A Semiparametric Characterization of Income Uncertainty Over the Life Cycle

James Feigenbaum;  ; Geng Li

doi:10.17016/feds.2010.42

A Semiparametric Characterization of Income Uncertainty Over the Life Cycle

SSRN Electronic Journal ◽

10.2139/ssrn.1895511 ◽

2010 ◽

Author(s):

Geng Li ◽

James A. Feigenbaum

Keyword(s):

Life Cycle ◽

Income Uncertainty

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CD25890, a conserved protein that modulates sporulation initiation in Clostridioides difficile

Scientific Reports ◽

10.1038/s41598-021-86878-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Diogo Martins ◽

Michael A. DiCandia ◽

Aristides L. Mendes ◽

Daniela Wetzel ◽

Shonna M. McBride ◽

...

Keyword(s):

Life Cycle ◽

Biofilm Formation ◽

Regulatory Protein ◽

Well Being ◽

Human Intestine ◽

Healthy Humans ◽

Clostridioides Difficile ◽

Nutritional Conditions ◽

Sporulation Initiation

AbstractBacteria that reside in the gastrointestinal tract of healthy humans are essential for our health, sustenance and well-being. About 50–60% of those bacteria have the ability to produce resilient spores that are important for the life cycle in the gut and for host-to-host transmission. A genomic signature for sporulation in the human intestine was recently described, which spans both commensals and pathogens such as Clostridioides difficile and contains several genes of unknown function. We report on the characterization of a signature gene, CD25890, which, as we show is involved in the control of sporulation initiation in C. difficile under certain nutritional conditions. Spo0A is the main regulatory protein controlling entry into sporulation and we show that an in-frame deletion of CD25890 results in increased expression of spo0A per cell and increased sporulation. The effect of CD25890 on spo0A is likely indirect and mediated through repression of the sinRR´ operon. Deletion of the CD25890 gene, however, does not alter the expression of the genes coding for the cytotoxins or the genes involved in biofilm formation. Our results suggest that CD25890 acts to modulate sporulation in response to the nutrients present in the environment.

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Pratylenchidae: Achlysiella, Hirschmanniella, Nacobbus, Pratylenchus, Radopholus and Zygotylenchus species.

10.1079/9781789247367.0011 ◽

2021 ◽

pp. 337-406

Author(s):

Ziaul Haque ◽

Mujeebur Rahman Khan

Keyword(s):

Life Cycle ◽

Risk Analysis ◽

Host Resistance ◽

Chemical Control ◽

Economic Importance ◽

Detailed Account ◽

Pest Risk Analysis ◽

Management Measures ◽

Pest Risk

Abstract This chapter provides information on geographical distribution; host plants; symptoms; biology and life cycle; economic importance; movement and means of dispersal; pest risk analysis; invasiveness rating; management measures, including cultural, host resistance, biological, and chemical control; and detailed account of diagnosis procedures, such as morphological, biochemical, and molecular characterization, of Achlysiella, Hirschmanniella, Nacobbus, Pratylenchus, Radopholus and Zygotylenchus species.

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Hoplolaimidae: Aphasmatylenchus, Helicotylenchus, Hoplolaimus and Scutellonema species.

10.1079/9781789247367.0008 ◽

2021 ◽

pp. 197-240

Author(s):

Ziaul Haque ◽

Mujeebur Rahman Khan

Keyword(s):

Life Cycle ◽

Risk Analysis ◽

Molecular Characterization ◽

Geographical Distribution ◽

Economic Importance ◽

Detailed Account ◽

Pest Risk Analysis ◽

Management Measures ◽

Pest Risk

Abstract This chapter provides information on geographical distribution; host plants; symptoms; biology and life cycle; economic importance; movement and means of dispersal; pest risk analysis; invasiveness rating; management measures; and detailed account of diagnosis procedures, such as morphological, biochemical, and molecular characterization, of Aphasmatylenchus, Helicotylenchus, Hoplolaimus and Scutellonema species.

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Belonolaimidae: Belonolaimus species.

10.1079/9781789247367.0004 ◽

2021 ◽

pp. 100-105

Author(s):

Ziaul Haque ◽

Mujeebur Rahman Khan

Keyword(s):

Life Cycle ◽

Risk Analysis ◽

Molecular Characterization ◽

Economic Importance ◽

Detailed Account ◽

Pest Risk Analysis ◽

Management Measures ◽

Wide Range ◽

Pest Risk

Abstract The sting nematode, Belonolaimus spp., is one of the most destructive nematode pests of turfgrass and attacks a wide range of monocotyledonous plants and gymnosperms, including vegetables, legumes, cereals, etc. This chapter includes information on: geographical distribution; host ranges; symptoms; biology and life cycle; ecology; physiological races; economic importance; invasiveness; pest risk analysis; movement and means of dispersal; management measures; and detailed account of diagnosis procedures, such as morphological, biochemical, cytogenetic and molecular characterization, of Belonolaimus species.

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Diptera of sanitary importance associated with composting of biosolids in Argentina

Revista de Saúde Pública ◽

10.1590/s0034-89102003000600006 ◽

2003 ◽

Vol 37 (6) ◽

pp. 722-728 ◽

Cited By ~ 8

Author(s):

Valeria Alejandra Labud ◽

Liliana Graciela Semenas ◽

Francisca Laos

Keyword(s):

Life Cycle ◽

Sex Ratio ◽

Musca Domestica ◽

Calliphora Vicina ◽

Immature Stages ◽

Community Characteristics ◽

Complete Life Cycle ◽

Phaenicia Sericata ◽

Composting Facilities

OBJECTIVE: Odorous compounds produced at the biosolids composting plant in Bariloche (NW Patagonia) attract a variety of insects, mainly belonging to the order Diptera. In order to characterize these flies, collected specimens were taxonomically identified, their community characteristics were described and their sanitary and synanthropic importance and autochthonous or introduced character were determined. METHODS: Sampling was performed from October 1999 until March 2000. Adults were collected using an entomological net, and larvae and puparia were obtained from the composting material and incubated to obtain adults. Richness, abundance and sex ratio were calculated. RESULTS: A total of 9 taxa of Diptera were identified: Sarconesia chlorogaster, Phaenicia sericata, Calliphora vicina, Cochliomya macellaria, Ophyra sp, Muscina stabulans, Musca domestica, Sarcophaga sp and Fannia sp. Specimens of Anthomyiidae, Acaliptratae and one larva of Eristalis tenax were also found. Ophyra sp. was the most abundant taxa. All the captured Diptera belonged to introduced taxa. Most of them are considered to be eusynanthropic and/or hemisynanthropic and have sanitary importance as they may cause myiasis and pseudomyiasis. The high number of females registered and the finding of immature stages indicated that flies can develop their complete life cycle on biosolid composting windrows. CONCLUSIONS: The characterization of flies obtained in this study may be useful for defining locations of urban or semi-urban composting facilities. It also highlights the importance of sanitary precautions at such plants.

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The Epigenetic Repertoire of Daphnia magna Includes Modified Histones

Genetics Research International ◽

10.1155/2012/174860 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 9

Author(s):

Nicole F. Robichaud ◽

Jeanette Sassine ◽

Margaret J. Beaton ◽

Vett K. Lloyd

Keyword(s):

Life Cycle ◽

Histone H3 ◽

Dependent Manner ◽

Nurse Cells ◽

Important Species ◽

Clonal Population ◽

A Cell ◽

Cycle Dependent

Daphnids are fresh water microcrustaceans, many of which follow a cyclically parthenogenetic life cycle. Daphnia species have been well studied in the context of ecology, toxicology, and evolution, but their epigenetics remain largely unexamined even though sex determination, the production of sexual females and males, and distinct adult morphological phenotypes, are determined epigenetically. Here, we report on the characterization of histone modifications in Daphnia. We show that a number of histone H3 and H4 modifications are present in Daphnia embryos and histone H3 dimethylated at lysine 4 (H3K4me2) is present nonuniformly in the nucleus in a cell cycle-dependent manner. In addition, this histone modification, while present in blastula and gastrula cells as well as the somatic cells of adults, is absent or reduced in oocytes and nurse cells. Thus, the epigenetic repertoire of Daphnia includes modified histones and as these epigenetic forces act on a genetically homogeneous clonal population Daphnia offers an exceptional tool to investigate the mechanism and role of epigenetics in the life cycle and development of an ecologically important species.

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Characterization of type IV pili in the life cycle of the predator bacterium Bdellovibrio

Microbiology ◽

10.1099/mic.0.036137-0 ◽

2010 ◽

Vol 156 (4) ◽

pp. 1040-1051 ◽

Cited By ~ 29

Author(s):

Khaled K. Mahmoud ◽

Susan F. Koval

Keyword(s):

Life Cycle ◽

Insoluble Fraction ◽

Type Iv Pili ◽

Host Cells ◽

Prey Cell ◽

Gram Negative ◽

Type Iv ◽

Genes Encoding ◽

Attack Phase

Bdellovibrio and like organisms (BALOs) are obligate prokaryotic predators of other Gram-negative bacteria. Bdellovibrio bacteriovorus is the most studied organism among BALOs. It has a periplasmic life cycle with two major stages: a motile, non-replicative stage spent searching for prey (the attack phase) and a stage spent inside the periplasm of the Gram-negative prey cell (the growth phase) after forming an osmotically stable body termed the bdelloplast. Within Bdellovibrio, there are also strains exhibiting an epibiotic life cycle. The genome sequence of the type strain B. bacteriovorus HD100T revealed the presence of multiple dispersed pil genes encoding type IV pili. Type IV pili in other bacteria are involved in adherence to and invasion of host cells and therefore can be considered to play a role in invasion of prey cells by Bdellovibrio. In this study, genes involved in producing type IV pili were identified in the periplasmic strain B. bacteriovorus 109J and an epibiotic Bdellovibrio sp. strain JSS. The presence of fibres on attack-phase cells was confirmed by examining negative stains of cells fixed with 10 % buffered formalin. Fibres were at the non-flagellated pole on approximately 25 % of attack-phase cells. To confirm that these fibres were type IV pili, a truncated form of PilA lacking the first 35 amino acids was designed to facilitate purification of the protein. The truncated PilA fused to a His-tag was overexpressed in Escherichia coli BL21(DE3) plysS. The fusion protein, accumulated in the insoluble fraction, was purified under denaturing conditions and used to produce polyclonal antisera. Immunoelectron microscopy showed that polar fibres present on the cell surface of the predator were composed of PilA, the major subunit of type IV pili. Immunofluorescence microscopy showed the presence of pilin on attack-phase cells of B. bacteriovorus 109J during attachment to prey cells and just after penetration, inside the bdelloplast. Antibodies against PilA delayed and inhibited predation in co-cultures of Bdellovibrio. This study confirms that type IV pili play a role in invasion of prey cells by Bdellovibrio.

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