Cell Compatible Electrospun Poly(vinyl alcohol) Fibers for Tissue Regeneration

Poly(vinyl alcohol) (PVA) is a well known biocompatible synthetic polymer. PVA is not cell compatible due to its high hydrophilicity. As prepared by electrospinning in the form of nanofibers, it is unstable in aqueous environments including cell culture media. For tissue regeneration applications, this study demonstrates the use of PVA scaffold utilizing electrospun nanofibers with aqueous stability and cell compatibility toward creating biomaterial-tissue hybrid based medical devices. Two different approaches: heat treatment and ion beam treatment were developed to improve aqueous stability and promote cell compatibility for PVA fibers. Using a thermal annealing method at elevated temperatures, the fibers became stable in water. This observation correlated closely to the change in the crystallinity of PVA. Elastic moduli of individual fibers were determined using a multi-points bending approach by atomic force microscopy. Elastic moduli of as-spun PVA fibers were determined to be a function of fiber diameter and humidity. Significant changes in the elastic modulus of the modified PVA fibers were also observed. To improve the cell compatibility, low energy N+ and He+ ion beams were used to introduce amine and carbonyl functional groups. Cell compatibility was assessed in vitro using primary human skin fibroblasts (hsF). Confocal microscopy confirmed the adhesion and proliferation of hsF on both the random and aligned PVA fibers after the ion beam treatment, while cells failed to adhere to the untreated fibers. Cell morphology was observed to align and elongate along the fiber axis on aligned PVA fibers. After 10 days of proliferation, cells were found to form confluent layers and even multiple layers on the N+treated fibers. Cell proliferation depends on ion species, ion dose and fiber alignment. With the two post-processing treatments, PVA fibrous scaffold showed the potential to become biomaterial-tissue hybrid based medical devices for tissue regeneration applications

Static Balancing Control of Humanoid Robot based on Accelerometer

[[abstract]]A static balancing control method is proposed and implemented on a humanoid robot so that the robot can stand and balance on a plane. A small-size humanoid robot named TWNHR-IV with 26 degree-of-freedom (DOF) is implemented. A 3-axis accelerometer is installed on TWNHR-IV to obtain the x-axis, y-axis, and z-axis accelerations of TWNHR-IV. Based on the obtained information from the 3-axis accelerometer, a system structure with two two-input-and-one-output fuzzy systems is proposed. The acceleration and the accelerationpsilas variation of the x-axis obtained by the 3-axis accelerometer are considered to be the inputs of forward-and-backward fuzzy system. The acceleration and the accelerationpsilas variation of the y-axis are considered to be the inputs of right-and-left fuzzy system. Some practical tests are presented to illustrate the proposed method can let the humanoid robot stand and balance on a plane.[[conferencetype]]國際[[conferencelocation]]Tokyo, Japa

Influence of chemical treatment on the recycling of composites before pyrolysis

Recycling of carbon fibers is one of the upcoming global research topics in composite engineering. This work investigates the influence of chemical treatment on the recovery of carbon fibers from carbon fiber reinforced plastic before pyrolysis. The chemical pretreatment was achieved using a zinc chloride/ethanol solution. The pyrolysis process was conducted in a sliding furnace. The effect of such pre-treatment on thermal degradation behaviour was determined by a thermogravimetric analyser (TGA). An original sample was also investigated for benchmarking. After the thermal pyrolysis process, the fiber tensile properties were measured using a single fiber tester. The surface functional groups and graphitization degree recovered carbon fiber were characterized using X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The surface morphology of recycled carbon fibers was investigated by SEM. Pristine carbon fibers were also included in the study for benchmarking. During the pyrolysis process, the devolatilisation temperature of the pre-impregnated prepregreduced by around 40-50°C and the peak temperature was 40-50°C lower compared to that of the original prepreg. The chemical pre-treatment process reduces the pyrolysis temperature compared to the conventional pyrolysis process. After pyrolysis in nitrogen with a small amount of air, loose carbon fibers were recovered, and their surface was clean. The similar surface functional groups and the decrease of degree of graphitization were detected on the recycled carbon fiber

Shredding energy consumption of GFRP composite waste

This work investigated effect of glass fibre fabric structures, feedstock feed rate and screen size on specific shredding energy of glass fibre reinforced plastics (GFRP) waste via a two-level factorial design of experiment study. Four types of fabric structure, i.e. unidirectional (UD), biaxial (BIAX), triaxial (TRIAX) and chopped strand mat (CSM), were impregnated separately with unsaturated polyester resin to manufacture GFRP plates. The shredding energy was measured using a two-wattmeter approach. During shredding, CSM demonstrated a relatively flat power consumption curve compared to other fabric types. It was also noticed that the GFRP plate reinforced with more complex woven structure, i.e. TRIAX, required higher energy for shredding, especially with a combination of high feed rate and small screen size. It was found that mechanical efficiency was only around 8.2-15.7% and 0.8-2.2% for shredding at feed rate of 60 kg/hr and 10 kg/hr respectively. It was also found that adopting a larger screen size and lower feed rate could reduce the specific shredding energy

Non-prescription ophthalmic pharmaceutical agents for the prevention or relief of eye irritations in swimming

Non-prescription ophthalmic pharmaceutical agents for the prevention or relief of eye irritations in swimmin

J Interpers Violence

Homicide-suicide incidents involving child victims can have a detrimental impact on survivors of the violence, family members and friends of the decedents, and other community members, but the rare occurrence of these acts makes using quantitative data to examine their associated antecedents challenging. Therefore, using qualitative data from the 2003-2011 National Violent Death Reporting System, we examined 175 cases of homicide-suicide involving child victims in an effort to better understand the complex situational factors of these events. Our findings indicate that 98% of homicide-suicides with child victims are perpetrated by adults (mostly parents) and propelled by the perpetrators' intimate partner problems, mental health problems, and criminal/legal problems. These events are often premeditated, and plans for the violence are sometimes disclosed prior to its occurrence. Findings provide support for several theoretical perspectives, and implications for prevention are discussed.CC999999/Intramural CDC HHS/United States2019-02-01T00:00:00Z26385898PMC4795978vault:1634

Having a family doctor is associated with some better patient-reported outcomes of primary care consultations

<b>Background</b> Hong Kong (HK) has pluralistic primary care that is provided by a variety of doctors. The aim of our study was to assess patient-reported outcomes of primary care consultations in HK and whether having a family doctor (FD) made any difference.<p></p> <b>Methods</b> We interviewed by telephone 3148 subjects from 5174 contacted households (response rate 60.8%) randomly selected from the general population of HK about the experience of their last primary care consultations in September 2007 and April 2008. We compared the patient-reported outcomes (PRO) and patient-centered process of care in those with a FD, those with other types of regular primary care doctors (ORD) and those without any regular primary care doctor (NRD). PRO included patient enablement, global improvement in health, overall satisfaction, and likelihood of recommending their doctors to family and friends. Patient-centered process of care indicators was explanations about the illness, and address of patient’s concerns.<p></p> <b>Results</b> One thousand one hundred fifty, 746, and 1157 reported to have FD, ORD, and NRD, respectively. Over 80% of those with FD consulted their usual primary care doctors in the last consultation compared with 27% of those with NRD. Compared with subjects having ORD or NRD, subjects with FD reported being more enabled after the consultation and were more likely to recommend their doctors to family and friends. Subjects with FD and ORD were more likely than those having NRD to report a global improvement in health and satisfaction. FD group was more likely than the other two groups to report receiving an explanation on the diagnosis, nature, and expected course of the illness, and having their concerns addressed. Patient enablement was associated with explanation of diagnosis, nature, and expected course of illness, and address of patient’s concerns.<p></p> <b>Conclusion</b> People with a regular FD were more likely to feel being enabled and to experience patient-centered care in consultations

Energy and system dependence of high-pTp_T triggered two-particle near-side correlations

Previous studies have indicated that the near-side peak of high-$p_T$ triggered correlations can be decomposed into two parts, the \textit{Jet} and the \textit{Ridge}. We present data on the yield per trigger of the \textit{Jet} and the \textit{Ridge} from $d+Au$, $Cu+Cu$ and $Au+Au$ collisions at $\sqrt{s_{NN}}$ = 62.4 GeV and 200 GeV and compare data on the \textit{Jet} to PYTHIA 8.1 simulations for $p+p$. PYTHIA describes the \textit{Jet} component up to a scaling factor, meaning that PYTHIA can provide a better understanding of the \textit{Ridge} by giving insight into the effects of the kinematic cuts. We present collision energy and system dependence of the \textit{Ridge} yield, which should help distinguish models for the production mechanism of the \textit{Ridge}.Comment: 4 pages, 6 figures, proceedings for Hot Quarks in Estes Park, Colorad