458 research outputs found
COROLOGIA, AUTOECOLOGIA E SINECOLOGIA DI ANDROSACE BREVIS (HEGETSCHW.) CES
Androsace brevis is a protected species according to Regional Law 10/2008, included in the National Red List because of its status as an endemic and as a rare species in its distribution range. It is a high altitude, light-demanding cushion plant, with an early flowering period (end of May to the start of June), present above 2000 m asl on rocky ridges exposed to strong winds, on prealpine terrigenous substrates. The distribution range of A. brevis is not yet well defined, and is peculiar compared to the distribution range of other Lombardy endemic species; it consists of two large discontinuous populations separated by Lake Como, on the Western Orobian Alps and the Lugano Prealps and a small portion of the Lepontine Alps, in addition to more disjointed populations in the Rhaetian Alps. The University of Milan has started a research project that aims to define in detail the distribution range of this species (and the causes of this distribution), its distribution, autoecology and sinecology
Vegetation outlines of two active rock glaciers with contrasting lithology
Rock glaciers are periglacial landforms consisting of coarse debris with interstitial ice or ice core, characterized by creeping due to ice deformation.
These landforms are drawing the attention of plant ecologist as harsh habitats and potential refugia in the global change context. Our aim was to
describe the vegetation outlines of two active rock glaciers of the Ortles-Cevedale Massif (Central Italian Alps) on different substrates (silicate and
carbonate) and compare them with the neighboring stable slopes and scree slopes. Two hypotheses were tested: 1) rock glaciers differ from the surrounding
landforms for the presence of cold-adapted plant communities; 2) rock glacier plant communities indicate similar microclimatic conditions
in spite of the contrasting lithology. Data were collected by phytosociological method performing 80 relev\ue9s of 25 m\ub2. Plant communities were
compared by a cluster analysis based on the presence/absence species matrix and species relative frequencies for each landform were calculated. The
cluster analysis separated first for all the two sites; afterwards, the landforms were differently discerned each other depending on the site. Despite
the remarkable floristic differences due to the substrate, the vegetation of both rock glaciers suggest a general adjustment to cold-moist microclimate
and long-lasting snow cover, differentiating more or less evidently from the adjacent scree slopes and enhancing the survival of nival entities at the
elevation of alpine grasslands
CMB Polarization can constrain cosmology better than CMB temperature
We demonstrate that for a cosmic variance limited experiment, CMB E
polarization alone places stronger constraints on cosmological parameters than
CMB temperature. For example, we show that EE can constrain parameters better
than TT by up to a factor 2.8 when a multipole range of l=30-2500 is
considered. We expose the physical effects at play behind this remarkable
result and study how it depends on the multipole range included in the
analysis. In most relevant cases, TE or EE surpass the TT based cosmological
constraints. This result is important as the small scale astrophysical
foregrounds are expected to have a much reduced impact on polarization, thus
opening the possibility of building cleaner and more stringent constraints of
the LCDM model. This is relevant specially for proposed future CMB satellite
missions, such as CORE or PRISM, that are designed to be cosmic variance
limited in polarization till very large multipoles. We perform the same
analysis for a Planck-like experiment, and conclude that even in this case TE
alone should determine the constraint on better than TT by 15%,
while determining , and with comparable accuracy.
Finally, we explore a few classical extensions of the LCDM model and show again
that CMB polarization alone provides more stringent constraints than CMB
temperature in case of a cosmic variance limited experiment.Comment: 14 pages, 16 figure
Chemotherapy-related damage to ovarian reserve in childhood cancer survivors : interpreting the evidence
Chemotherapy during childhood damages ovarian reserve and can affect future fertility. However, recent large epidemiological studies showed that the detrimental impact on fertility is less severe if women seek for pregnancy at a younger age. To explain this observation, we hypothesize that the detrimental effects of previous chemotherapy on the ovarian reserve may be attenuated in young adults for two main reasons. Firstly, recent evidence showed that the amount of ovarian reserve is not a critical factor for effective natural conceptions. Provided that the residual ovarian reserve allows regular ovulatory cycles, the chances of pregnancy are similar in women with intact or reduced ovarian reserve. Secondly, ovarian reserve depletion appears to be a phenomenon that is inversely related to the residual ovarian reserve rather than to age. From a mathematical perspective, this kind of regulation intrinsically attenuates the effects of an early loss of a significant amount of primordial follicles. In conclusion, the detrimental effects of chemotherapy on natural fertility may be less severe if women with a history of chemotherapy during childhood seek for pregnancy early. This information should be part of the counseling
Narrow Band Imaging and High Definition Television in endoscopic evaluation of upper aero-digestive tract cancer.
Narrow band imaging and high definition television are recent innovations in upper aero-digestive tract endoscopy. Aim of this prospective,
non-randomized, unblinded study was to establish the diagnostic advantage of these procedures in the evaluation of squamous cell cancer
arising from various upper aero-digestive tract sites. Between April 2007 and January 2010, 444 patients affected by upper aero-digestive
tract squamous cell cancer, or previously treated for it, were evaluated by white light and narrow band imaging ± high definition television
endoscopy, both in the pre-/intra-operative setting and during follow-up. Tumour resection was performed taking into account narrow band
imaging and high definition television information to obtain histopathologic confirmation of their validity. Endoscopic and pathologic data
were subsequently matched to obtain sensitivity, specificity, positive, negative predictive values, and accuracy. Overall, 110 (25%) patients
showed adjunctive findings by narrow band imaging ± high definition television when compared to standard white light endoscopy. Of
these patients, 98 (89%) received histopatological confirmation. The sensitivity, specificity, positive, negative predictive values, and accuracy
for white light-high definition television were 41%, 92%, 87%, 82%, and 67%, for narrow band imaging alone 75%, 87%, 87%,
74%, and 80%, and for narrow band imaging-high definition television 97%, 84%, 88%, 96%, and 92%. The highest diagnostic gain was
observed in the oral cavity and oropharynx (25%). Narrow band imaging and high definition television were of value in the definition of
superficial tumour extension, and in the detection of synchronous lesions in the pre-/intra-operative settings. These technologies also played
an important role during post-treatment surveillance for early detection of persistences, recurrences, and metachronous tumours
Quantitative analysis of videokymography in normal and pathological vocal folds: a preliminari study.
Videokymography (VKG) captures high-speed
images of the vocal folds independently of the periodicity
of the acoustic signal. The aim of this study was to preliminarily
assess a software package that can objectively
measure specific parameters of vocal fold vibration. From
August 2009 until December 2010, we prospectively
evaluated 40 subjects (Group A, 18 normal subjects;
Group B, 14 patients with benign lesions of the middle
third of the vocal fold, such as polyps and cysts; Group C, 8
patients treated by endoscopic excision of vocal fold
benign lesions) by videoendoscopy, videolaryngostroboscopy,
and VKG. A VKG camera was coupled to a 70
telescope and video was recorded during phonation. Images
were objectively analyzed by a post-processing software
tool (VKG-Analyser) with a user-friendly interface
developed by our group. Different parameters were considered,
including the ratio between the amplitude of the
vibration of one vocal fold with respect to the contralateral
(Ramp), the ratio between the period of one vocal fold
vibration and the opposite one (Rper), and the ratio between
the duration of the open and closed phase within a glottal
cycle (Roc). Mean values for Ramp, Rper, and Roc in Group A
were 1.05, 1.04, and 1.35, respectively; in Group B were
1.63, 0.92, and 0.97, respectively; and in Group C were
1.13, 0.91, and 1.85, respectively. Quantitative analysis of
videokymograms by the herein presented tool, named VKG-Analyser, is useful for objective evaluation of the
vibratory pattern in normal and pathologic vocal folds.
Important future developments of this tool for the study of
both physiologic and pathologic patterns of vocal fold
vibration can be expected
Narrow Band Imaging and High Definition Television in the endoscopic evaluation of upper aero-digestive tract cancer
Narrow band imaging and high definition television are recent innovations in upper aero-digestive tract endoscopy. Aim of this prospective,
non-randomized, unblinded study was to establish the diagnostic advantage of these procedures in the evaluation of squamous cell cancer
arising from various upper aero-digestive tract sites. Between April 2007 and January 2010, 444 patients affected by upper aero-digestive
tract squamous cell cancer, or previously treated for it, were evaluated by white light and narrow band imaging ± high definition television
endoscopy, both in the pre-/intra-operative setting and during follow-up. Tumour resection was performed taking into account narrow band
imaging and high definition television information to obtain histopathologic confirmation of their validity. Endoscopic and pathologic data
were subsequently matched to obtain sensitivity, specificity, positive, negative predictive values, and accuracy. Overall, 110 (25%) patients
showed adjunctive findings by narrow band imaging ± high definition television when compared to standard white light endoscopy. Of
these patients, 98 (89%) received histopatological confirmation. The sensitivity, specificity, positive, negative predictive values, and accuracy
for white light-high definition television were 41%, 92%, 87%, 82%, and 67%, for narrow band imaging alone 75%, 87%, 87%,
74%, and 80%, and for narrow band imaging-high definition television 97%, 84%, 88%, 96%, and 92%. The highest diagnostic gain was
observed in the oral cavity and oropharynx (25%). Narrow band imaging and high definition television were of value in the definition of
superficial tumour extension, and in the detection of synchronous lesions in the pre-/intra-operative settings. These technologies also played
an important role during post-treatment surveillance for early detection of persistences, recurrences, and metachronous tumours
“Intestinal-Type” Vulvar Adenocarcinoma: A Review of the MITO Rare Tumors Group
Intestinal-type adenocarcinoma (VAIt) represents a sporadic variant of vulvar carcinoma. It appears frequently localized to epithelial glands in the vulvar region, and it probably derives from cloacal remnants persisting in the adult. We performed a systematic review of the limited cases reported in the literature, with the intent to assess the specific peculiarities of this rare neoplasia and to state consistent management recommendations. The principal histological VAIt characteristic is that it resembles mucinous colonic carcinomas. Therefore, immunohistochemical workup, with different tumor markers including CK20, CDX2, and CK7 staining, is needed. To confirm vulvar origin, a thorough diagnostic, and radiological examination is required to rule out other primary malignancies. The gold standard of treatment for VAIt is surgery, with local excision with tumor-free margins. Lymph node staging is an option advised if the tumor size is >2 cm or if lymph node metastases are suspected on imaging. On the other hand, the role of neoadjuvant therapy is still in doubt, but a good response to adjuvant chemotherapy treatments has been described in both advanced and recurrent diseases. Sometimes, VAIt behavior can be unpredictable, with relapses even after many years, so more experiences and longer follow-up periods are needed to elucidate the best therapeutic management and its long-term prognosis
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