A study of ablation effects on antenna performance Final report, 7 Jul. 1965 - 12 Oct. 1966

Dielectric property screening tests, and temperature range tests for determining ablation material effects on Apollo model antennas - simulation of thermal protection syste

Compositional changes in ripening grapes: Caftaric and coutaric acids

Caftaric and coutaric acid contents (juice concentration, amounts per berry, percent of the cis forms) were investigated in samples fully protected from oxidation as ripeness increased in harvests from Grenache, French Colombard and two harvests from different vineyards of Ruby Cabernet Vitis vinifera grapes. Segregation by berry density gave sugar content (ripeness) sequences· free of other variables such as weather and provided berries of nearly identical °Brix at each ripeness level. The two Ruby Cabernet harvests, even though differing considerably in growing conditions and average °Brix level, were much closer in the details of caftaric and coutaric acid compositions to each other than to the other varieties indicating close genetic (varietal) control of these components. The proportion of coutaric to caftaric and the percentage of cis forms tend to rise toward the end of ripening. The overall ripening pattern appears to be that these components are synthesized as the berry enlarges during ripening. If the rate of synthesis is able to keep up with the berry enlargement and the content moderate (French Colombard, Ruby Cabernet), the concentration in juice stays nearly constant at a level typical for the variety. If the content is high (Grenache) and the synthesis does not keep up with berry enlargement, the concentration in juice falls as the berry content rises during ripening, but a relatively high concentration is maintained. Overripe, shriveling berries rise in concentration, but may lose caftaric acid by oxidation if tissue breakdown occurs

Caftaric acid in grapes and conversion to a reaction product during processing

Grapes were crushed in the presence of high levels of the anti-oxidants SO2 and ascorbic acid, in an atmosphere deprived of oxygen. Hydroxycinnamic derivatives, particularly caftaric acid in the grape juice were found in much higher amounts than when the usual processing methods were employed.Partial oxidation of caftaric acid is not only very rapid and extensive during unprotected grflpe crushing and juice separation but gives a major reaction product that behaves as a single entity and survives through vinification. It gives a sharp HPLC peak and behaves reciprocally with caftaric, i.e., when caftaric acid in must remains high relative to the berry content the reaction product is low and vice versa. The product appeared identical in all grape varieties tested.The reaction product is about one-sixth as extractable by immiscible solvents as is the parent caftaric acid. It can constitute a large part of the 320 nm absorbance of a wine and explains the variable results and poor yields in attempts to isolate caftaric acid from ordinary wine or juice.L'acide caftarique des raisins et sa conversion en produit de réaction au cours de la vinificationA l'aide de HPLC il a été mis en évidence que l'acide caftarique (caffeoyl tartrique) subit des pertes rapides lors du foulage des raisins dans le cas où ceux-ci ne sont pas complètement protégés contre l'oxidation, comme par ex. foulage en atmosphère inerte en présence d'un niveau élevé de métabisulfite de potassium et d'acide ascorbique. En l'absence de telles précautions les valeurs de la teneur originelle en acide caftarique, considérées comme étant caractéristiques des variétés de vigne, sont douteuses. Des échantillons totalement protégés de 5 variétés blanches et 3 variétés rouges de Vitis vinifera, mûres, se rangent entre 200 mg/l de jus pour Grenache et 50 mg/l pour Carignane. Dans la mesure que l'exposition à l'oxygène et l'activité de phénolase sont évaluables la perte peut être importante. Une majeure partie de cette perte consiste dans un produit de réaction de l'acide caftarique ici pour la première fois décelé (CRP). Ce CRP peut pénétrer dans le vin et sa détermination par HPLC ainsi que celle de l'acide caftarique non transformé montrent, en fonction de la variété de vigne, une grande conversion au cours de la préparation normale du moût. De telles analyses de vins peuvent servir d'indicateurs de l'exposition à l'oxygène au cours de la préparation du moût. La nature du CRP est actuellement étudiée et sa présence peut contribuer à expliquer la faible récupération de l'acide caftarique du moût ou du vin

Patient-reported outcomes of periacetabular osteotomy from the prospective ANCHOR cohort study

BACKGROUND: Current literature describing the periacetabular osteotomy (PAO) is mostly limited to retrospective case series. Larger, prospective cohort studies are needed to provide better clinical evidence regarding this procedure. The goals of the current study were to (1) report minimum 2-year patient-reported outcomes (pain, hip function, activity, overall health, and quality of life), (2) investigate preoperative clinical and disease characteristics as predictors of clinical outcomes, and (3) report the rate of early failures and reoperations in patients undergoing contemporary PAO surgery. METHODS: A large, prospective, multicenter cohort of PAO procedures was established, and outcomes at a minimum of 2 years were analyzed. A total of 391 hips were included for analysis (79% of the patients were female, and the average patient age was 25.4 years). Patient-reported outcomes, conversion to total hip replacement, reoperations, and major complications were documented. Variables with a p value of ≤0.10 in the univariate linear regressions were included in the multivariate linear regression. The backward stepwise selection method was used to determine the final risk factors of clinical outcomes. RESULTS: Clinical outcome analysis demonstrated major clinically important improvements in pain, function, quality of life, overall health, and activity level. Increasing age and a body mass index status of overweight or obese were predictive of improved results for certain outcome metrics. Male sex and mild acetabular dysplasia were predictive of lesser improvements in certain outcome measures. Three (0.8%) of the hips underwent early conversion to total hip arthroplasty, 12 (3%) required reoperation, and 26 (7%) experienced a major complication. CONCLUSIONS: This large, prospective cohort study demonstrated the clinical success of contemporary PAO surgery for the treatment of symptomatic acetabular dysplasia. Patient and disease characteristics demonstrated predictive value that should be considered in surgical decision-making. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence

What questions do patients undergoing lower extremity joint replacement surgery have?

BACKGROUND: The value of the Internet to deliver preoperative education would increase if there was variability in questions patients want answered. This study's goal was to have patients consulting an orthopedic surgeon about undergoing either a total hip arthroplasty (THA) or a total knee arthroplasty (TKA) rate the importance of different questions concerning their care. METHODS: We assembled questions patients might have about joint replacement surgery by analyzing the literature and querying a pilot group of patients and surgeons. Twenty-nine patients considering undergoing THA and 19 patients considering TKR completed a written survey asking them to rate 30 different questions, with a 5 point Likert scale from 1 (least important) – 5 (most important). RESULTS: For patients considering THA or TKR, the 4 highest rated questions were: Will the surgery affect my abilities to care for myself?, Am I going to need physical therapy?, How mobile will I be after my surgery?, When will I be able to walk normally again? The mean percentage disagreement was 42% for questions answered by TKR patients and 47% for the THA group. Some patients gave a high rating to questions lowly rated by the rest of the group. CONCLUSIONS: Although there was enough agreement to define a core set of questions that should be addressed with most patients considering THA or TKA, some of the remaining questions were also highly important to some patients. The Web may offer a flexible medium for accommodating this large variety of information needs

The uses and abuses of power: teaching school leadership through children's literature

There are relatively few studies of how representations of teachers, schools and educational administrators in popular films and television might be, and are, used in leadership preparation. This paper seeks to add to this small body of work; it reports on an exploratory study of the representation of headteachers in contemporary children's fiction. Thirty-one texts are analysed to ascertain key themes and the major characterisations. The paper draws on children's literature scholars to argue that both the historical school story and its contemporary counterpart focus heavily on the power of the head to control the micro-world of the school. Because these fictional accounts deal with issues of power and justice more openly than many mainstream educational administration texts, this makes them particularly useful in the preparation of potential school leaders

Impact of network structure and cellular response on spike time correlations

Novel experimental techniques reveal the simultaneous activity of larger and larger numbers of neurons. As a result there is increasing interest in the structure of cooperative -- or correlated -- activity in neural populations, and in the possible impact of such correlations on the neural code. A fundamental theoretical challenge is to understand how the architecture of network connectivity along with the dynamical properties of single cells shape the magnitude and timescale of correlations. We provide a general approach to this problem by extending prior techniques based on linear response theory. We consider networks of general integrate-and-fire cells with arbitrary architecture, and provide explicit expressions for the approximate cross-correlation between constituent cells. These correlations depend strongly on the operating point (input mean and variance) of the neurons, even when connectivity is fixed. Moreover, the approximations admit an expansion in powers of the matrices that describe the network architecture. This expansion can be readily interpreted in terms of paths between different cells. We apply our results to large excitatory-inhibitory networks, and demonstrate first how precise balance --- or lack thereof --- between the strengths and timescales of excitatory and inhibitory synapses is reflected in the overall correlation structure of the network. We then derive explicit expressions for the average correlation structure in randomly connected networks. These expressions help to identify the important factors that shape coordinated neural activity in such networks