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1.
Phys Rev Lett ; 132(15): 150605, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682987

RESUMO

We demonstrate coherent control of the fine-structure qubit in neutral strontium atoms. This qubit is encoded in the metastable ^{3}P_{2} and ^{3}P_{0} states, coupled by a Raman transition. Using a magnetic quadrupole transition, we demonstrate coherent state initialization of this THz qubit. We show Rabi oscillations with more than 60 coherent cycles and single-qubit rotations on the µs scale. With spin echo, we demonstrate coherence times of tens of ms. Our results pave the way for fast quantum information processors and highly tunable quantum simulators with two-electron atoms.

2.
Phys Rev Lett ; 125(5): 053603, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32794877

RESUMO

Single particle-resolved fluorescence imaging is an enabling technology in cold-atom physics. However, so far, this technique has not been available for nanophotonic atom-light interfaces. Here, we image single atoms that are trapped and optically interfaced using an optical nanofiber. Near-resonant light is scattered off the atoms and imaged while counteracting heating mechanisms via degenerate Raman cooling. We detect trapped atoms within 150 ms and record image sequences of given atoms. Building on our technique, we perform two experiments which are conditioned on the number and position of the nanofiber-trapped atoms. We measure the transmission of nanofiber-guided resonant light and verify its exponential scaling in the few-atom limit, in accordance with Beer-Lambert's law. Moreover, depending on the interatomic distance, we observe interference of the fields that two simultaneously trapped atoms emit into the nanofiber. The demonstrated technique enables postselection and possible feedback schemes and thereby opens the road toward a new generation of experiments in quantum nanophotonics.

3.
J Eur Acad Dermatol Venereol ; 29(5): 919-24, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25258175

RESUMO

BACKGROUND: Acne is an important health issue with a major psychological impact in addition to the physical problems it causes. OBJECTIVES: To investigate the superiority of mobile teledermatology in the care of patients with high-need facial acne in comparison to outpatient services with particular attention to treatment efficacy, safety, and patient compliance. Further, patient satisfaction with remote care was evaluated. METHODS: Sixty-nine consecutive patients (f: 25, m: 44, median age: 19 years, range: 13-37 years) were randomly allocated to either the teleconsultation (TCA) or the outpatient consultation (OCA) arm of the trial to receive isotretinoin treatment in weight and severity-dependent dosages over 24 weeks. Acne grading was performed by one examiner using the Global Acne Severity Scale (GEA) and the total lesion counting (TLC). RESULTS: Due to noncompliance issues, 17 of 69 (24.6%) patients were excluded from the study, of who 10 had been assigned to the TCA (10/34; 29.4%) and 7 to the OCA (7/35; 20%). Both, in the TCA (GEA-score: ∆ = 2.25; TLC: ∆ = 89.08) and in the OCA (GEA-score: ∆ = 2.0; TLC: ∆ = 91.21) excellent and almost equivalent therapeutic outcomes were achieved. In the TCA, however, less patients experienced adverse reactions (P = 0.55). Even though additional live supervision would have been appreciated in some teledermatology cases, patients were satisfied with the mobile service and no consultation request was created. CONCLUSION: Mobile teledermatology is an efficient, safe and well-accepted tool among patients with high-need acne constituting at least a valuable adjunct to outpatient care services. Further larger studies would be useful to confirm our findings.


Assuntos
Acne Vulgar/tratamento farmacológico , Assistência Ambulatorial , Fármacos Dermatológicos/uso terapêutico , Dermatoses Faciais/tratamento farmacológico , Isotretinoína/uso terapêutico , Telemedicina , Adolescente , Adulto , Peso Corporal , Fármacos Dermatológicos/efeitos adversos , Feminino , Humanos , Isotretinoína/efeitos adversos , Masculino , Satisfação do Paciente , Índice de Gravidade de Doença , Adulto Jovem
4.
Eur J Gynaecol Oncol ; 27(5): 509-12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17139989

RESUMO

Primary malignant mixed Müllerian tumors (MMMTs) of the fallopian tube are rarities in gynecologic oncology with only 26 cases of MMMTs with a heterologous component reported thus far. We report a case of FIGO Stage II primary MMMT of the fallopian tube with a heterologous tumor portion in an 80-year-old woman presenting with abdominal discomfort at the time of primary diagnosis. After performance of total abdominal hysterectomy, bilateral salpingo-oophorectomy and omentectomy follow-up examination three months postoperatively did not show signs of disease recurrence. The patient finally presented six months after the initial diagnosis with extensive intraabdominal metastasis and died several days thereafter. The present report supports the aggressive nature of these neoplasms. The efficacy of chemotherapy and radiation remains to be defined in future studies.


Assuntos
Neoplasias das Tubas Uterinas/diagnóstico , Tumor Mulleriano Misto/diagnóstico , Idoso de 80 Anos ou mais , Neoplasias das Tubas Uterinas/cirurgia , Evolução Fatal , Feminino , Humanos , Tumor Mulleriano Misto/cirurgia , Recidiva Local de Neoplasia
5.
Biomaterials ; 15(8): 563-9, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7948574

RESUMO

Three different poly[(amino acid ester)phosphazenes] have been examined in order to investigate their possible use as drug delivery vehicles. The three polymers are poly[di(ethyl glycinato)phosphazene], poly[di(ethyl alanato)phosphazene] and poly[di(benzyl alanato)phosphazene]. These macromolecules either share the same amino acid residue or the same ester group, and this facilitated comparisons of the hydrolytic decomposition and the small molecule release profiles of the polymers. The polymers were synthesized by treatment of poly(dichlorophosphazene) with an excess of the appropriate amino acid ester. Tetrahydrofuran solutions of each polymer were then thoroughly mixed with ethacrynic acid, a diuretic, or Biebrich Scarlet, an azo dye. Films cast from these solutions were immersed in aqueous media (pH 7) at 25 degrees C and at 37 degrees C for approximately 1400 h. During these experiments, the release of the small molecules was monitored by UV/visible spectroscopy. The molecular weight decline and the mass loss of the polyphosphazene films were measured.


Assuntos
Aminoácidos/química , Preparações de Ação Retardada , Compostos Organofosforados/química , Polímeros/química , Biodegradação Ambiental , Ésteres , Ácido Etacrínico/química , Hidrólise , Compostos Organofosforados/síntese química , Tamanho da Partícula , Polímeros/síntese química , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade , Especificidade por Substrato
6.
Biomaterials ; 15(7): 502-6, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7918902

RESUMO

Urea amidohydrolase (urease) was immobilized within poly[di(methoxyethoxyethoxy)phosphazene] (MEEP) hydrogels. This was accomplished by mixing an aqueous solution (pH 7) of the soluble polymer with the enzyme. Films of the conjugate were cast and the solvent removed to yield an MEEP/enzyme composite. The conjugate films were dried in a vacuum and were then cross-linked by exposure to 0.2 or 0.5 Mrad of 60Co gamma-radiation to give an MEEP network with the enzyme entrapped within its matrix. The cross-linked films were sectioned into strips and were washed with pH 7 buffer to remove enzyme adhering to the surface. The films were then allowed to swell to form a hydrogel in pH 7 buffer to which was added a 1.0 M aqueous urea solution. The increase in pH from the conversion of urea to ammonia was monitored over a 24 h period. The immobilized enzyme could be recycled at least five times without significant loss of activity. Several control experiments were also performed by monitoring the pH of buffer solutions that contained hydrogels devoid of entrapped urease, and by monitoring the pH of solutions of the free, non-irradiated and free, irradiated urease after the addition of the urea solution. The polymer-free, irradiated urease lost little to no activity compared with its non-irradiated counterpart. The MEEP gel-immobilized enzyme retained approximately 80% of the activity of the non-irradiated, polymer-free urease.


Assuntos
Enzimas Imobilizadas/metabolismo , Compostos Organofosforados/química , Polímeros/química , Urease/metabolismo , Reagentes de Ligações Cruzadas , Enzimas Imobilizadas/química , Raios gama , Géis , Concentração de Íons de Hidrogênio , Compostos Organofosforados/síntese química , Polímeros/síntese química , Urease/química
7.
J Biomed Mater Res ; 27(7): 963-73, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8360223

RESUMO

The hydrolytically unstable polyphosphazenes, poly [(imidazolyl) (methylphenoxy) phosphazenes] and poly [ethyl glycinato) (methylphenoxy) phosphazenes], were studied as potential polymeric supports for cells in tissue regeneration. For bone repair, their specific function would be to support osteoblast growth, forming a bone-polymer matrix. MC3T3-E1 cells (an osteogenic cell line) were seeded onto polymer matrices and cell adhesion and growth as well as polymer degradation were examined. Both imidazolyl- and ethyl glycinato-substituted polyphosphazenes supported the growth of MC3T3-E1 cells. An increase in the content of the imidazolyl side group resulted in a reduction in cell attachment and growth on the polymer surface and an increase in the rate of degradation of the polymer. In contrast, substitution with the ethyl glycinato group favored increased cell adhesion and growth and also an increase in the rate of degradation of the polymers. Thus, the polyphosphazenes represent a system whereby cell growth and degradation can be modulated by varying the nature of the hydrolytically unstable side chain. This in vitro evaluation suggests that the polyphosphazenes may be suitable candidate biomaterials for the construction of a cell-polymer matrix for tissue regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Compostos Organofosforados/farmacologia , Polímeros/farmacologia , Animais , Adesão Celular , Divisão Celular , Linhagem Celular , Camundongos
8.
Biomaterials ; 13(12): 857-62, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1457679

RESUMO

Eight water-soluble phosphazene high polymers, [NPR2]n (R, organic, water-solubilizing side-group; n, approx: 15,000) and the small-molecule counterparts of the polymers were examined for antibacterial activity against six different strains of bacteria (Escherichia coli, Salmonella typhimurium (TA 100), Salmonella pullorum, Streptococcus faecalis, Bacillus subtilis and Pseudomonas aeruginosa). Antibacterial testing was carried out by measuring zones of inhibition and changes in solution turbidity over time. In addition, the antibacterial activity of the surfaces of cross-linked poly[di(methoxyethoxyethoxy)phosphazene] (MEEP) hydrogels were investigated. A number of the high polymers, as well as the MEEP hydrogels, impeded bacterial growth. Only E. coli was unaffected by the phosphazenes. A possible explanation for the antibacterial character of the polymers is presented. The same compounds were monitored for potential mutagenic activity using the Salmonella typhimurium tester strains TA 100 and TA 98. None of the high polymers or their small-molecule analogues showed mutagenic activity in either strain of Salmonella at the concentrations tested. The use of these materials as coatings for artificial implants is discussed.


Assuntos
Antibacterianos/farmacologia , Aziridinas/farmacologia , Bactérias/efeitos dos fármacos , Mutagênicos , Bacillus subtilis/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peso Molecular , Testes de Mutagenicidade , Polímeros , Pseudomonas aeruginosa/efeitos dos fármacos , Solubilidade
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