Brood Mortality and Egg Predation by the Nemertean, Carcinonemertes epialti, on the Yellow Rock Crab, Cancer anthonyi, in Southern California

1990 ◽  
Vol 47 (7) ◽  
pp. 1275-1281 ◽  
Author(s):  
Jeffrey D. Shields ◽  
Robert K. Okazaki ◽  
Armand M. Kuris
Keyword(s):  
Host Species ◽  
Southern California ◽  
Egg Mass ◽  
Minimal Impact ◽  
Egg Mortality ◽  
High Prevalence ◽  
Important Host ◽  
Rock Crab ◽  
Highly Correlated ◽  
Hemigrapsus Oregonensis

Carcinonemertes epialti had a minimal impact on the egg mortality of a lightly infested population of a commercially important crab host, Cancer anthonyi. The nemertean had a high prevalence (> 97%) but was found at low intensities (mean intensity = 86.5 worms/pleopod, mean density = 0.3 worms/1000 eggs). Egg mortality varied from 0.0–30.5%, and was highly correlated with both worm intensity, and the timing of crab embryogenesis (mean mortality = 5.7%). Separate sites within the pleopod experienced different causal mechanisms of mortality. Mortality at the base of the pleopod was correlated with the presence, abundance, and immigration of C. epialti. Mortality at the tip of the pleopod was less correlated with worm abundance and was most likely a result of abrasion to the eggs or egg mass. Infestations of C. epialti varied between seasons and between host species. The worm was more abundant on host species that bred year-round (Cancer anthonyi and Hemigrapsus oregonensis); hence, infestation dynamics varied markedly between host species. In southern California, Cancer anthonyi was virtually always infested with C. epialti and is the most important host for the worm in this area.

Novel Small Molecule Growth Inhibitors of Xanthomonas spp. Causing Bacterial Spot of Tomato

2021 ◽  
pp. PHYTO-08-20-034
Author(s):  
Vishal Srivastava ◽  
Loic Deblais ◽  
Dipak Kathayat ◽  
Francesca Rotondo ◽  
Yosra A. Helmy ◽  
...  
Keyword(s):  
Small Molecules ◽  
Untreated Control ◽  
Growth Inhibitors ◽  
Cell Integrity ◽  
Bacterial Spot ◽  
Beneficial Bacteria ◽  
Tomato Production ◽  
Minimal Impact ◽  
High Prevalence ◽  
Resistant Strains

Bacterial spot (BS) of tomato, caused by Xanthomonas gardneri, X. perforans, X. vesicatoria, and X. euvesicatoria, is difficult to control because of the high prevalence of copper- and streptomycin-resistant strains and the lack of resistance cultivars and effective bactericides. The objective of this study was to identify novel growth inhibitors of BS-causing Xanthomonas (BS-X) species by using small molecules (SM; n = 4,182). Several SMs (X1, X2, X5, X9, X12, and X16) completely inhibited the growth of BS-X isolates (n = 68 X. gardneri, 55 X. perforans, 4 X. vesicatoria, and 32 X. euvesicatoria) at ≥12.5 µM by disrupting Xanthomonas cell integrity through weakening of the cell membrane and formation of pores. These SMs were also effective against biofilm-embedded, copper- and streptomycin-resistant Xanthomonas strains while having minimal impact on other plant pathogenic (n = 20) and beneficial bacteria (n = 12). Furthermore, these SMs displayed equivalent antimicrobial activity against BS-X in seeds and X. gardneri in seedlings compared with conventional control methods (copper sulfate and streptomycin) at similar concentrations while having no detectable toxicity to tomato tissues. SMs X2, X5, and X12 reduced X. gardneri, X. perforans, X. vesicatoria, and X. euvesicatoria populations in artificially infested seeds ≤3.4-log CFU/seed 1 day postinfection (dpi) compared with the infested untreated control (P ≤ 0.05). SMs X1, X2, X5, and X12 reduced disease severity ≤72% and engineered bioluminescent X. gardneri populations ≤3.0-log CFU/plant in infected seedlings at 7 dpi compared with the infected untreated control (P ≤ 0.05). Additional studies are needed to increase the applicability of these SMs for BS management in tomato production.

scholarly journals Feline Foamy Virus is Highly Prevalent in Free-Ranging Puma concolor from Colorado, Florida and Southern California

Viruses ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 359 ◽  
Author(s):  
Sarah R. Kechejian ◽  
Nick Dannemiller ◽  
Simona Kraberger ◽  
Carmen Ledesma-Feliciano ◽  
Jennifer Malmberg ◽  
...  
Keyword(s):  
Southern California ◽  
Viral Infections ◽  
Puma Concolor ◽  
Foamy Virus ◽  
Significant Risk ◽  
Significant Risk Factor ◽  
Domestic Cat ◽  
Wild Populations ◽  
High Prevalence ◽  
Free Ranging

Feline foamy virus (FFV) is a retrovirus that has been detected in multiple feline species, including domestic cats (Felis catus) and pumas (Puma concolor). FFV results in persistent infection but is generally thought to be apathogenic. Sero-prevalence in domestic cat populations has been documented in several countries, but the extent of viral infections in nondomestic felids has not been reported. In this study, we screened sera from 348 individual pumas from Colorado, Southern California and Florida for FFV exposure by assessing sero-reactivity using an FFV anti-Gag ELISA. We documented a sero-prevalence of 78.6% across all sampled subpopulations, representing 69.1% in Southern California, 77.3% in Colorado, and 83.5% in Florida. Age was a significant risk factor for FFV infection when analyzing the combined populations. This high prevalence in geographically distinct populations reveals widespread exposure of puma to FFV and suggests efficient shedding and transmission in wild populations.

population ecology of the Australian frog Crinia signifera: egg-laying patterns and egg mortality

1994 ◽  
Vol 21 (6) ◽  
pp. 621 ◽  
Author(s):  
I Williamson ◽  
CM Bull
Keyword(s):  
Population Ecology ◽  
Water Body ◽  
Significant Variation ◽  
Hatching Success ◽  
Egg Laying ◽  
Egg Mass ◽  
Egg Mortality ◽  
Different Depths ◽  
Small Clusters ◽  
Overall Mortality

There are few studies of embryo mortality in anurans, and most of these studies deal with anurans that deposit clutches as one egg mass. In this study, egg mortality in Crinia signifera, an anuran that distributes its clutches in small clusters of eggs, was examined with the aims of: (i) determining overall mortality levels, and (ii) determining whether there was significant variation in success between clutches laid by different females. Hatching success varied significantly between years and between habitats, and was as low as 2% in some habitats in some years. Fungal infection caused most mortality, and hatching success was higher in temporary pools than in a permanent water body. Although significant variation in clutch success between females could occur if clutches were laid in different habitats or at different times, it was not clear whether there would be significant variation in clutch success between females laying simultaneously in the same water body. Differences in success of clutches might occur if females distributed eggs at different depths or in different-sized clusters. However, information on inter-female variation in these components of egg-laying behaviour in C. signifera is currently unavailable.

scholarly journals Short-interval fires and vegetation change in southern California

2021 ◽  
Author(s):  
Stephanie Ma Lucero ◽  
Nathan Emery ◽  
Carla M D'Antonio
Keyword(s):  
Los Angeles ◽  
Southern California ◽  
Vegetation Type ◽  
Short Interval ◽  
Tree Cover ◽  
Shrub Cover ◽  
Annual Grass ◽  
Sage Scrub ◽  
Highly Correlated ◽  
The Impact

Questions: In southern California, shortened fire return intervals may contribute to a decrease in native chaparral shrub presence and an increase in non-native annual grass presence. To test the hypothesis that short-fire return intervals promote a loss in shrub cover, we examined the contribution of single short-interval fires and abiotic conditions on the change of shrub cover within Ventura and Los Angeles counties. Through evaluating pre- and post-fire historical aerial images, we answered the following questions, 1) How has vegetation type cover changed after repeat fires? and 2) What landscape variables contribute the most to the observed change? Location: Ventura County and Los Angeles County, California, USA. Methods: We assessed the impact of a single short-interval fire by comparing vegetation recovery in adjacent once- and twice-burned fire burn polygons (long- and short-interval respectively). Pixel plots were examined within each polygon and vegetation cover was classified to vegetation type. We determined the best predictor of vegetation type cover with a linear mixed effects model comparison using Akaike Information Criterion. Results: Pre-fire and post-fire community type cover was highly correlated. Burn interval was the best predictor of tree cover change (lower cover in twice-burned pixel plots). Aspect was the best predictor of sage scrub cover change (greater cover on north-facing aspects). Years since fire was the best predictor of chaparral cover change (positive correlation) and sage scrub cover change (negative correlation). Conversion of chaparral to sage scrub cover was more likely to occur than conversion of chaparral to annual grass cover. Conclusions: Our study did not find extensive evidence of a decrease in chaparral shrub cover due to a single short-interval fire. Instead, post-fire cover was highly correlated with pre-fire cover. Chaparral recovery, however, was dynamic suggesting that stand recovery may be strongly influenced by local scale conditions and processes.

ESTIMATING THE NUMBER OF EGGS PER EGG MASS OF THE FOREST TENT CATERPILLAR, MALACOSOMA DISSTRIA, ON THREE TREE SPECIES IN THE SOUTHERN U. S.1,2

1987 ◽  
Vol 22 (2) ◽  
pp. 188-191 ◽  
Author(s):  
R. A. Goyer ◽  
G. J. Lenhard ◽  
J. D. Smith ◽  
R. A. May
Keyword(s):  
South Carolina ◽  
Tree Species ◽  
Malacosoma Disstria ◽  
Egg Mass ◽  
Nyssa Aquatica ◽  
Flowering Dogwood ◽  
Water Tupelo ◽  
Quercus Nigra ◽  
Highly Correlated ◽  
Water Oak

Several parameters of forest tent caterpillars (FTC), Malacosoma disstria Hübner, were evaluated for estimating the number of eggs per mass on three tree species in the southern U. S. Egg mass length without its spumaline (protective) coating was the most highly correlated measurement with actual number of eggs per mass on water tupelo, Nyssa aquatica L., water oak, Quercus nigra L., and flowering dogwood, Cornus florida L. Fecundity was significantly higher on water tupelo in Louisiana than on water oak and flowering dogwood in South Carolina.

A one year prevalence study of schizophrenia on Reunion Island

1997 ◽  
Vol 12 (6) ◽  
pp. 284-288 ◽  
Author(s):  
M Jay ◽  
P Gorwood ◽  
J Feingold ◽  
M Leboyer
Keyword(s):  
Prevalence Study ◽  
Limited Area ◽  
Reunion Island ◽  
High Prevalence ◽  
Range Difference ◽  
Réunion Island ◽  
The Indian Ocean ◽  
Highly Correlated ◽  
One Year ◽  
Low Prevalence

SummaryReview of geographical comparisons of the prevalence of schizophrenic disorders found a ten-fold range difference between geographical contiguous groups, with high and low prevalence pockets. We performed a 1-year prevalence study of schizophrenia in a limited area of Reunion Island in the Indian Ocean, and analysed the prevalence variability in contiguous regions of this area. We found one of the highest reported age-corrected (above 15 years) 1-year prevalence of schizophrenia (14.9 per thousand). Large discrepancies in the distribution of prevalence rates of schizophrenia were observed between the five towns analysed. Interestingly, when a higher prevalence was observed, it was highly correlated with an increase of the percentage of familial cases (r = 0.989, df = 3, P = 0.0014). Presence of founder effect often described in geographical isolates could explain the high prevalence rate and the heterogeneity between towns observed in our sample.

scholarly journals Prevalence of antibodies against Lawsonia intracellularis in dogs with and without gastrointestinal disease

2008 ◽  
Vol 52 (No. 11) ◽  
pp. 502-506 ◽  
Author(s):  
J. Klimes ◽  
K. Dezorzova ◽  
J. Smola ◽  
R. Husnik
Keyword(s):  
Host Species ◽  
Gastrointestinal Disease ◽  
Antibody Test ◽  
Igg Antibodies ◽  
Lawsonia Intracellularis ◽  
Important Host ◽  
Specific Igg ◽  
Indirect Immunofluorescent ◽  
Immunofluorescent Antibody Test ◽  
Specific Igg Antibodies

Blood sera from 71 dogs were examined for specific IgG antibodies against <I>Lawsonia intracellularis</I> using the indirect immunofluorescent antibody test. The dogs were divided into two groups according to the presence or absence of gastrointestinal disease, which could potentially be associated with <I>L. intracellularis</I>. In the group of dogs with gastrointestinal disease (<I>n</I> = 54), 40 dogs were positive (74.1%). Most positive dogs suffered from chronic or intermittent diarrhoea. In the group without signs of primary gastrointestinal disease (<I>n</I> = 17), antibodies were found in 13 dogs (76.5%). The overall positivity was 74.7%. These results indicate that dogs may be an important host species of <I>L. intracellularis</I>.

scholarly journals Estimating the Prevalence of Ovarian Cancer Symptoms in Women Aged 50 Years or Older: Problems and Possibilities

2016 ◽  
Vol 184 (9) ◽  
pp. 670-680 ◽  
Author(s):  
Zhuoyu Sun ◽  
Lucy Gilbert ◽  
Antonio Ciampi ◽  
Jay S. Kaufman ◽  
Olga Basso
Keyword(s):  
Ovarian Cancer ◽  
Older Women ◽  
High Frequency ◽  
Diagnostic Testing ◽  
Inverse Probability Weighting ◽  
Probability Weighting ◽  
Minimal Impact ◽  
Cancer Symptoms ◽  
Inverse Probability ◽  
High Prevalence

Abstract Diagnostic testing is recommended in women with “ovarian cancer symptoms.” However, these symptoms are nonspecific. The ongoing Diagnosing Ovarian Cancer Early (DOVE) Study in Montreal, Quebec, Canada, provides diagnostic testing to women aged 50 years or older with symptoms lasting for more than 2 weeks and less than 1 year. The prevalence of ovarian cancer in DOVE is 10 times that of large screening trials, prompting us to estimate the prevalence of these symptoms in this population. We sent a questionnaire to 3,000 randomly sampled women in 2014–2015. Overall, 833 women responded; 81.5% reported at least 1 symptom, and 59.7% reported at least 1 symptom within the duration window specified in DOVE. We explored whether such high prevalence resulted from low survey response by applying inverse probability weighting to correct the estimates. Older women and those from deprived areas were less likely to respond, but only age was associated with symptom reporting. Prevalence was similar in early and late responders. Inverse probability weighting had a minimal impact on estimates, suggesting little evidence of nonresponse bias. This is the first study investigating symptoms that have proven to identify a subset of women with a high prevalence of ovarian cancer. However, the high frequency of symptoms warrants further refinements before symptom-triggered diagnostic testing can be implemented.

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