julilili42/papers huggingface dataset:
Concise Synthesis and Displacement Reactions of Model 3-(Alkylthio)- 6-chloro- and 2,6-Dichlorothieno[2,3-e][1,4,2]dithiazine 1,1-Dioxides
2011-07-01

A series of 3-(alkylthio)-6-chlorothieno[2,3-e][1,4,2]dithiazine 1,1-dioxides (7a - e) were prepared via interaction of deprotonated 2,5-dichlorothiophene-3-sulfonamide with carbon disulfide under reflux, followed by alkylation with alkyl halides. Employment of dimethyl sulfate afforded the isomeric 2-methyl-3-thione derivative 8 together with the expected 3-(methylthio) derivative 7a in a molar ratio of 1 : 4. Treatment of 7a or 10 with ethylamine, aniline or p-chloroaniline produced the corresponding N-ethyl- (or N-phenyl)-6-chlorothieno[2,3-e][1,4,2]dithiazine-3-amine 1,1-dioxides 3a - c. Likewise, interaction of 7a with methylhydrazine (or phenylhydrazine) gave the respective 3-(1-methylhydrazinyl or 2-phenylhydrazinyl) 1,1-dioxides 9a, b. Desulfonation of 6-chloro-3-(methylthio)thieno[ 2,3-e][1,4,2]dithiazine 1,1-dioxide (7a) with sulfuryl chloride produced 3,6-dichlorothieno[2,3- e][1,4,2]dithiazine 1,1-dioxide (10). The latter compound was used as a substrate for the preparation of N-alkyl- (or aryl)-6-chlorothieno[2,3-e][1,4,2]dithiazin-3-amine 1,1-dioxides 3a - c representing a new approach for the synthesis of similar derivatives. Compounds 7a - e showed modest to low antibacterial activity against E. coli and S. aureus.
Why Do Patients with Partial Epilepsy Improve Their IQ After Training to Self-Regulate Slow Cortical Potentials?
2011-07-01

In patients with epilepsy, not only seizures but also cognitive, emotional, and social functioning are of increasing interest in research (Kelley, Jacobs, &amp; Lowenstein, 2009). As a decrease in cognitive functions over the course of the illness is usually reported, we wanted to explore changes in Intelligence Scores observed after a neurofeedback treatment in patients with drug-resistant epilepsies. In a controlled study that compared the outcome of three different interventions (training to regulate slow cortical potentials, N=34; training to regulate breath rate and the amount of carbon dioxide in the end tidal volume of the exhaled air, N=11; modification of drug regime, N=25), pre- and postmeasurements of a short version of the Wechsler Intelligence Scale were applied. The interval between the two assessments was more than 12 months, with a mean of 61 weeks. Mean age of the patients was 35, with a range from 17 to 57. The highly significant 7-point increment of IQ only after training of slow cortical potentials was not related to clinical (e.g., seizure reduction) or neuropsychological (e.g., attention and memory) variables. Instead, it was related to psychophysiological measures: IQ change was inversely related to the Latency of the P300 component of event-related brain potentials and directly related to the Latency of the P2 component and the increase of N2 Amplitude during training. We conclude that regulation training of slow cortical potentials improves IQ in patients with refractory partial epilepsy, which might be related to an improved ability for controlled allocation of cognitive resources.
P4‐062: Classical conditioning of the BOLD signal as a paradigm for basic BCI communication in Alzheimer patients
2011-07-01

Background Alzheimer patients express their need of social interaction even when their communication abilities are highly impaired. (Mayhew et al., 2001). Brain-computer interfaces (BCI), already used with severely paralyzed patients, may be adapted for communicating with Alzheimer patients by shifting the paradigm from instrumental-operant learning to classical conditioning (Birbaumer, 2006), e.g. by associating “yes” thinking to a positive emotion and “no” thinking to a negative emotion. We designed an fMRI-based BCI setting aimed at conditioning subjects to associate positive and negative emotional stimuli with respectively congruent and incongruent word pairs, in view of a BCI application for basic yes/no communication. Methods fMRI was performed on 6 healthy subjects during a classical conditioning session, comprising the phases of habituation, acquisition and extinction. The unconditioned stimuli consisted of a positive (baby laughter) and negative (scream) emotional sound. The conditioned stimuli, presented aurally, were congruent (e.g. “animal-elephant”) and incongruent (e.g. “animal-Germany”) word pairs. During the conditioning acquisition phase, congruent word pairs were associated to the baby laughter and incongruent word pairs were associated to the scream. A linear Support Vector Machine was implemented to classify the BOLD signal corresponding to congruent and incongruent word pairs. To investigate the relative importance of distinct brain areas in decoding different brain states, feature vectors from the frontal cortex were also used as input to build a separate classifier. Results Participants rated in the Self Assessment Manikin (SAM) the scream and the laughter as having, respectively, negative and positive valence. Moreover, the scream was associated to higher arousal compared to the baby laughter. Classification of the BOLD signal as a response to the congruent and incongruent word pairs immediately followed by the emotional unconditioned stimuli showed above chance level performance (57-64%) in one subject, while the performance was chance level on the remaining subjects (44-56%). Conclusions We presented a possible paradigm for basic yes/no communication, based on the conditioning of BOLD signal by the repeated association of emotional and semantic stimuli. The performance of the classifier by feature selection needs to be improved before being tested with Alzheimer patients. Future developments also comprise an online implementation of the system.
Fiscal News and Macroeconomic Volatility
2011-07-01

This paper analyzes the contribution of anticipated capital and labor tax shocks to business cycle volatility in an estimated New Keynesian DSGE model. While fiscal policy accounts for 12 to 20 percent of output variance at business cycle frequencies, the anticipated component hardly matters for explaining fluctuations of real variables. Anticipated capital tax shocks do explain a sizable part of inflation and interest rate fluctuations, accounting for between 5 and 15 percent of total variance. In line with earlier studies, news shocks in total account for 20 percent of output variance. Further decomposing this news effect, we find that it is mostly driven by stationary TFP and non-stationary investment-specific technology.
A wide-range time-digital converter
2011-07-01

A time-digital converter is designed for studying events with long delay times between events, which are correlated in time. The measured time interval range is 276 μs, the converter channel width is 67.4 ns, the integral nonlinearity is ≤1%, and the differential nonlinearity is ≤4%. The converter is made in the CAMAC standard.
IC‐P‐081: Near‐infrared spectroscopy: a reliable tool to assess cortical changes in Alzheimer's disease and their progression over time
2011-07-01

The technique of Near-Infrared Spectroscopy (NIRS) is a non-invasive optical method allowing the in vivo measurement of brain activation via changes in the concentration of oxy- [O2Hb] and deoxygenated [HHb] haemoglobin in the cerebral cortex. Neuroimaging studies show widespread activation deficits in patients suffering from Alzheimer's disease (AD) during tasks targeting the visuo-spatial and executive domains located in prefrontal and parietal areas. Using NIRS the present study assessed changes in prefrontal and parietal oxygenation in AD patients and healthy controls and their progression over a one-year interval. 71 Patients suffering from AD and 68 elderly healthy controls were measured during two versions of a verbal fluency task (VFT, letter and category) and a line orientation task (LO) using 44-channel (VFT) and 52-channel (LO) fNIRS. 14 patients and 49 controls completed a follow-up measurement after one year. During the letter version of the VFT and the LO AD-patients displayed a reduced activation pattern in the prefrontal (VFT) and the parietal cortex (LO) as compared to healthy controls. Increases in O2Hb in parietal regions correlated with prefrontal activity in AD-patients but remained independent in healthy controls. Prefrontal activation decreased significantly over the one year interval in AD-patients. Healthy controls showed no changes at follow up. Activation decreases in the prefrontal cortex were correlated with the decrease of the MMSE score, with greater decrease indicating lower MMSE score at the follow-up. fNIRS seems to be a well suited instrument to measure disease related changes in the cortex of AD patients and their progression over time. Considering the fact that we did not observe any changes in healthy controls without any cognitive decline fNIRS could be a promising device to be used in prospective studies of AD and other dementias.
Formation and Orbital Evolution of Planets
2011-07-01

Abstract The formation of planetary systems is a natural byproduct of the star formation process. Planets can form inside the protoplanetary disk by two alternative processes. Either through a sequence of sticking collisions, the so-called sequential accretion scenario, or via gravitational instability from an over-dense clump inside the protoplanetary disk. The first process is believed to have occurred in the solar system. The most important steps in this process will be outlined. The observed orbital properties of exoplanetary systems are distinctly different from our own Solar System. In particular, their small distance from the star, their high eccentricity and large mass point to the existence of a phase with strong mutual excitations. These are believed to be a result of early evolution of planets due to planet-disk interaction. The importance of this process in shaping the dynamical structure of planetary systems will be presented.
P3‐482: Alzheimer's disease patients’ cognitive functions are enhanced following a new non‐invasive non‐pharmacological treatment
2011-07-01

Alzheimer's disease (AD) is associated with pronounced decline in multiple cognitive functions and is well documented. Studies have revealed various correlates in the brain. However, what may trigger such changes remains to be explored. A leading hypothesis is that cortical plasticity-associated mechanisms become increasingly less efficient with the progress of the disease. There is evidence in literature that, transcranical magnetic stimulation (TMS), a non-invasive and painless method of brain stimulation, if applied repetitively (rTMS), induces a modulation in brain cortical excitability. An additional non-pharmacological treatment for AD is cognitive training, but a smaller effect was reported in literature compared with drug treatments for either one. TMS, if applied to various brain regions of mild to moderate AD patients, in conjunction with cognitive training may have a synergistic effect. Recently such initial results have been reported (NICE, Israel, Bentwich et al. J Neur Trans Jan 2011). Cognitive training was specifically designed to fit with the known cognitive functions of the relevant treated brain sites, which are known to be affected by AD. The treated brain regions included six different brain regions, which are involved with language, memory, orientation and visual compilation. The achieved ADAS-Cog average improvement after 6 weeks of treatment was significant compared to control. This combined method seems to be efficacious and safe and is currently tested in numerous clinical trials. Long-term potentiation is possibly the underlying mechanism of the above new technology and its synergistic effect, probably gives rise to greater connectivity and efficacy on a given learning task.
Influence of Rotation Velocity Gradient on Line Profiles of Accretion Discs of CVs
2011-07-01

Abstract We show the influence of the Keplerian velocity shear on the line profiles of cataclysmic variable discs. The complete disc structure is taken into account. The radial disc structure follows the alpha disc approximation. Based on this assumption, the vertical structure is computed using the detailed non-LTE code AcDc . The obtained opacities and source functions are interpolated in the 2D grid, where the radiative transfer is calculated with the inclusion of the velocity field gradient.
P1‐095: Stem cell factor plasma levels predict cognitive decline in Alzheimer's disease patients
2011-07-01

Alzheimer's disease (AD) is the most common cause of cognitive decline in the elderly and is characterized by massive neuronal cell loss in the brain. Stem cell factor (SCF) is a hematopoietic growth factor (HGF) that promotes neuroprotective effects and supports neurogenesis in the brain. Decreased SCF plasma levels have been described in AD patients. Whether SCF plasma levels are also associated with the rate of cognitive decline in AD patients is poorly understood so far. Forty AD outpatients from the memory clinic at the University Hospital of Psychiatry and Psychotherapy Tübingen were included in the study. All the patients were followed up prospectively and were re-examined clinically 1 year later (range 11-13 months). Among AD patients, 28 patients showed a slow cognitive decline (decrease of MMSE score = 4/year) and 12 patients displayed a fast cognitive decline (decrease of MMSE score > 4/year). Soluble SCF plasma levels were measured by ELISA. In the present study we demonstrate that SCF plasma levels are significantly decreased in AD patients with fast cognitive decline compared to AD patients with slow cognitive decline (fast vs. slow cognitive decline: mean±SD: 1051.1±178.7 vs. 1237.9±274.2 pg/ml; p = 0.037) and show a significant correlation with the rate of cognitive decline during 1 year follow-up (r = 0.315; p = 0.048). Multivariate analysis revealed that SCF plasma levels (B = 0.279; p = 0.041), age (B = 0.393; p = 0.006) and MMSE scores (B = −0.420;p = 0.002) at baseline were independent predictors for the rate of cognitive decline. These results suggest that lower SCF plasma levels are associated with a higher rate of cognitive decline in AD patients. Thus, treatment strategies increasing SCF plasma levels could be useful for delaying the progression of AD. Further longitudinal studies are necessary to elucidate the kinetics and the potential role of plasma SCF as a surrogate marker of disease progression and treatment target in AD patients.
P3‐088: Vagus somatosensory‐evoked potentials: a non‐invasive diagnostic possibility for patients with mild cognitive impairment?
2011-07-01

Alzheimer's Dementia (AD) affects widespread areas in all parts of the brain. AD-typical alterations could be revealed in brainstem by neuropathological methods, also in the Nuclei of the N. vagus. It is not known, whether these changes can also be observed in the state of mild cognitive impairment (MCI). Only a few diagnostic procedures considered the function of brainstem in AD. Vagus-somatosensory evoked potentials (VSEP) are far-field potentials from the brainstem and could be a representation of the function of the brainstem. Furthermore, the measurement is simply applicable for psychiatric patients. 13 patients with AD, 12 with MCI and 27 age- and gender-matched healthy controls were investigated by stimulating the cutane branch of the N. vagus at the inner side of the tragus of the right ear with an electrical square impulse of 0.1 msec duration. The response was bipolarly recorded from the electrode positions C3-F3, C4-F4, Fz-F3 and Fz-F4 of the international 10-20-system. After averaging, the VSEP could be defined by the first maximum (P1), the following minimum (N1) and the second maximum (P2). In the electrode wiring FZ-F4, a clear grading from HC over MCI to AD could be found for the VSEP latencies with significant results between HC and AD (N1: p=0.006, P2: p=0.001) and significant results in the linear trend test (P1: p=0.006, N1: p=0.005, P2: p=0.001), but no significant differences between HC and MCI resp. MCI and AD. In C4-F4, significant differences between AD and HC (p=0.009) as well as between MCI and HC (p=0.001) could be shown for P1, but no difference between the two groups of patients. As expected no potentials occurred on the left side of the head. The amplitudes of the VSEP are dispersed with no systematic link to the diagnoses of cognitive decline. VSEP is able to discriminate between cognitively declined patients and healthy controls with regard to the latencies of the potentials. The difference between MCI and AD reached no statistical significance, so further studies are necessary on the (diagnostic) specificity of the findings. The amplitudes of the potential have no diagnostic power.
P4‐226: Glial cell line‐derived neurotrophic factor in lithium‐treated patients with early Alzheimer's disease
2011-07-01

Preclinical and clinical studies gave evidence that lithium could be useful in the treatment of Alzheimer's disease (AD). One possible mechanism of action might be the induction of neurotrophins. Recently, we found a significant increase of brain-derived neurotrophic factor (BDNF) serum levels in AD patients treated with lithium and a significant decrease of ADAS Cog sum scores in comparison to placebo-treated patients. In another previous study we have shown that glial cell line-derived neurotrophic factor (GDNF) levels in cerebrospinal fluid (CSF) of patients with early AD are increased most probably due to an upregulated expression in CNS as an adaptive process of the impaired brain to enhance neurotrophic support at least in early stages of disease. Here we assessed the influence of a lithium treatment on GDNF serum and CSF concentrations in a subset of a greater sample recruited for a randomized, single-blinded, placebo-controlled, parallel-group multicenter 10-week study, investigating the efficacy of lithium treatment in AD patients. We found a significant negative correlation of lithium concentration in serum with GDNF concentration in CSF at the end of treatment and with the difference of GDNF concentration in CSF before and after treatment. However, we could not show a difference in GDNF concentrations between the patients after the treatment with lithium or placebo. The findings of the present investigation indicate that beneficial effects of the lithium treatment such as improvement of neurotrophic support by increase of BDNF might reduce the necessity of enhanced GDNF expression in the CNS in early AD.
(F)UV spectral analysis of 15 extremely hot, hydrogen-rich central stars of planetary nebulae
2011-07-01

Abstract We present results of a (F)UV spectral analysis of 15 hot, hydrogen-rich central stars of planetary nebulae (CSPNe) of DAO-type (A 7, A 31, A 35, A 39, NGC 3587, NGC 6720, NGC 6853, NGC 7293, PuWe 1, Sh 2-174) and O(H)-type (A 36, Lo 1, LSS 1362, NGC 1360, NGC 4361). The sample covers a wide range of parameters ( T eff ≈ 70–130 kK, log g = 5.4–7.4). It represents different stages of post-AGB evolution. The derived stellar parameters are crucial constraints for AGB nucleosynthesis and stellar evolutionary calculations. Detailed spectral analyses using fully line-blanketed NLTE model atmospheres including 23 elements from hydrogen to nickel are performed. Additional modeling of the ISM line absorption enables to unambigiously identify nearly all observed lines and to improve both, the photospheric as well as the ISM model.
IC‐P‐080: Prefrontal lateralization during a verbal fluency task predicts neuropsychological changes in healthy elderly controls: a fNIRS study
2011-07-01

Near-Infrared Spectroscopy (NIRS) is a non-invasive optical method measuring brain activation by assessing changes in the concentration of oxy- [O2Hb] and deoxygenated [HHb] haemoglobin in the cerebral cortex. During a verbal fluency task (VFT) healthy controls display a typical pattern of activation in prefrontal regions with a distinct lateralisation to the left dorso-lateral prefrontal cortex (DLPFC). This lateralisation decreases with age indicating compensatory processes. We expected the amount of lateralisation during the VFT to predict neuropsychological changes in healthy elderly controls over a one year interval. 44 elderly healthy controls (aged 55-82 years) were measured during two versions of a VFT (phonological and semantical) using 44-channel functional NIRS. MMST and DemTect were performed at the time of the fNIRS measurement and again after one year. During both versions of the VFT subjects displayed a typical activation pattern in the DLPFC with a distinct increase in O2Hb. Subjects’ lateralisation did not correlate with age. The amount of lateralisation during the letter version could account for a significant amount of the changes in MMST (16%) and DemTect (9%) after one year. Subjects displaying less distinct or no lateralisation showed a decrease in neuropsychological performance whereas subjects with a clearly lateralized activation did not change in MMST or DemTect. fNIRS seems to be a suitable tool for the study of long term changes in elderly subjects when assessing brain activation and cognitive decline. As alternations in oxygenation probably occur even before atrophy in affected brain regions, fNIRS could add to the development of methods for the early detection of mild cognitive impairment or Alzheimer's disease.
P2‐006: Correlation between loss of perfusion and vascular amyloidosis in transgenic mouse models of Alzheimer's Disease assessed with multi‐functional PET/MR
2011-07-01

In many neurodegenerative disorders physiological parameters of the brain like regional cerebral blood flow (rCBF) are altered and might play a critical role in both disease onset and progression. In this study we concentrated on rCBF measurements with [15O]H2O-PET and correlated the results with arterial spin labeling-MRT (ASL) in APPPS1- and in APP23 mice. Furthermore, we elaborated on amyloid plaques with [11C]PIB and compared the deposition pattern with high resolution gradient echo T1 (greT1) and spin echo T2 (seT2) measurements. APPPS1 and APP23 mice with respective littermate controls were injected intravenously with 7.2 ± 2.5 MBq [11C]PIB for measurement of amyloid plaque deposition (specific activity > 50GBq/μmol) and with 29.1 ± 5 MBq [15O]H2O for measurement of rCBF. In addition, 3D greT1, seT2 and ASL were acquired for each mouse. The images were analyzed using cortex and hippocampus as target regions and the cerebellum as internal reference with the SRTM and the Logan graphical analysis. ASL data were analyzed with an in house programmed Matlab routine using a simplified version of the Bloch equation. Furthermore, the animals were studied histopathologically. APP23 mice showed a significantly decreased rCBF at 16 months (tg: 159 ± 19 mL/min/100g, co: 196 ± 19 mL/min/100g; n = 5, p < 0.05) that was also significantly further decreasing with age in transgenic animals while littermate controls showed no impaired rCBF (18 months, tg: 135 ± 19 mL/min/100g, co: 193 ± 33 mL/min/100g; n = 5, p < 0.01). The regions with focally impaired perfusion colocalize with [11C]PIB binding and hypointense spots in both 3D greT1 and seT2 images representing vascular amyloid. In sharp contrast, aged APPPS1 mice (17 months old) did not show any changes in rCBF besides a specific [11C]PIB binding and also no hypointense spots in both T1 and T2 MR images. As APP23 mice show both vascular and parenchymal plaques while APPPS1 mice are confined to parenchymal deposits, we could clearly show that there is a strong correlation between vascular amyloidosis and loss of perfusion. This technique might be also transferred to the clinic to distinguish between vascular and neuritic type dementia.