bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural stability, hardness, fracture toughness and melting points of Ta1-xHfxC and Ta1-xZrxC ceramics from first-principles
Authors: Zhang Shuoxin , Liu Shiyu , Yan Dali , Yu Qian , Ren Haitao , Yu Bin , Li Dejun
Published: March 2020

We systematic investigated the influence of substitution of Hf and Zr atoms for Ta atoms in TaC using first-principles supercell (SC) method and virtual crystal approximation (VCA) methods, including the impurity formation energy, lattice constant, volume, elastic constants, elastic moduli, melting points, fracture toughness and density of states of the Ta 1-x Hfx C and Ta1-x Zrx C ceramics in the whole range of content 0≤ x ≤1. Our calculated results show that the stability of Ta 1-x Hf x C and Ta 1-x Zrx C increases with the increase of Hf and Zr content, and Ta1-x Zrx C is more stable than Ta1-x Hfx C at the same content of Hf and Zr. The lattice constants and volumes dilate with the increase of Hf and Zr content. Furthermore, Ta1-x Hfx C and Ta1-x Zrx C carbides are mechanically stable and brittle. The bulk modulus of Ta1-x Hfx C and Ta1-x Zrx C decreases with the increasing content of Hf and Zr. Moreover, the hardness, fracture toughness, and melting point of Ta1-x Hf x C and Ta1-x Zrx C solid solutions have the peak. In particular, Ta0.8Hf0.2C has the highest hardness, largest fracture toughness and highest melting temperature.
Diagnostic and prognostic significance of dysregulated expression of circular RNAs in osteosarcoma
Authors: Zhang Chenghao , He Jieyu , Qi Lin , Duan Zhixi , Wan Lu , Wang Wanchun , Tu Chao , Li Zhihong
Published: March 2020

Background Circular RNAs (circRNAs) have emerged as pivotal regulators in osteosarcoma tumorigenesis and progression, but their prognostic and diagnostic significance remain unclear. Herein, we aimed to perform an updated meta-analysis to explore the clinical, diagnostic and prognostic values of circRNAs in osteosarcoma. Methods Several databases, including PubMed, Web of Science, EMBASE, Scopus and Cochrane Library, were systematically searched up to Mar 10, 2020. Eligible studies regarding the relationship between circRNAs levels and clinicopathological, diagnostic and prognostic values in osteosarcoma patients were included in this study. Pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to measure clinical characteristics, while hazard ratios (HRs) with 95% CIs were adopted to assess overall survival (OS) and disease-free survival (DFS). Results Overall, 26 relevant studies involving 1,652 patients with osteosarcoma were enrolled, with eighteen studies on clinicopathological parameters, ten on diagnosis and eighteen on prognosis. For clinical parameters, overexpression of oncogenic circRNAs was intimately correlated with larger tumor size (P <0.00001), advanced Enneking stage (P <0.00001), poor differentiation (P =0.0001), and distant metastasis (DM) (P <0.00001). In contrast, the downregulated circRNAs showed negative correlation with Enneking stage (P=0.002) and DM (P<0.0001). For the diagnostic values, the summary area under the curve (AUC) of circRNA for the discriminative efficacy between osteosarcoma patients and non-cancer counterparts was estimated to be 0.86 (95% CI: 0.83-0.89), with a weighted sensitivity of 0.80 (95% CI: 0.74-0.84), specificity of 0.80 (95%: 0.75-0.84), and diagnostic odds ratio (DOR) of 15.48 (10.85-22.10), respectively. For the prognostic significance, oncogenic circRNAs had poor OS (HR=1.92, 95% CI: 1.68-2.19) and DFS (HR=2.65, 95% CI: 2.02-3.49), while elevated expression of tumor-suppressor circRNAs were closely related to longer OS (HR=0.44, 95% CI: 0.28-0.69). Conclusions Taken together, our study showed that aberrantly expressed circRNA signatures could serve as potential predictive indicators in diagnosis and prognosis in patients with osteosarcoma.
Study on Functional Monoclonal Antibodies of Anti-Human Uterine Sarcoma Stem Cell-Like Cells
Authors: Cai Jingting , Gao Jiuping , Zhang Beilei , Tang Dihong , Gao Ting , Lin Qiuhui , Tang Jun , Chu Chaonan , Yang Ting , Wang Jing , Wang Jing
Published: March 2020

Background: To establish a functional monoclonal antibody library using Human Uterine Sarcoma Stem Cell-Like Cells (HUSSLCs) to screen and identify functional monoclonal antibodies that can recognize and inhibit HUSSLCs. Methods: B lymphocytes in proliferative state were prepared by using the second generation CD133+spheroid cells of SK-UT-1 cell line, i.e. HUSSLCs, as antigens; Spheroid formation, agar colony formation, wound healing, flow cytometry, and Western blotting were adopted to detect the effect of monoclonal antibodies with varied dilution ratios on HUSSLCs spheroid formation, agar colony formation, cell migration, CD133 expression, and expression of CD44, ABCG2, Bmi1, Nanog, Oct4 and ALDH1. Results: Myeloma cells of SP2/0 cell line can achieve 85% degrees of fusion and results of 1-2F monoclonal cell supernatants with different dilution ratios reduced HUSSLCs spheroid formation rate, agar colony formation rate, cell migration rate, CD133 positive cell expression and protein expression levels of CD44, ABCG2, Bmi1, Nanog, Oct4, and ALDH1 in concentration-dependent manner (P <0.05). Conclusion: The antibody valence produced by HUSSLCs-immunized mice reached the requirement for preparation of monoclonal antibody. Anti-HUSSLCs monoclonal antibodies feature functions of inhibiting the self-renewal, unrestricted proliferation, migration, invasion and multidrug resistance of HUSSLCs and functions characterized by tumor stem cells. Key words: uterine leiomyosarcoma; tumor stem cell; monoclonal antibody; self-renewal ability; infinite multiplication; drug resistance
Knockdown of lncRNA LINC01234 suppresses the tumorigenesis of liver cancer via sponging miR-513a-5p
Authors: Xu Wen , Li Kesang , Song Changfeng , Wang Xiaotong , Li Yueqi , Bai Xue , Liang Xin , Deng Wanli , Wang Junqing , Liu Jianwen
Published: March 2020

Background Liver cancer is a frequent malignancy with poor prognosis. It has been reported that many lncRNAs could regulate the progression of liver cancer. To identify potential therapeutic targets for liver cancer, we conducted bioinformatics analysis of lncRNAs in tumor tissues and adjacent normal tissues. Methods The differential expression of lncRNAs between liver cancer tissues and adjacent normal tissues were examined by bioinformatics analysis. Cell proliferation was tested by CCK-8. Cell apoptosis in liver cancer was detected by flow cytometry. Gene and protein expression in liver cancer cells were measured by q-PCR and Western-blot, respectively. Xenograft tumor model was established to verify the function of LNC01234 on liver cancer in vivo. Results LNC01234 was found to be notably upregulated in liver cancer tissues. In addition, knockdown of LNC01234 significantly inhibited the proliferation, invasion and induced the apoptosis of liver cancer cells. Meanwhile, miR-513a-5p was a downstream target of LNC01234 and USP4 was a direct target of miR-513a-5p. Moreover, downregulation of LNC01234 inhibited the tumorigenesis of liver cancer via inactivating TGF-β signaling. Conclusion Downregulation of LNC01234 could inhibit the progression of liver cancer, which may serve as a potential novel target for treatment of liver cancer.
Contemporary management of brain arteriovenous malformations in mainland China: a web-based nationwide questionnaire survey
Authors: Yu Chen , Meng Xiangyu , Ma Li , Zhao Yang , Gu Ye , Jin Hengwei , Gao Dezhi , Li Youxiang , Sun Shibin , Liu Ali , Zhao Yuanli , Chen Xiaolin , Wang Shuo
Published: March 2020

Background:In the benefit of the large population and rapid economic growth, the interventional techniques and equipment for brain arteriovenous malformations (bAVMs) in mainland China have been rapidly improved. Chinese neurosurgical cerebrovascular physicians have accumulated rich experience and made pioneering explorations. This study aims to summarize the experience and treatment progress of bAVMs in mainland China.Methods:We performed a web-based nationwide questionnaire survey among 67 tertiary neurosurgical institutions that had acknowledged treating bAVMs in the primary survey. Our questionnaire included clinical characteristics, radiological findings, intervention indications/contraindications, intervention timing, and intraoperative management of different treatment modalities. Results:A total of 63 participants from 49 (73.1%) tertiary neurosurgical institutions responded to our questionnaire. 42 (66.7%) were neurosurgeons, 13 (20.6%) were neurointerventionists, and 8 (12.7%) were radiosurgeons. Approximately 3500 to 4000 cases of bAVMs were treated annually in these 49 departments. All participants agreed that the conclusions of ARUBA are debatable. Flow-related aneurysms, deep venous drainage, and arteriovenous fistula were considered as common hemorrhagic risk factors. Unruptured SM IV-V bAVMs, giant bAVMs, pediatric bAVMs, elderly bAVMs, and eloquent bAVMs were not absolute contraindications to intervention. Maximum lesion occlusion and minimal functional impairment were the principles of intervention management. Most of the neurosurgeons and neurointerventionists recommended early intervention (<30 days) for ruptured bAVMs, and the radiosurgeons suggested intervention in the chronic phase or recovery phase (P<0.01), and preferably 3 months after bleeding. Multi-modality strategies were thought effective for complex bAVMs and more exploration of individualized intraoperative management was necessary.Conclusions:Intervention was acceptable for specific selected unruptured bAVMs in mainland China, especially in patients with hemorrhagic risk factors. The application of multidisciplinary cerebrovascular team and multicenter large-sample international registry study might be the next work for Chinese neurosurgical cerebrovascular physicians.
Obstacle avoidance and multitarget tracking of a super redundant modular manipulator based on Bezier curve and particle swarm optimization
Authors: Li Chen , Ma Ying , Zhang Yu , Liu Jinguo
Published: March 2020

A super redundant serpentine manipulator has slender structure and multiple degrees of freedom and can travel through narrow space and move in complex space. This manipulator is composed of many modules that can form different lengths of robot arms for different application sites. The increase in degrees of freedom causes the inverse kinematics of redundant manipulator to be typical and immensely increases the calculation load in the joint space. This paper presents a composite optimization method of path planning for obstacle avoidance and discrete trajectory tracking of a super redundant manipulator. In this composite optimization, path planning is established on a Bezier curve, particle swarm optimization is adopted to adjust the control points of the Bezier curve with the kinematic constraints of manipulator, and a feasible obstacle avoidance path is obtained along with a discrete trajectory tracking using a follow-the-leader strategy. The relative distance between each two discrete path points is limited to reduce the fitting error of the connecting rigid links to the smooth curve. Simulation results show that this composite optimization method can rapidly search for the appropriate trajectory to guide the manipulator in obtaining the target while achieving obstacle avoidance and meeting joint constraints. The proposed algorithm is suitable for 3D space obstacle avoidance and multitarget path tracking.
Finite Cell Method for functionally graded materials based on V-models and homogenized microstructures
Authors: Wassermann Benjamin , Korshunova Nina , Kollmannsberger Stefan , Rank Ernst , Elber Gershon
Published: March 2020

This paper proposes a computational methodology that allows a direct numerical simulation of heterogeneous/functionally graded materials based on V-reps/V-models and the Finite Cell Method (FCM). The FCM is an embedded domain approach that employs higher-order ﬁnite elements. The basic idea is to embed a complex geometric model into a ﬁctitious domain that is trivial to mesh. The complexity of the geometry is then recaptured by an adapted precise numerical integration scheme for the elements cut by the boundary. For this, only a robust point inclusion test is required, which can be provided by various Computer-Aided Design (CAD) models. V-rep is a geometric modeling framework that represents the entire volume based on tri-variate B-Splines. Consequently, not only a point inclusion test is provided – but also the possibility to represent and model the interior domain. This allows to apply functionally graded material based on the tri-variate basis functions. These material parameters can then be regained during the simulation with an adapted point inclusion test. The potential of the proposed method especially in the context of additive manufacturing is demonstrated by several numerical examples.
Transduction of inflammation from peripheral immune cells to the hippocampus induces neuronal hyperexcitability mediated by Caspase-1 activation
Authors: Shaker Tarek , Chattopadhyaya Bidisha , Amilhon Bénédicte , Cristo Graziella Di , Weil Alexander G.
Published: March 2020

Background Recent studies report infiltration of peripheral blood mononuclear cells (PBMCs) into the central nervous system (CNS) in epileptic disorders, suggestive of a potential contribution of PBMC extravasation to the generation of seizures. Nevertheless, the underlying mechanisms involved in PBMC infiltrates promoting neuronal predisposition to ictogenesis remain unclear. Therefore, we developed an in vitro model mimicking PBMC infiltration into the brain in order to investigate potential transduction of inflammatory signals from PBMCs to the CNS.MethodsTo establish our model, we first extracted PBMCs from rat spleen, then, we immunologically primed PBMCs with lipopolysaccharide (LPS), followed by immunological activation with Nigericin. Thereafter, we cultured PBMCs on top of organotypic cortico-hippocampal brain slice cultures (OCHSCs) derived from the same rat, and compared PBMC-OCHSC co-cultures to OCHSCs exposed to PBMCs in the culture media. Also, we targeted a potential molecular pathway underlying transduction of peripheral inflammation to OCHSCs by incubating OCHSCs with the Caspase-1 inhibitor VX-765 prior to co-culturing PBMCs with OCHSCs. After 24 hours, we immunohistochemically analyzed inflammation markers in the cortex and the hippocampus. In addition, we performed whole-cell patch-clamp recordings in cortical layer II/III and hippocampal CA1 pyramidal neurons.ResultsIn the cortex, co-culturing immunoreactive PBMCs treated with LPS + Nigericin on top of OCHSCs induced ectopic expression of inflammation markers and enhanced neuronal excitation. In contrast, no excitability changes were detected after adding primed PBMCs, i.e. treated with LPS only, to OCHSCs. Strikingly, in the hippocampus, both immunoreactive and primed PBMCs elicited similar pro-inflammatory and pro-excitatory effects. However, when immunoreactive and primed PBMCs were cultured in the media separately from OCHSCs, only immunoreactive PBMCs gave rise to neuroinflammation and hyperexcitability in the hippocampus, whereas primed PBMCs failed to produce any significant changes. Finally, VX-765 application to OCHSCs, co-cultured with either immunoreactive or primed PBMCs, protected them from neuroinflammation and hippocampal hyperexcitability.ConclusionsOur study shows a higher susceptibility of the hippocampus to peripheral inflammation as compared to the cortex, mediated via Caspase-1-dependent signaling pathways. Thus, our findings suggest that Caspase-1 inhibition may potentially provide therapeutic benefits during hippocampal neuroinflammation and hyperexcitability secondary to peripheral innate immunity.
Evaluating the predictive value of procalcitonin, cough duration, and heat peak in severe Mycoplasma pneumoniae pneumonia
Authors: Yang Ying , Chen Liqing , Liu Yan
Published: March 2020

Objective To investigate the predictive value of risk factors for severe Mycoplasma pneumoniae pneumonia (MPP). Methods Retrospective analyses were conducted on 342 children with acute MPP hospitalized between December 2015 and December 2018. Results A total of 342 cases were including in the analyses, with most cases involving infants and preschool-aged children. Patients were categorized as general and severe MPP. Patients in the severe group had increased heat peak, fever duration, cough duration, length of hospitalization, and levels of white blood cell, neutrophils, C-reactive protein, and procalcitonin, as well as reduced levels of lymphocytes and platelets compared to the general group. Logistic regression and receiver operating characteristic curve analyses showed that increased levels of procalcitonin (>0.67 ng/mL), prolonged cough duration (>13.5 days), and heat peak above 38.4°C may be early predictors for severe MPP. Conclusions The severity of MPP effects fever, cough duration, and inflammatory response. Taking a detailed medical history and early procalcitonin measurement may help detect severe MPP.
Associations between participation in, intensity of, and time spent on leisure time physical activity and risk of inflammatory bowel disease among older adults (PA-IBD): A prospective cohort study
Authors: Rasmussen Nathalie Fogh , Bech Bodil Hammer , Rubin Katrine Hass , Andersen Vibeke
Published: March 2020

Background

Inflammatory bowel diseases (IBDs) are diseases of the immune system that share some genetic and lifestyle-related predisposing factors. Increasing incidences have been reported in all age groups. Based on experimental studies suggesting a role of physical activity on intestinal inflammation, this study aimed to investigate the association between leisure time physical activity and the risk of IBD in older adults.

Methods

The study is a prospective cohort study using Danish registry data and questionnaire data from the Danish “Diet, Cancer and Health” cohort. The outcome IBD was defined as having at least two diagnoses of Crohn’s disease or ulcerative colitis registered in the National Patient Registry during follow-up between December 1993 and May 1997 until December 2018. Cox proportional hazard models were used to estimate hazard ratios for IBD onset associated with being physically active and with levels of the metabolic equivalent of task (MET) hours/week of physical activity and hours/week spent on six types of physical activity.

Results

In total, 54 645 men and women aged 50-64 years were included, and thereof 529 cases. When comparing physically active with inactive participants measured by MET hours/week there was no statistically significant difference in risk of IBD (0.89 [0.13; 6.27]), neither when measured as participation in six types of activities. Results did not indicate any dose-response effect when comparing quartile groups of MET hours/week or of five of the six types of activities. For do-it-yourself-work, the third quartile of hours/week was associated with a higher risk of IBD compared to the second quartile (HR=1.44 [1.10 ; 1.90]. No effect modification was found.

Conclusions

There was no association between physical activity and risk of IBD when comparing physically active with inactive participants. Neither did the results indicate any dose-response effect when comparing quartile groups of MET hours/week. Do-it-yourself work, however, seemed to be associated with a higher risk of IBD when comparing the third quartile with the second quartile. The study has clinical relevance by its contribution to the explanatory field of the causes of IBD. However, further research is needed to clarify associations between physical activity and risk of IBD.
Statistical modeling of number of human deaths per road traffic accident in Oromia region, Ethiopia
Authors: Aga Merga Abdissa , Woldeamanuel Berhanu Teshome , Tadesse Mekonnen
Published: March 2020

Abstract

Background : Globally, road traffic accidents are leading causes of death among young people in general, and the main cause of death among young people aged 15–29 years. This study was conducted to identify the major factors associated with the number of human deaths by road traffic accident in the Oromia Regional State, Ethiopia.
Methods: We used data obtained from the Oromia Police Commission Bureau that have been recorded on daily basis road traffic accidents from July, 2016 - July, 2017. Count regression models were was used to assess the factors associated with the number of human deaths from traffic accidents.
Results : Of the total of 3900 road traffic accidents included in the 1188 (30.5%) were giving rise to fatal. The Hurde models were of better fit than zero inflated Poisson and zero inflated negative binomial model. Thus, the Hurdle Poisson is recommended in this study. Age of the driver 31-50 years (AOR = 0.289, 95%CI: 0.175, 0.479) and higher than 50 years of age (AOR = 0.311, 95%CI: 0.129, 0.751), driver’s years of experience 5-10 years (AOR = 0.014, 95%CI: 0.007, 0.027), and more than 10 years (AOR = 0.101, 95%CI: 0.057, 0.176), vehicle type automobile (AOR = 8.642, 95%CI: 2.7644, 27.023), vehicle years of service 5-10 years (AOR = 2.484, 95%CI: 1.194, 5.169), and more than 10 years (AOR = 2.639, 95%CI: 1.268, 5.497), type of accident, vehicle upside down (AOR = 5.560, 95%CI: 2.506, 12.336), causes of accident, turning illegal position (AOR = 0.454, 95%CI: 0.226, 0.913), area of accident, residential place (AOR = 108.506, 95%CI: 13.725, 857.798), working areas (AOR = 129.606, 95%CI: 16.448, 1021.263), near hospitals (AOR = 23.789, 95%CI: 3.038, 186.298), geographical locations, Western zones (AOR = 0.275, 95%CI: 0.167, 0.455), and South east zones (AOR = 0.624, 95%CI: 0.410, 0.950) were significant associated number of human deaths per road traffic accident factors in the study area.
Conclusion :
In this study, 30.5% of accidents were giving rise to at least one human death per road traffic accident and different associated numbers of human deaths per traffic accident factors have been identified.
Closed-loop target-controlled infusion system for propofol guided by bispectral index applied in patients undergoing shoulder arthroscopy in the beach chair position- a randomized controlled trial
Authors: Zhao Zhao , Li Junjie , Fang Yang , Nanbo Luo , Han Yang , Xinping Yang , Liangquan Peng , Wei Lu , Fang Guangguang , Daping Wang , Liu Zhiheng
Published: March 2020

Background To compare the efficacy of anesthetic depth control using closed-loop and open-loop target controlled infusion (TCI) system of propofol guided by BIS in patients undergoing shoulder arthroscopy in the beach chair position (BCP). Methods 120 patients underwent shoulder arthroscopy surgery in the BCP were randomized into two groups, the open-loop (O) group and the closed-loop (C) group. During the maintenance phase, BIS value was used as the feedback variable for TCI system of propofol in both groups. The Global score (GS) and the percentage of adequate anesthesia, the frequency of propofol regulation, and consumption of propofol were calculated. The MMSE scores of the day before and 1 day after surgery, serum GFAP and S100B proteins before anesthesia, after extubation and 1 day after surgery were compared. Results The GS and the proportion of appropriate anesthesia time were better in the group C. The percentage of overshoot time was lower in the group C. The frequency of propofol regulation was observed higher in the group C. Propofol consumption in the group C was significantly lower than that in the group O. The MMSE scores, the GFAP and S100B protein concentrations had no significant difference between the two groups. Conclusion Propofol administration using close-loop TCI system guided by BIS may increase the percentage of adequate anesthesia and shorten the percentage of overshoot time compared with open-loop TCI model in anesthesia maintenance phase in patients undergoing shoulder arthroscopy in the BCP, and do not increase the risk of POCD.
A knowledge-based intensity-modulated radiation therapy treatment planning technique for locally advanced nasopharyngeal carcinoma radiotherapy
Authors: Bai Penggang , Weng Xing , Quan Kerun , Chen Jihong , Dai Yitao , Xu Yuanji , Lin Fasheng , Zhong Jing , Wu Tianming , Chen Chuanben
Published: March 2020

Background To investigate the feasibility of a knowledge-based automated intensity-modulated radiation therapy (IMRT) planning technique for locally advanced nasopharyngeal carcinoma (NPC) radiotherapy. Methods 140 NPC patients treated with definitive radiation therapy with the step-and-shoot IMRT techniques were retrospectively selected and consisted of a knowledge library (115 patients) and a test library (25 patients). For each patient in the knowledge library, their overlap volume histogram (OVH), target volume histogram (TVH) and dose objectives were extracted from the patient’s manual treatment plan, and these were used to train a 3 layer neural network (NN) model. The OVH and TVH from the test library were input into the trained model to derive patients’ dose objectives which were subsequently used to generate automated plans (APs) by an in-house developed Perl and HotScripts planning scripts with a single iteration optimization. The corresponding manual plans (MPs) of patients in the test library were manually generated by an experienced medical physicist according to clinical protocols. Plan quality was ranked and dosimetric parameters were compared between the APs and MPs. Results Qualitatively, the APs and MPs had the same rank for the majority of the patients (19 of 25). PTV achieved each given criteria in the majority of the patients (greater than 80%) between both the APs and MPs. For each OAR, the number achieving its criterion in the APs was close to that in the MPs. The APs would improve the treatment delivery efficiency by reducing total plan MUs by ~5% (685.24±58.89 vs. 721.36±63.36, P =0.004). AP also significantly improved planning efficiency by reducing the planning duration to ~17% of the MP (9.73±1.80 min vs. 57.10±6.35 min, P <0.001). Conclusion A robust and effective knowledge-based IMRT treatment planning technique for locally advanced NPC is developed. Patient specific TDV can be predicted by a trained NN model based on the individual’s OVH and clinical TVH goals. The automated planning scripts can use these TDV to generate APs with largely shortened planning time with comparable or improved dosimetric qualities compared to our clinic’s manual plans.
Clinically oriented contour evaluation using geometric and dosimetric indices based on geometric transformation
Authors: Xian Lixun , Li Guangjun , Xiao Qing , Li Zhibin , Zhang Xiangbin , Chen Li , Hu Zhenyao , Bai Sen
Published: March 2020

Background : In radiotherapy, geometric indices are often used to evaluate the accuracy of contouring; However, the ability of geometric indices to identify the error of contouring results is limited, and there is lack of clinical background. Based on the reference contouring, we systematically introduced geometric errors to study the relationship between geometric and dosimetric indices and evaluated the clinical feasibility of assessing the accuracy of contouring based on geometric indices alone. Materials and Methods: A C-shaped target, organ at risk (Core), and intensity-modulated radiotherapy (IMRT) plan outlined in the American Association of Physicists in Medicine (AAPM) TG-119 report (The report of Task Group 119 of the AAPM) were used as references. Translation, scaling, rotation (except for the Core), and sine function transformation were performed to simulate the contouring results. The corresponding dosimetric indices were obtained from the original dose distribution of the radiotherapy plan, and correlations (R²) between geometric indices and dosimetric indices were quantified through linear regression. The clinical applicability of the threshold for geometric indices was analyzed by combining the geometric indices and dose difference diagram. Results: The correlations between the geometric and dosimetric indices were different and inconsistent for the contouring of the target and Core after the geometric transformation simulation. Except for the sine function transformation (R²: 0.04–0.023, p > 0.05), the other three geometric indices of the planning target volume (PTV) had strong correlations with the dosimetric indices D98% and D mean (R²: 0.689–0.988), 80% of which were strongly correlated with a p < 0.001. The correlation results for the other geometric transformations in the Core were similar to those in the PTV except for the down shift transformation. Conclusions: The dosimetric indices are heavily influenced by the contour differences, thus highlighting their importance in the evaluation process. Clinically, an assessment of the contour accuracy of the region of interest is not feasible based on geometric indices alone, and should be combined with dosimetric indices. Keywords: Contour evaluation, Geometric indices, Dosimetric indices, Geometric transformation simulation
Prevalence and mechanisms of carbapenem resistance among Klebsiella aerogenes in a tertiary hospital in China
Authors: Liu Luxiang , Quan Jingjing , Zhao Dongdong , Liao Weichao , Lv Jiaojian , Zhuge Huang , Zhao Feng , Yu Yunsong , Zhou Zhihui
Published: March 2020

Background: Klebsiella aerogenes has emerged as one of the most important nosocomial pathogens for patients in intensive care units (ICU) in recent years. This study aims to evaluated the prevalence and molecular characteristics of clinical carbapenem-resistant K. aerogenes (CRKA) isolates in a tertiary hospital in China.Results: Twenty CRKA were identified among all the isolates, with the rate of 5.5% (20/364). Six CRKA isolates produced KPC-2 and 1 CRKA isolate produced NDM-1. PFGE and MLST indicated that the 20 CRKA strains were clonal diversity. All the bla KPC-2 gene and bla NDM-1 gene were located on plasmids and all the plasmids with bla KPC-2 and bla NDM-1 genes could successfully transferred to EC600 or J53. Twelve of 13 CRKA strains without any carbapenemase genes were positive for efflux pump inhibition test.Conclusion: Overall, the prevalence of CRKA in the tertiary hospital in Zhejiang Province of China is 5.5%. Only 35% of CRKA produce carbapenemase and efflux pumps might play an important role in the carbapenem resistance of K. aerogenes. It is necessary to strengthen the surveillance of carbapenem resistance in the hospital to prevent the horizontal and clonal spread of CRKA.
GPs perspective on the usability of the Dutch Primary Care Practice Report: a qualitative interpretative approach
Authors: Bekker Piet De , Vink Maarten , Donker Marianne , Sterkenburg Paul , Hijden Eric van der
Published: March 2020

Background Audit and feedback informs healthcare providers and may affect professional practice and patient outcomes. The Primary Care Practice Report (PCPR) is a web based personalized feedback instrument for general practitioners (GPs) in the Netherlands, based on claims data. Its yearly uptake is limited. In order to improve the use and usability of the report this study aims to identify key criteria that GPs deem important for audit and feedback.Methods A qualitative interpretative approach was used. We interviewed 12 GPs about their use of the practice report. These interviews followed the Three-Step Test-Interview method. Thematic content analysis was used to investigate the perception of the GP on the report and their perspective on the usability. The interviews resulted in critical items for audit and feedback, on which all tables and graphs in the report were systematically assessed.Results From the interviews with GPs recurring criteria emerged that were identified as decisive for the effectiveness of performance feedback: content, reliability, validity and usability. The 34 tables and graphs of the PCPR were assessed using factual characteristics. Content analysis shows that the PCPR has a strong focus on costs. Assessment on validity indicates that casemix correction is always performed if relevant, but explanatory notes hardly clarify which (sub)population is measured (3/34), therefore GP’s in general have difficulty interpreting the results. Assessment on usability shows that, although benchmark figures are almost always presented based on national references, the formulation of goals or any specific attention for an action perspective is lacking because the perceived comparability with the patient group of the GP is limited.Conclusions The current PCPR does not meet key criteria for effective audit and feedback, as defined by GPs. It has a strong focus on costs instead of clinical behavior and is poorly understood when it comes to the specific population the data reflect. The results are in line with theoretical perspectives on learning and improvement of professionals. Improvement of the PCPR requires information on aspects of clinical behavior that are recognizable for GPs and they actually can influence. First steps are made to improve the method of case-mix correction in the benchmarking.
Adapting the Sudden Landslide Identification Product (SLIP) and Detecting Real-Time Increased Precipitation (DRIP) algorithms to map and predict rainfall-triggered landslides in the West-Cameroons’ highlands (Central-Africa)
Authors: MFONDOUM ALFRED HOMERE NGANDAM , Nguet Pauline Wokwenmendam , Mfondoum Jean Valery Mefire , Tchindjang Mesmin , Hakdaoui Sofia , Cooper Ryan , Gbetkom Paul Gérard , Penaye Joseph , Bekoa Ateba , Moudioh Cyriel
Published: March 2020

Background – The SLIP and DRIP algorithms recently developed correlate Landsat 8 images and local daily precipitation records to map and time rainfall-triggered landslides. In many areas recently affected by that geohazard in west-Cameroon’s highlands, only the dry season images are available, while rainfall data are recorded on a monthly scale.
Methods – The SLIP algorithm is modified, integrating the inverse NDVI to assess the soil exposure, the Modified Normalized Multi-band Drought Index (MNMDI) combined with the hydrothermal index to assess soil moisture, and the slopes in degrees. They are converted into binned layers and overlaid to map the recent landslide. The DRIP algorithm is also modified, using the monthly rainfall rescaled to a daily window and the days of rainfall per month. Their probability density function (PDF) curves are superimposed and their intersection are used to propose set dichotomous variables before and after the 28 October 2019 landslide event, for a prediction model.
Results – The Landslide Hazard Zonation (LHZ) map of latest landslides is effective at 100% , while the overall accuracy is 77.8% when integrating the control point around the disaster area. Moreover, for 1948-2018 individual thresholds of , and 2019 threshold of between June and October, the risk of rainfall-triggered landslide is 95% , while the 'no-landslide' probabilities are between 98.95% and 99.99% .
Conclusions – Based on the SLIP and DRIP algorithms, the proposed methodology offers a new alternative in case of voids and gaps between data. Improvements and comparisons with others models are in perspective.
Keywords – SLIP, DRIP, Landsat 8, geohazard, West-Cameroons’ Highlands, rainfall-triggered Landslides, LHZ, prediction model.
Factors Associated with Physical Activity in Elderly Nursing Home Residents: A Path Analysis
Authors: Huang Jingxin , Zou Youqing , Huang Wentao , Zhou Ye , Lin Shanshan , Chen Jiaojiao , Lan Yutao
Published: March 2020

Background: Physical activity (PA) is low among elderly residents in nursing homes in China. We aimed to determine the factors that influence PA among elderly nursing home residents and their direct or indirect effects on PA levels.Methods: The PA levels of the participants were measured using the International Physical Activity Questionnaire, and their health beliefs were assessed using a self-developed 18-item questionnaire titled the ‘Health Beliefs of Nursing Home Residents Regarding Physical Activity,’ in accordance with Health Belief Model (HBM) constructs. The correlations between HBM constructs and PA levels were analyzed and a regression-based path analysis was conducted to examine the relationships between HBM constructs and PA levels.Results: A total of 180 residents with a mean age of 82.5 years (standard deviation = 5.76) were recruited. Linear regression analysis revealed that self-efficacy (p<0.001), perceived severity (p<0.01), and cues to action (p<0.01) were associated with the level of PA among nursing home residents. In the conceptual path model, self-efficacy, perceived severity, and cues to action had positive direct effects on PA level, while perceived benefits and perceived barriers had indirect effects on the PA level.Conclusion: The residents’ self-efficacy, perceived severity, and cues to action were found to be important factors that can affect the design and implementation of educational programs for PA. A better understanding of such associations may help healthcare providers design informed educational interventions to increase PA levels among nursing home residents.
Can judgments according to case fatality rate be correct all the time during epidemics? Some lessons from Coronavirus 2019-nCoV case fatality rate index in Iran
Authors: Piroozi Bakhtiar , Moradi Ghobad , Mohamadi-Bolbanabad Amjad , Safari Hossein
Published: March 2020

Background: Coronavirus 2019-nCoV was first identified in China in 2019. One of the most important indices noticed by experts, policymakers and managers which is daily evaluated in epidemics and a lot of judgments are made based on it, is case fatality rate (CFR) index of the disease. CFR can change during epidemics. This study aims to calculate CFR index for nCov-2019 in Iran and answer the following question: Is it right to base judgment on CFR all the time during epidemics and is it right to judge based on that since the outbreak of an epidemic?Methods: This research is a descriptive study. Its required data was obtained from the website of The Ministry of Health and Medical Education of Iran from February 20th 2020 until March 14th 2020. CFR index was calculated when the death toll of a disease is divided by the total number of people infected by that disease. Excel 2013 software was used to a1nalyze the data.Results: According to the findings of this study, In Iran, until March 14th 2020, 11364 people have been infected by Coronavirus 2019-nCoV and 514 people died of it. CFR index had a descending trend and it was 100%, 18.6%, 8.8%, 3.1%, 3.3%, 4.5% on the first, fifth, tenth, fifteenth, twentieth and twenty fifth day, respectively. Conclusion: In emerging epidemics, an index must not be based to judge a health system’s performance until that epidemics condition has not been clarified. It would be suggested that in the outbreak of an epidemic, specifically emerging diseases, CFR must not be the base of judgment. Making judgments, specifically, in the outbreak of emerging epidemics based on fatality rate can lead to an information bias.
Single tree crown shape and volume models for Pinus nigra planted forests in Italy to support forest management strategies in artificial stands
Authors: Salvatore Umberto Di , Marchi Maurizio , Cantiani Paolo
Published: March 2020

Background Tree crown can be considered the engine of trees whose size is a key variable to understand the most important ecological and physiological processes that occur in forest ecosystem. The shape and dimension of single-tree crown are affected by a combination of multiple factors such as lateral competition, fertility as well as forest management practices. Anyway, few models are provided in literature to derive their shape and volume from sampled data except the light transmittance or light measurements under canopy closure (Photosynthetic Active Radiation or Leaf Area Index). The main goal of the study is to present a simple and effective method to predict crown shape and crown volume in artificial black pine plantations in Italy from simple field data. Two key parameters involved in crown volume calculation in literature were here modelled. Such parameters were the distance from the top where the crown expresses its the maximum radius (L 0 ) and the radius at crown base height (r cb ). The analysis of crown profile and volume is based on available knowledge we found in literature (Pretzsch 2009) and where the considered species was not included. Results The nonlinear equation results the most adequate for the fitting and able to characterise the ecological processes more properly. Even if just slightly different, the mean absolute error was lower and statistically significant and around 84 cm for L 0 and 36 cm for r cb . Then the use of a modelling procedure also allowed the calculation of confidence intervals and was more powerful than a single multiplier, which is the most common method available in literature. Once compared with field data collected during thinning harvesting, the calculated volumes were correlated with thinning intensities and able to characterise the number of trees removed in each treatment and the increased amount of PAR on the ground. Conclusions The proposed model results useful to evaluate the spatial structure of forest stand without sophisticated and time-consuming surveys and could be an additional tool to support the practical management of artificial black pine stands.
Characteristics of Symptomatic and Asymptomatic Bacteriuria in Patients with Neurogenic Bladder under Neurorehabilitation
Authors: Lopes Fauster O. B. , Bomfim Maria Rosa Q. , Monteiro Sílvio G. , Silva Marcello T. da , Pinho Virginia Maria L. S. de , Aires Raimundo José D. , Carvalho Roberto M. L. de , Monteiro-Neto Valerio
Published: March 2020

Background: The definitions of urinary tract infections (UTI) and asymptomatic bacteriuria (ABU) are problematic to apply in patients with neurogenic bladder (NB). Here, we carried out a comparative analysis of the main clinical and laboratory data of NB patients with UTI and ABU.Methods: One hundred ninety five patients with neurogenic bladder were evaluated in the Urology Sector at a neurorehabilitation hospital. Patients were divided into either ABU or UTI group based on clinical and laboratory data. The sociodemographic data, clinical history, and laboratory test results were collected and used in the comparative analysis.Results: Of the patients evaluated, 161 (82.6%) had ABU. Patients of different age groups were affected, predominantly young adults (20-39 years). The median time of bladder involvement was 8.9 years (0-35). Neurogenic bowel was observed in 97.5% of cases and renal lithiasis in 11.3%. The main underlying pathologies leading to urologic involvement were spinal cord injury, myelomeningocele, stroke, and neoplasms. Only 16.4% of patients were not on intermittent catheterization, in which the risk of recurrent infection was higher than in patients who were under for intermittent bladder catheterization (p = 0.016, OR 2.65). Infection rates were significantly different between patients with histories of recurrent urinary tract infections (asymptomatic bacteriuria 29.8% vs 52.9% infection, p = 0.016). Leukocyturia was frequent in both groups, however, our data suggested that only values ≤ 30 cells/high power field excluded infection.Conclusions: In summary, intermittent catheterization was observed to be essential in the prevention of recurrent UTI, as well as the need to adjust the reference values for leukocyturia in the definition of the infectious condition.
Individualized treatment for acute Achilles tendon rupture based on the Copenhagen Achilles Rupture Treatment Algorithm (CARTA): a study protocol for a multicenter randomized controlled trial
Authors: Hansen Maria Swennergren , Vestermark Marianne Toft , Hölmich Per , Kristensen Morten Tange , Barfod Kristoffer Weisskirchner
Published: March 2020

Background: An individualized treatment algorithm (Copenhagen Achilles Rupture Treatment Algorithm - CARTA) based on the ultrasonographic appearance of an acute Achilles tendon rupture has been developed aiming to select the correct patients for operative and non-operative treatment. The objective of this study is to investigate if this individualized treatment algorithm gives a better functional outcome than treating all patients either operatively or non-operatively per default. Methods: This study is conducted as a multicenter three-armed randomized controlled trial. Participants are included from four hospitals in Denmark and randomized 1:1:1 to one of three parallel groups: 1) Intervention group: Participants are treated according to an individualized treatment algorithm,2) Control group A: Participants are treated non-operative, 3) Control group B: Participants are treated operative. The individualized treatment algorithm for the intervention group is based on an ultrasonographic examination; tendon overlap and elongation below 7% is to be treated non-operative, while no tendon overlap and and/or elongation above 7% will be treated operative. 300 participants will be included over a period of 3 years. The primary outcome is the heel-rise work test at 12 months post-injury. Secondary outcomes are tendon elongation, the Achilles tendon Total Rupture Score (ATRS), the rate of re-ruptures and other complications. The primary analysis will be conducted as intention-to-treat analysis. Discussion: This trial will indicate if treatment of acute Achilles tendon rupture can be individualized based on the elongation and tendon overlap. It is hypothesized that different patients will benefit from different treatment instead of offering all the same treatment. Trial registration: ClinicalTrials.gov Identifier: NCT03525964. Registered 16 May 2018. Keywords: Achilles tendon, Achilles tendon rupture, individualized treatment, ultrasound.
Timing of antiretroviral therapy for HIV-infected patients with moderate-to-severe Pneumocystis pneumonia: study protocol for a multi-center prospective randomized controlled trial
Authors: Qin Yuanyuan , Lu Yanqiu , Zhou Yihong , Harypursat Vijay , Sun Feng , Yang Sen , Tang Shengquan , Li Yao , He Xiaoqing , Zeng Yanming , Chen Yaokai
Published: March 2020

Background: Pneumocystis pneumonia (PCP) is a common AIDS-related opportunistic infection. Recent reports estimate that more than 400,000 HIV patients develop PCP each year globally. However, the timing of antiretroviral therapy (ART) initiation for HIV infected patients with PCP is still controversial, and the benefits and risks of early initiation of ART are not completely clear. We thus designed this study in order to determine the optimal timing for ART initiation for HIV-positive patients with moderate to severe PCP.Methods: This study will be an open-labelled, multi-center, prospective, randomized controlled trial. A total of 200 subjects will be randomized to an early ART initiation group (≤14 days after PCP diagnosis), and a deferred ART initiation group (>14 days after PCP diagnosis) at a 1:1 ratio. All subjects will be followed up for 48 weeks after starting ART. The primary outcome is incidence of disease progression (including new opportunistic infections and all-cause mortality) at week 48. The secondary endpoints are the changes in CD4 counts from baseline at week 12, week 24 and week 48, the degree of virological suppression (HIV-RNA<50 copies/mL) at week 24 and week 48, the rate of development of PCP-associated immune reconstitution inflammatory syndrome (IRIS), and adverse events(AEs) at each visit.Discussion: We hope that the results of this study will reveal the optimal timing for initiation of ART in HIV-infected patients with moderate to severe PCP.Trial registration: This trial was registered as one of the twelve trials under the name of a general project at chictr.org.cn on February 1, 2019, and the registration number of the general project is ChiCTR1900021195.