4,074 research outputs found
First report of Metarhizium anisopliae IP 46 pathogenicity in adult Anopheles gambiae s.s. and An. arabiensis (Diptera; Culicidae).
No full textThe entomopathogenic fungus Metarhizium anisopliae isolate IP 46, originating from a soil sample collected in 2001 in the Cerrado of Central Brazil, was tested for its ability to reduce the survival of adult male and female Anopheles gambiae s.s. and An. arabiensis mosquitoes. A 6-h exposure to the fungus coated on test paper at a concentration of 3.3 x 106 conidia cm-2 reduced the daily survival of both mosquito species (HR = 3.14, p < 0.001), with higher risk of dying in An. gambiae s.s relative to An. arabiensis (HR = 1.38, p < 0.001). Fungal sporulation was observed in >95% of mosquito cadavers in the treatment groups. The results indicate that M. anisopliae IP 46 has the potential to be a bio-control agent for African malaria vector species, and is a suitable candidate for further research and development
Siles, S.S., Letter to Mary Knight, September 20, 1863
No full textStiles, S.S., Letter to Mary Knight, September 20, 1863. MS/52 William Knight Civil War Letters, Box 1, Folder 3. Valdosta State University Archives and Special Collections. 1 PDF and 2 scans. Includes transcript.The letter, dated September 20, 1863, is from Camp Lee and addressed to Mary. The author, identified as S.S. Siles, expresses relief that William has returned home and hopes for his quick recovery. Siles mentions the difficulties faced by women who visit camps to bring their sick husbands home, noting that officers rarely pay them any attention.
Siles laments the poor condition of the tents, which are old and worn, failing to provide adequate shelter from rain. He mentions that the Quarter Master tried but failed to secure new tents in Savannah. The letter also touches on the precarious state of the Confederate army, suggesting that its future may hinge on an upcoming battle in Northern Georgia. Siles fears that a defeat could lead to mass desertions.
The letter describes the men as being very sickly, attributing this to their poor diet of only beef and cornmeal. Siles himself is not in good health, suffering from chest pains and fevers, but continues to perform his duties as an acting Orderly Sergeant. He urges Mary to tell William to write to him and to keep him updated with news
Declaration of Intention for Orazio Colletto
No full textDeclaration of Intention to become a citizen of the United States, as filled out and signed by Orazio Colletto. Applicant lists himself as a 58 year old farmer residing in Hammonton, New Jersey, born in Bordenaro, Italy on 17 January 1857, who sailed on the US bound vessel S.S. Prince. Declaration submitted and sworn June 3, 1915
Transient population dynamics of mosquitoes during sterile male releases : modelling mating behaviour and perturbations of life history parameters
No full textThe release of genetically-modified or sterile male mosquitoes offers a promising form of mosquito-transmitted pathogen control, but the insights derived from our understanding of male mosquito behaviour have not fully been incorporated into the design of such genetic control or sterile-male release methods. The importance of aspects of male life history and mating behaviour for sterile-male release programmes were investigated by projecting a stage-structured matrix model over time. An elasticity analysis of transient dynamics during sterile-male releases was performed to provide insight on which vector control methods are likely to be most synergistic. The results suggest that high mating competitiveness and mortality costs of released males are required before the sterile-release method becomes ineffective. Additionally, if released males suffer a mortality cost, older males should be released due to their increased mating capacity. If released males are of a homogenous size and size-assortative mating occurs in nature, this can lead to an increase in the abundance of large females and reduce the efficacy of the population-suppression effort. At a high level of size-assortative mating, the disease transmission potential of the vector population increases due to male releases, arguing for the release of a heterogeneously-sized male population. The female population was most sensitive to perturbations of density-dependent components of larval mortality and female survivorship and fecundity. These findings suggest source reduction might be a particularly effective complement to mosquito control based on the sterile insect technique (SIT). In order for SIT to realize its potential as a key component of an integrated vector-management strategy to control mosquito-transmitted pathogens, programme design of sterile-male release programmes must account for the ecology, behaviour and life history of mosquitoes. The model used here takes a step in this direction and can easily be modified to investigate additional aspects of mosquito behaviour or species-specific ecology
A reliable morphological method to assess the age of male <i>Anopheles gambiae</i>
No full text<b>Background</b>
Release of genetically-modified (GM) or sterile male mosquitoes for malaria control is hampered by inability to assess the age and mating history of free-living male <i>Anopheles</i>.
<b>Methods</b>
Age and mating-related changes in the reproductive system of male <i>Anopheles</i> gambiae were quantified and used to fit predictive statistical models. These models, based on numbers of spermatocysts, relative size of sperm reservoir and presence/absence of a clear area around the accessory gland, were evaluated using an independent sample of mosquitoes whose status was blinded during the experiment.
<b>Results</b>
The number of spermatocysts in male testes decreased with age, and the relative size of their sperm reservoir increased. The presence of a clear area around accessory glands was also linked to age and mating status. A quantitative model was able to categorize males from the blind trial into age groups of young (≤ 4 days) and old (> 4 days) with an overall efficiency of 89%. Using the parameters of this model, a simple table was compiled that can be used to predict male age. In contrast, mating history could not be reliably assessed as virgins could not be distinguished from mated males.
<b>Conclusion</b>
Simple assessment of a few morphological traits which are easily collected in the field allows accurate age-grading of male An. gambiae. This simple, yet robust, model enables evaluation of demographic patterns and mortality in wild and released males in populations targeted by GM or sterile male-based control programmes
FIGURE 7. A, male Ixodes affinis s.s in Description of two new species in the Ixodes ricinus complex from the New World (Acari: Ixodidae), and redescription of Ixodes affinis Neumann, 1899
No full textFIGURE 7. A, male Ixodes affinis s.s., dorsal view; B, male Ixodes affinis s.s., ventral view; C, male Ixodes affinis s.s., capitulum (ventral view) and coxae I and II; D, female Ixodes affinis s.s., dorsal view; E, female Ixodes affinis s.s., ventral view; F, female Ixodes affinis s.s., capitulum (ventral view) and coxae I and II.Published as part of <i>Nava, Santiago, Beati, Lorenza, Venzal, Jose M., Durden, Lance A., Bermudez, Sergio E., Tarragona, Evelina L., Mangold, Atilio J., Gleason, Debbie, Mastropaolo, Mariano & Guglielmone, Alberto A., 2023, Description of two new species in the Ixodes ricinus complex from the New World (Acari: Ixodidae), and redescription of Ixodes affinis Neumann, 1899, pp. 53-73 in Zootaxa 5361 (1)</i> on page 61, DOI: 10.11646/zootaxa.5361.1.2, <a href="http://zenodo.org/record/10150271">http://zenodo.org/record/10150271</a>
The genetics and ecology of male reproductive investments in the malaria mosquito Anopheles gambiae s.s
No full textMalaria continues to be a major global health problem due to high mortality and morbidity rate in endemic regions. An. gambiae s.s is the major vector in endemic African countries. About 198 million cases of malaria were recorded globally in 2013 and this have led to over 584 000 deaths. Different measures have been implemented in order to reduce and control the transmission rate. However, the drug resistant parasites and insecticide resistant mosquitoes have created problems towards achieving this goal. The use of the sterile insect technique and genetically modified mosquitoes as a control measure seems very promising but requires massive releases of males that are vigorous and competitive for the strategy to be realistic. Thus, there is need to understand the genetics and ecology of male mosquitoes with reference to their reproductive investments particularly for the laboratory reared An. gambiae due to inbreeding effects in colonized strains. Here we developed a qPCR technique based on TaqMan assay to quantify male sperm investment and used the assay to examine the effects of hydric stress on sperm investment by males and sperm maintenance in mated females. From two inbred strains of An. gambiae s.s, we generated heterotic supermales and tested for inbreeding and heterosis effects on sex peptide and sperm investments by males in large and individual male mating cages to determine male reproductive success. No evidence of heterosis was found in the large group mating cages except in sperm activity. However, in the individual male mating cages, the heterotic supermales achieved higher reproductive success than the inbred strains. They produced more eggs and fathered numerous larvae. Furthermore, inbreeding affects the size of the sex peptide deposited and survival in inbred males. Conclusively, heterosis could be the quickest method to produce vigorous and competitive laboratory reared males for vector control projects where male reproductive success is required
ZAVIČAJNO OPREDJELJENJE S.S. KRANJČEVIĆA
No full textHrvatski pjesnik S.S. Kranjčević (1865-1908), iako stvaralac nacionalnih i univerzalnih dimenzija, u određenom broju svojih pjesama iskazivao je na osebujan način svoje zavičajno određenje. Te njegove pjesme prožete snažnim emocijskim nabojima predočavaju njegovo viđenje ondašnje hrvatske nacionalne sudbine na prostoru njegova rodnog grada Senja u kontekstu uskočke tradicije koja je Senjane i Hrvate toliko nadahnjivala slobodarstvom i otporom tuđinskim porobljivačkim nasrtajima.The Croatian poet S.S. Kranjčević (1865-1908), though an author of national and universal dimensions, expressed his own native disposition in a number of his poems. Those of his poems, which are imbued with a strong emotional charge, present his own seeing of the Croatian national desetiny of the time in the area of his native town of Senj, and in the context of the Uskok (fighters against the Venetians and Turks) tradition which so much insipred the inhabitants (of Senj) and Croats in general with the love of freedom and resistance to the foreign enslaving assaults
Effects of age and size on Anopheles gambiae s.s. male mosquito mating success.
No full textBefore the release of genetically-modified or sterile male mosquitoes in an attempt to control local populations of malaria vectors, it is crucial to determine male traits involved in mating success. The effects of male size and age as determinants of male mating success in Anopheles gambiae s.s. were measured in the field and under laboratory conditions in Burkina Faso. First, the body sizes (estimated by wing length) of mating, swarming, and indoor-resting male mosquitoes were compared over a 3-yr period (2006-2009) from July to October in Soumousso and Vallée du Kou, two villages in western Burkina Faso. Second, the age structure of swarming and resting male mosquitoes were characterized based on the number of spermatocysts and the proportion of sperm in the reservoir of wild-caught male testis. Third, male age effects on the insemination rate of female An. gambiae were investigated in the laboratory. The mean size of males collected in copula was significantly larger than the mean for swarming males and indoor-resting males. The optimum male age for successful insemination of females was 4-8 d. These results suggest that male size is an important trait in determining male mating competitiveness in the field. Although age was not found to be a significant factor in mating competitiveness, it was significantly correlated with swarming behaviors in the field and insemination success in the laboratory. The implications of these results in terms of sexual selection in An. gambiae and vector control programs are further discussed
Real-space Manifestations of Bottlenecks in Turbulence Spectra
No full textAn energy-spectrum bottleneck, a bump in the turbulence spectrum between the inertial and dissipation ranges, is shown to occur in the non-turbulent, one-dimensional, hyperviscous Burgers equation and found to be the Fourier-space signature of oscillations in the real-space velocity, which are explained by boundary-layer-expansion techniques. Pseudospectral simulations are used to show that such oscillations occur in velocity correlation functions in one- and three-dimensional hyperviscous hydrodynamical equations that display genuine turbulence
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