Partition coefficients of environmentally important phenols in a supercritical carbon dioxide-water system from cocurrent extraction without analysis of the compressible phase

Partition coefficients of phenol, salicylic acid, and several environmentally important chloro- and nitrophenols in a supercritical CO2-water system were measured using direct cocurrent extraction of aqueous solutions of the individual solutes with CO2. Partitioning data on the nitrophenols and salicylic acid were obtained for the first time. To bypass the troublesome and error-prone analysis of the CO2-rich phase, the present method employed only the solute concentrations in the aqueous phase before and after extraction to determine the partition coefficient. Unlike most previous engineering studies of phenol partitioning in a CO2-water system, the concentrations of phenolic solutes approached infinite dilution in both phases. This makes the results relevant to analytical-scale SFE of environmental water samples with CO2. Because of effective infinite dilution of the solutes, the partition coefficients provide a direct measure of relative CO2-philicity/hydrophilicity of the individual phenols. Compared to the octanol-water partition coefficients of substituted phenols, the CO2-water partition coefficients are more sensitive to substitution in the position neighboring the hydroxyl group.     

Oestrogen's masculine side: mediation of mating in male mice

This review focuses on the role of oestrogen in male sexual behaviour using oestrogen receptor alpha and beta knockout (ERalphaKO and ERbetaKO) mouse models. ERbetaKO mice are capable of mating and producing offspring, whereas ERalphaKO mice are unable to do either. When ERalphaKO males are treated with testosterone or dihydrotestosterone (DHT), < 50% display mounting behaviour, few intromit and none ejaculate. However, concurrent treatment with testosterone and a dopamine agonist instates masculine sexual behaviour in both male and female ERalphaKO mice. Dopamine content in the preoptic area and associated regions is not affected by oestrogen receptor alpha gene disruption. However, expression of neuronal nitric oxide synthase immunoreactivity is severely reduced in ERalphaKO males compared with wild-type males. These findings, together with studies conducted in aromatase knockout mice, are at odds with the dogma that oestrogen is required during development for expression of male sexual behaviour in adults. However, they do support a role for oestrogens, mediated by oestrogen receptor alpha, in regulation and production of neuronal nitric oxide synthase, which in turn may control dopamine agonist release. As has been shown in male rats, in mice dopamine agonist release is likely to be an essential component of the neural pathway that mediates male sexual behaviour.     

Modeling the behavior of the 4/5ths rule for determining adverse impact: Reasons for caution.

The Equal Employment Opportunity Commission's 4/5ths rule has been used for over 20 years in applied psychology and employment law. The rule signals that there is adverse impact when the protected group selection ratio is less than 80% of the highest scoring group's selection ratio. We conducted several simulations and found, consistent with some previous management science literature, that the 4/5ths rule often resulted in false-positive readings of adverse impact even when there were no underlying (population) standardized group differences between subgroups. We then incorporated tests of statistical significance and found that adding such tests to the 4/5ths rule eliminated many false-positive indications of adverse impact. We also examined simulated selection systems based on meta-analytic values from the selection literature. The frequency of adverse impact signals from the 4/5ths rule increased markedly relative to simulations with no subgroup population differences. Adding statistical tests mitigated the number of indications of adverse impact to some extent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deuterium retention in sintered boron carbide exposed to a deuterium plasma

Depth profiles of deuterium up to a depth of 10 μm have been measured using the D(³He,p)⁴He nuclear reaction in a resonance-like technique after exposure of sintered boron carbide, B₄C, at elevated temperatures to a low energy (≈200 eV/D) and high ion flux (≈10²¹ m⁻² s⁻¹) D plasma. The proton yield was measured as a function of incident ³He energy and the D depth profile was obtained by deconvolution of the measured proton yields using the program SIMNRA. D atoms diffuse into the bulk at temperatures above 553 K, and accumulate up to a maximum concentration of about 0.2 at.%. At high fluences (?10²⁴ D/m²), the accumulation in the bulk plays a major role in the D retention. With increasing exposure temperature, the amount of D retained in B₄C increases and exceeds a value of 2 × 10²¹ D/m² at 923 K. The deuterium diffusivity in the sintered boron carbide is estimated to be D = 2.6 × 10⁻⁶exp{−(107 ± 10) kJ mol⁻¹/RT} m² s⁻¹.     

Fabrication and characterization of two-color midwavelength/long wavelength HgCdTe infrared detectors

High-performance 20-μm unit-cell two-color detectors using an n-p⁺-n HgCdTe triple-layer heterojunction (TLHJ) device architecture grown by molecular beam epitaxy (MBE) on (211)-oriented CdZnTe substrates with midwavelength (MW) infrared and long wavelength (LW) infrared spectral bands have been demonstrated. Detectors with nominal MW and LW cut-off wavelengths of 5.5 μm and 10.5 μm, respectively, exhibit 78 K LW performance with >70 % quantum efficiency, reverse bias dark currents below 300 pA, and RA products (zero field of view, 150-mV bias) in excess of 1×10³ Ωcm². Temperature-dependent current-voltage (I–V) detector measurements show diffusion-limited LW dark current performance extending to temperatures below 70 K with good operating bias stability (150 mV ± 50 mV). These results reflect the successful implementation of MBE-grown TLHJ detector designs and the introduction of advanced photolithography techniques with inductively coupled plasma (ICP) etching to achieve high aspect ratio mesa delineation of individual detector elements with benefits to detector performance. These detector improvements complement the development of high operability large format 640×480 and 1280×720 two-color HgCdTe infrared focal plane arrays (FPAs) to support third generation forward looking infrared (FLIR) systems.     

The yeast Ty virus-like particles

Virus-like particle (VLP) assembly is a crucial step of the life cycle of retrotransposons. The S. cerevisiae Ty elements represent an interesting model for the analysis of these particles and thus have been studied extensively. Our current knowledge of the organisation and assembly of Ty1 and Ty3 VLPs is reviewed here. This includes the mechanism of assembly, the role of the Tya core protein during VLP formation and the RNA packaging process. The physical properties of Ty1 VLPs are also described and the latest three-dimensional Ty1 VLP reconstructions are shown. In addition, the relevance of these studies is discussed in the context of retro-element biology.     

An S1 gradient of refractoriness is not essential for reentry induction by an S2 stimulus

This communication reports a numerical simulation of reentry induction by successive stimulation (S1-S2) that does not require an S1 gradient of refractoriness. The S1 action potential is uniform in space, so before the S2 stimulus there is no refractory gradient. Nevertheless, a unipolar S2 stimulus initiates quatrefoil reentry. The result supports the growing realization that virtual electrodes, hyperpolarization, de-excitation, and break excitation may be important during reentry induction.     

‘DreamTeam’: A platform for synchronous collaborative applications

This paper presents a platform for developing, testing and executing synchronous collaborative applications in a distributed, heterogeneous environment. Even though several environments exist nowadays, specific problems are not treated satisfactorily. Especially in real network environments, problems like unstable network connections and low bandwidths have to be considered.The DreamTeam platform addresses the special needs of environments with non-optimal characteristics which can, be found in distance learning scenarios. DreamTeam comprises a development environment, a simulation environment and a runtime environment; it is based upon the concept of a fully decentralised architecture and encourages rapid prototyping.DreamTeam supports developers of shared applications through a component concept. Using components helps to divide a software project into well-defined parts. Well-documented interfaces help to reduce integration efforts and improve software quality. A selection of sample applications with DreamTeam validates our design concept.This paper is an extended version of Roth, J. and Unger, C. (1998). DreamTeam: A Platform for Synchronous Collaborative Applications. In Herrmann, Th. and Just-Hahn, K. (eds)Groupware und organisatorische Innovation (D-CSCW '98). B.G. Teubner, Stuttgart, 153–165.     

The appropriateness of use of percutaneous transluminal coronary angioplasty in New York State

Between 1974 and 1989 we prospectively observed 530 patients with brucellosis. The findings for 62 patients (42 males and 20 females; mean age, 34.7 years) with 63 episodes in which the sacroiliac joint was involved (the most frequent osteoarticular location [11.7%]) were analyzed. Ten of the older patients (mean age, 55.3 years) had concomitant spondylitis. Systemic symptoms were usually important, and characteristic pain and findings of sacroiliitis were observed in approximately 75% of cases. Blood cultures were positive for Brucella melitensis for 44 patients. The most frequent radiographic findings were blurring of articular margins (42 cases) and widening of the sacroiliac space (20 cases). No radiographic anomalies were detected in 13 cases. Results of 99mTc and gallium-67 bone scans were abnormal in approximately 90% of cases (abnormalities were often mild). Overall, clinical, radiographic, and isotopic bone scan findings were sensitive and useful, although they were occasionally minimal or difficult to evaluate, making diagnostic findings confusing or misleading. Brucellar sacroiliitis is a mild disease associated with a good outcome similar to that observed for patients with uncomplicated brucellosis.     

A group therapist's (analyst's) lament.

Comments on the article by D. Daskovsky (see record 1997-38798-001) on issues in resistance and countertransference in the treatment of adults who were sexually abused as children. The article adds weight to the perception among uninformed psychologists and psychoanalysts that analytic group psychotherapy (analytically informed) is the unrecognized offspring of psychoanalysis in the US. (PsycINFO Database Record (c) 2010 APA, all rights reserved)