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951.
Tristam Barrett Giuseppe Feola Marina Khusnitdinova Viktoria Krylova 《Human ecology: an interdisciplinary journal》2017,45(6):747-762
The convergence of climate change and post-Soviet socio-economic and institutional transformations has been underexplored so far, as have the consequences of such convergence on crop agriculture in Central Asia. This paper provides a place-based analysis of constraints and opportunities for adaptation to climate change, with a specific focus on water use, in two districts in southeast Kazakhstan. Data were collected by 2 multi-stakeholder participatory workshops, 21 semi-structured in-depth interviews, and secondary statistical data. The present-day agricultural system is characterised by enduring Soviet-era management structures, but without state inputs that previously sustained agricultural productivity. Low margins of profitability on many privatised farms mean that attempts to implement integrated water management have produced water users associations unable to maintain and upgrade a deteriorating irrigation infrastructure. Although actors engage in tactical adaptation measures, necessary structural adaptation of the irrigation system remains difficult without significant public or private investments. Market-based water management models have been translated ambiguously to this region, which fails to encourage efficient water use and hinders adaptation to water stress. In addition, a mutual interdependence of informal networks and formal institutions characterises both state governance and everyday life in Kazakhstan. Such interdependence simultaneously facilitates operational and tactical adaptation, but hinders structural adaptation, as informal networks exist as a parallel system that achieves substantive outcomes while perpetuating the inertia and incapacity of the state bureaucracy. This article has relevance for critical understanding of integrated water management in practice and adaptation to climate change in post-Soviet institutional settings more broadly. 相似文献
952.
Histone H4K20 tri‐methylation at late‐firing origins ensures timely heterochromatin replication 下载免费PDF全文
Charlotte Grimaud Paulina Prorok Christelle Cayrou Gunnar Schotta Alhassan F Abdelsamie Jérôme Déjardin Marcel Méchali Giuseppe Baldacci Claude Sardet Jean‐Charles Cadoret Aloys Schepers Eric Julien 《The EMBO journal》2017,36(18):2726-2741
Among other targets, the protein lysine methyltransferase PR‐Set7 induces histone H4 lysine 20 monomethylation (H4K20me1), which is the substrate for further methylation by the Suv4‐20h methyltransferase. Although these enzymes have been implicated in control of replication origins, the specific contribution of H4K20 methylation to DNA replication remains unclear. Here, we show that H4K20 mutation in mammalian cells, unlike in Drosophila, partially impairs S‐phase progression and protects from DNA re‐replication induced by stabilization of PR‐Set7. Using Epstein–Barr virus‐derived episomes, we further demonstrate that conversion of H4K20me1 to higher H4K20me2/3 states by Suv4‐20h is not sufficient to define an efficient origin per se, but rather serves as an enhancer for MCM2‐7 helicase loading and replication activation at defined origins. Consistent with this, we find that Suv4‐20h‐mediated H4K20 tri‐methylation (H4K20me3) is required to sustain the licensing and activity of a subset of ORCA/LRWD1‐associated origins, which ensure proper replication timing of late‐replicating heterochromatin domains. Altogether, these results reveal Suv4‐20h‐mediated H4K20 tri‐methylation as a critical determinant in the selection of active replication initiation sites in heterochromatin regions of mammalian genomes. 相似文献
953.
Maribel Dolande Nataly García Ana María Capote María Mercedes Panizo Giuseppe Ferrara Víctor Alarcón 《Current fungal infection reports》2017,11(4):197-202
Purpose of Review
The purpose of this review is to contribute to the knowledge about the existence of Candida auris as an emerging pathogenic fungus, multi-resistant to antifungal, and causing health care-associated infections (HCAI).Recent Findings
C. auris emerges as yeast with clonal transmission resistance to three families of commonly used antifungals, mainly azoles (fluconazole and voriconazole), diminishing therapeutic options for the treatment of fungal infections. In 2009, C. auris was isolated for the first time in Japan and by the time of this review, it has been reported in different countries in Africa, America, Asia, and Europe.Summary
It is important to identify yeasts of the Candida genus up to species, to perform susceptibility tests and to implement surveillance, prevention, and control measures, to minimize the global spread of this fungus, due to its impact on public health.954.
Floral-colour polymorphism in rewardless orchids has been hypothesized to be maintained by means of naïve insects, which after visiting a flower without reward will tend to fly elsewhere, looking for a flower of a different colour. In this study, levels of male and female reproductive success were monitored in Southern Italy populations of the deceptive orchid Dactylorhiza sambucina, through field observations over 3 years. These populations were characterized by the presence of a rare pink morph which is sympatric with the more frequent yellow and red morphs. In addition, final plant fertility was evaluated through percentages of embryo-containing seeds produced in both natural conditions and hand-pollination experiments. Results showed that pollinator preferences were independent of the morph frequencies and thus do not promote the predicted negative frequency-dependent selection. Although yellow and pink morphs showed significantly higher male reproductive success (RS), we found comparable levels of female RS, which suggest that pollinator behaviour cannot be the main mechanism which maintains this polymorphism. Interestingly, we found different percentages of embryo-containing seeds in fruits set under natural conditions as well as in those obtained from experimental crosses. In particular, pink morph showed a very low intrinsic fertility. Moreover, fertility in intra- was higher than in inter-morph crosses. To our knowledge, this is the first study pointing out the occurrence in the orchid family of post-pollination reproductive barriers. Findings are discussed in light of present hypothesis on the evolution and maintenance of colour polymorphism in deceptive orchids and other angiosperms. 相似文献
955.
Castagna C Abt G Manzi V Annino G Padua E D'Ottavio S 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(3):923-929
The aim of this study was to examine the effect of recovery mode on repeated sprint ability in young basketball players. Sixteen basketball players (age, 16.8 +/- 1.2 years; height, 181.3 +/- 5.7 cm; body mass, 73 +/- 10 kg; VO2max, 59.5 +/- 7.9 mL x kg(-1) x min(-1)) performed in random order over 2 separate occasions 2 repeated sprint ability protocols consisting of 10 x 30-m shuttle run sprints with 30 seconds of passive or active (running at 50% of maximal aerobic speed) recovery. Results showed that fatigue index (FI) during the active protocol was significantly greater than in the passive condition (5.05 +/- 2.4, and 3.39 +/- 2.3, respectively, p < 0.001). No significant association was found between VO2peak and FI and sprint total time (TT) in either repeated sprint protocols. Blood lactate concentration at 3 minutes post exercise was not significantly different between the 2 recovery conditions. The results of this study show that during repeated sprinting, passive recovery enabled better performance, reducing fatigue. Consequently, the use of passive recovery is advisable during competition in order to limit fatigue as a consequence of repeated high intensity exercise. 相似文献
956.
Salvatore de Maria Vittoria Metafora Salvatore Metafora Gianpietro Ravagnan Maria Cartení Gabriele Pontoni Angelo Facchiano Marilena Lepretti Beatrice Severino Giuseppe Caliendo Vincenzo Santagada Ingrid Langer Patrick Robberecht 《Journal of peptide science》2008,14(1):102-109
Increase of VPAC receptor s binding to the (16)gamma-glutamyl diaminopropane vasoactive intestinal peptide (VIP-DAP) agonist, a vasoactive intestinal polypeptide (VIP) structural analogue containing a positive charge at position 16, has confirmed the importance of a positive charge at this site. By investigating the effect of distance from the peptide backbone Calpha of a positive charge in position 16, data are reported here concerning: (i) a novel chemical method used for the synthesis of a new family of (16)gamma-glutamyl diamine VIP derivatives differing among them for single carbon atoms and including diaminoethane (VIP-DAE2), diaminopropane (VIP-DAP3), diaminobutane (VIP-DAB4), diaminopentane (VIP-DAP5), and diaminohexane (VIP-DAH6); (ii) functional characterization of these compounds on human VPAC1 and VPAC2 receptors. In more detail, the EC50 and IC50 values, when measured as a function of the alkylic chain length, show in more detail, that the use of VIP-DAB4 derivative changes the IC50 but not the EC50, thus indicating on hVPAC2 receptor an unexpected relationship between binding and activity that differs from that obtained on hVPAC1. 相似文献
957.
Non-organ-specific autoantibodies in renal transplant recipients: relation to BK virus infection 总被引:1,自引:0,他引:1
Costa C Touscoz GA Bergallo M Sidoti F Terlizzi ME Astegiano S Merlino C Segoloni GP Cavallo R 《The new microbiologica》2008,31(2):175-180
Polyomavirus BK reactivation is common in renal transplant recipients and may cause nephropathy with significant graft dysfunction. The induction of anti-double stranded DNA (anti-dsDNA) antibodies by BKV has been described in experimental animals and during primary infection, and has been implicated in the pathogenesis of systemic lupus erythematosus. This study evaluated the occurrence of anti-dsDNA antibodies and non-organ-specific autoantibodies (NOSA) by indirect immunofluorescence before transplantation and at 3 and 6 months post-transplantation in 90 renal transplant recipients and the association with BKV reactivation, demographic and clinical features. Moreover, the relation to HCMV infection, as detected by pp65-antigenemia, was also evaluated. Post-transplantation NOSAs were present in 23/90 (25.6%) and anti-dsDNA antibodies in 17/90 (18.9%). BK viremia was detected in at least one serum sample in 22 patients: 9 anti-dsDNA antibody-positive vs 13 negative (p<0.01). No significant correlation between the occurrence of NOSAs and anti-dsDNA antibodies and demographic and clinical features was found. No significant association with pp65-antigenemia-positivity was found, although antigenemia was positive in 6/23 NOSA-positive patients (26.1%). Although a relation seems to exist between BKV and the occurrence of anti-dsDNA antibodies in renal transplant patients, the lack of correlation with other epidemiological and clinical features does not allow any conclusion. The role of autoimmune response in this context and the relation with other patient-related factors and infectious agents should be further investigated. 相似文献
958.
Laura Toppino Giampiero Valè Giuseppe Leonardo Rotino 《Molecular breeding : new strategies in plant improvement》2008,22(2):237-250
The two eggplant relatives Solanum aethiopicum gr. Gilo and Solanum aethiopicum gr. Aculeatum (=Solanum integrifolium) carry resistance to the fungal wilt disease caused by Fusarium oxysporum f. sp. melongenae, a worldwide soil-borne disease of eggplant. To introgress the resistance trait into cultivated eggplant, the tetraploid
somatic hybrids S. melongena + S. aethiopicum and S. melongena + S.
integrifolium were used. An inheritance study of the resistance was performed on advanced anther culture-derived androgenetic backcross
progenies from the two somatic hybrids. The segregation fitted a 3 resistant (R): 1 susceptible (S) ratio in the selfed populations
and a 1R:1S ratio in the backcross progenies for the trait derived from S. aethiopicum and S. integrifolium. These ratios are consistent with a single gene, which we designated as Rfo-sa1, controlling the resistance to Fusarium oxysporum f. sp. melongenae. The allelic relationship between the resistance genes from S. aethiopicum and S. integrifolium indicate that these two genes are alleles of the same locus. Bulked Segregant Analysis (BSA) was performed with RAPD markers
on the BC3/BC5 resistant advanced backcross progenies, and three RAPD markers associated with the resistance trait were identified. Cleaved
Amplified Polymorphic Sequences (CAPSs) were subsequently obtained on the basis of the amplicon sequences. The evaluation
of the efficiency of these markers in predicting the resistant phenotype in segregating progenies revealed that they represent
useful tools for indirect selection of Fusarium resistance in eggplant. 相似文献
959.
Consistent performance of invasive plant species within and among islands of the Mediterranean basin
Anna Traveset Giuseppe Brundu Luisa Carta Irene Mprezetou Philip Lambdon Manuela Manca Frédéric Médail Eva Moragues Javier Rodríguez-Pérez Akis-Stavros D. Siamantziouras Carey M. Suehs Andreas Y. Troumbis Montserrat Vilà Philip E. Hulme 《Biological invasions》2008,10(6):847-858
Since the success of an invasive species depends not only upon its intrinsic traits but also on particular characteristics
of the recipient habitat, assessing the performance of an invader across habitats provides a more realistic analysis of risk.
Such an analysis will not only provide insights into the traits related to invasiveness, but also the habitat characteristics
that underpin vulnerability to invasion that, taken together, will facilitate the selection of management strategies to mitigate
the invader’s effect. In the present study, we considered the Mediterranean basin islands as an excellent study region to
test how the same invasive species perform in different habitats within a single island, and to scale up differences among
islands with similar climate. We tested how the performance of three widespread plant invaders with clonal growth but contrasting
life-history traits, a deciduous tree Ailanthus altissima, a succulent subshrub Carpobrotus spp., and an annual geophyte Oxalis pes-caprae, varied depending upon the species identity, habitat, and invaded island. The environmental parameters considered were habitat
type, elevation, species diversity in the invaded plot, and several soil traits (% C, % N, C/N, pH, and relative humidity).
The study documents that the performance of these three important and widespread plant invaders is dependent mainly on species
identity, and less upon the invaded island’s general features. Likewise, differences in performance among habitats were only
significant in the case of Ailanthus, whereas Carpobrotus and Oxalis appear to perform equally well in different environments. Ailanthus thus appears to have a broader spectrum of invasiveness, being able to invade a larger number of habitat types. On the contrary,
Carpobrotus spp. have not yet invaded habitats different from those where the species have been originally introduced and where they
are still commonly spread by humans. Oxalis distribution is mainly related to agricultural activities and disturbed sites, and the total area infested by this geophyte
may be more reflection of the extent of suitable habitats than of invasiveness or ecological impact. Our results confirm the
potential for these species to significantly alter the functioning of ecosystems in the Mediterranean islands and highlight
the risk to other islands not yet invaded. 相似文献
960.
Melania D'Orazio Raffaella Scotti Laura Nicolini Laura Cervoni Giuseppe Rotilio Andrea Battistoni Roberta Gabbianelli 《BMC microbiology》2008,8(1):166