1,003 research outputs found
Distinct ultraviolet-signaling pathways in bean leaves. DNA damage is associated with Ă-1,3-glucanase gene induction, but not with flavonoid formation
The enzyme beta-1,3-glucanase (betaGlu) was found to be strongly induced by ultraviolet (UV-B; 280-320 nm) radiation in primary leaves of French bean (Phaseolus vulgaris). This was demonstrated on the level of gene transcription, protein synthesis, and enzyme activity and was due to the expression of bean class I betaGlu (pGlu I). In contrast to other proteins of the family of pathogenesis-related proteins, the induction of betaGlu I by UV correlated with the formation of photoreversible DNA damage, i.e. Pyrimidine dimer formation. In conditions that allowed photorepair of this damage, betaGlu I induction was blocked. Therefore, UV-induced DNA damage seems to constitute a primary signal in the pathway leading to the induction of the betaGlu I gene(s). The induction was a local response because in partly irradiated leaves betaGlu I was selectively found in leaf parts exposed to UV. Although short wavelength UV (lambda 295 nm) as present in natural radiation was still effective. In contrast to UV induction of betaGlu I, the induction of flavonoids in bean leaves was optimally triggered by much more moderate fluences from the UV wavelength range no longer effective in betaGlu I induction. UV induction of the flavonoid pathway shows no correlation with DNA damage and thus should be mediated via a different signal transduction pathway
Lung cancer in lifetime nonsmoking men â results of a case-control study in Germany
Epidemiological studies of lung cancer among nonsmoking men are few. This caseâcontrol study was conducted among lifetime nonsmoking men between 1990 and 1996 in Germany to examine lung cancer risk in relation to occupation, environmental tobacco smoke, residential radon, family history of cancer and previous lung disease. A total of 58 male cases with confirmed primary lung cancer and 803 male population controls who had never smoked more than 400 cigarettes in their lifetime were personally interviewed by a standardized questionnaire. In addition, 1-year radon measurements in the living and bedroom of the subjects' last dwelling were carried out. Unconditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI). Having ever worked in a job with known lung carcinogens was associated with a two-fold significantly increased lung cancer risk (OR = 2.2; Cl = 1.0â5.0), adjusted for age and region. The linear trend test for lung-cancer risk associated with radon exposure was close to statistical significance, demonstrating an excess relative risk for an increase in exposure of 100 Bq mâ3 of 0.43 (P = 0.052). Nonsignificantly elevated effects of exposure to environmental tobacco smoke in public transportation and in social settings were observed. No associations with a family history of cancer or previous lung diseases were found. Our results indicate that occupational carcinogens and indoor radon may play a role in some lung cancers in nonsmoking men. © 2001 Cancer Research Campaign http://www.bjcancer.co
Interpretable Anomaly Detection in Echocardiograms with Dynamic Variational Trajectory Models
We propose a novel anomaly detection method for echocardiogram videos. The
introduced method takes advantage of the periodic nature of the heart cycle to
learn three variants of a variational latent trajectory model (TVAE). While the
first two variants (TVAE-C and TVAE-R) model strict periodic movements of the
heart, the third (TVAE-S) is more general and allows shifts in the spatial
representation throughout the video. All models are trained on the healthy
samples of a novel in-house dataset of infant echocardiogram videos consisting
of multiple chamber views to learn a normative prior of the healthy population.
During inference, maximum a posteriori (MAP) based anomaly detection is
performed to detect out-of-distribution samples in our dataset. The proposed
method reliably identifies severe congenital heart defects, such as Ebstein's
Anomaly or Shone-complex. Moreover, it achieves superior performance over
MAP-based anomaly detection with standard variational autoencoders when
detecting pulmonary hypertension and right ventricular dilation. Finally, we
demonstrate that the proposed method enables interpretable explanations of its
output through heatmaps highlighting the regions corresponding to anomalous
heart structures.Comment: accepted at IMLH workshop ICML 202
Constraining stochastic 3-D structural geological models with topology information using Approximate Bayesian Computation in GemPy 2.1
Acknowledgements. We would like to thank Total E&P UK in Aberdeen for funding this research. We also thank Fabian Stamm for providing the wonderful synthetic geomodel used in this paper. We are grateful for the constructive reviews from Ashton Krajnovich and an anonymous reviewer for helping us improve this manuscript.Peer reviewedPublisher PD
Efficacy and safety of peginterferon alfa-2a + RBV in cHCV/HIV- vs cHCV-infected patients: interim analysis of a multicenter German cohort
Absolute-Magnitude Distributions and Light Curves of Stripped-Envelope Supernovae
The absolute visual magnitudes of three Type IIb, 11 Type Ib and 13 Type Ic
supernovae (collectively known as stripped-envelope supernovae) are studied by
collecting data on the apparent magnitude, distance, and interstellar
extinction of each event. Weighted and unweighted mean absolute magnitudes of
the combined sample as well as various subsets of the sample are reported. The
limited sample size and the considerable uncertainties, especially those
associated with extinction in the host galaxies, prevent firm conclusions
regarding differences between the absolute magnitudes of supernovae of Type Ib
and Ic, and regarding the existence of separate groups of overluminous and
normal-luminosity stripped-envelope supernovae. The spectroscopic
characteristics of the events of the sample are considered. Three of the four
overluminous events are known to have had unusual spectra. Most but not all of
the normal luminosity events had typical spectra. Light curves of
stripped-envelope supernovae are collected and compared. Because SN 1994I in
M51 was very well observed it often is regarded as the prototypical Type Ic
supernova, but it has the fastest light curve in the sample. Light curves are
modeled by means of a simple analytical technique that, combined with a
constraint on E/M from spectroscopy, yields internally consistent values of
ejected mass, kinetic energy, and nickel mass.Comment: 39 pages, 14 figures, 7 tables; Accepted to A
Classification of Inflammatory Bowel Disease from FormalinâFixed, ParaffinâEmbedded Tissue Biopsies via Imaging Mass Spectrometry
Purpose:
Discrimination between ulcerative colitis (UC) and Crohn's disease (CD) by histologic features alone can be challenging and often leads to inaccurate initial diagnoses in inflammatory bowel disease (IBD) patients. This is mostly due to an overlap of clinical and histologic features. However, exact diagnosis is not only important for patient treatment but it also has a socioeconomic impact. It is therefore important to develop and improve diagnostic tools complementing traditional histomorphological approaches.
Experimental Design:
In this retrospective proof-of-concept study, the utilization of MALDI imaging is explored in combination with multi-variate data analysis methods to classify formalin-fixed, paraffin-embedded (FFPE) colon biopsies from UC (87 biopsies, 14 patients), CD (71 biopsies, 14 patients), and normal colonic (21 biopsies, 14 patients) tissues.
Results:
The proposed method results in an overall balanced accuracy of 85.7% on patient and of 80.4% on sample level, thus demonstrating that the assessment of IBD from FFPE tissue specimens via MALDI imaging is feasible.
Conclusions and Clinical Relevance:
The results emphasize the high potential of this method to distinguish IBD subtypes in FFPE tissue sections, which is a prerequisite for further investigations in retrospective multicenter studies, as well as for a future implementation into clinical routine
Enhancement of PCA-based fault detection system through utilising dissimilarity matrix for continuous-based process
This research is about enhancement of PCA-based fault detection system through utilizing dissimilarity matrix. Nowadays, the chemical process industry is highly based on the non-linear relationships between measured variables. However, the conventional PCA-based MSPC is no longer effective because it only valid for the linear relationships between measured variables. Due in order to solve this problem, the technique of dissimilarity matrix is used in multivariate statistical process control as alternative technique which models the non-linear process and can improve the process monitoring performance. The conventional PCA system was run and the dissimilarity system was developed and lastly the monitoring performance in each technique were compared and analysed to achieve aims of this research. This research is to be done by using Matlab software. The findings of this study are illustrated in the form of Hotellingâs T2 and Squared Prediction Errors (SPE) monitoring statistics to be analysed. As a conclusion, the dissimilarity system is comparable to the conventional method. Thus can be the other alternative ways in the process monitoring performance. Finally, it is recommended to use data from other chemical processing systems for more concrete justification of the new technique
The Effects of Perinatal Oxycodone Exposure on Behavioral Outcome in a Rodent Model
Opiate addiction is now a major public health problem. Perinatal insults and exposure to opiates such as morphine in utero are well known to affect development of the hypothalamicâpituitaryâadrenal axis of the offspring adversely and are associated with a higher risk of developing neurobehavioral problems. Oxycodone is now one of the most frequently abused pain killers during pregnancy; however, limited data are available regarding whether and how perinatal oxycodone exposure (POE) alters neurobehavioral outcomes of the offspring. We demonstrated that exposure to 0.5 mg/kg/day oxycodone in utero was associated with hyperactivity in adult rats in an open field. No significant effects of POE were detected on isolation-induced ultrasonic vocalizations in the early postnatal period or on learning and memory in the water maze in adult offspring. Our findings are consistent with hyperactivity problems identified in children exposed to opiates in utero
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