bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nickel(II)‐Mediated C−S Cross‐Coupling Between Thiols and ortho‐Substituted Arylboronic Acid
Authors: Hanaya Kengo , Ohtsu Hiroyoshi , Kawano Masaki , Higashibayashi Shuhei , Sugai Takeshi 
Published: December 2020

AbstractHerein, we report a C−S cross‐coupling reaction between alkyl thiols or aryl thiols and ortho‐substituted arylboronic acids that proceeds in the presence of an inexpensive and ligand‐free NiCl2 ⋅ 6H2O salt and N‐methylmorpholine, a weak base, at 25 °C in air. The presence of coordinating and electron‐withdrawing groups at the ortho‐position of the arylboronic acids played a crucial role in determining the efficiency of the reaction. X‐ray crystallographic analysis revealed that the [NiCl2(DMF)2(H2O)2] complex was formed in‐situ. The complex is an excellent precursor of the active nickel species. The reaction offers an extremely mild and operationally convenient method to access a wide variety of alkyl aryl sulfides and diaryl sulfides without using expensive transition metals, such as palladium, gold, and rhodium, and specialized and expensive ligands.
Castor Epoxy Fatty Acid Alkyl Ester Estolides as Bioplasticizers for Poly(Vinyl Chloride)
Authors: Stolp Lucas J. , Grass Michael , Kodali Dharma R. 
Published: December 2020

AbstractEpoxy fatty acid alkyl ester estolides were synthesized from castor oil to be used as biobased plasticizers for poly(vinyl chloride) (PVC) as a safer replacement for phthalate plasticizers. Initially, castor oil was transesterified with methanol or n‐butanol to quantitatively yield castor fatty acid alkyl esters. Acetylation of hydroxyl function with acetic anhydride led to the formation of estolide. The unsaturation was epoxidized, resulting in a bifunctional epoxy fatty acid alkyl ester estolide. The bioplasticizers were compounded with PVC and were evaluated for their functionality and compared with commercial phthalate plasticizer diisononyl phthalate (DINP) and nonphthalate 1,2‐cyclohexanoic acid diisononyl ester (DINCH). The bioplasticizers showed excellent gelation, efficiency, and compatibility, as well as plastisol viscosity and thermal properties, comparable to or better than the plastisols prepared with commercial controls DINP and DINCH. The volatility of the methyl ester was inferior to the butyl ester. Both compounds showed low water resistance properties. Further evaluation of the butyl ester under tropical conditions of high temperature and humidity confirmed limited compatibility. This indicates that the castor epoxy fatty acid ester estolides would be better suited for applications that do not come in contact with water for prolonged periods, such as flooring, artificial leather, wiring, or wall coverings.
Development of non‐leaching antibacterial coatings through quaternary ammonium salts of styrene based copolymers
Authors: Ifra  , Kongkham Bhani , Sharma Shivangi , Chaurasiya Alok , Biswal Agni K. , Hariprasad P. , Saha Sampa 
Published: December 2020

AbstractNon‐leaching antibacterial coatings through quaternary ammonium salts containing polymers were successfully produced in a facile way to provide infection resistant surfaces against multi drug resistant bacteria such as B. licheniformis. In order to do so, a series of random copolymers of styrene (S) and vinyl benzyl chloride (VBC) were synthesized by free radical polymerization technique and subsequently, VBC (V) was functionalized with N,N‐dimethylhexadecylamine to introduce quaternary ammonium (QA) salts in the backbone of the copolymers. The copolymers showed an excellent film forming ability, thereby providing an ultrathin coating on various substrates such as metal (stainless steel), glass, polyethylene and polystyrene, as observed by SEM.The coatings were found to be uniform, non leachable in aqueous medium and exhibit good adhesion to various substrates. The antibacterial and antibiofilm activity of the non‐leachable coating of random copolymers were screened against B. licheniformis. Among, the copolymer containing 75% quaternized VBC (75VSQA) having 16‐C long alkyl chain was found to show maximum antibacterial and antibiofilm activity owing to an appropriate hydrophobic /hydrophilic balance. Their non‐leachable antibacterial and antibiofim activity make these coatings suitable for many applications, e.g. marine paints, textile/hospital coatings etc.
All‐trans retinoic acid induces leukemia resistance to NK cell cytotoxicity by down‐regulating B7‐H6 expression via c‐Myc signaling
Authors: Cao Guoshuai , Cheng Ying , Zheng Xiaodong , Wei Haiming , Tian Zhigang , Sun Rui , Sun Haoyu 
Published: January 2021

AbstractBackgroundThe interaction between activating receptor NKp30 and its major tumor ligand B7‐H6 is important for NK cell‐mediated tumor rejection. However, the regulation of B7‐H6 by tumor therapeutics remains largely unknown. In this study, we investigated the regulation of B7‐H6 by all‐trans retinoic acid (atRA), a terminal differentiation inducer of tumor cells that is extensively used for clinical leukemia therapy.MethodsWe investigated the role of NKp30:B7‐H6 axis in NK cell‐mediated tumor lysis against leukemia cells and the influence of atRA treatment on the cytotoxicity of NK cells using NK cell lines (NK92 and NKG) and leukemia cell lines (U‐937 and THP‐1). We evaluated the effect of atRA treatment on the expression of B7‐H6 using real‐time PCR, flow cytometry and western blotting. We used CRISPR/Cas9 to knockdown B7‐H6 expression and siRNA to knockdown c‐Myc in U‐937 cells to evaluate the role of B7‐H6 and c‐Myc in atRA‐induced tumor resistance against NK cells.ResultsNK cell‐mediated U‐937 cell lysis was mainly dependent on NKp30/B7‐H6 interaction. Blockade of B7‐H6 by monoclonal antibody significantly impaired NK cytotoxicity. atRA treatment induced U‐937 resistance to NK cell cytotoxicity by reducing B7‐H6 expression, and showed no effect on NK cytotoxicity against B7‐H6 knockdown U‐937 cells. Epigenetic modifications, such as DNA methylation and histone deacetylase (HDAC), were not responsible for atRA‐mediated B7‐H6 down‐regulation as inhibitors of these pathways could not restore B7‐H6 mRNA expression. On the other hand, atRA treatment reduced c‐Myc expression, which in turn inhibited the transcription of B7‐H6 on leukemia cells.ConclusionatRA treatment promotes tumor cell resistance against NK cell‐mediated lysis by down‐regulating B7‐H6 expression via the c‐Myc signaling pathway, suggesting that more attention needs to be paid to the immunological adverse effects in the clinical use of atRA treatment.
Genetic structure as a response to anthropogenic and extreme weather disturbances of a coastal dune dwelling spider, Arctosa sanctaerosae
Authors: Hataway Robert A. , Reed David H. 
Published: December 2020

AbstractThe continued increase in the number of tourists visiting the Northern Gulf Coast (NGC), USA, in the last century, and the resulting sprawl of large cities along the coast, has degraded and fragmented the available habitat of Arctosa sanctaerosae, a wolf spider endemic to the secondary dunes of the white sandy beaches of the NGC. In addition to anthropogenic disturbance to this coastal region, hurricanes are an additional and natural perturbation to the ecosystem. The data presented here explore the status of populations of this species spanning the entire known range and the factors influencing population demography including anthropogenic disturbance and severe tropical storms. Using microsatellite markers, we were able to document the genetic structure of A. sanctaerosae, including current and historic patterns of migration. These results combined with ecological and census data reveal the characteristics that have influenced population persistence: ecological variables affecting the recovery of the population clusters after severe tropical storms, genetic fragmentation due to anthropogenic disturbance, and their interaction. These findings demonstrate the significance that the high traffic beach communities of the NGC and their impact on the once intact contiguous dune ecosystem have on recovery after severe tropical storms. Contemporary modeling methods that compare current and historic levels of gene flow suggest A. sanctaerosae has experienced a single, contiguous population subdivision, and the isolates reduced in size since the onset of commercial development of the NGC. These results point to the need for monitoring of the species and increased protection for this endangered habitat.
Assessment of Corrosion Inhibition Performance and Adsorption Thermodynamics of Hydrogen Phosphate (HPO42−) and Molybdate (MoO42−) Oxyanions on Tin in Maleic Acid
Authors: Ait Addi Brahim , El Ibrahimi Brahim , Ait Addi Abdelaziz , Shaban Abdul , Ait Addi El‐Habib , Hamdani Mohamed 
Published: January 2021

AbstractThe influence of hydrogen phosphate (HPO42−) and molybdate ions (MoO42−) on the behavior of tin corrosion in 0.2 M maleic acid was compared using experimental and theoretical techniques. The experimental studies consisted of the electrochemical investigations (potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS)), along with the surface analytical techniques (SEM and EDX). Additionally, the theoretical analysis (the chemical quantum computations at MP4/SDD level of theory in the aqueous phase), was conducted. The experimental outcomes illustrated that the inhibition efficiency (η%) increases with the concentration of the inhibitors, reaching 88 % and 81 % at 2×10−2 M concentration of MoO42− and HPO42−, respectively. The potentiodynamic polarization curves revealed that HPO42− performance is a cathodic‐type inhibitor, while MoO42− shows a mixed‐type behavior. The increase in temperature decreased the η% values of both inhibitors. Based on surface analysis and thermodynamic study, the presence of the two inhibitors formed protective films on the tin surface through a physisorption mechanism. The chemical quantum computations using the complete fourth‐order Møller Plesset perturbation theory (MP4 with SDD basis) method results outlined the favorable affinity of the investigated inorganic inhibitors to interact with the tin surface, which interprets the well‐observed inhibition efficiencies.
Benzodiazepines and antidepressants: Effects on cognitive and functional decline in Alzheimer's disease and Lewy body dementia
Authors: Borda Miguel Germán , Jaramillo‐Jimenez Alberto , Oesterhus Ragnhild , Santacruz Jose Manuel , Tovar‐Rios Diego Alejandro , Soennesyn Hogne , Cano‐Gutierrez Carlos Alberto , Vik‐Mo Audun Osland , Aarsland Dag 
Published: January 2021

AbstractObjectivesWe aim to study the effects of the prescription of benzodiazepines and antidepressants on cognitive and functional decline in older adults living with Alzheimer's disease (AD) and Lewy body dementia (LBD) over a 5‐year follow‐up.MethodsThis is a longitudinal analysis of a Norwegian cohort study entitled “The Dementia Study of Western Norway” (DemVest). We included 196 patients newly diagnosed with AD (n = 111) and LBD (n = 85), followed annually for 5 years. Three prescription groups were defined: only benzodiazepines (BZD), only antidepressants (ADep), and the combination of benzodiazepines and antidepressants (BZD‐ADep). Linear mixed‐effects models were conducted to analyze the effect of the defined groups on the outcomes. The outcomes were functional decline, measured by the Rapid Disability Rating Scale—2, and cognition measured with the Mini‐Mental State Examination.ResultsPrescription of the combination of benzodiazepines and antidepressants in LBD was associated with faster functional decline. In AD, the prescription of BZD and BZD‐ADep was associated with greater functional deterioration. ADep alone did not show positive or negative significant associations with the studied outcomes.ConclusionsBZD and especially the combination of BZD and ADep are associated with functional decline in AD and LBD and should be used cautiously.
Exploratory study of functional and psychological factors associated with employment status in patients with head and neck cancer
Authors: Broemer Laura , Friedrich Michael , Wichmann Gunnar , Müller Juliane , Neumuth Thomas , Dietz Andreas , Mehnert Anja , Wiegand Susanne , Zebralla Veit 
Published: January 2021

AbstractBackgroundCompared with other malignancies, head and neck cancer (HNC) increases the risk of not returning to work (RTW).MethodsWithin a cross‐sectional study, patients with HNC filled out the OncoFunction questionnaire, a version of the International Classification of Functioning Core Sets for HNC. In 231 patients below 65 years of age, associations of sociodemographic, clinical, functional, and psychological factors with employment and participation in rehabilitation program were explored.ResultsUnemployed patients reported more swallowing difficulties and speaking problems. Being unemployed was associated with higher levels of depressive and anxiety symptoms, fatigue, and lower global health. Rehabilitation participation was not significantly associated with any of the assessed factors except for smoking.ConclusionsUnemployed patients with HNC are more burdened than employed patients with HNC regarding clinical, psychological, and functional factors. These differences are more evident later in recovery. Rehabilitation participation was not associated with psychological and functional burden which indicates the need for tailored HNC rehabilitation programs.
Prostate cancer extracellular vesicles mediate intercellular communication with bone marrow cells and promote metastasis in a cholesterol‐dependent manner
Authors: Henrich Stephen E. , McMahon Kaylin M. , Plebanek Michael P. , Calvert Andrea E. , Feliciano Timothy J. , Parrish Samuel , Tavora Fabio , Mega Anthony , De Souza Andre , Carneiro Benedito A. , Thaxton C. Shad 
Published: January 2021

AbstractPrimary tumours can establish long‐range communication with distant
organs to transform them into fertile soil for circulating tumour cells to
implant and proliferate, a process called pre‐metastatic niche (PMN) formation. Tumour‐derived extracellular vesicles (EV) are potent mediators of PMN formation due to their diverse complement of pro‐malignant molecular cargo and their propensity to target specific cell types (Costa‐Silva et al., 2015; Hoshino et al., 2015; Peinado et al., 2012; Peinado et al., 2017). While significant progress has been made to understand the mechanisms by which pro‐metastatic EVs create tumour‐favouring microenvironments at pre‐metastatic organ sites, comparatively little attention has been paid to the factors intrinsic to recipient cells that may modify the extent to which pro‐metastatic EV signalling is received and transduced. Here, we investigated the role of recipient cell cholesterol homeostasis in prostate cancer (PCa) EV‐mediated signalling and metastasis. Using a bone metastatic model of enzalutamide‐resistant PCa, we first characterized an axis of EV‐mediated communication between PCa cells and bone marrow that is marked by in vitro and in vivo PCa EV uptake by bone marrow myeloid cells, activation of NF‐κB signalling, enhanced osteoclast differentiation, and reduced myeloid thrombospondin‐1 expression. We then employed a targeted, biomimetic approach to reduce myeloid cell cholesterol in vitro and in vivo prior to conditioning with PCa EVs. Reducing myeloid cell cholesterol prevented the uptake of PCa EVs by recipient myeloid cells, abolished NF‐κB activity and osteoclast differentiation, stabilized thrombospondin‐1 expression, and reduced metastatic burden by 77%. These results demonstrate that cholesterol homeostasis in bone marrow myeloid cells regulates pro‐metastatic EV signalling and metastasis by acting as a gatekeeper for EV signal transduction.
Red‐tailed phascogales: A review of their biology and importance as model marsupial species
Authors: Old Julie M. , Ong Oselyne T. W. , Stannard Hayley J. 
Published: December 2020

AbstractThere are many limitations when using traditional laboratory species. Limits on variation, may result in limited outcomes, at both the species and individual level, due to different individuals/species having diverse physiological processes, or differing molecular and genetic mechanisms. By using a variety of model species, we will be able to develop creative solutions to biological problems and identify differences of which we were not previously aware. The laboratory mouse has been a suitable model species for various mammalian studies, however most are bred specifically for laboratory research with limited variability due to selective breeding. Marsupial models offer unique research opportunities compared to eutherian models. We believe that there should be an expansion in marsupial model species, and the introduction of the red‐tailed phascogale (Phascogale calura), a dasyurid marsupial, should be one of them. Phascogales are easily managed in captivity, and there are now multiple studies involving their development, reproduction, nutrition, behavior and immune system, which can serve as a baseline for future studies. The addition of the phascogale as a model species will improve future mammalian studies by introducing variability and offer alternate solutions to biological problems, particularly in the areas of genetics, nutrition, immunology, the neuro‐endocrine system, and ageing, due to their semelparous reproductive strategy and hence, subsequent predictive physiology. In this review, we provide information based on existing research on red‐tailed phascogales to support their inclusion as a model species.
Secondary kinetic deuterium isotope effects on unimolecular cleavage reactions: Zero‐point vibrational energy and qualitative RRKM theory
Authors: Østergaard Lars F. , Hammerum Steen 
Published: January 2021

AbstractSecondary kinetic isotope effects arise as the result of transition‐state zero‐point vibrational energy differences. Unimolecular simple cleavage reactions of gas‐phase ions in mass spectrometers allow detailed studies of isotope effects on competing reactions, particularly when examined in intramolecular competition experiments where interpretation requires very few simplifying assumptions. The zero‐point energy differences reflect changes of isotope sensitive vibrational properties, and both α‐ and β‐secondary deuterium isotope effects are related to the sp
3 → sp
2 hybridization changes that accompany bond cleavage. Deuterium substitution three bonds or more removed from the bond broken also gives rise to isotope effects, but their origin is less easily interpreted. The magnitude and variation of the observed effects depend not only on zero‐point energy differences; a number of additional factors play a role. The influence of the critical energy, the excess energy, the size of the reactant, and the presence of competing reactions can be rationalized within a simple, qualitative RRKM framework. The distinction between kinetic and thermodynamic isotope effects is not always obvious.
Kinetics of MMA Atom Transfer Radical Polymerization Initiated by Reducing Agent in Stirred Batch Emulsion Reactor
Authors: Awad Mohammed , Dhib Ramdhane , Duever Thomas 
Published: December 2020

AbstractAb initio emulsion atom transfer radical polymerization (ATRP) differs from regular emulsion polymerization because the kinetic and thermodynamic aspects of each process are very unlikely alike. This paper presents a kinetic analysis of activator generated by electron transfer (AGET) ATRP of methyl methacrylate (MMA) in a stirred emulsion reactor. The focus of the study is to assess the variation of the monomer content in the organic phase and the rate polymerization for different reaction temperatures, as well as the impact of surfactant content and stirring speed on latex stability. Poly(methyl methacrylate) (PMMA) polymer samples are analyzed by means of gravimetry, dynamic light scattering, gel permeation chromatography, and HNMR techniques to determine monomer conversion, polymer particle diameter, molecular weight distribution, and polymer molecular structure, respectively. The results show the production of PMMA of narrow polydispersity index (Ð) and low molar mass (Mn) for MMA conversion around 60% and detect two‐regions instead of a three‐regions trend of rate of polymerization (Rp) as conventional emulsion polymerization. The reaction rate increases during the nucleation stage and then flattens over an invariant trend which confirms a living feature of the AGET ATRP polymerization. The average number of radicals per latex particle (ñ) is also debated.
Tagungen und Corona:Quer‐ statt Hochformat
Authors: van Wickeren Stefan , Kösters Kristina , Zhou Zhimin , Ying Bixian 
Published: January 2021

AbstractAus „Electrochemistry“ wurde in diesem Jahr „Electrochemistry Undercover“, eine aufgrund der Covid‐19‐Pandemie vollständig digitalisierte Konferenz. Wie eine Postersession dabei funktionieren könnte, haben Mitarbeitende des Meet‐Batterieforschungszentrums in Münster überlegt und umgesetzt. Ihre Erfahrungen liefern Ideen für den wissenschaftlichen Austausch auf Distanz.
Fünftes Doktorandenseminar Nucleinsäurechemie in Bad Herrenalb
Authors: Richert Clemens 
Published: January 2021

AbstractAnfang Oktober fand das Doktorandenseminar der Deutschen Nucleinsäurechemiegemeinschaft (DNG) in Bad Herrenalb statt. An der zweitägigen Veranstaltung nahmen 25 Forscher teil. Es gab sieben Doktorandenvorträge, sieben Posterpräsentationen und sechs Dozentenvorträge, zwei davon per Videoübertragung. Das Spektrum der Vorträge reichte von einer Einführung in die Vortragstechnik bis zu Biologie und Synthese von Nucleinsäuren.
Laborprozesse und Legoroboter
Authors: von der Esch Elisabeth 
Published: January 2021

AbstractDie chemische Industrie automatisiert die Abläufe in ihren Laboren. Und auch in der Forschung kann Automatisierung die Arbeit erleichtern. Wie das geht, lehrt das Chemiestudium bisher jedoch kaum. An der TU München lernen Studierende nun, Pipettier‐, Sortier‐ oder Transportierroboter zu entwerfen sowie Daten automatisiert auszuwerten. Unter Pandemiebedingungen funktioniert die Lehrveranstaltung auch auf Distanz.
Mortality in sickle cell disease: A population‐based study in an aboriginal community in the Gudalur Valley, Nilgiris, Tamil Nadu, India
Authors: Sheshadri Veena , Shabeer Pathayakandi , Santhirapala Vatshalan , Jayaram Anusha , Krishnamurti Lakshmanan , Menon Nandakumar 
Published: December 2020

AbstractBackgroundSickle cell disease (SCD), the most common monogenic disorder, affects more than 300 000 births annually, with 44 000 in India. Although the clinical phenotype of SCD is considered to be milder in aboriginal populations in India, there is a paucity of data on outcomes. To determine the severity of SCD in this population, we studied mortality rates and causes of mortality in a longitudinal cohort of patients with SCD in a remote aboriginal community in India receiving community‐based comprehensive care.ProceduresCauses of death were analyzed in this cohort from January 2008 to December 2018. Details were collected from hospital records and in case of deaths at home by utilizing the WHO verbal autopsy questionnaire.ResultsThe cohort consisted of 157 patients belonging to the Paniya, Betta Kurumba, Kattunyakan, and Mullu Kurumba tribes. During the study period, there were 22 deaths, all from the Paniya tribe. Twelve deaths (54.5%) occurred in the hospital and the remaining at home (45.5%), reflecting a crude mortality rate of 140 per 1000 population. Twenty‐five percent of deaths occurred in the 6–18 age group. There were no deaths in the 0–5 age group. The median age of death was 25 years, which was 30 years less than in the non‐SCD aboriginal population. The leading causes of death were acute chest syndrome, anemia, and sepsis among the SCD patients and stroke and suicides in the non‐SCD aboriginal population.ConclusionSCD is a severe disease among the Gudalur Valley's aboriginal population with a significant risk of premature mortality.