bluuebunny/crossref_metadata_2025 huggingface dataset:
Object Classificators Using the AdaBoost Algorithm and Neural Networks
Authors: Stadnik Alexey V. , Sazhin Pavel S. , Hnatic Slavomir
Published: February 2018

The construction of image object detectors is still a relevant task, due to dynamic developments in the field of computer vision. In this work, we combined neural network technologies with existing data processing algorithms to obtain effective object classifiers. We demonstrate our approach on the example of face detection.
Medical Management of Portal Hypertension and Its Complications
Authors: Singh Tavankit , McCullough Arthur
Published: February 2018

Portal hypertension, most commonly caused by cirrhosis, is defined as an elevated hepatic venous pressure gradient that can lead to complications including ascites, hepatic, esophageal/gastric varices, hepatic encephalopathy, and hepatorenal syndrome. While these complications are initially managed by medical and endoscopic treatments, progressive decompensation of liver disease may lead to liver transplantation.
Morphine Analgesia Pre-PPCI Is Associated with Prothrombotic State, Reduced Spontaneous Reperfusion and Greater Infarct Size
Authors: Farag Mohamed , Spinthakis Nikolaos , Srinivasan Manivannan , Sullivan Keith , Wellsted David , Gorog Diana
Published: February 2018

The emergency management of ST-elevation myocardial infarction (STEMI) involves treatment with dual-antiplatelet therapy (DAPT) and primary percutaneous coronary intervention (PPCI). Pain is generally treated with opiates, which may delay gastric transit and reduce DAPT absorption. We sought to assess the effect of morphine on reperfusion, infarct size and thrombotic status in 300 patients presenting for PPCI. Morphine was given in a non-randomized fashion as required by emergency teams en route to the heart attack centre. All patients received DAPT and PPCI according to standard care, with optional glycoprotein IIb/IIIa inhibitor (GPI) use. Patients were assessed for ST-segment resolution, coronary flow, thrombotic status and peak troponin. Patients receiving morphine (n = 218; 72.7%) experienced less spontaneous ST-segment resolution pre-PPCI, lower rate of TIMI 2/3 flow in the infarct-related artery pre-PPCI and higher peak troponin level post-PPCI (median [interquartile range]; 1,906 [1,002–4,398] vs. 1,268 [249–2,920] ng/L; p = 0.016) than those who did not. Patients receiving morphine exhibited significantly enhanced platelet reactivity and impaired endogenous fibrinolysis on arrival, compared with no-morphine patients. Morphine administration was an independent predictor of failure of spontaneous ST-segment resolution after adjustment for other variables (odds ratio: 0.26; confidence interval: 0.08–0.84; p = 0.025). Among patients receiving GPI, there was no difference in pre-PPCI flow or peak troponin according to morphine use, suggesting that the adverse effects of morphine relate to delayed DAPT absorption, which may be overcome by GPI. Our hypothesis-generating data suggest that morphine use in STEMI is associated with enhanced platelet reactivity, reduced spontaneous myocardial reperfusion (pre-PPCI) and larger infarct size, and these adverse effects may be influenced by GPI use.

Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT02562690.
TIPS in the Treatment of Variceal Bleeding
Authors: Morrison Joseph , Lipnik Andrew , Gaba Ron
Published: February 2018

Variceal bleeding is a life-threatening complication of portal hypertension. In recent years, transjugular intrahepatic portosystemic shunt (TIPS) creation has cemented a role in the management of acute refractory bleeding and recurrent variceal hemorrhage. This article aims to review the use of TIPS in patients with variceal bleeding, with a focus on accepted procedure indications, patient selection criteria, TIPS technique, clinical outcomes, and contemporary issues, such as early TIPS in acute variceal hemorrhage, the role of adjuvant embolotherapy, and TIPS utility for gastric varices.
Early Transjugular Intrahepatic Portosystemic Shunt (TIPS) Placement in Patients with Cirrhosis and Variceal Bleeding
Authors: Fortune Brett , Sands Mark , Bayona-Molano Maria , Kapoor Baljendra , Lang Min
Published: February 2018

The placement of a transjugular intrahepatic portosystemic shunt (TIPS) has been traditionally used as a rescue treatment for uncontrolled or recurrent acute variceal bleeding (AVB) in patients with cirrhosis. However, more contemporary studies are revealing that early or ‘pre-emptive’ TIPS placement (performed within 24–72 h of AVB presentation) significantly controls bleeding, prevents rebleeding, and improves survival in selected patients when compared with standard pharmacological and endoscopic therapies. Furthermore, the use of early TIPS did not translate to an increased risk of hepatic encephalopathy (HE) for this population. Proper patient selection for early TIPS is paramount, as the procedure is unlikely to benefit patients with advanced decompensated cirrhosis (Child–Turcotte–Pugh [CTP] class C, score > 13) or patients who do not carry high risk with only mild hepatic dysfunction (Child-Turcotte-Pugh class A). Finally, while the current results for early TIPS are promising, further prospective studies are needed to confirm these findings before early TIPS can be widely adopted.
Investigation of Parvovirus B19 IgM and IgG Positivity Rates in Pediatric Hematology Patients
Authors: Uğur Ayşe , Özdemir Mehmet , Feyzioğlu Bahadır , Baykan Mahmut , Görkem Aysun
Published: February 2018

Human parvovirus B19 is a frequent etiologic agent causing erythema infectiosum in children. It has recently been suggested that parvovirus B19 may be latent after infection and cause reactive infections especially in immunosuppressed patients with hematological problems. In this study, we aimed to investigate the parvovirus B19 immunoglobulin M (IgM) and immunoglobulin G (IgG) seropositivity rates of patients evaluated in a pediatric hematology clinic. We retrospectively screened the laboratory results of parvovirus B19 IgM and IgG antibody assays of children less than 18 years, who consulted pediatric in-and-outpatient clinics between 2013 and 2016. Parvovirus B19 IgM and IgG antibodies were investigated in serum samples by using enzyme-linked immunosorbent assay method in the Medical Microbiology Laboratory. Parvovirus B19 IgM antibodies were detected in 109 of 602 patients attending pediatric hematology clinics (18.1%). Parvovirus B19 IgG antibody was detected in 244 of 952 patients attending pediatric hematology clinics (25.6%). Parvovirus B19 IgM and IgG positivity in samples from pediatric in-and-outpatient clinics other than pediatric hematology were 2.8% and 35.7%, respectively. Parvovirus IgM and IgG positivity in serum samples sent from the pediatric hematology clinic and outpatients was statistically significant compared with those sent from pediatric clinics other than pediatric hematology (p = 0.0001 and p = 0.0008, respectively). The higher detection rate of serum parvovirus B19 IgM positivity in patients under the follow-up of pediatric hematology clinics suggests that immune suppression-related viral reinfection or persistence may occur in these patients.
BET bromodomain proteins regulate enhancer function during adipogenesis
Authors: Brown Jonathan D. , Feldman Zachary B. , Doherty Sean P. , Reyes Jaime M. , Rahl Peter B. , Lin Charles Y. , Sheng Quanhu , Duan Qiong , Federation Alexander J. , Kung Andrew L. , Haldar Saptarsi M. , Young Richard A. , Plutzky Jorge , Bradner James E.
Published: February 2018

Developmental transitions are guided by master regulatory transcription factors. During adipogenesis, a transcriptional cascade culminates in the expression of PPARγ and C/EBPα, which orchestrate activation of the adipocyte gene expression program. However, the coactivators controlling PPARγ and C/EBPα expression are less well characterized. Here, we show the bromodomain-containing protein, BRD4, regulates transcription of PPARγ and C/EBPα. Analysis of BRD4 chromatin occupancy reveals that induction of adipogenesis in 3T3L1 fibroblasts provokes dynamic redistribution of BRD4 to de novo super-enhancers proximal to genes controlling adipocyte differentiation. Inhibition of the bromodomain and extraterminal domain (BET) family of bromodomain-containing proteins impedes BRD4 occupancy at these de novo enhancers and disrupts transcription of
Pparg
and
Cebpa
, thereby blocking adipogenesis. Furthermore, silencing of these BRD4-occupied distal regulatory elements at the
Pparg
locus by CRISPRi demonstrates a critical role for these enhancers in the control of
Pparg
gene expression and adipogenesis in 3T3L1s. Together, these data establish BET bromodomain proteins as time- and context-dependent coactivators of the adipocyte cell state transition.
Placental physiology monitored by hyperpolarized dynamic
13
C magnetic resonance
Authors: Markovic Stefan , Fages Anne , Roussel Tangi , Hadas Ron , Brandis Alexander , Neeman Michal , Frydman Lucio
Published: February 2018

Significance

The placenta mediates the transfer of metabolites and nutrients, and its dysfunction leads to clinical syndromes that jeopardize both the fetus and mother. Current methods for assessing placental transport and metabolism in vivo are limited; the goal of this study is to validate the potential of minimally invasive technologies based on high-sensitivity, hyperpolarized
13
C MRI. Distinct placental crossing features were observed when administering different hyperpolarized metabolites to near-term rodents. In particular, [1-
13
C]pyruvate was observed to clearly localize in the placenta and to efficiently metabolize into lactate in healthy animals. By contrast, though transport appeared normal, a marked decrease in placental metabolism was observed in preeclamptic models. This opens avenues to diagnose placental disorders, which could translate into humans.
Moduli spaces of invariant metrics of positive scalar curvature on quasitoric manifolds
Authors: Wiemeler Michael
Published: February 2018

We show that the higher homotopy groups of the moduli space of torus-invariant positive scalar curvature metrics on certain quasitoric manifolds are nontrivial.
Hard Lefschetz theorem for Vaisman manifolds
Authors: Cappelletti-Montano Beniamino , De Nicola Antonio , Marrero Juan Carlos , Yudin Ivan
Published: February 2018

We establish a Hard Lefschetz Theorem for the de Rham cohomology of compact Vaisman manifolds. A similar result is proved for the basic cohomology with respect to the Lee vector field. Motivated by these results, we introduce the notions of a Lefschetz and of a basic Lefschetz locally conformal symplectic (l.c.s.) manifold of the first kind. We prove that the two notions are equivalent if there exists a Riemannian metric such that the Lee vector field is unitary and parallel and its metric dual

1
1

-form coincides with the Lee

1
1

-form. Finally, we discuss several examples of compact l.c.s. manifolds of the first kind which do not admit compatible Vaisman metrics.
Invite your representative to work. Change the world. Here’s how.
Authors: Montell Denise J.
Published: February 2018

Today’s political climate can seem hostile to science. Alternative facts, climate change denial, and relabeling of actual news as fake news are discouraging phenomena for sure. But these trends make it more important than ever to engage our politicians. Take heart! There is something you can do. You can show your representatives firsthand the amazing things you do, evidence of the economic engine that your activities generate, and the real people behind the discoveries. I did, and it was fun. We invited our congressman to the University of California, Santa Barbara (UCSB), and he accepted! For 2 hours, we explained and demonstrated efforts to cure blindness using stem cells, the medical implications of the discovery that cells can recover from the brink of death, a mosquito lab striving to eliminate insect-borne disease, and an Alzheimer’s disease laboratory. Salud Carbajal peered through a microscope and met real scientists. Before his visit, he did not know what a postdoctoral fellow was, much less what stem cells look like. When he left he knew our names, how much money we bring into his district, and how important National Institutes of Health funding and international mobility are to our enterprise. Although I live in the United States, this approach should also apply to other democratic countries. If each of us converts one representative into a science champion, we can change the world.
‘The Great Blow’ and the Politics of Popular Royalism in Civil War Norwich
Authors: Hopper Andrew
Published: February 2018

This article explores popular politics and royalism during the English Civil Wars through the reaction of magistrates to the riot in Norwich on 24 April 1648 that was referred to by contemporaries as the ‘mutiny’ or the ‘Great Blow’. On the eve of the Second Civil War, this confrontation between urban rioters and New Model Army troopers led to the largest explosion of gunpowder in seventeenth-century England, when ninety-eight barrels were ignited at the Committee House. The article analyses the 278 witness statements that were produced as part of the judicial inquest, making this the best documented provincial riot of the early modern period. These previously neglected proceedings can do much to advance our understanding of popular politics, royalism and urban culture. Therefore the article focuses on how the rioters mobilised and generated crowds through petitioning, subscription, print, preaching, rumour, health-drinking, seditious words, and gestures. It assesses participants’ social origins and places them within contrasting local religious and political cultures in a battle for control of the key public spaces of the city. The seditious words revealed in the testimonies cannot be dismissed as merely anti-parliamentarian, and in many cases illuminate how a politics of popular royalism was revived in the city. The episode highlights how both national and local, and elite and popular politics overlapped and were entwined by civil war.
Danger Signals in the ICU
Authors: Schenck Edward J. , Ma Kevin C. , Murthy Santosh B. , Choi Augustine M. K.
Published: February 2018

Objectives:

Sterile and infectious critical illnesses often result in vasoplegic shock and a robust systemic inflammatory response that are similar in presentation. The innate immune system is at the center of the response to both infectious and traumatic insults. Damage-associated molecular patterns are small molecules that are released from stressed or dying cells. Damage-associated molecular patterns activate pattern recognition receptors and coordinate the leading edge of the innate immune response. This review introduces the concept of damage-associated molecular patterns and how they activate a systemic inflammatory response, specifically in trauma, neurologic injury, and infection. It also explores how, when carried to extremes, damage-associated molecular patterns may even perpetuate multisystem organ failure.

Data Sources:

Basic and clinical studies were obtained from a PubMed search through August 2017.

Study Selection:

Articles considered include original articles, review articles, and conference proceedings.

Data Extraction:

An analysis of scientific, peer-reviewed data was performed. High quality preclinical and clinical studies adjudicated by the authors were included and summarized.

Data Synthesis:

Pattern recognition receptors respond to damage-associated molecular patterns and then activate inflammatory pathways. Damage-associated molecular patterns have been linked to the recruitment of sentinel leukocytes and the initiation of the inflammatory cascade. Damage-associated molecular patterns have been linked to many conditions in critical care illnesses. Preclinical models have added insight into how they may mediate distant organ dysfunction.

Conclusions:

Damage-associated molecular pattern activation and release is an important research for intensive care practitioners. It will add to our understanding of the phase and state of the innate immune response to an insult. Early work is encouraging. However, only with improved understanding of damage-associated molecular pattern activation and function, we can perhaps hope to target damage-associated molecular patterns as diagnostic and/or therapeutic modalities in the future.
NEWLY DIAGNOSED ASYMPTOMATIC RETINAL ASTROCYTIC HAMARTOMA IN AN OLDER ADULT
Authors: Gündüz A. Kaan , Shields Carol L. , Çöndü Gökçen , Gürsel Ragip
Published: February 2018

Background:

To report a coincidentally discovered retinal astrocytic hamartoma in an asymptomatic older woman with no history of tuberous sclerosis or neurofibromatosis.

Methods:

A 63-year-old Turkish woman underwent routine ophthalmic examination.

Results:

Visual acuity was 20/25 in each eye. On fundus examination, the right eye showed a flat yellow-white superficial retinal lesion in the inferotemporal macula and measuring 1 mm in diameter. The lesion was unmeasurable using B-mode ultrasonography. Spectral domain optical coherence tomography revealed the mass with thickening in the retinal nerve fiber layer, with minor disorganization of the underlying retina and no retinal or vitreoretinal traction. Fluorescein angiography disclosed the mass as early isofluorescence with late mild hyperfluorescence, without leakage. Findings in the left eye were normal. Based on the clinical and imaging results, a diagnosis of noncalcified small retinal astrocytic hamartoma was rendered. The lesion remained unchanged at 1-year follow-up.

Conclusion:

Small coincidentally discovered retinal astrocytic hamartomas in older patients can be difficult to diagnose and possibly cause diagnostic confusion with other conditions including myelinated nerve fiber and cotton wool spot. Retinal astrocytic hamartoma is characterized by thickening of the retinal nerve fiber layer and mild compression and disorganization of the underlying retinal layers on spectral domain optical coherence tomography.
PROGRESSION OF RETINAL ISCHEMIA IN A CASE OF MACULAR TELANGIECTASIA TYPE 1 AFTER RANIBIZUMAB INJECTION: OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FINDINGS
Authors: Lorusso Massimo , Zito Roberta , Nikolopoulou Eleni , Micelli Ferrari Luisa , Cicinelli Maria Vittoria , Querques Giuseppe , Micelli Ferrari Tommaso
Published: February 2018

Purpose:

To describe a case of a 68-year-old man with macular telangiectasia (MacTel) Type 1 in the right eye, showing an increase in capillary ischemia after intravitreal ranibizumab.

Methods:

The patient underwent complete ophthalmologic evaluation, including best-corrected visual acuity, intraocular pressure, anterior segment and fundus examination, optical coherence tomography (OCT), and OCT angiography at baseline and on each visit. Fluorescein angiography was performed at baseline. The patient was followed up on monthly bases for 22 months.

Results:

The patient presented a best-corrected visual acuity of 20/80 in the right eye and of 20/25 in the left eye at baseline. In the right eye, the fluorescein angiography images showed perifoveal capillary ectasia, late-frames dye leakage, and enlargement of the foveal avascular zone. The OCT showed intraretinal pseudocysts and microaneurysms, and the OCT angiography showed vascular rarefaction, capillary dropout, and capillary ectasia of the superficial plexus. After 16 months of follow-up and four ranibizumab injections, the best-corrected visual acuity was 20/60, and the OCT angiography disclosed a further enlargement of the foveal avascular zone area and increased capillary obliteration in the perifoveal nasal area.

Conclusion:

Optical coherence tomography angiography may represent an indispensable diagnostic technique, complementary to traditional imaging, in the evaluation of the effects of anti–vascular endothelial growth factor therapy in patients with MacTel Type 1.
Are graft-versus-host-disease patients missing out on the vital occupational therapy services? a systematic review
Authors: Bakhsh Hadeel R. , Mohammed Jaleel , Hashmi Shahrukh K.
Published: February 2018

The aim of this review is to show the importance of occupational therapy/hand therapy for chronic graft-versus-host-disease (GVHD) patients and to outline the current state of the literature. GVHD of the hand can cause functional loss, reduced activities of daily life, poor social interaction, and loss of income because of limitations in work. Hand therapy, which is a specialty practised by both occupational therapists and physical therapists, has been proven to be an effective approach for hand-related musculoskeletal disorders; however, the literature search suggests that it is an underutilized specialty around the world. An electronic search was performed from 1997 to 2017 using OneFile (GALE), Medline/PubMed (NLM), Scopus (Elsevier), Science Citation Index Expanded (Web of Science), ProQuest Central (New), ProQuest Hospital Collection, Health Reference Center Academic (Gale), Health Research Premium Collection, Science Direct Journals (Elsevier), ProQuest Health & Medical Complete, Medical Database, Wiley Online Library, and SciTech Premium Collection for the period from 1994 to April 2017. Only randomized-controlled trials involving occupational therapy or hand therapy in patients with chronic hand GVHD were included in the final analysis. The search was limited to articles in English. Two reviewers independently assessed the methodological quality and extracted the data. The JADAD scoring method was used to score the articles. After the duplicates were excluded, 5466 articles were identified by the electronic database search for screening, out of which 5465 articles were excluded after reviewing. One article was further excluded on obtaining the full text as it was a case study. Hand therapy specialty, although a vital part of the recovery process for the patients with hand GVHD, is an underutilized specialty and well-designed trials are urgently needed for musculoskeletal hand GVHD, especially for focused hand therapy interventions.
Context-Appropriate Interventions to Prevent Syphilis: A Narrative Review
Authors: Peterman Thomas A. , Cha Susan
Published: February 2018

Background

The success of an intervention to prevent syphilis will depend on the context and the goal of the intervention. To help programs choose interventions, we reviewed major changes in context and types of interventions that may be effective.

Methods

We reviewed the literature on the changing context of syphilis in the United States and interventions to prevent syphilis, focusing on articles that included evidence of effectiveness.

Results

Populations acquiring syphilis are constantly changing. Currently, incidence is very high among men who have sex with men (MSM). Among adults, late disease caused by syphilis has become rare. Congenital syphilis incidence has been low but is increasing, and morbidity and mortality remain high when babies are infected. Congenital syphilis now causes more deaths than syphilis among adults.

Routine screening of MSM can identify and treat infections before they progress to disease (secondary prevention). Screening rates are highest when done as part of routine standing orders. Partner notification effectiveness has decreased, partly because many partners are anonymous. Most congenital syphilis can be prevented by screening pregnant women; it has been eliminated in areas where intense primary prevention efforts eliminated syphilis among women.

Conclusions

So far, no program has stopped the increasing rates of infection among MSM, but secondary prevention efforts have prevented most disability. Congenital syphilis is increasing, and can be decreased by screening pregnant women and stopped by intensive efforts to prevent infection among women.
A family of wave equations with some remarkable properties
Authors: da Silva Priscila Leal , Freire Igor Leite , Sampaio Júlio Cesar Santos
Published: February 2018

We consider a family of homogeneous nonlinear dispersive equations with two arbitrary parameters. Conservation laws are established from the point symmetries and imply that the whole family admits square integrable solutions. Recursion operators are found for two members of the family investigated. For one of them, a Lax pair is also obtained, proving its complete integrability. From the Lax pair, we construct a Miura-type transformation relating the original equation to the Korteweg–de Vries (KdV) equation. This transformation, on the other hand, enables us to obtain solutions of the equation from the kernel of a Schrödinger operator with potential parametrized by the solutions of the KdV equation. In particular, this allows us to exhibit a kink solution to the completely integrable equation from the 1-soliton solution of the KdV equation. Finally, peakon-type solutions are also found for a certain choice of the parameters, although for this particular case the equation is reduced to a homogeneous second-order nonlinear evolution equation.
Landscape configurational heterogeneity by small-scale agriculture, not crop diversity, maintains pollinators and plant reproduction in western Europe
Authors: Hass Annika L. , Kormann Urs G. , Tscharntke Teja , Clough Yann , Baillod Aliette Bosem , Sirami Clélia , Fahrig Lenore , Martin Jean-Louis , Baudry Jacques , Bertrand Colette , Bosch Jordi , Brotons Lluís , Burel Françoise , Georges Romain , Giralt David , Marcos-García María Á. , Ricarte Antonio , Siriwardena Gavin , Batáry Péter
Published: February 2018

Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish (Raphanus sativus), probably through enhanced connectivity. In particular, we demonstrate the importance of crop–crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop–crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management.
Ocean acidification but not warming alters sex determination in the Sydney rock oyster,
Saccostrea glomerata
Authors: Parker Laura M. , O'Connor Wayne A. , Byrne Maria , Dove Michael , Coleman Ross A. , Pörtner Hans-O , Scanes Elliot , Virtue Patti , Gibbs Mitchell , Ross Pauline M.
Published: February 2018

Whether sex determination of marine organisms can be altered by ocean acidification and warming during this century remains a significant, unanswered question. Here, we show that exposure of the protandric hermaphrodite oyster,
Saccostrea glomerata
to ocean acidification, but not warming, alters sex determination resulting in changes in sex ratios. After just one reproductive cycle there were 16% more females than males. The rate of gametogenesis, gonad area, fecundity, shell length, extracellular pH and survival decreased in response to ocean acidification. Warming as a sole stressor slightly increased the rate of gametogenesis, gonad area and fecundity, but this increase was masked by the impact of ocean acidification at a level predicted for this century. Alterations to sex determination, sex ratios and reproductive capacity will have flow on effects to reduce larval supply and population size of oysters and potentially other marine organisms.
Real-time fine aerosol exposures in taconite mining operations
Authors: Huynh Tran , Ramachandran Gurumurthy , Quick Harrison , Hwang Jooyeon , Raynor Peter C , Alexander Bruce H , Mandel Jeff H
Published: February 2018

Respiratory health effects such as mesothelioma, silicosis, and lung cancer have been shown to be associated with working in the taconite mining industry. Taconite workers may also have elevated risks from cardiovascular disease (CVD), although the relationship of CVD to dust exposures at these mines has not been well-studied. Motivated by evidence from environmental epidemiological studies and occupational cohorts that have implicated the effects of fine particulates with increased risk of cardiovascular diseases, we conducted an air monitoring campaign to characterize fine aerosol concentrations at 91 locations across six taconite mines using an array of direct-reading instruments to obtain measurements of mass concentrations (PM2.5 or particles with aerodynamic diameter less than 2.5 μm, and respirable particulate matter or RPM), alveolar-deposited surface area concentrations (ADSA), particle number concentrations (PN), and particle size distributions. To analyze these data, we fit a Bayesian hierarchical model with an AR(1) correlation structure to estimate exposure while accounting for temporal correlation. The highest estimated geometric means (GMs) were observed in the pelletizing and concentrating departments (pelletizing maintenance, balling drum operator, and concentrator operator) for PM2.5 and RPM. ADSA and PN generally had highest GMs in the pelletizing department, which processed large amounts of powder-like particles into iron pellets. The within-location variability (GSD_WL) generally ranged from 1 to 3 for all exposure metrics, except for a few locations which indicated changes of activities that caused the exposures to change. Between-location variability (GSD_BL) estimates were generally higher than GSD_WL, indicating larger differences in exposure levels at different locations between mines than at individual locations over the course of several hours. Ranking between PM2.5 and RPM generally agree with each other, whereas ADSA and PN were more consistent with each other, with some overlap with PM2.5and RPM. Differences in ranking these groups may have potential implication for occupational epidemiological studies that rely on exposure information to detect an exposure-response relationship for various job groups. Future epidemiological studies investigating fine aerosol exposures and health risks in occupational settings are encouraged to use multiple metrics to see how they influence health outcomes risk.
Reverse transcriptase fused CRISPR-Cas1 locus with RNA-seq expression necessitates revisiting hypothesis on acquisition of antibiotic resistance genes in multidrug-resistant Enterococcus faecalis V583
Authors: Chakraborty Sandeep
Published: February 2018

The emergence of drug-resistance in Enterococcus faecalis V583 through acquisition of resistance genes has been correlated to the absence of CRISPR-loci. Here, the presence of a bona-fide CRISPR locus in E. faecalis V583 (Accid:NC_004668.1) at 2238156 with a single 20 nt repeat is demonstrated. The presence of a putative endonuclease Cas1 13538 nucleotides away from the repeat substantiates this claim. This Cas1 (628 aa) is highly homologous (Eval:5e-34) to a Cas1 from Pseudanabaena biceps (Accid:WP 009625648.1, 697 aa), which belongs to the enigmatic family of RT-CRISPR locus. Such significant similarity to a Cas protein, the presence of a topoisomerase, other DUF (domain of unknown function) proteins as is often seen in CRISPR loci, and other hypothetical proteins indicates that this is a bona-fide CRISPR locus. Further corroboration is provided by expression of both the repeat and the Cas1 gene in existing RNA-seq data (SRX3438611). Since so little is known of even well-studied species like E. faecalis V583 having many hypothetical proteins, computational absence of evidence should not be taken as evidence of absence (both crisprfinder and PILER-CR do not report this as a CRISPR locus). It is unlikely that bacteria would completely give up defense against its primeval enemies (viruses) to bolster its fight against the newly introduced antibiotics.
Enhancer Identification using Transfer and Adversarial Deep Learning of DNA Sequences
Authors: Cohn Dikla , Zuk Or , Kaplan Tommy
Published: February 2018

Enhancer sequences regulate the expression of genes from afar by providing a binding platform for transcription factors, often in a tissue-specific or context-specific manner. Despite their importance in health and disease, our understanding of these DNA sequences, and their regulatory grammar, is limited. This impairs our ability to identify new enhancers along the genome, or to understand the effect of enhancer mutations and their role in genetic diseases.

We trained deep Convolutional Neural Networks (CNN) to identify enhancer sequences in multiple species. We used multiple biological datasets, including simulated sequences, in vivo binding data of single transcription factors and genome-wide chromatin maps of active enhancers in 17 mammalian species. Our deep networks obtained high classification accuracy by combining two training strategies: First, training on enhancers vs. non-enhancer background sequences, we identified short (1-4bp) low-complexity motifs. Second, by replacing the negative training set by adversarial k-order random shuffles of enhancer sequences (thus maintaining base composition while shuttering longer motifs, including transcription factor binding sites), we identified a set of biologically meaningful motifs, unique to enhancers. In addition, classification performance improved when combining positive data from all species together, showing a shared mammalian regulatory architecture.

Our results demonstrate that design of adversarial training data, and transfer of learned parameters between networks trained on different species/datasets improve the overall performance and capture biologically meaningful information in the parameters of the learned network.

Contact:or.zuk@mail.huji.ac.il, tommy@cs.huji.ac.il
Steering ecological-evolutionary dynamics during artificial selection of microbial communities
Authors: Xie Li , Shou Wenying
Published: February 2018

Microbial communities often perform important functions that arise from interactions among member species. Community functions can be improved via artificial selection: Many communities are repeatedly grown, mutations arise, and communities with the highest desired function are chosen to reproduce where each is partitioned into multiple offspring communities for the next cycle. Since selection efficacy is often unimpressive in published experiments and since multiple experimental parameters need to be tuned, we sought to use computer simulations to learn how to design effective selection strategies. We simulated community selection to improve a community function that requires two species and imposes a fitness cost on one of the species. This simplified case allowed us to distill community function down to two fundamental and orthogonal components: a heritable determinant and a nonheritable determinant. We then visualize a “community function landscape” relating community function to these two determinants, and demonstrate that the evolutionary trajectory on the landscape is restricted along a path designated by ecological interactions. This path can prevent the attainment of maximal community function, and trap communities in landscape locations where community function has low heritability. Exploiting these observations, we devise a species spiking approach to shift the path to improve community function heritability and consequently selection efficacy. We show that our approach is applicable to communities with complex and unknown function landscapes.
Axon Guidance Signaling Modulates Epithelial to Mesenchymal Transition in Stem Cell-Derived Retinal Pigment Epithelium
Authors: Sripathi Srinivas R. , Liu Melissa M. , Hu Ming-Wen , Wan Jun , Cheng Jie , Duan Yukan , Mertz Joseph , Wahlin Karl , Maruotti Julien , Berlinicke Cynthia A , Qian Jiang , Zack Donald J.
Published: February 2018

The critical role of epithelial to mesenchymal transition (EMT) in embryonic development, malignant transformation, and tumor progression has been well studied in normal and cancerous tissues and cells. Interestingly, EMT has also been reported to play a key role in the early progression of several retinal degenerative diseases, including scarring associated proliferative vitro-retinopathy (PVR), choroidal neo-vascularization induced “wet” age-related macular degeneration (AMD) and diabetic retinopathy (DR). Despite these studies, many questions remain unexplored regarding EMT-associated retinal pigment epithelium (RPE) degeneration and dysfunction. We hypothesize that RPE cells undergo EMT prior to cell death during the progression of atrophic “dry” AMD. Utilizing human stem cell-derived RPE (hRPE) as a model to study RPE EMT, we optimized two independent but complementary RPE EMT induction systems: 1) enzymatic dissociation of hRPE monolayer cultures and 2) co-treatment of hRPE monolayer cultures with transforming growth factor beta (TGF-β) and the inflammatory cytokine, tumor necrosis factor alpha (TNF-α). To further understand the molecular mechanisms of RPE EMT regulation, we performed an RNA-Sequencing (RNA-Seq) time course examination across 48 hours beginning with EMT induction. Our transcriptome profiling provides a comprehensive quantification of dynamic signaling events and associated biological pathways underlying RPE EMT and reveals an intriguing significance for widespread dysregulation of multiple axon guidance molecules in this process.
FemtoMAX – an X-ray beamline for structural dynamics at the short-pulse facility of MAX IV
Authors: Enquist Henrik , Jurgilaitis Andrius , Jarnac Amelie , Bengtsson Åsa U. J. , Burza Matthias , Curbis Francesca , Disch Christian , Ekström J. Carl , Harb Maher , Isaksson Lennart , Kotur Marija , Kroon David , Lindau Filip , Mansten Erik , Nygaard Jesper , Persson Anna I. H. , Pham Van Thai , Rissi Michael , Thorin Sara , Tu Chien-Ming , Wallén Erik , Wang Xiaocui , Werin Sverker , Larsson Jörgen
Published: February 2018

The FemtoMAX beamline facilitates studies of the structural dynamics of materials. Such studies are of fundamental importance for key scientific problems related to programming materials using light, enabling new storage media and new manufacturing techniques, obtaining sustainable energy by mimicking photosynthesis, and gleaning insights into chemical and biological functional dynamics. The FemtoMAX beamline utilizes the MAX IV linear accelerator as an electron source. The photon bursts have a pulse length of 100 fs, which is on the timescale of molecular vibrations, and have wavelengths matching interatomic distances (Å). The uniqueness of the beamline has called for special beamline components. This paper presents the beamline design including ultrasensitive X-ray beam-position monitors based on thin Ce:YAG screens, efficient harmonic separators and novel timing tools.
Imperatives for improving entrepreneurial behavior among females in the UAE
Authors: Jabeen Fauzia , Faisal Mohd. Nishat
Published: February 2018

Purpose

Despite various governmental efforts, female entrepreneurship in the UAE is still not a popular option among women. The purpose of this study is to identify the enablers to female entrepreneurship and to establish relationships among them.

Design/methodology/approach

This research uses a two-phased approach. In the first-phase, an empirical study on female entrepreneurs was conducted to find out the most important enablers from among a set of variables identified through a comprehensive literature review. In the second-phase, using interpretive structural modeling, a hierarchy-based model is developed among the most important enablers. Further, these enablers are also classified depending on their driving power and dependence.

Findings

Survey results indicate that female entrepreneurs consider enablers as the driving force in creating an entrepreneurial culture. Further, the hierarchy-based model developed in this research helps to identify variables that are of strategic importance and require utmost attention.

Practical implications

The framework presented in this study can be used effectively by the policymakers to develop suitable strategies for improving entrepreneurial behavior among women in the United Arab Emirates.

Originality/value

The novelty of this approach is the integration of questionnaire and interpretive structural modeling methodology and classifying enablers in four clusters. The research provides useful insights about the perception of female entrepreneurs about the entrepreneurial culture in the United Arab Emirates, and a relationship model that may serve as a decision tool for improving female entrepreneurship.
Antecedents and outcomes of job insecurity among salespeople
Authors: Bouzari Mona , Karatepe Osman M.
Published: February 2018

Purpose

The purpose of this paper is to examine the impacts of job resources, as manifested by selective staffing, training (TR), and career opportunities, on job insecurity and the influence of job insecurity on hope, job satisfaction, and creative performance. By investigating these relationships, the present study also aims to provide the managers the ways by which they can foster job resources, reduce job insecurity, and activate hope and job outcomes of their salespeople.

Design/methodology/approach

Data came from hotel salespeople in Iran. Structural equation modeling was used to test the aforesaid relationships.

Findings

The empirical data lend support to the overwhelming majority of the relationships. Specifically, job insecurity and hope act as mediators of the impacts of job resources on job satisfaction. Job satisfaction mediates the impacts of job insecurity and hope on creative performance. Contrary to what has been hypothesized, job insecurity positively influences salespeople’s hope. Such salespeople in turn exhibit higher job satisfaction. In addition, job resources do not significantly influence hope via job insecurity.

Practical implications

Management should invest in job resources to reduce job insecurity. Management should also try to hire individuals high on hope since hope is treated as a malleable variable and can be developed via TR interventions. Workshops can be organized to enable junior salespeople to learn senior salespeople’s practices regarding the solutions to new customer requests and problems.

Originality/value

Job insecurity is an endemic problem in many industries and there is a lack of empirical research about the intermediate linkage between job insecurity and employees’ job outcomes. There is also a need for more research to ascertain the factors influencing job insecurity.
Entrepreneurial intentions of surf tourists
Authors: Ratten Vanessa
Published: February 2018

Purpose

There has been an increase in surf tourism, as surfing has gained more international prominence and popularity. Many individuals travel to surf competitions as a form of leisure activity and enhance business connections. The purpose of this study is to examine the entrepreneurial intentions of tourists at a surf event by focusing on lifestyle entrepreneurs.

Design/methodology/approach

A case study methodology of the Bells Beach surf contest, Australia, was conducted via semi-structured, in-depth interviews of surf tourists to explore their entrepreneurial behaviour.

Findings

Results reveal that many surf tourists are interested in surfing as a leisure activity but others see the potential business opportunities of the sport.

Originality/value

This study fills a gap in the literature between lifestyle entrepreneurship and surf tourism by highlighting the role of entrepreneurial intentions for developing tourism business activities. Management implications for surf tourism entrepreneurs and tourism bodies are discussed along with suggestions for future research.
Chaparral bird community responses to prescribed fire and shrub removal in three management seasons
Authors: Newman Erica A. , Potts Jennifer B. , Tingley Morgan W. , Vaughn Charles , Stephens Scott L.
Published: February 2018

Chaparral, a type of shrubland common throughout the California Floristic Province, is subject to management and removal in regions where wildfire threatens human lives and property. Management practices include conducting prescribed burns outside of the historical fire season and employing mechanical fuel reduction (mastication). As the wildland–urban interface grows, particularly in coastal California, more of this ecosystem is subject to active management.

To understand the ecological implications of current California chaparral fire management practices, we studied bird species composition, abundance and foraging guilds in managed and unmanaged chaparral over 5 years. Study areas were located in Mendocino County in the coast ranges of northern California. We contrast six chaparral removal or “fuels manipulation” treatments: (1) fall fire, (2) winter fire, (3) spring fire, (4) fall mastication, (5) spring mastication and (6) untreated control. Treatments and controls were implemented in plots 2 ha or larger, and replicated four times each.

We find that species richness in prescribed fire treatments reaches comparable levels to controls in the first 3 years following treatment, whereas masticated units always have lower species richness. Generalized linear mixed models additionally confirm that mastication has highly negative effects on observed abundances of birds compared to controls and to prescribed fire.

The season in which fuels reduction occurred was less important to species richness, although fall fire was more beneficial to bird abundance than spring or winter fire. Fire treatments in all seasons maintain the same general bird community structure as controls, while mastication results in strongly differentiated assemblages, increasing granivores while nearly excluding foliage gleaners.

Synthesis and applications. We compare two California chaparral management techniques, prescribed fire and mastication, in three seasons (fall, winter and spring) in northern California, USA. We tracked chaparral bird community response in 23 experimental units for 2–5 years. We conclude that prescribed fire and mastication are not interchangeable management techniques, and that mastication negatively impacts bird communities, altering guild structure and reducing both diversity and abundance.
Energy drives the dynamic localization of cyanobacterial nitrogen regulators during diurnal cycles
Authors: Espinosa Javier , Labella José I. , Cantos Raquel , Contreras Asunción
Published: February 2018

Cyanobacteria, phototrophic organisms performing oxygenic photosynthesis, must adapt their metabolic processes to the challenges imposed by the succession of days and nights. Two conserved cyanobacterial proteins, PII and PipX, function as hubs of the nitrogen interaction network, forming complexes with a variety of diverse targets. While PII proteins are found in all three domains of life as integrators of signals of the nitrogen and carbon balance, PipX proteins are unique to cyanobacteria, where they provide a mechanistic link between PII signalling and the control of gene expression by the global nitrogen regulator NtcA. Here we demonstrate that PII and PipX display distinct localization patterns during diurnal cycles, co‐localizing into the same foci at the periphery and poles of the cells during dark periods, a circadian‐independent process requiring a low ATP/ADP ratio. Genetic, cellular biology and biochemical approaches used here provide new insights into the nitrogen regulatory network, calling attention to the roles of PII as energy sensors and its interactions with PipX in the context of essential signalling pathways. This study expands the contribution of the nitrogen regulators PII and PipX to integrate and transduce key environmental signals that allow cyanobacteria to thrive in our planet.