Top PDF Method of forming a skeletal dome structure in situ

Method of forming a skeletal dome structure in situ

Method of forming a skeletal dome structure in situ

A skeletal dome structure composed of a plurality of arcuate support beams joined at their upper ends to a central hub and radiating outwardly and downwardly to terminate at points of engagement with a support surface. Each support beam is composed of an elongated lightweight core sandwiched between upper and lower strips of a material having high tensile and compressive strength. In making the dome, each beam is first preassembled to the extent that the core thereof is secured to a first strip, that strip is then attached at one end to the central hub, the first strip and core are then longitudinally flexed to develop a convex curvature along the side of the core opposite from the strip, and a second flexible strip is then secured to the convex side of the core. A plurality of such beams may be simultaneously formed into buckled or arcuate shape by connecting a plurality of the first strips to a single hub and then raising the hub to impart a curvature into each of the partially-finished beams, followed by the final step of securing the outer strips or skins to the convex upper surfaces of all of the outwardly-radiating arcuate members.
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A SELECTIVE AND SPECIFIC RP HPLC METHOD DEVELOPMENT AND VALIDATION OF CURCUMIN AND STUDY OF ITS APPLICATION IN IN SITU FORMING GEL

A SELECTIVE AND SPECIFIC RP HPLC METHOD DEVELOPMENT AND VALIDATION OF CURCUMIN AND STUDY OF ITS APPLICATION IN IN SITU FORMING GEL

The developed method was applied to the assay of curcumin in situ forming gel. The drug content was calculated as an average of six determinations. A quantity of in situ gel equivalent to10mg of curcumin was taken in a 10 ml volumetric flask and drug was extracted with HPLC grade methanol. The extracts were pooled into a 10 ml volumetric flask and then made up the volume to 10 ml. Further dilutions were prepared with mobiles phase to obtain a concentration of about 10µg of curcmin per ml. The solution was filtered with sample filtration unit (the pore size: 0.22µm), degassed and 20 µl volumes were injected into HPLC in triplicate.
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Mechanistic analysis of Zein nanoparticles/PLGA triblock in situ forming implants for glimepiride

Mechanistic analysis of Zein nanoparticles/PLGA triblock in situ forming implants for glimepiride

In vitro drug release studies from the prepared glimepiride- loaded PLGA–PEG–PLGA in situ gel were evaluated using a modified dialysis. For gel formation, 1 mL sample, equivalent to 15 mg glimepiride, of the homogenized triblock polymeric dispersion of glimepiride-loaded Zein nanopar- ticles was injected into a dialysis tube containing 10 mL of phosphate buffer solution pH 7.2. The dialysis tube (Spectra/ Por 1; Spectrum Laboratories Inc., Rancho Dominguez, CA, USA) employed was a hydrophilic cellulose membrane with symmetric porosity and molecular weight cut-off of 6,000–8,000 Da. The dialysis tubes were hermetically sealed and inserted into the vessels of USP II dissolution apparatus. Phosphate buffer solution (450 mL, pH 7.2) was used as receptor medium at 37 ° C, with a rotational speed maintained at 100 rpm. Aliquots, 3 mL each, were withdrawn from the external medium at time intervals and replaced with the same volume of fresh medium. The samples were assayed for glimepiride content using the previously mentioned in-house developed and validated analytical chromatographic method. All the experiments were performed in triplicate, and the mean cumulative drug release ± SD were calculated.
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Development of in situ Forming Hydrogels for Intra-articular Drug Delivery

Development of in situ Forming Hydrogels for Intra-articular Drug Delivery

A suitable thermo-responsive hydrogel formulation for injection into joints is one for which the polymer forms a low-viscosity solution that can easily be drawn into an 18-gauge needle at 4 C (fridge temperature) and that forms a gel at 37 C (body temperature). Polymers were added to PBS at 5, 10, 15, 20 and 25 wt% and were first evaluated qualitatively for their ability to dissolve at 4 C and then to gel at 37 C. It should be noted that while we refer to the process as dissolution, it is known that the amphiphilic block copolymers are not technically dissolved at the molecular level but actually form micelles. 37 The micelles can be detected by dynamic light scattering but due to their sub-100 nm diameter do not scatter much light. Therefore, the suspensions appear transparent to the naked eye. The vial inversion method was used to differentiate gels from viscous liquids at 37 C. 24, 42 Vials containing the formulations were brought to 37 C for 30 min, then
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FORMULATION AND DEVELOPMENT OF IN SITU FORMING GEL FOR THE TREATMENT OF ORAL THRUSH

FORMULATION AND DEVELOPMENT OF IN SITU FORMING GEL FOR THE TREATMENT OF ORAL THRUSH

Mucoadhesive force can be termed as strength required to disconnect the formulated gel from oral mucosa. Mucoadhesive force was determined using modified balance technique. This method was done using chicken mucosa and two vials. Tissue specimen with appropriate thickness and surface area was taken from chicken mucosa and tied to each side of vial using thread and stored at 32–34°C for about 15 min. Weighing balance was attached to one of the vials and specified quantity of gel was positioned between the tissue specimens attached to bottom of the vials. The force required to detach the gel from mucosa was measured [16].
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 FORMULATION AND EVALUATION OF IN-SITU FORMING LIPOSOMES OF GLICLAZIDE

 FORMULATION AND EVALUATION OF IN-SITU FORMING LIPOSOMES OF GLICLAZIDE

Heat fusion method was the method of choice for formulation of liposomal drug delivery system (LDDS) in this study. In this method the formulation was prepared by mixing the Surfactant mixture in a porcelain dish at 70°C followed by the addition of soybean oil at same temperature. The mixture was homogenously mixed on a magnetic stirrer and GLZ was added at 40°C and stirred constantly until homogenous dispersion was obtained. This final dispersion mixture was then rapidly solidified at room temperature and stored in desiccators for further use.
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Development and optimization of in-situ forming microparticles for long term controlled delivery of deslorelin acetate

Development and optimization of in-situ forming microparticles for long term controlled delivery of deslorelin acetate

ISFM equivalent to 3 mg deslorelin acetate was injected into 10 mL phosphate buffer pH 7.4, containing 0.1% sodium azide and 0.1% Tween 80 maintained at 37°C and shaken in a water bath shaker. Aliquots of release samples (n=3)were withdrawn and replaced by fresh release media at 0.25, 0.5, 1, 2, 4, 6, 8, 10, 12, 14, 18, 22, 26 and 30 days. The deslorelin concentration in the withdrawn samples was determined by HPLC method. Cumulative percent drug release was calculated after correcting the values for withdrawn sample (Singh and Singh, 1998). The in vitro drug release data obtained from ISFM systems were fitted to various release kinetic models viz., zero-order, first- order, Hixson-Crowell, Higuchi and Korsemeyer-Peppas mathematical models (Higuchi, 1963; Korsemeyer et al., 1983; Peppas and Sahlin, 1989).
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<p>In Situ Forming Injectable Hydrogel For Encapsulation Of Nanoiguratimod And Sustained Release Of Therapeutics</p>

<p>In Situ Forming Injectable Hydrogel For Encapsulation Of Nanoiguratimod And Sustained Release Of Therapeutics</p>

IL-1 β , IL-6, and TNF- α are crucial in fl ammatory cyto- kines in the process of in fl ammation in RA and are asso- ciated with the disease activity. The expression levels of in fl ammatory cytokines (IL-1 β , IL-6, and TNF- α ) in the serum and supernatant of the synovial tissue homogenate demonstrate the ef fi cacy of NanoIGUR-loaded hydrogel in the treatment of CIA rats. Subcutaneous injection of 10 mg/kg NanoIGUR-loaded hydrogel every 3 days achieved the same therapeutic effect as the oral administration of 10 mg/kg raw IGUR daily. By changing the dosage form of IGUR into NanoIGUR-loaded hydrogel, we reduced the dosage of raw drugs, achieved long-term and sustained release, and acquired the same therapeutic effect. Although it is not ideal to apply the three-day administra- tion of NanoIGUR-loaded hydrogel in clinical application, our research provides a kind of new thinking and method. Further improvements in the composition of hydrogels may extend the interval of administration.
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IN SITU OPHTHALMIC GEL FORMING SOLUTION OF MOXIFLOXACIN HYDROCHLORIDE FOR SUSTAINED OCULAR DELIVERY

IN SITU OPHTHALMIC GEL FORMING SOLUTION OF MOXIFLOXACIN HYDROCHLORIDE FOR SUSTAINED OCULAR DELIVERY

CONCLUSION: Drug delivery to ocular mucosa for the treatment of ocular disease is associated with many obstacles. After instillation of conventional eye drops major fraction of the instilled dose is lost while less than 5% of the applied drug penetrates the cornea and reaches intraocular tissues. Ocular efficiency of topically applied drugs is influenced by the corneal contact time, most common method of improving ocular availability of drugs is to increase precorneal residence time by using in situ gels. The developed In situ gel forming solution showed better physico chemical attributes than the conventional ophthalmic formulations. Hence, the developed in situ gel forming solution can be used as an alternative to conventional eye drops for the treatment of various ocular infections by increasing the precorneal residence time and thus reducing the dosage interval.
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In-Situ Monitoring Method for Direction Finding Antennas

In-Situ Monitoring Method for Direction Finding Antennas

According to the foregoing, the importance of developing an in-situ measurement system around the DFA array is demonstrated. Because of the difficulty of accessing the far field of the antenna in-situ, the proposed system consists in monitoring the near field of the Antenna under Test (AUT) (see Fig. 5). A number of transmitters (probes array) are placed around the DFA. A near-field calibration is performed. In this new calibration, the wave is generated successively by each of the probes, which operates in the transmit mode. The response of the antenna array is stored for each probe stimulus. A new table called “monitoring table” is then set and stored on the system memory. Once placed in-situ, the monitoring system can transmit with a low duty cycle, which depends on the context stationarity. The current induced in each antenna of the DF array [I ] N F is measured and compared with [I 0 ] N F . The difference
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Organizational Structure Forming Problems in Modern Industrial Enterprise

Organizational Structure Forming Problems in Modern Industrial Enterprise

According to N. Paliulis, E. Chlivickas (1998) the organizational structure first of all depends on its obje c- tives and long-term plans. While organizing the struc- ture one must fulfill all the traditional jobs of the forma- tion of organizational structure: labour sharing (opti- mum division of work as a whole into the separate jobs or operations and the appointment of specific employees or workers who will do these jobs), formation of struc- tural skills (definition of the composition of the em- ployees and enterprise divisions and communication between them), hierarchy creation (the creation of the specific number of the management levels), coordina- tion (correction of the activities of the executives in case their actions do not correspond to the adopted plan). In this case, the operation system of the external and internal factors is significantly expanded. Accord- ing to M. Goold and A. Campbell (2002) the optimum organizational structure depends on 4 organization ac- ceptability factors and 5 organization structural princi- ples for the investigation of which the test prepared by the Centre of London Ashridge Strategic management is suggested. This test is divided into four acceptability tests and five structure tests (Figure 5).
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Combined method for die compensation in sheet metal forming

Combined method for die compensation in sheet metal forming

A numerical simulation with a finite element method has become a powerful tool in preventing the unwanted effects of sheet metal technological processing (Laurent et al., 2010) including springback prediction, compensation and opti- mization(Meinders et al., 2008). One of the most important problems in sheet metal forming is the compensation of a springback (Li et al., 2002). In many cases the shape deviation of the sprung back part and the desired product is so large that the springback compensation is needed to obtain the desired product. That problem then becomes very crucial when the requirement of the shape accuracy is high. Many efforts have been done to eliminate the it by several researchers, the accuracy in springback measurement by Cardena et al. (2002), the modeling, screening, and solving of optimization problems in metal forming processes by Bonte et al. (2004), and Demirci et al. (2008). Therefore, the reduction of spring- backs, while also avoiding excessive strain, is important to the success of a sheet metal-forming process.
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Genetic Structure of Rauscher Spleen Focus-Forming Virus

Genetic Structure of Rauscher Spleen Focus-Forming Virus

1217-1222 0022-538X/83/031217-06$02.00/0 Copyright C 1983, American Society for Microbiology Genetic Structure of Rauscher Spleen Focus-Forming Virus RICHARD BESTWICK,1 MARTIN RUTA,1 ANN[r]

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AGE RELATED CHANGES IN THE STRUCTURE AND FUNCTION OF SKELETAL MUSCLES

AGE RELATED CHANGES IN THE STRUCTURE AND FUNCTION OF SKELETAL MUSCLES

1. For animals of all ages, during activation of skeletal muscles and the subsequent contraction, the balance between the force developed by the muscle and the external load determines whether the muscle shortens, remains at fixed length (isometric) or is lengthened. With maximum activation, the force developed is least during shortening, intermediate when muscle length is fixed and greatest during lengthening contractions. During lengthening contractions, when force is high, muscles may be injured by the contractions.

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An alternate method to springback compensation for sheet metal forming

An alternate method to springback compensation for sheet metal forming

In this research, two different methods, displacement adjust- ment (DA) and spring forward (SF), are joined in alternate manner to compensate the die tools to minimize springback error called hybrid method (HM). When it is used in one algorithm, there are advantages to converge faster and abili- ties to compensate in all sides. A new approach in springback accommodation using the alternate hybrid method (HM) has been tested in two- and three-dimensional springback problem models. The results show that in two-dimensional models, it can reduce the springback up to 66% in after five iteration cycles and in three-dimensional 55%. In the comparison result with Autoform, the HM method shows better performance while the Autoform can reduce 22% and 35% only for two- and three-dimensional models. The HM is an alternate method to reduce springback error based on die tool compensation. This is applicable for sheet metal forming on stamping process having lower and upper dies.
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A New Team Forming Method in Engineering Design Course

A New Team Forming Method in Engineering Design Course

In this study, the author tested a new team forming method in order to effectively run the freshmen based course, Introduction to Engineering Design. Previously, students autonomously formed into teams in the beginning of the semester and completed the project by the end. However, in this new research, during the theory class continued until halfway through the semester, students had a chance to determine other students’ willingness and abilities in weekly regular practices and formed into teams for the first time to complete a Lego Mindstorm project where they practiced writing a proposal. Then, they spontaneously selected their teammates for the 5 week team project, which makes this team forming model flexible. According to the results of a survey, the students’ satisfaction rate on the team forming method was higher than the conventional fixed team forming one. Particularly, in terms of teaming method, the satisfaction rate of the existing method is lower by 7.42% in 2015-2016 than in 2014. However, the satisfaction of the team formation of the students increased by 8.43% in terms of the proposed teaming method. This shows quantitative excellence in the proposed teaming method. Also, regardless of the team’s performance, to avoid the often unreasonable distribution of the same grades among teammates, in the final project stage, students were also evaluated based on self-assessment, which greatly contributed to avoiding grades solely based on team performance.
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Free Energy and Structure of Helix-forming Peptides: A Theoretical Investigation.

Free Energy and Structure of Helix-forming Peptides: A Theoretical Investigation.

Generally speaking, helical conformation of a protein require stabilization of the structure with hydrogen bonding (i + h → i), and to form those bonds h subsequent residues should have corresponding helical dihedral angles (φ, ψ). We already showed energy distribution of hydrogen bonds within α-helix ensemble with fixed dihedral angles, which were constrained to preserve helical configuration (Figure 3.3). We can also take a look at the distribution of hydrogen bonds, while dihedral angles are fixed, and vice versa , the distribution of dihedral angles within the protein backbone, when helical structure preserved by hydrogen bonding. And in general, calculation of free energy difference, using SMD simulations require an equilibrium distribution of initial structures. So we will use those ensembles later in our simulation, which were generated as follows. Initial peptide structures with dihedral angles corresponding to the canonical values of the different helices were generated, and relaxed using energy minimization. These then were subject to a 200 ns MD equilibration runs, with the hydrogen bonds between residue i+ h and i constrained (here h = 3, 4, 5 for 3 10 , α, and π helices respectively) in order to
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The Riddle of the Dome of the Rock:

The Riddle of the Dome of the Rock:

Abd el-Malik was called ‘The Righteous’ by the Jews of the time but an unbeliever (Kaffir) by the Islamic historians. Why? Why did the Moslems replace his name in the writings in the Dome? Ofir offers: The Dome of the Rock is a Jewish building. He explains this with historical evidence but also by the character of the building which he says is of completely Jewish design.

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In situ and time resolved nucleation and growth of silica nanoparticles forming under simulated geothermal conditions

In situ and time resolved nucleation and growth of silica nanoparticles forming under simulated geothermal conditions

Abstract: Detailed knowledge of the reaction kinetics of silica nanoparticles formation in cooling supersaturated waters is fundamental to the understanding of many natural processes including biosilicifcation, sinter formation, and silica diagenesis. Here, we quantified the formation of silica nanoparticles from solution as it would occur in geothermal waters. We used an in situ and real-time approach with silica polymerisation being induced by fast cooling of a 230oC hot and supersaturated silica solution. Experiments were carried out using a novel flow-through geothermal simulator system that was designed to work on-line with either a synchrotron-based small angle X-ray scattering (SAXS) or a conventional dynamic light scattering (DLS) detector system. Our results show that the rate of silica nanoparticle formation is proportional to the silica concentration (640 vs. 960ppm), and the first detected particles form spheres of approximately 3 nm in diameter. These initial nanoparticles grow and reach a final particle diameter of approximately 7 nm. Interestingly, neither variations in ionic strength (0.02 vs. 0.06) nor temperature (reactions at 30 to 60ºC, mimicking Earth surface values) seem to affect the formation kinetics or the final size of the silica nanoparticles formed. Comparing these results with our previous data from experiments where silica polymerisation and nanoparticle formation was induced by a drop in pH from 12 to near neutral [pH-induced, Tobler D.J., Shaw S. and Benning L.G. (2009) Quantification of initial steps of nucleation and growth of silica nanoparticles: an in-situ SAXS and DLS study. Geochim. Cosmochim. Acta 73, 5377-5393] showed that (a) the
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A Method for Determining Skeletal Lengths from DXA Images

A Method for Determining Skeletal Lengths from DXA Images

Fifty normal subjects with whole body DXA scans (scanned in 1999 and 2003), as part of the TwinsUK Reg- istry at St Thomas Hospital [22-24], were used to test the reproducibility of the two measurement techniques. This population were unselected unrelated female Caucasians between the ages of 18 and 80 years old. Both sets of scans were performed on the same QDR 4500W system (Hologic Inc, Bedford, MA). This scanner's fan-beam geometry could affect width measurements (at right angles to the long axis of the scanning table) despite ver- tical measures (parallel to the long axis of the scanning table) remaining accurate. Scans were measured for stand- ing height and regional lengths (spine, femur, tibia and radius) using a 4 cm reticule and 30 cm ruler. The same scans were then measured at the same skeletal sites using the special analysis tool on the DXA machine. This is available in the analysis mode where there is an option for sub-regional analysis. Here, the technician can place up to seven polygonal ROIs on the image to isolate various bone and soft tissue areas. Both measurement techniques were applied to scans from 2003 by one observer and repeated a week later to determine intra-observer error. Long-term precision was tested between 1999 and 2003 scans. This error also accounts for the longitudinal change occurring naturally in bone over time. The time taken to use each method was also recorded.
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