Single-oxygen-containing branched side chains are designed and used to solubilize n-type copolymers consisting of BDF (benzodifuranone), isatin, and thiophene-based units. We present a simple ...synthetic approach to side chains with varying linker distances between the backbone and the branching point. The synthetic pathway is straightforward and modular and starts with commercially available reagents. The side chains give rise to excellent solubilities of BDF-thiophene copolymers of up to 90 mg/mL, while still being moderate in size (26–34 atoms large). The excellent solubility furthermore allows high molar mass materials. BDF-thiophene copolymers are characterized in terms of optoelectronic and thermoelectric properties. The electrical conductivity of chemically doped polymers is found to scale with molar mass, reaching ∼1 S/cm for the highest molar mass and longest backbone-branching point distance.
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IJS, KILJ, NUK, PNG, UL, UM
GD 552 is a high proper motion star with the strong, double-peaked emission lines characteristic of the dwarf nova class of cataclysmic variable (CV) star, and yet no outburst has been detected ...during the past 12 yr of monitoring. We present spectroscopy taken with the aim of detecting emission from the mass donor in this system. We fail to do so at a level which allows us to rule out the presence of a near-main-sequence star donor. Given GD 552's orbital period of 103 min, this suggests that it is either a system that has evolved through the ∼80-minute orbital period minimum of CV stars and now has a brown dwarf mass donor, or that has formed with a brown dwarf donor in the first place. This model explains the low observed orbital velocity of the white dwarf and GD 552's low luminosity. It is also consistent with the absence of outbursts from the system.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
The CentriMag (Levitronix LLC, Waltham, MA, USA) ventricular assist device is a centrifugal pump designed for short-term support in patients with cardiogenic shock. In patients with restrictive ...physiology, there is some concern about the use of these devices due a very small ventricular cavity. We review the evolution of a 32-year-old woman with restrictive cardiomyopathy, moderate pulmonary hypertension, and severe biventricular systo-diastolic dysfunction in whom a biventricular Centrimag device was implanted due to a progressive clinical worsening.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract Introduction About half of patients with acute liver failure (ALF) show clinical signs of cerebral edema and intracranial hypertension. Neuroimaging diagnostics and electroencephalography ...have poor correlation with intracranial pressure measurement. Objective The objective of this study was to characterize the cerebral hemodynamics patterns with transcranial Doppler (TCD) sonography in patients with ALF. Method We studied 21 patients diagnosed with ALF, admitted to the intensive care unit (ICU) at the Centro de Investigaciones Médico Quirúrgicas of Cuba. All of these patients had a TCD performed on arrival at ICU, evaluating the following: systolic (SV), diastolic (DV), and medium (MV) flows velocities and pulsatility index (PI) in right middle cerebral artery (RMCA) via temporal windows. Results The sonographic patterns of cerebral hemodynamics were as follows: low-flow, 12 patients (57.1%); high resistance, 5 patients (23.8%); and hyperemic, 4 patients (19%). Patients who died while waiting had lower MV RMCA (56.1 vs 58.1 cm/s) and higher PI (1.71 vs 1.41) than patients who could undergo transplantation ( P = .800 and P = .787, respectively). Conclusions In patients diagnosed with ALF admitted to the ICU the predominating cerebral hemodynamic pattern was low-flow with resistance increase. The TCD was shown to be a useful tool in the initial evaluation for prognosis and treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Carrying out feasibility studies for combined heat and power (CHP) in buildings systems is one of the most important steps in the decision-making process. This paper compares the features of ...different software packages available in the market and some custom-built models. It also discusses the advantages and disadvantages of building one’s own application. The number of variables that need to be considered will depend on the level of accuracy and flexibility sought. Software packages are a good start, but they tend to be either overly simple or extremely complicated, and sometimes not very flexible. On the other hand, building custom-built generic models that include different technologies, unit sizes, control modes, market restrictions and benefits, can be a complex and laborious process, but will be more transparent to the user.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
17.
Kidney Failure After Heart Transplantation Escoresca Ortega, A.M; Ruíz de Azúa López, Z; Hinojosa Pérez, R ...
Transplantation proceedings,
10/2010, Volume:
42, Issue:
8
Journal Article, Conference Proceeding
Peer reviewed
Abstract Background and purpose Heart transplantation is a procedure with a high mortality rate. Altered kidney function (AKF) after a heart transplant is common. The purpose of this study was to ...determine the incidence of and associated factors for renal dysfunction among patients who underwent heart transplantation in our hospital between January 2006 and November 2008. Patients and methods This retrospective observational study was performed on all patients receiving a heart transplant between January 1, 2006 and November 15, 2008. The following variables were recorded: patient comorbidities, indication, presurgical urea and creatinine levels, donor variables, surgical procedure, and postoperative features. Results A total of 54 heart transplantations were performed with 68.5% of patients being male. The average age at transplant was 49.52 years (±13.45 y) and the mean weight 72.5 kg (±14.8 kg). Overall mortality was 28.30%. Of the 54 patients, 70.4% showed AKF during the first week after transplantation; 30.61% were in stage III according to the Acute Kidney Injury classification. There were no statistically significant differences between the group of patients with versus without renal failure, except for the extracorporeal surgery time, which was significantly longer among those patients who had AKF, and glycemia, which was also higher in the immediate postoperative period. Analysis of patient mortality showed no significant differences for the patients with AKF (80% vs 68.4%; P = 31). Conclusions The rate of acute kidney failure was high (70.4%), as was the use of chronic renal replacement therapy (28.85%), but it decreased considerably when followed over time.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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•Liquid crystals based on Benzotriazole, Benzoxadiazole and Benzothiadiazole were synthetized.•Target compounds showed wide ranges of calamitic mesomorphism (N, SmA, SmX, SmC).•BTZ ...exhibited higher photoluminescence efficiency in solution.•BOX and BTD presented more organized mesophases.•Quantum yields of the solutions are preserved in the form of thin films.
We report the molecular designing of non-symmetrical luminescent liquid crystals based on the 1,2,3-benzotriazole (BTZ), 2,1,3-benzoxadiazole (BOX) and 2,1,3-benzothiadiazole (BTD) heterocycles. The compounds showed stable nematic and smectic mesophases in a wide range of temperatures (between 70 and 170 °C). Translational order parameter investigations based on X-ray diffraction experiments demonstrated high ordered layers, closely dependent of the molecular structure and the smectic organization. The molecules exhibited intense photoluminescence under UV–vis light excitation in solutions. The emission spectrum for BTZ revealed a maximum in the blue region (447 nm), while BOX and BTD emit in the yellow one (around 550 nm). The fluorescence quantum yields of the BTZ-based derivatives solution are up to 64%, significantly higher than BOX and BTD. Moreover, in solid films, the efficiencies remained in the same range of solution. DFT calculations indicate dihedral angles of 24-30° between the benzazole-phenyl rings, which may suppress π-stacking and consequently reduce fluorescence quenching in the solid phase. This work contributes to general knowledge, where asymmetric cores improve mesophase stabilization and photoluminescence preservation in the solid state compared to their symmetric pairs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Recording of the three AB release steps with Raman spectroscopy.•AB behavior in the first release step with different heating rates, by means of PCA.•Molecular dynamics proposal of ...AB before the first release step.
Ammonia borane, as a source of hydrogen, has attracted much attention due to its high hydrogen content, low molecular weight, and high stability in solution. However, the process and enhancement of hydrogen release must be done practically under ambient conditions. For this work, Raman spectroscopy, principal component analysis (PCA), and molecular simulation were applied to study the hydrogen release process of ammonia borane. Three stages of release were observed from room temperature to 1300 °C. The shift, the appearance, and the disappearance of the Raman bands were evident in the whole process. In-situ monitoring of Raman and PCA, with four different heating rates between 70 and 130 °C, was done; ammonia borane showed visible variations in its first release step, in which a fast rate helped reduce distortion in the release process. Finally, molecular simulation of ammonia borane using the Density Functional Theory (DFT) in calculations showed that dihedral rotation and stretching of the hydrogen bonds can occur before the first release step.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Historic manure stockpiled (active from 1935 through 2018) in a repository mound approximately 15 m high with a 31,415.93 m2 footprint was sampled from various depths at six locations in an ...environmental assessment framework. The manure samples were analyzed for nutrient content to investigate potential application as a soil amendment to local fields in combination with biowaste disposal regulations. Results indicate that manure can be used as a soil amendment; however, different crops and land conditions require specific nutrients, and application must be determined accordingly. Likewise, the manure analysis did not indicate any negative issues that would disallow land application as a disposal option. In addition to limiting environmental soil boring into the manure repository, two-dimensional geophysical electrical resistivity imaging was performed to characterize and quantify the deposited manure. Based on those efforts, the material volume within the site's manure repository was calculated to be 611,942.354 cubic meters (m3). Finally, based on the geophysical results and the historical information about the manure's deposited volume in the study area, an estimation of the released landfill gases and its expected produced energy is presented.
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•Integrated approach for characterizing a waste disposal site and proposing future use•Nutrient content and potential application as a soil amendment to local fields•Using soil boring and a geophysical method to characterize and quantify the deposited wastes•Estimation of released landfill gases through geophysical survey and historical data
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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