Communication-constrained distributed quantile regression with optimal statistical guarantees

We address the problem of how to achieve optimal inference in distributed quantile regression without stringent scaling conditions. This is challenging due to the non-smooth nature of the quantile regression (QR) loss function, which invalidates the use of existing methodology. The difficulties are resolved through a double-smoothing approach that is applied to the local (at each data source) and global objective functions. Despite the reliance on a delicate combination of local and global smoothing parameters, the quantile regression model is fully parametric, thereby facilitating interpretation. In the low-dimensional regime, we establish a finite-sample theoretical framework for the sequentially defined distributed QR estimators. This reveals a trade-off between the communication cost and statistical error. We further discuss and compare several alternative confidence set constructions, based on inversion of Wald and score-type tests and resampling techniques, detailing an improvement that is effective for more extreme quantile coefficients. In high dimensions, a sparse framework is adopted, where the proposed doubly-smoothed objective function is complemented with an ℓ1-penalty. We show that the corresponding distributed penalized QR estimator achieves the global convergence rate after a near-constant number of communication rounds. A thorough simulation study further elucidates our findings

Cellular cholesterol transport proteins in diabetic nephropathy

published_or_final_versio

Control of a bidirectional single-phase grid interface for electric vehicles

The number of electric vehicles is expected to increase exponentially in the next decade. This represents a huge potential for grid support, such as energy storage in their batteries, with advantages for grid operators and for customers. For this purpose, flexible power interfaces are required. This paper presents a simulation of a bidirectional singlephase power interface between an electric vehicle battery and the grid. The proposed system is fully simulated and counts with features such as vehicle-to-grid, vehicle-to-home and grid-to-vehicle. All power flow and the controllers for these modes of operation are described in detail. The simulation was developed in a Software-in-the-Loop scheme to facilitate a future physical implementation with a Hardware-in-the-Loop platform. The proposed system was extensively tested via simulation, the results proving the system is stable, able to change operation modes smoothly and definition of the exchanged active and reactive powers.info:eu-repo/semantics/publishedVersio

A case of triple pathology: seronegative anti-glomerular basement membrane antibody-mediated glomerulonephritis and membranous nephropathy in a patient with underlying diabetic kidney disease

In diabetic patients with acute kidney injury (AKI), kidney biopsy often reveals non-diabetic kidney pathology. This case describes a patient with known Type 1 diabetes who presented with AKI, nephrotic syndrome and haematuria. Combination pathology of seronegative anti-glomerular basement membrane antibody-mediated glomerulonephritis (anti-GBM GN), membranous nephropathy (MN) and diabetic nephropathy (DN) was demonstrated. Strong linear GBM IgG-staining on biopsy with crescentic GN and clinical AKI led to a diagnosis of anti-GBM GN, although serum antibodies were not detectable. Features of DN, Kimmelstiel–Wilson nodules and albumin staining were also present, along with features of MN, such as subepithelial deposits on electron microscopy. Despite treatment with immunosuppression and plasmapheresis, there was no recovery of kidney function. Coexisting anti-GBM GN and MN is well recognized, but the concurrent diagnosis with DN has not been described

Nutrition Profile of Products with Cartoon Animations on the Packaging: A UK Cross-Sectional Survey of Foods and Drinks.

BACKGROUND: Marketing, including the use of cartoon animations on packaging, has been shown to influence the food children choose to eat. This paper aims to determine the nutritional quality of UK food and drink products featuring child-friendly characters on pack. METHODS: A comprehensive cross-sectional survey of food and drink with packaging appealing to children available in the UK. Products were classified high in fat, salt and/or sugar (HFSS) according to the UK nutrient profiling model and guidance for front of pack nutrition labelling. Logistic regression was used to determine whether there was a significant relationship between nutritional quality of products, and animation type. RESULTS: Over half (51%) of 532 products with animations on packaging were classified as HFSS. Food products featuring unlicensed characters were significantly more likely to be deemed HFSS than those with licensed characters, according to both the nutrient profiling model (odds ratio (OR) 2.1, 95% CI: 1.3 to 3.4) and front of pack nutrition labelling system (OR 2.3, 95% confidence interval CI: 1.4 to 3.7). CONCLUSIONS: The use of cartoon characters on HFSS products is widespread. Policies to restrict the use of such marketing tactics should be considered to prevent children being targeted with unhealthy foods and drinks

Transient intraluminal diverticulum of the esophagus: A significant flow artifact

Esophagography in 12 patients showed a characteristic oval-to oblong-shaped barium collection surrounded by a thin radiolucent margin. The collection closely resembled an intraluminal diverticulum. Twelve patients demonstrated these findings, 6 on single-contrast and 6 on double-contrast examinations. These findings were not reproducible on repeat barium swallows, and endoscopy failed to demonstrate an intraluminal diverticulum. Nine of the patients underwent esophagectomy and esophageal substitution. Pathologic examination of the gross specimen did not reveal evidence of intraluminal diverticula. The association of this radiologic appearance in patients with moderately severe motility disorder of the esophagus is emphasized.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48158/1/261_2005_Article_BF01887813.pd

Swimming using surface acoustic waves

Microactuation of free standing objects in fluids is currently dominated by the rotary propeller, giving rise to a range of potential applications in the military, aeronautic and biomedical fields. Previously, surface acoustic waves (SAWs) have been shown to be of increasing interest in the field of microfluidics, where the refraction of a SAW into a drop of fluid creates a convective flow, a phenomenon generally known as SAW streaming. We now show how SAWs, generated at microelectronic devices, can be used as an efficient method of propulsion actuated by localised fluid streaming. The direction of the force arising from such streaming is optimal when the devices are maintained at the Rayleigh angle. The technique provides propulsion without any moving parts, and, due to the inherent design of the SAW transducer, enables simple control of the direction of travel

Association of proinflammatory cytokines and chemotherapy-associated cognitive impairment in breast cancer patients: a multi-centered, prospective, cohort study.

BackgroundExisting evidence suggests that proinflammatory cytokines play an intermediary role in postchemotherapy cognitive impairment. This is one of the largest multicentered, cohort studies conducted in Singapore to evaluate the prevalence and proinflammatory biomarkers associated with cognitive impairment in breast cancer patients.Patients and methodsChemotherapy-receiving breast cancer patients (stages I-III) were recruited. Proinflammatory plasma cytokines concentrations [interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, granulocyte-macrophage colony-stimulating factor, interferon-γ and tumor necrosis factor-α] were evaluated at 3 time points (before chemotherapy, 6 and 12 weeks after chemotherapy initiation). The FACT-Cog (version 3) was utilized to evaluate patients' self-perceived cognitive disturbances and a computerized neuropsychological assessment (Headminder) was administered to evaluate patients' memory, attention, response speed and processing speed. Changes of cognition throughout chemotherapy treatment were compared against the baseline. Linear mixed-effects models were applied to test the relationships of clinical variables and cytokine concentrations on self-perceived cognitive disturbances and each objective cognitive domain.ResultsNinety-nine patients were included (age 50.5 ± 8.4 years; 81.8% Chinese; mean duration of education = 10.8 ± 3.3 years). Higher plasma IL-1β was associated with poorer response speed performance (estimate: -0.78; 95% confidence interval (CI) -1.34 to -0.03; P = 0.023), and a higher concentration of IL-4 was associated with better response speed performance (P = 0.022). Higher concentrations of IL-1β and IL-6 were associated with more severe self-perceived cognitive disturbances (P = 0.018 and 0.001, respectively). Patients with higher concentrations of IL-4 also reported less severe cognitive disturbances (P = 0.022).ConclusionsWhile elevated concentrations of IL-6 and IL-1β were observed in patients with poorer response speed performance and perceived cognitive disturbances, IL-4 may be protective against chemotherapy-associated cognitive impairment. This study is important because cytokines would potentially be mechanistic mediators of chemotherapy-associated cognitive changes

Morgagni hernia repair in children over two decades: Institutional experience, systematic review, and meta-analysis of 296 patients

BACKGROUND/PURPOSE: Morgagni diaphragmatic hernia (MH) is rare. We report our experience based on routine patch use in MH repair to curb recurrence. A systematic review and meta-analysis were performed to study the recurrence and complications associated with minimally invasive surgery and the use of patch. METHODS: We retrospectively reviewed all cases of MH who underwent first-time repair in 2012-2017 in our institution to determine recurrence and complication rate. A MEDLINE search related to minimally invasive surgery (MIS) and patch repair of MH was conducted for systematic review. Eligible articles published from 1997-2017 with follow-up data available were included. Primary outcomes measured were recurrence and complication. Meta-analysis to compare open versus MIS and primary versus patch repair in the MIS group were performed in comparative cohorts. Continuous data were presented as median (range), and statistical significance was P<0.05. RESULTS: In our institution, 12 consecutive patients aged 17-month-old (22 days-7 years), underwent laparoscopic patch repair of MH, with one conversion to laparotomy. No recurrence or significant complication occurred over a follow-up period of 8 months (1-48 months). Thirty-six articles were included from literature review and were combined with the current series. All were retrospective case reports or series, of which 6 were comparative cohorts with both MIS and open repairs. A total of 296 patients from 37 series were ultimately used for analysis: 80 had open repair (4 patch) and 216 had MIS repair (32 patch), with a patch rate of 12%. There were 13 recurrences (4%): no difference between open and MIS repairs (4/80 vs 9/216, p=0.75); recurrence rate following primary repair was 13/260 (5%), but no recurrence occurred with 36 patch repairs. Meta-analysis showed no difference in recurrence between open and MIS repair (p=0.83), whereas patch repair was associated with 14% less recurrence compared with primary repair, although it did not reach statistical significance (p=0.12). There were 13 complications (5%): no difference between open and MIS repairs (5/80 vs 8/216, p=0.35). One small bowel obstruction occurred in a patient who had laparoscopic patch repair. CONCLUSION: In MH, recurrence and complication rates are comparable between MIS and open repairs. Use of patch appeared to confer additional benefit in reducing recurrence. TYPE OF STUDY: Systematic review LEVEL OF EVIDENCE: 3A

Reformulation and Priorities for Reducing Energy Density; Results from a Cross-Sectional Survey on Fat Content in Pre-Packed Cakes and Biscuits Sold in British Supermarkets

Cakes and biscuits contribute to energy, total and saturated fat and sugar in British diets. So far, the UK government has prompted manufacturers to reduce energy density in these products through a reduction of their sugar content. We conducted a cross-sectional survey of the fat content of cakes and biscuits available in nine UK supermarket chains. In cakes (n = 381), the mean total fat content was 17.9 &#177; 5.2 g/100 g (39% of the overall energy); range (1.4&#8722;35.6 g/100 g) and the average saturated fat content in cakes was 5.9 &#177; 3.4 g/100 g (13% of the overall energy); range (0.3&#8722;20 g/100 g). In biscuits (n = 481), the mean total fat content was 21.8 g &#177; 6.3 g/100 g (40% of the overall energy); range (0.7&#8722;38.9 g/100 g) and the average saturated fat content was 11.4 &#177; 4.9 g/100 g (23% of the overall energy); range (0.3&#8722;22.3 g/100 g). In both cakes and biscuits, total and saturated fat content was positively correlated with energy density. Our results show that cakes and biscuits sold in UK supermarkets are high in total and saturated fat, and that fat content contributes substantially to product energy density. Fat reformulation in these products would effectively reduce energy density, calorie intake and help prevent obesity. Fat reformulation should be implemented simultaneously with sugar reformulation and be focused on saturated fat, as this will have the additional effect of lowering LDL cholesterol