bluuebunny/crossref_metadata_2025 huggingface dataset:
Snoring and environmental exposure: results from the Swedish GA2LEN study
Authors: Silverforsen Daniel , Theorell-Haglöw Jenny , Ljunggren Mirjam , Middelveld Roelinde , Wang Juan , Franklin Karl , Norbäck Dan , Lundbäck Bo , Forsberg Bertil , Lindberg Eva , Janson Christer
Published: June 2021

Objective

Habitual snoring is associated with fatigue, headaches and low work performance. This cross-sectional study aimed to investigate if snoring is affected by environmental factors such as home dampness and exposure to air pollution.

Setting

General population sample from four Swedish cities.

Participants

25 848 participants from the Swedish part of the epidemiological Global Asthma and Allergy and European network of excellence study carried out in 2008. The participants completed a postal questionnaire on snoring and, indoor and outdoor environmental exposure as well as potential confounders including smoking, weight, height and educational level.

Results

Of the participants, 4211 (16.3%) were habitual snorers. Habitual snorers reported water damage (8.3% vs 7.0% p<0.0001), floor dampness (4.6% vs 3.8% % p<0.0001) and visible mould (5.2% vs 3.8% p<0.0001) in their homes more often than non-snorers. Habitual snorers stated being annoyed by air pollution more often than non-snorers with habitual snorers reporting being irritated with the air in their residential area to a higher extent (sometimes 16.2% vs 13.9%, and daily 4.6% vs 3.1%) as well as annoyance from traffic fumes (somewhat 19% vs 18.5% and very 5% vs 3.6%) (p<0.0001). These results remained significant after adjustment for age, body mass index, smoking history and educational level.

Conclusion

Snoring is more prevalent in subjects reporting home dampness and air pollution. These association should be confirmed in further research using objective measurements and a longitudinal approach.
Health effects of climate change: an overview of systematic reviews
Authors: Rocque Rhea J , Beaudoin Caroline , Ndjaboue Ruth , Cameron Laura , Poirier-Bergeron Louann , Poulin-Rheault Rose-Alice , Fallon Catherine , Tricco Andrea C , Witteman Holly O
Published: June 2021

Objectives

We aimed to develop a systematic synthesis of systematic reviews of health impacts of climate change, by synthesising studies’ characteristics, climate impacts, health outcomes and key findings.

Design

We conducted an overview of systematic reviews of health impacts of climate change. We registered our review in PROSPERO (CRD42019145972). No ethical approval was required since we used secondary data. Additional data are not available.

Data sources

On 22 June 2019, we searched Medline, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Cochrane and Web of Science.

Eligibility criteria

We included systematic reviews that explored at least one health impact of climate change.

Data extraction and synthesis

We organised systematic reviews according to their key characteristics, including geographical regions, year of publication and authors’ affiliations. We mapped the climate effects and health outcomes being studied and synthesised major findings. We used a modified version of A MeaSurement Tool to Assess systematic Reviews-2 (AMSTAR-2) to assess the quality of studies.

Results

We included 94 systematic reviews. Most were published after 2015 and approximately one-fifth contained meta-analyses. Reviews synthesised evidence about five categories of climate impacts; the two most common were meteorological and extreme weather events. Reviews covered 10 health outcome categories; the 3 most common were (1) infectious diseases, (2) mortality and (3) respiratory, cardiovascular or neurological outcomes. Most reviews suggested a deleterious impact of climate change on multiple adverse health outcomes, although the majority also called for more research.

Conclusions

Most systematic reviews suggest that climate change is associated with worse human health. This study provides a comprehensive higher order summary of research on health impacts of climate change. Study limitations include possible missed relevant reviews, no meta-meta-analyses, and no assessment of overlap. Future research could explore the potential explanations between these associations to propose adaptation and mitigation strategies and could include broader sociopsychological health impacts of climate change.
How can human-centered design build a story-based video intervention that addresses vaccine hesitancy and bolsters vaccine confidence in the Philippines? A mixed method protocol for project SALUBONG
Authors: Reñosa Mark Donald C. , Wachinger Jonas , Bärnighausen Kate , Aligato Mila F. , Landicho-Guevarra Jhoys , Endoma Vivienne , Landicho Jeniffer , Bravo Thea Andrea , Demonteverde Maria Paz , Guevarra Jerric Rhazel , de Claro Nicanor , Inobaya Marianette , Adam Maya , Chase Rachel P. , McMahon Shannon A.
Published: June 2021

Introduction

Since the onset of a dengue vaccine controversy in late 2017, vaccine confidence has plummeted in the Philippines, leading to measles and polio outbreaks in early 2019. This protocol outlines a human-centered design (HCD) approach to co-create and test an intervention that addresses vaccine hesitancy (VH) via narrative and empathy with and among families and healthcare workers.

Methods and analysis

‘Salubong’ is a Filipino term that means to welcome someone back into one’s life, reinforcing notions of family ties and friendships. We apply this sentiment to vaccines. Following the phases of HCD, guided by a theoretical framework, and drawing from locally held understandings of faith and acceptance, we will conduct in-depth interviews (IDIs) and focus group discussions (FGDs) in rural and urban Filipino communities that witnessed dramatic increases in measles cases in recent years. During qualitative engagements with caretakers, providers, and policymakers, we will collect narratives about family and community perceptions of childhood vaccinations, public health systems and opportunities to restore faith. IDIs and FGDs will continuously inform the development of (and delivery mechanisms for) story-based interventions. Once developed, we will test our co-created interventions among 800 caretakers and administer a VH questionnaire prior to and immediately following the intervention encounter. We will use the feedback gained through the survey and Kano-style questionnaires to further refine the intervention. Considering the data collection challenges posed by the ongoing COVID-19 pandemic, we have developed workarounds to conduct data collection primarily online. We will use systematic online debriefings to facilitate comprehensive participation of the full research team.

Ethics and dissemination

Ethical approval has been granted by the Institutional Review Board of the Research Institute for Tropical Medicine (number 2019–44) and Ethical Commission of Heidelberg University, Faculty of Medicine (S-833/2019). Study findings will be disseminated in scientific conferences and published in peer-reviewed journals.
Early diagnosis of mortality using admission CT perfusion in severe traumatic brain injury patients (ACT-TBI): protocol for a prospective cohort study
Authors: Alcock Susan , Batoo Divjeet , Ande Sudharsana Rao , Grierson Rob , Essig Marco , Martin Douglas , Trivedi Anurag , Sinha Namita , Leeies Murdoch , Zeiler Frederick A , Shankar Jai Jai Shiva
Published: June 2021

Introduction

Severe traumatic brain injury (TBI) is a catastrophic neurological condition with significant economic burden. Early in-hospital mortality (<48 hours) with severe TBI is estimated at 50%. Several clinical examinations exist to determine brain death; however, most are difficult to elicit in the acute setting in patients with severe TBI. Having a definitive assessment tool would help predict early in-hospital mortality in this population. CT perfusion (CTP) has shown promise diagnosing early in-hospital mortality in patients with severe TBI and other populations. The purpose of this study is to validate admission CTP features of brain death relative to the clinical examination outcome for characterizing early in-hospital mortality in patients with severe TBI.

Methods and analysis

The Early Diagnosis of Mortality using Admission CT Perfusion in Severe Traumatic Brain Injury Patients study, is a prospective cohort study in patients with severe TBI funded by a grant from the Canadian Institute of Health Research. Adults aged 18 or older, with evidence of a severe TBI (Glasgow Coma Scale score ≤8 before initial resuscitation) and, on mechanical ventilation at the time of imaging are eligible. Patients will undergo CTP at the time of first imaging on their hospital admission. Admission CTP compares with the reference standard of an accepted bedside clinical assessment for brainstem function. Deferred consent will be used. The primary outcome is a binary outcome of mortality (dead) or survival (not dead) in the first 48 hours of admission. The planned sample size for achieving a sensitivity of 75% and a specificity of 95% with a CI of ±5% is 200 patients.

Ethics and dissemination

This study has been approved by the University of Manitoba Health Research Ethics Board. The findings from our study will be disseminated through peer-reviewed journals and presentations at local rounds, national and international conferences. The public will be informed through forums at the end of the study.

Trial registration number

NCT04318665
SporTRIA study—a multicentre trial protocol for excretion kinetics of triamcinolone acetonide following sport-related intra-articular injections in knees: definitions of the washout periods
Authors: Allado Edem , Poussel Mathias , Gambier Nicolas , Saunier Véronique , Starck Marjorie , Buisson Corinne , Cinquetti Gael , Albuisson Eliane , Chenuel Bruno
Published: June 2021

Introduction

Intra-articular (IA) and peri-articular glucocorticoid (GC) injections are common in sports medicine. However, from 1 January 2022, all injectable GC routes (including IA administration) will be prohibited in-competition by World Anti-Doping Agency (WADA). Owing to these rules, an IA GC treatment out-of-competition could result in an adverse analytical finding in-competition if the washout period is not clearly defined. The aim of this study is to determine the urinary excretion profile of triamcinolone acetonide following IA injection to strengthen the definition of the washout periods.

Methods and analysis

This is a prospective multicentre trial to include 20 subjects who practice sports for at least 4 hours/week and present a knee disorder requiring IA injection of triamcinolone acetonide for therapeutic purposes. To determine the excretion profile of triamcinolone acetonide in both urine and blood following IA injection of the drug, We will perform 20 urinary tests and 20 dried blood spot tests, two prior to GC injection (baseline) and the last one at 35 days. Analyses will be performed by the French antidoping agency laboratory in accordance with WADA standards and regulations.

Ethics and dissemination

The study protocol was approved by the French ethics committee (CPP Sud Est III—Lyon—2020-070B on 06 October 2020). All subjects will provide written informed consent. The results of this study will be accessible in peer-reviewed publication and be presented at academic conference.

Trial registration number

NCT04574232.
Health extension workers’ perceived health system context and health post preparedness to provide services: a cross-sectional study in four Ethiopian regions
Authors: Getachew Theodros , Abebe Solomon Mekonnen , Yitayal Mezgebu , Bergström Anna , Persson Lars-Ake , Berhanu Della
Published: June 2021

Objective

The health system context influences the implementation of evidence-based practices and quality of healthcare services. Ethiopia aims at reaching universal health coverage but faces low primary care utilisation and substandard quality of care. We assessed the health extension workers’ perceived context and the preparedness of health posts to provide services.

Setting

This study was part of evaluating a complex intervention in 52 districts of four regions of Ethiopia. This paper used the endline data collected from December 2018 to February 2019.

Participants

A total of 152 health posts and health extension workers serving selected enumeration areas were included.

Outcome measures

We used the Context Assessment for Community Health (COACH) tool and the Service Availability and Readiness Assessment tool.

Results

Internal reliability of COACH was satisfactory. The dimensionscommunity engagement,work culture,commitment to workandleadershipall scored high (mean 3.75–4.01 on a 1–5 scale), whileorganisational resources, sources of knowledgeandinformal paymentsscored low (1.78–2.71). The general service readiness index was 59%. On average, 67% of the health posts had basic amenities to provide services, 81% had basic equipment, 42% had standard precautions for infection prevention, 47% had test capacity for malaria and 58% had essential medicines.

Conclusion

The health extension workers had a good relationship with the local community, used data for planning, were highly committed to their work with positive perceptions of their work culture, a relatively positive attitude regarding their leaders, and reported no corruption or informal payments. In contrast, they had insufficient sources of information and a severe lack of resources. The health post preparedness confirmed the low level of resources and preparedness for services. These findings suggest a significant potential contribution by health extension workers to Ethiopia’s primary healthcare, provided that they receive improved support, including new information and essential resources.
Unintended health consequences of Swedish parental leave policy (ParLeHealth): protocol for a quasi-experimental study
Authors: Juárez Sol Pia , Honkaniemi Helena , Heshmati Amy F , Debiasi Enrico , Dunlavy Andrea , Hjern Anders , Rostila Mikael , Mussino Eleonora , Katikireddi Srinivasa Vittal , Duvander Ann-Zofie
Published: June 2021

Introduction

Sweden has long been praised for a generous parental leave policy oriented towards facilitating a gender-equitable approach to work and parenting. Yet certain aspects of Swedish parental leave could also be responsible for the maintenance of (or even the increase in) health inequalities. Using a ‘Health in All Policies’ lens, this research project aims to assess the unintended health consequences of various components of Sweden’s parental leave policy, including eligibility for and uptake of earnings based benefits.

Methods and analysis

We will use individual-level data from multiple Swedish registers. Sociodemographic information, including parental leave use, will be retrieved from the total population register, Longitudinal Integration Database for Health Insurance and Labour Market Studies and Social Insurance Agency registers. Health information for parents and children will be retrieved from the patient, prescribed drug, cause of death, medical birth and children’s health registers. We will evaluate parents’ mental, mothers’ reproductive and children’s general health outcomes in relation to several policy reforms aiming to protect parental leave benefits in short birth spacing (the speed premium) and to promote father’s uptake (the father’s quota) and sharing of parental leave days (the double days reform). We will also examine effects of increases in basic parental leave benefit levels. Using quasi-experimental designs, we will compare health outcomes across these reforms and eligibility thresholds with interrupted time series, difference-in-difference and regression discontinuity approaches to reduce the risk of health selection and assess causality in the link between parental leave use and health.

Ethics and dissemination

This project has been granted all necessary ethical permissions from the Stockholm Regional Ethical Review Board (Dnr 2019-04913) for accessing and analysing deidentified data. The final outputs will primarily be disseminated as scientific articles published in open-access, high-impact peer-reviewed international journals, as well as press releases and policy briefs.
Prevention of dementia using mobile phone applications (PRODEMOS): protocol for an international randomised controlled trial
Authors: Eggink Esmé , Hafdi Melanie , Hoevenaar-Blom Marieke P , Song Manshu , Andrieu Sandrine , Barnes Linda E , Birck Cindy , Brooks Rachael L , Coley Nicola , Ford Elizabeth , Georges Jean , van der Groep Abraham , van Gool Willem A , Handels Ron , Hou Haifeng , Li Dong , Liu Hongmei , Lyu Jihui , van Marwijk Harm , van der Meijden Mark , Niu Yixuan , Sadhwani Shanu , Wang Wenzhi , Wang Youxin , Wimo Anders , Ye Xiaoyan , Yu Yueyi , Zeng Qiang , Zhang Wei , Wang Wei , Brayne Carol , Moll van Charante Eric P , Richard Edo
Published: June 2021

Introduction

Profiles of high risk for future dementia are well understood and are likely to concern mostly those in low-income and middle-income countries and people at greater disadvantage in high-income countries. Approximately 30%–40% of dementia cases have been estimated to be attributed to modifiable risk factors, including hypertension, smoking and sedentary lifestyle. Tailored interventions targeting these risk factors can potentially prevent or delay the onset of dementia. Mobile health (mHealth) improves accessibility of such prevention strategies in hard-to-reach populations while at the same time tailoring such approaches. In the current study, we will investigate the effectiveness and implementation of a coach-supported mHealth intervention, targeting dementia risk factors, to reduce dementia risk.

Methods and analysis

The prevention of dementia using mobile phone applications (PRODEMOS) randomised controlled trial will follow an effectiveness–implementation hybrid design, taking place in the UK and China. People are eligible if they are 55–75 years old, of low socioeconomic status (UK) or from the general population (China); have ≥2 dementia risk factors; and own a smartphone. 2400 participants will be randomised to either a coach-supported, interactive mHealth platform, facilitating self-management of dementia risk factors, or a static control platform. The intervention and follow-up period will be 18 months. The primary effectiveness outcome is change in the previously validated Cardiovascular Risk Factors, Ageing and Incidence of Dementia dementia risk score. The main secondary outcomes include improvement of individual risk factors and cost-effectiveness. Implementation outcomes include acceptability, adoption, feasibility and sustainability of the intervention.

Ethics and dissemination

The PRODEMOS trial is sponsored in the UK by the University of Cambridge and is granted ethical approval by the London—Brighton and Sussex Research Ethics Committee (reference: 20/LO/01440). In China, the trial is approved by the medical ethics committees of Capital Medical University, Beijing Tiantan Hospital, Beijing Geriatric Hospital, Chinese People’s Liberation Army General Hospital, Taishan Medical University and Xuanwu Hospital. Results will be published in a peer-reviewed journal.

Trial registration number

ISRCTN15986016.
The Optimising Cardiac Surgery ouTcOmes in People with diabeteS (OCTOPuS) randomised controlled trial to evaluate an outpatient pre-cardiac surgery diabetes management intervention: a study protocol
Authors: Holt Richard Ian Gregory , Dritsakis Giorgos , Barnard-Kelly Katharine , Thorne Kerensa , Whitehead Amy , Cohen Lauren , Dixon Elizabeth , Patel Mayank , Newland-Jones Philip , Green Mark , Partridge Helen , Luthra Suvitesh , Ohri Sunil , Salhiyyah Kareem , Lord Joanne , Niven John , Cook Andrew
Published: June 2021

Introduction

Cardiothoracic surgical outcomes are poorer in people with diabetes compared with those without diabetes. There are two important uncertainties in the management of people with diabetes undergoing major surgery: (1) how to improve diabetes management in the weeks leading up to an elective procedure and (2) whether that improved management leads to better postoperative outcomes. We previously demonstrated the feasibility of delivering the Optimising Cardiac Surgery ouTcOmes in People with diabeteS (OCTOPuS) intervention, an outpatient intervention delivered by diabetes healthcare professionals for people with suboptimally managed diabetes over 8–12 weeks before elective cardiac surgery. The present study will assess the clinical and cost-effectiveness of the intervention in cardiothoracic centres across the UK.

Methods and analysis

A multicentre, parallel group, single-blinded 1:1 individually randomised trial comparing time from surgery until clinically fit for discharge in adults with suboptimally managed type 1 diabetes or type 2 diabetes undergoing elective surgery between the OCTOPuS intervention and usual care (primary endpoint). Secondary endpoints will include actual time from surgery to discharge from hospital; days alive and either out of hospital or judged as clinically fit for discharge; mortality; time on intensive therapy unit (ITU)/ventilator; infections; acute myocardial infarction; change in weight; effect on postoperative renal function and incidence of acute kidney injury; change in HbA1c; frequency and severity of self-reported hypoglycaemia; operations permanently cancelled for suboptimal glycaemic levels; cost-effectiveness; psychosocial questionnaires. The target sample size will be 426 recruited across approximately 15 sites. The primary analysis will be conducted on an intention-to-treat population. A two-sided p value of 0.05 or less will be used to declare statistical significance for all analyses and results will be presented with 95% CIs.

Ethics and dissemination

The trial was approved by the South Central–Hampshire A Research Ethics Committee (20/SC/0271). Results will be disseminated through conferences, scientific journals, newsletters, magazines and social media.

Trial registration number

ISRCTN10170306.
Dysosmobacter welbionis is a newly isolated human commensal bacterium preventing diet-induced obesity and metabolic disorders in mice
Authors: Le Roy Tiphaine , Moens de Hase Emilie , Van Hul Matthias , Paquot Adrien , Pelicaen Rudy , Régnier Marion , Depommier Clara , Druart Céline , Everard Amandine , Maiter Dominique , Delzenne Nathalie M , Bindels Laure B , de Barsy Marie , Loumaye Audrey , Hermans Michel P , Thissen Jean-Paul , Vieira-Silva Sara , Falony Gwen , Raes Jeroen , Muccioli Giulio G , Cani Patrice D
Published: June 2021

Objective

To investigate the abundance and the prevalence of Dysosmobacter welbionis J115T, a novel butyrate-producing bacterium isolated from the human gut both in the general population and in subjects with metabolic syndrome. To study the impact of this bacterium on host metabolism using diet-induced obese and diabetic mice.

Design

We analysed the presence and abundance of the bacterium in 11 984 subjects using four human cohorts (ie, Human Microbiome Project, American Gut Project, Flemish Gut Flora Project and Microbes4U). Then, we tested the effects of daily oral gavages with live D. welbionis J115T on metabolism and several hallmarks of obesity, diabetes, inflammation and lipid metabolism in obese/diabetic mice.

Results

This newly identified bacterium was detected in 62.7%–69.8% of the healthy population. Strikingly, in obese humans with a metabolic syndrome, the abundance of Dysosmobacter genus correlates negatively with body mass index, fasting glucose and glycated haemoglobin. In mice, supplementation with live D. welbionis J115T, but not with the pasteurised bacteria, partially counteracted diet-induced obesity development, fat mass gain, insulin resistance and white adipose tissue hypertrophy and inflammation. In addition, live D. welbionis J115T administration protected the mice from brown adipose tissue inflammation in association with increased mitochondria number and non-shivering thermogenesis. These effects occurred with minor impact on the mouse intestinal microbiota composition.

Conclusions

These results suggest that D. welbionis J115T directly and beneficially influences host metabolism and is a strong candidate for the development of next-generation beneficial bacteria targeting obesity and associated metabolic diseases.
Efficacy of interventions to increase physical activity for people with heart failure: a meta-analysis
Authors: Amirova Aliya , Fteropoulli Theodora , Williams Paul , Haddad Mark
Published: June 2021

Objectives

This meta-analysis aims to (1) evaluate the efficacy of physical activity interventions in heart failure and (2) to identify intervention characteristics significantly associated with the interventions’ efficacy.

Methods

Randomised controlled trials reporting intervention effects on physical activity in heart failure were combined in a meta-analysis using a random-effect model. Exploratory meta-analysis was performed by specifying the general approach (eg, cardiac rehabilitation), strategies used (eg, action planning), setting (eg, centre based), mode of delivery (eg, face to face or online), facilitator (eg, nurse), contact time and behavioural change theory use as predictors in the random-effect model.

Results

Interventions (n=21) had a significant overall effect (SMD=0.54, 95% CI (0.13 to 0.95), p<0.0005). Combining an exercise programme with behavioural change intervention was found efficacious (SMD=1.26, 95% CI (0.26 to 2.26), p<0.05). Centre-based (SMD=0.98, 95% CI (0.35 to 1.62), and group-based (SMD=0.89, 95% CI (0.29 to 1.50),) delivery by a physiotherapist (SMD=0.84, 95% CI (0.03 to 1.65),) were significantly associated with efficacy. The following strategies were identified efficacious: prompts/cues (SMD=3.29, 95% CI (1.97 to 4.62)), credible source (standardised mean difference, SMD=2.08, 95% CI (0.95;3.22)), adding objects to the environment (SMD=1.47, 95% CI (0.41 to 2.53)), generalisation of the target behaviour SMD=1.32, 95% CI (0.22 to 2.41)), monitoring of behaviour by others without feedback (SMD=1.02, 95% CI (0.05 to 1.98)), self-monitoring of outcome(s) of behaviour (SMD=0.79, 95% CI (0.06 to 1.52), graded tasks (SMD=0.73, 95% CI (0.22 to 1.24)), behavioural practice/rehearsal (SMD=0.72, 95% CI (0.26 to 1.18)), action planning (SMD=0.62, 95% CI (0.03 to 1.21)) and goal setting (behaviour) (SMD=0.56, 95% CI (0.03 to 1.08)).

Conclusion

The meta-analysis suggests intervention characteristics that may be suitable for promoting physical activity in heart failure. There is moderate evidence in support of an exercise programme combined with a behavioural change intervention delivered by a physiotherapist in a group-based and centre-based settings.

PROSPERO registeration

CRD42015015280.
Rotating behind Privacy: An Improved Lightweight Authentication Scheme for Cloud-based IoT Environment
Authors: Chaudhry Shehzad Ashraf , Irshad Azeem , Yahya Khalid , Kumar Neeraj , Alazab Mamoun , Zikria Yousaf Bin
Published: June 2021

The advancements in the internet of things (IoT) require specialized security protocols to provide unbreakable security along with computation and communication efficiencies. Moreover, user privacy and anonymity has emerged as an integral part, along with other security requirements. Unfortunately, many recent authentication schemes to secure IoT-based systems were either proved as vulnerable to different attacks or prey of inefficiencies. Some of these schemes suffer from a faulty design that happened mainly owing to undue emphasis on privacy and anonymity alongside performance efficiency. This article aims to show the design faults by analyzing a very recent hash functions-based authentication scheme for cloud-based IoT systems with misunderstood privacy cum efficiency tradeoff owing to an unadorned design flaw, which is also present in many other such schemes. Precisely, it is proved in this article that the scheme of Wazid et al. cannot provide mutual authentication and key agreement between a user and a sensor node when there exists more than one registered user. We then proposed an improved scheme and proved its security through formal and informal methods. The proposed scheme completes the authentication cycle with a minor increase in computation cost but provides all security goals along with privacy.
Dynamics and Solutions’ Expressions of a Higher-Order Nonlinear Fractional Recursive Sequence
Authors: Alshareef Abeer , Alzahrani Faris , Khan Abdul Qadeer
Published: June 2021

The principle purpose of this article is to examine some stability properties for the fixed point of the below rational difference equationUn+1=ξUn−8+εUn−82/μUn−8+κUn−17whereξ,ε,μ, andκare arbitrary real numbers. Moreover, solutions for some special cases of the proposed difference equation are introduced.
Analytical Properties of the Generalized Heat Matrix Polynomials Associated with Fractional Calculus
Authors: Abdalla Mohamed , Boulaaras Salah Mahmoud
Published: June 2021

In this paper, we introduce a matrix version of the generalized heat polynomials. Some analytic properties of the generalized heat matrix polynomials are obtained including generating matrix functions, finite sums, and Laplace integral transforms. In addition, further properties are investigated using fractional calculus operators.
Automatic Recognition of Communication Signal Modulation Based on the Multiple‐Parallel Complex Convolutional Neural Network
Authors: Huang Zhen , Li Chengkang , Lv Qiang , Su Rijian , Zhou Kaibo
Published: June 2021

This paper implements a deep learning‐based modulation pattern recognition algorithm for communication signals using a convolutional neural network architecture as a modulation recognizer. In this paper, a multiple‐parallel complex convolutional neural network architecture is proposed to meet the demand of complex baseband processing of all‐digital communication signals. The architecture learns the structured features of the real and imaginary parts of the baseband signal through parallel branches and fuses them at the output according to certain rules to obtain the final output, which realizes the fitting process to the complex numerical mapping. By comparing and analyzing several commonly used time‐frequency analysis methods, a time‐frequency analysis method that can well highlight the differences between different signal modulation patterns is selected to convert the time‐frequency map into a digital image that can be processed by a deep network. In order to fully extract the spatial and temporal characteristics of the signal, the CLP algorithm of the CNN network and LSTM network in parallel is proposed. The CNN network and LSTM network are used to extract the spatial features and temporal features of the signal, respectively, and the fusion of the two features as well as the classification is performed. Finally, the optimal model and parameters are obtained through the design of the modulation recognizer based on the convolutional neural network and the performance analysis of the convolutional neural network model. The simulation experimental results show that the improved convolutional neural network can produce certain performance gains in radio signal modulation style recognition. This promotes the application of machine learning algorithms in the field of radio signal modulation pattern recognition.
A Conservative Crank-Nicolson Fourier Spectral Method for the Space Fractional Schrödinger Equation with Wave Operators
Authors: Zhang Lei , Yang Rui , Zhang Li , Wang Lisha
Published: June 2021

In this paper, the Crank-Nicolson Fourier spectral method is proposed for solving the space fractional Schrödinger equation with wave operators. The equation is treated with the conserved Crank-Nicolson Fourier Galerkin method and the conserved Crank-Nicolson Fourier collocation method, respectively. In addition, the ability of the constructed numerical method to maintain the conservation of mass and energy is studied in detail. Meanwhile, the convergence with spectral accuracy in space and second-order accuracy in time is verified for both Galerkin and collocation approximations. Finally, the numerical experiments verify the properties of the conservative difference scheme and demonstrate the correctness of theoretical results.
South Africa Crime Visualization, Trends Analysis, and Prediction Using Machine Learning Linear Regression Technique
Authors: Obagbuwa Ibidun Christiana , Abidoye Ademola P.
Published: June 2021

South Africa has been classified as one of the most homicidal, violent, and dangerous places across the globe. However, the two elements that pushed South Africa high in the crime rank are the rates of social violence and homicide. It was reported by Business Insider that South Africa is among the most top 15 ferocious nations on earth. By 1995, South Africa was rated the second highest in terms of murder. However, the crime rate has reduced for some years and suddenly rose again in recent years. Due to social violence and crime rates in South Africa, foreign investors are no longer interested in continuing or starting a business with the nation, and hence, its economy is declining. South Africa’s government is looking for solutions to the crime issue and to redeem the image of the country in terms of high crime ranking and boost the confidence of the investors. Many traditional approaches to data analysis in crime-related studies have been done in South Africa, but the machine learning approach has not been adequately considered. The police station and many other agencies that deal with crime hold a lot of databases that can be used to predict or analyze criminal happenings across the provinces of South Africa. This research work aimed at offering a solution to the problem by building a model that can predict crime. The machine learning approach shall be used to extract useful information from South Africa's nine provinces' crime data. A crime prediction system that can analyze and predict crime is proposed. To accomplish this, South Africa crime data on 27 crime categories were obtained from the popular data repository “Kaggle.” Diverse data analytics steps were applied to preprocess the datasets, and a machine learning algorithm (linear regression) was used to build a predictive model to analyze data and predict future crime. The appropriate authorities and security agencies in South Africa can have insight into the crime trends and alleviate them to encourage the foreign stakeholders to continue their businesses.
A Pulmonary Artery-Vein Separation Algorithm Based on the Relationship between Subtrees Information
Authors: Yu Kun , Zhang Ziming , Li Xiaoshuo , Liu Pan , Zhou Qinghua , Tan Wenjun
Published: June 2021

Physicians need to distinguish between pulmonary arteries and veins when diagnosing diseases such as chronic obstructive pulmonary disease (COPD) and lung tumors. However, manual differentiation is difficult due to various factors such as equipment and body structure. Unlike previous geometric methods of manually selecting the points of seeds and using neural networks for separation, this paper proposes a combined algorithm for pulmonary artery-vein separation based on subtree relationship by implementing a completely new idea and combining global and local information, anatomical knowledge, and two-dimensional region growing method. The algorithm completes the reconstruction of the whole vascular structure and the separation of adhesion points from the tree-like structure characteristics of blood vessels, after which the automatic classification of arteries and veins is achieved by using anatomical knowledge, and the whole process is free from human intervention. After comparing all the experimental results with the gold standard, we obtained an average separation accuracy of 85%, which achieved effective separation. Meanwhile, the time range could be controlled between 40 s and 50 s, indicating that the algorithm has good stability.
A Possible Flow Cytometry‐Based Viability and Vitality Assessment Protocol for Pathogenic Vibrio cholerae O1 and O139 Postexposure to Simulated Gastric Fluid
Authors: Singh Atheesha , Barnard Tobias George
Published: June 2021

During the intake of contaminated water, for diarrheal disease to occur, Vibrio cholerae must survive through the bactericidal digestive secretion of gastric fluid during passage through the stomach. Determining the viability of these bacteria is challenging, with the standard cultivation methods for viability being time‐consuming and unable to culture cells that may still function accordingly. This study assessed the use of enzyme action and membrane integrity as alternatives for determining vitality and viability, respectively, in gastric acid‐stressed pathogenic Vibrio cholerae O1 and O139, using fluorescent probes thiazole orange (TO) for viability based on membrane integrity, carboxyfluorescein diacetate (CFDA) with acetoxymethyl ester (AM) for vitality based on metabolic activity, and propidium iodide (PI) for cell death/damage due to loss of membrane integrity, with flow cytometry. Simulated gastric fluid‐treated bacterial cells were labelled with blends of TO+PI and CFDA‐AM+PI, and these stained cells were separated into heterologous populations based on their fluorescence signal. The gastric acid exposed cells presented with high green fluorescence signals after staining with the metabolic probe CFDA‐AM, which indicated intact (live) cells due to being metabolically active, whereas when the same cells were stained with the DNA probe (TO), these appeared to be in a “stressed state” due to loss of membrane integrity. Damaged cells (dead cells) showed high red fluorescence levels after staining with PI probe. The use of flow cytometry with fluorescent probes is a favorable method for evaluating the vitality and viability of bacteria when cells are labelled with a combination of CFDA‐AM+PI.
The Evolutionary Characteristics of Reservoir Microstructure under Long-Term Waterflooding Development and Its Fractal Description
Authors: Wang Fengjiao , Wang Xu , Liu Yikun , Deng Qingjun , Xu Jianjun , Zhang Yong , Li Huaiyuan
Published: June 2021

Generally, long-term waterflooding development often leads to the change of reservoir pore and clay mineral composition, which results in the change of permeability and wettability. In order to explore the relationship between core micropore structure and water cut, based on physical simulation experiments and fractal theory, we proposed a fractal evolutionary model to describe the evolution characteristics of microstructure of long-term water driving reservoirs. In this paper, core pore structure by SEM was first conducted to analyze the change of core pore structure before and after waterflooding under the conditions of magnification of 200 times, 800 times, and 2000 times, respectively. Then, conventional and constant rate mercury injection tests were combined to perform the comparative analysis of core structural parameters before and after waterflooding. Finally, a micropore-throat structure evolution model of core was established. Research shows that the connectivity of larger pores becomes better after long-term water driving, the degree of heterogeneity weakens, and the micro heterogeneity of small pores becomes stronger and stronger. The throat characteristics change in a complex manner, the radius tends to increase, and the sorting becomes better, while the connectivity of small throat changes complex. In general, the heterogeneity of throat increases with the time of water injection in reservoirs with low porosity and permeability. On the basis of fractal theory and variation characteristics of rock pore structure in water driving reservoirs, we have established a micropore-throat structure evolution model of core pore-throat characteristics. This fractal evolution model quantitatively characterized the complexity and evolution law of pore structure and clarified the relationship between fractal dimension of core pore structure and water cut under different stages of water driving.
Theoretical Analysis and Comparison of the Thermal Performance, Construction Costs, and Maintenance Complexity between a Conventional and an Intensive Green Roof
Authors: Brucker Juricic Belinda , Krstić Hrvoje , Čulo Ksenija
Published: June 2021

In this paper, a comparison between a conventional flat roof and an intensive green roof was made. Emphasis was on thermal conductivity of individual layers, the calculation of thermal resistance, and calculation of the thermal transmittance coefficient through both roof variants. The calculations for the two analysed roof variants were made for a building located in the town of Rijeka on the Adriatic coast. This paper also presents the construction technology comparison of the analysed roof variants. The construction cost was also analysed for both roof variants together with time needed for the execution of variant solutions. Finally, maintenance plans for both roof variants were presented in this paper. The results show that the construction costs of an intensive green roof are higher than the construction costs of a conventional flat roof and that the maintenance of the intensive green roof is more complex. On the other hand, the results of the analysis also show that constructing a green roof will result in more energy savings in the long term than in the case of constructing a conventional flat roof. In addition, there are several other benefits that go in favour of constructing an intensive green roof. Most prominent among those benefits are environmental and social benefits.
The Effect of Thermocycling on Interfacial Bonding Stability of Self‐Etch Adhesives: OCT Study
Authors: Bakhsh T. A. , Turkistani A.
Published: June 2021

Objective. The aim of this study was to monitor the behavior of interfacial gaps formed under different bonded polymeric restorations before and after thermocycling (TC), using swept‐source optical coherence tomography (SS‐OCT) and confirming the obtained findings with confocal laser scanning microscopy (CLSM). Materials and Methods. Cylindrical class I cavities were prepared in twenty noncarious human premolar teeth (1.5 mm depth × 3.5 mm diameter) and divided randomly into two groups: TS and SN, according to the adhesive system (n = 10). In the TS group, one‐step self‐etch adhesive Clearfil Tri‐S Bond Plus (Kuraray Noritake Dental, Japan) was used, followed by composite restoration using Estelite Sigma Quick (Tokuyama Dental, Japan). In the SN group, the cavities were restored with the two‐step self‐etch/composite silorane‐based resin restoration system (3M ESPE, USA). All specimens were restored in bulk filling technique and cured in accordance with the manufacturers’ instructions. Both groups were imaged under SS‐OCT after 24 h and recorded as controls. Then, each group was subjected to thermal challenge using the TC machine (5–55°C) and B‐scans were recorded at different TC intervals (2600, 5200, and 10000). In order to confirm the SS‐OCT findings, additional specimens were prepared, scanned, and sectioned for CLSM observation. Results. B‐scans demonstrated white clusters at the tooth‐resin interface that corresponded to the gap location on CLSM images. The TS group showed significantly less gap formation than the SN group before and after TC (p < 0.001). Conclusions. An optimal composite adaptation can be achieved when the bonded restoration comprises a combination of an adhesive containing 10‐MDP monomer and a considerable highly filled composite.
Design of Distributed Collection Model of Student Development Information Based on Internet of Things Technology
Authors: Ji Hui
Published: June 2021

This paper is aimed at the problem that the process of students’ developmental assessment is too comprehensive and the process of data collection is too old. It is very important but the performance of existing methods cannot meet the actual needs. So, this paper puts forward the design of distributed collection model of students’ developmental information based on Internet of Things technology, which is based on the hardware design of students’ developmental information distributed collection such as RF RC500F chip, TIMSP430 microprocessor, and interface in Internet of Things environment. Experimental results show that the model has less noise interference and strong data transmission ability, has higher collection accuracy of student development information, and can improve the authenticity and comprehensiveness of student development assessment.
Comprehensive Investigation of Solar-Based Hydrogen and Electricity Production in Iran
Authors: Kalbasi Rasool , Jahangiri Mehdi , Tahmasebi Ahmad
Published: June 2021

Hydrogen is a clean and environmentally friendly energy vector that can play an important role in meeting the world’s future energy needs. Therefore, a comprehensive study of the potential for hydrogen production from solar energy could greatly facilitate the transition to a hydrogen economy. Because by knowing the exact amount of potential for solar hydrogen production, the cost-effectiveness of its production can be compared with other methods of hydrogen production. Considering the above, it can be seen that so far no comprehensive study has been done on finding the exact potential of solar hydrogen production in different stations of Iran and finding the most suitable station. Therefore, in the present work, for the first time, using the HOMER and ArcGIS softwares, the technical-economic study of solar hydrogen production at home-scale was done. The results showed that Jask station with a levelized cost of energy equal to $ 0.172 and annual production of 83.8 kg of hydrogen is the best station and Darab station with a levelized cost of energy equal to $ 0.286 and annual production of 50.4 kg of hydrogen is the worst station. According to the results, other suitable stations were Bushehr and Deyr, and other unsuitable stations were Anzali and Khalkhal. Also, in 102 under study stations, 380 MW of solar electricity equivalent to 70.2 tons of hydrogen was produced annually. Based on the geographic information system map, it is clear that the southern half of Iran, especially the coasts of the Persian Gulf and the sea of Oman, is suitable for hydrogen production, and the northern, northeastern, northwestern, and one region in southern of Iran are unsuitable for hydrogen production. The authors of this article hope that the results of the present work will help the energy policymakers to create strategic frameworks and a roadmap for the production of solar hydrogen in Iran.