scholarly journals Does Risk of Nest Failure or Adult Predation Influence Hatching Patterns of the Green-Rumped Parrotlet?

The Condor ◽  
2001 ◽  
Vol 103 (1) ◽  
pp. 85-97 ◽  
Author(s):  
Scott H. Stoleson ◽  
Steven R. Beissinger
Keyword(s):  
High Risk ◽  
Field Data ◽  
Survival Rates ◽  
Tropical Species ◽  
Failure Model ◽  
Nest Failure ◽  
Egg Incubation ◽  
Forpus Passerinus ◽  
Adult Females ◽  
Model Predictions

Abstract Parent birds may adjust the onset of incubation to minimize periods of high risk of nest failure due to predation (the Nest Failure Hypothesis) or of mortality to adult birds (the Adult Predation Hypothesis). We examine temporal patterns of risk of nest failure and predation on adult females in a population of Green-rumped Parrotlets (Forpus passerinus) to determine whether those patterns explain observed patterns of incubation. Over one-third of nests (38.6%) failed completely, and an additional 2.2% failed after fledging one or more young. Most nests failed due to predation and infanticide. Because parrotlets begin incubation on the first egg, we examined a range of hypothetical failure rates for the period prior to the onset of incubation. Daily survival probabilities for nests were higher during the nestling stage than during incubation or fledging. Survival of adult females varied little through the nesting cycle, but was highest while attending nestlings. Model predictions were highly dependent on assumptions made about survival rates during the pre-incubation period. When empirically based values were used for this period, maximum productivity was achieved with first-egg incubation, consistent with observed patterns. Models were most sensitive to those parameters most difficult to estimate. This study represents the first test of the Nest Failure model with a nonpasserine or tropical species, and the first assessment of the Adult Predation model using field data.

Status of the Hawaiian monk seal (Monachus schauinslandi) population

1995 ◽  
Vol 73 (6) ◽  
pp. 1185-1190 ◽  
Author(s):  
W. G. Gilmartin ◽  
L. L. Eberhardt
Keyword(s):  
Complex System ◽  
Sex Ratios ◽  
Current Trend ◽  
Survival Rates ◽  
Hawaiian Monk Seal ◽  
Monachus Schauinslandi ◽  
Young Females ◽  
Adult Females ◽  
Unknown Factor ◽  
Adult Sex Ratio

Restoration of the Hawaiian monk seal (Monachus schauinslandi) population to its former abundance poses a number of problems in managing a complex system. Sharp differences in history and current trend exist among the six major pupping sites. A severely unbalanced adult sex ratio has resulted in deaths from "mobbing" of estrus females at two sites. Some unknown factor apparently severely reduced the numbers of females at three of the sites and thus produced the observed excess of males. Sex ratios subsequently decreased, but losses of adult females continue at two sites. A simple model indicates that sex ratios at the two sites where mobbing is a problem would require more than 10 years to approach an equilibrium value. Data on trends from counts are compared with estimates from reproduction and survival rates and agree closely except at one site (Kure Atoll), where introductions of young females have been made.

scholarly journals Predictors for the Immediate and Long-Term Outcome of Avascular Surgical Procedure

2009 ◽  
Vol 98 (3) ◽  
pp. 164-168 ◽  
Author(s):  
J. Virkkunen ◽  
M. Venermo ◽  
J. Saarinen ◽  
J. Salenius
Keyword(s):  
Risk Factors ◽  
Risk Factor ◽  
High Risk ◽  
Predictive Value ◽  
Surgical Procedure ◽  
Operative Mortality ◽  
Survival Rates ◽  
Term Outcome ◽  
Long Term Outcome

Background and Aims: The ability to predict post-operative mortality reliably will be of assistance in making decisions concerning the treatment of an individual patient. The aim of this study was to test the GAS score as a predictor of post-operative mortality in vascular surgical patients. Material and Methods: A total of 157 consecutive patients who underwent an elective vascular surgical procedure were included in the study. The Cox proportional hazards model was used in analyzing the importance of various preoperative risk factors for the postoperative outcome. ASA and GAS were tested in predicting the short and long-term outcome. On the basis of the GAS cut-off value 77, patients were selected into low-risk (GAS low: GAS < 77) and high-risk (GAS high: GAS > = 77) groups, and the examined risk factors were analyzed to determine which of them had predictive value for the prognosis. Results: None of the patients in the GAS low group died, and mortality in the GAS high group was 4.8% (p = 0.03) at 30 days' follow-up. The 12-month survival rates were 98.6% and 78.6% (p = 0.0001), respectively, with the respective 5-year survival rates of 76.7% and 44.0% (p = 0.0001). The only independent risk factor for 30-day mortality was the renal risk factor (OR 20.2). The combination of all three GAS variables(chronic renal failure, cardiac disease and cerebrovascular disease), excluding age, was associated with a 100% two-year mortality. Conclusions: Mortality is low for patients with GAS<77. For the high-risk patients (GAS> = 77), due to its low predictive value for death, GAS yields limited value in clinical practice. In cases of patients with all three risk factors (renal, cardiac and cerebrovascular), vascular surgery should be considered very carefully.

scholarly journals Technical Note: Approximate Bayesian parameterization of a complex tropical forest model

2013 ◽  
Vol 10 (8) ◽  
pp. 13097-13128 ◽  
Author(s):  
F. Hartig ◽  
C. Dislich ◽  
T. Wiegand ◽  
A. Huth
Keyword(s):  
Parameter Estimation ◽  
Tropical Forest ◽  
Field Data ◽  
Complex Data ◽  
Forest Model ◽  
Likelihood Approximation ◽  
Simulation Based ◽  
Model Predictions ◽  
Approximate Bayesian ◽  
Process Based Models

Abstract. Inverse parameter estimation of process-based models is a long-standing problem in ecology and evolution. A key problem of inverse parameter estimation is to define a metric that quantifies how well model predictions fit to the data. Such a metric can be expressed by general cost or objective functions, but statistical inversion approaches are based on a particular metric, the probability of observing the data given the model, known as the likelihood. Deriving likelihoods for dynamic models requires making assumptions about the probability for observations to deviate from mean model predictions. For technical reasons, these assumptions are usually derived without explicit consideration of the processes in the simulation. Only in recent years have new methods become available that allow generating likelihoods directly from stochastic simulations. Previous applications of these approximate Bayesian methods have concentrated on relatively simple models. Here, we report on the application of a simulation-based likelihood approximation for FORMIND, a parameter-rich individual-based model of tropical forest dynamics. We show that approximate Bayesian inference, based on a parametric likelihood approximation placed in a conventional MCMC, performs well in retrieving known parameter values from virtual field data generated by the forest model. We analyze the results of the parameter estimation, examine the sensitivity towards the choice and aggregation of model outputs and observed data (summary statistics), and show results from using this method to fit the FORMIND model to field data from an Ecuadorian tropical forest. Finally, we discuss differences of this approach to Approximate Bayesian Computing (ABC), another commonly used method to generate simulation-based likelihood approximations. Our results demonstrate that simulation-based inference, which offers considerable conceptual advantages over more traditional methods for inverse parameter estimation, can successfully be applied to process-based models of high complexity. The methodology is particularly suited to heterogeneous and complex data structures and can easily be adjusted to other model types, including most stochastic population and individual-based models. Our study therefore provides a blueprint for a fairly general approach to parameter estimation of stochastic process-based models in ecology and evolution.

scholarly journals A meta-analysis of global avian survival across species and latitude

2019 ◽  
Author(s):  
Micah N. Scholer ◽  
Matt Strimas-Mackey ◽  
Jill E. Jankowski
Keyword(s):  
Latitudinal Gradient ◽  
Meta Analysis ◽  
Survival Rates ◽  
Global Scale ◽  
Geographic Region ◽  
Passerine Birds ◽  
Tropical Birds ◽  
Model Predictions ◽  
Improved Model ◽  
Northern And Southern Hemispheres

AbstractTropical birds are purported to be longer lived than temperate species of similar size, but it has not been shown whether avian survival rates covary with a latitudinal gradient worldwide. Here, we perform a global-scale meta-analysis to investigate the extent of the latitudinal survival gradient. We modeled survival as a function of latitude for the separate northern and southern hemispheres, and considered phylogenetic relationships and extrinsic (climate) and intrinsic (life history) predictors hypothesized to moderate these effects. Using a database of 1,004 estimates from 246 studies of avian survival, we demonstrate that in general a latitudinal survival gradient exists in the northern hemisphere, is dampened or absent for southern hemisphere species, and that survival rates of passerine birds largely account for these trends. We found no indication that the extrinsic climate factors were better predictors of survival than latitude alone, but including species’ intrinsic traits improved model predictions. Notably, species with smaller clutch size and larger body mass showed higher survival. Our results illustrate that while some tropical birds may be longer lived than their temperate counterparts, the shape of the latitude-survival gradient differs by geographic region and is strongly influenced by species’ intrinsic traits.

Young Adult Females’ Perceptions of High-Risk Social Media Behaviors: A Focus-Group Approach

2014 ◽  
Vol 31 (3) ◽  
pp. 133-144
Author(s):  
Amber L. Virden ◽  
Angelia Trujillo ◽  
Elizabeth Predeger
Keyword(s):  
Social Media ◽  
Young Adult ◽  
High Risk ◽  
Focus Group ◽  
Group Approach ◽  
Adult Females

scholarly journals The preoperative prognostic value of the radiomics nomogram based on CT combined with machine learning in patients with intrahepatic cholangiocarcinoma

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Youyin Tang ◽  
Tao Zhang ◽  
Xianghong Zhou ◽  
Yunuo Zhao ◽  
Hanyue Xu ◽  
...  
Keyword(s):  
Overall Survival ◽  
High Risk ◽  
Intrahepatic Cholangiocarcinoma ◽  
Prognostic Value ◽  
Survival Rates ◽  
Low Risk ◽  
Liver Carcinoma ◽  
Incidence And Mortality ◽  
Significant Difference ◽  
Prognostic Prediction

Abstract Background Intrahepatic cholangiocarcinoma is an aggressive liver carcinoma with increasing incidence and mortality. A good auxiliary prognostic prediction tool is desperately needed for the development of treatment strategies. The purpose of this study was to explore the prognostic value of the radiomics nomogram based on enhanced CT in intrahepatic cholangiocarcinoma. Methods In this retrospective study, 101 patients with pathological confirmation of intrahepatic cholangiocarcinoma were recruited. A radiomics nomogram was developed by radiomics score and independent clinical risk factors selecting from multivariate Cox regression. All patients were stratified as high risk and low risk by a nomogram. Model performance and clinical usefulness were assessed by calibration curve, ROC curve, and survival curve. Results A total of 101patients (mean age, 58.2 years old; range 36–79 years old) were included in the study. The 1-year, 3-year, and 5-year overall survival rates were 49.5%, 26.6%, and 14.4%, respectively, with a median survival time of 12.2 months in the whole set. The least absolute shrinkage and selection operator (LASSO) method selected 3 features. Multivariate Cox analysis found three independent prognostic factors. The radiomics nomogram showed a significant prognosis value with overall survival. There was a significant difference in the 1-year and 3-year survival rates of stratified high-risk and low-risk patients in the whole set (30.4% vs. 56.4% and 13.0% vs. 30.6%, respectively, p = 0.018). Conclusions This radiomics nomogram has potential application value in the preoperative prognostic prediction of intrahepatic cholangiocarcinoma and may facilitate in clinical decision-making.

A New Prognostic Disease Specific Model To Predict Survival after Intensive Antileukemic Treatment for Young Patients with Poor-Risk MDS and AML: Results of the CRIANT and AML-10 Studies Conducted by the EORTC/GIMEMA/SAKK/HOVON/EBMT Groups.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2020-2020
Author(s):  
M. Oosterveld ◽  
S. Suciu ◽  
P. Muus ◽  
M. Delforge ◽  
A. Belhabri ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
High Risk ◽  
Prognostic Value ◽  
De Novo ◽  
Survival Rates ◽  
White Blood Count ◽  
Poor Risk ◽  
Prognostic Importance ◽  
De Novo Aml ◽  
Disease Specific

Abstract The use of intensive antileukemic treatment is less widely accepted in high-risk MDS pts compared to de novo AML, due to the reported inferior results. It is questionable whether the poorer outcome reflects an intrinsic property of the involved stem cell or a higher frequency of poor prognostic factors. The purpose of this analysis is to identify disease-specific prognostic factors for outcome of young (aged <56 years) MDS and AML pts. This analysis combines the data of 591 pts in the AML-10 study and 203 pts with high-risk MDS or secondary AML (sAML) in the CRIANT study. Both groups received identical remission-induction therapy (idarubicin, cytarabine and etoposide), followed by one consolidation course with intermediate dose of cytarabine and idarubicin (IDIA). In both studies post-consolidation therapy consisted of alloSCT if an HLA-identical sibling donor was available. The remaining pts received autoSCT (ASCT) in AML-10 or were randomized between ASCT and a 2nd consolidation course in CRIANT. The CR rate was 68% (AML-10) vs. 59% (CRIANT) (p=0.02). The 4-year survival rates were 35% vs. 33% (p=0.80). DFS at 4 years was 43% (AML-10) vs. 35% (CRIANT) (p=0.18). For overall survival (OS) in both studies, study was not of importance (HR=1.09, p=0.45), but the following variables showed independent prognostic value: cytogenetic risk group (the HR for poor vs intermediate risk was 1.68, 95% CI 1.24–2.27, p=0.0008), white blood count (WBC) ≥ 100 x 109/l (HR=2.02, 95% CI 1.53–2.68, p<0.0001), age 46–55 yrs (HR=1.39, 95% CI 1.16–1.67, p=0.0004) and performance status (PS) (HR=1.32, 95% CI 1.17–1.49, p <0.0001). For DFS, the following factors were of an independent prognostic importance: cytogenetics (p<0.0001), age 46–55 (HR=1.23, p=0.05), WBC >100 (HR=1.67, p=0.02) and donor availability (HR=0.77, p=0.04). Some variables were of prognostic value for OS in only one of the studies: in the CRIANT study number of cytopenias (3 vs 0–2) and AHD >6 months appeared of prognostic importance for OS, wherease FAB subtype M2/M4 and cytogenetics inv(16)/t(8;21) were prognostic in AML-10. Therefore a specific prognostic score for OS was established for each study, AML-10 (based on cytogenetics, PS, FAB, WBC and age) and CRIANT (based on cytogenetics, nr of cytopenias, age, AHD and WBC). The AML-10 study distinguished 5 groups with an estimated 4-year survival rate of 69%, 40%, 45%, 26% and 17%, resp. The prognostic value of this score has been validated on patients treated in the AML-10 study with mitoxantrone instead of idarubicin: the 4-year survival were 76%, 46%, 41%, 33% and 18%, resp. The CRIANT study distinguished 5 groups with a 4-year survival rates of 72%, 44%, 39%, 12% and 0%, resp. In conclusion: the prognostic scores identify a group of 26% AML and 42% MDS pts, with a 4-year survival less than 20%. Apparently current treatment modalities are unsatisfactory for these poor-risk pts and novel treatment strategies should be offered to these pts in the context of clinical trials. Our finding that different variables are of prognostic importance in MDS/sAML and de novo AML pts supports the hypothesis that these are intrinsically different disorders. The CRIANT-derived score is a valuable alternative for the IPSS in intensively treated high-risk MDS pts.

A Retrospective Study to Evaluate the Survival Rates in R-CHOP Chemotherapy Followed by Autologous Stem Cell Transplantation for the Treatment of Diffuse Large B Cell Lymphoma

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4517-4517
Author(s):  
Mark H. Lee ◽  
Sung-Yong Kim ◽  
Inho Kim ◽  
Seonyang Park ◽  
Yeo-Kyeoung Kim ◽  
...  
Keyword(s):  
Stem Cell ◽  
High Risk ◽  
Stem Cell Transplantation ◽  
B Cell ◽  
Cell Lymphoma ◽  
Survival Rates ◽  
B Cell Lymphoma ◽  
Bulky Disease ◽  
Large B Cell Lymphoma ◽  
Large B Cell

Abstract Abstract 4517 Prognosis in diffuse large B cell lymphoma (DLBCL) is highly associated with the International Prognostic Index (IPI) score, which was proposed to assign prognosis to patients with aggressive non-Hodgkin lymphoma undergoing treatment with doxorubicin-containing chemotherapy. The addition of rituximab to CHOP or CHOP-like regimens has resulted in significant improvements in the overall survival (OS) rate of CD20 positive DLBCL. In addition, the original IPI scoring system has been validated even in patients receiving rituximab-based chemotherapy. However, OS and progression-free survival (PFS) in patients with high-intermediate or high IPI DLBCL were not satisfactory, and the upfront autologous stem cell transplantation (ASCT) was reported to improve the survival rates in these patients subset. Therefore, we retrospectively evaluated the survival rates in patients with DLBCL with CD20+, who were treated with R-CHOP followed by ASCT. We analyzed 40 DLBCL patients who underwent an ASCT, reported to the Korean Blood and Marrow Transplant Registry between 2005 and 2011 by 12 centers. Patients characteristics at diagnosis: 60% male, 5% stage II with bulky disease, 95% stage III or IV, 42.5% bone marrow involvement, 65% high-intermediate or high risk by IPI score. Patients characteristics at ASCT: median age 47 years (range, 23–66) and 82.5% of patients received ≥6 cycles of R-CHOP. Response to R-CHOP: 62.5% CR and 37.5% PR. 17.5% of patients received involved field radiotherapy prior to ASCT for bulky disease or residual lymphoma. Disease status at ASCT: 72.5% CR and 27.5% PR. Median time from diagnosis to ASCT was 7.85 months (range, 4.4–16.1). Median follow-up period from diagnosis was 36.2 months (range, 6.3–84.8). 2-year estimates of PFS, OS and relapse from diagnosis were 73.8%, 86.4% and 24.3%, respectively. 5-year estimates of PFS, OS and relapse were 70.8%, 68.3% and 27.4%, respectively. 3-year estimates of PFS and OS according to IPI score were not significantly different among 4 risk groups (P=0.890 and P=0.855, respectively). The upfront ASCT following R-CHOP induction therapy may improve survival for patients with advanced high risk DLBCL. Prospective evaluation of the treatment outcome of R-CHOP followed by ASCT is needed for high risk DLBCL on a large scale. Disclosures: No relevant conflicts of interest to declare.

High-Dose Chemotherapy and Autologous Stem Cell Transplantation In Patients With High-Risk Neuroblastoma : Results Of Turkish Pediatric Oncology Group- Neuroblastoma 2003 (TPOG-NBL 2003) Protocol

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3411-3411 ◽  
Author(s):  
Serap Aksoylar ◽  
Ali Varan ◽  
Canan Vergin ◽  
Volkan Hazar ◽  
Ferhan Akici ◽  
...  
Keyword(s):  
Stem Cell ◽  
High Risk ◽  
Induction Chemotherapy ◽  
Conflicts Of Interest ◽  
Survival Rates ◽  
High Dose Chemotherapy ◽  
High Dose ◽  
Intention To Treat ◽  
Stem Cell Rescue ◽  
Chemotherapy Patients

Abstract Introduction TPOG-NBL 2003 national protocol was designed to improve treatment results of the high risk patients by adjunction of stem cell rescue with intensive multimodal therapy. Material and Methods High risk stratification was made according to COG criteria. Just before the third cycle of chemotherapy, patients without progression were allocated into two treatment groups non-randomly by physicians’ and/or parent’s choices guided to the center’s facility, toxicity and social-economical facility to attain the megatherapy. After an induction of 6 chemotherapy cycles, the protocol was divided into two arms which were designed to continue the intensive conventional chemotherapy (CCT), or initiate myeloablative therapy with autologous stem-cell rescue (ASCR). All patients were also given 13-cis-retinoic acid as maintenance therapy. Results Fifty-six percent (272 patients) of all neuroblastoma patients was evaluated as high risk. Response rate to induction chemotherapy was 81% (CR/VGPR: 32%, PR: 49%) in patients at the end of induction chemotherapy. Overall EFS and OS at 3-years were 36% and 45%, respectively. Intention-to-treat analysis documented post-induction (after the six cycles of induction chemotherapy) EFS of 46% in CCT arm (137 patients) and 37% in ASCR group (55 patients) (p= 0.037); whereas, OS was 59% and 43%, respectively (p=0.052). Thirty-one patients (11%) died of treatment-related complications. Conclusion Survival rates of high-risk neuroblastoma have improved over the last decade in Turkey. The main problems when managing these patients were an effective local control, early progression and death. Megatherapy has not augmented the therapeutic end point in our country’s circumstances. However; the better the supportive care and the higher the patients’ compliance is attained, the higher the survival rates might be obtained in Turkish neuroblastoma patients. Disclosures: No relevant conflicts of interest to declare.

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