bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on solar-ground source heat pump and combined heating system in severe cold area
Authors: Hao Hong , Yu Yang
Published: August 2021

This paper studies the operation strategy and economy of solar-ground source heat pump gas heating system in severe cold region. Two operation modes of the system are introduced: series operation and parallel operation, and the two operation modes are simulated. This paper compares and analyses the heat exchange of the ground pipe, the change of the water temperature at the inlet and outlet of the ground pipe heat exchanger, the heating efficiency coefficient cop and the refrigeration efficiency coefficient EER of the heat pump unit during the five-year operation of the combined heating system, and studies the change of the soil temperature, Finally, the economic analysis is made from the initial investment cost and operation cost of two different heating schemes. The results show that the maximum heat transfer efficiency of the parallel system is 2.5 times that of the serial system, and the total heat transfer between the parallel system and the heat network is 83.2 % higher than that of the serial system. The inlet and outlet water temperature of the buried pipe decreased under both operation modes. After five years of operation, although the operation cost of the parallel combined heating system is higher than that of the serial combined heating system, the parallel combined heating system has more advantages than the serial combined heating system in terms of the overall heating effect of the system and the influence degree of the system on soil temperature.
Research on the material properties of corroded angle steel members of the in-service transmission tower
Authors: Zhu Binrong , Su Zhigang , Huang Guo , Liao Hailin
Published: August 2021

The number of old transmission lines in China is increasing, and corrosion is a common problem on old transmission towers, which reduces the load-bearing performance of the tower and leads to potential safety hazards. The paper conducts investigation and sampling of the actual engineering line towers, analyzes the reasons for the corrosion of the towers, and carries out the tensile test of the specimens, and obtains the relationship curve of the elongation loss ratio, the yield strength loss ratio, the tensile strength loss ratio and the elastic modulus loss ratio with the cross-sectional loss ratio, which provides a basis for the evaluation of the load-bearing performance of the old transmission tower.
Numerical study on 3D water-air two-phase seepage characteristics of undisturbed granite residual soil at REV scale
Authors: Peichen CAI , Yun QUE , Pengfei YANG
Published: August 2021

To reveal the dynamic seepage mechanism of water-gas two-phase in soil, the undisturbed granite residual soil in Fuzhou was selected as the research object. Based on the computer tomography(CT) image and AVIZO-COMSOL interactive docking technology, the Level Set method was used to study the 3D water-gas two-phase seepage characteristics of the undisturbed granite residual soil at the REV scale. The results show that the residual gas in the pores is mainly distributed in blocks on the pore edges, dead corners and sudden changes of pore throats. Among the numerous pores of the REV model, there are only a few major seepage pores, which are generally characterized by wide and straight pores. In different seepage stages, the velocity distribution is different. In general, the flow velocity increases first, then decreases, and then gradually increases. The maximum velocity growth rate and decrease rate are 61.04% and 40.60%. With the increase of seepage time, the saturation of the water phase shows a sharp upward trend, and the saturation of the gas phase shows a sharp downward trend, they both occur in the initial stage of seepage, and then gradually tend to be stable. Finally, the saturation of the water phase and the residual gas phase tend to 91.86% and 8.14% respectively.
Compressive Creep Behavior of Cellulose Fiber Reinforced Concrete
Authors: Bo CHEN , Liping GUO , Wenxiao ZHANG , Yin BAI , Xiongfeng WANG
Published: August 2021

The effect of cellulose fiber on the long-term compressive creep performance of concrete was clarified. For this, the long-term compressive creep properties of four cellulose fiber reinforced concrete (CFRC) groups with contents of 0, 0.9 kg/m3, 1.1 kg/m3, and 1.3 kg/m3 were investigated using a spring creep tester. Loading ages of 7 days, 14 days, and 28 days, and a loading stress ratio of 0.40 were employed. Furthermore, the creep model of CFRC was established. The results revealed that the creep of concrete at three loading ages decreases by 16%, 12%, and 17%, respectively, after adding cellulose fiber to the concrete. With increasing loading age, the difference of creep degree of CFRC with different cellulose fiber content decreased gradually. Furthermore, the range of specific creep decreased from 8 × 10−6 / MPa for a 7 day loading age to 2 × 10−6 / MPa for a 28 day loading age. The change regulation of CFRC creep coefficient was similar to that of the specific creep. The influence of the cellulose fiber on the creep performance of the concrete was reflected in two aspects. On the one hand, the internal curing effect of cellulose fiber can optimize the microstructure of concrete and reduce the creep deformation. On the other hand, the fiber increases the water migration channel and defects of interface transition zone, which will increase the creep deformation. The power exponential function model for CFRC creep provided a good description of the relationship between creep and loading age and holding time. This model can be used to predict the long-term creep of CFRC under different loading ages.
Study on Quality Control of Construction Structure Reconstruction and Reinforcement
Authors: Wei Zhang
Published: August 2021

Compared with the new building project, the overall situation of building structure reinforcement and reconstruction is more complicated, and it will be affected by many different factors, so it is more difficult to reinforce. It can be seen that during the building structure reconstruction and reinforcement, the relevant personnel must fully grasp the specific situation of the building structure and properly cooperate with the professional design and construction, only in this way can the ideal effect be achieved. This paper makes a comprehensive study on the quality control content of building structure reconstruction and reinforcement, hoping that the content in this paper can help the relevant staff and promote the healthy and stable development of China’s construction industry.
Research on the spatial distribution and accessibility of medical institutions in Wuhan based on GIS
Authors: Wang Yi , Wu Changyou
Published: August 2021

To explore the rationality of the spatial distribution structure of medical institutions in Wuhan and provide a reasonable reference basis for the spatial layout of medical institutions. Using GIS spatial analysis methods to study the distribution characteristics and spatial accessibility in Guangzhou. Medical institutions in Wuhan have obvious spatial agglomeration characteristics and are concentrated in the central urban area. The spatial distribution of medical institutions in Wuhan is unbalanced and concentrated in the central urban area. The waste of health resources and the scarcity of health resources exist at the same time. The accessibility and fairness of medical institutions need to be improved, and reasonable planning and adjustment should be made.
Study on flood control projects joint flood control operation of The Daqing river basin
Authors: Zhongbo Zhang , Xiaoyan He , Simin Geng , Shuanghu Zhuang , Hui Li , Yu Tian
Published: August 2021

Baiyangdian Lake is an important pivotal project in the Daqing River Basin. The research on the joint flood control operation of water projects in the Daqing River Basin seems particularly important as higher requirements have been set for the flood control in the basin based on the construction of the Xiong’an New Area. In this paper, a joint flood control operation model was set up and solved with the joint flood control operation objective of minimizing the highest water level of Baiyangdian Lake. A study on the joint flood control operation under different flood conditions was carried out under the premise of ensuring the safety of reservoir projects. The optimal operation can ensure that the Wen’anwa flood storage and detention area will not be opened in the event of a hundred-year flood, reduce the highest water level of Baiyangdian Lake to a certain extent, effectively alleviate the pressure on the flood control of dikes and Baiyangdian Lake and provide support for guaranteeing the flood control safety of the Xiong’an New Area.
Design of portable recyclable drainboard set-up
Authors: Sun Zhuoqi , Wang Mingyuan , Wang Kuanjun , Xi Zunbang , Li Guo , Fu Yuchen , Wang Yajun
Published: August 2021

For the traditional drainboard set-up device obvious disadvantages: the structure is bulky, loading complex, often need drainage plate body, affecting the drainage effect, almost impossible to recycle, poor environmental protection performance, due to the effect of deformation, late work and other devices have interference, the drainage itself difficult to regulate in the process of setting up. In order to achieve the light, automatic, non-destructive and recyclable of drainage plate, improve the obvious shortcomings mentioned above, a series of improvements are made to the drainage plate set-up device. Through the verification of laboratory experiments, the problems such as large, bulky, high vulnerability and low recovery rate are solved, and the laboratory simulation has no suitable equipment, which reduces the space occupancy rate, saves resources and so on, and greatly reduces the cost of experiments. In water engineering applications, this new type of drainboard discount ingress than the existing drainboard plug-in machine, can be a good substitute for improving the status quo of the project.
Simulation and prediction of groundwater pollution based on GMS: a case study in Beijing, China
Authors: Zhao Xiaoning , Wang Daqing , Xu Haoli , Ding Zhibin , Shi Yue , Lu Zhao , Cheng Zijian
Published: August 2021

Groundwater is an important fresh water resource, which is very important for human survival. In this study, the hydrogeological information of the study area was obtained through field investigation and data reference, and the groundwater flow field in the study area was constructed using GMS (Groundwater Modeling Systems) software. The actual drilling water level data was used for verification. Based on the groundwater flow field, combined with pollution source sampling and testing data, a groundwater pollutant transport model was constructed, and the pollution situation was comprehensively evaluated. The results showed that once the landfill leachate and lead-acid battery plant waste liquid leaked in the study area, the groundwater in more than 40% of the study area will be greatly affected and it was not easy to recover. Therefore, predicting and simulating the transport of groundwater pollutants has a certain value, and can provide a scientific basis for preventing and controlling environmental degradation and protecting groundwater resources.
Hydrogeochemical characterization of Tai’an Pumped Storage Power Station reservoir and the implications for Reservoir Water Leakage
Authors: Zhang Gucheng , Yang Zhangyang , Li Guangkai , Zheng Xiaohe , Mao Changping
Published: August 2021

Reservoir leakage is typically a potential risk to reservoir operation in the world. In this study, Tai’an pumped storage power station reservoir was selected as an example to analyze the chemical characteristics of various waters in detail. The results showed that silicate rock weathering was the main source of water chemical ions of reservoir water, groundwater and Bashangoue water. Hydrogeochemical analysis showed that the water samples of the right bank gallery and measuring weir behind dam came from the reservoir water leakage, measuring weir of bottom gallery, B2 branch pipe gallery and No.6 construction hole water samples did not originate from reservoir water but from groundwater. The research results are of great guiding significance for guiding the diagnosis and control of reservoir leakage.
Seepage analysis of Baihetan arch dam
Authors: Wu Janming , Li Guo , Tan Yaosheng , Liu Chunfeng , Pei Lei , Song Liangfeng , Hu Yu
Published: August 2021

The 289m high arch dam at Baihetan has good indicators before water storage, but after water storage, seepage gradually occurs in the dam body and foundation parts, which has some adverse effects on the safety of the dam. In this paper, five monitoring instruments were used to analyze the overall dam properties during the water storage process, including the pre-buried foundation corridor pressure tube, the dam base seepage pressure gauge, the seepage pressure tube around the dam, the dam water measuring weir and the dam base drainage hole. The results show that: the seepage pressure level before the curtain of the dam base is seriously affected by the upstream water level, Post-curtain and post-drainage lift pressure is less affected by upstream water level; the flow rate of the dam measuring weir and the dam base drainage hole is more affected by the upstream water level, and the trend of flow rate changes is more consistent with the trend of the upstream water level; the rest of the parts are less affected by the upstream water level.
Study on hydrological process simulation of lumped hydrological model in Wujiang River Basin
Authors: Sun Guangru , Wen Jie , Yang Jinjin , Hou Siyu , Zhang Weihua
Published: August 2021

In this paper, AWBM, Sacramento, Simhyd and TANK models were used to simulate the runoff process of Wujiang River Basin from 1991 to 2004. The results show that the Nash-Sutcliffe efficiency coefficients and the relatives of the Simhyd model during verification period are 0.844 and 9.015% respectively, which meet the requirements and achieve the optimal effect. While the AWBM model has a poor performance in the simulation of runoff during flood rise period, a better performance in the simulation of runoff during flood recession period. Sacramento model has obvious “equifinality for different parameters” phenomenon due to its large number of parameters.
Research on Innovation of Experimental System Based on Vacuum Preloading Method
Authors: Fu Yuchen , Wang Mingyuan , Hu Yu , Wang Yajun
Published: August 2021

Aiming at the problems of traditional vacuum pre-compression technology, which is difficult to visually observe the material curing effect and low sampling accuracy, this paper independently developed a set of new modular transparent model barrels and controllable vacuum pressure manifolds. Based on traditional experimental methods, Improve the model barrels and vacuum dividers in the experimental system. Experimental research shows that the improved experimental system not only solves the shortcomings of the traditional experimental system, but also can be assembled on site, which is beneficial to the areas with abundant water resources. The project of reclaiming land from the sea provides support, which has certain production and economic benefits.
Decoloration behavior of hydrolyze sediment of ferric salt doped with magnetite on dye wastewater
Authors: Jiang Bo , Feng Shanghua , Zhang Jianping
Published: August 2021

Based on the strong adsorption capacity of colloidal precipitate formed by hydrolysis of iron salts (FHCP), a kind of composite material of FHCP/Fe3O4 was prepared and used in the decoloration of dye wastewater. The results showed that FHCP/Fe3O4 had high decolorization efficiency for anionic dyes. FHCP/Fe3O4 was more suitable for the decolorization of anionic dyes in acidic environment. The impact order of foreign ions on the decolorization performance of FHCP/Fe3O4 was as follows, that is HCO3
- >SO4
2- >Cl-. The fitting of adsorption kinetic of anionic dyes on FHCP/Fe3O4 matched with the pseudo-second-order kinetic equation.
Sensitivity analysis of leakage of rockfill dam caused by composite geomembrane defect
Authors: Jie Yang , Guang Cheng , Pengli Zhang , Jiaming Wang
Published: August 2021

To study the influence of different geomembrane defects on the seepage field of a typical concrete inclined wall rockfill dam with a dam height of 85m, the saturated-unsaturated seepage finite element theory is applied to construct a three-dimensional numerical calculation model, and the seepage field of the dam under different geomembrane defects is numerically simulated and analysed. The calculation conditions of geomembrane defect size, head height, defect position, defect number and spacing are worked out respectively, and then the influence law of composite geomembrane breakage on dam seepage under pressure head is analysed. The results of the calculation model show that when the composite geomembrane has a single size defect and different position defect. The leakage caused by defects is relatively small, which has little effect on the overall seepage of the dam; When there are many defects in composite geomembrane, there is a linear relationship between the number of defects and the seepage of the dam body. When the defects are more concentrated, the phenomenon of concentrated seepage may occur, and the seepage of the dam body changes obviously.
Research on water hammer protection for a long-distance water supply system of a deep well pump group
Authors: Li Gaohui , Wu Xumin , Li Luming , Qiu Weixin , Cui Weijie
Published: August 2021

This paper is based on the hydraulic characteristics of the multi-pump group, high head, and small flow of a long-distance water supply system in a deep well pump group. Fisrtly a calculation analysis model is established, and then a non-water hammer protection measure is carried out for its typical controlled working condition system. The pressure distribution characteristics of the water supply system reveal that the hydraulic transition process of the water supply system of the deep well pump group is even worse. Then, according to its hydraulic characteristics, a cost-effective water hammer protection measure-a one-way surge tank and air valve combined protection plan was selected. Finally, the calculation and analysis of the hydraulic transition process of setting the system one-way surge tank and air valve joint protection plan are carried out. The calculation results show that the one-way surge tank and air valve combined to protect water hammer have a good effect on this water supply system. It provides a new idea for the water hammer protection setting of the long-distance water supply system of the deep well pump group with high water head and small flow.
Zoning based cascade infrastructure system design for urban waterlogging prevention
Authors: Tian Ziyang , Chu Junying , Wang Hao , Zhou Zuhao
Published: August 2021

With the development of global climate change and urbanization in China, urban waterlogging caused by rainstorm has a serious impact on the safety of people’s life and property and the development of social and economic. Based on the hydraulic model, taking Xining City as an example, a set of multi-layer flood prevention infrastructure construction technology system is proposed, in which the microscale-drainage-system mainly includes the sponge transformation of building blocks, the construction of sponge park; the mesoscale-drainage-system mainly includes the transformation of pipe system for different return periods, the transformation of combined flow and separate flow system; the macroscale-drainage-system mainly includes utility tunnel system, natural and artificial storage facilities. Through quantitative evaluation of rainstorm with 50 year return period, under the construction of microscale-drainage-system and mesoscale-drainage-system with different return period index, the total drainage capacity increased from 1.407 million m3 to 1.573 million m3 and 1.830 million m3. The total accumulated water is 1.073 million m3 and 0.816 million m3 respectively, which are less than 1.173 million m3 of macroscale-drainage-system new storage capacity.
Analysis of anomalies measured by the osmometer in a roller compacted concrete arch dam
Authors: Shidong Han , Yuanxian Li , Hanwei
Published: August 2021

The water permeability of the RCC dam layer and joint surface is high, which often becomes the main channel of dam body seepage, and its safety monitoring is important. Based on the monitoring data of the osmometer of a roller compacted concrete (RCC) arch dam, this paper analyzes the abnormal seepage pressure of the dam body, and introduces the relevant inspection and treatment scheme, which can provide a reference for the construction and operation of other RCC dams.
Discussion on Electricity Spot Market Mode Adapting to Large-scale Renewable Energy Consumption
Authors: Hongxia LI , Na LI , Xiangcheng ZHANG , Ying YANG , Guiyou XIAO , Xinyu MENG , Xue MA , Yuguo CHEN , Yuping WEI
Published: August 2021

With the implementation of the “Thirteenth Five-Year Plan”, the scale of my country’s renewable energy installed capacity continues to expand, and the responsibility for consuming renewable energy power is becoming higher and higher. Promoting the reform of the electricity spot market provides a good opportunity to realize the consumption of large-scale renewable energy. This article aims at the northwest region where renewable energy accounts for a relatively high proportion in my country, and clarifies the factors that inhibit the consumption of renewable energy. Based on the investigation of the typical foreign power spot market model, a power spot market model suitable for large-scale renewable energy is proposed. According to the actual data of a province’s power grid in the northwest region, the day-ahead spot market under different models was cleared separately. The results show that the centralized market model is more suitable for large-scale renewable energy grid-connected consumption, and is conducive to promoting energy conservation and emission reduction and reducing power generation costs.
Key components of integrated energy system’s source side and their influence on integrated energy system
Authors: Xie Pingping , Yi Xinyi , Mao Tian , Lu Siyu
Published: August 2021

Integrated energy supply and emerging new energy is a sign of transformation of energy system for environmental protection. This paper firstly models the key components of source side in integrated energy system. On the one hand, this paper models integrated energy supply and energy conversion devices involving multiple energy systems, on the other hand, it models new energy which is rapidly growing, so that all of these energy supply methods can serve the coordinated dispatch of integrated energy system. Then this paper focuses on CHP with heat storage which is a typical energy supply method involving both integrated energy supply and energy conversion. Through case study, we find that the heat storage system can bring friendly interaction between heat and power system, enhance the flexibility of integrated energy system, and decouple complex integrated energy system, so as to improve the social economic welfare.
Study on the willingness of energy conservation and emission reduction of university students in Wuhan under the background of “carbon peak” and “carbon neutral” strategy-Based on K-means clustering and principal component analysis
Authors: Xu Yihong , Hu Shujuan , Yu Rongxiao
Published: August 2021

An important means to achieve the goal of “carbon peak” and “ carbon neutral ” is energy conservation and emission reduction. It is an indispensable part of the vision of “carbon peak” and “ carbon neutral ” to study the willingness of college students to save energy and reduce emissions, understand the current situation of their awareness of conservation and advocate a green low-carbon lifestyle. On the basis of literature review, 642 samples of university students in Wuhan were investigated by using probability sampling, an evaluation system of college students’ willingness to save energy and reduce emission was established, SPSS was used for statistical analysis, and the reliability and validity were feasible. Based on K-means clustering analysis to analyze the cognitive characteristics of energy conservation and emission reduction of Wuhan college students, and based on the principal component analysis to comprehensively evaluate their willingness to save energy and reduce emissions, the conclusion is drawn that “it is feasible for college students to develop the willingness of energy conservation and emission reduction on the whole”.
Studies on cooling hours and switch temperature of cooling-tower cooling supply in Guizhou typical climate district
Authors: Su Ying , Hu Cheng , Li Lei , Mao Ruiyong
Published: August 2021

According to the meteorological parameters of Guizhou Province and the feasibility of developing cooling tower cooling in 4 typical cities and towns in thermal engineering districts, we found the following situation. First of all, if calculated according to the accumulated hours of 8,760 hours of wet bulb temperature below 14°C (including 14°C), Guiyang City (moderate area) has a total of 4327 hours, accounting for 49.39% of the total. Zunyi City (a region with hot summer and cold winter) has a total of 4469 hours, accounting for 51.02% of the whole year. For areas with hot summer and warm winter, such as Xingyi City (a hot winter and warm area), a total of 4404 hours, accounting for 50.27% of the whole year. Weining County (an area with cool summer and cold winter) has a total of 6792 hours, accounting for 77.53% of the total. In addition, if it is in winter (December, January and February), when the wet bulb temperature is 14°c, the cooling hours for Guiyang, Xingyi, Zunyi and Weining are 2152h, 2159h, 2130h, 2160h, which accounting for 97.46%, 99.95%, 98.61% and 100% of the cooling hours in winter. With the help of the above data, we can find that, first of all, these cities have little difference in the number of cooling hours in different climate zones in winter, and they all have the possibility of adopting cooling tower cooling technology. Secondly, in the transitional season, when the wet bulb temperature is 14°c as the switching temperature, the cooling hours of Guiyang, Xingyi, Zunyi and Weining are 2175h, 2232h, 2339h, 3858h, respectively. It can be said that these cities have the possibility of adopting cooling tower cooling technology. It is worth mentioning that in the transitional season, the cool summer and cold winter areas represented by Weining have more obvious advantages in climate and energy saving using cooling tower cooling technology.
Optimal Allocation of Distributed Energy Storage Capacity in Power Grid With High Proportion of New Energy
Authors: Jia Yunhui
Published: August 2021

In order to reduce the waste of power resources caused by unreasonable capacity allocation, an optimal allocation method of distributed energy storage capacity in power grid with high proportion of new energy is proposed. Taking wind and solar power generation as the research object, the wind power generation model is established by using Weibull algorithm, the photovoltaic power generation model is established by using beta algorithm, and the energy storage system model is constructed based on the state of energy storage device. The economic benefits of power grid are taken as the objective function to constrain the grid side, DG and energy storage. On this basis, the model parameters are optimized by using particle swarm optimization algorithm, Finally, the optimal configuration of distributed energy storage capacity is realized. The experimental results show that the proposed method can quickly calculate the optimal energy storage configuration under the condition of constant power shortage rate, and the reduced economic loss increases significantly with the increase of power shortage rate. It has a certain research value.
Real-time coordination optimization method of active distribution network considering different stakeholders
Authors: Sun Cheng , Su Shi
Published: August 2021

In order to reduce the impact of renewable energy output and load forecasting error on the network operation optimization and realize the mutual benefit and win-win situation of multiple stakeholders, a real-time coordination optimization method of active distribution network considering different stakeholders is proposed in this paper. Firstly, the daily real-time coordination and optimization framework of active distribution network is proposed. Then, the intraday real-time rolling two-level optimal scheduling model was solved by nonlinear particle swarm optimization and primal dual interior point method. The results of the calculation examples show that the proposed scheduling model and method can maximize the common interests of different subjects of the distribution network and flexible resources, so that the network can guarantee lower operating costs on the basis of safe operation.
A Machine Learning Approach to the Classification of Acute Leukemias and Distinction From Nonneoplastic Cytopenias Using Flow Cytometry Data
Authors: Monaghan Sara A , Li Jeng-Lin , Liu Yen-Chun , Ko Ming-Ya , Boyiadzis Michael , Chang Ting-Yu , Wang Yu-Fen , Lee Chi-Chun , Swerdlow Steven H , Ko Bor-Sheng
Published: August 2021

Objectives

Flow cytometry (FC) is critical for the diagnosis and monitoring of hematologic malignancies. Machine learning (ML) methods rapidly classify multidimensional data and should dramatically improve the efficiency of FC data analysis. We aimed to build a model to classify acute leukemias, including acute promyelocytic leukemia (APL), and distinguish them from nonneoplastic cytopenias. We also sought to illustrate a method to identify key FC parameters that contribute to the model’s performance.

Methods

Using data from 531 patients who underwent evaluation for cytopenias and/or acute leukemia, we developed an ML model to rapidly distinguish among APL, acute myeloid leukemia/not APL, acute lymphoblastic leukemia, and nonneoplastic cytopenias. Unsupervised learning using gaussian mixture model and Fisher kernel methods were applied to FC listmode data, followed by supervised support vector machine classification.

Results

High accuracy (ACC, 94.2%; area under the curve [AUC], 99.5%) was achieved based on the 37-parameter FC panel. Using only 3 parameters, however, yielded similar performance (ACC, 91.7%; AUC, 98.3%) and highlighted the significant contribution of light scatter properties.

Conclusions

Our findings underscore the potential for ML to automatically identify and prioritize FC specimens that have critical results, including APL and other acute leukemias.
Using Real-Time Area VOC Measurements to Estimate Total Hydrocarbons Exposures to Workers Involved in the Deepwater Horizon Oil Spill
Authors: Ramachandran Gurumurthy , Groth Caroline P , Huynh Tran B , Banerjee Sudipto , Stewart Patricia A , Engel Lawrence S , Kwok Richard K , Sandler Dale P , Stenzel Mark
Published: August 2021

Even though the Deepwater Horizon oil spill response and clean-up (OSRC) had one of the largest exposure monitoring efforts of any oil spill, a number of exposure groups did not have sufficient personal data available or there were gaps in days measured to adequately characterize exposures for the GuLF STUDY, an epidemiologic study investigating the health of the OSRC workers. Area measurements were available from real-time air monitoring instruments and used to supplement the personal exposure measurements.

Objectives

The objective was to present a method that used real-time volatile organic compounds (VOCs) area measurements transformed to daily total hydrocarbons (THC) time-weighted averages (TWAs) to supplement THC personal full-shift measurements collected using passive charcoal badges. A second objective was to develop exposure statistics using these data for workers on vessels piloting remotely operated vehicle (ROV) vessels and other marine vessels (MVs) not at the job title level, but at the vessel level.

Methods

From hourly vessel averages derived from ~26 million real-time VOC measurements, we estimated full-shift VOC TWAs. Then, we determined the relationship between these TWAs and corresponding full-shift THC personal measurements taken on the same vessel-day. We used this relationship to convert the full-shift VOC measurements to full-shift ‘THC’ TWA estimates when no personal THC measurements existed on a vessel-day. We then calculated arithmetic means (AMs) and other statistics of THC exposures for each vessel.

Results

The VOC-derived estimates substantially supplemented the THC personal measurements, with the number of vessel-days for which we have exposure estimates increasing by ~60%. The estimates of the AMs are some of the highest observed in the GuLF STUDY. As expected, the AMs decreased over time, consistent with our findings on other vessels.

Conclusions

Despite the inherent limitations of using real-time area measurements, we were able to develop additional daily observations of personal THC exposures for workers on the ROV vessels and other MVs over time. The estimates likely resulted in more representative estimates of the AMs in the GuLF STUDY. The method used here can be applied in other occupational settings and industries for personal exposure estimation where large amounts of area measurements and more limited numbers of personal measurements are available.
Theh-Restricted Connectivity of a Class of Hypercube-Based Compound Networks
Authors: Li Xiaowang , Zhou Shuming , Ma Tianlong , Guo Xia , Ren Xiangyu
Published: August 2021

For the multiprocessor systems modeled by interconnection networks, one of the important properties is the characterization of fault tolerability. Connectivity, as an important parameter to evaluate fault tolerability, has witnessed research achievements. To make the evaluation more practical, conditional connectivity has been promisingly proposed. As one kind of conditional connectivity, $h$-restricted connectivity of a connected graph $G$, denoted by $\kappa ^h (G)$, is defined as the cardinality of the minimum vertex cut set $F$ such that $\delta (G-F)\geq h$. In this paper, we establish a universally $h$-restricted connectivity for a class of hypercube-based compound networks, in which the well-known networks, such as hierarchical cubic network $HCN(n, n)$ and its generalization complete cubic network $CCN(n)$, are involved.
Intrastent haematoma after treatment with a drug-eluting balloon for in-stent restenosis: a case report
Authors: Hong Xu-Lin , Fu Guo-Sheng , Li Zhan-Lu , Zhang Wen-Bin
Published: August 2021

Background

Intrastent haematoma after dilatation of in-stent restenosis (ISR) is rarely reported and the optimal treatment for this condition remains unclear.

Case summary

We present the case of an 87-year-old man with in-stent subtotal occlusion of left circumflex. He experienced chest pain after drug-eluting balloon was released in the stent. Intravascular ultrasound revealed intrastent haematoma, which was not relieved with a cutting balloon but completely sealed by an Endeavor Resolute stent.

Discussion

Intrastent haematoma after dilatation of ISR is rare. Reimplantation of stent seems the best method to solve this problem. Intravascular ultrasound imaging may provide insight into the cause of ISR and guide the treatment.
Incidence, associated outcomes, and predictors of upper gastrointestinal bleeding following acute myocardial infarction: a SWEDEHEART-based nationwide cohort study
Authors: Sarajlic Philip , Simonsson Moa , Jernberg Tomas , Bäck Magnus , Hofmann Robin
Published: August 2021

Aims

Of all spontaneous bleeding complications in patients with acute myocardial infarction (MI), upper gastrointestinal bleeding (UGIB) is common and of specific interest since it could be prevented by several prophylactic measures. We aimed to determine the incidence, associated outcomes, and predictors of UGIB following acute MI.

Methods and results

All patients with acute MI enrolled in the SWEDEHEART (Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies) registry from January 2007 to June 2016 and discharged alive on any antithrombotic therapy (n = 149 477) were followed regarding UGIB for 1 year. Associated outcomes were determined by Cox proportional hazards regression with UGIB as a time-dependent covariate, adjusting for baseline characteristics, invasive treatment, and medical treatment at discharge. Predictors of UGIB were determined by logistic regression and machine learning models.

At 1 year, UGIB had occurred in 2230 patients (cumulative incidence 1.5%) and was significantly associated with an increased risk of all-cause death [hazard ratio (HR) 2.86, 95% confidence interval (CI) 2.58–3.16] and stroke (HR 1.80, 95% CI 1.32–2.45) but not with recurrent MI (HR 1.17, 95% CI 0.97–1.42). The most important predictors of UGIB were haemoglobin, age, systolic blood pressure, blood glucose, smoking status, previous upper gastrointestinal bleeding, and antithrombotic and gastroprotective treatment.

Conclusion

After acute MI, readmission because of UGIB is common and significantly associated with poor prognosis. By using machine learning in addition to traditional logistic regression, new predictors of UGIB, such as blood glucose and smoking status, were identified.
Vaccine-induced immune thrombotic thrombocytopenia: current evidence, potential mechanisms, clinical implications, and future directions
Authors: Marchandot Benjamin , Curtiaud Anais , Trimaille Antonin , Sattler Laurent , Grunebaum Lelia , Morel Olivier
Published: August 2021

Vaccine-induced immune thrombotic thrombocytopenia (VITT) (also termed thrombosis with thrombocytopenia syndrome or vaccine-induced thrombotic thrombocytopenia or vaccine-induced immune thrombocytopenia) is characterized by (i) venous or arterial thrombosis; (ii) mild-to-severe thrombocytopenia; (iii) positive antiplatelet factor 4 (PF4)–polyanion antibodies or anti-PF4–heparin antibodies detected by the HIT (heparin-induced thrombocytopenia) ELISA; (iv) occurring 5–30 days after ChAdOx1 nCoV-19 (AstraZeneca) or Ad26.COV2.S (Johnson & Johnson/Janssen) vaccination. VITT’s incidence is 1 per 100 000 vaccinated people irrespective of age and up to 1 in 50 000 for people <50 years of age with the AstraZeneca COVID-19 vaccine. The exact mechanism by which adenovirus-vectored COVID-19 vaccines trigger this syndrome is still unclear, as for the increased risk for acute cerebral sinus venous thrombosis and splanchnic vein thrombosis as compared to other locations of venous thrombotic events. VITT is associated with the detection of anti-PF4 antibodies, unrelated to previous use of heparin therapy. PF4 antibodies are thought to activate platelets via the platelet FcγRIIA receptors leading to further platelet activation that causes thrombosis and thrombocytopenia.
Antibiotic prophylaxis based on individual infective risk stratification in cardiac implantable electronic device: the PRACTICE study
Authors: Malagù Michele , Vitali Francesco , Brieda Alessandro , Cimaglia Paolo , De Raffele Martina , Tazzari Enea , Musolino Cristina , Balla Cristina , Serenelli Matteo , Cultrera Rosario , Rapezzi Claudio , Bertini Matteo
Published: August 2021

Aims

In patients undergoing cardiac implantable electronic device (CIED) intervention, routine pre-procedure antibiotic prophylaxis is recommended. A more powerful antibiotic protocol has been suggested in patients at high risk of infection. Stratification of individual infective risk could guide the prophylaxis before CIED procedure.

Methods and results

Patients undergoing CIED surgery were stratified according to the Shariff score in low and high infective risk. Patients in the ‘low-risk’ group were treated with only two antibiotic administrations while patients in the ‘high-risk’ group were treated with a prolonged 9-day protocol, according to renal function and allergies. We followed-up patients for 250 days with clinical outpatient visit and electronic control of the CIED. As primary endpoint, we evaluated CIED-related infections. A total of 937 consecutive patients were enrolled, of whom 735 were stratified in the ‘low-risk’ group and 202 in the ‘high-risk’ group. Despite different risk profiles, CIED-related infection rate at 250 days was similar in the two groups (8/735 in ‘low risk’ vs. 4/202 in ‘high risk’, P = 0.32). At multivariate analysis, active neoplasia, haematoma, and reintervention were independently associated with CIED-related infection (HR 5.54, 10.77, and 12.15, respectively).

Conclusion

In a large cohort of patients undergoing CIED procedure, an antibiotic prophylaxis based on individual stratification of infective risk resulted in similar rate of infection between groups at high and low risk of CIED-related infection.
A reference genome for the nectar-robbing Black-throated Flowerpiercer (Diglossa brunneiventris)
Authors: Hiller Anna E , Brumfield Robb T , Faircloth Brant C
Published: August 2021

Black-throated Flowerpiercers (Diglossa brunneiventris) are one species representing a phenotypically specialized group of tanagers (Thraupidae) that have hooked bills which allow them to feed by stealing nectar from the base of flowers. Members of the genus are widely distributed in montane regions from Mexico to northern Argentina, and previous studies of Diglossa have focused on their systematics, phylogenetics, and interesting natural history. Despite numerous studies of species within the genus, no genome assembly exists to represent these nectivorous tanagers. We described the assembly of a genome sequence representing a museum-vouchered, wild, female D. brunneiventris collected in Peru. By combining Pacific Biosciences Sequel long-read technology with 10× linked-read and reference-based scaffolding, we produced a 1.08 Gbp pseudochromosomal assembly including 600 scaffolds with a scaffold N50 of 67.3 Mbp, a scaffold L50 of 6, and a BUSCO completeness score of 95%. This new assembly improves representation of the diverse species that comprise the tanagers, improves on scaffold lengths and contiguity when compared to existing genomic resources for tanagers, and provides another avenue of research into the genetic basis of adaptations common to a nectivorous lifestyle among vertebrates.
Admixture mapping reveals loci for carcass mass in red deer x sika hybrids in Kintyre, Scotland
Authors: McFarlane S Eryn , Pemberton Josephine M
Published: August 2021

We deployed admixture mapping on a sample of 386 deer from a hybrid swarm between native red deer (Cervus elaphus) and introduced Japanese sika (Cervus nippon) sampled in Kintyre, Scotland to search for quantitative trait loci (QTLs) underpinning phenotypic differences between the species. These two species are highly diverged genetically [Fst between pure species, based on 50K single nucleotide polymorphism (SNPs) = 0.532] and phenotypically: pure red have on average twice the carcass mass of pure sika in our sample (38.7 kg vs 19.1 kg). After controlling for sex, age, and population genetic structure, we found 10 autosomal genomic locations with QTL for carcass mass. Effect sizes ranged from 0.191 to 1.839 kg and as expected, in all cases the allele derived from sika conferred lower carcass mass. The sika population was fixed for all small carcass mass alleles, whereas the red deer population was typically polymorphic. GO term analysis of genes lying in the QTL regions are associated with oxygen transport. Although body mass is a likely target of selection, none of the SNPs marking QTL are introgressing faster or slower than expected in either direction.
One year of sound recorded by a mermaid float in the Pacific: hydroacoustic earthquake signals and infrasonic ambient noise
Authors: Pipatprathanporn Sirawich , Simons Frederik J
Published: August 2021

A fleet of autonomously drifting profiling floats equipped with hydrophones, known by their acronym mermaid, monitors worldwide seismic activity from inside the oceans. The instruments are programmed to detect and transmit acoustic pressure conversions from teleseismic P wave arrivals for use in mantle tomography. Reporting seismograms in near-real time, within hours or days after they were recorded, the instruments are not usually recovered, but if and when they are, their memory buffers can be read out. We present a unique 1-yr-long data set of sound recorded at frequencies between 0.1 and 20 Hz in the South Pacific around French Polynesia by a mermaid float that was, in fact, recovered. Using time-domain, frequency-domain and time-frequency-domain techniques to comb through the time-series, we identified signals from 213 global earthquakes known to published catalogues, with magnitudes 4.6–8.0, and at epicentral distances between 24° and 168°. The observed signals contain seismoacoustic conversions of compressional and shear waves travelling through crust, mantle and core, including P, S, Pdif, Sdif, PKIKP, SKIKS, surface waves and hydroacoustic T phases. Only 10 earthquake records had been automatically reported by the instrument—the others were deemed low-priority by the onboard processing algorithm. After removing all seismic signals from the record, and also those from other transient, dominantly non-seismic, sources, we are left with the infrasonic ambient noise field recorded at 1500 m depth. We relate the temporally varying noise spectral density to a time-resolved ocean-wave model, WAVEWATCH III. The noise record is extremely well explained, both in spectral shape and in temporal variability, by the interaction of oceanic surface gravity waves. These produce secondary microseisms at acoustic frequencies between 0.1 and 1 Hz according to the well-known frequency-doubling mechanism.
GTXplorer: A portal to navigate and visualize the evolutionary information encoded in fold A glycosyltransferases
Authors: Taujale Rahil , Soleymani Saber , Priyadarshi Amitabh , Venkat Aarya , Yeung Wayland , Kochut Krzysztof J , Kannan Natarajan
Published: August 2021

Glycosyltransferases (GTs) play a central role in sustaining all forms of life through the biosynthesis of complex carbohydrates. Despite significant strides made in recent years to establish computational resources, databases and tools to understand the nature and role of carbohydrates and related glycoenzymes, a data analytics framework that connects the sequence-structure–function relationships to the evolution of GTs is currently lacking. This hinders the characterization of understudied GTs and the synthetic design of GTs for medical and biotechnology applications. Here, we present GTXplorer as an integrated platform that presents evolutionary information of GTs adopting a GT-A fold in an intuitive format enabling in silico investigation through comparative sequence analysis to derive informed hypotheses about their function. The tree view mode provides an overview of the evolutionary relationships of GT-A families and allows users to select phylogenetically relevant families for comparisons. The selected families can then be compared in the alignment view at the residue level using annotated weblogo stacks of the GT-A core specific to the selected clade, family, or subfamily. All data are easily accessible and can be downloaded for further analysis. GTXplorer can be accessed at https://vulcan.cs.uga.edu/gtxplorer/ or from GitHub at https://github.com/esbgkannan/GTxplorer to deploy locally. By packaging multiple data streams into an accessible, user-friendly format, GTXplorer presents the first evolutionary data analytics platform for comparative glycomics.