714 research outputs found

    A study of density modulation index in the inner heliospheric solar wind during solar cycle 23

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    The ratio of the rms electron density fluctuations to the background density in the solar wind (density modulation index, ϵN≡ΔN/N\epsilon_{N} \equiv \Delta{N}/N) is of vital importance in understanding several problems in heliospheric physics related to solar wind turbulence. In this paper, we have investigated the behavior of ϵN\epsilon_{N} in the inner-heliosphere from 0.26 to 0.82 AU. The density fluctuations ΔN\Delta{N} have been deduced using extensive ground-based observations of interplanetary scintillation (IPS) at 327 MHz, which probe spatial scales of a few hundred km. The background densities (NN) have been derived using near-Earth observations from the Advanced Composition Explorer (ACE\it{ACE}). Our analysis reveals that 0.001≲ϵN≲0.020.001 \lesssim \epsilon_{N} \lesssim 0.02 and does not vary appreciably with heliocentric distance. We also find that ϵN\epsilon_{N} declines by 8% from 1998 to 2008. We discuss the impact of these findings on problems ranging from our understanding of Forbush decreases to the behavior of the solar wind dynamic pressure over the recent peculiar solar minimum at the end of cycle 23..Comment: 13 Pages, 8 Figures, Accepted for publication in Ap

    Staging resection and reconstruction with temporary wound VAC coverage in a case of giant cystosarcoma phyllodes of the breast

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    AbstractIntroductionCystosarcoma phyllodes (CP) is a rare breast tumor occurring most often in females in their fifth decade. While usually benign, some CP tumors exhibit aggressive growth patterns and extensively invade chest wall structures; resecting these tumors to negative surgical margins can be challenging. We present a case of malignant CP involving the chest wall where using a negative pressure vacuum-assisted closure (VAC) system after resection enabled complete histopathologic margin assessment prior to reconstruction. This is the first known report of staged breast tumor resection and reconstruction with interim VAC coverage.Case presentationA 48 year-old woman presented with rapidly increasing left breast size, fevers, and fatigue. On examination, the left breast was massively enlarged with engorged vessels and skin necrosis. Lab analyses revealed unusual metabolic abnormalities requiring preoperative hospitalization. We performed a left modified radical mastectomy with partial resection of pectoralis major and minor muscles, temporarily sealing the wound with a VAC due to concern for deeper tumor extension that could require further resection. Pathology revealed malignant CP with a negative deep margin. The 38cm defect was then repaired with latissimus myocutaneous flap plus skin graft. At three-year follow up the patient remains free of disease.ConclusionIn cases of malignant CP involving the chest wall, minimizing the extent of chest wall resection is critical for reducing morbidity, while completely clearing tumor margins is essential for reducing recurrence risk. Using temporary wound VAC coverage enables cautious debulking followed by histopathologic margin assessment prior to definitively reconstructing the breast

    Host preferences of some acridids (Insecta: Orthoptera) in relation to some biochemical parameters

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    Biochemical analysis of host plants of 6 species of acridids for their total protein, carbohydrates, phenols, free aminoacids, water and nitrogen content revealed significant correlation in regard to their host preferences, wherein the leaf water-nitrogen index as well as the total phenol composition appeared to play an important role

    Giant Meterwave Radio Telescope observations of an M2.8 flare: insights into the initiation of a flare-coronal mass ejection event

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    We present the first observations of a solar flare with the GMRT. An M2.8 flare observed at 1060 MHz with the GMRT on Nov 17 2001 was associated with a prominence eruption observed at 17 GHz by the Nobeyama radioheliograph and the initiation of a fast partial halo CME observed with the LASCO C2 coronograph. Towards the start of the eruption, we find evidence for reconnection above the prominence. Subsequently, we find evidence for rapid growth of a vertical current sheet below the erupting arcade, which is accompanied by the flare and prominence eruption.Comment: Accepted for publication in Solar Physic

    Effect of Seams on Drape of Fabrics

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    Drape of the fabric is its ability to hang freely in graceful folds when some area of it is supported over a surface and the rest is unsupported. Drape is a unique property that allows a fabric to be bent in more than in one direction, When two-dimensional fabric are converted to three-dimensional garment form. In the present study, the effects of sewing of different seam were selected on different fabric and their behaviors were studied. In this study drape of ten fabrics are analyzed with three types of seams and three stitch densities. Sample without seam is a control sample and drape of seamed samples are compared with control sample to analyse the drape behavior of seamed fabrics. This paper presents a fundamental drape analysis of seamed fabrics using drape meter. Drape behavior is determined in terms of drape coefficient. The effect of seams on the drape coefficient and Drape profile has been made. Drape coefficients significantly differs between the fabrics and also between the seam stitch density combinations. Investigating drape onseamed fabrics can improve fabric end use application. Key words: drape, computer aided design, seam, stitch density, Design of Experiment

    The dynamics and control of large flexible space structures, 8

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    A development of the in plane open loop rotational equations of motion for the proposed Spacecraft Control Laboratory Experiment (SCOLE) in orbit configuration is presented based on an Eulerian formulation. The mast is considered to be a flexible beam connected to the (rigid) shuttle and the reflector. Frequencies and mode shapes are obtained for the mast vibrational appendage modes (assumed to be decoupled) for different boundary conditions based on continuum approaches and also preliminary results are obtained using a finite element representation of the mast reflector system. The linearized rotational in plane equation is characterized by periodic coefficients and open loop system stability can be examined with an application of the Floquet theorem. Numerical results are presented to illustrate the potential instability associated with actuator time delays even for delays which represent only a small fraction of the natural period of oscillation of the modes contained in the open loop model of the system. When plant and measurement noise effects are added to the previously designed deterministic model of the hoop column system, it is seen that both the system transient and steady state performance are degraded. Mission requirements can be satisfied by appropriate assignment of cost function weighting elements and changes in the ratio of plant noise to measurement noise

    Prevalence and Molecular Characterisation of Circulating Serotypes of Rotavirus in Children less than 5 Years Old with Acute Watery Diarrhoea Attending Paediatric Department in a Tertiary Care Hospital

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    INTRODUCTION : Diarrheal diseases are one of the major reasons of illness and death in smaller children globally, particularly in less developed countries. Diarrhoea, especially acute watery diarrhoea, always a most important public health problem in all parts of the world. WHO estimated an attack rate of 3.2 episodes of diarrhoea per child every year globally. Diarrheal diseases result in about 2 million deaths every year, which makes it third among all causes of infectious disease deaths worldwide. Though global deaths from childhood diarrhoea decreased during the past 2 decades, there has been an increase in the number of hospitalizations due to diarrhoea. The decrease in diarrhoeal deaths may largely be attributed to the oral rehydration therapy, which has been reported to prevent 3 million dehydration deaths in a year globally. AIMS AND OBJECTIVES : 1. To estimate the prevalence of rota virus in smaller Children less than 5years of age attending paediatric department (Outpatient and In-patient) of Chengalpattu Medical College Hospital with acute watery diarrhoea 2. To find out the circulating serotypes of rotavirus in the confirmed cases 3. To do molecular characterisation of Rotavirus MATERIALS AND METHODS : Design of The Study: Cross sectional study Study Period: MAY 2015 TO APRIL 2016 Place of Study: Department of Microbiology, Chengalpattu Medical College, Chengalpattu Department of Paediatrics, Chengalpattu Medical College Hospital, Chengalpattu. King Institute of Preventive Medicine and Research Centre, Guindy, Chennai Selection Of Study Group: A total of 105 children, 0-5 years of age were included in the study. The clinical and demographic profiles obtained after obtaining proper consent from the parents / guardians. Inclusion Criteria : Children less than 5 years of age with complaints of more than three episodes of watery stools passed devoid of mucus and blood for a duration of less than 2 weeks and not on antibiotics or any laxatives were counted for this study. Exclusion Criteria : Children above 5 years of age Children with complaints of diarrhoea more than 2 weeks Children who had Rotavirus vaccine Children who acquired diarrhoeal illness after hospital admission were excluded from the study. Ethical Consideration : Ethical and research clearance was obtained from the Institutional Ethics Committee, Chengalpattu Medical College. Permission to conduct the study was sought from the Department of Paediatrics. Parents / guardians were enlightened about importance of the study and then consent was obtained from them before their child being incorporated into the study. Statistical Analysis : The statistical procedures were performed by the statistical package PASW (Predictive and Analysis Software) statistics -18 so called SPSS. The p values less than 0.05 were considered as significant. Collection and Transport of Stool Samples: The stool samples were collected in a clean wide mouthed sterile container, labelled properly, transported to the laboratory in ice pack for further processing. Samples were transported to The King Institute of Preventive Medicine, Guindy, Chennai, for PCR and further analysis. Throughout the transport and during preservation meticulous care was taken to ensure the cold chain of sample. Microbiological Analysis : A portion of each sample was stored in screw capped vials at -70ºc for analysis of Rota virus. Detection and Characterization of Rota Virus: Detection of Rota virus: All stool samples collected were subjected to Rotavirus identification tests with commercially available ELISA kit detecting group specific VP6 antigen for rota virus. 1. Antigen detection: was done by Enzyme Linked Immunosorbent assay method (ELISA) according to manufacturer’s instruction. [ROTACLONE] 2. Molecular characterisation and genotyping by conventional multiplex PCR. RESULTS : In this study 105 stool samples were collected from smaller children of less than 5 years of age, suffering from acute watery diarrhoea. And those are attending the paediatric Out-patient department or admitted for care as In-patients in Govt. Chengalpattu Medical College and Hospital. Rota virus antigen detection was done for all samples by ELISA. Out of 105 stool samples 24 showed positive results. Reverse Transcriptase Polymerase Chain Reaction was done for all the 24 ELISA positive samples for determination of G and P genotype of the rota virus stains. SUMMARY : This study was conducted at the Department of Microbiology; Chengalpattu Medical College and Hospital aimed at detection of Rotavirus in children with acute watery diarrhoea and Sero-tying. • Stools samples collected from 105 children with acute watery diarrhea were included in this study. • The samples were subjected to rotavirus antigen detection by VP6 specific monoclonal antibodies in Antigen Capture Enzyme Linked Immunosorbent Assay. • The samples which were positive for rotavirus were subjected to Reverse transcriptase polymerase chain reaction for characterisation of the rotavirus strains. • In the present study, most of the children with acute watery diarrhoea were in the age group 0-1 year, 55.23%, followed by 1-2 years, 30.47%. • Rotavirus prevalence was found to be 22.86% among children attending tertiary care hospital which was significantly associated with diarrhoea. • The main clinical presentation of rotavirus infected patients was acute watery diarrhoea associated with vomiting in 87.5% followed by fever in 79.17%. • Among ELISA positive cases 15 were found to be positive by RT-PCR. • 40% of the Rotavirus strains were fully typed for G and P Genotypes. 40% were partially typed and 20% were not typeable. • 80% of the G – Genotype and 40% of the P – Genotype could be determined. G9 Genotype was identified as predominant in G type, P[4] was identified as predominant P type. CONCLUSION : In the present study rotavirus was detected in 24 cases out of 105 children presented with acute watery diarrhoea. • Rotavirus prevalence was found to be 22.86% among children under 5 year of age with acute watery diarrhoea. • Majority of them were in the age group of 0-2 years. • The Genotype combinations of rotavirus identified is G9P[4], Partially typed – either G or P and GP both untypeable. • Thus the present study shows significant association of rotavirus in children under five years of age with acute watery diarrhoea and the prevalence of Serotype G9P4.The predominant rota virus strain in circulation appears to be G9P[4] in the study population, which is not a component of vaccines available at present. But the non typeable strains also pose an unknown antigenic challenge to the susceptible population. • Early diagnosis of Rotavirus in acute watery diarrhoea, continuous surveillance and prospective monitoring of its circulating strains and serotypes in any geographical area are important in public health perspective. It minimises the hospitalisation and mortality in children of under 5 age group. Any indiscriminate usage of antimicrobials in viral diarrhoea should be avoided and ORS should be encouraged. Effective vaccination prevents the disease burden and severity of Rotavirus in the community
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