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41.
The Carbon Concentration Mechanism (CCM) allows phytoplakton species to accumulate the dissolved inorganic carbon (DIC) necessary for an efficient photosynthesis even under carbon dioxide limitation. In this mechanism of primary importance for diatoms, a key role is played by carbonic anhydrase (CA) enzymes which catalyze the reversible hydration of CO2, thus taking part in the acquisition of inorganic carbon for photosynthesis. A novel CA, named CDCA1, has been recently discovered in the marine diatom Thalassiosira weissflogii. CDCA1 is a cambialistic enzyme since it naturally uses Cd2+ as catalytic metal ion, but if necessary can spontaneously exchange Cd2+ to Zn2+. Here, the biochemical and structural features of CDCA1 enzyme will be presented together with its putative biotechnological applications for the detection of metal ions in seawaters.  相似文献   
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The parasitoid complex of the Asian chestnut gall wasp Drycosmus kuriphilus Yasumatsu was studied in Calabria (Italy). A total of 14 different species of parasitoids were collected, of which three are recorded on the Asian gall wasp for the first time. The composition of the parasitoid complex collected in Calabria was compared with that reported from Italy and from Europe. The altitude of the sites of collection seemed to have an effect on the distribution and abundance of the single species of parasitoids.  相似文献   
44.
Healing of wounds located on the distal limbs of horses is often complicated by retarded epithelialization and the development of exuberant granulation tissue (proud flesh). Treatments that definitively resolve this pathological process are still unavailable. Molecular studies of the repair mechanism might contribute to the development of new therapeutic strategies. The study presented herein aimed to clone the full length cDNA and to study the spatio-temporal expression profile of mRNA and protein for LAMR1, previously attributed a role in wound epithelialization, during the repair of body and limb wounds in the horse. Cloning was achieved by screening a cDNA library previously derived from 7-day wound biopsies. Expression was studied in unwounded skin and in samples from 1-, 2-, 3-, 4- and 6-week-old wounds of the body and limb. Temporal gene expression was determined by real time polymerase chain reaction (RT-PCR) while protein expression was mapped immunohistochemically. Full-length cDNA for equine LAMR1 was shown to be highly similar to that of other species. The mRNA expression of LAMR1 was significantly up-regulated only in thoracic wounds, 4 and 6 weeks following wounding (upon epithelialization). Cutaneous wounding induced protein expression at both locations. Our data suggest that up-regulation of LAMR1 protein might favour epithelialization during wound healing. However, its interaction with ligands other than laminin complicates data interpretation. Future studies should quantitatively verify the temporal expression of this protein in order to provide the basis for targeted therapies that might enhance epithelialization.  相似文献   
45.
Forty-three secondary metabolites were isolated and characterized from cv. Annurca apple fruit, an apple variety cultivated in the south of Italy. This apple cultivar undergoes a typical reddening treatment after collection. All of the compounds were characterized on the basis of their spectroscopic data. The compounds were tested for their radical-scavenging and antioxidant activities by measuring their capacity to scavenge DPPH* (2,2'-diphenyl-1-picrylhydrazyl radical), H2O2, and NO (nitric oxide) and to inhibit the formation of methyl linoleate conjugated diene hydroperoxides or TBARS (thiobarbituric acid reactive species).  相似文献   
46.
Leucettamols, bifunctionalized sphingoid-like compounds obtained from a marine sponge Leucetta sp., act as non-electrophilic activators of the TRPA1 channel and potent inhibitors of the icilin-mediated activation of the TRPM8 channel, while they are inactive on CB1, CB2 and TRPV1 receptors. Leucettamols represent the first compounds of marine origin to target TRPA1 and the first class of natural products to inhibit TRPM8 channels. The preparation of a small series of semi-synthetic derivatives revealed interesting details on the structure-activity relationships within this new chemotype of simple acyclic TRP modulators.  相似文献   
47.
The summer flounder, Paralichthys dentatus L., is a high‐value species and considerable research has been conducted to determine practices conducive for its culture. As milt can be limited in this species, experiments were conducted to develop a practical sperm cryopreservation protocol for hatchery use. Two dilution ratios (1:2 and 1:4; sperm:extender), 2 diluents (saline and sucrose‐based), 2 cryoprotectants (10% DMSO and 12% glycerol) and 3 freezing rates (?5, ?10 and ?15°C min?1) were evaluated using differential staining to assess post‐thaw sperm survival. Seven combinations of the factors examined reduced post‐thaw viability by less than 30%. The average viability of sperm from fresh, pooled flounder milt (67.2 ± 2.9%) was not different from that of thawed milt diluted 1:4 with sucrose diluent (10% DMSO) frozen at ?5°C min?1 (38.4 ± 7.7%) and fertilization and hatch success were not different in trials using fresh or thawed, cryopreserved sperm. From these experiments a practical sperm cryopreservation method was developed, but further refinement of the freezing protocol is necessary to optimize results.  相似文献   
48.
Animal growth does not follow a linear pattern, being explained mathematically by functions that have parameters with biological meaning. These parameters are used to estimate the expected weight of animals at specific ages. Several nonlinear models have been used to describe growth. This study was carried out to estimate the parameters of logistic, Gompertz, Richards and von Bertalanffy growth curve models in a sample of Podolica young bulls to determine the goodness of fit. Animals were weighed every 3 months from birth to 810 days of age. The results indicate that all the growth models used were easily fitted to the observed data with Gompertz and logistic functions presenting less computational difficulty in terms of number of iterations to achieve convergence. Moreover, logistic and Richards equations provided the best overall fit being useful to describe the growth of Podolica bulls. Considering that the literature lacks information on growth curves in Podolica breed, the study of a mathematical model for growth describing the developmental pattern of a specific population within a peculiar environment is a useful tool to improve Podolica breed production.  相似文献   
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Volatile organic compounds (VOCs) cause global and local impacts, resulting in environmental, health, and economic adverse effects. Industrial and waste management activities are the main anthropogenic stationary sources of VOCs in the atmosphere. The traditional technologies for the treatment of VOC-contaminated air present several limitations when treating effluents with low VOC concentrations, high airflow rate, and with compounds with low solubility in water. However, a novel technology, based on non-thermal plasmas (NTPs) and catalysis, has shown promising results in air purification. In this framework, after an initial overview on NTP-catalysis principles, this review presents and discusses 20 recent papers, with a threefold purpose: evaluating the most recent applications of NTP and NTP-catalysis reactors to the treatment of air-VOC mixtures, analyzing all the parameters that may influence the abatement efficiency and the by-product formation, and providing the reader with insights into the choice of the preferable configurations to use, based on the effluent type and the destination of the treated air. As a result of this review, NTPs may represent a promising option for indoor air treatment, especially because of the lower expected byproduct formation when treating low-concentrated VOC mixtures with relatively low air flow rates. If the target is the abatement of higher VOC concentrations, the higher energy efficiency obtainable in such conditions makes NTP-catalysis a cost-effective option for industrial applications. In addition, the formation of simpler and more soluble by-products makes NTPs a suitable technology for air pretreatment upstream of water-based removal technologies, such as absorption columns and biofilters.  相似文献   
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