Experimental investigation on sucrose/alumina catalyst coated converter in gasoline engine exhaust gas.

In this study, a modified catalytic converter was employed to treat the harmful exhaust gas pollutants of a twin-cylinder, four-stroke spark-ignition engine. This research mainly focuses on the emission reduction of unburnt hydrocarbons, carbon monoxide, and nitrogen oxides at low light-off temperatures. A sucrolite catalyst (sucrolite) was coated over the metallic substrate present inside the catalytic converter, and exhaust gas was allowed to pass through it. A scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectroscopy were used to investigate the changes in morphology, chemical compounds, and functional group elements caused by the reactions. Catalytic reactions were studied by varying the engine loads and bed temperatures, and the results were compared with those of the commercial catalytic converter. The results show that sucrose present in the catalyst was suitable at low temperatures while alumina was suitable for a wide range of temperatures. In the case of the modified catalytic converter, the maximum catalytic conversion efficiencies achieved for oxidizing CO and HC were 70.73% and 85.14%, respectively, and for reduction reaction at NOx was 60.22% which is around 42% higher than in commercial catalytic converter. As a result, this study claims that sucrolite catalyst is effective for low-temperature exhaust gas.

An experimental study of the effects of fuel injection pressure on the characteristics of a diesel engine fueled by the third generation Azolla biodiesel.

This study focuses on effectively utilizing the biodiesel extracted from Azolla (third-generation biofuel), which is regarded as a renewable energy source, for fueling diesel engines. Biodiesel is unique due to its increased viscosity and different fatty acid composition, which proved difficult to attain better engine performance with a mechanical type injection system. This study expands on the previous investigation in modifying the fuel system when using Azolla biodiesel by using a common rail fuel injection system with wider injection flexibility. Considering the lack of more engine optimization studies for Azolla biodiesel, a parametric study is conducted by changing the fuel injection pressure in the range between 300 bar and 900 bar for diesel engine fueled by B20 (20% Azolla +80% diesel) blend. The experimental engine study revealed that the physical properties of the fuel adversely affect the in-cylinder combustion, which leads to poor engine performance and higher emissions at lower injection pressure (300 bar) for B20 when compared to diesel. As the injection pressure increases, the fuel atomization and other spray characteristics are enhanced and thereby improve the combustion. The Brake Thermal Efficiency (BTE) for B20 at 900 bar injection pressure is 3% higher than the diesel fuel at 300 bar injection pressure under full load conditions. The HC, CO, and smoke emission in the engine exhaust for B20 at 900 bar injection pressure was reduced by 13.3%, 28.5%, and 12.3%, respectively, when compared to diesel. Overall, this study recommends the operation of Azolla biodiesel blend in diesel at 900 bar fuel injection pressure to attain improved engine characteristics.

GROUNDWATER AND DRINKING WATER RADON CONCENTRATIONS IN THE COASTAL AND INTERIOR AREAS OF CHENNAI METRO CITY AND ITS IMPACT ON PUBLIC HEALTH.

One hundred forty-eight water samples were collected from in and around Chennai and 222Rn concentrations were measured using radon emanometry method. The average 222Rn concentration was estimated to be 6.88, 2.01, 1.17, 0.19 and 0.10 Bq L-1 for borewell water, openwell water, tank water, metro water and lake water, respectively, which were within the U.S. Environmental Protection Agency's (USEPA) Standard limit of 11.1 Bq L-1 and World Health Organization (WHO) global average 10 Bq L-1. The total effective dose obtained has varied from 0 to 157.57 µSv y-1 with ±10% standard deviation. The mean values were 19.608, 8.092, 4.692, 0.761 and 0.423 µSv y-1 for closed borewell, open well water, tank water, metro water and for lake water, respectively. All these values were below the reference point 0.1 mSv y-1 (100 µSv y-1) set by WHO.

Maxillary brown tumor due to secondary hyperparathyroidism in a Hemodialysis patient: A case report and literature review.

Hemodialysis is one of the commonly used renal replacement therapies in treating end-stage renal failure patients. Patients with long-term dialysis may develop frequently complications such as secondary hyperparathyroidism (SHPT), bone diseases, amyloidosis, endocrinal disturbances, cardiovascular complications and infections. Brown tumors (BTs) are erosive giant cell bony lesions that arise in some patients as a result of primary or SHPT. About 2% of all the reported cases showed involvement of facial skeleton, of which the mandible is the favorite site. A complete clinical, biochemical, radiological and histopathological correlation is required for definitive diagnosis. We report here a case of BT in 37-year-old female hemodialysis patient with SHPT.

IMPACT OF THREE DIFFERENT MATCHING METHODS ON PATIENT SET-UP ERROR IN X-RAY VOLUMETRIC IMAGING FOR HEAD AND NECK CANCER.

Impact of three different matching methods for delivery of Volumetric Modulated Arc Therapy (VMAT) in Cone-beam computed tomography (CBCT) on patient set-up error. As per institutional imaging protocol, 300 CBCT scans of 20 VMAT head and neck cancer patients treated with 60 Gy/30 fractions were chosen for the present study. Approved CT images of the plan were registered as a reference with the CBCT images on board. Grey-scale matching (GM), manual matching (MM), and bone matching (BM) between on-board CBCT and reference CT images were used to assess patient translation errors. Patient positioning verification was evaluated using the Clip-box registration in all three matching methods. Using the GM approach as a reference point, two additional matchings were rendered in offline mode using BM and MM. For analysis, random error (σ), systematic error (∑), maximum error (E) mean set-up error (M), mean displacement vector (R), matching time (Mt), and multiple comparisons using Post hoc Tukey's HSD test were performed. In MM, less random and systematic errors were found than in GM and BM with an insignificant difference (p > 0.05) Compared to BM and GM, the maximum error, mean set-up error, and displacement vector were marginally less in MM (p > 0.05). In MM, an increased Mt relative to BM and GM was observed (p > 0.05). Furthermore, an insignificant difference in set-up error was revealed in a multiple comparison test (p > 0.05). Any of the three matching methods can be used during CBCT to check patient translation errors for the delivery of the VMAT head and neck patients.

Influence of pressure on the transport, magnetic, and structural properties of superconducting Cr0.0009NbSe2 single crystal.

We investigate the superconducting critical current density (J c), transition temperature (T c), and flux pinning properties under hydrostatic pressure (P) for Cr0.0009NbSe2 single crystal. The application of P enhances T c in both electrical resistivity (∼0.38 K GPa-1: 0 ≤ P ≤ 2.5 GPa) and magnetization (∼0.98 K GPa-1: 0 ≤ P ≤ 1 GPa) measurements, which leads to a monotonic increase in J c and flux pinning properties. The field-dependent J c at various temperatures under P is analyzed within the collecting pinning theory and it shows that δT c pinning is the crossover to δl pinning above the critical pressure (P c ∼0.3 GPa). Our systematic analysis of the flux pinning mechanism indicates that both the density of pinning centers and pinning forces greatly increase with the application of P, which leads to an enhancement in the vortex state. Structural studies using synchrotron X-ray diffraction under pressure illustrate a stable hexagonal phase without any significant impurity phase and lattice parameter reduction with P shows highly anisotropic nature.

Study to Compare the Effect of Different Registration Methods on Patient Setup Uncertainties in Cone-beam Computed Tomography during Volumetric Modulated Arc Therapy for Breast Cancer Patients.

PURPOSE: This study compared three different methods used in registering cone-beam computed tomography (CBCT) image set with planning CT image set for determining patient setup uncertainties during volumetric modulated arc therapy (VMAT) for breast cancer patients. MATERIALS AND METHODS: Seven breast cancer patients treated with 50 Gy in 25 fractions using VMAT technique were chosen for this study. A total of 105 CBCT scans were acquired by image guidance protocol for patient setup verification. Approved plans' CT images were used as the reference image sets for registration with their corresponding CBCT image sets. Setup errors in mediolateral, craniocaudal, and anteroposterior direction were determined using gray-scale matching between the reference CT images and onboard CBCT images. Patient setup verification was performed using clip-box registration (CBR) method during online imaging. Considering the CBR method as the reference, two more registrations were performed using mask registration (MR) method and dual registration (DR) (CBR + MR) method in the offline mode. For comparison, systematic error (∑), random error (σ), mean displacement vector (R), mean setup error (M), and registration time (R t) were analyzed. Post hoc Tukey's honest significant difference test was performed for multiple comparisons. RESULTS: Systematic and random errors were less in CBR as compared to MR and DR (P > 0.05). The mean displacement error and mean setup errors were less in CBR as compared to MR and DR (P > 0.05). Increased R t was observed in DR as compared to CBR and MR (P < 0.05). In addition, multiple comparisons did not show any significant difference in patient setup error (P > 0.05). CONCLUSION: For breast VMAT plan delivery, all three registration methods show insignificant variation in patient setup error. One can use any of the three registration methods for patient setup verification.

Assessing Prevalence of Temporomandibular Disorders among University Students: A Questionnaire Study.

AIM: The aim of this study is to assess the prevalence of temporomandibular disorders (TMDs) among university students. OBJECTIVES: The etiology of TMD is of multifactorial, and our study is designed to assess the prevalence of TMD in an institution within a university. Various parameters including trauma, malocclusion, stress assessment - its correlation with the timing, the duration of TMD in meeting the deadlines, and examinations have been assessed. MATERIALS AND METHODS: A standard questionnaire-based study with modified Fonseca anamnestic index is used. The questionnaire study was conducted with a statistically calculated sample size of 402 students within a university. The data were analyzed statistically for significance and correlations. Statistical analysis was performed using SPSS for Windows release 14.0 (SPSS Inc., Chicago, IL, USA). Differences at the 5% level were accepted as being statistically significant. RESULTS: TMD and its associated symptoms are frequent among students of health and science studies. Female predominance is seen. There was also an increased prevalence of symptoms in people who described themselves as being tense. The relationship between orthodontic therapy and TMDs were also evaluated, and the duration of therapy is found to be significant. There was a significant association between history of trauma and presence of TMDs. CONCLUSIONS: TMD and its associated symptoms are frequent among students of health and science studies. A simple anamnestic index is of use in identifying and classifying temporomandibular joint and TMD symptoms in patients according to the severity of the disorder. Females showed a greater prevalence of signs and symptoms of TMD than males. Longitudinal studies are recommended to identify and follow-up the prevalence and health-care needs of patients with TMDs.

Comparative study on attitudes and psychological problems of mothers towards their children with developmental disability.

OBJECTIVE: Parents' positive attitudes and psychological wellbeing play an important role in the development of the children with developmental disability. This study aimed to measure the prevalence of psychological problems among mothers of children with autism disorder, intellectual disability, and Down syndrome. The second aim was to assess the differences in mothers' attitudes and psychological problems among their children with intellectual disability, autism disorder, and Down syndrome. The third aim was to identify whether negative attitude was a predictor of psychological problems in these mothers. METHODS: In this study, 112 mothers of children having mild and moderate levels of autism disorder, Down syndrome, and intellectual disability were assessed using the Parental Attitude Scale and General Health Questionnaire-28. RESULTS: Overall, mothers of children with intellectual disability were found to have the most negative attitude towards their child. Mothers of children with autism disorder exhibited higher scores on somatic symptoms, anxiety, and social dysfunction when compared with their counterparts with Down syndrome and intellectual disability. Negative attitude was a significant predictor of psychological problems. CONCLUSION: Parental attitudes and psychological problems would vary among mothers of children with different types of developmental disability.

Osteopetrosis of the mandible masquerading as tubercular osteomyelitis.

Osteopetrosis is a rare congenital (autosomal type) disorder of the skeletal system. Several variants have been described in the literature with grossly variant prognosis and clinical behaviour. Several reports of intractable osteomyelitis of the jaw bones secondary to osteopetrosis, particularly the mandible, have been published widely. However, there is no published report of the complete mandible sequestrating de novo, in the literature. An overview of this spectrum of sclerotic bone disease, its presentation in the oro-facial region, the diagnostic challenge it poses and the management dilemma it offers to the maxillofacial surgeon is discussed and a protocol for managing this disease effectively is presented. A clinical illustration of the complexities of management of osteopetrosis-induced osteomyelitis of jaw bones is demonstrated with a very rare case in which the entire mandible had sequestrated.

Bioactive diopside (CaMgSi(2)O(6)) as a drug delivery carrier - a review.

The bone infections are the most divesting complications confronted by the physicians and patients. The antibiotic loaded bone cements, such as synthetic ceramics and natural ceramics were accepted for bone infections. The currently available bone cements were not accepted due to the lack of mechanical strength, porosity and quick degradation rate etc. The major aim of this review is to discuss about several different synthetic methods used to prepare the bioactive diopside (CaMgSi(2)O(6)) and its applications in ceramic drug delivery systems for controlled and targeted delivery. It has been reported from various research articles, diopside was mainly used for bone tissue regeneration, dentistry, orthopedics and enzyme delivery matrices with different formulations. Compared to other bioceramics diopside is preferable due to its biocompatibility and high mechanical strength.

Histamine H4 receptor: a novel target for inflammation therapy.

Histamine, a low molecular weight amine has been extensively studied for its various pharmacological profiles. Until recently histamine was thought to act on three receptors - H1, H2 and H3. Merely a decade back, sequencing of human genome has revealed a new histamine receptor - H4 receptor. This 390 amino acid sequenced receptor has around 38% homology with histamine H3 receptor besides; the pharmacological profile of the protein is quite different from other histamine receptors. H4 receptor is mainly expressed in mast cells and leukocytes and involves various physiological functions related to inflammation and allergy. Potent selective H4 receptor agonists and antagonists have been synthesized and in vivo studies have indicated their action on H4 receptor. In this review, structure, expression, homology sequence of H4 receptor among the different species has been documented. Further, structure activity relationship (SAR) of H4 ligands on the basis of their nucleus has been discussed in depth. In addition, anti-inflammatory effects of H4 receptor antagonists, with special emphasis to JNJ7777120, a selective H4 receptor antagonist have been focused exhaustively.