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We present a compact freeform optic, called "Freeform Shell-Mixer", which, when placed on top of a multicolor light source (particularly, a multi-chip LED), turns it into a virtual source in which colors are uniformly mixed. The optic, compatible with injection molding, makes use of étendue-conserving Köhler integration to provide homogeneous mixing of light. Its minimal size (just 2x larger than the source) makes the concept compatible with many luminaries, as ray tracing models show. Simulations indicate that the Freeform Shell-Mixer can reach efficiencies above 95% and both the size of the virtual source and its emission pattern are very similar to the ones of the original source, so the correct performance of the luminaire is secured.

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PURPOSE: The purpose of our study was to evaluate the significance of multifocal (MF) and multicentric (MC) breast cancer in the diagnosis and treatment of this condition. METHODS: This retrospective study was a combination of clinical and laboratory data. The patient population consisted of 274 women operated on with Madden mastectomy for breast cancer. Assessed were the following parameters: age, menstrual status, histopathological parameters, HER-2 status, estrogen receptor (ER) and progesterone receptor (PR) status, disease stage, quadrant(s) in which breast cancer was detected and axillary lymph nodes status. RESULTS: Of 274 patients 206 (85%) has unifocal disease, 41 (15%) suffered of MF (n=27; 9.9%)/MC (n=14; 5.1%) disease. MC disease was associated with metastatic axillary lymph nodes in 92.9% of the cases. MF/MC cases were primarily dependent on histology. MF/MC cancer was best related to the lobular type (85.7% of the cases), while ductal histological type was characteristic of unifocal tumors. CONCLUSION: Quadrantectomy as a form of conservative breast surgery is acceptable in cases of MF tumors, because all tumor foci can be removed. We suggest radical surgical treatment in all cases of suspected MC tumors because they are most often associated with metastasis to the axillary lymph nodes. Lobular histology characterizes MC breast cancer.

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PURPOSE: To compare the efficacy, toxicity and survival of cisplatin monotherapy with concurrent radiotherapy ver-sus combination of cisplatin and 5-fluorouracil (5-FU) with concurrent external beam radiotherapy (EBRT) in patients with locoregionally advanced cervical carcinoma FIGO stages IIB-IV. METHODS: 134 patients with locoregionally advanced, histologically confirmed carcinoma of the uterine cervix were analysed. The first group of patients (n=70; 52.24%) started concomitant chemotherapy on the second day of radiotherapy with single-agent cisplatin 40 mg/m(2) given 2 h before radiotherapy, once a week for 6 courses. The second group of patients (n=64; 47.76%) started concomitant chemotherapy on the second day of radiotherapy with cisplatin 75 mg/m(2). Treatment was continued with 96-h infusion of 5-FU 4 g/m(2) (1 g/ m(2) per day for 5 consecutive days). The patients were irradiated by EBRT followed by intracavitary brachytherapy (ICB). RESULTS: 24- and 42-month survival in the first group were 71.9 and 57.81% and 52.5 and 35.4% in the second group, respectively (p=0.012). Mean time to progression in the first group was 24 months and in second group it was 15.9 months (p=0.012). After 2 years progression was noted in 38.3% of the first and in 62.9% of second group patients (p=0.003). After 40 months 60 patients were without relapse, 35 (57.81%) patients in the first group and 25 (37.147percnt;) patients in the second group (p=0.018). CONCLUSION: Treatment with combined cisplatin and 5-FU with concurrent EBRT was more efficient in comparison to cisplatin monotherapy with concurrent radiotherapy in patients with locoregionally advanced cervical carcinoma, in terms of 12- and 24-month overall survival and disease relapse after 2 years.

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Adsorption characteristics of native and cross-linked lysozyme crystals were examined using fluorescein as model adsorbate. The adsorption isotherms exhibited Langmuir or linear behavior. The affinity constant (b1) and the adsorption capacity (Qsat) for fluorescein were found to depend on the type and concentration of co-solute present in the solution. The dynamics of adsorption isotherm transition from Langmuir to linear showed that affinity of lysozyme for solutes increases in the order 2-(cyclohexylamino)ethanesulphonic acid (CHES), 4-morpholinepropanesulphonic acid (MOPS), acetate, fluorescein. Furthermore, the crystal morphology, the degree of cross-linking of the crystals, and, in particular, solution pH were identified as factors determining fluorescein adsorption by the lysozyme crystals. These factors seem to affect crystal capacity for the solute more than affinity for the solute. Adsorption of fluorescein by cross-linked tetragonal lysozyme crystals was exponentially dependent on the lysozyme net charge calculated from the final solution pH. The 3-5-fold increase in the fluorescein adsorption as a result of cross-linking is presumably due to the increasing hydrophobicity of the lysozyme crystal.

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The diffusion of a solute, fluorescein into lysozyme protein crystals has been studied by confocal laser scanning microscopy (CLSM). Confocal laser scanning microscopy makes it possible to non-invasively obtain high-resolution three-dimensional (3-D) images of spatial distribution of fluorescein in lysozyme crystals at various time steps. Confocal laser scanning microscopy gives the fluorescence intensity profiles across horizontal planes at several depths of the crystal representing the concentration profiles during diffusion into the crystal. These intensity profiles were fitted with an anisotropic model to determine the diffusivity tensor. Effective diffusion coefficients obtained range from 6.2 x 10(-15) to 120 x 10(-15) m2/s depending on the lysozyme crystal morphology. The diffusion process is found to be anisotropic, and the level of anisotropy depends on the crystal morphology. The packing of the protein molecules in the crystal seems to be the major factor that determines the anisotropy.

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The failure of urorectal septum to form and divide the cloaca into rectum dorsally, and urogenital sinus ventrally, results in a cloacal dysgenesis. It is an extremely rare anatomic malformation of the genito-urinary tract and alimentary tract. A case of pregnancy and vaginal delivery in a patient with cloacal dysgenesis type II and previous heart operation is presented. Both mother and newborn were in good condition. The way of treatment of such patients is discussed.

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The TRISS method has been claimed to be useful in the evaluation of trauma care. The aim of this study was to compare our data with Major Trauma Outcome Study (MTOS) results in North America, and to note differences and strive to improve care in our system. Data were collected from 163 consecutively admitted trauma patients to the Intensive Care Unit, Accident and Emergency Centre, Belgrade, Yugoslavia. Systolic blood pressure, respiration rate and Glasgow Coma Score were obtained on admission and the Abbreviated Injury Score was presented by anatomical area. Data were analysed on an Amstrad PCW computer, using a special non-commercial program. The calculated expected survival out of 163 cases was 131.7 and observed 111 patients. Distribution of severity of injury of the study population had a greater severity of injury than did the baseline. Thus, although the observed survival was less than expected, this is not conclusive evidence of worse care. This applies especially to the group of patients over 54 years of age who suffered blunt trauma, whose higher mortality (23 observed and 15.6 expected out of 50 patients) can be attributed to the ISS score being almost double that of the MTOS population of comparable age. Penetrating trauma patients, in spite of severe injuries, had better survival than predicted. The TRISS method, in spite of its limitations, proved a useful method of evaluating trauma care, and can be run on a small computer without the necessity for special staff.

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Fluorescence parameters were reported earlier to be reliable indicators in the determination of heavy metal toxicity in algal cultures (Samson and Popovic, 1988). In this report, the effects of copper on Selenastrum capricornutum culture growth and photosynthetic efficiency were studied at different copper concentrations. By using the complementary area of variable fluorescence kinetics and the cell counting method, we determined the level of toxicity at different copper concentrations and the ability of algal populations to adapt to inhibitory effects. Algae exposed to copper concentrations higher than 0.5 mg/liter were incapable of recovering biochemical and physiological processes related to photosynthesis after 96 hr. A recovery process in algal culture intoxicated with 0.5 mg/liter was revealed only by fluorescence induction phenomena. Here, the authors justify the use of fluorescence induction parameters in the investigation of copper stress effects on algal populations and their short-term adaptation phenomena.

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Treatment with SQ 14.225, an inhibitor of the enzyme converting angiotensin I to angiotensin II and lowering of plasma renin activity by dietary salt overload, significantly decreased hypertrophy of the right ventricle in chronically hypoxic rats. The smaller degree of right ventricular hypertrophy registered in hypoxic rats with suppressed activity of the renin-angiotensin system was proportional to the decrease in hypoxic pulmonary hypertension noted in these animals. Lowering of pulmonary hypertension in chronically hypoxic rats by suppression of the renin-angiotensin system is consistent with the idea that angiotensin II may be involved in eliciting hypoxic pulmonary vasoconstriction. Inhibition of converting enzyme also lowered the systemic arterial pressure in hypoxic rats, but this finding could not be taken as evidence for the role of the renin-angiotensin system in homeostatic control of blood pressure in normal animals, since the plasma-renin activity in hypoxic rats is increased and the blood pressure higher than in rats kept under normoxic conditions.

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