bluuebunny/crossref_metadata_2025 huggingface dataset:
Bilateral Ovarian Mature Cystic Teratoma- A Rare Case Presentation
Authors: Akhtar Kafil , Talha Mohd , Alam Saquib , Mohsin Zehra
Published: February 2021

The incidence of bilateral mature cystic teratoma of the ovary is only 10%. Ovarian mature cystic teratomas are common, benign, pelvic tumours and can be easily detected by ultrasonography. Recurrent ovarian teratomas are very rare, and cases of bilateral teratomas are even rarer. So, it is advisable to routinely check the ovary contralaterally during the surgical procedure along with careful pelvic sonographic examination of both the ovaries. Inadvertent extensive surgery should be avoided in this benign condition that might further compromise the fertility of young patients. We report a rare case of bilateral mature cystic teratoma of the ovary in a 28-year-old female, who presented to the gynaecologic outpatient department with complaints of intermittent dull aching, diffuse lower abdominal pain and dysmenorrhea for three months. Transvaginal ultrasonography revealed bilateral complex ovarian masses that raised suspicion of dermoid cysts with hypoechoic endometrial collections. Her Cancer Antigen 125 (CA-125) was normal. A bilateral ovarian cystectomy was performed and histopathology confirmed the diagnosis. This case highlights a rare occurrence of bilateral ovarian mature cystic teratoma, where cystectomy was performed to preserve the fertility in a young female.
Synergistic Anxiolytic Effect of Curcumin and Zinc on Acute and Chronic Models of Anxiety in Mice
Authors: Anandan Isswariya , Selvaraj Nitya , Meenakshi R , Rajamohammad Meher Ali , Anandabaskar Nishanthi , Jayabalan Nalini Devi
Published: February 2021

Introduction: Anxiety disorders being ranked at sixth position in the global burden of diseases is affecting over 250 million people. Curcumin, an active phytochemical flavonoid, has shown to induce the monoamine neurotransmitter serotonin, a prominent neurotransmitter in modulating the brain state in anxiety. Also, evidences reveal that zinc plays a key role in human neurodevelopment and supplementation of zinc enhanced the efficacy of antidepressant drugs through synergistic action. Aim: To evaluate the synergistic antianxiety effect of curcumin and zinc on acute and chronic models of anxiety in male swiss albino mice. Materials and Methods: A total of 36 male Swiss Albino mice, weighing 20-30 g, were randomly grouped to six groups, such that each group consisted of six mice. Group 1 served as control. Group 2 received standard drug diazepam 3 mg/kg Intra Peritoneal (IP). Group 3 and 4 received curcumin at doses of 5 and 10 mg/kg, respectively. Group 5 and 6 received curcumin at doses 5 and 10 mg/kg per oral (p.o) along with zinc chloride 10 mg/kg IP, respectively. The anxiolytic effect was studied in two validated models of anxiety such as Elevated Plus Maze (EPM) test and light/dark box test. Each animal was tested initially in the EPM followed by light/dark box test after administration of drug/vehicle one hour prior to the experiment in acute study. Following a washout period of one week, the animals were utilised for the study of chronic anxiolytic effect wherein the drugs were administered once daily for 14 days. Results: Curcumin at doses of 5 mg/kg and 10 mg/kg with zinc chloride 10 mg/kg showed a significant increase in the number of entries and time spent in open arm in EPM both on acute and chronic administration (p<0.001). In the light/dark box test, curcumin at doses of 5 mg/kg and 10 mg/kg when given along with zinc chloride 10 mg/kg significantly increased the number of entries and time spent in the light compartment both in acute and chronic models (p<0.001). Conclusion: The anxiolytic effect of synergistic action of curcumin and zinc was efficacious in both acute and chronic models of anxiety in mice.
Identification of Non-fermenters by Matrix Assisted Laser Desorption/Ionisation- Time of Flight Mass Spectrometry: Case Series of Achromobacter Infections
Authors: Thosani Pratik , Lall Mahima , Shergill Shelinder Pal Singh , Dhillon Mukesh
Published: February 2021

Achromobacter is a non-fermenting Gram Negative Bacillus (GNB) belonging to the family Alcaligenaceae. It is emerging as a pathogen, causing myriad of infections in different patient groups. Often wrongly identified by conventional microbiological techniques, Achromobacter when recovered from clinical specimens have often been discarded as contaminants. Accurate species identification of the currently known 21 species of Achromobacter, is difficult, labour-intensive and time consuming. Automation has made it possible to reliably and correctly identify Achromobacterspecies and other non-fermenters. Matrix Assisted Laser Desorption Ionisation-Time Of Flight-Mass Spectrometry (MALDI-TOF-MS) is a boon as it rapidly and accurately identifies Achromobacter species in clinical specimens. Three cases of Achromobacter infection, highlighting the pathogenic potential of the bacteria and the role of automation in its identification are presented with due consent from relatives or patient themselves. This case series highlights that Achromobacterwhen recovered from clinical specimens should not be discarded as contaminants especially if isolated repeatedly. Case one was a patient who had developed pyelonephritis and sepsis, associated with bacteraemia and ended fatally, Achromobacter was recovered on two occasions from the blood culture. Case two was a patient who was diagnosed of acute pancreatitis with an infected peripancreatic collection who recovered with prolonged therapy, Achromobacter was repeatedly isolated from the pus draining from the peripancreatic collection. Case three was a patient with an infected malignant ulcer with purulent discharge from the swelling. In all three cases Achromobacter was isolated and identified by MALDI-TOF-MS.
ЗОЛОТАРНИК КАНАДСКИЙ SOLIDAGO CANADENSIS L. В АБХАЗИИ, "Наука Юга России"
Authors: Абрамова Л.М. , Гергия Л.Г. , Мустафина А.Н. , Айба Э.А. , Голованов Я. М.
Published: February 2021

Приведены сведения о прогрессирующем инвазионном неофите североамериканского происхождения Solidago canadensis L., представляющем опасность для кавказского региона. Цель работы – изучение инвазионных популяций вида и сообществ с участием S. canadensis в Республике Абхазия. Исследования проведено стандартными геоботаническими и популяционными методами с применением статистической обработки данных. Solidago canadensis натурализовался в экосистемах низменной прибрежной зоны Черноморского побережья Абхазии и широко распространился в фитоценозах, образуя 2 дериватных сообщества: Solidago canadensis [Acalypho australis–Paspalion digitati / Molinio–Arrhenatheretea] и Solidago canadensis–Phalacroloma annuum [Acalypho australis–Paspalion digitati / Molinio–Arrhenatheretea]. Условия местообитания оказывают влияние на параметры растений S. canadensis, но уровень факторизации невысокий (10,3–46,3 %), что объясняется довольно схожими условиями произрастания вида в разных районах Абхазии. Особи растений морфоструктурно неоднотипны между собой, что свидетельствует о высоком фенотипическом разнообразии ценопопуляций вида. Большинство ценопопуляций процветающие, что подтверждает экологический оптимум для растений S. canadensis в Северо-Западном Закавказье. Расселение золотарника канадского по территории Абхазии и занятие видом устойчивых ценотических позиций в сообществах представляет угрозу для экосистем и биоразнообразия региона.
ОСОБЕННОСТИ РОСТА И РАЗВИТИЯ OPUNTIA ENGELMANNII VAR. LINDHEIMERI (CACTACEAE) В УСЛОВИЯХ ЮЖНОГО БЕРЕГА КРЫМА, "Наука Юга России"
Authors: Багрикова Н.А. , Перминова Я.А. , Чичканова Е.С.
Published: February 2021

Представлены результаты изучения фенологии Opuntia engelmannii var. lindheimeri на особо охраняемой природной территории «Мыс Мартьян», а также дана оценка влияния абиотических факторов (температуры воздуха, продолжительности солнечного сияния, количества осадков) на сезонные ритмы развития растений по данным исследований 2017–2019 гг. В природных условиях Южного берега Крыма изученный вид проходит все фазы сезонного развития, по характеру фенологического развития относится к длительновегетирующим (185–215 дней) весенне-летне-осеннезеленым растениям с периодом зимнего покоя, с ранневесенним сроком пробуждения, кратковременным периодом цветения – 10–31 дней (в июне) – и продолжительным периодом созревания плодов – 53–89 дней (в сентябре – ноябре), тогда как в природных условиях в Северной Америке цветение приходится на июнь – июль, плодоношение – на июль – сентябрь. По результатам дисперсионного, корреляционного и регрессионного анализа установлено, что из рассмотренных абиотических факторов продолжительность солнечного сияния в условиях Южного берега Крыма оказывает влияние на все фазы сезонного развития, тогда как наибольшее комплексное влияние трех факторов выявлено для фаз «начало цветения» и «начало окрашивания плодов». Недостаточное количество осадков в летний период в Крыму, вероятнее всего, приводит к сокращению периода цветения. При дальнейшем потеплении климата существует высокая вероятность распространения изученного вида опунции в других природных зонах Крымского полуострова.
Management of Distal 1/3rd Closed Forearm Fractures in Children above Elbow Plaster Cast versus Below Elbow Plaster Cast
Authors: Memon Abbas , Abro Amir Zaffar , Memon Shakeel Ahmed , Bhutto Irshad Ahmed , Mirjat Ashfaq Hussain , Butt Siraj Ahmed
Published: February 2021

Objective: To determine if below-elbow casts are as effective as above-elbow casts in the treatment of the distal third closed forearm fractures in children.

Materials and Methods: This was a prospective comparative study and was conducted at orthopaedic department of Liaquat University of Medical and Health Sciences (LUMHS). Children 4 to 12 years of age who presented to, distal 1/3rd fractures of the forearm were randomized in order to manage with either an above-elbow or below-elbow cast after closed reduction under fluoroscopic guidance. Radiographic analysis was done for angulation and displacement at the injury time, following reduction, and at subsequent intervals of follow-up. At the fracture level, the cast index for evaluating the cast moulding quality was assessed from the post-reduction radiographs. Variations between post-reduction and final values for displacement and angulation, the range of motion of elbow, forearm and wrists and cast indices between the two groups were compared.

Results: Of total 50 study subjects, 26 underwent above-elbow cast and 24 subjects underwent below-elbow cast techniques. Mean age of above-elbow cast group patients was 9.42 year and the mean age in of below-elbow cast group patients was 9.13 years. 15 male and 11 female patients were present in above-elbow cast group; 14 male and 10 female patients were present in below-elbow cast group. The mean cast index of above-elbow cast group was 0.71 and the mean cast index of below-elbow cast was 0.70. In terms of patient demographics, injury mechanism, characteristics of initial fracture, cast index or shift in displacement and angulation during treatment, no significant variances were observed between both groups. In above-elbow cast group, the mean elbow arc of motion on cast removal at six weeks was only 78° compared to 141.6° in below-elbow cast group. There was a significant decline in arc of motion of elbow joint in above-elbow cast group compared to below-elbow cast group in six weeks which became normal at final follow-up in three months. The complication rates in both the groups were similar.

Conclusion: Below-elbow cast is the safe reliable and cost-effective method of cast immobilization in distal third forearm fractures in the children of 4 to 12 years of age.
Flexographic Printing Contributions in Transistors Fabrication
Authors: Assaifan Abdulaziz K.
Published: February 2021

Transistors are one of the major components of everyday consumer electronics. With the huge demand for low‐cost and flexible consumer electronics, modern industrially‐compatible transistor‐fabrication techniques such as roll‐to‐roll printing techniques must be given due consideration with a view to replacing conventional complex lithography techniques which make use of toxic chemicals. Such traditional methods are not only time‐consuming but also pose a threat to human health. This review article is concerned with offering insights into the deployment of flexographic printing which has been widely used for food packaging and newspaper production, as a cost‐effective technique for the production of transistors. More specifically, it discusses in detail both advantages of the printing technique and its contributions to fabrication of different vital transistor components such as gate, source, drain, semiconductor, and dielectric layers. It also attends to prepatterning of surfaces for the formation of transistor electrodes using the printing technique. Finally, it addresses the challenges associated with implementing such a technique in industry.
Red‐Light‐Stimulated Photonic Synapses Based on Nonvolatile Perovskite‐Based Photomemory
Authors: Hsu Hsin-Tsung , Yang Dong-Lin , Wiyanto Lukius Denny , Chen Jung-Yao
Published: February 2021

Inspired by the low energy consumption, high parallel and fault‐tolerance of visual perception system in human brain, optoelectronic devices integrated with the sensing, memory, and signal processing functionalities become the candidate to emulate functions of photonic synapse. Herein, red‐light‐stimulated nonvolatile perovskite‐based photomemory through optimized thickness of poly(3‐hexylthiophene‐2,5‐diyl)(P3HT) is demonstrated. The device emulates important synaptic functions which can be manipulated by light intensity, light pulse interval, and number of presynaptic spikes. The lower photon energy triggered photonic device paves the way for developing low energy consumption of neuromorphic computing in the future.
Virtual student experiences: A case study of objectives, outcomes, and anticipated consequences
Authors: Shappell Eric , Egan Daniel J. , Eyre Andrew , Nadel Eric , Wittels Kathleen
Published: February 2021

Due to the COVID‐19 pandemic, most in‐person visiting clerkship opportunities have been canceled. Many institutions have developed virtual experiences to fill this void; however, the format and objectives of these experiences are variable. This article describes an education intervention for visiting students where both learner‐oriented and program‐oriented outcomes of a nonclerkship virtual student experience are explored. This intervention consisted of five 1‐hour case‐based teaching sessions in addition to attendance at weekly residency conference over a 1‐week period. The primary outcomes were student ratings of how the experience impacted their 1) perception of the program's educational environment and culture, 2) medical knowledge, and 3) program ranking before and after the experience. Of 24 participants, 15 students (63%) completed the final evaluation, all with positive summative rankings in every domain measured. Of the 15 respondents, 12 (80%) reported an increase in where they would rank the program after the experience compared to before, and nine of 15 (60%) stated that they would rank the program #1 if making a list at the time they completed the final evaluation. Future study should examine long‐term outcomes of these interventions including decisions regarding where students apply, who programs interview, and ranking decisions of students and programs.
Base‐Free Cross‐Couplings of Aryl Diazonium Salts in Methanol: PdII–Alkoxy as Reactivity‐Controlling Intermediate
Authors: Sanhueza Italo A. , Klauck Felix J. R. , Senol Erdem , Keaveney Sinead T. , Sperger Theresa , Schoenebeck Franziska
Published: February 2021

Pd‐catalyzed cross‐coupling reactions of aryl diazonium salts are generally assumed to proceed via cationic PdII intermediates which in turn would be highly reactive in the subsequent transmetalation step. Contrary to this belief, we herein report our observation and rationalization of opposing reactivities of ArN2+ in Suzuki (=effective) and Stille (=ineffective) cross‐couplings in MeOH. Our systematic experimental and computational studies on the roles of transmetalating agent, solvent, base and the likely involvement of in situ formed diazoether derivatives challenge the currently accepted mechanism. Our data suggest that the observed solvent dichotomy is primarily due to PdII‐methoxy intermediates being formed, which are unreactive with arylstannanes, but highly reactive with arylboronic acids, complementing the Suzuki “Pd‐oxy” mechanism with the direct demonstration of transmetalation of a PdII‐alkoxy complex. Lewis acids were found to circumvent this reactivity divergence, promoting efficient couplings regardless of the employed conditions or coupling partners.
Oxygen Reduction Electrocatalysts toward Practical Fuel Cells: Progress and Perspectives
Authors: Zaman Shahid , Huang Lei , Douka Abdoulkader Ibro , Yang Huan , You Bo , Xia Bao Yu
Published: February 2021

Fuel cells are an incredibly powerful renewable energy technology, but their broad applications remains lagging because of the high cost and poor reliability of cathodic electrocatalysts for the oxygen reduction reaction (ORR). This review focuses on the recent progress of ORR electrocatalysts in fuel cells. More importantly, it highlights the fundamental problems associated with the insufficient activity translation from rotating disk electrode to membrane electrode assembly in the fuel cells. Finally, for the atomic‐level in‐depth information on ORR catalysts in fuel cells, potential perspectives are suggested, including large‐scale preparation, unified assessment criteria, advanced interpretation techniques, advanced simulation and artificial intelligence. This review aims to provide valuable insights into the fundamental science and technical engineering for efficient ORR electrocatalysts in fuel cells.
Bio‐adhesive Nanoporous Module: Toward Autonomous Gating
Authors: Jo Hyuna , Kitao Takashi , Kimura Ayumi , Itoh Yoshimitsu , Aida Takuzo , Okuro Kou
Published: February 2021

Here we report a bio‐adhesive porous organic module (GlueCOF) composed of hexagonally packed 1D nanopores based on a covalent organic framework. The nanopores are densely decorated with guanidinium ion (Gu+) pendants capable of forming salt bridges with oxyanionic species. GlueCOF strongly adheres to biopolymers through multivalent salt‐bridging interactions with their ubiquitous oxyanionic species. By taking advantage of its strong bio‐adhesive nature, we succeeded in creating a gate that possibly opens the nanopores through a selective interaction with a reporter chemical and releases guest molecules. We chose calmodulin (CaM) as a gating component that can stably entrap a loaded guest, sulforhodamine B (SRB), within the nanopores (CaMCOF⊃SRB). CaM is known to change its conformation on binding with Ca2+ ions. We confirmed that mixing CaMCOF⊃SRB with Ca2+ resulted in the release of SRB from the nanopores, whereas the use of weakly binding Mg2+ ions resulted in a much slower release of SRB.
Reactions of B2(o‐tolyl)4 with Boranes: Assembly of the Pentaborane(9), HB[B(o‐tolyl)(μ‐H)]4
Authors: Bamford Karlee L. , Qu Zheng‐Wang , Stephan Douglas W.
Published: February 2021

Reactions of the diborane(4) B2(o‐tolyl)4 and monohydridoboranes are shown to give B(o‐tolyl)3 and (o‐tolyl)BR2 (R2=(C8H14) 3, cat 4, pin 5, (C6F5)2 6) as the major products. The corresponding reaction with BH3‐sources gives complex mixtures, resulting from hydride/aryl exchange, dimerization and borane elimination. This led to the isolation of the first tetra‐substituted pentaborane(9) HB[B(o‐tolyl)(μ‐H)]4 8. The reaction pathways are probed experimentally and by computations.
Polymermörtel‐Klebverbindungen für Holz‐Beton‐Verbundbrücken Teil 2
Authors: Kästner Martin , Rautenstrauch Karl
Published: February 2021

Leistungsfähigkeit und Tragverhalten von Holz‐Beton‐Verbundkonstruktionen (HBV) sind entscheidend von der konstruktiven Ausbildung der Verbundfuge abhängig. Die meisten bislang für HBV‐Straßenbrücken entwickelten Verbundlösungen sind durch eine diskontinuierliche Schubübertragung gekennzeichnet, wobei die Schubtragfähigkeit des Holzes nicht optimal ausgenutzt wird. Ziel der im Beitrag vorgestellten Untersuchungen war die Entwicklung von Verbundfugenkonfigurationen mit kontinuierlichem Verbund zwischen Betonfahrbahnplatte und hölzernen Brückenhauptträgern. Zur Vergleichmäßigung der Schubbeanspruchung und zur Vermeidung tragfähigkeitsmindernder Spannungsspitzen im Bereich der Verbundelemente kommen mineralisch gefüllte, toleranzausgleichende Klebmörtel auf Epoxidharzbasis zum Einsatz. Die Beurteilung der Leistungsfähigkeit zweier weiterentwickelter Dübelleistenverbindungen mit Polymermörtelverguss sowie der direkten Polymermörtel‐Klebverbindung von Beton und Holz erfolgte anhand experimenteller und numerischer Untersuchungen. Der erste Teil des Beitrags gibt einen Überblick über die entwickelten Verbundfugenkonfigurationen und geeignete Polymermörtel und fokussiert auf die Ergebnisse der Untersuchungen zum Schubtragverhalten. Im vorliegenden zweiten Teil wird auf Untersuchungen an Biegeträgern eingegangen. Darüber hinaus werden die aus den Ergebnissen abgeleiteten Bemessungsvorschläge und Empfehlungen für die Ausführung vorgestellt.
On the Manganese Dissolution Process from LiMn2O4 Cathode Materials
Authors: Tesfamhret Yonas , Liu Haidong , Chai Zhigang , Berg Erik , Younesi Reza
Published: February 2021

Transition metal (TM) dissolution is a process experienced by most cathode materials based on lithium transition metal oxides. Spinel LiMn2O4 (LMO) is the best‐known cathode material that suffers from TM dissolution. Therefore, LMO is selected here to understand the dissolution process and derive an inductively coupled plasma optical emission spectroscopy (ICP‐OES) method for quantifying dissolved metal ions. Furthermore, the LMO powder is coated with thin Al2O3 films of different thicknesses using atomic layer deposition (ALD) in an attempt to suppress the dissolution of Mn. Two different types of counter electrodes, lithium iron phosphate (LFP) and Li‐metal, were used to investigate the role of the counter electrode on Mn dissolution. HF is identified as the lead cause of Mn dissolution, through comparisons of cells containing LiPF6 or LiClO4 based electrolytes. The results show that Li‐metal counter electrode effectively minimizes the dissolution process via likely consuming HF and H2O impurity. In contradiction to the purpose of the protective Al2O3 thin film coating, surface coated LMO showed higher dissolution of Mn compared to pristine LMO, both in LFP||LMO and Li||LMO configurations. Al2O3 is proposed to generate H2O when reacts with HF. H2O could have the possibility to migrate back in the electrolyte and participate in the hydrolysis of LiPF6, resulting in more HF and thereby more Mn dissolution.
Potassium‐Ion Activating Formation of Fe−N−C Moiety as Efficient Oxygen Electrocatalyst for Zn‐Air Batteries
Authors: Arif Khan Muhammad , Sun Congli , Cai Jian , Ye Daixin , Zhao Kangning , Zhang Guobing , Shi Shanshan , Ali Shah Luqman , Fang Jianhui , Yang Chao , Zhao Hongbin , Mu Shichun , Zhang Jiujun
Published: February 2021

Developing a new synthesis methodology to obtain an economical and stable single atom oxygen reduction reaction (ORR) catalyst is highly desirable. Herein, we develop a general ionic salt assisted template method to obtain M−N−C (M=Fe and Co) catalyst with improved ORR activity. The creation of M−N−C single atom catalyst is highly dependent on the nature of ionic salt templates. Compared with NaCl, KCl can not only act as template, but also create more defect sites for single iron atom to anchor through metallic K‐intercalation activation at elevated temperatures, which results in the generation of more single atomic M−N−C active sites. Furthermore, the ionic salt template‐assisted method leads to the formation of interconnected porous structure with sufficient micropores and a high surface area of 514 m2 g−1. As an ORR and Zn‐air battery catalyst, Fe−N−C−KCl shows a half‐wave potential of 0.877 V and a maximum power density of 185 mW cm−2, respectively, outperforming those of state‐of‐the‐art Pt/C catalyst. The general ionic salt assisted method is a promising strategy for developing efficient and robust catalysts, electrode materials towards economic platinum‐free zinc‐air batteries and other energy storage systems.
Endohedral Hydrogen Bonding Templates the Formation of a Highly Strained Covalent Organic Cage Compound**
Authors: Schäfer Natalie , Bühler Michael , Heyer Lisa , Röhr Merle I. S. , Beuerle Florian
Published: February 2021

A highly strained covalent organic cage compound was synthesized from hexahydroxy tribenzotriquinacene (TBTQ) and a meta‐terphenyl‐based diboronic acid with an additional benzoic acid substituent in 2’‐position. Usually, a 120° bite angle in the unsubstituted ditopic linker favors the formation of a [4+6] cage assembly. Here, the introduction of the benzoic acid group is shown to lead to a perfectly preorganized circular hydrogen‐bonding array in the cavity of a trigonal‐bipyramidal [2+3] cage, which energetically overcompensates the additional strain energy caused by the larger mismatch in bite angles for the smaller assembly. The strained cage compound was analyzed by mass spectrometry and 1H, 13C and DOSY NMR spectroscopy. DFT calculations revealed the energetic contribution of the hydrogen‐bonding template to the cage stability. Furthermore, molecular dynamics simulations on early intermediates indicate an additional kinetic effect, as hydrogen bonding also preorganizes and rigidifies small oligomers to facilitate the exclusive formation of smaller and more strained macrocycles and cages.
Enantioselective Nickel‐Catalyzed anti‐Arylmetallative Cyclizations onto Acyclic Ketones
Authors: Green Harley , Argent Stephen P. , Lam Hon Wai
Published: February 2021

Domino reactions involving nickel‐catalyzed additions of (hetero)arylboronic acids to alkynes, followed by cyclization of the alkenylnickel intermediates onto tethered acyclic ketones to give chiral tertiary‐alcohol‐containing products in high enantioselectivities, are described. The reversible E/Z isomerization of the alkenylnickel intermediates enables overall anti‐arylmetallative cyclization to occur. The ring system of the products are substructures of certain diarylindolizidine alkaloids.
Conformational Switching through the One‐Electron Reduction of an Acridinium‐based, γ‐Cationic Phosphine Gold Complex
Authors: Liu Wei‐Chun , Kim Youngmin , Gabbaï François P.
Published: February 2021

Our efforts in the chemistry of gold complexes featuring ambiphilic phosphine‐carbenium L/Z‐type ligand have led us to consider the reduction of the carbenium moiety as a means to modulate the gold–carbenium interaction present in these complexes. Here, it was shown that the one‐electron reduction of [(o‐Ph2P(C6H4)Acr)AuCl]+ (Acr=9‐N‐methylacridinium) produces a neutral stable radical, the structure of which showed a marked increase in the Au–Acr distance. Related structural changes were observed for the phosphine oxide analogue [(o‐Ph2P(O)(C6H4)Acr]+, the reduction of which interfered with the P=O→carbenium interaction. These structural effects, driven by a reduction‐induced change in the electronic and electrostatic characteristics of the compounds, showed that the charge and accepting properties of the carbenium unit can be modulated. These results highlight the redox‐noninnocence of carbenium Z‐type ligand, a feature that can be exploited to induce specific conformational changes.
Removal of Arsenic from Water Using a Composite of Iron–Manganese Oxide Incorporated Active Rice Husk Silica
Authors: Bui Trung Huu , Pham Van Sy , Thanh‐Nho Nguyen , Trieu Quoc An
Published: February 2021

Low‐cost adsorbents from agricultural by‐products are intensively studied in water treatment, especially in arsenic removal for obtaining safe drinking water. Here, it is reported that a cheap and effective nano‐composite of iron–manganese oxide incorporated active rice husk silica (FMRS) for efficient removal of arsenic (As(III) and As(V)) from water, which is fabricated using a one‐pot synthesis. Fe3+ and Mn4+ in their oxides supported silica structure are successfully characterized. The FMRS (qe = 11.9 mg g−1) shows a remarkable enhancement of arsenic removal compared with the original rice husk ash (qe = 0.4 mg g−1) at initial [As(V)] = 5 mg L−1. The As(III) and As(V) adsorption are in good agreement with both Langmuir and Freundlich non‐linear isotherm models (R2 > 0.98), where the maximum adsorption capacities at pH 7 are found up to 19.1 and 20.3 mg g−1, respectively. The role of Mn4+ in enhancing the As(III) adsorption is also discussed. The FMRS exhibits high selectivity toward arsenic under the influences of other co‐existing anions in water (e.g., chloride, sulfate, and bicarbonate) and sustains a good arsenic removal efficiency during four cycles of the reusability test, suggesting a high potential of the fabricated adsorbent for long‐term removal of arsenic in field application.
Pharmacology of HIV Cure: Site of Action
Authors: Devanathan Aaron S. , Cottrell Mackenzie L.
Published: February 2021

Despite significant advances in HIV treatment over the past 30 years, critical barriers to an HIV cure persist. The HIV reservoir, defined at both the cellular and anatomical level, constitutes the main barrier to cure. While the mechanisms underlying the reservoir are not yet well understood, one theory to explain persistence at the anatomical level is that subtherapeutic exposure to antiretroviral therapy (ART) within certain tissue compartments permits ongoing replication. Characterizing ART pharmacology throughout the body is important in the context of these potential pharmacologic sanctuaries and for maximizing the probability of success with forthcoming cure strategies that rely on latency reversal and require ART to prevent reseeding the reservoir. In this review, we provide a comprehensive overview of ART and latency reversal agent distribution at the site of action for HIV cure (i.e., anatomical sites commonly associated with HIV persistence, such as lymphoid organs and the central nervous system). We also discuss methodologic approaches that provide insight into HIV cure pharmacology, including experimental design and advances within the computational, pharmaceutical, and analytical chemistry fields. The information discussed in this review will assist in streamlining the development of investigational cure strategies by providing a roadmap to ensure therapeutic exposure within the site of action for HIV cure.
Too Much of a Good Thing: Defining Antimicrobial Therapeutic Targets to Minimize Toxicity
Authors: Downes Kevin J. , Goldman Jennifer L.
Published: February 2021

Antimicrobials are a common cause of drug toxicity. Understanding the relationship between systemic antimicrobial exposure and toxicity is necessary to enable providers to take a proactive approach to prevent undesired drug effects. When an exposure threshold has been defined that predicts drug toxicity, therapeutic drug monitoring (TDM) can be performed to assure drug exposure does not exceed the defined threshold. Although some antimicrobials have well‐defined dose‐dependent toxicities, many other exposure‐toxicity relationships have either not been well‐defined or, in some cases, not been evaluated at all. In this review, we examine the relationship between exposures and toxicities for antibiotic, antifungal, and antiviral agents. Furthermore, we classify these relationships into four categories: known association between drug exposure and toxicity such that clinical implementation of a specific exposure threshold associated with toxicity for TDM is supported (category 1), known association between drug exposure and toxicity but the specific exposure threshold associated with toxicity is undefined (category 2), association between drug exposure and toxicity has been suggested but relationship is poorly defined (category 3), and no known association between drug exposure and toxicity (category 4). Further work to define exposure‐toxicity thresholds and integrate effective TDM strategies has the potential to minimize many of the observed antimicrobial toxicities.
Importance of antibody isotypes in antitumor immunity by monocytes and complement using human‐immune tumor models
Authors: Lara Sandra , Anania Jessica C. , Virtanen Alexander , Stenhammar Viktoria , Kleinau Sandra
Published: February 2021

Monoclonal antibodies (mAbs) have revolutionized clinical medicine, especially in the field of cancer immunotherapy. The challenge now is to improve the response rates, as immunotherapy still fails for many patients. Strategies to enhance tumor cell death is a fundamental aim, but relevant model systems for human tumor immunology are lacking. Herein, we have developed a preclinical human immune – three‐dimensional (3D) tumor model (spheroids) to map the efficiency of tumor‐specific isotypes for improved tumor cell killing. Different anti‐CD20 Rituximab (RTX) isotypes alone or in combination, were evaluated for mediating complement‐dependent cytotoxicity and antibody‐dependent phagocytosis by human monocytic cells in 3D spheroids, in parallel with monolayer cultures, of human CD20+ B‐cell lymphomas. We demonstrate that the IgG3 variant of RTX has the greatest tumoricidal effect over other isotypes, and when combined with apoptosis‐inducing RTX‐IgG2 isotype the therapeutic effect can be substantially enhanced. The results show further that the treatment outcome by RTX isotypes is influenced by tumor morphology and expression of the complement inhibitor CD59. Hence, the human immune‐3D tumor model is a clinical relevant and attractive ex vivo system to predict mAbs for best efficacy in cancer immunotherapy.
Iron‐Catalyzed Electrophilic Amination of Sodium Sulfinates with Anthranils
Authors: Liang Baihui , Huang Junjie , Zhu Weidong , Li Yawen , Jiang Lanping , Gao Yang , Xie Feng , Li Yibiao , Chen Xiuwen , Zhu Zhongzhi
Published: February 2021

A practical method for the synthesis of N‐(2‐carbonylaryl) benzenesulfonamides via an iron‐catalyzed electrophilic amination of sodium sulfinates with anthranils is described. This redox‐neutral transformation has high atom efficiency and is achieved under simple and mild reaction conditions. A wide range of anthranils and sodium sulfinates were compatible in this transformation. Moreover, the synthetic potential of this methodology was further demonstrated by the synthesis of various useful N‐heterocycles and derivatives.
Diaryliodonium Salts in Transition‐Metal‐Catalyzed Chelation‐Induced C(sp2/sp3)−H Arylations
Authors: Joshi Asha , De Saroj Ranjan
Published: February 2021

Transition‐metal‐catalyzed Cross‐coupling via directing group assisted C−H bond activation has become an expedient tool in current synthesis to achieve diverse molecular complexity. In this context, chelation‐assisted arylations of C(sp2/sp3)−H bonds have been extensively investigated as aryl/biaryl derivatives are an important contributor in the area of the industry, farming, medicinal and material science. The diaryliodonium salt has been broadly utilized in C(sp2/sp3)−H bond arylation where the reaction proceeds via oxidative addition of aryliodonium salt to chelation induced metallacycle. The proximal/remote C(sp2/sp3)−H bonds in coordination with transition metals are arylated by a range of directing groups in good to excellent yields. In this mini‐review, we have outlined the up to date developments on transition‐metal‐catalyzed chelation assisted C(sp2/sp3)−H bond arylation utilizing diaryliodonium salts as the coupling partner.
What causes the Strength‐is‐Weakness effect in coalition formation: Passive adoption or active selection of self‐serving allocation rules?
Authors: Wissink Joeri , van Beest Ilja , Pronk Tila , van de Ven Niels
Published: February 2021

In coalition formation, bargainers with many resources are often excluded from coalitions (the Strength‐is‐Weakness effect). Literature suggests this effect is driven by high‐resource bargainers using self‐serving allocation rules that backfire, as they prefer equity over equality (while low‐resource bargainers prefer the opposite). Four studies test (1) whether this is actually the case and (2) whether high‐resource bargainers solely consider equitable allocations or whether they consider both equity and equality but actively choose equity as an allocation rule. We find the Strength‐is‐Weakness effect even when equality rules are made salient, strengthening the idea that the high‐resource bargainers actively select equity as their framework for fairness to attempt to maximize their outcomes. The studies, also suggest an additional reason for the exclusion of high‐resource bargainers. We find that high‐resource bargainers are likely avoided because they are expected to bargain self‐servingly, making the low‐resource bargainers seek each other out.
“We are the victims of racism”: Victim categories in negotiating claims about racism against Black‐Africans in India
Authors: Sambaraju Rahul
Published: February 2021

How is racism negotiated by those who are otherwise victims of racism? Social psychologists show the relevance of categorization in negotiating racism. In the present article I focus on a setting where the majority group itself can be considered a target of racism: racism against Black‐Africans in India. I examine how victim categorization of the majority group is developed and used through a membership categorization analysis of broadcast media news debates. Analysis shows that, first, victim categories complicated the use of racial prejudice as an explanation for the attacks. Second, victim categorizations were developed in relation to social groups that were removed from the present setting. These allowed for accomplishing specific actions: denials and rejections of racism, moral concerns in racism, and acceptance of Black‐Africans' claims about racism. Together, the findings show that racism can be negotiated in terms additional to racial/ethnic group membership: as victims or perpetrators of racism.
Empirically derived guidelines for effect size interpretation in social psychology
Authors: Lovakov Andrey , Agadullina Elena R.
Published: February 2021

This study estimates empirically derived guidelines for effect size interpretation for research in social psychology overall and sub‐disciplines within social psychology, based on analysis of the true distributions of the two types of effect size measures widely used in social psychology (correlation coefficient and standardized mean differences). Analysis of empirically derived distributions of 12,170 correlation coefficients and 6,447 Cohen's d statistics extracted from studies included in 134 published meta‐analyses revealed that the 25th, 50th, and 75th percentiles corresponded to correlation coefficient values of 0.12, 0.24, and 0.41 and to Cohen's d values of 0.15, 0.36, and 0.65 respectively. The analysis suggests that the widely used Cohen's guidelines tend to overestimate medium and large effect sizes. Empirically derived effect size distributions in social psychology overall and its sub‐disciplines can be used both for effect size interpretation and for sample size planning when other information about effect size is not available.
Nonenzymatic Electrochemical Sensor for Wearable Interstitial Fluid Glucose Monitoring
Authors: Lei Lanjie , Zhao Chao , Zhu Xiaofei , Yuan Shuai , Dong Xing , Zuo Yinxiu , Liu Hong
Published: February 2021

We report on a nonenzymatic electrochemical sensor for wearable glucose monitoring in interstitial fluid. The sensor exhibited acceptable selectivity and reliability for continuous glucose detection for up to 30 days. The sensor tip is coated with polyurethane, and the biocompatibility of the tip is investigated by tissue staining. A fully integrated wearable glucose monitoring system is developed with a wireless connection with a smartphone. The test results are in agreement with reference methods. So, we believe the sensor is promising for the development of a continuous glucose monitoring system and diabetes management.
Chronic Exposure to Environmental DDT/DDE in 2 Species of Small Rodents: Measures of Contaminant Load, Immune Dysfunction, and Oxidative Stress
Authors: Molina Erica M. , Kavazis Andreas N. , Mendonça Mary T.
Published: February 2021

Persistent contaminants are ubiquitous in our water and soil, and thus chronic exposure to environmentally relevant levels of these contaminants may pose a risk to humans and wildlife. Two species of small mammals (deer mouse, Peromyscus maniculatus and cotton rat, Sigmodon hispidus) were collected from historically dichlorodiphenyltrichloroethane (DDT)-contaminated and reference areas at the Redstone Arsenal (Huntsville, AL, USA), a US Environmental Protection Agency (USEPA)-designated Superfund site. Soil samples taken concurrently with mammal collection from the DDT abatement site exhibited DDT and dichlorodiphenyldichloroethylene (DDE) levels >1 ppm (USEPA total threshold limit concentration for DDT and DDE <1 ppm), whereas soil samples from the reference area had undetectable levels. Liver samples from individuals of both species collected in the contaminated areas also had significantly elevated DDT/DDE levels, with P. maniculatus averaging an approximately 20× greater load than that documented for S. hispidus. Both rodent species collected from the contaminated site had significantly lower total leukocyte counts and total differential blood cell counts (p = 0.01 and p = 0.04, respectively) than those collected from the nearby (~7000-m) reference site. Cellular stress indices also trended higher in both species, suggesting a potential for chronic exposure to DDT to act as a mediator of oxidative damage. The present study provides support to the idea that environmental exposure to low levels of contaminants can cause physiological consequences that may influence immune responsiveness and initiate cellular stress in resident mammals. Environ Toxicol Chem 2021;40:1619–1629. © 2021 SETAC

Abstract

Chronic rodent exposure to dichlorodiphenyltrichloroethanes within the soil has the potential to cause immune dysfunction and increase oxidative stress in rodents inhabiting superfund sites. HSP = heat shock protein; WBC = white blood cell; DDT = dichlorodiphenyltrichloroethane; DDE = dichlorodiphenyldichloroethylene; DDD = dichlorodiphenyldichloroethane.
Design of Chiral NHC‐Carboxylates as Potential Ligands for Pd‐Catalyzed Enantioselective C−H Activation
Authors: Niggli Nadja E. , Baudoin Olivier
Published: February 2021

Despite numerous efforts, the synthesis of scalemic carbo‐ and heterocycles through Pd0‐catalyzed C(sp3)−H activation employing chiral ancillary ligands or chiral bases is still limited. Inspired by the recently reported outstanding performance of IBiox‐type NHC ligands and bifunctional ligands in similar transformations, a new class of bifunctional NHC‐ligands bearing a pendant carboxylate group was designed. A library of 10 imidazolium‐carboxylic acids was obtained in five to six steps from enantiopure l‐tert‐leucinol. In addition, four well‐defined Pd(DMBPA)‐NHC palladacycles were synthesized in good to excellent yields from the corresponding imidazolium precursors. These complexes were tested in a prototypical C(sp3)−H arylation reaction, and the most active one afforded the indoline product in low yield but significant enantioselectivity. These new bifunctional NHCs could find broader applications in catalytic enantioselective transformations occurring under milder conditions.
Evaluation of the temporal variations of groundwater storage and its interactions with climatic variables using GRACE data and hydrological models: A study from Turkey
Authors: Khorrami Behnam , Gunduz Orhan
Published: February 2021

Monitoring of the fluctuations of groundwater storage is particularly important in arid and semi‐arid regions where water scarcity brings about various challenges. Remote sensing data and techniques play a preponderant role in developing solutions to environmental problems. The launch of Gravity Recovery and Climate Experiment (GRACE) satellites has eased the remote monitoring and evaluation of groundwater resources with an unprecedented precision over large scales. Within the scope of the current study, the latest release (RL06) of GRACE mass concentrations (Mascons) from Jet Propulsion Laboratory (JPL) dataset as well as Global Land Data Assimilation System (GLDAS) models of Noah and Catchment Land Surface Model (CLSM) were used to provide Groundwater Storage Anomalies (GWSA) over Turkey. The temporal interactions of the estimated GWSA with the climatic variables of precipitation and temperature (derived from the reanalysis datasets of CHELSA [Climatologies at High resolution for the Earth's Land Surface Areas] and FLDAS [the Famine Early Warning Systems Network Land Data Assimilation System], respectively) were investigated statistically. The results suggest that there is a descending trend (from 2003 to 2016) for Terrestrial Water Storage Anomalies (TWSA) and GWSA over Turkey with a total loss of 11 and 6 cm of water, respectively. The statistical analysis results also indicate that the monthly variations of GWSA over Turkey are highly correlated with precipitation and temperature at 2‐month lag. The analysis of the climatology (long‐term) values of monthly GWSA, precipitation and temperature also revealed high agreement between the variables.
Supply flexibility in the shale patch: Evidence from North Dakota
Authors: Bjørnland Hilde C. , Nordvik Frode Martin , Rohrer Maximilian
Published: February 2021

This paper provides new results to the literature, showing that output flexibility in oil production depends on the extraction technology. In particular, constructing a novel well‐level monthly production dataset covering more than 16,000 crude oil wells in North Dakota, we find supply elasticity of shale wells to be positive and in the range of 0.3–0.9, depending on wells and firms characteristics. We find no such responses for conventional wells. We interpret the supply pattern of shale oil wells to be consistent with the Hotelling theory of optimal extraction. Reserves are an inventory, and the decision to produce is an intertemporal choice of when to draw down below‐ground inventory.
PEG That Reaction: A Case Series of Allergy to Polyethylene Glycol
Authors: Cox Fionnuala , Khalib Khairin , Conlon Niall
Published: February 2021

Polyethylene glycol (PEG), also known as macrogol, is an excipient in numerous medications, health care products, cosmetics, and foods. It acts as an inert bulking, or stabilizing, agent. Despite its ubiquity, including in 2 of the newly launched vaccines against SARS‐CoV‐2, awareness of PEG allergy remains low. We present 6 cases of acute hypersensitivity to PEG. Accurate diagnoses in these cases posed a challenge, and although the triggering agents differed, PEG was demonstrated as the common culprit. All cases were female, with a mean age of 36.4 years. Four patients were originally suspected to have nonsteroid anti‐inflammatory drug allergy, and 2 had a history of chronic spontaneous urticaria and angioedema. Biphasic allergic reactions featured prominently in this case series. Diagnosis relies on a high index of suspicion leading to a focused clinical history, supported by skin tests with PEG solutions to demonstrate sensitization. This case series highlights important clinical features of this rare, potentially serious, and increasingly recognized excipient allergy.