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Texas Business Review, January 1977
How Oil Supports Prosperity in Texas; El Paso Economic Profile; Construction Activity and the Tax Reform Act of 1976Bureau of Business Researc
Adiabatic Evolution for Systems with Infinitely many Eigenvalue Crossings
We formulate an adiabatic theorem adapted to models that present an
instantaneous eigenvalue experiencing an infinite number of crossings with the
rest of the spectrum. We give an upper bound on the leading correction terms
with respect to the adiabatic limit. The result requires only differentiability
of the considered spectral projector, and some geometric hypothesis on the
local behaviour of the eigenvalues at the crossings
Étude du Chrome Comme Liaison Métallique Antidiffusante Entre Uranium et Aluminium. EUR 413. = Study of Chrome as an Antidiffusing Metal Bond between Uranium and Aluminum. EUR 413.
Melanin-Concentrating Hormone (MCH): Role in REM Sleep and Depression.
The melanin-concentrating hormone (MCH) is a peptidergic neuromodulator synthesized by neurons of the lateral sector of the posterior hypothalamus and zona incerta. MCHergic neurons project throughout the central nervous system, including areas such as the dorsal (DR) and median (MR) raphe nuclei, which are involved in the control of sleep and mood. Major Depression (MD) is a prevalent psychiatric disease diagnosed on the basis of symptomatic criteria such as sadness or melancholia, guilt, irritability, and anhedonia. A short REM sleep latency (i.e., the interval between sleep onset and the first REM sleep period), as well as an increase in the duration of REM sleep and the density of rapid-eye movements during this state, are considered important biological markers of depression. The fact that the greatest firing rate of MCHergic neurons occurs during REM sleep and that optogenetic stimulation of these neurons induces sleep, tends to indicate that MCH plays a critical role in the generation and maintenance of sleep, especially REM sleep. In addition, the acute microinjection of MCH into the DR promotes REM sleep, while immunoneutralization of this peptide within the DR decreases the time spent in this state. Moreover, microinjections of MCH into either the DR or MR promote a depressive-like behavior. In the DR, this effect is prevented by the systemic administration of antidepressant drugs (either fluoxetine or nortriptyline) and blocked by the intra-DR microinjection of a specific MCH receptor antagonist. Using electrophysiological and microdialysis techniques we demonstrated also that MCH decreases the activity of serotonergic DR neurons. Therefore, there are substantive experimental data suggesting that the MCHergic system plays a role in the control of REM sleep and, in addition, in the pathophysiology of depression. Consequently, in the present report, we summarize and evaluate the current data and hypotheses related to the role of MCH in REM sleep and MD
Smoke Alarm Ownership in Relation to Socio-Economic Factors
This study focuses on smoke alarm ownership within Christchurch. Two different areas were selected, based on income levels. These two areas, Holmwood and Avon Loop, were then compared to determine if socio-economic factors impact on smoke alarm ownership. This study focused primarily on the relationships between smoke alarm ownership and location, income, education, and home ownership. Other topics discussed include the number of alarms per household, escape plans, people who smoke in the household, heating methods, reasons for non-purchase and other specific relationships that were uncovered during the study. The results between the two areas are significant for various reasons explained in this study
Влияние минеральных солей на продукцию антибиотиков феназинового ряда от культуры Pseudomonas aeruginosa
NKX2.1-Related Disorders: a novel mutation with mild clinical presentation.
Background: A highly variable phenotype characterized by thyroid, respiratory and neurological defects has been
reported in an already established group of disorders namely NKX2.1-related disorders. We describe here the case of
an infant with a novel mutation of the NKX2.1 gene characterized by mild clinical presentation.
Aim of the study was to elucidate the genotype-phenotype correlation in our patient.
Methods: We performed genetic analysis of the NKX2.1 gene in an infant with no neonatal respiratory distress and
near-normal results at neonatal screening test for congenital hypothyroidism, choreoathetosis, ataxia and delayed
independent walking.
Results: A novel mutation of the NKX2.1 gene has been identified, that is responsible for a mild framework of
congenital hypothyroidism and neurological symptoms.
Conclusions: The frequency of congenital hypothyroidism cases associated with NKX2.1 mutations is expected to be
higher in a subgroup of patients, selected according to the neurological presentation. In these patients the analysis of
NKX2.1 mutational status is recommended
Multimodal Comprehension in Left Hemisphere Stroke Patients
Hand gestures, imagistically related to the content of speech, are ubiquitous in face-to-face communication. Here we investigated people with aphasia’s (PWA) processing of speech accompanied by gestures using lesion-symptom mapping. Twenty-nine PWA and 15 matched controls were shown a picture of an object/action and then a video-clip of a speaker producing speech and/or gestures in one of the following combinations: speech-only, gesture-only, congruent speech-gesture, and incongruent speech-gesture. Participants’ task was to indicate, in different blocks, whether the picture and the word matched (speech task), or whether the picture and the gesture matched (gesture task). Multivariate lesion analysis with Support Vector Regression Lesion-Symptom Mapping (SVR-LSM) showed that benefit for congruent speech-gesture was associated with 1) lesioned voxels in anterior fronto-temporal regions including inferior frontal gyrus (IFG), and sparing of posterior temporal cortex and lateral temporal-occipital regions (pTC/LTO) for the speech task, and 2) conversely, lesions to pTC/LTO and sparing of anterior regions for the gesture task. The two tasks did not share overlapping voxels. Costs from incongruent speech-gesture pairings were associated with lesioned voxels in these same anterior (for the speech task) and posterior (for the gesture task) regions, but crucially, also shared voxels in superior temporal gyri (STG) and middle temporal gyri (MTG), including the anterior temporal lobe. These results suggest that IFG and pTC/LTO contribute to extracting semantic information from speech and gesture, respectively; however, they are not causally involved in integrating information from the two modalities. In contrast, regions in anterior STG/MTG are associated with performance in both tasks and may thus be critical to speech-gesture integration. These conclusions are further supported by associations between performance in the experimental tasks and performance in tests assessing lexical-semantic processing and gesture recognition
Quasi-equilibrium states in thermotropic liquid crystals studied by multiple quantum NMR
We study the nature of the quasiinvariants in nematic 5CB and measure their
relaxation times by encoding the multiple quantum coherences of the states
following the JB pulse pair on two orthogonal bases, Z and X. The experiments
were also performed in powder adamantane at 301 K which is used as a reference
compound having only one dipolar quasiinvariant. We show that the evolution of
the quantum states during the build up of the quasi-equilibrium state in 5CB
prepared under the S condition is similar to the case of adamantane and that
their quasi-equilibrium density operators have the same tensor structure. In
contrast, the second constant of motion, whose explicit operator form is not
known, involves a richer composition of multiple quantum coherences on the X
basis of even order, in consistency with the truncation inherent in its
definition. We exploited the exclusive presence coherences 4, 6, 8, besides 0
and 2 under the W condition to measure the spin-lattice relaxation time T_{W}
accurately, so avoiding experimental difficulties that usually impair dipolar
order relaxation measurement such as Zeeman contamination at high fields, and
also superposition of the different quasiinvariants. This procedure opens the
possibility of measuring the spin-lattice relaxation of a quasiinvariant
independent of the Zeeman and S reservoirs, so incorporating a new relaxation
parameter useful for studying the complex molecular dynamics in mesophases. In
fact, we report the first measurement of T_{W} in a liquid crystal at high
magnetic fields. The comparison of the obtained value with the one
corresponding to a lower field (16 MHz) points out that the relaxation of the
W-order strongly depends on the intensity of the external magnetic field,
similarly to the case of the S reservoir, indicating that the relaxation of the
W-quasiinvariant is also governed by the cooperative molecular motions.Comment: 7 figures. http://www.famaf.unc.edu.ar/series/AFis2005.ht
Perfusion lung scintigraphy for the diagnosis of pulmonary embolism: a reappraisal and review of the Prospective Investigative Study of Acute Pulmonary Embolism Diagnosis methods.
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