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1.
Eur J Cancer Care (Engl) ; 27(2): e12727, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28639355

RESUMEN

Diagnostic assessment programmes (DAPs) coordinate multidisciplinary teamwork (MDT), and improve wait times and patient satisfaction. No research has established optimal DAP design. This study explored how DAP characteristics influence service delivery. A mixed methods case study of four breast cancer DAPs was conducted including qualitative interviews with health-care providers and retrospective chart review. Data were integrated using multiple approaches. Twenty-three providers were interviewed; 411 medical records were reviewed. The number of visits and wait times from referral to diagnosis and consultation were lowest at a one-stop model. DAP characteristics (rural-remote region, human resources, referral volume, organisation of services, adherence to service delivery targets and one-stop model) may influence service delivery (number of visits, wait times). MDT, influenced by other DAP characteristics (co-location of staff, patient navigators, team functioning), may also influence service delivery. While the one-stop model may be ideal, all sites experienced similar and unique challenges. Further research is needed to understand how to optimise the organisation and delivery of DAP services. Measures reflecting individual, team and patient-reported outcomes should be used to assess the effectiveness and impact of DAPs in addition to more traditional measures such as wait times.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Atención a la Salud , Grupo de Atención al Paciente/organización & administración , Adulto , Anciano , Atención a la Salud/organización & administración , Atención a la Salud/normas , Femenino , Humanos , Persona de Mediana Edad , Satisfacción del Paciente , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Estudios Retrospectivos , Adulto Joven
2.
Phys Rev Lett ; 119(18): 182501, 2017 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-29219591

RESUMEN

We report the measurement of the beam-vector and tensor asymmetries A_{ed}^{V} and A_{d}^{T} in quasielastic (e[over →],e^{'}p) electrodisintegration of the deuteron at the MIT-Bates Linear Accelerator Center up to missing momentum of 500 MeV/c. Data were collected simultaneously over a momentum transfer range 0.1

3.
Clin Radiol ; 72(9): 796.e9-796.e17, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28495011

RESUMEN

AIM: To analyse and compare the computed tomography (CT) features of benign and malignant types of histopathologically proven cases of solitary fibrous tumours of pleura (SFTP). MATERIALS AND METHODS: Retrospective analysis of preoperative CT images of 28 cases of histopathologically proven and classified SFTP from three participating institutions was performed. Patient demographics and lesion characteristics including size, borders, presence of a pedicle, extension into the fissure, attenuation, enhancement, pleural effusion, and calcifications were recorded and correlated with the final histopathological diagnosis. Type and results of preoperative biopsy were also recorded. Follow-up imaging and the clinical charts were reviewed to identify recurrence. RESULTS: Out of 28 cases (15 women and 13 men), 18 were proven to be benign and 10 were malignant. The mean age of patients was 58.1±15.9 and 66.5±11.8 years (p=0.1564) for benign and malignant tumours, respectively. The median (interquartile range) diameter was 6.05 (3.2-10.9) cm for benign and 15.7 (7.1-17.5) cm for malignant type tumours (p=0.0291). Tumours had lobulate borders in 28% (5/18) of benign cases and in 80% (8/10) of malignant cases (p=0.0163). Extension into adjacent fissure was seen in 22% (4/18) of benign lesions and 40% (4/10) of malignant lesions (p=0.40). A pedicle was present in 17% (3/18) of benign and 10% (1/10) of malignant lesions (p=1). Heterogeneous attenuation was present in 61% (11/18) of benign and 90% (9/10) of malignant lesions (p=0.19). Calcification was present in 17% (3/18) of benign tumours and in 70% (7/10) of malignant tumours (p=0.0113). Pleural effusion was present in 6% (1/18) of benign and 40% (4/10) of malignant lesions (p=0.04). Only 1/13 preoperative fine-needle aspirates yielded diagnosis of SFTP. Preoperative diagnosis of SFTP was made in all cases (11/11) with core biopsies. At follow-up (1-10 years, mean 3 years), local recurrence occurred in 3/6 (50%) patients with malignant SFTP and in none of the 10 patients with benign SFTP. CONCLUSION: No definite imaging feature to differentiate benign from malignant SFTP was found. Large size, lobulate borders, presence of calcification, and ipsilateral pleural effusion were the only CT features predictive of malignancy. In suspected cases, core biopsies should be performed rather than fine-needle aspiration.


Asunto(s)
Tumor Fibroso Solitario Pleural/diagnóstico por imagen , Tumor Fibroso Solitario Pleural/patología , Tomografía Computarizada por Rayos X/métodos , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
4.
Rev Sci Instrum ; 94(1): 013101, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36725595

RESUMEN

Two extended x-ray absorption fine structure flat crystal x-ray spectrometers (EFX's) were designed and built for high-resolution x-ray spectroscopy over a large energy range with flexible, on-shot energy dispersion calibration capabilities. The EFX uses a flat silicon [111] crystal in the reflection geometry as the energy dispersive optic covering the energy range of 6.3-11.4 keV and achieving a spectral resolution of 4.5 eV with a source size of 50 µm at 7.2 keV. A shot-to-shot configurable calibration filter pack and Bayesian inference routine were used to constrain the energy dispersion relation to within ±3 eV. The EFX was primarily designed for x-ray absorption fine structure (XAFS) spectroscopy and provides significant improvement to the Laboratory for Laser Energetics' OMEGA-60 XAFS experimental platform. The EFX is capable of performing extended XAFS measurements of multiple absorption edges simultaneously on metal alloys and x-ray absorption near-edge spectroscopy to measure the electron structure of compressed 3d transition metals.

5.
Phys Rev Lett ; 107(25): 252501, 2011 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-22243068

RESUMEN

We report a precision measurement of the deuteron tensor analyzing powers T(20) and T(21) at the MIT-Bates Linear Accelerator Center. Data were collected simultaneously over a momentum transfer range Q=2.15-4.50 fm(-1) with the Bates Large Acceptance Spectrometer Toroid using a highly polarized deuterium internal gas target. The data are in excellent agreement with calculations in a framework of effective field theory. The deuteron charge monopole and quadrupole form factors G(C) and G(Q) were separated with improved precision, and the location of the first node of G(C) was confirmed at Q=4.19±0.05 fm(-1). The new data provide a strong constraint on theoretical models in a momentum transfer range covering the minimum of T(20) and the first node of G(C).

6.
Clin Radiol ; 66(7): 589-96, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21530954

RESUMEN

Systemic arterial air embolism is a rarely encountered but much feared complication of percutaneous lung biopsy. We present a comprehensive review of iatrogenic air embolism post-lung biopsy, a complication that is often suboptimally managed. This review was inspired by our own institutional experience and we use this to demonstrate that excellent outcomes from this complication can be seen with prompt treatment using hyperbaric oxygen chamber therapy, after initial patient stabilization has been achieved. Pathophysiology, clinical features, and risk factors are reviewed and misconceptions regards venous versus arterial air embolism are examined. An algorithm is provided for radiologists to ensure suspected patients are appropriately managed with more favourable outcomes.


Asunto(s)
Biopsia con Aguja/efectos adversos , Embolia Aérea/etiología , Pulmón/patología , Arterias , Embolia Aérea/diagnóstico por imagen , Embolia Aérea/terapia , Humanos , Oxigenoterapia Hiperbárica/métodos , Tomografía Computarizada por Rayos X/métodos
7.
Phys Rev Lett ; 105(21): 212502, 2010 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-21231294

RESUMEN

We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for x>1, which is sensitive to short-range contributions to the nuclear wave function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the "superfast" quarks probed at x>1. The falloff at x>1 is noticeably stronger in 2H and 3He, but nearly identical for all heavier nuclei.

8.
Phys Rev Lett ; 103(20): 202301, 2009 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-20365978

RESUMEN

New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from (2)H, (3)He, (4)He, (9)Be and (12)C for 0.3 < x < 0.9, Q(2) approximately 3-6 GeV(2). These data represent the first measurement of the EMC effect for (3)He at large x and a significant improvement for (4)He. The data do not support previous A-dependent or density-dependent fits to the EMC effect and suggest that the nuclear dependence of the quark distributions may depend on the local nuclear environment.

9.
Science ; 217(4554): 68-70, 1982 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-6806900

RESUMEN

alpha-Difluoromethylornithine is an enzyme-activated irreversible inhibitor of ornithine decarboxylase that forms a covalent bond with the enzyme. When alpha-[5-14C]difluoromethylornithine was administered to androgen-treated mice, only ornithine decarboxylase became labeled. Autoradiographic examination of kidney, liver, and brain indicated much more extensive incorporation of labeled difluoromethylornithine into kidney protein than into the protein of the other tissues. Such incorporation was greatly reduced by prior treatment of the mice with cycloheximide. These results correlate with the presence of ornithine decarboxylase activity which is much higher in the kidney than in the other tissues and is lost rapidly when protein synthesis is inhibited. The binding of this drug in vivo, therefore, is useful for determining the distribution of ornithine decarboxylase. The enzyme was predominantly located in the proximal tubule cells of the kidney in androgen-treated mice.


Asunto(s)
Carboxiliasas/metabolismo , Riñón/enzimología , Ornitina Descarboxilasa/metabolismo , Ornitina/análogos & derivados , Animales , Autorradiografía , Encéfalo/enzimología , Radioisótopos de Carbono , Eflornitina , Riñón/efectos de los fármacos , Hígado/enzimología , Ratones , Especificidad de Órganos , Ornitina/farmacología , Inhibidores de la Ornitina Descarboxilasa , Testosterona/farmacología
10.
Science ; 172(3984): 741-3, 1971 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-5572902

RESUMEN

High school students with 1 to 5 years' smoking experience have excessive cough, sputum production, and shortness of breath. When maximum expiratory flow is plotted against maximum expired volume, the curves of nonsmokers and smokers differ in shape. The smokers have lower flow rates at mid-vital capacity and at lower lung volumes. This probably reflects small airway obstruction in the smokers.


Asunto(s)
Adolescente , Pulmón/fisiopatología , Fumar/fisiopatología , Tos , Femenino , Humanos , Masculino , Moco , Pruebas de Función Respiratoria , Esputo , Capacidad Vital
11.
Science ; 194(4262): 329-30, 1976 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-823643

RESUMEN

Long-term administration of [D-Leu6, des-Gly-NH210, Pro-ethylamide9]-GnRH, an analog of gonadotropin releasing hormone, caused regression of neoplastic tissue in a rat bearing a spontaneous mammary adenocarcinoma and in rats in which tumors had been induced by treatment with dimethylbenzanthracene (DMBA). During two separate treatment periods with the analog, the tumor in the single animal regressed although it had previously grown spontaneously. After a third period of growth, ovariectomy also induced regression, suggesting endocrine dependency of the tumor. These observations were confirmed in the DMBA-induced tumor system, where tumor regression in the analog-treated rats was comparable to that observed in the ovariectomized rats, and in both cases the tumor regression was significant when compared to untreated controls.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormonas/uso terapéutico , Neoplasias Mamarias Experimentales/tratamiento farmacológico , 9,10-Dimetil-1,2-benzantraceno , Animales , Castración , Femenino , Hormona Liberadora de Gonadotropina/uso terapéutico , Ratas
12.
Can Respir J ; 15(1): 41-4, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18292853

RESUMEN

Fibrosing mediastinitis is a rare benign condition, which can cause compression of the pulmonary or systemic vessels, tracheobronchial tree, coronary arteries or esophagus, leading to disabling clinical symptoms and even death. The case of a 26-year-old woman who presented with dyspnea is described. She was found to have 80% stenosis of the right pulmonary artery secondary to fibrosing mediastinitis. The stenosis was managed successfully with an endovascular Palmaz-Schatz stent, and the patient remains symptom-free 10 years later.


Asunto(s)
Angioplastia de Balón , Fibrosis/complicaciones , Mediastinitis/complicaciones , Enfermedades Vasculares Periféricas/terapia , Arteria Pulmonar , Adulto , Constricción Patológica , Femenino , Humanos , Enfermedades Vasculares Periféricas/etiología , Stents , Resultado del Tratamiento
13.
Curr Oncol ; 25(Suppl 1): S115-S124, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29910654

RESUMEN

Although screening mammography has delivered many benefits since its introduction in Canada in 1988, questions about perceived harms warrant an up-to-date review. To help oncologists and physicians provide optimal patient recommendations, the literature was reviewed to find the latest guidelines for screening mammography, including benefits and perceived harms of overdiagnosis, false positives, false negatives, and technologic advances. For women 40-74 years of age who actually participate in screening every 1-2 years, breast cancer mortality is reduced by 40%. With appropriate corrections, overdiagnosis accounts for 10% or fewer breast cancers. False positives occur in about 10% of screened women, 80% of which are resolved with additional imaging, and 10%, with breast biopsy. An important limitation of screening is the false negatives (15%-20%). The technologic advances of digital breast tomosynthesis, breast ultrasonography, and magnetic resonance imaging counter the false negatives of screening mammography, particularly in women with dense breast tissue.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Detección Precoz del Cáncer , Biopsia , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Detección Precoz del Cáncer/historia , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/tendencias , Reacciones Falso Positivas , Femenino , Historia del Siglo XXI , Humanos , Imagen por Resonancia Magnética , Mamografía , Tamizaje Masivo/historia , Tamizaje Masivo/métodos , Tamizaje Masivo/tendencias , Oncología Médica/historia , Oncología Médica/métodos , Oncología Médica/tendencias , Ultrasonografía Mamaria
14.
Artículo en Inglés | MEDLINE | ID: mdl-31093030

RESUMEN

The properties of hot, dense plasmas generated by the irradiation of GaAs targets by the Titan laser at Lawrence Livermore National Laboratory were determined by the analysis of high resolution K shell spectra in the 9 keV to 11 keV range. The laser parameters, such as relatively long pulse duration and large focal spot, were chosen to produce a steady-state plasma with minimal edge gradients, and the time-integrated spectra were compared to non-LTE steady state spectrum simulations using the FLYCHK and NOMAD codes. The bulk plasma streaming velocity was measured from the energy shifts of the Ga He-like transitions and Li-like dielectronic satellites. The electron density and the electron energy distribution, both the thermal and the hot non-thermal components, were determined from the spectral line ratios. After accounting for the spectral line broadening contributions, the plasma turbulent motion was measured from the residual line widths. The ionization balance was determined from the ratios of the He-like through F-like spectral features. The detailed comparison of the experimental Ga spectrum and the spectrum simulated by the FLYCHK code indicates two significant discrepancies, the transition energy of a Li-like dielectronic satellite (designated t) and the calculated intensity of a He-like line (x), that should lead to improvements in the kinetics codes used to simulate the X-ray spectra from highly-charged ions.

15.
J Clin Invest ; 48(12): 2330-40, 1969 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-5355344

RESUMEN

Fractional reabsorption of water, sodium, and potassium at proximal and distal tubular sites within the nephron was studied by recollection-micropuncture experiments on dogs undergoing hypertonic mannitol diuresis. After an initial control hydropenic phase, 16% mannitol in modified Ringer's solution was administered intravenously, resulting in marked increases in fractional excretion of water (28.7%), sodium (12.6%), and potassium (63.9%). Inulin clearance decreased significantly from 35.1 to 25.2 ml/min. Analysis of paired micropuncture data revealed a significant decrease in tubule fluid to plasma (TF:P) inulin ratios in both the proximal tubule (1.63-1.45) and distal tubule (5.38-1.94). There was also a significant decrease in proximal TF:P sodium ratios (0.99-0.93) and potassium ratios (1.05-0.98). Distal TF:P sodium ratios, in contrast, rose significantly (0.38-0.59), while TF:P potassium ratios tended towards unity whether initially greater or less than one. Fractional reabsorption of sodium and water decreased by 5% and 10% respectively in the proximal tubule, but to a lesser extent than the resulting increases in fractional urinary excretion. The nonreabsorbed fraction, however, had increased sharply at the point of distal puncture for water (32%), sodium (26%), and potassium (26%), indicating a large inhibitory effect within the loop of Henle in addition to the smaller proximal effects.


Asunto(s)
Diuresis/efectos de los fármacos , Túbulos Renales/fisiología , Manitol/farmacología , Animales , Perros , Tasa de Filtración Glomerular , Soluciones Hipertónicas , Inulina/sangre , Inulina/metabolismo , Tasa de Depuración Metabólica , Potasio/sangre , Potasio/orina , Sodio/sangre , Sodio/orina , Agua/metabolismo , Equilibrio Hidroelectrolítico
16.
Acta Radiol ; 48(8): 838-45, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17851971

RESUMEN

BACKGROUND: While breast magnetic resonance imaging (MRI) is a highly sensitive test for detecting breast carcinoma, its specificity is lower, and several methods have been described on how to optimize specificity. PURPOSE: To compare the specificity and sensitivity of the BI-RADS category with the Fischer score in breast MRI for diagnosing cancer in women previously treated for breast cancer. MATERIAL AND METHODS: Women referred for evaluation of possible local recurrence or new breast cancer underwent breast MRI examination. Morphologic and kinetic enhancement characteristics were evaluated. BI-RADS category and Fischer score were assigned for each enhancing lesion and compared using a chi-square test. Sensitivity, specificity,and positive predictive values for 27 morphologic and enhancement characteristics were calculated. Pathologic diagnosis was obtained in all patients with enhancing lesions who had ultrasound or mammographic correlation. In those without correlate, 6-, 12-, and 24-month follow-up breast MRIs were obtained. Interobserver kappa correlation was determined for each variable studied. RESULTS: 34 benign and 32 malignant lesions were identified in 26 of 30 patients. BIRADS category yielded a specificity of 77.1% and a sensitivity of 81.8%. Fischer score had a lower specificity and sensitivity (62.9% and 72.7%, respectively) (P<0.0001). Of the 27 variables studied, >100% enhancement was more sensitive than BI-RADS for malignant lesions. Specificity was highest for rim enhancement (97.1%), but sensitivity was low (24.2%). Interobserver kappa correlation was good for all 27 characteristics(k=0.84), and highest for BI-RADS assessment (k=0.91). CONCLUSION: BI-RADS category in breast MRI had the highest combination of specificity and sensitivity, and the highest interobserver correlation. Fischer score and other morphologic and enhancement features lack sensitivity or specificity and do not have high positive predictive values when analyzed as single independent variables.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética/métodos , Recurrencia Local de Neoplasia/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Mama/anatomía & histología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Periodo Posoperatorio , Sensibilidad y Especificidad
17.
J Natl Cancer Inst ; 65(3): 577-83, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6931937

RESUMEN

A laboratory-bred and laboratory-reared male California king snake was submitted for clinical evaluation, and a mass was palpated caudal to the stomach and within the abdominal cavity. The snake was anesthetized and the mass was excised. A constricted atonic section of adjacent small intestine was removed and the ends were subsequently reanastomosed. The snake died 2 days post surgery; after histopathologic examination of all major organs (except muscle and brain), lymphosarcoma was diagnosed. Lymphocytes, approximately 70% of which contained small to large eosinophilic intranuclear inclusions, had infiltrated all major organs. By electron microscopic examination these inclusions were found to be large electron-dense granular structures. Aggregates of circular structures that measured 50 nm were seen in the cytoplasm of several cells.


Asunto(s)
Linfoma no Hodgkin/veterinaria , Serpientes , Neoplasias Abdominales/patología , Neoplasias Abdominales/veterinaria , Animales , Cuerpos de Inclusión Viral/ultraestructura , Intestino Delgado/patología , Riñón/patología , Hígado/patología , Pulmón/patología , Linfoma no Hodgkin/patología , Bazo/patología
18.
Cancer Res ; 60(13): 3461-9, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10910057

RESUMEN

Women who inherit mutations in the breast cancer susceptibility genes, BRCA1 and BRCA2, are predisposed to the development of breast and ovarian cancer. We used mice with a Brca1 mutation on a BALB/cJ inbred background (BALB/cB1+/- mice) or a Brca2 genetic alteration on the 129/SvEv genetic background (129B2+/- mice) to investigate potential gene-environment interactions between defects in these genes and treatment with the highly estrogenic compound diethylstilbestrol (DES). Beginning at 3 weeks of age, BALB/cB1+/-, 129B2+/-, and wild-type female mice were fed a control diet or a diet containing 640 ppb DES for 26 weeks. DES treatment caused vaginal epithelial hyperplasia and hyperkeratosis, uterine inflammation, adenomyosis, and fibrosis, as well as oviductal smooth muscle hypertrophy. The severity of the DES response was mouse strain specific. The estrogen-responsive 129/SvEv strain exhibited an extreme response in the reproductive tract, whereas the effect in BALB/cJ and C3H/HeN(MMTV-) mice was less severe. The Brca1 and Brca2 genetic alterations influenced the phenotypic response of BALB/cJ and 129/SvEv inbred strains, respectively, to DES in the mammary gland and ovary. The mammary duct branching morphology was inhibited in DES-treated BALB/cB1+/- mice compared with similarly treated BALB/cB1+/+ littermates. In addition, the majority of BALB/cB1+/- mice had atrophied ovaries, whereas wild-type littermates were largely diagnosed with arrested follicular development. The mammary ductal architecture in untreated 129B2+/- mice revealed a subtle inhibited branching phenotype that was enhanced with DES treatment. However, no significant differences were observed in ovarian pathology between 129B2+/+ and 129B2+/- mice. These data suggest that estrogenic compounds may modulate mammary gland or ovarian morphology in BALB/cB1+/- and 129B2+/- mice. These observations are consistent with the hypothesis that compromised DNA repair processes in cells harboring Brca1 or Brca2 mutations lead to inhibited growth and differentiation compared with the proliferative response of wild-type cells to DES treatment.


Asunto(s)
Dietilestilbestrol/toxicidad , Genes BRCA1/genética , Glándulas Mamarias Animales/patología , Proteínas de Neoplasias/genética , Ovario/patología , Factores de Transcripción/genética , Animales , Proteína BRCA2 , Carcinógenos/toxicidad , Quimera , Cruzamientos Genéticos , Endometriosis/patología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Trompas Uterinas/efectos de los fármacos , Trompas Uterinas/patología , Femenino , Fibrosis/inducido químicamente , Marcadores Genéticos , Heterocigoto , Hipertrofia , Inflamación , Glándulas Mamarias Animales/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Transgénicos , Músculo Liso/efectos de los fármacos , Músculo Liso/patología , Ovario/efectos de los fármacos , Fenotipo , Útero/efectos de los fármacos , Útero/patología , Vagina/efectos de los fármacos , Vagina/patología
19.
Rev Sci Instrum ; 87(11): 11E305, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910617

RESUMEN

A Cauchois transmission-crystal spectrometer has been developed with high crystal resolving power in the 6 keV-15 keV energy range and sufficient sensitivity to record single-shot spectra from the Lawrence Livermore National Laboratory (LLNL) Titan laser and other comparable or more energetic lasers. The spectrometer capabilities were tested by recording the W L transitions from a laboratory source and the extended x-ray absorption fine structure (EXAFS) spectrum through a Cu foil.

20.
Artículo en Inglés | MEDLINE | ID: mdl-31093029

RESUMEN

Experiments were performed at the LLNL Titan laser to measure the propagation direction of the energetic electrons that were generated during the interaction of the polarized laser beam with solid targets in the case of normal incidence. The energetic electrons propagated through vacuum to spectator metal wires in the polarization direction and in the perpendicular direction, and the K shell spectra from the different wire materials were recorded as functions of the distance from the laser focal spot. It was found that the fluence of the energetic electrons driven into the spectator wires in the polarization direction compared to the perpendicular direction was larger and increased with the distance from the focal spot. This indicates that energetic electrons are preferentially driven in the direction of the intense oscillating electric field of the incident laser beam in agreement with the multiphoton inverse Bremsstrahlung absorption process.

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