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41.

Purpose

This paper investigates soils and sediments from the eastern Padanian Plain (northern Italy) in order to delineate the physiographic evolution of the area.

Materials and methods

We present new geochemical, mineralogical and textural analyses of alluvial sediments collected from a 13-m-deep section located a few kilometres south of Ferrara. The chronology of the related depositional events is provided from 14C dating of tree trunks buried at depths of ca. 9 m and organic matter from the underlying horizons.

Results and discussion

The data indicate that (1) the upper part of the sequence (down to depths of 9 m) includes sediments characterized by low nickel–chromium (Ni–Cr) concentrations ascribed to the alluvial deposits of the river Reno, deposited in the last 400 years; (2) buried soils (depths of 9–10.5 m) developed on Ni–Cr-rich sediments related to the river Po; and (3) the deeper facies (depths of 10.5–13 m) are CaCO3-free and characterized by higher amounts of organic carbon, sulphur and arsenic, reflecting episodic lacustrine/marsh environments. These wetlands probably developed in the area during the Iron and Roman ages, persisting up to the Middle Ages.

Conclusions

The data provide a contribution to the understanding of the evolution of the river network during the last 3,000 years and provide insights on the related paleohydrological framework that can be useful for geographical and historical reconstructions of the area. Results highlight the importance of investigating alluvial sediments to elucidate (1) fluctuations of environmental conditions and (2) anthropogenic impacts on the natural landscape.  相似文献   
42.

Objective

To describe the anaesthetic, physiological and side effects of intramuscular (IM) medetomidine and ketamine, followed by inhalational anaesthesia with sevoflurane, in Nile crocodiles (Crocodylus niloticus).

Study design

Observational trial.

Animals

Ten juvenile captive-bred Nile crocodiles undergoing surgical implantation of skeletal beads and muscular electrodes.

Methods

During preanaesthetic examination, the following variables were assessed: heart (HR) and respiratory (fR) rates, and response to palpebral, corneal and toe- and tail-pinch withdrawal reflexes. The crocodiles were injected IM with an initial combination of medetomidine and ketamine and re-evaluated at 5 minute intervals for 20 minutes, or until they appeared unresponsive. If that did not occur, the drugs were redosed according to a decision tree based on the observed effects. The righting, biting and palatal valve reflexes were assessed in the unresponsive crocodiles, and used to confirm anaesthetic induction. Anaesthesia was maintained with sevoflurane in oxygen. At the end of surgery, medetomidine was antagonized with IM atipamezole.

Results

The decision tree identified 0.3 mg kg?1 medetomidine and 15 mg kg?1 ketamine as a useful drug combination, which resulted in anaesthetic induction and surgical anaesthesia 16 ± 8 and 16 (25–20) minutes after injection, respectively. Compared to baseline, HR and fR significantly decreased after anaesthetic induction (p < 0.001), but then remained stable throughout surgery. Intraoperatively, cloacal temperature [27 (26–30) °C] did not change over time (p = 0.48). The total dose of atipamezole was 2 (1–3) mg kg?1 and time to recovery was 36 (20–60) minutes. Perioperative complications were not observed.

Conclusions

and clinical relevance Medetomidine and ketamine, injected IM and followed by sevoflurane anaesthesia, may be regarded as a useful anaesthetic technique for juvenile Nile crocodiles undergoing minimally invasive experimental surgery.  相似文献   
43.
The camel (Camelus dromedarius) is well adapted to the utilization of vegetation of low nutritional value in its natural habitat zone, thanks to its aptitude to vary food and to search plants that are rich in water content and that can make up for its nutritional deficits, particularly as concerns mineral elements. Therefore, a survey was carried out to determine camels pasture quality, dietary preference and to characterize the chemical characteristics and nutritional value of different halophytes plants in a region of Southern Tunisia during spring season. Laboratory analysis were conducted on fourteen vegetable species appertained to seven different botanical families: Chenopodiaceae, Graminaceae, Tamaricaceae, Zygophyllaceae, Asteraceae, Frankeniaceae and Plumbaginaceae. Data obtained indicate an high variability of nutritional content of halophytes plants preferred by camels, specially for dry matter, crude protein, fiber fractions, ash and mineral elements.  相似文献   
44.
A 6-year-old spayed female ferret (Mustela putorius furo) exhibiting clinical signs of weakness, anorexia, lethargy, weight loss, and frequent urination was presented for a veterinary evaluation to determine the underlying cause of the aforementioned abnormal behavior and clinical condition. Physical examination revealed a large, firm, painless, movable subcutaneous mass at the base of the tail. Radiographic and ultrasound images confirmed the presence of a soft tissue mass compressing the sacrococcygeal vertebrae, but there was no evidence of metastatic lesions. Because of the poor prognosis and progressive deterioration of the animal's clinical condition, the ferret was humanely euthanized. Gross necropsy revealed a 4 × 4 × 3.5 cm, firm, yellow-tan, ovoid, subcutaneous mass wrapped around the rectum and the anus. The mass did not appear to breach the serosa. Evaluation of the abdominal cavity revealed a pale yellow liver, possibly associated with hepatic lipidosis with no gross evidence of metastasis in the body cavity. The histopathological features of the mass were consistent with a liposarcoma. To the best of the authors' knowledge, this is the first case of subcutaneous liposarcoma reported in a ferret.  相似文献   
45.
Lung dendritic cells (DCs) are potent antigen presenting cells (APCs) that initiate and modulate the adaptive immune response upon microbial infection within the pulmonary environment. For the first time, neonatal and adult lung DCs in a large animal model were compared in these studies. Here, we isolated and identified lung DCs in both neonatal and adult sheep, a valuable experimental animal utilized in pulmonary studies of naturally occurring respiratory diseases. Neonatal lung DCs exhibited characteristic dendrites and morphology when observed by transmission electron microscopy and expressed low to moderate DEC-205, CD80/86, MHC class II and CD 14. Regardless of age, lung DCs were functionally able to endocytose FITC conjugated ovalbumin but to a lesser degree than monocyte-derived DCs. In addition, neonatal lung DCs were demonstrated to be potent stimulators of allogeneic T cell proliferation. Together, these results demonstrate that neonatal and adult lung DCs are functionally similar. It is apparent from the data presented that neonatal pulmonary DCs do not exhibit an intrinsic functional defect that would impair their ability to take up antigen and stimulate na?ve T cells. These data support growing evidence that neonatal immune responses may differ from adults due to different microenvironmental influences rather than differences in dendritic cell maturation states.  相似文献   
46.
47.

Purpose

An analytical database containing XRF chemical analyses and real density measurements of unconsolidated sediments of the Padania Plain (Northern Italy) has been used to understand the relationship that exists between the soil particle density (ρs) and their bulk chemical composition.

Materials and methods

Using a linear regression, we built an equation able to link the particle density with the soil elemental composition.

Results and discussion

Positive correlations were found between ρs and SiO2, MgO, CaO and Na2O and negative correlations with K2O, TiO2, Al2O3, Fe2O3 and LOI, reflecting the presence in the soils of quartz and feldspars/mineral clays respectively.

Conclusions

Our equation is very useful because it helps to know the density properties of a soil when it is not possible to measure ρs with a pycnometer. On the other hand, by knowing the ρs, it is possible to have a quite precise knowledge about the chemistry of the studied soils.
  相似文献   
48.
The potential of fruit storage facilities that are contaminated with the widely used chemical antioxidant diphenylamine to cross-contaminate untreated apples (Malus × domestica Borkh.) was studied. A new sample preparation method identified the storage room paint, contaminated from past treatments, as the major source of cross-contamination in the analyzed facilities. Diphenylamine amounts of up to 917 g were found in a single storage room and were shown to correlate with the extent of cross-contamination on stored apples. Our data support a diffusion-based mechanism where the wall paint releases the antioxidant to the storage room atmosphere even years after the last treatment. Given the extent of cross-contamination found in our model experiments and under commercial storage conditions, we deduce a significant risk of exceeding the potentially upcoming maximum residue level of 0.01 mg kg(-1) on stored fruit in contaminated rooms even years after the last diphenylamine treatment.  相似文献   
49.
The soil quality index (SQI) for cacao cropping systems was developed to meet the nutritional criteria of the crop, the environmental safety of the cropping sites and the increasing demand for the production and quality of cocoa. Available water function (AWF), root growth function (RGF), mineral nutrition of plants function (MNF) and environmental safety function (ESF) for potentially toxic elements were included in the additive model of SQI for cacao cropping systems. In this study, over 66% of the cacao fields cropping sites were classified as regular SQI with a range of scores between 0.42 and 0.61. The field cropping site with the highest score (0.73) characterized as typic Alitic Red-Yellow Argisol was rated with high SQI. In contrast, the field cropping sites characterized as abrupt Cohesive Dystrophic Red-Yellow Argisol (0.29), typic Dystrophic Haplic Cambisol (0.39), and latosolic Dystrophic Yellow Argisol (0.40) were rated with low SQI. MNF and AWF were the functions that most contributed to the increase or decrease of SQI scores. The SQI adapted expressed the agro-environmental reality of cacao cropping systems of Bahia, Brazil, and this could be a versatile tool to subsidize the adequate soil management of cacao plantations around the world.  相似文献   
50.
Nonhuman primates represent the most relevant model organisms to understand the biology of Homo sapiens. The recent divergence and associated overall sequence conservation between individual members of this taxon have nonetheless largely precluded the use of primates in comparative sequence studies. We used sequence comparisons of an extensive set of Old World and New World monkeys and hominoids to identify functional regions in the human genome. Analysis of these data enabled the discovery of primate-specific gene regulatory elements and the demarcation of the exons of multiple genes. Much of the information content of the comprehensive primate sequence comparisons could be captured with a small subset of phylogenetically close primates. These results demonstrate the utility of intraprimate sequence comparisons to discover common mammalian as well as primate-specific functional elements in the human genome, which are unattainable through the evaluation of more evolutionarily distant species.  相似文献   
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