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1.
Opt Express ; 25(22): 26792-26801, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29092164

RESUMO

For photon-counting applications at ultraviolet wavelengths, there are currently no detectors that combine high efficiency (> 50%), sub-nanosecond timing resolution, and sub-Hz dark count rates. Superconducting nanowire single-photon detectors (SNSPDs) have seen success over the past decade for photon-counting applications in the near-infrared, but little work has been done to optimize SNSPDs for wavelengths below 400 nm. Here, we describe the design, fabrication, and characterization of UV SNSPDs operating at wavelengths between 250 and 370 nm. The detectors have active areas up to 56 µm in diameter, 70 - 80% efficiency at temperatures up to 4.2 K, timing resolution down to 60 ps FWHM, blindness to visible and infrared photons, and dark count rates of ∼ 0.25 counts/hr for a 56 µm diameter pixel. These performance metrics make UV SNSPDs ideal for applications in trapped-ion quantum information processing, lidar studies of the upper atmosphere, UV fluorescent-lifetime imaging microscopy, and photon-starved UV astronomy.

2.
APL Photonics ; 6(5)2021.
Artigo em Inglês | MEDLINE | ID: mdl-37621960

RESUMO

We developed superconducting nanowire single-photon detectors based on tungsten silicide, which show saturated internal detection efficiency up to a wavelength of 10 µm. These detectors are promising for applications in the mid-infrared requiring sub-nanosecond timing, ultra-high gain stability, low dark counts, and high efficiency, such as chemical sensing, LIDAR, dark matter searches, and exoplanet spectroscopy.

3.
Invest Ophthalmol Vis Sci ; 31(2): 258-61, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2303328

RESUMO

Dinitrophenyl (DNP) derivatives of various molecular weights were tested for their ability to elicit ocular anaphylaxis after topical application to the eye of immunized animals. Adult male Sprague-Dawley rats were immunized by intraperitoneal injection of DNP-Ascaris suum extracts and alum and were then skin-tested with DNP-bovine serum albumin on day 13 post-immunization to assess their sensitivity to the DNP hapten. On day 14, animals were challenged topically with DNP derivatives in one eye; PBS was applied to the contralateral, control eye. Animals were evaluated clinically, and ocular tissues were processed for histologic evaluation. The compounds used for topical ocular challenge included the DNP derivative of egg albumin (MW 43,500 D), soybean trypsin inhibitor (MW 20,080 D), insulin (MW 5733 D), B-chain insulin (MW 3496 D), and lysine (MW 478 D). Only di-DNP-lysine elicited clinical signs of redness, edema, and tearing and histologic evidence of mast cell degranulation. None of the other compounds, tested in solutions of either equal numbers of milligram per milliliter or equimolar concentrations, elicited ocular anaphylaxis after topical application. A compound of low molecular weight, less than 3496, is needed to elicit ocular anaphylaxis when applied topically.


Assuntos
Anafilaxia/etiologia , Antígenos/imunologia , Túnica Conjuntiva/imunologia , Dinitrofenóis/farmacocinética , Administração Tópica , Animais , Antígenos/administração & dosagem , Túnica Conjuntiva/metabolismo , Túnica Conjuntiva/patologia , Dinitrofenóis/administração & dosagem , Masculino , Mastócitos/imunologia , Peso Molecular , Ratos , Ratos Endogâmicos
4.
Obstet Gynecol ; 51(6): 713-7, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-662251

RESUMO

Two consecutive Papanicolaou smears were obtained in 3524 patients during a single clinic visit. The first smear consisted of a combined cervical scrape and vaginal pool sample (Fast smear) while the second smear contained only a cervical scrape. Of the 93 patients with abnormal cytology, 71 (76%) patients were identified by the first smear and 74 (80%) by the second smear. The interpretation of the two smears correlated in 51 patients (54.8%). Of the remaining 42 patients, the cytologic findings were more advanced in the second smear in 19 cases, and in 23 cases the reverse was true. There were 19 instances in which the cytologic findings were suspicious or positive. In 8 (42.1%) of these 19, one of the two smears contained either negative (7) or atypical (1) cytologic findings. The histologic diagnosis corresponded to the more advanced cytologic findings in all cases. The addition of the second cervical smear increased the detection rate of suspicious of positive cytology by 26.3%.


Assuntos
Teste de Papanicolaou , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal , Biópsia , Citodiagnóstico , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico
5.
Am J Surg ; 146(6): 712-4, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6316797

RESUMO

Nine cases of cystosarcoma phylloides in adolescent female patients are reported along with an additional 35 cases collected from the literature. Analysis of these 44 cases revealed 37 (84.1 percent) benign lesions, 6 (13.6 percent) malignant tumors, and 1 borderline lesion. Excision was the most common operative procedure and was performed in 35 patients. Nine patients underwent mastectomy. There were three recurrent lesions (one benign and two malignant) for a recurrence rate of 6.8 percent. Wide excision was successful in the treatment of recurrent lesions. On the basis of these data, excision is the preferred initial therapy of cystosarcoma phylloides in the adolescent patient regardless of the histologic classification of the lesion. Malignant cystosarcoma is more likely to recur than a benign lesion but a recurrence can be managed with reexcision. Sacrifice of the adolescent breast at the initial procedure is strongly discouraged.


Assuntos
Neoplasias da Mama/cirurgia , Tumor Filoide/cirurgia , Adolescente , Neoplasias da Mama/patologia , Criança , Feminino , Seguimentos , Humanos , Mastectomia , Recidiva Local de Neoplasia , Tumor Filoide/patologia
6.
Am J Surg ; 146(6): 770-3, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6650760

RESUMO

Although the incidence of anastomotic false aneurysms decreased precipitously with the cessation of usage of silk sutures for vascular anastomoses, the prevalence of these aneurysms has undoubtedly increased in keeping with an ever-increasing volume of peripheral vascular operations. Most aneurysms occur at femoral anastomoses and are easily diagnosed, since most patients present with a groin mass. Anastomotic aneurysms cannot be considered innocuous. Some may rupture and others have been associated with limb ischemia due to acute thrombosis or embolism. Thus, surgical correction is indicated for most anastomotic aneurysms. Patients at high risk with small aneurysms in accessible locations may, however, be followed if they are asymptomatic and there is no evidence of enlargement of the aneurysm [5].


Assuntos
Aneurisma/etiologia , Prótese Vascular/efeitos adversos , Artéria Femoral/cirurgia , Artéria Ilíaca/cirurgia , Artéria Poplítea/cirurgia , Adulto , Idoso , Aneurisma/cirurgia , Aneurisma Aórtico/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suturas , Tromboembolia/etiologia
7.
Am Surg ; 44(6): 382-7, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-677575

RESUMO

A total of 95 cases of metastasizing basal cell carcinomas have been recorded in the literature with 20 of these metastatic to bone. Two additional cases of metastasizing basal cell carcinoma with osseous metastases are presented, with a review of the literature.


Assuntos
Carcinoma Basocelular , Neoplasias Cutâneas , Adulto , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/patologia , Neoplasias Ósseas/terapia , Carcinoma Basocelular/patologia , Carcinoma Basocelular/cirurgia , Carcinoma Basocelular/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/terapia
8.
J Exp Anal Behav ; 28(3): 233-41, 1977 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-411870

RESUMO

Head orientation during auditory discriminations was studies in squirrel monkeys using a two-lever trial-by-trial procedure. Animals were studied using auditory discriminations based on the position of the sound and on the spectral content differences between a pure tone and a noise. After the percentage of correct responses reached asymptote, head orientation was measured using videotape recordings. Orientation occurred on virtually every trial and was under the control of the position of the sound under all conditions. Lever responding was controlled by the same parameters of the sound under some conditions, and by different parameters in others. Orientation and lever responding were correlated (a level response could be predicted from the direction of orientation) when both responses were under the control of the same parameters of the sound. The two responses were uncorrelated when they were controlled by different parameters of the sound. Orientation and lever responding were not functionally related.


Assuntos
Percepção Auditiva , Condicionamento Operante , Discriminação Psicológica , Orientação , Animais , Haplorrinos , Humanos , Masculino , Discriminação da Altura Tonal , Saimiri , Percepção Espacial
9.
Theriogenology ; 51(3): 583-95, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10729044

RESUMO

The effects of bovine oviductal proteins on bull sperm viability, acrosome reaction and motility were studied. Motile frozen/thawed spermatozoa from Percoll gradients were incubated with 1.0 mg/mL oviductal proteins (>8 kDa) extracted by ammonium sulphate precipitation from oviductal extract (OE) or serum-free oviductal epithelial cell-conditioned media (CM), treated in the presence (CM+) or absence (CM-) of 1 microg/mL 17beta-estradiol. Inclusion of oviductal proteins had a significant beneficial effect on sperm viability (76.3 to 80.6%+/-5.3) compared with the control (without oviductal proteins; 57.8%+/-5.3) immediately after the commencement of incubation. After 5 h, viability was significantly higher for CM- and OE treatments than for the control, although no differences were observed at 24 h. Acrosomal status only differed among treatments after 24 h, when higher percentages of acrosome- reacted spermatozoa were found in the control (46.0%+/-2.5) than in the oviductal protein treatments (33.1 to 38.2%+/-2.5). No differences in percentages of motile spermatozoa occurred within the first hour of incubation, although inclusion of CM proteins decreased sperm velocities, beat cross frequency, linearity, and straightness but increased values for mean angular displacement. These findings suggest that proteins secreted by oviductal epithelium promote viability, delay the acrosome reaction and suppress the motion of spermatozoa.


Assuntos
Tubas Uterinas/metabolismo , Proteínas/farmacologia , Espermatozoides/efeitos dos fármacos , Reação Acrossômica/efeitos dos fármacos , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados , Epitélio/metabolismo , Estradiol/farmacologia , Feminino , Masculino , Proteínas/metabolismo , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Extratos de Tecidos/farmacologia
16.
Ment Retard ; 28(3): 163-8, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2366658

RESUMO

Absenteeism of 130 direct-care staff was reduced by 27% through a mixed consequence procedure consisting of positive reinforcement for reliable attendance and punishment (progressive discipline) for attendance abuse. Reduced rates of absenteeism were maintained over a 12-month period. A 17% reduction in overtime and an increase in annual staff turnover from 34% to 45% also occurred. Results extend the findings of mixed consequence procedures to residential facilities for persons with developmental disabilities. Development of a more powerful positive reinforcement component was discussed.


Assuntos
Absenteísmo , Educação de Pessoa com Deficiência Intelectual , Disciplina no Trabalho/métodos , Planos para Motivação de Pessoal , Gestão de Recursos Humanos/métodos , Adolescente , Adulto , Negociação Coletiva , Hospitais Estaduais , Humanos , Massachusetts , Recursos Humanos
17.
Clin Obstet Gynecol ; 32(4): 858-69, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2692917

RESUMO

Reconstruction of the breast after mastectomy is today totally possible assuming no major medical contraindications. Contemporary surgical and technical refinements no longer allow as adequate creation of a chest mound that must be covered by conservative clothing. Instead, the usual result of a completed reconstructive effort should be viewed as most normal, aesthetic, and pleasing by the patient, the reconstructive surgeon, and the impartial family physician. It is perhaps not too bold to state that there is practically no mastectomy circumstance that does not lend itself to a reconstructive effort where highly acceptable results can be expected. The surgical techniques are widely available in almost every community. The most important component of the reconstructive effort, however, is the careful selection of procedures for the individual patient. This is accomplished only after thorough assessment and open discussions to educate the patient about the realistic available alternatives.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia/reabilitação , Cirurgia Plástica/métodos , Feminino , Humanos , Mamilos , Cuidados Pré-Operatórios , Próteses e Implantes , Retalhos Cirúrgicos
18.
Ann Plast Surg ; 3(6): 549-54, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-546300

RESUMO

A total of 97 cases of metastatic basal cell carcinoma have been reported in the literature, 22 of which were metastatic to bone. To date there has been no survival following bone metastasis. A case report of significant long-term survival--over three times the expected--is presented. The treatment described is perhaps a guideline for management of basal cell carcinoma metastatic to bone, though it is presumed the basic biological nature of the tumor determines length and quality of survival.


Assuntos
Neoplasias Ósseas/secundário , Carcinoma Basocelular/mortalidade , Adulto , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/terapia , Carcinoma Basocelular/terapia , Neoplasias Faciais/mortalidade , Neoplasias Faciais/terapia , Humanos , Masculino
19.
Aesthetic Plast Surg ; 4(1): 373-7, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24174103

RESUMO

The Berkeley procedure in the treatment of unilateral cleft lip-nose deformity approaches the deformed ala as an anatomic unit, rotating and repositioning the entire ala into a proper anatomic perspective. Between 1971 and 1978, a total of 55 patients were operated on by means of the Berkeley procedure. The results were reviewed by physicians, patients, and parents as to aesthetic acceptability and anatomic alignment. Both criteria were uniformaly rated good to excellent. There were no immediate or late complications, and the scars were determined to be acceptable to excellent.

20.
Ophthalmic Res ; 24(1): 45-50, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1376886

RESUMO

Conjunctival tissue of 12 guinea pigs (6 experimental animals, 6 controls) was sensitized with IgG1 (PCA titer 1:2,000) antisera to dinitrophenol carrier and challenged topically with hapten. Periorbital swelling, conjunctival edema and conjunctival redness were evaluated clinically at 0.5 h and hourly for 12 h, and again at 24 and 48 h. Tears were collected at each time point for cytology. Results showed an early-phase reaction (EPR) peaking at 0.5 h and a late-phase reaction (LPR) peaking at 5-7 h. Periorbital swelling was minimal 4 h after appearance of the EPR. Conjunctival edema and redness increased in both the early and late phases, but without two distinct peaks. However, individual animals in both groups did show biphasic reactions. Tear cytology showed an abnormal increase in neutrophils and eosinophils in the later time periods and was a significant way to detect ocular anaphylaxis. In conclusion, if the presence of two significant peaks of clinical inflammation after one antigen challenge is taken as the narrowest definition of a late phase in anaphylaxis, our results show an ocular LPR occurring in our animal model.


Assuntos
Conjuntivite Alérgica/imunologia , Hipersensibilidade Imediata/imunologia , Animais , Conjuntivite Alérgica/patologia , Dinitrofenóis , Eosinófilos , Feminino , Cobaias , Hipersensibilidade Imediata/patologia , Contagem de Leucócitos , Lisina/administração & dosagem , Lisina/análogos & derivados , Neutrófilos , Lágrimas/citologia , gama-Globulinas
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