Search

The anomalously low thermal expansion of Fe–Ni Invar has long been associated with magnetism, but to date, the microscopic underpinnings of the Invar behaviour have eluded both theory and experiment. Here we present nuclear resonant X-ray scattering measurements of the phonon and magnetic entropies under pressure. By applying a thermodynamic Maxwell relation to these data, we obtain the separate phonon and magnetic contributions to thermal expansion. We find that the Invar behaviour stems from a competition between phonons and spins. In particular, the phonon contribution to thermal expansion cancels the magnetic contribution over the 0–3 GPa pressure range of Invar behaviour. At pressures above 3 GPa, the cancellation is lost, but our analysis reproduces the positive thermal expansion measured separately by synchrotron X-ray diffractometry. Ab initio calculations informed by experimental data show that spin–phonon interactions improve the accuracy of this cancellation over the range of Invar behaviour. Spin–phonon interactions also explain how different phonon modes have different energy shifts with pressure.

Selection of women for treatment-focused genetic testing (TFGT) following a new diagnosis of breast cancer is changing. Increasingly a patient’s age and tumour characteristics rather than only their family history are driving access to TFGT, but little is known about the impact of receiving carrier-positive results in individuals with no family history of cancer. This study assesses the role of knowledge of a family history of cancer on psychosocial adjustment to TFGT in both women with and without mutation carrier-positive results. In-depth semistructured interviews were conducted with 20 women who had undergone TFGT, and who had been purposively sampled to represent women both family history and carrier status, and subjected to a rigorous qualitative analysis. It was found that mutation carriers without a family history reported difficulties in making surgical decisions quickly, while in carriers with a family history, a decision regarding surgery, electing for bilateral mastectomy (BM), had often already been made before receipt of their result. Long-term adjustment to a mutation-positive result was hindered by a sense of isolation not only by those without a family history but also those with a family history who lacked an affected relative with whom they could identify. Women with a family history who had no mutation identified and who had not elected BM reported a lack of closure following TFGT. These findings indicate support deficits hindering adjustment to positive TFGT results for women with and without a family history, particularly in regard to immediate decision-making about risk-reducing surgery.

There's nothing out of the ordinary about an archaeologist excavating a sacred Maya temple structure in the heart of Central America. There are hundreds of archaeologists carrying out fieldwork all [...]

Radio-guided occult lesion localisation using iodine-125 seeds (ROLLIS) is a novel method of localisation for impalpable in situand invasive carcinomas that has been the subject of a recent pilot study and pilot study extension in Western Australia. Robust protocols for radiation safety, specimen labelling, specimen tracking, seed retrieval and seed disposal were developed at two Western Australian laboratories to minimise the risk of seed loss. The processes are safe and effective with no significant radiation exposure to pathologists and with acquisition of all seeds intact and undamaged. The success can be attributed to developing specific seed retrieval techniques, suited to local preferences at each institution, with input from surgeons, radiologists and medical physics personnel. These techniques are now routine and will continue in the randomised control phase of the ROLLIS study.

Using Hyper Suprime Camera data (a precursor of what is to come with Rubin Observatory) we assess trail masking mitigation strategies for satellite contamination. We examine HSC data of the Hubble COSMOS field where satellite trails have been identified by eye. Exercising the current LSST Science Pipelines on this data, we study the efficacy of masking satellite trails which appear in single visit exposures before they are assembled into a coadded frame. We find that the current routines largely mask satellite trails in single visits, but miss the extended low surface brightness features of the satellite trails. For a sufficiently wide mask, these faint features appear at a less significant level in the final coadd, as they are averaged down in a stack of tens of exposures. We study this print-through vs mask width. In this note, we describe some of the challenges we encountered in that effort, prospects for more complete removal of the low surface brightness tails of the masked trails, and possible science impacts.

AbstractOpen fronted ventilated enclosures are commonly used in industry to control worker exposure to a wide range of chemicals. These enclosures tend to be of basic design and often consist of nothing more than a box like structure with an open front to allow worker access and extraction at the rear to remove contaminated air. This design forces the worker to stand at the face of the enclosure and by doing so presents a blockage to the airflow.The aim of this experimental study was to investigate design parameters that influence the control effectiveness of small ventilated partial enclosures. All experimental work was carried out in a purpose built, free standing, partial enclosure with and without a manikin present. Sulphur hexafluoride (SF6) was used as the test gas and released via two different designed ejectors inside the enclosure. Air samples were taken in the breathing zone of the manikin and the SF6concentration measured. Two different rear baffles and four flanges, which were fitted to the opening of the enclosure, were tested at face velocities between 0.3 and 0.7 ms-1.The presence of a manikin at the face of the enclosure caused a ‘wake’ region of highly turbulent air to form in front of it. This ‘wake’ interacted with the eddy against the floor of the enclosure. Of the four flanges tested only one, which allowed air to pass between the wall of the enclosure and the flange, significantly reduced the concentration of SF6in the breathing zone of the manikin. This flange was considered to be the most practical design for small partial enclosures.

Purpose: Imaging the pregnant or lactating breast can prove a challenge with malignancy either obscured or masquerading as a benign mass. Pregnancy related, or gestational breast cancer occurs in 24 of every 100,000 pregnancies. It is vital to exclude malignancy in women at any age, whether pregnant or not, who present with breast symptoms and imaging is an important part of this work up. Methods: This paper reviews the current world knowledge of how best to image the breast in women who are pregnant or lactating. It includes the authors' own case series of 22 women identified from the Western Australian Gestational Breast Cancer Project and cases diagnosed at Royal Perth Hospital up to the end of March 2007 for whom breast imaging studies were available for review. Results/discussion: We discuss the imaging characteristics of gestational breast cancer as described in the world literature. Results demonstrate that most, but not all, pregnant and lactating breasts have high density but there is up to 100% negative predictive value for mammography and ultrasound. Despite the increased density mammography and/or ultrasound reveal positive findings when cancer is present in up to 90% of cases. Image guided biopsy is important to confirm a diagnosis. Conclusion: Imaging the breasts during pregnancy or lactation adds valuable information in the work up of a breast symptom. We provide an algorithm for the investigation of pregnant and/or lactating women with a palpable breast mass.

AbstractIf inhaled, welding fumes can be harmful to health, thus exposure must be controlled. A commonly used method of control is local exhaust ventilation (LEV) in the form of moveable capturing hoods but, to achieve efficient capture, this type of ventilation must be positioned close to the fume source and moved as welding progresses, although in practice re-location may not always occur. Alternatively, control may be exercised using a low volume high velocity system (LVHV), fitted either to an existing welding torch or manufactured as an integral part of a torch. This type of system is commonly referred to as ‘on-gun’ extraction. Its primary benefit is that the extraction is always positioned close to the fume source and that it extracts less air than traditional moveable capture hoods. However, welders complain that the high velocity of the extracted air can remove the shielding gas and, hence, compromise weld metal integrity.Following tests to evaluate the effect of extract nozzle position, the capture efficiency of an integrated on-gun system was measured during bead on plate and horizontal/vertical fillet welding both in the flat and in position. Weld metal integrity was assessed by examining the welds produced during testing for porosity. Other factors such as ergonomics and operability were not assessed.The work showed that the integral on-gun fume extraction system evaluated provided efficient fume capture, without compromising weld metal integrity, and that the system was easy to optimise. However, some ambiguities remained regarding the capture efficiencies achievable during fillet welding in the flat and further work is required before the use of on-gun extraction can be recommended for this particular welding configuration.

The primary mechanism for clearance of extracellular dopamine (DA) is uptake mediated by the dopamine transporter (DAT), which is governed, in part, by the number of functional DATs on the cell surface. Previous studies have shown that amphetamine (AMPH) decreases DAT cell surface expression, whereas insulin reverses this effect through the action of phosphatidylinositol 3-kinase (PI3K). Therefore, it is possible that AMPH causes DAT cell surface redistribution by inhibiting basal insulin signaling. Here, we show in a heterologous expression system and in murine striatal synaptosomes that AMPH causes a time-dependent decrease in the activity of Akt, a protein kinase immediately downstream of PI3K. This effect was blocked by the DAT inhibitor cocaine, suggesting that AMPH must interact with DAT to inhibit Akt. We also showed that AMPH is able to stimulate Ca2+/calmodulin-dependent kinase II (CaMKII) activity, both in the heterologous expression system as well as in murine striatal synaptosomes. The ability of AMPH to decrease Akt activity was blocked by the CaMKII inhibitor 2-[N-(2-hydroxyethyl)]-N-(4-methoxybenzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine (KN93), but not by its inactive analog 2-[N-(4-methoxybenzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine (KN92). Furthermore, preincubation with KN93 prevented the AMPH-induced decrease in DAT cell surface expression. Thus, AMPH, but not cocaine, decreases Akt activity through a CaMKII-dependent pathway, thereby providing a novel mechanism by which AMPH regulates insulin signaling and DAT trafficking.

A revolution is challenging the dogma that local treatment for all patients with breast cancer treated with breast conservation therapy must include postoperative radiotherapy delivered to the whole breast. Such prolonged postoperative radiotherapy is a burden to patients and hospitals and forces many women to chose mastectomy instead. Furthermore, for patients receiving chemotherapy, the start of conventional radiotherapy may be delayed so long as to increase the risk of local relapse. These problems might be eliminated if effective radiotherapy could be given as a single treatment intraoperatively, immediately after the surgery. Local recurrence after breast-conserving surgery usually occurs in the portion of the breast in the immediate proximity of the tumor, even when radiotherapy is omitted. Therefore, it should usually be possible to restrict radiotherapy to only the area adjacent to the tumor in selected women. Based on this premise, we have devised a new technique of partial breast irradiation, with the intention of completing all local treatment in a single session. In this article, we elaborate on the rationale and on the different methods of delivering intraoperative radiotherapy. If this approach is validated in ongoing randomized trials, it could save time, money, and breasts.

The success of zoos and aquariums as conservation centres depends on the holistic embrace of conservation, including acting as model citizen, wildlife conservationist, agent for conservation and mentor/trainer. Success also depends on truly reaching our audiences, from policy‐maker to land manager to citizen, to help them care about and care for nature. In pursuing our conservation goal, we must acknowledge our general lack of experience in effectively changing the behaviour of these different audiences, which function at both the global and local level. To start with those closest to us, the visitors to our institutions, we should appreciate that we do not have deep understanding of the effect our business has on them by providing close‐up experiences with a variety of animals. Nevertheless, by the caring ways in which we express biophilia and carry out particular conservation activities, our institutions can become transformative models, inspiring and motivating urban people around the globe to have a more harmonious and sustainable relationship with the natural world.

The damage to steel moment frames observed in the Northridge earthquake of 1994 led to requirements in codes for use of tested connections, when these systems were to be employed in new buildings. One of the primary goals of the FEMA/SAC project was to develop guidelines for the design of steel moment frames that would return the design process to a relatively simple set of procedures similar to those used in the design of other lateral force-resisting systems. Recommended Seismic Design Criteria for New Steel Moment-Frame Buildings, FEMA-350, presents design guidelines for use of steel moment frames in new buildings, developed from the FEMA/SAC research. This paper provides a general summary of the criteria, and a description of the prequalified connections and recommendations for their use.

Abstract: Lathrolestes nigricollis(Thomson) and Grypocentrus albipes Ruthe,Palearctic specialist parasitoids of thebirch-leafmining sawfly Fenusa pusilla(Lepeletier), were imported from central Europe andreleased at three locations in Edmonton, Alberta,Canada during 1994–1996. Parasitoids becameestablished at two locations, L. nigricollis atboth and G. albipes at one, and were recoveredfor 3–5 years after release. Lathrolestesnigricollis has dispersed throughout most ofEdmonton, and at least 13 km from release sites, butG. albipes has been recovered only 400–500 mfrom one release site. Five years after introductionat one site, percent parasitism by L.nigricollis was 78% and 84% for the first andsecond generations, respectively, and about 48% ofparasitoid eggs were encapsulated.

Positron emission tomography (PET) is being increasingly used as an accurate and non-invasive modality in diagnosis, staging and post-therapy assessment in patients with lung cancer. In this study, we examine whether the uptake of [(18)F]fluorodeoxyglucose (FDG), a marker of increased glucose metabolism in neoplastic cells, is of prognostic value in patients with primary lung cancer.

An aeroacoustic investigation was performed to assess the effects of adding mass flow at the trailing edges of stators upstream of an aircraft engine simulator. By using trailing edge blowing to minimize the shed wakes of the stators, the flow into the rotor was made more uniform, hence reducing the unsteady stator–rotor interaction. In these experiments, a reduced number of stators (four) was used in a 1/14 scale model inlet which was coupled to a 4·1in (10·4 cm) turbofan engine simulator. Steady state measurements of the aerodynamic flow field and acoustic far field were made in order to evaluate the aeroacoustic performance at three simulator speeds: 30k, 50k, and 70kr.p.m. The lowest test speed (30k r.p.m.) showed a noise reduction as large as 8·9dB in the blade passing tone. At 50k and 70kr.p.m., the reduction in blade passing tone was 5·5 and 2·6dB respectively. In addition, trailing edge blowing reduced the overall sound pressure level in every case. Aerodynamic measurements showed that fan face distortion was significantly reduced due to trailing edge blowing. The addition of trailing edge blowing from the four upstream stators did not change the operating point of the fan, and the mass flow added by the blowing was less than 1% of the fan mass flow rate. The results of these experiments clearly demonstrate that blowing from the trailing edges of the stators is effective in reducing unsteady stator–rotor interaction and the subsequent forward radiated noise.

One of the important surprises of the Northridge earthquake of January 17, 1994, was the widespread and unanticipated brittle fracture of welded steel beam-to-column connections. Although no casualties or collapses occurred during the Northridge earthquake as a result of these connection failures, and many WSMF buildings were not damaged at all, a wide spectrum of brittle connection damage did occur, ranging from minor cracking to completely severed columns. This paper summarizes two of the most important documents that have been developed in response to the damage suffered to steel moment frame buildings in the Northridge earthquake. The first, FEMA 267, Interim Guidelines: Evaluation, Repair, Modification and Design of Welded Steel Moment Frame Structures, was generated from studies undertaken as part of a project initiated by the U.S. Federal Emergency Management Agency (FEMA) to reduce the earthquake hazards posed by steel moment-resisting frame buildings. The second document addressed in this paper is the 1997 edition of the American Institute of Steel Construction (AISC) Seismic Provisions for Structural Steel Buildings(commonly referred to as the AISC Seismic Provisions) that incorporates the new information generated by the FEMA-sponsored project and other investigations on the seismic performance of steel structures, and has been adopted by reference into the 2000 International Building Code (IBC).

ObjectivesThe purpose of this study was to demonstrate how child death review teams can be used to prevent future deaths through retrospective, multiagency case analysis and recommendations for educational programs and policy change.MethodsA listing of all deaths to persons ages 21 years and younger in Philadelphia that occurred in 1995 was compiled by the Philadelphia Interdisciplinary Youth Fatality Review Team (PIYFRT), a multiagency, multidisciplinary, community based group created in 1993 with the mission to prevent future deaths through review, analysis, and initiation of corrective actions. Data were collected on demographic variables, as well as the circumstantial variables on injuries such as weapon type, alcohol and drug use, and contact with the criminal justice system, among others. Each case was reviewed thoroughly to determine whether or not the death was preventable. Selected injury related death cases were analyzed further by demographic and circumstantial variables.ResultsIn 1995, 607 children ages 21 years and younger died in Philadelphia from natural causes (61.6%), unintentional injuries (16.3%), homicide (18.6%), suicide (2.3%), and undetermined causes (1.2%). More than a third (37.2%) of all deaths were considered preventable. Of the injury deaths (n=224), 95% were judged to be preventable. Preventable fire/burn injury deaths (n=29) were associated with lack of a smoke detector, non-supervision of children, and faulty home appliances. Violent deaths were associated with substance abuse, gang involvement, chronic truancy, academic failure, and access to weapons.ConclusionsRelevant policies for these preventable or intervenable deaths are discussed such as use of non-battery powered smoke detectors.

The concentration of heavy metals (Cd, Cu, Pb, Ni and Zn) and organochlorine contaminants (PCBs, DDT, DDE and DDD) in the blubber of 12 adult male Cape fur seals, Arctocephalus pusillus pusillus, inadvertently caught in trawl nets off the Eastern Cape coast of South Africa during commercial fishing operations between May 1993 and October 1994, was investigated. The median and range of concentrations for each metal were, in μg/g wet weight: Cd, 0.4 (<0.04-0.53); Cu, 2.6 (2.17-7.43); Pb, 0.7 (0.54-0.99); Ni, 17.7 (9.39-23.18) and Zn, 11.5 (3.14-16.65). Dry weights were: Cd, 0.5 (<0.04-0.59); Cu, 2.9 (2.47-8.45); Pb, 0.6 (0.54-1.14); Ni, 17.0 (10.79-28.22) and Zn, 12.8 (3.61-20.26). Concentrations of Cd, Pb and Zn were in the limits of reported values; however Cu and Ni levels were considerably higher. There is no evidence that the elevated levels of Cu and Ni reported in this study would pose a serious threat to the health of individual animals; however, high concentrations of these metals may be sufficient to result in some additional stress to animals when they mobilise their lipid reserves during illness or starvation. Ni and Cd concentrations appeared to increase with age; however, small sample size prevented statistical analysis. Concentrations of organochlorines (μg/g wet weight) were below the limit of detection.

A generalized method of surface definition and replication for cylindrical type objects of compound curvature is presented. The interactive approach is suited to mini-computer installations used in conjunction with standard three-axis NC machines. The compound curvature surface is defined by a new form of central perspective shadow moire contourography called pericontourography. The resulting digital data are treated in such a way that a quasi-helical cutter path is generated which may be applied directly to an NC milling machine (mill turning) or an NC lathe. Specifying the surface in terms of the subsequent machining process avoids the use of complex surface fitting and reformating routines. Interference with the spherical ended tool and the object surface is automatically tested and corrections to the cutter path are made.

Several methodologies of surface modifications were applied to polycrystalline alumina (PCA) samples to study their effects on surface morphology and frictional coefficients. Modified surfaces were first tested in a specially designed frictional apparatus against wires of stainless steel (SS) and beta-titanium (ß-Ti) alloys and then evaluated by scanning electron microscopy. Techniques included ion implantation of chromium ions (Cr+), ion beam assisted deposition of diamond-like carbon (DLC), coatings of gamma-irradiated polymers (PEO), and electroless nickel plating of a composite material of polytetrafluoroethylene dispersed in a nickel phosphorus matrix, Niflor NT® (NF). Implanting ions into the bulk material had no effect on surface morphology. Although covering the surface, the DLC coating mimicked the underlying topography. The coatings of PEO and NF obliterated and smoothed over the normally rough and faceted PCA surfaces. When compared to control samples, neither the Cr+ or DLC process reduced the friction normally seen against SS and ß-Ti wires. When tested in both the dry and wet states, the PEO coated samples retained their traditional levels of frictional resistance. Only the composite material, NF, successfully reduced the friction when compared with controls. Although this composite coating is not recommended for oral use, the results show that simply smoothing over the rough surface is inadequate for friction reduction; the surface must somehow also be made lubricious.

Tout le monde s'accorde maintenant a reconnaitre que le mouvement de l'air dans les maisons est un facteur important a la fois pour les risques de condensation et pour la bonne utilisation de l'energie, mais les methodes d'essai conventionnelles ont des limites. Grace a un analyseur gazeux a caneaux multiples et un ordinateur, le Scottish Laboratory du BRE a developpe les techniques d'essais et de mesures conventionnelles de facon a obtenir une estimation plus realiste des processus impliques, comme l'explique ici M.Saunders. Des etudes in situ ont permis de verifier l'importance du bouchage des interstices dans le plafond, car 20 a 30% de l'air entrant dans une maison en sortira, via le comble, par ces interstices qui sont dangereux pour le transfert d'humidite mais moins importants pour la transmission de la chaleur.

Recent avenues of research have improved our understanding of the chemistry of nitrocellulose. With this in mind, a brief review of the chemistry of nitrocellulose is presented. While not comprehensive in nature, this review does point out some of the underlying characteristics of nitrocellulose which are of interest to the propellant community.

Ice crystal clouds have an influence on the radiative budget of the earth; however, the exact size and nature of this influence has yet to be determined. A laboratory cloud chamber experiment has been set up to provide data on the optical scattering behaviour of ice crystals at a visible wavelength in order to gain information which can be used in climate models concerning the radiative characteristics of cirrus clouds. A PMS grey-scale probe is used to monitor simultaneously the cloud microphysical properties in order to correlate these closely with the observed radiative properties. Preliminary results show that ice crystals scatter considerably more at 90° than do water droplets, and that the halo effects are visible in a laboratorygenerated cloud when the ice crystal concentration is sufficiently small to prevent masking from multiple scattering.

On-line Gel Permeation Chromatography/Fourier Transform Infrared (GPC/FT-IR) spectroscopy has been used to develop a method for the determination of the nitrogen content of cellulose nitrates. The method is based upon the solution infrared spectrum of the cellulose derivative in tetrahydrofuran. Making use of the second derivative of the spectra, wherein antisymmetric ONO stretches for both primary and secondary carbon nitration are discernible, has eliminated the relative concentration dependence of the absorption. This feature has permitted the determination of the nitrogen content of cellulose nitrates throughout their molecular weight distribution.

Juvenile dermatomyositis in fourteen children who had not responded fully to steroids and other immunosuppressants and who had had chronic active disease for an average of 3 years was successfully treated with cyclosporin. Twelve patients had serious complications of the disease or of previous treatment. The response to cyclosporin included recovery of muscle strength and function and resolution of complications. It was possible to stop steroids or to reduce the steroid dose, which had previously been difficult, in all fourteen patients. In general, a low dose of cyclosporin (2·5-7·5 mg/kg daily) was sufficient and no serious side-effects were seen.

AbstractRecent developments in the area of thunderstorm electrification processes are reviewed. These processes have two main divisions; (a) convective, in which particles charged by ion capture are moved by convection currents to strengthen the electric field in the cloud, and (b) processes involving charge transfer during particle interactions, following which oppositely charged particles move apart in the updraft to form the observed charge centers. Type-b processes are further subdivided into inductive (relying on the preexistence of an electric field) and noninductive charge-transfer mechanisms. Field and laboratory evidence points to the importance of interactions between particles of the ice phase, in the presence of liquid water droplets, in separating electric charge in thunderstorms. Recent experimental studies have investigated the dependence of charge transfer on the size and relative velocity of the interacting particles and have determined the dependence of the sign of the charge transfer on temperature and cloud liquid water content. Field data upon which the laboratory simulations are based are obtained by increasingly sophisticated airborne and ground-based means. Calculations of electric field growth using experimental charge-transfer data in numerical models of the dynamical and microphysical development of thunderstorms show agreement with observations, although further refinement is required. Some directions for future research are outlined.

The effect of elevated temperatures on conventional packed bonded-phase columns used in supercritical-fluid chromatography (SFC) has been investigated. The impact of column conditioning temperature on the capacity factor, peak width, and peak asymmetry on octadecyl and propylamino columns from five commerical suppliers is reported.

Aztreonam was compared with aminoglycoside antibiotics (tobramycin and amikacin) in a randomized, prospective, clinical trial in serious infections caused by gram-negative bacilli (GNB). A total of 43 evaluable patients with 47 infected sites were treated with aztreonam, and 41 evaluable patients were treated with aminoglycosides for 43 infections. Of patients treated with aztreonam, 17 were bacteremic, as were 12 of those treated with aminoglycosides. Clinical and microbiologic response rates were similar, except that only 5 of 11 patients with pneumonia were considered to be clinically cured with aminoglycoside therapy, while 5 of 6 patients with pneumonia treated with aztreonam were cured. Renal impairment was observed in 9 of 54 patients who received aminoglycoside antibiotics, but in only 2 of 53 patients treated with aztreonam. Hearing impairment developed in one patient treated with tobramycin. Transient elevations of serum transaminase levels occurred in 9 of 53 patients treated with aztreonam and in only 2 of 54 aminoglycoside-treated patients. Diarrhea and superinfection occurred with equal frequency in both groups. Serum concentrations of bactericidal activity could not be correlated with the outcome of therapy. Aztreonam appears to have comparable clinical efficacy with aminoglycoside antibiotics for the treatment of serious infections caused by aerobic and facultative GNB. Its use as a single agent for the treatment of serious lower respiratory infections caused by GNB warrants further evaluation.

This paper reports on a field study that addresses three important dimensions of information use in decision making: (1) how combinations of information source and medium change over time as executive decision-making processes unfold; (2) how the rate of information acquisition affects media selection; and (3) how media usage patterns feed into and out of meetings. The findings extend the integrated literature of information acquisition and decision making, introduce the notion that the velocity of information acquisition influences media selection during the decision-making process, and expand the understanding of executive information gathering in the practice of business. The authors identify potential applications for information systems practice and raise critical issues to help focus future research.

A computer-aided sculpting system for use in prosthetics is described. The prosthetist's sculpting tools now consist of a computer, a graphics terminal, a mouse and an on-screen moveable cursor. Accompanied by the system software, these tools allow systematic modification of a primitive socket using techniques analogous to those used by a prosthetist working with rasps and plaster.

This study has identified the infrared asymmetric nitrate absorptions of cellulose nitrates observed in THF solution. Independent absorptions for the primary nitrate at C6and secondary nitrate at C3were observed at 1651 cm−1and 1639 cm−1, respectively. In addition, a third absorption at 1667 cm−1was observed to be dependent upon the degree of nitration of the cellulose nitrate. This absorption was found to be due to steric hindrance between secondary nitrate groups on the C2and C3sites.

Stationary-phase cells of Saccharomyces cerevisiae were found to have a reduced polyadenylate [poly(A)] content as compared with exponential-phase cells. A sizing procedure for poly(A) was devised to distinguish between alternative hypotheses to explain this reduction. Two major size classes of poly(A) were found. The decreased representation of the larger of the two classes accounted for the majority of the poly(A) loss. The remainder of the loss was accounted for by fewer poly(A)-containing sequences. The smaller of the two poly(A) classes was apparently not of mitochondrial origin and may be added transcriptionally.

An unusually large chondrosarcoma arising in the hand of a young patient with multiple hereditary exostoses is presented.

The alpha 2A adrenergic receptor (alpha 2AAR) previously was shown to be directly delivered to and retained on the lateral subdomain of renal epithelial cells. The present studies demonstrate that, in contrast, wild-type and epitope-tagged canine A1 adenosine receptors (A1AdoR) are apically enriched (65-83%) in Madin-Darby canine kidney (MDCKII) and porcine renal epithelial (LLC-PKI) cells, based on surface biotinylation strategies detecting photoaffinity-labeled A1AdoR. Confocal microscopy corroborated the apical enrichment of the epitopetagged A1AdoR. Metabolic labeling studies revealed that this steady-state polarization is achieved by direct delivery to both the apical (60-75%) and basolateral surface. Growth of A1AdoR-expressing cells as monolayers presence of A1AdoR antagonists, which decreased cell growth, suggesting that A1AdoR elicit MDCKII cell proliferation. The preferential apical but detectable basolateral localization of A1AdoR provides a molecular understanding of published reports that functional responses can be elicited following apical as well as basolateral delivery of adenosine agonists in varying renal preparations. These findings also suggest that receptor chimeras derived from the Gi/Go-protein-coupled alpha 2AAR and A1AdoR will be informative in revealing structural features critical for basolateral versus apical targeting.

A 4.0-kilobase DNA fragment containing the developmentally regulated gene for glucose dehydrogenase (gdh) from Bacillus subtilis was incorporated into the plasmid pGX345, which contains a marker conferring chloramphenicol resistance (cat). The resistance marker of the resulting integration vector was used to map the gdh gene on the B. subtilis chromosome. Using PBS1 transduction, the gene order was determined to be aroI cat (gdh) mtlB dal. The cat (gdh) marker was also cotransformable with mtlB. The genetic location of the gdh gene established by this indirect method was confirmed by the fact that the original phage lambda EF2, containing a 10-kilobase B. subtilis DNA fragment from which the 4-kilobase gdh region had been subcloned, also contained the mtlB gene.

Using human adipose stromal cells in monolayer culture as a model system for study of the regulation of aromatase activity, as well as polyclonal antibodies raised in this laboratory against aromatase cytochrome P-450 (cytochrome P-450AROM), it was found that the rate of synthesis of cytochrome P-450AROM was stimulated by dibutyryl cyclic AMP. This stimulation was attenuated by epidermal growth factor and was potentiated by phorbol esters. These changes in cytochrome P-450AROM synthesis were associated with comparable changes in the levels of translatable cytochrome P-450AROM mRNA, as well as with changes in the activity of aromatase of these cells. By contrast, there was little change in the synthesis of the reductase component of the aromatase enzyme complex in response to these factors. The increase in mRNA was blocked by cycloheximide, indicative of a requirement for protein synthesis in mediating this inductive response. It is concluded that aromatase activity is regulated primarily by changes in the level of mRNA encoding cytochrome P-450AROM, and that such changes are likely a reflection of changes in the rate of transcription of the gene encoding this enzyme. Increases in the levels of cytochrome P-450AROM mRNA are apparently mediated by a regulatory protein(s), similar to that found for other steroidogenic forms of cytochrome P-450.

A Reference Library of socket shapes for an Above-Knee Computer Aided Socket Design (CASD) System has been created. This library forms part of a more general CASD System (Dean & Saunders, 1985; Novicov & Foort, 1982). It consists of a matrix of reference shapes representing above-knee socket characteristics and is based upon skeletal structure, residuum length and tissue mass. A set of 27 biomechanical reference shapes in the form of male plaster casts were produced by a combination of CNC milling and traditional artisan techniques. Each reference shape was digitized to obtain its cylindrical coordinates. Cross-sectional areas and tissue distributions within each shape and between the shapes were analyzed, modified and then stored numerically within the computer for further implementation of the CASD System for the above-knee amputees. The creation and the analysis of the reference shape data is described.