bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between hospital financial performance and publicly reported outcomes
Authors: Nguyen Oanh Kieu , Halm Ethan A. , Makam Anil N.
Published: February 2016

BACKGROUND

Hospitals that have robust financial performance may have improved publicly reported outcomes.

OBJECTIVES

To assess the relationship between hospital financial performance and publicly reported outcomes of care, and to assess whether improved outcome metrics affect subsequent hospital financial performance.

DESIGN

Observational cohort study.

SETTING AND PATIENTS

Hospital financial data from the Office of Statewide Health Planning and Development in California in 2008 and 2012 were linked to data from the Centers for Medicare and Medicaid Services Hospital Compare website.

MEASUREMENTS

Hospital financial performance was measured by net revenue by operations, operating margin, and total margin. Outcomes were 30‐day risk‐standardized mortality and readmission rates for acute myocardial infarction (AMI), congestive heart failure (CHF), and pneumonia (PNA).

RESULTS

Among 279 hospitals, there was no consistent relationship between measures of financial performance in 2008 and publicly reported outcomes from 2008 to 2011 for AMI and PNA. However, improved hospital financial performance (by any of the 3 measures) was associated with a modest increase in CHF mortality rates (ie, 0.26% increase in CHF mortality rate for every 10% increase in operating margin [95% confidence interval: 0.07%‐0.45%]). Conversely, there were no significant associations between outcomes from 2008 to 2011 and subsequent financial performance in 2012 (P > 0.05 for all).

CONCLUSIONS

Robust financial performance is not associated with improved publicly reported outcomes for AMI, CHF, and PNA. Financial incentives in addition to public reporting, such as readmissions penalties, may help motivate hospitals with robust financial performance to further improve publicly reported outcomes. Reassuringly, improved mortality and readmission rates do not necessarily lead to loss of revenue. Journal of Hospital Medicine 2016;11:481–488. © 2016 Society of Hospital Medicine
Variability and trends of annual and seasonal thunderstorm frequency over Bangladesh
Authors: Saha Toma Rani , Quadir Dewan Abdul
Published: February 2016

The climatology of thunderstorm (TS) activities over Bangladesh has been investigated using monthly, seasonal, and annual time series data of 29 meteorological stations in the country for a maximum period of 35 years (1976–2010). The climatology of the TS and its inter‐annual variability and trends have been investigated using country average as well as station‐wise data. The results of the trend analysis show that the country average TS frequency exhibits statistically significant trends for annual and seasonal data, except for winter. The monthly TS frequency shows significant increasing trends for the months April–November. The station‐wise analysis of annual and seasonal data shows dominant increasing trends over the country, with a few stations having negative trends. The correlation coefficients of the time series of seasonal and annual TS frequency with rainfall and minimum and maximum temperature have been computed. Also, the composite climatology of geopotential height and temperature fields of the troposphere covering Bangladesh and its surrounding areas for the month of May individually for the years with high TS frequency and low TS frequency has been presented and analysed. The low level moisture and meridional component of wind fields have also been considered. Additionally, the correspondence of TS frequency for this month with the low level vertical wind shear (VWS) between 850 and 500 hpa levels for the u‐component of the wind has also been studied using the data of 1976–2010, which shows that the TS frequency is correlated with VWS.
Configuring Anion‐Exchange Membranes for High Conductivity and Alkaline Stability by Using Cationic Polymers with Tailored Side Chains
Authors: Jannasch Patric , Weiber Eva Annika
Published: February 2016

Polymeric anion‐exchange membranes (AEMs) are critical components for alkaline membrane fuel cells (AMFCs) which offer several attractive advantages including the use of platinum‐free catalysts and a wide choice of fuel. The development of AMFCs and other electrochemical energy systems is currently severely limited by the lack of AEMs with sufficient alkaline stability. Still, significant advances have been made in recent years and one of the most promising approaches to emerge is the design and synthesis of cationic polymers with various side chain arrangements. Especially, synthetic strategies where the cationic ion‐exchange groups are placed on pendant alkyl spacer chains along the backbone seem to significantly improve microphase separation, hydroxide ion conductivity, and alkaline stability in relation to standard AEMs with cations placed in benzylic positions directly on the backbone. This article reviews recent approaches to high‐performance cationic membrane polymers involving different side chain designs, and discusses some possible future directions.

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A Monte Carlo model for estimating tornado impacts
Authors: Strader Stephen M. , Pingel Thomas J. , Ashley Walker S.
Published: February 2016

Determining the likelihood and severity of tornado disasters requires an understanding of the dynamic relationship between tornado risk and vulnerability. As population increases in the future, it is likely that tornado disaster frequency and magnitude will amplify. This study presents the Tornado Impact Monte Carlo (TorMC) model, which simulates tornado events atop a user‐defined spatial domain to estimate the possible impact on people, the built‐environment or other potentially vulnerable assets. Using a Monte Carlo approach, the model employs a variety of sampling techniques on observed tornado data to provide greater insight into the tornado disaster potential for a location. Simulations based on 10 000 years of significant tornado events for the relatively high‐risk states of Alabama, Illinois and Oklahoma are conducted to demonstrate the model processes, and its reliability and applicability. These simulations are combined with a fine‐scale (100 m), residential built‐environment cost surface to illustrate the probability of housing unit impact thresholds for a contemporary year. Sample results demonstrate the ability of the model to depict successfully tornado risk, residential built‐environment exposure and the probability of disaster. Additional outcomes emphasize the importance of developing versatile tools that capture better the tornado risk and vulnerability attributes in order to provide precise estimates of disaster potential. Such tools can provide emergency managers, planners, insurers and decision makers a means to advance mitigation, resilience and sustainability strategies.
Two‐dimensional adaptive Fourier decomposition
Authors: Qian Tao
Published: February 2016

One‐dimensional adaptive Fourier decomposition, abbreviated as 1‐D AFD, or AFD, is an adaptive representation of a physically realizable signal into a linear combination of parameterized Szegö and higher‐order Szegö kernels of the context. In the present paper, we study multi‐dimensional AFDs based on multivariate complex Hardy spaces theory. We proceed with two approaches of which one uses Product‐TM Systems; and the other uses Product‐Szegö Dictionaries. With the Product‐TM Systems approach, we prove that at each selection of a pair of parameters, the maximal energy may be attained, and, accordingly, we prove the convergence. With the Product‐Szegö dictionary approach, we show that pure greedy algorithm is applicable. We next introduce a new type of greedy algorithm, called Pre‐orthogonal Greedy Algorithm (P‐OGA). We prove its convergence and convergence rate estimation, allowing a weak‐type version of P‐OGA as well. The convergence rate estimation of the proposed P‐OGA evidences its advantage over orthogonal greedy algorithm (OGA). In the last part, we analyze P‐OGA in depth and introduce the concept P‐OGA‐Induced Complete Dictionary, abbreviated as Complete Dictionary. We show that with the Complete Dictionary P‐OGA is applicable to the Hardy H2 space on 2‐torus. Copyright © 2016 John Wiley & Sons, Ltd.
An asymptotic model for the deformation of a transversely isotropic, transversely homogeneous biphasic cartilage layer
Authors: Vitucci G. , Argatov I. , Mishuris G.
Published: February 2016

In the present paper, an asymptotic model is constructed for the short‐time deformation of an articular cartilage layer modeled as transversely isotropic, transversely homogeneous biphasic material. It is assumed that the layer thickness is relatively small compared with the characteristic size of the normal surface load applied to the upper surface of the cartilage layer, while the bottom surface is assumed to be firmly attached to a rigid impermeable substrate. In view of applications to articular contact problems, it is assumed that the interstitial fluid is not allowed to escape through the articular surface. Copyright © 2016 John Wiley & Sons, Ltd.
Assessment of viscous energy loss and the association with three‐dimensional vortex ring formation in left ventricular inflow: In vivo evaluation using four‐dimensional flow MRI
Authors: Elbaz Mohammed S.M. , van der Geest Rob J. , Calkoen Emmeline E. , de Roos Albert , Lelieveldt Boudewijn P.F. , Roest Arno A.W. , Westenberg Jos J.M.
Published: February 2016

Purpose

To evaluate viscous energy loss and the association with three‐dimensional (3D) vortex ring formation in left ventricular (LV) blood flow during diastolic filling.

Theory and Methods

Thirty healthy volunteers were compared with 32 patients with corrected atrioventricular septal defect as unnatural mitral valve morphology and inflow are common in these patients. 4DFlow MRI was acquired from which 3D vortex ring formation was identified in LV blood flow at peak early (E)‐filling and late (A)‐filling and characterized by its presence/absence, orientation, and position from the lateral wall. Viscous energy loss was computed over E‐filling, A‐filling, and complete diastole using the Navier‐Stokes energy equations.

Results

Compared with healthy volunteers, viscous energy loss was significantly elevated in patients with disturbed vortex ring formation as characterized by a significantly inclined orientation and/or position closer to the lateral wall. Highest viscous energy loss was found in patients without a ring‐shaped vortex during E‐filling (on average more than double compared with patients with ring‐shape vortex, P < 0.003). Altered A‐filling vortex ring formation was associated with significant increase in total viscous energy loss over diastole even in the presence of normal E‐filling vortex ring.

Conclusion

Altered vortex ring formation during LV filling is associated with increased viscous energy loss. Magn Reson Med 77:794–805, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
MR fingerprinting using the quick echo splitting NMR imaging technique
Authors: Jiang Yun , Ma Dan , Jerecic Renate , Duerk Jeffrey , Seiberlich Nicole , Gulani Vikas , Griswold Mark A.
Published: February 2016

Purpose

The purpose of the study is to develop a quantitative method for the relaxation properties with a reduced radio frequency (RF) power deposition by combining magnetic resonance fingerprinting (MRF) technique with quick echo splitting NMR imaging technique (QUEST).

Methods

A QUEST‐based MRF sequence was implemented to acquire high‐order echoes by increasing the gaps between RF pulses. Bloch simulations were used to calculate a dictionary containing the range of physically plausible signal evolutions using a range of T1 and T2 values based on the pulse sequence. MRF‐QUEST was evaluated by comparing to the results of spin‐echo methods. The specific absorption rate (SAR) of MRF‐QUEST was compared with the clinically available methods.

Results

MRF‐QUEST quantifies the relaxation properties with good accuracy at the estimated head SAR of 0.03 W/kg. T1 and T2 values estimated by MRF‐QUEST are in good agreement with the traditional methods.

Conclusions

The combination of the MRF and the QUEST provides an accurate quantification of T1 and T2 simultaneously with reduced RF power deposition. The resulting lower SAR may provide a new acquisition strategy for MRF when RF energy deposition is problematic. Magn Reson Med 77:979–988, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Structural and resting‐state MRI detects regional brain differences in young and mid‐age healthy APOE‐e4 carriers compared with non‐APOE‐e4 carriers
Authors: Dowell Nicholas G. , Evans Simon L. , Tofts Paul S. , King Sarah L. , Tabet Naji , Rusted Jennifer M.
Published: February 2016

The presence of the e4 allele of the apolipoprotein E (APOE) gene is the best‐known genetic risk factor for Alzheimer's disease. In this study, we investigated the link between functional and behavioural differences and regional brain volume and cortical thickness differences in those who carry the e4 allele (e4+) and those who only carry the e3 allele (e3/e3). We studied these genotype populations in two age groups: a young group (average age, 21 years) and a mid‐age group (average age, 50 years). High‐resolution T1‐weighted MRI scans were analysed with Freesurfer to measure regional white matter brain volume and cortical thickness differences between genotype groups at each age. These data were correlated with behavioural findings in the same cohort. Resting‐state MRI was also conducted to identify differences in underlying brain functional connectivity. We found that there was a positive correlation between the thickness of the parahippocampal cortex in young e4+ individuals and performance on an episodic memory task. Young e4+ individuals also showed a positive correlation between white matter volume in the left anterior cingulate and performance on a covert attention task. At mid‐age, e4+ individuals had structural differences relative to e3/e3 individuals in these areas: the parahippocampal cortex was thicker and white matter volume in the left anterior cingulate was greater than in e3/e3 individuals. We discuss the possibility that an over‐engagement with these regions by e4+ individuals in youth may have a neurogenic effect that is observable later in life. The cuneus appears to be an important region for APOE‐driven differences in the brain, with greater functional connectivity among young e3/e3 individuals and greater white matter volume in young e4+ individuals. Copyright © 2016 John Wiley & Sons, Ltd.
Mathematical models and empirical analysis of a simulated annealing approach for two variants of the static data segment allocation problem
Authors: Sen Goutam , Krishnamoorthy Mohan , Rangaraj Narayan , Narayanan Vishnu
Published: February 2016

We consider a content distribution network (CDN) in which data hubs or servers are established in multiple locations to cater to local demands. The distributions of data to these hubs along with related network design problems (such as hub location and user assignment) are the key decision problems to consider to minimize the total routing cost. A new model for allocation of segments is introduced in Sen, Krishnamoorthy, Rangaraj and Narayanan, Comput Oper 62 (2015), 282–295, in which local preferences guide the database partitioning process, and the servers are fully connected to each other. In this article, we develop a simulated annealing (SA) approach (referred to as SA‐mesh) to solve this problem and compare its performance with the corresponding mixed‐integer linear programming (MILP) formulation. We also formulate a much harder variant of the problem in which servers are interconnected by a tree. We develop a SA algorithm (referred to as SA‐tree) for this variant, in which a local search is incorporated to find a suboptimal tree backbone. We use a customized data structure based on linked lists to represent a solution in our algorithms. This enables our algorithms to scale to much larger instances of the problem. We use optimal solutions and the benchmarks obtained by CPLEX to justify the performance of our algorithms. © 2016 Wiley Periodicals, Inc. NETWORKS, Vol. 68(1), 4–22 2016
Improved dispersion of attapulgite in polypropylene by grap oxide and the enhanced mechanical properties
Authors: Xia Yang , Zhu Yuanchao , Zhou Yifeng , Nie Wangyan , Chen Pengpeng
Published: February 2016

Attapulgite (ATT) is a one‐dimensional (1D) nanorod which shows great potential as an effective filler for enhancing polymers. However, natural ATT is hard to develop its nanoscale reinforce advantages because it always tend to aggregate in the matrix. In this work, hybrid filler composed of ATT nanorods attached on two‐dimensional (2D) graphene oxide (GO) nanoplatelets was prepared through electrostatic assembly, and then introduced into polypropylene (PP) matrix using melt blending method. A better dispersion of ATT in PP matrix was obtained with the aid of GO nanosheets. The tensile strength, Young's modulus and storage modulus of PP composites were improved simultaneously. Taking GO as an assistant‐dispersant is believed to be a novel design strategy and effective approach for developing high performance nanocomposites. POLYM. COMPOS., 39:560–568, 2018. © 2016 Society of Plastics Engineers
Cross–cultural Generalizability of the Alternative Five–factor Model Using the Zuckerman–Kuhlman–Aluja Personality Questionnaire
Authors: Rossier Jérôme , Aluja Anton , Blanch Angel , Barry Oumar , Hansenne Michel , Carvalho André F. , Valdivia Mauricio , Wang Wei , Desrichard Olivier , Hyphantis Thomas , Suranyi Zsuzsanna , Glicksohn Joseph , De Pascalis Vilfredo , León–Mayer Elizabeth , Piskunov Aleksei , Stivers Adam , Morizot Julien , Ostendorf Fritz , Čekrlija Đorđe , Bellaj Tarek , Markiewicz Dorota , Motevalian Abbas , Karagonlar Gokhan
Published: February 2016

Several personality models are known for being replicable across cultures, such as the Five–Factor Model (FFM) or Eysenck's Psychoticism–Extraversion–Neuroticism (PEN) model, and are for this reason considered universal. The aim of the current study was to evaluate the cross–cultural replicability of the recently revised Alternative FFM (AFFM). A total of 15 048 participants from 23 cultures completed the Zuckerman–Kuhlman–Aluja Personality Questionnaire (ZKA–PQ) aimed at assessing personality according to this revised AFFM. Internal consistencies, gender differences and correlations with age were similar across cultures for all five factors and facet scales. The AFFM structure was very similar across samples and can be considered as highly replicable with total congruence coefficients ranging from .94 to .99. Measurement invariance across cultures was assessed using multi–group confirmatory factor analyses, and each higher–order personality factor did reach configural and metric invariance. Scalar invariance was never reached, which implies that culture–specific norms should be considered. The underlying structure of the ZKA–PQ replicates well across cultures, suggesting that this questionnaire can be used in a large diversity of cultures and that the AFFM might be as universal as the FFM or the PEN model. This suggests that more research is needed to identify and define an integrative framework underlying these personality models. Copyright © 2016 European Association of Personality Psychology
Impact of Pill Burden on Adherence, Risk of Hospitalization, and Viral Suppression in Patients with HIV Infection and AIDS Receiving Antiretroviral Therapy
Authors: Scott Sutton S. , Magagnoli Joseph , Hardin James W.
Published: February 2016

Study Objective

To evaluate the impact of pill burden on outcomes in patients with human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome (AIDS) receiving antiretroviral therapy (ART) as a single‐tablet regimen (STR) or multiple‐tablet regimen (MTR).

Design

Retrospective cohort study.

Data Sources

South Carolina Medicaid medical and pharmacy paid claims data were obtained from the South Carolina Revenue and Fiscal Affairs Office; laboratory data were obtained from the South Carolina Department of Health and Environmental Control.

Patients

A total of 2174 patients covered by South Carolina Medicaid who were dispensed a complete ART STR (580 patients) or MTR (1594 patients) lasting at least 60 days between January 1, 2006, and December 31, 2013.

Measurements and Main Results

Outcomes were ART adherence; risk of, time to, and total number of hospitalizations; and viral load suppression. Patients were followed from the index date (start date of their complete ART regimen) until the earliest date of one of the following: treatment discontinuation; treatment switch from MTR to STR, or vice versa; end of study period; last date of Medicaid eligibility; or death. Differences in outcomes were evaluated by using bivariate χ2 and Wilcoxon rank sum tests, as well as multivariate regression models controlling for covariates measured during a 6‐month baseline period. The STR and MTR cohorts were, on average, similar in terms of age at index date, Charlson Comorbidity Index score, sex, drug abuse, and mental health diagnoses, but they differed significantly in racial composition, index year of regimen, previous treatment, baseline viral load, and CD4 measures. The bivariate analysis revealed that the STR cohort was more adherent (p<0.0001), had a lower risk of hospitalization (p=0.0076), and had a higher proportion of patients with viral suppression (64.5% vs 49.5%, p<0.0001). In addition, multivariate regression models revealed that the STR cohort was more adherent and was associated with a lower risk of hospitalization (hazard ratio 0.71, 95% confidence interval 0.59–0.86), but no significant difference in viral load suppression was noted between the STR and MTR cohorts.

Conclusion

The STR was associated with higher adherence rates and a lower risk of hospitalization (both in the adjusted and unadjusted analyses) in South Carolina Medicaid patients with HIV infection and AIDS. A higher proportion of patients in the STR cohort had viral suppression during the follow‐up period in the unadjusted analysis compared with the MTR cohort; however, no significant difference in viral suppression was observed when controlling for adherence.
Regular Hexagonal Gold Nanoprisms Fabricated by a Physical Method: Toward Use as Ultrasensitive Surface‐Enhanced Raman Scattering Substrates
Authors: Bai Yiming , Yan Lingling , Yin Zhigang , Wang Jun , Chen Nuofu , Chen Jikun , Tan Zhanao
Published: February 2016

A simple physical approach to prepare gold (Au) nanoparticles with sharp edges for increasing surface‐enhanced Raman scattering (SERS) response is presented. The shape evolution process of Au nanoparticles under different fabrication conditions is studied, and a thermodynamic model is adopted to explain the shape transition. Single‐crystalline Au nanoprisms with regular hexagonal shape can be formed at a certain annealing temperature. Coating of these Au nanoprisms with graphene causes them to exhibit a SERS enhancement of 60x. This is the first demonstration of a physical approach to fabricate regular hexagonal Au nanoprisms that exhibit an ultrasensitive SERS effect. Furthermore, the local field distribution of a series of Au nanoprisms with different sizes is simulated to better understand their ultrasensitive SERS performance.
Cold‐conveyor‐belt jet, sting jet and slantwise circulations in idealized simulations of extratropical cyclones
Authors: Coronel B. , Ricard D. , Rivière G. , Arbogast P.
Published: February 2016

The present study investigates the formation of sting‐jet cyclones using an idealized configuration of a high‐resolution mesoscale numerical model. The initial set‐up is composed of axisymmetric finite‐amplitude synoptic‐scale cyclones added to a baroclinic zonal jet. When the surface cyclone is initialized on the warm‐air side of the zonal jet, a strong bent‐back warm front forms, which is a favourable condition for sting jets. A rather high vertical resolution of about 200 m in the lower troposphere is required to obtain well‐formed slantwise circulations near the cloud head and to make the distinction between cold‐conveyor‐belt jet and sting jet. In contrast, when the surface cyclone is initialized on the jet axis, the surface cyclone is more representative of the Norwegian cyclone model and the bent‐back warm front is almost non‐existent.

Sting‐jet mechanisms are analyzed using backward Lagrangian trajectories. A minority group of air parcels entering the sting‐jet region undergoes diabatic cooling due to sublimation of snow and graupel. The majority group does not present such a diabatic cooling and corresponds to descending air masses from the cloud‐head region in a near‐neutral environment with respect to conditional symmetric instability. Indeed, the saturated moist potential vorticity is near zero and the momentum surfaces and saturated moist isentropes are quasi‐parallel in the main slantwise descent. The latter descent is shown to be geostrophically forced by the strong divergent component of the along‐front Q vector.

Boundary‐layer processes are also analyzed. In most areas, the static stability being strong, there is no penetration of descents coming from the sting jet into the boundary layer and the peaks in surface wind gusts are connected to intrinsic boundary‐layer convective cells and parametrized turbulence. Such a penetration occurs in some areas but is not related to the strongest wind gusts.
Repetitive dengue outbreaks in East Africa: A proposed phased mitigation approach may reduce its impact
Authors: Baba Marycelin , Villinger Jandouwe , Masiga Daniel K.
Published: February 2016

Dengue outbreaks have persistently occurred in eastern African countries for several decades. We assessed each outbreak to identify risk factors and propose a framework for prevention and impact mitigation. Seven out of ten countries in eastern Africa and three islands in the Indian Ocean have experienced dengue outbreaks between 1823 and 2014. Major risk factors associated with past dengue outbreaks include climate, virus and vector genetics and human practices. Appropriate use of dengue diagnostic tools and their interpretation are necessary for both outbreak investigations and sero‐epidemiological studies. Serosurvey findings during inter‐epidemic periods have not been adequately utilised to prevent re‐occurrence of dengue outbreaks. Local weather variables may be used to predict dengue outbreaks, while entomological surveillance can complement other disease‐mitigation efforts during outbreaks and identify risk‐prone areas during inter‐epidemic periods. The limitations of past dengue outbreak responses and the enormous socio‐economic impacts of the disease on human health are highlighted. Its repeated occurrence in East Africa refutes previous observations that susceptibility may depend on race. Alternate hypotheses on heterotypic protection among flaviviruses may not be applied to all ecologies. Prevention and mitigation of severe dengue outbreaks should necessarily consider the diverse factors associated with their occurrence. Implementation of phased dengue mitigation activities can enforce timely and judicious use of scarce resources, promote environmental sanitation, and drive behavioural change, hygienic practices and community‐based vector control. Understanding dengue epidemiology and clinical symptoms, as determined by its evolution, are significant to preventing future dengue epidemics. Copyright © 2016 John Wiley & Sons, Ltd.
Growth and Smoltification of Three Norwegian Strains of Atlantic Salmon Salmo salar Reared under Different Thermal Regimes
Authors: Imsland A. K. , Pettersen K. , Stefansson S. O.
Published: February 2016

A comparative study was performed with juvenile Atlantic salmon Salmo salar from three stocks in Western Norway that differ in their natural conditions. One is from warm, lowland river conditions (Årdal), one is from cold glacial river conditions (Stryn) and the last one (Suldalslågen) is from a hydropower‐regulated river. The salmon parr were tagged and reared at 4, 5.5 and 7 °C and simulated natural water temperature (SNT) for river Suldalslågen. Size distribution was unimodal at 4 °C, with a change to a bimodal distribution, representing potential 1+ and 2+ smolts, at the other temperature regimes. The relative biomass of 1+ smolts varied between the stocks as Stryn (cold glacial river) stock had the highest number of smolts at 7 °C and the Suldalsågen stock (hydropower‐regulated river) displaying the highest number at the SNT regime. Overall, the Stryn stock, originating from cold river conditions, seemed to be well adapted to growth and smoltification at cold temperatures, whereas salmon parr from river Suldalslågen seem to be better adapted to the natural temperature regime (SNT) of this river than the other two stocks. This was reflected in the gill Na+,K+‐ATPase as the Suldalslågen stock showed increasing activity from 16 April (4.2 µmol ADP mg protein−1 h−1) to 10 May (9.2 µmol ADP mg protein−1 h−1), and at the end of the experiment, enzyme activity in Suldalslågen stock was significantly higher than both Stryn (5.7) and Årdal (5.9 µmol ADP mg protein−1 h−1) stock. In contrast, the warm lowland stock, Årdal, fish had low Na+,K+‐ATPase activity with no distinct peak at any of the sampled dates from March through May. Copyright © 2016 John Wiley & Sons, Ltd.
A multilevel excess hazard model to estimate net survival on hierarchical data allowing for non‐linear and non‐proportional effects of covariates
Authors: Charvat Hadrien , Remontet Laurent , Bossard Nadine , Roche Laurent , Dejardin Olivier , Rachet Bernard , Launoy Guy , Belot Aurélien ,   the CENSUR Working Survival Group
Published: February 2016

The excess hazard regression model is an approach developed for the analysis of cancer registry data to estimate net survival, that is, the survival of cancer patients that would be observed if cancer was the only cause of death. Cancer registry data typically possess a hierarchical structure: individuals from the same geographical unit share common characteristics such as proximity to a large hospital that may influence access to and quality of health care, so that their survival times might be correlated. As a consequence, correct statistical inference regarding the estimation of net survival and the effect of covariates should take this hierarchical structure into account. It becomes particularly important as many studies in cancer epidemiology aim at studying the effect on the excess mortality hazard of variables, such as deprivation indexes, often available only at the ecological level rather than at the individual level. We developed here an approach to fit a flexible excess hazard model including a random effect to describe the unobserved heterogeneity existing between different clusters of individuals, and with the possibility to estimate non‐linear and time‐dependent effects of covariates. We demonstrated the overall good performance of the proposed approach in a simulation study that assessed the impact on parameter estimates of the number of clusters, their size and their level of unbalance. We then used this multilevel model to describe the effect of a deprivation index defined at the geographical level on the excess mortality hazard of patients diagnosed with cancer of the oral cavity. Copyright © 2016 John Wiley & Sons, Ltd.
Intra‐cluster correlation selection for cluster randomized trials
Authors: Westgate Philip M.
Published: February 2016

In this paper, we give focus to cluster randomized trials, also known as group randomized trials, which randomize clusters, or groups, of subjects to different trial arms, such as intervention or control. Outcomes from subjects within the same cluster tend to exhibit an exchangeable correlation measured by the intra‐cluster correlation coefficient (ICC). Our primary interest is to test if the intervention has an impact on the marginal mean of an outcome. Using recently developed methods, we propose how to select a working ICC structure with the goal of choosing the structure that results in the smallest standard errors for regression parameter estimates and thus the greatest power for this test. Specifically, we utilize small‐sample corrections for the estimation of the covariance matrix of regression parameter estimates. This matrix is incorporated within correlation selection criteria proposed in the generalized estimating equations literature to choose one of multiple working ICC structures under consideration. We demonstrate the potential power and utility of this approach when used in cluster randomized trial settings via a simulation study and application example, and we discuss practical considerations for its use in practice. Copyright © 2016 John Wiley & Sons, Ltd.
Chemical Signaling and Functional Activation in Colloidosome‐Based Protocells
Authors: Sun Shiyong , Li Mei , Dong Faqin , Wang Shengjie , Tian Liangfei , Mann Stephen
Published: February 2016

An aqueous‐based microcompartmentalized model involving the integration of partially hydrophobic Fe(III)‐rich montmorillonite (FeM) clay particles as structural and catalytic building blocks for colloidosome membrane assembly, self‐directed membrane remodeling, and signal‐induced protocell communication is described. The clay colloidosomes exhibit size‐ and charge‐selective permeability, and show dual catalytic functions involving spatially confined enzyme‐mediated dephosphorylation and peroxidase‐like membrane activity. The latter is used for the colloidosome‐mediated synthesis and assembly of a temperature‐responsive poly(N‐isopropylacrylamide)(PNIPAM)/clay‐integrated hybrid membrane. In situ PNIPAM elaboration of the membrane is coupled to a glucose oxidase (GOx)‐mediated signaling pathway to establish a primitive model of chemical communication and functional activation within a synthetic “protocell community” comprising a mixed population of GOx‐containing silica colloidosomes and alkaline phosphatase (ALP)‐containing FeM‐clay colloidosomes. Triggering the enzyme reaction in the silica colloidosomes gives a hydrogen peroxide signal that induces polymer wall formation in a coexistent population of the FeM‐clay colloidosomes, which in turn generates self‐regulated membrane‐gated ALP‐activity within the clay microcompartments. The emergence of new functionalities in inorganic colloidosomes via chemical communication between different protocell populations provides a first step toward the realization of interacting communities of synthetic functional microcompartments.
Surgical treatment for hydrosalpinx prior to in‐vitro fertilization embryo transfer: a network meta‐analysis
Authors: Tsiami A. , Chaimani A. , Mavridis D. , Siskou M. , Assimakopoulos E. , Sotiriadis A.
Published: February 2016

Objective

The presence of hydrosalpinx impairs the outcome of in‐vitro fertilization embryo transfer (IVF‐ET). Surgical methods to either aspirate the fluid or isolate the affected Fallopian tubes have been attempted as a means of improving outcome. The aim of this network meta‐analysis was to compare the effectiveness of surgical treatments for hydrosalpinx before IVF‐ET.

Methods

An electronic search of MEDLINE, Scopus, Cochrane Central Register of Controlled Trials (Central) and the US Registry of clinical trials for articles published from inception to July 2015 was performed. Eligibility criteria included randomized controlled trials of women with hydrosalpinx before IVF‐ET comparing ultrasound‐guided aspiration of the fluid, tubal occlusion, salpingectomy or no intervention. Ongoing pregnancy was the primary outcome and clinical pregnancy, ectopic pregnancy and miscarriage were secondary outcomes. A random‐effects network meta‐analysis synthesizing direct and indirect evidence from the included trials was carried out. We estimated the relative effect sizes as risk ratios (RRs) and obtained the relative ranking of the interventions using cumulative ranking curves. The quality of evidence according to GRADE guidelines, adapted for network meta‐analysis, was assessed.

Results

Proximal tubal occlusion (RR, 3.22 (95% CI, 1.27–8.14)) and salpingectomy (RR, 2.24 (95% CI, 1.27–3.95)) for treatment of hydrosalpinx were superior to no intervention for ongoing pregnancy. For an outcome of clinical pregnancy, all three interventions appeared to be superior to no intervention. No superiority could be ascertained between the three surgical methods for any of the outcomes. In terms of relative ranking, tubal occlusion was the best surgical treatment followed by salpingectomy for ongoing and clinical pregnancy rates. No significant statistical inconsistency was detected; however, the point estimates for some inconsistency factors and their CIs were relatively large. The small study number and sizes were the main limitations. The quality of evidence was commonly low/very low, especially when aspiration was involved, indicating that the results were not conclusive and should be interpreted with caution.

Conclusions

Proximal tubal occlusion, salpingectomy and aspiration for treatment of hydrosalpinx scored consistently better than did no intervention for the outcome of IVF‐ET. In terms of relative ranking, proximal tubal occlusion appeared to be the most effective intervention, followed by salpingectomy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.
Effect of maleated polypropylene as a compatibilizer and hyperbranched polyester as a processing aid on polypropylene‐wood flour biocomposites
Authors: Nevare Mahendra R. , Tatiya Pyus D. , Mahulikar Pramod P. , Gite Vikas V.
Published: February 2016

This work focused on two difficulties associated with preparation of polypropylene/wood flour (PP/WF) composites, viz. the compatibility of PP with WF and processing of the composites with high melt viscosity. Maleic anhydride‐grafted polypropylene (MAPP) was used in the preparation of PP composites to provide the compatibility between polymer and filler. Hyperbranched polyester (HBPE) was incorporated to check feasibility of it as a processing aid in the same. The PP/WF composites were formulated by melt compounding on a Brabender Plastograph EC. Blending effect of compatibilizer and processing aid HBPE on PP/WF biocomposites have been carried out on the basis of torque analysis, mechanical properties, morphology, and thermal stability. The investigation showed that HBPE improves the processibility of PP/WF composites than MAPP with respective to torque value. The mechanical and thermal properties slightly vary with change in relative proportion of MAPP and HBPE. J. VINYL ADDIT. TECHNOL., 24:179–184, 2018. © 2016 Society of Plastics Engineers
Nitrogen‐Rich Amino‐triazolium Salts Based on Binary 4,5‐Dicyano‐1,2,3‐triazolate (C4N5–) Anion
Authors: Wu Jin‐Ting , Zhang Jian‐Guo , Qin Jian , Yin Xin , Wu Le
Published: February 2016

A series of amino‐triazolium salts based on 4,5‐dicyano‐1,2,3‐triazolate (C4N5–) anion were synthesized for first time by means of facile deprotonation reactions. The ionic compounds were characterized by single‐crystal X‐ray diffraction, vibrational spectroscopy, and elemental analysis. The thermal stability of the salts was assessed by differential scanning calorimetry, which showed good thermal stabilities up to above 180 °C. The heats of formation of these salts were computed using the methods of isodesmic reactions. In addition, the sensitivities of the studied salts toward impact and friction were determined, and all salts were found to be neither impact (> 40 J) nor friction sensitive (> 360 N).
Clinicopathological Characteristics and Prognostic Factors of Patients with Siewert Type II Esophagogastric Junction Carcinoma: A Retrospective Multicenter Study
Authors: Matsuda Tatsuo , Kurokawa Yukinori , Yoshikawa Takaki , Kishi Kentaro , Misawa Kazunari , Ohi Masaki , Mine Shinji , Hiki Naoki , Takeuchi Hiroya
Published: February 2016

Background

The incidence of esophagogastric junction (EGJ) carcinoma is increasing, but its optimal surgical management remains controversial.

Methods

We retrospectively reviewed the database of 400 patients with Siewert type II EGJ carcinoma who were treated surgically at 7 institutions between March 1986 and October 2010. We examined the clinicopathological characteristics, prognostic factors, and risk factors associated with each recurrence pattern.

Results

The 5‐year overall survival rate of all patients with Siewert type II EGJ carcinoma was 58.4 %. Multivariate analysis showed that T and N stages were independent prognostic factors. We also found that the incidence of lower mediastinal lymph node metastasis (17.7 %) and para‐aortic lymph node metastasis (16.1 %) was relatively high. In addition, the para‐aortic lymph nodes (N = 39, 9.8 %) were the most frequent node recurrence site, followed by the mediastinal lymph nodes (N = 23, 5.8 %). Lung recurrence was more common than was peritoneal recurrence. Considering each type of recurrence, multivariate analysis showed that the differentiated type was associated with a higher risk of lung recurrence than was the undifferentiated type, and N stage (pN2–3) and positive venous invasion were independent risk factors for liver recurrence.

Conclusions

This study is one of the largest retrospective studies to evaluate patients with Siewert type II EGJ carcinoma. Para‐aortic and mediastinal lymph node metastasis and recurrence rates were relatively high. During the postoperative follow‐up of patients with differentiated Siewert type II EGJ carcinoma, patients should be monitored for lung recurrence more closely than that for peritoneal recurrence.
Vitrification of embryos and oocytes for fertility preservation in cancer patients
Authors: Kato Keiichi
Published: February 2016

As survival rates and the life expectancy of those with malignancy have increased, more women in their reproductive years are referred for fertility preservation. Chemotherapy and radiotherapy can severely affect ovarian function, and the effect is irreversible. Therefore, it is optimal to attempt fertility preservation before chemotherapy and radiotherapy are initiated. Oocyte and embryo cryopreservation is the most common option for fertility preservation in women. Several reports have proven that embryo and oocyte cryopreservation can achieve a successful pregnancy. This review discusses the impact of chemotherapy and radiotherapy on ovarian function, and the importance of oocyte and embryo cryopreservation for fertility preservation. In addition, the current status of pregnancy outcomes and potential for cryopreserved oocytes to result in live births in cancer patients was reviewed. This may provide useful information for decision‐making in cancer patients regarding oocyte and embryo cryopreservation and fertility preservation.
System identification and parameter estimation in mathematical medicine: examples demonstrated for prostate cancer
Authors: Hirata Yoshito , Morino Kai , Suzuki Taiji , Guo Qian , Fukuhara Hiroshi , Aihara Kazuyuki
Published: February 2016

We review our studies on how to identify the most appropriate models of diseases, and how to determine their parameters in a quantitative manner given a short time series of biomarkers, using intermittent androgen deprivation therapy of prostate cancer as an example. Recently, it has become possible to estimate the specific parameters of individual patients within a reasonable time by employing the information concerning other previous patients as a prior. We discuss the importance of using multiple mathematical methods simultaneously to achieve a solid diagnosis and prognosis in the future practice of personalized medicine.
MIGRATION AND THE EQUILIBRIUM PREVALENCE OF INFECTIOUS DISEASES
Authors: Mesnard Alice , Seabright Paul
Published: February 2016

This paper models how migration both influences and responds to differences in disease prevalence between cities and shows how the possibility of migration away from high-prevalence areas affects long-run steady state disease prevalence. We develop a dynamic framework where migration responds to the prevalence of disease, to the costs of migration and to the costs of living. The model explores how pressure for migration in response to differing equilibrium levels of disease prevalence generates differences in city characteristics such as land rents. Competition for scarce housing in low-prevalence areas can create segregation, with disease concentrated in high-prevalence “sinks”. We show that policies affecting migration costs affect the steady-state disease prevalences across cities. In particular, migration can reduce steady-state disease incidence in low-prevalence areas while having no impact on prevalence in high-prevalence areas. This suggests that, in some circumstances, public health measures may need to avoid discouraging migration away from high-disease areas.
BLACK AND WHITE FERTILITY, DIFFERENTIAL BABY BOOMS: THE VALUE OF EQUAL EDUCATION OPPORTUNITY
Authors: Tamura Robert , Simon Curtis , Murphy Kevin M.
Published: February 2016

This paper produces new estimates for white and black mortality and fertility at the state level from 1800(20)–2000. It produces new estimates of black and white schooling for this same period. Using a calibrated model of black and white parents, we fit the time series of black and white fertility and schooling. We then produce estimates of the benefits of equal education opportunity for blacks over the period 1820–2000. For the better part of US history, blacks have suffered from less access to schooling for their children than whites. This paper quantifies the magnitude of this discrimination. Our estimates of the welfare cost of this discrimination prior to the Civil War range between 0.5 and 20 times black wealth, and between 0.5 and 10 times black wealth prior to 1960. Further we find that the Civil Rights era was valued by blacks in the South by between 1% to 2% of wealth. Outside of the South, we find significant costs of discrimination prior to 1960, ranging from 6% to 150% of black wealth. For these divisions from 1960–2000, blacks have attained rough parity in schooling access. The welfare magnitudes are similar to the hypothetical gains to blacks if they had white mortality rates. We show that the model’s black and white human capital series are strongly, positively correlated with state output measures, black and white permanent incomes and black and white earnings.