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Chiral metamaterials represent a special type of artificial structures that cannot be superposed to their mirror images. Due to the lack of mirror symmetry, cross-coupling between electric and magnetic fields exist in chiral mediums and present unique electromagnetic characters of circular dichroism and optical activity, which provide a new opportunity to tune polarization and realize negative refractive index. Chiral metamaterials have attracted great attentions in recent years and have given rise to a series of applications in polarization manipulation, imaging, chemical and biological detection, and nonlinear optics. Here we review the fundamental theory of chiral media and analyze the construction principles of some typical chiral metamaterials. Then, the progress in extrinsic chiral metamaterials, absorbing chiral metamaterials, and reconfigurable chiral metamaterials are summarized. In the last section, future trends in chiral metamaterials and application in nonlinear optics are introduced.

Wireless sensor networks (WSNs) have been widely deployed in different application domains ranging between environment monitoring, transportation, target tracking, and health care. However, due to the limited power supply of the sensors, the researchers introduce mobile sinks in WSNs to prolong its lifetime. When introducing the mobile sinks in WSNs, the authentication issue between the mobile sink and the sensors appears. However, there are few studies on the authentication issue when using mobile sinks in WSNs. In this paper, we present a bilinear pairing based authentication and key agreement scheme for the authentication between mobile sinks and cluster head in WSNs. The proposed scheme can solve the problems of mobile sink authentication and provide data confidentiality and integrity. Security and performance analysis demonstrate that the proposed scheme can resist against various attacks and meet the requirements of computational complexity in the environment of WSNs.

Variations in elevation limit the growth and distribution of alpine plants because multiple environmental stresses impact plant growth, including sharp temperature shifts, strong ultraviolet radiation exposure, low oxygen content, etc. Alpine plants have developed special strategies to help survive the harsh environments of high mountains, but the internal mechanisms remain undefined. Kobresia pygmaea, the dominant species of alpine meadows, is widely distributed in the Southeastern Tibet Plateau, Tibet Autonomous Region, China. In this study, we mainly used comparative proteomics analyses to investigate the dynamic protein patterns for K. pygmaea located at four different elevations (4600, 4800, 4950 and 5100 m). A total of 58 differentially expressed proteins were successfully detected and functionally characterized. The proteins were divided into various functional categories, including material and energy metabolism, protein synthesis and degradation, redox process, defense response, photosynthesis, and protein kinase. Our study confirmed that increasing levels of antioxidant and heat shock proteins and the accumulation of primary metabolites, such as proline and abscisic acid, conferred K. pygmaea with tolerance to the alpine environment. In addition, the various methods K. pygmaea used to regulate material and energy metabolism played important roles in the development of tolerance to environmental stress. Our results also showed that the way in which K. pygmaea mediated stomatal characteristics and photosynthetic pigments constitutes an enhanced adaptation to alpine environmental stress. According to these findings, we concluded that K. pygmaea adapted to the high-elevation environment on the Tibetan Plateau by aggressively accumulating abiotic stress-related metabolites and proteins and by the various life events mediated by proteins. Based on the species'lexible physiological and biochemical processes, we surmised that environment change has only a slight impact on K. pygmaea except for possible impacts to populations on vulnerable edges of the species' range.

Plantlets of Populus yunnanensis Dode were examined in a greenhouse for 48 h to analyze their physiological and proteomic responses to sustained heat, drought, and combined heat and drought. Compared with the application of a single stress, simultaneous treatment with both stresses damaged the plantlets more heavily. The plantlets experienced two apparent response stages under sustained heat and drought. During the first stage, malondialdehyde and reactive oxygen species (ROS) contents were induced by heat, but many protective substances, including antioxidant enzymes, proline, abscisic acid (ABA), dehydrin, and small heat shock proteins (sHSPs), were also stimulated. The plants thus actively defended themselves against stress and exhibited few pathological morphological features, most likely because a new cellular homeostasis was established through the collaborative operation of physiological and proteomic responses. During the second stage, ROS homeostasis was overwhelmed by substantial ROS production and a sharp decline in antioxidant enzyme activities, while the synthesis of some protective elements, such as proline and ABA, was suppressed. As a result, photosynthetic levels in P. yunnanensis decreased sharply and buds began to die, despite continued accumulation of sHSPs and dehydrin. This study supplies important information about the effects of extreme abiotic environments on woody plants.

BACKGROUND: A wealth of evidence based on the randomized controlled trials (RCTs) has indicated that surgery may be a better choice in the management of primary intracerebral hemorrhage (ICH) compared to conservative treatment. However, there is considerable controversy over selecting appropriate surgical procedures for ICH. Thus, this meta-analysis was performed to assess the effects of stereotactic aspiration compared to craniotomy in patients with ICH. METHODS: According to the study strategy, we searched PUBMED, EMBASE and Cochrane Central Register of Controlled Trials. Other sources such as the internet-based clinical trial registries, relevant journals and the lists of references were also searched. After literature searching, two investigators independently performed literature screening, assessment of quality of the included trials and data extraction. The outcome measures included death or dependence, total risk of complication, and the risk of rebleeding, gastrointestinal hemorrhage and systematic infection. RESULTS: Four RCTs with 2996 participants were included. The quality of the included trials was acceptable. Stereotactic aspiration significantly decreased the odds of death or dependence at the final follow-up (odds ratio (OR): 0.80, 95% confidence interval (CI): 0.69-0.93; P = 0.004) and the risk of intracerebral rebleeding (OR: 0.44, 95% CI: 0.26-0.74; P = 0.002) compared to craniotomy with no significant heterogeneity among the study results. CONCLUSIONS: The present meta-analysis provides evidence that the stereotactic aspiration may be associated with a reduction in the odds of being dead or dependent in primary ICH, which should be interpreted with caution. Further trials are needed to identify those patients most likely to benefit from the stereotactic aspiration.

Radiotherapy is the standard treatment for cervical cancer, but causes radiotherapy-induced complications. Recently, chemotherapy has been more extensively utilized. Here, we perform a large-scale comparison of chemotherapy and radiotherapy. From 2002 to 2008, 2,268 patients were grouped according to adjuvant radiotherapy or chemotherapy before and/or after surgery, and we compared the 5-year overall survival (OS) and disease-free survival (DFS) rates, recurrence rates, side effects, quality of life (QoL), and sexual activity. There were no significant differences between the treatment groups for the 5-year OS and DFS rates (OS: p = 0.053, DFS: p = 0.095), although marginally improved outcomes were observed in the chemotherapy group (OS: 86.5% vs. 82.8%; DFS: 84.5% vs. 81.4%). However, patients with early-stage disease, clinical response, and younger age had increased 5-year OS and DFS rates following chemotherapy compared to radiotherapy (p

BACKGROUND: Follicular stimulating hormone (FSH) is a glycoprotein and widely used for the treatment of infertility; FSH action is mediated by FSH receptor (FSHR), SNPs of which determine the ovarian response. Two polymorphisms of the FSHR gene were identified, which caused a change of threonine (T) to alanine (A) at position 307 and asparagine (N) to serine(S) at position 680. Both polymorphic sites give rise to three discrete variants of the FSHR: TT, TA, and AA for position 307; NN, NS, and SS for position 680. METHODOLOGY/PRINCIPAL FINDINGS: 450 Chinese women were recruited in an assisted reproductive technology program from October 2011 to March 2012. FSHR polymorphisms at the positions 307 and 680 were examined by PCR-RFLP. Serum FSH and estradiol level, FSH amount, ovarian response and pregnancy rate were recorded during treatment. The basal FSH levels were higher in AA [7.38 ± 2.07 vs 6.34 ± 1.75, 6.63 ± 1.94, P

Stipa purpurea (S. purpurea) is the dominant plant species in the alpine steppe of the Qinghai-Tibet Plateau, China. It is highly resistant to cold and drought conditions. However, the underlying mechanisms regulating the stress tolerance are unknown. In this study, a CIPK gene from S. purpurea (SpCIPK26) was isolated. The SpCIPK26 coding region consisted of 1392 bp that encoded 464 amino acids. The protein has a highly conserved catalytic structure and regulatory domain. The expression of SpCIPK26 was induced by drought and salt stress. SpCIPK26 overexpression in Arabidopsis thaliana (A. thaliana) plants provided increased tolerance to drought and salt stress in an abscisic acid (ABA)-dependent manner. Compared with wild-type A. thaliana plants, SpCIPK26-overexpressing plants had higher survival rates, water potentials, and photosynthetic efficiency (Fv/Fm), as well as lower levels of reactive oxygen species (ROS) following exposure to drought and salt stress. Gene expression analyses indicated stress-inducible genes (RD29A, RD29B, and ABF2) and a ROS-scavenger gene (CAT1) were upregulated in SpCIPK26-overexpressing plants after stress treatments. All of these marker genes are associated with ABA-responsive cis-acting elements. Additionally, the similarities in the gene expression patterns following ABA, mannitol, and NaCl treatments suggest SpCIPK26 has an important role during plant responses to drought and salt stress and in regulating ABA signaling.

This paper presents a novel approach towards showing how contractor in agent-based simulation for complex warfare system such as multi-sensor battlefield reconnaissance system can be selected in Contract Net Protocol (CNP) with high efficiency. We first analyze agent and agent-based simulation framework, CNP and collaborators, and present agents interaction chain used to actualize CNP and establish agents trust network. We then obtain contractor's importance weight and dynamic trust by presenting fuzzy similarity-based algorithm and trust modifying algorithm, thus we propose contractor selecting approach based on maximum dynamic integrative trust. We validate the feasibility and capability of this approach by implementing simulation, analyzing compared results and checking the model.

In this paper, the problem of qualitative description and quantitative optimization for tactical reconnaissance agents system organization is considered with objective of higher teamwork efficiency and more reasonable task balancing strategies. By analyzing tactical reconnaissance system and its environment, task-(role)-entity agent mapping mechanism and agents in system organization, the system framework is qualitatively described. By transforming the system into an interaction task request-service mechanism queuing system, a Markov chain of system state transition is obtained, since its state transition process in interaction is Markov process and accords with real tactical reconnaissance behaviors. By solving the state transition equations, the inherent relationship of tactical reconnaissance agents is found and the optimized system configuration is obtained. The established simulation demonstration system proves that the proposed approach and model are feasible and effective.

FOXM1 is a critical regulator of the G1/S and G2/M cell cycle transitions, as well as of the mitotic spindle assembly. Previous studies have suggested that FOXM1 regulates CDC25A gene transcription, but the mechanism remains unknown. Here, we provide evidence that FOXM1 directly regulates CDC25A gene transcription via direct promoter binding and indirect activation of E2F-dependent pathways. Prior literature reported that CDC25B and CDC25C activate CDK1/cyclinB complexes in order to enable phosphorylation of FOXM1. It was unknown if CDC25A functions in a similar manner. We report that FOXM1 transcriptional activity is synergistically enhanced when co-expressed with CDC25A. The increase is dependent upon CDK1 phosphorylation of FOXM1 at T600, T611 and T620 residues. We also report a novel protein interaction between FOXM1 and CDC25A via the C-terminus of FOXM1. We demonstrate that the phosphorylation of Thr 600 and Thr 611 residues of FOXM1 enhanced this interaction, and that the interaction is dependent upon CDC25A phosphatase activity. Our work provides novel insight into the underlying mechanisms by which FOXM1 controls the cell cycle through its association with CDC25A.

The title compound [systematic name: 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrapropynyloxy-2,8,14,20-tetrathiacalix[4]arene], C52H56O4S4, is an alkylated product bearing four propyne groups at the lower rim of a 5,11,17,23-tetra-tert-butyl-tetrathiacalix[4]arene. The molecule is located on a crystallographic twofold rotation axis, running through two S atoms and perpendicular to the long axis of the molecule. The four propyne groups, located in an alternate fashion above and below the mean plane of the four S atoms, are almost parallel to the calixarene long axis. The dihedral angle between the two crystallographically independent benzene rings is 86.77 (14)°. Two tert-butyl groups are disordered over two positions with site occupancies of 0.59 (2) and 0.41 (2).