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1.
Phys Rev Lett ; 126(15): 153401, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929220

RESUMO

We prepare mixtures of ultracold CaF molecules and Rb atoms in a magnetic trap and study their inelastic collisions. When the atoms are prepared in the spin-stretched state and the molecules in the spin-stretched component of the first rotationally excited state, they collide inelastically with a rate coefficient k_{2}=(6.6±1.5)×10^{-11} cm^{3}/s at temperatures near 100 µK. We attribute this to rotation-changing collisions. When the molecules are in the ground rotational state we see no inelastic loss and set an upper bound on the spin-relaxation rate coefficient of k_{2}<5.8×10^{-12} cm^{3}/s with 95% confidence. We compare these measurements to the results of a single-channel loss model based on quantum defect theory. The comparison suggests a short-range loss parameter close to unity for rotationally excited molecules, but below 0.04 for molecules in the rotational ground state.

2.
Acta Diabetol ; 57(10): 1245-1253, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32488499

RESUMO

AIMS: To compare diabetes patients with hyperglycaemic hyperosmolar state (HHS), diabetic ketoacidosis (DKA), and patients without decompensation (ND). METHODS: In total, 500,973 patients with type 1 or type 2 diabetes of all ages registered in the diabetes patient follow-up (DPV) were included. Analysis was stratified by age (≤ / > 20 years) and by manifestation/follow-up. Patients were categorized into three groups: HHS or DKA-during follow-up according to the most recent episode-or ND. RESULTS: At onset of diabetes, HHS criteria were met by 345 (68.4% T1D) and DKA by 9824 (97.6% T1D) patients. DKA patients had a lower BMI(-SDS) in both diabetes types compared to ND. HbA1c was higher in HHS/DKA. During follow-up, HHS occurred in 1451 (42.2% T1D) and DKA in 8389 patients (76.7% T1D). In paediatric T1D, HHS/DKA was associated with younger age, depression, and dyslipidemia. Pump usage was less frequent in DKA patients. In adult T1D/T2D subjects, metabolic control was worse in patients with HHS/DKA. HHS and DKA were also associated with excessive alcohol intake, dementia, stroke, chronic kidney disease, and depression. CONCLUSIONS: HHS/DKA occurred mostly in T1D and younger patients. However, both also occurred in T2D, which is of great importance in the treatment of diabetes. Better education programmes are necessary to prevent decompensation and comorbidities.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Cetoacidose Diabética/epidemiologia , Hiperglicemia/epidemiologia , Coma Hiperglicêmico Hiperosmolar não Cetótico/epidemiologia , Adolescente , Adulto , Idoso , Áustria/epidemiologia , Criança , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Cetoacidose Diabética/sangue , Cetoacidose Diabética/complicações , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Hiperglicemia/sangue , Hiperglicemia/complicações , Coma Hiperglicêmico Hiperosmolar não Cetótico/sangue , Coma Hiperglicêmico Hiperosmolar não Cetótico/complicações , Luxemburgo/epidemiologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Suíça/epidemiologia , Adulto Jovem
3.
Phys Rev Lett ; 124(6): 063001, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109098

RESUMO

Polar molecules in superpositions of rotational states exhibit long-range dipolar interactions, but maintaining their coherence in a trapped sample is a challenge. We present calculations that show many laser-coolable molecules have convenient rotational transitions that are exceptionally insensitive to magnetic fields. We verify this experimentally for CaF where we find a transition with sensitivity below 5 Hz G^{-1} and use it to demonstrate a rotational coherence time of 6.4(8) ms in a magnetic trap. Simulations suggest it is feasible to extend this to more than 1 s using a smaller cloud in a biased magnetic trap.

4.
Phys Rev Lett ; 123(3): 033202, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31386461

RESUMO

We introduce a scheme for deep laser cooling of molecules based on robust dark states at zero velocity. By simulating this scheme, we show it to be a widely applicable method that can reach the recoil limit or below. We demonstrate and characterize the method experimentally, reaching a temperature of 5.4(7) µK. We solve a general problem of measuring low temperatures for large clouds by rotating the phase-space distribution and then directly imaging the complete velocity distribution. Using the same phase-space rotation method, we rapidly compress the cloud. Applying the cooling method a second time, we compress both the position and velocity distributions.

5.
Phys Rev Lett ; 120(16): 163201, 2018 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-29756945

RESUMO

We demonstrate coherent microwave control of the rotational, hyperfine, and Zeeman states of ultracold CaF molecules, and the magnetic trapping of these molecules in a single, selectable quantum state. We trap about 5×10^{3} molecules for almost 2 s at a temperature of 70(8) µK and a density of 1.2×10^{5} cm^{-3}. We measure the state-specific loss rate due to collisions with background helium.

6.
Phys Rev Lett ; 120(12): 123201, 2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29694100

RESUMO

We demonstrate one-dimensional sub-Doppler laser cooling of a beam of YbF molecules to 100 µK. This is a key step towards a measurement of the electron's electric dipole moment using ultracold molecules. We compare the effectiveness of magnetically assisted and polarization-gradient sub-Doppler cooling mechanisms. We model the experiment and find good agreement with our data.

7.
Phys Rev Lett ; 120(8): 083201, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29543030

RESUMO

We present the properties and advantages of a new magneto-optical trap (MOT) where blue-detuned light drives "type-II" transitions that have dark ground states. Using ^{87}Rb, we reach a radiation-pressure-limited density exceeding 10^{11} cm^{-3} and a temperature below 30 µK. The phase-space density is higher than in normal atomic MOTs and a million times higher than comparable red-detuned type-II MOTs, making the blue-detuned MOT particularly attractive for molecular MOTs, which rely on type-II transitions. The loss of atoms from the trap is dominated by ultracold collisions between Rb atoms. For typical trapping conditions, we measure a loss rate of 1.8(4)×10^{-10} cm^{3} s^{-1}.

8.
Appl Clin Inform ; 9(1): 122-128, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29466818

RESUMO

BACKGROUND: Identifying pneumonia using diagnosis codes alone may be insufficient for research on clinical decision making. Natural language processing (NLP) may enable the inclusion of cases missed by diagnosis codes. OBJECTIVES: This article (1) develops a NLP tool that identifies the clinical assertion of pneumonia from physician emergency department (ED) notes, and (2) compares classification methods using diagnosis codes versus NLP against a gold standard of manual chart review to identify patients initially treated for pneumonia. METHODS: Among a national population of ED visits occurring between 2006 and 2012 across the Veterans Affairs health system, we extracted 811 physician documents containing search terms for pneumonia for training, and 100 random documents for validation. Two reviewers annotated span- and document-level classifications of the clinical assertion of pneumonia. An NLP tool using a support vector machine was trained on the enriched documents. We extracted diagnosis codes assigned in the ED and upon hospital discharge and calculated performance characteristics for diagnosis codes, NLP, and NLP plus diagnosis codes against manual review in training and validation sets. RESULTS: Among the training documents, 51% contained clinical assertions of pneumonia; in the validation set, 9% were classified with pneumonia, of which 100% contained pneumonia search terms. After enriching with search terms, the NLP system alone demonstrated a recall/sensitivity of 0.72 (training) and 0.55 (validation), and a precision/positive predictive value (PPV) of 0.89 (training) and 0.71 (validation). ED-assigned diagnostic codes demonstrated lower recall/sensitivity (0.48 and 0.44) but higher precision/PPV (0.95 in training, 1.0 in validation); the NLP system identified more "possible-treated" cases than diagnostic coding. An approach combining NLP and ED-assigned diagnostic coding classification achieved the best performance (sensitivity 0.89 and PPV 0.80). CONCLUSION: System-wide application of NLP to clinical text can increase capture of initial diagnostic hypotheses, an important inclusion when studying diagnosis and clinical decision-making under uncertainty.


Assuntos
Serviço Hospitalar de Emergência , Processamento de Linguagem Natural , Pneumonia/diagnóstico , Pneumonia/terapia , United States Department of Veterans Affairs , Estudos de Coortes , Humanos , Curva ROC , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Estados Unidos
9.
Eur J Med Chem ; 127: 22-40, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28038325

RESUMO

Malaria is one of the most significant tropical diseases and remains a major challenge due to the lack of a broadly effective vaccine and parasite resistance to current drugs. This means there is a need for new drug candidates with novel modes of action. Aromatic bisamidines, such as furamidine (DB75), were initially developed as anti-Trypanosoma agents however as clinical trials with furamidine highlighted potential side effects they were not pursued further in that setting. Despite apparent cytotoxicity liabilities the potency of furamidine against Plasmodium falciparum makes it a promising scaffold for the development of new anti-Plasmodium agents with improved selectivity. In this study a bisamidine compound series based on furamidine was synthesized by introducing modifications at the furan core structure and terminal amidine groups. The activity of the derived compounds was tested in vitro against drug sensitive and resistant P. falciparum lines and a human cell line (HEK293 cells) to generate anti-Plasmodium structure-activity relationships and to provide preliminary selectivity data.


Assuntos
Antimaláricos/síntese química , Antimaláricos/farmacologia , Furanos/síntese química , Furanos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/química , Antimaláricos/toxicidade , Células CACO-2 , Técnicas de Química Sintética , Desenho de Fármacos , Furanos/química , Furanos/toxicidade , Células HEK293 , Humanos , Relação Estrutura-Atividade
10.
Rev Sci Instrum ; 87(11): 115110, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910460

RESUMO

We describe a parallel pair of high voltage electric field plates designed and constructed to minimise magnetic Johnson noise. They are formed by laminating glass substrates with a commercially available polyimide (Kapton) tape, covered with a thin gold film. Tested in vacuum, the outgassing rate is less than 5 × 10-5 mbar l/s. The plates have been operated at electric fields up to 8.3 kV/cm, when the leakage current is at most a few hundred pA. The design is discussed in the context of a molecular spin precession experiment to measure the permanent electric dipole moment of the electron.

11.
Cancer Radiother ; 18(1): 55-8, 2014 Jan.
Artigo em Francês | MEDLINE | ID: mdl-24315043

RESUMO

Gastro-intestinal stromal tumours are the most common mesenchymal neoplasms of the gastrointestinal tract. Their usual metastatic sites are the liver and the peritoneum, but gastro-intestinal stromal tumours rarely metastasize to the bones. We report the case of a 56-year-old male presenting with bone lesions six years after initial surgical resection. We discuss through this paper the possibilities of management of these lesions and the place of radiotherapy.


Assuntos
Neoplasias Ósseas/secundário , Tumores do Estroma Gastrointestinal/secundário , Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Neoplasias Ósseas/radioterapia , Neoplasias Femorais/tratamento farmacológico , Neoplasias Femorais/radioterapia , Neoplasias Femorais/secundário , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/terapia , Hepatectomia , Humanos , Úmero/patologia , Mesilato de Imatinib , Ísquio/patologia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Osteólise/etiologia , Manejo da Dor , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/secundário , Piperazinas/uso terapêutico , Osso Púbico/patologia , Pirimidinas/uso terapêutico , Neoplasias Gástricas/cirurgia
12.
Phys Chem Chem Phys ; 15(29): 12299-307, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23775176

RESUMO

We present a combined experimental and theoretical study of beam formation from a cryogenic buffer gas cell. Atoms and molecules are loaded into the cell by laser ablation of a target, and are cooled and swept out of the cell by a flow of cold helium. We study the thermalization and flow dynamics inside the cell and measure how the speed, temperature, divergence and extraction efficiency of the beam are influenced by the helium flow. We use a finite element model to simulate the flow dynamics and use the predictions of this model to interpret our experimental results.

13.
Dtsch Med Wochenschr ; 137(8): 368-70, 2012 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-22334362

RESUMO

HISTORY AND ADMISSION FINDINGS: A 58-year-old man was admitted for elucidation of a microcytic anemia diagnosed by his general practitioner (hemoglobin of 5,5 g/dl). He felt dizzy and unwell. The patient had for some time been regularly taking 1-2 tablets of diclofenac, a nonsteroid anti-inflammatory drug (NSAID), for joint and gouty pain. He had occasionally noted small amounts of blood on his stool. The physical examination was unremarkable except for obesity, several swollen and painful joints, and a gouty right big toe with a tophus and small ulcer. INVESTIGATIONS: Coloscopy revealed extensive multiple aphthous ulcers throughout the colon (histologically diagnosed as NSAID colopathy). Esophagogastroduodenoscopy failed to identify a source of bleeding. But it also revealed a double pylorus, which was divided into two equal parts by a smooth, pencil-thick circular band, but fully patent and without inflammatory changes or scarring. TREATMENT AND COURSE: Several erythrocyte units were infused, which stabilized the patient's condition. There was no evidence of renewed bleeding. But subsequently he experienced severe joint pain, the CPR rising to 252.31 mg/dl. Administration of steroids, novaminsulfon and opioids, as well as uric acid lowering drugs gradually improved the joint pain and enabled physiotherapy to improve mobility and the patient was discharged home. CONCLUSION: Congenital abnormalities are rarely found during gastrointestinal endoscopy in adults. Very rare are duplications of the pyloric channel most of which are acquired by ulcer perforation. In general, congenital double pylorus is mainly a harmless incidental finding which needs no therapy, but it should be distinguished from acquired double pylorus. Endoscopists should be aware of this abnormality to avoid complications during side-view endoscopy.


Assuntos
Endoscopia Gastrointestinal/métodos , Piloro/anormalidades , Piloro/patologia , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade
14.
J Nanosci Nanotechnol ; 11(9): 7994-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22097518

RESUMO

We show that Al2O3 thin films, grown by atomic layer deposition (ALD) on polyester, are ultrabarriers with moisture permeation <10(-5) g-H2O/m2-day, as determined after aging for more than three years. We present evidence that the mechanism for gas permeation in ALD Al2O3 films is not due to pinholes, but that the onset of permeation occurs abruptly, analogous to electrical breakdown in oxide thin films. We show that the permeation onset time increases for thicker Al2O3 films and higher ALD process temperature, for which the hydrogen defect concentration in Al2O3 films is less. Further, we show that mild plasma treatment of the polyester, prior to ALD deposition of Al2O3, makes the surface more hydrophilic and reduces moisture permeation compared to an untreated surface. Similarly, ALD deposition on the bare or non-slip side of the polyester film is preferred for low permeation.

15.
Phys Chem Chem Phys ; 13(42): 19013-7, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21822518

RESUMO

The fluorescence spectrum resulting from laser excitation of the A(2)Π(1/2)←X(2)Σ(+) (0,0) band of ytterbium monofluoride, YbF, has been recorded and analyzed to determine the Franck-Condon factors. The measured values are compared with those predicted from Rydberg-Klein-Rees (RKR) potential energy curves. From the fluorescence decay curve the radiative lifetime of the A(2)Π(1/2) state is measured to be 28 ± 2 ns, and the corresponding transition dipole moment is 4.39 ± 0.16 D. The implications for laser cooling YbF are discussed.

16.
Phys Chem Chem Phys ; 13(42): 18991-9, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21776450

RESUMO

We report the Stark deceleration of CaF molecules in the strong-field seeking ground state and in a weak-field seeking component of a rotationally-excited state. We use two types of decelerator, a conventional Stark decelerator for the weak-field seekers and an alternating gradient decelerator for the strong-field seekers, and we compare their relative merits. We also consider the application of laser cooling to increase the phase-space density of decelerated molecules.

17.
Nature ; 473(7348): 493-6, 2011 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-21614077

RESUMO

The electron is predicted to be slightly aspheric, with a distortion characterized by the electric dipole moment (EDM), d(e). No experiment has ever detected this deviation. The standard model of particle physics predicts that d(e) is far too small to detect, being some eleven orders of magnitude smaller than the current experimental sensitivity. However, many extensions to the standard model naturally predict much larger values of d(e) that should be detectable. This makes the search for the electron EDM a powerful way to search for new physics and constrain the possible extensions. In particular, the popular idea that new supersymmetric particles may exist at masses of a few hundred GeV/c(2) (where c is the speed of light) is difficult to reconcile with the absence of an electron EDM at the present limit of sensitivity. The size of the EDM is also intimately related to the question of why the Universe has so little antimatter. If the reason is that some undiscovered particle interaction breaks the symmetry between matter and antimatter, this should result in a measurable EDM in most models of particle physics. Here we use cold polar molecules to measure the electron EDM at the highest level of precision reported so far, providing a constraint on any possible new interactions. We obtain d(e) = (-2.4 ± 5.7(stat) ± 1.5(syst)) × 10(-28)e cm, where e is the charge on the electron, which sets a new upper limit of |d(e)| < 10.5 × 10(-28)e cm with 90 per cent confidence. This result, consistent with zero, indicates that the electron is spherical at this improved level of precision. Our measurement of atto-electronvolt energy shifts in a molecule probes new physics at the tera-electronvolt energy scale.

18.
Endoscopy ; 43(6): 512-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21618151

RESUMO

BACKGROUND: Biliary leaks and strictures are common complications after liver transplantation and can be managed surgically or endoscopically. Endoscopic management using fully covered self-expandable metal stents (FCSEMS) might provide some advantages over the commonly used plastic stents in the management of bile leaks after liver transplantation. METHODS: Between December 2006 and January 2009, 17 liver transplant recipients underwent placement of a FCSEMS for treatment of biliary leaks. RESULTS: FCSEMS were deployed at median of 18 days (range: 6 - 160) after liver transplantation and left in place for a median of 102 days (range: 35 - 427), with a median follow-up after FCSEMS removal of 407 days (range: 27 - 972). Long-term leak control was obtained in all but one patient. Complications included 6 clinically significant biliary strictures (35 %), which were treated with repeat stent placement, and two clinically insignificant strictures (12 %) which required no intervention. Additionally, three patients (18 %) had biliary ulcerations after stent removal, confirmed by choledochoscopy, and were managed conservatively. Two patients required repeat liver transplantation due to hepatic artery thrombosis, and one patient died from sepsis unrelated to FCSEMS stenting. CONCLUSIONS: FCSEMS treat biliary leaks effectively, but carry a relatively high stricture risk in patients who have received liver transplants. FCSEMS cannot be recommended for management of biliary leaks following liver transplantation at this point.


Assuntos
Doenças dos Ductos Biliares/etiologia , Ductos Biliares/cirurgia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Stents/efeitos adversos , Adulto , Anastomose Cirúrgica , Doenças dos Ductos Biliares/cirurgia , Colangiopancreatografia Retrógrada Endoscópica , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Desenho de Prótese
20.
Z Gastroenterol ; 47(8): 749-52, 2009 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-19662587

RESUMO

Fistulas into the large vessels are a rare cause of intestinal bleeding. In some cases they are caused by transmural perforation after the accidental swallowing of a sharp foreign body like a bone or a fish bone. We report about a 79-year-old patient who had swallowed a fragment of a wooden meat skewer which induced a perforation of the oesophagus and aorta walls. The patient was admitted to the hospital with signs of severe gastrointestinal bleeding. The emergency endoscopic examination confirmed the cause of the bleeding, but the patient died during the intervention from haemorrhagic shock. The forensic autopsy confirmed the clinical suspicion of an aorto-oesophageal fistula.


Assuntos
Aorta/lesões , Deglutição , Esôfago/lesões , Corpos Estranhos/complicações , Hemorragia Gastrointestinal/etiologia , Ferimentos Penetrantes/etiologia , Administração Oral , Idoso , Evolução Fatal , Corpos Estranhos/etiologia , Humanos , Masculino , Madeira , Ferimentos Penetrantes/diagnóstico
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