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51.
Aursand IG Gallart-Jornet L Erikson U Axelson DE Rustad T 《Journal of agricultural and food chemistry》2008,56(15):6252-6260
Low-field (LF) (1)H NMR T 2 relaxation measurements were used to study changes in water distribution in lean (Atlantic cod) and fatty (Atlantic salmon) fish during salting in 15% NaCl and 25% NaCl brines. The NMR data were treated by PCA, continuous distribution analysis, and biexponential fitting and compared with physicochemical data. Two main water pools were observed in unsalted fish, T 21, with relaxation times in the range 20-100 ms, and T 22, with relaxation times in the range 100-300 ms. Pronounced changes in T 2 relaxation data were observed during salting, revealing changes in the water properties. Salting in 15% brine lead to a shift toward longer relaxation times, reflecting increased water mobility, whereas, salting in saturated brines had the opposite effect. Water mobility changes were observed earlier in the salting process for cod compared to salmon. Good linear correlations ( F = 0.05) were found between T 2 parameters and water holding capacity, centrifugation loss, water activity, and salt content in the liquid phase for all fish groups. Fillet pH and total weight changes correlated linearly with T 2 parameters for some of the fish groups. 相似文献
52.
Lorena de la Torre Parra Apisalome Movono Regina Scheyvens Sophie Auckram 《Asia Pacific viewpoint》2023,64(2):222-238
The aim of this paper is to discuss how community relational economic practices in virtual spaces are effective in building resilience because they are borne of and sustained by familiar traditional Fijian values of collective work and social interdependence. The researchers adopted a pandemic-induced methodology, conducting online-based talanoa (fluid conversations between two or more people) with a number of people leading, or involved in, these initiatives. We also engaged with online community groups behind a number of initiatives. Examples are provided of online crowdfunding, livestreaming of concerts to solicit donations, and bartering facilitated by social media sites. To conclude, we stress the enduring nature of communal bonds and traditional systems which Pacific people readily adapt and translate into different forums and forms in the face of challenges such as the restrictions and financial hardships caused by COVID-19. The findings highlight that solesolevaki – a tradition of working together for a common cause – can also occur in the digital era: this demonstrates the deep connection of Fijian peoples and their sense of obligation to one another and to their culture, regardless of where they are in the world. 相似文献
53.
54.
Relationships between rock fragment cover and soil hydrological response in a Mediterranean environment 总被引:1,自引:0,他引:1
Lorena M. ZAVALA Antonio JORDÁN Nicolás BELLINFANTE Juan GIL 《Soil Science and Plant Nutrition》2010,56(1):95-104
Rock fragments are a key factor for determining erosion rates, particularly in arid and semiarid environments where vegetation cover is very low. However, the effect of rock fragments in non-cultivated bare soils is still not well understood. Currently, there is a need for quantitative information on the effects of rock fragments on hydrological soil processes, in order to improve soil erosion models. The main objective of the present research was to study the influence of rock fragment cover on run-off and interrill soil erosion under simulated rainfall in Mediterranean bare soils in south-western Spain. Thirty-six rainfall simulation experiments were carried out at an intensity of 26.8 mm h−1 over 60 min under three different classes of rock fragment cover (<50%, 50–60% and >60%). Ponding and run-off flow were delayed in soils with high rock fragment cover. In addition, sediment yield and soil erosion rates were higher in soils with a low rock fragment cover. The relationship between soil loss rate and rock fragment cover was described by an exponential function. After this first set of experiments, rock fragments were removed from sites with the highest cover (>60%) and the rainfall simulation experiments were repeated. The steady-state run-off rate and soil loss increased significantly, showing that run-off and soil erosion were partly conditioned by rock fragment cover. These results have significant implications for erosion modelling and soil conservation practices in areas with the same climate and soil characteristics. 相似文献
55.
The compensatory growth response of the Atlantic cod: effects of nutritional history 总被引:30,自引:0,他引:30
The effects of different combinations of nutritional background, feeding regimes and dietary compositions on growth responses of the Atlantic cod have been examined. Alternating short periods (1–3 weeks) of food deprivation with unlimited provision of food depressed growth below that of controls, but cod that were fed on alternate weeks (1:1) were larger than those that were exposed to 2 or 3 week periods of deprivation and feeding (2:2 or 3:3). Thus, periods of food deprivation of short duration were insufficient to induce any marked compensatory growth response. When cod were deprived of food for longer periods a compensatory growth response was observed. On receiving excess food supplies following 8 weeks of food deprivation the fish grew more rapidly than the controls and had completely recovered body weight within 12 weeks. The greatest compensatory growth response was shown by cod in poor condition (lowest condition factor), because at the end of an 18 week growth trial there were no differences in body weight between fish irrespective of their initial condition. Both sexes displayed a compensatory growth response. 相似文献
56.
M. Gajda J. A. Litwin O. Zagólski G. J. Lis T. Cichocki J.-P. Timmermans D. Adriaensen 《Anatomia, histologia, embryologia》2009,38(2):112-117
Galanin exerts tonic inhibition of nociceptive input to the central nervous system. Recently, this peptide was demonstrated in several neuronal and non-neuronal structures in bones and joints. In this study, the time of appearance and topographic localization of galanin-containing nerve fibres in bone were studied in rats from gestational day 16 (GD16) to postnatal day 21 (PD21). The tibia was chosen as a model of developing long bone and indirect immunofluorescence combined with confocal laser scanning microscopy was used to identify galanin-immunoreactive (GAL-IR) nerve fibres. The earliest, sparse GAL-IR fibres were observed on GD21 in the perichondrium of both epiphyses and in the periosteum of the diaphysis. From PD1 onwards, GAL-IR fibres were also seen in the bone marrow cavity and in the region of the inter-condylar eminence of the knee joint. Intramedullary GAL-IR fibres in proximal and distal metaphyses appeared around PD1. Some of them accompanied blood vessels, although free fibres were also seen. GAL-IR fibres located in the cartilage canals of both epiphyses were observed from PD7, in the secondary ossification centres from PD10 and in the bone marrow of both epiphyses from PD14. The time course and localization of galanin-containing nerve fibres resemble the development of substance P- and CGRP-expressing nerve fibres, thus suggesting their sensory origin. 相似文献
57.
Berendt M Gredal H Pedersen LG Alban L Alving J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(3):262-268
The purpose of this study was to investigate the prevalence and selected risk factors of epilepsy, the proportion of dogs with epilepsy in remission, and the types of seizures in Danish Labrador Retrievers. A prospective cross-sectional study of epilepsy was conducted in 1999-2000. The study was carried out in 2 phases in a reference population consisting of 29,602 individuals. In phase 1, 550 dogs were selected by random sampling stratified by year of birth. A telephone interview was used to identify dogs with possible epilepsy. In phase 2, dogs judged during phase 1 as possibly suffering from epilepsy were further subjected to physical and neurologic examination, CBC, blood chemistry, and a questionnaire on seizure phenomenology. Seventeen dogs were diagnosed with epilepsy, yielding a prevalence of 3.1% (95% CI 1.6-4.6%) in the Danish population of Labrador Retrievers. A diagnosis of epilepsy was 6 times more probable in dogs >4 years (born before 1995) than in younger dogs (born between 1995 and 1999) (P = .004, relative risk = 6.5). No significant difference in risk between genders was observed, nor could any effect of neutering be proven statistically. The frequencies of primary generalized seizures and partial seizures (with or without secondary generalization) were 24 and 70%, respectively. The type of seizures could not be classified in 6%. In conclusion, the 3.1% prevalence of epilepsy in Danish Labrador Retrievers is higher than the 1% prevalence of epilepsy described in the general canine population, establishing that this breed is at increased risk. 相似文献
58.
There has long been a focus in urban landscape planning and design on the creation of highquality public spaces, or place-making. Large amounts of capital continue to be spent on creating such spaces without adequate thought or resources for their long-term maintenance and management of public spaces, or place-keeping.While there may be continued policy rhetoric about the importance of place-keeping, particularly as public spaces are recognised for their important contribution to health, wellbeing, biodiversity and also their economic value, this has not however been supported in practice. There are examples in many cities where public spaces are subject to poor management and maintenance practices. This is clearly visible where vandalism, litter and damage to facilities and equipment occur, and people no longer feel safe or comfortable.This paper argues that this uneven focus on place-keeping is not only due to a lack of resources but also a lack of understanding of the concept, its complexity and the wide implications it has for users, practitioners and policymakers. The paper aims to address this gap in knowledge by providing a detailed exploration and definition of place-keeping within the urban context. Place-keeping is not simply about the physical environment, its design and maintenance, but also encompasses the interrelated and non-physical dimensions of partnerships, governance, funding, policy and evaluation. 相似文献
59.
Integrating stakeholders’ demands and scientific knowledge on ecosystem services in landscape planning 总被引:1,自引:0,他引:1
Igone Palacios-Agundez Beatriz Fernández de Manuel Gloria Rodríguez-Loinaz Lorena Peña Ibone Ametzaga-Arregi Josu G. Alday Izaskun Casado-Arzuaga Iosu Madariaga Xabier Arana Miren Onaindia 《Landscape Ecology》2014,29(8):1423-1433
The conflict between conservation and timber production is shifting in regions such as Biscay (Basque Country, northern Spain) where planted forests are no longer profitable without public subsidies and environmentalist claim that public subsidies should be reoriented to the regeneration of natural forest. This paper develops an approach that integrates scientific knowledge and stakeholders’ demands to provide decision-making guidelines for the development of new landscape planning strategies while considering ecosystem services. First, a participatory process was conducted to develop a community vision for the region’s sustainable future considering the opportunities and constrains provided by the landscape and its ecosystems. In the participatory process forest management was considered an important driver for the region`s landscape development and forest multi-functionality was envisioned as a feasible attractive alternative. The participatory process identified a knowledge gap on the synergies and trade-offs between biodiversity and carbon storage and how these depend on different forest types. Second, to study the existing synergies and trade-offs between biodiversity and carbon storage and disentangle the identified knowledge gap, a GIS-based research was conducted based on spatially explicit indicators. Our spatial analysis results showed that natural forests’ contribution to biodiversity and carbon storage is higher than that of the plantations with exotic species in the region. The results from the spatial analysis converged with those from the participatory process in the suitability of promoting, where possible and appropriate, natural forest ecosystems restoration. This iterative learning and decision making process is already showing its effectiveness for decision making, with concrete examples of how the results obtained with the applied approach are being included in planning and decision-making processes. 相似文献
60.