The efficiency, timeliness, health outcomes and cost-effectiveness of a new aeromedical retrieval model in Central Australia: A pre- and post-implementation observational study.

OBJECTIVE: To assess timeliness, efficiency, health outcomes and cost-effectiveness of the 2018 redesigned Central Australian aeromedical retrieval model. DESIGN: Pre- and postimplementation observational study of all patients receiving telehealth consultations from remote medical practitioners (RMPs) or Medical Retrieval and Consultation Centre (MRaCC) physicians between 1/1/2015 and 29/2/2020. Descriptive and inferential statistics measuring system efficiency, timeliness, health outcomes and incremental cost-effectiveness. FINDINGS: There were 9%-10% reductions in rates of total aeromedical retrievals, emergency department admissions and hospitalisations postimplementation, all p-values < 0.001. Usage rates for total hospital bed days and ICU hours were 17% lower (both p < 0.001). After adjusting for periodicity (12% fewer retrievals on weekends), each postimplementation year, there were 0.7 fewer retrievals/day (p = 0.002). The mean time from initial consultation to aeromedical departure declined by 18 minutes post-implementation (115 vs. 97 min, p = 0.007). The hazard of death within 365 days was nonsignificant (0.912, 95% CI 0.743-1.120). Postimplementation, it cost $302 more per hospital admission and $3051 more per year of life saved, with a 75% probability of cost-effectiveness. These costs excluded estimated savings of $744,528/year in reduced hospitalisations and the substantial social and out-of-pocket costs to patients and their families associated with temporary relocation to Alice Springs. CONCLUSION: Central Australia's new critical care consultant-led aeromedical retrieval model is more efficient, is dispatched faster and is more cost-effective. These findings are highly relevant to other remote regions in Australia and internationally that have comparable GP-led retrieval services.

Evaluation of a new medical retrieval and primary health care advice model in Central Australia: Results of pre- and post-implementation surveys.

INTRODUCTION: In February 2018 the Remote Medical Practitioner (RMP)-led telehealth model for providing both primary care advice and aeromedical retrievals in Central Australia was replaced by the Medical Retrieval and Consultation Centre (MRaCC) and Remote Outreach Consultation Centre (ROCC). In this new model, specialists with advanced critical care skills provide telehealth consultations for emergencies 24/7 and afterhours primary care advice (MRaCC) while RMPs (general practitioners) provide primary care telehealth advice in business hours via the separate ROCC. OBJECTIVE: To evaluate changes in clinicians' perceptions of efficiency and timeliness of the new (MRaCC) and (ROCC) model in Central Australia. DESIGN: There were 103 and 72 respondents, respectively, to pre- and post-implementation surveys of remote clinicians and specialist staff. FINDINGS: Both emergency and primary care aspects of telehealth support were perceived as being significantly more timely and efficient under the newly introduced MRaCC/ROCC model. Importantly, health professionals in remote community were more likely to feel that their access to clinical support during emergencies was consistent and immediately available. DISCUSSION: Respondents consistently perceived the new MRaCC/ROCC model more favourably than the previous RMP-led model, suggesting that there are benefits to having separate referral streams for telehealth advice for primary health care and emergencies, and staffing the emergency stream with specialists with advanced critical care skills. CONCLUSION: Given the paucity of literature about optimal models for providing pre-hospital medical care to remote residents, the findings have substantial local, national and international relevance and implications, particularly in similar geographically large countries, with low population density.

Sickle cell disease patients in two London trusts: Genotyping including RH variants.

BACKGROUND: All SCD patients need extended RBC antigen typing (by serology or genotyping) for provision of extended RH, K matched blood and to guide RBC selection in those with complex transfusion requirements. Genotyping can also identify RH variants which can cause sensitisation even when extended RH phenotypically matched blood is provided and alloantibodies associated with RH variants can cause HTRs. OBJECTIVES: To review the use of RBC genotyping in SCD patients at two London trusts (ICHNT, LNWH) with a focus on RH variants. METHODS: Retrospective review with data collected from clinical notes, local and national pathology reporting systems. RESULTS: A 311/482 (64%) ICHNT patients and 181/346 (52%) LNWH patients had extended genotyping. Of genotyped patients, 68 (22%) ICHNT and 31 (17%) LNWH patients had RH variants. Eight ICHNT patients had RH variants and corresponding antibodies associated with RH variants; 4/8 received multiple transfusions with antigen positive RBCs but had no evidence of haemolysis. One LNWH patient had a RH variant with corresponding alloantibody but could not be investigated further for possible HTR. CONCLUSIONS: Most patients (59%) had genotyping and a significant number had RH variants (99, 20%). A small proportion (9, 9%) had antibodies associated with RH variants, but with no evidence of clinically significant HTRs despite transfusions in four of them with antigen positive RBCs. All SCD patients should have RBC genotyping including RH variants (preferentially over extended phenotyping) to guide better selection of RBC units. However, where antigen negative blood cannot be provided, the risk of alloimmunisation is not inevitable and subsequent HTRs from antibodies associated with RH variants might not always occur.

Evaluating the medical direct costs associated with prematurity during the initial hospitalization in Rwanda: a prevalence based cost of illness study.

BACKGROUND: Prematurity is still the leading cause of global neonatal mortality, Rwanda included, even though advanced medical technology has improved survival. Initial hospitalization of premature babies (PBs) is associated with high costs which have an impact on Rwanda's health budget. In Rwanda, these costs are not known, while knowing them would allow better planning, hence the purpose and motivation for this research. METHODS: This was a prospective cost of illness study using a prevalence approach conducted in 5 hospitals (University Teaching Hospital of Butare, Gisenyi, Masaka, Muhima, and Ruhengeri). It included PBs admitted from June to July 2021 followed up prospectively to determine the medical direct costs (MDC) by enumerating the cost of all inputs. Descriptive analyses and ordinary least squares regression were used to illustrate factors associated with and predictive of mean cost. The significance level was set at p < 0.05. RESULTS: A total of 123 PBs were included. Very preterm and moderate PBs were 36.6% and 23.6% respectively and the average birth weight (BW) was 1724 g (SD: 408.1 g). The overall mean MDC was $237.7 per PB (SD: $294.9) representing 28% of Gross Domestic Product (GDP) per capita per year. Costs per PB varied with weight category, prematurity degree, hospital level, and length of stay (LoS) among other variables. MDC was dominated by drugs and supplies (65%) with oxygen being an influential driver of MDC accounting for 38.4% of total MDC. Birth weight, oxygen therapy, and hospital level were significant MDC predictive factors. CONCLUSION: This study provides an in-depth understanding of MDC of initial hospitalization of PBs in Rwanda. It also indicates predictive factors, including birth weight, which can be managed through measures to prevent or delay preterm birth. IMPLICATION FOR PREMATURITY PREVENTION AND MANAGEMENT: The results suggest a need to revise the benefits and entitlements of insured people to include drugs and interventions not covered that are essential and where there are no alternatives. Having oxygen plants in hospitals may reduce oxygen-related costs. Furthermore, interventions to reduce prematurity should be evaluated using cost-effectiveness analysis since its overall burden is high.

Appearance of peanut agglutinin in the blood circulation after peanut ingestion promotes endothelial secretion of metastasis-promoting cytokines.

Peanut agglutinin (PNA) is a carbohydrate-binding protein in peanuts that accounts for ~0.15% peanut weight. PNA is highly resistant to cooking and digestion and is rapidly detectable in the blood after peanut consumption. Our previous studies have shown that circulating PNA mimics the actions of endogenous galactoside-binding protein galectin-3 by interaction with tumour cell-associated MUC1 and promotes circulating tumour cell metastatic spreading. The present study shows that circulating PNA interacts with micro- as well as macro-vascular endothelial cells and induces endothelial secretion of cytokines MCP-1 (CCL2) and IL-6 in vitro and in vivo. The increased secretion of these cytokines autocrinely/paracrinely enhances the expression of endothelial cell surface adhesion molecules including integrins, VCAM and selectin, leading to increased tumour cell-endothelial adhesion and endothelial tubule formation. Binding of PNA to endothelial surface MCAM (CD146), via N-linked glycans, and subsequent activation of PI3K-AKT-PREAS40 signalling is here shown responsible for PNA-induced secretion of MCP-1 and IL-6 by vascular endothelium. Thus, in addition to its influence on promoting tumour cell spreading by interaction with tumour cell-associated MUC1, circulating PNA might also influence metastasis by enhancing the secretion of metastasis-promoting MCP-1 and IL-6 from the vascular endothelium.

Gastric metastasis before diagnosis of primary invasive lobular breast carcinoma: a rare case presentation from Pakistan.

Metastatic spread of invasive lobular breast carcinoma to stomach is rare especially before diagnosis of primary breast cancer. Incorrect diagnosis might result in delay of appropriate treatment for breast cancer. Recognition of this possibility enables better clinical management. A 62-year-old female presented with upper gastrointestinal symptoms and weight loss and was referred to a gastroenterologist for investigation. At the time of initial diagnosis of stomach cancer, patient was asymptomatic for breast cancer. Multiple gastric biopsies taken showed features suspicious of metastatic breast cancer. Consequently, the initial provisional diagnosis of stomach cancer changed into metastatic invasive lobular breast carcinoma. These findings were corroborated radiologically. The patient was treated with letrozole and zoledronic acid as first-line therapy for one year. Residual metastatic breast cancer was present in the gastric mucosa. The patient was treated with endocrine therapy containing ribociclib and treatment was ineffective confirmed by PET-CT scan. But her symptoms have resolved completely despite her presentation with stage IV. We present rare case of initial presentation of gastric metastasis before diagnosis of a primary invasive lobular breast carcinoma. Correct diagnosis and appropriate treatment were accomplished through initial clinical suspicion, accurate histological examination, and endoscopy together with analysis of disease-specific biomarkers.

Long-Term Iron Deficiency and Dietary Iron Excess Exacerbate Acute Dextran Sodium Sulphate-Induced Colitis and Are Associated with Significant Dysbiosis.

BACKGROUND: Oral iron supplementation causes gastrointestinal side effects. Short-term alterations in dietary iron exacerbate inflammation and alter the gut microbiota, in murine models of colitis. Patients typically take supplements for months. We investigated the impact of long-term changes in dietary iron on colitis and the microbiome in mice. METHODS: We fed mice chow containing differing levels of iron, reflecting deficient (100 ppm), normal (200 ppm), and supplemented (400 ppm) intake for up to 9 weeks, both in absence and presence of dextran sodium sulphate (DSS)-induced chronic colitis. We also induced acute colitis in mice taking these diets for 8 weeks. Impact was assessed (i) clinically and histologically, and (ii) by sequencing the V4 region of 16S rRNA. RESULTS: In mice with long-term changes, the iron-deficient diet was associated with greater weight loss and histological inflammation in the acute colitis model. Chronic colitis was not influenced by altering dietary iron however there was a change in the microbiome in DSS-treated mice consuming 100 ppm and 400 ppm iron diets, and control mice consuming the 400 ppm iron diet. Proteobacteria levels increased significantly, and Bacteroidetes levels decreased, in the 400 ppm iron DSS group at day-63 compared to baseline. CONCLUSIONS: Long-term dietary iron alterations affect gut microbiota signatures but do not exacerbate chronic colitis, however acute colitis is exacerbated by such dietary changes. More work is needed to understand the impact of iron supplementation on IBD. The change in the microbiome, in patients with colitis, may arise from the increased luminal iron and not simply from colitis.

Prepectoral Dual-Port Tissue Expander Placement: Can This Eliminate Suction Drain Use?

OBJECTIVES: The most common method of performing breast reconstruction after a mastectomy is using tissue expanders. Significant drainage that can lead to seromas and possible infection is a common sequela after mastectomies, and therefore, closed suction drains are routinely placed during the initial surgery (Vardanian et al. Plast Reconstr Surg. 2011;128:403-410). Drains, however, are associated with increased pain and discomfort for the patient and have been attributed to an increased infection rate by some authors (Degnim et al. Ann Surg. 2013;258:240-247; Saratzis et al. Clin Breast Cancer. 2009;9:243-246). We report on our experience using a dual-chamber tissue expander placed in the prepectoral space without acellular dermal matrix or other supportive material, which allows for drainage of periprosthetic fluid and avoids drain placement. PATIENTS AND METHODS: A retrospective, single-institution review of patients' records was performed for all patients who underwent prepectoral tissue expander placement between January 2018 and June 2019. Patients who had drains placed or who underwent autologous reconstruction in combination with expander placement were excluded. Thirty-nine patients were selected, with a total of 66 expander placements. Demographics including body mass index, comorbidities, history of smoking or steroid use, perioperative chemotherapy and radiation therapy, and intraoperative details and indications for surgery were retrospectively collected. Outcomes were separated into minor and major complications. Major complications were defined as complications that required surgical intervention. RESULTS: There were 51 prepectoral reconstructions with a dual-chamber tissue expander and no further surgical drain and 15 reconstructions using a standard expander with an additional closed suction drain. Overall complications for the no-drain cohort were 13.7% compared with 20% in the drain cohort (P = 0.68). Surgical site infection rate is 7.84% in the no-drain cohort compared with 13.3% in the drain cohort (P = 0.61). Mean numeric postoperative pain score at 6 hours was 3.2 in the no-drain cohort compared with 4.3 in the drain cohort (P = 0.03) and 4.17 compared with 5.6 at 12 hours, respectively (P = 0.04). Mean time to exchange of implant in the no-drain cohort was 152 days versus 126 days in the drain cohort (P = 0.38). Median follow-up times were 157 days for the no-drain cohort and 347 days for the drain cohort. CONCLUSIONS: Immediate breast reconstruction using a dual-chamber tissue expander offers a drain-free alternative to the immediate implant-based breast reconstruction. Our infection rate with 7.8% is lower than our own reported rates with subpectoral tissue expander reconstruction using either acellular dermal matrix or poly-4-hydroxybutyrate (17% and 11%). The overall complication rate is similar to historic data associated with breast reconstruction after mastectomy and suggests that dual-chamber expander placement offers a safe alternative possibly decreasing the patient's postoperative pain and discomfort that often is associated with closed suction drains (Saratzis et al. Clin Breast Cancer. 2009;9:243-246).

Cockayne syndrome group A and B proteins converge on transcription-linked resolution of non-B DNA.

Cockayne syndrome is a neurodegenerative accelerated aging disorder caused by mutations in the CSA or CSB genes. Although the pathogenesis of Cockayne syndrome has remained elusive, recent work implicates mitochondrial dysfunction in the disease progression. Here, we present evidence that loss of CSA or CSB in a neuroblastoma cell line converges on mitochondrial dysfunction caused by defects in ribosomal DNA transcription and activation of the DNA damage sensor poly-ADP ribose polymerase 1 (PARP1). Indeed, inhibition of ribosomal DNA transcription leads to mitochondrial dysfunction in a number of cell lines. Furthermore, machine-learning algorithms predict that diseases with defects in ribosomal DNA (rDNA) transcription have mitochondrial dysfunction, and, accordingly, this is found when factors involved in rDNA transcription are knocked down. Mechanistically, loss of CSA or CSB leads to polymerase stalling at non-B DNA in a neuroblastoma cell line, in particular at G-quadruplex structures, and recombinant CSB can melt G-quadruplex structures. Indeed, stabilization of G-quadruplex structures activates PARP1 and leads to accelerated aging in Caenorhabditis elegans In conclusion, this work supports a role for impaired ribosomal DNA transcription in Cockayne syndrome and suggests that transcription-coupled resolution of secondary structures may be a mechanism to repress spurious activation of a DNA damage response.

Promoting Social Connection and Deepening Relations Among Older Adults: Design and Qualitative Evaluation of Media Parcels.

BACKGROUND: Being socially connected is related to well-being, and one way of avoiding social isolation is to deepen existing relationships. Even though existing relationships can be reinforced by regular and meaningful communication, state-of-the-art communication technologies alone do not increase the quality of social connections. Thus, there is a need for the involvement of a trained human facilitator in a network of older adults, preferably for a short period, to promote the deepening of their relationships. OBJECTIVE: This study aimed to evaluate the hypothesis that a human-facilitated, media-sharing social networking system can improve social connection in a small group of older people, who are more vulnerable to social isolation than most, and deepen their relationships over a period of a few weeks. METHODS: We conducted the design and evaluation of Media Parcels, a novel human-facilitated social networking system. Media Parcels is based on the metaphor of a facilitator collecting and delivering parcels in the physical mail. Extending the metaphor, the system supports a facilitator in designing time-based dialogue requesting parcels from participants that bring out their memories and feelings, in collecting the parcels, wrapping them in annotations that communicate the corresponding requests, and delivering the wrapped parcel to a target person. Qualitative evaluation was carried out in two trials with a group of three people each, one with family members (children and father; aged 55, 56, and 82 years old) and the other with a group of friends (aged 72, 72, and 74 years old), over two weeks. In each trial, data were collected in three interviews (pre-, mid-, and posttrial) and via system logging. RESULTS: Collected data indicate positive social effects for deepening and developing relationships. The parcel metaphor was easily understood and the computational system was readily adopted. Preferences with regard to media production or consumption varied among participants. In the family group, children preferred receiving media parcels (because of their sentimental value) to producing them, whereas the father enjoyed both. In the friendship group, preferences varied: one friend enjoyed both producing and receiving, while the other two preferred one over the other. In general, participants reported a preference for the production of items of a certain type depending on the associated content. Apart from having a strong engagement with the system, participants reported feeling closer to each other than usual. CONCLUSIONS: For both groups, Media Parcels was effective in promoting media sharing and social connections, resulting in the deepening of existing relationships. Its design informs researchers who are attempting to promote social connection in older adults.

Brönsted Catalyzed Hydrolysis of Microcystin-LR by Siderite.

Six naturally occurring minerals were employed to catalyze the hydrolysis of microcystin-LR (MC-LR) in water. After preliminary screening experiments, siderite stood out among these minerals due to its higher activity and selectivity. In comparison with kaolinite, which is known to act as a Lewis acid catalyst, siderite was found to act primarily as a Brönsted acid catalyst in the hydrolysis of MC-LR. More interestingly, we found that the presence of humic acid significantly inhibited catalytic efficiency of kaolinite, while the efficiency of siderite remained high (∼98%). Reaction intermediates detected by LC-ESI/MS were used to indicate cleavage points in the macrocyclic ring of MC-LR, and XPS was used to characterize siderite interaction with MC-LR. Detailed analysis of the in situ ATR-FTIR absorption spectra of MC-LR indicated hydrogen bonding at the siderite-water-MC-LR interface. A metastable ring, involving hydrogen bonding, between surface bicarbonate of siderite and an amide of MC-LR was proposed to explain the higher activity and selectivity toward MC-LR. Furthermore, siderite was found to reduce the toxicity of MC-LR to mice by hydrolyzing MC-LR peptide bonds. The study demonstrates the potential of siderite, an earth-abundant and biocompatible mineral, for removing MC-LR from water.

A Rapid Diagnostic for Detection of Aphelenchoides besseyi and A. fujianensis Based on Real-Time PCR.

Aphelenchoides besseyi and A. fujianensis have been frequently found in mixed populations associated with forage grass seed in Brazil. The morphological similarity between both species has previously led A. fujianensis to be erroneously identified as A. besseyi. A. besseyi is a quarantine pest in many countries that import Brazilian forage seed; however, there is no current evidence suggesting that A. fujianensis is a plant-parasitic species. Two real-time polymerase chain reaction (qPCR) diagnostics were developed to detect each species and an operational envelope was established. A set of primers and hydrolysis probes for each species was designed targeting the large subunit (LSU) region. To assess their specificity, primers and probes sets were tested with samples of nontarget Aphelenchoides and Paraphelenchus sp. also frequently associated with forage seed. Experiments using dilutions of purified plasmid standards underpinned the sensitivity of the qPCR assays, which detected as few as 10 copies of target nematode ribosomal DNA. Thus, the developed diagnostics were sufficiently sensitive to detect DNA extracted from a fragment of a single target nematode. There was a positive correlation between copy number of the target species and nematode abundance, suggesting the potential of this method for quantification. Evidence of intra-individual variability among cloned sequences of the LSU region in a single A. besseyi population is also reported.

A novel thermal compression device for perioperative warming: a randomized trial for feasibility and efficacy.

BACKGROUND: Inadvertent perioperative hypothermia (IPH) leads to surgical complications and increases length of stay. IPH rates are high with the current standard of care, forced air warming (FAW). Our hypothesis is that a prototype thermal compression device that heats the popliteal fossa and soles of the feet, with lower leg compression, increases perioperative temperatures and reduces IPH compared to the current standard of care. METHODS: Thirty six female breast surgery patients, at a tertiary academic hospital, were randomized to the device or intraoperative FAW (stage I) with a further 18 patients randomized to the device with a single heating area only (stage II, popliteal fossa or sole of the feet). Stage I: 37 patients recruited (final 36). Stage II: 18 patients recruited (final 18). INCLUSION CRITERIA: general anesthesia with esophageal monitoring for over 30 min, legs available and able to fit the device and no contraindications to leg heating or compression. The intervention was: Stage I: Investigational prototype thermal compression device (full device group) or intraoperative FAW. Stage II: Device with only a single heating location. Primary outcomes were perioperative temperatures and incidence of IPH. Secondary outcomes were local skin temperature, general and thermal comfort scores and presence of perioperative complications, including blood loss. RESULTS: Mean temperatures in the full device group were significantly higher than the FAW group in the pre-operative (36.7 vs 36.4 °C, p < 0.001), early intraoperative (36.3 vs 35.9 °C, p < 0.001), intraoperative (36.6 vs 36.2 °C, p < 0.001) and postoperative periods (36.8 vs 36.5 °C, p < 0.001). The incidence of IPH in the device group was also significantly lower (16.7% vs 72.0%, p = 0.001). Thermal comfort scores were significantly higher in the full device group and hypothermia associated wound complications were higher in the FAW group. CONCLUSIONS: The thermal compression device is feasible and has efficacy over the FAW. Further studies are recommended to investigate clinically significant outcomes. TRIAL REGISTRATION: clinicaltrials.gov ( NCT02155400 ).

Development and Application of Ultra-Performance Liquid Chromatography-TOF MS for Precision Large Scale Urinary Metabolic Phenotyping.

To better understand the molecular mechanisms underpinning physiological variation in human populations, metabolic phenotyping approaches are increasingly being applied to studies involving hundreds and thousands of biofluid samples. Hyphenated ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) has become a fundamental tool for this purpose. However, the seemingly inevitable need to analyze large studies in multiple analytical batches for UPLC-MS analysis poses a challenge to data quality which has been recognized in the field. Herein, we describe in detail a fit-for-purpose UPLC-MS platform, method set, and sample analysis workflow, capable of sustained analysis on an industrial scale and allowing batch-free operation for large studies. Using complementary reversed-phase chromatography (RPC) and hydrophilic interaction liquid chromatography (HILIC) together with high resolution orthogonal acceleration time-of-flight mass spectrometry (oaTOF-MS), exceptional measurement precision is exemplified with independent epidemiological sample sets of approximately 650 and 1000 participant samples. Evaluation of molecular reference targets in repeated injections of pooled quality control (QC) samples distributed throughout each experiment demonstrates a mean retention time relative standard deviation (RSD) of <0.3% across all assays in both studies and a mean peak area RSD of <15% in the raw data. To more globally assess the quality of the profiling data, untargeted feature extraction was performed followed by data filtration according to feature intensity response to QC sample dilution. Analysis of the remaining features within the repeated QC sample measurements demonstrated median peak area RSD values of <20% for the RPC assays and <25% for the HILIC assays. These values represent the quality of the raw data, as no normalization or feature-specific intensity correction was applied. While the data in each experiment was acquired in a single continuous batch, instances of minor time-dependent intensity drift were observed, highlighting the utility of data correction techniques despite reducing the dependency on them for generating high quality data. These results demonstrate that the platform and methodology presented herein is fit-for-use in large scale metabolic phenotyping studies, challenging the assertion that such screening is inherently limited by batch effects. Details of the pipeline used to generate high quality raw data and mitigate the need for batch correction are provided.

The Effect of Hydrodynamic Slip on Membrane-Based Salinity-Gradient-Driven Energy Harvesting.

The effect of hydrodynamic slip on salinity-gradient-driven power conversion by the process of reverse electrodialysis, in which the free energy of mixing of salt and fresh water across a nanoporous membrane is harnessed to drive an electric current in an external circuit, is investigated theoretically using a continuum fluid dynamics model. A general one-dimensional model is derived that decouples transport inside the membrane pores from the effects of electrical resistance at the pore ends, from which an analytical expression for the power conversion rate is obtained for a perfectly ion-selective membrane as a function of the slip length, surface charge density, membrane thickness, pore radius, and other membrane and electrolyte properties. The theoretical model agrees quantitatively with finite-element numerical calculations and predicts significant enhancements--up to several times--of salinity-gradient power conversion due to hydrodynamic slip for realistic systems.

Automated Functional Imaging by 2D Speckle Tracking Echocardiography Reveals High Incidence of Abnormal Longitudinal Strain in a Cohort of Pediatric Oncology Patients.

BACKGROUND: Automated functional imaging (AFI) was introduced to two-dimensional speckle-tracking echocardiography to facilitate strain assessment in the clinical settings. In patients treated with cardiotoxic anthracyclines, AFI may be helpful in the detection of early myocardial injury when left ventricular ejection fraction (LVEF) remains normal. METHODS: We retrospectively assessed feasibility of AFI in 143 echocardiograms on 102 subjects aged 0.4-22 years (mean 12.3) obtained over a 12-month period. We computed a Z-score for apical four-chamber longitudinal strain using published normal data to assess for abnormal strain in patients with and without previous exposure to anthracyclines. RESULTS: AFI was feasible in 95.1% of echocardiograms, with low inter- and intraobserver variability. There was a statistically significant association between abnormal longitudinal strain Z-score (SZ < -2.0) and depressed LVEF (<55%, P < 0.001). However, 46% of echocardiograms with normal LVEF had abnormal SZ; half of which had no prior anthracycline exposure. The correlation between SZ and LVEF was strongest in subjects exposed to anthracyclines (r(2) = 0.12, P < 0.01). Increasing age was associated with decreasing SZ. Total cumulative dose, after adjusting for age, was inversely associated with SZ (r(2) = 0.42, P < 0.001). Time from last dose of anthracycline had no significant association with SZ. CONCLUSIONS: AFI is highly feasible in the clinical settings. The observed high prevalence of abnormal longitudinal strain in our cohort emphasizes the importance of obtaining baseline measurements prior to anthracycline treatment. The effects of anthracycline on longitudinal strain may be dose and age dependent, with younger children less likely to show abnormalities.

Illinois River Nitrate-Nitrogen Concentrations and Loads: Long-term Variation and Association with Watershed Nitrogen Inputs.

The Illinois River is a major contributor of nitrate-N to the Mississippi River and the Gulf of Mexico, where nitrate is a leading cause of summertime benthic hypoxia. Corn-soybean production on tile-drained land is a leading source of nitrate-N in this river system, in addition to municipal wastewater discharge. We calculated annual nitrate-N loads in the Illinois River at Valley City from 1976 to 2014 by linear interpolation. Although there was not a significant trend in annual loads during the entire study period, there was a significant downward trend in flow-weighted nitrate-N concentration after 1990 despite high concentrations in 2013 after the 2012 drought. Multivariate regression analysis revealed a statistically significant association between annual flow-weighted nitrate-N concentration and cumulative residual agricultural N inputs to the watershed during a 6-yr window. This suggests that declines in flow-weighted nitrate-N concentration may reflect increasing N use efficiency in agriculture and a depletion of legacy N stored in the watershed. The watershed appears to have transitioned from a state of stationarity in nitrate concentration to nonstationarity. The average annual nitrate-N load at Valley City from 2010 to 2014 was 10% less than the 1980-1996 average load, indicating recent progress toward Illinois' nutrient loss reduction milestone of 15% reduction by 2025 and ultimate target of 45% reduction.

Riverine Response of Sulfate to Declining Atmospheric Sulfur Deposition in Agricultural Watersheds.

Sulfur received extensive study as an input to terrestrial ecosystems from acidic deposition during the 1980s. With declining S deposition inputs across the eastern United States, there have been many studies evaluating ecosystem response, with the exception of agricultural watersheds. We used long-term (22 and 18 yr) sulfate concentration data from two rivers and recent (6 yr) data from a third river to better understand cycling and transport of S in agricultural, tile-drained watersheds. Sulfate concentrations and yields steadily declined in the Embarras (from ∼10 to 6 mg S L) and Kaskaskia rivers (from 7 to 3.5 mg S L) during the sampling period, with an overall -23.1 and -12.8 kg S ha yr balance for the two watersheds. There was evidence of deep groundwater inputs of sulfate in the Salt Fork watershed, with a much smaller input to the Embarras and none to the Kaskaskia. Tiles in the watersheds had low sulfate concentrations (<10 mg S L), similar to the Kaskaskia River, unless the field had received some form of S fertilizer. A multiple regression model of runoff (cm) and S deposition explained much of the variation in Embarras River sulfate ( = 0.86 and 0.80 for concentrations and yields; = 46). Although atmospheric deposition was much less than outputs (grain harvest + stream export of sulfate), riverine transport of sulfate reflected the decline in inputs. Watershed S balances suggest a small annual depletion of soil organic S pools, and S fertilization will likely be needed at some future date to maintain crop yields.

Chloride Sources and Losses in Two Tile-Drained Agricultural Watersheds.

Chloride is a relatively unreactive plant nutrient that has long been used as a biogeochemical tracer but also can be a pollutant causing aquatic biology impacts when concentrations are high, typically from rock salt applications used for deicing roads. Chloride inputs to watersheds are most often from atmospheric deposition, road salt, or agricultural fertilizer, although studies on agricultural watersheds with large fertilizer inputs are few. We used long-term (21 and 17 yr) chloride water quality data in two rivers of east-central Illinois to better understand chloride biogeochemistry in two agricultural watersheds (Embarras and Kaskaskia), the former with a larger urban land use and both with extensive tile drainage. During our sampling period, the average chloride concentration was 23.7 and 20.9 mg L in the Embarras and Kaskaskia Rivers, respectively. Annual fluxes of chloride were 72.5 and 61.2 kg ha yr in the Embarras and Kaskaskia watersheds, respectively. In both watersheds, fertilizer chloride was the dominant input (∼49 kg ha yr), with road salt likely the other major source (23.2 and 7.2 kg ha yr for the Embarras and Kaskaskia watersheds, respectively). Combining our monitoring data with earlier published data on the Embarras River showed an increase in chloride concentrations as potash use increased in Illinois during the 1960s and 1970s with a lag of about 2 to 6 yr to changes in potash inputs based on a multiple-regression model. In these agricultural watersheds, riverine chloride responds relatively quickly to potash fertilization as a result of tile-drainage.

Temperature and Substrate Control Woodchip Bioreactor Performance in Reducing Tile Nitrate Loads in East-Central Illinois.

Tile drainage is the major source of nitrate in the upper Midwest, and end-of-tile removal techniques such as wood chip bioreactors have been installed that allow current farming practices to continue, with nitrate removed through denitrification. There have been few multiyear studies of bioreactors examining controls on nitrate removal rates. We evaluated the nitrate removal performance of two wood chip bioreactors during the first 3 yr of operation and examined the major factors that regulated nitrate removal. Bioreactor 2 was subject to river flooding, and performance was not assessed. Bioreactor 1 had average monthly nitrate removal rates of 23 to 44 g N m d in Year 1, which decreased to 1.2 to 11 g N m d in Years 2 and 3. The greater N removal rates in Year 1 and early in Year 2 were likely due to highly degradable C in the woodchips. Only late in Year 2 and in Year 3 was there a strong temperature response in the nitrate removal rate. Less than 1% of the nitrate removed was emitted as NO. Due to large tile inputs of nitrate (729-2127 kg N) at high concentrations (∼30 mg nitrate N L) in Years 2 and 3, overall removal efficiency was low (3 and 7% in Years 2 and 3, respectively). Based on a process-based bioreactor performance model, Bioreactor 1 would have needed to be 9 times as large as the current system to remove 50% of the nitrate load from this 20-ha field.