The Impact of Phosphorous Applications and Incubation Periods on P- Desorption Characteristics with Successive DMT-HFO-P Extractions on P Fixing Soils

Forecasting the spatiotemporal spread of infectious diseases during an outbreak is an important component of epidemic response. However, it remains challenging both methodologically and with respect to data requirements, as disease spread is influenced by numerous factors, including the pathogen’s underlying transmission parameters and epidemiological dynamics, social networks and population connectivity, and environmental conditions. Here, using data from Sierra Leone, we analyze the spatiotemporal dynamics of recent cholera and Ebola outbreaks and compare and contrast the spread of these two pathogens in the same population. We develop a simulation model of the spatial spread of an epidemic in order to examine the impact of a pathogen’s incubation period on the dynamics of spread and the predictability of outbreaks. We find that differences in the incubation period alone can determine the limits of predictability for diseases with different natural history, both empirically and in our simulations. Our results show that diseases with longer incubation periods, such as Ebola, where infected individuals can travel farther before becoming infectious, result in more long-distance sparking events and less predictable disease trajectories, as compared to the more predictable wave-like spread of diseases with shorter incubation periods, such as cholera.

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The employment of strontium to activate mouse oocytes: effects on spermatid-injection outcome

Reproduction ◽

10.1530/rep.1.00894 ◽

2006 ◽

Vol 131 (2) ◽

pp. 259-267 ◽

Cited By ~ 13

Author(s):

Jean Loren ◽

Orly Lacham-Kaplan

Keyword(s):

Birth Outcomes ◽

Round Spermatid ◽

Oocyte Activation ◽

Embryo Viability ◽

Blastocyst Development ◽

Incubation Periods ◽

Artificial Oocyte Activation ◽

The Impact ◽

Post Implantation ◽

Round Spermatid Injection

The present research investigated the effects of various strontium concentrations, in combination with different incubation periods, on mouse parthenogentic oocyte activation and blastocyst development. The results for blastocyst development showed a trend indicating that 10 mM strontium for 3 h was the optimal strontium protocol. Ethanol, an agent that incites oocyte activation via a monotonic rise in calcium, was employed as a control. The outcome of blastocyst formation arising from parthenogenic ethanol activation was significantly less (P < 0.001) than that achieved by the optimal strontium protocol. To assess the impact of strontium oocyte activation on embryo viability following fertilization with immature germ cells, the protocol of 10 mM strontium for 3 h was applied to oocytes injected with round spermatids and then compared with other protocols. The results indicate that following round-spermatid injection the benefits derived from strontium artificial oocyte activation are evident during both pre- and post-implantation development. However, in order to adjust the protocol to the most effective round-spermatid injection in relation to the oocyte cell cycle, injection was done 1.5 h after strontium activation followed by another 1.5 h activation in strontium. The implementation of round-spermatid injection in combination with this oocyte-activation protocol led to live-birth outcomes not significantly different to those outcomes obtained by mature spermatozoa.

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Soil phosphorus fractionation in calcareous soil as affected by organic amendments application

Polish Journal of Soil Science ◽

10.17951/pjss.2020.53.1.149 ◽

2020 ◽

Vol 53 (1) ◽

pp. 149

Author(s):

Adel Ghoneim, et al.

Keyword(s):

Calcareous Soil ◽

Management Practices ◽

Organic Amendments ◽

Chemical Extraction ◽

P Fractions ◽

Application Rates ◽

Sequential Chemical Extraction ◽

Incubation Periods ◽

The Impact ◽

Exchangeable P

<p>Understanding of P transformations following organic amendments addition to highly calcareous soils is necessary for developing better management practices that can help enhance P fertilizer use efficiency. Phosphorus solubility and availability for plant uptake under the conditions of arid calcareous soil is very low, making P nutrient supply a critical issue under these conditions. The aim of this study was to evaluate the impact of various types of organic amendments (chicken compost, cow compost and a mixture of humic-fulvic acid) applied alone at different rates of KH2PO4 fertilizer on P fractions in calcareous soil using the sequential chemical extraction method. Amended calcareous soil was incubated under laboratory conditions and soil samples were collected at 0, 4, 8 and 16 weeks of the incubation periods. Soil was sequentially extracted and analyzed for P different fractions. The results indicated that the addition of chicken and cow compost increased soluble and exchangeable-P and Ca-P fractions in calcareous soil and the increases depend on application rates. The results indicated that combination of chicken and cow compost with different KH2PO4 fertilizer application rates increased the concentration of soluble and exchangeable-P in the soil compared to organic amendments or KH2PO4 fertilizer applied alone. The P associated with Ca was the dominant P fractions in soil, ranging between 51 to 59% regardless of the different treatment and the period of incubations. The Al- and Fe-associated P fractions varied between 2 and 9%, with the maximum value being observed at the eighth week of incubation. The residual-P fraction ranged between 5 and 22% at different incubation periods.</p>

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The Impact of fodder on Bombyx Mori

10.1101/245654 ◽

2018 ◽

Author(s):

Victor Flores ◽

Katherine Medina

Keyword(s):

Bombyx Mori ◽

Production Performance ◽

P Value ◽

Demographic Profiles ◽

Silk Production ◽

Incubation Periods ◽

The Mean ◽

The Impact ◽

Cluster 2 ◽

Production Characteristics

AbstractSilk production by the Chilean silkworm, although an important source of revenue, has not been extensively studied. In the current study, we research 564 Mountain Silkworm (Bombyx mori), analyzing their silk harvests, silk production incubation periods and demographic profiles. The mountain silkworms were randomly divided into two clusters (cluster#1, cluster#2), each of which had 56 mountain silkworms. Crumpled maize were replaced by steam-flaked maize 30%, 50%, 100%, then researched the effects of nourishing steam-flaked maize on production performance of silk production by silkworm. The outcomes showed that the cluster#2 had better median silk harvest than cluster#1, the mean of these increment silk harvests was 3.48pounds (P-value <0.05); the protein proportion and the sugar in silk of cluster#2 went up than cluster#1; for the urine nitrogen and somatic cell count of cluster#2 were lower than cluster#1 by 0.9% (P-value >0.05), 30,800 cells/ml (P-value<0.05), respectively. The current research confirmed that utilizing the JHO nutrition heightened silk harvest, improved silk production characteristics, and enhanced the performance of mountain silkworms; furthermore, it heightened resistance to the sickness due to strengthened resistance.

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Incubation periods impact the spatial predictability of outbreaks: analysis of cholera and Ebola outbreaks in Sierra Leone

10.1101/19003525 ◽

2019 ◽

Author(s):

Rebecca Kahn ◽

Corey M. Peak ◽

Juan Fernández-Gracia ◽

Alexandra Hill ◽

Amara Jambai ◽

...

Keyword(s):

Infectious Diseases ◽

Sierra Leone ◽

Incubation Period ◽

Population Connectivity ◽

Disease Spread ◽

Long Distance ◽

Spatial Spread ◽

Transmission Parameters ◽

Incubation Periods ◽

The Impact

AbstractForecasting the spatiotemporal spread of infectious diseases during an outbreak is an important component of epidemic response. However, it remains challenging both methodologically and with respect to data requirements as disease spread is influenced by numerous factors, including the pathogen’s underlying transmission parameters and epidemiological dynamics, social networks and population connectivity, and environmental conditions. Here, using data from Sierra Leone we analyze the spatiotemporal dynamics of recent cholera and Ebola outbreaks and compare and contrast the spread of these two pathogens in the same population. We develop a simulation model of the spatial spread of an epidemic in order to examine the impact of a pathogen’s incubation period on the dynamics of spread and the predictability of outbreaks. We find that differences in the incubation period alone can determine the limits of predictability for diseases with different natural history, both empirically and in our simulations. Our results show that diseases with longer incubation periods, such as Ebola, where infected individuals can travel further before becoming infectious, result in more long-distance sparking events and less predictable disease trajectories, as compared to the more predictable wave-like spread of diseases with shorter incubation periods, such as cholera.Significance statementUnderstanding how infectious diseases spread is critical for preventing and containing outbreaks. While advances have been made in forecasting epidemics, much is still unknown. Here we show that the incubation period – the time between exposure to a pathogen and onset of symptoms – is an important factor in predicting spatiotemporal spread of disease and provides one explanation for the different trajectories of the recent Ebola and cholera outbreaks in Sierra Leone. We find that outbreaks of pathogens with longer incubation periods, such as Ebola, tend to have less predictable spread, whereas pathogens with shorter incubation periods, such as cholera, spread in a more predictable, wavelike pattern. These findings have implications for the scale and timing of reactive interventions, such as vaccination campaigns.

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2367. Selecting Testing Frequency for Estimation of Incubation Periods: A Simulation Study Based on Clostridioides difficile Observations

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.2045 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S816-S816

Author(s):

Brigid Wilson ◽

Mustafa S Ascha ◽

Justin O’Hagan ◽

Curtis Donskey

Keyword(s):

Incubation Period ◽

Simulation Study ◽

Symptom Onset ◽

Pathogen Transmission ◽

Sample Sizes ◽

Clostridioides Difficile ◽

Testing Frequency ◽

Incubation Periods ◽

Interval Censored ◽

The Impact

Abstract Background Estimates of the incubation period (time between pathogen transmission and symptom onset) for an infection inform infection control and prevention measures. However, observation of the exact transmission and onset times rarely occurs and “coarse,” or doubly interval-censored, data about these exact times are typically used for estimation. The effect of coarseness on the required number of symptomatic cases and the uncertainty of the estimates is unknown, prompting a simulation study informed by data from an investigation of the incubation period of Clostridioides difficile. Methods We simulated incubation period data assuming a log-normal distribution, a true median incubation period of 7 days, and a standard deviation of 1 day for sample sizes of 50 to 300 symptomatic cases. For each sample size, we simulated 1000 datasets and examined the impact of testing frequencies, considering intervals between tests of 0.25 to 2 times the median incubation period (1.75 to 14 days) about both transmission and symptom onset times. With these doubly interval-censored observed values, we fit accelerated failure time models to estimate the median incubation time and its 95% confidence interval (CI). Comparing the coverage of the true median and the widths of the CIs, we summarized simulation results across sample sizes and testing frequencies. Results Model results from all combinations of sample sizes and testing frequencies yielded median incubation period CIs close to the target 95% coverage level (Figure 1). The width of the 95% CI about the median decreased with larger sample sizes and shorter times between tests (Figure 2). Thus, similar estimates and confidence intervals would be observed from 100 symptomatic cases with a testing frequency of 3.5 days as from 200 symptomatic cases tested every 14 days. Conclusion The frequency of testing is a key factor in planning studies to estimate incubation periods for infectious diseases. To achieve a desired degree of certainty in estimation, increased frequency of testing can reduce the number of symptomatic cases required. We showed that simulations can assist in planning natural history studies, and these methods could be extended to include population data (e.g., transmission incidence) and cost constraints. Disclosures All authors: No reported disclosures.

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Formation of Lunar Craters and Bright Rays as a Result of Meteorite Impacts

Symposium - International Astronomical Union ◽

10.1017/s0074180900178404 ◽

1962 ◽

Vol 14 ◽

pp. 415-418

Author(s):

K. P. Stanyukovich ◽

V. A. Bronshten

Keyword(s):

Explosive Charge ◽

The Moon ◽

Meteorite Impacts ◽

The Earth ◽

Lunar Craters ◽

The Impact

The phenomena accompanying the impact of large meteorites on the surface of the Moon or of the Earth can be examined on the basis of the theory of explosive phenomena if we assume that, instead of an exploding meteorite moving inside the rock, we have an explosive charge (equivalent in energy), situated at a certain distance under the surface.

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The Geosciences Applied to Lunar Exploration

Symposium - International Astronomical Union ◽

10.1017/s0074180900178222 ◽

1962 ◽

Vol 14 ◽

pp. 169-257 ◽

Cited By ~ 9

Author(s):

J. Green

Keyword(s):

Lunar Surface ◽

Probable Mechanism ◽

Point Of View ◽

Lunar Exploration ◽

Geological Model ◽

Apply Geophysics ◽

Surface Features ◽

The Impact

The term geo-sciences has been used here to include the disciplines geology, geophysics and geochemistry. However, in order to apply geophysics and geochemistry effectively one must begin with a geological model. Therefore, the science of geology should be used as the basis for lunar exploration. From an astronomical point of view, a lunar terrain heavily impacted with meteors appears the more reasonable; although from a geological standpoint, volcanism seems the more probable mechanism. A surface liberally marked with volcanic features has been advocated by such geologists as Bülow, Dana, Suess, von Wolff, Shaler, Spurr, and Kuno. In this paper, both the impact and volcanic hypotheses are considered in the application of the geo-sciences to manned lunar exploration. However, more emphasis is placed on the volcanic, or more correctly the defluidization, hypothesis to account for lunar surface features.

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Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

International Astronomical Union Colloquium ◽

10.1017/s0252921100014718 ◽

1997 ◽

Vol 161 ◽

pp. 197-201 ◽

Cited By ~ 1

Author(s):

Duncan Steel

Keyword(s):

Probability Distributions ◽

Regions Of Interest ◽

Significant Fraction ◽

Organic Chemicals ◽

Impact Speed ◽

The Mean ◽

The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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Organic Syntheses During the Impact of a Comet with a Gaseous Planet

International Astronomical Union Colloquium ◽

10.1017/s0252921100014706 ◽

1997 ◽

Vol 161 ◽

pp. 189-195

Author(s):

Cesare Guaita ◽

Roberto Crippa ◽

Federico Manzini

Keyword(s):

Polymeric Material ◽

Molecular Form ◽

Parent Compound ◽

Blue Filter ◽

Organic Syntheses ◽

The Impact

AbstractA large amount of CO has been detected above many SL9/Jupiter impacts. This gas was never detected before the collision. So, in our opinion, CO was released from a parent compound during the collision. We identify this compound as POM (polyoxymethylene), a formaldehyde (HCHO) polymer that, when suddenly heated, reformes monomeric HCHO. At temperatures higher than 1200°K HCHO cannot exist in molecular form and the most probable result of its decomposition is the formation of CO. At lower temperatures, HCHO can react with NH3 and/or HCN to form high UV-absorbing polymeric material. In our opinion, this kind of material has also to be taken in to account to explain the complex evolution of some SL9 impacts that we observed in CCD images taken with a blue filter.

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