Demography of Newfoundland populations of three Viola species

1983 ◽  
Vol 61 (10) ◽  
pp. 2581-2591 ◽  
Author(s):  
Sandra J. Newell
Keyword(s):  
Population Dynamics ◽  
Mortality Rate ◽  
Demographic Data ◽  
Plant Size ◽  
Plant Age ◽  
The Other ◽  
Seedling Density ◽  
Plant Survival ◽  
Density Effects ◽  
Mean Size

Demographic data were gathered on populations of Viola incognita Brainard, V. pallens (Banks) Brainard, and V. adunca Ait. in Newfoundland. Density, recruitment, and mortality varied within and among species; but most populations expanded tremendously during the 4-year study period. Increasing density in V. pallens and V. incognita populations resulted in decreasing mean size of ramets. Density effects on plant size in V. adunca were obscured by the addition of many small seedlings to the populations. Seedling density and survivorship were relatively high, and disturbance appears to play an important role in violet population dynamics. Relative plant age (i.e., cohort) and plant size seldom were associated with plant survival over a 1-year period. An association between plant size and survival existed in V. adunca only because one-leaf plants had a higher mortality rate than plants with two or more leaves. Low survivorship was associated with reproduction in V. incognita, but no such association existed in the other species. Levels of herbivory were low, and herbivory and subsequent survival over 1 year were not associated.

Influence of Egg Characteristics on Survival, Growth and Feeding in Larval Walleye (Stizostedion vitreum)

1989 ◽  
Vol 46 (3) ◽  
pp. 516-521 ◽  
Author(s):  
G. E. E. Moodie ◽  
N. L. Loadman ◽  
M. D. Wiegand ◽  
J. A. Mathias
Keyword(s):  
Fatty Acids ◽  
Mortality Rate ◽  
Growth Rates ◽  
Egg Size ◽  
The Other ◽  
Stizostedion Vitreum ◽  
Mean Size ◽  
Survival And Growth ◽  
The Mean ◽  
High Level

A subsample of eggs from 109 walleye (Stizostedion vitreum) from Crean Lake, Saskatchewan, was sieved soon after fertilization to yield four groups of eggs ranging in size from 4.86 to 5.62 mm3. Overall egg size tended to correspond to yolk and oil volumes. At hatching, larvae from the eggs with the least yolk and oil were significantly shorter than larvae from all other egg groups. At the end of the experiment, 13 d after hatching, the larvae from the eggs with the most yolk were significantly larger than larvae from the other egg groups. Differences in the mean amount of food ingested by larvae were related to initial egg size. The yolk of the smallest eggs was deficient in the (n-3) series of polyunsaturated fatty acids. Larvae from these small eggs had a high level of major body deformities and a mortality rate which reached 100% by day 10. Small egg size in itself did not appear disadvantageous; larvae from a different stock (Lake of the Prairies, Manitoba) which produced eggs with a mean size less than that of the smallest sieved eggs, had survival and growth rates comparable with those of the larger Crean Lake eggs.

scholarly journals Use tumor suppressor genes as biomarkers for diagnosis of non-small cell lung cancer

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chuantao Zhang ◽  
Man Jiang ◽  
Na Zhou ◽  
Helei Hou ◽  
Tianjun Li ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Mortality Rate ◽  
Tumor Suppressor ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Network Effects ◽  
Small Cell ◽  
The Other ◽  
Small Cell Lung ◽  
High Efficient

AbstractLung cancer is the leading cause of death worldwide. Especially, non-small cell lung cancer (NSCLC) has higher mortality rate than the other cancers. The high mortality rate is partially due to lack of efficient biomarkers for detection, diagnosis and prognosis. To find high efficient biomarkers for clinical diagnosis of NSCLC patients, we used gene differential expression and gene ontology (GO) to define a set of 26 tumor suppressor (TS) genes. The 26 TS genes were down-expressed in tumor samples in cohorts GSE18842, GSE40419, and GSE21933 and at stages 2 and 3 in GSE19804, and 15 TS genes were significantly down-expressed in tumor samples of stage 1. We used S-scores and N-scores defined in correlation networks to evaluate positive and negative influences of these 26 TS genes on expression of other functional genes in the four independent cohorts and found that SASH1, STARD13, CBFA2T3 and RECK were strong TS genes that have strong accordant/discordant effects and network effects globally impacting the other genes in expression and hence can be used as specific biomarkers for diagnosis of NSCLC cancer. Weak TS genes EXT1, PTCH1, KLK10 and APC that are associated with a few genes in function or work in a special pathway were not detected to be differentially expressed and had very small S-scores and N-scores in all collected datasets and can be used as sensitive biomarkers for diagnosis of early cancer. Our findings are well consistent with functions of these TS genes. GSEA analysis found that these 26 TS genes as a gene set had high enrichment scores at stages 1, 2, 3 and all stages.

scholarly journals The influence of two wildfires and biological control agents on the population dynamics of Melaleuca quinquenervia in a seasonally inundated wetland

2021 ◽  
Vol 14 (1) ◽  
pp. 3-8
Author(s):  
Philip W. Tipping ◽  
Melissa R. Martin ◽  
Jeremiah R. Foley ◽  
Ryan M. Pierce ◽  
Lyn A. Gettys
Keyword(s):  
Biological Control ◽  
Population Dynamics ◽  
Seedling Recruitment ◽  
Additional Treatment ◽  
Seed Rain ◽  
The Other ◽  
Melaleuca Quinquenervia ◽  
Biological Control Agents ◽  
Seedling Mortality ◽  
Sapling Growth

AbstractThe potential of Melaleuca quinquenervia (Cav.) S.T. Blake to reinvade cleared areas was evaluated over a 13-yr period that included two wildfires and the introduction of biological control agents. The first wildfire occurred in 1998 and was followed by a mean of 591.5 recruited seedlings m−2. Recruits from that fire were cleared 7 yr later in July 2005 for a second experiment to evaluate seedling recruitment into cleared areas. Seed rain, seedling recruitment and mortality, and sapling growth rates were measured in four plots located around individual large reproductive trees. A second natural wildfire in 2007 burned through those plots, leading to increases in seed rain followed by a pulse in recruitment of 21.04 seedlings m−2, 96.5% fewer than after the 1998 fire. Recruits in half of the plots around each tree were then treated with regular applications of an insecticide to restrict herbivory by biological control agents, while herbivory was not restricted in the other half. There was no difference in seedling mortality between treatments 1,083 d post-fire (2007) with 96.6% seedling mortality in the unrestricted herbivory treatment and 89.4% mortality in the restricted herbivory treatment. Recruits subjected to the restricted herbivory treatment grew taller than those in the unrestricted herbivory treatment, 101.3 cm versus 37.4 cm. Many of the recruits were attacked by the biological control agents, which slowed their growth. Although solitary M. quinquenervia trees retain some capacity to reinvade areas under specific circumstances, there was a downward trend in their overall invasiveness at this site, with progressively smaller recruitment cohorts due to biological control agents. Land managers should prioritize removing large reproductive trees over treating recently recruited populations, which can be left for many years for the biological control agents to suppress before any additional treatment would be needed.

scholarly journals Demographic effects of interacting species: exploring stable coexistence under increased climatic variability in a semiarid shrub community

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ana I. García-Cervigón ◽  
Pedro F. Quintana-Ascencio ◽  
Adrián Escudero ◽  
Merari E. Ferrer-Cervantes ◽  
Ana M. Sánchez ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Species Coexistence ◽  
Climatic Factors ◽  
Demographic Data ◽  
Climatic Variability ◽  
Biotic Interactions ◽  
Vital Rates ◽  
Climatic Fluctuations ◽  
Demographic Models ◽  
Shrub Community

AbstractPopulation persistence is strongly determined by climatic variability. Changes in the patterns of climatic events linked to global warming may alter population dynamics, but their effects may be strongly modulated by biotic interactions. Plant populations interact with each other in such a way that responses to climate of a single population may impact the dynamics of the whole community. In this study, we assess how climate variability affects persistence and coexistence of two dominant plant species in a semiarid shrub community on gypsum soils. We use 9 years of demographic data to parameterize demographic models and to simulate population dynamics under different climatic and ecological scenarios. We observe that populations of both coexisting species may respond to common climatic fluctuations both similarly and in idiosyncratic ways, depending on the yearly combination of climatic factors. Biotic interactions (both within and among species) modulate some of their vital rates, but their effects on population dynamics highly depend on climatic fluctuations. Our results indicate that increased levels of climatic variability may alter interspecific relationships. These alterations might potentially affect species coexistence, disrupting competitive hierarchies and ultimately leading to abrupt changes in community composition.

Prevalence of Hyponatremia and Its Associated Morbimortality in Hospitalized Patients Receiving Parenteral Nutrition

2017 ◽  
Vol 71 (1-2) ◽  
pp. 1-7 ◽  
Author(s):  
Emilia Gómez-Hoyos ◽  
Martín Cuesta ◽  
Nayade Del Prado-González ◽  
Pilar Matía ◽  
Natalia Pérez-Ferre ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Mortality Rate ◽  
Parenteral Nutrition ◽  
Demographic Data ◽  
Tertiary Hospital ◽  
Hospital Length ◽  
Hospitalized Patients ◽  
Hospital Length Of Stay ◽  
Control Subjects ◽  
Comorbidity Index

Background: The objective of the study was to determine the prevalence of hyponatremia (HN) and its associated morbimortality in hospitalized patients receiving parenteral nutrition (PN). Methods: A retrospective study including 222 patients receiving total PN (parenteral nutrition group [PNG]) over a 7-month period in a tertiary hospital and 176 matched to 179 control subjects without PN (control subjects group [CSG]). Demographic data, Charlson Comorbidity Index (CCI), date of HN detection-(serum sodium or SNa <135 mmol/L)-intrahospital mortality, and hospital length-of-stay (LOS) were registered. In the PNG, body mass index (BMI) and SNa before, during, and after PN were recorded. Results: HN was more prevalent in the PNG: 52.8 vs. 35.8% (p = 0.001), and independent of age, gender, or CCI (OR 1.8 [95% CI 1.1-2.8], p = 0.006). In patients on PN, sustained HN (75% of all intraindividual SNa <135 mmol/L) was associated with a higher mortality rate independent of age, gender, CCI, or BMI (OR 7.38 [95% CI 1.07-50.8], p = 0.042). The absence of HN in PN patients was associated with a shorter hospital LOS (<30 days) and was independent of other comorbidities (OR 3.89 [95% CI 2.11-7.18], p = 0.001). Conclusions: HN is more prevalent in patients on PN. Sustained HN is associated with a higher intrahospital mortality rate. Absence of HN is associated with a shorter hospital LOS.

Beta-Blocker Attenuates Cardiotoxicity Related Anthracycline Usage

2021 ◽  
Vol 104 (8) ◽  
pp. 1389-1392
Keyword(s):  
Side Effects ◽  
Cancer Therapy ◽  
Mortality Rate ◽  
Cancer Patients ◽  
Beta Blocker ◽  
The Other ◽  
Large Numbers ◽  
Therapy Effectiveness ◽  
Chemotherapy Agents

To summarize the recent trials and studies of the role of beta-blocker on the treatment for cancer patients treated with anthracycline to decrease morbidity and mortality rate. Good management of cancer will result in large numbers of cancer survivors. On the other hand, cancer therapy also has side effects, one of which is cardiotoxicity. Cardiotoxicity could reduce therapy effectiveness, hence, increase disease progression and mortality rate. Anthracyclines is one of the chemotherapy agents with cardiotoxicity as a side effect. Beta-blocker has the ability to reduce cardiotoxicity due to anthracyclines usage. Keywords: Beta-blocker; Cardiotoxicity; Anthracyclines

Demographic changes and savings behavior: the experience of a developing country

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ebrahim Rezaei
Keyword(s):  
Time Series ◽  
Demographic Data ◽  
Calculated Data ◽  
The Other ◽  
Demographic Changes ◽  
Savings Behavior ◽  
Content Type ◽  
Household Level ◽  
Savings Rate ◽  
The Government

PurposeThis paper aims to disclose the savings behavior of Iran's economy in the context of demographic transition.Design/methodology/approachEmploying a version of Ramsey-Cass-Koopmans growth model, this paper benefits from a broad range of data and variables which are mainly taken from the Central Bank of Iran's database. The study uses actual and calculated data to produce analogous simulated data. The data cover the 1970–2015 period. This long period provides an opportunity to simulate more valid time series. It is worth noting that due to the severe economic sanctions imposed on the Iran's economy, particularly after 2017, some most recent data have been obliterated from the sample.FindingsThe results, stemming from the simulated model, hint that; firstly, the population variable is a notable determinant of the savings rate. Secondly, the effects of a slump in the population growth rate would attenuate the savings level significantly. Thirdly, other pragmatic steps could be taken to redress the fallout of the demographic changes.Research limitations/implicationsThere are some limitations in providing broad data related to economic sectors in Iran. The savings data, for instance, are available as an aggregated time series, and if the authors had wide data of household level, they would have been able to build more detail-based model. Similar to this issue of lack of households’ income-based data, some measures such as high or low levels as well as detailed demographic data could be helpful in sophisticated household level resulting. In addition, the complex relationship between the government and social security (pension) funds, in terms of financing part of government's budget deficit by these funds, thwarts a typical researcher in using comprehensive and transparent government expenditure data in their research. In other words, the possible positive or negative role of the funds, as a related issue to the demographic changes, cannot simply be determined in the model. It might be possible after necessary corrections are carried out in the mentioned relations.Originality/valueIn fact, the problem statement in this paper is to discern how the population aging can impact the saving rates on the one hand, and to what extent its repercussion can be modified by the other theoretical-based determinants on the other. In fact, the underlying argument of the present research arises from the stylized facts concerning prognosticates of the future evolutions of the world's population. To that end, the study will use Iran's economic and demographic data.

scholarly journals Morbidity and mortality after fragility hip fracture in a Saudi Arabian population: Report from a single center

2017 ◽  
Vol 45 (3) ◽  
pp. 1175-1180 ◽  
Author(s):  
Mir Sadat-Ali ◽  
Moaad Alfaraidy ◽  
Abdulaziz AlHawas ◽  
Ahmed Abdallah Al-Othman ◽  
Dakheel A Al-Dakheel ◽  
...  
Keyword(s):  
Hip Fracture ◽  
Mortality Rate ◽  
Demographic Data ◽  
Femoral Fractures ◽  
Morbidity And Mortality ◽  
High Morbidity ◽  
Fragility Hip Fracture ◽  
Asa Score ◽  
Telephone Interviews ◽  
American Society

Objective To determine the functional morbidity and mortality after fragility hip fracture and compare the mortality with three other common diseases. Methods Data were collected from patients admitted to King Fahd Hospital of the University, AlKhobar from January 2010 to December 2014. Demographic data included the preoperative American Society of Anesthesiologists (ASA) score as assessed by the anesthetist and the type of surgery. Personal and telephone interviews were performed, and data were entered into a database and analyzed. Results We identified 203 patients with fragility proximal femoral fractures, and the data of 189 patients (109 male, 80 female; average age, 66.90 ± 13.43 years) were available for analysis. The overall mortality rate was 26.98% (51 patients). The mortality rate was significantly higher among patients with an ASA score of 4 (36.36%) than 1 (20.45%). With respect to morbidity, only 48.23% of patients were able to return to their pre-fracture status; 32.35% of those who required assisted walking and 83.4% of those who required a wheelchair became bedridden. Conclusions Our data demonstrate that patients with fragility hip fractures have high morbidity and a mortality rate approaching 30%. Age and the ASA score significantly influence this high mortality rate.

scholarly journals Transferrin-Conjugated SNALPs Encapsulating 2′-O-Methylated miR-34a for the Treatment of Multiple Myeloma

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Immacolata Scognamiglio ◽  
Maria Teresa Di Martino ◽  
Virginia Campani ◽  
Antonella Virgilio ◽  
Aldo Galeone ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Zeta Potential ◽  
Lipid Vesicles ◽  
Significant Inhibition ◽  
The Other ◽  
Transferrin Receptors ◽  
Proof Of Concept ◽  
Wild Type ◽  
Chemical Conjugation ◽  
Mean Size

Stable nucleic acid lipid vesicles (SNALPs) encapsulating miR-34a to treat multiple myeloma (MM) were developed. Wild type or completely 2′-O-methylated (OMet) MiR-34a was used in this study. Moreover, SNALPs were conjugated with transferrin (Tf) in order to target MM cells overexpressing transferrin receptors (TfRs). The type of miR-34a chemical backbone did not significantly affect the characteristics of SNALPs in terms of mean size, polydispersity index, and zeta potential, while the encapsulation of an OMet miR-34a resulted in a significant increase of miRNA encapsulation into the SNALPs. On the other hand, the chemical conjugation of SNALPs with Tf resulted in a significant decrease of the zeta potential, while size characteristics and miR-34a encapsulation into SNALPs were not significantly affected. In an experimental model of MM, all the animals treated with SNALPs encapsulating miR-34a showed a significant inhibition of the tumor growth. However, the use of SNALPs conjugated with Tf and encapsulating OMet miR-34a resulted in the highest increase of mice survival. These results may represent the proof of concept for the use of SNALPs encapsulating miR-34a for the treatment of MM.

The population dynamics of metacercariae of Apatemon gracilis (Trematoda: Digenea) in three species of lake-dwelling leeches

Parasitology ◽  
1986 ◽  
Vol 93 (3) ◽  
pp. 517-530 ◽  
Author(s):  
S. M. Spelling ◽  
J. O. Young
Keyword(s):  
Population Dynamics ◽  
Relative Density ◽  
Sexual Maturity ◽  
Egg Production ◽  
Seasonal Pattern ◽  
Distinct Pattern ◽  
The Other ◽  
Mean Intensity ◽  
Density Values ◽  
Host Mortality

SUMMARYMonthly samples of the leeches Erpobdella octoculata, Glossiphonia complanata and Helobdella stagnalis were taken over a two-year period from an eutrophic, English lake to detect metacercariae of the trematode, Apatemon gracilis. In each cohort of each of the three leeches, prevalence was low in young individuals, rose to a peak in autumn/winter, and then declined until the cohort had almost died out; in E. octoculata and H. stagnalis a final brief increase occurred. Mean intensity and relative density values followed a similar seasonal pattern of change to that of prevalence in these last two species, but in G. complanata values fluctuated irregularly with no distinct pattern. The frequency distribution of the parasite in G. complanata was highly over-dispersed, but less so in the other two species. Infected E. octoculata reached sexual maturity. The parasite reduced egg production in G. complanata and H. stagnalis, but only by maximum values of 2·5 and 9% respectively. This reduction in fecundity is low compared to the subsequent high mortality, at 95% or more, of newly recruited young from as yet unidentified causes. Parasite-related host mortality was difficult to assess in young leeches, but there was some evidence for its occurrence in older leeches of E. octoculata and H. stagnalis. However, this is unlikely to play a prominent role in the control and regulation of lacustrine leech populations.

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