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In this paper, two different discrete schemes of the second-order linear time-varying system represented by the linearized satellite magnetic attitude control motion equation are obtained by Euler method. Then, the controllability and observability conditions of a new discrete second-order linear time-varying system are proposed and the validity of these conditions is further verified by some numerical examples. Next, the theoretical results are applied to investigate the controllability and observability of the discretized satellite magnetic control system. Different periods $ \tau $ are chosen to investigate the effect on the controllability and observability of the resulting discrete system. The corresponding conclusions are obtained.

Studying plant early immunity, such as the unique immune mechanisms against pathogens, is an important field of research. Tomato wilt resulting from the infection by Fusarium oxysporum f. sp. lycopersici (Fol) is an important soil-borne vascular disease. In this study, we challenged tomato plants with Fol for a time-course RNA sequencing (RNA-seq) analysis. The result indicated that phenylpropanoid and flavonoid pathway genes were significantly enriched during the early invasion stage. Further study revealed that the flavonoids galangin and quercetin could effectively inhibit Fol growth and enhance wilt resistance in tomato. Moreover, the genes involved in plant-pathogen interactions, the MAPK signaling pathway, and plant hormone signal transduction were significantly enriched. These genes were also involved in plant pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) signaling pathways. Strikingly, the transcription levels of pathogen-related protein 1 (SlPR1) were dramatically increased at 2 days post Fol inoculation, implying that SlPR1 is important in early immunity in tomato. SlPR1 does not have direct antifungal activity. Instead, its C-terminal peptide CAPE1 could activate root defense responses, such as the reactive oxygen species (ROS) burst, salicylic acid (SA)/jasmonic acid (JA) production, and defense-related gene expression, which collectively increased tomato resistance to Fol infection. In addition, CAPE1 could induce systemic acquired resistance (SAR). Application of CAPE1 onto tomato leaves induced local resistance to the pathogen Botrytis cinerea and systemic resistance to Fol infection. These results advanced our understanding for the early immunity against Fol in tomato and provide potential strategy for tomato disease control.

Background Medical device-related pressure injuries(MDRPI) are prevalent and attracting more attention. During ambulance transfer, the shear force caused by braking and acceleration; extensive medical equipment crowed in a narrow space add external risk factors for MDRPIs. However, there is insufficient research on the relationship between MDRPIs and ambulance transfers. This study aims to clarify the prevalence and characteristics of MDRPI during ambulance transfer. Method A descriptive observational study was conducted with convenience sampling. Before starting the study, six PI specialist nurses certified by the Chinese Nursing Association trained emergency department nurses for three MDRPI and Braden Scale sessions, one hour for each session. Data and images of PIs and MDRPIs are uploaded via the OA system by emergency department nurses and reviewed by these six specialist nurses. The information collection begins on 1 July 2022 and ends on 1 August 2022. Demographic and clinical characteristics and a list of medical devices were collected by emergency nurses using a screening form developed by researchers. Results One hundred one referrals were eventually included. The mean age of participants was (58.3 ± 11.69) years, predominantly male (67.32%, n = 68), with a mean BMI of 22.48 ± 2.2. The mean referral time among participants was 2.26 ± 0.26 h, the mean BRADEN score was 15.32 ± 2.06, 53.46% (n = 54) of participants were conscious, 73.26% (n = 74) were in the supine position, 23.76% (n = 24) were in the semi-recumbent position, and only 3 (2.9%) were in the lateral position. Eight participants presented with MDRPIs, and all MDRPIs are stage 1. Patients with spinal injuries are most prone to MDRPIs (n = 6). The jaw is the area most prone to MDRPIs, caused by the cervical collar (40%, n = 4), followed by the heel (30%, n = 3) and nose bridge (20%, n = 2) caused by the respiratory devices and spinal board. Conclusion MDRPIs are more prevalent during long ambulance referrals than in some inpatient settings. The characteristics and related high-risk devices are also different. The prevention of MDRPIs during ambulance referrals deserves more research.

Pathogens utilize secretory effectors to manipulate plant defense. Fusarium oxysporum f. sp. lycopersici (Fol) is the causal agent of Fusarium wilt disease in tomatoes. We previously identified 32 secreted effector candidates by LC-MS analysis. In this study, we functionally identified one of the secreted proteins, FolAsp, which belongs to the aspartic proteases (Asp) family. The FolAsp was upregulated with host root specifically induction. Its N-terminal 1–19 amino acids performed the secretion activity in the yeast system, which supported its secretion in Fol. Phenotypically, the growth and conidia production of the FolAsp deletion mutants were not changed; however, the mutants displayed significantly reduced virulence to the host tomato. Further study revealed the FolAsp was localized at the apoplast and inhibited INF1-induced cell death in planta. Meanwhile, FolAsp could inhibit flg22-mediated ROS burst. Furthermore, FolAsp displayed protease activity on host protein, and overexpression of FolAsp in Fol enhanced pathogen virulence. These results considerably extend our understanding of pathogens utilizing secreted protease to inhibit plant defense and promote its virulence, which provides potential applications for tomato improvement against disease as the new drug target.

Background Medical device-related pressure injuries(MDRPI) are prevalent and attracting more attention. During ambulance transfer, the shear force caused by braking and acceleration; extensive medical equipment crowed in a narrow space add external risk factors for MDRPIs. However, there is insufficient research on the relationship between MDRPIs and ambulance transfers. This study aims to clarify the prevalence and characteristics of MDRPI during ambulance transfer. Method A descriptive observational study was conducted with convenience sampling. Before starting the study, six PI specialist nurses certified by the Chinese Nursing Association trained emergency department nurses for three MDRPI and Braden Scale sessions, one hour for each session. Data and images of PIs and MDRPIs are uploaded via the OA system by emergency department nurses and reviewed by these six specialist nurses. The information collection begins on 1 July 2022 and ends on 1 August 2022. Demographic and clinical characteristics and a list of medical devices were collected by emergency nurses using a screening form developed by researchers. Results One hundred one referrals were eventually included. The mean age of participants was (58.3±11.69) years, predominantly male (67.32%, n=68), with a mean BMI of 22.48±2.2. The mean referral time among participants was 2.26 ± 0.26 hours, the mean BRADEN score was 15.32 ± 2.06, 53.46% (n=54) of participants were conscious, 73.26% (n=74) were in the supine position, 23.76% (n=24) were in the semi-recumbent position, and only 3 (2.9%) were in the lateral position. Eight participants presented with MDRPIs, and all MDRPIs are stage 1. Patients with spinal injuries are most prone to MDRPIs (n=6). The jaw is the area most prone to MDRPIs, caused by the cervical collar (40%, n=4), followed by the heel (30%, n=3) and nose bridge (20%, n=2) caused by the respiratory devices and spinal board. Conclusion During long ambulance referrals, the prevalence of MDRPIs is higher than in some inpatient settings. The characteristics and related high-risk devices are also different. The prevention of MDRPIs during ambulance referrals deserves more research.

Background:New T-shaped volar locking plates (VLPs) and variable-angle volar locking plates (VLPs) are utilized for the internal fixation of distal radius fractures (DRFs). However, studies regarding the difference in clinical outcomes between these two plates are limited. The purpose of the present study was to compare postoperative outcomes between these two plate types for DRFs. Materials and Methods: A total of 45 consecutive patients (23 patients with new T-shaped VLPs and 22 patients with variable-angle VLPs) who underwent surgical treatment for DRFs were reviewed for this retrospective study. The range of motion (ROM), grip strength, visual analogue scale (VAS) pain score, X-ray findings, complication rate, fracture healing time and patient satisfaction with current activity were compared. Results: The analysis of wrist ROM revealed that there were no statistically significant differences (p > 0.05) in extension, flexion, ulnar deviation, radial deviation, supination, pronation or grip strength between the two groups. There were no statistically significant differences (p > 0.05) between the two groups with regard to alignment and fracture healing on X-ray. The final VAS pain score and patient satisfaction with current activity differed between the two groups. The complication rate in the variable-angle VLP group was significantly different from the 0% rate observed in the new T-shaped VLP group (P < 0.05). Conclusions: Although use of the new T-shaped VLP for the treatment of DRFs did not show superiority in functional outcomes or radiological findings over variable-angle VLPs, the present findings showed that internal fixation of unstable DRFs using the new T-shaped VLP yielded better clinical results with fewer complications.

Background China's PEMS system was established in the 1980s. Due to economic and resource inequalities, China's PEMS system does not have a uniform mode, and regions developed their models based on their circumstances, incorporating North America’s and Europe’s experiences. In the Sichuan PEMS model, when someone calls "120" for a pre-hospital emergency, he/she will first access the Medical Emergency Center, a dispatcher will record the incident information and makes a preliminary judgment, then that information and the judgment will be forwarded to a nearby general hospital, which will send an ambulance staffed by medical workers to provide PEMS. Instead, some people prefer to call hospitals directly for pre-hospital emergencies and communicate directly with medical staff. Which call mode is better has long been a point of contention. Methods This retrospective study included a total of 496 PEMS within 8 km of the participating hospital between 2020 and 2021. Cases that called the Emergency Medical Center dispatcher were classified as "referral group" (n = 318) and cases that called the hospital and communicated directly with medical personnel were classified as "direct group" (n = 178), and appropriate metrics were selected to measure efficiency and information accuracy Results There was no significant difference in the efficiency of PEMS between the two groups, but there was a notable difference in the information accuracy between the two groups on all indicators Conclusion Compared with calling ‘120’, direct PEMS calls to general hospitals have obvious advantages in terms of information accuracy. Perhaps the Emergency Medical Center in Sichuan could try to reform as a supervisory agency for PEMS instead of a dispatch agency or adopt the Shenzhen EMS model where the Emergency Medical Center, after receiving a call for help, transfers the call to the appropriate hospital based on the caller's location and situation, allowing the caller to communicate directly with medical personnel.

Learning a good graph similarity matrix in data clustering is very crucial. The goal of clustering is to construct a good graph similarity matrix such that the similarity of points between the same classes is largest, and the similarity of points between different classes is smallest. In this paper, a more efficient subspace segmentation approach to learn a similarity matrix with large spectral gap is proposed. In our model, a robust self-representation coefficient matrix is learned by utilizing the Schatten- ${p}$ norm instead of the conventional rank function. Besides, the fast block-diagonal structure of the coefficient representation matrix is enhanced by learning and optimizing the co-association matrix with the soft label of clustering results simultaneously in a unified framework. The affinity graphs constructed in this paper can clearly reveal the intrinsic structures of the data sets. Extensive experiments on the real data sets demonstrate that our proposed method can perform better than the state-of-the-art methods.

Background The introduction of chest pain centers (CPC) in China has achieved great success in shortening the duration of nursing operations to significantly improve the treatment and outcomes of patients with ST-segment elevation myocardial infarction (STEMI). The nursing handover period is still considered the high incidence period of adverse events because of the distractibility of nurses’ attention, potential interruption, and unclear responsibilities. Under the CPC mechanism, the nursing efficiency and patients’ outcome, whether affected by the nursing handover, is still a knowledge gap in research. This is also the aim of this study. Methods A retrospective study was conducted with data from STEMI patients from a tertiary hospital in the north of Sichuan Province from January 2018 to December 2019 through the Chinese CPC database. Patients are divided into handover and non-handover groups according to the time they presented in the Emergency Department. D2FMC, FMC2FE, FMC2BS, FMC2CBR, FMC2FAD, and D2W were selected to measure nursing efficiency. The occurrence of major adverse cardiovascular events, the highest troponin values within 72 h of hospitalization, and the length of hospitalization were selected to measure the patient outcomes. Continuous variables are summarized as mean ± SD, and t-tests of the data were performed. P-values Results A total of 231 cases were enrolled, of which 40 patients (17.3%) were divided into the handover period group, and 191 (82.6%) belonged to the non-handover period group. The results showed that the handover period group took significantly longer on items FMC2BS (P P Conclusion This study confirms that nursing handover impacts the nursing efficiency of STEMI patients, especially in FMC2BS and FMC2FAD. Hospitals should also reform the nursing handover rules after the construction of CPC and enhance the triage training of nurses to assure nursing efficiency so that CPC can play a better role.

In the ecosystem, microbiome widely exists in soil, animals, and plants. With the rapid development of computational biology, sequencing technology and omics analysis, the important role of soil beneficial microbial community is being revealed. In this review, we mainly summarized the roles of rhizosphere microbiome, revealing its complex and pervasive nature contributing to the largely invisible interaction with plants. The manipulated beneficial microorganisms function as an indirect layer of the plant immune system by acting as a barrier to pathogen invasion or inducing plant systemic resistance. Specifically, plant could change and recruit beneficial microbial communities through root-type-specific metabolic properties, and positively shape their rhizosphere microorganisms in response to pathogen invasion. Meanwhile, plants and beneficial microbes exhibit the abilities to avoid excessive immune responses for their reciprocal symbiosis. Substantial lines of evidence show pathogens might utilize secreting proteins/effectors to overcome the emerging peripheral barrier for their advantage in turn. Overall, beneficial microbial communities in rhizosphere are involved in plant–pathogen interactions, and its power and potential are being explored and explained with the aim to effectively increase plant growth and productivity.

The exploration of low-cost, stable, and highly active noble-metal-free electrocatalyst for hydrogen evolution reaction (HER) in a wide pH range is crucial but still challenging task for renewable energy techniques. MoS2-based materials have been considered as a promising electrocatalyst for HER. However, corresponding studies have been hampered by the lack of effective routes to fully utilize the large number of inert basal plane for catalyzing HER, especially under alkaline media. Herein, a novel ammonia ions-guided-nitrogenization-phosphorization strategy is developed to prepare N and P co-doped MoS2 with active basal plane for efficient catalyzing HER with a quite low overpotential of 116 and 78 mV in 0.5 M H2SO4 and 1.0 M KOH to achieve a current density of 10 mA cm−2, respectively. Experimental studies and theoretical calculations confirm Mo-N-P sites in the basal plane of MoS2 can not only accelerate HER kinetics, but also result in energetic favorability and structure stability. Furthermore, outstanding performances are also obtained under both sea and river water, vastly broadening the application prospects.

Burkholderia sp. JP2-270, a bacterium with a strong ability to inhibit the growth of Rhizoctonia solani, was isolated from the rhizosphere of rice. The phylogenetic analysis based on 16S rRNA gene revealed that JP2-270 belonged to Burkholderia cepacia complex. Here, we present the complete genome sequence of Burkholderia sp. JP2-270, which consists of three circular chromosomes (Chr1 3,723,585 bp, Chr2 3,274,969 bp, Chr3 1,483,367 bp) and two plasmids (Plas1 15,126 bp, Plas2 428,263 bp). A total of 8193 protein coding genes were predicted in the genome, including 67 tRNA genes, 18 rRNA genes and 4 ncRNA genes. In addition, mutation analysis of Burkholderia sp. JP2-270 revealed that the gene bysR (DM992_17470), encoding a lysR-type transcriptional regulator, was essential for the antagonistic activity of Burkholderia sp. JP2-270 against R. solani GD118 in vitro and in vivo. Identification of regulatory gene associated with antagonistic activity will contribute to understand the antagonistic mechanism of Burkholderia sp. JP2-270.

Both reactive oxygen species (ROS) and mitochondria are involved in many physiological and pathological processes. Herein, we employed curved corannulene with a large dipole moment for controlled ROS production and mitochondria targeting. Corannulene was solubilized in water via complexation with gamma-cyclodextrin (1 : 2). The complex could produce type I ROS in water in a dose- and irradiation time-dependent manner. The curvature-induced dipole moment aids electron transfer and hence enables ROS generation. As a consequence of electron delocalization, which facilitates mitochondrial uptake due to the large negative membrane potential of mitochondria, mitochondrial accumulation of corannulene was demonstrated. However, this is not valid for the flat perylene control. This discovery not only presents a new tool for controlled ROS production as well as mitochondria targeting in basic biomedical research, but also opens an avenue for the potential application of curved carbon materials as therapeutic agents.

The exploration of highly active and stable noble-metal-free electrocatalysts for hydrogen and oxygen evolution reaction is a challenging task to achieve sustainable production of H2 through water splitting. Herein, we present the design and synthesis of a novel three-dimensional(3D)-networked heterogeneous nickel phosphide/sulfide electrocatalyst consisting of Ni2P strongly coupled with Ni3S2 in situ grown on Ni foam. Benefiting from the strong interfacial coupling effects between Ni2P and Ni3S2, large surface area, highly conductive Ni foam support, and the unique 3D open configuration, the optimal 3D-networked hybrid electrode exhibits superior electrocatalytic activity with extremely low overpotentials of 80 and 210 mV to deliver a current density of 10 mA cm−2 for HER and OER in 1.0 M KOH, respectively. Assembled as an electrolyzer for overall water splitting, this electrode delivers an impressive low onset potential of only 1.45 V and gives a current density of 10 mA cm−2 at a very low cell voltage of 1.50 V, which is dramatically superior to the current state-of-the-art electrocatalysts. In combination with density functional theory (DFT) calculations, this study demonstrates that the strong coupling interactions between Ni2P and Ni3S2 synergistically optimize the electronic structure and tune the hydrogen (or water) adsorption energy, thus significantly enhancing the overall electrochemical water-splitting activity. Our work might shed some new lights on the design and fabrication of efficient and robust three-dimensional hybrid electrode materials for a variety of electrochemical applications.

Curved corannulene (Cor) can produce reactive oxygen species (ROS) in a controlled manner due to the large dipole moment. However, the poor aqueous solubility of Cor necessitates the employment of solubilization vehicles. This work revealed that PEGylation was less efficient than the cyclodextrin complexation regarding ROS production.

Due to the powerful anisotropy of the physical properties of volcanic reservoirs, their component minerals and pore configuration are very complex, rendering fluid identification very difficult. This paper first computed the cementation exponent, which was based on triple porosity model, then used the varied matrix density and matrix neutron to compute the porosity, and finally combined with resistivity well log, and a P1/2 probability distribution curve was built. The fluid properties were predicted from the shape of the P1/2 probability distribution curve. Good results were achieved when these methods were used in the volcanic reservoir of the Wangfu fault depression, which indicated that these methods can be used in the fluid property identification of volcanic reservoirs and can also be referred to for other lithology reservoirs.

The short-term prediction of EDH time series plays an exceedingly important role in several fields such as communications, navigation and so on. In this paper, an application of autoregressive integrated moving average (ARIMA) for short-term forecasting of EDH time series is presented. In order to obtain the EDH, a body of sensors such as air temperature, relative humidity and pressure sensors were installed at different height based on the tower platform. EDH was calculated according to Debye theory and a log-squares curve fit. The comparison showed that the predicted EDH values were in good agreement with the measured values. It also indicates that ARIMA provides promising results for short-term prediction of EDH in the experiment.

Rice (Oryza sativa L.) is a major cereal food crop worldwide, and its growth and yield are affected by several fungal phytopathogens, including Magnaporthe oryzae, Fusarium graminearum, F. moniliforme, and Rhizoctonia solani. In the present study, we have isolated and characterized root-associated bacterial endophytes that have antifungal activities against rice fungal phytopathogens. A total of 122 root-associated bacterial endophytes, belonging to six genera (Bacillus, Fictibacillus, Lysinibacillus, Paenibacillus, Cupriavidus, and Microbacterium) and 22 species were isolated from three rice cultivars. Furthermore, the 16S rRNA sequence-based phylogeny results revealed that Bacillus was the most dominant bacterial genera, and that there were 15 different species among the isolates. Moreover, 71 root-associated endophytes showed antagonistic effects against four major fungal phytopathogens, including M. oryzae, F. graminearum, F. moniliforme, and R. solani. Additionally, the biochemical, physiological, and PCR amplification results of the antibiotic-related genes further supported the endophytes as potential biocontrolling agents against the rice fungal pathogens. Consequently, the findings in this study suggested that the isolated bacterial endophytes might have beneficial roles in rice defense responses, including several bioactive compound syntheses. The outcomes of this study advocate the use of natural endophytes as an alternative strategy towards the rice resistance response.

Traditional low-rank representation (LRR)and variant algorithms based on LRR have been proved as effective methods for subspace clustering tasks in machine learning. However, the majority of the existing LRR-related algorithms relax the rank minimization problem by the trace norm minimization. It is rarely accurate to get the optimal solution guaranteed by the definition. Meanwhile, these methods can not well reveal the internal structure of the classification. In this paper, we propose an efficient and robust subspace clustering method to overcome these drawbacks. A robust self-representation coefficient matrix is learned by utilizing the Schatten- $p$ norm instead of the conventional rank function. Besides, the strongest block-diagonal structure of the coefficient representation matrix is enhanced by learning and optimizing the co-association matrix with the soft label of clustering results simultaneously in an unified framework. The affinity graphs constructed in this paper can clearly reveal the intrinsic structures of the data sets. Extensive experiments on the real data sets demonstrate that our novel proposed method can perform more effective than the state-of-the-art methods.

Shale content is known in reservoir evaluation as an important parameter in well logging. However, the log response characteristics are simultaneously affected by shale and tuff existing in tuffaceous sandstone reservoirs. Due to the fact that tuff content exerts an influence on the calculation of shale content, the former is equally important as the latter. Owing to the differences in the source and composition between shale and tuff, the calculation of tuff content using the same methods for shale content cannot meet the accuracy requirements of logging evaluation. The present study takes the tuffaceous reservoirs in the X depression of the Hailar–Tamtsag Basin as an example. The differences in the log response characteristics between shale and tuff are theoretically analyzed and verified using core analysis data. The tuff is then divided into fine- and coarse-grained fractions, according to the differences in the distribution of the radioactive elements, uranium, thorium and potassium. Next, a volume model suitable for tuffaceous sandstone reservoirs is established to include a sandstone matrix, shale, fine-grained tuff, coarse-grained tuff and pore. A comparison of three optimization algorithms shows that the particle swarm optimization (PSO) yields better calculation results with small mean errors. The resistivity differences among shale, fine-grained tuff and coarse-grained tuff are considered in the calculation of saturation. The water saturation of tuffaceous reservoirs is computed using the improved Poupon's equation, which is suitable for tuffaceous sandstone reservoirs with low water salinity. The method is used in well Y, and is shown to have a good application effect.

A polymeric micelle is a versatile nanoscale platform for sustained release of short-lived nitric oxide (NO). The aim of this work was to better understand the correlation between polymer architecture and NO release kinetics. Stable nitrate was selected as the NO donor and co-conjugated to a multivalent polymer backbone together with amphiphilic methoxy poly(ethylene glycol) and poly(lactic acid) (mPEG–PLA), or D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). Both graft polymers could self-assemble into micellar nanocarriers with a size less than 100 nm. The weight-based NO loading was 4.92% (w/w) and 6.05% (w/w) for mPEG–PLA- and TPGS-modified micelles, respectively. The former is less stable than the latter with a corresponding critical micelle concentration of 23.9 ± 2.0 nM and 9.8 ± 0.5 nM. Using the standard Griess assay, it was shown that both micelles could achieve sustained NO release in vitro. However, the TPGS-modified nanocarrier exhibited a delayed onset, but faster steady-state release of NO in comparison to its counterpart. This was primarily due to folded PEG conformation and its high packing surface density. These results illustrate the potential utility of polymer architecture engineering to precisely tune the NO release behavior for ultimately optimum therapeutic outcome.

The nonlinear effect of satellite's high power amplifiers causes the navigation signal distortion of limited bandwidth, which would affect signals in the power spectrum characteristic. This paper gave a signal model based on delay-multiplexing, improved fitting of nonlinear analyzing model (SAM model) on navigation signal. A new method of evaluating nonlinear distortion was presented, which was based on the signal in-band consisted of the effective signal and the jamming signal, and used the maximal effective output power as the evaluating characteristic. The influence of nonlinear distortion was simulated and analyzed on the fitting model in this paper. Further results showed that the delay-multiplexing be better than the direct-multiplexing in improving the effect of nonlinear distortion.

Temperature curves reflect geothermal gradients and local temperature anomalies, thus providing a new understanding of the underground reservoir conditions. When encountering caverns or fractures and fissures during drilling, lost circulation may occur and result in a change to the original formation temperature field, and in severe cases, even the conventional open hole well logging data cannot be obtained. This paper uses finite element analysis software COMSOL to establish a heat transfer model for the wellbore/reservoir formation system during drilling and shut-in in the presence of lost circulation, and a case study is made in a carbonate reservoir in the Tahe oilfield. On the basis of the above, we analyze the temperature distribution in the leakage zone, and the studies have shown that the leakage and petrophysical properties have an impact on the temperature of the wellbore and formation, hence we can estimate the reservoir permeability using the temperature data. In addition, the determination of the temperature recovery time after some drilling fluids have leaked into the formation will help in recognizing the subsurface temperature field of the carbonate formation correctly, thus enhancing production logging interpretation accuracy and improving the understanding of later measurements.

The rapid development of parks and ecotourism in China has attracted worldwide attention, not only for the beauty of the landscape that the parks are protecting but also for their abundant and often unique biodiversity. However, in some areas, the development of ecotourism has actually led to the degradation of local ecological, economic, and social systems. Using National Forest Parks for demonstration, this article analyzes the current political, institutional, legal, environmental, and economic issues concerning National Parks in China, and examines their potential future development. Although the intention of National Park systems in China is to raise environmental quality, and to protect biodiversity and social livelihoods, their success has varied. Future success will be measured by their capacity to reduce poverty, to promote long-term rehabilitation of wildlife habitats, and to simultaneously protect Chinese culture and biodiversity.

By adopting the Attitude System within the Appraisal System and the concepts of narrative roles and narrative points of view within narratology as the theoretical framework, the present study aims to analyze the distribution of attitudinal meanings, find out the similarities and differences of attitudinal meanings expressed by different narrative roles from different points of view and discuss how attitudinal meanings contribute to the analysis of the character depiction, plot development, theme presentation and the expression of irony in Emma.

In this paper, we propose a precorrelation direction lock loop (DiLL) scheme and a new modification factor estimation method for the global navigation satellite system (GNSS) receivers. The proposed scheme executes spatial correlation before code demodulator and does not need to do code demodulation for every antenna element. It can decrease the number of code demodulator to 3 regardless of the array element number while the postcorrelation DiLL scheme requires as many as array elements. Moreover, performance can be improved for immunity of undesired signals, multipath and interference, for example, from other different direction of arrivals compared with the postcorrelation DiLL scheme. The new modification factor estimation method is based on the prompt code branch and estimated angle outputs, which are suitable for reality environments. Theory analysis and simulation results show that two schemes are equivalent when the code tracking loop is working on the ideal tracking state under interference-free environment. The proposed scheme can also be used for DS/CDMA systems.

Although regulations limiting noise exposure in the workplace apply to individuals who wear communication headsets as part of their employment, no standard method for measuring this type of noise exposure has been available. A system for conducting this type of measurement has been developed. This system is indirect in that the electrical signal to the headset is measured after the transfer functions of the headset, ear, and a dosimeter microphone are applied to the signal. The resulting electrical signal is then inputted to a conventional dosimeter. While this approach requires that the transfer function of the headset be determined before a field measurement, it eliminates the need for a probe microphone in the wearer's ear. The transfer function of the headset (its effectiveness in generating sound) is measured using an acoustic manikin head. A significant number of headset brands and models have now been tested with this system in the laboratory, and the system is currently being used in the ...

Autonomous navigation is a significant element of satellite navigation systems. Current generation autonomous navigation of navigation satellite constellation typically employs the inter-satellites information only, which shows vulnerabilities due to the restriction of deficiencies and the on board processing units of inter-satellites links. In this paper, we describe an autonomous navigation of constellation method in virtue of satellite-ground links, along with aspects of the operating mode of autonomous navigation and the autonomous navigation of constellation with the aid of satellite-ground links. The proposed method is tested by simulations, proving its effectiveness for the precision improvement of autonomous navigation of constellation.

Signal waveform is an important factor to the navigation system such as tracking precision, anti-jamming and anti-multipath. Prolate Spheroidal Wave Functions (PSWF) are widely used in Ultra Wide Band (UWB) communication area. They are complete orthogonal set in the time domain that maximizes energy in the specified bandwidth. This paper presents PSWF bases method and orthogonal decomposition of waveforms. By optimizing coefficients, we can obtain optimum waveforms to minimize target functions with constrains. It presents a new method for waveform design of the navigation signals.