Sewage sludge as fertiliser - environmental assessment of storage and land application options.

Sewage sludge (SS) contains beneficial plant nutrients and organic matter, and therefore application of SS on agricultural land helps close nutrient loops. However, spreading operations are restricted to certain seasons and hence the SS needs to be stored. Storage and land application of SS are both potential sources of greenhouse gases and ammonia, leading to global warming, acidification and eutrophication. Covering the stored SS, treating it with urea and choosing the correct time for land application all have the potential to reduce emissions from the system. Using life cycle assessment (LCA), this study compares storage and land application options of SS in terms of global warming potential (GWP), acidification potential, eutrophication potential and primary energy use. The system with covered storage has the lowest impact of all categories. Systems with autumn application are preferable to spring application for all impact categories but, when nitrate leaching is considered, spring application is preferable in terms of eutrophication and primary energy use and, for some SS treatments, GWP. Ammonia addition reduces nitrous oxide and ammonia emissions during storage, but increases these emissions after land application. Storage duration has a large impact on GWP, while amount of chemical nitrogen fertiliser substituted has a large impact on primary energy use.

Quality of greywater treated in biochar filter and risk assessment of gastroenteritis due to household exposure during maintenance and irrigation.

AIM: This study evaluated treatment of greywater (GW) by a biochar filter in Jordan and assessed the annual risks of infection (Pi-annual ), annual risk of disease (Pd-annual ) and disease burden (in disability-adjusted life years; DALYs) of gastroenteritis caused by Salmonella spp. and rotavirus due to ingestion of GW during system maintenance and consumption of green onions irrigated with treated and nontreated GW. METHODS AND RESULTS: The biochar filter efficiently removed 93% of biochemical oxygen demand (BOD5 ) and 85% of solids, while removal of Escherichia coli was insignificant. Treatment of GW decreased the median Pd-annual due to ingestion of GW from 1·39 × 10-2 to 6·0 × 10-3 for Salmonella spp. but did not affect Pd-annual caused by rotavirus (9·73 × 10-1 to 1·0). Consumption of onions irrigated with treated GW had a median Pd-annual of 1·25 × 10-9 to 1·2 × 10-8 for Salmonella spp. and 4·96 × 10-4 to 4·37 × 10-3 for rotavirus infection, which was 99·9 and 90% lower, respectively, than the risk when consuming onions irrigated with nontreated GW. The highest risks of gastrointestinal disease were thus associated mainly with direct ingestion of GW when maintaining the system. CONCLUSIONS: Garden produce irrigated with GW treated in biochar filter did not display intolerable risks of rotavirus-based gastroenteritis during summer season in the study area given that the produce is harvested 1 to 2 days, and washed, before consumption. SIGNIFICANCE AND IMPACT OF THE STUDY: This study contributes to scientific-based knowledge on the suitability of biochar filters for onsite greywater treatment and confirms the microbial safety of recycling treated greywater for garden irrigation.

Preferential decoding of emotion from human non-linguistic vocalizations versus speech prosody.

This study used event-related brain potentials (ERPs) to compare the time course of emotion processing from non-linguistic vocalizations versus speech prosody, to test whether vocalizations are treated preferentially by the neurocognitive system. Participants passively listened to vocalizations or pseudo-utterances conveying anger, sadness, or happiness as the EEG was recorded. Simultaneous effects of vocal expression type and emotion were analyzed for three ERP components (N100, P200, late positive component). Emotional vocalizations and speech were differentiated very early (N100) and vocalizations elicited stronger, earlier, and more differentiated P200 responses than speech. At later stages (450-700ms), anger vocalizations evoked a stronger late positivity (LPC) than other vocal expressions, which was similar but delayed for angry speech. Individuals with high trait anxiety exhibited early, heightened sensitivity to vocal emotions (particularly vocalizations). These data provide new neurophysiological evidence that vocalizations, as evolutionarily primitive signals, are accorded precedence over speech-embedded emotions in the human voice.

Wheelchair users' perceived exertion during typical mobility activities.

STUDY DESIGN: Each participant performed a series of wheelchair exercises equivalent in intensity to minimal functional speed (1 m s(-1)), functional walking speed (1.3 m s(-1)), a relatively challenging speed (1.6 m s(-1)) and a self-selected speed. Each participant also completed a graded exercise test (GXT) to volitional exhaustion (VO2peak). OBJECTIVES: The purpose of this study was (1) to assess the physical capacity of wheelchair users as they undertake typical mobility activities and (2) to investigate how closely the components of a differentiated model of perceived exertion mirror wheelchair users' own perception of exertion. METHODS: Eleven (eight males and three females) spinal cord-injured or congenitally impaired wheelchair-dependent participants volunteered for the study. Differentiated ratings of perceived exertion (RPE_arm and RPE_respiration) and oxygen uptake (VO2) and heart rate were recorded during each exercise. RESULTS: The mean comfortable speed at which the participants propelled their own wheelchairs on the wheelchair ergometer was 1.1±0.2 m s(-1). Speeds of 1 m s(-1) and 1.3 m s(-1) are typical of everyday functional propulsion. The corresponding RPE_respiration and RPE_arm ranged from 7 to 13 on the Borg scale; the %VO2peak measured in these trials ranged from 37 to 80% VO2peak. For propulsion intensities used in the present study-low, moderate, high and graded exercise intensity-no difference could be observed between RPE_respiration and RPE_arm. There were no significant differences between RPE_arm and RPE_respiration at the termination of the GXT. CONCLUSION: The current study showed potential for the use of RPE to assess and monitor daily wheelchair propulsion intensity in individuals with paraplegia.

Time course of the influence of musical expertise on the processing of vocal and musical sounds.

Previous functional magnetic resonance imaging (fMRI) studies have suggested that different cerebral regions preferentially process human voice and music. Yet, little is known on the temporal course of the brain processes that decode the category of sounds and how the expertise in one sound category can impact these processes. To address this question, we recorded the electroencephalogram (EEG) of 15 musicians and 18 non-musicians while they were listening to short musical excerpts (piano and violin) and vocal stimuli (speech and non-linguistic vocalizations). The task of the participants was to detect noise targets embedded within the stream of sounds. Event-related potentials revealed an early differentiation of sound category, within the first 100 ms after the onset of the sound, with mostly increased responses to musical sounds. Importantly, this effect was modulated by the musical background of participants, as musicians were more responsive to music sounds than non-musicians, consistent with the notion that musical training increases sensitivity to music. In late temporal windows, brain responses were enhanced in response to vocal stimuli, but musicians were still more responsive to music. These results shed new light on the temporal course of neural dynamics of auditory processing and reveal how it is impacted by the stimulus category and the expertise of participants.

Simulation and verification of hydraulic properties and organic matter degradation in sand filters for greywater treatment.

To evaluate the treatment performance of vertical flow sand filters, the HYDRUS wetland module was used to simulate treatment in an experimental set-up. The laboratory filters were intermittently dosed with artificial greywater at a hydraulic loading rate of 0.032 m³ m⁻² day⁻¹ and an organic loading rate of 0.014 kg BOD5 m⁻² day⁻¹. The hydraulic properties of the filter were characterised, as were inflow and outflow concentrations of chemical oxygen demand (COD), biochemical oxygen demand (BOD), ammonia, nitrate and total nitrogen. The inverse simulation function of the HYDRUS software was used to calibrate the water flow model. The observed effect of water flowing faster along the column wall was included in the inverse simulations. The biokinetic model was calibrated by fitting heterotrophic biomass growth to measurements of potential respiration rate. Emphasis was put on simulating outflow concentrations of organic pollutants. The simulations were conducted using three models of varying degree of calibration effort and output accuracy. The effluent concentration was 245 mg COD L⁻¹ for the laboratory filters, 134 mg COD mg L⁻¹ for the model excluding wall flow effects and 338 mg COD mg L⁻¹ for the model including wall flow effects.

Nitrous oxide production from soils amended with biogas residues and cattle slurry.

The amount of residues generated from biogas production has increased dramatically due to the worldwide interest in renewable energy. A common way to handle the residues is to use them as fertilizers in crop production. Application of biogas residues to agricultural soils may be accompanied with environmental risks, such as increased NO emission. In 24-d laboratory experiments, NO dynamics and total production were studied in arable soils (sandy, clay, and organic) amended with one of two types of anaerobically digested biogas residues (BR-A and BR-B) generated from urban and agricultural waste and nondigested cattle slurry (CS) applied at rates corresponding to 70 kg NH-N ha. Total NO-N losses from the sandy soil were higher after amendment with BR-B (0.32 g NO-N m) than BR-A or CS (0.02 and 0.18 g NO-N m, respectively). In the clay soil, NO-N losses were very low for CS (0.02 g NO-N m) but higher for BR-A and BR-B (0.25 and 0.15 g NO-N m, respectively). In the organic soil, CS gave higher total NO-N losses (0.31 g NO-N m) than BR-A or BR-B (0.09 and 0.08 g NO-N m, respectively). Emission peaks differed considerably between soils, occurring on Day 1 in the organic soil and on Days 11 to 15 in the sand, whereas in the clay the peak varied markedly (Days 1, 6, and 13) depending on residue type. In all treatments, NH concentration decreased with time, and NO concentration increased. Potential ammonium oxidation and potential denitrification activity increased significantly in the amended sandy soil but not in the organic soil and only in the clay amended with CS. The results showed that fertilization with BR can increase NO emissions and that the size is dependent on the total N and organic C content of the slurry and on soil type. In conclusion, the two types of BR and the CS are not interchangeable regarding their effects on NO production in different soils, and, hence, matching fertilizer type to soil type could reduce NO emissions. For instance, it could be advisable to avoid fertilization of organic soils with CS containing high amounts or organic C and instead use BR. In clay soil, however, the risk of NO emissions could be lowered by choosing a CS.

Technology for mobility in SCI 10 years from now.

OBJECTIVES: To identify technological advances and that are likely to have a great impact on the quality of life and participation in individuals with spinal cord injury (SCI). METHODS: In this paper we use the International Classification of Function to frame a discussion on how technology is likely to impact SCI in 10 years. In addition, we discuss the implication of technological advances on future research. RESULTS/CONCLUSION: Although technology advances are exciting, a large challenge for the research community will be how to effectively apply and deploy this technology. Advances occurring in the next 10 years that reduce cost of technology may be more important to the population with SCI than brand new technologies. Social context is everything. As a research community we must advocate for better systems of care. Advocating now for better care will lead to a world in 2020 that is ready to adopt new technologies that are truly transformative.

Changes in the structural and material properties of the tibia in patients with spinal cord injury.

STUDY DESIGN: A cross-sectional study. OBJECTIVES: To measure the change of structural and material properties at different sites of the tibia in spinal cord-injured patients using peripheral quantitative computerised tomography (pQCT). SETTING: Orthopaedic research centre (UK). METHODS: Thirty-one subjects were measured--eight with acute spinal cord injury (SCI), nine with chronic SCI and fourteen able-bodied controls. pQCT scans were performed at 2% (proximal), 34% (diaphyseal) and 96% (distal) along the tibia from the tibial plateau. Structural measures of bone were calculated, and volumetric bone mineral density (vBMD) was also measured at all three levels. Muscle cross-sectional area was measured at the diaphyseal level. RESULTS: Structurally, there were changes in the cortical bone; in the diaphysis, the shape of the cross-section changed to offer less resistance to AP bending, and the cross-sectional area of the cortical shell decreased both proximally and distally. There were corresponding changes in vBMD in the anterior aspect of the cortical diaphysis, as well as proximal and distal trabecular bone. Changes in muscle occurred more rapidly than changes in bone. CONCLUSION: There were clear changes of both structure and material at all three levels of the tibia in chronic SCI patients. These changes were consistent with specific adaptations to reduced local mechanical loading conditions. To assess fracture risk in SCI and also to monitor the effect of therapeutic interventions, the structure of the bone should be considered in addition to trabecular bone mineral density.

Early treatment with zoledronic acid prevents bone loss at the hip following acute spinal cord injury.

UNLABELLED: Osteoporosis after spinal cord injury is common. Reductions in bone density are rapid and fracture rates are higher after injury. Early treatment with 4 mg zoledronic acid significantly reduced bone loss at the hip compared to untreated individuals in the first year. Treatment appeared safe and well tolerated. INTRODUCTION: Bone mineral density (BMD) is lost rapidly following spinal cord injury (SCI), predominantly in the lower limbs. Bone turnover markers suggest an early increase in resorption. METHODS: A randomised, open-label study of 14 patients with acute SCI randomised to receive 4 mg IV zoledronic acid or standard treatment. BMD was measured by dual-X-ray absorptiometry at the lumbar spine and hip (femoral neck, total and trochanter) at baseline, 3, 6 and 12 months. Bone turnover markers (serum C-terminal telopeptide and Procollagen I N-terminal peptide and urinary N-terminal telopeptide/Cr ratio) were also measured. RESULTS: After 12 months, there was a significant difference in BMD between the groups at the total hip (12.4%, p = 0.005), trochanter (13.4%, p = 0.028) and lumbar spine (2.7%, p = 0.033). However, the difference between groups at the femoral neck was not significant (4.8%, p = 0.741). In the treated group, bone resorption was reduced and remained reduced up to 12 months. Other than flu-like symptoms immediately after the infusion, no adverse events were observed. CONCLUSION: IV zoledronic acid is an effective and well-tolerated treatment to prevent bone mineral density loss at the total hip and trochanter for up to 12 months following SCI.

Recognizing vocal expressions of emotion in patients with social skills deficits following traumatic brain injury.

Perception of emotion in voice is impaired following traumatic brain injury (TBI). This study examined whether an inability to concurrently process semantic information (the "what") and emotional prosody (the "how") of spoken speech contributes to impaired recognition of emotional prosody and whether impairment is ameliorated when little or no semantic information is provided. Eighteen individuals with moderate-to-severe TBI showing social skills deficits during inpatient rehabilitation were compared with 18 demographically matched controls. Participants completed two discrimination tasks using spoken sentences that varied in the amount of semantic information: that is, (1) well-formed English, (2) a nonsense language, and (3) low-pass filtered speech producing "muffled" voices. Reducing semantic processing demands did not improve perception of emotional prosody. The TBI group were significantly less accurate than controls. Impairment was greater within the TBI group when accessing semantic memory to label the emotion of sentences, compared with simply making "same/different" judgments. Findings suggest an impairment of processing emotional prosody itself rather than semantic processing demands which leads to an over-reliance on the "what" rather than the "how" in conversational remarks. Emotional recognition accuracy was significantly related to the ability to inhibit prepotent responses, consistent with neuroanatomical research suggesting similar ventrofrontal systems subserve both functions.

Activity and composition of ammonia oxidizing bacterial communities and emission dynamics of NH3 and N2O in a compost reactor treating organic household waste.

AIMS: To monitor emissions of NH(3) and N(2)O during composting and link these to ammonia oxidation rates and the community structure of ammonia oxidizing bacteria (AOB). METHODS AND RESULTS: A laboratory-scale compost reactor treating organic household waste was run for 2 months. NH(3) emissions peaked when pH started to increase. Small amounts of N(2)O and CH(4) were also produced. In total, 16% and less than 1% of the initial N was lost as NH(3)-N and N(2)O-N respectively. The potential ammonia oxidation rate, determined by a chlorate inhibition assay, increased fourfold during the first 9 days and then remained high. Initially, both Nitrosospira and Nitrosomonas populations were detected using DGGE analysis of AOB specific 16S rRNA fragments. Only Nitrosomonas europaea was detected under thermophilic conditions, but Nitrosospira populations re-established during the cooling phase. CONCLUSIONS: Thermophilic conditions favoured high potential ammonia oxidation rates, suggesting that ammonia oxidation contributed to reduced NH(3) emissions. Small but significant amounts of N(2)O were emitted during the thermophilic phase. The significance of different AOBs detected in the compost for ammonia oxidation is not clear. SIGNIFICANCE AND IMPACT OF STUDY: This study shows that ammonia oxidation occurs at high temperature composting and therefore most likely reduces NH(3) emissions.

Changes in soil chemical and microbiological properties during 4 years of application of various organic residues.

A 4-year field trial was established in eastern Sweden to evaluate the effects of organic waste on soil chemical and microbiological variables. A simple crop rotation with barley and oats was treated with either compost from household waste, biogas residue from household waste, anaerobically treated sewage sludge, pig manure, cow manure or mineral fertilizer. All fertilizers were amended in rates corresponding to 100kgNha(-1)year(-1). The effects of the different types of organic waste were evaluated by subjecting soil samples, taken each autumn 4 weeks after harvest, to an extensive set of soil chemical (pH, Org-C, Tot-N, Tot-P, Tot-S, P-AL, P-Olsen, K-AL, and some metals) and microbiological (B-resp, SIR, microSIR active and dormant microorganisms, PDA, microPDA, PAO, Alk-P and N-min) analyses. Results show that compost increased pH, and that compost as well as sewage sludge increased plant available phosphorus; however, the chemical analysis showed few clear trends over the 4 years and few clear relations to plant yield or soil quality. Biogas residues increased substrate induced respiration (SIR) and, compared to the untreated control amendment of biogas residues as well as compost, led to a higher proportion of active microorganisms. In addition, biogas residues increased potential ammonia oxidation rate (PAO), nitrogen mineralization capacity (N-min) as well as the specific growth rate constant of denitrifiers (microPDA). Despite rather large concentrations of heavy metals in some of the waste products, no negative effects could be seen on either chemical or microbiological soil properties. Changes in soil microbial properties appeared to occur more rapidly than most chemical properties. This suggests that soil microbial processes can function as more sensitive indicators of short-term changes in soil properties due to amendment of organic wastes.

A novel approach to bite force measurements in a porcine model in vivo.

A novel device for a bite force measurement system in a porcine model is described. A single polyethylene layer was vacuum-formed into a splint, and a force sensor was fitted on to the splint occlusal surface and seated with a silicone layer. This design enabled the measurement of bite forces on selected teeth in a large animal model with either natural dentition or single implant crowns and could be used in assessing information on biomechanical adaptation of the bone-implant interface to masticatory loads. Preliminary recordings of force values obtained during mastication in the premolar region (200-560 N) and various limiting factors of the technical design are discussed.

The objective measurement of spinal orthosis use for the treatment of adolescent idiopathic scoliosis.

STUDY DESIGN: Technology development and prospective study. OBJECTIVES: Develop instrumentation for discrete, reliable, and objective measurement of brace use patterns between routine follow-ups and without patient involvement. BACKGROUND DATA: To understand spinal bracing efficacy and clinical effectiveness in the conservative treatment of adolescent idiopathic scoliosis, it is essential to measure and record such confounding variables as spinal physiology, force distribution, and compliance. Historically, compliance was measured using patient interviews, pad/strap forces, or temperature. These measurements were subjective, limited to laboratory or short-term monitoring only, required patient intervention, or lacked date/time recording. METHODS: Custom-fitted nonperforated thoracic lumbar sacral orthoses were instrumented with discrete data loggers to measure and record temperature at the skin-brace interface at 16-minute date/time-stamped intervals for up to 88-day periods without patient involvement. Ten female patients (age 15 years, SD 1.2) with adolescent idiopathic scoliosis who had spinal bracing as part of their treatment regimen took part in the study over 14 months, SD 4.5 months. RESULTS: Compliance with the treatment regimen ranged from 8% to 90%, average 65%. Patients tended to overestimate their compliance by 150% (SD 50%). There was no significant difference between weekday and weekend compliance but wear patterns differed. Night wear was significantly greater than day wear (P < 0.01). Patients with very good compliance only removed their brace for washing or exercise periods, but where poor compliance was evident, the brace was only worn sporadically during the day. CONCLUSIONS: Temperature provides a clear signal of the time in brace and can be used for long-term data logging using discrete instrumentation, providing a tool to help identify and understand the reasons behind poor compliance.

Evaluation of mattresses using interface pressure mapping.

OBJECTIVE: To compare the ranking of mattresses using several different performance indices, calculated from interface pressure-mapping data. METHOD: Five mattresses were compared using interface pressure-mapping on 10 healthy volunteers. Mattresses were ranked in order, on the basis of several different specified performance indices. RESULTS: Different performance indices ranked the mattresses in different orders. CONCLUSION: Elaborate performance indices should be used with care, since it is possible to construct a 'tailor-made' performance index to make any chosen mattress rank as the best. Care should be taken to ensure that a performance index is validated, preferably by some demonstrated link to clinical outcomes.

Quantitative measurement of spinal brace use and compliance in the treatment of adolescent idiopathic scoliosis.

The objective measurement of compliance with spinal bracing in adolescents with idiopathic scoliosis (AIS) is fundamental in the validation of clinical trials of bracing effectiveness, and in helping clinicians better understand reasons behind poor compliance. Current technology has been developed and tested for discrete, reliable and objective measurement of the times of day a brace is worn and consistency in its use. TLSOs were instrumented with data loggers measuring temperature at the skin/brace interface at 16 minutes intervals over a period of 88 days; between routine follow up and without patient interference. 10 female patients (age 14 years, sd 1.1) with AIS using spinal bracing as part of their treatment regime took part in the study over 15 months. Skin/brace interface temperature during periods of wear in the UK was >30 degrees C, ambient 23 degrees C, sd 4. Compliance ranged from 8-90%, average 65%. Patients tended to over estimate their compliance by 150% (sd 50%). There was no significant difference between weekday and weekend compliance but wear patterns differed. Nightwear was significantly greater than daywear. Patients with very good compliance only removed their brace for washing or exercise periods but where poor compliance was evident, the brace was only worn sporadically during the day. Temperature provides a clear signal of brace use and can be used for long-term data logging using discrete instrumentation, providing a tool to help identify and understand the reasons behind poor compliance.

Early recurrence from stereotactic aspiration of a colloid cyst of the third ventricle.

The case of a 66 year old woman who underwent successful stereotactic aspiration of a symptomatic colloid cyst of the third ventricle, but who had recurrence after only 5 weeks, is presented. Stereotactic aspiration is a well established technique for the treatment of colloid cysts, however disagreement exists regarding its efficacy. Two factors, both from pre-operative CT, help to predict success from aspiration: the cyst's density and size. The literature reports that recurrence after successful stereotactic aspiration should not occur for many years.

The effect of compressed speech on the ability of right-hemisphere-damaged patients to use context.

The ability of RHD patients to use context under conditions of increased processing demands was examined. Subjects monitored for words in auditorily presented sentences of three context types-normal, semantically anomalous, and random, at three rates of speech normal, 70% compressed (Experiment 1) and 60% compressed (Experiment 2). Effects of semantics and syntax were found for the RHD and normal groups under the normal rate of speech condition. Using compressed rates of speech, the effect of syntax disappeared, but the effect of semantics remained. Importantly, and contrary to expectations, the RHD group was similar to normals in continuing to demonstrate an effect of semantic context under conditions of increased processing demands. Results are discussed relative to contemporary theories of laterality, based on studies with normals, that suggest that the involvement of the left versus right hemisphere in context use may depend upon the type of contextual information being processed.