Age-related changes in innervation in hypertrophic pyloric stenosis

BACKGROUND/PURPOSE: Recent reports have identified abnormal innervation of the circular muscle layer involving the fine intramuscular nerve fibers in hypertrophic pyloric stenous (HPS). HPS presenting after 3 months of age is rare. The aim of this study was to determine the distribution pattern of nerve fibers in the smooth muscle layers in HPS and correlate this with age at presentation. METHODS: Full-thickness pyloric muscle biopsy specimens were obtained from eight patients with HPS (five age 3 to 5 weeks, two age 3 months, and one age 7 months) and five controls with normal pylorus (age 5 days to 3 years). All specimens were stained with monoclonal antibody to the neural cell adhesion molecule (NCAM) using immunohistochemistry. RESULTS: There were many NCAM-positive nerve fibers in the circular and longitudinal muscle layers in the controls. No NCAM positive nerve fibers were seen in the circular or longitudinal muscle layers in the five cases of HPS in which the patients were less than 5 weeks old. In the two cases in which the patients were 3 months old, occasional NCAM-positive nerve fibers were seen in the circular layer, and moderate numbers of NCAM positive fibers were seen in the longitudinal muscle layers. Moderate numbers of NCAM-positive nerve fibers in the circular muscle layer and many NCAM positive nerve fibers in the longitudinal muscle layers were identified in the 7-month-old HPS patient. CONCLUSIONS: The data suggest that the pyloric muscle lacks innervation in the young HPS infant. Whereas, at 3 months of age the hypertrophied pyloric muscle is partially innervated, and at 7 months of age the pyloric muscle has practically normal innervation.     

Powder Deposition in Three Parallel-Oriented Dies of Different Shapes

Uniformity of bulk density distribution during the die filling process is required to minimize quality problems, such as distortion and cracking, for powder compacts. Understanding the die filling process is necessary in ensuring a uniform powder deposition. The second-generation pressure deposition tester (PDT-II) was used to investigate the deposition process and final pressure distribution of powder filling in toroidal, cylindrical, and E-shaped dies. All tests were conducted using a spray-dried free-flowing granular powder. The results indicated that for toroidal dies: (1) the area around 0° orientation (the leeward end) had the highest pressure values (1186.7 to 2498.0 Pa), with the average pressure values of the remaining area 353.7-648.0 Pa; (2) the pressure distribution was symmetrical about the centerline parallel to the feed shoe movement direction; (3) the highest feed shoe speed (500 mm/s) led to the most nonuniform pressure distribution among the three speeds; (4) higher feed shoe speed did not always result in higher final pressure values; and (5) the right die tended to have higher final pressure values (215.0 to 2498.0 Pa) than the center die (95.4 to 2052.5 Pa). For E-shaped dies: (1) the final pressure values of the middle leg (308.9 to 760.7 Pa) were higher than those of the left and the right legs (148.9 to 530.3 Pa); (2) the area along the backside had the highest final pressure value (1054.6 to 1303.8 Pa); (3) the pressure distribution was symmetrical about the centerline parallel to the feed shoe movement direction; and (4) neither the center die nor the right die always had higher pressure values than the other one at all locations. Comparison between cylindrical and toroidal dies indicated that: (1) neither of the two die shapes (cylinder and toroid) led to consistently higher or lower final pressure values at all locations and (2) for all three feed shoe speeds, the toroidal die had higher average final pressure values in the 0° orientation.     

Detection of West Nile virus by the polymerase chain reaction and analysis of nucleotide sequence variation

A polymerase chain reaction (PCR) assay was developed to rapidly detect and identify West Nile (WN) virus. The RNA from seven isolates of WN virus from six countries and four other flaviviruses (Kunjin, Japanese encephalitis, St. Louis encephalitis, and yellow fever viruses) was reverse-transcribed (RT) and amplified by PCR. The nucleotide sequences of the amplified products were determined by a rapid, automated DNA sequencing method. The WN virus RT/PCR assay detected the target gene segment of sequencing method. The WN virus RT/PCR assay detected the target gene segment of isolates from both the African-Middle Eastern group and the Indian group with a sensitivity of approximately 0.05 pg of viral RNA. Kunjin virus was the only other flavivirus tested that produced a band of the appropriate size. Five of seven WN virus isolates showed 92-98% homology in the nucleotide sequence of their PCR products. The sequence of one isolate was virtually identical to the published sequence of the Nigerian isolate (99.5% homology). No correlation was established between the degree of nucleotide homology, geographic location, time of isolation, or source of the isolates.     

Serum enzyme abnormalities in protein energy malnutrition

A semi-quantitative right coronary artery score (RCA score) was derived from the ratio of the number of the major left ventricular branches of the right coronary artery to the total of the right coronary and left circumflex arteries, to stratify the extent of perfusion in patients with right coronary artery dominance. Thirty-seven patients with one-vessel coronary disease involving a dominant right coronary artery proximal to the left ventricular branches were selected for study. Thallium scintigraphy was performed after right intracoronary injection in 11 patients, and 26 patients underwent conventional stress thallium scintigraphy (24 exercise thallium and two dipyridamole thallium scintigraphy). Thallium scores of perfusion region size after right intracoronary thallium injection and perfusion defect size in stress thallium studies were quantitated from planar thallium images. Both the RCA score and the regional thallium scores spanned over a wide range. The RCA score (range 0.23-0.85) correlated best with the posterior (70 degrees left anterior oblique view) plus lateral segment (40 degrees left anterior oblique view) thallium score (r = 0.88 and 0.53 for intracoronary and stress thallium studies respectively). It also correlated with the summed thallium scores in the posterior, lateral, apical and inferior segments (r = 0.73 and 0.54 respectively) but not with thallium scores in the apex or inferior segment alone. The proposed RCA score quantitates the variable posterolateral perfusion territory of the right coronary artery, and could stratify the area of myocardium at risk from coronary stenosis in the majority of patients with right coronary dominance.     

A STUDY OF EXPERIMENTAL DESIGN OPTIMALITY FOR WIENER SYSTEMS

In the context of nonlinear dynamic system identification for Hammerstein systems, Rollins et al. (2003a) studied the information efficiency of the following two competing experimental design approaches: statistical design of experiments (SDOE) and pseudo-random sequences design (PRSD). The focus of this study is the Wiener system and evaluates SDOE against PRS under D-optimal efficiency. Three cases are evaluated and the results strongly support SDOE as the better approach.     

An analysis and optimisation of the geometrical inaccuracy due to wire lag phenomenon in WEDM

An extensive study of the wire lag phenomenon in Wire-cut Electrical Discharge Machining (WEDM) has been carried out and the trend of variation of the geometrical inaccuracy caused due to wire lag with various machine control parameters has been established in this paper. In an extremely complicated machining process like Wire-cut EDM, which is governed by as many as ten control factors, it is very difficult to select the best parametric combination for a particular situation arising out of customer requirements. In the present research study, all the machine control parameters are considered simultaneously for the machining operation which comprised a rough cut followed by a trim cut. The objective of the study has been to carry out an experimental investigation based on the Taguchi method involving thirteen control factors with three levels for an orthogonal array L₂₇ (3¹³). The main influencing factors are determined for given machining criteria, such as: average cutting speed, surface finish characteristic and geometrical inaccuracy caused due to wire lag. Also, the optimum parametric settings for different machining situations have been found out and reported in the paper.     

A Workflow Scheduling Method for Cloud Computing Platform

Wireless Personal Communications - Scheduling in computing environments such as homogeneous and heterogonous is very challenging and faces various difficulties computationally. This computing needs...     

Experimental investigations in powder mixed electric discharge machining of Ti–35Nb–7Ta–5Zrβ-titanium alloy

The present research is the first type of study in which the application of powder mixed electrical discharge machining (PMEDM) for the machining of β-phase titanium (β-Ti) alloy has been proposed. β-Ti alloys are new range of titanium alloys, which has a wide-spread application in dental, orthopedics, shape memory, and stents. The aim of the present study is to fabricate submicro- and nanoscale topography by PMEDM process to enhance the biocompatibility without affecting machining efficiency. The effect of Si powder concentration along with pulse current and duration on the surface and machining characteristics has been investigated. A significant decrease in surface crack density on the machined surface with 4 g/l Si powder concentration was observed. When β-Ti alloy was modified at 15 A pulse current, longer pulse interval with 8 g/l concentration of Si powder particles, the interconnected surface porosities with pore size 200–500 nm was observed. Moreover, at Si powder concentrations of 2 g/l and 4 g/l, the recast layer thickness is 8 µm and 2–3 µm, respectively. Elemental mapping analysis confirmed that PMEDM also generated carbides and oxides enriched surface, a favorable surface chemistry to enhance the biocompatibility of β-Ti alloy. Furthermore, PMEDM also enhances the machining performance by improving material removal rate and reducing tool wear rate.     

Effects of Hall current and two temperatures in transversely isotropic magnetothermoelastic with and without energy dissipation due to ramp-type heat

The present article is concerned with the investigation of disturbances in a homogeneous transversely isotropic thermoelastic rotating medium with two temperatures, in the presence of the combined effects of Hall currents and magnetic field. The formulation is applied to the thermoelasticity theories developed by Green-Naghdi theories of type-II and type-III. Laplace and Fourier transform techniques are applied to solve the problem. The analytical expressions of displacements, stress components, temperature change, and current density components are obtained in the transformed domain. A numerical inversion technique has been applied to obtain the results in the physical domain. Numerical simulated results are depicted graphically to show the effect of Hall current and two temperatures on resulting quantities. Some special cases are also deduced from the present investigation.