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.

Effect of Temperature and Size on Development, Mortality, and Survival Rates of the Pelagic Early Life History Stages of Marine Fish

1991 ◽  
Vol 48 (3) ◽  
pp. 503-518 ◽  
Author(s):  
Pierre Pepin
Keyword(s):  
Early Life ◽  
Survival Rates ◽  
Early Life History ◽  
Mortality Rates ◽  
Yolk Sac ◽  
Vital Rates ◽  
Daily Mortality ◽  
Cumulative Mortality ◽  
Life History Stages ◽  
Size Dependent

This paper presents a comprehensive summary of development, mortality, and survival rates of fish eggs, yolk-sac larvae, and postlavae in relation to temperature and size. The general temperature- and, where applicable, size-dependent models explained 30–81% of the variance in vital rates. Daily development and mortality rates generally increased with increasing temperature. Temperature had an equal but opposite effect on stage-specific cumulative mortality rates of eggs and yolk-sac larvae. Stage-specific (length-dependent) cumulative mortality rates of postlarval fish were independent of temperature due to equal effects of temperature on daily growth and daily mortality rates. Size had no significant effect on daily or cumulative mortality rates of egg and yolk-sac stages. Daily mortality rates of postlarval fish were significantly influenced by mean size (i.e. length). The compensation of temperature effects between stages and/or vital rates may reduce the impact of environmental uncertainty on survival rates. It is suggested that the general temperature- and/or size-dependent relationships described in this study can serve as basic frameworks to assess whether there are significant effects resulting from species/stock-specific characteristics or environmental factors on the vital rates of the early life history stages of fish.

scholarly journals Carotid Endarterectomy In Octogenarians: Is It Worth The Effort?

Stroke ◽  
2001 ◽  
Vol 32 (suppl_1) ◽  
pp. 333-333
Author(s):  
Enrico Ascher ◽  
Prasad Gade ◽  
Anil Hingorani ◽  
Yilmaz Gunduz
Keyword(s):  
Carotid Endarterectomy ◽  
Survival Rates ◽  
The Elderly ◽  
Chi Square ◽  
Old Patients ◽  
Limited Life ◽  
History Of ◽  
Similar Survival ◽  
Two Populations

96 Objective. Safety, effectiveness and cost issues of carotid endarterectomy (CEA) in the elderly patient have been debated because of limited life expectancy and presumably increased complications. We compared characteristics of two populations who underwent CEA: 80 or older (older group) and 65–79 year old patients (younger group). Methods. Medical and financial data were obtained by retrospective review of hospital charts and billing records. Recent follow-up was accomplished by telephone interview. Life-table and Chi-square tests were used for statistical analysis. We analyzed 109 CEAs performed in 101 older patients from 2/1/90 to 8/30/97 and 125 CEAs performed in 121 younger patients. Results. Comparing the older with younger groups, there were no differences in gender (50% male vs 59%), incidence of preop CVA (22% vs 17%) history of TIA (23% vs 25%), amaurosis fugax (6% vs 8%), hypertension (62% vs 60%), combined perioperative death and stroke rate (1.8% vs 1.7%) or other complications (11% vs 10%). Significant differences (p<0.05) were noted between older and younger groups in incidence of diabetes (17% in the older group vs 30%) , smoking (39% vs57%) and heart disease (48% vs 28%). Length of stay (2.8 in older group vs 3.0 days) or hospital cost including readmission for treatment of complications ($9,400 in older vs $7,842) were similar. Survival rates were not significantly different at the end of three years of follow up. Conclusions. Carotid endarterectomy can be performed in the elderly as safely and cost effectively as in the younger population.

scholarly journals Sensitive males: inbreeding depression in an endangered bird

2010 ◽  
Vol 277 (1700) ◽  
pp. 3677-3684 ◽  
Author(s):  
Patricia Brekke ◽  
Peter M. Bennett ◽  
Jinliang Wang ◽  
Nathalie Pettorelli ◽  
John G. Ewen
Keyword(s):  
Inbreeding Depression ◽  
Threatened Species ◽  
Genetic Load ◽  
Early Life History ◽  
Molecular Sexing ◽  
Life History Stages ◽  
Inbreeding Coefficients ◽  
Nestling Development ◽  
Autosomal Microsatellite Loci

Attempts to conserve threatened species by establishing new populations via reintroduction are controversial. Theory predicts that genetic bottlenecks result in increased mating between relatives and inbreeding depression. However, few studies of wild sourced reintroductions have carefully examined these genetic consequences. Our study assesses inbreeding and inbreeding depression in a free-living reintroduced population of an endangered New Zealand bird, the hihi ( Notiomystis cincta ). Using molecular sexing and marker-based inbreeding coefficients estimated from 19 autosomal microsatellite loci, we show that (i) inbreeding depresses offspring survival, (ii) male embryos are more inbred on average than female embryos, (iii) the effect of inbreeding depression is male-biased and (iv) this population has a substantial genetic load. Male susceptibility to inbreeding during embryo and nestling development may be due to size dimorphism, resulting in faster growth rates and more stressful development for male embryos and nestlings compared with females. This work highlights the effects of inbreeding at early life-history stages and the repercussions for the long-term population viability of threatened species.

Grenadiers of the World Oceans: Biology, Stock Assessment, and Fisheries

2008 ◽  
Keyword(s):  
Life History ◽  
Early Life ◽  
Stock Assessment ◽  
Early Life History ◽  
Wide Distribution ◽  
Life History Stages ◽  
The North ◽  
The World ◽  
Long Passive ◽  
The North Atlantic

<em>Abstract</em>.—Surveys undertaken in 2003 and 2005 have increased our knowledge of the distribution of roundnose grenadier <em>Coryphaenoides rupestris </em>in the North Atlantic. The data suggest a wide distribution of young grenadier in the high seas and support previous assumptions about long passive migrations of this species at early life-history stages.

Survival of Arteriovenous Fistula for Dialysis at Different Centers in the North of England

2007 ◽  
Vol 8 (4) ◽  
pp. 231-234 ◽  
Author(s):  
P.C. Shrestha ◽  
J. Asher ◽  
S.M. Shrestha ◽  
S. Jenner ◽  
C. Wilson ◽  
...  
Keyword(s):  
Survival Rates ◽  
Current Mode ◽  
Hemodialysis Patients ◽  
Arteriovenous Fistulae ◽  
Surgical Practice ◽  
The North ◽  
Surgical Access ◽  
Kaplan Meier ◽  
History Of ◽  
Access Surgery

Background Renal failure patients rely on their vascular access for hemodialysis. Surgery for construction of arteriovenous fistulae is provided by a range of specialists. The aim of this review was to assess the survival of arteriovenous fistulae for hemodialysis patients in different centers of Northern England. Methods Data was collected on 473 hemodialysis patients in the North of England. Risk factors for failure were determined for each patient (age, sex, diabetes), together with their current mode of dialysis and history of surgical access procedures. This was expressed against their duration of dialysis. The dialysis units were then compared for fistula survival using the Kaplan Meier method. Results 68.3% (323) patients were dialysed through via arteriovenous fistulae and 31.7% (150) via neck line. Overall fistula survival rates were 85.1% at 1 year, 82.5% at 2 years and 72.7% at 3 years. The best 1 year survival was 91.6% and worst 76.1%. These were 74.4% and 53.1% at 5 years and 74.4% and 29.5% at 10 years; these differences were highly statistically significant (p=0.0033). Conclusion Though graft survival is affected by many things, surgical training in access surgery is not mandatory and a review of surgical practice is urgently needed.

Comparative review of Pacific salmon survival rates

1995 ◽  
Vol 52 (6) ◽  
pp. 1327-1338 ◽  
Author(s):  
Michael J. Bradford
Keyword(s):  
Life History ◽  
Survival Data ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Survival Rates ◽  
Adult Survival ◽  
Life History Stages ◽  
Comparative Review ◽  
History Of ◽  
The Mean

I collated estimates of survival from the literature for naturally reproducing populations of the five major commercially harvested species of Pacific salmon (Oncorhynchus spp.) and compared the mean and variability of survival across species and life-history stages. The conclusion that survival rates can be described with a lognormal distribution was extended to include both the marine and freshwater stages. Average egg–fry survival of pink (O. gorbuscha), chum (O. keta), and sockeye (O. nerka) salmon was similar (average 7%) but was significantly lower than that of coho salmon (O. kisutch, 19%). The egg–smolt survival of chinook (O. tshawytscha) was much higher than coho or sockeye that also rear in freshwater for similar periods (7 compared with 1–2%). No direct estimates exist for the marine survival rate of naturally spawning chinook stocks; however, from fecundity and freshwater survival data a species average of 1–2% was derived. Across all species freshwater contributes slightly more to total variation in egg–adult survival than does the ocean, and the schedule of mortality during the egg–adult interval depends on the natural history of each species.

scholarly journals Optimized Live Feed Regime Significantly Improves Growth Performance and Survival Rate for Early Life History Stages of Pangasius Catfish (Pangasianodon hypophthalmus)

Fishes ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 20
Author(s):  
Ngoc-Ut Vu ◽  
Truong-Giang Huynh
Keyword(s):  
Life History ◽  
Survival Rate ◽  
Early Life ◽  
Survival Rates ◽  
Early Life History ◽  
Growth And Survival ◽  
Pangasianodon Hypophthalmus ◽  
Life History Stages ◽  
The Third ◽  
Live Feed

This study aimed to determine the optimal live feed regime (i.e., initial feeding moment, density, and frequency) for maximum growth and survival of pangasius catfish (Pangasianodon hypophthalmus) early life history stages. The first experiment assessed the optimal initial feeding moment (30, 36, 42, and 48 h post hatching, hph). The second experiment assessed feeding density (3, 5, 8 and 11 individuals per mL, ind/mL) at the optimal initial feeding moment (30 hph) which was the best result from the first experiment. The third experiment assessed optimal feeding frequency (1, 2, 4, and 6 times per day) at the optimal initial feeding moment (30 hph) and density (8 ind/mL) which was drawn upon from the second experiment. All experiments were conducted in 20 L containers containing 20 hph P. hypophthalmus larvae at a density of 10 ind/L and fed rotifers (Brachionus angularis) for 3 days and then water fleas (Moina macrocopa) for 7 days. The first experiment demonstrated that larvae initially fed at 30 hph exhibited a significantly higher survival rate (24%) than larvae initially fed at 36, 42, and 48 hph (19%, 16%, and 16%), respectively. The second experiment demonstrated that larvae fed at 8 and 11 ind/mL densities exhibited significantly higher survival rates (32% and 32%) than larvae fed at 3 and 5 ind/mL densities (13% and 23%), respectively. The third experiment demonstrated that the highest survival rate (66%) was obtained when larvae were fed 6 times per day. These results provide valuable insights regarding the optimal live feed regime for better growth and survival of P. hypophthalmus larvae, which are commercially important and numerously cultured throughout the Mekong Delta region.

Ras al Khaimah: further archaeological discoveries

Antiquity ◽  
1976 ◽  
Vol 50 (200) ◽  
pp. 216-222
Author(s):  
Beatrice De Cardi
Keyword(s):  
United Arab Emirates ◽  
The State ◽  
Focused Attention ◽  
North East ◽  
The North ◽  
History Of ◽  
The City

Ras a1 Khaimah is the most northerly of the seven states comprising the United Arab Emirates and its Ruler, H. H. Sheikh Saqr bin Mohammad al-Qasimi, is keenly interested in the history of the state and its people. Survey carried out there jointly with Dr D. B. Doe in 1968 had focused attention on the site of JuIfar which lies just north of the present town of Ras a1 Khaimah (de Cardi, 1971, 230-2). Julfar was in existence in Abbasid times and its importance as an entrep6t during the sixteenth and seventeenth centuries-the Portuguese Period-is reflected by the quantity and variety of imported wares to be found among the ruins of the city. Most of the sites discovered during the survey dated from that period but a group of cairns near Ghalilah and some long gabled graves in the Shimal area to the north-east of the date-groves behind Ras a1 Khaimah (map, FIG. I) clearly represented a more distant past.

Sequencing Analysis and Phylogenetic Tree of HPV Isolated from Breast Cancer Patients at Thi-Qar Province/Iraq

2020 ◽  
pp. 37-40
Keyword(s):  
Nucleotide Sequence ◽  
Phylogenetic Tree ◽  
Evolutionary Relationship ◽  
Nucleotide Sequencing ◽  
Sequencing Analysis ◽  
Breast Cancer Patients ◽  
The North ◽  
Formalin Fixed Paraffin ◽  
Formalin Fixed Paraffin Embedded ◽  
History Of

Genetic variety examination has demonstrated fundamental to the understanding of the epidemiological and developmental history of Papillomavirus (HPV), for the development of accurate diagnostic tests and for efficient vaccine design. The HPV nucleotide diversity has been investigated widely among high-risk HPV types. To make the nucleotide sequence of HPV and do the virus database in Thi-Qar province, and compare sequences of our isolates with previously described isolates from around the world and then draw its phylogenetic tree, this study done. A total of 6 breast formalin-fixed paraffin-embedded (FFPE) of the female patients were included in the study, divided as 4 FFPE malignant tumor and 2 FFPE of benign tumor. The PCR technique was implemented to detect the presence of HPV in breast tissue, and the real-time PCR used to determinant HPV genotypes, then determined a complete nucleotide sequence of HPV of L1 capsid gene, and draw its phylogenetic tree. The nucleotide sequencing finding detects a number of substitution mutation (SNPs) in (L1) gene, which have not been designated before, were identified once in this study population, and revealed that the HPV16 strains have the evolutionary relationship with the South African race, while, the HPV33 and HPV6 showing the evolutionary association with the North American and East Asian race, respectively.

North American Association for the Study of Religion (NAASR)

2015 ◽  
Vol 44 (2) ◽  
pp. 29-30
Author(s):  
Matt Sheedy
Keyword(s):  
North American ◽  
American Association ◽  
The North ◽  
History Of

I interviewed Russell McCutcheon back in March 2015, about his new role as president of the North American Association for the Study of Religion (NAASR), asking him about the history of the organization, goals for his tenure, and developments for NAASR’s upcoming conference in Atlanta in November 2015.

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