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IFRS 15 Intäkter från avtal med kunder : En undersökning om hur företagens affärsmodeller påverkar intäktsredovisningen under IFRS 15Milic, Katarina, Pettersson, Rebecka January 2019 (has links)
In the late 1990s and early 2000s several revenue recognition scandals arose, which led to a discussion about the need for a new principle-based standard with a balance sheet-based approach for revenue recognition. On 1st of January 2018 IFRS 15 Revenue from Contracts with Customers became effective and replaced all previous revenue recognition standards and interpretations. All companies are expected to be affected regarding when and how much the company reports its revenue, though the scope may vary from one company to another. This study aims to investigate how the application of IFRS 15 has impacted companies based on the business models they apply in their customer agreements. To operationalize the purpose of the study a quantitative method was adopted to gather the empirical data, which have been obtained from the companies’ annual reports. An enumeration was implemented, why all listed companies on Nasdaq Stockholm which are required to implement IFRS 15 have been studied. The results indicate that a minority of the companies have showed an impact and most of the companies have not been impacted after an implementation of the new revenue recognition standard. The study has identified that the reason why companies are affected by IFRS 15 depends on the business models’ companies apply in their customer agreements. The minority of companies that have been affected by IFRS 15 are the ones which have developed business models that includes complex customer contracts, i.e. customer contracts consisting of complex commitments and promises of goods and services to customers. Accordingly, the majority of the studied companies uses business models with non-complex customer contracts in their customer agreements, e.g. simple sale of only one good, hence their revenue recognition under IFRS 15 does not differ from previous accounting standards.
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Face-to-face, print-based or e-learning? A case study of ICT integration in alternative instructional modalities at the University of SwazilandNsibande, Gciniwe N 13 August 2015 (has links)
A thesis submitted in fulfilment of the requirements
of the degree of
DOCTOR OF PHILOSOPHY
SCHOOL OF EDUCATION
THE UNIVERSITY OF WITWATERSRAND
July, 2014 / This study seeks to establish key differences in pedagogical practices associated with and facilitated by different modalities of course delivery. These are: face-to-face instruction in a traditional university lecture-based environment; print-based course delivery, whereby off- campus distance learning students attend face-to-face lectures and tutorials on campus from time-to-time, and Moodle-based online course delivery integrated into the lecture and tutorial-based environments.
The key aspect of the study concerns changing pedagogy as a consequence of the introduction of online learning tools within the traditional delivery modalities. I investigate the nature of and extent to which a Moodle platform has been introduced into the traditional face-to-face teaching and learning situation. This is done to ascertain exactly how the pedagogies established and practiced within the traditional delivery modalities are recontextualised in the digital delivery modality. Recontextualisation in this context refers to how the curriculum and pedagogic practice are transformed when interpreted and delivered by instructors to both full-time and distance education students through the three teaching and learning delivery modalities used at UNISWA. The extent of the recontextualisation is accounted for through an experiential case study of four different instances in which the same course is taught by the same instructor to the two student groups. The content and aim of each course is identical, but the pedagogy is not intended by each instructor to be the same in each case. This scenario provided a distinctive, perhaps even unique, opportunity to study the recontextualisation of pedagogic content, pedagogic practices, and assessment practices in a controlled manner across the three modalities.
The research goal was realised by employing a multiple-case study design where four faculty staff members completed a 36 item Likert scales type questionnaire. On the basis of a content analysis of this limited quantitative data, each instructor was interviewed in-depth on their pedagogical practices to establish what lay beneath their beliefs in teaching and learning and espoused practices. Key themes were identified and continuous comparison was executed to analyse the transcribed questionnaire data against the interview data. I strengthened the qualitative aspect of this study by means of documentary analysis of course texts ranging from printed course learning materials, such as; course outlines, handouts, modules and Moodle web pages. I also conducted,
3
recorded and transcribed face-to-face as well as content and learning pathway (Moodle) observations, to once more contrast enacted pedagogic practice against espoused pedagogic beliefs.
I use Bernstein’s (1990, 2000) theory of pedagogic discourse extensively,particularly his notions of classification and framing principles. Weak classification (-C), specifically in the case of this study, means the more there is reference to online lessons, materials, assignments, feedback and so on or use of e-learning in face-to-face instruction,the more e-learning is integrated into the traditional modalities of teaching. In the same way, strong classification (+C) denotes that the more face-to-face and e-learning are kept apart, the less integration of e-learning into traditional modalities of teaching is taking place. Likewise, the framing principle relates to the transmission of knowledge through pedagogic practices. Strong framing (+F) is used to indicate a visible pedagogic practice that is traditional and therefore opposed to a constructivists approach expected when teaching distance education students and when using e-learning. Weak framing (-F) is applied to indicate an invisible pedagogic practice that is closely related to the mandated constructivist approach.
The research findings answered the research question of whether an instructor’s pedagogic practice remains unchanged whichever delivery modality is used. Bernstein’s classification and framing principles are employed to check and establish the instructor’s pedagogical practice and provide the framework for presenting the main findings of this study. With the exception of one out of four case study instructors, the practice is strong classification and framing (+C/F) throughout. This reflects that the traditional approach is predominantly applied in the classroom. This study thus recommends that multiple pedagogical approaches should be acknowledged and applied in all teaching and learning.
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Daňové trestné činy / Tax crimesBeltran, Simona-Estrella January 2021 (has links)
Tax Crimes Abstract The diploma thesis deals with tax crimes. The aim is to create a systematic overview and evaluation of the current criminal law of tax crimes in the legal order of the Czech Republic. The initial chapter focuses on the general definition of terms, including developmental stages of tax crimes, which mentions the reintroduction of criminality in the preparation of tax evasion, charge and similar mandatory payments in the Criminal Code in specific cases. The next chapter is devoted to a historical evolution into the development of tax crime legislation. The third chapter analyzes the legislative framework of the criminal law regulation of tax crimes in the Czech legal system. As part of the analysis of the crime tax fraud is explained how carousel fraud abusing the tax system within the EU works, as it is one of the most exploited tax evasions in the field of value added tax. This chapter also pays attention to the principle of nemo tenetur ipsum accusare in connection with taxation of income that originated from criminal activities. The next chapter deals with the prevention of tax evasion, with an emphasis on reverse-charge, which is based on the principle that the obligation to declare value added tax is transferred from the provider to its recipient. I follow up with the criminal...
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Implementeringen av EU:s tjänstedirektiv i svensk rätt : Principerna om god förvaltning i EU:s tjänstedirektiv och processuell autonomi vid implementering av direktivet i svensk rättHajdini, Adelina January 2022 (has links)
The aim of this study is to examine how Sweden has implemented directive 2006/123/EC of the European Parliament and of the council of 12 December 2006 on services in the internal market, in the framework of the member states procedural- and institutional autonomy. The study will focus on the contributions to the Swedish law in the form of expressions of the principle of good administration, as a result of the implementation of the directive. The expressions of the principle of good administration were found in the main law "Act (2009:1079) on services in the internal market" where the majority of the directive's provisions were implemented in Swedish law. The study focuses on two expressions of the principle that simultaneously are news in Swedish law induced by the implementation of The Services Directive: the principle of necessity and liaison points of the authorities. With basis in the study of the implementation of The Services Directive as an EU secondary law act in Swedish law and the new expressions of the principle of good administration in Swedish law to fulfill the directive - the purpose of the study will include an analysis of the EU-law's impact on Swedish Administrative Law with focus on the legislation's format. The analysis will, among other things, refer to the different administrative law traditions in the two legal systems regarding the status of general principles of law, mainly the principle of good administration, in the field of administrative law.
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An Argument For Non-Delegation?Marcum, Seth Allen 16 May 2017 (has links)
No description available.
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Numerical solutions to some ill-posed problemsHoang, Nguyen Si January 1900 (has links)
Doctor of Philosophy / Department of Mathematics / Alexander G. Ramm / Several methods for a stable solution to the equation $F(u)=f$ have been developed.
Here $F:H\to H$ is an operator in a Hilbert space $H$,
and we assume that noisy data $f_\delta$, $\|f_\delta-f\|\le \delta$, are given in place of the exact data $f$.
When $F$ is a linear bounded operator, two versions of the Dynamical Systems Method (DSM) with stopping rules of Discrepancy Principle type are proposed and justified mathematically.
When $F$ is a non-linear monotone operator, various versions of the DSM are studied.
A Discrepancy
Principle for solving the equation is formulated and justified. Several
versions of the DSM for solving the equation
are
formulated. These methods consist of a Newton-type method, a
gradient-type method, and a simple iteration method. A priori and a
posteriori choices of stopping rules for these methods are proposed and
justified. Convergence of the solutions, obtained by these methods, to
the minimal norm solution to the equation $F(u)=f$ is proved. Iterative
schemes with a posteriori choices of stopping rule corresponding to the
proposed DSM are formulated. Convergence of these iterative schemes to a
solution to the equation $F(u)=f$ is proved.
This dissertation consists of six chapters which are based on joint papers by the author and his advisor Prof. Alexander G. Ramm.
These papers are published in different journals.
The first two chapters deal with equations with linear and bounded operators and the last four chapters deal with non-linear equations with monotone operators.
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Formulation, in vitro release and transdermal diffusion of pravastatin by the implementation of the delivery gap principle / Cornel BurgerBurger, Cornel January 2014 (has links)
Active pharmaceutical ingredients (APIs), which are incorporated in different formulations, i.e. creams, gels, foams, etc., are applied to the skin for a therapeutic effect. This therapeutic effect could either be required in the top layer of the skin (topical drug delivery) or deeper layers to reach the blood capillaries (transdermal drug delivery). Transdermal delivery avoids oral administration route limitations, such as first pass metabolism which is the rapid clearance of the drug in the gastrointestinal tract and degradation by enzymes. This delivery targets the drugs to skin sites, where there are significant advantages which include: improved patient compliance, a steady drug delivery state, less frequent dosing, adverse effects are minimal, it is less invasive and issues with the gastrointestinal absorption are avoided by eliminating the first pass metabolism (Perrie et al., 2012:392). This type of delivery is not free from limitations even though the skin can be employed for targeted drug delivery and is a readily available and large accessible surface area for adsorption of drugs. The most upper layer of the human skin, the stratum corneum, which is a watertight barrier, offers defence against hazardous exterior materials such as fungi, allergens, viruses and other molecules. This indicates the stratum corneum controls the drug penetration of most drugs to permeate the skin barrier (Lam & Gambari, 2014:27).
Pravastatin is hydrophilic and is a 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitor which inhibits cholesterol synthesis, a rate-limiting step, in the liver, thus decreasing the level of plasma low density lipoprotein cholesterol (LDL-C) (Heath et al., 1998:42). It can also slow the progression of atherosclerosis and can lower the incident of coronary events (Haria & McTavish, 1997:299).
The first aim of the study is to deliver pravastatin transdermally into the blood circulation. Currently, pravastatin is only administered in oral dosages and can cause highly negative adverse effects such as myopathy and increased liver enzymes. This increase in liver enzymes causes hepatotoxicity and therefore would be ideal if pravastatin could be delivered transdermally, as the first pass metabolic effect would be nullified and adverse effects would decrease drastically (Gadi et al., 2013:648).
Prof JW Wiechers‟ Delivery Gap Principle was designed in attempt to effectively enhance transdermal drug delivery. This Delivery Gap Principle was incorporated in the computer programme he developed known as “Formulating for Efficacy” (FFE™). The transdermal delivery of suggested APIs, which in this case is pravastatin, when incorporated into a formulation, may be optimised transdermally. The FFE™ computer programme suggests that the oil phase can be optimised, which in turn leads to better permeation through the skin to the target site (transdermal). The formula can be manipulated to reach desired polarity.
The second aim of this in vitro study was to investigate the implementation of Wiechers‟ Delivery Gap Principle in a semi-solid dosage form, for the transdermal delivery of pravastatin sodium (2%).
Six formulations, of which three were cream and three were emulgel formulations incorporated with pravastatin sodium (2%), were formulated. Each formulation had a different polarity, i.e. hydrophilic cream (HC) and emulgel (HE), lipophilic cream (LC) and emulgel (LE) and optimised cream (OC) and emulgel (OE).
A high performance liquid chromatography (HPLC) method was developed and validated to analyse the concentration of pravastatin. Both the octanol-buffer distribution coefficient (log D) and the aqueous solubility of pravastatin were determined.
For the API to permeate through the skin into the blood circulation, certain physicochemical properties are important and according to Naik et al (2000:321), there are specific ideal limits for the API in the formulations which include log D (1 to 3) and a aqueous solubility of >1 mg/ml. The aqueous solubility of 197.5 mg/ml in phosphate buffer solution (PBS) (pH 7.4) at a temperature of 32 °C indicated penetration was favourable (Naik et al., 2000:321), whilst the log D value of -0.703 indicated the API was unfavourable for skin penetration (Naik et al., 2000:321).
Membrane release studies were conducted using a synthetic membrane to determine whether pravastatin was released from the six formulations each containing 2% pravastatin prior to diffusion studies with. The OE yielded the highest median flux value (7.175 μg/cm2.h), followed the by LE (6.401 μg/cm2.h), HE (6.355 μg/cm2.h), HC (5.061 μg/cm2.h), OC (4.297 μg/cm2.h) and lastly, LC (3.115 μg/cm2.h). By looking at the aforementioned data values, it was concluded that the emulgels performed better than the cream formulations when median flux values were compared.
By using dermatomed excised female Caucasian skin, an execution of Franz cell diffusion studies were performed over a period of 12 h, followed by a tape-stripping experiment to determine which semi-solid formulation delivered pravastatin best on the skin and the results of the different polarity formulations were compared.
The median amount per area which permeated through the skin after 12 h was as follows: the OE formulation (2.578 μg/cm2) depicted the highest median amount per area, followed by OC (1.449 μg/cm2), HC (0.434 μg/cm2), LE (0.121 μg/cm2), HE (0.055 μg/cm2) and lastly LC (0.000 μg/cm2). These results validate Wiechers` theory that when the oil phase is optimised, with regard to the same polarity as the skin, permeation will be enhanced (Wiechers, 2011).
During both the membrane studies and the skin diffusion studies it was evident the emulgel formulations performed better and pravastatin permeated better than the cream formulations. When skin diffusion and membrane median data values were compared, it was evident in both the membrane release studies and the skin diffusion studies that OE yielded the highest median values and LC the lowest median values. It was clear that all six different formulations released pravastatin, but LC displayed no permeation into the systemic circulation (receptor phase).
The data of the different polarity formulations which yielded the best results with regards to median concentrations within the stratum corneum-epidermis and epidermis-dermis, were identified and are: within the stratum corneum-epidermis, HE (1.448 μg/ml) yielded the highest median concentration pravastatin, followed by LE (1.301 μg/ml), LC (0.676 μg/ml), HC (0.505 μg/ml), OE (0.505 μg/ml) and lastly OC (0.400 μg/ml). As emulgels (hydrophilic) contain more water than creams (lipophilic), the penetration enhancement effect can be explained by hydration, since the water hydrated the skin leading the lipids to open and the stratum corneum to swell (Williams & Barry, 2004:606). Therefore more API could permeate into the skin.
Within the epidermis-dermis the highest median concentration median was yielded by OE (0.849 μg/ml), followed by LC (0.572 μg/ml), HC (0.524 μg/ml), OC (0.355 μg/ml), HE (0.309 μg/ml) and lastly LE (0.138 μg/ml). Different polarity formulations permeating the viable epidermis could be a result of the solubility characteristics of the formulations. It contained both lipid properties (formulations contained oil content), leading to permeation through the stratum corneum and aqueous properties, which lead to diffusion into the underlying layers of the epidermis (Perrie et al., 2012:392).
According to Perrie (2012:392), formulations that need to be delivered transdermally, must permeate through the lipophilic stratum corneum and thereafter the hydrophilic dermal layers to reach the blood circulation, which means formulations must consist of both lipophilic and aqueous solubility properties. When comparing the stratum corneum-epidermis (lipophilic) with the epidermis-dermis (more hydrophilic) and receptor phase (hydrophilic; systemic circulation), it is evident that all formulations had lipophilic and hydrophilic properties, as the API permeated through the stratum corneum and penetrated the deeper layers of the skin (viable epidermis)
When all polarity formulations were compared, i.e. optimised, hydrophilic and lipophilic, it was observed that the optimised formulations depicted the highest median concentration values in the receptor phase (skin diffusion), but lowest median concentration in stratum corneum-epidermis, therefore the optimised formulation permeated best through the stratum corneum-epidermis. The reason for this could be that the optimised formulations had the same polarity as the skin (17, 8, 8), thus permeating through the skin to the receptor fluid more efficiently (Wiechers, 2011). It was observed that LC penetrated both stratum corneum-epidermis and epidermis-dermis, but did not permeate through the skin to the receptor fluid (systemic circulation), making it a good delivery vehicle for topical delivery.
Overall when the emulgel and cream formulations are compared, according to their ability to deliver pravastatin transdermally, it is evident the pravastatin diffused more from the emulgel formulations than the cream formulations. This could be due to the fact that emulgels are more hydrophilic as they contain more water, resulting in the emulgels diffusing to the deeper layers of the skin (more hydrophilic viable epidermis) (Benson, 2005:28).
All formulations contained not only aqueous (hydrophilic) but also lipid (lipophilic) solubility properties, therefore making it lipophilic enough to permeate the stratum corneum and hydrophilic enough to penetrate to deeper skin layers (viable epidermis) (Perrie et al., 2012:392). All formulations could still permeate the viable epidermis despite different polarities being used and all were appropriate candidates, although some were more suitable than others.
The understanding from this study is that:
* pravastatin could be delivered topically by all formulations,
* the best formulation to reach the systemic formulation is the optimised emulgel,
* the best formulation to deliver pravastatin topically is the hydrophilic emulgel. / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2015
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Formulation, in vitro release and transdermal diffusion of pravastatin by the implementation of the delivery gap principle / Cornel BurgerBurger, Cornel January 2014 (has links)
Active pharmaceutical ingredients (APIs), which are incorporated in different formulations, i.e. creams, gels, foams, etc., are applied to the skin for a therapeutic effect. This therapeutic effect could either be required in the top layer of the skin (topical drug delivery) or deeper layers to reach the blood capillaries (transdermal drug delivery). Transdermal delivery avoids oral administration route limitations, such as first pass metabolism which is the rapid clearance of the drug in the gastrointestinal tract and degradation by enzymes. This delivery targets the drugs to skin sites, where there are significant advantages which include: improved patient compliance, a steady drug delivery state, less frequent dosing, adverse effects are minimal, it is less invasive and issues with the gastrointestinal absorption are avoided by eliminating the first pass metabolism (Perrie et al., 2012:392). This type of delivery is not free from limitations even though the skin can be employed for targeted drug delivery and is a readily available and large accessible surface area for adsorption of drugs. The most upper layer of the human skin, the stratum corneum, which is a watertight barrier, offers defence against hazardous exterior materials such as fungi, allergens, viruses and other molecules. This indicates the stratum corneum controls the drug penetration of most drugs to permeate the skin barrier (Lam & Gambari, 2014:27).
Pravastatin is hydrophilic and is a 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitor which inhibits cholesterol synthesis, a rate-limiting step, in the liver, thus decreasing the level of plasma low density lipoprotein cholesterol (LDL-C) (Heath et al., 1998:42). It can also slow the progression of atherosclerosis and can lower the incident of coronary events (Haria & McTavish, 1997:299).
The first aim of the study is to deliver pravastatin transdermally into the blood circulation. Currently, pravastatin is only administered in oral dosages and can cause highly negative adverse effects such as myopathy and increased liver enzymes. This increase in liver enzymes causes hepatotoxicity and therefore would be ideal if pravastatin could be delivered transdermally, as the first pass metabolic effect would be nullified and adverse effects would decrease drastically (Gadi et al., 2013:648).
Prof JW Wiechers‟ Delivery Gap Principle was designed in attempt to effectively enhance transdermal drug delivery. This Delivery Gap Principle was incorporated in the computer programme he developed known as “Formulating for Efficacy” (FFE™). The transdermal delivery of suggested APIs, which in this case is pravastatin, when incorporated into a formulation, may be optimised transdermally. The FFE™ computer programme suggests that the oil phase can be optimised, which in turn leads to better permeation through the skin to the target site (transdermal). The formula can be manipulated to reach desired polarity.
The second aim of this in vitro study was to investigate the implementation of Wiechers‟ Delivery Gap Principle in a semi-solid dosage form, for the transdermal delivery of pravastatin sodium (2%).
Six formulations, of which three were cream and three were emulgel formulations incorporated with pravastatin sodium (2%), were formulated. Each formulation had a different polarity, i.e. hydrophilic cream (HC) and emulgel (HE), lipophilic cream (LC) and emulgel (LE) and optimised cream (OC) and emulgel (OE).
A high performance liquid chromatography (HPLC) method was developed and validated to analyse the concentration of pravastatin. Both the octanol-buffer distribution coefficient (log D) and the aqueous solubility of pravastatin were determined.
For the API to permeate through the skin into the blood circulation, certain physicochemical properties are important and according to Naik et al (2000:321), there are specific ideal limits for the API in the formulations which include log D (1 to 3) and a aqueous solubility of >1 mg/ml. The aqueous solubility of 197.5 mg/ml in phosphate buffer solution (PBS) (pH 7.4) at a temperature of 32 °C indicated penetration was favourable (Naik et al., 2000:321), whilst the log D value of -0.703 indicated the API was unfavourable for skin penetration (Naik et al., 2000:321).
Membrane release studies were conducted using a synthetic membrane to determine whether pravastatin was released from the six formulations each containing 2% pravastatin prior to diffusion studies with. The OE yielded the highest median flux value (7.175 μg/cm2.h), followed the by LE (6.401 μg/cm2.h), HE (6.355 μg/cm2.h), HC (5.061 μg/cm2.h), OC (4.297 μg/cm2.h) and lastly, LC (3.115 μg/cm2.h). By looking at the aforementioned data values, it was concluded that the emulgels performed better than the cream formulations when median flux values were compared.
By using dermatomed excised female Caucasian skin, an execution of Franz cell diffusion studies were performed over a period of 12 h, followed by a tape-stripping experiment to determine which semi-solid formulation delivered pravastatin best on the skin and the results of the different polarity formulations were compared.
The median amount per area which permeated through the skin after 12 h was as follows: the OE formulation (2.578 μg/cm2) depicted the highest median amount per area, followed by OC (1.449 μg/cm2), HC (0.434 μg/cm2), LE (0.121 μg/cm2), HE (0.055 μg/cm2) and lastly LC (0.000 μg/cm2). These results validate Wiechers` theory that when the oil phase is optimised, with regard to the same polarity as the skin, permeation will be enhanced (Wiechers, 2011).
During both the membrane studies and the skin diffusion studies it was evident the emulgel formulations performed better and pravastatin permeated better than the cream formulations. When skin diffusion and membrane median data values were compared, it was evident in both the membrane release studies and the skin diffusion studies that OE yielded the highest median values and LC the lowest median values. It was clear that all six different formulations released pravastatin, but LC displayed no permeation into the systemic circulation (receptor phase).
The data of the different polarity formulations which yielded the best results with regards to median concentrations within the stratum corneum-epidermis and epidermis-dermis, were identified and are: within the stratum corneum-epidermis, HE (1.448 μg/ml) yielded the highest median concentration pravastatin, followed by LE (1.301 μg/ml), LC (0.676 μg/ml), HC (0.505 μg/ml), OE (0.505 μg/ml) and lastly OC (0.400 μg/ml). As emulgels (hydrophilic) contain more water than creams (lipophilic), the penetration enhancement effect can be explained by hydration, since the water hydrated the skin leading the lipids to open and the stratum corneum to swell (Williams & Barry, 2004:606). Therefore more API could permeate into the skin.
Within the epidermis-dermis the highest median concentration median was yielded by OE (0.849 μg/ml), followed by LC (0.572 μg/ml), HC (0.524 μg/ml), OC (0.355 μg/ml), HE (0.309 μg/ml) and lastly LE (0.138 μg/ml). Different polarity formulations permeating the viable epidermis could be a result of the solubility characteristics of the formulations. It contained both lipid properties (formulations contained oil content), leading to permeation through the stratum corneum and aqueous properties, which lead to diffusion into the underlying layers of the epidermis (Perrie et al., 2012:392).
According to Perrie (2012:392), formulations that need to be delivered transdermally, must permeate through the lipophilic stratum corneum and thereafter the hydrophilic dermal layers to reach the blood circulation, which means formulations must consist of both lipophilic and aqueous solubility properties. When comparing the stratum corneum-epidermis (lipophilic) with the epidermis-dermis (more hydrophilic) and receptor phase (hydrophilic; systemic circulation), it is evident that all formulations had lipophilic and hydrophilic properties, as the API permeated through the stratum corneum and penetrated the deeper layers of the skin (viable epidermis)
When all polarity formulations were compared, i.e. optimised, hydrophilic and lipophilic, it was observed that the optimised formulations depicted the highest median concentration values in the receptor phase (skin diffusion), but lowest median concentration in stratum corneum-epidermis, therefore the optimised formulation permeated best through the stratum corneum-epidermis. The reason for this could be that the optimised formulations had the same polarity as the skin (17, 8, 8), thus permeating through the skin to the receptor fluid more efficiently (Wiechers, 2011). It was observed that LC penetrated both stratum corneum-epidermis and epidermis-dermis, but did not permeate through the skin to the receptor fluid (systemic circulation), making it a good delivery vehicle for topical delivery.
Overall when the emulgel and cream formulations are compared, according to their ability to deliver pravastatin transdermally, it is evident the pravastatin diffused more from the emulgel formulations than the cream formulations. This could be due to the fact that emulgels are more hydrophilic as they contain more water, resulting in the emulgels diffusing to the deeper layers of the skin (more hydrophilic viable epidermis) (Benson, 2005:28).
All formulations contained not only aqueous (hydrophilic) but also lipid (lipophilic) solubility properties, therefore making it lipophilic enough to permeate the stratum corneum and hydrophilic enough to penetrate to deeper skin layers (viable epidermis) (Perrie et al., 2012:392). All formulations could still permeate the viable epidermis despite different polarities being used and all were appropriate candidates, although some were more suitable than others.
The understanding from this study is that:
* pravastatin could be delivered topically by all formulations,
* the best formulation to reach the systemic formulation is the optimised emulgel,
* the best formulation to deliver pravastatin topically is the hydrophilic emulgel. / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2015
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THE STATUS OF THE PROJECTION PRINCIPLE IN GOVERNMENT-BINDING THEORYVinger, Gift January 2008 (has links)
Published Article / The role of the Projection Principle within Chomsky's Government-Binding
(GB) Theory is to preserve the subcategorisation properties of lexical items at
all levels of syntactic representation, viz. D-structure, S-structure, and Lexical
Form. Arguments have been made that the Projection Principle is a new
concept that is simply an extension of theTransformational Component (XFM)
and Emonds' Structure-Preserving Constraint (SPC), and that it does not
deserve the high status it has been accorded in GB theory. This paper
provides evidence, based on sentences involving movement operations, that
the Projection Principle is innovative and that it convincingly addresses what
theXFMandSPChave failed to address.
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THE TIMELINESS OF ASYNCHRONOUS PACKET MULTIPLEXING IN SWITCHED ETHERNETQiao, Li, XiaoLin, Zhang, Huagang, Xiong, Yuxia, Fei 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / Powered by single-segment switched interconnection, Ethernet can be used in time-critical data
acquisition applications. Unlike synchronous time division multiple access, asynchronous packet
streams result in congestions and uncertain multiplexing delays. With the delay analysis in the worst
case and probabilistic guaranteeing conditions, we restrict the packet-sizes, intervals or traffic
burstiness a priori to regulate delay deviations within acceptable scales. Some methods of
combinatorics and stochastic theory, e.g. Cumulant Generating Function and the Large Deviation
Principle, are used and verified by some simulation-based computations. The influence of time
varying delay for telemetry applications is also discussed in some sense.
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