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1.
Phys Rev Lett ; 130(17): 173001, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172243

RESUMO

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst) eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

2.
Phys Rev Lett ; 128(11): 112503, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363014

RESUMO

We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst) eV and 6463.7±0.3(stat)±0.1(syst) eV, and widths to be 2.5±1.0(stat)±0.4(syst) eV and 1.0±0.6(stat)±0.3(stat) eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.

3.
Global Health ; 18(1): 24, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193629

RESUMO

BACKGROUND: Healthcare workers are at a disproportionate risk of contracting COVID-19. The physical and mental repercussions of such risk have an impact on the wellbeing of healthcare workers around the world. Healthcare workers are the foundation of all well-functioning health systems capable of responding to the ongoing pandemic; initiatives to address and reduce such risk are critical. Since the onset of the pandemic healthcare organizations have embarked on the implementation of a range of initiatives designed to improve healthcare worker health and wellbeing. METHODS: Through a qualitative collective case study approach where participants responded to a longform survey, the facilitators, and barriers to implementing such initiatives were explored, offering global insights into the challenges faced at the organizational level. 13 healthcare organizations were surveyed across 13 countries. Of these 13 participants, 5 subsequently provided missing information through longform interviews or written clarifications. RESULTS: 13 case studies were received from healthcare provider organizations. Mental health initiatives were the most commonly described health and wellbeing initiatives among respondents. Physical health and health and safety focused initiatives, such as the adaption of workspaces, were also described. Strong institutional level direction, including engaged leadership, and the input, feedback, and engagement of frontline staff were the two main facilitators in implementing initiatives. The most common barrier was HCWs' fear of contracting COVID-19 / fear of passing COVID-19 to family members. In organizations who discussed infection prevention and control initiatives, inadequate personal protective equipment and supply chain disruption were highlighted by respondents. CONCLUSIONS: Common themes emerge globally in exploring the enablers and barriers to implementing initiatives to improve healthcare workers health and wellbeing through the COVID-19 pandemic. Consideration of the themes outlined in the paper by healthcare organizations could help influence the design and deployment of future initiatives ahead of implementation.


Assuntos
COVID-19 , Pandemias , Pessoal de Saúde/psicologia , Humanos , Pandemias/prevenção & controle , Equipamento de Proteção Individual , SARS-CoV-2
4.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397250

RESUMO

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35529769

RESUMO

Feature sizes in integrated circuits have decreased substantially over time, and it has become increasingly difficult to three-dimensionally image these complex circuits after fabrication. This can be important for process development, defect analysis, and detection of unexpected structures in externally sourced chips, among other applications. Here, we report on a non-destructive, tabletop approach that addresses this imaging problem through x-ray tomography, which we uniquely realize with an instrument that combines a scanning electron microscope (SEM) with a transition-edge sensor (TES) x-ray spectrometer. Our approach uses the highly focused SEM electron beam to generate a small x-ray generation region in a carefully designed target layer that is placed over the sample being tested. With the high collection efficiency and resolving power of a TES spectrometer, we can isolate x-rays generated in the target from background and trace their paths through regions of interest in the sample layers, providing information about the various materials along the x-ray paths through their attenuation functions. We have recently demonstrated our approach using a 240 Mo/Cu bilayer TES prototype instrument on a simplified test sample containing features with sizes of ∼ 1 µm. Currently, we are designing and building a 3000 Mo/Au bilayer TES spectrometer upgrade, which is expected to improve the imaging speed by factor of up to 60 through a combination of increased detector number and detector speed.

6.
Opt Express ; 27(4): 4386-4403, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30876058

RESUMO

Transverse mode competition and instabilities in high-power fiber oscillators have been studied experimentally by monitoring the dynamic power exchanges and characteristic frequencies of the transmitted fundamental mode (FM) and scattered high-order modes (HOMs) of the fiber laser cavity under CW and pulsed pumping. The FM and HOM power evolution indicates the presence of two competing effective laser cavities which result in rich output dynamics and full chaotic operation. The thermal and inversion related contributions to the observed instabilities have been identified by monitoring the associated characteristic instability frequencies under pulsed pumping. It is shown that in the transient regime, both inversion and thermal effects contribute successively to the observed power instabilities. Increasing the pump power leads to full chaotic response through an interplay between transverse and longitudinal mode instabilities.

7.
IEEE Trans Appl Supercond ; 29(5)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31360051

RESUMO

Readout of a large, spacecraft-based array of superconducting transition-edge sensors (TESs) requires careful management of the layout area and power dissipation of the cryogenic-circuit components. We present three optimizations of our time- (TDM) and code-division-multiplexing (CDM) systems for the X-ray Integral Field Unit (X-IFU), a several-thousand-pixel-TES array for the planned Athena-satellite mission. The first optimization is a new readout scheme that is a hybrid of CDM and TDM. This C/TDM architecture balances CDM's noise advantage with TDM's layout compactness. The second is a redesign of a component: the shunt resistor that provides a dc-voltage bias to the TESs. A new layout and a thicker Pd-Au resistive layer combine to reduce this resistor's area by more than a factor of 5. Third, we have studied the power dissipated by the first-stage SQUIDs (superconducting quantum-interference devices) and the readout noise versus the critical current of the first-stage SqUIDs. As a result, the X-IFU TDM and C/TDM SQUIDs will have a specified junction critical current of 5 µA. Based on these design optimizations and TDM experiments described by Durkin, et al. (these proceedings), TDM meets all requirements to be X-IFU's backup-readout option. Hybrid C/TDM is another viable option that could save spacecraft resources.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31160861

RESUMO

Time-division multiplexing (TDM) is the backup readout technology for the X-ray Integral Field Unit (X-IFU), a 3,168-pixel X-ray transition-edge sensor (TES) array that will provide imaging spectroscopy for ESA's Athena satellite mission. X-0IFU design studies are considering readout with a multiplexing factor of up to 40. We present data showing 40-row TDM readout (32 TES rows + 8 repeats of the last row) of TESs that are of the same type as those being planned for X-IFU, using measurement and analysis parameters within the ranges specified for X-IFU. Singlecolumn TDM measurements have best-fit energy resolution of (1.91 ± 0.01) eV for the Al Kα complex (1.5 keV), (2.10 ± 0.02) eV for Ti Kα (4.5 keV), (2.23 ± 0.02) eV for Mn Kα (5.9 keV), (2.40 ± 0.02) eV for Co Kα (6.9 keV), and (3.44 ± 0.04) eV for Br Kα (11.9 keV). Three-column measurements have best-fit resolution of (2.03 ± 0.01) eV for Ti Kα and (2.40 ± 0.01) eV for Co Kα. The degradation due to the multiplexed readout ranges from 0.1 eV at the lower end of the energy range to 0.5 eV at the higher end. The demonstrated performance meets X-IFU's energy-resolution and energy-range requirements. True 40-row TDM readout, without repeated rows, of kilopixel scale arrays of X-IFU-like TESs is now under development.

9.
Opt Lett ; 38(22): 4686-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24322106

RESUMO

We present a pulsed fiber laser system with average power up to 265 W, pulse energy up to 10.6 mJ, pulse duration adjustable in the range 500 ps-500 ns, repetition rate fully controllable from single-shot operation up to 1 MHz, and the ability to control peak power independently of pulse energy. The system has a compact, all-spliced construction. Such a versatile laser will have wide applications in materials processing.

10.
Br J Dermatol ; 169(6): 1272-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23855783

RESUMO

BACKGROUND: Long-standing concerns over the vitamin D status of South Asian adults in the U.K. require studies using statistically valid sample sizes to measure annual variation and contributory lifestyle factors. OBJECTIVES: To measure annual variation in the vitamin D status of U.K. South Asians, to determine the associated lifestyle influences, and to compare these with a similar study of white adults. METHODS: A single-centre, prospective cohort study measuring circulating 25-hydroxyvitamin D [25(OH)D], sunlight exposure levels and lifestyle factors for 1 year in 125 ambulant South Asian adults with sun-reactive skin type V, aged 20-60 years, in Greater Manchester, U.K. (53·5°N). RESULTS: The 25(OH)D levels of South Asians were alarmingly low. In summer, their median 25(OH)D level was 9·0 ng mL(-1) , [interquartile range (IQR) 6·7-13·1], falling to 5·8 ng mL(-1) (IQR 4·0-8·1) in winter. This compared with values in the white population of 26·2 ng mL(-1) (IQR 19·9-31·5) in summer and 18·9 ng mL(-1) IQR (11·6-23·7) in winter. Median daily dietary vitamin D was lower in South Asians (1·32 µg vs. 3·26 µg for white subjects) and was compounded by low supplement use. Despite similar times spent outdoors, ultraviolet (UV) dosimeters recorded lower personal UV exposure among South Asians, indicating sun avoidance when outside, while sun exposure diaries recorded lower amounts of skin surface exposure. CONCLUSIONS: The majority of South Asians never reached sufficiency in vitamin D status. Lifestyle differences, with lower oral intake, sun exposure and rates of cutaneous production due to darker skin, indicate that standard advice on obtaining sufficient vitamin D needs modification for the South Asian community in the U.K.


Assuntos
Estilo de Vida/etnologia , Luz Solar , Deficiência de Vitamina D/etiologia , Vitamina D/análogos & derivados , Adulto , Idoso , Bangladesh/etnologia , Estudos de Casos e Controles , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/etnologia , Estudos Prospectivos , Estações do Ano , Pele/efeitos da radiação , Pigmentação da Pele/fisiologia , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/etnologia , Adulto Jovem
11.
Br J Dermatol ; 163(5): 1050-5, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20716215

RESUMO

BACKGROUND: Vitamin D is necessary for bone health and is potentially protective against a range of malignancies. Opinions are divided on whether the proposed optimal circulating 25-hydroxyvitamin D [25(OH)D] level (≥ 32 ng mL⁻¹) is an appropriate and feasible target at population level. OBJECTIVES: We examined whether personal sunlight exposure levels can provide vitamin D sufficient (≥ 20 ng mL⁻¹) and optimal status in the U.K. public. METHODS: This prospective cohort study measured circulating 25(OH)D monthly for 12 months in 125 white adults aged 20-60 years in Greater Manchester. Dietary vitamin D and personal ultraviolet radiation (UVR) exposure were assessed over 1-2 weeks in each season. The primary analysis determined the post-summer peak 25(OH)D required to maintain sufficiency in wintertime. RESULTS: Dietary vitamin D remained low in all seasons (median 3·27 µg daily, range 2·76-4·15) while personal UVR exposure levels were high in spring and summer, low in autumn and negligible in winter. Mean 25(OH)D levels were highest in September [28·4 ng mL⁻¹; 28% optimal, zero deficient (<5 ng mL⁻¹)], and lowest in February (18·3 ng mL⁻¹; 7% optimal, 5% deficient). A February 25(OH)D level of 20 ng mL⁻¹ was achieved following a mean (95% confidence interval) late summer level of 30·4 (25·6-35·2) and 34·9 (27·9-41·9) ng mL⁻¹ in women and men, respectively, with 62% of variance explained by gender and September levels. CONCLUSIONS: Late summer 25(OH)D levels approximating the optimal range are required to retain sufficiency throughout the U.K. winter. Currently the majority of the population fails to reach this post-summer level and becomes vitamin D insufficient during the winter.


Assuntos
Luz Solar , Vitamina D/análogos & derivados , Vitamina D/administração & dosagem , Vitaminas/administração & dosagem , Adulto , Estudos de Coortes , Dieta , Inglaterra , Feminino , Análise de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Estudos Prospectivos , Estações do Ano , Fatores Sexuais , Raios Ultravioleta , Vitamina D/análise , Vitamina D/sangue , Adulto Jovem
12.
Br J Dermatol ; 163(4): 817-22, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20545692

RESUMO

BACKGROUND: Photosensitivity disorders involve an abnormal skin reaction to sunlight exposure and affect a substantial percentage of the population. No previous studies have directly compared lifestyle attributes between photosensitive and healthy individuals. OBJECTIVES: To assess the impact of photosensitivity on time spent outdoors in the U.K., holiday behaviour, use of sunscreens and vitamin D supplements, and employment status. METHODS: Questionnaires were completed by ambulant photosensitive and healthy adults aged 18-60 years residing in Greater Manchester. RESULTS: Forty-five adults with moderate-severe photosensitivity and 124 healthy adults completed the questionnaire. This revealed that photosensitive subjects spent significantly less time outdoors in the U.K. on both summer weekdays (P < 0·01) and summer weekends (P < 0·0001) than healthy subjects, took fewer holidays per year (P < 0·05), and spent less time outdoors on a sunny holiday (P < 0·0001). They wore clothing that covered a wider skin area (P < 0·0001), and use of sunscreen was greater (both frequency of application and area covered) in the photosensitive group outside of holiday time (P < 0·0001), but not when on a sunny holiday, as healthy people increased their sunscreen use at this time. Despite the reduced sun exposure, photosensitive subjects were no more likely to take vitamin D supplements than healthy subjects were; they also exhibited a significantly higher rate of unemployment (P < 0·05). CONCLUSIONS: Photosensitivity disorders negatively influence lifestyle including employment status; more attention is required to the socioeconomic impact of these conditions.


Assuntos
Estilo de Vida , Transtornos de Fotossensibilidade/reabilitação , Adolescente , Adulto , Uso de Medicamentos/estatística & dados numéricos , Emprego/estatística & dados numéricos , Feminino , Férias e Feriados/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Fotossensibilidade/etiologia , Transtornos de Fotossensibilidade/prevenção & controle , Estações do Ano , Fatores Socioeconômicos , Luz Solar/efeitos adversos , Protetores Solares/administração & dosagem , Fatores de Tempo , Vitamina D/administração & dosagem , Adulto Jovem
13.
J Cell Biol ; 107(6 Pt 2): 2749-56, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3264556

RESUMO

Entactin (nidogen), a 150-kD sulfated glycoprotein, is a major component of basement membranes and forms a highly stable noncovalent complex with laminin. The complete amino acid sequence of mouse entactin has been derived from sequencing of cDNA clones. The 5.9-kb cDNA contains a 3,735-bp open reading frame followed by a 3'-untranslated region of 2.2 kb. The open reading frame encodes a 1,245-residue polypeptide with an unglycosylated Mr of 136,500, a 28-residue signal peptide, two Asn-linked glycosylation sites, and two potential Ca2+-binding sites. Analysis of the deduced amino acid sequence predicts that the molecule consists of two globular domains of 70 and 36 kD separated by a cysteine-rich domain of 28 kD. The COOH-terminal globular domain shows homology to the EGF precursor and the low density lipoprotein receptor. Entactin contains six EGF-type cysteine-rich repeat units and one copy of a cysteine-repeat motif found in thyroglobulin. The Arg-Gly-Asp cell recognition sequence is present in one of the EGF-type repeats, and a synthetic peptide from the putative cell-binding site of entactin was found to promote the attachment of mouse mammary tumor cells.


Assuntos
Membrana Basal/análise , Fator de Crescimento Epidérmico/genética , Glicoproteínas/genética , Glicoproteínas de Membrana , Precursores de Proteínas/genética , Receptores de LDL/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Adesão Celular , Linhagem Celular , Clonagem Molecular , DNA/genética , Glicoproteínas/análise , Camundongos , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico
14.
J Cell Biol ; 127(6 Pt 1): 1767-75, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7798325

RESUMO

Tetranectin is a protein shared by the blood and the extracellular matrix. Tetranectin is composed of four identical, noncovalently bound polypeptides each with a molecular mass of approximately 21 kD. There is some evidence that tetranectin may be involved in fibrinolysis and proteolysis during tissue remodeling, but its precise biological function is not known. Tetranectin is enriched in the cartilage of the shark, but the gene expression pattern in the mammalian skeletal system has not been determined. In the present study we have examined the expression pattern and putative function of tetranectin during osteogenesis. In the newborn mouse, strong tetranectin immunoreactivity was found in the newly formed woven bone around the cartilage anlage in the future bone marrow and along the periosteum forming the cortex. No tetranectin immunoreactivity was found in the proliferating and hypertrophic cartilage or in the surrounding skeletal muscle. Using an in vitro mineralizing system, we examined osteoblastic cells at different times during their growth and differentiation. Tetranectin mRNA appeared in the cultured osteoblastic cells in parallel with mineralization, in a pattern similar to that of bone sialoprotein, which is regarded as one of the late bone differentiation markers. To explore the putative biological role of tetranectin in osteogenesis we established stably transfected cell lines (PC12-tet) overexpressing recombinant tetranectin as evidenced by Northern and Western blot analysis and immunoprecipitation. Both control PC12 cells and PC12-tet cells injected into nude mice produced tumors containing bone material, as evidenced by von Kossa staining for calcium and immunostaining with bone sialoprotein and alkaline phosphatase antiserum. Nude mice tumors established from PC12-tet cells contained approximately fivefold more bone material than those produced by the untransfected PC12 cell line or by the PC12 cells transfected with the expression vector with no insert (Mann Whitney rank sum test, p < 0.01), supporting the notion that tetranectin may play an important direct and/or indirect role during osteogenesis. In conclusion, we have established a potential role for tetranectin as a bone matrix protein expressed in time and space coincident with mineralization in vivo and in vitro.


Assuntos
Proteínas Sanguíneas/fisiologia , Calcificação Fisiológica/fisiologia , Lectinas Tipo C , Osteogênese/fisiologia , Animais , Sequência de Bases , Biomarcadores , Proteínas Sanguíneas/genética , Osso e Ossos/citologia , Bovinos , Diferenciação Celular , Células Cultivadas , Expressão Gênica , Imuno-Histoquímica , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Neoplasias Experimentais , Células PC12 , RNA Mensageiro/análise , Ratos , Proteínas Recombinantes/metabolismo , Transfecção
15.
J Dent Res ; 98(10): 1081-1087, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31314998

RESUMO

Dentists prescribe a large portion of all oral antibiotics, and these are associated with a risk of adverse drug reactions (ADRs). The aim of this study was to quantify the risk of ADRs associated with oral antibiotics commonly prescribed by dentists. NHS Digital Prescribing data and Yellow Card Drug Analysis data for 2010 to 2017 were abstracted to quantify dental antibiotic prescribing in England, and the rate and types of ADRs associated with them. During the period of study, the mean number of actively practicing dentists in England was 23,624. Amoxicillin accounted for 64.8% of dental antibiotic prescribing and had the lowest reported rate of fatal ADRs (0.1/million prescriptions) and overall ADRs (21.5/million prescriptions). Indeed, amoxicillin was respectively 6 and 3 times less likely to cause an ADR than the other penicillins, penicillin V and amoxicillin + clavulanic acid, and appears to be very safe in patients with no history of penicillin allergy. In contrast, clindamycin, which is often used in patients with penicillin allergy, had the highest rate of fatal (2.9/million prescriptions) and overall (337.3/million prescriptions) ADRs, with Clostridiodes (formerly Clostridium) difficile infections pivotal to its ADR profile. Other amoxicillin alternatives, clarithromycin and metronidazole, while significantly worse than amoxicillin, were 3 and nearly 5 times less likely to cause an ADR than clindamycin. Ranked from least to most likely to cause an ADR, antibiotics most commonly prescribed were as follows: amoxicillin < cephalosporins < erythromycin < tetracyclines < azithromycin < metronidazole < amoxicillin + clavulanic acid < clarithromycin < penicillin V < clindamycin. This study confirmed the high level of safety associated with use of amoxicillin by dentists and the significantly worse rates of fatal and nonfatal ADRs associated with other penicillins and alternatives to amoxicillin for those who are penicillin allergic. In particular, clindamycin had the highest rate of fatal and nonfatal ADRs of any of the antibiotics commonly prescribed by dentists.


Assuntos
Amoxicilina/efeitos adversos , Antibacterianos/efeitos adversos , Claritromicina/efeitos adversos , Clindamicina/efeitos adversos , Metronidazol/efeitos adversos , Administração Oral , Sistemas de Notificação de Reações Adversas a Medicamentos , Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Claritromicina/administração & dosagem , Clindamicina/administração & dosagem , Odontólogos , Inglaterra , Humanos , Metronidazol/administração & dosagem , Penicilinas/administração & dosagem , Penicilinas/efeitos adversos
16.
Rev Sci Instrum ; 90(12): 123107, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893849

RESUMO

We report on the design, commissioning, and initial measurements of a Transition-Edge Sensor (TES) x-ray spectrometer for the Electron Beam Ion Trap (EBIT) at the National Institute of Standards and Technology (NIST). Over the past few decades, the NIST EBIT has produced numerous studies of highly charged ions in diverse fields such as atomic physics, plasma spectroscopy, and laboratory astrophysics. The newly commissioned NIST EBIT TES Spectrometer (NETS) improves the measurement capabilities of the EBIT through a combination of high x-ray collection efficiency and resolving power. NETS utilizes 192 individual TES x-ray microcalorimeters (166/192 yield) to improve upon the collection area by a factor of ∼30 over the 4-pixel neutron transmutation doped germanium-based microcalorimeter spectrometer previously used at the NIST EBIT. The NETS microcalorimeters are optimized for the x-ray energies from roughly 500 eV to 8000 eV and achieve an energy resolution of 3.7 eV-5.0 eV over this range, a more modest (<2×) improvement over the previous microcalorimeters. Beyond this energy range, NETS can operate with various trade-offs, the most significant of which are reduced efficiency at lower energies and being limited to a subset of the pixels at higher energies. As an initial demonstration of the capabilities of NETS, we measured transitions in He-like and H-like O, Ne, and Ar as well as Ni-like W. We detail the energy calibration and data analysis techniques used to transform detector counts into x-ray spectra, a process that will be the basis for analyzing future data.

17.
Oncogene ; 26(31): 4580-9, 2007 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-17297465

RESUMO

Two related Rho GTPase-activating proteins, DLC-1 (deleted in liver cancer 1) and DLC-2, are emerging as bona fide tumor suppressor genes that inhibit cancer cell growth. In this report, we characterized a gene on chromosome Xq13 that encodes DLC-3 (also known as KIAA0189 and STARD8), a third member of the DLC family. The DLC-3 gene has transcripts with alternative 5' ends, one of which, DLC-3alpha, encodes an 1103-amino acid polypeptide highly similar to DLC-1 and DLC-2. A second isoform (DLC-3beta) would yield a protein lacking the N-terminal sterile alpha motif domain. The DLC-3 gene is widely expressed in normal tissues, but DLC-3 mRNA levels were low or absent in a significant number of breast, ovarian, liver and prostate cancer cell lines. Using a cancer profiling array to compare matched tumor and normal human tissues, downregulation of DLC-3 mRNA was observed in kidney, lung, ovarian, uterine and breast cancer samples. By quantitative reverse transcriptase-polymerase chain reaction, DLC-3 expression was reduced in primary prostate carcinomas relative to normal prostate tissue. Transfection of human breast and prostate cancer cells with a DLC-3alpha expression vector inhibited cell proliferation, colony formation and growth in soft agar. These results indicate that deregulation of DLC-3 may contribute to breast and prostate tumorigenesis.


Assuntos
Proteínas Ativadoras de GTPase/metabolismo , Neoplasias/metabolismo , Proteínas Supressoras de Tumor/genética , Sequência de Aminoácidos , Mama/metabolismo , Neoplasias da Mama/metabolismo , Proliferação de Células , Regulação para Baixo , Feminino , Genes Supressores de Tumor , Humanos , Masculino , Dados de Sequência Molecular , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
J Vet Intern Med ; 22(4): 839-43, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18482276

RESUMO

BACKGROUND: Early diagnosis and treatment are associated with an improved prognosis in blastomycosis. The diagnosis of blastomycosis may be missed by cytology, histopathology, culture, or serology. An enzyme immunoassay (EIA) for detection of Blastomyces dermatitidis galactomannan antigen in body fluids has been used for rapid diagnosis of blastomycosis in humans. HYPOTHESIS: Measurement of Blastomyces antigen in urine or serum by the MVista Blastomyces antigen EIA is more sensitive than measurement of anti-Blastomyces antibodies for diagnosis of blastomycosis in dogs. METHODS: Serum and urine samples from 46 dogs with confirmed blastomycosis were tested for Blastomyces antigen and serum was tested for anti-Blastomyces antibodies. RESULTS: The sensitivity for the detection of antigen in urine was 93.5% and it was 87.0% in serum. The sensitivity of antibody detection by agar gel immunodiffusion (AGID) was 17.4% and it was 76.1% by EIA. Antigen and antibody decreased during itraconazole treatment. CONCLUSIONS AND CLINICAL IMPORTANCE: Antigen detection is a more sensitive test for diagnosis of blastomycosis than antibody testing by AGID, the only commercially available method. Antigen concentrations decreased with treatment.


Assuntos
Anticorpos Antifúngicos/imunologia , Antígenos de Fungos/imunologia , Blastomicose/veterinária , Doenças do Cão/imunologia , Técnicas Imunoenzimáticas/veterinária , Animais , Anticorpos Antifúngicos/urina , Antifúngicos/uso terapêutico , Antígenos de Fungos/urina , Blastomyces/imunologia , Blastomicose/diagnóstico , Blastomicose/tratamento farmacológico , Blastomicose/imunologia , Doenças do Cão/tratamento farmacológico , Doenças do Cão/urina , Cães , Itraconazol/uso terapêutico , Sensibilidade e Especificidade , Fatores de Tempo
19.
Mol Cell Biol ; 21(22): 7817-25, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11604516

RESUMO

Tetranectin is a plasminogen-binding, homotrimeric protein belonging to the C-type lectin family of proteins. Tetranectin has been suggested to play a role in tissue remodeling, due to its ability to stimulate plasminogen activation and its expression in developing tissues such as developing bone and muscle. To test the functional role of tetranectin directly, we have generated mice with a targeted disruption of the gene. We report that the tetranectin-deficient mice exhibit kyphosis, a type of spinal deformity characterized by an increased curvature of the thoracic spine. The kyphotic angles were measured on radiographs. In 6-month-old normal mice (n = 27), the thoracic angle was 73 degrees +/- 2 degrees, while in tetranectin-deficient 6-month-old mice (n = 35), it was 93 degrees +/- 2 degrees (P < 0.0001). In approximately one-third of the mutant mice, X-ray analysis revealed structural changes in the morphology of the vertebrae. Histological analysis of the spines of these mice revealed an apparently asymmetric development of the growth plate and of the intervertebral disks of the vertebrae. In the most advanced cases, the growth plates appeared disorganized and irregular, with the disk material protruding through the growth plate. Tetranectin-null mice had a normal peak bone mass density and were not more susceptible to ovariectomy-induced osteoporosis than were their littermates as determined by dual-emission X-ray absorptiometry scanning. These results demonstrate that tetranectin plays a role in tissue growth and remodeling. The tetranectin-deficient mouse is the first mouse model that resembles common human kyphotic disorders, which affect up to 8% of the population.


Assuntos
Proteínas Sanguíneas/fisiologia , Cifose/etiologia , Lectinas Tipo C , Lectinas/fisiologia , Animais , Proteínas Sanguíneas/genética , Densidade Óssea , Suscetibilidade a Doenças , Feminino , Deleção de Genes , Marcação de Genes/métodos , Cifose/genética , Cifose/patologia , Lectinas/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoporose/etiologia , Ovariectomia , Vértebras Torácicas/anormalidades , Vértebras Torácicas/patologia
20.
J Autism Dev Disord ; 47(2): 285-296, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27830427

RESUMO

In this study, we explored potential associations among self-injurious behaviors (SIB) and a diverse group of protective and risk factors in children with autism spectrum disorder from two databases: Autism and Developmental Disabilities Monitoring (ADDM) Network and the Autism Speaks-Autism Treatment Network (AS-ATN). The presence of SIB was determined from children's records in ADDM and a parent questionnaire in AS-ATN. We used multiple imputation to account for missing data and a non-linear mixed model with site as a random effect to test for associations. Despite differences between the two databases, similar associations were found; SIB were associated with developmental, behavioral, and somatic factors. Implications of these findings are discussed in relation to possible etiology, future longitudinal studies, and clinical practice.


Assuntos
Transtorno do Espectro Autista/epidemiologia , Comportamento Autodestrutivo/epidemiologia , Criança , Comorbidade , Estudos Transversais , Bases de Dados Factuais , Feminino , Humanos , Masculino , Fatores de Proteção , Fatores de Risco , Estados Unidos/epidemiologia
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