Triple intussusception involving heterotopic pancreatic tissue: a case report

<p>Abstract</p> <p>Introduction</p> <p>Intussusception involving heterotopic pancreatic tissue is a rare condition where a portion of the bowel telescopes into an adjacent segment with intraluminal pancreatic tissue as the lead point. Cases of heterotopic pancreas are most often described in the upper intestinal tract, particularly the stomach.</p> <p>Case presentation</p> <p>We present the case of a five-month-old boy of Caucasian ethnicity suffering acute abdominal pain and vomiting with an abdominal mass in the upper right quadrant. Work-up including ultrasound scan confirmed the intussusception. Repeated attempts at radiological reduction and two laparoscopic procedures were performed within 24 hours, which eventually led to the diagnosis of a triple intussusception.</p> <p>Conclusion</p> <p>To our knowledge, such a case of triple intussusception involving isolated heterotopic pancreatic tissue is previously unreported.</p

The Effects of Interbracket Position and Distance on the Orthodontic Triangular Loop

Indiana University-Purdue University Indianapolis (IUPUI)Orthodontic closing loops offer an efficient way to control the moment to force ratios (M/F) delivered during space closure. The triangular loop is often used in the Graduate Orthodontic Clinic at the Indiana University School of Dentistry. Previous studies on the triangular loop were concerned with various loop geometries. The present project was designed to study the triangular loop in a clinically realistic experimental set up. Compared to the previous studies, three major changes were implemented: instead of two coplanar brackets, the current study employed a bracketed typodont arch (1) the effects of loop locations (2) and different interbracket distances were considered (3). The measured moment and forces reflect considerable differences in the systems due to the new experimental set up. As in previous studies, the triangular loops were fabricated from 0.016 X 0.022- inch stainless steel wire. The loops were equilateral triangles with 8 mm sides, ligated to the arch wire by elastomeric rings. There were 4 loop locations: location 1 was at 1.2 mm away from the mesial bracket; location 2 was at 3 .2 mm away from the distal bracket; location 3 was centered in the middle of the original interbracket distance; location 4 was located 2.6 mm away from the mesial bracket. There were three interbracket distances (IB). The original IB (IBl) of 12.6 mm was decreased by 3 mm (IB 2) and by 6 mm (IB 3). The loops were activated by 1.6 mm and 3.3 mm. Force and moment components were measured along three mutual perpendicular axes (x, y, and z) corresponding to the buccolingual, mesiodistal, occlusogingival axes respectively. Comparisons of Mx/Fy and Mz/Fy at the mesial and distal, by three activation levels, three interbracket distances, and four locations, and all interaction effects, were performed using a mixed design repeated measures ANOV A procedure. The General Linear Model (GLM) procedure for unbalanced designs was used because not all interbracket distances could be accommodated with all loop locations. Activation distance was the within specimen repeated factor. Loop location and interbracket distance were the between specimen factor. It was theorized that the location of the triangular loop, as well as the interbracket distance, have a considerable effect on the generated M/F. The Null Hypothesis was that there are no significant differences (p > 0.05) in the M/F ratios generated by the triangular loop as the loop position changes relative to the brackets, and there are no significant differences (p>0.05) in the M/F ratios generated by the triangular loop as the interbracket distance becomes shorter with space closure. Statistical significant interactions were found for Mx/Fy and Mz/Fy at location 2, for all activations, at both the mesial and distal measures. Therefore we rejected the first part of the Null Hypothesis (no differences as the loop location changes), and accept the second part (no differences as the interbracket distance shortens). We were able to see clear trends at all loop locations, as well as interbracket distances, and draw useful clinical implications. We found that the mesial closing forces are quite small when compared to those at the distal. We attributed this discrepancy to the U shape geometry of the continuous arch wire technique. We observed that if closing loops are delivered with no activation, then counterproductive M/F ratios are produced. Our data also indicated that anchorage becomes more critical as the interbracket distance shortens. Finally, we determined that wire tie ligation for prevention of rotation along the long axis of the tooth is especially important for the lateral incisor

Approaching the Processes in the Generator Circuit Breaker at Disconnection through Sustainability Concepts

Nowadays, the electric connection circuits of power plants (based on fossil fuels as well as renewable sources) entail generator circuit-breakers (GCBs) at the generator terminals, since the presence of that electric equipment offers many advantages related to the sustainability of a power plant. In an alternating current (a.c.) circuit the interruption of a short circuit is performed by the circuit-breaker at the natural passing through zero of the short-circuit current. During the current interruption, an electric arc is generated between the opened contacts of the circuit-breaker. This arc must be cooled and extinguished in a controlled way. Since the synchronous generator stator can flow via highly asymmetrical short-circuit currents, the phenomena which occur in the case of short-circuit currents interruption determine the main stresses of the generator circuit-breaker; the current interruption requirements of a GCB are significantly higher than for the distribution network circuit breakers. For shedding light on the proper moment when the generator circuit-breaker must operate, using the space phasor of the short-circuit currents, the time expression to the first zero passing of the short-circuit current is determined. Here, the manner is investigated in which various factors influence the delay of the zero passing of the short-circuit current. It is shown that the delay time is influenced by the synchronous machine parameters and by the load conditions which precede the short-circuit. Numerical simulations were conducted of the asymmetrical currents in the case of the sudden three-phase short circuit at the terminals of synchronous generators. Further in this study it is emphasized that although the phenomena produced in the electric arc at the terminals of the circuit-breaker are complicated and not completely explained, the concept of exergy is useful in understanding the physical phenomena. The article points out that just after the short-circuit current interruption by the generator the circuit-breaker (when the GCB has been subjected at the metal contact terminals to the high temperature of a plasma arc, up to 50,000 K) between its opened contacts, there arises the transient recovery voltage (TRV) which constitutes the most important dielectric stress after the electric arc extinction. Since the magnitude and shape of the TRV occurring across the generator circuit-breaker are critical parameters in the recovering gap after the current zero, in this paper, we model, for the case of the faults fed by the main step-up transformer, the equivalent configurations, with operational impedances, for the TRV calculation, taking into account the main transformer parameters, on the basis of the symmetrical components method

Addressing the Impact of Environmental Xenobiotics in Coal-Fired Flue Gas

Dangerous and unstable situations can result from the presence of environmental xenobiotics since their harmful effects on humans and ecosystems are often unpredictable, and building awareness of the environmental risk should be a main concern of humankind. The environmental xenobiotics in the flue gas from a fossil fuel-fired electrical generating station, such as particulate matter (PM), sulfur dioxide (SO2), nitrogen oxides (NOx), and carbon dioxide (CO2), are analyzed in this study, since these xenobiotics are persistent pollutants. Mathematical models of the environmental pollutant vector, estimating the emission factors specific to fossil fuel combustion, are applied to the operation of thermal units in the Turceni electrical generating station, each of which produces a net electrical power of 330 MW. For each stack gas component in the pollutant vector, emission factors and pollutant concentrations are determined. A pattern is also examined depicting the mathematically modelled processes of resonant absorption of an environmental xenobiotic harmonic oscillation by an organism modulated as an absorbing oscillator structure. The xenobiotic concentration degree is represented through a spatial concentration vector, which allows further modelling and simulation of the oscillating regime of environmental xenobiotic absorption

Three-phase power transformer modelling in AC/DC traction substations

Three-phase power transformer is one of the most important elements in the electric power systems, and it plays a significant role in terms of energy savings. Since the efficiency standards can be expressed in terms of electrical efficiency, in an attempt to improve the transformer efficiency, in this study an enhancement of three-phase power transformer modelling with space phasors is presented. There are established the equations with space phasors of the three-phase transformer with symmetrical compact core. This equations system can be used to analyze the dynamic regimes of three-phase transformers. In this paper have been analyzed some aspects of three-phase power transformer operation in a AC/DC traction substation

OBEZITATEA LA COPIL – O PROBLEMĂ PEDIATRICĂ ÎN CREŞTERE

Obezitatea este cea mai comună tulburare de nutriţie la copil în ţările dezvoltate ale lumii (15-30% din adolescenţii din SUA), frecvenţa sa crescând îngrijorător şi în România. Obezitatea primei copilării este frecventă, prognosticul obezităţii fi ind cu atât mai nefavorabil cu cât momentul debutului este mai precoce şi cu cât excesul ponderal este mai mare. Obezitatea la vârsta adolescenţei reprezintă o problemă la nivel mondial. Prevalenţa supraponderalităţii şi a obezităţii a fost înregistrată în special în ţările din America de Nord, Marea Britanie şi sud-vestul Europei