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Background
Inkjet micropatterning is a versatile deposition technique with broad applications in numerous fields. However, its application in plant science is largely unexplored. Leaf expansion is one of the most important parameters in the field of plant science and many methods have been developed to examine differential expansion rates of different parts of the leaf lamina. Among them, methods based on the tracking of natural landmarks through digital imaging require a complicated setup in which the leaf must remain fixed and under tension. Furthermore, the resolution is limited to that of the natural landmarks, which are often difficult to find, particularly in young leaves. To study the fine scale expansion dynamics of the leaf lamina using artificial landmarks it is necessary to place small, noninvasive marks on a leaf surface and then recover the location of those marks after a period of time. 相似文献2.
Tuskan GA Difazio S Jansson S Bohlmann J Grigoriev I Hellsten U Putnam N Ralph S Rombauts S Salamov A Schein J Sterck L Aerts A Bhalerao RR Bhalerao RP Blaudez D Boerjan W Brun A Brunner A Busov V Campbell M Carlson J Chalot M Chapman J Chen GL Cooper D Coutinho PM Couturier J Covert S Cronk Q Cunningham R Davis J Degroeve S Déjardin A Depamphilis C Detter J Dirks B Dubchak I Duplessis S Ehlting J Ellis B Gendler K Goodstein D Gribskov M Grimwood J Groover A Gunter L Hamberger B Heinze B 《Science (New York, N.Y.)》2006,313(5793):1596-1604
We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport. 相似文献
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Patrick K. Mitchell Brittany D. Cronk Ian E. H. Voorhees Derek Rothenheber Renee R. Anderson Timothy H. Chan Brian R. Wasik Edward J. Dubovi Colin R. Parrish Laura B. Goodman 《Journal of veterinary diagnostic investigation》2021,33(2):191
Epidemics of H3N8 and H3N2 influenza A viruses (IAVs) in dogs, along with recognition of spillover infections from IAV strains typically found in humans or other animals, have emphasized the importance of efficient laboratory testing. Given the lack of active IAV surveillance or immunization requirements for dogs, cats, or horses imported into the United States, serotype prediction and whole-genome sequencing of positive specimens detected at veterinary diagnostic laboratories are also needed. The conserved sequences at the ends of the viral genome segments facilitate universal amplification of all segments of viral genomes directly from respiratory specimens. Although several methods for genomic analysis have been reported, no optimization focusing on companion animal strains has been described, to our knowledge. We compared 2 sets of published universal amplification primers using 26 IAV-positive specimens from dogs, horses, and a cat. Libraries prepared from the resulting amplicons were sequenced using Illumina chemistry, and reference-based assemblies were generated from the data produced by both methods. Although both methods produced high-quality data, coverage profiles and base calling differed between the 2 methods. The sequence data were also used to identify the subtype of the IAV strains sequenced and then compared to standard PCR assays for neuraminidase types N2 and N8. 相似文献
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Ireland HE Clutterbuck A Cloquet JP Thurston MI Williams PA Cronk QC Dewey FM Williams JH 《Journal of agricultural and food chemistry》2004,52(26):7804-7808
Gum arabic from Acacia senegal is commonly used as an additive in foodstuffs. Adulteration of gum arabic by other gums is a potential problem for reasons of safety and quality. This study aimed to develop and evaluate the use of enzyme-linked immunosorbent assays (ELISAs) for the detection of potential adulterants of gum arabic. Indirect competitive ELISAs (IC-ELISAs) were developed using the monoclonal antibodies SY CC7 (A. senegal), SY HH3 (Acacia seyal), and SY J1A1 (Combretum erythrophyllum). All IC-ELISAs had a working range of 0.005-10 mg/mL. The antibodies used were tested using the IC-ELISAs for cross-reactivity with other Acacia species and other gums. The antibodies were very specific for their respective antigens. Significant cross-reactivity was found for SY CC7 (between A. senegal and A. melliferae) and SY J1A1 (between C. erythrophyllum and A. seyal). The IC-ELISA was adapted further to test confectionery samples for the presence of gum arabic, which was successful, although recovery rates were reduced. Both IC- and plate trapped antigen ELISA (PTA-ELISA) formats were able to distinguish an adulterated sample of gum arabic when blended with either A. seyal or C. erythrophyllum. The PTA-ELISA was more sensitive for A. seyal than the IC-ELISA, but both were equally sensitive for C. erythrophyllum. The results suggest that the antibodies SY CC7, SY HH3, and SY J1A1 could be used in combination with each other for the detection of potential adulterants of A. senegal and the detection of gum arabic in foodstuffs. 相似文献
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Q.C.B. Cronk 《Biological conservation》1983,26(2):163-174
Redwood Trochetiopsis erythroxylon was still a common tree when the English East India Company colonised St Helena in 1659. It was, however, the most important indigenous plant to the settlers as its bark is suitable for tanning leather, and it provided the best timber. Within 50 years it was very scarce but was saved from extinction by being planted in island gardens from the early 18th century onwards. By the end of the 19th century only two wild trees remained even though the pressure of exploitation had by then been removed by the introduction of new timber trees and the importation of timber. It still fails to regenerate in St Helena and only through an exact knowledge of its requirements can vigorous trees be re-established there. 相似文献
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Junghee Yoon DVM PhD Daniel A. Feeney DVM MS Daniel E. Cronk Kari L. Anderson DVM Laura E. Ziegler DVM 《Veterinary radiology & ultrasound》2004,45(6):542-546
A 15-year retrospective analysis of histologically proven canine and feline mediastinal malignancies at the University of Minnesota was conducted to identify patients imaged by computed tomography (CT). The goal of the study was to characterize the CT appearance, to determine if there were any tumor type-specific appearances, and to clarify the role of CT in patients with mediastinal masses. Fourteen patients meeting these criteria were available for evaluation. The masses were characterized based on the presence or absence of contrast enhancement, internal architecture, size, extent of local invasion, the presence of pleural fluid, and the presence of regional vascular invasion. Within the limits of this study and the histopathologic information available, there appeared to be no clinically exploitable relationship between the CT appearance and the histologic characterization of the mass. However, CT does provide reasonably accurate local staging information. 相似文献
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Q.C.B. Cronk 《Biological conservation》1980,17(3):207-219
The available information on the ten species of endemic vascular plants recorded from Ascension Island (including Oldenlandia adscensionis (DC.) Cronk and Xiphopteris ascensionense (Hieron.) Cronk for which new combinations are proposed) is summarised. The present state of the population is given for each species, reasons for extinction or survival are suggested and the need for conservation is discussed. When the island was discovered it was almost barren with only about 25 indigenous vascular plants. The rubiaceous shrub Oldenlandia adscensionis has become extinct and three other species are possibly extinct. The rest were observed in 1976. The main cause of this extinction is the introduction of alien plants which is now irreversible. It is therefore probable that further extinction will follow. 相似文献
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Feeney DA Jessen CR Weichselbaum RC Cronk DE Anderson KL 《American journal of veterinary research》2003,64(10):1242-1247
OBJECTIVE: To determine the relationship between surface emission rate of gamma radiation and urine concentration of I131 (urine radioactivity) during the period 7 to 21 days after oral or SC administration of I131 to hyperthyroid cats. ANIMALS: 47 hyperthyroid cats administered I131 PO and 24 hyperthyroid cats administered I131 SC. PROCEDURE: A dose of I131 (1.78 to 2.04 X 10(2) MBq [4.8 to 5.5 mCi]) was administered orally. Surface emission at the skin adjacent to the thyroid gland on days 7, 10, 14, 18, and 21 and number of counts/30 s in a urine sample (1 mL, obtained via cystocentesis) on days 7, 14, and 21 after oral administration were measured. Effective half-life (T1/2E) was derived for each point. Surface emission thresholds for maximum urine radioactivity values were established. A dose of I131 (1.48 X 10(2) MBq [4.0 mCi]) was administered SC. Urine radioactivity and surface emission rates for SC administration were compared with values for oral administration. RESULTS: The T1/2E for surface emissions and urine radioactivity progressively increased toward values for physical T1/2 over time. The T1/2E for surface emissions was 2.19 to 4.70 days, and T1/2E for urine radioactivity was 2.16 to 3.67 days. Surface emission rates had a clinically useful threshold relationship to maximum urine concentrations of I131. CONCLUSIONS AND CLINICAL RELEVANCE: Surface emission rates for cats administered I131 appeared useful in determining upper limits (threshold) of urine radioactivity and are a valid method to assess the time at which cats can be discharged after I131 administration. 相似文献
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Hannes Dempewolf Loren H. Rieseberg Quentin C. Cronk 《Genetic Resources and Crop Evolution》2008,55(8):1141-1157
Despite current recognition as the largest family of flowering plants (23,000 species ± 1000; Anderberg et al. 2007), the Compositae is home to comparatively few important crop species. To assess domestication levels in the Compositae, we
developed an index that categorizes taxa according to the strength of domestication. Most Compositae species that are used
by humans exhibit little or no evidence of domestication and only a handful have been strongly domesticated. Although the
Compositae (along with Orchidaceae) has few domesticated taxa compared to other large families such as Fabaceae or Poaceae,
Compositae species have features that should make them suitable for domestication and human consumption. These include high
species diversity, global geographic distribution, good seed storability, and good seed oil quality. We propose that the paucity
of domesticated species in this family can be attributed to a variety of factors, chiefly the prevalence of secondary defence
compounds, the lack of carbohydrates that can be digested by the human gut and the predominantly mechanical or wind-dependent
seed dispersal syndrome. We also discuss the relevance of genetic and cultural factors. Although few Compositae crops currently
play a major role in global agriculture, many species hold unexploited potential, especially as novel crops for food and industrial
applications. 相似文献
10.
Qin Yuan Sebastian G. Llanos‐Soto Jody L. Gangloff‐Kaufmann Joellen M. Lampman Matthew J. Frye Meghan C. Benedict Rebecca L. Tallmadge Patrick K. Mitchell Renee R. Anderson Brittany D. Cronk Bryce J. Stanhope Ava R. Jarvis Manigandan Lejeune Randall W. Renshaw Melissa Laverack Elizabeth M. Lamb Laura B. Goodman 《Zoonoses and public health》2020,67(6):684-696
Schoolyards and suburban parks are two environments where active tick surveillance may inform local management approaches. Even in a state such as New York with a robust active tick surveillance programme operated by the state Department of Health, these settings are not routinely covered. The goal of this study was to highlight the importance of active surveillance for tick‐borne pathogens by describing their prevalence in ticks collected from schoolyards and suburban parks and to guide the use of integrated pest management in these settings. Tick dragging was performed in three regions of New York State: Long Island, the Lower Hudson Valley and the Capital Region. A total of 19 schoolyards and 32 parks were sampled. The location, habitat and weather at the time of tick collection were recorded. Ticks were speciated and tested for the presence of 17 pathogens with a novel application of nanoscale real‐time PCR. The causative agents of Lyme disease, anaplasmosis, babesiosis and Powassan virus disease were all detected from Ixodes scapularis in various sites throughout the capital region and south‐eastern counties of New York state. The most common agent detected was Borrelia burgdorferi, and coinfection rates were as high as 36%. This surveillance study also captured the first of the invasive Asian longhorned tick species, Haemaphysalis longicornis, in New York state (collected 2 June 2017). Results from this study highlight the importance of collaborative efforts and data sharing for improvement of surveillance for tick‐borne disease agents. 相似文献
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