The Incidence of Amyotrophic Lateral Sclerosis in Ohio 2016-2018: The Ohio Population-Based ALS Registry.

INTRODUCTION: Amyotrophic lateral sclerosis (ALS) is a fatal, neuromuscular disease with no cure. ALS incidence rates have not been assessed specifically in Ohio, yet the state contains both metropolitan and rural areas with a variety of environmental factors that could contribute to disease etiology. We report the incidence of ALS in Ohio residents diagnosed from October 2016 through September 2018. METHODS: We engaged practitioners from 9 Ohio sites to identify newly diagnosed ALS patients and to complete case report forms with demographic and clinical information. ALS was diagnosed according to the Awaji criteria and classified as either definite, probable, or possible. We developed a method to estimate missing cases using a Poisson regression model to impute cases in counties with evidence of undercounting. RESULTS: We identified 333 newly diagnosed ALS patients residing in Ohio during the 2-year index period and found incidence rates varied in the 88 state counties. After incorporating the estimated 27% of missing cases, the corrected crude annual incidence was 1.96/100,000 person-years, and the age- and gender-standardized incidence was 1.71/100,000 person-years (standardized to the 2010 US census). DISCUSSION/CONCLUSION: The estimated Ohio incidence of ALS is overall similar to that reported in other states in the USA. This study reveals a geospatial variation in incidence within the state, and areas with higher rates warrant future investigation.

Risk factors for amyotrophic lateral sclerosis: A regional United States case-control study.

Most amyotrophic lateral sclerosis (ALS) cases are considered sporadic, without a known genetic basis, and environmental exposures are thought to play a causal role. To learn more about sporadic ALS etiology, we recruited n = 188 ALS patients from northern New England and Ohio and matched controls 2:1 from the general population of the same regions. Questionnaires evaluated the association between a variety of lifestyle, behavioral (ie, hobbies and activities), and occupational factors and the risk of ALS, including the duration of time between exposure and ALS onset, and exposure frequency. Head trauma was associated with increased ALS risk (adjusted odds ratio [OR] 1.60 95% confidence interval [CI] 1.04-2.45), with significantly greater effects for injuries occurring 10 or more years prior to symptom onset (P = .037). ALS risk was increased for those reporting severe electrical burns (adjusted OR 2.86, 95% CI 1.37-6.03), with odds ratios highest for burns after age 30 (OR 3.14), and for burns 10 or more years prior to symptom onset (OR 3.09). Hobbies involving lead were the most strongly associated with ALS risk (adjusted OR 2.92, 95% CI 1.45-5.91). Exposures to lead 20 or more years prior to diagnosis had larger effect sizes compared to those occurring more recently. Holding a job in mechanics, painting, or construction was associated with ALS. The identification of these specific environmental factors associated with ALS highlight the need for future prospective and laboratory studies to assess causality, biological mechanisms, and find prevention or treatment opportunities.

Salmonellosis Outbreak Detected by Automated Spatiotemporal Analysis - New York City, May-June 2019.

In May 2019, the New York City Department of Health and Mental Hygiene (NYCDOHMH) detected an unusual cluster of five salmonellosis patients via automated spatiotemporal analysis of notifiable diseases using free SaTScan software (1). Within 1 day of cluster detection, graduate student interviewers determined that three of the patients had eaten prepared food from the same grocery store (establishment A) located inside the cluster area. NYCDOHMH initiated an investigation to identify additional cases, establish the cause, and provide control recommendations. Overall, 15 New York City (NYC) residents with laboratory-diagnosed salmonellosis who reported eating food from establishment A were identified. The most commonly consumed food item was chicken, reported by 10 patients. All 11 clinical isolates available were serotyped as Salmonella Blockley, sequenced, and analyzed by core genome multilocus sequence typing; isolates had a median difference of zero alleles. Environmental assessments revealed food not held at the proper temperature, food not cooled properly, and potential cross-contamination during chicken preparation. Elevated fecal coliform counts were found in two of four ready-to-eat food samples collected from establishment A, and Bacillus cereus was detected in three. The outbreak strain of Salmonella was isolated from one patient's leftover chicken. Establishing automated spatiotemporal cluster detection analyses for salmonellosis and other reportable diseases could aid in the detection of geographically focused, community-acquired outbreaks even before laboratory subtyping results become available.

Thermal Degradation of Long Chain Fatty Acids.

The thermal hydrolysis of saturated (C16:0 and C18:0) and unsaturated fatty acids (C16:1, C18:1, and C18:2) was investigated at 90 °C to 160 °C for 30 min and 8 h durations. Hydrolysis efficiencies were calculated based on mass yield (i.e., mg/g parent compound), which accounted for all C2-C24 by-products. Very little degradation (less than 1%) of long chain fatty acids (LCFAs) was observed from 30 min thermal hydrolysis. At 140 and 160 °C for 8 h, saturated fatty acids degraded uniformly to C2 to C14. Saturated fatty acids tended to convert to alkanes (1.5-2.0% of total fatty acids) instead of fatty acids (8 h). Thermal hydrolysis did not significantly affect unsaturated LCFA degradation at any duration. The unsaturated by-products seen were the result of cleavage at the allylic or vinylic positions. Thermal hydrolysis of LCFAs with digested sludge was investigated. The amount of VFAs and LCFAs in primary and secondary sludge was increased at 140 and 160 °C as a result of lipid degradation in the sludge mixture. Thermal hydrolysis of fatty acids with different catalysts was also investigated. Whereas saturated LCFAs were stable under all catalytic conditions, unsaturated LCFAs were nearly completely degraded when hydrolyzed with hydrogen peroxide and activated carbon or copper sulfate.

Effect of High Strength Food Wastes on Anaerobic Codigestion of Sewage Sludge.

Anaerobic codigestion has been practiced at water resource recovery facilities to increase methane production, but the impact of many variables is still not well understood. In this study, the feasibility of codigesting fats, oils, and grease (FOG), and other high strength wastes (HSWs) with municipal sewage sludge was investigated. Four laboratory-scale digesters were operated at a working volume of 9.75 L, 15 days solids retention time (SRT), and at a temperature of 37 °C. Wastes including whey (cheese), juice, grease trap waste (GTW), and dissolved air flotation waste (DAF), along with municipal sewage sludge, were fed to the digesters in varying amounts. The addition of HSWs led to higher methane production at lower organic loadings. However, at higher organic loadings, the GTW appeared to be toxic to methanogens, leading to a decrease in digester pH and biogas production, and an accumulation of volatile fatty acids within the digester.

Nitrogen Removal in a Staged Anaerobic-Aerobic Sludge Digestion System.

A mixture of primary and secondary municipal sludge was treated in the digestion system consisting of a first-stage mesophilic anaerobic and a second-stage aerobic digester. The study was to monitor solids and nitrogen removal efficiencies under different operational conditions in the aerobic digester.In the first phase, the aerobic digester was batch fed under continuous aeration. More solids and ammonia were removed as the aerobic retention time increased. About 90% or greater ammonia was removed at 3 days or longer aerobic retention times. However, higher oxidized nitrogen was measured at the longer aeration times.In the second phase, the aerobic digestion system was operated for 3 to 5 days while continuously fed with anaerobically digested sludge under different intermittent aeration times. About 90% ammonia removal and low effluent oxidized nitrogen were achieved at 40 minutes of aeration over a 60-minute cycle at a 4-day retention time.

Novel Stokesian Metrics that Quantify Collision Efficiency, Floc Strength, and Discrete Settling Behavior.

Novel parameters were developed to predict the effluent quality and settling behavior in clarifiers that cannot conventionally be achieved using either the conventional flux theory or overflow rates. Simple batch experiments based on the critical settling velocity (CSV) selection were used as the basis for the development of three novel parameters: intrinsic settling classes (ISC), threshold of flocculation/flocculation limitation (TOF/α), and floc strength. ISC was proven to accurately (±2%) determine the granule fraction and discrete particle distribution. TOF quantified the minimum solids concentration needed to form large flocs and was directly linked to collision efficiency. In hybrid systems, an exponential fitting on a CSV matrix was proposed to quantify the collision efficiency of flocs (α). Shear studies were conducted to quantify floc strength. The methods were applied to a wide spectrum of sludge types to show the broad applicability and sensitivity of the novel methods.

Reverse flexing as a physical/mechanical treatment to mitigate fouling of fine bubble diffusers.

Achieving energy neutrality has shifted focus towards aeration system optimization, due to the high energy consumption of aeration processes in modern advanced wastewater treatment plants. A study on fine bubble diffuser fouling and mitigation, quantified by dynamic wet pressure (DWP), oxygen transfer efficiency and alpha was carried out in Blue Plains, Washington, DC. Four polyurethane fine bubble diffusers were installed in a pilot reactor column fed with high rate activated sludge from a full scale system. A mechanical cleaning method, reverse flexing (RF), was used to treat two diffusers (RF1, RF2), while two diffusers were kept as a control (i.e., no reverse flexing). There was a 45% increase in DWP of the control diffuser after 17 months of operation, an indication of fouling. RF treated diffusers (RF1 and RF2) did not show significant increase in DWP, and in comparison to the control diffuser prevented about 35% increase in DWP. Hence, reverse flexing potentially saves blower energy, by reducing the pressure burden on the air blower which increases blower energy requirement. However, no significant impact of the RF treatment in preventing a decrease in alpha-fouling (αF) of the fine pore diffusers, over time in operation was observed.

Acidogenesis and Two-Phase Codigestion of Fats, Oils, and Greases and Municipal Biosolids.

Acidogenic codigestion of fats, oils, and greases (FOG) was studied using suspended growth sludge digesters operated as batch fed reactors that were fed twice daily. The digesters were maintained at a 2-day retention time and at 37 °C to mimic the acid phase of an acid-gas digestion system. As FOG loading rates increased, volatile fatty acid (VFA) production was found to increase, although the percentage of VFA production compared to theoretical values decreased exponentially to just 20% at the highest loading rates. FOG matter was found to have accumulated in the reactor vessel in semi-solid balls that floated near the liquid surface. Two-phase codigestion of FOG was studied at 37 °C using Continuously Stirred Tank Reactors (CSTRs) as acid phase digesters (APD) operated with 2-day retention times, followed by gas phase digesters (GPD) with 15-day retention times. The two-phase systems were compared by FOG addition to the APD versus GPD. FOG addition to the APD resulted in 88% destruction of LCFAs, whereas FOG addition to the GPD resulted in 95% destruction of LCFAs. Accumulated LCFAs were found in the APD receiving FOG and were primarily composed palmitic acid (16:0), followed by oleic acid (18:1) and stearic acid (18:0).

Laboratory evaluation of suspected motor neuron disease: A survey of physicians.

INTRODUCTION: The clinical diagnosis of amyotrophic lateral sclerosis (ALS) relies on exclusion of mimic syndromes, but there are no specific guidelines regarding the extent of laboratory testing required. METHODS: A survey was sent to 274 physicians listed in the Neuromuscular Section of the American Academy of Neurology. The survey asked how often they order 21 different laboratory tests in patients suspected of having ALS. RESULTS: Ninety-nine responses were received (36% response rate). Greater than 75% ordered serum creatine kinase, chemistry panel, and thyroid functions often or always. Fewer than 25% tested for serum complement, hexosaminidase A, spinal muscular atrophy, Kennedy disease, heavy metals, or human T-cell lymphotrophic virus often or always. Twelve other tests had intermediate responses. CONCLUSIONS: There is a lack of consensus among respondents regarding the laboratory evaluation of suspected ALS. Prospective studies are needed to define the diagnostic yield and cost-effectiveness of laboratory testing in this population.

Impact of substrate feed patterns on solids reduction by the Cannibal process.

A biological solids reduction process that uses a side-stream anaerobic reactor (Cannibal process) was investigated to better understand why variations in solids reduction occur in field installations. Field observations indicated that single stage, high sludge age processes would frequently not provide a low solids yield. To study this, laboratory sequencing batch reactors were operated, one as a conventional activated sludge system and the other two with a side-stream anaerobic reactors. The control and one anaerobic side-stream system were operated with a 5-minute feed cycle to mimic a plug flow system. The other anaerobic side-stream system operated with a 4-hour feed cycle to simulate complete mix. The 5 minutes feed Cannibal system generated up to 80%. less biological solids than the control. The 4 hours feed Cannibal system produced less biological solids than the conventional activated sludge system but remained higher than for system with a 5-minute feed time.

Effects of nitrate input from a water reclamation facility on the Occoquan Reservoir water quality.

To manage water quality in the Occoquan Reservoir, Virginia, a water reclamation facility discharges nitrified product water that reduces the release of undesirable substances (e.g., phosphorus, iron, and ammonia) from sediments during periods of hypolimnetic anoxia. Results showed that when the oxidized nitrogen (OxN) concentration input to the reservoir was lower than 5 mg N/L during periods of anoxia following thermal stratification, nitrate was depleted in the upper reaches of the reservoir resulting in the release of ammonia and orthophosphate from the sediments downstream. When the OxN input to the reservoir was operationally increased to a concentration greater than 10 mg-N/L, orthophosphate release was suppressed. Introducing OxN to the system decreased sediment ammonia release but did not eliminate it. By discharging reclaimed water that contained nitrate levels greater than 10 mg N/L, reservoir water quality was protected and the discharged nitrate was converted to nitrogen gas as it moved downstream.

Variation in organic matter characteristics of landfill leachates in different stabilisation stages.

This study investigates the effect of landfill age on landfill leachate characteristics; two aspects are focused here. One is ultraviolet absorbance at 254 nm (UV(254)) property, as the discharge of landfill leachates to publically owned treatment works can cause interference with UV(254) disinfection. The other is biorefractory organic nitrogen in leachates, as it can contribute to effluent nitrogen making it difficult to meet stringent effluent nitrogen regulations. To study variation in UV(254)-absorbing organic carbon and organic nitrogen, leachate samples ranging from cells with ages 2 to 30 y from a large landfill in Kentucky, were collected and fractionated on a basis of their molecular weight and chemical nature into humic acids, fulvic acids and a hydrophilic fraction. The effectiveness of long term landfilling and membrane treatment for organic matter and organic nitrogen removal was examined. Humic materials, which were the major UV(254)-absorbing substances, were mainly >1 kDa and they degraded significantly with landfill age. The hydrophilic organic fraction, which was the major contributor to organic nitrogen, was mainly <1 kDa and it became increasingly recalcitrant with landfill age. This study provides insight into the characteristics of the different leachate fractions with landfilling age that might aid the design of on-site leachate treatment techniques.

Effect of silver nanoparticles and antibiotics on antibiotic resistance genes in anaerobic digestion.

Water resource recovery facilities have been described as creating breeding ground conditions for the selection, transfer, and dissemination of antibiotic resistance genes (ARGs) among various bacteria. The objective of this study was to determine the effect of direct addition of antibiotic and silver nanoparticles (Ag NPs, or nanosilver) on the occurrence of ARGs in thermophilic anaerobic digesters. Test thermophilic digesters were amended with environmentally-relevant concentrations of Ag NP (0.01, 0.1, and 1.0 mg-Ag/L; corresponding to approximately 0.7, 7.0, and 70 mg-Ag/kg total solids) and sulfamethoxazole (SMX) that span susceptible to resistant classifications (1, 5, and 50 mg/L) as potential selection pressures for ARGs. Tetracycline (tet(O), tet(W)) and sulfonamide (sulI, sulII) ARGs and the integrase enzyme gene (intI1) associated with Class 1 integrons were measured in raw sludge, test thermophilic digesters, a control thermophilic digester, and a control mesophilic digester. There was no apparent effect of Ag NPs on thermophilic anaerobic digester performance. The maximum SMX addition (50 mg/L) resulted in accumulation of volatile fatty acids and low pH, alkalinity, and volatile solids reduction. There was no significant difference between ARG gene copy numbers (absolute or normalized to 16S rRNA genes) in amended thermophilic digesters and the control thermophilic digester. Antibiotic resistance gene copy numbers in digested sludge ranged from 10(3) to 10(6) copies per microL (approximately 8 x10(1) to 8 x 10(4) copies per microg) of sludge as result of a 1-log reduction of ARGs (2-log reduction for intI1). Quantities of the five ARGs in raw sludge ranged from 10(4) to 10(8) copies per microL (approximately 4 x 10(2) to 4 x 10(6) per microg) of sludge. Test and control thermophilic digesters (53 degrees C, 12-day solids retention time [SRT]) consistently reduced but did not eliminate levels of all analyzed genes. The mesophilic digester (37 degrees C, 20-day SRT) also reduced levels of sulI, sulII, and intI1 genes, but levels of tet(O) and tet(W) were the same or higher than in raw sludge. Antibiotic resistance gene reductions remained constant despite the application of selection pressures, which suggests that digester operating conditions are a strong governing factor of the bacterial community composition and thus the prevalence of ARGs.

The effect of direct addition of iron(III) on anaerobic digestion efficiency and odor causing compounds.

The role of iron addition to sewage sludge prior to anaerobic digestion was evaluated to determine the effect of iron on digestion performance and generation of odor-causing compounds. Hydrogen sulfide (H2S) and volatile organic sulfur compounds (VOSCs) were the odorous gases evaluated in this study. Samples were obtained from seven municipal wastewater treatment plants (WWTPs), and batch anaerobic digestion tests were conducted using primary and secondary sludges at 30 day solids retention time (SRT) under mesophilic conditions. Volatile solid removal (VSR) was highly predictable with background iron concentrations measured in the combined sludge. They were likely to increase as influent iron content increased. 1.25% w/w ferric chloride (FeCl3) was added to the anaerobic digester feed in order to simulate iron addition for sulfide control in full-scale WWTPs. The results showed that it had a positive impact on digestion performance with higher VSR and odor control with reduced H2S and TVOSCs in the headspace gas of dewatered biosolids considered in the tests. Ferric chloride is considered a beneficial additive as a strategy for an odor mitigation, not to mention more efficient digestion under anaerobic conditions.

Effect of various sludge digestion conditions on sulfonamide, macrolide, and tetracycline resistance genes and class I integrons.

Wastewater treatment processes are of growing interest as a potential means to limit the dissemination of antibiotic resistance. This study examines the response of nine representative antibiotic resistance genes (ARGs) encoding resistance to sulfonamide (sulI, sulII), erythromycin (erm(B), erm(F)), and tetracycline (tet(O), tet(W), tet(C), tet(G), tet(X)) to various laboratory-scale sludge digestion processes. The class I integron gene (intI1) was also monitored as an indicator of horizontal gene transfer potential and multiple antibiotic resistance. Mesophilic anaerobic digestion at both 10 and 20 day solids retention times (SRTs) significantly reduced sulI, suII, tet(C), tet(G), and tet(X) with longer SRT exhibiting a greater extent of removal; however, tet(W), erm(B) and erm(F) genes increased relative to the feed. Thermophilic anaerobic digesters operating at 47 °C, 52 °C, and 59 °C performed similarly to each other and provided more effective reduction of erm(B), erm(F), tet(O), and tet(W) compared to mesophilic digestion. However, thermophilic digestion resulted in similar or poorer removal of all other ARGs and intI1. Thermal hydrolysis pretreatment drastically reduced all ARGs, but they generally rebounded during subsequent anaerobic and aerobic digestion treatments. To gain insight into potential mechanisms driving ARG behavior in the digesters, the dominant bacterial communities were compared by denaturing gradient gel electrophoresis. The overall results suggest that bacterial community composition of the sludge digestion process, as controlled by the physical operating characteristics, drives the distribution of ARGs present in the produced biosolids, more so than the influent ARG composition.

Digestion performance of various combinations of thermophilic and mesophilic sludge digestion systems.

Various combinations of single- and multi-stage anaerobic and aerobic-anaerobic digestion systems were studied to evaluate their solids reduction potential with capabilities to control sulfur-based biosolids odor compounds. All the multi-stage digestion systems removed more volatile solids than the single-stage anaerobic digestion systems, even at the same overall retention time. However, digestion systems with mesophilic digestion as the final stage showed a much lower headspace organic sulfur content in the dewatered biosolids than the systems with thermophilic digestion as the final stage. This observation leads to the conclusion that placing a mesophilic anaerobic digestion system at the end of multi-stage digestion systems will enable greater sulfur-based odor reduction from dewatered biosolids with greater solid reduction than single-stage mesophilic or thermophilic digestion systems.

Combined anaerobic/aerobic digestion: effect of aerobic retention time on nitrogen and solids removal.

A combined anaerobic/aerobic sludge digestion system was studied to determine the effect of aerobic solids retention time (SRT) on its solids and nitrogen removal efficiencies. After the anaerobic digester reached steady state, effluent from the anaerobic digester was fed to aerobic digesters that were operated at 2- to 5-day SRTs. The anaerobic system was fed with a mixture of primary and secondary sludge from a local municipal wastewater treatment plant. Both systems were fed once per a day. The aerobic reactor was continuously aerated with ambient air, maintaining dissolved oxygen level at 1.1 +/- 0.3 mg/L. At a 4-day or longer SRT, more than 11% additional volatile solids and 90% or greater ammonia were removed in the aerobic digester, while 32.8 mg-N/L or more nitrite/nitrate also was measured. Most total Kjeldahl nitrogen removal was via ammonia removal, while little organic nitrogen was removed in the aerobic digester.

Effect of feeding patterns on the performance of activated sludge systems.

Excessive amounts of monovalent cations are known to cause deterioration in settling and dewatering properties of activated sludge. In this study, variations in the feeding pattern to a sequencing batch reactor (SBR) were evaluated to determine if the feed pattern could influence effluent quality and sludge characteristics under high monovalent cation concentrations. Data showed that deflocculation caused by high concentrations of sodium could be mitigated by using a feed cycle where the influent to the SBR was provided over a period of 1 minute. In contrast, when the feed was provided over 4 hours, deterioration in settling and effluent water quality was observed, as reflected by an increase in effluent suspended solids, effluent chemical oxygen demand, and capillary suction time.

Anaerobic digestion of raw and thermally hydrolyzed wastewater solids under various operational conditions.

In this study, high-solids anaerobic digestion of thermally pretreated wastewater solids (THD) was compared with conventional mesophilic anaerobic digestion (MAD). Operational conditions, such as pretreatment temperature (150 to 170 degrees C), solids retention time (15 to 20 days), and digestion temperature (37 to 42 degrees C), were varied for the seven THD systems operated. Volatile solids reduction (VSR) by THD ranged from 56 to 62%, compared with approximately 50% for MAD. Higher VSR contributed to 24 to 59% increased biogas production (m3/kg VSR-d) from THD relative to MAD. The high-solids conditions of the THD feed resulted in high total ammonia-nitrogen (proportional to solids loading) and total alkalinity concentrations in excess of 14 g/L as calcium carbonate (CaCO3). Increased pH in THD reactors caused 5 to 8 times more un-ionized ammonia to be present than in MAD, and this likely led to inhibition of aceticlastic methanogens, resulting in accumulation of residual volatile fatty acids between 2 and 6 g/L as acetic acid. The THD produced biosolids cake that possessed low organic sulfur-based biosolids odor and dewatered to between 33 and 39% total solids. Dual conditioning with cationic polymer and ferric chloride was shown to be an effective strategy for mitigating dissolved organic nitrogen and UV-quenching compounds in the return stream following centrifugal dewatering of THD biosolids.