Flavonol haze in white wines

The formation of a yellow haze in commercial white wines, and of yellow sediments from both juices and wines, was due to precipitation of quercetin. The vine leaves were found to be the major source of soluble quercetin glycosides, leading to excessive levels of free quercetin after hydrolysis during juice or wine storage. Flavonols were analysed by reversed-phase HPLC. Widespread use of machine harvesting, with higher leaf contamination of the grape crush, is considered to be the primary cause of this new form of wine instability. An enzymatic procedure for detecting susceptibility to such deposition in juices and wines is described

Evolution of red wines II. An assessment of the role of acetaldehyde

Factors influencing formation and utilisation of acetaldehyde during red vinification have been examined, with emphasis on its production during primary fermentation and depletfon during early maturation.Acetaldehyde concentrations in new wines were controlled at predictably low levels by addition of SO2 at 30- 50 mg/l before fermentation. There was no appreciable effect from yeast strain, pH or temperature on acetaldehyde production. Significant decrease in acetaldehyde, a-ketoglutaric acid and pyruvic acid, with release of free SO2, occurred during malolactic fermentation. The rate of acetaldehyde consumption in sterile-filtered wine was increased at higher te·mperature and decreased by the presence of free SO2 at high levels. Progressive change in pigment composition of new wines was not influenced by variation in bound acetaldehyde within the range 2-103 mg/l.Acetaldehyde concentration also decreased in a majority of red wines during conservation in commercial cellars. Increases were attributed to abnormal conditions of wine exposure to air. lt was concluded that acetaldehyde formation in wine is probably a surface phenomenon, involving autoxidation of ethanol at the wine interface with atmospheric oxygen. Increase in acetaldehyde during vinification was considered to be adverse in relation to sensory properties and stability of red wine

Experimental and numerical analyses of liquid and spray penetration under heavy-duty diesel engine conditions

The modeling of fuel sprays under well-characterized conditions relevant for heavy-duty Diesel engine applications, allows for detailed analyses of individual phenomena aimed at improving emission formation and fuel consumption. However, the complexity of a reacting fuel spray under heavy-duty conditions currently prohibits direct simulation. Using a systematic approach, we extrapolate available spray models to the desired conditions without inclusion of chemical reactions. For validation, experimental techniques are utilized to characterize inert sprays of n-dodecane in a high-pressure, high-temperature (900 K) constant volume vessel with full optical access. The liquid fuel spray is studied using high-speed diffused back-illumination for conditions with different densities (22.8 and 40 kg/m3) and injection pressures (150, 80 and 160 MPa), using a 0.205-mm orifice diameter nozzle. High-speed Schlieren imaging is used to analyze the influence of these boundary conditions on the spray penetration. Simulations of the fuel spray are performed using a dedicated computational mesh with refinements at the known location of the jet to capture the smallest scales of interest. Using a blob injection model refined with a primary atomization and secondary breakup model, correct trends and good agreement are achieved for both liquid and spray penetration. The capability of capturing the trends at largely varying boundary conditions with a single computational approach provides a solid base for future work

HIV risk among Australian men travelling overseas: networks and context matter

Increasing international mobility presents a risk for communicable disease transmissions. Overseas-acquired HIV infections have been increasingly observed across Australian jurisdictions. This includes a mix of men emigrating from countries with high HIV prevalence and men travelling abroad. There is currently little research exploring international mobility and HIV risk and as a consequence the increase of men acquiring HIV while travelling overseas is poorly understood. This article draws on data from a qualitative study exploring the risk perspectives and experiences of 14 Australian men who acquired HIV while travelling overseas in the years between 2000-2009. Participants articulated a strong desire to distance themselves from the identity of a tourist. Social networks were highlighted as important entry points to engage with other foreign travellers and expatriates. These networks were highly influential and were understood by the participants to provide guidance on how they should negotiate the local scene, including where to meet sex partners. Limited discussion of safe sex and HIV was mentioned in these contexts. The findings suggest that prevalent social norms and social networks play an influential role in how participants negotiate sex and social relations in overseas settings. These networks could potentially provide sites for effective HIV prevention programs. Keywords: male tourists; HIV transmission; social networks; behaviour; sexual risk; HIV preventio

A Countermeasure for Space Motion Sickness

Overall, the results obtained in both the U.S. and the Russian space programs indicate that most space crews will experience some symptoms of motion sickness (MS) causing significant impact on the operational objectives that must be accomplished to assure mission success. At this time the primary countermeasure for MS requires the administration of Promethazine. Promethazine is not a benign drug, and is most frequently administered just prior to the sleep cycle to prevent its side effects from further compromising mission objectives. Clearly other countermeasures for SMS must be developed. Currently the primary focus is on two different technologies: (1) developing new and different pharmacological compounds with less significant side effects, (2) preflight training. The primary problem with all of these methods for controlling MS is time. New drugs that may be beneficial are years from testing and development, and preflight training requires a significant investment of crew time during an already intensive pre-launch schedule. Granted, motion sickness symptoms can be minimized with either of the two methods detailed above, however, it may be possible to develop a countermeasure that does not require either extensive adaptation time or exposure to motion sickness. Approximately 25 years ago Professor Geoffrey Melvill Jones presented his work on adaptation of the vestibuloocular reflex (VOR) using optically reversed vision (left-right prisms) during head rotations in the horizontal plane. It was of no surprise that most subjects experienced motion sickness while wearing the optically reversing prisms. However, a serendipitous finding emerged during this research showing that the same subjects did not experience motion sickness symptoms when wearing the reversing prisms under stroboscopic illumination. The mechanism, by which this side-effect was believed to have occurred, is not clearly understood. However, the fact that no motion sickness was ever noted, suggests the possibility of producing functionally useful adaptation during space flight without the penalty of disabling motion sickness by controlling the rate of the adaptive process by means of an appropriate stroboscopically presented environment. After several recent meetings with Professor Melvill Jones, we were encouraged to repeat the motion sickness portions of his and Mandl's 1981 stroboscopic experiment. In conducting this experiment we used a randomized cross-over design where subjects were randomly assigned to either a stroboscopic flash or no strobe for their first exposure in the experimental design. Twenty subjects (19 subjects completed the study) read a short passage from Treasure Island mounted on the wall approximately 1 m from their eyes while wearing left-right reversing prisms. The strobe on time of 3 microseconds and flash frequency of 4 Hz was set to equal that used in the original study. Motion sickness was scored using a modified Miller and Graybiel scale that we constructed to include symptoms that may be elicited under conditions where reversing prisms are worn. On this scale a score of 5 represented Malaise IIa (mild motion sickness) and a score of 8 or above is approaching frank sickness. Symptoms were tracked and recorded every 5 min during the task. Testing was limited to 30 min unless the subject had reached the MIIa score, at which time the test was terminated. Performance under stroboscopic illumination was significantly better than when the subjects read under normal room illumination while wearing the left-right reversing prisms. Based on these results we developed a goggle system using LCD material that can be strobed. To evaluate the effectiveness of stroboscopic goggles we tested an additional 9 subjects in addition to retesting 10 used in the stroboscopic pilot study described above. These 19 subjects wore a pair of strobing LCD goggles that could be cycled at 4 Hz. These subjects wore the goggles while also wearing left-right reversg prisms. Results while wearing the goggles showed that none of the 19 subjects scored at the MIIa level on the motion sickness rating scale. When the goggles did not flash (no strobe), 11 of the 19 developed symptoms above the MIIa criteria. As a countermeasure the goggles seem to be effective, even with an on time of 10 msec (time the goggles are clear). We have also collected anecdotal data, from our personnel in the Neuroscience Laboratory at the Johnson Space Center, suggesting that the goggles may effective in preventing carsickness

Geriatric pharmacotherapy : optimisation through integrated approach in the hospital setting

Since older patients are more vulnerable to adverse drug-related events, there is a need to ensure appropriate prescribing in these patients in order to prevent misuse, overuse and underuse of drugs. Different tools and strategies have been developed to reduce inappropriate prescribing; the available measures can be divided into medication assessment tools, and specific interventions to reduce inappropriate prescribing. Implicit criteria of inappropriate prescribing focus on appropriate dosing, search for drug-drug interactions, and increase adherence. Explicit criteria are consensus-based standards focusing on drugs and diseases and include lists of drugs to avoid in general or lists combining drugs with clinical data. These criteria take into consideration differences between patients, and stand for a medication review, by using a systematic approach. Different types of interventions exist in order to reduce inappropriate prescribing in older patients, such as: educational interventions, computerized decision support systems, pharmacist-based interventions, and geriatric assessment. The effects of these interventions have been studied, sometimes in a multifaceted approach combining different techniques, and all types seem to have positive effects on appropriateness of prescribing. Interdisciplinary teamwork within the integrative pharmaceutical care is important for improving of outcomes and safety of drug therapy. The pharmaceutical care process consists offour steps, which are cyclic for an individual patient. These steps are pharmaceutical anamnesis, medication review, design and follow-up of a pharmaceutical care plan. A standardized approach is necessary for the adequate detection and evaluation of drug-related problems. Furthermore, it is clear that drug therapy should be reviewed in-depth, by having full access to medical records, laboratory values and nursing notes. Although clinical pharmacists perform the pharmaceutical care process to manage the patient’s drug therapy in every day clinical practice, the physician takes the ultimate responsibility for the care of the patient in close collaboration with nurses

A Form of Inherited Cerebellar Ataxia with Saccadic Intrusions, Increased Saccadic Speed, Sensory Neuropathy, and Myoclonus

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72602/1/j.1749-6632.2002.tb02850.x.pd