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This paper presents the results of a numerical investigation of the gap influence on the turbine efficiency. The rotor-stator interaction in a (1/2)-stage turbine is simulated by solving the quasi-three-dimensional unsteady Euler/Navier-Stokes equations using a parallelized numerical algorithm. The reduced turnaround time and cost/MFLOP of the parallel code was crucial to complete the numerous run cases presented in this paper. The inter-row gap effect is evaluated for 4 gaps, 3 radial positions and 3 angular velocities. As expected, the results presented in this paper show that the efficiency increases and losses decrease while the gap size increases. The maximum efficiency location, however, corresponds to values of the gap size which may be too large for practical use (approximately inch). Fortunately, a local maximum efficiency and minimum losses location has been found at approximately 0.5 inches gap size. The efficiency variation near the local optimum is large, in some configurations being as high as 1.4 points for a gap size variation of only 0.076 inches. Data produced by the numerical simulations can be used to develop a design rule based on the inter-row gap size.

Colorectal cancers are one of the most prevalent tumour types worldwide and, despite the emergence of targeted and biologic therapies, have among the highest mortality rates. The Personalized OncoGenomics (POG) program at BC Cancer performs whole genome and transcriptome analysis (WGTA) to identify specific alterations in an individual's cancer that may be most effectively targeted. Informed using WGTA, a patient with advanced mismatch repair-deficient colorectal cancer was treated with the antihypertensive drug irbesartan and experienced a profound and durable response. We describe the subsequent relapse of this patient and potential mechanisms of response using WGTA and multiplex immunohistochemistry (m-IHC) profiling of biopsies before and after treatment from the same metastatic site of the L3 spine. We did not observe marked differences in the genomic landscape before and after treatment. Analyses revealed an increase in immune signalling and infiltrating immune cells, particularly CD8+ T cells, in the relapsed tumour. These results indicate that the observed anti-tumour response to irbesartan may have been due to an activated immune response. Determining whether there may be other cancer contexts in which irbesartan may be similarly valuable will require additional studies. [ABSTRACT FROM AUTHOR]

Continued monitoring of ankle sprain rates and distributions is needed to assess temporal patterns and gauge how changes in incidence may be associated with prevention efforts. To describe the epidemiology of ankle sprains in 16 US high school sports during the 2011–2012 to 2018–2019 school years. Descriptive epidemiology study. Online injury surveillance from high school sports. High school athletes who participated in practices and competitions during the 2011–2012 to 2018–2019 school years. A convenience sample of high school athletic trainers provided injury and athlete-exposure (AE) data to the National High School Sports-Related Injury Surveillance Study (data provided by High School Reporting Information Online [HS RIO]). Ankle sprain rates per 10 000 AEs with 95% CIs and distributions were calculated. Yearly rates were examined overall and by event type, injury mechanism, and recurrence. Overall, 9320 ankle sprains were reported (overall rate = 2.95/10 000 AEs; 95% CI = 2.89, 3.01). The highest sport-specific rates were reported in girls' basketball (5.32/10 000 AEs), boys' basketball (5.13/10 000 AEs), girls' soccer (4.96/10 000 AEs), and boys' football (4.55/10 000 AEs). Most ankle sprains occurred during competition (54.3%) and were due to contact with another person (39.5%) or noncontact (35.0%). Also, 14.5% of injuries were recurrent. Across the included academic years, ankle sprain rates generally increased. Compared with the 2011–2012 academic year, rates in the 2018–2019 academic year overall were 22% higher; noncontact-related and recurrent ankle sprain rates also generally increased by 91% and 29%, respectively. Time trends suggested that ankle sprain rates have increased across the past decade, particularly among those with noncontact-related mechanisms, contrasting with previous research that indicated decreases in incidence. These findings may pinpoint specific etiologic factors that should direct prevention efforts, including considering both person-contact and noncontact mechanisms by mitigating illegal contact through rule changes and enforcement, as well as bracing and proprioceptive and balance-training programs. [ABSTRACT FROM AUTHOR]

This paper introduces a coupling element to enhance the isolation between two closely packed antennas operating at the same frequency band. The proposed structure consists of two antenna elements and a coupling element which is located in between the two antenna elements. The idea is to use field cancellation to enhance isolation by putting a coupling element which artificially creates an additional coupling path between the antenna elements. To validate the idea, a design for a USB dongle MIMO antenna for the 2.4 GHz WLAN Band is presented. In this design, the antenna elements are etched on a compact low- cost FR4 PCB board with dimensions of 20 x 40 x 1.6 [mm.sup.3]. According to our measurement results, we can achieve more than 30 dB isolation between the antenna elements even though the two parallel individual planar inverted F antenna (PIFA) in the design share a solid ground plane with inter-antenna spacing (Center to Center) of less than 0.095[[lambda].sub.o] or edge to edge separations of just 3.6 mm (0.0294 [[lambda].sub.o]). Both simulation and measurement results are used to confirm the antenna isolation and performance. The method can also be applied to different types of antennas such as non-planar antennas. Parametric studies and current distribution for the design are also included to show how to tune the structure and control the isolation. Index Terms--Diversity antennas, multiple input and multiple output (MIMO), mutual coupling, planar inverted F antenna (PIFA), wireless communications.

New designs for compact reconfigurable antennas are introduced for mobile communication devices. The uniqueness of the antenna designs are that they allow various groups of their operating frequency bands to be selected electronically. In particular, each group of frequency bands, or mode, can be made to serve several different communication systems simultaneously. These systems may include various combinations of GSM, DCS, PCS, UMTS, Bluetooth, and wireless local-area network (LAN). Therefore, by electronically selecting different antenna modes, a variety of communication systems can be conveniently served by only one antenna. One advantage is that through the different operational modes, the total antenna volume can be reused, and therefore the overall antenna can be made compact. In these designs, the selection of the different modes is achieved by either i) switching different feeding locations of the antenna (switched feed) or ii) switching or breaking of the antenna's connection to the ground (switched ground). This paper demonstrates these two designs. For the first design of switched feed, it can support GSM, DCS, PCS, and UMTS. In the second design, the antenna makes use of a switched-ground technique, which can cover GSM,DCS, PCS, UMTS, Bluetooth, and 2.4 GHz wireless LAN. The designs are investigated when ideal switches and also various realistic active switches based on PIN diodes, GaAs field effect transistor, and MEMs configurations. The designs are verified through both numerical simulations and measurement of an experimental prototype. The results confirm good performance of the two multiband reconfigurable antenna designs. Index Terms--Planar inverted F-antenna (PIFA), reconfigurable antennas, volume reuse, wireless communications.

A simple ground plane structure that can reduce mutual coupling between closely-packed antenna elements is proposed and studied. The structure consists of a slitted pattern, without via's, etched onto a single ground plane and it is therefore low cost and straightforward to fabricate. It is found that isolations of more than -20 dB can be achieved between two parallel individual planar inverted-F antennas (PIFAs) sharing a common ground plane, with inter-antenna spacing (center to center) of 0.116 [[lambda].sub.o] and ground plane size 0.331 [[lambda].sup.2.sub.o]. At 2.31 GHz it is demonstrated that this translates into an edge to edge separation between antennas of just 10 mm. Similarly the structure can be applied to reduce mutual coupling between three or four radiating elements. In addition the mutual coupling between half wavelength patches and monopoles can also be reduced with the aid of the proposed ground plane structure. Results of parametric studies are also given in this paper. Both simulation and measurement results are used to confirm the suppression of mutual coupling between closely-packed antenna elements with our slitted ground plane. Index Terms--Monopole antennas, multiple input multiple output (MIMO), mutual coupling, patch antennas, PIFAs.

Research has been conducted on the biosynthesis of the nonadride CP-225,917. Experiments include the dimerization of the C (sub)16 anhydride from the lauric and oxaloacetic acids condensation.

A capacitively loaded planar inverted-F antenna (PIFA) is proposed and studied. It is found that the capacitive load reduces the resonance length of the PIFA from [Lambda]/4 to less than [Lambda]/8. A design with a bandwidth of 178 MHz centered at 1.8 GHz is provided to demonstrate that compact antennas for mobile telephone handsets can be constructed using this approach. The finite-difference time-domain (FDTD) method is used in the study and experimental verification is also provided. Index Terms - FDTD methods, mobile antennas.

Planar inverted F antennas (PIFA) have been proposed as possible candidates for mobile telephone handsets. In this letter, we describe the design of a compact PIFA suitable for operation at 900 MHz. In addition, we provide modifications to this design that allow it to operate in dual-frequency bands at 900 and 1800 MHz. Finite-difference time-domain (FDTD) and experimental results are provided. Index Terms - Antennas, mobile communication.

High-frame-rate (HFR) ultrasound (US) imaging and contrast-enhanced US (CEUS) are often implemented using multipulse transmissions, to enhance image quality. Multipulse approaches, however, suffer from degradation in the presence of motion, especially when coherent compounding and CEUS are combined. In this paper, we investigate this effect on the intensity of HFR CEUS in deep tissue imaging using simulations and in vivo contrast echocardiography (CE). The simulation results show that the motion artifact is much higher when the flow is in an axial direction than a lateral direction. Using a pulse repetition frequency suitable for cardiac imaging, a motion of 35 cm/s can cause as much as 28.5 dB decrease in image intensity, where compounding can contribute up to 18.7 dB of intensity decrease (11 angles). These motion effects are also demonstrated for in vivo cardiac HFR CE, where the large velocities of both the myocardium and the blood are present. Intensity reductions of 10.4 dB are readily visible in the chamber. Finally, we demonstrate how performing motion–correction before pulse inversion compounding greatly reduces such motion artifact and improve image signal-to-noise ratio and contrast. [ABSTRACT FROM AUTHOR]

Arterio-Venous Fistulae (AVF) are regarded as the "gold standard" method of vascular access for patients with end-stage renal disease who require haemodialysis. However, a large proportion of AVF do not mature, and hence fail, as a result of various pathologies such as Intimal Hyperplasia (IH). Unphysiological flow patterns, including high-frequency flow unsteadiness, associated with the unnatural and often complex geometries of AVF are believed to be implicated in the development of IH. In the present study, we employ a Mesh Adaptive Direct Search optimisation framework, computational fluid dynamics simulations, and a new cost function to design a novel non-planar AVF configuration that can suppress high-frequency unsteady flow. A prototype device for holding an AVF in the optimal configuration is then fabricated, and proof-of-concept is demonstrated in a porcine model. Results constitute the first use of numerical optimisation to design a device for suppressing potentially pathological high-frequency flow unsteadiness in AVF. [ABSTRACT FROM AUTHOR]

The first total synthesis and tentative stereochemical assignment of (+)-zampanolide is presented. Key elements of synthesis include efficient use of Petasis-Ferrier rearrangement to construct cis-2,6-disubstistuted tetrahydropyran and a stereospecific Curtius rearrangement to set stereogenicity.

This paper presents a novel method using multiple compact antenna test range (CATR) reflectors to perform simultaneous multiple angle measurements for 5G devices that are capable of beam-forming in the millimeter wave frequency range. Four CATR reflectors and their respective feed antennas are arranged on a planar semi-circle arc with the device under test placed on a positioner at the center of the arc. This arrangement is designed to generate four planar wavefronts with different incidences, realizing up to five pairs of angular spreads or four switched/simultaneous angles of arrival. The objective of this setup is to reproduce configurations involving multiple base-stations radiating from different directions. The initial target application is radio resource management (RRM) testing, where the execution of mobility procedures and radio link monitoring of a 5G millimeter wave device are evaluated. The reflectors create far-field conditions at the device under test for quiet zones up to 30 cm in diameter inside a portable system with a footprint of 3.25 × 1.4 meters. The applicability of the approach to RRM testing is demonstrated through measurements, performed with both sinusoidal and modulated signals, using horn antennas and commercial 5G devices.

Arterio-Venous Fistulae (AVF) are the preferred method of vascular access for patients with end stage renal disease who need hemodialysis. In this study, simulations of blood flow and oxygen transport were undertaken in various idealized AVF configurations. The objective of the study was to understand how arterial curvature affects blood flow and oxygen transport patterns within AVF, with a focus on how curvature alters metrics known to correlate with vascular pathology such as Intimal Hyperplasia (IH). If one subscribes to the hypothesis that unsteady flow causes IH within AVF, then the results suggest that in order to avoid IH, AVF should be formed via a vein graft onto the outer-curvature of a curved artery. However, if one subscribes to the hypothesis that low wall shear stress and/or low lumen-to-wall oxygen flux (leading to wall hypoxia) cause IH within AVF, then the results suggest that in order to avoid IH, AVF should be formed via a vein graft onto a straight artery, or the inner-curvature of a curved artery. We note that the recommendations are incompatible--highlighting the importance of ascertaining the exact mechanisms underlying development of IH in AVF. Nonetheless, the results clearly illustrate the important role played by arterial curvature in determining AVF hemodynamics, which to our knowledge has been overlooked in all previous studies. [ABSTRACT FROM AUTHOR]

An efficient synthetic route to the potent and selective ErbB VEGF receptor inhibitor, BMS-690514 (1) is described. Strategic modifications in both approach and procedure addressed several issues, which led to a safe, efficient, and economical process for the preparation of multi-kilogram quantities of 1. The convergent route involves alkylation of a suitably protected (3R,4R)-4-aminopiperidin-3-ol with the triethyl(alkyl)ammonium salt of a functionalized pyrrolotriazine 3a followed by deprotection to provide 1 as the crystalline free base. [ABSTRACT FROM AUTHOR]

A high performance gel imaging system was constructed using a digital single lens reflex camera with epi-illumination to image 19 × 23 cm agarose gels with up to 10,000 DNA bands each. It was found to give equivalent performance to a laser scanner in this high throughput DNA fingerprinting application using the fluorophore SYBR Green®. The specificity and sensitivity of the imager and scanner were within 1% using the same band identification software. Low and high cost color filters were also compared and it was found that with care, good results could be obtained with inexpensive dyed acrylic filters in combination with more costly dielectric interference filters, but that very poor combinations were also possible. Methods for determining resolution, dynamic range, and optical efficiency for imagers are also proposed to facilitate comparison between systems. [ABSTRACT FROM AUTHOR]

Introduction: The diurnal rhythm of saliva cortisol and its association to adaptation, performance and health were examined in personnel over-wintering at two British Antarctic stations. Methods: In total, 55 healthy individuals (49 males, 6 females) participated in the study. Cortisol in saliva was sampled on 3 consecutive days (at awakening, 15 and 45 min after waking, at 15.00 h, and 22.00 h) immediately after arrival at the station, midwinter, and the last week before departure. Subjective health complaints were also measured at arrival, midwinter, and the last week before departure, while depression (Burnam screen for depression) and positive and negative affect (PANAS) were measured at midwinter only. At the end of the winter appointment, base commanders evaluated the performance of all personnel. Results: The variations in external light (darkness during winter, midnight sun during arrival and departure) did not influence the diurnal rhythms. The normal peak level in the morning, and the normal and gradual fall towards the evening were observed at arrival, midwinter, and before departure. Immediately after arrival the cortisol values were relatively high and correlated positively with base commander's evaluation of performance. During midwinter, approximately 58% scored for depression on the Burnam scale. However, when examining these data more closely, only 4 participants (7%) reported depression, the main reason for the high score on the depression scale was related to sleep problems and tiredness. Conclusions: There was no indication that over-wintering led to any disturbance in the diurnal rhythm of cortisol in British Antarctic personnel. There were no other indications of any 'over-wintering syndrome' than reports of subjective sleep problems and tiredness. [ABSTRACT FROM AUTHOR]

This paper reviews some of the issues connected with questions of ethics, health economics, radiation dose and referral criteria arising from a workshop held under the auspices of the Sentinel Research Program FP6-012909. An extensive bibliography of further reading is included. [ABSTRACT FROM AUTHOR]

In interventional cardiac procedures, staff operates near the patient in a non-uniformly scattered radiation field. Consequently, workers may receive, over a period, relatively high radiation doses. The measurement of individual doses to personnel becomes critical due to the use of protective devices and, as a consequence of the large number of methods proposed to assess the effective dose, great variability in monitoring programmes is expected among European countries. SENTINEL consortium has conducted a survey on staff dosimetry methods and on the level of staff exposure in 12 European cardiac centres demonstrating the urgent need to harmonise dosimetry methods. From the dosimetry survey, constraint annual effective dose of 1.4 mSv and Hp(0.07) over the protective apron of 14 mSv are proposed for the optimisation the exposure the most-exposed operator. [ABSTRACT FROM AUTHOR]

Abstract: Barley grain is one of the most common feed grains used in diets for dairy and beef cattle. Because the endosperm of the barley kernel is surrounded by the pericarp, which is extremely resistant to microbial degradation in the rumen, dry barley grain needs to be processed to improve its utilization by beef and dairy cattle. Dry rolling is a common processing method, and increases ruminal digestibility of grain and productivity of animals, but the grain kernels often shatter during processing, producing many fine particles, which has been associated with inconsistent animal performance. Steam rolling and temper rolling can reduce production of fine particles during rolling, allowing more uniform particle size distribution. Steam flaking uses moisture, heat and pressure to gelatinize starch granules, but positive effects of starch gelatinization on animal performance may be less for barley grain versus corn or sorghum because barley starch, once exposed to microbial organisms in the rumen, is readily degradable even without being gelatinized. Treatment of grains with NaOH may increase its ruminal starch digestibility without increasing ruminal rate of starch release. Roasting and aldehyde treatment decrease the rate of crude protein degradation and optimize organic matter degradation in the rumen, while application of ammonia or fibrolytic enzymes can increase degradation of the hull. Consistency in processed grain quality (e.g., particle size) and predictability in animal performance should be considered as an important quality parameter of processing. In addition, initial grain quality, extent of processing, processing method, and their interactions, determine the feeding value of barley grain and affect the productivity of cattle. Further research is warranted to develop a common quality parameter accounting for variations in physical, chemical and biochemical properties for processed barley grain. [Copyright &y& Elsevier]