Risk assessments are fundamental to invasive species management and are underpinned by comprehensive characterization of invasive species impacts. Our understanding of the impacts of invasive species is growing constantly, and several recently developed frameworks offer the opportunity to systematically categorize environmental and socioeconomic impacts of invasive species. Invasive ants are among the most widespread and damaging invaders.
View Article and Find Full Text PDFIdentification of factors associated with the quality and quantity of colostrum production has always been a major challenge in cattle industry. In purebred double-muscled Belgian Blue (BB) cows, parturition is mainly performed by elective caesarean section (CS; >90%). However, the CS itself may influence colostrum production characteristics.
View Article and Find Full Text PDFThe increased exportation of semen and embryos of double-muscled beef breeds to tropical and developing countries makes it important to investigate the reproductive capacity of these breeds in adapting to tropical conditions. The aim of this study was to evaluate the quality of Belgian Blue semen collected after there is heat-stress (HS; as a mimic of tropical condition) compared with non-heat stressed (NHS; as their comfort zone), using practical spermatozoa staining methods such that prevail in developing countries. There was screening of semen kinetics using CASA and evaluation of their DNA-, acrosome, plasma membrane-integrity, and mitochondrial activity.
View Article and Find Full Text PDFA widely held assumption in ecology is that specialists are more efficient than generalists. However, empirical evidence for this fundamental assumption is surprisingly scarce and often contradictory. Theoretically, the evolution of alternative life history strategies is underpinned by a trade-off between activity levels and survival.
View Article and Find Full Text PDFSkin sodium (Na(+) ) storage, as a physiologically important regulatory mechanism for blood pressure, volume regulation and, indeed, survival, has recently been rediscovered. This has prompted the development of MRI methods to assess Na(+) storage in humans ((23) Na MRI) at 3.0 T.
View Article and Find Full Text PDFObjectives: This study was designed to examine the feasibility of ophthalmic magnetic resonance imaging (MRI) at 7 T using a local 6-channel transmit/receive radiofrequency (RF) coil array in healthy volunteers and patients with intraocular masses.
Materials And Methods: A novel 6-element transceiver RF coil array that makes uses of loop elements and that is customized for eye imaging at 7 T is proposed. Considerations influencing the RF coil design and the characteristics of the proposed RF coil array are presented.
Introduction: Visual but subjective reading of longitudinal relaxation time (T1) weighted magnetic resonance images is commonly used for the detection of brain pathologies. For this non-quantitative measure, diagnostic quality depends on hardware configuration, imaging parameters, radio frequency transmission field (B1+) uniformity, as well as observer experience. Parametric quantification of the tissue T1 relaxation parameter offsets the propensity for these effects, but is typically time consuming.
View Article and Find Full Text PDFPurpose: To design and evaluate a modular transceiver coil array with 32 independent channels for cardiac MRI at 7.0T.
Methods: The modular coil array comprises eight independent building blocks, each containing four transceiver loop elements.
This work demonstrates the feasibility of a hybrid radiofrequency (RF) applicator that supports magnetic resonance (MR) imaging and MR controlled targeted RF heating at ultrahigh magnetic fields (B0≥7.0T). For this purpose a virtual and an experimental configuration of an 8-channel transmit/receive (TX/RX) hybrid RF applicator was designed.
View Article and Find Full Text PDFKnowledge of the transmission field (B1(+)) of radio-frequency coils is crucial for high field (B0 = 3.0 T) and ultrahigh field (B0 ≥7.0 T) magnetic resonance applications to overcome constraints dictated by electrodynamics in the short wavelength regime with the ultimate goal to improve the image quality.
View Article and Find Full Text PDFA growing number of reports eloquently speak about explorations into cardiac magnetic resonance (CMR) at ultrahigh magnetic fields (B0≥7.0 T). Realizing the progress, promises and challenges of ultrahigh field (UHF) CMR this perspective outlines current trends in enabling MR technology tailored for cardiac MR in the short wavelength regime.
View Article and Find Full Text PDFThe sensitivity gain of ultrahigh field Magnetic Resonance (UHF-MR) holds the promise to enhance spatial and temporal resolution. Such improvements could be beneficial for cardiovascular MR. However, intracoronary stents used for treatment of coronary artery disease are currently considered to be contra-indications for UHF-MR.
View Article and Find Full Text PDFHypertension is linked to disturbed total-body sodium (Na(+)) regulation; however, measuring Na(+) disposition in the body is difficult. We implemented (23)Na magnetic resonance spectroscopy ((23)Na-MR) and imaging technique ((23)Na-MRI) at 9.4T for animals and 3T for humans to quantify Na(+) content in skeletal muscle and skin.
View Article and Find Full Text PDF1. Individual foraging behaviour defines the use of resources by a given population and its variation in different ways such as, for example, unpredictable interactions between taxon-biased and size-biased selection. Here we investigated how the environmental availability of prey and individual specialization, for both prey taxa and prey size, shape niche variation across generations in the grasshopper-hunting digger wasp Stizus continuus.
View Article and Find Full Text PDFA novel method is presented for the three-dimensional mapping of the B(1) -field of a transmit radio-frequency MR coil. The method is based on the acquisition of phase images, where the effective flip angle is encoded in the phase of the nonselective hard pulse excitation. The method involves the application of a rectangular composite pulse as excitation in a three-dimensional gradient recall echo to produce measurable phase angle variation.
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