bluuebunny/crossref_metadata_2025 huggingface dataset:
How do primary healthcare workers in low-income and middle-income countries obtain information during consultations to aid safe prescribing? A systematic review protocol
Authors: Smith Chris , van Velthoven Michelle Helena , Pakenham-Walsh Neil
Published: January 2019

Introduction

There is a wide variety in prescribing by primary healthcare workers in low-income and middle-income countries. While there is much information available, both online and offline, there is variation in quality and relevance to different settings. Acting on incorrect or out-of-date information can lead to inappropriate prescribing and impact on patient safety. The aim of this review is to systematically review the evidence on how primary healthcare workers obtain information during consultations to prescribe safely and appropriately.

Methods and analysis

We will identify relevant articles by searching electronic databases: Medline (Ovid), EMBASE (Ovid), Cochrane Central Register of Controlled Trials, CABI Global Health (Ovid), WHO global health library, POPLINE, Africa-Wide Information (Ebsco), Library, Information Science & Technology Abstracts (Ebsco), ClinicalTrials.gov and WHO International Clinical Trials Registry Platform. Also, the Health Information For All network will be consulted and evidence databases (TRIP database, Epistemonikos, PDQ Evidence) will be searched. We will hand-search reference lists, run citation searches of included studies and email authors of identified papers. Observational and intervention studies involving primary healthcare workers in low-income and middle-income countries who prescribe and/or dispense medication will be included. The primary outcome is the proportion of healthcare workers obtaining information relevant to consultations from different sources. Secondary outcomes are the change in healthcare provider and patient knowledge or behaviour, adverse outcomes and use of resources. We will exclude studies focusing on secondary care. We anticipate a limited scope for meta-analysis and will provide a narrative overview of findings and tabular summaries of extracted data.

Ethics and dissemination

No ethics approval is required. Findings will be disseminated through the Healthcare Information For All network.

PROSPERO registration number

CRD42018091088.
Does price regulation affect atorvastatin sales in India? An impact assessment through interrupted time series analysis
Authors: Selvaraj Sakthivel , Farooqui Habib Hasan , Mehta Aashna
Published: January 2019

Objective

The objective of this study was to examine the impact of medicines price regulation (Drug Price Control Order, 2013) on the market share of atorvastatin in the Indian retail market for statins.

Setting

All Indian states, January 2012 to December 2015.

Design

Quasi-experimental—interrupted time series analysis.

Data

Pharmaceutical sales audit data set from IMS Health (now IQVIA) for the 48-month period from January 2012 to December 2015.

Outcome measure

Share of atorvastatin (in percentage) in the Indian market for statins in terms of sales volumes.

Results

We observed that the price regulation notification (Drug Price Control Orders, 2013) was associated with 0.12% (p<0.001; 95% CI 0.06 to 0.18) increase in the trend of the average monthly market share of atorvastatin (5 mg and 10 mg). After 31 months of price ceilings notification, the average market share of atorvastatin was 3.41% higher than would have been expected had the price ceilings not been notified. In sensitivity analysis, with a control, our findings remain robust, we observed a 0.16% (p<0.001; 95% CI 0.08 to 0.24) rise in the trend of average monthly market share of atorvastatin (5 mg and 10 mg) as compared with the change in the control.

Conclusions

Price control as a public intervention did improve the relative sales of atorvastatin in the statin market in India.
Efficacy of biological drugs in short-duration versus long-duration inflammatory bowel disease: a protocol for a systematic review and an individual-patient level meta-analysis of randomised controlled trials
Authors: Ben-Horin Shomron , Zhao Yue , Guo Jing , Mao Ren , Novack Lena , Sergienko Ruslan , Zhang Jian , Kobayashi Taku , Hibi Toshifumi , Chowers Yehuda , Colombel Jean Frederic , Peyrin-Biroulet Laurent , Kaplan Gilaad , Chen Min-hu
Published: January 2019

Introduction

Crohn’s disease (CD) and ulcerative colitis (UC) are remitting–relapsing inflammatory diseases often culminating in disease complications and/or need for surgery. Biologic monoclonal antibody drugs (‘Biologics’) are efficacious for both diseases, but there are no systematic assessments of their efficacy if administered early after disease onset (‘top-down’ strategy) vis-à-vis later in the course of disease (‘step-up’ approach).

Methods and analysis

Electronic databases (MEDLINE, EMBASE/EMBASE classic Cochrane CENTRAL register of controlled trials, the Cochrane IBD Group Specialised Trials Register and Clinicaltrials.gov registry) will be searched to identify all randomised placebo-controlled clinical trials of food and drug administration (FDA)-approved biologics for CD and UC (by March 2016). Two independent reviewers will screen identified papers, extract data and assess the risk of bias according to the Cochrane Handbook for Systematic Reviews of Interventions. Individual-patient-level data (IPD) will be extracted from the identified trials through data-sharing platforms for pharmaceutical companies’ sponsored trials and by contacting principal investigators of independent investigator-initiated trials. We will analyse induction of remission in patients with early-disease (<18 months since disease onset) versus patients with longer disease duration, using a generalised linear mixed effect model and by a two-stage approach using coefficient for the treatment-by-subgroup interaction within each trial. We will perform receiver operator curve analysis of optimal disease duration for response. Analyses will be separate for CD and UC. This first-of-its-kind meta-analysis at IPD level of interaction of disease duration with the response to biologics in UC and CD may elucidate the impact of early initiation of biologics, which is of paramount importance for clinical practice and management strategies of inflammatory bowel disease.

Ethics and dissemination

This meta-analysis was approved by the Ethics Committee of the First Affiliated Hospital of Sun Yat-sen University. Findings will be published in peer-reviewed journal and disseminated via scientific meetings and links with organisations.

PROSPERO registration number

CRD42018041961.
Impact of surgical site infection (SSI) following gynaecological cancer surgery in the UK: a trainee-led multicentre audit and service evaluation
Authors: O’Donnell Rachel L , Angelopoulos Georgios , Beirne James P , Biliatis Ioannis , Bolton Helen , Bradbury Melissa , Craig Elaine , Gajjar Ketan , Mackintosh Michelle L , MacNab Wendy , Madhuri Thumuluru Kavitha , McComiskey Mark , Myriokefalitaki Eva , Newton Claire L , Ratnavelu Nithya , Taylor Sian E , Thangavelu Amudha , Rhodes Sarah A , Crosbie Emma J , Edmondson Richard J , Wan Yee-Loi Louise
Published: January 2019

Objectives

Surgical site infection (SSI) complicates 5% of all surgical procedures in the UK and is a major cause of postoperative morbidity and a substantial drain on healthcare resources. Little is known about the incidence of SSI and its consequences in women undergoing surgery for gynaecological cancer. Our aim was to perform the first national audit of SSI following gynaecological cancer surgery through the establishment of a UK-wide trainee-led research network.

Design and setting

In a prospective audit, we collected data from all women undergoing laparotomy for suspected gynaecological cancer at 12 specialist oncology centres in the UK during an 8-week period in 2015. Clinicopathological data were collected, and wound complications and their sequelae were recorded during the 30 days following surgery.

Results

In total, 339 women underwent laparotomy for suspected gynaecological cancer during the study period. A clinical diagnosis of SSI was made in 54 (16%) women. 33% (18/54) of women with SSI had prolonged hospital stays, and 11/37 (29%) had their adjuvant treatment delayed or cancelled. Multivariate analysis found body mass index (BMI) was the strongest risk factor for SSI (OR 1.08[95% CI 1.03 to 1.14] per 1 kg/m2increase in BMI [p=0.001]). Wound drains (OR 2.92[95% CI 1.41 to 6.04], p=0.004) and staple closure (OR 3.13[95% CI 1.50 to 6.56], p=0.002) were also associated with increased risk of SSI.

Conclusions

SSI is common in women undergoing surgery for gynaecological cancer leading to delays in discharge and adjuvant treatment. Resultant delays in adjuvant treatment may impact cancer-specific survival rates. Modifiable factors, such as choice of wound closure material, offer opportunities for reducing SSI and reducing morbidity in these women. There is a clear need for new trials in SSI prevention in this patient group; our trainee-led initiative provides a platform for their successful completion.
Are predominantly western standards and expectations of informed consent in surgery applicable to all? A qualitative study in a tertiary care hospital in Sri Lanka
Authors: Samaranayake Udagedara Mudiyanselage Jayami Esha , Mathangasinghe Yasith , Banagala Anura Sarath Kumara
Published: January 2019

Objective

To identify the different perceptions on informed surgical consent in a group of Sri Lankan patients.

Methods

A qualitative study was conducted in a single surgical unit at a tertiary care hospital from January to May 2018. The protocol conformed to the Declaration of Helsinki. Patients undergoing elective major surgeries were recruited using initial purposive and later theoretical sampling. In-depth interviews were conducted in their native language based on the grounded theory. Initial codes were generated after analysing the transcripts. Constant comparative method was employed during intermediate and advanced coding. Data collection and analyses were conducted simultaneously, until the saturation of the themes. Finally, advanced coding was used for theoretical integrations.

Results

Thirty patients (male:female=12:18) were assessed. The mean age was 41±9 years. Sinhalese predominated (50.0%, n=15). Majority underwent thyroidectomy (36.7%, n=11). The generated theory categorises the process of obtaining informed consent in four phases: initial interaction phase, reasoning phase, convincing phase and decision-making phase. Giving consent for surgery was a dependent role between patient, family members and the surgeon, as opposed to an individual decision by the patient. Some patients abstained from asking questions from doctors since doctors were ‘busy’, ‘short-tempered’ or ‘stressed out’. Some found nurses to be more approachable than doctors. Patients admitted that having a bystander while obtaining consent would relieve their stress. They needed doctors to emphasise more on postoperative lifestyle changes and preprocedure counselling at the clinic level. To educate patients about their procedure, some suggested leaflets or booklets to be distributed at the clinic before ward admission. The majority disliked watching educational videos because they were ‘scared’ to look at surgical dissections and blood.

Conclusion

The informed consent process should include key elements that are non-culture specific along with elements or practices that consider the cultural norms of the society.
Prevalence of frailty in rural community-dwelling older adults in Kegalle district of Sri Lanka: a population-based cross-sectional study
Authors: Siriwardhana Dhammika Deepani , Weerasinghe Manuj Chrishantha , Rait Greta , Falcaro Milena , Scholes Shaun , Walters Kate R
Published: January 2019

Objective

Our main objective was to describe the prevalence and associated sociodemographic factors of frailty and pre-frailty in rural community-dwelling older adults in Kegalle district of Sri Lanka.

Design

Community-based cross-sectional study.

Setting

The study was conducted in rural areas of Kegalle district in Sri Lanka.

Participants

A total of 746 community-dwelling older adults aged ≥60 years were included in the study.

Results

The prevalence of frailty and pre-frailty in rural Kegalle district was 15.2% (95% CI 12.3% to 18.6%) and 48.5% (95% CI 43.8% to 53.2%), respectively. We found a strong association between age and both frailty and pre-frailty. There were strong associations between longest-held occupation and frailty and education level and pre-frailty.

Conclusions

The prevalence of frailty in this rural Sri Lankan older population was high compared with high-income and upper middle-income countries. The profile of health and social care services in Sri Lanka needs to address frailty and its consequences.
Prevention of child mental health problems in Southeastern Europe: a multicentre sequential study to adapt, optimise and test the parenting programme ‘Parenting for Lifelong Health for Young Children’, protocol for stage 1, the feasibility study
Authors: Frantz Inga , Foran Heather M , Lachman Jamie M , Jansen Elena , Hutchings Judy , Băban Adriana , Fang Xiangming , Gardner Frances , Lesco Galina , Raleva Marija , Ward Catherine L , Williams Margiad Elen , Heinrichs Nina
Published: January 2019

Introduction

Families in low-income and middle-income countries (LMICs) face multiple challenges (eg, poverty and adverse childhood experiences) that increase the risk for child mental health problems, while the context may provide them with few resources. Existing prevention-oriented parenting programmes have been shown to be effective in reducing child behaviour problems and associated risk factors. This project has the overall goal of adapting, implementing and testing a parenting intervention in three Southeastern European LMIC and uses the Multiphase Optimisation Strategy and dimensions of the Reach, Effectiveness, Adoption, Implementation and Maintenance framework. It is implemented over three phases: (1) preparation, (2) optimisation and (3) evaluation. The preparation phase, the subject of this paper, involves the adaptation and feasibility piloting of the parenting programme.

Methods and analysis

This protocol describes the assessment of an evidence-informed indicated prevention programme for families with children aged 2–9 years (Parenting for Lifelong Health for Young Children) for implementation in FYR of Macedonia, Republic of Moldova and Romania. In this phase, officials, experts, parents and practitioners are interviewed to explore their views of suitability and needs for further adaptation. In addition, a small pre–post pilot study will test the feasibility of the programme and its implementation as well as the evaluation measures in the three countries with 40 families per country site (n=120). Quantitative data analysis will comprise a psychometric analysis of measures, testing pre–post differences using ANCOVA, χ2tests and regression analysis. For qualitative data analysis, a thematic approach within an experiential framework will be applied.

Ethics and dissemination

The ethics review board of the Alpen-Adria University Klagenfurt and ethical review boards in the three LMIC sites have approved the study.

Trial registration number

NCT03552250.
Parallel and serial mediation analysis between pain, anxiety, depression, fatigue and nausea, vomiting and retching within a randomised controlled trial in patients with breast and prostate cancer
Authors: Charalambous Andreas , Giannakopoulou Margarita , Bozas Evaggelos , Paikousis Lefkios
Published: January 2019

Objective

Cancer treatment is a particularly stressful period for the patient. The reasons vary and include fear of treatment outcome as well as treatment induced side effects. The patient frequently experiences simultaneously various side effects resulting in a diminishing of the patient’s health-related quality of life (HRQoL). The study provides evidence on the co-occurrence and inter-relations between pain, anxiety, depression and fatigue in patients with breast and prostate cancer.

Design

This paper presents a secondary analysis of the data from a randomised control trial designed to test the effectiveness of guided imagery and progressive muscle relaxation on pain, fatigue, anxiety and depression. Non-parametric bootstrapping analyses were used to test the mediational model of anxiety, fatigue and depression as parallel mediators of the relationship between pain and HRQoL.

Setting

The study was undertaken at the home setting.

Participants

In total 208 patients were included in the study (assigned equally in two groups), referred at the outpatient clinics of the three participating cancer care centres.

Results

The three mediators fully mediate the relationship between pain and HRQoL indirect effect (IEoverall=−0.3839, 95% CI: lower limit (LL)=−0.5073 to upper limit (UL)=−0.2825) indicating that patients with increased pain are likely to have higher levels of anxiety, fatigue and depression. Gender significantly moderated the mediational effect of Fatigue Index of Moderated Mediation (IMM=−0.2867 SE=0.1526, LL=−0.6127, UL=−0.0226) but did not moderate mediational effect of anxiety (IMM=−0.0709, SE=0.1414, LL=−0.3459, UL=+0.2089). The results show that the three mediators in a serial causal order fully mediate the relationship between pain and HRQoL (IEoverall=−0.384, 95% CI: LL=−0.51 to UL=−0.284) and the ratio of the overall indirect effect to the total effect is 0.8315 (95% CI: LL=0.5683 to UL=1.1718).

Conclusion

This work provides evidence that targeting fatigue, anxiety and depression may have a meaningful effect on pain as a related symptom and potentially have a positive impact on HRQoL of patients with breast and prostate cancer

Trial registration number

NCT01275872; Post-results.
Home self-administration of intravenous antibiotics as part of an outpatient parenteral antibiotic therapy service: a qualitative study of the perspectives of patients who do not self-administer
Authors: Tonna Antonella , Anthony Geraldine , Tonna Ivan , Paudyal Vibhu , Forbes-McKay Katrina , Laing Rob , Mackenzie Alexander , Falconer Sharon , McCartney Gillian , Stewart Derek
Published: January 2019

Objectives

This study aimed to use a theoretical approach to understand the determinants of behaviour in patients not home self-administering intravenous antibiotics.

Setting

Outpatient care: included patients were attending an outpatient clinic for intravenous antibiotic administration in the northeast of Scotland.

Participants

Patients were included if they had received more than 7 days of intravenous antibiotics and were aged 16 years and over. Twenty potential participants were approached, and all agreed to be interviewed. 13 were male with a mean age of 54 years (SD +17.6).

Outcomes

Key behavioural determinants that influenced patients’ behaviours relating to self-administration of intravenous antibiotics.

Design

Qualitative, semistructured in-depth interviews were undertaken with a purposive sample of patients. An interview schedule, underpinned by the Theoretical Domains Framework (TDF), was developed, reviewed for credibility and piloted. Interviews were audio-recorded and transcribed verbatim. Data were analysed thematically using the TDF as the coding framework.

Results

The key behavioural determinants emerging as encouraging patients to self-administer intravenous antibiotics were the perceptions of being sufficiently knowledgeable, skilful and competent and that self-administration afforded the potential to work while administering treatment. The key determinants that impacted their decision not to self-administer were lack of knowledge of available options, a perception that hospital staff are better trained and anxieties of potential complications.

Conclusion

Though patients are appreciative of the skills and knowledge of hospital staff, there is also a willingness among patients to home self-administer antibiotics. However, the main barrier emerges to be a perceived lack of knowledge of ways of doing this at home. To overcome this, a number of interventions are suggested based on evidence-based behavioural change techniques.
Do golf fans walk the talk? Follow-up of spectators’ beliefs and self-reported physical activity 3 months after they attended a professional golf tournament in the UK
Authors: Murray Andrew D , Hawkes Roger A , Kelly Paul , Grant Liz , Mutrie Nanette
Published: January 2019

Background

Previous research of spectators at professional golf tournaments has highlighted that obtaining exercise/physical activity (PA) can be a motivator to attend, and that spectators can engage in health-enhancing PA while at the event. We assessed whether attending a golf event and receiving an intervention improve knowledge and change attitudes related to physical activity, and self-reported physical activity 3 months later.

Methods

Follow-up observational study. Spectators at a European Tour Golf event were given a leaflet about physical activity and health. Three months after that event, we emailed a questionnaire to all 326 spectators who had participated in the original study and provided us their contact details.

Results

135 spectators (41.4%) completed the questionnaire. Among responders, 68.0% ‘agreed/strongly agreed’ that their knowledge relating to PA had increased, 65.1% agreed/strongly agreed that receiving this information at the event made them consider increasing physical activity in daily life and 40.4% reported that they had increased their physical activity during the 3 months after the golf tournament.

Principal findings/conclusions

Golf spectators may contemplate/prepare to increase PA in daily life while a smaller number self-report an increase in PA during the 3 months post intervention at a golf tournament. Spectators’ preferred method for receiving information about ‘active spectating’ is via a big screen. These findings are presented with caution, as respondents may not be representative of all golf spectators.
Randomized controlled trial of a simplified adductor canal block performed for analgesia following total knee arthroplasty
Authors: Swenson Jeffrey D , Pollard Jacob E , Peters Christopher L , Anderson Mike B , Pace Nathan L
Published: January 2019

Background and objectives

The objective of the study was to determine if injection of local anesthetic into the vastus medialis and sartorius muscles adjacent to the adductor canal produces sensory changes comparable with adductor canal block (ACB). This could result in a technically easier and potentially safer alternative to ACB.

Methods

In this randomized controlled trial, patients received either ACB (n=20) or a simplified adductor canal (SAC) block performed using a new fenestrated nerve block needle (n=20). The time to perform each block as well as the number of attempts to position the needle were evaluated. A non-inferiority test was used to compare pain scores and opioid requirements for the ACB and the SAC block.

Results

The SAC block was performed more rapidly, with fewer needle passes, and had a higher success rate than the ACB. Three block failures and two vessel punctures were observed in the ACB group, while none of these events occurred in SAC block patients. Analgesia and opioid consumption for patients treated with the SAC block were not inferior to ACB.

Conclusion

The SAC block is technically easier to perform and potentially safer than ACB. This procedure can be performed using easily visible ultrasound landmarks and has the potential for use among a wide range of healthcare providers.

Trial registration number

NCT02786888.
The focused assessment with sonography in trauma (FAST) in hypotensive injured patients frequently fails to identify the need for laparotomy: a multi-institutional pragmatic study
Authors: Rowell Susan E , Barbosa Ronald R , Holcomb John B , Fox Erin E , Barton Cassie A , Schreiber Martin A
Published: January 2019

Background

The ability of focused assessment with sonography for trauma (FAST) to detect clinically significant hemorrhage in hypotensive injured patients remains unclear. We sought to describe the sensitivity and specificity of FAST using findings at laparotomy as the confirmatory test.

Methods

Patients from the Prospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study that had a systolic blood pressure < 90mm Hg and underwent FAST were analysed. Results were compared with findings at laparotomy. A therapeutic laparotomy (T-LAP) was defined as an abdominal operation within 6 hours in which a definitive procedure was performed. The sensitivity and specificity of FAST were calculated.

Results

The cohort included 317 patients that underwent FAST (108 positive, 209 negative). T-LAP was performed in 69% (n=75) of FAST(+) patients and 22% (n=48) of FAST(−) patients. FAST had a sensitivity of 62% and specificity of 83%.

Conclusions

In our multicenter cohort, 22% of FAST(−) patients underwent T-LAP within 6 hours of admission. In hypotensive patients with a negative FAST, clinicians should still maintain a high index of suspicion for significant abdominal hemorrhage.

Level of evidence

Level IV.
Effect of the degree of decay on the electrical resistance of wood degraded by brown-rot fungi
Authors: Gao Shan , Yue Xiaoquan , Wang Lihai
Published: January 2019

There have been limited efforts to investigate the association between wood decay and electrical resistance; consequently, we have examined the change in the electrical resistance of wood progressively decayed by brown-rot fungi to elucidate the effect of the degree of decay. The rate of mass loss of wood was used as an indicator of the degree of fungal decay. The changes in the moisture content and ion concentrations were measured at various decay stages. The results showed a significant difference in the electrical resistances of sound wood and fungal-treated wood after 24 weeks. The electrical resistance significantly decreased with the exposure time. The degree of decay increased as the mass loss increased, resulting in the severe breakdown of cell walls and the accumulation of fungal mycelia. Empirical models related to the rate of mass loss and the percent decrease in the electrical resistance were established. The moisture content and cation concentrations increased to various degrees in decayed wood. This increase in the cation concentration was considered to play a dominant role in the decrease in the electrical resistance. The study results provide valuable information for developing an electrical resistance based method coupled with ion content measurements for incipient wood decay detection.
Elemental analysis of cultured pearls by PIXE
Authors: Sakakura Ikuko , Tsuchida Hidetsugu , Sasaki Yoshitaka , Hayashii Hisaki
Published: January 2019

Cultured pearls are formed in pearl sacs comprising epithelial cells transplanted into mother-of-pearl. The formation mechanism is complicated and is still not fully understood. Previous studies have shown that the pearl formation is influenced by aquaculture environment and physiological activity of shellfish. The elemental compositions of seawater and freshwater pearls are significantly different. In this work, we used the particle-induced X-ray emission (PIXE) technique to perform elemental analysis of six types of pearls: ordinary and blue Akoya pearls, black-, gold-, and white-lipped oyster pearls, and freshwater Biwako pearl. We investigate the influence of trace elements in aquaculture environments on formation of mother-of-pearl or color. The Mn/Sr or Fe/Sr ratio for the freshwater pearl was found to be significantly higher than that for the seawater pearl. Comparing the sweater pearls, the gold-lipped oyster pearl has high value of Mn/Sr ratio. The Fe/Sr and Cu/Sr ratios for two Akoya pearls harvested from the Sea of Japan are relatively high compared with black-, gold-, and white-lipped oyster pearls from the South Sea.
A comparison of two biholomorphic invariants
Authors: Mahajan Prachi , Verma Kaushal
Published: January 2019

The Fridman invariant, which is a biholomorphic invariant on Kobayashi hyperbolic manifolds, can be seen as the dual of the much studied squeezing function. We compare this pair of invariants by showing that they are both equally capable of determining the boundary geometry of a bounded domain if their boundary behavior is a priori known.
Nica–Toeplitz algebras associated with right-tensor C∗-precategories over right LCM semigroups
Authors: Kwaśniewski Bartosz K. , Larsen Nadia S.
Published: January 2019

We introduce and analyze the full [Formula: see text] and the reduced [Formula: see text] Nica–Toeplitz algebra associated to an ideal [Formula: see text] in a right-tensor [Formula: see text]-precategory [Formula: see text] over a right LCM semigroup [Formula: see text]. These [Formula: see text]-algebras unify cross-sectional [Formula: see text]-algebras associated to Fell bundles over discrete groups and Nica–Toeplitz [Formula: see text]-algebras associated to product systems. They also allow a study of Doplicher–Roberts versions of the latter. A new phenomenon is that when [Formula: see text] is not right cancellative then the canonical conditional expectation takes values outside the ambient algebra. Our main result is a uniqueness theorem that gives sufficient conditions for a representation of [Formula: see text] to generate a [Formula: see text]-algebra naturally lying between [Formula: see text] and [Formula: see text]. We also characterize the situation when [Formula: see text]. Unlike previous results for quasi-lattice monoids, [Formula: see text] is allowed to contain nontrivial invertible elements, and we accommodate this by identifying an assumption of aperiodicity of an action of the group of invertible elements in [Formula: see text]. One prominent condition for uniqueness is a geometric condition of Coburn’s type, exploited in the work of Fowler, Laca and Raeburn. Here we shed new light on the role of this condition by relating it to a [Formula: see text]-algebra associated to [Formula: see text] itself.
Two-dimensional numerical modeling of sediment transport in a dam reservoir to analyze the feasibility of a water intake
Authors: Charafi My. M.
Published: January 2019

The present work is related to the study of a water intake projected into a dam reservoir, located in northern Morocco. The object sought is to examine the natural conditions surrounding a water intake and their possible repercussions on its operation. Thus, a two-dimensional numerical model is developed to simulate the sediment transport in a reservoir dam. The developed model consists of hydrodynamic module based on the Saint–Venant equations and sediment transport module based on the mass-balance equation, where there are resolved by a MacCormack numerical scheme and upwind scheme, respectively. The analysis using the numerical model has made it possible to predict the shutdown periods of the drinking water production station with respect to the rate of suspended solids (SS) for extreme rainfall events.
A package for the computational analysis of complex biophysical signals
Authors: Guerrero J. A. , Macías-Díaz Jorge E.
Published: January 2019

Electromyograms are biomedical signals which are detected through electrodes. These signals represent measurements of the electric potentials associated to muscles contractions, and they are physically important in view that they provide information on the health of individuals. The computational modeling of electromyograms has been mainly carried out through general-purpose commercial software, which is typically provided with the purchase of computer equipment. In view of the well-known limitations inherent in the commercial software, a lot of research and efforts are devoted continuously to upgrade existing processing methods. However, as expected, these innovations take a considerable amount of time in order to be implemented in commercial software. In order to alleviate this situation, the package has been developed to provide a free and fully open-source package for both applied and theoretical researchers, which includes some fundamental tools to computationally process electromyograms. The purpose of the present paper is to provide an overview of the most important features of this package, and to supply codes and examples to illustrate its use.
A two-fluid model for gas-particle turbulent flows based on the probability density function approach
Authors: Wang Lu , Xu Jiangrong
Published: January 2019

According to experimental observations, laden particles in turbulence may attenuate or augment the carrier phase turbulence. But until now, there are no widely recognized models for estimating the so-called turbulence modulation phenomenon. In this paper, a novel two-fluid model is proposed based on the probability density function (PDF) approach. The Reynolds stress equation of the present model contains both production and dissipation terms due to the presence of particles, the turbulence modulation phenomenon can be well explained with the new model. To further explore the two-fluid model, a comparative study on PDF and Reynolds-averaged approaches is carried on, the differences and relations between the present model and the classical two-fluid Reynolds averaged Navier–Stokes (RANS) model are analyzed in the paper. Theoretical and numerical analysis indicates that the proposed model shows particular promise for predicting particle-laden turbulent flows.
EXPLAINING GAPS IN INFRASTRUCTURE INVESTMENT BY MUNICIPAL GOVERNMENTS IN AUSTRALIA
Authors: SIMMONS PHIL , DOLLERY BRIAN
Published: January 2019

Shortfalls in infrastructure expenditure represent a ubiquitous problem in all Australian local government systems as well as in many other countries. In this paper, we use an evolutionary model to describe how local government investment decisions are made. We demonstrate that fear of reputational damage among elected councilors could cause herding behavior resulting in convergent and overly cautious investment behavior by councils. Under these conditions, divergent viewpoints amongst council members are discouraged and local government may become moribund in its decision-making. We show how this may result in “gaps” in infrastructure investment.
MEASURING THE TECHNICAL EFFICIENCY OF CEMENT INDUSTRY IN PAKISTAN
Authors: ZAKARIA MUHAMMAD , YANG XIUYUN , MUMSHAD SALIHA
Published: January 2019

Using stochastic frontier analysis, the paper measures the technical efficiency of cement industry of Pakistan. For this purpose, technical efficiency is calculated for 16 cement industries using panel data for the period 2000–2016. Two models are estimated to measure the technical efficiency of cement industry, i.e., the industrial model and the macro-model. In the former model, only industry related variables are used, while in the latter model macroeconomic variables are also used as input variables besides industrial variables. The results indicate that all industrial variables, i.e., capital, labor, raw material, repair and maintenance, energy inputs and advertisement have positive effect on production of cement industry measured by net sales. In macro-model, gross domestic product (GDP) growth and exchange rate have significant positive effect on production. It is found that one percent increase in economic growth will increase cement production by 0.061%. Similarly, one percent devaluation in exchange rate will bring 0.855% increase in cement production. The results show that there is 48.4% efficiency in cement industry of Pakistan, which indicates that cement industry in Pakistan is inefficient by 51.6%. It implies that there is a need to improve the efficiency of cement industry. Further, macroeconomic variables should be incorporated while examining the efficiency of cement industry in Pakistan.
Automatic Detection of the Cracks on the Concrete Railway Sleepers
Authors: Tabatabaei Seyed Amir Hossein , Delforouzi Ahmad , Khan Muhammad Hassan , Wesener Tim , Grzegorzek Marcin
Published: January 2019

A vision-based method for detecting the cracks in the concrete sleepers of the railway tracks will be introduced in this paper. The method is able to detect and partially classify the cracks of the concrete sleepers in two successive steps based on the image processing and pattern recognition techniques. The method has been implemented on the acquired image data frames followed by the analysis, experimental, comparison results and evaluation. The presented results are reasonable which indicates the goodness of the introduced method. The preliminary results of this work have been presented in [A. Delforouzi, A. H. Tabatabaei, M. H. Khan and M. Grzegorzek, A vision-based method for automatic crack detection in railway sleepers, in Kurzynski, M., Wozniak, M., Burduk, R. (eds.), Proceedings of the 10th International Conference on Computer Recognition Systems CORES 2017, Polanica Zdroj, Poland. CORES 2017. Advances in Intelligent Systems and Computing, Vol. 578 (Springer, Cham, 2018), pp. 130–139, doi: 10.1007/978-3-319-59162-9_14].
The problem of detecting when two implicit plane algebraic curves are similar
Authors: Alcázar Juan Gerardo , Díaz-Toca Gema M. , Hermoso Carlos
Published: January 2019

We make use of the complex implicit representation in order to provide a deterministic algorithm for checking whether or not two implicit algebraic curves are related by a similarity. The algorithm has been implemented in the computer algebra system Maple 2016. The implementation can be freely downloaded from the webpage of one of the authors. Examples and evidence of the good practical performance of the algorithm are given.
Canonical transformation path to gauge theories of gravity-II: Space-time coupling of spin-0 and spin-1 particle fields
Authors: Struckmeier J. , Muench J. , Liebrich P. , Hanauske M. , Kirsch J. , Vasak D. , Satarov L. , Stoecker H.
Published: January 2019

The generic form of space-time dynamics as a classical gauge field theory has recently been derived, based on only the action principle and on the principle of general relativity. It was thus shown that Einstein’s general relativity is the special case where (i) the Hilbert Lagrangian (essentially the Ricci scalar) is supposed to describe the dynamics of the “free” (uncoupled) gravitational field, and (ii) the energy–momentum tensor is that of scalar fields representing real or complex structureless (spin-[Formula: see text]) particles. It followed that all other source fields — such as vector fields representing massive and nonmassive spin-[Formula: see text] particles — need careful scrutiny of the appropriate source tensor. This is the subject of our actual paper: we discuss in detail the coupling of the gravitational field with (i) a massive complex scalar field, (ii) a massive real vector field, and (iii) a massless vector field. We show that different couplings emerge for massive and nonmassive vector fields. The massive vector field has the canonical energy–momentum tensor as the appropriate source term — which embraces also the energy density furnished by the internal spin. In this case, the vector fields are shown to generate a torsion of space-time. In contrast, the system of a massless and charged vector field is associated with the metric (Hilbert) energy–momentum tensor due to its additional [Formula: see text] symmetry. Moreover, such vector fields do not generate a torsion of space-time. The respective sources of gravitation apply for all models of the dynamics of the “free” (uncoupled) gravitational field — which do not follow from the gauge formalism but must be specified based on separate physical reasoning.
STUDY ON THE FEATURE OF ELECTROMAGNETIC RADIATION UNDER COAL OXIDATION AND TEMPERATURE RISE BASED ON MULTIFRACTAL THEORY
Authors: KONG BIAO , WANG ENYUAN , LI ZENGHUA , LU WEI
Published: January 2019

During coal oxidation and temperature rise, a significantly large amount of electromagnetic radiation (EMR) signals are generated as a result of thermal deformation and thermal cracking. The generation of EMR signal is the comprehensive embodiment of the physical and chemical changes in coal during its oxidation and subsequent heating. Therefore, the generated signals contain complex and rich messages that can reflect the changes in the internal structure of coal. In this work, the characteristics of EMR signal were analyzed by multifractal theory. Multifractal analysis was used to deconstruct EMR signals. Our preliminary study indicated that the multifractal spectrum of the EMR signal had a feature of small probability event. Further analysis demonstrated that the characteristic parameters of EMR signal are quite different at the later heating stage from those at the early heating stage. At the initial stage of coal spontaneous combustion, the multifractal spectrum of the signal is wider, but when coal combustion is reached, the scale range of EMR signal increases significantly, and its structure changes at different temperature ranges. The research results presented provide a basis for monitoring and presenting an early warning of coal spontaneous combustion risk.
A Bidirectional Pounding Tuned Mass Damper and Its Application to Transmission Tower-Line Systems under Seismic Excitations
Authors: Tian Li , Rong Kunjie , Bi Kaiming , Zhang Peng
Published: January 2019

Failures of transmission tower-line systems have frequently occurred during large earthquakes. It is essential to control the excessive vibrations of transmission tower-line systems to ensure their safe operation in such events. This paper numerically investigates the effectiveness of using a novel bidirectional pounding tuned mass damper (BPTMD) to control the seismic responses of transmission tower-line system when subjected to earthquake ground motions. A finite element model of a typical transmission tower-line system with BPTMD is developed using the commercial software ABAQUS, with the accuracy of the results verified against a previous study. The seismic responses of the system with and without BPTMD are calculated. For comparison, the control effect of using the conventional bidirectional tuned mass damper is also calculated and discussed. Finally, a parametric study is performed to investigate the effects of the mass ratio, seismic intensity, gap size and frequency ratio on the seismic response of the system, while optimal design parameters are obtained.
A valence bond study of the activation of methyl halides bonds by electric fields
Authors: Pozo-Guerrón Paúl , Armijos-Capa Gerardo , Rincón Luis , Mora José R. , Torres F. Javier , Rodríguez Vladimir
Published: January 2019

In the present work, the activation of methyl halides bonds under experience of an external electric field (EEF) is explained from the Valence Bond theory perspective. The dissociation mechanism of C–X bonds (X [Formula: see text] Cl, Br, I) influenced by a homogeneous and a heterogeneous field placed parallel to the bond axis is presented. For all examples, an increase in the electric field strength have similar consequences: (i) the decrease of the energy depth along the dissociation path, (ii) an increase of the equilibrium interatomic distance (at high EEFs), and (iii) the transition from a homolytic to a heterolytic dissociation after some field magnitude. These general behaviors are explained through the curve crossing between the ionic and the covalent structure at some field strength.
Power and free normal subgroups of generalized Hecke groups
Authors: Sahin Recep , Meral Taner , Koruoğlu Özden
Published: January 2019

Let [Formula: see text] and [Formula: see text] be integers such that [Formula: see text] [Formula: see text] and let [Formula: see text] be generalized Hecke group associated to [Formula: see text] and [Formula: see text] Generalized Hecke group [Formula: see text] is generated by [Formula: see text] and [Formula: see text], where [Formula: see text] and [Formula: see text] In this paper, for positive integer [Formula: see text] we study the power subgroups [Formula: see text] of generalized Hecke groups [Formula: see text]. Also, we give some results about free normal subgroups of generalized Hecke groups [Formula: see text]
Group algebras of Lie nilpotency index 14
Authors: Bhatt Suchi , Chandra Harish , Sahai Meena
Published: January 2019

Let [Formula: see text] be a group and let [Formula: see text] be a field of characteristic [Formula: see text]. Lie nilpotent group algebras of strong Lie nilpotency index at most 13 have been classified by many authors. In this paper, our aim is to classify the group algebras [Formula: see text] which are strongly Lie nilpotent of index 14.
Design and Analysis of Thermoacoustic Refrigerators Using Air as Working Substance
Authors: Prashantha B. G. , Seetharamu S. , Narasimham G. S. V. L. , Kumar M. R. Praveen
Published: January 2019

In this paper, the design of 50 W thermoacoustic refrigerators operating with air as working substance at 10 bar pressure and 3% drive ratio for a temperature difference of 28 K is described. The design strategies discussed in this paper help in design and development of low cost thermoacoustic coolers compared to helium as the working substance. The design and optimization of spiral stack and heat exchangers, and the promising 0.2[Formula: see text] and 0.15[Formula: see text] resonator design with taper and divergent section with hemispherical end are discussed. The surface area, volume, length and power density of the hemispherical end design with air as working substance is found better compared to the published 10 and 50 W coolers using helium as the working substance. The theoretical design results are validated using DeltaEC software simulation results. The DeltaEC predicts 51.4% improvement in COP (1.273) at the cold heat exchanger temperature of [Formula: see text]C with air as working substance for the 50[Formula: see text]W 0.15[Formula: see text]TDH resonator design compared to the published 50[Formula: see text]W 0.25[Formula: see text]TDH resonator design with helium as working substance.
An Experimental Investigation of Flow Patterns During Condensation of HFC Refrigerants in Horizontal Micro-Fin Tubes
Authors: Singh Sanjeev , Kukreja Rajeev
Published: January 2019

Condensation heat transfer coefficients and flow regimes in two different horizontal micro-fin tubes are examined during the condensation of refrigerants R-134a and R-410A. The present investigation has focused on determination and prediction of condensation heat transfer coefficients and finding the interrelation between heat transfer coefficients and the prevailing flow regimes. During flow visualization, flow regimes have been captured using borosilicate glass tube at inlet and outlet of the test condenser using high speed digital camera. Stratified, stratified wavy, wavy annular, annular, slug and plug flows have been observed at different mass fluxes and vapor qualities of the refrigerants. The observed flow regimes are compared with the existing flow regime maps proposed by Breber et al. [Prediction of horizontal tube side condensation of pure components using flow regime criteria, J. Heat Transfer 102 (1980) 471–476], Tandon et al. [A new flow regime map for condensation inside horizontal tubes, J. Heat Transfer 104 (1982) 763–768.] and Thome et al. [Condensation in horizontal tubes, part 2: New heat transfer model based on flow regimes, Int. J. Heat Mass Transfer 46 (2003) 3365–3387.] Thome et al. [Condensation in horizontal tubes, part 2: New heat transfer model based on flow regimes, Int. J. Heat Mass Transfer 46 (2003) 3365–3387.] flow regime map shows good agreement with experimental data.