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The high-precision X-ray diffraction setup for work with diamond anvil cells (DACs) in interaction chamber 2 (IC2) of the High Energy Density instrument of the European X-ray Free-Electron Laser is described. This includes beamline optics, sample positioning and detector systems located in the multipurpose vacuum chamber. Concepts for pump-probe X-ray diffraction experiments in the DAC are described and their implementation demonstrated during the First User Community Assisted Commissioning experiment. X-ray heating and diffraction of Bi under pressure, obtained using 20 fs X-ray pulses at 17.8 keV and 2.2 MHz repetition, is illustrated through splitting of diffraction peaks, and interpreted employing finite element modeling of the sample chamber in the DAC.

Static compression experiments over 4 Mbar are rare, yet critical for developing accurate fundamental physics and chemistry models, relevant to a range of topics including modeling planetary interiors. Here we show that focused ion beam crafted toroidal single-crystal diamond anvils with ~9.0 μm culets are capable of producing pressures over 5 Mbar. The toroidal surface prevents gasket outflow and provides a means to stabilize the central culet. We have reached a maximum pressure of ~6.15 Mbar using Re as in situ pressure marker, a pressure regime typically accessed only by double-stage diamond anvils and dynamic compression platforms. Optimizing single-crystal diamond anvil design is key for extending the pressure range over which studies can be performed in the diamond anvil cell.

The behavior of the f-electrons in the lanthanides and actinides governs important macroscopic properties but their pressure and temperature dependence is not fully explored. Cerium with nominally just one 4f electron offers a case study with its iso-structural volume collapse from the γ-phase to the α-phase ending in a critical point (p C, V C, T C), unique among the elements, whose mechanism remains controversial. Here, we present longitudinal (c L) and transverse sound speeds (c T) versus pressure from higher than room temperature to T C for the first time. While c L experiences a non-linear dip at the volume collapse, c T shows a step-like change. This produces very peculiar macroscopic properties: the minimum in the bulk modulus becomes more pronounced, the step-like increase of the shear modulus diminishes and the Poisson's ratio becomes negative-meaning that cerium becomes auxetic. At the critical point itself cerium lacks any compressive strength but offers resistance to shear.

Using nonresonant Fe Kβ x-ray emission spectroscopy, we reveal that Sr substitution into CaFe2As2 decouples the Fe moment from the volume collapse transition, yielding a collapsed-tetragonal, paramagnetic normal state out of which superconductivity develops. X-ray diffraction measurements implicate the c-axis lattice parameter as the controlling criterion for the Fe moment, promoting a generic description for the appearance of pressure-induced superconductivity in the alkaline-earth-based 122 ferropnictides (AFe2As2). The evolution of Tc with pressure lends support to theories for superconductivity involving unconventional pairing mediated by magnetic fluctuations.

Behavioral and electrophysiological testing of olfactory function was performed in 33 normal human male and female subjects, 18-83 years of age. Acuity for odor identification and odor detection was verified by standard psychophysical tests. For evoked potential testing, a constant flow olfactometer provided odorant stimuli (amyl acetate) or air control stimuli that were presented to the right nostril by a nasal cannula at a flow rate of 5 l/min, duration of 40 msec and random interstimulus intervals of 6-30 sec. The behavioral tests revealed no significant difference between males and females, whereas increasing age was associated with a decline in performance on the odor identification test. No reproducible evoked potentials were recorded in response to the air control stimulus. Potentials to the odorant stimulus consisted of 4 components named P1, N1, P2 and N2. A significant correlation was found between P2 latency and odor identification test scores, suggesting a relationship between the generation of the P2 component and olfactory processing. P2 peak latency increased significantly with age at 2.5 msec/year. An age-related decline in N1-P2 interpeak amplitude was seen in male subjects. Topographic differences were seen in the P2 peak amplitude and the N1-P2 and P2-N2 interpeak amplitudes such that their amplitudes were greatest at Cz and Pz. On average, N1-P2 interpeak amplitudes were larger in the female subjects than in the male subjects, possibly revealing a hormonal influence on the olfactory event-related potential.

Quantitative scalp EEG from 32 channels and the cerebral glucose metabolic rate from the 32 underlying cortical positions as assessed by positron emission tomography (PET) with 18F-2-deoxyglucose (FDG) were obtained on 36 patients with mild to moderate senile dementia of the Alzheimer type and 17 age- and sex-matched normal control subjects. Subjects performed a verbal memory task during uptake of FDG. There were significant correlations between both delta amplitude and metabolic rate and memory performance during FDG uptake. Patients with Alzheimer's disease had significantly greater left temporal delta amplitude and lower glucose metabolic rates. Both EEG delta in microvolts and metabolic rate had similar diagnostic sensitivity, but PET had fewer false positives among normals. The left amygdala had the highest sensitivity and percent correct diagnosis of any brain area. Temporal lobe EEG delta activity showed higher correlations with hippocampal metabolic rate than metabolic rate directly under the electrode.

Hexane‐soluble derivatives of neodymium amide Nd‐(NMe2)3 such as 1 or the unsolvated heterometallic peralkyl compound 2 form in the reaction of MMe3 (M = Al, Ga) with 3. This provides a route to soluble lanthanide complexes with small ligands. (Formula Presented.) (Figure Presented.) Copyright © 1994 by VCH Verlagsgesellschaft mbH, Germany

Evoked potentials were recorded from olfactory bulb, piriform cortex and scalp in urethane anesthetized rats in response to brief odorant stimuli (amyl acetate, phenylethyl alcohol, eugenol) presented through a nasal cannula by means of a constant flow olfactometer. The effects of stimulus duration, nasal cannula position, flow rate, concentration and interstimulus interval were examined. The highest amplitude potentials were evoked by 10% amyl acetate at 20 ms duration, 1000 ml/min flow rate and a 60-s interstimulus interval with the stimulus delivered at the nares. Odorant evoked potentials from deep within the olfactory bulb consisted of a triphasic wave with major components at 60 ms (P60), 90 ms (N90) and 140 ms (P140) with the latter two reversing polarity close to the surface of the bulb. Potentials recorded from layer I of piriform cortex were of similar amplitude, but opposite in polarity to the deep olfactory bulb potentials. Recordings from the skin over the nose elicited waveforms of similar morphology to the deep olfactory bulb potentials, but one-quarter the amplitude and of opposite polarity The evoked potentials changed with repetitive stimulation The N90 component was not present initially and only appeared after several stimuli. The appearance of the N90 component depended on the integrity of the olfactory peduncle. Thus, olfactory evoked potentials to odorant stimuli reflect dynamic aspects of the encoding of olfactory information dependent on connections between olfactory bulb and piriform cortex. © 1992 Oxford University Press.

Resting 32-channel topographical measures of EEG slow activity were compared in 12 elderly controls and 12 patients with senile dementia of the Alzheimer type. The patients had higher amplitude delta and theta than controls, especially in the left temporal regions. This greater amount of low frequency EEG activity in the left temporal area is consistent with recent EEG, neuropsychological assessment, and positron emission tomography findings in SDAT patients. Five patients with mild-to-moderate dementia (as determined by the Folstein Mini-Mental State scale) primarily exhibited focal, abnormal slow activity in the left temporal regions. Seven patients with severe dementia exhibited increased slow activity across the head, which was still most abnormal in the left temporal regions.

BACKGROUND/AIMS: The recruitment of culturally diverse subject populations into research studies, particularly African-Americans (AA), has been the focus of intense interest by many groups. METHODS: In this paper, we present the methodology utilized to create a predominantly AA cohort for the longitudinal study of risk factors in Alzheimer's disease (AD). The underlying strategy was that of identifying geographically diverse clinical venues within South Carolina (SC) where large numbers of AA patients already come to seek medical care. RESULTS: This strategy was successful, although recruitment rates for AA subjects (43.4%) still fell below those for white subjects (70.3%; p = 0.0025). Subject characteristics of AA subjects that chose to enroll were not substantially different from those that declined to participate. The demographic characteristics of this cohort were largely similar to those of the SC Alzheimer Disease Registry, a population-based database. The problems of standardization of subject recruitment and assessment across diverse clinical venues are also addressed. CONCLUSION: The utilization of geographically diverse sites for research recruitment where minorities already receive medical care is one practical solution to the problem of minority participation in research. Multi-site recruitment to improve minority recruitment can be accomplished with acceptable standardization and inter-rater reliability. [ABSTRACT FROM AUTHOR]

The primary aim of this study was to determine if resistive training would increase muscle strength and power in cognitively impaired elderly people. The secondary aim was to assess whether resistive training influenced physical functional abilities. Eight men and women, age range 63-88 years, with a diagnosis of dementia (Mini Mental Status Exam scores that ranged from 13-20), attended and successfully and safely completed a group resistive training program held twice weekly for 12 weeks. In postversus pre-training comparisons, muscle strength and power were increased for the hip abductor/adductor (p < .01), shoulder press (p < .05), leg extension/curl (p < .01) and chest/back (p < .01) exercises. However, there were no measurable improvements of functional abilities, including balance, the timed chair stand, gait speed or the timed stair climb. This study demonstrates that it is feasible to engage elderly persons with dementia in a structured resistive training program with measurable improvements after 12 weeks in muscle strength and power but not functional abilities. [ABSTRACT FROM AUTHOR]

Background: Megestrol acetate (MA) has been used to stimulate weight gain in elderly populations, with the majority of the weight gain being adipose tissue. Because of the increased energy intake and adipose tissue accrual with MA, it may have a negative effect on circulating lipids. Thus, in this study we examined the effects of MA--alone and in combination with resistance training and/or testosterone replacement--on blood lipids.Methods: All subjects (n = 28) received MA and were randomly assigned to one of four groups: 1) placebo (P) injections, 2) resistance training and P (RT+P), 3) weekly injections of testosterone (T; 100 mg/week), or 4) RT and T (RT+T).Results: A significant time effect was observed for total cholesterol (p = 0.0006) and high density lipoprotein (HDL) cholesterol (p = .0003) with the mid and post time points being significantly lower than the pre time points for both variables. For the total cholesterol to HDL ratio, no significant differences between groups or over time (time effect: ) were observed. For triglycerides, there tended to be a time effect (p = .061), with the mid and post time points being lower than the pre time point; however, this effect was not statistically significant.Conclusions: Because it appears from our data that MA does not cause adverse blood lipid changes, the decision to use it should be based on other factors. [ABSTRACT FROM AUTHOR]

Background: Muscle power diminishes with increasing age and inactivity. The capacity for older adults to increase muscle power with resistance exercise has not been examined; therefore, we examined the influence of progressive resistance training (PRT) on muscle power output in 17 men and women aged 56-66 years, and compared their responses to 15 men and women aged 21-30 years.Methods: All subjects performed 12 weeks of PRT at a workload equivalent to 80% of the one repetition maximum (1RM). All training and assessments of 1RM and power were made on Keiser pneumatic resistance machines. Subjects performed five exercises, three sets per exercise, twice weekly. Muscle power was measured (isotonically) at resistances equivalent to 40, 60, and 80% of the 1RM, on the knee extension and arm pull machines.Results: All subjects increased arm pull power similarly at 40 and 60% of 1RM, independent of age or sex. There was not a significant increase in arm pull power at 80% of 1RM. Older and younger subjects also had similar absolute increases in leg extensor power at 40 and 60% of 1RM, but men responded with greater absolute gains than women at these percentages (p < .05). The increase in leg extensor power at 80% of 1RM was similar in all groups. Older and younger subjects increased strength similarly in all exercises except the left knee extension. Independent of age, men increased strength more than women in all exercises except the double leg press.Conclusions: These data demonstrate that individuals in their sixth decade can still improve muscle power (and strength); however, men may realize greater absolute gains than women. [ABSTRACT FROM AUTHOR]

Background: Very limited data suggest that meat consumption by older people may promote skeletal muscle hypertrophy in response to resistance training (RT). Objective: The objective of this study was to assess whether the consumption of an omnivorous (meat-containing) diet would influence RT-induced changes in whole-body composition and skeletal muscle size in older men compared with a lactoovovegetarian (LOV) (meat-free) diet. Design: Nineteen men aged 51-69 y participated in the study. During a 12-wk period of RT, 9 men consumed their habitual omnivorous diets, which provided approximately 50% of total dietary protein from meat sources (beef, poultry, pork, and fish) (mixed-diet group). Another 10 men were counseled to self-select an LOV diet (LOV-diet group). Results: Maximal strength of the upper- and lower-body muscle groups that were exercised during RT increased by 10-38% (P < 0.001), independent of diet. The RT-induced changes in whole-body composition and skeletal muscle size differed significantly between the mixed- and LOV-diet groups (time-by-group interactions, P < 0.05). With RT, whole-body density, fat-free mass, and whole-body muscle mass increased in the mixed diet group but decreased in the LOV- diet group. Type II muscle fiber area of the vastus lateralis muscle increased with RT for all men combined (P < 0.01), and the increase tended to be greater in the mixed-diet group (16.2 +/= 4.4 %) than in the LOV diet group (7.3 +/= 5.1 %). Type I fiber area was unchanged with RT in both diet groups. Conclusion: Consumption of a meat-containing diet contributed to greater gains in fat-free mass and skeletal muscle mass with RT in older men than did an LOV diet. Copyright (c) 1999 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

The capacity of older men and women to adapt to regularly performed exercise has been demonstrated by many laboratories. Aerobic exercise results in improvements in functional capacity and reduced risk of developing type II diabetes in the elderly. High-intensity resistance training (above 60% of the 1 repetition maximum) has been demonstrated to cause large increases in strength in the elderly. In addition, resistance training results in significant increases in muscle size in elderly men and women. Resistance training has also been shown to significantly increase energy requirements and insulin action of the elderly. We have recently demonstrated that resistance training has a positive effect on multiple risk factors for osteoporotic fractures in previously sedentary post-menopausal women. Since the sedentary lifestyle of a long-term care facility may exacerbate losses of muscle function, we have applied this same training program to frail, institutionalized elderly men and women. In a population of 100 nursing home residents, a randomly assigned high-intensity strength training program resulted in significant gains in strength and functional status. In addition, spontaneous activity, measured by activity monitors, increased significantly in those participating in the exercise program, while there was no change in the sedentary control group. The fact that significant muscle hypertrophy was seen in this population indicates that age does not decrease the capacity to adapt to a progressive resistance training program. Therefore, exercise may minimize or reverse the syndrome of physical frailty which is so prevalent among the oldest old.(ABSTRACT TRUNCATED AT 250 WORDS) [ABSTRACT FROM AUTHOR]

Objective: To determine how multiple risk factors for osteoporotic fractures could be modified by high-intensity strength training exercises in postmenopausal women.Design: Randomized controlled trial of 1-year duration.Setting: Exercise laboratory at Tufts University, Boston, Mass.Population: Forty postmenopausal white women, 50 to 70 years of age, participated in the study; 39 women completed the study. The subjects were sedentary and estrogen-deplete.Interventions: High-intensity strength training exercises 2 days per week using five different exercises (n = 20) vs untreated controls (n = 19).Main Outcome Measures: Dual energy x-ray absorptiometry for bone status, one repetition maximum for muscle strength, 24-hour urinary creatinine for muscle mass, and backward tandem walk for dynamic balance.Results: Femoral neck bone mineral density and lumbar spine bone mineral density increased by 0.005 +/- 0.039 g/cm2 (0.9% +/- 4.5%) (mean +/- SD) and 0.009 +/- 0.033 g/cm2 (1.0% +/- 3.6%), respectively, in the strength-trained women and decreased by -0.022 +/- 0.035 g/cm2 (-2.5% +/- 3.8%) and -0.019 +/- 0.035 g/cm2 (-1.8% +/- 3.5%), respectively, in the controls (P = .02 and .04). Total body bone mineral content was preserved in the strength-trained women (+2.0 +/- 68 g; 0.0% +/- 3.0%) and tended to decrease in the controls (-33+77 g; -1.2% +/- 3.4%, P = .12). Muscle mass, muscle strength, and dynamic balance increased in the strength-trained women and decreased in the controls (P = .03 to < .001).Conclusions: High-intensity strength training exercises are an effective and feasible means to preserve bone density while improving muscle mass, strength, and balance in postmenopausal women. [ABSTRACT FROM AUTHOR]