Search

Large components are crucial in modern industrial applications, especially for internal gap monitoring and specific assembly methods. This paper examines the assembly of hydroelectric generator rotors and stators, introducing a spatial relative position monitoring system using multiple sensors. A dedicated position monitoring program is designed, and error sources within the system are thoroughly explored. Detailed error analysis and modeling reveal that verticality and angular errors significantly impact monitoring accuracy. To address this, two error control methods are proposed to effectively mitigate these issues, ensuring precise assembly of large components. [ABSTRACT FROM AUTHOR]

The minimum resolvable temperature difference (MRTD) at which a four-rod target can be resolved is a critical parameter used to assess the comprehensive performance of thermal imaging systems, which is important for technological innovation in military and other fields. Recently, there have been some attempts to use an automatic objective approach based on deep learning to take the place of the classical manual subjective MRTD measurement approach, which is strongly affected by the psychological subjective factors of the experimenter and is limited in accuracy and speed. However, the scale variability of four-rod targets and the low pixels of infrared thermal cameras have turned out to be a challenging problem for automatic MRTD measurement. We propose a multiscale deblurred feature extraction network (MDF-Net), a backbone based on a yolov5 neural network, in an attempt to solve the aforementioned problem. We first present a global attention mechanism (GAM) attention module to represent strong images of the four-rod targets. Next, a Rep VGG module is introduced to decrease the blur. Our experiments show that the proposed method achieves the desired effect and state-of-the-art detection results, which innovatively improve the accuracy of four-rod target detection to 82.3% and thus make it possible for the thermal imagers to see further and to respond faster and more accurately. [ABSTRACT FROM AUTHOR]

(1) Background: Anesthetic sedatives are widely used for bronchoscopy, and controversy surrounds the safety and efficacy of dexmedetomidine compared to other sedatives. The aim of this study is to evaluate the safety and efficacy of dexmedetomidine in bronchoscopy through a systematic review. (2) Methods: PubMed, Embase, Google Scholar, and Cochrane Library electronic databases were searched for a randomized controlled study of dexmedetomidine (Group D) or other sedative drugs (Group C) for bronchoscopy. Data extraction, quality assessment, and risk of bias analysis were performed in accordance with the preferred reporting items for systematic review and meta-analysis requirements. Meta-analysis was performed using RevMan 5.2. (3) Results: Nine studies were included, with a total of 765 cases. Compared to Group C, the incidence of hypoxemia (OR = 0.40, 95% CI (0.25, 0.64) p = 0.0001, I2 = 8%) and tachycardia (OR = 0.44, 95% CI (0.26,0.74), p = 0.002, I2 = 14%) were lower, but bradycardia (OR = 3.71, 95% CI (1.84, 7.47), p = 0.0002, I2 = 0%) was higher in Group D; no significant difference was observed in other outcome indicators. (4) Conclusions: Dexmedetomidine reduces the incidence of hypoxemia and tachycardia during bronchoscopy but is more likely to provoke bradycardia. [ABSTRACT FROM AUTHOR]

In this paper, a new six dimensional memristor chaotic system is designed by combining the chaotic system with a memristor. By analyzing the phase diagram of the chaotic attractors, eleven different attractors are found, including a multi-wing attractor and symmetric attractors. By analyzing the equilibrium point of the system, it is proven that the system has the property of a hidden chaotic attractor. The dynamic behavior of the system when the three parameters change is analyzed by means of LEs and a Bifurcation diagram. Other phenomenon, such as chaos degradation, coexistence of multiple attractors and bias boosting, are also found. Finally, the simulation on the DSP platform also verifies the accuracy of the chaotic system simulation. The theoretical analysis and simulation results show that the system has rich dynamical characteristics; therefore, it is suitable for secure communication and image encryption and other fields. [ABSTRACT FROM AUTHOR]

Surrogate models are commonly used in place of computationally expensive simulations in engineering design and optimization, and the predictive performance of surrogate models is usually influenced by the quality of design of experiments (DoE). One way to eliminate the effect of the randomness of DoE is to average multiple prediction accuracies over multiple DoEs. However, how many DoEs are needed to obtain stable prediction results for problems with different dimensionalities remains a challenging issue. Mathematical test functions have been employed in a large body of literatures to identify the predictive performance of surrogate models. In this work, 30 test functions ranging from 1 dimension to 16 dimensions are selected to investigate the relationship between the number of DoEs needed for a stable prediction accuracy and the number of sample points. A convergence condition is used to determine whether a reliable model accuracy has been obtained. In this paper, the number of DoEs required for estimating the model accuracy is provided as a suggestion for those who develop surrogate models and select test functions to validate the performance of models. [ABSTRACT FROM AUTHOR]

Disturbance by small burrowing herbivores often has an impact on plant aboveground biomass of grassland because it makes grasslands into a mosaic of discrete vegetated surfaces and bare soil patches. This study focuses on the plateau pika (Ochotona curzoniae) to investigate the effect of the disturbance by a small burrowing herbivore on plant aboveground biomass through upscaling the quadrat scale to the plot scale across five sites. This study showed that the plateau pika disturbance reduced sedge biomass and increased forb biomass. In contrast, they did not affect plant community biomass, grass biomass and legume biomass at the quadrat scale across the five sites. At the plot scale, that is, when the bare soil patches with a lack of plants were considered, plateau pika disturbance induced lower aboveground biomass of the plant community, sedge and legumes, while it had no relationship with grass biomass and forb biomass. As the disturbance intensity increased, the aboveground biomass of the plant community and sedge decreased, whereas the grass biomass showed a hump-shaped trend. These results indicate that plateau pika disturbance might be not beneficial to alpine meadows given the aboveground biomass of the plant community at the plot scale. In contrast, the intermediate disturbance intensity improves the grazing quality of alpine meadows through the higher grass biomass. The findings of this study imply that the plot scale is better than the quadrat scale to investigate the influence of the disturbance by a small burrowing herbivore on the plant aboveground biomass, and that management of a small burrowing herbivore needs to consider its disturbance intensity. [ABSTRACT FROM AUTHOR]

Salt stress severely threatens the growth and productivity of Glycyrrhiza uralensis. Previous results found that Bacillus cereus G2 enhanced several carbohydrate contents in G. uralensis under salt stress. Here, we analyzed the changes in parameters related to growth, photosynthesis, carbohydrate transformation, and the glycolysis Embden-Meyerhof-Parnas (EMP) pathway-tricarboxylic acid (TCA) cycle by G2 in G. uralensis under salt stress. Results showed that G2 helped G. uralensis -accumulating photosynthetic pigments during photosynthesis, which could further increase starch, sucrose, and fructose contents during carbohydrate transformation. Specifically, increased soluble starch synthase (SSS) activity caused to higher starch content, which could induce α-amylase (AM) and β-amylase (BM) activities; increased sucrose content due to the increase of sucrose synthase (SS) activity through upregulating the gene-encoding SS, which decreased cell osmotic potential, and consequently, induced invertase and gene-encoding α-glucosidase that decomposed sucrose to fructose, ultimately avoided further water loss; increased fructose content-required highly hexokinase (HK) activity to phosphorylate in G. uralensis , thereby providing sufficient substrate for EMP. However, G2 decreased phosphofructokinase (PFK) and pyruvate kinase (PK) activities during EMP. For inducing the TCA cycle to produce more energy, G2 increased PDH activity that enhanced CA content, which further increased isocitrate dehydrogenase (ICDH) activity and provided intermediate products for the G. uralensis TCA cycle under salt stress. In sum, G2 could improve photosynthetic efficiency and carbohydrate transformation to enhance carbohydrate products, thereby releasing more chemical energy stored in carbohydrates through the EMP pathway-TCA cycle, finally maintain normal life activities, and promote the growth of G. uralensis under salt stress. [ABSTRACT FROM AUTHOR]

Support vector regression (SVR) has been widely used to reduce the high computational cost of computer simulation. SVR assumes the input parameters have equal sample sizes, but unequal sample sizes are often encountered in engineering practices. To solve this issue, a new prediction approach based on SVR, namely as high-low level SVR approach (HL-SVR) is proposed for data modeling of input parameters of unequal sample sizes in this paper. The proposed approach consists of low-level SVR models for the input parameters of larger sample sizes and high-level SVR model for the input parameters of smaller sample sizes. For each training point of the input parameters of smaller sample sizes, one low-level SVR model is built based on its corresponding input parameters of larger sample sizes and their responses of interest. The high-level SVR model is built based on the obtained responses from the low-level SVR models and the input parameters of smaller sample sizes. A number of numerical examples are used to validate the performance of HL-SVR. The experimental results indicate that HL-SVR can produce more accurate prediction results than SVR. The proposed approach is applied to the stress analysis of dental implant, in which the structural parameters have massive samples but the material of implant can only be selected from Ti and its alloys. The obtained prediction results of the HL-SVR approach are much better than SVR. The proposed approach can be used for the design, optimization, and analysis of engineering systems with input parameters of unequal sample sizes. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a risk stratification index (RSI) system to guide intensive care unit (ICU) resource use for elderly patients after hip fracture surgery. The authors' first study cohort consisted of 302 elderly patients with hip fractures who had surgical treatment at their hospital. The authors conducted multivariate logistic regression analysis to investigate relevant risk factors for ICU resource utilization postoperatively. An RSI system was developed based on the significant risk factors from regression analysis. A second study cohort consisted of 205 elderly patients, among whom the authors applied the RSI system to guide ICU resource assignment. Among the first cohort of 302 hip fracture patients, 89 were transferred to ICU postoperatively, of whom 81 were planned to be transferred to ICU and 8 were not. Multivariate stepwise regression analysis revealed that age (≥80 years), preoperative pulmonary disease, perioperative anemia (hemoglobin <8 g/dL), and perioperative lactic acid level (>2 mmol/L) were independent risk factors for postoperative ICU management. The authors then constructed a weighted RSI with these risk factors. In addition, they manually added American Society of Anesthesiologists classification (III/IV) and types of anesthesia as additional risk factors based on their clinical experience. It was determined that an RSI score greater than 4 required postoperative ICU care. The RSI system was then prospectively applied to an independent cohort of 205 elderly surgical patients with hip fractures, among whom only 40 required ICU care. More importantly, there were no later transfers from the general ward to ICU after the application of RSI. The RSI system is effective for guiding postoperative ICU transfer without compromising patient care and minimizes unexpected transfers from the general ward to the postoperative ICU. [Orthopedics. 2020;43(3):e159-e165.]. [ABSTRACT FROM AUTHOR]

Introduction: Low serum albumin is associated with higher perioperative complications following total hip arthroplasty (THA). The distinct threshold for a significant rise in perioperative complications has not been defined for THA. The purpose of this study was to define the threshold at which perioperative complications rise after THA. Methods: We analysed the American College of Surgeons NSQIP database from 2006 to 2013. Our study cohort included unilateral primary THA with reported preoperative albumin levels. Patients were stratified by albumin level. We analysed mortality and 6 composite complication variables (any complication, any complication without transfusion, wound infection, systemic infection, cardiac/pulmonary complications, and any major complication). All data analysis was executed in STATA statistical software. Multivariable logistic regression analysis was used to adjust for odds ratios. Results: The final cohort included 24,586 patients who were stratified based upon serum albumin levels. Odds ratios after multivariable regression adjustment for age, gender, race, body mass index, ASA classification, and Charlson Comorbidity Index indicated a trend to elevated odds of complication for all composite complications (3 of which were statistically significant) when serum albumin level was <3.0 g/dL. Conclusion: Low serum albumin is associated with increased perioperative complications following THA. The threshold associated with an increase in major perioperative complications appears to be an albumin level of <3.0 g/dL. With attempts to correct modifiable risk factors prior to surgery, the threshold value at which perioperative complications increase is important to define. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the incidence, related risk factors, and outcomes of postoperative delirium (POD) in severely burned patients undergoing early escharotomy. This study included 385 severely burned patients (injured <1 week; TBSA, 31-50% or 11-20%; American Society of Anesthesiologists physical status, II-IV) aged 18 to 65 years, who underwent early escharotomy between October 2014 and December 2015, and were selected by cluster sampling. The authors excluded patients with preoperative delirium or diagnosed dementia, depression, or cognitive dysfunction. Preoperative, perioperative, intraoperative, and postoperative information, such as demographic characteristics, vital signs, and health history were collected. The Confusion Assessment Method was used once daily for 5 days after surgery to identify POD. Stepwise binary logistic regression analysis was used to identify the risk factors for POD, t-tests, and χ tests were performed to compare the outcomes of patients with and without the condition. Fifty-six (14.55%) of the patients in the sample were diagnosed with POD. Stepwise binary logistic regression showed that the significant risk factors for POD in severely burned patients undergoing early escharotomy were advanced age (>50 years old), a history of alcohol consumption (>3/week), high American Society of Anesthesiologists classification (III or IV), time between injury and surgery (>2 days), number of previous escharotomies (>2), combined intravenous and inhalation anesthesia, no bispectral index applied, long duration surgery (>180 min), and intraoperative hypotension (mean arterial pressure < 55 mm Hg). On the basis of the different odds ratios, the authors established a weighted model. When the score of a patient's weighted odds ratios is more than 6, the incidence of POD increased significantly (P < .05). When the score of a patient's weighted odds ratios is more than 6, the incidence of POD increased significantly (P < .05). Further, POD was associated with more postoperative complications, including hepatic and renal function impairment and hypernatremia, as well as prolonged hospitalization, increased medical costs, and higher mortality. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibetan Plateau is a very large land unit and an important terrestrial ecosystem within the Eurasian continent. Because of the harsh climate associated with the high altitude, alpine meadows on the plateau are susceptible to degradation from overgrazing. For this region, and for other alpine meadow pastures internationally, there is a need to define the sustainable stocking rate, to develop sound policy pertaining to future land use. Here we report biomass and liveweight gain per animal and per ha for pastures grazed by yaks at high, medium, or low stocking rates over 4 growing seasons from 2010 to 2013. Measures of herbage nutritive value are reported. The influence of inter-year variation in precipitation on standing herbage biomass was also evaluated. Higher precipitation increased standing herbage biomass and herbage nutritive value, indicating that vegetation suffered summer water deficit even in this environment. The sustainable stocking rate in this environment was determined to be approximately 1 yak ha-1 (grown from 80 kg to 120 kg liveweight in 90 d). At this stocking rate, yak weight gain per ha was 88% of that achieved at higher stocking rates typically used by farmers, but with little or no evidence of land degradation. [ABSTRACT FROM AUTHOR]

The Moderate Resolution Imaging Spectroradiometer (MODIS)/Terra daily snow cover product MOD10A1 was compared with in situ climate station measurements and a snow map generated from Landsat Enhanced Thematic Mapper Plus (ETM+) data. Snow-covered area (SCA) dynamics were assessed using the MODIS 8-day snow cover composite product MOD10A2 for the 2001-2005 snow seasons in northern Xinjiang, China. The results indicate that the snow-mapping agreement between MODIS daily snow maps and surface observations is high at 94.6% over the four snow seasons under clear-sky conditions. The snow classification accuracy in a mountainous area was lower than that in a plain area and caused higher omission errors, probably resulting in an underestimation of the SCA. The omission errors were mainly determined by snow depth, land cover types, the terrain and mixed pixels. The cloud agreement was 95.9%, and approximately 4.1% of cloud was misclassified as snow when the sky view at the climate stations was covered by clouds. An improvement was found in suppressing clouds using the 8-day products, with MOD10A2 reducing about 88.4% of the average cloud cover compared with MOD10A1. SCA in northern Xinjiang retrieved using MOD10A2 shows a clear seasonal trend. The air temperature plays an important role in the fractional SCA, and the spatial distribution of the snow cover differs considerably in the various areas in the northern Xinjiang region. [ABSTRACT FROM AUTHOR]

Monitoring and estimating potential snow disasters in pastoral areas of northern Xinjiang Province are important for decision-making in hazard reduction and prevention. In this paper, four scenes of NOAA/AVHHR (Advanced Very high Resolution Radiometer) images were combined with ground observation data in the north of Xinjiang Province to establish a model for monitoring snow depth. Using a linear spectral decomposition method, the pixel-based snow coverage and snow classification were studied. The spatial characteristics of snow, grassland, animal and climate factors were used to develop two new quantified indices for estimating the potential snow hazard grade and for integrated evaluation of snow disasters to grassland animal husbandry. The criteria for snow hazard grade and snow disaster evaluation were established. Results indicated that: (i) a pixel-based index K1, based on grassland yield, animal capacity, utilisable grassland area coefficient and seasonal grazing utilisation scenarios, can be quantitatively integrated to reflect the grassland capability of resisting snow disasters; (ii) the snow hazard index (K) systematically expresses the spatial and temporal changes of grassland and snow cover, and analyses, and predicts and evaluates the snow hazard grade under conditions where climatic and animal husbandry information may be unavailable during snow disasters. This index plays an important role in studies on early warning of snow hazard in pastoral areas; (iii) the integrated snow disaster evaluation index (E) and related classification criteria reflect the details of snow disaster magnitude in temporal and spatial scales, which provide the basic information for dynamic monitoring and integrated evaluation on snow disasters in pastoral areas. [ABSTRACT FROM AUTHOR]

When population abundances exceed the economical or ecological threshold, animals are always regarded as pests, so effective and sustainable management strategies are required. As a native species widely distributed on Tibetan Plateau, plateau pika is regarded as a pest when its abundance is too high. For decades, plateau pika were controlled using toxic baits by both the local government and shepherds. However, how pika population fluctuates after lethal control is far from certain. Based on our previous studies, demographic parameters of plateau pika were acquired. A system dynamics model is developed to parameterize a population model for this species. The model incorporates two age categories (juvenile and adult) of both sexes, and uses density-dependent factors, including reproduction, mortality, and migration. The model is used originally to analyze the effect of pika management on the population dynamics and resulting abundance, in order to plan optimal pest controlling strategies. The results show that lethal control is efficient when continuously conducted once each year, or twice with 2-year intervals. For sustainable controlling pest abundance, comprehensive strategies should be considered. An appropriate population model could be used to explore the optimal strategies and provide important reference into decision making about pest management. [ABSTRACT FROM AUTHOR]

Abstract: The fault diagnosis of rolling element bearing is important for improving mechanical system reliability and performance. When localized fault occurs in a bearing, the periodic impulsive feature of the vibration signal appears in time domain, and the corresponding bearing characteristic frequencies (BCFs) emerge in frequency domain. However, in the early stage of bearing failures, the BCFs contain very little energy and are often overwhelmed by noise and higher-level macro-structural vibrations, an effective signal processing method would be necessary to remove such corrupting noise and interference. In this paper, a new hybrid method based on optimal Morlet wavelet filter and autocorrelation enhancement is presented. First, to eliminate the frequency associated with interferential vibrations, the vibration signal is filtered with a band-pass filter determined by a Morlet wavelet whose parameters are optimized by genetic algorithm. Then, to further reduce the residual in-band noise and highlight the periodic impulsive feature, an autocorrelation enhancement algorithm is applied to the filtered signal. In the enhanced autocorrelation envelope power spectrum, only several single spectrum lines would be left, which is very simple for operator to identify the bearing fault type. Moreover, the proposed method can be conducted in an almost automatic way. The results obtained from simulated and practical experiments prove that the proposed method is very effective for bearing faults diagnosis. [Copyright &y& Elsevier]

Background: While survival rates among cardiac allograft recipients have improved, there has been a rise in post-transplant malignancies, with gastric cancer being less commonly reported. This study presented a successful treatment of gastric cancer in an individual 10 years after undergoing a heart transplant., Case Presentation: A 66-year-old Chinese man presented to the gastrointestinal clinic with a complaint of diagnosis of gastric cancer for 4 months and treated with neoadjuvant therapy for 1 month. He has undergone orthotopic heart transplantation 10 years earlier due to a myocardial infarction. Physical examination and laboratory tests did not reveal any significant abnormalities. Abdominal contrast-enhanced computed tomography (CT) imaging indicated a gastric mass near the greater curvature, with gastroscopy suggesting a carcinoma at the esophagogastric junction, Siewert III. An echocardiogram indicated left atrial enlargement with mild mitral and tricuspid regurgitation. The diagnosis suggested that his gastric cancer at the esophagogastric junction was a consequence of long-term immunosuppressive therapy. A multidisciplinary team (MDT) consultation recommended a proximal radical gastrectomy. Postoperatively, the patient received 4 cycles of adjuvant chemotherapy with XELOX combined with Herceptin, initiated a month after surgery. During the 1-year follow-up, the patient showed commendable recovery, with no signs of tumor recurrence or metastasis., Conclusion: This case underscores the potential risk of malignancy from immunosuppressive agents in transplant recipients. The successful management of this complex scenario underscores the indispensable role of an MDT approach in treating such unique and challenging cases., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: The problem of achieving economic efficiency in sheep breeding can be largely solved by increasing sheep productivity. Recently, the BMPRIB gene has been revealed by GWAS as a potential candidate gene for sheep body morphometric traits. Therefore, the present study aimed to investigate whether genetic polymorphisms (p.Q249R SNP and 90-bp deletion) in the BMPRIB gene are associated with sheep growth traits., Methods: PCR-based genotyping was performed on 1,875 sheep, including 1,191 Guiqian semi-fine wool (GQSFW), 560 Luxi Blackhead (LXBH), 55 Lanzhou fat-tailed (LZFT), and 69 Weining (WN) sheep. Genotype-phenotype association was assessed using the independent samples t -test and ANOVA. The significance level was set at α original < 0.05. The threshold p -value for significance was adjusted after correction for multiple comparisons using the Bonferroni correction., Results: After the Bonferroni correction, it was found that individuals with FecB + /FecB + genotypes of the p.Q249R had significantly better growth traits in LXBH ewe lambs, including the body length, chest width, paunch girth, cannon circumference, and hip width ( P <0.0005). Meanwhile, associations were observed between 90-bp deletion polymorphism and several growth traits (body length, body height, chest depth, and canon circumference) in GQSFW ewe adults after the Bonferroni correction ( P < 0.0002), and individuals with the "DD" genotypes had greater growth traits., Conclusion: Our findings align with the experimental observations from GWAS, which identified the BMPRIB gene as a potential candidate gene for body measurement traits. These findings not only confirm the previous study's results but also expand on them. Therefore, further investigations regarding the impact of BMPRIB polymorphisms on growth traits are necessary in other sheep breeds., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xu, Akhmet, Luo, Guo, Pan, Song, Malmakov, Akhatayeva and Lan.)

Background: Intrathecal analgesia (ITA) is a valuable treatment option for refractory cancer-related pain. However, there is still no general consensus on the analgesic effect of movement-evoked breakthrough pain (MEBTP) in the ITA setting., Objectives: This study aimed to conduct a retrospective observational study to examine the effect of ITA via percutaneous port (ITAPP) with patient-controlled ITA (PCIA) on analgesic efficacy, emphasizing MEBTP in patients with refractory lower extremity cancer pain., Study Design: A retrospective chart review included all patients with refractory lower extremity cancer pain who received ITAPP at our hospital between January 2017 and December 2020., Methods: Data on the Numeric Rating Scale scores of spontaneous resting pain intensity (SRPI) and MEBTP intensity (MEPI), opioid doses, and perceived time to onset were collected from medical records prior to ITAPP and at a one-month postimplant visit., Results: A total of 16 patients were included in the study group. Mean SRPI decreased from 8.75 pre-ITAPP to 3.75 post-ITAPP (P < 0.05); mean MEPI fell from 8.83 pre-ITAPP to 4.25 post-ITAPP (P < 0.05); mean daily morphine equivalent dosing decreased from 360 mg/d to 48 mg/d (P < 0.05); and mean daily morphine equivalent dosing for MEBTP decreased from 87 mg/d to 6 mg/d (P < 0.05). Both total and breakthrough dosing of conventional opioid medications significantly decreased following the initiation of ITAPP with PCIA. The mean perceived time to onset with conventional MEBT medications was 38 minutes, and the mean perceived time to onset with PCIA was 8 minutes (P < 0.05)., Limitations: An effective analysis of IT opioid efficacy was not possible because the power of such a small sample size was low. Second, it is a retrospective study without long-term follow-ups., Conclusions: In patients with refractory lower extremity cancer pain, ITAPP with PCIA was associated with improved pain control. Compared with conventional MEBTP regimens, appropriate ITAPP with PCIA provided superior analgesia and a much faster onset of action.

Background: Evidence-based international expert consensus regarding the impact of peripheral nerve block (PNB) use in total hip/knee arthroplasty surgery., Methods: A systematic review and meta-analysis: randomized controlled and observational studies investigating the impact of PNB utilization on major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, thromboembolic, neurologic, infectious, and bleeding complications.Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, were queried from 1946 to August 4, 2020.The Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess evidence quality and for the development of recommendations., Results: Analysis of 122 studies revealed that PNB use (compared with no use) was associated with lower ORs for (OR with 95% CIs) for numerous complications (total hip and knee arthroplasties (THA/TKA), respectively): cognitive dysfunction (OR 0.30, 95% CI 0.17 to 0.53/OR 0.52, 95% CI 0.34 to 0.80), respiratory failure (OR 0.36, 95% CI 0.17 to 0.74/OR 0.37, 95% CI 0.18 to 0.75), cardiac complications (OR 0.84, 95% CI 0.76 to 0.93/OR 0.83, 95% CI 0.79 to 0.86), surgical site infections (OR 0.55 95% CI 0.47 to 0.64/OR 0.86 95% CI 0.80 to 0.91), thromboembolism (OR 0.74, 95% CI 0.58 to 0.96/OR 0.90, 95% CI 0.84 to 0.96) and blood transfusion (OR 0.84, 95% CI 0.83 to 0.86/OR 0.91, 95% CI 0.90 to 0.92)., Conclusions: Based on the current body of evidence, the consensus group recommends PNB use in THA/TKA for improved outcomes., Recommendation: PNB use is recommended for patients undergoing THA and TKA except when contraindications preclude their use. Furthermore, the alignment of provider skills and practice location resources needs to be ensured. Evidence level: moderate; recommendation: strong., Competing Interests: Competing interests: SGM is a director on the boards of the American Society of Regional Anesthesia and Pain Medicine (ASRA) and the Society of Anesthesia and Sleep Medicine (SASM). He is a one-time consultant for Sandoz and the holder of US Patent Multicatheter Infusion System. US-2017-0361063. He is the owner of SGM Consulting, LLC and Centauros Healthcare Analytics and Consulting. SGM is also a shareholder in Parvizi Surgical Innovations LLC and HATH. None of the above relations influenced the conduct of the present project., (© American Society of Regional Anesthesia & Pain Medicine 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Common chemotherapeutic agents such as oxaliplatin often cause neuropathic pain during cancer treatment in patients. Such neuropathic pain is difficult to treat and responds poorly to common analgesics, which represents a challenging clinical issue. Corydalis yanhusuo is an old traditional Chinese medicine with demonstrated analgesic efficacy in humans. However, the potential analgesic effect of its active component, levo-tetrahydropalmatine (l-THP), has not been reported in conditions of neuropathic pain. This study found that l-THP (1-4 mg/kg, i.p.) produced a dose-dependent anti-hyperalgesic effect in a mouse model of chemotherapeutic agent oxaliplatin-induced neuropathic pain. In addition, we found that the anti-hyperalgesic effect of l-THP was significantly blocked by a dopamine D1 receptor antagonist SCH23390 (0.02 mg/kg), suggesting a dopamine D1 receptor mechanism. In contrast, l-THP did not significantly alter the general locomotor activity in mice at the dose that produced significant anti-hyperalgesic action. In summary, this study reported that l-THP possesses robust analgesic efficacy in mice with neuropathic pain and may be a useful analgesic in the management of neuropathic pain.

With disturbed and undisturbed belts during the construction of Qinghai-Tibet highway as test objectives, this paper studied the effects of human engineering activities on the permafrost ecosystem in northern Qinghai-Tibetan plateau. The results showed that the thickness of permafrost active layer was smaller in disturbed than in undisturbed belt, and decreased with increasing altitude in undisturbed belt while no definite pattern was observed in disturbed belt. Different vegetation types had different effects on the thickness of permafrost active layer, being decreased in the order of steppe > shrub > meadow. In the two belts, altitude was the main factor affecting the vertical distribution of soil moisture, but vegetation type was also an important affecting factor if the altitude was similar. Due to the human engineering activities, soil temperature in summer was lower in disturbed than in undisturbed belt.

It is of significance to establish an integrated evaluation system of snow disaster in northern pastoral areas. Based on the NOAA satellite digital images, field observation data, and maps of grassland type and seasonal pastureland, this paper selected the winter and spring pasturelands in Aletai region of Xinjiang as the main area of snow disaster-remote sensing monitoring. With affecting factors of economy and the characteristics of natural resource distribution comprehensively analyzed, and using 3S techniques and field survey information, a fundamental information processing model for integrated evaluation of snow disaster was built up, and snow disaster-spatial evaluation indices and damage level systems were constructed. Natural and social systems and 20 indices were selected in snow disaster evaluation indicator system. Four principal factors, i.e., snow cover area, snow depth on grassland, persistence days of low temperature, and livestock death rate, were used as the grading indices of snow disaster damage level, and the models of snow disaster identification and loss estimatation were set up to quantitatively analyze snow disaster. The results indicated that the system could accurately reflect the details of snow hazard grade and the situation of a disaster in temporal and spatial scales, which would help to carry out the dynamic monitoring and scientific estimatation of big area's snow disaster in pastoral region.

Grassland degradation, an important problem in grassland management, has affected the sustainable development of animal husbandry in Alatai region of Xinjiang. Based on the analysis of the community features, ecological service value and multiple functions, and main function of grassland types in the regional development, the classified management for grassland was designed. The results showed that Alatai grassland could be divided into three sectors, i.e., ecological function region, economic function region and mixed function region. The ecological function region made up 164.66 x 10(4) hm2 or 16.73% of total Alatai grassland, and the grassland types included alpine meadow, alpine rangeland, swamp, mountain desert steppe, mountain steppe desert and part of plain desert. For the ecological function region, the main management strategy was to prohibit grazing and cropping. The economic function region of 116.33 x 10(4) hm2 accounted for 11.82% of the total Alatai grassland, the grassland types included mountain meadow, flat meadow and meadow steppe, and the main management strategy to enhance the productivity was agricultural measures, such as fertilization and irrigation. The mixed function region which included mountain steppe, plain desert steppe and most part of plain desert was 703.21 x 10(4) hm2 or 71.45% of total Alatai grassland, and the main management strategy was rotational grazing.

Based on the theories of sustainable development of forest resources, this paper constructed an index system for the integrative evaluation on the sustainability of forest resources in Bailon River forest region of Gansu Province. After calculated the index values of five strategic levels and twenty measure levels, the degree of harmony (DH) was obtained, with which, the sustainability of test forest resources could be evaluated. The DH value was 0.5320 in 1996 and 0.6100 in 2000, which was smaller than the theoretic value of 0.7000, and hence, this forest region belonged to non-sustainable development, but made some progress for its sustainability.

A field study was conducted in the hilly and valley regions of Loess Plateau in Gansu Province to analyze the root system development ability of several alfalfa (Medicago sativa) cultivars. Eight introduced cultivars and one local cultivar were arranged in the same site. The secondary roots of alfalfa cultivars grew mainly from the taproot underground 10-20 cm depth, and there were no secondary roots below 50 cm depth. The total amount of secondary roots of Sandili and Ameristand 201 was the biggest, and that of Longdong alfalfa was the lowest. The volume and biomass of different cultivars were decreased from 0-10 cm depth to below 50 cm depth, except those of Sandili and Ameristand 201 at 20-30 cm depth was bigger than at 10-20 cm depth. The biomass of Ameristand 201 was 170.54 g and bigger than that of others, and that of Longdong alfalfa, which was 22.4% of Ameristand 201, was the lowest. According to cluster analysis on 9 alfalfa cultivars, Sandili, Ameristand 201 and Amerigraze 401 were suitable for planting on the hills and valleys of Loess Plateau due to their root system development ability.

The dynamics of forage supply and nutrition requirements of sheep were monitored for a whole year under alpine grassland conditions in Sunan County, Gansu Province. The digestion and metabolism of grazed sheep were determined in different seasons. The results showed that the DE(9.76 MJ), CP(21.53%) and the ratio of crude protein to digestible energy (22.06 g.MJ-1) of forage were the highest in Spring, while the herbage dry matter yield and dry matter intake (60.51 +/- 3.42 g.W0.75kg-1.d-1) by grazed sheep were the lowest. Supplementary DM especially in energy should be provided. The ratio of crude protein to digestible energy was 17.62 g.MJ-1 in Summer, and was somewhat higher. The nitrogen utility of the forage would be improved, if energy feed was supplemented. Both the quality and quantity of forage produced in grasslands in Autumn could meet the sheep requirement. Whereas during Winter, neither forage yield nor nutritive value was sufficient for sheep, and the contents of the DE and CP of forage were the lowest in the year, which were 4.30 MJ and 4.63%, respectively. The nitrogen metabolism of sheep was negative. Therefore, DM, especially DE and CP, should be supplemented. To improve the conditions, it was necessary to develop seasonal animal husbandry, and combine the subsystems into coupling systems.