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Author(s):  
C. Song ◽  
Y. Wang ◽  
J.Y. Liu ◽  
F. Zhao ◽  
X.R. Huang ◽  
...  

Background: Temperature is one of the most important environmental factors affecting the survival, growth and metabolism of fish. The current study was aimed to study the effects of water temperature on the metabolic enzyme activities of juvenile Siganus guttatus. Methods: The juveniles were domesticated at 28±1°C for two weeks and then the temperature was adjusted to the target temperature groups (31°C, 27°C, 23°C and 19°C) by the gradually increasing or decreasing temperature with the change rate of 2°C per day. The experiment lasted for 70 d. At the end of the experiment, the fish were anesthetized and all the livers were dissected on ice plate and stored in the refrigerator at -80°C for the determination of enzyme activity. Result: The activities of glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT), hexokinase (HK) and pyruvate kinase (PK), lipoprotein lipase (LPL) and hepatic lipase (HL) tend to be increased with the reduction of temperature. The above enzymes activities in 19°C group were highest. The activity of lactate dehydrogenase (LDH), succinate dehydrogenase (SDH) and citrate synthase (CS) was lowest in 19°C. These results suggests that 19°C had exceeded the suitable temperature range for juvenile S. guttatus. At low temperature, S. guttatus mainly use fat for energy, but less anaerobic metabolism for energy.


Coatings ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 96
Author(s):  
Yung-Lin Chen ◽  
Yi-Cheng Lin ◽  
Wan-Yu Wu

It has always been a huge challenge to prepare the Mo back contact of inorganic compound thin film solar cells (e.g., CIGS, CZTS, Sb2Se3) with good conductivity and adhesion at the same time. High-power impulse magnetron sputtering (HiPIMS) has been proposed as one solution to improve the properties of the thin film. In this study, the HiPIMS technology replaced the traditional DC power sputtering technology to deposit Mo back contact on polyimide (PI) substrates by adjusting the experimental parameters of HiPIMS, including working pressure and pulse DC bias. When the Mo back contact is prepared under a working pressure of 5 mTorr and bias voltage of −20 V, the conductivity of the Mo back contact is 9.9 × 10−6 Ωcm, the residual stress of 720 MPa, and the film still has good adhesion. Under the minimum radius of curvature of 10 mm, the resistivity change rate of Mo back contact does not increase by more than 15% regardless of the 1680 h or 1500 bending cycle tests, and the Mo film still has good adhesion in appearance. Experimental results show that, compared with traditional DC sputtering, HiPIMS coating technology has better conductivity and adhesion at the same time, and is especially suitable for PI substrates.


2022 ◽  
Author(s):  
Jonathan Pitchford ◽  
Kimberly Cressman ◽  
Julia A Cherry ◽  
Brook T Russell ◽  
Jay McIlwain ◽  
...  

Abstract The Grand Bay estuary is in the north-central Gulf of Mexico and lacks riverine sediment input for marsh elevation maintenance. This study quantified trends in surface elevation change and accretion along an elevation gradient within the estuary. Elevation change rates were compared to short (13.71 mm/yr; 95% CI: -2.38 – 29.81), medium (6.97 mm/yr; 95% CI: 3.31 – 10.64), and long-range (3.50 mm/yr; 95% CI: 2.88 – 4.11) water level rise (WLR) rates for the region. Elevation change rates ranged from 0.54 mm/yr (95% CI: -0.63 – 1.72) to 5.45 mm/yr (95% CI: 4.27 – 6.62) and accretion rates ranged from 0.82 mm/yr (95% CI: -0.16 – 1.80) to 3.89 mm/yr (95% CI: 2.90 – 4.89) among marsh zones. Only the elevation change rate at a Juncus roemerianus marsh located high in the tidal frame was lower than long- ( P <0.001) and medium-range WLR rates ( P <0.01). The elevation change rate at a lower elevation J. roemerianus marsh was higher than the long-range WLR rate ( P <0.05). No marsh zones had elevation change rates that were significantly different from short-range WLR. These results suggest that J. roemerianus marshes higher in the tidal frame with limited sediment delivery are the most vulnerable to increases in sea level. Lower elevation marshes had higher rates of elevation change driven by sediment accretion and biogenic inputs. Other local research suggests that shoreline erosion is a threat to marsh persistence but provides elevation capital to interior marshes. Marsh migration is potential solution for marsh persistence in this relatively undeveloped area of the Gulf Coast.


Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 102
Author(s):  
Baoping Xu ◽  
Yuekang Liu ◽  
Yanzhe Dou ◽  
Ling Hao ◽  
Xi Wang ◽  
...  

Material emission and ventilation are two aspects influencing indoor air quality. In this study, a model predictive control (MPC) strategy is proposed for intermittent ventilation system in office buildings, to achieve a healthy indoor environment. The strategy is based on a dynamic model for predicting emissions of volatile organic compounds (VOCs) from materials. The key parameters of formaldehyde from panel furniture in the model are obtained by an improved C-history method and large-scale chamber experiments. The effectiveness of the determined key parameters is validated, which are then used to predict the formaldehyde concentration variation and the pre-ventilation time in a typical office room. In addition, the influence of some main factors (i.e., vacant time, loading ratio, air change rate) on the pre-ventilation time is analyzed. Results indicate that the pre-ventilation time of the intermittent ventilation system ranges from several minutes to several hours. The pre-ventilation time decreases exponentially with the increase in the vacant time, the air change rate, and with the decrease in the loading ratio. When the loading ratio of the furniture is 0.30 m2/m3 and the vacant time is 100 days, the required pre-ventilation time approaches zero. Results further reveal that an air change rate of 2 h−1 is the most effective means for rapid removal of indoor formaldehyde for the cases studied. The proposed strategy should be helpful for achieving effective indoor pollution control.


2022 ◽  
Vol 14 (2) ◽  
pp. 262
Author(s):  
Hui Guo ◽  
Xiaoyan Wang ◽  
Zecheng Guo ◽  
Siyong Chen

Snow cover is an important water source and even an Essential Climate Variable (ECV) as defined by the World Meteorological Organization (WMO). Assessing snow phenology and its driving factors in Northeast China will help with comprehensively understanding the role of snow cover in regional water cycle and climate change. This study presents spatiotemporal variations in snow phenology and the relative importance of potential drivers, including climate, geography, and the normalized difference vegetation index (NDVI), based on the MODIS snow products across Northeast China from 2001 to 2018. The results indicated that the snow cover days (SCD), snow cover onset dates (SCOD) and snow cover end dates (SCED) all showed obvious latitudinal distribution characteristics. As the latitude gradually increases, SCD becomes longer, SCOD advances and SCED delays. Overall, there is a growing tendency in SCD and a delayed trend in SCED across time. The variations in snow phenology were driven by mean temperature, followed by latitude, while precipitation, aspect and slope all had little effect on the SCD, SCOD and SCED. With decreasing temperature, the SCD and SCED showed upward trends. The mean temperature has negatively correlation with SCD and SCED and positively correlation with SCOD. With increasing latitude, the change rate of the SCD, SCOD and SCED in the whole Northeast China were 10.20 d/degree, −3.82 d/degree and 5.41 d/degree, respectively, and the change rate of snow phenology in forested areas was lower than that in nonforested areas. At the same latitude, the snow phenology for different underlying surfaces varied greatly. The correlations between the snow phenology and NDVI were mainly positive, but weak correlations accounted for a large proportion.


2022 ◽  
Author(s):  
Jonathan Oberreuter ◽  
Edwin Badillo-Rivera ◽  
Edwin Loarte ◽  
Katy Medina ◽  
Alejo Cochachin ◽  
...  

Abstract. We present a representative set of data of interpreted ice thickness and ice surface elevation of the ablation area of the Artesonraju glacier between 2012 and 2020. The ice thickness was obtained by means of Ground Penetrating Radar (GPR), while the surface elevation was by means of automated total stations and mass balance stakes. The results from GPR data show a maximum depth of 235 ± 18 m and a decreasing mean depth ranging from 134 ± 18 m in 2013 to 110 ± 18 m in 2020. Additionally, we estimate a mean ice thickness change rate of −4.2 ± 3.2 m yr−1 between 2014 and 2020 with GPR data alone, which is in agreement with the elevation change in the same period. The latter was estimated with the more accurate surface elevation data, yielding a change rate of −3.2 ± 0.2 m yr−1, and hence, confirming a negative glacier mass balance. The data set can be valuable for further analysis when combined with other data types, and as input for glacier dynamics modeling, ice volume estimations, and GLOF (glacial lake outburst flood) risk assessment. The complete dataset is available at https://doi.org/10.5281/zenodo.5571081 (Oberreuter et al, 2021).


Nutrients ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 249
Author(s):  
Mana Hatanaka ◽  
Yoichi Hatamoto ◽  
Eri Tajiri ◽  
Naoyuki Matsumoto ◽  
Shigeho Tanaka ◽  
...  

Recent studies have reported that meal timing may play an important role in weight regulation, however it is unknown whether the timing of meals is related to the amount of weight loss. This study aimed to examine the relationship between indices of meal timing and weight loss during weight loss intervention in adults. A 12-week weight loss support program was conducted for 97 adults (age: 47.6 ± 8.3 years, BMI: 25.4 ± 3.7 kg/m2). After the program, body weight decreased by −3.0 ± 2.7%. Only the start of the eating window was positively correlated with the weight change rate in both sexes (men: r = 0.321, p = 0.022; women: r = 0.360, p = 0.014). The participants were divided into two groups based on the start of the eating window as follows: the early group (6:48 ± 0:21 AM) and the late group (8:11 ± 1:05 AM). The weight loss rate in the early group was significantly higher (−3.8 ± 2.7%) than that in the late group (−2.2 ± 2.5%). The present results showed that the start of the early eating window was associated with weight loss and suggested paying attention to meal timing when doing weight loss.


2022 ◽  
Vol 2022 ◽  
pp. 1-8
Author(s):  
Yuzhou Tang ◽  
Xiaodang Peng ◽  
Shiyong Xu ◽  
Mingju Bai ◽  
Lifang Lin ◽  
...  

In order to study the gaze behavior characteristics of drivers in mountainous road sections with limited sight distance, the real vehicle test is carried out by using Smart Eye Pro 5.7 noninvasive eye tracker. Combined with the sight distance change rate theory, 6 typical test representative mountainous sections are selected to study the gaze distribution law and gaze duration of drivers in different mountainous sections. The research shows that when the driver drives on the test section with the most unfavorable sight distance of 44 m, 50 m, and 56 m, the fixation characteristics of “from far to near” are significant, and the long fixation duration accounts for a large proportion of the driver. When the driver drives on the section with the most unfavorable sight distance of more than 70 m, i.e., the sight distance change rate of less than 1.33, the fixation characteristics of “from far to near” disappear. The driver’s fixation stability increases, the fixation freedom increases, and the proportion of medium and long fixation duration decreases. The data analysis provides a theoretical basis for drivers to pass safely in mountainous sections.


Author(s):  
Shivan Jumaa

In this study, we discuss the properties of absolute vacuum space and how these properties can play a vital role in creating a mechanism in which the very first particle gets created simultaneously everywhere and we find the limit in which when the absolute vacuum volume reaches will lead to the collapse that leads to the creation of the first particle. This discussion is made following to the elementary dimensions theory study that was peer-reviewed at the end of 2020, everything in the universe is made from four elementary dimensions, these dimensions are the three spatial dimensions (X, Y, and Z) and the Vacuum resistant as the factor of change among the four, time itself wasn&rsquo;t considered as the fourth dimension, rather time corresponds to a factor of change, and during the research it was found out that the Vacuum resistant is the factor of change in the Absolute Vacuum space, where time is a hypothetical concept, that represents changes during certain events compared to a constant change rate event.Therefore, time does exist, but as a factor of change, and as the Vacuum resistant in the absolute vacuum space, Time= factor of change= Vacuum resistant. In the study, the internal and external vacuum resistant volume equivalent is found, External Vacuum resistant=3.2857602*10^15 *mass. This equation is used to identify the amount of Free external vacuum resistant created during nuclear fission and fusion: Initial mass of the excited nucleuses mass of the created new nucleuses+ 3.2857602*10^15 * the lost Mass. In elementary dimensions, the energy created during nuclear reactions is equivalent to the free External vacuum resistant created through nuclear reactions, and mass is equivalent to the internal Vacuum resistant.


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