Development of New Space Systems Architecture in SYSML Using Model-Based Pattern Language

This manuscript presents an approach to the application of the Model-Based Systems Engineering (MBSE) and Model-Based Systems Architecting (MBSA) principles to develop a Model-Based Pattern Language (MBPL). It takes considerable time for systems engineers and mission architects to develop a new system from scratch, particularly new space-based systems derived from the existing space system architectures. The use of a pattern language which is a holistic view of reusable logical model artifacts, can improve the process. The main benefit of the pattern language is to reduce the time and validation required to generate a new space-based system architecture; this approach will develop top-level requirements in the initial phase of the system development. The approach of the methodology in this research was to collect and decompose published literature and other open-source information available on space system architectures and system models. After those were generated, SysML models for systems, sub-systems, products, assembly, subassembly level, and mission-specific requirements were derived from the existing systems and documents using CAMEO SysML software. These patterns were then arranged into a functional ontology and used to construct a logical architecture pattern library. This approach created, updated, and managed a SysML pattern language, which expedited new model construction. The goal was to develop a logical pattern language using public domain information and evaluate patterns by constructing a new space mission. This research was partly funded by the NASA Advanced Concepts Office (ACO) Huntsville, AL., during 2021

Extended reverse sural artery pedicle flap: a versatile and reproducible option for coverage of ankle and foot defects

Background: Coverage of soft tissue defects around distal third of the leg, particularly ankle and foot is a common situation faced by a plastic and reconstructive surgeon. Options available for such defects are limited due to scarcity of additional soft tissue that can be used without exposing tendons or bone. Associated conditions such as major vascular compromise, comorbidities and lack of facilities or expertise make free tissue transfer less preferred. Distally based sural artery flap has been a frequently used flap in such conditions, easy to perform and has reproducible results. We extended the reach of the flap and reproduced the results.Methods: We performed extended reverse sural artery pedicled flaps in 19 patients who presented to us between 2015 to 2017 with soft tissue defects around ankle and foot. Patients included 15 post RTA, 2 diabetic foot, 1 post resection defect and 1 post burn contracture release defect. Size of the defect ranged between 8x6cm to 14x10cm. Average follow up period was ranging from 8 months to 2.5 years.Results: All the flaps healed well without any obvious complications except one patient in whom marginal necrosis (2 cm margin of distal most flap) was observed and was secondarily treated with skin grafting.Conclusions: We observed that extended reverse sural pedicle flap is a rapid, reliable option for coverage of soft tissue defects around ankle and heel, sparing major vessel compromise and lengthy surgical procedure during free tissue transfer. This flap should be the first option for the patients with trauma and defects over weight bearing foot in whom peroneal axis vessels are preserved

Rejection Sensitivity, Perceived Power, and HIV Risk in the Relationships of Low-Income Urban Women

The psychological processes associated with HIV infection in long-term relationships differ from those operative in casual sexual encounters, and relatively little research has considered the aspects of personality applicable in the ongoing heterosexual relationships in which women are at greatest risk. Sensitivity to rejection has been linked with efforts to prevent rejection at a cost to the self and, therefore, may be relevant to the health risks that many women incur in relationships. We examined the association of rejection sensitivity with women\u27s sexual risk behavior in a sample of women at heightened risk for HIV exposure. Women in long-term heterosexual relationships (N = 159) were recruited for study participation in the hospital emergency room serving a low-income neighborhood in New York City, in 2001-2003. Rejection sensitivity and known HIV risk factors were assessed using verbally administered questionnaires. Rejection sensitivity was associated with lower perceived relationship power and, in turn, more frequent unprotected sex with a partner perceived to be at risk for HIV. These results held when controlling for other HIV risk factors including partner violence, economic dependence, and substance use. Understanding the association of rejection concerns with lower perceived personal power in relationships may be important for HIV prevention

SOLUBILITY AND DISSOLUTION ENHANCEMENT OF PIOGLITAZONE USING SOLID DISPERSION TECHNIQUE

Objective: To design the study to improve the solubility and hence enhance the dissolution of hydrophobic drug Pioglitazone in order to increase its bioavailability.Methods: Solid dispersion of Pioglitazone using carriers Poloxomer 188 and HPβCD was formulated in different ratios by microwave induced fusion method. In particular, the Microwave technology has been considered in order to prepare an enhanced release dosage form for poorly water soluble drug Pioglitazone. Statistical Analysis: Their physicochemical characteristics and solubility were compared to the corresponding dispersions and marketed drug. Drug and polymer were further characterized by FTIR.Results: The results of FTIR revealed that no chemical interaction between the drug and the polymer exist.Conclusion: All the formulations showed a marked increase in drug release with the increase in the concentration of Poloxomer 188 and HPβCD.Â