scholarly journals Analysis of Interconnected Arrivals on Queueing-Inventory System with Two Multi-Server Service Channels and One Retrial Facility

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 576
Author(s):  
K. Jeganathan ◽  
T. Harikrishnan ◽  
S. Selvakumar ◽  
N. Anbazhagan ◽  
S. Amutha ◽  
...  
Keyword(s):  
Geometric Approach ◽  
Inventory Systems ◽  
R Matrix ◽  
Ordering Policy ◽  
Optional Service ◽  
Laplace Transform Technique ◽  
The Stability ◽  
Service Channels ◽  
Multi Server

Present-day queuing inventory systems (QIS) do not utilize two multi-server service channels. We proposed two multi-server service channels referred to as T1S (Type 1 n-identical multi-server) and T2S (Type 2 m-identical multi-server). It includes an optional interconnected service connection between T1S and T2S, which has a finite queue of size N. An arriving customer either uses the inventory (basic service or main service) for their demand, whom we call T1, or simply uses the service only, whom we call T2. Customer T1 will utilize the server T1S, while customer T2 will utilize the server T2S, and T1 can also get the second optional service after completing their main service. If there is a free server with a positive inventory, there is a chance that T1 customers may go to an infinite orbit whenever they find that either all the servers are busy or no sufficient stock. The orbital customer can request for T1S service under the classical retrial policy. Q(=S−s) items are replaced into the inventory whenever it falls into the reorder level s such that the inequality always holds n<s. We use the standard (s,Q) ordering policy to replace items into the inventory. By varying S and s, we investigate to find the optimal cost value using stationary probability vector ϕ. We used the Neuts Matrix geometric approach to derive the stability condition and steady-state analysis with R-matrix to find ϕ. Then, we perform the waiting time analysis for both T1 and T2 customers using Laplace transform technique. Further, we computed the necessary system characteristics and presented sufficient numerical results.

scholarly journals The traditional experience strategy (TES) and combined ultrasonography examination (CUE) for the treatment of lateral compression type 1 pelvic fractures: a historical control study

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hai Huang ◽  
Bin-Fei Zhang ◽  
Ping Liu ◽  
Hong-Li Deng ◽  
Peng-Fei Wang ◽  
...  
Keyword(s):  
Pelvic Fractures ◽  
Definitive Treatment ◽  
Lateral Compression ◽  
Level Of Evidence ◽  
Conservative Group ◽  
Medical Records System ◽  
The Stability ◽  
And Function ◽  
Compression Type

Abstract Background It is difficult to judge the stability of lateral compression type-1 (LC-1) pelvic fracture, as it is often based on static images of the pelvis. Compared with the traditional experience strategy, ultrasonography examination may be able to distinguish operative and conservative patients before definitive treatment. However, in previous studies, we have not compared the outcomes between traditional experience strategy (TES group) and combined ultrasonography examination (CUE group). Thus, the aim of the study is comparing the differences between TES and CUE strategy, to identify the value of ultrasonography examination. Methods Medical records system for patients with LC-1 pelvic fractures who were treated with TES and CUE strategy were included. Patients’ baseline characteristics, treatment strategy, and function were recorded at follow-up. Functional outcomes were evaluated using the Majeed grading system. Results In total, 77 patients with LC-1 pelvic fractures were included in the study. There were 42 and 35 patients in TES and CUE group, respectively. Compared to TES group (69 %), there were less proportion patients chosen the operative treatment in CUE group (43 %, P = 0.021). The volume of intraoperative blood loss in CUE operative group was more than TES operative group (P = 0.037). There were more patients with complete sacral fracture in CUE operative group than TES operative group (P = 0.002). The Majeed scores in CUE conservative group was higher than TES conservative group (P = 0.008). The overall Majeed scores in CUE group was higher than that in TES group (P = 0.039). Conclusions The ultrasonography examination could relatively accurately identify the unstable LC-1 pelvis than the traditional experience strategy, the operative rate could be reduced and the overall function of LC-1 patients could be improved under the ultrasonography examination. Level of evidence Level III.

scholarly journals Quiescent Gap Solitons in Coupled Nonuniform Bragg Gratings with Cubic-Quintic Nonlinearity

2021 ◽  
Vol 11 (11) ◽  
pp. 4833
Author(s):  
Afroja Akter ◽  
Md. Jahedul Islam ◽  
Javid Atai
Keyword(s):  
Numerical Stability ◽  
Bragg Gratings ◽  
Stability Boundaries ◽  
Quintic Nonlinearity ◽  
Numerical Stability Analysis ◽  
Gap Solitons ◽  
The Stability ◽  
Dual Core

We study the stability characteristics of zero-velocity gap solitons in dual-core Bragg gratings with cubic-quintic nonlinearity and dispersive reflectivity. The model supports two disjointed families of gap solitons (Type 1 and Type 2). Additionally, asymmetric and symmetric solitons exist in both Type 1 and Type 2 families. A comprehensive numerical stability analysis is performed to analyze the stability of solitons. It is found that dispersive reflectivity improves the stability of both types of solitons. Nontrivial stability boundaries have been identified within the bandgap for each family of solitons. The effects and interplay of dispersive reflectivity and the coupling coefficient on the stability regions are also analyzed.

scholarly journals Role of Vif in Stability of the Human Immunodeficiency Virus Type 1 Core

2000 ◽  
Vol 74 (23) ◽  
pp. 11055-11066 ◽  
Author(s):  
Åsa Öhagen ◽  
Dana Gabuzda
Keyword(s):  
Human Immunodeficiency Virus ◽  
Dna Synthesis ◽  
Virus Entry ◽  
Wild Type ◽  
The Core ◽  
Immunodeficiency Virus ◽  
The Stability ◽  
Hiv 1

ABSTRACT The Vif protein of human immunodeficiency virus type 1 (HIV-1) is important for virion infectivity. Previous studies have shown thatvif-defective virions exhibit structural abnormalities in the virus core and are defective in the ability to complete proviral DNA synthesis in acutely infected cells. We developed novel assays to assess the relative stability of the core in HIV-1 virions. Using these assays, we examined the role of Vif in the stability of the HIV-1 core. The integrity of the core was examined following virion permeabilization or removal of the lipid envelope and treatment with various triggers, including S100 cytosol, deoxynucleoside triphosphates, detergents, NaCl, and buffers of different pH to mimic aspects of the uncoating and disassembly process which occurs after virus entry but preceding or during reverse transcription.vif mutant cores were more sensitive to disruption by all triggers tested than wild-type cores, as determined by endogenous reverse transcriptase (RT) assays, biochemical analyses, and electron microscopy. RT and the p7 nucleocapsid protein were released more readily from vif mutant virions than from wild-type virions, suggesting that the internal nucleocapsid is less stably packaged in the absence of Vif. Purified cores could be isolated from wild-type but not vif mutant virions by sedimentation through detergent-treated gradients. These results demonstrate that Vif increases the stability of virion cores. This may permit efficient viral DNA synthesis by preventing premature degradation or disassembly of viral nucleoprotein complexes during early events after virus entry.

Development of Microemulsions Containing Carthamus tinctorius Extract for 5α-Reductase Inhibition

2019 ◽  
Vol 819 ◽  
pp. 92-97
Author(s):  
Sitthiphong Soradech ◽  
Khaunnapa Panapong ◽  
Surada Soonthornsatitwong ◽  
Somkamol Manchun ◽  
Sirinan Tubtimted ◽  
...  
Keyword(s):  
Transdermal Delivery ◽  
Reductase Activity ◽  
Skin Permeation ◽  
Carthamus Tinctorius ◽  
Permeation Rate ◽  
Du145 Cells ◽  
Thai Medicinal Plants ◽  
The Stability ◽  
Stability Results

The purpose of this study was to develop micromeulsion consisting of Carthamus tinctorius floret extract (CT) as an ingredient to inhibit 5α-reductase activity. CT was extracted using a simple maceration technique with ethanol and inhibition of 5α-reductase activities was determined. Solutions of 2% CT extract were loaded into four microemulsion (ME) formulas (F1, F2, F3 and F4) and investigated for their physical properties, skin permeation and stability. Results showed that crude CT extract had no toxic effects on DU145 cells at concentrations of 0.0001-1.0 mg/mL. For reduction of 5α-reductase activities, concentration of CT extract at 0.05 mg/mL exhibited highest 5-reductase type-1 inhibition activity on the DU-145 cell line at 89.96% of the control, higher than standard finasteride (31.39%) and dutasteride (38.58%). The results indicated that a thermodynamically stable microemulsion improved the stability and permeation rate of CT extract. Among the ME formula, F3 was most appropriate for ME formulation with highest permeation rate and good stability during 30 days of storage. Therefore, using nanotechnology for stable transdermal delivery systems of bioactive compounds from Thai medicinal plants is one approach to improve skin and hair follicle permeation.

Analysis of an infinite multi-server queue with an optional service

2013 ◽  
Vol 65 (2) ◽  
pp. 216-225 ◽  
Author(s):  
Jau-Chuan Ke ◽  
Chia-Huang Wu ◽  
Wen Lea Pearn
Keyword(s):  
Optional Service ◽  
Server Queue ◽  
Multi Server

scholarly journals Sensitivity to a Nonpeptidic Compound (RPR103611) Blocking Human Immunodeficiency Virus Type 1 Env-Mediated Fusion Depends on Sequence and Accessibility of the gp41 Loop Region

2000 ◽  
Vol 74 (5) ◽  
pp. 2142-2150 ◽  
Author(s):  
Béatrice Labrosse ◽  
Carole Treboute ◽  
Marc Alizon
Keyword(s):  
Human Immunodeficiency Virus ◽  
Drug Resistance ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Conformational Changes ◽  
Loop Region ◽  
Immunodeficiency Virus ◽  
The Stability ◽  
Hiv 1

ABSTRACT The triterpene RPR103611 is an efficient inhibitor of membrane fusion mediated by the envelope proteins (Env, gp120-gp41) of CXCR4-dependent (X4) human immunodeficiency virus type 1 (HIV-1) strains, such as HIV-1LAI (LAI). Other X4 strains, such as HIV-1NDK (NDK), and CCR5-dependent (R5) HIV-1 strains, such as HIV-1ADA (ADA), were totally resistant to RPR103611. Analysis of chimeric LAI-NDK Env proteins identified a fragment of the NDK gp41 ectodomain determining drug resistance. A single difference at position 91, leucine in LAI and histidine in NDK, apparently accounted for their sensitivity or resistance to RPR103611. We had previously identified a mutation of isoleucine 84 to serine in a drug escape LAI variant. Both I84 and L91 are located in the “loop region” of gp41 separating the proximal and distal helix domains. Nonpolar residues in this region therefore appear to be important for the antiviral activity of RPR103611 and are possibly part of its target. However, another mechanism had to be envisaged to explain the drug resistance of ADA, since its gp41 loop region was almost identical to that of LAI. Fusion mediated by chimeric Env consisting of LAI gp120 and ADA gp41, or the reciprocal construct, was fully blocked by RPR103611. The gp120-gp41 complex of R5 strains is stable, relative to that of X4 strains, and this stability could play a role in their drug resistance. Indeed, when the postbinding steps of ADA infection were performed under mildly acidic conditions (pH 6.5 or 6.0), a treatment expected to favor dissociation of gp120, we achieved almost complete neutralization by RPR103611. The drug resistance of NDK was partially overcome by preincubating virus with soluble CD4, a gp120 ligand inducing conformational changes in the Env complex. The antiviral efficacy of RPR103611 therefore depends on the sequence of the gp41 loop and the stability of the gp120-gp41 complex, which could limit the accessibility of this target.

scholarly journals Analysis of a Dengue Disease Model with Nonlinear Incidence

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Shu-Min Guo ◽  
Xue-Zhi Li ◽  
Mini Ghosh
Keyword(s):  
Numerical Simulations ◽  
Epidemic Model ◽  
Disease Model ◽  
Geometric Approach ◽  
Backward Bifurcation ◽  
Nonlinear Incidence ◽  
Dengue Disease ◽  
Proposed Model ◽  
The Stability

A dengue disease epidemic model with nonlinear incidence is formulated and analyzed. The equilibria and threshold of the model are found. The stability of the system is analyzed through a geometric approach to stability. The proposed model also exhibits backward bifurcation under suitable conditions on parameters. Our results imply that a nonlinear incidence produces rich dynamics and they should be studied carefully in order to analyze the spread of disease more accurately. Finally, numerical simulations are presented to illustrate the analytical findings.

The stability of the intratypic antigenic character of sabin's type 1 attenuated virus (LSc-2ab)

1963 ◽  
Vol 12 (1) ◽  
pp. 7-16 ◽  
Author(s):  
V. Yonka ◽  
Z. Janda ◽  
J. Šimon
Keyword(s):  
Attenuated Virus ◽  
The Stability
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