bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and validation of a fluorimetric method to determine curcumin in lipid and polymeric nanocapsule suspensions
Authors: Mazzarino Letícia , Bellettini Ismael Casagrande , Minatti Edson , Lemos-Senna Elenara
Published: August 2010

A simple, rapid, and sensitive fluorimetric method was developed and validated to quantify curcumin in lipid and polymeric nanocapsule suspensions, using acetonitrile as a solvent. The excitation and emission wavelengths were set at 397 nm and 508 nm, respectively. The calibration graph was linear from 0.1 to 0.6 µg/mL with a correlation coefficient of 0.9982. The detection and quantitation limits were 0.03 and 0.10 µg/mL, respectively. The validation results confirmed that the developed method is specific, linear, accurate, and precise for its intended use. The current method was successfully applied to the evaluation of curcumin content in lipid and polymeric nanocapsule suspensions during the early stage of formulation development.
Evaluation of foam properties of saponin from Ilex paraguariensis A. St. Hil. (Aquifoliaceae) fruits
Authors: Canto Gizele Scotti do , Treter Janine , Yang Samanta , Borré Gustavo Luís , Peixoto Maria Paula Garofo , Ortega George González
Published: August 2010

Saponins are natural compounds able to form abundant foam, a desirable quality required in some chemical, foods, cosmetic and pharmaceutical processes. Ilex paraguariensis A. St. Hil. (Aquifoliaceae) known as mate, is a South American widely cultivated specie due to the preparation of a tea-like beverage from its leaves. Moreover, its green fruits are a rich source of non-toxic and very low haemolytic saponins. In this study, mate saponin fraction (MSF) was evaluated as a foam former, focusing on its foamability, foam lifetime, and film drainage in the presence of different electrolytes (ionic strength I = 0.024 M). Sodium dodecyl sulphate (SDS) and polysorbate 80 (Poly-80) were used as reference surfactants. The critical micelle concentration (CMC), the minimum attainable surface tension (γCMC), surface excess concentration (Γ) and cross-section molecular surface (A) values of MSF were comparable to those of Poly-80. The foamability of MSF and both reference surfactants was equivalent. The addition of MgCl2 resulted in a negative effect on MSF foamability. The salts NaCl, KBr, and KNO3 exhibited a negative influence on MSF foam lifetime. Similar behavior was observed for MSF film drainage (order of activity: Na2HPO4 > MgCl2 ≈ NaCl ≈ KNO3 > KBr), where a primary fast film drainage rate was followed by film thinning stabilization after around 5 min. The behavior described above seems to be uncorrelated to the solutions' zeta potential.
Methods of acute biological assays in guinea-pigs for the study of toxicity and innocuity of drugs and chemicals
Authors: Ko Gui Mi , Rosenkranz Adela , Bertoncini Clélia Rejane Antonio , Jurkiewicz Neide Hyppolito , Franco Mirian Ghiraldini , Jurkiewicz Aron
Published: August 2010

In this study, 602 samples were tested by the following assays performed at the animal facilities (Cedeme) of the Federal University of São Paulo (UNIFESP): 385 for dermal irritability, 90 for ocular irritability (discontinued in 1995), 31 for systemic toxicity by injection, 26 for oral acute toxicity, 15 for toxicity by intracutaneous injection, 15 for skin sensitization, 15 for toxicity of serum and vaccines for human use, 14 for toxicity by intramuscular implantation, 7 for pyrogens, 2 for acute dermal toxicity, and 2 for irritation of mucous membrane. The following agents were tested: cosmetics and related substances (42.0%), chemicals used in industry (32.9%), plastics, rubber, and other polymers (15.9%), agrotoxics (4.0%), medicines (2.7%), and vaccines (2.5%). In the present description, emphasis was given to tests of dermal irritability and sensitization. This work was conducted entirely in animal facilities, according to our general belief that animal facilities at universities, while considering ethic principles and sanitary, genetic, nutritional, and pathophysiological controls, also require laboratories specialized in areas such as transgenics, cryopreservation, ambiental physiology, functional genomics, alternative models, and mainly activities and research on methods in toxicology, as focused in this study.
Factors associated to antidepressant prescription for civil servants of Belo Horizonte, MG
Authors: Hurtado Renato Lopes , Magalhães Sérgia Maria Starling , Ribeiro Andréia Queiroz , Silveira Micheline Rosa da
Published: August 2010

Selecting the most suitable drug for the treatment of depression has clinical and economic implications, since both safety and cost of antidepressants (AD) vary among therapeutic subgroups. This study aimed to evaluate the prescription of antidepressants for users of the pharmacy for civil servants of PBH (FARMASERV) in 2005. Univariate, bivariate and multivariate analyzes using logistic regression were performed. Of the total prescriptions analyzed (652), the majority were for women (81.7%) and individuals aged between 19 and 59 years (81.7%). The variables independently associated with the selection of AD were gender, age and the specialty of the prescriber. Women and young adults were more likely to be prescribed an SSRI compared to their congeners, with statistically significant differences. Psychiatrists were more likely to prescribe an SSRI than neurologists or general physicians. The determinant factors for selecting antidepressants may aid the planning of interventions aimed at patients and prescribers which can enable rationalization of the use of antidepressants.
Comparação de duas técnicas radiográficas extrabucais utilizadas para avaliação do espaço aéreo nasofaringeano
Authors: Galvão Mariana de Aguiar Bulhões , Almeida Marco Antonio de Oliveira
Published: August 2010

OBJETIVO: esta pesquisa teve por objetivo comparar a utilização da radiografia cefalométrica de perfil e da radiografia de cavum na avaliação do espaço aéreo nasofaringeano. MÉTODOS: o estudo foi realizado em 2005 na cidade de Recife/PE, com um grupo de 36 crianças portadoras de respiração bucal, com idades variando de 5 a 12 anos. As crianças selecionadas foram divididas em 6 grupos e, em cada grupo, as tomadas radiográficas foram realizadas em um mesmo dia. A amostra constou de 72 radiografias, 36 cefalométricas de perfil e 36 de cavum. O laudo radiográfico foi baseado no método de Schulhof e, no final do laudo, foi emitido um Índice que representava uma síntese de todas as medidas avaliadas. RESULTADOS: os resultados foram comparados estatisticamente através do teste t de Student pareado, do teste qui-quadrado (X²), do coeficiente de correlação linear de Pearson e do índice Kappa. Apenas na porcentagem da via aérea foi encontrada diferença estatisticamente significativa (p = 0,006). Um alto grau de correlação foi verificado em todas as medidas avaliadas e o grau de concordância dos valores obtidos no Índice foi considerado bom. CONCLUSÃO: concluiu-se que a radiografia cefalométrica de perfil e a radiografia de cavum podem ser utilizadas para a análise do espaço aéreo nasofaringeano.
Modeling Runoff Generation in a Small Snow‐Dominated Mountainous Catchment
Authors: Kelleners T. J. , Chandler D. G. , McNamara J. P. , Gribb M. M. , Seyfried M. S.
Published: August 2010

Snowmelt in mountainous areas is an important contributor to river water flows in the western United States. We developed a distributed model that calculates solar radiation, canopy energy balance, surface energy balance, snow pack dynamics, soil water flow, snow–soil–bedrock heat exchange, soil water freezing, and lateral surface and subsurface water flow. The model was applied to describe runoff generation in a subcatchment of the Dry Creek Experimental Watershed near Boise, ID. Calibration was achieved by optimizing the soil water field capacity (a trigger for lateral subsurface flow), lateral saturated soil hydraulic conductivity, and vertical saturated hydraulic conductivity of the bedrock. Validation results show that the model can successfully calculate snow dynamics, soil water content, and soil temperature. Modeled streamflow for the validation period was underestimated by 53%. The timing of the streamflow was captured reasonably well (modeling efficiency was 0.48 for the validation period). The model calculations suggest that 50 to 53% of the yearly incoming precipitation in the subcatchment is consumed by evapotranspiration. The model results further suggest that 34 to 36% of the incoming precipitation is transformed into deep percolation into the bedrock, while only 11 to 16% is transformed into streamflow.
Determining Soil–Tree–Grass Relationships in a California Oak Savanna Using Eco‐Geophysics
Authors: Robinson David A. , Lebron Inma , Querejeta José Ignacio
Published: August 2010

Savanna ecosystems have long fascinated ecologists due to the codominance of trees and grasses. This codominance is often explained by the vertical juxtaposition of rooting depths leading to niche separation for water uptake. The tree–grass spatial patterns observed are often investigated within the competition, disturbance, and resource heterogeneity framework. Ecohydrologic studies are developing models to describe patterns based on this framework and the complex interplay between climate, soil moisture, and resource heterogeneity. A common impediment to unraveling the relative importance of each of these factors is a lack of detailed spatial and temporal data describing resource heterogeneity. In this research, we investigated the use of electromagnetic‐induction (EMI) imaging as a way of determining soil spatial resource heterogeneity. The aim was to determine if EMI signal response, reflecting soil texture and moisture, can provide a rapid method for identifying soil spatial resource heterogeneity, thus providing a novel method to help differentiate between the importance of competition, disturbance, and resource heterogeneity in controlling tree–grass pattern development. We found a significant difference (t= 10.18,P= 1.57 × 10−21) between signal response under grass and trees. Higher bulk soil electrical conductivity (ECa) values occurred under grass (∼32 mS m−1), indicating more clay, while lower ECa values (∼21 mS m−1) occurred under trees where clay content was less. Significant ECa differences were also observed between the oak (Quercusspp.) and buckeye [Aesculus californica(Spach) Nutt.] tree communities, but not between the evergreen and deciduous oak communities. Soil ECa provides a rapid measurement method to identify soil resource heterogeneity in savanna tree–grass systems and could provide a vital tool for woodland restoration planning.
Potential Impact of a Seepage Face on Solute Transport to a Pumping Well
Authors: Yakirevich A. , Gish T.J. , Šimunek J. , van Genuchten M.Th. , Pachepsky Y.A. , Nicholson T.J. , Cady R. E.
Published: August 2010

To develop predictive models for solute transport in the subsurface, the mechanisms governing transport must be understood and quantified. In this study, we used the HYDRUS‐2D variably saturated flow and transport model to describe the observed mass flux breakthrough curves (BTCs) of three surface‐applied tracers—Br−, Cl−, and pentafluorobenzoic acid (PFBA)—to a single well from which the tracers were pumped. Axisymmetrical transport simulations of the data indicated the presence of an active seepage face along the soil–well interface near the water table. The calculated cumulative water flux to the well through the seepage face was found to be 120% of the variable flux boundary into the well through the submerged zone. In addition, calculated mass fluxes of Br, Cl, and PFBA through the seepage interface were approximately 8, 4, and 11 times, respectively, those through the variable flux boundary. Calculations suggest that a seepage face may be responsible for causing the early arrival of the solutes and the overall shape of the BTCs. Our study indicates the potentially important role a seepage face along the soil–well interface may have in modeling water flow and chemical transport to wells in variably saturated, unconfined aquifers.
The Transition between Sharp and Diffusive Wetting Fronts as a Function of Imbibing Fluid Properties
Authors: Aminzadeh Behdad , DiCarlo David A.
Published: August 2010

The efficiency of one fluid displacing another in a permeable medium depends on the pore‐scale dynamics at the main wetting front. Experiments have shown that the frontal dynamics can result in two different flow regimes: a sharp and a diffuse front. In the sharp front regime, the displacing fluid occupies nearly all the pores and throats behind the main wetting front and the saturation changes abruptly. In contrast, in the diffuse front regime, pores are filled gradually at the main wetting front, and the saturation change is gradual in space. The different fronts can greatly alter the relative permeability curves, the trapping mechanisms, and the displacement efficiency. Directly measuring the sharpness of the front is difficult. Instead, we correlated the front sharpness to saturation overshoot, which occurs for moderate‐ to high‐flux vertical displacements of low‐density fluid by a higher density fluid in one‐dimensional, homogenous, permeable media. We hypothesized that the sharpness of wetting front can be explained by competition between two different pore‐filling mechanisms (called snap off and piston like), with the competition controlled by the velocity of the front and thus the injected flux. We conducted a series of infiltration experiments to determine the saturation profile as a function of flux for seven different fluids. We found that for each fluid there is a flux (called overshoot flux) below which saturation overshoot ceases and the front is diffuse. We found that the overshoot flux depends inversely on the invading fluid's viscosity and shows little or no dependence on the invading fluid's surface tension, vapor pressure, or miscibility with water.
Significance of Dynamic Effect in Capillarity during Drainage Experiments in Layered Porous Media
Authors: Fučík Radek , Mikyška Jiří , Sakaki Toshihiro , Beneš Michal , Illangasekare Tissa H.
Published: August 2010

We developed one‐dimensional, fully implicit numerical scheme to investigate the dynamic effect in the capillary pressure–saturation relationship used in the modeling of two‐phase flow in porous media. Its validity was investigated by means of semianalytical solutions developed by McWhorter and Sunada (1990) and the authors. The numerical scheme was used to simulate a drainage experiment where the sand and fluid properties were known. Then the numerical scheme was used to simulate a laboratory experiment in a homogeneous column, including three major models of the dynamic effect coefficient τ. This numerical scheme can handle porous medium heterogeneity and was used to simulate a fictitious experimental setup with two different sands. As a result, the penetration time of the air phase through a layered porous medium for models including dynamic effects varied between 50 and 150% compared with static models of the capillary pressure–saturation relationship. Additionally, the accumulation time of air at a material interface (i.e., the delay of the air at the interface due to the capillary barrier effect) was investigated as a function of the ratio between the air‐entry pressure values of the adjacent sands, emphasizing the differences between the dynamic and static capillary pressure models.
On the Diurnal Soil Water Content Dynamics during Evaporation using Dielectric Methods
Authors: Assouline S. , Narkis K. , Tyler S.W. , Lunati I. , Parlange M.B. , Selker J. S.
Published: August 2010

The water content dynamics in the upper soil surface during evaporation is a key element in land–atmosphere exchanges. Previous experimental studies have suggested that the soil water content increases at the depth of 5 to 15 cm below the soil surface during evaporation, while the layer in the immediate vicinity of the soil surface is drying. In this study, the dynamics of water content profiles exposed to solar radiative forcing was monitored at a high temporal resolution using dielectric methods both in the presence and absence of evaporation. A 4‐d comparison of reported moisture content in coarse sand in covered and uncovered buckets using a commercial dielectric‐based probe (70 MHz ECH2O‐5TE, Decagon Devices, Pullman, WA) and the standard 1‐GHz time domain reflectometry method. Both sensors reported a positive correlation between temperature and water content in the 5‐ to 10‐cm depth, most pronounced in the morning during heating and in the afternoon during cooling. Such positive correlation might have a physical origin induced by evaporation at the surface and redistribution due to liquid water fluxes resulting from the temperature‐gradient dynamics within the sand profile at those depths. Our experimental data suggest that the combined effect of surface evaporation and temperature‐gradient dynamics should be considered to analyze experimental soil water profiles. Additional effects related to the frequency of operation and to protocols for temperature compensation of the dielectric sensors may also affect the probes' response during large temperature changes.
Two‐Region Model for Soil Water Repellency as a Function of Matric Potential and Water Content
Authors: Karunarathna Anurudda Kumara , Moldrup Per , Kawamoto Ken , de Jonge Lis Wollesen , Komatsu Toshiko
Published: August 2010

Soil water repellency (WR) occurs worldwide and affects hydrologic processes such as infiltration, preferential flow, and surface erosion. The degree of WR varies with soil organic C (SOC) and water contents. In this study, we measured WR (by ethanol molarity) as a function of moisture conditions for two soil profiles (17 layers, of which 13 exhibited WR), representing different vegetation and SOC between 0.6 and 14%. Generally, WR was found at SOC ≥2%. Based on measured data, a two‐region water repellency (TRWR) model was developed. The model assumes two linear regions in a WR vs. pF (=log[−ψ], where ψ is the soil water matric potential in centimeters of H2O) plot, with linear increase in WR from the moisture content where WR first occurs during drying to the maximum WR at pFWR‐max, and a linear decrease from pFWR‐max until ambient air‐dried conditions. The van Genuchten soil water retention model was used to convert WR–θ (where θ is the volumetric water content) to WR–pF. The TRWR model fitting parameters, slopes, and intercepts, were all highly correlated with SOC (R2 > 0.8). The TRWR model was tested against an independent data set for five soils with 2 to 12% SOC and predicted well the measured WR–θ and WR–pF relations. For high‐SOC surface soils, the TRWR model seems promising to predict WR from fully wettable to ambient air‐dried conditions, i.e., within the interval where WR‐induced fingered water flow probably occurs. Finally, our data imply that clay saturation by SOC (quantified by the so‐called Dexter index) is useful for predicting if soils are likely to exhibit WR.
Modeling of Nonequilibrium Bromide Transport through Alluvial Gravel Vadose Zones
Authors: Dann R. , Bidwell V. , Thomas S. , Wöhling T. , Close M.
Published: August 2010

Understanding solute transport and flux through the vadose zone is important for predicting potential contaminant loading to groundwater systems. Two dual‐permeability models: mixing cell (MC) and HYDRUS 1D (H1DDP) were used to simulate long‐term nonequilibrium Br− leaching using data derived from suction cup samples at two field sites (sampled to 7‐ and 4‐m depths) on the Canterbury Plains, New Zealand. Effective model parameters were derived by inverse methods to represent average transport processes through the heterogeneous profiles. Suction cup samples indicated rapid initial movement of solute through the profiles followed by a long tail. The “management type” MC model results were comparable to the more complex HYDRUS model, providing similar overall fits to the observed data (similar RMSE ∼ 0.05–0.1). Modeling indicated that macropore flux was significant in transporting solute through the profile (MC range 5–59%; H1DDP range 15–54% of total fluxes) and simulations of cumulative fluxes from both models were similar. The MC model results indicated macropore transporting water contents of ∼0.003 (v/v) and matrix domain transporting water contents of around 0.1 to 0.15 (v/v) for the two field sites. These estimates suggest that only 3 mm of bulk drainage is required to transport solutes 1 m through the macropore domain, whereas approximately 100 to 150 mm of drainage is required to transport solutes the same distance through the matrix domain. More accurate representation of boundary conditions, texture spatial distributions, and hydraulic interactions is important for obtaining a better understanding of flux dynamics in future studies.
Characteristics of Elastic Waves According to Cementation of Dissolved Salt
Authors: Truong Q. Hung , Eom Yong-Hun , Byun Yong-Hoon , Lee Jong-Sub
Published: August 2010

Natural cementation influences the mechanical behavior of granular media. The goal of this study was to investigate the phenomenon of the low strain stiffness of granular media during precipitation and cementation of dissolved salt in the pore fluid. Granular specimens of glass beads with three different sizes (0.26, 0.5, and 1.29 mm) were cemented by NaCl aqueous solutions (0, 0.1, 0.50, 1.0, and 2.0 mol L−1). The small‐strain stiffness was investigated by measuring compressional (P) and shear (S) waves using bender elements and piezo disk elements during the cementation process. The change of P‐ and S‐wave velocities during cementation due to drying shows three distinct stages based on the degree of saturation, S: (i) S‐wave velocity increases, but P‐wave velocity decreases at a degree of saturation of 100 to ∼90%; (ii) the elastic wave velocities are stable at 90 to ∼10% saturation; and (iii) the elastic wave velocities dramatically change (increase and decrease) at a degree of saturation of 10 to ∼0% due to salt cementation and capillary force. Without cementation, the three grain size particles are controlled by capillary forces. The cementation occurs at contact points of particles for low salt concentrations and at both pores and contact points for high salt concentrations. The measured small‐strain stiffness agreed with the predicted stiffness based on the micromechanical model. This study demonstrates the elastic wave characteristics of granular media in a vadose zone according to the cementation of dissolved salt.
Foam Delivery of Amendments for Vadose Zone Remediation: Propagation Performance in Unsaturated Sediments
Authors: Zhong Lirong , Szecsody Jim E. , Zhang Fred , Mattigod Shas V.
Published: August 2010

Foam delivery of remedial amendments is potentially useful for vadose zone remediation because aqueous amendments are delivered while a low water content is maintained in the treated zones. The transport behavior of foam in the vadose zone has not been well studied. Benchtop‐scale column tests were conducted to investigate foam transport, foaming gas and liquid propagation, pressure buildup and distribution, the influence of foam quality and sediment permeability on foam injection pressure, and liquid uptake and distribution during foam flow in unsaturated sediments. Results indicated that under unsaturated conditions, the foaming gas front traveled much faster than the foam front where bubble rupture was significant. A liquid front was formed ahead of the foam flow front. The accumulated liquid in this front was mainly composed of the water injected with the foam. The foam injection pressure was primarily attributed to the resistance to foam flow by the sediment but not to the movement of the water ahead of the foam front. The foam had a high effective viscosity compared with water. A near‐linear pressure distribution within the foam‐occupied column section was observed. At a fixed injection rate, higher foam quality resulted in lower injection pressure. Higher permeability sediments did not necessarily have a lower foam injection pressure because other factors, such as the foam injection rate, foam bubble diameter, and sediment pore size, also influenced the pressure. In the foam flushed region, the liquid uptake and water content distribution in the sediment was negligibly affected by the initial water content and the foam injection rate within the ranges tested in this study. The implications of these findings to field remediation application were considered.
Use of a Combined Penetrometer–Moisture Probe Together with Geophysical Methods to Survey Hydrological Properties of a Natural Slope
Authors: Yamakawa Yosuke , Kosugi Ken'ichirou , Masaoka Naoya , Tada Yasuyuki , Mizuyama Takahisa
Published: August 2010

A newly developed, combined penetrometer–moisture probe (CPMP), together with two conventional geophysical methods, electrical resistivity imaging (ERI) and ground‐penetrating radar (GPR), was used to determine soil depth, soil type, and water distribution of a forested slope underlain by granitic bedrock. Profiles of volumetric water content (θ) measured using the CPMP accurately depicted alternations of sandy, loamy, and gravelly layers above the water table. In most cases soil–bedrock interfaces were successfully detected by ERI because of the high contrast between the electrical resistivity of dry surface soil and lightly weathered bedrock. In some areas, the soil–bedrock interface was obscured by the presence of pore water or by heavily weathered bedrock. Although a good match was obtained between θ, as directly measured using the CPMP, and θ estimated from electrical resistivity (ρ), as measured with ERI, the CPMP was more accurate than ERI for detecting heterogeneous θ distributions caused by alternations of sandy, loamy, and gravelly soil layers. Using the CPMP and ERI together is effective in quantifying soil depth, soil material, and water content distribution on a forested slope. Although soil thickness, distribution, and groundwater depth were not successfully detected using GPR on the forested slope studied, it may be possible to achieve quantitative estimates of the soil thickness and water table by calibrating GPR data with CPMP data obtained from the same locality at the same time.
Upscaling Transport of Adsorbing Solutes in Porous Media: Pore‐Network Modeling
Authors: Raoof Amir , Hassanizadeh S. Majid , Leijnse Anton
Published: August 2010

The main objective of this research was to enhance our understanding of and obtain quantitative relation between Darcy‐scale adsorption parameters and pore‐scale flow and adsorption parameters, using a three‐dimensional multidirectional pore‐network model. This helps to scale up from a simplified but reasonable representation of microscopic physics to the scale of interest in practical applications. This upscaling is performed in two stages: (i) from local scale to the effective pore scale and (ii) from effective pore scale to the scale of a core. The first stage of this upscaling from local scale to effective pore scale has been reported in an earlier manuscript. There, we found relationships between local‐scale parameters (such as equilibrium adsorption coefficient, kd, and Peclet number, Pe) and effective parameters (such as attachment coefficient, katt, and detachment coefficient, kdet). Here, we perform upscaling by means of a three‐dimensional multidirectional network model, which is composed of a large number of interconnected pore bodies (represented by spheres) and pore throats (represented by tubes). Upscaled transport parameters are obtained by fitting the solution of classical advectiondispersion equation with adsorption to the average concentration breakthrough curves at the outlet of the pore network. This procedure has resulted in relationships for upscaled adsorption parameters in terms of the microscale adsorption coefficient and flow velocity.
Bromide Adsorption by Reference Minerals and Soils
Authors: Goldberg Sabine , J. Kabengi Nadine
Published: August 2010

Bromide, Br−, adsorption behavior was investigated on amorphous Al and Fe oxide, montmorillonite, kaolinite, and temperate and tropical soils. Bromide adsorption decreased with increasing solution pH with minimal adsorption occurring above pH 7. Bromide adsorption was higher for amorphous oxides than for clay minerals. Shifts in point of zero charge (PZC) were observed on amorphous Al and Fe oxide following Br−adsorption, suggesting an inner‐sphere adsorption mechanism for Br−on these surfaces. Ionic strength effects indicated an inner‐sphere adsorption mechanism for Br−on kaolinite and an outer‐sphere adsorption mechanism on amorphous Fe oxide. Two chemical surface complexation models, the constant capacitance model and the triple layer model, were able to describe Br−adsorption as a function of solution pH on all materials. For the oxides and clay minerals and most of the soils the fit of the constant capacitance model, containing an inner‐sphere adsorption mechanism, was improved over that of the triple layer model, containing an outer‐sphere adsorption mechanism, as measured by the overall variance,VYBromide adsorption on amorphous Fe oxide as a function of solution pH and solution ionic strength was well described using the triple layer model. Our results indicate that Br−would most likely not act as a conservative tracer at soil solution pH values below 7. Therefore, we suggest that researchers carefully evaluate the pH regime and mineralogy of their study site before assuming that Br−can be applied as a conservative tracer for transport experiments.
Presidential Rhetoric and Policy Outcomes: The President and the American Struggle with Heroin Abuse
Authors: Denis Philip , Whitford Andrew B
Published: August 2010

Using data from public statements of American presidents, we describe how much attention presidents have given to treatment as a solution to the perceived problem of increasing use of narcotics in society. The data show that treatment got the most attention during the late 1960s and early 1970s. More generally, as a solution to the problem, emphasis on treatment appears to rise during periods of high drug use and fall during years of declining use.
Delivery of a Model HIV Prevention and Health Promotion Train‐the‐Trainer Program in India by Homeopathy and Ayurveda Practitioners and Educators
Authors: Nyamathi Adeline , Khurana Anil , Singh Vijay Pal , Shrikanth N. , Taneja Divya , Choudhury Shonali M. , Fahey John L. , Nayak C.
Published: August 2010

Purpose: To evaluate the effectiveness of a one‐day and three‐day train‐the‐trainer HIV/AIDS program delivered to homeopathy and ayurveda practitioners and educators. Introduction: The purpose of the training was to assess (a) the change in knowledge of and attitudes regarding HIV/AIDS at three and six months following the training, and (b) the number of secondary trainees trained by the primary trainees. Methods: Participants included 202 physicians of homeopathy and ayurveda in northern India. A total of 96 physicians of homeopathy and ayurveda were trained as primary trainees in the one‐day program, and 106 were trained in the three‐day program. Knowledge of and attitudes toward HIV/AIDS were measured by a modified 21‐item questionnaire. The one‐day training program covered epidemiology of the disease, transmission, and clinical presentation with a case‐study approach. The three‐day training added the social, ethical, and legal impact of being HIV‐infected along with health counselor and participant role plays. Results: Findings revealed that both the one‐day and three‐day primary trainees significantly increased their HIV/AIDS knowledge and attitude scores from pretest to immediate posttest with ongoing improvement in both groups over the three‐ and six‐month period. A total of 26% of primary trainees in the one‐day program trained secondary trainees, and 36% of primary trainees in the three‐day program trained secondary trainees. Conclusions: A train‐the‐trainer approach can improve the knowledge and attitude scores of ayurveda and homeopathy practitioners and educators as well as increase the number of secondary trainees. Increasing the number of trained providers to reinforce HIV prevention messages has policy implications for the Indian System of Medicine, which serves nearly 2.5 million HIV‐infected patients.
State Infertility Insurance Law Indicators
Authors: Stabile Bonnie B.
Published: August 2010

Since the birth of the first “test tube baby” in 1978, infertility treatment has gone from being seen as a scary and socially disruptive technology to a mainstream medical practice that ought to be routinely covered by medical insurance. A multivariate logistic regression model was used to identify factors associated with the adoption of infertility insurance laws in the United States. Findings suggest that the requirement for infertility insurance coverage at the state level is associated with a lower percentage of Republican state legislators and more liberal policy preferences overall. The percentage of female state legislators, and females in the labor force as a percentage of the state population, were also investigated and found not to be significant. As the costs of infertility treatment continue to be burdensome for citizens, the question of whether insurers should be required to either provide or offer coverage is likely to recur, and remains unresolved in most states. Identifying factors that are associated with the establishment of infertility insurance laws may help inform the policy process as the issue continues to be raised both in state legislatures and as a federal policy initiative.
The Continuing Importance of the Declaration of Helsinki
Authors: Brody Baruch A
Published: August 2010

The Helsinki Declaration, adopted in 1964, became a landmark document for research ethics and for the protection of human subjects. Since then, additional complexities have emerged. The advance in biomedical research protocols and medical technologies dictates further discussion of the emerging concerns in this field. This article explores the following concerns related to research with no consent given in advance, using incompetent subjects, international participation, and the role of independent research committees.
Determination of catechin and epicatechin in the peel of apple varieties resistant and non-resistant to apple scab
Authors: Gołębiowski Marek , Maliński Edmund , Szankin Małgorzata , Marszeniuk Mariusz , Paszkiewicz Monika , Stepnowski Piotr
Published: August 2010

Catechin and epicatechin were analysed in the peel of six apple cultivars (three resistant and three non-resistant to apple scab). Two methods of analytical sample preparation following extraction were tested: solid phase extraction and column separation with Sephadex LH-20 coupled to a differential refractometric detector. Prior to GC and GC-MS analyses, these compounds were silylized. This permitted co-injection with standards and the comparison of retention values and mass spectra with those recorded for standards. The content of catechin and epicatechin in apple peel is discussed in relation to the resistance of apple trees to scab.
Synthesis of methyl acetoacetate from acetone and dimethyl carbonate with alkali-promoted MgO catalysts
Authors: Wu Dudu , Chen Zhi
Published: August 2010

The synthesis of methyl acetoacetate (MAA) by methoxycarbonylation of acetone with dimethyl carbonate (DMC) was carried out in the presence of MgO and alkali-promoted MgO catalysts. From among Li, Na, K, and Cs, potassium was found to be the most effective promoter to improve the activity of MgO. The effect of K/MgO with variable content of K was also investigated, and the individual catalysts were characterised by the XRD, BET, SEM, CO2-TPD, and in situ CO2 IR techniques. The results showed that the addition of a small amount of K (1.97 mass %) could promote MAA formation, but a higher K loading caused a decrease in the yield of MAA, which might result from particle agglomeration and the presence of stable potassium carbonates. In situ FTIR experiments of co-adsorbed reactants indicated that the reaction probably proceeded via abstraction of Hα from acetone by base sites.
The First Evidence of Familial Lung Cancer in Latvia by Population Screening for Hereditary Cancer
Authors: Vanags Andrejs , Grushina Jelena , Strumfa Ilze , Gardovskis Janis
Published: August 2010

The First Evidence of Familial Lung Cancer in Latvia by Population Screening for Hereditary Cancer

Introduction. Lung cancer is the major worldwide cause of tumour lethality. Recently, the role of heredity in lung carcinogenesis has become an important scientific target. While there is ongoing search for the respective gene mutations, it was suggested that presence of at least 2 first-degree relatives with lung cancer should reveal the familial lung cancer. Aim of the study. We present the first documented evidence of familial lung cancer in Latvia by population screening data in order to improve the planning of early cancer diagnostics. Materials and methods. The investigation was designed as population screening for hereditary cancer. Family cancer history was obtained from 18642 adults in the Valka district (76.6% of the adult population). Data analysis and proband consultations were performed in Hereditary Cancer Institute. Hereditary cancer syndromes were diagnosed by clinical criteria. Results. Familial lung cancer syndrome was diagnosed in 13 probands, but suspected familial lung cancer syndrome (sFLC) - in 93 probands, corresponding to the frequency 0.6% (95% confidence interval (CI) = 0.5-0.7%). The frequency of lung cancer among blood relatives was 25.5% (95% CI = 19.3-32.8%) in definitive and 17.2% (95% CI = 15.0-19.7%) in suspected syndrome groups exceeding significantly the cumulative risk for EU population. Number of affected generations was significant for sFLC. The age of cancer onset did not influence the frequency of cancer. The data about the cancer course are described. Conclusions. The high frequency of lung cancer in the identified pedigrees supports the role of familial factors in the lung carcinogenesis as well as the practical value of our diagnostic criteria helping to identify high-risk group for intervention measures to prevent lung cancer.
First Experience in Quality of Life Analysis After Bariatric Surgery
Authors: Ozolins Arturs , Pavars Maris , Gardovskis Janis
Published: August 2010

First Experience in Quality of Life Analysis After Bariatric Surgery

Introduction. The prevalence of obesity has increased markedly in the past 20 years therefore, bariatric surgery plays an important role in obesity treatment. Aim of the study. The aim of this study was to evaluate the efficacy of Laparoscopic adjustable gastric banding (LAGB) and it influence on patients' quality of life (QOL) in the management of morbid obesity. Materials and methods. 18 patients with morbid obesity underwent LAGB procedure at the Paul Stradins Clinical University Hospital, Riga, Latvia. Data collected were: age, sex, weight, height and operation time, body mass index (BMI), excessive body weight (EBW) and comorbidities. Patients fulfilled general Short Form Health Survey with 36 questions before operation (a), 6 month (b) and 12 month (c) after operation. License was acquired for SF-36v2® use in the study. Results. The mean ± SD age of patients was 42.5 ± 11.8 years (25-63) with 83.3% of them female. The mean ± SD weight was 133.7 ± 20.3 kg (104-176), mean ± SD height 168.7 ± 9.4 cm (155-189) and mean BMI 46.2 ± 6.6 kg/m2 (36.8-58.8). The mean ± SD weight at 6 month follow up was 113.5 ± 17.8 kg (p=0.001). The postoperative mean BMI at 6 month follow up was 39.32 ± 6.1 kg/m2 (p=0.001). The mean percentage of excessive body weight (EBW) loss at 6 months was 30.4%. QOL life was higher after operation (b, c) comparing to preoperative data (a), but there were no statistically significant difference in any of the scales Conclusions. The efficacy of LAGB surgery in long-term is still uncertain, but our early results are comparable to other series. To determine the true efficacy of LAGB in weight control and impact on QOL, a longer follow-up period is necessary, more cases to analyze and data from control group of general population. Our findings suggest that life quality questionnaire SF-36v2® is good tool to measure patient's quality of life before and after operation, to discuss effectiveness of operations techniques and to observe quality of life dynamics.
The role of biopsy in differential diagnostics of kidney graft pathology
Authors: Suhorukovs Vadims , Tihomirova Tatjana
Published: August 2010

The role of biopsy in differential diagnostics of kidney graft pathology

Introduction. Different pathological changes of kidney transplants have similar symptoms, thus differential diagnostic is sometime difficult. The important information that may help to set correct diagnose can be obtained from the kidney transplant biopsy followed by pathohistological investigation. Aim of the study. The aim of this study is to demonstrate the role of biopsy in differential diagnostics of kidney graft pathology. Materials and methods. 109 kidney graft biopsies were performed at the Latvian Transplantation Centre in 2007: 20 were protocol biopsies and 89 were performed according to indications (graft dysfunction). All biopsies were performed under USS control followed by pathohistological investigations of the material obtained. Morphological changes were evaluated accordingly to the Banff 97 classification. Results. The morphological findings were as follows: borderline changes - 8 cases (7.34%); acute cellular rejection - 80 cases (73.4%); acute humoral rejection - 1 case (0,92%); hronic graft nephropathy - 27 cases (24.8%); tubolointersticial nephritis - 36 cases (33%); apostematous nephritis - 1 case (0.92%). We observed mild hematuria in only 2 patients after biopsy which stopped spontaneously in a few days. Conclusions. Kidney graft biopsy followed by pathohistological investigation of the material obtained is a precise and sensitive method in the diagnostic process of pathological changes of the graft with a small rate of complication.
Intraabdominal Pressure in Children After Cardiothoracic Surgery
Authors: Krastins Jekabs , Straume Zane , Auzins Janis
Published: August 2010

Intraabdominal Pressure in Children After Cardiothoracic Surgery

Introduction. Intraabdominal pressure (IAP) now is widely recognized as an important variable and its monitoring is used in a variety of critically ill patients. Aim of the study. The aim of this study was to measure and to recognize the influence of various factors on IAP in children after surgical correction of congenital heart disease. Materials and methods. We conducted non-randomized, prospective observational study in Pediatric intensive care unitat a University Children's hospital. Study protocol was approved by Hospital Ethics commision. Measurements of IAP were performed in 15 children with mean body weight 8±5,83 kg, (Range 3,1-28 kg), mean age of 18,01 months (range 8 days-8 years) after cardiothoracic surgery. Cardiopulmonary bypass (CPB) was used in 12 patients. IAP was measured during first 24 hours postoperatively at 12 hour intervals via indwelling urinary catheter with bladder volumes of 1 ml/kg of normal saline. Of the 15 patients, 12 were mechanically ventilated at the time of the IAP measurements. Ventilation pressures: PIP (peak inspiratory pressure), MAP (mean airway pressure), PEEP (positive end expiratory pressure) and central venous pressure (CVP) via femoral vein were recorded. In some patients (6 from 15) amount of fluid evacuated via intraperitoneal drain from peritoneal cavity in first 24 hours was measured. Results. IAP was 12,24±3,54 mm Hg (Range 5,44-20,4 mm Hg), CVP 13±2,19, PIP 20±2,48 cm H2O, MAP 9±2,3 cm H2O, PEEP 5±1,35 cm H2O. Amount of fluid removed from peritoneal cavity during first 24 hours was 0,8±0,54 ml/kg/h (Range 0,04-1,7 ml/kg/h). Conclusions. We find elevated intraabdominal pressure (IAP> 12 mm Hg) in 10 from 15 (66,67%) pediatric patients in the first 24 hours after cardiothoracic surgery. There was a difference in IAP in patients with abdominal paracenthesis versus patients without the drain. The difference between groups was not statistically significant (P=0,4). We did not find a correlation between IAP, MAP and CVP. We, however, did not observe development of abdominal compartment syndrome (ACS).
Histomorphology of Salivary Glands after Ligature and Reconstruction of Common Carotid Artery in Rabbits
Authors: Stamers Kaspars , Pilmane Mara , Feldmane Laila , Pastars Kalvis , Tomisheva Nonna , Skagers Andrejs
Published: August 2010

Histomorphology of Salivary Glands after Ligature and Reconstruction of Common Carotid Artery in Rabbits

Introduction. In occlusive diseases of carotid arteries may be involved salivary glands which play important role in oral and general homeostasis. Aim of the study. The purpose of this study was histomorphological evaluation of rabbit's salivary glands after regional reduction af arterial circulation and reconstruction of ligated common carotid arteries comparing with normal histological sight. Materials and methods. The experiments were authorized by the Animal Ethics Committee of the Latvian Food and Veterinary Service. 20 male Californian rabbits weighing approximately 3 kg were used. Under intravenous general anesthesia and local anesthesia the ligature of a. carotis communis dextra was done. After 28 days 10 rabbits were sacrificed and samples were taken from all major salivary glands and histological measured acinar dimensions and acinar epithelial cell. For rest 10 rabbits under the general anesthesia were performed revascularization of a. carotis communis dextra. After 28 days the rabbits were sacrificed with intrapulmonal injection of T61. The acini dimensions and acinar epithelial cell diameter in microns in all glands were measured except buccal glands were measured. Results. In ischemic conditions all glands react with decrease of acinar epithelial cell diameter and also diametr of functional unit of salivary gland. After revascularisation reestablishment of acini and secretory epithelial cells was observed. Conclusions. Rabbit's salivary glands have potential to recovery in diminished after ligation of ipsilateral common carotid artery size of acini and secretory epithelium after 4 week ischemia if the blood supply is reestabilished.