bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on the impact of three different quaternary methyl ammonium cartridges on the radiosynthetic yields of [18F]fluoromethyl tosylate
Authors: Stimson Damion H.R. , Qiao Zheng , Reutens David C. , Venkatachalam Taracad K. , Bhalla Rajiv
Published: June 2019

Our recent investigations for the radiosynthesis of [18F]fluoromethyl tosylate have highlighted that choice of quaternary methyl ammonium (QMA) cartridge used during the radiosynthesis can significantly impact the radiochemical yields. Often the details of the QMA cartridge used in fluourine‐18 syntheses are not fully described. However, our studies demonstrate that the type, the size, and nature (method by which it has been conditioned) of the QMA cartridge used during the radiosynthesis can make a significant impact in the labelling efficiency. This paper investigates the use of three QMA cartridges and demonstrates that radiochemical yield (decay corrected) of [18F]fluoromethyl tosylate can increase from 46% to 60% by simply changing the QMA cartridge (and leaving all other reagents and labelling conditions exactly the same). These learnings may be applied to improve the radiochemical yields of a number of [18F]‐fluorinated tracers (and synthons), where the labelling step is base‐sensitive to increase the radiochemical yield, thereby significantly benefiting the radiochemistry and nuclear medicine community. This paper also highlights the necessity of the radiochemistry community to ensure the details of QMA cartridges used in fluorine‐18 chemistry are fully and accurately described, since this will improve the translation of radiochemical methods from one laboratory to another.
Impacts of dietary microalgae (Schizochytrium JB5) on growth performance, blood profiles, apparent total tract digestibility, and ileal nutrient digestibility in weaning pigs
Authors: Kibria Sumya , Kim In Ho
Published: June 2019

BACKGROUND

Microalgae can serve as an alternative to animal feed additives or supplements in the diet of weaning pigs, to increase their potential and performance. Two experiments were conducted with three dietary treatments: CON (basal diet), MA1 (basal diet + 0.5% microalgae), and MA2 (basal diet + 1.0% microalgae). In Experiment 1, 150 crossbred weaning pigs were used in a 5‐week experiment. In Experiment 2, 15 cannulated barrows were used.

The objective of this study was to determine the effects of dietary supplementation of Schizochytrium microalgae on growth performance, blood profiles, apparent total tract digestibility, and ileal nutrient digestibility in weaning pigs.

RESULTS

In Experiment 1, pigs fed with MA2 had higher growth (P < 0.05) than pigs fed with MA1 from day 8 to day 21 but the experimental result showed no significant effects (P > 0.05) on growth performance, white blood cell, total cholesterol, and triglyceride among the treatments. However, lymphocytes (%) of pigs fed with MA1 and MA2 diets were significantly higher (P < 0.05) than those of pigs fed with a CON diet at day 35. In Experiment 2, the apparent total tract digestibility and ileal nutrient digestibility of dry matter and nitrogen were higher (P < 0.05) in pigs fed with MA1 and MA2 than in those fed with a CON diet.

CONCLUSION

Dietary microalgae supplementation had more dramatic and beneficial effects on nutrient digestibility than a CON diet. It also increased lymphocyte concentration but had no significant effect on growth performance in weaning pigs. © 2019 Society of Chemical Industry
The sharing and management of managers' knowledge: A structured literature review
Authors: Ouédraogo Miché , Rinfret Natalie
Published: June 2019

The management and sharing of managers' knowledge constitute vital components of organizational success and performance. A range of existing studies on managerial knowledge has analyzed various aspects of knowledge sharing and management on a patchwork basis. With future research developments in mind, some stock‐taking of the current body of research studies should now be undertaken for the purpose of obtaining a clearer understanding of how managerial knowledge is and could be shared and managed. Specifically, this study strives to reply to three questions: (1) What is the status of the development of literature concerning managers' knowledge? (2) What are the various conceptualizations of managers' knowledge and of its sharing and management? (3) What are the main determinants of the sharing and management of managers' knowledge that have been identified in the literature?

A structured literature review method was used to code and analyze 57 studies published between 1997 and 2016.

The results show that 128 authors produced an average of 3.2 publications per year, offering an abundance of conceptualizations of managers' knowledge and of its sharing and management. Several individual and organizational determinants of managerial knowledge sharing and management were identified in our review. The various findings provide a basis for orienting future research in this field.
Accuracy of clinical scoring tools for the diagnosis of pediatric obstructive sleep apnea
Authors: Patel Anant P. , Meghji Sheneen , Phillips John S.
Published: June 2019

Objectives

To assess the diagnostic test accuracy of questionnaire and clinical examination‐based scoring tools in the diagnosis of pediatric obstructive sleep apnea (OSA).

Methods

A comprehensive literature search was performed to identify studies published from 1960 to 2018 that evaluated the accuracy of clinical scoring tools in the diagnosis of pediatric OSA. Studies that did not include attended polysomnography as a reference standard were excluded. The study populations were children under 18 years old without craniofacial abnormalities, congenital syndromes, or other complex medical conditions. Outcomes measures were diagnostic test accuracy (DTA) statistics including sensitivity, specificity, and area under the curve (AUC) from receiver operating characteristic curve analysis.

Results

Fifteen different scoring tools were identified. Authors chose different polysomnographic criteria to diagnose OSA. Four of the tools had undergone multiple DTA studies by different authors (OSA Score, Sleep‐Related Breathing Disorder [SRBD] scale, Severity Score, and OSA‐18). The Pediatric Sleep Questionnaire SRBD scale, which is widely used, has a sensitivity of 71% to 84% in included studies, but specificity as low as 13% and a low AUC of 0.57‐0.69, indicating poor diagnostic accuracy. None of the 15 scoring tools performed well enough to be considered accurate diagnostic tests for pediatric OSA.

Conclusions

A well‐designed questionnaire can provide crucial information on the impact of sleep‐disordered breathing on a child's physical and psychological health, which may not be adequately reflected in objective polysomnography outcomes measures. However, DTA results indicate that published clinical scoring tools do not accurately predict a diagnosis of pediatric OSA as defined by polysomnography outcome measures. Laryngoscope, 130:1034–1043, 2020
9,10‐Dithio/oxo‐Anthracene as a Novel Photosensitizer for Photoinitiator Systems in Photoresists
Authors: Lei Jing , Akitoshi Tanimoto , Katou Sadaki , Murakami Yasuharu , Yin Jie , Jiang Xuesong
Published: June 2019

Five novel 9,10‐dithio/oxo‐anthracenes (ANs) are synthesized, which can be used as efficient photosensitizers for a biimidazole (BCIM) photoinitiator system in dry film photoresists. The potential of ANs as photosensitizer for BCIM is investigated in detail through fluorescence spectra, ESR, and real‐time FT‐IR. The resulting ANs possess strong absorption in the near UV–vis range from 350 to 450 nm with high molar extinction coefficients. The thiol ether and phenyl groups can make UV–vis absorption to be enhanced and red‐shifted significantly. Upon irradiation with 365 or 450 nm of light, BCIM can be photosensitized by ANs and can initiate photopolymerization of acrylate monomer (HDDA) efficiently. The dry film photoresist containing AN@BCIM photoinitiator system can form fine micro‐patterns with high resolution through 405 nm laser direct‐writing photolithography.
High‐Strength, Rapidly Self‐Recoverable, and Antifatigue Nano‐SiO2/Poly(Acrylamide–Lauryl Methacrylate) Composite Hydrogels
Authors: Pan Shenxin , Xia Meng , Fang Zhengping , Fu Jing , Wu Yuting , Sun Zhengguang , Zhang Yuhong , He Peixin
Published: June 2019

Creating load‐bearing hydrogels with superior mechanical strength and toughness is of vital importance for promoting the development of polymer hydrogels toward practical applications. Herein, a type of composite hydrogel is facilely fabricated employing simple and effective UV irradiation one‐pot method by introducing cheap and available nanosilica sol into hydrophobic association poly(acrylamide–lauryl methacrylate) (HAPAM gels). Composite hydrogels exhibit enhanced mechanical strength (compression stress reaching 4.4 MPa) and toughness (compression hysteresis energy achieved is 151.15 kJ m−3) compared to HAPAM gels. Composite hydrogels also demonstrate rapid self‐recovery behavior (95.91% stress recovery and 92.19% hysteresis energy recovery after restoration for 15 min, respectively) and favorable fatigue‐resistant ability without the help of external stimuli at room temperature based on the cyclic loading–unloading compression measurements. The simple and effective design strategy may help the development of hydrogel materials toward practical applications for soft sensors, tissue engineering, and actuators.
Functionalized Graphene Oxide Based on Hydrogen‐Bonding Interaction in Water: Preparation and Flame‐Retardation on Epoxy Resin
Authors: Zhao Bin , Liu Peng‐Wei , Liu Dong‐Yue , Kolibaba Thomas J. , Zhang Cong‐Yun , Liu Yan‐Ting , Liu Ya‐Qing
Published: June 2019

A novel functionalized graphene oxide (f‐GO) decorated with phosphorus/nitrogen (P/N)‐containing molecules is fabricated using a facile water‐based procedure. The chemical structure and micro‐morphology are well characterized by a combination of experimental and theoretical methods. Reactive force field‐based molecular dynamics simulations reveal at the atomic level that the GO sheets are successfully functionalized with P‐N flame‐retardant molecules by means of hydrogen bonds. Subsequently, f‐GO with extremely low loading is introduced into epoxy resin (EP) for reducing its flammability. Thermogravimetric analysis suggests that f‐GO significantly reduces the maximum mass loss rate of EP and enhances the char‐yield during heating. Combined with the results of a microscale combustion calorimeter and limiting oxygen index, EP/f‐GO2 shows better flame retardancy than the other nanocomposites. Furthermore, the presence of 2 wt% f‐GO substantially reduces the fire hazard of EP, resulting in 29.3% decline in the peak heat release rate, as well as 73% and 65% reduction in total smoke production and rate of smoke release, respectively, according to cone calorimetric tests. Based on the analyses of the char layers, f‐GO is determined to promote the formation of a more protective phosphorus‐containing char barrier for EP during combustion, indicating an effective condensed phase flame‐retardant mechanism.
SNCAandmTORPathway Single Nucleotide Polymorphisms Interact to Modulate the Age at Onset of Parkinson's Disease
Authors: Fernández‐Santiago Rubén , Martín‐Flores Núria , Antonelli Francesca , Cerquera Catalina , Moreno Verónica , Bandres‐Ciga Sara , Manduchi Elisabetta , Tolosa Eduard , Singleton Andrew B. , Moore Jason H. ,   The International Parkinson's Disease Genomics Consortium, Martí María‐Josep , Ezquerra Mario , Malagelada Cristina
Published: June 2019

Background

Single nucleotide polymorphisms (SNPs) in the α‐synuclein (SNCA) gene are associated with differential risk and age at onset (AAO) of both idiopathic and Leucine‐rich repeat kinase 2 (LRRK2)‐associated Parkinson's disease (PD). Yet potential combinatory or synergistic effects among several modulatory SNPs for PD risk or AAO remain largely underexplored.

Objectives

The mechanistic target of rapamycin (mTOR) signaling pathway is functionally impaired in PD. Here we explored whether SNPs in themTORpathway, alone or by epistatic interaction with known susceptibility factors, can modulate PD risk and AAO.

Methods

Based on functional relevance, we selected a total of 64 SNPs mapping to a total of 57 genes from themTORpathway and genotyped a discovery series cohort encompassing 898 PD patients and 921 controls. As a replication series, we screened 4170 PD and 3014 controls available from the International Parkinson's Disease Genomics Consortium.

Results

In the discovery series cohort, we found a 4‐loci interaction involvingSTK11rs8111699,FCHSD1rs456998,GSK3Brs1732170, andSNCArs356219, which was associated with an increased risk of PD (odds ratio = 2.59,P< .001). In addition, we also found a 3‐loci epistatic combination ofRPTORrs11868112 andRPS6KA2rs6456121 withSNCArs356219, which was associated (odds ratio = 2.89;P< .0001) with differential AAO. The latter was further validated (odds ratio = 1.56;P= 0.046‐0.047) in the International Parkinson's Disease Genomics Consortium cohort.

Conclusions

These findings indicate that genetic variability in themTORpathway contributes toSNCAeffects in a nonlinear epistatic manner to modulate differential AAO in PD, unraveling the contribution of this cascade in the pathogenesis of the disease. © 2019 International Parkinson and Movement Disorder Society
Association of MAPT H1 subhaplotypes with neuropathology of lewy body disease
Authors: Heckman Michael G. , Kasanuki Koji , Brennan Rebecca R. , Labbé Catherine , Vargas Emily R. , Soto Alexandra I. , Murray Melissa E. , Koga Shunsuke , Dickson Dennis W. , Ross Owen A.
Published: June 2019

Background

Genetic variation at the microtubule‐associated protein tau locus is associated with clinical parkinsonism. However, it is unclear as to whether microtubule‐associated protein tau H1 subhaplotypes are associated with the burden of neuropathological features of Lewy body disease.

Objectives

To evaluate associations of microtubule‐associated protein tau haplotypes with severity of Lewy body pathology and markers of SN neuronal loss in Lewy body disease cases.

Methods

Five hundred eighty‐five autopsy‐confirmed Lewy body disease cases were included. Six microtubule‐associated protein tau variants (rs1467967, rs242557, rs3785883, rs2471738, rs8070723, and rs7521) were genotyped to define common microtubule‐associated protein tau haplotypes. Lewy body counts were measured in five cortical regions. Ventrolateral and medial SN neuronal loss were assessed semiquantitatively. Nigrostriatal dopaminergic degeneration was quantified by image analysis of tyrosine hydroxylase immunoreactivity in the dorsolateral and ventromedial putamen.

Results

The common microtubule‐associated protein tau H2 haplotype did not show a strong effect on pathological burden in Lewy body disease. The rare H1j haplotype (1.3%) was significantly associated with a lower dorsolateral putaminal tyrosine hydroxylase immunoreactivity (and therefore greater dopaminergic degeneration) compared to other microtubule‐associated protein tau haplotypes (P = 0.0016). Microtubule‐associated protein tau H1j was also nominally (P ≤ 0.05) associated with a lower ventromedial putaminal tyrosine hydroxylase immunoreactivity (P = 0.010), but this did not survive multiple testing correction. Other nominally significant associations between microtubule‐associated protein tau H1 subhaplotypes and neuropathological outcomes were observed.

Conclusions

A rare microtubule‐associated protein tau H1 subhaplotype (H1j) may be associated with more severe putaminal dopaminergic degeneration in Lewy body disease cases. Microtubule‐associated protein tau H1j has been associated previously with an increased risk of PD, and therefore our exploratory findings provide insight into the mechanism by which H1j modulates PD risk. © 2019 International Parkinson and Movement Disorder Society
An umbrella‐shaped broadband circularly polarized antenna with wide beamwidth for global navigation satellite systems applications
Authors: Yan Yang‐Dong , Jiao Yong‐Chang , Weng Zibin , Zhang Chi
Published: June 2019

A novel umbrella‐shaped wideband circular polarization (CP) antenna with a wide half‐power beamwidth (HPBW) and a wide axial ratio (AR) bandwidth is proposed in this article. Two pairs of symmetrical patch dipoles are attached to the surface of an umbrella‐shaped substrate to broaden both the impedance bandwidth (IBW) and the HPBW. A parasitic metallic ring is located immediately above the umbrella substrate to provide further enhancement of the HPBW. Each patch dipole is excited via a coaxial line, while a conductor balun with length of λ0/4 (where λ0 is the wavelength of the center frequency) is introduced to obtain a feeding balance. Measurement results indicate that the proposed antenna has a −10 dB IBW of 71.3% (from 1.03 to 2.17 GHz), and a 3 dB AR bandwidth of 55.6% (from 1.13 to 2.0 GHz). Additionally, an HPBW of more than 110° is obtained over the whole CP bandwidth, 48.2% of which has an HPBW of more than 120°. The antenna has dimensions of 100 × 100 × 28 mm3, which corresponds to (0.52 × 0.52 × 0.14)λ03.
Amyotrophic lateral sclerosis: Origins traced to impaired balance between neural excitation and inhibition in the neonatal period
Authors: Kiernan Matthew C. , Ziemann Ulf , Eisen Andrew
Published: June 2019

Amyotrophic lateral sclerosis (ALS) is an adult onset disease but with an increasingly recognized preclinical prodrome. A wide spectrum of investigative approaches has identified loss of inhibitory function at the heart of ALS. In developing an explanation for the onset of ALS, it remains a consideration that ALS has its origins in neonatal derangement of the γ‐aminobutyric acid (GABA)‐ergic system, with delayed conversion from excitatory to mature inhibitory GABA and impaired excitation/inhibition balance. If this is so, the resulting chronic excitotoxicity could marginalize cortical network functioning very early in life, laying the path for neurodegeneration. The possibility that adult‐onset neurodegenerative conditions might have their roots in early developmental derangements is worthy of consideration, particularly in relation to current models of disease pathogenesis. Unraveling the very early molecular events will be crucial in developing a better understanding of ALS and other adult neurodegenerative disorders. Muscle Nerve, 2019
Uniformly convergent novel finite difference methods for singularly perturbed reaction–diffusion equations
Authors: He Xuefei , Wang Kun
Published: June 2019

In this paper, we construct a kind of novel finite difference (NFD) method for solving singularly perturbed reaction–diffusion problems. Different from directly truncating the high‐order derivative terms of the Taylor's series in the traditional finite difference method, we rearrange the Taylor's expansion in a more elaborate way based on the original equation to develop the NFD scheme for 1D problems. It is proved that this approach not only can highly improve the calculation accuracy but also is uniformly convergent. Then, applying alternating direction implicit technique, the newly deduced schemes are extended to 2D equations, and the uniform error estimation based on Shishkin mesh is derived, too. Finally, numerical experiments are presented to verify the high computational accuracy and theoretical prediction.
The value of echocardiography and Doppler in the prediction of fetal demise after laser coagulation for TTTS: A systematic review and meta‐analysis
Authors: Gijtenbeek Manon , Eschbach Sanne J. , Middeldorp Johanna M. , Klumper Frans J.C.M. , Slaghekke Femke , Oepkes Dick , Haak Monique C.
Published: June 2019

This study aimed to investigate the value of echocardiography and Doppler before fetoscopic laser coagulation for twin‐twin transfusion syndrome (TTTS) in the prediction of intrauterine fetal demise (IUFD). We performed a systematic review and meta‐analysis to compare preoperative parameters between fetuses with and without demise after laser surgery. Eighteen studies were included. Recipient twins have an increased risk of demise in case of preoperative absent/reversed flow (A/REDF) in the umbilical artery (odds ratio [OR] 2.76, 95% confidence interval [CI], 1.78‐4.28), absent or reversed a‐wave in the ductus venosus (OR 2.32, 95% CI, 1.70‐3.16), or a middle cerebral artery peak systolic velocity > 1.5 multiples of the median (MoM) (OR 7.59, 95% CI, 2.56‐22.46). In donors, only A/REDF in the umbilical artery (OR 3.40, 95% CI, 2.68‐4.32) and absent or reversed a‐wave in the ductus venosus (OR 1.66, 95% CI, 1.12‐2.47) were associated with IUFD. No association was found between donor‐IUFD and preoperative myocardial performance index (MPI). Two studies found an association between abnormal MPI and recipient demise. With this study, we have identified a set of preoperative Doppler parameters predictive of fetal demise after laser surgery. More research is needed to assess the utility of preoperative echocardiographic parameters such as the MPI in predicting IUFD.
Impact of a population‐based asthma management program in France (Sophia Asthme): A matched controlled before‐and‐after quasi‐experimental study using the French health insurance database (SNDS)
Authors: Dib Fadia , de Rycke Yann , Guillo Sylvie , Lafourcade Alexandre , Raherison Chantal , Taillé Camille , Tubach Florence
Published: June 2019

Purpose

Sophia Asthme (SA) is a chronic disease management program of the French national health insurance for adult patients with asthma. We evaluated the early impact of this intervention.

Methods

We conducted a matched controlled, before‐and‐after quasi‐experimental study within the French Health Insurance Database (Système National Des Données de Santé [SNDS]). The SA program was implemented in a set of 18 Départements in France and targeted 18‐ to 44‐year‐old subjects, with at least two reimbursement dates for asthma drug therapy during the 12‐month period prior to program targeting. Change in outcomes was assessed from the “before program” period (January‐December 2014) to the “after program implementation” period (March 2015‐February 2016) in the program group (eligible to SA program in the 18 Départements) and in the matched controlled group. The main outcome measure was the before‐after change in proportion of subjects with a controllers/(controllers+relievers) ratio greater than 50%.

Results

Of the 99 578 subjects of the program group, 9225 (9.3%) actually participated in SA program. The program had no significant impact on the proportion of subjects with a ratio greater than 50%. However, subjects exposed to SA program were significantly more likely to be dispensed controller medications (OR = 1.04; 95% CI, 1.01‐1.07) and to sustain their use of these medications (OR = 1.08; 95% CI, 1.05‐1.12).

Conclusion

We did not demonstrate any significant impact of the program on the primary outcome. The modest yet encouraging findings of this early evaluation suggest the need for reformulation of the program and its evaluation.
Central precocious puberty as a prelude to hypogonadism in a patient with Klinefelter syndrome
Authors: Gong Chunxiu , Li Lele , Chen Jiahui , Li Wenjing
Published: June 2019

Introduction

Incomplete pubertal development is a common phenomenon found in patients with Klinefelter syndrome (KFS). KFS combined with central precocious puberty (CPP) rarely occurs. We herein report a rare case of KFS with CPP and review several studies to determine the possible mechanism underlying this condition.

Case presentation

An 8‐year, 5‐month‐old male patient was admitted to our hospital because of enlargement of the penis and small testes. Laboratory evaluation revealed high luteinizing hormone and follicle‐stimulating hormone levels, a high testosterone level, and the 48,XXYY karyotype. He was treated with triptorelin. One year later, the patient's testosterone level decreased and pubertal arrest occurred.

Conclusion

The literature review in this study showed that the occurrence of hypogonadism combined with CPP is not unique to patients with KFS; it has also been reported in individuals with Turner syndrome, adrenal hypoplasia congenita, and other diseases. Such individuals share common features including partial hypogonadism and a normal hypothalamic‐pituitary‐gonadal axis. CPP is considered a prelude to hypogonadism, and treatment with a gonadotropin‐releasing hormone agonist may prevent gonadal failure.
Influence of thermal annealing on mechanical properties andin vitrodegradation of poly(p‐dioxanone)
Authors: Zhang Jian‐Feng , Jones Scott , Wang Donghui , Wood Andrew , Washington Tommy , Acreman Kevin , Cuevas Brian , Karau Andreas
Published: June 2019

Poly(p‐dioxanone) (PDO), a versatile poly(ester‐ether), has been used for a variety of biomedical applications. Functional performance of this semicrystalline polymer heavily relies on its crystallinity and crystalline behavior. Upon extended exposure to heat above the glass transition temperature and below the melting temperature, PDO undergoes thermal annealing. Isothermal studies at elevated temperatures utilizing a differential scanning calorimeter were performed in order to determine the most appropriate conditions to anneal the polymer. Of the investigated mechanical properties, yield strength and elastic modulus were significantly improved with annealing. This improvement over nonannealed samples was also observed with samples subjected to phosphate‐buffered saline (PBS) solution at 37°C for 2 weeks. After 1 month continuous immersion in PBS solution, the PDO became brittle with deteriorated elongation at break but maintained yield strength and modulus. At 2 months, all specimens exhibited cracks on the surface and a complete loss of mechanical strength. The enhanced yield strength by thermal annealing creates more opportunities for PDO in medical device implants particularly in applications involving soft tissue repair and hemostasis. POLYM. ENG. SCI., 59:1701–1709 2019. © 2019 Society of Plastics Engineers
Personality disorder co‐morbidity in primary care ‘Improving Access to Psychological Therapy’ services: A qualitative study exploring professionals' perspectives of working with this patient group
Authors: Lamph Gary , Baker John , Dickinson Tommy , Lovell Karina
Published: June 2019

A high prevalence of people present to ‘Improving Access to Psychological Therapies’ (IAPT) in England with common mental health disorders and co‐morbid personality disorder. This group have suboptimal treatment outcomes in IAPT. Whilst new short‐term treatment approaches are advocated, no solutions or guidance have been provided. This qualitative study explored IAPT health‐care professional (N = 28) perspectives of working with people who present to IAPT with co‐morbid personality disorder. Individual semi‐structured interviews were digitally recorded, transcribed verbatim and analysed using a framework analysis approach. Results identified a lack of skills and confidence in working with this patient group, restrictive service constraints and a treatment gap between the interface of primary and secondary services. Insight into acceptable adaptions to practice are identified that have transferable utility to a wider international audience who can identify people outside of specialist mental health services with common mental health disorders and co‐morbid personality disorder traits. © 2019 John Wiley & Sons, Ltd.
Should engineers have more influence on safety? A view from a member of the United States Chemical Safety Board
Authors: Engler Rick
Published: June 2019

Major chemical incidents continue at industrial facilities in the United States. More effective arguments for a “business case” for safety are necessary, but not sufficient, to achieve prevention. Findings of the U.S. Chemical Safety and Hazard Investigation Board from its investigations at two oil refineries suggest that greater authority for engineers and safety professionals is a critical requirement to prevent future incidents. Engineers and safety professionals should have greater influence on process design, commissioning, maintenance, and capital and operating budgets. They should be part of the firm's highest level of management and Board of Directors. Engineers should also have the ability to make process hazard analysis an ongoing process and to directly communicate hazards and needed safeguards to senior corporate leaders.
Observation of the Stacking Faults in In0.53Ga0.47As by Electron Channeling Contrast Imaging
Authors: Hsu Po-Chun (Brent) , Han Han , Simoen Eddy , Merckling Clement , Eneman Geert , Mols Yves , Collaert Nadine , Heyns Marc
Published: June 2019

The observation and interpretation of Frank stacking faults, Shockley stacking faults, Lomer dislocations, and 60° misfit dislocations, which have similar line shapes in the (001) In0.53Ga0.47As crystalline surface, are performed with the electron channeling contrast imaging (ECCI) technique. To minimize the backscattered electron (BSE) contrast that resulted from the surface morphology, a relatively flat region is first selected and compared with an atomic force microscopy (AFM) image and then, subsequently, examining ECCI with transmission electron microscopy (TEM)‐like invisibility criteria. By orthogonally choosing the diffraction vector g between (220) and (2‐20), misfit dislocations seem to be always visible but partially faint in the g parallel to the line direction on the surface. With respect to the image contrast, Frank stacking faults and Lomer dislocations are likely to be completely invisible for parallel g. The criteria are further confirmed by cross‐sectional TEM analysis, which shows a preferred homogeneous surface nucleation.
System‐level reliability sensitivity analysis by using weighted average simulation method
Authors: Rashki Mohsen , Azhdary Moghaddam Mehdi , Miri Mahmoud
Published: June 2019

In addition to reliability analysis, investigation of the uncertainties' effect on the safety of structures can be regarded as one of the great concerns in engineering fields. The present study provides an efficient perturbation‐based reliability sensitivity analysis approach based on weighted average simulation method (WASM) to attain uncertainties effects on the structures safety. Without asking additional samplings and/or requiring to function derivation (that is necessary in score function method), the proposed approach simultaneously uses the finite difference and weight flexibility feature of WASM to estimate the parameter sensitivities of a reliability problem. The proposed method has also been successfully applied to the improved version of WASM to obtain reliability based sensitivity results with very few samples. The accuracy and efficiency of the proposed method is examined by solving five analytical and engineering examples with highly nonlinear performance functions and system‐level reliability problems. For each example, results are compared with those obtained by Monte Carlo simulation and common reliability methods. It is shown that the method is capable of solving real world system‐level engineering problems efficiently and accurately.
Exertion during a hypoxia altitude simulation test helps identify potential cardiac decompensation
Authors: Seccombe Leigh , Peters Matthew , Farah Claude
Published: June 2019

A 64‐year‐old female with a history of chronic thromboembolic pulmonary arterial hypertension (CTEPH), moderate airway obstruction (forced expiratory volume in 1 second (FEV1) 58% predicted), and resting oxygen saturation below the normal range (SaO2 94%) underwent a hypoxic challenge test (HCT) to determine suitability for long‐haul air travel. The HCT showed only a mild decrease in SaO2 (89% at 0.15 fraction of inspired oxygen (FIO2)) at rest. However, a HCT coupled with mild exercise at two metabolic equivalents demonstrated significant hypoxia (SpO2 77%) with worsening right ventricular impairment and an inability to increase cardiac output measured with echocardiography. The case highlights the importance of the evaluating cardiac and pulmonary reserve during hypoxic stress. Resting measures alone may not identify risk, and the addition of an exercise component was essential in this case.
Logics of affordability and worth: Gendered consumption in rural Uganda
Authors: Dolan Catherine , Gordon Claire , Steinfield Laurel , Hennegan Julie
Published: June 2019

This article explores logics of affordability and worth within rural Ugandan households. Through an analysis of how worth is ascribed to certain goods, from the morally ambiguous personal consumption of alcohol and beauty products to the “responsible” category of educational spending and sanitary pads, the article demonstrates how gender norms and anxieties are marked and sustained in the consumption practices of the household, constituting what is deemed necessary, affordable, and responsible. Moral obligation is differentially distributed between genders: women are deemed responsible for household expenditure, their personal consumption preferences constrained, whereas men are able to delimit a sphere of personal consumption separate from the household, with limited accountability to its moral requirements. The gendered nature of power relations is thus revealed both in the apportioning of moral duty and in the construction of affordability through which consumption is enabled.
Nano‐bio interface study between Fe content TiO2 nanoparticles and adenosine triphosphate biomolecules
Authors: Barkhade Tejal , Phatangare Ambadas , Dahiwale Shailendra , Mahapatra Santosh Kumar , Banerjee Indrani
Published: June 2019

The advent of nano‐biotechnology has inspired the interface interaction study between engineered nanoparticles (NPs) and biomolecules. The interaction between Fe content titanium dioxide (TiO2) NPs and adenosine triphosphate (ATP) biomolecules has been envisioned. The effect of Fe content in TiO2 matrix was studied using X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The increase in Fe content caused a decrease in particle size with change in morphology from spherical to one‐dimensional rod structure. The Fe incorporation in the TiO2 matrix reduced the transition temperature from anatase to rutile (A‐R) phase along with formation of haematite phase of iron oxide at 400°C. The interaction of Fe content TiO2 NPs with ATP molecule has been studied using spectroscopic method of Raman scattering and infrared vibration spectrum along with TEM. Fe content in TiO2 has enhanced the interaction efficiency of the NPs with ATP biomolecules. Raman spectroscopy confirms that the NPs interact strongly with nitrogen (N7) site in the adenine ring of ATP biomolecule. Engineering of Fe content TiO2 NP could successfully tune the coordination between metal oxide NPs with biomolecules, which could help in designing devices for biomedical applications.
Compositional and electrical properties of Cr, Nb, Cr/Nb, CrNbN, and CrN/NbN multilayers grown using the d.c. magnetron sputtering technique
Authors: Garzon‐Fontecha Angélica , Castillo Harvi , Escobar‐Rincón Daniel , Restrepo‐Parra Elisabeth , De La Cruz Wencel
Published: June 2019

Cr, Nb, Cr/Nb, CrNx, NbNx, CrNbN, and (CrN/NbN)n structures were produced on Si and glass substrates, using the d.c. magnetron sputtering technique. Compositional analysis, based on binding energies of Cr, Nb, and N, was carried out by means of X‐ray photoelectron spectroscopy (XPS). Through Auger electron spectroscopy (AES), depth profiles were obtained, allowing to demonstrate the multilayers production. Surface morphological characteristics, as roughness and grain size, were evaluated by atomic force microscopy (AFM), revealing very smooth surfaces, that is a consequence of the deposition parameters used in the synthetization experiments. Finally, for different configurations, conductivity measurements were carried out, revealing the influence of nitrogen content and temperature on electron transport. It was found that substoichiometric nitrides (CrN0.35 and NbN0.12) exhibited the highest conductivity, because the nitrogen atoms act as donor of electrons.
Recent advances in dual mode charge compensation for XPS analysis
Authors: Edwards Lee , Mack Paul , Morgan David J.
Published: June 2019

Dual mode charge compensation has been used successfully for many years to enable X‐ray photoelectron spectroscopy (XPS) analysis of a variety of insulating samples. This approach uses a combination of low energy electrons and argon to compensate for positive charge build‐up during irradiation by X‐rays. Whilst this method works with no detectable side effects in most cases, it was recently reported that the chemical bonding states of some Cr(VI) oxides may be modified by prolonged exposure to the flood source. In this work, we demonstrate successful dual mode charge compensation of CrO3 with no discernible sample modification from the flood source. Under the same flood source conditions, we extend the analysis to other systems known to undergo reduction and present charge compensated XPS data for V2O5 and a copper‐based metal‐organic framework (MOF) showing little or no modification from the flood source, even with prolonged exposure.
Desorption of carboxylates and phosphonates from galvanized steel: Towards greener lubricants
Authors: Hill Donald , Holliman Peter J. , Jones Eurig W. , McGettrick James , Worsley David A. , Appleman Marco , Chatterjee Pranesh
Published: June 2019

This paper studies the removal of chemisorbed carboxylates and phosphonates from TiO2‐coated galvanized steel using NaOH(aq). XPS and FTIR data show that NaOH(aq) is effective at desorbing these species and so is an alternative to gas phase processes (eg, plasma cleaning). Tribological investigations show that NaOH(aq)‐treated surfaces show reduced friction and wear, relative to the “as‐received” galvanized steel. This is ascribed to carbonate (present as an impurity in NaOH) that adsorbs to the surface of the substrate during NaOH(aq) immersion. Carbonate removal through sonication in water generates surfaces that show friction similar to “as‐received” galvanized steel. This work is useful in areas (eg, automotive manufacturing), where the effective removal of lubricants following tribological contact is key to subsequent paint adhesion.
Amberlyst‐15‐catalyzed Procedure for the Synthesis of Novel 2,4‐Dihydroxybenzoyl‐1,2,3‐triazoles and Molecular Modelling Studies for Hsp‐90 Inhibition
Authors: Gunduz Hande , Kumbaraci Volkan , Özkılıç Yılmaz , Tüzün Nurcan Ş. , Talinli Naciye
Published: June 2019

Novel 4‐and 5‐(2,4‐dihydroxybenzoyl) triazoles were prepared from o‐alkynoylresorcinols with by the cycloaddition reaction performed with metal free one step protocol using Bronsted acid Amberlyst‐15 as catalyst for the first time. This procedure enables the synthesis of triazoles bearing o,p‐dihydroxybenzoyl group without the need to protection of hydroxyl groups. Products were obtained in good to excellent yields and with the moderate regioisomeric ratios. In addition, Hsp90 inhibition activities of synthesized compounds were examined by molecular modelling studies and promising results were obtained.
Elucidation of Photoluminescence Blinking Mechanism and Multiexciton Dynamics in Hybrid Organic–Inorganic Perovskite Quantum Dots
Authors: Kim Taehee , Jung Seok Il , Ham Sujin , Chung Heejae , Kim Dongho
Published: June 2019

Halide perovskites (ABX3) have emerged as promising materials in the past decade owing to their superior photophysical properties, rendering them potential candidates as solar cells, light‐emitting diode displays, and lasing materials. To optimize their utilization into optoelectronic devices, fundamental understanding of the optical behaviors is necessary. To reveal the comprehensive structure–property relationship, CH3NH3PbBr3 (MAPbBr3) perovskite quantum dots (PQDs) of three different sizes are prepared by controlling the precipitation temperature. Photoluminescence (PL) blinking, a key process that governs the emission efficiency of the PQD materials, is investigated in detail by the time‐resolved spectroscopic measurements of individual dots. The nature of the generated species in the course of blinking events is identified, and the mechanism governing the PL blinking is studied as a function of PQD sizes. Further, the practical applicability of MAPbBr3 PQDs is assessed by studying the multiexciton dynamics under high photoexcitation intensity under which most of the display devices work. Ultrafast transient absorption spectroscopy helped in uncovering the volume‐dependent Auger recombination rates, which are further explored by comparing the early‐time transitions related to surface trap states and higher band states.
Growth of Ultraflat PbI2 Nanoflakes by Solvent Evaporation Suppression for High‐Performance UV Photodetectors
Authors: Xiao Han , Liang Tao , Xu Mingsheng
Published: June 2019

2D lead iodide (PbI2) is attracting great interest due to its great potential in the application of UV photodetectors. In this work, a facile solution‐based method is developed to synthesize ultraflat PbI2 nanoflakes for high‐performance UV photodetectors. By maintaining at proximate room temperature and adding an evaporation suppression solvent for slow‐rate crystal growth, high‐quality PbI2 nanoflakes with an ultraflat surface are obtained. The UV photodetectors based on 2D PbI2 nanoflakes exhibit a high photoresponsivity of 0.51 A W−1, a high detectivity of 4.0 × 1010 Jones, a high external quantum efficiency (EQE) of 168.9%, and a rapid response speed including a rise time of 14.1 ms and a decay time of 31.0 ms. The balanced and excellent photodetector performance of these devices paves the road for practical UV photodetection based on 2D PbI2 nanoflakes.
A study on the relationship between metabolism of Cyanobacteria and chemical oxygen demand in Dianchi Lake, China
Authors: He Jia , Zhang Ying , Wu Xue , Yang Yan , Xu Xiaomei , Zheng Binghui , Deng Weiming , Shao Zhi , Lu Lu , Wang Li , Zhou Hongbin
Published: June 2019

Recent increases in concentrations of chemical oxygen demand (COD‐Cr) in Dianchi Lake, China, is an important factor affecting its water quality. Large volumes of cyanobacteria algae have also been recorded in this lake; its growth, distribution and metabolism are believed to directly or indirectly affect water quality. The relationship between metabolism of cyanobacteria and COD‐Cr in Dianchi Lake, and the causes of this relationship, are examined in this study. Results show that the increase of COD‐Cr concentration is closely related to the metabolism of algae, and that organic substances containing nitrogen and sugars, produced by metabolism, contribute to an increase of COD‐Cr to a certain extent. The characteristics of fluorescence spectra of dissolved organic matter (DOM) in the Waihai area of Dianchi Lake are similar to those of algae culture water, and their dominant substances are protein‐like substances. Algae release organic substances into water during its growth cycle and extracellular organic substances are mainly released during its normal growth and metabolism stages. Once algae cells enter the decline stage, internal organic matter is released during the dying and decomposition stages, resulting in a distinct increase of COD‐Cr. A high concentration of organic matter is present in Dianchi Lake sediments, dominated by native organic matter predominantly derived from aquatic plants and plankton. This finding indicates a potential long‐term risk of organic pollutants being released from dead algae cells into the lake.

Practitioner points

There is a distinct positive correlation between COD‐Cr and Chl‐a concentration in Dianchi Lake.

Organic substances containing nitrogen and sugars produced by algae metabolism contributed to COD‐Cr.

The cells die and decompose organic matter content in the water substantially increases, resulting in a distinct increase of COD‐Cr.

Weight >20 kDa are mainly released into the water body during the decomposition of algae cells after mortality.

Organic matter content in the water substantially increases, resulting in a distinct increase of COD‐Cr.
Further evidence for the weak gravity — cosmic censorship connection
Authors: Horowitz Gary T. , Santos Jorge E.
Published: June 2019

Abstract

We have recently shown that a class of counterexamples to (weak) cosmic censorship in anti-de Sitter spacetime is removed if the weak gravity conjecture holds. Surprisingly, the minimum value of the charge to mass ratio necessary to preserve cosmic censorship is precisely the weak gravity bound. To further explore this mysterious connection, we investigate two generalizations: adding a dilaton or an additional Maxwell field. Analogous counterexamples to cosmic censorship are found in these theories if there is no charged matter. Even though the weak gravity bound is modified, we show that in each case it is sufficient to remove these counterexamples. In most cases it is also necessary.
On the positive geometry of conformal field theory
Authors: Arkani-Hamed Nima , Huang Yu-tin , Shao Shu-Heng
Published: June 2019

Abstract

It has long been clear that the conformal bootstrap is associated with a rich geometry. In this paper we undertake a systematic exploration of this geometric structure as an object of study in its own right. We study conformal blocks for the minimal SL(2, R) symmetry present in conformal field theories in all dimensions. Unitarity demands that the Taylor coefficients of the four-point function lie inside a polytope U determined by the operator spectrum, while crossing demands they lie on a plane X. The conformal bootstrap is then geometrically interpreted as demanding a non-empty intersection of U ∩ X. We find that the conformal blocks enjoy a surprising positive determinant property. This implies that U is an example of a famous polytope — the cyclic polytope. The face structure of cyclic polytopes is completely understood. This lets us fully characterize the intersection U∩X by a simple combinatorial rule, leading to a number of new exact statements about the spectrum and four-point function in any conformal field theory.
Flexibility and visibility
Authors: Vedeler Janikke Solstad , Anvik Cecilie Høj
Published: June 2019

Among the disabled workforce, many are engaged in part-time work. However, research regarding the relationship between disability and part-time work has only partially elucidated how people with disabilities who are in receipt of partial or graded disability pensions perceive and handle the combination of part-time work with their pension payments. This article addresses the narrated strategies employed by people with disabilities in managing part-time employment, drawing on interview data from 10 Norwegian citizens who worked part-time in addition to receiving a graded disability pension. The findings illustrate that flexibility and visibility are specific strategies that our informants implement when health issues and reduced working hours result in weakened connections to the workplace. The article demonstrates how the discourses around paid employment facilitate these strategies. By providing insight into people’s narrated experiences of engaging in part-time work with disabilities, the article offers significant recommendations into the conditions necessary for people with disabilities to remain employed while also in receipt of graded disability pensions.