gebhart/patrepeval huggingface dataset:
Potential Applications of the Ceramic Thrust Chamber Technology for Future Rocket Propulsion (2011)

The long-term development of ceramic rocket engine thrust chambers at the German Aerospace Center (DLR) currently leads to designs of\nself-sustaining, transpiration-cooled, fibre-reinforced ceramic rocket engine chamber structures. This paper discusses characteristic issues and\npotential benefits introduced by this technology. Achievable benefits are the reduction of weight and manufacturing cost, as well as an increased\nreliability and higher lifetime due to thermal cycle stability.\nExperiments with porous Ceramic Matrix Composite (CMC) material for rocket engine chamber walls are conducted at the DLR since the end of\nthe 1990ies. This paper discusses the current status of DLR’s ceramic thrust chamber technology and potential applications for high performance\nengines. Parametric variations of engine sizing (such as chamber pressure and diameter) are performed. This paper furthermore describes applications\nof similar materials- and design-concepts to radiation cooled thrust chambers. The wall heat flux is analysed for different materials.
Thermoluminescence of Fourteen Alkali Halide Crystals (1957)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThermoluminescence of Fourteen Alkali Halide CrystalsLouis F. Heckelsberg and Farrington DanielsCite this: J. Phys. Chem. 1957, 61, 4, 414–418Publication Date (Print):April 1, 1957Publication History Published online1 May 2002Published inissue 1 April 1957https://pubs.acs.org/doi/10.1021/j150550a008https://doi.org/10.1021/j150550a008research-articleACS PublicationsRequest reuse permissionsArticle Views75Altmetric-Citations17LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts
Kinetics and rate constants for the reaction of tri‐n‐butylgermanium hydride with methyl iodide and carbon tetrachloride. The combination of methyl and trichloromethyl radicals in solution. (1969)

Abstract The kinetics of the photoinitiated reductions of methyl iodide and carbon tetrachloride by tri‐n‐butylgermanium hydride in cyclohexane at 25°C have been studied and absolute rate constants have been measured. Rate constants for the combination of CH 3 ċ and CCl 3 ċ radicals are equal within experimental error and are also equal to the values found for the self‐reactions of most non‐polymeric radicals in low viscosity solvents, i.e. ∼1–3 × 10 9 M −1 sec −1 . Rate constants for hydrogen atom abstraction by CH 3 ċ and CCl 3 ċ radicals are both ∼1−2 × 10 5 M −1 sec −1 . Tri‐n‐butyltin hydride is about 10–20 times as good a hydrogen donor to alkyl radicals as is tri‐n‐butylgermanium hydride. The strength of the germanium–hydrogen bond, D (n‐Bu 3 Ge–H) is estimated to be approximately 84 kcal/mole.
A contribution on the Hector, California bentonite deposit (1958)

The unique Hector bentonite occurs along a northwest-trending fault zone for a distance of about five miles. Hot springs emanating along this fault during Pliocene (?) time deposited travertine in a then existing lake in which sand, marl and silicic pyroclastics also were being deposited. The tuff lying on the travertine benches was altered to saponite by solutions containing lithium and fluorine in the last stages of hot spring activity, with the magnesium being extracted from the lake water. Analcime, representing alteration of the tuff when the springs were inactive, is found below and above the bentonite bed. Clinoptilolite is present directly associated with the hot spring activity.The amount of travertine decreases to the northwest as do the contents of lithium, fluorine, and magnesium in the clay, which approaches an aluminum montmorillonite in composition. In a restricted basin where magnesium is available, acid solutions from hot springs apparently produce a chemical system that forms a trioctahedral bentonite preferentially to a dioctahedral variety even though the parent material approximates the chemical composition of an aluminum montmorillonite.Minor faulting and slumping have produced gouge zones and small downward displacements of the irregular bentonite lenses on the southwest side of the main fault. The deposit is located in a valley of low relief; the dominant structural feature is the high, developed by the deposition of sediments and pyroclastics on the travertine benches. River gravels and muds, and a basalt flow in places, unconformably overlie the series.
PIN diode and integrated JFET on high resistivity silicon: a new test structure (2005)

A new test structure intended as a pixel for segmented X- and /spl gamma/-ray detectors has been designed fabricated and tested. The structure consists of a PIN diode of 0.8 mm/sup 2/ area and of an n-channel JFET integrated on the same high resistivity (6 k/spl Omega/ cm) silicon chip. The electrical parameters-leakage current, the transconductance and the capacitance have good expected values. Instead, noise in excess is present in the transistor. Operated at room temperature as an X-ray detector with the integrated frontend transistor in the charge sensitive configuration, the new test structure shows an equivalent noise charge of about 60 electrons rms at the optimum shaping time of 3-6 /spl mu/s.
Breast cancer vaccines: maximizing peptide-based vaccines by regulatory T cell depletion and toll-like receptor 9 activation (2007)

Background Breast cancer is the most prevalent cancer in the world due to high incidence and favorable prognoses. Relapse is the major cause of mortality and will occur in up to 65% of patients with node-positive disease. Thus, effective longterm protection strategies are needed for preventing relapse. One approach that has generated interest in recent years is cancer vaccines. One of the problems with the translation of cancer vaccines is that multiple boosters are required in order to generate high-avidity memory immunity that is able to recognize naturally processed antigens. Our goal in this study was to determine if the need for boosters could be eliminated by preconditioning the immune system with anti-CD25 antibodies, which is known to deplete regulatory T cells, the latter of which are known to regulate the development of high-avidity memory T cells.
Expression of p53 in oligodendrogliomas (1993)

The expression of the nuclear protein p53 in oligodendrogliomas was investigated by immunohistochemistry, using a monoclonal anti-p53 antibody (DO-7) on formalin-fixed, paraffin-embedded material in 84 histologically verified cases, and compared with the histopathological grade and survival. p53-immunoreactive cells were found in 75 per cent of the samples acquired at the first biopsy. The p53 labelling index was not related to the degree of nuclear anaplasia. Tumour cases with more than 75 per cent p53 immunostained cells had a rapidly fatal clinical course. However, no significant correlation was found between p53 labelling index and tumour grade, mitotic index, or ploidy status. In most tumour recurrences (n = 25), the p53 labelling index increased or remained at the level of the first biopsy. In five cases (6 per cent), p53 was absent in the first sample as well as in the recurrence. Irrespective of the underlying aberration of either the gene or the metabolic pathway of p53, it is concluded that a high percentage (i.e., more than 75 per cent) of p53-immunolabelled cells is predictive of an unfavourable clinical course, while a percentage lower than 75 per cent immunoreactive cells does not exclude a rapid fatal outcome.
Loop Disorders: Insights Derived from Defined Genotypes (2010)

Great progress has been made in the last 15 years in the characterization and the pathophysiological understanding of renal salt and water wasting associated with inherited disorders of the thick ascending limb (TAL) of Henle's loop, the loop disorders. Besides careful clinical observations and innovative physiological concepts, molecular genetics have made this progress possible. So far, mutations in five different genes may be responsible for the loop disorders. These gene products are as follows: NKCC2 symporter, ROMK, ClC-Ka, ClC-Kb, and barttin, a β-subunit to both chloride channels. The key symptoms, such as polyhydramnios secondary to fetal polyuria, postnatal volume depletion with hypotension, iso- or hyposthenuria, hyperprostaglandinuria and hypercalciuria followed by hypokalemic alkalosis secondary to hyperaldosteronism, are typical features of loop disorders that are restricted to TAL, such as in disorders with NKCC2 and ROMK mutations. However, transient perinatal hyperkalemia in infants with ROMK mutations suggests an additional function of ROMK for K secretion in the cortical collecting duct. The extremely rare human ClC-Kamutation has only been described in combination with ClC-Kb mutations. Similar to barttin mutations, this double knockout of transepithelial salt transport in TAL and in distal convoluted tubule (DCT) leads to a severe loop disorder with deafness. In contrast, the isolated ClC-Kb mutation predominantly appears as an incomplete loop disorder with features similar to an isolated DCT defect, because ClC-Kb function in TAL can in part be compensated by ClC-Ka. This compensation does not exist in DCT. Besides these defined genotypes, the type and the severity of mutation as well as the onset and quality of medical care are important determinants for the patients' outcome. Considering a few variables, such as transient hyperkalemia, disease onset beyond neonatal period, profound hypochloremia and hypokalemia, or congenital hearing loss, might be helpful to guide genetic testing efficiently.
Adaptation to Life in the High Andes: Nocturnal Oxyhemoglobin Saturation in Early Development (2016)

Physiological adaptation to high-altitude living in native Andeans is unlikely to compensate for the significant differences we observed between diurnal and nocturnal oxyhemoglobin saturation, most marked in infancy. This vulnerability to sleep-related hypoxia in early childhood has potential lifespan implications. Future studies should characterize the sleep- related respiratory physiology underpinning our observations.
Absolute and relative surrogate measurements of the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mmultiscripts><mml:mi mathvariant="normal">U</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>236</mml:mn></mml:mrow></mml:mmultiscripts></mml:math>(<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>n</mml:mi><mml:mo>,</mml:mo><mml:mi>f</mml:mi></mml:mrow></mml:math>) cross section as a probe of angular momentum effects (2007)

Using both the absolute and relative surrogate techniques, the $^{236}\mathrm{U}$($n,f$) cross section was deduced over an equivalent neutron energy range of 0 to 20 MeV. A 42 MeV $^{3}\mathrm{He}$ beam from the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory was used to perform a ($^{3}\mathrm{He}$,\ensuremath{\alpha}) pickup reaction on targets of $^{235}\mathrm{U}$ (${J}^{\ensuremath{\pi}}=7/{2}^{\ensuremath{-}}$) and $^{238}\mathrm{U}$ (${J}^{\ensuremath{\pi}}={0}^{+}$) and the fission decay probabilities were determined. The $^{235}\mathrm{U}$($^{3}\mathrm{He}$,$\ensuremath{\alpha}f$) and $^{238}\mathrm{U}$($^{3}\mathrm{He}$,$\ensuremath{\alpha}f$) were surrogates for $^{233}\mathrm{U}$($n,f$) and $^{236}\mathrm{U}$($n,f$), respectively. The cross sections extracted using the surrogate method were compared to directly measured cross sections. The sensitivity of these cross sections to the ${J}^{\ensuremath{\pi}}$-population distributions was explored.
Charge carrier recombination in conjugated polymers studied by field-assisted femtosecond spectroscopy (2002)

Electroluminescence in organic light-emitting diodes (OLEDs) arises from recombination of the injected positive and negative charges, to form singlet excitons, and their subsequent radiative decay [1]. The quantum efficiency η of this process was thought to have an upper limit of 25%, given by the statistics of spin multiplicity: in fact for recombination of an electron-hole pair there are four possible microstates, of which three are triplet (non emissive) states and only one is a luminescent singlet state. Recent experimental and theoretical work [2-4], however, showed that higher values of η are possible. Since η is equal to σ S /(σ S +3σ T ), where σ S(T) is the cross section of charge recombination into singlet (triplet) states, the results were explained postulating higher values for σ S with respect to σ T .
Experimental Investigation of Flow Boiling Performance of Open Microchannels With Uniform and Tapered Manifolds (OMM) (2013)

Boiling can provide orders of magnitude higher cooling performance than a traditional air cooled system especially related to electronics cooling application. It can dissipate large quantities of heat while maintaining a low surface temperature difference. Flow boiling with microchannels has shown a lot of potential due to its high surface area to volume ratio and latent heat removal. Flow instabilities and early critical heat flux have however prevented its successful implementation. A novel flow boiling design is experimentally investigated to overcome the above mentioned disadvantages while presenting a very low pressure drop. The design uses open microchannels with a tapered manifold (OMM) to provide stable and efficient operation. Distilled, degassed water at atmospheric pressure is used as the fluid medium. Effect of tapered block with varied dimension is investigated. Heat transfer coefficient and pressure drop data for uniform and tapered manifolds for plain and microchannel chips are presented. A maximum heat flux of 281.2 W/cm2 at 10.1 °C wall superheat is obtained with microchannel chips using a tapered manifold. The CHF was not reached as the performance exceeded the heater capacity. The maximum pressure drop obtained for the above mentioned configuration was only 3.3 kPa.
Apparent Motion of Subjective Surfaces (1985)

Apparent motion of an illusory surface was produced by presenting two spatially separated illusory squares in an appropriately timed sequence. Control experiments showed that the effect arose from the illusory contours themselves and not from motion of the cut sectors on the discs. When a template of this movie was superimposed on 'wallpaper' composed of a regular matrix of spots, the spots appeared to move with the illusory surface even though they were physically stationary. This effect ('motion capture') suggests that the motion of certain salient features in the visual field gets spontaneously attributed to even static elements in the vicinity.
Human alpha 1(III) and alpha 2(V) procollagen genes are located on the long arm of chromosome 2. (1985)

The multigene procollagen family encodes probably greater than 20 genetically distinct but structurally related polypeptide chains. Recent characterization of human procollagen clones has allowed determination of functional domains within the proteins, genomic organization, and chromosomal location. Previously, we assigned the coordinately expressed type I genes (alpha 1 and alpha 2) to chromosomes 17 and 7, respectively, and now other investigators have mapped the type II gene to chromosome 12 [Strom, C. M., Eddy, R. L. & Shows, T. B. (1984) Somatic Cell Genet. 10, 651-655]. Recently, we isolated cDNA clones encoding the fourth interstitial procollagen, type III, and the alpha 2 chain of the type V cytoskeletal components. To determine whether these genes were clustered with alpha 1(I), alpha 2(I), or alpha 1(II) or were further dispersed in the genome, in situ hybridization of the alpha 1(III) and alpha 2(V) probes to metaphase chromosomes was carried out. Here we report a fourth autosome with procollagen gene loci but the first cytological evidence for linkage. By using normal and translocated cell lines, our results show that both the alpha 1(III) and alpha 2(V) procollagen genes map to the q24.3----q31 region of chromosome 2.
Analysis of UDP Traffic Usage on Internet Backbone Links (2009)

We compared UDP and TCP traffic in several traffic traces collected from different networks and geographical locations, at different times. We find that TCP still dominates in terms of packets and bytes, but UDP is now often responsible for the largest fraction of flows on a given link. A port-based analysis suggests that the recent increase in UDP flows on the traces analyzed stems mainly from P2P applications using UDP for their overlay signaling traffic. This trend may again change with the advent of IPTV and UDP based P2P applications, which not only signal, but also transport large data segments via UDP. We will continue to monitor available data to track trends in UDP usage, and specifically seek data from China where UDP-based IPTV traffic is already common. Finally, we note that precise traffic classification requires methods beyond simple port classification. Most current traffic classification techniques focus on TCP, with only preliminary examination of techniques for UDP traffic (other than deep packet inspection). Given the growing evidence for the use of UDP for increasingly popular applications, including for bulk data transfer in China, we conclude that traffic analysis methods must evolve to classify also UDP traffic.
Genetic Polymorphisms in the Fourth Component of Complement (C4) and in Properdin Factor B (BF) in Japanese Patients with Palmoplantar Pustulosis (1992)

Genetic polymorphisms in the fourth component of complement (C4) and in properdin factor B (BF) were investigated in 49 and 32 Japanese patients with palmoplantar pustulosis (PPP), respectively. C4B2 was significantly increased in frequency, whereas no significant deviations were detected in BF compared with the controls. These results may indicate that complement polymorphisms are involved in the pathogenesis of PPP.
Fast wide-angle BPMs using complex Jacobi iteration (2009)

Efforts to improve the limitations of the paraxial approximation in the beam propagation method have so far made use of wide-angle formulations. Different treatments of WA-BPM based on the slowly varying envelope approximation (SVEA) have been developed. There exist real Pade approximant operators mentioned here as Hadley(m,n) [1] and complex Pade approximant operators [2]. In addition, treatments of WA-BPM without having to make the SVEAs have also been reported, including the series expansion technique of the propagator, the split-step of beam propagation equation and the rational KP(m,n) approximant we recently proposed [3]. For Hadley(1,1) and KP(1,1) approximant-based beam propagation of wave profiles within a 2D cross section, the beam propagation equation can be cast in terms of a Helmholtz equation with source term, but that equation needs to be solved efficiently since numerous propagation steps are routinely required during the course of a problem solution. For this purpose a recently introduced complex Jacobi iterative (CJI) method [4] is proposed for the solution of WA beam propagation and shown to be highly efficient. Since the utility of the CJI technique depends mostly upon its execution speed in comparison with the traditional direct matrix inversion (DMI) method, we also present several speed comparisons. Numerical implementations are carried out for 3D optical waveguide structures.
Anxious and depressive symptoms in Parkinson's disease: The French cross‐sectionnal DoPaMiP study (2009)

Anxiety has been less extensively studied than depression in Parkinson's disease (PD). The DoPaMiP survey allowed assessing simultaneously anxiety and depressive symptoms in PD and comparing correlations of both symptoms with clinical and therapeutic features of the disease. Cross sectional survey conducted prospectively in 450 ambulatory nondemented PD patients and 98 patients with other disorders than PD. Anxiety and depressive symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS), parkinsonism using the Unified Parkinson's Disease Rating Scale (UPDRS). Other clinical factors were measured using a structured standardized examination/questionnaire. The mean HADS-A (anxiety) subscore was higher in PD patients than in the others (8.2 +/- 3.9 vs. 6.5 +/- 3.2, P < 10(-4)) as was the HADS-D (depressive) subscore (6.6 +/- 3.8 vs. 3.9 +/- 3.2, P < 10(-4)). Patients with possible/probable anxious signs (HADS-A >or= 8) were more prevalent in PD (51% vs. 29%, P < 10(-4)) as were those with depressive symptoms (40% vs. 10%, P < 10(-4)). Conversely, anxiolytic and antidepressant medications consumption was not different between the 2 groups. Patients with anxious symptoms were more frequently female and younger than those without such symptoms, while those with depressive symptoms had more severe indices of parkinsonism, more comorbidities and lower cognitive function (Mini Mental State Exam). The logistic regression model revealed that patients with depressive symptoms received more frequently levodopa and less frequently a dopamine agonist. Anxiety and depressive symptoms were more frequent in PD patients than in medical control group. Both symptoms were commonly associated in the same PD patients, but were correlated with different clinical/therapeutic features, suggesting different underlying pathophysiological mechanisms.
Microwave anisotropy and dichroism of ferroelectric crystals CH3NH3HgCl3 (1985)

Microwave dielectric anisotropy of oriented crystals of CH3NH3HgCl3 is measured by a resonant cavity method at 9.5 GHz. A general expression for the perturbation cavity is given, taking into account anisotropies of the electrical properties and of the depolarisation factor of the sample. Measurements of the frequency shift and transmitted power are made versus crystal orientation relative to the microwave field. Using the general formulas established in this work, the complex permittivity tensor is calculated (at 9.5 GHz and 300 K): εc = 22.0 – j 2.60, εa = 22.0 – j 0.40 (a ⊥ c). Nous avons mesuré l'anisotropie diélectrique micro-onde de cristaux de CH3NH3HgCl3 à 9,5 GHz par une méthode en cavité. Nous avons établi une formule de perturbation générate tenant compte des anisotropies diélectriques et du coefficient de dépolarisation de l'échantillon. La mesure du glissement de fréquence et de la puissance transmise par la cavité à la résonance, nous a permis en appliquant les formules précédemment établies de calculer les termes du tenseur de permittivité du cristal (à 9,5 GHz et 300 K): εc = 22.0 – j 2.60, εa = 22.0 – j 0.40 (a ⊥ c).