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Human influenza A viruses (IAVs) cause global pandemics and epidemics, which remains a nonignorable serious concern for public health worldwide. To combat the surge of viral outbreaks, new treatments are urgently needed. Here, we design a new vaccine based on virus-like particles (VLPs) and show how intranasal administration of this vaccine triggers protective immunity, which can be exploited for the development of new therapies. H1N1 VLPs were produced in baculovirus vectors and were injected into BALB/c mice by the intramuscular (IM) or intranasal (IN) route. We found that there were significantly higher inflammatory cell and lymphocyte concentrations in bronchoalveolar lavage samples and the lungs of IN immunized mice; however, the IM group had little signs of inflammatory responses. On the basis of our results, immunization with H1N1 influenza VLP elicited a strong T cell immunity in BALB/c mice. Despite T cell immunity amplification after both IN and IM vaccination methods in mice, IN-induced T cell responses were significantly more intense than IM-induced responses, and this was likely related to an increased number of both CD11bhigh and CD103+ dendritic cells in mice lungs after IN administration of VLP. Furthermore, evaluation of interleukin-4 and interferon gamma cytokines along with several chemokine receptors showed that VLP vaccination via IN and IM routes leads to a greater CD4+ Th1 and Th2 response, respectively. Our findings indicated that VLPs represent a potential strategy for the development of an effective influenza vaccine; however, employing relevant routes for vaccination can be another important part of the universal influenza vaccine puzzle.  相似文献   
13.
Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a non-invasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory substitution.In this study,22 healthy participants took part besides 5 amputee participants.The duration time of the study was 31 days with five test steps according to the Leitner technique.An adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to participants.Also,to isolate the surround-ings and show colors,a Virtual Reality(VR)glass was employed.The statistical results conducted are based on the response of participants with questionnaire method.Using Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the"Repeated Measures ANOVA",it is noticed that the time of numbness felt by participants had significant(P value<0.001)difference.Participants could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object's temperature with only once time experimenting the color temperature.  相似文献   
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In this paper, a graphene-based tunable multi-band terahertz absorber is proposed and numerically investigated. The proposed absorber can achieve perfect absorption within both sharp and ultra-broadband absorption spectra. This wide range of absorption is gathered through a unique combination of periodically cross- and square-shaped dielectrics sandwiched between two graphene sheets; the latter enables it to offer more absorption in comparison with the traditional single-layer graphene structures. The aforementioned top layer is mounted on a gold plate separated by a Topas layer with zero volume loss. Furthermore, in our proposed approach, we investigated the possibility of changing the shapes and sizes of the dielectric layers instead of the geometry of the graphene layers to alleviate the edge effects and manufacturing complications. In numerical simulations, parameters, such as graphene Fermi energy and the dimensions of the proposed dielectric layout, have been optimally tuned to reach perfect absorption. We have verified that the performance of our dielectric layout called fishnet, with two widely investigated dielectric layouts in the literature (namely, cross-shaped and frame-and-square). Our results demonstrate two absorption bands with near-unity absorbance at frequencies of 1.6–2.3 and 4.2–4.9 THz, with absorption efficiency of 98% in 1.96 and 4.62 THz, respectively. Moreover, a broadband absorption in the 7.77–9.78 THz is observed with an absorption efficiency of 99.6% that was attained in 8.44–9.11 THz. Finally, the versatility provided by the tunability of three operation bands of the absorber makes it a great candidate for integration into terahertz optoelectronic devices.

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15.
Several studies have addressed the question of the time it takes for attention to shift from one position in space to another. Here we present a behavioural paradigm which offers a direct access to an estimate of voluntary shift time by comparing, in the same task, a situation in which subjects are required to re-engage their attention at the same spatial location with a situation in which they need to shift their attention to another location, all other sensory, cognitive and motor parameters being equal. We show that spatial attention takes on average 55 ms to voluntarily shift from one hemifield to the other and 38 ms to shift within the same hemifield. In addition, we show that across and within hemifields attentional processes are different. In particular, attentional spotlight division appears to be more difficult to operate within than across hemifields.  相似文献   
16.
Polysaccharide-protein gums are complex polymers with many applications in emulsion and emulsion-based products. It is crucial to enclose a concept on understanding of functional properties of polysaccharide-protein biopolymer in order to select the appropriate one based on the application scope. The main objective of the current study was to investigate the effect of three extraction variables on the surface activity, particle uniformity, apparent viscosity, and protein content of a natural polysaccharide-protein biopolymer from durian fruit seed. Three extraction variables namely water: seed (W/S) ratio (20:1?C60:1), temperature (25.0?C85.0?°C) and pH (4.0?C10.0) were considered as independent variables. The results indicated that durian seed gum induced very low viscosity (0.93?C4.98?mPa.s) with pseudoplastic rheological behavior in the aqueous system. The current study revealed that the extraction variables had the most significant (p?<?0.05) effect on the emulsifying surface activity of the natural biopolymer from durian fruit seed. This might be due to the significant (p?<?0.05) effect of the proteineous constituent present in the chemical structure of the biopolymer from durian fruit seed. The aqueous extraction variables showed the most and least significant (p?<?0.05) effect on the specific surface area and protein content, respectively. Among all extraction variables, W/S ratio and pH exhibited the highest and lowest significant (p?<?0.05) effect on the physicochemical and functional properties of the natural biopolymer from durian fruit seed.  相似文献   
17.
Development of an accurate protein–DNA recognition code that can predict DNA specificity from protein sequence is a central problem in biology. C2H2 zinc fingers constitute by far the largest family of DNA binding domains and their binding specificity has been studied intensively. However, despite decades of research, accurate prediction of DNA specificity remains elusive. A major obstacle is thought to be the inability of current methods to account for the influence of neighbouring domains. Here we show that this problem can be addressed using a structural approach: we build structural models for all C2H2-ZF–DNA complexes with known binding motifs and find six distinct binding modes. Each mode changes the orientation of specificity residues with respect to the DNA, thereby modulating base preference. Most importantly, the structural analysis shows that residues at the domain interface strongly and predictably influence the binding mode, and hence specificity. Accounting for predicted binding mode significantly improves prediction accuracy of predicted motifs. This new insight into the fundamental behaviour of C2H2-ZFs has implications for both improving the prediction of natural zinc finger-binding sites, and for prioritizing further experiments to complete the code. It also provides a new design feature for zinc finger engineering.  相似文献   
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2-Naphthylsulfonylhydrazine was reacted with aromatic aldehydes or aldehydo sugars to give the corresponding hydrazones which undergo Michael addition reactions with malononitrile or ethyl cyanoacetate to form pyrazole derivatives.  相似文献   
20.
Although primary and memory responses against bacteria and viruses have been studied extensively, T helper type 2 (T(H)2) effector mechanisms leading to host protection against helminthic parasites remain elusive. Examination of the intestinal epithelial submucosa of mice after primary and secondary infections by a natural gastrointestinal parasite revealed a distinct immune-cell infiltrate after challenge, featuring interleukin-4-expressing memory CD4(+) T cells that induced IL-4 receptor(hi) (IL-4R(hi)) CD206(+) alternatively activated macrophages. In turn, these alternatively activated macrophages (AAMacs) functioned as important effector cells of the protective memory response contributing to parasite elimination, demonstrating a previously unknown mechanism for host protection against intestinal helminths.  相似文献   
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