Investigation of the Fabrication Suitability,Structural Performance,and Sustainability of Natural Fibers in Coreless Filament Winding

Coreless filament winding is an emerging fabrication technology in the field of building construction with the potential to significantly decrease construction material consumption, while being fully automatable. Therefore, this technology could offer a solution to the increasing worldwide demand for building floor space in the next decades by optimizing and reducing the material usage. Current research focuses mainly on the design and engineering aspects while using carbon and glass fibers with epoxy resin; however, in order to move towards more sustainable structures, other fiber and resin material systems should also be assessed. This study integrates a selection of potential alternative fibers into the coreless filament winding process by adapting the fabrication equipment and process. A bio-based epoxy resin was introduced and compared to a conventional petroleum-based one. Generic coreless wound components were created for evaluating the fabrication suitability of selected alternative fibers. Four-point bending tests were performed for assessing the structural performance in relation to the sustainability of twelve alternative fibers and two resins. In this study, embodied energy and global warming potential from the literature were used as life-cycle assessment indexes to compare the material systems. Among the investigated fibers, flax showed the highest potential while bio-based resins are advisable at low fiber volume ratios.     

Optimization of Optical Machine Structure by Backpropagation Neural Network Based on Particle Swarm Optimization and Bayesian Regularization Algorithms

Fit of the highly nonlinear functional relationship between input variables and output response is important and challenging for the optical machine structure optimization design process. The backpropagation neural network method based on particle swarm optimization and Bayesian regularization algorithms (called BMPB) is proposed to solve this problem. A prediction model of the mass and first-order modal frequency of the supporting structure is developed using the supporting structure as an example. The first-order modal frequency is used as the constraint condition to optimize the lightweight design of the supporting structure’s mass. Results show that the prediction model has more than 99% accuracy in predicting the mass and the first-order modal frequency of the supporting structure, and converges quickly in the supporting structure’s mass-optimization process. The supporting structure results demonstrate the advantages of the method proposed in the article in terms of high accuracy and efficiency. The study in this paper provides an effective method for the optimized design of optical machine structures.     

First clinical experience of a novel penetration catheter for patients with severe coronary artery stenosis.

The study aimed to evaluate the efficacy of a novel penetration catheter for severe coronary artery disease. Severe coronary artery diseases such as chronic total occlusions or severe calcified stenoses sometimes obstruct the subsequent crossing of balloon catheter after successful wire crossing. A novel penetration over-the-wire catheter has been developed for severe coronary artery disease. The main shaft is a coreless stainless coil that consists of eight stranded stainless wires to cross through a severe stenosis by manual rotation. This device was applied during percutaneous coronary intervention for patients with severe coronary artery disease obstructing the subsequent crossing of balloon or microcatheters after successful wire crossing. Initial results were examined. Fourteen eligible patients were enrolled consecutively. Among those, 10 patients had chronic total occlusion and 7 patients showed severe angiographical calcification. The device was successfully crossed through the lesion and enabled subsequent dilatation in all patients without any complication. This new device enables the crossing of severe coronary artery stenoses and therefore favors further dilatation in this lesion subset.     

The application of simple metrics in the assessment of glycaemic variability

The assessment of glycaemic variability (GV) remains a subject of debate with many indices proposed to represent either short- (acute glucose fluctuations) or long-term GV (variations of HbA_1c). For the assessment of short-term within-day GV, the coefficient of variation for glucose (%CV) defined as the standard deviation adjusted on the 24-h mean glucose concentration is easy to perform and with a threshold of 36%, recently adopted by the international consensus on use of continuous glucose monitoring, separating stable from labile glycaemic states. More complex metrics such as the Low Blood Glucose Index (LBGI) or High Blood Glucose Index (HBGI) allow the risk of hypo or hyperglycaemic episodes, respectively to be assessed although in clinical practice its application is limited due to the need for more complex computation. This also applies to other indices of short-term intraday GV including the mean amplitude of glycemic excursions (MAGE), Shlichtkrull's M-value and CONGA. GV is important clinically as exaggerated glucose fluctuations are associated with an enhanced risk of adverse cardiovascular outcomes due primarily to hypoglycaemia. In contrast, there is at present no compelling evidence that elevated short-term GV is an independent risk factor of microvascular complications of diabetes. Concerning long-term GV there are numerous studies supporting its association with an enhanced risk of cardiovascular events. However, this association raises the question as to whether the impact of long-term variability is not simply the consequence of repeated exposure to short-term GV or ambient chronic hyperglycaemia. The renewed emphasis on glucose monitoring with the introduction of continuous glucose monitoring technologies can benefit from the introduction and application of simple metrics for describing GV along with supporting recommendations.     

Low-molecular weight heparins in coronary artery disease

Recently published trials strongly support the use of low-molecular weight heparins in the treatment of unstable coronary syndromes. These agents provide an alternative to heparin that is at least as effective and safe, and does not require intravenous infusions or meticulous monitoring. Although comparative trials are not yet available, the available evidence allows for selection of specific agents in acute management of unstable angina. This review summarizes the current clinical data supporting the use of these agents.     

The pathogenesis of Hemorrhoids

The structure of the anal canal was examined in histology slides. Hemorrhoids are normal features of the human anatomy. They are pads that bulge into the lumen. Hemorrhoids have three parts: 1) the lining, which can be mucosa or anoderm; 2) the stroma with blood vessels, smooth muscle, and supporting connective tissue; and 3) the anchoring connective tissue system, which secures the hemorrhoids to the internal sphincter and the conjoined longitudinal coat. The anchoring and supporting connective tissue system deteriorates with aging. The hemorrhoids not only bulge, but descend into the lumen. This becomes observable in the third decade of life, with individual differences. The veins become distended as they lose their support. The descended loose lining becomes more sensitive to pressure from straining and to trauma from the stool. There can be a stasis in the veins, with clot formations and swelling, or erosions of the lining, with bleeding. The hemorrhoids become symptomatic.     

ECG Patch Monitors for Assessment of Cardiac Rhythm Abnormalities

The primary goal of long-term monitoring is the improvement of diagnostic yield. Despite the clear utility of Holter monitoring in clinical cardiology, issues of relatively low diagnostic yield, cost and inconvenience have motivated the development of ultra-portable devices referred to as ECG patch monitors. Although the “gold standard” for assessing cardiac rhythm abnormalities remains a 12-lead Holter, there is an increasing interest in portable monitoring devices that provide the opportunity for evaluating cardiac rhythm in real-world environments such as the workplace or home. To facilitate patient acceptance these monitors underwent a radical miniaturization and redesign to include wireless communication, water proofing and a patch carrier for attaching devices directly to the skin. We review recent developments in the field of “patch” devices primarily designed for very long-term monitoring of cardiac arrhythmic events. As the body of supporting clinical validation data grows, these devices hold promise for a variety of cardiac monitoring applications. From a clinical and research standpoint, the capacity to obtain longitudinal cardiac activity data by patch devices may have significant implications for device selection, monitoring duration, and care pathways for arrhythmia evaluation and atrial fibrillation surveillance. From a research standpoint, the new devices may allow for the development of novel diagnostic algorithms with the goal of finding patterns and correlations with exercise and drug regimens.     

Activity, damage and outcome in systemic vasculitis

Current therapy has transformed the prognosis of the systemic vasculitides from diseases that had a high acute mortality rate to chronic relapsing diseases with high rates of morbidity. This improved survival has highlighted the need for better methods of monitoring disease activity and recording the accumulation of organ damage that occurs during the course of the disease. Several clinical indices have been developed that record disease activity, damage and the extent of disease. These validated indices allow a detailed assessment of the patient's response to therapy and provide an essential tool for insuring uniformity of patient monitoring in multi-centre trials. In addition, more data are now available supporting the use of these assessment tools as prognostic and outcome criteria for clinical studies. The development, properties, application and inter-relationships of the available clinical assessment tools for patients with systemic vasculitis are reviewed in this chapter.     

Understanding the lack of understanding: Invalidation from the perspective of the patient with fibromyalgia

Objective

Patients with fibromyalgia have difficulty with the invisibility and medically unexplained character of the syndrome. Disbelief, lack of acceptance, and stigmatization by their spouse, family, colleagues, the health care system, and society are key issues in their lives. Nevertheless, the components of this phenomenon that we term “invalidation” are not clear. The aim of our study was to identify the definition and structure of invalidation as perceived by patients with fibromyalgia.

Methods

A hierarchical cluster analysis was applied to examine everyday invalidation experiences of patients with fibromyalgia. Ninety‐four statements about invalidation that were derived from interviews and a card‐sorting (Q‐sort) technique provided the input for this cluster analysis.

Results

The hierarchical structure of invalidation showed a higher‐order distinction between statements reflecting “discounting” and “understanding.” Discounting was subdivided into the components “denying” and “patronizing” (consisting of “lecturing” and “overprotecting”). Understanding was subdivided into “supporting” and “acknowledging.” These higher‐order constructs were further subdivided into 15 lower‐order clusters that reflected cognitive, affective, and behavioral aspects of invalidation.

Conclusion

Invalidation as perceived by patients with fibromyalgia includes active negative social responses (denying, lecturing, and overprotecting) as well as a lack of positive social responses (supporting and acknowledging) with respect to the patient and the condition of the patient. This definition of invalidation provides a basis to quantify invalidation and to study its impact on symptom severity, quality of life, therapy adherence, therapy outcome, and other important aspects of fibromyalgia.     

Role of Continuous Glucose Monitoring in the Management of Diabetic Pregnancy

Self-monitoring of blood glucose (SMBG) with intermittent capillary glucose fingerstick tests is currently the universally accepted method of glucose monitoring in pregnancy. During pregnancy SMBG tests are recommended before and after meals and before bed (typically 7 values/d). Continuous glucose monitoring systems consist of a disposable subcutaneous glucose-sensing device, electrochemically measuring glucose levels in subcutaneous tissues every 10 seconds, providing an average interstitial glucose value every 5 minutes (typically 288 values/d). From a research perspective this provides unprecedented insights into the pathophysiology of glucose metabolism, while from a clinical perspective it can facilitate enhanced patient-professional decision making, patient motivation, and improved glycaemic control. CGM has thus been described as a “roadmap for effective self-management” and as a “stepping stone in the journey towards a cure.” This review will consider the lessons learned and evidence supporting current and potential future use of CGM in the management of diabetes in pregnancy.     

Respiratory function testing: the impact of respiratory scientists on the training and support of primary health care providers

OBJECTIVE: In rural Australia access to doctors is limited, access to respiratory physicians even more so and these are the traditional sources of lung function testing.The aim of this study was to assess the feasibility of training and supporting existing rural primary healthcare providers in lung function testing as a screening and monitoring mechanism due to the shortage of healthcare professionals capable of providing such a service. METHODOLOGY: As pharmacists are readily accessible healthcare professionals, they were trained in spirometry measurement and supported with ongoing quality assurance by respiratory scientists. Spirometers were provided to the pharmacists. People purchasing respiratory medications or responding to advertising about the service were tested after giving informed consent. Spirometic assessments were assessed for accuracy and reproducibility. Participants' spirometry results were reviewed and those with abnormal test results were referred to their doctor. RESULTS: Pharmacists were able to competently develop the skills necessary for providing spirometry measurement as a screening and monitoring technique. The level of competence exceeded that reported in previously published studies. Pharmacists were able to successfully identify spirometry results within the normal range. CONCLUSIONS: Training and supporting accessible healthcare professionals to provide lung function testing increases access in areas of need and has implications for respiratory morbidity and mortality in such settings.     

Enhancing support via interactive technologies

Despite some improvements in diabetes treatment processes, outcomes for many patients remain inadequate. Interactive health technologies (IHTs) can address many of the challenges that diabetes patients and their health systems face, and research on IHT applications for diabetes care are intensifying. This article describes recent evidence regarding the feasibility and impact of 1) clinic-based CD-ROM systems supporting behavior change; 2) automated telephone diabetes management allowing for ongoing monitoring and patient education between face-to-face clinical encounters; and 3) Web-based systems focusing on a range of diabetes management goals such as enhanced emotional support for patients and improved clinician adherence to treatment guidelines. Studies in each of these areas have been somewhat encouraging. However, intervention effects have been moderate, and researchers face significant challenges in designing and implementing definitive studies.     

Ambulatory ECG-Based T-Wave Alternans Monitoring for Risk Assessment and Guiding Medical Therapy: Mechanisms and Clinical Applications

Identification of individuals at risk for sudden cardiac death (SCD), the main cause of adult mortality in developed countries, remains a major challenge. The main contemporary noninvasive marker, left ventricular ejection fraction (LVEF), has not proved adequately reliable, as the majority of individuals who die suddenly have relatively preserved cardiac mechanical function. Monitoring of T-wave alternans (TWA), a beat-to-beat fluctuation in ST-segment or T-wave morphology, on ambulatory electrocardiogram (AECG) is an attractive approach on both scientific and clinical grounds. Specifically, TWA's capacity to assess risk for malignant arrhythmias has been shown to rest on sound electrophysiologic principles and AECG-based TWA monitoring can be performed in the flow of routine clinical evaluation. This review addresses: (1) electrophysiologic and ionic mechanisms underlying TWA's predictivity, (2) principles and practical aspects of AECG-based TWA monitoring, (3) clinical evidence supporting this approach to SCD risk stratification, and (4) current and potential applications in guiding medical therapy.     

Ultrastructural Changes in Human Platelets During Arachidonic Acid-induced Aggregation

This study was undertaken to visualizethe sequence of ultrastructural changesoccurring in human platelets during aggregation induced by arachidonic acid.Aggregometer recordings were obtainedup to the time of adding glutaraldehydeto begin fixation of platelets for electronmicroscopy. A correlation was shown between the degree of aggregation andchanges in the fine structure of humanplatelets which had been allowed to aggregate for 15, 30, 90, or 180 sec. Thepattern of ultrastructural changes foundin the platelets aggregating in response toarachidonic acid was similar to that reported previously for other aggregatingagents such as collagen or ADP. Amorphous material was observed within thedilated canalicular system of platelets,supporting the thesis that its channelsserve as a pathway for the products released during aggregation. The dilatationof the canalicular system of platelets induced by arachidonic acid could bemediated by an intermediate in prostaglandin synthesis.

Submitted on January 4, 1974 Revised on February 14, 1974 Accepted on February 26, 1974     

Intrathoracic impedance monitoring for early detection of impending heart failure decompensation

In patients with chronic heart failure, detecting signs and symptoms of worsening congestion early enough to prevent hospitalization is an ongoing challenge. Intrathoracic impedance monitoring is a new, device-based method for detecting fluid accumulation in the lungs. Small clinical trials have shown that it may provide an early warning of impending decompensation and may be useful when used in conjunction with routine clinical assessment in guiding diuresis during hospitalization. Additional large-scale, prospective, randomized clinical trials are currently underway to further evaluate its clinical utility. This review discusses the basic concepts underlying intrathoracic impedance monitoring, the clinical evidence supporting its use, and some common pitfalls to avoid when interpreting intrathoracic impedance data.     

Household,family and intergenerational interaction of rural Arab elderly in Israel

The rural Arab elderly in Israel live in a society undergoing rapid social, political and economic change. Family relations, as expressed in intergenerational interaction, are intensive, frequent and mutually supporting, and probably not motivated by the overt needs of the old. The findings on the household history of the investigated population indicate that the establishment of separate household by young couples, at marriage, is not a modern phenomenon. This fact helps to explain the positive attitude toward the single generation household found in this study. The data indicate that family structure and household structure, as well as intergenerational interaction basically have not been affected by the rapid changes occurring in the political and economic structure of the rural areas.This paper is based on study supported by a grant from the Ford Foundation, received through the Israel Foundations Trustees.     

Influence of Loading Conditions on the Mechanical Performance of Multifilament Coreless UHMWPE Sutures Used in Orthopaedic Surgery

This work studies the influence of loading velocity and previous cyclic loading history on the stiffness and strength of a multifilament coreless ultra-high-molecular-weight polyethylene (UHMWPE) surgical suture. Thread samples (n = 8) were subjected to a load-to-failure test at 0.1, 0.5, 1, 5, and 10 mm/s without previous loading history and after 10 cycles of loading at 1–10 N, 1–30 N, and 1–50 N. The experimental data were fitted to mathematical models to compute the stress–strain relation and the strength of the suture. The bilinear model involving two stress–strain ratios for low- and high-strain intervals was the best fit. The ratio in the low-strain range rose with loading speed, showing mean increases of 5.9%, 6.5%, 7.9%, and 7.3% between successive loading speeds. Without a previous loading history, this ratio was less than half than that at high strain. However, 10 cycles of 1–30 N or 1–50 N significantly increased the stress–strain ratio at a low strain level by 135% and 228%, respectively. The effect persisted after 2 min but vanished after 24 h. No influence was found on the suture strength. In conclusion, the stiffness of the studied suture was influenced by the strain level, loading velocity, and recent cyclic loading history. Conversely, the suture strength was not affected.