Estimating survival rates of black bears

1998 ◽  
Vol 76 (7) ◽  
pp. 1335-1343 ◽  
Author(s):  
Vanessa A Sorensen ◽  
Roger A Powell

Capture-recapture, radiotelemetry (on a monthly and a yearly basis), and age-distribution methods were used to estimate annual survival rates for black bears (Ursus americanus) in the southern Appalachians from 1981 to 1996. Using capture-recapture data, the Jolly-Seber estimator calculated the annual survival rate for all bears over all years to be 0.64 ± 0.04 (mean ± SE). Because of small sample sizes, this method did not produce yearly estimates or allow separation of the data into age or sex classes. Both the Kaplan-Meier estimator (using monthly telemetry data) and the percent survival estimator (using yearly telemetry data) computed an overall annual survival rate of 0.76 ± 0.04. Survival rates for the early years of the study (1981-1987) were significantly lower than in the late years (1988-1996). No significant difference in survival rate was detected between the sexes or among age-classes. Because it is difficult to capture and recapture large numbers of animals, radiotelemetry methods are preferable for large mammals such as black bears. If bears wear their collars for at least a year, calculating survival from yearly telemetry data provides a good estimate of bear survival. Using monthly telemetry data, however, provided the most detailed understanding of bear survival. Survival estimates produced by the age-distribution method were unreliable.

2017 ◽  
Vol 28 (1) ◽  
pp. 145-156 ◽  
Author(s):  
YANFANG LI ◽  
XINPING YE ◽  
MIN WANG ◽  
XIA LI ◽  
RONG DONG ◽  
...  

SummaryA reintroduction project for the endangered Crested Ibis Nipponia nippon was conducted in Ningshan County (Shaanxi Province) on May 31, 2007. Post-release monitoring of the survival of the reintroduced population was carried out extensively from 2008 to 2015. Data collected over eight years after release were used to estimate the annual survival rate for different cohorts using a Cormack-Jolly-Seber model with capture-recapture data. The mean annual survival rates for all individuals were estimated to be 0.738 (95% CI: 0.547–0.801) and 0.752 (95% CI: 0.478–0.887) for released birds. For different age classes in the recipient population, the survival rates were estimated to be 0.384 (95% CI: 0.277–0.504), 0.853 (95% CI: 0.406–0.978), and 0.812 (95% CI: 0.389–0.950) for yearlings, juveniles and adults, respectively. The higher mortality for yearlings has greatly decreased the survival rate and our focal population was indeed sensitive to changes in yearling survival. Therefore, effective protection of yearlings was crucial to population persistence, as well as to juveniles and adults. The large proportion of mature individuals in our focal population indicated a gradually growing population. There was a slight bias towards males in the adult sex ratio with the increase of wild-born offspring, but it was not statistically significant. Therefore, we conclude that the primary goal of establishing a self-sustaining population of the Crested Ibis in part of their historical range has been achieved. Finally, we discuss factors affecting the survival of the reintroduced population and we propose some changes for future management of endangered species.


2019 ◽  
Vol 26 (1) ◽  
pp. 107327481986527 ◽  
Author(s):  
Thang Vu Hong ◽  
Duc Nguyen Ba ◽  
Lambert Skoog ◽  
Van Ta Thanh ◽  
Edneia Tani

Little is known about breast cancer in Vietnamese women. Previous studies have reported the frequencies of prognostic factors of breast cancer in this population. The aim of this study was to examine the prognostic factors associated with the survival rates of patients with breast cancer treated at the National Cancer Hospital, Hanoi, Vietnam. We recruited 248 women with operable breast cancer treated with surgery and adjuvant therapy. Tumor tissue samples were stained by many immunohistochemical approaches and analyzed for estrogen receptor, progesterone receptor, and HER2 gene amplification status. A Cox model was used to determine the relationship between survival and the prognostic factors. The disease-free survival rate, overall survival rate, and cancer-specific survival rate were 75.8%, 80.6%, and 86.4%, respectively, at 5 years and 62.3%, 68.1%, and 78.9%, respectively, at 10 years. The lung was the most common metastatic site. Women with factors associated with a poor prognosis (eg, advanced clinical stage, high tumor grade, progesterone receptor [PR] negativity, HER2 amplification) had significantly lower survival rates. Patients with PR-negative breast cancer had significantly worse survival rates compared to those who were PR positive, according to multivariate analysis (hazard ratio = 1.77, 95% confidence interval: 1.01-3.11, P = .045); however, there was only a statistically significant difference in postmenopausal patients. The PR was a prognostic factor in postmenopausal women with breast cancer, but not in premenopausal women.


2001 ◽  
Vol 28 (6) ◽  
pp. 565 ◽  
Author(s):  
Richard E. Major ◽  
Greg Gowing

To determine relative survival rates of small birds occupying small, linear strips of woodland compared with large patches of woodland, marked populations of red-capped robins were monitored over a two-year period. In total, 196 male robins were banded with unique colour combinations in 10 woodland remnants and censused by song playback at half-yearly intervals. The Cormack–Jolly–Seber method was used to calculate half-yearly survival probabilities for birds in the two habitat configurations and the strongest model included separate survival parameters for summer (36.2% 5.1) and autumn (88.9% 13.5) half-years, but a constant recapture probability (50.5% 7.2). The inclusion of separate parameters for the large and linear habitat configurations reduced the strength of the model, indicating that there was no significant difference between the survival rates of birds occupying small, linear strips of woodland and birds occupying large patches of woodland. The mean annual survival, determined by multiplying the half-yearly survival probabilities, was 32%, which is low, compared with the annual survival of other Petroica robins. Although no banded birds were located away from the banding site, we suspect that much of the ‘mortality’ represented emigration during the summer half-year. Under this scenario a better estimate of annual survival (79%) might be achieved by extrapolation of survival over the winter half-year. This study provides no data to support the contention that adult mortality is higher in small, linear strips of habitat, although further data on the fate of birds that disappear from remnants is required before this is conclusive. In addition, to detect a 20% difference in survival using similar methods to the present study, with their accompanying sources of variation, at least 10 times the number of birds would need to be monitored. This might most effectively be done as a co-operative banding project.


1994 ◽  
Vol 3 (5) ◽  
pp. 337-341 ◽  
Author(s):  
D Willms ◽  
M Nield ◽  
I Gocka

BACKGROUND: Published reports indicate that survival rates of patients with adult respiratory distress syndrome have not improved dramatically since the first report of the condition in 1967. However, changes in ventilator strategies and improved critical care management may result in better survival rates in patients with well-defined, severe adult respiratory distress syndrome. OBJECTIVES: To report the outcomes of patients with adult respiratory distress syndrome treated in a community hospital and compare these findings with those in previously published reports. METHODS: A retrospective study design was used. All patients diagnosed with adult respiratory distress syndrome (N = 47) over a 2-year period were studied. RESULTS: For the study patients, the survival rate was 64%; 29% died from respiratory failure alone. Analysis demonstrated that advanced age was not associated with mortality. Pressure-control ventilation was used for 31 patients and there was no significant difference in the presence of barotrauma in the pressure-control mode vs volume ventilation. CONCLUSION: This survival rate exceeds most recently reported rates and thus supports the idea that improvement in treatment of adult respiratory distress syndrome is occurring.


Author(s):  
Hsiao ◽  
Chen ◽  
Meir ◽  
Tan ◽  
Hsiao ◽  
...  

To determine the comparative efficacy and safety of penetrating keratoplasty (PK) and Descemet stripping automated endothelial keratoplasty (DSAEK) in the Asian population receiving imported donor corneas, our single-center retrospective study provides analysis supporting the transition from PK to DSAEK in the Asian population using imported American donor corneas. We analyzed 259 patients with 241 and 57 cases of PK and DSAEK respectively during 2008 to 2017 using imported corneas at Chang Gung Memorial Hospital, Linkou, Taiwan. In terms of long-term graft survival analysis, there was no difference between PK and DSAEK (log-rank p = 0.386, HR = 0.920, 95% CI: [0.641–1.380]). However, Cox proportional regression analysis revealed that corneal survival rate of DSAEK group in the first 100 days after transplantation was inferior than that of PK group (log-rank p < 0.001, HR = 2.733, 95% CI: [1.501–4.977])]. Despite the inferior survival rate, there were significantly less neovascularization and Descemet membrane folds in the DSAEK group. Importantly, the non-complication rate of DSAEK was much higher than that of PK with significant difference (PK, 25.7% vs DSAEK 42.0%, p = 0.022). Collectively, DSAEK is suggested as an alternative surgical modality in Asian patients using imported American donor corneas because of less complication, and no difference in long-term corneal graft survival rates between PK and DSAEK.


Zygote ◽  
2017 ◽  
Vol 25 (3) ◽  
pp. 288-295 ◽  
Author(s):  
Arthur Vinícius Lourenço Ferreira ◽  
Moisés Fernandes Martins ◽  
Míriam Luzia Nogueira Martins de Sousa ◽  
Aldeney Andrade Soares Filho ◽  
Célia Maria de Souza Sampaio

SummaryCooling techniques have several applications for reproduction in aquaculture. However, few studies have sought to create protocols for cooling and cryopreservation of Macrobrachium amazonicum embryos. Thus, the objective of this work was to verify the survival of M. amazonicum embryos and the correlation between embryonic volume and mortality of M. amazonicum embryos after cooling. Embryo pools were collected from three females and divided into two treatment groups: dimethyl sulfoxide (DMSO) 3% and ethylene glycol (EG) 0.5%, both of them associated with 2 M sucrose. Positive and negative control groups consisted of seawater 10%. Aliquots of 10 µg of embryos were placed in Falcon® tubes containing a cryoprotectant solution and submitted directly to the test temperature of 2°C for 2 and 6 h of cooling. Further analysis of survival and embryonic volume were performed under a stereoscopic microscope. Data were subjected to analysis of variance (ANOVA), and means were compared using the Tukey test at 5%. The highest embryonic survival rate was observed after the shortest storage time for both the DMSO 3% and the 0.5% EG groups, with survival rates of 84.8 ± 3.9 and 79.7 ± 2.8%, respectively. There was a reduction in survival after 24 h, with the DMSO 3% group presenting a survival rate of 71.7 ± 6.6%, and the EG 0.5% group, 66 ± 6.9%. Survival showed a statistically significant difference when compared with the positive controls after 2 h and 24 h of cooling, with 99 ± 0.5% and 95.8 ± 1.5% survival rates, respectively. There was no significant statistical difference in the embryonic volume, but it was possible to observe a change in the appearance of the embryos, from a translucent coloration to an opaque white or brownish coloration, after 24 h in incubators. Thus, it can be concluded that survival is inversely proportional to storage time and that, although there was no change in the embryonic volume after cooling, a change in the appearance of embryos could be observed.


2002 ◽  
Vol 20 (22) ◽  
pp. 4459-4465 ◽  
Author(s):  
Hyo-Suk Lee ◽  
Kang Mo Kim ◽  
Jung-Hwan Yoon ◽  
Tae-Rim Lee ◽  
Kyung Suk Suh ◽  
...  

PURPOSE: Identifying a special subgroup of hepatocellular carcinoma (HCC) patients who may benefit from transcatheter arterial chemoembolization (TACE) when compared with the standard treatment of hepatic resection (HR) warrants research in Asian countries. PATIENTS AND METHODS: From January 1993 to December 1994, 182 patients with operable HCC (Child-Pugh class A and International Union Against Cancer [UICC] stage T1-3N0M0) were enrolled. After initial TACE and lipiodol computed tomography, 91 received HR and 91, who refused the operation, received repeated sessions of TACE. After stratification according to the tumor stage (UICC and Cancer of the Liver Italian Program [CLIP]) and lipiodol retention pattern, the survival rates of the two treatment groups were compared. The median follow-up period was 83 months. RESULTS: As of December 31, 2000, 48 patients who underwent HR and 68 patients who underwent TACE had died. In a subgroup analysis according to tumor stage, the HR group survival rate was significantly higher than the TACE group in both UICC T1-2N0M0 (P = .0058) and CLIP 0 (P = .0027) subgroups. However, there was no significant difference in either UICC T3N0M0 (P = .7512) or CLIP 1-2 (P = .5366) subgroups. Even in patients with UICC T1-2N0M0 HCC, when lipiodol was compactly retained, the survival rate of the HR group was comparable to that of the TACE group (P = .0596). CONCLUSION: TACE proved to be as effective as HR in the subpopulations with UICC T3N0M0 or CLIP 1-2 HCC and adequate liver function, and even with UICC T1-2N0M0 HCC when lipiodol was compactly retained in the tumor. In such cases, the choice of treatment modality between TACE and HR may be left to the patient’s preference.


2011 ◽  
Vol 29 (4_suppl) ◽  
pp. 625-625
Author(s):  
M. Omaira ◽  
M. Mozayen ◽  
K. Katato

625 Background: Surgical resection of local colon cancer is the only curative treatment, at the same time adjuvant chemotherapy is clearly shown to be beneficial as the standard of care for node positive disease (stage III) colon cancer. However the role of chemotherapy for stage II colon cancer treatment is still conflicting. We aim to compare the overall survival rate of stage II colon cancer patient's with and without chemotherapy. Methods: A retrospective observational study was conducted from 1990-2006. Patients with stage II colon cancer were included. Patient's characteristics including age, gender, common site of involvement, histology patterns, overall survival rate and treatment with chemotherapy were recorded. Results: A total of 138 consecutive patients were identified from 1990-2006. The median age was 68 (21-91) year, males (44%), African Americans (47.6%). The most common sites of the primary tumor were sigmoid and cecum (22.4%) each. Adenocarcinoma being the most common pathology. Majority of the patients (86.2%) were found to have T 3 tumors. Of the patients that received chemotherapy (29/44) 66% had an overall survival rate of three years or more, whereas (53/94) 57% of the patients who did not receive chemotherapy had a survival rate of three years or more. The difference of survival rates between the two groups of patients was not statistically significant. Conclusions: The role of chemotherapy in stage II colon ancer is still controversial. There was no significant difference in overall survival between the two groups who did and did not receive chemotherapy; thus more studies are warranted to explore the factors that predict the survival of stage II colon cancer. No significant financial relationships to disclose.


2019 ◽  
Vol 37 (4_suppl) ◽  
pp. 288-288
Author(s):  
Phani Keerthi Surapaneni ◽  
Zhuo Li ◽  
Lalitha Padmanabha Vemireddy ◽  
Pashtoon Murtaza Kasi ◽  
Jason Scott Starr ◽  
...  

288 Background: Obesity is a risk factor for developing cholangiocarcinoma (CCA). However, the effect of obesity on survival of CCA is unclear. The primary aim of this study was to analyze the impact of obesity upon overall survival of CCA patients. Secondary aims were to analyze impact of obesity upon other disease characteristics such as tumor site, stage, age, sex, BMI and Ca 19-9. Methods: A total of 411 unique pts diagnosed with CCA at Mayo Clinic Florida between 2000 and 2018 were retrieved from our collective SDMS database. Variables evaluated included:demographics, Body Mass Index (BMI), AJCC stage, tumor location and Ca 19-9.A total of 185 pts had all data available pertaining to these variables. We further restricted the analysis to pts with intrahepatic CCA classified BMI as per CDC criteria normal (18.5-25kg/m2), overweight (25-29.9kg/m2) and obese (≥30 kg/m2), thus leaving a total of 152 pts. Continuous and categorical variables were compared across BMI groups using Chi-squared or Fisher’s exact test. Overall survival rates after diagnosis at 1, 2 and 3 years were estimated using Kaplan-Meier method. Results: Among 152 pts included in the study, 28% were normal weight, 40% were overweight and 32% were obese. The overall survival rate at 1, 2 and 3 years for normal weight pts with all stages combined was 54.1%, 35%, and 30.7%, respectively. The overall survival rate at 1, 2 and 3 years for overweight pts with all stages combined was 59.7 %, 32.6%, and 25.4%, respectively. The overall survival rate at 1, 2 and 3 years for obese pts with all stages combined was 63.9%, 37.6%, and 26.7%, respectively(p = 0.8766). Multivariate analysis demonstrated is no significant difference in overall survival for obese pts compared to normal or overweight pts.(Table to be shown) However it showed, gender and Ca19-9 were statistically significant predictors of overall survival, with males and pts with Ca19-9≥100 doing worse (HR1.65 (CI = 1.05, 2.61, p = 0.031) and HR 2.31 (CI = 1.49, 3.59, p = < 0.01), respectively). Conclusions: BMI did not make a significant impact on the overall survival, though there may be a trend toward worse OS for ptswith higher BMI. A larger, stage focused evaluation is warranted for further exploration of this trend.


2018 ◽  
Vol 43 (2) ◽  
pp. 128-135 ◽  
Author(s):  
CD Bergoli ◽  
LP Brondani ◽  
VF Wandscher ◽  
GKR Pereira ◽  
MS Cenci ◽  
...  

SUMMARY Objectives: The aim of this prospective randomized multicenter clinical trial was to evaluate the survival rate of glass fiber–reinforced posts cemented with self-adhesive or regular resin cements. Methods: The sample was comprised of 152 teeth randomized within two centers and in accordance with the adhesive strategies for RelyX U100/U200 (3M ESPE) or Single Bond and RelyX ARC (3M ESPE). The cementation procedures were standardized and performed by previously trained operators. The primary outcome evaluated was post debonding. A trained evaluator, one for each center, assessed all subjects at intervals of 12 months for up to 6 years. Statistical analysis was performed using the Kaplan-Meier method. Results: There was no statistically significant difference in survival rates between the two strategies assessed (p=0.991), with a 92.7% survival rate for the self-adhesive cement and 93.8% for the regular cement. Conclusion: Both the self-adhesive and the regular resin cements are good alternatives for glass fiber post cementation.


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