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Aims: Investigations into the nutrient content and changes in the stoichiometry and nutrient resorption strategies of different original forests during their development are of great significance toward the establishment of healthy, high-quality forest ecosystems. Methods: 24 sample plots with age gradients were established in natural Larix principis-rupprechtii forests and plantations, from which mature and senescent leaves, new branches, fine roots, and soil were collected for analysis. The carbon (C), nitrogen (N), and phosphorus (P) contents were determined, and the stoichiometric ratios and resorption efficiencies were calculated. Results and Conclusions: The soil organic carbon and total nitrogen of the forests accumulated with advancing age, while the total phosphorus decreased due to higher consumption. Plantation trees tended to store scarce nutrients within inactive plant structures to prevent nutrient loss, whereas natural forest trees maintained a stable nutrient concentration within their active organs. Plantation and natural forest trees adopted highly conservative N and P utilization strategies through improved resorption efficiencies. However, natural forest change was weaker than in plantations. The mature leaves, litter, branches, and fine roots of natural forestswere more susceptible to soil P concentrations, whereas those of their plantation counterparts were more affected by soil N. Nutrient concentrations within the active organs of plantation trees were more strongly dependent on soil than natural forests. We considered that natural forests likely possessed a more extensive range of strategies to deal with the variable compositions and concentrations of soil nutrients, which might strengthen their resilience against the effects of aging.

The effect of high-altitude (HA) on venous thromboembolism (VTE) and its mechanism remains ambiguous. To clarify this, we aimed to conduct a meta-analysis and systematic review to evaluate the incidence of VTE at HA and comparatively low altitude (LA) and figure out the intrinsic risk factors such as susceptibility genes of patients with VTE at HA.We selected studies that explored the risk factors for HA and VTE by searching PubMed, Embase, and Web of Science to analyze the impact of HA on VTE. All relevant studies before August 2021 were screened using the terms ([high altitude] OR [plateau] OR [mountain]) AND ([venous thromboembolism] OR [deep vein thrombosis] OR [pulmonary embolism]). Latest studies on the gene of HA-VTE patients were also summarized and analyzed.Fifteen studies were eventually assessed, and the overall numbers of subjects with and without VTE were 1475 and 286,926 respectively. The overall incidence of VTE, deep vein thrombosis (DVT) and pulmonary embolism (PE) in the HA group was significantly higher than that in the LA group (P0.01). The overall incidence of VTE, DVT and PE in the HA group was significantly higher than that in the LA group at 30 days post operation (P0.05, P0.05 and P0.01, respectively). At 90 days post operation, incidence of VTE and PE in the HA group was higher than that in the LA group (P0.01and P0.01, respectively), but there was no difference in the incidence of DVT (P = 0.07). Regarding endogenous factors, the analysis of genes in patients with HA-VTE revealed numerous targeted genes such as ANG, ACE, lncRNA-LINC00 659/UXT-AS1 and GP4.We observed a significant association between HA and the overall incidence of VTE and that at 30/90 days post operation, indicating that HA may be a risk factor for VTE.

The use of induction motor (IM) is a promising way to replace conventional mechanical actuation such as PMSM in small-size servo press. However, in order to achieve a better dynamical and steady performance than traditional control method, new control strategies have to be investigated. In this paper, model predictive control (MPC) of IM with Computed torque is implemented for the first time which can satisfy the strict positioning requirements in servo press. Additionally, PD control based on velocity and acceleration is employed. Simulation for algorithm is established on a servo press model and shows an improved performance with respect to the existing control strategies.

In order to improve the accuracy of trajectory planning, servo-drive of induction machine was employed in press. The crank mechanism is widely used as the critical transmission of the press. Dynamic model of press was established through Lagrange Equation and computed torque control method was chosen to solve the nonlinearity problem. To delivering better dynamic performance and reduce the cost of encoder, a predictive torque control of induction machine with an adaptive observer is also proposed in this scheme. The simulation shows the new algorithm can help servo-drive track the trajectory of crank and the performance of new strategy is better than traditional method. It can extent the new possible solution of trajectory for nonlinearity.

We read the paper by Rapado-Gonzalez et al. [1] with interest. The authors performed a large meta-analysis to evaluate the diagnostic value of salivary biomarkers for detection of malignant non-ora...

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is a negative regulator of T cell activation, which competes with CD28 for B7.1/B7.2 binding with a greater affinity. Co-expression specific antigens and extracellular domain of CTLA4 represents a promising approach to increase the immunogenicity of DNA vaccines. In this study, we evaluated this interesting approach for its enhancement on G250/MN/CA IX (G250)-specific immune responses and its anti-tumor effects in renal carcinoma mice model. Consequently, we constructed a DNA vaccine containing the G250 and the CTLA-4 gene. Vaccination with the co-expression DNA not only induced much higher level of anti-CTLA4 and anti-G250 antibody, but also increased G250-specific T cell response in mice. To evaluate the anti-tumor efficacy of the plasmids, murine models with G250-expressing tumors were generated. After injection into the tumor-bearing mouse model, the plasmid carrying the co-expression gene of CTLA4 and G250 showed stronger inhibition of tumor growth than the plasmid expressing CTLA4 or G250 alone. These observations emphasize the potential of the CTLA4 and G250 co-expression DNA vaccine, which could represent a promising approach for tumor immunotherapy.

Servo presses require accurate and fast response of driving torque from electric machines. To achieve higher metal forming performance, a model predictive control (MPC) algorithm has been implemented in the electric driver for current control in the presented study. Simulations and experiments have been carried out with MPC controller while proportional-integral (PI) controller of field oriented control (FOC) was used as comparison. The experiments have shown that MPC can produce fast and accurate current response, which leads to satisfactory trajectory following performances of major crank. It can be concluded that MPC is a solid alternative of traditional PI controller for motor drive of servo presses.

Average grain size is usually used to describe a polycrystalline medium, however, many investigations demonstrate the grain-size distribution has a measurable effect on most of mechanical properties. This paper addresses the experimental quantification for the effects of grain-size distribution on attenuation in &alpha, titanium alloy by laser ultrasonics. Microstructures with different mean grain sizes of 26&ndash, 49 &mu, m are obtained via annealing at 800 &deg, C for different holding times, having an approximately log-normal distribution of grain sizes. Experimental measurements were examined by using two different theoretical models: (i) the classical Rokhlin&rsquo, s model considering a single mean grain size, and (ii) the improved Turner&rsquo, s model incorporating a log-normal distribution of grain sizes in the attenuation evaluation. Quantitative agreement between the experiment and the latter model was found in the Rayleigh and the Rayleigh-to-stochastic transition regions. A larger attenuation level was exhibited than the classical theoretical prediction considering a single mean grain size, and the frequency dependence of attenuation reduced from a classical fourth power to an approximately second power due to a greater probability of large grains than the assumed Poisson statistics. The provided results would help support the use of laser ultrasound technology for the non-destructive evaluation of grain size distribution in polycrystalline materials.

This study aimed to identify the differential expression levels of androgen receptor (AR), estrogen receptors (ERα, ERβ), and progesterone receptor (PGR) between normal prostate and benign prostatic hyperplasia (BPH). The combination of immunohistochemistry, quantitative real-time reverse transcription polymerase chain reaction, and Western blotting assay was used to identify the distribution and differential expression of these receptors at the immunoactive biomarker, transcriptional, and protein levels between 5 normal human prostate tissues and 40 BPH tissues. The results were then validated in a rat model of BPH induced by testosterone propionate and estradiol benzoate. In both human and rat prostate tissues, AR was localized mainly to epithelial and stromal cell nuclei; ERα was distributed mainly to stromal cells, but not exclusively; ERβ was interspersed in the basal layer of epithelium, but sporadically in epithelial and stromal cells; PGR was expressed abundantly in cytoplasm of epithelial and stromal cells. There were decreased expression of ERα and increased expression of PGR, but no difference in the expression of ERβ in the BPH compared to the normal prostate of both human and rat. Increased expression of AR in the BPH compared to the normal prostate of human was observed, however, the expression of AR in the rat prostate tissue was decreased. This study identified the activation of AR and PGR and repression of ERα in BPH, which indicate a promoting role of AR and PGR and an inhibitory role of ERα in the pathogenesis of BPH.

A series of Pt nanoparticles supported on carbon nanotubes (CNTs) were synthesized using the incipient-wetness impregnation method. These catalysts were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscope (TEM) techniques. The characterization results indicate that the Pt nanoparticles were highly dispersed on the surface of the CNTs, and the mean size was less than 5 nm. These catalysts were utilized to convert cellulose to hexitol, ethylene glycerol (EG), and 1,2-propylene glycol (1,2-PG) under low H2 pressure. The total yields were as high as 71.4% for EG and 1,2-PG using 1Pt/CNTs as the catalyst in the hydrolytic hydrogenation of cellulose under mild reaction conditions.

This paper introduces a novel nondestructive testing (NDT) method based on laser ultrasonic technology and fiber Bragg grating (FBG) sensors. A FBG sensor is employed as discrete sensing elements to detect the ultrasonic generated by pulsed laser. An all-fiber and adaptive acousto-ultrasonic (AU) monitoring system for the dynamic detection of impact damage is developed for the present work. A tunable distributed feedback semiconductor laser is used to track AU frequencies as a demodulation scheme. To continuously lock the laser wavelength to the middle-reflection wavelength of FBG, a proportional-integral-derivative (PID) device is integrated with the signals from the photodetector in a feedback loop, thus stabilizing the operating points against quasi-state perturbations such as temperature and vibration, while the high frequency dynamic strain shifts the FBG reflection spectral profiles. We demonstrate the all-fiber adaptive AU demodulating system that has the sensing capability to monitor the high frequency AU signals using FBG that is glued on a loaded aluminum plate.

To observe the effects of different loading doses of atorvastatin calcium on the outcomes of percutaneous coronary intervention (PCI) in elderly patients with coronary heart disease (CHD).A total of 120 CHD patients aged over 80 years were randomly assigned into 3 equal groups to receive intensive pretreatment with statin at the doses of 20, 40, or 60 mg prior to PCI performed within 48 to 72 h after admission. The changes of postoperative cardiac biochemical markers including creatine kinase isoenzyme (CKMB), troponin I (cTNI) and high-sensitivity c-reactive protein (hs-CRP) were observed and the incidence of major adverse cardiac events (MACE, including cardiac death, myocardial infarction, and target vessel revascularization) were recorded within 30 days after PCI.Thirty-four patients in 20 mg statin group, 40 in 40 mg statin group, and 38 in 60 mg statin group completed this study. In all the 3 groups, hs-CRP level significantly increased at 12 and 24 h after PCI compared with the preoperative levels (P0.05). The patients in 60 mg statin group showed significantly lower levels of CKMB, cTNI, and hs-CRP at 24 h after PCI than those in 20 mg statin group (P0.05), and had also a significantly lower incidence of total MACE within 30 days after PCI (2.6% vs 26.5%, P=0.003) resulting primarily from significantly reduced myocardial infarction associated with PCI (2.6% vs 20.6%, P=0.016). The adverse drug reactions were comparable among the 3 groups (P0.05).Intensive pretreatment with 60 mg/day atorvastatin calcium can significantly reduce myocardial infarction related to PCI with good safety in elderly patients with CHD.