110,510 research outputs found
Faust : Eine Satire / von H. E. Jahn
No full textFAUST : EINE SATIRE / VON H. E. JAHN
Faust : Eine Satire / von H. E. Jahn (1)
Cover (1)
Widmung (5)
Faust. Eine Satire (7
View from the bridge: a pseudo-Jahn-Teller approach to transition metal hydrosilane complexes
No full textThe model complex [Cp(CO)(2)Mn(SiH4)] has been studied by time-dependent DFT methods: hence, it is shown to be unstable with respect to a pseudo-Jahn-Teller distortion which brings an equatorial Si-H moiety into contact with the Mn centre.</p
The effect of cooperative Jahn–Teller interactions on C60− anions
No full textSingly charged buckminsterfullerene anions, C60−, are subject to a strong intramolecular T [circle times] h Jahn–Teller (JT) effect. When such ions interact with other C60− ions in a solid through a cooperative JT effect, they will be subject to an additional interaction. There are a number of different mechanisms that can cause this interaction. However, in the molecular field approximation, all can be modelled phenomenologically in terms of a symmetry-lowering interaction written in terms of a linear combination of electronic operators for the h modes involved in the intramolecular JT effect. We will consider the combined effect of this distortion and the intramolecular JT effect. We will analyse the lowest adiabatic potential energy surface, and calculate the energies of the resultant vibronic states. The results are shown to have a complicated dependence on the particular combination of h modes chosen, and the energies of the resultant vibronic states cannot easily be deduced from the form of the potential alone
Population-level effect of HIV on adult mortality and early evidence of reversal after introduction of antiretroviral therapy in Malawi.
No full textBACKGROUND: Malawi, which has about 80,000 deaths from AIDS every year, made free antiretroviral therapy available to more than 80 000 patients between 2004 and 2006. We aimed to investigate mortality in a population before and after the introduction of free antiretroviral therapy, and therefore to assess the effects of such programmes on survival at the population level. METHODS: We used a demographic surveillance system to measure mortality in a population of 32,000 in northern Malawi, from August, 2002, when free antiretroviral therapy was not available in the study district, until February, 2006, 8 months after a clinic opened. Causes of death were established through verbal autopsies (retrospective interviews). Patients who registered for antiretroviral therapy at the clinic were identified and linked to the population under surveillance. Trends in mortality were analysed by age, sex, cause of death, and zone of residence. FINDINGS: Before antiretroviral therapy became available in June, 2005, mortality in adults (aged 15-59 years) was 9.8 deaths for 1000 person-years of observation (95% CI 8.9-10.9). The probability of dying between the ages of 15 and 60 years was 43% (39-49) for men and 43% (38-47) for women; 229 of 352 deaths (65.1%) were attributed to AIDS. 8 months after the clinic that provided antiretroviral therapy opened, 107 adults from the study population had accessed treatment, out of an estimated 334 in need of treatment. Overall mortality in adults had decreased by 10% from 10.2 to 8.7 deaths for 1000 person-years of observation (adjusted rate ratio 0.90, 95% CI 0.70-1.14). Mortality was reduced by 35% (adjusted rate ratio 0.65, 0.46-0.92) in adults near the main road, where mortality before antiretroviral therapy was highest (from 13.2 to 8.5 deaths per 1000 person-years of observation before and after antiretroviral therapy). Mortality in adults aged 60 years or older did not change. INTERPRETATION: Our findings of a reduction in mortality in adults aged between 15 and 59 years, with no change in those older than 60 years, suggests that deaths from AIDS were averted by the rapid scale-up of free antiretroviral therapy in rural Malawi, which led to a decline in adult mortality that was detectable at the population level
A new approach to analyse H⊗(2h⊕g) Jahn-Teller system for C
No full textIt is now well-known that electron (hole)-vibron coupling and hence Jahn-Teller (JT)
effect is important understanding the properties of C60 and related molecules. In this paper, we study H⊗(2) coupling case to find the potential energy surfaces for the positively charged C60 molecule due to distortion. The H⊗(2) Jahn-Teller system is of particular importance as this will be the JT effect displayed by C60 molecules removed with an electron. C is obtained by removing one electron from fivefold degenerate Hu highest occupied molecular orbital (HOMO) and a hole in HOMO interacts with the vibrational modes of C60 and symmetry is broken. We apply the method of symmetry breaking mechanism to obtain expressions for the potential energy surface
Als Der Wohl-Ehrenveste, und Wohl-Fürnehme Herr Joh. Christoph Jahn, Bürger und Handels-Mann in Leipzig, Sich mit Der ... Jungfer Johanna Dorothea Müllerin ... zu Torgau den 13. Novembr. Anno 1703. Ehlich trauen ließ, Wolte, ihre Schuldigkeit gebührender massen zu bezeugen, Nachfolgende Zeilen überreichen Zwey Des Herrn Bräutigams verbundenste Diener
No full textHochzeitsgedichte auf Johann Christoph Jahn, Kaufmann in Leipzig, und Johanna Dorothea Müller aus Torgau, 13. Nov. 1703Enth. 2 Glückwunschgedichte der BeiträgerAutopsie nach dem Ex. der ULB Sachsen-AnhaltVorlageform des Erscheinungsvermerks: Lejpzjg, Gedruckt bey Christian Göze
Verlag der Aktien-Gesellschaft vormals H. Gladenbeck & Sohn Bildgiesserei Berlin-Friedrichshagen-Leipzig, Nathan der Weise von Adolf Jahn, Castell. Marmor od. Bronze
No full textVERLAG DER AKTIEN-GESELLSCHAFT VORMALS H. GLADENBECK & SOHN BILDGIESSEREI BERLIN-FRIEDRICHSHAGEN-LEIPZIG, NATHAN DER WEISE VON ADOLF JAHN, CASTELL. MARMOR OD. BRONZE
Verlag der Aktien-Gesellschaft vormals H. Gladenbeck & Sohn Bildgiesserei Berlin-Friedrichshagen-Leipzig, Nathan der Weise von Adolf Jahn, Castell. Marmor od. Bronze ( -
SPIN ORBIT COUPLING JAHN-TELLER (SOCJT)
No full textAuthor Institution: Corporate Strategic Research; ExxonMobil Research and Engineering, University of North Carolina; Dept. of Chemistry, The Ohio State UniversitySOCJT is a PC based program for determining the lowest energy eigenvalues of the Jahn-Teller Hamiltonian including linear and quadratic Jahn-Teller and spin-orbit terms. Calculations may be run for any molecule with non-cubic symmetry, having n arbitrary Jahn-Teller active modes, and arbitrary integer or half-integer spin state. In addition to calculating the lowest energy eigenvalues, SOCJT also computes several properties derived from the resulting eigenvectors, including the Coriolis coupling constants and the relative vibronic transition intensities to another electronic state. For the purpose of fitting experimental spectra, a non-linear least squares routine is included which allows for the fitting of the spin orbit coupling constant, , the n linear Jahn-Teller coupling constants , the n quadratic Jahn-Teller coupling constants , the n unperturbed harmonic vibrational frequencies, , and the n unperturbed anharmonic corrections , to experimentally determined line positions. SOCJT has been used successfully to fit the spectra of several Jahn-Teller active molecules, including , , , and
The role of the Jahn-Teller coupling in dissociative recombination of H<sub>3</sub>O<sup>+</sup>and H ions
No full textWe discuss the importance of the non Born-Oppenheimer Jahn-Teller coupling in the dissociative recombination of H3O+ and H 3+ ions with low energy electrons. The coupling is known to be important for dissociative recombination of H3+, for which detailed and simplified theoretical models have been previously developed. In this study we discuss how the detailed theoretical model reproduces individual resonances in the experimental spectrum of H 3+. We present a simplified theoretical model of the dissociative recombination of H3O+. Similarly to H 3+, we consider the Jahn-Teller coupling as a key factor responsible for the capture of the electron into a Rydberg state associated with excited vibrational levels of the ion. We use a simplified Jahn-Teller model for highly symmetrical ions (not only for H3O+ and H 3+) and adopt the normal mode approximation for the vibrational states of H3O+. Using the multi-channel quantum defect formalism and accurate ab initio calculations, we derive the cross sections for electron capture by the ion that is initially in the ground vibrational level. In our approximation, once the electron is captured by the ion, the autoionization probability is neglected compared to the predissociation probability. This allows us to evaluate the cross section for the dissociative recombination of H3O+ using just a few parameters obtained from ab initio calculation. The total cross section obtained is in good agreement with data from storage ring experiments
Estimating the need for antiretroviral treatment and an assessment of a simplified HIV/AIDS case definition in rural Malawi.
No full textBACKGROUND: Surveillance in the era of antiretroviral therapy (ART) requires estimates of HIV prevalence as well as the proportion eligible for ART. We estimated HIV prevalence and assessed field staging of individuals to estimate the burden of HIV disease needing treatment in rural Malawi. METHODS: Adults aged 18-59 years in a demographic surveillance system were interviewed, examined, and HIV counselled and tested. Staging that used a simplified version of the WHO criteria ('field checklist') was compared with staging by a medical assistant using a 'clinic checklist' and to CD4 cell results. RESULTS: A total of 2129 of 2303 eligible adults (92.4%) were traced, and 2047 (96.1%) participated. Of the 1443 participants (70.5%) tested, 11.6% were HIV positive. ART eligibility classification by the field and clinic checklists were concordant in 122 of 133 HIV-positive individuals. Compared with the clinic checklist, the field checklist had a sensitivity of 50% and a specificity of 96%. Including those already known to be on ART, staging by the field and clinic checklists estimated ART eligibility at 16.3 and 17.7% of HIV-positive individuals, respectively. Using CD4 cell count under 250 cells/mul or WHO stage III/IV, the Malawi national programme criteria, 38% of HIV-positive individuals were eligible for ART, compared with 31% based on the 2006 WHO criteria of CD4 cell count under 200 cells/mul or WHO stage IV or CD4 cell count of 200-350 cells/mul and WHO stage III. CONCLUSION: The field checklist was not a suitable tool for individual staging. Criteria for ART eligibility based on clinical staging alone missed two-thirds of those eligible by clinical staging and CD4 cell count
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