bluuebunny/crossref_metadata_2025 huggingface dataset:
Zwitterionic poly(carboxybetaine) microgels for enzyme (chymotrypsin) covalent immobilization with extended stability and activity
Authors: Erfani Amir , Zarrintaj Payam , Seaberg Joshua , Ramsey Joshua D. , Aichele Clint P.
Published: February 2021

There is emerging evidence that biocompatible zwitterionic materials can prevent nonspecific interactions within protein systems and increase protein stability. Here, a zwitterionic microgel was synthesized from poly (carboxybetaine methyl methacrylate) (pCB) using an inverse emulsion, free radical polymerization reaction technique. The microgel was loaded with a model enzyme, α‐chymotrypsin (ChT), using a post‐fabrication loading technique. A reaction scheme was developed and studied for covalent immobilization of ChT within the microgel. Confocal laser microscopy studies showed that immobilized ChT (i‐ChT) was distributed within the hydrogel. The enzyme‐immobilized microgels showed excellent reusability (72% of its initial activity after 10 uses) and could undergo several freezing/drying/rehydration cycles while retaining enzymatic activity. The i‐ChT activity, half‐life, and conformational stability were studied at varying pH and temperatures with results compared to free ChT in buffer. ChT immobilized within pCB hydrogel showed increased enzymatic stability as observed by a 13°C increase in the temperature at which i‐ChT loses activity compared to free ChT. Furthermore, enzyme half‐life increased up to seven‐fold for the pCB immobilized ChT, and the increased stability resulted in higher activity at elevated pH. The i‐ChT was most active at pH of 8.5 and was partially active up to the pH of 10.2.
Polymer matrices on the basis of polyacrylamide and β‐cyclodextrin‐containing pseudorotaxane for prolonged drug release: Synthesis and properties
Authors: Sinelnikov Sergii , Orel Luydmila , Kobrina Larisa , Boiko Valentyna , Riabov Sergii , Shtompel Volodymir , Povnitsa Olga , Zagorodnya Svetlana
Published: February 2021

Polymer cross‐linked matrices based on polyacrylamide (PAA) and β‐cyclodextrin‐pseudorotaxane have been designed. The structure and properties of the objects synthesized were confirmed and studied by a series of methods, involving ultraviolet‐, Fourier transform infrared‐spectroscopy, thermal mass spectrometry, DSC, X‐ray diffraction analysis (WAXS and SAXS). Desorption kinetics (especially significant slowing of desorption process) of some drugs, like metoprolol succinate and loratadine from obtained polymer matrices is shown to be optimal with 10 wt% β‐CD‐pseudorotaxane in their structure.
Rational Synthesis of “Grape‐like” Ni2V2O7 Microspheres as High‐capacity Anodes for Rechargeable Lithium Batteries
Authors: Xia Dawei , Wang Dongdong , Liu Wenlong , Gong Feng
Published: February 2021

Vanadates have received booming attention recently as promising materials for extensive electrochemical devices such as batteries and electrocatalysis. However, the enormous difficulties of achieving pure‐phase transition metal vanadates, especially for nickel‐based, hinder their exploitations. Herein, for the first time, by controlling the amount of ethylene glycol (EG) and reaction time, grape‐like Ni2V2O7 (or V2O5/Ni2V2O7) microspheres were rationally fabricated. It is demonstrated that the EG can chelate both Ni2+ and VO3− to form organometallic precursors. As anode in lithium‐ion batteries (LIBs), it could deliver superior reversible capacity of 1050 mAh/g at 0.1 A/g and excellent rate capability of 600 mAh/g at 4 A/g. The facile hydrothermal synthesis broadens the material variety of nickel vanadates and offers new opportunities for their wider applications in electrochemistry.
Axial ring‐down modes in general relativity and in its pseudo‐complex extension
Authors: Hess Peter O. , López‐Moreno Enrique
Published: February 2021

We calculate the axial ring‐down frequencies of the merger of two black holes, using a modified version of the pseudo‐complex General Relativity (pc‐GR) and comparing it with the standard General Relativity (GR). The path, on how to determine the axial modes, serve as a starting point for more general extensions of GR, involving additions of r‐dependent functions to g00.
Primordial black holes and their formation
Authors: Erfani Encieh
Published: February 2021

With the discovery of gravitational waves from merging pairs of massive black holes, the interest in the question of whether Primordial Black Holes (PBHs) could constitute the Dark Matter (DM) has recently been revived. I will review the different mechanisms for (DM) PBHs formation with a focus on inflation which can source the required large density fluctuations for PBHs formation. I will also explain the excursion set theory as a new formalism for the formation of DM PBHs.
Study of diffractive gluon jet production in electron‐ion collisions
Authors: Peccini Guilherme M.
Published: February 2021

In this work, we investigate the diffractive gluon jet production in electron‐ion collisions at the energies of the EIC, LHeC, HE‐LHeC, and FCC‐eA, assuming that the diffractive mass is much larger than the photon virtuality. In addition, we apply a model inspired in the GBW parametrization to describe the dipole amplitude, showing that the diffractive cross section is highly sensitive to the saturation scale. Furthermore, we verify that it is possible to extract this scale from the experiment.
„Sieben Plagen auf einmal schlagen“ – Theatrale Hygienepropaganda und Infektionskrankheiten in der Sowjetunion der 1920 er–40 er Jahre**
Authors: Polianski Igor J. , Tutorskaya Maria , Kosenko Oxana
Published: February 2021

This paper explores the role and impact of the official Soviet hygiene propaganda during the first three decades after the October Revolution, taking as an example theatrical performances about infectious diseases. In the Bolshevik Great Experiment of the 1920s–30s, the creation of a “Soviet body” optimized according to aesthetic and medical‐hygienic norms was one of the core parts of the socialist project. For that purpose, hygiene campaigns were organized to promote hygiene and cleanliness with posters, leaflets, mobile exhibitions and lectures. Moreover, starting in the 1920s the theatrical performances were demonstrated in open‐air theatres and clubhouses for workers and farmers. Even in the kolkhoz fields agitprop‐revues, agit‐trials, living newspapers and didactic plays were performed. Many of them addressed the issues of epidemics. To popularize medical knowledge, special theatres of sanitary education were opened in Moscow and other cities of the country in the mid‐1920s–30s. Using archival materials of the Moscow Theatre for Sanitary Culture (1925–1947), the article shows theatrical techniques for producing evidence used in performances, bacteriological coding of political antagonisms on sanitary stages and transformations of everyday cultural practices in theatrical hygiene propaganda.
In‐silico media optimization for continuous cultures using genome scale metabolic networks: The case of CHO‐K1
Authors: Pérez‐Fernández Bárbara A. , Fernandez‐de‐Cossio‐Diaz Jorge , Boggiano Tammy , León Kalet , Mulet Roberto
Published: February 2021

The cell culture is the central piece of a biotechnological industrial process. It includes upstream (e.g. media preparation, fixed costs, etc.) and downstream steps (e.g. product purification, waste disposal, etc.). In the continuous mode of cell culture, a constant flow of fresh media replaces culture fluid until the system reaches a steady state. This steady state is the standard operation mode which, under very general conditions, is a function of the ratio between the cell density and the dilution rate and depends on the media supplied to the culture. To optimize the production process it is widely accepted that the concentration of the metabolites in this media should be carefully tuned. A poor media may not provide enough nutrients to the culture, while a media too rich in nutrients may be a waste of resources because, either the cells do not use all of the available nutrients, or worse, they over‐consume them producing toxic byproducts. In this study, we show how an in‐silico study of a genome scale metabolic network coupled to the dynamics of a chemostat could guide the strategy to optimize the media to be used in a continuous process. Given a known media we model the concentrations of the cells in a chemostat as a function of the dilution rate. Then, we cast the problem of optimizing the production process within a linear programming framework in which the goal is to minimize the cost of the media keeping fixed the cell concentration for a given dilution rate in the chemostat. We evaluate our results in two metabolic models: first a simplified model of mammalian cell metabolism, and then in a realistic genome‐scale metabolic network of mammalian cells, the Chinese hamster ovary cell line. We explore the latter in more detail given specific meaning to the predictions of the concentrations of several metabolites.
Reverse logistics, organizational culture and firm operational performance: Some empirical evidence
Authors: Saruchera Fanny , Asante‐Darko Disraeli
Published: February 2021

As the supply chain environment is increasingly becoming uncertain and globally competitive, reverse logistics (RL) practices, which constitute a substantial component of Green Supply Chain Management (GSCM), have been widely recognized as crucial in achieving sustainable competitive advantage. While past studies have proven the positive relationship between properly implemented RL and firm's environmental efficiency and overall competitiveness, developing, maintaining, and integrating RL into the organization's supply chain operations come at a cost and institutional commitment. This study seeks to provide evidence on how RL and organizational culture (OC) provide benefits specifically to the operational performance (OP) of an organization. The study addresses this, first, by an empirical examination of the direct effects of RL practices on firm OP and, then, by further examining whether RL practices' influence on OP is strengthened by OC. The study uses dataset gathered from 213 firms across the service and manufacturing sectors in the Ghanaian economy using a structured questionnaire. The study adopts confirmatory factor analysis (CFA) in addition to partial least square structural equation modelling (PLS‐SEM) in analysing the study's measurement model and in estimating the resultant structural model. The study concludes that implementing RL practices positively influences the OP of the firm, while OC strengthens such influence. This study expands the RL literature by obtaining the results for the conceptual model and dealing with the implication from a developing economy's perspective, hence supplementing the growing body of knowledge.
Holistic representation in juvenile defense: An evaluation of a multidisciplinary children's defense team
Authors: Phillippi Stephen , Thomas Casey L. , Yoshida Yilin , Afaneh Hasheemah
Published: February 2021

This study describes the results of an evaluation of a holistic defense model for juvenile clients. Longitudinal, retrospective analysis of de‐identified data from clients (N = 308) measured individual variable outcomes, relationships, and project performance. Bivariate and multivariate analyses examined the strength of association and interrelationships among client and defense team variables. Findings indicate that holistic defense was significantly associated with improved outcomes among juvenile clients, including increased mental health assessment resulting in treatment, increased employment and educational attainment, and decreased odds of recidivism. Favorable court or dispositional outcomes, including lower adjudication or early termination from custody, were also reported. Further practice‐level, controlled research is necessary to evaluate these models and offer comparison to other models for holistic defense.
A phase 2 trial of trifluridine/tipiracil plus nivolumab in patients with heavily pretreated microsatellite‐stable metastatic colorectal cancer
Authors: Patel Manish R. , Falchook Gerald S. , Hamada Kensuke , Makris Lukas , Bendell Johanna C.
Published: February 2021

Background

Microsatellite‐stable (MSS) colorectal cancer (CRC) tends to be poorly immunogenic, with limited treatment options. In MSS CRC xenograft models, trifluridine/tipiracil (FTD/TPI) plus programed death 1 inhibitors resulted in synergistic antitumor activity and increased tumor immunogenicity. This phase 2 study evaluated FTD/TPI plus nivolumab in patients with MSS metastatic CRC.

Methods

This single‐arm, safety lead‐in study used a Simon's two‐stage design (enrolling 6 patients in the safety lead‐in, proceeding to stage 2 if ≥2 of the first 15 patients achieved a partial or complete response per immune‐related response criteria [irRC] within 6 months). Patients with histologically proven MSS mCRC, and disease progression after ≥2 prior chemotherapy regimens received FTD/TPI (35 mg/m2 twice daily; days 1–5 and 8–12 every 28 days) plus nivolumab (3 mg/kg every 2 weeks).

Results

Between August 2016 and January 2017, 18 patients (50% men; median age 56.5 years) were enrolled; 72% had colon cancer and 56% had KRAS mutations. All patients received treatment (median, 2.5 cycles [range, 1–8]). No dose‐limiting toxicities were observed in the study. The most frequent adverse events (AEs) of any cause and grade were nausea (67%), diarrhea (61%), and neutropenia (50%); 13 patients (72%) experienced grade ≥3 AEs. No patients discontinued treatment because of AEs. No patient achieved a tumor response (either per Response Evaluation Criteria in Solid Tumors [RECIST] or irRC), and the study did not progress to the second stage. Stable disease was achieved in 8 patients per irRC and in 10 patients per RECIST. Median progression‐free survival was 2.2 months (95% CI, 1.8–6.0 months) per irRC and 2.8 months (95% CI, 1.8–5.1 months) per RECIST.

Conclusion

Patients with refractory MSS metastatic CRC failed to experience clinical benefit with FTD/TPI plus nivolumab, although safety data in this population indicated tolerability and feasibility of this combination.

Trial registration number

NCT02860546.
Modeling crowd emotion from emergent event video
Authors: Zhuo Lin , Liu Zhen , Liu Tingting , Hung Chih‐Chieh , Chai Yanjie
Published: February 2021

In emergency situation, mass panic often causes more causalities than the disaster itself. The crowd emotional model could be used to simulate how crowd behavior in emergency scenarios and be helpful for developing crowd evacuation plans in emergency situations. However, existing crowd emotional models usually set model parameters in an empirical manner and are not validated by real cases. In this paper, a crowd emotional model is proposed to simulate the crowd movement in outdoor emergency situations. First of all, the crowd entropy and the movement difference are proposed to describe the emotional impact of the crowd scene on the agents. The perception of vision and hearing are considered, and the calculation formulas of the agent's emotional intensity and crowd emotional contagion are proposed. By calculating individual trajectories in the real video, the cumulative differences between the movements of the real crowd and the corresponding virtual crowd are analyzed. At last, a multi‐parameter optimization method is implemented by the differential evolution algorithm. To verify the parameters in models, three videos which are generated from three real cases, including explosion attack, shooting incident, and crowd disturbance are selected for experimental verification. The results showed that the proposed model could be a feasible method for optimizing parameters to simulate the emergency scenario.
Westalsan: A New Acetylcholine Esterase Inhibitor from the Endophytic FungusWesterdykella nigra
Authors: Sallam Amal , Sabry Mohamed A. , Galala Amal A.
Published: February 2021

A new cytochalasan alkaloid, westalsan (1), along with two known cytochalasan compounds, phomacin B (2) and 19‐hydroxy‐19,20‐dihydrophomacin C (3), were isolated from the solid rice culture ofWesterdykella nigra, a marine‐derived endophytic fungus, isolated from the roots of mangroveAvicennia marina(Forssk.) Vierh. The structures of compounds1–3were established on the basis of extensive 1D and 2D NMR spectroscopic techniques in combination with HR‐ESI‐MS. The ability of the isolated compounds to inhibit acetylcholine esterase activity was evaluated. Compound3showed the highest acetylcholine esterase inhibitory activity (IC500.056±0.003 μM), followed by compound1(IC500.088±0.005 μM) and compound2(IC500.140±0.007 μM) compared to donepezil (IC500.035±0.002 μM). This was further confirmed by molecular docking experiment.
Intrinsic Fluorescence of the Active and the Inactive Functional Forms of Human Thymidylate Synthase
Authors: Vitiello Simone , Caselli Monica , Pavesi Giorgia , Santucci Matteo , Ferrari Stefania , Paola Costi Maria , Ponterini Glauco
Published: February 2021

The observables associated with protein intrinsic fluorescence – spectra, time decays, anisotropies – offer opportunities to monitor in real time and non‐invasively a protein‘s functional form and its interchange with other forms with different functions. We employed these observables to sketch the fluorometric profiles of two functional forms of human thymidylate synthase (hTS), a homodimeric enzyme crucial for cell proliferation and thus targeted by anticancer drugs. The protein takes an active and an inactive form. Stabilization of the latter by peptides that, unlike classical hTS inhibitors, bind it at the monomer/monomer interface offers an alternative inhibition mechanism that promises to avoid the onset of drug resistance in anticancer therapy. The fluorescence features depicted herein can be used as tools to identify and quantify each of the two protein forms in solution, thus making it possible to investigate the kinetic and thermodynamic aspects of the active/inactive conformational interchange. Two examples of fluorometrically monitored interconversion kinetics are provided.
GPR39 promotes cardiac hypertrophy by regulating the AMPK–mTOR pathway and protein synthesis
Authors: Liao Hongjuan , Gao Weinian , Ma Jie , Xue Hongyuan , Wang Yi , Huang Dai , Yan Fang , Ye Yuquan
Published: February 2021

Hypertrophic growth of the cardiomyocytes is one of the core mechanisms underlying cardiac hypertrophy. However, the mechanism underlying cardiac hypertrophy remains not fully understood. Here we provided evidence that G protein‐coupled receptor 39 (GPR39) promotes cardiac hypertrophy via inhibiting AMP‐activated protein kinase (AMPK) signaling. GRP39 expression is overexpressed in hypertrophic hearts of humans and transverse aortic constriction (TAC)‐induced cardiac hypertrophy in mice. In neonatal cardiomyocytes, adenovirus‐mediated overexpression of GPR39 promoted angiotensin II‐induced cardiac hypertrophy, while GPR39 knockdown repressed hypertrophic response. Adeno‐associated virus 9‐mediated knockdown of GPR39 suppressed TAC‐induced decline in fraction shortening and ejection fraction, increase in heart weight and cardiomyocyte size, as well as overexpression of hypertrophic fetal genes. A mechanism study demonstrated that GPR39 repressed the activation of AMPK to activate the mammalian target of rapamycin (mTOR) and ribosomal protein S6 kinase β‐1 (S6K1), subsequently promoted de novo protein synthesis. Inhibition of mTOR with rapamycin blocked the effects of GPR39 overexpression on protein synthesis and repressed cardiac hypertrophy. Collectively, our findings demonstrated that GPR39 promoted cardiac hypertrophy via regulating the AMPK–mTOR–S6K1 signaling pathway, and GRP39 can be targeted for the treatment of cardiac hypertrophy.
An ultra‐low‐profile 0.85 mm Nano Hydro balloon to treat wire‐crossable balloon‐uncrossable lesions: A useful tool in CTO armamentarium
Authors: Adusumalli Srikanth , Dautov Rustem
Published: February 2021

Balloon uncrossable lesions are commonly encountered during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). A sequential strategy and planning are required to tackle such lesions. We present a case series of severely calcified, device uncrossable lesions where the traditional strategies failed and an ultra‐low‐profile (0.85 mm) balloon was crucial to successful PCI. To our best knowledge, this is the first case series describing the use of this balloon in real world.
Outcomes of in‐hospital cardiac arrest in COVID‐19 patients: A proportional prevalence meta‐analysis
Authors: Mir Tanveer , Sattar Yasar , Ahmad Javeed , Ullah Waqas , Shanah Layla , Alraies M Chadi , Qureshi Waqas T.
Published: February 2021

Background

Limited epidemiological data are available on the outcomes of in‐hospital cardiac arrest (CA) in COVID‐19 patients.

Methods

We performed literature search of PubMed, EMBASE, Cochrane, and Ovid to identify research articles that studied outcomes of in‐hospital cardiac arrest in COVID‐19 patients. The primary outcome was survival at discharge. Secondary outcomes included return of spontaneous circulation (ROSC) and types of cardiac arrest. Pooled percentages with a 95% confidence interval (CI) were calculated for the prevalence of outcomes.

Results

A total of 7,891 COVID patients were included in the study. There were 621 (pooled prevalence 8%, 95% CI 4–13%) cardiac arrest patients. There were 52 (pooled prevalence 3.0%; 95% CI 0.0–10.0%) patients that survived at the time of discharge. ROSC was achieved in 202 (pooled prevalence 39%;95% CI 21.0–59.0%) patients. Mean time to ROSC was 7.74 (95% CI 7.51–7.98) min. The commonest rhythm at the time of cardiac arrest was pulseless electrical activity (pooled prevalence 46%; 95% 13–80%), followed by asystole (pooled prevalence 40%; 95% CI 6–80%). Unstable ventricular arrhythmia occurred in a minority of patients (pooled prevalence 8%; 95% CI 4–13%).

Conclusion

This pooled analysis of studies showed that the survival post in‐hospital cardiac arrest in COVID patients is dismal despite adequate ROSC obtained at the time of resuscitation. Nonshockable rhythm cardiac arrest is commoner suggesting a non‐cardiac cause while cardiac related etiology is uncommon. Future studies are needed to improve the survival in these patients.
Thermal exposure values for predicting changes in rice end‐use properties during drying
Authors: Graham‐Acquaah Seth , Siebenmorgen Terry J. , Mauromoustakos Andronikos , Wang Ya‐Jane
Published: February 2021

Background and objectives

Rough rice may incur various degrees of thermal exposure during heated‐air drying, which may cause variations in end‐use properties. This study employed a recently proposed method to quantify thermal exposure incurred during drying and its effects on rice end‐use properties.

Findings

Greater drying air temperatures and longer drying durations increased thermal exposure (GATE) values; the higher the GATE value, the more moisture lost during drying. Increasing GATE values reduced head rice yield (HRY). The most notable (≥10%) reductions in HRY occurred when GATE values were ≥30 min. Additionally, increasing GATE values increased peak and breakdown viscosities of rice but decreased both setback viscosity and rice gel strength; the impact of drying on end‐use properties was of most practical importance (≥10% change) when GATE values were ≥40 min.

Conclusions

The proposed GATE values would permit comparisons of the effects of thermal exposure on rice milling and end‐use properties to facilitate predictions of changes in these properties due to heated‐air drying.

Significance and novelty

Differences in heated‐air drying conditions contribute to the inconsistencies in functionality that hinder the wide use of rice in end‐use, gluten‐free product development. This study shows that thermal exposure (GATE) values could be useful for quantifying and comparing cumulative heat‐exposure during drying to facilitate predictions of changes in rice properties.
Prolonged encephalopathy and associated nonconvulsive seizures from suspected pregabalin and tapentadol: Two case reports and review of literature
Authors: Haji Kavi , Muthu Sachin , Banakh Iouri , Tiruvoipati Ravindranath
Published: February 2021

A combination of pregabalin and tapentadol may be associated with prolonged encephalopathy.
Effect of S‐1 on blood levels of phenobarbital and phenytoin: A case report
Authors: Shiraiwa Ken , Ono Hiroyuki , Tanaka Ryota , Fujinaga Atsuro , Hiratsuka Takahiro , Tatsuta Ryosuke , Inomata Masafumi , Itoh Hiroki
Published: February 2021

Drug‐drug interaction of fluorinated pyrimidine anticancer agents with phenytoin is well known, but interaction with phenobarbital is limited. We describe a case showing increases in plasma phenobarbital as well as phenytoin concentrations during preoperative S‐1 (tegafur/gimeracil/oteracil) and radiation therapy for rectal cancer.
Mononuclear Dysprosium Alkoxide and Aryloxide Single‐Molecule Magnets
Authors: Parmar Vijay S. , Mills David P. , Winpenny Richard E. P.
Published: February 2021

Recent studies have shown that mononuclear lanthanide (Ln) complexes can be high‐performing single‐molecule magnets (SMMs). Recently, there has been an influx of mononuclear Ln alkoxide and aryloxide SMMs, which have provided the necessary geometrical control to improve SMM properties and to allow the intricate relaxation dynamics of Ln SMMs to be studied in detail. Here non‐aqueous Ln alkoxide and aryloxide chemistry applied to the synthesis of low‐coordinate mononuclear Ln SMMs are reviewed. The focus is on mononuclear DyIII alkoxide and aryloxide SMMs with coordination numbers up to eight, covering synthesis, solid‐state structures and magnetic attributes. Brief overviews are also provided of mononuclear TbIII, HoIII, ErIII and YbIII alkoxide and aryloxide SMMs.
Designed Construction of SrTiO3/SrSO4/Pt Heterojunctions with Boosted Photocatalytic H2 Evolution Activity
Authors: Cai Jingyi , Wei Haoshan , Zhang Yong , Cai Rui , Zhang Xueru , Wang Yan , Liu Jiaqin , Tan Hark Hoe , Xie Ting , Wu Yucheng
Published: February 2021

Efficient separation of photogenerated electron–hole pairs is a crucial factor for high‐performance photocatalysts. Effective electron–hole separation and migration could be achieved by heterojunctions with suitable band structures. Herein, a porous SrTiO3/SrSO4 heterojunction is prepared by a sol‐gel method at room temperature followed by an annealing process. XRD characterization suggests high crystallinity of the heterostructure. A well‐defined interface between the two phases is confirmed by high‐resolution (HR)TEM. The photocatalytic H2 evolution productivity of the SrTiO3/SrSO4 heterojunction with Pt as co‐catalyst reaches 396.82 μmol g−1 h−1, which is 16 times higher than that of SrTiO3/Pt. The boosted photocatalytic activity of SrTiO3/SrSO4/Pt can be ascribed to the presence of SrSO4, which promotes the transfer and migration of photogenerated carriers by forming the heterojunction and porous structure, which provides a large amount of active sites. This novel porous heterostructure brings new ideas for the development of high‐efficiency photocatalysts for H2 release.
The Role of the −OH Groups within Mn12Clusters in Electrocatalytic Water Oxidation
Authors: Gluz Naama , Christou George , Maayan Galia
Published: February 2021

The formidable reactivity of the oxygen‐evolving center near photosystem II is largely based on its protein environment that stabilizes it during catalysis. Inspired by this concept, the water‐solubleMn12clusters Mn12O12(O2CC6H3(OH)2)16(H2O)4(3,5DHMn12) and Mn12O12(O2CC6H3(OH)3)16(H2O)4(3,4,5THMn12) were developed as efficient electrocatalysts for water oxidation. In this work, the role of the −OH groups in the electrocatalytic process was explored by describing the structural and electrocatalytic properties of two newMn12clusters,3,4DHMn12and2,3DHMn12, having one −OH group in themetaposition relative to the benzoate‐Mn moiety, and one at theparaororthoposition, respectively. The Mn centers in3,4DHMn12were discovered to have lower oxidation potential compared with those in2,3DHMn12, and thus,3,4DHMn12can catalyze water oxidation with higher rate and TON than2,3DHMn12. Hence, the role of the −OH groups in the electrocatalysis was established, being involved in electronic stabilization of the Mn centers or in proton shuttling.
Electrochemically Enabled One‐Pot Multistep Synthesis of C19 Androgen Steroids
Authors: Sommer Florian , Kappe C. Oliver , Cantillo David
Published: February 2021

The synthesis of many valuable C19 androgens can be accomplished by removal of the C17 side chain from more abundant corticosteroids, followed by further derivatization of the resulting 17‐keto derivative. Conventional chemical reagents pose significant drawbacks for this synthetic strategy, as large amounts of waste are generated, and quenching of the reaction mixture and purification of the 17‐ketosteroid intermediate are typically required. Herein, we present mild, safe, and sustainable electrochemical strategies for the preparation of C19 steroids. A reagent and catalyst free protocol for the removal of the C17 side chain of corticosteroids via anodic oxidation has been developed, enabling several one‐pot, multistep procedures for the synthesis of androgen steroids. In addition, simultaneous anodic C17 side chain cleavage and cathodic catalytic hydrogenation of a steroid has been demonstrated, rendering a convenient and highly atom economic procedure for the synthesis of saturated androgens.
Frischluftzufuhr besser nicht von oben
Authors: Schmitz Kathrin
Published: February 2021

In einer aktuellen Stellungnahme analysiert der Arbeitsausschuss Feinstäube (AAF) den Aerosol‐Transmissionspfad der Corona‐Pandemie genauer. Die Expertinnen und Experten gehen auf Gegenmaßnahmen ein und erläutern, wie sich durch Masken, richtiges Lüften, geeignete Luftreinigung und Überkopfabsaugungen die Aerosollast und damit die Übertragung verhindern lässt. Das Papier steht kostenfrei zum Download zur Verfügung.
Den Kreislauf schließen
Authors: Haubensak Silke , Schober Dennis , Sturm Michael , Schuhen Katrin
Published: February 2021

Mikroplastik ist in aller Munde und gleichzeitig ein hochkomplexes Thema. Wir essen, trinken und atmen Mikroplastik – jeder von uns, jeden Tag. Diese vielen kleinen Kunststoffpartikel mit einer Größe kleiner als 5 mm befinden sich fein verteilt in Boden
Energieeffizienz kann man herbeisteuern
Authors: Schimmer Oliver , Hauser Jan
Published: February 2021

Drehzahlgeregelte Kompressoren gelten oft als Wunderwaffe, wenn es darum geht, Energie zu sparen. Doch falsch betrieben verbrauchen sie mehr Energie als herkömmliche Geräte. Erst eine intelligente Übergeordnete Steuerung schöpft das Potenzial drehzahlgere
Universalwerkzeug bei Feldeinsätzen
Authors: Gampp Stefan , Kraftschik Florian
Published: February 2021

Die fortschreitende Digitalisierung von Prozessanlagen führt dazu, dass immer mehr Daten produziert werden. Jedoch werden die daraus erwachsenden Möglichkeiten noch immer wenig genutzt und in den Anlagen schlummern große Produktivitätspotentiale. Dies gil
Digitale Abnahmen
Authors: Rüsenberg Stefan
Published: February 2021

Corona macht Abnahmensicherheitsrelevanter Anlagen bedeutend komplizierter und letztlich auch risikoreicher für alle Beteiligten. Die Lösung: Digitale Abnahmen.
Si/FeSi2 Nanoparticles Prepared by Thermal Plasma with Stress‐releasing Effect for Li‐ion Storage
Authors: Du Yu , Yang Zongxian , Bai Liuyang , Ding Fei , Jin Huacheng , Yang Yijun , Lam Tran Dai , Hou Guolin , Yuan Fangli
Published: February 2021

Silicon (Si) anode materials have been extensively studied due to high capacity and abundant reserves. Herein, inspired by the Li+‐inert components, we design a novel silicon/iron silicide nanoparticles (Si/FeSi2 NPs) prepared by thermal plasma to achieve stress‐releasing effect. The Si/FeSi2 NPs is composed of Si and FeSi2 which exhibits superhigh Initial Coulomb Efficiency (ICE, 89%) with a capacity of 1121 mAh g−1 after 850 cycles. The mechanism of the FeSi2 phase in the Si/FeSi2 NPs is studied by using finite element modelling creatively, demonstrating that the FeSi2 phase can buffer the volume expansion effectively by reducing the stress concentration on the particles surface and releasing internal stress of particles, thus maintaining structural integrity. After combining with carbon coating layer, the Si/FeSi2/carbon/graphite materials (Si/FeSi2/C/G) can achieve superior electrochemical performances. This work provides new insight into the development of the structural stable Si‐alloy anodes towards LIBs applications.
The Gauche Effect in XCH2CH2X Revisited
Authors: Rodrigues Silva Daniela , de Azevedo Santos Lucas , Hamlin Trevor A. , Fonseca Guerra Célia , Freitas Matheus P. , Bickelhaupt F. Matthias
Published: February 2021

We have quantum chemically investigated the rotational isomerism of 1,2‐dihaloethanes XCH2CH2X (X = F, Cl, Br, I) at ZORA‐BP86‐D3(BJ)/QZ4P. Our Kohn‐Sham molecular orbital (KS‐MO) analyses reveal that hyperconjugative orbital interactions favor the gauche conformation in all cases (X = F−I), not only for X = F as in the current model of this so‐called gauche effect. We show that, instead, it is the interplay of hyperconjugation with Pauli repulsion between lone‐pair‐type orbitals on the halogen substituents that constitutes the causal mechanism for the gauche effect. Thus, only in the case of the relatively small fluorine atoms, steric Pauli repulsion is too weak to overrule the gauche preference of the hyperconjugative orbital interactions. For the larger halogens, X⋅⋅⋅X steric Pauli repulsion becomes sufficiently destabilizing to shift the energetic preference from gauche to anti, despite the opposite preference of hyperconjugation.
Sharp Turns and Fluorescent Repeats: Modular Construction and Shape‐Dependent Electronic Properties of π‐Conjugated Chain Molecules
Authors: Lee Milim , Kang Suk‐il , Song Sungmin , Kim Hongsik , Lee Dongwhan
Published: February 2021

In search of the design rules for structural ordering of open‐chain molecules, we have built a series of zig‐zag shaped π‐conjugated structures with ring‐fused heteroaromatics as sharp turns and tolane‐based linear fragments as light‐emitting units. Using only a finite number of common building blocks, an efficient “double‐elongation” strategy was implemented to construct a series of π‐conjugated oligomers with precise length control (55–89 % yields). Our approach takes advantage of the modular nature of the bis(triazolo)benzene synthesis and the masked reactivity of the nitro group. A combination of photophysical and DFT computational studies revealed that the bis(triazolo)benzene–tolane repeat units behave as electronically decoupled light‐absorbing/emitting units (λmax,em = 408–422 nm; ΦF = 20–25 % in THF). Such context‐independent photophysical properties promise their potential applications in chemical sensing and switching.
Neglecting Plasma Protein Binding in COVID‐19 Patients Leads to a Wrong Interpretation of Lopinavir Overexposure
Authors: Stanke‐Labesque Francoise , Concordet Didier , Djerada Zoubir , Bouchet Stéphane , Solas Caroline , Mériglier Etienne , Bonnet Fabrice , Mourvillier Bruno , Ruiz Stéphanie , Martin‐Blondel Guillaume , Epaulard Olivier , Schwebel Carole , Gautier‐Veyret Elodie , Gandia Peggy
Published: February 2021

Boffito et al. recalled the critical importance to correctly interpret protein binding. Changes of lopinavir pharmacokinetics in coronavirus disease 2019 (COVID‐19) are a perfect illustration. Indeed, several studies described that total lopinavir plasma concentrations were considerably higher in patients with severe COVID‐19 than those reported in patients with HIV. These findings have led to a reduction of the dose of lopinavir in some patients, hypothesizing an inhibitory effect of inflammation on lopinavir metabolism. Unfortunately, changes in plasma protein binding were never investigated. We performed a retrospective cohort study. Data were collected from the medical records of patients hospitalized for COVID‐19 treated with lopinavir/ritonavir in intensive care units or infectious disease departments of Toulouse University Hospital (France). Total and unbound concentrations of lopinavir, C reactive protein, albumin, and alpha‐1‐acid glycoprotein (AAG) levels were measured during routine care on the same samples. In patients with COVID‐19, increased total lopinavir concentration is the result of an increased AAG‐bound lopinavir concentration, whereas the unbound concentration remains constant, and insufficient to reduce the severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) viral load. Although international guidelines have recently recommended against using lopinavir/ritonavir to treat severe COVID‐19, the description of lopinavir pharmacokinetics changes in COVID‐19 is a textbook case of the high risk of misinterpretation of a total drug exposure when changes in protein binding are not taken into consideration.
An improved control strategy of grid‐tied solar photovoltaic system using active current detection method
Authors: Jalan Subham Kumar , Babu B. Chitti , Sridharan K. , Gupta Nitin
Published: February 2021

This paper presents an active current detection method (ACDM) for three‐phase grid‐tied solar photovoltaic (PV) system. The proposed control utilizes the character triangular function (CTF) for fundamental component extraction and minimizes the computational burden. This shows the effectiveness of proposed ACDM under variety of operating conditions. Moreover, the design of control algorithm allows superior voltage regulation in outer voltage control loop, which reduces the peak overshoot during transients. This will also help in regulating grid current quickly, and it accurately follows the reference current. Further, the proposed control algorithm effectively deals with several power quality (PQ) issues and maintains the continuous power flow to satisfy the load demand. Finally, the withstand capability of the proposed ACDM controller is verified by simulation studies under MATLAB®/Simulink environment and experimentally validated by dSPACE‐1104 based downscaled laboratory prototype.
Understanding cell‐cell communication and signaling in the colorectal cancer microenvironment
Authors: AlMusawi Shaikha , Ahmed Mehreen , Nateri Abdolrahman S.
Published: February 2021

Carcinomas are complex heterocellular systems containing epithelial cancer cells, stromal fibroblasts, and multiple immune cell‐types. Cell‐cell communication between these tumor microenvironments (TME) and cells drives cancer progression and influences response to existing therapies. In order to provide better treatments for patients, we must understand how various cell‐types collaborate within the TME to drive cancer and consider the multiple signals present between and within different cancer types. To investigate how tissues function, we need a model to measure both how signals are transferred between cells and how that information is processed within cells. The interplay of collaboration between different cell‐types requires cell‐cell communication. This article aims to review the current in vitro and in vivo mono‐cellular and multi‐cellular cultures models of colorectal cancer (CRC), and to explore how they can be used for single‐cell multi‐omics approaches for isolating multiple types of molecules from a single‐cell required for cell‐cell communication to distinguish cancer cells from normal cells. Integrating the existing single‐cell signaling measurements and models, and through understanding the cell identity and how different cell types communicate, will help predict drug sensitivities in tumor cells and between‐ and within‐patients responses.
Deep learning‐enabled imaging flow cytometry for high‐speedCryptosporidium and Giardia detection
Authors: Luo Shaobo , Nguyen Kim Truc , Nguyen Binh T. T. , Feng Shilun , Shi Yuzhi , Elsayed Ahmed , Zhang Yi , Zhou Xiaohong , Wen Bihan , Chierchia Giovanni , Talbot Hugues , Bourouina Tarik , Jiang Xudong , Liu Ai Qun
Published: February 2021

Imaging flow cytometry has become a popular technology for bioparticle image analysis because of its capability of capturing thousands of images per second. Nevertheless, the vast number of images generated by imaging flow cytometry imposes great challenges for data analysis especially when the species have similar morphologies. In this work, we report a deep learning‐enabled high‐throughput system for predicting Cryptosporidium and Giardia in drinking water. This system combines imaging flow cytometry and an efficient artificial neural network called MCellNet, which achieves a classification accuracy >99.6%. The system can detect Cryptosporidium and Giardia with a sensitivity of 97.37% and a specificity of 99.95%. The high‐speed analysis reaches 346 frames per second, outperforming the state‐of‐the‐art deep learning algorithm MobileNetV2 in speed (251 frames per second) with a comparable classification accuracy. The reported system empowers rapid, accurate, and high throughput bioparticle detection in clinical diagnostics, environmental monitoring and other potential biosensing applications.
On the unified error performance of PSK modulation schemes over mm‐wave wireless channels affected by carrier phase synchronization errors
Authors: Khanna Himanshu
Published: February 2021

The performance of radio‐frequency (RF) networks where channels are modeled by an extended‐generalized‐K(EGK) distribution and consider significant phase errors during coherent detection at the receiver due to carrier‐phase‐synchronization‐mismatch is investigated in this work. The performance is evaluated for a single‐hop link and two‐hop amplify‐and‐forward (AF) and decode‐and‐forward (DF) relay‐assisted RF links. The EGK is a generalized distribution, which can model various fading conditions in millimeter (mm)‐wave wireless channels where transmission frequency is 60 GHz and above and takes into account non‐homogeneous propagation, interference effects in a multiuser transmission environment, multipath fading and shadowing effects. The average symbol error probability (ASEP) performance is evaluated for a single‐hop link when carrier is modulated using multilevel PSK modulation scheme. Based on the analytical results obtained for a single‐hop link, the mathematical analysis for the error performance in widely employed AF and DF relay‐assisted RF two‐hop networks is developed and ASEP is derived. To quantify the degradation in system performance introduced by phase errors, the reference‐carrier phase estimation loss for a single‐hop RF link is also evaluated. The obtained analytical results are also verified by numerical plots and depict the effects of various channel conditions existing over the RF link and phase synchronization errors.
Architecture and sequence stratigraphy of the Upper Coralline Limestone formation, Malta—Implications for Eastern Mediterranean restriction prior to the Messinian Salinity Crisis
Authors: Bialik Or M. , Zammit Raymond , Micallef Aaron
Published: February 2021

The Eastern and Western Mediterranean are separated by an elevated plateau that regulates water exchange between these two basins. The Maltese archipelago, situated atop this topographic high, offers a unique window into the evolution of this plateau in the lead up to the Messinian Salinity Crisis. The Upper Coralline Limestone Formation was deposited between the late Tortonian and the early Messinian and was probably terminated by palaeoceanographic events related to the Messinian Salinity Crisis. It represents the youngest Miocene sedimentary deposits outcropping in the Maltese archipelago. This shallow‐water carbonate unit can be used to trace palaeoenvironmental changes atop the sill between the Eastern and Western Mediterranean and to explain the possible water flow restrictions to the Eastern Mediterranean that could have preceded the Messinian Salinity Crisis. Here field surveys, and analysis of the depositional environment within the Upper Coralline Limestone in Malta, are combined with recently acquired multichannel seismic reflection profiles between Malta and Gozo, to reconstruct the depositional sequence in the Malta Plateau during the late Miocene. The Upper Coralline Limestone consists of multiple coralline and larger benthic foraminifera dominated facies, extending from subtidal to intertidal environments. These accumulated in two depositional cycles observed in both outcrop and seismic reflection data. Each cycle exhibits an early aggradation–progradation phase followed by a progradation phase and a final aggradation phase. These manifest themselves in the outcrops as shallowing and deepening upwards phases. These were deposited above a deep water unit and are indicative of a preceding uplift phase followed by filling of the accommodation space through the deposition of the Upper Coralline Limestone Formation in shallow marine depths. The presence of this highly elevated sill during the late Miocene could have restricted circulation to the eastern basin.
Grazing affects vegetation diversity and heterogeneity in California vernal pools
Authors: Michaels Julia , Batzer Evan , Harrison Susan , Eviner Valerie T.
Published: February 2021

Disturbance often increases local‐scale (α) diversity by suppressing dominant competitors. However, widespread disturbances may also reduce biotic heterogeneity (β diversity) by making the identities and abundances of species more similar among patches. Landscape‐scale (γ) diversity may also decline if disturbance‐sensitive species are lost. California’s vernal pool plant communities are species rich, in part because of two scales of β diversity: (1) within pools, as species composition changes with depth (referred to here asvertical β diversity), and (2) between pools, in response to dispersal limitation and variation in pool attributes (referred to here ashorizontal β diversity). We asked how grazing by livestock, a common management practice, affects vernal pool plant diversity at multiple hierarchical spatial scales. In terms of abundance‐weighted diversity, grazing increased α both within local pool habitat zones and at the whole‐pool scale, as well as γ at the pasture scale without influencing horizontal or vertical β diversity. In terms of species richness, increases in α diversity within habitat zones and within whole pools led to small decreases in horizontal β diversity as species occupancy increased. This had a dampened effect on species richness at the γ (pasture) scale without any loss of disturbance‐sensitive species. We conclude that grazing increases species richness and evenness (α) by reducing competitive dominance, without large disruptions to the critical spatial heterogeneity (β) that generates high landscape‐level diversity (γ).
Lysosome Specific Platinum(II) Catecholates with Photoactive BODIPY for Imaging and Photodynamic Therapy in Near‐IR Light
Authors: Ramu Vanitha , Kundu Paramita , Upadhyay Aarti , Kondaiah Paturu , Chakravarty Akhil R.
Published: February 2021

Platinum(II)‐BODIPY (boron‐dipyrromethene) complexes of 1,2‐diaminocyclohexane (dach), [Pt(dach)(ML)] (MP) and [Pt(dach)(IML)] (IMP), where H2ML is morpholine‐appended O,O‐donor mono‐styryl BODIPY‐appended catecholate and H2IML is di‐iodinated morpholine‐conjugated O,O‐donor mono‐styryl BODIPY linked catecholate, were prepared for photodynamic therapy in near‐IR light (600–720 nm) by targeting lysosomes. Complex MP exhibited a band at 596 nm (ϵ=2.9×104 M−1 cm−1) and IMP at 710 nm (ϵ=2.6×104 M−1 cm−1) within PDT window in dimethyl sulfoxide (10 %)/Dulbecco's Modified Eagle's Medium (DMSO/DMEM, pH 7.2). Complexes MP and IMP showed red emission (λem) at 615 nm (λex=580 nm, ΦF=0.04) and 718 nm (λex=685 nm) (ΦF, fluorescence quantum yield) in DMSO (10 %)‐DMEM (pH 7.2). Emissive complex MP showed lysosome‐specific localization in cellular imaging study. Complex IMP showed photocytotoxicity in near‐IR light of 600–720 nm (IC50: 0.86–1.2 μM) with apoptotic cell death forming singlet oxygen in a type‐II pathway.