Hybrid photocatalytic membranes embedding decatungstate for heterogeneous photooxygenation

The incorporation of decatungstate in polymeric membranes provides new heterogeneous photocatalysts for the oxidation of organic substrates under oxygen atmosphere at 25 °C. Photocatalytic membranes have been prepared yielding polymeric films with a high thermal, chemical and mechanical stability (PVDF, PDMS, Hyflon). Surface spectroscopy techniques including transmittance and reflectance UV-Vis and FT-IR have been used to assess the photocatalyst integrity within the polymeric support. Catalyst screening has been performed under both homogeneous and heterogeneous photooxygenation conditions. The photocatalyst activity has been evaluated in terms of the substrate conversion, turnover numbers, and recycling experiments. A membrane induced selectivity behavior has been evidenced by comparison with homogeneous oxidations.     

Identification of marker chromosomes and translocations in man using a computerized diagnostic database and fluorescent in situ hybridization

BACKGROUND: Many species of bats have two sets of submandibular glands, principal and accessory. The accessory gland may resemble the principal one but more often shows wide morphological divergence. The free-tailed bat, Tadarida thersites, is very unusual in that it has two sets of parotid glands rather than binary submandibular glands. We studied the ultrastructure of the principal parotid gland to establish a baseline for comparison with the accessory parotid. METHODS: Two specimens of adult free-tailed bats, one male and one female, were live-trapped in western Kenya. Parotid glands were fixed for electron microscopy using a protocol expressly designed for field fixation and then embedded by conventional means. RESULTS: Histologically, the principal parotid is a typical serous gland. The secretory granules of the endpiece cells have an unusual substructure in that they contain variable numbers of lucent halos and one or several spherules. Intercalated duct cells contain a significant number of dense, serous-like granules. Striated ducts have the usual basal configuration of mitochondria and folded plasma membranes, but the supranuclear cytoplasm contains many small, dense granules, so that these ducts resemble the granular convoluted tubules found in the submandibular glands of many families of rodents. The apices of the duct cells have a peculiar contour--the luminal surfaces obliquely invaginate into the apical cytoplasm, so that in thin section the luminal membranes appear to be underlaid by a layer of vacuoles. CONCLUSION: Although the principal parotid gland of the free-tailed bat shows some distinctive, species-specific ultrastructural features, it basically is similar to the parotid gland in two other molossid bats, Tadarida brasiliensis and Molossus molossus. The distinctive features in the principal parotid gland of T. thersites might relate to its feeding on hard-bodied insects and perhaps to the production of lysozyme.     

Proton NMR studies of cytochrome c peroxidase mutant N82A: hyperfine resonance assignments, identification of two interconverting enzyme ofecies, quantitating the rate of interconversion, and determination of equilibrium constants

The cyanide-ligated form of the baker's yeast cytochrome c peroxidase mutant bearing the mutation Asn82-->Ala82 ([N82A]CcPCN) has been studied by proton NMR spectroscopy. This mutation alters an amino acid that forms a hydrogen bond to His52, the distal histidine residue that interacts in the heme pocket with heme-bound ligands. His52 is a residue critical to cytochrome c peroxidase's normal function. Proton hyperfine resonance assignments have been made for the cyanide-ligated form of the mutant by comparison with 1-D and NOESY spectra of the wild-type native enzyme. For [N82A]CcPCN, proton NMR spectra reveal two significant phenomena. First, similar to results published for the related mutant [N82D]CcPCN [Satterlee, J. D., et al. (1994) Eur. J. Biochem. 244, 81-87], for Ala82 mutation disrupts the hydrogen bond between His52 and the heme-ligated CN. Second, four of the 24 resolved hyperfine-shifted resonances are doubled in the mutant enzyme's proton spectrum, leading to the concept that the heme active site environment is dynamically microheterogeneous on a very localized scale. Two magnetically inequivalent enzyme forms are detected in a pure enzyme preparation. Varying temperature causes the two enzyme forms to interconvert. Magnetization transfer experiments further document this interconversion between enzyme forms and have been used to determine that the rate of interconversion is 250 (+/- 53) s-1. The equilibrium constant at 20 degrees C is 1.5. Equilibrium constants have been calculated at various temperatures between 5 and 29 degrees C leading to the following values: delta H = 60 kJ mol-1; delta S = 0.20 kJ K-1 mol-1.     

Penetrating cardiac wounds: prospective study of factors influencing initial resuscitation

A prospective study of 66 consecutive patients with cardiac wounds seen over a 27-month period is reported. No patient was excluded. Patients were stratified by injury mechanism and by physiologic scoring at admission using the cardiovascular-respiratory elements of the Trauma Score (CVRS). Admission cardiac rhythm was obtained in patients with a CVRS of 0 and a Glasgow Coma Scale (GCS) score of 3. Information concerning the anatomic extent of the cardiac wound, the presence or absence of tamponade, and the degree of injury to other structures was also collected prospectively. Seventy percent of the cardiac wounds were caused by gunshots. The probability of successful resuscitation was significantly related to mechanism of injury and physiologic condition on arrival. Among patients arriving with a CVRS of 0 and a GCS score of 3, survival correlated with cardiac rhythm. Pericardial tamponade did not prove to be an independent predictor of early survival. The presence of tamponade was statistically linked to the mechanism of injury. Transport by non-official conveyance was associated with a higher CVRS on arrival. Intoxication with alcohol or cocaine had no evident effect on resuscitation probability.     

Neem oil as a sand fly (Diptera: Psychodidae) repellent

The repellent action of neem oil was evaluated against sand flies under laboratory and field conditions. Concentrations of 2% neem oil mixed in coconut or mustard oil provided 100% protection against Phlebotomus argentipes throughout the night under field conditions; against Phlebotomus papatasi it repelled sand flies for about 7 h in the laboratory. Neem oil is an indigenous product and a low-cost alternative for personal protection against sand fly bites.     

Reproductive preferences and fertility trends in post-transition Thailand

Two large national surveys in 1988 and 1933 provide new evidence on trends in family-size preferences in Thailand at a time when the Thai fertility transition is reaching its conclusion. Although the average preferred number of children has continued to decline, a resistant lower bound of two children is found for the vast majority of respondents, stemming, apparently, from a pervasive, although not inflexible, desire to have one child of each sex. Moreover, new evidence from birth-registration data indicates that the decline in the total fertility rate appears to have leveled off at about replacement level. These findings challenge the view that fertility in Thailand will continue to fall well below replacement level, and contradict recently expressed alarmist predictions of population decline in the foreseeable future.     

Check! a generic and specific industrial inspection tool

The authors present an overview of an `inspection and control' package to perform automatic quality control of industrial components, specifically electronic circuit boards. This application has grown out of a set of tools designed initially to aid the development of point distribution models (PDMs) and grey-level models (GLMs) pioneered at the Wolfson Image Analysis Unit in Manchester. These models are both generic and specific. Generic, because they can be applied to most image classification problems; specific, because they aim at the full interpretation of the variability of the objects to be modelled. The underlying vision processing techniques are based on statistical pattern matching. Two synergetic approaches have been followed. The system is trained to recognise the components from either their shape or their grey level appearance or both     

A prospective study of the efficacy of the physician order form for life-sustaining treatment

OBJECTIVES: The Physician Orders for Life-Sustaining Treatment (POLST), a comprehensive, one-page order form, was developed to convey preferences for life-sustaining treatments during transfer from one care site to another. This study examined the extent to which the POLST form ensured that nursing home residents' wishes were honored for Do Not Resuscitate (DNR) and requests for transfer only if comfort measures fail. DESIGN: The study used chart record data to follow prospectively a sample of nursing home residents with the POLST. SETTING: Eight geographically diverse, long-term, adult-care facilities in Oregon in which the POLST was in use. PARTICIPANTS: Nursing home residents (n = 180), who had a POLST recording DNR designation and who indicated a desire for transfer only if comfort measures failed, were followed for 1 year. MEASUREMENTS: For all subjects: treatment and disposition after significant health status changes; orders for narcotics and for provision or limitation of aggressive interventions. For hospitalized subjects: diagnosis, medical interventions, and DNR orders. For those who died: cause and location of death, life-sustaining treatments attempted, and comfort measures provided. RESULTS: No study subject received CPR, ICU care, or ventilator support, and only 2% were hospitalized to extend life. Of the 38 subjects who died during the study year, 63% had an order for narcotics, and only two (5%) died in an acute care hospital. A total of 24 subjects (13%) were hospitalized during the year. Hospitalized subjects' mean length of stay was 4.9 days, and the mean rate of hospitalizations for all subjects was 174 per 1000 resident years. In 85% of all hospitalizations, patients were transferred because the nursing home could not control suffering. In 15% of hospitalizations (n = 4), the transfer was to extend life, overriding POLST orders. CONCLUSIONS: POLST orders regarding CPR in nursing home residents in this study were universally respected. Study subjects received remarkably high levels of comfort care and low rates of transfer for aggressive life-extending treatments.     

Activity of renin-angiotensin-aldosterone system (RAAS) and vasopressin level in patients with primary pulmonary hypertension

AIM: Assessment of RAAS and vasopressin in patients with primary pulmonary hypertension (PPH). MATERIALS AND METHODS: Activity of plasma renin (APR), angiotensin-converting enzyme (ACE), plasma levels of angiotensin II (AII) and vasopressin (VP), serum concentration of aldosteron (AS) were measured by radioimmunoassay and enzyme immunoassay in 21 PPH patients with circulatory failure (age 34.7 +/- 2.1 years), 11 patients with NYHA functional class II-III, 10 with class IV, and 10 control subjects (age 29.8 +/- 1.5 years). RESULTS: Compared to controls, 21 PPH patients had elevated RAAS parameters: APR up to 3.52 ng/ml/h (p < 0.05), activity of ACE up to 43.13 units, AII level up to 33.93 ng/ml (p < 0.01), AS up to 468.86 ng/ml (p < 0.01), VP up to 5.26 ng/ml (p < 0.001). Circulatory failure progression resulted in activation of all the RAAS components. This and VP activation was the greatest in PPH patients with ACE > 5 ng/ml/h. PPH patients with mean pressure in the pulmonary artery higher than 60 mm Hg demonstrated higher ARP, AS, VP, AII, ACE than those who had this pressure under 60 mm Hg. CONCLUSION: PPH patients display a noticeable activation of RAAS and VP. This activation seems to be secondary as the changes increase with elevation of the pressure in the pulmonary artery and aggravation of circulatory insufficiency. Plasma renin activity determines the degree of RAAS activation as a whole. The discovered activation of RAAS in PPH gives grounds for doubts in the validity of using ACE inhibitors in the treatment of PPH.