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1.
Phys Rev Lett ; 131(18): 183002, 2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37977634

ABSTRACT

Careful control of quantum states is a gateway to research in many areas of science such as quantum information, quantum-controlled chemistry, and astrophysical processes. Precise optical control of molecular ions remains a challenge due to the scarcity of suitable level schemes, and direct laser cooling has not yet been achieved for either positive or negative molecular ions. Using a cryogenic wire trap, we show how the internal quantum states of C_{2}^{-} anions can be manipulated using optical pumping and inelastic quenching collisions with H_{2} gas. We obtained optical pumping efficiencies of about 96% into the first vibrational level of C_{2}^{-} and determined the absolute inelastic rate coefficient from v=1 to 0 to be k_{q}=(3.2±0.2_{stat}±1.3_{sys})×10^{-13} cm^{3}/s at 20(3) K, over 3 orders of magnitude smaller than the capture limit. Reduced-dimensional quantum scattering calculations yield a small rate coefficient as well, but significantly larger than the experimental value. Using optical pumping and inelastic collisions, we also realized fluorescence imaging of negative molecular ions. Our work demonstrates high control of a cold ensemble of C_{2}^{-}, providing a solid foundation for future work on laser cooling of molecular ions.

2.
Article in English | MEDLINE | ID: mdl-36901561

ABSTRACT

(1) Presentations to a trauma emergency department following a violent confrontation account for a relevant proportion of the overall population. To date, violence (against women) in the domestic setting has been studied in particular. However, representative demographic and preclinical/clinical data outside of this specific subgroup on interpersonal violence are limited; (2) Patient admission records were searched for the occurrence of violent acts between 1 January and 31 December 2019. A total of 290 patients out of over 9000 patients were retrospectively included in the "violence group" (VG). A "typical" traumatologic cohort (presentation due to, among other things, sport-related trauma, falls, or traffic accidents) who had presented during the same period served as comparison group. Then, differences in the type of presentation (pedestrian, ambulance, or trauma room), time of presentation (day of week, time of day), diagnostic (imaging) and therapeutic (wound care, surgery, inpatient admission) measures performed, and discharge diagnosis were examined; (3) A large proportion of the VG were male, and half of the patients were under the influence of alcohol. Significantly more patients in the VG presented via the ambulance service or trauma room and during the weekend and the night. Computed tomography was performed significantly more often in the VG. Surgical wound care in the VG was required significantly more often, with injuries to the head being the most common; (4) The VG represents a relevant cost factor for the healthcare system. Because of the frequent head injuries with concomitant alcohol intoxication, all mental status abnormalities should be attributed to brain injury rather than alcohol intoxication until proven otherwise, to ensure the best possible clinical outcome.


Subject(s)
Alcoholic Intoxication , Wounds and Injuries , Humans , Male , Female , Alcoholic Intoxication/epidemiology , Retrospective Studies , Universities , Emergency Service, Hospital , Violence
3.
Molecules ; 28(3)2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36770793

ABSTRACT

In this paper, we show the influence of the chemical structure of four different conformers on the secondary electron emission and backscattering of an electron beam from a gel of methacrylic acid. The conformers have different permanent dipole moments, which determines the cross sections for elastic collisions with electrons. The cross sections are used in Monte Carlo simulations of an electron beam, which enters the gel of methacrylic acid. The secondary electron yield and the backscattering coefficient are computed as a function of the beam energy.

4.
Front Med (Lausanne) ; 8: 678382, 2021.
Article in English | MEDLINE | ID: mdl-34568354

ABSTRACT

Background: The inflammatory response and post-traumatic complications like infections play an important role in the pathophysiology of severe injuries. This study examines the microbiological aspects in anti-infective treatment of trauma patients and their inflammatory response in post-traumatic infections complications. Patients and Methods: A retrospective analysis of prospectively collected data in trauma patients (ISS ≥ 16) over a 1-year period (01/2018 to 12/2018) is provided. Patient population was stratified into severely injured patients without post-traumatic infection (inf-PT), and severely injured patients who developed an infection (inf+PT). Results: Of 114 trauma patients, 45 suffered from post-traumatic infection during the first 10 days of hospitalization. Severely injured patients with concomitant traumatic brain injury (PT+TBI) showed the highest rate of post-traumatic infection. Pro-inflammatory reaction was tracked by levels of Interleukin (IL-)6 (day 3: inf+T 190.8 ± 359.4 pg/dL > inf-PT 56.2 ± 57.7 pg/mL (mean ± SD); p = 0.008) and C-Reactive-Protein (CRP, day 3: inf+PT 15.3 mg/dL > inf-PT 6.7 mg/dL, p = 0.001) which were significantly higher in trauma patients who develop an infectious complication and showed a significant positive correlation with the occurrence of infection. The leading entity of infection was pneumonia followed by infections of the urinary tract mainly caused by gram-negative Enterobacteriaceae. 67.5% of all trauma patients received single-shot antibiosis during initial care in trauma bay. The development of secondary colonization was not relevant positively correlated with single-shot antibiosis (r = 0.013, p = 0.895) and prophylactically calculated antibiotic administration (r = 0.066, p = 0.500). Conclusion: Severely injured trauma patients have an increased risk for development of infectious complications, which mainly is pneumonia followed by infection of the urinary tract mainly caused by gram-negative Enterobacteriaceae. Based on the data in this study, the one-time antibiotic and prophylactic calculated use of antibiotics, like Cephalosporins must be critically discussed in terms of their role in the development of post-traumatic infections and microbial selection.

5.
J Chem Phys ; 152(23): 234303, 2020 Jun 21.
Article in English | MEDLINE | ID: mdl-32571047

ABSTRACT

We present an extensive range of quantum calculations for the state-changing rotational dynamics involving two simple molecular anions that are expected to play some role in the evolutionary analysis of chemical networks in the interstellar environments, C2H- (X1Σ+) and C2N- (X3Σ-), but for which inelastic rates are only known for C2H-. The same systems are also of direct interest in modeling selective photo-detachment experiments in cold ion traps where the He atoms function as the chief buffer gas at the low trap temperatures. This study employs accurate, ab initio calculations of the interaction potential energy surfaces for these anions, treated as rigid rotors, and the He atom to obtain a wide range of state-changing quantum cross sections and rates at temperatures up to about 100 K. The results are analyzed and compared for the two systems to show differences and similarities between their rates of state-changing dynamics.

6.
Article in German | MEDLINE | ID: mdl-25832579

ABSTRACT

In therapeutic preliminary talks, the therapist and the adolescent person (the potential patient) are together trying to answer the question of the indication. This is why every preliminary talk is designed like a "trial therapeutical session". The study tries to answer the question of the cognitive organization of the verbalization from a sozio-scientific point of view. A sociological-interpretative approach was chosen to analyse transcripts of recordings of 30 of such therapeutic preliminary sessions, which provide the foundation for the study. The sociological-interpretative method allows it to filter out several phenomenons of verbal interaction, as for example when there is an incongruity of the different perceptions of "everyday life" and "therapy". A speech-style model is used to evaluate the formal result of the indication (as well as of the therapy).


Subject(s)
Psychoanalytic Therapy , Verbal Behavior , Adolescent , Age Factors , Defense Mechanisms , Female , Humans , Male , Narcissism , Personality Assessment , Professional-Patient Relations , Psychoanalytic Interpretation , Semantics , Speech Acoustics , Vocabulary
7.
J Chem Phys ; 137(10): 104301, 2012 Sep 14.
Article in English | MEDLINE | ID: mdl-22979853

ABSTRACT

Radiative association of silicon mononitride (SiN) in its two lowest molecular electronic states is studied through quantum and classical dynamics. Special attention is paid to the behavior of the cross section at high collision energies. A modified expression for the semiclassical cross section is presented which excludes transitions to continuum states. This gives improved agreement with quantum mechanical perturbation theory at high energies. The high energy cross section is overestimated if conventional semiclassical theory is used. The modified semiclassical theory should be valid in general for radiative association transitions from an upper to a lower electronic state. We also implement a quantum dynamical optical potential method with the same type of modification. The rate coefficient is calculated using Breit-Wigner theory and the modified semiclassical formula for the resonance and direct contributions, respectively, for temperatures from 10 K to 20,000 K. A rapid decrease in the rate constant for formation of ground state SiN is observed above 2000 K which was not seen previously.

8.
J Chem Phys ; 130(8): 084304, 2009 Feb 28.
Article in English | MEDLINE | ID: mdl-19256608

ABSTRACT

Quantum chemical calculations are reported for the energies of the few lowest electronic singlet states of oxywater along dissociation of the oxygen-oxygen bond into water and singlet oxygen using multistate multireference second-order Moller-Plesset perturbation theory. We compute an energy of 21 kcal/mol to remove one oxygen atom in the lowest singlet state. The two lowest excited singlet states have vertical excitation energies of 2.64 and 2.96 eV (470 and 419 nm) and are leading to the dissociation of the molecule. The two charge transfer states are accessible at vertical excitation of 4.91 and 5.22 eV (253 and 238 nm).

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