scholarly journals Time scale of ovarian maturation in Greenland halibut (Reinhardtius hippoglossoides, Walbaum)

2003 ◽  
Vol 60 (4) ◽  
pp. 767-773 ◽  
Author(s):  
S Junquera ◽  
E Román ◽  
J Morgan ◽  
M Sainza ◽  
G Ramilo
Keyword(s):  
Ovarian Development ◽  
Data Series ◽  
Development Phase ◽  
Greenland Halibut ◽  
Annual Basis ◽  
Time Period ◽  
Greenland Halibut Reinhardtius Hippoglossoides ◽  
Long Time ◽  
The Mean ◽  
One Year

Abstract Evidence for a prolonged ovarian development phase in Greenland halibut is presented. The reproductive cycle in this species was originally described based on the assumption that this phase should last about one year. The results of the present study, which involves data series covering a long time period and different geographic areas, show instead that there is more than one year between the mean age of the females that are at the onset of ovarian development and the mean age of the females that are actually spawning. There are two possible interpretations for this observation. One is that the ovarian development phase (vitellogenesis) could last more than one year and thus as a consequence, individual spawning would not necessarily occur on an annual basis. The other would be the existence of a high proportion of non-spawning females every year for other reasons not related with the natural rhythm of oocyte development.

scholarly journals Long time frames to detect the impact of changing COVID-19 measures, Canada, March to July 2020

2021 ◽  
Vol 26 (40) ◽  
Author(s):  
Jessica E Stockdale ◽  
Renny Doig ◽  
Joosung Min ◽  
Nicola Mulberry ◽  
Liangliang Wang ◽  
...  
Keyword(s):  
Population Level ◽  
Time Frame ◽  
Control Measures ◽  
Type Model ◽  
Time Period ◽  
Long Time ◽  
The Mean ◽  
Reported Data ◽  
Time Frames ◽  
The Impact

Background Many countries have implemented population-wide interventions to control COVID-19, with varying extent and success. Many jurisdictions have moved to relax measures, while others have intensified efforts to reduce transmission. Aim We aimed to determine the time frame between a population-level change in COVID-19 measures and its impact on the number of cases. Methods We examined how long it takes for there to be a substantial difference between the number of cases that occur following a change in COVID-19 physical distancing measures and those that would have occurred at baseline. We then examined how long it takes to observe this difference, given delays and noise in reported cases. We used a susceptible-exposed-infectious-removed (SEIR)-type model and publicly available data from British Columbia, Canada, collected between March and July 2020. Results It takes 10 days or more before we expect a substantial difference in the number of cases following a change in COVID-19 control measures, but 20–26 days to detect the impact of the change in reported data. The time frames are longer for smaller changes in control measures and are impacted by testing and reporting processes, with delays reaching ≥ 30 days. Conclusion The time until a change in control measures has an observed impact is longer than the mean incubation period of COVID-19 and the commonly used 14-day time period. Policymakers and practitioners should consider this when assessing the impact of policy changes. Rapid, consistent and real-time COVID-19 surveillance is important to minimise these time frames.

Reliability Analysis for the Power and Propulsion System of Stratospheric Airship

2012 ◽  
Vol 225 ◽  
pp. 511-516
Author(s):  
Jian Liu ◽  
Quan Bao Wang ◽  
Jian Chen ◽  
Deng Ping Duan ◽  
Shu Wang
Keyword(s):  
Power System ◽  
High Reliability ◽  
Propulsion System ◽  
Cell Array ◽  
Reliability Design ◽  
Reliability Models ◽  
Stratospheric Airship ◽  
Time Period ◽  
Long Time ◽  
One Year

For meeting requirements of staying in the stratosphere for a long time period more than one year and less of maintenance, the power and propulsion system of the stratospheric airship is required to have high reliability. In this regard, reliability design is a key procedure in the design phase of the power and propulsion system of stratospheric airship. This paper focuses on the quantitative analysis of the reliability for the power and propulsion system of the stratospheric airship. Firstly, the reliability of the solar cell array and the fuel cell of power system are discussed respectively. Then, different topologies of the power system are discussed and compared. The reliability of the propulsion system is also analyzed in different configurations. The reliability of the basic combination of the power and propulsion system is discussed. For improving reliability, a new type of combination for the power and propulsion system is proposed. Reliability models of proposed combination are created through simplification. The ZhiYuan-1 is used as a demonstration problem to show the capability of this reliability-improved method. The result shows that the reliability of ZhiYuan-1 power and propulsion system increases by 12.8%.

scholarly journals Long time frames to detect the impact of changing COVID-19 control measures

2020 ◽  
Author(s):  
Jessica E Stockdale ◽  
Renny Doig ◽  
Joosung Min ◽  
Nicola Mulberry ◽  
Liangliang Wang ◽  
...  
Keyword(s):  
Population Level ◽  
Time Frame ◽  
Control Measures ◽  
Policy Makers ◽  
Time Period ◽  
Reporting Process ◽  
Long Time ◽  
The Mean ◽  
Time Frames ◽  
The Impact

AbstractBackgroundMany countries have implemented population-wide interventions such as physical distancing measures, in efforts to control COVID-19. The extent and success of such measures has varied. Many jurisdictions with declines in reported COVID-19 cases are moving to relax measures, while others are continuing to intensify efforts to reduce transmission.AimWe aim to determine the time frame between a change in COVID-19 measures at the population level and the observable impact of such a change on cases.MethodsWe examine how long it takes for there to be a substantial difference between the cases that occur following a change in control measures and those that would have occurred at baseline. We then examine how long it takes to detect a difference, given delays and noise in reported cases. We use changes in population-level (e.g., distancing) control measures informed by data and estimates from British Columbia, Canada.ResultsWe find that the time frames are long: it takes three weeks or more before we might expect a substantial difference in cases given a change in population-level COVID-19 control, and it takes slightly longer to detect the impacts of the change. The time frames are shorter (11-15 days) for dramatic changes in control, and they are impacted by noise and delays in the testing and reporting process, with delays reaching up to 25-40 days.ConclusionThe time until a change in broad control measures has an observed impact is longer than is typically understood, and is longer than the mean incubation period (time between exposure than onset) and the often used 14 day time period. Policy makers and public health planners should consider this when assessing the impact of policy change, and efforts should be made to develop rapid, consistent real-time COVID-19 surveillance.

New station-specific limits in phenology to improve data quality during online-data-entry

2020 ◽  
Author(s):  
Barbara Pietragalla ◽  
Linda Füzér
Keyword(s):  
Standard Deviation ◽  
Data Quality ◽  
Data Entry ◽  
Data Series ◽  
Online Data ◽  
Expected Time ◽  
Time Period ◽  
Specific Standard ◽  
The Mean ◽  
Phenological Event

<p>The Swiss phenology network operated by MeteoSwiss counts approximately 160 stations where up to 69 phenological events are observed by private persons. Currently, 68% of the observer transmit their data online by a recently developed tool called Phenotool. In order to reduce typing errors during the entry of the data, the values are instantly checked by Phenotool. The observer receives a visual warning if the data exceeds defined limits of an expected time-period giving him the opportunity to verify the date entered. The defined limits need to be as suitable as possible for each station and phenological event as numerous false warnings reduce the sensitivity of the observers and cause them to ignore the warning. <br>Until June 2019, limits had been used for five altitudinal layers and for each phenological event resulting from the mean ± 2 SD (standard deviation) rounded to the nearest 10. However, for some stations these limits were not appropriate, therefore, we decided to calculate station specific limits as follows: The median and SD was calculated for each phenological series consisting of at least 10 observations. In a second step, the mean of all SDs < 20 days was calculated and 2.5 times SD added/subtracted from the median. This approach leads to the same range of the limits for each phenological event, while the start of the limits is specific for each stations depending on the previously calculated median. If we would have used a station-specific standard deviation, stations with high variability and often less accurate data, would have been “awarded” with a large range. <br>For new stations, data-series consisting of less than 10 observations or deviant data-series, we calculated the limits with the mean standard deviations as described above and a predicted median from a linear regression model showing the relationship between the medians of a specific phenological event and the station heights. Deviant data-series were recognized by a difference larger than 30 days between modelled and calculated median.<br>The comparison of the old and new limits revealed that the newly calculated limits have an average range which is 8.52 days smaller. 55 out of the 69 phenological events have a smaller range, two has the same, and the remaining 12 have a larger range. Using the previous limits, in average 8.12% of the data from 1985-2019 was outside the defined ranges, however, applying the new limits results in 3.98% of the observations not fitting the limits. Considering the fact that the new limits have in average a smaller range, this improvement becomes even more significant. To conclude, we can say that the new limits produce clearly less warnings and more appropriate warnings in Phenotool enhancing data quality.</p>

ASPECTOS DA BIOLOGIA REPRODUTIVA DE SEIS ESPÉCIES DE PEIXES DE IMPORTÂNCIA COMERCIAL DO MÉDIO RIO XINGU – BASES PARA SEU MANEJO

2008 ◽  
Vol 3 (1) ◽  
pp. 64-77 ◽  
Author(s):  
Mauricio Camargo ◽  
Walmir Mário Alves Lima Júnior
Keyword(s):  
Spawning Season ◽  
Development Phase ◽  
Spawning Behavior ◽  
Spawning Activity ◽  
Macroscopic Scale ◽  
Flood Season ◽  
First Reproduction ◽  
Flood Pulses ◽  
The Mean ◽  
One Year

The spawning season and the mean length at first reproduction (L50) of Cichla melaniae, Prochilodus nigricans, Plagioscion squamossisimus, P. magdalenae, Myleus torquatus and M. pacu were studied. Seven field collections were made along one year. The captures were carried out with the use of gill nets. The weight and the total length of all the specimens caught were assessed. The sex and the development phase of gonads were established based in a macroscopic scale of four stages. The main season of reproduction was defined and compared with the seasonality of the flood pulses. The tucunaré (Cichla melaniae) and the curimatã (Prochilodus nigricans) showed synchronic spawns at the beginning of the flood season. Other species, such as the pacus (M. torquatus and M. pacu), although presenting a synchronic spawning strategy, also showed another pick of spawning activity during the dry season. The pescada P. squamossisimus, presented assinchronic spawning behavior along the whole year. The mean lengths at the beginning of the sexual maturation were: 26,45 cm for Cichla melaniae; 24,96 cm for P. squamossisimus; 22,25 cm for P. magdalenae; 23,08 cm for P. nigricans; 16,18 cm for M. torquatus; and 16,89 cm for M. pacu. Comparing these results with the landing volume, indicate that M. torquatus and M. pacu are captured in lengths far bellow (12-14 cm) the calculated L50. The closed seasons of this fishery not always coincide with the spawning season of pacus (Myleus). We suggest the establishment of minimum sizes of capture, based in the L50 calculated for each one of the studied species.

scholarly journals Third-Body Perturbation in the Case of Elliptic Orbits for the Disturbing Body

2008 ◽  
Vol 2008 ◽  
pp. 1-14 ◽  
Author(s):  
R. C. Domingos ◽  
R. Vilhena de Moraes ◽  
A. F. Bertachini De Almeida Prado
Keyword(s):  
Numerical Study ◽  
Orbital Elements ◽  
Third Body ◽  
Smooth Curves ◽  
The Earth ◽  
Elliptic Orbits ◽  
Time Period ◽  
Long Time ◽  
The Mean ◽  
The Stability

This work presents a semi-analytical and numerical study of the perturbation caused in a spacecraft by a third-body using a double averaged analytical model with the disturbing function expanded in Legendre polynomials up to the second order. The important reason for this procedure is to eliminate terms due to the short periodic motion of the spacecraft and to show smooth curves for the evolution of the mean orbital elements for a long-time period. The aim of this study is to calculate the effect of lunar perturbations on the orbits of spacecrafts that are traveling around the Earth. An analysis of the stability of near-circular orbits is made, and a study to know under which conditions this orbit remains near circular completes this analysis. A study of the equatorial orbits is also performed.

scholarly journals Incomplete Kawasaki disease - a diagnostic and therapeutic challenge

2014 ◽  
Vol 9 (4) ◽  
pp. 30-35
Author(s):  
S Datta ◽  
S Maiti ◽  
G Das ◽  
A Chatterjee ◽  
P Ghosh
Keyword(s):  
Kawasaki Disease ◽  
Intravenous Immunoglobulin ◽  
Incomplete Kawasaki Disease ◽  
Duration Of Symptoms ◽  
Clinical Criteria ◽  
Echocardiographic Finding ◽  
2D Echocardiography ◽  
Acquired Heart Disease ◽  
The Mean ◽  
One Year

Background The diagnosis of classical Kawasaki Disease was based on clinical criteria. The conventional criteria is particularly useful in preventing over diagnosis, but at the same time it may result in failure to recognize the incomplete form of Kawasaki Disease. Objective To suspect incomplete Kawasaki Disease, because early diagnosis and proper treatment may reduce substantial risk of developing coronary artery abnormality which is one of the leading causes of acquired heart disease in children. Method Nine cases of incomplete Kawasaki Disease were diagnosed over a period of one year. The diagnosis of incomplete Kawasaki Disease was based on fever for five days with less than four classical clinical features and cardiac abnormality detected by 2D- echocardiography. A repeat echocardiography was done after 6 weeks of onset of illness. The patients were treated with Intravenous Immunoglobulin and/or aspirin. Result The mean age of the patients was 3.83 years and the mean duration of symptoms before diagnosis was 12.1 days. Apart from other criteria all of our patients had edema and extreme irritability. All the patients had abnormal echocardiographic finding. Five patients received only aspirin due to nonaffordability of Intravenous Immunoglobulin and four patients received both aspirin and Intravenous Immunoglobulin, but the outcome was excellent in all the cases. Conclusion Incomplete Kawasaki Disease can be diagnosed with more awareness and aspirin alone may be used as a second line therapy in case of non affordability of Intravenous Immunoglobulin. Journal of College of Medical Sciences-Nepal, 2013, Vol-9, No-4, 30-35 DOI: http://dx.doi.org/10.3126/jcmsn.v9i4.10234

scholarly journals Internet page content analysis of north European Sea ports

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Olli-Pekka Hilmola ◽  
Andres Tolli ◽  
Ain Kiisler
Keyword(s):  
Content Analysis ◽  
Environmental Issues ◽  
Basic Design ◽  
Time Period ◽  
Long Time ◽  
Sea Ports ◽  
Selection Of

Abstract This study analyses 98 Internet pages of sea ports located in Sweden, Finland and Estonia during years 2017–2019. Aim of the study is to find, how website basic design is completed (colours and languages), how slogans, environmental issues, statistics and hinterland transports are reported. Based on the analysis, it appears as rather common that sea ports follow conservative selection of colours in their websites, where blue and white are clearly most popular. Typically, English and Swedish are as the most common used language, followed by Finnish, Russian and Estonian. In some rare cases, websites are offered in Chinese or German. Larger sea ports do have clear “slogans”, where smaller ones are just having lengthy justification for their existence. Environmental issues are increasing concern among sea ports, and these are mostly mentioned in details within Swedish actors. Providing statistics varies among companies, and in some sea ports these are provided from very long time period, where in others from just previous years or then only from last year (or even at all). It is common for companies to report that they have sustainable hinterland access, railway available.

scholarly journals Personal Exposure Assessment to Wi-Fi Radiofrequency Electromagnetic Fields in Mexican Microenvironments

2021 ◽  
Vol 18 (4) ◽  
pp. 1857
Author(s):  
Raquel Ramirez-Vazquez ◽  
Jesus Gonzalez-Rubio ◽  
Isabel Escobar ◽  
Carmen del Pilar Suarez Rodriguez ◽  
Enrique Arribas
Keyword(s):  
Risk Perception ◽  
Electromagnetic Fields ◽  
Personal Exposure ◽  
Wireless Internet ◽  
European Cities ◽  
Radiofrequency Electromagnetic Fields ◽  
Time Period ◽  
The Mean ◽  
Personal Exposure Assessment ◽  
Study Participants

In recent years, personal exposure to Radiofrequency Electromagnetic Fields (RF-EMF) has substantially increased, and most studies about RF-EMF with volunteers have been developed in Europe. To the best of our knowledge, this is the first study carried out in Mexico with personal exposimeters. The main objective was to measure personal exposure to RF-EMF from Wireless Fidelity or wireless Internet connection (Wi-Fi) frequency bands in Tamazunchale, San Luis Potosi, Mexico, to compare results with maximum levels permitted by international recommendations and to find if there are differences in the microenvironments subject to measurements. The study was conducted with 63 volunteers in different microenvironments: home, workplace, outside, schools, travel, and shopping. The mean minimum values registered were 146.5 μW/m2 in travel from the Wi-Fi 2G band and 116.8 μW/m2 at home from the Wi-Fi 5G band, and the maximum values registered were 499.7 μW/m2 and 264.9 μW/m2 at the workplace for the Wi-Fi 2G band and the Wi-Fi 5G band, respectively. In addition, by time period and type of day, minimum values were registered at nighttime, these values being 129.4 μW/m2 and 93.9 μW/m2, and maximum values were registered in the daytime, these values being 303.1 μW/m2 and 168.3 μW/m2 for the Wi-Fi 2G and Wi-Fi 5G bands, respectively. In no case, values exceeded limits established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Of the study participants (n = 63), a subgroup (n = 35) answered a survey on risk perception. According to these results, the Tamazunchale (Mexico) population is worried about this situation in comparison with several European cities; however, the risk perception changes when they are informed about the results for the study.

scholarly journals One Year of the COVID-19 Pandemic in Galicia: A Global View of Age-Group Statistics during Three Waves

2021 ◽  
Vol 18 (10) ◽  
pp. 5104
Author(s):  
Iván Area ◽  
Henrique Lorenzo ◽  
Pedro J. Marcos ◽  
Juan J. Nieto
Keyword(s):  
Intensive Care Unit ◽  
Hospital Admissions ◽  
Age Groups ◽  
Age Group ◽  
Nw Spain ◽  
The Past ◽  
Global View ◽  
Time Period ◽  
Key Variables ◽  
One Year

In this work we look at the past in order to analyze four key variables after one year of the COVID-19 pandemic in Galicia (NW Spain): new infected, hospital admissions, intensive care unit admissions and deceased. The analysis is presented by age group, comparing at each stage the percentage of the corresponding group with its representation in the society. The time period analyzed covers 1 March 2020 to 1 April 2021, and includes the influence of the B.1.1.7 lineage of COVID-19 which in April 2021 was behind 90% of new cases in Galicia. It is numerically shown how the pandemic affects the age groups 80+, 70+ and 60+, and therefore we give information about how the vaccination process could be scheduled and hints at why the pandemic had different effects in different territories.

Sign in / Sign up

Export Citation Format

Share Document