1,721,271 research outputs found
Service marketing overview of RFL export department
Full text linkThis internship report is submitted in a partial fulfillment of the requirements for the degree of Master of Business Administration, 2015.Cataloged from PDF version of Internship reportIncludes bibliographical references (page 34)Md. Ariful Islam Bappy,M. Business Administratio
Equilibrium and Mass Transfer Behaviour of CO2 Adsorption on Zeolites, Carbon Molecular Sieve, and Activated Carbons
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research in Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Process Systems Engineering, University of Regina. xiv, 106 p.Natural gas is an important source of energy that usually requires purification steps
to remove contaminants prior to pipeline transmission and industrial usage. By pressure
swing adsorption process (PSA), carbon dioxide (CO2) can be separated from natural gas
using solid materials commonly known as adsorbents. Adsorption capacity (or
equilibrium) and adsorption kinetics of the adsorption materials have great impacts on the
efficiency of CO2 removal in this PSA process. The objective of this study was to
characterize the CO2 adsorption equilibrium and kinetics of commercial adsorbents that
have potential for use in the PSA process and also to provide a better understanding of
CO2 adsorption behaviour under wide range of operating conditions.
A comprehensive set of data and analysis for CO2 adsorption equilibrium and
kinetics is presented in this study for zeolite 13x, zeolite 5A, zeolite 4A, carbon
molecular sieve (MSC-3R), activated carbon (GCA-830), and activated carbon (GCA-
1240). By using volumetric measurement technique, adsorption equilibrium and kinetic
data were taken at a temperature range of 293 – 333 K and pressure up to 35 atm. The
obtained experimental data were correlated as a function of temperature and pressure to
fit with different model equations (i.e., Langmuir, Toth, Sips, and Prausnitz). The
isosteric heat of CO2 adsorption was also estimated for individual adsorbents according to
the Clausius-Clapeyron equation. The CO2 adsorption kinetic, presented in terms of mass
transfer coefficients (k), were experimentally measured at a temperature range of 293 –
333 K and pressure up to 11 atm. The mass transfer was analyzed from the plots of CO2
uptake rate using the well-recognized linear driving force (LDF) model. The mass transfer coefficients were correlated by non-linear regression to reveal the effects of
adsorption temperature and pressure. Activation energies of CO2 adsorption on the
individual adsorbents were also calculated and correlated according to the Arrhenius
equation.Studentye
Fatty acid binding protein 3(FABP3) regulates n-3 and n-6 polyunsaturated fatty acids(PUFAs) transportation in mouse trophoblast
No full text博士(医学)山口大学Yamaguchi Universit
Bioprinting and characterization of medium viscosity alginate scaffold for nerve tissue regeneration
Full text linkInjured peripheral nerves with a gap >2mm often demonstrate poor regeneration ability, where scaffolds made from biomaterials are possibly used to bridge the gap for functional recovery. To fabricate such scaffolds, extrusion-based three dimensional (3D) printing technique shows promising due to its ability to precisely extrude biomaterial solution and build 3D structures by a layer-by-layer fashion. However, the 3D printing technique faces several challenges in fabricating scaffolds for nerve tissue regeneration. Among them, the printability, structural integrity, and biological performance of scaffolds printed from sodium alginate (SA) (a biomaterial widely used in nerve tissue regeneration) are the key issues. To address the issues, this thesis aims to develop SA scaffolds for potential application in peripheral nerve regeneration. Three specific objectives are set so as to investigate (1) the effect of fluid (i.e., SA solution) flow behavior, printing parameters, and concentration of ionic crosslinkers on the printability of SA scaffolds, (2) the influence of SA precursor and ionic crosslinker concentrations on the mechanical and biological properties of scaffolds, and (3) the influence of peptide conjugation with SA molecules on the biological performance of the scaffolds for nerve tissue regeneration.
The flow rate in the printing process is critical to the scaffold structure and printability. The first part of dissertation is to examine the flow rate of SA solution or precursor extruded through a tapered needle in the scaffold fabrication process by developing a novel model for its representation. Specifically, the flow rate of the medium viscosity SA precursor was modeled by taking into account of both slip and shear flow from a tapered needle. Since the flow rate of SA precursor depends on its flow behavior, model predicting the flow behavior of the hydrogel precursor was also developed from regression of experimental data. For different extrusion pressures (e.g. 20, 25, 30, and 40 kPa) and concentrations (e.g. 2, 3, and 4%) of SA precursor, the flow rate model predicted with reasonable accuracy (coefficient of determination, R2 = 0.98). Further, at various needle diameters (0.2, 0.25, 0.41, and 0.61 mm) and temperatures (25, 35, 45, and 55°C) the flow rate model predicted more accurately for low dispensing pressure (20 kPa, R2=0.99) compared to high pressure (30 kPa, R2=0.98).
The mechanical and biological properties of SA scaffold largely depend on the ionic crosslinker used in bioprinting of scaffolds from SA. The second part of dissertation is to conduct a comparative study of three ionic crosslinkers including calcium chloride (CaCl2), barium chloride (BaCl2), and zinc chloride (ZnCl2) on the mechanical and biological properties of 3D printed SA scaffolds. Multiple regression equations were developed to predict the mechanical properties of SA scaffolds; and the printability of SA precursor was evaluated at varying concentrations of both ionic crosslinkers and SA precursor. Experimental results revealed that the elastic modulus of the hydrogels decreasing in the order BaCl2>CaCl2>ZnCl2 over 42 days while Schwann cell (SC) viability decreased in the order CaCl2>BaCl2>ZnCl2 over 7 days. The predictions of multiple regression equations show reasonable agreement with experimental data, while the 3% (w/v) SA precursor demonstrates acceptable printability in CaCl2 and BaCl2 solution. The experimental and predicted results obtained in this part of work would be useful in selecting the appropriate ionic crosslinkers and concentration of SA precursor for bioprinting of tissue scaffolds.
Notably, SA precursor lacks of cell binding motifs in the molecular structure, which significantly limits its applications in nerve tissue regeneration. For improvement, the third part of dissertation is to conjugate peptide molecules into SA, resulting in peptide conjugated SA (PCSA) and to further examine the effect of single and composite PCSA scaffolds on axon regeneration in vitro. In particular, a 2% (w/v) SA precursor was conjugated with either arginine-glycine-aspartate (RGD) or tyrosine-isoleucine-glycine-serine-arginine (YIGSR) peptides, or mixture of RGD and YIGSR (1:2), and was bioprinted into cuboid structures. The printability of the composite PCSA precursor was evaluated in terms of the strand width, pore geometry, and angle-formation accuracy at varying concentration of CaCl2 (i.e. 50 - 150 mM); and the mechanical stability of scaffolds was examined over 3 weeks in terms of swelling, degradation, and compression modulus; and surface morphology of the degraded scaffolds. Axon regeneration ability of PCSA scaffolds were assessed by quantifying the viability, morphology, amount of secreted brain derived neurotrophic factor (BDNF) of incorporated SCs, and directional neurite outgrowth in a 2D culture. Experimental results reveal that composite PCSA precursor extruded in 50 mM CaCl2 has good printability and that PCSA scaffolds remains porous over 3 weeks with the elastic modulus decreased by ~70%. Also, the results illustrates that composite PCSA scaffolds facilitate better the viability and morphology of SCs, as well as support greater directional neurite outgrowth as compared to those of single PCSA scaffolds.
Taken together, the thesis develops methods to fabricate SA and PCSA scaffolds with results illustrating their potential applications in the regeneration of damaged peripheral nerves
Data-centric explanations: Explaining training data of machine learning systems to promote transparency
No full textTraining datasets fundamentally impact the performance of machine learning systems. Any biases introduced during training (implicit or explicit) are often reflected in the system’s behaviors leading to questions about fairness and loss of trust in the system. Yet, information on training data is rarely communicated to the stakeholders. In this thesis, I explore the concept of data-centric explanations for machine learning systems that describe the training data to end-users. I design data-centric explanations that focus on providing information on training data. Through a formative study, I investigate the potential utility of such an approach and the data-centric information that users find most compelling. In a second study, I investigate reactions to the explanations across four different system scenarios. The results show that data-centric explanations can impact how users judge the trustworthiness of a system and can assist users in assessing fairness. I discuss the implications of the findings for designing explanations to support users’ perception of machine learning systems.February 202
Unconstitutional Constitutional Amendments in South Asia: A Study of Constitutional Limits on Parliaments’ Amending Power
Full text linkAgainst the backdrop of the landscape of Parliamentary Supremacy of south asian countries, members of parliament often cross their limit by thinking parliament as a sovereign body to make unnecessary constitutional amendments which are ultimately questioned by the courts. As a member of the legislative department, I unmasked the reasons behind this unauthorized exercise of power to stop the mockery of parliamentary democracy.Supreme Courts in south Asia are often asked to judge constitutionality of constitutional amendments which provides them with the opportunity to engage with the noble issue of ‘constitutional limits on parliamentary amending power’. Constitutional courts and commentators have always recognized some short of constitutional limits on parliament’s power to amend the constitution, though the nature and scope of such limits have been a matter of controversy. Courts in South Asia are divided in their opinion. While Court in Bangladesh and India invoked implied substantive constitution limits in parliamentary amending power and declared constitutional amendment unconstitutional in number of occasions, Courts in Srilanka and Pakistan have refused to do so. This study aims to examine the extent and nature of constitutional limits on parliamentary amending power with reference to the constitutional amendments, if any, so far declared by the constitutional courts in South Asia. However, for space constraint and other limits, we will confine ourselves to considering only the constitutional amendments, if any, so far declared unconstitutional in India Pakistan and Bangladesh. For the purpose this study, we will rely heavily on the jurisprudence developed by the Supreme Courts of Pakistan, India and Bangladesh in amendment cases, and on some fascinating academic literatures written by various constitutional commentators which directly address the position of the courts in these cases.Instead of discussing all the constitutional amendment cases in fragment, this paper will concentrate on studying various constitutional limits invoked by the courts on parliamentary amending power and opinions of the courts in those amendment cases will be referred in cases they are necessary in theoretical discussion of various constitutional limits. However, we will not go to see the procedural limits on amending power prescribed by the constitution itself, in that such limits being expressed in the provisions of the constitution are less controversial and does not merit much theoretical discussion. An attempt will be made to conceptualize the very concept of ‘unconstitutional constitutional amendment’. In this section we will look how the concept emerged in the jurisdictions beyond South Asia. Then will turn to see how South Asian courts in constitutional amendment cases have understood the concept. Conceptualizing unconstitutional constitutional amendment, we will turn to see the constitutional limits which are generally imposed on parliamentary amending power. In this regard, our focus will be to see various substantive constitutional limits invoked by the courts in India, Pakistan and Bangladesh. However details of such limits will be discussed in other appropriate sections dedicated for that purpose.Will have a short discussion on the definition of the term ‘amendment’ and examine if there is any limitation inherent in the term. It will be shown examination of the meaning of the term has greater importance in determining the scope of parliamentary amending power, as the court relied heavily in amendment cases on definition of the term to reach their conclusion. Examination of the positions of the courts in this regard will show that there are some inherent limits in the term ‘amendment’ which will considerably limit the power of parliament to amend the constitution. In next section, limit on amending the basic features of the constitution will be discussed. The doctrine of basic structure doctrine will be examined as it is invoked by the courts in India, Bangladesh and Pakistan. A part will be dedicated to address some core criticisms which basic structure doctrine is often to face. At last part of the section, we will turn to see to what extent basic structure provisions are immuned form amendment.We will examine the level of entrenchment enjoyed by fundamental rights against constitutional amendment. Firstly, position of the courts regarding the question- whether fundamental rights are law for the purpose of fundamental rights review- will be examined. Then attempt will be made to see what extent fundamental rights provisions are immured from amendment as one of the basic features of the constitution.In later section we will consider the limit, invoked by the courts in basic structure cases, on radical change of the constitution so that constitutional identity and purpose are not lost. A brief discussion of the concept of constitutional identity with its components will be given in this section.Legitimacy of the constitutional limits on amending power will be considered in the light of various constitutional theories such as constitutionalism, democracy, sovereignty, parliamentary sovereignty and popular sovereignty. While the limits will be judged in the lights of some fundamental constitutional and political concepts, focus will be placed to see how the constitutional limits on constitutional amendment challenged theses theories and to what extent we are forced to rethink those principle or concepts. .We then will turn to see ‘what the constitution is’ and how scope of amendment invariably depends on how one take the constitution to be. It will be seen that difference in views of the judges regarding nature of constitution ultimately leads them to vary in their positions as to constitutional limits on parliamentary amending power. In the last section we will turn into the interpretative attitudes adopted by the court to support their position as regard constitutional limits. It is because, without examining the mode of interpretation which helps to base the limitations and the theories which support and contradict such limitation, nature and extent of the limits cannot be understood properly. Keywords: Parliament, Unconstitutional, Amendment, Supreme Cour
Psychological Adjustment of Jagannath University Students Living with Family and without Family
No full textThe study aimed to investigate the psychological adjustment of Jagannath University (JNU) students living with family and without family. The study sample consisted of 100 students from different departments of Jagannath University. Among them, 50 students are living with family, where 25 were male and 25 were female, and from 50 students who are living without family, where 25 were male and 25 were female, all of whom have completed answering the Personality Assessment Questionnaire (Adult PAQ) (Uddin and Ahmed, 2012). The data obtained in the present study were analyzed using an independent sample t-test and Pearson product-moment correlation. The results reveal there is a significant difference between psychological adjustment and family coexistence, and they are significantly positively correlated (r=.687**; p<.05). The results also showed that living with family students (M=1.377) is more adjusted than living without family students (M=1.711). These results suggest that living with family, students have better psychological adjustment than living without family.
Keywords: Psychological adjustment, living with family, living without family
Fatty acid binding protein 3(FABP3) regulates n-3 and n-6 polyunsaturated fatty acids(PUFAs) transportation in mouse trophoblast
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