Superconducting vortices in CeCoIn5: toward the Pauli-limiting field     

Bianchi AD  Kenzelmann M  Debeer-Schmitt L  White JS  Forgan EM  Mesot J  Zolliker M  Kohlbrecher J  Movshovich R  Bauer ED  Sarrao JL  Fisk Z  Petrovic C  Eskildsen MR 《Science (New York, N.Y.)》2008,319(5860):177-180

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How well do proxy species models inform conservation of surrogate species?     

Loman  Zachary G.  Deluca  William V.  Harrison  Daniel J.  Loftin  Cynthia S.  Schwenk  W. Scott  Wood  Petra B. 《Landscape Ecology》2021,36(10):2863-2877

Landscape Ecology - Proxy species, which represent suites of organisms with similar habitat requirements, are common in conservation. Landscape Capability (LC) models aim to quantify the...  相似文献   

Collard landraces are novel sources of glucoraphanin and other aliphatic glucosinolates          下载免费PDF全文

Zachary Stansell  Wendy Cory  David Couillard  Mark Farnham 《Plant Breeding》2015,134(3):350-355

The glucosinolate make‐up of the edible parts of some Brassica oleracea L. crops has been investigated previously, but the leafy‐green collard (B. oleracea var. viridis) remains relatively unstudied on this topic. Due to this lack of information, a collection of US landraces was examined for glucosinolate content of leaves. The specific objectives of this examination were to compare levels of certain glucosinolates among the conserved collard landraces, identify any individuals with a distinct glucosinolate profile and determine the potential of collard as a target for chemoprotective‐based plant breeding. During winter 2010/2011, 81 collard landraces, four other viridis and four collard cultivars were evaluated in the field and harvested leaves were assayed for glucosinolates. In a subsequent study, 19 selected landraces plus the cultivars were included in a repeat trial in 2012/2013. Eighteen collard landraces contained relatively high levels of glucoraphanin in leaves in both years, and three (designated G 32575, G 32580, G 32586 in the US National Plant Germplasm System) were found to contain glucoraphanin in excess of 9.5 μmol/g DM. The examined landraces are rich sources of important aliphatic glucosinolates, previously thought to be most abundant in other B. oleracea vegetables.  相似文献   

Dual-axis electron tomography: a new approach for investigating the spatial organization of wood cellulose microfibrils     

Ping Xu  Lloyd A. Donaldson  Zachary R. Gergely  L. Andrew Staehelin 《Wood Science and Technology》2007,41(2):101-116

We have employed dual-axis electron tomography to investigate the 3D organization of cellulose microfibrils in plastic resin-embedded, delignified cell walls of radiata pine early wood. The ∼ 1 nm thick tomographic slices produced in this study provided for a resolution of ∼ 2 nm in the cross-section of the slices throughout the 150 nm thick plastic sections. This resolution is sufficient to resolve individual cellulose microfibrils and to map the 3D organization of the cellulose microfibrils within the S2 layer of the secondary cell walls. The individual cellulose microfibrils measure ∼ 3.2 nm in diameter, and appear to consist of a ∼ 2.2 nm unstained core and a ∼ 0.5 nm thick surface layer that is lightly stained. Both individual and clustered cellulose microfibrils are seen surrounded by more heavily stained and irregularly shaped residual lignin and hemicellulose. The tightness of packing of the cellulose microfibrils in the cluster varies along the thickness of the section. These findings demonstrate that dual-axis electron tomography is a technique that can provide new insights into the 3D organization of cellulose microfibrils in plant cell walls.  相似文献   

Microhabitat use by southern brook trout (Salvelinus fontinalis) in a headwater North Carolina stream     

Zachary W. Anglin  Gary D. Grossman 《Ecology of Freshwater Fish》2013,22(4):567-577

Brook trout are the one of the only Salvelinus species native to eastern North America and range from Canada to Georgia. Very little is known, however, about the ecology of the southern form of this species. We quantified microhabitat use of southern brook trout in Ball Creek NC, a third‐order stream, during six seasonal samples (summer 2010, autumn 2010, spring 2011, summer 2011, autumn 2011 and spring 2012). In general, trout preferentially occupied deeper microhabitats with lower mean velocities and higher amounts of erosional substrata than were randomly available. Older trout (1+ and 2+) occupied deeper microhabitats with lower mean velocities than yearling trout. These microhabitats typically represent ‘plunge pools’. Southern brook trout also occupied focal point velocities that were statistically indistinguishable from optimal velocities calculated for rainbow trout in the same system and thus may chose microhabitats that maximise net energy gain. Southern brook trout are found in isolated populations, and management strategies should focus on the preservation of plunge pool habitat for conservation of this subspecies.  相似文献   

Combining ground penetrating radar methodologies enables large-scale mapping of soil horizon thickness and bulk density in boreal forests     

Zachary W. Gates  Lakshman W. Galagedara  Susan E. Ziegler 《Soil Use and Management》2023,39(4):1289-1303

Forest soil properties must be observed with the appropriate resolution by depth and landscape area to understand biogeomorphological controls on soil carbon (C). These observations, particularly in boreal forests, have been limited because of the poor resolution and unavailability of physical soil sampling results, especially for soil bulk density measurements. Ground penetrating radar (GPR) has been demonstrated to non-destructively and continuously estimate forest soil properties required in Cstock estimates, such as soil horizon thickness and soil bulk density, across small spatial scales and shallow depths. Yet, successful small-scale forest GPR approaches represent a potential opportunity to obtain soil property estimates at relevant resolution and depth across forest landscapes, enabling improvement to much needed soil mapping and stock estimates. This review discusses the existing soil property studies that utilize ground penetrating radar (GPR) and explores how the adaptation of GPR methodology can contribute to investigating soils in forest landscapes. We have identified common GPR surveying practices, data processing steps and interpretation methods employed in multiple studies. These approaches have proven effective in obtaining higher-resolution estimates of important soil properties, such as bulk density and horizon thickness, within small-scale forest plots. By applying relevant findings in this review to our own boreal forest investigation across an 80 m hillslope transect, we provide recommendations on how to tailor GPR methodology for landscape-scale estimates of soil horizon thickness and bulk density to examine forest soil property distribution. These findings should enable the future collection of soil datasets informing the distribution of soil C stocks and their relationship to landscape features, and thus their controls and responses to climate and environmental change.  相似文献   

Connectivity and flow regime direct conservation priorities for pelagophil fishes     

Robert Mollenhauer  Shannon K. Brewer  Joshuah S. Perkin  Dusty Swedberg  Maeghen Wedgeworth  Zachary D. Steffensmeier 《水产资源保护:海洋与淡水生态系统》2021,31(11):3215-3227

1. Dam construction threatens global aquatic biodiversity by fragmenting stream networks and altering flow regimes. The negative effects of dams are exacerbated by increased drought periods and associated water withdrawals, especially in semi-arid regions. Stream fishes are particularly threatened owing to their mobile nature and requirement for multiple habitats to complete their life cycles. An understanding of relationships with fragmentation and flow regimes, particularly as coarse-scale (e.g. catchment) constraints on species distributions, is essential for stream fish conservation strategies.
2. Prairie chub (Macrhybopsis australis) is a small-bodied minnow (Cyprinidae) with poorly understood ecology endemic to the North American Great Plains. Suspected declines in abundance and extirpations have resulted in conservation interest for prairie chub at state and federal levels. Prairie chub is thought to share its reproductive strategy with pelagic-broadcast spawning minnows (pelagophils). Freshwater pelagic-broadcast spawning fishes have been disproportionately affected by fragmentation and streamflow alteration globally.
3. Relationships of prairie chub occurrence with coarse-scale fragmentation and streamflow metrics were examined in the upper Red River catchment. Occurrence probability was modelled using existing survey data, while accounting for variable detection. The modelled relationships were used to project the distribution of prairie chub in both a wet and dry climatic period.
4. The probability of prairie chub occurrence was essentially zero at sites with higher densities of upstream dams, but increased sharply with increases in flow magnitude, downstream open mainstem, and flood duration. The projected distribution of prairie chub was broader than indicated by naïve occurrence, but similar in both climatic periods. The occurrence relationships are consistent with the hypotheses of pelagic broadcast spawning and represent coarse-scale constraints that are useful for identifying areas of the stream network with higher potential for finer-scale prairie chub conservation and recovery efforts. In addition to informing pelagophil conservation, the relationships are also applicable to pelagic-broadcast spawning fishes in marine environments.

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Birding by Ear: A Study of Recreational Specialization and Soundscape Preference     

Zachary D. Miller  Julia L. Sharp  Robert B. Powell  J. Drew Lanham 《Human Dimensions of Wildlife》2014,19(6):498-511

Soundscapes have become recognized as an important natural resource. The traditional human-made versus natural soundscape comparison currently used in recreational resource management is challenged by borrowing soundscape components (i.e., biophony, anthrophony, geophony) from soundscape ecology. This article evaluated the soundscape preference of birders. A three-component model of recreational specialization was used to evaluate how recreationists differ in their preference for soundscape components. Data from in-person surveys collected at The Audubon Center and Sanctuary at Francis Beidler Forest in Harleyville, South Carolina were used in combination with surveys from online birding list servers to obtain a sample of 415 individuals with varying levels of specialization. The findings suggest soundscape preference exists as biophony, geophony, and anthrophony and that more specialized birders found geophony to be significantly more annoying than less specialized birders. Additionally, the skill and knowledge component of specialization best explained the difference in geophony preference among birders.  相似文献   

Fishing for health: Do the world’s national policies for fisheries and aquaculture align with those for nutrition?     

John Zachary Koehn  Edward H Allison  Karen Villeda  Zelin Chen  Marisa Nixon  Emily Crigler  Lily Zhao  Michelle Chow  Bapu Vaitla  Shakuntala H Thilsted  Joeri Scholtens  Christina C Hicks  Neil Andrew 《Fish and Fisheries》2022,23(1):125-142

Aquatic foods are rich in micronutrients essential to human health, and fisheries and aquaculture are increasingly recognized for their capacity to contribute to reducing global micronutrient deficiencies and diet-based health risks. Whether fisheries and aquaculture sector and public health nutrition policies align to meet this goal, however, is unclear. Do fisheries and aquaculture policies have explicit nutrition and public health objectives? Do public health nutrition policies recognize the contribution of aquatic foods? Using content analysis, we assessed the alignment of objectives in national fisheries and public health nutrition policies. We further determined conditions associated with varying levels of cohesion among policies in these sectors or domains. We found that 77 of 158 national fisheries policies identified nutrition as a key objective in the sector, and 68 of 165 public health nutrition policies identified the importance of fish and shellfish consumption as key objectives. More recent policies were associated with improved coherence among sectors. International organization presence in policy development was also associated with greater coherence. Countries with higher overweight prevalence had fisheries and public health nutrition policies that were not aligned. There has been a promising recent trend for improved alignment of objectives between fisheries and public health nutrition policies, but more targeted and systematic policy approaches are needed to realize the potential contribution of nutrient-rich fish and shellfish to healthier food systems.  相似文献   

Peripheral nerve biopsy for diagnosis of globoid cell leukodystrophy in a dog   总被引：1，自引：0，他引：1  

D S Vicini  L G Wheaton  J F Zachary  A J Parker 《Journal of the American Veterinary Medical Association》1988,192(8):1087-1090

Saphenous nerve biopsy was performed to diagnose globoid cell leukodystrophy in a 3-month-old West Highland White Terrier. The dog had progressive neurologic disease that appeared to involve the cerebellum, spinal cord, and lower motor neurons to the hind limbs. Light and transmission electron microscopic findings of the nerve biopsy specimen established the diagnosis. Peripheral nerve biopsy may provide a reliable antemortem method for diagnosis of globoid cell leukodystrophy.  相似文献