bluuebunny/crossref_metadata_2025 huggingface dataset:
Quality evaluation of the emergency program of three contemporary cell-washing machines
Authors: De Somer Filip , Bernolet Hendrik , Bouchez Stefaan , Bové Thierry
Published: January 2019

This study evaluates the efficiency of emergency programs used by three contemporary cell washers. Both time necessary to process a given amount of blood and quality of the processed blood are investigated. The Fresenius Kabi Smart, Haemonetics Elite and LivaNova Xtra were validated using bovine blood, with a starting hematocrit of 13% or 21%. For all devices, the pre-programmed emergency program was used. The total volume processed in the 13% hematocrit group was 358 ± 68 mL for Fresenius, 375 ± 308 mL for Haemonetics and 497 ± 87 mL for LivaNova. In the 21% hematocrit group, the volumes were 533 ± 60 mL, 713 ± 142 mL and 798 ± 96 mL, respectively, showing a statistical difference between the Fresenius and LivaNova (p = 0.02). In the 13% hematocrit group, the Fresenius processed 45 ± 15 mL blood/min, the Haemonetics 62 ± 8 mL blood/min and the LivaNova 66 ± 1.5 mL blood/min. The difference between the Fresenius and LivaNova was statistically significant (p = 0.04). In the 21% hematocrit group, the processing speed was 69 ± 4 mL blood/min, 62 ± 8 mL blood/min and 77 ± 5 mL blood/min for the Fresenius, LivaNova and Haemonetics, respectively (p = 0.25). No major differences in the elimination of potassium, albumin and total protein or in hemolytic index were observed. No major differences were observed between discontinuous and continuous systems with respect to processing speed and wash quality with a starting hematocrit of 21%. Minor differences in processing speed were observed with a starting hematocrit of 13%.
Assessing quality of care for the dying from the bereaved relatives’ perspective: Using pre-testing survey methods across seven countries to develop an international outcome measure
Authors: Mayland Catriona Rachel , Gerlach Christina , Sigurdardottir Katrin , Hansen Marit Irene Tuen , Leppert Wojciech , Stachowiak Andrzej , Krajewska Maria , Garcia-Yanneo Eduardo , Tripodoro Vilma Adriana , Goldraij Gabriel , Weber Martin , Zambon Lair , Passarini Juliana Nalin , Saad Ivete Bredda , Ellershaw John , Haugen Dagny Faksvåg
Published: January 2019

Background:

The provision of care for dying cancer patients varies on a global basis. In order to improve care, we need to be able to evaluate the current level of care. One method of assessment is to use the views from the bereaved relatives.

Aim:

The aim of this study is to translate and pre-test the ‘Care Of the Dying Evaluation’ (CODETM) questionnaire across seven participating countries prior to conducting an evaluation of current quality of care.

Design:

The three stages were as follows: (1) translation of CODE in keeping with standardised international principles; (2) pre-testing using patient and public involvement and cognitive interviews with bereaved relatives; and (3) utilising a modified nominal group technique to establish a common, core international version of CODE.

Setting/participants:

Hospital settings: for each country, at least five patient and public involvement representatives, selected by purposive sampling, fed back on CODETM questionnaire; and at least five bereaved relatives to cancer patients undertook cognitive interviews. Feedback was collated and categorised into themes relating to clarity, recall, sensitivity and response options. Structured consensus meeting held to determine content of international CODE (i-CODE) questionnaire.

Results:

In total, 48 patient and public involvement representatives and 35 bereaved relatives contributed to the pre-testing stages. No specific question item was recommended for exclusion from CODETM. Revisions to the demographic section were needed to be culturally appropriate.

Conclusion:

Patient and public involvement and bereaved relatives’ perceptions helped enhance the face and content validity of i-CODE. A common, core international questionnaire is now developed with key questions relating to quality of care for the dying.
Improved characterization of cerebral infarction using combined tissue T2 and high b-value diffusion MRI in post-thrombectomy patients: a feasibility study
Authors: Karunamuni Roshan A , White Nathan S , Fromm Annette , Moen Gunnar , Renate Grüner Eli , Dale Anders M , Oltedal Leif
Published: January 2019

Background

The utility of incorporating both diffusion information and T2 relaxation times in the imaging work-up of stroke patients is being investigated in a number of clinical trials and scientific studies. However, these tissue characteristics are often determined both qualitatively and independent of each other.

Purpose

To investigate the feasibility of varying T2- (multi echo time [TE]) and diffusion- (multi b-value) weighting within a single series to detect differences in infarcted tissue in post-thrombectomy patients.

Material and Methods

An experimental magnetic resonance imaging (MRI) diffusion series consisting of multiple b-values (0, 500, 1000, and 4000 s/mm2) and multiple TEs (85, 103, and 120 ms) was implemented. In order to model the signal intensity, an extension of the bi-exponential model to include unique T2 values for each component was formulated. As proof of concept, four stroke patients were imaged the day after thrombectomy. Non-linear optimization tools were used to estimate model parameters in manually drawn regions of interest.

Results

Simulations of signal intensity demonstrated that clinically standard ADC maps acquired solely using b = 1000 s/mm2 data may ignore changes in underlying tissue compartment properties. Analysis of normal-appearing and infarcted tissue in stroke patients demonstrated shifts in T2 relaxation times in both the slow (158 ms [95% confidence interval = 79–236 ms] to 214 ms [86–342 ms]) and fast (82 ms [71–92 ms] to 171 ms [40–303 ms]) diffusion components.

Conclusions

Although results are shown in only a few patients, multi-b-value, multi-echo parameters could provide clinicians and researchers with a more complete understanding of the effective T2 properties of infarcted tissue.
Basic and Advanced Echocardiographic Evaluation of Myocardial Dysfunction in Sepsis and Septic Shock
Authors: Vallabhajosyula S. , Pruthi S. , Shah S. , Wiley B. M. , Mankad S. V. , Jentzer J. C.
Published: January 2019

Sepsis continues to be a leading cause of mortality and morbidity in the intensive care unit. Cardiovascular dysfunction in sepsis is associated with worse short- and long-term outcomes. Sepsis-related myocardial dysfunction is noted in 20%–65% of these patients and manifests as isolated or combined left or right ventricular systolic or diastolic dysfunction Echocardiography is the most commonly used modality for the diagnosis of sepsis-related myocardial dysfunction. With the increasing use of ultrasonography in the intensive care unit, there is a renewed interest in sepsis-related myocardial dysfunction. This review summarises the current scope of literature focused on sepsis-related myocardial dysfunction and highlights the use of basic and advanced echocardiographic techniques for the diagnosis of sepsis-related myocardial dysfunction and the management of sepsis and septic shock.
The Use of a Simple Three-Level Bronchoscopic Assessment of Inhalation Injury to Predict in-Hospital Mortality and Duration of Mechanical Ventilation in Patients with Burns
Authors: Aung M. T. , Garner D. , Pacquola M. , Rosenblum S. , McClure J. , Cleland H. , Pilcher D. V.
Published: January 2019

Major burn centres in Australia use bronchoscopy to assess severity of inhalation injuries despite limited evidence as to how best to classify severity of inhalational injury or its relationship to patient outcomes. All patients with burns who were admitted to the intensive care unit (ICU) at The Alfred Hospital between February 2010 and July 2014 and underwent bronchoscopy to assess inhalational injury, were reviewed. Age, total body surface area burnt, severity of illness indices and mechanisms of injury were extracted from medical histories and local ICU and burns registries. Inhalational injury was classified based on the Abbreviated Injury Score and then grouped into three categories (none/mild, moderate, or severe injury). Univariable and multivariable analyses were undertaken to examine the relationship between inhalational injury and outcomes (in-hospital mortality and duration of mechanical ventilation). One hundred and twenty-eight patients were classified as having none/mild inhalational injury, 81 moderate, and 13 severe inhalation injury. Mortality in each group was 2.3% (3/128), 7.4% (6/81) and 30.7% (4/13) respectively. Median (interquartile range) duration of mechanical ventilation in each group was 26 (11–82) hours, 84 (32–232) hours and 94 (21–146) hours respectively. After adjusting for age, total body surface area burnt and severity of illness, only the severe inhalation injury group was independently associated with increased mortality (odds ratio 20.4 [95% confidence intervals {CI} 1.74 to 239.4], P=0.016). Moderate inhalation injury was independently associated with increased duration of ventilation (odds ratio 2.25 [95% CI 1.53 to 3.31], P <0.001), but not increased mortality. This study suggests that stratification of bronchoscopically-assessed inhalational injury into three categories can provide useful prognostic information about duration of ventilation and mortality. Larger multicentre prospective studies are required to validate these findings.
Morbid Obesity Impairs Adequacy of Thoracic Compressions in a Simulation-Based Model
Authors: Secombe P. J. , Sutherland R. , Johnson R.
Published: January 2019

Adequate cardiopulmonary resuscitation is an important predictor of survival, however, obesity provides a significant physical barrier to thoracic compressions. This study explores the effect of morbid obesity on compression adequacy. We performed a prospective randomised controlled crossover study, assessing the adequacy of thoracic compressions on a manikin modified to emulate a morbidly obese patient. Participants recruited from critical care departments were randomised to perform continuous compressions for two minutes on each manikin. Accelerometers were used to measure thoracic wall movement. The primary endpoint was a composite measure of compression adequacy (rate, depth and recoil). Secondary endpoints were the individual components of the composite outcome and measures of perceived effectiveness, fatigue, and pain. One hundred and one participants were recruited. There was a significant difference between the obese and control groups in the composite endpoint (4% versus 30%, P <0.001), as well as the individual components of adequacy (P <0.01 for all). Quartile data showed significant deterioration in adequacy of depth and recoil in both groups, and this occurred significantly earlier in the obese group (P ≤0.001). Participants’ perception of effectiveness was significantly lower (P ≤0.001) in the obese group, and levels of fatigue (P ≤0.001) and pain (P ≤0.001) significantly higher. Morbid obesity impairs the adequacy of thoracic compressions for trained rescuers in a simulation-based model. Participants were not fully aware of how ineffective compressions were. There is evidence of earlier fatigue further reducing effectiveness. These findings have significant implications for the training of rescuers in a clinically relevant population and the planning of future research.
Morbidity of Cardiac Arrest in the Very Elderly
Authors: Paterson T. L. , Bruins S. D.
Published: January 2019

The objective of this retrospective cohort study was to assess mortality and morbidity after cardiac arrest in hospital inpatients aged 80 years or older, in an Australian tertiary hospital. We studied patients aged 80 years or older who suffered an in-hospital cardiac arrest from 1 January 2000 to 31 December 2016. The main outcome measures were one-year survival and narrative morbidity. Two hundred and eighty-five patients were identified. Absolute one-year survival after cardiac arrest was, at best, 12.6%. Narrative descriptions of morbidity demonstrate high healthcare utilisation, dependency or residential care, and significant impairments of physical and social function. In conclusion, one-year survival after cardiac arrest in the very elderly is poor. In those who survive, significant morbidity is present.
An International Survey Evaluating Factors Influencing the Use of Total Intravenous Anaesthesia
Authors: Wong G. T. C. , Choi S. W. , Tran D. H. , Kulkarni H. , Irwin M.
Published: January 2019

The purpose of this study was to evaluate factors influencing the use of propofol-based total intravenous anaesthesia (TIVA) since despite TIVA being a well-established technique, it is used far less frequently than volatile anaesthesia. Questions were formulated after reviewing the literature for perceived disadvantages of TIVA and meeting with a focus group consisting of both senior and junior anaesthestists from our department. Once the survey had been formulated, specialist anaesthetists from professional colleges and societies from several countries were invited to complete the survey on an electronic web-based platform to allow evaluation of the respondent's rating of the importance of a range of factors in their decision not to use TIVA for a particular case. Basic descriptive statistics were determined using SPSS statistical software, while graphical depictions of data were handled using R for statistical analysis. A total of 763 survey responses were included in the final analysis and stratified according to the frequency of TIVA use. Among the infrequent users, issues such as additional effort, institutional preference, lack of real-time monitoring of propofol concentration, risk of missing drug delivery failure and increased turnaround time were among the top reasons mentioned. Interestingly, these issues were considered far less important among the frequent users when not choosing TIVA. We concluded that frequent and infrequent users respond quite differently to similar technical TIVA-related factors. Non-technical factors may play an important role in the infrequent user's decision not to use TIVA for a particular case.
Introduction of a Mandatory Pre-Block Safety Checklist into a Regional Anaesthesia Block Room Service: A Quality Improvement Project
Authors: McLellan E. J. , Hade A. D. , Pelecanos A. , Okano S.
Published: January 2019

Wrong-side block is an uncommon yet potentially preventable complication of regional anaesthesia. One strategy for reducing the incidence of wrong-side block is to introduce an additional check into the pre-block workflow in the form of a block ‘time out’ or ‘stop before you block’. In the aftermath of a wrong-side block incident at our institution, the mandatory use of a pre-block safety checklist was successfully introduced into the workflow of the block room. Compliance with the checklist rose from 31% in the six-month pre-intervention phase to over 90% in the six-month post-intervention phase. This was achieved without any negative effect on block efficacy, theatre efficiency, complication rates or patient satisfaction. The high rate of checklist utilisation was associated with an increased rate of ultrasound video documentation. This suggests that there may be collateral benefit to using a pre-block safety checklist in addition to merely reducing the risk of wrong-side block.
Retrieval of Critically Ill Adults Using Extracorporeal Membrane Oxygenation: The Nine-Year Experience in New South Wales
Authors: Austin D. E. , Burns B. , Lowe D. , Cartwright B. , Clarke A. , Dennis M. , D'Souza M. , Nathan R. , Bannon P. G. , Gattas D. , Connellan M. , Forrest P.
Published: January 2019

In New South Wales, a coordinated extracorporeal membrane oxygenation (ECMO) retrieval program has been in operation since 2007. This study describes the characteristics and outcomes of patients transported by this service. We performed a retrospective observational study and included patients who were transported on ECMO to either of two adult tertiary referral hospitals in Sydney, New South Wales, between February 28, 2007 and February 29, 2016. One hundred and sixty-four ECMO-facilitated transports occurred, involving 160 patients. Of these, 118 patients (74%) were treated with veno-venous (VV) ECMO and 42 patients (26%) were treated with veno-arterial ECMO. The mean (standard deviation, SD) age was 40.4 (15.0) years. Seventy-seven transports (47%) occurred within metropolitan Sydney, 52 (32%) were from rural or regional areas within NSW, 17 (10%) were interstate transfers and 18 (11%) were international transfers. Transfers were by road (58%), fixed wing aircraft (27%) or helicopter (15%). No deaths occurred during transport. The median (interquartile range) duration of ECMO treatment was 8.9 (5.2–15.3) days. One hundred and nineteen patients (74%) were successfully weaned from ECMO and 109 (68%) survived to hospital discharge or transfer. In patients treated with VV ECMO, age, sequential organ failure assessment score, pre-existing immunosuppressive disease, pre-existing diabetes, renal failure requiring dialysis and failed prone positioning prior to ECMO were independently associated with increased mortality. ECMO-facilitated patient transport is feasible, safe, and results in acceptable short-term outcomes. The NSW ECMO Retrieval Service provides specialised support to patients with severe respiratory and cardiovascular illness, who may otherwise be too unstable to undergo inter-hospital transfer to access advanced cardiovascular and critical care services.
Peripheral Tissue Oxygenation and the Number of Organs Transplanted per Donor
Authors: Perez-Protto S. E. , Reynolds J. D. , Nazemian R. , You J. , Hata J. S. , Latifi S. Q. , Lebovitz D. J.
Published: January 2019

Current donor management practices target macrohaemodynamic parameters, but it is unclear if this leads to improvements in microvascular perfusion and tissue oxygenation; the latter may have more impact on organ status. In a recent preclinical study we determined that brain death impaired tissue perfusion and oxygen utilisation in swine while pharmacologic correction of these deficits improved organ function and reduced markers of tissue injury. As a first step in translating the preclinical findings, we conducted a prospective observational study to determine if there was an association between peripheral tissue oxygenation (measured by near-infrared spectroscopy) in deceased by neurological criteria human donors and the number of organs transplanted. In 60 donors, the mean time-weighted average of tissue oxygenation was 87.5% (standard deviation, SD, 5.2%) and the average number of organs transplanted was 3.5 (SD 2); there was a positive linear relationship between these two parameters. A 5% rise in tissue oxygenation was associated with an increase of 0.47 organs transplanted (95% confidence intervals 0.16 to 0.78) after adjusting for age (P=0.004). No such correlations were observed for the macrohaemodynamic or macro-oxygenation parameters (including arterial blood oxygenation). The results of this clinical trial are consistent with our preclinical work and support the postulate that targeting the microvasculature to improve tissue perfusion and tissue oxygen delivery in human donors has the potential to increase the quantity of organs suitable for transplant.
An Audit of the Diagnostic Accuracy of Rotational Thromboelastometry for the Identification of Hypofibrinogenaemia and Thrombocytopenia during Cardiopulmonary Bypass
Authors: Matzelle S. A. , Weightman W. M. , Gibbs N. M.
Published: January 2019

We audited the diagnostic accuracy of ROTEM® (TEM Innovations, GmbH, Munich, Germany) measurements of hypofibrinogenaemia (fibrinogen <1.5 g/l) and thrombocytopenia (platelet count <100 × 109/l) in 200 adult non-transplant patients during cardiopulmonary bypass (CPB). Blood samples were obtained for FIBTEM (assay for the fibrin part of the clot), PLTEM (calculated platelet-specific component), and laboratory measurements simultaneously. Our thresholds for FIBTEM and PLTEM were A10 (clot firmness 10 minutes after clotting time) ≤8 mm, and <35 mm respectively. We also calculated the accuracy of smaller thresholds and earlier indices. We found that FIBTEM A10 ≤8 mm had low sensitivity (0.62) for hypofibrinogenaemia. With the 13% hypofibrinogenaemia prevalence in our sample, the positive predictive value (PPV) was 0.47. In contrast, FIBTEM A10 ≤8 mm had higher specificity (0.90) (negative predictive value [NPV] 0.94). Of the other FIBTEM values analysed, only A5 ≤6 mm had similar or superior accuracy. The PLTEM results were less encouraging (sensitivity 0.81, specificity 0.62). With our prevalence of thrombocytopenia (also 13%), the PPV was only 0.24. However, the NPV was high (0.96). Of the other PLTEM values analysed, only A5 <25 mm had similar or superior accuracy. These findings indicate that during CPB FIBTEM A10 ≤8 mm and PLTEM A10 <35 mm have greater accuracy in identifying the absence of hypofibrinogenaemia and thrombocytopenia respectively than their presence. On the basis of these results we would be reassured by FIBTEM A10 values >8 mm and PLTEM A10 values ≥35 mm, but would continue to use laboratory measurements for confirmation. We would not use FIBTEM A10 ≤8 mm or PLTEM A10 <35 mm values alone to guide replacement therapy unless clinical conditions warranted an immediate decision before laboratory measurements were available.
Maintenance Facility Location Optimization Review
Authors: Holik William
Published: January 2019

State departments of transportation (DOTs) are responsible for operating and maintaining the highway system in a safe and efficient manner to facilitate the movement of people and goods. Maintenance facilities play a critical role in the operations of DOTs by storing equipment and materials, providing a base of operation for department of transportation personnel, and serving as the beginning and ending location for maintenance activities. Maintenance activities occur year-round, but winter maintenance activities are typically the most time and resource intensive for northern state DOTs. Maintenance operations generally consist of facilities, routes, and equipment. The life spans of maintenance facilities are typically measured in decades, which compounds any inefficiencies in their locations over a long time horizon. Less research has been conducted to optimize facility locations than routes and fleets. This paper reviews the available literature related to facility optimization, including maintenance facilities and non-maintenance facilities. Several specific takeaways were documented from the research reviewed. DOTs have conducted research to optimize the locations of their facilities. These works have typically examined a small area and included only a few facilities. The larger-scale optimizations only located facilities at the town level. A second level of facilities may be necessary to improve the cost effectiveness of the optimization. Such facilities could include material storage depots strategically placed between maintenance sections to reduce the amount of deadheading. At a certain point, further consolidation of maintenance facilities will increase the overall costs because more vehicles and staff are required to reach the further extents of maintenance areas.
Delamination Does Not Affect Outcomes After Arthroscopic Rotator Cuff Repair as Compared With Nondelaminated Rotator Cuff Tears: A Study of 1043 Consecutive Cases
Authors: Kwon Jieun , Lee Ye Hyun , Kim Sae Hoon , Ko Jung Hoon , Park Byung Kyu , Oh Joo Han
Published: January 2019

Background:

Limited information is available regarding the characteristics of delaminated rotator cuff tears as compared with nondelaminated tears. Furthermore, there is conflicting information regarding the effects of delamination on the anatomic healing of repaired cuffs.

Purpose:

To evaluate the characteristics and anatomic outcomes of delaminated rotator cuff tears in comparison with nondelaminated tears to determine whether delamination is a negative prognostic factor affecting rotator cuff repair outcomes.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Between 2010 and 2014, 1043 patients were enrolled in the study to assess the prevalence of delamination. Among them, the findings from 531 patients who underwent magnetic resonance imaging or computed tomographic arthrography at least 1 year after surgery were included to determine whether delamination was a negative prognostic factor affecting the anatomic outcomes of arthroscopic rotator cuff repair. Delamination was assessed intraoperatively and defined by distinguishable edge cleavage tearing or interstitial horizontal gap between the articular and bursal surfaces of the torn tendon. One of 3 repair techniques (modified Mason Allen, single row, or double row) was used according to tear configuration and tendon mobilization. The authors evaluated visual analog scale scores for pain and satisfaction and American Shoulder and Elbow Surgeons scores to quantify clinical outcomes.

Results:

The incidence of delamination was 42.9% (447 of 1043). As compared with those with nondelaminated tears, patients with delaminated tears were older ( P < .001) and had longer symptom duration ( P = .019), larger tear sizes and retractions ( P < .001 for both), higher grades of fatty infiltration of the rotator cuff muscles (all P < .001), and poorer tendon quality ( P < .001). The overall healing failure rate was 19.0% (101 of 531). In univariate analysis, the rate of healing failure for the repaired cuffs was significantly higher in the delaminated group (delaminated tears, 60 of 238, 25.2%; nondelaminated tears, 41 of 293, 14.0%; P = .001). However, results of subgroup and multivariate analyses showed that the presence of delamination was ultimately not an independent risk factor for the failure of cuff healing. Between the delaminated and nondelaminated groups, there was no significant difference in postoperative functional outcomes.

Conclusion:

The results suggest that delaminated rotator cuff tears might represent chronic degenerative tears of longer symptom duration, with larger tear sizes and higher grades of fatty infiltration in older patients. It appears that delamination could be a confounding factor, not an independent prognostic factor, affecting rotator cuff healing.
Challenges Assessing the Conceptual Understanding of Students With Disabilities in Statistics
Authors: Dahlstrom-Hakki Ibrahim H. , Alstad Zachary G.
Published: January 2019

Standardized assessment of content knowledge for STEM (Science, Technology, Engineering, Mathematics) topics is pervasive in both K-12 and postsecondary institutions. Yet, most instruments are developed with little to no validation for students with learning disability (LD), attention deficit hyperactivity disorder (ADHD), and autism spectrum disorder (ASD). In this study, we evaluate the effectiveness of new test instruments designed to assess conceptual understanding of statistics content and the extent to which construct-irrelevant factors, such as language processing, influence the performance of students with disabilities. Generalized linear mixed-effects modeling was used to identify the factors that were predictive of student performance. Results indicate that the average sentence length in word problems was uniquely predictive of student performance on emerging assessments of conceptual understanding. The results provide new evidence of the barriers facing students with disabilities on emerging tests of conceptual knowledge. A general framework for measuring the impact of these barriers and the effectiveness of accommodations is discussed.
Environmental and economic advantages of adopting reverse logistics for recycling construction and demolition waste: A case study of Brazilian construction and recycling companies
Authors: Oliveira Neto Geraldo C , Correia José MF
Published: January 2019

The aim of this study was to assess the economic and environmental advantages of implementing reverse logistics to recycle solid waste from construction companies. The adopted research method was based on a systematic literature review and two case studies. For the economic assessment, the return on investment, the internal rate of return, and the discounted payback factors were considered, while the material intensity factor was used for the environmental impact assessment. This study shows that there are economic and environmental advantages associated with the use of reverse logistics for solid waste treatment and recycling. In 2016, the purchase of recycled blocks resulted in a profit of over US$45,000 for one company, and another company earned almost US$250,000 in the same year by recycling solid waste from manufacturing blocks and selling iron, wood, paper, and plastics. Furthermore, the environmental impact was reduced. This paper contributes to the dissemination of knowledge regarding the advantages of adopting reverse logistics for recycling construction and demolition waste, and creates new opportunities for companies.
Super-hydrophobic and super-oleophilic surface based on high-density polyethylene/waste ground rubber tire powder thermoplastic elastomer
Authors: Shi Yujiao , Sun Yingtao , Wang Zhaobo
Published: January 2019

Super-hydrophobic and super-oleophilic surface based on high-density polyethylene/styrene–butadiene–styrene block copolymer/waste ground rubber tire powder thermoplastic elastomer (TPE) was successfully prepared while metallographic sandpaper was used as a template. Field emission scanning electron microscope study showed that the molded TPE surface with W7 grade sandpaper possessed the rough microstructure; moreover, the micrometer scale strips resulting from the plastic deformation of TPE matrix could be observed obviously, leading to the increasing surface roughness. Wettability tests showed that the molded TPE surfaces with series sandpapers exhibited the hydrophobic and super-oleophilic properties; moreover, the surface molded with W7 grade sandpaper showed the remarkable super-hydrophobic and super-oleophilic properties.
Effect of cellulose nanofibers from cassava pulp on physical properties of poly(lactic acid) biocomposites
Authors: Nguyen Thanh Chi , Ruksakulpiwat Chaiwat , Ruksakulpiwat Yupaporn
Published: January 2019

Biocomposites of poly(lactic acid) (PLA) and cellulose nanofibers (CNFs) extracted from cassava pulp were successfully prepared by melt mixing in an internal mixer. CNFs were prepared from cassava pulp by submitting to alkali hydrolysis, bleaching treatment, and acid hydrolysis. The compatibility between CNFs and PLA matrix was improved using glycidyl methacrylate (GMA) grafted PLA (PLA-g-GMA) as an effective compatibilizer. Higher elongation at break and impact strength of PLA/PLA-g-GMA/CNFs biocomposites was achieved compared to that of neat PLA. PLA-g-GMA shows a strong effect on the crystallization behavior of the biocomposites. The PLA/PLA-g-GMA/CNFs biocomposites induce cold crystallization to take place at lower temperature. Higher degree of crystallinity of PLA/PLA-g-GMA/CNFs biocomposites was obtained compared to PLA/CNFs biocomposites. The mechanical and thermal properties of PLA/CNFs biocomposites at various ratios were investigated. With increasing CNFs contents, the modulus of the biocomposites increases. Thermal stability of PLA/CNFs and PLA/PLA-g-GMA/CNFs biocomposites did not change significantly compared to that of neat PLA.
Evaluating the Use of Phenobarbital for the Management of Alcohol Withdrawal Syndrome in Psychiatric Inpatients
Authors: Waldee Erin , Phan Stephanie V.
Published: January 2019

Objectives

To describe the potential role of phenobarbital as appropriate therapy in the treatment and prevention of alcohol withdrawal syndrome (AWS) among medically cleared psychiatric inpatients.

Methods

This was a single-center, retrospective, observational study of adult patients admitted to the psychiatric unit and administered phenobarbital for the treatment or prevention of AWS. Changes in vital signs and signs and symptoms of AWS were observed to assess the safety and efficacy of phenobarbital. The primary outcome was safety of phenobarbital for AWS as measured by change in the respiratory rate (RR).

Results

A total of 122 patients were included in the study. There were no significant changes in RR among patients who received phenobarbital for AWS. Significant reductions in blood pressure and heart rate were observed. Of patients with documented signs and symptoms of AWS upon admission, 94% had improvement in the signs and symptoms during phenobarbital therapy. Approximately 12% of patients had documented sedation or altered mental status during phenobarbital therapy. No patients required transfer to a medical or critical care unit.

Conclusions

Phenobarbital was safe, not leading to severe adverse effects or requiring a higher level of care, and efficacious for the prevention and treatment of AWS in this cohort of psychiatric inpatients.
Generalization of the tetraparametric assembly method for the optimization of bolt tightening sequences in ring-type joints
Authors: Coria Ibai , Abasolo Mikel , Aguirrebeitia Josu , Fernández de Bustos Igor
Published: January 2019

Uniform bolt load is critical to achieve leak-free service in pressure vessel gasketed joints. In a previous work, the authors presented the tetraparametric assembly method, which enabled to obtain a uniform final load distribution in a one-pass tightening sequence. The accuracy of the method was proved by finite element analysis and experimental tests. However, the tetraparametric assembly method was only developed for one-pass tightening sequences, and in some cases more than one pass can be necessary. Furthermore, the method was only validated for a particular joint geometry. In this sense, the present work generalizes the method for two-pass tightening sequences and studies the range of application.
Point-of-care diagnostics: needs of African health care workers and their role combating global antimicrobial resistance
Authors: Parkes-Ratanshi Rosalind , Kikonyogo Ruth , Hsieh Yu-Hsiang , Nakku-Joloba Edith , Manabe Yukari C , Gaydos Charlotte A , Rompalo Anne
Published: January 2019

Point-of-care tests (POCTs) offer the opportunity for increased diagnostic capacity in resource-limited settings, where there is lack of electricity, technical capacity, reagents, and infrastructure. Understanding how POCTs are currently used and determining what health care workers (HCWs) need is key to development of appropriate tests. In 2016, we undertook an email survey of 7584 HCWs who had received training at the Infectious Diseases Institute, Uganda, in a wide variety of courses. HCWs were contacted up to three times and asked to complete the survey using Qualtrics software. Of 555 participants answering the survey (7.3% response rate), 62% completed. Ninety-one percent were from Uganda and 50.3% were male. The most commonly-used POCTs were pregnancy tests (74%), urine dipstick (71%), syphilis rapid test (66%), and Gram stain (41%). The majority (74%) practiced syndromic diagnosis for sexually transmitted infections/HIV. Lack of availability of POCTs, increased patient wait time, and lack of training were the leading barriers for POCT use. Increasing POCT availability and training could improve uptake of POCTs for sexually transmitted infections in Africa and decrease syndromic management. This could reduce overtreatment and slow the emergence of antibiotic resistance. This is the first published email survey of HCWs in Uganda; mechanisms to increase the response rate should be evaluated.
Investigation of the premixed methane–air combustion through the combined porous-free flame burner by numerical simulation
Authors: Hashemi Seyed Mohammad , Hashemi Seyed Abdolmehdi
Published: January 2019

Combustion process of the premixed methane–air in a novel combined porous-free flame burner was investigated numerically. Two-dimensional model considering nonequilibrium thermal condition between the gas and solid phases was used and the combustion was simulated using reduced GRI 3.0 multistep chemical kinetics mechanism. To examine the validity of the implemented numerical model, the burner was manufactured and tested. Good agreement between the numerical results and experimental data were observed. Thermal flame thickness, flame stability limit, and thermal efficiency were discussed. Multimode heat transfer in the porous medium including convection, radiation, and conduction were quantified and perused. Results showed that the thermal thickness of laminar free flame established in the perforated portion of the burner was considerably less than thickness of submerged flame stabilized in the porous medium. Predicted results suggested that the flame stability limit was augmented in the combined burner compared to the burner with full porous foam. Analyses of the heat balance showed that the thermal efficiency of the combined porous-free flame burner was less than thermal efficiency of the full porous burner. Comparison of the full porous burner with the novel combined porous-free flame burner demonstrated that the combined burner caused higher stability limits and lower thermal efficiencies.
Simulation model of an off-road four-wheel-driven electric vehicle
Authors: Miroslaw Tomasz , Szlagowski Jan , Zawadzki Adam , Zebrowski Zbigniew
Published: January 2019

Electric vehicle gives much more advantages than only less air polluting or less noisy mobility. The current technology enables engineers to better control the electric motor than internal combustion engine. Electronic components like transistors, which can be switched on and off almost anytime, help to control the motor current and indirectly the torque and the speed. The progress in power electronics and motor construction opens new possibilities in vehicle construction and control. The process of wheel rolling can be better controlled which is very important especially on deformed surface of a road. The movement resistance can be reduced by smart power distribution between front and rear wheels in 4 × 4 drive vehicles, where front wheels can compact the ground and rear wheels can move on the rigid road. To reach all the advantages, we need a better understanding of a processes occurring in electric vehicles’ systems, which consist of motors, gears, and wheels reacting with ground. Authors present the model of 4 × 4 drive vehicle focused on this last, but not least, problem—part of an electric vehicle model which is the wheel–ground cooperation. This subsystem decides about power flow from the motor to the wheel and about traction and movement efficiency. This problem is not new, but flexible driving manner going with electric drive makes these analyses more practical and can be used in off-road electric vehicles. The analyses were supported by model and simulation prepared with MATLAB/Simulink software. In conclusion, the comparison of various drive properties and possibilities is presented and recommendations for further development are suggested.
On the strength of Toray 1000/Der332 Composites
Authors: Feng William W , Groves Scott E
Published: January 2019

The finite-strain-invariant criterion is applied to Toray 1000 / DER332 symmetrically balanced angle-ply laminates subjected to a uniaxial loading state. The results indicate that the initial failures are all in the matrix failure mode.
Production of Metal Fiber by Coiled Sheet Slicing Method and Its Composite Materials
Authors: Yanagisawa A , Kaneko M , Nakagawa T
Published: January 2019

A new manufacturing process of long-length metal fiber which can be applied to the composite materials has been developed. In this new process, the metal fiber is produced out of coiled thin metallic sheet by a new slicing method. In the manufacturing trial, each specific cutting conditions for fiber production from brass and either copper or stainless steel has been confirmed. This method has high productivity and applicability for many kind of materials. Then, the metal fiber obtained this method can be used for various fields of composite materials1).

As one of the important characteristics of this method, it is capable that a uniformly mixed different material fibers can be easily produced with different material sheets such as metal, plastics and paper and so on, which are wound layer by layer. Using a uniformly mixed fiber of plastics and metals, the plastic pellet and sheet including metal fiber has been produced. Further, the electric conductive composite materials has been developed utilizing the plastic pellets and sheets.
Preparation of High Char-Yield Phenolic Resins
Authors: Jwo S L , Chen J C , Chen W Y , Hsu S E
Published: January 2019

Phenolic resin synthesized by a formaldehyde/phenol(F/P) molar ratio of 1.3: 1 with different catalysts has been studied. High char yield can be obtained for the synthesized resin with NaOH or Na2CO3 catalyst at lover heating rate during carbonization the highest char yield about 71.0% was found.
Local Stress Fields in A Unidirectional Fiber-Reinforced Composite with A Non-Homogeneous Interphase Region: Solution
Authors: Jayaraman K , Reifsnider K L
Published: January 2019

Attention has been focused recently on the interphase in continuous, unidirectional fiber-reinforced composites. In this study, the interphase region is modeled as a non-homogeneous, orthotropic material with continuously varying properties. A previously proposed solution method is used to determine the local stress fields in the constituents - the fiber, interphase and matrix - and the results are presented.
Surface Induced Crystallization in Fibre Reinforced Nylon 6,6 Composites
Authors: Klein N , Marom G
Published: January 2019

The present study deals with the growth of transcrystalline layer in Nylon 6,6 reinforced with HM pitch based carbon or aramid fibres. The kinetics of transcrystalline growth is investigated quantitatively. The surface energy parameters that are derived here, can be used to define a better criterion for the nucleation of transcrystallinity from the fibre surface. The free energy difference function, Δσ, as it appears in the classical theory of heterogeneous nucleation is calculated for both aramid and HM carbon fibres.
A New Mode Iii Delamination Test for Composites
Authors: Robinson P , Song D Q
Published: January 2019

This letter reports a concept for a Mode III test method which eliminates the Mode II component experienced with the split cantilever beam test method. The success of the design is demonstrated by finite element analyses and by SEM fracture surface photographs. Initial test results are reported for a carbon fibre epoxy composite.
Effects of Bundle geometry of Fit® Material Pre-Forms on Consolidation process of Thermoplastic Composites
Authors: Ye L , Friedrich K , Cutolo D
Published: January 2019

Effects of variations in bundle geometry on consolidation behavior of FIT® material pre-forms are discussed. The results for CF/PEEK composites indicate that increasing in the shape-ratio of the FIT® material is one way to improve the impregnation process and consolidation quality in manufacturing thermoplastic composite parts.
Application of Electrical Resistance Method in study of Sic/Al Composite
Authors: Liu X C
Published: January 2019

In SiC/Al composite there are obvious correspondent relations between electrical resistivity and F/M interfaces change as well as Vf. Both the F/M reaction reaction and Vf can be determined by means of the composite electrical resistivity, if the resistivity is revised by a factor small than 1.
Fabrication of Knitted Glass Fibre Fabric Reinforced Thermoplastic Composite Laminates
Authors: Ramakrishna S. , Hamada H. , Cuong N.K.
Published: January 2019

It has been shown that knitted fabric reinforced thermoplastic composites can be fabricated by compression moulding in two ways namely, film stacking method and co-knitted fabric method. The processability of co-knitted fabric method was better than the film stacking method. Tensile properties in the wale direction of the knitted fabric were higher than those of the course direction.
Skin Thickness Variation during Resin Transfer moulding of Sandwich Structures
Authors: Al-Hamdan A. , Tufail M. , Rudd C.D. , Long A.C.
Published: January 2019

Resin transfer moulding (RTM) and structural reaction injection moulding (SRIM), are liquid composite moulding processes, whereby a resin is transferred into a mould cavity containing a pre-positioned reinforcement preform. The cost and the weight of the product may be reduced by placing a foam inside the preform. During the process, the fluid pressure can result in shifting of the core, which causes manufacturing defects such as skin thickness variation, affecting the mechanical properties of the skin. The factors causing this shifting are identified in this study. The influence of fluid pressure and mould temperature on skin thickness ratio is examined experimentally and compared with the output from a simple model.
The birth of public space privatization: How entrepreneurialism, convivial urbanism and stakeholder interactions made the Martim Moniz square, in Lisbon, ‘privatization-ready’
Authors: Gomes Pedro
Published: January 2019

Despite the vigorous debate on the extent, modalities and impacts of public space privatization, there have been few analyses of the processes of its emergence in specific places. Based on 36 stakeholder interviews and desk research, this paper does so through an analysis of how the Martim Moniz square, in Lisbon, became the city’s first square under private management in 2012. To do so, the paper goes through the local governance context and the importance of convivial public spaces as a political objective, leading to regular partnerships with non-state actors. The square is adjacent to Mouraria, a derelict neighbourhood that was a testing ground for the city’s new urban policies. The square’s private management scheme – branded the Mercado de Fusão – rather than a rupture with existing practices, is the result of a coincidence of interests of both actors. Moreover, it reassembles typical local policy responses and the company’s expertise in a unitary management scheme. The seamless implementation of the Mercado is made possible by the pre-existing relationship between the company and the municipality. The paper thus shows that there is no fundamental shift towards private governance in Lisbon. Rather, it is the generalized commodification of public spaces resulting from the emergence of conviviality as a political objective that opened up the conditions for the square’s privatization. The relationship between conviviality as a political objective and privatization is presented as a promising subject for further research.
What Influences Saturation? Estimating Sample Sizes in Focus Group Research
Authors: Hennink Monique M. , Kaiser Bonnie N. , Weber Mary Beth
Published: January 2019

Saturation is commonly used to determine sample sizes in qualitative research, yet there is little guidance on what influences saturation. We aimed to assess saturation and identify parameters to estimate sample sizes for focus group studies in advance of data collection. We used two approaches to assess saturation in data from 10 focus group discussions. Four focus groups were sufficient to identify a range of new issues (code saturation), but more groups were needed to fully understand these issues (meaning saturation). Group stratification influenced meaning saturation, whereby one focus group per stratum was needed to identify issues; two groups per stratum provided a more comprehensive understanding of issues, but more groups per stratum provided little additional benefit. We identify six parameters influencing saturation in focus group data: study purpose, type of codes, group stratification, number of groups per stratum, and type and degree of saturation.
Medicaid's Role for Children with Special Health Care Needs
Authors: Musumeci MaryBeth
Published: January 2019

This commentary explores Medicaid's role for children with special health care needs today and considers how changes to Medicaid's federal financing structure under a per capita cap or block grant could affect coverage for these children.