scholarly journals Constraining Roche-Lobe Overflow Models Using the Hot-Subdwarf Wide Binary Population

2017 ◽  
Vol 26 (1) ◽  
pp. 275-279
Author(s):  
Joris Vos ◽  
Maja Vučković

AbstractOne of the important issues regarding the final evolution of stars is the impact of binarity. A rich zoo of peculiar, evolved objects are born from the interaction between the loosely bound envelope of a giant, and the gravitational pull of a companion. However, binary interactions are not understood from first principles, and the theoretical models are subject to many assumptions. It is currently agreed upon that hot subdwarf stars can only be formed through binary interaction, either through common envelope ejection or stable Roche-lobe overflow (RLOF) near the tip of the red giant branch (RGB). These systems are therefore an ideal testing ground for binary interaction models. With our long term study of wide hot subdwarf (sdB) binaries we aim to improve our current understanding of stable RLOF on the RGB by comparing the results of binary population synthesis studies with the observed population. In this article we describe the current model and possible improvements, and which observables can be used to test different parts of the interaction model.

Heart ◽  
2019 ◽  
Vol 106 (4) ◽  
pp. 299-306
Author(s):  
Tsukasa Kamakura ◽  
Tetsuji Shinohara ◽  
Kenji Yodogawa ◽  
Nobuyuki Murakoshi ◽  
Hiroshi Morita ◽  
...  

ObjectiveLimited data are currently available regarding the long-term prognosis of patients with J-wave syndrome (JWS). The aim of this study was to investigate the long-term prognosis of patients with JWS and identify predictors of the recurrence of ventricular fibrillation (VF).MethodsThis was a multicentre retrospective study (seven Japanese hospitals) involving 134 patients with JWS (Brugada syndrome (BrS): 85; early repolarisation syndrome (ERS): 49) treated with an implantable cardioverter defibrillator. All patients had a history of VF. All patients with ERS underwent drug provocation testing with standard and high intercostal ECG recordings to rule out BrS. The impact of global J waves (type 1 ECG or anterior J waves and inferolateral J waves in two or more leads) on the prognosis was evaluated.ResultsDuring the 91±66 months of the follow-up period, 52 (39%) patients (BrS: 37; ERS: 15) experienced recurrence of VF. Patients with BrS and ERS with global J waves showed a significantly higher incidence of VF recurrence than those without (BrS: log-rank, p=0.014; ERS: log-rank, p=0.0009). The presence of global J waves was a predictor of VF recurrence in patients with JWS (HR: 2.16, 95% CI 1.21 to 3.91, p=0.0095), while previously reported high-risk electrocardiographic parameters (high-amplitude J waves ≥0.2 mV and J waves associated with a horizontal or descending ST segment) were not predictive of VF recurrence.ConclusionsThis multicentre long-term study showed that the presence of global J waves was associated with a higher incidence of VF recurrence in patients with JWS.


1997 ◽  
Vol 3 (3) ◽  
pp. 206 ◽  
Author(s):  
G. Barry Baker ◽  
E. Belinda Dettmann ◽  
Stephen J. Wilson

Survival rate, population size, recruitment and probability of capture, derived from a long-term study of 20 passerine species in wet sclerophyll forest near Canberra, were used to measure the impact of a high intensity wildfire which burnt 70% of the study area. The wildfire significantly affected the population size of 13 species for a period of up to six years following the fire. Survival and recruitment were the least sensitive measures of impact and indicated a significant response to fire for only 2 of 10 species. We detected measurable effects of the fire for 17 of the 20 species studied. Many of these species had returned to prefire levels within three years, but for nine species the effects were still apparent six years later. Mark-recapture methodology provides an effective way of measuring the impact of fire regimes in forest environments. Long-term monitoring programmes should be established in fire-prone forest environments to contribute toward our understanding of fire, and its effect on avian populations. Such programmes have resource implications and researchers are urged to encourage the participation of the amateur bird banding community to contribute to such projects.


Parasitology ◽  
2015 ◽  
Vol 142 (8) ◽  
pp. 1033-1043 ◽  
Author(s):  
M. ZYLBERBERG ◽  
E. P. DERRYBERRY ◽  
C. W. BREUNER ◽  
E. A. MACDOUGALL-SHACKLETON ◽  
J. M. CORNELIUS ◽  
...  

SUMMARYThe impact of haematozoan infection on host fitness has received substantial attention since Hamilton and Zuk posited that parasites are important drivers of sexual selection. However, short-term studies testing the assumption that these parasites consistently reduce host fitness in the wild have produced contradictory results. To address this complex issue, we conducted a long-term study examining the relationship between naturally occurring infection withHaemoproteusandPlasmodium, and lifetime reproductive success and survival of Mountain White-crowned Sparrows. Specifically, we tested the hypothesis that birds infected with haematozoan parasites have reduced survival (as determined by overwinter return rates) and reproductive success. Contrary to expectation, there was no relationship betweenHaemoproteusandPlasmodiuminfection and reproduction or survival in males, nor was there a relationship betweenPlasmodiuminfection and reproduction in females. Interestingly,Haemoproteus-infected females had significantly higher overwinter return rates and these females fledged more than twice as many chicks during their lifetimes as did uninfected females. We discuss the impact of parasitic infections on host fitness in light of these findings and suggest that, in the case of less virulent pathogens, investment in excessive immune defence may decrease lifetime reproduction.


2015 ◽  
Vol 84 ◽  
pp. 8-17 ◽  
Author(s):  
N. Sayi-Ucar ◽  
M. Sarioglu ◽  
G. Insel ◽  
E.U. Cokgor ◽  
D. Orhon ◽  
...  

2009 ◽  
pp. 702-724
Author(s):  
Colleen Cunningham ◽  
Il-Yeol Song ◽  
Peter P. Chen

CRM is a strategy that integrates concepts of knowledge management, data mining, and data warehousing in order to support an organization’s decision-making process to retain long-term and profitable relationships with its customers. This research is part of a long-term study to examine systematically CRM factors that affect design decisions for CRM data warehouses in order to build a taxonomy of CRM analyses and to determine the impact of those analyses on CRM data warehousing design decisions. This article presents the design implications that CRM poses to data warehousing and then proposes a robust multidimensional starter model that supports CRM analyses. Additional research contributions include the introduction of two new measures, percent success ratio and CRM suitability ratio by which CRM models can be evaluated, the identification of and classification of CRM queries, and a preliminary heuristic for designing data warehouses to support CRM analyses.


Hepatology ◽  
2020 ◽  
Vol 72 (4) ◽  
pp. 1177-1190 ◽  
Author(s):  
Habiba Kamal ◽  
Gabriel Westman ◽  
Karolin Falconer ◽  
Ann‐Sofi Duberg ◽  
Ola Weiland ◽  
...  

2018 ◽  
Vol 66 ◽  
pp. 02006
Author(s):  
Adam Kanciruk

The article discusses five year long measurements of strains of a concrete floor of a hangar. That hangar, originally meant for servicing light military aircraft, was rebuilt with a view to making it fit for servicing larger and heavier passenger planes. As part of that redevelopment, a new floor - reinforced concrete slab, capable of withstanding the weight of the planes - was constructed. In the areas of the floor where the greatest loads occur, ie. in the areas of the concrete slab on which the wheels of the three undercarriage legs rest, three strain rosettes were installed so that the slab strains could be measured. The rosettes were connected to two meters - dataloggers. The latter were programmed in such a way as to register the measured strains and additionally temperatures many times during every 24 hours. The monitoring process, conducted in such an automatic way, demonstrated the occurrence of strains resulting from service load, aging of the reinforced concrete, as well as changes in its temperature.


2011 ◽  
pp. 731-752
Author(s):  
Colleen Cunningham ◽  
Il-Yeol Song ◽  
Peter P. Chen

CRM is a strategy that integrates concepts of knowledge management, data mining, and data warehousing in order to support an organization’s decision-making process to retain long-term and profitable relationships with its customers. This research is part of a long-term study to examine systematically CRM factors that affect design decisions for CRM data warehouses in order to build a taxonomy of CRM analyses and to determine the impact of those analyses on CRM data warehousing design decisions. This article presents the design implications that CRM poses to data warehousing and then proposes a robust multidimensional starter model that supports CRM analyses. Additional research contributions include the introduction of two new measures, percent success ratio and CRM suitability ratio by which CRM models can be evaluated, the identification of and classification of CRM queries, and a preliminary heuristic for designing data warehouses to support CRM analyses.


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