bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal Tolerance and Clearance Allocation in Mechanisms to Minimize Manufacturing Cost
Authors: Biswas Arunava , Kinzel Gary L.
Published: February 2021

A procedure has been developed for the optimal allocation of tolerances and clearances in complex assemblies. The objective is to minimize manufacturing costs and sensitivity to variations in the design variables. The assemblies considered are single loop planar and spatial mechanisms including those with analytically defined surface contact joints. The procedure, to be used in early design stages, allows the incorporation of manufacturing tolerances and clearances based on actual manufacturing process and cost information. This allows the designer’s intent and the manufacturing and process capabilities to be tied together in the development of the product or assembly. The allocation of tolerances is done with the idea of minimizing the overall “life cycle cost” of the assembly, which not only involves the actual manufacturing cost but also the cost involved in maintaining the design variables within tolerable values. A multicriteria optimization procedure is used to handle the two aforementioned conflicting objectives. The kinematic analysis of mechanisms with clearance joints is performed using an iterative procedure along with an equivalent “clearance link” model.
Linkage Synthesis of a Four-Bar Mechanism for N Precision Points Using Simulated Annealing
Authors: Martínez-Alfaro Horacio , Valdez Homero , Ortega Jaime
Published: February 2021

This paper presents an alternative way of linkage synthesis by using a computational intelligence technique: Simulated Annealing. The technique allows to define n precision points of a desired path to be followed by a four-bar linkage (path generation problem). The synthesis problem is transformed into an optimization one in order to use the Simulated Annealing algorithm. With this approach, a path can be better specified since the user will be able to provide more “samples” than the usual limited number of five allowed by the classical methods. Several examples are shown to demonstrate the advantages of this alternative synthesis technique.
Size and Shape Optimization of Compliant Mechanisms: An Efficiency Formulation
Authors: Hetrick Joel A. , Kota Sridhar
Published: February 2021

Compliant mechanisms are jointless mechanical devices that take advantage of elastic deformation to achieve a force or motion transformation. A milestone toward systematic design of compliant mechanisms has been the development of topology optimization techniques. The next logical step is to incorporate size and shape optimization to identify the exact dimensional form of the mechanism. A new objective formulation based on maximizing the mechanical efficiency of a compliant mechanism is developed in order to perform the size and shape optimization. An advantage of this formulation is that precise control over the mechanism’s mechanical or geometric advantage can be enforced during optimization. Finite element beam models are used to perform dimensional synthesis of planar compliant mechanisms. This technique allows stress constraints to limit the maximum stress in the mechanism which improves the mechanism’s durability and flexibility. Resulting optimized mechanisms exhibit efficient mechanical transmission and meet kinematic and stress requirements. Several examples are given to demonstrate the effectiveness of the optimization procedure.
A Multi-Criteria Optimization Method for Mechanism Tolerance and Clearance Design
Authors: Biswas Arunava , Kinzel Gary L.
Published: February 2021

A procedure has been developed for optimally allocating tolerances and clearances in single loop planar and spatial mechanisms for minimum cost and minimum sensitivity to parameter variations. The cost of incorporating individual tolerances and clearances using specific manufacturing processes and their overall effects (sensitivities) on the whole assembly is established for each individual part. These are then incorporated into a multicriteria nonlinear optimization procedure to obtain the best tolerance and clearance specification for a part and the best manufacturing process. The procedure is developed for use in the early design stages of an assembly to allow the design to accommodate dimensional variations occurring during overall life cycle of the mechanism. The design is made as insensitive as possible to these variations, i.e. “robust” against the manufacturing and operating variations.
Automated Synthesis and Optimization of Robot Configurations
Authors: Leger Chris , Bares John
Published: February 2021

We present an extensible system for synthesizing and optimizing robot configurations. The system uses a flexible representation for robot configurations based on parameterized modules; this allows us to synthesize mobile and fixed-base robots, including robots with multiple or branching manipulators and free-flying robots. Synthesis of modular robots is also possible with our representation. We use an optimization algorithm based on genetic programming. A distributed architecture is used to spread heavy computational loads across multiple workstations. We take a task-oriented approach to synthesis in which robots are evaluated on a designer-specified task in simulation; flexible planning and control algorithms are thus required so that a wide variety of robots can be evaluated. Our system’s extensibility stems from an object-oriented software architecture that allows new modules, metrics, controllers, and tasks to be easily added. We present two example synthesis tasks: synthesis of a robotic material handler, and synthesis of an antenna pointing system for a mobile robot. We analyze several key issues raised by the experiments and show several important ways in which the system can be extended and improved.
A Simple Finite Element Based Model for a Constrained-Layer of Viscoelastic Material: Part 1 — Experimental Verification and Comparison With Analytical Models
Authors: Sisemore Carl , Smaili Ahmad
Published: February 2021

In this article, a simple, finite element based model for a constrained layer of viscoelastic damping for beams is developed and implemented. The proposed model uses a series of discrete springs and dampers to model the stiffness and damping, and lumped masses to account for the mass of the viscoelastic material while the base material and constraining layers are modeled with a five-node Timoshenko beam element. The accuracy of the model is verified experimentally by testing damped beams with various damping treatment configurations. The results from the proposed model and the experiments are then compared with the Mead-Markus analytical model. Concerns over the accuracy of the Mead-Markus analytical model are raised and discussed. The results demonstrate that the proposed model can predict the fundamental natural frequency of damped beams to within 3.5% or better of the experimentally determined values and that, with the exception of short and intermediate length constraining layers, the damping ratio can be predicted to within about 8% of the experimental values under most circumstances.
A Parallely Actuated Work Support Module for Reconfigurable Machining Systems
Authors: Gopalakrishnan Venkat , Kota Sridhar
Published: February 2021

In order to respond quickly to changes in market demands and the resulting product design changes, machine tool manufacturers must reduce the machine tool design lead time and machine set-up time. Reconfigurable Machine Tools (RMTs), assembled from machine modules such as spindles, slides and worktables are designed to be easily reconfigured to accommodate new machining requirements. The essential characteristics of RMTs are modularity, flexibility, convertibility and cost effectiveness. The goal of Reconfigurable Machining Systems (RMSs), composed of RMTs and other types of machines, is to provide exactly the capacity and functionality, exactly when needed. The scope of RMSs design includes mechanical hardware, control systems, process planning and tooling.

One of the key challenges in the mechanical design of reconfigurable machine tools is to achieve the desired machining accuracy in all intended machine configurations. To meet this challenge we propose (a) to distribute the total number of degrees of freedom between the work-support and the tool and (b) employ parallely-actuated mechanisms for stiffness and ease of reconfigurability. In this paper we present a novel parallely-actuated work-support module as a part of an RMT. Following a brief summary of a few parallel mechanisms used in machine tool applications, this paper presents a three-degree-of-freedom work-support module designed to meet the machining requirements of specific features on a family of automotive cylinder heads. Inverse kinematics, dynamic and finite element analysis are performed to verify the performance criteria such as workspace envelope and rigidity. A prototype of the proposed module is also presented.
Partial Contact Force Controllability in Active Wheeled Vehicles
Authors: Choi B. J. , Sreenivasan S. V.
Published: February 2021

This paper presents a geometric approach for solving the force distribution problem in active wheeled vehicles (AWVs) moving on even and uneven surfaces. In general, AWVs do not possess omni-directional mobility and they do not have sufficient actuators to directly control all the components of the wheel-ground contact forces. This situation requires the separation of the contact force vectors into active and passive components. An optimal contact force allocation algorithm can then be developed for these systems. The concepts introduced in this article are demonstrated via simple planar examples and by using an active off-road vehicle with slip-free motion capability. Off-road kinematic/static simulations of AWVs and force controlled legged vehicles (FCLVs) are presented and a comparison of these results provides interesting insight into partial force controllability characteristics of AWVs.
Calculation of Wobble From Lead Inspection Data of Gear Teeth With Modifications
Authors: Su Xiaogen , Houser Donald R.
Published: February 2021

The effect of the reference misalignment including eccentricity and wobble on profile and lead inspection traces is discussed. The relative slopes of the lead traces induced by wobble are used to calculate the magnitude of the wobble. The deviation caused by the wobble is removed from the lead inspection results. This method is theoretically ‘exact’ for spur gears and is approximate for helical gears. Real measurement examples show this method produces a good result with a spur gear and a satisfactory result with a helical gear.
Pitting Life of Ground, Carburized and Hardened Gears With Uncontrolled Heat Treat Distortion
Authors: Rakhit A. K.
Published: February 2021

Carburized and hardened gears are generally ground to improve the quality of distorted tooth geometry caused by heat treatment. As long as the distortion is low and predictable, stock removal from teeth is small up to a maximum of 0.005 inch from each flank. This allows minimum tooth surface hardness reduction with no deterioration of these gears. Uncontrolled distortion, on the other hand, may result in an undue amount of stock removal with a significant loss of tooth surface hardness. Lower surface hardness reduces gear life due to tooth pitting. For heavily distorted gears, the pitting life may be reduced as much as 30% after grinding. For a realistic evaluation of the pitting life of ground, carburized gears with uncontrolled distortion, derating factors are established for a number of gear materials.
Russian academy probe triggers more than 800 retractions
Authors: Chawla Dalmeet Singh
Published: February 2021

Fraud commission's work causes "tension and conflict."
Need for speed
Authors: Stone Richard
Published: February 2021

Despite hype and technological hurdles, a hypersonic arms race is accelerating.
Tolerance to antibiotics affects response
Authors: Berti Andrew D. , Hirsch Elizabeth B.
Published: February 2021

Bacterial tolerance to antibiotics reduces the ability to prevent resistance
Depression, anxiety and stress among patients with inflammatory bowel disease during the COVID-19 pandemic: Australian national survey
Authors: Cheema Madiha , Mitrev Nikola , Hall Leanne , Tiongson Maria , Ahlenstiel Golo , Kariyawasam Viraj
Published: February 2021

Background

The global COVID-19 pandemic has impacted on the mental health of individuals, particularly those with chronic illnesses. We aimed to quantify stress, anxiety and depression among individuals with Inflammatory bowel disease (IBD) in Australia during the pandemic.

Methods

An electronic survey was made available to IBD patients Australia-wide from 17 June to 12 July 2020. Respondents with an underlying diagnosis of IBD and over 18 years of age were included. A validated questionnaire (Depression, Anxiety, Stress Score-21, DASS21) was used to assess depression, anxiety and stress. Data on potential predictors of depression, anxiety and stress were collected.

Results

352 participated in the survey across Australia. 60.5% of respondents fulfilled DASS criteria for at least moderate depression, anxiety or stress. 45% reported a pre-existing diagnosis of depression and/or anxiety. Over 2/3 of these respondents reported worsening of their pre-existing depression/anxiety due to the current pandemic. Of those without a pre-existing diagnosis of anxiety or depression, high rates of at least moderate to severe depression (34.9%), anxiety (32.0%) and stress (29.7%) were noted. Younger age (OR 0.96, 95% CI 0.94 to 0.98, p<0.001), lack of access to an IBD nurse (OR 1.81, 95% CI 1.03 to 3.19, p=0.04) and lack of education on reducing infection risk (OR 1.99, 95% CI 1.13 to 3.50, p=0.017) were associated with significant stress, anxiety and/or depression.

Conclusion

High prevalence of undiagnosed depression, anxiety and stress was identified among respondents. Improved access to IBD nurse support and greater attention to education are modifiable factors that may reduce depression, anxiety and/or stress among patients with IBD during the pandemic.
Weight loss with exercise improves muscle architecture and progenitor cell populations compared to weight loss alone in mice with preneoplastic colorectal lesions
Authors: Roubos Sophia , D’Souza Donna , Hernández-Saavedra Diego , Xu Guanying , Collao Nicolas , Emmons Russell , Larkin Jillian , Lloyd Jessica , Vanhie James J. , Pan Yuan-Xiang , Chen Hong , De Lisio Michael
Published: February 2021

Weight loss and exercise reduce colorectal cancer (CRC) risk in persons with obesity. Whether weight loss and exercise effect myofibre characteristics and muscle stem/progenitor cell populations in mice with preneoplastic colorectal lesions, a model of CRC risk, is unknown. To address this gap, male C57Bl/6J mice were fed a high-fat diet (HFD) to induce obesity or a control (CON) diet prior to azoxymethane injection to induce preneoplastic colorectal lesions. The HFD group was then randomized to weight loss conditions that included (1) switching to the CON diet only (HFD-SED) or switching to the CON diet with treadmill exercise training (HFD-EX). Average myofibre cross-sectional area was not different between groups. There were more smaller-sized fibers in HFD-EX (p<0.05 vs. CON), and more fibrosis in HFD-SED (p<0.05 vs. HFD-EX and CON). There was a trend for more committed (Pax7+MyoD+) myoblasts (p=0.059) and more fibro-adipogenic progenitors (FAPs) in HFD-EX (p<0.05 vs. CON). Additionally, the canonical pro-inflammatory marker p-NF-κB, was markedly reduced in the insterstitium of HFD-EX (p<0.05 vs. CON and HFD-SED). Our findings suggest that in mice with preneoplastic colorectal lesions, HFD followed by weight loss with exercise, reduces muscle fibrosis and results in a higher content of muscle stem/progenitor cells.
Novelty Bullets:
• Exercise improves muscle architecture in mice with preneoplastic colorectal lesion
• Exercise increases fibro/adipogenic progenitors and reduces inflammatory signaling in mice with preneoplastic colorectal lesions
Striking muscle adaptations induced by volume-dependent repeated bouts of low-intensity eccentric exercise of the elbow flexors
Authors: Chen Trevor C. , Tseng Wei-Chin , Chen Hsin-Lian , Tseng Kuo-Wei , Chou Tai-Ying , Huang Yuh-Chuan , Nosaka Kazunori
Published: February 2021

We investigated the effects of repeating 30 low-intensity eccentric contractions with a dumbbell corresponding to 10% maximal isometric strength (10%EC) on muscle strength and hypertrophy, and muscle damage after 30 maximal eccentric contractions (MaxEC) of the elbow flexors. Young men were placed into 1 of 3 experimental groups that performed 10%EC either once, twice a week for 4 (8 bouts) or 8 weeks (16 bouts) before MaxEC, or a control group that performed 2 bouts of MaxEC separated by 2 weeks (n = 13/group). Repeating 16 bouts of 10%EC increased (P < 0.05) maximal voluntary contraction strength (30 ± 21%) and muscle thickness (4.2 ± 2.3%) greater than 8 bouts (16 ± 4%, 1.9 ± 1.3%). Changes in the muscle damage markers after MaxEC were smaller (P < 0.05) for the experimental groups than the control group, and the magnitude of muscle damage protection was greater (P < 0.05) after 16 bouts (65 ± 30%) than 8 bouts (55 ± 33%), followed by 1 bout (34 ± 27%). The protection by 16 bouts was similar (P = 0.81) to that shown by the second MaxEC of the control group. These results showed that 10%EC produced potent muscle adaptation effects accumulatively and conferred muscle damage protection, but 1 bout of 10%EC was still effective for conferring approximately 20% of the protection of that by 16 bouts.

Novelty: Repeating low-intensity eccentric exercise induces large increases in muscle strength and hypertrophy. Low-intensity eccentric exercise protects muscle damage induced by maximal eccentric contractions, and the protection is reinforced by repeating it. These are especially beneficial for individuals who are frail and cannot tolerate high-intensity resistance training.
Neural Networks with Emotion Associations, Topic Modeling and Supervised Term Weighting for Sentiment Analysis
Authors: Hajek Petr , Barushka Aliaksandr , Munk Michal
Published: February 2021

Automated sentiment analysis is becoming increasingly recognized due to the growing importance of social media and e-commerce platform review websites. Deep neural networks outperform traditional lexicon-based and machine learning methods by effectively exploiting contextual word embeddings to generate dense document representation. However, this representation model is not fully adequate to capture topical semantics and the sentiment polarity of words. To overcome these problems, a novel sentiment analysis model is proposed that utilizes richer document representations of word-emotion associations and topic models, which is the main computational novelty of this study. The sentiment analysis model integrates word embeddings with lexicon-based sentiment and emotion indicators, including negations and emoticons, and to further improve its performance, a topic modeling component is utilized together with a bag-of-words model based on a supervised term weighting scheme. The effectiveness of the proposed model is evaluated using large datasets of Amazon product reviews and hotel reviews. Experimental results prove that the proposed document representation is valid for the sentiment analysis of product and hotel reviews, irrespective of their class imbalance. The results also show that the proposed model improves on existing machine learning methods.
A comparison of calculated β-decay half-lives with photonuclear reaction data and other experiments
Authors: Aygor H. A. , Cakmak N. , Almaz E. , Unlu S.
Published: February 2021

We try to give a comparison of the calculated Gamow–Teller [Formula: see text]-decay half-lives for [Formula: see text], [Formula: see text] and [Formula: see text] nuclei with the experimental ones obtained from ([Formula: see text],p), ([Formula: see text],n) and (n,[Formula: see text]) reactions, respectively. The calculations are performed within the framework of quasi-particle phonon nuclear model. The nucleon–nucleon interaction potential is included according to Pyatov’s restoration method. The calculated decay half-lives are also compared with available experimental data in the literature.
A numerical method based on three-dimensional Legendre wavelet method for two-dimensional time-fractional diffusion equation
Authors: Abdi Sarkout , Azizi Aram , Shafiee Mahmoud , Saeidian Jamshid
Published: February 2021

In this paper, an efficient numerical method is proposed to handle two-dimensional fractional diffusion equations on a finite domain. The proposed method combines the product of Legendre wavelet bases for two spatial dimensions and a time direction. The operational matrix of the proposed method is obtained. Tikhonov regularization is employed to stabilize the system in cases where the final linear system of equations is large. The convergence analysis of the method is studied and some numerical examples are presented to investigate the efficiency and accuracy of the method.
Editors’ Choice—Necessity to Avoid Titanium Oxide as Electrocatalyst Support in PEM Fuel Cells: A Membrane Durability Study
Authors: Zhang Jingxin , Coms Frank , Kumaraguru Swami
Published: February 2021

Pt/TiO2 as electrocatalyst was found to significantly increase the rate of the membrane chemical degradation in a polymer electrolyte membrane (PEM) fuel cell. The increased degradation was proved to be due to TiOx (TiO2 or Ti4O7), which is widely recognized as a promising corrosion-resistant electrocatalyst support. The membrane degradation (thinning) appears to be preferentially in the side facing anode electrode. Migrated Ti species as a result of TiOx dissolution during fuel cell operation in an acidic environment was quantified by electron probe microanalysis (EPMA). Total fluorine inventory loss of the membrane strongly depends on the quantity of migrated Ti species (likely Ti3+ and/or Ti4+). The membrane chemical degradation induced by TiOx is proposed to be due to dissolved ionic Ti species reacting with H2O2 through a Fenton reaction. TiOx is determined to be inviable as electrocatalyst support for PEM fuel cells, and future research is suggested to be directed toward alternative oxides with similar corrosion-resistance.
Research on Energy Conversion and Damage Features of Unloading Instability of Sandstone under High Stress
Authors: Hou Zhiyuan , Hao Chuanbo , Xiao Fukun , Liu Gang
Published: February 2021

In order to explore the failure characteristics of sandstone under unloading conditions in deep zone with high stress, constant axial pressure and unloading confining pressure tests were conducted on a yellow sandstone sample under different initial confining pressures using the French ROCK600‐50 triaxial tester, and the mechanical properties, energy conversion characteristics, and damage evolution law of sandstone failure under unloading conditions were obtained. The test results showed that the axial deformation, the confining pressure for failure, and the shear fracture energy during the failure process of sandstone under the unloading state were positively correlated with the initial confining pressure; the dilatancy amount and speed and the radial deformation were negatively correlated with the initial confining pressure, exhibiting the characteristics of dilatancy under low confining pressure and compression under high confining pressure. Before the unloading point, almost all the energy absorbed by the rock under low initial confining pressure was converted into elastic energy, while part of the energy absorbed under high initial confining pressure was converted into dissipated energy, and the higher the confining pressure, the greater the proportion of the dissipated energy converted. The higher the initial confining pressure, the greater the elastic energy, radial deformation energy, and dissipated energy at the rock fracture point. The larger the unloading confining pressure, the greater the postpeak failure energy and surplus energy of sandstone, and the greater the increase in the proportion of elastic energy converted into surplus energy. The higher the confining pressure, the larger the damage value at the unloading point; the damage speed in the unloading stage was significantly greater than that in the loading stage.
Using Hybrid Artificial Intelligence Approaches to Predict the Fracture Energy of Concrete Beams
Authors: Xiao Qinghua , Li Congming , Lei Shengxiang , Han Xiangyu , Chen Qiaofeng , Qiu Zemin , Sun Biao
Published: February 2021

Fracture energy is always used to represent the fracture performance of concrete structures/beams, which is crucial for the application of concrete. However, due to the nature of concrete material and the complexity of the fracture process, it is difficult to accurately determine the fracture energy of concrete and predict the fracture behavior of different concrete structures. In this study, artificial intelligence approaches were tried to seek a feasible way to solve these prediction issues. Firstly, the ridge regression (RR), the classification and regression tree (CART), and the gradient boosting regression tree (GBRT) were selected to construct the predictive models. Then, the hyperparameters were tuned with the particle swarm optimization (PSO) algorithm; the performances of these three optimum models were compared with the test dataset. The mean squared errors (MSEs) of the optimum RR, CART, and GBRT models were 0.0447, 0.0164, and 0.0111, respectively, which indicated that their performances were excellent. Compared with the RR and CART models, the hybrid model constructed with GBRT and PSO appeared to be the most accurate and generalizable, both of which are significant for prediction work. The relative importance of the variables that influence the fracture energy of concrete was obtained, and compressive strength was found to be the most significant variable.
Clinical Trial of Allogeneic Mesenchymal Stem Cell Therapy for Chronic Active Antibody-Mediated Rejection in Kidney Transplant Recipients Unresponsive to Rituximab and Intravenous Immunoglobulin
Authors: Ban Tae Hyun , Lee Sua , Kim Hyung Duk , Ko Eun Jeong , Kim Bo-Mi , Kim Kyoung-Woon , Chung Byung Ha , Yang Chul Woo
Published: February 2021

Clinical trials of biologic agents for chronic active antibody-mediated rejection (CAMR) in kidney transplant recipients (KTRs) have been disappointing. We performed a clinical trial of mesenchymal stem cell (MSC) treatment in KTRs with CAMR unresponsive to rituximab and intravenous immunoglobulin. This study was a phase 1 clinical trial to confirm patient safety. Two patients with CAMR unresponsive to rituximab and intravenous immunoglobulin were included. Each patient received allogeneic MSCs for 4 cycles (

1
×

10

6

cells/kg every other week) via the peripheral vein in the distal arm. We observed adverse events and renal function for 6 months after the final MSC infusion and analyzed changes in immunomodulatory parameters in the peripheral blood between the start of treatment and 3 months after the final MSC infusion. There were no serious adverse events during the study period. Renal function was stable during MSC treatment but gradually decreased between the final MSC infusion and the study endpoint (patient 1: creatinine levels ranged from 3.01 mg/dL to 7.81 mg/dL, patient 2: 2.87 mg/dL to 3.91 mg/dL). In peripheral blood sample analysis between the start of treatment and 3 months after the final MSC infusion, there were similar trends for immunomodulatory markers. Our study showed that there were no serious adverse events for six months after allogeneic MSC treatment in KTRs with CAMR refractory to rituximab and intravenous immunoglobulin, but further studies need to define the efficacy of MSC treatment in CAMR.
Impaired Limb Functional Outcome of Peripheral Nerve Regeneration Is Marked by Incomplete Recovery of Paw Muscle Atrophy and Brain Functional Connectivity in a Rat Forearm Nerve Repair Model
Authors: Bao Qiyuan , Liu Qi , Wang Jun , Shen Yuhui , Zhang Weibin
Published: February 2021

Skilled sensorimotor deficit is an unsolved problem of peripheral nerve injury (PNI) led by limb trauma or malignancies, despite the improvements in surgical techniques of peripheral nerve anastomosis. It is now accepted that successful functional recovery of PNI relies tremendously on the multilevel neural plasticity from the muscle to the brain. However, animal models that recapitulate these processes are still lacking. In this report, we developed a rat model of PNI to longitudinally assess peripheral muscle reinnervation and brain functional reorganization using noninvasive imaging technology. Based on such model, we compared the longitudinal changes of the rat forepaw intrinsic muscle volume and the seed-based functional connectivity of the sensorimotor cortex after nerve repair. We found that the improvement of skilled limb function and the recovery of paw intrinsic muscle following nerve regeneration are incomplete, which correlated with the functional connectivity between the primary motor cortex and dorsal striatum. Our results were highly relevant to the clinical observations and provided a framework for future investigations that aim to study the peripheral central sensorimotor circuitry underlying skilled limb function recovery after PNI.
Investigation of the Performance of Ceramic Fiber Modified Asphalt Mixture
Authors: Wang Xiushan , Zhou Hengyu , Hu Xingxing , Shen Senjie , Dong Bowen
Published: February 2021

Ceramic fiber (CF) is a novel thermally resistant material with the potential to improve the high‐temperature performance of asphalt mixture. In this study, asphalt mixtures with 0%, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% CFs were prepared. The Marshall test, wheel tracking test, Marshall immersion test, freeze‐thaw splitting test, and low‐temperature bending test were conducted to evaluate the performance of the CF‐modified asphalt mixture. The morphologies of these asphalt mixtures were observed using scanning electron microscopy to analyze the modification mechanism. The results showed that the CFs could improve the mechanical properties, high‐temperature stability, moisture susceptibility, and low‐temperature cracking resistance of asphalt mixture, with the optimum CF content being 0.4%. Further microscopic analysis showed that the CFs improved the performances of asphalt mixture through forming three‐dimensional network structure, asphalt absorption, bridging cracks, and pulling‐out effect.
Survival Analysis of Radiation Therapy in Ovarian Cancer: A SEER Database Analysis
Authors: Yu Lushi , Gong Hongyun , Li Qian , Ren Honggang , Wang Yi , He Haihua , Li Tian , Song Qibin
Published: February 2021

Background and purpose. A large sample size study on survival analysis of radiotherapy in ovarian cancer is deficient. This study aimed to explore the survival impact of radiotherapy in ovarian cancer. Materials and methods. Data of patients diagnosed with ovarian cancer between 2010 and 2015 were collected from Surveillance, Epidemiology, and End Results (SEER) Database. Survival comparisons were analyzed using Kaplan–Meier analysis and log-rank tests. Univariate and multivariate Cox regression analyses were used to select predictors associated with survival. Propensity score matching (PSM) analysis was employed to balance baseline variables. Results. A total of 20031 ovarian cancer patients were included, with 291 (1.45%) patients who received radiotherapy. The median overall survival (OS) in patients who received radiotherapy was shorter than which in patients without radiotherapy (23 vs. 75 months,

P
<
0.001

). The Elderly, nonepithelial pathology, advanced American Joint Committee on Cancer (AJCC) stage, elevated level of CA125, and receiving radiotherapy were risk predictors to survival in both multivariable analyses before and after PSM. Among 11872 patients with III/IV stage, the radiotherapy group also showed a significantly worse prognosis (median OS: 19 vs. 44 months in patients without radiotherapy,

P
<
0.001

). Consistent results were observed in stratification analyses on pathology and stage among patients with III/IV stage. Conclusions. For patients with ovarian cancer, radiotherapy was associated with a poor prognosis regardless of pathology or stage. Considering this is a retrospective study, future studies concerning radiotherapy combination with other new agents in ovarian cancer are needed.
Parastomal Gallbladder Herniation as an Incidental Preoperative Computed Tomography Finding
Authors: Smarda Magdalini , Manes Konstantinos , Fagkrezos Dimitrios , Argiropoulos Dimitrios , Laios Konstantinos , Triantopoulou Charickleia , Maniatis Petros
Published: February 2021

A 65-year-old woman with a long surgical history was referred to our hospital’s Colorectal Unit for ileostomy management. The patient retained an ileostomy for almost a decade after a series of complicated operations she had undergone, which had several side effects such as electrolyte imbalances, high output, weight loss, and a parastomal hernia. Our hospital’s colorectal surgeon proposed to replace the ileostomy with a permanent sigmoidostomy and asked for an imaging evaluation of the parastomal hernia content before the surgery. A computed tomography of the abdomen was performed using our Computed Tomography Department’s 64-detector row CT scanner after oral administration of contrast media, without intravenous contrast media injection due to allergy. Concerning the parastomal ileostomal hernia, besides small bowel loops with intraluminal gastrografin, inside the parastomal hernial sac, there also was an almost rounded cystic lesion. Absence of the gallbladder at its typical position and no record of cholecystectomy raised suspicion for gallbladder projection inside the sac. Our suspicion was confirmed during the surgery. Nonexisting acute cholecystitis allowed easy reduction of the gallbladder along with the small bowel loops inside the peritoneal cavity, without proceeding to cholecystectomy at the same time. Finally, ileostomy was annulated and an end colostomy was established. Four days after the surgery, the patient was discharged from the hospital and was happy to live an almost normal life thereafter.
Intravitreal Aflibercept as a Rescue Therapy for Retinal Neovascularization and Macular Edema due to Eales Disease
Authors: Hsia Ning-Yi , Lin Chun-Ju , Lai Chun-Ting , Bair Henry , Chang Cheng-Hsien , Lin Jane-Ming , Tsai Yi-Yu
Published: February 2021

We report the rescue effect of intravitreal aflibercept injections on retinal neovascularization and macular edema due to Eales disease. Case 1 was a 36-year-old female. Intravitreal aflibercept was administered as rescue therapy after persistent retinal neovascularization following retinal photocoagulation, periocular triamcinolone, and intravitreal ranibizumab injection. Retinal neovascularization initially regressed, but recurred after 5 months along with macular edema. Two more intravitreal aflibercept injections were given, and retinal neovascularization with macular edema regressed. Her vision improved to 20/25 and remained stable after 43 months. Case 2 was a 27-year-old female. Intravitreal aflibercept was administered after persistent retinal neovascularization and macular edema following periocular triamcinolone injection. The macular edema initially subsided but recurred after 3 months. Intravitreal aflibercept injections were then administered once every three months to maintain her vision 20/20. The patient has been followed up for 28 months. Intravitreal aflibercept was effective as a rescue therapy in the treatment of Eales disease to regress retinal neovascularization, though repeated injections were necessary in cases of recurrence.
Targeting PIM1-Mediated Metabolism in Myeloid Suppressor Cells to Treat Cancer
Authors: Xin Gang , Chen Yao , Topchyan Paytsar , Kasmani Moujtaba Y. , Burns Robert , Volberding Peter J. , Wu Xiaopeng , Cohn Alexandra , Chen Yiliang , Lin Chien-Wei , Ho Ping-Chih , Silverstein Roy , Dwinell Michael B. , Cui Weiguo
Published: February 2021

There is a strong correlation between myeloid-derived suppressor cells (MDSC) and resistance to immune checkpoint blockade (ICB), but the detailed mechanisms underlying this correlation are largely unknown. Using single-cell RNA sequencing analysis in a bilateral tumor model, we found that immunosuppressive myeloid cells with characteristics of fatty acid oxidative metabolism dominate the immune-cell landscape in ICB-resistant subjects. In addition, we uncovered a previously underappreciated role of a serine/threonine kinase, PIM1, in regulating lipid oxidative metabolism via PPARγ-mediated activities. Enforced PPARγ expression sufficiently rescued metabolic and functional defects of Pim1−/− MDSCs. Consistent with this, pharmacologic inhibition of PIM kinase by AZD1208 treatment significantly disrupted the myeloid cell–mediated immunosuppressive microenvironment and unleashed CD8+ T-cell–mediated antitumor immunity, which enhanced PD-L1 blockade in preclinical cancer models. PIM kinase inhibition also sensitized nonresponders to PD-L1 blockade by selectively targeting suppressive myeloid cells. Overall, we have identified PIM1 as a metabolic modulator in MDSCs that is associated with ICB resistance and can be therapeutically targeted to overcome ICB resistance.
ДОСЛІДЖЕННЯ ЩОДО СТАНДАРТИЗАЦІЇ ЧОРНИЦІ ПАГОНІВ ЗА ВМІСТОМ ГІДРОКСИКОРИЧНИХ КИСЛОТ
Authors: Vronska L. V.
Published: February 2021

Мета роботи – кількісне визначення гідроксикоричних кислот в ЛРС чорниці пагонів і обґрунтування можливості стандартизації за їхнім вмістом.

Матеріали і методи. Матеріалом для дослідження були дикорослі зразки чорниці пагонів, зібрані у 4 областях України та зразки лікарського засобу чорниці пагонів, придбані в аптеках. Запис електронних спектрів поглинання і вимірювання абсорбції здійснювали на спектрофотометрі Cary 50 UV-Vis (“Agilent Technologies”, США). У дослідженні використовували рідинний хроматограф з діодною матрицею (“Waters 2690”, США), хроматографічну колонку XTerra C18 (“Waters”, США) розміром 250х4,6 мм (5 мкм). Стандартні зразки хлорогенової, ферулової, розмаринової, кофейної кислот (Sigma-Aldrich, Fluka) застосовували для ідентифікації і кількісного визначення.

Результати і обговорення. 15 зразків чорниці пагонів: 7 зразків лікарського засобу промислового виробництва і 8 зразків дикорослої сировини власної заготівлі, досліджено методом ВЕРХ зі спектрофометричним детектуванням в умовах градієнтного елюювання. Встановлено, що кислота хлорогенова є домінуючою сполукою із гідроксикоричних кислот і тому може бути стандартом для перерахунку їхнього вмісту. Кислоти кофейна і/або ферулова ідентифіковані в окремих досліджуваних зразках і їхній вміст є незначним порівняно із вмістом кислоти хлорогенової. Спектрофотометричне визначення суми гідроксикоричних кислот у сировині пагонів чорниці є неможливим через заважаючий вплив флавоноїдів. Вміст кислоти хлорогенової, за результатами ВЕРХ-визначення, у зразках лікарського засобу чорниці пагонів становив – 0,385-0,566%, а в зразках дикорослої сировини – 1,368-1,991%. Високий вміст кислоти хлорогенової у сировині чорниці пагонів та її біологічна активність є аргументом для запровадження нового селективного кількісного показника якості при її стандартизації.

Висновки. ВЕРХ-визначення кислоти хлорогенової може бути запроваджено як кількісний показник якості сировини чорниці пагонів на заміну діючого неселективного показника – визначення вмісту поліфенолів.
China
Authors: Liu Nengye
Published: February 2021

This article examines China’s legislation on distant water fishing as a flag State, which has significant impact on the conservation of marine living resources in the world ocean. After briefly discussing internal and external pressures that the Chinese authorities are facing, the article provides an overview of the latest series of regulations for China’s distant water fishing fleet. It pays particular attention to the adoption of and compliance with the 2020 Rules on the Management of Distant Water Fishing.
The Islamic Port of al-Balīd (Oman), between Land and Sea: Place of Trade, Exchange, Diversity, and Coexistence
Authors: Fusaro Agnese
Published: February 2021

The site of al-Balīd (Southern Oman), identified as the ancient Ẓafār, was a major port city in the Islamic period. Its strategic position and its history, strongly interdependent with that of neighbouring regions, gave it an important socio-economic role.

The abundant ceramics and the rich and diverse archaeological materials recovered at the site prove that al-Balīd has always maintained relationships with people living inland and, at the same time, that it was intensively involved in the Indian Ocean trade. The pottery also reflects the coexistence of different traditions, various social classes, and several communities at al-Balīd.
The Polyvalent Qadamgāh Imām ʿAlī In Hyderabad, Sindh
Authors: Boivin Michel
Published: February 2021

In the early twentieth century, scholars such as I. Goldziher reported that India was characterized by a large number of bodily relics relating to Muḥammad that were venerated. But another issue was ignored: the worship of the footprints of the first Shiʿite Imam, ʿAlī. This contribution offers an analysis of the various political and social issues that the Qadamgāh Imām ʿAlī of Hyderabad, Sindh (Pakistan), has embodied since its installation at the beginning of the nineteenth century.
Morphology and molecular approach reveal a new species of the genus Russula subsect. Lepidinae (Russulaceae) from India
Authors: GHOSH ANIKET , DAS KANAD , CHAKRABORTY DYUTIPARNA
Published: February 2021

Russula baniyakundensis (subg. Russula subsect. Lepidinae), a new species originating from the temperate to subalpine regions of Uttarakhand Himalaya and related to the European R. lepida Fr. is described. The phylogenetic analyses using the internal transcribed spacer (ITS) suggest that in addition to Indian sequences of R. baniyakundensis, there are sequences from China (wrongly labelled as “Russula rosea”) that are also conspecific with R. baniyakundensis in subsect. Lepidinae. Comparison with its respective allied species and a key to the described species of subsect. Lepidinae are provided for a better understanding of its taxonomic position.
microRNA-1296 Inhibits Glioma Cell Growth by Targeting ABL2
Authors: Zhang Gaolian , Xia Meng , Guo Jianhui , Huang Yi , Huang Jianrong , Wei Kecong , Zhang Xiaoning , Zeng Jing , Liang Weibin
Published: February 2021

Aberrant expression of microRNAs (miRNAs) has been reported to play a role in tumorigenesis. Dysfunction of miR-1296 was found in a variety of cancers, however, the function of miR-1296 in the progression of glioma remains largely understood. Here, our results showed that miR-1296 was significantly down-regulated in glioma tissues and cell lines. Decreased expression of miR-1296 was associated with the tumor size, WHO grade and karnofsky performance scale (KPS) of glioma patients. Low expression of miR-1296 was significantly correlated with the shorter 5-year overall survival of glioma patients. Overexpression of miR-1296 inhibited the proliferation, colony formation, migration and induced apoptosis of glioma cells. MiR-1296 was found to bind the 3’-untranslated region (UTR) of ABL proto-oncogene 2 (ABL2) and subsequently repressed both the mRNA and protein expression of ABL2. ABL2 was overexpressed in glioma tissues and inversely correlated with that of miR-1296. Ectopic expressed ABL2 could reverse the inhibitory effects of miR-1296 on glioma cell proliferation. Our results illustrated the novel tumor-suppressive function of miR-1296 in glioma via repressing ABL2, suggesting a potential application of miR-1296 in the treatment of glioma.
The effect of perineural dexamethasone on rebound pain after ropivacaine single-injection nerve block: a randomized controlled trial
Authors: Fang Jie , Shi Yuncen , Du Fang , Xue Zhanggang , Cang Jing , Miao Changhong , Zhang Xiaoguang
Published: February 2021

Background

Rebound pain after a single-shot nerve block challenges the real benefit of this technique. We aimed to investigate whether perineural dexamethasone addition decreased the incidence of rebound pain after a single-shot nerve block.

Methods

We randomly allocated 132 patients scheduled for open reduction internal fixation of an upper extremity closed fracture under single-shot peripheral nerve block and sedation into two groups. Patients in the dexamethasone group received nerve block with 0.375% ropivacaine and 8 mg dexamethasone, while those in the control group received ropivacaine only. Sixty-three patients in the dexamethasone group and 60 patients in the control group were analyzed for the incidence of rebound pain 48 h after block administration, which was the primary outcome. The secondary outcomes included the highest self-reported numeric rating scale (NRS) pain score, and NRS at 8, 12, 24, and 48 h after the block, sufentanil consumption, sleep quality on the night of surgery, patient satisfaction with the pain therapy, blood glucose at 6 h after the block, pain and paresthesia at 30 days after surgery.

Results

The incidence of rebound pain was significantly lower in the dexamethasone group (7 [11.1%] of 63 patients) than in the control group (28 [48.8%] of 60 patients [RR = 0.238, 95% CI (0.113–0.504), p = 0.001]. Dexamethasone decreased opioid consumption in 24 h after surgery (p < 0.001) and improved the sleep quality score on the night of surgery (p = 0.01) and satisfaction with pain therapy (p = 0.001). Multivariate logistic regression analysis showed that only group allocation was associated with the occurrence of rebound pain [OR = 0.062, 95% CI (0.015–0.256)]. Patients in the dexamethasone group reported later onset pain (19.7 ± 6.6 h vs 14.7 ± 4.8 h since block administration, mean ± SD, p < 0.001) and lower peak NRS scores [5 (3, 6) vs 8 (5, 9), median (IQR), p < 0.001] than those in the control group.

Conclusions

The perineural administration of 8 mg dexamethasone reduces rebound pain after a single-shot nerve block in patients receiving ORIF for an upper limb fracture.

Trial registration

This study was retrospectively registered in the Chinese Clinical Trial Registry (ChiCTR-IPR-17011365) on May 11th, 2017.