scholarly journals Tolerance to a Combination of Low Temperature and Sterilizing Irradiation in Male Glossina palpalis gambiensis (Diptera: Glossinidae): Simulated Transport and Release Conditions

2019 ◽  
Vol 19 (5) ◽  
Author(s):  
Gratian N Mutika ◽  
Andrew G Parker ◽  
Marc J B Vreysen

Abstract Recently, aerial delivery of sterilized adult tsetse flies has been developed based on the release of chilled adult sterile males. The long-distance transport of irradiated male tsetse pupae for chilled adult release systems requires exposure of the mature pupae to irradiation and to low temperatures for both the pupae and adults. The effect of these treatments on mating of adult Glossina palpalis gambiensis (Vanderplank, Diptera: Glossinidae) males was investigated. Male G. p. gambiensis pupae were stored at 10°C for 5 d and irradiated with 110 Gy within the first 24 h of cold storage. In addition, to simulate a chilled adult release environment, 6-d-old adult males were stored at 5.1 ± 0.4°C for 6 or 30 h. Mating performance was compared to untreated controls in walk-in field cages. A significantly lower proportion of males that had been irradiated and stored at low temperature succeeded in securing a mating compared to untreated males. Premating time, copulation duration and spermathecal fill were similar. Insemination levels were slightly lower for adult males stored at low temperature for 30 h compared to 6 h or control. Although the mating behavior of the males was affected by the treatments given, the data presented confirm the suitability of using long-distance transport of chilled and irradiated male G. p. gambiensis pupae followed by releasing the emerged adult male flies using a chilled adult release system. However, the data indicate that the chilling duration of the adults should be minimized.

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Soumaïla Pagabeleguem ◽  
Momar Talla Seck ◽  
Baba Sall ◽  
Marc JB Vreysen ◽  
Geoffrey Gimonneau ◽  
...  

Author(s):  
James Cronshaw

Long distance transport in plants takes place in phloem tissue which has characteristic cells, the sieve elements. At maturity these cells have sieve areas in their end walls with specialized perforations. They are associated with companion cells, parenchyma cells, and in some species, with transfer cells. The protoplast of the functioning sieve element contains a high concentration of sugar, and consequently a high hydrostatic pressure, which makes it extremely difficult to fix mature sieve elements for electron microscopical observation without the formation of surge artifacts. Despite many structural studies which have attempted to prevent surge artifacts, several features of mature sieve elements, such as the distribution of P-protein and the nature of the contents of the sieve area pores, remain controversial.


Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1689
Author(s):  
Tomasz Neumann

The subject of the article is a comparative long-distance transport analysis based on the relationship between central and eastern China and Poland. It provides an overview of issues related to long-haul China–Poland. The technique for order of preference by similarity to ideal solution (TOPSIS) method was proposed in the multi-criteria analysis. This method was briefly discussed, and its choice was justified. Then, the criteria adopted in the analysis were presented, i.e., time, cost, maximum number of containers, and ecology index. Multi-criteria analysis was carried out for three cases: the transport of one loading unit, 82 loading units, and 200 loading units. The geopolitical and operational situation on the transport route for the analyzed modes of transport was discussed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
T. Morel-Journel ◽  
E. Vergu ◽  
J.-B. Mercier ◽  
N. Bareille ◽  
P. Ezanno

AbstractThe transport of weaned calves from cow–calf producers to fatteners is a general concern for the young bull industry due to its documented negative impact on the welfare, health and performance of the animals. These transfers are often managed by intermediaries who transport weaned calves to sorting centres, where they are grouped into batches before being sent to fattening units. In this study, we present an algorithm to limiting these transfer distances by appropriately selecting the sorting centre through which they must go. We tested the effectiveness of this algorithm on historical data from a French beef producer organization managing 136,892 transfers using 13 sorting centres. The results show a decrease in the transfer distances compared to the historical record, especially for the calves travelling over long distances (− 76 km, i.e. 18% on average for the 33% longest transfers). Moreover, the distribution of calves between the sorting centres proposed by the algorithm reveals differences in their efficiency in minimizing transfer distances. In addition to its usefulness as a management tool for the daily transport of cattle, this algorithm provides prospects for improving the management of the sorting centres themselves.


2008 ◽  
Vol 45 (9) ◽  
pp. 1061-1082 ◽  
Author(s):  
Ryan C. McKellar ◽  
Alexander P. Wolfe ◽  
Ralf Tappert ◽  
Karlis Muehlenbachs

The Late Cretaceous Grassy Lake and Cedar Lake amber deposits of western Canada are among North America’s most famous amber-producing localities. Although it has been suggested for over a century that Cedar Lake amber from western Manitoba may be a secondary deposit having originated from strata in Alberta, this hypothesis has not been tested explicitly using geochemical fingerprinting coupled to comparative analyses of arthropod faunal content. Although there are many amber-containing horizons associated with Cretaceous coals throughout Alberta, most are thermally mature and brittle, thus lacking the resilience to survive long distance transport while preserving intact biotic inclusions. One of the few exceptions is the amber found in situ at Grassy Lake. We present a suite of new analyses from these and other Late Cretaceous ambers from western Canada, including stable isotopes (H and C), Fourier transform infrared (FTIR) spectra, and an updated faunal compendium for the Grassy and Cedar lakes arthropod assemblages. When combined with amber’s physical properties and stratigraphic constraints, the results of these analyses confirm that Cedar Lake amber is derived directly from the Grassy Lake amber deposit or an immediate correlative equivalent. This enables the palaeoenvironmental context of Grassy Lake amber to be extended to the Cedar Lake deposit, making possible a more inclusive survey of Cretaceous arthropod faunas.


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