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1.
Astron Astrophys ; 6092018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30078846

RESUMO

CONTEXT: C-cyanomethanimine (HNCHCN), existing in the two Z and E isomeric forms, is a key prebiotic molecule, but, so far, only the E isomer has been detected toward the massive star-forming region. Sagittarius B2(N) using transitions in the radio wavelength domain. AIMS: With the aim of detecting HNCHCN in Sun-like-star forming regions, the laboratory investigation of its rotational spectrum has been extended to the millimeter-/submillimeter-wave (mm-/submm-) spectral window in which several unbiased spectral surveys have been already carried out. METHODS: High-resolution laboratory measurements of the rotational spectrum of C-cyanomethanimine were carried out in the 100-420 GHz range using a frequency-modulation absorption spectrometer. We then searched for the C-cyanomethanimine spectral features in the mm-wave range using the high-sensitivity and unbiased spectral surveys obtained with the IRAM 30-m antenna in the ASAI context, the earliest stages of star formation from starless to evolved Class I objects being sampled. RESULTS: For both the Z and E isomers, the spectroscopic work has led to an improved and extended knowledge of the spectroscopic parameters, thus providing accurate predictions of the rotational signatures up to ~700 GHz. So far, no C-cyanomethanimine emission has been detected toward the ASAI targets, and upper limits of the column density of ~ 1011-1012 cm-2 could only be derived. Consequently, the C-cyanomethanimine abundances have to be less than a few 10-10 for starless and hot-corinos. A less stringent constraint, ≤ 10-9, is obtained for shocks sites. CONCLUSIONS: The combination of the upper limits of the abundances of C-cyanomethanimine together with accurate laboratory frequencies up to ~ 700 GHz poses the basis for future higher sensitivity searches around Sun-like-star forming regions. For compact (typically less than 1″) and chemically enriched sources such as hot-corinos, the use of interferometers as NOEMA and ALMA in their extended configurations are clearly needed.

2.
Phys Med ; 32(12): 1681-1689, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27570122

RESUMO

PURPOSE: To assess bladder spatial-dose parameters predicting acute urinary toxicity after radiotherapy for prostate cancer (PCa) through a pixel-wise method for analysis of bladder dose-surface maps (DSMs). MATERIALS & METHODS: The final cohort of a multi-institutional study, consisting of 539 patients with PCa treated with conventionally (CONV:1.8-2Gy/fr) or moderately hypo-fractionated radiotherapy (HYPO:2.2-2.7Gy/fr) was considered. Urinary toxicity was evaluated through the International Prostate Symptoms Score (IPSS) administered before and after radiotherapy. IPSS increases ⩾10 and 15 points at the end of radiotherapy (ΔIPSS⩾10 and ΔIPSS⩾15) were chosen as endpoints. Average DSMs (corrected into 2Gy-equivalent doses) of patients with/without toxicity were compared through a pixel-wise method. This allowed the extraction of selected spatial descriptors discriminating between patients with/without toxicity. Previously logistic models based on dose-surface histograms (DSH) were considered and replaced with DSM descriptors. Discrimination power, calibration and log-likelihood were considered to evaluate the impact of the inclusion of spatial descriptors. RESULTS: Data of 375/539 patients were available. ΔIPSS⩾10 was recorded in 76/375 (20%) patients, while 30/375 (8%) experienced ΔIPSS⩾15. The posterior dose at 12mm from the bladder base (roughly corresponding to the trigone region) resulted significantly associated to toxicity in the whole/HYPO populations. The cranial extension of the 75Gy isodose along the bladder central axis was the best DSM-based predictor in CONV patients. Multi-variable models including DSM descriptors showed better discrimination (AUC=0.66-0.77) when compared to DSH-based models (AUC=0.58-0.71) and higher log-likelihoods. CONCLUSION: DSMs are correlated with the risk of acute GU toxicity. The incorporation of spatial descriptors improves discrimination and log-likelihood of multi-variable models including dosimetric and clinical parameters.


Assuntos
Neoplasias da Próstata/radioterapia , Doses de Radiação , Radioterapia/efeitos adversos , Bexiga Urinária/efeitos da radiação , Idoso , Fracionamento da Dose de Radiação , Humanos , Masculino
3.
J Chem Phys ; 139(15): 154308, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24160514

RESUMO

The high-resolution infrared spectrum of monodeuterated diacetylene has been recorded in the 450-1100 cm(-1) spectral region by Fourier transform infrared spectroscopy. Seven new bands have been identified: the ν3 fundamental (C-C stretch), and the ν8 + ν9, ν7 + ν8, 2ν7, 2ν8, ν8 + ν9 - ν9, and ν6 + ν9 - ν9 combination, overtone, and hot bands. The assigned transitions, together with those previously reported for the fundamental bands [F. Tamassia, L. Bizzocchi, C. Degli Esposti, L. Dore, M. Di Lauro, L. Fusina, M. Villa, and E. Canè, Astron. Astrophys. 549, A38 (2013)], form a comprehensive data set which comprises more than 2500 ro-vibrational transitions, and involves all singly and most doubly excited vibrational states of DC4H lying below 1000 cm(-1). Rotational and vibrational l-type resonance effects among the sub-levels of excited bending states were considered in the analysis, which also included a careful treatment of the various anharmonic interactions coupling many vibrational states lying above 600 cm(-1). Reliable and unambiguous spectroscopic parameters were obtained for each investigated state, including the rotational and centrifugal distortion constants Bv and Dv, the l-type doubling parameter qt, the anharmonicity constants xL(89), xL(69), and the vibrational l-type terms r89, r69 for the v8 = v9 = 1 and v6 = v9 = 1 bend-bend combination states.

4.
Phys Chem Chem Phys ; 9(13): 1579-86, 2007 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-17429551

RESUMO

Pure rotational transitions of silicon monosulfide ((28)Si(32)S) and its rare isotopic species have been observed in their ground as well as vibrationally excited states by employing Fourier transform microwave (FTMW) spectroscopy of a supersonic molecular beam at centimetre wavelengths (13-37 GHz) and by using long-path absorption spectroscopy at millimetre and submillimetre wavelengths (127-925 GHz). The latter measurements include 91 transition frequencies for (28)Si(32)S, (28)Si(33)S, (28)Si(34)S, (29)Si(32)S and (30)Si(32)S in upsilon = 0, as well as 5 lines for (28)Si(32)S in upsilon = 1, with rotational quantum numbers J''< or = 52. The centimetre-wave measurements include more than 300 newly recorded lines. Together with previous data they result in almost 600 transitions (J'' = 0 and 1) from all twelve possible isotopic species, including (29)Si(36)S and (30)Si(36)S, which have fractional abundances of about 7 x 10(-6) and 4.5 x 10(-6), respectively. Rotational transitions were observed from upsilon = 0 for the least abundant isotopic species to as high as upsilon = 51 for the main species. Owing to the high spectral resolution of the FTMW spectrometer, hyperfine structure from the nuclear electric quadrupole moment of (33)S was resolved for species containing this isotope, as was much smaller nuclear spin-rotation splitting for isotopic species involving (29)Si. By combining the measurements here with previously published microwave and infrared data in one global fit, an improved set of spectroscopic parameters for SiS has been derived which include several terms describing the breakdown of the Born-Oppenheimer approximation. With this parameter set, highly accurate rotational frequencies for this important astronomical molecule can now be predicted well into the terahertz region.

5.
Ann Oncol ; 18(1): 158-162, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16971662

RESUMO

BACKGROUND: Very limited experiences have explored the use of pain intensity monitoring in everyday clinical practice at a medical oncology inpatient unit. METHODS: The program 'Pain-Free Hospital,' including a training course for nurses and the recording every 12 h of a visual analog scale (VAS) rating in all the patients admitted to the inpatients' ward independently of their disease stage, was activated in 2002. An audit on the clinical charts of patients admitted for the first time in the first semester of 2003 was carried out in order to ascertain the applicability of the procedure and its congruence with patients' clinical status. RESULTS: The VAS rating was reported in 211 out of 223 (94.6%) clinical charts. At entry, 60 out of 211 (28.4%) patients presented VAS>or=1, 21 (35%) of whom were not taking any analgesics. The mean VAS score>or=1 was 3.4. No statistically significant difference emerged in the distribution of VAS rating as regards disease extension, presence or absence of bone metastases and performance status. CONCLUSIONS: The systematic monitoring of VAS by nurses at a medical oncology inpatients' ward is feasible with a good patient compliance. The reliability of the procedure in terms of guiding the analgesic treatment has yet to be demonstrated.


Assuntos
Neoplasias/complicações , Dor/diagnóstico , Idoso , Analgésicos/uso terapêutico , Estudos de Viabilidade , Feminino , Humanos , Pacientes Internados , Masculino , Oncologia , Neoplasias/fisiopatologia , Auditoria de Enfermagem , Recursos Humanos de Enfermagem Hospitalar/educação , Avaliação de Resultados em Cuidados de Saúde , Dor/tratamento farmacológico , Dor/etiologia , Medição da Dor , Fatores de Tempo
6.
J Mol Spectrosc ; 205(1): 164-172, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11148120

RESUMO

The rotational spectra of the unstable HCCCP molecule have been investigated in the millimeter-wave region for the main excited vibrational states which lie below 1000 cm(-1), namely nu(4) (C&bond;C stretch), nu(5) (HCC bend), nu(6) (CCC bend), nu(7) (CCP bend), 2nu(6), 2nu(7), 3nu(7), 4nu(7), nu(5) + nu(7), and nu(6) + nu(7). l-type resonance effects have been taken into account in the analysis of the spectra, so that the values of the anharmonicity constants x(L(66)), x(L(77)), x(L(57)), and x(L(67)) could be determined. The anharmonic interactions which couple the nu(4) state with nu(6) + nu(7), 2nu(6), and 4nu(7) have been also considered, yielding the unperturbed value of the alpha(4) vibration-rotation coupling constant. Copyright 2001 Academic Press.

7.
J Mol Spectrosc ; 199(1): 109-115, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10712877

RESUMO

FT infrared spectra of BrCN have been recorded in the region of the nu(2) band near 340 cm(-1), the nu(1) band near 580 cm(-1), and the 2nu(2) band near 690 cm(-1) with a resolution between 2.9 and 4.7 x 10(-3) cm(-1). The vibrational levels (01(1)0), (10(0)0), (02(0)0), (02(2)0), (11(1)0), and (20(0)0) have been analyzed employing cold bands, hot bands, and new millimeter-wave transitions. Band-by-band polynomial analyses and a combined fit of all data relevant to the 2v(1) + v(2) = 2 polyad levels have been performed. The latter fit considered l-resonance interactions between the (02(0)0), e and (02(2)0), e levels and Fermi resonance between the two Sigma states (10(0)0) and (02(0)0). Altogether about 1000 pieces of data up to J = 100 were fitted for each of the two isotopic species with rms of the residuals of 2-8 x 10(-4) cm(-1) for the infrared and 10-120 kHz for the pure rotational data. Copyright 2000 Academic Press.

8.
J Mol Spectrosc ; 204(2): 275-280, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11148096

RESUMO

The rotational spectra of (32)S(35)Cl(2), (32)S(35)Cl(37)Cl, (32)S(37)Cl(2), and (34)S(35)Cl(2) in their ground vibrational states, as well as those of (32)S(35)Cl(2) and (32)S(35)Cl(37)Cl in their nu(2) and 2nu(2) excited states, have been studied in selected frequency regions between 100 and 370 GHz. Transitions involving a large range of quantum numbers have been observed, so that precise rotational and quartic centrifugal distortion constants could be determined for each of the spectra investigated. The complete set of sextic distortion constants was also obtained for the most abundant isotopomer in its ground vibrational state. The newly determined rotational constants of (34)S(35)Cl(2) and (32)S(37)Cl(2) allowed us to calculate the complete r(s) structure of sulfur dichloride using both single- and double-isotopic substitution methods. The quadratic force field has been refined using a larger set of quartic distortion constants and inertial defects. Copyright 2000 Academic Press.

9.
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