bluuebunny/crossref_metadata_2025 huggingface dataset:
Population structure, genetic diversity, and colonization history of the eastern pondmussel, Sagittunio nasutus, in the Great Lakes drainage
Authors: Scott Mariah W. , Morris Todd J. , Zanatta David T.
Published: February 2020

The eastern pondmussel, Sagittunio nasutus (Bivalvia: Unionida), has declined in abundance and distribution in eastern North America over the last few decades. The declines are predominantly the result of infestation by invasive dreissenid mussels and changes in habitat. The species is now considered imperilled across large portions of its distribution, especially in the Laurentian Great Lakes region.

The genetic diversity and structure of the remnant populations in the Great Lakes region were assessed using 10 newly developed microsatellite DNA loci for S. nasutus. Understanding the remaining populations can inform future management projects and determine whether the remnant populations have experienced a genetic bottleneck or a founder effect. We hope that this will inform the conservation of other species in regions founded by, and isolated from, a more genetically diverse source population or with disjointed geographical distributions.

Focusing on the Great Lakes region, samples (n = 428) from 62 collection sites in 28 water bodies were collected. Across the locations sampled for S. nasutus 11 genetic populations were identified, with significant genetic differentiation among them. The genetic structure of the species was assessed, with genetic similarities among populations compared and with geographical routes of colonization and gene flow evaluated.

Initial colonization from the Atlantic coast into Lake Erie and Lake Ontario is evident, followed by colonization events into nearby inland rivers and lakes. Analyses found evidence of inbreeding in all but one population and evidence of past genetic bottlenecks or strong founder effects in all but four populations. This study deepens our understanding of the genetic past and present of this imperilled species, providing conservation suggestions for the future management of the species.
Cultural practices of the Zulu ethnic group on the body and their influence on body donation
Authors: De Gama Brenda Z. , Jones David Gareth , Bhengu Thamsanqa T. , Satyapal Kapil S.
Published: February 2020

Cultural practices in the African continent have been thought to impact negatively on body donation. Thus, most African countries continue to rely on unclaimed bodies for dissection programs, or bequests from the white population. The latter situation is dominant in South African medical schools. Since South Africa is multi‐cultural with nine main ethnic groups of the Black African population, it is important to seek the reasons behind lack of participation in body donation. This report represents a move in this direction with its qualitative study of the cultural practices of the Zulu ethnic group in the province of KwaZulu‐Natal from the perspective of a variety of participants, with emphasis on their treatment of the human body after death. Four themes emerged from interviews: (1) Death is not the end; (2) Effect of belief in ancestors; (3) Significance of rituals and customs carried out on human tissue; and (4) Burial as the only method of body disposal. Each of these themes is discussed in relation to the likelihood of body donation being seen by Zulus as an acceptable practice. It is concluded that this is unlikely, on account of the need to preserve the linkage between the physical human body and the spirit of the deceased person, and the perceived ongoing relationship between the spirit of the dead and the living. In view of these conclusions, a number of options are canvassed about the manner in which anatomists in KwaZulu‐Natal might obtain bodies for dissection. These possibilities have implications for anatomists working in comparable cultural contexts.
The Link between Autotomy and CNS Regeneration: Echinoderms as Non‐Model Species for Regenerative Biology
Authors: Byrne Maria
Published: February 2020

Achieving regeneration of the central nervous system (CNS) is a major challenge for regenerative medicine. The inability of mammals to regrow a severed CNS contrasts with the amazing regenerative powers of their deuterostome kin, the echinoderms. Rapid CNS regeneration from a specialized autotomy plane in echinoderms presents a highly tractable and suitable non‐model system for regenerative biology and evolution. Starfish arm autotomy triggers mass cell migration and local proliferation, facilitating rapid CNS regeneration. Many regeneration events in nature are preceded by autotomy and there are striking parallels between autotomy and regeneration in starfish and lizards. Comparison of these systems holds promise to provide insight into regeneration deficiency in higher vertebrates and to uncover evolutionarily conserved deuterostome‐chordate regenerative processes. This will help identify mechanisms that may be present but inactive in higher vertebrates to address the problem of their poor regenerative capacities and the challenge to achieve CNS repair and regrowth.
Multiply imputing missing values arising by design in transplant survival data
Authors: Pankhurst Laura , Mitra Robin , Kimber Alan , Collett Dave
Published: February 2020

In this article, we address a missing data problem that occurs in transplant survival studies. Recipients of organ transplants are followed up from transplantation and their survival times recorded, together with various explanatory variables. Due to differences in data collection procedures in different centers or over time, a particular explanatory variable (or set of variables) may only be recorded for certain recipients, which results in this variable being missing for a substantial number of records in the data. The variable may also turn out to be an important predictor of survival and so it is important to handle this missing‐by‐design problem appropriately. Consensus in the literature is to handle this problem with complete case analysis, as the missing data are assumed to arise under an appropriate missing at random mechanism that gives consistent estimates here. Specifically, the missing values can reasonably be assumed not to be related to the survival time. In this article, we investigate the potential for multiple imputation to handle this problem in a relevant study on survival after kidney transplantation, and show that it comprehensively outperforms complete case analysis on a range of measures. This is a particularly important finding in the medical context as imputing large amounts of missing data is often viewed with scepticism.
Anti‐invasive effect and pharmacological mechanism of genistein against colorectal cancer
Authors: Chen Xiaoyu , Wu Youjun , Gu Junzhao , Liang Ping , Shen Meizhen , Xi Jiaxi , Qin Jian
Published: February 2020

Colorectal cancer (CRC) refers to a deadly carcinoma following potent invasiveness and metastasis in advanced stage. Unfortunately, existing anti‐CRC medicine is insufficient for chemotherapy in addition to adverse effects. Consequently, the candidate natural ingredient for treating CRC needs to be further developed. Our previous experiments report that genistein exerts beneficial effects to inhibit CRC cells via an antiproliferative mechanism. Based on the metastatic characteristics of staging CRC, anti‐invasive and antimetastatic pharmacological activities using genistein remain uninvestigated. The scientific purpose of this study was to disclose the antimetastatic mechanism by using human and cell culture/nude mice samples, followed by biochemical tests and immunoassays. In human study, these CRC cases resulted in increased transforming growth factor beta‐1 (TGF‐β1) levels, long noncoding RNA (lncRNA) TTTY18 expressions, followed with up‐regulated Ki‐67, serum and glucocorticoid regulated kinase 1 (SGK1), AktSer473 expressions. In a study in vitro, genistein‐dosed CRC cells showed suppressed cell viability, promoted cell apoptosis, reduced Ki‐67 positive cells, reduced cellular migration, down‐regulated expressions of TTTY18, SGK1, AktSer473, p38 MAPKTyr323. In a further study in vivo, genistein‐dosed tumor‐bearing nude mice exhibited visibly reduced body mass, lowered tumorous TGF‐β1 and TTTY18 contents. In addition, intracellular numbers of SGK1, AktSer473, p38 MAPKTyr323 positive cells were reduced dose‐dependently. Collectively, these human and experimentative findings reveal that genistein pharmacologically exerts the potential antimetastatic CRC effects, possibly through a molecular mechanism of inhibiting TTTY18/Akt pathway in CRC cells.
Mammalian Pericardium‐Based Bioprosthetic Materials in Xenotransplantation and Tissue Engineering
Authors: Grebenik Ekaterina A. , Gafarova Elvira R. , Istranov Leonid P. , Istranova Elena V. , Ma Xiaowei , Xu Jing , Guo Weisheng , Atala Anthony , Timashev Peter S.
Published: February 2020

Bioprosthetic materials based on mammalian pericardium tissue are the gold standard in reconstructive surgery. Their application range covers repair of rectovaginal septum defects, abdominoplastics, urethroplasty, duraplastics, maxillofacial, ophthalmic, thoracic and cardiovascular reconstruction, etc. However, a number of factors contribute to the success of their integration into the host tissue including structural organization, mechanical strength, biocompatibility, immunogenicity, surface chemistry, and biodegradability. In order to improve the material's properties, various strategies are developed, such as decellularization, crosslinking, and detoxification. In this review, the existing issues and long‐term achievements in the development of bioprosthetic materials based on the mammalian pericardium tissue, aimed at a wide‐spectrum application in reconstructive surgery are analyzed. The basic technical approaches to preparation of biocompatible forms providing continuous functioning, optimization of biomechanical and functional properties, and clinical applicability are described.
Advanced X‐ray Absorption Spectroscopy Analysis to Determine Structure‐Activity Relationships for Cu‐Zeolites in the Direct Conversion of Methane to Methanol
Authors: Kvande Karoline , Pappas Dimitrios K. , Borfecchia Elisa , Lomachenko Kirill A.
Published: February 2020

An industrial process for direct conversion of methane to methanol (DMTM) would revolutionize methane as feedstock for the chemical industry and it would be a cherished contribution to climate change mitigation. At the present stage, it is a rather remote perspective, but the search for the materials that would make it possible and economically viable, is very active. Cu‐exchanged zeolites have been shown to cleave the C−H bond of methane at low temperatures (≤200 °C), and has been extensively studied for the stepwise DMTM conversion over the last decades. The determination of the speciation of CuxOy‐species in zeolites and the understanding of their role in the reaction mechanism has been heavily debated. Lately, advanced X‐ray absorption spectroscopy (XAS) analysis has been standing out as a powerful technique for investigating the behavior of Cu in zeolites. In this review we focus on thein situandoperandostudies of changes in the electronic and structural properties of Cu, during the different steps of the DMTM conversion uncovered by XAS, which have led to new and insightful information about the complex behavior of Cu‐zeolites in the DMTM process.
Unsymmetrical Strategy Makes Significant Differences in α‐Diimine Nickel and Palladium Catalyzed Ethylene (Co)Polymerizations
Authors: Hu Xiaoqiang , Zhang Yuxing , Zhang Yixin , Jian Zhongbao
Published: February 2020

Ligand steric bulk is one of the most important parameters on determining activity, polymer molecular weight, and branching density in α‐diimine Ni(II) and Pd(II) catalyzed ethylene polymerization. In this contribution, we delineated an unsymmetrical strategy to shed light on the effect of steric bulk in α‐diimine species via the unsymmetrically pentiptycenyl/dibenzhydryl α‐diimine Ni(II) and Pd(II) catalysts Ipty/Ph‐Ni and Ipty/Ph‐Pd versus symmetrical pentiptycenyl analogues Ipty‐Ni and Ipty‐Pd and symmetrical dibenzhydryl analogues Ph‐Ni and Ph‐Pd. In the Ni(II) catalyzed ethylene polymerization, new features have been revealed: (1) with the increase of steric bulk (Ph‐Ni > Ipty/Ph‐Ni > Ipty‐Ni), in a relatively long 30 min polymer molecular weights increase, yet Ipty/Ph‐Ni produces the highest molecular weight (1230 kDa) in a short 5 min; (2) with increasing steric bulk, branching density first rises and then falls, liking a downward parabola. In the Pd(II) catalyzed ethylene polymerization, increasing steric bulk enhanced activity and molecular weight or not, dependent on temperature, but usually decreased branching density. Consequently, Ipty/Ph‐Pd gave the highest activity and the highest molecular weight (412 kDa) at challenging high temperature of 70 °C. Plausible insights have been given to address these differences from previous results. Notably, unsymmetrical Ni(II) and Pd(II) catalysts also enabled copolymerizations of ethylene with various polar comonomers.
Synthesis of 3D IrRuMn Sphere as a Superior Oxygen Evolution Electrocatalyst in Acidic Environment
Authors: Aizaz Ud Din Muhammad , Irfan Syed , Dar Sami Ullah , Rizwan Syed
Published: February 2020

The design of a three‐dimensional structure for an Ir‐based catalyst offers a great opportunity to improve the electrocatalytic performance and maximize the use of the precious metal. Herein, a novel wet chemical strategy is reported for the synthesis of an IrRuMn catalyst with a sphere structure and porous features. In the synthetic process, the combined use of citric acid and formamide is requisite for the formation of the sphere structure. This method leads to a favorable 3D IrRuMn sphere structure with many fully exposed active sites. Furthermore, an alloying noble metal, such as Ir or Ru, with the transition metal leads to enhanced oxygen evolution reaction (OER) activity. The doping of a transition metal, such as Mn, is an interesting example, because it exhibits stability and activity in both acidic and alkaline media. For the OER, the IrRuMn sphere catalyst exhibits an overpotential of 260 mV at a current density of 10 mA cm−2 in strongly acidic 0.1 m HClO4, which is superior to that of a commercial IrO2/C catalyst. This approach provides a novel way to synthesize an Ir‐based multimetallic spherical electrocatalyst, which exhibits exceptional efficiency for the acidic OER. It will pave the way for new approaches to the practical utilization of PEM electrolyzers.
Hierarchical Tubular Architecture Constructed by Vertically Aligned CoS2‐MoS2 Nanosheets for Hydrogen Evolution Electrocatalysis
Authors: Cai Ze‐Xing , Na Jongbeom , Lin Jianjian , Alshehri Abdulmohsen Ali , Alzahrani Khalid Ahmed , Alghamdi Yousef Gamaan , Lim Hyunsoo , Zheng Jie , Xia Wei , Wang Zhong‐Li , Yamauchi Yusuke
Published: February 2020

Developing efficient electrocatalysts for the hydrogen evolution reaction (HER) is crucial for establishing a sustainable and environmentally friendly energy system, but it is still a challenging issue. Herein, hierarchical tubular‐structured CoS2‐MoS2/C as efficient electrocatalysts are fabricated through a unique metal–organic framework (MOF) mediated self‐sacrificial templating. Core–shell structured MoO3@ZIF‐67 nanorods are used both as a precursor and a sacrificial template to form the one‐dimensional tubular heterostructure where vertically aligned two‐dimensional CoS2‐MoS2 nanosheets are formed on the MOF‐derived carbon tube. Trace amounts of noble metals (Pd, Rh, and Ru) are successfully introduced to enhance the electrocatalytic property of the CoS2‐MoS2/C nanocomposites. The as‐synthesized hierarchical tubular heterostructures exhibit excellent HER catalytic performance owing to the merits of the hierarchical hollow architecture with abundantly exposed edges and the uniformly dispersed active sites. Impressively, the optimal Pd‐CoS2‐MoS2/C‐600 catalyst delivers a current density of 10 mA cm−2 at a low overpotential of 144 mV and a small Tafel slope of 59.9 mV/dec in 0.5 m H2SO4. Overall, this MOF‐mediated strategy can be extended to the rational design and synthesis of other hollow heterogeneous catalysts for scalable hydrogen generation.
Aqueous Synthesis of Triphenylphosphine‐Modified Gold Nanoparticles for Synergistic In Vitro and In Vivo Photothermal Chemotherapy
Authors: Benyettou Farah , Ramdas Nair Anjana , Dho Yaereen , Prakasam Thirumurugan , Pasricha Renu , Whelan Jamie , Traboulsi Hassan , Mazher Javed , Sadler Kirsten C. , Trabolsi Ali
Published: February 2020

Triphenylphosphine (TPP) surface‐functionalized and F‐108 Pluronic‐stabilized gold nanoparticles (F‐108@TPP‐AuNPs) have been synthesized through a one‐step approach, leading to well‐defined (9.6±1.6 nm) and water‐soluble nanoparticles by microwave heating an aqueous solution of TPP‐AuICl in the presence of a Pluronic polymer under basic conditions. TPP release was negligible under physiological conditions, but enhanced significantly at an acidic pH (5.4) mimicking that of a cancer cell. Laser irradiation (532 nm) raised the temperature of an aqueous solution of F‐108@TPP‐AuNPs to 51.7 °C within 5 min, confirming efficient light‐to‐heat conversion capabilities without significant photodegradation. TEM confirmed intracellular localization of F‐108@TPP‐AuNPs in the cytosol, endosomes and lysosomes of HeLa cells. F‐108@TPP‐AuNPs were well tolerated by HeLa cells and zebrafish embryos at ambient temperatures and became toxic upon heat activation, suggesting synergistic interactions between heat and cytotoxic action by TPP.
Gasification performance of torrefied Timothy hay and spruce wood chars in a CO2 environment
Authors: Parvez Ashak Mahmud , Afzal Muhammad T.
Published: February 2020

Timothy hay abundantly available in New Brunswick, Canada, is mostly used for animal feed and bedding. Upgrading biomass using Torrefaction method can offer benefits in its waste management, energy density and energy conversion efficiency. Temperature and residence time play an important role in the torrefaction process. Meanwhile, CO2 gasification is also a promising thermochemical conversion process due to its potential to reduce net GHG emissions and tune syngas composition. This study investigates the impact of torrefaction parameters on isothermal and non‐isothermal CO2 gasification of Timothy hay and spruce chars. Timothy hay chars exhibited higher CO2 gasification reactivity than chars from spruce. The physicochemical properties analysis indicated that higher reactivity of Timothy hay char was mainly attributed to the high amount of alkali and alkaline earth metal (AAEM) content, relatively large BET surface area, a high number ofactive sites, and a low crystalline index. Moreover, in both experimental cases, char derived through a high heating rate and high residence time conditions exhibited improved gasification performance, which was attributed to the generation of large amounts of AAEM (Ca and K) and high specific surface area. Co‐gasification results during non‐isothermal processes under CO2 showed the presence of larger interactions in coal char/Timothy hay char blends than that of coal char/spruce char blends. For both experimental conditions, interactions were enhanced once the char prepared from high heating rate and high residence time was gasified with coal char. Thus, the proposed approach is a sustainable way of conversion of Timothy hay under CO2 environment.
Does a higher American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI‐RADS) score forecast an increased risk of malignancy? A correlation study of ACR TI‐RADS with FNA cytology in the evaluation of thyroid nodules
Authors: Modi Lopa , Sun Wei , Shafizadeh Negin , Negron Raquel , Yee‐Chang Melissa , Zhou Fang , Simsir Aylin , Sheth Sheila , Brandler Tamar C.
Published: February 2020

Background

Ultrasound has become the initial approach to evaluating thyroid nodules, facilitating the distinction between benign and malignant nodules based on composition, echogenicity, nodule border or margin, shape, the presence of calcifications, and nodule dimensions. The American College of Radiology (ACR) recommended the Thyroid Imaging Reporting and Data System (TI‐RADS) as a classification system to standardize thyroid ultrasound reports and to predict the probability of malignancy in thyroid nodules using a scoring system (TR1‐TR5) based on multiple ultrasound characteristics and nodule size. Fine‐needle aspiration (FNA) is recommended as the next step for nodules that warrant further workup. The authors assessed the accuracy of the ACR TI‐RADS based on the corresponding FNA cytology results (Bethesda system diagnoses I‐VI).

Methods

ACR TI‐RADS ultrasound reports and corresponding FNA cytology diagnoses from January 1, 2018 to August 30, 2018 were evaluated.

Results

From January 1, 2018 to August 30, 2018, 2306 thyroid ultrasound‐guided FNAs were performed at our institution. Of 2306 cases, 361 had ACR TI‐RADS reports available. The majority of FNAs were TR4 (180; 49.9%) or TR3 (108; 29.9%). No TR2 or TR3 nodules were associated with Bethesda category V or VI diagnoses. The majority of TR4 nodules (142 of 180; 78.9%) and TR5 nodules (42 of 65; 64.6%) exhibited benign (Bethesda category II) cytology. Fourteen TR5 cases (21.5%) had malignant (Bethesda category VI) cytology.

Conclusions

Although there were no TR2 or TR3 malignant (Bethesda category VI) diagnoses, and there were only a few malignancies in the TR4 and TR5 categories, the current results reassert the notion that the ACR TI‐RADS scoring system shows at least some correlation between benign or malignant cytology diagnoses, as illustrated by the greater number of malignant cases in the higher ACR TI‐RADS categories.
A multi‐Internet service provider game: Equilibrium, stability, and characteristics
Authors: Fu Hong , Chen Bo , Zhang Bin
Published: February 2020

This paper proposes a multi‐Internet service provider (ISP) game model for investigating the economic interactions among ISPs who compete or cooperate with each other for customers. The equilibrium and stability properties of the multi‐ISP game in different market scenarios, that is, competitive market, collaborative market, mixed market, and winner‐take‐all market, are investigated. Some qualitative and managerial insights into market outcomes are obtained to characterize the set of equilibria. Furthermore, numerical examples are also employed to illustrate the typical characteristics of the multi‐ISP market. The simulation results provide possible explanations for the evolution of the multi‐ISP game. The results also indicate that the constructed model can predict the main characteristics of the Internet service market in different market scenarios.
Utilising Saturated Hydrocarbon Isosteres of para Benzene in the Design of Twist‐Bend Nematic Liquid Crystals
Authors: Al‐Janabi Adam , Mandle Richard J.
Published: February 2020

The nematic twist‐bend (NTB) liquid crystal phase possesses a local helical structure with a pitch length of a few nanometres and is the first example of spontaneous symmetry breaking in a fluid system. All known examples of the NTB phase occur in materials whose constituent mesogenic units are aromatic hydrocarbons. It is not clear if this is due to synthetic convenience or a bona fide structural requirement for a material to exhibit this phase of matter. In this work we demonstrate that materials consisting largely of saturated hydrocarbons can also give rise to this mesophase.
Communicating the stakeholder engagement process: A cross‐country analysis in the tourism sector
Authors: Iazzi Antonio , Pizzi Simone , Iaia Lea , Turco Mario
Published: February 2020

Stakeholder engagement (SE) is considered a best practice in sustainability reporting, as it increases companies' social legitimacy and reputation. Companies have to properly communicate the SE activities, paying attention to the social, cultural, and political factors that affect the perception of stakeholders. This is particularly relevant in the tourism sector, which is a typical multistakeholder context. In the academic literature, few studies have investigated the role of the country‐specific determinants of corporate social responsibility, and none of them adopt a cross‐country approach. The objective of this paper is to analyze the disclosure of SE, observing the content of nonfinancial reports and company websites of all companies belonging to the Global Reporting Initiative database. Cross‐country analysis confirms that European and non‐European firms approach SE activities differently. The research offers a contribution to the development and improvement of company relations with stakeholders from a value cocreation perspective, identifying the areas of interest on which firms can work to advance the SE communication process.
The Hagfeldt Donor and Use of Next‐Generation Bulky Donor Designs in Dye‐Sensitized Solar Cells
Authors: Baumann Alexandra , Curiac Christine , Delcamp Jared H.
Published: February 2020

“The Hagfeldt donor” is a bulky triarylamine building block with four alkyl chains in a 3‐dimensional arrangement that is used with organic dyes in dye‐sensitized solar cells (DSCs) in over 140 publications. Many of the highest performing DSC devices in literature make use of this group due to exceptional TiO2 surface protection properties, which slows recombination of electrons in TiO2 with the electrolyte. Importantly, record‐setting cobalt and copper redox shuttle‐based DSCs require exceptional surface protection to slow a facile recombination of electrons to these positively charged redox shuttles. Several syntheses have emerged for the Hagfeldt donor due to the need for iterative aryl–halide cross‐ coupling reactions complicating a straightforward route. Six synthetic strategies found in literature are described along with the challenges of each route. A recent method that has been put forward in the literature as a scalable, regioisomerically pure route is highlighted.
CD40L reverse signaling suppresses prevertebral sympathetic axon growth and tissue innervation
Authors: Calhan Osman Yipkin , Wyatt Sean , Davies Alun Millward
Published: February 2020

CD40‐activated CD40L reverse signaling is a major physiological regulator of the growth of neural processes in the developing nervous system. Previous work on superior cervical ganglion (SCG) neurons of the paravertebral sympathetic chain has shown that CD40L reverse signaling enhances NGF‐promoted axon growth and tissue innervation. Here we show that CD40L reverse signaling has the opposite function in prevertebral ganglion (PVG) sympathetic neurons. During a circumscribed perinatal window of development, PVG neurons cultured from Cd40–/– mice had substantially larger, more exuberant axon arbors in the presence of NGF than PVG neurons cultured from wild‐type mice. Tissues that receive their sympathetic innervation from PVG neurons were markedly hyperinnervated in Cd40–/– mice compared with wild‐type mice. The exuberant axonal growth phenotype of cultured CD40‐deficient perinatal PVG neurons was pared back to wild‐type levels by activating CD40L reverse signaling with a CD40‐Fc chimeric protein, but not by activating CD40 forward signaling with CD40L. The co‐expression of CD40 and CD40L in PVG neurons suggests that these proteins engage in an autocrine signaling loop in these neurons. Our work shows that CD40L reverse signaling is a physiological regulator of NGF‐promoted sympathetic axon growth and tissue innervation with opposite effects in paravertebral and prevertebral neurons.
Density dependence forces divergent population growth rates and alters occupancy patterns of a central place foraging Antarctic seabird
Authors: Southwell Colin , Emmerson Louise
Published: February 2020

Density‐dependent regulation is an important process in spatio‐temporal population dynamics because it can alter the effects of synchronizing processes operating over large spatial scales. Most frequently, populations are regulated by density dependence when higher density leads to reduced individual fitness and population growth, but inverse density dependence can also occur when small populations are subject to higher extinction risks. We investigate whether density‐dependent regulation influences population growth for the Antarctic breeding Adélie penguin Pygoscelis adeliae. Understanding the prevalence and nature of density dependence for this species is important because it is considered a sentinel species reflecting the impacts of fisheries and environmental change over large spatial scales in the Southern Ocean, but the presence of density dependence could introduce uncertainty in this role. Using data on population growth and indices of resource availability for seven regional Adélie penguin populations located along the East Antarctic coastline, we find compelling evidence that population growth is constrained at some locations by the amount of breeding habitat available to individuals. Locations with low breeding habitat availability had reduced population growth rates, higher overall occupancy rates, and higher occupancy of steeper slopes that are sparsely occupied or avoided at other locations. Our results are consistent with evolutionary models of avian breeding habitat selection where individuals search for high‐quality nest sites to maximize fitness returns and subsequently occupy poorer habitat as population density increases. Alternate explanations invoking competition for food were not supported by the available evidence, but strong conclusions on food‐related density dependence were constrained by the paucity of food availability data over the large spatial scales of this region. Our study highlights the importance of incorporating nonconstant conditions of species–environment relationships into predictive models of species distributions and population dynamics, and provides guidance for improved monitoring of fisheries and climate change impacts in the Southern Ocean.
Do birds help trees grow? An experimental study of the effects of land‐use intensification on avian trophic cascades
Authors: Harris Scott H. , Kormann Urs G. , Stokely Thomas D. , Verschuyl Jake , Kroll Andrew J. , Betts Matthew G.
Published: February 2020

By regulating populations of herbivores, predators can indirectly influence plant production. However, the factors influencing the strength of this type of trophic cascade are still unclear. We hypothesized that changes to plant community structure would affect the number of avian predators, thereby mediating cascade strength. Using a 4‐yr, blocked, split‐plot experiment, we independently manipulated both predators (birds) and plants in an early seral managed forest system in western Oregon, USA, and measured abundance across three trophic levels. We applied herbicides, as a surrogate for land‐use intensification, to recently clear‐cut stands to establish an experimental gradient in plant abundance and species richness, and excluded birds using 28, 225 m2exclosures. In total, we counted and identified 94,738 arthropods of 141 families in paired control and bird exclosure plots. On average, insectivorous birds reduced arthropod abundance by 16% and plant damage by 14%, and some well‐known pests (e.g.,Adelges cooleyi) of crop trees (mostlyPseudotsuga menziesii) in our system were reduced by as much as 30%. However, this effect did not translate into a trophic cascade that increased crop‐tree growth in the presence of birds. We experimentally reduced plant abundance and diversity by 67% and 55%, respectively, in the most intensive herbicide treatment in relation to untreated controls, but reduced vegetative resources did not change the strength of the direct effect of birds on arthropods or the indirect effect of birds on plants.
High‐power microwave generation by double‐anode virtual cathode oscillator
Authors: Nagao Kazuki , Takatsu Wataru , Van Thuan Pham , Sugai Taichi , Jiang Weihua
Published: February 2020

The virtual cathode oscillator (vircator) is one of the promising devices to oscillate high‐power microwaves. Simplicity and high‐power capability are advantages. However, the low efficiency and frequency stability are serious problems. In this article, we dealt double anode to strengthen the microwave interactions. The measurement result shows that the output of the virtual cathode oscillator can be progress by using the double‐anode.
Double‐chambered right ventricle complicated by hypertrophic obstructive cardiomyopathy diagnosed as Noonan syndrome
Authors: Yamamoto Masahiro , Takashio Seiji , Nakashima Naoya , Hanatani Shinsuke , Arima Yuichiro , Sakamoto Kenji , Yamamoto Eiichiro , Kaikita Koichi , Aoki Yoko , Tsujita Kenichi
Published: February 2020

We present a case of double‐chambered right ventricle (DCRV) complicated by hypertrophic obstructive cardiomyopathy (HOCM) in KRAS mutation‐associated Noonan syndrome. The diagnosis was incidental and made during diagnostic testing for an intradural extramedullary tumour. Spinal compression, if not surgically treated, may cause paralysis of the extremities. We decided to pursue pharmacological therapy to control biventricular obstructions and reduce the perioperative complication rate. We initiated treatment with cibenzoline and bisoprolol; the doses were titrated according to the response. After 2 weeks, the peak pressure gradient of the two RV chambers decreased from 101 to 68 mmHg, and the LV peak pressure gradient decreased from 109 to 14 mmHg. Class 1A antiarrhythmic drugs and β‐blockers decreased the severe pressure gradients of biventricular obstructions caused by DCRV and HOCM. The patient was able to undergo surgery to remove the intradural extramedullary tumour, which was diagnosed as schwannoma.
Trends in cardiogenic shock complicating acute myocardial infarction
Authors: Aissaoui Nadia , Puymirat Etienne , Delmas Clément , Ortuno Sofia , Durand Eric , Bataille Vincent , Drouet Elodie , Bonello Laurent , Bonnefoy‐Cudraz Eric , Lesmeles Gilles , Guerot Emmanuel , Schiele Francois , Simon Tabassome , Danchin Nicolas
Published: February 2020

Aims

Few studies describe recent changes in the prevalence, management, and outcomes of cardiogenic shock (CS) patients complicating acute myocardial infarction (AMI) in the era of widespread use of invasive strategies. The aim of the present study was to analyse trends observed in CS complicating AMI over the past 10 years, focusing on the timing of CS occurrence (i.e. primary CS, CS on admission vs. secondary CS, CS developed subsequently during hospitalization).

Methods and results

Three nationwide French registries conducted and designed to evaluate AMI management and outcomes in ‘real‐life’ practice included consecutive AMI patients (n = 9951) admitted to intensive cardiovascular care units (ICCUs) over a 1‐month period, 5 years apart. The prevalence of CS complicating AMI decreased from 2005 to 2015: 5.9%, mean age 74.1 ± 12.7 in 2005; 4.0%, mean age 73.9 ± 12.7 in 2010, 2.8%, mean age 71.1 ± 15.0 in 2015 (P < 0.001). It decreased for both primary (1.8% to 1.0%) and secondary CS (4.1% to 1.8%). The profile of CS patients also changed over time with more patients presenting out‐of‐hospital cardiac arrest. In both primary and secondary CS, the use of percutaneous coronary intervention increased markedly over time, as did the use of mechanical ventilation and cardiac assist devices. Over the 10‐year period, in‐hospital mortality remained unchanged for both primary CS (41.8% to 37.8%) or secondary CS (57.3% to 58.8%). However, 1‐year mortality decreased in patients with primary CS (from 60% to 37.8%, P = 0.038), and remained unchanged in patients developing secondary CS (from 64.5% to 69.1%, P = 0.731).

Conclusion

Cardiogenic shock complicating AMI has become less frequent but, if present, CS, and particularly secondary CS, carries a very high mortality, which has not substantially improved over the past 10 years, in spite of the more frequent use of invasive strategies.
Light‐chain and transthyretin cardiac amyloidosis in severe aortic stenosis: prevalence, screening possibilities, and outcome
Authors: Nitsche Christian , Aschauer Stefan , Kammerlander Andreas A. , Schneider Matthias , Poschner Thomas , Duca Franz , Binder Christina , Koschutnik Matthias , Stiftinger Julian , Goliasch Georg , Siller‐Matula Jolanta , Winter Max‐Paul , Anvari‐Pirsch Anahit , Andreas Martin , Geppert Alexander , Beitzke Dietrich , Loewe Christian , Hacker Marcus , Agis Hermine , Kain Renate , Lang Irene , Bonderman Diana , Hengstenberg Christian , Mascherbauer Julia
Published: February 2020

Aims

Concomitant cardiac amyloidosis (CA) in severe aortic stenosis (AS) is difficult to recognize, since both conditions are associated with concentric left ventricular thickening. We aimed to assess type, frequency, screening parameters, and prognostic implications of CA in AS.

Methods and results

A total of 191 consecutive AS patients (81.2 ± 7.4 years; 50.3% female) scheduled for transcatheter aortic valve replacement (TAVR) were prospectively enrolled. Overall, 81.7% underwent complete assessment including echocardiography with strain analysis, electrocardiography (ECG), cardiac magnetic resonance imaging (CMR), 99mTc‐DPD scintigraphy, serum and urine free light chain measurement, and myocardial biopsy in immunoglobulin light chain (AL)‐CA. Voltage/mass ratio (VMR; Sokolow–Lyon index on ECG/left ventricular mass index) and stroke volume index (SVi) were tested as screening parameters. Receiver operating characteristic curve, binary logistic regression, and Kaplan–Meier curve analyses were performed. CA was found in 8.4% of patients (n = 16); 15 had transthyretin (TTR)‐CA and one AL‐CA. While global longitudinal strain by echo did not reliably differentiate AS from CA‐AS [area under the curve (AUC) 0.643], VMR as well as SVi showed good discriminative power (AUC 0.770 and 0.773, respectively), which was comparable to extracellular volume by CMR (AUC 0.756). Also, VMR and SVi were independently associated with CA by multivariate logistic regression analysis (P = 0.016 and P = 0.027, respectively). CA did not significantly affect survival 15.3 ± 7.9 months after TAVR (P = 0.972).

Conclusion

Both TTR‐ and AL‐CA can accompany severe AS. Parameters solely based on ECG and echocardiography allow for the identification of the majority of CA‐AS. In the present cohort, CA did not significantly worsen prognosis 15.3 months after TAVR.
A Sensitive Electrochemical Sensor Based on Graphene Oxide Nanosheets Decorated by Fe3O4@Au Nanostructure Stabilized on Polypyrrole for Efficient Triclosan Sensing
Authors: Saljooqi Asma , Shamspur Tayebeh , Mostafavi Ali
Published: February 2020

Triclosan is broadly utilized as preservative or antiseptic in various cosmetic and personal care products. It becomes hazardous for environmental safety and human health more than a certain concentration. In this research, graphene oxide (GO) nanosheets were prepared by composing Fe3O4@Au nanostructure decorated GO together with polypyrrole (PPy) (Fe3O4@Au‐PPy/GO nanocomposite) in a facile way. The composite excellent increased the electrochemical response, presenting a high sensitive electrochemical method for triclosan detection. The synthesized Fe3O4@Au‐PPy/GO nanocomposite was characterized for its morphological, magnetically and structural properties by FESEM‐mapping, TEM, and XRD. The Fe3O4@Au‐PPy/GO nanocomposites modified glassy carbon electrodes (GCE), Fe3O4@Au‐PPy/GO GCE, showed a higher sensitivity good stability, reproducibility, lower LOD (2.5×10−9 M) and potential practical application in electrochemical detection of triclosan under optimized experimental conditions.
Neural network modeling and simulation of the synthesis of CuInS2/ZnS quantum dots
Authors: Fu Min , Mrziglod Thomas , Luan Weiling , Tu Shan‐Tung , Mleczko Leslaw
Published: February 2020

The development of recipes for synthesis of quantum dots (QDs), a novel semiconductor material for application in optoelectronic devices, is currently purely based on experiments. Since the quality of QDs represented by quantum yield (QY) and emission peak strongly depends on a number of different parameters (route, precursors, conditions, etc), a large number of experiments is necessary. In this article, we show that data‐driven modeling can be used as a supporting tool for optimization and a better understanding of the synthesis process. By using the results collected during the development of CuInS2/ZnS (CIS/ZnS) QDs, a neural network model has been established. The model is able to predict the optical properties (QY and emission peak) of CIS/ZnS QDs as a function of the most important synthesis parameters, such as reaction temperature, time of CIS core formation and ZnS shell growth, feed molar ratio of Cu/In and Zn/Cu, various starting precursors, and types of ligands. Finally, a model analysis under various effects influencing the quality of QDs is performed.
Large‐Scale Synthesis of Nitrogen‐Doped Activated Carbon Fibers with High Specific Surface Area for High‐Performance Supercapacitors
Authors: Liao Ming Dong , Peng Chuan , Hou Sheng Ping , Chen Jian , Zeng Xian Guang , Wang Hao-Lun , Lin Jarrn-Horng
Published: February 2020

Activated carbon nanofibers (ACFs) with high specific surface area, excellent conductivity, and narrow pore‐size distribution, are regarded as a promising electrode material for high‐performance supercapacitors (SCs). Herein, a facile route to synthesize large‐scale amorphous CF (a‐CF) using catalytic pyrolysis of acetylene (C2H2) at 260 °C over copper catalysts is reported. The conversion rate of acetylene into a‐CF is estimated as high as 72.05 wt%. Subsequently, the as‐prepared a‐CF is transformed into ACFs by potassium hydroxide (KOH) at 800 °C with high specific surface area and porous structures. Moreover, nitrogen‐doped ACFs are conducted in the activation step through a physical mixing of a‐CF/KOH/melamine with various ratios. For SCs, the as‐prepared N‐ACFs display excellent specific capacitance and cycle stability. In the three‐electrode system, the N‐ACF (CF‐03) demonstrates a specific capacitance value of 227 F g−1 at 0.5 A g−1, and shows a 94% capacitance retention after a long cycle (10 000 cycles) at 2 A g−1. Moreover, the CF‐03‐based two‐electrode SC demonstrates a high energy density of 14.30 Wh kg−1 and a high power density of 79.88 W kg−1 in 1 m Na2SO4 electrolyte. Herein, a simple and promising way to prepare large‐scale a‐CF, ACF, and N‐doped ACFs is demonstrated.
Assessment of exopolysaccharide production by Lactobacillus delbrueckii subsp. bulgaricus ropy strain in different substrate media
Authors: Malaka Ratmawati , Maruddin Fatma , Dwyana Zaraswati , Vargas Maynor V.
Published: February 2020

The aim of this research was to determine the optimal medium for Exopolysaccharides (EPS) production by a Lactobacillus delbrueckii subsp. bulgaricus ropy strain isolated from a locally produced commercial fermented milk, in reconstituted skim milk (RSM) 10% (w/v), milk whey (MW), and soy milk whey (SMW), under optimal growth conditions for this strain. Milk whey was made by coagulating fresh milk using papaya latex 3% (v/v); soy milk whey was obtained from tofu household industry. The chemical composition of the substrate media was determined by proximate analysis, and sterilization was accomplished in an autoclave at 121°C for 15 min. Culture media were inoculated with 1% (v/v) of a starter culture of L. delbrueckii subsp. bulgaricus and then incubated at 30°C for 16 hr. EPS production, lactic acid content, cell counting, and pH were determined after the media were cooled at 5°C. Findings showed that on the basis of the growth characteristics of L. delbrueckii subsp. bulgaricus, the best medium for EPS production was RSM 10% (258.60 ± 26.86 mg/L) compared to the milk whey (69.60 ± 9.48 mg/L) and soy milk whey (49.80 ± 9.04 mg/L).
Food functionalities and bioactivities of protein isolates recovered from skipjack tuna roe by isoelectric solubilization and precipitation
Authors: Cha Jang Woo , Yoon In Seong , Lee Gyoon‐Woo , Kang Sang In , Park Sun Young , Kim Jin‐Soo , Heu Min Soo
Published: February 2020

Four roe protein isolates (RPIs) from skipjack tuna were prepared using isoelectric solubilization (pH 11 and 12) and precipitation (pH 4.5 and 5.5) (ISP) at different pH points to evaluate their physicochemical and functional properties and in vitro bioactivities. Moisture (<6.3%) and protein (71%–77%) content were maintained. Sulfur, sodium, phosphorus, and potassium were the major elements, and glutamic acid and leucine were the prevalent amino acids (12.2–12.8 and 9.6–9.8 g/100 g protein, respectively) in RPIs. RPI‐1 showed the highest buffering capacity at pH 7–12. RPIs and casein showed similar water‐holding capacities. At pH 12, RPI‐1(pH 11/4.5) showed the highest solubility, followed by RPI‐3(pH 12/4.5), RPI‐2(pH 11/5.5), and RPI‐4(pH 12/5.5) (p < .05). Oil‐in‐water emulsifying activity indices of RPI‐1 and RPI‐3 significantly differed. At pH 2 and 7–12, pH‐shift treatment improved the food functionality of RPIs, which was superior to positive controls (casein and hemoglobin). RPI‐1 showed ABTS+ radical scavenging (102.7 μg/ml) and angiotensin‐converting enzyme inhibitory activities (44.0%).
Evaluation of Metals in Soil and Tissues of Economic-Interest Plants Grown in Sites Affected by the Fundão Dam Failure in Mariana, Brazil
Authors: Coelho Daniel Gomes , Marinato Claudio Sergio , de Matos Letícia Paiva , de Andrade Heloísa Monteiro , da Silva Vinicius Melo , Neves Pedro Henrique Santos , de Oliveira Juraci Alves
Published: February 2020

The objective of this study was to evaluate the concentration of potentially toxic elements in Brachiaria decumbens, Stylosanthes guianensis, and Saccharum officinarum plants and soil samples in affected and unaffected areas by rupture of the Fundão dam, Brazil. Samples were collected in areas affected by residues from the Fundão dam (RAA1, RAA2, RAA3) and in an unaffected area (control). The material was analyzed for the composition of micronutrients and trace elements in soil and plants, as well as contamination factor (CF), accumulation factor, and translocation factor (TF). Overall, the results showed that soil and plant tissues had increased Fe, Mn, Cu, and Cr content and decreased Zn content in the affected areas, compared to the control. Leaves and roots of B. decumbens showed an increase in Fe content in affected areas, compared to the control, reaching a mean maximum value of 42 958 µg/g of roots of RAA2-collected plants. As a result, CF for Fe of B. decumbens was classified as very high and they presented low TF values. Furthermore, B. decumbens collected in affected areas showed an increase of Fe, Mn, Cu, and Cr in leaves, stems, and roots, whereas in Stylosanthes guianensis, there was an increase of Fe concentration in all tissues and Cr in leaves. Also, Saccharum officinarum showed the accumulation of Mn in the stem and Cu in leaves and stem. On the other hand, there was no contamination of plants by hazardous elements such as Pb, Cd, and As in the samples analyzed. In conclusion, increases in the content of Fe, Mn, Cu, and Cr were found in soil and several plant tissues of residue-affected areas, which could compromise plant growth and represent potential hazards arising from the biomagnification process in the food chain. Integr Environ Assess Manag 2020;16:596–607. © 2020 SETAC