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The measurement of influence on online platforms has been an important issue for various applications, including viral marketing, recommender systems, and the Internet celebrity economy. Generally, the citation frequency, mention frequency, and in-degree of users are the three major criteria for evaluating online influence in existed studies. However, some online media platforms neither provide social networking functions nor support social relationship labeling, making it infeasible to measure the user influence via the above three criteria. Such platforms can be named nonexplicit-relationship platforms. In this article, we propose three new criteria, explicit conversion rate (ER), frequency of promotion (FP), and average participation density (APD), and design a novel algorithm to effectively calculate and evaluate users’ influence on these platforms. The stability and sustainability of user influence are evaluated to distinguish the real influentials from the disguised ones, while the latter usually appears for temporary commercial advertisement purposes. The experiments proved the effectiveness of the proposed criteria and the algorithm in determining influentials’ influence, as well as the corresponding stability and sustainability.

During the ongoing outbreak of coronavirus disease (COVID-19), people use social media to acquire and exchange various types of information at a historic and unprecedented scale. Only the situational information are valuable for the public and authorities to response to the epidemic. Therefore, it is important to identify such situational information and to understand how it is being propagated on social media, so that appropriate information publishing strategies can be informed for the COVID-19 epidemic. This article sought to fill this gap by harnessing Weibo data and natural language processing techniques to classify the COVID-19-related information into seven types of situational information. We found specific features in predicting the reposted amount of each type of information. The results provide data-driven insights into the information need and public attention.

BACKGROUND: To analyze the imaging features of coronary artery-to-pulmonary artery fistula (CPAF) on coronary computed tomography angiography (CCTA). METHODS: This was a retrospective study of 3,975 patients who underwent 320 row detector CCTA examinations in our hospital from May 2015 to July 2020. A total of 22 patients who diagnosed with CPAF were reviewed for CCTA imaging characteristics, including the origin, number, blood volume, opening size, and course of fistula vessels, and the drainage site, size, and imaging features of the fistula. All cases were analyzed for the presence of coronary atherosclerotic plaque and that of deficient left ventricular myocardial perfusion. RESULTS: A total of 22 CPAF cases detected by CCTA were collected (men, 11; women, 11; median age, 59.6±10.1 years). There were 7, 10, and 5 cases detected with 1, 2, and 3 fistula vessels, respectively, among which 4 originated from the left coronary artery, 4 from the right coronary artery, and 14 had bilateral origins. There were 10 cases in which the fistula vessels presented as a worm-like tortuous dilation with (n=5) or without (n=5) aneurysm, while 12 cases showed malformed vascular networks with (n=8) or without (n=4) aneurysm, respectively. The calculated incidence of aneurysm formation was 59.09%, and fistula vessels with an aneurysm had larger blood volume than those without. All fistula showed a single drainage site, with an average diameter of 2.81±1.48 mm where the diameter of fistula with aneurysm was larger than that without. The fistula vessels drained into the left anterolateral and anterior walls of main pulmonary artery and the proximal left inferior PA, respectively. Typical jet sign, smoke sign, and isodensity sign were presented in 22, 14 and 1 case, respectively. For the coexistent abnormalities analyzed in 22 cases, 17 participants with CPAF demonstrated hypoperfusion of the fistula vessels, and 11 demonstrated calcified plaque accompanied with luminal stenosis to different degrees. CONCLUSIONS: The 320-row detector CCTA can comprehensively characterize the morphological features of CPAF, which is an optimal choice for physicians to make an accurate assessment before formulating patient management strategies.

Classical Mahalanobis distance is used as a method of detecting outliers, and is affected by outliers. Some robust Mahalanobis distance is proposed via the fast MCD estimator. However, the bias of the MCD estimator increases significantly as the dimension increases. In this paper, we propose the improved Mahalanobis distance based on a more robust Rocke estimator under high-dimensional data. The results of numerical simulation and empirical analysis show that our proposed method can better detect the outliers in the data than the above two methods when there are outliers in the data and the dimensions of data are very high.

Rumor censorship of social media platforms has become an important issue in the academia and in practice. However, most studies focus on the complete rumor censorship behavior rather than the soft censorship behavior of (social media) platforms. To characterize soft censorship behavior, we conduct analytical, numerical, and experimental analyses using game theory to determine the specific strategies of platforms and rumormongers. Given that (1) the censorship behavior of platforms is costly and (2) platforms have a limited accuracy rate to identify rumors correctly, the platform may identify rumors as true information or identify true information as rumors; moreover, (3) rumormongers decide whether to publish rumors or not to avoid been deleted by the platforms. We found that (1) if deleting true information mistakenly has benefits rather than cost (the platform may cost less by not improving their rumor identification algorithms if the public pays less attention to the freedom of their speech), then platforms are more likely to censor rumormongers and delete the information they published; (2) if deleting true information is costly, then platforms become more cautious about their deleting behavior. This study explains why censoring is accepted by the public in some countries but is highly questionable in others. Using these findings can help platforms understand the rumor publishing behavior of rumormongers and make decisions based on certain situations.

Background The impacts of environmental cadmium (Cd) exposure on birth size parameters including weight, length and head circumference (HC) have been reported in multiple studies. However, little remains known of the impacts of maternal Cd exposure during pregnancy on size during in utero development and during early childhood. The aim of this study was to comprehensively investigate impacts of maternal Cd exposure during pregnancy on the size of offspring in utero (from 24 weeks pregnancy) until six months of age. Methods Pregnant mothers were recruited as part of an ongoing prospective birth cohort study based in Guangdong, China. Maternal urine samples were collected in the first and third trimesters of pregnancy, in which Cd concentrations were measured by inductively couple plasma mass spectrometry (ICPMS). In utero size indicators at 24 and 32 week of gestation, including biparietal diameter (BPD), abdominal circumference (AC), femur length (FL) and HC were derived from ultrasound examinations. Anthropometric measures of weight, height and HC at birth and one, three and six months of age were also collected. Associations of size measures at the various time points with maternal urinary Cd concentrations were assessed using linear regression models. Results The median urinary Cd concentration was 1.00 and 0.98 μg/g creatinine in the first and third trimesters respectively. In univariate analysis, increased maternal Cd levels in the first trimester were associated with decreased HC (-0.17 cm/ug/g urinary Cd) at birth, and the association was particularly pronounced among males (-0.30 cm/ug/g urinary Cd). First trimester Cd exposure was also found to be significantly associated with decreased infant weight at three and six months of age among girls (−101 g/ug/g and −97 g/ug/g urinary Cd, respectively). Associations of similar magnitude were observed after adjustment for various maternal factors. No significant associations were observed with infant size measures or with measures of Cd in the third trimester. Conclusions Our detailed study suggests that the first trimester is particularly critical window of susceptibility to sex-specific effects of Cd on size parameters at birth, with some effects persisting to six months of age. These compelling sex-dependent effects on HC and body weight warrant future studies examining longer-term health effects of pregnancy-related Cd exposures.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a newly identified strain of coronavirus in the human body and was reported in Wuhan at the end of 2019. So far, the epidemic is continuing and very serious, with the number of infections and deaths increasing. Despite active investigations around the world to better understand the dynamics of transmission and the scope of clinical disease, COVID-19 continues to spread rapidly from person to person. The common signs and symptoms of SARS-CoV-2 infection include fever, fatigue, dry cough, and dyspnea; in severe cases, patients may have acute respiratory distress syndrome, septic shock, metabolic acidosis difficult to treat and coagulation disorder. However, some patients who test positive for SARS-CoV-2 in their respiratory tract may not have such clinical signs and symptoms. This report presents a case study analysis of a patient admitted in the Fourth Taiyuan People's Hospital, who had suffered traumatic injuries from a car accident and survived COVID-19, with pleural effusion as the initial symptom. We report a case of 2019-NCOV with pleural effusion as the first symptom. Describe in detail the differential diagnosis, diagnosis, clinical management, and cure of this case. In order to combat the novel CoronaviruscoVID-19 in the process to provide lessons and help.

Lead-free halide perovskite nanocrystals (NCs) have caused widespread concerns for solving the toxicity and instability problems of lead perovskites. Here, we synthesized Al3+-Cs2AgBiCl6. Through controlling the doping content of Al3+ ions, the Al3+-Cs2AgBiCl6 exhibit bright self-trapped exciton (STE) red emission. The photoluminescence quantum efficiency (PLQY) increases significantly from 0.98% to 17.2%, which is higher than the record value (16%) of the currently reported red-emitting lead-free double perovskite. The enhancement of PL of NCs is accomplished by indirect to direct bandgap transition assisted by doping of Al3+ ions, as supported by density functional theory (DFT) calculations. Moreover, the Al3+-Cs2AgBiCl6 exhibit ultrahigh stability and can maintain their original structure for more than 7 months, which demonstrates the best stability comparing with the reported double perovskite nanocrystals. Finally, the white light emitting diode (WLED) was fabricated. These results provide opportunities for the future application of lead-free double perovskite in the field of optoelectronics.

In this study, a series of spatial single-loop overconstrained linkages (SLOLs) is synthesized using Bennett linkages as the basic units. A set of 5R and 6R single-loop kinematic chains is constructed by combining Bennett linkages. The motion screw equations of these kinematic chains are obtained. Using screw theory their mobility is analyzed. Linkages with zero joint offset are constructed to create mechanisms with excellent deployability. The deployability of the SLOLs with symmetric configurations and their relationship with Bricard linkages are investigated. The symmetry of the obtained linkages is evaluated, and several linkages with line symmetry and plane symmetry are generated. Results show that a part of the synthesized linkages has excellent deployability and can serve as the units of deployable mechanisms. Intersections exist between the Bennett-based SLOLs and Bricard linkages.

We developed a Multinomial Nave Bayes Classifier to categorize the microblog posts into five types according to the text content of posts.Different types of information had significantly different propagation patterns in terms of scale and topological features.Social media users exhibited significantly different interaction patterns for different types of information at different stages. Social media has been playing an increasingly important role in information publishing and event monitoring in emergencies like natural disasters. The propagation of different types of information on social media is critical in understanding the reaction and mobility of social media users during natural disasters. In this research, we analyzed the dynamic social networks formed by the reposting (retweeting) behaviors in Weibo.com (the major microblog service in China) during Yiliang Earthquake. We developed a Multinomial Nave Bayes Classifier to categorize the microblog posts into five types based on the content, and then characterized the information propagation patterns of the five types of information at different stages after the earthquake occurred. We found that the type of information has significant influence on the propagation patterns in terms of scale and topological features. This research revealed the important role of information type in the publicity and propagation of disaster-related information, thus generated data-driven insights for timely and efficient emergency management using the publicly available social media data.

Recently, photodetectors based on perovskite nanomaterials have attracted considerable attention in the visible spectral region owing to their large absorption coefficients, long diffusion lengths and high optical gains. However, the fabrication of self-powered visible-blind ultraviolet (UV) photodetectors is still challenging for the perovskite nanomaterials. This work developed the self-powered UV photodetector based on the Eu(AcO)3 promoted CsPbCl3 nanowires (NWs), enabled by the great separation efficiency of electron-hole pairs and high electron mobility of the one-dimentional (1D) morphology of perovskite materials. The perovskite CsPbCl3 NWs were synthesized by a modified hot-injection method with assistant of Eu(AcO)3 additive. As supported by the experimental investigations and DFT calculations, the adsorption of Eu3+ and AcO− ions to the surface of perovskite not only promotes the anisotropic growth of perovskite in (2 0 0) orientation, but also efficently passivates the halide defect of the perovskite nanomaterials. Moreover, the self-powered UV photodetector based on the Eu(AcO)3 promoted CsPbCl3 NWs displays a high responsivity of 398 mA W−1, detectivity up to 3.3 × 1011 Jones and fast response speed (24 ms) at 360 nm without external bias. The responsivity and detectivity of the device based on CsPbCl3 NWs are improved 8 and 205 times, comparing with the device based on bare CsPbCl3 NCs without passivation, respectively. In addition, the detectivity is comparable to some previous reports about perovskite NC-based UV photodetectors with additional bias. Our findings demonstrate the promising potential of 1D perovskite NWs for developing the next-generation self-powered UV photodetectors.

In this study, the networking method of Bennett linkages is investigated, and a deployable parabolic cylindrical antenna is constructed based on the network. The alternative form of Bennett linkage has excellent performance in terms of deployment and folding. Using the alternative form as basic units, a networking method of Bennett linkage is proposed. In the network, the units are parallel in one direction and have an included angle in the vertical direction. Thereafter, the mobility of the mechanical network is analyzed through screw theory. Results show that the network has one degree of freedom, and that the included angle has no effect on network mobility. According to this property, a method of constructing parabolic cylindrical antennas is proposed. The parameters of units in the network are then analyzed. A parabolic cylindrical antenna is designed, and a prototype is constructed. The parabolic cylindrical antenna proposed in this study can be folded completely and can be deployed to the predetermined profile. This study provides a novel industrial application of the classical Bennett linkage.

Endothelial cell (EC) apoptosis contributes to cigarette smoke (CS)-induced pulmonary emphysema. Metabolism of glucose, glutamine, and fatty acid is dysregulated in patients with chronic obstructive pulmonary disease (COPD). Whether CS causes metabolic dysregulation in ECs leading to development of COPD remains elusive. We hypothesized that CS alters metabolism, resulting in apoptosis in lung ECs. To test this hypothesis, we treated primary mouse pulmonary microvascular ECs (PMVECs) with CS extract (CSE) and employed PMVECs from healthy subjects and COPD patients. We found that mitochondrial respiration was reduced in CSE-treated PMVECs and in PMVECs from COPD patients. Specifically, oxidation of fatty acids (FAO) was reduced in these cells, which linked to reduced carnitine palmitoyltransferase 1a (Cpt1a), an essential enzyme for carnitine shuttle. CSE-induced apoptosis was further increased when cells were treated with a specific Cpt1 inhibitor etomoxir or transfected with Cpt1a siRNA. L-Carnitine treatment augmented FAO but attenuated CSE-induced apoptosis by upregulating Cpt1a. CSE treatment increased palmitate-derived ceramide synthesis, which was reduced by L-carnitine. Although CSE treatment increased glycolysis, inhibiting glycolysis with 2-deoxy-d-glucose had no effects on CSE-mediated apoptosis in lung ECs. Conclusively, FAO reduction increases ceramide and apoptosis in lung ECs treated with CSE, which may contribute to the pathogenesis of COPD/emphysema.

Background Acute myocardial infarction (AMI) is a server disease effecting a large population worldwide. The pathophysiological process of ischemic/reperfusion (I/R) plays an important role for heart tissue damage. VO-OHpic, a PTEN inhibitor, has been demonstrated to be cardiac protective in sudden cardiac arrest models, but its role in AMI remains unclear. Methods An isolated AMI model was induced by dissecting the rat heart in a Langendorff system. Cardiac myocytes were extracted and induced ischemia in vitro. VO-OHpic was added into the above systems. The area of infarcted tissue in the heart was measured. Cardiac myocyte apoptosis was assessed by flow cytometry. Activation of Akt and GSK3β was quantified by flow cytometry. IL-10 levels were determined by ELISA. Results VO-OHpic reduced infarcted areas in the isolated heart, and improved cultured cardiac myocyte survival. VO-OHpic induced apoptosis resistance in cardiac myocytes. Akt-GSK3β signaling was activated by VO-OHpic administration. IL-10 levels in the medium were elevated by VO-OHpic. Conclusion VO-OHpic protects heart tissue by apoptosis resistance via activating Akt-GSK3β signaling and increasing IL-10 levels.

In this paper, we take the urban road network as the object, a further study on the method of traffic signal self organization under the condition of traffic state identification and local congestion. In the urban road traffic state identification study, according to the need of traffic signal control, respectively from qualitative and quantitative point of view, the urban road traffic state is defined. In order to be able to obtain real-time traffic data as the foundation, design urban road traffic state evaluation index system. Based on the current mainstream micro traffic simulation software VB and VISSIM as the tool to build the experimental platform, and set up the UTC-CI (Urban Traffic Control for Congested Intersections) experimental environment, the above method is verified by simulation. The results show that the traffic state identification method and the related signal control method have the expected effect in reducing congestion duration.

INTRODUCTION Chronic obstructive pulmonary disease (COPD) is a frequent comorbid disease in patients undergoing coronary artery bypass grafting (CABG) surgery, with an incidence ranging from 4% to 20.5%. Conventionally, COPD was recognized as a surgical contraindication to CABG. Because of the recent improvements in surgical techniques, anesthesia, and postoperative management, CABG has been performed more commonly in patients with COPD. However, studies have shown the various effects of COPD on postoperative morbidity and mortality after CABG, and this remains to be well defined. OBJECTIVES To compare the postoperative outcomes after CABG between patients with and those without COPD. METHODS A systematic search was conducted in the Cochrane Library, PubMed, EmBase, and Ovid databases (until May 10, 2018). Studies comparing perioperative results and mortality outcomes after CABG between patients with and those without COPD were evaluated independently by 2 reviewers to identify the potentially eligible studies. Review Manager and STATA software were used for statistical analyses. RESULTS No significant difference in the mortality rates were found between patients with and those without COPD. COPD was associated with a higher respiratory failure rate (odds ratio [OR] = 4.01; 95% CI: 1.19-13.51, P = .03; P

Large parabolic dish concentrator mirrors are an important component of many solar energy systems. They need to be relatively precise and are expensive to fabricate and to transport. Here, a new concept for designing and fabricating large parabolic dish mirrors is presented. The dish mirror is formed from several optimal-shaped thin flat metal petals with highly reflective surfaces. Attached to the rear surface of the mirror petals are several thin layers whose shapes are optimized to have reflective petals form into a parabola when their ends are pulled toward each other by cables or rods. An analytical model to optimize the shape and thickness of the petals is presented. The validity of the concept is demonstrated using Finite Element Analysis and laboratory experiments. The concept would permit flat mirror elements to be easily fabricated and efficiently packaged for shipping to field sites where they can be assembled into the parabolic dish concentrators. The concept has the potential to provide precision solar parabolic solar collectors at a substantially lower cost than conventional methods.

BACKGROUND: Gait recovery is very important to stroke survivors to regain their independence in activity of daily life. OBJECTIVE:This study aimed to investigate the effects of virtual reality (VR) coupled body weight support treadmill training (BWSTT) on pelvic control at the early stage of stroke. METHODS: Kinematic and kinetic changes of pelvic motion were evaluated by a 3D gait analysis system and were compared to the results from over-ground walking training. Twenty-four patients having unilateral hemiplegia with subacute stroke were recruited to a VR coupled BWSTT group (n = 12) and a conventional therapy (CT) group (n = 12). Both of the groups received training of 20–40 min/day, 5 days/week, for 3 weeks. RESULTS: The results showed the tilt of pelvis in sagittal plane improved significantly (P = 0.038) after treatment in the BWSTT+VR group, in terms of decreased amplitude of anterior peak (mean, from 10.99 ◦ to 6.25 ◦ ), while there were no significant differences in the control group. CONCLUSION: The findings suggested that VR coupled BWSTT gait training could decrease anterior tilt of pelvis in early hemiparetic persons following a modest intervention dose, and the training may have advantages over conventional over-ground gait training and can assist the therapists in correcting abnormal gait pattern of stroke survivors.

Wearable robotic devices provide safe and intensive rehabilitation, enabling repeated motions for motor function recovery in stroke patients. The aim of this small case series was to demonstrate the training effects of a three-week robotic leg orthosis, and to investigate possible mechanisms of the sensory-motor alterations and improvements by using gait analysis and EMG. Three survivors of chronic strokes participated in robot-assisted gait therapy for three weeks. EMG signals from the rectus femoris (RF), tibialis anterior (TA), biceps femoris (BF), and medial gastrocnemius (MG), as well as kinetics and kinematics data of the lower limb, were recorded before and after the training. The normalized root mean squared (RMS) values of the muscles, the joint moments, joint angles, and the results of two clinical scales (Berg Balance scale, BBS, and the lower extremity subscale of Fugl-Meyer assessment, LE-FMA) were used for analysis. All participants experienced improved balance and functional performances and increased BBS and LE-FMA scores. The EMG results showed there was an increase of the normalized RMS values of the MG and BF on the affected side. Additionally, EMG activities of the agonist and antagonist pair (i.e. RF and BF) appeared to return to similar levels after training. The peak moment of hip flexor, knee extensor, and plantar flexor, which all contributed to push-off power, were found to have increased after training. In summary, the three-week training period using the wearable RLO improved the three participants' gait performance by regaining push-off power and improved muscle activation and walking speed.

A novel active gravity compensation concept is proposed to simulate space on-orbit microgravity environments for free-flying robots on ground. Here, robots are suspended by active-controlled motion path tracking mechanisms through wires to compensate for gravitational forces. Based on the concept, an experimental test bed was designed and fabricated in laboratory to study on-ground kinematic and dynamic behaviors of a free-flying robot. The experimental fabrication contains an active horizontal motion tracking mechanism composed of primary and secondary active rotating arms. An multi-objective optimization method calculating the tension of the wires to minimize torques on robot joints is approved. The tension of the suspension wires is obtained through passive counterweights using pulley mechanisms. The kinematics and dynamics of a 6-DOF free-flying manipulator were calculated in MATLAB and simulated in MSC Adams under three working conditions: zero-gravity, gravity compensation and gravity. The lowest ratio of the torque compensation reached 80%. Agreements between numerical analyses and simulation results confirm the ability of this gravity compensation concept to simulate the kinematic and dynamic behaviors of free-flying manipulator in space.

We derive the outage capacity region of an M-user fading multiple-access channel (MAC) under the assumption that both the transmitters and the receiver have perfect channel side information (CSI). The outage capacity region is implicitly obtained by deriving the outage probability region for a given rate vector. Given a required rate and average power constraint for each user, we find a successive decoding strategy and a power allocation policy that achieves points on the boundary of the outage probability region. We discuss the scenario where an outage must be declared simultaneously for all users (common outage) and when outages can be declared individually (individual outage) for each user.

Based on The Internet of Things, Radio frequency identification (RFID) has introduced into the University Library Management. The resource sharing can be implemented through internet. Moreover, the book resource and management style has been integrated and optimized. A variety of functions can be achieved by the Internet of Things, including self-borrowing and self-returning, smart inventory, intelligent query, combination of books and information system. Consequently, human-based management and service has been provided to help borrows obtain the necessary knowledge and meet their demands.

For pt.I see ibid., vol.47, no.3, p.1083-1102 (2002). We study three capacity regions for fading broadcast channels and obtain their corresponding optimal resource allocation strategies: the ergodic (Shannon) capacity region, the zero-outage capacity region, and the capacity region with outage. In this paper, we derive the outage capacity regions of fading broadcast channels, assuming that both the transmitter and the receivers have perfect channel side information. These capacity regions and the associate optimal resource allocation policies are obtained for code division (CD) with and without successive decoding, for time division (TD), and for frequency division (FD). We show that in an M-user broadcast system, the outage capacity region is implicitly obtained by deriving the outage probability region for a given rate vector. Given the required rate of each user, we find a strategy which bounds the outage probability region for different spectrum-sharing techniques. The corresponding optimal power allocation scheme is a multiuser generalization of the threshold-decision rule for a single-user fading channel. Also discussed is a simpler minimum common outage probability problem under the assumption that the broadcast channel is either not used at all when fading is severe or used simultaneously for all users. Numerical results for the different outage capacity regions are obtained for the Nakagami-m (1960) fading model.

The purpose of this study was to determine whether estrogen and progesterone influence fast glucocorticoid negative feedback regulation of the ACTH and corticosterone (CORT) responses to stress. Mature rats were ovariectomized and 6 weeks later implanted with 17 beta-estradiol (E2, 0.5 mg), E2 and progesterone (P, 100 mg; E2 + P group) or placebo pellets (OVX). Seven days later rats were subjected to a single or repeated intermittent footshock stress (0.2 mA, 15 s duration, 0.5 s on). The repeated stress was of the same intensity and duration, and was applied either during the time domain of the rate-sensitive fast glucocorticoid feedback when plasma CORT levels are rising (5 min after the onset of the first stress), or at the time of peak CORT response (15 min) to the initial stress. Plasma ACTH and CORT were measured from serial samples. Estrogen replacement alone or in combination with progesterone lowered the immediate (t = 5) ACTH and CORT response to a single stress in ovariectomized animals. The second stress applied 5 min after the initial stress produced net ACTH responses similar to those obtained after a single stress in the OVX and E2 + P-replaced hormone groups, while total ACTH responses were lower in the E2-treated group. In ovariectomized animals, a facilitation of ACTH response by a prior stress is apparent in response to a footshock 15 min later, when the integrated ACTH secretion is significantly greater than the response measured after a single shock, or after a repeated shock 5 min apart. Anterior pituitary proopiomelanocortin (POMC) mRNA levels were lower in groups with E2 or E2 + P replacement compared to OVX animals. In contrast, hypothalamic corticotropin-releasing factor (CRF) mRNA levels did not increase significantly. However, hypothalamic glucocorticoid receptor (GR) mRNA levels increased after 17 beta-estradiol treatment, and this increase was reversed by progesterone. These results suggest that prior stress leads to both a fast-feedback inhibition and a facilitation of the subsequent stress response. In the absence of gonadal hormones this facilitation is balanced by fast-feedback inhibition during the glucocorticoid fast-feedback time domain, and is unmasked outside of this time domain. Estrogen suppresses POMC mRNA synthesis leading to a decrease in the availability of releasable ACTH, thereby reducing the facilitation. Progesterone may counter this effect of estrogen by decreasing the efficacy of the fast rate-sensitive glucocorticoid negative feedback.

Parabolic concentrator mirrors are an important component of many solar energy systems, particularly solar mirror collectors. Precision parabolic mirrors are expensive to fabricate and to transport. Here, a new concept for designing and fabricating precision parabolic mirrors is presented. The mirror is formed from a thin flat very flexible metal sheet with a highly reflective surface. Attached to the rear surface of the mirror sheet is a backbone band whose figure is optimized to form the reflective sheet into a precision parabola when its two ends are pulled toward each other. An analytical model to optimize the shape and thickness of the band is presented. The validity of the concept is demonstrated using Finite Element Analysis (FEA) and laboratory experiments. The concept would permit flat mirror elements to be easily fabricated and efficiently packaged and shipped to field sites and assembled into the parabolic trough concentrators with potentially substantial costs reductions compared with the conventional methods.

Parabolic concentrator mirrors are an important component of many solar energy systems, particularly solar mirror collectors. Precision parabolic mirrors are expensive to fabricate and to transport. Here, a new concept for designing and fabricating precision parabolic mirrors is presented. The mirror is formed from a thin flat very flexible metal sheet with a highly reflective surface. Attached to the rear surface of the mirror sheet is a backbone band whose figure is optimized to form the reflective sheet into a precision parabola when its two ends are pulled toward each other. An analytical model to optimize the shape of the band is presented. The validity of the concept is demonstrated using Finite Element Analysis and laboratory experiments. The concept would permit flat mirror elements to be easily fabricated and efficiently packaged and shipped to field sites and assembled into the parabolic trough concentrators with potentially substantial costs reductions compared with conventional methods.Copyright © 2011 by ASME

it seems to be a trend that mobile phone is becoming the "portable newsstand" and "portable library" of the mordern people. Accordingly, the huge business opportunities related with mobile phone reading and mobile phone publishing applications have brought along the enthusiasm and initiative of network operators, literary sites, traditional publishers, authors, readers and other areas. This paper carries out a reseach on the characteristics of mobile phone literary and the efforts having made at home and abroad on mobile phone reading and the problems and obstacles still exsiting in this field.

The media environment has become another very important factor in the social environment and has become the most important “modeling power” in modern society. Profit orientation of media and market competitive pressures, as well as the extremely poor public media literacy endows media education with the necessity and urgency. This paper studies on the content of media literacy education and implementation strategies of media literacy education.

OBJECTIVE Oxidative stress is a major contributing factor in the development of diabetic nephropathy. Peroxisome proliferator–activated receptor γ heterozygous mice and Pro12Ala polymorphism in PPARG exhibited increased resistance to oxidative stress. Smoking increases the production of reactive oxygen species, which accelerates oxidative stress under hyperglycemia. To determine whether the Pro12Ala polymorphism, alone or in combination with smoking, contributes to the development of diabetic nephropathy, a case-control study was performed in 760 Chinese patients with type 2 diabetes. RESEARCH DESIGN AND METHODS Among patients, 532 had diabetic nephropathy with microalbuminuria (n = 245) or overt albuminuria (n = 287), and 228 did not show either of these symptoms but had had diabetes for ≥10 years and were not undergoing antihypertension treatment. RESULTS After adjustment for confounders, the Pro/Pro genotype was significantly associated with diabetic nephropathy (odds ratio 2.30 [95% CI 1.18–4.45], P = 0.014); smoking was also an independent risk factor for diabetic nephropathy (1.99 [1.08–3.68], P = 0.029). In addition, we identified possible synergistic effects; i.e., the high-risk group (smokers with the Pro/Pro genotype) showed 4.52 times higher risk (1.78–11.48, P = 0.002) of diabetic nephropathy than the low-risk group (nonsmokers with the Pro/Ala genotype) in a multiple logistic regression analysis controlled for the confounders. CONCLUSIONS Our results indicated that the Pro/Pro genotype and smoking were significant independent risk factors for diabetic nephropathy. The possible synergistic effects of genotype and smoking may aggravate oxidative stress and contribute to the development of diabetic nephropathy.

Vibration analysis is an important route for improving the driving smoothness and stability of lunar rover. The structure characteristic of the eight-wheel lunar rover with tension-bar and rocker structure is that the ground flatness inputs of each two wheels hinged by the same rocker are intercoupling. The ground flatness excitation is equivalently transformed, which is the main excitation source, then the equivalent ground flatness function is obtained and, the vibration model and differential equation of the vibration system of the 7 DOF lunar rover are established. The differential equation of the vibration system is solved by Gaussian elimination and Runge-Kutta numerical method after Fourier transformation. The amplitude-frequency characteristic curve of the bodywork center of mass, the amplitude-frequency characteristic curve of vibration acceleration, and the relation curve between damps and the root mean square of the suspension flexibility were got by programming by means of Matlab. The driving smoothness and stability of the lunar rover is analyzed. The factors in the driving smoothness and stability are pointed out. And the variation range of damps for improving the driving smoothness and stability is presented.

Pragmatic trellis-coded modulation (P-TCM) scheme uses the same single coder and decoder for various codes which have a performance comparable to that of Ungerboeck codes on a linear Gaussian channel. The performance on Rician fading and light shadowed Rician fading channels of a rate 2/3, 64-state P-TCM code is studied. Upper bounds, lower bounds and asymptotic approximation of bit error rate (BER) with both coherent detection and differential detection are estimated. Computer simulation results are also given. The results show that there are about a 3.4-5.2 dB coding gain of this code on the above mentioned channels at a BER=10/sup -3/.

We derive the optimal power allocation and minimum outage probability for fading multiple-access channels under the assumption that both the transmitters and the receiver have perfect channel side information. This minimum outage probability implicitly defines the outage capacity region. Two different assumptions about whether the outage declaration from each user is simultaneous or independent are considered.

We derive the outage capacity regions of fading broadcast channels for code-division (CD), time-division (TD) and frequency-division (FD), assuming that both the transmitter and the receivers have perfect channel side information. The zero-outage capacity regions and the associate optimal resource allocation policies are obtained for CD with and without successive decoding, for TD and for FD. We show that in an M-user broadcast system, the outage capacity region is implicitly obtained by deriving the outage probability region for a given rate vector. Given the required rate of each user, we find a strategy which bounds the outage probability region for different spectrum-sharing techniques. The corresponding optimal power allocation scheme is a multi-user generalization of the threshold-decision rule for a single-user fading channel. Also discussed is a simpler minimum common outage probability problem under the assumption that the broadcast channel is either not used at all when fading is severe or used simultaneously for all users. Numerical results for various outage capacity regions are obtained for the Nakagami-m fading model.

W18O49 nanowires have been intensively studied in recent years due to their good field emission (FE) performances. However, now their development has encountered difficulties, i.e., their emission uniformity is not good enough for high resolution field emission display (FED) applications. Here, we have successfully fabricated patterned, large-scale W18O49 nanowire vertical-arrays and for the first time applied an in situ plasma treatment technique to improve their field emission performance. It is found that their emission uniformity has been improved to a very high level (distribution uniformity of emission sites is higher than 96% and their brightness uniformity reaches 75.64%), while other emission properties remained unchanged compared to untreated nanowires. The bombardment of Ar plasma and the reduction of H2 plasma may be responsible for the improvement of their FE performance. It can be concluded that this developed technique is a very effective route to enhance the emission uniformity of patterned W18O49 nanowire arrays, which may pave the way for FE emission behavior improvement of other metal oxide nanowires.

Ultra-long AlN nanowire arrays are prepared by chemical vapor deposition, and the photoconductive performances of individual nanowires are investigated in our self-built measurement system. Individual ultra-long AlN nanowire (UAN) exhibits a clear photoconductive effect under different excited lights. We attribute the positive photocurrent response of individual UAN to the dominant molecular sensitization effect. It is found that they have a much faster response speed (a rise and decay time of about 1 ms), higher photocurrent response (2.7×106), and more reproductive working performance (the photocurrent fluctuation is lower than 2%) in the air environment. Their better photoconductive performances are comparable to many nanostructures, which are suggested to be a candidate for building promising photosensitive nanodevices in the future.