scholarly journals Comparison of Some Physical Parameters of Whole and Scored Lisinopril and Lisinopril/Hydrochlorthiazide Tablets

2008 ◽  
Vol 8 (4) ◽  
pp. 391-395 ◽  
Author(s):  
Edina Vranić ◽  
Alija Uzunović

Tablets are one of the most popular and preferred solid dosage forms because they can be accurately dosed, easily manufactured and packaged on a large scale, have good physical and chemical stability, and can contribute to good patient compliance given their ease of administration. The ability to match doses to patients depends on the availability of multiple dose sizes and adequate dose-response information. These are not always provided, so splitting of the tablets is sometimes necessary, Tablet splitting is an accepted practice in dispensing medication, It has been used when a dosage form of the required strength is not available commercially. The aim of our study was to compare some physical parameters of whole and scored lisinopril and lisinopril/hydrochlorthiazide tablets and to accept or exclude their influence on the obtaining of required dosage.According to the results obtained, we may conclude that tablets from batch “I” “IL “III” and “IV” satisfied pharmacopeial requirements concerning crushing strength, friability, disintegration time and mass uniformity. The hardness testing showed acceptable reproducibility and indicate that the data variation was primarily from the irreversible changes in the structure of tablet samples. The act of compacting powders stores energy within the tablets, by shifting or compressing the intermolecular bonds within the particles. The tablets have a natural tendency to relax once pressure is removed, and this tendency works against the interparticle bonding formed during compression. Hardness testing procedure causes irreversible changes in this structure.

Author(s):  
Dumpeti Janardhan ◽  
Joginapally Sreekanth ◽  
P.Theja Pavan Kumar ◽  
M.Vamshi Krishna

The purpose of this study was to evaluate the potential of polymers for masking the taste of bitter drugs when incorporated into orally disintegrating tablets. The tablets were produced by simple wet granulation technique with a model compound (baclofen) which is moderately bitter. The formulating procedure had two variables to obtain good taste masking with desirable characteristics. The optimal granulation process parameters were polymer selection and its concentration (w/w), suitable for pilot scale level. Dextrates, β- cyclodextrin, eudragit EPO and PVP K-30 were used in preparation of granules by using water and iso-propyl alcohol. Crospovidone was used intra and extra granularly as superdisintegrant.  Sodium bicarbonate and citric acid were used as effervescent for fast disintegration of tablets, which also optionally act as desensitizer of taste buds. Results from evaluation of tablets indicated a disintegration time (avg) of 30-35 sec and 100% drug release was achieved within 5 min. But taste masking was achieved by only with eudragit EPO. Results from an evaluation by a panel of six human volunteers demonstrated that the orally disintegrating tablets which are prepared by using polymer Eudragit EPO (5% and 7.5% w/w of tablet) and PVP (7.5% w/w of tablet) improved taste, significantly. On studying physical parameters, F9 formulation demonstrated acceptable level of hardness and friability with good taste masking and it was thus considered as an optimized formulation


2017 ◽  
Vol 11 (6) ◽  
pp. 637-639 ◽  
Author(s):  
Lori Upton ◽  
Thomas D. Kirsch ◽  
Melissa Harvey ◽  
Dan Hanfling

AbstractHealth care coalitions play an increasingly important role in both preparedness for, response to, and recovery from large scale disaster events occurring across the United States. The actions taken by the South East Texas Regional Advisory Council (SETRAC) in response to the landfall of Hurricane Harvey, and the consequential flooding that ensued, serve as an excellent example of how health care coalitions are increasingly needed to play a unifying role in response. This paper highlights a number of the strategic planning, operational planning and response, information sharing, and resource coordination and management activities that were undertaken for the response to Hurricane Harvey. The successful response to this devastating storm in the Houston, Texas area serves as an example to other regions across the country as they work to implement the 2017-2022 health care capabilities articulated by the Department of Health and Human Services Office of the Assistant Secretary for Preparedness and Response. (Disaster Med Public Health Preparedness. 2017;11:637–639)


2021 ◽  
Vol 11 (4) ◽  
pp. 786-791
Author(s):  
Ye Liu ◽  
Guihua Xia ◽  
Shaosheng Liu ◽  
Zhenyu Song

The aim of the present study was to formulate oral chewable tablets of Montelukast (MTL) in the form of nanoparticles (NP’s). The MTL loaded NP’s were formulated by ionotropic external gelation method using tripolyphosphate (TPP) as crosslinking agent and Tween 60 as surfactant. NP’s were characterized for drug loading, encapsulation efficiency, surface morphology, saturation solubility, particle size, zeta potential and polydispersity index. The optimized NP formulation was used for development of chewable tablets using direct compression method. The prepared tablets were characterized for disintegration test, dissolution, thickness, hardness, friability and assay. The optimized formulation was evaluated in asthamatic animals to demonstrate the efficiency in asthama. The encapsulation efficiency of NP’s was found between 91.24 to 98.21% while drug loading was in the range of 10.09–14.25%. All formulations were found of nanosized in nature (110 to 200 nm) with excellent zeta potential (20.12 to 22.27 mV). PDI of all NP formulations were found within acceptable limit (less than 0.3). The nanoparticles were found spherical in shape with smooth surface. The saturation solubility of MTL was enhanced nearly 10 times (92 mg/ml) as compared to pure MTL saturation solubility. All physical parameters of the tablets were found within range. The optimized tablets showed disintegration time of 20 sec while other formulations showed DT in the rage of 35–57 sec. Tab1 (Optimized formulation) showed almost 100% MTL release from chewable tablets within the period of 30 min. Reduction in lung resistance (RI) was found in animals treated with Tab1. This reduction in RI was found nearly two fold and three fold as compare to MTL treated and control group animals. These observations clearly support the efficacy of chewable tablets containing nanoparticulate MTL in asthmatic animals.


1998 ◽  
Vol 120 (1) ◽  
pp. 63-73 ◽  
Author(s):  
K. N. Morman ◽  
E. Nikolaidis ◽  
J. Rakowska ◽  
S. Seth

A constitutive equation of the differential type is introduced to model the nonlinear viscoelastic response behavior of elastomeric bearings in large-scale system simulations for vibration assessment and component loads prediction. The model accounts for the nonlinear dependence of dynamic stiffness and damping on vibration amplitude commonly observed in the behavior of bearings made of particle-reinforced elastomers. A testing procedure for the identification of the model parameters from bearing component test data is described. The experimental and analytical results for predicting the behavior of four (4) different car bushings are presented. In an example application, the model is incorporated in an ADAMS simulation to study the dynamic behavior of a car rear suspension.


2017 ◽  
Vol 826 ◽  
pp. 851-887 ◽  
Author(s):  
Francesco Stella ◽  
Nicolas Mazellier ◽  
Azeddine Kourta

We report an experimental investigation of the separating/reattaching flow over a descending ramp with a $25^{\circ }$ expansion angle. Emphasis is given to mass entrainment through the boundaries of the separated shear layer emanating from the upper edge of the ramp. For this purpose, the turbulent/non-turbulent interface and the separation line inferred from image-based analysis are used respectively to mark the upper and lower bounds of the separated shear layer. The main objective of this study is to identify the physical parameters that scale the development of the separated shear layer, by giving a specific emphasis to the investigation of mass entrainment. Our results emphasise the multiscale nature of mass entrainment through the separated shear layer. The recirculation length $L_{R}$, step height $h$ and free-stream velocity $U_{\infty }$ are the dominant scales that organise the separated flow (and related large-scale quantities as pressure distribution or shear layer growth rate) and set mean mass fluxes. However, local viscous mechanisms seem to be responsible for most of local mass entrainment. Furthermore, it is shown that large-scale mass entrainment is driven by incoming boundary layer properties, since $L_{R}$ scales with $Re_{\unicode[STIX]{x1D703}}$, and in particular by its turbulent state. Surprisingly, the relationships evidenced in this study suggest that these dependencies are established over a large distance upstream of separation and that they might also extend to small scales, at which viscous entrainment is dominant. If confirmed by additional studies, our findings would open new perspectives for designing effective separation control systems.


2021 ◽  
Vol 17 (1) ◽  
pp. 29-45
Author(s):  
Baiba Vērpe

Abstract The paper presents a summary of large-scale buildings of resort establishments of Soviet period in Jūrmala, by analysing their typology, physical parameters, scenarios of the development, architectural stylistic and the present state of physical condition and authentic substance. The research reveals that half of the large-scale resort buildings are already irreversibly lost and the rest of buildings are seriously endangered due to the tendency of extensive rebuilding.


2021 ◽  
Author(s):  
Jana Šafránková ◽  
Zdeněk Němeček ◽  
František Němec ◽  
Luca Franci ◽  
Alexander Pitňa

<p>The solar wind is a unique laboratory to study the turbulent processes occurring in a collisionless plasma with high Reynolds numbers. A turbulent cascade—the process that transfers the free energy contained within the large scale fluctuations into the smaller ones—is believed to be one of the most important mechanisms responsible for heating of the solar corona and solar wind. The paper analyzes power spectra of solar wind velocity, density and magnetic field fluctuations that are computed in the frequency range around the break between inertial and kinetic scales. The study uses measurements of the Bright Monitor of the Solar Wind (BMSW) on board the Spektr-R spacecraft with a time resolution of 32 ms complemented with 10 Hz magnetic field observations from the Wind spacecraft propagated to the Spektr-R location. The statistics based on more than 42,000 individual spectra show that: (1) the spectra of both quantities can be fitted by two (three in the case of the density) power-law segments; (2) the median slopes of parallel and perpendicular fluctuation velocity and magnetic field components are different; (3) the break between MHD and kinetic scales as well as the slopes are mainly controlled by the ion beta parameter. These experimental results are compared with high-resolution 2D hybrid particle-in-cell simulations, where the electrons are considered to be a massless, charge-neutralizing fluid with a constant temperature, whereas the ions are described as macroparticles representing portions of their distribution function. In spite of several limitations (lack of the electron kinetics, lower dimensionality), the model results agree well with the experimental findings. Finally, we discuss differences between observations and simulations in relation to the role of important physical parameters in determining the properties of the turbulent cascade.</p>


2016 ◽  
pp. 1264-1278
Author(s):  
Michael A. Erskine ◽  
Will Pepper

This paper presents a novel approach toward facilitating the effective collection and communication of information during an emergency. Initially, this research examines current emergency response information workflows and emergency responder dispatch criteria. A process for the optimization of these workflows and criteria, along with a suggested method to improve data collection accuracy and emergency response time using a mobile device application, are suggested. Specifically, a design-science approach incorporating the development of an expert system designed to facilitate efficient and effective sharing of emergency information is applied. The resulting benefits could improve emergency communications during large-scale international gatherings, such as sporting events or festivals, as well as the sharing of industry-specific safety incidents. A process model for conducting analyses of additional emergency response processes is also presented. Finally, future research directions are discussed.


Geosciences ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 68 ◽  
Author(s):  
Dorrik Stow ◽  
Zeinab Smillie

The distinction between turbidites, contourites and hemipelagites in modern and ancient deep-water systems has long been a matter of controversy. This is partly because the processes themselves show a degree of overlap as part of a continuum, so that the deposit characteristics also overlap. In addition, the three facies types commonly occur within interbedded sequences of continental margin deposits. The nature of these end-member processes and their physical parameters are becoming much better known and are summarised here briefly. Good progress has also been made over the past decade in recognising differences between end-member facies in terms of their sedimentary structures, facies sequences, ichnofacies, sediment textures, composition and microfabric. These characteristics are summarised here in terms of standard facies models and the variations from these models that are typically encountered in natural systems. Nevertheless, it must be acknowledged that clear distinction is not always possible on the basis of sedimentary characteristics alone, and that uncertainties should be highlighted in any interpretation. A three-scale approach to distinction for all deep-water facies types should be attempted wherever possible, including large-scale (oceanographic and tectonic setting), regional-scale (architecture and association) and small-scale (sediment facies) observations.


Sensors ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 5545 ◽  
Author(s):  
Jidong Zhang ◽  
Jinsong Ping ◽  
Zhaofa Zeng ◽  
Yongzhang Yang ◽  
Xiangyue Li ◽  
...  

Lunar surface temperature is one of the fundamental thermophysical parameters of the lunar regolith, which is of great significance to the interpretation of remote-sensing thermal data. In this study, a daytime surface temperature model is established focusing on the lunar superficial layer with high spatial-temporal resolution. The physical parameters at the time of interest are adopted, including effective solar irradiance, lunar libration, large-scale topographic shading, and surrounding diffuse reflection. Thereafter, the 1/64° temperature distributions at five local times are quantitatively generated and analyzed in Sinus Iridum. Also, combined with Chang’E-2 microwave radiometer (CELMS) data and Diviner thermal infrared (TIR) data, the spectral emissivity distributions are estimated as a potential geological application of the simulated surface temperature. The results are as follows: (1) daytime surface temperature in Sinus Iridum is significantly affected by the local topography and observation time, and the influence of diffuse reflection energy is obvious; (2) the emissivity distributions provide a new way to understand the thermophysical properties difference of lunar regolith at different depths; (3) the influence of lunar orbiting revolution and precession on surface temperature should be analyzed carefully, which shows the importance of using the parameters at the time of interest.


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