Adherent diamond coatings on cemented tungsten carbide substrates with new Fe/Ni/Co binder phase

WC-Co hard metals continue to gain importance for cutting, mining and chipless forming tools. Cobalt metal currently dominates the market as a binder because of its unique properties. However, the use of cobalt as a binder has several drawbacks related to its hexagonal close-packed structure and market price fluctuations. These issues pushed the development of pre-alloyed binder powders which contain less than 40 wt.% cobalt. In this paper we first report the results of extensive investigations of WC-Fe/Ni/Co hard metal sintering, surface pretreating and deposition of adherent diamond films by using an industrial hot filament chemical vapour deposition (HFCVD) reactor. In particular, CVD diamond was deposited onto WC-Fe/Ni/Co grades which exhibited the best mechanical properties. Prior to deposition, the substrates were submitted to surface roughening by Murakami's etching and to surface binder removal by aqua regia. The adhesion was evaluated by Rockwell indentation tests (20, 40, 60 and 100 kg) conducted with a Brale indenter and compared to the adhesion of diamond films grown onto Co-cemented tungsten carbide substrates, which were submitted to similar etching pretreatments and identical deposition conditions. The results showed that diamond films on medium-grained WC-6 wt.% Fe/Ni/Co substrates exhibited good adhesion levels, comparable to those obtained for HFCVD diamond on Co-cemented carbides with similar microstructure

Variaciones en la morfología de las hojas y brotes de yema de Ulmus minor en Italia y Francia

More than 40 Ulmus minor clones were characterised on the basis of 10 foliar morphological traits and budburst phenology in two successive years. Ramets, 4- and 5-years-old, were obtained by means of self-rooted cuttings from elms located in northern, central and southern Italy and in France. Measurements were taken in an open field in the vicinity of Florence (Italy). The morphological traits were found not to be appropriate for describing the variability between clones of different origins, even if some of these traits indicated a xeric adaptation in clones originating from southern Italy. On the contrary, the phenological traits were valid describers of the origin of the clones. Indeed, the southern-Italian clones flushed earlier than the others, while the French clones were more delated. A comparison of the results of the two years showed that the chilling requirements on the trial site were not satisfied. The actual state of knowledge regarding dormancy in the Ulmus genus does not enable to speculate further on the results of this research. Morphological characters seem to show a greater phenotypic plasticity with respect to phenological traits.Más de 40 clones de Ulmus minor han sido caracterizados basándose en 10 características morfológicas foliares y en la fenología de la apertura de yemas foliares en dos años sucesivos. Los ramets, de 4 y 5 años de edad, se obtuvieron por medio de estaquillas procedentes de olmos localizados en Italia septentrional, central y meridional, y en Francia. Las mediciones se realizaron al aire libre en las cercanías de Florencia (Italia). Se encontró que las características morfológicas no fueron adecuadas para describir la variabilidad entre clones de distintos orígenes, incluso cuando estas características indicaban, en clones del sur de Italia, una adaptación a condiciones xéricas. Por el contrario, las características fenológicas sirvieron como descriptores válidos del origen de los clones. De hecho, los clones de Italia meridional brotaron antes que los otros, mientras que los clones franceses fueron más tardíos. La comparación de los resultados de ambos años mostró que los requerimientos de frío no fueron satisfechos en la parcela de ensayo. El actual estado de conocimiento en relación con la quiescencia en el género Ulmus no permite realizar conjeturas con los resultados de este estudio. Las características morfológicas parecen mostrar una mayor plasticidad fenotípica que las características fenológicas

Design-based mapping for finite populations of marked points

The estimation of marks for a finite population of points scattered onto a study region is considered when a sample of these points is selected by a probabilistic sampling scheme. At each point, the mark is estimated by means of an inverse distance weighting interpolator. The design-based asymptotic properties of the resulting maps are derived when the study area remains fixed, a sequence of nested populations with increasing size is considered and samples of increasing size are selected. Conditions ensuring design-based asymptotic unbiasedness and consistency are given. They essentially require that marks are the values of a pointwise or uniformly continuous deterministic function, the enlargement of the populations is rather regular and the sequence of sampling designs ensures an asymptotic spatial balance. A computationally simple mean squared error estimator is proposed. A simulation study is performed to assess the theoretical results on artificial populations. Finally, an application for mapping the values of the height of trees in a forest stand located in North Italy is reported

Secondary malignancies after treatment for indolent non-Hodgkin's lymphoma: a 16-year follow-up study.

Relatively little information is available on the incidence of secondary cancer in non-Hodgkin's lymphoma. The aim of this long-term follow-up study was to determine the incidence, the time free of second tumors, and risk factors for developing secondary cancer in a homogeneous group of patients with non-Hodgkin's lymphoma. DESIGN AND METHODS: We evaluated a total of 563 patients with indolent non-Hodgkin's lymphoma enrolled in Gruppo Italiano Studio Linfomi trials from 1988 to 2003. RESULTS: After a median follow-up of 62 months, 39 patients (6.9%) developed secondary cancer: 12 myelodysplastic syndromes/acute myeloid leukemia, and 27 solid tumors. The overall standardized incidence ratio of secondary malignancy in patients with non-Hodgkin's lymphoma was higher than the risk of malignancy in the general population. The standardized incidence ratio was elevated in male patients and in patients under 65 years old at first treatment. Overall, the cumulative incidence of secondary cancer at 12 years was 10.5%, after correction in a competing-risk model. Univariate and multivariate Cox regression analyses showed that older age at the time of diagnosis, male sex, and fludarabine-containing therapy had significant negative impacts on the time free of second tumors. CONCLUSIONS: We have identified subgroups of non-Hodgkin's lymphoma patients with increased standardized incidence ratios of secondary malignancy and variables that have a negative impact on the time free of second tumors. This information could help physicians to select the most appropriate treatments. Finally, taking into account the possible occurrence of secondary neoplasia, long-term monitoring must be considered

Statistical inference on the h-index with an application to top-scientist performance

Despite the huge amount of literature on h-index, few papers have been devoted to the statistical analysis of h-index when a probabilistic distribution is assumed for citation counts. The present contribution relies on showing the available inferential techniques, by providing the details for proper point and set estimation of the theoretical h-index. Moreover, some issues on simultaneous inference - aimed to produce suitable scholar comparisons - are carried out. Finally, the analysis of the citation dataset for the Nobel Laureates (in the last five years) and for the Fields medallists (from 2002 onward) is proposed.Comment: 14 pages, 3 table