Life tables: construction and interpretation

2021 ◽  
pp. 151-162
Author(s):  
Owen R. Jones
Keyword(s):  
Life Histories ◽  
Worked Examples ◽  
Time Frame ◽  
Life Tables ◽  
Type I ◽  
Type Ii ◽  
Risk Of Death ◽  
Nonhuman Animals ◽  
Using Data ◽  
Diversity Of Life

Life tables, which describe how the risk of death (and sometimes fertility) changes with age, are a fundamental tool for describing and exploring the diversity of life histories. Numerous important life history metrics can be derived from them. This chapter provides a broad coverage of life table construction and use and use with a particular focus on nonhuman animals. The calculation of life tables can be divided into approaches: cohort-based, where the data are obtained from individuals born at (approximately) the same time that are followed until death; and period-based, where the data are obtained from a population of mixed ages followed for a particular time-frame (e.g. a year). Worked examples of both approaches are provided using data from published sources. Emphasis is placed on understanding concepts such as rates vs. probability, life expectancy, and generation time. Links are drawn between the survivorship curve (type I, type II, and type III survivorship) and entropy. The chapter also covers the concept of the Lexis diagram which is used to represent births and deaths for individuals in different cohorts. Finally, the assumptions and limitations of life tables are discussed, with pointers to further reading. Code and data are provided.

An economic model comparison of EMSI and IMPLAN

2016 ◽  
Vol 23 (5) ◽  
pp. 1124-1130 ◽  
Author(s):  
Sungsoo Kim ◽  
Chad R. Miller
Keyword(s):  
Model Comparison ◽  
Impact Analysis ◽  
Economic Modeling ◽  
Total Output ◽  
Type I ◽  
Type Ii ◽  
Development Research ◽  
Tourism Research ◽  
Multiplier Effects ◽  
Using Data

Economic Modeling Specialist International (EMSI) model is a common economic development research tool that has begun to be utilized for tourism research. Therefore, it is important to examine the differences between the EMSI model and the commonly used Impact Analysis for Planning (IMPLAN) model. The multiplier effects of the default version of EMSI and IMPLAN were compared using data obtained from a visitor expenditure survey of the Jackson Mississippi Mistletoe Marketplace. The results revealed that IMPLAN estimated larger multiplier effects (both type I and type II) than EMSI for the total output and employment (job supports).

En Explorativ Studie av Några Alkoholisters Livshistoria Från 1940- Till 1990-Talet

1995 ◽  
Vol 12 (4) ◽  
pp. 194-202
Author(s):  
Leif Öjesjö
Keyword(s):  
Longitudinal Study ◽  
Mental Disorder ◽  
Life Histories ◽  
Type I ◽  
Type Ii ◽  
Current Alcohol

In this longitudinal study of alcoholics from the Lundby Project, five life histories have been constructed from interviews and records, with the data covering several decades, from the 40's to the 90's. In order “to look behind the statistics”, the findings are discussed in the light of current alcohol research. The main themes include alcoholism as a career, type I and type II alcoholism, mental disorder, and life crises.

Race-driven survival differential in women diagnosed with endometrial cancers in the USA

2020 ◽  
Vol 30 (12) ◽  
pp. 1893-1901
Author(s):  
Zachary D Horne ◽  
Solomiya R Teterichko ◽  
Scott M Glaser ◽  
Rodney E Wegner ◽  
Shaakir Hasan ◽  
...  
Keyword(s):  
African American ◽  
African American Women ◽  
Type I ◽  
Type Ii ◽  
American Women ◽  
Risk Of Death ◽  
Asian Pacific Islander ◽  
Caucasian Women ◽  
Asian Pacific ◽  
Pacific Islander Women

ObjectiveAfrican American women are increasingly being diagnosed with advanced and type II histology endometrial cancers. Outcomes have been observed to be worse in African American women, but whether or not race itself is a factor is unclear. We sought to evaluate the rates of diagnosis and outcomes on a stage-by-stage basis with respect to race using a large national cancer registry database.MethodsThe National Cancer Data Base was searched for patients with surgically staged non-metastatic endometrial cancer between 2004 and 2015. Women were excluded if surgical stage/histology was unknown, there was no follow-up, or no information on subsequent treatment. Pairwise comparison was used to determine temporal trends and Cox hazards tests with Bonferroni correction were used to determine overall survival.ResultsA total of 286 920 women were diagnosed with endometrial cancer and met the criteria for analysis. Median follow-up was 51 months (IQR 25.7–85.3). In multivariable models, in women with stage I disease, African American women had a higher risk of death than Caucasian women (HR 1.262, 95% CI 1.191 to 1.338, p<0.001) and Asian/Pacific Islander women had a lower risk of death than Caucasian women (HR 0.742, 95% CI 0.689 to 0.801, p<0.001). This held for African American women with stage II type I and type II disease (HR 1.26, 95% CI 1.109 to 1.444, p<0.001 and HR 1.235, 95% CI 1.098 to 1.388, p<0.001) but not for Asian/Pacific Islander women. African American women with stage IIIA–B disease also had a higher risk of death for type I and type II disease versus Caucasian women (HR 1.221, 95% CI 1.045 to 1.422, p=0.010 and HR 1.295, 95% CI 1.155 to 1.452, p<0.001). Asian/Pacific Islander women had a lower risk of death than Caucasian women with type I disease (HR 0.783, 95% CI 0.638 to 0.960, p=0.019) and type II disease (HR 0.790, 95% CI 0.624 to 0.999, p=0.05). African American women with stage IIIC1–2 had a higher risk of death with type I disease (HR 1.343, 95% CI 1.207 to 1.494, p<0.001) and type II disease (HR 1.141, 95% CI 1.055 to 1.233, p=0.001) whereas there was no significant difference between Caucasian women and Asian/Pacific Islander women.ConclusionRace appears to play an independent role in survival from endometrial cancer in the USA, with African American women having worse survival on a stage-for-stage basis compared with Caucasian women.

scholarly journals Diversity and dynamics of the CRISPR-Cas systems associated with Bacteroides fragilis in human population

2021 ◽  
Author(s):  
Tony J. Lam ◽  
Kate Mortensen ◽  
Yuzhen Ye
Keyword(s):  
Human Population ◽  
Population Genomics ◽  
Parallel Evolution ◽  
Mobile Elements ◽  
Type I ◽  
Type Ii ◽  
Holistic View ◽  
Network Modules ◽  
Using Data ◽  
Adaptive Immune Systems

AbstractThe CRISPR-Cas systems are important prokaryotic adaptive immune systems and effectively record the arms-race between bacteria and invading mobile elements in their CRISPR arrays. Using data from culture-based population genomics and metagenomics, we investigated the CRISPR-Cas systems associated with Bacteriodes fragilis, an important gut bacterium, and studied their diversity and dynamics. We analyzed genomes of 601 B. fragilis isolates derived from 12 healthy individuals, among which include time-series isolates from 6 individuals. In addition, we analyzed 222 reference B. fragilis genomes. Three different types of CRISPR-Cas systems (Type I-B, II-C and III-B) were found in analyzed B. fragilis genomes, with Type III-B being the most prevalent whereas the Type II-C being the most dynamic with varying arrays among isolates. Our graph-based summary and visualization of CRISPR arrays provided a holistic view of the organization and the composition of the CRISPR spacers. We observed insertions of different new spacers at the leader ends of the CRISPR arrays of Type II-C CRISPR-Cas systems in different B. fragilis sub-populations in one individual, an example of B. fragilis’ adaptation and parallel evolution within individual microbiomes. A network of B. fragilis and its predicted invaders also revealed microdynamics of B. fragilis CRISPR array, with hairball-like structures representing spacers with multi-target capabilities and network modules revealing the collective targeting of selected mobile elements by many spacers. This work demonstrates the power of using culture-based population genomics to reveal the activities and evolution of the CRISPR-Cas systems of the important gut bacterium B. fragilis in human population.

OIL SPILL MONITORING HANDBOOK

2005 ◽  
Vol 2005 (1) ◽  
pp. 937-941
Author(s):  
Leigh Stevens ◽  
John Wardrop
Keyword(s):  
Oil Spill ◽  
Monitoring Program ◽  
Time Frame ◽  
Environmental Damage ◽  
Type I ◽  
Type Ii ◽  
Termination Criteria ◽  
Monitoring Programs ◽  
Key Issues ◽  
Response Decisions

ABSTRACT This paper describes afield handbook jointly prepared for the New Zealand (NZ) Maritime Safety Authority (MSA) and Australian MSA (AMSA) to help plan the scope, scale, and design of oil spill monitoring programs. A two-class monitoring nomenclature is used to classify monitoring according to its underlying purpose. Type I (Operational) Monitoring: provides information of direct relevance to spill response operations, i.e. information needed to plan or execute response or cleanup strategies. Type II (Scientific) Monitoring: relates to non-response objectives, i.e. short and long term environmental damage assessments (including recovery), purely scientific studies, and all post spill monitoring activities. The two-class monitoring nomenclature recognizes the very different objectives of Type I and Type II monitoring, and the methods, scope, and degree of scientific rigour required for each. These in turn, have a significant bearing on the cost of the monitoring, and who will pay for it. Currently, Type I monitoring costs are recovered in NZ and Australia from the spiller (or insurer) alongside other operational response costs. The handbook, formatted as a field pocket guide, provides specific guidance as to what may be considered “necessary” and “reasonable” Type I monitoring, as well as presenting guidelines for defining study objectives, spatial boundaries, monitoring parameters, sampling and assessment methods, study duration, logistics, design constraints (and solutions), resources, and termination criteria. Type II monitoring programs are usually not integral to the response, and funding is less well defined, so Type II monitoring is not specifically addressed in the Handbook. However, many of the Type I guidelines are also relevant for Type II studies. The Handbook is intended to provide responders with sufficient guidance to determine the type of information necessary for an operational spill response, and an overview of the methods commonly used to collect the information needed to reach defensible spill response decisions in an appropriate time frame, and with an acceptable level of accuracy. The Handbook is supported by a Background Paper describing the key issues to be considered in establishing a monitoring program.

Heat-Etching with a Bullivant Type II Simple Freeze-Cleave Device

1970 ◽  
Vol 28 ◽  
pp. 106-107 ◽  
Author(s):  
Ronald S. Weinstein ◽  
N. Scott McNutt
Keyword(s):  
New Zealand ◽  
General Hospital ◽  
Massachusetts General Hospital ◽  
Type I ◽  
Type Ii ◽  
Collaborative Effort ◽  
Temperature And Pressure ◽  
The University

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.

Labelling of non-A, non-B hepatitis infected chimpanzee hepatocytes with nuclease-gold conjugates

1984 ◽  
Vol 42 ◽  
pp. 250-251
Author(s):  
G. D. Gagne ◽  
M. F. Miller ◽  
D. A. Peterson
Keyword(s):  
Endoplasmic Reticulum ◽  
Experimental Infection ◽  
Uranyl Acetate ◽  
Type I ◽  
Cellular Injury ◽  
Type Ii ◽  
Tubular Structures ◽  
Type Iii ◽  
Type Iv ◽  
Infected Chimpanzee

Experimental infection of chimpanzees with non-A, non-B hepatitis (NANB) or with delta agent hepatitis results in the appearance of characteristic cytoplasmic alterations in the hepatocytes. These alterations include spongelike inclusions (Type I), attached convoluted membranes (Type II), tubular structures (Type III), and microtubular aggregates (Type IV) (Fig. 1). Type I, II and III structures are, by association, believed to be derived from endoplasmic reticulum and may be morphogenetically related. Type IV structures are generally observed free in the cytoplasm but sometimes in the vicinity of type III structures. It is not known whether these structures are somehow involved in the replication and/or assembly of the putative NANB virus or whether they are simply nonspecific responses to cellular injury. When treated with uranyl acetate, type I, II and III structures stain intensely as if they might contain nucleic acids. If these structures do correspond to intermediates in the replication of a virus, one might expect them to contain DNA or RNA and the present study was undertaken to explore this possibility.

Comparative surface and ultrastructural views of methylotrophic bacteria by TEM, STEM, SE, and freeze-etch electron microscopy.

1987 ◽  
Vol 45 ◽  
pp. 792-793
Author(s):  
T.A. Fassel ◽  
M.J. Schaller ◽  
M.E. Lidstrom ◽  
C.C. Remsen
Keyword(s):  
Cytoplasmic Membrane ◽  
Structural Features ◽  
Methylotrophic Bacteria ◽  
Type I ◽  
Type Ii ◽  
Membrane Complex ◽  
Oxidation Of Methane ◽  
Methane Oxidizing Bacteria ◽  
Wall Structures ◽  
Methylomonas Albus

Methylotrophic bacteria play an Important role in the environment in the oxidation of methane and methanol. Extensive intracytoplasmic membranes (ICM) have been associated with the oxidation processes in methylotrophs and chemolithotrophic bacteria. Classification on the basis of ICM arrangement distinguishes 2 types of methylotrophs. Bundles or vesicular stacks of ICM located away from the cytoplasmic membrane and extending into the cytoplasm are present in Type I methylotrophs. In Type II methylotrophs, the ICM form pairs of peripheral membranes located parallel to the cytoplasmic membrane. Complex cell wall structures of tightly packed cup-shaped subunits have been described in strains of marine and freshwater phototrophic sulfur bacteria and several strains of methane oxidizing bacteria. We examined the ultrastructure of the methylotrophs with particular view of the ICM and surface structural features, between representatives of the Type I Methylomonas albus (BG8), and Type II Methylosinus trichosporium (OB-36).

Heteroscedastic Methods for Performing All Pairwise Comparisons of Regression Lines Associated With J Independent Groups

Methodology ◽  
2015 ◽  
Vol 11 (3) ◽  
pp. 110-115 ◽  
Author(s):  
Rand R. Wilcox ◽  
Jinxia Ma
Keyword(s):  
Least Squares ◽  
Pairwise Comparisons ◽  
Simple Extension ◽  
Type I ◽  
Type I Errors ◽  
Well Elderly ◽  
Using Data

Abstract. The paper compares methods that allow both within group and between group heteroscedasticity when performing all pairwise comparisons of the least squares lines associated with J independent groups. The methods are based on simple extension of results derived by Johansen (1980) and Welch (1938) in conjunction with the HC3 and HC4 estimators. The probability of one or more Type I errors is controlled using the improvement on the Bonferroni method derived by Hochberg (1988) . Results are illustrated using data from the Well Elderly 2 study, which motivated this paper.

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