bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractSpontaneous 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

AbstractN‐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

AbstractLittle‐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

AbstractPhenotypic 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.
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

AbstractMultiple 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

SummaryHealthcare 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.
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

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

AbstractBackgroundThe 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.MethodsWe 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.ResultsOf 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.ConclusionThis new EUS finding could guide the accurate diagnosis of T1 lesions in patients with sessile elevated GBC.
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

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

AbstractCompound‐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

ABSTRACTDeep 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

AbstractBackgroundCharcot‐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.MethodsThis study screened MPZ mutations in Korean CMT patients (1,121 families) by whole exome sequencing and targeted sequencing.ResultsWe 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.ConclusionsWe 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.
Industrial control protocols in the Internet core: Dismantling operational practices
Authors: Nawrocki Marcin , Schmidt Thomas C. , Wählisch Matthias 
Published: April 2021

SummaryIndustrial 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

AbstractCaprolactamase 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.
The role of shallow convection in the momentum budget of the trades from large‐eddy‐simulation hindcasts
Authors: Helfer Kevin C. , Nuijens Louise , Dixit Vishal V. 
Published: April 2021

AbstractMotivated by the abundance of low clouds in the subtropics, where the easterly trade winds prevail, we study the role of shallow convection in the momentum budget of the trades. To this end, we use ICON‐LEM hindcasts run over the North Atlantic for 12 days corresponding to the NARVAL1 (winter) and NARVAL2 (summer) flight campaigns. The simulation protocol consists of several nested domains, and we focus on the inner domains (≈100 × 100 km2) which have been run at resolutions of 150–600 m and are forced by analysis data, thus exhibiting realistic conditions. Combined, the resolved advection and the subgrid stresses decelerate the easterly flow over a frictional layer that balances the prevailing geostrophic wind forcing. Irrespective of the horizontal resolution, this layer is about 2 km deep in the strong winter trades and 1 km in summer, as winds and geostrophic forcing weaken and cloudiness reduces. The unresolved processes are strongest near the surface and are well captured by traditional K‐diffusion theory, but convective‐scale motions which are not considered in K‐diffusion theory contribute the most in the upper part of the mixed layer and are strongest just below cloud base. The results point out that convection in the mixed layer – the roots of trade‐wind cumuli and subcloud‐layer circulations – play an important role in slowing down easterly flow below cloud base (but little in the cloud layer itself), which helps make the zonal wind jet more distinct. Most of the friction within the clouds and near the wind jet stems from smaller‐scale turbulence stresses.
Generating Discorrelated States for Quantum Information Protocols by Coherent Multimode Photon Addition
Authors: Biagi Nicola , Costanzo Luca S. , Bellini Marco , Zavatta Alessandro 
Published: April 2021

AbstractIt is demonstrated that the recently developed technique of delocalized single photon addition may generate discorrelation, a new joint statistical property of multimode quantum light states, whereby the number of photons in each mode can take any value individually, but two modes together never exhibit the same. By coherently adding a single photon to two identical coherent states of light in different temporal modes, the first experimental observation of discorrelation is provided. The capability of manipulating this statistical property has applications in scenarios involving the secure distribution of information among untrusted parties, like in the so‐called “mental poker” games.