Initiation into engineering : stability and change in gender orders

This article examines processes of doing gender during the initiation of students into engineering programs at university level in Sweden. The article draws on interviews with students, focusing on their understandings of gender. The aim is to explore difficulties with and challenges to traditional gender roles in an academic male dominated arena, by using theories of doing and undoing gender. The empirical material reveals the initiation period or ‘reception’ as a phenomenon both reinforcing and challenging traditional orders. The attempts to challenge norms meet resistance, revealing two paradoxes and one dilemma. In the first paradox the formal purpose of the reception (inclusion) is partly at odds with its informal consequence (exclusion of deviations). The second paradox concerns the contradictory effects of the reception. Even though the reception ensures participation of women, it reinforces existing hierarchies including gender inequality. This results in a dilemma, since in order to protect individual safety, there is a taboo on harassing women which then reproduces stable gender stereotypes. So while harassment taints the respect senior students must earn during the reception, the fact that female students exist in the engineering field challenges the established order and opens the way for change.

Investigation into the temporal stability of aqueous standard solutions of psilocin and psilocybin using high performance liquid chromatography

This paper reports an investigation into the temporal stability of aqueous solutions of psilocin and psilocybin reference drug standards over a period of fourteen days. This study was performed using high performance liquid chromatography utilising a (955% vlv) methanol: 10 mM ammonium formate,
pH 3.5 mobile phase and absorption detection at 269 nm. It was found that the exclusion of light significantly prolonged the useful life of standards, with aqueous solutions of both psilocin and psilocybin being stable over a period of seven days.

The determination of the local conditions for void initiation in front of a crack tip for materials with second-phase particles

A procedure is proposed to determine, for second-phase particles near a crack tip, the maximum particle stresses at the moment of void initiation by either particle fracture or particle/matrix interface separation. A digital image analysis system is applied to perform a quantitative analysis of corresponding fracture surface regions from stereo image pairs taken in the scanning electron microscope. The fracture surface analysis is used to measure, for individual particles, the crack tip opening displacement at the moment of void initiation and the particle location with respect to the crack tip. From these data, the stress tensor at the moment of void initiation is calculated from the Hutchinson–Rice–Rosengren (HRR) field theory. The corresponding average local stresses within the particle are evaluated by a non-linear Mori–Tanaka-type approach. These stresses are compared to estimates according to the models by Argon et al. [A.S. Argon, J. Im, R. Safoglu, Metall. Trans. 6 (1975) 825] and Beremin [F.M. Beremin, Metall. Trans. 12 (1981) 723]. The procedure is demonstrated on an Al6061–10% Al2O3 metal matrix composite.

Phase formation and physical properties of mechanically alloyed amorphous 55Mg35Ni1OSi

Amorphous 55Mg35Ni10Si alloy powder has been synthesized by mechanical alloying technique using pure Mg, Ni and Si elemental powders. The transformation of the crystalline powders into an amorphous one has been investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and differential scanning calorimetry. The new material produced has a higher thermal stability than reported results, which is beneficial to the fabrication of Mg–Ni–Si bulk amorphous components through powder metallurgy.

Examination of the "all hazards" approach to disaster management as applied to field disaster management and pre-hospital care in Australia

Disasters, emergencies, incidents, and major incidents - they all come back to the same thing regardless of what they are called. The common denominator is that there is loss of life, injury to people and animals and damage and destruction of property. The management of such events relies on four phases: 1. Prevention 2. Preparation 3. Response 4. Recovery Each of these phases is managed in a different way and often by different teams. Here, concentration has been given to phases 2 and 3, with particular emphasis on phase 3, Response. The words used to describe such events are often related to legislation. The terminology is detailed later. However, whatever the description, whenever prevention is not possible, or fails, then the need is to respond. Response is always better when the responders are prepared. Training is a major part of response preparation and this book is designed to assist those in the health industry who need to be ready when something happens. One of the training packages for responders is the Major Incident Medical Management and Support (MIMMS) Course and this work was designed to supplement the manual prepared by Hodgetts and Macway-Jones(87) in the UK. Included is what the health services responder, who may be sent to an event in which the main concern is trauma, should know. Concentration is on the initial response and does not deal in any detail with hospital reaction, the public health aspects, or the mental health support that provides psychological help to victims and responders, and which are also essential parts of disaster management. People, in times of disaster, have always been quick to offer assistance. It is now well recognised however, that the 'enthusiastic amateur', whilst being a well meaning volunteer, isn't always what is needed. All too often such people have made things worse and have sometimes ended up as victims themselves. There is a place now for volunteers and there probably always will be. The big difference is that these people must be well informed, well trained and well practiced if they are to be effective. Fortunately such people and organisations do exist. Without the work of the St John Ambulance, the State Emergency Service, the Rural Fire Service the Red Cross and the Volunteer Rescue Association, to mention only a few, our response to disasters would be far less effective. There is a strong history of individuals being available to help the community in times of crisis. Mostly these people were volunteers but there has also always been the need for a core of professional support. In the recent past, professional support mechanisms have been developed from lessons learned, particularly to situations that need a rapid and well organised response. As lessons are learned from an analysis of events, philosophy and methods have changed. Our present system is not perfect and perhaps never will be. The need for an 'all-hazards approach' makes detailed planning very difficult and so there will probably always be criticisms about the way an event was handled. Hindsight is a wonderful thing, provided we learn from it. That means that this text is certainly not the 'last word' and revisions as we learn from experience will be inevitable. Because the author works primarily in New South Wales, many of the explanations and examples are specific to that state. In Australia disaster response is a State, rather than a Commonwealth, responsibility and consequently, and inevitably, there are differences in management between the states and territories within Australia. With the influence of Emergency Management Australia, these differences are being reduced. This means that across state and territory boundaries, assistance is common and interstate teams can be deployed and assimilated into the response rapidly, safely, effectively and with minimum explanation. This text sets out to increase the understanding of what is required, what is in place and how the processes of response are managed. By way of introduction and background, examples are given of those situations that have occurred, or could happen. Man Made Disasters has been divided into two distinct sections. Those which are related to structures or transport and those related directly to people. The first section, Chapter 3, includes: • Transport accidents involving land, rail, sea or air vehicles. • Collapse of buildings for reasons other than earthquakes or storms. • Industrial accidents, including the release of hazardous substances and nuclear events. A second section dealing with the consequences of the direct actions of people is separated as Chapter 4, entitled 'People Disasters'. Included are: • Crowd incidents involving sports and entertainment venues. • Terrorism From Chapter 4 on, the emphasis is on the Response phase and deals with organisation and response techniques in detail. Finally there is a section on terminology and abbreviations. An appendix details a typical disaster pack content. War, the greatest of all man made disasters is not considered in this text.

Austenite stability in Fe-Mn-Si-based shape memory alloys

The stability of austenite in a number of Fe–Mn–Si-based shape memory alloys has been investigated. It was found that a grain boundary precipitate of BCC structure is formed over a wide range of alloy compositions and heat treatment temperatures. This grain boundary phase has been identified as the chi (χ) phase. Although up to 3 vol.% of the grain boundary precipitate was generated by isothermal aging in the range 500–800 °C, it was found not to markedly affect the mechanical properties or the shape memory effect. Nano-indentation indicated that the hardness and strength of the parent and precipitate phase are very similar, as are their compositions.

Solid state ion transport and phase behaviour in composites of N,N-methyl propylpyrrolidinium tetrafluoroborate and amorphous polyethylene oxide

The binary and ternary addition of 2 wt.% LiBF₄ and 2 wt.% amorphous polyethylene oxide (aPEO) respectively to the plastic crystal forming salt P₁₃BF₄ (where P₁₃⁺=methylpropyl pyrrolidinium cation) was investigated with specific focus on the phase behaviour and evaluation of transport characteristics. Differential scanning calorimetry (DSC), optical thermomicroscopy, solid state nuclear magnetic resonance (NMR), and AC impedance spectroscopy were used to develop an understanding of the conduction process in the pure and mixed systems. The morphology of the ternary compound appeared as hexagonal spherulites upon solidification. Multinuclear NMR Pulsed Field Gradient measurements (¹H,¹⁹F,⁷Li) to probe both cation and anion diffusion coefficients are reported. The anion is shown to be the most diffusive (at 320 K:¹⁹F=2.5×10⁻¹¹ m² s⁻¹; 1H: 1.8×10⁻¹¹ m² s⁻¹; ⁷Li: 1.1×10⁻¹¹ m² s⁻¹) in the ternary compound, with enhanced conductivity (2.7×10⁻⁵ S cm⁻¹ at 310 K) just below the melt.

Thermal stability of the Al70Ni10Ti10Zr5Ta5 amorphous alloy powder fabricated by mechanical alloying

An Al₇₀Ni₁₀Ti₁₀Zr₅Ta₅ amorphous alloy powder was fabricated by mechanical alloying. The phase structure and characteristic temperatures of the alloy were determined by X-ray diffraction, transmission electron microscopy and differential scanning calorimetry. The glass transition behavior and crystallization kinetics were analyzed using Lasocka and Kissinger functions. The results show that the alloy has a higher crystallization temperature, a higher effective activation energy of crystallization and a wider supercooled liquid region than the previously reported values, suggesting a high thermal stability and promising applications.

Proton transport in choline dihydrogen phosphate/H3PO4 mixtures

Mixtures of the plastic crystal material choline dihydrogen phosphate [Choline][DHP] and phosphoric acid, from 4.5 mol% to 18 mol% H₃PO₄, were investigated and shown to have significantly higher proton conductivity compared to the pure [Choline][DHP]. This was particularly evident from the electrochemical hydrogen reduction reaction and the proton NMR diffusion measurements, in addition to ionic conductivity measured from the impedance spectroscopy. The ionic conductivity was observed to increase by more than an order of magnitude in phase I (i.e. the highest temperature solid phase in [Choline][DHP]) reaching up to 10⁻² S cm⁻¹. The multinuclear NMR spectroscopy data suggest that, at least on the timescale of the NMR measurement, the H⁺ cations and [DHP] anions are equivalent in both phases. The pulsed field gradient NMR diffusion measurements of the 18 mol% acid sample indicate that all three ions are mobile, however the H⁺ diffusion coefficient is an order of magnitude higher than for the [Choline] cation or the [DHP] anion, and therefore conduction in these materials is dominated by proton conductivity. The thermal stability, as measured by TGA, is unaffected with increasing acid additions and remains high; i.e. no significant mass loss below 200 °C.

Evaluating the stability of disulfide bridges in proteins: a torsional potential energy surface for diethyl disulfide

Disulfide bonds formed by the oxidation of cysteine residues in proteins are the major form of intra- and inter-molecular covalent linkages in the polypeptide chain. To better understand the conformational energetics of this linkage, we have used the MP2(full)/6-31G(d) method to generate a full potential energy surface (PES) for the torsion of the model compound diethyl disulfide (DEDS) around its three critical dihedral angles (χ2, χ3, χ2′). The use of ten degree increments for each of the parameters resulted in a continuous, fine-grained surface. This allowed us to accurately predict the relative stabilities of disulfide bonds in high resolution structures from the Protein Data Bank. The MP2(full) surface showed significant qualitative differences from the PES calculated using the Amber force field. In particular, a different ordering was seen for the relative energies of the local minima. Thus, Amber energies are not reliable for comparison of the relative stabilities of disulfide bonds. Surprisingly, the surface did not show a minimum associated with χ2 − 60°, χ390, χ2′ − 60°. This is due to steric interference between Hα atoms. Despite this, significant populations of disulfides were found to adopt this conformation. In most cases this conformation is associated with an unusual secondary structure motif, the cross-strand disulfide. The relative instability of cross-strand disulfides is of great interest, as they have the potential to act as functional switches in redox processes.

Optical phase change at the interface between mica and thin silver film

We describe a simple experiment which allows unequivocal determination of optical phase change upon reflection of light at the mica-silver interface. While the physical origin of such a phase change at the dielectric-metal interface is well understood to lie in absorption of electromagnetic energy by the metal, inconsistency and ambiguity has persisted as to what its sign and magnitude should be in the field of thin film optics. Most commonly, it has been assigned to be negative for mathematical convenience or just arbitrarily. Our finding shows that with the convention exp(-iωt) for time dependence of the electromagnetic wave, the phase change at the interface between mica and the thin silver film is necessarily positive and its magnitude falls between π and 3π/2 for silver thicknesses down to nanometres. This gives a physically reasonable correspondence to an increased equivalent thickness of the dielectric material, and it clarifies the assignment of interference orders in the harmonic series in a spectrum.

Psychological needs of adolescents in the early phase of bipolar disorder : implications for early intervention

Aim: This paper will describe the rationale for, and importance of, psychological interventions for young people early in the course of bipolar disorder.
Methods: Emerging literature in this field will be discussed in addition to describing specific clinical challenges and opportunities with this population.
Results: In order to be more developmentally appropriate for young people with bipolar disorder, eight aspects of clinical work which may require modification were identified.
Conclusions: The evidence base for the effectiveness of psychological interventions for people diagnosed with bipolar disorder is growing. However, some aspects relating to working with adults with bipolar disorder require modification to be effective in working with young people early in the course of the disorder.

Electrochemiluminescent monomers for solid support syntheses of Ru(II)-PNA bioconjugates : multimodal biosensing tools with enhanced duplex stability

The feasibility of devising a solid support mediated approach to multimodal Ru(II)-peptide nucleic acid (PNA) oligomers is explored. Three Ru(II)-PNA-like monomers, [Ru(bpy)2(Cpp-L-PNA-OH)]2+ (M1), [Ru(phen)2(Cpp-L-PNA-OH)]2+ (M2), and [Ru(dppz)2(Cpp-L-PNA-OH)]2+ (M3) (bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, dppz = dipyrido[3,2-a:2′,3′-c]phenazine, Cpp-L-PNA-OH = [2-(N-9-fluorenylmethoxycarbonyl)aminoethyl]-N-[6-(2-(pyridin-2yl)pyrimidine-4-carboxamido)hexanoyl]-glycine), have been synthesized as building blocks for Ru(II)-PNA oligomers and characterized by IR and 1H NMR spectroscopy, mass spectrometry, electrochemistry and elemental analysis. As a proof of principle, M1 was incorporated on the solid phase within the PNA sequences H-g-c-a-a-t-a-a-a-a-Lys-NH2 (PNA1) and H-P-K-K-K-R-K-V-g-c-a-a-t-a-a-a-a-lys-NH2 (PNA4) to give PNA2 (H-g-c-a-a-t-a-a-a-a-M1-lys-NH2) and PNA3 (H-P-K-K-K-R-K-V-g-c-a-a-t-a-a-a-a-M1-lys-NH2), respectively. The two Ru(II)-PNA oligomers, PNA2 and PNA3, displayed a metal to ligand charge transfer (MLCT) transition band centered around 445 nm and an emission maximum at about 680 nm following 450 nm excitation in aqueous solutions (10 mM PBS, pH 7.4). The absorption and emission response of the duplexes formed with the cDNA strand (DNA: 5′-T-T-T-T-T-T-T-A-T-T-G-C-T-T-T-3′) showed no major variations, suggesting that the electronic properties of the Ru(II) complexes are largely unaffected by hybridization. The thermal stability of the PNA·DNA duplexes, as evaluated from UV melting experiments, is enhanced compared to the corresponding nonmetalated duplexes. The melting temperature (Tm) was almost 8 °C higher for PNA2·DNA duplex, and 4 °C for PNA3·DNA duplex, with the stabilization attributed to the electrostatic interaction between the cationic residues (Ru(II) unit and positively charged lysine/arginine) and the polyanionic DNA backbone. In presence of tripropylamine (TPA) as co-reactant, PNA2, PNA3, PNA2·DNA and PNA3·DNA displayed strong electrochemiluminescence (ECL) signals even at submicromolar concentrations. Importantly, the combination of spectrochemical, thermal and ECL properties possessed by the Ru(II)-PNA sequences offer an elegant approach for the design of highly sensitive multimodal biosensing tools.