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Objective To better understand why children born with cloacal anomalies are at a high risk of renal insufficiency, this study aims to determine baseline renal volume in children with cloacal anomalies compared to controls. We hypothesized children with cloacal anomalies would be born with less renal volume. Methods An IRB approved database of children with cloacal anomalies was reviewed. Controls were female patients with two-vessel umbilical cord or preauricular tags who underwent screening renal ultrasound. Children were included if they had a renal ultrasound in the first 3 months of life. Cloacal exstrophy, horseshoe and cross-fused ectopic kidneys were excluded. Total and individual kidney volumes were compared between the two groups. Results The study cohort consisted of 109 patients, 46 (42.2%) cloaca patients and 63 (57.8%) controls. In unadjusted analyses, average total renal volume for cloaca and control patients was 22.4 cm3 versus 25.5 cm3 respectively (p=0.1006), and there was no significant difference when adjusting for age (p=0.3915). The estimated difference in renal unit volume between cloaca patients without solitary kidneys and controls was -1.6 cm3 (95% C.I.: -3.6, 0.4; p=0.1201), and there was no significant difference when adjusting for age (p=0.4725). The age-adjusted difference in renal unit volume between cloaca patients with solitary kidney and controls was 1.8 cm3 (95% CI: -1.1, 4.8; p=0.2148). Conclusions Children with cloacal anomalies have similar baseline renal volumes as children without cloacal anomalies. Therefore, the increased risk of renal insufficiency in this patient population appears to be due to renal injury post-natally.

Microbial exopolysaccharides (EPSs) exhibit diverse functionalities and offer a variety of structural options that can be altered to fit a specific purpose. EPSs can degrade within the body via biological processes, and polysaccharides are regarded as generally safe. More so, microbial EPS is replicable from several known, inexpensive, and plentiful sources. Drug delivery-related research involving polysaccharides have continuously cited minimal to zero cytotoxicity and, where tested, sufficient drug release and a competent release profile. Transdermal drug delivery systems as films not only avoids first-pass metabolism, but also provides pain-free administration, assists patients with dysphagia, has increased patient compliance, can be self-administered, and can be removed at any time. Commonly used synthetic polymers in the field of drug delivery have been related to problems regarding toxicity and immunogenicity, escalating the need for an alternative. Ultimately, the risks while using synthetic polymers could result in serious negative influences involving physiological, physiochemical, and molecular events. Research involving exopolysaccharides from extremophiles is only recently gaining attention. However, commercial use of microbial polysaccharides in other areas as well as the positive results from preliminary research suggests microbial EPSs have a promising future in biomedical engineering and medicine, especially as an alternative to current synthetic polymers.

Power generated by PV panels is highly vulnerable to uncertain weather conditions, and impedance connected to its terminals. Therefore, to maximize the energy productivity from panels by controlling output impedance, a power electronic converter capable of adopting maximum power point tracking (MPPT) technique is required. This paper includes a comprehensive review of basic and advanced MPPT techniques proposed to address the variations in temperature, irradiance, partial shading conditions. Power processing equipment such as dc/dc converters and inverters are mandatory in extracting power from PV panels and utilizing either for standalone systems or grid integration. Grid integration is a major focus where access to utility line ranging from domestic micro-inverters ( MW). A centralized inverter topology interfaces a MW power rating PV farm consisting several parallel strings of series connected PV panels to the grid. This review article contributes on presenting an overview of the state-of-the-art power electronics systems for integration of PV panels to the grid. Various interfacing power electronic architectures covering micro-inverter, central inverter up to modular inverter approach operating at low switching frequency and high switching frequency with resonant and pulse-width modulated (PWM) soft-switching or hard-switching are reported. Various voltage-fed and current-fed multi-level inverters for such architectures are studied and discussed.

A rigid-walled semi-infinite circular cylindrical waveguide enclosing a weakly nonlinear fluid is considered. A quadratic nonlinear interaction is assumed as a model. A flat rigid piston generates an axisymmetric harmonic pressure that is prescribed as the input at the finite end of the waveguide. The objective is to study the modal interactions of waves. A regular perturbation method is used to separate the linear (primary) and the quasilinear (second harmonic) equations. First, linear solutions are established. Their quasilinear interactions then lead to modal interactions. Typically, the linear wavenumbers at the quasilinear order generate homogenous wavenumbers. Intersections of both these wavenumbers in the wavenumber-frequency plane are considered as resonances since the resulting pressure grows in amplitude in the axial propagating direction. The conditions under which the solutions become resonant or non-resonant are presented. In this last case, a beating phenomenon occurs with distance. It is found that the resonances are rare, except for the plane wave. Generally, the forced linear wavenumbers and the quasilinear generated wavenumbers acquire numerical values close to each other and create the beating phenomenon. (C) 2019 Elsevier Ltd. All rights reserved.

Mitochondrial dysfunction has been implicated in the pathogenesis of primary open-angle glaucoma (POAG). However, the potential significance of mitochondrial DNA (mtDNA) haplogroups to POAG has not been evaluated in the overaffected African American population. To investigate the association of mtDNA haplogroups with POAG and its phenotypic characteristics, genotyping data from 4081 African American subjects (1919 cases and 2162 controls) was analyzed using 1293 positions on mtDNA. The overall frequency of mtDNA haplogroups in the Primary Open-Angle African American Glaucoma Genetics (POAAGG) study cohort was 37% L3, 29% L2, 21% L1, 4% L0, and 10% non-African haplogroups (non-L). When all haplogroups (L0, L1, L2, and non-L) were compared against theL3 reference group, after adjusting by age and principal component of ancestry, the non-L3 haplogroups showed higher risk of POAG (OR-1.19, p = 0.02), with a particularly strong association among males (OR = 1.41, p = 0.003). More specifically the non-L group was associated with higher POAG risk than the L3 haplogroup (OR = 1.77, p = 0.007, Bonferroni adjusted p = 0.027) and to the L3e (n = 256, OR = 1.92, p = 0.007, Bonferroni adjusted p = 0.029). No significant association was found when genders were analyzed together or in female only analysis. There were no significant differences in various POAG endophenotypes across mtDNA haplogroups. This study expands our knowledge of mitochondrial genetics and mtDNA haplogroup associations in African American POAG. Further work is needed to better understand the functional role of mtDNA polymorphisms and their interactions with nuclear genes that affect POAG.

This paper focuses on identifying crash risk factors associated with injury severity of teen drivers. Crash data obtained from the Highway Safety and Information System (HSIS) for the entire state of North Carolina, for years 2011 to 2013, was used for analysis and modeling. Among all the crashes during the study period, a total of 62,990 crashes involving teen drivers (15 to 19 years) were analyzed. A partial proportionality odds model was developed to identify factors contributing to injury severity of teen drivers. The results obtained indicate that teen drivers driving sports utility vehicles and pickup trucks are more likely to be severely injured when compared to teen drivers driving passenger cars. Teen drivers are more likely to be severely injured on weekdays, particularly during peak hours. The chances of teen drivers getting involved in severe injury crashes on Tuesdays and Fridays is higher when compared to Sundays. Age, gender, road configuration, terrain, adverse weather condition, and access control are observed to have a significant effect on teen driver's injury severity. Keywords: Teen drivers, Crash, Injury severity, Contributing factor, Partial proportionality odds model

A fully coupled formulation is presented for sound radiation from a finite flexible perforated panel set in an infinite rigid unperforated baffle. The panel is excited by a point harmonic force and radiates sound into the acoustic medium on both sides of the baffle. Prior to coupling with the fluid, the change in the inertial and stiffness properties of the panel due to perforations and their effect on the in vacuo natural frequencies and mode shapes are accounted for using the receptance method. The coupled acoustic and structural equations are formulated using the 2-D wavenumber transforms. Since the formulation is in terms of the panel velocity, a certain square root singularity that typically appears in the denominator is avoided. The self- and inter-modal coupling coefficients are evaluated either analytically or numerically. The radiated power, panel mean quadratic velocity and radiation efficiency plots are obtained for different perforation ratios for both center and off-center excitations. At first, our formulation is validated against an unperforated case using a study available in the literature. Next, for our perforated panel case, we assume that both the half-spaces are filled with the acoustic fluid. It is observed that the radiation efficiency decreases with the increase in the perforation ratio, irrespective of the surrounding acoustic medium. However, for the water-loaded panel, the radiation efficiency is found to be lower than when the panel is immersed in air. It is found that for a light fluid like air, a one-way coupled formulation is adequate. The natural frequencies of a water-loaded perforated panel are also presented. It is found that for a given mode, the natural frequency increases with increase in the perforation ratio, (C) 2018 Elsevier B.V. All rights reserved.

Single coronary artery (SCA) is a rare anomaly with an incidence of 0.01%–0.004% in general population. We present a rare case of SCA, which is L1 subtype of Lipton's classification of SCA, and accounts for only 0.016% of the population undergoing coronary angiogram. The patient presented with acute inferior myocardial infarction, on further evaluation she was found to have SCA. The right coronary artery was arising as a branch from the proximal left anterior descending artery (LAD) with distal LAD continuing as posterior descending artery and posterior left ventricular branch, and with a critical stenosis in left circumflex artery and LAD. She underwent successful multivessel angioplasty with good results.

Cicatrix formation, which can form after neonatal circumcision to entrap the glans penis, presents a therapeutic challenge. Previous studies in the literature have described either using a topical steroid cream or stretching of the scar tissue with an instrument but not a combination of both modalities. In our experience, monotherapy has resulted in significant recurrence and/or need for further treatment. We present our successful experience that combines cicatrix stretching with a hemostat using local anesthesia in the office followed by several weeks of topical steroids with a minority of patients needing any additional therapy.

LewisX (LeX) is a branched trisaccharide Galβ1→4(Fucα1→3)GlcNAc that is expressed on many cell surface glycoproteins and plays critical roles in innate and adaptive immune responses. However, efficient synthesis of glycopeptides bearing LeX remains a major limitation for structure-function studies of the LeX determinant. Here we report a total synthesis of a LeX pentasaccharide 1 using a regioselective 1-benzenesulfinyl piperidine/triflic anhydride promoted [3 + 2] glycosylation. The presence of an Fmoc-threonine amino acid facilitates incorporation of the pentasaccharide in solid phase peptide synthesis, providing a route to diverse O-linked LeX glycopeptides. The described approach is broadly applicable to the synthesis of a variety of complex glycopeptides containing O-linked LeX or sialyl LewisX (sLeX).

Modal interactions are studied in a weakly nonlinear structural-acoustic waveguide with a cylindrical geometry. The infinite cylindrical waveguide is driven by a flat piston at the center. Standard nonlinear equations are used for the shell and the fluid. The perturbation method separates the nonlinear equations into a linear set and a nonlinear set. At the linear order, only propagating modes are included. Due to the flat nature of the piston, these modes are axisymmetric. These linear order modes interact due to the nonlinearity and generate higher order modes. When a certain inverse relation between phase speeds gets satisfied, spatial resonance (weak shock) occurs, i.e., the solution grows in the propagation direction. Along the same lines, when this matching does not occur, the solution acquires a spatial beating nature that oscillates along the propagation direction. The responses, i.e., resonances or beats are further categorized as self-mode and cross-mode interactions. The conditions and the closed form solutions for resonances and beats are derived. Further, the effect of the boundary flexibility on the said resonances and beats is also presented. And it is seen that the nonlinear wave propagation is significantly different between a rigid and a flexible waveguide.