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1.
Phys Rev Lett ; 110(14): 143604, 2013 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-25166988

RESUMEN

Levitated nanospheres in optical cavities open a novel route to study many-body systems out of solution and highly isolated from the environment. We show that properly tuned optical parameters allow for the study of the nonequilibrium dynamics of composite nanoparticles with nonisotropic optical friction. We find optically induced ordering and nematic transitions with nonequilibrium analogs to liquid crystal phases for ensembles of dimers.


Asunto(s)
Cristales Líquidos/química , Nanosferas/química , Óptica y Fotónica/métodos , Cinética , Modelos Teóricos
3.
J Zool (1987) ; 283(3): 186-192, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21552308

RESUMEN

Pigmentation disorders such as albinism are occasionally associated with hearing impairments in mammals. Therefore, we wanted to investigate whether such a phenomenon also exists in non-mammalian vertebrates. We measured the hearing abilities of normally pigmented and albinotic specimens of two catfish species, the European wels Silurus glanis (Siluridae) and the South American bronze catfish Corydoras aeneus (Callichthyidae). The non-invasive auditory evoked potential (AEP) recording technique was utilized to determine hearing thresholds at 10 frequencies from 0.05 to 5 kHz. Neither auditory sensitivity nor shape of AEP waveforms differed between normally pigmented and albinotic specimens at any frequency tested in both species. Silurus glanis and C. aeneus showed the best hearing between 0.3 and 1 kHz; the lowest thresholds were 78.4 dB at 0.5 kHz in S. glanis (pigmented), 75 dB at 1 kHz in S. glanis (albinotic), 77.6 dB at 0.5 kHz in C. aeneus (pigmented) and 76.9 dB at 1 kHz in C. aeneus (albinotic). This study indicates no association between albinism and hearing ability. Perhaps because of the lack of melanin in the fish inner ear, hearing in fishes is less likely to be affected by albinism than in mammals.

4.
J Biomed Mater Res B Appl Biomater ; 81(2): 435-40, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17022062

RESUMEN

This study explored the vulnerability of the ductus deferens due to mesh induced inflammation and shrinkage after hernia repair in the rodent model. Two commonly used types of hernioplastic implants (Prolene and Vypro II) were surgically wrapped around the ductus deferentes on both sides in 20 juvenile and 20 adult Sprague-Dawley rats. Twenty male rats underwent sham surgeries as controls. After 3 months, each male was mated with 2-3 adult females, which were subsequently sacrificed and oocytes or embryos were flushed and counted. Histochemical investigations of the implants and the ductus recovered surgically 4 weeks after implantation (one side) and after the fertility test (second side) were conducted. All groups exhibited 1-3 males with decreased or restricted fertility but there was no difference between groups. Histochemical analysis of the implants and the ductus recovered 4 weeks and 4 months after implantation revealed some sperm granulomes due to lesions of the spermatic cord caused by the implant in the Prolene group. There was no inflammatory reaction in the mucosa or blockage of the spermatic cord visible. Both types of hernioplastic implants tested in this investigation do not give an indication of a negative influence on male fertility in juvenile or adult rats.


Asunto(s)
Fertilidad , Hernia Inguinal/cirugía , Poliglactina 910 , Polipropilenos , Mallas Quirúrgicas , Animales , Materiales Biocompatibles/efectos adversos , Femenino , Reacción a Cuerpo Extraño/metabolismo , Reacción a Cuerpo Extraño/patología , Inflamación/etiología , Inflamación/patología , Masculino , Ensayo de Materiales , Poliglactina 910/efectos adversos , Polipropilenos/efectos adversos , Embarazo , Ratas , Ratas Sprague-Dawley , Cordón Espermático/metabolismo , Cordón Espermático/patología , Mallas Quirúrgicas/efectos adversos , Conducto Deferente/patología
5.
Nat Commun ; 8: 15813, 2017 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-28639614

RESUMEN

There is a significant ongoing effort in realizing quantum annealing with different physical platforms. The challenge is to achieve a fully programmable quantum device featuring coherent adiabatic quantum dynamics. Here we show that combining the well-developed quantum simulation toolbox for Rydberg atoms with the recently proposed Lechner-Hauke-Zoller (LHZ) architecture allows one to build a prototype for a coherent adiabatic quantum computer with all-to-all Ising interactions and, therefore, a platform for quantum annealing. In LHZ an infinite-range spin-glass is mapped onto the low energy subspace of a spin-1/2 lattice gauge model with quasi-local four-body parity constraints. This spin model can be emulated in a natural way with Rubidium and Caesium atoms in a bipartite optical lattice involving laser-dressed Rydberg-Rydberg interactions, which are several orders of magnitude larger than the relevant decoherence rates. This makes the exploration of coherent quantum enhanced optimization protocols accessible with state-of-the-art atomic physics experiments.

6.
Wien Klin Wochenschr ; 91(23): 798-801, 1979 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-543142

RESUMEN

Fifty pregnant women admitted consecutively on account of threatened abortion or premature labour and treated with Ritodrine and Verapamil intravenously in the usual dosage were investigated with respect to creatine kinase activity and, in the event of a raised level, its isoenzyme creatine kinase--MB. Determinations were carried out before treatment and, in accordance with expected peak values in case of myocardial necrosis, after 6 and 12 hours. Three pathological values were recorded and these are discussed individually. Furthermore, statistical evaluation of the recorded values showed no significant differences.


Asunto(s)
Cardiomiopatías/inducido químicamente , Trabajo de Parto Prematuro/prevención & control , Propanolaminas/efectos adversos , Ritodrina/efectos adversos , Verapamilo/administración & dosificación , Adolescente , Adulto , Creatina Quinasa/metabolismo , Femenino , Humanos , Isoenzimas , Embarazo
7.
Wien Klin Wochenschr ; 91(23): 798-801, 1979 Dec 07.
Artículo en Alemán | MEDLINE | ID: mdl-538935

RESUMEN

Fifty pregnant women admitted consecutively on account of threatened abortion or premature labour and treated with Ritodrine and Verapamil intravenously in the usual dosage were investigated with respect to creatine kinase activity and, in the event of a raised level, its isoenzyme creatine kinase--MB. Determinations were carried out before treatment and, in accordance with expected peak values in case of myocardial necrosis, after 6 and 12 hours. Three pathological values were recorded and these are discussed individually. Furthermore, statistical evaluation of the recorded values showed no significant differences.


Asunto(s)
Cardiomiopatías/inducido químicamente , Propanolaminas/efectos adversos , Ritodrina/efectos adversos , Verapamilo/efectos adversos , Amenaza de Aborto/tratamiento farmacológico , Adolescente , Adulto , Cardiomiopatías/enzimología , Cardiomiopatías/patología , Creatina Quinasa/metabolismo , Femenino , Humanos , Isoenzimas , Necrosis , Embarazo , Ritodrina/uso terapéutico , Verapamilo/uso terapéutico
8.
Wien Klin Wochenschr ; 92(14): 502-5, 1980 Jul 04.
Artículo en Alemán | MEDLINE | ID: mdl-6933741

RESUMEN

The serum myoglobin level was performed before as well as two and four hours following the beginning of intravenous tocolysis in 22 pregnant patients who were treated with the betasympathicomimetic agent, hexoprenalin because of premature labour. In six of the patients a rise of 26--140% in myoglobin was observed in comparison with the basal level. One of the patients even produced a twenty-fold rise. The value of serum myoglobin determination in the diagnosis of myocardial necroses is discussed with respect to the literature and the presented material.


Asunto(s)
Hexoprenalina/uso terapéutico , Mioglobina/análisis , Trabajo de Parto Prematuro/prevención & control , Fenetilaminas/uso terapéutico , Adulto , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Embarazo
9.
Wien Klin Wochenschr ; 99(21): 767-8, 1987 Nov 06.
Artículo en Alemán | MEDLINE | ID: mdl-3424845

RESUMEN

Radioactivity in human breast milk was determined in 32 women in February and March 1987 by means of a Germanium detector. At this time radioactivity increased again by feeding the hay to the cattle harvested in the weeks following the disaster of Chernobyl. 8 (25%) of the values were above 0.3 nCi/l for babies milk recommended by the local authorities.


Asunto(s)
Accidentes , Radioisótopos de Cesio/análisis , Leche Humana/efectos de la radiación , Reactores Nucleares , Centrales Eléctricas , Austria , Femenino , Humanos , Leche Humana/análisis , Ucrania
10.
Wien Klin Wochenschr ; 98(23): 803-5, 1986 Dec 05.
Artículo en Alemán | MEDLINE | ID: mdl-3811372

RESUMEN

Radioactivity was determined in the milk from 39 patients and in amniotic fluid, urine and placentas from 17 patients shortly after the Chernobyl disaster by means of a beta and gamma-scintillation counter. Elevated radioactivity (7.6 nCi/l beta activity and 7.4 nCi/l gamma activity) was found only in one sample of breast milk.


Asunto(s)
Accidentes , Intercambio Materno-Fetal/efectos de la radiación , Leche Humana/efectos de la radiación , Reactores Nucleares , Traumatismos por Radiación/prevención & control , Carga Corporal (Radioterapia) , Femenino , Humanos , Embarazo , Riesgo , Ucrania
11.
Wien Klin Wochenschr ; 100(18): 622-4, 1988 Sep 23.
Artículo en Alemán | MEDLINE | ID: mdl-3188538

RESUMEN

Chlorocarbons, which are used for cleaning purposes in both the home and industry, are of growing interest with respect to environmental pollution. We have therefore, compared the concentrations of chloroform (CH CL3), carbon tetrachloride (C CL4) and tetrachloroethylene (C2 CL4), determined by gas chromatography, in breast milk from 13 puerperal mothers from Innsbruck and the surrounding Tyrol with the respective data in 20 mothers from Linz and the surrounding industrial area. In fact, no elevation in chlorocarbon levels was detected in either group.


Asunto(s)
Hidrocarburos Clorados/análisis , Leche Humana/análisis , Austria , Tetracloruro de Carbono/análisis , Cloroformo/análisis , Cromatografía de Gases , Femenino , Humanos , Tetracloroetileno/análisis
12.
Wien Klin Wochenschr ; 103(3): 88-90, 1991.
Artículo en Alemán | MEDLINE | ID: mdl-1709314

RESUMEN

41 samples of human milk from the region of Tyrol were investigated with regard to benzo(a)pyrene content. A complicated analytical preparatory method had to be worked out. The percentage recovery of benzo(a)pyrene was 85-90. Analysis was carried out by means of capillary gas chromatography and flame ionization detection or mass spectrometry. The limit of benzo(a)pyrene detection is 0.1-1 microgram/kg (single ion monitoring). None of the investigated samples of milk showed the presence of benzo(a)pyrene.


Asunto(s)
Contaminantes Atmosféricos/análisis , Benzo(a)pireno/análisis , Polvo/análisis , Leche Humana/química , Emisiones de Vehículos/análisis , Austria , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos
13.
Wien Klin Wochenschr ; 109(22): 884-6, 1997 Nov 28.
Artículo en Alemán | MEDLINE | ID: mdl-9476337

RESUMEN

10 years after the Chernobyl disaster gamma radioactivity from Cs-137 was determined in 53 breast milk samples from Tyrol, as well as 9 samples from Tibet and 2 from Nepal by means of a gamma-spectrometer with a germanium detector. In contrast to the values obtained within a few days, and again 1 year after the nuclear plant catastrophe, all samples from Tyrol showed gamma radioactivity levels (median 0.07 nCi/l; range 0.02-0.20 nCi/l) which were now below the limit laid down for baby food in Austria (0.3 nCi/l-11.1 Bq). The samples from Tibet and Nepal registered a slightly higher level of gamma radioactivity (median 0.16 nCi/l; range 0.16-0.41 nCi/l).


Asunto(s)
Contaminación Radiactiva de Alimentos , Leche Humana/efectos de la radiación , Centrales Eléctricas , Liberación de Radiactividad Peligrosa , Radiactividad , Animales , Austria , Femenino , Rayos gamma , Humanos , Nepal , Reactores Nucleares , Tibet
14.
Wien Klin Wochenschr ; 105(24): 723-7, 1993.
Artículo en Alemán | MEDLINE | ID: mdl-8116310

RESUMEN

11 women gave birth to 13 live-born infants after a mean period of 39.6 months following transplantation, whereby one of these women had two successful pregnancies and one patient had a twin pregnancy. The highly premature twins, born after a complicated pregnancy with impaired renal graft function in the mother, died of respiratory insufficiency on the 13th day. All of these renal allograft recipients had to be delivered by caesarean section, either for nephrological or obstetric reasons. All graft with stable function prior to conception suffered no damage as a result of the pregnancy. In two women with already impaired function, pregnancy led to further deterioration and, eventually, graft loss. Because of the small numbers in this series no conclusions can be drawn with regard to the incidence of malformation of premature delivery. It is concluded that women with normal and stable renal graft function should be allowed to become pregnant. The risk for the graft as well as for the child does not seem to be increased under these circumstances. However, due to the complexity of the situation these patients should be cared for at specialized centres.


Asunto(s)
Trasplante de Riñón/fisiología , Complicaciones del Trabajo de Parto/fisiopatología , Complicaciones Posoperatorias/fisiopatología , Complicaciones del Embarazo/fisiopatología , Adulto , Cesárea , Femenino , Humanos , Inmunosupresores/administración & dosificación , Recién Nacido , Pruebas de Función Renal , Complicaciones del Trabajo de Parto/terapia , Grupo de Atención al Paciente , Complicaciones Posoperatorias/terapia , Embarazo , Complicaciones del Embarazo/terapia , Resultado del Embarazo , Embarazo Múltiple/fisiología
15.
Wien Klin Wochenschr ; 100(15): 519-22, 1988 Aug 05.
Artículo en Alemán | MEDLINE | ID: mdl-2459855

RESUMEN

The lead content of the milk of 28 breast feeding mothers from various regions in Tyrol was examined using flameless atomic absorption spectrometry. These examinations showed that the milk of women living in places with heavier traffic had a seven-fold higher lead level as compared with the data in women from regions with little traffic. This difference was statistically significant. We also determined the lead level of specimens of drinking water from 7 towns in Tyrol. The mean level was half the value found in maternal milk from women living in low-traffic regions.


Asunto(s)
Contaminación del Aire/análisis , Plomo/análisis , Leche Humana/análisis , Emisiones de Vehículos/análisis , Adulto , Austria , Femenino , Humanos
16.
Nat Commun ; 5: 3235, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24492681

RESUMEN

More than 40 years ago, Andreev, Lifshitz and Chester suggested the possible existence of a peculiar solid phase of matter, the microscopic constituents of which can flow superfluidly without resistance due to the formation of zero-point defects in the ground state of self-assembled crystals. Yet, a physical system where this mechanism is unambiguously established remains to be found, both experimentally and theoretically. Here we investigate the zero-temperature phase diagram of two-dimensional bosons with finite-range soft-core interactions. For low particle densities, the system is shown to feature a solid phase in which zero-point vacancies emerge spontaneously and give rise to superfluid flow of particles through the crystal. This provides the first example of defect-induced, continuous-space supersolidity consistent with the Andreev-Lifshitz-Chester scenario.

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