Depistage De L’anemie En Urgence Au Chu Campus : Validation Du Degre De Concordance Entre Les Resultats De L’hemocue® Hb 301 Et Ceux Du Sysmex Xn-1000®

Introduction: Un dépistage fiable de l’anémié dans un contexte d’urgence grâce à un hémoglobinomètre de biologie délocalisée demeure un défis en Afrique. Le but de cette étude était d’évaluer le degré de concordance des résultats d’hémoglobinémie obtenus sur l’HemoCue® Hb 301 par rapport à ceux de l’analyseur Sysmex XN-1000®. Méthodes : Il s’est agi d’une étude rétrospective et transversale descriptive réalisée du 08 Mai 2017 au 23 Février 2018 au CHU Campus du Togo. La performance du Sysmex XN-1000®  a été confirmée grâce à l’évaluation de l’exactitude et de la fidélité de mesure. La performance de l’Hemocue® Hb 301 a été évaluée au moyen d’une régression linéaire et du diagramme de Bland et Altman vis-à-vis du Sysmex XN-1000®. Les critères de performances utilisés étaient ceux du Clinical Laboratory Improvement Amendments (CLIA) et de RICOS et al.  Résultats: Le niveau d’exactitude selon CLIA du Sysmex XN-1000® était de 100%. L’équation de la droite de régression était: Y (HemoCue® Hb 301) = 0,99x (Symex XN-1000®) + 0,54 g/dl. Les valeurs médianes des 100 échantillons sur le Sysmex et l’Hemocue étaient respectivement de 12,55 g/dl et 13,00 g/dl avec un biais médian de 3,58%, qui était inférieur au biais limite de ±7,0% (CLIA). Conclusion: Le Sysmex XN-1000® fournit des résultats d’hémoglobinémie interchangeables avec ceux de l’HemoCue® Hb 301, sans altération de la capacité diagnostique pour le patient. Il reste donc performant pour un quelconque dosage d’hémoglobinémie en urgence.  Introduction: Reliable anemia screening in an emergency setting, using a Point-of-care hemoglobinometer remains a challenge in Africa. The purpose of this study was to assess the degree of agreement between hemoglobin results obtained on the HemoCue® Hb 301 compared to those of the Sysmex XN-1000® Analyzer. Methods: This was a retrospective and cross-sectional descriptive study carried out from May 08 2017 to February 23, 2018 at the Campus teaching hospital of Togo. The performance of the Sysmex XN-1000® was confirmed by evaluating the measurement accuracy and precision. The performance of Hemocue® Hb 301 was assessed using linear regression and a Bland and Altman plot against Sysmex XN-1000®. The performance criteria used were those of Clinical Laboratory Improvement Amendments (CLIA) and RICOS et al. Results: The CLIA level of accuracy of the Sysmex XN-1000® was 100%. The equation for the regression line was: Y (HemoCue® Hb 301) = 0.99x (Symex XN-1000®) + 0.54 g / dl. The median values of the 100 samples on the Sysmex and Hemocue were 12.55 g / dl and 13.00 g / dl respectively, with a median bias of 3.58%, which was less than the borderline bias of ± 7.0 % of CLIA. Conclusion: The Sysmex XN-1000® provides interchangeable hemoglobin results with those of HemoCue® Hb 301, without altering the diagnostic ability for the patient. It therefore remains effective for any emergency dosage of hemoglobinemia

Comparative analysis of the counting of schistocytes by manual microscopy and automatic blood analyzer Sysmex XN-1000

The purpose of the study is comparison of the FRC% indicator determined on the Susmex XN-1000 analyzer with the results of microscopy and identification of factors affecting the final FRC% indicator determined on the Susmex XN-1000 analyzer in children with suspected TMA after bone marrow transplantation.Цель исследования - сравнение показателя FRC% определяемого на анализаторе Sysmeх XN-1000 с результатами микроскопии и выявлении факторов в периферической крови, влияющих на итоговый показатель FRC% определяемый на анализаторе Sysmeх XN-1000 у детей с подозрением на ТМА после трансплантации костного мозга

Generation–recombination noise in gallium nitride-based quantum well structures

Electronic noise has been investigated in AlxGa1−xN/GaN modulation-doped field-effect transistors of submicron dimensions, grown by molecular beam epitaxy techniques. Some 20 devices were grown on a sapphire substrate. Conduction takes place in the quasi-two-dimensional (2D) layer of the junction (xy plane) which is perpendicular to the triangular quantum well (z direction). A nondoped intrinsic buffer layer separates the Si-doped donors in the AlxGa1−xN layer from the 2D transistor plane. Since all contacts must reach through the AlxGa1−xN layer to connect internally to the 2D plane, parallel conduction through this layer is a feature of all modulation-doped devices. The excess noise has been analyzed as a sum of Lorentzian spectra and 1/fαnoise. The Lorentzian noise is ascribed to trapping of the carriers in the AlxGa1−xN layer. The trap depths have been obtained from Arrhenius plots of log(τT 2)versus 1000/T. Comparison with previous noise results for GaAs devices shows that: (a) many more trapping levels are present in these nitride-based devices and (b) the traps are deeper (farther below the conduction band) than for GaAs, as expected for higher band-gap materials. Furthermore, the magnitude of the noise is strongly dependent on the level of depletion of the AlxGa1−xN donor layer. We also note that the trap-measured energies are in good agreement with the energies obtained by deep level transient spectroscopy

Improvement of Thermal Cycling Resistance of AlxSi1−xN Coatings on Cu Substrates by Optimizing Al/Si Ratio

The effect of the elemental composition of AlxSi1−xN coatings deposited on Cu substrates by magnetron sputtering on their structure, mechanical properties and thermal cycling performance is studied. The coatings with Al-Si-N solid solution, two-phase (AlxSi1−xN nanocrystallites embedded in the SixNy tissue phase) and amorphous structure were obtained by varying Al/Si ratio. It is shown that polycrystalline coatings with a low Si content (Al0.88Si0.12N) are characterized by the highest thermal cycling resistance. While the coatings with a high and intermediate Si content (Al0.11Si0.89N and Al0.74Si0.26N) were subjected to cracking and spallation after the first cycle of annealing at a temperature of 1000 ◦C, delamination of the Al0.88Si0.12N coating was observed after 25 annealing cycles. The Al0.88Si0.12N coating also exhibited the best barrier performance against copper diffusion from the substrate. The effect of thermal stresses on the diffusion barrier performance of the coatings against copper diffusion is discussed

KORELASI ANTARA ABNORMALITAS WDF, WNR, RET SCATTERGRAM SYSMEX XN-1000 DAN INDEKS PARASITEMIA PENDERITA MALARIA DI RSUD MERAUKE DENGAN KONFIRMASI UJI PCR

Latar belakang: Malaria masih menjadi masalah kesehatan di dunia. Metode mikroskopis merupakan gold standar mendiagnosis malaria. Indeks parasit malaria perlu diketahui klinisi karena berkaitan dengan derajat keparahan infeksi dan respons terapi. Saat ini alat penganalisis hematologi otomatis dapat dipakai sebagai salah satu pendekatan diagnostik alternatif malaria. Selain untuk pemeriksaan darah lengkap rutin, Sysmex XN-1000 dapat mendeteksi Plasmodium malaria yang ditandai munculnya abnormalitas WDF, WNR dan RET scattergram. Tujuan Penelitian: mengetahui korelasi antara abnormalitas WDF, WNR, RET scattergram Sysmex XN–1000 dan indeks parasitemia penderita malaria di RSUD Merauke. Metode: Cross sectional observasional, dikerjakan November 2017-Februari 2018 di RSUD Merauke dan Lab. Malaria Study Group, Institute of tropical Disease Unair Surabaya. Total 65 sampel positif malaria hasil pemeriksaan mikroskopis selanjutnya diperiksakan darah lengkap rutin menggunakan Sysmex XN-1000 dan nPCR. Hasil dan Pembahasan: Ditemukan P. falciparum (21,5%), P. vivax (67,%), dan mixed Plasmodium (10,8%), namun spesies Plasmodium malaria (Pf dan Pv) tidak berkorelasi dengan indeks parasitemia (p=0,538). Abnormalitas WDF dan WNR scattergram lebih tinggi dibandingkan abnormalitas RET scattergram (80% vs 24,61%). P.vivax mendominasi munculnya abnormalitas WDF dan WNR scattergram, sedangkan P. falciparum mendominasi munculnya abnormalitas RET scattergram (40/44,90, % vs 9/14, 64,3%). Terdapat 55 sampel (80%) menunjukkan abnormalitas pada salah satu atau gabungan ketiga scattergram. Simpulan: Muncul tidaknya abnormalitas pada salah satu atau gabungan ketiga scattergram Sysmex XN-1000 berkorelasi dengan indeks parasitemia (Mann- Whitney test, p=0,037) dengan positivitas muncul abnormalitas scattergram adalah 84,6%

Strain-induced ordering in InxGa1-xN alloys

The energetics and thermodynamic properties of cubic (c-)InxGa1-xN alloys are investigated by combining first-principles total energy calculations, a concentration-dependent cluster-based model, and Monte Carlo simulations. The search for the ground-state energies leads to the conclusion that biaxial strain suppresses phase separation, and acts as a driving force for chemical ordering in c-InxGa1-xN alloys. Ordered superlattice structures, with composition xcongruent to0.5 and stable up to T=1000 K, arises as the relevant thermodynamic property of the strained alloy. We suggest that the In-rich phases recently observed by us in c-GaN/InxGa1-xN/GaN double heterostructures are ordered domains formed in the alloy layers due to biaxial strain. (C) 2003 American Institute of Physics.82244274427

Plasma-Assisted Growth and Characterization of Piezoelectric AlN and Sc(x)Al(1-x)N Films for Microwave Acoustic Sensor Applications

The use of surface acoustic wave (SAW) sensors in high temperature harsh environments such as those found in power plants, industrial manufacturing, or aerospace applications allows for monitoring of internal conditions at locations where traditional sensors do not operate or are unreliable. Surface acoustic wave resonator (SAWR) sensors are based on piezoelectric materials and feature a small passive low-profile self-powered design that can operate and wirelessly transmit data to monitor parameters such as temperature, pressure, or strain. SAWR sensors typically consist of a series of metal electrodes fabricated onto a bulk crystal piezoelectric such as langasite (La3Ga5SiO14). However, there are major advantages in using thin film piezoelectrics such as AlN and ScxAl1-xN rather than bulk single crystal piezoelectrics, including the ability to fabricate devices on a wider range of substrates allowing for greater tuning of devices properties. This thesis investigates the film growth, materials characterization, and surface acoustic wave resonator (SAWR) device behavior of AlN and ScxAl1-xN thin film piezoelectric materials. AlN has many properties that make it an ideal candidate for harsh environment SAW sensors, including the ability to remain piezoelectric up to 1200oC, stability in air up to 700oC, and relatively high phase velocity and low acoustic loss. In this work, piezoelectric AlN and ScxAl1-xN films were synthesized at 930oC using a nitrogen plasma-assisted e-beam evaporation growth method, and the influence of substrate preparation, Al flux, Sc flux, N-plasma flux, and the use of a TiN (111) seed layer were investigated. The films contain epitaxial (0002) oriented grains that yield piezoelectric coupling when integrated into SAWR devices, and the specific film growth parameters that determine epitaxial film quality are correlated with SAWR response and the film electromechanical coupling coefficient (k2). The piezoelectric strength of AlN can be enhanced by alloying with Sc to form a ScxAl1-xN film and this increases the magnitude of electromechanical coupling by up to 400%. ScxAl1-xN films were grown with Sc compositions ranging from 8% to 57% and the electromechanical coupling constant, k2, extracted from SAWR device measurements was found to be significantly increased compared to AlN. A prototype Sc0.13Al0.87N-based SAWR temperature sensor was fabricated and packaged at the Frontier Institute for Research in Sensor Technologies (FIRST) and tested on an exhaust baffle in the UMaine Steam Plant for over 1000 hours, demonstrating the transition of the research from a Technology Readiness Level of ‘experimental proof of concept’ to ‘system prototype demonstration in an operational environment’

A Method for Finding Structured Sparse Solutions to Non-negative Least Squares Problems with Applications

Demixing problems in many areas such as hyperspectral imaging and differential optical absorption spectroscopy (DOAS) often require finding sparse nonnegative linear combinations of dictionary elements that match observed data. We show how aspects of these problems, such as misalignment of DOAS references and uncertainty in hyperspectral endmembers, can be modeled by expanding the dictionary with grouped elements and imposing a structured sparsity assumption that the combinations within each group should be sparse or even 1-sparse. If the dictionary is highly coherent, it is difficult to obtain good solutions using convex or greedy methods, such as non-negative least squares (NNLS) or orthogonal matching pursuit. We use penalties related to the Hoyer measure, which is the ratio of the $l_1$ and $l_2$ norms, as sparsity penalties to be added to the objective in NNLS-type models. For solving the resulting nonconvex models, we propose a scaled gradient projection algorithm that requires solving a sequence of strongly convex quadratic programs. We discuss its close connections to convex splitting methods and difference of convex programming. We also present promising numerical results for example DOAS analysis and hyperspectral demixing problems.Comment: 38 pages, 14 figure