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251.
Martínez-Vilalta J Mangirón M Ogaya R Sauret M Serrano L Peñuelas J Piñol J 《Tree physiology》2003,23(11):747-758
We studied the seasonal patterns of water use in three woody species co-occurring in a holm oak forest in northeastern Spain. The three species studied, Quercus ilex L., Phillyrea latifolia L. and Arbutus unedo L., constitute more than 99% of the total basal area of the forest. The study period included the dry seasons of 1999 and 2000. Water use was estimated with Granier-type sap flux sensors. Standard meteorological variables, soil water content and leaf water potentials were also monitored. All monitored individuals reduced leaf-related sap flow (Q(l)) during the summer, concurrent with an increase in soil moisture deficit (SMD). Despite similar maximum Q(l) between species, the decline in Q(l) with increasing SMD was species-dependent. The average reduction in Q(l) between early summer and the peak of the drought was 74% for A. unedo (n = 3), 58% for P. latifolia (n = 3) and 87% for Q. ilex (n = 1). The relationship between canopy stomatal conductance (G(s)) and vapor pressure deficit (D) changed during the course of the drought, with progressively lower G(s) for any given D. Summertime reductions of Q(l) and G(s) were associated with between-species differences in vulnerability to xylem embolism, and with the corresponding degree of native embolism (lowest in P. latifolia and highest in Q. ilex). Our results, combined with previous studies in the same area, outlined differences among the species studied in manner of responding to water shortage, with P. latifolia able to maintain water transport at much lower water potentials than the other two species. In an accompanying experiment, A. unedo responded to an experimental reduction in water availability by reducing Q(l) during the summer. This species also modified its water use between years according to the different seasonal patterns of precipitation. These results are discussed in relation to the possible impacts that climate change will have on Q. ilex-dominated forests. 相似文献
252.
Marta Planellas Rafaela Cuenca Maria-Dolores Tabar Coralie Bertolani Cyrill Poncet Josep M. Closa Juan Lorente José J. Cerón Josep Pastor 《Canadian journal of veterinary research》2015,79(1):58-63
Brachycephalic dogs have unique upper respiratory anatomy with abnormal breathing patterns that are similar to those in humans with obstructive sleep apnea syndrome (OSAS). The objectives of this multicenter prospective study were to assess the effects of surgical correction on clinical signs in dogs with brachycephalic airway obstructive syndrome (BAOS) and to evaluate the levels of several biomarkers [C-reactive protein (CRP); haptoglobin (Hp), and cardiac troponin I (cTnI)] used to determine systemic inflammation and myocardial damage. This study was conducted on 33 dogs with BAOS that were evaluated before and 1 to 2 mo after surgical correction. Palatoplasty was carried out by means of 2 different surgical techniques: carbon dioxide (CO2) laser (n = 12) and electrical scalpel (n = 21). Biomarker levels (CRP, Hp, and cTnI) were determined before and after surgery. There was a significant reduction in respiratory and gastrointestinal signs in dogs with BAOS after surgical treatment (P < 0.001). A greater reduction in respiratory signs (P < 0.002) was obtained using the CO2 laser. No statistical differences were found between CRP and cTnI levels, either before or after surgical correction. Haptoglobin concentration did increase significantly in the postsurgical period (P < 0.008). Surgical treatment in dogs with BAOS reduces clinical signs, regardless of the anatomical components present. Surgical treatment for BAOS is not useful to reduce CRP and Hp levels, probably because BAOS does not induce as obvious an inflammatory process in dogs as in human patients with OSAS. No reduction in cTnI levels was observed 1 mo after surgery in dogs with BAOS, which suggests that some degree of myocardial damage remains. 相似文献
253.
Josep‐Maria Arauzo‐Carod 《Growth and change》2013,44(1):118-148
This paper is about the role played by the stock of human capital on location decisions of new manufacturing plants. I analyse the effect of several skill levels (from basic school to PhD) on decisions about the location of plants in various industries and, therefore, of different technological levels. I also test whether spatial aggregation level biases the results and determines the most appropriate areas to be considered in the analyses of these phenomena. My main statistical source is the Register of Manufacturing Establishments of Catalonia, which has plant‐level microdata on the locations of new manufacturing plants. 相似文献
254.
A three-year field experiment (2006–2008) on clingstone peach cv. Andross was conducted in a commercial orchard under mechanical
harvesting for the processing industry. Three irrigation strategies were evaluated: full irrigation throughout the growing
season; restricted irrigation during stage-II (~70% restriction) and restricted irrigation during stage-III (~30% restriction),
combined with three nitrogen fertilization treatments: 0, 60 and 120 kg N/ha. Trees were fertigated on a daily basis. Daily
patterns of soil moisture were monitored with capacitance probes. Irrigation restriction strategies and nitrogen dose affected
yield and fruit quality at commercial harvest. As well as the individual effects of applying irrigation strategies and N doses,
interactions between the two factors were analyzed. In the second year, there was a nitrogen × irrigation interaction for
fruit yield. A positive yield effect for N applied to fully irrigated trees occured, while the opposite was observed when
the irrigation restrictions were applied during stage-III. 相似文献
255.
Yonvitner Yonvitner Josep LIoret Mennofatria Boer Rahmat Kurnia Surya Gentha Akmal Ernik Yuliana Diarsi Eka Yani Sílvia Gmez Ludivica Endang Setijorini 《Fisheries Management and Ecology》2020,27(5):472-480
Although small‐scale fisheries (SSF) play an important socio‐economic role in developing nations, overfishing seems to be increasing the risk of stock vulnerability. This study aims to quantify the pressure of SSF on fish stocks in Sunda Strait (Indonesia) using several biological indicators that are important in quantifying fishing pressure. Data on these indicators were collected monthly for three years (2012–2014) in one of the main fishing ports of the area. The results provide evidence that, although SSF would appear to be the most environmentally sustainable of all the fishing techniques being used today in the coastal waters of Indonesia, the impact of SSF fishing on juvenile fishes in certain areas such as the Sunda Strait must not be underestimated. The results also show the need to protect immature fish of species that are not only commercialised but are also important in subsistence fisheries. Although further studies are needed to assess the impact of SSF on fish stocks in the area, it is suggested management recommendations that include the implementation of marine‐protected areas in nursery grounds and establishing minimum landing sizes well above the size‐at‐maturity for each species, are needed. 相似文献
256.
Fluctuations of landings and environmental conditions in the north-western Mediterranean Sea 总被引:12,自引:1,他引:12
Josep Lloret Jordi Lleonart Ignasi Solé & Jean-Marc Fromentin 《Fisheries Oceanography》2001,10(1):33-50
Most of the monthly catches and CPUE of 13 studied commercial species in the coastal waters of the north-western Mediterranean were significantly positively correlated with run-off of local rivers (Rhône and Muga) and the wind mixing index during the spawning season, with time lags of less than a year (transfer function analyses). Rhône and Ebre interannual fluctuations in run-off were synchronous and were related to the North Atlantic Oscillation (NAO), river run-offs being negatively correlated to high NAO episodes. The fluctuations of river discharges and the wind mixing index were cyclic but not related. The results showed that enhanced hydroclimatic conditions in the NW Mediterranean were favourable for the productivity of the fish and invertebrate stocks, and suggest the presence of linkage between recruitment of Mediterranean species and local (river discharges, wind conditions) and global (NAO) environmental conditions. 相似文献
257.
258.
Rosario Torres Carla Nunes José María García Maribel Abadias Inmaculada Viñas Teresa Manso Manuel Olmo Josep Usall 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):73-83
We determined the potential of using a formulated product based on Pantoea agglomerans CPA-2, either alone or in combination with heated sodium bicarbonate (SBC) solutions, to control the major postharvest diseases
affecting citrus crops in the Mediterranean region. Treatments applied either individually or in combination were tested in
semi-commercial and commercial trials carried out with oranges and mandarins from the Algarve, Andalusia and Catalonia. Firstly,
several formulations of the biocontrol agents were tested in laboratory trials; one of them, a freeze-dried formulation of
P. agglomerans strain CPA-2 called FD10-3, was chosen for combined with SBC. This formulation, applied at 2 × 108cfu ml−1 and the SBC treatment, applied at 3% 50°C for 20–40 s, demonstrated that it was possible to reduce decay development in laboratory
trials. Semi-commercial applications of FD10-3 and 3% SBC solution at 50°C for 40 s showed excellent control of decay in unwounded
mandarins and oranges artificially inoculated with both Penicillium digitatum and P. italicum. No rind injuries or residues attributable to hot water or SBC were observed on treated fruits. Combined treatment provided
better control than the two treatments applied separately. Commercial trials demonstrated an important reduction in natural
decay with the treatment of SBC 3% at 50°C for 40 s. Furthermore, bacterial-product formulation treatment significantly reduced
the percentage of infected fruit and in some cases this reduction was equal to chemical treatments. Even so, no improvement
in efficacy was observed with the combination of FD10-3 and SBC in the commercial test. We also assessed the ability of FD10-3
to grow at the wound site in oranges, whether alone or in the presence of SBC, and also its compatibility with standard citrus
packinghouse practices. 相似文献
259.
Marta Planellas Anna Bassols Carlo Siracusa Yolanda Saco Mercè Giménez Raquel Pato Josep Pastor 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(3):348-352
Background: In veterinary medicine, there is increasing interest in measuring acute phase proteins as a tool in the diagnosis and monitoring of neoplastic diseases. Although mammary neoplasms are the most common type of cancer in dogs, acute phase proteins have not been extensively evaluated in dogs with mammary tumors. Objectives: The aim of this study was to evaluate serum haptoglobin (Hp) and C‐reactive protein (CRP) concentrations in the dogs with mammary tumors and assess their potential association with malignancy. Methods: A retrospective study of dogs with mammary tumors was performed. Serum concentrations of CRP and Hp were determined in healthy control dogs (n=20) and dogs with mammary tumors before surgery (n=41). Mammary tumors were grouped as carcinomas (n=24), fibrosarcoma (n=1), malignant mixed tumors (n=7), benign mixed tumors (n=6), and adenomas (n=3). CRP and Hp concentrations were compared in dogs with different tumor types and were also compared based on tumor size, lymph node infiltration, skin ulceration, fixation to underlying tissue, and time between tumor identification and removal. Results: Hp concentration was significantly (P<.043) higher in dogs with mammary tumors (median 2.03 g/L, range 0.09–2.94 g/L) compared with controls (1.38 g/L, range 0.08–3.00 g/L), but the range of values overlapped considerably. CRP concentration was higher in dogs with carcinomas (4.70 mg/L, range 0.63–128.96 mg/L) vs controls (2.11 mg/L, range 0.25–6.57 mg/L) (P=.0008) and in dogs with ulcerated skin (14.8 mg/L, range 5.7–128.9 mg/L, n=3) compared with those without ulceration (2.4 mg/L, range 0.11–30.3 mg/L, n=38) (P=.048). Conclusions: Serum Hp and CRP do not appear to have value in diagnosing or predicting malignancy of mammary tumors in dogs. Higher CRP concentrations in dogs with mammary carcinoma suggest a role for inflammation in this tumor type. 相似文献
260.
Xavier Domene Stefania Mattana Wilson Ramírez Joan Colón Patrícia Jiménez Teresa Balanyà Josep M. Alcañiz Manel Bonmatí 《Journal of Soils and Sediments》2010,10(1):30-44