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1.
ChemistryOpen ; 11(5): e202100153, 2022 May.
Article in English | MEDLINE | ID: mdl-34931474

ABSTRACT

We present a combined experimental and theoretical study of the ultrafast transient absorption spectroscopy results of a {Ni2 Dy2 }-compound in DMF, which can be considered as a prototypic molecule for single molecule magnets. We apply state-of-the-art ab initio quantum chemistry to quantitatively describe the optical properties of an inorganic complex system comprising ten atoms to form the chromophoric unit, which is further stabilized by surrounding ligands. Two different basis sets are used for the calculations to specifically identify two dominant peaks in the ground state. Furthermore, we theoretically propagate the compound's correlated many-body wavefunction under the influence of a laser pulse as well as relaxation processes and compare against the time-resolved absorption spectra. The experimental data can be described with a time constant of several hundreds of femtoseconds attributed to vibrational relaxation and trapping into states localized within the band gap. A second time constant is ascribed to the excited state while trap states show lifetimes on a longer timescale. The theoretical propagation is performed with the density-matrix formalism and the Lindblad superoperator, which couples the system to a thermal bath, allowing us to extract relaxation times from first principles.

2.
J Phys Chem Lett ; 11(7): 2592-2597, 2020 Apr 02.
Article in English | MEDLINE | ID: mdl-32163709

ABSTRACT

In this work, using ab initio many-body theory and inspired by an idea suggested by G. D. Mahan for an abstract N-dimensional chain composed of s-type atoms ( Phys. Rev. Lett. 2009, 102, 016801), we propose a functional topological spin-charge gearbox based on the real synthesized Co3Ni(EtOH) cluster driven with laser pulses. We analyze the implications arising from the use of a real molecule with d-character functional orbitals rather than an extended system and discuss the role of the point group symmetry of the system and the transferability of the electronic and spin density between different many-body states using specially designed laser pulses. We thus find that first-row transition-metal elements can host unpaired yet correlated d electrons and thus act as sites for spin information carriers, while designated laser pulses induce symmetry operations leading to a realizable spin-charge gearbox.

3.
Hautarzt ; 70(11): 854-863, 2019 Nov.
Article in German | MEDLINE | ID: mdl-31584113

ABSTRACT

The project "Pain-free Hospital" was the first attempt to improve the level of postoperative care by standardizing pain therapy standards (concepts) in the individual surgical disciplines. Dermatosurgery is no exception. In addition to drug therapy, it is also important to consider biopsychosocial aspects of the symptom pain, as this is the only way to prevent chronification of acute pain in the further course of a disease. Drug therapy should not only be adapted to the classic WHO system (only considering pain intensity), but should also address aspects of pain quality. In this article, we discuss these aspects in more detail and present our treatment concept for dermatosurgery.


Subject(s)
Dermatologic Surgical Procedures , Pain Management/methods , Pain, Postoperative/therapy , Pain , Humans , Pain Measurement
4.
Hautarzt ; 69(1): 48-57, 2018 Jan.
Article in German | MEDLINE | ID: mdl-28983646

ABSTRACT

In order to avoid chronification of pain, appropriate treatment has to be started as early as possible. Inpatient dermatology patients not only suffer from old age and associated multimorbidities but also from characteristic pain due to distinct dermatological diseases. In many cases clinicians have little experience with specific pain treatment but instead have many concerns about how to deal with analgesics. So far chronic pain has been treated according to the pain ladder of the World Health Organization (WHO), which prioritizes the intensity of pain. This article presents an easily implementable concept of pain therapy with special emphasis on the quality of pain. This provides information on whether it is neuropathic or nociceptive pain, which can ultimately be differentially treated. The primary aim is to provide treating dermatologists with a concept to assist in the initiation of an efficient and correct pain therapy. This brief introduction of an individualized pain treatment can reduce the risk of chronification of pain, which can severely impair the quality of life particularly in dermatology patients and also the frequent stigmatization due to the dermatosis.


Subject(s)
Ambulatory Care , Dermatology , Skin Diseases/therapy , Analgesics/therapeutic use , Analgesics, Opioid/therapeutic use , Chronic Pain/classification , Chronic Pain/therapy , Drug Therapy, Combination , Early Medical Intervention , Humans , Neuralgia/classification , Neuralgia/therapy , Nociceptive Pain/classification , Nociceptive Pain/therapy , Pain Measurement , Pain, Postoperative/classification , Pain, Postoperative/therapy , Patient Care Team , Referral and Consultation , Skin Diseases/classification
5.
J Chem Phys ; 143(17): 174303, 2015 Nov 07.
Article in English | MEDLINE | ID: mdl-26547166

ABSTRACT

We present a systematic analysis of the ab initio controlled femtosecond spin dynamics in Ni3(CH3OH) and Co3(+)(CH3OH) clusters achieved by a spin-orbit-coupling enabled Λ process. The distortion caused by the attachment of CH3OH to one of the active magnetic centers of the Ni3 and the Co3(+) clusters induces asymmetric geometries which result in well localized spin densities on the magnetic centers. With the use of high-level quantum chemistry methods, successful spin-flip scenarios are demonstrated for both clusters. In order to assess the experimental accessibility of those effects, we compute their tolerance with respect to two laser pulse parameters, i.e., the energy detuning as well as the deviation of the polar angle ϕ from its optimized value. Finally, we calculate the magneto-optical Kerr effect in order to connect to the susceptibility tensor χ as an experimentally measurable quantity.

6.
Urologe A ; 54(6): 887-99; quiz 900, 2015 Jun.
Article in German | MEDLINE | ID: mdl-26081822

ABSTRACT

Stress urinary incontinence in men is predominantly iatrogenic whereby radical prostatectomy is the most common cause with persistent stress urinary incontinence rates varying between 10 % and 25 %. The first line therapy for postoperative male stress urinary incontinence is physiotherapy, especially pelvic floor muscle rehabilitation. If conservative treatment fails to show sufficient improvement, surgical therapy is recommended. Several treatment options are currently available for the surgical treatment of male stress urinary incontinence including artificial sphincters, adjustable and functional sling systems, bulking agents and implantable balloon systems.


Subject(s)
Exercise Therapy/methods , Prostatectomy/adverse effects , Suburethral Slings , Urinary Incontinence, Stress/etiology , Urinary Incontinence, Stress/therapy , Urinary Sphincter, Artificial , Evidence-Based Medicine , Humans , Male , Treatment Outcome
7.
Urologe A ; 53(6): 847-53, 2014 Jun.
Article in German | MEDLINE | ID: mdl-24903836

ABSTRACT

Today, for the surgical treatment of postprostatectomy incontinence, several treatment options are available, e.g., adjustable and functional sling systems, artificial sphincter, bulking agents, and balloons. However, no recommendations in terms of specific diagnostic tools and differentiated treatment options for everyday life are available. Our aim is to provide some clinically relevant recommendations for the necessary diagnostic workup and different treatment options of postprostatetectomy incontinence to support clinical decisions in everyday life. Treatment selection should be based on contraindications. However, there is a broad overlap of the various surgical options.


Subject(s)
Diagnostic Techniques, Urological/standards , Practice Guidelines as Topic , Prostatectomy/adverse effects , Prostatectomy/standards , Suburethral Slings/standards , Urinary Incontinence, Stress/diagnosis , Urinary Incontinence, Stress/therapy , Germany , Humans , Urinary Incontinence, Stress/etiology
8.
Urologe A ; 53(8): 1175-80, 2014 Aug.
Article in German | MEDLINE | ID: mdl-24824468

ABSTRACT

BACKGROUND: In addition to artificial sphincters, male slings are recommended in the current guidelines for the treatment of persistent male stress incontinence. Today, several sling systems are available. Well-known complications of all sling systems are infections, erosion, residual urine/urinary retention, de novo urgency, and postoperative pain. DISCUSSION: Compared to retropubic implanted adjustable sling systems or functional slings, pain is more common after transobturatoric implantation of adjustable sling systems. Early postoperative pain is very common. In contrast, persistent pain is rare. However, the treatment of persistent pain is a large challenge for urologists and patients. There are no recommendations for diagnostic workup or treatment. RESULTS: After pain classification, pain management should be started with nonsteroidal anti-inflammatory drugs and/or tricyclic antidepressive agents, if necessary treatment escalation with a weak opioid and if not effective interventional procedures should be performed. Sling explantation is only necessary in rare cases.


Subject(s)
Chronic Pain/diagnosis , Chronic Pain/therapy , Pain Measurement/standards , Suburethral Slings/adverse effects , Urinary Incontinence/therapy , Urology/standards , Chronic Pain/etiology , Germany , Humans , Male , Practice Guidelines as Topic , Suburethral Slings/standards , Treatment Outcome , Urinary Incontinence/complications
9.
Urologe A ; 53(3): 339-40, 342, 344-5, 2014 Mar.
Article in German | MEDLINE | ID: mdl-24522693

ABSTRACT

Postprostatectomy incontinence (PPI) is one of the most feared complications of radical prostatectomy with major impact on quality of life and social well-being. In recent years due to improved surgical techniques a reduction of the postoperative incontinence rate was achieved. However, due to the increasing number of radical prostatectomies performed for prostate cancer, a substantial and increasing number of patients are suffering from postoperative stress urinary incontinence. If conservative treatment fails, surgical therapy is recommended. For decades, the artificial urinary sphincter was the reference standard for moderate to severe postoperative male stress urinary incontinence. However, patients' demand on minimally invasive treatment options is high. Age or advanced prostate cancer should not be an exclusion criterion for surgical treatment of persistent PPI.


Subject(s)
Men's Health , Minimally Invasive Surgical Procedures/methods , Prostatectomy/adverse effects , Suburethral Slings , Urinary Incontinence, Stress/etiology , Urinary Incontinence, Stress/surgery , Urologic Surgical Procedures, Male/methods , Humans , Male , Plastic Surgery Procedures/instrumentation , Plastic Surgery Procedures/methods , Urologic Surgical Procedures, Male/instrumentation
10.
Phys Rev Lett ; 109(26): 267209, 2012 Dec 28.
Article in English | MEDLINE | ID: mdl-23368615

ABSTRACT

We present a combined theoretical and experimental study of spin and charge dynamics on the homodinuclear compound [Ni2(II)(L-N4Me2)(emb)]. The theoretically calculated oscillator strengths of the ground-state absorption spectrum show an acceptable agreement with experiment. We predict a local ultrafast laser-induced spin-flip scenario, which involves charge-transfer states. Experimentally, we observe charge dynamics on two different time scales. The two relevant, transient electronic states and their electronic properties are also theoretically characterized. These results provide a joint investigation of the homodinuclear complex and suggest a realistic scenario for ultrafast spin dynamics and other optical-related manipulations.

11.
J Phys Chem A ; 115(10): 1774-80, 2011 Mar 17.
Article in English | MEDLINE | ID: mdl-21332233

ABSTRACT

We present a fully ab initio calculation, the synthesis and the characterization of the homodinuclear [Ni(2)(II)(L-N(4)Me(2))(emb)] complex, which can act as a prototypic, realistic substance for ultrafast laser-induced spin dynamics. The new compound, which has been synthesized and characterized, consists of two magnetic centers with different spin properties and different local symmetries (distorted octahedral versus distorted square-planar) and exhibits strong spin localization. We calculate the vibrational and electronic spectra of the compound and predict a local spin-flip scenario. The very existence and the properties of the compound represent an important step toward ultrafast experimental spin dynamics in ligand-stabilized multicenter compounds and paves the path toward laser-induced magnetic logic on a single molecule.

12.
Urologe A ; 49(4): 511-4, 2010 Apr.
Article in German | MEDLINE | ID: mdl-20376653

ABSTRACT

The principle of adjustment with the possibility to react to changing needs of specific patients even years after placing an implant is convincing. Experience has taught that urodynamic parameters as well as personal demands of a patient may change individually for instance as a result of resuming physical activities. Such demands can be met by simple adjustment.Results of Argus and Remeex can be considered equally sustainable as first publications date back from 2006 and 2004. With follow-up periods of more than 2 years realistic success rates of up to 90% have been observed. Adjustment will be needed in one third of cases.The ProAct balloons are attractive by virtue of the low invasiveness of both implantation and adjustment. A series published in 2005 revealed a success rate of 77%; these experiences have been confirmed by several other papers. Limiting factors for ProAct are irradiation therapy and scarred bladder neck.


Subject(s)
Suburethral Slings , Urinary Incontinence, Stress/surgery , Equipment Design , Humans , Male , Postoperative Complications/physiopathology , Surgical Mesh , Suture Techniques , Urinary Incontinence, Stress/physiopathology , Urodynamics/physiology
13.
Phys Rev Lett ; 103(21): 217401, 2009 Nov 20.
Article in English | MEDLINE | ID: mdl-20366066

ABSTRACT

In an ultrafast laser-induced magnetization-dynamics scenario we demonstrate for the first time an exact microscopic spin-switch mechanism. Combining ab initio electronic many-body theory and quantum optics analysis we show in detail how the coherently induced material polarization for every elementary process leads to angular-momentum exchange between the light and the irradiated antiferromagnetic NiO. Thus we answer the long-standing question where the angular momentum goes. The calculation also predicts a dynamic Kerr effect, which provides a signature for monitoring spin dynamics, by simply measuring the transient rotation and ellipticity of the reflected light.

14.
Phys Rev Lett ; 100(11): 116103, 2008 Mar 21.
Article in English | MEDLINE | ID: mdl-18517800

ABSTRACT

The electronic properties of a Na9+ cluster are markedly changed when deposited on a Cu(001) surface. Particularly, the lifetime of the (hybridized) single-particle electronic states are drastically enhanced indicating a change in electronic correlations upon absorption. To capture this effect, we developed a Green's function approach based on the configuration interaction technique. The calculated lifetimes (16.5 to 33 fs) of excited electronic states are in line with experimental observations. Our new method demonstrates the feasibility of accounting accurately for electronic correlation in large, nonperiodic systems.

15.
Phys Rev Lett ; 95(7): 077401, 2005 Aug 12.
Article in English | MEDLINE | ID: mdl-16196821

ABSTRACT

In this Letter we develop a new systematic approach to study optical second harmonic generation in NiO, on both the (001) surface and the bulk. NiO is modeled as a doubly embedded cluster on which two highly correlated quantum chemistry methods are applied in order to obtain the wave functions of all the intragap d states and the low lying charge transfer states. The optical gap is calculated and the electric dipole, magnetic dipole, and electric quadrupole contributions to the second order susceptibility tensor are computed for the first time from first principles. Going beyond the electric dipole approximation gives new insight into the experimentally observed spectrum. A method is proposed for monitoring the spin dynamics of the NiO(001) surface.

16.
Int J Artif Organs ; 28(1): 66-73, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15742312

ABSTRACT

Fourier transform infrared microscopy was used to investigate human cortical bone samples before and after treatment with increasing doses of X-ray radiation. Especially the spectral region of the v1 and v3 phosphate vibrations of hydroxyapatite, the main mineral component of bone, and the region of the amide I and amide II vibrational bands due to the collagen extracellular matrix were examined. Major spectral changes in the phosphate region between 1250-1000 cm(-1) occur after irradiation doses between 1 and 4 Gray. These findings are explained by a decrease in size of mineral crystallites and by variances of the toichiometric/non-stoichiometric apatite composition. The Ca2+ /PO4(3-) /HPO4(2-) composition in the biological apatite is altered near the bone surface. The secondary structure of the collagen matrix is not affected by cumulative irradiation up to doses of 15 Gray as indicated by the unchanged frequency maximum and contour shape of the amide I band between 1600-1700 cm(-1) . However, side chain carboxylate groups of the collagen matrix that are involved in coordination with apatite bound calcium ions are partially removed by decarboxylation upon irradiation. Concomitantly, a loss of acidic phosphate groups due to a formation of phosphate groups with bound calcium is observed. These changes on a molecular level can be correlated with alterations in the mechanical properties of the bone samples, e.g. with an increased embrittlement as deduced from experiments with a scanning acoustic microscope.


Subject(s)
Bone and Bones/radiation effects , Amides/chemistry , Amides/radiation effects , Bone and Bones/chemistry , Calcium/chemistry , Calcium/radiation effects , Carboxylic Acids/chemistry , Carboxylic Acids/radiation effects , Collagen/chemistry , Collagen/radiation effects , Crystallography , Durapatite/chemistry , Durapatite/radiation effects , Humans , Microspectrophotometry , Phosphates/chemistry , Phosphates/radiation effects , Radiation Dosage , Spectroscopy, Fourier Transform Infrared , X-Rays
17.
Phys Rev Lett ; 92(22): 227402, 2004 Jun 04.
Article in English | MEDLINE | ID: mdl-15245259

ABSTRACT

Combining optical control theory with ab initio quantum chemistry and electronic crystal field theory we explore the laser induced femtosecond spin dynamics. We propose a scenario for ultrafast all-optical magnetic switching that results from the combination of spin-orbit coupling with appropriately shaped short laser pulses. We find that the application of the theory to the multiplet states within the gap of NiO(001) predicts for the first time the possibility of all-optical spin switching within 100 fs. The switching can be observed using any of the multiplets as the intermediate state.

18.
J Urol ; 166(2): 449-52, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11458045

ABSTRACT

PURPOSE: Symptomatic nephroptosis is a rare disease requiring surgical therapy only in select cases. Laparoscopic nephropexy has been reported as minimally invasive treatment for symptomatic patients. We evaluated our long-term outcome after laparoscopic fixation of the kidney with an alloplastic mesh graft. MATERIALS AND METHODS: Since 1992, 30 patients have undergone laparoscopic transperitoneal nephropexy for symptomatic nephroptosis. All patients were preoperatively investigated by excretory urography (IVP) and split renal scan in the supine and upright positions. For fixing the kidney to the abdominal wall a polyglactin and polypropylene mesh graft was used in 6 and 24 cases, respectively. A total of 17 patients with a minimum followup of 5 years participated in an assessment of long-term outcome. Clinical examination, IVP and split renal function testing were performed with patients lying and standing. Patients were further questioned about postoperative satisfaction and whether they would undergo the procedure again. RESULTS: Of 17 patients 10 completed all investigations, 3 were contacted by telephone and 4 were lost to followup. Median followup was 5.9 years. Improvement in symptoms was reported in all cases with complete relief in 11 and intermittent flank pain requiring no medication in 2. There were no postoperative urinary tract infections or hematuria observed with improved hypertension requiring no postoperative medication in 1 case. Postoperatively IVP showed no recurrence in 8 of 10 patients but there was 5 cm. or greater recurrent ptosis in 2. Recurrence developed after using the polyglactin and polypropylene mesh grafts. Comparing preoperative and postoperative (123)iodine renal scans revealed significant improvement in renal function in 9 cases (p <0.05). There was no postoperative difference in split renal function and only 1 patient did not improve. No complications were noted except 1 symptomatic recurrence 3 months after the initial operation that required open surgical fixation. A total of 11 patients were completely satisfied with the long-term outcome and 2 were moderately satisfied. Of the patients 12 would undergo the procedure again, including 2 with persistent slight flank pain. One patient was inconsistent in regard to whether she would undergo the procedure again. CONCLUSIONS: Symptomatic nephroptosis is a bothersome disease requiring therapy only after thorough evaluation, including IVP and split renal scan with patients supine and upright. The good clinical outcome and highly satisfactory cosmetic result support laparoscopic nephropexy as the treatment of choice. Short-term and long-term results prove the efficacy of renal fixation with alloplastic mesh graft as minimally invasive therapy with a high success rate.


Subject(s)
Kidney Diseases/surgery , Kidney/surgery , Laparoscopy , Adult , Female , Follow-Up Studies , Humans , Kidney Diseases/diagnostic imaging , Middle Aged , Patient Satisfaction , Postoperative Complications , Radiography , Reoperation , Surgical Mesh , Treatment Outcome
19.
Phytother Res ; 15(4): 367-70, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11406865

ABSTRACT

The value of an extract of Hypericum perforatum (St John's wort) for children with mild to moderate depressive symptoms was investigated for the first time in a multi-centre post-marketing surveillance study. One hundred and one children under 12 years were treated for a minimum of 4 weeks with an extension to 6 weeks with parental consent and medical practitioner recommendation. the dosage used ranged from 300 to 1800 mg per day. Compliance, tolerability and efficacy were assessed every 2 weeks by physicians and parents. Based on the data available for analysis, the number of physicians rating effectiveness as 'good' or 'excellent' was 72% after 2 weeks, 97% after 4 weeks and 100% after 6 weeks. The ratings by parents were very similar. There was, however, an increasing amount of missing data at each assessment point with the final evaluation including only 76% of the initial sample. Tolerability was good and no adverse events were reported. The results of this study suggest that Hypericum is a potentially safe and effective treatment for children with symptoms of depression.


Subject(s)
Antidepressive Agents/therapeutic use , Depression/prevention & control , Hypericum/therapeutic use , Phytotherapy , Plants, Medicinal , Child , Child, Preschool , Female , Humans , Infant , Male , Patient Compliance , Surveys and Questionnaires , Treatment Outcome
20.
Mol Biol Cell ; 11(11): 3885-96, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11071914

ABSTRACT

The bidirectional nucleocytoplasmic transport of macromolecules is mediated by the nuclear pore complex (NPC) which, in yeast, is composed of approximately 30 different proteins (nucleoporins). Pre-embedding immunogold-electron microscopy revealed that Nic96p, an essential yeast nucleoporin, is located about the cytoplasmic and the nuclear periphery of the central channel, and near or at the distal ring of the yeast NPC. Genetic approaches further implicated Nic96p in nuclear protein import. To more specifically explore the potential role of Nic96p in nuclear protein import, we performed a two-hybrid screen with NIC96 as the bait against a yeast genomic library to identify transport factors and/or nucleoporins involved in nuclear protein import interacting with Nic96p. By doing so, we identified the yeast nucleoporin Nup53p, which also exhibits multiple locations within the yeast NPC and colocalizes with Nic96p in all its locations. Whereas Nup53p is directly involved in NLS-mediated protein import by its interaction with the yeast nuclear import receptor Kap95p, it appears not to participate in NES-dependent nuclear export.


Subject(s)
Fungal Proteins/metabolism , Membrane Proteins , Nuclear Pore Complex Proteins , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Porins/genetics , Porins/metabolism , Saccharomyces cerevisiae Proteins , Yeasts/metabolism , Active Transport, Cell Nucleus , Cell Nucleus/metabolism , Cell Nucleus/ultrastructure , Fungal Proteins/genetics , Gene Deletion , Microscopy, Immunoelectron , Mutation , Nuclear Localization Signals , Two-Hybrid System Techniques , Yeasts/genetics , beta Karyopherins
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