bluuebunny/crossref_metadata_2025 huggingface dataset:
Acrylic‐ester‐polyol based novel two‐component polyurethane clear coat: Evaluation of performance characteristics
Authors: Mohanty Smruti Ranjan , Mohanty Smita , Samal Sushanta K. , Nayak Sanjay K.
Published: April 2021

In the current study, a combination of acrylic polyol (AP) and ester polyol (EP) were synthesized and reacted at variable ratios with hexamethylene diisocyanates and isophorone diisocyanates to prepare a transparent two‐component polyurethane (PU) coating formulation. The formations of the polyol system, isocyanate system, and the PU systems were confirmed by 1H nuclear magnetic resonance and Fourier‐transform infrared spectroscopy. Transparency of the coatings was examined using haze, and gloss measurement, which showed acrylic‐ester‐polyurethane (aePU‐5 and aePU‐6) have 91.5% and 91.8% transparency and gloss of 90.3 and 90.7 GU respectively. The thermal properties like Tg and the thermal stability of the coatings were verified using differential scanning calorimetry, and thermogravimetric analysis respectively which was found to increase with increasing EP content and decreasing AP content which may be ascribed to improved compatibility of copolymers, and homogeneity in PU along with enhanced crosslinking density. The degree of adhesion of coating with the substrate was validated from lap‐shear, and cross‐cut tape test which showed improved performance at AP:EP ratio of 60:40. The coatings were found to exhibit resistance toward pencil hardness with aePU‐5 and aePU‐6 having the optimum resistance of 9H. The surface morphology and topography were observed under scanning electron microscopy, and atomic force microscopy, respectively. The outcome confirms the higher smoothness of the surfaces subjected to the increase in EP content. The PU system with 40 wt% AP content and 60 wt% EP designated as aePU‐5 was found to exhibit optimum performance.
On the nonisothermal melt crystallization kinetics of industrial batch crosslinked polyethylene
Authors: Coutinho Suellen Veloso Côrte Real , de Sousa Barros Ana Beatriz , Pereira Barros Janetty Jany , Albuquerque Ananda Karoline Calvacanti , Barreto José Vinícius Melo , Siqueira Danilo Diniz , Ries Andreas , Wellen Renate Maria Ramos
Published: April 2021

The chemical modification of commodity polymers such as polyethylene (PE) is a versatile synthetic approach for preparing materials that cannot be manufactured cost‐effectively using conventional polymerization techniques. Aiming to improve PE character low contents of dicumyl peroxide (DCP), from 0% to 1.5% was added as crosslinker to an industrial batch (PEs mixture and additives). From tensile testing crosslinking provided higher elastic modulus most due to the restrained microstructure where XPEs macromolecular chains are interconnected also providing lower strain at break. Crosslinking effects on the nonisothermal melt crystallization rate (Cmax) and degree of crystallinity (Xc) were evaluated; Cmax increased with the cooling rates, whereas Xc increased upon DCP addition. The melt crystallization kinetics were thoroughly investigated applying Pseudo‐Avrami, Ozawa, and Mo models. Ozawa failed to describe the crystallization most due to ignore the secondary crystallization and spherulites impingement at the end of crystallization while Pseudo‐Avrami and Mo provided quite good fits. The activation energy was computed using Arrhenius' approach, crosslinked compounds presented higher energy consumption, whereas exception was verified for 0.5XPE which displayed the lowest energy and overall the best mechanical performance this is the most proper compound for industrial applications, such as packaging, and disposables as well as general goods.
Functional nano‐fillers in waterborne polyurethane/acrylic composites and the thermal, mechanical, and dielectrical properties
Authors: Zhou Xing , Song Yonghua , Wang Dong , Fang Changqing , Xie Li , Yao Taiping , Zhang Xin , Zhang Jiawei
Published: April 2021

Modification is mostly used to adjust and increase the performance of polymers by employing organic or inorganic fillers in composites. It is significant to investigate the functions of different fillers in polymer matrix. In this work, we prepared a series of composites by using polyurethane/acrylic dispersions as polymer matrix and nanofillers (cellulose nanocrystals, carbon nanotubes and aluminum oxide nanoparticles) as modifiers to study their micro‐structure and applied performance. It is found that the different nanofillers can be dispersed in PUA homogenously, which are inclusive physically. Different nanofillers have a noticeable influence on the Tg for the acrylate copolymers and the Tg of the interphase between the acrylate and polyurethane. The CNTs significantly increases the elongation to 127.29%, and gives the highest dielectric response. We imply that the CNTs may be the most significant fillers to increase the mechanical and electrical properties.
Water‐repellent films from corn protein and tomato cutin
Authors: Hood Christine , Laredo Thamara , Marangoni Alejandro G. , Pensini Erica
Published: April 2021

Flexible and hydrophobic biobased films were obtained using zein esterified with methanol and para‐toluene (p‐toluene) sulfonic acid, cutin from tomato peels and ethanol. Esterification was confirmed by proton nuclear magnetic resonance and attenuated total reflectance–Fourier transform infrared spectroscopy (ATR‐FTIR). Non‐modified zein films were brittle and hydrophilic. ATR‐FTIR demonstrated that zein esterification increased zein hydrophobicity. Without cutin, esterified zein films were hydrophobic but brittle. Addition of cutin yielded films that were flexible and hydrophobic, as demonstrated by contact angle measurements. Principal component analysis (PCA) of ATR‐FTIR data showed that intensities at 3195 cm−1 and 3490 cm−1 were correlated to the relative hydrophobicity of zein films. PCA also showed that films of esterified zein and cutin were more hydrophobic than their counterparts (non‐modified zein without cutin). Optical and scanning electron microscopy demonstrated that esterified zein was compatible with cutin and yielded cohesive films, which did not fracture upon bending.
Evaluating candidate wetlands for the assisted colonization of the western swamp turtle Pseudemydura umbrina in a changing climate: Macro‐invertebrate food resources and turtle diet
Authors: Schmölz Katja , Pinder Adrian , Kuchling Gerald , Gollmann Günter
Published: April 2021

The natural habitat of the western swamp turtle (Pseudemydura umbrina Siebenrock, 1901) – the ephemeral, winter wet swamps north of Perth, Australia – is in danger owing to climate change and habitat fragmentation. The decline in rainfall in this area over the last five decades is predicted to continue, shortening the annual activity period for the turtles and potentially shifting their optimal climate zone to the south.

Assisted colonization to wetlands in the cooler far south west of the state is one management response. As a contribution to such a measure, the diversity and abundance of food resources and consumption by turtles were evaluated at two potential and one existing colonization site.

Thirty‐five captive‐bred juvenile P. umbrina were temporarily released into three sites: Moore River Nature Reserve north of Perth (into which the species had already been successfully translocated) and Meerup and East Augusta in the cooler far south of Western Australia.

Food resources were assessed using sweep nets to sample invertebrates on two occasions at each wetland. Separate samples were collected for biomass determination and for assessing invertebrate diversity. Feeding by turtles was assessed by stomach flushing.

Neither biomass nor biodiversity differed significantly between the southern sites and the reference site north of Perth. Stomach contents varied greatly, from 0 to 62 animals per turtle. The main prey items were beetles, ostracods, isopods and tadpoles.

Each candidate wetland provided adequate food resources, indicating that assisted colonization to the cooler south coast of Western Australia has the potential to become a reasonable conservation tool to ensure the long‐term survival of P. umbrina.
Hobbyists acting simultaneously as anglers and aquarists: Novel pathways for non‐native fish and impacts on native fish
Authors: Hirsch Philipp Emanuel , N'Guyen Anouk , Burkhardt‐Holm Patricia
Published: April 2021

Human translocations of non‐native aquatic species are a global conservation challenge. Aquarists and anglers are two hobbyist groups whose practices are particularly likely to translocate non‐native aquatic species, especially fish.

This article aims to stipulate a change of perspective among these hobbyists, who – by acting simultaneously as anglers and aquarists – establish novel pathways for non‐native fish.

This study showed that: (i) 51 of 226 respondents to a questionnaire act simultaneously as anglers and aquarists; (ii) 53 of 237 non‐native fish species in the European Union are used for both angling and aquarium hobbies; and (iii) hobbyists write online reports on the catch and exchange of a particularly invasive fish, the round goby (Neogobius melanostomus).

This combination of knowledge on how hobbyists use non‐native fish and the ecological impacts of round goby demonstrates how the impact of an invasive species can be influenced by the combined behaviours of anglers and aquarists.

We suggest that future research in aquatic conservation should move beyond considering the commercial aquarium trade and angling as separate pathways for translocating non‐native fish, and instead consider these hobbyist groups as interconnected.
Liquid‐Crystal Mediated Assembly of Iodinated Graphene Oxide for Ultra‐Dense Supercapacitors as Safe Power Source for Internet of Things Data Transmission
Authors: Mirshekarloo Meysam Sharifzadeh , Cooray M. C. Dilusha , Jovanović Petar , Easton Christopher D. , Wu Fan , Gamot Tanesh D. , Abedin Md. Joynul , Yuce Mehmet Rasit , Shaibani Mahdokht , Majumder Mainak
Published: April 2021

Dense iodinated reduced graphene oxide (rGO) with outstanding electrical and electrochemical properties is produced through a green method comprising liquid crystal‐mediated assembly of polyiodides and GO, and subsequent UV irradiation. The dense rGO electrode (1.46 g/cm3) exhibited a very high volumetric capacitance of 226 F/cm3, a factor of three larger than commercial activated carbon, and amongst the highest reported for graphene. The scalability is demonstrated by the fabrication of supercapacitor pouch cells that realized a volumetric energy density of 0.94 Wh/l, comparable to market products with similar footprint, while advantageously using a safe and green aqueous electrolyte. Our pouch cell powered battery‐less Internet of Things (IoT) sensor nodes and demonstrated sensing and transmission of over 40 temperature and relative humidity data packets. Our work establishes the critical advantages graphene‐based materials have over activated carbons in terms of ease of fabrication, tailorability, and enhanced volumetric energy density to advance the state‐of‐art in supercapacitor device research.
Betontechnologische Einflüsse auf die Leistungsklassen von Stahlfaserbeton
Authors: Weber Fabian , Orben Jeannette , Haus Andreas , Anders Steffen
Published: April 2021

Die Leistungsfähigkeit von Stahlfaserbeton, ausgedrückt durch seine Leistungsklassen und damit die erreichten Nachrissbiegezugfestigkeiten, hängt von zahlreichen Faktoren ab. Dazu zählen beispielsweise die Betondruckfestigkeit, Faserart und ‐geometrie, der Fasergehalt und die Betonzusammensetzung. Im Rahmen der Arbeit im Unterausschuss Stahlfaserbeton des DAfStb wurde mit der Biegebalken‐Datenbank „Stahlfaserbeton” eine sehr umfangreiche Datenbank mit Erst‐ und Bestätigungsprüfungen an Stahlfaserbetonen aus der Literatur und Praxis aufgebaut. Sie ermöglicht es, unterschiedliche Einflüsse, z. B. aus der Betonzusammensetzung oder den Fasereigenschaften, allgemein zu quantifizieren. In diesem Beitrag werden die Einflüsse der Faserzugfestigkeit, der Schlankheit der Fasern, der Betondruckfestigkeit, üblicher Einbaukonsistenzen, der Form der Gesteinskörnung sowie die Verwendung sekundärreaktiver Zusätze betrachtet. Auf Grundlage der Datenbank kann gezeigt werden, dass im Allgemeinen gebrochene Gesteinskörnung im Vergleich zu runder Gesteinskörnung sowie die Einbaukonsistenzen F3 und F4 keinen erkennbaren Effekt auf die Nachrissbiegezugfestigkeit zeigen. Bei der Verwendung sekundärreaktiver Stoffe wie hüttensandhaltige Zemente oder Flugaschen lässt sich aus der Datenbank eine deutliche Erhöhung der Nachrissbiegezugfestigkeiten ablesen. Die positiven Einflüsse der Betondruckfestigkeit und der Faserschlankheit können verallgemeinert bestätigt und quantifiziert werden.
Can Precision Electrophile Signaling Make a Meaningful and Lasting Impression in Drug Design?
Authors: Long Marcus J. C. , Kulkarni Amogh , Aye Yimon
Published: April 2021

For several years, drugs with reactive electrophilic appendages have been developed. These units typically confer prolonged residence time of the drugs on their protein targets, and may assist targeting shallow binding sites and/or improving the drug–protein target spectrum. Studies on natural electrophilic molecules have indicated that, in many instances, natural electrophiles use similar mechanisms to alter signaling pathways. However, natural reactive species are also endowed with other important mechanisms to hone signaling properties that are uncommon in drug design. These include ability to be active at low occupancy and elevated inhibitor kinetics. Herein, we discuss how we have begun to harness these properties in inhibitor design.
Can a self‐expanding pediatric stent expand with an artery? Relationship of stent design to vascular biology
Authors: Nia Nima V. , Fishbein Gregory A. , Levi Daniel S.
Published: April 2021

Objectives

A large‐diameter, intravascular, self‐expanding stent system capable of continued expansion during somatic and vascular growth was modeled with finite element analysis (FEA), manufactured and tested in an animal model.

Background

Children can quickly outgrow intravascular stents. If a stent could expand after implantation in arteries this would be ideal for use in pediatric patients.

Methods

Computer‐aided design and FEA were used to design and manufacture large‐diameter, self‐expanding nitinol stents with both high and low chronic outward force (COF). Four distinct stents with similar designs but with variable lengths and strut thicknesses were manufactured. Fourteen of these stents were implanted in the abdominal aortas or iliac arteries of four juvenile swine.

Results

All animals survived without complication to their designated time points of harvest (90 or 180‐days), and all stents expanded to greater diameters than the adjacent non‐stented artery. Luminal diameter growth was 34–49% and 20–23% for stented and non‐stented segments, respectively. Histologic examination revealed variable degrees of the internal elastic lamina and/or medial disruption with a mean injury score ranging from 0.70 ± 0.56 to 1.23 ± 0.21 and low COF stents implanted in smaller arteries having a larger injury score. Inflammatory responses and stenosis formation were minimal and ranged from 0.50 ± 0.71 to 3.00 ± 0.00 and 5.52 ± 1.05% to 14.68 ± 9.12%, respectively. The stent's COF did not correlate with vessel expansion or vascular injury.

Conclusions

Self‐expanding stents can mirror and even exceed somatic growth. Although longer‐term testing is needed, it may be possible to custom tailor self‐expanding stents to expand after arterial implantation in pediatric patients.
Lorlatinib‐induced visual and auditory hallucinations: A case report
Authors: Hakamata Jun , Nakada Hideo , Muramatsu Hiroshi , Masuzawa Keita , Terai Hideki , Ikemura Shinnosuke , Fukunaga Koichi , Aomori Tohru
Published: April 2021

Lorlatinib can cause visual and auditory hallucinations. And, it is necessary to keep in mind that hallucinations can persist even after discontinuation in patients who develop hallucinations while receiving lorlatinib.
Colloidal processing and characterization of TiO2–MnO‐doped alumina/alumina slurries and tapes
Authors: Daniel Barros Marcelo , Hotza Dachamir , Janssen Rolf
Published: April 2021

Aqueous slurries of alumina doped with manganese and titanium oxides were developed. The powders and tapes were investigated by scanning electron (SEM) microscopy, X‐ray diffractometry (XRD), and thermal analyses (TG/DSC). The stability and rheology of colloidal suspensions of undoped and doped alumina suspensions were investigated. At neutral pH of 7, pure alumina and MnO–TiO2 dopant particles present positive and negative surface charges and are prone to heterocoagulation. Optimized colloidal processing through proper adjustment of parameters was achieved to reach particle stabilization. The surface charge of the oxide particles was negative, and the suspensions did not agglomerate at a pH of 7 and higher. Tapes were cast, dried, and burned out. The thermal analyses revealed the release of residual water and decomposition of short‐chain organics at temperatures under 215°C and of long‐chain additives over 300°C.
Racemic Tartrate/Malate Anions Combine with Racemic Complex Cations to Form Optically Active Ionic Crystals
Authors: Uno Masashi , Kojima Tatsuhiro , Kuwamura Naoto , Yoshinari Nobuto , Konno Takumi
Published: April 2021

Spontaneous resolution has attracted continuing attention in various research fields since Pasteur's work on the crystallization behavior of racemic tartrate. Here, a unique example of this phenomenon is reported, involving ionic crystals generated from racemic RR/SS‐ tartrate or R/S‐malate and racemic ΔΔ/ΛΛ‐[Ag3Rh2(2‐aminoethanethiolato)6]3+ (ΔΔ/ΛΛ‐[1]3+) in water. RR‐ and SS‐tartrate selectively recognize the ΛΛ and ΔΔ isomers of [1]3+ to produce ionic crystals of (ΛΛ‐[1])2(RR‐tartrate)3 and (ΔΔ‐[1])2(SS‐tartrate)3, respectively, which can undergo spontaneous resolution. While spontaneous resolution also occurs when using R/S‐malate, R‐ and S‐malate select the opposite isomers of [1]3+ to give ionic crystals of (ΔΔ‐[1])2(R‐malate)3 and (ΛΛ‐[1])2(S‐malate)3, respectively. In the presence of S‐aspartate, (ΛΛ‐[1])2(R‐tartrate)3 and (ΔΔ‐[1])2(S‐tartrate)3 are preferentially crystallized from ΔΔ/ΛΛ‐[1]3+ and RR/SS‐tartrate at solution pH values of 6 and 10, respectively. This finding provides significant insight into the optical resolution of chemical species by spontaneous resolution and the origin of homochirality in nature.
Iridium Complex of N‐Fused Bilatrienone: Oxidative Cleavage of N‐Fused Porphyrin Induced by Iridium‐Cyclooctadiene Complexation
Authors: Abraham Jibin Alex , Mori Shigeki , Ishida Masatoshi , Furuta Hiroyuki
Published: April 2021

N‐fused porphyrin (NFP) is a unique class of photostable near‐infrared dyes with an 18π aromatic tetrapyrrole macrocyclic skeleton containing a tri‐fused pentacyclic moiety. Here, the synthesis of an iridium complex of N‐fused bilatrienone is reported as the degradation product of Ir‐cyclooctadiene (cod)‐induced oxidative cleavage of NFP under aerobic conditions. Similar to the native bilin chromophores, the ring‐opened complex featured a broken π‐conjugation circuit and exhibited a broad visible absorption band. In contrast, metalation of NFP using an iridium(I)(cod) complex under an inert atmosphere resulted in the formation of a cod‐isomerized (κ1,η3‐C8H12)‐Ir complex.
Metal‐Free Hydrosilylation of Ketenes with Silicon Electrophiles: Access to Fully Substituted Aldehyde‐Derived Silyl Enol Ethers
Authors: Roy Avijit , Oestreich Martin
Published: April 2021

Little‐explored hydrosilylation of ketenes promoted by main‐group catalysts is reported. The boron Lewis acid tris(pentafluorophenyl)borane accelerates the slow uncatalyzed reaction of ketenes and hydrosilanes, thereby providing a convenient access to the new class of β,β‐di‐ and β‐monoaryl‐substituted aldehyde‐derived silyl enol ethers. Yields are moderate to high, and Z configuration is preferred. The corresponding silyl bis‐enol ethers are also available when using dihydrosilanes. The related trityl‐cation‐initiated hydrosilylation involving self‐regeneration of silylium ions is far less effective.
The European Federation for Medicinal Chemistry and Chemical Biology (EFMC) Best Practice Initiative: Phenotypic Drug Discovery
Authors: Quancard Jean , Bach Anders , Cox Brian , Craft Russell , Finsinger Dirk , Guéret Stéphanie M. , Hartung Ingo V. , Laufer Stefan , Messinger Josef , Sbardella Gianluca , Koolman Hannes F.
Published: April 2021

Phenotypic drug discovery has a long track record of delivering innovative drugs and has received renewed attention in the last few years. The promise of this approach, however, comes with several challenges that should be addressed to avoid wasting time and resources on drugs with undesired modes of action or, worse, false‐positive hits. In this set of best practices, we go over the essential steps of phenotypic drug discovery and provide guidance on how to increase the chance of success in identifying validated and relevant chemical starting points for optimization: selecting the right assay, selecting the right compound screening library and developing appropriate hit validation assays. Then, we highlight the importance of initiating studies to determine the mode of action of the identified hits early and present the current state of the art.
Oncofertility Information Available for Recently Approved Novel Non Cytotoxic and Immunotherapy Oncology Drugs
Authors: Volckmar Xanthie , Vallejo Marcus , Bertoldo Michael J. , Nguyen Quynh‐Nhu , Handelsman David J. , Chisholm Orin , Anazodo Antoinette
Published: April 2021

We reviewed the available animal and human reproductive function studies of recently approved noncytotoxic oncology drugs. We reviewed the oncofertility information in the prescribing information for the US Food and Drug Administration (FDA)‐approved products and/or the product information and consumer medicine information for Therapeutic Goods Administration (TGA)‐approved drugs of 32 novel oncology drugs approved between 2014 and 2018 in the United States and/or Australia supplemented by a literature review for additional reproductive effects. No human studies were available on the reproductive effects of all 32 drugs. A systematic literature review of animal reproductive toxicity studies provided only very limited data with nine drugs displaying impaired male fertility, three impaired female fertility, and nine producing impaired fertility in both male and female animals. Two drugs in the study are reported to have no demonstrable impact on fertility in animal reproductive toxicity studies and nine are reported to have unknown effects on fertility. Of the 32 newly listed drugs, only 4 had recommendations regarding potential human fertility risks and accordingly advised clinicians about fertility preservation procedures for patients. The lack of human data and limited animal reproductive toxicity data raises concerns about the potential impact of these novel oncology drugs on human fertility and reproductive function. Consequently, adequate oncofertility recommendations, including for fertility preservation procedures, counselling for psychological or cost implications, and future prognosis for fertility are hindered by this paucity of relevant data. More data on human reproductive effects of novel oncology drugs is urgently required to facilitate effective use of the growing array of oncofertility care options available.
Fluorescent energy transfer causing misleading signal in multicolor flow cytometry
Authors: Khenine Hana , Waeckel Louis , Seghrouchni Fouad , Berger Anne‐Emmanuelle , Lambert Claude
Published: April 2021

Multiple immunolabeling introduces high risks of interferences between fluorochromes. In an intend to analyze T cell clonality using CD3‐APC Alexa750, CD4‐Pac Blue, CD8‐Krome Orange, CD56‐PE‐Cy7 and Vbeta clonotypes FITC and PE, we repeatedly observed a clear, unexpected signal on B770 (PE‐Cy7) detector on the Vb subset mimicking a lymphoproliferative disorder. The aim of this study was to identify and prevent this source of artifact. The study was performed on a seven color panel performed on fresh whole blood, labeled, fixed, lyzed and analyzed on Navios Cytometer Beckman Coulter. Data were reanalyzed using Kaluza. Eleven tubes tested two clonotypes each with the same T cell backbone. Only one representative combination is presented. Using this panel, we observed repeatedly a strong CD56 PE‐Cy7 (B755 LP) on all Vbeta1 T cell subsets but not on Vbeta 2‐FITC T cells. The effect was still observed after removing CD56‐PE‐Cy7 (Full Minus One). Changing anti‐CD3 APC‐Alexa 750 with CD3APC, the B755 LP signal disappeared but a B695/30 signal appeared. Shifting to CD3‐FITC abolished any unexpected red signal. This demonstrates a fluorescent energy transfer (FRET) between PE excited by the blue laser and Alexa750 to be excited by the red laser. Accordingly, the Vbeta PE fluorescence intensity was reduced when FRET happened and clearly increased when CD3‐FITC was used instead. This observation clearly reminds that FRET can give misleading results in case of labeling of very close markers with complementary fluorochromes. This risk has to be considered in panel design.
Enriched cluster head selection using augmented bifold cuckoo search algorithm for edge‐based internet of medical things
Authors: Anguraj Dinesh Kumar , Thirugnanasambandam Kalaipriyan , R.S Raghav , S.V Sudha , D. Saravanan
Published: April 2021

Healthcare organizations are appending advanced scientific tools for processing digital data effectively due to enterprise demands. Among the recent tools, edge computing plays a vital role in aggregation and dissemination of data from the healthcare monitoring devices. A vital challenge in edge computing‐based Internet of Medical Things (IoMT) systems are energy‐efficient monitoring devices which in turn improves the overall lifetime of the network thus in turn improves the quality of monitoring system. In recent years, a significant number of approaches are developed for solving energy efficient communication protocols for IoMT. Clustering is one effective method to reduce the overall energy consumption by the medical wireless devices. The major drawback of the existing models is the sustainability of the network. In this paper, an evolutionary‐based cluster head selection technique is proposed, namely, augmented bifold cuckoo search algorithm (ABCSA). A novel binary model is also developed for handling the binary solution space. The experimental analysis of the proposed model has been evaluated and compared with the existing model to prove it significance. And as a result on comparing with the existing models, proposed ABCSA outperforms the existing models significantly.
Genesis of sediment‐hosted stratiform Cu–Co deposits of the Zambia Copperbelt: Geochemistry and S–Pb isotopes constraints from the Chambishi deposit
Authors: Liu Chun‐Fa , Qing Min , Liu Shu‐Fei , Ding Gao‐Ming , Liu Bi‐Zheng , Liu Yan‐Bing , Yu Ping
Published: April 2021

In this study, we present new field geology, whole‐rock geochemical and S–Pb isotope data for the Chambishi deposit in the Zambia Copperbelt (ZCB), in order to constrain the mineralization process and ore sulphur and metal source. The Lower Roan Subgroup clastic rocks are compositionally similar to the Post‐Archean Australian Shale and have low Chemical Index of Alteration, indicating a felsic and slightly weathered source, which we proposed to be the felsic Lufubu Metamorphic Complex (LMC). The Th, Ti, and Zr elemental features suggest that the Lower Roan Subgroup was deposited in a rift basin of passive margin. The 34S values of early‐stage diagenetic Cu‐Co sulphide (−6.2 to +6.6‰, Vienna Canyon Diablo Troilite [V‐CDT]) from the nodular and layered ores are lower than those of the late‐stage vein‐type hydrothermal Cu–Co sulphides and disseminated molybdenites (3.9–11.9‰, V‐CDT), indicating different sulphur precipitation mechanism in the two mineralization stages. Integrated with previous fluid inclusion studies, we suggest that the sulphur for the diagenetic sulphides was from bacterial reduction of sedimentary anhydrite and seawater sulphates, whereas that for the orogenic‐stage sulphides was from both diagenetic sulphide remobilization and from thermochemical sulphate reduction. The mean 238U/204Pb ratios of the diagenetic‐ and orogenic‐stage sulphides are 10.21 and 10.44, respectively, overlapping with those of the average Lufubu schist (10.38) and the Mufulira granodiorite (10.21), and suggest the LMC as the main ore metal source.
Diagenesis and reservoir classification criteria for Jurassic continental sandstone oil reservoir in the western Ordos Basin, China
Authors: Wei Jiaxin , Chen Shou , Gu Yanping , Zhang Huaibiao , Yin Shuai , Yuan Hui
Published: April 2021

The marginal area of a sedimentary basin is closer to the provenance, so the sand body is generally more developed. For the Western Margin Thrust Belt of the Ordos Basin, the quality of the Jurassic sandstone reservoirs is still less studied. Diagenesis and reservoir evaluation are important research contents and hotspots in sedimentary geology. Therefore, in this paper, the diagenesis and reservoir properties of the Jurassic Yan 6 to Yan 10 members (Yan'an Formation) have been systematically studied based on the latest 3D seismic, well logging, cast thin section, scanning electron microscope and petrophysical property tests in this area. Furthermore, the vertical heterogeneity of petrophysical properties of the Jurassic reservoir has been discussed in detail, and the diagenetic evolution sequence and classification criteria of Jurassic sandstone reservoir have been proposed. The research results show that the lithologies of the Yan 6 to Yan 10 members are mainly lithic quartz sandstone, lithic feldspar sandstone and feldspar lithic sandstone. The pore types of sandstone are mainly intergranular pores, followed by dissolution pores, intercrystalline pores and a few microfractures. There are two high‐value porosity zones in the buried depths of 1,950–2,050 m and 2,150–2,250 m, which are the coupling results of dissolution and palaeo‐overpressure. Based on the comprehensive study of petrology, petrophysical properties and diagenesis, the diagenetic evolution sequence of the Jurassic sandstone was restored and a comprehensive classification standard for the Jurassic sandstone reservoirs is proposed. The Jurassic reservoir in the study area is a structural‐lithological reservoir, which has a unified oil–water interface, the Type I and Type II reservoir areas in the structural high positions are conducive to the large‐scale accumulation of hydrocarbons.
Beyond WEIRD: Associations between socioeconomic status, gender, lifetime stress exposure, and depression in Madagascar
Authors: Foubert Laurent , Noël Yvonnick , Spahr Chandler M. , Slavich George M.
Published: April 2021

Objective

Although research has examined associations between socioeconomic status (SES), gender, and acute and chronic life stressors in depression, most studies have been conducted in Western, educated, industrialized, rich, democratic (WEIRD) populations.

Method

We addressed this issue by interviewing 65 adults (55 women, M
age = 37) living in Madagascar, a typical low‐ and middle‐income country.

Results

As hypothesized, women experienced more life stressors and depressive symptoms, on average, than men, as did those from lower (vs. higher) SES backgrounds. Additionally, lifetime stress exposure was associated with greater symptoms of depression, accounting for 19% of the variability in depressive symptom levels. These effects differed for acute versus chronic and distal versus recent stressors. Finally, stress exposure significantly mediated the relation between SES and gender on depressive symptoms, accounting for 24.0%–70.8% of the SES/gender‐depression association depending on stressor type.

Conclusion

These data extend prior research by describing how social stratification and gender relate to lifetime stress exposure and depressive symptoms in a non‐WEIRD population.
An intact boundary between the tumor and inner hypoechoic layer discriminates T1 lesions among sessile elevated gallbladder cancers
Authors: Toyonaga Haruka , Hayashi Tsuyoshi , Ueki Hidetaro , Chikugo Kouki , Ishii Tatsuya , Nasuno Hiroshi , Kin Toshifumi , Takahashi Kuniyuki , Takada Minoru , Ambo Yoshiyasu , Shinohara Toshiya , Yamazaki Hajime , Katanuma Akio
Published: April 2021

Background

The depth of invasion determines the surgical method for treating gallbladder cancer (GBC). However, the preoperative correct diagnosis of invasion depth, especially discrimination of T1 lesions among sessile elevated GBCs, is difficult. We investigated the utility of preoperative endoscopic ultrasound (EUS) findings for diagnosing the invasion depth.

Methods

We studied a sessile elevated GBC specimen diagnosed as a T1 lesion before developing our study protocol. EUS evidenced an intact boundary between the tumor and the inner hypoechoic layer (the intact boundary sign). To evaluate the potential of using this sign to diagnose T1 GBC as a primary outcome indicator, we retrospectively analyzed patients who underwent surgical resection of sessile elevated GBCs between April 2009 and March 2020.

Results

Of the 26 surgically resected sessile elevated GBC specimens, 20 were included and six were excluded due to difficulty in evaluating the overall tumor or layer structure. The Kappa coefficient for interobserver agreement regarding the intact boundary sign was 0.733. The sensitivity and specificity of the sign for diagnosing T1 lesions were 0.857 and 1.000, respectively.

Conclusion

This new EUS finding could guide the accurate diagnosis of T1 lesions in patients with sessile elevated GBC.
A Social Ecological Framework: Counselors' Role in Improving Student Athletes' Help‐Seeking Behaviors
Authors: Reich Aviry L. , Milroy Jeffrey J. , Wyrick David L. , Hebard Stephen P.
Published: April 2021

Student athletes' demands increase their risk for experiencing mental health concerns (Ryan et al., 2018). Risk factors for student athletes include coping with athletic success and failure; balancing dual roles; dealing with identity confusion; and experiencing isolation, injury, career termination, and burnout (Beauchemin, 2012; G. T. Brown, 2014). Using the social ecological model, we review factors that interfere with student athletes' help‐seeking behaviors and propose recommendations for the ways counselors can address these barriers in the roles of educator, advocate, and therapist.
Association between early enteral nutrition and clinical outcome in patients with severe acute heart failure who require invasive mechanical ventilation
Authors: Saijo Takeshi , Yasumoto Koji , Ohashi Makoto , Momoki Chika , Habu Daiki
Published: April 2021

Background

This study aimed to examine the association between early enteral nutrition (EEN) and clinical outcome in patients with severe acute heart failure (AHF).

Methods

This retrospective observational study enrolled consecutive patients with AHF who required continuous invasive mechanical ventilation (IMV) for >48 h and were admitted to a single‐center cardiac care unit (CCU). The primary outcome was CCU length of stay (LoS). We compared patients who were initiated on EN within 48 h of intubation (EEN group) with those who were initiated on EN after 49 h of intubation (delayed EN [DEN] group). Multivariate logistic regression analysis was performed to determine independent factors for primary and secondary outcomes. CCU LoS and IMV time were categorized using the median.

Results

We included 86 patients with AHF (EEN group, n = 56; DEN group, n = 30) who met the inclusion criteria. The median CCU LoS was significantly shorter in the EEN group (10 [8–15] days) than in the DEN group (15 [12–26] days, P = .007). Multivariate analysis indicated that time to EN initiation was an independent factor for CCU LoS (odds ratio [OR], 8.39; 95% confidence interval [CI], 2.18–32.20; P = .002), IMV time (OR, 4.84; 95% CI, 1.37–17.20; P = .015), and incidence of infection (OR, 2.73; 95％ CI, 1.04–7.18; P = .042).

Conclusion

EEN (within 48 h of intubation) for patients with severe AHF who require continuous IMV might be associated with reduced CCU LoS, IMV time, and incidence of infection.
Amino acid δ13C and δ15N analyses reveal distinct species‐specific patterns of trophic plasticity in a marine symbiosis
Authors: Wall Christopher B. , Wallsgrove Natalie J. , Gates Ruth D. , Popp Brian N.
Published: April 2021

Compound‐specific isotope analyses (CSIA) and multivariate “isotope fingerprinting” track biosynthetic sources and reveal trophic interactions in food webs. However, CSIA have not been widely applied in the study of marine symbioses. Here, we exposed a reef coral (Montipora capitata) in symbiosis with Symbiodiniaceae algae to experimental treatments (autotrophy, mixotrophy, heterotrophy) to test for trophic shifts and amino acid (AA) sources using paired bulk (δ13C, δ15N) and AA‐CSIA (δ13CAA, δ15NAA). Treatments did not influence carbon or nitrogen trophic proxies, thereby not supporting nutritional plasticity. Instead, hosts and symbionts consistently overlapped in essential‐ and nonessential‐δ13CAA (11 of 13 amino acids) and trophic‐ and source‐δ15NAA values (9 of 13 amino acids). Host and symbiont trophic‐δ15NAA values positively correlated with a plankton end‐member, indicative of trophic connections and dietary sources for trophic‐AA nitrogen. However, mass balance of AA‐trophic positions (TPGlx–Phe) revealed heterotrophic influences to be highly variable (1–41% heterotrophy). Linear discriminant analysis using M. capitata mean‐normalized essential‐δ13CAA with previously published values (Pocillopora meandrina) showed similar nutrition isotope fingerprints (Symbiodiniaceae vs. plankton) but revealed species‐specific trophic strategies. Montipora capitata and Symbiodiniaceae shared identical AA‐fingerprints, whereas P. meandrina was assigned to either symbiont or plankton nutrition. Thus, M. capitata was 100% reliant on symbionts for essential‐δ13CAA and demonstrated autotrophic fidelity and contrasts with trophic plasticity reported in P. meandrina. While M. capitata AA may originate from host and/or symbiont biosynthesis, AA carbon is Symbiodiniaceae‐derived. Together, AA‐CSIA/isotope fingerprinting advances the study of coral trophic plasticity and are powerful tools in the study of marine symbioses.
Basic Tips: How Do I Start Programming Deep Brain Stimulation in Parkinson Disease Patients?
Authors: Gorodetsky Carolina , Fasano Alfonso
Published: April 2021

Deep brain stimulation (DBS) has become an integral component of Parkinson disease treatment. Programming a DBS device is a time‐consuming process and requires a highly trained specialist to obtain optimal results. During the last few years, we have witnessed a rapid technological advance of DBS systems, making the programming process even more complex and emphasizing the need for a structured approach. In this manuscript and the attached videos, we will demonstrate a step‐by‐step programming approach for DBS targeting the subthalamus and the globus pallidus pars Interna. In doing so we will show the main features and differences of the three main systems available on the market, including the newest ones able to record braingenerated local field potentials for clinical applications.
Genetic and clinical spectrums in Korean Charcot‐Marie‐Tooth disease patients with myelin protein zero mutations
Authors: Kim Hye Jin , Nam Soo Hyun , Kwon Hye Mi , Lim Si On , Park Jae Hong , Kim Hyun Su , Kim Sang Beom , Lee Kyung Suk , Lee Ji Eun , Choi Byung‐Ok , Chung Ki Wha
Published: April 2021

Background

Charcot‐Marie‐Tooth disease (CMT) is the most common disorder of inherited peripheral neuropathies characterized by distal muscle weakness and sensory loss. CMT is usually classified into three types, demyelinating, axonal, and intermediate neuropathies. Mutations in myelin protein zero (MPZ) gene which encodes a transmembrane protein of the Schwann cells as a major component of peripheral myelin have been reported to cause various type of CMT.

Methods

This study screened MPZ mutations in Korean CMT patients (1,121 families) by whole exome sequencing and targeted sequencing.

Results

We identified 22 pathogenic or likely pathogenic MPZ mutations in 36 families as the underlying cause of the CMT1B, CMTDID, or CMT2I subtypes. Among them, five mutations were novel. The frequency of CMT patients with the MPZ mutations was similar or slightly lower compared to other ethnic groups.

Conclusions

We showed that the median onset ages and clinical phenotypes varied by subtypes: the most severe in the CMT1B group, and the mildest in the CMT2I group. This study also observed a clear correlation that earlier onsets cause more severe symptoms. We believe that this study will provide useful reference data for genetic and clinical information on CMT patients with MPZ mutations in Korea.
Application of novel fractional derivative to heat and mass transfer analysis for the slippage flow of viscous fluid with single‐wall carbon nanotube subject to Newtonian heating
Authors: Ahmad Mushtaq , Asjad Muhammad Imran , Singh Jagdev
Published: April 2021

The single‐walled carbon nanotubes are the solid tiny materials in nature with efficient thermal conductivity and has many useful applications in biological domain specifically in the formation of biological nanofluid. The physical effects of single‐wall carbon nanotube (SWCNT) are considered in this study for free convection slippage flow of fractional viscous fluid by considering the thermal radiation, heat generation, chemical reaction of order first, and Newtonian heating through a porous medium. The fractional flow model of viscous fluid with SWCNT is constructed by inserting most recent approach of non‐integer derivative (constant proportional Caputo fractional derivative). Non‐dimensional boundary layer equations which govern the flow are solved analytically via integral transform, namely, the Laplace transform, and explicit transformed results for field variables, temperature, concentration, and velocity are established. Thermal and mass fluxes are also obtained numerically and presented in tabular form. The parametric study is carried out by plotting some graphs of thermal, concentration, and momentum profiles. In the light of paramedic study, it is noted that from the plots of field variables with slip condition are higher than that with the no‐slip condition. The constant proportional Caputo (CPC) fractional derivative is a best choice to get more stable temperature, concentration, and velocity fields than that of ordinary fields. More precisely, fractional parameter controls the boundary thickness of temperature, concentration, and velocity fields.
Integrability of systems of ordinary differential equations via Lie point symmetries
Authors: Al‐Kindi Fatma , Mahomed Fazal M. , Ziad Muhammad
Published: April 2021

The existing literature discusses different strategies to solve a scalar ordinary differential equation using Lie point symmetries. We focus on three of these strategies in order to frame methods for finding solutions of nonlinear systems of ordinary differential equations. These include Lie's integration theorem, method of successive reduction of order, and the method of using the invariants of the admitted symmetry generators. Illustrative examples and those taken from mechanics are presented to highlight the use of these methods.
Industrial control protocols in the Internet core: Dismantling operational practices
Authors: Nawrocki Marcin , Schmidt Thomas C. , Wählisch Matthias
Published: April 2021

Industrial control systems (ICS) are managed remotely with the help of dedicated protocols that were originally designed to work in walled gardens. Many of these protocols have been adapted to Internet transport and support wide‐area communication. ICS now exchange insecure traffic on an inter‐domain level, putting at risk not only common critical infrastructure but also the Internet ecosystem (e.g., by DRDoS attacks). In this paper, we measure and analyze inter‐domain ICS traffic at two central Internet vantage points, an IXP and an ISP. These traffic observations are correlated with data from honeypots and Internet‐wide scans to separate industrial from non‐industrial ICS traffic. We uncover mainly unprotected inter‐domain ICS traffic and provide an in‐depth view on Internet‐wide ICS communication. Our results can be used (i) to create precise filters for potentially harmful non‐industrial ICS traffic and (ii) to detect ICS sending unprotected inter‐domain ICS traffic, being vulnerable to eavesdropping and traffic manipulation attacks. Additionally, we survey recent security extensions of ICS protocols, of which we find very little deployment. We estimate an upper bound of the deployment status for ICS security protocols in the Internet core.
Catalytic and structural properties of ATP‐dependent caprolactamase from Pseudomonas jessenii
Authors: Marjanovic Antonija , Rozeboom Henriëtte J. , de Vries Meintje S. , Mayer Clemens , Otzen Marleen , Wijma Hein J. , Janssen Dick B.
Published: April 2021

Caprolactamase is the first enzyme in the caprolactam degradation pathway of Pseudomonas jessenii. It is composed of two subunits (CapA and CapB) and sequence‐related to other ATP‐dependent enzymes involved in lactam hydrolysis, like 5‐oxoprolinases and hydantoinases. Low sequence similarity also exists with ATP‐dependent acetone‐ and acetophenone carboxylases. The caprolactamase was produced in Escherichia coli, isolated by His‐tag affinity chromatography, and subjected to functional and structural studies. Activity toward caprolactam required ATP and was dependent on the presence of bicarbonate in the assay buffer. The hydrolysis product was identified as 6‐aminocaproic acid. Quantum mechanical modeling indicated that the hydrolysis of caprolactam was highly disfavored (ΔG0'= 23 kJ/mol), which explained the ATP dependence. A crystal structure showed that the enzyme exists as an (αβ)2 tetramer and revealed an ATP‐binding site in CapA and a Zn‐coordinating site in CapB. Mutations in the ATP‐binding site of CapA (D11A and D295A) significantly reduced product formation. Mutants with substitutions in the metal binding site of CapB (D41A, H99A, D101A, and H124A) were inactive and less thermostable than the wild‐type enzyme. These residues proved to be essential for activity and on basis of the experimental findings we propose possible mechanisms for ATP‐dependent lactam hydrolysis.
Buckling on Fe‐Doped AlGaN/GaN High Electron Mobility Transistor Films after Laser Liftoff Process: Phenomena and Mechanism
Authors: Hu Haoyue , Xiao Hongling , Guo Fen , Wang Quan , Feng Chun , Jiang Lijuan , Wang Qian , Liu Hongxin , Wang Xiaoliang
Published: April 2021

The influence of Fe in the buffer layer on the laser liftoff (LLO) of GaN high electron mobility transistors is presented herein. LLO is performed on Fe‐doped GaN films using a KrF excimer LLO system. The morphology, crystal characteristics, and 2D electron gas (2DEG) characteristics of the GaN films after LLO are characterized using a 3D optical microscope, X‐ray diffraction, and Hall methods. The present work is different from previous methods because of the large‐area buckling instead of cracks on the Fe‐doped GaN films. The results show that the crystal quality and 2DEG characteristics of the buckled parts are significantly affected. Furthermore, a modified simulation model of the temperature and thermal‐induced stress fields in the films is used to explain the buckling of the films, whose results are consistent with the characterization results. The additional absorption centers induced by the Fe impurity energy levels increase the gradient of temperature field, thereby increasing the compressive stresses in the films at the edges of the laser spots. Moreover, a higher temperature is observed at the interface between the film and the bonding glue, which results in the debonding. Therefore, Fe‐doped GaN films are more prone to buckling than unintentionally doped GaN films.