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OBJECTIVE: Glycemia management in critical care is posing a challenge in frequent measuring and adequate insulin dose adjustment. In recent years, continuous glucose measurement has gained accuracy and reliability in outpatient and inpatient settings. The aim of this study was to assess the feasibility and accuracy of real-time continuous glucose monitoring (CGM) in ICU patients after major abdominal surgery. RESEARCH DESIGN AND METHODS: We included patients undergoing pancreatic surgery and solid organ transplantation (liver, pancreas, islets of Langerhans, kidney) requiring an ICU stay after surgery. We used a Dexcom G6 sensor, placed in the infraclavicular region, for real-time CGM. Arterial blood glucose measured by the amperometric principle (ABL 800; Radiometer, Copenhagen, Denmark) served as a reference value and for calibration. Blood glucose was also routinely monitored by a StatStrip bedside glucose meter. Sensor accuracy was assessed by mean absolute relative difference (MARD), bias, modified Bland-Altman plot, and surveillance error grid for paired samples of glucose values from CGM and acid-base analyzer (ABL). RESULTS: We analyzed data from 61 patients and obtained 1,546 paired glucose values from CGM and ABL. Active sensor use was 95.1%. MARD was 9.4%, relative bias was 1.4%, and 92.8% of values fell in zone A, 6.1% fell in zone B, and 1.2% fell in zone C of the surveillance error grid. Median time in range was 78%, with minimum (

Św. Tomasz z Akwinu (1224–1274) interesował się filozofią muzułmańską oraz arabskimi przekładami Arystotelesa, dlatego tematyka wpływu filozofii muzułmańskiej na koncepcje Akwinaty była wielokrotnie poddawana wnikliwej analizie. Obecne opracowanie nie podejmuje tematyki związanej z filozoficznymi inspiracjami, które zaczerpnął Akwinata od myślicieli muzułmańskich, ale stanowi próbę ukazania jego wiedzy i stanowiska, jakie zajmował wobec islamu i muzułmanów. Artykuł bazuje głównie na trzech dziełach Doktora Kościoła: Summa contra Gentiles („Suma przeciw poganom”), De rationibus Fidei („O racjonalności wiary”) oraz Summa Theologiae („Suma teologiczna”). Cel niniejszego artykułu stanowi próba przedstawienia całościowej wizji Akwinaty na temat islamu i jego wyznawców. Artykuł ukazuje również, z jakimi trudnościami mierzyli się średniowieczni teolodzy chrześcijańscy w zetknięciu z islamem.

A model of α-Mg grain growth in an amorphous Mg72Zn28 alloy matrix was developed together with numerical software. Its application enables tracking the growth process of the α-Mg phase in an amorphous alloy. The model was based on the diffusion-driven growth of α-Mg in an amorphous alloy under appropriate boundary conditions at an isothermal annealing temperature and taking into account the presence of a grain with an initial radius of 1 nm. The numerical model was based on a mathematical model of heat flow, described by the Fourier–Kirchhoff equation, and diffusion, described by Fick’s second law. The initial boundary conditions necessary to simulate grain growth in the amorphous phase were established. The results of the numerical simulation indicate grain growth with increasing isothermal annealing temperature and increasing isothermal annealing time.

St. Thomas Aquinas (1224-1274) was interested in Muslim philosophy and Arabic translations of Aristotle. Therefore, the subject of the influence of Muslim philosophy on Aquinas' concepts has been analyzed in depth many times. The present study does not take up the subject of the philosophical inspirations which Aquinas took from Muslim thinkers but is an attempt to show his knowledge and the position he took towards Islam and the Muslims. The article is mainly based on three works of the Doctor of the Church: Summa contra Gentiles (Summa against the Gentiles), De rationibus Fidei (On the Rationality of Faith) and Summa Theologiae (Theological Summa). The purpose of this article is to present Aquinas' overall vision of Islam and its followers. The article also shows what difficulties medieval Christian theologians faced when confronted with Islam. [ABSTRACT FROM AUTHOR]

BackgroundInfections remain a major cause of morbidity and mortality after kidney transplantation. The aim of our study was to determine the effect of sepsis on kidney graft function and recipient mortality.MethodsA prospective, observational, single-center study was performed. Selected clinical and biochemical parameters were recorded and compared between an experimental group (with sepsis, n = 34) and a control group (with systemic inflammatory response syndrome, n = 31) comprising kidney allograft recipients.ResultsSepsis worsened both patient (HR = 14.77, p = 0.007) and graft survival (HR = 15.07, p = 0.007). Overall one-year mortality was associated with age (HR = 1.08, p = 0.048), APACHE II score (HR = 1.13, p = 0.035), and combination immunosuppression therapy (HR = 0.1, p = 0.006), while graft survival was associated with APACHE II (HR = 1.25, p = 0.004) and immunosuppression. In sepsis patients, mortality correlated with the maximal dose of noradrenalin (HR = 100.96, p = 0.008), fungal infection (HR = 5.64, p = 0.024), SAPS II score (HR = 1.06, p = 0.033), and mechanical ventilation (HR = 5.97, p = 0.033), while graft survival was influenced by renal replacement therapy (HR = 21.16, p = 0.005), APACHE II (HR = 1.19, p = 0.035), and duration of mechanical ventilation (HR = 1.01, p = 0.015).ConclusionIn contrast with systemic inflammatory response syndrome, septic kidney allograft injury is associated with early graft loss and may represent a significant risk of mortality.

The structure of the antiferroelectric smectic CA phase is investigated for two liquid crystals with almost identical molecular structures, except for chiral centers. The X-ray diffraction results determined the crystal unit cell parameters, smectic layer spacing, average distance within layers, and correlation length of the short-range positional order. The coefficients of thermal expansion are determined for the crystal phases. The molecular modeling with the semi-empirical PM7 method and density functional theory calculations with the def2TZVPP basis set and B3LYP-D3(BJ) functional are applied to determine the tilt angle of molecules from the experimental smectic layer spacing. The most probable conformations are then selected based on a comparison with the tilt angle measured by the electro-optic method, known from the previous results. In the most suitable molecular models, the chiral chain makes an approximately 90° angle with the molecular core, and some fragments in the fluorinated part of the achiral terminal chain are in the gauche conformation. [ABSTRACT FROM AUTHOR]

The influence of the hold time of the austempering heat treatment at 280°C on the microstructure and corrosion resistance in NaCl-based media of austempered ductile iron was investigated using X-ray diffraction, micro-hardness measurements, corrosion tests and surface observations. Martensite was only found in the sample which was heat treated for a short period (10 minutes). Corrosion tests revealed that this phase does not play any role in the anodic processes. Numerous small pits were observed in the α-phase which is the precursor sites in all samples (whatever the value of the hold time of the austempering heat treatment).

The article presents research aimed at determining the effect of adding rare earth elements to near-eutectic Al-Si and Al-Si-Ni alloys on the microstructure and mechanical properties of the obtained products. Material for the research was prepared using a melt spinner – a device used for rapid crystallization, casting thin ribbons, which were then subjected in subsequent stages to fragmentation, consolidation and plastic working. The ribbons and extruded rods cast were described in terms of their structure and their strength properties were determined at different measurement temperatures. It was shown that the lightweight materials produced from aluminium alloys using the rapid solidification process have an ultra-fine structure and good strength properties. Analysis under a microscope confirmed that the addition of rare earth alloys Al-Si and Al-Si-Ni causes fragmentation of the microstructure in the tapes produced. The presence of rare earth elements in the alloys tested has an impact on the type and the morphology of the particles of the microstructure’s individual components. In addition to the change in particle morphology, the phenomenon of the separation of numerous nanometric particles of intermetallic phases containing rare earth elements was also observed. The change in microstructure caused by the addition of rare earth elements in the form of a mischmetal increases the mechanical properties.

The aim of this work is to develop a numerical model capable of predicting the grain density in the Mg-based matrix phase of an AZ91/SiC composite, as a function of the total mass fraction of the embedded SiC particles. Based on earlier work in a range of alloy systems, we assume an exponential relationship between the grain density and the maximum supercooling during solidification. Analysis of data from cast samples with different thicknesses, and mass fractions of added SiCp, permits conclusions to be drawn on the role of SiCp in increasing grain density. By fitting the data, an empirical nucleation law is derived that can be used in a micro model. Numerical simulation based on the model can predict the grain density of magnesium alloys containing SiC particles, using the mass fraction of the particles as inputs. These predictions are compared with measured data.

In this study, thin ribbons of amorphous Mg72Zn27Pt1 and Mg72Zn27Ag1 alloys with potential use in biomedicine were analyzed in terms of the crystallization mechanism. Non-isothermal annealing in differential scanning calorimetry (DSC) with five heating rates and X-ray diffraction (XRD) during heating were performed. Characteristic temperatures were determined, and the relative crystalline volume fraction was estimated. The activation energies were calculated using the Kissinger method and the Avrami exponent using the Jeziorny–Avrami model. The addition of platinum and silver shifts the onset of crystallization towards higher temperatures, but Pt has a greater impact. In each case, E g > E x > E p (activation energy of the glass transition, the onset of crystallization, and the peak, respectively), which indicates a greater energy barrier during glass transition than crystallization. The highest activation energy was observed for Mg72Zn27Pt1 due to the difference in the size of the atoms of all alloy components. The crystallization in Mg72Zn27Ag1 occurs faster than in Mg72Zn27Pt1, and the alloy with Pt has higher (temporary) thermal stability. The Avrami exponent (n) values oscillate in the range of 1.7–2.6, which can be interpreted as one- and two-dimensional crystal growth with a constant/decreasing nucleation rate during the process. Moreover, the lower the heating rate, the higher the nucleation rate. The values of n for Mg72Zn27Pt1 indicate a greater number of nuclei and grains than for Mg72Zn27Ag1. The XRD tests indicate the presence of α-Mg and Mg12Zn13 for both Mg72Zn27Pt1 and Mg72Zn27Ag1, but the contribution of the Mg12Zn13 phase is greater for Mg72Zn27Ag1 [ABSTRACT FROM AUTHOR]

The main aim of this work was to numerically investigate and optimize feeding and geometrical parameters to produce inlet valves of Ti6Al4V alloy that are free from defects, especially porosity. It was found that the change of geometry orientation as well as inlet feeder diameter and angle showed distinct relationships between geometric alteration and occurrence of porosity. Alteration in the pouring parameters such as temperature and time had none or only slight effect on occurrence or position of porosity in the valve. It was also found that investigating individual parameters of simple geometry and then utilizing these best fit results in complex geometry yielded beneficial results that would otherwise not be attainable.

An experimental investigation was conducted to observe and analyze the microstructural evolution of phases present in the AK64 Al-Si-Cu alloy subjected to a modified T6 heat treatment (HT). The AK64 alloy1 is the Polish alternative of the A319.0 ASM standard aluminium alloy. The modified T6 HT schedule with a higher temperature and shorter duration was applied in the solutioning process and lower quenching and higher artificial ageing temperature than the prescribed by the ASM standard were used. The cooling curves registered during the liberating of overheating and solidifying processes give important information on nucleation temperatures for the Al dendrite network, Al-Si eutectic reaction and precipitation of Cu-rich phases. Comparison of the as-cast and heat treated microstructures revealed predicted microstructural changes and also partial fragmentation of the Fe-rich phases was observed after the application of the modified HT programme.

The behaviour of non-metallic particles in the selected composites was analysed, in the current study. The calculations of particles floating in liquids differing in viscosity were performed. Simulations based on the Stokes equation were made for spherical SiC particles and additionally the particle size influence on Reynolds number was analysed.The movement of the particles in the liquid metal matrix is strictly connected with the agglomerate formation problem.Some of collisions between non-metallic particles lead to a permanent connection between them. Creation of the two spherical particles and a metallic phase system generates the adhesion force. It was found that the adhesion force mainly depends on the surface tension of the liquid alloy and radius of non-metallic particles.

The presented work focuses on solid particle interactions with the moving crystallization front during a solidification of the metal matrix composite. The current analyses were made for silicon carbide particles and ZnAl alloy with different additions of aluminium. It was found, that the chemical composition of the metal matrix influences the behaviour of SiC particles. At the same time calculations of the forces acting on a single particle near the crystallization front were performed. For each alloy type the critical conditions that determine whether particle will be absorbed or pushed, were specified.

The process of manganese sulfide formation in the course of grain-oriented silicon steel solidification process is described in the paper. Fine dispersive MnS inclusions are grain growth inhibitors and apart from AlN inclusions they contribute to the formation of a privileged texture, i.e. Goss texture. A computer simulation of a high-silicon steel ingot solidification with the use of author’s software has been performed. Ueshima model was adapted for simulating the 3 % Si steel ingot solidification. The calculations accounted for the back diffusion effect according to Wołczyński equation. The computer simulation results are presented in the form of plots representing the process of steel components segregation in a solidifying ingot and curves illustrating the inclusion separation process.

Polarizing optical microscopy is used to investigate the isothermal and non-isothermal crystallization of the 3F6FPhF6 compound, which exhibits the smectic C* and smectic CA* phases. A large hysteresis of above 20 K in the smectic C*/smectic CA* phase transition is reported. The kinetics of non-isothermal crystallization is analyzed by means of the continuous cooling transition diagram. The cooling rate necessary for at least partial vitrification of the smectic CA* phase is estimated. The relationship between the thermodynamic driving force of crystallization and thermal energy of the translational degrees of freedom is shown to have a strong impact on crystallization. [ABSTRACT FROM AUTHOR]

The aim in this work is to develop a log-normal distribution of heterogeneous nucleation substrates for the composite based on AZ91 alloy reinforced by SiC particles. The computational algorithm allowing the restore of the nucleation substrates distribution was used. The experiment was performed for the AZ91 alloy containing 1 % wt. of SiC particles. Obtained from experiment, the grains density of magnesium primary phase and supercooling were used to algorithm as input data.

The formation of glass of the anticlinic high-tilted smectic CA* phase even at low cooling rates (≥2 K min−1) is reported for (S)-4′-(1-ethylhexyloxycarbonyl)biphenyl-4-yl 4-[5-(2,2,3,3,4,4,4-heptafluorobutoxy)pentyl-1-oxy]benzoate. The kinetics of crystallization is investigated via differential scanning calorimetry, polarizing optical microscopy and broadband dielectric spectroscopy. The temperature region of the largest crystallization rate, the activation energy of cold crystallization and the energy barrier of nucleation are determined. The coupling of the characteristic crystallization time with the α-relaxation time is studied. A high fragility index equal to 139 is obtained for this glassformer. Comparison with a very similar glassforming compound, with the chiral centre based on (S)-(+)-2-octanol instead of (S)-(+)-3-octanol, is presented. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyze the crystallization kinetics of the Mg72Zn28 metallic glass alloy. The crystallization kinetics of Mg72Zn28 metallic glass were investigated by differential scanning calorimetry and X-ray diffraction. The phases formed during the crystallization process were identified as α-Mg and complex Mg12Zn13 phases. Activation energies for the glass transition temperature, crystallization onset, and peak were calculated based on the Kissinger model. The activation energy calculated from the Kissinger model was Eg = 176.91, Ex = 124.26, Ep1 = 117.49, and Ep2 = 114.48 kJ mol−1, respectively. [ABSTRACT FROM AUTHOR]