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Evaluation of the Effect of Critical Process and Formulation Parameters on the Attributes of Nanoparticles Produced by Microfluidics. Design of Experiments Approach for Optimisation of Process and Formulation Parameters Affecting the Fabrication of Nanocrystals of Poorly Water-Soluble Drug Using Anti-solvent Precipitation in Microfluidic
No full textAdvanced drug delivery systems have shown immense success through
nanotechnology which overcomes the challenges posed by large sized particles
such as poor solubility, bioavailability, absorption, and target-specific delivery.
This study focuses on nano sizing by application of microreactor technology and
nanoparticles to obtain polymeric particulate with a selection of model drugs for
inhalation drug delivery routes. The development of nanoparticles of two
challenging compounds in terms of solubility and permeability, namely
Ibuprofen (IBU) and Salmeterol (SAL), was conducted using a continuous,
controlled, and scalable system offered by microfluidic reactor with the
incorporation of anti-solvent approach. The research explores the potential of
this technology to enhance absorption rate and hence bioavailability of IBU via
oral route, and SAL via inhalation.
IBU, an anti-inflammatory drug, is classified as BCS Class II drug with low
solubility and high permeability. SAL is a selective long acting β2-agonist which
is co-dispensed along with a short-acting β2-agonist for quick relief of acute
bronchoconstriction due to its long onset of action. This lack of the ‘kick’ effect
in SAL can be attributed to its relatively higher lipophilicity which causes a delay
in the diffusion to the β2 receptors on the smooth muscles. It is therefore
feasible to assume that increasing the dissolution and/or diffusion rate of SAL in the interstitial fluids would reduce the delay between administration and the
onset of action of this drug which would be beneficial to patients.
Process and formulation parameters were investigated to optimize the
production and stability of nano particles of both drugs using Y shaped microfluidic reactors.
IBU results show that the smaller the angle between the two inlets were the
smaller the particle size achieved. Moreover, the particle size increased with
increasing the concentration of IBU solution. The effect of the polymer mixture
ratio (PVP/HPMC) on the initial particle size was not clear though. The smallest
particle size (113 nm) was achieved using 10° Y shaped chip with IBU
concentration of 1 mg/mL and a polymer mixture of 0.3% w/v PVP and 0.5%
w/v HPMC. Using a polymer mixture of 0.5% w/v of each polymer though
yielded a better PDI (140nm and PDI of 0.5).
Same observations were noted when the syringe pumps were replaced with a
non-pulsatile pressure pump. Particle size though dropped significantly to
33nm. Stability data showed that all systems were practically stable regardless
of the process or formulation parameters.
In addition, a considerable 2.5 fold increase in dissolution rate was observed in
the first 20 minutes when compared to the raw material.
The optimized parameters were applied to SAL to produce nanocrystals with
best result (59 nm) were obtained using 50µg/mL Salmeterol with microfluidics
inlet angle 10° with non-pulse syringe pump. The stabilizing mixture was PVP
0.8% w/v and Tween 80 at a concentration of 0.02%. This approach offered a
basis for the generation of nano sized SAL particles with higher fine particle fraction and better deposition in NGI than currently marketed formulations, thus
providing a more efficient drug dose delivery and lung deposition
Optimisation of semi-batch reactive distillation column for the synthesis of methyl palmitate
Get PDFYesSynthesis of methyl palmitate (MP) has not been considered in the past using a reactive distillation process (continuous or batch) due to the challenge of keeping the reactants palmitic acid (PA) and methanol (MeOH) together in the reactive zone. MeOH, being the lightest in the reaction mixture, travels up the distillation column as distillation proceeds and will be removed from the system via the distillate in a conventional batch reactive distillation (CBRD) column and thus will limit the conversion of PA. Therefore, in this work semi-batch reactive distillation (SBRD) column is proposed where additional methanol will be fed at the bottom of the column in a continuous mode allowing the chemical reaction to continue. However, as water (H2O) is one of the reaction products and is the second lightest component in the mixture, it will travel up the column next and will be removed in the distillate tank. Also due to wide difference in the boiling points of the reaction products and due to diminishing amount of water in the reboiler, the backward reaction will not be a dominating factor and therefore ignored in this work. With this backdrop, optimal performance of the SBRD column is evaluated in terms of conversion of PA to MP and energy consumption via minimization of the operating batch time for a wide range on MP purity
Modelling and simulation of industrial multistage flash desalination process with exergetic and thermodynamic analysis. A case study of Azzour seawater desalination plant
Get PDFYesDespite the fact of being intensive energy consumption, MSF is a mature technology that characterised by a high production capacity of high-quality water. The multistage flash (MSF) desalination process is one of the prominent thermal desalination used in the industry of seawater desalination to produce high quantity and high quality of freshwater. However, this process consumes large amount of energy and faces thermal limitations due to its high degree of exergy destruction at several units of the process. Therefore, the research of MSF is still existed to elevate the performance indicators and to resolve the concern of high energy consumption. To rectify these limitations, it is important to determine the units responsible in dissipating energy. This study aims to model an industrial MSF process validated against real data and then investigate the exergy destruction and thermodynamic limitations of the process. As a case study, Azzour MSF seawater desalination plant, located in Al Khiran in Kuwait is under the focus. A comprehensive model is developed by analysing several published models. Specifically, the calculation of exergy destruction has embedded both physical and chemical exergies that identified as a strong point of the model developed. As expected, the highest exergy destruction (55.5%) occurs within the heat recovery section followed by the brine heater with exergy destruction of 28.26% of the total exergy destruction. This study identifies the sections of the industrial process that cause the highest energy losses
The feasibility of patient reported outcome measures for the care of penile cancer
No full textYesWhen used in routine clinical practice, Patient Reported Outcomes Measures (PROMS) can give patients tacit approval to discuss embarrassing topics, which could be particularly useful for urological nursing. The aim of this study was to assess whether it would be feasible to use two such measures for penile cancer; one for body image (the Male Genital Self-Image Scale; MGSIS-5) and another for lymphedema (the Groin and Lower Limb Lymphedema questionnaire; G3L-20). Study packs were posted to penile cancer patients who had received (i) sentinel node biopsy only, (ii) inguinal node dissection only, and (iii) inguinal node dissection with post-operative radiotherapy with or without chemotherapy. The two measures (MGSIS-5 and G3L-20) were complemented with those specific to sexual function (IIEF) and cancer (EORTC-QLQ-C30 version 3) and a modified Lymphoedema Genitourinary Cancer Questionnaire (mLGUCQ). Twenty patients returned questionnaires. Validity and reliability analyses are presented but low participant numbers mean that results need treating with caution. Results show sufficient feasibility for the MGSIS-5 and the G3L-20 to warrant another study to attract larger numbers of participants, either over a longer time frame or at multiple sites. In these further studies, we would recommend adding (1) more Likert responses, (2) the timeframe to the MGIS and (3) exploring either the use of sexual desire psychometric measures or the addition of sexual desire items to the MGSIS for this patient group
Stem Cell Niche Microenvironment: Review
No full textYesThe cornea comprises a pool of self‐regenerating epithelial cells that are crucial to preserving clarity and visibility. Limbal epithelial stem cells (LESCs), which live in a specialized stem cell niche (SCN), are crucial for the survival of the human corneal epithelium. They live at the bottom of the limbal crypts, in a physically enclosed microenvironment with a number of neighboring niche cells. Scientists also simplified features of these diverse microenvironments for more analysis in situ by designing and recreating features of different SCNs. Recent methods for regenerating the corneal epithelium after serious trauma, including burns and allergic assaults, focus mainly on regenerating the LESCs. Mesenchymal stem cells, which can transform into self‐renewing and skeletal tissues, hold immense interest in tissue engineering and innovative medicinal exploration. This review
summarizes all types of LESCs, identity and location of the human epithelial stem cells (HESCs), reconstruction of LSCN, and artificial stem cells for self‐renewal
Green and Highly Efficient MIMO Transceiver System for 5G Heterogenous Networks
No full textYesThe paper presents the general requirements and an exemplary design of the RF front-end system that in today's handset is a key consumer of power. The design is required to minimize the carbon footprint in mobile handsets devices, whilst facilitating cooperation, and providing the energy-efficient operation of multi-standards for 5G communications. It provides the basis of hardware solutions for RF front-end integration challenges and offers design features covering energy efficiency for power amplifiers (PAs), Internet of Things (IoT) controlled tunable filters and compact highly isolated multiple-input and multiple-output (MIMO) antennas. An optimum design requires synergetic collaboration between academic institutions and industry in order to satisfy the key requirements of sub-6 GHz energy-efficient 5G transceivers, incorporating energy efficiency, good linearity and the potential for low-cost manufacturing. A highly integrated RF transceiver was designed and implemented to transmit and receive a picture using compact MIMO antennas integrated with efficient tunable filters and high linearity PAs. The proposed system has achieved a bit error rate (BER) of less than 10-10 at a data rate of 600 Mb/s with a wireless communication distance of more than 1 meter and power dissipation of 18-20 mW using hybrid beamforming technology and 64-QAM modulation.10.13039/100010665-H2020 Marie Skodowska Curi
The determinants of bank branch location in India: An empirical investigation
Get PDFYesBank branching plays a significant role in a wide range of economic activities. Existing studies on determinants of bank branching activities largely focus on developed countries, studies devoted to developing countries are scant. We present the first study that examines the determinants of bank branching activities in one of the largest developing country India.
We employ a unique longitudinal data to study the determinants of bank branch location in India. This data is collected at the state level covering 25 Indian states for the period 2006 to 2017. We employ Poisson regression that are better suited for modelling counted dependent variable.
First, region and bank specific factors such as size of population and bank deposits influence location of bank branches. Second, the relationship between these factors and branch locations is heterogeneous across different types of banks and across states with different business environments.
First, from the view of banks, considering the factors of branch location are crucial in order to set out branching strategy. Irrespective of policy measures aimed at promoting financial inclusion in India, we show that banks consider economic activities in the region in locating their branches. Second, from the view of policy makers and regulators, such branching strategy could potentially contribute to financial exclusion. As a result, population in the less developed regions may be excluded from accessing financial services. Hence, policy makers and regulators should take into this account when formulating policies aimed at promoting financial inclusion.
First, while existing studies largely focus on developed countries, studies devoted to developing countries are scant. To the best of our knowledge, we have not come across any study that investigates the determinants of bank branch location in India, so we reasonably believe that ours is a first-of-its-kind. Second, our study provides a new perspective concerning how regional and bank specific factors influence banks of different ownership in locating branches. Third, while traditional regression used to be a method of choice among early studies, we employ Poisson regression that are better suited for modelling counted dependent variable
A mussel-inspired antibacterial hydrogel with high cell affinity, toughness, self-healing, and recycling properties for wound healing
Get PDFYesAntibacterial hydrogels have been intensively
studied due to their wide practical potential in wound healing.
However, developing an antibacterial hydrogel that is able to
integrate with exceptional mechanical properties, cell affinity, and
adhesiveness will remain a major challenge. Herein, a novel
hydrogel with antibacterial and superior biocompatibility properties was developed using aluminum ions (Al3+) and alginate−
dopamine (Alg-DA) chains to cross-link with the copolymer chains
of acrylamide and acrylic acid (PAM) via triple dynamic
noncovalent interactions, including coordination, electrostatic
interaction, and hydrogen bonding. The cationized nanofibrillated
cellulose (CATNFC), which was synthesized by the grafting of
long-chain quaternary ammonium salts onto nanofibrillated
cellulose (NFC), was utilized innovatively in the preparation of antibacterial hydrogels. Meanwhile, alginate-modified dopamine
(Alg-DA) was prepared from dopamine (DA) and alginate. Within the hydrogel, the catechol groups of Alg-DA provided a decent
fibroblast cell adhesion to the hydrogel. Additionally, the multitype cross-linking structure within the hydrogel rendered the
outstanding mechanical properties, self-healing ability, and recycling in pollution-free ways. The antibacterial test in vitro, cell
affinity, and wound healing proved that the as-prepared hydrogel was a potential material with all-around performances in both
preventing bacterial infection and promoting tissue regeneration during wound healing processes.This work was supported by the National Natural Science Foundation of China (32070826 and 51861165203), the Chinese Postdoctoral Science Foundation (2019M650239, 2020T130762), the Sichuan Science and Technology Program (2019YJ0125), the State Key Laboratory of Polymer Materials Engineering (sklpme2019-2-19), the Chongqing Research Program of Basic Research and Frontier Technology (cstc2018jcyjAX0807), Chongqing Medical Joint Research Project of Chongqing Science and Technology Committee & Health Agency (2020GDRC017), and the RCUK China-UK Science Bridges Program through the Medical Research Council, and the Fundamental Research Funds for the Central Universities
The Automated Prediction of Solar Flares from SDO Images Using Deep Learning
Get PDFYesIn the last few years, there has been growing interest in near-real-time solar data processing, especially for space weather applications. This is due to space weather impacts on both space-borne and ground-based systems, and industries, which subsequently impacts our lives. In the current study, the deep learning approach is used to establish an automated hybrid computer system for a short-term forecast; it is achieved by using the complexity level of the sunspot group on SDO/HMI Intensitygram images. Furthermore, this suggested system can generate the forecast for solar flare occurrences within the following 24 h. The input data for the proposed system are SDO/HMI full-disk Intensitygram images and SDO/HMI full-disk magnetogram images. System outputs are the “Flare or Non-Flare” of daily flare occurrences (C, M, and X classes). This system integrates an image processing system to automatically detect sunspot groups on SDO/HMI Intensitygram images using active-region data extracted from SDO/HMI magnetogram images (presented by Colak and Qahwaji, 2008) and deep learning to generate these forecasts. Our deep learning-based system is designed to analyze sunspot groups on the solar disk to predict whether this sunspot group is capable of releasing a significant flare or not. Our system introduced in this work is called ASAP_Deep. The deep learning model used in our system is based on the integration of the Convolutional Neural Network (CNN) and Softmax classifier to extract special features from the sunspot group images detected from SDO/HMI (Intensitygram and magnetogram) images. Furthermore, a CNN training scheme based on the integration of a back-propagation algorithm and a mini-batch AdaGrad optimization method is suggested for weight updates and to modify learning rates, respectively. The images of the sunspot regions are cropped automatically by the imaging system and processed using deep learning rules to provide near real-time predictions. The major results of this study are as follows. Firstly, the ASAP_Deep system builds on the ASAP system introduced in Colak and Qahwaji (2009) but improves the system with an updated deep learning-based prediction capability. Secondly, we successfully apply CNN to the sunspot group image without any pre-processing or feature extraction. Thirdly, our system results are considerably better, especially for the false alarm ratio (FAR); this reduces the losses resulting from the protection measures applied by companies. Also, the proposed system achieves a relatively high scores for True Skill Statistics (TSS) and Heidke Skill Score (HSS)
The Impact of Risk Management on Project Success. A case study of the Land Administration Project, Ghana
Get PDFWhile previous research suggests that risk management influences project success, less is known about the practical application of the risk management concept on projects and its’ influence on development project success. Thus, this thesis investigates the impact of risk management on project success from a development project perspective. Adopting a qualitative case study approach with semi-structured interviews as the main source of data collection and assessing success from a stakeholder perspective as well as the achievements of the project’s intended outcomes and analysing the various risk management strategies adopted in the pursuance of those outcomes, the findings indicate that risk management practice positively influence development project success. To achieve this, the empirical data shows that risk identification need to be approached strategically to provide a clear focus for project delivery leading to the design of strategic actions to respond to identified risks as well as an effective monitoring and evaluation of the risk management process as a whole. Additionally, the different stakeholder objectives and expectations need to be strategically incorporated into the risk management strategy without deviating from the project’s purpose.
The study recommends the need for development project managers not to over-rely on academic expertise in their identification of risks but make use of the wider pool of knowledge available to them, technical or not and to also pursue the positive impacts of risk. Furthermore, they should widen their risk management strategies to include donor support missions, without deviating from the project’s purpose, to ensure transparency and efficiency