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Evans Blue Extravasation to Brain by Surfactant Modified Liposomes

Evans Blue Extravasation to Brain by Surfactant Modified Liposomes

formulation was prepared by using Phospahatidyl choline and cholesterol with different surfactants such as span 20 (ES20), span 40 (ES40), span 80 (ES80) and span 80 and tween 80 combination (EST 80) and without surfactant (ENS) entrapping Evans blue dye (2% dye). In brief, Phosphotidyl choline, cholesterol at a molar ratio of 9:1were dissolved in diethyl ether. To this, Evans blue dye (2% w/v) in 5ml of a Phosphate Buffer Saline (PBS) of pH 7.4 were added along with surfactant span 20. The molar ratios for the surfactants were selected after optimizing based on their stability and vesicle formation. Then they were homogenized using a homogenizer (Tenbroeck tissue grinder - Kontes Glass Co., Vineland, NJ) for 20 minutes at 5000 RPM at 40°C and then sonicated using a probe sonicator (Soniweild, India) for 5 minutes at 40 % frequency. This led to the formation of a reverse (w/o type) emulsion which later forms a semi solid gel like consistency. The residual diethyl ether solvent is evaporated further by using vacuum evaporator (BUCHI EL 131 Rotavapor, Ger many) under reduced pressure (260 - 400 mm Hg) at 60°C. The lipid gel so formed was collapsed and transformed in to a fluid consistency by continuous vigorous mechanical agitation using a vortex mixer (REAX top, Heidolph Instruments GmbH & Co., Schwabach, Germany). To this 5 ml of warm PBS (pH 7.4) was added to hydrate the vesicles thus producing suspension of liposomes. This formulation is designated as ES20. Similarly, other surfactants span 40, span 80 at molar concentration of 1:1(Lipid: surfactant) and span 80 with tween 80 combination at a molar concentration of 1:2:1(Lipid: span 80: tween 80) were prepared and designated as ES40, ES80 and EST80respectively. Without surfactant (ENS) liposomes were prepared by the same procedure but non inclusive of any surfactants. Particle size analysis 11

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Optimization of emulsifying effectiveness of phytosterol in milk using span as emulsifiers by orthogonal experimental design

Optimization of emulsifying effectiveness of phytosterol in milk using span as emulsifiers by orthogonal experimental design

As be shown in Tab.3, the primary and secondary order of factors analyzed by variance analysis of was consistent with the intuitive analysis, Factor A (Span 20) and C (Span 60) were very significant, Factor B (Span 40) was significant and Factor D (Span 40) was not significant, So the optimal condition of emulsification for phytosterol in milk was A 3 B 2 C 2 D 1 , i.e. the concentration of Span 20, Span 40, Span 60 and Span 80 were 0.35%, 0.50%, 0.60% and 0.45%.

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DEVELOPMENT AND ESTIMATION OF ANTI-INFLAMMATORY ACTIVITY OF TOPICAL ETORICOXIB EMULGEL BY CARRAGEENAN INDUCED PAW OEDEMA METHOD

DEVELOPMENT AND ESTIMATION OF ANTI-INFLAMMATORY ACTIVITY OF TOPICAL ETORICOXIB EMULGEL BY CARRAGEENAN INDUCED PAW OEDEMA METHOD

At present scenario, emulgel is one of the recent technologies used for dual control release of emulsion and gel for topical use. Moreover, they will become a solution for loading hydrophobic drugs in water soluble gel bases for the long term stability. The stability of emulsion is increased, when it is incorporated into gel. Etoricoxib is a hydrophobic drug. In current study Etoricoxib was successfully formulated in an emulgel drug delivery with gelling agent like Carbopol 934 and HPMCK4M with emulsifiers like Span 20 and Tween 20 developed with simple, commercial feasible manufacturing process. Etoricoxib emulgel formulation EG1 used in this study showed significant reduction of paw edema thickness and volume at 8 hrs or more after carrageenan injection, demonstrated that the emulgel possess fairly good anti-inflammatory activity.

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FORMULATION AND EVALUATION OF PRONIOSOME BASED DRUG DELIVERY SYSTEM OF VALCYCLOVIR FOR IN-VITRO AND EX-VIVO PERFORMANCE ANALYSIS

FORMULATION AND EVALUATION OF PRONIOSOME BASED DRUG DELIVERY SYSTEM OF VALCYCLOVIR FOR IN-VITRO AND EX-VIVO PERFORMANCE ANALYSIS

A proniosome based drug delivery system of Valcyclovir as planned for development and characterisation for in-vitro performance. Proniosomes containing valcyclovir were prepared by co-acervation method using (span 20, span40, span60, span 80), cholesterol and lecithin at different concentrations. All the proniosomes formulation evaluated for entrapment efficiency, drug content, shape and size distribution, in-vitro and ex-vivo studies. The method of proniosomal encapsulation resulted as 96%-82%. Morphology of F1 Proniosomal formulation was characterised by using scanning electron microscopy (SEM), in-vitro studies showed the prolonged release of entrapped Valcyclovir and ex- vivo studies revealed the Proniosomes prepared with span 80 showed a significantly lower enhancement effect then those prepared with span 20.

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 FORMULATION AND EVALUATION OF BLACK SESAME SEED OIL SUNSCREEN EMULGEL USING NATURAL GELLING AGENT

 FORMULATION AND EVALUATION OF BLACK SESAME SEED OIL SUNSCREEN EMULGEL USING NATURAL GELLING AGENT

prepared by fenugreek seed mucilage and the dispersion was cooled and leftover night. The pH of all the formulations was maintained to 6 - 6.5 by using triethanolamine (TEA). The oil phase of the emulsion was formulated by dissolving Span 20 in light liquid paraffin and Sesamum indicum seed oil was mixed in oil phase. While the aqueous phase was produced by dissolving Tween 20 in purified water. Methyl paraben was dispersed in propylene glycol and mixed with aqueous phase, being lipophilic it was dissolved in oil phase. Both the oily and aqueous phases were individually heated to 70° to 80°C, then the oily phase was added to the aqueous phase with constant swirling until it was cooled to room temperature. The resultant emulsion was mixed with the gel in 1:1 ratio with subtle stirring to obtain the emulgel 14 .

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Phase Diagrams of W/O Microemulsion Stabilised By Non-ionic Surfactants ToBe Used As Templates ForMicroemulsion Polymerisation

Phase Diagrams of W/O Microemulsion Stabilised By Non-ionic Surfactants ToBe Used As Templates ForMicroemulsion Polymerisation

Dynamic light scattering measurements In order to elucidate the different types of colloidal structures present in the prepared microemulsion, DLS measurements were carried outto determine the particle size and distribution. For the light scattering measurements of these mixed non-ionic surfactant microemulsion systems, two lines at a constant weight ratio of surfactant/oil of 50/50 and 90/10 were taken. The line at the 50/ 50 weight ratio shows limited solubility in water of less than 20 percent, while the other line at the 90/ 10 shows complete miscibility in water (see Figure 3). The droplet size of each of the composition is obtained from the particle size distribution described as intensity percent from the DLS measurements. To illustrate this, Figure 5 showed the droplet size distribution described as intensity percent for sample at 50:50 (mixed surfactant/1-Butanol:Methyl Acetate) for H 2 O/Tween 80:Span 20/1-Butanol/ Methyl Acetate containing at 5 weight percent of water. Similar exercises were used for the other compositions and their droplet size with the variation of water content is shown in Figure 6.

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Formulation and Evaluation of Niosomes

Formulation and Evaluation of Niosomes

larger and operate over a much larger distance. DVLO theory suggests that the stability of a colloidal system is determined by the sum of these van der Waals attractive (VA) and electrical double layer repulsive (VR) forces that exist between particles as they approach each other due to the Brownian motion they are undergoing. This theory proposes that an energy barrier resulting from the repulsive force prevents two particles approaching one another and adhering together. Fig. 2 shows the size distribution of the Span 20 niosomal vesicles, which range from 100–1000 nm. The adjuvanticity of a niosome depends on structural characteristics such as vesicle

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Characterizing the Volatility Transmission across International Stock Markets

Characterizing the Volatility Transmission across International Stock Markets

The parameters of the above bi-variate EGARCH model are estimated by numerically maximizing the like- lihood function discussed above using the algorithm developed by Berndt et al. [20] (BHHH 12 ) without impos- ing any parameter restriction. As a note, we would like to mention here that each stock market has different reg- ulations, trading system and transaction costs, which as an assumption, has not been considered in this study. Using the above bivariate EGARCH model, we obtain the spillover parameters which are used for further ana- lyze in the study. There are 45 pairs from 10 stock market data series and approximately 77 estimation windows, each of length one year and rolling over at an interval of a quarter. The rationale for using rolling analysis for our study is for two reasons i.e. to assess a model’s stability over time and to evaluate predictive accuracy.

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Elastocaloric Cooling: State-of-the-art and Future Challenges in Designing Regenerative Elastocaloric Devices

Elastocaloric Cooling: State-of-the-art and Future Challenges in Designing Regenerative Elastocaloric Devices

order to increase the convective heat transfer (similar to a heat-pipe concept). Unfortunately, no cooling characteristics other than the temperature span of the device are published to date. In 2019, another three- stage cascade elastocaloric device with a single Ni-Ti wire loaded in tension was designed, built and tested [44]. A maximum temperature span of 28.3 K was measured, which is currently the largest temperature span measured for elastocaloric devices. Table 1 shows the overview and comparison of the developed proof-of-the-concept elastocaloric devices to date. Maximum temperature span, maximum specific cooling/heating power per mass of the elastocaloric material and the maximum COP and exergy efficiency are presented in Table 1 (if available). The COP is defined as the ratio between the cooling/heating power and the input work, while exergy efficiency is defined as the ratio between the actual COP and the maximum theoretical COP (also called the Carnot COP) that would be possible over a certain temperature span. It should be noted that all the COP values published for elastocaloric devices are based on the assumptions that a perfect recovery of the released mechanical energy is achieved during the unloading and that the input work is only related to the area enclosed in the stress-strain diagram (hysteresis) – see Section 3.2. for more details on mechanical work recovery.

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Adaptive Attention Span in Transformers

Adaptive Attention Span in Transformers

Impact on the attention span. In Figure 4, we show the final attention spans of every attention heads of our small adaptive-span model with S = 4096. Even though all the span sizes are initial- ized to the same value, we see large varieties in their final values. We can see that the lowest 5 layers have the smallest possible attention span, which is R = 32 of the masking function. This indicates that lower layers in a Transformer model do not really require a long attention span in this particular task. In contrast, few attention heads in the higher layers have very long spans, exceed- ing several thousand. Although there is a general tendency of higher layers having longer attention spans, it is not a simple monotonic function of the layer height.

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Neuropsychological Profile and Performance Variability in Vascular Cognitive Impairment

Neuropsychological Profile and Performance Variability in Vascular Cognitive Impairment

Attention span and working memory capacity were assessed by Digit Span and Spatial Span from Wechsler Memory Scale-III (WMS-III; [32]). Processing speed was assessed by Wechsler Adult Intelligence Scale-III (WAIS-III; [33]) Digit Symbol and the color-word trial of the Stroop Test [34]. Memory was assessed by the in- cidental recall trial for Digit Symbol, WMS-III Logical Memory, Rey Auditory Verbal Learning Test [35], Con- tinuous Visual Memory Test [36], and the 30-minute delayed recall score for the Rey-Complex Figure [37] di- vided by the copy score to derive a measure of percent retention. Language was assessed by selected items from the Boston Diagnostic Aphasia Exam (BDAE; [38]). Auditory comprehension was assessed by the number cor- rect for the four paragraphs from the Complex Ideational Materials subtest (items 5 - 12). As a measure of con- frontation naming, two objects (hammock, cactus), two geometric forms (star, triangle) and two body parts (el- bow, wrist) from Visual Confrontation Naming subtest were presented, and each response scored 0 - 3 based on approximate response times, as indicated on the test form. Reading comprehension was assessed using all 10 items from the Reading Sentences and Paragraphs subtest. Visuoconstruction was assessed by Block Design from the Wechsler Abbreviated Scale of Intelligence (WASI; [39]) and the Rey Complex Figure. Executive functions were assessed using a modified short form of the Wisconsin Card Sorting Test [40], the errors made on the color-word trial of the Stroop Test, and a rating from 0 to 3 for each participant’s copy of the Rey Com- plex Figure made by the first author at the time of administration. This rating was made prior to the administra- tion of all other tests except for one measure of word recognition. Normal planning and organization was scored 0, subtle to mild impairment was scored 1, moderate impairment was scored 2, and severe impairment resulting in gross distortion of the figure was scored 3. We have previously shown that lower ratings are associated with impairment in daily living skills [41]. Fluency was assessed using Animal Naming from the BDAE, FAS [42] and a measure of ideational fluency, the Alternate Uses Test [43]. The latter test was developed to assess diver- gent thinking. A modified version used in the present study has been shown to discriminate dementia patients from healthy elderly controls more reliably than measures of verbal fluency [44].

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FABRICATION AND CHARACTERIZATION OF PRONIOSOMAL GEL OF NAPROXEN SODIUM FOR TREATMENT OF INFLAMMATION AND DEGERATIVE DISORDERS OF MUSCULOSKELETAL SYSTEM

FABRICATION AND CHARACTERIZATION OF PRONIOSOMAL GEL OF NAPROXEN SODIUM FOR TREATMENT OF INFLAMMATION AND DEGERATIVE DISORDERS OF MUSCULOSKELETAL SYSTEM

www.wjpr.net Vol 8, Issue 5, 2019. 748 Naproxen proniosomal gel containing lecithin, cholesterol and in combination of surfactants like span 20, 40 and 60 produce sustained release of drug over a period of 12 hrs for the treatment of inflammatory and degenerative disorders of the musculoskeletal system. The proniosomal gel F3 could be an effective alternative vehicle for delivering the drug through transdermal route to avoid side effects associate with oral route.

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New Approaches to Human Development Index

New Approaches to Human Development Index

Replacement of the arithmetic mean with the geometric mean in the 2010’s HDI calculation have prevented the interchangeability of the three components. However, this new method has also been criticized. Thus, most people have not realized that the new calculation implicitly diminishes the weight on the life span in poor countries compared to the rich countries. For example, a poor country with a low life expectancy due to a worsening health system may improve its current HDI with a small economic growth rate. On the other hand, the new HDI's gains from additional education may seem unreasonably high. Ravallion (2012) argued that some such disturbing trade-offs could be avoided by using a different aggregation function for the HDI.

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The Lasting Effects of Language Acquisition: Testing Cognitive Abilities after L2 Attrition

The Lasting Effects of Language Acquisition: Testing Cognitive Abilities after L2 Attrition

The entire study was run through Qualtrics, a link to which was included in the TurkPrime HIT. Participants digitally signed informed consent forms before proceeding with the experiment, which consisted of four cognitive tasks in the following order: forward digit span, nonword repetition, numerical Stroop, and backwards digit span. Two of the four tasks, namely forward and backwards digit span, employed stimuli found in the Digit Span subtests from the Second Edition of the Comprehensive Test of Phonological Processing (CTOPP-2; Wagner, Torgesen, Rashotte, & Pearson, 2013). For each task, participants were given English instructions explaining the task; they then completed three practice trials for that task. Practice and experimental trials were clearly designated as such. The tasks were completed in the following order: forward digit span, reading span task, numerical Stroop, backwards digit span, Spanish proficiency measure, RLCP. All cognitive tasks were performed in English, regardless of group, due to a desire to standardize the tasks across all three groups and concerns about the higher cognitive load that Spanish tasks may impose on L2 attriters and unbalanced bilinguals who were dominant in English.

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An Actuarial Analysis of Calibration of Crop Insurance Premiums to Heterogeneous Risks

An Actuarial Analysis of Calibration of Crop Insurance Premiums to Heterogeneous Risks

The corrections applied for yield span ratio are adequate for only three states. This means that the risk across each yield span is not correctly captured by the premium rate structure of the APHP. The parameter estimates are positive and significant for seven states. This finding of higher loss ratios for units having higher yield span ratiosindicate that the premium rate discounts offered for units with higher yield span ratios are too large. Refering to Figure 1, my results indicate that the current yield span exponential for wheat of –1.5 results in rates that decline too steeply with yield span rates. This is an important result which supports results obtaind by Knight and Coble which indicated a need for corrections to the central element of the APHP rate structure.

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The effects of vitamins C and B12 on human nasal ciliary beat frequency

The effects of vitamins C and B12 on human nasal ciliary beat frequency

The mechanisms of changes in CBF in response to vita- mins treatment are still unclear. Airway CBF is mainly regu- lated by a variety of intracellular second messenger signaling mechanisms including cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), and calcium [20]. cAMP activates an axonemal protein kinase A (PKA) to phosphorylation a dynein light chain to increase CBF; cGMP mediates a phosphorylation or dephosphoryla- tion event to increase CBF via protein kinase G (PKG) and possibly PKA; calcium seems to increase CBF via an initial direct action on the axoneme and subsequently via cross talk to the cAMP or cGMP pathways. A significant amount of work is required to understand fully the mechanisms of regulation of CBF by these vitamins.

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Formulation and In Vitro and Skin Permeability Evaluation of Dexamethasone Loaded Niosomal Gel

Formulation and In Vitro and Skin Permeability Evaluation of Dexamethasone Loaded Niosomal Gel

The aim of this work was to prepare a reservoir type transdermal delivery system with the drug core being formed of a Niosomal Gel and to evaluate the permeation. The present study was focused on the screening of dexamethasone loaded Niosomal Suspension and formulation of a Niosomal Gel. Niosomal Suspension of Dexamethasone prepared by Hand Shaking Method using Span 60, Tween 20 and Tween 80 with addition of Charge Inducer. Prepared Niosomal Suspension selected batch show following results Drug Content (98.10±0.885 %), % Entrapment Efficiency (85.27±0.476), Zeta Potential (-23.0 mV) and Invitro Drug Release (74.168± 0.551). Niosomal Gel Prepared by Carbopol 940 and characterized by Drug Content (98.730±0.259), Invitro Cumulative Drug Release (52.962 ±0.226 %). Dexamethasone released from the Plain Gel and permeated 13.499 in 8 hrs; niosomal formulations were able to delay the process up to 29.910 in 8 hrs. The skin permeation increase of dexamethasone was recorded from vesicle Gel in comparison to plain gel. The best fit correlation was found in the Zero order with the R 2 value of 0.997. Kinetic model described the release of drug in zero order

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The Exercise Attitudes, Perceptions, and Perceived Outcomes of Older Minority Women Participating in a Fall Prevention Program

The Exercise Attitudes, Perceptions, and Perceived Outcomes of Older Minority Women Participating in a Fall Prevention Program

Auditory sequential processing was measured using the Digit Span subtest from the Wechsler Memory Scales- 3 rd Edition (Psychological Corporation, 1997). The Digit Span subtest consists of two parts: Digit Span Forward and Backward. For each part, the examiner says a series of numbers at the rate of one number per second. The participant responds by either repeating the same series in the forward task or the reversed series in the backward task. For both parts of the subtest, the test begins with a series of two numbers and continues to add numbers to each progressive series until a maximum of a nine number series for Digit Span Forward and an eight number series for Digit Span Backward. Participants are given two trials of a series length, and the test continues until both trials of a series length are failed, or until they have completed every series. One point is awarded for each trial that the participant correctly answers. Test-retest reliability for the Digit Span subtest is .90 for 20-24 year-olds. Overall standard score, as well as longest forward digit span (longest number of digits correctly repeated forward) and backward span (longest number of digits correctly repeated backward) were calculated.

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Formulation and in vitro evaluation of Rifampicin Loaded Niosomes

Formulation and in vitro evaluation of Rifampicin Loaded Niosomes

to liposomes (lipid-based vesicles). Niosomes may overcome the problems associated with liposomes, one of which relates to the chemical instability of the constituent phospholipids. Due to their predisposition to oxidative degradation, phospholipids must be stored and handled in nitrogen atmosphere. The cost and variable purity of natural phospholipids also militate against adoption of liposomes as drug delivery vesicles [10, 11, 12]. Niosomes have been used for improving the stability of entrapped drug[13]; for detection of tumors [14]; and to modify the tissue distribution of entrapped harmine [15], proteins and biologicals products [16] terbinafine hydrochloride [17], colchicines[18], Acyclovir[19] methotrexate[10], salbutamol sulphate [5], propranolol HCL [20] methotrexate complexed with beta-Cyclodextrin [21], Aceclofenac [6] Erythromycin [7] griseofulvin [8] doxorubicicin [11] and ketoprofen [3].

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“Non-Ionic Surfactant Vesicles of Silymarin: Formulation Development and Evaluation” by Bhupendra Kumar, Mahasweta Roy, Nishant Kumar, Babita Kumar, Pradeep Kumar Tyagi, Kohinoor Khan, India.

“Non-Ionic Surfactant Vesicles of Silymarin: Formulation Development and Evaluation” by Bhupendra Kumar, Mahasweta Roy, Nishant Kumar, Babita Kumar, Pradeep Kumar Tyagi, Kohinoor Khan, India.

The present study was to prepare and evaluate niosomes of Silymarin using non ionic surfactants for targeted drug delivery system. Silymarin niosomes were prepared from Proniosomes, by using surfactants like span 40, span 60, span 80, tween 20, and tween 80 and were evaluated for physicochemical properties including particle size, entrapment efficiency, and in vitro drug release using ‘‘Franz diffusion cell’’ through goat intestine. Preformulation studies were performed to check the compatibility of drug and excipient and no interaction was found. A total of five formulation were developed (F1 to F5) and it was found that span80 formulation (F3) has best result for all the parameters as it had maximum entrapment of 80.45% among other five formulations followed by span60 formulation (F2) 74.21% entrapment efficiency. The in vitro drug release profile shows that span80 formulation (F3) have more sustained release profile as compare to other formulation, because %CDR (cumulative drug release) of F3 is 44.90% in 12 hours. The shape and surface morphology of niosomes were characterized by optical and Transmission electron microscopy. This study was also conducted to evaluate the hepatoprotective activity of Silymarin niosomes. Hepatotoxicity was induced by CCl 4

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