794 research outputs found
Identifying an Analytical Framework to Assess the Determinants of ICT Adoption in Libraries and its Implications for Teaching and Learning during Insecurity
The security situation in Nigeria, particularly in the country\u27s North-West and North-Central Zones, has forced the closure of many educational institutions. Teaching and learning have become more erratic as a result of this. This issue has far-reaching repercussions for librarians and information specialists. Libraries have long been regarded and recognized by educational institutions for their contribution to high-quality teaching and learning. Several studies have found that information and communication technology (ICT) can improve teaching and learning by facilitating access to information. As a result, governments and school administrators have been working to promote the use of ICT in libraries to aid teaching and learning. Despite these efforts, ICT adoption is still very low in most primary and secondary schools in Nigeria. This research conducted a conceptual analysis based on a literature search to identify the major criteria that should be considered when promoting the adoption of ICT in libraries to enhance quality teaching and learning in the face of security problem
Interpretation and Physical Modeling of Electronic Transport and Defect States in IGZO Thin-Film Transistors
This work is a comprehensive study on the interpretation and modeling of electronic transport behavior and defect states in indium-gallium-zinc-oxide (IGZO) TFTs. Key studies have focused on advancing the state of IGZO TFTs by addressing several challenges in device stability, scaling, and device modeling. These studies have provided new insight on the associated mechanisms and have resulted in the realization of scaled thin-film transistors that exhibit excellent electrical performance and stability. This work has demonstrated the ability to scale the conventional inverted staggered IGZO TFT down to one micron channel length, with excellent on-state and off-state performance where the VT â1 V, ”eff =12 cm2/Vs, Ileak †10-12 A/”m and SS â 160 mV/dec. The working source/drain electrodes are direct metal contact regions to the IGZO, which requires several microns of gate overlap to provide ohmic behavior with minimal series resistance and ensure tolerance to overlay error. New results utilizing ion implantation for self-aligned source/drain regions present a path towards submicron channel length. This strategy offers a reduction in channel length as well as parasitic capacitance, which translates to improvement in RC delay and associated voltage losses due to charge-sharing. The realization of self-aligned TFTs using boron ion implantation for selective activation was introduced in a first-time report of boron-doped IGZO. Cryogenic measurements made on long-channel devices has revealed temperature-dependent behavior that is not explained by existing TCAD models employed for defect states and carrier mobility. A completely new device model using Silvaco Atlas has been established which properly accounts for the role of donor-like oxygen vacancy defects, acceptor-like band-tail states, acceptor-like interface traps, and a temperature-dependent intrinsic channel mobility. The developed model demonstrates a remarkable match to transfer characteristics measured at T = 150 K to room temperature. A power-law fit for the ”ch = f(T) relationship, which resembles ăÎŒ ~ Tă^((+3)â2) behavior consistent with ionized defect scattering. The mobility model is expressly independent of carrier concentration, without dependence on the applied gate bias. The device model is consistent with a compact model developed for circuit simulation (SPICE) that has been recently refined to include on-state and off-state operation. While IGZO is the only AOS technology mature enough for commercialization, the effective electron channel mobility ”eff ~ 10 cm2/Vs presents a performance limitation. Other candidate AOS materials which have higher reported channel mobility values have also been investigated; specifically, indium-tungsten-oxide (IWO) and indium-gallium-tin-oxide (ITGO). These investigations serve as preliminary studies; device characteristics support the claims of high channel mobility; however the influence of defect states clearly indicates the need for further process development. The advancements realized in IGZO TFTs in this work will serve as a foundation for these alternative AOS materials
The Role of Academic Libraries in Restoring Quality Teaching and Learning in Education for Sustainable Development in Nigeria
The quality of teaching and learning is the key to sustainable development. This has inspired innumerable educational stakeholders to search for means of restoring quality teaching and learning in Nigeriaâs education system. To accomplish this, significant epistemological efforts have been made over the years on teaching methods/models, student learning styles, and curriculum content reforms. However, the role of academic libraries has not been given any significant consideration. It is, therefore, the conviction of this paper that sustainable development depends profoundly on the availability of information provided and accessed through a well-managed library for effective teaching, learning, and research. So, using desktop literature review and the author\u27s experience, this paper examines the roles of academic libraries in restoring quality teaching and learning for sustainable development in Nigerian institutions of higher learning. The study recommends and concludes that there may be scope for the augmentation of social media and ICT information literacy in academic library service delivery, which may address a plethora of challenges faced by the government in restoring quality teaching and learning for sustainable development
Novel diagnostic methods for rapid characterization of extended-spectrum beta-lactamase- and carbapenemase-producing Enterobacteriaceae
Klebsiella pneumoniae and Escherichia coli are two of the most clinically important pathogens of the family Enterobacteriaceae. Both can cause severe infections includ-ing urinary tract infections (UTI), bloodstream infections (BSI) and pneumonia. Both are also involved in dissemination of antibiotic resistance. The prevalence of extended-spectrum ÎČ-lactamase- (ESBL) producing Enterobacteriaceae (EPE) and carbapenemase-producing Enterobacteriaceae (CPE) are increasing worldwide. This is a severe threat to public health, as antibiotic treatment becomes limited. The general aim of the thesis was to investigate the clonal diversity and prevalence of ESBL in invasive isolates of Klebsiella pneumoniae from the Stockholm area, the acquisition of EPE/CPE in healthy Swedish tourists travelling to regions with high prevalence of EPE/CPE, and finally to evaluate rapid detection and characteriza-tion methods for EPE and CPE.
In Paper I, we studied the clonal structure of K. pneumoniae from BSI patients in a well-defined geographical area, as well as the prevalence of ESBL in these strains. We also characterized the clinical isolates to investigate the association between phylogroups, bacterial virulence factors, 30-day mortality and comorbidity. A total of 139 samples were collected from the Department of clinical microbiology at Karolinska University Hospital, Stockholm, Sweden. Only five out of 139 isolates were detected as multidrug-resistant (MDR) and all five isolates were EPE. Only one isolate was detected as a CPE. Further, all isolates were tested for mucoid pheno types, serotypes (K1, K2, K5, K20, K54 and K57) and screened for virulence genes using real-time PCR. To identify risk factors, we retrieved data from medical records including age, sex, time to adequate treatment, hospital acquired infections, comorbidity and mortality. The 30-day mortality was primary end-point. All isolates were further subjected to multilocus sequence typing (MLST) for phylogenetic analysis. We found that all isolates were divided into three distinct phylogroups; KpI (consisting of 96 isolates of K. pneumoniae) followed by phylogroup KpIII (consist-ing of 34 isolates of K. variicola) and phylogroup KpII (consisting of 9 isolates of K. quasipneumoniae). We observed 24/139 (17.3%) overall 30-day mortality. We also observed that K. variicola KpIII (29.4%) were highly associated with 30-day mortality compared to K. pneumoniae KpI isolates (13.5%). We also observed that several comorbidities; malignancy, diabetes mellitus, cirrhosis, biliary tract disor-ders and alcoholism among patients may influence the mortality.
In Paper II, we evaluated a commercial version of RAPIDECÂź CARBA NP for rapid detection of carbapenemases against 276 Gram-negative bacilli. According to the manufacturerâs protocol RAPIDECÂź CARBA NP assay was performed on 138 carbapenemase-producers and 138 non-carbapenemase-producers. Carbapenemase detection was also performed by using conventional and real-time PCR. A total of 135 out of 138 carbapenemase-producers were detected successfully by the RAPIDECÂź CARBA NP assay. The RAPIDECÂź CARBA NP assay was unable to detect one OXA-48-producing K. pneumoniae and two Acinetobacter baumannii producing OXA-23 and OXA-24 carbapenemases. The RAPIDECÂź CARBA NP assay successfully detected 135 non-carbapenemase producers. A total of two false positives; one Pseudomonas aeruginosa with OprD loss and efflux, one Enterobacter cloacae with impermeability were detected by the RAPIDECÂź CARBA NP assay. The overall sensitivity and specificity of the RAPIDECÂź CARBA NP assay was 97.8% and 98.5%, respectively.
In Paper III, we investigated the acquisition of EPE and CPE among healthy Swedish travellers visiting regions with high prevalence of EPE and CPE; Southeast Asia, Indian subcontinent, North Africa and the Middle East. We studied 188 healthy adult travellers and excluded 13 pre-travel colonized tourists from the analysis. Molecular characterization was performed using real-time PCR and survey data were collected for analysis. We detected a total of 67/175 tourist were colonized by EPE strains and most dominant species was E. coli (n=65), followed by K. pneumoniae (n=1) and Citrobacter freundii (n=1). CTX-M type (CTX-M-1 n=49, CTX-M-9 n=12) was the most prevalent EPE type detected in 61 isolates but carbapenemases were absent. Only six travellers had strains with the virulence factor pyelonephritis-associated pili-encoding genes (pap) genes, and all of those had travelled to India. One traveller to Thailand was colonized with colistin resistance gene mcr-1. The highest coloni-zation rate was detected among the travellers to the Indian subcontinent (49%) and northern Africa (44%) whereas lower rates were detected in travellers to Southeast Asia (19%) and Turkey (10%). EPE colonization was associated with diarrhea and antibiotic treatment during the trip but was not associated with sex, age, duration of trip, intake of proton-pump inhibitors, or use of oral cholera vaccine.
In paper IV, we assessed a CRISPR/Cas assisted optical DNA mapping method for rapid identification and characterization of plasmids during an EPE outbreak. We studied a total of 17 neonates initially colonized with ESBL-producing K. pneumoniae (ESBL-KP). In follow-up samples we observed that some of them were colonized with ESBL-producing E. coli. This method successfully detected two plasmids of different sizes; small size (80 kbp) and larger plasmid (162-222 kbp) in all ESBL-KP isolates. Using this method, we also observed that the blaCTX-M-15 gene was located on the smaller size plasmid. In follow-up samples we also observed that the ESBL-KP clone was present and blaCTX-M-15 was stable up to two years. This method demon-strated that plasmids can change over time: three deletions were observed in three plasmids of three isolates with different sizes (~ 5 kbp), (~ 55 kbp) and (~ 31 kbp) and an inversion of 31 kbp in another isolate. This method also confirmed that resistance plasmids were not transferred from one patient to another.
In conclusion, this thesis provides new knowledge on the prevalence of EPE and CPE among BSI patients and healthy Swedish tourists, along with describing the molecular features of ESBL- and carbapenemase-producing Enterobacteriaceae. This thesis also demonstrates the performance of a rapid phenotypic carbapenemase detection assay, as well as a novel CRISPR/Cas-assisted optical DNA mapping method for rapid plasmid characterization
A Proposed e-Readiness Assessment Model for University Libraries in Nigeria
Information and communication technology (ICT) deployment has been prompted by the desire to increase effective services and have a favorable impact on organizational development. The development in the creation of e-readiness frameworks in many organizations, including libraries, is as a result of this demand. While the e-readiness study is widely used in libraries developed nations, it has not yet expanded into many libraries in underdeveloped nations. This studyâs objective is to close this knowledge gap by outlining a model for e-readiness in Nigeria, with a focus on university libraries. The study has an e-readiness framework with eight (8) variables that is guided by the Network Readiness Framework, the Digital Media Readiness, the Digital Opportunity index, and the e-Readiness Ranking. The suggested model will use the eight variables, internet literacy, human resources, ICT policy, affordability, access, education, and usage, as measures and measurements. The proposed approach is intended to provide as a springboard for empirical investigation into the evaluation of e-readiness in Nigerian University libraries
Continuance intention to use electronic collection system in Nigerian federal hospitals
Computerized information systems are being used by public sector organizations in the world over. However, studies have shown that there is under-utilization of such systems in the developing countries. Even though there are considerable numbers of studies that were conducted in finding out the influencing factors that lead to voluntary use of technology for personal use, still there are limited empirical studies that investigate the factors that influence continuance use intention of electronic information systems in mandatory system use environments in Nigeria. Thus, the purpose of this study is to empirically investigate the influence of perceived usefulness, perceived ease of use, perceived information quality and perceived enjoyment on the continuance use intention of electronic collection system in Nigerian federal hospitals. It also examines the moderating effect of computer selfefficacy on the relationship between perceived usefulness and continuance intention; and perceived ease of use and
continuance intention. The study employs a crosssectional survey and uses cluster sampling technique to collect data from 354 electronic collection system users with the help of self-administered questionnaire. Out of the 354 questionnaires distributed, 274 were returned, but only 231 responses representing 65% response rate were valid for analysis. The findings of the study revealed that perceived usefulness, perceived ease of use and perceived information quality positively and significantly influence continuance intention, whereas perceived enjoyment does not. In addition, the result shows that computer selfefficacy does not moderate the relationship between perceived usefulness and continuance intention; and perceived ease of use and continuance intention. Though the study had contributed in extending the Technology Acceptance Model to explain the behavior of public sector employees toward electronic system use in the workplace, it is only applicable to federal government hospitals alone. Therefore, further studies could be conducted to include other hospitals at both state and local government levels in Nigeria
ASSESSMENT OF JOB SATISFACTION OF EMPLOYEESâ IN AHMADU BELLO UNIVERSITY LIBRARY ZARIA
The study examined the assessment of job satisfaction of employeesâ in Ahmadu Bello University Library Zaria. Survey research design was adopted for the study. Total population was 359 librarians in made up of professionals and para-professionals. Total enumeration was used for the study. The instrument for data collection was a validated questionnaire. Cronbachâs alpha results ranged from 0.86 to 0.90. The response rate was 87.5%. Data were analyzed using Pearson product Moment Correlation and Multiple Regression. The findings revealed that librariansâ level of Normative commitment is high; while their Affective and Continuance employeesâ commitment in Ahmadu Bello University Library Zaria, Nigeria is low. The study concluded that librariansâ level of assessment was determined by the extent of employeesâ commitment. The study recommended that for management of Ahmadu Bello University Library Zaria to succeed, they must find means of promoting job satisfaction among their employees
Kinetics and thermodynamics studies on Alizarin red adsorption onto adsorbent derived from orange peels
No Abstract
Identifying Recent Behavioral Data Length in Mobile Phone Log
Mobile phone log data (e.g., phone call log) is not static as it is
progressively added to day-by-day according to individ- ual's diverse behaviors
with mobile phones. Since human behavior changes over time, the most recent
pattern is more interesting and significant than older ones for predicting in-
dividual's behavior. The goal of this poster paper is to iden- tify the recent
behavioral data length dynamically from the entire phone log for recency-based
behavior modeling. To the best of our knowledge, this is the first dynamic
recent log-based study that takes into account individual's recent behavioral
patterns for modeling their phone call behaviors.Comment: 14th EAI International Conference on Mobile and Ubiquitous Systems:
Computing, Networking and Services (MobiQuitous 2017), Melbourne, Australi
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