Liquid Crystalline Network Composites Reinforced by Silica Nanoparticles

Liquid crystalline networks (LCNs) are a class of polymers, which are able to produce mechanical actuation in response to external stimuli. Recent creation of LCNs with exchangeable links (xLCNs) makes LCNs easy moldable. As the xLCNs need to be shaped at a high temperature, it is important to enhance their thermal and mechanical properties. In this paper, a series of xLCNs/SiO₂ composites containing 1%–7% SiO₂ nanoparitcles (SNP) were prepared and their thermal and mechanical properties were examined. The results show that xLCNs/SNP composites have lower liquid crystalline-isotropic phase transition temperature and higher decomposition temperature than pure LCN. The tensile strength and the elongation at break of xLCNs at high temperatures were also enhanced due to the addition of SNPs.     

Effects of Cognitive-Behavioral Therapy on Improving Anxiety Symptoms,Behavioral Problems and Parenting Stress in Taiwanese Children with Anxiety Disorders and Their Mothers

The aims of this intervention study were to examine the effects of individual cognitive-behavioral therapy (CBT) based on the modified Coping Cat Program on improving anxiety symptoms and behavioral problems in Taiwanese children with anxiety disorders and parenting stress perceived by their mothers. A total of 24 children with anxiety disorders in the treatment group completed the 17-session individual CBT based on the modified Coping Cat Program, and 26 children in the control group received the treatment as usual intervention. The Taiwanese version of the MASC (MASC-T), the Child Behavior Checklist for Ages 6–18 (CBCL/6-18) and the Chinese version of the Parenting Stress Index (C-PSI) were applied to assess the severities of anxiety symptoms, behavioral problems and parenting stress, respectively. The effects of CBT on improving anxiety symptoms, behavioral problems and parenting stress were examined by using linear mixed-effect model with maximum likelihood estimation. The results indicated that the CBT significantly improved the severities of MASC-T Physical Symptoms and Social Anxiety subscales, CBCL/6-18 DSM-oriented Anxiety Problem subscale, and C-PSI Child domains Mood and Adaptability subscales. Individual CBT based on the modified Coping Cat Program can potentially improve anxiety symptoms in Taiwanese children with anxiety disorders and some child domains of parenting stress perceived by their mothers.     

The exacerbation of depression,hostility, and social anxiety in the course of Internet addiction among adolescents: A prospective study

Background

In adolescent populations worldwide, Internet addiction is prevalent and is often comorbid with depression, hostility, and social anxiety of adolescents. This study aimed at evaluating the exacerbation of depression, hostility, and social anxiety in the course of getting addiction to Internet or remitting from Internet addiction among adolescents.

Method

This study recruited 2293 adolescents in grade 7 to assess their depression, hostility, social anxiety and Internet addiction. The same assessments were repeated one year later. The incidence group was defined as subjects classified as non-addicted in the first assessment and as addicted in the second assessment. The remission group was defined as subjects classified as addicted in the first assessment and as non-addicted in the second assessment.

Results

The incidence group exhibited increased depression and hostility more than the non-addiction group and the effect of on depression was stronger among adolescent girls. Further, the remission group showed decreased depression, hostility, and social anxiety more than the persistent addiction group.

Conclusions

Depression and hostility worsen in the addiction process for the Internet among adolescents. Intervention of Internet addiction should be provided to prevent its negative effect on mental health. Depression, hostility, and social anxiety decreased in the process of remission. It suggested that the negative consequences could be reversed if Internet addiction could be remitted within a short duration.     

Bilateral maxillary duplication: case report and literature review

Accessory maxillary jaws are extremely rare occurrences. Currently, there is only 1 report of bilateral accessory maxillary jaws in the English-language literature. We present a case of a 7-year-old girl with bilateral bony exostoses extending from the maxillary tuberosities. The patient also had restricted protrusive and lateral excursive movements of the mandible. The histologic report revealed teeth in various developmental stages within the bony exostoses. We concluded that these structures were an isolated form of bilateral accessory maxillary jaws.     

Built environment and mobility of older adults: important policy and practice efforts

As people age, they prefer to "age in place." The concept of aging in place refers to the ability to live in one's own home, wherever that might be, for as long as one can feel confident and comfortable. Where people live and whether these environments can support them are critical questions for public health and public policy, especially since the baby boomers began to turn 65 on January 1, 2011. Equally important for public policy, those aged 85 and older are the fastest growing population group in the United States. The Health and Aging Policy Fellows Program, with the Centers for Disease Control and Prevention Healthy Aging Program, has supported a project to determine how design features of the built environment can support the mobility of older adults. Mobility refers to physical activity, usually walking, but also encompasses the ability to stay connected to nearby community resources and services. The project's purpose is to investigate features that support mobility in built environments. This policy brief introduces the realist synthesis method used in the project and selected national initiatives and activities to place this work in a broader context. Given the importance of mobility concerns to older adults, it must be determined without delay which design features support mobility and how local areas can better prepare to support the health of their aging populations.     

Low Entomological Impact of New Water Supply Infrastructure in Southern Vietnam,with Reference to Dengue Vectors

We did a prospective study in southern Vietnam where new water infrastructure was added. New 1,200-L tanks may present potential breeding grounds for Aedes aegypti, particularly when sealed lids were not always supplied. Some householders in these communes received a piped water supply, however there was no reduction in water storage practices. The prevalence of Aedes aegypti immatures in tank and tap households reached 73%, but were non-significantly different from each other and from control households that received no infrastructure. In all three communes, standard jars comprised from 48% to 71% of containers but were associated with > 90% of III–IV instars and pupae on occasions. In contrast, project tanks contributed from 0–21% of the total population. Non-functional or no lids were apparent 4 months after installation in 45–76% of new tanks, but there was no difference between communes with lids and without lids.     

New nerve regeneration strategy combining laminin-coated chitosan conduits and stem cell therapy

Nerve regeneration remains a difficult challenge due to the lack of safe and efficient matrix support. We designed a laminin (LN)-modified chitosan multi-walled nerve conduit combined with bone marrow stem cell (BMSC) grating to bridge a 10 mm long gap in the sciatic nerve of Sprague–Dawley rats. The repair outcome was monitored during 16 weeks after surgery. Successful grafting of LN onto the chitosan film, confirmed by immunolocalization, significantly improved cell adhesion. In vivo study showed that newly formed nerve cells covered the interior of the conduit to connect the nerve gap successfully in all groups. The rats implanted with the conduit combined with BMSCs showed the best results, in terms of nerve regrowth, muscle mass of gastrocnemius, function recovery and tract tracing. Neuroanatomical horseradish peroxidase tracer analysis of motor neurons in the lumbar spinal cord indicated that the amount and signal intensity were significantly improved. Furthermore, BMSCs suppressed neuronal cell death and promoted regeneration by suppressing the inflammatory and fibrotic response induced by chitosan after long-term implantation. In summary, this study suggests that LN-modified chitosan multi-walled nerve conduit combined with BMSCs is an efficient and safe conduit matrix for nerve regeneration.     

Expression of Oct4 in human embryonic stem cells is dependent on nanotopographical configuration

The fate of adult stem cells can be influenced by physical cues, including nanotopography. However, the response of human embryonic stem cells (hESCs) to dimensionally well-defined nanotopography is unknown. Using imprint lithography, we prepared well-defined nanotopography of hexagonal (HEX) and honeycomb (HNY) configurations with various spacings between the nanostructures. In serum-free hESC culture medium, basic fibroblast growth factor (bFGF) is required to maintain expression of Oct4, a pluripotent gene. Unexpectedly, hESCs cultured on nanotopography could maintain Oct4 expression without bFGF supplementation. With bFGF supplementation, the HEX nanotopography maintained Oct4 expression whereas the HNY configuration caused down-regulation of Oct4 expression. Thus, we observed that the lattice configurations of the nanotopography cause hESCs to respond to bFGF in different ways. This differential response to a biochemical cue by nanotopography was unforeseen, but its discovery could lead to novel differentiation pathways. Consistent with studies of other cells, we observed that nanotopography affects focal adhesion formation in hESCs. We posit that this can in turn affect cell–matrix tension, focal adhesion kinase signaling and integrin–growth factor receptor crosstalk, which eventually modulates Oct4 expression in hESCs.