scholarly journals Mark-recapture estimates of daily survival rates of two damselflies (Coenagrion puella and Ischnura elegans)

2001 ◽  
Vol 79 (5) ◽  
pp. 895-899 ◽  
Author(s):  
Bradley R Anholt ◽  
Christoph Vorburger ◽  
Peter Knaus
Keyword(s):  
Sex Ratio ◽  
Survival Rates ◽  
Breeding Site ◽  
Immature Stage ◽  
Differential Survival ◽  
Mark Recapture ◽  
Probability Of Survival ◽  
Ischnura Elegans ◽  
History Of ◽  
Capture History

Male-biased operational sex ratios are very common in sexually mature dragonflies. These may be due to differential survival or differences in time spent at the breeding site by the sexes. Because most studies are carried out at the breeding site, these two processes can be measured as survival rates or recapture rates using modern capture–mark–recapture methods. We marked 66 female and 233 male Coenagrion puella, and 137 female and 347 male Ischnura elegans during three capture periods spread over 18 days. Each time an animal was recaptured it was re-marked so that the capture history of any captured animal could be readily identified. We recaptured 131 C. puella and 55 I. elegans at least once. We used the Cormack–Jolly–Seber model to estimate the daily probability of survival and recapture. The probability of recapture was, on average, more than three times higher for male C. puella (0.489) than females (0.133) with significant day to day variation. The daily probability of survival did not differ significantly between the sexes (0.860), with no significant variation among days. In contrast, in I. elegans the probability of recapture did not differ between the sexes (0.139 for the first 5 days; between 0.032 and 0.287 for the final 3 days), but the daily probability of surviving was much higher for males (0.812) than for females (0.579). Assuming that the sex ratio was unity at sexual maturity, the recapture and survival rates predicted well the sex ratio of the sample of C. puella but predicted more males than were observed in the sample of I. elegans. This suggests that male I. elegans may suffer higher mortality than females in the immature stage.

scholarly journals Mark-recapture estimates of daily survival rates of two damselflies (Coenagrion puella and Ischnura elegans)

2001 ◽  
Vol 79 (5) ◽  
pp. 895-899 ◽  
Author(s):  
Bradley R. Anholt ◽  
Christoph Vorburger ◽  
Peter Knaus
Keyword(s):  
Survival Rates ◽  
Mark Recapture ◽  
Ischnura Elegans ◽  
Daily Survival

Common vole (Microtus arvalis) population sex ratio: biases and process variation

2005 ◽  
Vol 83 (11) ◽  
pp. 1391-1399 ◽  
Author(s):  
Josef Bryja ◽  
Jiřina Nesvadbová ◽  
Marta Heroldová ◽  
Eva Jánová ◽  
Jan Losík ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Process Variation ◽  
Methodological Approach ◽  
Survival Rates ◽  
Common Vole ◽  
Joint Effect ◽  
Microtus Arvalis ◽  
Differential Survival ◽  
Capture Recapture ◽  
Error Bias

Vole population sex ratio varies seasonally. However, population sex ratios have usually been estimated using naïve estimators that do not allow for biases owing to the sex difference in capture probabilities and movement distances (i.e., effective areas sampled). Here we aimed to advance the methodological approach, recognizing that there are two different classes of contributing mechanisms to the pattern which are best addressed separately: (1) those mechan isms imposing a systematic error (bias) in population estimates and (2) those generating the true process variation. Analyzing 7-year capture–recapture data in the common vole (Microtus arvalis (Pallas, 1778)), we quantified both types of biases and revealed that the bias owing to differential capture rates was often severe and less predictable, whereas that owing to differential effective areas was smaller and overestimated male numbers for most of the year. We demonstrated unambiguously that the unbiased population sex ratio indeed varies seasonally, with the males usually being more numerous over winter and spring. By testing predictions from two mechanistic hypotheses to explain the process variability, we found evidence for both the differential recruitment hypothesis and the differential survival hypothesis. From April–May to August, it was the females that were recruited more to the population and that had higher survival rates than males. We suggest that the seasonal variation in the population sex ratio is not merely a result of biasing mechanisms but an important population property driven by the joint effect of differential recruitment and differential survival between sexes.

Primary squamous cell carcinoma of the ampulla of Vater: management and review of the literature

2021 ◽  
Vol 14 (1) ◽  
pp. e236477
Author(s):  
Subhash Soni ◽  
Poonam Elhence ◽  
Vaibhav Kumar Varshney ◽  
Sunita Suman
Keyword(s):  
Squamous Cell Carcinoma ◽  
Cell Carcinoma ◽  
Squamous Cell ◽  
Survival Rates ◽  
Ampulla Of Vater ◽  
Metallic Stent ◽  
Biological Behaviour ◽  
Curative Intent ◽  
Term Survival ◽  
History Of

Squamous cell carcinoma (SCC) of the ampulla of Vater is a rare pathology and only few cases are reported in the literature. With limited experience of primary SCC in the ampulla of Vater, its biological behaviour, prognosis and long-term survival rates are not well known. A 38-year-old woman presented with a history of painless progressive jaundice for which self-expending metallic stent was placed 3 years back. She was evaluated and initially diagnosed as probably periampullary adenocarcinoma. She underwent pancreaticoduodenectomy and histopathology with immunohistochemistry was suggestive of SCC of ampulla of Vater. She received adjuvant chemotherapy and doing well with no recurrence after 1 year of follow-up. In conclusion, SCC of the ampulla is an unusual pathology that should be kept as a differential diagnosis for periampullary tumours. Surgical treatment with curative intent should be performed whenever feasible even in the setting of bulky tumour to improve the outcome.

Inbreeding depression and floral type fitness differences in Viola canadensis (Violaceae), a species with chasmogamous and cleistogamous flowers

2000 ◽  
Vol 78 (11) ◽  
pp. 1420-1429 ◽  
Author(s):  
Theresa M Culley
Keyword(s):  
Inbreeding Depression ◽  
Survival Rates ◽  
Early Life History ◽  
Flower Number ◽  
Life History Stages ◽  
The North ◽  
History Of ◽  
Vegetative Biomass ◽  
Similar Survival ◽  
Cross Type

Few studies of inbreeding depression have focused on species producing both showy, chasmogamous (CH) flowers and self-pollinated, cleistogamous (CL) flowers. The goals of this investigation were to measure the level of inbreeding depression in the North American violet, Viola canadensis L., and to determine if any fitness differences were linked to floral type (CH versus CL) rather than to cross type (self versus outcross). Hand pollinations were carried out to produce self- and outcross-pollinated CH progeny, and CL seeds were also collected. In a greenhouse, selfed and outcrossed CH flowers produced similar numbers of seeds, and both types of progeny had similar survival rates and comparable numbers of CH flowers, although outcrossed CH progeny had 14% greater vegetative biomass than selfed CH progeny. The level of inbreeding depression in V. canadensis was low, indicating that there may be few drawbacks to selfing in this species. A comparison of CL and self-pollinated CH progeny showed that, although there were differences in CH flower number, overall fitness differences were minimal. The similar performance of selfed (CL and CH) and outcrossed progeny in early life-history stages of V. canadensis suggests a history of inbreeding in the population.Key words: cleistogamy, inbreeding depression, outcrossing, selfing, Viola canadensis.

The Life-History of Badumna-Candida (Araneae, Amaurobioidea)

1993 ◽  
Vol 41 (5) ◽  
pp. 441 ◽  
Author(s):  
MF Downes
Keyword(s):  
Sex Ratio ◽  
Egg Production ◽  
Production Cycle ◽  
Social Spider ◽  
Social Spiders ◽  
Primary Sex Ratio ◽  
The Social ◽  
The Status ◽  
History Of ◽  
Changes Over Time

A two-year study of the social spider Badumna candida at Townsville, Queensland, provided information on colony size and changes over time, maturation synchrony, temperature effects on development, sex ratio, dispersal, colony foundation, fecundity and oviposition. Key findings were that B. candida outbred, had an iteroparous egg-production cycle between March and October, had an even primary sex ratio and achieved maturation synchrony by retarding the development of males, which matured faster than females at constant temperature. There was no overlap of generations, the cohort of young from a nest founded by a solitary female in summer dispersing the following summer as subadults (females) or subadults and adults (males). These findings confirm the status of B. candida as a periodic-social spider (an annual outbreeder), in contrast to the few known permanent-social spider species whose generations overlap. Cannibalism, normally rare in social spiders, rose to 48% when spiders were reared at a high temperature. This may be evidence that volatile recognition pheromones suppress predatory instincts in social spiders.

Differences in transitions of care among cancer patients with and without venous thromboembolism (VTE) events.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e18636-e18636
Author(s):  
Cinduja Nathan
Keyword(s):  
Venous Thromboembolism ◽  
Patient Care ◽  
Cancer Patients ◽  
Cancer Diagnosis ◽  
Medical Center ◽  
Survival Rates ◽  
Transitions Of Care ◽  
Office Visits ◽  
Oncology Patient ◽  
History Of

e18636 Background: Transitions of care are an important part of medical care, as they provide opportunities to address patient concerns, refine goals to match current needs and prevent unforeseen complications and comorbidities. One such common and prevalent comorbidity amongst cancer patients is venous thromboembolism (VTE) events. Common VTE events include the occurrence of pulmonary embolism (PE), deep vein thrombosis (DVT) or both at the time of diagnosis or any time thereafter. It is estimated that approximately 4–20% of cancer patients will experience a VTE. Cancer patients developing VTE is a serious concern as it can adversely affect the patients’ quality of life and reduce overall survival rates and prognosis. Methods: This study is designed as a case control study. The subject group consists of 87 cancer patients who had one or several VTE events after their cancer diagnosis. Patients were selected from the UVM Medical Center electronic health record database. The goal of this project was to quantify and compare the average number of transitions of care in cancer patients with and without venous thromboembolism (VTE) events. This was achieved by reviewing the patients charts three months following a VTE event and evaluating whether these patients had a greater number of transitions compared to the three months prior to their VTE event. Transitions of care in our study were defined as office visits, ED visits, and inpatient admissions related to their VTE. Results: Initial evaluation of the results showed that there were more transitions of care amongst cancer patients with a VTE than without. Preliminary data of the 87 patients shows that patients who developed a VTE event after their cancer diagnosis had on average 1.3 more transitions of care within the three months following their VTE event compared to cancer patients without a VTE event. A t test will be used to determine whether the difference between the means (number of transitions of care) of the two groups (cancer patients with VTE and those without VTE) is significant. Conclusions: The implications of having greater transitions of care amongst cancer patients with VTE events are profound. Having more transitions of care exemplifies better implementation, patient care and involvement of health care teams given a history of VTE. Furthermore, the results of this study will provide further insight on ways to improve clinical outcomes and oncology patient care given a history of VTE.

Population dynamics of Stenothoe valida Dana, 1852 (Amphipoda, Stenothoidae) at Cheongsapo beach of Busan, Republic of Korea

Crustaceana ◽  
2021 ◽  
Vol 94 (4) ◽  
pp. 413-429
Author(s):  
Ye Ji Lee ◽  
Won Gyu Park
Keyword(s):  
Population Dynamics ◽  
Life History ◽  
Sex Ratio ◽  
Brood Size ◽  
Ovigerous Female ◽  
Seasonal Pattern ◽  
Recruitment Rate ◽  
Republic Of Korea ◽  
Female Size ◽  
History Of

Abstract The population dynamics of Stenothoe valida Dana, 1852 were studied at Cheongsapo beach of Busan, Republic of Korea, from March 2019 to March 2020. Sampling was conducted once a month at low tide during spring tides. Specimens were grouped by the cephalic length at 0.025 mm intervals, and classified into four categories: females, ovigerous females, males and juveniles. The sex ratio, defined as females : total males + females, exceeded 0.5 during most of the study period. Brood size was significantly coupled with ovigerous female size. Two to four cohorts appeared at each study period. New cohorts occurred at almost every sampling except in the samples Jun-2, and Nov-2. Life span was estimated at 1-2 months. The juvenile ratio, the ratio of ovigerous females, and the recruitment rate estimated by FiSAT were commonly high in summer and winter. The life history of S. valida was not coupled with water temperature, but had a strong seasonal pattern.

scholarly journals Occurence and biological aspects of the clitoria tree psyllid in Brazil

2005 ◽  
Vol 62 (3) ◽  
pp. 281-285 ◽  
Author(s):  
Manoel Guedes Corrêa Gondim Junior ◽  
Reginaldo Barros ◽  
Fernando Rodrigues da Silva ◽  
Geraldo José Nascimento de Vasconcelos
Keyword(s):  
Sex Ratio ◽  
Incubation Period ◽  
Development Time ◽  
Metropolitan Areas ◽  
Immature Stage ◽  
Frequency Curve ◽  
Nymphal Stage ◽  
Female Longevity ◽  
Biological Aspects

Clitoria fairchildiana (Howard) is a tree largely distributed in Brazil, used for urban arborization. In April 2001, the psyllid Euphalerus clitoriae Burckhardt & Guajará was reported on this plant in the metropolitan areas of Recife, PE, Brazil. This report records the occurrence of E. clitoriae and studies some of its biological aspects in this area. With this purpose, C. fairchildiana leaves were sampled weekly, and E. clitoriae nymphs as well as Aprostocetus sp. larvae and nymphs were collected and counted. The E. clitoriae population ranged from 2 to 90 nymphs per leaflet. The Aprostocetus sp. percentage of parasitism ranged from 3 to 24%. The frequency curve for pygidium width ranged from 120 to 140; 200 to 240; 300 to 380; 460 to 580, and 720 to 820 mm for the first, second, third, fourth, and fifth instars, respectively. The incubation period for E. clitoriae eggs lasted 7.6 days. The nymphal stage lasted 5.7; 4.5; 4.8; 5.0, and 6.1 days for the first, second, third, fourth, and fifth instars, respectively. Development time from egg to adult was 33.7 days. Female longevity 8.6 days, with a daily fecundity of 118 eggs. The total viability of the immature stage was 74%, and the sex ratio was 0.5.

scholarly journals Descriptive analysis of 192 cases of breast cancer occurring before age 40 in Yaounde, Cameroon

2017 ◽  
Vol 6 (7) ◽  
pp. 2704 ◽  
Author(s):  
Félix Essiben ◽  
Pascal Foumane ◽  
Esther JNU Meka ◽  
Michèle Tchakounté ◽  
Julius Sama Dohbit ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Ductal Carcinoma ◽  
Early Stage ◽  
Descriptive Analysis ◽  
Survival Rates ◽  
The United States ◽  
Therapeutic Modalities ◽  
History Of ◽  
Case Files ◽  
Common Histological Type

Background: Breast cancer is today a global health problem. With 1,671,149 new cases diagnosed in 2012, it is the most common female cancer in the world and accounts for 11.9% of all cancers and it affects more people than prostate cancer. In 2008, The United States statistics showed that, for all cancer that affect women before 40 years, more than 40% of them concerned the breast. The aim of this study was to describe the clinical, histopathological and therapeutic aspects of breast cancer in women under 40 years of age in Yaoundé.Methods: This was a retrospective study with data collected from 192 medical case files of women treated over a period of 12 years, from January 2004 to December 2015 at the Yaounde General Hospital and the Yaounde Gyneco-Obstetric and Pediatric Hospital. Microsoft Epi Info version 3.4.5 and SPSS version 20.0 softwares were used for data analysis.Results: From 2004 to 2015, 1489 cases of breast cancer were treated in both hospitals. Of these, 462 women were less than 40 years old, representing a proportion of 31.0%. The mean age at diagnosis was 33.5±5.0 years and 17.7% of women had a family history of breast cancer. The average time before an initial consultation was 6.7±6.6 months.  Most cases were classified as T4 (46.1%). The most common histological type was ductal carcinoma (87.4%). Grades SBR II and SBR III were predominant (76.4%). Axillary dissection (64.4%) and neoadjuvant chemotherapy (43.9%) were the main therapeutic modalities. The overall survival rate at 5 years was 51.2%. Five-year survival rates with no local recurrence and no metastatic occurrence were 35.8% and 43.2% respectively.Conclusions: Breast cancer largely affects women under the age of 40 and is often discovered late, at an advanced stage. The prognosis appears poor. Only screening could facilitate diagnosis at an early stage of the disease for better outcomes.

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