Cross-calibration of S-NPP VIIRS moderate resolution reflective solar bands against MODIS Aqua over dark water scenes.

The Visible Infrared Imaging Radiometer Suite (VIIRS) is being used to continue the record of Earth Science observations and data products produced routinely from National Aeronautics and Space Administration (NASA) Moderate Resolution Imaging Spectroradiometer (MODIS) measurements. However, the absolute calibration of VIIRS's reflected solar bands is thought to be biased, leading to offsets in derived data products such as aerosol optical depth (AOD) as compared to when similar algorithms are applied to different sensors. This study presents a cross-calibration of these VIIRS bands against MODIS Aqua over dark water scenes, finding corrections to the NASA VIIRS Level 1 (version 2) reflectances between approximately +1 % and -7 % (dependent on band) are needed to bring the two into alignment (after accounting for expected differences resulting from different band spectral response functions), and indications of relative trending of up to ^0.35 % per year in some bands. The derived calibration gain corrections are also applied to the VIIRS reflectance and then used in an AOD retrieval, and are shown to decrease the bias and total error in AOD across the midvisible spectral region compared to the standard VIIRS NASA reflectance calibration. The resulting AOD bias characteristics are similar to those of NASA MODIS AOD data products, which is encouraging in terms of multisensor data continuity.

Cirrus cloud optical and microphysical property retrievals from eMAS during SEAC4RS using bi-spectral reflectance measurements within the 1.88 µm water vapor absorption band.

Previous bi-spectral imager retrievals of cloud optical thickness (COT) and effective particle radius (CER) based on the Nakajima and King (1990) approach, such as those of the operational MODIS cloud optical property retrieval product (MOD06), have typically paired a non-absorbing visible or near-infrared wavelength, sensitive to COT, with an absorbing shortwave or midwave infrared wavelength sensitive to CER. However, in practice it is only necessary to select two spectral channels that exhibit a strong contrast in cloud particle absorption. Here it is shown, using eMAS observations obtained during NASA's SEAC4RS field campaign, that selecting two absorbing wavelength channels within the broader 1.88 µm water vapor absorption band, namely the 1.83 and 1.93 µm channels that have sufficient differences in ice crystal single scattering albedo, can yield COT and CER retrievals for thin to moderately thick single-layer cirrus that are reasonably consistent with other solar and IR imager-based and lidar-based retrievals. A distinct advantage of this channel selection for cirrus cloud retrievals is that the below-cloud water vapor absorption minimizes the surface contribution to measured cloudy TOA reflectance, in particular compared to the solar window channels used in heritage retrievals such as MOD06. This reduces retrieval uncertainty resulting from errors in the surface reflectance assumption, as well as reduces the frequency of retrieval failures for thin cirrus clouds.

[Proposal for a data collection system for colposcopy services]. / Proposta di un sistema di archiviazione dati per un servizio di colposcopia.

A computerized system for colpocytologic data collection and filing, is presented. A descriptive and easy to elaborate recording of anamnestical data and examination findings is achieved using two correlated files. Step by step filing is obtained by multichoice scheme which progressively appears on the screen.

Feto-placental haemodynamics in growth retardation: a pulsed Doppler study.

69 singleton pregnancies, with a diagnosis of intra-uterine growth retardation (IUGR) at ultrasound, were followed until delivery by pulsed Doppler evaluations in fetal thoracic descending aorta (DA) and umbilical artery (UA). Three haemodynamic groups were described according to flow characteristics expressed as the pulsatility index (PI) of the vessel under study. In each group the relative incidence of fetal distress, diagnosed according to CTG monitoring, was evaluated. Fetal distress occurred in 75% of the cases with a raised PI both in DA and UA, in 40% of the cases with a raised PI only in DA and in 21% of the cases with 'normal' PI values in both vessels. It can be said that Doppler flow measurements can be useful in defining the actual haemodynamic situation of the fetus with possible clarifications concerning its 'stressed' or 'distressed' condition and residual capacities to substain hypoxia.

A clinical and epidemiological study of 245 postmenopausal metrorrhagia patients.

The authors report the incidence of endometrial adenocarcinoma and atypical hyperplasia in 245 women who had undergone uterine curettage for post-menopausal bleeding. In 4 cases a stenosis of the cervix precluded the curettage. Of the remaining 241 patients, 71.3% had negative histology; in 24.4% histology was compatible with adenocarcinoma or atypical endometrial hyperplasia; in a third group of 10 patients a different type of gynecological neoplasia was diagnosed. Obese, nulliparous women were more significantly affected by endometrial adenocarcinoma. The highest incidence was noted among women over 60 years of age. The authors describe some epidemiological and clinical characteristics of the population under study.