bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on runoff variation trend and hydrological situation variation in Wujiang River Basin
Authors: Wei Guo , Jun Shao , Yangshuo Ou , Liqiang Yao , Guangdong Wu , Ning Cui Fu , Kun Wang
Published: August 2021

This paper selected the Wujiang River Basin as the study area, and restored the runoff process at Wulong station through complicated calculation. By using Mann-Kendall, Kendall rank correlation test and other test methods, there was no significant trend for the runoff in the Wujiang River Basin. The RVA method was applied to analyze the influence degree for the existing cascade reservoir operation on the hydrological regime of the Wujiang River, and it was concluded that the overall hydrologic indicators alteration degree of Wulong Station was high. By simulating the operation scenarios of the cascade reservoirs, future hydrological regime alteration of Wulong station was predicted. Compared with the current situation of Wulong station, the results showed that the inflow will decrease in flood season, and the inflow will increase in dry season.
Influence of mixed free-surface and pressurized flow on transients process in a tailrace tunnel of a tailrace surge chamber
Authors: Gaohui Li , tianchi Zhou , Fei Yang , Yimin Chen , wangjia Danzhen
Published: August 2021

In the calculation of hydraulic transients in a hydropower station, the hydraulic problems caused by free-surface and pressurized flow are relatively complex. In consideration of this phenomenon, numerical simulation is used in this paper to study the effect of the transient free-surface, pressurized flow in a tailrace tunnel on the minimum pressure at inlet of the draft tube and the lining segment of the tailrace tunnel and the effect on the primary frequency regulation of the unit. The results show that the existence of tailrace surge tank can reduce the disturbance of the mixture flow on the units. Meanwhile, free-surface and pressurized flow can speed up the attenuation of the surge in the surge tank. Reasonable arrangement can mitigate transients in the tailrace system, which may provide a reference for similar projects.
Research on flood forecast of dashimen reservoir in xinjiang based on melting snow and runoff yield under excess infiltration
Authors: Liu Yi , Zhang Fenglong , Wu Haiyan , Li Yongfeng , Jiang Zhiqiang , Li Qingqing , Wang Yan , Yi Tailai
Published: August 2021

In China, the distribution of water resources is uneven in time and space. The effective allocation of water resources can realize the rational utilization of water resources. Reservoirs are an important part of the basin system, and the rational operation of reservoirs can realize the optimal allocation of water resources. Flood forecast is of great significance for reservoir operation. In order to realize the optimal operation of Dashimen reservoir in Xinjiang, aiming at the flood forecast in the dry area affected by melting snow, this paper expanded and improved the traditional hydrological forecast model, built the flood forecast model in the dry area with the coupling snowmelt based on the northern Shaanxi model and Elman neural network, and using the typical rainfall and runoff data in this area The results show that the relative error of the model is less than 10% and the accuracy is high, which can be used in the actual forecast. This model realizes the flood forecast in the drought area affected by snowmelt, and provides a new idea for the flood forecast of reservoir in the drought area affected by snowmelt, which has a certain guiding significance for the flood forecast in the drought area.
Analysis and Research on the Influencing Factors of Sediment Discharge of Wanjiazhai Reservoir in 2018
Authors: Zhihui Ren , Ting Wang , Shaojun Qu , Zilu Wang , Huaibao Ma
Published: August 2021

Sediment discharge method has great impact on the service life and comprehensive benefits of the reservoirs in sediment-laden river. In this paper, the actual operation process of Wanjiazhai Reservoir in 2018 was taken as the research object to analyze changes in runoff and sediment process and erosion and deposition in the reservoir area, and to explore possible influencing factors for reservoir sediment discharge. According to the results, the erosion in the reservoir area of Wanjiazhai Reservoir in 2018 was 112.6 million t, the erosion period was concentrated in August and September, and the erosion positions were concentrated at the elevation of 935-966 m; the deposition morphology in the reservoir area changed obviously after twice sediment flushing in 2018, and the channel has been subject to deepening and widening accompanied by reservoir bank collapse; there is a negative correlation between the outflow sediment concentration/sediment discharge ratio of the reservoir and the reservoir water level.
Experimental and simulation studies on the attenuation coefficients of organic pollutants in “Han River and Three Tributaries” basin, China
Authors: Zheng Jing , Hao Chen , Huiqun Cao , Jian Tang , Rui Li
Published: August 2021

In order to study the attenuation mechanism and spatial and temporal evolution of organic pollutants in “Han River and Three Tributaries” basin, laboratory experiments were conducted, and a novel COD attenuation coefficient model was proposed. The main environmental factors affecting COD attenuation were identified. On this basis, the attenuation term of the one-dimensional water quality model is modified, and the spatial and temporal distribution characteristics of COD in Hanbei River are simulated and analyzed using the modified water quality model. The results show that: (1) the attenuation process of COD in Hanbei River is basically in accordance with the first-order reaction kinetics, and biodegradation accounts for a large proportion of the whole attenuation process. Within a certain range, the increase of flow velocity, water temperature and sand content promoted COD attenuation, and the effect of sediment particle size on COD attenuation in Hanbei River was not obvious; (2) based on the experimental results, a model for calculating the attenuation coefficient of pollutants is derived. A time varying attenuation coefficient can be calculated, which can realistically reflect the attenuation process and the distribution pattern along the river under the changing environment; (3) Model simulations determined that the COD attenuation coefficient of Hanbei River ranged from 0.03 to 0.19. The research results of this paper provide a scientific and theoretical method to accurately determine the attenuation coefficient of pollutants. It also provides scientific support for determining the ecological water demand of typical rivers and lakes similar to “Han River and Three Tributaries” and the scale of water diversion for Interconnected River System Network.
Research on the progress of urban lake water environment assessment
Authors: Xiaoyu Cui , Pengfei Zhang , Wenqi Peng , Huihuang Luo , yunxia Gao , Jinyong Zhao
Published: August 2021

Urban lake water environment management and water ecosystem restoration have always been research hotspots in China and abroad. However, there have always been different opinions on the water environment situation, water environment evaluation and subsequent water environment regulation of urban lakes worldwide. Based on the investigation of water environment in China and abroad, this research summarizes the main water quality evaluation methods of urban lakes, and systematically analyzes and organizes the main evaluation methods, in order to provide references for the future evaluation and restoration of urban lakes.
Preliminary Study on Ecological Water Conservancy Strategy to Cope with Climate Challenge
Authors: Xie Zundang , Lv Xiaolong , Chen Xingliang
Published: August 2021

Global warming has caused sea level rise, extreme meteorological events, flood and drought disasters. From the perspective of ecological civilization construction, taking China as a typical example, this paper explored how to deal with the adverse impact of climate change on human and ecosystem through the development of ecological water conservancy. The main measures were as follows: firstly, construct the national water network connecting the natural water systems in the South and North of China, play the role of the Yellow River as a link to ecologically replenish water in arid and semi-arid areas; secondly, recover the over exploited groundwater in North and Northeast China and the ancient lakes in Northwest China. By storing a large amount of water on land, the goal that slowing down the speed of the sea level rise, reducing the flood damage in the south and coastal areas, repairing and improving the ecological environment in the north and northwest regions of China and spurring the local economic development could be achieved.
Development of SOA-Based Hydrological Data Compilation Management System
Authors: Yang Yu , Dazhong Xia , Zheng Jin
Published: August 2021

As the results of hydrological data compilation are important fundamental information resources in China, how to efficiently manage them and provide data support for water science research is a major problem that needs to be addressed at present. In this paper, a hydrological database of Haihe River Basin was preliminarily established based on the compilation of the complete electronic data files, and a SOA-based management system of hydrological data compilation results was developed, featuring functions related to the compilation results. The research shows that the system boasts strong practicability and operability, and will be popularized in the later period, in order to improve the capacity and level of hydrological service, support water conservancy information and drive the modernization of hydrological service.
Analysis about the impacts of changing basin underlying surface on design floods for design units of water diversion projects
Authors: Minglei Ren , Xiaodi Fu , Liuqian Ding , Gang Wang , Guangyuan Kan , Liping Zhao , YaFeng Zhu
Published: August 2021

After the water diversion project has been put into operation for many years, due to the long distance, complex hydro-meteorological conditions, and rapid development of social economy, the underlying surface conditions of corresponding natural basins in the design units of water diversion project have changed to some extent compared with the beginning of the project design, especially the underlying surface situation of rivers in the northern region has changed greatly. Based on ArcGIS to extract basin characteristic values of the design unit of water diversion project, such as basin area, river length and slope, this paper analyzes the changes of current basin characteristic values of design unit compared with the design period. For the design unit with significant changes in the basin characteristics, the original design flood calculation method is used to calculate the flood of the same design rainstorm under current conditions, and the impacts of changing basin underlying surface on design floods are analyzed.

PACS: J0101
Study on preparation and strength of high-strength micro-expansive lightweight aggregate concrete
Authors: Huiqin Yao , dongmei Liu
Published: August 2021

Orthogonal design was used to research the effect of water cement ratio and the content of expansive agent and fiber on the compressive strength, bending strength and splitting strength of high-strength micro-expansive lightweight aggregate concrete. The optimum mixing proportion of lightweight concrete considering different strength target was determined through the integrated balance method. Results indicated that, the splitting strength and bending strength was about 0.04 times and 0.08∼0.12 times as big as the compressive strength when the intensity grade of lightweight concrete was LC45 or LC50. The content of ZY expansive agent has a notable influence on compressive strength, and has certain influence on bending strength. The water cement ratio and polypropylene fiber content have no significant effect on different strength target. The optimum mixing proportion for high-strength micro-expansive lightweight aggregate concrete was that, the content of ZY expansive agent and polypropylene fiber were respectively 8% and 0.1%, and water cement ratio was 0.30. The strength grade of LC50 for the optimum mixing proportion has been achieved.
Research on Treatment Technology of High Ammonia Nitrogen Wastewater from Shale Refinery
Authors: Yuting Fu , Changbo Li , Guozheng Zhao , Dongyu Li , Zikai Sun , Jiatong Yang
Published: August 2021

This article describes the nature and hazards of shale refining high ammonia nitrogen wastewater, and summarizes the characteristics of various treatment technologies for shale refining high ammonia nitrogen wastewater. Methods for treating ammonia-containing nitrogen include chemical precipitation and the like. This article reviews the research status and development trend of shale refining high-ammonia wastewater treatment technology.
Design of remote operation and maintenance platform of substation DC system for field defect handling
Authors: Li Wenwei , Wang Xiaoming , Shi Jun
Published: August 2021

The current remote operation and maintenance platform of substation DC system mainly relies on manual use of each independent monitoring device to collect and transmit data for remote operation and maintenance management, which is difficult to realize intelligent operation of substation and also leads to slow response and poor processing performance of operation and maintenance platform. In order to optimize the above-mentioned problems, the remote operation and maintenance platform of substation DC system for on-site defect processing is studied and designed. Based on the framework of the operation and maintenance platform, a combination of balanced and unbalanced bridge-based principle is used to monitor the DC insulation status. The JSON protocol is used to realize the data interaction between the operation and maintenance platform and the management terminals, and to design the DC system defect processing scheme. The Floyd shortest path algorithm is used to plan the operation and maintenance inspection strategy of the platform to achieve fast operation and maintenance of the DC system. The platform performance test results show that the performance index of the designed operation and maintenance platform is significantly improved, and the average request response time is shortened by 28.1%, and the operation and maintenance management effect is better.
Design and implementation of a simulation optimization method for high arch dams
Authors: Li Guo , Wu Jianming , Tan Yaosheng , Liu Chunfeng , Pei Lei , Song Liangfeng , Yu Hu
Published: August 2021

The construction scale of high arch dams is large and the overall structure is complex. Numerical simulation results obtained only by quoting standard parameters or laboratory measurements are quite different from actual engineering conditions. Based on a set of temperature-stress coupling simulation system, the key thermodynamic parameters used in the simulation calculation are further optimized through monitoring data and experimental results, so as to be close to the actual engineering state and better for studying the working status of high arch dams. Combined with actual applications, it is shown that the optimized results of the method are consistent with the actual objective laws, can better reflect the real situation, reduce the “noise” interference in the data, and verify the correctness and feasibility of the method.
Concrete life prediction model based on freeze-thaw damage theory and its application
Authors: Yang Dongpeng , Guo Weimin , Wang Baomin
Published: August 2021

For hydraulic concrete structure in cold and severe cold areas in northern China, its frost resistance directly restricts the life and safe and stable operation of the project. In this paper. Based on the freeze-thaw damage theory, this paper optimizes and improves the Weibull distribution model, and uses the 1:1:4 standard frost-resistant specimen of hydraulic concrete as the physical model to obtain a freeze-thaw damage model that is more in line with the standard specimens of the rapid freeze-thaw experiment. Based on this model, a concrete life prediction method is proposed. In order to solve the problem that the initial damage of coring concrete is not clear, an iterative approximation method is proposed. The life prediction method proposed was verified through actual engineering cases. The results show that the model can better describe the process of concrete freeze-thaw damage and destruction, and the life prediction results are more reliable.
Numerical Simulation of Connected Flow in the Inlet and Outlet of the Pumping Storage Power Station
Authors: Li Gaohui , Wu Xumin , Yao Minjie , Liu Ning , wangjia DanZhen , Cui WeiJie
Published: August 2021

Pumping and storage power stations with different hydraulic units are simultaneously in power generation and pumping operation (same-in-one pumping operation) is an effective means to alleviate the adverse effects caused by the sudden power imbalance of the power grid and adapt to the emergency dispatching requirements of the power grid. In this mode of operation, the water flow in the different inlet and outlet ports is reversed, and water flow communication will be formed in the front pool. Aiming at the problem that the connected flow is difficult to measure in physical model test and prototype observation, a three-dimensional flow field numerical simulation is used to determine the flow connection path and orifice velocity distribution, and the area-weighted average method is used to obtain the connected flow calculation method for different paths. Taking the inlet and outlet of a pumped storage power station as an example, this method is used to analyze the flow rate of the orifice and its proportion. The results show that when the pumped storage power station is running in the same pumping operation, the flow rate of some orifices will exceed 80% of its total flow. It is easy to cause the cooling water of the unit to circulate between the hydraulic units and keep heating up, thus reducing the cooling effect of the unit.
Finite element analysis of stress in the gallery of gravity dam on inclined bedrock based on ANSYS model
Authors: Gao Shang , Chen Yan , Xiang Junhong
Published: August 2021

Taking a variety of galleries in a concrete gravity dam body as the research object, it analyzes the changing law of stress concentration phenomenon around the galleries in the dam body affected by the holes of the galleries. Use the large-scale finite element application software ANSYS to model the dam and the bedrock within a limited range, change the position of the gallery to obtain different solid models, and obtain the stress distribution map around the gallery after loading calculations. The results show that when the distance between the gallery and the upstream dam surface changes from 3.0 to 9.0m, the maximum principal stress of the gallery section gradually decreases and tends to remain unchanged; there is obvious stress concentration at the gallery and the dam heel. When the drainage gallery is arranged in the vertical direction, the change of the distance affects the stress distribution and state of the gallery. When the distance is changed from 15 to 25m, the stress changes from 0.106e7 to 0.088e7Pa, and tends to be stable, and the mutual influence gradually decreases. This provides guidance and suggestions for the design of the gravity dam gallery on the inclined bedrock.
Analysis on Evolution Characteristics of Hydrometeors in South China Based on Lagrange Tracking Method
Authors: Song Wenting , Li Yunying , Ye Chengzhi
Published: August 2021

To reveal the microphysical process of clouds inside a rain cluster and identify the causes of changes in water resources in the air in South China, rain cluster areas with the radar reflectivity factor higher than 40dBZ in a heavy precipitation process in South China were defined as convective cloud cores, and areas with the factor greater than 20dBZ and less than 40dBZ as stratiform clouds around cores with Lagrange tracking method based on S-band dual-polarization radar data. An analysis was conducted on the evolution law of the types of hydrometeor particles and variation characteristics of the raindrop size spectrum in the two areas as well as their differences. The results showed that convective cloud cores and surrounding stratiform clouds were composed of large and sparse raindrops at the early stage of development; the particle crushing process mainly occurred inside stratiform clouds at the mature stage, and the collision-coalescence process mainly occurred at the attenuation stage. Stratiform clouds showed a process of increase in the density of graupel particles at the stage of precipitation enhancement, but the density of graupel particles in convective cores did not change significantly; high- and low-density graupel particles in convective cores had a higher frequency of occurrence than those in stratiform clouds.
Review on carbon capture technology of Oxy-fuel combustion in coal fired boiler
Authors: Tu Anqi , Zhang Zhiyong , Gao Zhengping
Published: August 2021

In China, the total amount of energy resources is huge, the types are rich, but the per capita share is small, the resource structure is unreasonable, and the distribution space is uneven. Compared with the global average level, China’s energy mineral resources richness is about 60% higher, which is one of the countries with higher global energy mineral resources richness [1]. However, China’s per capita share of energy resources is very limited, only half of the world level, and the structure of energy resources is unreasonable. The proportion of oil and gas is only 2.3%, far from the world average of 21%. Therefore, carbon capture and storage technology is the most effective way to reduce carbon dioxide (CO2) emission of coal fired on a large scale, and can reduce the CO2 emission of coal fired by more than 90%. This paper reviews the most promising carbon capture technology of the Oxy-fuel combustion in coal fired boiler.
Application of electric meter in the smart distribution network
Authors: Feili Yang , Ke Zheng , Yingying Cheng , Xun Guo , Yuting Zhang
Published: August 2021

The purpose is to promote equipment automation in the smart distribution network and improve the electricity detection accuracy and reliability of power equipment. Here, electric meters in the smart distribution network are studied. Firstly, the current electricity detection methods are discussed. Secondly, the common electric meter fault mechanisms are summarized and analyzed. Finally, the GM (Grey Mole) (1,1) is optimized through ACO (Ant Colony Optimization) algorithm and is used for detection and investigation of the real-time electric meter monitoring system. Then, simulation experiments are conducted based on the user’s electricity consumption data. The results indicate that the load correction value optimized by the ACO algorithm is closer to the actual load than the predicted value, and the absolute residual value is greatly reduced compared with the predicted value. At the same time, the prediction trend is more similar. This shows that the ACO-optimized GM can effectively improve the accuracy of the electric meter monitoring system.
Analysis on Management Strategy of Lightning Protection in Hunan Distribution Lines
Authors: Li Jin-liang , Zhao Miao , Chen Xiao-rong , Zhou Heng-yi , Sun Ze-zhong , Peng Si-min , Tao Jie , Tang Wen
Published: August 2021

The lightning activity is frequent in Hunan, and frequent lightning activities seriously affect the safe and stable operation of distribution network equipment. The statistical analysis of lightning trip-out in Hunan distribution line is made in this paper. According to the current situation of lightning protection in Hunan distribution lines, the differentiated lightning protection management strategy is proposed, which takes into account the ground flash density and special landform factors. And the field application in the past year shows that the effect of lightning protection is good. However, there are also corresponding management and technical problems in the implementation process. The corresponding solution ideas and suggestions are put forward in this paper based on the fully investigation and the experimentation simulation, which has the certain reference value for further improving the lightning withstand level of hunan distribution lines.
Accurate investment evaluation model of power grid based on Improved Fuzzy Neural Inference
Authors: Liu Kunpeng , Gong Lihua , Tian Nuo , Liu Bo , Liu Lili
Published: August 2021

In the accurate investment evaluation of power grid, the existing model does not consider the uncertainty of the actual evaluation object, and the evaluation subject mainly relies on subjective judgment, resulting in low information utilization rate. Therefore, the accurate investment evaluation model of power grid is designed based on Improved Fuzzy Neural Inference. The evaluation index system is established from three aspects of power supply capacity, power supply quality and power grid benefit of power grid investment, so as to achieve the purpose of giving consideration to both economic and social benefits. Based on the Improved Fuzzy Neural Inference, the membership function algorithm is designed, and the parameters are adjusted to obtain the best fuzzy inference results. According to the membership function and index improvement value, the standardized data table is established. The indicators of the same level are quantified, and the weight attributes are solved to complete the construction of accurate investment evaluation model of power grid. The experimental results show that the design model has certain advantages in the utilization rate of investment information, which is 10.59%, 15.40% and 9.95% higher than the existing models. It proves that the accurate investment evaluation model of power grid constructed in this paper is closer to the actual situation and has good application effect.
Study on Association Rules Based on Multiple Types of Flexible Loads
Authors: Jiang Feng , Cai Zhuang , Zhang Kai , Zhan Keming , Gu Bo
Published: August 2021

At present, the comprehensive consideration of multiple types of flexible loads and the complementary characteristics in time and space are less considered, which results in the user’s response potential cannot be further explored. This paper takes flexible load as the research object, and proposes a method for the research of association rules based on multiple types of flexible loads. An association rule mining and evaluation model is established to form an intelligent offline database and a relative connection degree database. As a result, the correlation of various types of flexible loads is discovered through the cooperation of the two, so as to provide guidance for dispatching.
Effect of stretching on the orientation structure and reaction behavior of PAN fiber during the thermal stabilization
Authors: Wang Bin , Li Chenggao , Cao Weiyu
Published: August 2021

The evolution of structures and properties of Polyacrylonitrile (PAN) precursor fiber during the thermal stabilization was directly related to the mechanical properties of carbon fiber. In the present study, the effects of stretching on the orientation structure and reaction behavior of PAN fibers at different thermal stabilization stages were experimentally investigated. The multi-dimensional structural characterization and mechanical properties tests were used, such as XRD, FT-IR, 13C-NMR, Raman and material testing machine, etc, which would help to reveal the evolution mechanism of the microstructure and reaction behavior of PAN fiber during the thermal stabilization. The results showed that in the process of thermal stabilization, stretching caused the rearrangement of crystalline orientation structure, promoted the cyclization reaction process at higher temperature (>200 °C), and furthermore promoted the formation of oriented aromatic like lamellar structure. It can be found that when the drawing ratio of 10% and the exposed temperature at 200 °C were applied to the PAN fiber, the increasing of crystalline orientation was obvious and more aromatic lamellar structures generated. Based on the above process technology, the carbon fiber with the higher graphitization degree and better mechanical properties was finally obtained.
The topological Dirac equation of networks and simplicial complexes
Authors: Bianconi Ginestra
Published: August 2021

We define the topological Dirac equation describing the evolution of a topological wave function on networks or on simplicial complexes. On networks, the topological wave function describes the dynamics of topological signals or cochains, i.e. dynamical signals defined both on nodes and on links. On simplicial complexes the wave function is also defined on higher-dimensional simplices. Therefore the topological wave function satisfies a relaxed condition of locality as it acquires the same value along simplices of dimension larger than zero. The topological Dirac equation defines eigenstates whose dispersion relation is determined by the spectral properties of the Dirac operator defined on networks and generalized network structures including simplicial complexes and multiplex networks. On simplicial complexes the Dirac equation leads to multiple energy bands. On multiplex networks the topological Dirac equation can be generalized to distinguish between different mutlilinks leading to a natural definition of rotations of the topological spinor. The topological Dirac equation is here initially formulated on a spatial network or simplicial complex for describing the evolution of the topological wave function in continuous time. This framework is also extended to treat the topological Dirac equation on 1 + d lattices describing a discrete space-time with one temporal dimension and d spatial dimensions with d ∈ {1, 2, 3}. It is found that in this framework space-like and time-like links are only distinguished by the choice of the directional Dirac operator and are otherwise structurally indistinguishable. This work includes also the discussion of numerical results obtained by implementing the topological Dirac equation on simplicial complex models and on real simple and multiplex network data.
Facial Aging Surgery: Healing Time, Duration Over the Years, and the Right Time to Perform a Facelift
Authors: Botti Chiara , Botti Giovanni , Pascali Michele
Published: August 2021

Background

The “time variable” assumes paramount importance, especially regarding facial rejuvenation procedures. Questions regarding the length of recovery time before returning to work, how long the results will last, and the ideal time (age) to undergo this particular type of surgery are the most commonly asked by patients during the initial consultation.

Objectives

The authors endeavored to determine the healing time, optimal age to perform the surgery, and duration of the results after cosmetic face surgery.

Methods

A 35-year observational study of 9313 patients who underwent facial surgeries was analyzed. The principal facial rejuvenation interventions were divided into 2 subgroups: (1) eyelid and periorbital surgery, including eyebrow lift, blepharoplasty, and its variants and midface lift; and (2) face and neck lift. Significant follow-ups were conducted after 5, 10, and 20 years. To evaluate the course of convalescence, the degree of satisfaction with the intervention, and the stability of the results, a questionnaire survey was administered to a sample of 200 patients who underwent face and neck lifts.

Results

The answers given indicated that surgery performed according to rigorous standards allowed for a relatively rapid recovery, and the positive results were stable up to 10 years after surgery. The level of patient satisfaction also remained high even after 20 years.

Conclusions

The “right time” for a facelift, taking into account age, recovery time, and the longevity of the results, is an important consideration for both the patient and the cosmetic surgeon.

Level of Evidence: 4
Functional meta-omics provide critical insights into long- and short-read assemblies
Authors: Galata Valentina , Busi Susheel Bhanu , Kunath Benoît Josef , de Nies Laura , Calusinska Magdalena , Halder Rashi , May Patrick , Wilmes Paul , Laczny Cédric Christian
Published: August 2021

Real-world evaluations of metagenomic reconstructions are challenged by distinguishing reconstruction artifacts from genes and proteins present in situ. Here, we evaluate short-read-only, long-read-only and hybrid assembly approaches on four different metagenomic samples of varying complexity. We demonstrate how different assembly approaches affect gene and protein inference, which is particularly relevant for downstream functional analyses. For a human gut microbiome sample, we use complementary metatranscriptomic and metaproteomic data to assess the metagenomic data-based protein predictions. Our findings pave the way for critical assessments of metagenomic reconstructions. We propose a reference-independent solution, which exploits the synergistic effects of multi-omic data integration for the in situ study of microbiomes using long-read sequencing data.
Phosphorylated TDP-43 aggregates in peripheral motor nerves of patients with amyotrophic lateral sclerosis
Authors: Riva Nilo , Gentile Francesco , Cerri Federica , Gallia Francesca , Podini Paola , Dina Giorgia , Falzone Yuri Matteo , Fazio Raffaella , Lunetta Christian , Calvo Andrea , Logroscino Giancarlo , Lauria Giuseppe , Corbo Massimo , Iannaccone Sandro , Chiò Adriano , Lazzerini Alberto , Nobile-Orazio Eduardo , Filippi Massimo , Quattrini Angelo
Published: August 2021

Phosphorylated TDP-43 (pTDP-43) aggregates in the cytoplasm of motor neurons and neuroglia in the brain are one of the pathological hallmarks of amyotrophic lateral sclerosis. Although the axons exceed the total volume of motor neuron soma by several orders of magnitude, systematic studies investigating the presence and distribution of pTDP-43 aggregates within motor nerves are still lacking. The aim of this study is to define the TDP-43/pTDP-43 pathology in diagnostic motor nerve biopsies performed on a large cohort of patients presenting with a lower motor neuron syndrome and to assess whether this might be a discriminating tissue biomarker for amyotrophic lateral sclerosis and non-amyotrophic lateral sclerosis cases.

We retrospectively evaluated 102 lower motor neuron syndrome patients referred to our centre for a diagnostic motor nerve biopsy. Histopathological criteria of motor neuron disease and motor neuropathy were applied by two independent evaluators, who were blind to clinical data. TDP-43 and pTDP-43 were evaluated by immunohistochemistry, and results compared to final clinical diagnosis.

We detected significant differences between amyotrophic lateral sclerosis and non-amyotrophic lateral sclerosis cases in pTDP-43 expression in myelinated fibres: axonal accumulation was detected in 98.2% of patients with amyotrophic lateral sclerosis versus 30.4% of non-amyotrophic lateral sclerosis samples (P < 0.0001), while concomitant positive staining in Schwan cell cytoplasm was found in 70.2% of patients with amyotrophic lateral sclerosis versus 17.4% of patients who did not have amyotrophic lateral sclerosis (P < 0.001). Importantly, we were also able to detect pTDP-43 aggregates in amyotrophic lateral sclerosis cases displaying normal features at standard histopathological analysis.

Our findings demonstrated that a specific pTDP-43 signature is present in the peripheral nervous system of patients with amyotrophic lateral sclerosis, and could be exploited as a specific, accessible tissue biomarker. The detection of pTDP-43 aggregates within motor nerves of living patients with amyotrophic lateral sclerosis, occurring before axonal degeneration, suggests that this is an early event that may contribute to amyotrophic lateral sclerosis pathogenesis.
The neuroethics of disorders of consciousness: a brief history of evolving ideas
Authors: Young Michael J , Bodien Yelena G , Giacino Joseph T , Fins Joseph J , Truog Robert D , Hochberg Leigh R , Edlow Brian L
Published: August 2021

Neuroethical questions raised by recent advances in the diagnosis and treatment of disorders of consciousness are rapidly expanding, increasingly relevant and yet underexplored. The aim of this thematic review is to provide a clinically applicable framework for understanding the current taxonomy of disorders of consciousness and to propose an approach to identifying and critically evaluating actionable neuroethical issues that are frequently encountered in research and clinical care for this vulnerable population. Increased awareness of these issues and clarity about opportunities for optimizing ethically responsible care in this domain are especially timely given recent surges in critically ill patients with prolonged disorders of consciousness associated with coronavirus disease 2019 around the world. We begin with an overview of the field of neuroethics: what it is, its history and evolution in the context of biomedical ethics at large. We then explore nomenclature used in disorders of consciousness, covering categories proposed by the American Academy of Neurology, the American Congress of Rehabilitation Medicine and the National Institute on Disability, Independent Living and Rehabilitation Research, including definitions of terms such as coma, the vegetative state, unresponsive wakefulness syndrome, minimally conscious state, covert consciousness and the confusional state. We discuss why these definitions matter, and why there has been such evolution in this nosology over the years, from Jennett and Plum in 1972 to the Multi-Society Task Force in 1994, the Aspen Working Group in 2002 and the 2018 American and 2020 European Disorders of Consciousness guidelines. We then move to a discussion of clinical aspects of disorders of consciousness, the natural history of recovery and ethical issues that arise within the context of caring for people with disorders of consciousness. We conclude with a discussion of key challenges associated with assessing residual consciousness in disorders of consciousness, potential solutions and future directions, including integration of crucial disability rights perspectives.
When the brain slows the heart—herpes encephalitis and sinus arrest: a case report
Authors: Braiman Dana , Konstantino Yuval , Westreich Roi
Published: August 2021

Background

Herpes simplex virus (HSV) encephalitis is a known cause of cognitive deterioration, neurological disturbances, and seizures though are rarely associated with sinus node dysfunction.

Case summary

We present a 54-year-old man admitted to the hospital with a 10-day history of fever, confusion, and fatigue, 1 week following a transient loss of consciousness. An initial workup suggested HSV encephalitis and the patient was started on intravenous Acyclovir. Due to his episode of syncope, a 24 h Holter electrocardiogram monitoring was performed. The Holter documented multiple episodes of sinus arrest, with a second episode of syncope noticed by the hospital staff concurrent with the last documented sinus arrest. Following antiviral treatment and resolution of the encephalitis we noticed complete resolution of sinus node dysfunction. We subsequently avoided permanent pacemaker implantation.

Discussion

Our case of proven HSV encephalitis complicated by sinus node arrest and syncope with complete resolution following antiviral treatment suggests no indication for permanent pacemaker implantation. This approach is consistent with data from previously reported cases.
Prediction of first cardiovascular disease event in 2.9 million individuals using Danish administrative healthcare data: a nationwide, registry-based derivation and validation study
Authors: Christensen Daniel Mølager , Phelps Matthew , Gerds Thomas , Malmborg Morten , Schjerning Anne-Marie , Strange Jarl Emanuel , El-Chouli Mohamad , Larsen Lars Bruun , Fosbøl Emil , Køber Lars , Torp-Pedersen Christian , Mehta Suneela , Jackson Rod , Gislason Gunnar
Published: August 2021

Aims

The aim of this study was to derive and validate a risk prediction model with nationwide coverage to predict the individual and population-level risk of cardiovascular disease (CVD).

Methods and results

All 2.98 million Danish residents aged 30–85 years free of CVD were included on 1 January 2014 and followed through 31 December 2018 using nationwide administrative healthcare registries. Model predictors and outcome were pre-specified. Predictors were age, sex, education, use of antithrombotic, blood pressure-lowering, glucose-lowering, or lipid-lowering drugs, and a smoking proxy of smoking-cessation drug use or chronic obstructive pulmonary disease. Outcome was 5-year risk of first CVD event, a combination of ischaemic heart disease, heart failure, peripheral artery disease, stroke, or cardiovascular death. Predictions were computed using cause-specific Cox regression models. The final model fitted in the full data was internally-externally validated in each Danish Region. The model was well-calibrated in all regions. Area under the receiver operating characteristic curve (AUC) and Brier scores ranged from 76.3% to 79.6% and 3.3 to 4.4. The model was superior to an age-sex benchmark model with differences in AUC and Brier scores ranging from 1.2% to 1.5% and −0.02 to −0.03. Average predicted risks in each Danish municipality ranged from 2.8% to 5.9%. Predicted risks for a 66-year old ranged from 2.6% to 25.3%. Personalized predicted risks across ages 30–85 were presented in an online calculator (https://hjerteforeningen.shinyapps.io/cvd-risk-manuscript/).

Conclusion

A CVD risk prediction model based solely on nationwide administrative registry data provided accurate prediction of personal and population-level 5-year first CVD event risk in the Danish population. This may inform clinical and public health primary prevention efforts.
Matrix-Bound Growth Factors are Released upon Cartilage Compression by an Aggrecan-Dependent Sodium Flux that is Lost in Osteoarthritis
Authors: Keppie Stuart J , Mansfield Jessica C , Tang Xiaodi , Philp Christopher J , Graham Helen K , Önnerfjord Patrik , Wall Alanna , McLean Celia , Winlove C Peter , Sherratt Michael J , Pavlovskaya Galina E , Vincent Tonia L
Published: August 2021

Articular cartilage is a dense extracellular matrix-rich tissue that degrades following chronic mechanical stress, resulting in osteoarthritis (OA). The tissue has low intrinsic repair especially in aged and osteoarthritic joints. Here, we describe three pro-regenerative factors; fibroblast growth factor 2 (FGF2), connective tissue growth factor, bound to transforming growth factor-beta (CTGF-TGFβ), and hepatoma-derived growth factor (HDGF), that are rapidly released from the pericellular matrix (PCM) of articular cartilage upon mechanical injury. All three growth factors bound heparan sulfate, and were displaced by exogenous NaCl. We hypothesised that sodium, sequestered within the aggrecan-rich matrix, was freed by injurious compression, thereby enhancing the bioavailability of pericellular growth factors. Indeed, growth factor release was abrogated when cartilage aggrecan was depleted by IL-1 treatment, and in severely damaged human osteoarthritic cartilage. A flux in free matrix sodium upon mechanical compression of cartilage was visualised by 23Na -MRI just below the articular surface. This corresponded to a region of reduced tissue stiffness, measured by scanning acoustic microscopy and second harmonic generation microscopy, and where Smad2/3 was phosphorylated upon cyclic compression. Our results describe a novel intrinsic repair mechanism, controlled by matrix stiffness and mediated by the free sodium concentration, in which heparan sulfate-bound growth factors are released from cartilage upon injurious load. They identify aggrecan as a depot for sequestered sodium, explaining why osteoarthritic tissue loses its ability to repair. Treatments that restore matrix sodium to allow appropriate release of growth factors upon load are predicted to enable intrinsic cartilage repair in OA.

Significance Statement

Osteoarthritis is the most prevalent musculoskeletal disease, affecting 250 million people worldwide.1 We identify a novel intrinsic repair response in cartilage, mediated by aggrecan-dependent sodium flux, and dependent upon matrix stiffness, which results in the release of a cocktail of pro-regenerative growth factors after injury. Loss of aggrecan in late-stage osteoarthritis prevents growth factor release and likely contributes to disease progression. Treatments that restore matrix sodium in osteoarthritis may recover the intrinsic repair response to improve disease outcome.
Use of barcode technology can make a difference to patient safety in the post-COVID era
Authors: Lachman Peter , van der Wilden Els
Published: August 2021

The coronavirus disease 2019 pandemic has demonstrated the value of digital solutions to patient care and to patient safety. Here are many solutions that have yet to be fully implemented. In this commentary, we discuss the value of barcode technology to ensure secure supply chains and the delivery of reliable and efficient processes in healthcare. This will facilitate the implementation of World Health Organization policies on supply chains as well as support initiatives on medication safety.
Community pharmacists’ perceptions and role in the management of common dermatological problems in Lebanon: a cross-sectional study
Authors: Chahine Bahia , Cherfane Michelle , Sakr Fouad , Safwan Jihan , Dabbous Mariam , Akel Marwan , Rahal Mohamad
Published: August 2021

Objective

To explore the types and frequency of dermatologic disorders routinely encountered by community pharmacists in Lebanon, identify their educational preparedness and confidence, reasons for referrals to dermatologists and their attitude toward the potential pharmacist role in the treatment of dermatologic disorders.

Methods

A cross-sectional descriptive study was conducted between June and October 2017. It involved the use of a self-administered questionnaire, distributed to a randomly selected sample of 500 community pharmacists from all Lebanese districts.

Key findings

A total of 456 pharmacists completed the questionnaire. Sixty-four per cent of participants had received a dermatology course at university and 38.7% had undertaken some form of postgraduate education in dermatology. Pharmacists believed that the most commonly encountered disorders were sunburn (22.6%) and acne (15.6%) during spring/summer and skin dryness (18.8%) followed by head lice (13.1%) during autumn/winter. Additionally, more than half of respondents reported that skin-related advice requests were 6–15% of the total advice offered to patients. Sixty-four per cent were confident or extremely confident in advising patients with dermatological complaints. Pharmacists ranked ‘unsure of diagnosis’ as the most common reason for patient referral to dermatologists. Pharmacists who received postgraduate dermatology training had higher self-reported confidence in tackling skin diseases and their treatments (P < 0.05).

Conclusions

Our study revealed that community pharmacists in Lebanon commonly encounter a limited number of dermatologic disorders and the majority believed that they can confidently advise and manage patients. Nonetheless, they admitted a gap in their dermatology education at both undergraduate and postgraduate levels.