julilili42/papers huggingface dataset:
Imaging and Spectroscopy of Defect Luminescence and Electron−Phonon Coupling in Single SiO2 Nanoparticles
2009-08-04

Silicon nanocrystals were synthesized by CO(2) laser pyrolysis of SiH(4). The fresh silicon nanopowder was oxidized in water to obtain SiO(2) nanoparticles (NPs) exhibiting strong red-orange photoluminescence. Samples of SiO(2) NPs embedded in low concentration in a thin polymer layer were prepared by spin-coating a dedicated solution on quartz cover slides. Using an argon ion laser at 488 nm with higher-order laser modes (azimuthally and radially polarized doughnut modes) for excitation, the three-dimensional orientation of the nanoparticles' transition dipole moment was investigated in a confocal microscope. The linear transition dipole moment was found to be rather stable and randomly oriented. However, dynamical effects such as fluorescence intermittency and transition dipole moment flipping could also be observed. The spectral analysis of single SiO(2) NPs revealed double-peak spectra consisting of a narrow zero-phonon line and a broader phonon band being associated with the excitation of longitudinal optical phonons in the SiO(2) NP.
Fragmented Many-Body Ground States for Scalar Bosons in a Single Trap
2009-08-05

We investigate whether the many-body ground states of bosons in a generalized two-mode model with localized inhomogeneous single-particle orbitals and anisotropic long-range interactions (e.g., dipole-dipole interactions) are coherent or fragmented. It is demonstrated that fragmentation can take place in a single trap for positive values of the interaction couplings, implying that the system is potentially stable. Furthermore, the degree of fragmentation is shown to be insensitive to small perturbations on the single-particle level.
Emerging gene-directed anti-tumor strategies against human hepatoblastoma
2009-08-05

Background: Despite impressive improvements of treatment results in children suffering from hepatoblastoma (HB), advanced tumor stages still produce unsolved problems for treating physicians. HB tumors are commonly treated following trial regimens, which have been set up by multicenter study groups based on an ongoing treatment evaluation. Recently, treatment outcomes have reached a phase of stagnation and currently alternative treatment options are under investigation. Gene-directed anti-HB treatment approaches have been newly identified as promising option in this regard. Objective: To optimize and extend gene directed treatment strategies in order to improve treatment results of advanced stage HB. Methods: A review of the literature on genetic alterations in HB and of the current state of experimental gene-directed treatment approaches against HB. Results/conclusion: HB seems to be a suitable target for gene-directed treatment approaches. Further development of gene transfer systems and HB-specific strategies will lead to new alternatives for the treatment of this malignancy.
Age constraints on faulting and fault reactivation: a multi-chronological approach
2009-08-06

Movement within the Earth’s upper crust is commonly accommodated by faults or shear zones, ranging in scale from micro-displacements to regional tectonic lineaments. Since faults are active on different time scales and can be repeatedly reactivated, their displacement chronology is difficult to reconstruct. This study represents a multi-geochronological approach to unravel the evolution of an intracontinental fault zone locality along the Danube Fault, central Europe. At the investigated fault locality, ancient motion has produced a cataclastic deformation zone in which the cataclastic material was subjected to hydrothermal alteration and K-feldspar was almost completely replaced by illite and other phyllosilicates. Five different geochronological techniques (zircon Pb-evaporation, K–Ar and Rb–Sr illite, apatite fission track and fluorite (U-Th)/He) have been applied to explore the temporal fault activity. The upper time limit for initiation of faulting is constrained by the crystallization age of the primary rock type (known as “Kristallgranit”) at 325 ± 7 Ma, whereas the K–Ar and Rb–Sr ages of two illite fractions &lt;2 μm (266–255 Ma) are interpreted to date fluid infiltration events during the final stage of the cataclastic deformation period. During this time, the “Kristallgranit” was already at or near the Earth’s surface as indicated by the sedimentary record and thermal modelling results of apatite fission track data. (U–Th)/He thermochronology of two single fluorite grains from a fluorite–quartz vein within the fault zone yield Cretaceous ages that clearly postdate their Late-Variscan mineralization age. We propose that later reactivation of the fault caused loss of helium in the fluorites. This assertion is supported by geological evidence, i.e. offsets of Jurassic and Cretaceous sediments along the fault and apatite fission track thermal modelling results are consistent with the prevalence of elevated temperatures (50–80°C) in the fault zone during the Cretaceous.
Identification of the UBP1 Locus as a Critical Blood Pressure Determinant Using a Combination of Mouse and Human Genetics
2009-08-06

Hypertension is a major health problem of largely unknown genetic origins. To identify new genes responsible for hypertension, genetic analysis of recombinant inbred strains of mice followed by human association studies might prove powerful and was exploited in our current study. Using a set of 27 recombinant BXD strains of mice we identified a quantitative trait locus (QTL) for blood pressure (BP) on distal chromosome 9. The association analysis of markers encompassing the syntenic region on human chromosome 3 gave in an additive genetic model the strongest association for rs17030583 C/T and rs2291897 G/A, located within the UBP1 locus, with systolic and diastolic BP (rs17030583: 1.3+/-0.4 mmHg p<0.001, 0.8+/-0.3 mmHg p = 0.006, respectively and rs2291897: 1.5+/-0.4 mmHg p<0.001, 0.8+/-0.3 mmHg p = 0.003, respectively) in three separate studies. Our study, which underscores the marked complementarities of mouse and human genetic approaches, identifies the UBP1 locus as a critical blood pressure determinant. UBP1 plays a role in cholesterol and steroid metabolism via the transcriptional activation of CYP11A, the rate-limiting enzyme in pregnenolone and aldosterone biosynthesis. We suggest that UBP1 and its functional partners are components of a network controlling blood pressure.
Imaging of Order Parameter InducedπPhase Shifts in Cuprate Superconductors by Low-Temperature Scanning Electron Microscopy
2009-08-07

Low-temperature scanning electron microscopy (LTSEM) has been used to image the supercurrent distribution in ramp-type Josephson junctions between Nb and either the electron-doped cuprate Nd_{2-x}Ce_{x}CuO_{4-y} or the hole-doped cuprate YBa_{2}Cu_{3}O_{7}. For zigzag-shaped devices in the short junction limit the critical current is strongly suppressed at zero applied magnetic field. The LTSEM images show that this is due to the Josephson current counterflow in neighboring 0 and pi facets, which is induced by the d_{x;{2}-y;{2}} order parameter in the cuprates. Thus, LTSEM provides imaging of the sign change of the superconducting order parameter, which can also be applied to other types of Josephson junctions.
The lily‐of‐the‐valley fragrance receptor—potential in prostate cancer imaging
2009-08-07

Abstract BACKGROUND The early diagnosis of prostate cancer and its metastases still remains a great challenge. Recently, olfactory receptors have been found in healthy and malignant prostate tissue. If conjugated to a dye, olfactory receptor ligands would represent candidates for markers of not only olfactory cells but also prostate tissue. Such a conjugate would be of great value for the detection of prostate cancer metastases. METHODS We coupled sulforhodamine, a fluorescence dye, to undecylic aldehyde, the antagonist of the lily‐of‐the‐valley fragrance receptor. By using confocal laser scanning microscopy and flow cytometry we examined the uptake of this conjugate into various different human cell lines. One healthy prostate cell line, two different prostate carcinoma cell lines, and five other carcinoma cell lines were investigated. CD1 nude mice bearing human PC3 prostate carcinoma xenografts were injected with the conjugate. Rhodamine fluorescence of mouse organ frozen sections was evaluated by confocal laser scanning microscopy. RESULTS When comparing the seven human cell lines, the conjugate was preferentially taken up by the cytoplasm of healthy and malignant prostate cells. The mice showed high conjugate uptake into the xenografts, but much lower uptake into the mouse organs. After 3 hr of circulation, efflux could be observed in the xenograft sections. Xenograft touch prints confirmed in vivo intracellular accumulation. CONCLUSION This conjugate may be of potential value in the diagnosis of prostate cancer and its metastases. Prostate 69: 1599–1602, 2009. © 2009 Wiley‐Liss, Inc.
Spectroscopic Characterization and Conformational Properties of S‐(Fluoroformyl)‐O‐(acetyl) Thioperoxide and S‐(Fluoroformyl)‐O‐(trifluoroacetyl) Thioperoxide
2009-08-07

Abstract The conformational properties of FC(O)SOC(O)CH 3 and FC(O)SOC(O)CF 3 were studied by vibrational spectroscopy [IR (gas phase, Ar matrix), Raman (liquid phase)] and quantum chemical calculations (B3LYP and MP2 methods). For both compounds the syn ‐ gauche ‐ syn conformer with synperiplanar orientation of both carbonyl C=O bonds with respect to the S–O bond, and gauche orientation around the S–O bond ( C 1 symmetry) is the most stable structure [73(5) % for FC(O)SOC(O)CH 3 and 82(5) % for FC(O)SOC(O)CF 3 ]. For FC(O)SOC(O)CH 3 two more conformers are observed in the Ar‐matrix spectra, 18(5) % syn ‐ trans ‐ syn with trans orientation around the S–O bond [ φ (C–S–O–C) = 180°, C 2 symmetry] and 9(5) % anti ‐ gauche ‐ syn with the FC(O) group oriented anti with respect to the S–O bond. The experimental free energy differences for these most stable forms of FC(O)SOC(O)CH 3 are Δ G ° = G ° ( syn ‐ trans ‐ syn ) – G ° ( syn ‐ gauche ‐ syn ) = 0.83(17) kcal mol –1 and Δ G ° = G ° ( anti ‐ gauche ‐ syn ) – G ° ( syn ‐ gauche ‐ syn ) = 1.27(35) kcal mol –1 , respectively. These values are well reproduced by the B3YLP/aug‐cc‐pVTZ method (0.76 and 1.23 kcal mol –1 ), but not by the MP2 approximation (2.72 and 1.28 kcal mol –1 ) For FC(O)SOC(O)CF 3 only one more stable conformer, 18(5) % anti ‐ gauche ‐ syn , is observed. The experimental free energy difference between both rotamers of FC(O)SOC(O)CF 3 , Δ G ° = G ° ( anti ‐ gauche ‐ syn ) – G ° ( syn ‐ gauche ‐ syn ) = 0.90(17) kcal mol –1 , is reproduced very well by the B3YLP/6‐311++G** method (0.82 kcal mol –1 ) and reasonably well by B3LYP/aug‐cc‐pVTZ (1.17 kcal mol –1 ) and MP2/6‐31G* (1.23 kcal mol –1 ) calculations. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2009)
Contractual Relations and Organizational Structure in Franchising – Empirical Evidence from Germany
2009-08-07

In this paper, we employ a new dataset based on a sample of 123 franchise systems originating from Germany to empirically test hypotheses stemming from agency theory and capital scarcity considerations on the contractual relations and the organizational structure in franchising. We include proxies for the franchisor’s capital scarcity as well as for moral hazard on the franchisee’s and the franchisor’s side. Furthermore, we distinguish between initial and ongoing franchisor support. Our results indicate that agency models based on double moral hazard do explain the design of franchise contracts and the organizational structure in terms of the proportion of franchised outlets. We find that the incentive component of the franchise contract (the royalty rate) is not influenced by moral hazard on the franchisee’s side, but rather by moral hazard on the franchisor’s side. Furthermore, the proportion franchised is strongly influenced by moral hazard on the franchisee’s side. Hence, after providing incentives to outlet managers by turning them into franchisees, thereby granting them residual claimancy, the royalty rate mainly serves to ensure ongoing franchisor input. The franchisor’s capital scarcity influences the fixed fee in franchise contracts and the proportion of franchised outlets, thus supporting standard capital scarcity arguments.
Evaluation of stereoselective anticonvulsant, teratogenic, and pharmacokinetic profile of valnoctylurea (capuride): A chiral stereoisomer of valproic acid urea derivative
2009-08-08

Summary Purpose: The purpose of this study was to evaluate the stereoselective anticonvulsant activity, neurotoxicity, pharmacokinetics, and teratogenic potential of two stereoisomers of valnoctylurea (VCU), a central nervous system (CNS)–active urea derivative of valnoctic acid, which is a constitutional isomer of valproic acid (VPA). Methods: VCU stereoisomers (2S,3S)‐VCU and (2R,3S)‐VCU were synthesized. Their anticonvulsant activity was determined and compared to VPA and racemic‐VCU in rats utilizing the maximal electroshock seizure (MES) and the subcutaneous pentylenetetrazole (scMet) tests. Neurotoxicity was determined in rats using the positional sense test, muscle tone test, and gait and stance test. The induction of neural tube defects (NTDs) by VCU stereoisomers was evaluated in a mouse strain highly susceptible to VPA‐induced teratogenicity. The pharmacokinetics of VCU was studied in a stereoselective manner following intraperitoneal (i.p.) administration to rats. Results: (2S,3S)‐VCU and (2R,3S)‐VCU median effective dose ED 50 values were 29 mg/kg [95% confidence interval (CI) = 8–60 mg/kg] and 42 mg/kg (95% CI = 36–51 mg/kg) (MES) and 22 mg/kg (95% CI = 13–51 mg/kg) and 12 mg/kg (95%CI = 7–21 mg/kg) (scMet), respectively. (2S,3S)‐VCU was more potent and had a wider safety margin (p &lt; 0.05), defined as the protective index (PI = TD 50 /ED 50 ), at both the MES (PI &gt; 17) and scMet (PI &gt; 23) tests than racemic‐VCU or (R,S)‐VCU (PI = 2.8 and 9.9, respectively). VCU stereoisomers caused NTDs at doses &gt;4 times that of their anticonvulsant ED 50 values. At a dose of 112 mg/kg, (2R,3S)‐VCU was nonteratogenic and less embryotoxic than its stereoisomer (2S,3S)‐VCU. No stereoselective pharmacokinetics was observed following intraperitoneal dosing of racemic‐VCU to rats. VCU was mainly eliminated by metabolism with a half‐life of 2 h. Conclusions: VCU anticonvulsant activity and wide PI values make it a potential candidate for development as a new, potent antiepileptic drug (AED).
The physiological impact of the serum and glucocorticoid-inducible kinase SGK1
2009-08-10

The outlined recent findings advanced our understanding of the molecular regulation of SGK1 as well as the role of the kinase in renal physiology and the pathophysiology of renal disease and hypertension. Future studies using pharmacological inhibitors of SGK1 will reveal the utility of the kinase as a new therapeutic target.
Reversibility of symptoms in a conditional mouse model of spinocerebellar ataxia type 3
2009-08-10

Spinocerebellar ataxia type 3 (SCA3) is caused by the expansion of a CAG repeat tract that affects the MJD1 gene which encodes the ataxin-3 protein. In order to analyze whether symptoms caused by ataxin-3 with an expanded repeat are reversible in vivo, we generated a conditional mouse model of SCA3 using the Tet-Off system. We used a full-length human ataxin-3 cDNA with 77 repeats in order to generate the responder mouse line. After crossbreeding with a PrP promoter mouse line, double transgenic mice developed a progressive neurological phenotype characterized by neuronal dysfunction in the cerebellum, reduced anxiety, hyperactivity, impaired Rotarod performance and lower body weight gain. When ataxin-3 expression was turned off in symptomatic mice in an early disease state, the transgenic mice were indistinguishable from negative controls after 5 months of treatment. These results show that reducing the production of pathogenic ataxin-3 indeed may be a promising approach to treat SCA3, provided that such treatment is applied before irreversible damage has taken place and that it is continued for a sufficiently long time.
A relativistically smeared spectrum in the neutron star X-ray binary 4U 1705−44: looking at the inner accretion disc with X-ray spectroscopy
2009-08-10

Iron emission lines at 6.4-6.97 keV, identified with fluorescent K alpha transitions, are among the strongest discrete features in the X-ray band. These are therefore one of the most powerful probes to infer the properties of the plasma in the innermost part of the accretion disc around a compact object. In this paper, we present a recent XMM-Newton observation of the X-ray burster 4U 1705-44, where we clearly detect a relativistically smeared iron line at about 6.7 keV, testifying with high statistical significance that the line profile is distorted by high-velocity motion in the accretion disc. As expected from disc reflection models, we also find a significant absorption edge at about 8.3 keV; this feature appears to be smeared, and is compatible with being produced in the same region where the iron line is produced. From the line profile, we derive the physical parameters of the inner accretion disc with large precision. The line is identified with the K alpha transition of highly ionized iron, Fe xxv, the inner disc radius is R(in) = 14 +/- 2 R(g) (where R(g) is the Gravitational radius, GM/c2), the emissivity dependence from the disc radius is r-2.27 +/- 0.08, the inclination angle with respect to the line of sight is i = 39 degrees +/- 1 degrees. Finally, the XMM-Newton spectrum shows evidences of other low-energy emission lines, which again appear broad and their profiles are compatible with being produced in the same region where the iron line is produced.
Therapeutic Vaccination with an Interleukin-2–Interferon-γ-Secreting Allogeneic Tumor Vaccine in Patients with Progressive Castration-Resistant Prostate Cancer: A Phase I/II Trial
2009-08-11

Immunotherapy with whole cell cancer vaccines has been tested in various tumor types. This study investigated the safety profile and antitumor activity of an allogeneic prostate carcinoma cell line, LNCaP, expressing recombinant human interleukin-2 and human interferon-gamma. Thirty HLA-A*0201-matched patients with progressive, castration-resistant prostate cancer received four intradermal injections on days 1, 15, 29, and 92, and then every 90 days, as long as no tumor progression occurred. Three patients received a dose level of 7.5 million cells, and 27 patients received 15 million cells per injection. The primary study criteria were safety and the difference in prostate-specific antigen doubling time (PSA-DT), determined in the pretreatment phase (before the start of vaccination) and in the trial treatment phase (during vaccination). No dose-limiting or autoimmune toxicity was seen. During vaccination there was a significant prolongation of the PSA-DT compared with the prevaccination period (prolongation from 63 to 114 days; p < 0.01; intention to treat). In addition, results showed a period of PSA stabilization of at least 12 weeks, together with stable bone scans in 12 of 30 patients, and 3 patients sustained a >50% decrease in PSA versus baseline. The median overall survival time from first vaccination was 32 months (mean value, 34 months). Immune monitoring revealed T cell stimulation in the majority of patients. This vaccine strategy was found to be safe and well tolerated and was accompanied by prolongation of PSA-DT. The results of this trial warrant clinical development of this vaccine.
Differential Clinical Significance of Individual NKG2D Ligands in Melanoma: Soluble ULBP2 as an Indicator of Poor Prognosis Superior to S100B
2009-08-12

Abstract Purpose: Cytotoxic lymphocytes interact with human tumor cells via the activating immunoreceptor NKG2D, recognizing a variety of stress-associated MIC and ULBP surface molecules. However, tumors can escape from this immunosurveillance by shedding NKG2D ligands (NKG2DL), rendering the soluble products detectable in patients' sera. Experimental Design: To elucidate the clinical significance of NKG2DL diversity, we studied their expression on melanoma tissues and their presence as soluble molecules in sera from &amp;gt;200 melanoma patients and compared the latter with the well-established serum marker S100B. Results: Immunohistochemistry revealed a heterogeneous expression of MIC and ULBP2 molecules between and within melanoma metastases. Compared with MIC, ULBP2 was less frequently expressed. Accordingly, elevated levels of soluble ULBP2 (sULBP2) were detected in sera of melanoma patients less frequently than elevated levels of soluble MICA (sMICA), although both soluble NKG2DL (sNKG2DL) were significantly increased compared with sera of healthy controls (P &amp;lt; 0.0001). Strikingly, elevated concentrations of sULBP2, but not of sMICA, were strongly associated with disease progression (P &amp;lt; 0.0001) and tumor load (P = 0.0003). Elevated serum levels of either sNKG2DL correlated with reduced overall survival, albeit considerably stronger for sULBP2 (P &amp;lt; 0.0001) than for sMICA (P = 0.011). In early-stage (I-III) melanoma patients, only sULBP2 (P &amp;lt; 0.0001) but neither sMICA nor S100B revealed prognostic significance. Multivariate analysis identified sULBP2 (P = 0.0015) and S100B (P = 0.013) but not sMICA as independent predictors of prognosis. Conclusion: Our data reveal marked differences in the clinical significance of individual sNKG2DL. Only sULBP2 is an independent predictor of prognosis, the significance of which is superior to the well-established and widely used melanoma serum marker S100B. (Clin Cancer Res 2009;15(16):5208–15)
Decomposed but Parallel Processing of Two-Digit Numbers in 1st Graders
2009-08-12

It has been suggested that decomposed processing of two-digit numbers develops from sequential (left-to-right) to parallel with age (Nuerk et al ., 2004). However, task demands may have provoked sequential processing as a specific rather than a universal processing style. In the current study a standard unit-decade compatibility effect observed in two-digit number magnitude comparison indicated that first graders were already able to process the single digit magnitudes of tens and units separately and in parallel. Consequently, previous findings of sequential processing may be specific for stimulus characteristics in which such a processing style is useful. It is concluded that even first graders seem to be able to adapt their individual processing styles depending on stimulus properties. More generally, this suggests that the manner by which children process two-digit numbers is strategically adaptive rather than fixed at a particular developmental stage.