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71.
Complex agroforestry systems that mimic local forest structure, so-called ‘analogs’, are assumed to be of specific value to rural people as well as the environment. The objective of this study was to document and evaluate the utilization of plant resources by Philippine lowland farmers to identify native species suitable for integration in such a system. The interviewed farmers maintain a comprehensive ethnobotanical knowledge. They reported using 122 plant species for 77 purposes. Eighty species have medicinal value, 35 provide food, and 32 serve other uses. About 64% of the identified species are Philippine natives. The life form composition of these species is dominated by trees but also includes herbs, lianas, and graminoids, thus providing the structural elements required in analog systems. Nevertheless, only a few of the species seem to be promising for cultivation. Many of them are ubiquitous in the vicinity of villages. Some species are also not much appreciated but act as staple food only during food shortage. Even though several of the species have proven market value, such as rattan (e.g. Calamus merrillii), or are reputed medicines, such as ‘Philippine ginseng’ (Sarcandra glabra), no cultivation could be observed. This shows that usefulness in itself cannot be the only criterion to promote species but that it requires a careful analysis of the marketability of the respective species. In this context we suggest the following three species that are of proven medicinal value for in-depth study: the liana Tinospora crispa (Menispermaceae), the tree Picrasma javanica (Simaroubaceae), and the herb Sarcandra glabra (Chloranthaceae). They represent three different life form strategies and would thus fit well in vertically structured agroforestry systems.  相似文献   
72.
Phenology and female cone characteristics of the two endemic cedars (Juniperus cedrus and J. brevifolia) from the Macaronesian islands were studied. Despite their closely taxonomic affinity and their evolution under insular conditions, different trends were recorded. Mature J. cedrus female cones were present throughout the year, while those from J. brevifolia were only present in summer and autumn. J. cedrus female cone size was significantly larger than that of J. brevifolia, a trend consistent with the presence of larger vertebrates (lizards and birds) in the Canary Islands. However, water content was four times higher in J. brevifolia female cones, which can be related with the higher rainfall existing in the Azores. J. cedrus has two or three seeds per cone, whereas J. brevifolia frequently had three. Seeds from J. cedrus were clearly larger and heavier, coinciding with the female cone size trend. However, tetrazolium tests revealed higher viability values in J. brevifolia. The relatively low percentage of filled seeds in J. cedrus could be a consequence of the climatic stress and limits to pollination due to fragmented populations as described for other Juniperus species. In summary, our results reveal that some environmental factors such as the harsh conditions, high population fragmentation and the dependence on large dispersers have compromised the fitness of J. cedrus in the Canary Islands.  相似文献   
73.
ABSTRACT

The effects of different egg white protein coatings on Atlantic salmon quality preservation after 4 months of frozen storage were evaluated. These coatings increased the yield of the fillets and protected them from lipid oxidation, providing better protection than glazing. Egg white protein coatings were better options than glazing to preserve salmon color during frozen storage. The best results were obtained with the application of coatings before freezing. No clear effects of the type and concentration of plasticizer in most quality parameters were found. Egg white protein + glycerol 2:1 applied before freezing was the best coating for frozen Atlantic salmon protection.  相似文献   
74.

Objective

To assess the cardiopulmonary effects caused by reverse Trendelenburg position (RTP) at 5° and 10° in sevoflurane-anesthetized yearling steers.

Study design

Prospective, experimental study.

Animals

Eight Holstein steers aged (mean ± standard deviation) 12 ± 2 months and weighing 145 ± 26 kg.

Methods

In the first phase of the study, the individual minimum alveolar concentration (MAC) of sevoflurane was determined using electrical stimulation. In the second phase, the effects of RTP were assessed. The animals were anesthetized on three separate events separated by ≥7 days in an incomplete crossover design: control treatment using a table without tilt (RTP0); treatment with the table at 5° RTP (RTP5) and table tilted 10° RTP (RTP10). Subjects were physically restrained in dorsal recumbency on the table, which was already tilted according to each treatment. Anesthesia was induced with sevoflurane at 8% in 5 L minute–1 oxygen via face mask followed by maintenance with sevoflurane at 1.3 MAC and spontaneous breathing. Cardiopulmonary variables were obtained immediately after instrumentation (T0) and then after 30, 60, 120 and 180 minutes (T30, T60, T120 and T180, respectively).

Results

The mean sevoflurane MAC for the eight steers was 2.12 ± 0.31%. Cardiac output was lower at all time points and the systemic vascular resistance index was higher at T120 and T180 in RTP10 compared with RTP0. Oxygen consumption was lower at T0 and at T180 in RTP10 compared with RTP0 and at all time points except T30 compared with RTP5. Oxygen extraction was lower at T0 in RTP10 compared with RTP0 and RTP5, and at T60 and T180 compared with RTP5.

Conclusions and clinical relevance

RTP 5° and 10° did not improve ventilatory and oxygenation variables in sevoflurane-anesthetized steers when compared with no tilt, however the cardiovascular variables were adversely affected in RTP10.  相似文献   
75.

Objectives

To validate a thermal threshold (TT) nociceptive model in bearded dragons (Pogona vitticeps) and to document TT changes after administration of morphine.

Study design

A two-part randomized, blinded, controlled, experimental study.

Animals

Five adult bearded dragons (242–396 g).

Methods

A TT device delivered a ramped nociceptive stimulus (0.6 °C second?1) to the medial thigh until a response (leg kick/escape behavior) was observed or maximum (cut-off) temperature of 62 °C was reached. In phase I, period 1, six TT readings were determined at 20 minute intervals for evaluation of repeatability. Two of these readings were randomly assigned to be sham to assess specificity of the behavioral response. The same experiment was repeated 2 weeks later (period 2) to test reproducibility. In phase II, animals were administered either intramuscular morphine (10 mg kg?1) or saline 0.9%. TTs (maximum 68 °C) were determined before and 2, 4, 8, 12 and 24 hours after treatment administration. Data were analyzed using one-way anova (temporal changes and repeatability) and paired t tests (reproducibility and treatment comparisons) using Bonferroni correction (p < 0.05).

Results

Mean TT values were 57.4 ± 3.8 °C and 57.3 ± 4.3 °C for periods 1 and 2, respectively. Data were repeatable within each period (p = 0.83 and p = 0.07, respectively). Reproducibility between periods was remarkable (p = 0.86). False-positive responses during sham testing were 10%. TTs were significantly increased after morphine administration at 2, 4 and 8 hours compared with baseline, and at 2 and 4 hours compared with saline 0.9%. The highest TT was 67.7 ± 0.7 °C at 4 hours after morphine administration.

Conclusions and clinical relevance

Testing was repeatable, reproducible and well tolerated in bearded dragons. TT nociceptive testing detected morphine administration and may be suitable for studying opioid regimens in bearded dragons.  相似文献   
76.
Highly pathogenic avian influenza (HPAI) subtype H5N1 remains an enzootic disease of village chickens in Indonesia, posing ongoing risk at the animal–human interface. Previous modelling showed that the fast natural turnover of chicken populations might undermine herd immunity after vaccination, although actual details of how this effect applies to Indonesia's village chicken population have not been determined. We explored the turnover effect in Indonesia's scavenging and mixed populations of village chickens using an extended Leslie matrix model parameterized with data collected from village chicken flocks in Java region, Indonesia. Population dynamics were simulated for 208 weeks; the turnover effect was simulated for 16 weeks after vaccination in two ‘best case’ scenarios, where the whole population (scenario 1), or birds aged over 14 days (scenario 2), were vaccinated. We found that the scavenging and mixed populations have different productive traits. When steady‐state dynamics are reached, both populations are dominated by females (54.5%), and ‘growers’ and ‘chicks’ represent the most abundant age stages with 39% and 38% in the scavenging, and 60% and 25% in the mixed population, respectively. Simulations showed that the population turnover might reduce the herd immunity below the critical threshold that prevents the re‐emergence of HPAI H5N1 4–8 weeks (scavenging) and 6–9 weeks (mixed population) after vaccination in scenario 1, and 2–6 weeks (scavenging) and 4–7 weeks (mixed population) after vaccination in scenario 2. In conclusion, we found that Indonesia's village chicken population does not have a unique underlying population dynamic and therefore, different turnover effects on herd immunity may be expected after vaccination; nonetheless, our simulations carried out in best case scenarios highlight the limitations of current vaccine technologies to control HPAI H5N1. This suggests that the improvements and complementary strategies are necessary and must be explored.  相似文献   
77.
6α,7β-Dihydroxyvouacapan-17β-oic acid (1) and methyl 6α,7β-dihydroxyvouacapan-17β-oate (8) were isolated from Pterodon polygalaeflorus Benth. 1 was modified to obtain 6α-hydroxyvouacapan-7-β,17β lactone (2). Then, 6-oxovouacapan-7β,17β lactone (3) was obtained from 2. The furanoditerpene ester derivatives: propyl 7β-hydroxy-6-oxovouacapan-17β-oate (4), butyl 7β-hydroxy-6-oxovouacapan-17β-oate (5), 2-methoxyethyl 7β-hydroxy-6-oxovouacapan-17β-oate (6) and 3-methylbut-2-enyl 7β-hydroxy-6-oxovouacapan-17β-oate (7) were synthesized from (3) and methyl 6α,7β-thiocarbonyldioxyvouacapan-17β-oate (9) was obtained from (8). In this work, the lactone ester derivatives 4-7 and 9 were tested on photosynthetic activities in an attempt to search for new compounds as potential herbicide agents that affect photosynthesis. All compounds inhibited ATP synthesis and electron flow from water to MV, therefore, they act as Hill reaction inhibitors, being 4- to 9-fold more potent than 2 and 3 as inhibitors of ATP synthesis. Their interaction site was located at PSII in a similar way to diuron. Furthermore, furanoditerpene esters 6 and 7 act as uncouplers, and were corroborated by enhancement of the light-activated Mg2+-ATPase, while 5 act as an energy transfer inhibitor. Finally 5-7 behave as herbicides, since they inhibit the biomass production of weeds assay.  相似文献   
78.
Cryopreservation of selected genotypes of European chestnut and cork oak was carried out in two laboratories in a project involving conservation of field collections. Plant material was selected on the basis of disease resistance (chestnut), growth habit, phytosanitary performance and cork quality (cork oak). The cryopreservation technique comprised of vitrification of shoot apices isolated from in vitro stock shoot cultures (chestnut) and somatic embryos (cork oak). Forty-three out of 46 chestnut genotypes assayed survived the freezing process, but only 63% recovered their capacity to produce new shoots. After completion of multiplication and rooting steps, the surviving shoots produced plants that were morphologically identical to those derived from non-supercooled material. All 51 cork oak genotypes withstood freezing and were able to produce new somatic embryos through a process of secondary embryogenesis. Multiplication and germination of the recovered embryos enabled production of plants that were morphologically identical to those derived from non-supercooled material. In light of the results obtained, long-term cryopreservation of these species is feasible, thereby ensuring conservation of valuable genotypes during field evaluation.  相似文献   
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80.
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