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Noise annoyance due to railway traffic is a growing issue in today's society. This annoyance may be predicted using noise-exposure relationships with mean energy-based index. However, there is room for improvement of models as other acoustical and non-acoustical factors also influence noise annoyance responses. In this paper, it is proposed to highlight annoying auditory sensations evoked by the railway noise and determine acoustical and psychoacoustical indices combined in a predictive model. A laboratory experiment involving railway pass-by noise in urban areas was carried out. Annoyance ratings, noise sensitivity ratings, and free verbalization data were gathered. The analysis underlined annoying auditory sensations caused by railway pass-by noises. Two indices were proposed to account for irregular amplitude fluctuation and noise event duration-related sensations. A multilevel regression analysis was conducted, leading to two annoyance models considering noise indices and noise sensitivity. These models were finally compared to a similarly obtained multilevel regression model related to tramway noise annoyance. The comparison was carried out as a cross-validation considering the models and the respective datasets collected in laboratory conditions for model construction. Results showed that the railway noise annoyance model led to a good prediction of tramway noise annoyance and vice versa.
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In this paper, we study band-to-band and intersubband (ISB) characteristics of Si- and Ge-doped GaN/AlN heterostructures (planar and nanowires) structurally designed to absorb in the short-wavelength infrared region, particularly at 1.55 µm. Regarding the band-to-band properties, we discuss the variation of the screening of the internal electric field by free carriers, as a function of the doping density and well/nanodisk size. We observe that nanowire heterostructures consistently present longer photoluminescence decay times than their planar counterparts, which supports the existence of an in-plane piezoelectric field associated to the shear component of the strain tensor in the nanowire geometry. Regarding the ISB characteristics, we report absorption covering 1.45-1.75 µm using Ge-doped quantum wells, with comparable performance to Si-doped planar heterostructures. We also report similar ISB absorption in Si- and Ge-doped nanowire heterostructures indicating that the choice of dopant is not an intrinsic barrier for observing ISB phenomena. The spectral shift of the ISB absorption as a function of the doping concentration due to many body effects confirms that Si and Ge efficiently dope GaN/AlN nanowire heterostructures.
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We present a set of experimental results showing a combination of various effects, that is, surface recombination velocity, surface charge traps, strain, and structural defects, that govern the carrier dynamics of self-catalyzed GaAs/AlGaAs core-shell nanowires (NWs) grown on a Si(111) substrate by molecular beam epitaxy. Time-resolved photoluminescence of NW ensemble and spatially resolved cathodoluminescence of single NWs reveal that emission intensity, decay time, and carrier diffusion length of the GaAs NW core strongly depend on the AlGaAs shell thickness but in a nonmonotonic fashion. Although 7 nm AlGaAs shell can efficiently suppress the surface recombination velocity of the GaAs NW core, the influence of the surface charge traps and the strain between the core and the shell that redshift the luminescence of the GaAs NW core remain observable in the whole range of the shell thickness. In addition, the band bending effect induced by the surface charge traps can alter the scattering of the excess carriers inside the GaAs NW core at the core/shell interface. If the AlGaAs shell thickness is larger than 50 nm, the luminescence efficiency of the GaAs NW cores deteriorates, ascribed to defect formation inside the AlGaAs shell evidenced by transmission electron microscopy.
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BACKGROUND: A minority of early breast cancer (EBC) patients treated with adjuvant or neoadjuvant chemotherapy have sufficient baseline vitamin D (vitD) level. This randomized phase III study assessed the safety and efficacy of a tailored, high-dose, oral vitD supplementation in restoring a normal 25-hydroxy vitD (25OHD) level in this population. PATIENTS AND METHODS: Participants received a 6-month conventional (C) vitD and calcium supplementation or a 6-month high-dose oral vitD regimen tailored on the deficiency (T) and a conventional calcium supplementation. The primary end point was the 6-month percentage of 25OHD serum level normalization. RESULTS: A total of 215 patients including 197 patients with vitD deficiency were recruited, and 195 patients were randomized (T, 100; C, 95). Compliance to the daily oral supplementation was 68.4% and 67% in the C and T arms, respectively. Discontinuous high-dose vitD compliance appeared higher in the T arm (77%). At 6 months, more patients presented with a normalized vitD level in the T arm (30% versus 12.6%; P = 0.003). Supplementation was well tolerated, and no significant difference in the treatment-related toxicity between the two arms was reported. Fifty-two patients without vitD normalization from the C arm switched to the T arm after 6 months. At 12 months, 44% of these patients achieved vitD normalization. CONCLUSION: A tailored high-dose oral vitD supplementation safely allows a higher percentage of the serum 25OHD level normalization compared with a conventional regimen in chemotherapy-treated EBC patients. As compliance to a daily oral supplementation remains poor in this setting, an adaptation of the treatment schedule is warranted. CLINICAL TRIAL NUMBER: NCT01480869.
Assuntos
Neoplasias da Mama/dietoterapia , Suplementos Nutricionais , Deficiência de Vitamina D/dietoterapia , Vitamina D/administração & dosagem , Adulto , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Qualidade de Vida , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/patologiaRESUMO
The existence of intrinsic carrier interface states in heterostructures with no common atom at the interface (such as ZnSe/BeTe) is shown experimentally by ellipsometry and photoluminescence spectroscopy. These states are located on interfaces and lie inside the effective bandgap of the structure; they are characterized by a high density and a long lifetime. A tight binding model confirms theoretically the existence of these states in ZnSe/BeTe heterostructures for a ZnTe-type interface, in contrast to the case of the BeSe-type interface for which they do not exist.
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We report near-field scanning optical imaging with an active tip made of a single fluorescent CdSe nanocrystal attached at the apex of an optical tip. Although the images are acquired only partially because of the random blinking of the semiconductor particle, our work validates the use of such tips in ultra-high spatial resolution optical microscopy.
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Evaluation of tumour size modifications in response to treatment is a critical issue in the management of advanced malignancies. In 1981, the World Health Organization (WHO) established guidelines for tumour response assessment. These WHO1981 criteria were recently simplified in a revised version, named RECIST (Response Evaluation Criteria in Solid Tumours), which uses unidimensional instead of bidimensional measurements, a reduced number of measured lesions, withdrawal of the progression criteria based on isolated increase of a single lesion, and different shrinkage threshold for definitions of tumour response and progression. In order to validate these new guidelines, we have compared results obtained with both classifications in a prospective series of 91 patients receiving chemotherapy for metastatic colorectal cancer. Data from iterative tomographic measurements were fully recorded and reviewed by an expert panel. The overall response and progression rates according to the WHO1981 criteria were 19% and 58%, respectively. Using RECIST criteria, 16 patients were reclassified in a more favourable subgroup, the overall response rate being 28% and the progression rate 45% (non-weighted kappa concordance test 0.72). When isolated increase of a single measurable lesion is not taken into account for progression with the WHO1981 criteria, only 7 patients were reclassified and the kappa test was satisfying, i.e. > or =0.75, for the whole population as well as for each of the responding and progressive subgroups. Since it provides concordant results with a simplified method, the use of RECIST criteria is recommended for evaluation of treatment efficacy in clinical trials and routine practice.
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Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/patologia , Guias de Prática Clínica como Assunto , Adenocarcinoma/patologia , Idoso , Progressão da Doença , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
AIMS: Computed tomography (CT) is the reference technique for evaluating response to chemotherapy. The potential helpfulness of tumour markers is debated. MATERIALS AND METHODS: From March 1997 to January 1999, 91 consecutive patients receiving chemotherapy for metastatic colorectal carcinoma underwent whole-body spiral CT, estimates of anti-carcinoembryonic antigen (CEA) and CA19-9 every 8 weeks. RESULTS: CEA and CA19-9 levels were above normal in 78 (85.7%) and 61 (67.5%) patients, respectively. Tumour response evaluation according to the RECIST criteria was obtained at 8-week evaluation in 83 (91%) patients. The positive predictive values (PPV) for response of a decrease of the marker levels were 53.8 for CEA and 41.7 for CA19-9 using a 30% decrease threshold, and 60/52.2, respectively, using a 50% decrease threshold. Meaningful PPV values (> 90%) for progression of an increase of the marker levels were only obtained using the 200% increase threshold for CEA alone or a combination of CEA and CA 19-9. A 100% CEA increase between baseline and the 8-week evaluation was correlated to overall survival (P = 0.0023). The need for a radiological confirmation of tumour progression could be avoided by the systematic dosage of tumour markers at baseline and after 8 weeks of treatment only in a sub-population of 13% of the patients with a 200% increase of CEA or CA 19-9 at 8 weeks. CONCLUSIONS: CEA, CA 19-9, or both should be used with caution for tumour response evaluation to chemotherapy in addition to CT in metastatic colorectal carcinoma.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Antígeno CA-19-9/análise , Antígeno Carcinoembrionário/análise , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Idoso , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Análise de Sobrevida , Tomografia Computadorizada Espiral , Resultado do TratamentoRESUMO
It is a randomised cross-over multicenter study comparing the efficacy and the tolerance of granisetron (Gra) 1 mg and ondansetron (Ond) 8 mg, oral, given during two consecutive cycles to 188 naive patients scheduled to receive a moderately emetogenic chemotherapy. The antiemetic treatment is given one day per course, 1 hour before chemotherapy and the second administration from 8 to 12 hours after the beginning, during each of the two cycles; alternatively according to the randomisation. Five criteria are assessed; nausea (ordinal and visual analogic scales), emeric episodes (vomiting orland retching), complete response (minor or no nausea, no emetic episode and no rescue treatment), patient preference and tolerance. The intent to treat analysis showed no significant difference at cycle 1 between Gra and Ond; at cycle 2, there is no significant difference in the number of emetic episodes; for the prevention of nausea, the ordinal scale shows a significant difference (p = 0.028 in favour of Gra at day 1 (D1) but not from D2 to D5. Gra induced more complete response than Ond at D1 (p = 0.028), but not from D2 to D5. The cross-over study did not show any period or order effect, whereas a treatment effect on Ond was significant in favour of Gra (p = 0.01). There is no significant patients preference in favour of Gra or Ond. In conclusion, Gra was more efficient in preventing nausea and obtaining complete response on the first day of treatment, significantly at the second cycle. Both Gra and Ond had a good antiemetic activity for moderately emetogenic chemotherapy with complete response rates always over 50% on day 1; delayed emesis remain less weli controlled.
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Antieméticos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Granisetron/uso terapêutico , Náusea/prevenção & controle , Ondansetron/uso terapêutico , Vômito/prevenção & controle , Adulto , Bleomicina/efeitos adversos , Estudos Cross-Over , Ciclofosfamida/efeitos adversos , Doxorrubicina/efeitos adversos , Feminino , Humanos , Masculino , Metotrexato/efeitos adversos , Náusea/induzido quimicamente , Prednisona/efeitos adversos , Vindesina/efeitos adversos , Vômito/induzido quimicamenteRESUMO
BACKGROUND: Biweekly schedule of capecitabine combined with irinotecan (XELIRI), consecutively with irinotecan and oxaliplatin (XELIRINOX), was evaluated in patients with metastatic cancer from any solid tumors. PATIENTS AND METHODS: In this two-step phase I trial, seventeen and eleven patients were enrolled in the XELIRI and XELIRINOX stages, respectively. RESULTS: In XELIRI, a total of 136 chemotherapy cycles were administered with a median number of 8 cycles per patient (2-16). Main dose-limiting toxicities (DLT) were grade 3-4 neutropenia, with one toxicity-related death. Maximum tolerated dose (MTD) for capecitabine combined with 180 mg/m(2) of irinotecan was 3,500 mg/m(2)/day. In XELIRINOX, capecitabine starting dose was 2,500 mg/m(2)/day. Fifty-eight chemotherapy cycles were administered with a median of 4 cycles per patient (1-16). DLT included 3 grade 4 neutropenia, associated with 1 grade 3 diarrhea, and 1 grade 4 pneumopathy leading to patient death. MTD for capecitabine with 180 mg/m(2) of irinotecan and 85 mg/m(2) of oxaliplatin was 3,000 mg/m(2)/day. The recommended doses for capecitabine were 3,000 and 2,500 mg/m(2)/day D1-D7 in combination with 180 mg/m(2) of irinotecan in XELIRI, plus 85 mg/m(2) of oxaliplatin in XELIRINOX (D1 = D14), respectively. CONCLUSION: XELIRI and XELIRINOX regimens are feasible and warrant further investigation in combination with targeted therapy in metastatic colorectal cancer patients.