Sequencing of parts and robot moves in a robotic cell

In this paper, we deal with the problem of sequencing parts and robot moves in a robotic cell where the robot is used to feed machines in the cell. The robotic cell, which produces a set of parts of the same or different types, is a flow-line manufacturing system. Our objective is to maximize the long-run average throughput of the system subject to the constraint that the parts are to be produced in proportion of their demand. The cycle time formulas are developed and analyzed for this purpose for cells producing a single part type using two or three machines. A state space approach is used to address the problem. Both necessary and sufficient conditions are obtained for various cycles to be optimal. Finally, in the case of many part types, the problem of scheduling parts for a specific sequence of robot moves in a two machine cell is formulated as a solvable case of the traveling salesman problem.     

Topographical localization of distinct antigenic domains of Toxoplasma gondii with the aid of monoclonal antibodies

In the present study, a panel of six individual hybridoma derived antibodies produced against the BK strain of Toxoplasma gondii were evaluated for their reactivity in an immunofluorescence test. Each of the six monoclonal antibodies demonstrated a unique pattern of fluorescence localized to distinctive regions on the toxoplasmas. Although all of the six detected antigenic determinants which were shared by at least four different T. gondii strains, monoclonal antibody TG-E4A17 has disclosed hitherto unrecognized population differences among the BK or PH strain parasites. The fact that some of the antigenic molecules are restricted to distinct regions of the toxoplasmas may have implications in the infections process/immune response.     

Utility of nuclear stress imaging for detecting coronary artery bypass graft disease

ABSTRACT: BACKGROUND: The value of Single Photon Emission Computed Tomography stress myocardial perfusion imaging (SPECT-MPI) for detecting graft disease after coronary artery bypass surgery (CABG) has not been studied prospectively in an unselected cohort. METHODS: Radial Artery Versus Saphenous Vein Graft Study is a Veterans Affairs Cooperative Study to determine graft patency rates after CABG surgery. Seventy-nine participants agreed to SPECT-MPI within 24 hours of their coronary angiogram, one-year after CABG. The choice of the stress protocol was made at the discretion of the nuclear radiologist and was either a symptom-limited exercise test (n=68) or an adenosine infusion (n=11). The SPECT-MPI results were interpreted independent of the angiographic results and estimates of sensitivity, specificity and accuracy were based on the prediction of a graft stenosis of [greater than or equal to]70% on coronary angiogram. RESULTS: A significant stenosis was present in 38 (48%) of 79 patients and 56 (22%) of 251 grafts. In those stress tests with an optimal exercise heart rate response (>80% maximum predicted heart rate) (n=26) sensitivity, specificity and accuracy of SPECT-MPI for predicting the graft stenosis was 77%, 69% and 73% respectively. With adenosine (n=11) it was 75%, 57% and 64%, respectively. Among participants with a suboptimal exercise heart rate response, the sensitivity of SPECT-MPI for predicting a graft stenosis was <50%. The accuracy of SPECTMPI for detecting graft disease did not vary significantly with ischemic territory. CONCLUSIONS: Under optimal stress conditions, SPECT-MPI has a good sensitivity and accuracy for detecting graft disease in an unselected patient population 1 year post-CABG.     

A comparative study of semi-squaraine and squaraine dyes using computational techniques: tuning the charge transfer/biradicaloid character by substitution

Semi-squaraines (SMSQ) are known as donor-acceptor (D-A) type molecules whereas squaraines (SQ), which differs from SMSQ by an extra donor group, are more or less biradicaloids in nature. The effect of the additional donor group in SQ, which changes the nature of the molecule, on geometrical and electronic structure are studied here and compared with the corresponding SMSQ. It is noticed from the geometrical parameters that, a strong resonance exists in SQ whereas disparity in carbon-carbon bond lengths of central C₄ ring is seen in SMSQ dyes. The increasing and decreasing of antibonding interactions between central C₄ ring and side donor groups cause destabilization of HOMO and stabilization of LUMO respectively in case of SQ compared to SMSQ molecules. This leads to decreasing the HOMO-LUMO gap and promotes biradicaloid character of SQ. The absorption maxima obtained by using TD-DFT method with BLYP, B3LYP, BHandHLYP, CAM-B3LYP and M06-2X functionals are not in good agreement with experimental results. On the other hand SAC-CI method gives better results for all the molecules. From this work we can evolve a design principle of these molecules which play a role as sensitizers in dye sensitized solar cells.     

Efficacy of live attenuated and inactivated influenza vaccines among children in rural India: A 2-year,randomized, triple-blind,placebo-controlled trial

BackgroundInfluenza is a cause of febrile acute respiratory infection (FARI) in India; however, few influenza vaccine trials have been conducted in India. We assessed absolute and relative efficacy of live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV) among children aged 2 to 10 years in rural India through a randomized, triple-blind, placebo-controlled trial conducted over 2 years.Methods and findingsIn June 2015, children were randomly allocated to LAIV, IIV, intranasal placebo, or inactivated polio vaccine (IPV) in a 2:2:1:1 ratio. In June 2016, vaccination was repeated per original allocation. Overall, 3,041 children received LAIV (n = 1,015), IIV (n = 1,010), nasal placebo (n = 507), or IPV (n = 509). Mean age of children was 6.5 years with 20% aged 9 to 10 years.Through weekly home visits, nasal and throat swabs were collected from children with FARI and tested for influenza virus by polymerase chain reaction. The primary outcome was laboratory-confirmed influenza-associated FARI; vaccine efficacy (VE) was calculated using modified intention-to-treat (mITT) analysis by Cox proportional hazards model (PH) for each year.In Year 1, VE was 40.0% (95% confidence interval (CI) 25.2 to 51.9) for LAIV and 59.0% (95% CI 47.8 to 67.9) for IIV compared with controls; relative efficacy of LAIV compared with IIV was −46.2% (95% CI −88.9 to −13.1). In Year 2, VE was 51.9% (95% CI 42.0 to 60.1) for LAIV and 49.9% (95% CI 39.2 to 58.7) for IIV; relative efficacy of LAIV compared with IIV was 4.2% (95% CI −19.9 to 23.5). No serious adverse vaccine-attributable events were reported. Study limitations include differing dosage requirements for children between nasal and injectable vaccines (single dose of LAIV versus 2 doses of IIV) in Year 1 and the fact that immunogenicity studies were not conducted.ConclusionsIn this study, we found that LAIV and IIV vaccines were safe and moderately efficacious against influenza virus infection among Indian children.Trial registrationClinical Trials Registry of India CTRI/2015/06/005902.

Anand Krishnan and co-workers study the efficacy and safety of influenza vaccines for children in India.     

Electron microscope observations on the interaction of Mycoplasma fermentans with Trichomonas vaginalis

Cultures of Trichomonas vaginalis were found to be contaminated with Mycoplasma fermentans. By means of electron microscopy the interaction between the prokaryotic organisms and the trichomonads was examined. Cells of M. fermentans were observed in the medium; some of them were attached to the surface of the trichomonads and others were observed in membrane-bounded vacuoles of trichomonads. They were also present in the ground substance of the cytoplasm. The mycoplasmas divided by binary fission like other prokaryotes. The most obvious change occurring in the infected trichomonad cells was an increase in number of vacuoles containing mycoplasmas.     

Attempts to produce experimental intestinal cryptococcosis and sporotrichosis

Summary The technique used in this experiment for feeding infected material to hamsters led to the production of occasional primary pulmonary foci of cryptococcosis and sporotrichosis, respectively. No evidence of primary intestinal cryptococcosis or sporotrichosis was obtained.This study was supported in part by Grant E-576 from the National Institutes of Health.