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A 40-year-old woman presented with dull, boring periumbilical region pain radiating to the back and vomiting for 1 year. Magnetic resonance cholangiopancreatography detected a polypoid growth in the ampullary region. The patient underwent Whipple's procedure. The specimen revealed a 4.9 x 4.5 x 3.7 cm tumor arising from the pancreas, abutting the posterior pancreatic surface and infiltrating the terminal common bile duct and the ampulla. Microscopic examination showed a pancreatic tumor composed of neuroendocrine cells. In addition, many large foci showing solid sheets of oncocytic cells with abundant granular eosinophilic cytoplasm were observed. Immunohistochemistry studies revealed positivity for synaptophysin, chromogranin, and Ki67 index above 70%. A diagnosis of oncocytic neuroendocrine tumor of Grade 3 was made. In electron microscopy, oncocytic cells showed abundant mitochondria dispersed throughout the cytoplasm. Oncocytic pancreatic neuroendocrine neoplasms are uncommon and can be diagnosed only on histopathological examination. These tumors tend to show a malignant behavior. Keywords: Electron microscopy, neuroendocrine tumor, oncocytic tumor, pancreatic tumor, Author(s): Divya Shetty [1]; Aditi Raj [1]; Anjali Amarapurkar (corresponding author) [1] Introduction Pancreatic neuroendocrine tumors (PanNETs) account for approximately 3% to 4% of adult pancreatic neoplasms.[sup.[1]] Oncocytic PanNET is [...]

Solar water pumps are crucial for farmers, significantly reducing energy costs and providing independence from conventional fuels. Their adoption is further incentivized by government subsidies, making them a practical choice that aligns with sustainable agricultural practices. However, the cost of the required solar panels for the chosen power makes it essential to optimize solar water pumping systems (SWPS) for economic viability. This study enhances the efficiency and reliability of permanent magnet synchronous motor (PMSM)-driven SWPS in rural areas using hybrid maximum power point tracking (MPPT) algorithms and voltage-to-frequency (V/f) control strategy. It investigates the sensorless scalar control method for PMSM-based water pumps and evaluates various MPPT algorithms, including grey wolf optimization (GWO), particle swarm optimization (PSO), perturb and observe (PO), and incremental conductance (INC), along with hybrid combinations. The study, conducted using MATLAB Simulink, assesses these algorithms on convergence time, MPPT accuracy, torque ripple, and system efficiency under different partial shading conditions. Findings reveal that INC-GWO excels, providing higher accuracy, faster convergence, and reduced steady-state oscillations, thus boosting system efficiency. The V/f control strategy simplifies control mechanisms and enhances performance. Considering system non-idealities and maximum duty cycle limitations, PMSM-based SWPS achieve superior efficiency and stability, making them viable for off-grid water pumping applications. [ABSTRACT FROM AUTHOR]

Restorative dentistry is the repairing of damaged teeth and restoring oral health and function. Dental implants are typically placed within the cortical bone of the jaw to provide stability and support for prosthetic restorations. The successful restoration of complex anatomical features of the maxillary anterior is difficult for prosthodontists. Using a 3D slicer, CT scan images were used to create a detailed three-dimensional model of the maxilla bone. This study utilizes ANSYS Workbench, a finite element software program, to analyze the abutment angles, ranging from 0° to 25°, and the impact stress distribution within peri-implant bone. The outcomes of our studies align with and substantiate certain evidence in the literature documenting bone resorption, specifically at the level of the implant neck and near the cortical bone. The study aims to provide a comprehensive understanding of angled abutment stress patterns in the bone surrounding dental implants, offering valuable insights for clinical applications in critical areas of the mouth. [ABSTRACT FROM AUTHOR]

In dental implant insertion, an artificial foundation is prepared for the prosthetic device, which involves the surgical positioning of the implant in the jaw bone. The success of dental implants relies on the osseointegration process. The biomechanical factors, such as stress and strain, developed during the insertion affect the jawbone and its surroundings. In this current study, the stresses during the implant insertion in the mandibular jawbone bone are analyzed using three-dimensional explicit dynamic analysis, and the Cowper–Symonds model is implemented with the damage model. The implant's design has a substantial impact on stress distribution within the cancellous bone during the insertion procedure. The stress variation takes place as the implant moves into the pre-drilled hole. This is because of the contact between the bone and the fixture on the implant. The upper edge of the predrilled site shows that the stresses are more at the crestal region of the implant due to surface area. There is a gradual increase in the stress level as the implant reaches the lower edge from the top edge. This is because of the concept of mechanical interlocking. Clinicians can use this information to anticipate and address potential stress-related challenges during implant placement. [ABSTRACT FROM AUTHOR]

The selection of abrasive material and parameters of the Air-Abrasion device for a particular application is a crucial detail. However, there are no standard recommendations or manuals for choosing these details; the operator must depend on his experience and knowledge of the procedure to select the best possible material and set of parameters. This short review attempts to identify some of the effects that the selection of material and parameters could have on the performance of the Air-Abrasion procedure for a particular application. The material and parameter data are collected from various studies and categorized according to the most popular materials in use right now. These studies are then analyzed to arrive at some inferences on the performance of Air-Abrasion materials and parameters. This review arrives at a few conclusions on the effectiveness of a material and parameter set, and that there is potential for developments in the area of standardizing parameter selection; also, there is scope for further studies on Bio-Active Glass as an alternative to the materials currently used in Air-Abrasion. [ABSTRACT FROM AUTHOR]

Purpose: The present study aimed to assess the accuracy and reproducibility of laser-scanned digital models compared to plaster models. Materials and Methods: A total of 50 plaster models were scanned using the 3M ESPE Lava scan ST scanner to construct digital models. Various measurements, encompassing intra-arch and inter-arch from scans and plaster models, were estimated. The plaster models were measured using digital calipers and digital models using MiniMagics 3.0 software. Descriptive statistics were calculated, and the mean difference of the parameters between the two groups was tested by paired t-test. Results: No significant difference was detected between the digital and manual measurements in the majority of the parameters, and the values for the parameters showed significant differences that were not clinically applicable. The digital method showed good reproducibility for all the measurements (r > 0.7). Overbite showed a marked variation between the manual and digital measurements due to overlapping tooth structures in digital models with respect to ideal occlusion. Bolton's analysis did not show a significant difference between the manual and digital methods. Conclusions: Digital models could be compared to the gold standard plaster models. [ABSTRACT FROM AUTHOR]

The solar water pumping systems (SWPS) is useful in remote or village areas where there is no electricity. In India, SWPS are revolutionizing agriculture by giving farmers access to power for everything, from harvesting crops to pumping water. As the government is working to make solar pumping systems affordable for the agricultural sector, induction motors (IM) are found to be the most appropriate motor type for this application because of its low cost, durability and ruggedness. In this work, the SWPS is powered by an inverter driven three-phase IM with V/f control technique. Various MPPT techniques have been proposed to track maximum power from PV system under partial shading condition. This paper mainly focuses on a hybrid Particle Swarm Optimization-Incremental Conductance (PSO-INC) algorithm to capture the peak power efficiently when IM based SWPS is subjected to partial shading. The results are compared with PSO algorithm, a hybrid PSO-PO method and a modified 0.8 Voc approach. The MATLAB/Simulink environment is used to simulate and test these algorithms on the SWPS system with partial shading. The motor's performance in terms of torque ripple and speed settling time is analyzed. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate the efficacy of non-aerosol producing restorative self-etching primers (SEPs) as a substitute for conventional orthodontic bonding primers and to analyze the extent of residual composite on the tooth post-debonding. MATERIALS AND METHODS: Eighty-four extracted human premolars were randomly divided into seven groups based on the adhesive and the bonding protocol used. The study comprised Prime and Bond one select (Dentsply), G-Premio Bond (GC), which were each divided into three subgroups based on the method used for moisture control and the control group (Transbond XT conventional total etch). The three methods for moisture control in study groups were: without drying, air-drying with the use of a three-way syringe, and with the use of blotting paper. Shear bond strength (SBS) was tested using a universal testing machine (UTM), and after debonding, the enamel surface of each tooth was examined under 10× magnification to evaluate adhesive remaining index (ARI) scores. RESULTS: Groups 2A (Prime and Bond; without drying) & 1 (Transbond XT) had the lowest and highest SBS values, respectively (P = 0.001). Comparison of ARI between the control group and group 2b (Prime and Bond; air-drying with 3 in 1) showed a significant difference (P = 0.041). Comparison of ARI between control group and group 2c (Prime and Bond; blotting paper) showed a significant difference (P = 0.017). Rest all other comparisons were non-significant. CONCLUSIONS: Transbond XT had SBS values higher than the self-etch groups. Among the self-etch groups, G-Premio Bond had higher SBS values when the traditional methods of air-drying were followed. Use of blotting paper for drying that produced variable SBS values can be an effective alternative method. G-Premio Bond with its adequate bond strength under manufacturer's instruction seems promising in this regard. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the treatment outcomes between Twin Block and AdvanSync2® appliances by comparing the skeletal, dentoalveolar, and soft tissue changes. Materials and Methods: Radiographic data of 20 patients were retrospectively analyzed. Data were selected from patients in their skeletal growth spurt as evaluated by the cervical vertebral maturation method (CVMI 2, 3, and 4), with class II malocclusion characterized with retrognathic mandible (ANB > 4°, SNB < 77°, FMA = 25 ± 5°, overjet > 5 mm). There were 10 patients in each group that underwent orthodontic correction for class II malocclusion: either using Twin Block or AdvanSync2®. Independent t test and Paired t test and chi-square tests were used for the data analysis. The level of statistical significance was set at P value =.05. Results: The chronological and skeletal age were similar in both the groups. Records were taken for the functional treatment with mean treatment span of 8 ± 1 month. Changes in SNB (group I = 1.59°, group II = 3.11°) (P < .01), Co-Gn (group I = 2.89 mm, group II = 5.34 mm), and U1-L1° (group I = -1.51°, group II = 2.97°) showed statistically different outcome between the groups, when the pre-post data were studied. Rest of the variables--cranial base, maxillary skeletal, mandibular skeletal, intermaxillary, vertical skeletal, maxillary dentoalveolar, mandibular dentoalveolar, and soft tissue--showed similar outcome (P > .05). Conclusion: Both appliances lead to desirable outcomes in the correction of class II malocclusion. AdvanSync2® resulted in inducing more of changes in SNB and effective mandibular length as compared to Twin Block. Overjet and molar relation improved significantly with both the appliances. Both the appliances resulted in similar skeletal, dentoalveolar, and soft tissue changes. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this study was to assess the sealing ability of Biodentine (BD) and mineral trioxide aggregate (MTA) as retrograde filling materials after irrigation with 17% ethylenediaminetetraacetic acid (EDTA) and QMix irrigating solutions. Materials and Methods: Decoronation of 48 permanent maxillary central incisors was done. Root canal instrumentation was carried out in the samples. The apical root was resected for about 3 mm and retrocavities were prepared. Teeth were allocated into two groups (n = 24). MTA was used in Group 1. BD was used in Group 2. Depending on irrigation, the groups were subdivided A, B, and C subgroups. Group A - 0.9% saline; Group B - 17% EDTA; and Group C - QMix were used. The resected root end was irrigated with 5 ml of all irrigating solutions for 1 min. After final irrigation, cavities were filled with retrofilling materials in each group. Nail enamel was applied to the surfaces of the roots apart from the resected end. Roots were placed in India ink for 72 h. Teeth were sectioned longitudinally and microleakage was determined with a stereomicroscope. Statistical Analysis: Analysis was done using the one-way analysis of variance, Independent t-test, and post hoc test. Results: Statistically significant difference in the degree of microleakage was observed between irrigating solutions and the retrofilling materials. Conclusion: BD exhibits a better sealing ability compared to MTA as a retro filling material following QMix irrigation. [ABSTRACT FROM AUTHOR]

Mesenchymal hamartoma of liver (MHL) is a benign liver tumour that occurs mainly in children, especially those under 2 years old. The pathogenesis of this tumor is still unknown. It is believed that MHL is derived from the Ito cells and either a developmental malformation of primitive hepatic mesenchyme; result of toxic or ischemic insult; or a true neoplasm. It is amenable to treatment and has a good prognosis but presents with varied clinical, imaging and histological findings. However, it can be confused with other hepatic tumors and can mimic malignancy. Therefore, it is important to recognize this rare entity to avoid unnecessary over management. We present a case of MHL in a 3-year-old boy with abdominal distension. Based on the clinical presentation, laboratory and radiological findings a diagnosis of complex cyst of liver was made. A final diagnosis of MHL was given after histopathological examination. [ABSTRACT FROM AUTHOR]

Papillary endothelial hyperplasia (PEH) is a reactive pseudoneoplastic proliferation of endothelial cells. They are typically well-circumscribed, indolent lesions and curable by complete excision. Description: We present a four-year-old girl with post traumatic scalp swelling, clinically considered to be a capillary hemangioma. Computed tomography revealed a 3.3 × 1.5 cm scalp mass with erosion of outer table and diploic space of the occipital calvarial bone, suggesting a vascular or soft tissue tumor. Histologically it was a PEH within a hemangioma. Literature Review: PEH presenting as a scalp swelling with bone erosion has only been reported thrice in the literature. Conclusion: Scalp PEH with skull bone defect can affect the pediatric age group. Bone erosion is not stage dependent; it can occur in the early stages. [ABSTRACT FROM AUTHOR]