Fragmentation patterns and implications for biodiversity conservation in three biosphere reserves and surrounding regional environments, northeastern Mexico

Patterns of fragmentation in current distributions of 35 species of birds and 19 species of mammals that are considered endangered, threatened, or with restricted distributions were modeled in relation to 3 biosphere reserves (El Abra-Tanchipa, El Cielo, Sierra Gorda; ‘BRs’) and 13 areas identified as priorities for conservation in northeastern Mexico (PAC-Priority Areas for Conservation). Core area percentage of landscape (CPLAND) and aggregation index (AI) were used to summarize fragmentation trends in species’ geographic distributions, modeled using ecological niche modeling techniques. Overall (median) CPLAND and AI revealed: (a) for birds, El Abra-Tanchipa BR and neighboring areas exhibited the lowest fragmentation (high CPLAND and high AI), whereas Sierra Gorda BR was the most fragmented; (b) for mammals, El Abra-Tanchipa and El Cielo BRs exhibited lowest overall fragmentation, while Sierra Gorda BR was the most fragmented. Although there were areas (i.e., El Abra-Tanchipa BR and Parras de la Fuente PAC) with higher combination of CPLAND and AI values, El Cielo BR stands out because of its high CPLAND and AI values along with the highest species richness.     

Hg, Cu, Pb, Cd, and Zn Accumulation in Macrophytes Growing in Tropical Wetlands

The concentrations of Hg, Cu, Pb, Cd, and Zn accumulated by regional macrophytes were investigated in three tropical wetlands in Colombia. The studied wetlands presented different degrees of metal contamination. Cu and Zn presented the highest concentrations in sediment. Metal accumulation by plants differed among species, sites, and tissues. Metals accumulated in macrophytes were mostly accumulated in root tissues, suggesting an exclusion strategy for metal tolerance. An exception was Hg, which was accumulated mainly in leaves. The ranges of mean metal concentrations were 0.035?C0.953 mg g^?1 Hg, 6.5?C250.3 mg g^?1 Cu, 0.059?C0.245 mg g^?1 Pb, 0.004?C0.066 mg g^?1 Cd, and 31.8?363.1 mg g^?1 Zn in roots and 0.033?C0.888 mg g^?1 Hg, 2.2?C70.7 mg g^?1 Cu, 0.005?C0.086 mg g^?1 Pb, 0.001?C0.03 mg g^?1 Cd, and 12.6?C140.4 mg g^?1 Zn in leaves. The scarce correlations registered between metal concentration in sediment and plant tissues indicate that metal concentrations in plants depend on several factors rather than on sediment concentration only. However, when Cu and Zn sediment concentrations increased, these metal concentrations in tissues also increased in Eichhornia crassipes, Ludwigia helminthorriza, and Polygonum punctatum. These species could be proposed as Cu and Zn phytoremediators. Even though macrophytes are important metal accumulators in wetlands, sediment is the main metal compartment due to the fact that its total mass is greater than the corresponding plant biomass in a given area.     

Recent changes in landscape structure and function in a mediterranean region of SW Spain (1950–1984)

Recent economic development has altered landscape structure and function of a mediterranean region in Southwestern Spain. Intensive agricultural systems have concentrated in the more fertile areas, while marginal ones have been abandoned. As a result, landscape structure has changed. Consequences of this structural change on landscape processes are discussed.     

Estrogen receptors alpha and beta and progesterone receptors in normal bovine ovarian follicles and cystic ovarian disease

The purpose of this study was to determine by immunohistochemistry the expression of estrogen and progesterone receptors in ovarian follicular structures from cows with cystic ovarian disease (COD) and to compare these with normal ovarian structures. Secondary, tertiary, atretic, and cystic follicles were evaluated. The follicular cysts of animals with COD presented a significantly higher expression of estrogen receptor alpha in all follicular layers than secondary, tertiary, and atretic follicles in both groups (P < .05). The intensity of estrogen receptor beta in the granulosa cell layer was stronger in tertiary than in secondary and atretic follicles in normal animals (P < .05) and in growing and cystic follicles in animals with COD (P < .05). Theca cells were scarcely stained in the 2 groups. Growing follicles and cysts from COD animals were less stained than tertiary follicles from normal animals (P < .05). Differences did not exist between the 2 groups with regard to the progesterone receptor. Ovaries of animals with COD exhibited altered estrogen receptors expression compared with that in normal animals.     

Intraovarian localization of growth factors in induced cystic ovaries in rats

We hypothesized that the special hormonal environment present in animals with cystic ovarian disease (COD) interferes with cellular production of growth factors (GFs). The objective of the present study was to characterize the expression of insulin-like growth factor (IGF)-I, fibroblast growth factor (FGF)-2 and vascular endothelial growth factor (VEGF) in induced COD using immunohistochemistry. We used an experimental model based on the exposure to constant light of adult rats during 15 weeks. We quantified the expression of GFs in cystic and normal ovaries by the Immunohistochemical Stained Area (IHCSA). In animals with COD, a significant reduction in the IHCSA of IGF-I in the follicular fluid, theca and granulosa layers of cysts occurred; and an increase in the interstitial tissue with regard to the control group. We found moderate immunoreactivity of FGF-2 in granulosa and theca layers of secondary and tertiary follicles and lower expression in the granulosa and theca interna layers of cystic follicles. Immunoexpression of VEGF was found in granulosa and theca cells of secondary and tertiary follicles. This study shows changes in the ovarian expression of IGF-I, FGF-2 and VEGF in induced COD. We can propose that an alteration in the control of the follicular dynamic, through the GFs, added to other features, could be involved in the ovarian cyst pathogenesis.     

Involvement of PAPP‐A and IGFR1 in Cystic Ovarian Disease in Cattle

Cystic ovarian disease (COD) is one of the main causes of infertility in dairy cattle. It has been shown that intra‐ovarian factors, such as members of the insulin‐like growth factor (IGF) system, may contribute to follicular persistence. The bioavailability of IGF to initiate its response by binding to specific receptors (IGFRs) depends on interactions with related compounds, such as pregnancy‐associated plasma protein A (PAPP‐A). The aim of this study was to determine IGFR1 and PAPP‐A expression both in follicles at different stages of development and in cysts, to evaluate the roles in the etiopathogenesis of COD in cattle. The mRNA expression of PAPP‐A was higher in granulosa cells of large tertiary follicles than in cysts, whereas the protein PAPP‐A present in the follicular fluid from these follicles showed no differences. Although no PAPP‐A mRNA expression was detected in smaller tertiary follicles, in their follicular fluid, this protease was detected in lesser concentration than in cysts. The mRNA expression of IGFR1 was lower in granulosa cells from cystic follicles than in those from tertiary ones. However, the protein expression of this receptor presented the highest levels in cystic structures, probably to increase the possibility of IGF response. The data obtained would indicate that animals with COD have an altered regulation of the IGF system in the ovary, which could be involved in the pathogenesis of this disease in cattle.     

Characterization of the Wx gene in diploid Aegilops species and its potential use in wheat breeding

Wx gene encodes for the granule-bound starch synthase I or waxy protein, which is the sole enzyme responsible for amylose synthesis in wheat seeds. The Aegilops species, which are related to wheat, could be important sources of variation in this gene. In addition to its role in starch quality, this gene has been used in phylogenetic studies of wheat. The current study evaluated the variability of Wx gene in seven diploid species of Aegilops genus and compared their nucleotide sequences with the wheat homeologous genes. Nineteen new Wx alleles were found in the seven species evaluated. The alleles detected in two species of the Sitopsis section, Ae. searsii and Ae. speltoides, were related to the Wx-B1 gene of wheat. Two more of the Sitopsis species did not appear to be associated with this genome, whereas the remaining species were related to the Wx-D1 gene of wheat. The results showed an important variation of the Wx gene present in the Aegilops genus, and the 19 new Wx alleles detected could enlarge the genetic pool of wheat.     

The 2010 Mw 8.8 Maule megathrust earthquake of Central Chile, monitored by GPS

Large earthquakes produce crustal deformation that can be quantified by geodetic measurements, allowing for the determination of the slip distribution on the fault. We used data from Global Positioning System (GPS) networks in Central Chile to infer the static deformation and the kinematics of the 2010 moment magnitude (M(w)) 8.8 Maule megathrust earthquake. From elastic modeling, we found a total rupture length of ~500 kilometers where slip (up to 15 meters) concentrated on two main asperities situated on both sides of the epicenter. We found that rupture reached shallow depths, probably extending up to the trench. Resolvable afterslip occurred in regions of low coseismic slip. The low-frequency hypocenter is relocated 40 kilometers southwest of initial estimates. Rupture propagated bilaterally at about 3.1 kilometers per second, with possible but not fully resolved velocity variations.     

Comparative analysis of physiological characteristics and yield components in sugarcane cultivars

Sugarcane in an important crop due to the economic value of its products. Physiological characteristics and yield components of sugarcane were studied in three field-grown sugarcane cultivars B 63118, POJ 2878 and Ja 60-5. Three growth stages were identified: formative phase (until 140 DAP), grand growth (140–300 DAP) and maturity (after 300 DAP). Results indicated that cultivars showed contrasting yield mainly after 300 DAP. At ripening, the most productive cultivar (Ja 60-5) achieved higher leaf area, an optimum leaf area index for light interception, a high and stable net assimilation rate and an elevated leaf area and biomass duration. In addition, this cultivar showed the higher density and lower area of leaf sieve elements as compared with other, which could influence the high translocation rate (1.85 cm min⁻¹) at 8 MAP. The higher efficiency of this process in Ja 60-5 might also be supported by a higher (15–25%) apparent free space of stem parenchyma as compared with POJ 2878 and B 63118. Our results suggest that Ja 60-5 reduced carbon partitioned to foliar respiration which led to a higher partitioning of sucrose to stems evidenced by a higher Pol%.     

Influence of blending on the content of different compounds in the biological aging of sherry dry wines

Principal components analysis to examine the effect of blending (viz. the mixing and transfer of wine between cask rows in a "criaderas and solera" system) on metabolic activity in flor yeasts during biological aging of sherry dry wines was carried out. The variables used in the analysis were the wine compounds most deeply involved in the flor yeast metabolism, namely ethanol, acetaldehyde, glycerol, acetic acid, and l-proline. The greatest blending effect was found to be on the third and second "criadera", which are the stages where the yeasts show a high metabolic activity. The stages holding the oldest wine (viz. the first criadera and the solera) exhibited no differences before and after blending; therefore, the yeasts have a decreased biological activity in them and physical-chemical aging processes seemingly prevail over it.