bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetic model of methane explosion in a spheroidal explosion tank
Authors: Zhang Xin-Hai , Dou Kai , Luo Zhen-min , Cheng Fang-Ming , Xue Han-ling
Published: February 2021

Methane explosion is studied with a 20-liter content, spheroidal explosion tank. Mixture of methane with oxygen at varied ratio is detonated in the enclosed tank while pressure inside the tank is real-time recorded during the experiments. Temperature and conversion rate of the methane inside the tank during the explosion is calculated according to actual gas equation of state and energy conservation equation. Kinetic equations of the explosion process are derived among conversion rate, species concentration and temperature. Kinetic parameters of the steadily accelerating phase of the explosion process, including the apparent equilibrium constant and enthalpy change, as well as activation energy and pre-exponential factor, are calculated based on kinetic equations and experimental data.
Analysis of the influence of different control modes on the transient power characteristics of DFIG
Authors: Li Zhiping , Cao Na
Published: February 2021

In the event of failure, the doubly-fed Induction Generator (DFIG) with low voltage ride through (LVRT) ability will have different effects on the parallel network characteristics due to the different control mode. In order to analyze the influence of different control modes on the transient power characteristics of DFIG, three kinds of transient response states of wind power system under grid fault are modeled by using power superposition principle based on RSC / GSC controller sampling link and PWM small inertia link, and the accurate transient power response models of different control modes are obtained. The accuracy of the model is verified by simulation with PSCAD/EMTDC, and the influence of control mode on system frequency stability is analyzed.
Probabilistic Load Flow Analysis for Power System Containing Wind Farms Based on Cumulant Method
Authors: Gao Ming , Lv Pan , Zhou Zhuan , Li Jingya , Xue Jingjie , Zhang Bo , Sun Donglei
Published: February 2021

In this paper, a probabilistic load flow computation method based on the cumulants and Edgeworth expansion theory is put forward, and is used in the analysis of system containing wind farms composed of doubly-fed induction generator. Firstly a 2-parameter Weibull function is adopted to fit the random distribution of wind speed, and then the probabilistic model for wind power generator can be established based on active power output characteristic of wind power generator. Based on the linearized AC load flow model, analysis for IEEE 30-node system with wind farm is carried out. Finally the method is compared with Monte-Carlo simulation method, and the effects of wind farms integrated to the operation of power system is analysed in detail.
Experimental study on broaching self-locking anchor rod with mega prestressing force
Authors: Chen Wanbo , Liao Jiehong , Zhou Jianbo
Published: February 2021

In order to solve the problem of applying super-tonnage prestressing force to the gate pier in the process of dam reinforcement, this paper presents a comparative study on the three groups of test specimens of prestressed counterbore self-locking anchor rod and unbonded prestressed anchor cable. T show: (a)both methods satisfy the needs of applying prestress, the experiment conducted on the gate pier that is to be renovated has tested the prestress loss of two schemes and the concrete stress in both free section and anchor section after applying the prestress. The results and counterbore self-locking anchor rod boasts shorter anchorage section and better applicability. (b) the anchorage sections of two schemes generate additional tensile stress, and the maximum additional tensile stress in the anchor rod features 54% less than that of anchor cable, smaller range of additional tensile stress and more reasonable stress state of concrete than that of anchor cable.
Research on Simulation of Heat Transfer Characteristics of Intermittent Spray Cooling
Authors: Han Fucheng , Dong Haihong , Ma Fan
Published: February 2021

Intermittent spray cooling is a new type cooling technology with the energy-saving advantage which can enhance the spray cooling performance and reduce energy was established consumption. In this paper, the three-dimensional simulation model of intermittent spray cooling, and it is the first time using the simulation method to study the heat transfer characteristics of intermittent spray cooling. The simulation results show that intermittent spray cooling effect can be optimized by adjusting spray cycle and duty ratio, and there is the optimal spray cycle and duty ratio at lower flow rate. The simulation results were compared with the experimental results under the same working conditions, and the calculation error was discussed, which is permitted for engineering application.
Study on the Preparation and Performance of An Early Strength Agent for Liquid Alkali-Free Accelerator
Authors: Jiang Yu , Deng Lei , Chen Wenhong , Li Jianmei
Published: February 2021

An early strength agent applied to liquid alkali-free setting accelerator was synthesized at 60°C-70°C by taking methacrylic acid, silicic acid, calcium hydroxide, and hydroxyethyl ethylenediamine as the raw materials. The experiment showed that after 4% early strength agent was added into the accelerator, the 1d compressive strength and 28d compressive strength of the quick-setting mortar and shotcrete were obviously improved, so the industrialized application of this early strength agent can be realized.
Influence of different material proportions on the physical properties of water-saving roof greening substrates
Authors: Wang Bin , Liu Yongxia , Wen Yonghong , Yan Hao
Published: February 2021

The choice of roof greening substrate is the key to effective roof greening. To fully analyze the influence of different material proportions on the physical properties of the substrate, three materials, namely nutrient soil, vermiculite, and ceramsite, are selected, which are mixed with the soil in different proportions to form different roof greening substrates. By measuring the indexes including the bulk density, water absorption rate, water loss rate, and hydraulic conductivity, the variation influence of material proportions on the physical properties of the substrates is analyzed.
Research and Design of Over - irrigation Control System for Underwater Pouring Concrete of Pile Foundation
Authors: Cao Zhen , Wei Yongbin
Published: February 2021

The quality of the pile head is the control difficulty of the concrete cast-in-situ pile technology when the bored piles, especially the deep foundation piles, are filled with underwater concrete. The hammer method and volume estimation method are widely used to control concrete over-irrigation height in the existing technology. However, in the actual operation, these two methods are inclined to cause mis-judgment by the field technicians, so it is difficult to accurately determine the over-irrigation height, resulting in the under-irrigation or the excessively high over-irrigation height of the pile head, which seriously affects the construction quality and greatly increase the cost of engineering costs. In order to solve this problem, combining modern sensing technology and communication technology, an over-irrigation height control system of underwater concrete cast-in-situ pile was developed in this paper based on the principle that the buoyancy changes at a certain depth due to the difference between the mud weight and the concrete proportion of the bored pile. The system is mainly composed of sensor based on Hall effect, data acquisition module, wireless communication module, remote network server and monitoring terminal, and serial tests were carried out. The test results show that the system can accurately monitor the concrete level to reach the pre-set height in advance, and timely alarm for overrun, and it is easy to operate and has high popularization value.
Removal of organic compounds from Microcystis aeruginosa by coagulants and its mechanisms
Authors: Xing Linan , Zheng Mingyue , Zhang Xiaohui , Lu Peng , Xie Guoli , Cao Qiguang , Chen Hongmei , Yang Dongqing
Published: February 2021

Algae organic matter (AOM) has always been a threat to the effective operation of water treatment processes. Coagulation is the most effective way to control the contamination. In this study, AlCl3, PAC and HPAC were investigated as the coagulants. The removal performances were considered by detecting TOC, turbidity, apparent molecular weight (AMW) and fluorescence excitation-emission matrix (FEEM). The turbidity and TOC removal rate can reach 95% when the optimal dosage of PAC and HPAC was 0.04 mol⋅L−1, respectively. For AlCl3, higher dosage is needed. HPAC has a good efficiency on small molecular weight compounds removal. Because there are active adsorption groups and the cationic groups in HPAC. These groups can make the make the AOM lose stability and flocculation through neutralization and adsorption bridging.
Influence of water injection parameters on fracturing effect in coal seam hydraulic fracturing
Authors: Li Liangwei
Published: February 2021

According to the basic parameters of Yangquan mining area, based on the determined meso physical and mechanical parameters and geological parameters, several groups of numerical calculation models considering different fracturing parameters (water injection flow and water injection time) are established. Then, the numerical simulation test of water injection fracturing is carried out by using the particle discrete element program, and the influence effect of related parameters of coal seam hydraulic fracturing is analyzed numerically, the influence of flow rate, pressure, time and other parameters on water injection flow is obtained.
Research Report on Technologies and Equipment for Exploitation of Marine Combustible Ice Resources
Authors: Jin Chaoyue
Published: February 2021

Scientists have been focusing on studying combustible ice as "new energy for the 21st century" due to its wide distribution, abundant reserves, high energy density, low pollution and other advantages. With boundless prospects, however, combustible ice has posed a severe challenge to the existing science and technology of human. Its exploitation technologies have become a key academic research field in the new century. Therefore, it is of vital importance to master scientific payoffs and development trends of Chinese domestic and foreign technologies and equipment for the exploitation of combustible ice and make breakthroughs in its drilling techniques in order to address the energy crisis and carry out the strategic action plan for energy development better in China.
Research on Optimal Utilization of Proven Undeveloped Gas Field
Authors: Zheng Likun
Published: February 2021

X gas field shows a large scale of proven unexploited reserves, however, most of them are characterized by low gas well production, rapid pressure decline, small well control reserves and poor economic benefits. How to economically and orderly develop and utilize these reserves is a difficult problem. By establishing an evaluation system for the existing developed blocks of X gas field, applying the method of multiple regression, establishing a comprehensive evaluation and scoring formula for development effect, taking the proven index data of the development block into the formula for calculating, the comprehensive evaluation score of development and utilization of un exploited reserves blocks, queuing the blocks with productivity and reserves in the new area.This method will provide technical reference for the next development and utilization of X gas field.
Carbon emission reduction cooperation in supply chain with government subsidies
Authors: Li Zhimin , Yang Wen , Pan Yanchun
Published: February 2021

Environmental sustainability has become the key index to evaluate the success of supply chain management. This paper aims at the problem of joint emission reduction in supply chain with government subsidies under the Cap-and-Trade mechanism(C&T). Three mathematical models considering green technology investment and two subsidy methods are constructed. It is found that government subsidies cannot ensure that enterprises reduce total carbon emissions. Compared with subsidies based on green investment costs, subsidies based on emission reduction have greater emission reductions, but the total carbon emissions are also greater.
Research on frequency Control Strategy of micro grid including wind power and hybrid energy storage system
Authors: Dong Xin , Wang Ruifeng
Published: February 2021

In view of the frequency fluctuation of the micro-grid system containing wind power, hybrid energy storage system composed of batteries and supercapacitors is adopted to coordinate the output, so as to maintain the frequency stability of the micro-grid and provide the possibility for the micro-grid to further absorb wind power and other clean energy. Firstly, by analyzing the characteristics of wind power output, the power deviation signal of the system is decomposed into low-frequency and high-frequency parts through wavelet packet decomposition, so as to maximize the consumption of wind power output power on the premise of meeting the stability of the system. Then, the high frequency part of the power gap is further divided to determine the initial FM power distribution scheme of the energy storage system. Finally, the energy storage output is modified by the Logistic regression function to take into account both the energy storage adaptive frequency modulation and the energy storage charged state self-recovery. Example analysis shows that the proposed control strategy can realize the optimal distribution of wind power, ensure the full utilization of wind farm output, improve wind power grid connection capacity, and increase efficiency and economy.
Research on the Framework of the New Urban Energy Internet Demonstration Project
Authors: Zhang Xiaoyan , Wang Hailong , Wang Bingwen , Huang Kun
Published: February 2021

Energy is the main driving force of economic development and social progress, and the relationship between its production and supply directly determines the destiny of the country. As to the new urban Energy Internet demonstration project, the characteristics and elements of the new urban Energy Internet are analyzed in this paper, and then the overall framework and information integration framework of the new urban Energy Internet demonstration project is proposed. Finally the overall framework and functional requirements of Energy Internet comprehensive management and service platform and the perception layer equipment are proposed, which can provide technical support and framework guidance for the development of new urban Energy Internet business.
Preliminary exploration of energy-saving residential design in hot summer and cold winter area taking Wuhan as an example
Authors: Hu Xueqing
Published: February 2021

In today's architectural design industry, building energy-saving design has become a hot topic, and it is a necessary link for the construction industry to implement sustainable development. However, most areas in China are in hot summer and cold winter. It is very meaningful to design energy-saving residential buildings in combination with the climate to make the buildings more livable and environmentally friendly. This paper demonstrates the design process of a small house in the suburbs of Wuhan, comprehensively considers the building shape, building natural lighting and ventilation, building maintenance structure, the actual application of new materials and new technologies for green house design. At the same time, it combines Ecotect and other computer technology to design the green house. The applied building energy saving technology is analyzed and optimized to provide new ideas for other related designs.
Headspace-Gas Chromatography Method for Determination of Formaldehyde Content in Wastewater
Authors: Xiao-long WANG , Lei ZHANG
Published: February 2021

Through the use of headspace-gas chromatography, the sensitivity and detection limit of formaldehyde content in wastewater obtained by the standard curve method and the standard addition method are compared in order to obtain the best detection method. The results show that the calibration curve correlation of the standard insertion method for testing the formaldehyde content in wastewater is 0.9991, the detection limit of the method is 0.18 mg/L, and the lower limit of determination is 0.69 mg/L. Excellent standard curve method; this method is used for samples with low, medium and high concentrations. The range of standard recovery rate calculated is 85.1%~112.9%, the relative standard deviation in the laboratory is 2.7%~ 6.3%, which is also better than the standard curve method and meets the test requirements. This method is easy to operate, high sensitivity, and low detection limit for the determination of formaldehyde in wastewater, which meets the requirements of analysis and testing.
Research on the Changes of Air Quality in Chengdu During the COVID-19 Pandemic
Authors: Deng Fumin , Zhang Hongjia , Ma Xiaolei , Liang Xuedong
Published: February 2021

As a public health emergency, COVID-19 has greatly affected all walks of life. It also has an impact on the environment. In order to systematically assess the impact of COVID-19 on the environment and the reasons for this impact, this paper takes Chengdu as an example for research. The air quality in Chengdu is analysed from two aspects of time and space, two dimensions of longitudinal and transverse. This paper selects six air pollution indexes (PM2.5, PM10, NO2, CO, SO2, O3)and applies the dual-weight fuzzy comprehensive evaluation method to analyse. The results show that, no matter what the angle is, the air quality in Chengdu has greatly improved during the COVID-19 blockade and the concentration of various pollutants has been greatly reduced. But it's worth thinking about that this situation is always temporary from a longitudinal perspective. With the unblocking and the restoration of industrial production, the air pollution situation begins to return to previous state. This paper provides a reference for studying the changes in air quality during the COVID-19 pandemic and provides a useful supplement for air pollution control.
Effects of magnetic particle proportion and additive amount on the extraction of Pb and Cd from soil by magnetic biochar
Authors: Gong Haofei , Tan Mingxia , Xing Haiwen , Huang Jianjun , Chi Jie
Published: February 2021

Due to the high sorption capacity for heavy metals, magnetic biochar (MBC) has the potential to adsorb heavy metals in soils, which are then removed together with MBC from soils by a magnetic field. However, little research on the magnetic particle (MP) proportion and the addition amount of MBC. In this study, different magnetic particle proportion and addition amount of MBC were evaluated by a batch experiment. The most suitable MP proportion of MBC was 0.2 mol/L Fe2+, under this MP proportion, the extraction rates of Pb and Cd were 42.9% and 37.2%, respectively. The most suitable addition amount was 2.5% under low pollution condition, and 7.5% under severe pollution condition.
Optimization Analysis of System and Air Distribution for Solar and Heat Pump Multi-energy Complementary Zanthoxylum Drying
Authors: Xue Hanling , Wan Xuening , Wu Yehao , Yan Yuting
Published: February 2021

Crops have high moisture content and are easily deteriorated, requiring dry storage. However, the drying energy consumption is relatively large and the drying quality of materials is often affected by the uneven distribution of indoor airflow. Author takes Zanthoxylumas for an example and designs two solar and heat pump drying systems in which the heat pump evaporator and the heat pipe are used to recover the waste heat respectively. The energy efficiency is compared and analyzed, the result shows that when the heat evaporator is used to recover the waste heat, the energy efficiency is higher and COP of the heat pump can reach 4.06. Based on the optimized system, the FLUENT software is used to simulate the airflow organization of the two types that supplying below and returning upward, and the side-supplying and side-returning. The results show that the airflow in the drying chamber has better uniformity when using the side-supplying and side-returning, which satisfies the requirements of Zanthoxylum drying.
Research on the Influence of Environmental Regulation on Enterprise Green Innovation Performance
Authors: Wang GuLei
Published: February 2021

according to summarizing the research status of environmental regulation, expected economic benefits of green innovation and enterprise green innovation per -formance at home and abroad, this paper discusses: (1) the affect of different types of regulation on green innovation performance, and divides environmental regulation into command control type, market incentive type and voluntary disclosure type, and discusses which way of environmental regulation can improve enterprise green innovation performance more effectively; (2) Taking the expected economy of green innovation as an intermediary variable, this paper discusses its intermediary mechanism between environment and enterprise green innovation performance; (3) Divide enterprise green innovation performance into two dimensions: economic performance and environmental performance, and analyze the effect of different kinds of environmental regulations on different dimensions of enterprise innovation performance.
Review on Plants Selection and Application Effects in Ecological Floating Beds based on Water purification
Authors: Zhang Haixia , Han Jianqiu , Chen Fengzhen , Yuan Qingqing
Published: February 2021

Due to the variety of plants and different types of polluted water quality, there is no unified standard for the application types of floating bed plants. Therefore, this paper summarizes and analyses 815 articles related to "ecological floating bed" and "plant water purification" that have been screened and identified in the search results of CNKI. According to plant types and water quality types, the purification effects of floating bed plants on different pollutants are comprehensively described to comprehensively evaluate the actual effects of plants in floating bed applications, which provides a useful scientific reference for the reader to screen and apply the plant in the floating bed.
Calculation of Carbon Emission During Expressway Operation Period Based on Energy Consumption Analysis
Authors: Chen Jie , Yu Zhonghui , Chen Guoyan , Zheng Yadong
Published: February 2021

This article divides the activities during the expressway operation period and analyzes its energy consumption. Based on the carbon emission coefficient method, a carbon emission calculation model is constructed to calculate carbon dioxide emissions. Studies have shown that the carbon emissions from highway infrastructure operations are the highest, and most of them are from electricity. Therefore, the application of energy saving and emission reduction technologies in infrastructure operations is essential.
Structural system selection and design of Zhangzhou Opera House Fujian Province
Authors: Yang Songlin , Ren Qingying , Liu Wenting , Zhang Xiaomeng
Published: February 2021

Zhangzhou Opera House adopts the complex structure system of petal shape. According to the building shape and architectural layout, the structure combines the steel truss for large-span space and the frame-shear wall structure surrounding. This article introduced its structural system, multi-line defense line arrangement and anti-seismic performance objectives, and summarized the structural characteristics of the overall structure, especially focusing on key issues such as setting the ring floor beam to resist the extroversive forces, anti-seismic performance of key components and the design of the junction between the steel truss and concrete structure. The results show that the structure has strong adaptability to the building shape with suitable seismic performance, and fulfilling both the requirements of seismic performance design and the structural safety.
Hydrological Simulation of Wohushan Reservoir Basin Based on NAM Model
Authors: Zhao Jiazhen , Cao Fangjing , Wang Jianguang , Li Taili
Published: February 2021

Based on the NAM model, a hydrological model of the Wohushan Reservoir was constructed. The rainfall and runoff process of the Wohushan Reservoir was simulated. The model was calibrated with 6 measured floods, and the model was verified by 6 measured floods.. The result showed that the qualified rate of the simulation results of the model was 83.3%, which reached the standard of the qualified rate of the model. In the flood simulation that meets the qualification requirements, the maximum error between the measured and simulated flood peaks is 14.248% and the minimum error is 10.001%; the maximum error between the measured and simulated flood peaks during the verification period is 12.376% and the minimum is 5.392%. The fitting of the measured flow process is relatively ideal and has certain practical significance.
Stability analysis of heterogeneous slope with concealed fault zone
Authors: Li Shulin , Chen Xinxin , Duan Jinqi , Li Tianjiao , Sun Xiangrui
Published: February 2021

Combined with the heterogeneous slope of the concealed fault zone at the dam site of a hydropower station in Nujiang River, a numerical analysis model is established by FLAC3D to study the influence of the content of fault gouge and fault breccia in the concealed fault zone on the stability of the slope. The results show that the safety factor increases linearly with the increase of internal friction angle when the cohesion is fixed, and linearly with the increase of cohesion when the internal friction angle is fixed. The variation of safety factor of internal friction angle is greater than that of cohesion. If the content of fault breccia is high, the safety factor is high. If the content of fault gouge is high, the safety factor is low.Comprehensive safety factor of concealed fault zone of local strength reduction method is basically consistent with that of FLAC3D concealed fault zone, and the heterogeneous slope is basically in a stable state.
Influence of Outdoor Wind Environment on Thermal Environment Around Rural Houses
Authors: Chang-fa JI , Huan ZHANG , Ying FU
Published: February 2021

According to statistics, building energy consumption accounts for 33% of the country's total energy consumption, in which rural building energy consumption accounts for 20%, and with the continuous advancement of new rural construction, various policies to benefit the people have been promulgated successively, this proportion will increase year by year.However, at present, the focus of building energy conservation work is concentrated in urban areas. Rural houses lack technical guidance on energy conservation in buildings. The self-built model is basically adopted, which consumes too much energy. Therefore, based on the CFD numerical simulation technology, this paper takes some rural houses in Xi'an as a research object, simulates its outdoor wind environment, combined with the wind environment evaluation standard, the existing problems of rural houses are analyzed, and the improvement scheme is proposed. After the adjustment, the simulation analysis again showed that when the angle between the rural house building and the wind direction in Xi'an is 45 °, the comfort of human living environment is the best, which provides a reference for future energy conservation and consumption reduction in rural areas.
Investigation and Research on the Treatment of Air Pollution by Heating Boiler of Beijing University of Chemical Technology
Authors: Yang Yuhua , Zhang Fan , Yang Shuya
Published: February 2021

On June 10, 2015, Beijing Municipal Environmental Protection Bureau issued “Boiler Atmospheric Pollutant Emission Standard” DB11/139-2015. Starting from April 1, 2017, NOx emissions from newly built boilers must be below 30mg/m3 and from in-use boilers must be below 80mg/m3. For implementing the emission reduction work in Beijing, according to current situation of boiler room in Beijing University of Chemical Technology, the school authorities do a series of work, including visits, market research and data analysis, attend academic conferences. On how to deal with the problem of air pollutant discharge standard of boilers in our university, we analyse the relevant emission standards at home and abroad, pollution prevention and control technology, low-nitrogen combustion principle of gas-fired industrial boilers and its technical development status, and put forward three solutions[1][2]. Through the comparison of advantages and disadvantages, the optimal solution is obtained.
Analysis on load distribution of beam-arch combination system bridge
Authors: Huang Huanzi , Yang Kun
Published: February 2021

Many prestressed concrete beam-arch combination system bridges have been built in China, but the research on the mechanical characteristics of beam-arch combination system bridges is insufficient. By adopting the structural mechanics and taking the three-span continuous beam-arch combination bridge as the research object, a theoretical formula for calculating the load distribution of the beam, arch and boom of the beam-arch combination system is put forward. By comparing the theoretical calculation with the finite element calculation, the theoretical calculation formula is verified, and the factors affecting the load sharing ratio and the bending moment distribution ratio are analysed. The results show that the load sharing ratio is less affected by the beam-arch bending stiffness ratio, and more affected by beam-to-boom equivalent stiffness ratio. The load sharing ratio increases with the increase of rise-span ratio and the decrease of side-to-span ratio. The beam-arch bending moment distribution ratio is related to the beam-arch bending stiffness ratio, the side-to-span ratio and the rise-span ratio, and beam-to-boom equivalent stiffness ratio.
ZnO nanorods alloyed with Mo/Er. The effect of post-deposition treatment on defect states and luminescence
Authors: Buryi M , Remeš Z , Babin V , Vaněček V , Aubrechtová Dragounová K , Mičová J , Landová L , Kučerková R
Published: February 2021

Free-standing ZnO nanorods alloyed with Er/Mo were synthesized by the hydrothermal growth method. To characterize them, the number of experimental techniques was applied including X-ray diffraction (XRD), scanning emission microscopy (SEM), electron paramagnetic resonance (EPR), photo- and radioluminescence (PL, RL). EPR confirmed the existence of F+centres common for ZnO-based structures in the ZnO:Er(30%) nanorods whereas in the ZnO:Mo(30%) this kind of defect was absent. Air annealing at elevated temperatures results in the reduction of F+centres in all the materials studied. Moreover, Er3+EPR signal also undergoes changes including broadening in the ZnO:Er. This allowed suggesting oxidation of Er ions on the ZnO nanorods surface. Red luminescence (~680 nm) appears in all studied samples regardless the dopant origin and doping level after the annealing in air. The exciton-related band at 380 nm never observed in the samples before the annealing appears upon the annealing at 350 °C in ZnO:Mo(10%) and ZnO:Er(30%). No such band was observed in the ZnO:Mo(30%) sample under the same conditions. According to SEM there are nanorods no more but microrods upon the content of Mo/Er as compared to the as-grown untreated ZnO as reported in a recent work.
Effect of ZnO nanoparticle sizes and illumination on growth inhibition of Escherichia coli and Staphylococcus aureus bacteria in cultivation medium
Authors: Jíra J , Rutherford D , Mičová J , Remeš Z , Rezek B
Published: February 2021

We study antibacterial effects of the zinc oxide nanoparticles (ZnO NPs) in cultivation medium (Mueller-Hinton broth) on Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria models. We compare synthesized ZnO hedgehog NPs and commercial ZnO NPs (50 nm and 20 μm nominal size) in different concentrations (1 mg/mL and 0.1 mg/mL). Results show that E. coli are more sensitive to the ZnO presence in the cultivation media than S. aureus. We also characterize influence of visible and UV light on the ZnO NP effects.
Age-varying Bi-directional Associations Between Momentary Affect and Movement Behaviors in Children: Evidence From a Multi-wave Ecological Momentary Assessment Study
Authors: Yang Chih-Hsiang , Zink Jennifer , Belcher Britni R , Kanning Martina , Dunton Genevieve F
Published: February 2021

Background

The bi-directional associations between affective states and movement behaviors (e.g., physical activity, sedentary behavior) have been observed in children. It is unclear if the strength of these bi-directional associations varies with age as children transition from childhood to adolescence.

Purpose

This multi-wave ecological momentary assessment (EMA) study investigates the acute time-varying associations between affect and movement behaviors among youth.

Methods

Children (N = 195, baseline mean age = 10.72, range = 8–12 years, mean BMI-z = 0.49, 51% female) participated in a six-wave EMA study across three years. Each EMA survey captured momentary positive and negative affect. Time spent in moderate-to-vigorous physical activity (MVPA) and sedentary time in the 15-min window before and after each EMA survey was calculated using accelerometry data. Time-varying effect models (TVEM) examined the acute bi-directional associations between momentary positive/negative affect and MVPA/sedentary time across ages 8 to 14.

Results

Children provided 14,246 valid activity-matched EMA surveys across all waves. TVEM plots revealed that the directionality and the strength (time-varying slopes) of associations between momentary affect and activity levels vary across ages. Positive affect was associated with higher MVPA levels and lower sedentary time at younger ages, whereas negative affect linked to lower MVPA levels and more sedentary time at older ages.

Conclusions

The acute associations between momentary affect and (in)activity levels may vary as a function of children's age. Applying TVEM to intensive longitudinal data could provide valuable information for developing age-tailored interventions that promote healthy lifestyles among children and adolescents.
Recovery of the Decline in Activities of Daily Living After Hospitalization Through an Individualized Exercise Program: Secondary Analysis of a Randomized Clinical Trial
Authors: Martínez-Velilla Nicolás , Sáez de Asteasu Mikel L , Ramírez-Vélez Robinson , Zambom-Ferraresi Fabricio , García-Hermoso Antonio , Izquierdo Mikel
Published: February 2021

Background

During the period of hospitalization, patients can develop functional decline. The main aim of our study was to assess the natural trajectory of each activity of daily living (ADL) and to assess how in-hospital exercise could influence short-term trajectory of ADLs.

Method

Acutely hospitalized patients (n = 297, 56.5% women) were randomly assigned to the intervention or control (usual care) group within the first 48 hours of admission. An exercise training program was prescribed in 2 daily sessions (morning and evening) of 20 minutes duration during 5–7 consecutive days for the intervention group. The primary endpoint was the change in every ADL (assessed with the Barthel Index) from 2 weeks before admission to hospital discharge.

Results

Acute hospitalization per se led to significant in-patient’s functional ability impairment in ADLs during hospitalization, whereas the exercise intervention reversed this trend (3.7 points; 95% CI: 0.5–6.8 points). After analyzing the trajectory of each one of the ADLs, patients in the control group significantly worsened all activities, but with a different degree of loss. For the between-group analysis, significant differences were obtained in many ADLs including bathing, dressing, grooming, bladder control, toilet use, transfers, mobility, and climbing stairs (p < .05). The control group had the greatest impairment in all domains analyzed (ie, feeding, bathing, dressing, grooming, bowel control, bladder control, toilet use, transfers, mobility, and climbing stairs; p < .05).

Conclusions

An individualized multicomponent exercise training program in older adults is effective to reverse the loss of specific ADLs that frequently occurs during hospitalization. Each patient profile should receive an individualized prescription of exercise during hospitalizations.

Clinical Trials Registration Number

NCT02300896.
Associations of Salivary Total Antioxidant Capacity With Cortical Amyloid-Beta Burden, Cortical Glucose Uptake, and Cognitive Function in Normal Aging
Authors: Palomar-Bonet Miriam , Atienza Mercedes , Hernández-Ledesma Blanca , Cantero Jose L
Published: February 2021

Background

Determining susceptibility to Alzheimer’s disease (AD) in asymptomatic individuals requires from noninvasive, simple, and inexpensive markers that can be easily obtained in primary care settings. While saliva meets all these requirements, there is a lack of evidence linking salivary constituents to in vivo AD pathology in aging.

Methods

We examined the potential of salivary total antioxidant capacity (TAC) for identifying global cortical amyloid-beta (Aβ) burden, deficits in regional glucose uptake, and poorer cognition in 71 cognitively normal older adults. We further assessed whether salivary TAC-related cognitive performance was associated with higher Aβ load and lower cortical glucose consumption.

Results

Linear regression analyses adjusted by age, sex, years of education, and ApoE4 status showed that salivary TAC was associated with slower processing speed and poorer sustained attention, as well as with higher Aβ load and lower glucose metabolism in cortical regions vulnerable to cognitive aging and AD. Results also revealed that lower scores in processing speed and sustained attention were associated with greater Aβ burden and lower regional glucose consumption, respectively.

Conclusions

Together, these findings support the use of salivary TAC for preventive screening and detection of cerebral vulnerability to AD. Further research is needed to evaluate the utility of salivary TAC as a clinical marker.
Tobacco Use and Cessation
Authors: Brandon Thomas H. , Simmons Vani N. , Martínez Úrsula , Calixte-Civil Patricia
Published: February 2021

Tobacco use, particularly cigarette smoking, continues to be the leading preventable cause of cancer. Moreover, smoking by cancer patients is detrimental to their treatment outcomes and prognosis. Therefore, tobacco control remains a key element of comprehensive cancer prevention and control. The tobacco landscape continues to evolve, with demographic shifts in tobacco use exacerbating existing health disparities, while the emergence of electronic cigarettes presents both opportunities and challenges. This chapter summarizes these ongoing changes and then provides an overview of both pharmacological and behavioral smoking cessation strategies. With respect to cancer patients, as the benefits of smoking cessation have been identified, there have been accumulating recommendations and guidelines for the systematic assessment and treatment of tobacco use.
Cervical Cancer Screening and HPV Vaccination
Authors: Fielding Richard , Perez Samara , Rosberger Zeev , Tatar Ovidiu , Wang Linda D. L.
Published: February 2021

Cervical cancer kills 300,000 women annually, despite being among the most preventable of all cancers, with a well-known cause (human papilloma virus [HPV]), established and successful screening strategies, and effective vaccination and treatments. This chapter examines the reasons for this inconsistency and begins by outlining the epidemiology and public health burden of cervical cancers. It describes HPV vaccine–related successes and challenges in low- and middle-income countries contrasted with high-income countries, with emphasis on the two most populous countries of India and China, before examining issues around strategies for cervical cancer screening in high- and low-resource settings. Following discussion of screening recommendations, the chapter describes barriers and facilitators to vaccination, screening, and testing. It then addresses screening and vaccination messaging and the psychological impact of testing and concludes with future directions.
Breast Cancer Screening
Authors: Leung Gabriel M. , Wong Irene O. L. , Kwong Ava , Wu Joseph T.
Published: February 2021

Mammography has been deployed to screen for early breast cancer since the 1980s. Its use has recently and increasingly been called into question in populations with long-established programs, as well as in emerging economies. The biology of breast carcinogenesis differs from those of other cancers amenable to screening in that there is no obligate precursor state. The available screening modalities yield a significant proportion of false positives, thus negatively affecting the benefit-to-harm tradeoff. Future efforts should focus on improving pretest risk stratification, considering new noninvasive adjunct technologies to reduce the need for invasive confirmatory procedures, and incorporating the risk preferences of individual women toward precision screening.
Lung Cancer Screening
Authors: Carter-Harris Lisa , Ostroff Jamie
Published: February 2021

Lung cancer is the deadliest cancer worldwide. Screening with low-dose computed tomography of the chest is still new and many screening-eligible individuals are unaware of this screening option, contributing to the extremely low rates of screening uptake. This chapter discusses the psychosocial influences on lung cancer screening behavior from the perspective of the individual making the decision to screen, or not, for lung cancer. It also discusses key topics such as integrating smoking cessation into the lung cancer screening setting, shared decision-making in the context of lung cancer screening, and future research needed in this nascent area of cancer screening.
Psychosocial Issues in Genetic Testing for Breast/Ovarian Cancer
Authors: Esplen Mary Jane , Hunter Jonathan , Bleiker Eveline M. A.
Published: February 2021

Approximately 10% of all breast cancers are due to hereditary factors, with the majority caused by mutations in two autosomal dominant breast cancer genes, BRCA1 and BRCA2. Mutations in these genes are associated with cumulative risks of breast cancer of 72% in BRCA1 mutation carriers and 69% in BRCA2 mutation carriers by age 80. Mutation carriers who develop breast cancer have elevated risk for contralateral breast cancer. BRCA1/2 mutations also place women at elevated risk for ovarian cancer. Genetic counseling and testing are available to individuals, with or without cancer, to inform health-related decision-making. While genetic knowledge offers opportunities for prevention, including prophylactic risk-reducing surgery, a number of psychological and social challenges have been identified in the BRCA1/2 population. This chapter provides a broad overview of seminal research on the psychosocial impacts of genetic testing in BRCA1/2 with the goal of helping readers better identify, evaluate, and treat psychosocial challenges stemming from the process of genetic testing. Identifiable risk factors for psychosocial distress during the genetic counseling process are summarized. The chapter points toward key psychometric instruments designed to support psychosocial screening in cancer genetic populations. Further, a summary of intervention strategies to support psychosocial adaptation to genetic testing is provided.
Screening for Delirium and Dementia in the Cancer Patient
Authors: Bjerre-Real Christian , Root James C. , Alici Yesne , Kearney Julia A. , Breitbart William S.
Published: February 2021

Cognitive syndromes are commonly encountered among cancer patients. Although aging is an important risk factor for cognitive disorders, in oncology settings there are additional risk factors, including primary or metastatic brain tumors, medical comorbidities, cancer treatments, and depression, that place all age groups at risk for cognitive syndromes. Delirium, a common cognitive syndrome among hospitalized cancer patients, has been shown to increase risk of long-term cognitive impairment. Dementia is a risk factor for delirium development as well. Patients with cognitive deficits may not be able to carry out activities of daily living, such as medication maintenance, food preparation, and transportation. Treatment adherence, vigilance in monitoring and reporting of cancer and cancer treatment–related symptoms, and the ability to make informed decisions on cancer treatment options necessitate intact cognitive functioning. Therefore, screening for cognitive syndromes among cancer patients is an important part of initial assessment, particularly in high-risk populations. This chapter will provide a comprehensive review of the screening and assessment measures used to identify and assess patients with delirium and dementia. A brief overview of common dementia syndromes is also included as relevant to psycho-oncologists caring for older adults with cancer.
Screening and Assessment for Cognitive Problems
Authors: Gaynor Alexandra M. , Root James C. , Ryan Elizabeth , Ahles Tim A.
Published: February 2021

Cancer-associated cognitive dysfunction (CACD) is experienced by up to two-thirds of cancer survivors and may persist for decades following completion of treatment. Cognitive dysfunction in survivors may be subtle and may impact performance in or more cognitive domains; therefore, there is a need for objective measures of function that have adequate sensitivity and specificity to detect cognitive decline in this population. This chapter discusses brief cognitive screening measures and their utility in detecting dysfunction, as well as more comprehensive flexible neuropsychological assessment measures and their use in cancer survivors. The chapter provides a review of research examining the sensitivity and specificity of these measures in the detection of CACD, as well as their effect on patient outcomes, and provides recommendations for future research and the use of flexible neuropsychological assessment batteries in the screening and assessment of CACD.
Gastrointestinal Cancers
Authors: McFarland Daniel C. , Breitbart William S.
Published: February 2021

Gastrointestinal (GI) cancers that originate from outside the colon and rectum are common and distressing for reasons distinct from colorectal cancer. The GI tract includes the uniquely contributory organ functionality of the pancreas, liver, and stomach, which manifest as distinct cancer types with unique morbidity associations. While digestion is certainly the primary quality-of-life issue that is disrupted during the cancer experience and trajectory, there are various other important quality-of-life issues to consider. Unfortunately, these noncolorectal GI cancers tend to carry a worse overall prognosis and the morbidity is greatly influenced by cancer type, anatomic location, and treatment regimen (local and systemic). Pancreatic, esophageal, gastric, and hepatobiliary cancers affect digestion, nutrient absorption, and weight management and can cause significant pain and other physical morbidity such as edematous states. Aside from the stress of physical morbidity or unique treatment side effects, pancreatic cancer has a unique relationship with depression that should be explored for its biological implications in causing depressive symptoms. In addition, patients may be distressed by the novelty or rarity of many of these noncolorectal GI cancers (e.g., cholangiocarcinoma) that may fall into an orphan disease category without well-studied treatment paradigms. Understanding the key characteristics of the primary types of noncolorectal GI cancers (i.e., pancreatic, gastric, esophageal, and hepatobiliary cancers) allows the psycho-oncology clinician to approach these patients with appropriate concern and caring for the primary issues with which they are toiling.