bluuebunny/crossref_metadata_2025 huggingface dataset:
Concircular vector fields for Kantowski–Sachs and Bianchi type-III spacetimes
Authors: Khan Suhail , Mahmood Amjad , Ali Ahmad T.
Published: April 2018

This paper intends to obtain concircular vector fields (CVFs) of Kantowski–Sachs and Bianch type-III spacetimes. For this purpose, ten conformal Killing equations and their general solution in the form of conformal Killing vector fields (CKVFs) are derived along with their conformal factors. The obtained conformal Killing vector fields are then placed in Hessian equations to obtain the final form of concircular vector fields. The existence of concircular symmetry imposes restrictions on the metric functions. The conditions imposing restrictions on these metric functions are obtained as a set of integrability conditions. It is shown that Kantowski–Sachs and Bianchi type-III spacetimes admit four-, six-, or fifteen-dimensional concircular vector fields. It is established that for Einstein spaces, every conformal Killing vector field is a concircular vector field. Moreover, it is explored that every concircular vector field obtained here is also a conformal Ricci collineation.
Degrees of freedom and problems in f(T) gravity
Authors: Ong Yen Chin
Published: April 2018

Torsion-based modified theories of gravity, such as [Formula: see text] gravity, are arguably one of the very few “true” modified gravities based on well-defined geometric structures. However, the original formulation explicitly works in a specific choice of frame, which has led to considerable amount of confusion in the literature about these theories breaking local Lorentz invariance. Pathological properties such as superluminal propagation and the lack of well-posedness of Cauchy problem were found to plague [Formula: see text] gravity. Recent effort to “covariantize” [Formula: see text] gravity has, however, renewed interests in this subject. In this proceeding paper, we review and discuss issues concerning the actual number of degrees of freedom in [Formula: see text] gravity, and how this might relate to the aforementioned pathologies.
One-Step Hydrothermal Synthesis of Bi2S3-TiO2-RGO Composites with Enhanced Visible Light Photocatalytic Activities
Authors: Li Yanan , Liu Zhongmin , Li Yaru , Wu Yongchuan , Chen Jitao , Liu Yanjun , Na Ping
Published: April 2018

The Bi2S3-TiO2-RGO composites were synthesized by a facile one-step hydrothermal method and applied for the photocatalytic degradation of Rhodamine B (Rh B) under the visible light. The Bi2S3-TiO2-RGO composites were characterized by transmission electron microscopy, X-ray diffraction, Raman and Fourier transform infrared spectrometer. The results indicated that the Bi2S3-TiO2-RGO composites were successfully prepared, and Ti-O-C and S-C bonds were existing among Bi2S3, TiO2 as well as RGO. Furthermore, the photocatalytic ability of Bi2S3-TiO2-RGO composites was excellent under visible light due to its responding to the whole visible light region, low recombination rate of photogenerated electron–hole pairs and relatively negative conduction band. Rh B photocatalytic degradation rate was 99.5% after 50[Formula: see text]min and still could reach 98.4% after five cycles. Finally, a formation mechanism as well as a photocatalytic mechanism of Bi2S3-TiO2-RGO composites were proposed based on the experimental results.
Topological 4-manifolds with right-angled Artin fundamental groups
Authors: Hambleton Ian , Hildum Alyson
Published: April 2018

We classify closed, spin[Formula: see text], topological [Formula: see text]-manifolds with fundamental group [Formula: see text] of cohomological dimension [Formula: see text] (up to [Formula: see text]-cobordism), after stabilization by connected sum with at most [Formula: see text] copies of [Formula: see text]. In general, we must also assume that [Formula: see text] satisfies certain [Formula: see text]-theory and assembly map conditions. Examples for which these conditions hold include the torsion-free fundamental groups of [Formula: see text]-manifolds and all right-angled Artin groupswhose defining graphs have no [Formula: see text]-cliques.
Degradation of multiphoton signal and resolution when focusing through a planar interface with index mismatch: Analytical approximation and numerical investigation
Authors: Qiu Ping , He Chen
Published: April 2018

Multiphoton microscopy (MPM) is an invaluable tool for visualizing subcellular structures in biomedical and life sciences. High-numerical-aperture (NA) immersion objective lenses are used to deliver excitation light to focus inside the biological tissue. The refractive index of tissue is commonly different from that of the immersion medium, which introduces spherical aberration, leading to signal and resolution degradation as imaging depth increases. However, the explicit dependence of this index mismatch-induced aberration on the involved physical parameters is not clear, especially its dependence on index mismatch. Here, from the vectorial equations for focusing through a planar interface between materials of mismatched refractive indices, we derive an approximate analytical expression for the spherical aberration. The analytical expression explicitly reveals the dependence of spherical aberration on index mismatch, imaging depth and excitation wavelength, from which we can expect the following qualitative behaviors: (1) Multiphoton signal and resolution degradation is less for longer excitation wavelength, (2) a longer wavelength tolerates a higher index mismatch, (3) a longer wavelength tolerates a larger imaging depth and (4) both signal and resolution degradations show the same dependence on imaging depth, regardless of NA or immersion on the condition that the integration angle is the same. Detailed numerical simulation results agree quite well with the above expectations based on the analytical approximation. These theoretical results suggest the use of long excitation wavelength to better suppress index mismatch-induced signal and resolution degradation in deep-tissue MPM.
Convergence of RK-iterative process for generalized nonexpansive mappings in CAT(0) spaces
Authors: Ritika  , Khan Safeer Hussain
Published: April 2018

In this paper, we introduce a new four-step iterative process and name it as RK-iterative process and prove some [Formula: see text]-convergence and strong convergence results using this process for generalized nonexpansive mappings in CAT(0) spaces. Our results generalize the corresponding results of many authors in different directions.
Modelling of the Current Density Distributions during Cortical Electric Stimulation for Neuropathic Pain Treatment
Authors: Fiocchi S. , Chiaramello E. , Ravazzani P. , Parazzini M.
Published: April 2018

In the last two decades, motor cortex stimulation has been recognized as a valuable alternative to pharmacological therapy for the treatment of neuropathic pain. Although this technique started to be used in clinical studies, the debate about the optimal settings that enhance its effectiveness without inducing tissue damage is still open. To this purpose, computational approaches applied to realistic human models aimed to assess the current density distribution within the cortex can be a powerful tool to provide a basic understanding of that technique and could help the design of clinical experimental protocols. This study aims to evaluate, by computational techniques, the current density distributions induced in the brain by a realistic electrode array for cortical stimulation. The simulation outcomes, summarized by specific metrics quantifying the efficacy of the stimulation (i.e., the effective volume and the effective depth of penetration) over two cortical targets, were evaluated by varying the interelectrode distance, the stimulus characteristics (amplitude and frequency), and the anatomical human model. The results suggest that all these parameters somehow affect the current density distributions and have to be therefore taken into account during the planning of effective electrical cortical stimulation strategies. In particular, our calculations show that (1) the most effective interelectrode distance equals 2 cm; (2) increasing voltage amplitudes increases the effective volume; (3) increasing frequencies allow enlarging the effective volume; and (4) the effective depth of penetration is strictly linked to both the anatomy of the subject and the electrode placement.
Discovering Associations of Adverse Events with Pharmacotherapy in Patients with Non-Small Cell Lung Cancer Using Modified Apriori Algorithm
Authors: Chen Wei , Yang Jun , Wang Hui-Ling , Shi Ya-Fei , Tang Hao , Li Guo-Hui
Published: April 2018

Aim. To explore the associations between adverse events and pharmacotherapy in patients with non-small cell lung cancer. Methods. 16,527 patients with non-small cell lung cancer admitted to the Cancer Hospital, Chinese Academy of Medical Sciences, between January 1, 2010, and December 31, 2016, were included in the study. Their medication and laboratory examinations data were extracted from the medical records. Common Terminology Criteria for Adverse Events Version 4.03 were utilized for adverse events reporting. A new association algorithm was developed based on Apriori algorithm and used to investigate the associations between drugs and adverse events. In addition, a statistical comparison was conducted to compare the modified Apriori algorithm with the conventional Apriori algorithm. Results. Different types and levels of adverse events were identified from the abnormal laboratory findings. The three most common adverse events were hypocalcemia, elevated creatine phosphokinase, and hypertriglyceridemia. In addition, using the modified Apriori algorithm, 380 association rules were found between adverse events and chemotherapy. Moreover, the statistical comparison of the two methods demonstrated that the modified Apriori algorithm was more advantageous in analyzing the correlation between drugs and adverse events than the conventional Apriori algorithm. Conclusions. The modified Apriori algorithm can be used to more efficiently associate pharmacotherapy with adverse events. Based on the modified Apriori algorithm, meaningful association rules between drugs and adverse events were found, demonstrating a promising way to reveal the risk factors of adverse events during cancer treatment.
Autoimmune Inner Ear Disease: Immune Biomarkers, Audiovestibular Aspects, and Therapeutic Modalities of Cogan’s Syndrome
Authors: Shamriz Oded , Tal Yuval , Gross Menachem
Published: April 2018

Cogan’s syndrome (CS) is a rare autoimmune disorder characterized by audiovestibular dysfunction and ocular inflammation. Currently, there is no specific serum autoantibody used in the diagnostic workup of CS. Treatment is based on immunosuppressive agents, mainly corticosteroids as first-line choice. Recently, novel therapeutic modalities in CS have emerged. These include tumor necrosis factor-α inhibitors and other biologicals. Despite medical treatment, hearing loss may progress to irreversible bilateral profound SNHL in approximately half of CS patients resulting in candidacy for cochlear implantation (CI). Due to the inflammatory nature of the disease that is causing endosteal reaction with partial obliteration or complete neoossification of the intracochlear ducts, early CI is recommended. CI provides excellent and stable hearing rehabilitation with high score of word and sentence recognition. In this review, we will discuss different aspects of CS including clinical presentation, diagnosis, treatment, and future directives.
Tiaolipiwei Acupuncture Reduces Albuminuria by Alleviating Podocyte Lesions in a Rat Model of Diabetic Nephropathy
Authors: Zhang Zhilong , Li Xinju , Liu Liang , Sun Jiya , Wang Xu , Zhao Zhiheng , Yang Yuanqing
Published: April 2018

Background. Diabetic nephropathy is a common and serious complication of diabetes and a major cause of end‐stage renal disease. Tiaolipiwei acupuncture is a safe treatment approach that may be effective for lowering albuminuria in diabetic nephropathy. Yet, the exact mechanisms of this therapeutic effect are unclear. Methods. A rodent model of type 2 diabetic nephropathy (T2DN) was induced by a high‐fat diet combined with low‐dose streptozotocin. T2DN rats were treated with Tiaolipiwei acupuncture (ACU) for 4, 8, or 12 weeks. At the end of treatment, urinary and blood samples were collected for analysis. Transmission electron microscopy was used to observe morphological changes, and protein expression levels of nephrin, CD2AP, podocalyxin, and desmin were quantified in renal tissue. Results. Compared to the T2DN groups, the T2DN + ACU groups showed significant improvements in 24‐hour urinary protein, serum urea, cholesterol, and triglycerides at all time points. ACU treatment also improved the density of slit diaphragms. Simultaneously, ACU promoted the renal expression of nephrin, CD2AP, and podocalyxin and decreased the expression of desmin. Conclusion. Our study suggests that Tiaolipiwei acupuncture ameliorates podocyte lesions to reduce albuminuria and prevent the progression of T2DN in a rat model.
A Dynamic Hidden Forwarding Path Planning Method Based on Improved Q-Learning in SDN Environments
Authors: Chen Yun , Lv Kun , Hu Changzhen
Published: April 2018

Currently, many methods are available to improve the target network’s security. The vast majority of them cannot obtain an optimal attack path and interdict it dynamically and conveniently. Almost all defense strategies aim to repair known vulnerabilities or limit services in target network to improve security of network. These methods cannot response to the attacks in real-time because sometimes they need to wait for manufacturers releasing corresponding countermeasures to repair vulnerabilities. In this paper, we propose an improved Q-learning algorithm to plan an optimal attack path directly and automatically. Based on this path, we use software-defined network (SDN) to adjust routing paths and create hidden forwarding paths dynamically to filter vicious attack requests. Compared to other machine learning algorithms, Q-learning only needs to input the target state to its agents, which can avoid early complex training process. We improve Q-learning algorithm in two aspects. First, a reward function based on the weights of hosts and attack success rates of vulnerabilities is proposed, which can adapt to different network topologies precisely. Second, we remove the actions and merge them into every state that reduces complexity from O(N3) to O(N2). In experiments, after deploying hidden forwarding paths, the security of target network is boosted significantly without having to repair network vulnerabilities immediately.
Constructing Temporally Extended Actions through Incremental Community Detection
Authors: Xu Xiao , Yang Mei , Li Ge
Published: April 2018

Hierarchical reinforcement learning works on temporally extended actions or skills to facilitate learning. How to automatically form such abstraction is challenging, and many efforts tackle this issue in the options framework. While various approaches exist to construct options from different perspectives, few of them concentrate on options’ adaptability during learning. This paper presents an algorithm to create options and enhance their quality online. Both aspects operate on detected communities of the learning environment’s state transition graph. We first construct options from initial samples as the basis of online learning. Then a rule-based community revision algorithm is proposed to update graph partitions, based on which existing options can be continuously tuned. Experimental results in two problems indicate that options from initial samples may perform poorly in more complex environments, and our presented strategy can effectively improve options and get better results compared with flat reinforcement learning.
Consumption of a High-Fat Diet Alters Perineuronal Nets in the Prefrontal Cortex
Authors: Dingess P. M. , Harkness J. H. , Slaker M. , Zhang Z. , Wulff S. S. , Sorg B. A. , Brown T. E.
Published: April 2018

A key factor in the development of obesity is the overconsumption of fatty foods, which, in addition to facilitating weight gain, alters neuronal structures within brain reward circuitry. Our previous work demonstrates that sustained consumption of a high-fat diet (HFD) attenuates spine density in the prefrontal cortex (PFC). Whether HFD promotes structural adaptation among inhibitory cells of the PFC is presently unknown. One structure of interest is the perineuronal net (PNN), a specialized extracellular matrix surrounding, primarily, parvalbumin-containing GABAergic interneurons. PNNs contribute to synaptic stabilization, protect against oxidative stress, regulate the ionic microenvironment within cells, and modulate regional excitatory output. To examine diet-induced changes in PNNs, we maintained rats on one of three dietary conditions for 21 days: ad libitum chow, ad libitum 60% high fat (HF-AL), or limited-access calorically matched high fat (HF-CM), which produced no significant change in weight gain or adiposity with respect to chow controls. The PNN “number” and intensity were then quantified in the prelimbic (PL-PFC), infralimbic (IL-PFC), and ventral orbitofrontal cortex (OFC) using Wisteria floribunda agglutinin (WFA). Our results demonstrated that fat exposure, independent of weight gain, induced a robust decrease in the PNN intensity in the PL-PFC and OFC and a decrease in the PNN number in the OFC.
Which Benefits and Harms of Using Fenugreek as a Galactogogue Need to Be Discussed during Clinical Consultations? A Delphi Study among Breastfeeding Women, Gynecologists, Pediatricians, Family Physicians, Lactation Consultants, and Pharmacists
Authors: Shawahna Ramzi , Qiblawi Sara , Ghanayem Haifa
Published: April 2018

Background. Breastfeeding women with hypogalactia are commonly recommended to use fenugreek as a galactogogue. This study aimed to achieve formal consensus among breastfeeding women and healthcare providers on which potential harms and benefits of using fenugreek need to be communicated and discussed during clinical consultations. Methods. A two‐iterative round Delphi technique was used in two separate panels of breastfeeding women (n = 65) and healthcare providers (n = 56) to achieve formal consensus on a list of 24 and 16 items related to potential harms and benefits of fenugreek. Results. About 70% of the healthcare providers recommended quite often herbal remedies for breastfeeding women and about 68% of the women had been recommended to use herbal remedies many times by their healthcare providers. Consensus was achieved on 21 potential harms and 14 potential benefits of using fenugreek to enhance human milk supply that need to be discussed with breastfeeding women during consultations. Conclusion. Probably, potential harms and benefits of recommending fenugreek as herbal galactogogue for breastfeeding women seeking recommendations to increase their human milk supply need to be discussed during clinical consultations. Further observational studies are needed to assess what is being discussed in daily consultations when herbal remedies are recommended.
Unsupervised versus Supervised Identification of Prognostic Factors in Patients with Localized Retroperitoneal Sarcoma: A Data Clustering and Mahalanobis Distance Approach
Authors: De Sanctis Rita , Viganò Alessandro , Giuliani Alessandro , Gronchi Alessandro , De Paoli Antonino , Navarria Pierina , Quagliuolo Vittorio , Santoro Armando , Colosimo Alfredo
Published: April 2018

The aim of this report is to unveil specific prognostic factors for retroperitoneal sarcoma (RPS) patients by univariate and multivariate statistical techniques. A phase I-II study on localized RPS treated with high-dose ifosfamide and radiotherapy followed by surgery (ISG-STS 0303 protocol) demonstrated that chemo/radiotherapy was safe and increased the 3-year relapse-free survival (RFS) with respect to historical controls. Of 70 patients, twenty-six developed local, 10 distant, and 5 combined relapse. Median disease-free interval (DFI) was 29.47 months. According to a discriminant function analysis, DFI, histology, relapse pattern, and the first treatment approach at relapse had a statistically significant prognostic impact. Based on scientific literature and clinical expertise, clinicopathological data were analyzed using both a supervised and an unsupervised classification method to predict the prognosis, with similar sample sizes (66 and 65, resp., in casewise approach and 70 in mean-substitution one). This is the first attempt to predict patients’ prognosis by means of multivariate statistics, and in this light, it looks noticable that (i) some clinical data have a well-defined prognostic value, (ii) the unsupervised model produced comparable results with respect to the supervised one, and (iii) the appropriate combination of both models appears fruitful and easily extensible to different clinical contexts.
Polyphenol Polymerization by an Alternative Oxidative Microbial Enzyme and Characterization of the Biological Activity of Oligomers
Authors: Di Gennaro Patrizia , Sabatini Valentina , Fallarini Silvia , Pagliarin Roberto , Sello Guido
Published: April 2018

The recombinant catalase-peroxidase HPI fromE. coliwas used as an alternative enzyme in polymerization reactions for the production of (−) epicatechin oligomers and their biological activity was characterized. The enzyme was prepared in two forms: a purified and an immobilized form. Both were tested for their activity in oxidative polymerization reactions, and their stability and reusability were assessed. The polymerization reactions were followed by SEC-HPLC analyses, and the substrate was completely converted into one or more polymerization products depending on the reactions conditions. Results showed that the utilized conditions allowed for the isolation of some oligomers of different molecular weight: the oligomers containing 6 and 7 units of epicatechin substrate are the heaviest ones. Epicatechin was also used in reactions catalyzed by HRP in the same reaction conditions for comparison. In addition, one selected oligomer obtained by HPI enzyme catalysis was shown to act asin vitroinhibitor of tumor cell growth, like one oligomer deriving from epicatechin by HRP catalysis. These data confirm that epicatechin oligomeric form is more effective than its monomer in biological activity and suggest the use of HPI as an alternative enzyme in reactions for the production of epicatechin oligomers.
Demonstration of Millimeter Wave 5G Setup Employing High-Gain Vivaldi Array
Authors: Sethi Waleed Tariq , Ashraf Muhammad Ahmed , Ragheb Amr , Alasaad Amr , Alshebeili Saleh A.
Published: April 2018

We present a 4 × 4 slot-coupled Vivaldi antenna (SCVA) array unit cell, which offers wide bandwidth and high gain (~23 dBi) at the millimeter wave (mmW) frequencies of 28 GHz and 38 GHz. A single SCVA element is first presented, which has a bandwidth of 25–40 GHz with an average gain of ~13 dBi at the frequencies of interest. This antenna element is then used to design a 1 × 4 linear SCVA array matched to a 50 Ω impedance via a modified Wilkinson power divider (WPD). Next, the 1 × 4 linear array is used to construct a 4 × 4 antenna array unit cell. The proposed 4 × 4 antenna array unit cell is fabricated, and the characteristics of its elements (i.e., the single SCVA, 1 × 4 linear array, and WPD) are thoroughly investigated. Further, the 4 × 4 array is tested for signal reception of various digital modulation formats at lab environment using high-speed digital signal oscilloscope. In particular, a 2.5 Gbps data rate is successfully transmitted achieving receiver sensitivity of −50 dBm at 2 × 10−3 bit error rate (BER) for 32 quadrature amplitude modulation (QAM) with a system baud rate of 500 MHz. The wide bandwidth and high gain along with the excellent performance of the proposed 4 × 4 antenna array unit cell makes it an excellent candidate for future 5G wireless communication applications.
Multiple Myeloma of the Central Nervous System: 13 Cases and Review of the Literature
Authors: Varga Gergely , Mikala Gábor , Gopcsa László , Csukly Zoltán , Kollai Sarolta , Balázs György , Botond Tímár , Wohner Nikolett , Horváth Laura , Szombath Gergely , Farkas Péter , Masszi Tamás
Published: April 2018

Central nervous system involvement is a rare complication of multiple myeloma with extremely poor prognosis as it usually fails to respond to therapy. We present 13 cases diagnosed at two centers in Budapest and review the current literature. The majority of our cases presented with high-risk features initially; two had plasma cell leukemia. Repeated genetic tests showed clonal evolution in 3 cases. Treatments varied according to the era, and efficacy was poor as generally reported in the literature. Only one patient is currently alive, with 3-month follow-up, and the patient responded to daratumumab-based treatment. Recent case reports show promising effectivity of pomalidomide and marizomib.
The Design and Implementation of the XWCETT Routing Algorithm in Cognitive Radio Based Wireless Mesh Networks
Authors: Kola L. M. , Velempini M.
Published: April 2018

The Wireless Mesh Networks (WMNs) technology has recently emerged as a promising high‐speed wireless technology, which provides the last mile broadband Internet access and delivers integrated wireless communication solutions. Integrating the traditional wireless with new wireless technologies such as cognitive radio (CR) technology creates a platform for high‐speed broadband communication. In a multihop ad hoc cognitive radio network (CRN) environment, the performance of the network is degraded by the routing protocols, which are adapted from the traditional wireless networks. In an endeavor to optimize the performance of the CRNs, existing routing protocols can be adapted and optimized. Secondly, new dynamic routing protocols can be designed to meet the requirements of CRNs. This paper investigates the existing routing protocols in WMNs and proposes a new routing protocol called extended Weighted Cumulative Expected Transmission Time (xWCETT). The xWCETT routing protocol was evaluated through network simulations using the NS 2. Its performance was evaluated with respect to the end‐to‐end average latency, the throughput, jitter, packet delivery ratio, and the normalized routing load. The comparative evaluation results show that the xWCETT achieves superior results in terms of average throughput, latency, and the normalized routing load.
Comparison on the Efficacy between Partially Covered Self-Expandable Metal Stent with Funnel-Shaped Enlarged Head versus Uncovered Self-Expandable Metal Stent for Palliation of Gastric Outlet Obstruction
Authors: Choe Jung Wan , Hyun Jong Jin , Lee Dong-won , Suh Sang Jun , Kim Seung Young , Jung Sung Woo , Jung Young Kul , Koo Ja Seol , Yim Hyung Joon , Lee Sang Woo
Published: April 2018

Background. Shape modification has been one of the methods adopted to improve stent patency but has not always translated into positive outcome. The aim of this study was to compare the efficacy of shape-modified partially covered self-expandable metal stent (SEMS) that has enlarged head versus uncovered SEMS for palliation of gastric outlet obstruction (GOO). Methods. A total of 48 patients underwent insertion of either enlarged-head SEMS (n=24) or uncovered SEMS (uSEMS) (n=24) for palliation of GOO from July 2009 to July 2016. Patients with inoperable or advanced malignancy were included. Technical feasibility and clinical outcomes were compared. Results. Technical success rate was 100% (24/24) and 95.8% (23/24) for enlarged-head SEMS group and uSEMS group, respectively. Clinical success rate was 87.5% (21/24) and 87.0% (20/23) for enlarged-head SEMS group and uSEMS group, respectively. The gastric outlet obstruction scoring system score significantly improved in both groups (p<0.001 for both). Mean survival was similar between the groups: enlarged-head SEMS group, 99.3 days (range, 19–358 days) versus uSEMS group, 82.1 days (range, 11–231 days) (p=0.418). The mean stent patency also showed no difference between the groups: enlarged-head SEMS group, 87.1 days (range, 8–358 days) versus uSEMS group, 60.4 days (range, 2–231 days) (p=0.204). With enlarged-head SEMS, distal migration did not occur, but proximal migration was observed in four cases. Conclusions. Distal migration was prevented by shaping the SEMS to have an enlarged head, but improvement in stent patency could not be observed.
Long Time from Diagnosis to Surgery May Increase Postoperative Complication Rates in Elective CD Intestinal Resections: An Observational Study
Authors: Kotze Paulo Gustavo , Magro Daniela Oliveira , Martinez Carlos Augusto Real , Spinelli Antonino , Yamamoto Takayuki , Warusavitarne Janindra , Coy Claudio Saddy Rodrigues
Published: April 2018

Background. There is lack of data analyzing short-term postoperative complications and time from diagnosis to surgery in Crohn’s disease (CD). Aim. To compare complication rates after elective abdominal operations in CD patients with different durations of disease. Methods. Retrospective observational study with CD patients who submitted to elective intestinal resections. Patients were allocated in 2 groups according to time to surgery (TS) in less or more than 5 years. Short-term postoperative complications were analyzed and compared between the 2 groups, and binary logistic regression analysis was performed to check for significant variables. Results. 123 patients were finally included, 77 with TS > 5 years (62.6%) and 46 with TS < 5 years (37.4%). Patients with TS > 5 years had higher rates of overall surgical complications (p=0.011), reoperations (p=0.003), surgical site infections (p=0.014), anastomotic dehiscence (p=0.021), abdominal abscesses (p=0.021), and overall medical complications (p=0.019). On logistic regression, the single significant variable was the confection of stomas (OR: 3.203; 95% CI: 1.011–10.151; p=0.048). Conclusions. Patients with longer time to surgery showed a significant increase in overall medical and surgical postoperative early complications after elective intestinal resections.
An In Vivo Study on Intoxicating Effects of Nerium oleander Water Based Extract on Multiorgans of Wistar Rat
Authors: Abbasi Muddasir Hassan , Fatima Sana , Khawar Muhammad Babar , Jahan Shah , Sheikh Nadeem
Published: April 2018

This study was aimed to find histological changes in the extrahepatic organs, hepatic iron deposition, and gene expression of some iron regulatory proteins in rats after sterile muscle abscess during the acute intoxication of Nerium oleander leaves decoction. 10 ml/kg of the leaves extract was injected intramuscularly in Wistar rats (200–225 g, n=4). Control animals received saline injection of matched volume. Animals were anesthetized and sacrificed after 3, 6, 12, and 24 h after administration of decoction. Lungs, kidney, spleen, and liver were extracted and processed for histopathological examination while portion of liver tissue was proceeded for iron regulatory gene expression quantification. Sections of all studied organs were found with signs of cellular dysfunction with infiltration of variety of leucocytes. In the lungs section at 3 h time point mononuclear cell infiltrates were observed while in alveolar tissue at 24 h time point dilation and even collapse in some of the alveoli were evident. In kidney sections distortion of renal tubules and epithelial cells with shrinkage of glomeruli was noted at all studied time points. In the splenic section of 12 h time point, degeneration, depopulation, and shrinkage of white pulp have been noted. Distension of the red pulp along with activation of splenic follicles was evident after 24 h onset of APR. Significant changes in the expression of acute phase cytokine and iron regulatory genes were noted. IL-6 and Hepc gene expression were strongly upregulated up to 12 h whereby Tf gene expression showed an early upregulation at 3 h time point followed by downregulation on later points while Hjv gene expression showed an overall downregulation at all study time points compared to control. It is concluded that inherent toxins present in the N. oleander can induce acute phase response and cause severe histological changes in the organs and marked changes in the regulation of iron regulatory proteins thus cannot be practiced routinely.
Antihypertensive Effect of Ethanolic Extract from Acanthopanax sessiliflorus Fruits and Quality Control of Active Compounds
Authors: Jung In Ho , Kim Sung Eun , Lee Yeong-Geun , Kim Dae Hyun , Kim Haneul , Kim Geum-Soog , Baek Nam-In , Lee Dae Young
Published: April 2018

Acanthopanax sessiliflorus (Rupr. & Maxim.) Seem., which belongs to the Araliaceae family, mainly inhabits Korea, China, and Japan. Traditionally, Acanthopanax species have been used as treatment for several diseases such as diabetes, tumors, and rheumatoid arthritis. Especially, its fruits have many biological functions including antitumor, immunostimulating, antithrombosis, and antiplatelet activities. Recently, the extract of A. sessiliflorus fruit has been reported to have antithrombotic and antiplatelet activities related to the alleviation of hypertension. Therefore, we investigated the antihypertensive effect of ethanolic extract from A. sessiliflorus fruits (DHP1501) through in vivo, ex vivo, and in vitro studies. In this study, DHP1501 demonstrated free radical scavenging capacity, enhanced endothelial nitric oxide (NO) production, and inhibited angiotensin‐converting enzyme (ACE) activity in spontaneously hypertensive rats (SHRs), resulting in the improvement of vascular relaxation and decrease in blood pressure in the hypertensive animal model. These results suggest that A. sessiliflorus fruit extract may be a promising functional material for the prevention and treatment of hypertension. Furthermore, this study demonstrated the utility of MS‐based active compounds for the quality control of DHP1501.
T-S Fuzzy-Based Optimal Control for Minimally Invasive Robotic Surgery with Input Saturation
Authors: Wang Faguang , Wang Hongmei , Zhang Yong , Guo Xijin
Published: April 2018

A minimally invasive surgery robot is difficult to control when actuator saturation exists. In this paper, a Takagi-Sugeno fuzzy model-based controller is designed for a minimally invasive surgery robot with actuator saturation, which is difficult to control. The contractively invariant ellipsoid theorem is applied for the actuator saturation. The proposed scheme can be derived using the H-infinity control theorem and parallel distributed compensation. The result is rebuilt in the form of linear matrix inequalities for easier calculation by computer. Meanwhile, the uniformly ultimately bounded stable and the prescribed H-infinity control performance can be guaranteed. The proposed scheme is simulated in a Novint Falcon haptic device system.
Association between Neighborhood Conditions and Mental Disorders among Children in the US: Evidence from the National Survey of Children’s Health 2011/12
Authors: Dahal Sushma , Swahn Monica H. , Hayat Matthew J.
Published: April 2018

Background. This study examines the association between mental disorders and neighborhood conditions in a nationally representative sample of US children. Methods. Data from US children aged 6–17 years (N=95,677) were obtained from the 2011/12 National Survey of Children’s Health. Analysis examined neighborhood conditions and demographic and psychosocial characteristics including adverse childhood experiences (ACEs), parental mental health status, and the associations with any current diagnosed mental disorders (ACDMD). ACDMD was a composite variable derived from four childhood mental disorders examined. We computed descriptive statistics and logistic regression analyses. Results. Approximately 14% children had ACDMD. Of the neighborhood factors examined, nonsupportive neighborhood (AOR 1.37, 95% CI: 1.10, 1.71) was significantly associated with ACDMD in the multivariable models. Similarly, mother’s mental health (AOR 1.84, 95% CI: 1.39, 2.43) and ACEs (e.g., AOR for 5–9 ACEs 6.36, 95% CI: 4.67, 8.65) were also found to be strongly associated with mental disorders. Conclusion. Our findings show that parental poor mental health, living in a nonsupportive neighborhood, and ACEs were important risk factors for child mental disorders. While more research is needed, children who have had early trauma and who reside with parents and caretakers with poor mental health are in need of additional services and treatment.
Aberrant Peripheral Immune Function in a Good Syndrome Patient
Authors: Chen Xian , Zhang Jie-xin , Shang Wen-wen , Xie Wei-ping , Jin Shu-xian , Wang Fang
Published: April 2018

Good’s syndrome (GS) is often accompanied by recurrent respiratory infections and chronic diarrhea. The main purpose was to evaluate the peripheral immune status of a GS patient after thymoma resection. Twenty healthy volunteers were recruited as healthy controls (HCs). Flow cytometry was applied to determine the proportions of circuiting CD4+ T cells, CD8+ T cells, γδT cells, and regulatory T (Treg) cells in our GS patient. We also examined the proliferation capability of ex vivo CD4+ T cells and detected the levels of cytokines interferon- (IFN-) γ and interleukin-17A secreted by ex vivo immune cells from this GS patient. Compared with healthy control subjects, this GS patient had fewer B cells, an inverted ratio of CD4+/CD8+ cells, and more Treg cells in his peripheral blood. Additionally, the patient’s Vδ2 T cell levels were significantly decreased despite having a normal percentage of γδT cells. Ex vivo peripheral CD4+ T cells from the patient showed insufficient proliferation and division potential as well as excessive expression of PD-1. Moreover, IFN-γ was predominantly derived from CD8+ T cells in this GS patient, rather than from CD4+ T cells and γδT cells. This GS patient had impaired T and B cell immunological alternations and cytokine disruptions after thymectomy. Detailed research should focus on therapies that can adjust the immune status in such patients for a better outcome.
Cigarette Smoke‐Induced Acquired Dysfunction of Cystic Fibrosis Transmembrane Conductance Regulator in the Pathogenesis of Chronic Obstructive Pulmonary Disease
Authors: Shi Juan , Li Hui , Yuan Chao , Luo Meihui , Wei Jun , Liu Xiaoming
Published: April 2018

Chronic obstructive pulmonary disease (COPD) is a disease state characterized by airflow limitation that is not fully reversible. Cigarette smoke and oxidative stress are main etiological risks in COPD. Interestingly, recent studies suggest a considerable overlap between chronic bronchitis (CB) phenotypic COPD and cystic fibrosis (CF), a common fatal hereditary lung disease caused by genetic mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Phenotypically, CF and COPD are associated with an impaired mucociliary clearance and mucus hypersecretion, although they are two distinct entities of unrelated origin. Mechanistically, the cigarette smoke‐increased oxidative stress‐induced CFTR dysfunction is implicated in COPD. This underscores CFTR in understanding and improving therapies for COPD by altering CFTR function with antioxidant agents and CFTR modulators as a great promising strategy for COPD treatments. Indeed, treatments that restore CFTR function, including mucolytic therapy, antioxidant ROS scavenger, CFTR stimulator (roflumilast), and CFTR potentiator (ivacaftor), have been tested in COPD. This review article is aimed at summarizing the molecular, cellular, and clinical evidence of oxidative stress, particularly the cigarette smoke‐increased oxidative stress‐impaired CFTR function, as well as signaling pathways of CFTR involved in the pathogenesis of COPD, with a highlight on the therapeutic potential of targeting CFTR for COPD treatment.
Uniform Boundedness Principle for Nonlinear Operators on Cones of Functions
Authors: Peperko Aljoša
Published: April 2018

We prove a uniform boundedness principle for the Lipschitz seminorm of continuous, monotone, positively homogeneous, and subadditive mappings on suitable cones of functions. The result is applicable to several classes of classically nonlinear operators.
Cholangiocarcinoma in a Child with Progressive Abdominal Distension and Secondary Hypercalcemia
Authors: Monsereenusorn Chalinee , Satayasoontorn Kantang , Rujkijyanont Piya , Traivaree Chanchai
Published: April 2018

Cholangiocarcinoma is extremely rare in childhood and has been reported in association with other underlying diseases. The survival and prognosis are dismal especially in patients with unresectable or advanced stage cholangiocarcinoma. Overall survival in patients with metastatic cholangiocarcinoma could be increased by using combination chemotherapy with cisplatin and gemcitabine. A case of childhood cholangiocarcinoma was hereby reported.
Normothermic Ex Vivo Machine Perfusion for Liver Grafts Recovered from Donors after Circulatory Death: A Systematic Review and Meta-Analysis
Authors: Nostedt Jordan J. , Skubleny Daniel T. , Shapiro A. M. James , Campbell Sandra , Freed Darren H. , Bigam David L.
Published: April 2018

As a result of donation after circulatory death liver grafts’ poor tolerance to cold storage, there has been increasing research interest in normothermic machine perfusion. This study aims to systematically review the current literature comparing normothermic perfusion to cold storage in donation after circulatory death liver grafts and complete a meta-analysis of published large animal and human studies. A total of nine porcine studies comparing cold storage to normothermic machine perfusion for donation after circulatory death grafts were included for analysis. There was a significant reduction in AST (mean difference −2291 U/L, CI (−3019, −1563); P ≤ 0.00001) and ALT (mean difference −175 U/L, CI (−266, −85); P=0.0001), for normothermic perfusion relative to static cold storage, with moderate (I2 = 61%) and high (I2 = 96%) heterogeneity, respectively. Total bile production was also significantly higher (mean difference = 174 ml, CI (155, 193); P≤0.00001). Further research focusing on standardization, performance of this technology following periods of cold storage, economic implications, and clinical trial data focused on donation after circulatory death grafts will be helpful to advance this technology toward routine clinical utilization for these grafts.
Intelligent UAV Map Generation and Discrete Path Planning for Search and Rescue Operations
Authors: San Juan Víctor , Santos Matilde , Andújar José Manuel
Published: April 2018

Search and Rescue Operations (SAR) take place in any emergency situation where people are involved and their lives are at risk. These operations are nowadays carried out with the help of advanced technology, such as Unmanned Aerial Vehicles (UAVs). In this work, several methods are proposed to calculate the UAV discrete path planning. Previously, an intelligent characterization of the searching area is performed to estimate a potential risk/occupancy degree of the gridding map. This estimation is mainly based on fuzzy logic, considering different factors. Then, four methods are applied to calculate the path planning: an original proposal called attraction, fuzzy logic, ANFIS, and a PSO algorithm. All of them calculate the location of the waypoints to be followed by the UAVs to minimize the distance and the risk the people is exposed to. Then, these strategies are adapted to the possibility of having more than one UAV searching at the same time, and the swarm formation is discussed. Finally, these four solutions for path planning, including different number of UAVs, are tested in a real simulation scenario, and then the performance of each method is analyzed and compared with the others.
Impact of Simulated Knee Injuries on the Patellofemoral and Tibiofemoral Kinematics Investigated with an Electromagnetic Tracking Approach: A Cadaver Study
Authors: Rath Björn , Asseln Malte , Betsch Marcel , Prescher Andreas , Tingart Markus , Eschweiler Jörg
Published: April 2018

Purpose.The purpose of this study was to evaluate the approach of using an electromagnetic tracking (EMT) system for measuring the effects of stepwise, simulated knee injuries on patellofemoral (PF) and tibiofemoral (TF) kinematics.Methods.Three cadaver knees were placed in a motion rig. EMT sensors were mounted on the patella, the medial/lateral femoral epicondyles, the tibial condyle, and the tibial tuberosity (TT). After determining the motion of an intact knee, three injuries were simulated and the resulting bony motion was tracked.Results.Starting with the intact knee fully extended (0° flexion) and bending it to approximately 20°, the patella shifted slightly in the medial direction. Then, while bending the knee to the flexed position (90° flexion), the patella shifted progressively more laterally. After transecting the anterior cruciate ligament (ACL), the base of the medial menisci (MM) at the pars intermedia, and the medial collateral ligament (MCL), individual changes were observed. For example, the medial femoral epicondyle displayed a medial lift-off in all knees.Conclusion.We demonstrated that our EMT approach is an acceptable method to accurately measure PF joint motion. This method could also enable visualization and in-depth analysis of in vivo patellar function in total knee arthroplasty, if it is established for routine clinical use.
Genetic Code Expansion: A Powerful Tool for Understanding the Physiological Consequences of Oxidative Stress Protein Modifications
Authors: Porter Joseph J. , Mehl Ryan A.
Published: April 2018

Posttranslational modifications resulting from oxidation of proteins (Ox‐PTMs) are present intracellularly under conditions of oxidative stress as well as basal conditions. In the past, these modifications were thought to be generic protein damage, but it has become increasingly clear that Ox‐PTMs can have specific physiological effects. It is an arduous task to distinguish between the two cases, as multiple Ox‐PTMs occur simultaneously on the same protein, convoluting analysis. Genetic code expansion (GCE) has emerged as a powerful tool to overcome this challenge as it allows for the site‐specific incorporation of an Ox‐PTM into translated protein. The resulting homogeneously modified protein products can then be rigorously characterized for the effects of individual Ox‐PTMs. We outline the strengths and weaknesses of GCE as they relate to the field of oxidative stress and Ox‐PTMs. An overview of the Ox‐PTMs that have been genetically encoded and applications of GCE to the study of Ox‐PTMs, including antibody validation and therapeutic development, is described.
Event‐Based Time Varying Formation Control for Multiple Quadrotor UAVs with Markovian Switching Topologies
Authors: Zhou Zhen , Wang Hongbin , Hu Zhongquan
Published: April 2018

Time varying formation control problem for a group of quadrotor unmanned aerial vehicles (UAVs) under Markovian switching topologies is investigated through a modified dynamic event‐triggered control protocol. The formation shape is specified by a time varying vector, which prescribes the relative positions and bearings among the whole agents. Instead of the general stochastic topology, the graph is governed by a set of Markov chains to the edges, which can recover the traditional Markovian switching topologies in line with the practical communication network. The stability proof for the state space origin of the overall closed‐loop system is derived from the singular perturbation method and Lyapunov stability theory. An event‐triggered formation control protocol in terms of a dynamically varying threshold parameter is delicately carried out, while acquiring satisfactory resource efficiency, and Zeno behavior of triggering time sequences is excluded. Finally, simulations on six quadrotor UAVs are given to verify the effectiveness of the theoretical results.