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Sepsis remains a major challenge in clinical practice with considerable morbidity and mortality despite modern treatments. Clinicians need good diagnostic and prognostic markers to identify infected patients who would rapidly benefit from prompt, empirical antibiotic therapy and other supportive treatment. to comparison of Presepsin (CD14), Procalcitonin (PCT) and C- reactive protein (CRP) at different SOFA and APACHE II scores in sepsis patients. A prospective cohort observational study was conducted in Critical Care Medicine Department, Faculty of medicine, Cairo University, Egypt recruiting admitted adult critically ill patients diagnosed. All subjects were recruited during the period from December 2013 to November 2015. All subjects were subjected to complete history taking, clinical examination, Complete blood count, Kidney and Liver function, Coagulation profiles, blood, urine, and sputum cultures ± wound or drain culture, presepsin, PCT and CRP plasma concentrations. Mean age of our study group was 49.8±16.05 years and mean APACHE II score 14±4.4 with mean length of ICU stay was 13.6±7.06 days.There was significantly higher frequency of DM and HTN in Non- survivors group than Survivors.SOFA score was significantly higher at all assessments in Non- survivors as compared to survivors on admission and at day 1, 3,7 and 15.

This paper provides a critical review on the current status of graphene-reinforced metal matrix composites (GRMMCs) in an effort to guide future work on this topic. Metal matrix composites are preferred over other types of composites for their ability to meet engineering and structural demands. Graphene is considered an ideal reinforcement material for composites due to its unique structure and extraordinary physical, thermal, and electrical properties. Incorporating graphene as a reinforcement in metals is a way of harnessing its extraordinary properties, resulting in an enhanced metallic behavior for a wide variety of applications. Combining graphene with bulk metal matrices is a recent endeavor that has proven to have merit. A systematic study is needed to critically examine the efforts applied in this field, the successes achieved, and the challenges faced. This review highlights the three main pillars of GRMMCs: synthesis, structure, and properties. First, it discusses the synthesis techniques utilized for the fabrication of GRMMCs. Then, it highlights the resulting microstructures of the composites, including graphene dispersion and interfacial interactions. Finally, it summarizes the enhancements in the mechanical, electrical, thermal, and tribological properties of GRMMCs, while highlighting the effects of graphene type and content on those enhancements. Other information Published in: Reviews on Advanced Materials Science License: http://creativecommons.org/licenses/by/4.0 See article on publisher's website: http://dx.doi.org/10.1515/rams-2020-0007

The rapid development of technology has brought about a revolution in healthcare stimulating a wide range of smart and autonomous applications in homes, clinics, surgeries and hospitals. Smart healthcare opens the opportunity for a qualitative advance in the relations between healthcare providers and end-users for the provision of healthcare such as enabling doctors to diagnose remotely while optimizing the accuracy of the diagnosis and maximizing the benefits of treatment by enabling close patient monitoring. This paper presents a comprehensive review of non-invasive vital data acquisition and the Internet of Things in healthcare informatics and thus reports the challenges in healthcare informatics and suggests future work that would lead to solutions to address the open challenges in IoT and non-invasive vital data acquisition. In particular, the conducted review has revealed that there has been a daunting challenge in the development of multi-frequency vital IoT systems, and addressing this issue will help enable the vital IoT node to be reachable by the broker in multiple area ranges. Furthermore, the utilization of multi-camera systems has proven its high potential to increase the accuracy of vital data acquisition, but the implementation of such systems has not been fully developed with unfilled gaps to be bridged. Moreover, the application of deep learning to the real-time analysis of vital data on the node/edge side will enable optimal, instant offline decision making. Finally, the synergistic integration of reliable power management and energy harvesting systems into non-invasive data acquisition has been omitted so far, and the successful implementation of such systems will lead to a smart, robust, sustainable and self-powered healthcare system.

Additional file 1: Appendix A. The following table illustrates the CCAs features, code, simulation results and ranking based on the studied measures. Appendix B: The following figure illustrates the specifications and classifications of the questionnaire takers (38 respondents).

The aim of integrity protection process is not only to secure the send message, but also ensures that the original message is not modified during sending the message. In this paper, a novel proposed model is proposed to verify that the sent message was not modified. The proposed model starting with encrypting the original message and applying one of the hash functions on the message. The ciphered message, private key, and the output of hash function was reshaped to apply Discrete Cosine Transform (DCT), Zig-zag ordering, and Huffman coding to obtain a compressed text, this compressed text is then hidden in an image. The same steps with a reverse order are applied on the receiver to obtain the decrypted message and then apply the same hash function to verify that the message was not changed. Different experiments were conducted and the results demonstrated that the proposed model achieved high integrity protection., 6 Pages, 3 Figures. arXiv admin note: text overlap with arXiv:1401.5561 by other authors

Increasing water consumption is a problem faced by the world; one of its solutions is reusing water. Reuse is about changing processes that result in polluted water byproducts so that the resulting water is usable again. Our solution is to reuse ballast water in transporting oil. Oil ships are heading from one country to another, and they are loaded with oil. These ships return to be loaded with ballast water instead of oil. The first step is to place a source of solid air in the tanks to provide some bubbles inside the tank. Secondly, put some of the iron peels inside the tanks to stick these peels with the bubbles, then by a magnetic field attracts the pollutant bubbles attached to the iron scales, and the ballast water remains in the tank to be used again. The results were astounding because they achieved the design requirements.

With the increasing widely spread digital media become using in most fields such as medical care, Oceanography, Exploration processing, security purpose, military fields and astronomy, evidence in criminals and more vital fields and then digital Images become have different appreciation values according to what is important of carried information by digital images. Due to the easy manipulation property of digital images (by proper computer software) makes us doubtful when are juries using digital images as forensic evidence in courts, especially, if the digital images are main evidence to demonstrate the relationship between suspects and the criminals. Obviously, here demonstrate importance of data Originality Protection methods to detect unauthorized process like modification or duplication and then enhancement protection of evidence to guarantee rights of incriminatory. In this paper, we shall introduce a novel digital forensic security framework for digital image authentication and originality identification techniques and related methodologies, algorithms and protocols that are applied on camera captured images. The approach depends on implanting secret code into RGB images that should indicate any unauthorized modification on the image under investigation. The secret code generation depends mainly on two main parameter types, namely the image characteristics and capturing device identifier. In this paper, the architecture framework will be analyzed, explained and discussed together with the associated protocols, algorithms and methodologies. Also, the secret code deduction and insertion techniques will be analyzed and discussed, in addition to the image benchmarking and quality testing techniques., Comment: 11 pages, 19 figures and one table

Colloque avec actes et comité de lecture. internationale.; International audience; In this paper, we analyse a Stackelberg game between a customer and multiple suppliers faced with the proposition of a new product manufacturing. Suppliers apply base stock policy to replenish their inventories. The customer, being the leader, anticipates suppliers’ optimal base stock levels and allocates demand volume to suppliers in a way to maximize his own profit. In addition, the customer as well as each of the suppliers has the option of accepting or rejecting this new product affair according to its profitability. We let suppliers cooperate by forming coalitions. In order to study coalition structures stability, we endow suppliers with foresight. We show that the grand coalition may be unstable particularly when system load is relatively low. We show that suppliers’ profits are better when they cooperate if the system load is high. However, for weakly loaded systems, suppliers may find it better not to cooperate. By comparing to the centralized system performances, we show that decentralization of decisions may lead to the loss of the affair in quite a lot of situations even when suppliers cooperate, and that in the case of acceptance, the system inefficiency is considerable.

International audience; This paper analyses the performances of a supplier who, besides his own products, has the possibility to accept or not the production of a personalized product for a customer who may be a new one. The contract with this customer specifies the demand arrival rate, the sale price and the backorder cost. Face to this proposition, the supplier has to decide whether to accept or not the contract and how to manage his production system: which products must be produced according to make-to-order policy? Which quantity of finished goods must be kept in the stock for those to produce under make-to-stock policy? We characterize analytically and through numerical examples the structure of the optimal decision with regard to the questions quoted above. We extend the analysis to the case where the supplier can choose between several new product proposals.

In this paper, the authors consider a single stage multi-product manufacturing facility producing a large number of end-products for delivery within a service constraint for the customer lead-time. The manufacturing facility is modeled as a multi-product, multi-priority queuing system. In order to reduce inventory costs, an e±cient priority allocation between items consists in producing some items according to a Make-To-Stock (MTS) policy and others according to a Make-To-Order (MTO)policy epending on their features (costs, required lead-time, demand rates). The authors propose a general optimization procedure that gives a near-optimal °ow control (MTO or MTS) to associate with each product and the corresponding near-optimal priority strategy. We illustrate e±ciency of our procedure via several examples and by a numerical analysis. In addition, we show numerically that a small number of priority classes is su±cient to obtain near-optimal performances.

International audience; RESUME : Dans la chaîne logistique, l'information avancée est disponible sous différentes formes : ordres à l'avance, prévisions, information partagée, engagements… L'utilisation correcte de cette information avancée aboutit à l'amélioration de performance de la chaîne logistique. Intuitivement, une meilleure information sur la demande future conduit à une baisse des niveaux de stock pour un même taux de service. Plusieurs travaux qui se sont intéressés à des modèles à capacité finie ont confirmé ce résultat. A travers de ces travaux, nous distinguons deux approches :-Le client n'accepte pas les livraisons antérieures à la date d'échéance.-Le client accepte les livraisons antérieures à la date d'échéance. Dans un contexte de production par anticipation, mono-étage, modélisé par des files d'attente de type M/M/1, nous montrons que ces deux approches sont des cas particuliers d'une approche plus générale d'information avancée avec fenêtre de temps et nous calculons analytiquement les performances de ce modèle. Nous enrichissons ce travail par des exemples numériques.

The most important thermoelectric materials for applications close to room temperature are made of bismuth telluride. The number of applications for these materials, however, is constrained by their extremely low heat conversion efficiencies. Single Walled Carbon Nanotubes (SWCNTs) are employed as a nanofiller in this work to create a p-type bismuth telluride nanocomposite with the composition Bi0.4Sb1.6Te3. Ball milling was used to prepare the samples with various SWCNTs concentrations for a total milling time of 16 hours. According to the findings, the addition of SWCNTs enhanced the thermoelectric characteristics of p-type bismuth telluride. The addition of SWCNTs raised ZT at room temperature by 5% (from 0.86 to 0.90) for the optimal sample (0.05 wt.% SWCNTs),. At 150 °C, ZT improved by 4 %, achieving a value of 1.26 for the same sample (0.05 wt.% SWCNTs). Consequently, demonstrating that SWCNTs may improve the thermoelectric characteristics of the p-type bismuth telluride samples.

The debate between growing economies and increased environmental burdens forces countries to make excessive efforts to reduce their energy consumption. The reduction of weight in structural materials, such as Al-based and Ni-based alloys that are utilized in everyday aspects, has a great potential for reducing the consumption of energy and minimizing the burden on the environment. High entropy alloys (HEAs) are a new class of multi-component alloy systems in which the design of the alloys is based not on adding solutes to a single "base" element, but rather on choosing elements that will form solid solutions when mixed with specific concentrations. In this work, we studied the effect of aluminum content on novel NiCrCoNb HEAs and produced low-cost and low-density HEAs with superior unprecedented mechanical properties through simple thermomechanical treatments.

A fundamental understanding of the mechanisms of phase stability of high entropy alloys (HEAs) and the influence of refractory elements is a recent topic of active research. This study investigates the effect of Niobium (Nb), as a refractory element, on the phase stability and mechanical properties of NiCoCrAlNb HEAs. In this thesis, Ni0.55CoCrAlNbx (x= 0, 0.01, 0.03, 0.05) high entropy alloys are prepared by using a vacuum arc melting technique. X-ray diffraction results demonstrate a single solid solution phase FCC in all samples. The addition of Nb content is studied through thermomechanical assessments and microstructure processing. Remarkable tensile properties were achieved for the HEA with 5% Nb content. The thermomechanical treatments were optimized, and the best combination of mechanical properties was obtained at an aging temperature of 950°C for one hour. Significant improvements are detected in tensile properties as the Nb content is increased. The yield and ultimate strength values of the optimized sample were found to be 1050 MPa and 1534 MPa, respectively. All the specimens aged at 950°C had a good tensile ductility of 34%. This thesis indicates that the properties of HEAs could be well tailored using thermomechanical and microstructure management for a high-performance HEA in industrial engineering applications.

Modern new technologies, including carbon nanomaterials, polymers performed electronically, and their nanocomposites enhance the performance of thermoelectric materials. Thermoelectrical responses can be improved by simultaneously tuning different properties within the material, such as nano structuring, nanocomposites, and doping. The purpose of this work is to determine the effect of single walled carbon nanotubes (SWCNT) on the thermoelectric properties of an n-type bismuth telluride alloy. Mechanical alloying and compaction sintering techniques are used to prepare SWCNT/Bi2Te2.55Se0.45 composites. Experiments are conducted with different concentrations (0.01, 0.025, 0.1 and 0.5 weight percent) and duration times of 20 hours. The results of the thermoelectric characteristics of SWCNT indicates that ball milling technique influences both its structure and agglomeration. The CNT filler is added during the step of mechanical milling, as this preserves SWCNT structure and increases its electrical conductivity. Additionally, it is demonstrated that SWCNT milling technique improves the Seebeck coefficient. While an increase in thermal conductivity is expected as a result of the high electrical conductivity due to increased scattering at the new interfaces, a significant drop in the lattice thermal conductivity is attained. The figure-of-merit for the optimal sample with 0.1 percent SWCNT added in 20 milling hours has improved by 13% at room temperature indicating a value of 0.3, and by 32% at 156.9°C indicating the highest ZT value of 0.6.

Due to the rapid growth of facial bone in the pediatric age group, the use of metallic plates would require a second surgical intervention to remove it. The alternative is biodegradable plating systems which are safe but not without complications, including learning curve, decreased stability, cost, and infection. The addition of hydroxyapatite to the synthesized thermoplastic polyurethane (TPU) may affect its structural and morphological properties. Hydroxyapatite is the inorganic part of the bone that is used as reinforcement in many applications. Plate systems comprising composites including hydroxyapatite (u-HA) particles have been developed for clinical use due to their osteoconductive capacity. The effects of hydroxyapatite addition on thermoplastic 'polyurethane's degradation, thermal, structural, and morphological characteristics were examined. This work aims to find an alternative material that can replace the commercial system used nowadays in bone fixation (made either from l-lactide or d-lactide) and overcome its disadvantages such as late degradation tissue response and foreign body reaction. The H12MDI based thermoplastic polyurethane was prepared using 12% HS 50:50 BD-Poly D, L-lactide -co-glycolide, then the composites were prepared by the addition of 3 and 15% of hydroxyapatite, respectively. The properties of the polymer and its composites have been characterized by Fourier transform spectroscopy (FTIR), carbon nuclear magnetic resonance (C13 NMR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and In vitro degradation analysis. It was found that the TPU is semi-crystalline and porous. The melting point and the decomposition temperature of the composites increased with the addition of HA compared to the pure TPU. with incubation in the buffer for 45 and 90 days. The melting point was found to be increased for the polymer as well as for the composites. SEM analysis showed that the polymer is porous, and the filler fills these pores in the composites, increasing its melting point and making the surface smoother. X-ray test showed that the crystallinity of the polymer raised with the addition of the filler. Regarding the degradation, the TPU showed a better degradation rate than the composites as it lost around 30%of its mass after two months only, while the composites lost about 10%. It was confirmed that the synthesized TPU-HA composite could be a promising candidate for bone repair systems.

Bismuth telluride chalcogenides are the ideal thermoelectric materials used for near room temperature applications. However, the usage of these materials is relegated to a few applications as a result of the extremely low heat conversion efficiencies. In this study, graphene is used as a nanofiller to prepare n-type bismuth telluride nanocomposite of a composition Bi2Te2.7Se0.3. The samples were prepared via a ball milling technique with different graphene concentrations and processing times. The results revealed that graphene addition during the last phase of milling improved the thermoelectric properties. However, these enhancements were limited to the lower graphene concentration of 0.05 wt.% only. Moreover, the figure-of-merit values of the optimum sample showed noticeable enhancements of 19%, reaching 0.5 at room temperature and 23 % at 160 ?C, reaching a maximum figure-of-merit value of 0.81. Hence, proving the ability of graphene to enhance the thermoelectric properties of the sample under study.

The state-of-the-art Bismuth Antimony Telluride (BiSbTe) alloys have a promising potential to advance thermoelectric applications in energy harvesting for efficient power generation and active refrigeration. In this thesis, the combination of High-Energy Ball Milling and FAST/SPS Sintering Press showed a reliable and cost effective synthesis approach for artifact-free nanostructured bulk BiSbTe/Graphene nanocomposites. The results show successfulness in synthesizing homogenous elemental distribution and stable single phase of Bi0.4Sb1.6Te3 either in the pristine nanopowder or the multicomponent nanocomposites. It also confirms the crucial rule of graphene addition time on its structure, as well as, the morphology, mechanical behavior, and thermoelectric performance of the synthesized nanocomposites. The 5mins nanocomposite showed an ultrahigh micro-hardness of 1.78GPa, the highest power factor of 1.73mW/m.K2 at 323K, and the lowest thermal conductivity of 0.723W/m.K at 323K. This has resulted in its optimum Figure-of-Merit of 0.70 at 323K with 25% of improvements compared to the pristine BiSbTe.

Thermoelectric technology converts thermal energy to electricity. Many studies were conducted on thermoelectric materials such as Bismuth Telluride and Lead Telluride. And the goal was to achieve an average ZT >2 which is required for waste heat recovery applications. Recently Tin Selenide (SnSe) showed a promising performance with a ZT of nearly 2.6 at 923 K for its single crystal structure at the b-axis. However, single crystal SnSe is very fragile and the production of single crystal SnSe structure is a complicated and costly process. Therefore, great interest was given to polycrystalline SnSe. In this work, the thermoelectric performance of polycrystalline SnSe was enhanced through nanostructuring and nano-composting with graphene via a cost-effective methodology. Nanocrystalline SnSe composites were successfully prepared by high energy ball milling and SPS techniques, and the structural characterization by X-ray Diffraction and Transmission Electron Microscopy revealed that the average grain size of both pristine SnSe and SnSe with Graphene was approximately (~ 10 nm). The mechanical properties were evaluated and showed an enhancement with high hardness values. The nanostructuring contributed in the enhancement of Seebeck coefficient and the highest reported value so far was obtained for pristine SnSe with 1032 μV/K at 873K. A significant improvement in ZT value was observed for the pristine nanostructured SnSe with a value of 0.9 at 873 K, and the addition of Graphene increased the ZT to 1.2 at 873 K due to the increased power factor and the lower thermal conductivity. Graphene was detected to be mainly present around the grain boundaries and this finding represents the first ever reported evidence to identify the location of graphene in a nanocrystalline TE material.

Nanocrystalline materials, those with grain size

Aluminum alloys in the conventional grain size state have had their share of research and are implemented in a variety of applications in our everyday life such as being the main structural materials in automobiles, aircrafts, solar panels supports and stations. Hence, it is long overdue to design light-weight aluminum alloys for the best performance in their nanostructured state. However, the strength associated with the reduced grain size of nanomaterials is associated with a penalty that leads to microstructural instabilities that result in grain growth, limiting their service temperatures and expected lifetime. Two mechanisms have been suggested to suppress grain growth: The first is a thermodynamic approach concerned with reducing the overall free energy of the system by lowering the grain boundary energy through solute segregation, and the second is kinetically by reducing grain boundary mobility. In this thesis, nanocrystalline (nc) Al and Al-2 at.% Li alloy are synthesized by mechanical cryomilling. It is proved that adding 1 at.% strontium (Sr) thermally stabilized the nc Al and its alloy up to 873 K, which represents 94% of its homologous temperature along with maintaining its exceptionally high hardness and good ductility, resulting in an alloy that has a specific strength higher than that of steel. Mechanical properties and thermal stability were studied through several characterization techniques such as XRD, TEM, micro-hardness, sheer punch tests, and SEM. It is concluded that thermal stabilization has occurred through both thermodynamic and kinetic mechanisms. Hence we anticipate that the results of this research will highly motivate the development of thermally stabilized, super-light and ultra-tough nanostructured materials for technological and structural applications.

Rare‐ earth (RE)‐doped III‐nitride broad band‐gap semiconductors have attracted enormous interest as a foundation for optoelectronics devices, which combine the unique luminescence feature of Rare‐earth ions with the electronic properties of the semiconductors. Recent progress toward nitride‐based light emitting diode and light emitting due to electric current devices have been made using crystalline and amorphous AlN and GaN doped with a different lanthanide elements. The Rare‐earth ions’ electronic structures are differ from the other elements and are unique due to an incompletely filled 4Fn shell. The 4F‐orbital electrons lay inside the ion and are protected from the surroundings by the filled 5S2 and 5P6 electron orbitals. When these rare‐earths doped are excited by any external means, intense sharp‐line emission is observed due to intra‐4Fn shells transitions of the rare‐earth ion core. In the present work, sputtered deposited thin films of AlN doped with rare‐earth elements (Sm, Ho, Gd, Tm) are investigated for their structures, luminescence and spectroscopic properties. Thin films were deposited at various temperatures. X‐ray diffraction (XRD) analysis was performed for structural analysis and crystallite size calculation in crystalline films. Scanning electron microscopy was also used to confirm the information obtained from XRD. Luminescence and spectroscopic analysis were performed using photoluminescence tool and Fourier transform infra‐red. The effect of the temperature on the surface morphology and luminescence properties was also studied. Energy dispersive x‐ray analysis was performed on the films to find the constituents and impurities in the samples. Atomic force microscopy was also used for determination of surface roughening, and thermal gravimetric analysis was used to investigate loss of mass of the samples over a range of temperature. This work provides investigations of these materials for their use in photonic and microelectronic devices.