1,215 research outputs found
Ovarian cancer initially presenting with isolated ipsilateral superficial inguinal lymph node metastasis: a case study and review of the literature
Isolated superficial inguinal metastases without any extended intra-abdominal spread is a rare event in patients with ovarian carcinoma. Here we report an isolated superficial inguinal metastasis in a patient with primary ovarian cancer. A 54-year-old Chinese patient with primary ovarian cancer, had an isolated painless enlarged right groin swelling (3ร2cm) as the only manifestation, preoperative pathology confirmed metastatic adenocarcinoma. Gynecologic examination, transvaginal ultrasonography of the abdominopelvic cavity revealed a 5-cm mixed, right adnexal mass. At exploratory laparotomy, there was little intra-abdominal tumor dissemination but 100 ml of faint yellow peritoneal fluid and a 5-cm right ovarian tumor with intact capsule. Staging operation was performed and postoperative pathology confirmed adenocarcinoma located within right ovarian, with no evidence of involvement of other sites. Then the patient received adjuvant chemotherapy for Stage IVB. Five years later, the patient is currently still alive without evidence of recurrent disease. This case indicate that ovarian carcinoma isnโt a disease localized only within the intra-peritoneal cavity, isolated superficial inguinal lymph node metastasis might occur in rare cases via potential lymphatic and (or) hematogenous route under special conditions. We propose the need to investigate the possible mechanisms, risk factors, metastatic patterns, the biology and natural history of such patients in a large-scale and multicenter analysis. Furthermore, efforts should be made for earlier and differential diagnosis and finally prolong survival time for such patients
Two-field Models of Dark Energy with Equation of State Across -1
In this paper, we study the possibility of building two-field models of dark
energy with equation of state across -1. Specifically we will consider two
classes of models: one consists of two scalar fields (Quintessence+Phantom) and
another includes one scalar (Phantom) and one spinor field (Neutrino). Our
studies indicate to some extent that two-field models give rise to a simple
realization of the dynamical dark energy model with the equation of state
across .Comment: 5 pages, 4 figures Revtex
Dimensional crossover of thermal conductance in graphene nanoribbons: A first-principles approach
First-principles density-functional calculations are performed to investigate
the thermal transport properties in graphene nanoribbons (GNRs). The
dimensional crossover of thermal conductance from one to two dimensions (2D) is
clearly demonstrated with increasing ribbon width. The thermal conductance of
GNRs in a few nanometer width already exhibits an approximate low-temperature
dependence of , like that of 2D graphene sheet which is attributed to
the quadratic nature of dispersion relation for the out-of-plane acoustic
phonon modes. Using a zone-folding method, we heuristically derive the
dimensional crossover of thermal conductance with the increase of ribbon width.
Combining our calculations with the experimental phonon mean-free path, some
typical values of thermal conductivity at room temperature are estimated for
GNRs and for 2D graphene sheet, respectively. Our findings clarify the issue of
low-temperature dependence of thermal transport in GNRs and suggest a
calibration range of thermal conductivity for experimental measurements in
graphene-based materials.Comment: 18 pages, 4 figure
An Efficient Process for Pretreatment of Lignocelluloses in Functional Ionic Liquids
Background and Aims. The complex structure of the lignocelluloses is the main obstacle in the conversion of lignocellulosic biomass into valuable products. Ionic liquids provide the opportunities for their efficient pretreatment for biomass. Therefore, in this work, pretreatment of corn stalk was carried out in ultrasonic-assisted ionic liquid including 1-butyl-3-methylimidazolium chloride [BMIM]Cl, 1-H-3-methylimidazolium chloride [HMIM]Cl, and 1-(1-propylsulfonic)-3-imidazolium chloride [HSO3-pMIM]Cl at 70ยฐC for 2โh. We compared the pretreatments by ionic liquid with and without the addition of deionized water. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed to analyze the chemical characteristics of regenerated cellulose-rich materials. Results. [HMIM]Cl and [HSO3-pMIM]Cl were effective in lignin extraction to obtain cellulose-rich materials. FTIR analysis and SEM analysis indicated the effective lignin removal and the reduced crystallinity of cellulose-rich materials. Enzymatic hydrolysis of cellulose-rich materials was performed efficiently. High yields of reducing sugar and glucose were obtained when the corn stalk was pretreated by [HMIM]Cl and [HSO3-pMIM]Cl. Conclusions. Ionic liquids provided the ideal environment for lignin extraction and enzymatic hydrolysis of corn stalk and [HMIM]Cl and [HSO3-pMIM]Cl proved the most efficient ionic liquids. This simple and environmentally acceptable method has a great potential for the preparation of bioethanol for industrial production
A Practical Infrastructure for Real-Time Simulation across Timing Domains
A real-time infrastructure, called MLRTI, is proposed in this paper to fulfill the requirement of real-time simulation in distributed environment. There are two novel contributions in this work. Firstly, a flexible timing mechanism is proposed to integrate external time source and local timer utility, enabling the distributed nodes to advance their timeline simultaneously at different speeds with high precision. A data transmission solution is also presented in which the reflective memory card (VMIC) is employed to provide fast data transmission with minimum delay. Secondly, a system partition schema is proposed in MLRTI to reduce the solution errors introduced by transforming a continuous system into distribution system, which is common in a class of control applications where the system is designed in centralized model but simulated in distributed environment for constrains on system structure or the need to balance computation load. Experiments are conducted and the results show this schema effectively reduces the possible errors by properly partitioning the system into parts that are suitable to be deployed in distributed environment
State-dependent Dilatancy Theory and Numerical Modelling of Rockfills
The dilatancy behavior of rockfills is relate to the stress level, the initial state and particle breakage. In this paper, based on the critical state theory, the state-dependent dilatancy theory of rockfills is established, and it is introduced into the state-dependent constitutive model of coarse materials, so the state-dependent constitutive model of rockfills is formulated. According to the large-scale triaxial testing results, using the Fortran program modelling the experimental results, then, comparing the test results and simulation results, only one set parameters of state-dependent constitutive model of rockfills can reflect the strain softening and dilatancy properties of rockfills under the condition of different density, gradation and confining pressure. Therefore, the rationality of the state-dependent constitutive model of rockfills is verified
Equation of motion for multiqubit entanglement in multiple independent noisy channels
We investigate the possibility and conditions to factorize the entanglement
evolution of a multiqubit system passing through multi-sided noisy channels. By
means of a lower bound of concurrence (LBC) as entanglement measure, we derive
an explicit formula of LBC evolution of the N-qubit generalized
Greenberger-Horne-Zeilinger (GGHZ) state under some typical noisy channels,
based on which two kinds of factorizing conditions for the LBC evolution are
presented. In this case, the time-dependent LBC can be determined by a product
of initial LBC of the system and the LBC evolution of a maximally entangled
GGHZ state under the same multi-sided noisy channels. We analyze the realistic
situations where these two kinds of factorizing conditions can be satisfied. In
addition, we also discuss the dependence of entanglement robustness on the
number of the qubits and that of the noisy channels.Comment: 14 page
Anthriscifolcine A, a C18-diterpenoid alkaloid
The title compound, C26H39NO7, which was isolated from Delphinium anthriscifolium var. majus, has a lycoctonine carbon skeleton containing four six-membered rings (A, B, D and E) and three five-membered rings (C, F and G). Rings A, B and E adopt chair conformation, while ring D adopts a boat conformation. Rings C and F adopt envelope conformations
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