bluuebunny/crossref_metadata_2025 huggingface dataset:
Developmental variability channels mouse molar evolution
Authors: Hayden Luke , Lochovska Katerina , Sémon Marie , Renaud Sabrina , Delignette-Muller Marie-Laure , Vilcot Maurine , Peterkova Renata , Hovorakova Maria , Pantalacci Sophie
Published: February 2020

Do developmental systems preferentially produce certain types of variation that orient phenotypic evolution along preferred directions? At different scales, from the intra-population to the interspecific, the murine first upper molar shows repeated anterior elongation. Using a novel quantitative approach to compare the development of two mouse strains with short or long molars, we identified temporal, spatial and functional differences in tooth signaling center activity, that arise from differential tuning of the activation-inhibition mechanisms underlying tooth patterning. By tracing their fate, we could explain why only the upper first molar reacts via elongation of its anterior part. Despite a lack of genetic variation, individuals of the elongated strain varied in tooth length and the temporal dynamics of their signaling centers, highlighting the intrinsic instability of the upper molar developmental system. Collectively, these results reveal the variational properties of murine molar development that drive morphological evolution along a line of least resistance.
Overtone focusing in biphonic tuvan throat singing
Authors: Bergevin Christopher , Narayan Chandan , Williams Joy , Mhatre Natasha , Steeves Jennifer KE , Bernstein Joshua GW , Story Brad
Published: February 2020

Khoomei is a unique singing style originating from the republic of Tuva in central Asia. Singers produce two pitches simultaneously: a booming low-frequency rumble alongside a hovering high-pitched whistle-like tone. The biomechanics of this biphonation are not well-understood. Here, we use sound analysis, dynamic magnetic resonance imaging, and vocal tract modeling to demonstrate how biphonation is achieved by modulating vocal tract morphology. Tuvan singers show remarkable control in shaping their vocal tract to narrowly focus the harmonics (or overtones) emanating from their vocal cords. The biphonic sound is a combination of the fundamental pitch and a focused filter state, which is at the higher pitch (1–2 kHz) and formed by merging two formants, thereby greatly enhancing sound-production in a very narrow frequency range. Most importantly, we demonstrate that this biphonation is a phenomenon arising from linear filtering rather than from a nonlinear source.
An effective survey method for studying volant species activity and behavior at tall structures
Authors: Huzzen Brynn E. , Hale Amanda M. , Bennett Victoria J.
Published: February 2020

The effects of anthropogenic modification of air space on wildlife, particularly volant species, is not fully understood. Thus, it is essential to understand wildlife-interactions with tall structures to implement effective mitigation strategies. Yet, we are currently lacking standard protocols for visual surveys of wildlife behavior at such heights. Our study sought to determine an effective, repeatable method using readily available night vision and thermal technology to survey wildlife at tall structures. Using bats as the taxonomic group of interest, we (1) created a key to identify bats and their behavior, (2) compared the effectiveness of 2 different technologies, and (3) assessed optimal equipment placement to visually capture bat activity and behavior in proximity to wind turbine towers. For the latter, we tested thermal cameras at four distances from the base of the tower. The results of our study revealed that thermal cameras captured ∼34% more flying animals than night vision at a 2 m distance. However, due to the heat signature of the turbine towers themselves, it was challenging to identify behaviors and interactions that occurred in close proximity to the towers. In contrast, it was difficult to identify bats approaching the towers using night vision, yet we were able to clearly observe interactions with the towers themselves. With regards to equipment placement, we visually captured more bats with the thermal cameras placed 2 m from the tower base compared to farther distances. From our findings, we recommend that when using either thermal or night vision technology at tall structures, they be placed 2 m from the base to effectively observe interactions along the length of these structures. In addition, we further recommend that consideration be given to the use of these two technology types together to effectively conduct such surveys. If these survey techniques are incorporated into standard protocols, future surveys at a variety of tall structures are likely to become comparable and repeatable, thereby more effectively informing any mitigation strategies that may be required.
The N-terminal domain of rhamnosyltransferase EpsF influences exopolysaccharide chain length determination in Streptococcus thermophilus 05-34
Authors: Wang Guohong , Li Jiaxi , Xie Shuxin , Zhai Zhengyuan , Hao Yanling
Published: February 2020

Glycosyltransferases are key enzymes involved in the assembly of repeating units of exopolysaccharides (EPS). A glycosyltransferase generally consists of the N-terminal and the C-terminal domain, however, the functional role of these domains in EPS biosynthesis remains largely unknown. In this study, homologous overexpression was employed to investigate the effects of EpsFN, a truncated form of rhamnosyltransferase EpsF with only the N-terminal domain, on EPS biosynthesis in Streptococcus thermophilus 05-34. Reverse transcription qPCR and Western blotting analysis confirmed the successful expression of epsFN in 05-34 at the transcription and translation level, respectively. Further analysis showed that the monosaccharide composition and yield of EPS were not affected by the overexpression of epsFN, whereas the molecular mass decreased by 5-fold. Accordingly, the transcription levels of genes involved in EPS biosynthesis, including chain-length determination gene epsC, were down-regulated by 5- to 6-fold. These results indicated that the N-terminal domain of EpsF alone could influence the molecular mass of EPS, probably via lowering the concentration of sugar precursors, which may lead to decreased expression of genes responsible for chain-length determination.
In silico analysis of maize HDACs with an emphasis on their response to biotic and abiotic stresses
Authors: Zhang Kang , Yu Lu , Pang Xi , Cao Hongzhe , Si Helong , Zang Jinping , Xing Jihong , Dong Jingao
Published: February 2020

Histone deacetylases (HDACs) are key epigenetic factors in regulating chromatin structure and gene expression in multiple aspects of plant growth, development, and response to abiotic or biotic stresses. Many studies on systematic analysis and molecular function of HDACs in Arabidopsis and rice have been conducted. However, systematic analysis of HDAC gene family and gene expression in response to abiotic and biotic stresses has not yet been reported. In this study, a systematic analysis of the HDAC gene family in maize was performed and 18 ZmHDACs distributed on nine chromosomes were identified. Phylogenetic analysis of ZmHDACs showed that this gene family could be divided into RPD3/HDA1, SIR2, and HD2 groups. Tissue-specific expression results revealed that ZmHDACs exhibited diverse expression patterns in different tissues, indicating that these genes might have diversified functions in growth and development. Expression pattern of ZmHDACs in hormone treatment and inoculation experiment suggested that several ZmHDACs might be involved in jasmonic acid or salicylic acid signaling pathway and defense response. Interestingly, HDAC genes were downregulated under heat stress, and immunoblotting results demonstrated that histones H3K9ac and H4K5ac levels were increased under heat stress. These results provide insights into ZmHDACs, which could help to reveal their functions in controlling maize development and responses to abiotic or biotic stresses.
INFLUÊNCIA DOS BANCOS PÚBLICOS NO SPREAD BANCÁRIO BRASILEIRO
Authors: Figueiredo Rafael Borges de , Dantas José Alves
Published: February 2020

Os níveis das taxas de juros praticadas em uma economia são considerados como indicativos da eficiência da intermediação financeira que pode gerar ambiente propício para o desenvolvimento regional ou nacional. No Brasil as altas taxas de spread praticadas são foco de intensos debates que ocasionam críticas às rentabilidades auferidas pelos bancos além de pesquisas sobre as estruturas dos determinantes do spread bancário. A maior parte da literatura se debruça sobre a identificação dos determinantes sob a métrica ex ante de análise do spread. Este estudo busca identificar a influência dos bancos públicos no nível do spread bancário sob a métrica ex post. Utilizando dados em painel dos balancetes trimestrais desde o primeiro trimestre de 2008 ao quarto trimestre de 2017, dados disponibilizados pelo Banco Central do Brasil das instituições bancárias individuais, foram testadas duas hipóteses e quatro variáveis de controle que constataram que o nível de spread ex post tem relação estatística significativa e positiva com: risco de crédito, variação da atividade econômica (PIB) e agregados de bancos públicos; relação estatística negativa com o porte da carteira de crédito e taxa básica de juros (Selic) e a taxa de juros real.
Nominata de Avaliadores
Authors: Marcelino Carolina Venturini
Published: February 2020

Nominata de Avaliadores 2019
Promoting Energy Efficiency via a Self‐Adaptive Evaporative Cooling Hydrogel
Authors: Pu Shirui , Fu Jia , Liao Yutian , Ge Lurong , Zhou Yihao , Zhang Songlin , Zhao Shenlong , Liu Xiaowei , Hu Xuejiao , Liu Kang , Chen Jun
Published: February 2020

High temperature brings adverse impacts on the energy efficiency, and even destroys a semiconductor device. Here, a novel and cost‐effective strategy is proposed to boost the energy efficiency of semiconductor devices by using the self‐adaptive evaporative cooling of a lithium‐ and bromine‐enriched polyacrylamide hydrogel. Water inside the hydrogel can quickly evaporate to dissipate the waste heat generated by the nugatory carrier transport in the P‐N junction. In dormancy, the hydrogel harvests water molecules from the surrounding air to regenerate itself. The hydrogel is demonstrated to low down the operating temperature of a commercial polycrystalline silicon solar cell by 17 °C under one sun condition and enhances its efficiency from 14.5% to 15.5%. It is also capable of increasing the maximum power of a simulated chip by 45% at a fixed operating temperature. The hydrogel is expected to be widely adopted in current semiconductor industry to improve its energy efficiency.
Beyond Ternary OPV: High‐Throughput Experimentation and Self‐Driving Laboratories Optimize Multicomponent Systems
Authors: Langner Stefan , Häse Florian , Perea José Darío , Stubhan Tobias , Hauch Jens , Roch Loïc M. , Heumueller Thomas , Aspuru‐Guzik Alán , Brabec Christoph J.
Published: February 2020

Fundamental advances to increase the efficiency as well as stability of organic photovoltaics (OPVs) are achieved by designing ternary blends, which represents a clear trend toward multicomponent active layer blends. The development of high‐throughput and autonomous experimentation methods is reported for the effective optimization of multicomponent polymer blends for OPVs. A method for automated film formation enabling the fabrication of up to 6048 films per day is introduced. Equipping this automated experimentation platform with a Bayesian optimization, a self‐driving laboratory is constructed that autonomously evaluates measurements to design and execute the next experiments. To demonstrate the potential of these methods, a 4D parameter space of quaternary OPV blends is mapped and optimized for photostability. While with conventional approaches, roughly 100 mg of material would be necessary, the robot‐based platform can screen 2000 combinations with less than 10 mg, and machine‐learning‐enabled autonomous experimentation identifies stable compositions with less than 1 mg.
Recent Progress in Chemiresistive Gas Sensing Technology Based on Molybdenum and Tungsten Chalcogenide Nanostructures
Authors: Jha Ravindra Kumar , Bhat Navakanta
Published: February 2020

Chalcogens are oxygen family elements with oxygen having distinct properties than the other group members like sulfur, selenium, and tellurium. Tungsten and molybdenum chalcogenides that include mainly metal oxides (MO3; M = Mo, and W) and metal dichalcogenides (MX2; X = S, Se, and Te) are the most exciting class of inorganic materials. They have been widely investigated in various applications including lithium and sodium ion storage, supercapacitors, gas sensors, biosensors etc. due to their fascinating surface properties and ease of fabrication. Different class of nanostructures including 0D (nanoparticles, quantum dots), 1D (nanowires, nanotubes, nanoribbons, nanobelts etc.), and 2D (nanosheets, nanoflakes, nanoplates etc.) structures of these materials have been synthesized, characterized, and utilized for these applications. With recent boost in layered material research, they are also being reconsidered for future device and systems applications. In this review article, the recent developments on the chemiresistive gas sensing applications of these nanomaterials are discussed. The authors also outline the efforts which have been made over the years to improve the sensing behavior of these materials. Finally, the authors present future opportunities in realizing high‐performance gas sensors using these materials.
Recent Advances in Polymer Electrolytes for Zinc Ion Batteries: Mechanisms, Properties, and Perspectives
Authors: Wu Kai , Huang Jianhang , Yi Jin , Liu Xiaoyu , Liu Yuyu , Wang Yonggang , Zhang Jiujun , Xia Yongyao
Published: February 2020

Aqueous rechargeable zinc ion batteries (ZIBs) have been deemed to be possible candidates for large‐scale energy storage due to their ecoefficiency, substantial reserve, safety, and low cost. However, the challenges inherent in aqueous electrolytes, such as water splitting reactions, water evaporation, and liquid leakage, have greatly hindered their development in energy storage. Fortunately, polymer electrolytes would be able to overcome the abovementioned challenges. Moreover, the flexible properties of polymer electrolytes can facilitate their future application in wearable electronics. Recently, increasing attention has been attracted to the polymer electrolyte‐based zinc ion batteries. However, the development of polymer electrolytes for ZIBs is still in the early stages due to numerous challenges. Therefore, substantial research effort is required to overcome the challenges of polymer electrolyte‐based ZIBs. In this review, the current progress in developing polymer electrolytes, including solid polymer electrolytes, gel polymer electrolytes, and hybrid polymer electrolytes, as well as the interactions between electrodes and polymer electrolytes for ZIBs is comprehensively reviewed, analyzed, and discussed in terms of their synthesis, characterization, and performance validation. To facilitate further research and development of polymer electrolytes for ZIBs, the relevant challenges are summarized and analyzed, and some underlying approaches to overcome these challenges are also proposed.
Electronic Contact Lens: A Platform for Wireless Health Monitoring Applications
Authors: Yuan Mengyao , Das Rupam , Ghannam Rami , Wang Yinhao , Reboud Julien , Fromme Roland , Moradi Farshad , Heidari Hadi
Published: February 2020

Electronic contact lenses are used for noninvasively monitoring vital human signs and medical parameters. However, maintaining a secure communications connection and a self‐sustainable power source are still looming challenges. Herein, a proof‐of‐concept electronic contact lens is demonstrated that includes a spiral antenna with its wireless circuit unit for data telemetry, a rectifier circuit for power conditioning, and a micro‐light‐emitting diode (μLED) as a load. The spiral antenna with its rectifying circuit is designed considering operation in the industrial, scientific, and medical (ISM) band of 2.4 GHz. The spiral coil with an inner diameter of 10 mm, an outer diameter of 12 mm, and a wire width of 0.2 mm is fabricated on a donut‐shaped flexible polyimide substrate. For biocompatibility purposes, polyimide is used as the contact lens substrate and polydimethylsiloxane (PDMS) is used for encapsulation. A 3D‐printed eye model is developed for accurately shaping the curvature of the PDMS‐encapsulated contact lens. The reflection coefficient (S11) of the fabricated antenna is tested in different conditions and on an eye model to mimic the liquid condition of the human eye. In a wide range of conditions, a minimum of −20 dB reflection coefficient (S11) is obtained.
Development of the human heart
Authors: Buijtendijk Marieke F.J. , Barnett Phil , van den Hoff Maurice J.B.
Published: February 2020

In 2014, an extensive review discussing the major steps of cardiac development focusing on growth, formation of primary and chamber myocardium and the development of the cardiac electrical system, was published. Molecular genetic lineage analyses have since furthered our insight in the developmental origin of the various component parts of the heart, which currently can be unambiguously identified by their unique molecular phenotype. Moreover, genetic, molecular and cell biological analyses have driven insights into the mechanisms underlying the development of the different cardiac components. Here, we build on our previous review and provide an insight into the molecular mechanistic revelations that have forwarded the field of cardiac development. Despite the enormous advances in our knowledge over the last decade, the development of congenital cardiac malformations remains poorly understood. The challenge for the next decade will be to evaluate the different developmental processes using newly developed molecular genetic techniques to further unveil the gene regulatory networks operational during normal and abnormal cardiac development.
Friedel−Crafts‐Type Allylation of Phenol Derivatives Catalyzed by In Situ‐Generated Silyl Cyanometallates
Authors: Yurino Taiga , Ece Hamdiye , Ohkuma Takeshi
Published: February 2020

We successfully demonstrated that Friedel−Crafts‐type allylation of phenol derivatives and allylic phosphates is catalyzed by the AgTFA/trimethylsilyl cyanide (Me3SiCN) and Pd(OAc)2/Me3SiCN combined systems to afford the C‐allylated product in a highly regioselective manner. The corresponding silyl cyanometallates generated in situ are proposed to be the active catalytic species. Lewis acidity of the reversibly formed ion pairs is appropriately regulated for this reaction. The para‐allylated anisole and phenol derivatives are selectively obtained. The para‐substituted ones are converted to the ortho‐allylated products. The reactivity of the catalytic systems is strongly dependent on the electronic nature of both electrophile and nucleophile. Substitution of an aromatic ring on the allylic phosphate is essential for the reaction. Thus, the competitive reaction of a 1 : 1 mixture of cinnamyl and simple allyl phosphates affords only the cinnamyl‐substituted product.
Non‐Enzymatic Hybrid Catalysis for Stereoconversion of l‐Amino Acid Derivatives to d‐Isomers
Authors: Nagato Yuya , Kiyokawa Mari , Ueki Yusuke , Kikuchi Jun , Ohmatsu Kohsuke , Terada Masahiro , Ooi Takashi
Published: February 2020

A catalytic transformation of N‐unprotected l‐amino esters to N‐protected d‐amino esters was developed. The combined use of a heteroaromatic aldehyde, Lewis acid, palladium complex, and chiral Brønsted acid was a key factor for the successful operation of this catalytic system. The synergistic cooperation of an appropriate aldehyde and Lewis acid was crucial for promoting an efficient racemization of l‐amino esters, while the combination of a palladium complex and chiral phosphoric acid enabled dynamic kinetic resolution through asymmetric N‐allylation, providing N‐protected d‐amino esters in good yields with up to 97 : 3 er. Following appropriate deprotection processes, d‐amino acids were obtained without loss of enantiomeric purity.
Effect of carbon black silanization on isothermal curing kinetics of epoxy nanocomposites
Authors: Soltani Seyed , Razinobakht Seyed A. , Asmatulu Ramazan
Published: February 2020

The present study was carried out to determine the effect of carbon black (CB) nanofiller silanization and loading on isothermal curing kinetics of epoxy nanocomposites. The epoxy resin specimens incorporated with 2, 4, and 8 wt% pristine CB and silanized CB were cured at isothermal temperatures of 43, 60, and 104°C. Differential scanning calorimetry was used to characterize the curing kinetics, Fourier transform infrared spectroscopy was employed to confirm silanization of CB nanofillers, and scanning electron microscopy was utilized to study the morphology of nanocomposite specimens. It was also observed that the silanization did not change the curing kinetics of CB nanocomposites significantly as compared to the neat epoxy resin. However, the curing reactions of the pristine CB nanocomposites were slower than the neat epoxy resin marked by an average 10 and 4% decrease in the final degree of cure for the nanocomposite specimens cured at 43 and 60°C, respectively. The morphological studies revealed that the silanized CB particles exhibited a more stable and homogeneous dispersion in the epoxy resin than the pristine CB particles. Potential applications for the fabricated nanocomposites include sensors, actuators, and conductive coatings for electrostatic dissipation control in plastic parts.
Kiribati economic survey: Oceans of opportunity
Authors: Webb James
Published: February 2020

Kiribati is one of the poorest and most remote Pacific nations but has the largest productive tuna fishery. The Vessel Day Scheme implemented in 2012 led to unprecedented growth in fishing revenue between 2012 and 2015, with similarly unprecedented expansion of government expenditure from 2016 to 2019. For the first time in its history, the Kiribati Government, rather than any foreign development partner, is the single largest financier of public investment. Whereas the general economy and government finances have benefited greatly from the fisheries boom, questions have been raised around recent government spending and how long there will be the fiscal space to support such discretionary decisions in the context of rapidly increasing operating costs. Fishing revenue alone will not be enough to fundamentally shift the development trajectory of the Kiribati people. A new period of reform is needed.
Sustainable reverse supply chains and circular economy in multichannel retail returns
Authors: Frei Regina , Jack Lisa , Krzyzaniak Sally‐Ann
Published: February 2020

The percentage of products being returned in multichannel retail are high and further increasing, yet many retailers and manufacturers are unaware of the importance and scale of this issue. They consider dealing with returns as a cost of doing business and are oblivious of the potential for conflicts between their corporate social responsibility commitments and their returns practices. This article investigates how far sustainable practices and circular economy concepts have been implemented in retail returns systems; it identifies vulnerabilities, barriers, and challenges to the implementation of sustainable, circular practices and suggests ways to overcome them, as sustainability, loss prevention, and profit optimisation can go hand in hand with the right approach to the organisation of the reverse supply chain. Implications of this research on strategic management are outlined. The research was conducted using in‐depth interviews and observations with four major retailers in the United Kingdom, 17 structured interviews, 100 retailer website reviews, and three retail community workshops, all with British and other European retailers.
Borderline personality disorder level predicts change in depressiveness after short‐term group psychotherapy: A study in a daily psychiatric clinic
Authors: Zajenkowska Anna , Barycka Justyna , Chotkowska Katarzyna
Published: February 2020

The project examined the comorbidity between depression symptoms and the level of borderline personality organisation among patients admitted for group psychotherapy (Study 1). It also aimed to analyse how the level of borderline personality organisation relates to the reduction in depression symptoms after short‐term psychotherapy (Study 2). The study was conducted in a day clinic where patients were receiving psychotherapy for emotional problems affecting their functioning (N = 57). The study used the Borderline Personality Inventory (BPI) and the Patient Health Questionnaire. The analysis showed that BPI was positively related to depression symptoms. The higher borderline personality organisation patients presented when entering group psychotherapy, the greater was the decrease in depression symptoms after 3 months of psychotherapy. We discuss the results in relation to the notion that the presence of depression could be a positive prognostic indicator for patients with borderline personality.
Synthesis of Ru‐Doped VN by a Soft‐Urea Pathway as an Efficient Catalyst for Hydrogen Evolution
Authors: Wang Wenquan , Shao Yalong , Wang Zhikai , Yang Zijing , Zhen Zhen , Zhang Zhonghua , Mao Changming , Guo Xiaosong , Li Guicun
Published: February 2020

Unraveling the effect of metal doping on the intrinsic activity of metal nitride remains a grand challenge. Herein, Ru (Rh)‐doped vanadium nitride are successfully synthesized via a simple soft‐urea pathway. In comparison, the Ru‐doped VN electrocatalyst exhibits much better HER performance than Rh‐doped VN electrocatalysts. The optimal Ru‐VN catalyst delivers a low overpotential of 134 (144) mV at current density of 10 mA cm−2, and a low Tafel slope of 35 (73) mV dec−1 in acidic (alkaline) condition. Such excellent performance can be attributed to the unique synergetic effect between Ru and VN. Moreover, moderate Ru dopant can effectively promote the HER kinetics of VN, resulting in mechanism transformation of hydrogen evolution from Volmer‐Heyrovsky to Volmer‐Tafel route, especially in acidic condition. This simple and facile strategy can be utilized to fabricate a series of Ru‐doped nitrides, which can be applied in energy conversion fields.
Centrifugal Pumps as Extractors
Authors: Schmitt Philipp , Hlawitschka Mark W. , Bart Hans‐Jörg
Published: February 2020

The generation of dispersions with defined droplet size distributions is important for liquid‐liquid extraction. In this respect, the capability of a centrifugal pump to generate dispersions was investigated for different operating points. For the analysis of the mixing process, a centrifugal pump was designed translucent. High‐speed images reveal the mechanism of particle breakup. Optical measurement technology and image processing with neural networks were used to determine droplet size distributions. The influence of flow rate, rotational frequency and holdup are discussed for a paraffin oil‐water system.
Rh‐Catalyzed Reaction of Propargylic Alcohols with Aryl Boronic Acids–Switch from β‐OH Elimination to Protodemetalation
Authors: Wang Weiyi , Qian Hui , Ma Shengming
Published: February 2020

Summary of main observation and conclusion

It is known that Rh‐catalyzed reaction of propargylic alcohols with aryl metallic reagents undergoes SN2’‐type reaction affording allenes via a sequential arylmetalation and β‐OH elimination process. Here we report a Rh/Ag‐cocatalyzed reaction of propargylic alcohols with organoboronic acids affording stereo‐defined (E)‐3‐arylallylic alcohols via arylmetalation and protodemetalation with a high regio‐ and stereoselectivity under very mild conditions. The reaction exhibits a good substrate scope and the compatibility with synthetically useful functional groups with no racemization for optically active propargylic alcohols. Such a reaction may also be extended to homopropargylic alcohols with a remarkable regioselectivity and exclusive E‐stereoselectivity.
The entropic measure transform
Authors: Wang Renjie , Hyndman Cody , Kratsios Anastasis
Published: February 2020

We introduce the entropic measure transform (EMT) problem for a general process and prove the existence of a unique optimal measure characterizing the solution. The density process of the optimal measure is characterized using a semimartingale BSDE under general conditions. The EMT is used to reinterpret the conditional entropic risk‐measure and to obtain a convenient formula for the conditional expectation of a process that admits an affine representation under a related measure. The EMT is then used to provide a new characterization of defaultable bond prices, forward prices and futures prices when a jump‐diffusion drives the asset. The characterization of these pricing problems in terms of the EMT provides economic interpretations as maximizing the returns subject to a penalty for removing financial risk as expressed through the aggregate relative entropy. The EMT is shown to extend the optimal stochastic control characterization of default‐free bond prices of Gombani & Runggaldier (2013). These methods are illustrated numerically with an example in the defaultable bond setting. The Canadian Journal of Statistics 48: 97–129; 2020 © 2020 Statistical Society of Canada
State of palliative care services at US cancer centers: An updated national survey
Authors: Hui David , De La Rosa Allison , Chen Joseph , Dibaj Seyedeh , Delgado Guay Marvin , Heung Yvonne , Liu Diane , Bruera Eduardo
Published: February 2020

Background

This study examined the changes in outpatient palliative care services at US cancer centers over the past decade.

Methods

Between April and August 2018, all National Cancer Institute (NCI)–designated cancer centers and a random sample of 1252 non–NCI‐designated cancer centers were surveyed. Two surveys used previously in a 2009 national study were sent to each institution: a 22‐question cancer center executive survey regarding palliative care infrastructure and attitudes toward palliative care and an 82‐question palliative care program leader survey regarding detailed palliative care structures and processes. Survey findings from 2018 were compared with 2009 data from 101 cancer center executives and 96 palliative care program leaders.

Results

The overall response rate was 69% (140 of 203) for the cancer center executive survey and 75% (123 of 164) for the palliative care program leader survey. Among NCI‐designated cancer centers, a significant increase in outpatient palliative care clinics was observed between 2009 and 2018 (59% vs 95%; odds ratio, 12.3; 95% confidence interval, 3.2‐48.2; P < .001) with no significant changes in inpatient consultation teams (92% vs 90%; P = .71), palliative care units (PCUs; 26% vs 40%; P = .17), or institution‐operated hospices (31% vs 18%; P = .14). Among non–NCI‐designated cancer centers, there was no significant increase in outpatient palliative care clinics (22% vs 40%; P = .07), inpatient consultation teams (56% vs 68%; P = .27), PCUs (20% vs 18%; P = .76), or institution‐operated hospices (42% vs 23%; P = .05). The median interval from outpatient palliative care referral to death increased significantly, particularly for NCI‐designated cancer centers (90 vs 180 days; P = 0.01).

Conclusions

Despite significant growth in outpatient palliative care clinics, there remain opportunities for improvement in the structures and processes of palliative care programs.
Lignin deposits in pedicel xylem vessels regulate water transport during seed maturation in soybean
Authors: Itoyama Haruka , Nakagawa Andressa C.S. , Ariyoshi Yuri , Ario Nobuyuki , Yuasa Takashi , Iwaya‐Inoue Mari , Ishibashi Yushi
Published: February 2020

Seed desiccation during maturation is important for seed post‐maturation behavior and harvest. However, the desiccation mechanism in soybean [Glycine max (L.) Merr.] seed maturation is hardly known. In this study, we found that water content in seeds, pods, and pedicels decreased faster than that in peduncles and stems. Therefore, we focused on the role of the pedicel during seed maturation. Morphological analysis revealed deposits in xylem vessels in the pedicel at 61 d after flowering (DAF), but no deposits in the peduncle. Microarray analysis showed that lignin biosynthesis‐related genes were expressed in the pedicel at 61 DAF. Among them, the expression of GmPAL, Gm4CL, GmC3H, and GmCAD increased in the pedicel during seed maturation. Pedicel lignin content also increased by 61 DAF; lignin accumulated in xylem vessels. These results suggest that lignin deposits in pedicel xylem vessels cause soybean seed desiccation during maturation.
Labels to prevent the detrimental effects of media on body image: A systematic review and meta‐analysis
Authors: Danthinne Elisa S. , Giorgianni Francesca E. , Rodgers Rachel F.
Published: February 2020

Objective

Most advertisements contain thin‐ideal imagery enhanced by digital modification. The deleterious effects on body image and eating disorder risk of exposure to such images have been well documented. One of the proposed macro‐level solutions to mitigate these effects has been the use of labels on images, primarily disclaimer labels. A growing number of studies have explored the usefulness of such labels in protecting body image against the detrimental effects of media exposure; however, findings have been divergent.

Methods

The current study aimed to conduct a systematic review and meta‐analysis of the existing literature investigating the effects of including labels on media images on body image.

Results

The systematic review identified n = 22 studies that were included in a narrative review, n = 18 were included in the meta‐analysis. Overall, findings provided little support for the use of disclaimer or warning labels as a means of protecting against the detrimental effects of media exposure on body image. Furthermore, findings suggested that such labels might increase state appearance comparison when exposed to media images.

Discussion

These findings are especially concerning in light of recent legislative efforts to mitigate media effects through the use of labels on imagery, as well as industry initiatives based on image labeling. Additional research examining alternative strategies for universal prevention of body image and eating concerns is warranted.
Assessment of fracture risk in women with eating disorders: The utility of dual‐energy x‐ray absorptiometry (DXA)—Clinical cohort study
Authors: Frølich Jacob , Winkler Laura Al‐Dakhiel , Abrahamsen Bo , Bilenberg Niels , Hermann Anne P. , Støving René K.
Published: February 2020

Objective

Eating disorders (EDs) are associated with decreased bone mineral density (BMD) and increased fracture risk. The association between BMD and fracture risk in EDs is not well elucidated. We aimed to assess BMD in an ED cohort of patients with active disease and patients in remission, and to assess the predictive value of BMD on incidence of fractures.

Method

We included 344 female patients (median age 19, IQR 16; 24) referred to ED treatment. Later, patients were invited to follow‐up including assessment of remission status and a dual‐energy x‐ray absorptiometry (DXA)‐scan. Information on fractures was obtained through the Danish National Registry of Patients.

Results

Patients with current anorexia nervosa (AN) had significantly lower BMD compared to controls at lumbar spine (16% lower, p < .0001), femoral neck (18% lower, p < .0001), and total hip (23% lower, p < .0001). Recovered AN patients had higher BMD compared to those with current disease (p < .0001 for all measures), but lower BMD compared to controls at lumbar spine (p < .01) and hip (p < .001). BMD did not differ between BN patients and controls. In patients with active eating disorders not otherwise specified, BMD was lower only at the total hip (p < .005). We found no association between BMD and fracture risk.

Conclusion

We confirm that AN is associated with low BMD, whereas BN is not. Remission is associated with higher BMD compared to patients with active AN, but a deficit remains. We found no significant association between BMD and fracture risk, challenging the benefit of the widespread use of DXA scans in young women with ED.

Clinical trial registration

The study is registered in ClinicalTrials.gov, number NCT00267228.
Elevated precipitation alters the community structure of spring ephemerals by changing dominant species density in Central Asia
Authors: Jia Yangyang , Sun Yu , Zhang Tao , Shi Zhaoyong , Maimaitiaili Baidengsha , Tian Changyan , Feng Gu
Published: February 2020

Global climate change is one of the most pressing conservation challenges; in particular, changes in precipitation regimes have already substantially influenced terrestrial ecosystems. However, the mechanisms influencing precipitation changes on individual plants and the plant communities in desert grasslands have yet to be fully elucidated. We therefore examine the influence of increased precipitation on plant community compositions in the Gurbantunggut Desert, Xinjiang, northwestern China, from 2005 to 2009. We found that growth of all plant species and the community productivities increased markedly with enhanced water input. Cover of ephemeral synusia also significantly increased due to increased precipitation, implying that the role of the ephemeral community for stabilization of sand dunes was strengthened by increased precipitation. The response of plant community compositions to increased precipitation was primarily reflected as changes in plant density, while increased precipitation did not affect plant species richness and the diversity index. Dominant species drove the response of plant density to increasing precipitation during the five‐year study period. However, the relative responses of rare species were stronger than those of the dominant species, thereby potentially driving species turnover with long‐term increased precipitation. This finding improved our understanding of how increased precipitation drives the changes in plant community composition in desert grasslands and will help to better predict changes in the community composition of ephemerals under future global climate change scenarios.
Neuroendocrine effects of naltrexone versus nalmefene in humans
Authors: Butelman Eduardo R. , Fry Rebecca S. , Kimani Rachel , Reed Brian , Kreek Mary Jeanne
Published: February 2020

Objective

Naltrexone and nalmefene are approved for the treatment of alcohol use disorders, in different countries. Naltrexone is also approved for the treatment for opioid use disorders, most recently in a depot formulation. These compounds target primarily μ(mu)‐ and κ(kappa)‐opioid receptor systems, which are involved in the downstream neurobiological effects of alcohol and in the modulation of neuroendocrine stress systems. The study objective was to compare the neuroendocrine effects of naltrexone and nalmefene on adrenocorticotropic hormone (ACTH), cortisol, and prolactin, in normal volunteers.

Method

Adult normal volunteers (n = 11 male and n = 9 female) were studied in a stress‐minimized inpatient setting on three consecutive days, after intravenous saline, naltrexone HCl (10 mg), or nalmefene HCl (10 mg), in fixed order. ACTH, cortisol, and prolactin were analyzed pre‐injection and up to 180 min post‐injection.

Results

Naltrexone and nalmefene caused elevations in ACTH and cortisol compared with saline. Nalmefene had a greater effect on ACTH and cortisol, compared with naltrexone. Both compounds also caused elevations in prolactin in males (females were not examined, due to the influence of menstrual cycle on prolactin).

Conclusions

This study suggests that both nalmefene and naltrexone have effects potentially due to κ‐partial agonism in humans, as well as antagonist effects at μ‐receptors.
Variable effects of forest canopies on snow processes in a valley of the central Spanish Pyrenees
Authors: Sanmiguel‐Vallelado Alba , López‐Moreno Juan I. , Morán‐Tejeda Enrique , Alonso‐González Esteban , Navarro‐Serrano Francisco M. , Rico Ibai , Camarero J. Julio
Published: February 2020

Snowpacks and forests have complex interactions throughout the large range of altitudes where they co‐occur. However, there are no reliable data on the spatial and temporal interactions of forests with snowpacks, such as those that occur in nearby areas that have different environmental conditions and those that occur during different snow seasons. This study monitored the interactions of forests with snowpacks in four forest stands in a single valley of the central Spanish Pyrenees during three consecutive snow seasons (2015/2016, 2016/2017 and 2017/2018). Daily snow depth data from time‐lapse cameras were compared with snow data from field surveys that were performed every 10–15 days. These data thus provided information on the spatial and temporal changes of snow–water equivalent (SWE). The results indicated that forest had the same general effects on snowpack in each forest stand and during each snow season. On average, forest cover reduced the duration of snowpack by 17 days, reduced the cumulative SWE of the snowpack by about 60% and increased the spatial heterogeneity of snowpack by 190%. Overall, forest cover reduced SWE total accumulation by 40% and the rate of SWE accumulation by 25%. The forest‐mediated reduction of the accumulation rate, in combination with the occasional forest‐mediated enhancement of melting rate, explained the reduced duration of snowpacks beneath forest canopies. However, the magnitude and timing of certain forest effects on snowpack had significant spatial and temporal variations. This variability must be considered when selecting the location of an experimental site in a mountainous area, because the study site should be representative of surrounding areas. The same considerations apply when selecting a time period for study.
A novel security algorithm ECC‐L for wireless sensor network
Authors: Ajaykumar Notom , Sarvagya Mrinal , Parandkar Parag
Published: February 2020

Wireless communication has poised to become one of the most predominant area of research in the field of communication engineering. Wireless Sensor Network also plays a significant role in shaping and linking IoT and communication era. The proposed work considers the two most influential parameters, the power consumption and security, for accessing the performance of Wireless Sensor Network. A novel security algorithm Rabin based Elliptic Curve Cryptosystem ‐ Linear (ECC‐L) has been designed, implemented and compared with existing ECC algorithm. The proposed algorithm uses double binding hash code technique. It supports sensor nodes with bio hash code for identification of authorization network to share the data. The impact of increase in number of nodes to the key performance metrics of WSN like, energy, packet loss, delay, throughput etc., is measured on ECC and proposed ECC‐L by performing simulations. Qualitatively, the metrics show peak performance and significant performance improvement compared to ECC algorithm in terms of reduction in the packet loss, obtaining maximum throughput, avoidance of retransmissions and enhancement of energy efficiency in wireless sensor network. Quantitatively, the simulation results show that the proposed Rabin ECC‐L algorithm perform enhanced better than the existing ECC algorithm for the impact of increase in number of nodes on reduction of control overheads by 21%, reduction in energy consumption by 27%, decrease in packet losses by 13%, increase in throughput by 32% and decrease in average delay by 32%.
Evaluation of pharmacy students' perceptions of clinical pharmacy in South Africa
Authors: Ilcewicz Haley N. , Coetzee Renier , Taylor Mary , Piechowski Kara , Martello Jay L. , Wietholter Jon P.
Published: February 2020

Introduction

The University of the Western Cape (UWC) is integrating clinical, hospital‐based experiential learning into the final year of its pharmacy education. As clinical pharmacy continues to expand in South Africa, students' perceptions of the evolving field are not yet described in the literature.

Objectives

The purpose of this study was to describe UWC's pharmacy students' perceptions of clinical pharmacy practice as it continues to develop in South Africa.

Methods

This study was a cross‐sectional, observational study of second, third, and fourth year pharmacy students at UWC. The 18‐item questionnaire was distributed via an online survey tool to participants during the second semester of the 2018 academic year.

Results

One‐hundred forty nine (52%) students completed the survey. Ninety‐four percent of students had previous experience in a pharmacy setting but only 28.2% had experience observing a clinical pharmacist. UWC students felt that practicing clinical pharmacy is valuable (median 5 ± 0) and did not think it takes too much time and effort (median 2 ± 1), but also believed that there are barriers to its practice (median 4 ± 1). Overall, they did not think they had adequate training in clinical pharmacy (median 3 ± 2) and agreed that further training is required in order to practice clinical pharmacy (median 5 ± 1).

Conclusion

Pharmacy students at UWC had an overall positive outlook on the practice of clinical pharmacy. Students at UWC School of Pharmacy are exposed to an innovative clinical experiential program that may have influenced their perceptions of clinical pharmacy, but still feel further clinical training beyond their curricula is required to adequately practice clinical pharmacy. Future research should focus on other pharmacy students' and pharmacists' perceived barriers to practicing clinical pharmacy as the field continues to evolve in South Africa.
Unique spectral signature of human cutaneous squamous cell carcinoma by photoacoustic imaging
Authors: Hult Jenny , Dahlstrand Ulf , Merdasa Aboma , Wickerström Karin , Chakari Rehan , Persson Bertil , Cinthio Magnus , Erlöv Tobias , Albinsson John , Gesslein Bodil , Sheikh Rafi , Malmsjö Malin
Published: February 2020

Cutaneous squamous cell carcinoma (cSCC) is a common skin cancer with metastatic potential. To reduce reoperations due to nonradical excision, there is a need to develop a technique for identification of tumor margins preoperatively. Photoacoustic (PA) imaging is a novel imaging technology that combines the strengths of laser optics and ultrasound. Our aim was to determine the spectral signature of cSCC using PA imaging and to use this signature to visualize tumor architecture and borders. Two‐dimensional PA images of 33 cSCCs and surrounding healthy skin were acquired ex vivo, using 59 excitation wavelengths from 680 to 970 nm. The spectral response of the cSCCs was compared to healthy tissue, and the difference was found to be greatest at wavelengths in the range 765 to 960 nm (P < .05). Three‐dimensional PA images were constructed from spectra obtained in the y‐z plane using a linear stepper motor moving along the x‐plane. Spectral unmixing was then performed which provided a clear three‐dimensional view of the distribution of tumor masses and their borders.