Avoiding space robot collisions utilizing the NASA/GSFC tri-mode skin sensor

A capacitance based proximity sensor, the 'Capaciflector' (Vranish 92), has been developed at the Goddard Space Flight Center of NASA. We had investigated the use of this sensor for avoiding and maneuvering around unexpected objects (Mahalingam 92). The approach developed there would help in executing collision-free gross motions. Another important aspect of robot motion planning is fine motion planning. Let us classify manipulator robot motion planning into two groups at the task level: gross motion planning and fine motion planning. We use the term 'gross planning' where the major degrees of freedom of the robot execute large motions, for example, the motion of a robot in a pick and place type operation. We use the term 'fine motion' to indicate motions of the robot where the large dofs do not move much, and move far less than the mirror dofs, such as in inserting a peg in a hole. In this report we describe our experiments and experiences in this area

Nucleotide-dependent DNA gripping and an end-clamp mechanism regulate the bacteriophage T4 viral packaging motor.

ATP-powered viral packaging motors are among the most powerful biomotors known. Motor subunits arranged in a ring repeatedly grip and translocate the DNA to package viral genomes into capsids. Here, we use single DNA manipulation and rapid solution exchange to quantify how nucleotide binding regulates interactions between the bacteriophage T4 motor and DNA substrate. With no nucleotides, there is virtually no gripping and rapid slipping occurs with only minimal friction resisting. In contrast, binding of an ATP analog engages nearly continuous gripping. Occasional slips occur due to dissociation of the analog from a gripping motor subunit, or force-induced rupture of grip, but multiple other analog-bound subunits exert high friction that limits slipping. ADP induces comparably infrequent gripping and variable friction. Independent of nucleotides, slipping arrests when the end of the DNA is about to exit the capsid. This end-clamp mechanism increases the efficiency of packaging by making it essentially irreversible

State of the Art Review on Prescriptive & Performance Based Approaches for Concrete Durability

Durability is a crucial and important requirement for concrete structures.  A durable concrete not only leads to sustainability but serve for longer period of time without much repair and maintenance.  The Concrete has been studied under various exposure conditions as stated in relevant standards but no significant attention is given for the in service performance of the concrete. In the last few decades, many researchers investigated the causes of structures deterioration and suggested various solutions to tackle the durability issues which are mainly adopting of performance-based specifications rather than prescriptive. In this paper, the previous findings on concrete durability are reviewed. The studies on the durability problems are highlighted along with prescriptive and performance-based approaches and test methods.  The effects on service life of the structures along with the solution are reviewed

Effectiveness of structured teaching programme on knowledge about postnatal care among mothers

Background: Mothers and new-borns are vulnerable to illness and deaths during the postnatal period. Care during postnatal period is the important part of maternal health care as the serious and life-threatening complications can occur in postnatal period.Methods: A Quantitative approach with pre- experimental design was used to study the effectiveness of STP on postnatal care. Sixty postnatal mothers were selected from tertiary care hospital. The Purposive sampling techniques was used to select the study subjects. Data was collected by using Structured Knowledge questionnaire.Results: The results show that the overall mean pre-test knowledge score of postnatal mothers was 19.8±2.98 and mean post-test knowledge score of postnatal mothers was 26.28±1.89 and the mean difference was 6.48. This revealed that the STP was an effective method in improving mother’s knowledge on postnatal care. There was no significant association found between pre-test knowledge score with their demographic variables except occupation.Conclusions: The findings of the study revealed that STP was effective in enhancing the knowledge of postnatal mothers on postnatal care

Structured teaching programme on knowledge about polycystic ovarian syndrome among adolescent girls

Background: Polycystic ovarian syndrome is a common female endocrine disorder affecting 4 – 18% of women in their reproductive age. It is common in adolescent girls. Polycystic Ovarian Syndrome affects throughout the life and produce gynaecological and metabolic health problems. The aim of this study to create the awareness about the polycystic ovarian syndrome to the adolescent girls.Methods: A Quantitative approach with pre- experimental design was used to study the effectiveness of STP on Poly Cystic Ovarian Syndrome. Ninety-four adolescent girls aged between 15 – 18 years were conveniently selected. Data was collected by using Structured Knowledge questionnaire.Results: The mean post-test knowledge score (22.55± 3.57) was higher than that of mean pre-test mean knowledge score (11.13± 3.32) and the mean difference was11.42. The ‘t’ calculated value was 23.45 which is higher than the tabulated value of 1.98 (df 93 at p< 0.05). Therefore, research hypothesis was accepted. So, it can be interpreting that structured teaching programme is effective in improving the knowledge of adolescent girls.Conclusions: The findings of the study revealed that STP was effective in enhancing the knowledge of adolescent girls on PCOS. Hence the study concluded that structured teaching programme had a great potentiality to increase the awareness on PCOS

Electrodeposition of Sn, Se, SnSe and the material properties of SnSe films

Tin sulphide (SnS) films have been electrodeposited and the materials properties are reported, The potential-pH diagram of Sn and S in aqueous medium are superimposed to obtain the common immunity domains which predicts a pH value 1.5 and deposition potential of ·1.0 VseE for the stoichiometric deposition. Films are cathodically deposited on 5002 coated conducting glass substrates at bath temperatures 303-353 K. XRD studies show the polycrystalline nature with orthorhombic structure. The optical band gap of the snS film is 1.1 eV from the absorption studies. ESCA spectrum confirms the presence of Sn and S on the grey black sample. Uniform, smooth and pin hole free surface morphology is observed by SEM

Respiratory syncytial virus infection in children less than five years of age presenting as severe community-acquired pneumonia

Background: Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infection in young children in both the community and hospital setting. Ongoing surveillance of the clinical and molecular epidemiology of RSV genotypes is important to characterize prevalent and emerging genotypes that may have impact on vaccine development. Objective: To assess the epidemiology of RSV infection in children &lt;5 years of age in a tertiary care hospital. Materials and Methods: Children &lt;5 years of age hospitalized with severe community-acquired pneumonia (CAP) were included in the study. Nasopharyngeal aspirate was taken for RSV reverse-transcriptase polymerase chain reaction. Results: A total of 100 children were recruited in the study. clinicoepidemiological epidemiological and radiological features were analyzed. The prevalence of RSV infection in children &lt;60 months of age admitted with the features of severe pneumonia in our study was 30% with almost equal proportion of RSV A and B groups. Underlying congenital heart disease and family history of asthma were identified as significant risk factors. There were no significant clinical and radiological features to distinguish RSV from non-RSV disease. Conclusions: This study highlights the relevance of RSV infection in hospitalized cases of CAP in our region. Our findings warrant the conduct of further investigations which can help design strategies for controlling the disease. If RT-PCR could be used in children with severe pneumonia who are hospitalized, an accurate diagnosis of RSV bronchiolitis can be made in high percentage of children

YALE OBSERVATION SCALE AS A PREDICTOR OF BACTEREMIA AND FINAL OUTCOME IN 3-36 MONTHS OLD FEBRILE CHILDREN ADMITTED IN TERTIARY HEALTH CENTRES: A HOSPITAL-BASED CROSS-SECTIONAL STUDY

ABSTRACTObjectives: The objective of the study was to assess predictability of bacteremia in febrile children in the age group of 3-36 months by application ofYale observation scale (YOS) and to predict clinical course during hospital stay and final outcome by YOS.Methods: A hospital-based cross-sectional study was carried out at Kasturba Medical College, Mangalore, Karnataka, for a period of 2 years(September 2013-September, 2015) in 100 febrile children in the age group of 3-36 months with probable infectious etiology admitted in ward/PICU.Children with any non-infectious causes of fever (vaccination, autoimmune, and immunodeficiency disorder) were excluded from the study. Caseswere selected by simple random sampling. The primary study outcome was bacteremia based on positivity on blood culture and sensitivity sampledrawn at admission. Secondary outcomes are clinical course in the hospital, use of antibiotics, need for mechanical ventilation, hospital stay, andmortality.Results: 100 cases were included in the study out of which 18 cases were bacteremic with a mean YOS of 26 (non-bacteremic - 11), mean hospitalstay 19.5 days (non-bacteremic - 12 days). All 18 bacteremic children had YOS ≥20, but YOS ≥20 had 8 false positives cases. There was no significantinterobserver variability in YOS assessment (Cronbach's alpha - 0.993 showing good correlation with intraclass correlation coefficient - 0.986).Higher YOS scores had good sensitivity, specificity, positive and negative likelihood ratios, and area under curve for prediction of bacteremia atYOS &gt;20 (100%, 90.2%, 10.2, 0.00, and 0.970), need for mechanical ventilation at YOS &gt;21 (100%, 91.7%, 12.04, 0.00, and 0.969), need for scaling upantibiotics at YOS &gt;21 (70.4%, 94.4%, 12.5, 0.31, and 0.822), and mortality at YOS &gt;21 (90.9%, 85.4%, 6.2, 0.106, 0.878).Conclusion: YOS is a good tool to rule out bacteremia and to prognosticate the clinical course at the first visit. This simple scale can be of value inmonitoring admitted patients for deteriorating clinical state and for assessing the need for referral to higher centers for further management.Keywords: Yale observation scale, Bacteremia, Febrile patients

Highly Stretchable and Highly Resilient Polymer-Clay Nanocomposite Hydrogels with Low Hysteresis

Highly stretchable and highly resilient polymer-clay nanocomposite hydrogels were synthesized by in situ polymerization of acrylamide in the presence of pristine montmorillonite (MMT) or chitosan-treated MMT nanoplatelets at an elevated temperature. Both nanocomposite hydrogels can be stretched to a strain of no less than 1290%. The treatment of clay with chitosan improves the tensile strength, elongation at break, and energy at break of the nanocomposite hydrogel by 237%, 102%, and 389%, respectively, due to the strong chitosan-MMT electrostatic interaction and the grafting of polyacrylamide onto chitosan chains. Both hydrogels display excellent resilience with low hysteresis; with a maximum tensile strain of 50%, ultralow hysteresis is found, while, with a maximum strain of 500%, both hydrogels fully recover their original state in just 1 min. The superb resilience of the nanocomposite hydrogels is attributed to the strong interactions within the hydrogels brought by chain branching, multiple hydrogen bonding, covalent bonding, and/or electrostatic force. The hydrogels can be fabricated into different shapes and forms, including microfibers spun using pressurized gyration, which may find a variety of potential applications in particular in healthcare

Identification and characterization of a Ross River virus variant that grows persistently in macrophages, shows altered disease kinetics in a mouse model, and exhibits resistance to type I interferon

Alphaviruses, such as chikungunya virus, o'nyong-nyong virus, and Ross River virus (RRV), cause outbreaks of human rheumatic disease worldwide. RRV is a positive-sense single-stranded RNA virus endemic to Australia and Papua New Guinea. In this study, we sought to establish an in vitro model of RRV evolution in response to cellular antiviral defense mechanisms. RRV was able to establish persistent infection in activated macrophages, and a small-plaque variant (RRVPERS) was isolated after several weeks of culture. Nucleotide sequence analysis of RRV PERS found several nucleotide differences in the nonstructural protein (nsP) region of the RRV PERS genome. A point mutation was also detected in the E2 gene. Compared to the parent virus (RRV-T48), RRV PERS showed significantly enhanced resistance to beta interferon (IFN-β)-stimulated antiviral activity. RRV PERS infection of RAW 264.7 macrophages induced lower levels of IFN-β expression and production than infection with RRV-T48. RRV PERS was also able to inhibit type I IFN signaling. Mice infected with RRV PERS exhibited significantly enhanced disease severity and mortality compared to mice infected with RRV-T48. These results provide strong evidence that the cellular antiviral response can direct selective pressure for viral sequence evolution that impacts on virus fitness and sensitivity to alpha/beta IFN (IFN-α/β).Facultad de Ciencias Exacta