355 research outputs found

    Brainstem evaluation in children with primary nocturnal enuresis.

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    We investigated the brainstem integrity in children with primary nocturnal enuresis (PNE) using auditory brainstem responses (ABR), blink reflex and exteroceptive suppression of the masseter muscle. We examined 23 children with PNE (16 male, 7 female; mean age: 10.4 years) and 19 control subjects (11 male, 8 female; mean age: 11.8 years). ABR parameters such as wave latencies, amplitudes and interpeak latencies and blink reflex parameters such as R1 and R2 amplitude and latencies were not significantly different between the 2 groups. Although S2 parameters of the exteroceptive suppression of the masseter muscle were easily and completely obtained from the control subjects, in the PNE group S2 onset latency and duration were not recorded in 26% of the study children (n = 6) (P = 0.01). S2 duration time was significantly lowered in the enuretic group (left side: P = 0.001 and right side: P = 0.003). S2 duration time changes in the enuretic group supports a possible brainstem dysfunction in children with PNE.</p

    Nichtlokale Korrelation in kaonischen Systemen

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    Die Nichtlokalität von Quantensystemen steht im Mittelpunkt der heutigen Physik. Sie ergibt sich direkt aus dem Superpositionsprinzip. Sie ist eine Eigenschaft, die aus dem Wellencharakter von Quantenobjekten folgt. Die Nichtlokalität gibt uns Physikern noch immer einige Rätsel auf. So hat man durch statistische Messungen mit Hilfe der Bellschen Ungleichungen nachweisen können, dass die Nichtlokalität nicht etwa ein scheinbarer Effekt ist, der nur auf Unkenntnis der wahren Verhältnisse zurückzuführen ist, sondern zu realen Effekten, wie z.B. der Quantenteleportation, führt. Diese Arbeit untersucht die nichtlokalen Korrelationen in kaonischen Systemen in Lichte der zwei Gebiete, nämlich der Teilchen Physik und der Grundlagen der Quantenmechanik. Der erste Teil bringt eine Einführung in die neutralen Kaonen. Die Verletzung der CP- Symmetrie (charge, parity) ist für das Verständnis der Elementarteilchenphysik von entscheidender Bedeutung, insbesondere zur Erklärung des Materieüberschusses bei der Teilchen-Antiteilchen Erzeugung im frühen Universium. Durch das Experiment von Christensen, Cronin und Fitch (1964) [1] wissen wir, dass beim Zerfall der neutralen Kaonen die CP- Symmetrie verletzt wird und dies bedeutet, dass auf Grund des CPT Theorems auch die Zeitumkehr T verletzt ist. Weiters wird im ersten Teil auch der Regenerationseffekt der Kaonen abgeleitet. Im zweiten Teil werden die verschränkten Quantensysteme besprochen. Die Standard- Interpretation der Quantenmechanik geht davon aus, dass die quantenmechanische Beschreibung eines Systems im allgemeinen nur statistische Aussagen über einzelne Messungen ermöglicht. Im Jahre 1935 konstuierten Einstein, Podolsky und Rosen [2] unter gewissen Annahmen (insbesondere Lokalität) ein Beispiel, das die Existenz verborgener lokaler Parameter zeigen sollte; dieses Beispiel wird als EPR Paradoxon bezeichnet. 30 Jahre später zeigte Bell [3] in seiner berühmten Ungleichung für bestimmte Messwerte, dass die Annahmen des EPR Paradoxons im Widerspruch zur Quantenmechanik stehen. Diese Ungleichung wurde 1969 von Clauser, Horne, Shimony, und Holt (CHSH) [4] für reale Experimente angepasst. Neben der CHSH-Ungleichung gibt es zahlreiche weitere Ansätze zur Verletzung der Bellschen Ungleichung. Im folgenden werden die Ungleichungen für Zweiteilchensysteme vorgestellt; dies sind CH [5] (Clauser,Horne), Wigner [6], CHSH [4] und Eberhard [7] Ungleichungen. Der dritte Teil bringt die Verwendung der Bell Ungleichungen für neutrale Kaonensysteme. Wir haben die Bell Ungleichungen mit Regenerator durch den Vergleich zwischen dem lokalen Realismus und Quantenmechanik getestet [8]. Damit haben wir zwei spezielle Ungleichungen - CH und Eberhard - näher diskutiert [9, 10, 11]. Zum Schluss wurde ein Loophole für diese speziellen Ungleichungen überprüft [9]. Hatice Tataroglu, Wien 200

    Role of Glycogen Synthase Kinase (GSK) in temperature compensation of the Neurospora circadian clock

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    Circadian clocks are biological oscillators that allow organisms to accurately predict and adjust to the rhythmic changes in the environment which increases their fitness. These oscillators are found in every cell and have three fundamental properties: they are endogenous, entrainable and temperature compensated. The former two properties of the clock are well studied. However, it is currently unknown how clocks accurately keep the time independent of the ambient temperature, a phenomenon known as “temperature compensation”. This is particularly important for poikilothermic organisms that cannot control their body temperature and yet still have accurate circadian clocks. We used Neurospora crassa as a eukaryotic circadian clock model organism and showed that Glycogen synthase kinase (GSK) binds and specifically phosphorylates White Collar 1 (WC-1), which is the critical and rate-limiting positive element of the Neurospora clock. We found that these phosphorylations decrease the WC-1 stability in a temperature dependent manner. Our data completes the picture in our current understanding of temperature compensation of circadian clocks and shows that temperature compensation in Neurospora crassa is achieved by opposing functions of two kinases (GSK and CK2) on the positive (WCC) and negative (FRQ) elements of the clock, respectively. Since both kinases are well conserved among eukaryotes, it is also possible that this mechanism of temperature compensation is conserved among other eukaryotic circadian clocks

    Electrical characterization of MIS diode prepared by magnetron sputtering

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    TiO2 thin film has been prepared on n-type Si wafer to fabricate an Au/TiO2/n-Si (MIS) diode by RF magnetron sputtering technique. The current-voltage (I-V) and capacitance-voltage (C-V) measurements of the diode have been performed over a wide range of temperatures (240-400 K) and frequencies (10 kHz-1 MHz), respectively. From I-V measurements, an abnormal increase in the barrier height (Φb) and a decrease in the ideality factor (n) with increasing temperature have been observed. This temperature dependence has been attributed to the barrier in homogeneities by assuming a Gaussian distribution (GD) of barrier heights at metal/semiconductor (M/S) interface. Both the conventional and modified Richardson plot show linearity. The activation energy (Ea), Richardson constant (A*) and Φb value have been calculated from the slope and intercept of the linear region. The obtained Richardson constant value of 113.82 A. cm-2. K-2 is in close agreement with the known value of 112 A.cm-2. K-2 for n-Si. The interface state density (Nss) and series resistance (Rs) of the diode has been obtained from the I-V measurements. In addition, the Φb value was determined from C-2-V characteristics. The obtained results indicate that the MIS diode with TiO2 interfacial insulator layer can be used in many device applications

    How to Improve the Resolving Power of Compact Electrospray Ionization Ion Mobility Spectrometers

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    Every drift tube ion mobility spectrometer (IMS) has an optimum drift voltage to reach maximum resolving power. This optimum depends, among other things, on the temporal and spatial width of the injected ion packet and the pressure within the IMS. A reduction of the spatial width of the injected ion packet leads to improved resolving power, higher peak amplitudes when operating the IMS at optimum resolving power, and thus a better signal-to-noise ratio despite the reduced number of injected ions. Hereby, the performance of electrospray ionization (ESI)-IMS can be considerably improved. By setting the ion shutter opening time to just 5 μs and slightly increasing the pressure, a high resolving power RP> 150 can be achieved with a given drift length of just 75 mm. At such high resolving power, even a mixture of the herbicides isoproturon and chlortoluron having similar ion mobility can be well separated despite short drift length

    CRTC Potentiates Light-independent timeless Transcription to Sustain Circadian Rhythms in Drosophila

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    Light is one of the strongest environmental time cues for entraining endogenous circadian rhythms. Emerging evidence indicates that CREB-regulated transcription co-activator 1 (CRTC1) is a key player in this pathway, stimulating light-induced Period1 (Per1) transcription in mammalian clocks. Here, we demonstrate a light-independent role of Drosophila CRTC in sustaining circadian behaviors. Genomic deletion of the crtc locus causes long but poor locomotor rhythms in constant darkness. Overexpression or RNA interference-mediated depletion of CRTC in circadian pacemaker neurons similarly impairs the free-running behavioral rhythms, implying that Drosophila clocks are sensitive to the dosage of CRTC. The crtc null mutation delays the overall phase of circadian gene expression yet it remarkably dampens light-independent oscillations of TIMELESS (TIM) proteins in the clock neurons. In fact, CRTC overexpression enhances CLOCK/CYCLE (CLK/CYC)-activated transcription from tim but not per promoter in clock-less S2 cells whereas CRTC depletion suppresses it. Consistently, TIM overexpression partially but significantly rescues the behavioral rhythms in crtc mutants. Taken together, our data suggest that CRTC is a novel co-activator for the CLK/CYC-activated tim transcription to coordinate molecular rhythms with circadian behaviors over a 24-hour time-scale. We thus propose that CRTC-dependent clock mechanisms have co-evolved with selective clock genes among different species.ope

    Incidence of fibroblast growth factor receptor 3 gene (FGFR3) A248C, S249C, G372C, and T375C mutations in bladder cancer

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    Bladder cancer is the most frequent cancer of the urinary system. Fibroblast growth factor receptors (FGFR) belong to the tyrosine kinase family and have important roles in cell differentiation and proliferation and embryogenesis. FGFR3 is located on chromosome 4p16.3, and missense mutations of FGFR3 are associated with autosomal dominant human skeletal disorders and have some oncogenic effects. We examined the incidence of FGFR3 thanatophoric dysplasia mutations located in exon 7, A248C and S249C, and in exon 10, G372C and T375C, and their correlation with clinical-pathological parameters in bladder carcinoma patients. Fifty-six paraffin-embedded specimens of transitional cell carcinoma of the urinary bladder were included in this study. Analysis of FGFR3 thanatophoric dysplasia mutations located in exon 7, A248C and S249C, and in exon 10, G372C and T375C, was performed by PCR- restriction fragment length polymorphism (RFLP) analysis and DNA sequencing. FGFR3 thanatophoric dysplasia mutations located in exon 7, A248C and S249C, and in exon 10, G372C and T375C, were detected in 33 of the 56 patients (heterozygous mutant). Among the 56 transitional cell carcinomas, missense point mutations were detected in seven of them at codon A248C, 28 of them at codon S249C, and three of them at codon T375C, similar to data from previous reports. When the results of the FGFR3 thanatophoric dysplasia mutations located in exon 7, A248C and S249C and in exon 10, G372C and T375C, were analyzed one by one or as a group, despite the findings of previous research reports, our data suggest that these mutations are detected homogenously regardless of the tumor classification and tumor grade. © FUNPEC-RP

    Re-irradiation with stereotactic radiotherapy for recurrent high grade glial tumors

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    Background: Despite the radical treatments applied, recurrence is encountered in the majority of high-grade gliomas (HGG). There is no standard treatment when recurrence is detected, but stereotactic radiotherapy (SRT) is a preferable alternative. The aim of this retrospective study is to evaluate the efficacy of SRT for recurrent HGG, and to investigate the factors that affect survival. Materials and methods: From 2013 to 2021, a total of 59 patients with 64 lesions were re-irradiated in a single center with the CyberKnife Robotic Radiosurgery System. The primary endpoints of the study were overall survival (OS), progression free survival (PFS) and local control rates (LCR). Results: The median time to first recurrence was 13 (4–85) months. SRT was performed as a median prescription dose of 30 Gy (range 15–30), with a median of 5 fractions (1–5). The median follow-up time was 4 months (range 1–57). The median OS was 8 (95% CI: 4.66-11.33) months. Age, grade 3, tumor size were associated with better survival. The median PFS was 5 [95% confidence interval (CI): 3.39–6.60] months. Age, grade 3 and time to recurrence &gt; 9 months were associated with improved PFS. Grade 3 gliomas (p = 0.027), size of tumor &lt; 2 cm (p = 0.008) remained independent prognostic factors for OS in multivariate analysis. Conclusion: SRT is a viable treatment modality with significant survival contribution. Since it may have a favorable prognostic effect on survival in patients with tumor size &lt; 2 cm, we recommend early diagnosis of recurrence and a decision to re-irradiate a smaller tumor during follow-up.

    Ruthenium(II) Complex Based Photodiode for Organic Electronic Applications

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    In this study, the electrical and photoresponse properties of a photovoltaic device with Ruthenium(II) complex interfacial thin film were investigated. Heteroleptic Ru(II) complex including bidentate and tridentate ligands thin film was coated on n-Si substrate by the spin coating technique. From current-voltage (I-V) measurements of an Au/Ru(II)/n-Si photodiode, it is observed that the reverse bias current under light is higher than that of the current in the dark. This indicates that the photodiode exhibits a photoconducting characteristic. The transient measurements such as photocurrent, photocapacitance and photoconductance were performed under various illumination conditions. These measurements indicate that the photodiode has a high photoresponsivity. The electrical parameters such as barrier height (I broken vertical bar(b)), ideality factor (n) and series resistance (R (s)) of the photodiode were determined from the analysis of I-V characteristics. Moreover, the capacitance/conductance-voltage characteristics of the photodiode highly depend on both voltage and frequency. Results show that the heterojunction can be used for various optoelectronic applications.King Khalid University under the (Research Center for Advanced Materials Science) at King Khalid University, Kingdom of Saudi Arabia [RCAMS/KKU/002-16]Authors would like to acknowledge the support of the King Khalid University for this research through a grant RCAMS/KKU/002-16 under the (Research Center for Advanced Materials Science) at King Khalid University, Kingdom of Saudi Arabia

    Somatic gene variation profiles in geriatric and adult malignant melanoma patients

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    IntroductionSkin cancer is a highly heterogeneous disease affecting substantial geriatric individuals. Therefore, understanding gene variants and their presence in geriatric and adult skin cancer patient groups is valuable for the improvement of healthcare policies. The somatic variation profile in geriatric patients diagnosed with malignant melanoma (MM) was examined retrospectively by comparing them to the younger cases to reveal the clinical importance of the panel tests.MethodsThe study included all adult MM patients referred to Molecular Pathology Laboratory from Oncology Clinic between 2019 and 2023. The patients (n = 103) were chronologically divided into geriatric (≥65) and adult (&lt;65 years) groups. The results of targeted next generation sequencing panel studied with probe-capture method were evaluated retrospectively.ResultsAmong the study cohort, 58 (56.31%) were male, 45 (43.69%) were female, and also 55 were in the geriatric age group, 48 were in the adult group with an overall mean age of 63.30 years. The most commonly encountered pathogenic variants in the geriatric MM group were BRAF V600E (14.55%) and V600K (7.27%) variants in Exon 15 followed by NRAS (9.09%), NF1 (9.09%), KIT (5.45%), KRAS (5.45%), CDKN2A (3.64%), and PTEN (3.63%). In the adult MM group, the most common pathogenic variants were BRAF V600E (39.58%) and V600K (8.33%) followed by NRAS (14.58%), NF1 (8.33%), PTEN (8.33%), BRCA2 (8.33%), and TP53 (4.17%).ConclusionsDelineating the distribution of somatic variations in geriatric MM cases holds significant importance in the development of healthcare policies. These data are the first reported findings from Türkiye
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