bluuebunny/crossref_metadata_2025_split huggingface dataset:
PBI/Clinoptilolite mixed‐matrix membranes for binary (N2/CH4) and ternary (CO2/N2/CH4) mixed gas separation
Authors: Montes Luna Angel de J. , Fuentes López Nidia C. , Castruita de León Griselda , Pérez Camacho Odilia , Yeverino Miranda Claudia Y. , Perera Mercado Yibran A. 
Published: November 2020

AbstractIn this work, polybenzimidazole (PBI)‐based mixed matrix membranes (MMMs) with natural zeolite were prepared and their transport properties for binary (N2/CH4) and ternary (CO2/N2/CH4) mixed‐gas separation were studied. The MMMs, were prepared with PBI as polymeric matrix and Mexican natural zeolite clinoptilolite enriched with cations of Ca2+ as filler. The thermal properties analysis of the PBI and MMMs studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) indicates that the MMMs membranes have Tg higher than 350°C and decomposition temperatures above 600°C compared with the pristine membranes. PBI membrane and MMMs were analyzed by X‐Ray Diffraction (XRD) and the diffraction patterns showed the zeolite signals combine with the amorphous dome from the polymeric matrix. In addition, the perm‐selectivity properties of the polymeric membranes and MMMs were tested with binary (N2/CH4; 10/90 mol%) and ternary (CO2/N2/CH4; 5/10/85 mol%) gas mixtures at different pressure rates (50, 150 and 300 psi). The perm‐selectivity properties of the MMMs membranes show an improvement in their values about 30% higher compared to the PBI polymeric membranes, favoring the permeation of CO2 and N2.
Optimizing crystallinity of engineered poly(lactic acid)/poly(butylene succinate) blends: The role of single and multiple nucleating agents
Authors: Barletta Massimiliano , Pizzi Elisa 
Published: November 2020

AbstractThis work deals with the design and experimental development of formulations based on bioplastic materials optimized for the production processes of high‐performance packaging products, suitable for food contact and characterized by high thermo‐mechanical stability. For this purpose, mixtures of poly (L‐lactic acid) (PLLA)/poly (butylene succinate) (PBS) (PLA/PBS) containing micro‐lamellar talc as reinforcing agent and inorganic nucleating agent have been obtained on a pre‐industrial scale. Through the addition in formulation of two organic nucleating agents, ethylene (bis)stereamide (EBS) and poly (D‐lactic acid) (PDLA), evaluated separately and in combination with each other, four different PLA/PBS formulations were produced by means of a co‐rotating twin screw extruder. The effects on the crystallinity of the materials obtained first in the form of pre‐dried pellets, then in the form of films by casting extrusion and, finally, as thermoformed items were compared, according to the variation of the chosen nucleation system. The effect on the crystallinity of the materials was assessed by differential scanning calorimetry (DSC) and by Fourier transform infrared analysis in attenuated total reflection mode (ATR‐FTIR). This approach aims to provide data for the further investigation on the processability and the thermo‐mechanical properties of end‐goods achievable by converting processes (melt processing) of the bioplastic compounds.
Tensile properties and corrosion resistance of PCL‐based 3D printed composites
Authors: Chen Bicheng , Wang Yiyang , Tuo Xiaohang , Gong Yumei , Guo Jing 
Published: November 2020

AbstractThe practicality of implantable biomedical materials depends on the design of size and function to meet the needs of personal customization. This paper used fused deposition modeling 3D printing process to make composite materials, and studied the performance of 3D printed samples through different matrix molecular weights, print filling settings, additives, and their contents. Mechanical properties, thermal analysis, structural characterization, surface hydrophilicity, and functional verification of PCL‐based 3D printed composites were discussed. We found that 80% print filling and 10% SA addition could greatly improve the work of fracture of the tensile sample. Furthermore, the efficacy and content of CS was also verified and analyzed. These resulting information are helpful for structural design and functional matching of medical composites.
Managing PFAS: A North Carolina Utility Story
Authors: Vandermeyden Carel , Hagerty Vaughn 
Published: November 2020

Key TakeawaysComprehensive, year‐round sampling of Cape Fear Public Utility Authority's raw water for per‐ and polyfluoroalkyl substances (PFAS) justified the need for PFAS treatment in conjunction with improved upstream point source control.Site‐specific pilot testing of different PFAS treatment technologies should be conducted to help identify the most effective treatment solutions based on local conditions.Communication strategies should be based on transparency, willingness to engage customers, and consistent messages, along with public advocacy for vigilant, consistently applied regulation.
Detroit's Robust Full Lead Service Line Replacement Program
Authors: Smalley Samuel A. , Peckinpaugh Bryan 
Published: November 2020

Key TakeawaysIn 2018, the state of Michigan implemented a revised Lead and Copper Rule that required replacement of all existing lead service lines.Given Detroit's unique financial challenges, significant efforts were made to ensure swift compliance with new standards without the need to raise rates.Expert teams in Detroit developed standard operating procedures to ensure efficient processes that are successful and have broad customer acceptance and compliance.
Aquifer Storage and Recovery: Can an Updated Inventory Predict Future System Success?
Authors: Bloetscher Frederick , Sham Chi Ho , Ratick Samuel J. 
Published: November 2020

Key TakeawaysAquifer storage and recovery, or ASR, is used to provide a stored water source where water supplies are unreliable or to address future demand.A 2013 inventory of ASR systems was updated in 2019 to evaluate project parameters and determine which variables are best at predicting the success of future ASR projects.With a time frame of June 2013 through October 2019, the revised inventory and analysis included data on new ASR sites and existing sites whose status had changed.
Survival analysis for AdVerse events with VarYing follow‐up times (SAVVY): Rationale and statistical concept of a meta‐analytic study
Authors: Stegherr Regina , Beyersmann Jan , Jehl Valentine , Rufibach Kaspar , Leverkus Friedhelm , Schmoor Claudia , Friede Tim 
Published: November 2020

AbstractThe assessment of safety is an important aspect of the evaluation of new therapies in clinical trials, with analyses of adverse events being an essential part of this. Standard methods for the analysis of adverse events such as the incidence proportion, that is the number of patients with a specific adverse event out of all patients in the treatment groups, do not account for both varying follow‐up times and competing risks. Alternative approaches such as the Aalen–Johansen estimator of the cumulative incidence function have been suggested. Theoretical arguments and numerical evaluations support the application of these more advanced methodology, but as yet there is to our knowledge only insufficient empirical evidence whether these methods would lead to different conclusions in safety evaluations. The Survival analysis for AdVerse events with VarYing follow‐up times (SAVVY) project strives to close this gap in evidence by conducting a meta‐analytical study to assess the impact of the methodology on the conclusion of the safety assessment empirically. Here we present the rationale and statistical concept of the empirical study conducted as part of the SAVVY project. The statistical methods are presented in unified notation, and examples of their implementation in R and SAS are provided.
Quality Control Testing, Characterization and Critical Quality Attributes of Adeno‐Associated Virus Vectors Used for Human Gene Therapy
Authors: Wright J. Fraser 
Published: November 2020

AbstractFor adeno‐associated virus (AAV)‐based human gene therapy, challenges for the translation of promising research results to successful clinical development include optimization of vector design and manufacturing processes to ensure that vectors prepared for administration to human subjects have attributes consistent with safe and durable expression. This article briefly reviews quality control methods for routine testing and supplemental characterization of AAV vectors for investigational product development. The relationship of vector and manufacturing process design with product critical quality attributes is discussed.
CFD–DEM modelling of biofilm streamer oscillations and their cohesive failure in fluid flow
Authors: Xia Yuqing , Jayathilake Pahala G. , Li Bowen , Zuliani Paolo , Chen Jinju 
Published: November 2020

AbstractBiofilm streamer motion under different flow conditions is important for a wide range of industries. The existing work has largely focused on experimental characterisations of these streamers, which is often time‐consuming and expensive. To better understand the physics of biofilm streamer oscillation and their interactions in fluid flow, a computational fluid dynamics–discrete element method model has been developed. The model was used to study the flow‐induced oscillations and cohesive failure of single and multiple biofilm streamers. We have studied the effect of streamer length on the oscillation at varied flow rates. The predicted single biofilm streamer oscillations in various flow rates agreed well with experimental measurements. We have also investigated the effect of the spatial arrangement of streamers on interactions between two oscillating streamers in parallel and tandem arrangements. Furthermore, cohesive failure of streamers was studied in an accelerating fluid flow, which is important for slowing down biofilm‐induced clogging.
Survival trends and prognostic factors in patients with solitary plasmacytoma of bone: A population‐based study
Authors: Shen Xuxing , Liu Shu , Wu Chao , Wang Jing , Li Jianyong , Chen Lijuan 
Published: November 2020

AbstractSolitary plasmacytoma of bone (SPB) is a single, isolated plasmacytoma originated from the bone. The survival trends of patients with SPB in recent years remain unknown. And the prognostic system of SPB may also need to be refined. The 18 Surveillance, Epidemiology, and End Results (SEER) databases of the National Cancer Institute in the United States were used to extract data for this study. The third edition of the International Classification of Disease for Oncology (ICD‐O‐3) code 9731 was used to identify cases of SPB. For each case, factors including age at the time of diagnosis, sex, race, marital status, insurance status, primary sites of tumors, and the use of surgery were collected. The outcomes of patients with SPB were compared between two groups. And the prognostic impacts of baseline characteristics and use of surgery was studied. A total of 4103 (from 1976 to 2016) cases of SPB were identified. The median age was 65 years old. Patients in time period‐2 (2008–2016) show better survival as compared to those in time period‐1(1976–2007) (median overall survival: 88 months vs. 73 months, p = 0.0332). Age ≤ 65 years and being male were associated with better outcomes. The widowed individuals had significantly inferior survival and myeloma‐specific survival than the single, married, or divorced individuals (p values all <0.0001). Patients with lesions in bones of skull and face and associated joints had longer survival as compared with those with bone lesions in other sites (median overall survival: 107 months vs. 79 months, p = 0.0694). The use of surgery was significantly associated with improved survival (median survival: surgery performed 98 months vs. not performed 73 months, hazards ratio [HR]: 0.7623, 95% CI: 0.7009–0.8472; p < 0.0001) and myeloma‐specific survival (median myeloma‐specific survival: surgery 160.0 months vs. no surgery 143.0 months, HR: 0.8469, 95% CI: 0.7493–0.9572; p = 0.0078). Multivariable analysis revealed that surgery, marital status, and age were independent prognostic factors for overall survival in patients with SPB. The improvement in the survival of patients with SPB has been observed in recent years. And several potential prognostic factors were identified. Future prospective studies are warranted to explore the roles of novel agents, surgery, and systemic chemotherapy in the treatment of SPB.
The Power of Chemists Is in What They Can Learn, Not What They Already Know
Authors: Buonomo Joseph A. 
Published: November 2020

AbstractIn this viewpoint, the concepts that chemistry transcends the laboratory into the clinic and beyond is explored from the perspective of a single individual who began strictly within synthetic chemistry. They learned through their training that in reality, chemists are capable of anything, requiring mentorship, open discussion, and some frontend work to learn something new.
On the Use of Side‐Chain NMR Relaxation Data to Derive Structural and Dynamical Information on Proteins: A Case Study Using Hen Lysozyme
Authors: Smith Lorna J. , van Gunsteren Wilfred F. , Hansen Niels 
Published: November 2020

AbstractValues of
and
order parameters derived from NMR relaxation measurements on proteins cannot be used straightforwardly to determine protein structure because they cannot be related to a single protein structure, but are defined in terms of an average over a conformational ensemble. Molecular dynamics simulation can generate a conformational ensemble and thus can be used to restrain
and
order parameters towards experimentally derived target values
(exp) and
(exp). Application of
and
order‐parameter restraining MD simulation to bond vectors in 63 side chains of the protein hen egg white lysozyme using 51
(exp) target values and 28
(exp) target values shows that a conformational ensemble compatible with the experimentally derived data can be obtained by using this technique. It is observed that
order‐parameter restraining of C−H bonds in methyl groups is less reliable than
order‐parameter restraining because of the possibly less valid assumptions and approximations used to derive experimental
(exp) values from NMR relaxation measurements and the necessity to adopt the assumption of uniform rotational motion of methyl C−H bonds around their symmetry axis and of the independence of these motions from each other. The restrained simulations demonstrate that side chains on the protein surface are highly dynamic. Any hydrogen bonds they form and that appear in any of four different crystal structures, are fluctuating with short lifetimes in solution.
The Charged Linker Modulates the Conformations and Molecular Interactions of Hsp90
Authors: López Abraham , Elimelech Annika R. , Klimm Karolin , Sattler Michael 
Published: November 2020

AbstractThe molecular chaperone Hsp90 supports the functional activity of specific substrate proteins (clients). For client processing, the Hsp90 dimer undergoes a series of ATP‐driven conformational rearrangements. Flexible linkers connecting the three domains of Hsp90 are crucial to enable dynamic arrangements. The long charged linker connecting the N‐terminal (NTD) and middle (MD) domains exhibits additional functions in vitro and in vivo. The structural basis for these functions remains unclear. Here, we characterize the conformation and dynamics of the linker and NTD−MD domain interactions by NMR spectroscopy. Our results reveal two regions in the linker that are dynamic and exhibit secondary structure conformation. We show that these regions mediate transient interactions with strand β8 of the NTD. As a consequence, this strand detaches and exposes a hydrophobic surface patch, which enables binding to the p53 client. We propose that the charged linker plays an important regulatory role by coupling the Hsp90 NTD−MD arrangement with the accessibility of a client binding site on the NTD.
CYP154C5 Regioselectivity in Steroid Hydroxylation Explored by Substrate Modifications and Protein Engineering**
Authors: Bracco Paula , Wijma Hein J. , Nicolai Bastian , Buitrago Jhon Alexander Rodriguez , Klünemann Thomas , Vila Agustina , Schrepfer Patrick , Blankenfeldt Wulf , Janssen Dick B. , Schallmey Anett 
Published: November 2020

AbstractCYP154C5 from Nocardia farcinica is a P450 monooxygenase able to hydroxylate a range of steroids with high regio‐ and stereoselectivity at the 16α‐position. Using protein engineering and substrate modifications based on the crystal structure of CYP154C5, an altered regioselectivity of the enzyme in steroid hydroxylation had been achieved. Thus, conversion of progesterone by mutant CYP154C5 F92A resulted in formation of the corresponding 21‐hydroxylated product 11‐deoxycorticosterone in addition to 16α‐hydroxylation. Using MD simulation, this altered regioselectivity appeared to result from an alternative binding mode of the steroid in the active site of mutant F92A. MD simulation further suggested that the entrance of water to the active site caused higher uncoupling in this mutant. Moreover, exclusive 15α‐hydroxylation was observed for wild‐type CYP154C5 in the conversion of 5α‐androstan‐3‐one, lacking an oxy‐functional group at C17. Overall, our data give valuable insight into the structure–function relationship of this cytochrome P450 monooxygenase for steroid hydroxylation.
Peritoneal mesothelioma associated with bladder cancer and occupational exposure to asbestos: A case report
Authors: Brahim Dorra , Mechergui Najla , Ben Said Hanene , Cherif Dhouha , Ladhari Nizar , Youssef Imen 
Published: November 2020

AbstractMesothelioma is a rare tumor usually located on the pleura. In this typical location, it is closely linked to asbestos exposure. However, in other locations such as in peritoneal mesothelioma, the association to asbestos remains unusual.
Prediction and Tuning of the Defects in the Redox Catalysts: Ethylene Oxychlorination
Authors: Fenes Endre , Qi Yanying , Ma Hongfei , Zhu Jun , Wang Yalan , Rout Kumar R. , Fuglerud Terje , Piccinini Marco , Chen De 
Published: November 2020

AbstractThe defect plays a significant role in tuning the electronic structure of metal compounds such as oxides, chlorides, sulfides and nitrides, which is frequently used to explain the enhanced catalytic activity. However, the dynamic change of defect relating to the oxidation state change during the reaction is rarely addressed, and it is still not able to be appropriately predicted since the kinetic modeling of the redox reaction involving the in‐situ formation of defects is challenged by the dynamic evolution of the active sites and the complex kinetic phenomena. Here, for the first time, we present a general method to build a new kinetic model of the redox reaction cycle by combined kinetics of reduction‐ and oxidation steps to predict the time and spatially resolved formation of defects of solid catalysts and the reaction products in ethylene oxychlorination on CuCl2/Al2O3 catalyst. The defect concentration can be tuned by manipulating the relative rates of the reduction‐ and oxidation steps.
Metal‐organic frameworks‐derived novel nanostructured electrocatalysts for oxygen evolution reaction
Authors: Qin Xinyu , Kim Dongwon , Piao Yuanzhe 
Published: November 2020

AbstractEngineering cost‐effective catalysts with exceptional performance for the electrochemical oxygen evolution reaction (OER) remains crucial for the accelerated development of renewable energy techniques, and especially so, given the pivotal role of OER in water electrolysis. On the basis of the metal nodes (clusters) and organic linkers, metal‐organic frameworks (MOFs) and their derivatives are rapidly gaining ground in the fabrication of electrocatalysts, with promising catalytic activity and sound durability in OER, thanks to their controllable pore structures, abundant unsaturated active sites of metal ion, extensive specific surface area, as well as easily functionalized/modified surfaces. This review presents an in‐depth understanding of the established progress of MOFs‐derived materials for OER electrocatalysis. The material designing strategies of the pristine, monometallic, and multimetallic MOFs‐based catalysts are summarized to indicate the infinite possibilities of the morphology and the composition of MOF‐derived materials. While emphasis is laid on the essential features of MOF‐derived materials for the electrocatalysis of the corresponding reactions, insights about the applications in OER are discussed. Finally, this paper is concluded by presenting challenges and perspectives for MOF‐derived materials’ future applications in OER electrocatalysis.
Metal–Organic Framework‐Encapsulated CoCu Nanoparticles for the Selective Transfer Hydrogenation of Nitrobenzaldehydes: Engineering Active Armor by the Half‐Way Injection Method
Authors: Li Yang , Li Yu‐Nong , Zheng Jian‐wei , Dong Xiao‐yun , Guo Rong‐xiu , Wang Yi‐ming , Hu Ze‐nan , Ai Yongjian , Liang Qionglin , Sun Hong‐bin 
Published: November 2020

AbstractA novel armor‐type composite of metal–organic framework (MOF)‐encapsulated CoCu nanoparticles with a Fe3O4 core (Fe3O4@SiO2‐NH2‐CoCu@UiO‐66) has been designed and synthesized by the half‐way injection method, which successfully serves as an efficient and recyclable catalyst for the selective transfer hydrogenation. In this half‐way injection approach, the pre‐synthetic Fe3O4@SiO2‐NH2‐CoCu was injected into the UiO‐66 precursor solution halfway through the MOF budding period. The formed MOF armor could play a role of providing significant additional catalytic sites besides CoCu nanoparticles, protecting CoCu nanoparticles, and improving the catalyst stability, thus facilitating the selective transfer hydrogenation of nitrobenzaldehydes into corresponding nitrobenzyl alcohols in high selectivity (99 %) and conversion (99 %) rather than nitro group reduction products. Notably, this method achieves the precise assembly of a MOF‐encapsulated composite, and the ingenious combination of MOF and nanoparticles exhibits excellent catalytic performance in the selective hydrogen transfer reaction, implementing a “1+1>2” strategy in catalysis.
Chemical and Genetic Studies on the Formation of Pyrrolones During the Biosynthesis of Cytochalasans
Authors: Zhang Haili , Hantke Verena , Bruhnke Pia , Skellam Elizabeth J. , Cox Russell J. 
Published: November 2020

AbstractA key step during the biosynthesis of cytochalasans is a proposed Knoevenagel condensation to form the pyrrolone core, enabling the subsequent 4+2 cycloaddition reaction that results in the characteristic octahydroisoindolone motif of all cytochalasans. In this work, we investigate the role of the highly conserved α,β‐hydrolase enzymes PyiE and ORFZ during the biosynthesis of pyrichalasin H and the ACE1 metabolite, respectively, using gene knockout and complementation techniques. Using synthetic aldehyde models we demonstrate that the Knoevenagel condensation proceeds spontaneously but results in the 1,3‐dihydro‐2H‐pyrrol‐2‐one tautomer, rather than the required 1,5‐dihydro‐2H‐pyrrol‐2‐one tautomer. Taken together our results suggest that the α,β‐hydrolase enzymes are essential for first ring cyclisation, but the precise nature of the intermediates remains to be determined.