Spring-neap tide-induced beach water table fluctuations in a sloping coastal aquifer

Predictions of water table fluctuations in coastal aquifers are needed for numerous coastal and water resources engineering problems. Most previous investigations have been based on the Boussinesq equation for the case of a vertical beach. In this note an analytical solution based on shallow water expansion for the spring- neap tide- induced water table fluctuations in a coastal aquifer is presented. Unlike most previous investigations, multitidal signals are considered with a sloping coastal aquifer. The new solution is verified by comparing with field observations from Ardeer, Scotland. On the basis of the analytical approximation the influences of higher- order components on water table elevation are examined first. Then, a parametric study has been performed to investigate the effects of the amplitude ratio (lambda), frequency ratio (omega), and phases (delta(1) and delta(2)) on the tide- induced water table fluctuations in a sloping sandy beach.

Ferrolysis induced soil transformation by natural drainage in Vertisols of sub-humid South India

In sub-humid South India, recent studies have shown that black soil areas (Vertisols and vertic Intergrades), located on flat valley bottoms, have been rejuvenated through the incision of streambeds, inducing changes in the pedoclimate and soil transformation. Joint pedological, geochemical and geophysical investigations were performed in order to better understand the ongoing processes and their contribution to the chemistry of local rivers. The seasonal rainfall causes cycles of oxidation and reduction in a perched watertable at the base of the black soil, while the reduced solutions are exported through a loamy sand network. This framework favours a ferrolysis process, which causes low base saturation and protonation of clay, leading to the weathering of 2:1 then 1:1 clay minerals. Maximum weathering conditions occur at the very end of the wet season, just before disappearance of the perched watertable. Therefore, the by-products of soil transformation are partially drained off and calcareous nodules, then further downslope, amorphous silica precipitate upon soil dehydration. The ferrolysed area is fringing the drainage system indicating that its development has been induced by the streambed incision. The distribution of (14)C ages of CaCO(3) nodules suggests that the ferrolysis process started during the late Holocene, only about 2 kyr B.P. at the studied site and about 5 kyr B.P. at the watershed outlet. The results of this study are applied to an assessment of the physical erosion rate (4.8x10(-3) m/kyr) since the recent reactivation of the erosion process. (C) 2010 Elsevier B.V. All rights reserved.

Soil morphological control on saline and freshwater lake hydrogeochemistry in the Pantanal of Nhecolandia, Brazil

Joint pedological, geochemical, hydrological and geophysical investigations were performed to study the coexistence or saline and freshwater lakes in close proximity and similar climatic conditions in the Nhecolandia region, Pantanal wetlands in Brazil. The saline lakes are concentrically surrounded by green sandy loam horizons, which cause differential hydrological regimes. Mg-calcite, K-silicates, and amorphous silica precipitate in the soil cover, whereas Mg-silicates and more soluble Na-carbonates are concentrated in the topsoil along the shore of the saline lake. In saline solutions, some minor elements (As, Se) reach values above the water quality recommendations, whereas others are controlled and incorporated in solid phases (Ba, Sr). Locally, the destruction of the sandy loam horizons generates very acidic soil solution (pH similar to 3.5) through a process not yet understood. The soil distributions indicate that some freshwater lakes are former saline lakes. They are invaded by freshwater after destruction of the sandy loam green horizons, then the freshwater becomes enriched in K(+), SO(4)(2-), Fe, Al, and a stream of minor and trace elements. The formation of these green sandy loam horizons in the saline environment and their destruction in the non-saline one emphasizes the dynamic nature of this environment (C) 2008 Elsevier B.V. All rights reserved.

Low coral cover in a high-CO2 world

Coral reefs generally exist within a relatively narrow band of temperatures, light, and seawater aragonite saturation states. The growth of coral reefs is minimal or nonexistent outside this envelope. Climate change, through its effect on ocean temperature, has already had an impact on the world's coral reefs, with almost 30% of corals having disappeared since the beginning of the 1980s. Abnormally warm temperatures cause corals to bleach ( lose their brown dinoflagellate symbionts) and, if elevated for long enough, to die. Increasing atmospheric CO2 is also potentially affecting coral reefs by lowering the aragonite saturation state of seawater, making carbonate ions less available for calcification. The synergistic interaction of elevated temperature and CO2 is likely to produce major changes to coral reefs over the next few decades and centuries. Known tolerances of corals to projected changes to sea temperatures indicate that corals are unlikely to remain abundant on reefs and could be rare by the middle of this century if the atmospheric CO2 concentration doubles or triples. The combination of changes to sea temperature and carbonate ion availability could trigger large- scale changes in the biodiversity and function of coral reefs. The ramifications of these changes for the hundred of millions of coral reef - dependent people and industries living in a high- CO2 world have yet to be properly defined. The weight of evidence suggests, however, that projected changes will cause major shifts in the prospects for industries and societies that depend on having healthy coral reefs along their coastlines.

Elevated expression of MeCP2 in cardiac and skeletal tissues is detrimental for normal development

MeCP2 plays a critical role in interpreting epigenetic signatures that command chromatin conformation and regulation of gene transcription. In spite of MeCP2`s ubiquitous expression, its functions have always been considered in the context of brain physiology. In this study, we demonstrate that alterations of the normal pattern of expression of MeCP2 in cardiac and skeletal tissues are detrimental for normal development. Overexpression of MeCP2 in the mouse heart leads to embryonic lethality with cardiac septum hypertrophy and dysregulated expression of MeCP2 in skeletal tissue produces severe malformations. We further show that MeCP2`s expression in the heart is developmentally regulated; further suggesting that it plays a key role in regulating transcriptional programs in non-neural tissues.

Pulmonary Hypertension in Latin America Pulmonary Vascular Disease: The Global Perspective

Latin America is here defined as all of the Americas south of the United States. In the setting of pulmonary hypertension, there are social inequalities and geophysical aspects in this region that account for a high prevalence of certain etiologies. This review aimed to analyze some of these factors. Data were collected from the existing literature. Information also was obtained from local tertiary-care centers to where patients with pulmonary hypertension generally are referred. Further, local experience and expertise was taken into consideration. Three etiologies of pulmonary hypertension were found to be the most prevalent: schistosomiasis (similar to 1 million affected people in Brazil), high altitude (particularly in the Andes), and congenital heart disease (late diagnosis of congenital left-to-right shunts leading to development of pulmonary vasculopathy). The diversity in terms of ancestries and races probably accounts for the differences in phenotype expression of pulmonary hypertension when a given region is considered (eg, schistosomiasis-, high-altitude-, or congenital heart disease-associated pulmonary hypertension). Governmental measures are needed to improve social and economic inequalities with an obvious impact on certain etiologies, such as schistosomiasis and congenital heart disease. Early diagnosis of pulmonary hypertension and access to medication remain important challenges all over Latin America. CHEST 2010; 137(6)(Suppl):78S-84S

Molecular analysis of CYP21A2 can optimize the follow-up of positive results in newborn screening for congenital adrenal hyperplasia

Neonatal screening for congenital adrenal hyperplasia (CAH) is useful in diagnosing salt wasting form (SW). However, there are difficulties in interpreting positive results in asymptomatic newborns. The main objective is to analyze genotyping as a confirmatory test in children with neonatal positive results. Patients comprised 23 CAH children and 19 asymptomatic infants with persistently elevated 17-hydroxyprogesterone (17OHP) levels. CYP21A2 gene was sequenced and genotypes were grouped according to the enzymatic activity of the less severe allele: A1 null, A2 < 2%, B 3-7%, C > 20%. Twenty-one children with neonatal symptoms and/or 17OHP levels > 80 ng/ml carried A genotypes, except two virilized girls (17OHP < 50 ng/ml) without CAH genotypes. Patients carrying SW genotypes (A1, A2) and low serum sodium levels presented with neonatal 17OHP > 200 ng/ml. Three asymptomatic boys carried simple virilizing genotypes (A2 and B): in two, the symptoms began at 18 months; another two asymptomatic boys had nonclassical genotypes (C). The remaining 14 patients did not present CAH genotypes, and their 17OHP levels were normalized by 14 months of age. Molecular analysis is useful as a confirmatory test of CAH, mainly in boys. It can predict clinical course, identify false-positives and help distinguish between clinical forms of CAH.

Driving mechanisms for groundwater flow and salt transport in a subterranean estuary

This paper presents field measurements and numerical simulations of groundwater dynamics in the intertidal zone of a sandy meso-tidal beach. The study, focusing on vertical hydraulic gradients and pore water salinities, reveals that tides and waves provide important forcing mechanisms for flow and salt transport in the nearshore aquifer. Such forcing, interacting with the beach morphology, enhances the exchange between the aquifer and ocean. The spatial and temporal variations of vertical hydraulic gradients demonstrate the complexity and dynamic nature of the processes and the extent of mixing between fresh groundwater and seawater in a subterranean estuary''. These results provide evidence of a potentially important reaction zone in the nearshore aquifer driven by oceanic oscillations. Land-derived contaminants may undergo important biogeochemical transformations in this zone prior to discharge.

Genetic Contribution for Non-Syndromic Cleft Lip With or Without Cleft Palate (NS CL/P) in Different Regions of Brazil and Implications for Association Studies

Non-syndromic cleft lip with or without cleft palate (NS CL/P) is a complex disease in which heritability estimates vary widely depending on the population studied. To evaluate the importance of genetic contribution to NS CL/P in the Brazilian population, we conducted a study with 1,042 families from five different locations (Santarem, Fortaleza, Barbalha, Maceio, and Rio de Janeiro). We also evaluated the role of consanguinity and ethnic background. The proportion of familial cases varied significantly across locations, with the highest values found in Santarem (44%) and the lowest in Maceio (23%). Heritability estimates showed a higher genetic contribution to NS CL/P in Barbalha (85%), followed by Santarem (71%), Rio de Janeiro (70%), Fortaleza (64%), and Maceio (45%). Ancestry was not correlated with the occurrence of NS CL/P or with the variability in heritability. Only in Rio de Janeiro was the coefficient of inbreeding significantly larger in NS CL/P families than in the local population. Recurrence risk for the total sample was approximately 1.5-1.6%, varying according to the location studied (0.6-0.7% in Maceio to 2.2-2.8% in Barbalha). Our findings show that the degree of genetic contribution to NS CL/P varies according to the geographic region studied, and this difference cannot be attributed to consanguinity or ancestry. These findings suggest that Barbalha is a promising region for genetic studies. The data presented here will be useful in interpreting results from molecular analyses and show that care must be taken when pooling samples from different populations for association studies. (C) 2011 Wiley-Liss, Inc.

Satellite observation and climate system model simulation of the St. Lawrence Island polynya

The St. Lawrence Island polynya (SLIP) is a commonly occurring winter phenomenon in the Bering Sea, in which dense saline water produced during new ice formation is thought to flow northward through the Bering Strait to help maintain the Arctic Ocean halocline. Winter darkness and inclement weather conditions have made continuous in situ and remote observation of this polynya difficult. However, imagery acquired from the European Space Agency ERS-1 Synthetic Aperture Radar (SAR) has allowed observation of the St. Lawrence Island polynya using both the imagery and derived ice displacement products. With the development of ARCSyM, a high resolution regional model of the Arctic atmosphere/sea ice system, simulation of the SLIP in a climate model is now possible. Intercomparisons between remotely sensed products and simulations can lead to additional insight into the SLIP formation process. Low resolution SAR, SSM/I and AVHRR infrared imagery for the St. Lawrence Island region are compared with the results of a model simulation for the period of 24-27 February 1992. The imagery illustrates a polynya event (polynya opening). With the northerly winds strong and consistent over several days, the coupled model captures the SLIP event with moderate accuracy. However, the introduction of a stability dependent atmosphere-ice drag coefficient, which allows feedbacks between atmospheric stability, open water, and air-ice drag, produces a more accurate simulation of the SLIP in comparison to satellite imagery. Model experiments show that the polynya event is forced primarily by changes in atmospheric circulation followed by persistent favorable conditions: ocean surface currents are found to have a small but positive impact on the simulation which is enhanced when wind forcing is weak or variable.

Meta-analysis of the association of 4 angiotensinogen polymorphisms with essential hypertension - A role beyond M235T?

Angiotensinogen (AGT) gene polymorphisms have been linked to increased risk of hypertension, but the data remain controversial. In this study we review the most commonly investigated polymorphisms at the AGT locus (other than M235T) and provide summary estimates regarding their association with essential hypertension, while addressing heterogeneity, as well as publication biases. Data on 26 818 subjects from 46 studies for the 4 most-studied AGT variants (T174M in exon 2 and 3 promoter variants: A-6G, A-20C, and G-217A) were meta-analyzed. Statistically significant associations with hypertension were identified for the T174M ( odds ratio [OR]: 1.19; 95% CI: 1.07 to 1.33; P = 0.002) and G-217A (OR: 1.37; 95% CI: 1.17 to 1.59; P = 0.00006) polymorphisms. A dual but consistent effect was observed for the -20C allele, which was associated with a decreased risk of hypertension in populations of mixed and European ancestries (OR: 0.64; 95% CI: 0.44 to 0.92; P = 0.02 and OR: 0.77; 95% CI: 0.65 to 0.91; P = 0.003, respectively), but with a 24% increase in the odds of hypertension in Asian subjects (OR: 1.24; 95% CI: 1.04 to 1.48; P = 0.02). No association of the A-6G variant with hypertension was detected. Current studies support the notion that single variants at the AGT might modulate the risk of hypertension but indicate caution in interpreting these results because of the putative presence of publication bias and gene-environment interactions.

An epidemic of violence?: Changing patterns in reported rapes in Victoria

Victoria Police statistics show that, since the late 1980s, there has been a significant increase in reported rapes in that State. One interpretation of this trend is that there has been an increase in the underlying incidence of sexual violence in the community. An alternative explanation is that rape victims have become more willing to report to the police, in response to factors such as improved provision of support services to sexual assault victims, reforms to substantive and procedural law, and changes in police attitudes and procedures. In order to rest these competing interpretations data were collected and analysed on the characteristics of rapes reported to the Victoria Police in the late 1980s/early 1990s. This analysis showed that: (I) most of the additional offences reported in the early 1990s were allegations of rapes committed by family members, spouses and other intimates; and (2) an increasing number of reports related to offences which had been committed at feast one year prior to a report being made to the police. It is argued that these changing patterns are consistent with a significant increase in the reporting rate for rape. More generally, the research reported in this paper highlights the limitations of reported crime statistics as measures of the level of social violence, and points to the need for crime researchers to develop alternative methodologies for measuring and interpreting trends.

Understanding the practical sense of health actions: contributions of Philosophical Hermeneutics

Health actions have a powerful tech no-scientific armory invested in their instrumental success. Conversely, they have a fragile conceptual basis for the understanding and transformation of the practical sense of health-disease-care processes that especifically take place nowadays. This essay intends to identify the potential contributions of philosophical hermeneutics to overcome such fragility. With this purpose and through contemporary hermeneutics, the recovery of the aristotelian distinction between theory, technique and praxis and its repercussions is discussed, for a systematic treatment of the practical reason of health actions. Against this backdrop, the following stands out: the dialogic essence of understanding-interpreting human acts; the fusion of horizons as the movement of realization of those processes of understanding; and happiness projects, existential guide to everyday life, as the impulse and the possibility of openness of the reason to the practical sense of health actions.

Effect of Disease Severity on the Performance of Cirrus Spectral-Domain OCT for Glaucoma Diagnosis

PURPOSE. To evaluate the effect of disease severity on the diagnostic accuracy of the Cirrus Optical Coherence Tomograph (Cirrus HD-OCT; Carl Zeiss Meditec, Inc., Dublin, CA) for glaucoma detection. METHODS. One hundred thirty-five glaucomatous eyes of 99 patients and 79 normal eyes of 47 control subjects were recruited from the longitudinal Diagnostic Innovations in Glaucoma Study (DIGS). The severity of the disease was graded based on the visual field index (VFI) from standard automated perimetry. Imaging of the retinal nerve fiber layer (RNFL) was obtained using the optic disc cube protocol available on the Cirrus HD-OCT. Pooled receiver operating characteristic (ROC) curves were initially obtained for each parameter of the Cirrus HD-OCT. The effect of disease severity on diagnostic performance was evaluated by fitting an ROC regression model, with VFI used as a covariate, and calculating the area under the ROC curve (AUCs) for different levels of disease severity. RESULTS. The largest pooled AUCs were for average thickness (0.892), inferior quadrant thickness (0.881), and superior quadrant thickness (0.874). Disease severity had a significant influence on the detection of glaucoma. For the average RNFL thickness parameter, AUCs were 0.962, 0.932, 0.886, and 0.822 for VFIs of 70%, 80%, 90%, and 100%, respectively. CONCLUSIONS. Disease severity had a significant effect on the diagnostic performance of the Cirrus HD-OCT and thus should be considered when interpreting results from this device and when considering the potential applications of this instrument for diagnosing glaucoma in the various clinical settings. (Invest Ophthalmol Vis Sci. 2010;51:4104-4109) DOI:10.1167/iovs.094716