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1.
Although knowledge of the bioactive compounds produced by species inhabiting coastal waters is increasing, little is known about the bioactive potential produced by marine species occupying deeper habitats with high biodiversity and productivity. Here, we investigate about the bioactive potential of molecules produced by species that inhabit the crinoid beds, a poorly known essential fish habitat affected by trawling, wherein large amounts of commercial and noncommercial species are discarded. Based on a trawl survey conducted in 2019, 14% of the 64 species discarded on crinoid beds produce molecules with some type of bioactive potential, including; soft corals (Alcyonium palmatum); tunicates (Ascidia mentula); bony fish, such as horse mackerel (Trachurus trachurus); European hake (Merluccius merluccius); and chondrichthyans, such as small-spotted catshark (Scyliorhinus canicula). In addition, 16% of the discarded species had congeneric species that produce compounds with bioactive potential, indicating that such species might also possess similar types of bioactive molecules. Molecules with antioxidant, antitumour, antihypertensive, and antibacterial properties were the most frequent, which could provide the basis for future research aiming to discover new marine-based drugs and compounds for other human uses. Among all species or genera that produce compounds with bioactive potential, 68% presented medium or high vulnerability to trawling. Results show that the discarded catch contains many species, which produce different bioactive compounds that represent an added-value resource. These results highlight the importance of manage properly crinoid beds, to ensure that species that produce molecules with bioactive potential inhabiting these habitats are protected.  相似文献   
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–  • We combined stem volume increment analysis with dendroecological tools to address two unresolved issues concerning oak dieback in Mediterranean areas: early detection of changes in stand growth, and identification of mechanisms for observed growth declines.  相似文献   
4.
Soil available water capacity (AWC) is an important factor affecting soil productivity in semiarid and subhumid environments and is mainly determined by the soil textural composition. As the soils of these environments usually present fairly uniform textures across depth, we hypothesized that it would be possible to accurately estimate the whole-profile AWC using surface information. Our objective was to test this hypothesis in the Argentine Semiarid Pampas. Information was collected from 152 sites where AWC was measured in 20?cm layers up to a depth of 140?cm or up to the upper limit of the petrocalcic horizon, when present. In each case, whole profile AWC was estimated using a one-step and a two-step approach, comparing multiple regression and artificial neural networks as modeling techniques. Both modeling methods were effective (R2?>?0.76, P?相似文献   
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Adrenomedullin (AM) has been characterized as an endogenous tissue survival factor and modulator of many inflammatory processes. Because of the increased susceptibility of the mammary gland to infection during the time surrounding parturition in the cow, we investigated how milk and tissue content of AM and its binding protein (AM-BP) might be affected by the stage of lactation and the udder health status. Milk and mammary biopsy samples were obtained from Holstein cows 21 days prior to and at various times after calving to represent the dry period and early and mid-stages of lactation. Additional cows received an intramammary challenge with Escherichia coli for immunohistochemical characterization of AM and AM-BP. Milk AM concentrations were relatively constant across the stages of lactation while AM-BP increased two-fold (P<0.04) between early and mid-lactation. Milk AM (P<0.04) and AM-BP (P<0.03) increased as somatic cell counts (SCCs) increased within a given stage of lactation. Tissue content of both (AM and AM-BP) were significantly affected by stage of lactation, lowest in the dry period and progressively increasing to peak at mid-lactation as well as increasing in association with higher levels of SCCs. Following E. coli challenge, AM increased in epithelial cells surrounding mammary alveoli presenting high levels of SCCs. The data suggest that AM and AM-BP are cooperatively regulated in the mammary gland during lactation; changes in localized tissue AM and AM-BP content reflect a dynamic regulation of these tissue factors in the bovine mammary gland consistent with their protective effects within inflamed tissue.  相似文献   
7.
The present work describes the microtomographic characterization of macro‐ and microcalcifications present in excised canine mammary glands. In human breast cancer, microcalcifications are highly relevant for diagnosis and prognosis, often being the sole element determining biopsy. Canine mammary tumours are considered a model for human breast cancer, but the morphological features of calcifications had still to be studied in this species. The objective of this research is to contribute to the characterization of the mineralization features of the canine mammary gland. In the present study, the excised mammary glands of 33 bitches underwent fluoroscopic examination. In 30 of the samples, the presence of calcification was suspected, and multiple biopsies were taken of these areas. Biopsy fragments underwent microtomographic scanning. Microcalcifications were found in non‐neoplastic glandular tissue, benign and malign lesions, as it is known to happen in humans. Qualitative evaluation regarding morphology of the imaged calcifications showed similarities to breast cancer findings, based on the BI‐RADS 2013 classification, such as pleomorphism and shape. No differences in the quantitative morphological parameters of volume, surface, surface/volume, SMI and structure thickness were found when macrocalcifications were considered. However, although significant differences existed in these parameters between microcalcifications from malignant canine mammary tumours and the two other groups, none were found between non‐neoplastic and benign tumours. Findings further support the use of this spontaneous animal model for the study of human breast cancer, considering how clinically relevant microcalcifications are in humans.  相似文献   
8.

Context

Multi-scale approaches to habitat modeling have been shown to provide more accurate understanding and predictions of species-habitat associations. It remains however unexplored how spatial and temporal variations in habitat use may affect multi-scale habitat modeling.

Objectives

We aimed at assessing how seasonal and temporal differences in species habitat use and distribution impact operational scales, variable influence, habitat suitability spatial patterns, and performance of multi-scale models.

Methods

We evaluated the environmental factors driving brown bear habitat relationships in the Cantabrian Range (Spain) based on species presence records (ground observations) for the period 2000–2010, LiDAR data on forest structure, and seasonal estimates of foraging resources. We separately developed multi-scale habitat models for (i) each season (spring, summer, fall and winter) (ii) two sub-periods with different population status: 2000–2004 (with brown bear distribution restricted to the main population nuclei) and 2005–2010 (with expanding bear population and range); and (iii) the entire 2000–2010 period.

Results

Scales of effect remained considerably stable across seasonal and temporal variations, but not the influence of certain environmental variables. The predictive ability of multi-scale models was lower in the seasons or periods in which populations used larger areas and a broader variety of environmental conditions. Seasonal estimates of foraging resources, together with LiDAR data, appeared to improve the performance of multi-scale habitat models.

Conclusions

We highlight that the understanding of multi-scale behavioral responses of species to spatial patterns that continually shift over time may be essential to unravel habitat relationships and produce reliable estimates of species distributions.
  相似文献   
9.
The virulence of two wild type (PA45 and PA37) and two genetically modified (13C: hygromycin resistant; FATSS: hygromycin resistant and β-cin knock-down) Phytophthora cinnamomi strains towards cork oak (Quercus suber) was assessed via a quantitative evaluation of disease symptoms arising from a soil infestation assay, and by a histological analysis of root colonization. Comparison of virulence, as expressed by symptom severity, resulted in the following ranking: highly virulent (wild type strains), medium virulence (strain 13C) and weakly virulent (FATSS). Both transgenic strains were compromised in their virulence, as expressed by symptom severity, but strain 13C was much less affected than FATSS. Microscopic observation showed that the FATSS strain was unable to effectively invade the root, while 13C and the two wild type strains were all able to rapidly colonize the whole root, including the vascular tissue. These results strengthen the notion that elicitins are associated, either directly or indirectly, with the infection process of Phytophthora.  相似文献   
10.
Response of western flower thrips, Frankliniella occidentalis (Pergande), to selection for resistance to insecticides commonly used to control this pest in Murcia (south-east Spain) was studied under field and laboratory conditions. In the field, plots within sweet pepper crops in commercial and experimental greenhouses were treated under different selection strategies: insecticide rotation versus formetanate reiteration, formetanate reiteration versus acrinathrin reiteration, and formetanate reiteration versus methiocarb reiteration. Thrips populations were sampled monthly and bioassayed against methiocarb, methamidophos, acrinathrin, endosulfan, deltamethrin and formetanate. In the laboratory, F occidentalis strains were selected against each insecticide for several generations. To evaluate cross-resistance, each selected strain was bioassayed with the other insecticides. Frankliniella occidentalis populations showed a rapid development of acrinathrin resistance, reaching high levels in field and laboratory conditions. Formetanate and methiocarb resistance were also observed, although development was slower and at moderate levels. Cross-resistances between acrinathrin/deltamethrin and acrinathrin/formetanate were detected under field and laboratory conditions. Formetanate/methiocarb cross-resistance was suspected in laboratory selections, but not in field assays. Simultaneous moderate resistance levels to the three specific insecticides against thrips (formetanate, methiocarb and acrinathrin) were shown in laboratory selection strains, indicating a general mechanism of resistance, probably metabolic.  相似文献   
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