Sensors for Biomass Monitoring in Vegetated Green Infrastructure: A Review.

Bioretention cells, or rain gardens, can effectively reduce many contaminants in polluted stormwater through phytoremediation and bioremediation. The vegetated soil structure develops bacterial communities both within the soil and around the vegetation roots that play a significant role in the bioremediative process. Prediction of a bioretention cell's performance and efficacy is essential to the design process, operation, and maintenance throughout the design life of the cell. One of the key hurdles to these important issues and, therefore, to appropriate designs, is the lack of effective and inexpensive devices for monitoring and quantitatively assessing this bioremediative process in the field. This research reviews the available technologies for biomass monitoring and assesses their potential for quantifying bioremediative processes in rain gardens. The methods are discussed based on accuracy and calibration requirements, potential for use in situ, in real-time, and for characterizing biofilm formation in media that undergoes large fluctuations in nutrient supply. The methods discussed are microscopical, piezoelectric, fiber-optic, thermometric, and electrochemical. Microscopical methods are precluded from field use but would be essential to the calibration and verification of any field-based sensor. Piezoelectric, fiber-optic, thermometric, and some of the electrochemical-based methods reviewed come with limitations by way of support mechanisms or insufficient detection limits. The impedance-based electrochemical method shows the most promise for applications in rain gardens, and it is supported by microscopical methods for calibration and validation.

Impact of Landfill Gas Exposure on Vegetation in Engineered Landfill Biocover Systems Implemented to Minimize Fugitive Methane Emissions from Landfills.

Engineered landfill biocovers (LBCs) minimize the escape of methane into the atmosphere through biological oxidation. Vegetation plays a crucial role in LBCs and can suffer from hypoxia caused by the displacement of root-zone oxygen due to landfill gas and competition for oxygen with methanotrophic bacteria. To investigate the impact of methane gas on vegetation growth, we conducted an outdoor experiment using eight vegetated flow-through columns filled with a 45 cm mixture of 70% topsoil and 30% compost, planted with three types of vegetation: native grass blend, Japanese millet, and alfalfa. The experiment included three control columns and five columns exposed to methane, as loading rates gradually increased from 75 to 845 gCH4/m2/d over a period of 65 days. At the highest flux, we observed a reduction of 51%, 31%, and 19% in plant height, and 35%, 25%, and 17% in root length in native grass, Japanese millet, and alfalfa, respectively. The column gas profiles indicated that oxygen concentrations were below the levels required for healthy plant growth, which explains the stunted growth observed in the plants used in this experiment. Overall, the experimental results demonstrate that methane gas has a significant impact on the growth of vegetation used in LBCs.

Effectiveness of a Two-Tier Family-Oriented Intervention in Enhancing the Family Functioning and Care Capacity of the Family Caregivers of Stroke Survivors: Protocol for a Randomized Controlled Trial.

BACKGROUND: Stroke has profound impacts on families. Often, family members, including stroke survivors and the person who takes up the role of the primary caregiver, would encounter demands on finances, rehabilitation arrangement, and even conflicts. Hence, a family-oriented intervention is expected to enable families to rebuild internal and external resources to achieve optimal rehabilitation and community reintegration. OBJECTIVE: This study aims to describe a design of a two-tier family-oriented care management intervention for enhancing the family functioning and care capacity of the caregivers of stroke survivors. METHODS: The two-tier care management intervention was guided by a standardized protocol conducted by trained professional care managers (first tier) with the support of trained volunteers (second tier), which lasted for 8-12 weeks. Participants were recruited through collaborating hospitals according to inclusion and exclusion criteria. In order to examine the effectiveness and cost-effectiveness of the two-tier care management intervention, a two-arm randomization multicenter study was designed, including an active comparison group, which was guided by a standardized protocol conducted by trained volunteers. Dyadic participants, including both stroke survivors and their primary caregivers for both groups, were invited to participate in a questionnaire survey using standardized and purposefully developed measures 3 times: before the intervention, immediately after the intervention, and 2 months after the intervention. The primary outcome was family functioning measured by the Family Role Performance Scale and Family Assessment Device-General Functioning Scale. The secondary outcomes included caregiving burden, depressive symptoms, care management strategies, and the incremental cost-effectiveness ratio. RESULTS: Recruitment began in January 2017 and was completed at the end of April 2019. Data collection was completed at the end of March 2020. As of March 2020, enrollment has been completed (n=264 stroke caregivers). A total of 200 participants completed the baseline questionnaires. We aim to publish the results by mid-2021. CONCLUSIONS: This study successfully developed a two-tier care management protocol that aims to enhance the family functioning of the caregivers of stroke survivors. Guided by a standardized protocol, this family-oriented two-tier intervention protocol was found to be feasible among Chinese families. TRIAL REGISTRATION: ClinicalTrials.gov NCT03034330; https://ichgcp.net/clinical-trials-registry/NCT03034330. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/16703.

Nutrient leaching behavior of green roofs: Laboratory and field investigations.

Despite the benefits of green roofs in managing stormwater quality, green roofs especially at their early age might leach nutrients. Research in this regard is still very limited. Therefore, this paper conducted both the laboratory and field observations to characterize and model the leaching of nutrients including nitrogen (N) and phosphorus (P) and to examine the discrepancy in knowledge produced from these two settings. The experiment revealed that the higher the initial nutrient contents of media were, the higher the degree of nutrient leaching was. The nutrient leaching from both the laboratory cells and the field green roof declined temporally, which was largely explained by the cumulative inflow. The semi-physically based nutrient leaching model generally captured the nutrient leaching from both the laboratory cells (R2 in the range of 0.87-0.98) and the field green roof (R2 in the range of 0.28-0.86). The mass balance analysis for the laboratory cells demonstrated that the masses of nutrients leached in outflow were 85-112% of the nutrients reduced in media in general (except P of two laboratory cells). The analysis and modeling results supported that media was the primary source for nutrients leached and the pattern of nutrient leaching was consistent with wash-off being the dominant process. The results also revealed the difference in the P leaching between the laboratory cells and the field green roof. Apart from the wash-off, other chemical and biological processes and/or nutrient sources might play non-negligible roles on the P leaching of the field green roof, implied by the relatively low performance of the models (R2 of approximately 0.30 in both the regression analysis and the nutrient leaching model). The difference observed between the laboratory experiment and the field observation also calls into attention when translating knowledge derived from laboratory experiments into real practice.

Characterization of domestic wastewater released from 'green' households and field study of the performance of onsite septic tanks retrofitted into aerobic bioreactors in cold climate.

This study aimed to investigate the efficacy of private septic systems retrofitted into aerobic bioreactors with 'SludgeHammer' technology. In addition, the study attempted to characterize the strength of domestic wastewater released from 'green' households practicing water conservation strategies. Ten retrofitted onsite septic systems were studied in the Edmonton area, Alberta (AB) Canada during winter. These systems could remove BOD5 and TSS by 92 ± 5 and 92 ± 6% respectively which, according to Albertan regulatory standards, were characteristic removal efficiencies of the secondary treatment in the subsequent drain field. These removal efficiencies were remarkable given the strength of the influent wastewater. The raw wastewater carried significantly high pollutant concentrations (1160 ± 350 mg BOD5/L, 1653 ± 1174 mg TSS/L, 99 ± 19 mg NH4+-N/L, 100 ± 56 mg TN/L, and 39 ± 28 mg PO43--P/L), characterizing it as high-strength domestic wastewater. Mixing provided by the aerator could only suspend 1/34th (3% m/m) of the solids in the bioreactor and consequently released significantly low solid concentrations (195 ± 206 mg TSS/L) into the final treatment component. As such, this technology did not impair the natural function of septic tanks or did not create any unintended excessive solid loading on drain field as a consequence of the added mixing energies provided by the active aeration. Nitrogen balance suggested the possibility of simultaneous nitrification and denitrification (SND) in the aerobic bioreactors. In some cases, PO43--P removal efficiency was as high as that in enhanced biological phosphate removal (EBPR) process (81-97%). Phosphorus balance estimated that non-assimilative pathways (i.e., EBPR + biologically induced phosphate precipitation (BIPP)) contributed 50-99% to overall phosphorus removal in the system. Long HRTs, high influent BOD5 and anaerobic/aerobic zoning in the bioreactor most likely provided favorable conditions for SND and high phosphorus removal efficiencies in the retrofitted onsite wastewater treatment systems (OWTS).

A Velocity Meter for Quantifying Advection Velocity Vectors in Large Water Bodies.

A velocity meter was designed and built in order to meet market needs for an affordable instrument that measures the range of velocity magnitudes and direction experienced in medium- to large-sized water bodies. The velocity meter consists of a graduated plate with an injector protruding from the center and a camera held downward above the plate. Once the Dye Injection Velocity (DIV) meter is in the flow, dye is injected and the camera records the dye fluid transport. The recorded video is analyzed to determine the local flow velocity and direction. The DIV was calibrated for a range of velocities between 0.0094 m/s and 0.1566 m/s using particle image velocimetry (PIV) in a flow visualization flume. The accuracy of the instrument was found to be +6.3% and -9.8% of full scale. The coefficient of determination of the calibration curve was equal to 98%. Once calibrated, the DIV was deployed to the Inverness Stormwater pond in Calgary, Canada, for validation tests against an Acoustic Doppler Velocity (ADV) meter. During the validation tests, both flow velocity magnitude and direction were measured at several spatial points. The velocity magnitude results showed good agreement and the Mann-Whitney test showed no statistically significant difference (p-value > 0.05). At two spatial points, the differences between direction data were significant, which could be caused by the random errors involved in the validation test. However, the averaged data showed good agreement.

Acupuncture for Poststroke Dysphagia: A Pilot, Nonrandomized, Self-Controlled Trial.

OBJECTIVE: To evaluate the effectiveness and safety of acupuncture treatment for dysphagia as a complication of stroke. Methods and Design. This is a multicenter, pragmatic, nonrandomized, self-controlled clinical trial. A total of 39 patients were recruited from several Chinese medicine outpatient clinics and hospital-affiliated speech therapy outpatient clinics in Hong Kong. 26 patients completed all the 24 sessions of acupuncture treatment within two months, and only 12 of them were used as self-control. For the self-control group, the retrospective clinical data was taken from the electronic patient records with patient consent. The descriptive swallowing function data were converted into the quantitative Royal Brisbane Hospital Outcome Measure for Swallowing (RBHOMS) scores by two registered speech therapists through a validation process. And the data were validated by reaching consensus between the two speech therapists. All subjects underwent a baseline assessment before commencement of treatment, and outcome assessments were conducted upon the completion of treatment. The primary outcome measure is the RBHOMS score, which is a swallowing disability rating scale for monitoring difficulties in daily swallowing function. Secondary outcome measures include the Chinese version of the Swallow Quality-of-Life Questionnaire and adverse events. All the primary and secondary outcomes were assessed at baseline as well as at the end of acupuncture treatment (month 2). RESULTS: A total of 39 participants aged 46 to 89 years were enrolled in the study, and the male-to-female ratio was 15 : 11. The mean baseline RBHOMS score of all 39 participants was 5.92 ± 2.23. The mean retrospective RBHOMS score of the 12 subjects who were used as self-control was 5.67 ± 1.72 before enrollment, while the mean RBHOMS score of the 26 participants who completed all the 24 sessions of treatment was 6.92 ± 2.07. There were statistically significant differences between the RBHOMS score at the completion of treatment and baseline (p=0.006), and retrospective data (p=0.042). Moreover, a significant difference was also found in terms of swallow quality-of-life score before and after acupuncture treatment (p < 0.01). CONCLUSIONS: This pilot study provides preliminary evidence for the effectiveness of acupuncture for poststroke dysphagia. The findings from this trial can be used as a foundation for future full-scale randomized controlled clinical trials to assess the efficacy and safety of acupuncture for poststroke dysphagia. Ethics and Dissemination. The ethical approval of the clinical research study was granted by the Research Ethics Committee of both New Territories East and West Cluster of Hong Kong. Written informed consent was obtained from all participants, and the study was undertaken according to the ICH-GCP Guidelines. Trial Registration. This trial is registered with ChiCTR-TRC-12002621 and the registration date is 2012-10-26.

Augmentation of Biogranules for Enhanced Performance of Full-Scale Lagoon-Based Municipal Wastewater Treatment Plants.

This study investigated the treatment performance of lagoon-based municipal wastewater treatment plants (LWWTPs) inoculated by proprietary biogranules. Augmentation process included enhancing the microbial community of lagoon basins by weekly addition of biogranules over the treatment seasons (summer and fall). Effluent qualities before and after the augmentation process were compared, and the results were reported as "enhanced treatment efficiencies, EE". Very low concentrations of 5-day biochemical oxygen demand (BOD5), total nitrogen (TN), total Kjeldahl nitrogen (TKN), ammonium nitrogen (N-NH4), and total phosphorus (TP) were detected at discharge points after the augmentation process, which corresponded to enhanced treatment efficiencies of 86, 74, 72, 92.7, and 71%, respectively. Significant reduction in total coliform and E. coli concentrations in the effluents (91 and 98%, respectively) demonstrated the capability of granule-based lagoons in destroying pathogens. Adding biogranules to lagoons was an efficient remedy for excess sludge buildup in short and long runs. Hence, inoculating lagoon plants using biogranules was suggested as an effective technique to augment rural wastewater treatment facilities.

The impact of media, plants and their interactions on bioretention performance: A review.

Bioretention systems have gained considerable popularity as a more natural approach to stormwater management in urban environments. The choice of bioretention media is frequently cited as one of the critical design parameters with the ultimate impact on the performance of the system. The goal of this review is to highlight data that challenge the importance of media as being the dominant design parameter and argue that the long-term performance is shaped by the interactions between media and the living components of a bioretention system, especially vegetation. Some of the key interactions are related to the impact of plant roots on media pore structure, which has implications on infiltration, storage capacity, and treatment. Another relevant interaction pertains to evapotranspiration and the associated impacts on the water balance and the water quality performance of bioretention systems. The impacts of vegetation on the media are highlighted and actual, as well as potential, impacts of plant-media interactions on bioretention performance are presented.

Pilot-scale investigation on nutrient removal characteristics of mineral-rich aerobic granular sludge: Identification of uncommon mechanisms.

This study investigated nutrient removal characteristics and the related pathways in aerobic granular reactors using three pilot-scale granular sequencing batch reactors (GSBRs) treating wastewaters of diverse carbon and nutrient strength. The GSBRs were operated with alternating (AN/O/AX/O_SBR and AN/O_SBR) and purely-aerobic (O_SBR) operation modes. Mineral-rich aerobic granules with hydroxyapatite (HAp) core were cultivated in all the three GSBRs. The highest nitrogen removal efficiency (75%) was achieved in AN/O/AX/O_SBR and O_SBR and the lowest (22%) in AN/O_SBR, establishing a quasi-linear relationship with organic loading rate (OLR). Phosphorus removal efficiencies of 55-63% were achieved in the GSBRs despite different influent PO4-P concentrations. Heterotrophic nitrification and biologically-induced phosphate precipitation (BIPP) became the dominant nutrient depletion pathways, contributing 61-84% and 39-96% to overall ammonium nitrogen and phosphorus removal, respectively. A direct relation was noted between heterotrophic nitrification efficiency (ηHeterotrophic nitrification) and nutrient availability, as nitrification efficiencies of 18 and 64% were observed for COD:Ninf of 5 and 20, respectively. Whereas, BIPP efficiency (ηBIPP) established inverse relation with (COD:P)inf and (Ca:P)inf and direct relation with phosphorus concentration beyond microbial growth requirement. Core heterotrophic nitrifiers and bio-calcifying species were identified as {Thauera and Flavobacterium} and {Flavobacterium, Acinetobacter, Pseudomonas, and Corynebacterium}, respectively. Ca-P crystallization was proposed to be via phosphate precipitation on calcite surfaces. Granulation mechanism was proposed as crystallization on bio-aggregates' periphery and then crystal growth toward the core.

Response of green roof performance to multiple hydrologic and design variables: a laboratory investigation.

Multiple factors affect green roof performance and their effects might vary at different stages of operation. This paper aimed to link green roof performance to hydrologic variables (antecedent moisture condition (AMC) and rainfall intensity) and design variables (growing medium (GM) type and depth) under multiple dimensions at the early stage of operation using laboratory experiment data. The results showed that the AMC is the most influential factor of hydrologic performance, whereas the GM type appeared to primarily affect the nutrient levels of the outflow. The significant main effects of other variables and interaction effects between two variables point to challenges in green roof design.

Pharmacist Clinical Interventions and Discharge Counseling in Medical Rehabilitation Wards in a Local Hospital: A Prospective Trial.

Patients undergoing rehabilitation experience numerous changes in medication regimens during care transitions, exposing these patients to an increased risk of drug-related problems (DRPs). A prospective, non-randomized, quasi-experimental study was conducted in medical rehabilitation wards to evaluate the impact of pharmacist-delivered interventions and counseling on 30-day unplanned health care utilization and medication adherence for selected rehabilitation patients. A pharmacist provided medication reconciliation and counseling before discharge. Phone follow-up was completed 30 days after discharge to assess for unplanned health care utilization rate and medication adherence. A total of 85 patients (n = 43 in prospective intervention group and n = 42 in historical usual care group) were included. Among the intervention group, 23 DRPs were identified in 14 (32.6%) patients, resulting in 51 interventions. The intervention group had a significantly lower unplanned health care utilization rate than the usual care group (25.6% vs. 47.6%, p = 0.035). The risk of unplanned health care utilization was reduced by over 60% (Odds ratio (OR) = 0.378; 95% CI = 0.15-0.94). Patients reporting medium to high medication adherence increased from 23.6% to 88.4% 30 days after counseling (p < 0.05). Pharmacist medication reconciliation and discharge counseling reduced unplanned health care utilization 30 days after discharge and improved medication adherence.

Finding Knowledge Gaps in Aerobic Granulation Technology.

This review identifies the knowledge gaps in aerobic granulation technology and defines some problems for future studies. In particular, extracellular polymeric substances (EPSs) should be further characterized to understand the intermolecular interactions among these polymers, the role of chelating agents in destabilizing EPS ionic bridges needs further elucidation, and early detection of the quorum-quenching enzymes should be considered to avoid granule segregation and process failure. Furthermore, the process should be supplemented with volatile fatty acids as electron donors/carbon sources, and appropriate anoxic/anaerobic conditions should be provided for enhanced nitrogen and phosphorus removal. Finally, the biodegradation, bioaccumulation, biosorption, and mass transfer behaviors of the emerging contaminants within the granules need further investigation.

Anaerobic digestion of specified risk materials with cattle manure for biogas production.

Biogas production from anaerobic digestion (AD) of specified risk materials (SRM) co-digested with cattle manure was assessed in a 3 x 2 factorial design. SRM replaced manure at 0 (control), 10% or 25% (w/w) as the substrate fed to six 2-L biodigesters maintained at 37 degrees C or 55 degrees C. Digesters were fed substrate (30 g L(-1) total volatile solids) at 6-d intervals for 90 d, with a retention time of 30 d. Keratin (<20mg) was added to each digester to model the degradation of beta-sheet rich proteins. Methane production was measured daily, and effluent was collected at feeding to monitor SRM degradation using real-time PCR analysis of bovine-specific DNA fragments. Compared with control, methane production increased by 83% or 161% (P<0.05) with 10% or 25% SRM at 37 degrees C, and by 45% and 87%, respectively, at 55 degrees C (P<0.05). Bovine DNA degradation over 6d was higher (P<0.05) at 37 degrees C as compared to 55 degrees C. Dry matter degradation of keratin at 37 degrees C decreased with increasing SRM concentration (P<0.05), whereas at 55 degrees C no difference between treatments was observed (P>0.05). Inclusion of SRM increases the production of methane during the anaerobic digestion of manure and may offer a means of deriving economic value from the disposal of SRM.

Characteristics of suspended solids, microorganisms, and chemical water quality in event-based stormwater runoff from an urban residential area.

Temporal evolution of microbiological, physical, and chemical quality of stormwater runoff from a stormwater drain in an urban residential area in Calgary, Canada, was investigated from May to September, 2006 and 2007. Investigating event mean concentrations and their correlations with rainfall characteristics revealed that intensive rainfall events produced highly polluted stormwater runoff when pollutant source limitation did not occur. Inconsistent event-based correlations between total suspended solids (TSS) concentrations and water quality parameters were observed. During storms, the loading of TSS exhibited a flow-dependent nature, whereas microorganism discharge appeared to be governed by a flow-independent mechanism. No strong first-flush effect was observed in either TSS or microorganisms, on average. No correlations of first-flush loads of TSS with rainfall characteristics were identified. Moderate negative correlations between first-flush loads of microorganisms and rainfall depth and intensity indicated that first flush of microorganisms tended to occur in small storms.

Integrated sampling and analytical approach for common groundwater dissolved gases.

A novel passive gas diffusion sampler (PGDS) combines sampling, storage and direct injection into a single gas chromatograph (GC). The sampler has a 4.5 mL internal volume when deployed, is easy to operate, and eliminates sample-partitioning. The associated GC method analyzes for a large, dynamic sampling range from a single, small volume injection. Dissolved gases were separated on parallel Rt-Molsieve 5A and Rt-Q-PLOT columns and eluted solutes were quantified using a pulse discharge helium ionization detector (PD-HID). The combined sampling and analytical method appears to be less prone to systematic bias than conventional sampling and headspace partitioning and analysis. Total dissolved gas pressure used in tandem with the PGDS improved the accuracy of dissolved gas concentrations. The incorporation of routine measurements of dissolved biogeochemical and permanent gases into groundwater investigations will provide increased insight into chemical and biological processes in groundwater and improve chemical mass balance accuracy.

Field evaluation of mixing length and attenuation of nutrients and fecal coliform in a wastewater effluent plume.

We present an alternative method to dye tracer studies for mapping wastewater effluent plumes in rivers. A case study of a wastewater treatment effluent plume that was mapped in two different months (October and April) showed good resolution in determining where the plume reached the opposite river bank, the degree of mixing in a given river reach, and where the river was fully mixed with respect to the plume. Both electrical conductivity and chloride were useful in mapping domestic wastewater effluent plume mixing. Mixing lengths obtained by field mapping were consistent with previous studies. Electrical conductivity field readings facilitated real-time plume delineation and sampling locations, and identified a non-point source plume during the mapping exercise. The apparent difference in dispersion of the plume between to the two mapping dates (despite similar upstream river discharge) suggests that the calibration of a water quality model based on a single dye test may be inadequate. The river distributions of effluent nutrients and fecal coliform were also mapped. Nutrient attenuation rates were faster than that of the chloride tracer, indicating processes other than mixing occur. Substantial differences were observed in nutrient and fecal coliform distributions between the two mapping dates.

Determination of ethanolamine, ethylene glycol and triethylene glycol by ion chromatography for laboratory and field biodegradation studies.

The determination of alkanolamines and glycols in groundwater and subsurface environments is essential for environmental assessment, remediation and monitoring for selected industrial sites. Monoethanolamine (MEA), ammonium, sodium, magnesium and calcium detection was performed using cation exchange chromatography (IC) with suppressed conductivity detection. Acetate, chloride, nitrite, nitrate, phosphate, sulfate and oxalate were monitored employing anion exchange chromatography with suppressed conductivity. Detection of ethylene glycol (MEG) and triethylene glycol (TEG) and ethanol was carried out using ion exclusion chromatography with pulsed amperometric detection. Effective determination of MEA, MEG and TEG in complex groundwater matrices without compound transformation offered improved monitoring capabilities. This study presents robust analytical tools for MEA, MEG and TEG determination in biodegradation studies. Using ion chromatography offered significant advantages for the analyses of groundwater samples and laboratory bioreactor monitoring.

Toxicity of flare and crude hydrocarbon mixtures.

The toxicity of whole, saturate, and aromatic hydrocarbon mixtures from flare pit and crude oil sources were evaluated using Lumbricus terrestris. Body burden analysis was used to analyze the intrinsic toxicity of the six hydrocarbon mixtures. The major fractions of the whole mixtures, the saturate, and aromatic fractions had different intrinsic toxicities; the aromatics were more toxic than the saturates. The toxicity of the saturate and aromatic fractions also differed between the mixtures. The flare saturate mixture was more toxic than the crude saturate mixture, while the crude aromatic mixture was more toxic than the flare aromatic mixture. The most dramatic difference in toxicity of the two sources was between the flare whole and crude whole mixtures. The crude whole mixture was very toxic; the toxicity of this mixture reflected the toxicity of the crude aromatic fraction. However, the flare whole mixture was not toxic, due to a lack of partitioning from the whole mixture into the lipid membrane of the exposed worms. This lack of partitioning appears to be related to the relatively high concentrations of asphaltenes and polar compounds in the flare pit whole mixture.