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This study systematically investigated the effect of equal channel angular pressing (ECAP) on the microstructure, mechanical, corrosion, nano-tribological properties and biocompatibility of a newly developed β Ti-28Nb-35.4Zr (hereafter denoted TNZ) alloy. Results indicated that ECAP of the β TNZ alloy refined its microstructure by forming ultrafine grains without causing stress-induced phase transformation, leading to formation of a single β phase. The ECAP-processed TNZ alloy exhibited a compressive yield strength of 960 MPa, and high plastic deformation capacity without fracturing under compression loads. Potentiodynamic polarization tests revealed the higher tendency of ECAP-processed TNZ alloys to form passive oxide films on its surface, which exhibited a lower corrosion rate (0.44±0.07 µm/y) in Hanks' balanced salt solution compared to its as-cast counterpart (0.71±0.10 µm/y). Nanotribological testing also revealed higher resistance of the ECAP-processed TNZ alloy to abrasion, wear and scratching, when compared to its as-cast counterpart. Cytocompatibility and cell adhesion assessments of the ECAP-processed TNZ alloys showed a high viability (111%) of human osteoblast-like SaOS2 cells after 7 d of culturing. Moreover, the ECAP-processed TNZ alloy promoted adhesion and spreading of SaOS2 cells, which exhibited growth and proliferation on alloy surfaces. In summary, significantly enhanced mechanical, corrosion, and biological properties of ECAP-processed TNZ alloy advocate its suitability for load-bearing implant applications. Equal channel angular pressing (ECAP) provides a unique combination of enhanced mechanical and functional properties of materials by optimizing their microstructures and phase transformations. This study investigated the mechanical, nano-tribological, corrosion, and biocompatibility properties of a newly developed β Ti-28Nb-35.4Zr (TNZ) alloy processed via ECAP. Our findings indicated that ECAP of the β TNZ alloy refined its microstructure by forming ultrafine grains without causing stress-induced phase transformation. Compared to its as-cast counterpart, ECAP-processed TNZ exhibited significantly enhanced compressive yield strength, plastic deformation capacity, hardness, wear, and corrosion properties. Moreover, in vitro cytocompatibility and cell adhesion studies revealed high cellular viabilities, growth and proliferation of osteoblast-like SaOS2 cells on the ECAP-processed TNZ alloy. [Display omitted] [ABSTRACT FROM AUTHOR]

This report documents the characterization of a novel mouse oocyte protein which was originally identified by microsequence analysis of a 67.8 kDa protein spot (pI 5.7) on a Coomassie-stained two-dimensional (2D) gel of murine egg proteins. Tandem mass spectroscopic analysis of the peptides obtained from the cored protein yielded sequences that appeared to match only ovary, egg, and preimplantation embryo cDNAs. We then cloned the novel gene by RACE-PCR, and analysis of the deduced eDNA sequence found that this maternal product was ~56% identical to human cytosolic phospholipase A2[gamma] (cPLA2[gamma]). Based on this sequence homology, we named the molecule mouse cytosolic phospholipase A2[gamma] (cPLA2[gamma]). As with human cPLA2[gamma], mouse cPLA2[gamma] contains a lipase consensus sequence and lacks the calcium binding domain that is found in other PLA2 proteins. However, mouse cPLA2[gamma] is different from human cPLA2[gamma] in that mouse cPLA2[gamma] expression is restricted to the ovary and that the protein does not contain the myristoylation and prenylation lipid-anchoring motifs that are present in human cPLA2[gamma]. Within oocytes, mouse cPLA2[gamma] localizes mainly to the oocyte cortex and to the nucleoplasm. Interestingly, during germinal vesicle breakdown, mouse cPLA2[gamma] aggregates dynamically relocate from the oocyte cortex to the nuclear envelope, suggesting a possible role for this putative egg-restricted phospholipase A2[gamma] in membrane remodeling. Furthermore, mouse cPLA2[gamma] protein continues to be expressed in the embryo until the 4-8-cell stage of development, suggesting that mouse cPLA2[gamma] may function as a previously uncharacterized maternal effect gene. Keywords: cPLA2[gamma]; Maturation; Fertilization; Preimplantation

Selected for its high relative abundance, a protein spot of MW ~75 kDa, pI 5.5 was cored from a Coomassie-stained two-dimensional gel of proteins from 2850 zona-free metaphase II mouse eggs and analyzed by tandem mass spectrometry (TMS), and novel microsequences were identified that indicated a previously uncharacterized egg protein. A 2.4-kb cDNA was then amplified from a mouse ovarian adapter-ligated cDNA library by RACE-PCR, and a unique 2043-bp open reading frame was defined encoding a 681-amino-acid protein. Comparison of the deduced amino acid sequence with the nonredundant database demonstrated that the protein was ~40% identical to the calcium-dependent peptidylarginine deiminase (PAD) enzyme family. Northern blotting, RT-PCR, and in situ hybridization analyses indicated that the protein was abundantly expressed in the ovary, weakly expressed in the testis, and absent from other tissues. Based on the homology with PADs and its oocyte-abundant expression pattern, the protein was designated ePAD, for egg and embryo-abundant peptidylarginine deiminase-like protein. Anti-recombinant ePAD monospecific antibodies localized the molecule to the cytoplasm of oocytes in primordial, primary, secondary, and Graafian follicles in ovarian sections, while no other ovarian cell type was stained, ePAD was also expressed in the immature oocyte, mature egg, and through the blastocyst stage of embryonic development, where expression levels began to decrease. Immunoelectron microscopy localized ePAD to egg cytoplasmic sheets, a unique keratin-containing intermediate filament structure found only in mammalian eggs and in early embryos, and known to undergo reorganization at critical stages of development. Previous reports that PAD-mediated deimination of epithelial cell keratin results in cytoskeletal remodeling suggest a possible role for ePAD in cytoskeletal reorganization in the egg and early embryo.

Allergic asthmatic subjects are uniquely susceptible to acute wheezing episodes provoked by rhinovirus. However, the underlying immune mechanisms and interaction between rhinovirus and allergy remain enigmatic, and current paradigms are controversial. We sought to perform a comprehensive analysis of type 1 and type 2 innate and adaptive responses in allergic asthmatic subjects infected with rhinovirus. Circulating virus-specific T H 1 cells and allergen-specific T H 2 cells were precisely monitored before and after rhinovirus challenge in allergic asthmatic subjects (total IgE, 133-4692 IU/mL; n = 28) and healthy nonallergic controls (n = 12) using peptide/MHCII tetramers. T cells were sampled for up to 11 weeks to capture steady-state and postinfection phases. T-cell responses were analyzed in parallel with 18 cytokines in the nose, upper and lower airway symptoms, and lung function. The influence of in vivo IgE blockade was also examined. In uninfected asthmatic subjects, higher numbers of circulating virus-specific PD-1+ T H 1 cells, but not allergen-specific T H 2 cells, were linked to worse lung function. Rhinovirus infection induced an amplified antiviral T H 1 response in asthmatic subjects versus controls, with synchronized allergen-specific T H 2 expansion, and production of type 1 and 2 cytokines in the nose. In contrast, T H 2 responses were absent in infected asthmatic subjects who had normal lung function, and in those receiving anti-IgE. Across all subjects, early induction of a minimal set of nasal cytokines that discriminated high responders (G-CSF, IFN-γ, TNF-α) correlated with both egress of circulating virus-specific T H 1 cells and worse symptoms. Rhinovirus induces robust T H 1 responses in allergic asthmatic subjects that may promote disease, even after the infection resolves. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) and its alloys are considered promising biodegradable implant materials because of their strength and natural degradation in the human body. However, the high corrosion rate of pure Mg in the physiological environment leads to rapid degradation before adequate bone healing. This mismatch between bone healing and the degradation of Mg implants supports the development of new Mg alloys with the addition of other suitable alloying elements in order to achieve simultaneously high corrosion resistance and desirable mechanical properties. This study systematically investigates the microstructure, mechanical properties, corrosion behavior, and biocompatibility of Mg-based alloys with the addition of different concentrations of scandium (Sc), i.e., Mg-0.6Zr-0.5Sr-xSc (x = 0.5, 1, 2, 3 wt.%). Results indicated that high concentration of Sc in strontium (Sr)-containing Mg alloys can alter their microstructures by suppressing the intermetallic phases along the grain boundaries and improve the corrosion resistance by forming chemically stable Sc oxide layers on the surfaces of the Mg alloys. Cytotoxicity assessment revealed that the Sc containing Mg alloys did not significantly alter the viability of human osteoblast-like SaOS2 cells. This study highlights the advantages of using Sc as an alloying element to simultaneously tune Mg alloys with higher strength and slower degradation. Rare earth elements such as scandium (Sc) with both a high solid-solubility and strong affinity towards oxygen can improve the mechanical and corrosion properties of magnesium (Mg) alloys. However, the feasibility of Sc-containing Mg alloys as biodegradable implant materials is scarcely reported. This study investigates the effects of different Sc concentrations on the mechanical, corrosion, and biocompatibility properties of Mg-Zr-Sr-Sc alloys. Our findings indicated that the addition of Sc significantly improves the mechanical and corrosion properties of Mg-Zr-Sr alloys. Moreover, in vitro cytotoxicity assessment of the Mg-Zr-Sr-Sc alloys did not show any adverse effects on the viability of osteoblast-like cells. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract Viewing sexually explicit materials (SEM) has become a normal sexual experience for many adolescents, and there are those who perceive that SEM has impacted them in a positive manner. There are growing concerns among parents, educators, and medical professionals over adolescents' use of SEM, however, which include fears that SEM distorts young people's views and understanding of human sexuality. Given the gap in the assessment of associations between SEM use and perceived SEM reality across time, this study used a panel sample of 875 Croatian 16-year-olds (67.3% of female gender) to estimate parallel latent growth in SEM use and SEM realism over a 23-month period. We observed a significant increase in SEM use and a significant (non-linear) decrease in SEM realism in both genders, but no statistically significant correspondence between the two constructs. It has been assumed that adolescents will dismiss SEM as unrealistic once they become sexually experienced. This hypothesis received only limited support, suggesting the role of other, unmeasured, moderators, but also the importance of expanding the currently limited conceptualization and measurement of SEM realism. Highlights • Longitudinal panel data gathered from Croatian adolescents over 23-month period. • Sexually explicit media (SEM) use and realism perceptions assessed. • SEM use increased while perceptions of SEM realism decreased, albeit non-linearly. • Changes in SEM use were uncorrelated with changes in SEM realism perceptions. • Sexual experience was related to SEM realism perceptions at baseline only. [ABSTRACT FROM AUTHOR]

Abstract Using national probability data gathered between 1990 and 2016, this study explored associations between pornography consumption and sexual permissiveness within and between the sexes, as well as permissiveness differences between the sexes across categories of pornography use. Its goal was to compare whether theory from the social learning or evolutionary psychology paradigms could better explain the results. In support of social learning: pornography consumption was associated with higher permissiveness within sex; associations between pornography use and permissive sexual attitudes were generally stronger for men than women; and attitudinal sex differences among nonconsumers became smaller over time. In support of evolutionary psychology: women were never more permissive than men; men were often more permissive than women, especially behaviorally; and the largest and most consistent sex differences were for paid sex behavior. That a combination of social learning and evolutionary perspectives explains the results better than either perspective standing alone is discussed. [ABSTRACT FROM AUTHOR]

Abstract This report presents data on pornography consumption, perceptions of pornography, and condom use among a sample of 140 women in South Korea. Three key findings emerged. First, perceiving pornography as a source of sexual information was a more reliable correlate of less consistent condom use than the frequency with which pornography was viewed. Second, consuming pornography more frequently only predicted using condoms less frequently when pornography was perceived as a source of sexual information. Third, the interaction between the rate of pornography consumption and perceiving pornography as a source of sexual information maintained even after adjusting for pertinent demographic characteristics. Taken together, these findings suggest that while perceiving pornography as a source of sexual information in and of itself is a risk-factor for engaging in unprotected sex, the combination of regular pornography consumption and perceiving pornography as a source of sexual information is more problematic in terms of sexual risk than either variable in isolation. Sampling specifics and methodological singularity, however, point to a need for replication studies from other locales and using additional designs. [ABSTRACT FROM AUTHOR]

Previous studies of the murine Ly49 and human KIR gene clusters implicated competing sense and antisense promoters in the control of variegated gene expression. In the current study, an examination of transcription factor genes defines an abundance of convergent and divergent sense/antisense promoter pairs, suggesting that competing promoters may control cell fate determination. Differentiation of CD34+ hematopoietic progenitors in vitro shows that cells with GATA1 antisense transcription have enhanced GATA2 transcription and a mast cell phenotype, whereas cells with GATA2 antisense transcription have increased GATA1 transcripts and an erythroblast phenotype. Detailed analyses of the AHR and RORC genes demonstrate the ability of competing promoters to act as binary switches and the association of antisense transcription with an immature/progenitor cell phenotype. These data indicate that alternative cell fates generated by promoter competition in lineage-determining transcription factors contribute to the programming of cell differentiation. [Display omitted] • 18% of human transcription factors contain both divergent and convergent antisense • Cells transcribing GATA1 or GATA2 antisense are distinct from cells with coding transcripts • Stable sense or antisense transcriptional states exist in transcription factor genes • Antisense transcription is associated with progenitor cells Li and colleagues describe the presence of a regulatory motif containing both convergent and divergent antisense promoters in 18% of human transcription factors. They demonstrate the ability of competing promoters to act as switches and propose a role for these elements in the programming of cell fate. [ABSTRACT FROM AUTHOR]

Background and Objective: The transfer of acute ischemic stroke (AIS) patients to a comprehensive stroke center (CSC) must be rapid. Delays pose an obstacle to time-sensitive stroke treatments and, therefore, increase the likelihood of exclusion from endovascular stroke therapy. This study aims to evaluate the impact of the Stroke Rescue Program, with its goal of minimizing interfacility transfer delays and increasing the number of transport times completed within 60 minutes.Methods: The Stroke Rescue Program was initiated to facilitate the rapid transfer of AIS patients from regional primary stroke centers (PSCs) to the network's CSC. The transfer process was divided into 3 time elements: transport 1 time (initial phone call from the PSC until emergency medical service [EMS] arrival at the PSC), emergency department (ED) time (EMS PSC arrival to PSC departure), and transport 2 time (PSC departure to CSC arrival). The total transport time target was set at less than 60 minutes. Protocols and procedures were implemented with a focus on decreasing the ED time.Results: Comparing baseline (preimplementation) quarter (n = 21) to postproject quarter (1 year later, n = 31), the percent transported within 60 minutes increased from 62% to 81%. A statistically significant improvement was seen for both median ED time (23 minutes versus 14 minutes; U = 171, P < .01) and median total transport time (56 minutes versus 44 minutes; U = 199, P < .05).Conclusion: Interfacility transfer protocols minimizing the time paramedics spend in a PSC ED can significantly reduce total transfer time to a comprehensive stroke center. [ABSTRACT FROM AUTHOR]

The work presented here documents the characterization and testing of a novel, proximity-based AC current sensor. By using a pair of cross-coupled MEMS piezoelectric cantilevers that have oppositely-oriented magnets on their free ends, a sensor has been created that needs no external power source and that measures AC current without the need for galvanic contact with, or fully encircling of, the current-carrying conductor. The resulting device is 11.2 mm long and has an output sensitivity of 5.8 mV/G at 6.8 mm from the center of the conductor. The sensor device has been characterized at frequencies of 60⬜200 Hz. Common-mode rejection ratio calculations demonstrate the effectiveness of the cancellation technique at frequencies other than those corresponding to the first resonant mode of the device. [ABSTRACT FROM AUTHOR]

Flexibility, lightness and printability make organic solar cells (OSC) strong candidates to power low consumption devices such as envisioned for the Internet of Things. Such devices may be placed indoors, where light levels are well below typical outdoors level. Here, we demonstrate that maximizing the efficiency of OSC for indoor operation requires specific device optimization. In particular, minimizing the dark current of the solar cells is critical to enhance their efficiency under indoor light. Cells optimized for sunlight reach 6.2% power conversion efficiency (PCE). However when measured under simulated indoor light conditions, the PCE is to 5.2%. Cells optimized for indoor operation yield 7.6% of PCE under indoor conditions. As a proof-of-concept, the solar cells are combined with fully printed super-capacitors to form a photo-rechargeable system. Such a system with a 0.475 cm 2 indoor-optimized solar cell achieved a total energy conversion and storage efficiency (ECSE) of 1.57% under 1-sun, providing 26 mJ of energy and 4.1 mW of maximum power. Under simulated indoor light the system yielded an ECSE of 2.9%, while delivering 13.3 mJ and 2.8 mW. Those energy and power levels would be sufficient to power low-consumption electronic devices with low duty cycles. [ABSTRACT FROM AUTHOR]

Microplastics are known to be an increasing component found within both marine sediments and the water column. This study carried out an initial assessment of the levels of microplastics present within the Solent estuarine complex, focusing specifically on the water column. A plankton net trawl survey was carried out, with samples analysed using visual observation and Fourier Transform Infrared Spectroscopy (FT-IR). The study identified significant quantities of plastics, ranging in shape, with hot spots found at confluence points within the estuary. Though the FT-IR analysis was inconclusive, the nature of the samples indicates the effect of oceanographic conditions on the prevalent types of microplastics found, which in turn identifies key local sources such as wastewater treatment plants and the plastics industry as being the dominant inputs. [ABSTRACT FROM AUTHOR]

The anterior temporal lobe (ATL) plays a prominent role in models of semantic knowledge, although it remains unclear how the specific subregions within the ATL contribute to semantic memory. Patients with neurodegenerative diseases, like semantic dementia, have widespread damage to the ATL thus making inferences about the relationship between anatomy and cognition problematic. Here we take a detailed anatomical approach to ask which substructures within the ATL contribute to conceptual processing, with the prediction that the perirhinal cortex (PRc) will play a critical role for concepts that are more semantically confusable. We tested two patient groups, those with and without damage to the PRc, across two behavioural experiments – picture naming and word–picture matching. For both tasks, we manipulated the degree of semantic confusability of the concepts. By contrasting the performance of the two groups, along with healthy controls, we show that damage to the PRc results in worse performance in processing concepts with higher semantic confusability across both experiments. Further by correlating the degree of damage across anatomically defined regions of interest with performance, we find that PRc damage is related to performance for concepts with increased semantic confusability. Our results show that the PRc supports a necessary and crucial neurocognitve function that enables fine-grained conceptual processes to take place through the resolution of semantic confusability. [ABSTRACT FROM AUTHOR]

This study explores the nature of the relationship between informational social support and components of online health information seeking and how this process influences college students’ healthy eating intentions. Results showed that social support was positively associated with online information seeking and more favorable impressions of nutrition/healthy diet information on the web. In addition, although social support was not associated with healthy eating intentions, all three information-seeking measures significantly predicted this outcome – even after controlling for numerous health-related factors. Additional mediation tests showed that social support had an indirect impact on healthy eating intentions through use as well as through a multi-step process involving perceptions of online resources. Overall, these results suggest that by raising health consciousness, informational support may trigger online health information seeking leading to healthier lifestyle intentions. [ABSTRACT FROM AUTHOR]

Abstract: Inhibitory natural killer (NK) cell receptors specific for major histocompatibility complex class I (MHC-I) molecules include Ly49 receptors in mice and killer immunoglobulin-like receptors (KIR) in humans. The “licensing” or “arming” models imply that engagement of these receptors to self MHC-I molecules during NK cell development educates NK cells to be more responsive to cancer and viral infection. We recently reported that hematopoietic stem cell transplantation (HSCT) induced rapid and preferential expansion of functionally competent Ly49G+, but not other Ly49 family, NK cells independent of NK cell licensing via Ly49–MHC-I interactions. We now extend these studies to evaluate expression of the two Ly49G receptor isoforms Ly49GB6 and Ly49GBALB, using mice with different MHC-I haplotypes that express one or both of the isoforms. NK cells from CB6F1 (H-2bxd) hybrid mice express two different alleles for Ly49G receptor, Ly49GB6 and Ly49GBALB. We found that CB6F1 mice had more Ly49GB6+ NK cells than Ly49BALB+ NK cells, and that only Ly49GB6+ NK cells increased in relative numbers and in Ly49G mean fluorescence intensity values after HSCT similar to the B6 parental strain. We further observed that Ly49G+ NK cells in BALB/c (H-2d) and BALB.B (H-2b) mice, which have the same background genes, recover slowly after HSCT, in contrast to Ly49G+ NK cells in B6 (H-2b) recipients. The difference in expression of Ly49GB6 relative to Ly49GBALB was linked to differences in the activity of the Pro1 promoter between the two alleles. Thus, we conclude that the Ly49GB6 receptor dominates Ly49G expression on NK cells after HSCT in strains in which that allele is expressed. The data suggest that Ly49 allelic polymorphism within a particular Ly49 family member can differentially affect NK cell recovery after HSCT depending on the background genes of the recipient, not on the MHC-I haplotype. [Copyright &y& Elsevier]