CT is the imaging modality of choice to study the paranasal sinuses; unfortunately, it involves significant radiation dose. Our aim was to assess the diagnostic validity, image quality, and ...radiation-dose savings of dental conebeam CT in the evaluation of patients with suspected inflammatory disorders of the paranasal sinuses.
We prospectively studied 40 patients with suspected inflammatory disorders of the sinuses with dental conebeam CT and standard CT. Two radiologists analyzed the images independently, blinded to clinical information. The image quality of both techniques and the diagnostic validity of dental conebeam CT compared with the reference standard CT were assessed by using 3 different scoring systems. Image noise, signal-to-noise ratio, and contrast-to-noise ratio were calculated for both techniques. The absorbed radiation dose to the lenses and thyroid and parotid glands was measured by using a phantom and dosimeter chips. The effective radiation dose for CT was calculated.
All dental conebeam CT scans were judged of diagnostic quality. Compared with CT, the conebeam CT image noise was 37.3% higher (P < .001) and the SNR of the bone was 75% lower (P < .001). The effective dose of our conebeam CT protocol was 23 μSv. Compared with CT, the absorbed radiation dose to the lenses and parotid and thyroid glands with conebeam CT was 4%, 7.8%, and 7.3% of the dose delivered to the same organs by conventional CT (P < .001).
Dental conebeam CT is a valid imaging procedure for the evaluation of patients with inflammatory sinonasal disorders.
ABSTRACT
Gluten, starch, lipids, and water‐soluble material were separated from seven wheat samples with a range of protein contents and breadmaking quality. The isolated glutens were further ...partitioned into gliadin‐ and gluteninrich fractions using pH precipitation. Protein content and glutenin‐togliadin ratio were systematically altered by blending these fractions into the original flours in calculated amounts. Mixing properties, extension‐tester parameters, and baking performance of composite flours were determined using small‐scale techniques. Results of dough testing with blends of constant glutenin‐to‐gliadin ratio showed increases in the mixing time, mixograph peak resistance, maximum resistance to extension, extensibility, and loaf volume as the protein content increased. At constant protein content, increases in glutenin‐to‐gliadin ratio were associated with increases in mixing time, mixograph peak resistance, maximum resistance to extension, and loaf volume, and with decreases in extensibility. Thus, total protein content and glutenin‐to‐gliadin ratio independently affected dough and baking properties. The results have allowed the separation of the effects of flour protein quantity and composition on breadmaking properties.
This observational study included patients who underwent pre-operative coronavirus disease 2019 (COVID-19) screening in order to preserve patient safety. Reverse transcriptase polymerase chain ...reaction (PCR) for severe acute respiratory syndrome coronavirus-2 was performed in 2292 of 8740 surgical procedures, and the incidence of a positive PCR result was 0.0022%. No healthcare-associated infections were detected. There was no difference in overall mortality or length of hospital stay compared with the same period from the previous year. A selective screening strategy to identify patients for PCR testing, based on isolation measures, presurgical clinical-epidemiological assessment and selected major surgeries susceptible to a poor COVID-19-related outcome, is effective and safe for patients and healthcare workers.
Cations of differing chaotropic capacities (LiCl, NaCl, and KCl) were used in small-scale mixing and extensigraph studies to assess functional changes in dough behavior of wheat cultivars varying in ...total protein content and HMW glutenin composition. Salt addition, regardless of cationic type, caused an increase in dough strength and stability. The smaller (hydrated) and least chaotrophic cations (Li+<Na+<K+) effected the greatest increase in mixing time (MT) and resistance to extension (Rmax) and produced the most stable resistance breakdown (RBD). The effects of different cations on mixing and extensions indicated strong intercultivar variation; differential responses to salt addition were further shown when the cultivars were grouped according to protein content and Glu-1D or Glu-1B genome composition. Increases in dough strength parameters due to the addition of salt were consistently more significant for cultivars showing an overexpression of Bx7 (>12% protein). In the absence of genotypic variation, a significant interactive effect of cultivar type, protein amount, and salt addition was found for all functional dough parameters except extensibility. During mixing, there was a decrease in the amount of apparent unextractable polymeric protein (%UPP) in the dough. This phenomenon was ameliorated by the presence of salt in doughs formed from weaker flours and was most pronounced early on in the mixing process (t = 100-200 sec). Results show the importance of refining 2-g mixograph studies to include salt in the “flour and water” dough formula.
This study applied the use of a new small-scale apparatus, the micro Z-arm mixer, which has analogous mixing action to that of the traditional valorigraf and farinograph. A novel methodology has been ...developed for prediction of water absorption replacing the traditional titration method. The basis of this technique is a common characteristic of wheat flour samples: a reasonably constant slope (20-25.7 BU%) of the relationship between dough resistance and the amount of water present during mixing. Using an average slope value, prediction of water absorption was possible from a single measurement using a simple equation and with a standard error of 1.65%. Applications of the new mixer to cereal research are highlighted, including investigation of the effects of flour protein content and protein composition on mixing properties and water absorption. When protein content and protein composition have been systematically altered by the addition of isolated proteins into the flour, both dough development time (DDT) and water absorption increased when protein content was increased by glutenin addition and decreased when protein content was decreased by starch addition. Gliadin addition decreased DDT; gluten addition slightly increased DDT; glutenin addition significantly increased DDT. Water absorption was not affected by altering the glutenin-to-gliadin ratio, but it changed in proportion to the amount of protein added. The effect of HMW-GS composition on the mixing requirement obtained with the micro Z-arm mixer and with the 2-g mixograph was also investigated using a set of single-, double-, and triple-null lines for HMW-GS coding genes. While subunits coded on the GluD1 locus were most important for determining the mixing requirement in both cases, the sample ranking was different in the two mixing actions. A better differentiation ability of the micro Z-arm mixer was established for triple- and double-null lines.
Modern cereal science has progressed to the point where a more detailed and explicit understanding of the rheological properties of wheat-flour dough at the molecular level is required in order to ...improve plant breeding methodologies, the manufacturing of wheat-flour dough products and the assessment of wheat and wheat-flour quality. The formulation of molecular models provides a basis for predictive tests that can be combined with other protocols. The actual modelling must, in turn, be based on experiments which directly monitor the changing rheology of the dough which occurs during mixing, as it is this evolving rheology which in effect monitors the dough at a molecular level. There are various ways in which this can be done. The perspective adopted here is that, at least on a MixographTM, the mixing of the dough can be viewed as a series of extension tests. It therefore follows that one way to monitor the evolving rheology of a wheat-flour dough during mixing is to perform extension tests on the dough at various stages during the mixing. The results obtained from such experiments are reported in this paper. They show how the study of the evolving rheology of a wheat-flour dough, during mixing with varying amounts of added water, in effect monitors the molecular processes occurring during mixing in terms of the behaviour of the bonded and unbonded water within the dough. In addition, these results yield confirming evidence for the hypothesis, tentatively proposed by various authors, that the bandwidth of a Mixogram is a key (qualitative) characteristic of a dough for assessing its strength. Together, both these conclusions imply that, as well as a measure of the strength and quality of the dough being mixed, the variation in the bandwidth of a Mixogram is indicative of the role played by the added water during the mixing.
We evaluated prospectively the occurrence of seizures within 15 days of a first stroke or transient ischemic episode in 1,640 patients to study relation between seizures and type of stroke. Seizures ...occurred in 90 patients (5.4%), including 36 (4.4%) of 814 with infarct owing to atheroma, 21 (16.6%) of 126 with infarct owing to cardiogenic embolus, 3 (1%) of 273 owing to lacunar infarct, 5 (1.9%) of 259 owing to transient ischemic attack (TIA), 21 (16.2%) of 129 owing to supratentorial hematoma, and 4 (16.6%) of 24 owing to subarachnoid hemorrhage. Thirteen (14.6%) of 89 subcortical infarcts were associated with seizures. Seizures were the initial sign of stroke in 80 (89%) of 90 cases and were usually single and partial. Seizure symptoms were most often motor, sensory, or visual.
The extension testing of wheat-flour dough has become one of the key cereal chemistry links to end product quality assessment, because of its perceived relevance to baking performance, and because of ...the various correlations that have been inferred and assumed since the extensibility of a dough was first investigated in the late 19th century. As a consequence, from a plant breeding perspective, there is a need to understand and interpret the extensibility of a dough in terms of the molecular dynamics occurring during its extension, not only as it relates to its baking, but also to the HMW/LMW glutenin and gliadin composition of the wheat. The focus of this paper is the direct measurement of extensibility on a micro-extension tester. The theoretical justification is that the resulting extensogram represents an encapsulation of the extensional rheology of the dough. The paper reports on a graphical and statistical analysis of extension tests performed on eight representative flours. They yield validation for the conclusion that the historic assessment of extensibility as Ext
Rupture should be replaced by Ext
Rmax and the difference Ext
Rupture−Ext
Rmax. It is relatively easy to obtain accurate estimates of
R
max, Ext
Rmax and Ext
Rupture from electronically recorded extensograms. Among other things, it is established that, in terms of the glutenin classification of flours based on electrophoresis, HPLC or DNA markers,
R
max yields a far better differentiation than is achieved with either Ext
Rupture or Ext
Rmax. It follows, as a corollary to such results, that the extensions to the earlier rheological phases in an extensogram are just as, if not more, important in identifying connections between the gluten composition of wheat varieties and the traditional Ext
Rupture and
R
max. In particular, it is shown that, like
R
max, the scaled difference
R
max/(Ext
Rupture−Ext
Rmax) represents an alternative strategy to relate quality to the glutenin composition of wheat varieties, determined by electrophoresis, HPLC and DNA markers.
ABSTRACT
The development of reduction‐oxidation methods to open the native gluten polymer, incorporate monomers, and repolymerize the modified polymer, has allowed new types of investigation of the ...effects of glutenin subunits on dough characters. These methods were used to incorporate bulk high molecular weight glutenin subunits (HMW‐GS) and bulk low molecular weight glutenin subunits (LMW‐GS) from four cultivars into the parent flours to modify the HMW‐GS‐to‐LMW‐GS ratio. In addition, the glutenins from the four cultivars were added to a single base flour of differing glutenin subunit composition. Finally, HMW‐GS 7, 8, 5, and 10 were incorporated singly and in pairs into two base flours. The mixing time, peak resistance, maximum resistance to extension, and loaf height increased with increases in HMW‐GS‐to‐LMW‐GS ratio. There was a decrease in resistance breakdown observed with increase in HMW‐GS‐to‐LMW‐GS ratio. The maximum resistance to extension slightly increased with increases in HMW‐GS‐to‐LMW‐GS ratio (strongly in cultivar Hartog). Dough extensibility decreased with increase in HMW‐GS‐to‐LMW‐GS ratio (except in Osprey derivative). In the incorporation studies of single and paired glutenin subunits, HMW‐GS 5+10 gave a synergistic effect increasing mixing time, maximum resistance to extension, and loaf height as compared with HMW‐GS 5 or 10 separately. In contrast, HMW‐GS 7+8 showed an additive effect and HMW‐GS 7 incorporated separately had a higher mixing time, maximum resistance to extension, and loaf height than those of HMWGS 7+8 and HMW‐GS 8.
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