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Some of the barriers associated with the land application of biosolids generated in wastewater treatment plants can be eliminated simply by converting the biosolids into biochar using a thermal conversion process called “pyrolysis”. In the current work, eight biosolids from four different wastewater treatment plants in southeast Melbourne, Victoria, Australia were collected and pyrolysed to produce biochars at two different temperatures (500 and 700 °C). In addition, characterisation studies were carried out on the biochars to obtain their physicochemical properties, which were subsequently compared with the properties of the parent biosolids. The major findings of the work demonstrated that biochars exhibited large decreases in DTPA-extractable metals such as Cd, Cu, and Zn, and also led to favorable changes in several chemical and physical characteristics (i.e., pH, Olsen P, electrical conductivity, and surface area) for agricultural land application compared to their original form (i.e., biosolids). Overall, the study suggests that there is great potential for converting biosolids to biochar using pyrolysis. This may not only improve the properties of biosolids for land application, but also has potential to reduce the risk to receiving environments and, furthermore, eliminate many of the costly elements associated with biosolids stockpiling and management.

Applicability of alum addition to wastewater sludge and biosolids produced from different treatment processes was evaluated as a means of odor reduction. Four water resource recovery facilities (WRRFs) were chosen for this study: two used mesophilic anaerobic digestion and two used oxidation ditch processes. The experiments were conducted on a laboratory scale and in all cases the alum was added prior to dewatering. This is the first report of the application of alum for odor reduction in oxidation ditch processes. Alum addition was effective in reducing odors in anaerobically digested biosolids. Addition of 4% alum to anaerobically digested liquid biosolids prior to dewatering resulted in a 60% reduction in the peak odor concentration in the laboratory dewatered cake, relative to the control sample. Alum addition did not reduce odors in dewatered sludge from oxidation ditch processes.

Acute respiratory failure (ARF) is the leading reason for intensive care unit (ICU) admission in patients with cancer. The aim of this study was to identify early predictors of death in patients with cancer admitted to the ICU for ARF who were not intubated at admission. We conducted analysis of a prospective randomized controlled trial including 219 patients with cancer with ARF in which day-28 mortality was a secondary endpoint. Mortality at day 28 was 31.1%. By multivariate analysis, independent predictors of day-28 mortality were: age (odds ratio [OR] 1.30/10 years, 95% confidence interval [CI] [1.01-1.68], p = 0.04), more than one line of chemotherapy (OR 2.14, 95% CI [1.08-4.21], p = 0.03), time between respiratory symptoms onset and ICU admission > 2 days (OR 2.50, 95% CI [1.25-5.02], p = 0.01), oxygen flow at admission (OR 1.07/L, 95% CI [1.00-1.14], p = 0.04) and extra-respiratory symptoms (OR 2.84, 95%CI [1.30-6.21], p = 0.01). After adjustment for the logistic organ dysfunction (LOD) score at admission, only time between respiratory symptoms onset and ICU admission > 2 days and LOD score were independently associated with day-28 mortality. Determinants of death include both factors non-amenable to change, and delay in ARF management. These results suggest that early intensive care management of patients with cancer with ARF may translate to better survival.

This study investigated sources of odours from biosolids produced from a Western Australian wastewater treatment plant and examined possible strategies for odour reduction, specifically chemical additions and reduction of centrifuge speed on a laboratory scale. To identify the odorous compounds and assess the effectiveness of the odour reduction measures trialled in this study, headspace solid-phase microextraction gas chromatography-mass spectrometry (HS SPME-GC-MS) methods were developed. The target odour compounds included volatile sulphur compounds (e.g. dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide) and other volatile organic compounds (e.g. toluene, ethylbenzene, styrene, p-cresol, indole and skatole). In our laboratory trials, aluminium sulphate added to anaerobically digested sludge prior to dewatering offered the best odour reduction strategy amongst the options that were investigated, resulting in approximately 40% reduction in the maximum concentration of the total volatile organic sulphur compounds, relative to control.

To date, no study has been specifically designed to identify determinants of death in neutropenic cancer patients presenting with acute respiratory distress syndrome (ARDS). The aim of this study was to identify early predictive factors of 28-day mortality in these patients. Factors associated with 28-day mortality during intensive care unit (ICU) stay were also described. 70 consecutive cancer patients with ARDS and neutropenia were prospectively analysed over a 6-yr period. Mortality at 28 days was 63%. Factors independently associated with good prognosis were: lobar ARDS (OR 0.10, 95% CI 0.02-0.48), use of initial antibiotic treatment active on difficult to treat bacteria (ticarcillin-resistant Pseudomonas aeruginosa, Stenotrophomonas maltophilia or extended-spectrum β-lactamase-producing strains) (OR 0.08, 95% CI 0.02-0.33) and first-line chemotherapy (OR 0.08, 95% CI 0.02-0.37). During the ICU stay, mortality was associated with the markers of organ dysfunctions, the absence of neutropenia recovery and the use of vasopressors. During the first 3 weeks, the conditional probability of discharge alive from ICU did not decrease. At ICU admission, first-line chemotherapy, lobar ARDS and antibiotic treatment active on difficult-to-treat bacteria were associated with survival. During ICU stay, mortality was associated with organ dysfunctions and use of vasopressors. Most survivors have an ICU stay of >3 weeks.

Introduction: Current guidelines recommend maintaining central venous oxygen saturation (ScvO2) higher than 70% in patients with severe sepsis and septic shock. As high levels of ScvO2 may reflect an inadequate use of oxygen, our aim was to evaluate the relation between maximal ScvO2 levels (ScvO2max) and survival among intensive care unit (ICU) patients with septic shock., Methods: We retrospectively analyzed data from all admissions to our ICU between January 2008 and December 2009. All septic shock patients in whom the ScvO2 was measured were included. The measures of ScvO2max within the first 72 hours after the onset of shock were collected., Results: A total of 1,976 patients were screened and 152 (7.7%) patients met the inclusion criteria. The level of ScvO2max was 85% (78 to 89) in the non-survivors, compared with 79% (72 to 87) in the survivors (P = 0.009)., Conclusions: Our findings raise concerns about high levels of ScvO2 in patients with septic shock. This may reflect the severity of the shock with an impaired oxygen use. Future strategies may target an optimization of tissue perfusion in this specific subgroup of patients.

Due to feedback from students, student abuse during fieldwork, was brought to the attention of the researchers. The study aimed to determine whether a need for a non-abusive intervention programme (NIP) existed amongst the School of Health Care Science students at the University of Pretoria. All students enrolled at the School of Health Care Sciences completed a questionnaire. An overwhelming response indicated that the majority of students (95.85%) have a need for a non-abusive intervention programme (NIP). A significant need was identified especially among Nursing-, Physiotherapy- and Radiography students, 2nd and 4th year students, and within a psychiatric fieldwork setting. Two surprise findings were firstly, that students who have no history of abuse have a greater need for an intervention programme than students with a history of abuse. Secondly superiors in the field are responsible for the majority of abusive incidences reported by students. The implementation of a non-abusive intervention programme (NIP) to help students handle abusive incidences effectively and humanely is strongly recommended.