bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cognitive and neurobiological alterations in electromagnetic hypersensitive patients: results of a case-control study
Authors: Landgrebe M. , Frick U. , Hauser S. , Langguth B. , Rosner R. , Hajak G. , Eichhammer P. 
Published: March 2008

BackgroundHypersensitivity to electromagnetic fields (EMF) is frequently claimed to be linked to a variety of non-specific somatic and neuropsychological complaints. Whereas provocation studies often failed to demonstrate a causal relationship between EMF exposure and symptom formation, recent studies point to a complex interplay of neurophysiological and cognitive alterations contributing to symptom manifestation in electromagnetic hypersensitive patients (EHS). However, these studies have examined only small sample sizes or have focused on selected aspects. Therefore this study examined in the largest sample of EHS EMF-specific cognitive correlates, discrimination ability and neurobiological parameters in order to get further insight into the pathophysiology of electromagnetic hypersensitivity.MethodIn a case-control design 89 EHS and 107 age- and gender-matched controls were included in the study. Health status and EMF-specific cognitions were evaluated using standardized questionnaires. Perception thresholds following single transcranial magnetic stimulation (TMS) pulses to the dorsolateral prefrontal cortex were determined using a standardized blinded measurement protocol. Cortical excitability parameters were measured by TMS.ResultsDiscrimination ability was significantly reduced in EHS (only 40% of the EHS but 60% of the controls felt no sensation under sham stimulation during the complete series), whereas the perception thresholds for real magnetic pulses were comparable in both groups (median 21% versus 24% of maximum pulse intensity). Intra-cortical facilitation was decreased in younger and increased in older EHS. In addition, typical EMF-related cognitions (aspects of rumination, symptom intolerance, vulnerability and stabilizing self-esteem) specifically differentiated EHS from their controls.ConclusionsThese results demonstrate significant cognitive and neurobiological alterations pointing to a higher genuine individual vulnerability of electromagnetic hypersensitive patients.
Prevalence and sociodemographic correlates of depression in an elderly population living with family members in Beijing, China
Authors: Ma X. , Xiang Y.-T. , Li S.-R. , Xiang Y.-Q. , Guo H.-L. , Hou Y.-Z. , Cai Z.-J. , Li Z.-B. , Li Z.-J. , Tao Y.-F. , Dang W.-M. , Wu X.-M. , Deng J. , Ungvari G. S. , Chiu H. F. K. 
Published: March 2008

BackgroundTo date, there has been no large-scale survey of geriatric depression (GD) involving both rural and urban areas in China using standardized assessment tools and diagnostic criteria. This study aimed to determine the 12-month and lifetime prevalence rates of GD and sociodemographic correlates in urban and rural regions of Beijing, China.MethodA total of 1601 elderly patients (aged ⩾60 years) were randomly selected and interviewed in Beijing using the Composite International Diagnostic Interview (CIDI 1.0). Basic sociodemographic and clinical data were also collected during the interviews.ResultsThe overall 12-month prevalence of GD was 4.33%, and the 12-month prevalence rates for men and women were 2.65% and 5.83% respectively. The overall lifetime prevalence of GD was 7.83%, and lifetime prevalence rates for men and women were 4.65% and 10.66% respectively. Female sex, lower educational level, monthly income, rural abode, and the presence of one or more major medical conditions were associated with increased risk of GD. Of the GD subjects interviewed, 25.2% were receiving some type of treatment, with only 4.7% preferring to seek treatment from mental health professionals.ConclusionsAlthough still relatively low by international standards, there is an increasing trend in the prevalence of GD in China. The low percentage of subjects treated for GD is a major public health concern that should be addressed urgently.
Ethnicity, socio-economic status and self-harm in Swedish youth: a national cohort study
Authors: Jablonska B. , Lindberg L. , Lindblad F. , Hjern A. 
Published: March 2008

BackgroundPrevious studies have shown an elevated risk for self-harm in adolescents from ethnic minorities. However, potential contributions to this risk from socio-economic factors have rarely been addressed. The main aim of this article was to investigate any such effects.MethodA national cohort of 1009 157 children born during 1973–1982 was followed prospectively from 1991 to 2002 in Swedish national registers. Multivariate Cox analyses of proportional hazards were used to estimate the relative risk of hospital admission for self-harm. Parental country/region of birth was used as proxy for ethnicity.ResultsYouth with two parents born outside Sweden (except those from Southern Europe) had higher age- and gender-adjusted hazard ratios (HRs) of self-harm than the majority population (HR 1.6–2.3). The HRs decreased for all immigrant groups when socio-economic factors were accounted for but remained significantly higher for immigrants from Finland and Western countries and for youth with one Swedish-born and one foreign-born parent.ConclusionsSocio-economic factors explain much of the variation by parental country of birth of hospital admissions for self-harm in youth in Sweden.
High bone turnover but normal bone mineral density in women suffering from schizophrenia
Authors: Bergemann N. , Parzer P. , Mundt C. , Auler B. 
Published: March 2008

BackgroundA potential association between schizophrenia and osteoporosis or osteopenia has recently been reported. Various factors affect bone mineral density (BMD) such as polydipsia, nicotine, alcohol abuse, lack of physical activity, an unbalanced diet, a lack of ultraviolet exposure and/or vitamin D. In addition, decreased BMD in women with schizophrenia has been attributed to drug-induced hyperprolactinaemia and/or secondary hypogonadism. This study was undertaken because empirical evidence from larger patient cohorts is limited and the data are still controversial.MethodSeventy-two premenopausal, regularly menstruating women suffering from schizophrenia and 71 age- and sex-matched healthy controls were included in the study. Biochemical markers of bone turnover (serum osteocalcin, urinary pyridinium crosslinks), parathyroid hormone and 25-hydroxyvitamin D were measured. BMD at the femoral neck and lumbar spine was determined by dual-energy X-ray absorptiometry in a subgroup of 59 patients. In addition, 17β-oestradiol, prolactin, testosterone, gonadotrophins and dehydroepiandrosterone sulfate were measured.ResultsCompared with healthy controls, both markers of formation and resorption were increased in women with schizophrenia. However, in the subgroup of 59 patients, BMD was within the normal range. In women suffering from schizophrenia, testosterone levels were higher than in controls, and serum oestradiol levels were lower compared with the normal range.ConclusionDespite significantly increased bone turnover, we conclude that premenopausal and regularly menstruating women suffering from schizophrenia have normal spine and hip BMD. This may be due to the opposite effects of the various parameters influencing bone metabolism, especially of the gonadal hormones, and due to an intact coupling mechanism.
Lexical Representations in Children With SLI: Evidence From a Frequency-Manipulated Gating Task
Authors: Mainela-Arnold Elina , Evans Julia L. , Coady Jeffry A. 
Published: March 2008

Purpose
This study investigated lexical representations of children with specific language impairment (SLI) and typically developing, chronological age-matched (CA) peers on a frequency-manipulated gating task. The study tested the hypothesis that children with SLI have holistic phonological representations of words, that is, that children with SLI would exhibit smaller effects of neighborhood density on gating durations than CA peers and that children with SLI would be as efficient as CA peers in accessing high-frequency words but that they would differ from their age-matched peers in accessing low-frequency words.

Method
Thirty-two children (ages 8;5–12;3 [years;months]) participated: 16 children with SLI and 16 typically developing peers matched on age and nonverbal IQ. Children’s word guesses after different gating durations were investigated.

Results
Contrary to predictions, no group differences in effects of distributional regularity were found: Children in both groups required equally longer acoustic chunks to access words that were low in frequency and came from dense neighborhoods. However, children with SLI appeared to vacillate between multiple word candidates at significantly later gates when compared with children in the CA group.

Conclusions
Children with SLI did not exhibit evidence for phonologically holistic lexical representations. Instead, they appeared more vulnerable to competing words.
The Acceptance of Background Noise in Adult Cochlear Implant Users
Authors: Plyler Patrick N. , Bahng Junghwa , von Hapsburg Deborah 
Published: March 2008

Purpose
The purpose of this study was to determine (a) if acceptable noise levels (ANLs) are different in cochlear implant (CI) users than in listeners with normal hearing, (b) if ANLs are related to sentence reception thresholds in noise in CI users, and (c) if ANLs and subjective outcome measures are related in CI users.

Method
ANLs and the Hearing in Noise Test (HINT; M. Nilsson, S. Soli, & J. Sullivan, 1994) were examined in 9 adult CI users and 15 adult listeners with normal hearing. In addition, the Abbreviated Profile of Hearing Aid Benefit (APHAB; R. M. Cox & G. C. Alexander, 1995) and a satisfaction questionnaire were administered to CI users only.

Results
Results indicated that (a) ANLs were not significantly different for CI users and listeners with normal hearing, (b) ANLs were not correlated with HINT values for either group, (c) ANL was not significantly correlated with APHAB scores, and (d) ANL was significantly correlated with overall CI benefit on the satisfaction questionnaire.

Conclusions
CI users with large ANLs reported more benefit from implants than those with small ANLs. The results of this preliminary study of ANL in CI users suggest that ANL can be used as a tool for evaluating processing in noise in individual CI users.
Binaural Advantage for Younger and Older Adults With Normal Hearing
Authors: Dubno Judy R. , Ahlstrom Jayne B. , Horwitz Amy R. 
Published: March 2008

Purpose
Three experiments measured benefit of spatial separation, benefit of binaural listening, and masking-level differences (MLDs) to assess age-related differences in binaural advantage.

Method

Participants were younger and older adults with normal hearing through 4.0 kHz. Experiment 1 compared spatial benefit with and without head shadow. Sentences were at 0
o
, and speech-shaped noise was at 0
o
, 90
o
, or ±90
o
. Experiment 2 measured binaural benefit with the near ear unplugged compared with plugged for sentences at 0
o
and masker at 90
o
. Experiment 3 measured MLDs under earphones for 0.5-kHz pure tones in Gaussian and low-noise noise, and spondees in speech-shaped noise.

Results
Spatial-separation benefit for speech did not differ significantly for younger and older adults but was smaller than predicted by an audibility-based model for older adults and larger than predicted for younger adults. Binaural listening benefit was observed for younger participants only. Tonal MLDs suggested that listeners benefit from interaural difference cues during noise dips for signals out of phase. Neither tonal nor speech MLDs differed significantly between younger and older participants.

Conclusion
Binaural processing of sentences revealed some age-related deficits in the use of interaural difference cues, whereas no deficits were observed for more simple detection or recognition tasks.
Shape Distribution of Magnetite Powders
Authors: Johnson Clark E. , Brown William Fuller 
Published: March 2008

The shape distribution curves of single-domain magnetite powders calculated from magnetic data do not agree with those observed in the electron microscope. The Stoner-Wohlfarth theory, from which the magnetic unaveraging process was derived, ignores magnetocrystalline anisotropy. This may be one of the contributory causes to the lack of agreement. To establish this, the shape curves were measured magnetically on both acicular and equant magnetite powders at various temperatures. The magnetocrystalline anisotropy of magnetite is temperature dependent, changing from about −1 × 105 ergs/cc at room temperature to +1 × 105  ergs/cc at −165°C.
The magnetically calculated shape curves show some change with temperature; this indicates a contribution from the magnetocrystalline anisotropy.
Low-Loss Gyromagnetic Coupling through Single Crystal Garnets
Authors: DeGrasse R. W. 
Published: March 2008

This paper describes methods of synthesizing filters and gyrators using strong coupling of a small volume of ferrimagnetic material to an electromagnetic circuit. The small volume of material is treated as a lumped element resonator and it is shown that energy can be coupled through this resonator with low loss. The device uses the material for low-loss transmission of microwave energy.
The practical realization of devices using this principle depends upon strong coupling of the material to the circuit and the use of “low-loss” materials such as single crystal garnets.
The synthesis leads to the design of physically small electronically tunable filters, compact circulators and isolators. Such techniques may also be useful for the realization of low-frequency lumped element devices. Calculations and preliminary tests indicate that devices of this type will lead to the practical realization of solid state TR cells.
Harmonic Resonances in Small Ferrimagnetic Ellipsoids
Authors: Morgenthaler Frederic R. 
Published: March 2008

This paper considers the response of the magnetization of a small ferrimagnetic ellipsoid to spatially uniform rf magnetic fields of one or more frequencies. Only a few pertient cases can be considered in this short paper. The analysis is applicable to other excitations and a more complete report will be published elsewhere. Some of the work presented here duplicates that of Pippin [Proc. Inst. Radio Engrs. 44, 1054 (1956)], Jepsen, and others, but the approach to the problem is quite different and allows one to extend previous results, as well as to derive new ones.
The effects of symmetry planes and anisotropy will be considered as well as the permeability tensor for the general ellipsoid when modulation terms of the magnetization are neglected.
Ferromagnetic Resonance near the Upper Limit of the Spin Wave Manifold
Authors: Buffler C. R. 
Published: March 2008

Measurements of line widths of polycrystalline garnets as a function of frequency and temperature are reported. The variation of these parameters allows the uniform precessional mode to move above the k = 0 upper limit of the spin wave manifold so that this mode is no longer degenerate with the low k value spin wave states. When this occurs the line width undergoes a radical change, since these low k states can no longer take place in the relaxation process. When the uniform precession is thus “outside” the manifold, the behavior of the line width should be attributed to the theory of Clogston, Suhl, Walker, and Anderson. When the uniform precession is “inside”the manifold, the behavior is best described by the theory of Schlömann.
It is believed that the measurements reported indicate convincingly the utility of the spin wave analysis of ferromagnetic relaxation.
Ferromagnetic Resonance of Iron Whisker Crystals
Authors: Rodbell D. S. 
Published: March 2008

The ferromagnetic resonance absorption characteristics of iron single crystals (grown by K. W. DeBlois of this laboratory) have been examined between −196°C and 850°C. The crystals are of filamentary growth habit and are commonly known as whiskers. The selected crystals have 〈100〉 growth directions, and their square cross sections are bounded by {100} crystal planes. They are typically 10 μ on a side, but sizes ranging from 2 to 40 μ have been examined. Resonance absorption is observed using standard techniques with the dc magnetic field parallel to the length of the whisker. The microwave energy penetrates only a small fraction of the volume due to eddy current limitation. Two resonance modes may be observed. One is driven by the uniform microwave magnetic field, the other by its curl component. The curl mode is equivalent to resonance in a flat plane of infinite extent and no edge corrections are required. The uniform mode subject to an additional field arising from the uncompensated magnetic pole distributions at the specimen edges. After identification, the uniform mode is uninteresting because of distortions that probably result from the inhomogeneities of the edge demagnetizing field. The curl mode on the other hand exhibits a line shape and width that, in some cases, may be evaluated from first principles. The line width in these cases is accounted for almost entirely by exchange and conductivity effects, no phenomenological damping mechanism being required. Because other crystals of iron exhibit much broader resonance line widths, these results suggest that crystal perfection, particularly surfaces in the case of metals, may be the determining factor of ferromagnetic resonance line widths in bulk crystals.
The data yield for the spectroscopic splitting factor, g, a temperature and frequency independent value of 2.05±0.01. The exchange stiffness parameter, A, determined in a self-consistent way with this splitting factor, is 25±5×10−7 erg/cm at 20°C.
Theoretical and Experimental Analysis of the Ferromagnetic Explosively Shocked Current Pulse Generator
Authors: Johnson Jerome H. 
Published: March 2008

To most effectively utilize the potential capability of the ferromagnetic explosively actuated current generator one must understand the effect of variation of parameters upon the device output into a given load. This report presents theories of operation of the device, an approximate theoretical analysis of the effect of variation of the basic circuit and device parameters and a comparison of theory with experimental results.
Theoretical and experimental data are presented and compared for peak current versus circuit load inductance, device load coil turns, and magnetic core width (for a fixed thickness). There is a gratifying similarity between theoretically predicted and experimentally determined data.
Guiding criteria are given for an optimum ferromagnetic current pulse generator system.
Design of Automatic Recording Instruments for Magnetic Measurements in a Hot Cell
Authors: Byrnes W. S. , Crawford R. G. , Hall R. C. 
Published: March 2008

Two remotely controlled, automatic recording instruments have been designed and constructed for making magnetic measurements in a hot cell: A torque magnetometer for crystal anistropy measurements and a magnetostrictometer for magnetostriction measurements. The magnetometer automatically plots the torque exerted on a slowly rotating sample as a function of angular displacement with respect to the direction of the applied field. Its sensitivity is 2×103 erg/mv. The magnetostrictometer automatically plots strain as a function of applied field. Its maximum sensitivity is 0.2×10−6 in./in. mv.
Emphasis is placed on design features that enable these instruments to be operated by remote control. In this type of hot cell work, the handling of the samples to be tested requires the use of an expert operator at the manipulator. For this reason tools and jigs are described that compensate for operator inexperience. Such tools are an automatic screw driver, a vacuum pickup, jigs for bonding prewound strain gauges to the samples, etc.
In-Pile Measurements of Radiation Effects in Magnetic Materials
Authors: Alley R. E. 
Published: March 2008

Experiments have been performed at Brookhaven National Laboratory to determine the effects of nuclear reactor radiation upon the characteristics of ferrites and metallic magnetic materials. Photographs of 60 cycle hysteresis loops and bridge measurements of 1000 cycle inductance were made before irradiation, periodically during irradiation, and after reactor shutdown. The samples were irradiated for 12 days, resulting in an integrated fast flux of 1.6×1017 neutrons/cm2.
No permanent effect was observed in any ferrite. In-pile changes in ferrite properties are identified with changes due to temperature variations resulting from gamma ray absorption.
Permanent damage was observed in all metallic samples tested. Supermendur and Deltamax were least affected, showing increases of the order of 50% in coercive force and small decreases in initial permeability. Various samples of 4–79 Mo-Permalloy were affected differently, but all showed change in shape of hysteresis loop, several hundred percent increase in coercive force, and about 80% decrease in initial permeability. Supermalloy was most damaged by radiation, showing marked effects after 24 hr, and progressively greater effects throughout the exposure period.
Reversible, Diodeless, Twistor Shift Register
Authors: Bobeck Andrew H. , Fischer Robert F. 
Published: March 2008

A twistor shift register has been built and operated successfully. The design utilizes interaction effects which exist between magnetized regions on a magnetic wire. Only a single magnetic wire is required for a complete register. The information is stored as magnetically polarized zones which can be moved along the wire by means of a five phase pulse source.
No diodes are required. Therefore, drive powers can be greatly decreased since the only threshold consideration is the magnetic material itself. Bi-directional operation is easily secured. The upper frequency limit has not been established; however, a several hundred kilocycle bit rate should be possible. Physically, the register could be made of no more than magnetic and copper wire. This should make fabrication considerably cheaper than conventional shift registers.
Operating Characteristics of a Thin Film Memory
Authors: Raffel Jack I. 
Published: March 2008

An experimental prototype memory with 32 ten bit words has been designed, built, and tested. Circular spots 116 in. in diameter about 600 A thick are used. These are evaporated on two pieces of glass each comprising a 16×16 spot array. An operating cycle time of less than one-half microsecond appears possible.
The circuitry for driving and sensing is transistorized and the memory uses external register selection from a core-diode matrix. Word selection is provided by a transverse field, and a digit winding conditions the information written by applying a longitudinal field in the “one” or “zero” direction.
Extension to sizes of the order of 1000 words is planned using these techniques. The memory constructed here will soon be installed in the control element of the TX-2 computer.