scholarly journals Does weather affect the growth rate of COVID-19, a study to comprehend transmission dynamics on human health

2020 ◽  
Author(s):  
Arjun Sil ◽  
Vanapalli Naveen Kumar
Keyword(s):  
Growth Rate ◽  
Transmission Rate ◽  
Environmental Parameters ◽  
Transmission Dynamics ◽  
Temperature Changes ◽  
Daily Rate ◽  
The Mean ◽  
Novel Coronavirus ◽  
Short Time ◽  
The Relationship

AbstractThe undefendable outbreak of novel coronavirus (SARS-COV-2) lead to a global health emergency due to its higher transmission rate and longer symptomatic duration, created a health surge in a short time. Since Nov 2019 the outbreak in China, the virus is spreading exponentially everywhere. The current study focuses on the relationship between environmental parameters and the growth rate of COVID-19. The statistical analysis suggests that the temperature changes retarded the growth rate and found that −6.28°C and +14.51°C temperature is the favorable range for COVID-19 growth. Gutenberg-Richter’s relationship is used to estimate the mean daily rate of exceedance of confirmed cases concerning the change in temperature. Temperature is the most influential parameter that reduces the growth at the rate of 13–16 cases/day with a 1°C rise in temperature.

scholarly journals The isotopic record at an alpine glacier and its implications for local climatic changes and isotopic homogenization processes

2001 ◽  
Vol 47 (156) ◽  
pp. 147-151 ◽  
Author(s):  
He Yuanqing ◽  
Wilfred H. Theakstone ◽  
Yao Tandong ◽  
Shi Yafeng
Keyword(s):  
Equilibrium Line Altitude ◽  
Temperature Variations ◽  
Alpine Glacier ◽  
Temperature Changes ◽  
Natural Factors ◽  
Air Temperatures ◽  
Regional Temperature ◽  
The Mean ◽  
A Site ◽  
The Relationship

AbstractStratigraphic variations of oxygen isotopes in the snow which accumulates during the winter at the Norwegian glacier Austre Okstindbreen are not entirely eliminated after 1–2 months of ablation in the following summer. The relationship between regional temperature changes and δ18O values in the snowpack is affected by many natural factors, but 1989/90 winter air temperatures were reflected in the snow which remained on Austre Okstindbreen at 1350 m a.s.l. in July 1990. There were many variations of δ18O values in the 4.1m of snow above the 1989 summer surface, but variations in the underlying firn were relatively small. Meltwater percolation modifies the initial variations of δ18O values in the snowpack. At a site below the mean equilibrium-line altitude on Austre Okstindbreen, increased isotopic homogenization within a 10 day period in July accompanied an increase of the mean δ18O value. Although the isotopic record at a temperate glacier is likely to be influenced by more factors than is that at polar glaciers, it can provide an estimate of the approximate trend of local temperature variations.

scholarly journals Thermal Time Constant of PV Roof Tiles Working under Different Conditions

2019 ◽  
Vol 9 (8) ◽  
pp. 1626 ◽  
Author(s):  
Kurz ◽  
Nawrowski
Keyword(s):  
Energy Balance ◽  
Thermal Resistance ◽  
Temperature Change ◽  
Environmental Parameters ◽  
Thermal Capacity ◽  
Electrical Characteristics ◽  
Legal Regulations ◽  
Temperature Changes ◽  
Different Types ◽  
The Relationship

This paper presents different types of photovoltaic (PV) roof tiles integrating PV cells with roof covering. Selected elastic photovoltaic roof tiles were characterised for their material and electrical characteristics. Practical aspects of using PV roof tiles are discussed, alongside the benefits and drawbacks of their installation on the roof. Thermal resistance, heat transfer coefficient and thermal capacity were identified for elastic PV roof tiles and roof construction built of boards and PV roof tiles, according to valid standards and legal regulations. The resistance–capacity (RC) models of PV roof tiles and roofs are proposed according to the time constants identified for the analysed systems. The energy balance of the studied systems (PV roof tiles alone and the roof as a whole) is presented, based on which temperature changes in the PV cells of the roof tiles working under different environmental conditions were identified. The timing of PV cells’ temperature change obtained by material data and energy balance analyses were compared. The relationship between the temperature change times of PV cells and the thermal resistance and heat capacity of the whole system are demonstrated, alongside environmental parameters.

scholarly journals Modeling the Novel Coronavirus (SARS-CoV-2) Outbreak in Sicily, Italy

2020 ◽  
Vol 17 (14) ◽  
pp. 4964 ◽  
Author(s):  
Andrea Maugeri ◽  
Martina Barchitta ◽  
Sebastiano Battiato ◽  
Antonella Agodi
Keyword(s):  
Transmission Rate ◽  
Control Measures ◽  
Transmission Dynamics ◽  
The Novel ◽  
Epidemic Spread ◽  
Transmission Rates ◽  
Contact Precautions ◽  
Travel Restrictions ◽  
Novel Coronavirus ◽  
Reported Data

Italy was the first country in Europe which imposed control measures of travel restrictions, quarantine and contact precautions to tackle the epidemic spread of the novel coronavirus (SARS-CoV-2) in all its regions. While such efforts are still ongoing, uncertainties regarding SARS-CoV-2 transmissibility and ascertainment of cases make it difficult to evaluate the effectiveness of restrictions. Here, we employed a Susceptible-Exposed-Infectious-Recovered-Dead (SEIRD) model to assess SARS-CoV-2 transmission dynamics, working on the number of reported patients in intensive care unit (ICU) and deaths in Sicily (Italy), from 24 February to 13 April. Overall, we obtained a good fit between estimated and reported data, with a fraction of unreported SARS-CoV-2 cases (18.4%; 95%CI = 0–34.0%) before 10 March lockdown. Interestingly, we estimated that transmission rate in the community was reduced by 32% (95%CI = 23–42%) after the first set of restrictions, and by 80% (95%CI = 70–89%) after those adopted on 23 March. Thus, our estimates delineated the characteristics of SARS-CoV2 epidemic before restrictions taking into account unreported data. Moreover, our findings suggested that transmission rates were reduced after the adoption of control measures. However, we cannot evaluate whether part of this reduction might be attributable to other unmeasured factors, and hence further research and more accurate data are needed to understand the extent to which restrictions contributed to the epidemic control.

Growth rate and growth composition of artificially reared piglets from specific pathogen free sows

1993 ◽  
Vol 56 (2) ◽  
pp. 217-223 ◽  
Author(s):  
M. W. A. Verstegen ◽  
W. van der Hel ◽  
F. J. M. Pijls
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Nitrogen Balance ◽  
Environmental Temperature ◽  
Specific Pathogen Free ◽  
Protein Deposition ◽  
Daily Rate ◽  
Specific Pathogen ◽  
Balance Technique ◽  
The Mean

AbstractHeat production, energy and nitrogen balances of artificially reared piglets from specific pathogen free sows, housed in a respiratory chamber, were measured over five successive periods of 7 days each from 4 to 39 days of age. The experiment was carried out at an environmental temperature decreasing from 33 to 27°C. The mean weight increased from 1·5 (at day 4) to 11·9 kg (at day 39). Daily rate of gain increased from about 100 g in periods 1 and 2 to 502 g per piglet in the fifth period.Daily protein deposition, as measured via nitrogen balance, increased from 17 to 96 g; fat deposition increased from about 0 to 100 g. Body composition at the start and end was determined by a comparative slaughter technique. Protein and fat content had a high correlation coefficient with body weight (R2 = 0·69 and 0·89, respectively). At birth these values were much lower, 0·24 and 0·01 for protein and fat, respectively.Nitrogen balance compared with slaughter technique led to an overestimation for protein deposition of proportionately 0·07. Fat gain measured from slaughter was proportionately 0·08 lower than that calculated from energy balance.Ratio of gain estimated from protein and fat gain with the balance technique relative to that measured ranged between 0·93 to 1·15 in various periods.

scholarly journals Global COVID-19 transmission rate is influenced by precipitation seasonality and the speed of climate temperature warming

2020 ◽  
Author(s):  
Katsumi Chiyomaru ◽  
Kazuhiro Takemoto
Keyword(s):  
Growth Rate ◽  
Transmission Rate ◽  
Global Climate ◽  
Human Life ◽  
Life Quality ◽  
Lower Growth ◽  
Climate Parameters ◽  
Precipitation Seasonality ◽  
Travel Restrictions ◽  
Novel Coronavirus

AbstractThe novel coronavirus disease 2019 (COVID-19) became a rapidly spreading worldwide epidemic; thus, it is a global priority to reduce the speed of the epidemic spreading. Several studies predicted that high temperature and humidity could reduce COVID-19 transmission. However, exceptions exist to this observation, further thorough examinations are thus needed for their confirmation. In this study, therefore, we used a global dataset of COVID-19 cases and global climate databases and comprehensively investigated how climate parameters could contribute to the growth rate of COVID-19 cases while statistically controlling for potential confounding effects using spatial analysis. We also confirmed that the growth rate decreased with the temperature; however, the growth rate was affected by precipitation seasonality and warming velocity rather than temperature. In particular, a lower growth rate was observed for a higher precipitation seasonality and lower warming velocity. These effects were independent of population density, human life quality, and travel restrictions. The results indicate that the temperature effect is less important compared to these intrinsic climate characteristics, which might thus be useful for explaining the exceptions. However, the contributions of the climate parameters to the growth rate were moderate; rather, the contribution of travel restrictions in each country was more significant. Although our findings are preliminary owing to data-analysis limitations, they may be helpful when predicting COVID-19 transmission.

scholarly journals Transmission potential of the novel coronavirus (COVID-19) onboard the Diamond Princess Cruises Ship, 2020

2020 ◽  
Author(s):  
Kenji Mizumoto ◽  
Gerardo Chowell
Keyword(s):  
Mathematical Modeling ◽  
Time Series ◽  
Reproduction Number ◽  
Transmission Dynamics ◽  
The Novel ◽  
Epidemic Threshold ◽  
Transmission Potential ◽  
Incidence Data ◽  
The Mean ◽  
Novel Coronavirus

AbstractAn outbreak of COVID-19 developed aboard the Princess Cruises Ship during January-February 2020. Using mathematical modeling and time-series incidence data describing the trajectory of the outbreak among passengers and crew members, we characterize how the transmission potential varied over the course of the outbreak. Our estimate of the mean reproduction number in the confined setting reached values as high as ∼11, which is higher than mean estimates reported from community-level transmission dynamics in China and Singapore (approximate range: 1.1-7). Our findings suggest that Rt decreased substantially compared to values during the early phase after the Japanese government implemented an enhanced quarantine control. Most recent estimates of Rt reached values largely below the epidemic threshold, indicating that a secondary outbreak of the novel coronavirus was unlikely to occur aboard the Diamond Princess Ship.

Locational relationship between corpus luteum and ovulatory follicle on ovaries alters follicular dynamics and progesterone concentrations of Thai indigenous beef cows exhibiting two follicular waves

2019 ◽  
Vol 59 (12) ◽  
pp. 2161
Author(s):  
P. Yama ◽  
T. Moonmanee ◽  
M. Osathanunkul ◽  
J. Jitjumnong ◽  
W. Karaphuak
Keyword(s):  
Growth Rate ◽  
Corpus Luteum ◽  
Beef Cows ◽  
Follicular Waves ◽  
Ultrasound Monitoring ◽  
Ovulatory Follicle ◽  
The Mean ◽  
The Impact ◽  
The Relationship ◽  
Follicular Dynamics

The present study aims to determine the impact of differences in the locational relationship between the previous corpus luteum (CL) and the further ovulatory follicle (OF) on follicular dynamics and progesterone (P4) concentrations in Thai indigenous beef cows (White Lamphun) exhibiting two follicular waves. Twenty-one cows, exhibiting the two-wave follicular pattern, were studied through interovulatory intervals (IOI), and classified according to the relationship between the previous CL and the further OF on the cattle model ovaries. Classifications were outlined as either an ipsilateral (same ovary) relationship (n = 12), or a contralateral (opposite ovaries) relationship (n = 9). Ultrasound monitoring, which evaluated the follicular diameter, and collection of blood for determining the P4 concentration were performed each day throughout the IOI. The IOI was longer (P < 0.05) in the contralateral cows than in the ipsilateral cows (19.7 ± 0.33 days vs 18.5 ± 0.29 days). Cows with an ipsilateral relationship were found to have further OFs with greater (P < 0.05) diameters than were cows with a contralateral relationship (13.9 ± 0.31 mm vs 12.1 ± 0.21 mm). The mean growth rate of the further OF was greater (P = 0.05) in the ipsilateral cows than in the contralateral cows (1.1 ± 0.11 mm/day vs 0.8 ± 0.04 mm/day). On Day 17 of the IOI, the ipsilateral cows demonstrated their lowest concentration of P4 (P < 0.05). On Day 18 of the IOI, the concentrations of P4 tended to be lower (P = 0.09) in the ipsilateral cows than in the contralateral cows (0.6 ± 0.04 ng/mL vs 1.1 ± 0.12 ng/mL). The interval from the luteinisation until the end of the luteolysis was longer (P < 0.05) in the contralateral group than in the ipsilateral group (18.5 ± 0.50 days vs 16.7 ± 0.33 days). Thus, we conclude that in Thai indigenous beef cows, the growth rate and diameter of the further OF during luteolysis increases more in the ipsilateral relationship than in the contralateral relationship.

scholarly journals Management strategies for reducing variation in annual yield: when can they work?

2007 ◽  
Vol 64 (4) ◽  
pp. 698-701 ◽  
Author(s):  
Dankert W. Skagen
Keyword(s):  
Growth Rate ◽  
Management Strategies ◽  
Biological Properties ◽  
Low Risk ◽  
Simulation Studies ◽  
Fishing Mortality ◽  
Total Allowable Catch ◽  
Extreme Form ◽  
The Mean ◽  
The Relationship

Abstract Skagen, D. W. 2007. Management strategies for reducing variation in annual yield: when can they work? – ICES Journal of Marine Science, 64: 698–701. Management with permanently fixed quota, an extreme form of a catch-stabilizing strategy, poses the risk of severely depleting a stock. Simulation studies of artificial populations are conducted to show that the maximum fixed total allowable catch (TAC) consistent with a low risk of depletion is related to biological properties of the stock and to the fishing mortality (F) at the time the regime is introduced. If the stock can be assumed to be fully exploited, a safe fixed TAC can be derived as a percentage of the mean catch obtained previously under a constant-F regime. This percentage will be in the order of 50–100%, and is largely independent of the previous F-value. The lower end of the range is associated with large variations in recruitment and short lifespans, but is insensitive to the growth rate of a species. The relationship between previous catch and a safe fixed TAC can be used as a guideline in setting a precautionary TAC in data-poor situations.

A study of the relationship between plane of nutrition during lactation and certain production characteristics in autumn-calving suckler cows

1983 ◽  
Vol 37 (3) ◽  
pp. 353-363 ◽  
Author(s):  
S. H. Somerville ◽  
B. G. Lowman ◽  
R. A. Edwards ◽  
G. Jolly
Keyword(s):  
Growth Rate ◽  
Compensatory Growth ◽  
Live Weight ◽  
Beef Cows ◽  
Metabolizable Energy ◽  
Condition Score ◽  
The Mean ◽  
Daily Intakes ◽  
The Relationship ◽  
Production Characteristics

ABSTRACTHereford ♂ × British Friesian ♀ cows that had calved in September/October and were suckling mainly Charolais ♂ × calves were offered individually one of three planes of nutrition based on their estimated maintenance requirement during their first 150 days of lactation.The mean daily intakes of metabolizable energy were 95·8, 71·5 and 52·1 MJ for the high, medium and low planes of nutrition respectively. Data were collected from 122 lactations. The mean 150-day cumulative milk yields of the cows were 1 355, 1 258 and 1 187 kg for the high, medium and low planes of nutrition respectively (P < 0·001). A i-kg increase in calf birth weight was associated with an increase in 150-day cumulative milk yield of 14·7 ± 2·17 kg (P < 0·001). Losses in live weight and condition score were significantly greater for cows given the low plane of nutrition during lactation (P < 0001).Although there was a significant (P < 0·01) positive correlation between the growth rate of the calves and their dams' nutritional level during the winter there was evidence of compensatory growth at grass, since by the time of weaning in August, the plane of nutrition of the dam during the winter had no significant effect on the weight of the calves.The experiment demonstrates that energy-deficient beef cows will attempt to maintain milk production at the expense of body reserves and that when supplementary solid food is made available to the suckled calves, their weaning weights are unaffected by the plane of nutrition of the dam during the winter.

Ear branching as a means of increasing grain uniformity in wheat

1972 ◽  
Vol 23 (4) ◽  
pp. 551 ◽  
Author(s):  
HM Rawson ◽  
KN Ruwali
Keyword(s):  
Growth Rate ◽  
Light Intensity ◽  
Grain Growth ◽  
Growth Rates ◽  
Grain Filling ◽  
Size At Maturity ◽  
Grain Number ◽  
Photosynthetic System ◽  
Temperature Changes ◽  
The Relationship

Grain growth was compared in two field-grown wheats, Kalyan Sona, a high-yielding, seinidwarf line with few spikelets per ear and many grains per spikelet, and a branched-eared cultivar with many spikelets, each with few grains. The basis of comparison was the spikelet in Kalyan Sona and the branch in the branched material. Within the central spikelets of the main ear in Kalyan Sona, grain growth rates for the greater part of filling were b > a = c > d > e; final weights per grain for these florets were 42, 40, 37,26, and 12 mg respectively. The gradation in growth rate for the eight grains along the branch in the branched-eared cultivar was relatively small with the consequence that all grains were similar in size at maturity (range 39–43 mg); peak growth rates for all positions were at least as high as for grains a, b, and c in Kalyan Sona. In another cultivar, Triple Dirk, increasing competition for assimilates by reducing the light intensity during grain filling had a differential effect on grains within the spikelet but scarcely on the pattern between spikelets. The relationship between all grains was unaffected by temperature changes. The results are discussed in relation to competition for assimilates between grains, and the suggestion made that a high number of grains per spikelet may not use the available assimilates most efficiently. Ear branching is proposed as a preferable alternative, as this also provides abundant grain sites to utilize assimilates to the potential of the photosynthetic system, yet ensures grain uniformity per ear, regardless of grain number, by having few grains in each spikelet.

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