bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Oxidative Transformations During the Biosynthesis of Terrein and Related Natural Products
Authors: Kahlert Lukas , Bernardi Darlon , Hauser Maurice , Ióca Laura P. , Berlinck Roberto G. S. , Skellam Elizabeth J. , Cox Russell J.
Published: June 2021

The mycotoxin terrein is derived from the C10‐precursor 6‐hydroxymellein (6‐HM) via an oxidative ring contraction. Although the corresponding biosynthetic gene cluster (BGC) has been identified, details of the enzymatic oxidative transformations are lacking. Combining heterologous expression and in vitro studies we show that the flavin‐dependent monooxygenase (FMO) TerC catalyzes the initial oxidative decarboxylation of 6‐HM. The reactive intermediate is further hydroxylated by the second FMO TerD to yield a highly oxygenated aromatic species, but further reconstitution of the pathway was hampered. A related BGC was identified in the marine‐derived Roussoella sp. DLM33 and confirmed by heterologous expression. These studies demonstrate that the biosynthetic pathways of terrein and related (polychlorinated) congeners diverge after oxidative decarboxylation of the lactone precursor that is catalyzed by a conserved FMO and further indicate that early dehydration of the side chain is an essential step.
Enhancement of kinetic rates of CO2 in aqueous solutions of piperazine and methyldiethanolamine with addition of sulfolane
Authors: Ahmed Abdelmouiz , Henni Amr , Guibadj Abdenacer , Hadjadj Ahmed
Published: June 2021

Measurements of kinetics rates of CO2 in aqueous solutions of methyldiethanolamine (MDEA), piperazine (PZ), and mixtures of (MDEA + PZ), (PZ + sulfolane) and (MDEA + sulfolane) were carried out using the stopped flow technique, and reported in terms of pseudo‐first‐order rate constants (k0). When possible, the second‐order reaction rate constants (k2) were regressed from the data. Experiments were performed over new concentration ranges of (10–60), (200–800), (200–800, 10–40), (10–40, 10–200), and (200–800, 10–200) mol/m3 for the above‐mentioned five systems, respectively, and at temperatures varying from (298.15–313.15 K). When sulfolane was added to the amine solution, pseudo‐first‐order rate constants in the mixed solvents were higher than in aqueous MDEA and PZ solutions at all temperatures. The kinetic rates were highest at 298.15 K and decreased at higher temperatures for aqueous (MDEA + sulfolane) solutions but increased with temperature for aqueous (PZ + sulfolane) systems. Reaction orders for both PZ and MDEA were practically one at all sulfolane concentrations and temperatures. The base catalysis mechanism was used to regress very well data for aqueous MDEA and (MDEA + sulfolane + water) and the termolecular mechanism was used for (PZ + sulfolane + water) system. Both the zwitterion and termolecular models were able to fit the experimental data for the aqueous PZ system well. Finally, the termolecular and a hybrid model based on the combination of the Zwitterion and base catalysis mechanisms were able to successfully correlate the experimental data for the mixed aqueous (MDEA + PZ) systems.
Cancer matters: Now more than ever!
Authors: Ramalingam Suresh S.
Published: June 2021

Cancer, among the oldest and most prestigious oncology journals, is well positioned to bring the best of science to the broadest audience with a strong focus on featuring research that directly affects the lives of patients with cancer.
Computational modelling of the scoliotic spine: A literature review
Authors: Gould Samuele L. , Cristofolini Luca , Davico Giorgio , Viceconti Marco
Published: June 2021

Scoliosis is a deformity of the spine that in severe cases requires surgical treatment. There is still disagreement among clinicians as to what the aim of such treatment is as well as the optimal surgical technique. Numerical models can aid clinical decision‐making by estimating the outcome of a given surgical intervention. This paper provided some background information on the modelling of the healthy spine and a review of the literature on scoliotic spine models, their validation, and their application. An overview of the methods and techniques used to construct scoliotic finite element and multibody models was given as well as the boundary conditions used in the simulations. The current limitations of the models were discussed as well as how such limitations are addressed in non‐scoliotic spine models. Finally, future directions for the numerical modelling of scoliosis were addressed.
Estimating heritability in honeybees: Comparison of three major methods based on empirical and simulated datasets
Authors: Jourdan‐Pineau Hélène , Antoine Gaëlle , Galataud Julien , Delatte Hélène , Simiand Christophe , Clémencet Johanna
Published: June 2021

The genetic contribution to phenotypic variation (namely the heritability) affects the response to selection. In honeybee, the haplodiploid sex determination does not allow the straightforward use of classical quantitative genetics methods to estimate heritability and genetic correlation. Nevertheless, specific methods have been developed for about 40 years. In particular, sibling analyses are frequently used with three main methods: an historical model using the average colony relatedness, a half‐sib/full‐sib model, and the more recent animal model. We compared those three methods using experimental and simulated datasets to see which performs the best. Our experimental dataset is composed of 10 colonies with a total sample of 853 workers. All individuals were genotyped to reconstitute the pedigree, and phenotypic traits were measured: labial palpus and wing cubital veins lengths. We also simulated phenotypic datasets with varying levels of heritability, common environment effect, and genetic correlation between traits. The simulation approach showed that the average colony relatedness was highly biased in presence of common environment effect whereas the half‐sib/full‐sib and the animal model gave reliable estimates of heritability. The animal model provided the greatest precision in genetic correlations. Using this latter method, we found that wing vein lengths had high heritabilities whereas the palpus length had lower heritability due to larger environmental variance and/or measurement error. Finally, significant genetic correlations among measured traits indicate that they do not evolve independently.
Cooking small and large portions of “biodiversity‐soup”: Miniaturized DNA metabarcoding PCRs perform as good as large‐volume PCRs
Authors: Buchner Dominik , Beermann Arne J. , Leese Florian , Weiss Martina
Published: June 2021

DNA metabarcoding is a powerful tool to assess arthropod diversity in environmental bulk samples such as Malaise trap, pitfall trap, or hand net samples. While comparative performance tests for different extraction protocols, primers, and Taq polymerases have been made, the effect of different PCR volumes on bulk sample metabarcoding performance is less explored. Although using small PCR volumes reduces overall costs, they may lead to decreased taxon recovery or higher replicate variability due to increased pipetting imprecision, PCR stochasticity (PCR drift), or inhibition when using high amounts of template community DNA. We here performed a simple DNA metabarcoding experiment to test if species detection and the consistency of technical replicates decrease with decreasing PCR volume in standard reaction tubes. We used a mock community sample consisting of different amounts of DNA from 35 arthropod species, and a Malaise trap sample composed of many thousand insect specimens. PCR volumes tested were 5, 10, 15, 20, 25, and 50 µl. Both samples were replicated 14 times in the first PCR step with two technical replicates each in the second PCR step. Our data show that small PCR volumes did neither have systematically lower species detection or richness values, nor lower consistency between PCR replicates. We therefore recommend low volumes primarily depending on handling constraints. Further, we emphasize the importance of sequencing depth for taxon recovery.
Behaviors associated with vocal communication of squirrels
Authors: Diggins Corinne A.
Published: June 2021

Vocal communication is an important method squirrels (Sciuridae) use to transfer information from one individual to others. While behaviors associated with vocal communication have been explored in individual species or single call‐types in specific groups of squirrels, no comprehensive review of these behaviors exists for Sciuridae. Herein, I review the current literature to describe behaviors associated with vocal communication in three groups of squirrels: ground squirrels, tree squirrels, and flying squirrels. I discuss the behavioral functions of squirrel vocalizations. A wide variety of behaviors are associated with particular call‐types produced by squirrels, including alarm, agonistic, discomfort, affiliative, mating, and neonatal calls. There are large knowledge gaps in cataloging the vocal repertoires and associated behaviors of many species of squirrels, including commonly studied species such as marmots and ground squirrels, as alarm calls are typically focused on and other call‐types are understudied or ignored. Since vocal communication is important to the development, reproduction, and survival of squirrels, further understanding the biological and ecological drivers behind vocal repertoires is critical to evaluating the ethology of this family as a whole.
Asymmetry of marine invasions across tropical oceans
Authors: Torchin Mark E. , Freestone Amy L. , McCann Linda , Larson Kristen , SchlÖder Carmen , Steves Brian P. , Fofonoff Paul , Repetto Michele F. , Ruiz Gregory M.
Published: June 2021

Understanding the mechanisms of spatial variation of biological invasions, across local‐to‐global scales, has been a major challenge. The importance of evolutionary history for invasion dynamics was noted by Darwin, and several studies have since considered how biodiversity of source and recipient regions can influence the probability of invasions. For over a century, the Panama Canal has connected water bodies and biotas with different evolutionary histories, and created a global shipping hot spot, providing unique opportunities to test mechanisms that affect invasion patterns. Here, we test for asymmetry in both the extent of invasions and predation effects, a possible mechanism of biotic resistance, between two tropical oceans at similar latitudes. We estimated nonnative species (NNS) richness for sessile marine invertebrates, using standardized field surveys and literature synthesis, to examine whether invasions are asymmetrical, with more NNS present in the less diverse Pacific compared to the Atlantic. We also experimentally tested whether predation differentially limits the abundance and distribution of these invertebrates between oceans. In standardized surveys, observed total NNS richness was higher in the Pacific (18 NNS, 30% of all Pacific species) than the Atlantic (11 NNS, 13% of all Atlantic species). Similarly, literature‐based records also display this asymmetry between coasts. When considering only the reciprocal exchange of NNS between Atlantic and Pacific biotas, NNS exchange from Atlantic to Pacific was eightfold higher than the opposite direction, exceeding the asymmetry predicted by random exchange based simply on differences of overall diversity per region. Predation substantially reduced biomass and changed NNS composition in the Pacific, but no such effects were detected on the Atlantic coast. Specifically, some dominant NNS were particularly susceptible to predation in the Pacific, supporting the hypothesis that predation may reduce the abundance of certain NNS here. These results are consistent with predictions that high diversity in source regions, and species interactions in recipient regions, shape marine invasion patterns. Our comparisons and experiments across two tropical ocean basins, suggest that global invasion dynamics are likely driven by both ecological and evolutionary factors that shape susceptibility to and directionality of invasions across biogeographic scales.
Selective Formation of Lotus Leaf‐ and Donut‐Like Gold Nanoplates via Seeded Growth
Authors: Zhang Gongguo , Ma Yanyun , Zhao Wenjun , Zheng Yiqun
Published: June 2021

We report a seeded growth of gold (Au) nanoplates with two distinct morphologies, which are similar to a lotus leaf and a donut, respectively. The success of this synthesis relies on the use of flat Au nanoplates in high purity as seeds, followed by a controlled deposition. In particular, the presence of Ag+ led to the deposition of Au atoms preferentially occurred at the central part of one face of the nanoplate and thus the formation of lotus leaf‐like shape. In contrast, when Ag+ was absent, the growth mainly occurred to the edge region. Then, cold‐welding of newly‐formed branches and further diffusion of Au atoms created holes in the nanoplate, resulting in the formation of donut‐like shape. The Au nano‐lotus leaves with tunable sizes exhibited absorbance in near‐infrared region and enhanced chemical activities in electrochemical measurements. The current strategy is extended to fabricate Au−Ag nanoplates with a similar lotus leaf‐like morphology, which also exhibited strong absorbance in near‐infrared region in UV‐vis extinction spectra. The current work allows the fabrication of two‐dimensional Au‐based nanomaterials with concave shape and three‐dimensional architecture and could be potentially extended to other noble metals and alloys.
Highly Ordered, Self‐Assembled Monolayers of a Spin‐Crossover Complex with In‐Plane Interactions
Authors: Zheng Sipeng , Spa Silvia , van Geest Erik P. , van Ruitenbeek Jan M. , Bonnet Sylvestre
Published: June 2021

For the technological integration of molecular switches in electronic devices, self‐assembling nanomaterials of such switches are highly sought after. The syntheses of a new tetrapyridyl ligand bearing a C12 alkyl chain and two N−H bridges (compound 1) and of its iron(II) complex [Fe(1)(NCS)2] (compound 2), are described. Magnetic susceptibility data for bulk samples of 2 confirmed their gradual spin‐crossover properties. The self‐assembly of 1 and 2 on highly ordered pyrolytic graphite surfaces (HOPG) was investigated by Scanning Tunneling Microscopy (STM). Both compounds 1 and 2 formed ordered monolayers after deposition by drop casting. The patterns of the two compounds are very different, which is attributed to the fundamentally different hydrogen bonding networks before and after coordination of Fe(NCS)2 to the tetradentate chelate. Two possible models for the self‐assembly of 1 and 2 are provided. This work suggests that it is possible to design molecular switches that self‐assemble on surfaces in highly ordered monolayer films. This is a significant step in the development of spin‐switching materials, which may streamline the integration of molecular switches in for example memory and sensing devices.
Spin Crossover vs. High‐Spin Iron(II) Complexes in N4S2Coordination Sphere Containing Picolyl‐Thioether Ligands and NCE (E=S, Se and BH3) Co‐Ligands
Authors: Plaza‐Lozano Diego , Conde‐Gallardo Agustín , Olguín Juan
Published: June 2021

To study the effect of the chelate ring size on the magnetic properties of thioether‐based iron(II) metal complexes, two ligands have been envisaged, synthesised and characterised. The two ligands correspond to the bidentate benzylpicolylthioether (PySBn) and tetradentate 2,3‐bis(((2‐pyridylmethyl)thio)methyl)quinoxaline (QuinoxS). Five iron(II) complexes have been synthesised, containing either two bidentate ligands or one tetradentate ligand, and two N‐bond NCE co‐ligands (E=S, Se or BH3):trans‐[FeII(PySBn)2(NCE)2] (1 a–b) andcis‐[FeII(QuinoxS)(NCE)2] (2 a–c),afor E=S,bfor E=Se andcfor E=BH3. The iron(II) complexes have been characterised by standard techniques, X‐ray crystallography (except for complex1 a) and VT‐magnetic measurements in the solid state. X‐ray crystallography showed that all the complexes are isolated in the high spin (HS) state, based on the relatively long Fe−L bond lengths, Fe−N>2.0 Å and Fe−S≈2.5–2.6 Å. VT‐magnetic measurements demonstrated that complexes1 aand2 a‐care stabilised in the HS‐state, showing orbital contribution togand zero field splitting. However, complexes1 bshows a relatively abrupt, hysteretic, and incomplete at the low‐end spin conversion, with T1/2↓=92, T1/2↑=98 K and ΔT1/2=6 K at 5 K min−1, moreover, the hysteresis loop is scan rate dependent increasing up to 11 K at 10 K min−1. An analysis of structural and electronic parameters has been performed to rationalise the differing magnetic properties of the metal complexes, such as metallacycle size, bond lengths and angles, andcis‐vs. trans‐coordination mode. A comparison with the literature‐reported spin crossover iron(II) complexes in N4S2coordination sphere containing NCE co‐ligands has been conducted as well, finding that, as previously reported, the Fe−N−C(E) bond angle is diagnostic for determining the spin lability of the metal complexes, and in addition we have found that the N−C(E) bond length is too useful.
Rh(III)‐Catalyzed [4+2] Cyclization of 2‐Aryl‐1H‐benzo[d]imidazoles with Maleimides via C‐H Activation
Authors: Deng Chen , Li Changchang , Yao Jinzhong , Jin Quanli , Miao Maozhong , Zhou Hongwei
Published: June 2021

A rhodium‐catalyzed formal [4+2]‐cyclization of 2‐aryl‐1H‐benzo[d]imidazoles with maleimides through C−H bond activation process is described here. Such an approach enables selectively construct a series of functionalizedcis‐dihydro‐benzimidazo[2,1‐a]isoquinolines. The reaction features a broad substrate scope with respect to both coupling components, and the desired products were obtained with up to 85 % yields.
Separation and purification of plant terpenoids from biotransformation
Authors: Chen Linhao , Pang Yaru , Luo Yan , Cheng Xu , Lv Bo , Li Chun
Published: June 2021

The production of plant terpenoids through biotransformation has undoubtedly become one of the research hotspots, and the continuous upgrading of the corresponding downstream technology is also particularly important. Downstream technology is the indispensable technical channel for the industrialization of plant terpenoids. How to efficiently separate high‐purity products from complex microbial fermentation broths or enzyme‐catalyzed reactions to achieve high separation rates, high returns and environmental friendliness has become the focus of research in recent years. This review mainly introduces the common separation methods of plant terpenoids based on biotransformation from the perspectives of engineering strain construction, unit separation technology, product properties and added value. Then, further attention was paid to the application prospects of intelligent cell factories and control in the separation of plant terpenoids. Finally, some current challenges and prospects are proposed, which provide possible directions and guidance for the separation and purification of terpenoids and even industrialization.
Efficacy of minute virus of mice (MVM) inactivation utilizing high temperature short time (HTST) pasteurization and suitability assessment of pasteurized, concentrated glucose feeds in Chinese hamster ovary (CHO) cell expression systems
Authors: Gemmell David K. , Mack Aaron , Wegmann Sabrina , Han David , Tuccelli Ronald , Johnson Matthew , Miller Corinne
Published: June 2021

There is a growing need to provide effective adventitious agent mitigation for high risk upstream cell culture raw materials used for the production of biologics. It is also highly important in the growing fields of cell and gene therapies. Glucose is a critical raw material necessary for effective cell growth and productivity; however, glucose is the highest risk animal‐origin‐free raw material for viral contamination, and often the highest risk raw material in the upstream process as more companies move to chemically defined media. This study examines the efficacy of utilizing High Temperature Short Time (HTST) pasteurization for inactivation of physiochemically resistant, worst‐case parvovirus using a bench‐scale HTST system. We demonstrated approximately six log inactivation of Minute Virus of Mice (MVM) in concentrated glucose feeds without impacting the subsequent performance of the glucose in a Chinese Hamster Ovary (CHO) expression system.
Hydrothermal synthesis of nano spheroid‐like ZnMn2O4 materials as high‐performance anodes for lithium‐ion batteries
Authors: Li Pengwei , Luo Shao‐hua , Wang Qing , Zhang Yahui , Liu Xin , Xu Caihong , Liang Jinsheng , Duan Xinhui
Published: June 2021

Spent zinc‐manganese batteries contain valuable elements, especially Zn and Mn, and recycling these metal elements can realize the sustainable development of resources. In this paper, a novel process of preparing ZnMn2O4 as anode material for lithium‐ion batteries from the spent zinc‐manganese battery is present. Nano ZnMn2O4 is synthesized by the low‐temperature hydrothermal method, and the formation mechanism is discussed. The structure, morphology, and composition of the products are characterized by XRD and SEM. The result shows that ZnMn2O4 with a crystal size of about 50 nm is prepared under the conditions of T = 200°C, pH = 7, reaction time t = 3 days, and n(Zn: Mn) = 0.966:2, which have the advantages of good crystallinity and high purity. The nanocrystallization and spheroid‐like structure of ZnMn2O4 determine that the battery assembled with ZnMn2O4 has a high initial discharge capacity, and the initial discharge specific capacity reaches 902.5 mAh g−1 at 0.1 A g−1. This study shows that the nano ZnMn2O4 synthesized by the hydrothermal method is a promising anode material for lithium‐ion batteries.
Modeling and analysis of priority and range‐based‐deterministic and synchronous multichannel extension‐guaranteed time slot allocation in IEEE 802.15.4e medium access control protocol
Authors: Asuti Manjunath G. , Basarkod Prabhugoud I.
Published: June 2021

Internet of Things (IoT) enabled technology in the current applications such as smart grids, smart cities, and smart health sectors utilize wireless sensor networks (WSN) to establish stable and reliable communication between the nodes. Moreover, the primary requirement of WSN in IoT applications is to provide low‐rate data communication. The IEEE 802.15.4e standard‐based medium access control (MAC) protocol is found suitable for low‐rate data communication in WSN. The IEEE 802.15.4e standard adopts a deterministic and synchronous multichannel extension (DSME) MAC protocol which employs a multisuperframe structure with multichannel data transmission during the contention free period. However, the guaranteed time slot (GTS) allocation process in DSME employed by the standard may not be suitable for an adaptive traffic network scenario that has a direct impact on the throughput and bandwidth utilization. In this article, we develop a priority and range‐based DSME‐GTS allocation algorithm based on the priorities of end nodes and range estimation. Furthermore, the proposed algorithm is developed for the two types of network scenarios encountered in a star topology‐enabled WSN. In scenario‐1, the slots allocation process is carried out based on the priorities of end nodes. Next, in scenario‐2, the slots allocation process is carried out based on the range estimation of end nodes. Detailed mathematical modeling of the proposed methodology is provided for the various performance metrics. The model is validated using the MATLAB 2017a programming tool. Simulation results show that the proposed methodology outperforms the existing DSME‐GTS approaches in terms of performance metrics such as packet delivery ratio, end‐to‐end delay, packet loss ratio, throughput, delay, bandwidth utilization, and the energy consumption.
A survey of new orientations in the field of vehicular cybersecurity, applying artificial intelligence based methods
Authors: Pethő Zsombor , Török Árpád , Szalay Zsolt
Published: June 2021

Nowadays, cybersecurity is an emerging research area in the automotive industry, and it is investigated by many different perspectives. Our article is a review of existing vehicular security solutions that covers the state‐of‐the‐art and future research directions. This article is a new contribution to tutorials/surveys related to the vehicular cybersecurity domain with the latest details. We developed a database from 140 articles from the field of automotive security. In the database, we assigned specific attributes to every article (such as Web of Science Impact Factor or the number of citations). The data set was analyzed by the K‐means clustering and decision tree analysis methods to identify and characterize the generated groups of papers. Following this, the article highlights the research areas that might receive more attention in the future. Accordingly, the result of the current research can be applied by the decision‐makers, researchers, and Original Equipment Manufacturers to allocate additional resources to those domains, which is expected to shape the future of vehicular security.
Identity Wind Tunneling: A method for discovering an organization’s strategic identity using scenarios
Authors: Fergnani Alessandro , Sweeney John A.
Published: June 2021

In a turbulent environment characterized by unexpected events, such as the COVID‐19 pandemic, a sharp oil price decline, and dramatic economic crises, many organizations face not only challenges but also an “identity crisis” as they are unable to respond to the question "who are we as an organization?" Some organizations may concurrently hold multiple identities without being clear on whether these are shared and agreed upon, and on their role in potentially disruptive futures. In response to this challenge and addressing a methodological gap in the broader futures and foresight field, we draw on both futures and foresight as well as management and organization literature to propose a new organizational foresight method: Identity Wind Tunneling (IWT). Designed as an enhancement of wind tunneling approaches, IWT allows an organization to understand, test, and manage multiple organizational identities. Furthermore, IWT facilitates the alignment of organizational identities across a range of possible futures created during a scenario planning process with the ultimate goal of finding astrategic identity. This represents the central, enduring, and distinctive role that the organization embodies while pursuing a long‐term and holistic strategic direction that is robust across all scenarios. The strategic identity either clarifies or reimagines the identity of the organization. The paper provides a step‐by‐step explanation of how to implement IWT and ​presents a case study of its application. The method is also presented with a series of open‐source templates created on the whiteboard collaborative platform Miro (https://miro.com/app/board/o9J_kqakYjs=/).
Facile synthesis and electrocatalytic performance for oxygen reduction of boron‐doped carbon catalysts on graphene sheets
Authors: Suo Ni , Huang Hao , Wang Xi , Hou Xiaoduo , Shao Zhigang , Zhang Guifeng
Published: June 2021

Boron‐doped carbon catalysts are synthesized via a liquid‐phase electrodeposition technique using methanol‐containing graphene nucleating agent and B2O3 dopant as the reaction solution. The relationship between boron‐doped content and specific surface area (SSA), as well as their influence on electrocatalytic activity for oxygen reduction reaction, is studied by changing the concentration of B2O3. When the concentrations of B2O3 are 23.94 and 14.36 mol ml–1, respectively, boron‐doped content and SSA reach the peak values of 0.53 at.% and 18.476 m2 g–1. The data of electrochemical tests, such as onset potential of –0.016 V and transferred electron number of 3.74–3.77 in the range of –0.5 to –0.9 V, exhibit that the catalyst with a boron‐doped content of 0.47 at.% and an SSA of 18.476 m2 g–1 has the best electrocatalytic activity in all the synthesized samples. The enhanced electrocatalytic activity is ascribed to a synergistic effect originating from boron‐doped content and SSA, in which the SSA contributes more. The experimental results have important guiding significance to maximize the oxygen reduction activity of catalysts and elucidate that it tends to design and synthesize catalysts with large SSA compared with doping.
Innovative TBM transport logistics in construction section H33 of Brenner Base Tunnel
Authors: Morocutti Alex , Lussu Andrea , Leitner Edgar , Kaiser Christian , Ertl Anton , Grüllich Sebastian
Published: June 2021

The Tulfes‐Pfons construction section of the Brenner Base Tunnel includes a 16.6 km long tunnel section excavated with an open gripper TBM. Due to the very difficult logistic conditions (steep access tunnel with 10 % gradient and a 90° bend at the transition to the exploratory tunnel as well as a limited clearance profile with 8 m diameter), the contractor and client decided on an alternative supply of the TBM – the ’multi‐service vehicle' (MSV). This laser‐controlled train on rubber wheels without rails is able to handle both the steep access and the 90° bend. After 16 km of excavated tunnel with a top performance of 61 m/d and top monthly performance of up to 800 m in hard rock conditions with 1000 m overburden, the decision to use the MSV has proved to be a complete success. In addition to the logistics and safety advantages, a cost reduction has also been achieved compared to the planned conventional system. MSV are a cost‐effective and technically proven alternative to conventional track‐bound TBM supply equipment.
Regulation of microglia population dynamics throughout development, health, and disease
Authors: Hammond Brady P. , Manek Rupali , Kerr Bradley J. , Macauley Matthew S. , Plemel Jason R.
Published: June 2021

The dynamic expansions and contractions of the microglia population in the central nervous system (CNS) to achieve homeostasis are likely vital for their function. Microglia respond to injury or disease but also help guide neurodevelopment, modulate neural circuitry throughout life, and direct regeneration. Throughout these processes, microglia density changes, as does the volume of area that each microglia surveys. Given that microglia are responsible for sensing subtle alterations to their environment, a change in their density could affect their capacity to mobilize rapidly. In this review, we attempt to synthesize the current literature on the ligands and conditions that promote microglial proliferation across development, adulthood, and neurodegenerative conditions. Microglia display an impressive proliferative capacity during development and in neurodegenerative diseases that is almost completely absent at homeostasis. However, the appropriate function of microglia in each state is critically dependent on density fluctuations that are primarily induced by proliferation. Proliferation is a natural microglial response to insult and often serves neuroprotective functions. In contrast, inappropriate microglial proliferation, whether too much or too little, often precipitates undesirable consequences for nervous system health. Thus, fluctuations in the microglia population are tightly regulated to ensure these immune cells can execute their diverse functions.
Weather, mental health, and mobility during the first wave of the COVID‐19 pandemic
Authors: Burdett Ashley , Davillas Apostolos , Etheridge Ben
Published: June 2021

During the first United Kingdom wave of the COVID‐19 outbreak, the first lockdown was announced on March 23, 2020, with a final easing of the restrictions on July 4, 2020. Among the most important public health costs of lockdown restrictions are the potential adverse effects on mental health and physical activity. Using data from the UK Household Longitudinal Study and Google COVID‐19 Mobility Reports we find evidence of reduced park mobility during the initial period of the first UK lockdown and confirm existing evidence of worsening mental health. Linkage with weather data shows that contrary to popular belief, daily or weekly weather conditions do not exacerbate the mental health consequences of the pandemic, as we found no systematic associations during the first lockdown period; on the other hand, we find systematic links between park mobility and weather over the same period.
A rare case of primary small cell neuroendocrine carcinoma of the Bartholin gland
Authors: Han Ling , Zheng Ai , Chen YaLi
Published: June 2021

Synopsis

Primary small cell neuroendocrine carcinoma of the Bartholin gland is an extremely rare event with no treatment consensus. The present study reports a case of Bartholin gland carcinoma.
Dependence of laser‐induced optical breakdown on skin type during 1064 nm picosecond laser treatment
Authors: Kim Hyeonsoo , Hwang Jewan Kaiser , Choi Jongman , Kang Hyun Wook
Published: June 2021

The current study aims to evaluate the dependence of laser‐induced optical breakdown (LIOB) on skin types by using 1064 nm picosecond laser with micro‐lens arrays (MLA) and diffractive optical elements (DOE). Both black and white skin tissues were examined to comparatively assess the LIOB effects in the skin in terms of laser‐induced vacuolization. The black skin irradiated at 3.0 J/cm2 demonstrated that MLA yielded a deeper distribution (180‐400 μm) of laser‐induced vacuoles with a size of 67 μm, compared to DOE (180‐280 μm; 40 μm in size). However, the white skin presented that MLA created larger vacuoles (134 μm in size) in a smaller number at deeper distributions (125‐700 μm) than MLA with the black skin. DOE generated no laser‐induced vacuolization in the white skin. The white skin tissue with inherent higher scattering could be responsible for deeper vacuolization after the picosecond laser treatment. Further investigations are expected to determine the optimal treatment conditions for various skin types.
An analysis of valence electronic structure from a viewpoint of resonance theory: Tautomerization of formamide and diazadiboretidine
Authors: Nakatani Kaho , Higashi Masahiro , Fukuda Ryoichi , Sato Hirofumi
Published: June 2021

The resonance theory is still very useful in understanding the valence electron structure. However, such a viewpoint is not usually obtained by general‐purpose quantum chemical calculations, instead requires rather special treatment such as valence bond methods. In this study, we propose a method based on second quantization to analyze the results obtained by general‐purpose quantum chemical calculations from the local point of view of electronic structure and analyze diazadiboretidine and the tautomerization of formamide. This method requires only the “PS”‐matrix, consisting of the density matrix (P‐matrix) and overlap matrix, and can be computed with a comparable load to that of Mulliken population analysis. A key feature of the method is that, unlike other methods proposed so far, it makes direct use of the results of general‐purpose quantum chemical calculations.
Unhappiness and casual attributions of homelessness among people living homeless in León (Nicaragua)
Authors: Vázquez José Juan , Berríos Alberto
Published: June 2021

Nicaragua is one of the countries with the lowest levels of development in Latin America, with a collectivist culture, where information on people in a homeless situation is very limited. The study examines a sample of people living homeless in the city of León (Nicaragua), their level of overall happiness, their future expectations, their perception of the evolution of their situation, their causal attributions of homelessness, and the aspects they believe are most important for overcoming their situation. Forty‐one of the 68 homeless people contacted in León (Nicaragua) responded to a structured interview. The results show that the interviewees reported very low levels of overall happiness, although their future expectations were positive. The interviewees attributed homelessness situation (their own and other people's) primarily to individualistic causes and problems in family relationships, and they had a tendency to consider both themselves and other people living homeless responsible for their homelessness. The results are compared to the data obtained using similar methodologies and instruments for people living homeless in Madrid (Spain) and trash pickers in León (Nicaragua)—two groups in situations of extreme poverty and social exclusion.
Better to Decide Together: Shared Consumer Decision Making, Perceived Power, and Relationship Satisfaction
Authors: Brick Danielle J. , Zhou Lingrui , Chartrand Tanya L. , Fitzsimons Gavan J.
Published: June 2021

Shared consumer decisions, particularly those made with a relationship partner, can be very different from decisions that are made alone. Across multiple studies, we investigate how shared consumer decision making affects perceptions of power and relationship satisfaction. We integrate two streams of research to create a novel theory about consumer decision making and perceived power. Specifically, we suggest that shared consumer decision making combines two necessary components of power—an individual's influence over and a partner's engagement in the decision—and that these combined components drive power perceptions. In other words, individuals who relinquish some control and make a decision with their partner, ironically, perceive having greater power than if they had made the decision alone. We further find that shared decision making and greater perceived power lead to greater satisfaction with the relationship in which the decisions are made. By focusing on consumer decision making within relationships, the current research contributes to the literatures on decision making, social influences in consumer behavior, close relationships, consumer well‐being, and power.
Reevaluating the prognostic value of RAS mutation status in patients with resected liver metastases from colorectal cancer: A systematic review and meta‐analysis
Authors: Pikoulis Emmanouil , Papaconstantinou Dimitrios , Pikouli Anastasia , Wang Jane , Theodoridis Charalampos , Margonis Georgios Antonios
Published: June 2021

Background

Although the value of Rat Sarcoma Oncogene (RAS) mutation status in predicting long‐term outcomes in patients with colorectal liver metastases (CRLM) is widely accepted, the magnitude of its impact has recently been challenged by three large cohort studies. The aim of this meta‐analysis is to reevaluate the impact of RAS mutations on overall survival (OS) and disease‐free survival (DFS) in patients who underwent curative‐intent resection of CRLM.

Methods

A comprehensive literature search was performed for studies reporting outcomes of patients undergoing curative‐intent surgery stratified by RAS mutation status. Exclusion criteria were defined a priori. Subgroup analysis was performed to evaluate the effect of publication date, sample size, and KRAS vs any RAS mutation on overall outcomes.

Results

Ten studies incorporating 3115 patients with known RAS status were identified. Pooled results revealed significantly worse OS (Hazard Ratio 1.5, 95% CI 1.31‐1.71) and DFS (Hazard Ratio 1.36, 95% CI 1.22‐1.52) in RAS‐mutated patients. Subgroup analyses revealed that studies including more than 300 patients or published after 2015 reported lower HR than their counterparts.

Conclusion

The results of this meta‐analysis suggest that the prognostic value of RAS mutation status in patients with CRLM has been previously overestimated.
Accelerated numerical modeling of RF circuits using network characteristic mode analysis
Authors: Li Hongliang , Jin Jian‐Ming , Hajiaboli Amir , Jachowski Douglas R.
Published: June 2021

A fast numerical modeling approach based on network characteristic mode analysis (CMA) is presented and investigated for analyzing electrical layouts in miniature RF filters, such as surface acoustic wave filters. In this approach, a generalized eigenvalue decomposition is performed on the Z‐parameters of an electrical layout at one or two sampling frequencies that can be computed and extracted with any numerical full‐wave method. The obtained eigenvalues are used to extract modal resistance, inductance, and capacitance matrices for each eigenmode. The frequency dependence of the modal resistance matrix can be assumed a priori or determined automatically, and the modal inductance and capacitance matrices are assumed frequency independent. These modal matrices are then used to approximate the Z‐parameters at any other frequencies to provide the response of the electrical layout, which can then be combined with the frequency responses of other components, such as resonators, to yield the electrical response of an entire RF filter. Compared with the previously developed analytic extension of eigenvalues, this fast CMA‐based method is less affected by the frequency variation of eigenmodes since the frequency dependences of the eigenmodes are implicitly canceled out in its formulation. The accuracy of this approach is evaluated by comparing with results from full‐wave analyses. For RF circuits whose electrical sizes are small and whose frequency range of interest is relatively small, the proposed CMA‐based fast frequency sweep approach is found to be sufficiently accurate and highly practical for engineering applications.
Precipitation efficiency of cloud and its influencing factors over the Tibetan plateau
Authors: Zhao Pengguo , Xiao Hui , Liu Jia , Zhou Yunjun
Published: June 2021

The basic characteristics of cloud water, precipitation, and the dependence of precipitation efficiency (PE) on the influencing factors over the Tibetan Plateau (TP) are investigated. Results found that the liquid water path shows a significant downward trend in winter over the TP, and the ice water path shows a significant upward trend in the pre‐monsoon and winter seasons and a significant downward trend in the monsoon season in the western TP from 1998 to 2015. In the eastern TP, the precipitation in the monsoon season also shows a significant downward trend, which may be related to the weakening of the South Asian monsoon. Results have determined that precipitation depends more on the ice water cloud than on the liquid water cloud over the TP. Moreover, the convective available potential energy (CAPE) and the low‐tropospheric relative humidity (RH) are two environmental factors that have a prominent influence on the PE. During the monsoon season, higher CAPE and RH were conducive to a larger PE over the TP. The results suggest that the CAPE has a positive effect on the PE, which means that the PE is directly dependent on the convective precipitation, mainly due to the frequent convective activity and dominant convective precipitation over the TP.
Analysis of historical heatwaves in the United Kingdom using gridded temperature data
Authors: Beckett Alexander D. , Sanderson Michael G.
Published: June 2021

Areas of land in the United Kingdom (UK) affected by heatwaves between 1960 and 2019 have been analysed using a daily gridded temperature dataset. An new metric, the ‘heatwave cumulative area’, defined as the sum of the largest single area on all days within a given heatwave, was found to be useful for distinguishing extreme heatwaves (those which lasted for many days and affected large parts of the UK) from lesser heatwaves. At the time of writing, the heatwaves of July 1975, August 1990 and July 2019 had the largest areas. Positive trends in numbers, durations and areas of heatwaves were found as a result of rising summer temperatures. The maximum areas and maximum temperatures of the heatwaves were found to be highly correlated. The heatwave of 1976, in many ways, remains the most extreme event to have affected the UK, owing to its large area and long duration with temperatures above 30°C.
In‐syringe ionic liquid‐dispersive liquid–liquid microextraction coupled with HPLC for the determination of trans,trans‐muconic acid in human urine sample
Authors: Abbaszadeh Sepideh , Yousefinejad Saeed , Jafari Saeed , Soleimani Esmaeel
Published: June 2021

trans,trans‐Muconic acid has been widely used as a biomarker in biological monitoring of benzene‐exposed workers during routine occupational health services. In the present study, a novel microextraction technique, in‐syringe ionic liquid‐dispersive liquid–liquid microextraction, was implemented for preconcentration of trans,trans‐muconic acid followed by analytical determination by high‐performance liquid chromatography with ultraviolet detection. Moreover, the important variables affecting the performance of applied microextraction technique including needle diameter, volume of the spiked sample, volume of the ionic liquid, salt addition, rotation speed of centrifugation, centrifuge time, and ultrasonic time were optimized by experimental design. A good linear relationship was observed at the range of 0.032–10 μg/mL between the peak area and the concentration levels (R2 = 0.9997). The limit of detection and extraction recovery for trans,trans‐muconic acid were 0.011 μg/mL and >96.2%, respectively. This method provided easy and rapid analysis of low amounts of trans,trans‐muconic acid in human urine with simple equipment.
Comparative evaluation of a low‐cost solar powered otoscope with a traditional device among health care workers in Malawi
Authors: Balfour Katharine , McCarthy Amy , Hey Shi Ying , Kousha Obaid , Singano Emmanuel , Mulwafu Wakisa , Walker David F. D. L. , Blaikie Andrew
Published: June 2021

Objectives

To comparatively evaluate a low‐cost otoscope with a traditional device among health care workers in Malawi.

Methods

The study is a prospective, comparative, qualitative observational survey of health care worker's opinions using 5‐point Likert rating scales and tick box categories in a 10‐item survey questionnaire. Twenty‐five mixed cadre health care workers from the Ear, Nose, and Throat Department of the Queen Elizabeth Hospital, Blantyre in Malawi were recruited. Outcomes measures used were ease of speculum attachment, handling, insertion, stability, the quality of view, color, build, brightness, overall ease of use, and their suitability for local work.

Results

The low‐cost otoscope scored statistically higher in overall combined performance, as well as in the remaining four out of the nine attributes. Notably, 54.2% of users rated the low‐cost device more suitable than the traditional device for use in low‐middle income countries, 25% were equivocal, and 20.8% preferred the traditional device.

Conclusion

This study found the Arclight otoscope to be an appropriate and practical substitute for more expensive traditional otoscopes for the delivery of ENT services in low resource settings.

Level of Evidence

N/A
Accessing the full spectrum of corrosion behaviour of tempered type 420 stainless steel
Authors: Zhou Yiqi , Engelberg Dirk Lars
Published: June 2021

Bipolar electrochemistry produces a linear potential gradient between two feeder electrodes, providing access to the full spectrum of anodic‐to‐cathodic electrochemical behaviour. A type 420 martensitic stainless steel has been used to investigate microstructure evolution and corrosion behaviour with application of different tempering heat treatments. Tempering treatments at 250°C, 400°C and 700°C revealed the occurrence of pitting corrosion, with treatments at 550°C resulting in general and intergranular corrosion. Cr23C6 was present in all tempering conditions, with Cr7C3 and CrC only observed for tempering at 550°C. The 250°C tempering treatment had the highest corrosion resistance with a hardness value much higher than 500 HV.