212 research outputs found
Regularization dependence of pion generalised parton distributions
Pion generalised parton distributions are calculated within the framework of
the Nambu--Jona-Lasinio model using different regularization schemes, including
the proper time regularization scheme, the three dimensional momentum cutoff
scheme, the four dimensional momentum cutoff scheme, and the Pauli-Villars
regularization scheme. Furthermore, we check the theoretical constraints of
pion generalised parton distributions required by the symmetries of quantum
chromodynamics in different regularization schemes. The diagrams of pion parton
distribution functions are plotted, in addition, we evaluate the Mellin moments
of generalised parton distributions, which related to the electromagnetic and
gravitational form factors of pion. Pion generalised parton distributions are
continuous but not differential at , when considering the effect
of D-term, generalised parton distributions become not continuous at in all the four regularization schemes. Generalised parton distributions
in impact parameter space are considered, the width distribution of quark
in the pion and the mean-squared
are calculated. The light-front transverse-spin distributions are studied, when
quark polarized in the light-front-transverse direction, the
transverse-spin density is no longer symmetric around , the
peaks shift to , we compare the average transverse shift
and in
different regularization schemes. The light-cone energy radius and
the light-cone charge radius are also evaluated, we find that in the
proper time regularization scheme the values of these quantities are the
largest, in the three dimensional momentum cutoff scheme they are the smallest.Comment: 34 pages, 39 figure
Nonclassical photon-pair source based on noiseless photon echo
The Duan-Lukin-Cirac-Zoller (DLCZ) scheme is a potential method to establish
remote entanglements and realize large-scale quantum networks. Here we propose
a DLCZ-like scheme based on the noiseless photon echo in rare-earth ion-doped
crystals. Correlated photon pairs with a controllable delay can be created by
the direct optical rephasing. Theoretical analysis indicates that the protocol
is efficient in the low-optical-depth regime. This protocol could be feasibly
implemented to establish long-lived quantum correlations between a photon and a
spin-wave excitation in rare-earth ion-doped crystals
Hábitos alimenticios de Calanus sinicus (Crustacea: Copepoda) durante primavera y otoño en el mar Bohai, investigados mediante un Ãndice de herbivorÃa
Pigment ingestion rate (PIR) and egg production rate (EPR) of the dominant copepod Calanus sinicus, as well as chlorophyll-a concentration and phytoplankton assemblages were measured in the Bohai Sea, North China in June 1997, October 1998 and May 1999. A herbivore index (H) was also calculated as the carbon specific ratio of PIR and EPR, in order to investigate its feeding habits in the spring and autumn phytoplankton bloom respectively. On average, chlorophyll-a concentration was relatively similar (1-1.34 mg m-3) in the three cruises, but PIR was quite different. It was 3.24 µg C female-1 d-1 in October, equivalent to one half of the PIR for June and one third of the PIR for May. Average EPR was highest in May, and quite similar during the other two months. According to H values, herbivorous feeding contributed 100% of the egg production of C. sinicus in June, 82.5% in May, but only 47.8% in October. It is possible that omnivorous feeding of C. sinicus in October was induced by a prevalence of large-sized diatoms and sufficient non-phytoplankton food resources during the autumn bloom period.La tasa de ingestión de pigmentos (PIR) y la tasa de producción de huevos (EPR) del copépodo dominante Calanus sinicus ha sido determinada, conjuntamente con la concentración de clorofila- a y la composición del fitoplancton, en el mar de Bohai, norte de China, en junio 1997, octubre 1998 y mayo 1999. Para investigar los hábitos alimenticios durante los blooms de fitoplancton de primavera y otoño se ha determinado un Ãndice de herbivorÃa (H), calculado como el cociente de las tasas especÃficas PIR y EPR en carbono. En promedio, la concentración de clorofila-a fue relativamente similar (1-1,34 mg m-3) en las tres campañas oceanográficas. Pero los valores de PIR difirieron bastante, variando desde 3,24 μg C hembra-1 d-1 en octubre a valores un medio y un tercio de dicho valor, respectivamente, en junio y mayo. Los valores promedio de EPR fueron máximos en mayo, y bastante similares durante los otros dos meses. Según los valores del Ãndice H obtenidos, la herbivorÃa contribuyó un 100% en la producción de huevos de C. sinicus en junio y un 82,5% en mayo, mientras que sólo explicó un 47,8% de la producción de huevos en octubre. este estudio sugiere que la alimentación omnivora de C. sinicus en octubre fue inducida por la prevalencia de diatomeas de gran tamaño y la presencia suficiente de alimento no fitoplanctónico durante el periodo del bloom otoñal.
An adolescent with primary cutaneous follicle center lymphoma: a case report and literature review
Primary cutaneous follicle center lymphoma (PCFCL) differs from follicular lymphoma in biological behavior and molecular profile and is treated as a distinct entity, according to the 5th edition of the World Health Organization classification of hematolymphoid tumors. It is an uncommon cutaneous B-cell lymphoma that is considerably rare in children and adolescents. To date, only 13 cases of individuals younger than 20 years of age have been reported in the literature. The lack of relevant clinical epidemiological data in this population has hampered the investigation of its clinical and diagnostic aspects. Here we report the case of a 17-year-old male with PCFCL, who may be the first PCFCL patient under 20 years of age reported in China. He was admitted to the hospital with a solitary nodule on his face. After complete surgical excision, the patient’s facial mass was histologically identified as PCFCL. The patient’s prognosis was favorable, with no recurrence at 17 months of follow-up after the surgical resection. We present a case of an adolescent PCFCL patient and systematically review the literature with a view to increase the awareness of the disease and inform the diagnosis and treatment of this age group
Immune Signatures in Patients with Psoriasis Vulgaris of Blood-Heat Syndrome: A Systematic Review and Meta-Analysis
Objective. To determine whether immunological serum markers IFN-γ, IL-4, IL-17, IL-23, IL-6, TNF-α, and IL-10 are elevated or decreased in patients compared with healthy controls. Methods. A complete search of the literature on this topic within the past 30 years was conducted across seven databases. Seventeen studies including 768 individuals were identified. Differences in serum marker levels between subjects and controls were pooled as MDs using the random-effects model. Results. The pooled MDs were higher in patients than in healthy controls for IFN-γ (MD 24.9, 95% CI 12.36–37.43), IL-17 (MD 28.92, 95% CI 17.44–40.40), IL-23 (MD 310.60, 95% CI 4.96–616.24), and TNF-α (MD 19.84, 95% CI 13.80–25.87). Pooled IL-4 (MD −13.5, 95% CI −17.74–−9.26) and IL-10 (MD −10.33, 95% CI −12.03–−8.63) levels were lower in patients. Conclusion. The pooled analyses suggest that levels of IFN-γ, IL-17, IL-23, and TNF-α are significantly elevated and that levels of IL-4 and IL-10 are significantly decreased in sera of patients with psoriasis vulgaris of blood-heat syndrome. Measuring progression of blood-heat syndrome of psoriasis vulgaris will require additional high-quality data, with a low risk of bias and adequate sample sizes, before and after antipsoriatic therapy
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