bluuebunny/crossref_metadata_2025 huggingface dataset:
A qualitative cognitive appraisal of tourist harassment
Authors: Otoo Felix Elvis , Badu‐Baiden Frank , Kim Seongseop (Sam)
Published: March 2019

Although hostility against tourists has gained a respectable amount of research attention over the last two decades, tourist harassment has proved to be an elusive topic for researchers. This study makes an important contribution to the literature by demonstrating the multidimensional nature of tourist harassment, with attention paid to the application of cognitive appraisal theory. We argue the need for an in‐depth understanding of victims' perspective of tourist harassment. The study involved 19 on‐site interviews conducted in Ghana. The results show that tourists are subjected to aggressive and passive forms of harassment. The qualitative inquiry revealed that harassment has substantial effects on tourists' cognitive assessment, emotional response, coping strategy, destination image, and future intentions. Expressing annoyance and making behavioral adjustments were the more notable emotional and coping responses recorded. Although respondents were generally confident about recommending Ghana as a destination in spite of the harassment, they were divided in terms of their intentions to revisit the destination.
Impact Statement Coding of Self‐Related Thought in Women With Posttraumatic Stress Disorder
Authors: Philippi Carissa L. , Dahl Gregory , Jany Miranda , Bruce Steven E.
Published: March 2019

Clinical and empirical studies have documented significant alterations in self‐related thought in posttraumatic stress disorder (PTSD). To our knowledge, however, few studies have examined self‐referential cognition by analyzing survivors’ written impact statements in individuals whose PTSD is due to interpersonal trauma. In the current study, we performed a linguistic analysis of impact statements (i.e., descriptions of how the trauma has affected the survivors’ views of themselves, others, and the world) collected at the start of therapy from women with PTSD that was due to interpersonal trauma, with the goal of determining whether PTSD symptom clusters were associated with altered self‐referential thought. We found that higher levels of PTSD‐related hyperarousal symptoms were significantly associated with diminished self‐related word use, after controlling for depression severity, f2 = .31. Similarly, diminished negative self‐related word use was associated with higher levels of hyperarousal symptoms, f2 = .47. Our findings align with previous research that has provided evidence for a diminished sense of self in PTSD. These results may help inform targeted interventions aimed at improving social‐affective functions in PTSD and other psychiatric conditions.
The Impact of Military Status on Cognitive Processing Therapy Outcomes in the Community
Authors: Dillon Kirsten H. , LoSavio Stefanie T. , Henry Teague R. , Murphy Robert A. , Resick Patricia A.
Published: March 2019

Military‐affiliated individuals (i.e., active duty personnel and veterans) exhibit high rates of posttraumatic stress disorder (PTSD). Although existing evidence‐based treatments for PTSD, such as cognitive processing therapy (CPT), have demonstrated effectiveness with military‐affiliated patients, there is evidence to suggest these individuals do not benefit as much as civilians. However, few studies have directly compared the effects of PTSD treatment between civilian and military‐affiliated participants. The current study compared treatment outcomes of military‐affiliated and civilian patients receiving CPT. Participants with PTSD who were either civilians (n = 136) or military‐affiliated (n = 63) received CPT from community‐based providers in training for CPT. Results indicated that military‐affiliated participants were equally likely to complete treatment, Log odds ratio (OR) = 0.14, p = .648. Although military‐affiliated participants exhibited reductions in PTSD, B = −2.53, p < .001; and depression symptoms, B = −0.65, p < .001, they experienced smaller reductions in symptoms relative to civilians: B = 1.15, p = .015 for PTSD symptoms and B = 0.29, p = .029 for depression symptoms. Furthermore, variability estimates indicated there was more variability in providers’ treatment of military‐affiliated versus civilian participants (i.e., completion rates and symptom reduction). These findings suggest that military‐affiliated patients can be successfully retained in trauma‐focused treatment in the community at the same rate as civilian patients, and they significantly improve in PTSD and depression symptoms although not as much as civilians. These findings also highlight community providers’ variability in treatment of military‐affiliated patients, providing support for more military‐cultural training.
Effects on white‐tailed deer following eastern coyote colonization
Authors: Bragina Eugenia V. , Kays Roland , Hody Allison , Moorman Christopher E. , Deperno Christopher S. , Mills L. Scott
Published: March 2019

The expansion or recovery of predators can affect local prey populations. Since the 1940s, coyotes (Canis latrans) have expanded into eastern North America where they are now the largest predator and prey on white‐tailed deer (Odocoileus virginianus). However, their effect on deer populations remains controversial. We tested the hypothesis that coyotes, as a novel predator, would affect deer population dynamics across large spatial scales, and the strongest effects would occur after a time lag following initial coyote colonization that allows for the predator populations to grow. We evaluated deer population trends from 1981 to 2014 in 384 counties of 6 eastern states in the United States with linear mixed models. We included deer harvest data as a proxy for deer relative abundance, years since coyote arrival in a county as a proxy of coyote abundance, and landscape and climate covariates to account for environmental effects. Overall, deer populations in all states experienced positive population growth following coyote arrival. Time since coyote arrival was not a significant predictor in any deer population models and our results indicate that coyotes are not controlling deer populations at a large spatial scale in eastern North America. © 2019 The Wildlife Society.
A study of the impact of inhibitors of DNA binding‐1 on proliferation and migration in human colon carcinoma cells
Authors: Wu Xue‐Liang , Wang Li‐Kun , Xue Jun , Dai Yong‐Jun , Yang Dong‐Dong , Qu Ming , Guo Fei , Han Lei , Sun Guang‐Yuan
Published: March 2019

This study aims to explore the effect of an inhibitor of DNA binding‐1 (Id‐1) on the proliferation and migration of human colon carcinoma cell line SW480 and HT‐29. SW480 and HT‐29 cells transfected with Id‐1‐interference sequence were assigned to the experimental groups (inhibition groups 1 and 2), and SW480 and HT‐29 cells with blank interference sequence (blank groups) and blank load transfection (blank load groups) were assigned as the control groups. The expression of Id‐1 in six groups was detected by reverse transcription‐polymerase chain reaction (RT‐PCR) and Western blot. Cell proliferation in vitro was assessed by MTT assay. RT‐PCR and Western blot results demonstrated that the mRNA and protein expressions of Id‐1 in the inhibition group 1 were lower than those in the blank group 1 and blank load group 1. RT‐PCR and Western blot results revealed that the mRNA and protein expressions of Id‐1 were lower in the inhibition group 2 than in the blank group 2 and blank load group 2. The results of the growth curve revealed that proliferation ability was significantly weaker from the third day in the inhibition groups 1 and 2 than in the blank group and blank load group. Transwell chamber experiment and Matrigel invasion assay revealed that the number of Transwell cells significantly decreased in the inhibition groups 1 and 2 than in the blank groups and blank load groups (P < 0.01). Id‐1 significantly promotes the proliferation and migration of human colon carcinoma cell lines SW480 and HT‐29.
Disparities in impact of nasopharyngeal cancer: An analysis of global health burden
Authors: Ramsey Tam , Hojjat Houmehr , Yuhan Brian , Svider Peter F. , Eloy Jean Anderson , Folbe Adam J. , Raza Syed Naweed , Fribley Andrew M.
Published: March 2019

Objectives

Nasopharyngeal carcinoma has a unique worldwide racial and geographic distribution. Our objective was to evaluate socioeconomic disparities in the burden of nasopharyngeal cancer (NPC) between endemic and nonendemic regions.

Methods

To demonstrate trends regarding societal burden of NPC and socioeconomic development, national disability‐adjusted life year (DALY) rates and human development indices (HDI) between 1990 and 2015 were evaluated. Countries were divided based on the endemic versus nonendemic presence of NPC and further analyzed by HDI status as specified by the United Nations Development Program. Gini coefficients and concentration index were used to evaluate global equality in NPC burden over this period.

Results

Age‐standardized DALYs dropped from 36.1 in 1990 to 26.5 in 2015 (26.6% decline) (r = −0.991, P < 0.001). Lower socioeconomic countries harbored greater NPC burden upon controlling by endemic and nonendemic regions, as demonstrated by progressively negative concentration indexes. Health inequality was greater in nonendemic countries than in endemic countries (P < 0.01).

Conclusion

To our knowledge, this is the first study to investigate socioeconomic‐related changes in NPC burden using statistical tools such as the Gini coefficient and concentration index. Although the burden of NPC has steadily decreased, there remain persistent inequalities associated with socioeconomic disparities. Nasopharyngeal cancer burden is more pronounced in countries with lower HDI. Our results reinforce the importance of increasing resources for developing countries and continuing inquiry into the screening, diagnosis, and management of NPC.

Level of Evidence

NA Laryngoscope, 129:2482–2486, 2019
Sistrunk centennial: Evolution of a classic operation
Authors: Isaacson Glenn
Published: March 2019

Objectives/Hypothesis

To trace the evolution of the Sistrunk procedure.

Study Design

Historical review.

Methods

We reviewed historical materials in the English, French, and German literature including journal articles, book chapters, genealogical sources, and obituaries to identify the emerging concepts leading to the Sistrunk operation. These included references to the embryology of the thyroid and of the branchial apparatus as well as incremental advances in the surgical management of midline congenital cervical cysts and fistulae. PubMed, the Google Internet search engine, Archive.org, and Google Translate were primary investigational tools.

Results

Understanding of human embryology evolved rapidly in the mid and late 1800s. Discovery of the thyroglossal duct and its role in thyroid development led to improvements in existing surgery for thyroglossal duct remnants. Sistrunk was aware of the anatomy and histopathology of these remnants and used this knowledge to refine existing surgical approaches.

Conclusions

The elements of thyroglossal duct remnant surgery existed for decades before Sistrunk popularized his modified approach to dissection of the suprahyoid portion of the tract. His innovation and his clear description of the operation made it accessible to surgeons around the world.

Level of Evidence

NA Laryngoscope, 130:E45–E47, 2020
Open access journal publishing in the Nordic countries
Authors: Björk Bo‐Christer
Published: March 2019

The number of open access (OA) journals and their share of all scholarly journals are usually estimated based on indexing in the Directory of Open Access Journals (DOAJ). DOAJ's coverage of OA journals from different regions of the world is, however, far from complete, particularly of journals publishing in languages other than English. Using alternative data sources for identification and manual verification, 437 scholarly OA journals published in the five Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden) were identified, and some key characteristics were studied. Of these, only 184 were indexed in DOAJ. A vast majority of the journals was published by scholarly societies or universities. Social sciences and humanities dominated as topics, and few journals charge authors. National or university‐specific OJS portals have played a major role in enabling OA publishing. Around a third of the Nordic scholarly journals are currently OA.
Canolol Dimer, a Biologically Active Phenolic Compound of Edible Rapeseed Oil
Authors: Kraljić Klara , Brkan Veronika , Škevin Dubravka , Srček Višnja Gaurina , Radošević Kristina
Published: March 2019

Rapeseed and its oil are the source of many biologically active substances. From crude rapeseed oil, canolol is isolated and from edible oil its dimer. Herein, we tested the biological activity of those two compounds isolated from the oils by determining their antioxidant capacity and in vitro cytotoxicity on human tumor cell lines. Canolol and its dimer showed antiproliferative activity on both cell lines with IC50 values of 46.45 μM in HeLa, and 51.19 μM in MCF7 cells, respectively. Evaluation of cell death was also done, while the oxygen radical absorbance capacity method confirmed that the canolol dimer has higher antioxidant potential than canolol. Stability of canolol and its dimer under different storage conditions showed that for a longer period of time both compounds should be stored in a freezer, but also that the dimer is more stable against degradation than canolol. Presented results indicate possible applications of canolol and its dimer in the food and pharmaceutical industry as a natural antioxidant and an anticancer agent, respectively.
Adiponectin and Serine/Threonine Kinase Akt Modulation by Triiodothyronine and/or LY294002 in 3T3‐L1 Adipocytes
Authors: de Oliveira Miriane , Rodrigues Bruna Moretto , Olimpio Regiane Marques Castro , Mathias Lucas Solla , De Sibio Maria Teresa , Moretto Fernanda Cristina Fontes , Graceli Jones Bernardes , Nogueira Célia Regina
Published: March 2019

Adipose tissue (AT), an endocrine organ that modulates several physiological functions by synthesizing and releasing adipokines such as adiponectin, is a metabolic target of triiodothyronine (T3). T3 and adiponectin play important roles in controlling normal metabolic functions such as stimulation of fatty acid oxidation and increase in thermogenesis. The phosphatidylinositol 3‐kinase (PI3K) pathway is important for the differentiation of preadipocytes into adipocytes and can be activated by T3 for the transcription of specific genes, such as adiponectin. We examined the role of PI3K in adiponectin modulation by T3 action in murine adipocytes (3T3‐L1). The 3T3‐L1 adipocytes were treated with 1000 nM T3 for 1 h in the presence or absence of 50 μM LY294002 (LY), a PI3K inhibitor. Then, we assessed the expression of adiponectin and the phosphorylated serine/threonine kinase Akt (pAkt), a PI3K signaling protein, in the adipocytes. Adiponectin and pAKT levels were higher in the T3‐adipocyte cells, whereas in the LY group adiponectin was elevated and pAKT was decreased compared to the control (C). PI3K pathway inhibition for 1 h and posterior treatment with T3, in LY + T3, reduced the adiponectin level and increased pAKT levels compared to those in LY. T3 stimulated adiponectin levels by PI3K pathway activation and T3 can compensate alteration in the PI3K pathway, because with inhibition of the pathway it is able to maintain the basal levels of adiponectin and pAKT.
Dose‐response of human follicles during laser‐based hair removal: Ex vivo photoepilation model with classification system embracing morphological and histological features
Authors: van Vlimmeren Marijke A. A. , Raafs Bianca , Westgate Gillian , Beijens Linda G. M. , Uzunbajakava Natallia E.
Published: March 2019

Objectives

Photoepilation is a commonly used technology in home‐use devices (HUDs) and in professional systems to remove unwanted body hair using pulses of laser or intense pulsed light (IPL). Albeit HUDs and professional systems operate at different fluences and treatment regimes, both demonstrate high hair reduction. The underlying mechanisms, however, remain unknown partly due to high divergence of the existing literature data. The objective of this study was to develop an ex vivo photoepilation model with a set of criteria evaluating response to light pulses; and to investigate dose‐response behavior of hair follicles (HFs) subjected to a range of fluences.

Methods

After ex vivo treatment (single pulse, 810 nm, 1.7–26.4 J/cm2, 4–64 ms pulse) human anagen HFs were isolated and maintained in culture for 7–10 days. Response to light was evaluated based on gross‐morphology and histological examination (H&E and TUNEL stainings).

Results

HFs treated ex vivo demonstrated a dose‐dependent response to light with five distinct classes defined by macroscopic and microscopic criteria. Fluences below 13.2 J/cm2 provoked catagen‐like transition, higher fluences resulted in coagulation in HF compartments.

Conclusion

Observed changes in the HF organ culture model were reflected by clinical efficacy. The developed photoepilation model provides an easy and fast method to predict clinical efficacy and permanency of light‐based hair removal devices. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.
Polyacrylonitrile‐carbon Nanotube‐polyacrylonitrile: A Versatile Robust Platform for Flexible Multifunctional Electronic Devices in Medical Applications
Authors: Dinh Toan , Dau Van , Tran Canh‐Dung , Nguyen Tuan‐Khoa , Phan Hoang‐Phuong , Nguyen Nam‐Trung , Dao Dzung Viet
Published: March 2019

Flexible multifunctional electronic devices are of high interest for a wide range of applications including thermal therapy and respiratory devices in medical treatment, safety equipment, and structural health monitoring systems. This paper reports a scalable and efficient strategy of manufacturing a polyacrylonitrile‐carbon nanotube‐polyacrylonitrile (PAN‐CNT‐PAN) robust flexible platform for multifunctional electronic devices including flexible heaters, temperature sensors, and flexible thermal flow sensors. The key advantages of this platform include low cost, porosity, mechanical robustness, and electrical stability under mechanical bending, enabling the development of fast‐response flexible heaters with a response time of ≈1.5 s and relaxation time of ≈1.7 s. The temperature‐sensing functionality is also investigated with a range of temperature coefficient of resistances from −650 to −900 ppm K−1. A flexible hot‐film sensing concept is successfully demonstrated using PAN‐CNT‐PAN with a high sensitivity of 340 mV (m s−1)−1. The sensitivity enhancement of 50% W−1 is also observed with increasing supply power. The low cost, porosity, versatile, and robust properties of the proposed platform will enable the development of multifunctional electronic devices for numerous applications such as flexible thermal management, temperature stabilization in industrial processing, temperature sensing, and flexible/wearable devices for human healthcare applications.
Super‐Tough and Highly‐Ductile Poly(l‐lactic acid)/Thermoplastic Polyurethane/Epoxide‐Containing Ethylene Copolymer Blends Prepared by Reactive Blending
Authors: Lin Wangyang , He Yue , Qu Jin‐Ping
Published: March 2019

Ethylene‐methyl acrylate‐glycidyl methacrylate copolymer (E‐MA‐GMA) is employed to improve the impact toughness of poly(l‐lactic acid) (PLLA)/thermoplastic polyurethane (TPU) blends by reactive melt‐blending. The reaction and miscibility between the components are confirmed by Fourier transform infrared spectroscopy, dynamic mechanical analysis, and differential scanning calorimetry. A super‐tough PLLA/TPU/E‐MA‐GMA multiphase blend (75/10/15) exhibits a significantly improved impact strength of 77.77 kJ m−2, which is more than 17 times higher than that of PLLA/TPU (90/10) blend. A co‐continuous‐like TPU phase structure involving E‐MA‐GMA phase at the etched cryo‐fractured surface and the high‐orientated matrix deformation at the impact‐fractured surface are observed by scanning electron microscopy. The high‐orientated matrix deformation induced by the co‐continuous TPU phase structure is responsible for the super toughness of PLLA/TPU/E‐MA‐GMA blends.
Proanthocyanidin‐Induced Horizontal Arrangement in Poly(vinyl alcohol)/Graphene Composites with Enhanced Mechanical Properties
Authors: Wang Chao , Wen Min , Guo Le , Zhang Boyu , Ming Tingzhen , Huang Fuzhi , Zhang Qi
Published: March 2019

A green approach is employed to prepare mechanically enhanced composites by adding noncovalently proanthocyanidin (PC)‐modified graphene (PC‐rGO) into poly(vinyl alcohol) (PVA). Ascorbic acid (AA) is used as the reducing agent, and PC is used as a dispersant to synthesize low‐defect and fully dispersed graphene. After static treatment, the PC‐rGO sheets in the composite form a horizontally arranged structure. Compared with neat PVA, the Young's modulus of the graphene‐modified composites is significantly enhanced by approximately 79.3% with incorporation of 0.9 wt% PC‐rGO. The composites incorporated with GO or AA‐rGO (without PC) have randomly distributed GO structures and apparent rGO agglomeration, resulting in a weaker mechanical property. The dispersibility, degree of defects, distribution state of graphene, and interactions with the polymer matrix are directly related to the final mechanical performance. This new approach to mechanically enhance graphene‐embedded PVA composites provides the possibility for large‐scale production of graphene‐reinforced composite materials.
High Potential of Aerosol‐Made 3D Graphene‐Based Composites for Enhanced Energy Storage
Authors: Kim Sun Kyung , Ha Taehyeong , Lee Chongmin , Chang Hankwon , Jang Hee Dong
Published: March 2019

Recently, many researchers have developed advanced energy storage and energy conversion systems to address the increased demand for energy resources. The performance of these electrochemical energy storage and conversion devices depends considerably on the properties of their unique electrode materials. Among electrode materials, graphene (GR) has attracted much attention due to its unique properties of high flexibility, a large specific surface area, and superior electric conductivity rates that are well‐suited to energy storage systems. Specifically, aerosol‐made 3D GR composites are known to be more resistant to compressive forces such as paper balls owing to their stronger and harder compressive tolerance levels and higher and more stable surface areas compared to 2D GR sheets. These unique properties of 3D GR composites result in enhanced electrochemical performances for energy storage systems. This review focuses on recent studies of aerosol‐made 3D GR‐based composites for energy storage systems such as supercapacitors, lithium‐ion batteries, and sodium‐ion batteries.
Wave simulations of Gray‐Scott reaction‐diffusion system
Authors: Tok‐Onarcan Aysun , Adar Nihat , Dag Idiris
Published: March 2019

In this work, we study the numerical simulation of the one‐dimensional reaction‐diffusion system known as the Gray‐Scott model. This model is responsible for the spatial pattern formation, which we often meet in nature as the result of some chemical reactions. We have used the trigonometric quartic B‐spline (T4B) functions for space discretization with the Crank‐Nicolson method for time integration to integrate the nonlinear reaction‐diffusion equation into a system of algebraic equations. The solutions of the Gray‐Scott model are presented with different wave simulations. Test problems are chosen from the literature to illustrate the stationary waves, pulse‐splitting waves, and self‐replicating waves.
Convergence analysis of finite volume scheme for nonlinear aggregation population balance equation
Authors: Singh Mehakpreet , Kaur Gurmeet
Published: March 2019

In this work, we introduce the convergence analysis of the recently developed finite volume scheme to solve a pure aggregation population balance equation that is of substantial interest in many areas such as chemical engineering, aerosol physics, astrophysics, polymer science, pharmaceutical sciences, and mathematical biology. The notion of the finite volume scheme is to conserve total mass of the particles in the system by introducing weight in the formulation. The consistency of the finite volume scheme is also analyzed thoroughly as it is an influential factor. The convergence study of the numerical scheme shows second order convergence on uniform, nonuniform smooth (geometric) as well as on locally uniform meshes independent of the aggregation kernel. Moreover, the first‐order convergence is shown when the finite volume scheme is implemented on oscillatory and random meshes. In order to check the accuracy, the numerical experimental order of convergence is also computed for the physically relevant as well as analytically tractable kernels and validated against its analytical results.
Perturbation analysis for mixed least squares–total least squares problems
Authors: Zheng Bing , Yang Zhanshan
Published: March 2019

In many linear parameter estimation problems, one can use the mixed least squares–total least squares (MTLS) approach to solve them. This paper is devoted to the perturbation analysis of the MTLS problem. Firstly, we present the normwise, mixed, and componentwise condition numbers of the MTLS problem, and find that the normwise, mixed, and componentwise condition numbers of the TLS problem and the LS problem are unified in the ones of the MTLS problem. In the analysis of the first‐order perturbation, we first provide an upper bound based on the normwise condition number. In order to overcome the problems encountered in calculating the normwise condition number, we give an upper bound for computing more effectively for the MTLS problem. As two estimation techniques for solving the linear parameter estimation problems, interesting connections between their solutions, their residuals for the MTLS problem, and the LS problem are compared. Finally, some numerical experiments are performed to illustrate our results.
Ambulance nurses' experiences of deciding a patient does not require ambulance care
Authors: Backman Tess , Juuso Päivi , Borg Ronja , Engström Åsa
Published: March 2019

Aim

To describe ambulance nurses' experience of deciding a patient does not require ambulance care.

Design

An inductive, empirical study with a qualitative approach.

Methods

Data collection was conducted through semi‐structured interviews, and collected data were analysed with qualitative manifest content analysis. Data were collected during the spring 2017, and eight ambulance nurses participated.

Results

The findings are presented in one main category, which is “Not very ill but a difficult decision” with totally three subcategories. The ambulance nurse's experience of making the assessment when the patient has no need for ambulance care is like walking the balance of slack line. This means that the assessment can be both easy and very difficult but something that definitely requires experience, knowledge and dedication.
Challenges in municipality healthcare services—The nurse leaders' perspective
Authors: Søreide Hilde , Kyrkjebø Dagrun , Råholm Maj‐Britt
Published: March 2019

Aim

To examine perceptions of key challenges that nursing leadership face when organizing healthcare services in the municipality.

Design

A qualitative study involving community nurse leaders (N = 9) in two focus group interviews.

Methods

The material has been processed and interpreted in accordance with the phenomenological‐hermeneutical tradition, and this process was inspired by Graneheim and Lundman.

Results

Three themes were identified in this study: (a) Tension between organizing the daily work and future challenges; (b) Challenges with recruiting enough registered nurse (RNs) in municipal healthcare services; and (c) Competence development plan—a strategic tool for nursing leadership. The municipal healthcare services need a better knowledge base with better knowledge of both the content and quality of services, organization, leadership and management, thus improving new forms of work and professional approaches.
Effect of magnetite nanoparticles and their surface modification on the mechanical and magnetic properties of silicon‐based magnetic elastomer nanocomposite
Authors: Zuluaga‐Parra Jose David , Sanchez‐Valdes Saul , Ramos‐de Valle Luis F. , Flores‐Gallardo Sergio , Uribe‐Calderón Jorge A. , Beltrán‐Ramírez Flora I. , Romero‐García Jorge , Narro‐Céspedes Rosa I. , Morales‐Cepeda Ana Beatriz , Lozano‐Ramírez Tomas , Rodriguez‐Gonzalez Jose Alberto
Published: March 2019

Silicon nanocomposites were prepared with unmodified and modified magnetite nanoparticles in order to study the effect of the fatty acid modification on the curing reaction and thereafter on the mechanical and magnetic properties of the filled silicon‐based elastomer. Magnetite nanoparticles were first surface modified with oleic and stearic acid. Silicon nanocomposites with unmodified and modified magnetite nanoparticles were prepared by predispersing the nanoparticles in the silicone with the curing agent using toluene and ultrasound assisted mixing. The effect of the magnetite on the crosslinking reaction was studied in a rubber process analyzer instrument. At first, the addition of 1 wt% of magnetite decreased the induction time and increased the maximum torque, but upon increasing the magnetite content, this time increased and the maximum torque decreased. However, all the nanocomposites showed an induction time much lower than that of the pure silicon and a maximum torque much higher than that of the pure silicon. Unmodified magnetite nanocomposites showed a heterogeneous saturation magnetization when magnetite nanoparticles were modified with oleic and stearic acid. This resulted in homogeneous and replicable properties, attributed to the improvement in nanoparticles dispersion and distribution within the polymer matrix. The high saturation magnetization values of composites with unmodified magnetite compared with those with modified magnetite confirm that modified magnetite presented the best dispersion and more homogeneous magnetic properties. The Fourier‐transform infrared spectroscopy analysis suggests that the magnetite nanoparticles coating could be reacting with the silicon hydrosilane group which in turn decreases the attainable crosslinking level. With respect to the tensile properties, the tensile stress, as well as the elongation at the breakpoint decrease, in general, with increasing the magnetite content. POLYM. COMPOS., 40:3981–3988, 2019. © 2019 Society of Plastics Engineers
Is traditional perinatal autopsy needed after detailed fetal ultrasound and post‐mortem MRI?
Authors: Shelmerdine Susan C. , Arthurs Owen J. , Gilpin Isobel , Norman Wendy , Jones Rod , Taylor Andrew M. , Sebire Neil J. , Chitty Lyn S.
Published: March 2019

Objective

To determine the additional yield from autopsy following prenatal ultrasound and post‐mortem magnetic resonance imaging (PMMR) for structural abnormalities.

Method

PMMR was performed on consecutive fetuses over a 6‐year period. Prenatal ultrasound and PMMR findings were categorised as concordant, partially concordant or discordant findings. The yield of new and clinically significant information from autopsy was assessed. Diagnostic accuracies for both modalities were calculated, using autopsy as reference standard.

Results

Our study consisted of 81 fetuses. PMMR and prenatal ultrasound findings were concordant in 44/81 (54.3%), partially concordant in 26/81 (32.1%) and discordant in 11/81 (13.6%) cases. In 19/81 cases (23%), autopsy provided additional information, which appeared clinically significant in 12 cases. In 10 of those 12 cases, there was discordance between PMMR and ultrasound. In only 2 of 44 cases where ultrasound and PMMR were concordant, did autopsy provide clinically significant information.

Diagnostic accuracy rates for ultrasound were sensitivity of 76.8% (66.6%, 84.6%), specificity of 92.5% (88.9%, 95.0%). For PMMR the sensitivity was 79.0% (68.9%, 86.5%), specificity 97.9% (95.5%, 99.0%). PMMR had a significantly higher concordance rate with autopsy than ultrasound (89.0 vs 93.8%; P < .001).

Conclusion

Where PMMR and ultrasound are concordant, there is little additional yield from autopsy.
Association Between Time‐in‐Therapeutic Tacrolimus Range and Early Rejection After Heart Transplant
Authors: Baker William L. , Steiger Samantha , Martin Spencer , Patel Nirav , Radojevic Joseph , Darsaklis Konstadina , O'Bara Lynn , Kutzler Heather , Dougherty James , Feingold Andrew , Hammond Jonathan , Fusco Daniel , Gluck Jason A
Published: March 2019

Background

Historically, there is perceived pressure to achieve therapeutic levels of tacrolimus quickly after heart transplant (HT). We evaluated the association between time within therapeutic tacrolimus range and time to therapeutic trough and rejection in the 30 days following HT.

Methods

This is a single‐center retrospective cohort study of consecutive adult HT patients receiving immunosuppression. Goal trough tacrolimus levels were 10–15 ng/ml. Surveillance endomyocardial biopsies were performed weekly for 4 weeks. Outcomes included the effect of time to and time‐in‐therapeutic tacrolimus range (Rosendaal method) on 30‐day clinical rejection, 1R/1B, and 2R or higher histologic occurrences.

Results

We reviewed 67 HT patients (median age 58.8 yrs). For clinical rejection versus no‐rejection groups, the median (25th, 75th percentile) time to therapeutic tacrolimus levels was 9.5 (8, 12.3) days versus 9.0 (7, 13) days (p=0.623). The median time‐in‐therapeutic tacrolimus range was 34.1% (23.2, 42.2) versus 36.2% (19.9, 51.2), respectively (p=0.512). Similarly, we observed no significant differences in time to and time‐in‐therapeutic tacrolimus range in patients who developed grade 1R/1B (p=0.650 and p=0.725) or grade 2R or higher histology (p=0.632 and p=0.933).

Conclusions

Our small single‐center analysis suggests that neither time to nor time in therapeutic tacrolimus range predicted acute rejection within 30 days of HT.
Effects of Norepinephrine and Vasopressin Discontinuation Order in the Recovery Phase of Septic Shock: A Systematic Review and Individual Patient Data Meta‐Analysis
Authors: Hammond Drayton A. , Sacha Gretchen L. , Bissell Brittany D. , Musallam Nadine , Altshuler Diana , Flannery Alexander H. , Lam Simon W. , Bauer Seth R.
Published: March 2019

Objective

The impact of vasopressin and norepinephrine discontinuation order in the recovery phase of septic shock remains controversial. This systematic review and patient‐level meta‐analysis were performed to determine the impact of vasopressin and norepinephrine discontinuation order on clinically significant outcomes in the recovery phase of septic shock.

Methods

Cumulative Index to Nursing and Allied Health Literature, Embase, PubMed, and ClinicalTrials.gov were searched from inception through November 2018 for studies comparing outcomes after the discontinuation of vasopressin or norepinephrine in septic shock. Individual patient‐level data were obtained from included studies and combined using a two‐stage meta‐analysis.

Results

Six studies of low or moderate risk of bias with 957 patients were included. Clinically significant hypotension occurred more frequently when vasopressin was discontinued first compared to norepinephrine (60.7% versus 43.3%, respectively). First discontinuation of norepinephrine compared to vasopressin had lower pooled odds of developing clinically significant hypotension (odds ratio [OR] 0.22, 95% confidence interval [CI] 0.07–0.68, I2 87%). No differences were detected in short‐term mortality (OR 1.12, 95% CI 0.67–1.86, I2 45%), intensive care unit length of stay (mean difference 0.15 day, 95% CI −1.58 to 1.88, I2 21%), or hospital length of stay (mean difference 1.65 days, 95% CI −0.47 to 3.76, I2 0%).

Conclusions

Discontinuation of norepinephrine prior to vasopressin during the recovery phase of septic shock resulted in less clinically significant hypotension but no difference in mortality or lengths of stay. Larger, prospective studies evaluating the impact of relative vasopressin deficiency and norepinephrine and vasopressin discontinuation order and timing on patient‐centered outcomes are needed.
All‐solution‐processed transparent front contact for monograin layer kesterite solar cells
Authors: Edinger Stefan , Bansal Neha , Wibowo Adhi Rachmat , Winkler Nina , Illich Peter , Zechmeister Armin , Plessing Lukas , Meissner Dieter , Dimopoulos Theodoros
Published: March 2019

The paper presents a fully solution‐processed transparent front contact for kesterite monograin layer solar cells, which is composed of a silver nanowire network above a ZnO‐based window bilayer. This window bilayer comprises a layer of ZnO nanoparticles and a second layer of chemical‐bath‐deposited doped ZnO. The optimized front contact can be processed within minutes and performs equally to a reference front contact with a sputtered iZnO/ZnO:Al window bilayer, both on solar cell and module level with sizes up to 20 × 20 cm2. To achieve this, it was necessary to obtain a compact morphology of the chemical‐bath‐deposited, doped ZnO film even for very short deposition times. It is found that, firstly, this depends on the homogeneity of the seed layer, which is the prerequisite for thin film growth by chemical bath deposition (CBD) on the substrate. It is shown that the ZnO nanoparticle layer covers the rough monograin substrate in a continuous and unperturbed manner. The second aspect of importance was the dopant type used in the CBD process (Al, Ga, or In). Optimal combination of photovoltaic performance and process speed was obtained for Ga‐doped ZnO, yielding compact films for deposition times as low as 1 minute. The solution‐processed window layers are susceptible to a light‐soaking effect, which impairs the cell performance upon storage in dark conditions. While this effect can be easily overcome in the laboratory, the effect in a real application scenario was investigated under outdoor conditions for a period of 4 weeks.
GPX4 at the Crossroads of Lipid Homeostasis and Ferroptosis
Authors: Forcina Giovanni C. , Dixon Scott J.
Published: March 2019

Oxygen is necessary for aerobic metabolism but can cause the harmful oxidation of lipids and other macromolecules. Oxidation of cholesterol and phospholipids containing polyunsaturated fatty acyl chains can lead to lipid peroxidation, membrane damage, and cell death. Lipid hydroperoxides are key intermediates in the process of lipid peroxidation. The lipid hydroperoxidase glutathione peroxidase 4 (GPX4) converts lipid hydroperoxides to lipid alcohols, and this process prevents the iron (Fe2+)‐dependent formation of toxic lipid reactive oxygen species (ROS). Inhibition of GPX4 function leads to lipid peroxidation and can result in the induction of ferroptosis, an iron‐dependent, non‐apoptotic form of cell death. This review describes the formation of reactive lipid species, the function of GPX4 in preventing oxidative lipid damage, and the link between GPX4 dysfunction, lipid oxidation, and the induction of ferroptosis.
Highly alkaline stable anion exchange membranes from nonplanar polybenzimidazole with steric hindrance backbone
Authors: Ma Hongmei , Zhu Hong , Wang Zhongming
Published: March 2019

The anion exchange membranes (AEMs) with both high ionic conductivity and alkali stability are always the research focus of the AEM fuel cells. Here, a novel nonplanar polymer for AEMs manufacture, mPBI‐TP‐x‐R, with excellent hydroxide stability and satisfactory processability is reported for the first time. The serial mPBI‐TP‐x resins with steric hindrance were prepared by copolymerization among 3,3′,4,4′‐tetraaminobiphenyl, isophthalic acid and tetraphenyl‐terephthalic acid (TP) in different ratios under microwave condensation. The copolymers mPBI‐TP‐x were quaternized at N1/N3‐sites of benzimidazole unit in backbone with alkyl groups (RCH3, C2H5, n‐C3H7, or n‐C4H9) to prepare soluble ionomers, and the corresponding membranes in hydroxyl ion form were prepared by a solution casting method and subsequent ion‐exchange process. The chemical structure of all membranes was characterized using FTIR and 1H NMR spectroscopy. The properties of ion exchange capacity, water uptake, swelling ratio, tensile strength, ionic conductivity, and alkaline stability were measured. Among the prepared membranes, the mPBI‐TP‐15%‐(n‐Bu) exhibited the excellent alkaline stability (only degradation ca. 5% under 1M NaOH aqueous solution at 60 °C for 800 h) and satisfactory OH− conductivity (46.66 mS/cm at 80 °C). The current research provides a useful exploration to commercial application of alkaline fuel cell. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1087–1096
Absorbed weak polyelectrolytes: Impact of confinement, topology, and chemically specific interactions on ionization, conformation free energy, counterion condensation, and absorption equilibrium
Authors: Tagliabue Andrea , Izzo Lorella , Mella Massimo
Published: March 2019

Absorption of weak polyelectrolytes impacts on properties such as ionization, conformations, and counterion (CI) condensation that are important in several areas of applied and fundamental science. We used a weak polyelectrolyte model and Monte Carlo simulations to investigate how the mentioned properties depend on pH or the size of a spherical cavity (SC) permeable to CIs but not to polyelectrolytes; the latter have either linear or starlike topologies and may be allowed to form charged hydrogen bonds (cH‐bonds) between ionized and neutral monomers. Average ionization decreases upon increasing the number of arms at a constant number of monomers; it instead increases with the arm length in large SC due to CI screening. The way SC size, cH‐bonds, and pH values interrelate to define ionization is instead more complicate due to arm pairing or clustering when cH‐bonds are possible. These induce oscillations in the arm local ionization and impact on both monomer and CI distributions in the complete simulation cell in a way that also depends on polymer topology. The impact of ionization on the confinement free energy is also estimated; this highlighted that cH‐bonding may enhance absorption compared with neutral chains. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 491–510
Deliberate Introduction of Particle Anisotropy in Helical Gold Nanoparticle Superstructures
Authors: Mokashi‐Punekar Soumitra , Rosi Nathaniel L.
Published: March 2019

Helical nanoparticle (NP) superstructures are an important class of chiral NP assemblies. The nature of the constituent NPs (size and shape) within these assemblies dictates their optical properties. However, the construction of helical NP superstructures consisting of various anisotropic NPs remains challenging. Here, a set of cetyltrimethylammonium bromide derivatives is employed to transform constituent spherical gold NPs (≈3 nm) within a chiral single‐helical assembly into gold nanoprisms (edge length ≅ 10 nm). Careful optimization of this strategy may lead to designed chiral NP architectures with tunable optical properties.
Enhanced metabolism causes reduced flufenacet sensitivity in black‐grass (Alopecurus myosuroides Huds.) field populations
Authors: Dücker Rebecka , Zöllner Peter , Parcharidou Evlampia , Ries Susanne , Lorentz Lothar , Beffa Roland
Published: March 2019

BACKGROUND

Black‐grass (Alopecurus myosuroides Huds.) is a frequent grass weed that commonly occurs in winter wheat in temperate Europe. Evolving resistance to post‐emergence herbicides, e.g. acetyl CoA carboxylase (ACCase) and acetolactate synthase (ALS) inhibitors requires more complex weed management strategies and ensuring good efficacy of pre‐emergence treatments becomes increasingly important. Flufenacet, in particular, has become a key herbicide for the control of multiple‐resistant A. myosuroides. However, in some of those populations, reduced flufenacet efficacy was already observed.

RESULTS

In a screening of black‐grass populations from several European countries, most populations were controlled with the registered field rate of flufenacet. However, differences in the level of flufenacet sensitivity were observed and correlated with glutathione S‐transferase‐mediated enhanced flufenacet metabolism. The efficacy of the pre‐emergence herbicides pendimethalin, prosulfocarb, S‐metolachlor and pethoxamid, was also significantly decreased in populations with reduced flufenacet sensitivity. The use of flufenacet in mixtures with diflufenican, particularly in combination with flurtamone or metribuzin, however, significantly improved efficacy in less susceptible black‐grass populations.

CONCLUSIONS

In several populations of different European origins, reduced efficacy of flufenacet was observed due to enhanced metabolism. Although differences between populations were relatively small, best weed management practices (e.g. application of full dose rates and herbicide mixtures and wide crop rotations) should be applied to reduce selection pressure and prevent flufenacet resistance from further evolving. This is particularly important as flufenacet is one of the few still‐effective herbicides suitable for the control of multiple‐resistant A. myosuroides genotypes in Europe, whereas alternative pre‐emergence herbicides were less effective against multiple‐resistant A. myosuroides populations. © 2019 Society of Chemical Industry
Modeling of the Phytophthora capsici cellulose synthase 3 and its inhibitors activity assay
Authors: Wu Changcai , Zhao Jian , Li Zhikang , Liu Wanli , Mei Xiangdong , Ning Jun , She Dongmei
Published: March 2019

BACKGROUND

Phytophthora capsici is a devastating pathogen for crop. Cellulose synthase 3 (CesA3) is a target for many potential fungicides such as valinamide derivatives. However, the 3‐dimensional structure (3‐DS) of CesA3 in Phytophthora capsici was still unknown.

RESULTS

Here CesA3 protein sequence was retrieved from the NCBI protein sequence database We did the 3‐DS structural modeling for CesA3 and used molecular dynamics to optimize the model. The model was further validated by the Ramachandran plot in PROCHECK program. Two series of new valinamide compound were synthesized and tested for its biological activity. The docking data obtained by the model perfectly matched with the biometric data, indicating that the model is valid. Moreover, docking study data revealed the mechanism of action of inhibitors on target enzymes.

CONCLUSION

The 3‐DS structural model was analyzed from the perspective of the biocide receptor, the structure of the target protein and the mechanism of action of the compound. It provides a new perspective for the design of new fungicides. © 2019 Society of Chemical Industry
Migration in China: A cohort approach to understanding past and future trends
Authors: Bernard Aude , Bell Martin , Zhu Yu
Published: March 2019

Internal migration trends in China are well documented, but existing studies rely almost exclusively on period measures applied to cross‐sectional data. To examine long‐term trends, this paper adopts a cohort perspective and analyses migration levels and patterns and reasons for moving for cohorts born between 1935 and 1974. It applies a series of newly developed cohort measures to nationally representative migration histories retrospectively collected as part of the China Health and Retirement Longitudinal Study in 2014. It then develops cohort projections of migration from birth to age 60 for cohorts born between 1955 and 1994. The results show modest but rising levels of migration underpinned by a reduction in lifetime immobility and a rise in repeat movement, largely caused by an upswing in employment‐related moves and return migration. Cohort analysis reveals more stable trends than period measures, while showing significant sex differentials that have persisted across successive cohorts.