bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanocrystalline cellulose/fluorinated polyacrylate latex via RAFT‐mediated surfactant‐free emulsion polymerization and its application as waterborne textile finishing agent
Authors: Yao Hongtao , Zhou Jianhua , Li Hong , Zhao Jiaojiao
Published: April 2019

A simple method for nanocrystalline cellulose (NCC)/fluorinated polyacrylate was developed by RAFT‐mediated surfactant‐free emulsion polymerization, in which the nanocomposites formed a core‐shell spherical morphology. The influence of the content of NCC‐g‐(PAA‐b‐PHFBA) (AA was acrylic acid, HFBA was hexafluorobutyl acrylate) on the properties of latex and film were systematically studied. The monomer conversion, the tensile strength, and water–oil repellency of film increased first and then decreased, the latex particle size decreased first and then decreased, when the content of NCC‐g‐(PAA‐b‐PHFBA) increased from 1 to 6 wt %. Elongation at break and thermal stability distinctly decreased when the content of NCC‐g‐(PAA‐b‐PHFBA) gradually increased. XPS showed that the fluorine‐containing groups well concentrated at the film–air interfaces during the annealing process. SEM analysis revealed that the treated fiber had a rugged surface, and the treated fabric had an excellent water repellency. In addition, this green grafting method in water offered a new perspective for the fabrication of exceptional NCC‐based nanocomposites with NCC as the core and also helped to promote the potential applicability of NCC in a range of multipurpose applications. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1305–1314
Synthesis of Atom‐Precise Chiral Ag14 Clusters Protected by Penicillamine Ligands
Authors: Li Bing , Kong Yu‐Jin , Li Si , Liu Xiao‐Fei , Luo Peng , Zang Shuang‐Quan
Published: April 2019

A pair of atom‐precise chiral silver(I) nanocluster enantiomers (Ag14‐d and Ag14‐l) protected by d‐ and l‐penicillamine ligands is reported. Crystallographic structures reveal that the nanoclusters consist of a S2− template and a chiral Ag14 core stabilized by 12 penicillamine ligands. The penicillamine ligands show two binding fashions: (i) only thiolate coordination, and (ii) thiolate and carboxylate co‐coordination. Meanwhile, the two enantiomers show strong circular dichroism with opposite signals (mirror image relationship) owing to the chiral metallic core induced by chiral ligands, suggesting that the nanoclusters have well‐defined stereostructures as common chiral molecules do. The proton conductivity is also explored due to the existence of both amino groups and carboxylate groups from the penicillamine ligands, which is beneficial to construct H‐bond network for proton transfer.
Modeling of a Waveguide‐Based UV–VIS–IR Spectrometer Based on a Lateral (In,Ga)N Alloy Gradient
Authors: Grundmann Marius
Published: April 2019

The author presents the simulation and modeling of a waveguide‐based ultracompact spectrometer for the near‐ultraviolet through visible to infrared spectral range based on a lateral material gradient of InxGa1−xN from GaN to InN. Using reasonable material parameters from the literature, the reconstruction of a model spectrum in the range 0.8–3.5 eV is simulated for a lateral gradient from x = 0 to x = 1. The experimental realization of such spectrometer could drastically simplify confocal scanning microscopy and make spectral analysis and hyperspectral imaging available in hand‐held and smartphone devices.
Ab‐Initio Investigation of the Band Alignment Between Cu2ZnSnS4 and Different Buffer Materials (Al2ZnO4, CeO2, ZnSnO3)
Authors: Albar Arwa , Schwingenschlögl Udo
Published: April 2019

Limited efficiency of Cu2ZnSnS4 (CZTS) solar cells due to high recombination rates at the CZTS–buffer interface calls for alternative buffer materials to enhance the open circuit voltage and, therefore, the device performance. By means of ab‐initio hybrid functional calculations, the authors investigate the interfaces between the p‐type absorber CZTS and the n‐type buffer materials Al2ZnO4, CeO2, or ZnSnO3 to evaluate the band alignment. Strong hole confinement is predicted for the CZTS/Al2ZnO4 and CZTS/ZnSnO3 interfaces. A small conduction band offset of 0.31 eV is obtained for the CZTS/ZnSnO3 interface, indicating that ZnSnO3 should be considered for improving the efficiency of CZTS solar cells.
Sequential Targeting TGF‐β Signaling and KRAS Mutation Increases Therapeutic Efficacy in Pancreatic Cancer
Authors: Pei Yuanyuan , Chen Liang , Huang Yukun , Wang Jiahao , Feng Jingxian , Xu Minjun , Chen Yu , Song Qingxiang , Jiang Gan , Gu Xiao , Zhang Qian , Gao Xiaoling , Chen Jun
Published: April 2019

Pancreatic cancer is a highly aggressive malignancy that strongly resists extant treatments. The failure of existing therapies is majorly attributed to the tough tumor microenvironment (TME) limiting drug access and the undruggable targets of tumor cells. The formation of suppressive TME is regulated by transforming growth factor beta (TGF‐β) signaling, while the poor response and short survival of almost 90% of pancreatic cancer patients results from the oncogenic KRAS mutation. Hence, simultaneously targeting both the TGF‐β and KRAS pathways might dismantle the obstacles of pancreatic cancer therapy. Here, a novel sequential‐targeting strategy is developed, in which antifibrotic fraxinellone‐loaded CGKRK‐modified nanoparticles (Frax‐NP‐CGKRK) are constructed to regulate TGF‐β signaling and siRNA‐loaded lipid‐coated calcium phosphate (LCP) biomimetic nanoparticles (siKras‐LCP‐ApoE3) are applied to interfere with the oncogenic KRAS. Frax‐NP‐CGKRK successfully targets the tumor sites through the recognition of overexpressed heparan sulfate proteoglycan, reverses the activated cancer‐associated fibroblasts (CAFs), attenuates the dense stroma barrier, and enhances tumor blood perfusion. Afterward, siKras‐LCP‐ApoE3 is efficiently internalized by the tumor cells through macropinocytosis and specifically silencing KRAS mutation. Compared with gemcitabine, this sequential‐targeting strategy significantly elongates the lifespans of pancreatic tumor‐bearing animals, hence providing a promising approach for pancreatic cancer therapy.
Nitrogen and Phosphorus Codoped Vertical Graphene/Carbon Cloth as a Binder‐Free Anode for Flexible Advanced Potassium Ion Full Batteries
Authors: Qiu Wenda , Xiao Hongbing , Li Yu , Lu Xihong , Tong Yexiang
Published: April 2019

With the fast development in flexible electronic technology, power supply devices with high performance, low‐cost, and flexibility are becoming more and more important. Potassium ion batteries (KIBs) have a brilliant prospect for applications benefiting from high voltage, lost cost, as well as similar electrochemistry to lithium ion batteries (LIBs). Although carbon materials have been studied as KIBs anodes, their rate capability and cycling stability are still unsatisfactory due to the large‐size potassium ions. Herein, a nitrogen (N) and phosphorus (P) dual‐doped vertical graphene (N, P‐VG) uniformly grown on carbon cloth (N, P‐VG@CC) is reported as a binder‐free anode for flexible KIBs. With the combined advantages of rich active sites, highly accessible surface, highly conductive network, larger interlayer spacing as well as robust structural stability, this binder‐free N, P‐VG@CC anode exhibits high capacity (344.3 mAh g−1), excellent rate capability (2000 mA g−1; 46.5% capacity retention), and prominent long‐term cycling stability (1000 cycles; 82% capacity retention), outperforming most of the recently reported carbonaceous anodes. Moreover, a potassium ion full cell is successfully assembled on the basis of potassium Prussian blue (KPB)//N, P‐VG@CC, exhibiting a large energy density of 232.5 Wh kg−1 and outstanding cycle stability.
Copper‐Alloyed Precipitation‐Hardenable‐Ferritic‐Pearlitic Steel for Energy‐Efficient and Distortion‐Reduced Production of Cold‐Formed, High‐Strength Structural Components
Authors: Meiler Stefan , Hoffmann Frank , Schwich Hannah , Kawalla Rudolf , Bleck Wolfgang , Prahl Ulrich
Published: April 2019

This article reports on the development of a Precipitation‐Hardenable‐Ferritic‐Pearlitic steel (PHFP steel) for energy‐efficient and distortion‐reduced production of cold‐formed, high‐strength structural components. Based on an alloying concept containing 0.8 wt% copper, a technology for the production of screws is developed to exploit the precipitation‐hardening effect of copper for increasing strength by ageing while avoiding final quenching.
Productivity of a preparative high‐performance liquid chromatography isolation of anacardic acids from cashew nut shell liquid
Authors: Oiram Filho Francisco , Zocolo Guilherme J. , Canuto Kirley M. , Silva Junior Ivanildo J. da , de Brito Edy S.
Published: April 2019

The anacardic acids are alkyl phenols, with biological activities, obtained as a byproduct from cashew nut processing. The anacardic acids isolation by preparative reversed phase high‐performance liquid chromatography was developed injecting large pulse from 50 to 200 mg of cashew nut shell liquid through a C18 column eluted with methanol, water and acetic acid (80:20:1). The separations were carried out at 25°C and monitored at 280 nm. Yield, recovery, purity, solvent consumption and productivity were analyzed. The results of anacardic acids isolation pointed the concentration loading of 100 mg as a process threshold leading to a productivity of 0.681 Kg.day−1.Kg−1 of anacardic acids with purity of 96.41, 95.32 and 90.77% for anacardic acid triene, diene and monoene, respectively.
Development of the thalamus: From early patterning to regulation of cortical functions
Authors: Nakagawa Yasushi
Published: April 2019

The thalamus is a brain structure of the vertebrate diencephalon that plays a central role in regulating diverse functions of the cerebral cortex. In traditional view of vertebrate neuroanatomy, the thalamus includes three regions, dorsal thalamus, ventral thalamus, and epithalamus. Recent molecular embryological studies have redefined the thalamus and the associated axial nomenclature of the diencephalon in the context of forebrain patterning. This new view has provided a useful conceptual framework for studies on molecular mechanisms of patterning, neurogenesis and fate specification in the thalamus as well as the guidance mechanisms for thalamocortical axons. Additionally, the availability of genetic tools in mice has led to important findings on how thalamic development is linked to the development of other brain regions, particularly the cerebral cortex. This article will give an overview of the organization of the embryonic thalamus and how progenitor cells in the thalamus generate neurons that are organized into discrete nuclei. I will then discuss how thalamic development is orchestrated with the development of the cerebral cortex and other brain regions.

This article is categorized under:

Nervous System Development > Vertebrates: Regional Development

Nervous System Development > Vertebrates: General Principles
Alignment of Multiple Perspectives: Establishing Common Ground for Triggering Organizational Change
Authors: Oppl Stefan , Stary Christian
Published: April 2019

This chapter introduces methodological support for transitioning from existing to envisioned work processes via direct actor involvement. It suggests direct actor involvement in the alignment and validation of novel work practices, in particular when digital workflows or instruments are involved that fundamentally impact the modes of individual operation and collaboration. Alignment is required for consolidating various inputs for further processing. In particular, actively involving process participants in process modeling creates a challenge for consolidated digital work design. Process participants are not expected to have modeling skills and usually, they prefer to externalize their knowledge through diagrams that are as simple as possible in terms of both syntax and semantics (‘natural modeling’). Alignment leads to accommodation of novel perspectives on a work process according to the participants’ individual mental models, allowing their implementation in organizational practice after validation.
Epilogue
Authors: Oppl Stefan , Stary Christian
Published: April 2019

The design of digital work systems requires stakeholder involvement in generating relevant work knowledge. It starts with articulation, and proceeds with sharing and aligning this knowledge in more or less structured design spaces. Once the ultimate goal is to develop executable processes in evolving systems, such as cyber-physical environments, specifications require stakeholders to become skilled in programming (concepts) for automated model execution. In this chapter, we demonstrate that models can be created on an abstract, implementation-independent level, while still being executable. The so-called ground models serve as boundary objects for iterative prototyping and interactive validation of specific process scenarios or situations. Remaining on this level of description allows tracing diagrammatic models while running their code, thus reducing system complexity to manageable components and architectures.
Gravitational resonances in mimetic thick branes
Authors: Zhong Yi , Zhang Yu-Peng , Guo Wen-Di , Liu Yu-Xiao
Published: April 2019

Abstract

In this work, we investigate gravitational resonances in both single and double mimetic thick branes, which can provide a new way to detect the extra dimension. For the single brane model, we apply the relative probability proposed in [Phys. Rev.
D 80 (2009) 065019]. For the double brane model, we investigate the resonances quasi-localized on the double brane, on the sub-branes and between the sub-branes, respectively. To investigate the resonances quasi-localized on the double brane, we introduce two different definitions of the relative probability and find that the corresponding mass spectra of gravitational resonances are almost the same. For the gravitational resonances quasi-localized on sub-branes and between the sub-branes, the influence of the distance between the two sub-branes and the thickness of the sub-branes are analyzed and new features are found in both cases.
Irreversibility in quantum field theories with boundaries
Authors: Casini Horacio , Landea Ignacio Salazar , Torroba Gonzalo
Published: April 2019

Abstract

We study conformal field theories with boundaries, and their boundary renormalization group (RG) flows, using methods from quantum information theory. Positivity of the relative entropy, together with unitarity and Lorentz invariance, give rise to bounds that characterize the irreversibility of such flows. This generalizes the recently proved entropic g-theorem to higher dimensions. In 2 + 1 dimensions with a boundary, we prove the entropic b-theorem — the decrease of the two-dimensional Weyl anomaly under boundary RG flows. In higher dimensions, the bound implies that the leading area coefficient of the entanglement entropy induced by the defect decreases along the flow. Our proof unifies these properties, and provides an information-theoretic interpretation in terms of the distinguishability between the short distance and long distance states. Finally, we establish a sum rule for the change in the area term in theories with boundaries, which could have implications for models with localized gravity.
Sarcopenia Affects Systemic and Local Immune System and Impacts Postoperative Outcome in Patients with Extrahepatic Cholangiocarcinoma
Authors: Kitano Yuki , Yamashita Yo‐ichi , Saito Yoichi , Nakagawa Shigeki , Okabe Hirohisa , Imai Katsunori , Komohara Yoshihiro , Miyamoto Yuji , Chikamoto Akira , Ishiko Takatoshi , Baba Hideo
Published: April 2019

Background

A decrease in skeletal muscle mass and function, defined as sarcopenia, is associated with poor postoperative outcome in patients with cancers. Although systemic or local immune status impacts cancer progression, the relationship between sarcopenia and these statuses remains unclear. The aim of this study is to investigate the clinical impact of sarcopenia and its relationship to immune systems in patients with extrahepatic cholangiocarcinoma (ECC).

Methods

A total of 110 consecutive ECC patients with curative resection between 2005 and 2014 were enrolled. Sarcopenia was determined from skeletal muscle index, assessed by a L3 skeletal muscle mass on axial computed tomography images, and their relationships with patients’ clinicopathological characteristics and survival were evaluated. Systemic immune status was calculated using preoperative laboratory data, and tumor‐infiltrating (TI) immune cells (CD8+ T cells, CD66b+ neutrophils, CD163+ M2 macrophages) assayed by immunohistochemistry, and their relationship to sarcopenia were evaluated.

Results

Sarcopenia was present in 31 patients (28.2%). Patients with sarcopenia had a worse recurrence‐free survival (HR 1.87, p = 0.009) and overall survival (OS) (HR 2.47, p = 0.0004) than patients without sarcopenia. Moreover, patients with sarcopenia had a higher level of platelet–lymphocyte ratio (159 vs. 119; p = 0.003) and lower number of TI CD8+ T cells (47 vs. 66 cells/spot; p = 0.03) than patients without sarcopenia. On multivariate analysis, the presence of sarcopenia (HR 2.60, p = 0.0008) was an independent predictor of poor OS.

Conclusions

Our data showed that sarcopenia and systemic or local immune cells may interact with each other and play a pivotal role in clinical outcomes of patients with ECC.
Looking Back in Anger? Retirement and Unemployment Scarring
Authors: Hetschko Clemens , Knabe Andreas , Schöb Ronnie
Published: April 2019

Unemployment affects future working conditions and job security negatively, thus reducing life satisfaction after reemployment. These employment-related scars of unemployment should not matter anymore when a person has retired. Using German panel data, we analyze unemployed persons’ transition into retirement to test whether unemployment leaves scars beyond working life and thus for reasons that are not employment-related. We find that involuntary unemployment between the last job and retirement causes a loss in life satisfaction after retirement. People who influenced or even initiated unemployment, by contrast, show no scarring. The scarring effect goes beyond what can be explained by the income loss originating from reduced pensions. It shows up independently of whether the unemployment spell directly before retirement was the only experience of unemployment in a person’s career, or whether she had also experienced unemployment at earlier times. We do not find evidence that early retirement or involuntary retirement are the reasons why formerly unemployed retirees display unemployment scarring.
Cumulative Risks of Multiple Criminal Justice Outcomes in New York City
Authors: Hepburn Peter , Kohler-Hausmann Issa , Zorro Medina Angela
Published: April 2019

Previous research has provided estimates of the cumulative risk of felony conviction and imprisonment in the United States. These experiences are, however, also the rarest; most of what happens in the criminal justice system occurs at the level of the misdemeanor rather than the felony. This article addresses our limited understanding of the scope of subfelony justice by providing estimates of the cumulative risk of several lower-level arrest outcomes for one jurisdiction: New York City. Because of excess life table events contributed by nonresidents of New York City, estimates are likely upwardly biased relative to the true values. Nonetheless, they allow us to (1) assess the cumulative risk of misdemeanor conviction and jail sentences and (2) determine to what extent those who enter the world of subfelony justice are distinct from those with felony or imprisonment records.
Sleep deprivation and the development of leadership and need for cognition during the college years
Authors: Chen Wei‐Lin , Chen Jen‐Hao
Published: April 2019

Introduction

The epidemic of sleep deprivation among college students is alarming. Prior studies of college students' sleep deprivation have focused on academic outcomes and mental health problems. This study considers the impact of college students’ sleep deprivation on two key, developmental outcomes: leadership and need for cognition.

Methods

This study is a secondary analysis of longitudinal data from the Wabash National Study of Liberal Arts Education (N = 3,690), using random‐effects and fixed‐effects models to estimate the association between chronic sleep deprivation from freshman year to senior year and developmental outcomes.

Results

Results from the random‐effects model show that chronic sleep deprivation is negatively associated with lower scores in leadership skills () and need for cognition (), after accounting for potential confounders. Results from the fixed‐effects model that accounts for time‐invariant unobserved variables show similar patterns for leadership skills () and need for cognition ().

Conclusions

This study demonstrates that chronic sleep deprivation has consequences for critical skills, suggesting that steps to promote college students’ sleep health may also enhance their positive development in leadership skills and need for cognition.
Preventing adolescent suicide: A systematic review of the effectiveness and change mechanisms of suicide prevention gatekeeping training programs for teachers and parents
Authors: Torok M. , Calear A.L. , Smart A. , Nicolopoulos A. , Wong Q.
Published: April 2019

Introduction

Suicide is a leading cause of death in young people, which may in part be because young people are notoriously poor help‐seekers. Improving the identification of at‐risk young people and connecting them to appropriate help is needed to prevent suicide in adolescents. The aim of this study is to examine the effectiveness of suicide prevention gatekeeper programs for parents and teachers, which are designed to improve their ability to recognise and respond to risks so that they may intervene before crisis occurs.

Methods

Academic databases and reference lists were searched for gatekeeper training programs involving teachers and parents, and which aimed to prevent youth suicide, between journal inception and May 2018. Information directly reporting on suicide literacy (knowledge, confidence, attitudes) and/or gatekeeper behaviours (identification, referral) was extracted and a qualitative synthesis was conducted.

Results

Thirteen studies fulfilled inclusion criteria. Significant moderate‐to‐large intervention effects were reported for suicide literacy outcomes among teachers and parents, with the largest gains among those with lowest baseline scores. No improvements in identification and referral behaviors among gatekeepers were noted. A need to improve evaluation research designs and outcome measurements was evident.

Conclusions

While gatekeeper programs lead to increased suicide literacy, there is little evidence for behavioural change. There is need to increase the reach and uptake of gatekeeper training by offering digital versions, which may lead to improved behavioural outcomes, and to employ targeted strategies to engage parents in this training as one of the most trusted sources of support for vulnerable youth.
Should We Tailor the Clinical Management of Erectile Dysfunction According to Different Ages?
Authors: Capogrosso Paolo , Ventimiglia Eugenio , Boeri Luca , Pozzi Edoardo , Chierigo Francesco , Schifano Nicolò , Abbate Costantino , Matloob Rayan , Montorsi Francesco , Salonia Andrea
Published: April 2019

Introduction

The impact of erectile dysfunction (ED) on patients’ sexual satisfaction and mood profile could differ across different ages.

Aim

To investigate the relationship between erectile function (EF), sexual satisfaction, and mood status among patients seeking medical help for ED.

Methods

Data from 765 patients presenting at a single center for ED were analyzed. Patients were categorized as young (≤50 years), middle-aged (>50 and ≤65 years), and old (>65 years) individuals and completed the International Index of Erectile Function (IIEF) and the Beck’s Inventory for Depression (BDI).

Main Outcome Measures

The IIEF overall satisfaction and intercourse satisfaction domain scores and the BDI score were used to investigate sexual life satisfaction and depressive symptoms (defined as BDI > 11) across ages and according to ED severity. Linear and logistic regression analyses assessed the relationship between satisfaction scores and the risk of depressive symptoms with age and EF.

Results

Median (interquartile range) age at first assessment for ED was 50 (38, 59) years. Compared with older men, young and middle-aged patients showed significantly higher IIEF-OS and IIEF– Intercourse Satisfaction scores for increasing IIEF-EF scores. Older men showed no difference in terms of satisfaction scores for mild ED and normal EF status. At linear regression analysis, both IIEF-EF and age were significantly associated with sexual satisfaction (all P < .0001). The interaction term between age and EF was also significant, suggesting that the older the patients, the higher the feeling of sexual satisfaction for the same EF status (P = .004). Overall, 25% of patients reported depressive symptoms. Logistic regression analysis showed a 40% risk of depressive symptoms for patients <45 years with severe ED compared to a risk <20% for a man >65 years of age with the same EF status.

Clinical Implications

Treating older patients with mild ED may not lead to a further improvement in sexual satisfaction as compared with younger patients with the same ED severity. Younger ED patients suffer more from depressive symptoms compared with older men, regardless of ED severity, thus supporting the need for a comprehensive psychological counseling.

Strength & Limitations

The single-center design and the lack of the assessment of the impact of ED treatment are the main limits.

Conclusions

The clinical management of ED should be tailored according to different ages: younger patients deserve to be investigated and eventually treated for depressive symptoms. Older patients should be counseled for treatment when a sexual satisfaction improvement is expected.
A model of lipid dysregulation and altered nutrient status in Alzheimer's disease
Authors: Fluegge Keith
Published: April 2019

Introduction

Dysregulated lipid metabolism and nutrient status are thought to play a role in the pathophysiology of Alzheimer's disease (AD). However, the precise involvement is not well understood, and it remains unclear exactly how such dysregulated lipid metabolism and altered nutrient status, especially changes in phosphatidylcholine, B12, and folate, are connected to the hallmark pathology in AD (i.e., amyloidogenesis).

Methods

We have postulated that genetic susceptibility (i.e., APOE ε4/ε4) to environmental exposure to emissions of nitrous oxide (N2O) could underlie the onset of AD and its early neuropsychiatric correlates

Results and Discussion

The current theoretical editorial describes, using clinical, preclinical, and in vitro evidences, how this model contributes not only to amyloidogenesis but also other nonopioid effects, specifically altered lipid metabolism, depletion of vitamin B12, and disruption of the folate‐mediated one carbon metabolic pathway.
Combustion instability characteristics in a dump combustor using different hydrocarbon fuels
Authors: Hwang D. , Song Y. , Ahn K.
Published: April 2019

The combustion instability characteristics in a model dump combustor with an exhaust nozzle were experimentally investigated. The first objective was to understand the effects of operating conditions and geometric conditions on combustion instability. The second objective was to examine more generalised parameters that affect the onset of combustion instability. Three different premixed gases consisting of air and hydrocarbon fuels (C2H4, C2H6, C3H8) were burnt in the dump combustor at various inlet velocity, equivalence ratio and combustion chamber length. Dynamic pressure transducer and photomultiplier tube with a bandpass filter were used to measure pressure fluctuation and CH* chemiluminescence data. Peak frequencies and their maximum power spectral densities of pressure fluctuations at same equivalence ratios showed different trends for each fuel. However, the dynamic combustion characteristics of pressure fluctuations displayed consistent results under similar characteristics chemistry times regardless of the used hydrocarbon fuels. The results showed that characteristic chemistry time and characteristic convection time influenced combustion instabilities. It was found that the convective-acoustic combustion instability could be prevented by increasing the characteristic chemistry time and characteristic convection time.
Band-stop angular filtering with hump volume Bragg gratings
Authors: Gao Fan , Wang Xin , Yu Tiancheng , Zhang Xiang , Yuan Xiao
Published: April 2019

A band-stop angular filter (BSF) based on hump volume Bragg gratings (HVBGs) is proposed. Band-stop filtering in a two-stage amplifier laser system is discussed and simulated. Simulation results show that small-scale self-focusing effects in the laser system can be effectively suppressed with the BSF due to the control of fast nonlinear growth in a specific range of spatial frequencies in the laser beam. Near-field modulation of the output beam from the laser system was decreased from 2.69 to 1.37 by controlling the fast nonlinear growth of spatial frequencies ranging from $0.6~\text{mm}^{-1}$ to $1.2~\text{mm}^{-1}$ with the BSF. In addition, the BSF can be used in a plug-and-play scheme and has potential applications in high-power laser systems.
Pulmonary artery catheter epidemiology of risk in pre–heart-transplant recipients
Authors: Yetmar Zachary A , Lahr Brian , O’Horo John , Behfar Atta , Sampathkumar Priya , Beam Elena
Published: April 2019

Objective:

Central-line–associated bloodstream infections (CLABSIs) are a known complication of central venous access. Pulmonary artery catheters (PAC) are frequently used in pre–heart-transplant patients, but the rate of CLABSI in this population is unknown. We sought to estimate the rate of CLABSI and identify factors associated with development of infection in patients actively listed for heart transplantation with a PAC.

Design:

Retrospective cohort study.

Setting:

This study was conducted in 3 intensive care units at an academic tertiary-care center in Minnesota.

Patients:

61 pre–heart-transplant patients in an intensive care unit with a PAC in place from January 2013 to December 2016, totaling 219 PACs.

Methods:

At-risk patients, pertinent risk factors, and demographic data were obtained using Mayo Clinic’s Unified Data Platform. CLABSIs were identified through internal infection prevention and control data. Characteristics of PAC use and infection rate were collected and analyzed using Kaplan-Meier estimates and time-dependent Cox models.

Results:

Among pre–heart-transplant patients with a PAC, there were 14 CLABSIs, for an infection rate of 5.46 of 1,000 PAC days (95% confidence interval [CI], 2.98–9.15). The most common causative organism was coagulase-negative Staphylococcus (79%). In unadjusted analyses, CLABSI was associated with shorter time to transplant (hazard ratio [HR], 2.49; P = .027), but not mortality (HR, 1.79; P = .355).

Conclusions:

The rate of CLABSI with PAC is high. Prolonged PAC use in the pre–heart-transplant population should be revisited.
Non-canonical Hamiltonian structure and Poisson bracket for two-dimensional hydrodynamics with free surface
Authors: Dyachenko A. I. , Lushnikov P. M. , Zakharov V. E.
Published: April 2019

We consider the Euler equations for the potential flow of an ideal incompressible fluid of infinite depth with a free surface in two-dimensional geometry. Both gravity and surface tension forces are taken into account. A time-dependent conformal mapping is used which maps the lower complex half-plane of the auxiliary complex variable $w$ into the fluid’s area, with the real line of $w$ mapped into the free fluid’s surface. We reformulate the exact Eulerian dynamics through a non-canonical non-local Hamiltonian structure for a pair of the Hamiltonian variables. These two variables are the imaginary part of the conformal map and the fluid’s velocity potential, both evaluated at the fluid’s free surface. The corresponding Poisson bracket is non-degenerate, i.e. it does not have any Casimir invariant. Any two functionals of the conformal mapping commute with respect to the Poisson bracket. The new Hamiltonian structure is a generalization of the canonical Hamiltonian structure of Zakharov (J. Appl. Mech. Tech. Phys., vol. 9(2), 1968, pp. 190–194) which is valid only for solutions for which the natural surface parametrization is single-valued, i.e. each value of the horizontal coordinate corresponds only to a single point on the free surface. In contrast, the new non-canonical Hamiltonian equations are valid for arbitrary nonlinear solutions (including multiple-valued natural surface parametrization) and are equivalent to the Euler equations. We also consider a generalized hydrodynamics with the additional physical terms in the Hamiltonian beyond the Euler equations. In that case we identify powerful reductions that allow one to find general classes of particular solutions.
Diffusion of inertia-gravity waves by geostrophic turbulence
Authors: Kafiabad Hossein A. , Savva Miles A. C. , Vanneste Jacques
Published: April 2019

The scattering of inertia-gravity waves by large-scale geostrophic turbulence in a rapidly rotating, strongly stratified fluid leads to the diffusion of wave energy on the constant-frequency cone in wavenumber space. We derive the corresponding diffusion equation and relate its diffusivity to the wave characteristics and the energy spectrum of the turbulent flow. We check the predictions of this equation against numerical simulations of the three-dimensional Boussinesq equations in initial-value and forced scenarios with horizontally isotropic wave and flow fields. In the forced case, wavenumber diffusion results in a $k^{-2}$ wave energy spectrum consistent with as-yet-unexplained features of observed atmospheric and oceanic spectra.
Late Pleistocene marine resources from the Bering Glacier Foreland and human coastal migration in the northern Gulf of Alaska region
Authors: Yesner David R. , Pasch Anne D. , Crossen Kristine J.
Published: April 2019

Recent research on the Bering Glacier forelands in the northern Gulf of Alaska provides new insights into late Pleistocene/early Holocene shorelines, providing a favorable route for human migration as early as ~16,000 cal yr BP. This route included an irregular coastline with embayments and islands offering protection from the open ocean; edible marine invertebrates dating from 15,000 to 5,500 cal yr BP; and marine vertebrates dating as early as 16,000 cal yr BP. The latter included walrus (Odobenus rosmarus), bearded seal (Erignathus barbatus), and ringed seal (Phoca cf. hispida), all associated with pack ice conditions unlike those present today. While this ecosystem could have supported humans migrating along the coastline, and coastal refugia may have existed elsewhere in the region, coastal archaeological sites in the northern Gulf of Alaska and southwest Alaska are no older than ~9,500 cal yr BP. This suggests that the earliest sites have been eroded or destroyed, that the earliest migrants ignored available marine resources, and/or that these migrants did not use a coastal route. In contrast, the earliest archaeological sites in southeast Alaska date to ~12,500 cal yr BP, suggesting migration from interior Alaska to the coast somewhere east of the Copper River delta.
Law and War in the Virtual Era
Authors: Beard Jack M.
Published: April 2019

Since the first attempts by states to use law to regulate armed conflict, legal constraints have often failed to protect civilians from the adverse effects of war. Advances in military technology have usually not improved this situation and have instead made law even more distant and less relevant to the suffering of civilians in wartime. The massive, indiscriminate incendiary bombing campaigns against major urban areas in World War II spoke volumes about the irrelevance of fundamental legal principles and rules designed to protect civilian populations in wartime. Law and lawyers were in fact far removed, physically and operationally, from the cockpits of the United States bombers flying over Tokyo, whose aircrews were focused on surviving their missions. They struggled with limited information about their assigned targets and conducted their operations with rudimentary preflight instructions that directed them, for example, to avoid destroying the palace of the Japanese emperor but left them free to submerge entire residential areas of the city in a sea of flames.
The Pillar of Glass: Human Rights in the Development Operations of the United Nations
Authors: Darrow Mac , Arbour Louise
Published: April 2019

In September 2007, Buddhist monks, students, democracy campaigners, and ordinary men, women, and children took their lives into their hands in the streets of Yangon, Myanmar, to protest against the ruling military regime. The protests had begun a month earlier with peaceful calls by the monks for the ruling authorities to reinstate subsidies on fuel and oil and alleviate crippling commodity prices, but quickly snowballed into mass demonstrations for democratic and social reforms and the release of all political prisoners.
Why does Aristotle think bees are divine? Proportion, triplicity and order in the natural world
Authors: LEHOUX DARYN
Published: April 2019

Concluding his discussion of bee reproduction in Book 3 ofGeneration of Animals, Aristotle makes a famous methodological pronouncement about the relationship between sense perception and theory in natural history. In the very next sentence, he casually remarks that the unique method of reproduction that he finds in bees should not be surprising, since bees have something ‘divine’ about them. Although the methodological pronouncement gets a fair bit of scholarly attention, and although Aristotle's theological commitments in cosmology and metaphysics are well known, scholars have almost universally passed over the comment about bees and divinity in silence. This paper aims to show why that comment is no mere throwaway, and offers an exploration and elaboration of the ways in which divinity operates even at fairly mundane levels in his natural philosophy, as an important Aristotelian explanation for order, proportion and rationality, even in the lowest of animals.
PARABOLIC SUBROOT SYSTEMS AND THEIR APPLICATIONS
Authors: BURNS JOHN M. , MAKROONI MOHAMMAD A.
Published: April 2019

In this note we consider parabolic subroot systems of a complex simple Lie Algebra. We describe root theoretic data of the subroot systems in terms of that of the root system and we give a selection of applications of our results to the study of generalized flag manifolds.
Comparison of an on-farm point-of-care diagnostic with conventional culture in analysing bovine mastitis samples
Authors: Jones Geoff , Bork Olaf , Ferguson Scott A , Bates Andrew
Published: April 2019

The performance of a new point-of-care diagnostic (Mastatest), an on-farm test designed to identify bacteria and provide antibiotic sensitivity testing information from milk samples, was compared with standard microbiological culture methods. A total of 292 milk samples from clinical mastitis cases in dairy cows on New Zealand dairy farms were examined, and latent class analysis was used to estimate the performance characteristics of both tests. Two hundred and fifty-six samples (87.7%) demonstrated bacterial infection in standard culture, and 269 (92.1%) using the point-of-care diagnostic. The most common bacterial species detected was Streptococcus uberis, found in 195 samples (66.8%) using standard culture and 190 samples (65.1%) using the point-of-care diagnostic. Latent class analysis found no significant differences in test characteristics between the point-of-care diagnostic and standard culture. The estimated sensitivity and specificity of the point-of-care diagnostic against all targets combined were 94.6 and 72.1% respectively; the corresponding estimates for standard culture were 90.5 and 73.9%. Comparison of antibiotic susceptibility testing using the point-of-care diagnostic and the reference method showed similar trends and, in some cases, identical MIC50 and MIC90 values, with at most one antibiotic dilution difference.
Milk β-hydroxybutyrate concentration measured by Fourier-transform infrared and flow-injection analyses from samples taken at different times relative to milking
Authors: Duplessis Mélissa , Santschi Débora E. , Plante Sabrina , Bergeron Camille , Lefebvre Daniel M. , Durocher Jean , Cue Roger I.
Published: April 2019

Analysis of milk BHB concentration by Fourier-transform infrared (FTIR) spectrometry more frequently than regular milk testing could help dairy producers in decision making, particularly if it would be possible to use small hand-stripped samples (hereinafter simply called samples) taken between dairy herd improvement (DHI) test-samples analysed using DHI algorithms. The aim of this Research Communication was to evaluate milk BHB concentration and the prevalence of elevated milk BHB concentration analysed by FTIR spectrometry compared with flow-injection analysis (SKALAR) from samples taken at different times relative to the milking. A total of 293 early-lactation cows in 44 commercial dairy herds were involved in the study. Herds were visited once during the morning milking when a routine DHI test-sample was obtained using in-line milk samplers. Additional milk samples were taken by hand stripping as follows: (1) Just before connecting the milking machine; (2) immediately after removing the milking machine; (3) 3 h after milking and (4) 6 h after milking. Milk samples were analysed for BHB concentration by FTIR and SKALAR, the latter being the reference method. Milk BHB concentration from samples taken before milking was different between FTIR and SKALAR whereas no difference was noted for other sampling times, although milk BHB concentration rose as time after milking increased. Except for DHI test-samples for which prevalence was not different between analysis methods, prevalence of elevated milk BHB concentration (≥0.15 mmol/l) was greater for FTIR analysis. However, no difference in prevalence was observed between SKALAR and FTIR when using a threshold of ≥0.20 mmol/l. In summary, hand-stripped milk samples taken any time after removing the milking machine until 6 h after the milking can be recommended for FTIR analysis of elevated milk BHB concentration prevalence provided a threshold of 0.20 mmol/l is used.
Analysis of fatty acid profile in milk fat of Wallachian sheep during lactation
Authors: Ptáček Martin , Milerski Michal , Ducháček Jaromír , Schmidová Jitka , Tančin Vladimír , Uhrinčať Michal , Stádník Luděk , Michlová Tereza
Published: April 2019

In this Research Communication we evaluate the fatty acid (FA) profile of Wallachian sheep milk. The study was performed on 38 ewes in Beskydy Mountains. Samples were collected 4 times during the lactation, at monthly intervals. FA profile as well as groups of saturated, monounsaturated (MUFA), and polyunsaturated (PUFA) FAs were investigated. Considerable increase over the lactation was detected for lauric, myristic, myristoleic and palmitic acids, while stearic acid showed the opposed tendency. Variability, supported by significant differences among particular days of milk collection, was demonstrated for oleic acid; its highest distribution occurred at the beginning and at the end of the trial. The highest distribution of CLA was at the second sample day. Milk of Wallachian sheep naturally grazed at permanent pasture areas showed higher content of PUFA and MUFA in contrast with intensive or semi-intensive sheep breeds reported in the literature.
Financial Incentives and Loan Officer Behavior: Multitasking and Allocation of Effort under an Incomplete Contract
Authors: Behr Patrick , Drexler Alejandro , Gropp Reint , Guettler Andre
Published: April 2019

We investigate the implications of providing loan officers with a nonlinear compensation structure that rewards loan volume and penalizes poor performance. Using a unique data set provided by a large international commercial bank, we examine the main activities that loan officers perform: loan prospecting, screening, and monitoring. We find that when loan officers are at risk of losing their bonuses, they increase prospecting and monitoring. We further show that loan officers adjust their behavior more toward the end of the month when bonus payments are approaching. These effects are more pronounced for loan officers with longer tenures at the bank.
Individual Commitment and Team Performance: Evidence from Mutual Fund Managers
Authors: Luo Jiang , Qiao Zheng
Published: April 2019

The psychology literature suggests that individual commitment has a positive effect on team performance by mitigating the free-rider problem. With its detailed management-team information, the mutual fund industry provides a unique opportunity to study how individual managerial commitment is related to performance. Committed fund managers are defined as those who work only for one fund. With few incentives to acquire private information, teams with no committed members underperform those with committed members. These findings remain robust after we incorporate various controls. We also explore why non-committed teams have been used increasingly often despite their poor performance.
A computer simulation of language families
Authors: DE OLIVEIRA PAULO MURILO CASTRO , STAUFFER DIETRICH , WICHMANN SØREN , DE OLIVEIRA SUZANA MOSS
Published: April 2019

This paper presents computer simulations of language populations and the development of language families, showing how a simple model can lead to distributions similar to those observed empirically by Wichmann (2005) and others. The model combines features of two models used in earlier work for the simulation of competition among languages: the ‘Viviane’ model for the migration of peoples and the propagation of languages, and the ‘Schulze’ model, which uses bit-strings as a way of characterising structural features of languages.
Cultures de l'écrit en Afrique. Anciens débats, nouveaux objets
Authors: Ficquet Éloi
Published: April 2019

Ce dossier consacré aux cultures écrites en Afriqueentend ouvrir une fenetre sur les connaissances produites sur et a partir des sociétés africaines en se concentrant sur un objet transversal qui présente la caractéristique de ne pas etre traumatique, contrairement aux questions par lesquelles les problématiques concernant l’Afrique sont généralement posées (l’esclavage, les migrations, les crises humanitaires, les faillites politiques, etc.). Il s’agit d’explorer plusieurs formes et usages de l’écrit en Afrique et de les mettre en perspective selon différentes approches.

Ce theme pourrait apparaître comme un combat de plus contre une des nombreuses idées reçues au sujet de ce continent, celle selon laquelle la plupart des sociétés d’Afrique au sud du Sahara auraient ignoré l’usage de l’écriture et se seraient par conséquent privées d’un instrument de transmission et de transformation cognitive et sociale. Les preuves a l’encontre de cette conception qui a la vie dure ne sont plus d’une grande nouveauté. L’enjeu des travaux sur l’écrit en Afrique n’est plus la et c’est ce que ce dossier veut montrer. Ces toutes dernieres années, des séries significatives de découvertes d’objets inédits, de déplacements de pistes de recherches, d’échanges interdisciplinaires se sont produites dans les « humanités africaines ».