Radiology quiz case 4. McCune-Albright syndrome Verdaguer, José M; Lobo, David; García-Berrocal, José R ...
Archives of otolaryngology--head & neck surgery
131, Številka:
2
Journal Article
The constant growing in traffic demands has driven to look for new methods with which to reduce the occupied bandwidth and efficient use of the optical spectrum. Despite non-orthogonal signalling ...lead to intersymbolic interference introduction, it can be considered as a promising solution if interference is introduced in a controlled manner. In this paper the modulation scheme called Faster-Than-Nyquist (FTN) is presented for Flexible Passive Optical Networks application. Different ratios of bandwidth reduction vs. power penalty are presented and compared to the Nyquist modulation.
Greenhouse-grown pigeonpea (Cajanus cajan, L. Millsp.; cultivar UW-10) and cowpea (Vigna unguiculata, L. Walp.; cultivar California No. 5) were well-watered (control) or subjected to low water ...potential by withholding water to compare their modes of adaptation to water-limited conditions. Leaf CO2 exchange rate (CER), leaf diffusive conductance to CO2 ($g_{L}$), and CO2 concentration in the leaf intercellular air space ($\text{C}_{i}$) were determined at various CO2 concentrations and photon flux densities (PFD) of photosynthetically active radiation (400 to 700 nanometer). In cowpea, $g_{L}$ declined to less than 15% of controls and total water potential ($\Psi _{w}$) at midafternoon declined to -0.8 megapascal after 5 days of withholding water, whereas $g_{L}$ in pigeonpea was about 40% of controls even though midafternoon $\Psi _{w}$ was -1.9 megapascal. After 8 days of withholding water, $\Psi _{w}$ at midafternoon declined to -0.9 and -2.4 megapascals in cowpea and pigeonpea, respectively. The solute component of water potential ($\Psi _{s}$) decreased substantially less in cowpea than pigeonpea. Photosynthetic CER at saturation photon flux density (PFD) and ambient external CO2 concentration (360 microliters per liter) on day 5 of withholding decreased by 83 and 55% in cowpea and pigeonpea, respectively. When measured at external, CO2 concentration in bulk air of 360 microliters per liter, the CER of cowpea had fully recovered to control levels 3 days after rewatering; however, at 970 microliters per liter the PFD-saturated CERs of both species were substantially lower than in controls, indicating residual impairment. In stressed plants of both species the CER responses to $\text{C}_{i}$ from 250 to 600 microliters per liter indicated that a substantial nonstomatal inhibition of CER had occurred. Although the sensitivity of $g_{L}$ to water limitation in cowpea suggested a dehydration avoidance response, parallel measurements of CER at various $\text{C}_{i}$ and PFD indicated that photosynthetic activity of cowpea mesophyll was substantially inhibited by the water-limited treatment.
Flex-Grid 6.25GHz full-duplex frequency slots are proposed for Metro/Access & Data-Center Networks allocating: 1Gbps Nyquist-DPSK over MZM for OLT/DC-ONU downlinks and OLT/DC up-downlinks; 1Gbps ...NRZ-DPSK over directly modulated DFB for ONU-OLT/DC uplinks; with 50km single fiber transmission.
There is a paucity of data regarding Alzheimer's disease (AD) patients' longitudinal deterioration in the ability to conduct numerous activities required for daily living. In this study, 52 patients ...with AD were assessed at baseline and at a 1-year follow-up using the Direct Assessment of Functional Status (DAFS) scale, an objective, well-validated measure of a broad spectrum of functional capacities that is administered within the clinical setting. An important finding was that the level of initial performance on each of the 11 functional tasks measured did not relate to the degree of functional decline in that particular area. Communication skills, such as using the telephone (deterioration among 35.4% of the patients) and preparing a letter for mailing (deterioration among 32.7%), showed the most frequent deterioration among patients upon follow-up. More than half of the AD patients studied demonstrated impairment on one or both of these measures. The pattern of findings indicates that many subtests of the DAFS were sensitive to functional decline after a 1-year period and that the scale has utility in objectively establishing longitudinal patterns of deterioration.
A genetic polymorphism in S-acetyl coenzyme A (AcCoA)-dependent N-acetyltransferase has been associated with a differential risk for certain cancers in humans. In this study, several tissues from the ...inbred Syrian hamster with a genetically defined AcCoA-dependent N-acetyltransferase polymorphism (homozygous rapid acetylator, Bio. 87.20; homozygous slow acetylator, Bio. 82.73/H; and heterozygous acetylator, Bio. 87.20 X Bio. 82.73/H F1), were investigated for the relationship of arylamine N-acetyltransferase to the AcCoA-dependent metabolic activation of carcinogenic N-hydroxy (N-OH)-arylamines to bind to DNA (O-acetyltransferase). The levels of both 2-aminofluorene (AF) N-acetyltransferase and N-OH-AF O-acetyltransferase activity reflected the N-acetylator genotype in liver, intestine, kidney and lung cytosols. A significant acetylator gene--dose response for AF N-acetyltransferase and N-OH-AF O-acetyltransferase activities was observed in liver and lung cytosols. In contrast, acetylator genotype was not consistently expressed for the AcCoA-dependent N-acetylation of 4-aminobiphenyl (ABP), nor for the AcCoA-dependent metabolic activation of N-OH-ABP and N-OH-3,2'-dimethyl-4-aminobiphenyl in these same tissue cytosols. Two peaks of acetyltransferase activity were partially purified by ion exchange FPLC chromatography from the hepatic cytosol of both the homozygous rapid and homozygous slow acetylator hamster. In contrast to unfractionated cytosol, the isozyme(s) eluting first clearly demonstrated levels of AcCoA-dependent arylamine N-acetyltransferase and N-OH-arylamine O-acetyltransferase activities that were consistent with N-acetylator genotype (polymorphic) for all substrates tested. In contrast, the slower eluting isozyme(s) in each acetylator cytosol showed levels of AcCoA-dependent N- and O-acetyltransferase activities that did not vary with N-acetylator genotype (monomorphic). The AcCoA-dependent O-acetyltransferase activity of both the monomorphic and polymorphic peaks was paraoxon resistant. These studies demonstrate acetylator genotype-dependent control of AcCoA-dependent metabolic activation of N-OH-arylamines(O-acetylation) by polymorphic isozyme(s) similar to that for AcCoA-dependent N-acetylation of arylamines in the hamster. The polymorphic genetic control of N-OH-arylamine O-acetyltransferase may be an important risk factor for arylamine-induced cancer, in those species and tissues expressing appreciable levels of O-acetyltransferase activity.
Acetyl coenzyme A-dependent arylamine N-acetyltransferase (EC 2.3.1.5) was examined in bladder cytosol derived from inbred Syrian hamsters. Expression of N-acetyltransferase activity towards ...p-aminobenzoic acid, p-aminosalicylic acid and 2-aminofluorene was acetylator genotype-dependent. Highest levels of bladder N-acetyltransferase activity were expressed in homozygous rapid acetylator hamsters (Bio. 87.20), lowest levels in homozygous slow acetylator hamsters (Bio. 82.73/H), and intermediate levels in Bio. 87.20 X Bio. 82.73/H F1 generation progeny. The N-acetyltransferase activity was acetylator genotype-dependent in both epithelial and non-epithelial bladder tissue. Genetic crosses using p-aminobenzoic acid and p-aminosalicylic acid as substrates indicated that bladder N-acetyltransferase activity is controlled via simple autosomal Mendelian inheritance of two codominant alleles at a single genetic locus. Acetylator genotype as assessed by bladder N-acetyltransferase activity was completely concordant with acetylator genotype as assessed by liver N-acetyltransferase activity. N-Acetyltransferase in slow acetylator bladder cytosol was both an apparent Km and Vmax variant compared to N-acetyltransferase in rapid acetylator bladder cytosol. These results suggest that genetic control of arylamine N-acetyltransferase in bladder urothelium may be a factor in hereditary predisposition to arylamine-induced bladder cancer.
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