bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomaterials against Bone Infection
Authors: Vallet‐Regí María , Lozano Daniel , González Blanca , Izquierdo‐Barba Isabel
Published: May 2020

Chronic bone infection is considered as one of the most problematic biofilm‐related infections. Its recurrent and resistant nature, high morbidity, prolonged hospitalization, and costly medical care expenses have driven the efforts of the scientific community to develop new therapies to improve the standards used today. There is great debate on the management of this kind of infection in order to establish consistent and agreed guidelines in national health systems. The scientific research is oriented toward the design of anti‐infective biomaterials both for prevention and cure. The properties of these materials must be adapted to achieve better anti‐infective performance and good compatibility, which allow a good integration of the implant with the surrounding tissue. The objective of this review is to study in‐depth the antibacterial biomaterials and the strategies underlying them. In this sense, this manuscript focuses on antimicrobial coatings, including the new technological advances on surface modification; scaffolding design including multifunctional scaffolds with both antimicrobial and bone regeneration properties; and nanocarriers based on mesoporous silica nanoparticles with advanced properties (targeting and stimuli‐response capabilities).
Regulating the Interfacial Electronic Coupling of Fe2N via Orbital Steering for Hydrogen Evolution Catalysis
Authors: Wu Yishang , Cai Jinyan , Xie Yufang , Niu Shuwen , Zang Yipeng , Wu Shaoyang , Liu Yun , Lu Zheng , Fang Yanyan , Guan Yong , Zheng Xusheng , Zhu Junfa , Liu Xiaojing , Wang Gongming , Qian Yitai
Published: May 2020

The capability of manipulating the interfacial electronic coupling is the key to achieving on‐demand functionalities of catalysts. Herein, it is demonstrated that the electronic coupling of Fe2N can be effectively regulated for hydrogen evolution reaction (HER) catalysis by vacancy‐mediated orbital steering. Ex situ refined structural analysis reveals that the electronic and coordination states of Fe2N can be well manipulated by nitrogen vacancies, which impressively exhibit strong correlation with the catalytic activities. Theoretical studies further indicate that the nitrogen vacancy can uniquely steer the orbital orientation of the active sites to tailor the electronic coupling and thus benefit the surface adsorption capability. This work sheds light on the understanding of the catalytic mechanism in real systems and could contribute to revolutionizing the current catalyst design for HER and beyond.
Controlling Crystal Growth via an Autonomously Longitudinal Scaffold for Planar Perovskite Solar Cells
Authors: Duan Xiaopeng , Li Xiang , Tan Licheng , Huang Zengqi , Yang Jia , Liu Gengling , Lin Zhuojia , Chen Yiwang
Published: May 2020

Sequential deposition is certified as an effective technology to obtain high‐performance perovskite solar cells (PVSCs), which can be derivatized into large‐scale industrial production. However, dense lead iodide (PbI2) causes incomplete reaction and unsatisfactory solution utilization of perovskite in planar PVSCs without mesoporous titanium dioxide as a support. Here, a novel autonomously longitudinal scaffold constructed by the interspersion of in situ self‐polymerized methyl methacrylate (sMMA) in PbI2 is introduced to fabricate efficient PVSCs with excellent flexural endurance and environmental adaptability. By this strategy perovskite solution can be confined within an organic scaffold with vertical crystal growth promoted, effectively inhibiting exciton accumulation and recombination at grain boundaries. Additionally, sMMA cross‐linked perovskite network can release mechanical stress and occupy the main channels for ion migration and water/oxygen permeation to significantly improve operational stability, which opens up a new strategy for the commercial development of large‐area PVSCs in flexible electronics.
Giant Piezospintronic Effect in a Noncollinear Antiferromagnetic Metal
Authors: Guo Huixin , Feng Zexin , Yan Han , Liu Jiuzhao , Zhang Jia , Zhou Xiaorong , Qin Peixin , Cai Jialin , Zeng Zhongming , Zhang Xin , Wang Xiaoning , Chen Hongyu , Wu Haojiang , Jiang Chengbao , Liu Zhiqi
Published: May 2020

One of the main bottleneck issues for room‐temperature antiferromagnetic spintronic devices is the small signal read‐out owing to the limited anisotropic magnetoresistance in antiferromagnets. However, this could be overcome by either utilizing the Berry‐curvature‐induced anomalous Hall resistance in noncollinear antiferromagnets or establishing tunnel‐junction devices based on effective manipulation of antiferromagnetic spins. In this work, the giant piezoelectric strain modulation of the spin structure and the anomalous Hall resistance in a noncollinear antiferromagnetic metal—D019 hexagonal Mn3Ga—is demonstrated. Furthermore, tunnel‐junction devices are built with a diameter of 200 nm to amplify the maximum tunneling resistance ratio to more than 10% at room‐temperature, which thus implies significant potential of noncollinear antiferromagnets for large signal‐output and high‐density antiferromagnetic spintronic device applications.
Electronic‐ECM: A Permeable Microporous Elastomer for an Advanced Bio‐Integrated Continuous Sensing Platform
Authors: Brown Matthew S. , Mendoza Melissa , Chavoshnejad Poorya , Razavi Mir Jalil , Mahler Gretchen J. , Koh Ahyeon
Published: May 2020

Tissue interfaced electronics have become promising candidates for transcending beyond conventional diagnostic technology, enabling chronic, quantitative health monitoring possibilities; however, these systems have primarily relied on impenetrable materials that contribute to the mechanical and physical mismatch of bioelectronic interfaces. Inspired by the soft mechanics and physical architecture of the epidermal extracellular matrix, this study presents a 3D microporous, fibrous mesh of polydimethylsiloxane for epidermal electronics. The resulting elastic microfiber mat, exhibits a minimal mechanical footprint with analogous viscoelastic behavior, cytocompatibility, and biofluid‐permeable interface capable of small molecule, gas, and transdermal water diffusion. Electrocardiography electrodes heterogeneously integrate within the synthetic electronic‐extracellular matrix (e‐ECM) membrane and achieve chronic high resolution biopotential monitoring during typically debilitating environments (e.g., vigorous sweating) for conventional bioelectronics. The e‐ECM platform provides a substrate template for open‐mesh electronics, enabling advanced implementations in long‐term quantitative analysis monitoring for wearable and implantable devices.
Ultrathin Electromagnetic–Acoustic Amphibious Stealth Coats
Authors: Zhou Yi , Chen Jian , Chen Rui , Chen Wenjie , Fan Zheng , Ma Yungui
Published: May 2020

Radar and sonar technologies are generally used to detect objects in air space and water. In some cases, both technologies are involved in probing waterborne objects like submarines. However, the simultaneous stealth regarding these two detection methods is not well explored due to the difficulty in satisfying material properties for two different physical systems. In this work, an artificial ultrathin amphibious stealth coat with a minimum thickness less than 0.5 mm achieving free‐space microwave and underwater acoustic absorption is proposed and demonstrated. It is realized by combining an electromagnetic metasurface and an acoustic metasurface—a flexible printed circuit with multisized metal resonators and a polydimethylsiloxane film with multisized air cavities. These two alien metasurfaces are engineered with minimized disturbance to each other by controlling the thicknesses of the resonators as thin as possible. A free‐space microwave absorptivity over 80% in the 12.38–13.7 GHz region and an underwater acoustic reflectance less than 10% in the 80–160 kHz region are obtained experimentally. The current work may shed light on advanced stealth technologies of the free‐space microwaves and underwater acoustic waves.
High‐Contrast Polymorphic Luminogen Formed through Effect of Tiny Differences in Intermolecular Interactions on the Intramolecular Charge Transfer Process
Authors: Wang Kang , Xie Yujun , Liu Ming , Tao Wei , Zhang Hao , Huang Meidong , You Jinmao , Liu Ying , Li Yunliang , Li Zhen , Dong Yong Qiang
Published: May 2020

Polymorphic luminogens provide the opportunity to disclose relation between the packing patterns and performance of luminogen and facilitate design of high performance luminogens. However, the effect of intramolecular charge transfer (ICT) is seldom used to construct luminogens with polymorphs, though the ICT process is very sensitive to microenvironment. In this work, 2‐(3‐(diphenylamino)‐9H‐xanthen‐9‐ylidene)‐malononitrile (DPAXM, 1) with donor–acceptor structure exhibits high contrast polymorphism dependent emission due to the effect of tiny differences of intermolecular interactions on ICT process. Three crystals of 1 with nearly identical structures emit yellow, orange, and red light with sequentially decreased efficiency which is attributed to ICT process modulated by the tiny differences in intermolecular interactions. In addition to ground state study, excited state of the polymorphs is investigated by time‐resolved ultrafast transient mid‐IR spectroscopy and theoretical calculation. Nonemissive crystals of 1 can also be obtained. The modulation of ICT effect by intermolecular interactions may provide a reference for the molecular design of high‐performance luminogens.
Orthogonally Polarized Luminescence of Single Bismuth Phosphate Microcrystal Doped with Europium
Authors: Li Peng , Li Feng , Zhang Xiaoyu , Li Yiming , Luo Xiaoxuan , Wang Ruimin , Cai Yin , Zhang Yanpeng
Published: May 2020

Rare‐earth‐doped micro/nanocrystals are significant candidates for nanophotonic and quantum information elements. Nevertheless, the polarization of light emission, which serves as one of the most widely adopted optical information carriers, has been rarely studied in such micro/nanocrystals due to the random crystalline orientation of the ensemble cluster as grown. Herein the polarization‐resolved spectroscopy on a single europium‐doped bismuth phosphate (BiPO4:Eu) microcrystal is performed, and a series of partially linearly polarized emission in the visible spectrum is observed, which can be grouped into orthogonal pairs. Such emission features are well explained by a phenomenological model of group theory that gives rise to the existence of optical C2 axes induced by local symmetry breaking. Such a polarization detection provides a neat optical method to distinguish single micro/nanocrystals from clusters, and confirms the tunable polarization features by selecting the suitable single microcrystal and engineering its orientation of crystalline axis. The rare‐earth‐doped single micro/nanocrystals, with precise positioning technique realized, can promisingly serve as controllable polarization devices on integrated photonic circuits.
Lateral Electric‐Field‐Controlled Perpendicular Magnetic Anisotropy and Current‐Induced Magnetization Switching in Multiferroic Heterostructures
Authors: Wang Mengxi , Guo Qi , Xu Xiaoguang , Zhang Zeyu , Ren Zengyao , Zhu Libai , Meng Kangkang , Chen Jikun , Wu Yong , Miao Jun , Jiang Yong
Published: May 2020

A strain‐mediated perpendicular magnetic anisotropy (PMA) and current‐induced magnetization switching via spin–orbit torque (SOT) in PbMg1/3Nb2/3O3‐PbTiO3 (PMN‐PT)/Ta/Pt/Co/Pt ferromagnetic heterostructures are reported. It is found that the PMA changes regularly with the preloaded lateral electric field. The SOT‐based current‐induced magnetization switching also shows a reversible trend via applying a lateral electric field. Domain wall propagation driven by electric field is observed directly under a fixed perpendicular magnetic field by magnetic optical Kerr (MOKE) microscope. These behaviors can be attributed to the strain from the PMN‐PT substrates induced by the piezoelectric effect under electric field. Basing on the domain wall motion mechanism, repeatable resistance states of the Hall bar can be controlled by external electric field under a small auxiliary magnetic field, which enables the information recorded in the device can be programmed by voltage. This study provides a potential method to design the electric field controlled spintronic devices.
Boosting Polysulfide Redox Kinetics by Graphene‐Supported Ni Nanoparticles with Carbon Coating
Authors: Yu Zhuo , Wang Bingliang , Liao Xiaobin , Zhao Kangning , Yang Zhifang , Xia Fanjie , Sun Congli , Wang Zhuo , Fan Chaoying , Zhang Jingping , Wang Yonggang
Published: May 2020

Lithium–sulfur batteries have attracted extensive attention because of their high energy density. However, their application is still impeded by the inherent sluggish kinetics and solubility of intermediate products (i.e., polysulfides) of the sulfur cathode. Herein, graphene‐supported Ni nanoparticles with a carbon coating are fabricated by directly carbonizing a metal–organic framework/graphene oxide composite, which is then dispersed on a commercial glass fiber membrane to form a separator with electrocatalytic activity. In situ analysis and electrochemical investigation demonstrate that this modified separator can effectively suppress the shuttle effect and regulate the catalytic conversion of intercepted polysulfides, which is also confirmed by density functional theory calculations. It is found that Ni–C sites can chemically interact with polysulfides and stabilize the radical S3•− through NiS bonds to enable fast dynamic equilibrium with S62−, while Ni nanoparticles reduce the oxidation barrier of Li2S and accelerate ion/electron transport. As a result, the corresponding lithium–sulfur battery shows a high cycle stability (88% capacity retention over 100 cycles) even with a high sulfur mass loading of 8 mg cm−2 and lean electrolyte (6.25 µL mg−1). Surprisingly, benefitting from the improved kinetics, the battery can work well at −50 °C, which is rarely achieved by conventional Li–S batteries.
Both hepatitis A and hepatitis D infections may be associated with more advanced liver disease in patients with chronic hepatitis B
Authors: Wu Jer‐Wei , Tseng Tai‐Chung , Liu Chun‐Jen , Su Tung‐Hung , Liu Chen‐Hua , Chen Pei‐Jer , Chen Ding‐Shinn , Kao Jia‐Horng
Published: May 2020

Acute infection of hepatitis A virus (HAV) causes transient but varying degrees of liver damage. In contrast, hepatitis D virus (HDV) only infects patients with chronic hepatitis B virus (HBV) infection, which may cause chronic and persistent liver damage. We aimed to explore whether infection of both hepatotropic viruses was associated with worse outcomes in patients with chronic HBV infection in a case‐control study. We collected serum and clinical data from 456 patients with chronic HBV infection, including 160, 150, and 146 patients with hepatocellular carcinoma (HCC), cirrhosis and inactive carrier status, respectively. Serum HAV‐IgG and anti‐HDV were determined retrospectively and seroprevalence rates of both markers were compared among the groups with different clinical stages. In the inactive carrier group, 101 (69.18%) and 3 (2.05%) patients had exposure to HAV and HDV infection, respectively. We found higher seropositive rates of HAV‐IgG in cirrhosis (82.67%) and HCC (99.38%) groups, but not seropositive rates of anti‐HDV (4.67% and 3.75% for cirrhosis and HCC respectively). When combining cirrhosis and HCC groups as patients with advanced liver disease, both seropositive HAV‐IgG and anti‐HDV were associated with increased risks of advanced liver disease with odds ratio of 10.65 (95% CI [confidence interval]: 2.74‐41.41, P < .001) and 12.64 (95% CI: 2.14‐74.78, P = .005), respectively. In the case‐control study of patients with chronic HBV infection, both exposure to HAV or HDV infection might be associated with increased risks of cirrhosis and HCC development.
Behavior of partially hydrolyzed polyacrylamide/polyethyleneimine reinforced with coal fly ash for preformed particle hydrogels
Authors: Pereira Kaio A. B. , Pereira Kaique A. B. , Oliveira Priscila F. , Mansur Claudia R. E.
Published: May 2020

High water production and low oil recovery are attributable to reservoir heterogeneity, making extraction economically inefficient. To improve oil production, it is important to solve permeability issues, to allow a more uniform and efficient sweep. In recent years, several studies of preformed particle gel (PPG) have been performed reduce reservoir heterogeneity and enhance oil recovery. In this work, the effect of coal fly ash (CFA) on hydrolyzed polyacrylamide (PHPA) crosslinked with polyethyleneimine PPG were evaluated regarding thermal, rheological, and structural properties. The rheological results showed an increase in elastic behavior with the presence of CFA. Thermal analysis revealed degradation resistance of 271% with only 1.0% CFA. The swelling test proved that the presence of CFA supports the absorption of a brine solution. The results suggest a significant increase in properties assessed with small CFA contents due to a strong interaction between CFA and three‐dimensional polymer networks.
Aromatase inhibitors: Role in postmenopausal breast cancer
Authors: Kharb Rajeev , Haider Kashif , Neha Kumari , Yar Mohammad S.
Published: May 2020

Postmenopausal women are at high risk of developing breast cancer due to estrogen production in peripheral tissues of the body other than ovaries. Aromatase is present in breast tissue, leading to local estrogen production which can be inhibited by a variety of steroidal and nonsteroidal aromatase inhibitors. There are many aromatase inhibitors available in clinical practice like exemestane, formestane, anastrozole, letrozole, fadrozole, vorozole, and so forth, but the major challenge in anti‐breast cancer therapy is the toxicity associated with aromatase inhibitors, especially the steroidal class of drugs. It is, therefore, urgently required to develop novel anticancer drugs having better safety and efficacy for the treatment of breast cancer. This study highlights the aromatase inhibitors reported in the current literature as well as the recent advances in the management of breast cancer.
Acyclic, Linear Oligo‐meta‐phenylenes as Multipotent Base Materials for Highly Efficient Single‐layer Organic Light‐emitting Devices
Authors: Yoshii Asami , Onaka Yuzuka , Ikemoto Koki , Izumi Tomoo , Sato Sota , Kita Hiroshi , Taka Hideo , Isobe Hiroyuki
Published: May 2020

Oligo‐meta‐phenylenes have been designed and synthesized as multipotent base materials of single‐layer organic light‐emitting devices. Simple molecular structures of oligo‐meta‐phenylenes composed of linear phenylene arrays benefited from the wealth of modern reactions available for biaryl couplings and were concisely synthesized in a series. Structure‐performance relationship studies with the first seven congeners revealed key features important for the multipotent materials in single‐layer devices. As a result, highly efficient phosphorescent electroluminescence was made possible in a highly simplified device architecture comprising one‐region, single‐layer configurations. Detailed investigations with hole‐only devices disclosed that the hole mobility was effectively retarded by potent materials, which should facilitate hole/electron recombination for electroluminescence.
Minimal-access retroperitoneal pancreatic necrosectomy for infected necrotizing pancreatitis: a multicentre study of a step-up approach
Authors: Liu Z-W , Yang S-Z , Wang P-F , Feng J , He L , Du J-D , Xiao Y-Y , Jiao H-B , Zhou F-H , Song Q , Zhou M-T , Xin X-L , Chen J-Y , Ren W-Z , Lu S-C , Cai S-W , Dong J-H
Published: May 2020

Background

Various minimally invasive approaches have been described for infected necrotizing pancreatitis. This article describes a modified minimal-access retroperitoneal pancreatic necrosectomy (MARPN) procedure assisted by gas insufflation.

Methods

This retrospective, observational study documented patients who had undergone a step-up MARPN between 1 January 2010 and 31 December 2016. A minimum follow-up of 1 year was required for inclusion. The step-up approach involved percutaneous catheter drainage followed by the modified MARPN and necrosectomy. If more than one access site was needed it was categorized as complex MARPN.

Results

Of 212 patients with infected necrotizing pancreatitis, 164 (77·4 per cent) underwent a step-up approach. The median number of percutaneous catheter drains and MARPN procedures was 3 (range 1–7) and 1 (1–6) respectively. Ninety patients (54·9 per cent) underwent complex MARPN. For residual necrosis after MARPN, three patients (1·8 per cent) underwent sinus tract gastroscopy, and 11 (6·7 per cent) had sinography combined with a tube change. However, operations in 13 patients (7·9 per cent) required conversion to open surgery. Postoperative complications developed in 103 patients (62·8 per cent). The mortality rate was 6·1 per cent (10 deaths).

Conclusion

A step-up approach using a modified MARPN for infected necrotizing pancreatitis is a reasonable option.
The process of curricular integration and its effects on anatomical knowledge retention
Authors: Zhao Xian , Goldman Ellen , Banani Tara , Kline Kathleen , Brown Kirsten , Lee Juliet , Jurjus Rosalyn A.
Published: May 2020

Introduction

Integration has been recognized as an important aspect of medical education. After transitioning from a discipline‐specific to a systems‐based preclinical curriculum, we examined faculty perceptions of the integrated approach and also whether it would lead to better anatomy knowledge retention.

Methods

To understand faculty perspectives, we reviewed curricular materials, interviewed block directors, and observed educational sessions. We analyzed knowledge retention through a 27‐question anatomy test, comparing scores from the last class of the discipline‐based curriculum and the first two classes of the integrated curriculum.

Results

Planning integrated content involves purposeful ordering, is challenging for faculty, and requires additional resources. Evaluation of the integrated approach for anatomy content demonstrated a significant increase in knowledge retention (p = .012; 56.28% vs. 63.98% for old vs. new curriculum).

Conclusions

This study helps the understanding of what is required for curricular integration. Our anatomy evaluation results corroborated the view that contextually embedded information is easier to learn and retain.
MsrA Efflux Pump Inhibitory Activity of Piper cubeba L.f. and its Phytoconstituents against Staphylococcus aureus RN4220
Authors: Ahirrao Pallavi , Tambat Rushikesh , Chandal Nishtha , Mahey Nisha , Kamboj Anjoo , Jain Upendra K. , Singh Inder Pal , Jachak Sanjay M. , Nandanwar Hemraj S.
Published: May 2020

MsrA, an efflux pump belonging to ATP‐binding cassette (ABC) transporter family that conferred resistance to macrolides, was detected in Staphylococcus aureus strains. Herein, we report the isolation of phytoconstituents from Piper cubeba fruit methanol extract and investigated their efflux pump inhibitory potential against S. aureus MsrA pump. Four isolated compounds, viz. pellitorine, sesamin, piperic acid and tetrahydropiperine studied in combination with erythromycin in S. aureus RN4220, exhibited 2–8‐fold reduction in minimum inhibitory concentration (MIC) of erythromycin. Pellitorine and sesamin decreased MIC of erythromycin by 8‐fold. The real‐time fluorometry‐based efflux and accumulation studies of ethidium bromide (EtBr) on S. aureus RN4220 in the presence of these compounds showed reduced efflux and enhanced uptake, thus indicating inhibition of the efflux pump. Pellitorine showed significant post‐antibiotic effect of erythromycin. The results revealed that the primary mechanism of action of these compounds involves steady ATP production impairment.
A review of the chemopreventative and chemotherapeutic properties of the phytochemicals berberine, resveratrol and curcumin, and their influence on cell death via the pathways of apoptosis and autophagy
Authors: D'Arcy Mark Sean
Published: May 2020

Phytochemicals are a diverse group of compounds found in a variety of fruits, vegetables and herbs, and have been reported to possess a number of health benefits. Marketed as supplements by health food retailers, this group of naturally occurring compounds have been investigated for a number of years to determine if they possess any chemopreventative and/or chemotherapeutic benefits. In this comprehensive review, the phytochemicals resveratrol, berberine and curcumin will be discussed, with particular focus being given to their proposed anticancer applications. The purpose of this review is to help clarify whether there is any truth in the claims that are regularly made regarding the efficacy of these compounds. To this end, a number of significant studies that involved the use of these phytochemicals will be identified, discussed and evaluated, to determine if they show promise in the ongoing fight to reduce the incidence rates and severity of various cancers. Specifically, it is the aim of this review to present and discuss key studies performed over the last two decades using these compounds and to evaluate, compare and contrast their effectiveness as chemopreventatives and chemotherapeutics. This should provide the reader with an overarching picture of how these structurally similar phytochemicals might be used in both clinical and nonclinical settings, as a part of the ongoing effort by clinicians, to help to slow down the increasing rate of cancers observed over the last few decades.
Identification of Novel Unspecific Peroxygenase Chimeras and Unusual YfeX Axial Heme Ligand by a Versatile High‐Throughput GC‐MS Approach
Authors: Knorrscheidt Anja , Püllmann Pascal , Schell Eugen , Homann Dominik , Freier Erik , Weissenborn Martin J.
Published: May 2020

Catalyst discovery and development requires the screening of large reaction sets necessitating analytic methods with the potential for high‐throughput screening. These techniques often suffer from substrate dependency or the requirement of expert knowledge. Chromatographic techniques (GC/LC) can overcome these limitations but are generally hampered by long analysis time or the need for special equipment. The herein developed multiple injections in a single experimental run (MISER) GC‐MS technique allows a substrate independent 96‐well microtiter plate analysis within 60 min. This method can be applied to any laboratory equipped with a standard GC‐MS. With this concept novel, unspecific peroxygenase (UPO) chimeras, could be identified, consisting of subdomains from three different fungal UPO genes. The GC‐technique was additionally applied to evaluate an YfeX library in an E. coli whole‐cell system for the carbene‐transfer reaction on indole, which revealed the thus far unknown axial heme ligand tryptophan.
Impact of multilayering on the filtration performance of clean air filter media
Authors: Tucny Jean‐Michel , Vidal David , Drolet François , Bertrand François
Published: May 2020

Fibrous filter media are commonly used to remove airborne particles that are harmful to human health and the environment. Although filter media are often multilayered for various reasons, no systematic study of the impact of multilayering on filter media performance has been reported. In this paper, direct numerical simulations with the lattice Boltzmann method are used in order to shed light on the impact of multilayering on the performance of clean bimodal fibrous filter media in a Stokes flow regime. Virtual model clean filter media with up to eight layers and various fibre formulations are compared in terms of permeability or pressure drop, capture efficiency, and quality factor. A careful analysis of the results revealed that multilayering had no statistically significant impact on the performance of the clean filter media. At best, the impact of multilayering was similar to that of the inherent variability of such random structures. Fibre formulation was found to be a more efficient way of improving the performance of the filter media. Placing interlayered air gaps between fibrous layers also slightly improved the quality factor by facilitating the flow at the interfaces of the fibrous layers. These findings will guide future studies on the performance of multilayered filters with more complex flow conditions, such as those encountered with inertial or nanofibre‐made filter media and with the fouling of filter media.
Rectified Ion Transport in Ultra‐thin Membrane Governed by Outer Membrane Electric Double Layer
Authors: Zhang Zhenkun , Wang Chao , Lin Lingxin , Xu Mengyi , Wu Yichun , Cao Liuxuan
Published: May 2020

Summary of main observation and conclusion

The outstanding combination of selectivity and permeability observed in ultra‐thin nanoporous membranes attracts broad interest from both fundamental research and practical application aspects. It is reported that the asymmetrical ion transport can be realized through the modification of polyelectrolytes on the outer membranes surface. However, the related mechanisms are still unclear which hinders their applications. Herein, we systematically investigate the origin of the ion current rectification in heterogeneously charged ultra‐thin nanopores. The calculated results based on the continuity model suggest that, the ion transport across the ultra‐thin membrane is dominated by the charge on the outer membrane surface rather than the pore wall. The overlap of electric double layer outside the pore entrance is essential for the ion asymmetric transport. And it accordingly results in the fact that the ion concentration enrichment and depletion effect occurring outside the nanopore orifices governs the high and low ionic conductance states under the applied bias. These features can be regulated by the membrane surface state, which is truly attractive because the surfaces of the outer membrane can be easily modified by experimental approaches. These findings provide the renew inspiration for the design of high‐performance 2D nanofluidic devices.
Fabrication of Carboxymethyl Chitosan Nanoparticles to Deliver Paclitaxel for Melanoma Treatment
Authors: Moghaddam Abolfazl Salehi , Khonakdar Hossein Ali , Sarikhani Einollah , Jafari Seyed Hassan , Javadi Azizeh , Shamsi Mohammad , Amirkhani Mohammad Amir , Ahadian Samad
Published: May 2020

In the present study, the effectiveness of paclitaxel nanocrystals (PTX NCs) encapsulated in carboxymethyl chitosan (CMCS) nanoparticles (CMCS−PTX NPs) as an anticancer drug is evaluated. The CMCS nanoparticles are produced via a cross‐junction microfluidic device where the PTX/CMCS concentration and flow rates in the device are optimized. The dynamic light scattering data show that the PTX NCs have a median diameter size of 230±90 nm, while the size of CMCS−PTX NPs is roughly 270±30 nm. The zeta‐potential result indicates less negative surface charge for the CMCS−PTX NPs as compared to the PTX NCs. Moreover, scanning electron microscopy micrographs, differential scanning calorimetry thermograms, and X‐ray diffraction patterns reveal that the physicochemical properties of the drug remain unaltered after perfusion through the microfluidic device. Cytotoxicity and cell endocytosis of PTX NCs and CMCS−PTX NPs are evaluated in vitro using G361 melanoma‐positive skin cells. The results reveal that the CMCS−PTX NPs increase the cellular uptake and cytotoxicity compared to the PTX NCs alone. In addition, the antitumor effect of CMCS−PTX NPs on B16 melanoma indicates the great potential of CMCS as a promising nano‐carrier for PTX NCs drug with potent inhibitory effect on the tumor growth.
One‐Step Fabrication of Perovskite‐Based Upconversion Devices
Authors: Wieghold Sarah , Bieber Alexander S. , Lackner Jens , Nienhaus Karin , Nienhaus G. Ulrich , Nienhaus Lea
Published: May 2020

Device fabrication methods for applications in upconversion processes using perovskite thin films have suffered from reproducibility and scalability issues, which prevent the upscaling of this technology. In this contribution, we developed a perovskite‐based upconversion device approach where the triplet annihilator is added in situ to the antisolvent and investigated the effect of the device fabrication procedure on the properties of our device. By comparing the properties of a device based on our new fabrication approach with the existing bilayer procedure, we seek to shed light on the underlying optoelectronic processes influenced by the different fabrication methods, while further advancing possible device architectures for upconversion devices. Device characterization by optical methods, X‐ray diffraction and atomic force microscopy revealed that the in situ fabricated devices match the performance or even outcompete our previously developed bilayer devices while significantly simplifying the device fabrication. In particular, we find that the developed one‐step fabrication technique enables intercalation of the upconverting layer into the perovskite film prior to annealing, resulting in a larger interface thus, more efficient charge extraction.
Product‐oriented Direct Cleavage of Chemical Linkages in Lignin
Authors: Shen Xiaojun , Xin Yu , Liu Huizhen , Han Buxing
Published: May 2020

Lignin is one of the most important biomacromolecules in the plant biomass and the largest renewable source of aromatic building blocks in nature. Selectively producing value‐added chemicals from the catalytic transformation of renewable lignin is of strategic significance and meet sustainability targets owing to the excessive consumption of non‐renewable petroleum resource, but remains a long‐term challenge owing to the complexity of lignin structure. This Minireview provides a summary and perspective of the extensive research that provides insight into selectively catalytic transformations of lignin and its derived monomers via directed scissor of chemical linkages (C−O and C−C bonds) with product‐oriented targets. Furthermore, some challenges and opportunities of lignin catalytic transformation are provided based on existing problems in this field for readers to discuss future research directions.
Phenotypic Analysis of the Mouse Hematopoietic Hierarchy Using Spectral Cytometry: From Stem Cell Subsets to Early Progenitor Compartments
Authors: Solomon Michael , DeLay Monica , Reynaud Damien
Published: May 2020

Phenotypic analysis by flow cytometry is one of the most utilized primary tools to study the hematopoietic system. Here, we present a complex panel designed for spectral flow cytometry that allows for the in‐depth analysis of the mouse hematopoietic stem and progenitor compartments. The developed panel encompasses the hematopoietic stem cell (HSC) compartment, an array of multipotent progenitors with early marks of lineage specification and a series of progenitors associated with lymphoid, granulo‐macrophagic, megakaryocytic and erythroid lineage commitment. It has a built‐in redundancy for key markers known to decipher the fine architecture of the HSC compartment by segregating subsets with different functional potential. As a resource, we used this panel to provide a snapshot view of the evolution of these phenotypically defined hematopoietic compartments during the life of the animals. We show that by using a spectral cytometer, this panel is compatible with the analysis of GFP‐expressing gene‐reporter mice across the hematopoietic system. We leverage this tool to determine how previously described markers such as CD150, CD34, CD105, CD41, ECPR, and CD49b define specific HSC subsets and confirm that high expression of the transcription factor Gfi1 is a hallmark of the most primitive HSC compartment. Altogether, our results provide a convenient protocol to obtain in one analysis a more extensive view of the hematopoietic architecture in mouse models. Our results could also serve as a base for further development of high‐end panels leveraging spectral flow cytometry beyond the 15‐fluorochrome panel presented in this report. © 2020 International Society for Advancement of Cytometry
Oceanic thermal structure mediates dive sequences in a foraging seabird
Authors: Meyer Xavier , MacIntosh Andrew J. J. , Chiaradia Andre , Kato Akiko , Ramírez Francisco , Sueur Cédric , Ropert‐Coudert Yan
Published: May 2020

Changes in marine ecosystems are easier to detect in upper‐level predators, like seabirds, which integrate trophic interactions throughout the food web.

Here, we examined whether diving parameters and complexity in the temporal organization of diving behavior of little penguins (Eudyptula minor) are influenced by sea surface temperature (SST), water stratification, and wind speed—three oceanographic features influencing prey abundance and distribution in the water column.

Using fractal time series analysis, we found that foraging complexity, expressed as the degree of long‐range correlations or memory in the dive series, was associated with SST and water stratification throughout the breeding season, but not with wind speed. Little penguins foraging in warmer/more‐stratified waters exhibited greater determinism (memory) in foraging sequences, likely as a response to prey aggregations near the thermocline. They also showed higher foraging efficiency, performed more dives and dove to shallower depths than those foraging in colder/less‐stratified waters.

Reductions in the long‐term memory of dive sequences, or in other words increases in behavioral stochasticity, may suggest different strategies concerning the exploration–exploitation trade‐off under contrasting environmental conditions.
Enhancement of extracellular bispecific anti‐MUC1 nanobody expression in E. coli BL21 (DE3) by optimization of temperature and carbon sources through an autoinduction condition
Authors: Rezaei Leila , Shojaosadati Seyed Abbas , Farahmand Leila , Moradi‐Kalbolandi Shima
Published: May 2020

Escherichia coli is one of the most suitable hosts for production of antibodies and antibody fragments. Antibody fragment secretion to the culture medium improves product purity in cell culture and diminishes downstream costs. In this study, E. coli strain BL21 (DE3) harboring gene encoding bispecific anti‐MUC1 nanobody was selected, and the autoinduction methodology for expression of bispecific anti‐MUC1 nanobody was investigated. Due to the replacement of IPTG by lactose as inducer, less impurity and toxicity in the final product were observed. To increase both intracellular and extracellular nanobody production, initially, the experiments were performed for the key factors including temperature and duration of protein expression. The highest amount of nanobody was produced after 21 h at 33°C. The effect of different carbon sources, glycerol, glucose, lactose, and glycine as a medium additive at optimum temperature and time were also assessed by using response surface methodology. The optimized concentrations of carbon sources were obtained as 0.75% (w/v), 0.03% (w/v), 0.1% (w/v), and 0.75% (w/v) for glycerol, glucose, lactose, and glycine, respectively. Finally, the production of nanobody in 2 L fermenter under the optimized autoinduction conditions was evaluated. The results show that the total titer of 87.66 µg/mL anti‐MUC1 nanobody, which is approximately seven times more than the total titer of nanobody produced in LB culture medium, is 12.23 µg/L .
Seasonal mixing from intermittent flow drives concentration‐discharge behaviour in a stream affected by coal mine drainage
Authors: Shaw Meaghan , Yazbek Lindsey , Singer David , Herndon Elizabeth
Published: May 2020

Abandoned mining operations continue to severely degrade many ecosystems worldwide by releasing acidic water and/or heavy metals into surface and groundwater. Contaminant concentrations in affected streams vary with discharge in patterns that reflect both geochemical reactions and variable mixing of contaminated and non‐contaminated waters. However, controls on concentration‐discharge (C‐Q) patterns remain unclear, particularly for constituents that experience changing solubility across redox and pH gradients. Understanding the C‐Q behaviour of contaminants aids in predicting both downstream transport and effects on aquatic life under variable flow. Here, we examined the C‐Q behaviours of non‐reactive (Na, K, Ca, Mg, Cl−) and reactive (Fe, Mn, Al, H+, SO42−) solutes in a stream contaminated with acid mine drainage in northeastern Ohio, USA. Concentration‐discharge patterns at the watershed outlet primarily reflected mixing of contaminated baseflow with intermittent inputs of high pH water draining from a passive limestone treatment system into the stream. The treatment system acted as an ephemeral tributary that mitigated contamination in the stream by diluting solutes, raising pH, and driving metal precipitation, but only when flow was present during wet seasons. Consequently, AMD‐derived reactive solutes (H+, Fe, Mn, Al) decreased with increasing stream discharge while relatively conservative solutes (e.g., Ca, Mg, K, Na) decreased only slightly or were chemostatic. This study highlights both the unique C‐Q patterns of reactive solutes when compared to those of non‐reactive solutes and the potential for intermittent streams to control C‐Q behaviour in headwater catchments.
Nonthyroidal second primary malignancies in differentiated thyroid cancer patients: Is the incidence increased comparing to the general population and could it be a radioiodine therapy consequence?
Authors: Cappagli Virginia , Caldarella Adele , Manneschi Gianfranco , Piaggi Paolo , Bottici Valeria , Agate Laura , Molinaro Eleonora , Bianchi Francesca , Elisei Rossella
Published: May 2020

The long‐term survival of differentiated thyroid cancer (DTC) patients and the need to perform several treatments with radioiodine (131‐I) lead to the question if the lifetime risk of developing a nonthyroidal second primary cancer (NTSPC) is increased in these patients. In our study, we assessed the prevalence of NTSPCs in thyroid cancer population and evaluated the possible causative role of 131‐I treatment. We analyzed 1096 consecutive patients followed at our institution from 1964 to 1998. A total of 101 NTSPCs were observed in 92/1096 patients (8.4%) among which 17/101 (16.8%) diagnosed before DTC and 84/101 (83.2%) diagnosed after. The most frequent tumor sites observed were breast and bladder/urinary tract in the post‐DTC group and breast and hematological system in the pre‐DTC group. Regarding 131‐I treatment, we did not observe any significant differences regarding either the number of treatments or the cumulative activity. The only significant parameter associated with an increased incidence of NTSPC was follow‐up (P = .02): a longer follow‐up period was associated with a higher number of NTSPCs. The mean latency between 131‐I and NTSPC was 10.52 ± 7.69 years. Comparing with the general Italian population, independent of radioiodine treatment, the standard incidence ratio in our cohort was similar to that of the general population (SIR 1.07) and this result was confirmed by analyzing only the treated group. In conclusion, these results show that the risk of NTSPCs in the DTC patients' population is similar to that in the general population and 131‐I treatment was not associated with an increased risk.
Biomolecular Simulation: A Perspective from High Performance Computing
Authors: Bolnykh Viacheslav , Rothlisberger Ursula , Carloni Paolo
Published: May 2020

High‐Performance Computing is impacting on all biomedical sciences, including molecular biophysics. Here, we describe general parallel computing strategies (multi‐threading and distributed computing) used in all the natural sciences, including molecular biophysics. Next, we describe how these strategies are applied in molecular dynamics simulations and enhanced sampling methods, either based on force fields, on density functional theory or on QM/MM potentials. As test cases, we focus on the widely used CPMD and GROMACS packages, along with a hybrid QM/MM interface coupling the two recently developed by a European team including the Authors. The review closes with a short perspective on the use of HPC‐based biomolecular simulations.

Additional information on optimizations and software adjustments to maximize code performance are provided in the Supporting Information.
Redox Potentials of High‐Valent Iron‐, Cobalt‐, and Nickel‐Oxido Complexes: Evidence for Exchange Enhanced Reactivity
Authors: Comba Peter , Löhr Anna‐Maria , Pfaff Florian , Ray Kallol
Published: May 2020

The ferrocene titration method has been employed to determine the one‐electron reduction potentials of a series of oxido‐iron(IV), oxido‐cobalt(IV) and oxido/hydroxido‐nickel(III) complexes based on the same tetradentate TMG3tren ligand (TMG3tren=tris[2‐(N‐tetramethylguanidyl)ethyl]amine). The S=2 ground state of the [(TMG3tren)FeIV=O]2+ complex allows an exchange enhanced reactivity, which enables it to perform efficient oxygen atom transfer (OAT) and hydrogen atom abstraction (HAA) reactions with a low one‐electron reduction potential of 270 mV vs. SCE. In the absence of exchange enhanced reactivity, the OAT and HAA abilities of the S=3/2 [(TMG3tren)CoIV−O(Sc(OTf)3)]2+, S=1/2 [(TMG3tren)NiIII−O(H)]2+ and the previously reported S=1 [(TMC)(CH3CN)FeIV=O]2+ and [(N4Py)FeIV=O]2+ complexes can be directly correlated to their reduction potentials. Notably, [(N4Py)FeIV=O]2+ and [(TMG3tren)FeIV=O]2+ exhibit similar OAT and HAA reactivities although the reduction potential of [(N4Py)FeIV=O]2+ is 0.24 V more positive than that of [(TMG3tren)FeIV=O]2+. The present study therefore provides experimental evidence for exchange enhanced reactivity and rationalizes nature's choice for employing S=2 oxido‐iron(IV) cores to achieve difficult oxidation reactions at biologically viable potentials.
A novel two‐band equilateral wavelet filter bank method for an automated detection of seizure from EEG signals
Authors: Ashokkumar S. R. , MohanBabu G. , Anupallavi S.
Published: May 2020

One can determinate the occurrence of epileptic seizure from the electroencephalogram (EEG) signal. Nonautomatic epilepsy detection is onerous and may be prone to error. They have augmented automated detection of seizure methods to attain accurate results. In view of this research work, we designed a frequency localized optimal filter bank to assess their effectiveness for automatic detection of seizures from EEG records. The basic preferred requirement of optimal filters relies on low bandwidth in the discipline of biomedical signal processing. This work provides a novel filter bank method called optimal equilateral wavelet filter bank (OEWFB) to satisfy the regularity criteria. This regularity constraint is being satisfied with semi‐definite programming (SDP) framework, which specifically does nothing with any parameterization. Implementing the proposed filter banks, it disbands EEG signals into five wavelet sub‐bands. The fuzzy entropy (FuEn), Renyi's entropy (ReEn), and the Kraskov entropy (KrEn) are being used for extracting the features from the wavelet sub‐bands. The P values provide the distinctive ability of the features. Classification with 10‐fold cross‐validation for several classifiers such as quadratic discriminant, linear quadratic discriminant, K‐nearest neighbor, support vector machine, logistic regression, and complex tree is utilized to classify the EEG signals into seizure vs non‐seizure class and seizure‐free vs seizure affected class. The proposed research work has gained the highest accuracy, specificity, sensitivity, and positive predictive values of 99.4%, 99%, 99.66%, and 99.35%, respectively, for class‐1 (ABCD vs E). The performances of the proposed work using the Bonn EEG data set ensure validation concerning compatibility and robustness.