Magnetic Braking in Differentially Rotating, Relativistic Stars

We study the magnetic braking and viscous damping of differential rotation in incompressible, uniform density stars in general relativity. Differentially rotating stars can support significantly more mass in equilibrium than nonrotating or uniformly rotating stars. The remnant of a binary neutron star merger or supernova core collapse may produce such a "hypermassive" neutron star. Although a hypermassive neutron star may be stable on a dynamical timescale, magnetic braking and viscous damping of differential rotation will ultimately alter the equilibrium structure, possibly leading to delayed catastrophic collapse. Here we consider the slow-rotation, weak-magnetic field limit in which E_rot << E_mag << W, where E_rot is the rotational kinetic energy, E_mag is the magnetic energy, and W is the gravitational binding energy of the star. We assume the system to be axisymmetric and solve the MHD equations in both Newtonian gravitation and general relativity. Toroidal magnetic fields are generated whenever the angular velocity varies along the initial poloidal field lines. We find that the toroidal fields and angular velocities oscillate independently along each poloidal field line, which enables us to transform the original 2+1 equations into 1+1 form and solve them along each field line independently. The incoherent oscillations on different field lines stir up turbulent-like motion in tens of Alfven timescales ("phase mixing"). In the presence of viscosity, the stars eventually are driven to uniform rotation, with the energy contained in the initial differential rotation going into heat. Our evolution calculations serve as qualitative guides and benchmarks for future, more realistic MHD simulations in full 3+1 general relativity.Comment: 26 pages, 27 graphs, 1 table, accepted for publication by Phys. Rev.

Identification of independent association signals and putative functional variants for breast cancer risk through fine-scale mapping of the 12p11 locus.

BACKGROUND: Multiple recent genome-wide association studies (GWAS) have identified a single nucleotide polymorphism (SNP), rs10771399, at 12p11 that is associated with breast cancer risk. METHOD: We performed a fine-scale mapping study of a 700 kb region including 441 genotyped and more than 1300 imputed genetic variants in 48,155 cases and 43,612 controls of European descent, 6269 cases and 6624 controls of East Asian descent and 1116 cases and 932 controls of African descent in the Breast Cancer Association Consortium (BCAC; http://bcac.ccge.medschl.cam.ac.uk/ ), and in 15,252 BRCA1 mutation carriers in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Stepwise regression analyses were performed to identify independent association signals. Data from the Encyclopedia of DNA Elements project (ENCODE) and the Cancer Genome Atlas (TCGA) were used for functional annotation. RESULTS: Analysis of data from European descendants found evidence for four independent association signals at 12p11, represented by rs7297051 (odds ratio (OR) = 1.09, 95 % confidence interval (CI) = 1.06-1.12; P = 3 × 10(-9)), rs805510 (OR = 1.08, 95 % CI = 1.04-1.12, P = 2 × 10(-5)), and rs1871152 (OR = 1.04, 95 % CI = 1.02-1.06; P = 2 × 10(-4)) identified in the general populations, and rs113824616 (P = 7 × 10(-5)) identified in the meta-analysis of BCAC ER-negative cases and BRCA1 mutation carriers. SNPs rs7297051, rs805510 and rs113824616 were also associated with breast cancer risk at P < 0.05 in East Asians, but none of the associations were statistically significant in African descendants. Multiple candidate functional variants are located in putative enhancer sequences. Chromatin interaction data suggested that PTHLH was the likely target gene of these enhancers. Of the six variants with the strongest evidence of potential functionality, rs11049453 was statistically significantly associated with the expression of PTHLH and its nearby gene CCDC91 at P < 0.05. CONCLUSION: This study identified four independent association signals at 12p11 and revealed potentially functional variants, providing additional insights into the underlying biological mechanism(s) for the association observed between variants at 12p11 and breast cancer risk.UK funding includes Cancer Research UK and NIH.This is the final version of the article. It first appeared from BioMed Central via http://dx.doi.org/10.1186/s13058-016-0718-

Coping Strategies of Children Exposed to Domestic Violence

研究目的：當家庭裡出現婚姻暴力時，受害者可能不僅止於受虐配偶，對於同住家中的子女而言，亦可能造成嚴重的身心傷害。然而，國內對於婚姻暴力目睹兒童的服務仍受限於心有餘而力不足的現況，對於目睹兒童的了解與探討亦在起步的階段。因此，本文旨在深入了解子女目睹婚姻暴力當下的情感與行為因應方式，以期助人工作者對婚暴子女的經歷與感受有更深層的同理，進而提供目睹兒童最適切的處遇服務。研究方法：本研究之母群體為南投縣家暴中心所受理之家庭暴力通報事件之案主或案家，以普查的方式，針對208個家庭，以半結構式的訪談大綱進行面訪。其中同意接受深入訪談的成人有200位（98.6%是女性）；同意接受深入訪談的子女有192位。研究結果：本研究發現，子女在目睹婚暴衝突時的情感反應包括：恐懼、憤怒、擔憂、焦慮、被忽視、矛盾、與絕望想死的意念等。本研究亦發現子女會學習模仿父母的暴力行為，攻擊手足甚至是父母。在婚姻暴力發生的當下，子女的行為反應包括：害怕躲避、不知所措、挺身介入、尋求援助及無動於衷。值得注意的是，子女的行為反應會隨著年齡而有所不同。年紀較小的子女會採取躲避的方式，不敢輕舉妄動；等到上了國高中，就比較敢出面制止、保護母親，甚至向加害者（通常是父親）反擊。Purpose: When domestic violence occurs in the family, the negative consequences may not be limited to the married couple. Domestic violence may also have a deep and negative impact on children who are exposed to it. However, the study and service of children exposed to domestic violence is still in the beginning stages in Taiwan. Therefore, this study aims to investigate the children's emotional responses and coping behaviors when witnessing domestic violence. Practitioners can better help and empathize with those children by understanding their experiences and feelings after their exposure to domestic violence. Methods: The research design of this study is cross-sectional. This studyinterviewed both parents and children. Qualitative data was collected from a clinical sample of 200 parents and 192 children who had reported incidents of family violence to the official agencies in Nantau Hsian. Qualitative data were coded, discussed, and analyzed in this paper. Results: 1. Emotional responses of children exposed to domestic violence include: fear, anxiety, worry, anger, feeling ignored, hopeless, and having thought of death. 2. Children's coping strategies include hiding, not knowing what to do, stopping violence, seeking help, and doing nothing. Children's coping strategies varied according to their age. Younger children tend to hide; while older children tend to intervene or fight against the abuser

Preliminary report of associated factors in wound infection after major head and neck neoplasm operations - does the duration of prophylactic antibiotic matter?

The aim of this study was to investigate whether an extended course of prophylactic antibiotic could reduce the wound infection rate in a subtropical country. Fifty-three consecutive cases scheduled to receive major head and neck operations were randomised into one-day or three-day prophylactic antibiotic groups. Thirteen cases (24.5 per cent) developed wound infections after operations. The duration of prophylactic antibiotic was not related to the surgical wound infection. However, pre-operative haemoglobulin less than 10.5 g/dl (odds ratio: 7.24, 95 per cent confidence interval: 1.28-41.0) and reconstruction with a free flap or pectoris major myocutaneous flap during the operation (odds ratio: 11.04, 95 per cent confidence interval: 1.17-104.7) were associated factors significantly influencing post-operative wound infection. Therefore, one day of prophylactic antibiotic was effective in major head and neck procedures but should not be substituted for proper aseptic and meticulous surgical techniques

Activated matrix metalloproteinase and disrupted myocardial collagen matrix in increased sympathetic activity following stimulation of dorsal medulla in the vagotomized feline model

Sympathetic hyperactivation in many kinds of neurocardiogenic injury can result in obvious heart failure. We generated a vagotomized feline model in which sympathetic hyperactivation was induced by electrical stimulation of dorsal medulla (ESDM) of brain stem to investigate the relationship between disruption of extracellular collagen matrix (ECM) and activation of matrix metalloproteinases (MMPs) in myocardium in the sympathetic hyperactivity. Mean blood pressure, heart rate and plasma norepinephrine were all significantly increased from baseline to a peak at 5 min after ESDM. Echocardiographic study showed significant left ventricular dilatation and hypokinesia (ejection fraction: from 87.7 +/- 6.3% to 39.4 +/- 7.8%) from baseline to 180 mm after ESDM. Histopathological finding revealed significant overstretching or spring-like disappearance and disruption of ECM. MMP-2 expression was significantly increased in left ventricular myocardium as compared to sham. These results suggest that ESDM-induced sympathetic hyperactivity causes the expression of MMP-2 that disrupts myocardial ECM, contributing to the development of cardiac dysfunction

The impact of different closure materials on pharyngeal wound healing: an experimental animal study

The formation of pharyngo-cutaneous fistula (PCF) is controversial and various predisposing factors have been proposed. This study aimed to compare different suture materials in the closure of pharyngeal wounds in experimental animals. Fifty-two Sprague-Dawley rats were divided into three groups. Artificial pharyngotomy was performed and was then repaired with Vicryl, polypropylene, and Vicryl plus fibrin glue, respectively. Outcome measurements included gross wound inspection and histological examination. There was a significant difference in the rates of PCF formation between group I and group II (Fisher's exact test, p = 0.046). In addition, minimal inflammatory response was found in the polypropylene group when compared to the other groups. The fibrin glue-treated group had the highest fibroblast activity and collagen deposition. Polypropylene produced minimal tissue reaction, which facilitated the healing process. Therefore, proper selection of suture material can probably reduce the rate of PCF but should not be substituted for proper aseptic and meticulous surgical techniques

Bronchiolitis Obliterans Organizing Pneumonia in Swine Associated with Porcine Circovirus Type 2 Infection

Bronchiolitis obliterans organizing pneumonia (BOOP) is a chronic respiratory disease. Although the pathogenesis of BOOP is still incompletely understood, BOOP is responsive to steroids and has a good prognosis. In our five pigs with chronic postweaning multisystemic wasting syndrome (PMWS), typical BOOP lesions were revealed. All five porcine lungs showed typical intraluminal plugs, and porcine circovirus type 2 (PCV2) was identified. They also exhibited similar pathologic findings such as proliferation of type II pneumocytes and myofibroblasts (MFBs), extracellular collagen matrix (ECM) deposition, and fragmentation of elastic fibers. MFBs migration correlative molecules, for instance, gelatinase A, B and osteopontin, appeared strongly in the progressing marginal area of polypoid intraluminal plugs of fibrotic lesion. These molecules colocalized with the active MFBs. Both gelatinase activity and intercellular level of active MFBs were significantly increased (P < .05). Porcine chronic bronchopneumonia leads to BOOP and it is associated with PCV2 persistent infection. Swine BOOP demonstrates similar cellular constituents with human BOOP. Perhaps their molecular mechanisms of pathogenesis operate in a similar way. Thus we infer that the swine BOOP can be considered as a potential animal model for human BOOP associated with natural viral infection. Moreover, it is more convenient to obtain samples