bluuebunny/crossref_metadata_2025 huggingface dataset:
Frictional Resistance of Non Coated and Epoxy Coated Superelastic NiTi Wires used for Aligning in Three Types of Brackets
Authors: Ravishankar Monisha , Duraisamy Sangeetha , Rajaram Krishnaraj , Kannan Ravi , Sivakumar Nishanth
Published: May 2022

Introduction: Coated archwires are preferred in combination with aesthetic orthodontic brackets by orthodontists over non metallic aesthetic archwires. Studies evaluating the frictional properties of epoxy coated round superelastic Nickel Titanium (NiTi) archwires are limited to stainless steel brackets. Aim: To evaluate and compare the frictional resistance of an epoxy coated 0.016" superelastic NiTi archwire in stainless steel, composite and ceramic brackets and to compare it with the frictional resistance generated by non coated 0.016" superelastic NiTi archwire in same brackets. Materials and Methods: An in-vitro experimental study was conducted in the Department of Orthodontics at SRM Dental College from January to February 2020. Frictional resistance of 30 epoxy coated aesthetic 0.016" upper superelastic NiTi wires (G4™ Nickel Titanium, 0.016, Upper Trueform™ I, ToothColored) and 30 conventional 0.016" upper superelastic NiTi wires (G4™ Nickel Titanium, 0.016, Upper Trueform™) from G&H® orthodontics while sliding across three different types of brackets were evaluated. Twenty stainless-steel (Gemini® 3M unitek, Monrovia, California), 20 composite (FLI® RMO, Denver, Colo.), and 20 gemini clear ceramic (Gemini clear ® 3M unitek, Monrovia, California) 0.022x0.028" Slot Roth prescription maxillary first premolar brackets were used. The brackets and archwires were divided into six groups of different bracket and archwire combination with 10 samples in each. An Instron testing machine with a 10 N tension was used to measure the frictional resistance. The obtained values were analysed using One-way ANOVA and followed by Post Hoc Tukey HSD for multiple comparison. Results: Coated wires generated significantly high friction in ceramic brackets (136.90±3.79 gms) followed by composite brackets (125.66±3.44 gms) and stainless steel brackets (92.53±8.70 gms). Non non coated wires generated significantly high friction with ceramic brackets (89.60±2.90 gms) whereas the friction generated in composite (70.87±5.79 gms) and stainless steel brackets (67.70±2.80 gms) was not significantly different. Conclusion: Epoxy coating increased the frictional resistance generated by the 0.016 superelastic NiTi archwires irrespective of bracket materials. The coated wires generated less friction in composite brackets compared to ceramic brackets. Further clinical trial are recommended to evaluate the aligning efficacy of these archwires in aesthetic brackets.
Effects of Vitamin E on Chronic Haematoxicity of Paraquat Exposed Male Albino Rats (Rattus norvegicus)
Authors: Nnamdi Okolonkwo Benjamin , Nyebuchi Jonathan , Collins Adjekuko Ohwonigho , Udu Zebedee Loveday
Published: May 2022

Paraquat is an environmental pollutant that is associated with some disorders including alteration of some harmatological indices and is a concern to public health. Vitamin E has antioxidant property and other characteristic roles that ameliorate toxic effect. 200 male albino rats weighing 0.2±0.02kg on the average were divided into four main groups (A, B, C, and D) with 50 rats in one group. The “A” group was not served paraquat solution and was used as the control group. Group “B”, “C”, “D” being the treatment group were given dose rates of paraquat of 0.02g, 0.04g, and 0.06g, of paraquat per kg rat respectively every two weeks for three months. The main groups further had subgroups. “A”, “A0” and “AVE”; “B”, “B0” and “BVE”; “C” had “C0” and “CVE”; and “D”, “D0” and “DVE” subgroups. Vitamin E was not given to subgroups “A0”, “B0”, “C0” and “D0” subgroups while “AVE”, “BVE”, “CVE” and “DVE” were fed orally with 500mg of vitamin E therapy every week. Treatment with vitamin E began three months after paraquat treatment. At the end of the weekly treatment with vitamin E for a month, the rats were sacrificed and their blood samples were obtained and analyzed for PCV, Hb, WBC, neutrophil and lymphocyte. A0, B0, C0 and D0 intergroup comparison was statistically significant, p-value<0.05 in PCV and Hb levels while their WBC, neutrophil and lymphocyte had no statistical significance. Ave, Be, Cve and Dve intergroup comparison was statistically significant, p-value<0.05 in PCV and Hb levels while WBC, lymphocyte and neutrophils had no statistical significance among the groups. Intra group comparison showed that only PCV and Hb were significant between groups, p-value<0.05. This study confirms that vitamin E is potent in treating paraquat toxicity in male albino rats on one month of weekly treatment.
Synergistic Effect of Vitamin E and C Treatment on Paraquat Induced Haemotoxicity in Rattus norvegicus
Authors: Nnamdi Okolonkwo, Benjamin , Nyebuchi Jonathan, , Collins Adjekuko, Ohwonigho , Udu Zebedee, Loveday
Published: May 2022

Paraquat is a herbicide, commonly used in the agricultural practices to prevent weed infestation. The Environmental Protection Agency in some countries has placed a restriction on paraquat and there is no identified record of chelating agent or antidote for paraquat. Oxidation of paraquat results in the of superoxides formation. Superoxides generation causes cellular damage. Vitamin C (ascorbic acid) is a water soluble vitamin, with antioxidant potential. It is efficient in clearing free radicals, including hydroxyl radicals, peroxyl radicals and superoxide anion. E is a fat soluble vitamin but considered to be relatively safe when compared to other fat-soluble vitamins Empirical evidence has shown therapeutic efficacy of vitamin E hence its common use in therapeutics. Our goal is to determine the potency of combined effect of vit. E + C on paraquat induced toxicity in male albino rats. As much as 200 rats were obtained and parted into four main groups of 50 rats each. The groups were A, B C and D. The “A” group was not induced with paraquat; groups “B”, “C”, and “D” was induced every two weeks with 0.02g, 0.04g, and 0.06g of paraquat per kg of rat respectively for three months. Each of the main groups had subgroups. “A” group had “A0” and “AVEC” subgroups; “B” group had “B0” and “BVEC” subgroups; “C” group had “C0” and “CVEC” subgroups; “D” group had “D0” and “DVEC” subgroups. “A0”, “B0”, “C0” and “D0” subgroups were treated with paraquat only, while “AVEC”, “BVEC”, “CVEC” and “DVEC” were treated orally with 500mg of vitamin E and 2000mg/l of vitamin C medicated water every week. Comparison of intergroups A0, B0, C0 and D0 was statistically significant, p-value<0.05 in Hb and PCV. There was no statistical difference with respect to T-WBC, neutrophil, and lymphocytes across the groups. AVEC, BVEC, CVEC and DVEC intergroup comparison was statistically significant, p-value<0.05 in Hb and PCV, whereas in comparison with T-WBC, neutrophil, and lymphocytes were not statistically significant among the groups. The finding from this study has shown that a combination of vitamin E and C therapy is potent against paraquat toxicity in male albino rats on one month of weekly treatment and can be used to treat the condition on a weekly basis.
Haematological Recovery by Vitamin E and C on Paraquat Inflicted Haematological Insult in Rattus norvegicus
Authors: Nnamdi Okolonkwo, Benjamin , Nyebuchi Jonathan, , Collins Adjekuko, Ohwonigho , Jumbo Mieiwari, Ibifubara
Published: May 2022

Background: Vitamin E (alpha tocopherol) is a fat-soluble vitamin which plays an important role in sustaining healthy metabolism and physiological functions in the body. Earlier studies showed that vitamin E could ameliorate the damaging effect caused by oxidative stress induced by free radicals. Vitamin C (Ascorbic acid) is a water soluble vitamin which is needed for the formation of collagen and intracellular materials. Hence, it is essential in wound healing and recovery tissue recovery.

Aim: This study was done to evaluate the haematological effect of Vitamin E and C combination therapy on the chronic toxicity of paraquat in Wister rats.

Methodology: A total of 200 male Wister rats were used for the study. The rats were divided into four main groups of 50 rats in each group (A, B, C, D) and was further subgrouped, having 25rats per subgroup. “A” group was not induced with paraquat while “B”, ‘C” and “D” groups were induced in increasing dose of 0.02g, 0.04g and 0.06g respectively. “A” group had two subgroups; “Ao” and “Avec” which represented the sub-group not treated with Vit E and C and the subgroup treated with 500mg vitamin E and 2000mg/l of vitamin C medicated water respectively. This also applied to group “B”, “C” and “D”. paraquat was induced every forth night for three month followed by weekly treatment for one month.

Results: The result obtained showed a significant decrease in PCV, Hb, and TWBC count among Ao, Bo, Co and Do groups at p<0.05 but no significant difference in the neutrophil and lymphocyte count. Also, there was a significant difference among Ave, Bvec, Cvec and Dvec groups. On intra-group comparison, there was a significant increase in the Hb, and PCV of subgroups Avec, Bvec, Cvec and Dvec at p<0.05 but no significant difference in the TWBC count and differentials.

Conclusion: This indicates that Vitamin E and C combination supplementation had an ameliorative effect on the PCV and Hb value but no effect on the TWBC count and differentials on paraquat toxicity.
Income Generation through Value Addition of Flower Crops: A Review
Authors: Shah Ali Haidar , Singh Arvinder , Laishram Nomita , Gill Komaljeet
Published: May 2022

Value added floriculture is a process of increasing the economic value and consumer appeal of any floral commodity through processing and packaging diversification. The value addition for marketing flowers includes adoption of postharvest technology and improved logistics. Value- addition ensures high premium to the grower, while providing more acceptable quality products for the domestic and export market, and it provides the most important aspects of marketing and give the customers a reason to buy such products. Value addition reduces post-harvest losses and diversifies the economic base of rural communities. The value-added products can be classified into three categories namely fresh flower products, dried flower products and processed flower products. The success of floral industry lies upon by strengthening the fresh flower market through value addition. Dry flower value added products of flowers through different methods have shown promising results. Tinting of cut carnation with food dye Pink and Orange Red @ 5% recorded the fastest uptake of 1 hour Jasminum sambac flowers harvested at the fully open stage yielded better quality essential oil compared with flowers harvested at the closed bud stage. Marigold is one of the richest source of carotenoids especially lutein which possess antioxidant activities and moreover intake of lutein helps in curing age related macular diseases. Natural dyes are mostly used in the colouring of textiles, drugs, cosmetics, etc. Chrysanthemum petals can be used as a substitute of synthetic reactive dyes for dyeing of cotton and silk fabrics (Das et al., 2016). Marigold flower provides a source of carotenoids commercially used in food colouring industries and poultry feed high in carotenoids has been shown to increase performance and egg yolk color as well as decrease egg cholesterol levels.
Empirical Modeling and Optimization of Base Activated Ngbo Catalysts in Esterification Reaction Using Response Surface Methodology
Authors: Nwobasi V. N. , Igbokwe Philomena K. , Okewale Akindele Oyetunde
Published: May 2022

In this work, Box-Behnken’s Response Surface Methodology (RSM) was applied to study the esterification reaction effectiveness of base-activated Ngbo clay catalyst. The esterification was monitored based on temperature, time duration, amount of reactant, catalyst weight, and particle size. The Box-Behnken’s Response Surface Methodology indicates that the base  clay-catalyzed esterification reactions proceed through dual Acid-complex and Alcohol- complex mechanisms, with the alcohol mechanism dominating. The acetic acid and ethanol esterification efficiencies by base-activated Ngbo clay catalyst optimized using RSM models indicated the esterification percentage was ˃99%. The predicted and experimental values  under the same conditions showed less than 5% difference, thereby making the Box-Behnken design approach an efficient, effective, and reliable method for the esterification of acetic  acid with ethanol. The produced catalyst was optimized using A-One way ANOVA modelled,   which indicated that the correlation coefficient of the regression was 0.9940. The result implied  that 99.40% of the total variation in the esterification reaction was due to the experimental variables. The obtained data in this study indicated that this process could be applied in the esterification of acetic acid to avoid the drawbacks of corrosion, loss of catalyst, and environmental problems.
G‐CSF/GM‐CSF‐induced hematopoietic dysregulation in the progression of solid tumors
Authors: He Kai , Liu Xi , Hoffman Robert D. , Shi Rong‐Zhen , Lv Gui‐Yuan , Gao Jian‐Li
Published: May 2022

There are two types of abnormal hematopoiesis in solid tumor occurrence and treatment: pathological hematopoiesis, and myelosuppression induced by radiotherapy and chemotherapy. In this review we primarily focus on the abnormal pathological hematopoietic differentiation in cancer induced by tumor‐released granulocyte colony‐stimulating factor (G‐CSF) and granulocyte‐macrophage colony‐stimulating factor (GM‐CSF). As key factors in hematopoietic development, G‐CSF/GM‐CSF are well‐known facilitators of myelopoiesis and mobilization of hematopoietic stem cells (HSCs). In addition, these two cytokines can also promote or inhibit tumors, dependent on tumor type. In multiple cancer types, hematopoiesis is greatly enhanced and abnormal lineage differentiation is induced by these two cytokines. Here, dysregulated hematopoiesis induced by G‐CSF/GM‐CSF in solid tumors and its mechanism are summarized, and the prognostic value of G‐CSF/GM‐CSF‐associated dysregulated hematopoiesis for tumor metastasis is also briefly highlighted.
Viscoelastic Damping and Wave Cutoff of Titanium Alloy and Lattices
Authors: Goyal Karan , Rueger Zach , Davis Evan , Lakes Roderic S.
Published: May 2022

The 3D‐printed titanium alloy Ti5553 solid and octet truss lattice specimens are studied via resonant ultrasound spectroscopy, free decay of vibration and quasi‐static methods to determine viscoelastic damping. Damping in solid alloy and a lattice is between 10−4 and10−3. Much of the damping at high sonic frequency is attributed to stress‐induced heat flow between heterogeneities due to 3D printing. Pulsed wave ultrasound experiments disclose reverberation in the cell structure of the lattice. Continuous wave ultrasound experiments show that the transmissibility in the lattice rolls off beginning at about 50 kHz and becomes negligible above 110 kHz. By contrast, the polymer polymethyl methacrylate (PMMA), though it is viscoelastic, readily transmits waves up to 1 MHz. The cutoff frequency in the lattice is associated with the structure size, not intrinsic damping in the alloy. The octet truss lattice, in addition to providing good mechanical performance, is also an ultrasonic metamaterial.
Controlled Growth of the Interface of CdWOx/GDY for Hydrogen Energy Conversion
Authors: Luan Xiaoyu , Zheng Zhiqiang , Zhao Shuya , Xue Yurui , Li Yuliang
Published: May 2022

Directly extracting hydrogen energy from water in one device to achieve sustainable hydrogen energy generation‐conversion‐electricity storage system is an ideal major step forward for enabling a zero‐pollution, hydrogen‐fueled economy. The new concept of hydrogen energy conversion can be enabled by spontaneous reduction of nitrate to ammonia driven by potential differences between the well‐matched anode and cathode, leading to the full use of the electrochemical redox reactions to generate electric energy. The hydrogen energy in the acidic electrolyte can be transformed to electric energy with the rationally assembled primary battery, which can simultaneously power the electric devices and produce high value‐added ammonia. The new concept of hydrogen conversion device shows a record‐high specific capacity of 15 500 mA h g–1 and achieves the highest ammonia production rate (149 mmol gcat–1 h–1) and Faradaic Efficiency (99.2%) in acidic electrolytes. This work opens a new direction for hydrogen conversion and utilization which has obvious advantages over lithium and battery solutions.
Flexible Transparent High‐Efficiency Photoelectric Perovskite Resistive Switching Memory
Authors: Liu Xiaomin , Ren Shuxia , Li Zhenhua , Guo Jiajun , Yi Shenghui , Yang Zheng , Hao Weizhong , Li Rui , Zhao Jinjin
Published: May 2022

Perovskite resistive random‐access memory (RRAM) is a promising candidate for next‐generation logic, adaptive and nonvolatile memory devices, because of its high ON/OFF ratio, low‐cost fabrication, and good photoelectric regulation performance. In this work, a flexible transparent CsPbBr3 quantum dots (QDs) mixed in graphene oxide (GO) RRAM device is introduced, which is controllable by both an electric field and illumination. Under illumination, the ON/OFF ratio of the Ag/CsPbBr3 QDs:GO/ITO device is ≈1.4 × 107, which is 1077 times larger than that in the dark condition (1.3 × 104). The SET/RESET voltages are +2.28/−2.04 V and +1.68/−1.08 V under the dark and illumination conditions, respectively. As a flexible memory device, the resistances are little affected by the bending curvatures and load‐cycling. Before and after 104 bending cycles with a radius of 5 mm under illumination, the ON/OFF ratios keep in the same order, which are 2.5 × 107 and 2.3 × 107, respectively. The ratio values are 8.8 × 104 and 2.9 × 104 under the dark condition, respectively. This innovative resistive memory based on the CsPbBr3 QDs:GO hybrid film supports a huge space for the development of photoelectrical dual‐controlled flexible RRAM devices.
Stability of Platinum‐Group‐Metal‐Based Electrocatalysts in Proton Exchange Membrane Fuel Cells
Authors: Zhu Enbo , Wu Menghao , Xu Haozhe , Peng Bosi , Liu Zeyan , Huang Yu , Li Yujing
Published: May 2022

Proton exchange membrane fuel cells (PEMFCs) have attracted significant interest as a promising alternative technology to the combustion engine to power next‐generation vehicles with zero emission. Among the various technological targets, system cost and durability are currently identified as the main obstacles toward large‐scale implementation of PEMFCs. Platinum‐group‐metal‐based (PGM‐based) catalysts are the most efficient catalyst for the rate‐limiting cathodic oxygen reduction reaction in PEMFCs and take the highest share in the cost breakdown. Therefore, the stability of PGM‐based electrocatalysts plays a significant role in the development of PEMFCs. This review will summarize the recent progress made on the understanding of both the fundamental chemical and structural stability of PGM‐based catalysts, and their durability in operational PEMFC devices. It calls for systematic studies on the chemical, structural, and operational durability of the PGM‐based catalyst and the need to coin practical descriptors for catalyst design with both superior activity and durability for cost‐effective and high‐performance PEMFCs.
Rational Design of High‐Performance Keratin‐Based Hemostatic Agents
Authors: Wang Yumei , Xu Yingqian , Zhang Zhi , He Ye , Hou Zongkun , Zhao Zhibin , Deng Jia , Qing Rui , Wang Bochu , Hao Shilei
Published: May 2022

Keratins are considered ideal candidates as hemostatic agents, but the development lags far behind their potentials due to the poorly understood hemostatic mechanism and structure–function relations, owing to the composition complexity in protein extracts. Here, it is shown that by using a recombinant synthesis approach, individual types of keratins can be expressed and used for mechanism investigation and further high‐performance keratin hemostatic agent design. In the comparative evaluation of full‐length, rod‐domain, and helical segment keratins, the α‐helical contents in the sequences are identified to be directly proportional to keratins’ hemostatic activities, and Tyr, Phe, and Gln residues at the N‐termini of α‐helices in keratins are crucial in fibrinopeptide release and fibrin polymerization. A feasible route to significantly enhance the hemostatic efficiency of helical keratins by mutating Cys to Ser in the sequences for enhanced water wettability through soluble expression is then further presented. These results provide a rational strategy to design high‐efficiency keratin hemostatic agents with superior performance over clinically used gelatin sponge in multiple animal models.
Mn2+/Fe3+/Co2+ and Tetrasulfide Bond Co‐Incorporated Dendritic Mesoporous Organosilica as Multifunctional Nanocarriers: One‐Step Synthesis and Applications for Cancer Therapy
Authors: Liu Bin , Feng Lili , Bian Yulong , Yuan Meng , Zhu Yanlin , Yang Piaoping , Cheng Ziyong , Lin Jun
Published: May 2022

Enriching the application of multifunctional dendritic mesoporous organosilica (DMOS) is still challenging in anti‐cancer research. Herein, manganese ions, iron ions, or cobalt ions and tetrasulfide bonds are co‐incorporated into the framework of DMOS to yield multifunctional nanoparticles denoted as Mn‐DMOS, Fe‐DMOS, or Co‐DMOS by directly doping metal ions during the synthetic process. Due to co‐incorporation of metal ions and tetrasulfide bonds, these designed nanocarriers have more functions rather than only for cargo delivery. As proof of concept, the nanocomposite is established based on Mn‐DMOS as an efficient nanocarrier for indocyanine green (ICG) delivery and modification with polyethylene glycol. In the tumor microenvironment, the generated hydrogen sulfide (H2S) arising from the reaction between tetrasulfide bond and over‐expressed glutathione (GSH) causes mitochondrial injury to reduce cellular respiration. The released Mn2+ from the rapidly decomposed nanocomposite catalyzes the endogenous hydrogen peroxide to produce oxygen (O2). The photothermal effect from the released ICG initiated by the near‐infrared light induces cancer cells apoptosis and simultaneously enhances the content of blood O2 at tumor sites. Therefore, due to the GSH depletion and trimodal O2 compensation, the photodynamic therapy efficiency of ICG has significantly improved. In brief, these designed nanocarriers will play advanced roles in cancer therapy.
Interface‐Modulated Resistive Switching in Mo‐Irradiated ReS2 for Neuromorphic Computing
Authors: Pam Mei Er , Li Sifan , Su Tong , Chien Yu‐Chieh , Li Yesheng , Ang Yee Sin , Ang Kah‐Wee
Published: May 2022

Coupling charge impurity scattering effects and charge‐carrier modulation by doping can offer intriguing opportunities for atomic‐level control of resistive switching (RS). Nonetheless, such effects have remained unexplored for memristive applications based on 2D materials. Here a facile approach is reported to transform an RS‐inactive rhenium disulfide (ReS2) into an effective switching material through interfacial modulation induced by molybdenum‐irradiation (Mo‐i) doping. Using ReS2 as a model system, this study unveils a unique RS mechanism based on the formation/dissolution of metallic β‐ReO2 filament across the defective ReS2 interface during the set/reset process. Through simple interfacial modulation, ReS2 of various thicknesses are switchable by modulating the Mo‐irradiation period. Besides, the Mo‐irradiated ReS2 (Mo‐ReS2) memristor further exhibits a bipolar non‐volatile switching ratio of nearly two orders of magnitude, programmable multilevel resistance states, and long‐term synaptic plasticity. Additionally, the fabricated device can achieve a high MNIST learning accuracy of 91% under a non‐identical pulse train. The study's findings demonstrate the potential for modulating RS in RS‐inactive 2D materials via the unique doping‐induced charged impurity scattering property.
ALTEN: A High‐Fidelity Primary Tissue‐Engineering Platform to Assess Cellular Responses Ex Vivo
Authors: Law Andrew M. K. , Chen Jiamin , Colino‐Sanguino Yolanda , Fuente Laura Rodriguez de la , Fang Guocheng , Grimes Susan M. , Lu Hongxu , Huang Robert J. , Boyle Sarah T. , Venhuizen Jeron , Castillo Lesley , Tavakoli Javad , Skhinas Joanna N. , Millar Ewan K. A. , Beretov Julia , Rossello Fernando J. , Tipper Joanne L. , Ormandy Christopher J. , Samuel Michael S. , Cox Thomas R. , Martelotto Luciano , Jin Dayong , Valdes‐Mora Fatima , Ji Hanlee P. , Gallego‐Ortega David
Published: May 2022

To fully investigate cellular responses to stimuli and perturbations within tissues, it is essential to replicate the complex molecular interactions within the local microenvironment of cellular niches. Here, the authors introduce Alginate‐based tissue engineering (ALTEN), a biomimetic tissue platform that allows ex vivo analysis of explanted tissue biopsies. This method preserves the original characteristics of the source tissue's cellular milieu, allowing multiple and diverse cell types to be maintained over an extended period of time. As a result, ALTEN enables rapid and faithful characterization of perturbations across specific cell types within a tissue. Importantly, using single‐cell genomics, this approach provides integrated cellular responses at the resolution of individual cells. ALTEN is a powerful tool for the analysis of cellular responses upon exposure to cytotoxic agents and immunomodulators. Additionally, ALTEN's scalability using automated microfluidic devices for tissue encapsulation and subsequent transport, to enable centralized high‐throughput analysis of samples gathered by large‐scale multicenter studies, is shown.
Tunable Linearity of Weight Update in Low Voltage Synaptic Transistors with Periodic High‐k Laminates
Authors: Li Yushan , Tao Ruiqiang , Zhang Beijing , Shuai Wentao , Zhou Yue , Chang Cheng , Huang Ting , Xu Zihao , Fan Zhen , Zhou Guofu , Lu Xubing , Liu Junming
Published: May 2022

Synaptic transistors have shown great potential in neuromorphic computing, but remain challenging to simulate linear weight updates through conductance switching under low voltage spiking operation. Here, a low voltage and near‐linear weight update synaptic transistor are proposed by developing an interfacial‐defect dominated floating gate structure, in which inter‐diffused defects are surrounded by near‐defect free and ultrathin (1 nm) dielectrics in HfO2/Al2O3 periodic high‐k laminates. In the laminates, inter‐diffused defects are surrounded by near‐defect free and ultrathin (1 nm) HfO2 and Al2O3 tunneling layers deposited by atom layer deposition, which contributes to the accurate regulation of multi‐level charge trapping confined at independent interfacial regions, and trades off the low operation voltages and the nonvolatile characteristics of the devices. A very small conductance switching nonlinearity (NL = 0.05) and an excellent image recognition accuracy (93.1%) are demonstrated under low voltages (−3 V/1.8 V) in an optimized device with (1 nm HfO2/1 nm Al2O3)3 laminates. Besides, the basic synaptic functions are successfully mimicked based on the long‐term plasticity. These results have referential significance for the future artificial synapse with low energy consumption and high efficiency.
XPEEM and MFM Imaging of Ferroic Materials
Authors: Ghidini Massimo , Maccherozzi Francesco , Dhesi Sarnjeet S. , Mathur Neil D.
Published: May 2022

The authors describe and compare two complementary techniques that are habitually used to image ferromagnetic and ferroelectric materials with sub‐micron spatial resolutions (typically 50 nm, at best 10 nm). The first technique is variable‐temperature photoemission electron microscopy with magnetic/antiferromagnetic/polar contrast from circularly/linearly polarized incident X‐rays (XPEEM). The second technique is magnetic force microscopy (MFM). Focusing mainly on the authors’ own work, but not exclusively, published/unpublished XPEEM and MFM images of ferroic domains and complex magnetic textures (involving vortices and phase separation) are presented. Highlights include the use of two XPEEM images to create 2D vector maps of in‐plane (IP) magnetization, and the use of imaging to detect electrically driven local reversals of magnetization. The brief and simple descriptions of XPEEM and MFM should be useful for beginners seeking to employ these techniques in order to understand and harness ferroic materials.
Fright but not fight‐or‐flight: Violent video games elevated stress markers, but did not impact muscle function, memory recall or food intake, in a randomized trial in healthy young men
Authors: Wells Jonathan C. K. , Michael Panos , Fewtrell Mary S. , Siervo Mario , Cortina‐Borja Mario
Published: May 2022

Objectives

Regular video game playing has been linked with obesity, but the underlying mechanisms remain unclear. Drawing on evolutionary life history theory, we hypothesized that playing violent video games, through activating the stress response, might increase the immediate demand for fuel by muscle and brain tissue, resulting in elevated appetite and food consumption.

Methods

We randomized 71 young adult men to play video games, involving either violent content or nonviolent puzzle‐solving, for 1 h. Over this period, we measured stress markers (blood pressure [BP], heart rate, visual‐analogue scale [VAS] self‐ratings), muscle function (handgrip strength) and cognitive function (memory recall test). Appetite was assessed by VAS, and by food intake using a test‐meal after the intervention. Linear mixed‐effects models were fitted to assess group effects and group:time effects.

Results

During the intervention, the violent video game group showed elevated systolic BP (∆ = 4.7 mm Hg, 95% CI 1.0, 8.4) and reported feeling more alert but less calm or happy. They showed no difference in grip strength or memory recall. They reported lower feelings of “fullness” but consumed similar food‐energy during the test‐meal.

Conclusions

Although playing a video game with violent content elevated physiological and perceived stress markers compared with a nonviolent game, this was not associated with markers of altered fuel distribution toward two tissues (muscle and brain) that contribute to the “fight‐or‐flight” response. Rather than more energy being allocated to the brain overall, energy may have been reallocated within the brain. This may explain why there was no compensatory increase in energy intake in the violent video game group.
A disposable ultrasensitive surface enhanced Raman spectroscopy biosensor platform fabricated from biodegradable zein nanofibers
Authors: Turasan Hazal , Cakmak Mukerrem , Kokini Jozef
Published: May 2022

In this paper, a natural polymer, zein, is converted into a disposable and environmentally friendly surface enhanced Raman spectroscopy (SERS) biosensor platform to detect toxins. First, protein nanofiber mats were fabricated using electrospinning. Next, the surface of the fibers was decorated with metallic nanoparticles to create hotspots for the detection of the target molecule. Four types of metallic nanoparticles were tested for sensitivity optimization: gold, silver, silver‐shelled‐gold, and a mixture of gold and silver nanoparticles. Silver‐shelled‐gold nanoparticles gave the highest SERS intensity, and at the concentration of 1012particles/ml, the highest enhancement factor (EF) of 2.49 × 106was reached, which is the highest EF ever reported for a zein‐based biodegradable platform. Acrylamide was used as the model food carcinogenic toxin and its detection with this nanofiber‐based platform gave a limit of detection of 2.06 ng/ml. This LOD is 104times lower than the limit of detection that was achieved previously with a zein‐based SERS platform. Other sensitive analytical methods (GC–MS and LC–MS/MS) gave LODs of 5–10 and 20–50 ng/ml for acrylamide, much higher than the method used in this study. This sensitivity is much lower than any other previous attempts to detect acrylamide with biodegradable sensors.
Incorporation ofCO2‐polyols into ester‐based waterborne polyurethane: An effective strategy to improve overall performance
Authors: Zhang Hongming , Han Guangping , Cheng Wanli , Liu Shunjie , Wang Xianhong
Published: May 2022

Amorphous structural CO2‐polyol was used to modify ester‐based water‐borne polyurethanes (WPUs), resulting in improved low temperature film forming and comprehensive hydrolysis/oxidation resistance properties. Excellent intact films can be easily formed even at 3°C by adding 5% CO2‐polyol into the ester‐based WPUs (namely PU5CO2). Moreover, WPUs modified by CO2‐polyol show superior hydrolysis/oxidation resistance properties than that of control samples based on castor oil or poly(propylene oxide) glycol. PU5CO2showed significantly enhanced retention tensile strength from 40% to 68.2% than that of pure ester‐based WPU after 5 h immersion in 1.5% NaOH solution, indicating an improved hydrolysis resistance. In addition, the PU5CO2displayed boosted oxidation resistance property with retention strength increased from 39% to 65%. Notably, the all‐around aging resistance of ester‐based WPUs intensified with an increase of CO2‐polyol content. This work indicates that the CO2‐polyol may be a promising modified material to improve comprehensive hydrolysis/oxidation resistance and low temperature film forming for ester‐based WPUs.
Shape memory, thermal conductivity, and mechanical property of polylactic acid and natural rubber composites reinforced by an inorganic thermal conductive network
Authors: Shi Hui‐Hong , Ruan Hui‐Xian , Chen Zong‐Ju , Zhang Yi , Zou Cheng‐Long , Zhang Xiu‐Cheng , Liu Bing , Xu Miao‐Jun , Li Bin
Published: May 2022

With the development and application of thermotropic shape memory polymer materials in the biomedical field, it is very crucial for these materials to improve their thermal conductivity efficiency and shape memory recovery rate by endowing them a high thermal conductivity. In our work, a PLA/NR/T‐ZnOw/GR shape memory composite was prepared by melt blending with tetrapod zinc oxide whisker (T‐ZnOw) and graphene (GR) as the double inorganic fillers and polylactic acid (PLA) and natural rubber (NR) as the polymer matrix. The synergism of T‐ZnOw and GR constructs a three‐dimensional (3D) thermal conductive network, making the thermal conductivity of PLA/NR/5wt%T‐ZnOw/2.5wt%GR increase to 1.215 W∙(m∙K)−1. The addition of T‐ZnOw reduces the agglomeration of GR in the PLA/NR matrix and the interfacial thermal resistance between the fillers and the matrix. It also improves the heat transfer rate, resulting in an excellent shape memory of PLA/NR/T‐ZnOw/GR with a morphology recovery rate of ca. 96%, a fixed rate of 95% and high thermal stability. The presented biodegradable shape memory composite with the 3D thermal conductive network is promising in the fields of medical treatment and intelligent sensors.
Effect of graphitic additives on the rheology of cellulose solutions for the preparation of templated carbon fiber precursors
Authors: Lundahl Meri J. , Sawada Daisuke , Merilä Markus , Hummel Michael
Published: May 2022

The performance of biobased carbon fiber (CF) can potentially be improved to a new level by enhancing its graphitization by including graphitic additives as structural templates in the precursor. Mixing these additives in the precursor spinning solution can influence the solution rheology and thus its spinning process and ensuing carbonization, though these effects are not well understood. Herein, we analyze the influence of carbon nanotube (CNT) and graphene oxide (GO) additives on the rheology of cellulose solutions in ionic liquid as well as the subsequent precursor and CF preparation. Addition of GO both thickened the solution and clearly increased its elastic (solid‐like) nature in comparison to pure cellulose solution in ionic liquid, while CNT only made the solution moderately more elastic. Still, solutions with both additives were spinnable into continuous precursor fibers, though the inclusion of GO somewhat disturbed cellulose alignment in the fiber, as observed through X‐ray diffraction. In addition, GO induced structural order development, observed as a decrease in the intensity and ratio between the Raman peaks at ~1300 cm−1 (related to disorder) and ~1600 cm−1 (related to sp2‐hybridized carbon in general).
Comparative study on the adsorption characteristics of a triazine‐Si hybrid polymer adsorbent and the natural adsorbents for removal of methylene blue from industrial wastewaters
Authors: Zargoosh Kiomars , Ashrafzade Sheida , Afshari Mohaddeseh , Dinari Mohammad , Moradi Aliabadi Hossein
Published: May 2022

This work aims to compare the practical ability of the novel triazine‐based polymer adsorbents (TBPA‐Si hybrid polymer) with those of the natural adsorbents for the adsorption of methylene blue (MB) from the industrial wastewaters. In this regard, a new TBPA‐Si hybrid polymer includes SH, NH, and aromatic ring functional groups for effective interactions with a wide range of organic pollutants was synthesized. In addition, pine leaves, soybean meal (SBM), and wheat bran were selected as representative of the well‐known natural adsorbents. The optimum pH values for natural adsorbents and TBPA‐Si for MB adsorption were 7 and 8, respectively. The optimum time for wheat bran and TBPA‐Si to reach the maximum MB adsorption was 15 min and for pine leaves and SBM was 5 min. The isotherm data for TBPA‐Si hybrid was well fitted to Langmuir isotherm. Pine leaves showed a mix of Langmuir and Temkin isotherms. In addition, SBM and wheat bran also showed Temkin isotherm. During the kinetics investigations, the pseudo‐second‐order kinetics models were observed for all adsorbents. The maximum adsorption capacities for TBPA‐Si and pine leaves were 15.3 and 32.1 mg.g−1, respectively. The empirical adsorption capacity for SBM and wheat brans were 71.6 and 38.3 mg.g−1, respectively. The key advantage of the TBPA‐Si is its ability for removing MB in the presence of high concentrations of electrolytes, where the removal efficiencies of the natural adsorbent were extremely reduced in these conditions. The main advantage of the natural adsorbents is their low cost for removal of MB from the effluents containing very low concentration of electrolytes.
Low cross‐linked polyimide aerogel with imidazole for CO2 adsorption
Authors: Gao Yangfeng , Dong Chao , Zhang Fan , Ma Hongwei , Li Yang
Published: May 2022

In this study, low cross‐linked mesoporous polyimide aerogels with imidazole were successfully synthesized by co‐polymerization method at room temperature from DMBZ, ABIA, PMDA, and TAB. This synthesis method is milder than previous that of porous material synthesis. The experimental results show that polyimide aerogel with imidazole is a mesoporous material. The thermal decomposition temperatures of obtained polyimide aerogels are all above 450°C, which exhibited outstanding thermal stability. The microscopic morphology varies with the ratio of DMBZ/ABIA monomers. The specific surface area of polyimide aerogel tends to increase first and then decrease with the increase of ABIA content. The largest specific surface area is 240.87 m2/g. However, polyimide aerogel with high specific surface area had not high CO2 adsorption. In contrast, the PAPI‐4 sample with smaller specific surface area had higher CO2 adsorption. The maximum CO2 adsorption capacity is 14.20 cm3/g, which is comparable to those of previously reported porous organic polymers. This suggests that polyimide aerogel can be used as an adsorbent material. The high CO2 adsorptions may be attributed to the abundance of nitrogen‐rich heteroatoms in the polyimide networks.
Coupled CFD‐DEM modeling to predict how EPS affects bacterial biofilm deformation, recovery and detachment under flow conditions
Authors: Xia Yuqing , Jayathilake Pahala G. , Li Bowen , Zuliani Paolo , Deehan David , Longyear Jennifer , Stoodley Paul , Chen Jinju
Published: May 2022

The deformation and detachment of bacterial biofilm are related to the structural and mechanical properties of the biofilm itself. Extracellular polymeric substances (EPS) play an important role on keeping the mechanical stability of biofilms. The understanding of biofilm mechanics and detachment can help to reveal biofilm survival mechanisms under fluid shear and provide insight about what flows might be needed to remove biofilm in a cleaning cycle or for a ship to remove biofilms. However, how the EPS may affect biofilm mechanics and its deformation in flow conditions remains elusive. To address this, a coupled computational fluid dynamic– discrete element method (CFD‐DEM) model was developed. The mechanisms of biofilm detachment, such as erosion and sloughing have been revealed by imposing hydrodynamic fluid flow at different velocities and loading rates. The model, which also allows adjustment of the proportion of different functional groups of microorganisms in the biofilm, enables the study of the contribution of EPS toward biofilm resistance to fluid shear stress. Furthermore, the stress–strain curves during biofilm deformation have been captured by loading and unloading fluid shear stress to study the viscoelastic properties of the biofilm. Our predicted emergent viscoelastic properties of biofilms were consistent with relevant experimental measurements.
Tolerability and efficacy of durvalumab, either as monotherapy or in combination with tremelimumab, in patients from Asia with advanced biliary tract, esophageal, or head‐and‐neck cancer
Authors: Doki Yuichiro , Ueno Makoto , Hsu Chih‐Hung , Oh Do‐Youn , Park Keunchil , Yamamoto Noboru , Ioka Tatsuya , Hara Hiroki , Hayama Manabu , Nii Masahiro , Komuro Keiko , Sugimoto Mariko , Tahara Makoto
Published: May 2022

Background

Agents targeting the programmed cell death‐1 pathway have demonstrated encouraging activity across multiple solid tumor types. The dose expansion phase of this phase I study evaluated the safety, tolerability, and antitumor activity of durvalumab monotherapy, and durvalumab plus tremelimumab (an anti‐cytotoxic T‐lymphocyte‐associated antigen 4 monoclonal antibody) combination therapy, in patients from Asia with biliary tract cancer (BTC), esophageal squamous cell carcinoma (ESCC), or head and neck squamous cell carcinoma (HNSCC).

Methods

Patients with advanced BTC, ESCC, or HNSCC with disease progression during or following ≥1 platinum‐based therapy received durvalumab monotherapy (10 mg/kg every 2 weeks) or durvalumab plus tremelimumab (durvalumab 20 mg/kg every 4 weeks [Q4W] plus tremelimumab 1 mg/kg Q4W for 4 doses, followed by durvalumab 20 mg/kg Q4W). The primary objective was safety and tolerability. Secondary objectives included antitumor activity.

Results

Durvalumab monotherapy was assessed in 116 patients (median age 63.5 years, 75.9% male) of whom, 42, 42, and 32 had BTC, ESCC, or HNSCC, respectively. Grade ≥3 treatment‐related adverse events (TRAEs) were reported in 19.0%, 9.5%, and 25.0% of patients with BTC, ESCC, and HNSCC, respectively. Objective response rate (ORR) was 4.8%, 7.1%, and 9.4% in BTC, ESCC, and HNSCC. Durvalumab plus tremelimumab was evaluated in 124 patients (median age 62.0 years, 79.8% male) of whom 65 had BTC and 59 had ESCC. Grade ≥3 TRAEs were reported in 23.1% and 13.6% of patients with BTC and ESCC. ORR was 10.8% and 20.3% in BTC and ESCC. There were two complete responses and 10 partial responses in ESCC, and seven partial responses in BTC.

Conclusion

In general, durvalumab monotherapy and durvalumab plus tremelimumab combination therapy displayed acceptable safety profiles consistent with published literature, and also demonstrated clinical benefit, in patients from Asia with BTC, ESCC, or HNSCC with disease progression on ≥1 prior treatment. ClinicalTrials.gov Identifier: NCT01938612.
Co‐Binding of JQ1 and Venetoclax Exhibited Synergetic Inhibitory Effect for Cancer Therapy; Potential Line of Treatment for the Waldenström Macroglobulinemia Lymphoma
Authors: Elamin Ghazi , Aljoundi Aimen , Soliman Mahmoud E. S.
Published: May 2022

In recent times, the development of combination therapy has been a focal point in drug discovery. This article explores the potential synergistic effect of co‐administration of Bcl2 inhibitor Venetoclax and BET inhibitor JQ1. We envisioned that the ‘dual‐site’‐binding of Bcl2 has significant prospects and paves the way for the next round of rational design of potent Waldenström macroglobulinemia (WM) therapy. The preferential binding mechanisms of the multi‐catalytic sites of the Bcl2 enzyme have been a subject of debate in the literature. This study conducted a systematic procedure to explore the preferred binding modes and the structural effects of co‐binding at each catalytic active site. Interestingly, a mutual enhanced binding effect was observed – Venetoclax increased the binding affinity of JQ1 by 11.5 %, while JQ1 boosted the binding affinity of Venetoclax by 16.3 % when compared with individual inhibition of each drug. This synergistic binding effect has significantly increased protein stability, with substantial correlated movements and multiple van der Waals interactions. The structural and thermodynamic insights unveiled in this report would assist the future design of improved combined therapy against WM.
Cerebral protection during percutaneous intervention for left ventricular assist device outflow graft obstruction
Authors: Joury Abdulaziz , Patel Rajan A. G. , Wever‐Pinzon James , Eiswirth Clement , Desai Sapna , Bansal Aditya , Krim Selim R.
Published: May 2022

Background

Left ventricular assist devices (LVAD) outflow graft obstruction is an uncommon complication but carries significant morbidity and mortality. Here we provide a case series of patients with LVAD intrinsic outflow graft obstruction who are deemed to be a high surgical risk for pump exchange and, therefore, underwent percutaneous intervention with the concomitant use of neuroprotective device—Sentinel cerebral protection system (CPS) (Boston Scientific) to prevent embolic stroke.

Methods

We retrospectively analyzed patients who underwent LVAD placement in our institution and developed LVAD outflow graft obstruction. The diagnosis of LVAD outflow graft obstruction was confirmed by utilizing various cardiac imaging modalities such as echocardiography and/or computed tomography angiography. All patients were treated with percutaneous intervention and a catheter‐based CPS.

Results

From a total of 501 LVAD implants in our institute, 6 (1.2%) patients with LVAD outflow graft obstruction who underwent percutaneous treatment were included; 4 patients with HeartMate‐III LVAD, 1 patient with HeartMate‐II LVAD, and 1 patient with HeartWare (HVAD). The median age of patients was 56.5 years at the time of LVAD implantation. The median time from the LVAD implantation to the episode of LVAD outflow obstruction was 1343 days. Utilization of Sentinel CPS resulted in the capture and removal of thrombus/debris in all patients.

Conclusions

Percutaneous intervention of LVAD outflow graft obstruction is less invasive than surgical pump exchange and an acceptable alternative in properly selected patients. In our experience, utilization of a catheter‐based CPS can help in reducing the incidence of periprocedural embolic events.
Intramolecular (4+3) Cycloadditions of Oxidopyridinium Ions: Towards Daphnicyclidin A
Authors: Tu Jianzhuo , Ripa Rawshan A. , Kelley Steven P. , Harmata Michael
Published: May 2022

N‐alkylation of 5‐hydroxynicotinic acid esters with electrophiles containing diene functionality produces salts that undergo intramolecular (4+3) cycloaddition reactions upon heating in the presence of base. Initial studies used a three‐carbon tether to join the pyridinium ion and diene, revealing some aspects of the inherent selectivity of the reaction with such substrates. Much more challenging was the synthesis of related species possessing only a two‐carbon tether. Nevertheless, the cycloaddition of such compounds was successful, leading directly to the ABC ring system of the alkaloid daphnicyclidin A.