bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of a trauma quality-of-life follow-up clinic
Authors: Trevino Colleen , Geier Timothy , Timmer-Murillo Sydney C. , Shawlin Matthew , Milia David J. , Codner Panna , deRoon-Cassini Terri
Published: March 2020

BACKGROUND

Little effort has been made to address long-term quality of life, chronic pain (CP), posttraumatic stress disorder (PTSD), and functional disability in trauma survivors. This quality initiative was developed to determine feasibility of a coordinated, comprehensive, patient-centered follow-up clinic for those at risk for poor long-term outcomes.

METHODS

A convenience sample from 649 hospitalized trauma patients at a Midwestern level 1 trauma center between February 2018 and August 2018 was screened for risk of PTSD and CP. Thirty-six patients were randomized into a standard follow-up clinic (standard of care [SOC]) (2-week postdischarge surgical clinic) or a new trauma quality of life clinic (TQOL). The TQOL was developed to provide comprehensive care to patients at high risk for PTSD (Injured Trauma Survivor Score, ≥2) and/or CP (discharge pain score, ≥4). Trauma quality of life clinic included a nurse practitioner or surgeon (physician), psychologist, social worker, and physical therapist at 1-week post discharge. All providers saw the patient independently, developed a care plan collaboratively, and communicated the plan to the patient. The SOC involved a visit only with a nurse practitioner or surgeon (medical doctor). Measures of pain, PTSD, depression, quality of life, physical functioning, and life satisfaction were completed at time of the TQOL/SOC or over the phone.

RESULTS

There were no differences in demographics, readmissions, or emergency department visits after discharge between groups. However, no show rates were almost twice as high in SOC (40%) compared with TQOL (22%) and those in TQOL completed 23 additional psychology visits versus one psychology visit in SOC. This clinic structure is feasible for high-risk patients, and TQOL patients demonstrated improved engagement in their care.

CONCLUSIONS

A comprehensive multidisciplinary TQOL addressing issues affecting convalescence for trauma patients at high risk for developing PTSD and CP can improve follow-up rates to ensure patients are recovering successfully.

LEVEL OF EVIDENCE

Therapeutic, Level IV.
Origin, genomic diversity and microevolution of the Clostridium difficile B1/NAP1/RT027/ST01 strain in Costa Rica, Chile, Honduras and Mexico
Authors: Guerrero-Araya Enzo , Meneses Claudio , Castro-Nallar Eduardo , Guzmán D. Ana M. , Álvarez-Lobos Manuel , Quesada-Gómez Carlos , Paredes-Sabja Daniel , Rodríguez César
Published: March 2020

Clostridium difficile

B1/NAP1/RT027/ST01 has been responsible for outbreaks of antibiotic-associated diarrhoea in clinical settings worldwide and is associated with severe disease presentations and increased mortality rates. Two fluoroquinolone-resistant (FQR) lineages of the epidemic B1/NAP1/RT027/ST01 strain emerged in the USA in the early 1990s and disseminated trans continentally (FQR1 and FQR2). However, it is unclear when and from where they entered Latin America (LA) and whether isolates from LA exhibit unique genomic features when compared to B1/NAP1/RT027/ST01 isolates from other regions of the world. To answer the first issue we compared whole-genome sequences (WGS) of 25 clinical isolates typed as NAP1, RT027 or ST01 in Costa Rica (n=16), Chile (n=5), Honduras (n=3) and Mexico (n=1) to WGS of 129 global isolates from the same genotype using Bayesian phylogenomics. The second question was addressed through a detailed analysis of the number and type of mutations of the LA isolates and their mobile resistome. All but two B1/NAP1/RT027/ST01 isolates from LA belong to the FQR2 lineage (n=23, 92 %), confirming its widespread distribution. As indicated by analysis of a dataset composed of 154 WGS, the B1/NAP1/RT027/ST01 strain was introduced into the four LA countries analysed between 1998 and 2005 from North America (twice) and Europe (at least four times). These events occurred soon after the emergence of the FQR lineages and more than one decade before the first report of the detection of the B1/NAP1/RT027/ST01 in LA. A total of 552 SNPs were identified across all genomes examined (3.8–4.3 Mb) in pairwise comparisons to the R20291 reference genome. Moreover, pairwise SNP distances were among the smallest distances determined in this species so far (0 to 55). Despite this high level of genomic conservation, 39 unique SNPs (7 %) in genes that play roles in the infection process (i.e. slpA) or antibiotic resistance (i.e. rpoB, fusA) distinguished the LA isolates. In addition, isolates from Chile, Honduras and Mexico had twice as many antibiotic resistance genes (ARGs, n=4) than related isolates from other regions. Their unique set of ARGs includes a cfr-like gene and tetM, which were found as part of putative mobile genetic elements whose sequences resemble undescribed integrative and conjugative elements. These results show multiple, independent introductions of B1/NAP1/RT027/ST01 isolates from the FQR1 and FQR2 lineages from different geographical sources into LA and a rather rapid accumulation of distinct mutations and acquired ARG by the LA isolates.
Evaluating the effect of public health intervention on the global-wide spread trajectory of Covid-19
Authors: Hu Zixin , Ge Qiyang , Li Shudi , Jin Li , Xiong Momiao
Published: March 2020

As COVID-19 evolves rapidly, the issues the governments of affected countries facing are whether and when to take public health interventions and what levels of strictness of these interventions should be, as well as when the COVID-19 spread reaches the stopping point after interventions are taken. To help governments with policy-making, we developed modified auto-encoders (MAE) method to forecast spread trajectory of Covid-19 of countries affected, under different levels and timing of intervention strategies. Our analysis showed public health interventions should be executed as soon as possible. Delaying intervention 4 weeks after March 8, 2020 would cause the maximum number of cumulative cases of death increase from 7,174 to 133,608 and the ending points of the epidemic postponed from Jun 25 to Aug 22.
Pan-resistome characterization of uropathogenic Escherichia coli and Klebsiella pneumoniae strains circulating in Uganda and Kenya isolated from 2017-2018
Authors: Decano Arun Gonzales , Pettigrew Kerry , Sabiiti Wilber , Sloan Derek , Neema Stella , Bazira Joel , Kiiru John , Onyango Hellen Atieno , Asiimwe Benon , Holden Matthew T. G.
Published: March 2020

Background

Urinary tract infection (UTI) develops after a pathogen adhered to the inner lining of the urinary tract. Cases of UTIs are predominantly caused by several Gram-negative bacteria and account for high morbidity in the clinical and community settings. Of greater concern are the strains carrying antimicrobial resistance (AMR)-conferring genes. The gravity of UTI is also determined by a spectrum of other virulence factors. This study represents a pilot project to investigate the burden of AMR among uropathogens in East Africa.

Methods

We examined bacterial samples isolated in 2017-2018 from in- and out-patients in Kenya (KY) and Uganda (UG) that presented with clinical symptoms of UTI. We reconstructed the evolutionary history of the strains, investigated their population structure and performed comparitive analysis their pangenome contents.

Results

We found 55 Escherichia coli and 19 Klebsiella pneumoniae strains confirmed uropathogenic following screening for the prevalence of UTI virulence genes including fimH, iutA, feoA/B/C, mrkD and foc. We identified 18 different sequence types in E. coli population while all K. pneumoniae strains belong to ST11. The most prevalent E. coli sequence types were ST131 (26%), ST335/1193 (10%) and ST10 (6%). Diverse plasmid types were observed in both collections such as Incompatibility (IncF/IncH/IncQ1/IncX4) and Col groups. Pangenome analysis of each set revealed a total of 2,862 and 3,464 genes comprised the core genome of E. coli and K. pneumoniae population, respectively. Among these are AMR determinants including fluoroquinolone resistance-conferring genes aac(3)-Ib-cr and other significant genes: aad, tet, sul1, sul2, and cat, which are associated with aminoglycoside, tetracycline, sulfonamide and chloramphenicol resistance. Accessory genomes of both species collection were detected several β-lactamase genes, blaCTX-M, blaTEM and blaOXAor blaNDM.Overall, 93% are multi-drug resistant in the E. coli collection while 100% of the K. pneumoniae strains contained genes that are associated with resistance to 3 or more antibiotic classes.

Conclusions

Our findings illustrate the abundant resistome and virulome repertoire in uropathogenic E. coli and K. pneumoniae, which are mainly disseminated via clonal and horizontal transfer, circulating in the East African region. We further demonstrate here that routine genomic surveillance is necessary for high-resolution bacterial epidemiology of these important AMR pathogens.
Heat inactivation of serum interferes with the immunoanalysis of antibodies to SARS-CoV-2
Authors: Hu Xiumei , An Taixue , Situ Bo , Hu Yuhai , Ou Zihao , Li Qiang , He Xiaojing , Zhang Ye , Tian Peifu , Sun Dehua , Rui Yongyu , Wang Qian , Ding Dan , Zheng Lei
Published: March 2020

The detection of serum antibodies to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is emerging as a new tool for the coronavirus disease-2019 (COVID-19) diagnosis. Since many coronaviruses are sensitive to heat, heating inactivation of samples at 56 °C prior to testing is considered a possible method to reduce the risk of transmission, but the effect of heating on the measurement of SARS-CoV-2 antibodies is still unclear. By comparing the levels of SARS-CoV-2 antibodies before and after heat inactivation of serum at 56 °C for 30 minutes using a quantitative fluorescence immunochromatographic assay, we shown that heat inactivation significantly interferes with the levels of antibodies to SARS-CoV-2. The IgM levels of all the 34 serum samples (100%) from COVID-19 patients decreased by an average level of 53.56%. The IgG levels were decreased in 22 of 34 samples (64.71%) by an average level of 49.54%. Similar changes can also be observed in the non-COVID-19 diseases group (n=9). Of note, 44.12% of the detected IgM levels were dropped below the cut-off value after heating, suggesting heat inactivation can lead to false-negative results of these samples. Our results indicate that heat inactivation of serum at 56 °C for 30 minutes interferes with the immunoanalysis of antibodies to SARS-CoV-2. Heat inactivation prior to immunoanalysis is not recommended and the possibility of false-negative results should be considered if the sample was pre-inactivated by heating.
Triaging patients in the outbreak of the 2019 novel coronavirus
Authors: Huang Guoqing , Zeng Weiqian , Wang Wenbo , Song Yanmin , Mo Xiaoye , Li Jia , Wu Ping , Wang Ruolong , Zhou Fangyi , Wu Jing , Yi Bin , Xiong Zeng , Zhou Lu , Wang Fanqi , Tian Yangjing , Hu Wenbao , Xu Xia , Zhai Ruonan , Yuan Kai , Li Xiangmin , Qiu Xinjian , Qiu Jian , Wang Aimin
Published: March 2020

In the end of 2019, the epidemic of a new coronavirus (SARS-CoV-2) occurred in Wuhan and spread rapidly. Changsha, a city located south to the epicenter, was soon impacted. To control the transmission of the coronavirus and avoid nosocomial infection, triage procedures based on epidemiology were implemented in a local hospital of the city. This retrospective study analyzed the data collected during the triage period and found that COVID-19 patients were enriched seven folds into the Section A designated for rapid detection and quarantine. On the other side, roughly triple amounts of visits were received at the Section B for patients without obvious epidemiological history. Eight COVID-19 cases were spotted out of 247 suspected patients. More than 50% of the suspected patients were submitted to multiple rounds of nucleic acid analysis for SARS-CoV-2 infection. Of the 239 patients who were diagnosed as negative of the virus infection,188 were successfully revisited and none was reported as a COVID-19 case. Of the eight COVID-19 patients, three were confirmed only after multiple rounds of nucleic acid analysis. Besides comorbidities, delayed sharing of epidemiological history added another layer of complexity to the diagnosis in practice. While SARS-CoV-2 epidemic is being alerted in many countries, our report will be helpful to other colleagues in rapid identification of COVID-19 cases and controlling the transmission of the disease.
De-novo purine biosynthesis is a major driver of chemoresistance in glioblastoma
Authors: Shireman Jack M , Atashi Fatemeh , Lee Gina , Ali Eunus S. , Saathoff Miranda R. , Park Cheol H. , Baisiwala Shivani , Miska Jason , Lesniak Maciej S. , David James C. , Stupp Roger , Kumthekar Priya , Horbinski Craig M. , Ben-Sahra Issam , Ahmed Atique U.
Published: March 2020

This year nearly 20,000 lives will be lost to Glioblastoma (GBM), a treatment-resistant primary brain cancer. In this study, we identified a molecular circuit driven by epigenetic regulation that regulates the expression of ciliary protein ALR13B. We also demonstrated that ARL13B subsequently interacts with purine biosynthetic enzyme IMPDH2. Removal of ARL13B enhanced TMZ-induced DNA damage by reducing de-novo purine biosynthesis and forcing GBM cells to rely on the purine salvage pathway. Furthermore, targeting can be achieved by using an FDA-approved drug, Mycophenolate Moefitil. Our results suggest a clinical evaluation of MMF in combination with TMZ treatment in glioma patients.
LZTR1 inactivation promotes MAPK/ ERK pathway activation in glioblastoma by stabilizing oncoprotein RIT1
Authors: Wang Yuqi , Zhang Jianong , Zhang Pingzhao , Zhao Zhipeng , Huang Qilin , Yun Dapeng , Chen Juxiang , Chen Hongyan , Wang Chenji , Lu Daru
Published: March 2020

Large-scale sequencing studies on glioblastoma have identified numerous genetic alterations. Leucine-zipper-like transcription regulator 1 (LZTR1) is inactivated by non-synonymous mutations and copy number losses, suggesting that it is a tumor suppressor in glioblastoma. However, howLZTR1mutations contribute to glioblastoma pathogenesis remains poorly understood. Here, we revealed that LZTR1, as an adaptor of the CUL3 E3 ubiquitin ligase complex, recognizes and triggers ubiquitin-dependent degradation of oncoprotein RIT1, a RAS-like GTPase. Wild-type LZTR1 suppresses glioblastoma cell proliferation and migration by inactivating the MAPK/ERK signaling pathway in a RIT1-dependent manner. However, the effects were abrogated by the glioblastoma-associated LZTR1 mutations. Our findings revealed the underlying molecular mechanism of LZTR1 mutations-driven glioblastoma, and provide novel therapeutic target for LZTR1 mutations-driven glioblastoma.
Connexin 43 hemichannels mediate spatial and temporal disease spread in ALS
Authors: Almad Akshata A. , Taga Arens , Joseph Jessica , Welsh Connor , Patankar Aneesh , Gross Sarah K. , Richard Jean-Philippe , Pokharel Aayush , Lillo Mauricio , Dastgheyb Raha , Eggan Kevin , Haughey Norman , Contreras Jorge E. , Maragakis Nicholas J.
Published: March 2020

Connexin 43 (Cx43) gap junctions and hemichannels mediate astrocyte intercellular communication in the central nervous system under normal conditions and may contribute to astrocyte-mediated neurotoxicity in amyotrophic lateral sclerosis (ALS). Here we show that astrocyte-specific knockout of Cx43 in a mouse model of ALS slows disease progression both spatially and temporally, provides motor neuron (MN) protection, and improves survival. In human ALS tissues and biofluids, we observe that higher levels of Cx43 correlate with accelerated disease progression. Using human iPSC-derived astrocytes (hiPSC-A) from both familial and sporadic ALS, we show that Cx43 is upregulated and that Cx43-hemichannels are enriched at the astrocyte membrane. We then demonstrate that the pharmacological blockade of Cx43-hemichannels in ALS astrocytes, during a specific temporal window, provides neuroprotection of hiPSC-MN and reduces ALS astrocyte-mediated neuronal hyperexcitability. Our data identify Cx43 hemichannels as novel conduits of astrocyte-mediated disease progression and a pharmacological target for disease-modifying ALS therapies.
Evolutionary Pressures and Codon Bias in Low Complexity Regions of Plasmodia Parasites
Authors: Cappannini Andrea , Forcelloni Sergio , Giansanti Andrea
Published: March 2020

One of the most debated topics in Evolutionary Biology concerns Low Complexity Regions of P. falciparum, the causative agent of the most virulent and deadly form of human malaria. In this work, we analysed the proteome of 22 plasmodium species including P. falciparum. SEG predicts that proteins containing Low Complexity Regions turn out to be longer than those which are predicted to be completely complex (without Low Complexity Regions). Moreover, using some well-known bioinformatics tools such as the Effective Number of Codons, the Pr2 and a new index that we have called SPI, we have noticed how proteins that embed Low Complexity Regions are under lower selective pressure than those that do not present this type of locus. By applying the Relative Synonymous Codon Usage and other tools developed ad hoc for this study, we note, instead, how the Low Complexity Regions appear to have a non-neutral codon bias with respect to the host proteins.
The biomechanical role of extra-axonemal structures in shaping the flagellar beat of Euglena
Authors: Cicconofri Giancarlo , Noselli Giovanni , DeSimone Antonio
Published: March 2020

We propose and discuss a model for flagellar mechanics inEuglena gracilis. We show that the peculiar non-planar shapes of its beating flagellum, dubbed “spinning lasso”, arise from the mechanical interactions between two of its inner components, namely, the axoneme and the paraflagellar rod. The spontaneous shape of the axoneme and the resting shape of the paraflagellar rod are incompatible. The complex non-planar configurations of the coupled system emerge as the energetically optimal compromise between the two antagonistic components. The model is able to reproduce the experimentally observed flagellar beats and their characteristic spinning lasso geometric signature, namely, travelling waves of torsion with alternating sing along the length of the flagellum.
Asperosaponin VI inhibits LPS-induced inflammatory response by activating PPAR-γ pathway in primary microglia
Authors: Zhang Jinqiang , Yi Saini , Xiao Chenghong , Li Yahui , Liu Chan , Jiang Weike , Yang Changgui , Zhou Tao
Published: March 2020

Microglia cells are the main mediators of neuroinflammation. Activation of microglia often aggravates the pathological process of various neurological diseases. Natural chemicals have unique advantages in inhibiting microglia-mediated neuroinflammation and improving neuronal function. Here, we examined the effects of asperosaponin VI (ASA VI) on LPS-activated primary microglia. Microglia were isolated from mice and pretreated with different doses of ASA VI, following lipopolysaccharide (LPS) administration. Activation and inflammatory response of microglia cells were evaluated by q-PCR, immunohistochemistry and ELISA. Signaling pathways were detected by western blotting. We found that the ASA VI inhibited the morphological expansion of microglia cells, decreased the expression and release of proinflammatory cytokines, and promoted the expression of antiinflammatory cytokines in a dose-dependent manner. ASA VI also activated PPAR-γ signaling pathway in LPS-treated microglia. The anti-inflammatory effects of ASA VI in microglia were blocked by treating PPAR-γ antagonist (GW9662). These results showed that ASA VI promote the transition of microglia cells from proinflammatory to anti-inflammatory by regulating PPAR-γ pathway.
Targeting CXCR1 and CXCR2 to overcome radiotherapy resistance in PTEN-deficient prostate carcinoma
Authors: Armstrong Chris W.D. , Coulter Jonathan A. , Ong Chee Wee , Maxwell Pamela J. , Walker Steven , Butterworth Karl T. , Lyubomska Oksana , Berlingeri Silvia , Gallagher Rebecca , O’Sullivan Joe M. , Jain Suneil , Mills Ian G. , Prise Kevin M , Bristow Robert G. , LaBonte Melissa J. , Waugh David J.J.
Published: March 2020

ABSTRACT

Functional impairment of the tumour-suppressorPTENis common in primary-prostate cancer and has been linked to relapse post-radiotherapy (RT). Pre-clinical modelling supports elevated CXC-chemokine signaling as a critical mediator ofPTEN-depleted disease progression and therapeutic resistance. We assessed the correlation ofPTEN-deficiency with CXC-chemokine signaling and its association with clinical outcomes. Gene expression analysis characterized aPTENLOW/CXCR1HIGH/CXCR2HIGHcluster of tumors that associates with earlier time-to-biochemical recurrence (HR 5.87 and HR 2.65 respectively) and development of systemic metastasis (HR 3.51).In vitro, CXCL-signaling was further amplified following exposure ofPTEN-deficient prostate cancer cell lines to ionizing radiation (IR). Inhibition of CXCR1/2-signaling inPTEN-depleted cell-based models increased IR-sensitivity.In vivo, administration of a CXCR1/2-targeted pepducin (x1/2pal-i3), or CXCR2-specific antagonist (AZD5069), in combination with IR toPTEN-deficient xenografts attenuated tumor growth and progression compared to control or IR alone. Post-mortem analysis confirmed that x1/2pal-i3 administration attenuated IR-induced CXCL-signaling and anti-apoptotic protein expression. Interventions targeting CXC-chemokine signaling may provide an effective strategy to combine with radiotherapy, in both locally-advanced and oligometastatic-prostate cancers, with known presence ofPTEN-deficient foci.
Supramolecular structure, in vivo biological activities and molecular-docking-based potential cardiotoxic exploration of aconine hydrochloride monohydrate as a novel salt form
Authors: Li Han-qing , Xu Jia-yin , Gao Yuan-yuan , Jin Liang , Chen Jian-ming , Chen Feng-zheng
Published: March 2020

Despite the high profile of aconine in WuTou injection, there has been no preparative technology or structural studies of its salt as the pharmaceutical product. The lack of any halide salt forms is surprising as aconine contains a tertiary nitrogen atom. In this work, aconine was prepared from the degradation of aconitine in Aconiti kusnezoffii radix (CaoWu). A green chemistry technique was applied to enrich the lipophilic-poor aconine. Reaction of aconine with hydrochloride acid resulted in protonation of the nitrogen atom and gave a novel salt form (C25H42NO9
+·Cl−·H2O; aconine hydrochloride monohydrate, AHM), whose cation in the crystal structure was elucidated based on extensive spectroscopic and X-ray crystallographic analyses. The AHM crystal had a Z′ = 3 structure with three independent cation–anion pairs, with profound conformational differences among the aconine cations. The central framework of each aconine cation was compared with that of previously reported aconitine, proving that protonation of the nitrogen atom induced the structure rearrangement. In the crystal of AHM, aconine cations, chloride anions and water molecules interacted through inter-species O—H...Cl and O—H...O hydrogen bonds; this complex hydrogen-bonding network stabilizes the supramolecular structure. The seriously disordered solvent molecules were treated using the PLATON SQUEEZE procedure [Spek (2015). Acta Cryst. C71, 9–18] and their atoms were therefore omitted from the refinement. Bioactivity studies indicated that AHM promoted in vitro proliferative activities of RAW264.7 cells. Molecular docking suggested AHM could target cardiotoxic protein through the hydrogen-bonding interactions. The structural confirmation of AHM offers a rational approach for improving the pharmaceutical technology of WuTou injection.
Simultaneous determination of maximum acceleration and endurance of morphing UAV with ABC algorithm-based model
Authors: Konar Mehmet
Published: March 2020

Purpose

The purpose of this paper is to present a novel approach based on the artificial bee colony (ABC) algorithm aiming to achieve maximum acceleration and maximum endurance for morphing unmanned aerial vehicle (UAV) design.

Design/methodology/approach

Some of the most important issues in the design of UAV are the design of thrust system and determination of the endurance of the UAV. Although propeller selection is very important for the thrust system design, battery selection has the utmost importance for the determination of UAV endurance. In this study, the calculations of maximum acceleration and endurance required by ZANKA-II during the flight are considered simultaneously. For this purpose, a model based on the ABC algorithm is proposed for the morphing UAV design, aiming to achieve the maximum acceleration and endurance. In the proposed model, the propeller diameter, propeller pitch and battery values used in morphing UAV's power system design are selected as the input parameters; maximum acceleration and endurance are selected as the output parameters. To obtain the maximum acceleration and endurance, the optimum input parameters are determined through the ABC algorithm-based model.

Findings

Considerable improvements on maximum acceleration and endurance of morphing UAV with ABC algorithm-based model are obtained.

Research limitations/implications

The endurance and acceleration due to the thrust are two separate parameters that are not normally proportional to each other. In this study, optimization of UAV’s endurance and acceleration is considered with equal importance.

Practical implications

Using artificial intelligence techniques causes fast and simple optimization for determination of UAV’s endurance and acceleration with equal importance. In the simulation studies with ABC algorithm, satisfactory results are obtained.

Social implications

The results of the study have showed that the proposed approach could be an alternative method for UAV designers.

Originality/value

Providing a new and efficient method saves time and reduces cost in calculations of maximum acceleration and endurance of the UAV.
Exploring sustainable competitive advantage of multispecialty hospitals in dynamic environment
Authors: Singh Harbir , Dey Ajoy Kumar , Sahay Arunaditya
Published: March 2020

Purpose

A multispecialty hospital possesses sustainable competitive advantage if it continuously improves performance, repeatedly delivers quality service and unique value to the patients and the sources of competitive advantage are valuable, rare, inimitable, non-substitutable or causally ambiguous. The term sustainable competitive advantage is vague and ambiguous and the environment in which hospitals operate is dynamic, turbulent and disruptive. Therefore, sources of competitive advantage must change and evolve with time. This paper aims to explore the themes of competitive advantage in a dynamic environment for multispecialty hospitals in India by studying data from secondary sources for five hospitals.

Design/methodology/approach

The findings of the case study were based on the analysis of secondary data that are extracted from the official websites of the hospitals, with the grounded theory approach.

Findings

Five identified themes are as follows: changing and adapting; clinical excellence; creating unique value; managing unpredictable circumstances and patient-centric approach. All the themes supported hospital performance, service and value delivered to patients and therefore may help in building a competitive advantage of the hospital. However, sustainability factors were inconsistent across the themes.

Practical implications

The CXOs and CMOs of hospitals can review the themes periodically and re-align the business strategies to build a sustainable competitive advantage.

Originality/value

The findings of the study uncovered the criticality of re-alignment of resources deployed in the unpredictable and ever-changing environment in which hospitals thrive to build sustainable competitive advantage.
A framework for accelerated optimization of antennas using design database and initial parameter set estimation
Authors: Koziel Slawomir , Bekasiewicz Adrian
Published: March 2020

Purpose

The purpose of this paper is to exploit a database of pre-existing designs to accelerate parametric optimization of antenna structures is investigated.

Design/methodology/approach

The usefulness of pre-existing designs for rapid design of antennas is investigated. The proposed approach exploits the database existing antenna base designs to determine a good starting point for structure optimization and its response sensitivities. The considered method is suitable for handling computationally expensive models, which are evaluated using full-wave electromagnetic (EM) simulations. Numerical case studies are provided demonstrating the feasibility of the framework for the design of real-world structures.

Findings

The use of pre-existing designs enables rapid identification of a good starting point for antenna optimization and speeds-up estimation of the structure response sensitivities. The base designs can be arranged into subsets (simplexes) in the objective space and used to represent the target vector, i.e. the starting point for structure design. The base closest base point w.r.t. the initial design can be used to initialize Jacobian for local optimization. Moreover, local optimization costs can be reduced through the use of Broyden formula for Jacobian updates in consecutive iterations.

Research limitations/implications

The study investigates the possibility of reusing pre-existing designs for the acceleration of antenna optimization. The proposed technique enables the identification of a good starting point and reduces the number of expensive EM simulations required to obtain the final design.

Originality/value

The proposed design framework proved to be useful for the identification of good initial design and rapid optimization of modern antennas. Identification of the starting point for the design of such structures is extremely challenging when using conventional methods involving parametric studies or repetitive local optimizations. The presented methodology proved to be a useful design and geometry scaling tool when previously obtained designs are available for the same antenna structure.
Improved buried pipe element method for temperature-field calculation of mass concrete with cooling pipes
Authors: Zhu Zhenyang , Liu Yi , Fan Zhe , Qiang Sheng , Xie Zhiqiang , Chen Weimin , Wu Congcong
Published: March 2020

Purpose

The buried pipe element method can be used to calculate the temperature of mass concrete through highly efficient computing. However, in this method, temperatures along cooling pipes and the convection coefficient of the cooling pipe boundary should be improved to achieve higher accuracy. Thus, there is a need to propose a method for improvement.

Design/methodology/approach

According to the principle of heat balance and the temperature gradient characteristics of concrete around cooling pipes, a method to calculate the water temperature along cooling pipes using the buried pipe element method is proposed in this study. By comparing the results of a discrete algorithm and the buried pipe element method, it was discovered that the convection coefficient of the cooling pipe boundary for the buried pipe element method is only related to the thermal conductivity of concrete; therefore, it can be calculated by inverse analysis.

Findings

The results show that the buried pipe element method can achieve the same accuracy as the discrete method and simulate the temperature field of mass concrete with cooling pipes efficiently and accurately.

Originality/value

This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.
Numerical analysis of the shear strength of circular reinforced concrete columns subjected to cyclic lateral loads using linear genetic programming
Authors: Rezvani Sharif Mostafa , Sadri Tabaei Zavareh Seyed Mohammad Reza
Published: March 2020

Purpose

The shear strength of reinforced concrete (RC) columns under cyclic lateral loading is a crucial concern, particularly, in the seismic design of RC structures. Considering the costly procedure of testing methods for measuring the real value of the shear strength factor and the existence of several parameters impacting the system behavior, numerical modeling techniques have been very much appreciated by engineers and researchers. This study aims to propose a new model for estimation of the shear strength of cyclically loaded circular RC columns through a robust computational intelligence approach, namely, linear genetic programming (LGP).

Design/methodology/approach

LGP is a data-driven self-adaptive algorithm recently used for classification, pattern recognition and numerical modeling of engineering problems. A reliable database consisting of 64 experimental data is collected for the development of shear strength LGP models here. The obtained models are evaluated from both engineering and accuracy perspectives by means of several indicators and supplementary studies and the optimal model is presented for further purposes. Additionally, the capability of LGP is examined to be used as an alternative approach for the numerical analysis of engineering problems.

Findings

A new predictive model is proposed for the estimation of the shear strength of cyclically loaded circular RC columns using the LGP approach. To demonstrate the capability of the proposed model, the analysis results are compared to those obtained by some well-known models recommended in the existing literature. The results confirm the potential of the LGP approach for numerical analysis of engineering problems in addition to the fact that the obtained LGP model outperforms existing models in estimation and predictability.

Originality/value

This paper mainly represents the capability of the LGP approach as a robust alternative approach among existing analytical and numerical methods for modeling and analysis of relevant engineering approximation and estimation problems. The authors are confident that the shear strength model proposed can be used for design and pre-design aims. The authors also declare that they have no conflict of interest.
Effects of window proximity on perceptions of employees in the call center offices
Authors: Yildirim Kemal , Ozkan Aysen , Gunes Elif , Mestan Ahmet
Published: March 2020

Purpose

The purpose of this study is to determine the effects of window proximity on perceptions of employees in the call center offices.

Design/methodology/approach

A semantic differential scale composed of nine bipolar adjectives, four of which dealt with “planning,” three of “privacy,” while the rest measured “lighting” was applied for evaluation. In total, 92 employees at the TEPE Call Center in the Bilkent District, Ankara, Turkey participated in the research.

Findings

The results showed that window proximity directly affected the call center employees’ perceptions. In addition, a positive approach was even less affected when the location of the workstation was more at the inner part of the workspace. On the contrary, workstations in front of the window were evaluated more positively, presumably because the employees were happy at feeling roomy and by giving them a higher level of privacy, while also minimizing distractions and interruptions. It was also found that call center employees with secondary education responded more positively than higher educated employees.

Research limitations/implications

This study was limited to examining the effects of window proximity in a call center on employees’ perceptions of an open-plan office. The study supports the results of planning, privacy and lighting, as well as the study on physical environmental factors, such as design, ambient and social, which are thought to be realized in the future.

Originality/value

This study presents suggestions that would be useful for increasing the working and solution-focused perceptual performance values in call center environments from the new generation of work areas. They should be appropriate for the psychological and physical needs of employees in twenty-first-century communication environments, especially in spatial environments and for the suitability of the technological equipment used.
Grey modeling for thermal spray processing parameter analysis
Authors: Liu Meimei , Zhang Yicha , Dong Wenjie , Yu Zexin , Liu Sifeng , Gomes Samuel , Liao Hanlin , Deng Sihao
Published: March 2020

Purpose

This paper presents the application of grey modeling for thermal spray processing parameter analysis in less data environment.

Design/methodology/approach

Based on processing knowledge, key processing parameters of thermal spray process are analyzed and preselected. Then, linear and non-linear grey modeling models are integrated to mine the relationships between different processing parameters.

Findings

Model A reveals the linear correlation between the HVOF process parameters and the characterization of particle in-flight with average relative errors of 9.230 percent and 5.483 percent for velocity and temperature.

Research limitations/implications

The prediction accuracies of coatings properties vary, which means that there exists more complex non-linear relationship between the identified input parameters and coating results, or more unexpected factors (e.g. factors from material side) should be further investigated.

Practical implications

According to the modeling case in this paper, method has potential to deal with other diverse modeling problems in different industrial applications where challenge to collecting large quantity of data sets exists.

Originality/value

It is the first time to apply grey modeling for thermal spray processing where complicated relationships among processing parameters exist. The modeling results show reasonable results to experiment and existing processing knowledge.
Numerical investigation on activation energy of chemically reactive heat transfer unsteady flow with multiple slips
Authors: Majeed Aaqib , Amin Noorul , Zeeshan A. , Ellahi R. , Sait Sadiq M. , Vafai K.
Published: March 2020

Purpose

The purpose of this study is to examine the impact of activation energy with binary chemical reaction for unsteady flow on permeable stretching surface.

Design/methodology/approach

The simultaneous effects of multiple slip and magneto-hydrodynamic effects at the boundary are taken into account. The thermal buoyancy parameter and thermal radiation are included in both energy and momentum equations, while expression of activation energy is considered in concentration equation. Three-stage Lobatto IIIa finite difference collocation technique with bvp4c MATLAB package is used to obtained numerical results.

Findings

The influence of key elements (Schmidt number, buoyancy force ratio factor, factor of radiation, magnetic element, unsteadiness factor, suction/injection parameter, Prandtl number, activation energy, chemical reaction rate parameter, heat source and sink parameters, velocity, thermal and concentration slips, porosity parameter and temperature difference parameter) on velocity, temperature and concentration profiles are illustrated pictorially. A detailed discussion is presented to see how the graphical aspects justify the physical prospect.

Originality/value

In the best of author’s knowledge, this work is yet not available in existing literature.
Collective decision-making for developing emergency management capabilities
Authors: Oh Namkyung
Published: March 2020

Purpose

The purpose of this study is to explore the applicability of analytic hierarchy process (AHP) to collective decision-making of local and state disaster managers for their efficient and effective allocation of limited financial resources.

Design/methodology/approach

For the implementation of AHP, this study conducted an AHP survey with state and local disaster managers in post-Katrina Louisiana, the USA.

Findings

The AHP analysis disclosed a preference gap between local and state managers. It also identified frequent interaction with partners, leadership and communication, as the most critical capabilities to develop for effective emergency management.

Research limitations/implications

This study discussed the value of consistent and careful management of the collaborative relationship. This study is context-specific in disaster type (Hurricane) and locality (Louisiana). Other AHP studies or similar multi-criteria decision-making models should be implemented in different contexts.

Originality/value

Even with clear advantages of collective decision-making in the emergency management field, a model for collective decision-making has been rare. This study explored the applicability of AHP to the collective decision-making for the efficient and effective allocation of limited financial resources.
National study of emergency medical services core competencies in Saudi Arabia
Authors: AlShammari Talal , Jennings Paul , Williams Brett
Published: March 2020

Purpose

Emergency medical services (EMS) educational standards in Saudi Arabia have developed at an unprecedented rate, and the rapid pace of development has resulted in a considerable disparity of educational approaches. Therefore, an empirically based core competency framework should be developed. The aim was to utilize exploratory factor analysis (EFA) in the reduction and generation of a theoretical Saudi competency model.

Design/methodology/approach

A purposive sample was utilized in a national quantitative cross-sectional study design of Saudi Red Crescent Authority (SRCA) healthcare workers. The instrument comprised 41 core competency items rated on a Likert scale. EFA alpha factoring with oblique promax rotation was applied to the 41 items.

Findings

A total of 450 EMS healthcare providers participated in the study, of whom 422 (93.8 per cent) were male and 28 (6.2 per cent) female. Of the participants, 230 (60 per cent) were aged 29–39 years and 244 (54.2 per cent) had 5–9 years of experience. An EFA of instrument items generated five factors: professionalism, preparedness, communication, clinical and personal with an eigenvalue > 1, representing 67.5 per cent of total variance. Only variables that had a loading value >0.40 were utilized in the factor solution.

Originality/value

The EFA model Saudi ParamEdic Competency Scale (SPECS) has been identified, with 27 core competency items and five overarching factors. The model has considerable similarities to other medical competency frameworks. However, some aspects are specifically unique to the Saudi EMS context. The SPECS model provides an academic blueprint that can be used by paramedic educational programs to ensure empirical alignment with the needs of the industry and community.
Technology forecast: a case study in Daiken company
Authors: Sartori Rodrigo Vinicius , Reis Dalcio Roberto dos , Bronzeri Marcia , Silva Adriana Queiroz
Published: March 2020

Purpose

This paper aims to describe how the technology forecast process occurs at a technology-based company named Daiken, a Brazilian electronics industry, located in the state of Parana. The study helps to clarify the context that tech-companies in Brazil face when trying to forecast new technologies.

Design/methodology/approach

The paper opted for a case study, in a qualitative and descriptive approach. Primary data were collected through a semi-structured interview and non-participant observation. Secondary data were generated through documentary research.

Findings

Outcomes indicate that, for the studied case, technology forecast practices are adopted in an informal and unsystematic way, best aligned to the nature of competitive intelligence.

Research limitations/implications

Because of the chosen research approach, the results may lack generalizability. Therefore, researchers are encouraged to test the propositions further.

Practical implications

The paper includes implications for the adjustment of technology forecast tools to the reality seen in emergent nations like Brazil.

Originality/value

This paper fulfills an identified need to study how to conduct the technology forecast processes in small and mid-tech-companies in Brazil.
Effects of welding speeds on the microstructural and mechanical properties of AZ91D Mg alloy by friction stir welding
Authors: Kadigithala Nagabhushan Kumar , C Vanitha
Published: March 2020

Purpose

The main purpose of the present work is to evaluate, the microstructural and mechanical properties of friction stir welded plates of AZ91D magnesium alloy with 3 mm thickness, and to determine the optimum range of welding conditions.

Design/methodology/approach

Microstructure and fractographic studies were carried out using scanning electron microscopy (SEM). Vickers micro hardness test was performed to evaluate the hardness profile in the region of the weld area. The phases in the material were confirmed by X-Ray diffraction (XRD) analysis. Transverse tensile tests were conducted using universal testing machine (UTM) to examine the joint strength of the weldments at different parameters.

Findings

Metallographic studies revealed that each zone shown different lineaments depending on the mechanical and thermal conditions. Significant improvement in the hardness was observed between the base material and weldments. Transverse tensile test results of weldments had shown almost similar strength that of base material regardless of welding speed. Fractographic examination indicated that the welded specimens failed due to brittle mode fracture. Through these studies it was confirmed that friction stir welding (FSW) can be used for the welding of AZ91D magnesium alloy.

Research limitations/implications

In the present study, the welding speed varied from 25 mm/min to 75 mm/min, tilt angle varied from 1.5° to 2.5° and constant rotational speed of 500 rpm.

Practical implications

Magnesium and aluminum based alloys which are having high strength and low density, used in automotive and aerospace applications can be successfully joined using FSW technique. The fusion welding defects can be eliminated by adopting this technique.

Originality/value

Limited work had been carried out on the FSW of magnesium based alloys over aluminum based alloys. Furthermore, this paper analyses the influence of welding parameters over the microstructural and mechanical properties.