In Winter Wheat (Triticum Aestivum L.), No-Till Improves Photosynthetic Nitrogen and Water-Use Efficiency     

Habbib  Hazzar  Hirel  Bertrand  Spicher  Fabien  Dubois  Frédéric  Tétu  Thierry 《Journal of Crop Science and Biotechnology》2020,23(1):39-46

Journal of Crop Science and Biotechnology - To evaluate the combined effect of different agricultural practices on photosynthetic nitrogen and water-use efficiency, winter wheat was grown in the...  相似文献   

Sexual dimorphism in limb long bones of the German Shepherd Dog     

Fabien Belhaoues  Sabine Breit  Gerhard Forstenpointner  Armelle Gardeisen 《Anatomia, histologia, embryologia》2020,49(4):464-477

The study of sexual dimorphism in dog anatomy, especially with regard to skeletal elements, has received little attention. The present work focuses on elements of the canine stylo- and zeugopodium, less documented than the skull or pelvis in the literature. In order to identify only sex-dependent effects, we analysed a single breed: the German Shepherd Dog. Data come from 25 dogs, with a balanced sex ratio (12 males and 13 females). Four skeletal elements of the forelimb and hindlimb (humerus, radius, femur, tibia) were each measured using seven linear morphometric variables. Univariate and multivariate analyses were then performed on these 28 variables. For all measurements, males are on average larger than females, with a mean sexual dimorphism ratio of 1.07. Sexual dimorphism is significant for 92.8% of the variables. Except of femoral measurements, diaphyseal values show the highest grade of sexual dimorphism. The mean level of disparity is higher in the forelimb (1.08) than in the hindlimb (1.05). A significant dimorphism is shown for the first component of principal component analyses conducted on each skeletal element, and for the second component with humerus measurements. Discriminant functions for sex identification give success rates included between 82% for the radius and 93% for the femur, the latter providing the highest reported score for sex identification in dogs from any skeletal element. These complementary statistic methods highlight a more dimorphic forelimb in size and a more dimorphic hindlimb in shape.  相似文献   

Experimental evolution of reduced sex ratio adjustment under local mate competition     

Macke E  Magalhães S  Bach F  Olivieri I 《Science (New York, N.Y.)》2011,334(6059):1127-1129

Theory predicts that local mate competition (LMC) favors the evolution of female-biased sex ratios. Empirical support of this prediction is indirect and comes from comparative studies or from studies showing that individuals can adjust their offspring sex ratio in response to varying LMC intensities. Replicate lines from a population of the spider mite Tetranychus urticae were selected under three LMC intensities for up to 54 generations. Within each selection regime, the final sex ratio matched theoretical predictions. Furthermore, the ability of individuals to adjust their offspring sex ratio diminished in females evolving under strict LMC, but not in females evolving under relaxed LMC levels. These results provide direct experimental evidence for the evolutionary process by which LMC modifies sex-allocation strategies and suggest that evolution under strict and constant LMC may lead to a loss of phenotypic plasticity.  相似文献   

Natural killer cell signaling pathways     

Vivier E  Nunès JA  Vély F 《Science (New York, N.Y.)》2004,306(5701):1517-1519

Natural killer (NK) cells are lymphocytes of the innate immune system that are involved in the early defenses against foreign cells, as well as autologous cells undergoing various forms of stress, such as microbial infection or tumor transformation. NK cell activation is controlled by a dynamic balance between complementary and antagonistic pathways that are initiated upon interaction with potential target cells. NK cells express an array of activating cell surface receptors that can trigger cytolytic programs, as well as cytokine or chemokine secretion. Some of these activating cell surface receptors initiate protein tyrosine kinase (PTK)-dependent pathways through noncovalent associations with transmembrane signaling adaptors that harbor intracytoplasmic ITAMs (immunoreceptor tyrosine-based activation motifs). Additional cell surface receptors that are not directly coupled to ITAMs also participate in NK cell activation. These include NKG2D, which is noncovalently associated to the DAP10 transmembrane signaling adaptor, as well as integrins and cytokine receptors. NK cells also express cell surface inhibitory receptors that antagonize activating pathways through protein tyrosine phosphatases (PTPs). These inhibitory cell surface receptors are characterized by intracytoplasmic ITIMs (immunoreceptor tyrosine-based inhibition motifs). The tyrosine-phosphorylation status of several signaling components that are substrates for both PTKs and PTPs is thus key to the propagation of the NK cell effector pathways. Understanding the integration of these multiple signals is central to the understanding and manipulation of NK cell effector signaling pathways.  相似文献   

Sensitivity to habitat fragmentation across European landscapes in three temperate forest herbs     

Naaf  Tobias  Feigs  Jannis Till  Huang  Siyu  Brunet  Jörg  Cousins  Sara A. O.  Decocq  Guillaume  De Frenne  Pieter  Diekmann  Martin  Govaert  Sanne  Hedwall  Per-Ola  Helsen  Kenny  Lenoir  Jonathan  Liira  Jaan  Meeussen  Camille  Plue  Jan  Poli  Pedro  Spicher  Fabien  Vangansbeke  Pieter  Vanneste  Thomas  Verheyen  Kris  Holzhauer  Stephanie I. J.  Kramp  Katja 《Landscape Ecology》2021,36(10):2831-2848

Landscape Ecology - Evidence for effects of habitat loss and fragmentation on the viability of temperate forest herb populations in agricultural landscapes is so far based on population genetic...  相似文献   

First chemical synthesis and in vitro characterization of the potential human metabolites 5-o-feruloylquinic acid 4'-sulfate and 4'-O-glucuronide     

Menozzi-Smarrito C  Wong CC  Meinl W  Glatt H  Fumeaux R  Munari C  Robert F  Williamson G  Barron D 《Journal of agricultural and food chemistry》2011,59(10):5671-5676

Feruloylquinic acids are a major class of biologically active phenolic antioxidants in coffee beans, but their metabolic fate is poorly understood. The present study investigated the phase II metabolism of feruloylquinic acids with selected human sulfotransferases (SULT1A1 and SULT1E1) and uridine 5'-diphosphoglucuronosyltransferases (UGT1A1 and UGT1A9). For unequivocal metabolite identification, the chemical synthesis of two potential human metabolites of 5-O-feruloylquinic acid, the 4'-sulfated and 4'-O-glucuronidated conjugates, has been performed for the first time. Following incubation with human SULT1A1 or SULT1E1, formation of 5-O-feruloylquinic acid 4'-O-sulfate was confirmed by matching its HPLC and MS data with those of the authentic standard. On the other hand, no glucuronide conjugates were detected after incubation with human uridine 5'-diphosphoglucuronosyltransferases. These results suggest that sulfation can take place on the ferulic acid moiety of feruloylquinic acids and may be a major metabolic pathway for feruloylquinic acids in humans.  相似文献   

A pmp genes-based PCR as a valuable tool for the diagnosis of avian chlamydiosis     

Laroucau K  Trichereau A  Vorimore F  Mahé AM 《Veterinary microbiology》2007,121(1-2):150-157

In a previous study we described the use of a new set of PCR primers (CpsiA/CpsiB) specific of the conserved pmp-family genes of Chlamydophila abortus as an efficient tool for the detection of these bacteria in ruminants including also preliminary results on avian strains. In this work, the use of this set of primers was extended to representative strains of the six major avian serovars (serovars A-F) and to field isolates of C. psittaci. For all the studied representative strains, using purified genomic DNA as a template, CpsiA/CpsiB primers allowed, as observed for C. abortus, a minimal 10-fold PCR signal increase compared to the one observed with ompA specific primers. In comparison to primers targeting the 16S-23S rRNA intergenic spacer, similar or increased sensitivity was observed depending on the strain. All the field isolates were amplified with CpsiA/CpsiB primers. On clinical samples, our primers are the best among those tested for detection of C. psittaci by simple conventional PCR. RFLP experiments performed using PCR fragments amplified with the CpsiA/CpsiB primers gave promising results demonstrating that these primers may provide an interesting tool for molecular typing when the bacterium cannot be grown from pathological samples.  相似文献   

Breeding for increased nitrogen‐use efficiency: a review for wheat (T. aestivum L.)          下载免费PDF全文

Fabien Cormier  John Foulkes  Bertrand Hirel  David Gouache  Yvan Moënne‐Loccoz  Jacques Le Gouis 《Plant Breeding》2016,135(3):255-278

Nitrogen fertilizer is the most used nutrient source in modern agriculture and represents significant environmental and production costs. In the meantime, the demand for grain increases and production per area has to increase as new cultivated areas are scarce. In this context, breeding for an efficient use of nitrogen became a major objective. In wheat, nitrogen is required to maintain a photosynthetically active canopy ensuring grain yield and to produce grain storage proteins that are generally needed to maintain a high end‐use quality. This review presents current knowledge of physiological, metabolic and genetic factors influencing nitrogen uptake and utilization in the context of different nitrogen management systems. This includes the role of root system and its interactions with microorganisms, nitrate assimilation and its relationship with photosynthesis as postanthesis remobilization and nitrogen partitioning. Regarding nitrogen‐use efficiency complexity, several physiological avenues for increasing it were discussed and their phenotyping methods were reviewed. Phenotypic and molecular breeding strategies were also reviewed and discussed regarding nitrogen regimes and genetic diversity.  相似文献   

An increase in the upper tree-limit of silver fir (Abiesalba Mill.) in the Alps since the mid-20th century: A land-use change phenomenon     

Sandrine Chauchard  Fabien Beilhe  Nicole Denis  Christopher Carcaillet 《Forest Ecology and Management》2010

Global environmental changes observed during recent decades are likely to have had an impact on the distribution of species. Currently, silver fir (Abies alba) is becoming established in the subalpine forests of the west central Alps at elevations higher than 2000 m a.s.l.; prior to the 1970s its upper altitudinal limit was 2000 m. Several hypotheses could explain this recent expansion of the upper tree-limit. Silver fir regeneration could be linked (1) to land-use changes or (2) to current climatic warming. Using dendrochronology, the age structure of 31 forest plots containing at least one silver fir was examined in order to elucidate the population dynamics of subalpine communities. This allowed us to decipher the timing of fir regeneration in relation to the mean age of the stands examined and of the other tree-canopy species present. The majority of the firs germinated sporadically since 1950, before the regional temperature increase. The pattern of fir recruitment did not appear to relate to altitude, but followed a pattern characteristic of secondary succession. The age structures identified showed an exponential increase in tree-density during the 20th century; the stands were first dominated by Larix decidua during the 18th and 19th centuries, and then by Pinus cembra during the 20th century. In most stands, fir regeneration occurred after Larix and before P. cembra dominated, following a similar pattern to Picea abies regeneration. The number of local inhabitants and temperature both exhibited a negative relationship with fir tree recruitment, thus supporting the land-use change hypothesis. There has been a significant upward shift of the altitudinal range of fir, amounting to an increase of about 300 m since 1950. This followed the abandonment of low-productivity land. This trend is likely to continue during the 21st century, because of new agricultural and forestry practices which involve limited intervention in low-productivity areas and may be because of the effects of global warming.  相似文献   

Post‐capture survival of whale sharks encircled in tuna purse‐seine nets: tagging and safe release methods          下载免费PDF全文

Lauriane Escalle  Hilario Murua  Justin Monin Amande  Igor Arregui  Pierre Chavance  Alicia Delgado de Molina  Daniel Gaertner  Igaratza Fraile  John David Filmalter  Josu Santiago  Fabien Forget  Haritz Arrizabalaga  Laurent Dagorn  Bastien Merigot 《水产资源保护:海洋与淡水生态系统》2016,26(4):782-789

1. Whale shark, the world's largest fish, is believed to be particularly vulnerable owing to its biological characteristics (slow growth, late maturation, great longevity) and is listed as Vulnerable by IUCN and included in Appendix II of CITES. 2. Whale sharks are occasionally encircled in tropical tuna purse‐seine nets, throughout this global fishery. Although apparent immediate survival rates following encirclement and release have recently been assessed through scientific onboard observer programmes, a more rigorous methodology is still required for studying post‐released survival. 3. This work provides a method for applying pop‐up satellite tags and reports an enhanced release procedure for whale sharks. The first assessment of survival after release from purse‐seine nets involved six whale sharks tagged between May and September 2014 in the eastern tropical Atlantic Ocean. Five tags transmitted data: three popped up as programmed (after 30 days), while two surfaced prematurely (one after 21 and the other after 71 days (programmed to pop off after 30 and 90 days, respectively)) but showed no sign of unusual behaviour. 4. Overall, whale sharks survived at least 21 days (one at least 71 days) after release from purse‐seine nets. These observations based on five large individuals (total length > 8 m), suggest that whale sharks have a good chance of survival when released with the proposed method. 5. Additional tagging in this and other oceans, especially of juveniles which may be more sensitive to encirclement and release operations, is essential to further assess whale shark post‐release survival rates in tuna purse‐seine fisheries. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献