scholarly journals Comparing arenavirus infection patterns in experimentally and naturally infected rodent hosts

2017 ◽  
Author(s):  
Joachim Mariën ◽  
Benny Borremans ◽  
Sophie Gryseels ◽  
Bram Vanden Broecke ◽  
Beate Becker-Ziaja ◽  
...  

AbstractInfectious diseases of wildlife are typically studied using data on antibody and pathogen presence/level. In order to interpret these data, it is necessary to know the course of antibodies and pathogen presence/levels after infection. Such data are typically collected using experimental infection studies in which host individuals are inoculated in the laboratory and sampled over an extended period, but because laboratory conditions are controlled and much less variable than natural conditions, the immune response and pathogen dynamics may differ. Here, we compared Morogoro arenavirus infection patterns between naturally and experimentally infected multimammate mice (Mastomys natalensis). Longitudinal samples were collected during three months of bi-weekly trapping in Morogoro, Tanzania, and antibody titer and viral RNA presence were determined to assess whether the natural temporal patterns are similar to those previously observed in the laboratory. A good match with laboratory data was found for 52% of naturally infected individuals, while most of the mismatches can be explained by the presence of chronically infected individuals (35%), maternal antibodies (10%) and an antibody detection limit (25%). These results suggest that while laboratory data are useful for interpreting field samples, there can still be differences due to conditions that were not tested in the laboratory.Important noticeThis is a pre-print version of the manuscript, made available through bioRxiv.org. Note that this manuscript has not yet been peer-reviewed, and has been submitted to a peer-reviewed journal.

1984 ◽  
Vol 23 (01) ◽  
pp. 15-22
Author(s):  
Y. Sekita ◽  
T. Ohta ◽  
M. Inoue ◽  
H. Takeda

SummaryJudgements of examinees’ health status by doctors and by the examinees themselves are compared applying multiple discriminant analysis. The doctors’ judgements of the examinees’ health status are studied comparatively using laboratory data and the examinees’ subjective symptom data.This data was obtained in an Automated Multiphasic Health Testing System. We discuss the health conditions which are significant for the judgement of doctors about the examinees. The results show that the explanatory power, when using subjective symptom data, is fair in the case of the doctors’ judgement. We found common variables, such as nervousness, lack of perseverance etc., which form the first canonical axis.


Land ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 458
Author(s):  
Tara A. Ippolito ◽  
Jeffrey E. Herrick ◽  
Ekwe L. Dossa ◽  
Maman Garba ◽  
Mamadou Ouattara ◽  
...  

Smallholder agriculture is a major source of income and food for developing nations. With more frequent drought and increasing scarcity of arable land, more accurate land-use planning tools are needed to allocate land resources to support regional agricultural activity. To address this need, we created Land Capability Classification (LCC) system maps using data from two digital soil maps, which were compared with measurements from 1305 field sites in the Dosso region of Niger. Based on these, we developed 250 m gridded maps of LCC values across the region. Across the region, land is severely limited for agricultural use because of low available water-holding capacity (AWC) that limits dry season agricultural potential, especially without irrigation, and requires more frequent irrigation where supplemental water is available. If the AWC limitation is removed in the LCC algorithm (i.e., simulating the use of sufficient irrigation or a much higher and more evenly distributed rainfall), the dominant limitations become less severe and more spatially varied. Finally, we used additional soil fertility data from the field samples to illustrate the value of collecting contemporary data for dynamic soil properties that are critical for crop production, including soil organic carbon, phosphorus and nitrogen.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Atiporn Boonyai ◽  
Anchalee Thongput ◽  
Thidarat Sisaeng ◽  
Parisut Phumchan ◽  
Navin Horthongkham ◽  
...  

Abstract Background Prevalence and incidence of hepatitis caused by HEV infection are usually higher in developing countries. This study demonstrated the HEV seroprevalence and incidence of HEV infection in patients with clinical hepatitis in a tertiary hospital in Thailand. Methods A laboratory-based cross-sectional study was conducted using 1106 serum samples from patients suspected of HEV infection sent to the Serology laboratory, Siriraj Hospital, for detecting HEV antibodies during 2015–2018. Prevalence of anti-HEV IgG and IgM antibodies in general patients, including organ transplant recipients and pregnant women in a hospital setting, were determined using indirect enzyme-linked immunosorbent assay (ELISA) kits. Comparison of laboratory data between groups with different HEV serological statuses was performed. Results HEV IgG antibodies were detected in 40.82% of 904 serum samples, while HEV IgM antibodies were detected in 11.75% of 1081 serum samples. Similar IgG and IgM antibody detection rates were found in pregnant women. Interestingly, anti-HEV IgM antibodies were detected in 38.5% of patients who underwent organ transplantation. Patients who tested positive for anti-HEV IgM antibodies had higher alanine aminotransferase levels than those who had not. In contrast, patients who tested positive for anti-HEV IgG had more elevated levels of total bilirubin than those who tested negative. Conclusions HEV seroprevalence and incidence in patients with clinical hepatitis were relatively high in the Thai population, including the pregnancy and organ transplant subgroups. The results potentially benefit the clinicians in decision-making to investigate HEV antibodies and facilitating proper management for patients.


2015 ◽  
Vol 12 (103) ◽  
pp. 20141184 ◽  
Author(s):  
Konstans Wells ◽  
Barry W. Brook ◽  
Robert C. Lacy ◽  
Greg J. Mutze ◽  
David E. Peacock ◽  
...  

Infectious diseases can exert a strong influence on the dynamics of host populations, but it remains unclear why such disease-mediated control only occurs under particular environmental conditions. We used 16 years of detailed field data on invasive European rabbits ( Oryctolagus cuniculus ) in Australia, linked to individual-based stochastic models and Bayesian approximations, to test whether (i) mortality associated with rabbit haemorrhagic disease (RHD) is driven primarily by seasonal matches/mismatches between demographic rates and epidemiological dynamics and (ii) delayed infection (arising from insusceptibility and maternal antibodies in juveniles) are important factors in determining disease severity and local population persistence of rabbits. We found that both the timing of reproduction and exposure to viruses drove recurrent seasonal epidemics of RHD. Protection conferred by insusceptibility and maternal antibodies controlled seasonal disease outbreaks by delaying infection; this could have also allowed escape from disease. The persistence of local populations was a stochastic outcome of recovery rates from both RHD and myxomatosis. If susceptibility to RHD is delayed, myxomatosis will have a pronounced effect on population extirpation when the two viruses coexist. This has important implications for wildlife management, because it is likely that such seasonal interplay and disease dynamics has a strong effect on long-term population viability for many species.


2020 ◽  
Vol 23 (4) ◽  
pp. 451-471
Author(s):  
Michael D. White

Over the last few years, there has been a series of high-profile, premeditated ambush attacks on police, which has led some to conclude there is a “war on cops.” Unfortunately, prior research has not examined the prevalence of police ambushes over an extended period of time, and the most recent study only analyzed the phenomenon through 2013. Moreover, the “war on cops” thesis implies a very specific motivation for an ambush: hatred of police or desire to seek vengeance in response to police killings of citizens. Prior research has not sufficiently explored the motivations of ambush attacks, or whether recent trends in ambushes are linked to a “war on cops” motive. I investigate ambush killings of police from 1970 to 2018 using data from the Officer Down Memorial Page in an attempt to address these research gaps. I apply a temporal coding scheme of when the attack occurred to isolate killings of police that are consistent with the International Association of Chiefs of Police definition of an ambush. Results from linear regression show that the annual rates of ambush killings of police have declined by more than 90% since 1970. Although ambushes spiked in 2016 and 2018 to the highest rates in 20 years, interrupted time series analysis indicates no statistically significant increase post-2013. Spikes have also occurred in nonambush killings since 2014. Police leaders and researchers should monitor trends in ambush and nonambush killings of police, as the recent spikes may presage the emergence of a chronic problem.


1989 ◽  
Vol 1 (4) ◽  
pp. 301-306 ◽  
Author(s):  
Friedrich Buchholz ◽  
David J. Morris ◽  
Jonathan L. Watkins

A technique for moult staging Antarctic krill (Euphausia superba Dana) was used in the analysis of field samples to predict intermoult periods and hence assess growth and the effects of seasonal changes in food availability. The proportion of moulting krill was used, in conjunction with laboratory data on the duration of this phase, to predict the moulting frequency (intermoult period, IMP). The moulting frequency was then combined with appropriate daily growth increments from laboratory study to assess overall growth in the krill sampled. The effects of seasonal fluctuations in food availability on moulting frequency were examined for samples taken at five different locations and times of year. Moulting rate was not linearly related to the availability of phytoplankton, although it is likely that this factor has a marked effect. Similarly, although temperature affects IMP, the data indicate that this is not a simple relationship either. These preliminary data indicate the value of utilizing this technique in the analysis of field samples of Antarctic krill.


1979 ◽  
Vol 101 (4) ◽  
pp. 483-490 ◽  
Author(s):  
R. W. Miller

Today, technical experts in Europe and the U.S. are debating the merits of conducting new orifice flowmeter tests, establishing the effects of upstream disturbance and conducting other programs to improve orifice flowmetering accuracy. ISO has adopted a new “Universal” orifice equation proposed by J. Stolz. With over 1,000,000 orifice flowmeters in use today, any change in the coefficient value is of major concern. There are now two equations for calculating flange tap coefficients, the ASME-AGA equation and the ISO equation. They differ in form, predict different coefficients, and have different overall uncertainties (tolerance value). This paper presents a comparison between actual laboratory data and these two equations. The data were obtained in two high accuracy laboratories on flange tap orifice flowmeters fabricated by different manufacturers to AGA or ASME recommendations. Data plate dimensions were used in all calculations, and conformity to ASME or AGA requirements was the responsibility of the manufacturer. For this reason it is believed that the analysis more nearly represents what the user can expect if the in-site installation approached that of the laboratory. Results indicate that over the same beta ratio range the ISO (or Stolz) equation form is significantly better than the present ASME-AGA form. The overall uncertainty (or tolerance), although smaller than the ASME-AGA, is still ± 1 percent because of a 0.4 percent systematic error. Results of work by Miller-Kneisel, using data from three different laboratories, are presented to indicate that ±0.5 percent remains achievable; for betas up to 0.7 using the ISO (Stolz) equation form with modified coefficients.


1989 ◽  
Vol 75 (3) ◽  
pp. 222-225 ◽  
Author(s):  
Umberto Tirelli ◽  
Emanuela Vaccher ◽  
Vittorina Zagonel ◽  
Silvana Saracchini ◽  
Giulio Bertola ◽  
...  

The purpose of this report is to document and compare the presenting clinical and laboratory findings of 38 patients, all intravenous drug abusers, with pathologically documented persistent generalized lymphadenopathy (PGL), and of 50 patients with AIDS-unrelated malignant lymphoma (30 with Hodgkin's disease and 20 with non-Hodgkin's lymphoma). All patients, aged 40 years or less, consecutively seen since May 1984 in a single institution in Italy, have prospectively undergone a similar clinico-pathologic approach. In addition to a history of intravenous drug abuse and HIV serology, the results indicate that a history of infection in the previous year, night sweats, weight loss, generalized lymphadenopathy, β2 microglobuline, transaminase, T4/T8 ratio < 1, and polyclonal hypergamma-globulinemia significantly increased among PGL patients compared with patients with AIDS-unrelated malignant lymphoma. In contrast, patients with malignant lymphoma had a significant increase in mediastinal lymph nodes, sedimentation rate, LDH, fibrinogen and anemia. Therefore, at this time of an AIDS epidemic, after histologic diagnosis of reactive lymphadenopathy has been performed in young patients presenting with generalized lymphadenopathy, a request for a second biopsy and other invasive procedures may be avoided if clinical and laboratory data suggest a PGL syndrome. If not already performed, HIV antibody detection should be carried out in this setting.


2020 ◽  
Author(s):  
Catherine de Burgh-Day ◽  
Debbie Hudson ◽  
Oscar Alves ◽  
Morwenna Griffiths ◽  
Andrew Marshall ◽  
...  

&lt;p&gt;Extreme events such as droughts, heat waves and floods can have significant and long lasting financial, infrastructural and environmental impacts. While probabilistic seasonal outlooks are commonplace, there are relatively few probabilistic outlooks available on multiweek timescales. Additionally, many services focus on the middle of the distribution of possible outcomes &amp;#8211; e.g., forecasts of probability of above or below median, or probability of mean conditions exceeding some threshold. These do not encompass the types of extreme events that can be the most damaging, such as several consecutive days of extreme heat, unusually large numbers of cold days in a season, or an extended period where rainfall is in the lowest decile of historical years.&lt;/p&gt;&lt;p&gt;Advance warning of extreme events that impact particular industries enable managers to put in place response measures which can help to reduce their losses. This can involve:&lt;/p&gt;&lt;ul&gt;&lt;li&gt;Active responses which aim to reduce the severity of the impact. For example, losses in dairy production due to extreme heat can be mitigated by adjusting grazing rotations such that cows are in shadier paddocks during these events&lt;/li&gt; &lt;li&gt;Defensive responses which aim to account for any losses incurred due to an event. For example, the purchase of new farm equipment can be deferred if a forecast extreme event indicates a likely unavoidable financial loss in the near future&lt;/li&gt; &lt;/ul&gt;&lt;p&gt;To meet this need, the Australian Bureau of Meteorology is developing a suite of forecast products communicating risk of extreme events using data from the Bureau&amp;#8217;s new seasonal forecasting system ACCESS-S. Each prototype forecast product is trialed with external users through a webpage to assess usefulness and popularity.&lt;/p&gt;


2015 ◽  
Vol 38 (10) ◽  
pp. 1389-1413 ◽  
Author(s):  
Dmitry Tumin ◽  
Zhenchao Qian

Informal marital separation often quickly leads to divorce, but can become long-lasting, especially among disadvantaged populations. In this study, we focus on the timing of divorce after separating and examine how unemployment before or during separation affects this pivotal moment in the divorce process. Using data from the National Longitudinal Survey of Youth, 1979 Cohort ( N = 2,219), we track unemployment before and during separation and show that men’s unemployment during separation, rather than women’s, reduces the likelihood of divorce, independent of preseparation unemployment and other characteristics. For men, unemployment during a marital separation prolongs the divorce process, creating an extended period of uncertainty in marital relationships on the brink of dissolution. We discuss the gendered relationship observed between employment status during an informal separation and an estranged couple’s decision to complete the divorce process.


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