•We present an analytical model for the air damping of laterally oscillating MEMS/MOEMS.•It agrees well with both measurement and numerical simulations.•We also show how holes in the laterally moving ...plate affect the quality facor of the device.
We report on an analytical model for the air damping of laterally oscillating MEMS and MOEMS following up on our recent paper 1. It can be used to more efficiently design micromechanical devices with tailor-made Q-factors for specific applications. The surface force responsible for the air damping was divided into contributions which were investigated separately. These include squeeze-film damping and the viscous forces responsible for shear wave emission and Couette type flow. Since the squeezing part is mostly underestimated in the current models, we applied more appropriate boundary conditions during the solution of Reynold's lubrication equation. The viscous contributions were investigated with respect to how holes – due to fabrication process or readout – in the moving plate affect the damping. We tested this model against FVM computations (OpenFOAM) and measurements of MOEMS test devices. It was in good agreement with both.
Dysfunctional attitudes are a feature of depression that has been correlated with receptor binding abnormalities in limbic and cortical regions. We sought to investigate the functional neuroanatomy ...of dysfunctional attitudes in major depressive disorder (MDD) and the effects of treatment with cognitive-behavioural therapy (CBT).
Participants were 16 patients with unipolar depression in an acute depressive episode (mean age 40.0 years) and 16 matched healthy controls (mean age 39.9 years). Patients were medication free and received a course of treatment with CBT. All participants underwent functional magnetic resonance imaging (fMRI) scans at baseline and at week 16, prior to the initiation of therapy and following the course of CBT for patients. During each fMRI scan, participants indicated their attributions to statements from a modified Dysfunctional Attitudes Scale (mDAS-48).
MDD patients in an acute depressive episode endorsed a greater number of extreme responses to DAS statements, which normalized following CBT treatment. Extreme attributions were associated with greater activation in the left hippocampal region, inferior parietal lobe and precuneus in MDD patients as compared with healthy controls as a main effect of group. An interaction effect was found in the left parahippocampal region, which showed less attenuation in MDD patients at the follow-up scan relative to healthy controls.
Attenuation of activity in the parahippocampal region may be indicative of an improvement in dysfunctional thinking following CBT treatment in depression, while persistent engagement of regions involved in attentional processing and memory retrieval with extreme attributions reflects a trait feature of depression.
Multi-label classification is a type of supervised learning where an instance may belong to multiple labels simultaneously. Predicting each label independently has been criticized for not exploiting ...any correlation between labels. In this article we propose a novel approach, Nearest Labelset using Double Distances (
), that predicts the labelset observed in the training data that minimizes a weighted sum of the distances in both the feature space and the label space to the new instance. The weights specify the relative tradeoff between the two distances. The weights are estimated from a binomial regression of the number of misclassified labels as a function of the two distances. Model parameters are estimated by maximum likelihood.
only considers labelsets observed in the training data, thus implicitly taking into account label dependencies. Experiments on benchmark multi-label data sets show that the proposed method on average outperforms other well-known approaches in terms of 0/1
, and
and ranks second on the
(after a method called ECC) and on
(after a method called
).
Thin flexible sheets of high-permeability FINEMET® foils encased in thin plastic layers have been used to shield various types of 20-cm-diameter photomultiplier tubes from ambient magnetic fields. In ...the presence of the Earth's magnetic field this type of shielding is shown to increase the collection efficiency of photoelectrons and can improve the uniformity of response of these photomultiplier tubes.
Alternative splicing of the oncogene murine double minute 2 (MDM2) is induced in response to genotoxic stress. MDM2-ALT1, the major splice variant generated, is known to activate the p53 pathway and ...impede full-length MDM2's negative regulation of p53. Despite this perceptible tumor-suppressive role, MDM2-ALT1 is also associated with several cancers. Furthermore, expression of MDM2-ALT1 has been observed in aggressive metastatic disease in pediatric rhabdomyosarcoma (RMS), irrespective of histological subtype. Therefore, we generated a transgenic MDM2-ALT1 mouse model that would allow us to investigate the effects of this splice variant on the progression of tumorigenesis. Here we show that when MDM2-ALT1 is ubiquitously expressed in p53 null mice it leads to increased incidence of spindle cell sarcomas, including RMS. Our data provide evidence that constitutive MDM2-ALT1 expression is itself an oncogenic lesion that aggravates the tumorigenesis induced by p53 loss. On the contrary, when MDM2-ALT1 is expressed solely in B-cells in the presence of homozygous wild-type p53 it leads to significantly increased lymphomagenesis (56%) when compared with control mice (27%). However, this phenotype is observable only at later stages in life (⩾18 months). Moreover, flow cytometric analyses for B-cell markers revealed an MDM2-ALT1-associated decrease in the B-cell population of the spleens of these animals. Our data suggest that the B-cell loss is p53 dependent and is a response mounted to persistent MDM2-ALT1 expression in a wild-type p53 background. Overall, our findings highlight the importance of an MDM2 splice variant as a critical modifier of both p53-dependent and -independent tumorigenesis, underscoring the complexity of MDM2 posttranscriptional regulation in cancer. Furthermore, MDM2-ALT1-expressing p53 null mice represent a novel mouse model of fusion-negative RMS.
A simple parametric model has been developed for the simulation of boron carbide oxidation tests at high temperatures done at Forschungszentrum Karlsruhe. The model predicts that an equilibrium oxide ...film thickness is reached, whose value is only determined by the two rate parameters of the model. Applying the principles of convective mass transfer in coolant channels, one is able to establish the link from the parametric model to a more generalized consideration, which allows to identify the hydrogen surface concentration as a parameter, which is independent of the flow conditions.
•ZnTe nanowires are grown by molecular beam epitaxy using vapor-liquid-solid process.•Growth evolution of ZnTe nanowires on (001) GaAs substrates is examined.•The nanowire growth starts in-plane by ...switches to out-of-plane when they intersect.
The growth evolution of gold-catalyzed ZnTe nanowire condensates on (001) GaAs substrates is studied. The samples are obtained by molecular beam epitaxy. The growth of nanowires has been monitored in situ by RHEED and investigated ex-situ by TEM, SEM, XRD. In addition to nanowires sticking out of surface in 〈111〉 direction, formation ZnTe thin film is observed. It is found, that formation of the nanowire condensate occurs in three stages. At the initial stage of growth planar nanowires form and continue to grow in 〈110〉 direction until their intersection occurs. After the intersection, nanowires change the growth direction from planar to out-of-plane. At the final stage of growth in-plane nanowires coalescence forming a thin film. In addition to main reflections from ZnTe nanowires some oriented spots and rings have been observed on RHEED patterns. We attribute these spots to twin formation in nanowires and rings to a presence of disoriented domains in ZnTe film condensates.
Purpose: The insulin-like growth factor (IGF) signaling system is involved in breast cancer initiation and progression. The prognostic
relevance of tumor expression patterns of IGFI-related proteins ...remains poorly understood. This study associates the expression
of selected IGF proteins with breast tumor and patient characteristics.
Experimental Design: IGFI, IGFI receptor, IGF-binding protein (IGFBP)2, and IGFBP3 expression was measured in 855 primary breast carcinomas by
immunohistochemistry using tissue microarrays. We investigated the association of tumor and nodal stage, grade, hormone receptor
status, HER2 gene amplification, menopausal status, body mass index, and survival with IGF protein expression.
Results: In contrast to IGFI, the expression of IGFI receptor, IGFBP2, and IGFBP3 was associated with estrogen receptor status. In
addition, IGFBP3 was positively correlated with body mass index and premenopausal status. Importantly, IGFBP2 was an independent
and positive predictor of overall survival (hazard ratio, 0.48; 95% confidence interval, 0.24-0.95; P = 0.04). There was a weak suggestion for IGFBP2 and overweight to modify each other's effect on survival.
Conclusions: According to these results, which need confirmation in larger patient series, the prognostic relevance of IGFBP2 and IGFBP3
protein expressions in breast cancer may depend on the hormonal context and body weight. Clin Cancer Res; 16(3); 1025–32
•A MOEMS transducer with a non-linear transfer characteristic is presented.•The MOEMS is based on the modulation of a light flux that passes through a pair of micro apertures.•The non-linear ...characteristic is exploited for the quantification of static displacements.•The presented approach can be used to increase the resolutions compared to simple DC measurements.
This contribution describes an micro-opto-electro-mechanical system transducer with a well defined inherent non-linear transfer behavior and its impact on the quantification of static and dynamic displacements in a vibrating measurement mode. The transducer’s output signal is proportional to a light-flux that is modulated by two overlapping aperture arrays. One of these arrays is deposited on a fixed glass cover while the other one is etched into a moveable seismic mass of a silicon micro-electro-mechanical chip. The non-linear transfer characteristic is achieved by pairing triangularly shaped apertures with rectangular ones. The seismic mass is actuated by a mechanical shaker unit and the resulting first and second harmonics of the output signal are recorded with lock-in amplifiers. These harmonics contain information about both the static displacement and the vibration amplitude of the seismic mass. The presented method was tested with a proof-of-concept device and first measurement results exhibit a static displacement resolution of 3.67nm which is a slight improvement compared to DC measurement approaches exhibiting a resolution of 5.39nm. Furthermore, a inclination sensor was built employing this vibrating measurement approach showing that the resolution was improved at least by an factor of three.
Reduced activation ferritic-martensitic steels are considered for application in future fusion technology as structural materials. In the past, corrosion testing was performed at moderate ...temperatures of about 480
°C and showed acceptable homogeneous corrosion behavior. However, in the mean time the envisaged temperature limits increased to around 550
°C. Due to large uncertainties in extrapolations of the corrosion behavior from 480 to 550
°C, long-term tests were initiated which include also the development of modeling tools and analyzing for the first time in more detail transport and precipitation phenomenas. The tests performed at 550
°C and flow rate of 0.22
m/s revealed a corrosion rate of about 400
μm/year with emphasis to the long term exposed samples. The high amount of dissolved components formed precipitations at cooler loop positions which led to line blockages after short operation of about 3000
h. A comparison with global Pb–17Li data and 480
°C testing will be shown.
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