949 research outputs found
Results on -continuous graphs
summary:For any nontrivial connected graph and any graph , the {\it -degree} of a vertex in is the number of copies of in containing . is called {\it -continuous} if and only if the -degrees of any two adjacent vertices in differ by at most 1; is {\it -regular} if the -degrees of all vertices in are the same. This paper classifies all -continuous graphs with girth greater than 3. We show that for any nontrivial connected graph other than the star , , there exists a regular graph that is not -continuous. If is 2-connected, then there exists a regular -continuous graph that is not -regular
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Learning and skills development in a fragmented industry. The case of the UK television sector.
This thesis discusses how the restructuring of the UK television industry in the 1980s and 1990s has affected learning and skills development in the sector. It is based on 71 semi-structured interviews with television freelancers and key informants in the industry, and a case study of a small regional independent company developed through semi-structured interviews and three months of participant observation.
To investigate the current learning and skills development mechanisms, this thesis engages with community-based learning theories. These are discussed in relation to industry characteristics such as commissioning and independent production and labour market realities related to freelance work and educational provision.
The findings reveal that the traditional on the job learning mechanisms within communities of practice are challenged under the new structural context characterised by unrestricted entry and progression and short-term projects within an uncertain employment context. Commercial pressures affect both the access to learning opportunities and the learning experience, mainly because of the lack of legitimate and gradual experiential learning possibilities, short-term involvement in the industry under pressures to perform. The thesis also discusses the realities of the work in a small regional independent production company as well as its benefits and limitations as a venue for community-based learning.
This thesis concludes with several policy recommendations which address some of the main challenges to the sustainable skills development in UK television. These recommendations subscribe to the need for introducing legitimate traineeships, entry rules and detaching learning from the commercial pressures in the sector
Biochemical and Biophysical Studies of Heme Binding Proteins from the Corynebacterium diphtheriae and Streptococcus pyogenes Heme Uptake Pathways
The Gram-positive pathogens Corynebacterium diphtheriae and Streptococcus pyogenes both require iron for survival. These bacteria have developed sophisticated heme uptake and transport protein machinery responsible for the import of iron into the cell, in the form of heme from the human host. The heme utilization pathway (hmu) of C. diphtheriae utilizes multiple proteins to bind and transport heme into the cell. One of these proteins, HmuT, delivers heme to the ABC transporter HmuUV. The axial ligation of the heme in HmuT was probed by examination of wild-type HmuT and a series of conserved heme pocket residue mutants, H136A, Y235A, R237A, Y272A, M292A, Y349A, and Y349F. Characterization by UV-visible absorption, resonance Raman, and magnetic circular dichroism spectroscopies indicated that H136 and Y235 are the axial ligands in HmuT. Electrospray ionization mass spectrometry was also utilized to assess the roles of conserved residues in contribution to heme binding.
The S. pyogenes streptococcal iron acquisition (sia)/heme transport system (hts) utilizes multiple proteins to bring host heme to the intracellular space. Both the substrate binding protein SiaA and the hemoprotein surface receptor Shr were investigated. The kinetic effects on SiaA heme release were probed through chemical unfolding of axial ligand mutants M79A and H229A, as well mutants thought to contribute to heme binding, K61A and C58A, and a control mutant, C47A. The unfolding pathways showed two processes for protein denaturation. This is consistent with heme loss from protein forms differing by the orientation of the heme in the binding pocket. The ease of protein unfolding is related to the strength of interaction of the residues with the heme.
Shr contains two NEAT (near-iron transporter) domains (Shr-N1 and Shr-N2) which can both bind heme. Biophysical studies of both Shr-N1 and Shr-N2 indicated a new class of NEAT domains which utilize methionine as an axial ligand, rather than a tyrosine. Thermal and chemical unfolding showed ferrous Shr-N1 and Shr-N2 to be most resistant to denaturation. Shr-N2 was prone to autoreduction. Together, sequence alignment, homology modeling, and spectral signatures are all consistent with two methionines as the heme ligands of this novel type of NEAT heme-binding domain
Public attitudes towards health after COVID-19 pandemic according to healthcare professionals
Introduction: The consequences of the Covid-19 pandemic in all aspects of life have affected not only the public attitudes towards health authorities and bodies, but also towards health as a basic human value.Purpose: To determine public attitudes 2 years after the start of the COVID-19 pandemic according to practicing healthcare professionals.Materials and Methods: An anonymous online survey using Google Forms was conducted in April 2022 among healthcare professionals who were students in “Management of health care” program.Results and discussion: According to health care professionals, there is low public trust between clients and health care providers. More than 1/5 of the respondents disagreed with the statement that "Our society has realized that health is the most important value", and 10.9% hesitated and answered "neither agree nor disagree". This attitude of the pledge to health as a value after 2 (two) years in conditions of a severe pandemic, may prove to be a great obstacle in the imposition of future measures by the health authorities related to the protection of public health.Conclusion: Actions are needed on the part of the health authorities in the country to build public trust in them. Adherence to measures imposed by health authorities are key in the event of a pandemic
PHP and Wireless Web Development
In this paper we consider how teaching traditional web development with PHP can be extended to wireless web development. Wireless technology is a new exciting development in the computing field and, as such, should be addressed in the computing curriculum. This paper suggests a way of introducing topics on wireless web devel-opment using wireless technologies and the server side programming language PHP; it gives an overview of the main wireless standards and presents examples using these technologies in conjunction with PHP. The exam-ples are aimed to be used in the “Internet Technologies” module for Foundation Degree students in Computing at London Metropolitan University
XML in the computing Curriculum
XML in the Computing Curriculum: XML (Extensible Markup Language) provides a way of structuring and describing data in a simple text format understandable for human beings and in the same way easily interpretable by computer programs. It is widely used in industry and it forms a fundamental standard for a number of emerging technologies, including Web Services, RDF (Resource Description Framework), RSS (Really Simple Syndication), as well as derivatives languages such as WML (Wireless Markup Language) and XHTML (Extensible HTML). This paper describes the experience of teaching XML at our department and the approach of embedding XML topics in already existing courses. It also points out the underpinning theoretical concepts related to XM
Use of Mobile Phone Technologies in the Classroom Context
This study investigates the use of mobile phone technologies in classroom interaction. Classroom interaction promotes active learning and enhances the student experience. We make on overview of current classroom mobile interactive technologies, discuss experiments with three different systems and evaluate these experiments
Asynchronous JavaScript Technology and XML (AJAX)
AJAX is a web development technique for building responsive web applications. The paper gives an overview
of the AJAX technique and explores ideas for teaching this technique in modules related to Internet
technologies and web development. Appropriate examples for use in lab sessions are also suggested
Malignant lymphoma during childhood and adolescence.Implications for oral health in longterm survivors
Malignant lymphomas are among the most common types of cancer in children and adolecents. Recent advances in the treatment of these malignancies in children have resulted in more lomg term survivors (LTSs) of these types of cancer. This has also resulted in many LTSs experinecing late adverse effects due to the disease and/or its treatment that was perviously unknown, among others; adverse influencing oral health.
The LTSs can expect to live long, and some of the adverse effects in the oral cavity can pose a significant to the survivors and oral health professionals in the future. More research is needed to determine the incidence and prevalence of adverse effects in the oral cavity in cancer and cancer treatment and the possible economic impact they can pose for the LTSs and the government
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