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3.
Niger J Clin Pract ; 25(1): 27-32, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35046191

RESUMO

BACKGROUND: The disaster situations call upon the effective and speedy response from the nurses. The link to self-perceived competence in disaster preparedness remains unclear, although there is strong support for competence in nursing practice to ensure safe patient care. AIMS: The study aims to evaluate the self-perceived competence and familiarity of nurses at personal and professional levels concerning disaster preparedness. Cross-sectional exploratory design was employed. A sample of 350 nurses from five government hospitals in Medina was surveyed using an emergency preparedness information questionnaire. PATIENTS AND METHODS: IBM SPSS (Statistical Package for Social Sciences) for Windows, Version 21.0, was used for analyzing the data. RESULTS: Nurses perceived inadequate preparation for emergencies. The unit area had no impact on their self-perceived competence and familiarity. CONCLUSIONS: Female nurses, non-Saudi staff, and years of work experience were perceived to increase nurse competence in disaster preparedness. The managers can create activities to enable nurses to learn and view their disaster preparedness concerns.


Assuntos
Defesa Civil , Planejamento em Desastres , Desastres , Enfermeiras e Enfermeiros , Estudos Transversais , Feminino , Hospitais Públicos , Humanos , Inquéritos e Questionários
4.
J Dent Res ; 100(3): 268-275, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33043768

RESUMO

New strategies for tissue engineering have great potential for restoring and revitalizing impaired tissues and organs, including the use of smart hydrogels that can be modified to enhance organization and functionality of the salivary glands. For instance, monomers of laminin-111 peptides chemically conjugated to fibrin hydrogel (L1pM-FH) promote cell cluster formation in vitro and salivary gland regeneration in vivo when compared with fibrin hydrogel (FH) alone; however, L1pM-FH produce only weak expression of acinar differentiation markers in vivo (e.g., aquaporin-5 and transmembrane protein 16). Since previous studies demonstrated that a greater impact can be achieved when trimeric forms were used as compared with monomeric or dimeric forms, we investigated the extent to which trimers of laminin-111 chemically conjugated to FH (L1pT-FH) can increase the expression of acinar differentiation markers and elevate saliva secretion. In vitro studies using Par-C10 acinar cells demonstrated that when compared with L1pM-FH, L1pT-FH induced similar levels of acinar-like cell clustering, polarization, lumen formation, and calcium signaling. To assess the performance of the trimeric complex in vivo, we compared the ability of L1pM-FH and L1pT-FH to increase acinar differentiation markers and restore saliva flow rate in a salivary gland wound model of C57BL/6 mice. Our results show that L1pT-FH applied to wounded mice significantly improved the expression of the acinar differentiation markers and saliva secretion when compared with the monomeric form. Together, these positive effects of L1pT-FH warrant its future testing in additional models of hyposalivation with the ultimate goal of applying this technology in humans.


Assuntos
Fibrina , Hidrogéis , Animais , Laminina , Camundongos , Camundongos Endogâmicos C57BL , Glândulas Salivares
5.
Oral Dis ; 25(2): 403-415, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29383862

RESUMO

Mice are a widely utilized in vivo model for translational salivary gland research but must be used with caution. Specifically, mouse salivary glands are similar in many ways to human salivary glands (i.e., in terms of their anatomy, histology, and physiology) and are both readily available and relatively easy and affordable to maintain. However, there are some significant differences between the two organisms, and by extension, the salivary glands derived from them must be taken into account for translational studies. The current review details pertinent similarities and differences between human and mouse salivary glands and offers practical guidelines for using both for research purposes.


Assuntos
Glândulas Salivares/anatomia & histologia , Glândulas Salivares/fisiologia , Pesquisa Translacional Biomédica , Animais , Bioengenharia , Técnicas Citológicas , Humanos , Camundongos , Células-Tronco Pluripotentes , Glândulas Salivares/metabolismo , Glândulas Salivares/transplante
6.
J Dent Res ; 96(7): 798-806, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28208029

RESUMO

Hyposalivation contributes to dental caries, periodontitis, and microbial infections. Additionally, it impairs activities of daily living (e.g., speaking, chewing, and swallowing). Treatments for hyposalivation are currently limited to medications (e.g., the muscarinic receptor agonists pilocarpine and cevimeline) that induce saliva secretion from residual acinar cells and the use of saliva substitutes. However, given that these therapies provide only temporary relief, the development of alternative treatments to restore gland function is essential. Previous studies demonstrated that laminin 1 (L1) is critical for intact salivary cell cluster formation and organization. However, the full L1 sequence is not suitable for clinical applications, as each protein domain may contribute to unwanted effects, such as degradation, tumorigenesis, and immune responses that, when compounded, outweigh the potential benefits provided by their sum. Although the L1 peptides YIGSR and A99 linked to fibrin hydrogels (FHs) promote intact salivary epithelial formation in vitro, little is known about their role during salivary gland regeneration in vivo. Therefore, the goal of this study was to demonstrate whether L1 peptides conjugated to FHs promote tissue regeneration in a wound-healing model of mouse submandibular glands (mSMGs). Our results suggest that YIGSR-A99 peptides, chemically conjugated to FHs and applied to wounded mSMGs in vivo, formed new organized salivary tissue. In contrast, wounded mSMGs treated with FHs alone or in the absence of a scaffold showed disorganized collagen formation and poor tissue healing. Together these studies indicate that damaged salivary gland tissue can grow and differentiate when treated with FHs containing L1 peptides.


Assuntos
Fibrina/farmacologia , Hidrogéis/farmacologia , Laminina/farmacologia , Glândula Submandibular/efeitos dos fármacos , Glândula Submandibular/fisiologia , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Modelos Animais de Doenças , Matriz Extracelular/fisiologia , Hidrogéis/síntese química , Camundongos , Microscopia Confocal , Regeneração , Coloração e Rotulagem , Alicerces Teciduais , Cicatrização/efeitos dos fármacos
7.
Eur J Cancer Care (Engl) ; 26(4): e12555, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27434998

RESUMO

This research aimed to describe changes in symptom occurrence and severity of the 31 symptoms during the chemotherapy cycle at three time points. This descriptive, longitudinal study investigated Saudi children who underwent a cycle of chemotherapy (n = 132) in four tertiary hospitals. The Arabic version of the Memorial Symptom Assessment Scale, Karnofsky Performance Status and a demographic questionnaire were used. More than 30% of children reported 10 or more symptoms during the cycle. Symptom occurrence trajectories were analysed using multilevel logistic regression. Six symptoms (i.e. fatigue, sadness, irritability, worrying, weight loss, sweating) showed a decreasing linear trend. Significant quadratic patterns of change were found for feeling drowsy, nausea and vomiting. No significant differences, over time were found in any of the symptom severity scores by using multilevel negative binomial regression. This study is the first to examine the trajectory of multiple symptoms that children experience during a cycle of chemotherapy in Saudi Arabia. Children in this study reported a high number of symptoms across the entire cycle of chemotherapy. Intervention studies are needed to improve care for these symptoms.

8.
Oral Dis ; 23(5): 576-597, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27426637

RESUMO

Lipid mediators (LM) of inflammation are a class of compounds derived from ω-3 and ω-6 fatty acids that play a wide role in modulating inflammatory responses. Some LM possess pro-inflammatory properties, while others possess proresolving characteristics, and the class switch from pro-inflammatory to proresolving is crucial for tissue homeostasis. In this article, we review the major classes of LM, focusing on their biosynthesis and signaling pathways, and their role in systemic and, especially, oral health and disease. We discuss the detection of these LM in various body fluids, focusing on diagnostic and therapeutic applications. We also present data showing gender-related differences in salivary LM levels in healthy controls, leading to a hypothesis on the etiology of inflammatory diseases, particularly Sjögren's syndrome. We conclude by enumerating open areas of research where further investigation of LM is likely to result in therapeutic and diagnostic advances.


Assuntos
Líquidos Corporais/metabolismo , Eicosanoides/metabolismo , Mediadores da Inflamação/metabolismo , Doenças da Boca/metabolismo , Animais , Eicosanoides/biossíntese , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/metabolismo , Humanos , Inflamação/metabolismo , Leucotrienos/biossíntese , Leucotrienos/metabolismo , Lipoxinas , Prostaglandinas/biossíntese , Prostaglandinas/metabolismo , Transdução de Sinais
9.
J Dent Res ; 94(11): 1610-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26285810

RESUMO

Saliva plays a major role in maintaining oral health. Patients with salivary hypofunction exhibit difficulty in chewing and swallowing foods, tooth decay, periodontal disease, and microbial infections. At this time, treatments for hyposalivation are limited to medications (e.g., muscarinic receptor agonists: pilocarpine and cevimeline) that induce saliva secretion from residual acinar cells as well as artificial salivary substitutes. Therefore, advancement of restorative treatments is necessary to improve the quality of life in these patients. Our previous studies indicated that salivary cells are able to form polarized 3-dimensional structures when grown on growth factor-reduced Matrigel. This basement membrane is rich in laminin-III (L1), which plays a critical role in salivary gland formation. Mitotically inactive feeder layers have been used previously to support the growth of many different cell types, as they provide factors necessary for cell growth and organization. The goal of this study was to improve salivary gland cell differentiation in primary cultures by using a combination of L1 and a feeder layer of human hair follicle-derived mesenchymal stem cells (hHF-MSCs). Our results indicated that the direct contact of mouse submandibular (mSMG) cell clusters and hHF-MSCs was not required for mSMG cells to form acinar and ductal structures. However, the hHF-MSC conditioned medium enhanced cell organization and multilumen formation, indicating that soluble signals secreted by hHF-MSCs play a role in promoting these features.


Assuntos
Células-Tronco Mesenquimais/citologia , Glândulas Salivares/citologia , Animais , Aquaporina 5/fisiologia , Diferenciação Celular/fisiologia , Feminino , Folículo Piloso/citologia , Humanos , Laminina/fisiologia , Células-Tronco Mesenquimais/fisiologia , Camundongos Endogâmicos C57BL , Ductos Salivares/citologia , Ductos Salivares/crescimento & desenvolvimento , Glândulas Salivares/crescimento & desenvolvimento , Glândula Submandibular/citologia , Glândula Submandibular/fisiologia , Engenharia Tecidual/métodos
10.
J Dent Res ; 94(2): 312-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25403566

RESUMO

NFIB (nuclear factor I B) is a NFI transcription factor family member, which is essential for the development of a variety of organ systems. Salivary gland development occurs through several stages, including prebud, bud, pseudoglandular, canalicular, and terminal. Although many studies have been done to understand mouse submandibular gland (SMG) branching morphogenesis, little is known about SMG cell differentiation during the terminal stages. The goal of this study was to determine the role of NFIB during SMG development. We analyzed SMGs from wild-type and Nfib-deficient mice (Nfib (-/-)). At embryonic (E) day 18.5, SMGs from wild-type mice showed duct branching morphogenesis and differentiation of tubule ductal cells into tubule secretory cells. In contrast, SMGs from Nfib (-/-) mice at E18.5 failed to differentiate into tubule secretory cells while branching morphogenesis was unaffected. SMGs from wild-type mice at E16.5 displayed well-organized cuboidal inner terminal tubule cells. However, SMGs from Nfib (-/-) at E16.5 displayed disorganized inner terminal tubule cells. SMGs from wild-type mice at E18.5 became fully differentiated, as indicated by a high degree of apicobasal polarization (i.e., presence of apical ZO-1 and basolateral E-cadherin) and columnar shape. Furthermore, SMGs from wild-type mice at E18.5 expressed the protein SMGC, a marker for tubule secretory cells. However, SMGs from Nfib (-/-) mice at E18.5 showed apicobasal polarity, but they were disorganized and lost the ability to secrete SMGC. These findings indicate that the transcription factor NFIB is not required for branching morphogenesis but plays a key role in tubule cell differentiation during mouse SMG development.


Assuntos
Fatores de Transcrição NFI/fisiologia , Glândula Submandibular/embriologia , Animais , Aquaporina 5/análise , Biomarcadores/análise , Caderinas/análise , Diferenciação Celular/fisiologia , Polaridade Celular/fisiologia , Forma Celular , Desenvolvimento Embrionário , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Morfogênese/fisiologia , Mucinas/análise , Fatores de Transcrição NFI/genética , Ductos Salivares/citologia , Ductos Salivares/embriologia , Glândula Submandibular/citologia , Proteína da Zônula de Oclusão-1/análise
11.
Phys Rev Lett ; 112(18): 182501, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24856691

RESUMO

The study of exclusive π(±) electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=σL(π-)/σL(π+) is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=σT(π-)/σT(π+) from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π(±) electroproduction on the deuteron at central Q(2) values of 0.6, 1.0, 1.6 GeV(2) at W=1.95 GeV, and Q(2)=2.45 GeV(2) at W=2.22 GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.

12.
Adv Dent Res ; 26(1): 7-14, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24736699

RESUMO

Adequate salivary secretion is crucial to both oral and general health, since it provides a complex milieu for support of the microbial populations of the mouth, while at the same time containing antimicrobial products that help control these microbial populations. This paper summarizes several aspects of salivary component function, gland secretion mechanisms, and immunopathogenesis as related to oral health and disease. Salivary components mediate microbial attachment to oral surfaces, and also interact with planktonic microbial surfaces to facilitate agglutination and elimination of pathogens from the oral cavity. Adhesive interactions are often mediated by lectin-like bacterial proteins that bind to glycan motifs on salivary glycoproteins. An important salivary antimicrobial protein is histatin 5 (Hst 5), which shows potent and selective antifungal activity and also susceptibility to proteolytic degradation. Coupling of Hst 5 with the carrier molecule spermidine significantly enhanced killing of C. albicans and resistance to proteolytic degradation, compared with the parent peptide. Loss of salivary secretion may be caused by disorders such as Sjögren's syndrome (SS) or ectodermal dysplasia, or may be a side-effect of radiation therapy. Two new approaches to the treatment of salivary gland dysfunction include the use of resolvins and the creation of differentiated acinar structures to construct an artificial salivary gland. B-cells contribute to the pathogenesis of SS by releasing cytokines and autoantibodies and by influencing T-cell differentiation. CXCL13, a potent B-cell chemokine associated with autoimmune diseases, is elevated locally and systemically in SS and may represent a novel biomarker or therapeutic target in the management and treatment of SS.


Assuntos
Saliva/microbiologia , Glândulas Salivares/fisiopatologia , Candida albicans/metabolismo , Candidíase/tratamento farmacológico , Histatinas/metabolismo , Humanos , Proteoma
13.
J Dent Res ; 93(3): 300-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24389810

RESUMO

Resolvins are potent anti-inflammatory mediators derived from ω-3 fatty acids. Results from our previous studies indicated that resolvin D1 (RvD1) blocks pro-inflammatory responses in salivary glands. Furthermore, RvD1 enhances salivary epithelial integrity, demonstrating its potential use for the restoration of salivary gland function in Sjögren's syndrome (SS). We investigated whether the RvD1 biosynthetic machinery (e.g., cytosolic phospholipase A2, calcium-independent phospholipase A2, 12/15 and 5-lipoxygenase) is expressed in mouse submandibular glands (mSMG), using qPCR and Western blot analyses. Additionally, we determined the localization of RvD1 biosynthetic machinery in mSMG and human minor salivary glands (hMSG), with and without SS, using confocal microscopy. Finally, we measured RvD1 levels in cell supernatants from mSMG cell cultures and freshly isolated mSMG cells, with and without SS, using ELISA. Our results indicate that: (1) RvD1 machinery is expressed in mouse and human salivary glands; (2) polar distribution of RvD1 biosynthetic machinery is lost in hMSG with SS; (3) RvD1 levels in mSMG cell culture supernatants increased with time; and (4) RvD1 levels in mSMG cell supernatants, with and without SS, were similar. These studies demonstrate that the RvD1 biosynthesis machinery is expressed and functional in salivary glands with and without SS.


Assuntos
Ácidos Docosa-Hexaenoicos/biossíntese , Glândula Submandibular/metabolismo , Animais , Araquidonato 12-Lipoxigenase/análise , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/análise , Araquidonato 15-Lipoxigenase/metabolismo , Araquidonato 5-Lipoxigenase/análise , Araquidonato 5-Lipoxigenase/metabolismo , Técnicas de Cultura de Células , Membrana Celular/enzimologia , Células Cultivadas , Citosol/enzimologia , Ácidos Docosa-Hexaenoicos/análise , Epitélio/metabolismo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Endogâmicos , Fosfolipases A2 Independentes de Cálcio/análise , Fosfolipases A2 Independentes de Cálcio/metabolismo , Fosfolipases A2 Citosólicas/análise , Fosfolipases A2 Citosólicas/metabolismo , Glândulas Salivares Menores/metabolismo , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/patologia , Glândula Submandibular/citologia
14.
Phys Rev Lett ; 110(1): 012502, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23383783

RESUMO

An experiment with a newly developed high-resolution kaon spectrometer and a scattered electron spectrometer with a novel configuration was performed in Hall C at Jefferson Lab. The ground state of a neutron-rich hypernucleus, (Λ)(7)He, was observed for the first time with the (e, e'K+) reaction with an energy resolution of ~0.6 MeV. This resolution is the best reported to date for hypernuclear reaction spectroscopy. The (Λ)(7)He binding energy supplies the last missing information of the A = 7, T = 1 hypernuclear isotriplet, providing a new input for the charge symmetry breaking effect of the ΛN potential.

15.
Oral Dis ; 19(3): 236-44, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22805753

RESUMO

Oral Diseases (2013) 19, 236-244 Saliva plays a major role in maintaining oral health. Patients afflicted with a decrease in saliva secretion (symptomatically, xerostomia) exhibit difficulty in chewing and swallowing foods, tooth decay, periodontal disease, and microbial infections. Despite recent improvements in treating xerostomia (e.g., saliva stimulants, saliva substitutes, and gene therapy), there is a need of more scientific advancements that can be clinically applied toward restoration of compromised salivary gland function. Here we provide a summary of the current salivary cell models that have been used to advance restorative treatments via development of an artificial salivary gland. These models represent initial steps toward clinical and translational research, to facilitate creation of clinically safe salivary glands. Further studies in salivary cell lines and primary cells are necessary to improve survival rates, cell differentiation, and secretory function. Additionally, the characterization of salivary progenitor and stem cell markers are necessary. Although these models are not fully characterized, their improvement may lead to the construction of an artificial salivary gland that is in high demand for improving the quality of life of many patients suffering from salivary secretory dysfunction.


Assuntos
Engenharia Celular , Modelos Biológicos , Glândulas Salivares , Engenharia Celular/métodos , Linhagem Celular Tumoral , Humanos , Células-Tronco
16.
Mucosal Immunol ; 4(4): 448-55, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21346738

RESUMO

Oropharyngeal candidiasis (OPC, thrush) is an opportunistic infection caused by the commensal fungus Candida albicans. An understanding of immunity to Candida has recently begun to unfold with the identification of fungal pattern-recognition receptors such as C-type lectin receptors, which trigger protective T-helper (Th)17 responses in the mucosa. Hyper-IgE syndrome (HIES/Job's syndrome) is a rare congenital immunodeficiency characterized by dominant-negative mutations in signal transducer and activator of transcription 3, which is downstream of the Th17-inductive cytokines interleukin (IL)-6 and IL-23, and hence patients with HIES exhibit dramatic Th17 deficits. HIES patients develop oral and mucocutaneous candidiasis, supporting a protective role for Th17 cells in immunity to OPC. However, the Th17-dependent mechanisms of antifungal immunity in OPC are still poorly defined. An often unappreciated aspect of oral immunity is saliva, which is rich in antimicrobial proteins (AMPs) and exerts direct antifungal activity. In this study, we show that HIES patients show significant impairment in salivary AMPs, including ß-defensin 2 and Histatins. This tightly correlates with reduced candidacidal activity of saliva and concomitantly elevated colonization with Candida. Moreover, IL-17 induces histatins in cultured salivary gland cells. This is the first demonstration that HIES is associated with defective salivary activity, and provides a mechanism for the severe susceptibility of these patients to OPC.


Assuntos
Candidíase/complicações , Candidíase/imunologia , Síndrome de Job/complicações , Síndrome de Job/imunologia , Mucosa Bucal/imunologia , Mucosa Bucal/microbiologia , Monofosfato de Adenosina/imunologia , Monofosfato de Adenosina/metabolismo , Adolescente , Adulto , Candida albicans/imunologia , Criança , Feminino , Regulação da Expressão Gênica/imunologia , Histatinas/imunologia , Histatinas/metabolismo , Humanos , Imunidade nas Mucosas , Masculino , Pessoa de Meia-Idade , Saliva/imunologia , Células Th17/imunologia , Células Th17/metabolismo , Adulto Jovem , beta-Defensinas/imunologia , beta-Defensinas/metabolismo
17.
Phys Rev Lett ; 101(12): 120401, 2008 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-18851343

RESUMO

We report on the first results of a sensitive search for scalar coupling of photons to a light neutral boson in the mass range of approximately 1.0 meV (milli-electron volts) and coupling strength greater than 10(-6) GeV(-1) using optical photons. This was a photon regeneration experiment using the "light shining through a wall" technique in which laser light was passed through a strong magnetic field upstream of an optical beam dump; regenerated laser light was then searched for downstream of a second magnetic field region optically shielded from the former. Our results show no evidence for scalar coupling in this region of parameter space.

18.
Phys Rev Lett ; 98(14): 142301, 2007 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-17501267

RESUMO

We report on a study of the longitudinal to transverse cross section ratio, R=sigmaL/sigmaT, at low values of x and Q2, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Laboratory Hall C spanning the four-momentum transfer range 0.06

19.
Phys Rev Lett ; 98(2): 022001, 2007 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-17358596

RESUMO

A large data set of charged-pion (pi+/-) electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-->pion production mechanisms.

20.
Phys Rev Lett ; 94(14): 142301, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15904058

RESUMO

We report the results of a new Rosenbluth measurement of the proton electromagnetic form factors at Q2 values of 2.64, 3.20, and 4.10 GeV2. Cross sections were determined by detecting the recoiling proton, in contrast to previous measurements which detected the scattered electron. Cross sections were determined to 3%, with relative uncertainties below 1%. The ratio mu(p)G(E)/G(M) was determined to 4%-8% and showed mu(p)G(E)/G(M) approximately 1. These results are consistent with, and much more precise than, previous Rosenbluth extractions. They are inconsistent with recent polarization transfer measurements of similar precision, implying a systematic difference between the techniques.

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