, absolute and relative tendon stiffness were unrelated to voluntary and evoked rate of torque development. Therefore, the muscle aponeurosis but not free tendon influences the relative rate of torque development. Factors other than tissue stiffness more strongly determine the absolute rate of torque development.

The influence of musculotendinous tissue stiffness on contractile rate of torque development (RTD) remains opaque. In this study, we examined the relationships between both patellar tendon (PT) and vastus lateralis muscle–tendon unit (MTU) stiffness and the voluntary and evoked knee‐extension RTD. Fifty‐two healthy untrained men completed duplicate laboratory sessions. Absolute and relative RTD were measured at 50 N m or 25% maximal voluntary torque (MVT) increments from onset and sequentially during explosive voluntary and evoked octet isometric contractions (supramaximal stimulation; eight pulses at 300 Hz). Isometric MVT was also assessed. Patellar tendon and MTU stiffness were derived from simultaneous force and ultrasound recordings of the PT and vastus lateralis aponeurosis during constant RTD ramp contractions. Absolute and relative (to MVT and resting tissue length) stiffness (k) was measured over identical torque increments as RTD. Pearson's correlations tested relationships between stiffness and RTD measurements over matching absolute/relative torque increments. Absolute and relative PT k were unrelated to equivalent voluntary/evoked (r = 0.020–0.255, P = 0.069–0.891). Absolute MTU k was unrelated to voluntary or evoked RTD (r ≤ 0.191, P ≥ 0.184), but some measures of relative MTU k were related to relative voluntary/evoked RTD (e.g. RTD for 25–50% MVT, r = 0.374/0.353, P = 0.007/0.014). In conclusion, relative MTU k explained a small proportion of the variance in relative voluntary and evoked RTD (both ≤19%), despite no association of absolute MTU k or absolute/relative PT k with equivalent RTD measures. Therefore, the muscle‐aponeurosis component but not free tendon was associated with relative RTD, although it seems that an overriding influence of MVT negated any relationship of absolute MTU k and absolute RTD.
Linking myofilaments to sudden cardiac death: recent advances
Authors: Huke Sabine
Published: February 2017

The major goal of this focused review is to highlight some of the recent advances and remaining open questions about how a mutation in a myofilament protein leads to an increased risk for sudden cardiac death (SCD). The link between myofilaments and SCD has been known for over 25 years, but identifying mutation carriers at risk for SCD is still a challenge and currently the only effective prevention is implantation of a defibrillator (ICD). In addition to recognized risk factors, other contributing factors need to be considered and assessed, e.g. ‘microvascular dysfunction’, to calibrate individual risk more accurately. Similarly, improving our understanding about the underlying mechanisms of SCD in patients with sarcomeric mutations will also allow us to design new and less invasive treatment options that will minimize risk and hopefully make implantation of an ICD unnecessary.

image
Enhancement of Interfacial Thermal Conductance of SiC by Overlapped Carbon Nanotubes and Intertube Atoms
Authors: Deng Chengcheng , Yu Xiaoxiang , Huang Xiaoming , Yang Nuo
Published: February 2017

A new way was proposed to enhance the interfacial thermal conductance (ITC) of silicon carbide (SiC) composite through the overlapped carbon nanotubes (CNTs) and intertube atoms. By nonequilibrium molecular dynamics (NEMD) simulations, the dependence of ITC on both the number of intertube atoms and the temperature was studied. It is indicated that the ITC can be significantly enhanced by adding intertube atoms and finally becomes saturated with the increase of the number of intertube atoms. And the mechanism is discussed by analyzing the probability distributions of atomic forces and vibrational density of states (VDOS). This work may provide some guidance on enhancing the ITC of CNT-based composites.
Characterization of a cylindrical ring-cusp ion source with electrically isolated magnet rings
Authors: Arthur Neil A. , Foster John E.
Published: February 2017

A method is explored to increase the current available for beam extraction by way of increasing bulk plasma ion directed drift velocity in the direction of the ion optics. The enhanced ion drift velocity is achieved by spatially modifying the plasma potential through biasing the individual magnet rings in a four ring, magnetic cusp ion thruster. Actual plasma potential changes were tracked using an emissive probe. The modification of the ion drift velocity is observed using Mach probes. The accompanying increase in ion current at the grid was also observed. A retarding potential analyzer located just downstream of the extraction optics was used to observe the shift in energy of exiting ions. Plasma potential shifts up to 5 V were observed. Simulated beam current rose 15% and 20% for xenon and argon, respectively.
Determination of the Sun's and the Moon's sizes and distances: Revisiting Aristarchus' method
Authors: Momeni F. , Papei H. , Jamshidzadeh R. , Bereliani S. , Miri A. , Aghababaei A. , Nikjoo N. , Mehdizadehi E. , Akbari Gurabi M. , Ghasabi Kondelaji N.
Published: February 2017

We have investigated the practicability of Aristarchus' method of determining the Sun's and the Moon's sizes and distances from Earth using a simple 8-in. telescope and a digital camera. Combining our astrometric observations made on October 20, 2012 with data from the lunar eclipse of June 15, 2011, and adopting a proper statistical approach, we obtain the two distances with errors of a few percent for the Moon and about 10% for the Sun. We also explain quantitatively why Aristarchus and his contemporaries, though able to measure the Moon's size and distance acceptably, could not be successful in determining the Sun's size and distance. Our experiment can be carried out in small semi-professional or amateur observatories and can be performed in an astronomy lab class.
Project-based physics labs using low-cost open-source hardware
Authors: Bouquet F. , Bobroff J. , Fuchs-Gallezot M. , Maurines L.
Published: February 2017

We describe a project-based physics lab, which we proposed to third-year university students. These labs are based on new open-source low-cost equipment (Arduino microcontrollers and compatible sensors). Students are given complete autonomy: they develop their own experimental setup and study the physics topic of their choice. The goal of these projects is to let students to discover the reality of experimental physics. Technical specifications of the acquisition material and case studies are presented for practical implementation in other universities.
Collaborative exams: Cheating? Or learning?
Authors: Jang Hyewon , Lasry Nathaniel , Miller Kelly , Mazur Eric
Published: February 2017

Virtually all human activity involves collaboration, and yet, collaboration during an examination is typically considered cheating. Collaborative assessments have not been widely adopted because of the perceived lack of individual accountability and the notion that collaboration during assessments simply causes propagation of correct answers. Hence, collaboration could help weaker students without providing much benefit to stronger students. In this paper, we examine student performance in open-ended, two-stage collaborative assessments comprised of an individually accountable round followed by an automatically scored, collaborative round. We show that collaboration entails more than just propagation of correct answers. We find greater rates of correct answers after collaboration for all students, including the strongest members of a team. We also find that half of teams that begin without a correct answer to propagate still obtain the correct answer in the collaborative round. Our findings, combined with the convenience of automatic feedback and grading of open-ended questions, provide a strong argument for adopting collaborative assessments as an integral part of education.
Consonant categorization exhibits a graded influence of surrounding spectral context
Authors: Stilp Christian E. , Assgari Ashley A.
Published: February 2017

When spectral properties differ across successive sounds, this difference is perceptually magnified, resulting in spectral contrast effects (SCEs). Recently, Stilp, Anderson, and Winn [(2015) J. Acoust. Soc. Am. 137(6), 3466–3476] revealed that SCEs are graded: more prominent spectral peaks in preceding sounds produced larger SCEs (i.e., category boundary shifts) in categorization of subsequent vowels. Here, a similar relationship between spectral context and SCEs was replicated in categorization of voiced stop consonants. By generalizing this relationship across consonants and vowels, different spectral cues, and different frequency regions, acute and graded sensitivity to spectral context appears to be pervasive in speech perception.
Hawkmoths use nectar sugar to reduce oxidative damage from flight
Authors: Levin E. , Lopez-Martinez G. , Fane B. , Davidowitz G.
Published: February 2017

Sugar rush

Flying requires high levels of energy production, which causes muscular oxidative damage. Food-derived antioxidants can protect against such damage; however, nectar is devoid of these compounds. Levin
et al.
found that nectar-feeding hawkmoths fed high concentrations of sugar had lower levels of damage than unfed moths. Sugar-fed moths generated antioxidant compounds by shunting glucose through a pentose phosphate pathway. This mechanism may have allowed for the evolution of energy-intensive flying nectarivores.

Science
, this issue p.
733
Lipid transport by TMEM24 at ER–plasma membrane contacts regulates pulsatile insulin secretion
Authors: Lees Joshua A. , Messa Mirko , Sun Elizabeth Wen , Wheeler Heather , Torta Federico , Wenk Markus R. , De Camilli Pietro , Reinisch Karin M.
Published: February 2017

Understanding insulin release

Insulin release takes place in two phases: a first rapid burst followed by a series of small exocytic bursts that coincide with pulsatile spikes in cytosolic Ca
2+
levels. The second phase is impaired in patients with type II diabetes, underscoring the importance of understanding its molecular basis. Lees
et al.
report a mechanism through which TMEM24, a lipid transport protein that concentrates at endoplasmic reticulum–plasma membrane contact sites, regulates the pulsatility of cytosolic Ca
2+
and phosphoinositide signaling. This process in turn regulates pulsatile insulin secretion during the slow insulin release phase.

Science
, this issue p.
eaah6171
Localized aliphatic organic material on the surface of Ceres
Authors: De Sanctis M. C. , Ammannito E. , McSween H. Y. , Raponi A. , Marchi S. , Capaccioni F. , Capria M. T. , Carrozzo F. G. , Ciarniello M. , Fonte S. , Formisano M. , Frigeri A. , Giardino M. , Longobardo A. , Magni G. , McFadden L. A. , Palomba E. , Pieters C. M. , Tosi F. , Zambon F. , Raymond C. A. , Russell C. T.
Published: February 2017

Organic compounds detected on Ceres

Water and organic molecules were delivered to the early Earth by the impacts of comets and asteroids. De Sanctis
et al.
examined infrared spectra taken by the Dawn spacecraft as it orbited Ceres, the largest object in the asteroid belt (see the Perspective by Küppers). In some small patches on the surface, they detected absorption bands characteristic of aliphatic organic compounds. The authors ruled out an external origin, such as an impact, suggesting that the material must have formed on Ceres. Together with other compounds detected previously, this supports the existence of a complex prebiotic chemistry at some point in Ceres' history.

Science
, this issue p.
719
; see also p.
692
Vitamin B
3
modulates mitochondrial vulnerability and prevents glaucoma in aged mice
Authors: Williams Pete A. , Harder Jeffrey M. , Foxworth Nicole E. , Cochran Kelly E. , Philip Vivek M. , Porciatti Vittorio , Smithies Oliver , John Simon W. M.
Published: February 2017

Vitamin B
3
protects mice from glaucoma

Glaucoma is the most common cause of age-related blindness in the United States. There is currently no cure, and once vision is lost, the condition is irreversible. Williams
et al.
now report that vitamin B
3
(also known as niacin) prevents eye degeneration in glaucoma-prone mice (see the Perspective by Crowston and Trounce). Supplementing the diets of young mice with vitamin B
3
averted early signs of glaucoma. Vitamin B
3
also halted further glaucoma development in aged mice that already showed signs of the disease. Thus, healthy intake of vitamin B
3
may protect eyesight.

Science
, this issue p.
756
; see also p.
688
Seagrass ecosystems reduce exposure to bacterial pathogens of humans, fishes, and invertebrates
Authors: Lamb Joleah B. , van de Water Jeroen A. J. M. , Bourne David G. , Altier Craig , Hein Margaux Y. , Fiorenza Evan A. , Abu Nur , Jompa Jamaluddin , Harvell C. Drew
Published: February 2017

Missing meadows fail to mop up microbes

Seagrass meadows, a prominent feature of most healthy coastal ecosystems, are often also associated with shallow coral reefs. Many plants have bioremediation qualities, and seagrasses, of which there are 60 or so species, produce natural biocides. Lamb
et al.
found that the seagrass meadows of inhabited atolls near Sulawesi, Indonesia, ameliorated seawater pollution from human-origination bacteria. This effect extended to potential pathogens of marine invertebrates and fish: Reefs fringing the seagrass meadows showed significantly less impact from coral and fish disease.

Science
, this issue p.
731
Catalytic intermolecular hydroaminations of unactivated olefins with secondary alkyl amines
Authors: Musacchio Andrew J. , Lainhart Brendan C. , Zhang Xin , Naguib Saeed G. , Sherwood Trevor C. , Knowles Robert R.
Published: February 2017

Hydroamination gets a light push uphill

Hydroamination of olefins is a broadly useful method for making carbon-nitrogen bonds. However, when both the amine and the olefin have multiple alkyl substituents, the reaction can become energetically unfavorable. Musacchio
et al.
used the energy in blue light to surmount this obstacle (see the Perspective by Buchanan and Hull). A photo-excited iridium complex oxidized the amine, which in turn bonded efficiently to the olefin, after which a thiophenol cocatalyst shuttled the electron back. The reaction could operate across a wide range of amine and olefin partners.

Science
, this issue p.
727
; see also p.
690