Defining and quantifying microscale wave breaking with infrared imagery

Breaking without air entrainment of very short wind-forced waves, or microscale wave breaking, is undoubtedly widespread over the oceans and may prove to be a significant mechanism for enhancing the transfer of heat and gas across the air-sea interface. However, quantifying the effects of microscale wave breaking has been difficult because the phenomenon lacks the visible manifestation of whitecapping. In this brief report we present limited but promising laboratory measurements which show that microscale wave breaking associated with evolving wind waves disturbs the thermal boundary layer at the air-water interface, producing signatures that can be detected with infrared imagery. Simultaneous video and infrared observations show that the infrared signature itself may serve as a practical means of defining and characterizing the microscale breaking process. The infrared imagery is used to quantify microscale breaking waves in terms of the frequency of occurrence and the areal coverage, which is substantial under the moderate wind speed conditions investigated. The results imply that ”bursting“ phenomena observed beneath laboratory wind waves are likely produced by microscale breaking waves but that not all microscale breaking waves produce bursts. Oceanic measurements show the ability to quantify microscale wave breaking in the field. Our results demonstrate that infrared techniques can provide the information necessary to quantify the breaking process for inclusion in models of air-sea heat and gas fluxes, as well as unprecedented details on the origin and evolution of microscale wave breaking

What do you need? 2007-08 findings from a national survey of people with diagnosed HIV

Over the past twenty-five years, both the needs of people with diagnosed HIV and our understanding of them have changed dramatically. During this time there have been many assessments of need, usually within specific geographic boundaries (such as Primary Care Trusts) but no consistent approach to describing needs has been adopted. Most needs assessments have been shaped by a variety of local factors, including the profile of existing services. This study provides an insight into the needs of people with diagnosed HIV living in the UK, based on a final sample of 1777 people. The approach taken to measuring and describing need is the same as our previous national survey (Weatherburn et al. 2002). This approach was shaped by our earlier qualitative studies exploring the experience of people with diagnosed HIV in the early days of anti-HIV treatments (Anderson et al. 2000, Anderson & Weatherburn 1999, Anderson & Weatherburn 1998). While this study uses the same methods as our 2001-2002 survey we do not draw direct comparisons with our previous data or discuss change over time. The limitations of self-completion surveys using convenience samples make change comparisons hazardous. However, it is worth noting that in any comparison with our prior data (Weatherburn et al. 2002) current levels of need very rarely seem lower than we have previously reported. The range and extent of medical and social care, support and information needs we present here reveal significant challenges for service commissioners and providers. The first challenge is to avoid drawing quick conclusions about what the patterns of need mean for service commissioning and delivery. Needs have deliberately been separated from service use because the question of what services are ‘needed’ cannot be answered simply by identifying the extent of personal needs. The overall pattern of need is a useful starting point, but this pattern is complex

The Pentameric Vertex Proteins Are Necessary for the Icosahedral Carboxysome Shell to Function as a CO\u3csub\u3e2\u3c/sub\u3e Leakage Barrier

Background Carboxysomes are polyhedral protein microcompartments found in many autotrophic bacteria; they encapsulate the CO2 fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) within a thin protein shell and provide an environment that enhances the catalytic capabilities of the enzyme. Two types of shell protein constituents are common to carboxysomes and related microcompartments of heterotrophic bacteria, and the genes for these proteins are found in a large variety of bacteria. Methodology/Principal Findings We have created a Halothiobacillus neapolitanus knockout mutant that does not produce the two paralogous CsoS4 proteins thought to occupy the vertices of the icosahedral carboxysomes and related microcompartments. Biochemical and ultrastructural analyses indicated that the mutant predominantly forms carboxysomes of normal appearance, in addition to some elongated microcompartments. Despite their normal shape, purified mutant carboxysomes are functionally impaired, although the activities of the encapsulated enzymes are not negatively affected. Conclusions/Significance In the absence of the CsoS4 proteins the carboxysome shell loses its limited permeability to CO2 and is no longer able to provide the catalytic advantage RubisCO derives from microcompartmentalization. This study presents direct evidence that the diffusion barrier property of the carboxysome shell contributes significantly to the biological function of the carboxysome

Miocene paleoaltimetry of the Mt. Everest region

Abstract HKT-ISTP 2013 A

Use of low-pressure storage to improve the quality of tomatoes

Freshly harvested vine-ripened tomatoes (Solanum lycopersicum cv. Neang Pich) were stored at low pressure (4 kPa) at 10°C for 11 days with 100% RH. Fruit quality was examined upon removal and after being transferred to normal atmosphere (101 kPa) at 20°C for 3 days. Weight loss was significantly lower in fruits which were stored at low pressure (4 kPa) than in fruits that were stored at regular atmosphere (101 kPa) at 10°C. Fruits that were stored at low pressure (4 kPa) reduced calyx browning by 12.5%, and calyx rots by 16%, compared to fruits that were stored at regular atmosphere (101 kPa) at 10°C. Fruit firmness was not significantly different between fruits stored at low pressures (4 kPa) and the normal atmosphere (101 kPa), with an average firmness of 14 N after fruits were stored at 10°C for 11 days. There was no difference in the SSC/TA ratio. The results suggest that a low pressure of 4 kPa at 10°C has potential as an alternative, non-chemical postharvest treatment to improve tomato quality during storage

Negotiation in strategy making teams : group support systems and the process of cognitive change

This paper reports on the use of a Group Support System (GSS) to explore at a micro level some of the processes manifested when a group is negotiating strategy-processes of social and psychological negotiation. It is based on data from a series of interventions with senior management teams of three operating companies comprising a multi-national organization, and with a joint meeting subsequently involving all of the previous participants. The meetings were concerned with negotiating a new strategy for the global organization. The research involved the analysis of detailed time series data logs that exist as a result of using a GSS that is a reflection of cognitive theory

Plus One: HIV diagnosis and disclosure

Plus One: HIV sero-discordant relationships among black African people in England (NAHIP) Duration: September 2010 - November 2011 Plus One involved in-depth, face-to-face interviews with black African people living in England who were in relationships where one person had diagnosed HIV and the other did not (ie. HIV serodiscordant)