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Anaerobic digestion (AD) is a long-established method for treating wastewater sludge and has been extensively researched, but there remains a lack of generic or practical modelling tools to guide operators and maximise the energy output. Detailed kinetic models have been developed, but are too complex as practical tools for industrial level application. A multi-level model of biogas yield (BY) was therefore developed based on operational data from 72 full-scale sites in the UK showing a wide range of AD performance. The model focused on the controllable operational parameters that are currently monitored at full-scale, including: temperature, hydraulic retention time and dry solids content in the feed sludge. The model effectively described performance variations in BY of full-scale processes, and provides a practical management tool to aid decision support to improve AD efficiency and net energy balance. Image 1 • Up to 7 years of operational data from 72 full-scale AD sites was examined. • A practical, operationally based sewage sludge MAD biogas model was developed. • AD performance was significantly correlated to major operational process variables. • Effects of operational parameters on BY with THP are equivalent to conventional MAD. • Optimisation strategies are proposed to improve the overall AD energy balance. [ABSTRACT FROM AUTHOR]

Background: Adequate post‐operative analgesia is essential for recovery following abdominal surgery. Abdominal wall nerve blocks have been shown to be beneficial in this respect following surgery. The purpose of this trial was to examine the efficacy of infusional versus intermittent bolus delivery of abdominal wall blocks in patients undergoing abdominal resectional gastrointestinal surgery. Methods: A prospective randomized clinical trial, involving 120 patients undergoing gastrointestinal surgery, was undertaken across three hospitals. Insertion of abdominal wall catheters was performed and patients were randomized to receive ropivacaine 0.2% by either continuous infusion or regular intermittent bolus. The primary outcome was respiratory function, as measured by spirometry on post‐operative days 1–3 and 30. Secondary outcomes were pain, mobility, return of gut function, length of hospital stay, complication rates and patient satisfaction with analgesia. Results: All 120 patients were followed up to trial completion. Patients were well matched with regards to demographics. There was no difference between groups with regards to the primary outcome of post‐operative respiratory function. The bolus group had improved mobility scores on post‐operative day 1 (P = 0.025). There were no complications associated with blockade, and no other differences were identified between assessed outcomes. Conclusions: Continuous infusion and intermittent bolus are both safe ways of delivering abdominal wall nerve blockade, with equivalent analgesic outcomes. Bolus delivery appears to provide superior early mobility in comparison with continuous infusion. [ABSTRACT FROM AUTHOR]

Background: Anastomotic leakage is a feared complication following colorectal surgery. Early prediction results in improved clinical outcome, but accurate predictive factors remain elusive. Many biomarkers have been studied with respect to diagnosis of anastomotic leakage but the concept of trajectory testing, using biomarkers, has not been assessed with regards to early diagnosis of anastomotic leak. Methods: C‐reactive protein (CRP), procalcitonin (PCT), white cell count (WCC) and gamma‐glutamyl transferase were assessed for predictive utility in diagnosing anastomotic leakage with emphasis on identifying an association with change in their levels or trajectory. Levels were collected preoperatively and daily for the first 5 post‐operative days on patients undergoing elective colorectal surgery, involving an anastomosis. Anastomotic leakage was defined clinically by operative or radiological intervention. Comparison was made between biomarkers and clinical anastomotic leakage, using receiver operator characteristic curves for logistic models, based on trajectory of the four biomarkers. Results: A total of 197 consecutive patients were analysed. Eleven patients developed clinical anastomotic leakage. An association of biomarker trajectory with anastomotic leakage was observed for WCC, PCT and CRP, but not for gamma‐glutamyl transferase. CRP was the superior biomarker based on trajectory, with area under the receiver operator curve of 0.961. Conclusion: This study identifies change in CRP, WCC and PCT as potential markers of anastomotic leakage following colorectal surgery and in particular highlights CRP trajectory as extremely accurate in diagnosing anastomotic leakage requiring intervention. External validation should be sought before incorporating this into routine clinical practice, given the numbers in this study. [ABSTRACT FROM AUTHOR]

Objectives: To determine the potential of novel gradient echo parameters, "Black Bone" MRI as an alternative to CT in the identification of normal and prematurely fused cranial sutures both in 2D and 3D imaging.Methods: Thirteen children with a clinical diagnosis of craniosynostosis underwent "Black Bone" MRI in addition to routine cranial CT. "Black Bone" datasets were compared to CT and clinical findings. "Black Bone" imaging was subsequently used to develop 3D reformats of the craniofacial skeleton to enhance further visualisation of the cranial sutures.Results: Patent cranial sutures were consistently identified on "Black Bone" MRI as areas of increased signal intensity. In children with craniosynostosis the affected suture was absent, whilst the remaining patent sutures could be visualised, consistent with CT and clinical findings. Segmentation of the "Black Bone" MRI datasets was successful with both threshold and volume rendering techniques. The cranial sutures, where patent, could be visualised throughout their path.Conclusions: Patent cranial sutures appear as areas of increased signal intensity on "Black Bone" MRI distinct from the cranial bone, demonstrating considerable clinical potential as a non-ionising alternative to CT in the diagnosis of craniosynostosis.Key Points: • Patent cranial sutures appear hyperintense on "Black Bone" MRI • Prematurely fused cranial sutures are distinct from patent sutures • Minimal soft tissue contrast permits 3D-rendered imaging of the craniofacial skeleton. [ABSTRACT FROM AUTHOR]

The article investigates the efficacy, adverse effects, and cost of antibiotic treatment of acute mild to moderate sinusitis. A survey of medical literature was conducted to determine the frequency of acute sinusitis. A search was made to identify meta-analyses published in the last ten years of randomized controlled trials comparing antibiotics with placebo for treating acute sinusitis. Sinusitis is one the most common primary care diagnoses and accounts for up to 21 percent of prescriptions.

Abstract: A broad spectrum of organic chemicals is essential to modern society. Once discharged from industrial, domestic and urban sources into the urban wastewater collection system they may transfer to the residual solids during wastewater treatment and assessment of their significance and implications for beneficial recycling of the treated sewage sludge biosolids is required. Research on organic contaminants (OCs) in biosolids has been undertaken for over thirty years and the increasing body of evidence demonstrates that the majority of compounds studied do not place human health at risk when biosolids are recycled to farmland. However, there are 143,000 chemicals registered in the European Union for industrial use and all could be potentially found in biosolids. Therefore, a literature review of ‘emerging’ OCs in biosolids has been conducted for a selection of chemicals of potential concern for land application based upon human toxicity, evidence of adverse effects on the environment and endocrine disruption. To identify monitoring and research priorities the selected chemicals were ranked using an assessment matrix approach. Compounds were evaluated based upon environmental persistence, human toxicity, evidence of bioaccumulation in humans and the environment, evidence of ecotoxicity and the number and quality of studies focussed on the contaminant internationally. The identified chemicals of concern were ranked in decreasing order of priority: perfluorinated chemicals (PFOS, PFOA); polychlorinated alkanes (PCAs), polychlorinated naphthalenes (PCNs); organotins (OTs), polybrominated diphenyl ethers (PBDEs), triclosan (TCS), triclocarban (TCC); benzothiazoles; antibiotics and pharmaceuticals; synthetic musks; bisphenol A, quaternary ammonium compounds (QACs), steroids; phthalate acid esters (PAEs) and polydimethylsiloxanes (PDMSs). A number of issues were identified and recommendations for the prioritisation of further research and monitoring of ''emerging'' OCs for the agricultural use of biosolids are provided. In particular, a number of ‘emerging’ OCs (PFOS, PFOA and PCAs) were identified for priority attention that are environmentally persistent and potentially toxic with unique chemical properties, or are present in large concentrations in sludge, that make it theoretically possible for them to enter human and ecological food-chains from biosolids-amended soil. [Copyright &y& Elsevier]

The content, behaviour and significance of heavy metals in composted waste materials is important from two potentially conflicting aspects of environmental legislation in terms of: (a) defining end-of-waste criteria and increasing recycling of composted residuals on land and (b) protecting soil quality by preventing contamination. This review examines the effects of heavy metals in compost and amended soil as a basis for achieving a practical and sustainable balance between these different policy objectives, with particular emphasis on agricultural application. All types of municipal solid waste (MSW) compost contain more heavy metals than the background concentrations present in soil and will increase their contents in amended soil. Total concentrations of heavy metals in source-segregated and greenwaste compost are typically below UK PAS100 limits and mechanical segregated material can also comply with the metal limits in UK PAS100, although this is likely to be more challenging. Zinc and Pb are numerically the elements present in the largest amounts in MSW-compost. Lead is the most limiting element to use of mechanically-segregated compost in domestic gardens, but concentrations are typically below risk-based thresholds that protect human health. Composted residuals derived from MSW and greenwaste have a high affinity for binding heavy metals. There is general consensus in the scientific literature that aerobic composting processes increase the complexation of heavy metals in organic waste residuals, and that metals are strongly bound to the compost matrix and organic matter, limiting their solubility and potential bioavailability in soil. Lead is the most strongly bound element and Ni the weakest, with Zn, Cu and Cd showing intermediate sorption characteristics. The strong metal sorption properties of compost produced from MSW or sewage sludge have important benefits for the remediation of metal contaminated industrial and urban soils. Compost and sewage... [Copyright &y& Elsevier]

Abstract: A small-scale, intensively sampled laboratory batch experiment was performed to characterize isothermal inactivation profiles of enteric organisms at representative mesophilic, thermophilic and pasteurization temperatures adopted for the treatment of sewage sludge. The chemical environment of the heating matrix significantly influenced exponential decay rates when enteric bacterial populations were thermally stressed. The behaviour of Escherichia coli and Salmonella under mesophilic conditions appeared to be related to the retention time and, to a limited extent, the sample matrix, but there was no evidence of direct thermal inactivation taking place at mesophilic temperatures. [Copyright &y& Elsevier]

Abstract: Linear alkylbenzene sulphonate (LAS) is used at a rate of approximately 430000 tons/y in Western Europe, mainly in laundry detergents. It is present in sewage sludge (70–5600mg/kg; 5–95th percentile) because of its high usage per capita, its sorption and precipitation in primary settlers, and its lack of degradation in anaerobic digesters. Immediately after amendment, calculated and measured concentrations are <1 to 60mg LAS/kg soil. LAS biodegrades rapidly in soil with primary and ultimate half-lives of up to 7 and 30 days, respectively. Calculated residual concentrations after the averaging time (30 days) are 0.24–18mg LAS/kg soil. The long-term ecotoxicity to soil microbiota is relatively low (EC10 ⩾26mg sludge-associated LAS/kg soil). An extensive review of the invertebrate and plant ecotoxicological data, combined with a probabilistic assessment approach, led to a PNEC value of 35mg LAS/kg soil, i.e. the 5th percentile (HC5) of the species sensitivity distribution (lognormal distribution of the EC10 and NOEC values). Risk ratios were identified to fall within a range of 0.01 (median LAS concentration in sludge) to 0.1 (95th percentile) and always below 0.5 (maximum LAS concentration measured in sludge) according to various scenarios covering different factors such as local sewage influent concentration, water hardness, and sewage sludge stabilisation process. Based on the present information, it can be concluded that LAS does not represent an ecological risk in Western Europe when applied via normal sludge amendment to agricultural soil. [Copyright &y& Elsevier]

Assessing medical student competence in non-traditional domains can be challenging. Conventional methods of assessment are generally unsatisfactory. The authors discuss the approach taken at the Brown Medical School, USA to assess students at the beginner, intermediate, and advanced levels in the social and community contexts of health care - one of the nine abilities that comprise Brown's competency-based curriculum. At the beginner level, faculty use weekly field notes written by students about their experiences in community practice placements as the means for assessment. At the intermediate level, faculty assess students based on their completion of a project focused on a community health problem. At the advanced level, a screening process is used in which students first meet individually with a member of the assessment committee who determines if the student's efforts appear to meet the expected standards. If success seemed likely, then the student was encouraged to appear before the whole committee. The authors discuss the common use of subjective judgments at all three levels and the importance of diverse perspectives in achieving a consensus. Allowing students wide latitude in expressing themselves and their accomplishments helps to ensure success. [ABSTRACT FROM AUTHOR]

The article offers information on endogenous bacterial and fungal endogenous endophthalmitis (EE). EE is caused by the spread of bacterial or fungal organisms to eye. Predisposing factors that make patients susceptible to EE include intravenous hyperalimentation, intravenous or indwelling catheter and antibiotic therapy. Diagnostic aspect in cases of EE, medical treatment and surgical treatment of EE are discussed.

Slow sand filtration (SSF) is widely used throughout the world for the treatment of drinking water. However, relatively little attention has been given to the development of a comprehensive process model. Previous studies have considered separate aspects of the SSF process, such as developing an improved representation of the schmutzdecke layer, and a more detailed description of the microbial dynamics. The objective of this work was to develop a deterministic simulation model of the SSF process incorporating fundamental physicochemical and biological dynamics within a classical filtration framework. The model was based on a temporal and spatial finite difference method and was calibrated and verified using operational data from pilot-scale SSF units. Results from the calibration showed that the model satisfactorily predicts headloss development in SSF units. There was no significant difference between many of the most sensitive model parameter values for two successive runs of the same filter. However, a few individual model parameters (e.g., in the fundamental headloss equations) were found to vary with filtration run and it is speculated that this is due to seasonal factors. [ABSTRACT FROM AUTHOR]

This paper describes the use of a deterministic slow sand filter process model to investigate and assess some of the fundamental aspects and mechanisms operating during slow sand filtration (SSF). These include the role of the schmutzdecke, biomass development, and the initial condition of the filter, to the overall process performance. The SSF process model has been developed recently and is described in a companion paper by Campos et al., in 2006. It attempts to provide a simulation of the physicochemical and biological processes responsible for the filtration mechanisms operating in SSF. The simulation of filter runs has been carried out with the help of extensive pilot plant data provided by Thames Water Utilities Ltd., involving both uncovered and covered filter beds. The results demonstrate that the presence and nature of a schmutzdecke layer profoundly influence the spatial and temporal development of interstitial biomass within the sand and, consequently, the headloss profile. Microbial interactions in the filter bed play a fundamental role in the process and are involved in setting the pattern and magnitude of headloss development. The model also demonstrates the significance of residual deposits within the filter after surface cleaning, on the subsequent filter behavior. [ABSTRACT FROM AUTHOR]

Computed tomography has played a key role in bone structure imaging for over two decades. However, when a metal implant is present in the sample, the reconstructions are seriously distorted by artifact, and no method has successfully met the clinical demands. This paper presents a new method for metal artifact reduction in Computed Tomography based on sinusoidal description with the concentration of clinical applications. A piece of pig's leg with a lead nail placed inside the bone was scanned, generating 224 slices, in 177 of which the metal implant was present. The method includes detection of the correspondence of metal implants, fitting, amendment, and reconstruction based on sinusoidal description. Simulation and statistical error analysis show that the method improves PSNR (Peak Signal-to-Noise Ratio). A 3D modeling based on the reconstruction using the sinusoidal amendment method for a real case demonstrates that most of the metal artifact has been removed, which is compared with that based on the default output of the scanner. Metal artifacts in CT can be reduced effectively by the method based on the sinusoidal description, which isolates the correspondence of a metal implant from the original projection, so that a high quality reconstruction can be obtained. [ABSTRACT FROM AUTHOR]

A new description for computed tomography, parallel and equal to Radon transformation but based on sinusoidal functions rather than line integrals, is introduced. This representation contributes an effective algorithm to reduce metal artefacts in reconstruction. Using this method, the information included in the scan data corresponding to the metal implants can be separated from the original projection, an amending method rather than interpolation is therefore provided to reach higher accuracy for reconstruction. The method is with low complexity in computation, and can be combined online with filtered backprojection (FBP), which is the most widely used algorithm in practice, to improve the quality of the reconstructed image. Also, the method has the potential to deal with the artefacts caused by beam hardening and partial volume, and to be developed into a straight reconstruction algorithm based on the sinusoidal representation. Examples are presented for clearer description and demonstration. [ABSTRACT FROM AUTHOR]

Part II. Focuses on the development of a competency-based curriculum, known as MD2000. Reasons for developing the curriculum; How it was developed; Details on the curriculum; Significance for medical education.

The preservation of small, independent family practices within a changed health care delivery environment is a goal worth pursuing. Properly organized, such practices would maintain the special fiduciary relationship between physicians and patients. Fundholding practices, which are a growing organizational form of general practice in the United Kingdom, are described as a model that could serve as the basis for an American alternative to corporate medicine. [ABSTRACT FROM AUTHOR]

Aim: The gastrointestinal bile acid (BA)/microbiota axis has emerged as a potential mediator of health and disease, particularly in relation to pathologies such as inflammatory bowel disease (IBD) and colorectal cancer. Whilst it presents an exciting new avenue for therapies, it has not yet been characterized in surgical resection of the ileum, where BA reabsorption occurs. The identification of BA/microbiota signatures may provide future therapies with perioperative personalized medicine. In this work we conduct a systematic review with the aim of investigating the microbiome and BA changes that are associated with resection of the ileum. Method: The databases included were MEDLINE, EMBASE, Web of Science and Cochrane libraries. The outcomes of interest were faecal microbiome and BA signatures after ileal resection. Results: Of the initial 3106 articles, three studies met the inclusion/exclusion criteria for data extraction. A total of 257 patients (46% surgery, 54% nonsurgery controls) were included in the three studies. Two studies included patients with short bowel syndrome and the other included patients with IBD. Large‐scale microbiota changes were reported. In general, alpha diversity had decreased amongst patients with ileal surgery. Phylum‐level changes included decreased Bacteroidetes and increased Proteobacteria and Fusobacteria in patients with an intestinal resection. Surgery was associated with increased total faecal BAs, cholic acid and chenodeoxycholic acid. There were decreases in deoxycholic acid and glycine and taurine conjugated bile salts. Integrated BA and microbiota data identified correlations with several bacterial families and BA. Conclusion: The BA/microbiota axis is still a novel area with minimal observational data in surgery. Further mechanistic research is necessary to further explore this and identify its role in improving perioperative outcomes. [ABSTRACT FROM AUTHOR]

• Grazing livestock ingest PTEs in biosolids-amended grassland. • Ingested Cd does not transfer to muscle tissue in significant concentrations. • Cd may accumulate in offal but concentrations are below food limit values. When biosolids are applied to agricultural soil, potentially toxic elements (PTEs) accumulate in the topsoil, although it takes many repeated applications to reach soil limit values. Two programmes of UK government-funded research were commissioned in the 1990s to investigate the transfer of PTEs to the food chain via ingestion by sheep grazing biosolids-amended soil. Here, we critically re-examine this evidence in the light of other published work and current food quality standards. This was particularly motivated by the need to determine the safety of biosolids controls on PTEs in relation to revised and stricter European food quality controls for PTEs in foodstuffs. The major pathway for transfer of PTEs to grazing livestock is via direct ingestion of biosolids or biosolids-amended soil from the soil surface. The main elements of concern for the human diet are cadmium (Cd) and lead (Pb), with Cd being the focus of the current paper. Animal ingestion of plant tissue is also a potential pathway for Cd exposure, which, unlike Pb, can transfer to crop tissues. The concentrations of Cd in the muscle tissue of sheep grazing biosolids-amended soil were generally small and similar to control values. Cadmium concentrations in sheep offal were below the maximum permitted concentration for human consumption. This was despite ingestion of soils exceeding the maximum permissible concentration for Cd in soil (3 mg kg−1 dry soil) by up to three times, at an ingestion rate of 10% total dietary dry matter intake. Grazing trials under practical conditions on high Cd soils demonstrated that the Cd concentrations in sheep offal remained below the food limit value for this element in offal from the combined intakes from biosolids-amended soil and herbage. Futhermore, given the substantial fall in environmental emissions and concentrations in biosolids of this element and, consequently, it cannot accumulate in soil to the limit value, biosolids Cd does not represent an issue for the safety of animal meat products. [ABSTRACT FROM AUTHOR]

At laparotomy, an enormous cyst arising from the sigmoid mesentery and extending into the mesorectum was identified that was intricately related to the sigmoid colon, pushing it into the right upper quadrant. Computed tomography (CT) of the abdomen and pelvis demonstrated a large cystic mass in the pelvis and central abdomen measuring 24 × 19 × 12 cm displacing the sigmoid colon anteriorly and the bladder posteroinferiorally. A 58-year-old female presented with a 4-week history of intermittent dull right-sided abdominal pain, mild nausea and a sensation of incomplete bladder emptying upon micturition. [Extracted from the article]

Background: Surgical Site Infection (SSI) of the abdominal incision is a dreaded complication following colorectal surgery. Identifying the intraoperative surgical site microbes may provide clarity in the pathogenesis of SSIs. Genomic sequencing has revolutionized the ability to identify microbes from clinical samples. Utilization of 16S rRNA amplicon sequencing to characterize the intraoperative surgical site may provide the critical information required to predict and prevent infection in colorectal surgery. Methods: This is a pilot, prospective observational study of 50 patients undergoing elective colorectal resection. At completion of surgery, prior to skin closure, swabs were taken from the subcutaneous tissue of the abdominal incision to investigate the microbial profile. Dual swabs were taken to compare standard culture technique and 16S rRNA sequencing to establish if a microbial profile was associated with postoperative SSI. Results: 8/50 patients developed an SSI, which was more likely in those undergoing open surgery (5/15 33.3% versus 3/35, 8.6%; P = 0.029). 16S rRNA amplicon sequencing was more sensitive in microbial detection compared to traditional culture. Both culture and 16S rRNA demonstrated contamination of the surgical site, predominantly with anaerobes. Culture was not statistically predictive of infection. 16S rRNA amplicon sequencing was not statistically predictive of infection, however, it demonstrated patients with an SSI had an increased biodiversity (not significant) and a greater relative abundance (not significant) of pathogens such as Bacteroidacaea and Enterobacteriaceae within the intraoperative site. Conclusions: 16S rRNA amplicon sequencing has demonstrated a potential difference in the intraoperative microbial profile of those that develop an infection. These findings require validation through powered experiments to determine the overall clinical significance. [ABSTRACT FROM AUTHOR]

Background: Surgical site infection remains a significant cause of morbidity and mortality. Traditionally, the causation has been inferred from the organism(s) detected in the post-operative setting. However, the intra-operative surgical site and the bacteria it harbors have been scarcely studied. Compared with culture-dependent methods, the development of genomic technology provides a new sensitive tool that could aid in characterizing the bacteria within the surgical site. The purpose of this literature review is to establish if there is a predictive role of sampling the intra-operative surgical site. Methods: A systematic literature review was conducted identifying relevant literature reporting on studies that sampled the intra-operative surgical site of any specialty, using either traditional culture or a culture-independent genomic sequencing-based technique and correlation with infection was attempted. The review identified studies between 1959 and 2021 in MEDLINE, EMBASE and Cochrane. Results: The initial search identified 7,835 articles; 36 remained after screening. Thirty-one articles focused on culture-dependent techniques, five on culture-independent. Subgroup meta-analysis demonstrates that a positive intra-operative culture carries a risk of downstream infection with an odds ratio of 8.6, however limited by a high false-positive and inability to correlate the intra-operative culture with the post-operative infection. In contrast, culture-independent studies through genomic sequencing are not predictive but suggest that the surgical incision is a complex microbial community with a shift toward dysbiosis in certain patients. Conclusion: The intra-operative surgical site clearly harbors bacteria. Both techniques give rise to separate explanations underpinning the role of bacteria in surgical site infection. It is possible there is a more complex dynamic community within the incision that makes a patient susceptible to infection. Characterizing this microbial community in large scale studies, including patients with infections may enhance our ability to predict and prevent incisional surgical site infections in patients undergoing surgical procedures. [ABSTRACT FROM AUTHOR]

Background: The presence of an indwelling urinary catheter (IDUC) is routine following colorectal resections. In Enhanced Recovery After Surgery programmes, excessive intravenous fluids (IVFs) are avoided. This study sought to determine whether the routine absence of an IDUC following colorectal surgery improved post‐operative outcomes and minimized fluid prescription. Methods: A retrospective comparative cohort study was performed on patients undergoing colorectal resection at a tertiary referral teaching hospital, over a 7‐year period. A policy of no routine IDUC was introduced over the last 3 years. Patients were divided into cohorts based on the presence or absence of an IDUC on leaving the operating theatre. The outcomes assessed were IVF prescription, length of stay, mortality and morbidity. Results: Of the 213 resections over the time period, 131 met the inclusion criteria (87 IDUC and 44 no IDUC). There was no difference between groups with respect to baseline demographics. Fluid administration was less in the group without routine IDUC (total fluid 6.16 L versus 10.89 L; P < 0.0001, fluid in the first 24 h 3.82 L versus 5.3 L; P < 0.0001 and fluid in the first 48 h 5.15 L versus 7.23 L; P < 0.0001). Length of stay was less in the ‘no IDUC’ group (5.9 days versus 10.1 days; P = 0.0009). There was no difference in morbidity and mortality. Conclusion: A policy of no IDUC following colectomy was associated with a reduction in IVF administration and length of stay. A randomized controlled trial is recommended in order to more accurately determine the degree of causal relationship. [ABSTRACT FROM AUTHOR]

Uncontrolled burning of municipal solid waste (MSW) is an important source of air pollution and is wide spread in many developing countries, but only limited data quantify the extent of domestic open burning of household waste. Here, we present some of the first field data to be reported on the uncontrolled domestic burning of waste. A representative community of Mexico (Huejutla de Reyes Municipality) was investigated and household surveys, interviews with waste operators and a waste characterisation analysis were completed to assess the extent of, and factors controlling, the open burning of waste. Waste collection provision to rural communities was very limited and, consequently 92% of households in rural areas reported that they disposed of waste by uncontrolled burning in backyards or unofficial dumps. Overall, 24% of the total MSW generated in the Municipality was disposed by uncontrolled burning. Urban and periurban areas received twice-weekly collections and the rate of uncontrolled burning was considerably smaller compared to rural households, corresponding to approximately 2% of total waste generation. Carbon equivalency calculations showed that burning waste in backyards represented approximately 6% of the total and 8.5% of fuel related CO 2 Eq emissions by the municipality. Moreover, the equivalent carbon dioxide (CO 2 Eq) from black carbon (BC) emitted by uncontrolled burning in backyards was over fifteen times larger compared to methane (CH 4 ) potentially released from equivalent amounts of combustible biodegradable waste disposal at the official dumpsite. An assessment of local respiratory health data showed the incidence of disease was higher in rural than in urban areas, when the opposite trend is typically observed in the international literature; given the high rate of burning activity found in rural areas we suggest that open burning of waste could be a major reason for the apparent poorer respiratory health status of the rural population and requires further investigation. The results emphasise the importance of including BC from uncontrolled burning of waste in international emission inventories of greenhouse gases and in the assessment of the health status of local communities in developing countries where this practice is prevalent. [ABSTRACT FROM AUTHOR]

The author discusses the challenges confronting medical practitioners when adhering to evidence-based guidelines and a medical approach that physicians can apply when confronted with resistance from a patient. He explains that practitioners are more inclined to providing patient-centered care. He encourages physicians to determine the true concerns of their patients and to provide them with information from which their rationale is based. The author also proposes a treatment contingency plan.

The article discusses the preservation of arteriovenous (AV) access during the management of clinically significant arterial steal to restore perfusion to the distal extremity. It is noted that the preservation of AV access can be accomplished by relieving proximal arterial lesions. It also highlights the role of arterial stenosis in the development of distal ischemia. According to the authors, arterial steal poses a problem among patients on chronic hemodialysis.

The article suggests ways medical schools in the U.S. can enhance the number of their graduates and produce primary care physicians. One of the alternatives that the author mentions is to enable advanced practice nurses and physician assistants to assume a greater role in offering primary care. He adds that medical schools should recognize the factors that discourage students from pursuing careers in primary care.

Reports on a case of lipohyperplasia of the ileo-caecal valve in a 48-year-old man who presented with appendicitis. Findings of the physical examination; Histopathology of the caecal lesion; Modes of clinical presentation.

Background: Sarcopenia has been shown to have significant adverse health outcomes in a range of patient populations. Particularly, sarcopenic patients having cancer surgery are a unique group who demonstrate poorer post‐operative outcomes. Currently, the gold standard in diagnosing sarcopenia is through the use of computed tomography. However, the widespread use of imaging to diagnose patients with sarcopenia is neither cost‐effective nor practical. Identifying a serum biomarker or a simple mobility scoring system as an alternative diagnostic tool may aid in identifying more patients at risk of sarcopenia. C1q, a novel biomarker, has previously been shown to correlate with sarcopenia. Similarly, we sought to explore whether mobility scores may provide a useful surrogate marker for sarcopenia. Methods: This was a prospective cohort study of patients who presented for colorectal cancer surgery between the dates of 6/10/2016 and 4/10/2017 at John Hunter Hospital. Computed tomography was utilized to calculate the psoas area at the L3 spinal level. Pre‐operative blood samples were obtained for C1q analysis and de Morton Mobility Index (DEMMI) was also performed. Results: A total of 51 patients were included in the study. The median age of the patients were 69 years old. We did not demonstrate a correlation between serum C1q and DEMMI scores with psoas area. Conclusion: Our findings suggest that neither C1q nor DEMMI scores are correlated with psoas area in a colorectal cancer population. [ABSTRACT FROM AUTHOR]

Background: Preoperative skin antiseptics are used prior to surgery to reduce the risk of surgical site infection (SSI). There is debate as to which is the most effective. The aim of this network meta‐analysis (NMA) is to compare the effectiveness of different skin preparations at reducing SSIs in patients undergoing incisional surgery. Methods: The study protocol was published in PROSPERO (CRD4202181599) a priori with predefined search terms and inclusion/exclusion criteria. The skin preparations for comparison were: chlorhexidine/alcohol (CHA), chlorhexidine/water (CHW), poviodine/alcohol (PVIA), poviodine/water (PVIW). The records identified were screened by two authors independently by title, abstract and in full text. The revised tool for risk‐of bias (ROB2) assessment was used. Results: Twenty‐nine RCTs involving 15 796 patients were included in the NMA. A significant but small increase in the odds of infection was seen in the PVIW group compared to the CHA group (OR 1.34, 95%CrI 1.09–1.64), but other comparisons were not statistically significantly different. Ranking the treatment arms showed there was a 64% probability that CHA is the most effective and a 62.7% probability that PVIW is the least effective treatment. Conclusion: Chlorhexidine/alcohol (CHA) was found to be the most effective for prevention of superficial and deep SSI while PVIW was the least. There was no differences seen between CHA and PVIA, or CHW and PVIW. The superiority of CHA is likely due to the effect of the alcohol in the base. Hence the choice between CHA and PVIA should be based on health and cost considerations. [ABSTRACT FROM AUTHOR]

The author presents his response to the special article "Meeting the Responsibility of Professionalism," published in the August 8/22, 2011 issue which to him was a subject of quality performance. He cites his definition of professionalism for a physician which means placing the interests of the patient ahead of his own interests including financial interests. He notes the lack of enthusiasm by medical professional organizations in supporting cost-cutting measures that will affect their income.

The virtual patient is a case-based computer program that combines textual information with multimedia elements such as audio, graphics, and animation. It is increasingly being utilized as a teaching modality by medical educators in various fields of instruction. The inherent complexity of older patients and the shortage of geriatrics educators have spurred the development of virtual patient programs to teach geriatrics at the medical undergraduate, graduate, and postgraduate levels. As an instructional tool, the Virtual Patient must be placed in the correct educational context to help educators identify opportunities for its proper use in the curriculum. In this review, the experiences of three medical schools in the development and application of geriatric virtual patients are described as case studies. In each case study, the challenges encountered and solutions developed are presented. Areas of future research in the use of virtual patients in geriatrics education include the determination of the optimal combination of features, the settings of use of virtual patient programs, the underlying pedagogy, and the limitations in its application in clinical instruction. [ABSTRACT FROM AUTHOR]

Purpose: Natural Killer (NK) cells are a vital part of immune surveillance and have been implicated in colorectal cancer development and prognosis. This systematic review aims to distil the literature on NK cells as it relates to colorectal cancer. Methods: All published studies over 10 years relating to NK cells and colorectal cancer were reviewed. All studies publishing in English, searchable via pubmed or through reference review and reporting directly on the nature or function of NK cells in colorectal cancer patients were included. Outcomes were determined as alterations or new information regarding NK cells in colorectal cancer patients. Results: Natural killer cells may be implicated in the development of colorectal cancer and may play a role in prognostication of the disease. NK cells are altered by the treatment (both surgical and medical) of colorectal cancer and it seems likely that they will also be a target for manipulation to improve colorectal cancer survival. Conclusions: NK cell morphology and function are significantly affected by the development of colorectal cancer. Observation of NK cell changes may lead to earlier detection and better prognostication in colorectal cancer. Further study is needed into immunological manipulation of NK cells which may lead to improved colorectal cancer survival. [ABSTRACT FROM AUTHOR]

Anastomotic leak rates have not improved over several decades despite improvements in surgical techniques and patient care. The gut microbiome has been implicated in the development of leaks. The exact mechanisms by which tissue oxygenation affects gut microbial composition and anastomotic healing physiology are unclear. Also, commonly used carbon dioxide (CO 2) is a known vasodilator that improves tissue oxygen tension. We performed a systematic review to determine the influence of hyperoxia, hypoxia, and hypercapnia on the gut microbiome and anastomotic healing. A literature search was performed in MEDLINE, EMBASE, and COCHRANE to identify studies investigating the effects of hyperoxia, hypoxia, and hypercapnia on anastomotic healing and gut microbiota published between 1998 and 2018. Two reviewers screened the articles for eligibility and quality. Fifty-three articles underwent full text review, and a narrative synthesis was undertaken. Hyperoxia is associated with better anastomotic healing, increased gastrointestinal oxygen tension, and may reduce gut anaerobes. Hypoxia is associated with poor healing and increased gut anaerobes. However, it is unclear if hypoxia is the most important predictor of anastomotic leaks. Low pressure CO 2 pneumoperitoneum and mild systemic hypercapnia are both associated with increased gastrointestinal oxygen tension and may improve anastomotic healing. We found no studies which investigated the effect of hypercapnia on gut microbiota in the context of anastomotic healing. Tissue oxygenation influences gut anastomotic healing, but little evidence exists to demonstrate the influence on the gut microbiome in the context of healing. Further studies are needed to determine if anastomotic microbiome changes with altered tissue oxygenation and if this affects healing and leak rates. If confirmed, altering tissue oxygenation through hyperoxia or hypercapnia could be feasible means of altering the microbiome such that anastomotic leak rates reduce. [ABSTRACT FROM AUTHOR]

Open burning is a widely practiced method of solid waste disposal in many regions of the world and represents a significant source of air pollution. Black carbon (BC) is a particularly serious air pollutant emitted from the uncontrolled burning of waste in open fires because it has a global warming potential (GWP) up to 5000 times greater than carbon dioxide (CO 2) and is also linked to detrimental health impacts. However, few quantitative measurements of BC from open burning have been completed to establish the extent and impacts of this emission source on the environment. Emission factors (EFs) for BC from burning mixed solid waste samples were measured in the laboratory based on waste compositions in a representative developing country (Mexico). Black carbon EFs were also derived for individual waste types, including: green waste, different types of plastics, textiles and paper and cardboard. Individual waste BC EFs were combined using waste composition data from different areas of the world to estimate regional and global BC emissions from this source. The results demonstrated that BC emissions from open burning of waste have a significant climate impact, equivalent to 2–10% of global CO 2 Eq emissions. Global BC CO 2 Eq emissions from burning waste are 2–8 times larger compared to methane (CH 4) CO 2 Eq emissions arising from the decomposition of equivalent amounts of combustible biodegradable waste disposed at dumpsites. Action to reduce open burning of waste would have a significant and immediate benefit to improving air quality and reducing the potential impact on climate change. • BC EFs were measured for single and mixed waste streams. • BC EFs were in the range of 0.02–53.1 g kg−1, depending strongly on waste type. • BC emissions from open burning of waste were calculated for different regions. • BC emissions from burning waste contributes over 2–10% of global CO 2 Eq emissions. • BC CO 2 Eq from burning is 4 times larger compared to CH 4 from waste decomposition. [ABSTRACT FROM AUTHOR]

Background: Post‐operative length of stay (LOS) is an increasingly important clinical indicator in general surgery. Despite this, no tool has been validated to predict LOS or readiness for discharge in general surgical patients. The de Morton Mobility Index (DEMMI) is a functional mobility assessment tool that has been validated in rehabilitation patient populations. In this prospective cohort study, we aimed to identify if trends in DEMMI scores were associated with discharge within 1 week and overall LOS in general surgical patients. Methods: A total of 161 patients who underwent elective gastrointestinal resections were included. DEMMI scores were performed preoperatively, on days 1, 2, 3 and 30 post‐operative. Statistical analysis was performed to identify any association between DEMMI scores and discharge within 1 week and LOS. Results: Functional recovery (measured by achieving 80% of baseline DEMMI score by post‐operative day 1) was significantly associated with discharge within 1 week. Presence of a stoma was associated with longer LOS. The area under the receiver operating characteristic curve using functional recovery on post‐operative day 1 as a predictor of discharge within 1 week is 0.772. Conclusion: The DEMMI score is a fast, easy and useful tool to, on post‐operative day 1, predict discharge within 1 week. The utility of this is to act as an anticipatory trigger for more proactive and efficient discharge planning in the early post‐operative period, and there is potential to use the DEMMI as a comparator in clinical trials to assess functional recovery. [ABSTRACT FROM AUTHOR]

The inactivation of Cryptosporidium species oocysts during sewage sludge treatment is important to protect human health when the residual biosolids are applied to agricultural land. Quantifying the decay of Cryptosporidium species during sludge treatment for microbiological assurance purposes is difficult if low numbers are present in wastewater. The rate of decay of Cryptosporidium parvum oocysts during solar/air drying treatment and in sludge stockpiles in temperate environment conditions was simulated in laboratory inoculation experiments using sludge sampled from a mesophilic anaerobic digester. Oocyst numbers were also determined in settled lagoon sludge samples collected from three operational rural wastewater treatment plants (WWTPs). C. parvum oocysts were enumerated by immunomagnetic separation followed by staining with vital dyes and examination by confocal laser scanning microscopy. An air-drying/storage period equivalent to 11 weeks was required for a 1 log10 reduction of viable oocysts inoculated into digested sludge. Oocyst viability in air-dried and stored digested sludge decreased with time, but was independent of sludge desiccation and dry solids (DS) content. No oocysts were detected in sludge samples collected from the anaerobic digester, and the average concentration of oocysts found in settled lagoon sludge from the rural WWTP was 4.6 × 102 oocysts/g DS. [ABSTRACT FROM AUTHOR]

International controls for biosolids application to agricultural land ensure the protection of human health and the environment, that it is performed in accordance with good agricultural practice and that nitrogen (N) inputs do not exceed crop requirements. Data from the scientific literature on the total, mineral and mineralizable N contents of biosolids applied to agricultural land under a wide range of climatic and experimental conditions were collated. The mean concentrations of total N (TN) in the dry solids (DS) of different biosolids types ranged from 1.5% (air-dried lime-treated (LT) biosolids) to 7.5% (liquid mesophilic anaerobic digestion (LMAD) biosolids). The overall mean values of mineralizable N, as a proportion of the organic N content, were 47% for aerobic digestion (AeD) biosolids, 40% for thermally dried (TD) biosolids, 34% for LT biosolids, 30% for mesophilic anaerobic digestion (MAD) biosolids, and 7% for composted (Com) biosolids. Biosolids air-dried or stored for extended periods had smaller total and mineralizable N values compared to mechanically dewatered types. For example, for biosolids treated by MAD, the mean TN (% DS) and mineralizable N (% organic N) contents of air-dried materials were 3% and 20%, respectively, compared to 5% and 30% with mechanical dewatering. Thus, mineralizable N declined with the extent of biological stabilization during sewage sludge treatment; nevertheless, overall plant available N (PAN = readily available inorganic N plus mineralizable N) was broadly consistent across several major biosolids categories within climatic regions. However, mineralizable N often varied significantly between climatic regions for similar biosolids types, influencing the overall PAN. This may be partly attributed to the increased rate, and also the greater extent of soil microbial mineralization of more stable, residual organic N fractions in biosolids applied to soil in warmer climatic zones, which also raised the overall PAN, compared to cooler temperate areas. It is also probably influenced by differences in upstream wastewater treatment processes that affect the balance of primary and secondary, biological sludges in the final combined sludge output from wastewater treatment, as well as the relative effectiveness of sludge stabilization treatments at specific sites. Better characterization of biosolids used in N release and mineralization investigations is therefore necessary to improve comparison of system conditions. Furthermore, the review suggested that some international fertilizer recommendations may underestimate mineralizable N in biosolids, and the N fertilizer value. Consequently, greater inputs of supplementary mineral fertilizer N may be supplied than are required for crop production, potentially increasing the risk of fertilizer N emissions to the environment. Thus greater economic and environmental savings in mineral N fertilizer application are potentially possible than are currently realized from biosolids recycling programmes. [ABSTRACT FROM AUTHOR]

Factors affecting the decay of Salmonella Birkenhead and coliphage, as representatives of bacterial and viral pathogens, respectively, during mesophilic anaerobic digestion (MAD) and air drying treatment of anaerobically digested sewage sludge were investigated. Controlled concentrations of S. Birkenhead were inoculated into non-sterile, autoclaved, γ-irradiated and nutrient-supplemented sludge and cultures were incubated at 37 °C (MAD sludge treatment temperature) or 20 °C (summer air drying sludge treatment temperature). Nutrient limitation caused by microbial competition was the principal mechanism responsible for the decay of S. Birkenhead by MAD and during air drying of digested sludge. The effects of protease activity in sludge on MS2 coliphage decay in digested and air dried sludge were also investigated. MS2 coliphage showed a 3.0-3.5 log10 reduction during incubation with sludge-protease extracts at 37 °C for 25 h. Proteases produced by indigenous microbes in sludge potentially increase coliphage inactivation and may therefore have a significant role in the decay of enteric viruses in sewage sludge. The results help to explain the loss of viability of enteric bacteria and viral pathogens with treatment process time and contribute to fundamental understanding of the various biotic inactivation mechanisms operating in sludge treatment processes at mesophilic and ambient temperatures. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the Live/Dead BacLight viability kit as a method for enumerating viable eggs of Ascaris suum in sewage sludge as a surrogate for the human roundworm. The number and viability status of eggs of A. suum were accurately measured directly in sewage sludge samples by the BacLight method, compared to the conventional incubation-microscopy procedure. BacLight stains were not toxic to A. suum eggs, in contrast to some conventional vital dyes which disrupted viable eggs. The method was effective for the direct examination of eggs in heavily contaminated samples or seeded sludge containing ∼200 eggs/g DS in sludge with 5% DS content. However, a recovery method would be necessary to examine samples with small numbers of eggs, for instance in sludge from regions where the prevalence of infection with Ascaris lumbricoides is low. The BacLight technique may therefore be an effective alternative to conventional incubation-microscopy for enumerating Ascaris eggs in contaminated field samples or to validate sludge treatment processes by examining decay rates of inoculated A. suum eggs in laboratory simulations. Most field samples would require recovery from an appropriate number of composite samples prior to vital staining. [ABSTRACT FROM AUTHOR]

Focal segmental glomerulosclerosis (FSGS) is a histological lesion with many causes, including inherited genetic defects, with significant proteinuria being the predominant clinical finding at presentation. Mutations in COL4A3 and COL4A4 are known to cause Alport syndrome (AS), thin basement membrane nephropathy, and to result in pathognomonic glomerular basement membrane (GBM) findings. Secondary FSGS is known to develop in classic AS at later stages of the disease. Here, we present seven families with rare or novel variants in COL4A3 or COL4A4 (six with single and one with two heterozygous variants) from a cohort of 70 families with a diagnosis of hereditary FSGS. The predominant clinical finding at diagnosis was proteinuria associated with hematuria. In all seven families, there were individuals with nephrotic-range proteinuria with histologic features of FSGS by light microscopy. In one family, electron microscopy showed thin GBM, but four other families had variable findings inconsistent with classical Alport nephritis. There was no recurrence of disease after kidney transplantation. Families with COL4A3 and COL4A4 variants that segregated with disease represent 10% of our cohort. Thus, COL4A3 and COL4A4 variants should be considered in the interpretation of next-generation sequencing data from such patients. Furthermore, this study illustrates the power of molecular genetic diagnostics in the clarification of renal phenotypes. [ABSTRACT FROM AUTHOR]

BK polyomavirus ( BKV) infection continues to be a significant source of allograft dysfunction in kidney transplant recipients. The optimal screening method to detect BKV remains undetermined. In this retrospective analysis of 347 consecutive kidney transplant recipients, we compare the diagnostic and screening performance of urine electron microscopy ( EM) with plasma polymerase chain reaction ( PCR) in testing for BKV, using biopsy-proved polyomavirus-associated nephropathy ( PVAN) as the gold standard. Sixty-nine of 347 recipients had a positive screening test for BKV infection. Twenty-nine patients underwent biopsy, and 11 were diagnosed with PVAN. Sensitivity rates of urine EM and plasma PCR were 88% and 100%, respectively. Specificity rates of urine EM and plasma PCR were 91% and 78%. There was no statistical difference in the operating characteristics of the two tests. The majority of both plasma PCR and urine EM tests were positive in the six months prior to a diagnostic biopsy confirming PVAN. In those patients who had evidence of BKV infection but did not have PVAN, the percentage of positive screening tests decreased with aggressive lowering of immunosuppression. We conclude that urine EM and plasma PCR both function well in screening for BKV infection and in the diagnosis of PVAN. There is an opportunity to detect viral replication, lower immunosuppression, and to prevent PVAN in this population. [ABSTRACT FROM AUTHOR]