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1.
Rev Sci Instrum ; 91(8): 085116, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32872934

RESUMEN

We present a method to stabilize two lasers to an optical cavity using pulsed triple frequency modulation. The setup allows simultaneous Pound-Drever-Hall stabilization, as well as independent frequency control, while removing interference terms that limit the frequency scan range and allowing for smaller modulation depths. A review of single, dual, and triple frequency modulation is also presented in addition to a discussion of how to effectively turn pulsed triple frequency modulation into independent dual frequency modulation for each laser. This method would increase the scan range to half the free spectral range.

2.
Phys Rev Lett ; 121(5): 053001, 2018 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-30118286

RESUMEN

We report spectroscopic results on the 2s2p^{1}P_{1} state in neutral atomic beryllium-9. The absolute frequency for the center of gravity is determined to be 42 565.4501(13) cm^{-1}, a factor of 130 more precise than the previous experimental measurement. The result is in agreement with and a factor of 8 more precise than the current best theoretical estimate of 42 565.441(11) cm^{-1}, which was calculated including the effects of quantum electrodynamics. Because of the large natural linewidth of the transition, the hyperfine constants were not able to be extracted to high precision.

3.
Rev Sci Instrum ; 89(3): 033107, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29604741

RESUMEN

We report on the calibration of a temperature stabilized ultra-low expansion (ULE) cavity using previously measured molecular tellurium and atomic cesium lines. By means of a dual frequency modulation technique, the frequency dependence of the free spectral range of the ULE cavity is measured and was found to vary by less than 60 Hz over the ∼55 THz range of the calibration. This method of calibration enables the ULE cavity to measure absolute frequencies to better than 1.5 MHz.

5.
Ing. sanit. ambient ; 57: 64-8, Jul.-ago. 2001. ilus, tab
Artículo en Español | BINACIS | ID: biblio-1162932
6.
Water Sci Technol ; 43(4): 85-91, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11379231

RESUMEN

The global hydrological and salt cycles are described, as are the ways in which human activities have led to their disturbance. One effect of this disturbance is the unnatural increase in the salinity of many inland waters (secondary salinization). The geographical extent of secondary salinization is outlined, together with its effects on various types of inland waters, such as salt lakes, freshwater lakes and wetlands, and rivers and streams. The likely impact on salinization of global climate change is summarized.


Asunto(s)
Desastres , Agua Dulce , Sales (Química) , Abastecimiento de Agua , Salud Global , Humanos
7.
Appl Opt ; 37(12): 2334-9, 1998 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-18273160

RESUMEN

Two-line fluorescence thermometry measurements based on excitation of the A-X (0, 0) band of nitric oxide were performed in the free-stream flow of a large-scale shock tunnel, the Arnold Engineering Development Center Impulse Facility. Because the flow is optically thick, effects of laser absorption must be taken into account. This can be accomplished by extending the two-line thermometry concept to three lines. We illustrate the three-line technique by combining two-line planar laser-induced fluorescence measurements from separate facility runs. The resulting free-stream temperature T(0) = 468 K ? 65 K is insensitive to assumptions regarding the laser propagation distance through the flow, the vibrational temperature of the flow, and the precise nature of the absorption line shape.

8.
Am J Med ; 94(3): 289-95, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8452153

RESUMEN

PURPOSE: Priapism is an uncommon but debilitating complication of sickle cell disease (SCD). Recent observations among adult males regarding the abysmal failure of medical and surgical therapy encouraged us to review our 25-year experience identifying the prognostic features that might determine outcome. PATIENTS AND METHODS: As part of a prospective 25-year longitudinal demographic and clinical cohort study, a subset of 38 (8.2%) patients with priapism were identified among a cohort of 461 men with SCD. The patients with priapism were compared with the nonaffected men with respect to severity of disease expression, hematologic status, beta s globin gene haplotype, and the incidence of sickle-related major organ failure. The influence of the treatment modalities on outcome was also evaluated. RESULTS: Priapism occurred as a single episode in 24 patients, and in 14 as temporally clustered repeat episodes. Eighty-seven percent of those with priapism had sickle cell anemia (SS), an increased risk as compared with other variants of SCD (p = < 0.05). There were two distinct age-related patterns of disease expression. Eight patients were prepubertal; they experienced shorter episodes, involvement of the corpora cavernosa only, few recurrent episodes, and a good prognosis for future erectile function. Non-surgical therapy in children was associated with excellent results. In contrast, the 29 postpubertal adults often had involvement of the corpora cavernosa and corpus spongiosa (tricorporal disease) and half had prolonged episodes that lasted longer than 8 days. One pubescent patient had repeated episodes and became impotent. Prolonged or repeated episodes eventuated in impotence in 56%. Surgical intervention was not beneficial. Sickle cell-related organ failure such as stroke, chronic restrictive lung disease, chronic renal failure, and nonhealing leg ulcers was observed more frequently in men who had priapism. Death occurred in nine adult patients (25%) within 5 years of the first episode of priapism. CONCLUSION: Priapism in adult males identifies those at high risk for other sickle cell-related organ failure syndromes and, as such, is another complication indicative of severe disease. The dismal prognosis in SS adults requires better understanding of the precise pathophysiology of low-flow tricorporal priapism. Clarification of the mechanisms inducing the priapic state should lead to specific therapeutic maneuvers and an improved prognosis for this disabling condition.


Asunto(s)
Anemia de Células Falciformes/complicaciones , Enfermedad de la Hemoglobina SC/complicaciones , Priapismo/etiología , Talasemia beta/complicaciones , Adolescente , Adulto , Factores de Edad , Anemia de Células Falciformes/genética , Niño , Preescolar , Estudios de Cohortes , Enfermedad de la Hemoglobina SC/genética , Humanos , Estudios Longitudinales , Masculino , Priapismo/epidemiología , Priapismo/genética , Estudios Prospectivos , Factores de Riesgo
9.
Ann Surg ; 216(4): 446-52; discussion 453, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1417194

RESUMEN

Successful genetic transduction of endothelial cells (EC) provides a theoretic means of increasing luminal secretion of tissue-type plasminogen activator (tPA) and lessening arterial and venous thrombotic processes. To identify the duration and number of retroviral exposures for an optimal tPA expression, enzymatically derived adult canine jugular venous EC were subjected to different exposure regimens using an amphotropic murine retroviral vector, MFG, containing the human tPA gene. Human tPA antigen secretion and its functional activity were determined at 2 days (subconfluent cells) and 14 days (confluent cells) after retroviral exposure. High-level secretion of human tPA was detected among transduced EC in all experimental groups. No secretion of human tPA occurred in control EC exposed to media alone. At 2 days after transduction, no significant differences in tPA secretion rates occurred among the different exposure regimens. At 14 days, the 12-hour X two-exposure group exhibited higher tPA secretion rates than all other exposure regimens (analysis of variance, p < 0.05). All exposure groups at 14 days exhibited significantly higher tPA secretion compared with those at 2 days (analysis of variance, p < 0.05). The presence of retroviral sequences in the genome of transduced EC was confirmed by Southern blot analysis. At 14 days, increased EC numbers were observed in vector-exposed wells compared with controls. Human tPA functional activity paralleled tPA antigen secretion. Genetically modified canine EC are capable of high levels of constitutive expression of human tPA after relatively short exposures to a retroviral vector containing the reporter gene. Increased cell number of tPA-transduced EC in culture suggests that tPA also may have other biologically important effects. These results support the efficacy of MFG-tPA gene transfer as a means of genetically modifying EC fibrinolytic activity and establishes the potential of this technology in vivo.


Asunto(s)
Endotelio Vascular/metabolismo , Retroviridae/genética , Activador de Tejido Plasminógeno/biosíntesis , Activador de Tejido Plasminógeno/genética , Transfección , Animales , Southern Blotting , Células Cultivadas , Perros , Vectores Genéticos , Inmunohistoquímica , Proteínas Recombinantes/biosíntesis , Transducción Genética
10.
Poult Sci ; 71(4): 744-6, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1594525

RESUMEN

There are great differences among species in the way pigment is deposited on the skin or in the egg yolk. Xanthophyll-type compounds produce the color. Consumers have associated a yellow color with a normal state of health. Many consumers insist on the color and indicate that increased cost is not much of a deterrent. At present, increasing the pigmenting properties of a poultry feed increases costs from $5 to $15/ton. Pigmentation is more costly in the fish industry and may increase the cost of the diet up to or over $100/ton, especially in the final 20% of the feed consumed before processing. The pigmentation should be consistent and uniform in both species. A history of high-pigment broilers is presented. High-pigment broilers lend themselves to effective television advertising.


Asunto(s)
Comportamiento del Consumidor , Preferencias Alimentarias , Pigmentación , Animales , Humanos , Estados Unidos
11.
West J Med ; 151(4): 459-60, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2588584
12.
DICP ; 23(7-8): 568-72, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2763579

RESUMEN

Interpatient variability in response to a given dose of meperidine, a synthetic opiate analgesic, may be partially explained by variability in plasma protein binding. Alpha 1-acid glycoprotein (AAG), a plasma protein that primarily binds basic drugs, has been shown to increase in patients during stress such as trauma or surgery. The objective of this study was to determine the extent of meperidine binding to AAG and albumin as a function of both protein and meperidine concentrations. We performed a simple extraction procedure and a highly sensitive gas chromatograph analytical procedure. The results indicated that meperidine binding did not vary significantly with meperidine concentration at a given AAG concentration. However, meperidine binding increased significantly (p less than 0.01) as AAG concentration increased. Conversely, meperidine binding to albumin appeared to be independent of concentration of either meperidine or albumin. In conclusion, alpha 1-acid glycoprotein is a major plasma protein which binds meperidine in patients during stress. Further studies are suggested to elucidate the role of AAG on the pharmacologic effects of meperidine.


Asunto(s)
Meperidina/sangre , Orosomucoide/metabolismo , Albúmina Sérica/metabolismo , Inhibidores de la Colinesterasa/sangre , Cromatografía de Gases , Humanos , Meperidina/análogos & derivados , Unión Proteica
13.
JAMA ; 261(20): 2991-4, 1989 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-2716131

RESUMEN

Of 18 nonblack patients with sickle cell disease, 14 had sickle cell anemia, 2 had hemoglobin SC disease, and 2 had hemoglobin S-beta o-thalassemia. The beta s gene cluster haplotypes that were determined in 7 patients were of African origin and were identified as Central African Republic, Central African Republic minor II, Benin, and Senegal. The haplotype Central African Republic minor II was present on the beta o-thalassemia chromosome in 2 patients. None of 10 patients whose alpha-gene status was determined had alpha-thalassemia-2. These data strongly support the concept that the beta s gene on chromosome 11 of these individuals is of African origin and that the alpha-gene locus on chromosome 16 is of white or native American origin. The clinical severity of the disease in these nonblack patients is appropriate to their haplotype without alpha-thalassemia-2 and is comparable with that of black patients. All persons with congenital hemolytic anemia should be examined for the presence of sickle cell disease regardless of physical appearance or ethnic background.


Asunto(s)
Anemia de Células Falciformes/genética , Globinas/genética , Haplotipos , Población Blanca , Adulto , África , Anemia de Células Falciformes/diagnóstico , Femenino , Hispánicos o Latinos , Humanos , Masculino , Mapeo Restrictivo , Talasemia/genética , Estados Unidos
14.
South Med J ; 77(10): 1316-8, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6207595

RESUMEN

We have described a previously unreported lesion--peritoneal keratin globules in uterine adenosquamous carcinoma. We postulate that the keratin globules are derived from sloughed uterine adenosquamous carcinoma which gains access to the peritoneum through retrograde dissemination via the fallopian tubes, and we suggest that the finding of these globules does not alter the prognosis and staging of the primary carcinoma.


Asunto(s)
Adenocarcinoma/metabolismo , Carcinoma de Células Escamosas/metabolismo , Queratinas/metabolismo , Peritoneo/metabolismo , Neoplasias Uterinas/metabolismo , Adenocarcinoma/patología , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Histocitoquímica , Humanos , Peritoneo/patología , Neoplasias Uterinas/patología
15.
J Anim Sci ; 58(3): 657-65, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6425258

RESUMEN

Five experiments were conducted to determine if boars and barrows differ in the level of dietary lysine required to maximize growth rate, efficiency of feed utilization, carcass leanness and N retention. In Exp. 1, 48 boars and 48 barrows were fed fortified corn-soybean meal diets calculated to contain 14 (grower) and 12% protein (finisher) and supplemented with 0, .15 or .30% lysine from 27 to 105 kg body weight. The basal diets analyzed .60 and .47% lysine, respectively. Linear improvements in feed/gain (P less than .01), backfat thickness (P less than .10), longissimus muscle area (P less than .01), and ham-loin (P less than .05) and lean cuts percentage (P less than .1) were observed in boars as dietary lysine increased. In barrows, however, growth rate, feed:gain ratio and carcass characteristics (except longissimus muscle area) were not significantly affected by dietary lysine level. In Exp. 2, 18 boars and 18 barrows initially averaging 64 kg body weight were fed a 12% protein diet (.47% lysine) supplemented with 0, .15 or .30% lysine. Linear (P less than .05) increases in N retention occurred in boars, but not barrows, as dietary lysine was increased. In Exp. 3 and 4, 140 boars (34 to 103 kg) were fed a 14-12% protein sequence (analyzed .61 and .48% lysine) supplemented with 0, .1, .2, .3 or .4% lysine. In Exp. 5, 60 boars (23 to 103 kg) were fed a 16-14% protein sequence (analyzed .83 and .68% lysine) supplemented with 0, .075, .15 or .225% lysine.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Castración/veterinaria , Lisina/metabolismo , Porcinos/crecimiento & desarrollo , Tejido Adiposo , Alimentación Animal , Animales , Composición Corporal , Peso Corporal , Lisina/administración & dosificación , Masculino , Nitrógeno/metabolismo , Necesidades Nutricionales , Porcinos/metabolismo
16.
Am J Dermatopathol ; 6 Suppl: 213-9, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6084956

RESUMEN

A case of a malignant neoplasm with features suggestive of both malignant melanoma and squamous cell carcinoma is reported. The neoplastic cells were positive for both S-100 protein and keratin when stained by the indirect peroxidase-antiperoxidase method. The literature on other instances of bi- or multidirectional differentiation of neoplastic cells is reviewed. The significance of these findings for terminology of neoplasms is discussed.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Faciales/patología , Melanoma/patología , Neoplasias Primarias Múltiples/patología , Anciano , Carcinoma de Células Escamosas/ultraestructura , Neoplasias Faciales/ultraestructura , Femenino , Humanos , Queratinas/análisis , Melanoma/ultraestructura , Neoplasias Primarias Múltiples/ultraestructura , Proteínas S100/análisis
18.
J Urol ; 130(1): 95-8, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6191050

RESUMEN

Prostatic specific acid phosphatase and prostatic specific antigen have been used as specific markers of prostatic adenocarcinoma in immunohistochemical studies, particularly when seeking the primary site of a poorly differentiated metastasis. We herein evaluate the effect of therapy on the persistence of these markers in surgically obtained tissues. Prostatic biopsies from 30 patients with adenocarcinoma of the prostate gland before and after treatment with orchiectomy alone, diethylstilbestrol, external beam radiation or combined radiation and diethylstilbestrol were studied for prostatic specific acid phosphatase and prostatic specific antigen using the indirect immunoperoxidase technique. The interval between biopsies ranged from 3 to 72 months, with an average of 28 months. All pre-treatment biopsies stained positively for prostatic specific acid phosphatase and prostatic specific antigen. Staining for prostatic specific antigen and prostatic specific acid phosphatase was seen easily in 29 of 30 post-treatment biopsies, while in 1 case infiltrating anaplastic cells surrounded by stroma showed staining for these antigens in an extremely small percentage of cells, which were overlooked easily unless examined carefully. In view of this small number of positively staining cells this case was designated as equivocal. While some cases demonstrated less intense staining in post-treatment biopsies compared to pre-treatment, this finding was by no means constant. With these primary antisera a higher percentage of cytologically malignant cells stained positively for prostatic specific acid phosphatase than for prostatic specific antigen in adjacent tissue sections in some cases. Prostatic specific acid phosphatase and prostatic specific antigen appear to be sensitive and persistent markers of prostatic adenocarcinoma despite morphologic changes accompanying various therapies.


Asunto(s)
Adenocarcinoma/inmunología , Neoplasias de la Próstata/inmunología , Fosfatasa Ácida/análisis , Fosfatasa Ácida/inmunología , Anciano , Antígenos de Neoplasias/análisis , Antígenos de Neoplasias/inmunología , Humanos , Técnicas Inmunológicas , Masculino , Persona de Mediana Edad , Antígeno Prostático Específico
19.
JAMA ; 246(17): 1931-3, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7197306

RESUMEN

A patient with thrombotic thrombocytopenic purpura (TTP) showed for the first time catastrophic signs and symptoms of CNS involvement immediately after infusion of platelets. Postmortem examination revealed extensive deposits of platelet aggregates within the small blood vessels of the brain, whereas lesions elsewhere in the body consisted of platelets as well as fibrin and were associated with endothelial proliferation and microaneurysm formation. These findings are consistent with the view that the initial event in TTP may be platelet aggregation. The plasma of this patient contained platelet-aggregating activity. We conclude that platelet transfusions in patients with TTP may aggravate the disease process.


Asunto(s)
Agregación Plaquetaria , Transfusión de Plaquetas , Púrpura Trombocitopénica Trombótica/terapia , Reacción a la Transfusión , Enfermedad Aguda , Adulto , Encéfalo/patología , Femenino , Humanos , Glomérulos Renales/patología , Miocardio/patología , Púrpura Trombocitopénica Trombótica/patología
20.
Transfusion ; 21(2): 228-9, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7222207
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