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1.
Inorg Chem ; 62(5): 1885-1890, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35639728

RESUMO

The impact of 4f metal ions Ln3+ (Ln = La or Ce) versus 5f metal ions Un+ (n = 3 or 4) on the compositions and distribution of 5p metal atoms in the cluster shells of endohedral species [M@Sn14-xSbx]q- (M = La, Ce, or U; x = 6-8; q = 3, 4) was studied by means of combined experimental and quantum chemical investigations. While all known f-block metal ion-centered endohedral clusters possessed combinations of larger main group metal atoms so far (Sn/Bi or Pb/Bi), resulting in mixtures of 13- and 14-atom cages, the 14-atom cages reported herein comprise exclusively Sn and Sb atoms and therefore are challenged in accommodating the large 4f and 5f ions. We show that the clusters form in reactions of (Sn2Sb2)2- anions with [Ln(C5Me4H)3] or [U(C5Me4H)3Cl], and that salts of [La@Sn6Sb8]3-, [La@Sn7Sb7]4-, [U@Sn8Sb6]4-, and [U@Sn7Sb7]3- can be isolated from them. The assignment of Sn versus Sb in the encapsulating cage follows a simple rule. Different central atoms cause only slight differences in this regard and with respect to distortions of the cluster shells. The reactions also yielded the salt of the new binary anion (Sn4Sb4)2- that was recently predicted by quantum chemical studies.

2.
Oecologia ; 202(4): 641-653, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37543993

RESUMO

The hazel dormouse is predominantly an arboreal species that moves down to the ground to hibernate in the autumn in temperate parts of its distributional ranges at locations not yet well understood. The main objective of this study is to test whether environmental characteristics surrounding hazel dormouse hibernacula can be identified using high-resolution remote sensing and data collected in situ. To achieve this, remotely sensed variables, including canopy height and cover, topographic slope, sky view, solar radiation and cold air drainage, were modelled around 83 dormouse hibernacula in England (n = 62) and the Netherlands (n = 21), and environmental characteristics that may be favoured by pre-hibernating dormice were identified. Data on leaf litter depth, temperature, canopy cover and distance to the nearest tree were collected in situ and analysed at hibernaculum locations in England. The findings indicated that remotely sensed data were effective in identifying attributes surrounding the locations of dormouse hibernacula and when compared to in situ information, provided more conclusive results. This study suggests that remotely sensed topographic slope, canopy height and sky view have an influence on hazel dormice choosing suitable locations to hibernate; whilst in situ data suggested that average daily mean temperature at the hibernaculum may also have an effect. Remote sensing proved capable of identifying localised environmental characteristics in the wider landscape that may be important for hibernating dormice. This study proposes that this method can provide a novel progression from habitat modelling to conservation management for the hazel dormouse, as well as other species using habitats where topography and vegetation structure influence fine-resolution favourability.


Assuntos
Myoxidae , Animais , Ecossistema , Árvores , Temperatura , Inglaterra
3.
Instr Course Lect ; 72: 125-138, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36534852

RESUMO

Benign soft-tissue masses drastically outnumber malignant tumors. Both benign and malignant soft-tissue masses can present in the same manner, as a painless growing soft-tissue lump or bump. The implications of misdiagnosing a soft-tissue sarcoma can be devastating. The most common mistake occurs when all masses are assumed to be lipomas. A careful history, physical examination, and appropriate imaging can determine the benign or malignant nature of a tumor. A mass that is large (>5 cm), deep (in relation to investing fascia), and firmer than the surrounding muscle should raise suspicion for a malignancy. Small, superficial masses are more likely to be benign, but up to 32% of soft-tissue sarcomas can present in this manner. The orthopaedic surgeon should be able to recognize common imaging findings for benign and malignant entities.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Humanos , Neoplasias de Tecidos Moles/cirurgia , Fáscia/patologia , Imageamento por Ressonância Magnética/métodos , Diagnóstico Diferencial
4.
Angew Chem Int Ed Engl ; 61(41): e202207232, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35833677

RESUMO

The solid mixture "K2 GeSb" was shown to comprise single-crystalline K12 Ge3.5 Sb6 (1), a double salt of K5 [GeSb3 ] with carbonate-like [GeSb3 ]5- anions, and the metallic Zintl phase K2 Ge1.5 . Extraction of 1 with ethane-1,2-diamine in the presence of crypt-222 afforded [K(crypt-222)]+ salts of several novel binary Zintl anions: (Ge2 Sb2 )2- (in 2), (Ge4 Sb12 )4- (in 3), and in the presence of [AuMePPh3 ] also (Ge4 Sb14 )4- (in 4). The anion in 2 represents a predicted, yet heretofore missing pseudo-tetrahedral anion. 4 comprises a cluster analogous to (Ge4 Bi14 )4- and (Ga2 Bi16 )4- , and thus one of the most Sb-rich binary p-block anions. The unprecedented cluster topology in 3 can be viewed as a defect-version of the one in 4 upon following a "dead end" of cluster growth. The findings indicate that Ge and Sb atoms are at the border of a well-matching and a mismatch elemental combination. We discuss the syntheses, the geometric structures, and the electronic structures of the new compounds.

5.
J Natl Compr Canc Netw ; 19(3): 295-306, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33556919

RESUMO

BACKGROUND: Practice patterns of radiation therapy (RT) use for soft-tissue sarcoma (STS) remain quite variable, despite clinical practice guidelines recommending the addition of RT to surgery for patients with high-grade STS, particularly for larger tumors. Using the National Cancer Database (NCDB), we assessed patterns of overall RT use, neoadjuvant versus adjuvant treatment, and specific RT modalities in this population. PATIENTS AND METHODS: Patients aged ≥18 years with stage II/III STS in 2004 through 2015 were identified from the NCDB. Patterns of care were assessed using multivariable logistic regression analysis. RESULTS: Of 27,426 total patients, 11,654 (42%) were treated with surgery alone versus 15,772 (58%) with RT in addition to surgery, with no overall increase in RT use over the study period. Notable clinical predictors of receipt of RT included tumor size (>5 cm), grade III, and tumors arising in the extremities. Conversely, female sex, older age (≥70 years), Black race, noncommercial insurance coverage, farther distance to treatment, and poor performance status were negative predictors of RT use. Of those receiving RT, 27% were treated with neoadjuvant RT and 73% with adjuvant RT. The proportion of those receiving neoadjuvant RT increased over time. Relevant factors associated with neoadjuvant RT included treatment at academic centers, larger tumor size, and extremity tumors. Of those who received RT with a modality specified as either intensity-modulated RT (IMRT) or 3D conformal RT (3DCRT), 61% were treated with IMRT and 39% with 3DCRT. The proportion of patients treated with IMRT increased over time. Relevant factors associated with IMRT use included treatment at academic centers, commercial insurance coverage, and larger and nonextremity tumors. CONCLUSIONS: Although use of neoadjuvant RT and IMRT has increased over time, a significant number of patients with STS are not receiving adjuvant or neoadjuvant RT. Our findings also note potential sociodemographic disparities and highlight the concern that not all patients with STS are being equally considered for RT.

6.
J Anim Ecol ; 90(1): 248-259, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32961581

RESUMO

Phenological change is the most widely documented biological impact of climate change, but shows marked variation in magnitude among populations and species. Thus, quantifying the environmental factors and organismal differences driving this intra- and interspecific variability in phenology is vital to understand and forecast the ecological consequences of climate change. Here, we test intra- and interspecific differences for a set of butterfly species in the organismal sensitivity of flight phenology and its dependence on environmental factors, using as our model system an elevation gradient in a Mediterranean mountain range where temperature and relative humidity vary substantially over space and time. We use field-collected meteorological data, and butterfly counts for 20 univoltine species over 14 years, to test the relative effects on phenology of temperature and relative humidity, the sensitivity of phenology to spatial and temporal variation in temperature and whether ecological traits account for inter-specific variation in sensitivity. For all species, temperature in the months immediately preceding adult emergence had the strongest relationship with phenology. All species appeared earlier in warmer years, with those flying earlier in the season showing the greatest sensitivity to annual (temporal) variation in temperature. However, only a minority of species showed evidence of plastic, space-for-time responses to temperature. Instead, most species showed strong evidence that phenology was more sensitive to temporal than spatial variation in temperature. Our results support the dominant influence of temperature on phenology, even in Mediterranean environments suffering summer drought. They also suggest that accurate forecasts of species' phenological shifts could require the isolation of spatial from temporal components of temperature variation, because the sensitivity of populations and species may differ across these two dimensions. The factors driving synchronisation of phenology over space merit particular research in the context of climate change, given their potential to expose populations simultaneously to environmental extremes.


Assuntos
Borboletas , Mudança Climática , Animais , Fenótipo , Estações do Ano , Temperatura
7.
Biol Lett ; 17(8): 20210175, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34343435

RESUMO

The consequences of climate change for biogeographic range dynamics depend on the spatial scales at which climate influences focal species directly and indirectly via biotic interactions. An overlooked question concerns the extent to which microclimates modify specialist biotic interactions, with emergent properties for communities and range dynamics. Here, we use an in-field experiment to assess egg-laying behaviour of a range-expanding herbivore across a range of natural microclimatic conditions. We show that variation in microclimate, resource condition and individual fecundity can generate differences in egg-laying rates of almost two orders of magnitude in an exemplar species, the brown argus butterfly (Aricia agestis). This within-site variation in fecundity dwarfs variation resulting from differences in average ambient temperatures among populations. Although higher temperatures did not reduce female selection for host plants in good condition, the thermal sensitivities of egg-laying behaviours have the potential to accelerate climate-driven range expansion by increasing egg-laying encounters with novel hosts in increasingly suitable microclimates. Understanding the sensitivity of specialist biotic interactions to microclimatic variation is, therefore, critical to predict the outcomes of climate change across species' geographical ranges, and the resilience of ecological communities.


Assuntos
Borboletas , Microclima , Animais , Mudança Climática , Ecossistema , Feminino , Herbivoria , Plantas , Temperatura
8.
Chem Rev ; 119(14): 8506-8554, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31136158

RESUMO

Clusters have been the subject of intense investigations since their famous definition launched by Cotton in 1963, and the area has expanded ever since. One obvious development addresses the widening of the definition of what to call a cluster: from purely (transition) metal-metal linked assemblies, as per Cotton's early denomination, to nonmetal/metal clusters or purely nonmetal cages, like fullerenes, and even noncovalent aggregates such as water clusters. The other extension concerns the broadened spectrum of compositions within the aforementioned cluster types and their corresponding structures that range from trinuclear motifs to clusters with sizes in the range of the hemoglobin unit. This review article reports on one cluster family that has its origins in traditional Zintl anion chemistry but has undergone rapid development in recent years, namely, ligand-free clusters that combine main group and transition metal atoms. Depending on the position of the transition metal atom(s), one refers to such clusters as intermetalloid (endohedral) clusters or as a special type of heterometallic clusters. The predominant synthetic access makes use of soluble Zintl anions. Other pathways for their preparation include traditional solid state reactions of according element combinations or bottom-up syntheses employing low valent organo-main group element sources. This survey will shed light on all of these approaches, with an emphasis on the syntheses that employ soluble Zintl anion compounds. The article will give a comprehensive overview of the currently known compounds, their different synthesis protocols, and analytic techniques for determination of their compositions, structures, and further properties. Additionally, this survey will report peculiarities of bonding situations found within some of the cluster molecules, which were studied by means of sophisticated quantum chemical investigations.

9.
Adv Exp Med Biol ; 1257: 13-29, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32483727

RESUMO

Advances in chemotherapy, sophisticated imaging, and surgical techniques over the last few decades have allowed limb-salvage surgery (LSS) to become the preferred surgical treatment for bone sarcomas of the extremities. The goal of LLS is to maximize limb functionality to allow for the maintenance of quality of life without compromising overall survival and tumor local recurrence rates. Today, limb-salvage procedures are performed on 80-95% of patients with extremity osteosarcoma, and the 5-year survival rate in extremity osteosarcoma patients is now 60-75%.This chapter will focus on LSS for extremity osteosarcoma. Common types of surgical reconstruction techniques including endoprostheses, intercalary or osteoarticular allografts, vascularized fibular autografts, and allograft prosthetic composites (APC), and their complications such as infection, local recurrence, graft fracture, implant failure, and nonunion will be discussed in detail. Anatomic locations of lesions discussed include the proximal femur, distal femur, proximal tibia, distal tibia, proximal humerus, distal humerus, and forearm bones.


Assuntos
Neoplasias Ósseas , Salvamento de Membro , Osteossarcoma , Neoplasias Ósseas/cirurgia , Transplante Ósseo , Humanos , Recidiva Local de Neoplasia , Osteossarcoma/cirurgia , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento
10.
Angew Chem Int Ed Engl ; 59(34): 14251-14255, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32449980

RESUMO

The pseudo-element concept, in its most general formulation, states that isoelectronic atoms form equal numbers of bonds. Hence, clusters such as Zintl ions usually retain their structure upon isoelectronic replacement of some or all atoms. Here, a deviation from this common observation is presented, namely the formation of (Sn5 Sb3 )3- (1), a rare example of an eight-vertex Zintl ion, and an unprecedented example of a Zintl ion synthesized by solution means that has an arachno-type structure according to the Wade-Mingos rules. Three structure-types of interest for (Sn5 Sb3 )3- were identified by DFT calculations: one that matched the X-ray diffraction data, and two that that were reminiscent of fragments of known clusters. A study on the isoelectronic series of clusters, (Snx Sb8-x )2-x (x=0-8), showed that the relative energies of these three isomers vary significantly with composition (independent of electron count) and that each is the global minimum at least once within the series.

11.
Ecol Appl ; 29(8): e01989, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31376197

RESUMO

Species-focused conservation planning is often based on reducing local extinction risk at key sites. However, with increasing levels of habitat fragmentation and pressures from climate change and overexploitation, surrounding landscapes also influence the persistence of species populations, and their effects are increasingly incorporated in conservation planning and management for both species and communities. Here, we present a framework based on metapopulation dynamics in fragmented landscapes, for quantifying the survival (resistance) and reestablishment of species populations following localized extinction events (resilience). We explore the application of this framework to guide the conservation of a group of threatened bird species endemic to papyrus (Cyperus papyrus) swamps in East and Central Africa. Using occupancy data for five species collected over two years from a network of wetlands in Uganda, we determine the local and landscape factors that influence local extinction and colonization, and map expected rates of population turnover across the network to draw inferences about the locations that contribute most to regional resistance and resilience for all species combined. Slight variation in the factors driving extinction and colonization between individual papyrus birds led to species-specific differences in the spatial patterns of site-level resistance and resilience. However, despite this, locations with the highest resistance and/or resilience overlapped for most species and reveal where resources could be invested for multispecies persistence. This novel simplified framework can aid decision making associated with conservation planning and prioritization for multiple species residing in overlapping, fragmented habitats; helping to identify key sites that warrant urgent conservation protection, with consideration of the need to adapt and respond to future change.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Aves , Mudança Climática , Extinção Biológica , Áreas Alagadas
12.
Angew Chem Int Ed Engl ; 57(47): 15359-15363, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30270504

RESUMO

We report on the asymmetric occupation of a 12-vertex cluster centered by a single metal atom. Three salts of related intermetalloid cluster anions, [Co@Sn6 Sb6 ]3- (1), [Co2 @Sn5 Sb7 ]3- (2), and [Ni2 @Sn7 Sb5 ]3- (3) were synthesized, which have pseudo-C4v -symmetric or pseudo-D4h -symmetric 12-vertex Sn/Sb shells and interstitial Co- ions or Ni atoms. Anion 1 is a very unusual single-metal-"centered" 12-atom cluster, with the inner atom being clearly offset from the cluster center for energetic reasons. Quantum chemistry served to assign atom types to the atomic positions and relative stabilities of this cluster type. The studies indicate that the structures are strictly controlled by the total valence electron count-which is particularly variable in ternary intermetalloid cluster anions. Preliminary 119 Sn NMR studies in solution, supported by quantum-chemical calculations of the shifts, illustrate the complexity regarding Sn:Sb distributions of such ternary systems.

13.
Glob Chang Biol ; 23(1): 256-268, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27151406

RESUMO

The existence of fine-grain climate heterogeneity has prompted suggestions that species may be able to survive future climate change in pockets of suitable microclimate, termed 'microrefugia'. However, evidence for microrefugia is hindered by lack of understanding of how rates of warming vary across a landscape. Here, we present a model that is applied to provide fine-grained, multidecadal estimates of temperature change based on the underlying physical processes that influence microclimate. Weather station and remotely derived environmental data were used to construct physical variables that capture the effects of terrain, sea surface temperatures, altitude and surface albedo on local temperatures, which were then calibrated statistically to derive gridded estimates of temperature. We apply the model to the Lizard Peninsula, United Kingdom, to provide accurate (mean error = 1.21 °C; RMS error = 1.63 °C) hourly estimates of temperature at a resolution of 100 m for the period 1977-2014. We show that rates of warming vary across a landscape primarily due to long-term trends in weather conditions. Total warming varied from 0.87 to 1.16 °C, with the slowest rates of warming evident on north-east-facing slopes. This variation contributed to substantial spatial heterogeneity in trends in bioclimatic variables: for example, the change in the length of the frost-free season varied from +11 to -54 days and the increase in annual growing degree-days from 51 to 267 °C days. Spatial variation in warming was caused primarily by a decrease in daytime cloud cover with a resulting increase in received solar radiation, and secondarily by a decrease in the strength of westerly winds, which has amplified the effects on temperature of solar radiation on west-facing slopes. We emphasize the importance of multidecadal trends in weather conditions in determining spatial variation in rates of warming, suggesting that locations experiencing least warming may not remain consistent under future climate change.


Assuntos
Mudança Climática , Microclima , Altitude , Clima , Temperatura , Reino Unido
14.
J Surg Oncol ; 115(3): 257-265, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28105636

RESUMO

BACKGROUND: The most cost-effective reconstruction after resection of bone sarcoma is unknown. The goal of this study was to compare the cost effectiveness of osteoarticular allograft to endoprosthetic reconstruction of the proximal tibia or distal femur. METHODS: A Markov model was used. Revision and complication rates were taken from existing studies. Costs were based on Medicare reimbursement rates and implant prices. Health-state utilities were derived from the Health Utilities Index 3 survey with additional assumptions. Incremental cost-effectiveness ratios (ICER) were used with less than $100 000 per quality-adjusted life year (QALY) considered cost-effective. Sensitivity analyses were performed for comparison over a range of costs, utilities, complication rates, and revisions rates. RESULTS: Osteoarticular allografts, and a 30% price-discounted endoprosthesis were cost-effective with ICERs of $92.59 and $6 114.77. One-way sensitivity analysis revealed discounted endoprostheses were favored if allografts cost over $21 900 or endoprostheses cost less than $51 900. Allograft reconstruction was favored over discounted endoprosthetic reconstruction if the allograft complication rate was less than 1.3%. Allografts were more cost-effective than full-price endoprostheses. CONCLUSIONS: Osteoarticular allografts and price-discounted endoprosthetic reconstructions are cost-effective. Sensitivity analysis, using plausible complication and revision rates, favored the use of discounted endoprostheses over allografts. Allografts are more cost-effective than full-price endoprostheses.


Assuntos
Artroplastia do Joelho/economia , Neoplasias Ósseas/cirurgia , Transplante Ósseo/economia , Osteossarcoma/cirurgia , Procedimentos de Cirurgia Plástica/economia , Artroplastia do Joelho/métodos , Neoplasias Ósseas/economia , Transplante Ósseo/métodos , Análise Custo-Benefício , Fêmur/cirurgia , Humanos , Articulação do Joelho/cirurgia , Cadeias de Markov , Osteossarcoma/economia , Procedimentos de Cirurgia Plástica/métodos , Tíbia/cirurgia , Transplante Homólogo
15.
Angew Chem Int Ed Engl ; 56(11): 3098-3102, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28194839

RESUMO

Extraction of a solid with the nominal composition "K2 GeBi" with 1,2-diaminoethane (en) in the presence of 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane (crypt-222) afforded the salt [K(crypt-222)]4 (Ge4 Bi14 ). The 18-atom Zintl anion (Ge4 Bi14 )4- has a heretofore unknown molecular topology, which can be thought of as the formal condensation product of two E113- cages along a shared Ge4 waist. In this way, (Ge4 Bi14 )4- represents the largest and most structurally complex Bi-containing polyanion. We describe its stepwise formation, its geometric and electronic structure, and comment on relative stabilities of isomers with different distributions of the four Ge atoms on the 18 positions that were investigated using DFT calculations.

16.
J Am Chem Soc ; 138(29): 9033-6, 2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27392253

RESUMO

The encapsulation of actinide ions in intermetalloid clusters has long been proposed but was never realized synthetically. We report the isolation and experimental, as well as quantum chemical, characterization of the uranium-centered clusters [U@Bi12](3-), [U@Tl2Bi11](3-), [U@Pb7Bi7](3-), and [U@Pb4Bi9](3-), upon reaction of (EE'Bi2)(2-) (E = Ga, Tl, E' = Bi; E = E' = Pb) and [U(C5Me4H)3] or [U(C5Me4H)3Cl] in 1,2-diaminoethane. For [U@Bi12](3-), magnetic susceptibility measurements rationalize an unprecedented antiferromagnetic coupling between a magnetic U(4+) site and a unique radical Bi12(7-) shell.

17.
Glob Chang Biol ; 22(10): 3332-40, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26990351

RESUMO

Diapause plays a key role in the life cycle of high latitude zooplankton. During diapause, animals avoid starving in winter by living in deep waters where metabolism is lower and met by lipid reserves. Global warming is therefore expected to shorten the maximum potential diapause duration by increasing metabolic rates and by reducing body size and lipid reserves. This will alter the phenology of zooplankton, impact higher trophic levels and disrupt biological carbon pumps. Here, we project the impacts of climate change on the key North Atlantic copepod Calanus finmarchicus under IPCC RCP 8.5. Potential diapause duration is modelled in relation to body size and overwintering temperature. The projections show pronounced geographic variations. Potential diapause duration reduces by more than 30% in the Western Atlantic, whereas in the key overwintering centre of the Norwegian Sea it changes only marginally. Surface temperature rises, which reduce body size and lipid reserves, will have a similar impact to deep-water changes on diapause in many regions. Because deep-water warming lags that at the surface, animals in the Labrador Sea could offset warming impacts by diapausing in deeper waters. However, the ability to control diapause depth may be limited.


Assuntos
Mudança Climática , Zooplâncton , Animais , Copépodes , Metamorfose Biológica , Estações do Ano
18.
Glob Chang Biol ; 22(11): 3814-3828, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27370903

RESUMO

The cultivation of grapevines for winemaking, known as viticulture, is widely cited as a climate-sensitive agricultural system that has been used as an indicator of both historic and contemporary climate change. Numerous studies have questioned the viability of major viticulture regions under future climate projections. We review the methods used to study the impacts of climate change on viticulture in the light of what is known about the effects of climate and weather on the yields and quality of vineyard harvests. Many potential impacts of climate change on viticulture, particularly those associated with a change in climate variability or seasonal weather patterns, are rarely captured. Key biophysical characteristics of viticulture are often unaccounted for, including the variability of grapevine phenology and the exploitation of microclimatic niches that permit successful cultivation under suboptimal macroclimatic conditions. We consider how these same biophysical characteristics permit a variety of strategies by which viticulture can adapt to changing climatic conditions. The ability to realize these strategies, however, is affected by uneven exposure to risks across the winemaking sector, and the evolving capacity for decision-making within and across organizational boundaries. The role grape provenance plays in shaping perceptions of wine value and quality illustrates how conflicts of interest influence decisions about adaptive strategies within the industry. We conclude by considering what lessons can be taken from viticulture for studies of climate change impacts and the capacity for adaptation in other agricultural and natural systems.


Assuntos
Agricultura , Mudança Climática , Vitis , Clima , Previsões , Tempo (Meteorologia)
19.
Environ Sci Technol ; 50(8): 4502-12, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27019216

RESUMO

Hypoxia is a global and increasingly important stressor in aquatic ecosystems, with major impacts on biodiversity worldwide. Hypoxic waters are often contaminated with a wide range of chemicals but little is known about the interactions between these stressors. We investigated the effects of hypoxia on the responses of zebrafish (Danio rerio) embryos to copper, a widespread aquatic contaminant. We showed that during continuous exposures copper toxicity was reduced by over 2-fold under hypoxia compared to normoxia. When exposures were conducted during 24 h windows, hypoxia reduced copper toxicity during early development and increased its toxicity in hatched larvae. To investigate the role of the hypoxia signaling pathway on the suppression of copper toxicity during early development, we stabilized the hypoxia inducible factor (HIF) pathway under normoxia using a prolyl-4-hydroxylase inhibitor, dimethyloxalylglycine (DMOG) and demonstrated that HIF activation results in a strong reduction in copper toxicity. We also established that the reduction in copper toxicity during early development was independent of copper uptake, while after hatching, copper uptake was increased under hypoxia, corresponding to an increase in copper toxicity. These findings change our understanding of the current and future impacts of worldwide oxygen depletion on fish communities challenged by anthropogenic toxicants.


Assuntos
Cobre/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Aminoácidos Dicarboxílicos/farmacologia , Animais , Cobre/metabolismo , Embrião não Mamífero/metabolismo , Larva , Oxigênio/metabolismo , Transdução de Sinais , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/embriologia
20.
Nucleic Acids Res ; 42(Database issue): D802-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24194600

RESUMO

The International Mouse Phenotyping Consortium (IMPC) web portal (http://www.mousephenotype.org) provides the biomedical community with a unified point of access to mutant mice and rich collection of related emerging and existing mouse phenotype data. IMPC mouse clinics worldwide follow rigorous highly structured and standardized protocols for the experimentation, collection and dissemination of data. Dedicated 'data wranglers' work with each phenotyping center to collate data and perform quality control of data. An automated statistical analysis pipeline has been developed to identify knockout strains with a significant change in the phenotype parameters. Annotation with biomedical ontologies allows biologists and clinicians to easily find mouse strains with phenotypic traits relevant to their research. Data integration with other resources will provide insights into mammalian gene function and human disease. As phenotype data become available for every gene in the mouse, the IMPC web portal will become an invaluable tool for researchers studying the genetic contributions of genes to human diseases.


Assuntos
Bases de Dados Genéticas , Camundongos Knockout , Fenótipo , Animais , Ontologias Biológicas , Internet , Camundongos
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