Removal of Copper and Cadmium Ions from Diluted Aqueous Solutions by Low Cost and Waste Material Adsorbents

The sorption of copper and cadmium ions using activated carbon,kaolin, bentonite, diatomite and waste materials such as compost,cellulose pulp waste and anaerobic sludge as sorbents is reported. Equilibrium isotherms were obtained for the adsorption of these metals in single and binary solutions. Bentonite presented the highest adsorption capacities for both copper and cadmium. A competitive uptake was observed when both metals are present; copper being preferentially adsorbed by all materials with theexception of anaerobic sludge. Equilibrium data were fitted toLangmuir and Freundlich models, with satisfactory results for most of the adsorbent-metal systems studied.Of all the adsorbents studied, bentonite and compost presentedthe highest removal efficiencies, reaching 99% for copper whencadmium is also present, for initial solution concentrations ofup to 100 mg L^-1. Anaerobic sludge has a greater preferencefor cadmium, even in the presence of copper, with removal efficiencies of 98% for similar concentrations to those mentioned above.     

Experimental study of antibiotic-induced immunosuppression in mice—I. Humoral and cell-mediated immune responsiveness related to in vivo antibiotic treatment

By using CBA/J mice as responders, the immunodepressive effect of seven antibacterial chemotherapeutic agents was tested, i.e. penicillin (pen), streptomycin (str), erythromycin (erm), kanamycin (kan), tetracycline (tet), colistin (col) and chloramphenicol (chl). Lymphocytotoxicity power, as well as the ability of each drug to influence secondary humoral (against sheep red blood cells or diphtheria anatoxin) or cell-mediated (against PPD and Coxsackie A₉ virus) immunity were searched.

Erm, col and chl markedly depressed humoral and cell-mediated immune responsiveness in vitro after in vivo treatment with non-cytotoxical amounts. The Th lymphocyte supplementation of B reactive spleen cell population recovered the immune capacity in col and chl in vivo-treated groups, but not in erm-treated group.     

Impact of silicon-based quantum dots on the antioxidative system in white muscle of Carassius auratus gibelio

Silicon-based quantum dots were intraperitoneally injected in individuals of Carassius auratus gibelio. Their effects on white muscle were investigated by following their distribution and impact on the antioxidative system. The GSH level significantly increased after 1 and 3?days of exposure by, respectively, 85.3 and 25.4%. Seven days later, GSH levels were similar to control concentrations. MDA concentration rose after three days by 46.9% and remained at the same level after 7?days. Protein thiol levels significantly decreased by 6.7 and 8.1% after 3 and 7?days, whereas advanced oxidation protein products increased by 12.7, respectively, 28.1% in the same time intervals. The protein reactive carbonyl groups were raised only after the first day of exposure and returned to the control level later on. SOD specific activity increased up to 48% after 7?days, while CAT activity increased by 328, 176, and 26% after 1, 3, and 7?days of treatment. GST specific activity was up-regulated by 87, 18, and 9%, while GR activity increased by 68, 34, and 9%. G6PD activity was up-regulated by 12, 22, and 50%, whereas GPx activity raised by 75 and 109% compared to control after, respectively, 1, 3, and 7?days. Our results suggest that oxidative stress induced by silicon-based quantum dots was not strong enough to cause permanent damage in the white muscle of crucian carp.     

Light response of hydraulic conductance in bur oak (Quercus macrocarpa) leaves

A four- to seven-fold enhancement of leaf hydraulic conductance by light has been reported in three temperate tree species. The enhancement occurs in the liquid-flow pathway between the petiole and the site of water evaporation. The enhancement occurs within 1 h, and dissipates in darkness over a period of 1 to 10 h depending on species. Here we report light-induced enhancement of leaf hydraulic conductance in a fourth species, bur oak (Quercus macrocarpa Michx.), the dependence of the effect on light flux and color, its absence in leaves of seedlings, and the impact on the response of leaf vein severance and several metabolic inhibitors. The light response of leaf hydraulic conductance approached saturation at a photosynthetic photon flux of 150 mumol m(-2) s(-1). Hydraulic enhancement was greater in response to blue and green light than to visible radiation of longer wavelengths, although at the same irradiance, the response to white light was greater than to light of any single color. Atrazine (a photosystem II inhibitor), fusicoccin (which stimulates plasma membrane-bound H(+)-ATPase) and HgCl(2) (an aquaporin blocker) reduced the light response of leaf lamina hydraulic conductance. When 2-mercaptoethanol was added following mercury treatment, the light response was totally suppressed. Our results are consistent with the notion that the effect of light on leaf lamina hydraulic conductance is controlled by factors acting outside the leaf veins, possibly through light-induced changes in membrane permeability of either mesophyll or bundle sheath cells, or both.     

Micropylar pollen tube guidance by egg apparatus 1 of maize

Pollen tube guidance precedes the double fertilization of flowering plants. Here, we report the identification of a small maize protein of 94 amino acids involved in short-range signaling required for pollen tube attraction by the female gametophyte. ZmEA1 is exclusively expressed in the egg apparatus, consisting of the egg cell and two synergids. Chimeric ZmEA1 fused to green fluorescent protein (ZmEA1:GFP) was first visible within the filiform apparatus and later was localized to nucellar cell walls below the micropylar opening of the ovule. Transgenic down-regulation of the ZmEA1 gene led to ovule sterility caused by loss of close-range pollen tube guidance to the micropyle.     

Investigation of Organic Solvent Resistance Mechanisms in Vibrio alginolyticus IBBCt2

Constanta harbor has been contaminated for decades with petroleum and petroleum products, which contain different toxic organic solvents. A novel solvent-tolerant bacterium, Vibrio alginolyticus IBB_Ct2 was isolated from a seawater sample (Constanta harbor). Alkanes (i.e., n-hexane, n-decane, cyclohexane) with logarithm of partition coefficient in n-octanol and water (log P _OW )?>?3.35, were less toxic for V. alginolyticus strain IBB_Ct2, compared with aromatics (i.e., toluene, m-xylene, ethylbenzene) with log P _OW? <?3.17. The high organic solvent resistance of V. alginolyticus IBB_Ct2 could be due to the presence of some catabolic (alkB, alkB/alkB1, todC1, xylM, C23DO) and transporter (HAE1, acrAB) genes. The adaptation mechanisms, underlying cyclohexane, n-hexane, n-decane, toluene, m-xylene, and ethylbenzene resistance in V. alginolyticus IBB_Ct2 showed a complex response of cells 60?min after solvent shock (i.e., modifications of the cell viability, changes in the membrane??s lipid and protein profile, modifications of the genomic fingerprinting). Exposure of V. alginolyticus IBB_Ct2 cells to salt stress decreases the organic solvents tolerance of this bacterium.     

Assessment of a bone glue-based foliar fertilizer on tomato quality production

Tomatoes are consumed and cultivated all over the world for not only their pleasant taste but also their curative properties. Therefore, the challenge for growers is to obtain high-quality crop productions by developing new varieties of tomatoes or new ecofriendly fertilizers. This study was to test a bone glue-based foliar fertilizer on the tomato crop. The experiment was organized in a vegetation house under an original treatment scheme. Four types of foliar fertilizers were tested: macroelements, microelements and glue; macroelements and glue; microeleements and glue; and macroelements and microelements without glue. The fertilizers were applied as diluted solutions (0.5% and 1%) across three treatments applied on nine variants. The treatments with bone glue-based foliar fertilizer led to a high-quality production of healthy tomatoes, a good absorption of nutrients together with a reduced nitrites level in tomatoes and an increase of agricultural productivity. The applied foliar fertilizers tested on the hybrid tomatoes used in the experiment had a significant positive influence on vegetative growth. The nitrate concentration in the fruit did not exceed the maximum accepted level. The agronomic analysis of the mineral composition of the fruit revealed that foliar fertilizers with glue significantly influenced nutrient assimilation during the treatments. The level of nitrogen (N), phosphorus (P), and potassium (K) recovery following the application of bone glue foliar fertilizers was higher as compared to the control and the variant without bone glue. Biometric measurements had shown significant differences favorable to tomatoes treated with this bone glue foliar fertilizer.