Biocrude extraction from human-excreta-derived hydrochar for sustainable energy and agricultural applications.

Hydrothermal carbonization may be a sustainable sanitary treatment for wet organic waste including human excreta. Human-excreta-derived hydrochar properties differ from those of typical wet biomass due to the formation of a biocrude-like phase at low reaction temperatures. This study characterized the importance of this phase in terms of hydrochar combustion properties and potential agricultural use. Hydrothermal carbonization of raw human excreta was undertaken at 180, 210, and 240 °C, after which the biocrude phase was extracted with dichloromethane. Physicochemical properties, surface-area parameters, combustion profiles, and gas emissions of non-extracted hydrochar, biocrude, and extracted hydrochar were compared. The potential agricultural use of extracted hydrochar was assessed in germination experiments. Biocrude comprised up to 49.5% of hydrochar mass with a calorific value of >60% that of extracted hydrochar. Biocrude combustion properties were better than those of hydrochar, before and after extraction as demonstrated by higher combustion index value (Si). The extracted hydrochar surface area (34.7 m2 g-1) was greater than that of non-extracted hydrochar (<2 m2 g-1), and seeds germinated more readily due to the lower phytotoxin content. Most macro and micronutrients required for plant growth were retained in the extracted hydrochar. The extraction of biocrude from human-excreta-derived hydrochar not only provided a higher-quality fuel with enhanced combustion properties but also improved hydrochar characteristics, suggesting its potential as a soil additive for enhanced plant growth.

Integrated hydroponics systems with anaerobic supernatant and aquaculture effluent in desert regions: Nutrient recovery and benefit analysis.

Hydroponics is a resource-efficient system that increases food production and enhances the overall sustainability of agricultural systems, particularly in arid zones with prevalent water scarcity and limited areas of arable land. This study investigated zero-waste hydroponics systems fed by agricultural waste streams as nutrient sources under desert conditions. Three pilot-scale systems were tested and compared. The first hydroponics system ("HPAP") received its nutrient source internally from an aquaponic system, including supernatant from the anaerobic digestion of fish sludge. The second system ("HPAD") was sourced by the supernatant of plant waste anaerobic digestion, and the third served as a control that was fed by commercial Hoagland solution ("HPHS"). Fresh weight production was similar in all treatments, ranging from 488 to 539 g per shoot, corresponding to 5.7 to 6.0 kg total wet weight per m2. The recovery of N and P from wastes and their subsequent uptake by plants was highly efficient, with rates of 77 % for N and 65 % for P. Plants that were fed using supernatants demonstrated slightly higher plant quality compared with those grown in Hoagland solution. Over the duration of the full study (3 months), water was only used to compensate for evapotranspiration, corresponding to ~10 L per kg of lettuce. The potential health risk for heavy metals was negligible, as assessed using the health-risk index (HRI < 1) and targeted hazardous quotient (THQ < 1). The results of this study demonstrate that careful management can significantly reduce pollution, increase the recovery of nutrients and water, and improve hydroponics production.

Hydrothermal carbonization reaction severity as an indicator of human-excreta-derived hydrochar properties and it's combustion.

Hydrothermal carbonization (HTC) is an emerging technology that may potentially address sanitation problems and energy scarcity. However, the significance of the parameters that govern HTC (e.g., temperature and time) is not fully understood, in particular for human excreta. A simplified coalification model was used to describe the 'strength' of thermal reactions by combining temperature and time into a single parameter, the severity factor. This study is the first to assess the extent to which a severity coalification model can predict the properties of human-excreta-derived hydrochar for a given severity with different combinations of reaction time and temperature. HTC experiments with raw human excreta were undertaken with 50 mL batch reactors at five different severities. Severity was established with different combinations of temperature (180 °C, 210 °C, and 240 °C) and reaction time based on the severity-factor equation. The resulting hydrochars were tested for combustion properties, and the respective gas emission as well as, physicochemical and surface area parameters. Significant correlations were found between severity and yield (R2 = 0.88), carbon content (R2 = 0.85), and calorific value (R2 = 0.90), with the properties being similar for a given severity but varying with different severities. Hydrochar's contact angle increased from 53.1° to 81.3° with increasing SF, while surface area remained low, ranging from <1 to 5.1 m2g-1, with no definite correlation to SF. Combustion profiles for a given severity were generally similar, but the ignition, peak, and burnout temperatures differed between severities. Gram-Schmidt curves indicated that gas emission profiles are similar for a given severity but vary with different severities. The main gases emitted in combustion were virtually identical in all treatments, and included CO2, alkenes (C9, C10), CH4, and H2O. It is concluded that many properties of hydrochar can be inferred from the severity factor.

Carbon dynamics and energy recovery in a novel near-zero waste aquaponics system with onsite anaerobic treatment.

Aquaponics is gaining renewed interest to enhance food security. This study aimed to investigate the performance of a novel off-grid aquaponics system with near-zero water and waste discharge, focusing on the carbon cycle and energy recovery that was achieved by the addition of onsite anaerobic treatment of the solid waste streams. Following a stabilization stage, the system was closely monitored for four months. Fish tank water was recirculated via solid and nitrification reactors, from which 66% was recycled to the fish tank directly and 34% indirectly through the hydroponically grown plants. Fish solid waste was anaerobically treated, energy was recovered, and the nutrient-rich supernatant was recycled to the plants to enhance production. Plant waste was also digested anaerobically for further recovery of energy and nutrients. Fish stocking density was 15.3 and over time reached approximately 40 kg/m3 where it was maintained. Feed (45% protein content) was applied daily at 2% of body weight. Typical fish performance was observed with a survival rate >97% and feed conversion ratio of 1.33. Lettuce production was up to 5.65 kg/m2, significantly higher than previous reports, largely because of high nutrients reuse efficiency from the anaerobic supernatant that contained 130 and 34 mg/L N and P, respectively. Of the feed carbon, 24.5% was taken up by fish biomass. Fish solid wastes contained 38.2% carbon, of which 91.9% was recovered as biogas (74.5% CH4). Biogas production was 0.84 m3/kg for fish sludge and 0.67 m3/kg for dry plant material. CO2 sequestration was 1.4 higher than the feed carbon, which reduced the system's carbon footprint by 64%. This study is the first to demonstrate highly efficient fish and plant production with near-zero water and waste discharge and with energy recovery that can potentially supply the system's energy demand.

Advanced near-zero waste treatment of food processing wastewater with water, carbon, and nutrient recovery.

A near-zero waste treatment system for food processing wastewater was developed and studied. The wastewater was treated using an anaerobic membrane bioreactor (AnMBR), polished using an outdoor photobioreactor for microalgae cultivation (three species were studied), and excess sludge was treated using hydrothermal carbonization. The study was conducted under arid climate conditions for one year (four seasons). The AnMBR reduced the total organic carbon by 97%, which was mostly recovered as methane (~57%) and hydrochar (~4%). Microalgal biomass productivity in the AnMBR effluent ranged from 0.25 to 0.8 g·L-1·day-1. Nitrogen (N) and phosphorous (P) uptake varied seasonally, from 18 to 45 mg·L-1·day-1 and up to 5 mg·L-1·day-1, respectively. N and P mass balance analysis demonstrated that the process was highly efficient in the recovery of nitrogen (~77%), and phosphorus (~91%). The performance of the microalgal culture changed among seasons because of climatic variation, as a result of variation in the wastewater chemistry, and possibly due to differences among the microalgal species. Effluent standards for irrigation use were met throughout the year and were achieved within two days in summer and 4.5 days in winter. Overall, the study demonstrated a near-zero waste discharge system capable of producing high-quality effluent, achieving nutrient and carbon recovery into microalgae biomass, and energy production as biogas and hydrochar.

Hydrothermal carbonization of anaerobic digestate and manure from a dairy farm on energy recovery and the fate of nutrients.

Hydrothermal carbonization (HTC) of raw and anaerobically digested (AD) manure with either water or whey was studied, with the goal of recovering energy and nutrients. Specifically, the impacts of HTC reaction temperature (180-240 °C), solid feedstock, and type of liquid on hydrochar quality and aqueous phase properties were tested. Of the hydrochars produced, the calorific value of whey-based hydrochar was the highest, (19.4 and 16.0 MJ/kg for manure and digestate, respectively). Overall, the net energy gain was higher for HTC of manure with whey (7.4-8.3 MJ/kg dry feedstock) and water (4.4-5.1 MJ/kg) compared to the combined AD-HTC process with whey (4.4-5.3 MJ/kg) and water (2.3-2.9 MJ/kg). Digestate-derived hydrochar contained up to 1.8% P, higher than manure-derived hydrochar (≤1.5%). Using whey as a liquid for HTC increased the aqueous-phase N-P-K concentrations up to 3,200, 410, and 7,900 mg/L, respectively, suggesting its potential use as a liquid fertilizer.

Facile activation of sludge-based hydrochar by Fenton oxidation for ammonium adsorption in aqueous media.

Lately, there has been a growing interest in converting low-cost biomass residuals, including wastewater sludge, into char-like materials for various applications. In this research, ammonium (NH4+) adsorption and desorption potential of hydrochar activated via Fenton oxidation were systematically investigated. Hydrochar was prepared from domestic wastewater treatment plant sludge and activated by Fenton oxidation using different H2O2 concentrations, H2O2/Fe2+ ratios, and activation times. The activated hydrochars (AHs) were characterized by ATR-FTIR, high-resolution XPS, BET specific surface area, and SEM, and their NH4+ adsorption capacity was analyzed. The NH4+ adsorption isotherms and kinetics, adsorption in the presence of competing ions (with and without humic acid), and NH4+ desorption were investigated. The results show that following hydrochar activation, the acidic groups' concentration and the BET surface area increased, but the morphology remained essentially unchanged. It was also found that the activation occurs within a few minutes when using a relatively low concentration of reagents, and without extensive post-treatment steps. The NH4+ adsorption onto AH at equilibrium fitted the Langmuir isotherm model, with a maximum adsorption capacity of 30.77 mg g-1, and the NH4+ adsorption kinetics fitted the pseudo-second-order model. NH4+ adsorption in the presence of competing ions decreased by up to 33 ± 3%. NH4+ desorption experiments demonstrated that NH4+ recovery can reach 33 ± 5% with ultrapure water and 67 ± 2% with 2 M KCl. The results of this study indicate that Fenton oxidation is a promising alternative for hydrochar activation, and can be used as an adsorbent for NH4+ remediation in wastewater treatment processes.

Poultry litter hydrochar as an amendment for sandy soils.

The conversion of poultry litter to hydrochar has been proposed for stabilization of the soils and to eliminate pathogens. Still, research on the hydrochar's effect on soil properties as a function of production temperature, and its direct use with plants is limited in general and even less so on poultry litter. We characterized poultry litter hydrochar as an amendment for sandy soils in terms of changes to the soil's bulk density, porosity, water-retention capacity, and fertility. Soil bulk density, porosity and water-retention capacity were determined in a pneumatic tension plate system for sand with hydrochar-amendment rates of 0.5, 1 and 2%, and hydrochar-production temperature of 180, 220, and 250 °C. Soil fertility was assessed by growing lettuce seedlings in a randomized block design planter experiment, consisting of 16 blocks that were sampled every 10 days. The addition of poultry litter hydrochar resulted in decreased soil bulk density. Soil porosity increased with hydrochar generated at a temperature of up to 220 °C, and decreased with hydrochar generated at 250 °C. Soil water content increased as compared to unamended sand, but decreased with increasing hydrochar-production temperature, probably due to increasing hydrophobicity of the poultry litter hydrochar. The addition of hydrochar at concentrations of 0.5 and 1% resulted in improved plant growth despite an initial delay. While increased soil moisture due to increased soil water-retention capacity was confirmed, it did not seem to be responsible for the improved plant growth. It was also demonstrated for the first time that hydrochar decreases nitrate leaching from soils. Therefore, poultry litter-derived hydrochar seems to be an adequate amendment for sandy soils.

Phosphorous recovery from a novel recirculating aquaculture system followed by its sustainable reuse as a fertilizer.

Phosphorus (P) is an essential element for life that is introduced through feed in modern aquaculture-the fastest growing food production sector. P can also be a source of environmental contamination and eutrophication if mistreated. Fish assimilate only 20-40% of the applied P; the rest is released into the water. The goals of this research were to study the fate of P in a novel intensive near-zero discharge (<1%) recirculating aquaculture system (RAS). We also tested means to recover and reuse the removed P. Water, sludge and the microbial communities in the different treatment units of the system were analyzed. The treated sludge was tested as a potential substitute for P fertilization in a planter experiment. Of the applied P, 29.5% was recovered by fish, 69.8% was found in the fish sludge and 3.8% was released into the water as soluble reactive P. The P concentration in the fish tank remained stable, likely due to its uptake by denitrifying polyphosphate-accumulating organisms and its precipitation in the RAS's anaerobic reactor. Thus, only 1.5% of the applied P was discharged as effluent, and 69% recovered. The dominant minerals were from the apatite group, followed by the struvite family. Differences in mineral abundance between thermodynamic prediction and actual findings were most probably due to biomineralization by bacteria. Similar plant biomass was recorded for the commercial and digested-sludge fertilization treatments. Biological P removal and recovery from RAS was successfully studied and demonstrated.

Glutamate dehydrogenase deficiency disrupts glutamate homeostasis in hippocampus and prefrontal cortex and impairs recognition memory.

Glutamate Dehydrogenase 1 (GDH), encoded by the Glud1 gene in rodents, is a mitochondrial enzyme critical for maintaining glutamate homeostasis at the tripartite synapse. Our previous studies indicate that the hippocampus may be particularly vulnerable to GDH deficiency in central nervous system (CNS). Here, we first asked whether mice with a homozygous deletion of Glud1 in CNS (CNS-Glud1 -/- mice) express different levels of glutamate in hippocampus, and found elevated glutamate as well as glutamine in dorsal and ventral hippocampus, and increased glutamine in medial prefrontal cortex (mPFC). l-serine and d-serine, which contribute to glutamate homeostasis and NMDA receptor function, are increased in ventral but not dorsal hippocampus, and in mPFC. Protein expression levels of the GABA synthesis enzyme glutamate decarboxylase (GAD) GAD67 were decreased in the ventral hippocampus as well. Behavioral analysis revealed deficits in visual, spatial and social novelty recognition abilities, which require intact hippocampal-prefrontal cortex circuitry. Finally, hippocampus-dependent contextual fear retrieval was deficient in CNS-Glud1 -/- mice, and c-Fos expression (indicative of neuronal activation) in the CA1 pyramidal layer was reduced immediately following this task. These data point to hippocampal subregion-dependent disruption in glutamate homeostasis and excitatory/inhibitory balance, and to behavioral deficits that support a decline in hippocampal-prefrontal cortex connectivity. Together with our previous data, these findings also point to different patterns of basal and activity-induced hippocampal abnormalities in these mice. In sum, GDH contributes to healthy hippocampal and PFC function; disturbed GDH function is relevant to several psychiatric and neurological disorders.

Potential environmental impact resulting from biased fish sampling in intensive aquaculture operations.

Aquaculture contributes to global food security, producing over 70 million tons of fish and aquatic products annually. Protein rich fish feeds, together with labor costs are the most expensive component costs in aquaculture. Feed application is given as percent of fish weight and therefore, reliable biomass assessment is essential for profitable and environmentally sound aquaculture. Fish biomass estimates are typically based on sampling <2% of the fish population. The goals of this research were to estimate potential biases associated with fish sampling in recirculating aquaculture systems (RAS), and the potential economic and environmental implications of such biased estimations. The size of the biased sampling-based estimates of fish biomass in two cultured species was shown to be larger than what the confidence interval suggests, even after >20% of the population was sampled. Such biases, if indeed common, will most likely result in over/underfeeding, both entailing negative economic and environmental consequences. We advocate conducting similar studies with major cultured fish to generate "bias correction tables" for adjusting fish feeding rate to bias-corrected biomass. These will help reduce the potential economic losses and negative environmental impacts of aquaculture practice.

Nutrient Behavior in Hydrothermal Carbonization Aqueous Phase Following Recirculation and Reuse.

Hydrothermal carbonization (HTC) has received much attention in recent years as a process to convert wet organic waste into carbon-rich hydrochar. The process also generates an aqueous phase that is still largely considered a burden. The success of HTC is dependent on finding solutions for the aqueous phase. In the present study, we provide the first investigation of recirculation of the aqueous phase from HTC of poultry litter as a means to concentrate nutrients and its subsequent application to agriculture as a fertilizer. Aqueous-phase recirculation generally resulted in an increase in nitrogen, phosphorus, and potassium concentrations up to cycle 3 with maximum concentrations reaching up to 5400, 397, and 23300 mg L-1 for N, P, and K, respectively. Recirculation did not adversely affect hydrochar composition or calorific value. The recirculated and nonrecirculated aqueous phases were able to support lettuce growth similar to a commercial fertilizer. Results from this study indicate that the combination of aqueous-phase recirculation and use as a fertilizer could be a suitable method to reutilize the aqueous phase and recycle nutrients back into agriculture, thus increasing HTC efficiency and economic feasibility.

Characterization and utilization of hydrothermal carbonization aqueous phase as nutrient source for microalgal growth.

This study investigated the feasibility of using hydrothermal carbonization (HTC) aqueous phase as an alternative nutrient source for microalgae cultivation, and the microalgae cultivation capability to treat this complex medium to a level enabling its reuse or discharge. HTC of activated sludge was optimized in terms of the energy content of the solid hydrochar and the nutrient content of the HTC aqueous phase adequate for microalgal growth. Growth rates of Coelastrella sp. and Chlorella sp. in the HTC aqueous phase based growth medium and a control medium (mBG11) were similar, indicating that the HTC aqueous phase does not inhibit the microalgae growth. Nitrogen and phosphorus concentrations were reduced by >90% and dissolved organic carbon by 80% after 6 days of cultivation, resulting in water quality suitable for reuse or discharge. This study confirms the microalgae high potential in a circular bio-economy to valorize wet bio-waste streams from various treatment methods.

Real-time analysis of atrazine biodegradation and sessile bacterial growth: A quartz crystal microbalance with dissipation monitoring study.

Biodegradation is a fundamental process for removal of the environmentally prevalent herbicide, atrazine, from contaminated waters. Biodegradation is more efficient when bacteria are attached on surface of an adsorbing carrier that supports the microbial population. However, for various reasons, biodegradation is almost always monitored in the liquid phase. In this study, we employ a novel Quartz Crystal Microbalance with Dissipation technique (QCM-D) for continuous, real-time monitoring of the attachment of atrazine-degrading bacteria to the surface, atrazine adsorption and degradation, and the consequent proliferation of the irreversibly attached sessile bacteria. The effect of atrazine biodegradation was observed in a batch mode of operation, in which a significant frequency decrease of the piezoelectric sensor was observed in the QCM-D, due to the proliferation of atrazine-degrading bacteria on the expense of atrazine. The latter was confirmed microscopically. Results also suggest that the viscoelastic properties of the atrazine-degrading consortium immediately changed in response to the presence of atrazine, whereas those of the non-degrading consortium were not affected. Importantly though, atrazine adsorption was similar regardless of the sessile consortia layers. When the QCM-D flow cell was exposed to a continuous flow of saturated atrazine solution, the degrading consortium layer was significantly more fluidic compared to batch mode conditions. The magnitude and kinetics of atrazine adsorption, which were monitored using QCM-D, were higher on bacterial cells comparing to the pristine, polystyrene-coated sensor. Findings from the current study can improve bioremediation design and open an avenue for studies on biodegradation and adsorption of micro-pollutants using QCM-D technology.

Antibiotic-Resistant Bacteria in Greywater and Greywater-Irrigated Soils.

This study represents the first systematic attempt to evaluate antibiotic-resistant bacteria (ARB) occurrence in treated greywater and the potential spread of these bacteria from the greywater to greywater-irrigated soil. Treated greywater from three recirculating vertical flow constructed wetlands, each located in a household in the central Negev Desert, Israel, was surveyed. The presence of antibiotic-resistant bacteria in raw and treated greywater was investigated with culture and molecular methods, as well as their presence in the corresponding treated-greywater-irrigated soils. Additionally, the effectiveness of chlorination to prevent the spread of ARB was tested. The total count of tetracycline-resistant bacteria significantly increased in the treated greywater, likely due to their concentration on the filter matrix of the treatment systems. Twenty-four strains of tetracycline-resistant bacteria were isolated and identified at the genus level by 16Sr RNA gene sequencing. All the tetracycline-resistant bacteria showed high resistance traits, and some of them presented multiple antibiotic resistances. Six tetracycline resistance genes (coding for efflux and ribosomal resistance mechanisms) and five ß-lactamase genes were detected. In 14 of the isolated strains, the gene tet39, which is phylogenetically related to both environmental and clinical strains, was identified. All the tet39 resistant bacteria were positive to at least one of the ß-lactamase genes tested. Chlorination was found to be an efficient method to reduce ARB in treated greywater. We concluded that disinfection of treated greywater may reduce the risks not only from the potential presence of pathogens but also from the presence of ARB and antibiotic resistance genes.

Wetting properties of poultry litter and derived hydrochar.

Detailed assessment of hydrochar wetting properties, which could provide an essential understanding of underlying mechanisms during its application to soils, is lacking. We characterized hydrochar produced from hydrothermal carbonization (HTC) performed on poultry litter at various temperatures and for different times in terms of hydrophobicity and surface free energy properties. Hydrochar was more hydrophobic than untreated poultry litter, and its hydrophobicity increased with increasing HTC temperature (contact angle > 130°). These changes were correlated with degradation of hemicellulose and cellulose. Hydrochar produced at 250°C contained mostly lignin and displayed high hydrophobicity over both prolonged wetting periods and repeated wetting cycles. Surface free energy was calculated using the Owens-Wendt-Rabel-Kaelble and Wu models, with the latter resulting in lower standard errors. The surface free energy decreased as HTC treatment severity increased from 26 mJ/m2 in the poultry litter to 8 mJ/m2 after treatment at 250°C for 60 min. The dispersive component fraction of the surface free energy increased with increasing treatment severity. This study demonstrated that changes in the physical composition of hydrochar due to increased treatment severity increase its hydrophobicity and decrease its surface free energy. Moreover, due to non-persistent hydrophobicity, hydrochar produced at temperatures lower than 250°C will likely not show adverse effects on soils.

Nitrous oxide emissions from near-zero water exchange brackish recirculating aquaculture systems.

The development of intensive recirculating aquaculture systems (RAS) with low water exchange has accelerated in recent years as a result of environmental, economic and other concerns. In these systems, fish are commonly grown at high density, 50 to 150kg/m3, using high-protein (30%-60%) feeds. Typically, the RAS consists of a solid treatment and a nitrification unit; in more advanced RAS, there is an additional denitrification step. Nitrous oxide (N2O), a byproduct during nitrification and denitrification processes, is a potent greenhouse gas that destroys the ozone layer. The aim of this study was to measure and assess N2O emissions from a near-zero discharge land-based saline RAS. N2O flux was monitored from the RAS's fish tank, and moving-bed nitrification and activated-sludge (with intrinsic C source) denitrification reactors. N2O emission potential was also analyzed in the laboratory. N2O flux from the denitrification reactors ranged between 6.5 and 48mg/day, equivalent to 1.27±1.01% of the removed nitrate-N. Direct analysis from the fish tank and nitrification reactors could not be performed due to high aeration, which diluted the N2O concentration to below detection limits. Thus, its potential emission was estimated in the laboratory: from the fishponds, it was negligible; from the nitrification reactor, it ranged between 0.4 and 2.8% of the total ammonia-N oxidized. The potential N2O emission from the denitrification reactor was 3.72±2.75% of the reduced nitrate-N, within the range found in the direct measurement. Overall, N2O emission during N transformation in a RAS was evaluated to be 885mg/kg feed or 1.36g/kg fish production, accounting for 1.23% of total N application. Consequently, it is estimated that N2O emission from aquaculture currently accounts for 2.4% of the total agricultural N2O emission, but will decrease to 1.7% by 2030.

The effect of water contamination and host-related factors on ectoparasite load in an insectivorous bat.

We examined the effects of sex, age, and reproductive state of the insectivorous bat Pipistrellus kuhlii on the abundance and prevalence of arthropod ectoparasites (Macronyssidae and Cimicidae) in habitats with either sewage-polluted or natural bodies of water, in the Negev Desert, Israel. We chose water pollution as an environmental factor because of the importance of water availability in desert environments, particularly for P. kuhlii, which needs to drink on a daily basis. We predicted that parasite infestation rates would be affected by both environment and demographic cohort of the host. We found that female bats in the polluted site harbored significantly more mites than female bats in the natural site and that juveniles in the polluted site harbored significantly more cimicid individuals than juveniles in the natural site. We further found that age and sex (host-related factors) affected ectoparasite prevalence and intensity (i.e., the abundance of parasites) in the polluted site. Our results may suggest that the interaction between host-related and environment-related factors affected parasite infestations, with females and young bats being more susceptible to ectoparasites when foraging over polluted water. This effect may be particularly important for bats that must drink or forage above water for other wildlife that depend on drinking water for survival.

Greywater-induced soil hydrophobicity.

Greywater (GW) reuse for irrigation is a common method of reducing domestic consumption of fresh water. Most of the scientific research and legislation efforts have focused on GW's health risks, while less attention has been given to its environmental outcomes. One of the environmental risks of GW irrigation is its possible effect on soil hydraulic properties. This research examined the ability of GW to induce soil hydrophobicity, as well as its degree and persistence. Fresh water (control) and three model GW solutions representing raw, treated and highly treated GW were used to wet fine-grained sand. Every treatment was subjected to five cycles of wetting, incubation (at 5 °C or 30 °C) and drying (60 °C). After each cycle, capillary rise was measured and the contact angle (CA) was calculated. Samples were also tested by the Wilhelmy plate method to retrieve advancing and receding CA and reservoir surface tension. Water repellence of the sand, as implied from the CA, increased with increasing GW concentration and was highest in the sand coated with the model raw GW and incubated at 5 °C. However, none of the treatments resulted in what is considered to be "water-repellent soil". Furthermore, when raw GW-coated sand was immersed in water, its surface tension was significantly reduced relative to the other treatments, implying a release of surface-active compounds from the sand into the water. It was postulated that untreated GW may induce sub-critical water repellence in sand. However, this effect is sensitive to biodegradation and washing processes and is therefore temporary.

[UTILIZATION OF WHOLE EXOME SEQUENCING IN DIAGNOSTICS OF GENETIC DISEASE: RABIN MEDICAL CENTER'S EXPERIENCE].

INTRODUCTION: Whole exome sequencing is a diagnostic approach for the identification of molecular etiology in patients with suspected monogenic diseases. In this article we report on our experience with whole-exome sequencing (WES) of DNA samples taken from patients referred for genetic evaluation due to suspected undiagnosed genetic conditions. METHODS: Exome enrichment was achieved by Nextera Rapid Capture Expanded Exome Kit. Whole-exome sequencing was performed on Illumina HiSeq 2500. Potentially damaging rare variants were selected for familial cosegregation analysis. RESULTS: A total of 39 patients presenting a wide range of phenotypes suspected to have a genetic cause were sent to WES. Approximately 80% were children with neurological phenotypes. Variations having a high probability of being causative were identified in 20 families, achieving a 51.3% molecular diagnostic rate. Among these, 7 exhibited autosomal dominant disease, 12 autosomal recessive diseases and one X-linked disease; 28% of the patients (11/39) were found to carry a novel mutation located in previously reported genes. Novel mutations located in genes not known to be associated with genetic disease were identified in 23% of the patients (9/39). CONCLUSIONS: Whole exome sequencing identified the underlying genetic cause in more than half of the patients referred for evaluation in the genetics clinic at the tertiary hospital. These data demonstrate the utility of WES as a powerful tool for effective diagnostics of monogenic genetic diseases.