Clays can act as osmotic membranes and thus give rise to osmotically induced hydrostatic pressures. The magnitude of generated osmotic pressures in geologic systems is governed by the theoretical osmotic pressure calculated solely from solution properties and by value of the membrane's three phe-nomenological coefficients: the hydraulic permeability coefficient, Lp; the reflection coefficient, σ; and the solute permeability coefficient, ω. Generally, low values of Lp correspond to highly compacted membranes in which σ is near unity and ω approaches zero. Such membrane systems should give rise to initially high osmotic fluxes and gradual dissipation of their osmotic potentials.

The high fluid pressures in the Dunbarton Triassic basin, South Carolina, are a good example of osmotically induced potentials. A unique osmotic cell is created by the juxtaposition of fresh water in the overlying Cretaceous sediments against the saline pore water housed within the membrane-functioning sediments of the Triassic basin. Because wells penetrating the saline core of the basin show anomalously high heads relative to wells penetrating the basin margins, the longevity of this osmotic cell is probably dictated by the rate at which salt diffuses out into the overlying fresh water aquifer.

The application of ceramic membranes is limited by the high cost of raw materials and the sintering process at high temperatures. To overcome these drawbacks, the present study investigated both the preparation of ceramic membranes using cost-effective raw materials and the possibility of recycling the membranes for the treatment of oily wastewater. Ceramic membranes with a pore size of 0.29–0.67 μm were prepared successfully at temperatures as low as 1000–1100°C by a simple pressing route using lowcost base materials including diatomite, kaolin, bentonite, talc, sodium borate, and barium carbonate. The typical steady-state flux, fouling resistance, and oil-rejection rate of the low-cost virgin membranes sintered at 1000°C were 2.5 × 10−5 m3m−2s−1 at 303 kPa, 63.5%, and 84.1%, respectively, with a feed oil concentration of 600 mg/L. A simple burn-out process of the used membranes at 600°C in air resulted in >95% recovery of the specific surface area (SSA) of the virgin membranes, a significantly increased steady-state flux, decreased fouling resistance, and increased oil-rejection rate. The typical steady-state flux, fouling resistance, and oil-rejection rate of the low-cost ceramic membrane sintered at 1000°C and subsequently heat treated at 600°C for 1 h in air after the first filtration were 5.4 × 10−5 m3m−2s−1 at 303 kPa, 27.1%, and 92.9%, respectively, with a feed oil concentration of 600 mg/L. The present results suggest that the low-cost ceramic membranes used for oily wastewater filtration can be recycled by simple heat-treatment at 600°C in air. As the fouling resistance of the low-cost ceramic membranes decreased with a decrease in pore size, the preferred pore size of the membranes for oily wastewater filtration is <0.4 μm.

Chemically modified bentonites are being developed with the aim of preserving low hydraulic conductivity in the presence of potentially aggressive permeants in pollutant-containment applications. ‘Multiswellable’ bentonite (MSB) has been obtained by treating standard sodium bentonite with propylene carbonate. Research on the engineering properties of MSB has focused mainly on permeability and chemical compatibility. Solute diffusion and membrane behavior in MSB have not yet been investigated. A combined chemico-osmotic/diffusion test was performed on a MSB specimen using a 5 mM CaCl2 solution. Permeability with distilled water and with the 5 mM CaCl2 solution was measured prior to and after the chemico-osmotic/diffusion tests. The material exhibited time-dependent membrane behavior with a peak osmotic efficiency value (ω) of 0.172 that gradually shifted to zero upon breakthrough of calcium ions. Effective diffusion coefficients of calcium and chloride ions were in the range commonly described for untreated bentonite at similar porosities. After the chemico-osmotic/diffusion stage and permeation with 5 mM CaCl2, the hydraulic conductivity of MSB increased from 1.1 × 10−11 m/s to 7.0 × 10−11 m/s. The MSB was apparently converted into a calcium-exchanged bentonite at the end of the test. Prehydration and subsequent permeation might have contributed to elution of the organic additive from the clay. Further investigation is recommended to clarify the effect of prehydration on the hydraulic performance of MSB in the presence of potentially aggressive permeants.

Metallic thin-film composite membranes are produced by sputtering metal films onto commercial polymer membranes. The separations capability of the membrane substrate is enhanced with the addition of a 10 nm Ta film. The addition of a tantalum layer decreases the molecular weight cutoff of the membrane from 70 kDa dextran (19 nm) to below 5 kDa (6 nm). Water flux drops from 168 LMH/bar (LMH: liters/meters2/hour) (polymer support) to 8.8 LMH/bar (Ta composite). A nanoporous layer is also added to the surface through Mg/Pd film deposition and dealloying. The resulting nanoporous Pd is a promising catalyst with a ligament size of 4.1 ± 0.9 nm. The composite membrane's ability to treat water contaminated with chlorinated organic compounds (COCs) is determined. When pressurized with hydrogen gas, the nanoporous Pd composite removes over 70% of PCB-1, a model COC, with one pass. These nanostructured films can be incorporated onto membrane supports enabling diverse reactions and separations.

Left atrial appendage membrane is a rare anomaly. Its implications on clinical course are unknown. We report the first paediatric case in association with a congenital heart disease.

Pneumonia has contributed greatly to child mortality, especially among children under the ages of five in sub-Saharan Africa, killing more children than the number of children dying from HIV/AIDS. The current methods of diagnosing pneumonia involved physical examination and chest x-ray which are limited by low accuracy, high error margins, higher cost, and stands the risks of inducing cancer. In this work, a low-cost, non-invasive biomedical device was designed and developed to improve accuracy in diagnosing pneumonia. The device functions to detect fluid in a lung consolidated by pneumonia. Dry grouting sponge was used as a phantom for a healthy lung, while a wet sponge was used to mimic a pneumonia-consolidated lung. Surface exciter was used to produce sound waves which travelled through one side of the phantom and are detected on the other end using an electronic stethoscope. The signals detected were digitally analyzed using MATLAB and AUDACITY software. The differences in resonant frequencies from the power spectrum analysis of sound waves as they travelled through the sponges were used to distinguish between a pneumonia-consolidated lung and a healthy lung.

Sarin gas is a dangerous chemical warfare agent (CWA). It is a nerve agent capable of bringing a person to death in about 15 minutes. A lethal concentration of sarin molecules in air is about 30 mg/m3. Experimental research on this gas requires very careful safety protocols for handling and storage. Therefore, theoretical and computational studies on sarin gas are very welcome and might provide important safe guides towards the management of this lethal substance. In this work, we investigated the interactions between sarin, air and nanoporous graphene, using tools of classical molecular dynamics simulations. Aiming to cast some light in the possible sarin selective filtration by graphene, we designed a bipartite simulation box with a porous graphene nanosheet placed at the middle. Sarin and air molecules were initially placed only on one side of the box so as to create an initial pressure towards the passage of both to the other side. The box dimensions were chosen so that the hole in the graphene was the only possible way through which sarin and air molecules can get to the other side of the box. The number of molecules that passed through the hole in graphene was monitored during 10 ns of simulation and the results for different temperatures were compared. The results show that, as far as the size of the holes are small, van der Waals forces between graphene and the molecules play a significant role on keeping sarin near graphene, at room temperature.

This work reports on the use of diatomaceous earth (DE) waste and organic binder derived from Corchorus olitorius, locally known as “Mrenda” in the design of an efficient water filtration membranes. Charcoal powder was incorporated to enhance the porosity of the membrane. The firing was done at temperatures varying from 700.0 °C to 1150.0 °C. The DE waste samples comprised 79.0% silica (by mass) and 11.0% total flux content compared to porter’s clay that had 50.0% silica, 28.8% AL2O3 and 7.0% total flux content. On the other hand, the “Mrenda” binder contained 6.5% total organic matter. The use of the plant-derived binder enhanced the mechanical strength of the greenware by 52.7% and the fired membranes by 152.2%. The fabricated DE waste-based membranes were 15.0% stronger than clay-based ceramic membranes prepared under similar conditions. A sintering temperature of 900.0 °C was optimal in producing porous membranes for filtering of 4.1 liters of water per hour. The pore diameter of the membranes fabricated from DE waste only ranged between 2.0 nm – 99.0 nm. On micro-organisms filtering efficacy, the DE waste-based membranes and those fabricated with 5.0% charcoal were 99.9% and 88.4% effective in the removal of E. coli and Rotavirus respectively.

The understanding of the genetic basis of grain dormancy in wheat has rapidly improved in the last few years, and a number of genes have been identified related to that trait. We recently identified the wheat genes TaPM19-A1 and -A2 and we have now taken the first step towards understanding the role of this class of genes in seeds. By investigating the Arabidopsis homologous PM19-Like 1 (PM19L1) we have found that it has a seed-specific expression pattern and, while its expression is higher in dormant than in non-dormant seeds, knock-out mutations produced seeds with increased dormancy. Not only primary dormancy, but also secondary dormancy in response to high temperature was increased by the loss-of-function. We have also examined the function of PM19L1 by localizing the PM19 protein primarily to the cotyledon cells in seeds, possibly in membranes. By investigating the co-expression network of this gene we have found that it is connected to a small group of abscisic acid (ABA)-induced seed maturation and storage-related genes. The function of PM19L1 represents a good opportunity to explore the interactions of key factors that can influence seed dormancy such as ABA, temperature and membrane properties.

Lung surfactant (LS), a thin layer of phospholipids and proteins inside the alveolus of the lung is the first biological barrier to inhaled nanoparticles (NPs). LS stabilizes and protects the alveolus during its continuous compression and expansion by fine-tuning the surface tension at the air-water interface. Previous modelling studies have reported the biophysical function of LS monolayer and its role, but many open questions regarding the consequences and interactions of airborne nano-sized particles with LS monolayer remain. In spite of gold nanoparticles (AuNPs) having a paramount role in biomedical applications, the understanding of the interactions between bare AuNPs (as pollutants) and LS monolayer components still unresolved. Continuous inhalation of NPs increases the possibility of lung ageing, reducing the normal lung functioning and promoting lung malfunction, and may induce serious lung diseases such as asthma, lung cancer, acute respiratory distress syndrome, and more. Different medical studies have shown that AuNPs can disrupt the routine lung functions of gold miners and promote respiratory diseases. In this work, coarse-grained molecular dynamics simulations are performed to gain an understanding of the interactions between bare AuNPs and LS monolayer components at the nanoscale. Different surface tensions of the monolayer are used to mimic the biological process of breathing (inhalation and exhalation). It is found that the NP affects the structure and packing of the lipids by disordering lipid tails. Overall, the analysed results suggest that bare AuNPs impede the normal biophysical function of the lung, a finding that has beneficial consequences to the potential development of treatments of various respiratory diseases.

Tactile sense provides us with the necessary information and feedback to determined tasks. Within this context, haptic devices represent a growing and highly interesting field to be included in biomedical devices, teleoperation applications, and video games. These devices are usually developed with rigid materials, motors, and mechanisms to provide tactile feedback to individuals that corresponds to a defined task, producing pressure, tangential force or vibrations as stimuli on the skin. Here, we present a prototype of a soft pneumatic haptic device based on an inflatable hyperelastic membrane, that can provide two stimuli over skin such as pression and traction with only one input of energy. The device was fabricated using different types of silicone materials and membrane shapes. This exhibits experimentally a maximum vertical deformation of 13 mm and a tangential displacement of 10 mm at 7 kPa. These two mechanically programmed movements open the possibility of using this technology in mechano-tactile feedback for wearable devices, with low-cost hardware, soft interaction between devices and skin, and lightweight.

Carboxylated carbon nanotubes (C or cCNTs) were incorporated in polyethersulfone hollow fiber membranes (P HFMs) to improve the gas separation performance, i.e., pure gas permeability and ideal gas selectivity. The developed CP HFMs showed the remarkable improvement in thermal stability and mechanical strength as compared to that of the pristine P HFMs. The pure gas permeability of CO2, CH4, O2, and N2 gases for the HFMs were measured at 3 bar feed pressure and room temperature. It was observed that the presence of cCNTs in HFMs significantly improved the CO2 and O2 permeability for CP HFMs by 10.8-and 11.7- fold, respectively, as compared to that measured for P HFMs. Furthermore, the ideal gas selectivity for CO2/CH4, O2/N2, and CO2/N2 gas pairs for CP HFMs was also remarkably enhanced by almost 8.6-, 10.7-and 9.9-times, respectively, as compared to that measured for P HFMs. CP HFMs exhibited gas separation performance better than or comparable to that of the literature-reported CNTs-based membranes. Remarkably, the gas separation performance of CP HFMs crossed Robeson’s 2008 upper bound curve for O2/N2 gas-pair and was almost closer to the upper bound curves drawn by Robeson in 2008 for CO2/CH4 and CO2/N2 gas pairs. The improved separation performance can be attributed to the presence of cCNTs in HFMs. Thus, the results obtained in this study clearly showed that the CP HFMs can potentially be used as a membrane material for the industrially relevant gas separations.

The aim of the present research was to evaluate pectin-gelatine and pectin-collagen polymeric compounds as encapsulating and releasing matrices for whey active peptides with antioxidant properties. Active peptides were obtained by hydrolysis of whey proteins with thermolysin and proteinase enzymes from B. subtilis. The hydrolysates were fractioned and encapsulated in the pectin composite matrices to obtain particles loaded with active whey peptides. The composite particles were analysed by SEM and IR techniques. In addition, they were also tested under simulated gastric conditions to evaluate the encapsulation efficiency and delivering power of the composite materials. The results showed that both encapsulation particles were excellent supports, because they retained to-the peptides and maintained their antioxidant activity during the simulated gastric process (120 min). However, the pectin gelatine particles were digested faster than those of pectin-collagen. The peptides from-encapsulated in pectin-gelatine were released within this time, showing an increment in the-antioxidant activity. Peptides from gelatine protein were also released by the gastric enzymes, and thus also they contributed to the antioxidant activity; in addition to the whey peptides.

Extracellular Matrix (ECM), a natural biomaterials, have recently garnered attention in tissue engineering for their high degree of cell proliferative capacity, biocompatibility, biodegradability, and tenability in the body. Decellularization process offers a unique approach for fabricating ECM-based natural scaffold for tissue engineering application by removing intracellular contents in a tissue that could cause any adverse host responses. The effects of Supercritical carbon dioxide (Sc-CO2) treatment on the histological and biochemical properties of the decellularized extracellular matrix (de-ECM) were evaluated and compared with de-ECM from conventional decellularization process to see if it offers significantly reduced treatment times, complete decellularization, and well preserved extracellular matrix structure. The study has shown that a novel method of using supercritical fluid extraction system indeed removed all unnecessary residues and only leaving ECM. The potential of Sc-CO2 de-ECM progressed as a promising approach in tissue repair and regeneration.

A new family of six ionenes containing aromatic amide linkages has been synthesized from ready available starting materials at scales up to ∼50 g. These ionene-polyamides are all constitutional isomers and vary only in the regiochemistry of the amide linkages (para, meta) and xylyl linkages (ortho, meta, para) which are present in the polymer backbone. This paper details the synthesis of these ionenes and associated characterizations. Ionene-polyamides exhibit relatively low melting points (∼150 oC) allowing them to be readily processed into films and other objects. These ionene-polyamide materials are being developed for further study as polymer membranes for the separations of gases such as CO2, N2, CH4 and H2.

The treatment of leishmaniasis relies primarily on highly toxic, parenterally administered drugs. Therefore, the search for more effective and safer drugs is considered a priority for leishmaniasis’ control. The antileishmanial activity of the oestrogen receptor modulator tamoxifen was previously described in experimental models of leishmaniasis. However, the mechanisms responsible for the antileishmanial activity of tamoxifen remain unknown. Since tamoxifen has been shown to affect plasma and intracellular membranes in tumour cells, the aim of this study was to investigate the activity of the drug on Leishmania amazonensis membranes. Through morphological analysis and labelling with propidium iodide and DiSBAC2(3), we demonstrated that tamoxifen led to plasma membrane depolarization without general membrane disruption or permeabilization. Tamoxifen also caused mitochondrial damage, with loss of membrane potential, as shown by Rhodamine 123 accumulation. Mitochondrial swelling followed, signalling the mitochondrial dysfunction. Therefore, the effect of tamoxifen on Leishmania is mediated, at least in part, by disorder in parasite's membranes. These alterations are sufficient to trigger a series of lethal events.

Graphene oxide (GO) and its phosphonated analogue (pGO) have been incorporated into sulfonated poly(styrene-isobutylene-styrene) (SO3H SIBS) to generate membranes with enhanced water retention. The polymer nanocomposite membranes (PNMs) were prepared per SIBS sulfonation level (i.e., 38, 61, and 90 mole %), filler type (i.e., GO and pGO) and filler loading (i.e., 0.1, 0.5 and 1.0 wt.%). FT-IR and TGA confirmed the functionalization and incorporation of the fillers into SO3H SIBS. No significant changes were observed in the thermal stability or FTIR spectra of the PNMs after addition of the fillers. Dissimilar behaviors were observed for the water absorption capabilities (i.e., swelling ratio and water uptake) after incorporation of the fillers. The nanofillers enhanced the water absorption of the sulfonated polymer, possibly due to interconnections between the ionic groups. Therefore, the PNMs could not only potentially function as proton exchange membranes (PEMs) for several applications such as direct methanol fuel cells (DMFCs).

The effect of ammonium sulfate (AMS) on efficacy and on absorption and translocation of sethoxydim in wild oats and barley was investigated under controlled environmental conditions. Increases in efficacy in the presence of AMS were relatively small. The rate of sethoxydim required to reduce dry weight 50% was reduced from 0.08 kg a.i. ha−1, for both species, to 0.07 and 0.06 kg ha−1 for wild oats and barley, respectively, in the presence of added AMS. In short-term experiments, uptake of 14C from 14C-labeled sethoxydim 0.5 and 1 h after application was increased approximately twofold with the addition of AMS. AMS had little effect on sethoxydim absorption beyond 1 h after application. Translocation at 1 h after application was unaffected by AMS. However, translocation 12 and 24 h after application was increased with AMS. It is postulated that the translocation increase results indirectly from the increase in absorption. The observed increase in absorption with the addition of AMS is evident only when crop oil concentrate (COC) is also present In model systems, the addition of AMS enhanced sorption of sethoxydim into Isolated cuticles but had no effect on movement into excised roots.

Responses of Rhizoctonia solani Kuhn to napropamide [2-(α-naphthoxy)-N,N-diethylpropionamide], were evaluated by measuring whole-cell respiration, mitochondrial respiration, ATP synthesis, and membrane leakage. Whole-cell respiration, measured with an O2 electrode, was stimulated in the presence of napropamide at 1.1, 2.2, and 4.4 × 10−5 M. Mitochondrial respiration was stimulated at 1.1 × 10−11 M, but higher concentrations were inhibitory. The addition of 10−5 M napropamide to isolated mitochondria of R. solani resulted in reduced ATP synthesis, measured by the firefly luciferase assay, and in increased membrane permeability as measured by increases in electrical conductivity of filtrates from R. solani grown in culture medium containing napropamide. These results indicate that, under laboratory conditions, napropamide reduced ATP synthesis, caused membrane leakage, and stimulated respiration in R. solani.

The chlorophyll levels and growth of oat (Avena sativa L. ‘Elgin’) seedlings were drastically reduced after foliar application of diclofop-methyl {methyl 2-[4-(2,4-dichlorophenoxy)phenoxy] propanoate}. The leaves were chlorotic and necrotic with the newly emerging leaves being most affected. Plants treated with 2,4-D [(2,4-dichlorophenoxy)acetic acid] were similar to the controls. When 2,4-D was applied to intact plants in combination with diclofop-methyl the toxicity symptoms produced by diclofop-methyl were reduced. Diclofop-methyl disrupted membrane integrity and inhibited chlorophyll formation in excised leaf segments. Addition of 2,4-D with diclofop-methyl did not change the effects produced by diclofop-methyl alone in excised leaf segments.