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21.
Rational management of plant diseases, both economically and environmentally, involves assessing risks and the costs associated with both correct and incorrect tactical management decisions to determine when control measures are warranted. Decision support systems can help to inform users of plant disease risk and thus assist in accurately targeting events critical for management. However, in many instances adoption of these systems for use in routine disease management has been perceived as slow. The under-utilization of some decision support systems is likely due to both technical and perception constraints that have not been addressed adequately during development and implementation phases. Growers' perceptions of risk and their aversion to these perceived risks can be reasons for the \"slow\" uptake of decision support systems and, more broadly, integrated pest management (IPM). Decision theory provides some tools that may assist in quantifying and incorporating subjective and/or measured probabilities of disease occurrence or crop loss into decision support systems. Incorporation of subjective probabilities into IPM recommendations may be one means to reduce grower uncertainty and improve trust of these systems because management recommendations could be explicitly informed by growers' perceptions of risk and economic utility. Ultimately though, we suggest that an appropriate measure of the value and impact of decision support systems is grower education that enables more skillful and informed management decisions independent of consultation of the support tool outputs. 相似文献
22.
CASE HISTORY: A 2-year-old female Siberian Husky was presented with a 6-month history of sneezing and mucous discharge from the right nostril. CLINICAL FINDINGS: Reduced airflow through the right nostril was evident. Radiographs showed subtle loss of detail of turbinates within the right nasal chamber. Rhinoscopy revealed swollen and erythematous turbinates and a white mass within the caudal aspect of the right nasal cavity. Histopathologically, there was a heavy mixed inflammatory infiltrate in the submus- cosa of the right turbinate, and the presence of fungal hyphae and spores in the white mass. A heavy growth of Scedosporium apiospermum was cultured from the mass. DIAGNOSIS: Chronic rhinitis of the right nasal cavity and infection with S. apiospermum. CLINICAL RELEVANCE: This is the first reported case of S. apiospermum isolated from the nasal cavity of a dog in New Zealand. Fungal culture is necessary to differentiate this fungus from Aspergillus spp. 相似文献
23.
de Melo Rafaela Leitão Correia Dutra Júnior Wilson Moreira Palhares Liliane Olímpio de Moura Ferreira Débora Nathália de Aquino Rafael Santos Cordeiro Manso Helena Emília Cavalcanti 《Tropical animal health and production》2019,51(5):1057-1063
Tropical Animal Health and Production - The objective of this study was to evaluate the biochemical, behavioral, and physiological parameters in pregnant sows of native and improved crossbreeds... 相似文献
24.
Ignacio Leyva-Valencia Jesús Ernestina Hernndez-Castro Christine J. Band-Schmidt Andrew D. Turner Alison O&#x;Neill Erick J. Núez-Vzquez David J. Lpez-Corts Jos J. Bustillos-Guzmn Francisco E. Hernndez-Sandoval 《Marine drugs》2021,19(2)
Most of the shellfish fisheries of Mexico occur in the Gulf of California. In this region, known for its high primary productivity, blooms of diatoms and dinoflagellates are common, occurring mainly during upwelling events. Dinoflagellates that produce lipophilic toxins are present, where some outbreaks related to okadaic acid and dinophisystoxins have been recorded. From January 2015 to November 2017 samples of three species of wild bivalve mollusks were collected monthly in five sites in the southern region of Bahía de La Paz. Pooled tissue extracts were analyzed using LC-MS/MS to detect lipophilic toxins. Eighteen analogs of seven toxin groups, including cyclic imines were identified, fortunately individual toxins did not exceed regulatory levels and also the total toxin concentration for each bivalve species was lower than the maximum permitted level for human consumption. Interspecific differences in toxin number and concentration were observed in three species of bivalves even when the samples were collected at the same site. Okadaic acid was detected in low concentrations, while yessotoxins and gymnodimines had the highest concentrations in bivalve tissues. Although in low quantities, the presence of cyclic imines and other lipophilic toxins in bivalves from the southern Gulf of California was constant. 相似文献
25.
Guardado-Félix Daniela Pérez-Carrillo Esther Heredia-Olea Erick Serna-Saldivar Sergio O. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):226-232
Plant Foods for Human Nutrition - Corn kernels were soaked with different selenium (Se) solutions (0, 12 or 24 mg Na2SeO3/L), sprouted for different times and then lime-cooked for the... 相似文献
26.
Méndez-Zúñiga Sergio M. Corrales-García Joel E. Gutiérrez-Grijalva Erick P. García-Mateos Rosario Pérez-Rubio Verónica Heredia José Basilio 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(4):501-507
Plant Foods for Human Nutrition - Mexico is the world’s largest producer, exporter, and consumer of avocados. “Hass” avocado is the most commercialized cultivar, while the native... 相似文献
27.
Cyanobacteria, particularly thermophilic strains, represent an important potential source of EPSs, harboring structural complexity that predicts diverse and specific bioactive potential. The thermophilic cyanobacteria Gloeocapsa gelatinosa, isolated from a natural hot source in Ain Echfa (Tunisia), was cultivated in a cylindrical reactor, and the production of biomass and EPSs was investigated. Results revealed that the strain is amongst the most efficient EPSs producers (0.89 g L−1) and that EPSs production was not correlated with the growth phase. EPSs were sulfated heteropolysaccharides containing carbohydrates (70%) based on nine different monosaccharides, mainly mannose (22%), and with the presence of two uronic acids. EPSs were formed by two polymers moieties with a molecular weight of 598.3 ± 7.2 and 67.2 ± 4.4 kDa. They are thermostable in temperatures exceeding 100 °C and have an anionic nature (zeta potential of −40 ± 2 mV). Atomic force microscopy showed that EPSs formed multimodal lumps with 88 nm maximum height. EPSs presented high water holding capacity (70.29 ± 2.36%) and solubility index (97.43 ± 1.24%), and a strong bivalent metal sorption capacity especially for Cu2+ (91.20 ± 1.25%) and Fe2+ (75.51 ± 0.71%). The antioxidant activity of G. gelatinosa EPSs was investigated using four methods: the β-carotene-bleaching activity, DPPH assays, iron-reducing activity, and metal-chelating activity. EPS has shown high potential as free radicals’ scavenger, with an IC50 on DPPH (0.2 g L−1) three-fold lower than ascorbic acid (0.6 g L −1) and as a metal chelating activity (IC50 = 0.4 g L−1) significantly lower than EDTA. The obtained results allow further exploration of the thermophilic G. gelatinosa for several biotechnological and industrial applications. 相似文献
28.
The development of cost‐effective and nutritionally adequate formulated feeds is a key step for developing sustainable technologies for new aquaculture species. There has been many research effort for over 30 years on feed development for spiny lobsters, but amazingly, poor performance of formulated feeds remains one of the major obstacles to progressing commercial aquaculture of these crustaceans. This is partially due to a lack of information on how spiny lobsters digest and assimilate formulated feeds. The aim of this review is to integrate recent information on the digestive physiology of spiny lobsters to identify areas where further studies are needed for advancing to more physiologically tailored formulated feeds. Increasing the efficiency of mechanical and chemical digestion is imperative for better digestion of formulated feeds. This is likely to be achieved by improving feed format, reducing the particle size of ingredients, using digestible binders, preprocessing or selecting more soluble macronutrients and supplementing feeds with additives such as pH buffers, emulsifying agents and/or exogenous enzymes. Future research needs to adopt a holistic approach for investigating the digestive processes in spiny lobsters by focusing on digestion as well as downstream processes. The protein‐sparing effect of lipids and carbohydrates on spiny lobster metabolism is of a particular significance as the spiny lobster metabolism is strongly directed towards the use of protein. This review provides important insights, practical solutions and key research directions to improve both our understanding of spiny lobster digestive physiology and the performance of formulated feeds for spiny lobsters. 相似文献
29.
Erick M. G. Cordeiro James F. Campbell Thomas W. Phillips Kimberly A. With 《Landscape Ecology》2018,33(11):1881-1894
Context
Although animal movement behaviors are influenced by spatial heterogeneity, such behaviors can also generate spatial heterogeneity via interactions with the emergent spatial structure and other individuals (i.e., the social landscape).Objective
Elucidate the behavioral and ecological mechanisms of pattern formation in a homogeneous resource landscape.Methods
We analyzed the movement pathways and space-use patterns of the lesser grain borer (Rhyzopertha dominica) within homogeneous resource landscapes (wheat kernels). Experimental trials consisted of individual beetles foraging alone or paired with a member of the same or different sex.Results
We identified two sources of pattern formation: (1) beetles were attracted to areas where they or another beetle had previously fed, leading to increased patchiness via positive reinforcement; and (2) the presence of conspecifics affected whether and at what scales patchiness occurred. Solitary males had lower rates of movement and less tortuous pathways than solitary females, but both sexes generated fine-scale patchiness in the resource distribution. Patchy resource landscapes were also generated by male–female pairs, but not by same-sex pairings. Paired females in particular exhibited significantly greater daily net displacements and more random space use than solitary females.Conclusions
Pattern formation is a complex process, even in a relatively simple, homogeneous resource landscape. In particular, patterns created by individuals when foraging alone versus in pairs underscores how social interactions can fundamentally alter the resultant pattern of heterogeneity that emerges in resource landscapes.30.
Douglas J. Huber DVM MS Diplomate ABVP Erick L. Egger DVM Diplomate ACVS Susan P. James PhD 《Veterinary surgery : VS》1999,28(4):260-267
OBJECTIVE: To evaluate the effect of knotting method on the mechanical properties of large diameter nonabsorbable monofilament suture materials. STUDY DESIGN: In vitro mechanical evaluation. METHODS: A conventional square knot was compared with the surgeon's knot, sliding half-hitch, and clamped square knot. Knotted suture loops were created in a uniform manner and acutely tensioned to failure (20 mm/min loading rate; n = 20 per knot type for each material). Stiffness, yield, and failure characteristics of USP #2 nylon, #2 polybutester, #2 polypropylene, 27 kg test monofilament nylon fishing line, and 27 kg nylon leader material were evaluated. RESULTS: Compared with a conventional square knot, a surgeon's knot decreased stiffness for #2 polypropylene, 27 kg fishing line, and 27 kg leader (P < .05). A sliding half-hitch weakened all materials except 27 kg leader (P < .05). Clamping the first throw of a square knot increased the stiffness of 27 kg leader loops (P < .05). CONCLUSIONS: Based on clinically relevant parameters (stiffness and yield), knotting method had no effect on #2 nylon and #2 polybutester. The surgeon's knot is not recommended for #2 polypropylene and 27 kg fishing line and leader material. A sliding half-hitch decreased the yield of leader material. Clamping the first throw of a square knot had no adverse effects on acute properties of tested materials; it increased the stiffness for leader material. CLINICAL RELEVANCE: Knotting method does influence the structural properties of suture materials and should be considered when tying knots under tension. 相似文献