bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of PAH photodissociation on the formation of small hydrocarbons in the Orion Bar and the horsehead PDRs
Authors: Murga M S , Kirsanova M S , Vasyunin A I , Pavlyuchenkov Ya N 
Published: July 2020

ABSTRACT
We study whether polycyclic aromatic hydrocarbons (PAHs) can be a weighty source of small hydrocarbons in photodissociation regions (PDRs). We modelled the evolution of 20 specific PAH molecules in terms of dehydrogenation and destruction of the carbon skeleton under the physical conditions of two well-studied PDRs, the Orion Bar, and the Horsehead nebula that represent prototypical examples of PDRs irradiated by ‘high’ and ‘low’ ultraviolet radiation field. PAHs are described as microcanonical systems. The acetylene molecule is considered as the main carbonaceous fragment of the PAH dissociation, as it follows from laboratory experiments and theory. We estimated the rates of acetylene production in gas phase chemical reactions and compared them with the rates of the acetylene production through the PAH dissociation. It is found that the latter rates can be higher than the former rates in the Orion Bar at AV &lt; 1 and also at AV &gt; 3.5. In the Horsehead nebula, the chemical reactions provide more acetylene than the PAH dissociation. The produced acetylene participate in the reactions of the formation of small hydrocarbons (C2H, C3H, C3H+, C3H2, C4H). Acetylene production via the PAH destruction may increase the abundances of small hydrocarbons produced in gas phase chemical reactions in the Orion Bar only at AV &gt; 3.5. In the Horsehead nebula, the contribution of PAHs to the abundances of the small hydrocarbons is negligible. We conclude that the PAHs are not a major source of small hydrocarbons in both PDRs except some locations in the Orion Bar.
The stringent upper limit on jet power in the persistent soft-state source 4U 1957+11
Authors: Maccarone Thomas J , Osler Arlo , Miller-Jones James C A , Atri P , Russell David M , Meier David L , McHardy Ian M , Longa-Peña Penelope A 
Published: July 2020

ABSTRACT
We present extremely deep upper limits on the radio emission from 4U 1957+11, an X-ray binary that is generally believed to be a persistently accreting black hole that is almost always in the soft state. We discuss a more comprehensive search for Type I bursts than in past work, revealing a stringent upper limit on the burst rate, bolstering the case for a black hole accretor. The lack of detection of this source at the 1.07 μJy/beam noise level indicates jet suppression that is stronger than expected even in the most extreme thin disc models for radio jet production – the radio power here is 1500–3700 times lower than the extrapolation of the hard state radio/X-ray correlation, with the uncertainties depending primarily on the poorly constrained source distance. We also discuss the location and velocity of the source and show that it must have either formed in the halo or with a strong asymmetric natal kick.
The origin of the black hole offset in M31
Authors: Boldrini Pierre 
Published: July 2020

ABSTRACT
Using state-of-the-art high-resolution fully GPU N-body simulations, we demonstrate for the first time that the infall of a dark matter-rich satellite naturally explains a present black hole offset by subparsecs in M31. Observational data of the tidal features provide stringent constraints on the initial conditions of our simulations. The heating of the central region of M31 by the satellite via dynamical friction entails a significant black hole offset after the first pericentric passage. After having reached its maximum offset, the massive black hole sinks towards the M31 centre due to dynamical friction and it is determined to be offset by subparsecs as derived by observations.
Predicting Postoperative Outcomes in Brain Tumor Patients With a 5-Factor Modified Frailty Index
Authors: Huq Sakibul , Khalafallah Adham M , Jimenez Adrian E , Gami Abhishek , Lam Shravika , Ruiz-Cardozo Miguel A , Oliveira Leonardo A P , Mukherjee Debraj 
Published: July 2020

Abstract

BACKGROUND
Frailty indices may represent useful decision support tools to optimize modifiable drivers of quality and cost in neurosurgical care. However, classic indices are cumbersome to calculate and frequently require unavailable data. Recently, a more lean 5-factor modified frailty index (mFI-5) was introduced, but it has not yet been rigorously applied to brain tumor patients.

OBJECTIVE
To investigate the predictive value of the mFI-5 on length of stay (LOS), complications, and charges in surgical brain tumor patients.

METHODS
We retrospectively reviewed data for brain tumor patients who underwent primary surgery from 2017 to 2018. Bivariate (ANOVA) and multivariate (logistic and linear regression) analyses assessed the predictive power of the mFI-5 on postoperative outcomes.

RESULTS
Our cohort included 1692 patients with a mean age of 55.5 yr and mFI-5 of 0.80. Mean intensive care unit (ICU) and total LOS were 1.69 and 5.24 d, respectively. Mean pulmonary embolism (PE)/deep vein thrombosis (DVT), physiological/metabolic derangement, respiratory failure, and sepsis rates were 7.2%, 1.1%, 1.6%, and 1.7%, respectively. Mean total charges were $42 331. On multivariate analysis, each additional point on the mFI-5 was associated with a 0.32- and 1.38-d increase in ICU and total LOS, respectively; increased odds of PE/DVT (odds ratio (OR): 1.50), physiological/metabolic derangement (OR: 3.66), respiratory failure (OR: 1.55), and sepsis (OR: 2.12); and an increase in total charges of $5846.

CONCLUSION
The mFI-5 is a pragmatic and actionable tool which predicts LOS, complications, and charges in brain tumor patients. It may guide future efforts to risk-stratify patients with subsequent impact on postoperative outcomes.
Influence of restoration age on egg bank richness and composition: an ex situ experiment
Authors: Olmo Carla , Antón-Pardo MarÍa , Ortells Raquel , Armengol Xavier 
Published: July 2020

AbstractZooplankton community assembly after flooding in temporary ponds depends mostly on abundance and diversity of the dormant propagule bank. However, our understanding of the hatching patterns of zooplankton is imperfect. We performed an ex situ experiment to study the species composition and temporal sequence of zooplankton emergence from sediments in three ponds that were restored at different times: 1998, 2003 and 2007. The patterns of species hatching observed in our microcosms were compared with the emergent zooplankton community of their equivalent, synchronically inundated ponds. An escalation in species richness and a delay in hatching time were detected with increasing restoration age. In addition, some discrepancies between the egg bank and active populations were observed, especially in the oldest pond. This study illustrates the use of hatching experiments in comparing ponds with different characteristics. Nevertheless, egg bank hatching and water column sampling should complement each other in order to afford a full reflection of past diversity and contribute to a better understanding of the efficiency of restoration practices.
The impact of COVID-19 on Bangladeshi readymade garment (RMG) workers
Authors: Kabir Humayun , Maple Myfanwy , Usher Kim 
Published: July 2020

Abstract
This paper describes the potential impact of the coronavirus disease 2019 (COVID-19) pandemic on the readymade garment (RMG) workers of Bangladesh. It articulates the RMG workers’ existing vulnerability during the COVID-19 pandemic based on currently available evidence and personal conversations/communications with RMG workers. COVID-19 has already impacted RMG workers’ health (both physical and mental health status) and wellbeing, and resulted in loss of employment. We argue that the COVID-19 pandemic will have long-lasting effects on the garment workers, especially related to their health issues, financial hardship and inability to pay for essentials such as food, and future employment opportunities. The stakeholders (such as the international retailers/brands, Bangladesh Garment Manufacturers and Exporters Association, Government of Bangladesh) responsible for the global supply chain RMG factories should reconsider the health and overall wellbeing needs of the RMG workers during the ongoing COVID-19 pandemic.
A BESSEL DELTA METHOD AND EXPONENTIAL SUMS FOR GL(2)
Authors: Aggarwal Keshav , Holowinsky Roman , Lin Yongxiao , Qi Zhi 
Published: July 2020

Abstract
In this paper, we introduce a simple Bessel $\delta $-method to the theory of exponential sums for $\textrm{GL}_2$. Some results of Jutila on exponential sums are generalized in a less technical manner to holomorphic newforms of arbitrary level and nebentypus. In particular, this gives a short proof for the Weyl-type subconvex bound in the $t$-aspect for the associated $L$-functions.
Proximal Femoral Shortening and Varus Collapse After Fixation of “Stable” Pertrochanteric Femur Fractures
Authors: Ciufo David J. , Ketz John P. 
Published: July 2020

Objectives:
To evaluate and compare femoral neck shortening and varus collapse in stable pertrochanteric femur fractures treated with sliding hip screws (SHSs) or cephalomedullary nails (CMNs).

Design:
Retrospective review.

Setting:
Academic medical center.

Patients:
A total of 290 patients were included in the study. The average age was 82 years, and most were women. All sustained low-energy pertrochanteric femur fractures (OTA/AO A1.1, 1.2, 1.3, 2.2) treated operatively with SHSs or CMNs. Minimum radiographic follow-up was 3 months, with an average of 28 (range 3–162) months.

Intervention:
CMN or SHS fixation.

Main Outcome Measures:
Varus collapse of the femoral neck-shaft angle and proximal femoral shortening.

Results:
Both implants allowed some varus collapse. Univariate analysis demonstrated a significantly greater portion of patients with SHSs progressed to varus collapse >5 degrees (P = 0.02), mild horizontal shortening >5 mm (P < 0.01), and severe horizontal shortening >10 mm (P < 0.01). There was no statistical difference in vertical shortening (P = 0.3). There was no difference in implant failure (P = 0.5), with failure rates of 3% for cephalomedullary implants and 5% for SHS constructs.

Conclusions:
The SHS group experienced greater varus collapse and horizontal shortening. There was no difference in overall implant failure. These findings suggest that the CMN is a superior construct for maintenance of reduction in stable pertrochanteric fractures, which may lead to improved functional outcomes as patients recover.

Level of Evidence:
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Efficacy of a Novel Ophthalmic Antimicrobial Drug Combination Toward a Large Panel of Staphylococcus aureus Clinical Ocular Isolates From Around the World
Authors: Laskey Emily , Chen Yimin , Sohn Michael B. , Gruber Emma , Chojnacki Michaelle , Wozniak Rachel A. F. 
Published: July 2020

Purpose:

Staphylococcus aureus is a leading cause of keratitis requiring urgent antimicrobial treatment. However, rising antibiotic resistance has rendered current ophthalmic antibiotics increasingly ineffective. First, a diverse, ocular S. aureus strain set was evaluated for resistance to 6 commonly used ophthalmic antibiotics. Next, a recently discovered antimicrobial drug combination containing polymyxin B/trimethoprim (PT) + rifampin that displayed impressive efficacy toward S. aureus in both in vitro and in vivo studies was evaluated as a potential novel keratitis therapeutic through testing this combination's efficacy against the clinical strain set.

Methods:
A total of 163 S. aureus isolates were collected either commercially or from the Flaum Eye Institute, University of Rochester. The minimum inhibitory concentrations of moxifloxacin, levofloxacin, vancomycin, erythromycin, tobramycin, rifampin, and PT were determined for the entire strain set to establish the incidence of resistance to current treatment options among a contemporary clinical isolate set and compared with the performance of PT + rifampin.

Results:
Among all 163 isolates tested, high rates of antibiotic resistance were found toward erythromycin (69% resistance), moxifloxacin (33%), levofloxacin (40%), and tobramycin (17%). Conversely, the entire strain set, including multidrug resistant isolates, was sensitive to PT + rifampin, demonstrating the potency of this combination.

Conclusions:
We established that antibiotic resistance is pervasive among clinical S. aureus isolates, underscoring the concern for the effectiveness of current ophthalmic antibiotics. The drug combination of PT + rifampin, however, eradicated 100% of isolates tested, demonstrating the ability to overcome existing circulating resistance factors, and as such, might represent a promising therapeutic for S. aureus keratitis.
Facing SARS-CoV-2 Pandemic at a COVID-19 Regional Children’s Hospital in Italy
Authors: Ciofi degli Atti Marta Luisa , Campana Andrea , Muda Andrea Onetti , Concato Carlo , Ravà Lucilla , Ricotta Lara , Reale Antonino , Barbieri Maria , D’Argenio Patrizia , Lancella Laura , Villani Alberto , Raponi Massimiliano 
Published: July 2020

Background:
In Italy, the response to coronavirus disease 2019 (COVID-19) pandemic upgraded from social distancing on February 23, 2020, to national lockdown on March 11, 2020. We described how the pandemic affected a tertiary care children hospital with a dedicated COVID-19 regional center.

Methods:
We analyzed the characteristics of emergency department (ED) visits, urgent hospitalizations and severe acute respiratory syndrome (SARS)-COV-2 reverse transcription-polymerase chain reaction testing, and COVID-19 patients across 3 response phases: before the first Italian case, before national lockdown and during lockdown.

Results:
ED visits decreased from a daily mean of 239.1 before the first COVID-19 Italian case, to 79.6 during lockdown; urgent hospitalizations decreased from 30.6 to 21.2. As of April 20, 2020, 1970 persons were tested for SARS-CoV-2 reverse transcription-polymerase chain reaction and 2.6% were positive. Positive rates were 1.2% in the ED, 21.1% in the COVID center and 0.5% in other wards. The median age of COVID-19 patients (N = 33) was 6.7 years, 27% had coexisting conditions and 79% were related to family clusters.

Conclusions:
The pandemic strongly impacted on the use of hospital services, with a 67% reduction in ED visits and a 31% reduction in urgent hospitalizations. Separating the flows of suspected patients from all other patients, and centralization of suspected and confirmed cases in the COVID center enabled to control the risk of nosocomial SARS-CoV-2 transmission. Delay in hospital use for urgent care must be avoided, and clear communication on infection prevention and control must be provided to families. Further studies are needed to assess how the reduction in hospital use affected children healthcare needs during the pandemic.
The optimal duration of dual antiplatelet therapy in East Asian patients undergoing percutaneous coronary intervention with drug-eluting stents: a meta-analysis of randomized trials
Authors: Sun Yuchao , Liu Xiaohua , Xu Yizhou 
Published: July 2020

Objective
The optimal duration of dual antiplatelet therapy (DAPT) is still controversial among East Asians. This meta-analysis was designed to evaluate the efficacy and safety of short-term (≤6 months) vs. long-term (≥12 months) DAPT in East Asians undergoing percutaneous coronary intervention (PCI) with drug-eluting stent (DES).

Methods
PubMed, Embase, Web of Science and the Cochrane Library were searched for articles published up to 30 March 2020. Then meta-analysis was performed using RevMan 5.3 software.

Results
Nine studies with a total of 20 177 East Asian patients were included in this meta-analysis. In East Asian patients, short-term DAPT was associated with a lower incidence of major bleeding [odds ratio (OR) = 0.70, 95% confidence interval (CI) (0.49, 0.99), P = 0.04]. In the newer-generation DES subgroup, short-term DAPT was no less effective than long-term DAPT and resulted in a lower incidence of major bleeding [OR = 0.69, 95% CI (0.49, 0.98), P = 0.04]. In the subgroup of patients with acute coronary syndrome, there was no significant difference in the incidence of cardiac death, net adverse clinical and cerebral events (NACCE) and major bleeding between short-term and long-term DAPT. It was worth noting that in the subgroup of patients with diabetes mellitus, short-term DAPT was associated with a higher incidence of myocardial infarction [OR = 2.64, 95% CI (1.19, 5.88), P = 0.02] and NACCE [OR = 1.92, 95% CI (1.07, 3.43), P = 0.03].

Conclusion
The short-term DAPT (≤6 months) might be a better choice for East Asian patients undergoing PCI with DES, especially the newer-generation DES. However, for high-risk patients such as diabetes, the analysis supported the longer DAPT.
Do Water-aided Techniques Improve Serrated Polyp Detection Rate During Colonoscopy?
Authors: Aziz Muhammad , Mehta Tej I. , Weissman Simcha , Sharma Sachit , Fatima Rawish , Khan Zubair , Dasari Chandra S. , Lee-Smith Wade , Nawras Ali , Adler Douglas G. 
Published: July 2020

Background and Study Aims:
The utility of water-aided techniques (WT): water exchange (WE) and water immersion (WI) have been studied extensively in the literature for improving colonoscopy outcome metrics such as adenoma detection rate. Serrated polyps owing to their location and appearance have a high miss rate. The authors performed a systematic review and meta-analysis of studies comparing WT with the standard gas-assisted (GA) method to determine if there was any impact on serrated polyp detection rate (SPDR) and sessile serrated polyp detection rate.

Methods:
The following databases were queried for this systematic review: Medline, EMBASE, Cochrane Library, CINAHL, and Web of Sciences. The authors only included randomized controlled trials (RCTs). The primary outcome was SPDR and secondary outcomes were sessile serrated polyp detection rate and cecal intubation rate. Risk ratios (RRs) were calculated for each outcome. A P-value <0.05 was considered to be statistically significant.

Results:
A total of 4 RCTs (5 arms) with 5306 patients (2571 in the GA group and 2735 in the WT group) were included. The SPDR was significantly increased for the WT group compared with GA (6.1% vs. 3.8%; RR, 1.63; 95% confidence interval, 1.24-2.13; P<0.001; I
2=22.7%). A subgroup analysis for WE technique also demonstrated improved SPDR compared with the GA method (4.9% vs. 3.2%; RR, 1.57; 95% confidence interval, 1.15-2.14; P=0.004; I
2=6.1%).

Conclusions:
WT, particularly, the WE method results in improved SPDR. This technique should be encouraged in a clinical setting to detect these polyps to prevent interval colorectal cancer.
Quantitative Analysis of Intramucosal Mast Cells in Irritable Bowel Syndrome
Authors: Fan Lifang , Wong Mary , Fan Xuemo (Sean) , Hong Yuntian , Sun Kongliang , Jiang Congqing , Xie Xiaoyu , Wang Hanlin L. 
Published: July 2020

Goal:
We aimed to study the density of intramucosal mast cells in histologically normal colonic mucosa biopsied from patients with a clinical diagnosis of irritable bowel syndrome (IBS).

Background:
Mast cell activation has been thought to implicate in the pathogenesis of inflammatory bowel disease (IBD). Whether it serves a role in the pathogenesis of IBS remains controversial.

Study:
A total of 127 colonoscopic mucosal biopsies were immunohistochemically stained, including 51 IBS, 66 IBD, and 10 normal control samples. Intact mast cells were quantified in 3 high power fields (HPF) in areas showing the highest density.

Results:
CD117 was sensitive in detecting mast cells in colonic mucosa. The mast cell counts in all biopsies ranged from 2 to 60 per HPF (mean=17.5±7.2). The density of intramucosal mast cells were similar among IBS, IBD and normal control groups (P=0.6733). IBD in remission versus IBS (17.1±8.0 vs. 18.1±7.0; P=0.4804), Crohn disease versus ulcerative colitis (17.1±10.4 vs. 17.2±5.2; P=0.9463), IBS with diarrhea versus without diarrhea (19.5±6.3 vs. 16.8±6.9; P=0.1404). Forty biopsies (31.5%) showing ≥20 mast cells per HPF appeared to equally distribute among various disease groups (P=0.7283).

Conclusions:
There is no significant difference in the number of intramucosal mast cells between IBS and IBD that show normal colonic biopsies. In IBS patients, the number of intramucosal mast cell does not correlate with symptoms. The mast cell count (≥20/HPF) is not a reliable criterion for the diagnosis of IBS or for the distinction between patients with IBS and those with IBD in remission.
COVID-19 and liver injury: a meta-analysis
Authors: Wijarnpreecha Karn , Ungprasert Patompong , Panjawatanan Panadeekarn , Harnois Denise M. , Zaver Himesh B. , Ahmed Aijaz , Kim Donghee 
Published: July 2020

Background/aims
The number of cases with coronavirus disease 2019 (COVID-19) has exceeded seven million worldwide. However, the data describing the global prevalence of liver injury associated with COVID-19 is lacking secondary to the novelty of this ongoing pandemic. Therefore, we conducted a meta-analysis to determine the association between COVID-19 and liver injury.

Methods
A systematic literature search of indexed databases including, PubMed, Medline, and Embase databases from inception to 14 April 2020, was used to identify studies that reported data of liver chemistry in patients diagnosed with COVID 19. The overall prevalence of abnormal liver chemistry and relevant 95% confidence interval was used to estimate the pooled results studies.

Results
Sixty-four studies with 11 245 patients with COVID-19 were included. The pattern of abnormal liver enzymes was notable for higher aspartate aminotransferase (AST) than alanine aminotransferase (ALT) levels. The overall global prevalence of elevated AST, ALT, total bilirubin, gamma-glutamyltransferase (GGT), and alkaline phosphatase was 23.2, 21.2, 9.7, 15.0, and 4.0%, respectively. The prevalence of elevated AST was substantially higher among those with severe cases (45.5%) compared to non-severe cases (15.0%). Co-existing chronic liver disease presented up to 37.6% of patients with COVID-19.

Conclusion
A fourth of COVID-19 patients had elevated liver enzymes and associated with disease severity. Our study may be used as a guide for clinicians and epidemiologists to proactively identify other sources of injury and illness in patients diagnosed with COVID-19. Intensive monitoring for liver injury may be needed in cases with severe COVID-19.