University Lecturers’ Level of Awareness and Proficiency of Internet Services and Resources for Academic Activities in Adamawa State, Nigeria

Abstract Internet services and resources are useful tools that facilitate effective and efficient conduct of academic activities such as teaching, learning, research, publishing, collaboration and communication. This paper determined the level of university lecturers’ awareness and proficiency of Internet services and resources for academic activities in Adamawa State, Nigeria. The study was guided by two objectives and two research questions. Survey research method was adopted. Stratified random sampling technique was used in selecting sample, while, Krejcie and Morgan (2006) was used to obtain sample size of 265 lecturers from Adamawa State University Mubi, American University of Nigeria Yola and Modibbo Adama University of Technology Yola. Self-designed questionnaire was used as the research instrument and data collected were analysed using descriptive statistics of frequency counts and percentages to answer the research questions using Statistical Package for Social Sciences (SPSS) tool, version 20.0. Findings of the study revealed that the level of university lecturers’ awareness of Internet services and resources for university lecturers’ academic activities in Adamawa State was moderate. The study has also established that the level of university lecturers’ proficiency of Internet services and resources for academic activities was moderate. The study recommended provision of Internet services and resources in the university libraries, sensitizing the lecturers on the importance of using the available Internet services and resources for their academic activities and providing instruction on information literacy programmes by the university libraries

Influence of Cracks on the Carbonation Resistance of Concrete Structures

Carbonation-induced corrosion of steel rebar embedded in concrete is one of the major issues influencing durability of reinforced concrete structures. It has been acknowledged that structural cracks in concrete influences the carbon dioxide (CO2) diffusivity and accelerates the carbonation-induced reinforcement corrosion, however most of the previous studies on the carbonation induced corrosion have concentrated on the un-cracked / unloaded concrete. This study investigates the impact of cracks caused by loading on the depth of carbonation into concrete. Concrete prisms (100x100x500 mm) were subjected to four different crack widths (0, 0.05-0.15 mm, 0.15-0.25 mm and 0.25-0.35 mm) and the carbonation depth was determined using an accelerated environment test programme based on the CEN/TS 12390-10:2007 and XRD analysis. The impact of replacing OPC cement by pulverized fuel ash (PFA) and ground granulated blast furnace slag (GGBS) on the carbonation depth in cracked concrete was also investigated. The results show a considerable influence of crack width on the depth of carbonation and the X-ray powder diffraction analysis (XRD) confirms these results. The penetration of carbon dioxide and accumulation of carbonation compound (CaCO3) were found to be concentrated at crack locations, whereas the carbonation depths at other locations were found to be less than the carbonation depth in un-cracked concrete. The results also demonstrate a significant increase in the penetration of carbonation due to the addition of supplementary materials in the samples when compared to the reference mixes

Hepatic artery aneurysm repair: a case report

<p>Abstract</p> <p>Introduction</p> <p>Hepatic artery aneurysms remain a clinically significant entity. Their incidence continues to rise slowly and mortality from spontaneous rupture is high. Repair is recommended in those aneurysms greater than 2 cm in diameter. It is not surprising that vascular comorbidities, such as ischaemic heart disease, are common in surgical patients, particularly those with arterial aneurysms such as these. The decision of when to operate on patients who require urgent surgery despite having recently suffered an acute coronary syndrome remains somewhat of a grey and controversial area. We discuss the role of delayed surgery and postoperative followup of this vascular problem.</p> <p>Case presentation</p> <p>A 58-year-old man was admitted with a 5.5 cm hepatic artery aneurysm. The aneurysm was asymptomatic and was an incidental finding as a result of an abdominal computed tomography scan to investigate an episode of haemoptysis (Figure <figr fid="F1">1</figr>). Three weeks prior to admission, the patient had suffered a large inferior myocardial infarction and was treated by thrombolysis and primary coronary angioplasty. Angiographic assessment revealed a large aneurysm of the common hepatic artery involving the origins of the hepatic, gastroduodenal, left and right gastric arteries and the splenic artery (Figures <figr fid="F2">2</figr> and <figr fid="F3">3</figr>). Endovascular treatment was not considered feasible and immediate surgery was too high-risk in the early post-infarction period. Therefore, surgery was delayed for 3 months when aneurysm repair with reconstruction of the hepatic artery was successfully performed. Graft patency was confirmed with the aid of an abdominal arterial duplex. Plasma levels of conventional liver function enzymes and of alpha-glutathione-<it>S</it>-transferase were within normal limits. This was used to assess the extent of any hepatocellular damage perioperatively. The patient made a good recovery and was well at his routine outpatient check-ups.</p> <p>Conclusion</p> <p>There is no significant difference in cardiac risk in patients who have undergone vascular surgery within 6 months of a myocardial infarction compared with those who have had the operation in the 6 to12 month time frame. Use of alpha-glutathione-<it>S</it>-transferase gives an indication of the immediate state of hepatic function and should be used in addition to traditional liver function tests to monitor hepatic function postoperatively.</p

Delayed-onset heparin-induced thrombocytopenia presenting with multiple arteriovenous thromboses: case report

<p>Abstract</p> <p>Background</p> <p>Delayed-onset heparin-induced thrombocytopenia with thrombosis, albeit rare, is a severe side effect of heparin exposure. It can occur within one month after coronary artery bypass grafting (CABG) with manifestation of different thrombotic events.</p> <p>Case presentation</p> <p>A 59-year-old man presented with weakness, malaise, bilateral lower limb pitting edema and a suspected diagnosis of deep vein thrombosis 18 days after CABG. Heparin infusion was administered as an anticoagulant. Clinical and paraclinical work-up revealed multiple thrombotic events (stroke, renal failure, deep vein thrombosis, large clots in heart chambers) and 48 ×10³/μl platelet count, whereupon heparin-induced thrombocytopenia was suspected. Heparin was discontinued immediately and an alternative anticoagulant agent was administered, as a result of which platelet count recovered. Heparin-induced thrombocytopenia, which causes thrombosis, is a serious side effect of heparin therapy. It is worthy of note that no case of delayed-onset heparin-induced thrombocytopenia with thrombosis associated with cardiopulmonary bypass surgery has thus far been reported in Iran.</p> <p>Conclusion</p> <p>Delayed-onset heparin-induced thrombocytopenia should be suspected in any patient presenting with arterial or venous thromboembolic disorders after recent heparin therapy, even though the heparin exposure dates back to more than a week prior to presentation; and it should be ruled-out before the initiation of heparin therapy.</p

Impacts of the Cairo Metro

The Cairo Metro the first in Africa and the Middle East is a two-line system, heavily-used. Data from the operator and a direct passenger survey are used to illustrate patterns of use and draw policy implications for other systems. While current revenue exceeds operating costs, cross-subsidies may exist between different passenger groups as a result of highly-discounted student season tickets. A fare increase in 1996 is used to estimate short-run elasticity of demand with respect to price, approximately 0.2, a similar figure to other metro systems. Substantial use is made of motorised feeder modes, notably shared taxis (paratransit minibuses). The high level of use occurs despite a substantial premium over other public transport fares, and lack of integrated ticketing. A likely explanation is that the fares are reasonable compared with incomes, and that the price differential is offset for many users by the time savings vis a vis congested traffic conditions.Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne

Multiple-length-scale elastic instability mimics parametric resonance of nonlinear oscillators

Spatially confined rigid membranes reorganize their morphology in response to the imposed constraints. A crumpled elastic sheet presents a complex pattern of random folds focusing the deformation energy while compressing a membrane resting on a soft foundation creates a regular pattern of sinusoidal wrinkles with a broad distribution of energy. Here, we study the energy distribution for highly confined membranes and show the emergence of a new morphological instability triggered by a period-doubling bifurcation. A periodic self-organized focalization of the deformation energy is observed provided an up-down symmetry breaking, induced by the intrinsic nonlinearity of the elasticity equations, occurs. The physical model, exhibiting an analogy with parametric resonance in nonlinear oscillator, is a new theoretical toolkit to understand the morphology of various confined systems, such as coated materials or living tissues, e.g., wrinkled skin, internal structure of lungs, internal elastica of an artery, brain convolutions or formation of fingerprints. Moreover, it opens the way to new kind of microfabrication design of multiperiodic or chaotic (aperiodic) surface topography via self-organization.Comment: Submitted for publicatio

National primary care responses to COVID-19: a rapid review of the literature

Objective The aim of this review, conducted in April 2020, is to examine available national primary care guidelines for COVID-19 and to explore the ways in which these guidelines support primary care facilities in responding to the demands of the COVID-19 pandemic. Design Rapid review and narrative synthesis. Data sources PubMed, Embase and Google, as well as the websites of relevant national health departments, were searched from 1 January 2020 to 24 April 2020. Eligibility criteria Documents included must be issued by a national health authority, must be specific to COVID-19 care, directed at healthcare workers or managers, and must refer to the role of primary care in the COVID-19 response. Results We identified 17 documents from 14 countries. An adapted framework on primary care challenges and responses to pandemic influenza framed our analysis. Guidelines generally reported on COVID-19 service delivery and mostly made specific recommendations for ensuring continued delivery of essential primary care services through telehealth or other virtual care modalities. Few offered guidance to support surveillance as a public health function. All offered guidance on implementing outbreak control measures, largely through flexible and coordinated organisational models with partners from various sectors. There was a lack of guidance to support supply chain management and practice resilience in primary care, and lack of personal protective equipment represents a serious threat to the provision of quality care during the pandemic. Conclusions Current national primary care guidelines for COVID-19 provide guidance on infection control and minimising the risk of spread in primary care practices, while supporting the use of new technology and coordinated partnerships. However, to ensure primary care practice resilience and quality of care are upheld, guidelines must offer recommendations on supply chain management and operational continuity, supported by adequate resources

Accuracy of Doppler-Echocardiographic Mean Pulmonary Artery Pressure for Diagnosis of Pulmonary Hypertension

Background: The validity of Doppler echocardiographic (DE) measurement of systolic pulmonary artery pressure (sPAP) has been questioned. Recent studies suggest that mean pulmonary artery pressure (mPAP) might reflect more accurately the invasive pressures. Methodology/Principal Findings: 241 patients were prospectively studied to evaluate the diagnostic accuracy of mPAP for the diagnosis of PH. Right heart catheterization (RHC) and DE were performed in 164 patients mainly for preoperative evaluation of heart valve dysfunction. The correlation between DE and RHC was better when mPAP (r = 0.93) and not sPAP (r = 0.81) was assessed. Bland-Altman analysis revealed a smaller variation of mPAP than sPAP. The following ROC analysis identified that a mPAP$25.5 mmHg is useful for the diagnosis of PH. This value was validated in an independent cohort of patients (n = 50) with the suspicion of chronic-thromboembolic pulmonary hypertension. The calculated diagnostic accuracy was 98%, based on excellent sensitivity of 98 % and specificity of 100%. The corresponding positive and negative predictive values were 100%, respectively 88%. Conclusion: mPAP has been found to be highly accurate for the initial diagnosis of PH. A cut-off value of 25.5 mmHg might be helpful to avoid unnecessary RHC and select patients in whom RHC might be beneficial

CTLA-4 Activation of Phosphatidylinositol 3-Kinase (PI 3-K) and Protein Kinase B (PKB/AKT) Sustains T-Cell Anergy without Cell Death

The balance of T-cell proliferation, anergy and apoptosis is central to immune function. In this regard, co-receptor CTLA-4 is needed for the induction of anergy and tolerance. One central question concerns the mechanism by which CTLA-4 can induce T-cell non-responsiveness without a concurrent induction of antigen induced cell death (AICD). In this study, we show that CTLA-4 activation of the phosphatidylinositol 3-kinase (PI 3-K) and protein kinase B (PKB/AKT) sustains T-cell anergy without cell death. CTLA-4 ligation induced PI 3K activation as evidenced by the phosphorylation of PKB/AKT that in turn inactivated GSK-3. The level of activation was similar to that observed with CD28. CTLA-4 induced PI 3K and AKT activation also led to phosphorylation of the pro-apoptotic factor BAD as well as the up-regulation of BcL-XL. In keeping with this, CD3/CTLA-4 co-ligation prevented apoptosis under the same conditions where T-cell non-responsiveness was induced. This effect was PI 3K and PKB/AKT dependent since inhibition of these enzymes under conditions of anti-CD3/CTLA-4 co-ligation resulted in cell death. Our findings therefore define a mechanism by which CTLA-4 can induce anergy (and possibly peripheral tolerance) by preventing the induction of cell death

A comparison of echocardiography to invasive measurement in the evaluation of pulmonary arterial hypertension in a rat model

Pulmonary arterial hypertension (PAH) is a life-threatening condition characterized by progressive elevation in pulmonary artery pressure (PAP) and total pulmonary vascular resistance (TPVR). Recent advances in imaging techniques have allowed the development of new echocardiographic parameters to evaluate disease progression. However, there are no reports comparing the diagnostic performance of these non-invasive parameters to each other and to invasive measurements. Therefore, we investigated the diagnostic yield of echocardiographically derived TPVR and Doppler parameters of PAP in screening and measuring the severity of PAH in a rat model. Serial echocardiographic and invasive measurements were performed at baseline, 21 and 35 days after monocrotaline-induction of PAH. The most challenging echocardiographic derived TPVR measurement had good correlation with the invasive measurement (r = 0.92, P < 0.001) but also more simple and novel parameters of TPVR were found to be useful although the non-invasive TPVR measurement was feasible in only 29% of the studies due to lack of sufficient tricuspid valve regurgitation. However, echocardiographic measures of PAP, pulmonary artery flow acceleration time (PAAT) and deceleration (PAD), were measurable in all animals, and correlated with invasive PAP (r = −0.74 and r = 0.75, P < 0.001 for both). Right ventricular thickness and area correlated with invasive PAP (r = 0.59 and r = 0.64, P < 0.001 for both). Observer variability of the invasive and non-invasive parameters was low except in tissue-Doppler derived isovolumetric relaxation time. These non-invasive parameters may be used to replace invasive measurements in detecting successful disease induction and to complement invasive data in the evaluation of PAH severity in a rat model