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The Oxford handbook of Greek and Roman mythography
\"This introduction provides an overview of the contents of the present volume but also attempts to situate the information and arguments of the individual chapters in the context of Greek and Roman mythographical studies today, which have changed dramatically in the last three decades. Additionally, a brief survey of the shifting modes of mythography in antiquity is presented. While a simple exposition is impossible and a complete overarching theory and definition cannot be provided, we note how many of the contributions point toward mythography as a mental orientation or intellectual impulse rather than a clear-cut genre\"-- Provided by publisher.
BOOK
The link between organic matter composition and the biogas yield of full-scale sewage sludge anaerobic digestion
The principal parameters influencing anaerobic digestion (AD) of sewage sludge have been extensively studied in controlled laboratory experiments, but the effects of sludge composition on full-scale systems have received relatively little attention. Sludge samples from eight major wastewater treatment plants (WWTPs) in the UK were examined to determine the effects of sludge composition on digestion performance. The biogas yield (BY) was estimated by two different methods: (1) a standard approach based on the reduction in volatile solids (VS), and (2) a more detailed mass balance of major constituent fractions of organic matter in sludge. The results showed that BY increased significantly with the overall amount of VS contained in digester feed sludge. In terms of the effects of individual fractions, BY was significantly related to and increased with the fat and cellulose contents in raw sludge, consistent with the high calorific value of fat and the digestibilities of both substrates, relative to the other major organic components. The results demonstrated the importance of sludge composition on digester performance and strategies to maximise BY were identified, for instance, by increasing codigestion of high fat containing substrates, and by utilising fat, oil and grease collected in-sewer and at WWTP.
Journal Article
Cross-Linked Enzyme Aggregate (CLEA) Preparation from Waste Activated Sludge
Enzymes are used extensively as industrial bio-catalysts in various manufacturing and processing sectors. However, commercial enzymes are expensive in part due to the high cost of the nutrient medium for the biomass culture. Activated sludge (AS) is a waste product of biological wastewater treatment and consists of microbial biomass that degrades organic matter by producing substantial quantities of hydrolytic enzymes. Recovering enzymes from AS therefore offers a potential alternative to conventional production techniques. A carrier-free, cross-linked enzyme aggregate (CLEA) was produced from crude AS enzyme extract for the first time. A major advantage of the CLEA is the combined immobilization, purification, and stabilization of the crude enzymes into a single step, thereby avoiding large amounts of inert carriers in the final enzyme product. The AS CLEA contained a variety of hydrolytic enzymes and demonstrated high potential for the bio-conversion of complex organic substrates.
Journal Article
Interventional factors influencing natural killer cell immunity in colorectal cancer: a systematic review
Background and aim
Colorectal cancer (CRC) is the third most common cancer globally. Despite advances in curative CRC surgery, metastatic disease remains a significant problem. Emerging evidence suggests that several commonly used perioperative interventions may influence cancer immunity through natural killer (NK) cell function or numbers. This systematic review aimed to identify the effects of standard perioperative interventions on NK cells in CRC patients.
Methods
A systematic search of four databases, MEDLINE, EMBASE, Cochrane Library and Scopus was performed up to 30th July 2024 using keywords associated with colorectal cancer, NK cells and perioperative medications. PRISMA guidelines were followed. Critical appraisal was undertaken using the Joanna Briggs Institute Critical Appraisal tools for quasi-experimental studies and randomised controlled trials.
Results
The literature search identified 10,404 titles and abstracts for screening. Of these, 226 full-text papers were reviewed, and 16 studies were included for data extraction. Results were presented in a narrative synthesis due to study heterogeneity.
In vivo
studies consistently demonstrated a post-operative decrease in overall cytotoxic capacity and number of NK cells compared to pre-operative levels. This effect was observed across all examined medications, including fentanyl, morphine, propofol and oxycodone. Additionally, blood transfusion also resulted in decreased NK cell cytotoxicity and activity in CRC patients.
Conclusion
While surgical stress is one of the significant factor influencing NK cell cytotoxicity, this review indicates that perioperative intervention also contributes to decreased NK cell cytotoxicity. Our findings demonstrate that certain perioperative interventions (such as ketamine and morphine) can negatively impact NK cell cytotoxicity.
Journal Article
Predicting outcome of patients with chest wall injury
Rib fractures occur in 10% of injured patients, are associated with morbidity and mortality, and frequently necessitate intensive care unit (ICU) care. A scoring system that identifies the risk for respiratory failure early in the evaluation process may allow early intervention to improve outcomes. The aim of this study was to test the hypothesis that a scoring system based on initial clinical findings can identify patients with rib fractures at greatest risk for morbidity and mortality.
A simple scoring system to stratify risk was developed and applied to patients through a retrospective trauma registry review. Points were assigned as follows: age < 45 years = 1 point, age 45 to 65 years = 2 points, age > 65 years = 3 points; <3 fractures = 1 point, 3 to 5 fractures = 2 points, >5 fractures = 3 points; no pulmonary contusion = 0 points, mild pulmonary contusion = 1 point, severe pulmonary contusion = 2 points, bilateral pulmonary contusion = 3 points; and bilateral rib fracture absent = 0 points, bilateral rib fracture absent present = 2 points. A review of trauma registry patients with rib fractures (June 2008 to February 2010) at a state-designated level 1 trauma center was performed. Data reviewed included age, number of fractures, bilateral injury, presence of pulmonary contusion, classification of the contusion, length of hospital stay, mechanical ventilation, ICU admission, and length of stay. The scoring system was retrospectively applied to 649 patients to determine validity.
A score ≤ 7 indicated lower mortality (24 of 579 [4.2%]) compared with patients with scores > 7 (10 of 70 [14.3%]) (Fisher's 2-sided P = .0018). Patients with scores ≤ 6 were less likely to be admitted to an ICU (29.7%) compared with those with scores ≥ 7 (56.7%) (P < .0001). Patients with total scores < 7 were less likely to require intubation (20.6%) compared with those with scores ≥ 7 (40.0%) (P < .0001). Patients with scores ≤ 4 had shorter lengths of stay (36.0% <5 days) compared with those who had scores > 4 (59.7%) (P < .0001).
A simple scoring system predicts the likelihood that patients will require mechanical ventilation and prolonged courses of care. A score of 7 or 8 predicted increased risk for mortality, admission to the ICU, and intubation. A score > 5 predicted a longer length of stay and a longer period of ventilation. This scoring system may assist in the earlier implementation of treatment strategies such epidural anesthesia, ventilation, and operative fixation of fractures.
Journal Article
Organic Contaminant Biodegradation by Oxidoreductase Enzymes in Wastewater Treatment
Organic contaminants (OCs), such as pharmaceuticals, personal care products, flame retardants, and plasticisers, are societally ubiquitous, environmentally hazardous, and structurally diverse chemical compounds whose recalcitrance to conventional wastewater treatment necessitates the development of more effective remedial alternatives. The engineered application of ligninolytic oxidoreductase fungal enzymes, principally white-rot laccase, lignin peroxidase, and manganese peroxidase, has been identified as a particularly promising approach for OC remediation due to their strong oxidative power, broad substrate specificity, low energy consumption, environmental benignity, and cultivability from lignocellulosic waste. By applying an understanding of the mechanisms by which substrate properties influence enzyme activity, a set of semi-quantitative physicochemical criteria (redox potential, hydrophobicity, steric bulk and pKa) was formulated, against which the oxidoreductase degradation susceptibility of twenty-five representative OCs was assessed. Ionisable, compact, and electron donating group (EDG) rich pharmaceuticals and antibiotics were judged the most susceptible, whilst hydrophilic, bulky, and electron withdrawing group (EWG) rich polyhalogenated compounds were judged the least susceptible. OC susceptibility scores were in general agreement with the removal rates reported for experimental oxidoreductase treatments (R2 = 0.60). Based on this fundamental knowledge, and recent developments in enzyme immobilisation techniques, microbiological enzymic treatment strategies are proposed to formulate a new generation of biological wastewater treatment processes for the biodegradation of environmentally challenging OC compounds.
Journal Article
Venous thromboembolic prophylaxis: current practice of surgeons in Australia and New Zealand for major abdominal surgery
Background
Surgical prophylaxis for venous thrombo-embolic disease (VTE) includes risk assessment, chemical prophylaxis and mechanical prophylaxis (graduated compression stockings [GCS]
and/or
intermittent pneumatic compression devices [IPCD]). Although there is overwhelming evidence for the need and efficacy of VTE prophylaxis in patients at risk, only about a third of those who are at risk of VTE receive appropriate prophylaxis.
Objective
There is debate as to the best combination of VTE prophylaxis following abdominal surgery due to lack of evidence. The aim of this survey was to understand this gap between knowledge and practice.
Methods
In 2019 and 2020, a survey was conducted to investigate the current practice of venous thromboembolism (VTE) prophylaxis for major abdominal surgery, with a focus on colorectal resections. The study received ethics approval and involved distributing an 11-item questionnaire to members of two professional surgical societies: the Colorectal Surgical Society of Australia and New Zealand (CSSANZ) and the General Surgeons Australia (GSA).
Results
From 214 surgeons: 100% use chemical prophylaxis, 68% do not use a risk assessment tool, 27% do not vary practice according to patient risk factors while > 90% use all three forms of VTE prophylaxis at some stage of treatment. Most surgeons do not vary practice between laparoscopic and open colectomy/major abdominal surgery and only 33% prescribe post-discharge chemical prophylaxis. 42% of surgeons surveyed had equipoise for a clinical trial on the use of IPCDs and the vast majority (> 95%) feel that IPCDs should provide at least a 2% improvement in VTE event rate in order to justify their routine use.
Conclusion
Most surgeons in Australia and New Zealand do not use risk assessment tools and use all three forms of prophylaxis regardless. Therfore there is a gap between practice and VTE prophylaxis for the use of mechanical prophylaxis options. Further research is required to determine whether dual modality mechanical prophylaxis is incrementally efficacious.
Trial Registration-
Not Applicable.
Journal Article
Enzyme Recovery from Biological Wastewater Treatment
Enzymes are high value industrial bio-catalysts with extensive applications in a wide range of manufacturing and processing sectors, including the agricultural, food and household care industries. The catalytic efficiency of enzymes can be several orders higher compared to inorganic chemical catalysts under mild conditions. However, the nutrient medium necessary for biomass culture represents a significant cost to industrial enzyme production. Activated sludge (AS) is a waste product of biological wastewater treatment and consists of microbial biomass that degrades organic matter by producing substantial quantities of hydrolytic enzymes. Therefore, enzyme recovery from AS offers an alternative, potentially viable approach to industrial enzyme production. Enzyme extraction from disrupted AS flocs is technically feasible and has been demonstrated at experimental-scale. A critical review of disruption techniques identified sonication as potentially the most effective and suitable method for enzyme extraction, which can be scaled up and is a familiar technology to the water industry. The yields of different enzymes are influenced by wastewater treatment conditions, and particularly the composition, and can also be controlled by feeding sludge with specific target substrates. Nevertheless, hydrolytic enzymes can be effectively extracted directly from waste AS without specific modifications to standard wastewater treatment processes. Purification, concentration and stabilisation/immobilisation techniques can also greatly expand the industrial application and increase the economic value and marketability of enzyme products extracted from AS. Concentrated and purified AS enzymes could readily substitute inorganic and/or commercial bioenzyme catalysts in many industrial applications including, for example, leather processing, and in detergent and animal feed formulation. Enzyme extraction from AS therefore offers significant economic benefits to the Water Industry by recovering valuable resources from wastewater. They can also optimise important waste treatment processes, such as the anaerobic digestion (AD) of sewage sludge, increasing biogas and renewable energy production. The enzyme-extracted sludge exhibits improved treatment properties, such as increased settleability, dewaterability, and anaerobic digestibility for biogas production, assisting sludge management by wastewater treatment plants (WWTPs) and enabling the further utilisation of the residual sludge.
Graphic Abstract
Journal Article
Effect of Time to Operation on Value of Care in Acute Care Surgery
Background
As reimbursement models evolve, there is increasing emphasis on maximizing value-based care for inpatient conditions. We hypothesized that longer intervals between admission and surgery would be associated with worse outcomes and increased costs for acute care surgery patients, and that these associations would be strongest among patients with high-risk conditions.
Methods
We performed a 5-year retrospective analysis of three risk cohorts: appendectomy (low-risk for morbidity and mortality,
n
= 618), urgent hernia repair (intermediate-risk,
n
= 80), and laparotomy for intra-abdominal sepsis with temporary abdominal closure (sTAC; high-risk,
n
= 102). Associations between the interval from admission to surgery and outcomes including infectious complications, mortality, length of stay, and hospital charges were assessed by regression modeling.
Results
Median intervals between admission and surgery for appendectomy, hernia repair, and sTAC were 9.3, 13.5, and 8.1 h, respectively, and did not significantly impact infectious complications or mortality. For appendectomy, each 1 h increase from admission to surgery was associated with increased hospital LOS by 1.1 h (
p
= 0.002) and increased intensive care unit (ICU) LOS by 0.3 h (
p
= 0.011). For hernia repair, each 1 h increase from admission to surgery was associated with increased antibiotic duration by 1.6 h (
p
= 0.007), increased hospital LOS by 3.3 h (
p
= 0.002), increased ICU LOS by 1.5 h (
p
= 0.001), and increased hospital charges by $1918 (
p
< 0.001). For sTAC, each 1 h increase from admission to surgery was associated with increased antibiotic duration by 5.0 h (
p
= 0.006), increased hospital LOS by 3.9 h (
p
= 0.046), increased ICU LOS by 3.5 h (
p
= 0.040), and increased hospital charges by $3919 (
p
= 0.002).
Conclusions
Longer intervals from admission to surgery were associated with prolonged antibiotic administration, longer hospital and ICU length of stay, and increased hospital charges, with strongest effects among high-risk patients. To improve value of care for acute care surgery patients, operations should proceed as soon as resuscitation is complete.
Journal Article