Cavity Wall Thickness Research Articles

The Effect of a Synbiotic Diet on Bone Structure in Aging Male Mice

This study aims to determine the effect of a synbiotic diet on the structural properties of femur bones in aging male mice. We hypothesize that a synbiotic diet will have an enhancing effect on bone structure that results in improved bone strength. Mice were divided into three groups: 10‐mo‐old sacrificed at baseline (BSL), 10‐mo‐old fed a standard rodent diet for 4 months (CON), and 10‐mo‐old fed the standard rodent diet enhanced with synbiotics for 4 months (SYN). The CON and SYN diets were isocaloric, with the synbiotic diet containing a prebiotic fructooligosaccharide (3% wt) and the probiotic strains Lactococcus lactis lactis and Lactobacillus acidophilus (1% wt). Images of the femur were obtained using micro‐computed tomography. NIH ImageJ was used to measure cortical wall thickness and cross‐sectional areas of total bone, cortical bone, and medullary cavity of the cortical shaft at 30%, 50%, and 70% of total bone length. Preliminary data shows that remodeling occurred between ages 10 to 14 months in mice fed the CON and SYN diets, with an enhancing effect of the SYN diet. Specifically, mice fed the control diet showed an age‐related decrease in cortical wall thickness (50% and 70% regions), while mice fed the synbiotic diet maintained (70% region) or increased (30% and 50% regions) cortical wall thickness with aging from 10 to 14 months. Because of these structural enhancements, it is predicted that the femur bones of mice fed the synbiotic diet will have improved bone strength. Supported by CSU‐Pueblo SEED Grant and Idaho State University.

CT features in peripheral lung cancer with thin-walled cavity

Objective To study the CT features of peripheral lung cancer with thin-walled cavity, and to improve the understanding and diagnostic accuracy of this type of lung cancer. Methods Thirty-one patients (male:18, female:13, average age (56±12) years old) with surgically proven peripheral lung cancer with thin-walled cavity were studied retrospectively. There were 28 cases of adenocarcinoma, 2 cases of squamous cell carcinoma and 1 case of sarcomatoid carcinoma. All patients had MSCT examination, and the CT features of the solid lesion and thin-walled cavity of the lung cancer were analyzed. The relationship between solid lesion and thin-walled cavity location, cavity wall thickness and uniformity, wall nodules, vascularstructures close to the outer wall, septum or air-fluid level inside the cavity, and dynamic changes of the lesions were all evaluated. Results (1) Solid lesion: mostly located in both upper and middle lobes of the lung in 21cases (67.7%). Lobulation, speculation and vessel convergence sign were observed in 27 cases (87.1%), 21 cases(67.7%)and 16 cases(51.6%) respectively. Twenty cases showed as ground glass nodule (GGN) (64.5%), with pure GGN in 11 cases(35.5%). (2) Cavitary lesion: The average diameter was (2.7±1.3) cm, the cavity located in the periphery of the solid lesions in 26 cases (83.9%),and in 20 cases (64.5%) located in the lateral or superior and inferior lateral aspect of the solid lesion; The cavity wall was uniform in17 cases (54.8%) and the wall thickness<2 mm were seen in 16 cases (51.6%), 2-3 mm were observed in 10 cases (32.3%); Wall nodules were seen in five cases (16.1%); Blood vessels adjacent to outer wall were found in 12 cases (38.7%); There was no air-fluid level in the cavity in all the cases; But septum with uneven thickness or small vessels were seen in the cavity in 27 cases (87.1%). Conclusions The majority of peripheral lung cancer with thin-walled cavity was adenocarcinoma, characteristic CT features of thin-walled cavitary lesions may be helpful in the diagnosis of this type of lung cancer. Key words: Lung neoplasms; Tomography, X-ray computed; Diagnosis, differential

Improving the stratification power of cardiac ventricular shape

Background Cardiac MRI has become the reference imaging modality used to assess left ventricular (LV) remodelling. Ventricles are generally characterised by bulk metrics such as cavity volume, mass or wall thickness. We introduce a workflow that aims to improve the stratification power of conventional analysis by providing 3D shape metrics through the construction of computational cardiac atlases.

Abstract 18343: Antisynthetase Syndrome-Associated Myocarditis

Background: The antisynthetase (AS) syndrome is characterized by fever, non-erosive arthritis, inflammatory myopathy, interstitial lung disease, cutaneous involvement, and antibody specificity. Cardiac involvement is extremely rare; we present one of two cases of AS syndrome-associated myocarditis from our institution. Clinical Case: A 51 year old woman with history of inflammatory arthritis and hypothyroidism presented with 6 months of increasing fatigue, bilateral proximal muscle weakness, leg edema, dyspnea, and orthopnea. Physical examination revealed a Caucasian woman, markedly dyspneic while speaking, with signs of acute decompensated heart failure (HF) including elevated jugular venous pulse, bilateral rales, S3 gallop, and massive peripheral edema with bilateral proximal upper and lower extremity weakness. Diagnostic Testing: Her muscle weakness was concerning for myopathy along with new HF symptoms. Laboratory studies revealed elevations of serum creatine kinase, aldolase, and cardiac troponin I. Thyroid stimulating hormone and free T4 were consistent with subclinical hypothyroidism. MRI and electromyography of the lower extremities and skeletal muscle biopsy were consistent with myositis. Anti-Jo1 antibody was positive, confirming the diagnosis of AS syndrome. Electrocardiogram showed sinus rhythm and low-voltages in all leads. Echocardiography showed severely depressed biventricular function, left ventricular (LV) ejection fraction of 10-15%, normal LV cavity size and wall thickness. Cardiac MRI and endomyocardial biopsy revealed active myocarditis. She received pulse dose corticosteroid therapy, intravenous furosemide, inotropic therapy, and hemofiltration therapy for renal failure. She was discharged home on intravenous dobutamine palliative therapy. Two months later, she presented in cardiogenic shock, failed intensive medical therapy, and died after a cardiac arrest. Conclusions: AS syndrome is a rare entity not typically associated with cardiac involvement. We report one of only two known cases of AS syndrome-associated myocarditis, to our knowledge. Based on these observations, we suggest that myocarditis be considered and evaluated for in patients with AS syndrome presenting with HF.

Abstract 13015: Cardiac Tamponade as a Rare Presentation of Chronic Lymphocytic Leukemia

An 89 year old male with a past medical history of CAD , diastolic HFpEF, HTN, HLD, DM, sick sinus syndrome with permanent pacemaker, OSA presented to the office with complaints of fatigue and progressive exertional dyspnea for 2 weeks. On examination his BP was 86/61mm Hg with a systolic drop of 20mmhg during inspiration by palpatory method, RR was 24 breaths/min, HR was 64 bpm, O2 sat. was 85% on RA. JVP was raised at 15cm. Cardiopulmonary examination revealed distant heart sounds, bibasilar crepitations and mild bilateral pedal eema. No lymphadenopathy was palpable. Initial lab assessment showed Hb of 9.5gdl, WBCs of 14.3 K/ul, potassium of 6.2mmol/, increased BUN/Creatinine ratio of 67/1.7, LDH of 642 U/L, Troponin I of 0.04ng/ml and BNP of 338pg/ml. EKG demonstrated av-paced rhythm without any evidence of electrical alternans or low voltage. CXR showed significant cardiomegaly. Transthoracic echocardiogram revealed normal LV cavity size, wall thickness and systolic function. A large pericardial effusion with early right ventricular diastolic collapse suggesting tamponade. The patient underwent emergent closed pericardiocentesis with complete resolution of symptoms. . Pericardial fluid analysis showed glucose of 78mg/dl, protein of 4.2g/dl, PH of 7.21, LDH of 1913 U/L, 1195000/uL RBCs, 212427/uL nucleated cells(Differential count N 3%, L 93%, M 2%, E 2% and B 0). Cytology was positive for PAX-5, CD-5 and negative for Cyclin-D1 &amp; CD-10 which was consistent with CLL. The patient was evaluated by the oncologist and he was started on rituximab and bendamustine. Follow up echocardiograms did not show any recurrence of effusion. The presence of pulsus paradouxs with other signs including hypotension, muffled heart sounds and raised jugular venous pressure greatly increases its sensitivity for cardiac tamponade which was evident in this case. Our case is unique because cardiac tamponade is rarely reported as an initial presentation of Chronic Lymphocytic Leukemia.

58 Changes in Left Ventricular Force, Velocity and Power Early After CABG

BackgroundA precise understanding and quantification of myocardial contraction is essential for optimising peri-operative care in high risk CABG surgery. Conventional approach has been focused on the magnitude of myocardial contraction,...

Influence of adhesive techniques on fracture resistance of endodontically treated premolars with various residual wall thicknesses

The choice of restorative method is commonly based on the cavity configuration and the residual number of cavity walls. However, the residual wall thickness could be a valuable clinical parameter in the choice of restoration for endodontically treated teeth. The fracture resistance of endodontically treated premolars was compared with different wall thicknesses restored with direct composite resin with and without cuspal coverage and with and without fiber post insertion. This study included 104 intact human maxillary premolars extracted for periodontal or orthodontic reasons. Standardized mesio-occluso-distal cavities were prepared with different palatal wall thicknesses (1.5, 2, and 2.5 mm) and a buccal wall thickness of 2 mm. Teeth were restored with or without a fiber post and with or without cuspal coverage. Specimens were subjected to thermocycling (3000 cycles, 5 to 55°C) and embedded in polymerized acrylic resin. Teeth were submitted to cyclic fatigue followed by a static fatigue test with a universal testing machine; a compressive force was applied 30 degrees to the long axis of the teeth until fracture. The results were statistically analyzed by 3-way ANOVA (α=.05). Residual wall thickness (P=.004), the type of adhesive restoration (P<.001), and fiber post insertion (P<.001) significantly influenced the fracture resistance of endodontically treated premolars. In specimens with a cavity wall thickness >2 mm, direct intracuspal composite resin restorations supported by a fiber post achieved comparable fracture resistance. With a residual wall thickness<2 mm, only cuspal coverage with or without a fiber post provided satisfactory fracture resistance.

Coated Composite Crosstie Mold Structure Design Used for Experiment with Inventor, Moldflow and Ansys

Coated crosstie products and counter mold components are created in 3-D model using Inventor software, preparing for CAE analysis. By using Moldflow software , to determine products gate location, filling, packing, cooling, push-out processing, as well as the injection process conditions optimization of simulation analysis to find possible defects, modify and optimize the design, determine the best processing parameters and conditions. Binding using Ansys11.0 software to analyze rail sleeper mold cavity deformation, structure stress, get distribution of property of von Mises stress and displacement vector sum, in the mold cavity on the contact surface. By changing the cavity wall thickness, and other factors to improve the force which it is subjected, providing references to structure optimization of injection mold design. It has been proven that in collaborative application of these three softwares, the design of the injection mold is a very efficient and easy.

157 CARDIOVASCULAR ADAPTATION IN ATHLETES OF SOUTH ASIAN ORIGIN: RELEVANCE TO UNIVERSAL IMPLEMENTATION OF PRE-PARTICIPATION CARDIOVASCULAR SCREENING

Introduction Regular physical exercise results in structural and electrophysiological cardiac changes, referred to as ‘athletes’ heart9. Ethnicity is an important determinant of such adaptation in athletes; it has been demonstrated that Afro-Caribbean (AC) athletes exhibit a greater degree of cardiac adaptation compared to Caucasian athletes (CA). However, there is conspicuous lack of data on cardiac adaptation in Asian athletes, particularly those of South Asian (SA) origin. This study describes the ECG and echocardiographic characteristics in competitive athletes of SA descent. Methods Between 2011 and 2012, 100 male SA athletes (age 14–35) underwent pre-participation cardiovascular screening with ECG and echocardiography. These athletes participated in cricket (n=40), football (n=27), hockey (n=25) and racquet sports (n=8), and they trained on average 12±6.6 h every week. The ECG findings were classified as Group-1 (training-related) or Group-2 (training-unrelated); and data on cardiac chamber size and wall thickness was obtained using standard echocardiogram. Results were compared with 80 CA and 40 AC athletes, and with 30 South Asian controls. Results The group-1 and group-2 ECG changes were seen in 55% and 9% athletes respectively. Minor T-wave inversions were observed in only 3%, whereas none of the athletes had deep T-wave inversions. The mean LA and LV cavity dimensions were 33.2±4 mm (range 20–42) and 49.5±4.4 mm respectively. Only 2% athletes exhibited an LV dimension of ≥60 mm; an LA ≥40 mm was seen in 5% athletes. The mean LV wall thickness was 9.2±1 mm. None of the athletes had LV wall thickness of >12 mm. A cardiomyopathy was not identified in any athlete. The ECG abnormalities, particularly T-wave inversions were less prevalent in SA athletes compared to AC athletes (p Conclusions The South Asian male athletes demonstrate similar ECG changes to Caucasians, but fewer ECG anomalies compared to Afro-Caribbean athletes. However they exhibit a lesser degree of structural cardiac adaptation which may be influenced by body size and type of sport. The ESC criteria for interpretation of athletes9 ECG may be applicable to South Asian athletes, and upper limits of cardiac cavity dimensions and wall thickness do not differ from Caucasian population. Larger studies are required in this ethnic group.

Influence of cavity design preparation on stress values in maxillary premolar: a finite element analysis

AimTo analyze the influence of cavity design preparation on stress values in three-dimensional (3D) solid model of maxillary premolar restored with resin composite.Methods3D solid model of maxillary second premolar was designed using computed-tomography (CT) data. Based on a factorial experiment, 9 different mesio-occlusal-distal (MOD) cavity designs were simulated, with three cavity wall thicknesses (1.5 mm, 2.25 mm, 3.0 mm), and three cusp reduction procedures (without cusp reduction, 2.0 mm palatal cusp reduction, 2.0 mm palatal and buccal cusp reduction). All MOD cavities were simulated with direct resin composite restoration (Gradia Direct Posterior, GC, Japan). Finite element analysis (FEA) was used to calculate von Mises stress values.ResultsThe von Mises stresses in enamel, dentin, and resin composite were 79.3-233.6 MPa, 26.0-32.9 MPa, and 180.2-252.2 MPa, respectively. Considering the influence of cavity design parameters, cuspal reduction (92.97%) and cavity wall thickness (3.06%) significantly (P < 0.05) determined the magnitude of stress values in enamel. The influence of cavity design parameters on stress values in dentin and resin composite was not significant. When stresses for enamel, dentine, and resin composite were considered all together, palatal cusp coverage was revealed as an optimal option. Cavity wall thickness did not show a significant effect on stress values.ConclusionBased on numerical simulations, a palatal cusp reduction could be suggested for revealing lower stress values in dental tissues and restorative material. This type of cavity design should contribute to better biomechanical behavior of tooth-restoration complex, consequently providing the long-lasting clinical results.

Investigating the Possibility of Chemi-mechanical Pulping of Bagasse

Chemi-mechanical pulping was evaluated as a potential way to prepare sugarcane bagasse fibers for papermaking. Cellulose, lignin, ash, and extractives soluble in alcohol-acetone were measured as 55.75%, 20.5%, 1.85%, and 3.25%, respectively. Fiber length, diameter, lumen cavity, and cell wall thickness were measured as 1.59 mm, 20.96, 9.72, and 5.64 µm. The chemi-mechanical pulping conditions were selected as follows: three charging levels of 10, 15, and 20% sodium sulphite, and three pulping times of 20, 30, and 40 minutes after reaching the pulping temperature. Pulping temperature was held constant at 165 oC. Different pulping conditions resulted in pulp yields between 65.38 and 84.28%. The highest yield (84.28%) was obtained using a treatment combination of 20 minutes pulping time and 10% sodium sulphite. The lowest yield (65.38%) was related to 40 minutes pulping time and 20% sodium sulphite. Pulps were refined to 300 ± 25 mL CSF, 60 gm-2 handsheets were made, and then strength indices and optical properties of the handsheets were measured. The results showed that 20% sodium sulphite, 40 minutes pulping time, at 165 oC can be considered as the optimum pulping conditions for bagasse CMP pulping. Tensile, tear, and burst strength indices, as well as the opacity of this pulp were measured as 39.59 Nmg-1, 6.66 mNm2g-1, 2.1 KPa m2g-1, and 95.35%, respectively.

Diagnostic accuracy and safety of CT-guided fine needle aspiration biopsy in cavitary pulmonary lesions

ObjectiveCT-guided transthoracic biopsy is a well-established method in the cytologic or histologic diagnosis of pulmonary lesions. The knowledge of its diagnostic performance and complications for cavitary pulmonary lesions is limited. The purpose of this study was to determine the diagnostic accuracy and safety of CT-guided fine needle aspiration biopsy (FNAB) in cavitary pulmonary lesions. Materials and methods102 consecutive patients with pulmonary cavitary lesions received CT-guided FNAB with use of an 18-gauge (n=35) or 20-gauge (n=67) Chiba for histology diagnosis. The sensitivity, specificity, and diagnostic accuracy of FNAB were calculated as compared with the final diagnosis. Complications associated with FNAB were observed. The diagnostic accuracy and complications were compared between patients with different lesion sizes and different cavity wall thickness. ResultsThe overall sensitivity, specificity, and accuracy of FNAB were 96.3%, 98.0%, and 96.1%, respectively. The sensitivity, specificity, and diagnosis accuracy in different lesion size (<2cm vs ≥2cm), or different cavity wall thickness (<5mm vs ≥5mm) were not different (P>0.05; 0.235). More nondiagnostic sample was found in wall thickness <5mm lesions (P=0.017). Associated complications included pneumothorax in 9 (8.8%) patients and alveolar hemorrhage in 14 patients (13.7%) and hemoptysis in 1 patient (1%). No different rate of complications was found with regard to lesion size, wall thickness, length of the needle path and needle size (P>0.05). ConclusionCT-guided FNAB can be effectively ad safely used for patients with pulmonary cavitary lesions.

The Morganroth hypothesis revisited: endurance exercise elicits eccentric hypertrophy of the heart

The Morganroth hypothesis revisited: endurance exercise elicits eccentric hypertrophy of the heart

The Influence of Body Composition, Fat Distribution, and Sustained Weight Loss on Left Ventricular Mass and Geometry in Obesity

Alterations in left ventricular mass and geometry vary along with the degree of obesity, but mechanisms underlying such covariation are not clear. In a case-control study, we examined how body composition and fat distribution relate to left ventricular structure and examine how sustained weight loss affects left ventricular mass and geometry. At the 10-year follow-up of the Swedish obese subjects (SOS) study cohort, we identified 44 patients with sustained weight losses after bariatric surgery (surgery group) and 44 matched obese control patients who remained weight stable (obese group). We also recruited 44 matched normal weight subjects (lean group). Dual-energy X-ray absorptiometry, computed tomography, and echocardiography were performed to evaluate body composition, fat distribution, and left ventricular structure. BMI was 42.5kg/m(2), 31.5kg/m(2), and 24.4kg/m(2) for the obese, surgery, and lean groups, respectively. Corresponding values for left ventricular mass were 201.4g, 157.7g, and 133.9g (P < 0.001). In multivariate analyses, left ventricular diastolic dimension was predicted by lean body mass (β = 0.03, P < 0.001); left ventricular wall thickness by visceral adipose tissue (β = 0.11, P < 0.001) and systolic blood pressure (β = 0.02, P = 0.019); left ventricular mass by lean body mass (β = 1.23, P < 0.001), total body fat (β = 1.15, P < 0.001) and systolic blood pressure (β = 2.72, P = 0.047); and relative wall thickness by visceral adipose tissue (β = 0.02, P < 0.001). Left ventricular adjustment to body size is dependent on body composition and fat distribution, regardless of blood pressure levels. Obesity is associated with concentric left ventricular remodeling and sustained 10-year weight loss results in lower cavity size, wall thickness and mass.

English

In the present work best shell wall thickness of mould cavity has been investigated for process capability study of rapid casting solution for aluminum alloys using three dimensional printing (3DP). Starting from the identification of component/ benchmark, aluminum-alloy casting prototype was produced at different shell wall thickness with three dimensional printing. The results of the study suggests that at best shell wall thickness (5mm) for aluminum alloys, rapid casting solution using 3DP process lies in ±3.999 sigma (@) limit.

Comparison of Hybrid Rapid Mouldings for Zinc Alloy Castings

In this work comparison of hybrid rapid moulds (prepared with three dimensional printing shells supported with dry, green and molasses sand) have been made for techno-economic analysis, for zinc (Zn) alloy shell casting. The comparison has been made on the basis of mechanical properties and dimensional accuracy. Time-temperature curves have been drawn to understand solidification of molten Zn alloy in hybrid moulds of different thicknesses. The results of study suggest that it is feasible to reduce shell wall thickness of hybrid mould cavity from recommended 12mm to 1mm. All castings prepared are consistent with the permissible range of IT grades and are acceptable as per ISO standard UNI EN 20286-1 (1995). Further green sand based hybrid prototypes at 3mm shell wall thickness, shows better dimensional accuracy and mechanical properties.

Analysis and Research of Piezoelectric Dynamic Weighing Sensor

The Kistler company has invented piezoelectric dynamic weighing sensors which are applied to determine dynamically axle load, speed and gross weight of the vehicle based on piezoelectric effect of quartz crystal. They mainly consist of load-carrying beams and sensitive elements. Focusing on the control of preload in design and fabrication, finite element method (FEM) is applied with ANSYS software to optimize structural sizes. The influence curve of the structural dimensions of load-carrying beam on the preload is analyzed. With the piezoelectric coupling analysis function, the preload influence on the sensor sensitivity is researched. FEM simulation results show that the critical dimensions of load-carrying beam as well as the deformation and wall thickness of cavity have significant impact on the preload. Further studies show that the sensor has the highest sensitivity with the reasonable deformation and wall thickness of the cavity. In this paper, a sensor with range of 150 kN has the highest sensitivity at the wall thickness of 2 mm and the deformation of 0.14 mm.

Effect of Work Piece Dimensions on Cost Effective Hybrid Rapid Casting Solution for Aluminium Alloy

The purpose of the present experimental investigations is to study the effect of work piece dimensions on reducing the shell wall thickness of mould cavity for cost effective, hybrid rapid casting solution of aluminum alloy. Starting from the identification of component/benchmark, technological prototypes with three different work piece dimensions (volume/ weight) were produced, at different shell wall thickness of mould cavity using hybrid rapid prototyping technique (combination of three dimensional printing and conventional sand casting). Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings. The study suggested that the shell wall thickness, having value less than the recommended one is more suitable from dimensional accuracy and economic point of view, for all three work piece dimensions (volume/ weight). Further best shell wall thickness of the mould cavity for different work piece dimensions of the selected benchmark has been highlighted for rapid casting solution of aluminum alloy.

Effect of Moulding Sand Properties on Cost Effective Hybrid Rapid Casting Solution for Zinc Alloy

The purpose of the present experimental investigations is to study the effect of moulding sand properties on reducing the shell wall thickness of mould cavity for cost effective, hybrid rapid casting solution of zinc alloy. Starting from the identification of component/benchmark, technological prototypes were produced, with three different moulding sands (dry, green and molasses), at different shell wall thickness of mould cavity using hybrid rapid prototyping technique (combination of three dimensional printing and conventional sand casting). Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings. The study suggested that for the shell thickness, having value less than the recommended one is more suitable from dimensional accuracy and economic point of view, for all three moulding sands. Further best shell wall thickness of the mould cavity for different moulding sands, for the selected component/benchmark has been highlighted for rapid casting solution of zinc alloy.

The incognita of the known: the athlete’s heart syndrome

Long-term athletic activity causes morphological and functional changes in the heart characterized as left ventricle cavity dimension changes, wall thickness and mass increase and rhythm conduction changes. This condition is identified as "athlete's heart syndrome". The changes that are seen clinically occur as a result of physiological adaptation to exercise. Cardiovascular adaptation depends on the exercise's type as well as its frequency, duration and intensity. In the athlete's physical examination, various changes can be seen that are mistaken with pathological conditions. In addition, there are changes present due to cardiac hypertrophy, increased vagal tone and repolarization. The knowledge and recognition of the organic and functional changes developing in the athlete's heart is being helpful to differentiate physiological changes from cardiac pathologies that can cause sudden death in athletes.