bluuebunny/crossref_metadata_2025 huggingface dataset:
Targeting virulence factors as an antimicrobial approach: Pigment inhibitors
Authors: Ni Shuaishuai , Li Baoli , Xu Yixiang , Mao Fei , Li Xiaokang , Lan Lefu , Zhu Jin , Li Jian
Published: July 2019

The fascinating and dangerous colored pathogens contain unique chemically pigmented molecules, which give varied and efficient assistance as virulence factors to the crucial reproduction and growth of microbes. Therefore, multiple novel strategies and inhibitors have been developed in recent years that target virulence factor pigments. However, despite the importance and significance of this topic, it has not yet been comprehensively reviewed. Moreover, research groups around the world have made successful progress against antibacterial infections by targeting pigment production, including our serial works on the discovery of CrtN inhibitors against staphyloxanthin production in Staphylococcus aureus. On the basis of the previous achievements and recent progress of our group in this field, this article will be the first comprehensive review of pigment inhibitors against colored pathogens, especially S. aureus infections, and this article includes design strategies, representative case studies, advantages, limitations, and perspectives to guide future research.
Ultrasound elastography for the evaluation of peripheral nerves: A systematic review
Authors: Wee Tze Chao , Simon Neil G.
Published: July 2019

Peripheral nerve disorders are commonly encountered in clinical practice. Electrodiagnostic studies remain the cornerstone of the evaluation of nerve disorders. More recently, ultrasound has played an increasing complementary role in the neuromuscular clinic. Ultrasound elastography is a technique that measures the elastic properties of tissues. Given the histological changes that occur in diseased peripheral nerves, nerve ultrasound elastography has been explored as a noninvasive way to evaluate changes in nerve tissue composition. Studies to date suggest that nerve stiffness tends to increase in the setting of peripheral neuropathy, regardless of etiology, consistent with loss of more compliant myelin, and replacement with connective tissue. The aim of this systematic review is to summarize the current literature on the use of ultrasound elastography in the evaluation of peripheral neuropathy. Limitations of ultrasound elastography and gaps in current literature are discussed, and prospects for future clinical and research applications are raised.
Effects of horticultural therapy: Perspectives of frail and pre‐frail older nursing home residents
Authors: Lo Shirley K. L. , Lam Winsome Y. Y. , Kwan Rick Y. C. , Tse Mimi M. Y. , Lau Jordan K. H. , Lai Claudia K. Y.
Published: July 2019

Aim

The aim of the study was to explore the perceptions and experiences of a group of frail and/or pre‐frail older nursing home residents in relation to horticultural therapy.

Method

A total of 22 frail/pre‐frail residents were interviewed. A qualitative content analysis approach was adopted to interpret the data from four nursing homes.

Results

Four main themes were identified: (a) “Horticultural therapy is an enjoyable activity and a good pastime in nursing home life”; (b) “Joining the programme made me happier”; (c) “Horticultural activities facilitated socialization among the residents”; and (4) “Not much mention was made of the programme by the staff outside the sessions.”

Conclusion and implication for practice

The findings provide evidence of the positive effects of horticultural therapy on perceived well‐being among frail nursing home residents and expand the existing state of knowledge on the use of horticultural therapy in long‐term residential care. Among others nursing implications, they are also important to develop appropriate and meaningful nursing practice to improve frail residents' perceived quality of life in the institution they now call “home.”
Team composition and staff roles in a hybrid operating room: A prospective study using video observations
Authors: Bazzi May , Bergbom Ingegerd , Hellström Mikael , Fridh Isabell , Ahlberg Karin , Lundgren Solveig M.
Published: July 2019

Aim

The aim of the study was to evaluate team composition and staff roles in a hybrid operating room during endovascular aortic repairs.

Design

Quantitative descriptive design.

Methods

Nine endovascular aortic repairs procedures were video‐recorded between December 2014 and September 2015. The data analysis involved examining the work process, number of people in the room and categories of staff and their involvement in the procedure.

Results

The procedures were divided into four phases. The hybrid operating room was most crowded in phase 3 when the skin wound was open. Some staff categories were in the room for the entire procedure even if they were not actively involved. The largest number of people simultaneously in the room was 14.
An exploratory case study focusing on the creation, and development of a new political brand: The case of Aam Aadmi Party
Authors: Das Gupta Krishna
Published: July 2019

In the backdrop of India's rising prominence in BRICS (Brazil, Russia, India, China, and South Africa), understanding of its political environment, electoral competition, and constituent parties with their political ideologies contesting to form government attracts immense interest from the researchers in political science, political marketing, and public policy. Although literatures in political marketing are more than two decades mostly carried out in developed democratic systems like the United States, United Kingdom, Australia, and New Zealand, India as a posttransition democracy received relatively less attention. The article has been conceptualized in the context of 2014 Indian general elections Lok Sabha 2014 as an attempt to study application of political marketing principles in a cross‐cultural democracy. The author has probed the emergence of new political party Aam Aadmi Party riding on the success of Janlokpal (civil society movement), the marketing approach used by Aam Aadmi Party, essentially positioning and branding strategies, during the national elections and party institutionalization. Research strategy followed secondary research of published data for examining the new party creation from a marketing perspective.
Policy‐induced selection bias in pharmacoepidemiology: The example of coverage for Alzheimer's medications in British Columbia
Authors: Fisher Anat , Carney Greg , Bassett Ken , Maclure K. Malcolm , Dormuth Colin R.
Published: July 2019

Purposes

To assess the impact of a government‐sponsored reimbursement policy for cholinesterase inhibitors (ChEIs) on trends in physician visits with a diagnosis of Alzheimer's disease (AD).

Methods

Longitudinal population‐based study using interrupted time series methods. British Columbia outpatient claims data for individuals aged 65 and older were used to compute monthly AD visit rates and examine the impact of the ChEI reimbursement policy on the coding of AD. We examined trends in the number of patients with AD visits, the number of AD visits per patient, and visits with “competing” diagnoses (mental, neurological, and cerebrovascular disorders and accidental falls). Finally, we described demographic and clinical features of diagnosed patients.

Results

We analyzed 1.9 million AD visits. Faster growth in recorded AD visits was observed after the policy was implemented, from monthly growth of 7.5 visits per 100 000 person‐months before the policy (95% confidence interval [CI], 6.1‐8.9) to monthly growth of 16.5 per 100 000 person‐months after the policy (95% CI, 14.8‐18.3). After the implementation of the policy, we observed increased growth in the number of patients with recorded AD visits and the number of AD visits per patient, as well as a shift in diagnoses away from mental diseases and accidental falls to AD (diagnosis substitution).

Conclusions

British Columbia's reimbursement policy for ChEIs was associated with a significant acceleration in Alzheimer's visits. Evaluations of health services utilization and clinical outcomes following drug policy changes need to consider policy‐induced influences on the reliability of the data used in the analysis.
The synthesis of fulvic acid–thiourea amide derivates grafted polystyrene and its effect on the crystallization and performance of poly(lactic acid)
Authors: Duan Kun , Zhen Weijun
Published: July 2019

Fulvic acid–thiourea amide derivates (FA‐T) was synthesized via amidation with FA and thiourea, and its optimum reaction conditions were 7 h of reaction time, 1 wt% of sodium methylate, 130°C of reaction temperature, and 2 g of thiourea. Then, FA‐T grafted polystyrene (FA‐T‐PS) was synthesized by activators generated by electron transfer for atom transfer radical polymerization. Fourier transform infrared spectroscopy, static contact angle analysis, and X‐ray photoelectron spectroscopy confirmed that the synthesis of FA‐T‐PS. Then, poly(lactic acid)/FA‐T‐PS(PLA/FA‐T‐PS) composites were prepared by the melt blending with FA‐T‐PS as fillers. Mechanical test demonstrated that FA‐T‐PS increased the flexibility and ductility of PLA composites. Dynamic mechanical analysis revealed that FA‐T‐PS reduced friction and loss between PLA chain and filler, and further reformed had higher interfacial compatibility with PLA. Differential scanning calorimetric results and polarized optical microscopy analysis displayed that FA‐T‐PS had strong heterogeneous nucleation effect, which effectively enhanced the crystallization rate and the crystallinity of PLA. Friedman thermal decomposition kinetics presented that E
a of PLA/FA‐T‐PS (0.3 wt%) was increased by 52.94% compared with PLA, which demonstrated that FA‐T‐PS significantly enhanced the thermal stability of PLA. Therefore, FA‐T‐PS effectively improved the comprehensive performance of PLA. POLYM. ENG. SCI., 59:1787–1798, 2019. © 2019 Society of Plastics Engineers
Study on the Initiation Mechanism of Non‐Premixed Shock Induced Combustion in Supersonic Propellant Gas Jet
Authors: Qin Qiongyao , Zhang Xiaobing
Published: July 2019

The reflection of a supersonic propellant gas jet always happens during the firing of the weapon system of aircraft. The reflection induces complex non‐premixed shock induced combustion. It is of great importance to investigate the initiation mechanism of the combustion in the supersonic jet of propellant gas. The mechanism is vital for the design of any suppression method of the secondary combustion. To investigate the combustion in the reflected supersonic jet, a solid propellant combustion model and a numerical model based on compressible multispecies Navier‐Stokes equations are established. A detailed reaction mechanism consisting of 9 species and 12 reactions is utilized for the combustion of the propellant gas. Based on the models, the supersonic precursor flow field and the supersonic propellant gas jet flow are obtained and discussed. A secondary jet is observed which has not been reported before. A sandwich structure is proposed to reveal the initiation of the combustion. The oxygen supply in the secondary jet is found to be dominated by a vortex. An inert gas atmosphere can be adopted to suppress the mass transfer at the contact surface. Special devices could be designed to suppress the formation of the vortex in the secondary propellant jet.
MicroRNA‐139 is a predictor of prostate cancer recurrence and inhibits growth and migration of prostate cancer cells through cell cycle arrest and targeting IGF1R and AXL
Authors: Nam Robert K. , Benatar Tania , Wallis Christopher J. D. , Kobylecky Elizabeth , Amemiya Yutaka , Sherman Christopher , Seth Arun
Published: July 2019

Background: We previously identified a panel of five microRNAs (miRNAs) associated with biochemical recurrence and metastasis following prostatectomy from prostate cancer patients using next‐generation sequencing‐based whole miRNome sequencing and quantitative polymerase chain reaction‐based validation analysis. In this study, we examined the mechanism of action of miR‐139‐5p, one of the downregulated miRNAs identified in the panel.

Methods: Using a cohort of 585 patients treated with radical prostatectomy, we examined the prognostic significance of miR‐139 (dichotomized around the median) using the Kaplan‐Meier method and Cox proportional hazard models. We validated these results using The Cancer Genome Atlas (TCGA) data. We created cell lines that overexpressed miR‐139 to confirm its targets as well as examine pathways through which miR‐139 may function using cell‐based assays.

Results: Low miR‐139 expression was significantly associated with a variety of prognostic factors in prostate cancer, including Gleason score, pathologic stage, margin positivity, and lymph node status. MiR‐139 expression was associated with prognosis: the cumulative incidence of biochemical recurrence and metastasis were significantly lower among patients with high miR‐139 expression (P = .0004 and .038, respectively). Validation in the TCGA data set showed a significant association between dichotomized miR‐139 expression and biochemical recurrence (odds ratio, 0.52; 95% confidence interval, 0.33‐0.82). Overexpression of miR‐139 in prostate cancer cells led to a significant reduction in cell proliferation and migration compared with control cells, with cells arrested in G2 of cell cycle. IGF1R and AXL were identified as potential targets of miR‐139 based on multiple miRNA‐binding sites in 3′‐untranslated regions of both the genes and their association with prostate cancer growth pathways. Luciferase assays verified AXL and IGF1R as direct targets of miR‐139. Furthermore, immunoblotting of prostate cancer cells demonstrated IGF1R and AXL protein expression were inhibited by miR‐139 treatment, which was reversed by the addition of miR‐139 antagomir. Examination of the molecular mechanism of growth inhibition by miR‐139 revealed the downregulation of activated AKT and cyclin D1, with upregulation of the CDK inhibitor p21.

Conclusions: miR‐139 is associated with improved prognosis in patients with localized prostate cancer, which may be mediated through downregulation of IGF1R and/or AXL and associated signaling pathway components.
The pathological upgrading after radical prostatectomy in low‐risk prostate cancer patients who are eligible for active surveillance: How safe is it to depend on bioptic pathology?
Authors: Verep Samed , Erdem Selcuk , Ozluk Yasemin , Kilicaslan Isin , Sanli Oner , Ozcan Faruk
Published: July 2019

Background

Active surveillance (AS) is one of the treatment alternatives in low‐risk prostate cancer (PCa). The pathological upgrading after radical prostatectomy (RP) were investigated in patients who were eligible for AS in the present study.

Methods

Between August 2006 and July 2017, 627 patients underwent RP in our institution. One hundred and thirty‐six patients who were eligible for AS at the time of RP were included in this study. The previously defined AS criteria Gleason 3 + 3=6 adenocarcinoma at maximum two biopsy cores, prostate‐specific antigen (PSA) < 10 ng/mL and clinical T stage ≤ 2a were used in the study. The demographics, clinical, and histopathological outcomes were retrospectively compared between two groups, which were divided in accordance with the upgrading status at final pathology as Group 1 (n = 67, upgrading) and Group 2 (n = 69, nonupgrading).

Results

Gleason upgrading (GU) was found in 67 (49.3%) patients, and 17 patients (12.5%) were upstaged to pT3a. The upgrading to Gleason 3 + 4 was reported in 38.7% of patients, however, 7.4%, and 3.7% of the patients were upgraded to Gleason 4 + 3, and Gleason 4 + 4, respectively. The 10.3% of the patients had extraprostatic involvement, and the rate (19.4% vs 1.4%, P = .002) was significantly higher in Group 1. PSA density (P = .001), tumor size (P < .001), tumor percentage (P < .001), apical involvement (P = .013), and perineural invasion (P < .001) in RP specimen were higher in Group 1. Multivariate analysis showed that perineural invasion (OR = 4.26; 95%CI: 1.76‐10.33; P = .001) and pathologic T stage (OR = 5.45; 95%CI: 1.08‐27.4; P = .04) were independently associated with GU.

Conclusions

Since 12.5% of the patients upstaged to pT3a disease, and there is a possible risk of Gleason 4 pattern, upgrading of the tumor should carefully be kept in mind before offering AS to low‐risk patients with PCa.
Production of pyrrolizidine alkaloids and shikonins in Echium plantagineum L. in response to various plant stressors
Authors: Skoneczny Dominik , Zhu Xiaocheng , Weston Paul A , Gurr Geoff M , Callaway Ragan M , Weston Leslie A
Published: July 2019

Background

Echium plantagineum, a native of Europe and Africa, is a noxious invasive weed in Australia forming monocultural stands in pastures and rangelands. It produces a complex mixture of bioactive secondary metabolites, including toxic pyrrolizidine alkaloids (PAs), that protect the plant from insect and livestock herbivory and naphthoquinones (NQs), which suppress competition from weeds, insects and pathogens, and also influence invasion success. However, the extent to which allelochemical production is impacted by environmental factors, thereby influencing plant defense against pests, remains unclear.

Results

Following plant stress induced by drought, herbivory and high temperature, extracts of E. plantagineum shoots and roots were subjected to metabolic profiling by UPLC‐MS‐DAD‐ QToF mass spectrometry. Abundance of NQs, especially deoxyshikonin, shikonin and dimethylacrylshikonin, rapidly increased in roots exposed to elevated temperatures. Water withholding initially increased NQ abundance, but prolonged drought resulted in reduced total PAs and NQs. Intraspecific competition elevated the production of NQs, whereas simulated herbivory had no initial effect on NQs. Following herbivory, the abundance of the PA 3′‐O‐acetylechimidine‐N‐oxide in seedling shoots was increased.

Conclusions

Differential accumulation of defense metabolites by E. plantagineum following exposure to various stressors suggested stress‐dependent biosynthetic regulation, particularly with respect to NQ production, which was rapidly induced following drought, intraspecific competition and high temperature treatment, thereby positively impacting resistance or defense against herbivores, weeds and pathogens. We propose that trade‐offs between above‐ and below‐ground metabolism in E. plantagineum may facilitate allelochemical production in response to stress, rendering plants with an enhanced ability to defend against other neighboring plants, insects and microbes, with allelochemical production further facilitated by catabolic recycling following lengthier exposure to stress. © 2019 Society of Chemical Industry
Sonochemical Modification of SiGe Layers for Photovoltaic Applications
Authors: Nadtochiy Andriy , Korotchenkov Oleg , Schlosser Viktor
Published: July 2019

To improve the photovoltaic response of SiGe and amorphous silicon (a‐Si)/SiGe surfaces, a sonochemical treatment in chloroform (CHCl3) is used. The use of the sonochemical reaction slows down the observed surface photovoltage (SPV) decay and enhances its magnitude in SiGe and a‐Si/SiGe thin layers grown on Si. The average surface‐integrated photovoltage and decay time can increase up to 50%. This effect is not observed in distilled water, indicative of the fact that CH‐containing radicals can lead to the observed improvements. It is suggested that the effect can be explained as follows: CHCl3 is decomposed and produces hydrocarbon chains, which are then decomposed further away into hydrogen and carbon. The reactive Si dangling bonds revealed on the surface of SiGe alloys are saturated by the hydrocarbon species to passivate the surface. It is, therefore, advantageous to use sonochemical surface modification of silicon–germanium‐based photovoltaic materials in chloroform solutions.
Spin Pumping in Asymmetric Fe50Pt50/Cu/Fe20Ni80 Trilayer Structure
Authors: Medwal Rohit , Gupta Surbhi , Rawat Rajdeep S. , Subramanian Annapoorni , Fukuma Yasuhiro
Published: July 2019

Herein, spin transport dynamics across asymmetric Fe50Pt50/Cu/Fe20Ni80 soft‐magnetic trilayer structure is reported and thereby modulation of magnetic parameters including damping and effective field is determined by means of the angular dependence of broadband ferromagnetic resonance measurements. At distinct precession of individual magnetic layer, spin‐pumping is found to be prevalent with expected linewidth increase. Mutual precession for wide range of resonance configuration reveals a collective reduction in anisotropy field of around 200 mT for both Fe50Pt50 and Fe20Ni80 systems. Subsequent observation of no‐excess interface damping shows the possible control of spin‐pumping effect by tuning the net flow of spin‐current in a multilayer structure. These experimental findings have significance for microwave devices that require tunable anisotropy field in magnetic multilayers.
Empirical evaluation of the implementation of the EMA guideline on missing data in confirmatory clinical trials: Specification of mixed models for longitudinal data in study protocols
Authors: Häckl Sebastian , Koch Armin , Lasch Florian
Published: July 2019

In confirmatory clinical trials, the prespecification of the primary analysis model is a universally accepted scientific principle to allow strict control of the type I error. Consequently, both the ICH E9 guideline and the European Medicines Agency (EMA) guideline on missing data in confirmatory clinical trials require that the primary analysis model is defined unambiguously. This requirement applies to mixed models for longitudinal data handling missing data implicitly. To evaluate the compliance with the EMA guideline, we evaluated the model specifications in those clinical study protocols from development phases II and III submitted between 2015 and 2018 to the Ethics Committee at Hannover Medical School under the German Medicinal Products Act, which planned to use a mixed model for longitudinal data in the confirmatory testing strategy. Overall, 39 trials from different types of sponsors and a wide range of therapeutic areas were evaluated. While nearly all protocols specify the fixed and random effects of the analysis model (95%), only 77% give the structure of the covariance matrix used for modeling the repeated measurements. Moreover, the testing method (36%), the estimation method (28%), the computation method (3%), and the fallback strategy (18%) are given by less than half the study protocols. Subgroup analyses indicate that these findings are universal and not specific to clinical trial phases or size of company. Altogether, our results show that guideline compliance is to various degrees poor and consequently, strict type I error rate control at the intended level is not guaranteed.
Geographic authentication of the traditional Chinese medicine Atractylodes macrocephala Koidz. (Baizhu) using stable isotope and multielement analyses
Authors: Hu Ling , Chen Xianfeng , Yang Jian , Guo Lanping
Published: July 2019

Rationale

Atractylodes macrocephala Koidz (Baizhu) is a valuable traditional Chinese medicine, and medicines of that type originating from Zhejiang province are the most famous and much more expensive than those from other regions. Driven by the great difference in prices, fraudulent labeling often occurs. In order to protect the interests of consumers, producers and honest traders, reliable techniques for the geographic authentication of Baizhu are needed urgently.

Methods

The stable isotope ratios of five light elements (C, N, H, O and S) in Baizhu samples originating from four provinces of China were determined with an elemental analyzer coupled to isotope ratio mass spectrometry, and the concentrations of 45 elements in these samples were measured using inductively coupled plasma mass spectrometry. Chemometric approaches including principal component analysis (PCA) and orthodox partial least squares discriminant analysis (OPLS‐DA) were applied to the obtained data.

Results

The PCA results showed that the techniques enabled clear classification of the Baizhu samples into three clusters: A (Zhejiang province), B (Shaanxi province) and C (Hebei and Ahui provinces). Furthermore, OPLS‐DA using 27 key variables provided 100% correct discrimination between samples originating from Zhejiang province and those from the other three provinces.

Conclusions

Stable isotope ratio and multielement analyses in combination with chemometric approaches showed great potential for the geographic authentication of Baizhu, providing a promising method for the control of fraudulent labeling that frequently occurs with traditional herbal medicines in China.
Neurosurgery medical robot Remebot for the treatment of 17 patients with hypertensive intracerebral hemorrhage
Authors: Wang Tao , Zhao Quan‐Jun , Gu Jian‐Wen , Shi Tie‐Jun , Yuan Xujun , Wang Jia , Cui Shao‐Jie
Published: July 2019

Objective

To verify the minimally invasive surgical approach and therapeutic effects of using the medical neurosurgery robot Remebot to treat hypertensive intracerebral hemorrhage (HICH).

Methods

Clinical data for 17 HICH patients were analyzed retrospectively. Hematoma evacuation and tube drainage using Remebot frameless stereotaxic techniques were performed for all patients, and urokinase was injected into the hematomas after the operations.

Results

Robot‐assisted stereotactic techniques can accurately guide hematoma punctures, and no deaths occurred among these patients. The average positioning error was 1.28 ± 0.49 mm. The average drainage duration was 3.4 days. The 3‐month postoperative follow‐up revealed improved neurological functions and quality of life for all patients.

Conclusions

The medical neurosurgery robot Remebot is minimally invasive, has high positional accuracy, and facilitates surgical planning according to the shape of the hematoma. Therefore, robot‐assisted surgery using Remebot represents a safe and effective treatment method for hematoma evacuation and tube drainage in HICH patients.
H∞ boundary control for a class of nonlinear stochastic parabolic distributed parameter systems
Authors: Zhang Xiu‐Mei , Wu Huai‐Ning
Published: July 2019

This paper addresses the problem of H∞ boundary control for a class of nonlinear stochastic distributed parameter systems expressed by parabolic stochastic partial differential equations (SPDEs) of Itô type. A simple but effective H∞ boundary static output feedback (SOF) control scheme with collocated boundary measurement is introduced to ensure the local exponential stability in the mean square sense with an H∞ performance. By using the semigroup theory, the disturbance‐free closed‐loop well‐posedness analysis is first given. Then, based on the SPDE model, a general linear matrix inequality based H∞ boundary SOF control design is provided via Lyapunov technique and infinite‐dimensional infinitesimal operator, such that the disturbance‐free closed‐loop system is locally exponentially stable in the mean square sense and the H∞ performance of disturbance attenuation can also be achieved in the presence of disturbances. Finally, simulation results on a stochastic Fisher‐Kolmogorov‐Petrovsky‐Piscounov equation illustrate the effectiveness of the proposed method.
Control of Catalytic Activity of Nano‐Au through Tailoring the Fermi Level of Support
Authors: Liu Yinglei , Chen Hao , Xu Changjin , Sun Yuming , Li Song , Jiang Min , Qin Gaowu
Published: July 2019

The catalytic properties of nanometals are strongly dependent on their electronic states which, are influenced by the interaction with the supports. However, a precise manipulation of the electronic interaction is lacking, and the nature of the interaction is still ambiguous. Herein, using Au/ZnFexCo2−xO4 (x = 0–2) as a model system with continuously tuned Fermi levels of supports, the electronic structure of the Au catalyst can be precisely controlled by changing the Fermi level of the support, which arises from the charge redistribution between the two phases. A higher Fermi level of ZnFe2O4 support makes nano‐Au negatively charged and thus facilitates the oxidation of CO, and in contrast, a lower Fermi level of ZnCo2O4 support makes nano‐Au positively charged and is preferential to the oxidation of benzyl alcohol. This work represents a solid step towards exploration of advanced catalysts with deliberate design of electronic structure and catalytic properties.
Guiding the Morphology of Amyloid Assemblies by Electrostatic Capping: from Polymorphic Twisted Fibrils to Uniform Nanorods
Authors: Zottig Ximena , Al‐Halifa Soultan , Babych Margaryta , Quittot Noé , Archambault Denis , Bourgault Steve
Published: July 2019

Peptides that self‐assemble into cross‐β‐sheet amyloid structures constitute promising building blocks to construct highly ordered proteinaceous materials and nanoparticles. Nevertheless, the intrinsic polymorphism of amyloids and the difficulty of controlling self‐assembly currently limit their usage. In this study, the effect of electrostatic interactions on the supramolecular organization of peptide assemblies is investigated to gain insights into the structural basis of the morphological diversities of amyloids. Different charged capping units are introduced at the N‐terminus of a potent β‐sheet‐forming sequence derived from the 20–29 segment of islet amyloid polypeptide, known to self‐assemble into polymorphic fibrils. By tuning the charge and the electrostatic strength, different mesoscopic morphologies are obtained, including nanorods, rope‐like fibrils, and twisted ribbons. Particularly, the addition of positive capping units leads to the formation of uniform rod‐like assemblies, with lengths that can be modulated by the charge number. It is proposed that electrostatic repulsions between N‐terminal positive charges hinder β‐sheet tape twisting, leading to a unique control over the size of these cytocompatible nanorods by protofilament growth frustration. This study reveals the high susceptibility of amyloid formation to subtle chemical modifications and opens to promising strategies to control the final architecture of proteinaceous assemblies from the peptide sequence.
Is My Phone Listening in? On the Feasibility and Detectability of Mobile Eavesdropping
Authors: Kröger Jacob Leon , Raschke Philip
Published: July 2019

Besides various other privacy concerns with mobile devices, many people suspect their smartphones to be secretly eavesdropping on them. In particular, a large number of reports has emerged in recent years claiming that private conversations conducted in the presence of smartphones seemingly resulted in targeted online advertisements. These rumors have not only attracted media attention, but also the attention of regulatory authorities. With regard to explaining the phenomenon, opinions are divided both in public debate and in research. While one side dismisses the eavesdropping suspicions as unrealistic or even paranoid, many others are fully convinced of the allegations or at least consider them plausible. To help structure the ongoing controversy and dispel misconceptions that may have arisen, this paper provides a holistic overview of the issue, reviewing and analyzing existing arguments and explanatory approaches from both sides. Based on previous research and our own analysis, we challenge the widespread assumption that the spying fears have already been disproved. While confirming a lack of empirical evidence, we cannot rule out the possibility of sophisticated large-scale eavesdropping attacks being successful and remaining undetected. Taking into account existing access control mechanisms, detection methods, and other technical aspects, we point out remaining vulnerabilities and research gaps.
Probing out-of-time-order correlators
Authors: Chaudhuri Soumyadeep , Loganayagam R.
Published: July 2019

Abstract

We present a method to probe the Out-of-Time-Order Correlators (OTOCs) of a general system by coupling it to a harmonic oscillator probe. When the system’s degrees of freedom are traced out, the OTOCs imprint themselves on the generalized influence functional of the oscillator. This generalized influence functional leads to a local effective action for the probe whose couplings encode OTOCs of the system. We study the structural features of this effective action and the constraints on the couplings from microscopic unitarity. We comment on how the OTOCs of the system appear in the OTOCs of the probe.
A Cohort Perspective on the Demography of Grandparenthood: Past, Present, and Future Changes in Race and Sex Disparities in the United States
Authors: Margolis Rachel , Verdery Ashton M.
Published: July 2019

How has the demography of grandparenthood changed over the last century? How have racial inequalities in grandparenthood changed, and how are they expected to change in the future? Massive improvements in mortality, increasing childlessness, and fertility postponement have profoundly altered the likelihood that people become grandparents as well as the timing and length of grandparenthood for those that do. The demography of grandparenthood is important to understand for those taking a multigenerational perspective of stratification and racial inequality because these processes define the onset and duration of intergenerational relationships in ways that constrain the forms and levels of intergenerational transfers that can occur within them. In this article, we discuss four measures of the demography of grandparenthood and use simulated data to estimate the broad contours of historical changes in the demography of grandparenthood in the United States for the 1880–1960 birth cohorts. Then we examine race and sex differences in grandparenthood in the past and present, which reveal declining inequality in the demography of grandparenthood and a projection of increasing group convergence in the coming decades.
ANALYZING MORTALITY BOND INDEXES VIA HIERARCHICAL FORECAST RECONCILIATION
Authors: Li Han , Tang Qihe
Published: July 2019

In recent decades, there has been significant growth in the capital market for mortality- and longevity-linked bonds. Therefore, modeling and forecasting the mortality indexes underlying these bonds have crucial implications for risk management in life insurance companies. In this paper, we propose a hierarchical reconciliation approach to constructing probabilistic forecasts for mortality bond indexes. We apply this approach to analyzing the Swiss Re Kortis bond, which is the first “longevity trend bond” introduced in the market. We express the longevity divergence index associated with the bond’s principal reduction factor (PRF) in a hierarchical setting. We first adopt time-series models to obtain forecasts on each hierarchical level, and then apply a minimum trace reconciliation approach to ensure coherence of forecasts across all levels. Based on the reconciled probabilistic forecasts of the longevity divergence index, we estimate the probability distribution of the PRF of the Kortis bond, and compare our results with those stated in Standard and Poor’s report on pre-sale information. We also illustrate the strong performance of the approach by comparing the reconciled forecasts with unreconciled forecasts as well as those from the bottom-up approach and the optimal combination approach. Finally, we provide first insights on the interest spread of the Kortis bond throughout its risk period 2010–2016.
Employer preferences and political alignments during the Eurocrisis: Evidence from the Portuguese case
Authors: Lisi Marco , Loureiro João
Published: July 2019

This paper strives to shed light on the interaction between business groups and the main governing parties after the onset of the economic crisis through a “thick narrative” approach. By focusing on the Portuguese case, the study aims to examine the preferences of the employer confederations during the distinct phases of the economic crisis and to analyze the political alignments established with different party governments. This contribution confirms the fragmentation of business interests on the one hand and tensions between the right-wing government and the main employer confederations on the other. While a pragmatic approach to party politics seems to be the predominant trend, historical and institutional legacies are still important factors when considering the actions and inner tensions of these organizations.
Solving the inertial particle equation with memory
Authors: Haller George
Published: July 2019

The dynamics of spherical particles in a fluid flow is governed by the well-accepted Maxey–Riley equation. This equation of motion simply represents Newton’s second law, equating the rate of change of the linear momentum with all forces acting on the particle. One of these forces, the Basset–Boussinesq memory term, however, is notoriously difficult to handle, which prompts most studies to ignore this term despite ample numerical and experimental evidence of its significance. This practice may well change now due to a clever reformulation of the particle equation of motion by Prasath, Vasan & Govindarajan (J. Fluid Mech., vol. 868, 2019, pp. 428–460), who convert the Maxey–Riley equation into a one-dimensional heat equation with non-trivial boundary conditions. Remarkably, this reformulation confirms earlier estimates on particle asymptotics, yields previously unknown analytic solutions and leads to an efficient numerical scheme for more complex flow fields.
Weak shock reflection in channel flows for dense gases
Authors: Kluwick A. , Cox E. A.
Published: July 2019

The canonical problem of transonic dense gas flows past two-dimensional compression/expansion ramps has recently been investigated by Kluwick & Cox (J. Fluid Mech., vol. 848, 2018, pp. 756–787). Their results are for unconfined flows and have to be supplemented with solutions of another canonical problem dealing with the reflection of disturbances from an opposing wall to finally provide a realistic picture of flows in confined geometries of practical importance. Shock reflection in dense gases for transonic flows is the problem addressed in this paper. Analytical results are presented in terms of similarity parameters associated with the fundamental derivative of gas dynamics$(\unicode[STIX]{x1D6E4})$, its derivative with respect to the density at constant entropy$(\unicode[STIX]{x1D6EC})$and the Mach number$(M)$of the upstream flow. The richer complexity of flows scenarios possible beyond classical shock reflection is demonstrated. For example: incident shocks close to normal incidence on a reflecting boundary can lead to a compound shock–wave fan reflected flow or a pure wave fan flow as well as classical flow where a compressive reflected shock attached to the reflecting boundary is observed. With incident shock angles sufficiently away from normal incidence regular reflection becomes impossible and so-called irregular reflection occurs involving a detached reflection point where an incident shock, reflected shock and a Mach stem shock which remains connected to the boundary all intersect. This triple point intersection which also includes a wave fan is known as Guderley reflection. This classical result is demonstrated to carry over to the case of dense gases. It is then finally shown that the Mach stem formed may disintegrate into a compound shock–wave fan structure generating an additional secondary upstream shock. The aim of the present study is to provide insight into flows realised, for example, in wind tunnel experiments where evidence for non-classical gas dynamic effects such as rarefaction shocks is looked for. These have been predicted theoretically by the seminal work of Thompson (Phys. Fluids, vol. 14 (9), 1971, pp. 1843–1849) but have withstood experimental detection in shock tubes so far, due to, among others, difficulties to establish purely one-dimensional flows.
The authentic classroom
Authors: Lowe Kevin B.
Published: July 2019

A panel of eight leadership scholars was convened to participate in a panel at the 20th International Leadership Association Conference to discuss the benefits and the pitfalls of applying authentic leadership theory to the classroom setting. Inspired by Ken Parry's masterful teaching and the authenticity that he displayed in the classroom, this paper provides an overview of the panel's discussion as they grappled with the attractions, the challenges and the risks that are posed to both teacher-scholars and student-scholars in bringing their full selves into the classroom.
Adopting Bricolage to Overcome Resource Constraints: The Case of Social Enterprises in Rural India
Authors: Hota Pradeep Kumar , Mitra Sumit , Qureshi Israr
Published: July 2019

Social enterprises (SEs) primarily aim to create social value, that is, to generate benefits or reduce costs for society, while maintaining financial sustainability. Owing to their unique operating conditions and organizational characteristics, SEs face more severe resource challenges than their commercial counterparts. These challenges are exacerbated for SEs operating in emerging economies with complex social contexts. Overcoming these resource constraints and social challenges is vital for SEs to achieve their mission. Using an inductive multiple case-study approach, we identify a unique bricolage solution for achieving the dual objectives of SEs. Our findings suggest that identifying locally embeddedvillage level entrepreneursis a bricolage activity that social entrepreneurs leverage in the resource constrained environment of emerging economies, especially for the social enterprises that are active in the villages but were founded by social entrepreneurs who are not from these villages. This article therefore contributes to both social entrepreneurship literature as well as entrepreneurial bricolage literature and has important implications for future research and practice.
Institutional Bridging for SME High-Distance Internationalisation to
China: A Contextualised Explanation
Authors: Couper Carole
Published: July 2019

This article offers a contextualised explanation of the process of institutional
bridging by Delta, a British SME, in order to internationalise to China across
high institutional distance. The study uncovers three novel mechanisms of
‘Cross-institutional Dissonance Mitigation’,
‘Multi-level Strategic Embedding’, and
‘Cross-institutional Consonance Retuning’ to explain how
and why a failing SME with limited resources and networks was able to bridge the
institutional distance and internationalise to the challenging Chinese market.
This article contributes to the literature on SME internationalisation across
high institutional distance by opening the ‘black box’ of
SME institutional bridging, hence demonstrating the benefits of contextualised
explanations to extend research into internationalisation phenomena that span
multiple institutional boundaries.
Comparative Research is Harder Than We Thought: Regional Differences in Experts’ Understanding of Electoral Integrity Questions
Authors: Castanho Silva Bruno , Littvay Levente
Published: July 2019

Expert evaluations about countries form the backbone of comparative political research. It is reasonable to assume that such respondents, no matter the region they specialize in, will have a comparable understanding of the phenomena tapped by expert surveys. This is necessary to get results that can be compared across countries, which is the fundamental goal of these measurement activities. We empirically test this assumption using measurement invariance techniques which have not been applied to expert surveys before. Used most often to test the cross-cultural validity and translation effects of public opinion scales, the measurement invariance tests evaluate the comparability of scale items across any groups. We apply them to the Perceptions of Electoral Integrity (PEI) dataset. Our findings suggest that cross-regional comparability fails for all eleven dimensions identified in PEI. Results indicate which items remain comparable, at least across most regions, and point to the need of more rigorous procedures to develop expert survey questions.
Under Construction: Alternative Spaces of Discourse at the National Library of Israel (Critical Essay)
Authors: Kargon Jeremy
Published: July 2019

A new building for the National Library of Israel (NLI), scheduled for completion in 2021, is the culmination of a two-decade process of institutional transformation. Formerly known as the Jewish National and University Library, the NLI has historically served simultaneously as Israel's official state repository, as the Hebrew University's central library, and as a “library of the Jewish people.” Like other national libraries around the world, including elsewhere in the Middle East, the National Library of Israel has had to grapple with accelerated changes in management of library collections due to the proliferation of digital media. More fundamental, however, have been changes in the cultural expectations about how libraries should function. Since 1998, the NLI has sought to expand its mission to promote not only scholarship but also cultural “discourse” among Israel's diverse constituencies. The architectural design of NLI's new edifice was intended, therefore, to do more than house the functional requirements of a modern library. It was commissioned to express through its design the significance of the transformed institution for the Israeli public. Towards that goal, a highly publicized competition for the NLI's design was held in 2012. The original two-stage competition ended in controversy after the architect endorsed by the jurors was dismissed. Yet a review of designs submitted by four Israeli architects in that first competition shows how public spaces, affiliated with public institutions, are expected to foster public discourse in Israel. Whether that discourse is cultural or political, contentious or contradictory, these alternative designs for the NLI illustrate common themes based upon specific environmental tropes, familiar across a broad spectrum of Israeli society.
Effect of process-induced common bean hardness on structural properties of in vivo generated boluses and consequences for in vitro starch digestion kinetics
Authors: Pallares Pallares Andrea , Loosveldt Bram , Karimi Solomon N. , Hendrickx Marc , Grauwet Tara
Published: July 2019

In the present study, we evaluated the effect of process-induced common bean hardness on structural properties ofin vivogenerated boluses and the consequences forin vitrostarch digestion. Initially, the impact of human mastication on the particle size distribution (PSD) of oral boluses from common beans with different process-induced hardness levels was investigated through a mastication study. Then the effect of structural properties of selected boluses onin vitrostarch digestion kinetics was assessed. For a particular process-induced hardness level, oral boluses had similar PSD despite differences in masticatory parameters between participants of the mastication study. At different hardness levels, a clear effect of processing (P<0·0001) was observed. However, the effect of mastication behaviour (P=0·1141) was not significant. Two distinctive fractions were present in all boluses. The first one was a cotyledon-rich fraction consisting of majorly small particles (40–125 µm), which could be described as individual cells based on microscopic observations. This fraction increased with a decrease in process-induced hardness. The second fraction (>2000 µm) mostly contained seed coat material and did not change based on hardness levels. Thein vitrostarch digestion kinetics of common bean boluses was only affected by process-induced hardness. After kinetic modelling, significant differences were observed between the reaction rate constant of boluses generated from the hardest beans and those obtained from softer ones. Overall this work demonstrated that thein vitronutritional functionality of common beans is affected to a greater extent by structural properties induced by processing than by mechanical degradation in the mouth.