Motor sequencing deficits in schizophrenia: A comparison with Parkinson's disease.

Motor abnormalities occur in schizophrenia (SZ) and may arise from striatal dysfunction. This study examined whether the pattern of performance on simple and complex motor abilities in SZ was similar to that of patients with Parkinson's disease (PD). Quantitative tests of speeded movement and motor and cognitive sequencing were used to assess 25 SZ, 16 PD, and 84 normal controls (NCs). Sequencing performance was also examined with motor rigidity taken into account. Compared with the NC group, the SZ and PD groups were impaired on measures of motor rigidity and motor sequencing. With rigidity accounted for, the SZ group was significantly more impaired than the PD group on motor sequencing; cognitive and motor processes contributed to the motor deficit. Cognitive sequencing performance predicted motor sequencing performance in PD but not SZ. Although both SZ and PD resulted in significant motor and cognitive sequencing deficits, the pattern and correlates of these deficits differ, suggesting that the affected neural systems underlying motor deficits in SZ are different from those involved in PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Structural brain correlates of verbal and nonverbal fluency measures in Alzheimer's disease.

This study examined the relationships between regional brain volumes and semantic, phonological, and nonverbal fluency in 32 participants with Alzheimer's disease (AD). Object but not animal semantic fluency correlated with frontal and temporal gray matter volumes. Phonological fluency was not significantly associated with any brain volume examined. Nonverbal fluency was selectively associated with bilateral frontal gray matter volumes. Hippocampal volumes, although markedly reduced in these patients, were not related to any of the fluency measures. Results lend evidence to the importance of the frontal lobes in the directed generation of nonverbal and verbal exemplars by AD patients. Furthermore, both left and right-hemisphere regions contribute to the generation of verbal and nonverbal exemplars. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A study of highwall mining panel stability

This study describes numerical work carried out to investigate the stability of a highwall mining panel using local mine stiffness (LMS) theory. This theory estimates whether any small change in the equilibrium state of the stress field in the mining region provokes a sudden release of energy or induces a large change in the geometry of the mine system. This study focuses solely on panel instability that may arise due to pillar crushing. Panel instability that may arise due to slip along pre-existing faults has not been considered.The major conclusion of the study is that the use of the LMS concept, leading to a calculation of a panel factor of stability (PFS), used in conjunction with a factor of safety (FoS), can provide added confidence to a highwall mining panel layout design.A wide range of sensitivity analyses was conducted to gauge the most significant factors (such as pillar width-to-height ratio, mass coal strength, host rock stiffness, and rock/coal interface properties, panel configuration, etc.) that would affect the highwall mining panel stability. The major finding is that a FoS value of about 1.2 is the critical level below which the PFS starts to decrease rapidly, so that the stability of the panel is threatened. This statement is true over the wide range of factors considered in this paper. However, the results of this study may not be directly applied outside these ranges of geomechanical parameters and panel geometries or for different analysis techniques. If the input parameters lie outside the ranges of this study, both the FoS and the PFS need to be calculated for the layout and the specific trend of the PFS versus the FoS be further established. Previous back-analyses undertaken in a number of highwall mining pits have found that a design FoS of less than 1.2 did not ensure even short-term stability (less than a year). One such example is included in this study.     

A prospective 4- to 5-year study of DSM-III-R hypochondriasis

BACKGROUND: Although hypochondriasis is generally thought to be a chronic and stable condition with a relatively low remission rate, this disorder remains understudied. METHODS: This is a 4- to 5-year prospective case-control study of DSM-III-R hypochondriasis. Medical outpatients meeting DSM diagnostic criteria for hypochondriasis completed an extensive research battery assessing hypochondriacal symptoms, medical and psychiatric comorbidity, functional status and role impairment, and medical care. A comparison group of nonhypochondriacal patients from the same setting underwent the same battery. Four to 5 years later, both cohorts were re-interviewed. RESULTS: One hundred twenty hypochondriacal and 133 nonhypochondriacal comparison patients were originally studied. Follow-up was obtained on 73.5% (n = 186) of all patients. At follow-up, the hypochondriacal sample was significantly (P<.001) less hypochondriacal and had less somatization (P<.001) and disability than at inception, but 63.5% (n = 54) still met DSM-III-R diagnostic criteria. When compared with the comparison group using repeated measures multivariate analysis of variance, these changes remained statistically significant (P<.0001). Changes in medical and psychiatric comorbidity did not differ between the 2 groups. When hypochondriacal patients who did and did not meet diagnostic criteria at follow-up were compared, the latter had significantly less disease conviction (P<.05) and somatization (P<.01) at inception, and their incidence of major medical illness during the follow-up period was significantly (P<.05) greater. CONCLUSIONS: Hypochondriacal patients show a considerable decline in symptoms and improvement in role functioning over 4 to 5 years but two thirds of them still meet diagnostic criteria. Hypochondriasis, therefore, carries a very substantial, long-term burden of morbidity, functional impairment, and personal distress.     

Extent, pattern, and correlates of remote memory impairment in Alzheimer's disease and Parkinson's disease.

Content and contextual memory for remote public figures and events was assessed with a modified version of the Presidents Test in patients with Alzheimer's disease (AD) or Parkinson's disease (PD). Contributions of executive functioning, semantic memory, and explicit anterograde memory to remote memory abilities were also examined. The AD group had temporally extensive deficits in content and contextual remote memory not accountable for by dementia severity. The PD group did not differ from the control group in remote memory, despite anterograde memory impairment. These results support the position that different component processes characterize remote memory, various mnemonic and nonmnemonic cognitive processes contribute to remote memory performance, and anterograde and remote memory processes are dissociable and differentially disrupted by neurodegenerative disease. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A profile of neuropsychological deficits in alcoholic women.

Neuropsychological deficits, most notable in executive, visuospatial, and functions of gait and balance, are detectable in alcoholic men even after a month of sobriety. Less well established are the severity and profile of persisting deficits in alcoholic women. The authors used an extensive test battery to examine cognitive and motor functions in 43 alcoholic women who were sober, on average, for 3.6 months. Functions most severely affected in alcoholic women involved visuospatial and verbal and nonverbal working memory processes as well as gait and balance. Areas of relative sparing were executive functions, declarative memory, and upper-limb strength and speed. The authors found that lifetime alcohol consumption was related to impairment severity on Block Design (Wechsler Adult Intelligence Scale--Revised, D. Wechsler, 1981) and verbal and nonverbal working memory, suggesting a dose effect of alcohol abuse. The alcohol-related deficits in working memory, visuospatial, and balance implicate disruption of prefrontal, superior parietal, and cerebellar brain systems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reenergizing the grid: greater regulatory, legislative certainty needed

The North American Electric Reliability Council's (NERC) new reliability standards are an important milestone for the council and the electric power industry. They clarify existing NERC reliability standards, and they create the foundation for adopting enforceable standards. The grid ensure that the nation's retail electricity customers enjoy reliable and affordable electricity service, and it enables the country's evolving wholesale electricity markets. To support both functions in the future, the grid will require more investment. The nation's shareholder-owned electric utilities recognize this need and are building transmission facilities. Even with this new spending, the continually growing demand for electricity, coupled with the expanding number of wholesale market transactions, means that more investment will be necessary. To encourage it, a number of regulatory and legislative policies should be adopted at both the federal and the state level to improve investor certainty and cost recovery.     

Selective cortical and hippocampal volume correlates of Mattis Dementia Rating Scale in Alzheimer disease

OBJECTIVE: To examine whether each of the 5 Mattis Dementia Rating Scale (DRS) scores related to magnetic resonance imaging-derived volumes of specific cortical or limbic brain regions in patients with Alzheimer disease (AD). DESIGN: Relations between DRS measures and regional brain volume measures were tested with bivariate and multivariate regression analyses. SETTING: The Aging Clinical Research Center of the Stanford (Calif) University Department of Psychiatry and Behavioral Science and the Geriatric Psychiatry Rehabilitation Unit of the Veterans Affairs Palo Alto Health Care System, Palo Alto, Calif. PATIENTS AND OTHER PARTICIPANTS: Fifty patients with possible or probable AD. Magnetic resonance imaging data from 136 healthy control participants, age 20 to 84 years, were used to correct brain volumes for normal variation arising from intracranial volume and age. MAIN OUTCOME MEASURES: The DRS scores and volumes of regional cortical gray matter and of the hippocampus. RESULTS: Memory scores of the patients with AD were selectively related to hippocampal volumes. Attention and construction scores were related to several anterior brain volume measures, with attention showing a significantly greater association to right than left hemisphere measures. Initiation/perseveration scores were not significantly correlated with any measure of regional gray matter volume, but performance was related to prefrontal sulcal widening, with a greater association with the left than right sulcal volume. CONCLUSIONS: Certain DRS subtests are predictably correlated with selective regional brain volumes in AD. The specific relation between memory and hippocampal volumes and the nonsignificant relations between memory and regional cortical volumes suggest a dissociation between cortical and hippocampal contributions to explicit memory performance.     

Garlic powder and wheat bran as fillers: Their effect on the physicochemical properties of edible biocomposites

Biocomposites with two different fillers, garlic and wheat bran, were studied. They were based on cassava starch and contained glycerol as a plasticizer and potassium sorbate as an antimicrobial agent and were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and infrared spectroscopy (IR). The mechanical performance at room and lower temperatures was also studied.SEM micrographies of fractured surfaces of the wheat bran composite films showed some ruptured particles of fiber while fibrils of garlic on the order of nanometers were observed when garlic composite films were studied.Mechanical tests, at room temperature, showed that the addition of wheat bran led to an increment in the storage modulus (E′) and hardening and a decrease in Tan δ, while the garlic composite showed a diminishing in the E′ and hardening and did not produce significant changes in Tan δ values when compared with systems without fillers (matrix). In the range between ?90 °C and 20 °C, all the materials studied presented two peaks in the Tan δ curve. In the case of the wheat bran composite, both relaxation peaks shifted slightly to higher temperatures, broadened and diminished their intensity when compared with those of the matrix; however garlic composite showed a similar behavior to the matrix.DSC thermograms of aqueous systems showed a slight shift of gelatinization temperature (T_{gelatinization}) to higher values when the fillers were present. Thermograms of films showed that both, garlic and wheat bran composites, had a lower melting point than the matrix.IR data indicated that interaction between starch and fillers determined an increase in the availability of hydroxyl groups to be involved in a dynamic exchange with water.