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Background: Indigenous populations globally are disproportionately affected by chronic hepatitis B virus (HBV) infection however contemporary sero-prevalence data are often absent. In the Indigenous population of the Northern Territory (NT) of Australia the unique C4 sub-genotype of HBV universally circulates. There are no studies of the sero-prevalence, nor the impact of the vaccination program (which has a serotype mismatch compared to C4), at a population-wide level. Methods: We examined all available HBV serology results obtained from the three main laboratories serving NT residents between 1991 and 2011. Data were linked with a NT government database to determine Indigenous status and the most recent test results for each individual were extracted as a cross-sectional database including 88,112 unique individuals. The primary aim was to obtain a contemporary estimate of HBsAg positivity for the NT by Indigenous status. Results: Based on all tests from 2007–2011 (35,633 individuals), hepatitis B surface antigen (HBsAg) positivity was 3·40% (95%CI 3·19–3·61), being higher in Indigenous (6·08%[5·65%-6·53%]) than non-Indigenous (1·56%[1·38%-1·76%]) Australians, p<0·0001. Birth cohort analysis showed HBsAg positivity fell over time for Indigenous people, with this decrease commencing prior to universal infant vaccination (which commenced in 1990), with an ongoing but slower rate of decline since 1990, (0·23% decrease per year versus 0·17%). Conclusions: HBsAg positivity is high in the NT, particularly in the Indigenous population. HBsAg positivity has fallen over time but a substantial part of this decrease is due to factors other than the universal vaccination program. [ABSTRACT FROM AUTHOR]

Objective: To investigate trends in hospital admissions involving suicidal behaviour in the Northern Territory (NT) resident population over the period 2001-2013.Methods: Estimates of age-standardised rates and average changes in the annual rate of hospital admissions involving suicidal behaviour were calculated by socio-demographic characteristics and types of suicidal behaviour.Results: Overall rates for Indigenous admissions were 2.7 times higher than non-Indigenous admissions and had increased by almost twice as much. While male and female rates of admission were similar for both Indigenous and non-Indigenous residents, the average annual change in rates was greater for Indigenous females (13.4%) compared to males (8.8%) and for non-Indigenous males (7.7%) compared to females (5.2%). Younger and middle-aged Indigenous admissions experienced increasing rates of admissions, whilst trends were similar across age groups for non-Indigenous admissions. Admissions with a diagnosis of suicidal ideation increased the most across all groups. Trends in intentional self-harm admissions differed according to Indigenous status and sex.Conclusions: There have been substantial increases in hospital admissions involving suicidal behaviour in the NT, most markedly for Indigenous residents. Indigenous females and youth appear to be at increasing risk. The steep increase in suicidal ideation across all groups warrants further investigation. [ABSTRACT FROM AUTHOR]

Inspection for energy consumption and pollution of logistics system involves green evaluation, optimization and management, therefore the deployment of monitors for green logistics in distributed OD carrier network is studied in the paper, and a green-track inspection system and its layout optimization upon the OD carrier network are further proposed. Meanwhile, a mixed integer programming model is established, based on the consideration of monitor coverage quantity and line correlation, and an OD flow shortest path algorithm in distributed OD carrier network is designed. For the limited investment of monitoring equipments, a feasible alternative solution is proposed with promising economic costs and environmental benefits. The model and algorithm are verified through simulation experiments, and some new research opportunities are analyzed. [ABSTRACT FROM AUTHOR]

Background: The prevalence, genotypes, and vertical transmission characteristics of human papillomavirus (HPV) among pregnant women from Nanjing, China was investigated. Methods: Cervical cells were collected from healthy pregnant women (n = 3139; stage of gestation, 24.6 ± 2.1 weeks) for cytological evaluation and determination of HPV infection status. Exfoliated oral and genital cells were collected from neonates (<1-day-old, n = 233) whose mothers were positive for HPV DNA. We used HPV Gene Chip technology with 23 HPV genotype probes to conduct our analysis. Results: Overall prevalence of HPV DNA among pregnant women was 13.4% (422/3139). The most frequently detected HPV genotypes were HPV-16 (29.6%, 125/422), -18 (14.7%, 62/422), and -58 (14.2%, 60/422). The rate of concordance for HPV DNA in maternal-neonatal pairs was 23.6% (55/233), with HPV type-specific concordance occurring in 26 cases. A higher prevalence of HPV DNA was apparent in female neonates compared with males (17.7 vs. 11.6%). Conclusions: The prevalence of cervical HPV DNA in pregnant women from Nanjing was low, with vertical transmission rates slightly higher. From our findings, we concluded that there was efficient vertical transmission of three HPV genotypes, with HPV-16 the most prevalent type in pregnant women and newborn babies. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWNTs) were modified by triethlene-tetramine (TETA) in order to attain better dispersibility and stronger interfacial bonding between MWNTs and epoxy matrix. The influence of surface treated MWNTs on the cure behavior of the diglycidyl ether of bisphenol A (DGEBA)/2-ethyl-4-methyl imidazole (EMI-2,4) system was investigated with nonisothermal differential scanning calorimetry. It was found that the curing peak temperature (TP) decreased with the addition of TETA-MWNTs. The curing apparent activation energy (Ea) was calculated through Kissinger method. In addition, the thermal behavior of TETA-MWNTs/DGEBA/EMI-2,4 was examined by thermogravimetric analysis, and the result showed the addition of TETA-MWNTs could increase the thermal decomposition onset temperature (TB) and the degradation peak temperature (Tmax) of the nanocomposites. Scanning electron microscopy images of fractured surface of MWNTs/epoxy indicated homogeneous dispersibility of TETA-MWNTs and strong interfacial adhesion between the TETA-MWNTs and the epoxy matrix in the nanocomposites. [ABSTRACT FROM AUTHOR]

Cyclooxygenases-2 (COX-2) in the spinal dorsal horn is up-regulated and plays an important role in pain and hyperalgesia induced by nociceptive stimulation. The mechanisms involved in the up-regulation of spinal COX-2 during nociceptive stimulation are yet not well understood. Because the important role of NMDA and its receptor in transmission of nociceptive information in the spinal cord, activation of the spinal NMDA receptor might contribute to the up-regulation of spinal COX-2 expression. The present study was undertaken to demonstrate the above hypothesis by observing changes of COX-2 expression in the spinal dorsal horn in rats subjected to formalin test and intrathecal administration of NMDA, a selective NMDA receptor agonist, in conditions with or without presence of MK-801, an antagonist of NMDA receptor, using methods of Western blotting, reverse transcription polymerase chain reaction and immunohistochemistry. The results showed that intrathecal injection of MK-801, a noncompetitive antagonist of NMDA receptor, significantly suppressed the up-regulation of the COX-2 expression and characteristic pain behavior responses evoked in formalin test. Whereas, intrathecal injection of NMDA significantly up-regulated the expression of COX-2 in the spinal dorsal horn in a time course corresponding to that of nociceptive behavioral responses elicited by the intrathecal NMDA administration. In addition, the up-regulation of the COX-2 expression induced by the intrathecal NMDA was dose-dependent and blocked by prior administration of MK-801. These findings proved that activation of NMDA receptor is associated with the up-regulation of COX-2 expression in the spinal dorsal horn during nociceptive stimulation in rats. [ABSTRACT FROM AUTHOR]

Abstract: The effects of inhibitor K-23 on variable fluorescence, oxygen evolution and DCIP photoreduction were investigated. K-23 promotes the oxygen evolution and DCIP photoreduction at low concentration and inhibits them at relatively high concentrations, while an efficient inhibition at low concentration is found in variable fluorescence. These data further confirm that the inhibitor K-23 action is based on its redox interaction rather than quenching effect. Addition of DPC could not restore the DCIP photoreduction activity. It is suggested that the inhibitory site is at the acceptor side. Using ferricyanide as electron acceptor, the effect of K-23 and DCMU on the oxygen evolution of trypsin-treated thylakoids was investigated. It is found that oxygen evolution of trypsin-treated thylakoids was insensitive to DCMU, whereas became more sensitive to K-23 and also the promotion of K-23 at low concentration disappeared. This strongly indicates that trypsin treatment modified the binding site of K-23 and increased its accessibility to K-23 target site. From the comparison of K-23 with DCMU, we conclude that the binding site of K-23 is different from that of DCMU even though they both bind at the acceptor side. [Copyright &y& Elsevier]

Background: To examine the association between delay in planned diabetes care and quality of outcomes.Methods: A retrospective analysis of primary care and inpatient records for 2567 Aboriginal patients, with diabetes, living in 49 remote communities in the Northern Territory of Australia. Poisson regression was used to estimate the association between delay from diagnosis to documented diabetes care plan and three outcome measures: mean HbA1c level, most recent blood pressure and number of diabetes-related hospital admissions.Results: Compared with no delay (< 60 days), patients with delay had increased risk of elevated mean HbA1c: 60 days to < 2 years, incidence rate ratio (IRR), 1.2 (95% CI:1.07-1.39); 2 years to < 4 years, incidence rate ratio (IRR), 1.2 (95% CI:1.04-1.45); 4 years and over, incidence rate ratio (IRR), 1.3 (95% CI:1.12-1.52). There was no evidence of association between delay and optimal blood pressure control. Risk of diabetes-related admission increased with increased delay. Compared with no delay the IRRs for delay were: 60 days to < 2 years, 1.2 (95% CI:1.07-1.42); 2 to < 4 years, 1.3 (95% CI: 1.15-1.58): and 4 years and over, 2.6 (95% CI,2.28-3.08).Conclusion: The study found that a timely diabetes care plan was associated with better short-term blood glucose control and fewer diabetes-related admissions but not with improved blood pressure control. Delays may be a result of both patient and service-related factors. [ABSTRACT FROM AUTHOR]

Highlights • DPCPX dose-dependently blocked the brain ischemic tolerance of rats induced by LIP. • DPCPX blocked the up-regulation of p38 MAPK and ERK of rats induced by LIP. • Adenosine could induce the brain ischemic tolerance of rats. • Adenosine up-regulates the expression of p38 MAPK and ERK of rats. Abstract Our previous studies have demonstrated that limb ischemic preconditioning (LIP) induced brain ischemic tolerance and up-regulated the expression of p38 MAPK and ERK in the hippocampal CA1 region in rats. The present study was undertaken to investigate the role of adenosine in brain protection and up-regulation of p38 MAPK and ERK induced by LIP. It was found that adenosine A1 receptor antagonist DPCPX dose-dependently inhibited the protective effect of LIP. The up-regulation of p38 MAPK and ERK induced by LIP could be blocked by DPCPX. Furthermore, we observed the effect of adenosine on the brain ischemia. The results showed that pre-administration of adenosine could partly mimic the neuroprotective effect on the brain, up-regulate the expression of p38 MAPK and ERK. Based on the above results, it can be concluded that adenosine participated in brain protection and up-regulation of the expression of p38 MAPK and ERK during the induction of brain ischemic tolerance after LIP. [ABSTRACT FROM AUTHOR]

Background: The prevalence, genotypes, and vertical transmission characteristics of human papillomavirus (HPV) among pregnant women from Nanjing, China was investigated.Methods: Cervical cells were collected from healthy pregnant women (n = 3139; stage of gestation, 24.6 ± 2.1 weeks) for cytological evaluation and determination of HPV infection status. Exfoliated oral and genital cells were collected from neonates (<1-day-old, n = 233) whose mothers were positive for HPV DNA. We used HPV Gene Chip technology with 23 HPV genotype probes to conduct our analysis.Results: Overall prevalence of HPV DNA among pregnant women was 13.4% (422/3139). The most frequently detected HPV genotypes were HPV-16 (29.6%, 125/422), -18 (14.7%, 62/422), and -58 (14.2%, 60/422). The rate of concordance for HPV DNA in maternal-neonatal pairs was 23.6% (55/233), with HPV type-specific concordance occurring in 26 cases. A higher prevalence of HPV DNA was apparent in female neonates compared with males (17.7 vs. 11.6%).Conclusions: The prevalence of cervical HPV DNA in pregnant women from Nanjing was low, with vertical transmission rates slightly higher. From our findings, we concluded that there was efficient vertical transmission of three HPV genotypes, with HPV-16 the most prevalent type in pregnant women and newborn babies. [ABSTRACT FROM AUTHOR]

A series of poly(polyethylene glycol n -alkyl ether vinyl ether)s (PC m E n VEs) with various lengths of alkyl chains and polyethylene glycol spacers as side chain (m = 16,18; n = 1,2) were synthesized via two steps. First, monomers-ethylene glycol hexadecyl ether vinyl ether (C 16 E 1 VE), ethylene glycol octadecyl ether vinyl ether (C 18 E 1 VE), diethylene glycol hexadecyl ether vinyl ether (C 16 E 2 VE) and diethylene glycol octadecyl ether vinyl ether (C 18 E 2 VE) were synthesized by a modified Williamson etherification. Then, four new types of phase change materials were successfully fabricated by a living cationic polymerization. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) were employed to characterize their composition, thermal properties and crystallization behavior. The results show that, the side chains of PC 16 E 1 VE, PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are in a hexagonal lattice, and the onset temperatures for melting of PC 16 E 1 VE, PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are 39.8 °C, 37.4 °C, 51.0 °C and 48.9 °C, the onset temperatures for crystallization are 36.7 °C, 35.2 °C, 47.4 °C and 46.3 °C, respectively. The enthalpy changes of PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are higher than 100 J/g; on the contrary, it is 96 J/g for PC 16 E 1 VE. The enthalpy decrease is no more than 11% after 10 heating and cooling cycles. The 5 wt% mass loss temperatures of PC 18 E 1 VE, PC 16 E 2 VE and PC 18 E 2 VE are higher than 300 °C; on the contrary, it’s 283 °C for PC 16 E 1 VE. Using a weak polarity, flexible alkyl ether chain (-OCH 2 CH 2 O-) as a spacer to link the main chain and side chain is conducive to the crystallization of the alkyl side chain. These new phase change materials can be applied in heat storage, energy conservation, and environmental protection. [ABSTRACT FROM AUTHOR]

Microglia and astrocytes in the brain play an important role in the development and progression of Alzheimer's disease (AD). Serum amyloid A (SAA) is a major acute-phase protein produced locally in the brain and colocalizes with senile plaques in AD patients. We investigated whether SAA plays a role in the development of AD. The viability of cultured primary microglia and astrocytes was measured by MTT; cell cycle and apoptosis analysis was also conducted. Cultured microglia and astrocytes were stimulated with 1 μM SAA for different periods of time (2, 4, 6, 12 h) or treated with 1 μM SAA with or without 15 min pretreatment of MAPK or PI3K inhibitors. Total RNA was extracted for qPCR analysis. SAA induced morphological changes of primary microglia but not astrocytes. Interestingly, SAA increased the viability of microglia by inhibiting their apoptosis and reduced the viability of astrocytes by inducing G1 cell cycle arresting. SAA treatment increased the mRNA levels of IL-6, TNF-α, IL12p40, IL23p19, and IL-10, with higher potency in microglia than in astrocytes. However, SAA induced more iNOS mRNA in astrocytes than in microglia. SAA induced these cytokines and iNOS expression by activating the PI3K pathway in both glial cells, but selectively activated the JNK pathway in microglia and the NF-κB pathway in astrocytes. These results suggest that SAA can stimulate a different reactive phenotype in microglia and astrocytes, and SAA regulates cell viability differently in these two glial cells in part through the PI3K pathway. [ABSTRACT FROM AUTHOR]

Abstract: Background: A universal newborn hepatitis B (HBV) vaccination program was introduced in the Northern Territory of Australia in 1990, followed by a school-based catch-up program. We evaluated the prevalence of hepatitis B infection in birthing women up to 20 years after vaccination and compared this to women born before the programs commenced. Methods: A cohort of birthing mothers was defined from Northern Territory public hospital birth records between 2005 and 2010 and linked to laboratory confirmed notifications of chronic HBV, based principally on a record of hepatitis B surface antigen detection. Prevalence of HBV was compared between women born before or after implementation of the newborn and catch-up vaccination programs. Findings: Among 10797 birthing mothers, 138 (1.3%) linked to a chronic HBV record. HBV prevalence was substantially higher in Aboriginal women compared to non-Indigenous women (2.4% versus 0.04%; p <0.001). Among 5678 Aboriginal women, those eligible for catch-up and newborn HBV vaccination programs had a significantly lower HBV prevalence than older women born prior to the programs: HBV prevalence respectively 2.2% versus 3.5%, (OR 0.61, 95%CI 0.43–0.88) and 0.8% versus 3.5% (OR 0.21, 95%CI 0.11–0.43). This represents a risk reduction of respectively 40% and 80% compared to unvaccinated women. Interpretation: The progressively greater reduction in the prevalence of chronic HBV in adult Aboriginal women co-inciding with eligibility for catch-up and newborn vaccination programs is consistent with a significant impact from both programs. The use of data derived from antenatal screening to track ongoing vaccine impact is applicable to a range of settings globally. [Copyright &y& Elsevier]

In this work, we report the reorientation of magnetization by spin–orbit torque (SOT) in YIG/Pt bilayers. The SOT is investigated by measuring the spin Hall magnetoresistance (SMR), which is highly sensitive to the direction of magnetic moment of YIG. An external in-plane rotating magnetic field which is applied to the YIG/Pt bilayers, and the evolutions of SMR under different injected currents in the Pt layer, result in deviation of SMR curve from the standard shape. We conclude that the SOT caused by spin accumulation near the interface between YIG and Pt can effectively reorient the in-plane magnetic moment of YIG. This discovery provides an effective way to modulate YIG magnetic moments by electrical methods. [ABSTRACT FROM AUTHOR]

Redressing developmental and school learning inequalities among children requires an understanding of the factors that influence development across population groups. This study utilized the 2009 Australian Early Development Census (AEDC) to explore the association of perinatal health and socio-demographic factors with early development of children in the Northern Territory of Australia. The study cohort included 1110 Aboriginal and 812 non-Aboriginal children, most aged 5 years, whose developmental status was assessed during their first year of full-time school enrollment. Individual-level information was probabilistically linked across three administrative datasets. Logistic regression models were used to estimate the association (odds ratio (OR)) between early life characteristics of children and teacher-rated vulnerability on one or more of five domains of development. The crude OR for developmental vulnerability was much greater for Aboriginal than non-Aboriginal children (OR: 6.93, 95% CI: 5.62–8.56). After adjustment for other variables, the increased risk of developmental vulnerability for Aboriginal children was substantially moderated (OR: 1.68, 95% CI: 1.21–2.32). Influential factors in the adjusted model included: English as a second language (OR: 3.11, 95% CI: 2.27–4.26), gestational age at birth of 34–36 weeks (OR: 2.08, 95% CI: 1.27–3.39) and living in a very remote area (OR: 1.68, 95% CI: 1.19–2.37). There was a gradient in the strength of the association with the level of primary caregiver’s education. An additional risk, for Aboriginal children only, was not having attended a day care or pre-school program (OR: 1.43, 95% CI: 1.01–2.04). The study demonstrates the emerging capacity for linkage of data across administrative datasets to inform our understanding of the extent to which multiple factors in early-life operate in their association with children’s early development. Our findings are of particular relevance to initiatives to improve outcomes for Aboriginal children by demonstrating that potentially modifiable health and socio-economic factors account for almost all of the difference in developmental vulnerabilities observed between Aboriginal and non-Aboriginal children. [ABSTRACT FROM AUTHOR]

Background: Accumulation of hyperphosphorylated tau is a major neuropathological feature of tauopathies including Alzheimer's disease (AD). Serum amyloid A (SAA), an acute-phase protein with cytokine-like property, has been implicated in amyloid deposition. It remains unclear whether SAA affects tau hyperphosphorylation.Methods: Potential involvement of SAA in tau hyperphosphorylation was examined using intracerebral injection of SAA, and in Saa3 (-/-) mice receiving systemic administration of lipopolysaccharide (LPS). Induced SAA expression and microglial activation were evaluated in these mice using real-time PCR and/or immunofluorescence staining. Cultured primary neuronal cells were treated with condition media (CM) from SAA-stimulated primary microglial cells. The alteration in tau hyperphosphorylation was determined using Western blotting.Results: Saa3 is the predominant form of SAA proteins induced by LPS in the mouse brain that co-localizes with neurons. Overexpression of SAA by intracerebral injection attenuated tau hyperphosphorylation in the brain. Conversely, Saa3 deficiency enhanced tau phosphorylation induced by systemic LPS administration. Intracerebral injection of SAA also induced the activation of microglia in the brains. IL-10 released to CM from SAA-stimulated microglia attenuated tau hyperphosphorylation in cultured primary neurons. IL-10 neutralizing antibody reversed the effect of SAA in the attenuation of tau phosphorylation.Conclusions: LPS-induced expression of SAA proteins in the brain leads to the activation of microglia and release of IL-10, which in turn suppresses tau hyperphosphorylation in a mouse model of systemic inflammation. [ABSTRACT FROM AUTHOR]

Background: Pathological features of Alzheimer's disease (AD) include aggregation of amyloid beta (Aβ) and tau protein. Macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, has been implicated in the toxicity of aggregated Aβ. It remains unclear whether MIF affects hyperphosphorylation and aggregation of tau.Methods: The effects of MIF deficiency in tau hyperphosphorylation were examined in Mif (-/-) mice receiving intracerebroventricular (ICV) injection of streptozotocin (STZ) and in APP/PS1 transgenic mice mated with Mif (-/-) mice. MIF expression and astrocyte activation were evaluated in ICV-STZ mice using immunofluorescence staining. Cultured primary astrocytes were treated with high glucose to mimic STZ function in vitro, and the condition medium (CM) was collected. The level of tau hyperphosphorylation in neurons treated with the astrocyte CM was determined using Western blotting.Results: MIF deficiency attenuated tau hyperphosphorylation in mice. ICV injection of STZ increased astrocyte activation and MIF expression in the hippocampus. MIF deficiency attenuated astrocyte activation in ICV-STZ mice. CM from high glucose-treated WT astrocytes increased tau hyperphosphorylation in cultured primary neurons, an effect absent from Mif (-/-) astrocytes and WT astrocytes treated with the MIF inhibitor ISO-1. ISO-1 had no direct effect on tau phosphorylation in cultured primary neurons.Conclusions: These results suggest that MIF deficiency is associated with reduced astrocyte activation and tau hyperphosphorylation in the mouse AD models tested. Inhibition of MIF and MIF-induced astrocyte activation may be useful in AD prevention and therapy. [ABSTRACT FROM AUTHOR]

Aim This study investigated the association between early-life risk factors and school education outcomes. Methods This is an historical cohort study of 7601 children (61% were Indigenous) born in the Northern Territory between 1999 and 2004. Information was linked, for each child on: perinatal health, student enrolment and National Assessment Program - Literacy and Numeracy ( NAPLAN) Year 3 results. Logistic regression was used to estimate the association between selected risk factors and a NAPLAN result 'below' the national minimum standard ( NMS) in reading and numeracy. Results Indigenous children had much higher odds, than non- Indigenous children, of a result below the NMS for both reading (odds ratio ( OR): 8.58, 95% confidence interval ( CI): 7.55-9.74) ) and numeracy ( OR: 11.52, 95% CI: 9.94-13.35). When adjusted for all other variables, the increased odds were attenuated for both reading ( OR: 2.89, 95% CI: 2.46-3.40) and numeracy ( OR: 3.19, 95% CI: 2.65-3.84). Common risk factors for Indigenous and non- Indigenous children included higher birth order, maternal smoking in pregnancy and being a boy. There were gradients of decreasing risk with increasing education level of primary care giver and increasing maternal age. Among Indigenous children only, risks increased when living in remote areas, with younger age (<8 years) and low birthweight. Conclusions The study highlights that many of the risk factors associated with poor education outcomes among Indigenous children are shared with the general population. The results inform a targeted, cross-agency response to address modifiable early-life risk factors for educational disadvantage. Data linkage, using existing administrative datasets, provides a useful addition to methods that identify priority areas for prevention and early intervention. [ABSTRACT FROM AUTHOR]

Abstract: A nanocomposite was fabricated using poly(vinylidene fluoride) (PVDF) as matrix and poly(p-chloromethyl styrene) (PCMS) grafted with high dielectric constant copper phthalocyanine oligomer (CuPc) (PCMS-g-CuPc) as filler. Transmission electron microscopic morphologies reveal that the PCMS-g-CuPc particle size of ca. 80nm in average are dispersed in PVDF matrix, while in PCMS-g-CuPc particles the PCMS acts as “matrix” which contains dispersed CuPc balls with a average size of ca. 25nm [1/20 of that of CuPc in simple blend of PVDF and CuPc (PVDF/CuPc)]. The nanocomposite with only 15wt% CuPc can realize a dielectric constant of 325 at 100Hz, about 7 times larger than that of PVDF/CuPc, and nearly 40-fold enhancement with respect to that of the pure PVDF. The significant enhancement of dielectric response can be attributed to the remarkably strengthened exchange coupling effect as well as the Maxwell–Wagner–Sillars polarization mechanism. [Copyright &y& Elsevier]

Abstract: It has been reported that limb ischemic preconditioning (LIP) could induce brain ischemic tolerance. In the present study, we investigated the role of p38 MAPK in the induction of brain ischemic tolerance by observing expression of phosphorylated p38 (p-p38) MAPK in the hippocampus after LIP and the effect of p38 MAPK inhibitor SB 203580 on the protection of LIP against delayed neuronal death (DND) in the CA1 hippocampus induced normally by brain ischemic insult. The results of Flow cytometry and Western blotting showed that expression of p-p38 MAPK initially increased at 6 h after LIP compared with sham group in the CA1 hippocampus. The increases reached peak at 12 h and lasted to 24 h after LIP. Expression of p-p38 MAPK was also increased in the CA3/dentate gyrus (DG) regions after LIP, but the beginning and peaking times were 1 and 3 days after LIP, which were relatively later than those in the CA1. Histological evaluation showed that LIP protected the CA1 hippocampal pyramidal neurons against DND induced by global brain ischemic insult for 8 min, suggesting the occurrence of brain ischemic tolerance. Pretreatment with SB 203580 at 30 min before LIP effectively blocked the ischemic tolerance induced by LIP. Together, it could be concluded that activation of p38 MAPK played an important role in the brain ischemic tolerance induced by LIP, and that components of the p38 MAPK cascade might be targets to modify neuronal survival in ischemic tolerance. [Copyright &y& Elsevier]