bluuebunny/crossref_metadata_2025 huggingface dataset:
Population genetic structure of Texas horned lizards: implications for reintroduction and captive breeding
Authors: Williams Dean A. , Rains Nathan D. , Hale Amanda M.
Published: October 2019

The Texas horned lizard (Phrynosoma cornutum) inhabits much of the southern Great Plains of North America. Since the 1950s, this species has been extirpated from much of its eastern range and has suffered declines and local extinctions elsewhere, primarily due to habitat loss. Plans are underway to use captive breeding to produce large numbers of Texas horned lizards for reintroduction into areas that were historically occupied by this species and that currently have suitable habitat. We used mitochondrial markers and nuclear microsatellite markers to determine levels of genetic diversity and population structure in 542 Texas horned lizards sampled from across Texas and some neighboring states to help inform these efforts. Texas horned lizards still retain high genetic diversity in many parts of their current range. We found two highly divergent mitochondrial clades (eastern and western) and three major genetic groupings at nuclear microsatellite loci: a west group corresponding to the western mitochondrial clade and north and south groups within the eastern mitochondrial clade. We also found some evidence for human-mediated movement between these genetic clusters that is probably related to the historical importance of this species in the pet trade and as an iconic symbol of the southwestern United States. We do not know, however, if there are fitness costs associated with admixture (especially for the western and eastern clades) or if there are fitness costs to moving these lizards into habitats that are distinctly different from their ancestral areas. If present, either one or both of these fitness costs would decrease the effectiveness of reintroduction efforts. We therefore recommend that reintroduction efforts should maintain current genetic structure by restricting breeding to be between individuals within their respective genetic clusters, and by reintroducing individuals only into those areas that encompass their respective genetic clusters. This cautionary approach is based on the strong divergence between genetic groupings and their correspondence to different ecoregions.
Factors Affecting Adoption of Integrated Pest Management Technologies by Smallholder Common Bean Farmers in Kenya: A Case Study of Machakos and Bungoma Counties
Authors: Emongor Rosemary Akhungu , Uside Roselyne Juma
Published: October 2019

Common Bean is an important pulse crop in Kenya. The yields of common beans in Kenya have been low and declining. The decline in Common Bean yields has been due to biotic and abiotic stresses. Research was carried out to determine factors that influenced the adoption of Integrated Pests and Disease Management technologies in Bungoma and Machakos counties, Kenya. A multi-stage sampling procedure was used to randomly sample 502 smallholder farmers in Bungoma and Machakos counties. Primary data were collected from sampled farmers by carrying out face to face interviews using a structured questionnaire. Data were analyzed using descriptive statistics and Logistic regression using Statistical Package for Social Scientists (SPSS) version 20 Software. Descriptive statistics results showed that farmers in the two study sites used both modern and indigenous technical knowledge (ITK) to control pests and diseases on their bean crops and produce. The Logistic regression results showed that five factors significantly influenced the choice of IPM technologies by farmers. These were: region, level of education of the household head, access to extension services, household food security status and availability of markets for beans.  Access to extension and region were highly significant at 1% significance level. To achieve high yields the factor that significantly increased adoption of IPM in bean production such as access to extension should be enhanced.
Nutraceuticals: Formulations and Commercialization
Authors: Zaman Md Kamaruz , Milani Doniya N. , Bhatt Priyanka , Hariyadi Dewi Melani , Athiyah Umi , Islam Johirul , Pathak Yashwant V.
Published: October 2019

Nutraceuticals are currently growing alternative option for prevention as well as treatment for many acute and chronic illnesses. At some stage where a single pharmaceutical drug acts as a solo performer to treat the illness, the herbal remedy provides group of ingredients together to eradicate the disease. Many of the pharmaceutical drugs are from herbal origin and acts as a potent solo performer against the disease or disorder. While on the other side group of active ingredients present in herbal remedy may stimulate the effect of main active constituent to treat the disease. The resulting effect of course depends on how each of the ingredient are interacting with each other to stimulate the actions of each other. Though there is vast research going on development of nutraceuticals, the challenges associated with nutraceuticals such as variation in active ingredient content, difficulty in purification, lack of appropriate nomenclature, lack of confine regulations, formulation related challenges as well as solubility problems leads researchers as well as formulators in a direction to find out unmet need to overcome these challenges. The concept of solo and concert performance in regards to nutraceuticals and challenges related to nutraceuticals are described here in this article.
Impact of PDGF‐BB on cellular distribution and extracellular matrix in the healing rabbit Achilles tendon three weeks post‐operation
Authors: Meier Bürgisser Gabriella , Evrova Olivera , Calcagni Maurizio , Scalera Chiara , Giovanoli Pietro , Buschmann Johanna
Published: October 2019

Current methods for tendon rupture repair suffer from two main drawbacks: insufficient strength and adhesion formation, which lead to rerupture and impaired gliding. A novel polymer tube may help to overcome these problems by allowing growth factor delivery to the wound site and adhesion reduction, and by acting as a physical barrier to the surrounding tissue. In this study, we used a bilayered DegraPol® tube to deliver PDGF‐BB to the wound site in a full‐transection rabbit Achilles tendon model. We then performed histological and immunohistochemical analysis at 3 weeks postoperation. Sustained delivery of PDGF‐BB to the healing Achilles tendon led to a significantly more homogenous cell distribution within the healing tissue. Lower cell densities next to the implant material were determined for +PDGF‐BB samples compared to −PDGF‐BB. PDGF‐BB application increased proteoglycan content and reduced alpha‐SMA+ areas, clusters of different sizes, mainly vessels. Finally, PDGF‐BB reduced collagens I and III in the extracellular matrix. The sustained delivery of PDGF‐BB via an electrospun DegraPol® tube accelerated tendon wound healing by causing a more uniform cell distribution with higher proteoglycan content and less fibrotic tissue. Moreover, the application of this growth factor reduced collagen III and alpha‐SMA, indicating a faster and less fibrotic tendon healing.
Do Patients With Moderate or High Disease Activity Escalate Rheumatoid Arthritis Therapy According to Treat‐to‐Target Principles? Results From the Rheumatology Informatics System for Effectiveness Registry of the American College of Rheumatology
Authors: Yun Huifeng , Chen Lang , Xie Fenglong , Patel Himanshu , Boytsov Natalie , Zhang Xiang , Curtis Jeffrey R.
Published: October 2019

Objective

Despite strong recommendations for routine measurement of rheumatoid arthritis (RA) disease activity and associated treatment changes to attain remission/low disease activity, the measurement tools that clinicians use to evaluate RA patients’ disease activity and frequency of treatment change have not been well characterized. Therefore, we evaluated different measurement tools that physicians used to assess RA disease activity and associated RA treatment changes.

Methods

Using data from the Rheumatology Informatics System for Effectiveness (RISE) registry from January 2016 through June 2017, and using the following criteria: age ≥18 years, diagnosis of RA (International Classification of Diseases, Ninth and Tenth Revision, codes), ≥2 RISE visits, and ≥1 RA disease activity measure scored in 2016, we classified eligible patients’ drug use at the index visit as monotherapy or combination therapy with conventional synthetic (cs) and biologic disease‐modifying antirheumatic drugs (bDMARDs). Outcomes include change in treatment over 12 months. Mixed models identified factors associated with treatment change.

Results

Among 50,996 eligible patients, 27,274 had longitudinal data. The most commonly used measures were RAPID3 (78.9%) and the Clinical Disease Activity Index (CDAI) (34.2%). The frequency of treatment change during follow‐up was relatively low (35.6–54.6%), even for patients with moderate/high disease activity according to RAPID3 or CDAI scores. Older patients (age ≥75 years; adjusted odds ratio [ORadj] 0.63 [95% confidence interval (95% CI) 0.50–0.78]) and those already receiving combination therapy with csDMARDs (ORadj 0.45 [95% CI 0.33–0.61]) or combination therapy with bDMARDs (ORadj 0.30 [95% CI 0.24–0.38]) were less likely to change RA treatment even after multivariable adjustment.

Conclusion

Using the American College of Rheumatology's national RISE registry, one‐ to two‐thirds of RA patients failed to change their treatment, even when experiencing moderate/high disease activity. Multimodal interventions directed at both patients and providers are needed to encourage shared decision‐making, goal‐directed care, and to overcome barriers to treatment escalation.
Room‐Temperature AFM Electric‐Field‐Induced Topotactic Transformation between Perovskite and Brownmillerite SrFeOx with Sub‐Micrometer Spatial Resolution
Authors: Ferreiro‐Vila Elías , Blanco‐Canosa Santiago , Lucas del Pozo Irene , Vasili Hari Babu , Magén César , Ibarra Alfonso , Rubio‐Zuazo Juan , Castro Germán R. , Morellón Luis , Rivadulla Francisco
Published: October 2019

Reversible structural transformations between perovskite (PV) ABO3−δ and brownmillerite (BM) ABO2.5 (A = Ca2+, Sr2+; B = Fe4+/3, Co4+/3+) oxides can be induced by topotactic oxygen exchange at moderate temperatures under reducing/oxidizing conditions. The combination of a large oxide‐ion conductivity and a small free energy difference between the 4+/3+ oxidation states of many 3d transition metal ions enables these topotactic transformations. Herein, it is demonstrated that the electric field produced by a voltage‐biased atomic force microscopy tip can induce such transformation between PV SrFeO3−δ and BM SrFeO2.5 at room temperature and with sub‐micrometer spatial resolution. Interestingly, the structural transformation is kept after the electric field is removed, allowing a nonvolatile control of the local chemical, electrical, optical, and magnetic properties. Thus, the results presented in this paper open the door for the fabrication of stable ionic‐based devices through the electric field patterning of different crystallographic phases.
Electrodeposition Technologies for Li‐Based Batteries: New Frontiers of Energy Storage
Authors: Pu Jun , Shen Zihan , Zhong Chenglin , Zhou Qingwen , Liu Jinyun , Zhu Jia , Zhang Huigang
Published: October 2019

Electrodeposition induces material syntheses on conductive surfaces, distinguishing it from the widely used solid‐state technologies in Li‐based batteries. Electrodeposition drives uphill reactions by applying electric energy instead of heating. These features may enable electrodeposition to meet some needs for battery fabrication that conventional technologies can rarely achieve. The latest progress of electrodeposition technologies in Li‐based batteries is summarized. Each component of Li‐based batteries can be electrodeposited or synthesized with multiple methods. The advantages of electrodeposition are the main focus, and they are discussed in comparison with traditional technologies with the expectation to inspire innovations to build better Li‐based batteries. Electrodeposition coats conformal films on surfaces and can control the film thickness, providing an effective approach to enhancing battery performance. Engineering interfaces by electrodeposition can stabilize the solid electrolyte interphase (SEI) and strengthen the adhesion of active materials to substrates, thereby prolonging the battery longevity. Lastly, a perspective of future studies on electrodepositing batteries is provided. The significant merits of electrodeposition should greatly advance the development of Li‐based batteries.
Recent Progress of In Situ Transmission Electron Microscopy for Energy Materials
Authors: Zhang Chao , Firestein Konstantin L. , Fernando Joseph F. S. , Siriwardena Dumindu , von Treifeldt Joel E. , Golberg Dmitri
Published: October 2019

In situ transmission electron microscopy (TEM) is one of the most powerful approaches for revealing physical and chemical process dynamics at atomic resolutions. The most recent developments for in situ TEM techniques are summarized; in particular, how they enable visualization of various events, measure properties, and solve problems in the field of energy by revealing detailed mechanisms at the nanoscale. Related applications include rechargeable batteries such as Li‐ion, Na‐ion, Li–O2, Na–O2, Li–S, etc., fuel cells, thermoelectrics, photovoltaics, and photocatalysis. To promote various applications, the methods of introducing the in situ stimuli of heating, cooling, electrical biasing, light illumination, and liquid and gas environments are discussed. The progress of recent in situ TEM in energy applications should inspire future research on new energy materials in diverse energy‐related areas.
Carbon‐Based Nanocages: A New Platform for Advanced Energy Storage and Conversion
Authors: Wu Qiang , Yang Lijun , Wang Xizhang , Hu Zheng
Published: October 2019

Energy storage and conversion play a crucial role in modern energy systems, and the exploration of advanced electrode materials is vital but challenging. Carbon‐based nanocages consisting of sp2 carbon shells feature a hollow interior cavity with sub‐nanometer microchannels across the shells, high specific surface area with a defective outer surface, and tunable electronic structure, much different from the intensively studied nanocarbons such as carbon nanotubes and graphene. These structural and morphological characteristics make carbon‐based nanocages a new platform for advanced energy storage and conversion. Up‐to‐date synthetic strategies of carbon‐based nanocages, the utilization of their unique porous structure and morphology for the construction of composites with foreign active species, and their significant applications to the advanced energy storage and conversion are reviewed. Structure–performance correlations are discussed in depth to highlight the contribution of carbon‐based nanocages. The research challenges and trends are also envisaged for deepening and extending the study and application of this multifunctional material.
How Nanoparticles Transform Single Molecule Measurements into Quantitative Sensors
Authors: Wu Yanfang , Bennett Danielle , Tilley Richard D. , Gooding John Justin
Published: October 2019

Single molecule measurements are revolutionizing the understanding of the stochastics of behavior of single molecules. There is a common theme referred to as a near‐field approach, in how many single molecule measurements are being performed in assays. The term near field is used because the measurement volume is typically very small such that a single molecule, or a single molecule binding pair, within that volume is of an appreciable concentration. The next development in detection will be performing many single molecule measurements at one time such that single molecule measurements can be used as the basis for quantitative analysis. There have already been some notable developments in this direction. Again, all have a common theme in that nanoparticles are used to create many near‐field volumes that can be measured simultaneously. Herein, the coupled developments in nanoparticles and measurement strategies that allow nanoparticles to be the backbone of the next generation of sensing technologies are discussed.
Integrated Triboelectric Nanogenerators in the Era of the Internet of Things
Authors: Ahmed Abdelsalam , Hassan Islam , El‐Kady Maher F. , Radhi Ali , Jeong Chang Kyu , Selvaganapathy Ponnambalam Ravi , Zu Jean , Ren Shenqiang , Wang Qing , Kaner Richard B.
Published: October 2019

Since their debut in 2012, triboelectric nanogenerators (TENGs) have attained high performance in terms of both energy density and instantaneous conversion, reaching up to 500 W m−2 and 85%, respectively, synchronous with multiple energy sources and hybridized designs. Here, a comprehensive review of the design guidelines of TENGs, their performance, and their designs in the context of Internet of Things (IoT) applications is presented. The development stages of TENGs in large‐scale self‐powered systems and technological applications enabled by harvesting energy from water waves or wind energy sources are also reviewed. This self‐powered capability is essential considering that IoT applications should be capable of operation anywhere and anytime, supported by a network of energy harvesting systems in arbitrary environments. In addition, this review paper investigates the development of self‐charging power units (SCPUs), which can be realized by pairing TENGs with energy storage devices, such as batteries and capacitors. Consequently, different designs of power management circuits, supercapacitors, and batteries that can be integrated with TENG devices are also reviewed. Finally, the significant factors that need to be addressed when designing and optimizing TENG‐based systems for energy harvesting and self‐powered sensing applications are discussed.
Engineered Cardiac Pacemaker Nodes Created by TBX18 Gene Transfer Overcome Source–Sink Mismatch
Authors: Grijalva Sandra I. , Gu Jin‐mo , Li Jun , Fernandez Natasha , Fan Jinqi , Sung Jung Hoon , Lee Seung Yup , Herndon Conner , Buckley Erin M. , Park Sung‐Jin , Fenton Flavio H. , Cho Hee Cheol
Published: October 2019

Every heartbeat originates from a tiny tissue in the heart called the sinoatrial node (SAN). The SAN harbors only ≈10 000 cardiac pacemaker cells, initiating an electrical impulse that captures the entire heart, consisting of billions of cardiomyocytes for each cardiac contraction. How these rare cardiac pacemaker cells (the electrical source) can overcome the electrically hyperpolarizing and quiescent myocardium (the electrical sink) is incompletely understood. Due to the scarcity of native pacemaker cells, this concept of source–sink mismatch cannot be tested directly with live cardiac tissue constructs. By exploiting TBX18 induced pacemaker cells by somatic gene transfer, 3D cardiac pacemaker spheroids can be tissue‐engineered. The TBX18 induced pacemakers (sphTBX18) pace autonomously and drive the contraction of neighboring myocardium in vitro. TBX18 spheroids demonstrate the need for reduced electrical coupling and physical separation from the neighboring ventricular myocytes, successfully recapitulating a key design principle of the native SAN. β‐Adrenergic stimulation as well as electrical uncoupling significantly increase sphTBX18s' ability to pace‐and‐drive the neighboring myocardium. This model represents the first platform to test design principles of the SAN for mechanistic understanding and to better engineer biological pacemakers for therapeutic translation.
Predictions and Strategies Learned from Machine Learning to Develop High‐Performing Perovskite Solar Cells
Authors: Li Jinxin , Pradhan Basudev , Gaur Surya , Thomas Jayan
Published: October 2019

Perovskite solar cells (PSCs) have recently received considerable attention due to the high energy conversion efficiency achieved within a few years of their inception. However, a machine learning (ML) approach to guide the development of high‐performing PSCs is still lacking. In this paper ML is used to optimize material composition, develop design strategies, and predict the performance of PSCs. The ML models are developed using 333 data points selected from about 2000 peer reviewed publications. These models guide the design of new perovskite materials and the development of high‐performing solar cells. Based on ML guidance, new perovskite compositions are experimentally synthesized to test the practicability of the model. The ML model also shows its ability to predict underlying physical phenomena as well as the performance of PSCs. The PSC model matches well with the theoretical prediction by the Shockley and Queisser limit, which is almost impossible for a human to find from an ensemble of data points. Moreover, strategies for developing high‐performing PSCs with different bandgaps are also derived from the model. These findings show that ML is very promising not only for predicting the performance, but also for providing a deeper understanding of the physical phenomena associated with the PSCs.
Simultaneous effect of particle size and solid concentration on the hydrodynamics of slurry bubble column reactors
Authors: Lakhdissi El Mahdi , Soleimani Iman , Guy Christophe , Chaouki Jamal
Published: October 2019

The simultaneous effect of particle size and concentration on the total gas holdup of slurry bubble column reactors was investigated in this work. The total gas holdup was measured for air–water–glass beads systems. Three solid concentrations and three particle diameters were used. It was found that increasing particle size at high constant concentration decreases gas holdup. Moreover, increasing solid concentration decreases gas holdup and this decreasing effect is higher for larger particles. Also, solid particles have two effects on hydrodynamics, namely, changing the viscosity and density of the liquid phase as well as hindering the bubbles from rising within the column by the collision phenomenon. Therefore, a novel correcting factor was introduced to correct the gas holdup. The hindering factor considers both the collision efficiency affected by the particle size as well as the solid concentration. A novel correlation was developed to predict the experimental data of the three‐phase gas holdup.
A Braitenberg Vehicle Based on Memristive Neuromorphic Circuits
Authors: Wang Cong , Yang Zaizheng , Wang Shuang , Wang Pengfei , Wang Chen-Yu , Pan Chen , Cheng Bin , Liang Shi-Jun , Miao Feng
Published: October 2019

The Braitenberg vehicle as a simple conceptual model to characterize the response behaviors of animals or insects under a stimulus is widely used to develop autonomous vehicles able to adapt to the varying environments. Considerable effort has been devoted to building neuromorphic processors with the software in the vehicles; however, there has been no demonstration of Braitenberg vehicle with neuromorphic hardware so far. Herein, a Braitenberg vehicle with simple memristive neuromorphic circuits is built for the first time. This vehicle exhibits adaptive behaviors in the supervised learning process and is eventually trained to conduct the task of tracking path. Moreover, the memristive circuit in the vehicle demonstrates a very short response latency (≈56 ns) to input sensory information. Herein, an alternative promising solution to build self‐adaptive robots and pave the way for the realization of autonomous robots based on memristive neuromorphic circuits is offered.
Copper‐Catalyzed Sulfonyl Radical‐Enabled Regioselective Cyclization of 1,6‐Enynes
Authors: Zhang Jun‐Yao , Bao Wen‐Hui , Qin Fu‐Hua , Lei Ke‐Wei , Li Qiang , Wei Wen‐Ting
Published: October 2019

A copper‐catalyzed cascade cyclization of 1,6‐enynes with sulfonyl hydrazides for producing various sulfonyl‐substituted γ‐lactams is described. This sulfonyl radical‐enabled cyclization reaction features excellent regioselectivity, mild conditions and broad substrate scope, enabling the formation of new C−S and C−C bonds through radical sulfonylation, intramolecular cyclization and hydrogen abstraction. Moreover, relevant experiments have been carried out to probe a possible mechanism.
Endoscopic sinus surgery improves aspirin treatment response in aspirin‐exacerbated respiratory disease patients
Authors: Shah Sharan J. , Abuzeid Waleed M. , Ponduri Anusha , Pelletier Teresa , Ren Zhen , Keskin Taha , Roizen Gigia , Rosenstreich David , Ferastraoaru Denisa , Jerschow Elina
Published: October 2019

Background

Aspirin desensitization and treatment benefits most patients with aspirin‐exacerbated respiratory disease (AERD), although some patients fail therapy. Our objective was to assess whether recent endoscopic sinus surgery (ESS) improved aspirin treatment outcomes in AERD patients who initially failed aspirin therapy.

Methods

Outcomes of aspirin desensitization and treatment in AERD patients prospectively enrolled were assessed preoperatively and at 4, 12, and 24 weeks after ESS by determining changes in Asthma Control Test (ACT) and Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) scores and respiratory function. Biomarkers, including fractional excretion of nitric oxide (FeNO), spirometry, nasal inspiratory peak flow (NPF), immunoglobulin E (IgE), and eosinophil count, were measured.

Results

Nineteen patients who benefited (responders) and 21 patients who failed (nonresponders) preoperative aspirin treatment with a distant history of ESS (mean, 48 months) were identified. Nonresponders were more likely to be African American (71%, p < 0.01) and have higher baseline IgE levels (252 kU/L vs 87 kU/L in responders, p < 0.01). 24 of the 40 patients (nine responders and 15 non‐responders) required subsequent ESS and underwent another aspirin desensitization 3‐4 weeks after ESS. All 24 patients tolerated a second round of aspirin desensitization and treatment. The primary aspirin therapy was associated with a significant increase in IgE in nonresponders, but there was no significant increase in IgE after the second aspirin desensitization and treatment.

Conclusion

Antecedent ESS enhances aspirin treatment responses in AERD patients and may convert patients who failed aspirin treatment before surgery to a more responsive phenotype after ESS. Patients with higher baseline serum IgE levels may benefit from ESS performed shortly before aspirin desensitization and therapy.
A minimally invasive endoscopic transnasal retropterygoid approach to the upper parapharyngeal space: anatomic studies and surgical implications
Authors: Liu Juan , Sun Xicai , Liu Quan , Gu Yurong , Li Houyong , Zheng Chunquan , Wang Dehui , Fernandez‐Miranda Juan C. , Snyderman Carl H. , Yu Hongmeng
Published: October 2019

Background

Surgery remains the mainstay of treatment for lesions in the parapharyngeal space. However, gaining access to the parapharyngeal space is often challenging. In this study we aim to describe a minimally invasive technique of approaching the upper parapharyngeal space through an endoscopic transnasal retropterygoid approach, based on anatomic studies and surgeries.

Methods

Six fresh human cadaver heads were prepared for anatomic study at the Surgical Neuroanatomy Laboratory of the Center for Cranial Base Surgery within the Department of Neurological Surgery at the University of Pittsburgh School of Medicine. Three clinical cases seen in the Department of Otolaryngology, Eye, Ear, Nose, and Throat Hospital, Shanghai Medical College of Fudan University, were used to illustrate the technique and feasibility of this approach and to assess its indications, advantages, and drawbacks.

Results

The medial pterygoid plate is the primary landmark of the endoscopic transnasal retropterygoid approach to the upper parapharyngeal space. Access to the upper parapharyngeal space could be obtained by removing the mucosa on the medial pterygoid plate and the mucosa below the pharyngeal orifice of the Eustachian tube. The 3 patients in our study tolerated the procedure well and had no serious complications after surgery.

Conclusion

The anatomic data and clinical cases in this study confirm that an endoscopic transnasal retropterygoid approach is a feasible and effective surgical treatment for selected tumors in the upper parapharyngeal space.
Development and validation of a preclinical model for training and assessment of cerebrospinal fluid leak repair in endoscopic skull base surgery
Authors: Mattavelli Davide , Ferrari Marco , Rampinelli Vittorio , Schreiber Alberto , Buffoli Barbara , Deganello Alberto , Rodella Luigi F. , Fontanella Marco M. , Nicolai Piero , Doglietto Francesco
Published: October 2019

Background

Achieving an effective endoscopic skull base reconstruction in case of large dural defects requires specific training and can be extremely challenging. The aim of this study was to describe the development and validation of a preclinical model for cerebrospinal fluid (CSF) leak repair, which can be used for training and to test the mechanical efficacy of endoscopic skull base reconstruction.

Methods

Eleven fresh‐frozen cadaver heads were dissected. A catheter was inserted in the subdural space via a cervical access, which was sealed with mastic; a vertical graduated tube connected to the catheter measured intracranial pressure (ICP), while stained water was injected intracranially. After endoscopic skull base reconstruction was performed, an expert surgeon assessed its efficacy. ICP was then gradually increased until a leak was evident and CSF leak pressure value was recorded. The correlation between subjective and quantitative evaluations was investigated through Pearson and Spearman correlation tests.

Results

The model was successfully tested in 11 specimens. A single, large dural defect was created in each model (transplanum‐transtuberculum = 4; transplanum‐transtuberculum‐transsellar = 3; transclival = 3; transcribriform‐transplanum = 1). Skull base reconstruction always comprised a rigid buttress with temporal fascia and/or fat. The CSF leak pressure ranged from 4 to 110 cmH2O. The correlation between expert subjective and quantitative assessment of skull base reconstruction mechanical efficacy was high (r = 0.7; rs = 0.7; p = 0.010 and p = 0.006, respectively).

Conclusion

This preclinical model is simple, easily reproducible, and effective in simulating an intraoperative leak and objectively measures the CSF leak pressure point of a skull base reconstruction.
Oxysulfide Semiconductors for Photocatalytic Overall Water Splitting with Visible Light
Authors: Zhang Guigang , Wang Xinchen
Published: October 2019

Photocatalytic overall water splitting by sulfide‐based materials is a great challenge because of the poor resilience of such materials against hole oxidation. In a recent study, Domen and co‐workers developed an innovative strategy to stabilize sulfide‐based photocatalysts by hybridizing S 3p with O 2p orbitals to produce oxysulfides in which S2− is stable. Further surface engineering of the oxysulfides with dual co‐catalysts promoted charge separation and interface transfer, thus reducing the charge build‐up that inhibits photocorrosion. The pH value of the reaction mixture is a critical consideration for achieving efficient stoichiometric H2 and O2 evolution by these oxysulfide photocatalysts.
Asymmetric Synthesis of Chiral Sulfoximines through the S‐Alkylation of Sulfinamides
Authors: Aota Yusuke , Kano Taichi , Maruoka Keiji
Published: October 2019

Innovation in drug discovery critically depends on the development of new bioisosteric groups. Chiral sulfoximines, which contain a tetrasubstituted sulfur atom that bears one nitrogen, one oxygen, and two different carbon substituents, represent an emerging chiral bioisostere in medicinal chemistry. Chiral sulfoximines are conventionally prepared by a stereospecific nitrene transfer reaction to chiral sulfoxides; however, the number of readily available chiral sulfoxides remains limited. Herein, we report the asymmetric synthesis of a class of hitherto difficult‐to‐access chiral sulfoximines with two structurally similar alkyl chains. Our synthetic approach is based on the sulfur‐selective alkylation of easily accessible chiral sulfinamides with commercially available reagents under simple and safe conditions. This stereospecific S‐alkylation offers a general and scalable approach to the asymmetric synthesis of chiral sulfoximines, which represent important substructures in bioactive molecules.
Solid‐State and Gas‐Phase Structures and Energetic Properties of the Dangerous Methyl and Fluoromethyl Nitrates
Authors: Reichel Marco , Krumm Burkhard , Vishnevskiy Yury V. , Blomeyer Sebastian , Schwabedissen Jan , Stammler Hans‐Georg , Karaghiosoff Konstantin , Mitzel Norbert W.
Published: October 2019

An improved synthesis of the simplest nitric acid ester, methyl nitrate, and a new synthesis of fluoromethyl nitrate use the metathesis of the corresponding iodomethanes with silver nitrate. Both compounds were identified by spectroscopy and the structures determined for in situ grown crystals by X‐ray diffraction as well as in the gas phase by electron diffraction. Fluorination leads to structures with shorter C−O and N−O bonds, has an energetically destabilizing effect and increases friction sensitivity, but decreases detonation performance.
Green facile fabrication of polyimide by microwave‐assisted hydrothermal method and its decomposition dynamics
Authors: Zhuo Longhai , Tang Shulin , Zhao Kaiyan , Xie Fan , Bai Yang
Published: October 2019

A microwave‐assisted hydrothermal technique was proposed in this work to fabricate polyimide using ethanol as sole solvent, and the decomposition dynamics of the resulting polyimide was also investigated. The preparation process involved that the ammonium carboxylic ester intermediates could be able to cyclize de‐alchoholation, thus generating imide ring structures. The obtained polyimide exhibited excellent thermal properties. Specifically, the glass transition temperature of the polyimide was around 267.8 °C, and it begun to decompose gradually from about 550 °C. A novel method was employed to choose the dynamics model according to the linear correlation between g(α) and 1/β. As a result, the three‐dimensional diffusion (Jander) model was much more suitable for the thermal decomposition process of the resulting polyimide, and the thermal decomposition mechanism was explained by using the model. The apparent activation energy (E
a) values calculated by Flynn–Wall–Ozawa and Kissinger methods were similar showing the same variation tendency. Furthermore, a series of fitting polynomials for E
a and pre‐exponential factor (A) values were achieved to reflect the trend more accurately. The dynamics results revealed that the decomposition process was complex and could be regarded as multistep reactions. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48484.
Polybenzoxazine thermosets with enhanced toughness via blending with phthalazinone‐bearing thermal plastic copoly(aryl ether nitrile)s
Authors: Zong Lishuai , Li Jinlong , Liu Cheng , Zu Yuan , Li Nan , Wang Jinyan , Jian Xigao
Published: October 2019

Matrix resin with excellent toughness finds extensive applications in structural material fields recently. In this article, phthalazinone‐bearing copoly(biphenyl ether nitrile) (PPBEN) was synthesized, followed by solution blending with commercial benzoxazine resins to enhance their toughness. The relationship between loading amount of PPBEN and combined performance of the blend system was systematically detected via the characterization of their curing behavior, thermal properties, mechanical properties, and surface morphology. The results indicated that the presence of PPBEN significantly improved the impact strength of polybenzoxazine (PBOZ) when with 10% PPBEN loading, the impact strength of PPBEN/PBOZ blends was 202% higher than that of neat PBOZ. Simultaneously, the blending system maintained a commendable flexural strength, modulus, glass transition temperature, and thermal stability. The morphology study suggested that PPBEN microparticles dispersing uniformly in bulk played an important role in releasing external energy and were responsible for final toughness during impact process. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020,137, 48508.
Rubber fatigue life prediction using a random forest method and nonlinear cumulative fatigue damage model
Authors: Liu Qiaobin , Shi Wenku , Chen Zhiyong
Published: October 2019

In this study, a random forest machine‐learning method is introduced on the basis of the analysis of measured constant amplitude stress fatigue data. This method aims to predict rubber fatigue life under constant amplitude stress. Strain mean value, strain amplitude, and strain ratio are used as independent variables, and the prediction model of rubber fatigue life under constant amplitude stress is established. A nonlinear cumulative fatigue damage model is proposed to calculate rubber fatigue life under the variable amplitude stress. Results show that the random forest method has high precision and generalization capability for rubber fatigue life prediction under constant amplitude stress and the nonlinear cumulative fatigue damage model could be employed to calculate the fatigue life of rubber under variable amplitude stress with enough accuracy according to the constant amplitude stress fatigue life data. This research can provide a reference for rubber fatigue life prediction. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48519.
Swelling behavior of butyl and chloroprene rubber composites with poly(sodium acrylate) showing high water uptake
Authors: Oyama Yuya , Hiejima Yusuke , Nitta Koh‐hei
Published: October 2019

Water‐swellable rubber (WSR) comprises super absorbent polymer (SAP) embedded in a rubber matrix and has been commonly used as sealants and caulks, in which high water uptake and sufficient mechanical strength are required. In this work, we investigated the swelling behavior and mechanical properties of rubber composites comprising SAP powders. A reinforcement effect is caused by the SAP particles, which are described using a modified Guth–Gold equation up to the semi‐dilute region. The complex modulus shows upper deviation at high SAP content owing to network formation between SAP particles. The swelling force of the WSR is explained by the amount of SAP particles in the surface layer of the matrix up to the semi‐dilute region. The formation of the SAP network leads to an appreciable increase in the swelling force of WSR, as SAP particles embedded in the matrix also contribute to the swelling of WSR. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48535.
Electrochemical hydrogen peroxide nanosensor using a reduced graphene oxide‐poly(6‐(4H‐dithieno[3,2‐b:2′,3′‐d]pyrrol‐4‐yl)hexan‐1‐amine) hybrid‐modified electrode
Authors: Azak Hacer
Published: October 2019

The construction and biofunctionalization of graphene‐based conjugated polymer nanocomposite that included reduced graphene oxide‐poly DTP‐NH2 hybrid‐modified glassy carbon electrode (GCE) for the electrochemical H2O2 sensing were accomplished in this work. For the construction of the hydrogen peroxide bioassay, as an initial step of fabrication of the nanobiosensor, a novel conductive polymer structure was synthesized by the Suzuki‐Miyaura coupling reaction and structural characterization was carried out by 1H‐NMR and Mass spectroscopy techniques. Then, graphene oxide was chemically synthesized according to Hummers' method to expand the effective surface area to enhance the interaction between enzymes and conjugated polymers. This synthesized structure was assembled by an electrochemically polymerized conductive polymer with graphene oxide on a GCE. The modified glassy electrode surface was obtained by covalent bonding of the electrochemically polymerized DTP‐NH2 with graphene oxide and coated on each well as biomimetic material. The structure and sensing properties of the nanosensing hybrid structure were investigated using UV–vis, AFM, SEM, and XRD. Thanks to the fast electron transfer at the poly(DTP‐NH2)/rGO nanocomposite electrode interface, the developed biosensor exhibits a fast and linear amperometric response upon H2O2. Finally, a biosensor that is more selective and sensitive to H2O2 was developed. Also, the Poly(DTP‐NH2)/rGO nanocomposite based Hydrogen Peroxide Nano sensor displayed excellent selectivity as well as good reproducibility and stability. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48538.
Bosutinib Acts as a Tumor Inhibitor via Downregulating Src/NF‐κB/Survivin Expression in HeLa Cells
Authors: Yu Liang , Guo Weiqiang , Liu Ling , Zhang Guoping , Zhang Fahuang , Qu Yuan , Liu Yining , Li Hui , Li Huiwu
Published: October 2019

Efforts have been made to find effective medical drugs for cervical cancer treatment. The incidence of cervical cancer ranks second among women, and is a serious threat to women's health. Aberrant activation of the nonreceptor protein tyrosine kinases such as Src is commonly observed in progressive stages of human tumors. Thus, targeting Src kinase could be a promising strategy for cervical cancer therapy. In this study, we explored the potential utility of bosutinib in the treatment of cervical cancer. We found that bosutinib, as a potent dual Src/Abl inhibitor, could exert anti‐tumor effects on cervical cancer. Bosutinib inhibited cervical cancer cells proliferation and colony formation ability in a dose‐dependent manner, and also induced apoptosis. Mechanistically, bosutinib effectively decreased the activity of Src/NF‐κB/survivin signaling pathway. Our study provided a biological rationale to test bosutinib as a valuable therapeutic option for cervical cancer patients. Anat Rec, 302:2193–2200, 2019. © 2019 American Association for Anatomy
Fluorescent “Turn‐on” Sensing Based on Metal–Organic Frameworks (MOFs)
Authors: Karmakar Avishek , Samanta Partha , Dutta Subhajit , Ghosh Sujit K.
Published: October 2019

Metal–organic frameworks (MOFs) have evolved as an exciting class of materials in the domain of porous materials. The unique features of these materials arise from the combined properties of metal ions/clusters and organic struts which form the building blocks of these fascinating architectures. Among other multifarious applications, MOFs have shown tremendous applications as sensory materials for a wide variety of species. The signal transduction induced mechanism in these confined nanospaces generate optical output in response to a particular analyte which can be detected by wide variety of detection techniques. Fluorometric methods of sensing is one of widely studied method over past few decades. MOF‐based fluorometric detection is a key research theme developed over the past few years. In this review, we give a brief overview of the recent developments of MOFs as “turn‐on” sensors for a wide range of analytes (viz. cations, anions, volatile organic compounds (VOCs), etc.).
Effects of Physical Damage in the Intermediate Phase on the Progression of Amyloid β Fibrillization
Authors: Tashiro Ryu , Taguchi Hiroaki , Hidaka Kumi , Endo Masayuki , Sugiyama Hiroshi
Published: October 2019

Understanding the mechanism responsible for the progression of amyloid deposition is important for developing methods to suppress this process in the treatment of Alzheimer's disease. The effects of physical damage during the transition phase of amyloid β fibril formation are unclear. In this study, we used high‐speed atomic force microscopy to investigate the effects of damage to the intermediates of amyloid β in real time. Physical damage to intermediates did not suppress, but instead promoted fibrillization. This progression was accompanied by morphological changes from globular oligomers to protofibrils. These results suggest that the properties of the intermediates, such as structural fragility and stability, are highly related to the rate of fibrillization.
Electroluminochromic Materials and Devices Based on Metal Complexes
Authors: Zhuang Yanling , Guo Song , Deng Yongjing , Liu Shujuan , Zhao Qiang
Published: October 2019

Electroluminochromism (ELC) refers to an interesting phenomenon exhibited by a material whose luminescent properties can be reversibly modulated under an electrical stimulus. Such a luminescence‐switching property has been widely used in various organic optoelectronic devices because it can simultaneously detect electrical and optical signals. Metal complexes are the promising candidates for ELC materials due to their sensitivity to an electrical stimulus. Herein, recent progress on electroluminochromic materials and devices based on various metal complexes has been summarized. Meanwhile, the applications of these complexes in data recording and security protection have also been discussed. Finally, a brief conclusion and outlook are presented, pointing out that the development of electroluminochromic metal complexes with excellent performance is important because they play a vital role in future intelligent optoelectronic devices.
Recent Advances in the Deoxydehydration of Vicinal Diols and Polyols
Authors: Donnelly Liam J. , Thomas Stephen P. , Love Jason B.
Published: October 2019

Deoxydehydration (DODH) is one of the most promising tools to reduce the oxygen content of biomass (sugars and polyols) and provide analogues of platform chemicals that are derived from fossil resources. This reaction converts a vicinal diol into an alkene and is typically catalyzed by high‐oxidation‐state metal‐oxo compounds in the presence of a stoichiometric reductant, with examples of both homogeneous and heterogeneous systems. This minireview will highlight the developments in this field over the past 5 years and focus on efforts to solve the problems that currently prevent DODH being performed on a commercial scale, including the nature of the reductant, substrate scope and selectivity, and catalyst recovery and expense.
Chromospheric activity behavior of an eclipsing binary system KOI 68AB
Authors: Kaya N. Ö. , Dal H. A.
Published: October 2019

We present the results obtained from KOI 68AB's light variation, which exhibits a sinusoidal light variation due to the stellar spots. Two active regions longitudinally separated by about 180° between the latitudes of +70° and +110° were found. A total of 313 flares were determined, and flare parameters were calculated. The One Phase Exponential Association model was derived using these parameters. The energy saturation parameter Plateau value was found to be 1.219 ± 0.088 s, and its time scale parameter half‐life value was found to be 1,190 s. The flare number per hour, known as N1 frequency, was found to be 0.02406 h−1, while the flare‐equivalent duration emitted per hour, known as N2, was found to be 0.000008. Considering new spectral observations, the target seems to be an eclipsing binary system. Because of this, the light curve is analyzed under an assumption that the target is an eclipsing binary. In these analyses, the sum of the fractional radii is found to be 0.1908, and the fractional radii ratio is 1.8973.