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Background Genome-wide DNA methylation (DNAme) profiling of the placenta with Illumina Infinium Methylation bead arrays is often used to explore the connections between in utero exposures, placental pathology, and fetal development. However, many technical and biological factors can lead to signals of DNAme variation between samples and between cohorts, and understanding and accounting for these factors is essential to ensure meaningful and replicable data analysis. Recently, “epiphenotyping” approaches have been developed whereby DNAme data can be used to impute information about phenotypic variables such as gestational age, sex, cell composition, and ancestry. These epiphenotypes offer avenues to compare phenotypic data across cohorts, and to understand how phenotypic variables relate to DNAme variability. However, the relationships between placental epiphenotyping variables and other technical and biological variables, and their application to downstream epigenome analyses, have not been well studied. Results Using DNAme data from 204 placentas across three cohorts, we applied the PlaNET R package to estimate epiphenotypes gestational age, ancestry, and cell composition in these samples. PlaNET ancestry estimates were highly correlated with independent polymorphic ancestry-informative markers, and epigenetic gestational age, on average, was estimated within 4 days of reported gestational age, underscoring the accuracy of these tools. Cell composition estimates varied both within and between cohorts, as well as over very long placental processing times. Interestingly, the ratio of cytotrophoblast to syncytiotrophoblast proportion decreased with increasing gestational age, and differed slightly by both maternal ethnicity (lower in white vs. non-white) and genetic ancestry (lower in higher probability European ancestry). The cohort of origin and cytotrophoblast proportion were the largest drivers of DNAme variation in this dataset, based on their associations with the first principal component. Conclusions This work confirms that cohort, array (technical) batch, cell type proportion, self-reported ethnicity, genetic ancestry, and biological sex are important variables to consider in any analyses of Illumina DNAme data. We further demonstrate the specific utility of epiphenotyping tools developed for use with placental DNAme data, and show that these variables (i) provide an independent check of clinically obtained data and (ii) provide a robust approach to compare variables across different datasets. Finally, we present a general framework for the processing and analysis of placental DNAme data, integrating the epiphenotype variables discussed here.

The fabrication of a composite electrospun fiber membrane with sorptive characteristics intended for removal of heavy metals was investigated. The electrospun fiber membrane was impregnated with nano-boehmite particles. The latter had been selected to increase surface area of the active component. Cd (II) was chosen as the challenge bivalent cation. The sorption capacity of the nano-boehmite was studied as a function of pH and time. Electrospinning was used to prepare the composite submicron fiber membrane impregnated with boehmite nanoparticles. The later was blended with the polymer to produce a homogenous mixture before electrospinning. Two polymers, the hydrophobic/PCL/and hydrophilic/Nylon-6/, were chosen to serve as the support for the boehmite. The nanoparticles and resulting composite membranes were characterized using SEM, TEM, and XRD techniques. XRD data confirmed the presence of nano-boehmite particles in the nanofibers membrane. The membranes so prepared were challenged with aqueous solutions of Cd in batch isotherm tests. Atomic absorption spectroscopy results show sorption of Cd (II) by boehmite impregnated electospun membrane was possible and a capacity of 0.20 mg/g was achieved.

Age-related macular degeneration (AMD) is a growing public health concern given the aging population and it is the leading cause of blindness in developed countries, affecting individuals over the age of 55 years. AMD affects the retinal pigment epithelium (RPE) and Bruch’s membrane in the macula, leading to secondary photoreceptor degeneration and eventual loss of central vision. Late AMD is divided into two forms: neovascular AMD and geographic atrophy (GA). GA accounts for around 60% of late AMD and has been the most challenging subtype to treat. Recent advances include approval of new intravitreally administered therapeutics, pegcetacoplan (Syfovre) and avacincaptad pegol (Iveric Bio), which target complement factors C3 and C5, respectively, which slow down the rate of enlargement of the area of atrophy. However, there is currently no treatment to reverse the central vision loss associated with GA. Optogenetics may provide a strategy for rescuing visual function in GA by imparting light-sensitivity to the surviving inner retina (i.e., retinal ganglion cells or bipolar cells). It takes advantage of residual inner retinal architecture to transmit visual stimuli along the visual pathway, while a wide range of photosensitive proteins are available for consideration. Herein, we review the anatomical changes in GA, discuss the suitability of optogenetic therapeutic sensors in different target cells in pre-clinical models, and consider the advantages and disadvantages of different routes of administration of therapeutic vectors.

Laundry wastewater is a major contributor to the global annual wastewater output, highlighting the importance of reusing larger volumes of the wastewater as a valuable water resource. Among the conventional wastewater, coagulation process displays promising results in treating laundry wastewater. However, studies show that the conventional chemical coagulant such as alum has been associated with health concerns. To address these drawbacks, a more environmentally friendly alternative such as natural coagulant is being explored such as Hibiscus sabdariffa due to it seed contain high protein content. This present study aims to characterize Hibiscus sabdariffa seeds and determine the optimal conditions for effectively treating laundry wastewater using Hibiscus sabdariffa as a natural coagulant. Additionally, the study compared the effectiveness of natural and chemical coagulants in this application. The studies parameter ranges include pH (2 –11) and dosages (50 – 500 mg/L). Water quality parameters such as Chemical Oxygen Demand (COD), Total Suspended Solid (TSS) and turbidity will be used to evaluate the coagulation performance. The jar test experiment was carried out and found out that natural coagulant performed best at a pH of 2 and a dosage of 100 mg/L, resulting in COD, turbidity, and TSS removal efficiencies of 32.59%, 77.98%, and 86.51% respectively, with final treated ef luent levels of 212 mg/L for COD, 11.25 NTU for turbidity, and 17 mg/L for TSS, meeting the requirements of Standard B discharge except for the COD and pH. In comparison, the alum chemical coagulant demonstrated better performance, achieving 57.96% COD removal, 95.24% turbidity removal, and over 95% TSS removal. This study successfully showed that the Hibiscus sabdariffa is capable of treating laundry wastewater, showcasing comparable performance to the chemical coagulant in removing turbidity and TSS.

Water in agricultural catchments is prone to pollution from agricultural runoff containing nutrients and pesticides, and contamination from the human population working and residing therein. This study examined the quality of water in a drainage stream which runs through a congested network of ‘line houses’ (low-income housing, typically found arranged in straight ‘lines’ on estates) in the tea estate catchment area of Pussellawa in central Sri Lanka. The study evaluated the applicability of vertical subsurface flow (VSSF) and horizontal subsurface flow (HSSF) constructed wetlands for water polishing, as the residents use the stream water for various domestic purposes with no treatment other than possibly boiling. Water flow in the stream can vary significantly over time, and so investigations were conducted at various flow conditions to identify the hydraulic loading rate (HLR) bandwidth for wetland polishing applications. Two wetland models of 8 m × 1 m × 0.6 m (length × width × depth) were constructed and arranged as VSSF and HSSF units. Stream water was diverted to these units at HLRs of 3.3, 4, 5, 10, 20, and 40 cm/day. Results showed that both VSSF and HSSF wetland units were capable of substantially reducing five-day biochemical oxygen demand (BOD5), total suspended solids (TSS), fecal coliform (FC), total coliform (TC), ammonia nitrogen (NH4+-N), and nitrate nitrogen (NO3−-N) up to 20 cm/day HLR, with removal efficiencies of more than 64%, 60%, 90%, 93%, 70%, and 59% for BOD5, TSS, FC, TC, NH4+-N, and NO3−-N, respectively, in the VSSF wetland unit; and more than 66%, 62%, 91%, 90%, 53%, and 77% for BOD5, TSS, FC, TC, NH4+-N, and NO3−-N, respectively, in the HSSF wetland unit.

The microbial communities of membrane biofilms occurring in two full-scale water purification processes employing microfiltration (MF) and reverse osmosis (RO) membranes were characterized using a polyphasic approach that employed bacterial cultivation, 16S rDNA clone library and fluorescence in situ hybridization techniques. All methods showed that the α-Proteobacteria was the largest microbial fraction in the samples, followed by the γ-Proteobacteria. This suggested that members of these two groups could be responsible for the biofouling on the membranes studied. Furthermore, the microbial community structures between the MF and RO samples were considerably different in composition of the most predominant 16S rDNA clones and bacterial isolates from the α-Proteobacteria and only shared two common groups (Bradyrhizobium, Bosea) out of more than 17 different bacterial groups observed. The MF and RO samples further contained Planctomycetes and Fibroacter/Acidobacteria as the second predominant bacterial clones, respectively, and differed in minor bacterial clones and isolates. The community structure differences were mainly attributed to differences in feed water, process configurations and operating environments, such as the pressure and hydrodynamic conditions present in the water purification systems.

Abstract The RNA F-specific coliphages, MS2 and Qβ, have been used as virus indicators in water and wastewater studies. It is therefore useful to have a good understanding concerning the effects of environmental factors on their survival in order to choose an appropriate candidate for assessing microbial safety in relation to water quality management. The effects of pH and temperature on the survival of these two coliphages were investigated. MS2 survived better in acidic conditions than in an alkaline environment. In contrast, Qβ had a better survival rate in alkaline conditions than in an acidic environment. The inactivation rates of both coliphages were lowest within the pH range 6–8 and the temperature range 5–35°C. The inactivation rates of both coliphages increased when the pH was decreased to below 6 or increased to above 8. The inactivation rates of both coliphages increased with increasing temperature. Qβ behaved peculiarly in extreme pH buffers, i.e. it was inactivated very rapidly initially when subjected to an extreme pH environment, although the inactivation rate subsequently decreased. In general, MS2 was a better indicator than Qβ. However, within the pH range 6–9 and at temperatures not above 25°C, either MS2 or Qβ could be used as a viral indicator.

Background Fluoride contamination of groundwater, both anthropogenic and natural, is a major problem worldwide and hence its removal attracted much attention to have clean aquatic systems. In the present work, removal of fluoride ions from drinking water tested using synthesized γ-Fe 2 O 3 nanoparticles. Methods Nanoparticles were synthesized in co-precipitation method. The prepared particles were first characterized by X-ray diffraction (XRD) and Transmission Electron Microscope (TEM). Density functional theory (DFT) calculations on molecular cluster were used to model infrared (IR) vibrational frequencies and inter atomic distances. Results The average size of the particles was around 5 nm initially and showed a aggregation upon exposure to the atmosphere for several hours giving average particle size of around 5–20 nm. Batch adsorption studies were performed for the adsorption of fluoride and the results revealed that γ-Fe 2 O 3 nanoparticles posses high efficiency towards adsorption. A rapid adsorption occurred during the initial 15 min by removing about 95 ± 3 % and reached equilibrium thereafter. Fluoride adsorption was found to be dependent on the aqueous phase pH and the uptake was observed to be greater at lower pH. Fourier transform infrared spectroscopy (FT-IR) was used for the identification of functional groups responsible for the adsorption and revealed that the direct interaction between fluoride and the γ-Fe 2 O 3 particles. Conclusions The mechanism for fluoride removal was explained using the dehydoxylation pathway of the hydroxyl groups by the incoming fluoride ion. FT-IR data and other results from the ionic strength dependence strongly indicated that formation of inner-spherically bonded complexes. Molecular clusters were found to be good agreement with experimental observations. These results show direct chemical interaction with fluoride ions.

Denitrifying phosphorus removal was verified in a laboratory anaerobic/anoxic Sequencing Batch Reactor (A/A SBR) for a period of 18 months. The results obtained demonstrated the ability of the anaerobic/anoxic strategy to enrich the growth of denitrifying phosphorus bacteria (DPB) capable of taking up phosphate under anoxic conditions by using nitrate as the electron acceptor. Phosphorus removal efficiency ranging from 40-100% could be attained in an A/A SBR system. Simultaneous anoxic phosphate uptake and biological denitrification under anaerobic/anoxic condition occurred in this system. Batch tests showed, however, that simultaneous presence of carbon and nitrate would be detrimental to denitrifying phosphorus removal. Results of bacteria studies suggested that three denitrifying isolates had aerobic phosphorus removing ability.

Removals of MS2 bacteriophage virus using different membrane materials under different operating pressures were investigated. The results obtained in this study suggested that a better log removal in terms of MS2 bacteriophage virus could be achieved using Polyamide RO membrane under the optimum operating pressure of 100 psi. It is further noted that variable MS2 influent concentration levels resulted in corresponding variable log removals of the bacteriophages by the Polyamide RO membrane. The presence of MS2 bacteriophage virus in the effluent could possibly be due to leakage of bacteriophages through the membranes structure. Investigations using SEM and AFM showed that there were gaps or pores present in the membrane structure which were sufficiently large for the MS2 viruses to pass through.