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Numerical modelling suggests that the turbulent boundary layer can act as an effective mountain forcing mountain waves. In the daytime, convective rolls can cover the mountains, raising the mountain-wave launching height. In non-convective conditions, the nature of the effective mountain is unknown. Here, we investigate if the early-morning boundary layer, moving rapidly across mountains, also contains large eddies of size comparable with convective cells. Temperature profiles from thousands of high-resolution radiosondes show superadiabatic gradients of vertical scale a few hundred metres in the boundary layer, appearing as the boundary-layer wind speed increases. These are explained by the overturning of potential temperature surfaces in large eddies advected with the wind and/or longitudinal rolls. An early-morning satellite image shows longitudinal rolls over mountains up to 1 km height. It is suggested that early-morning fast-moving airflow over mountains, producing mountain waves, also creates a turbulent boundary layer underneath them containing large eddies of scale a few hundred metres, in addition to classic turbulence. These are part of the effective mountain, higher than the actual mountain, which explains the formation of mountain waves. [ABSTRACT FROM AUTHOR]

Radar studies of turbulent layers have focused on Kelvin-Helmholtz instabilities caused by vertical shear of horizontal wind, also breaking gravity waves. This study examines another type of turbulent layer, common but rarely studied. Aberystwyth Meso-Strato-Troposphere ( MST) radar shows layers of turbulence where there is no unusual wind shear or breaking gravity waves. In three case studies, these layers have a common characteristic of saturated air, reducing the stability to cause possible convective or shear instability. The associated cloud may be already well-known altocumulus. Another case study using the MU radar shows how three-dimensional convective structure can be revealed using a 64-beam method. [ABSTRACT FROM AUTHOR]

We report a small molecule additive, a member of the 2-aminoimidaz-ole (2AI) group that is an analogue of the marine sponge natural prod-uct oroidin that suppresses resistance of Xanthomonas euvesicatoria to copper and decreases biofilm formation in an in vitro system. In laboratory experiments, 2AI combined with copper reduced both bacterial multiplication in broth and bacterial recovery on pepper leaf discs of a copper-resistant strain of X. euvesicatoria to a level close to that of a copper-sensitive strain. Compound 2AI used alone exhibited minimal bactericidal activity. In 3 years of field experiments, when combined with a copper-containing material, copper hydroxide (Ko-cide 3000), and other antibacterial materials, these spray mixtures resulted in decreased bacterial spot foliar disease and increased fruit yields using hybrid bell pepper (Capsicum annuum) cultivars and cop-per-resistant strains of X. euvesicatoria. This study demonstrates the concept for using small molecules as additives to antibacterial com-pounds at nonbactericidal concentrations under field conditions that, in the laboratory, were demonstrated to suppress bacterial biofilms and copper-resistant strains. [ABSTRACT FROM AUTHOR]

On occasions, laws on consent are subject to modification, largely on account of being subject to common law rather than statute--for example, in the UK. Guideline publications such as the UK Department of Health Reference Guide to Consent for Examination or Treatment are intended to provide information for clinicians on when and how to apply current laws in everyday clinical situations. While the extent to which guidelines influence clinician behaviour depends on how much they are read and followed, what is also relevant, and sometimes omitted from consideration, is discussion about underlying philosophical concepts. This paper analyses philosophical weaknesses relating to English laws on consent, the main focus of attention being applied ethics and the rights of adults with incapacity. It draws comparisons between the US and the UK, and advocates changes in English law in order to help rectify weaknesses in patient protection. Discussion includes references to Scottish law, and the use of advance directives, and it voices concerns about over-reliance on "best interests" determinations. The problem is partly one of logical analysis, and what can happen is that best interests determinations fail to show proper respect for adults lacking the capacity to consent to examination or treatment on their own behalf. This is fundamentally a matter of rights, and requires further investigation and appropriate legal remedies in order to respond to ethical deficiencies in English law as it now stands. [ABSTRACT FROM AUTHOR]

Mountain waves are observed in the free atmosphere, even when the mountain boundary layer (the source region of these waves) is neutral or convectively unstable, and filled with convective rolls, revealed by cloud streets. This paper investigates if mountain waves are caused not simply by air flow over mountain ridges, but also by flow over boundary-layer convective activity, similar to convection waves above plains and oceans. Disturbance of stable air flow above mountains by convective activity, mechanical and convective turbulence and rotors, near the ground, could move the effective mountain-wave launching height to higher than the mountain peaks. [ABSTRACT FROM AUTHOR]

In a field study on male tree lizards (Urosaurus ornatus), we tested the hypothesis that aggression is lateralized, and predicted that resident males should preferentially use the left-visual field (LVF)/right hemisphere in aggressive interactions with other males. This prediction was based on results for a small but taxonomically diverse number of vertebrates indicating a left-eye preference/ right hemisphere specialization for aggression. Many lizards use postural displays to signal aggression and lateral eye placement prevents binocular vision of such displays. The fullshow is an aggressive display that is typically performed with the body held perpendicular to that of the opponent. We staged male-male encounters by introducing stimulus males to free-ranging males (hereafter called focal males), and then recorded both the focal male’s behavior and the visual field that he used to view the intruder while performing fullshow displays. When intruders were introduced in the right visual field (RVF), focal males were equally likely to use either the LVF or RVF to perform their first fullshow. However, in these RVF introductions focal males were more likely to turn and use the LVF if the intruder was smaller. In contrast to RVF introductions, in LVF introductions focal males were significantly more likely than expected by chance to continue to use the LVF to view the intruder when performing the first fullshow. Furthermore, if focal males performed their first fullshow with the intruder in their LVF, they subsequently gave more aggressive displays than focal males that performed their first display with the intruder in their RVF. Additionally, charge (a highly aggressive behavior that usually leads to direct physical contact and a bite) was significantly more likely to occur while the LVF was being used to view the opponent. These results are consistent with the hypothesis that aggression is lateralized to the right hemisphere. This study is one of only a few examples of laterality of brain function demonstrated in a free-ranging vertebrate.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Recent radar observations of mountain waves in the troposphere and lower stratosphere above Aberystwyth (52.4°N, 4.0°W) indicate that, on average, the wave alignment is related more closely to the wind direction within the boundary layer than to the alignment of mountain ridges. This is investigated using independent data NOAA AVHRR imagery of both mountain-wave clouds and convective cloud streets, combined with surface synoptic wind measurements. The mountain-wave cloud bands are found to be aligned not at exactly 90° to the surface wind but rotated a further 18° clockwise. Similarly, in an important backup test, the cloud streets are found not to be parallel to the surface wind but rotated 12° clockwise, which agrees with over 30 years of observations, most recently of wind rows on the ocean by synthetic aperture radar (SAR). Because the wind rotates, on average, clockwise with increasing height in the northernhemisphere boundary layer, the mountain-wave clouds will be at 90° to the wind direction in the middle of the boundary layer. Therefore, the satellite images independently confirm earlier mesosphere-stratosphere-troposphere (MST) radar observations. Mountain lee waves may corrupt SAR measurements of surface wind above the ocean, so knowledge of their alignment is useful; two examples of lee waves modulating the sea roughness west of Aberystwyth are discussed. [ABSTRACT FROM AUTHOR]

Proposes a mountain wave model for mean vertical wind measured by wind-profiling radars. Mean vertical-wind profiles observed at two latitudes; Description of the proposed model; Phase relations between mountain wave clouds and the mountains below.

Mountain waves are oscillations of stable airflow over mountains which remain roughly fixed relative to the ground as the airflows through them. They are significant to numerical weather models, ozone depletion, and aviation safety. Textbook descriptions of mountain waves assume laminar flow down to the mountain surface, following the classic theory of Scorer. However, there can be a region of non-wavelike atmosphere under the mountain waves, such as convection, turbulent eddies and rotors in the boundary layer, implying a different paradigm to explain wave launching. This paper reviews how the existence of the atmosphere under the mountain waves was realised in Nazi Germany, where mountain waves were discovered using gliders in 1933 and studied in the run-up to World War 2.1 [ABSTRACT FROM AUTHOR]

The article discusses the formation of convection waves above mountains in Cross Fell, England and Wales. Several figures are provided which depict the topography and locations of Cross Fell, a satellite image of the area, and an image of the upper-level mountain-wave clouds. Also illustrated is the disappearance of the higher-wave clouds and the distribution of the boundary-layer convection.

This article presents an overview of the evolution of the incisal edge reattachment procedure. Case reports are described of patients presenting with traumatised teeth in which the reattachment procedure was performed. A review is provided of present in vivo studies detailing long-term success rates in the clinical application of this procedure. Finally, a recommended technique for diagnosis and treatment is offered to improve success in this procedure which may benefit a significant segment of the paediatric and adolescent populations. [ABSTRACT FROM AUTHOR]

Abstract: Timing and amount of solar radiation were examined as factors influencing the distribution of seven perennial plants on a small mountain located in the Chihuahuan Desert. Average direct beam solar radiation fluxes at differing times throughout the day and year were estimated with computer calculations. Principal components analysis was used to reduce the number of solar radiation parameters and include the maximum available information with a manageable number of variables. The remaining solar radiation parameters were compared to plant distributions using redundancy analysis and generalized additive models. Unimodal, bimodal, and monotonic responses were all found depending upon the species and solar radiation parameter. Niche separation at this location depends upon the timing as well as the amount of solar radiation. [Copyright &y& Elsevier]