bluuebunny/crossref_metadata_2025 huggingface dataset:
Scattering Calculations for Asymmetric Raindrops during a Line Convection Event: Comparison with Radar Measurements
Authors: Manić Sanja B. , Thurai Merhala , Bringi V. N. , Notaroš Branislav M.
Published: April 2018

Two-dimensional video disdrometer (2DVD) data from a line convection rain event are analyzed using the method of moments surface integral equation (MoM-SIE) via drop-by-drop polarimetric scattering calculations at C band that are compared with radar measurements. Drop geometry of asymmetric drop shapes is reconstructed from 2DVD measurements, and the MoM-SIE model is created by meshing the surface of the drop. The differential reflectivity Zdr calculations for an example asymmetric drop are validated against an industry standard code solution at C band, and the azimuthal dependence of results is documented. Using the MoM-SIE analysis on 2DVD drop-by-drop data (also referred to as simply MoM-SIE), the radar variables [Zh, Zdr, Kdp, ρhv] are computed as a function of time (with 1-min resolution) and compared to C-band radar measurements. The importance of shape variability of asymmetric drops is demonstrated by comparing with the traditional (or “bulk”) method, which uses 1-min averaged drop size distributions and equilibrium oblate shapes. This was especially pronounced for ρhv, where the MoM-SIE method showed lowered values (dip) during the passage of the line convection consistent with radar measurements, unlike the bulk method. The MoM-SIE calculations of [Zh, Zdr, Kdp] agree very well with the radar measurements, whereas linear depolarization ratio (LDR) calculations from the drop-by-drop method are found to be larger than the values from the bulk method, which is consistent with the dip in simulated and radar-measured ρhv. Our calculations show the importance of the variance of shapes resulting from asymmetric drops in the calculation of ρhv and LDR.
From a Sampling Precision Perspective, Skewness Is a Friend and Not an Enemy!
Authors: Trafimow David , Wang Tonghui , Wang Cong
Published: April 2018

Two recent publications in Educational and Psychological Measurement advocated that researchers consider using the a priori procedure. According to this procedure, the researcher specifies, prior to data collection, how close she wishes her sample mean(s) to be to the corresponding population mean(s), and the desired probability of being that close. A priori equations provide the necessary sample size to meet specifications under the normal distribution. Or, if sample size is taken as given, a priori equations provide the precision with which estimates of distribution means can be made. However, there is currently no way to perform these calculations under the more general family of skew-normal distributions. The present research provides the necessary equations. In addition, we show how skewness can increase the precision with which locations of distributions can be estimated. This conclusion, based on the perspective of improving sampling precision, contrasts with a typical argument in favor of performing transformations to normalize skewed data for the sake of performing more efficient significance tests.
Information-Pooling Bias in Collaborative Security Incident Correlation Analysis
Authors: Rajivan Prashanth , Cooke Nancy J.
Published: April 2018

Objective:

Incident correlation is a vital step in the cybersecurity threat detection process. This article presents research on the effect of group-level information-pooling bias on collaborative incident correlation analysis in a synthetic task environment.

Background:

Past research has shown that uneven information distribution biases people to share information that is known to most team members and prevents them from sharing any unique information available with them. The effect of such biases on security team collaborations are largely unknown.

Method:

Thirty 3-person teams performed two threat detection missions involving information sharing and correlating security incidents. Incidents were predistributed to each person in the team based on the hidden profile paradigm. Participant teams, randomly assigned to three experimental groups, used different collaboration aids during Mission 2.

Results:

Communication analysis revealed that participant teams were 3 times more likely to discuss security incidents commonly known to the majority. Unaided team collaboration was inefficient in finding associations between security incidents uniquely available to each member of the team. Visualizations that augment perceptual processing and recognition memory were found to mitigate the bias.

Conclusion:

The data suggest that (a) security analyst teams, when conducting collaborative correlation analysis, could be inefficient in pooling unique information from their peers; (b) employing off-the-shelf collaboration tools in cybersecurity defense environments is inadequate; and (c) collaborative security visualization tools developed considering the human cognitive limitations of security analysts is necessary.

Application:

Potential applications of this research include development of team training procedures and collaboration tool development for security analysts.
PD‐1 Inhibition Minimally Affects Cisplatin‐Induced Toxicities in a Murine Model
Authors: Spielbauer Katie , Cunningham Lisa , Schmitt Nicole
Published: April 2018

Immune checkpoint inhibition used in combination with standard cisplatin‐based chemotherapy regimens is currently under evaluation in clinical trials for head and neck squamous cell carcinoma (HNSCC). The impact of anti–PD‐1 therapy on cisplatin‐induced ototoxicity and nephrotoxicity has not been established. Here we use a murine model of cisplatin‐induced hearing loss to investigate the impact of anti–PD‐1 immunotherapy on auditory brainstem responses (ABRs), distortion product otoacoustic emissions (DPOAEs), serum creatinine, and hair cell and renal histology. We demonstrate only mild worsening of DPOAEs at 14.4 and 16 kHz as well as a mild increase in serum creatinine. Renal and hair cell histology as well as ABR measures were unchanged by PD‐1 inhibition. Thus, our data suggest that the use of PD‐1 inhibition in conjunction with cisplatin results in toxicities that are similar to those of cisplatin alone.
Laryngeal Force Sensor: Quantifying Extralaryngeal Complications after Suspension Microlaryngoscopy
Authors: Feng Allen L. , Song Phillip C.
Published: April 2018

Objectives

To develop a novel sensor capable of dynamically analyzing the force exerted during suspension microlaryngoscopy and to examine the relationship between force and postoperative tongue complications.

Study Design

Prospective observational study.

Setting

Academic tertiary care center.

Methods

The laryngeal force sensor is a designed for use during microphonosurgery. Prospectively enrolled patients completed pre‐ and postoperative surveys to assess the development of tongue‐related symptoms (dysgeusia, pain, paresthesia, and paresis) or dysphagia (10‐item Eating Assessment Tool [EAT‐10]). To prevent operator bias, surgeons were blinded to the force recordings during surgery.

Results

Fifty‐six patients completed the study. Of these, 20 (36%) developed postoperative tongue symptoms, and 12 (21%) had abnormal EAT‐10 scores. The mean maximum force across all procedures was 164.7 N (95% CI, 141.0‐188.4; range, 48.5‐402.6), while the mean suspension time was 34.3 minutes (95% CI, 27.4‐41.2; range, 7.1‐108.1). Multiple logistic regression showed maximum force (odds ratio, 1.15; 95% CI, 1.02‐1.29; P =. 019) and female sex (30.1%; 95% CI, 22.7%‐37.5%; P <. 001) as significant predictors for the development of tongue‐related symptoms. The only significant predictor of an abnormal postoperative EAT‐10 score was an increased maximum force (odds ratio, 1.03; 95% CI, 1.00‐1.06; P =. 045).

Conclusions

The laryngeal force sensor is capable of providing dynamic force measurements throughout suspension microlaryngoscopy. An increase in maximum force during surgery may be a significant predictor for the development of tongue‐related symptoms and an abnormal EAT‐10 score. Female patients may also be at greater risk for developing postoperative tongue symptoms.
Trends in Pediatric Otolaryngology Disparities Research
Authors: Jabbour Jad , Doerfer Karl W. , Robey Thomas , Cunningham Michael J.
Published: April 2018

Objectives

To describe trends in disparities research within pediatric otolaryngology as evidenced by major meeting presentations and to compare observed trends with those in the realm of patient safety and quality improvement (PSQI).

Study Design

Retrospective review of presentations at national otolaryngology meetings.

Setting

Online review of meeting programs.

Subjects and Methods

Meeting programs from the American Society of Pediatric Otolaryngology, Triological Society, American Academy of Otolaryngology—Head and Neck Surgery Foundation, and Society for Ear, Nose and Throat Advances in Children from 2003 to 2016 were manually searched for pediatric oral and poster presentations addressing disparities and socioeconomic determinants of health, as well as PSQI. Presentation frequency was compared between categories and within each category over time.

Results

Of 11,311 total presentations, 3078 were related to the pediatric population, and 1945 (63.2%) of those were oral presentations. Disparities‐related presentations increased from 0 in 2003 to 17 in 2016. From 2003 to 2009, 9 of 656 (1.4%) presentations involved disparities, as opposed to 70 of 2422 (2.9%) from 2010 to 2016 (P =. 03). The proportion of presentations regarding PSQI also increased: from 42 of 656 (6.4%) in 2003‐2009 to 221 of 2422 (9.1%) in 2010‐2016 (P =. 01). PSQI presentations remain more common than disparities presentations (9.1% vs 2.9%, P <. 001).

Conclusion

Health care disparities are increasingly addressed in pediatric otolaryngology meeting presentations. Compared with the well‐established realm of PSQI, disparities research remains nascent but is gaining attention. Health care reform and quality improvement efforts should recognize the role of socioeconomic factors and include strategies for addressing disparities.
Juvenile cerebral ischemia reveals age-dependent BDNF–TrkB signaling changes: Novel mechanism of recovery and therapeutic intervention
Authors: Dietz Robert M , Orfila James E , Rodgers Krista M , Patsos Olivia P , Deng Guiying , Chalmers Nicholas , Quillinan Nidia , Traystman Richard J , Herson Paco S
Published: April 2018

Global ischemia in childhood often leads to poor neurologic outcomes, including learning and memory deficits. Using our novel model of childhood cardiac arrest/cardiopulmonary resuscitation (CA/CPR), we investigate the mechanism of ischemia-induced cognitive deficits and recovery. Memory is impaired seven days after juvenile CA/CPR and completely recovers by 30 days. Consistent with this remarkable recovery not observed in adults, hippocampal long-term potentiation (LTP) is impaired 7–14 days after CA/CPR, recovering by 30 days. This recovery is not due to the replacement of dead neurons (neurogenesis), but rather correlates with brain-derived neurotrophic factor (BDNF) expression, implicating BDNF as the molecular mechanism underlying impairment and recovery. Importantly, delayed activation of TrkB receptor signaling reverses CA/CPR-induced LTP deficits and memory impairments. These data provide two new insights (1) endogenous recovery of memory and LTP through development may contribute to improved neurological outcome in children compared to adults and (2) BDNF-enhancing drugs speed recovery from pediatric cardiac arrest during the critical school ages.
Predictors of Death Penalty Views in China: An Empirical Comparison Between College Students and Citizens
Authors: Jiang Shanhe , Hu Ming , Lambert Eric G.
Published: April 2018

China’s current Criminal Law has 46 death-eligible offenses, and China executes more people than any other country in the world. However, there is a lack of study of attitudes toward capital punishment for specific offenses, and no death penalty view comparison between college students and regular citizens in China was found. This study was taken to address these limitations. Using a sample of 401 respondents from Zhejiang, China, in 2016, the present study found that more than 72% of respondents favored the death penalty without any specification of crime types. Level of death penalty support differed by various specific crimes. As expected, relative to college students, general population citizens were more likely to support capital punishment. Both groups had the highest death penalty support for murder. The study also revealed similar and different reasons behind death penalty attitudes between college students and regular citizens.
Use of an Artificial Neural Network Approach for the Prediction of Resilient Modulus for Unbound Granular Material
Authors: Saha Sajib , Gu Fan , Luo Xue , Lytton Robert L.
Published: April 2018

The resilient modulus ( MR) is a fundamental material property that has a direct effect on the design and analysis of pavement structures. Many regression models have been developed previously to predict the coefficients of the MR model from physical properties of base materials. However, the predicted model coefficients are confined to either a limited number of base materials or result in poor accuracy. To overcome this issue, a moisture- and stress-dependent model is adopted in this study to precisely estimate MR of unbound base materials in unsaturated conditions, and a set of artificial neural network (ANN) models is developed to predict the coefficients of this model from base physical properties. The developed ANN models consist of seven input variables, ten hidden neurons, and one output variable. A large unbound base dataset was collected from the Long Term Pavement Performance (LTPP) database and used to train and generalize the network. Soil physical properties such as gradation (percent passing No. 3/8 sieve, percent passing No. 200 sieve), gradation shape parameter and scale parameter, index properties (i.e., plastic limit and plasticity index), maximum dry density, optimum moisture content, and test moisture content were selected as inputs for the ANN model. The MR values estimated using the predicted coefficients were compared with the experimental data collected from LTPP and showed an R2 value above 0.9, which is much higher than the MR values computed using regression models. Finally, the MR test results from different sources were used to validate the developed ANN models.
Visual outcomes of pediatric traumatic cataracts
Authors: Jinagal Jitender , Gupta Gaurav , Gupta Parul C , Yangzes Sonam , Singh Rishiraj , Gupta Rohit , Ram Jagat
Published: April 2018

Introduction:

To report visual outcomes and risk factors of pediatric traumatic cataracts in a tertiary care referral center in northern India.

Methods:

We analyzed medical records of traumatic cataracts in the pediatric age group (1–15 years) operated for cataract surgery with or without posterior chamber intraocular lens implantation with or without primary posterior capsulotomy with anterior vitrectomy between 2004 and 2012. Causative agents, types of trauma, demographic factors, surgical interventions, complications, and visual acuity were recorded and compared among different groups.

Results:

A total of 147 children were documented to have undergone cataract surgery for traumatic cataract in the study period, male-to-female ratio being approximately 5:1. Mean age was 7.67 ± 3.30 years (range, 1–15 years). Type of primary insult was penetrating injury in 100 (68%) patients and blunt trauma in 47 (32%) patients. Mean interval between injury and cataract surgery in penetrating injury cases was 3.84 ± 7.05 months and in the blunt injury cases was 6.28 ± 11.13 months. Preoperatively, only 110 patients were cooperative for visual acuity. Out of them, none had vision better than 6/18 and only 21 patients (19.9%) had vision of ≥6/60. Visual acuity of 6/18 or better (was considered good visual outcome) was achieved by 87.9%, 97.3%, and 97.9% at 1, 6, and 36 months, postoperatively. Eyes which underwent primary posterior capsulotomy and anterior vitrectomy during cataract surgery showed statistically better visual outcome than those without it.

Conclusion:

Phacoaspiration with posterior chamber intraocular lens implantation along with primary posterior capsulotomy and anterior vitrectomy and timely introduction of amblyopia therapy helped in gaining good visual outcome in pediatric traumatic cataract patients irrespective of the age of presentation and the type of injury.
Accommodating Grief on Twitter: An Analysis of Expressions of Grief Among Gang Involved Youth on Twitter Using Qualitative Analysis and Natural Language Processing
Authors: Patton Desmond Upton , MacBeth Jamie , Schoenebeck Sarita , Shear Katherine , McKeown Kathleen
Published: April 2018

There is a dearth of research investigating youths’ experience of grief and mourning after the death of close friends or family. Even less research has explored the question of how youth use social media sites to engage in the grieving process. This study employs qualitative analysis and natural language processing to examine tweets that follow 2 deaths. First, we conducted a close textual read on a sample of tweets by Gakirah Barnes, a gang-involved teenaged girl in Chicago, and members of her Twitter network, over a 19-day period in 2014 during which 2 significant deaths occurred: that of Raason “Lil B” Shaw and Gakirah’s own death. We leverage the grief literature to understand the way Gakirah and her peers express thoughts, feelings, and behaviors at the time of these deaths. We also present and explain the rich and complex style of online communication among gang-involved youth, one that has been overlooked in prior research. Next, we overview the natural language processing output for expressions of loss and grief in our data set based on qualitative findings and present an error analysis on its output for grief. We conclude with a call for interdisciplinary research that analyzes online and offline behaviors to help understand physical and emotional violence and other problematic behaviors prevalent among marginalized communities.
The Prevalence of Hypovitaminosis D and Its Associated Risk Factors Among Women of Reproductive Age in Saudi Arabia: A Systematic Review and Meta-Analysis
Authors: Alzaheb Riyadh A
Published: April 2018

Vitamin D deficiency is currently a worldwide epidemic. Middle Eastern countries, including Saudi Arabia, have high vitamin D deficiency prevalence, most prominently among women, despite their plentiful year-round sunshine. Previous research investigating vitamin D status among Saudi women of reproductive age (15-49 years) is scarce, and no study has used a nationally representative sample, so this review quantified overall hypovitaminosis D prevalence among women in Saudi Arabia and explored the associated risk factors. The Web of Science, Scopus, and Medline databases were searched for prior studies in Saudi Arabia exploring vitamin D status among women of reproductive age, published between January 1, 2000 and May 25, 2017. Data were extracted from the identified studies, and a random effects model meta-analysis established the overall hypovitaminosis D prevalence. The initial search yielded 223 possibly relevant articles; 13 were confirmed as eligible, with samples totaling 2877 women aged between 15 and 49 years. Meta-analysis revealed a mean serum 25-hydroxyvitamin D, 25(OH)D, level of 13.1 ng/mL (95% confidence interval [CI]: 11.6-14.6) and an overall prevalence of hypovitaminosis D, defined as 25(OH)D < 30 ng/mL, of 77.4% (95% CI: 63.2-87.3), mostly due to insufficient sunlight exposure and low dietary vitamin D intake. There is therefore a need for a national strategy to raise vitamin D levels among women in Saudi Arabia by advising them on natural vitamin D sources, and recommending the timing and duration of sun exposure, while also defining a national approach to vitamin D fortification and supplementation.
The Faculty of Intensive Care Medicine Workforce Survey – What impacts on our working lives?
Authors: Grailey KE , Bryden DC , Brett SJ
Published: April 2018

The Faculty of Intensive Care Medicine distributes an annual survey to its Consultants, allowing the evaluation of workforce profile, working patterns and the opportunity for analysis of key information on issues affecting these. We undertook an exploratory review of the data provided within the 2016 survey, with the aim of identifying themes within respondents stated career intentions and associated factors. Given the modest (36%) response rate, we are unable to draw conclusions with certainty, but there are indications within the data that the UK Intensive Care Medicine consultant body is facing significant stressors whilst at work, due to working patterns and limited resources. The data within the 2016 survey provide a base from which to develop future Faculty of Intensive Care Medicine workforce surveys that will extract data about the positive aspects of a career in intensive care medicine. The survey data provide a signal that there may be significant potentially modifiable stressors for intensive care doctors, and as such affords support for initiatives to improve job planning and sharing of implemented solutions, as well as a need to focus on workforce wellbeing as an important and necessary contributor to patient safety within intensive care medicine.
Diagnostic Accuracy Of The Electrocardiographic Decision Support – Myocardial Ischaemia (EDS-MI) Algorithm In Detection Of Acute Coronary Occlusion
Authors: Lindow Thomas , Pahlm Olle , Olson Charles W , Khoshnood Ardavan , Ekelund Ulf , Carlsson Marcus , Swenne Cees A , Man Sumche , Engblom Henrik
Published: April 2018

Electrocardiographic Decision Support – Myocardial Ischaemia (EDS-MI) is a graphical decision support for detection and localization of acute transmural ischaemia. A recent study indicated that EDS-MI performs well for detection of acute transmural ischaemia. However, its performance has not been tested in patients with non-ischaemic ST-deviation. We aimed to optimize the diagnostic accuracy of EDS-MI in patients with verified acute coronary occlusion as well as patients with non-ischaemic ST deviation and compare its performance with STEMI criteria. We studied 135 patients with non-ischaemic ST deviation (perimyocarditis, left ventricular hypertrophy, takotsubo cardiomyopathy and early repolarization) and 117 patients with acute coronary occlusion. In 63 ischaemic patients, the extent and location of the ischaemic area (myocardium at risk) was assessed by both cardiovascular magnetic resonance imaging and EDS-MI. Sensitivity and specificity of ST elevation myocardial infarction criteria were 85% (95% confidence interval (CI) 77, 90) and 44% (95% CI 36, 53) respectively. Using EDS-MI, sensitivity and specificity increased to 92% (95% CI 85, 95) and 81% (95% CI 74, 87) respectively (p=0.035 and p<0.001). Agreement was strong (83%) between cardiovascular magnetic resonance imaging and EDS-MI in localization of ischaemia. Mean myocardium at risk was 32% (± 10) by cardiovascular magnetic resonance imaging and 33% (± 11) by EDS-MI when the estimated infarcted area according to Selvester QRS scoring was included in myocardium at risk estimation. In conclusion, EDS-MI increases diagnostic accuracy and may serve as an automatic decision support in the early management of patients with suspected acute coronary syndrome. The added clinical benefit in a non-selected clinical chest pain population needs to be assessed.
Impact of known or new-onset atrial fibrillation on 2-year cardiovascular event rate in patients with acute coronary syndromes: results from the prospective EPICOR Registry
Authors: Zeymer Uwe , Annemans Lieven , Danchin Nicolas , Pocock Stuart , Newsome Simon , Van de Werf Frans , Medina Jesús , Bueno Héctor
Published: April 2018

Background:

Atrial fibrillation (AF) is associated with increased morbidity in acute coronary syndrome patients, but impact on outcomes beyond 1 year is unclear.

Methods:

This was a post-hoc analysis from the long-tErm follow-uP of antithrombotic management patterns In acute CORonary syndrome patients (EPICOR) registry (NCT01171404), a prospective, observational study conducted in Europe and Latin America, which enrolled acute coronary syndrome survivors at discharge. Antithrombotic management patterns, mortality, a composite endpoint of death/new non-fatal myocardial infarction/stroke and bleeding events were assessed after 2 years of follow-up in patients with or without AF.

Results:

Of 10,568 patients enrolled, 397 (4.7%) had prior AF and 382 (3.6%) new-onset AF during index hospitalisation. Fewer patients with AF underwent percutaneous coronary intervention (52.1% vs. 66.6%; P<0.0001). At discharge, fewer AF patients received dual antiplatelet therapy (71.6% vs. 89.5%; P<0.0001); oral anticoagulant use was higher in AF patients but was still infrequent (35.0% vs. 2.5%; P<0.0001). Use of dual antiplatelet therapy and oral anticoagulants declined over follow-up with over 50% of all AF/no AF patients remaining on dual antiplatelet therapy (55.6% vs. 60.6%), and 23.3% (new-onset AF) to 42.1% (prior AF) on oral anticoagulants at 2 years. At 2 years, mortality, composite endpoint and bleeding rates were higher in AF patients (all P<0.0001) compared to patients without AF. On multivariable analysis, the risk of mortality or the composite endpoint was significant for prior AF ( P=0.003, P=0.001) but not new-onset AF ( P=0.88, P=0.92).

Conclusions:

Acute coronary syndrome patients with AF represent a high-risk group with increased event rates during long-term follow-up. Prior AF is an independent predictor of mortality and/or ischaemic events at 2 years. Use of anticoagulants in AF after acute coronary syndrome is still suboptimal.
Contradictions of Conservatism
Authors: Kaviraj Sudipta
Published: April 2018

This article identifies the difficulty in defining conservatism and then goes on to illustrate the contradiction inherent in conservative thought.* The central problem addressed by the article is the absence of conservative thinking in modern India. Contrary to the practice of labelling certain strands of thinking as conservative, Indian political thought of past two centuries hardly has any serious conservative tradition. Looking at the ideas of Malaviya, Gandhi and Hindu nationalists, this article shows that while some of their positions did come close to conservative thinking, they did not systematically pursue conservative thinking. A key reason for this is the colonial rupture that negative possibility of serious engagement with past.
Not Just for Customers Anymore: Organization Facebook, Employee Social Capital, and Organizational Identification
Authors: Sias Patricia M. , Duncan Kaylin L.
Published: April 2018

This study examined links between employee interaction with their organization’s official Facebook page, social capital, and employee identification with the organization. Results indicate employee interaction with their company’s Facebook page was positively related to organizational identification and bridging and bonding social capital. Moreover, the relationship between interaction with the company Facebook page and identification was partially mediated by bridging social capital outcomes. Overall, results suggest the company Facebook page is an important communicative bridge between the employee and the larger organization, enhancing the employee-organization relationship. Results contribute to our understanding of social media and organizational identification, as well as our understanding of social capital associated with social media use in organizational settings.
Historical Shadows: The Links between Sundown Towns and Contemporary Black–White Inequality
Authors: O’Connell Heather A.
Published: April 2018

I contribute to our understanding of black–white inequality in the United States by assessing the legacy of “sundown towns.” Sundown towns are places that restricted who could live there based on ideas about race. The often-violent tactics employed to create and maintain all-white spaces reshaped dramatically the demographic and social landscape of the non-South. I extend previous research on sundown towns by examining their association with contemporary black–white economic inequality. In addition, I advance a new theoretical perspective to explain how the history associated with sundown towns contributes to contemporary inequality, namely large-scale segregation. To assess the contemporary impact of sundown history, I employ a dataset on places connected to sundown towns in the eastern Midwest and county data from the 2008–2012 American Community Survey (ACS) period estimates. In addition, I use standard ordinary least squares (OLS) and spatial data analysis techniques to provide a multifaceted assessment of the contribution of sundown towns to contemporary black–white inequality. This analysis extends our understanding of the social impact of historical legacies and emphasizes the importance of the protection of white advantage and large-scale segregation when explaining the (re)production of black–white inequality in the United States.
Survival of OPEC and Saudi–Iran Relations—A Historical Overview
Authors: Elyassi Hamid
Published: April 2018

In their attempt to stay the tide of falling oil prices, in November 2016, the Organization of Petroleum Exporting Countries (OPEC) producers decided to cut back output with some members, notably Iran, being exempted from the scheme. The collective decision had the approval of Saudi Arabia at a time when its decades-old rivalry with Iran was escalating into bloody proxy wars, at least partly financed by the two governments’ oil revenues. As such, the hostility between the two countries had cast doubt on OPEC’s power of effective intervention in the oil market and even its very survival. Yet, not for the first time in its history, the organization escaped the fate of many similar associations of states which have fallen victim to internal political squabbles. What has been the secret of the survival of this particular entity and what lessons it may have for preserving existing international associations of nations? This article discusses these questions in the light of the history of OPEC and relations between Saudi Arabia and Iran as rival regional powers and founding members of the organization.
Late neuroprogenitors contribute to normal retinal vascular development in a Hif2a-dependent manner
Authors: Cristante Enrico , Liyanage Sidath E. , Sampson Robert D. , Kalargyrou Aikaterini , De Rossi Giulia , Rizzi Matteo , Hoke Justin , Ribeiro Joana , Maswood Ryea N. , Duran Yanai , Matsuki Takaaki , Aghaizu Nozie D. , Luhmann Ulrich F. , Smith Alexander J. , Ali Robin R. , Bainbridge James W. B.
Published: April 2018

In the adult central nervous system, endothelial and neuronal cells engage in tight cross-talk as key components of the so-called neurovascular unit. Impairment of this important relationship adversely affects tissue homeostasis, as observed in neurodegenerative conditions including Alzheimer's and Parkinson's disease. In development, the influence of neuroprogenitor cells on angiogenesis is poorly understood. Here, we show in mouse that these cells interact intimately with the growing retinal vascular network, and we identify a novel regulatory mechanism of vasculature development mediated by hypoxia-inducible factor 2a (Hif2a). By Cre-lox gene excision, we show that Hif2a in retinal neuroprogenitor cells upregulates the expression of the pro-angiogenic mediators vascular endothelial growth factor and erythropoietin, whereas it locally downregulates the angiogenesis inhibitor endostatin. Importantly, absence of Hif2a in retinal neuroprogenitor cells causes a marked reduction of proliferating endothelial cells at the angiogenic front. This results in delayed retinal vascular development, fewer major retinal vessels and reduced density of the peripheral deep retinal vascular plexus. Our findings demonstrate that retinal neuroprogenitor cells are a crucial component of the developing neurovascular unit.
Heterogeneous fates and dynamic rearrangement of regenerative epidermis-derived cells during zebrafish fin regeneration
Authors: Shibata Eri , Ando Kazunori , Murase Emiko , Kawakami Atsushi
Published: April 2018

The regenerative epidermis (RE) is a specialized tissue that plays an essential role in tissue regeneration. However, the fate of the RE during and after regeneration is unknown. In this study, we performed Cre-loxP-mediated cell fate tracking and revealed the fates of a major population of the RE cells that express fibronectin 1b (fn1b) during zebrafish fin regeneration. Our study showed that these RE cells are mainly recruited from the inter-ray epidermis, and that they follow heterogeneous cell fates. Early recruited cells contribute to initial wound healing and soon disappear by apoptosis, while the later recruited cells contribute to the regenerated epidermis. Intriguingly, many of these cells are also expelled from the regenerated tissue by a dynamic caudal movement of the epidermis over time, and in turn the loss of epidermal cells is replenished by a global self-replication of basal and suprabasal cells in fin. De-differentiation of non-basal epidermal cells into the basal epidermal cells did not occur during regeneration. Overall, our study reveals the heterogeneous fates of RE cells and a dynamic rearrangement of the epidermis during and after regeneration.
Coordinated directional outgrowth and pattern formation by integration of Wnt5a and Fgf signaling in planar cell polarity
Authors: Gao Bo , Ajima Rieko , Yang Wei , Li Chunyu , Song Hai , Anderson Matthew J. , Liu Robert R. , Lewandoski Mark B. , Yamaguchi Terry P. , Yang Yingzi
Published: April 2018

Embryonic morphogenesis of a complex organism requires proper regulation of patterning and directional growth. Planar cell polarity (PCP) signaling is emerging as a crucial evolutionarily conserved mechanism whereby directional information is conveyed. PCP is thought to be established by global cues, and recent studies have revealed an instructive role of a Wnt signaling gradient in epithelial tissues of both invertebrates and vertebrates. However, it remains unclear whether Wnt/PCP signaling is regulated in a coordinated manner with embryonic patterning during morphogenesis. Here, in mouse developing limbs, we find that apical ectoderm ridge-derived Fgfs required for limb patterning regulate PCP along the proximal-distal axis in a Wnt5a-dependent manner. We demonstrate with genetic evidence that the Wnt5a gradient acts as a global cue that is instructive in establishing PCP in the limb mesenchyme, and that Wnt5a also plays a permissive role to allow Fgf signaling to orient PCP. Our results indicate that limb morphogenesis is regulated by coordination of directional growth and patterning through integration of Wnt5a and Fgf signaling.
Independent and combined effects of egg pro- and anti-oxidants on gull chick phenotype
Authors: Possenti Cristina Daniela , Secomandi Simona , Schiavon Alfredo , Caprioli Manuela , Rubolini Diego , Romano Andrea , Saino Nicola , Parolini Marco
Published: April 2018

Oviparous mothers transfer to the eggs components that have both independent and combined effects on offspring phenotype. Functional interactions between egg components, such as antioxidant and hormones, lead to expect that a change in the concentration of one component has effects on offspring traits that depend on the concentration of other interacting components. However, the combined effects of variation in different egg components are virtually unknown. Bird eggs contain vitamin E, a major antioxidant, and also maternal corticosterone. The independent consequences of variation in the egg concentrations of these compounds for offspring phenotype are largely unknown and no study has investigated their combined effects. We manipulated the concentration of vitamin E and corticosterone in the eggs of the yellow-legged gull (Larus michahellis) by administering a physiological (2 standard deviations) dose both independently and in combination. We tested for an effect on chick post-natal growth, plasma antioxidant capacity (TAC) and oxidative compounds (TOS). Separate administration of vitamin E or corticosterone caused a reduction in body mass relative to controls, whereas the combined administration of the two compounds reversed their negative effects. These results suggest that maternal egg components, such as antioxidants and steroid hormones, interact and mothers must balance their concentrations in order to achieve optimal offspring phenotype. The functional relationship between vitamin E and corticosterone is corroborated by the observation of positive covariation between these compounds.
Continuous Glucose Monitoring at High Altitude—Effects on Glucose Homeostasis
Authors: HILL NEIL E. , DEIGHTON KEVIN , MATU JAMIE , MISRA SHIVANI , OLIVER NICK S. , NEWMAN CARRIE , MELLOR ADRIAN , O’HARA JOHN , WOODS DAVID
Published: April 2018

Purpose

Exposure to high altitude has been shown to enhance both glucose and lipid utilization depending on experimental protocol. In addition, high and low blood glucose levels have been reported at high altitude. We hypothesized that gradual ascent to high altitude results in changes in glucose levels in healthy young adults.

Methods

Twenty-five adult volunteers, split into two teams, took part in the British Services Dhaulagiri Medical Research Expedition completing 14 d of trekking around the Dhaulagiri circuit in Nepal reaching a peak altitude of 5300 m on day 11 of the trek. Participants wore blinded continuous glucose monitors (CGM) throughout. Blood samples for C-peptide, proinsulin, and triacylglycerides were taken at sea level (United Kingdom) and in acclimatization camps at 3600, 4650, and 5120 m. Energy intake was determined from food diaries.

Results

There was no difference in time spent in hypoglycemia stratified by altitude. Nocturnal CGM readings (2200–0600 h) were chosen to reduce the short-term effect of physical activity and food intake and showed a significant (P < 0.0001) increase at 3600 m (5.53 ± 0.22 mmol·L−1), 4650 m (4.77 ± 0.30 mmol·L−1), and 5120 m (4.78 ± 0.24 mmol·L−1) compared with baseline altitude 1100 m (vs 4.61 ± 0.25 mmol·L−1). Energy intake did not differ by altitude. Insulin resistance and beta-cell function, calculated by homeostatic model assessment, were reduced at 3600 m compared with sea level.

Conclusions

We observed a significant increase in nocturnal CGM glucose at 3600 m and greater despite gradual ascent from 1100 m. Taken with the changes in insulin resistance and beta-cell function, it is possible that the stress response to high altitude dominates exercise-enhanced insulin sensitivity, resulting in relative hyperglycemia.
Neuromuscular Dysfunction and Cortical Impairment in Sleep Apnea Syndrome
Authors: MARILLIER MATHIEU , GRUET MATHIEU , BAILLIEUL SÉBASTIEN , LE ROUX MALLOUF THIBAULT , WUYAM BERNARD , TAMISIER RENAUD , LEVY PATRICK , PEPIN JEAN-LOUIS , VERGES SAMUEL
Published: April 2018

Purpose

Lower muscle strength and endurance have been reported in severe obstructive sleep apnea (OSA). Increased intracortical inhibition previously reported at rest in OSA suggests central neuromuscular impairments in these patients. We hypothesized that (i) OSA patients demonstrate reduced knee extensor strength and endurance due to central impairments and (ii) continuous positive airway pressure (CPAP) treatment improves neuromuscular function in these patients.

Methods

Twelve OSA patients and 11 healthy controls performed intermittent knee extensions until task failure before and after 8 wk of CPAP treatment or control period. Maximal voluntary contraction, voluntary activation and corticospinal excitability and inhibition assessed by single- and paired-pulse transcranial magnetic stimulation were measured before and during the fatiguing task.

Results

Time to exhaustion was lower in OSA (before CPAP treatment: 1008 ± 549 s; after CPAP treatment: 975 ± 378 s) compared with controls (before control period: 1476 ± 633 s; after control period: 1274 ± 506 s; P = 0.017). Obstructive sleep apnea patients had reduced maximal voluntary contraction and VATMS compared with controls throughout the fatiguing task as well as increased intracortical inhibition (all P < 0.05). Continuous positive airway pressure treatment did not induce any changes in neuromuscular function (P > 0.05 for all parameters).

Conclusions

This study demonstrates that severe OSA patients have cortical impairments which are likely contributing to their reduced knee extensors strength and endurance. Both cortical impairments and neuromuscular function are not improved after 8 wk of CPAP treatment.
Biomechanical Model for Stress Fracture–related Factors in Athletes and Soldiers
Authors: HADID AMIR , EPSTEIN YORAM , SHABSHIN NOGAH , GEFEN AMIT
Published: April 2018

Stress fractures (SF) are one of the most common and potentially serious overuse injuries.

Purpose

This study aimed to develop a computational biomechanical model of strain in human tibial bone that will facilitate better understanding of the pathophysiology of SF.

Methods

The MRI of a healthy, young male was used for full anatomical segmentation of the calf tissues, which considered hard–soft tissues biomechanical interactions. From the undeformed coronal MR images, the geometry of bones, muscles, connecting ligaments, and fat were reconstructed in three dimensions and meshed to a finite element model. A force that simulated walking was applied on the tibial plateaus. The model was then analyzed for strains in the tibia under various conditions: unloaded walking, walking with a load equivalent to 30% of bodyweight, and walking under conditions of muscular fatigue. In addition, the effect of tibia robustness on strain was analyzed.

Results

The model showed that the tibia is mostly loaded by compression, with maximal strains detected in the distal anterior surface: 1241 and 384 microstrain, compressive and tensile, respectively. Load carriage resulted in ~30% increase in maximal effective strains. Muscle fatigue has a complex effect; fatigued calf muscles (soleus) reduced the maximal effective strains up to 9%, but fatigued thigh muscles increased those strains by up to 3%. It had also been shown that a slender tibia is substantially prone to higher maximal effective strains compared with an average (22% higher) or robust tibia (39% higher).

Conclusions

Thigh muscle fatigue, load carriage, and a slender tibia were detected as factors that may contribute to the development of SF. The methodology presented here is a novel tool for investigating the pathophysiology of SF.
A crise do trânsito em São Paulo e seus custos
Authors: Cintra Marcos
Published: April 2018

É tempo de repensar o modelo viário paulistano. Em face do crescimento do número de automóveis e congestionamentos nas principais vias arteriais da metrópole, investimentos em infraestrutura tornam-se indispensáveis para melhorar a circulação do trânsito.
Inclusão financeira e correspondentes bancários
Authors: Guimarães Rosana Córdova , Diniz Eduardo Henrique , Gonzalez Farias Lauro Emilio
Published: April 2018

Pagar contas, usar cartão de crédito, fazer seguro de vida... Como o brasileiro tem utilizado serviços como esses em seu cotidiano? Uma pesquisa da FGV-EAESP analisa o retrato da inclusão financeira no país
Os sete pecados capitais da educação corporativa
Authors: Wood Júnior Thomaz
Published: April 2018

Organizações de todo tipo e porte vêm investindo em sistemas de educação corporativa, mas os resultados são frustrantes. Identificamos alguns problemas que podem comprometer a eficácia desses sistemas.
Incentivos na medida certa
Authors: Sarti Fábio Dutra , Oliveira Antonio Carlos Manfredini
Published: April 2018

O desenho de incentivos pode ser determinante para o sucesso ou fracasso de um negócio. Um estudo avaliou na prática o seu impacto no atendimento a reclamações de um grande banco de varejo. Entenda a relevância disso para a sua carreira ou negócio.
Coaching: modo de usar
Authors: Pliopas Ana Luísa Vieira
Published: April 2018

Relativamente recente nas organizações, o coaching é uma ferramenta de desenvolvimento profissional e pessoal que serve, em última instância, para nos tornar versões um pouco melhores de nós mesmos.
A felicidade geral da nação
Authors: Caldas Eduardo de Lima
Published: April 2018

Já há muito que o desenvolvimento das nações deixou de ser visto como sinônimo de crescimento econômico. Hoje, a felicidade interna de um país é considerada tão importante quanto seu PIB. Será?
Tanto mar: alternativas à carreira executiva
Authors: Ogliara Marcio
Published: April 2018

Depois de construir uma carreira executiva no setor privado, um profissional experiente explora novos territórios e investiga como, afinal, é a vida, e se há mesmo felividade fora das corporações.
Marcas da competitividade
Authors: Rocha Ismael , Ponte Maurício Turra
Published: April 2018

A abertura progressiva das fronteiras nacionais criou um ambiente comercial em que proliferam em abundância opções de produtos e serviços para o consumidor global. Empresas e países competitivos são os que conseguem tornar seus produtos e serviços atrativos e diferenciados aos olhos desse exigente consumidor. O artigo discute a importância da internacionalização de uma marca forte do país no exterior e a contribuição de empresas nacionais pioneiras na acirrada disputa pelas vitrines do mercado mundial.
Da qualidade à infra-estrutura
Authors: Aidar Marcelo Marinho
Published: April 2018

Um balanço das principais iniciativas do governo para o fomento da competitividade do país inclui a elaboração de programas focados na disseminação de uma mentalidade orientada pela qualidade e produtividade nos mais diversos setores produtivos, públicos e privados. Além de apresentar tais programas, o artigo mostra que, hoje, um dos principais obstáculos à competitividade do Brasil é sua infra-estrutura, e destaca as ações realizadas na área, bem como os pontos críticos que devem ser contemplados em um esforço conjunto entre governo e empresas.
Competitividade nas alturas
Authors: Avrichir Ilan , Caldas Miguel Pinto
Published: April 2018

Na história da indústria aeronáutica brasileira, a Embraer destaca-se como um ícone respeitado. Modelo bem-sucedido em termos de inovação de produtos e conquista de mercados internacionais, a empresa é alvo de diversos pesquisadores que buscam, na compreensão de seu sucesso, a possibilidade de generalizar suas lições para outras áreas da indústria nacional. O artigo analisa as principais razões para o sucesso do modelo competitivo da Embraer e traz uma reflexão sobre as reais possibilidades de sua imitação.
Competitividade criativa
Authors: Borges Julio Daio
Published: April 2018

A convergência entre artes criativas tradicionais, indústrias culturais de massa e das novas tecnologias de informação tem impulsionado a emergência de uma economia cultural. Nesta, o modelo da produção em massa de bens tangíveis é substituído pela atividade criativa de geração de idéias, bens simbólicos e outras atividades culturais. O artigo analisa o estado da arte dessas indústrias no Brasil, destacando que o país reúne massa crítica necessária para ser competitivo nesse novo domínio.