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31.
Romina?P.?SuárezEmail author Maria?E.?Zaccagnini Kimberly?J.?Babbitt Noela?C.?Calamari Guillermo?S.?Natale Alexis?Cerezo Nadia?Codugnello Teresa?Boca Maria?J.?Damonte Josefina?Vera-Candioti Gregorio?I.?Gavier-Pizarro 《Landscape Ecology》2016,31(10):2485-2505
Context
Amphibians are declining worldwide and land use change to agriculture is recognized as a leading cause. Argentina is undergoing an agriculturalization process with rapid changes in landscape structure.Objectives
We evaluated anuran response to landscape composition and configuration in two landscapes of east-central Argentina with different degrees of agriculturalization. We identified sensitive species and evaluated landscape influence on communities and individual species at two spatial scales.Methods
We compared anuran richness, frequency of occurrence, and activity between landscapes using call surveys data from 120 sampling points from 2007 to 2009. We evaluated anuran responses to landscape structure variables estimated within 250 and 500-m radius buffers using canonical correspondence analysis and multimodel inference from a set of candidate models.Results
Anuran richness was lower in the landscape with greater level of agriculturalization with reduced amount of forest cover and stream length. This pattern was driven by the lower occurrence and calling activity of seven out of the sixteen recorded species. Four species responded positively to the amount of forest cover and stream habitat. Three species responded positively to forest cohesion and negatively to rural housing. Two responded negatively to crop area and diversity of cover classes.Conclusions
Anurans within agricultural landscapes of east-central Argentina are responding to landscape structure. Responses varied depending on species and study scale. Life-history traits contribute to responses differences. Our study offers a better understanding of landscape effects on anurans and can be used for land management in other areas experiencing a similar agriculturalization process.32.
Genotyping,pedigree reconstruction and endocrinological characterization of Acipenser naccarii (Bonaparte, 1836) using microsatellite markers and plasma steroid levels
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Ilaria Guarniero Laura Stancampiano Alessia Cariani Nadia Govoni Albamaria Parmeggiani Damiano Barboni Oliviero Mordenti 《Aquaculture Research》2017,48(11):5550-5560
This study aimed to set up a method for the long‐term management of Adriatic sturgeon, through the analysis of sex steroids and the genetic profiling of individuals in order to maximize the already reduced genetic variability of this species. Ten A. naccarii adults (nine of captive origin, one captured in the Ticino river and then moved into captivity) and eight subadults located in a semi‐natural land‐locked pond in Abbiategrasso (Milan, Italy) were analysed. Plasma testosterone differed significantly in the eight analysed subadults allowing their differentiation into two groups: the first group with an average testosterone concentration of 5.42 ± 1.31 ng/ml (probably female) and the second group with an average of 423.14 ± 75.97 ng/ml (probably male), as subsequently confirmed by artificial stripping. The plasma testosterone level was also significantly different between adult males and females (371.37 ± 43.58 vs. 95.34 ± 51.10 ng/ml), while the E2 levels showed no significant differences. Animals were genotyped on the basis of 10 microsatellite loci and their parental relationships were defined: four adults, two females and two males, generated the eight subadults. On the basis of pedigree analyses and genetic distances, 15 unrelated couples were identified for the future breeding seasons. Finally, the adult female captured in the Ticino River showed an interesting genetic profile, widely different from all of the other 17 specimens analysed, and represents a valuable source of genetic diversity. 相似文献
33.
Frank David Cdric Hubas Helne Laguerre Aicha Badou Gwen Herault Tho Bordelet Nadia Ameziane 《Aquaculture Nutrition》2020,26(5):1568-1583
Various research projects in Europe and North Africa have recently intended to breed temperate holothurians to alleviate fishing pressure on natural populations. However, to date little is known about the nutritional requirements of East Atlantic and Mediterranean species. In this study, we propose a “natural population”‐oriented approach to characterize food sources, digestive efficiency and resources allocation based on the composition of pigments and fatty acids (FA) in gut contents and tissues (muscles, gonads and digestive tract walls) of wild individuals of the species Holothuria (Panningothuria) forskali (Delle Chiaje, 1823) sampled in Brittany (France). Our study reveals that neither green nor red algae enter the diet of H. forskali in spring and that the only fresh vegetal material found in gut contents is brown algae (very likely diatoms). The high nutritional quality of gut contents however contrasts with the detrital nature of the ingested food sources, suggesting that a trophic upgrading of organic matter occurs before digestion. In addition, unusual FA (i.e. only present in a few groups of living species) such as long‐chain monounsaturated FA (especially the FA 23:1ω9) were found in large proportions in muscles and gonad and their effect on sea cucumber fitness needs further investigation. 相似文献
34.
Soybean seed coat chitinase as a defense protein against the stored product pest Callosobruchus maculatus
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35.
Noureen Arshad Khalid Mahmood Zia Farukh Jabeen Muhammad Naveed Anjum Nadia Akram Muhammad Kaleem Khosa 《Fibers and Polymers》2018,19(11):2219-2228
The research work was carried out to synthesize a series of novel chitosan based water dispersible polyurethanes (CS-WDPUs). The three step synthesis involves the formation of end capped PU-prepolymer was formed through the reaction between polyethylene glycol (PEG) (Mn=600 g/mole, dimethylolpropionic acid (DMPA) and isophorone diisocyanate (IPDI) followed by the preparation of neutralized NCO terminated PU-prepolymer, which lead to the chain extension by using the chitosan. The dispersion of the obtained product was carried out by adding proper proportion of water. The synthesized CS-WDPUs were applied onto the different qualities of plain weave poly-cotton printed and dyed textile swatches by employing pad-dry-cure procedures. The textile assets of the treated and untreated textile swatches were assessed, as color fastness, pilling resistance, tear and tensile strength. The results showed that the chitosan incorporation into PU backbone has significant effect on the assets of treated textiles. These synthesized CS-WDPUs are eco-friendly bio-based finishes with potential applications for polyester/cotton textiles. 相似文献
36.
Nicolas Marinval Pierre Saboural Oualid Haddad Murielle Maire Kevin Bassand Frederic Geinguenaud Nadia Djaker Khadija Ben Akrout Marc Lamy de la Chapelle Romain Robert Olivier Oudar Erwan Guyot Christelle Laguillier-Morizot Angela Sutton Cedric Chauvierre Frederic Chaubet Nathalie Charnaux Hanna Hlawaty 《Marine drugs》2016,14(10)
Herein we investigate the structure/function relationships of fucoidans from Ascophyllum nodosum to analyze their pro-angiogenic effect and cellular uptake in native and glycosaminoglycan-free (GAG-free) human endothelial cells (HUVECs). Fucoidans are marine sulfated polysaccharides, which act as glycosaminoglycans mimetics. We hypothesized that the size and sulfation rate of fucoidans influence their ability to induce pro-angiogenic processes independently of GAGs. We collected two fractions of fucoidans, Low and Medium Molecular Weight Fucoidan (LMWF and MMWF, respectively) by size exclusion chromatography and characterized their composition (sulfate, fucose and uronic acid) by colorimetric measurement and Raman and FT-IR spectroscopy. The high affinities of fractionated fucoidans to heparin binding proteins were confirmed by Surface Plasmon Resonance. We evidenced that LMWF has a higher pro-angiogenic (2D-angiogenesis on Matrigel) and pro-migratory (Boyden chamber) potential on HUVECs, compared to MMWF. Interestingly, in a GAG-free HUVECs model, LMWF kept a pro-angiogenic potential. Finally, to evaluate the association of LMWF-induced biological effects and its cellular uptake, we analyzed by confocal microscopy the GAGs involvement in the internalization of a fluorescent LMWF. The fluorescent LMWF was mainly internalized through HUVEC clathrin-dependent endocytosis in which GAGs were partially involved. In conclusion, a better characterization of the relationships between the fucoidan structure and its pro-angiogenic potential in GAG-free endothelial cells was required to identify an adapted fucoidan to enhance vascular repair in ischemia. 相似文献
37.
The expression pattern of TIR8 is conserved among vertebrates 总被引:1,自引:0,他引:1
Federica Riva Nadia Polentarutti Giulia Tribbioli Alberto Mantovani Cecilia Garlanda Lauretta Turin 《Veterinary immunology and immunopathology》2009,131(1-2):44-49
IL-1R/TLRs play an important role in the inflammatory responses. Their signaling pathway is tightly regulated to keep inflammation under control. The regulation involves both extracellular and intracellular mechanisms. TIR8, also known as SIGIRR (Single Immunoglobulin IL-1R-Related molecule), is an orphan receptor belonging to the IL-1R/TLRs super-family. Recent studies suggest its role in modulating the inflammatory response in the gastrointestinal tract in mice, acting as an IL-1 receptor family antagonist. We identified the sequence and analyzed the expression of TIR8 in a wide panel of organs and tissues in different animals. There was high homology of the cDNA sequence among human, mouse and the domestic species (74–85%). The pattern of expression of this receptor was similar in all the species examined (high levels in kidney and gastrointestinal tract) and similar to the human. These results demonstrate that TIR8 is conserved, in evolutionary terms, both with regard to sequence and pattern of expression, a finding consistent with a key function of this molecule in modulating inflammation in the gastrointestinal tract. 相似文献
38.
Ojeda-Robertos Nadia Florencia Torres-Chablé Oswaldo Margarito Peralta-Torres Jorge Alonso Luna-Palomera Carlos Aguilar-Cabrales Aguilar Chay-Canul Alfonso Juventino González-Garduño Roberto Machain-Williams Carlos Cámara-Sarmiento Ramón 《Tropical animal health and production》2017,49(3):613-618
Tropical Animal Health and Production - The objective was to determine the frequency of gastrointestinal parasites (GP) genera affecting water buffalo (Bubalus bubalis) reared under humid tropical... 相似文献
39.
Sathya K Chinnadurai Ryan DeVoe Amie Koenig Nadia Gadsen Amanda Ardente Stephen J Divers 《Veterinary anaesthesia and analgesia》2010,37(5):434-439
Objective The objective of this study was to compare an implanted direct blood pressure monitor and a non‐invasive oscillometric unit for use in anesthetized and awake green iguanas. Study design Prospective experimental trial. Animals Four male and four female adult green iguanas (Iguana iguana) weighing 1833 ± 534 g. Methods For each animal, the carotid artery was surgically exposed and the catheter tip of the pressure transducer was placed in the aortic arch. Non‐invasive blood pressure was measured using a cuff over the left femoral region. Pulse rate, respiratory rate and arterial blood pressure (ABP) measurements were taken every 5 minutes. Direct ABP measurements consisted of recording numerical values and graphic output. Simultaneous direct and indirect measurements were repeated in awake animals. Results The oscillometric device failed to provide a reading in over 80% of attempts, and failed to provide readings that correlated with direct measurements. The implanted direct transducer was capable of detecting blood pressures throughout all ABP ranges examined. Conclusions The implantable transducer was a reliable means of determining blood pressure in this study, while the oscillometric device was unreliable and often failed to provide any reading. Clinical relevance We do not recommend using the oscillometric device as described in a research or clinical setting for green iguanas. The advantages of an implantable device include the ability to monitor awake and anesthetized subjects remotely and continuously. These monitors are small, biocompatible and function across a wide range of ABP. 相似文献
40.
Khemais Abdellaoui Monia Ben Halima-Kamel Fatma Acheuk Noureddine Soltani Nadia Aribi Mohamed HabibBen Hamouda 《Pesticide biochemistry and physiology》2013
Experiments were conducted to assess the effect of gibberellic acid (GA3), a plant growth regulator, on Locusta migratoria migratoria fifth instar larvae. Newly emerged larvae were exposed to various concentrations of GA3 administered by topical application or by forced ingestion. Results showed that treated insects exhibited toxic symptoms with a dose-dependent mortality. GA3 toxicity was also demonstrated by perturbation of the moult processes. In fact, we noted that treated insects present exuviations difficulties due to the impossibility to reject the old integuments causing mortality in the 5th instar larvae. Histological study of proventriculus revealed alterations in the epithelial cells and absence of apolysis phenomenon. Data also showed that GA3 induced significant quantitative variation of haemolymph metabolites. These changes result in a significant decrease in the total concentration of proteins and carbohydrates and an increase in the total concentration of haemolymph lipids. 相似文献