bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of the Autonomic Response in Alzheimer's Patients During the Execution of Memory Tasks: A Functional Thermal Imaging Study
Authors: Perpetuini David , Cardone Daniela , Bucco Roberta , Zito Michele , Merla Arcangelo
Published: May 2018

Background:

Alzheimer’s disease (AD) is a form of dementia characterized by failure of
memory that becomes more severe with the progression of the disease. The Free and Cued Selective
Reminding Test (FCSRT) is a clinical test used to evaluate such a deficit. However, since the cognitive
performances could depend also on the psychophysiological state of the individual, it is important to
monitor that state through the peripheral autonomic activity during the execution of the test. Thermal
infrared imaging has been used for this kind of assessment in order to preserve the free and unbiased
interaction between doctor and patient, thanks to the contactless features of the technique.

Objective:

To investigate whether the variation of facial temperature parameters during the FCSRT is
indicative of different autonomic states in the early AD with respect to healthy controls (HC).

Results:

At a group level, a greater sympathetic activity for the HC with respect to AD during the execution
of the test was found, indicative of a suppression of anxiety associated with the performances of the
FCSRT in AD patients.

Conclusion:

These results indicate that AD and HC may present different autonomic activity associated
with the execution of a cognitive task, thus suggesting a different modulation of high-cognition and
emotion network.
Research-Tested Mobile Apps for Breast Cancer Care: Systematic Review (Preprint)
Authors: Jongerius Chiara , Russo Selena , Mazzocco Ketti , Pravettoni Gabriella
Published: May 2018

BACKGROUND

The use of mobile health (mHealth) apps in clinical settings is increasing widely. mHealth has been used to promote prevention, improve early detection, manage care, and support survivors and chronic patients. However, data on the efficacy and utility of mHealth apps are limited.

OBJECTIVE

The main objective of this review was to provide an overview of the available research-tested interventions using mHealth apps and their impact on breast cancer care.

METHODS

A systematic search of Medline, PsycINFO, Embase, and Scopus was performed to identify relevant studies. From the selected studies, the following information was extracted: authors, publication date, study objectives, study population, study design, interventions’ features, outcome measures, and results.

RESULTS

We identified 29 empirical studies that described a health care intervention using an mHealth app in breast cancer care. Of these, 7 studies were about the use of an mHealth application in an intervention for breast cancer prevention and early detection, 12 targeted care management, and 10 focused on breast cancer survivors.

CONCLUSIONS

Our results indicate consistent and promising findings of interventions using mHealth apps that target care management in breast cancer. Among the categories of mHealth apps focusing on survivorship, mHealth-based interventions showed a positive effect by promoting weight loss, improving the quality of life, and decreasing stress. There is conflicting and less conclusive data on the effect of mHealth apps on psychological dimensions. We advocate further investigation to confirm and strengthen these findings. No consistent evidence for the impact of interventions using mHealth apps in breast cancer prevention and early detection was identified due to the limited number of studies identified by our search. Future research should continue to explore the impact of mHealth apps on breast cancer care to build on these initial recommendations.
Digital Interventions to Reduce Sedentary Behaviors of Office Workers: Scoping Review (Preprint)
Authors: Huang Yitong , Benford Steve , Blake Holly
Published: May 2018

BACKGROUND

There is a clear public health need to reduce office workers’ sedentary behaviors (SBs), especially in the workplace. Digital technologies are increasingly being deployed in the workplace to measure and modify office workers’ SBs. However, knowledge of the range and nature of research on this topic is limited; it also remains unclear to what extent digital interventions have exploited the technological possibilities.

OBJECTIVE

This study aimed to investigate the technological landscape of digital interventions for SB reduction in office workers and to map the research activity in this field.

METHODS

Terms related to SB, office worker, and digital technology were applied in various combinations to search Cochrane Library, Joanna Briggs Institute Database of Systematic Reviews, MEDLINE, PsycARTICLES, PsycINFO, Scopus, Association for Computing Machinery Digital Library, Engineering index Compendex, and Google Scholar for the years 2000 to 2017. Data regarding the study and intervention details were extracted. Interventions and studies were categorized into development, feasibility and/piloting, evaluation, or implementation phase based on the UK Medical Research Council (MRC) framework for developing and evaluating complex interventions. A novel framework was developed to classify technological features and annotate technological configurations. A mix of quantitative and qualitative approaches was used to summarize data.

RESULTS

We identified 68 articles describing 45 digital interventions designed to intervene with office workers’ SB. A total of 6 common technological features had been applied to interventions with various combinations. Configurations such as “information delivery and mediated organizational and social support” and “digital log and automated tailored feedback” were well established in evaluation and implementation studies; in contrast, the integration of passive data collection, connected devices, and ATF or scheduled prompts was mostly present in development and piloting research.

CONCLUSIONS

This review is the first to map and describe the use of digital technologies in research on SB reduction in office workers. Interdisciplinary collaborations can help to maximize the potential of technologies. As novel modes of delivery that capitalize on embedded computing and electronics, wireless technologies have been developed and piloted in engineering, computing, and design fields, efforts can be directed to move them to the next phase of evaluation with more rigorous study designs. Quality of research may be improved by fostering conversations between different research communities and encouraging researchers to plan, conduct, and report their research under the MRC framework. This review will be particularly informative to those deciding on areas where further research or development is needed and to those looking to locate the relevant expertise, resources, and design inputs when designing their own systems or interventions.
Association Between Advanced Care Management and Progression of Care Needs Level in Long-Term Care Recipients: Retrospective Cohort Study (Preprint)
Authors: Itoh Sakiko , Hikichi Hiroyuki , Murayama Hiroshi , Ishimaru Miho , Ogata Yasuko , Yasunaga Hideo
Published: May 2018

BACKGROUND

Long-term care insurance systems in Japan started a special senior care program overseen by qualified care managers (also known as advanced care managers). However, the relationship between advanced care management and outcomes in long-term care recipients remains unknown.

OBJECTIVE

We aimed to compare the outcome of long-term care recipients using facilities with advanced care management and conventional care management, in terms of care needs level progression.

METHODS

We conducted a retrospective cohort study using the Survey of Long-Term Care Benefit Expenditures in Japan. We identified those aged ≥65 years who were newly designated a care need level of 3, and received long-term care services between April 2009 and March 2014 in Tokyo. We compared survival without progression of care needs level between the groups, with and without advanced care management, using the Kaplan-Meier method. Factors affecting the outcomes were determined using a multivariable logistic regression model fitted with a generalized estimating equation.

RESULTS

Of 45,330 eligible persons, 12,903 (28.46%) received long-term care based on advanced care management. The average duration of progression-free survival was 17.4 (SD 10.2) months. The proportions of five-year cumulative progression-free survival were 41.2% and 32.8% in those with and without advanced care management, respectively. The group with advanced care management had significantly lower care needs levels (odds ratio 0.77, 95% CI, 0.72-0.82, P<.001).

CONCLUSIONS

Advanced care management was significantly associated with improved care needs levels.
Simulated Clinical Encounters Using Patient-Operated mHealth: Experimental Study to Investigate Patient-Provider Communication (Preprint)
Authors: Tunnell Harry , Faiola Anthony , Bolchini Davide , Bartlett Ellis Rebecca
Published: May 2018

BACKGROUND

This study investigates patient-centered mobile health (mHealth) technology in terms of the secondary user experience (UX). Specifically, it examines how personal mobile technology, under patient control, can be used to improve patient-provider communication about the patient’s health care during their first visit to a provider. Common ground, a theory about language use, is used as the theoretical basis to examine interactions. A novel concept of this study is that it is one of the first empirical studies to explore the relative meaningfulness of a secondary UX for specific health care tasks.

OBJECTIVE

The objective of this study was to investigate the extent that patient-operated mHealth technology can be designed to improve the communication between the patient and provider during an initial face-to-face encounter.

METHODS

The experimental study was conducted in 2 large Midwestern cities from February 2016 to May 2016. A custom-designed smartphone app prototype was used as the study treatment. The experimental design was posttest-only control group and included video-recorded simulated face-to-face clinical encounters in which an actor role-played a patient. Experienced clinicians consisting of doctors (n=4) and nurses (n=8) were the study participants. A thematic analysis of qualitative data was performed. Quantitative data collected from time on task measurements were analyzed using descriptive statistics.

RESULTS

Three themes that represent how grounding manifested during the encounter, what it meant for communication during the encounter, and how it influenced the provider’s perception of the patient emerged from the qualitative analysis. The descriptive statistics were important for inferring evidence of efficiency and effectiveness of communication for providers. Overall, encounter and task times averaged slightly faster in almost every instance for the treatment group than that in the control group. Common ground clearly was better in the treatment group, indicating that the idea of designing for the secondary UX to improve provider outcomes has merit.

CONCLUSIONS

Combining the notions of common ground, human-computer interaction design, and smartphone technology resulted in a prototype that improved the efficiency and effectiveness of face-to-face collaboration for secondary users. The experimental study is one of the first studies to demonstrate that an investment in the secondary UX for high payoff tasks has value but that not all secondary UXs are meaningful for design. This observation is useful for prioritizing how resources should be applied when considering the secondary UX.
The Continuing Value of CD4 Cell Count Monitoring for Differential HIV Care and Surveillance (Preprint)
Authors: Rice Brian , Boulle Andrew , Schwarcz Sandra , Shroufi Amir , Rutherford George , Hargreaves James
Published: May 2018

UNSTRUCTURED

The move toward universal provision of antiretroviral therapy and the expansion of HIV viral load monitoring call into question the ongoing value of CD4 cell count testing and monitoring. We highlight the role CD4 monitoring continues to have in guiding clinical decisions and measuring and evaluating the epidemiology of HIV. To end the HIV/AIDS epidemic, we require strategic information, which includes CD4 cell counts, to make informed clinical decisions and effectively monitor key surveillance indicators.
Automatic Classification of Online Doctor Reviews: Evaluation of Text Classifier Algorithms (Preprint)
Authors: Rivas Ryan , Montazeri Niloofar , Le Nhat XT , Hristidis Vagelis
Published: May 2018

BACKGROUND

An increasing number of doctor reviews are being generated by patients on the internet. These reviews address a diverse set of topics (features), including wait time, office staff, doctor’s skills, and bedside manners. Most previous work on automatic analysis of Web-based customer reviews assumes that (1) product features are described unambiguously by a small number of keywords, for example, battery for phones and (2) the opinion for each feature has a positive or negative sentiment. However, in the domain of doctor reviews, this setting is too restrictive: a feature such as visit duration for doctor reviews may be expressed in many ways and does not necessarily have a positive or negative sentiment.

OBJECTIVE

This study aimed to adapt existing and propose novel text classification methods on the domain of doctor reviews. These methods are evaluated on their accuracy to classify a diverse set of doctor review features.

METHODS

We first manually examined a large number of reviews to extract a set of features that are frequently mentioned in the reviews. Then we proposed a new algorithm that goes beyond bag-of-words or deep learning classification techniques by leveraging natural language processing (NLP) tools. Specifically, our algorithm automatically extracts dependency tree patterns and uses them to classify review sentences.

RESULTS

We evaluated several state-of-the-art text classification algorithms as well as our dependency tree–based classifier algorithm on a real-world doctor review dataset. We showed that methods using deep learning or NLP techniques tend to outperform traditional bag-of-words methods. In our experiments, the 2 best methods used NLP techniques; on average, our proposed classifier performed 2.19% better than an existing NLP-based method, but many of its predictions of specific opinions were incorrect.

CONCLUSIONS

We conclude that it is feasible to classify doctor reviews. Automatically classifying these reviews would allow patients to easily search for doctors based on their personal preference criteria.
The Impact of the eHealth Technologies on the Chronically-ill Patient�s choice of Same Hospital Again (Preprint)
Authors: Li Zhendong , Zhang Huiying , Jiang Ke , Wei Wei , Mainstone Mitchell
Published: May 2018

BACKGROUND

The rapidly-increasing numbers representing China’s ageing population necessarily results in increased medical expenditure following the needs of elderly people, particularly patients with chronic diseases. However, China’s healthcare system is struggling with this as a major issue: famous public hospitals are overcrowded, while community and rural hospitals find it difficult to attract enough patients.

OBJECTIVE

To examine how and whether the application of eHealth technologies in medical field influences chronically ill patients’ choice of same hospital on next visit.

METHODS

From July to October 2016, we conducted a survey in nine hospitals in Northern China. This study used regression analysis to compare the difference between high and low levels of application of eHealth technologies in the medical field. We constructed a hospital choice model in order to assist with this. According to the model, we analysed the relationship between relevant, influential factors and the chronically-ill patient’s choice of same hospital on next visit.

RESULTS

Empirical findings suggest that the chronically-ill patient’s choice of hospital on next visit is positively affected by the treatment level (β= 0.682, P < 0.001) and level of hospital convenience (β= 0.311, P < 0.001), and negatively affected by the medical costs (β= -0.124, P < 0.001). Additionally, Our findings suggest that the application of eHealth technologies in the medical field can significantly enhance the positive correlation between level of hospital convenience and the chronically-ill patients’ choice of same hospital on next visit (β= 0.269, P < 0.001), as well as the negative correlation between medical costs incurred and the chronically-ill patients’ choice of same hospital on next visit (β= -0.135, P < 0.001) . By contrast, the application of eHealth technologies weakens the positive correlation between the hospital’s treatment level and chronically-ill patients’ choice of same hospital on next visit (β= -0.241, P < 0.001).

CONCLUSIONS

The introduction of the eHealth technologies significantly closes the gap between levels of treatment provided by differing hospitals, while prompting hospital to improve the level of convenience for patients with chronic disease, as well as reducing any medical expense incurred.

CLINICALTRIAL

This study protocol was approved by the Ethics Committee of Tianjin University of Traditional Chinese Medicine. The reference number is TJUTCM-EC20160005.
Web-Based Self-Management Programs for Bipolar Disorder: Insights From the Online, Recovery-Oriented Bipolar Individualised Tool Project (Preprint)
Authors: Fletcher Kathryn , Foley Fiona , Murray Greg
Published: May 2018

BACKGROUND

Bipolar disorder (BD) is a complex, relapsing mood disorder characterized by considerable morbidity and mortality. Web-based self-management interventions provide marked opportunities for several chronic mental health conditions. However, Web-based self-management programs targeting BD are underrepresented compared with programs targeting other psychiatric conditions.

OBJECTIVE

This paper aims at facilitating future research in the area of self-management of BD and draws insights from the development of one such intervention—the Online, Recovery-Oriented Bipolar Individualised Tool (ORBIT)—that is aimed at improving the quality of life of people with BD.

METHODS

We have discussed the opportunities and challenges in developing an engaging, evidence-based, safe intervention within the context of the following three nested domains: (1) intervention development; (2) scientific testing of the intervention; and (3) ethical framework including risk management.

RESULTS

We gained the following insights across the three abovementioned overlapping domains: Web-based interventions can be optimized through (1) codesign with consumers with lived experience to ensure relevance and appropriateness to the target audience; (2) novel content development processes that iteratively combine evidence-based information with lived experience perspectives, capitalizing on multimedia (eg, videos) that the digital health space provides; and (3) incorporating Web-based communities to connect end users and promote constructive engagement by access to a Web-based coach.

CONCLUSIONS

Self-management is effective in BD, even for those on the more severe end of the spectrum. While there are challenges to be aware of, guided self-management programs, such as those offered by the ORBIT project, which are specifically developed for Web-based delivery provide highly accessible, engaging, and potentially provocative treatments for chronically ill populations who may otherwise have never engaged with treatment. Key questions about engagement, effectiveness, and cost-effectiveness will be answered by the ORBIT project over the next 18 months.
Implementation of an Integrated Community-Based Dental Care System for Low Income Children: Initial Findings (Preprint)
Authors: Cunha-Cruz Joana , Huebner Colleen E. , Ludwig Sharity , Conrad Douglas A. , Dysert Jeanne , Mitchell Melissa , Allen Gary , Shirtcliff R. Michael , Spiekerman Charles , Bailit Howard L. , Milgrom Peter
Published: May 2018

BACKGROUND

To improve access to care and reduce disparities in oral health of low-income children and pregnant women, this quality improvement program used expanded practice dental hygienists, provided an evidence-based risk assessment and dental caries management protocol-based care in community settings, and paid personnel based on performance. A health information technology system was implemented integrating community-based practice, case management, and clinic records.

OBJECTIVE

Our objective was to describe the first year of implementation of the program including the processes, services provided, and factors that helped and hindered these implementation efforts.

METHODS

The mobile integrated community-based delivery system (PREDICT) was implemented as a quality improvement project within a large Dental Care Organization (DCO) that includes fixed dental clinics and contracted practices. The program is being tested in a randomized controlled trial. The target populations were Medicaid-eligible children and pregnant women in 7 rural counties in Oregon State USA. Data were collected from staff and community surveys, interviews, and administrative and dental health records.

RESULTS

Baseline assessments indicated patient satisfaction with care and staff readiness to implement changes were high. In PREDICT counties 9 expanded practice dental hygienists provided 37,369 services - an average of 4,152 services per EPDH in 198 community sites. Utilization ranged from 33-63% of eligible children and 30-42% of women, respectively, by county. For patients with ≥1 visits, 42% received a needs assessment, 88% preventive services and 26% restorative or endodontic services. By dental care need levels, 34% were low, 30% moderate, 32% high and 4% were not assigned to a group. Among moderate-need group, 51% received 1 silver diamine fluoride application and 19% two applications. Within the high-need group referred to dental clinics, 11% had urgent needs, 56% non-urgent needs, and the remaining 33% had non-urgent needs that could be treated in community settings. About 51% of the high-need group referred to dental clinics received services.

CONCLUSIONS

Initial findings confirm the strong emphasis of the program on access and use of preventive services, and the varying degrees of program reach in different counties. Implementation challenges in communities at different stages of collaboration between the dental care, school, and other community organizations limited the achievement of the audacious goals of the program in its first year.

CLINICALTRIAL

ClinicalTrials.gov Identifier: NCT02312921
Acceptability of Continuous Glucose Monitoring in Free-Living Healthy Individuals: Implications for the Use of Wearable Biosensors in Diet and Physical Activity Research (Preprint)
Authors: Liao Yue , Schembre Susan
Published: May 2018

BACKGROUND

Wearable sensors have been increasingly used in behavioral research for real-time assessment and intervention purposes. The rapid advancement of biomedical technology typically used in clinical settings has made wearable sensors more accessible to a wider population. Yet the acceptability of this technology for nonclinical purposes has not been examined.

OBJECTIVE

The aim was to assess the acceptability of wearing a continuous glucose monitor (CGM) device among a sample of nondiabetic individuals, and to compare the acceptability of a CGM between a mobile diet tracking app (MyFitnessPal) and an accelerometer.

METHODS

A total of 30 nondiabetic adults went through a 7-day observational study. They wore a CGM sensor, tracked their diet and physical activity using the CGM receiver and MyFitnessPal, and wore an accelerometer on their waist. After the monitoring period, they completed a 10-item survey regarding acceptability of each of the study tools. Two-tailed paired-sample t tests were conducted to examine whether the summary acceptability scores were comparable between the CGM sensor/receiver and MyFitnessPal/accelerometer.

RESULTS

More than 90% of the study participants agreed that the CGM sensor and receiver were easy to use (28/30 and 27/30, respectively), useful (28/30 and 29/30, respectively), and provided relevant information that was of interest to them (27/30 and 28/30, respectively). The summary acceptability scores (out of a 5-point Likert scale) were mean 4.06 (SD 0.55) for the CGM sensor, mean 4.05 (SD 0.58) for the CGM receiver, mean 4.10 (SD 0.68) for MyFitnessPal, and mean 3.73 (SD 0.76) for the accelerometer.

CONCLUSIONS

The high acceptability of using a CGM from this study suggests a great potential for using CGMs in nondiabetic adults in research settings. Although potential selection bias might contribute to the high acceptability in this study, the continued advancements in wearable sensor technology will make the barriers to tracking and collecting personal physiological data more and more minimal.
The Impact of a Web-Based Course Concerning Patient Education for Mental Health Care Professionals: Quasi-Experimental Study (Preprint)
Authors: Laine Anna , Välimäki Maritta , Löyttyniemi Eliisa , Pekurinen Virve , Marttunen Mauri , Anttila Minna
Published: May 2018

BACKGROUND

Continuing education has an important role in supporting the competence of health care professionals. Although Web-based education is a growing business in various health sectors, few studies have been conducted in psychiatric settings to show its suitability in demanding work environments.

OBJECTIVE

We aimed to describe the impact of a Web-based educational course to increase self-efficacy, self-esteem, and team climate of health care professionals. Possible advantages and disadvantages of the Web-based course are also described.

METHODS

The study used nonrandomized, pre-post intervention design in 1 psychiatric hospital (3 wards). Health care professionals (n=33) were recruited. Self-efficacy, self-esteem, and team climate were measured at 3 assessment points (baseline, 8 weeks, and 6 months). Possible advantages and disadvantages were gathered with open-ended questions at the end of the course.

RESULTS

Our results of this nonrandomized, pre-post intervention study showed that health care professionals (n=33) had higher self-efficacy after the course, and the difference was statistically significant (mean 30.16, SD 3.31 vs mean 31.77, SD 3.35; P=.02). On the other hand, no differences were found in the self-esteem or team climate of the health care professionals before and after the course. Health care professionals found the Web-based course useful in supporting their work and relationships with patients. The tight schedule of the Web-based course and challenges in recruiting patients to use the patient education program with health care professionals were found to be the disadvantages.

CONCLUSIONS

Web-based education might be a useful tool to improve the self-efficacy of health care professionals even in demanding work environments such as psychiatric hospitals. However, more studies with robust and sufficiently powered data are still needed.
Identifying Outcomes that Are Important to Living Kidney Donors
Authors: Hanson Camilla S. , Chapman Jeremy R. , Gill John S. , Kanellis John , Wong Germaine , Craig Jonathan C. , Teixeira-Pinto Armando , Chadban Steve J. , Garg Amit X. , Ralph Angelique F. , Pinter Jule , Lewis Joshua R. , Tong Allison
Published: May 2018

Background and objectives

Living kidney donor candidates accept a range of risks and benefits when they decide to proceed with nephrectomy. Informed consent around this decision assumes they receive reliable data about outcomes they regard as critical to their decision making. We identified the outcomes most important to living kidney donors and described the reasons for their choices.

Design, setting, participants, & measurements

Previous donors were purposively sampled from three transplant units in Australia (Sydney and Melbourne) and Canada (Vancouver). In focus groups using the nominal group technique, participants identified outcomes of donation, ranked them in order of importance, and discussed the reasons for their preferences. An importance score was calculated for each outcome. Qualitative data were analyzed thematically.

Results

Across 14 groups, 123 donors aged 27–78 years identified 35 outcomes. Across all participants, the ten highest ranked outcomes were kidney function (importance=0.40, scale 0–1), time to recovery (0.27), surgical complications (0.24), effect on family (0.22), donor-recipient relationship (0.21), life satisfaction (0.18), lifestyle restrictions (0.18), kidney failure (0.14), mortality (0.13), and acute pain/discomfort (0.12). Kidney function and kidney failure were more important to Canadian participants, compared with Australian donors. The themes identified included worthwhile sacrifice, insignificance of risks and harms, confidence and empowerment, unfulfilled expectations, and heightened susceptibility.

Conclusions

Living kidney donors prioritized a range of outcomes, with the most important being kidney health and the surgical, lifestyle, functional, and psychosocial effects of donation. Donors also valued improvements to their family life and donor-recipient relationship. There were clear regional differences in the rankings.
Characterization and expression analysis of growth regulating factor (GRF) family genes in cucumber
Authors: Zhou Yong , Ge Lingli , Li Guanghua , Jiang Lunwei , Yang Yingui
Published: May 2018

The growth regulating factor (GRF) family is a conserved class of transcription factors involved in various biological processes in plants. However, there have been only a few studies of the GRF family genes in cucumber, Cucumis sativus (Cs). In this study, we identified and characterized 8 CsGRF genes in cucumber. Two highly conserved domains, QLQ and WRC, were identified to be present in all CsGRF proteins. In addition, three less conserved domains (FFD, TQL, and GGPL) were also detected in some CsGRF members. Based on phylogenetic analysis, the GRF genes from cucumber, Arabidopsis, tomato, rice and maize could be classified into 10 groups, and CsGRFs were clustered closer with the GRF genes from dicots (Arabidopsis and tomato) than with those from monocots (rice and maize). Promoter analysis revealed that the CsGRF genes were involved in cucumber growth and development as well as in responses to various hormones and stresses. Transcriptome data showed that the CsGRF genes have distinct expression patterns in different tissues, especially in ovaries and leaves. Expression profiling analysis indicated that all CsGRF genes were responsive to salt and drought stress treatments. These results demonstrate that the cucumber GRF gene family may function in organ development and plant stress responses.
Fluid dynamics assessment of the Tesla turbine rotor
Authors: Manfrida Giampaolo , Talluri Lorenzo
Published: May 2018

The Tesla turbine seems to offer several points of attractiveness when applied to low-power applications. Indeed, it is a simple, reliable, and low cost machine. The principle of operation of the turbine relies on the exchange of momentum due to the shear forces originated by the flow of the fluid through a tight gap among closely stacked disks. This turbine was firstly developed by Tesla at the beginning of the 20th century, but it did not stir up much attention due to the strong drive towards large centralized power plants, on the other hand, in recent years, as micro power generation gained attention on the energy market place, this original expander raised renewed interest. The mathematical model of the Tesla turbine rotor is revised, and adapted to real gas operation. The model is first validated by comparison with other assessed literature models. The optimal configuration of the rotor geometry is then investigated running a parametric analysis of the fundamental design parameters. High values of efficiency (isolated rotor) were obtained for the optimal configuration of the turbine, which appears interesting for small-scale power generation. The rotor efficiency depends on the configuration of the disks, particularly on the gap and on the outlet diameter, which determines largely the kinetic energy at discharge.
Experimental and numerical investigation of thermal and fluid-flow processes in a matrix heat exchanger
Authors: Tomic Mladen , Zivkovic Predrag , Milutinovic Biljana , Vukic Mica , Andjelkovic Aleksandar
Published: May 2018

The need for compact heat exchangers has led to the development of many types of surfaces that enhance the rate of heat transfer, among them the matrix heat exchangers. These heat exchangers consist of a series of perforated plates mutually separated and sealed by spacers. The goal of this research was to investigate the heat transfer process of matrix heat exchangers on the air side, at the close to ambient conditions. The research was conducted in two directions ? experimental research and CFD research. The experimental investigation was carried out over a perforated plate package with the porosity of 25.6%. The air/water matrix heat exchanger was heated by hot water and was installed in an experimental chamber at which entrance was a fan with the variable flow rate and heated by hot water. The thermocouples were attached to the surface of the perforated plate at the upwind and downwind sides, as well as at the inlet and the outlet of the chamber. During each experiment, the thermocouple readings and the air and water-flow and temperatures were recorded. In the numerical part of the research, the matrix heat exchangers with different plate porosity from 10 to 50% were investigated. The results of the numerical simulations were validated against the experimental results. On the basis of the experimental and numerical results, equations for heat transfer as the function of Reynolds number and geometrical parameters was established.
Estimation of photovoltaic power generation potential in Serbia based on irradiance, air temperature, and wind speed data
Authors: Doljak Dejan , Stanojevic Gorica , Radovanovic Milan , Malinovic-Milicevic Slavica
Published: May 2018

This study is devoted to the research of spatial-temporal variation of electricity generation from the kilowatt-peak photovoltaic system made of crystalline silicon solar cells. The research was conducted in the territory of Serbia using the model for estimation photovoltaic performances as a function of incident irradiance and module temperature. Preparation of input data and calculation of the final results was done within the geographical information system. Some of the required raster data, like solar irradiance and wind speed, were already available, while air temperature raster was created from discrete set of observed data using the regression-kriging model. Obtained results were presented in the form of raster maps that enabled further analysis and discussion about new findings. The analysis of seasonal variations reveals that during spring and summer months photovoltaic systems are producing up to 70% of total annual electricity yield. In terms of the spatial distribution, the most promising areas for electricity generation are located in the south part of Serbia and along main river valleys. In addition, discussion part addresses the issue of data imperfection caused by the accuracy of the selected model, as well as quality and availability of data series.
Renewable electricity in Western Balkans: Support policies and current state
Authors: Rakic Nikola , Gordic Dusan , Sustersic Vanja , Josijevic Mladen , Babic Milun
Published: May 2018

The use of renewable energy sources for electricity generation in the Western Balkan countries is analyzed in this review paper. Since those countries are part of EU or intend to be, data for Western Balkan are also compared with data for EU-28. The first part of the paper presents a brief overview of main promotion mechanism for electricity generation from renewable energy sources. As a dominant support policy, the feed-in tariff is more elaborated as an incentive measure and a de?tailed overview of the amount of tariffs and quotas for dominant technologies in the Western Balkan countries is presented. Furthermore, the current state of installed capacities and annual productions of three particular renewable electricity technologies (small hydro power, wind power, and solar photovoltaic) are analyzed in detailes. Based on presented data, there is a discussion and consideration of the impact of incentive measures on the electricity market and power production from renewable sources.
Pathophysiological Characteristics Underlying Different Glucose Response Curves: A Latent Class Trajectory Analysis From the Prospective EGIR-RISC Study
Authors: Hulman Adam , Witte Daniel R. , Vistisen Dorte , Balkau Beverley , Dekker Jacqueline M. , Herder Christian , Hatunic Mensud , Konrad Thomas , Færch Kristine , Manco Melania
Published: May 2018

OBJECTIVE

Glucose measurements during an oral glucose tolerance test (OGTT) are useful in predicting diabetes and its complications. However, knowledge of the pathophysiology underlying differences in glucose curve shapes is sparse. We examined the pathophysiological characteristics that create different glucose curve patterns and studied their stability and reproducibility over 3 years of follow-up.

RESEARCH DESIGN AND METHODS

We analyzed data from participants without diabetes from the observational cohort from the European Group for the Study of Insulin Resistance: Relationship between Insulin Sensitivity and Cardiovascular Disease study; participants had a five–time point OGTT at baseline (n = 1,443) and after 3 years (n = 1,045). Measures of insulin sensitivity and secretion were assessed at baseline with a euglycemic-hyperinsulinemic clamp and intravenous glucose tolerance test. Heterogeneous glucose response patterns during the OGTT were identified using latent class trajectory analysis at baseline and at follow-up. Transitions between classes were analyzed with multinomial logistic regression models.

RESULTS

We identified four different glucose response patterns, which differed with regard to insulin sensitivity and acute insulin response, obesity, and plasma levels of lipids and inflammatory markers. Some of these associations were confirmed prospectively. Time to glucose peak was driven mainly by insulin sensitivity, whereas glucose peak size was related to both insulin sensitivity and secretion. The glucose patterns identified at follow-up were similar to those at baseline, suggesting that the latent class method is robust. We integrated our classification model into an easy-to-use online application that facilitates the assessment of glucose curve patterns for other studies.

CONCLUSIONS

The latent class analysis approach is a pathophysiologically insightful way to classify individuals without diabetes based on their response to glucose during an OGTT.
DAERAH RAWAN BENCANA GEOLOGI GERAKAN TANAH DALAM ARAHAN KEBIJAKAN MITIGASI KABUPATEN CIAMIS
Authors: Rosita Aris , Aryanto Deasy , Noorainy Fitria , Slamet Memet , Permadi Dwiyana
Published: May 2018

Gerakan tanah seringkali menimbulkan bencana pada daerah permukiman dan bahkan  menimbulkan korban jiwa. Gerakan tanah sering terjadi pada daerah dengan gugus vulkano muda seperti di daerah Jawa Barat terutama di Wilayah Ciamis pada kelerengan yang curam. Kesiapsiagaan ini tentunya harus di siapkan secara menyeluruh bergantung pada kerentanan kejadian gerakan tanah dan juga waktu terjadinya bencana yang pada umumnya terjadi pada musim hujan setelah masa kering yang ekstrim melebihi seratus hari. Tulisan ini mencoba membahas sisi kebijakan dan akademik yang perlu disiapkan dalam menghadapi bencana pada BNPB Kabupaten Ciamis dari berbagai kejadian gerakan tanah yang terjadi daerah Nasol Kabupaten Ciamis. Melalui studi penelusuran dokumen dan kepustakaan sebagai metoda yang digunakan dalam membahas konsep dan strategi penanganan bencana gerakan tanah ini, kami memaparkan hal penting yang perlu dicermati dalam kebijakan pemerintah Kabupaten Ciamis. hasil yang diperoleh adalah secara empirik gerakan tanah di daerah Nasol menunjukan kerusakan yang tinggi pada daerah permukiman, kelerengan dan sangat membahayakan permukiman menempati di kelerengan lebih rendah. Keadaan ini harus terinformasikan dengan baik kepada masyarakat dan arahan mitigasi bencana yang diperlukan dalam penanganannya. Disisi lain adalah konsep BNPB harus dapat menentukan prioritas dari semua kejadian bencana di Kabupaten Ciamis adalah gerakan tanah merupakan ancaman terdepan pada saat pergantian musim.
KESIAPSIAGAAN MASYARAKAT KAWASAN PERKOTAAN TERHADAP BENCANA GEMPA BUMI
Authors: Arif Muhammad
Published: May 2018

Kawasan Perkotaan Takengon merupakan pusat kegiatan wilayah Kabupaten Aceh Tengah yang tidak lepas dari ancaman gempa bumi, sehingga memerlukan upaya penanggulangan, penelitian ini bertujuan mengetahui kesiapsiagaan masyarakat Kawasan Perkotaan Takengon dalam menghadapi bahaya bencana gempa bumi yang digambarkan melalui sikap dan perilaku masyarakat terhadap ancaman bencana. Metoda yang digunakan dalam penelitian ini yaitu metode penelitian campuran secara kualitatif dan kuantitatif dengan cara merumuskan faktor dan sub-faktor yang berpengaruh terhadap tingkat kesiapsiagaan masyarakat dalam menghadapi bahaya bencana gempa bumi. Hasil penelitian ini bahwa kesiapsiagaan masyarakat Kawasan Perkotaan Takengon dalam menghadapi bahaya bencana gempa bumi berada dalam kondisi cukup siap jika dilihat dari parameter pengetahuan dan sikap, kebijakan dan panduan, rencana tanggap darurat, sistem peringatan bencana, mobilisasi sumber daya dan modal sosial. Cukup siapnya masyarakat dalam menghadapi ancaman bencana ini antara lain disebabkan masyarakat belum mengetahui peraturan daerah menangani kesiapsiagaan untuk mengantisipasi bencana gempa bumi serta masih kurangnya panduan dalam menghadapi bencana gempa bumi jika bencana gempa bumi terjadi. Sementara itu belum banyak upaya peningkatan kesiapsiagaan bencana yang dilakukan oleh pemerintah karena terbatasnya sumber daya. Namun demikian, kondisi kesiapsiagaan masyarakat Kawasan Perkotaan Takengon dalam menghadapi bahaya bencana gempa bumi ini masih dapat ditingkatkan sehingga risiko yang terjadi dapat ditekan.
Páginas preliminares
Authors: EIA Revista
Published: May 2018

Páginas preliminares / volumen 15 / número 29
Estimación de la repetibilidad y factores que afectan el peso al nacer y al destete en ganado bovino cebú brahman
Authors: MONTES-V DONICER , VERGARA-G OSCAR , PRIETO-M ESPERANZA , BARRAGÁN-H WILSON
Published: May 2018

Con el objeto de obtener estimativos de repetibilidad para peso al nacer y al destete en ganado cebù Brahman y los factores que influyen sobre éstos, se analizaron 432 datos provenientes de 140 vacas registrados durante los años 2001 hasta 2007 de la empresa ganadera Inversiones Mundo Nuevo, Municipio de San Onofre (Sucre-Colombia). Usando modelos mixtos, se obtuvieron los componentes de varianza entre y dentro de vaca con los cuales se calculo la repetibilidad de las características en estudio. En el análisis de varianza se consideraron los efectos época (nacimiento o destete), año (nacimiento o destete), orden de partos y sexo del becerro. La media general para el peso al nacer fue de 35 ± 3 kg con coeficiente de variación de 9%. Las fuentes de variación consideradas en el modelo resultaron no significativas para peso al nacer. La media para el peso al destete fue 241 ± 30, con coeficiente de variación de 13 %, resultando significativo sobre esta variable el efecto de año, y no significativo los efectos de sexo, época y orden de parto. Los estimativos de repetibilidad fueron 0,11 + 0,05 y 0,19 + 0,04 para peso al nacer y al destete, respectivamente.
Diversidad de bacterias totales y endófitas asociadas a raíces del pasto bothriochloa pertusa (l) a. Camus
Authors: PEREZ C ALEXANDER. , ROJAS S JOHANNA , FUENTES C JUSTO
Published: May 2018

El objetivo del presente trabajo fue determinar la diversidad de comunidades cultivables de bacterias totales y endófitas asociadas a raíces del pasto colosuana en el departamento de Sucre. La diversidad de comunidades de bacterias totales y endófitas fue realizada mediante aislamiento de colonias en medios de cultivos (SAKIYAMA et al., 2001). La densidad poblacional fue estimada por conteo directo de colonias en placa y las características culturales de cada morfotipo fueron obtenidas mediante observación de cada colonia formada. Una vez cuantificadas las comunidades de bacterias totales y endófitas, se determinó la riqueza de especie (R), el índice de diversidad de ShannonWeaver (H) y la equitabilidad de morfotipos mediante modelos matemáticos propuestos para cada fin. Para establecer diferencias estadísticas entre comunidades de bacterias totales y endófitas se realizaron ANOVAS, test paramétricos y no paramétricos utilizando el programa R. Fueron muestreadas 14 fincas ganaderas, localizadas en la región fisiográfica de Sabanas de Sucre, donde fue reportada la presencia por primera vez de bacterias endófitas asociadas a las raíces de colosuana. Fueron encontradas diferencias significativas entre la riqueza de especies y la equitabilidad de bacterias totales y endófitas en raíces del pasto. Este es el primer reporte que se tiene sobre la presencia de bacterias endófitas en la raíces de este pasto a nivel mundial.
Estudio de caso: un sistema de producción silvopastoril con enfoque agroecológico, departamento del magdalena, Colombia
Authors: BOTERO LUZ , DE LA OSSA, V. JAIME
Published: May 2018

El presente documento corresponde a un estudio de caso de un sistema silvopastoril localizado en la finca la Florida, municipio de Santa Bárbara de Pinto, departamento del Magdalena, región Caribe colombiana. Se realizaron entrevistas abiertas y semiestructuradas a los trabajadores y al dueño de la finca, así como un recorrido por los diferentes potreros con el objetivo de caracterizar el agroecosistema donde se maneja el sistema silvopastoril. Se analizó la base de datos de producción para conocer el impacto del sistema sobre la producción animal, encontrándose que durante 20 años han manejado la sucesión vegetal a partir del banco de semillas del suelo y a través de estrategias como el pastoreo rotacional, el desmonte racional con machete y el control de arvenses selectivo, con bombas espalderas o arranque manual, permitiendo el establecimiento de una comunidad vegetal de tres estratos arbóreos, compartidos con gramíneas y algunas leguminosas rastreras nativas, para obtener de este arreglo espacial servicios ambientales e incrementar la biomasa forrajera.
Avances en el manejo integrado de la bacteria burkholderia glumae en el cultivo de arroz en el caribe colombiano
Authors: PEREZ C CRISTO , SAAVEDRA ENRIQUE
Published: May 2018

El presente trabajo tuvo como objetivo mostrar avances en el manejo integrado de la bacteria Burkholderia glumae, causante de la enfermedad del añublo bacterial de la panícula en el cultivo de arroz en el Caribe Colombiano a partir de estudios realizados en los 5 últimos años por Fedearroz-Fondo Nacional del arroz. Teniendo en cuenta las apreciaciones anteriores se enfatizó en la necesidad de implementar y aplicar unas estrategias de manejo integrado del añublo bacterial para la zona Caribe
Un sueño hecho realidad
Authors: DE LA OSSA V JAIME
Published: May 2018

Desde hacía algunos años una idea rondaba los claustros de la Facultad de Ciencias Agropecuarias de la Universidad de Sucre, recorría las mentes inquietas de los docentes de mayor claridad universal, comprometidos con su labor de maestros, dedicados no solo a exponer sus clases, sino preocupados por el destino de sus discípulos y su claustro, de su valiosa sapiencia y sus frutos expertos del diario quehacer investigativo, deseaban poder plasmar sus hallazgos, sus pruebas, sus logros científicos, su producción intelectual, en un espacio propio, libre, amplio y vital. Surge entonces la idea de construir, mantener y fortalecer su propio medio de expresión escrita, nace la Revista Colombiana de Ciencia Animal, llamada por su valor RECIA, así sería ella, así debería ser… fuerte y batallante para no desaparecer.