Productivity under Shade and Different Nutrient Solution of Hydroponic Watercress (Nasturtium officinale R. BR.)

Commercialization of watercress in the Sierra Norte mountain range in Oaxaca, Mexico principally relies on harvesting plants growing on riverbanks; however, semi-intensive cultivation throughout the year could be established as an alternative for the region. With this as an objective, the present study was carried out using the laminar flow of nutrients technique to evaluate four solutions of different macronutrients and four shade percentages. Treatment distribution was formulated according to a bifactorial arrangement. Four harvest periods were employed, in April, June, September, and November of 2010. Yields and vegetative growth of watercress decreased linearly with increasing shade levels. The best results were obtained with a nutrient solution using an electrical conductivity (EC) of 0.90 dS m^?1. Shade cloth percentages higher than 10% caused a significant decrease in total cycle production; the use of shade cloth is not recommended during seasons with low incident radiation.     

The Effects of Copper and Lead on Growth and Zinc Accumulation of Thlaspi Caerulescens J. and C. Presl: Implications for Phytoremediation of Contaminated Soils

Thlaspi caerulescens J. and C. Presl is a Zn-hyperaccumulatingplant which has aroused considerable interest with respect to its possible use for phytoremediation of Zn-contaminated soils. In this work, a British population of T. caerulescens, from a soil which was found to have relatively high concentrations of water-extractable Cu (0.22 mg L^-1), Pb (0.99 mg L^-1) and Zn (6.49 mg L^-1), was studied. Its ability to grow and accumulate Zn from hydroponic nutrient solution in the presence of elevated concentrations of Cu and/or Pb was investigated. The chosen concentrations of Cu, Pb and Zn were based on reported water-soluble concentrations of these heavy metals in contaminated soils. When supplied with 32.7 mg L^-1 Zn, plants accumulated 19 780 mg kg^-1 Zn in their shoot dry matter. This concentration declined by 9.3, 87 and 84% respectively when 5.0 mg L^-1 Pb, 1.0 mg L^-1 Cu or 2.0 mg L^-1 Cu were included in the nutrient solution. Despite the apparent adaptation of this population of T. caerulescens to a Zn/Pb/Cu-contaminated soil, these Cu treatments strongly inhibited growth, but the Pb treatment did not affect growth significantly.     

Distance to flood meadows as a predictor of use of <Emphasis Type="Italic">Nothofagus pumilio</Emphasis> forest by livestock and resulting impact,in Patagonia,Argentina

Seedling browsing by livestock has been indicated as major threat for forest sustainability use. Nothofagus pumilio forests are part of the livestock raising system in Patagonia, but because of the sparse understory cover, livestock graze mainly on flood meadows within the forest matrix. The complexity of the environment under study (forests and flood meadows) means that an adaptive predictor is needed to evaluate the intensity of resource use by livestock in order to assess its effect on the forest. Distance to flood meadows was evaluated as a predictor of the use intensity of the forest by livestock and its effect on the understory. The study was conducted at three sites in Chubut Province, Patagonia–Argentina. We established transects in the forest 320 m long, starting at the edge flood meadow-forest. In these transects, the livestock presence indicators (soil compaction, density of feces and trails) and composition of the understory were evaluated. Generalized Linear Model for repeated measures for longitudinal data were used. The indicators showed that distance is efficient for estimating forest use intensity by livestock. The understory varied with distance, the cover of exotic herbaceous was higher near the flood meadow. Far from the flood meadow, the cover was entirely composited of native species. The results support the use of distance to flood meadows as a tool for decision making in livestock and forest management in N. pumilio forests, and for further research on livestock effect on the forest.     

Seroincidence of porcine T. solium infection in the Peruvian highlands

We performed repeated serological sampling of pigs in an endemic area of the Peruvian highlands (eight villages) to assess the feasibility of detecting incident cases of Taenia solium infection as indicators of ongoing transmission of the parasite. A total of 2245 samples corresponding to 1548 pigs were collected in three sampling rounds (n=716, 926, and 603, respectively). Village-period specific seroprevalences of antibodies by enzyme-linked immunoelectrotransfer blot (EITB) assay varied from 39% (95% CI: 34, 44) to 76% (95% CI: 72, 79). The prevalence of cysticercosis increased with the age of the pigs (similarly for both sexes). Around 40% of pigs were re-sampled at the end of each 4-month period. Crude incidence risks were 48% (57/120, 95% CI: 43–52) and 58% (111/192, 95% CI: 54–61) for each period. A proportion of seropositive animals became seronegative at the end of each period (23 and 15%). Incidence varied by the village, and the exposure period, and was higher in males than females (but did not differ by age).     

Standardized ileal digestibility of proteins and amino acids in sesame expeller and soya bean meal in weaning piglets

Apparent ileal digestibility (AID) of diets containing sesame expeller (SE) and soya bean meal (SBM) was determined using 15 piglets (Genetiporc^®), weaned at 17 ± 0.4 days with average body weight of 6.4 ± 0.7 kg (Fertilis 20 × G Performance, Genetiporc^®, PIC México, Querétaro, México). Piglets were randomly assigned to three treatments: (i) a reference diet with casein as the sole protein source; (ii) a mixed diet of casein–SE; and (iii) a mixed diet of casein–SBM. The chemical composition of SE and SBM was determined, and AID and standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AAs) were determined for each protein source. SE contained greater quantities of ether extract, neutral detergent fibre, phytic acid, methionine and arginine than SBM. Lysine and proline contents and trypsin inhibitor activity were higher in SBM than in SE. The AID and SID of CP and AA (except for lysine and proline) were similar in SE and SBM. The AID of lysine and proline was higher in SBM than in SE (p < 0.05), and the SID of proline was higher in SE than in SBM (p < 0.05). These findings indicate that SE is an appropriate alternative protein source for early weaned pigs.     

Effects of induced hypothyroidism on ovarian response to superovulation in Brahman (Bos indicus) cows.

To evaluate the effects of hypothyroidism on ovarian function, multiparous, nonlactating Brahman cows (n = 18) were assigned randomly to dietary treatments containing either 0 (C; n = 9) or 4 mg x kg BW(-1) x d(-1) 6-n-propyl-2-thiouracil (PTU; n = 9), to suppress thyroid function, in the feed concentrate. Weekly changes in BW and body condition score (BCS) were recorded. Dietary treatments began on d 10 of the estrous cycle. Ten days after the first treatment estrus, all cows received daily i.m. injections of 25 IU of porcine FSH over a 3-d period. Seven days after AI, embryos were collected nonsurgically, and the ovaries were removed via midflank laparotomy. Based on thyroxine (T4) concentrations after 49 d of treatment, five cows were hypothyroid (H-PTU) and four were partially suppressed (P-PTU). Cows in the PTU group had greater (P<.01) ADG, (P<.05) ovarian weights, and numbers of large (> or =8 mm) (P<.05) follicles. Cows in the PTU group had lower embryo recovery rate (P<.001), fertilization rate (P<.001), and percentage of blastocysts (P<.1) than C cows. The H-PTU cows had greater numbers of luteinized follicles (P<.06), greater concentrations of progesterone (P4) in the follicular fluid at all size categories (P<.1), and greater numbers of corpora lutea (P<.05) than C cows. The ratio of luteal to serum P4 on d 7 was greater (P<.05) in hypothyroid cows. Induced hypothyroidism improved weight gain and BCS, increased ovarian response to FSH, and affected ovulation, fertility, and P4 secretion in superovulated Brahman cows.     

Seismicity remotely triggered by the magnitude 7.3 landers, california, earthquake

The magnitude 7.3 Landers earthquake of 28 June 1992 triggered a remarkably sudden and widespread increase in earthquake activity across much of the western United States. The triggered earthquakes, which occurred at distances up to 1250 kilometers (17 source dimensions) from the Landers mainshock, were confined to areas of persistent seismicity and strike-slip to normal faulting. Many of the triggered areas also are sites of geothermal and recent volcanic activity. Static stress changes calculated for elastic models of the earthquake appear to be too small to have caused the triggering. The most promising explanations involve nonlinear interactions between large dynamic strains accompanying seismic waves from the mainshock and crustal fluids (perhaps including crustal magma).     

Selective and Apoptotic Action of Ethanol Extract of Annona cherimola Seeds against Human Stomach Gastric Adenocarcinoma Cell Line AGS

Plant Foods for Human Nutrition - Annona cherimola is a tree belonging to the family Annonacea, whose fruit (cherimoya) is very desirable, but its seeds are considered waste. Present in these seeds...     

Interaction of Thalassia testudinum Metabolites with Cytochrome P450 Enzymes and Its Effects on Benzo(a)pyrene-Induced Mutagenicity

The aim of the present work was to evaluate the effects of Thalassia testudinum hydroethanolic extract, its polyphenolic fraction and thalassiolin B on the activity of phase I metabolizing enzymes as well as their antimutagenic effects. Spectrofluorometric techniques were used to evaluate the effect of tested products on rat and human CYP1A and CYP2B activity. The antimutagenic effect of tested products was evaluated in benzo[a]pyrene (BP)-induced mutagenicity assay by an Ames test. Finally, the antimutagenic effect of Thalassia testudinum (100 mg/kg) was assessed in BP-induced mutagenesis in mice. The tested products significantly (p < 0.05) inhibit rat CYP1A1 activity, acting as mixed-type inhibitors of rat CYP1A1 (Ki = 54.16 ± 9.09 μg/mL, 5.96 ± 1.55 μg/mL and 3.05 ± 0.89 μg/mL, respectively). Inhibition of human CYP1A1 was also observed (Ki = 197.1 ± 63.40 μg/mL and 203.10 ± 17.29 μg/mL for the polyphenolic fraction and for thalassiolin B, respectively). In addition, the evaluated products significantly inhibit (p < 0.05) BP-induced mutagenicity in vitro. Furthermore, oral doses of Thalassia testudinum (100 mg/kg) significantly reduced (p < 0.05) the BP-induced micronuclei and oxidative damage, together with an increase of reduced glutathione, in mice. In summary, Thalassia testudinum metabolites exhibit antigenotoxic activity mediated, at least, by the inhibition of CYP1A1-mediated BP biotransformation, arresting the oxidative and mutagenic damage. Thus, the metabolites of T. testudinum may represent a potential source of chemopreventive compounds for the adjuvant therapy of cancer.