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We analyze the performance of a piezoelectric bimorph in the flexural mode for scavenging ambient vibration energy and evaluate the dependence of the performance upon the physical and geometrical parameters of the model bimorph. The analytical solution for the flexural motion of the piezoelectric bimorph shows that the output power density increases initially, reaches a maximum, and then decreases monotonically with increasing load impedance, which is normalized by a parameter that is a simple combination of the physical and geometrical parameters of the scavenging structure, the bimorph, and the frequency of the ambient vibration, underscoring the importance for the load circuit to have the impedance desirable by the scavenging structure. The numerical results illustrate the considerably enhanced performances achieved by adjusting the physical and geometrical parameters of the scavenging structure.

Corticotrophin-releasing factor (CRF) plays a pivotal role in stress-induced suppression of the gonadotrophin-releasing hormone pulse generator. We have previously shown that type 2 CRF receptors (CRF(2)) mediate restraint stress-induced suppression of luteinising hormone (LH) pulses in the rat. The present study aimed: (i) to determine whether type 1 CRF receptors (CRF(1)) are also involved in this response to restraint and (ii) to investigate the differential involvement of CRF(1) and CRF(2) in the suppression of LH pulses in response to the metabolic perturbation of insulin-induced hypoglycemia and the innate immunological challenge of lipopolysaccharide (LPS). Ovariectomised rats with oestrogen replacement were implanted with intracerebroventricular (i.c.v.) and intravenous (i.v.) cannulae. Blood samples (25 microl) were collected every 5 min for 5 h for LH measurement. After 2 h of controlled blood sampling, rats were either exposed to restraint (1 h) or injected intravenously with insulin (0.25 IU/kg) or LPS (5 microg/kg). All three stressors suppressed LH pulses. The CRF(1) antagonist SSR125543Q (11.5 micromol/rat i.v., 30 min before stressor) blocked the inhibitory response to restraint, but not hypoglycaemia or LPS stress. In addition to its effect on restraint, the CRF(2) antagonist astressin(2)-B (28 nmol/rat i.c.v., 10 min before insulin or LPS) blocked hypoglycaemia or LPS stress-induced suppression of LH pulses. These results suggest that hypoglycaemia and LPS stress-induced LH suppression involves activation of CRF(2) while restraint stress-induced inhibition of LH pulses involves both CRF(1) and CRF(2).

Azithromycin (AZM) is a widely used antibiotic, with additional antiviral and anti-inflammatory properties that remain poorly understood. Although Zika virus (ZIKV) poses a significant threat to global health, there are currently no vaccines or effective therapeutics against it. Here, we report that AZM effectively suppresses ZIKV infection in vitro by targeting a late stage in the viral life cycle. In addition, AZM upregulates the expression of host type I and III interferons and several of their downstream interferon-stimulated genes in response to ZIKV infection. In particular, we found that AZM upregulated the expression of MDA5 and RIG-I (pathogen recognition receptors induced by ZIKV infection) and increased the levels of phosphorylated TBK1 and IRF3. Interestingly, AZM treatment upregulated the phosphorylation of TBK1 without inducing the phosphorylation of IRF3 by itself. These findings highlight the potential use of AZM as a broad antiviral agent to combat viral infection and to prevent devastating ZIKV-associated clinical outcomes, such as congenital microcephaly.

Designing novel hybrid materials provides a means of controlling electrical, magnetic, or optical properties. [1][2][3][4][5][6][7][8] There have been numerous studies on preparing nanocomposite materials. One approach is synthesizing inorganic nanoparticles within the microdomain of a well-ordered block-copolymer template. [9][10][11][12] In a second approach the self-assembled microdomain morphology of block copolymers is used to control the spatial arrangement of nanoscopic elements within the materials. [4,[13][14][15][16] The manipulation of the location of the nanoparticles in the materials can be achieved by controlling the sizes and the surface properties of the nanoparticles. Recent theoretical arguments suggest that synergistic interactions between self-organizing particles and a self-assembling matrix material may lead to hierarchically ordered structures. [17][18][19] These predictions were recently confirmed in a study of a diblock copolymer having cylindrical microdomains with added nanoparticles. In this study a co-operative coupled interaction was found that led to hierarchically ordered structures upon thermal-or solvent-annealing where self-orienting, self-assembling arrays of microdomains were found without the use of external fields.[20] However, the details of the structural evolution, and the means of manipulating the synergistic interactions, were not described, and this is key for generalizing these concepts to different systems. In a recent study, to capture the detailed structural evolution of the self-assembly process in thin films of nanoparticles/copolymer-mixtures, in situ grazing-incident small-angle X-ray scattering (GISAXS) was used. In situ GISAXS has unique advantages: the sample is intact; the structure can be probed quickly at exactly the same place at different annealing times; and, in addition, the X-ray beam passes through quite a large area of the sample, which provides average information about the structure inside the sample. Here, we report on the structural evolution in thin films of a polystyrene-block-poly(2-vinylpyridine) copolymer, denoted as PS-b-P2VP, mixed with tri-n-octylphosphine oxide (TOPO)-covered CdSe nanoparticles. Even with the strong interfacial interactions of P2VP with the substrate, the addition of the nanoparticles to the strongly microphase-separated copolymer is seen to modify interfacial interactions and cause the microdomains to orient normal to the surface. In conjunction with our previous studies, a generality of these synergistic interactions is suggested.CdSe nanoparticles functionalized with TOPO ligands were prepared using established high-temperature procedures.[23] A series of experiments with different concentrations of the nanoparticles in the polymer has been tested. The condition of the effective low concentration of nanoparticles has been chosen in order to reveal the scattering from the block-polymer matrix. Solutions containing ca. 3 wt % PS-b-P2VP (54.9 K-18.6 K, cylindrical morphology, polydispersity index (PDI) = 1.06, Polymer ...

The posterodorsal medial amygdala (MePD) is a neural site in the limbic brain involved in regulating emotional and sexual behaviours. There is, however, limited information available on the specific neuronal cell type in the MePD functionally mediating these behaviours in rodents. The recent discovery of a significant kisspeptin neurone population in the MePD has raised interest in the possible role of kisspeptin and its cognate receptor in sexual behaviour. The present study therefore tested the hypothesis that the MePD kisspeptin neurone population is involved in regulating attraction towards opposite sex conspecifics, sexual behaviour, social interaction and the anxiety response by selectively stimulating these neurones using the novel pharmacosynthetic DREADDs (designer receptors exclusively activated by designer drugs) technique. Adult male Kiss‐Cre mice received bilateral stereotaxic injections of a stimulatory DREADD viral construct (AAV‐hSyn‐DIO‐hM3D(Gq)‐mCherry) targeted to the MePD, with subsequent activation by i.p. injection of clozapine‐N‐oxide (CNO). Socio‐sexual behaviours were assessed in a counter‐balanced fashion after i.p. injection of either saline or CNO (5 mg kg‐1). Selective activation of MePD kisspeptin neurones by CNO significantly increased the time spent by male mice in investigating an oestrous female, as well as the duration of social interaction. Additionally, after CNO injection, the mice appeared less anxious, as indicated by a longer exploratory time in the open arms of the elevated plus maze. However, levels of copulatory behaviour were comparable between CNO and saline‐treated controls. These data indicate that DREADD‐induced activation of MePD kisspeptin neurones enhances both sexual partner preference in males and social interaction and also decreases anxiety, suggesting a key role played by MePD kisspeptin in sexual motivation and social behaviour.

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