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1.
Successful protected area networks must represent biodiversity across taxonomic groups. However, too often plant species are overlooked in conservation planning, and the resulting protected areas may, as a result, fail to encompass the most important sites for plant diversity. The Mozambique Tropical Important Plant Areas project sought to promote the conservation of Mozambique's flora through the identification of Important Plant Areas (IPAs). Here, we use the Weighted Endemism including Global Endangerment (WEGE) index to identify the richest areas for rare and endemic plants in Mozambique and subsequently evaluate how well represented these hotspots are within the current protected area and IPA networks. We also examine the congruence between IPA and protected areas to identify opportunities for strengthening the conservation of plants in Mozambique. We found that high WEGE scores, representing areas rich in endemic/near-endemic and threatened species, predict the presence of IPAs in Mozambique, but do not predict the presence of protected areas. We also find that there is limited overlap between IPAs and protected areas in Mozambique. We demonstrate how IPAs could be an important tool for ensuring priority sites for plant diversity are included within protected area network expansions, particularly following the adoption of the “30 by 30” target agreed within the post-2020 Convention on Biological Diversity framework, with great potential for this method to be replicated elsewhere in the global tropics.  相似文献   
2.
Plasmonics - Based on the influence of edge effect and channel shape, two new graphene nanoribbon field effect transistors are presented being useful in high-voltage and highly sensitive optical...  相似文献   
3.
Cancer results if regulatory mechanisms of cell birth and death are disrupted. Colorectal tumorigenesis is initiated by somatic or inherited mutations in the APC tumor suppressor gene pathway. Several additional genetic hits in other tumor suppressor genes and oncogenes drive the progression from polyps to malignant, invasive cancer. The majority of colorectal cancers present chromosomal instability, CIN, which is caused by mutations in genes that are required to maintain chromosomal stability. A major question in cancer genetics is whether CIN is an early event and thus a driving force of tumor progression. We present a new mathematical model of colon cancer initiation assuming a linear flow from stem cells to differentiated cells to apoptosis. We study the consequences of mutations in different cell types and calculate the conditions for CIN to precede APC inactivation. We find that early emergence of CIN is very likely in colorectal tumorigenesis.  相似文献   
4.
Animal artificial insemination (AI) suffers from bacterial contamination of semen media which results in decreased success of the process of artificial insemination. It is difficult to treat the semen extender medium to reduce the bacterial growth in the presence of semen using the conventional techniques of bacterial inhibition. In the present work, a new optical method developed for bacterial growth inhibition in semen containing extender medium using diode laser (DL) and commercial cheap light emitting diode (LED) is presented. Certain wavelengths and exposure times suitable for the process of artificial insemination are found to be optimum at reducing bacterial growth with a minimum significant effect on the semen motility and viability.  相似文献   
5.
Baylisascaris procyonis is a nematode of significant concern to public and domestic animal health as well as wildlife management. The population genetics of B. procyonis is poorly understood. To gain insights into patterns of genetic diversity within (infrapopulation level) and among (component population level) raccoon (Procyon lotor) hosts, and specifically to assess the relative importance of indirect and direct transmission of the parasite for explaining observed population structure, we collected 69 B. procyonis from 17 wild raccoons inhabiting five counties in Missouri and Arkansas, USA. Informative regions of mitochondrial (CO1, CO2) and nuclear (28S, ITS2) genes were amplified and the distribution and genetic variability of these genes were assessed within and across raccoons. Concatenation of the CO1 and CO2 mtDNA sequences resulted in 5 unique haplotypes, with haplotype diversity 0.456?±?0.068. The most common haplotype occurred in 94% of raccoons and 72.5% of B. procyonis. Sequences for 28S rDNA revealed four unique nuclear genotypes, the most common found in 100% of raccoons and 82.6% of B. procyonis. ITS2 genotypes were assessed using fragment analysis, and there was a 1:1 correspondence between 28S and ITS-2 genotypes. Infrapopulation variation in haplotypes and genotypes was high and virtually all hosts infected with multiple sequenced nematodes also harbored multiple haplotypes and genotypes. There was a positive relationship between the size of the analyzed infrapopulation (i.e., the number of nematodes analyzed) and the number of haplotypes identified in an individual. Collectively this work emphasizes the importance of indirect transmission in the lifecycle to this parasite.  相似文献   
6.
BackgroundIn Malaysia, dengue remains a top priority disease and usage of insecticides is the main method for dengue vector control. Limited baseline insecticide resistance data in dengue hotspots has prompted us to conduct this study. The present study reports the use of a map on the insecticide susceptibility status of Aedes aegypti and Aedes albopictus to provide a quick visualization and overview of the distribution of insecticide resistance.Method and resultsThe insecticide resistance status of Aedes populations collected from 24 dengue hotspot areas from the period of December 2018 until June 2019 was proactively monitored using the World Health Organization standard protocol for adult and larval susceptibility testing was conducted, together with elucidation of the mechanisms involved in observed resistance. For resistance monitoring, susceptibility to three adulticides (permethrin, deltamethrin, and malathion) was tested, as well as susceptibility to the larvicide, temephos. Data showed significant resistance to both deltamethrin and permethrin (pyrethroid insecticides), and to malathion (organophosphate insecticide) in all sampled Aedes aegypti populations, while variable resistance patterns were found in the sampled Aedes albopictus populations. Temephos resistance was observed when larvae were tested using the diagnostic dosage of 0.012mg/L but not at the operational dosage of 1mg/L for both species.ConclusionThe present study highlights evidence of a potential threat to the effectiveness of insecticides currently used in dengue vector control, and the urgent requirement for insecticide resistance management to be integrated into the National Dengue Control Program.  相似文献   
7.
Molecular Biology Reports - Epithelial-mesenchymal transition (EMT) is one of the mechanisms that contribute to bronchial remodelling which underlie chronic inflammatory airway diseases such as...  相似文献   
8.
Total Petroleum Hydrocarbons (TPH) are one of the most common groups of persistent environmental toxic organic contaminants to many organisms as well as to humans. In the present work, oil-polluted soil samples were phyto-remediated and analyzed. The investigated soil samples were collected from a location close to the oil petroleum production site in Ras-Gharib, Red Sea, Egypt. The phytoremediation process through TPH reduction and/or removal was carried out using Helianthus annuus (sunflower plant) based on its efficiency as a phytoremediator for organic pollutants. A preliminary four-week scheme of Helianthus annuus remediation, supported by twice quantized fertilization, provided a result of ~56% clean soil. Contaminated and phyto-remediated samples were diagnosed and analyzed through particle size distribution, Carbon-Hydrogen-Sulfur-Nitrogen elemental analysis (CHSN), Organic Matter content (OM%), Total Petroleum Hydrocarbons determination (%) and spectroscopically through Laser Induced Breakdown Spectroscopy (LIBS) and Laser Induced Fluorescence (LIF). Promising results have been achieved indicating the feasibility of planting sunflower for effective TPH remediation of the polluted soil and also the possibility of in situ monitoring of the remediation with easy, cost effective and fast spectrochemical analytical techniques, namely LIBS and LIF.  相似文献   
9.
Dung beetles feed mainly on scarce and ephemeral mammalian faeces making them vulnerable to declines of mammal populations. Therefore, studying how diverse groups like the Scarabaeinae subfamily utilize alternative food sources, such as decomposing invertebrates, enhances our understanding of their distribution and resilience in defaunated areas. One poorly studied aspect of the feeding habits of dung beetles is the potential differences between the sexes and their predatory behaviour. We evaluated how the sex (male and female) of individuals of Chalconotus convexus affected individual resource attraction to different bait types. Since C. convexus is known to feed on faeces, carrion and dead millipedes, we also test whether it can predate live individuals of millipedes. We used a combination of two field samplings and one laboratory experiment, using pitfall traps baited with faeces, carrion, millipedes and millipede's defensive compounds. While the preference for millipede was not associated with sex, we found a significant relationship between faeces and carrion, where females of C. convexus are significantly less attracted to faeces when compared to males and also males are significantly less attracted to carrion when compared to females. Furthermore, we also show that while actively consuming dead millipedes, C. convexus is unable to predate on live individuals. Our study illustrates that the versatility of food sources may help to explain the high abundance and wide distribution of C. convexus in Africa.  相似文献   
10.
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