436 research outputs found
Induction of stimulative parthenocarpy in Vitis vinifera L.
Stimulative parthenocarpy was induced in two varieties of Vitis vinifera L. Flame Tokay and Rose Muscat (local variety) out of eight varieties studied.In F l a m e T o k a y the delay or inhibition of bhe abscission of the calyptra and parthenocarpic development of the berries, was obtained with pre-bloom treatments (3 days before beginning of bloom) of 4CPA 30 ppm +Ā KGA3 30 ppm. Induction and growth ,of parthenocarpic berries was most pronounced after post-bloom sprays (7 days after the end of bloom) with BA 1500 ppm +Ā KGA3 80 ppm or 4CPA 30 ppm. A parthenocarpic development of the berries was also obtained with postbloom treatments ofĀ KGA3 at concentrations of 50 to 100 ppm. BA (Benzyladenine) alone had only a slight effect on the development of parthenocarpic berries. However, the results were surprisingly satisfactory when applied in combination with gibberellin (KGA3 80 ppm) or auxins. Treatments at bloom or after bloom with BA 800 ppm +Ā KGA3 80 ppm increased bhe number of berries and cluster weight. Applications of BA 800 ppm +Ā KGA3 80 ppm to Rose Musca t at the beginning of bloom resulted in clusters with practically all berries seedless. The artificially accelerated growth of the berries may provoke abortion of all the recently fecundated ovules and the non viability of the not fecundated ones. Clusters of the treated plants with an average of 520 flowers originated 501 parbhenocarpic berries (96%), whereas the control with an average 635 flowers per cluster gave a percentage of seeded + seedless berries of 14% only {95 berries per cluster). BA applied with auxin or gibberellin-like substances in full-bloom or after bloom produced seedless berries, which were smaller in size than the seeded berries of unsprayed clusters
Identification of pathologic features associated with āulcerative colitis-likeā Crohnās disease
AIM: To identify pathologic features associated with this āulcerative colitis (UC)-likeā subgroup of Crohnās disease (CD). METHODS: Seventeen subjects diagnosed as having UC who underwent proctocolectomy (RPC) from 2003-2007 and subsequently developed CD of the ileal pouch were identified. UC was diagnosed based on pre-operative clinical, endoscopic, and pathologic studies. Eighteen patients who underwent RPC for UC within the same time period without subsequently developing CD were randomly selected and used as controls. Pathology reports and histological slides were reviewed for a wide range of gross and microscopic pathological features, as well as extent of disease. The demographics, gross description and histopathology of the resection specimens were reviewed and compared between the two groups. RESULTS: Patients with āUC-likeā CD were on average 13 years younger than those with ātrueā UC (P < 0.01). More severe disease in the proximal involved region and active ileitis with/without architectural distortion were observed in 6 of 17 (35%) and 7 of 17 (41%) āUC-likeā CD cases, respectively, but in none of the ātrueā UC cases (P < 0.05). Active appendicitis occurred in 8 of 16 (50%) āUC-likeā CD cases but in only two (11%) ātrueā UC cases (P < 0.05). Conspicuous lamina propria neutrophils were more specific for āUC-likeā CD (76% vs 22%, P < 0.05). In addition, prominent lymphoid aggregates tended to be more common in āUC-likeā CD (P = 0.07). The ātrueā UC group contained a greater number of cases with severe activity (78% vs 47%). Therefore, the features more commonly seen in āUC-likeā CD were not due to a more severe disease process. Crohnās granulomas and transmural inflammation in non-ulcerated areas were absent in both groups. CONCLUSION: More severe disease in the proximal involved region, terminal ileum involvement, active appendicitis, and prominent lamina propria neutrophils may be morphological factors associated with āUC-likeā CD
Grey matter sublayer thickness estimation in the mouse cerebellum
The cerebellar grey matter morphology is an important feature to study neurodegenerative diseases such as Alzheimerās disease or Downās syndrome. Its volume or thickness is commonly used as a surrogate
imaging biomarker for such diseases. Most studies about grey matter thickness estimation focused on the cortex, and little attention has been drawn on the morphology of the cerebellum. Using ex vivo highresolution MRI, it is now possible to visualise the different cell layers in
the mouse cerebellum. In this work, we introduce a framework to extract the Purkinje layer within the grey matter, enabling the estimation of the thickness of the cerebellar grey matter, the granular layer and molecular
layer from gadolinium-enhanced ex vivo mouse brain MRI. Application to mouse model of Downās syndrome found reduced cortical and layer thicknesses in the transchromosomic group
Pulsar acceleration by asymmetric emission of sterile neutrinos
A convincing explanation for the observed pulsar large peculiar velocities is
still missing. We argue that any viable particle physics solution would most
likely involve the resonant production of a non-interacting neutrino of
mass --50 keV. We propose a model where anisotropic magnetic
field configurations strongly bias the resonant spin flavour precession of tau
antineutrinos into . For internal magnetic fields B_{int} \gsim
10^{15} G a - transition magnetic moment of the order of
Bohr magnetons is required. The asymmetric emission of from
the core can produce sizeable natal kicks and account for recoil velocities of
several hundred kilometers per second.Comment: 14 pages, AASTEX, 2 figures (uses epsfig). Minor typos corrected.
Added acknowledgments to the funding institutes BID and Colciencia
First results from the MIT optical rapid imaging system (MORIS) on the IRTF: A stellar occultation by Pluto and a transit by exoplanet XO-2b
We present a high-speed, visible-wavelength imaging instrument: MORIS (the MIT Optical Rapid Imaging System). MORIS is mounted on the 3 m Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. Its primary component is an Andor iXon camera, a nearly 60" square field of view with high quantum efficiency, low read noise, low dark current, and full-frame readout rates ranging from as slow as desired to a maximum of between 3.5 Hz and 35 Hz (depending on the mode; read noise of 6 pixel and 49 pixel with electron-multiplying gain = 1 , respectively). User-selectable binning and subframing can increase the cadence to a few hundred hertz. An electron-multiplying mode can be employed for photon counting, effectively reducing the read noise to subelectron levels at the expense of dynamic range. Data cubes, or individual frames, can be triggered to several-nanosecond accuracy using the Global Positioning System. MORIS is mounted on the side-facing exit window of SpeX, allowing simultaneous near-infrared and visible observations. Here, we describe the components, setup, and measured characteristics of MORIS. We also report results from the first science observations: the 2008 June 24 stellar occultation by Pluto and an extrasolar planetary transit by XO-2b. The Pluto occultation of a 15.8 magnitude star has a signal-to-noise ratio of 35 per atmospheric scale height and a midtime error of 0.32 s. The XO-2b transit reaches photometric precision of 0.5 mmag in 2 minutes and has a midtime timing precision of 23 s.United States. National Aeronautics and Space Administration (grant NNX07AK95G
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Overexpression of the MYB29 transcription factor affects aliphatic glucosinolate synthesis in Brassica oleracea
Isothiocyanates, the bio-active hydrolysis products of glucosinolates, naturally produced by several Brassicaceae species, play an important role in human health and agriculture. This study aims at correlating the content of aliphatic glucosinolates to the expression of genes involved in their synthesis in Brassica oleracea, and perform functional analysis of BoMYB29 gene. To this purpose, three genotypes were used: a sprouting broccoli, a cabbage, and a wild genotype (Winspit), a high glucosinolate containing accession. Winspit showed the highest transcript level of BoMYB28, BoMYB29 and BoAOP2 genes, and BoAOP2 expression was positively correlated with that of the two MYB genes. Further analyses of the aliphatic glucosinolates also showed a positive correlation between the expression of BoAOP2 and the production of sinigrin and gluconapin in Winspit. The Winspit BoMYB29 CDS was cloned and overexpressed in Winspit and in the DH AG1012 line. Overexpressing Winspit plants produced higher quantities of alkenyl glucosinolates, such as sinigrin. Conversely, the DH AG1012 transformants showed a higher production of methylsulphinylalkyl glucosinolates, including glucoraphanin, and, despite an up-regulation of the aliphatic glucosinolate genes, no increase in alkenyl glucosinolates. The latter may be explained by the absence of a functional AOP2 gene in DH AG1012. Nevertheless, an extract of DH AG1012 lines overexpressing BoMYB29 provided a chemoprotective effect on human colon cells. This work exemplifies how the genetic diversity of B. oleracea may be used by breeders to select for higher expression of transcription factors for glucosinolate biosynthesis to improve its natural, health-promoting properties
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