Search Results - (Author, Cooperation:D. Pearson)

2018-03-06

Oxford University Press

0035-8711

1365-2966

Physics

2015-02-24

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Alanine/*analogs & derivatives/chemistry ; Archaeal Proteins/*chemistry ; Biphenyl Compounds/*chemistry ; Computer Simulation ; Computer-Aided Design ; Crystallography, X-Ray ; Entropy ; Models, Chemical ; Protein Structure, Secondary ; Pyrococcus abyssi/*enzymology ; Software ; Threonine-tRNA Ligase/*chemistry

2013-02-08

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Carbon Cycle/*physiology ; Carbon Dioxide/analysis/*metabolism ; Cell Respiration ; *Climate Change ; *Models, Theoretical ; Photosynthesis ; Rain ; Temperature ; Trees/*metabolism ; *Tropical Climate ; Uncertainty

0021-9673

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

1089-7623

AIP Digital Archive

Physics

Electrical Engineering, Measurement and Control Technology

The University of Wisconsin-Madison Accredited Dosimetry Calibration Laboratory has designed and constructed an Attix style variable-length free-air ionization chamber for application in mammographic energy x-ray beams. The chamber is designed to enable absolute in-air exposure measurements. A unique feature of this design is that the variation in plate separation is accomplished by use of two stepping motor controlled translation stages. This paper details the characterization of this instrument and presents some preliminary exposure measurement results. © 1995 American Institute of Physics.

Electronic Resource

1365-2214

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Psychology

Parents’ perceptions of how they were told that their child has special needs were examined. Thirty-nine families on the Isle of Wight completed a structured interview. Participants formed two groups. The first group comprised of 23 families who had a child aged from birth to 5 years with special needs. In the second group there were 16 families who had a child aged between 15 and 20 years with special needs. Parents were asked about their perceptions of how their child's special needs were disclosed, their satisfaction with how they were told and what improvements they would have liked. Differences between the two cohorts were examined, and changes in how services were perceived were investigated. Overall, parents in the group with younger children were more satisfied about the way in which they were told that their child had special needs than those with older children. Implications for service delivery and future research are considered.Keywords: special needs, disclosure

Electronic Resource

1089-7550

AIP Digital Archive

Physics

We report on controlled changes in the coercivity of sputter deposited Pt/Co multilayer films by thermal treatment under controlled atmospheres. The as-sputtered coercivities of typically 3.3 kOe can be increased to 10.5 kOe by annealing in air, however for coercivities greater than 6 kOe the rectangular ratio of the multilayer decreases with increasing coercivity. The loop shape can be regained and the coercivity decreased by annealing in a H2/N2 atmosphere.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

Nanochannel glass (NCG)-based lithography has been used in conjunction with electron cyclotron resonance microwave plasma reactive ion etching (ECR-RIE) to demonstrate deep submicron features in HgCdTe alloys and InAs/GaSb heterostructures. NCG-based lithography is attractive as a massively parallel, low cost technology for nanometer-scale patterning. Samples patterned using thin-film metal replicas of NCG and methyl-radical-based ECR-RIE demonstrate a high degree of uniformity and fidelity with individual features having nearly vertical sidewalls and aspect ratios of up to 2 to 1. Dot arrays with features as small as 250 nm (and with packing densities of ∼1010/cm2) and anti-dot arrays with features as small as 600 nm have been realized.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

We report a linear correlation between the total intensities of the L2,3 white lines in electron energy loss spectra and the number of unoccupied 3d states in 3d transition metals. We show that this correlation can be used to obtain quantitative information about electronic changes during alloying and during solid-state phase transformations.

Electronic Resource

1089-7550

AIP Digital Archive

Physics

The stress dependence of the intrinsic change in Young's modulus with magnetic field (the ΔE effect, DE) has been measured to 120 MPa in Terfenol-D (Tb0.27Dy0.73Fe2−x, 0〈x〈0.1) with the field H as a parameter. The sample, prepared by rf rapid zoning,1 consists of slablike dendrites with the [112¯] growth direction determining the longitudinal (stress and field) axis of the sample. A [111] direction is normal to the longitudinal axis. The data (Fig. 1) show an extremely large (eightfold) depression in Young's modulus, comparable to that found in Fe-based amorphous materials. Earlier measurements on polycrystalline samples yielded DE=1.6. The value of DE observed here is attributed to the "jumping'' of the magnetization between two easy axes of magnetization. These directions are stress dependent, parallel to the magnetically easy 〈111〉 directions at low stress. One rotates to a direction 14.75° from the [111] direction at high stress. A calculation of the stiff (high-field) Young's modulus in the [112¯] direction using "infinite field'' single-crystal elastic constants yielded a value of 114 GPa. The lower value in Fig. 1 is consistent with this result since Δc44∼1/H. Calculation of the field dependence of the modulus caused by "jumping'' of the moment will be presented.

Electronic Resource

1089-7623

AIP Digital Archive

Physics

Electrical Engineering, Measurement and Control Technology

Ultrasoft x rays are a useful probe for mechanistic studies of radiation damage in living cells. The highly localized energy deposition from a low energy x-ray occurs in a volume comparable to the sensitive biological targets within a cell, so that these low-energy x rays can be used as a tool to investigate radiation effects on the subcellular level. In the ultrasoft x-ray energy region the bright intensity and tunable energy selection of synchrotron radiation is unmatched by conventional sources. A beamline and irradiation chamber for dosimetry and radiation biology studies has been set up at the ES-0 exposure station of the Center for X-ray Lithography at Aladdin. The beamline includes a 10-μm-thick Be entrance window and a combination filter and single synthetically fabricated multilayer mirror for energy selection. The irradiation chamber contains another Mylar window for isolation, a two-dimensional scanning system allowing a 400-cm2 exposure area with scanning rates up to 3.5 cm/s, a rotating feedthrough system that enables motion in the third dimension, several viewports and a specially designed cell sample holder which can be filled with gases at various pressures and holds up to 18 cell culture dishes. The system has been characterized with a gas flow proportional counter to determine energy bandpass and spectral purity and a calorimeter and ionization chamber to assess photon intensity at various energies within the range 500–2000 eV.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

We have, for the first time, demonstrated integrated dc superconducting quantum interference devices (SQUIDs) with input coils of linewidth down to 0.5 μm. The SQUID inductance L consists of a single octagonal washer or two or four such washers configured in parallel. The input coil of inductance Li, which couples to L with a mutual inductance of Mi, consists of fine-line octagonal spiral(s) fabricated in close proximity to the washer(s). For a two-washer SQUID with twin 80-turn, 0.5 μm spirals, Li=2.5 μH, Mi=12.7 nH, L=109 pH, and the coupling constant k2=0.85. This entire device occupies an area of less than 0.2 mm2.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

We have demonstrated a new planarized all-refractory technology for low Tc superconductivity (PARTS). With the exception of the Nb-AlOx-Nb trilayer preparation, the processing is done almost exclusively within an advanced Si technology fabrication facility. This approach has allowed us to leverage highly off of existing state-of-the-art lithography, metal etching, materials deposition, and planarization capabilities. Using chemical-mechanical polish as the planarization technique we have fabricated Josephson junctions ranging in size from 0.5–100 μm2. Junction quality is excellent with the figure of merit Vm typically exceeding 70 mV. PARTS has yielded fully functional integrated Josephson devices including magnetometers, gradiometers, and soliton oscillators.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

A theory of ballistic electron emission microscopy is presented that incorporates constant tunnel current feedback and models the band structure and space charge effects on the electron transmission. The computation is beyond the effective mass approximation but short of being from first principles. We compare theory and experimental Au/GaAs(001) dI/dV data and find that the L point does not contribute to an observable threshold and that the corresponding experimental feature is due to band structure effects. © 2000 American Institute of Physics.

Electronic Resource

1600-0838

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Sports Science

The purpose of this investigation was to examine calf muscle strength and cross-sectional area in 29 middle-aged men (current mean=48.4±3.1 years) who had significant differences in their physical activity levels. These men were initially evaluated to determine the physiological requirements for successful distance running in the late 1960s at a time when they were all considered elite distance runners. Based on their training regimens in the interim between testing, subjects were described as highly trained (HI; n=10), fitness trained (FIT; n=12), or untrained (UT; n=7). In addition, an aged-matched sedentary group (CON; n=7) was tested. Each subject was evaluated for Vo2max plantar flexion calf muscle strength and cross-sectional area (CSA) of the lower leg (gastrocnemius and soleus). Muscle CSA was determined by computed tomography, whereas calf strength measurements were made using a specially designed leg restraint system and an isokinetic dynamometer. There were no significant differences in plantar flexion strength (at 60 and 180°/s) or CSA of the gastrocnemius and soleus muscles among the groups. Calf muscle strength per CSA was also similar at both test velocities for all groups. These data demonstrate that middle-aged distance runners who have continued to run at a relatively high level for 20–25 years have similar calf muscle CSA and strength compared with aged-matched males who run significantly less or not at all.

Electronic Resource

1471-0528

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1365-2621

Blackwell Publishing Journal Backfiles 1879-2005

Process Engineering, Biotechnology, Nutrition Technology

Summary. Methods for determining various chemical spoilage values in meat, previously considered in some detail by the author, have been applied to various samples of beef to which sulphur dioxide and chlortetracycline had been added.The incorporation into minced beef of these preservatives when compared with the effect on untreated meat, caused retardation of proteolytic breakdown as measured by the relative increases of the total volatile nitrogen during storage. There was also a corresponding delay in the fall of the extract-release volumes. Concurrently fat hydrolysis increased at a considerably faster rate than the controls.

Electronic Resource

1365-2621

Blackwell Publishing Journal Backfiles 1879-2005

Process Engineering, Biotechnology, Nutrition Technology

One of the main purposes of quality control is the economical production of standardized products which show the minimum variation from one day to the next. In formulating products various factors have to be considered such as relevant legal and specification requirements, organoleptic acceptability and changes which take place during processing and storage. Raw materials, intermediates and the product are controlled between pre-arranged limits by employing physical and chemical tests at appropriate stages.Foods such as flour and margarine have to be artificially fortified. the Food Standards Committee have accepted the necessity of adding approved compounds to some foods to improve colour and texture or to inhibit putrefaction. Although raw materials are checked for purity, contaminants may be picked up during the process unless constant vigilance is practised.

Electronic Resource

1365-2044

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Changes in the electroencephalograms of patients undergoing cardiac surgery with cardiopulmonary bypass were studied. An analysis technique with a simple display of amplitude and frequency within the traditional bands was used. During the course qf an operation, there can be dramatic changes in frequency contribution with little or no change in overall EEG amplitude. Evaluation of the results shows that this technique clearly draws attention to periods of EEG change, and examples are given.

Electronic Resource

1365-2044

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource