Polen atmosférico en San Sebastián: 1983, 1984, 1985. I. Polen total y Gramíneas

Con un Captador volumétrico Burkard se ha estudiado el polen atmosférico en San Sebastián desde el 21 de marzo de 1983 al 30 de septiembre de 1985. Se han confeccionado unos gráficos de concentraciones medias semanales de pólenes totales y de Gramíneas como contribución a la realización del Mapa Polínico de España

Thermodynamics of the incommensurate state in Rb_2WO_4: on the Lifshitz point in A`A``BX_4 compounds

We consider the evolution of the phase transition from the parent hexagonal phase $P6_{3}/mmc$ to the orthorhombic phase $Pmcn$ that occurs in several compounds of $A'A''BX_{4}$ family as a function of the hcp lattice parameter $c/a$. For compounds of $K_{2}SO_{4}$ type with $c/a$ larger than the threshold value 1.26 the direct first-order transition $Pmcn-P6_{3}/mmc$ is characterized by the large entropy jump $Rln2$. For compounds $Rb_{2}WO_{4}$, $K_{2}MoO_{4}$, $K_{2}WO_{4}$ with $c/a<1.26$ this transition occurs via an intermediate incommensurate $(Inc)$ phase. DSC measurements were performed in $Rb_{2}WO_{4}$ to characterize the thermodynamics of the $Pmcn-Inc-P6_{3}/mmc$ transitions. It was found that both transitions are again of the first order with entropy jumps $0.2Rln2 and$0.3Rln2$. Therefore, at$c/a ~ 1.26$the$A'A''BX_{4}$compounds reveal an unusual Lifshitz point where three first order transition lines meet. We propose the coupling of crystal elasticity with$BX_{4}$ tetrahedra orientation as a possible source of the transitions discontinuity.Comment: 13 pages,1 Postscript figure. Submitted as Brief Report to Phys. Rev. B, this paper reports a new work in Theory and Experiment, directed to Structural Phase Transition

Final results from the PERUSE study of first-line pertuzumab plus trastuzumab plus a taxane for HER2-positive locally recurrent or metastatic breast cancer, with a multivariable approach to guide prognostication

Background: The phase III CLinical Evaluation Of Pertuzumab And TRAstuzumab (CLEOPATRA) trial established the combination of pertuzumab, trastuzumab and docetaxel as standard first-line therapy for human epidermal growth factor receptor 2 (HER2)-positive locally recurrent/metastatic breast cancer (LR/mBC). The multicentre single-arm PERtUzumab global SafEty (PERUSE) study assessed the safety and efficacy of pertuzumab and trastuzumab combined with investigator-selected taxane in this setting. Patients and methods: Eligible patients with inoperable HER2-positive LR/mBC and no prior systemic therapy for LR/mBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab and pertuzumab until disease progression or unacceptable toxicity. The primary endpoint was safety. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). Prespecified subgroup analyses included subgroups according to taxane, hormone receptor (HR) status and prior trastuzumab. Exploratory univariable analyses identified potential prognostic factors; those that remained significant in multivariable analysis were used to analyse PFS and OS in subgroups with all, some or none of these factors. Results: Of 1436 treated patients, 588 (41%) initially received paclitaxel and 918 (64%) had HR-positive disease. The most common grade 653 adverse events were neutropenia (10%, mainly with docetaxel) and diarrhoea (8%). At the final analysis (median follow-up: 5.7 years), median PFS was 20.7 [95% confidence interval (CI) 18.9-23.1] months overall and was similar irrespective of HR status or taxane. Median OS was 65.3 (95% CI 60.9-70.9) months overall. OS was similar regardless of taxane backbone but was more favourable in patients with HR-positive than HR-negative LR/mBC. In exploratory analyses, trastuzumab-pretreated patients with visceral disease had the shortest median PFS (13.1 months) and OS (46.3 months). Conclusions: Mature results from PERUSE show a safety and efficacy profile consistent with results from CLEOPATRA and median OS exceeding 5 years. Results suggest that paclitaxel is a valid alternative to docetaxel as backbone chemotherapy. Exploratory analyses suggest risk factors that could guide future trial design

Preliminary safety and efficacy of first-line pertuzumab combined with trastuzumab and taxane therapy for HER2-positive locally recurrent or metastatic breast cancer (PERUSE).

BACKGROUND: Pertuzumab combined with trastuzumab and docetaxel is the standard first-line therapy for HER2-positive metastatic breast cancer, based on results from the phase III CLEOPATRA trial. PERUSE was designed to assess the safety and efficacy of investigator-selected taxane with pertuzumab and trastuzumab in this setting. PATIENTS AND METHODS: In the ongoing multicentre single-arm phase IIIb PERUSE study, patients with inoperable HER2-positive advanced breast cancer (locally recurrent/metastatic) (LR/MBC) and no prior systemic therapy for LR/MBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab [8\u2009mg/kg loading dose, then 6\u2009mg/kg every 3\u2009weeks (q3w)] and pertuzumab (840\u2009mg loading dose, then 420\u2009mg q3w) until disease progression or unacceptable toxicity. The primary end point was safety. Secondary end points included overall response rate (ORR) and progression-free survival (PFS). RESULTS: Overall, 1436 patients received at least one treatment dose (initially docetaxel in 775 patients, paclitaxel in 589, nab-paclitaxel in 65; 7 discontinued before starting taxane). Median age was 54\u2009years; 29% had received prior trastuzumab. Median treatment duration was 16\u2009months for pertuzumab and trastuzumab and 4\u2009months for taxane. Compared with docetaxel-containing therapy, paclitaxel-containing therapy was associated with more neuropathy (all-grade peripheral neuropathy 31% versus 16%) but less febrile neutropenia (1% versus 11%) and mucositis (14% versus 25%). At this preliminary analysis (52 months' median follow-up), median PFS was 20.6 [95% confidence interval (CI) 18.9-22.7] months overall (19.6, 23.0 and 18.1\u2009months with docetaxel, paclitaxel and nab-paclitaxel, respectively). ORR was 80% (95% CI 78%-82%) overall (docetaxel 79%, paclitaxel 83%, nab-paclitaxel 77%). CONCLUSIONS: Preliminary findings from PERUSE suggest that the safety and efficacy of first-line pertuzumab, trastuzumab and taxane for HER2-positive LR/MBC are consistent with results from CLEOPATRA. Paclitaxel appears to be a valid alternative taxane backbone to docetaxel, offering similar PFS and ORR with a predictable safety profile. CLINICALTRIALS.GOV: NCT01572038

The ferroelectric phase transition in (CH3_3)4_4NCdBr3_3 (TMCB) studied by means of group theory, Raman scattering and calorimetry

A group theoretical investigation of the improper ferroelectric phase transition occurring in crystals of (CH$_3$)$_4$NCdBr$_3$ (TMCB) at $T_c \approx 160$ K is developed, on the basis of previous structural eterminations of both paraelectric (P6$_3$/m, Z = 2) and ferroelectric (P6$_1$(P6$_5$), Z = 6) phases ; in particular, the pseudo-spin variables attached to the reorientations of the (CH$_3$)$_4$N$^{+}$ (TMA) groups, acting as order-parameters, are considered. The Raman spectra indicate that the transition is undoubtedly of order-disorder type, as a result of reorientations of the TMA groups. This is further confirmed by the large transition entropy as measured by calorimetry ($\Delta S = 2.17 \pm 0.20 R$). The experimental results are compared with classical Landau theory predictions.La transition de phase ferroélectrique impropre se produisant dans les cristaux de (CH$_3$)$_4$NCdBr$_3$ (TMCB) à $T_c \approx 160$ K est étudiée à l'aide de la théorie des groupes, à partir des données structurales établies antérieurement à la fois pour la phase paraélectrique (P6$_3$/m, Z = 2) et pour la phase ferroélectrique (P6$_1$(P6$_5$), Z = 6) ; en particulier, les variables de pseudospin décrivant les réorientations des groupes (CH$_3$)$_4$N$^+$ (TMA) agissant comme paramètres d'ordre sont déterminées. Les spectres Raman indiquent que cette transition est sans aucun doute du type ordre-désordre, liée aux réorientations des groupes TMA, ce qui de plus est confirmé par l'importante entropie de transition déterminée par calorimétrie ($\Delta S = 2,17 \pm 0,20 R$). Les résultats expérimentaux sont comparés avec les prévisions de la théorie de Landau

Intrinsic kinetic effects during martensitic transformations

In this paper, we present a study by AC calorimetry on the thermoelastic martensitic transformation in a Cu-Al-Ni shape memory alloy, both under quasi-isothermal conditions and by using a dynamical method. Whereas internal friction measurements have shown that the martensitic transformation behaviour exhibits a strong dependence on the rate of change of temperature in both cooling and heating, calorimetric measurements using DSC do not usually show this dependence. Therefore, it is usually argued that the internal friction results are linked to the measurement technique and not to the martensitic transformation itself. However, our AC calorimetry measurements also suggest that the martensitic transformation exhibits some intrinsic kinetic effects dependent on the rate of change of temperature