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Layer by Layer (LbL) deposition is a simple and inexpensive method of multilayer self-assembly, that relies on the electrostatic interactions of oppositely charged polyelectrolytes. Functional biopolymers used to build such nanostructured multilayers can keep serving their inherent functions in food systems. A good example is chitosan, a positively charged biopolymer which has antimicrobial properties and forms stable complexes with negatively charged polymers. This study investigates the potential of commercially available food grade biopolymers to substitute synthetic polyelectrolytes when building nanostructured multilayers. Chitosan molecular weight, carrageenan charge density and pectin degree of esterification and amidation was varied to investigate their respective effects on the nanoscale morphology and wettability of these surfaces. Extracellular Ice Nucleators (ECINs), functional lipoglycoproteins of negative charge known to increase ice nucleation temperatures in food systems, were used to confirm the suitability of biopolymer multilayers for fabricating functional food grade nano-thin films. High molecular weight chitosan and iota-carrageenan created the most appropriate biopolymer pair to serve this purpose, as demonstrated by the nanoscale evaluation of these ultra-thin layers. ECINs successfully adsorbed onto the multilayer system, and ice nucleation activity of the nano-thin film was confirmed via the cooling bath experiments. [ABSTRACT FROM AUTHOR]

Summary: Objective: To investigate usefulness of osteochondral grafting from the costo-osteochondral junction as a repair technique for articular cartilage defects histologic and biochemical analysis of grafted cartilage in rabbit knees was evaluated up to 48weeks after transplantation. Methods: Twenty New Zealand White rabbits were used. A costal osteochondral plug was harvested from a middle rib. After trimming, it was transplanted into a cylindrical osteochondral 2.5mm diameter and 5mm deep defect created in the knee. The animals were sacrificed at 6, 12, 24, and 48weeks after transplantation. Defect sites were inspected macroscopically, and then by light microscopy. Samples were evaluated for cell viability using a fluorescent in situ double-staining protocol with confocal laser microscopic analysis. Samples were also processed to assess type I & II collagen and aggrecan mRNA expression using reverse transcription-polymerase chain reaction (RT-PCR). Results: Histologically, bone union was achieved in all plugs. Confocal microscopic analysis revealed chondrocyte viability in the 48-week grafts; the distribution of chondrocytes was similar to surrounding articular cartilage. The expression of type II collagen and aggrecan mRNA in the grafted cartilage was consistent with normal articular cartilage and normal costal cartilage. These results were observed over 6–48weeks. Conclusions: Our study revealed that chondrocytes in the grafted cartilage were viable at least up to 48weeks and that mRNA expression of type II collagen and aggrecan was also similar to that of normal articular cartilage. These results suggest that costal osteochondral grafting can be a useful alternative in the treatment of osteochondral defects. [ABSTRACT FROM AUTHOR]

Summary: There are few data concerning changes in lung function and respiratory symptoms in smokers with chronic obstructive pulmonary disease (COPD) weeks to months after quitting smoking. We examined serial changes in spirometry and Clinical COPD Questionnaire (CCQ) scores (measuring respiratory symptoms and health-related quality of life) in COPD participants by smoking status during a smoking cessation trial. In this randomized, double-blind trial, smokers with mild-to-moderate COPD were treated with varenicline 1 mg b.i.d. or placebo for 12 weeks and followed to Week 52. Primary endpoints of abstinence were previously reported. Secondary endpoints were mean changes from baseline in post-bronchodilator forced expired volume in 1 s (FEV1) and CCQ scores. Change from baseline in post-bronchodilator FEV1 was significantly improved in continuous abstainers (121.8 mL) vs. continuous smokers (37.9 mL) at Week 12 (P = 0.0069), but not at Weeks 24 or 52. Mean change from baseline at Week 12 in CCQ Total Score was significantly better in continuous abstainers (−1.04) vs. continuous smokers (−0.53; P < 0.0001): this improvement was sustained at Weeks 24 and 52. In a 1-year cessation trial of smokers with COPD, continuous abstinence compared with continuous smoking significantly improved post-bronchodilator FEV1 at Week 12 (although the difference narrowed subsequently) and CCQ Total Scores at Week 12, with sustained improvement thereafter. (Trial registry: http://www.clinicaltrials.gov; trial identifier: NCT00285012) [Copyright &y& Elsevier]

Abstract: The exact positional and total orientation workspaces of a hexapod parallel mechanism are three-dimensional volumes that are too complicated for an operator to make use of, but a knowledge of them is indispensable in order to avoid collisions with the environment and to locate the workpiece. Fortunately, the positional and total orientation workspaces of a symmetric simplified architecture (the SSM type) can be bounded from inside and outside by ellipsoids symmetric about the z-axis. Accordingly, this paper presents closed-form solutions for the radii of the inscribed and circumscribed circles of the positional workspace and approximate solutions for the total orientation workspace at any given height. These solutions can be plotted on a two-dimensional graph that is convenient for an operator on the shop floor. Furthermore, these solutions can be developed into a simple procedure for the design of a prescribed workspace. [Copyright &y& Elsevier]

Abstract: The increasing application of numerical simulation in the field of metal forming has helped engineers to solve problems one after another to manufacture a qualified formed product in a reduced time. Accurate simulation results are vital for die and product designs. Many factors can influence the final simulation result, the most important of which is a suitable yield criterion. The proposed Forming Limit Curve (FLC), which is used to evaluate the necking risk, differs a lot while different yield criteria used. In this study, the theoretical FLC is calculated using Swift model, which considers three-yield criteria Hill 48, Hill 90 and Hill 93. Also, the simulation processes with two yield criteria, Hill 48 and Hill 90, are carried out with two types of material, SPCC (JIS G3141) and Al6xxx. The strain evolutions of elements located in two trajectories of two materials are investigated and compared. The simulation results are compared with the experimental ones to evaluate the effectiveness of the yield criterion. [Copyright &y& Elsevier]

This paper describes a novel approach to the theoretical prediction of fatigue damage and failure in bone. A simulation was set up in which the growth of every crack in the material was described individually. A modified fracture-mechanics equation was used to describe crack growth, using stochastic variables to simulate scatter. This model was cumbersome to set up initially, having a large number of degrees of freedom, but it proved to be capable of predicting a wide variety of experimental data, including: crack density, length and other damage variables; stress/life data, and the effect of specimen size. It was also possible to simulate the increased density of cracks that occurs in older people. Explicit models of this kind, which include the underlying mechanisms of the process, are more useful in the long term because they can be extended to include other mechanisms, in this case the processes by which living bones can repair cracks, and adapt their shapes to altered stress levels. [Copyright &y& Elsevier]

In the past few decades, considerable efforts have been devoted to the phenomenon of wave-seabed interaction. However, conventional investigations for determining wave characteristics have been focused on the wave nonlinearity. On the other hand, most previous works have been only concerned with the seabed response under the wave pressure, which was obtained from the assumption of a rigid seabed. In this paper, the inertia forces and employing a complex wave number are considered in the whole problem. Based on Biot’s poro-elastic theory, the problem of wave-seabed interaction is first treated analytically for a homogeneous bed of finite thickness and a new wave dispersion relationship is also obtained, in which the soil characteristics are included. The numerical results indicate that the effects of soil parameters significantly affect the wave characteristics (such as the damping of water wave, wave length and wave pressure). Furthermore, the effects of inertia forces on the wave-induced seabed response cannot always be ignored under certain combination of wave and soil conditions. [Copyright &y& Elsevier]

This research employed a qualitative approach to discuss the current practice and challenges of Malaysian manufacturing firms in the implementation of Industry 4.0. The study examined data from seven manufacturing companies pursuing Industry 4.0 initiatives to identify various options for their strategies. The study found that the implementation of Industry 4.0 in the manufacturing firms is still in the exploratory stage. The companies involved in this study were discovered to conduct exploration using an adaptive-like framework. That is, throughout the process, the majority of the subjects are 'trying and adding' Industry 4.0 to their operations. Their trial-and-error approach is based on what is feasible and effective in their manufacturing environment. Overall, the investigation determined that data management and integration, as well as personnel re-education, were the respondents' primary operational challenges. • Current practice and challenges in Malaysian manufacturing firms in the implementation of Industry 4.0 are discussed. • The most recent implementation of Industry 4.0 in Malaysia is still at an early stage. • Data management and integration as well as re-education were found as the main challenges. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Pancreatic islet transplantation (PIT) has only become an effective treatment for type 1 diabetes mellitus within the past 4 years. As a result, the long-term effects of PIT on progression of diabetic neuropathy and retinopathy are unknown. The benefit of halting or improving diabetic neuropathy and retinopathy is of particular interest since most PIT recipients have not developed the advanced complications of diabetes. Herein, we describe the improvement and stabilization of diabetic neuropathy and retinopathy in 12 PIT recipients. Patients and methods: Between January 1, 2002, and June 30, 2004, there have been 12 patients who have received PIT. Currently, there are eight patients who have sufficient follow-up to assess the progression of diabetic retinopathy and neuropathy. To assess for disease progression, patients were examined by a single ophthalmologist and single neurologist throughout the study period. Eye exams were performed using a slit-lamp exam while neurological status was assessed using electromyelograms and clinical exams. Results: All PIT recipients had decreases in hemoglobin A1C and increases in serum C-peptide. All study patients had stabilization of their retinopathic disease. One patient demonstrated improvement of retinopathy at 1 year posttransplant. Fifty percent of patients demonstrated improvement or stabilization of their diabetic neuropathy. One patient had mild reinnervation of the fingers and wrist extensors by clinical exam 1 year posttransplant. Four patients exhibited an average decrease of 19% in sural nerve conduction velocities. Conclusion: Our series has demonstrated that all PIT recipients have had stabilization of their diabetic retinopathy and that 50% of patients exhibited stabilization or even improvement of their diabetic neuropathy. [Copyright &y& Elsevier]