From an EtOAc-soluble extract of the roots of Taxus wallichiana, six new (1–6) and 11 known lignans were isolated. The structures of the new compounds were elucidated based on interpretation of ...spectroscopic data. (+)-7′-epi-Tsugacetal (1) is a rare aryltetralin-type lignan having a cis-orientation of H-7′ and H-8′. Compounds 3–6 were identified as the first naturally occurring tetrahydrofuranoid lignans having a cis-orientation of H-7 and H-8. All tested compounds were found to possess α-glucosidase inhibitory activity, with formosanol (9) showing the most potent effect with an IC50 value of 35.3 μM.
New structural, petrographic, and 40Ar/39Ar data constrain the kinematics of the ASRR (Ailao Shan‐Red River shear zone). In the XueLong Shan (XLS), geochronological data reveal Triassic, Early ...Tertiary, and Oligo‐Miocene thermal events. The latter event (33–26 Ma) corresponds to cooling during left‐lateral shear. In the FanSiPan (FSP) range, thrusting of the SaPa nappe, linked to left‐lateral deformation, and cooling of the FSP granite occurred at ≈35 Ma. Rapid cooling resumed at 25–29 Ma as a result of uplift within the transtensive ASRR. In the DayNuiConVoi (DNCV), foliation trends NW‐SE, but is deflected near large‐scale shear planes. Stretching lineation is nearly horizontal. On steep foliations, shear criteria indicate left‐lateral shear sense. Zones with flatter foliations show compatible shear senses. Petrographic data indicate decompression from ≈6.5 kbar during left‐lateral shear (temperatures >700°C). 40Ar/39Ar data imply rapid cooling from above 350°C to below 150°C between 25 and 22 Ma without diachronism along strike. Along the whole ASRR cooling histories show two main episodes: (1) rapid cooling from peak metamorphism during left‐lateral shear; (2) rapid cooling from greenschist conditions during right‐lateral reactivation of the ASRR. In the NW part of the ASRR (XLS, Diancang Shan), we link rapid cooling 1 to local denudations in a transpressive environment. In the SW part (Ailao Shan and DNCV), cooling 1 resulted from regional denudation by zipper‐like tectonics in a transtensive regime. The induced cooling diachronism observed in the Ailao Shan suggests left‐lateral rates of 4 to 5 cm/yr from 27 Ma until ≈17 Ma. DNCV rocks always stayed in a transtensive regime and do not show cooling diachronism. The similarities of deformation kinematics along the ASRR and in the South China Sea confirms the causal link between continental strike‐slip faulting and marginal basin opening.
The radiological complications including correction loss and hardware failure of short segment posterior pedicle screw fixation in the treatment of unstable thoracolumbar burst fractures remain a ...main concern. Several procedures aiming to reinforce the anterior column have been introduced to solve these limitations, including transforaminal interbody fusion (TIF). The purposes of this study were to evaluate the radiological complications of short-segment pedicle screw fixation in combination with transforaminal interbody fusion in the treatment of unstable thoracolumbar burst fractures.
This retrospective case series study enrolled patients with isolated unstable thoracolumbar burst fractures, who were treated by posterior short fixation with TIF between January 2013 and January 2017. Patients were followed up for a minimum of one and half years. For evaluation of correction loss, % loss of anterior vertebral body height (%AVB), vertebral kyphotic angle (VA) and regional kyphotic angle (RA) were collected preoperatively, postoperatively and at the final follow-up. Hardware failure was assessed on radiological images at the last follow-up.
There were 36 patients who met the inclusion criteria with a mean follow-up duration of 53 months. The mean correction loss of %AVB, VA and RA were 10.2%, 2.9
and 5.6
, respectively. There were 6 patients (16.7%) with hardware failure at the final follow-up.
Short-segment posterior pedicle screw fixation with TIF using bone chip grafts does not completely prevent hardware failure and progressive kyphosis in the treatment of unstable thoracolumbar burst fractures.
Improving the quality of life (QOL) of people living with diabetes is the ultimate goal of diabetes care. This study provides a quantitative overview of global research on interventions aiming to ...improve QOL among people with diabetes. A total of 700 English peer-reviewed papers published during 1990-2018 were collected and extracted from the Web of Science databases. Latent Dirichlet Allocation (LDA) analysis was undertaken to categorize papers by topic or theme. Results showed an increase in interventions to improve the QOL of patients with diabetes across the time period, with major contributions from high-income countries. Community- and family-based interventions, including those focused on lifestyle and utilizing digital technologies, were common approaches. Interventions that addressed comorbidities in people with diabetes also increased. Our findings emphasize the necessity of translating the evidence from clinical interventions to community interventions. In addition, they underline the importance of developing collaborative research between developed and developing countries.
Among other fields, climate change has a great influence on metal corrosion that reduces the durability and reliability of steel structures. A time-dependent reliability analysis includes ...time-dependent climate scenarios and deterioration processes as well as random variables, material properties, and dimensions. The extent of corrosion damage is calculated by tracking the evolution of the corrosion process using Monte Carlo simulations. The current paper presents a time-dependent reliability assessment of a continuous I-shaped steel beam, considering the corrosion effects of climate change in Vietnam. The results showed that the safety probability of a continuous steel beam considering metal corrosion from the pristine to 100 years reduces from 96.77% to 63.08%. These findings can be used to assess and provide a cost-technical analysis of climate adaptation measures.
Introduction: Postoperative surgical site infection remains one of the major complications after spinal surgery. IntraSPINER (intraspine) is a dynamic intralaminar device introduced by Cousin Biotech ...and is indicated for the surgical treatment of lumbar spine disorders. There are no reports on delayed surgical site infection (SSI) after lumbar surgery using this device. Case Presentation: A 29-year-old male patient was admitted to our department with complaints of moderate pain and chronic subcutaneous abscess with purulent flow from his old surgical scar. Thirty-four months ago, he underwent a traditional open bilateral L4 laminotomy without discectomy and intraspine insertion for the treatment of L4-5 central lumbar spinal stenosis at another hospital. The patient was discharged 4 days after surgery without radiating pain, and the surgical wound was well healed. He gradually returned to his normal activity and work. However, he experienced moderate pain, redness and swelling of his old surgical scar approximately one month before coming to our hospital, but he did not receive any treatment. One month later, he had a mass with purulent discharge at the surgical scar site, and he visited our hospital on December 29th, 2020. Based on the physical examination and MRI findings, delayed-SSI was diagnosed. The patient underwent removal of the intraspine device, debridement and wound closure with closed drainage. The wound healed satisfactorily, and the patient had no complaints more than 2 years later. Conclusion: A delayed surgical site infection following intraspine insertion may have occurred. Keywords: postoperative surgical infection, artificial device, lumbar disc herniation
This paper proposes a method for determining location and calculating the minimum amount of power load needed to shed in order to recover the frequency back to the allowable range. Based on the ...consideration of the primary control of the turbine governor and the reserve power of the generators for secondary control, the minimum amount of load shedding was calculated in order to recover the frequency of the power system. Computation and analysis of the voltage electrical distance between the outage generator and the loads to prioritize distribution of the amount power load shedding at load bus positions. The nearer the load bus from the outage generator is, the higher the amount of load shedding will shed and vice versa. With this technique, a large amount of load shedding could be avoided, hence, saved from economic losses, and customer service interruption. The effectiveness of the proposed method tested on the IEEE 37 bus 9 generators power system standard has demonstrated the effectiveness of this method.
This paper proposes a method of load ranking and load shedding in a power system based on the calculation of the priority weighting continuity of the power supply of loads and the improved AHP ...algorithm. The proposed method applies the theories of covariance between objects, correlation, and fuzzy preference to develop a fuzzy preference correlation matrix based on the percentage of Vital Load, Semi Vital Load, and Non-Vital Load at each load bus. This matrix replaces the judgment matrix of the traditional AHP algorithm to form the criteria layers and scheme layers of the problem. The priority weighting continuity of the power supply of loads is continuously calculated and updated according to the load profile and is used to distribute the load shedding power to each load bus. This distribution optimizes the objective function and maximizes the load benefits, thereby minimizing the damages due to load shedding. The traditional AHP method and the proposed method are applied to the IEEE 30 bus system and the result comparison demonstrates the effectiveness of the proposed method.
Abstract
Forest ecosystems are part of the vital and indispensable resources for human survival and social development. Forests not only provide materials such as wood and firewood for some ...industries, but also maintain and protect the environment, such as climate regulation, erosion control and sedimentation, water regulation and flood mitigation. However, due to some uncontrolled activities of people and abnormal natural conditions, forest fires occur more frequently and severely. U Minh Ha National Park (UMHNP) is one of forest which has the highest risk of forest fires in the Mekong Delta. This study was conducted to assess the status of forest fires and the impacts of climate change on forest fire risk in UMHNP then proposed appropriate measures to reduce the risk of forest fire to minimize damage to the environment, humans, biodiversity, economics as well as people’s livelihoods protection in the Mekong Delta. By the method of data collection and rapid assessment, the topic has statistics of fires within 5 years as well as causes, key areas and its impacts on forest ecosystems. At the same time, it was pointed out that UMHNP is facing an increasing risk of forest fire due to climate change. Forest fire prevention and fighting in UMHNP is being well implemented but still faces some difficulties. Therefore, it is necessary to take appropriate measures such as strengthening communication, completing mechanisms and policies, supplementing fire protection equipment and facilities to improve environmental quality and local’s people life.
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