Effect of Carbon Nanofiber on Mechanical Behavior of Asphalt Concrete

Uses of fibers to improve material properties have a scientific background in recent years in civil engineering. Use of Nanofiber reinforcement of materials refers to incorporating materials with desired properties within some other materials lacking those properties. Use of fibers for improvement is not a new phenomenon as the technique of fiber-reinforced bitumen began as early as 1950, but using nanofiber is a new idea. In this research the mechanical properties of asphalt mixture that have been modified with carbon nanofiber were investigated using mechanical tests, which can improve the performance of flexible pavements. To evaluate the effect of nanofiber contents on bituminous mixtures, laboratory investigations were carried out on the samples with and without nanofibers. During the course of this study, various tests were undertaken applying the Marshall test, indirect tensile test, resistance to fatigue cracking by using repeated load indirect tensile test and creep test. Carbon nanofiber exhibited consistency in results and it was observed that the addition of nanofiber can change the properties of bituminous mixtures, increase its stability and decrease the flow value. Results indicate that nanofiber have the potential to resist structural distress in the pavement and thus improve fatigue by increasing resistance to cracks or permanent deformation, when growing traffic loads. On the whole, the results show that the addition of carbon nanofiber will improve some of the mechanical properties such as fatigue and deformation in the flexible pavement

Case Study Evaluation of Steel Girder of Bridge Replacement by GFRP

Nowadays, because of the steel desired tensile, compressive strength, and light weight especially in the large spans, it has been widely popular in the bridge construction. On the other hand, there are some disadvantages including corrosion, buckling and weaknesses in the higher temperatures, and unsuitable weld which would be resolved using Fibres Reinforced Polymer (FRP) profiles. The FRP is a remarkable class of composite polymers that can improve structural elements behaviours like as resistance against corrosion, fire, electricity, and magnetic fields. In this paper, composite GFRP & UHF beams along with the behaviour of I-shaped beam were studied and discussed under the point loads using numerical models, results were compared and verified with the experimental tests whereas two different beams were modelled and verified under static progressive loading performed with ABAQUS as an FEM base software. Finally, Moddares-Haqqani that is a steel girder bridge has been modeled by SAP software and maximum displacement has been determined. Then 4 GFRP beams modeled by ABAQUS software and best section has been determined. Beams are under dead and live loading. Purposes of this paper are evaluating of use of GFRP materials as a basic material in construction process and compare this operation with steel. Results shown that because of lower modulus of elasticity in GFRP compare with steel, displacement has increase in GFRP beams and hence beams dimension must be increase to limit displacement.&nbsp

Treatment aspects, prognostic factors and outcome measures of lymphatic malformations

Lymphatic malformations (LMs) are structural defects in the lymphatic vessels. LMs are histologically benign lesions, however, due to localization, size and unexpected swelling, they may cause serious complications that threaten vital functions such as compression on the airways. A large swelling of the face or neck may also affect the esthetics and thus constitute a psychological strain for the patients and their families. LMs are also highly immunologically reactive and are prone to recurrent infections and inflammation causing pain as well as chronic oozing wounds. There are no available guidelines that describe management and follow up of LMs. Surgery has previously been considered the first treatment option. Surgery, however, has limitations as LMs often infiltrate adjacent structures, such as vessels and nerves making total resection difficult and potentially dangerous. Percutaneous sclerotherapy has replaced surgery as the primary treatment in most cases. Sclerotherapy also has limitations and can potentially cause serious complications such as unpredictable swelling that affects vital functions and cause scarring in the surrounding tissue. Review of the literature raises several questions. It is still unclear, which should be the treatment criteria for LMs and how to follow up the patients. LMs are rare conditions, however, our department has accumulated a large cohort of patients. No other institution has published a larger cohort of patients with LMs. The main objectives of this project was to evaluate the surgical- and interventional outcome of the treatment of LM patients, identify prognostic factors and better understand the inflammatory mechanisms of OK-432 treatment. In this dissertation the following research questions were addressed. 1. Are there immunological pre-requisites that can be analyzed in a blood sample that provide prognostic information on the outcome of sclerotherapy using OK-432? 2. How good is the long-term clinical outcome and the health-related quality of life of patients treated with sclerotherapy using OK-432? 3. Is it possible to establish a treatment algorithm for patients with LMs involving the mediastinum by evaluating the current management with both surgery and sclerotherapy? In Paper I the hypothesis was that Toll-like receptor (TLR) expression in monocytes after treatment with the TLR4-ligand lipopolysaccharide (LPS) could be used to predict successful OK-432 treatment. Blood was analyzed from children with low response (LR, n = 6) and high response (HR, n = 5) to previous OK-432 sclerotherapy. Monocytes were stimulated with LPS. TLR4 expression was analyzed with fluorescence-activated cell sorting (mean fluorescence intensity (MFI)). The mean TLR4 upregulation after LPS stimulation was 3.6 times higher in the HR group than in the LR group and non-stimulated controls (P = 0.037). Dynamic TLR4 expression most probably represents a predictive parameter for the treatment of LMs with OK-432. In Paper II, further analysis showed that the mean expression of TLR 4 after LPS stimulation was comparable in both groups (HR 1142 ± 652 units, LR 839 ± 427 units, P = 0.85). The pre-stimulation values in the LR group compared with the HR group were 950 ± 718 vs. 477 ± 341 with considerable differences of the mean expression changes after LPS stimulation (HR 665±683vs.LR 111±605,P=0.08). The difference in TLR4 upregulation on monocytes after LPS stimulation in the LR group compared with the HR group can be explained by TLR preconditioning. The findings suggest that absolute threshold values of TLR 4 could be a predictive parameter for the treatment of LMs with OK-432. In Paper III demographic data and long-term outcome in patients with LMs treated with OK-432 were analyzed. We enrolled 131 of 138 eligible patients treated with OK-432 for LMs between 1998 and 2013 in a retrospective study. The outcome was assessed with a clinical examination, evaluated with a clinical assessment score (CAS), and a questionnaire. LMs were localized to the head/neck (60%), the trunk (20%) and the extremities (6%) or involved more than one region (14%). Patients with microcystic (10%), macrocystic (21%) and mixed lymphatic malformations (69%) underwent a median number of three, two and two injection treatments, respectively. OK-432 treatment resulted in a successful outcome in 70% of patients with LMs. The long-term outcome was comparable to the short-term outcome. The number of injections, previous treatment and lesion localization predicted the clinical outcome. Four unsatisfactory attempts of sclerotherapy were shown to be a breakpoint for surgery. In Paper IV the management of patients with LMs involving the mediastinum was reviewed and a treatment algorithm was suggested. All patients with LMs involving the mediastinum between 2009-2015 at our institution were reviewed. We collected demographic data, data on investigations, management, and complications of the treatment, as well as outcomes at follow-up. Complications were described according to the Clavien- Dindo classification. The patients treated with sclerotherapy and the operated patients had comparable numbers of Clavien-Dindo grade I-II complications. Clavien-Dindo grade IIIIV complications were five times more frequent after sclerotherapy than after surgery. The clinical outcome was excellent for the operated patients and fair to good for the patients receiving only sclerotherapy. Patients with cervical LM involving the mediastinum represent a high-risk group with respect to the severity of complications following sclerotherapy. Surgical resection of the LM in the mediastinum is recommended, with the possibility of intra-operative sclerotherapy as an adjunctive. In Paper V the health-related quality of life (HRQOL) was assessed in the cohort of Swedish children and adolescents with LMs who underwent injection treatment with OK-432 at our institution between 1998 and 2013. A study-specific questionnaire was sent to all patients with at least five years’ follow up after the first injection treatment asking for persisting symptoms and satisfaction with the treatment and care. KIDSCREEN-52 was used to assess HRQOL. Patients with LMs localized in the head and neck area and repeated sclerotherapy constitute a risk for negatively affected HRQOL

A High Capacity Energy Efficient Approach for Traffic Transmission in Cellular Networks, Journal of Telecommunications and Information Technology, 2015, nr 3

The efficiency of cellular networks can be improved in various aspects such as energy consumption, network capacity and interference between neighboring cells. This paper proposes a high capacity energy efficient scheme (HCEE) for data transmission in cellular networks in a country area. In this paper, the authors obtain a new equation to characterize the minimal required output power for traffic transmission between a base station (BS) and a mobile user (MU) based on the MU distance from the BS. Also, the cells boundaries (the boundary of overlapping areas of neighboring cells) by two static and dynamic approaches are specified. This work helps for better frequency allocation to MUs and allows increasing network capacity. In this paper, the analytical modeling in order to formulate the HCEE algorithm and evaluate its performance is used. The performance evaluation results show the simplicity of the HCEE algorithm and its effect on energy consumption decline, network capacity enhancement and the interference reduction

LDAOR - Location and Direction Aware Opportunistic Routing in Vehicular Ad hoc Networks, Journal of Telecommunications and Information Technology, 2016, nr 1

Routing in Vehicular Ad hoc Networks (VANETs) has found significant attention because of its unique features such as lack of energy constraints and high-speed vehicles applications. Besides, since these networks are highly dynamic, design process of routing algorithms suitable for an urban environment is extremely challenging. Appropriate algorithms could be opportunistic routing (OR) where traffic transmission is performed using the store-carry-forward mechanism. An efficient OR mechanism, called Location and Direction Aware Opportunistic Routing (LDAOR), is proposed in this paper. It is based on the best neighbor node selection by using vehicles positions, vehicles directions, and prioritization of messages from buffers, based on contact histories and positions of neighbor nodes to destination. In LDAOR, when multiple nodes make contact with a carrier node, the closest neighbor node to destination is selected as the best forwarder. However, when only one node makes contact with the carrier node, the message is delivered to it if it moves toward the destination. Using the ONE simulator, the obtained performance evaluation results show that the LDAOR operates better than conventional OR algorithms. The LDAOR not only increases delivery rate, but also reduces network overhead, traffic loss, and number of aborted messages

Improvement of the Performance of Database Access Operations in Cellular Networks, Journal of Telecommunications and Information Technology, 2012, nr 3

Reducing the traffic volume of location updating is a critical issue for tracking mobile users in a cellular network. Besides, when user x wants to communicate with user y, the location of user y must be extracted from databases. Therefore, one or more databases must be accessed for updating, recording, deleting, and searching. Thus, the most important criterion of a location tracking algorithm is to provide a small database access time. In this paper, we propose a new location tracking scheme, called Virtual Overlap Region with Forwarding Pointer (VF), and compare the number of database accesses required for updating, deleting, and searching operations for the proposed scheme and other approaches proposed for cellular networks. Our VF scheme like Overlap Region scheme reduces the updating information when a user frequently moves in boundaries of LAs. Unlike Overlap Region, the VF can reduce number of database accesses for searching users’ information

The VASCERN-VASCA working group diagnostic and management pathways for severe and/or rare infantile hemangiomas

The European Reference Network on Rare Multisystemic Vascular Diseases (VASCERN), is dedicated to gathering the best expertise in Europe and provide accessible cross-border healthcare to patients with rare vascular dis-eases. Infantile Hemangiomas (IH) are benign vascular tumors of infancy that rapidly growth in the first weeks of life, followed by stabilization and spontaneous regression. In rare cases the extent, the localization or the number of lesions may cause severe complications that need specific and careful management. Severe IH may be life-threatening due to airway obstruction, liver or cardiac failure or may harbor a risk of functional impairment, severe pain, and/or significant and permanent disfigurement. Rare IHs include syndromic variants associated with extracutaneous abnormalities (PHACE and LUMBAR syndromes), and large segmental hemangiomas. There are publications that focus on evidence-based medicine on propranolol treatment for IH and consensus state -ments on the management of rare infantile hemangiomas mostly focused on PHACES syndrome. The Vascular Anomalies Working Group (VASCA-WG) decided to develop a diagnostic and management pathway for severe and rare IHs with a Nominal Group Technique (NGT), a well-established, structured, multistep, facilitated group meeting technique used to generate consensus statements. The pathway was drawn following two face-to-facePeer reviewe

The VASCERN-VASCA working group diagnostic and management pathways for lymphatic malformations

Lymphatic malformations (LMs) are developmental defects of lymphatic vessels. LMs are histologically benign lesions, however, due to localization, size, and unexpected swelling, they may cause serious complications that threaten vital functions such as compression of the airways. A large swelling of the face or neck may also be disfiguring and thus constitute a psychological strain for patients and their families. LMs are also highly immunologically reactive, and are prone to recurrent infections and inflammation causing pain as well as chronic oozing wounds.The European Reference Network on Rare Multisystemic Vascular Diseases (VASCERN) is dedicated to gathering the best expertise in Europe. There are only few available guidelines on management and follow up of LMs, which commonly focus on very specific situations, such as head and neck LM (Zhou et al., 2011). It is still unclear, what constitutes an indication for treatment of LMs and how to follow up the patients. The Vascular Anomalies Working Group (VASCA-WG) of VASCERN decided to develop a diagnostic and management pathway for the management of LMs with a Nominal Group Technique (NGT), a well-established, structured, multistep, facilitated group meeting technique used to generate consensus statements. The pathway was drawn following 2 face-to-face meetings and multiple web meetings to facilitate discussion, and by mail to avoid the influence of most authoritative members.The VASCA-WG has produced this opinion statement reflecting strategies developed by experts and patient representatives on how to approach patients with lymphatic malformations in a practical manner; we present an algorithmic view of the results of our work.Peer reviewe

The VASCERN-VASCA Working Group Diagnostic and Management Pathways for Venous Malformations.

UNLABELLED To elaborate expert consensus patient pathways to guide patients and physicians toward efficient diagnostics and management of patients with venous malformations. METHODS VASCERN-VASCA (https://vascern.eu/) is a European network of multidisciplinary centers for Vascular Anomalies. The Nominal Group Technique was used to establish the pathways. Two facilitators were identified: one to propose initial discussion points and draw the pathways, and another to chair the discussion. A dermatologist (AD) was chosen as first facilitator due to her specific clinical and research experience. The draft was subsequently discussed within VASCERN-VASCA monthly virtual meetings and annual face-to-face meetings. RESULTS The Pathway starts from the clinical suspicion of a venous type malformation (VM) and lists the clinical characteristics to look for to support this suspicion. Strategies for subsequent imaging and histopathology are suggested. These aim to inform on the diagnosis and to separate the patients into 4 subtypes: (1) sporadic single VMs or (2) multifocal, (3) familial, multifocal, and (4) combined and/or syndromic VMs. The management of each type is detailed in subsequent pages of the pathway, which are color coded to identify sections on (1) clinical evaluations, (2) investigations, (3) treatments, and (4) associated genes. Actions relevant to all types are marked in separate boxes, including when imaging is recommended. When definite diagnoses have been reached, the pathway also points toward disease-specific additional investigations and recommendations for follow up. Options for management are discussed for each subtype, including conservative and invasive treatments, as well as novel molecular therapies. CONCLUSION The collaborative efforts of VASCERN-VASCA, a network of the 9 Expert Centers, has led to a consensus Diagnostic and Management Pathways for VMs to assist clinicians and patients. It also emphasizes the role of multidisciplinary expert centers in the management of VM patients. This pathway will become available on the VASCERN website (http://vascern.eu/)