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1.
Effects of soil water potential on stem radius changes of Norway spruce (Picea abies (L.) Karst.) The stem radius of 2 mature Norway spruce trees and the soil water potential were continuously measured in situ with dendrometers and tensiometers, respectively. In a period without growth and frost events the stem radius and the soil water potentials correlated closely. A young spruce tree grown under controlled conditions changed its radius in response to the soil water supply likewise. The shrinkage of the stem was reversible, even if the soil was very dry (soil water potential ± ? 1000 hPa). An estimate of the soil water potential seems to be possible even beyond ? 1000 hPa by measurements of stem radius changes.  相似文献   
2.
Images of the molecular CO 2-1 line emission and the radio continuum emission from the redshift 4.12 gravitationally lensed quasi-stellar object (QSO) PSS J2322+1944 reveal an Einstein ring with a diameter of 1.5". These observations are modeled as a star-forming disk surrounding the QSO nucleus with a radius of 2 kiloparsecs. The implied massive star formation rate is 900 solar masses per year. At this rate, a substantial fraction of the stars in a large elliptical galaxy could form on a dynamical time scale of 108 years. The observation of active star formation in the host galaxy of a high-redshift QSO supports the hypothesis of coeval formation of supermassive black holes and stars in spheroidal galaxies.  相似文献   
3.

Background

Salmonella species (spp.) are zoonotic enteric bacteria able to infect humans, livestock and wildlife.However, little is known about the prevalence and the presence of the different serovars in wildlife. Considering the wide distribution of wild boars and the feeding behaviour (omnivorous scavengers), wild boars may be a good indicator for environmental presence of Salmonella spp. The aims of this study were to determine the presence of Salmonella spp. in hunted wild boars and to determine the serotype the isolated strains.

Findings

Over three hunting seasons, the intestinal contents of 1,313 boars hunted in northern Italy were sampled and cultured. Salmonella spp. were isolated from 326 boars (24.82%). Thirty different serovars belonging to three different S. enterica spp. were found. Twenty-one serovars of S. enterica subsp. Enterica were found including the human pathogens S. Typhimurium and S. Enteritidis. In addition, nine serovars belonging to S.enterica subsp. diarizonae and S. enterica subsp. houtenae were detected.

Conclusions

Considering the widespread occurrence of wild boars in Europe, the epidemiological role of this species in relation to salmonellosis might be relevant and should be further investigated. Wild boars may act as healthy carriers of a wide range of Salmonella serotypes.  相似文献   
4.
This study aimed to determine the lowest effective concentration (LEC) of 2‐phenoxyethanol (2‐Phe) and essential oils (EOs) of Melaleuca alternifolia and Ocimum gratissimum able to induce anaesthesia in Astyanax bimaculatus. LEC was assumed to be the required concentration to carry out anaesthesia in less than 3 min with recovery in <5 min and sufficient to carry out routine aquaculture procedures. The following concentrations were tested: 2‐Phe (100, 200, 300, 400, 500 and 600 µl/L); M. alternifolia (200, 300, 400, 500 and 600 µl/L); and O. gratissimum (10, 20, 30, 40, 50, 60, 70, 100, 150, 250 and 300 µl/L). Results show that all three agents evaluated have effective anaesthetic properties for use in Astyanax bimaculatus with LEC for 2‐Phe, M. alternifolia and O. gratissimum of 200, 300 and 60 µl/L respectively.  相似文献   
5.
In this study, we investigated the dynamics of Mycoplasma hyopneumoniae infections in 66 pig farms, with different production systems (one-, two-, and three-site systems), and considered different risk factors. Serological assay was used to detect serum antibodies against M. hyopneumoniae and real time polymerase chain reaction (RT–PCR) was performed to detect M. hyopneumoniae DNA in tracheobronchial swabs. Results demonstrated that M. hyopneumoniae infection status was predominantly influenced by the age of the animals and the type of production system. Infection rates were higher in older animals and the prevalence was higher in the one- and two-site systems than in the three-site systems. Dynamics of infection by RT-PCR showed that earlier M. hyopneumoniae infection on one-site farms occurs earlier, while on two- and three-site farms occurs later but spreads faster, suggesting that contact between animals of different age favors the transmission.  相似文献   
6.
7.
This paper describes the accumulation pattern of 42 mineral elements in Vitis vinifera L. berries during development and ripening and their distribution in berry skin, seeds, and flesh around harvest time. Grape berries were sampled in two different vineyards with alkaline soil and analyzed using a ICP-MS. Although elemental amounts were significantly different in the grapes from the two vineyards, the accumulation pattern and percentage distribution in different parts of the berries were generally quite similar. Ba, Eu, Sr, Ca, Mg, Mn, and Zn accumulate prior to veraison. Al, Ce, Dy, Er, Ga, Gd, Ho, La, Nd, Pr, Sm, Sn, Zr, Th, Tm, U, Y, and Yb accumulate mainly prior to veraison but also during ripening. Ag, As, B, Cd, Cs, Cu, Fe, Ge, Hg, K, Li, Na, P, Rb, Sb, Se, and Tl accumulate progressively during growth and ripening. With regard to distribution, Ba, Ca, Eu, Fe, Mn, P, Sr, and Zn accumulate mainly in the seeds, Al, B, Ga, Sn, and the rare earths analyzed, except for Eu, accumulate mainly in the skin, and Ag, As, Cd, Cs, Cu, Ge, Hg, K, Li, Mg, Na, Rb, Sb, Se, Th, Tl, U, and Zr accumulate mainly in the flesh. A joint representation of the accumulation and distribution patterns for the elements in the berry is also given.  相似文献   
8.
? The feasibility of yard waste composting in a closed continuous reactor with heat recovery has been investigated. Results obtained in this research are reported and discussed. In the system, the recovered energy (heat) can be transformed by a heat pump in hot water both for domestic and for residential heating. The organic fertilizer produced can be used in horticulture.  相似文献   
9.
The aim of this work (from the FP6 project TRACE) was to develop methods based on the use of geochemical markers for the authentication of the geographical origin of cereal samples in Europe (cf. EC regulations 2081/92 and 1898/06). For the first time, the potential usefulness of combining n(87Sr)/n(86Sr) and δ13C, δ15N, δ18O and δ34S isotopic signatures, alone or with key element concentrations ([Na], [K], [Ca], [Cu] and [Rb], progressively identified out of 31 sets of results), was investigated through multiple step multivariate statistics for more than 500 cereal samples collected over 2 years from 17 sampling sites across Europe representing an extensive range of geographical and environmental characteristics.  相似文献   
10.
BackgroundAntibiotic‐responsive enteropathy (ARE) is diagnosed by excluding other causes of diarrhea and when there is a short‐term response to administration of antibiotics.ObjectivesTo characterize the gut microbiota and clinical trend of dogs with suspected ARE and to evaluate the variation in microbiota before (T0), after 30 days (T30) of tylosin treatment, and 30 days after discontinuation of treatment (T60). A further objective was to evaluate whether changes in gut microbiota are related to relapses of diarrhea when the therapy is tapered.AnimalsStudy sample (group A) was composed of 15 dogs with chronic diarrhea, group B was composed of 15 healthy dogs. Group A was given tylosin for 30 days.MethodsA multicentric prospective study. Clinical Indexes, fecal score, and samples for microbiota analysis were collected at T0, T30, and T60 in group A and T0 and T30 in group B. The gut microbiota was analyzed via 16S ribosomal RNA gene. Qiime2 version 2020.2 was used to perform bioinformatic analyses, and Alpha‐ and Beta‐diversity were computed.ResultsDiarrhea recurred after T30 in 9 of 14 dogs, which were classified as affected by ARE. At T0, a difference was noted in the beta‐diversity between groups (Bray Curtis metric P = .006). A T0‐T30 difference in alpha‐diversity was noted in group A (Shannon index P = .001, Faith PD P = .007).Conclusions and Clinical ImportanceAlthough tylosin influences the microbiota of dogs with ARE, we failed to find any specific characteristic in the microbiota of dogs with ARE.  相似文献   
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