165 research outputs found
Smoldering combustion of "Incense" sticks- experiments and modeling
This paper is concerned with the experimental and modeling studies on the smoldering rates of incense sticks as a function of ambient oxygen fraction in air, the flow velocity and size. The experimental results are obtained both for forward and reverse smolder conditions. The results are explained on the basis of surface combustion due to diffusion of oxygen to the surface by both free and forced convection supporting the heat transfer into the solid by conduction, into the stream by convection and the radiant heat transfer from the surface. The heat release at the surface is controlled by the convective transport of the oxidizer to the surface. To obtain the diffusion rates particularly for the reverse smolder, CFD calculations of fluid flow with along with a passive scalar are needed; these calculations have been made both for forward and reverse smolder. The interesting aspect of the CFD calculations is that while the Nusselt umber for forward smolder shows a clear √Reu dependence (Reu = Flow Reynolds Number), the result for reverse smolder shows a peak in the variation with Reynolds number with the values lower than for forward smolder and unsteadiness in the flow beyond a certain flow rate. The results of flow behavior and Nusselt number are used in a simple model for the heat transfer at the smoldering surface to obtain the dependence of the smoldering rate on the diameter of the incense stick, the flow rate of air and the oxygen fraction. The results are presented in terms of a correlation for the non-dimensional smoldering rate with radiant flux from the surface and heat generation rate at the surface. The correlations appear reasonable for both forward and reverse smolder cases
6-[(DimethylÂamino)methylÂeneÂamino]-1,3-dimethylÂpyrimidine-2,4(1H,3H)-dione dihydrate
Uracil, the pyrimidine nucleobase, which combined with adenine forms one of the major motifs present in the biopolymer RNA, is also involved in the self-assembly of RNA. In the title compound, C9H14N4O2·2H2O, the asymmetric unit contains one dimethylÂaminoÂuracil group and two water molÂecules. The plane of the N=C—NMe2 side chain is inclined at 27.6 (5)° to the plane of the uracil ring. Both water molÂecules form O—H⋯O hydrogen bonds with the carbonyl O atoms of the uracil group. Additional water–water hydrogen-bond interÂactions are also observed in the crystal structure. The O—H⋯O hydrogen bonds lead to the formation of a two-dimensional hydrogen-bonded network cage consisting of two dimethylÂaminoÂuracil groups and six water molÂecules
6,6′-Diamino-1,1′,3,3′-tetraÂmethyl-5,5′-(4-chloroÂbenzylÂidene)bisÂ[pyrimidine-2,4(1H,3H)-dione]
The title compound, C19H21ClN6O4, is a 1:2 adduct of p-chloroÂbenzaldehyde and uracil. It crystallizes with two molÂecules in the asymmetric unit. The two uracil units in the same molÂecule are connected by a pair of strong N—H⋯O hydrogen bonds. The packing is stabilized by N—H⋯O, C—H⋯O and C—H⋯N interÂactions
An Adolescent with Progressive Enlargement of Digits: Case report and proposed diagnostic criteria for macrodystrophia lipomatosa
Macrodystrophia lipomatosa (ML) is a rare congenital non-hereditary condition caused by an increase in all mesenchymal elements. We report a 14-year-old girl who presented to the Medical Outpatient Department, Kunhitharuvai Memorial Charitable Trust Medical College, Kozhikode, India, in 2017 with progressive enlargement of digits. An X-ray and T1-weighted magnetic resonance imaging scan showed enlargement of the phalanges of the middle and index finger of the left hand with an overgrowth of soft tissues. The patient was subsequently diagnosed with ML. As the condition is benign and usually asymptomatic, no medical treatment was deemed necessary. This report describes a case of ML and proposes a set of diagnostic criteria to aid clinicians in the differential diagnosis of the condition.
Keywords: Congenital Disorders; Gigantism; Macrodactyly of the Hand; Differential Diagnosis; Case Report; India
Recombinant Filaggrin Is Internalized and Processed to Correct Filaggrin Deficiency
This study was designed to engineer a functional filaggrin (FLG) monomer linked to a cell-penetrating peptide (RMR) and to test the ability of this peptide to penetrate epidermal tissue as a therapeutic strategy for genetically determined atopic dermatitis (AD). A single repeat of the murine filaggrin gene (Flg) was covalently linked to a RMR motif and cloned into a bacterial expression system for protein production. Purified FLG+RMR (mFLG+RMR) was applied in vitro to HEK-293T cells and a reconstructed human epidermis (RHE) tissue model. Immunochemistry demonstrated RMR-dependent cellular uptake of FLG+RMR in a dose- and time-dependent manner in HEK cells. Immunohistochemical staining of the RHE model identified penetration of FLG+RMR to the stratum granulosum, the epidermal layer at which FLG deficiency is thought to be pathologically relevant. In vivo application of FLG+RMR to FLG-deficient flaky tail (ft/ft) mice skin demonstrated internalization and processing of recombinant FLG+RMR to restore the normal phenotype. These results suggest that topically applied RMR-linked FLG monomers are able to penetrate epidermal tissue, be internalized into the appropriate cell type, and be processed to a size similar to wild-type functional barrier peptides to restore necessary barrier function, and prove to be therapeutic for patients with AD
Secure Wireless Networks
This paper provides a brief overview of wireless (WiFi) networks and some of the security measures in place today. We further seek to find a secure way to authenticate and enable secure communication between wireless (WiFi) clients and external networks
Reverse Engineering of Computer-Based Navy Systems
The financial pressure to meet the need for change in computer-based systems through evolution rather than through revolution has spawned the discipline of reengineering. One driving factor of reengineering is that it is increasingly becoming the case that enhanced requirements placed on computer-based systems are overstressing the processing resources of the systems. Thus, the distribution of processing load over highly parallel and distributed hardware architectures has become part of the reengineering process for computer-based Navy systems.
This paper presents an intermediate representation (IR) for capturing features of computer-based systems to enable reengineering for concurrency. A novel feature of the IR is that it incorporates the mission critical software architecture, a view that enables information to be captured at five levels of granularity: the element/program level, the task level, the module/class/package level, the method/procedure level, and the statement/instruction level. An approach to reverse engineering is presented, in which the IR is captured, and is analyzed to identify potential concurrency. Thus, the paper defines concurrency metrics to guide the reengineering tasks of identifying, enhancing, and assessing concurrency, and for performing partitioning and assignment. Concurrency metrics are defined at several tiers of the mission critical software architecture. In addition to contributing an approach to reverse engineering for computer-based systems, the paper also discusses a reverse engineering analysis toolset that constructs and displays the IR and the concurrency metrics for Ada programs. Additionally, the paper contains a discussion of the context of our reengineering efforts within the United States Navy, by describing two reengineering projects focused on sussystems of the AEGIS Weapon System
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