by all solutions at 0 of the system is o-minimal. We also show that if the coefficients of the system have a Taylor development of sufficiently large finite order, then the question of which of the ...two cases holds can be effectively determined in terms of the coefficients of this Taylor development.>
Zucchini yellow mosaic virus (ZYMV) is a member of genus Potyvirus, family Potyviridae. ZYMV is a positive-strand RNA virus. Virions are flexuous filaments of 680-730 nm in length and 11-13 nm in ...diameter, composed of about 2000 subunits of a single 31-kDa protein (calculated). The genome RNA size is 9.6 kb covalently linked to a viral-encoded protein (the VPg) at the 5' end, and with a 3' poly A tail. The 5' end of the sequence is AU-rich (69%). The genome is expressed as a polyprotein cleaved by three viral proteases and processed into ten putative mature proteins. The structural coat protein is processed from the carboxyl terminus of the polyprotein and is highly immunogenic. Natural and experimental infection has been reported mainly in the Cucurbitaceae. Experimental local lesion hosts include Chenopodium amaranticolour, C. quinoa and Gomphrena globosa. Some ZYMV strains cause symptomless infection as in Ranunculus sardous, Nicotiana benthamiana and Sesamum indicum. ZYMV causes stunting and major foliar deformation with dark green blisters and mosaics in cucurbit hosts, eventually developing a filamentous leaf phenotype. In general, symptoms are severe on cucurbit hosts and cause dramatic reductions in yields due to severe fruit deformation. The virus is present in all the plant tissues at relatively high concentrations (c. 0.1 mg/mL of purified virus per 1 g fresh leaf tissue). The most suitable species for maintenance and purification is Cucurbita pepo. ZYMV is efficiently transmitted by aphids in a non-persistent manner. The coat protein (CP) and the helper component-protease (HC-Pro) are required for aphid transmission, through the CP DAG motif and the HC-Pro KLSC and PTK motifs. Mechanical transmission is efficient both in the laboratory and naturally. ZYMV disease is a major constraint in the production of cucurbits world-wide. The virus can cause massive damage (to total loss) to cucurbit crops, and prevents the growth of some cucurbit crops in certain areas. Control of ZYMV requires the integration of conventional resistance and transgenic breeding along with cross-protection technologies.
We present preliminary tests of hybrid pixel detectors consisting of the Medipix2 readout chip bump-bonded to a 1-mm-thick CdTe pixel detector. This room temperature imaging system for single photon ...counting has been developed within the Medipix2 European Collaboration for various imaging applications with X-rays and gamma rays, including dental radiography, mammography, synchrotron radiation, nuclear medicine, and radiation monitoring in nuclear facilities. The Medipix2 + CdTe hybrid detector features 256 /spl times/ 256 square pixels, a pitch of 55 /spl mu/m, a sensitive area of 14/spl times/14 mm/sup 2/. We analyzed the quality of the detector and bump-bonding and the response to nuclear radiation of the first CdTe hybrids. The CdTe pixel detectors, with Pt ohmic contacts, showed an ohmic response when negatively biased up to less than 60 V (electrons collection mode). Tests were also performed in holes collection mode, where a nonresistive behavior was observed above +15 V. We performed a series of imaging tests at low voltage bias with gamma radioactive sources and with an X-ray tube. Under uniform irradiation, we observed for all detectors the presence of numerous, stable structures in the form of small circles of about 200 /spl mu/m diameter, with the central pixels showing a reduced counting efficiency with respect to the periphery (in electrons counting regime). Also long filament structures have been observed. Further investigations will reveal whether they are due to an intrinsic detector response (e.g., due to Te inclusions) or to the bump-bonding process.
Abstract
INTRODUCTION
Meningioma is the most prevalent primary tumor in the central nervous system (CNS). Although mostly benign, 15- 20% are aggressive and tend to recur and progress despite surgery ...and adjuvant radiation. Recent publications show that bevacizumab, a vascular endothelial growth factor inhibitor, effectively treats these refractory meningiomas. The standard method to monitor treatment’s effect on imaging is Response Assessment in Neuro-Oncology criteria (RANO). Recently, an alternative tool called 3D volumetric growth rate (3DVGR) has emerged as a result of significant advancements in the accuracy of volumetric measurement techniques. Our aim is to compare the effectiveness of conventional RANO criteria and the emerging 3DVGR measure in evaluating the response to bevacizumab treatment in patients with refractory meningiomas. We will also assess their correlation with clinical outcomes over a period of up to 9 months.
METHODS
68 MRI scans of 20 patients with aggressive meningiomas that progressed after radiation therapy and then received Bevacizumab were evaluated. Scans were obtained from two tertiary cancer centers. For each tumor both RANO and 3DVGR were conducted in two subsequent head MRI studies acquired prior to the initiation of bevacizumab treatment and then in at least one exam within 6 months post-treatment. Measurements were obtained using PACS and BRAIN LAB software by two radiologists.
RESULTS
A total of 43 lesions derived from 13 males and 7 females were included in the final analysis. The mean age was 65.5; mean number of pre-radiation treatments was 2.66; mean number of pre-surgical treatments was 2.7 and mean number of bevacizumab cycles was 22.7. All lesions showed a decrease or stabilization in growth rate compared to baseline. More specifically, 34 out of 43 lesions (79%) showed a negative growth rate value indicating decrease in tumor size. Comparison of treatment response using RANO criteria was not always in concordance with the 3DVGR measurement and showed inaccurate correlation with clinical outcome.
CONCLUSIONS
Although widely accepted for treatment response evaluation, RANO criteria are not an accurate technique for irregularly shaped lesions. As shown in our study, for atypical meningiomas, the 3DVGR measure seems to be more precise compared to RANO criteria. Furthermore, our results show great promise for treatment of refractory meningiomas with bevacizumab.
The rapid development of the gastrointestinal tract posthatch has been described; however, little information exists concerning the development of the small intestine in the prehatch period. The ...present study examined the morphological, cellular, and molecular changes occurring in the small intestine toward the end of the incubation period by examining the expression of intestinal genes that code for brush border digestive enzymes and transporters, their biochemical activities, and the morphological changes in the mucosal layer. The results indicated that during the last 3 d of incubation the weight of the intestine, as a proportion of embryo weight, increased from approximately 1% on d 17 of embryonic age to 3.5% at hatch. At this time the villi could be divided into two main developmental stages, differing in their length and shape, with the larger villi often being pear-shaped and the smaller villi being narrower and having a rocket-like shape. However, on d 19 a further stage of villus development was observed. Activities of maltase, aminopeptidase, sodium-glucose transporter (SGLT)-1, and ATPase began to increase on d 19 and further increased on the day of hatch. The expression of mRNA for these brush-border membrane (BBM) enzymes and transporters was detected from d 15. Determining quantities relative to beta-actin indicated that expression of all parameters examined was low on d 15 and 17, increased 9- to 25-fold on d 19, and all decreased again on the day of hatch. Relative expression of mRNA of the different enzymes and transporters were correlated as were their activities (r = 0.75 to 0.96); however, expression was not correlated with enzymatic activities. The role of these parameters in the ontogeny of absorption is discussed. Thus, major changes in the expression and localization of the functional brush-border proteins prepare the framework for ingestion of carbohydrate- and protein-rich exogenous feed posthatch.
We have tested the high-energy imaging capabilities of detectors made of a Medipix1 pixel photon-counting chip hybridized with a 300μm thick Si or a 200μm thick GaAs substrate. The results presented ...in this paper show that an important part of the signal is due to secondary particles coming from γ-ray diffusion in the detector surroundings. According to simulation studies realized with the Monte-Carlo code PENELOPE, the contribution of a 2mm thick Pyrex screen placed between the source (60Co) and the Si detector can reach 75% of the total number of counts. The main reason for this high relative sensitivity of the substrate to the secondary particles is its very poor detection efficiency at high γ-ray energies. We also present results for imaging with a double-cone pinhole collimator, through comprehensive comparisons between experiment and simulation.
The first prototypes of a Medipix2 chip hybridized with a 1mm thick pixel CdTe substrate have been carried out and we present experimental tests done with γ-ray sources at high energies (up to 1.33MeV). We also present results obtained with a dedicated pseudo-Monte-Carlo 3D simulation code. This simulation code, whose first stage is the single-event energy-deposition distribution, processes the charge-carrier transport taking into account trapping and diffusion and, at the same time, registers the induced signal on pixels. The first confrontations with experimental measurements are shown.
The influence of photoperiod manipulation in the dry period was examined in dairy goats experiencing environmental heat stress. Multiparous Israeli Saanen goats were blocked at dry off (∼60d ...prepartum) into 2 groups of 4 goats each based on body weight, previous milk production, and detected embryo number. Treatments consisted of long-day (16h light:8h dark) and short-day (8h light:16h dark) photoperiods (LDPP and SDPP, respectively). Heat-stress conditions were applied by manipulating the environment of metabolic rooms to reach a maximum temperature of 37°C between 1000 and 2200h, and a minimum of 23°C and 70.3% relative humidity. All goats were returned to ambient photoperiod after kidding, milked twice daily, and milk yield was automatically recorded. Dry matter intake during the dry period was similar between treatments, averaging 1,114g/d. Milk production was significantly higher in the SDPP than the LDPP group (2,172 vs. 1,550g/d) during the 12-wk experimental period. Milk protein and fat contents were similar in both groups and averaged 3.63 and 4.34%, respectively, whereas milk lactose was higher in the LDPP group (4.77 vs. 4.67%). Heart rates were similar between treatments and averaged 112.6 beats per minute (BPM). Respiration rates were lower in the morning (58.4BPM) compared with the afternoon (91.2BPM) and were not influenced by photoperiod. Rectal temperature was higher for the LDPP than the SDPP group (40.4 vs. 39.6°C). The thyroid hormone level (mean ± SE) was similar in both groups during the dry period, but higher during lactation in the LDPP goats up to 40d postpartum (110±6.59 vs. 156±8.76ng/mL). Plasma IGF-1 (mean ± SE) was higher in the LDPP group (279±62 vs. 162±27ng/mL in SDPP) during the dry period but was similar postkidding, averaging 132±24ng/mL. Plasma prolactin level (mean ± SE) was higher in the LDPP than the SDPP group during the dry period (17.2±1.6 vs. 10.6±0.99ng/mL), whereas it was similar throughout lactation (0.61±0.28ng/mL). These data support the idea that SDPP manipulation during heat load in dry goats can be used as an abatement strategy to reduce the carryover effect of heat stress observed during the subsequent lactation. The higher milk production in SDPP goats is explained by changes in circulating prolactin profile rather than differences in feed intake or secretion of insulin-like growth factor 1.
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