Edible oleogels in molecular gastronomy

AbstractExperimental chefs and researchers have limited options when structuring lipid-based materials present in foods to include: liquids, solids, foams or emulsions. However, the application of gel technology for lipids is on the cusp of advancing into experimental culinary kitchens around the world. The possibility of utilizing edible oils (and even ethanol) to extract a hydrophobic flavor and then gel the material in a similar fashion as hydrocolloids gel water is now a reality. This review covers the three primary oleogels: ethyl cellulose, mixtures of γ-oryzanol and β-sitosterol and candelilla wax

Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis

Background Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy. Methods We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance. Results We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography. Conclusion Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data

Bioinformatics and molecular modeling in glycobiology

The field of glycobiology is concerned with the study of the structure, properties, and biological functions of the family of biomolecules called carbohydrates. Bioinformatics for glycobiology is a particularly challenging field, because carbohydrates exhibit a high structural diversity and their chains are often branched. Significant improvements in experimental analytical methods over recent years have led to a tremendous increase in the amount of carbohydrate structure data generated. Consequently, the availability of databases and tools to store, retrieve and analyze these data in an efficient way is of fundamental importance to progress in glycobiology. In this review, the various graphical representations and sequence formats of carbohydrates are introduced, and an overview of newly developed databases, the latest developments in sequence alignment and data mining, and tools to support experimental glycan analysis are presented. Finally, the field of structural glycoinformatics and molecular modeling of carbohydrates, glycoproteins, and protein–carbohydrate interaction are reviewed

Design and performance of a resistor multiplexing readout circuit for a SiPM detector

A silicon photomultiplier (SiPM)-based positron emission tomography (PET) detector was developed using a resistor network charge division multiplexing circuit for detector readout. The detector consists of a lutetium-yttrium oxy-orthosilicate (LYSO) scintillation crystal array, an SiPM array detector (SPMArray 4, SensL Inc., Cork, Ireland) and the resistor multiplexing network implemented in a through-hole package to facilitate changing of resistor values. For purposes of optimizing the readout circuit, the LYSO array used was a 4 7 4 crystal array with crystal size mm on a pitch of 3.37 mm, matched to the SiPM pixel size 3.17 7 3.17 7 10 mm3. Flood image, energy resolution, photopeak amplitude, timing resolution, and signal time-pickoff measurements were performed using standard NIM electronics. The resistor network values were optimized through an iterative process. The performance of the detector was evaluated over a range of temperatures from 23 \ub0C to 60 \ub0C by heating the detector. The ability of the detector to resolve crystals smaller than the SiPMpixel pitch was evaluated using a dual-layer LYSO array with crystals of 1.67-mm pitch. The optimal resistor network values were found to be 100 \u3c9 along the rows connecting the SiPM pixels and 56 \u3c9 for the columns. For these resistor value settings, the average energy resolution for the central four crystals in the array at 23.5 \ub0C was 13.3% \ub1 0.3% and degraded to 16.3% \ub1 0.3% at 60 \ub0C. The photopeak amplitude decreased by 2%/\ub0C, and the timing resolution degraded from 3.43 \ub1 0.22 ns to 4.64 \ub1 0.25 ns for a 350-750-keV energy window over this temperature range. The signal time-pickoff point shifted earlier by 2.7 ns as the temperature increased, an effect likely due to changes in the signal shape with temperature. The detector was able to resolve all 113 crystals in the dual-layer LYSO array. These results demonstrate that the resistor multiplexing readout circuit functions well for reading out SiPM array based detectors, which use scintillator crystal arrays much smaller than the SiPM pixel pitch. The reduced number of output signals achieved through this signal multiplexing greatly reduces the number of signal cables required. In addition, the ability of this detector to function over a wide range of temperatures offers significant flexibility in defining the system operating temperature set point. \ua9 1963-2012 IEEE.Peer reviewed: YesNRC publication: Ye

Fetal hemodynamics and cardiac streaming assessed by 4D flow cardiovascular magnetic resonance in fetal sheep

Abstract Background To date it has not been possible to obtain a comprehensive 3D assessment of fetal hemodynamics because of the technical challenges inherent in imaging small cardiac structures, movement of the fetus during data acquisition, and the difficulty of fusing data from multiple cardiac cycles when a cardiac gating signal is absent. Here we propose the combination of volumetric velocity-sensitive cardiovascular magnetic resonance imaging (“4D flow” CMR) and a specialized animal preparation (catheters to monitor fetal heart rate, anesthesia to immobilize mother and fetus) to examine fetal sheep cardiac hemodynamics in utero. Methods Ten pregnant Merino sheep underwent surgery to implant arterial catheters in the target fetuses. Anesthetized ewes underwent 4D flow CMR with acquisition at 3 T for fetal whole-heart coverage with 1.2–1.5 mm spatial resolution and 45–62 ms temporal resolution. Flow was measured in the heart and major vessels, and particle traces were used to visualize circulatory patterns in fetal cardiovascular shunts. Conservation of mass was used to test internal 4D flow consistency, and comparison to standard 2D phase contrast (PC) CMR was performed for validation. Results Streaming of blood from the ductus venosus through the foramen ovale was visualized. Flow waveforms in the major thoracic vessels and shunts displayed normal arterial and venous patterns. Combined ventricular output (CVO) was 546 mL/min per kg, and the distribution of flows (%CVO) were comparable to values obtained using other methods. Internal 4D flow consistency across 23 measurement locations was established with differences of 14.2 ± 12.1%. Compared with 2D PC CMR, 4D flow showed a strong correlation (R2 = 0.85) but underestimated flow (bias = − 21.88 mL/min per kg, p < 0.05). Conclusions The combination of fetal surgical preparation and 4D flow CMR enables characterization and quantification of complex flow patterns in utero. Visualized streaming of blood through normal physiological shunts confirms the complex mechanism of substrate delivery to the fetal heart and brain. Besides offering insight into normal physiology, this technology has the potential to qualitatively characterize complex flow patterns in congenital heart disease phenotypes in a large animal model, which can support the development of new interventions to improve outcomes in this population

Data from: Mother-offspring distances reflect sex differences in fine-scale genetic structure of eastern grey kangaroos

Natal dispersal affects life history and population biology and causes gene flow. In mammals, dispersal is usually male-biased so that females tend to be philopatric and surrounded by matrilineal kin, which may lead to preferential associations among female kin. Here we combine genetic analyses and behavioral observations to investigate spatial genetic structure and sex-biased dispersal patterns in a high-density population of mammals showing fission–fusion group dynamics. We studied eastern grey kangaroos (Macropus giganteus) over 2 years at Wilsons Promontory National Park, Australia, and found weak fine-scale genetic structure among adult females in both years but no structure among adult males. Immature male kangaroos moved away from their mothers at 18–25 months of age, while immature females remained near their mothers until older. A higher proportion of male (34%) than female (6%) subadults and young adults were observed to disperse, although median distances of detected dispersals were similar for both sexes. Adult females had overlapping ranges that were far wider than the maximum extent of spatial genetic structure found. Female kangaroos, although weakly philopatric, mostly encounter nonrelatives in fission–fusion groups at high density, and therefore kinship is unlikely to strongly affect sociality