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1.
Diagnostics (Basel) ; 13(18)2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37761381

ABSTRACT

In the context of liver surgery, predicting postoperative liver dysfunction is essential. This study explored the potential of preoperative liver function assessment by MRI for predicting postoperative liver dysfunction and compared these results with the established indocyanine green (ICG) clearance test. This prospective study included patients undergoing liver resection with preoperative MRI planning. Liver function was quantified using T1 relaxometry and correlated with established liver function scores. The analysis revealed an improved model for predicting postoperative liver dysfunction, exhibiting an accuracy (ACC) of 0.79, surpassing the 0.70 of the preoperative ICG test, alongside a higher area under the curve (0.75). Notably, the proposed model also successfully predicted all cases of liver failure and showed potential in predicting liver synthesis dysfunction (ACC 0.78). This model showed promise in patient survival rates with a Hazard ratio of 0.87, underscoring its potential as a valuable tool for preoperative evaluation. The findings imply that MRI-based assessment of liver function can provide significant benefits in the early identification and management of patients at risk for postoperative liver dysfunction.

2.
Sci Rep ; 13(1): 4618, 2023 Mar 21.
Article in English | MEDLINE | ID: mdl-36944670

ABSTRACT

The description of physical processes with many-particle systems is a key approach to the modeling of numerous physical systems. For example in storage rings, where ultrarelativistic particles are agglomerated in dense bunches, the modeling and measurement of their phase-space distribution is of paramount importance: at any time the phase-space distribution not only determines the complete space-time evolution but also provides fundamental performance characteristics for storage ring operation. Here, we demonstrate a non-destructive tomographic imaging technique for the 2D longitudinal phase-space distribution of ultrarelativistic electron bunches. For this purpose, we utilize a unique setup, which streams turn-by-turn near-field measurements of bunch profiles at MHz repetition rates. To demonstrate the feasibility of our method, we induce a non-equilibrium state and show that the phase-space distribution microstructuring as well as the phase-space distribution dynamics can be observed in great detail. Our approach offers a pathway to control ultrashort bunches and supports, as one example, the development of compact accelerators with low energy footprints.

4.
Sci Rep ; 9(1): 10391, 2019 Jul 17.
Article in English | MEDLINE | ID: mdl-31316080

ABSTRACT

In recent and future synchrotron radiation facilities, relativistic electron bunches with increasingly high charge density are needed for producing brilliant light at various wavelengths, from X-rays to terahertz. In such conditions, interaction of electron bunches with their own emitted electromagnetic fields leads to instabilities and spontaneous formation of complex spatial structures. Understanding these instabilities is therefore key in most electron accelerators. However, investigations suffer from the lack of non-destructive recording tools for electron bunch shapes. In storage rings, most studies thus focus on the resulting emitted radiation. Here, we present measurements of the electric field in the immediate vicinity of the electron bunch in a storage ring, over many turns. For recording the ultrafast electric field, we designed a photonic time-stretch analog-to-digital converter with terasamples/second acquisition rate. We could thus observe the predicted link between spontaneous pattern formation and giant bursts of coherent synchrotron radiation in a storage ring.

5.
Phys Rev Lett ; 117(17): 174802, 2016 Oct 21.
Article in English | MEDLINE | ID: mdl-27824451

ABSTRACT

Using arbitrary periodic pulse patterns we show the enhancement of specific frequencies in a frequency comb. The envelope of a regular frequency comb originates from equally spaced, identical pulses and mimics the single pulse spectrum. We investigated spectra originating from the periodic emission of pulse trains with gaps and individual pulse heights, which are commonly observed, for example, at high-repetition-rate free electron lasers, high power lasers, and synchrotrons. The ANKA synchrotron light source was filled with defined patterns of short electron bunches generating coherent synchrotron radiation in the terahertz range. We resolved the intensities of the frequency comb around 0.258 THz using the heterodyne mixing spectroscopy with a resolution of down to 1 Hz and provide a comprehensive theoretical description. Adjusting the electron's revolution frequency, a gapless spectrum can be recorded, improving the resolution by up to 7 and 5 orders of magnitude compared to FTIR and recent heterodyne measurements, respectively. The results imply avenues to optimize and increase the signal-to-noise ratio of specific frequencies in the emitted synchrotron radiation spectrum to enable novel ultrahigh resolution spectroscopy and metrology applications from the terahertz to the x-ray region.

6.
Psychiatr Prax ; 32(1): 13-7, 2005 Jan.
Article in German | MEDLINE | ID: mdl-15633070

ABSTRACT

OBJECTIVE: With changed consumer behaviour in the drug scene the psychiatric complications with the derivates of amphetamine increase. In some regions methamphetamin is particularly common. Flashbacks, which can be triggered by psychosocial stress, as well as the age of the usually young patients lead to the differential diagnosis of schizophrenia. METHODS: During the observation period 1998 - 2000 the diagnostic distributions and the psychosocial base data of all patients admitted to the BKH Bayreuth with the clinical picture of a paranoid psychosis, were examined regarding an increase of drug-induced psychosis. RESULTS: Both the number of the treated patients with chronic dependence on methamphetamine as well as acute admissions of patients with drug-induced psychosis increased. Differences to patients diagnosed a schizophrenia could be shown. CONCLUSION: With the further increasing abuse of stimulants like methamphetamine the number of patients with induced psychosis will escalate. Specific settings for treatment will be required to address the addiction as well as the psychosis.


Subject(s)
Amphetamine-Related Disorders/epidemiology , Amphetamine/toxicity , Central Nervous System Stimulants/toxicity , Methamphetamine/toxicity , Psychoses, Substance-Induced/epidemiology , Amphetamine-Related Disorders/diagnosis , Amphetamine-Related Disorders/psychology , Cross-Sectional Studies , Diagnosis, Differential , Forecasting , Germany , Humans , Paranoid Disorders/chemically induced , Paranoid Disorders/diagnosis , Paranoid Disorders/epidemiology , Paranoid Disorders/psychology , Psychoses, Substance-Induced/diagnosis , Psychoses, Substance-Induced/psychology , Schizophrenia/diagnosis
7.
Psychiatr Prax ; 31 Suppl 1: S96-8, 2004 Nov.
Article in German | MEDLINE | ID: mdl-15570517

ABSTRACT

OBJECTIVE AND METHOD: In our paper we report about drug mortality in Bavaria in the years 1990 up to 2002, using statistical trend tests (Spearman rho, Kendall tau). RESULTS: We observed an increase of deaths by illegal drugs in Bavaria as whole, on the other hand also decreases in different parts of the country.


Subject(s)
Drug Overdose/mortality , Illicit Drugs/poisoning , Poisoning/mortality , Cause of Death/trends , Cross-Sectional Studies , Germany , Humans
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