546 research outputs found
Connection of four-dimensional Langevin model and Hauser-Feshbach theory to describe statistical decay of fission fragments
We developed a method superposing two different fission modes calculated in a
four-dimensional Langevin model to obtain more accurate fission fragment yield
and total kinetic energy (TKE). The two fission modes correspond to the
standard I and standard II modes reported by Brosa et al., and parameters in
the Langevin model and the superposing ratio were determined to reproduce the
fission fragment yield of Pu of spontaneous fission. We also
investigated the fission fragment yields and the TKEs of other Pu isotopes by
using the same Langevin parameters and different superposing ratios, such as
spontaneous fission of Pu and neutron-induced fission of
Pu. The prompt fission observables, such as the neutron multiplicity,
the prompt fission neutron spectrum, and the independent fission product yield
were calculated in the Hauser-Feshbach statistical decay model implemented in a
nuclear reaction code TALYS with Pu(n,f) in the incident energies
ranging from thermal energy up to 5 MeV. The calculated fission observables
qualitatively reproduce several known trends while calculated results have
quantitative discrepancies between reported data. Although more improvements
are needed for the most important nuclides, it turned out that our approach has
the capability to provide prompt fission observables for difficult-to-measure
nuclides.Comment: 19 pages, 10 figures, Under review in Journal of Nuclear Science and
Technolog
Primary strumal carcinoid tumor of the ovary: A pregnant patient exhibiting severe constipation and CEA elevation
► We present a rare case of a PYY-positive primary strumal carcinoid tumor of the ovary during pregnancy. ► MRI was useful for the preoperative diagnosis, and the prenatal course was uneventful after the operation. ► Colitis due to severe constipation caused by PYY, which is an inhibitor of intestinal mobility, might induce serum CEA elevation
Spin-Correlation Coefficients and Phase-Shift Analysis for p+He Elastic Scattering
Angular Distributions for the target spin-dependent observables A,
A, and A have been measured using polarized proton beams at
several energies between 2 and 6 MeV and a spin-exchange optical pumping
polarized He target. These measurements have been included in a global
phase-shift analysis following that of George and Knutson, who reported two
best-fit phase-shift solutions to the previous global p+He elastic
scattering database below 12 MeV. These new measurements, along with
measurements of cross-section and beam-analyzing power made over a similar
energy range by Fisher \textit{et al.}, allowed a single, unique solution to be
obtained. The new measurements and phase-shifts are compared with theoretical
calculations using realistic nucleon-nucleon potential models.Comment: Submitted to Phys. Rev.
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Divergent drivers of leaf trait variation within species, among species, and among functional groups.
Understanding variation in leaf functional traits-including rates of photosynthesis and respiration and concentrations of nitrogen and phosphorus-is a fundamental challenge in plant ecophysiology. When expressed per unit leaf area, these traits typically increase with leaf mass per area (LMA) within species but are roughly independent of LMA across the global flora. LMA is determined by mass components with different biological functions, including photosynthetic mass that largely determines metabolic rates and contains most nitrogen and phosphorus, and structural mass that affects toughness and leaf lifespan (LL). A possible explanation for the contrasting trait relationships is that most LMA variation within species is associated with variation in photosynthetic mass, whereas most LMA variation across the global flora is associated with variation in structural mass. This hypothesis leads to the predictions that (i) gas exchange rates and nutrient concentrations per unit leaf area should increase strongly with LMA across species assemblages with low LL variance but should increase weakly with LMA across species assemblages with high LL variance and that (ii) controlling for LL variation should increase the strength of the above LMA relationships. We present analyses of intra- and interspecific trait variation from three tropical forest sites and interspecific analyses within functional groups in a global dataset that are consistent with the above predictions. Our analysis suggests that the qualitatively different trait relationships exhibited by different leaf assemblages can be understood by considering the degree to which photosynthetic and structural mass components contribute to LMA variation in a given assemblage
Choriocarcinoma coexisting with epithelioid trophoblastic tumor of the uterine horn
• We report a choriocarcinoma coexisting with an epithelioid trophoblastic tumor. • Chemotherapy with methotrexate, etoposide, and actinomycin-D was efficacious. • Choriocarcinoma with epithelioid trophoblastic tumor may benefit from chemotherapy
Spontaneous Rupture of an Unscarred Gravid Uterus in a Primigravid Woman at 32 Weeks of Gestation
Uterine rupture usually occurs in a scarred uterus, especially secondary to prior cesarean section. Antepartum uterine rupture in an unscarred uterus is extremely rare. We report a case of spontaneous rupture of an unscarred gravid uterus at 32 weeks of gestation in a primigravid woman. Ultrasonography and magnetic resonance imaging showed a bulging cystic lesion communicating with the intrauterine cavity. Operative findings during emergent cesarean section revealed uterine perforation in the right cornual area and a prolapsed, nonbleeding amniotic sac. The left cornual area was also focally thin. An arcuate uterus was suspected based on follow-up hysterosalpingography. Antepartum uterine rupture tends to occur in the uterine cornual area. In this case, Müllerian duct anomalies may have been associated with focal myometrial defects
Clear cell sarcoma of the soft parts arising in the rectus abdominis in a child – aspiration cytology of a rare case
<p>Abstract</p> <p>Background</p> <p>Clear cell sarcoma of soft parts is most commonly found associated with the tendons and aponeuroses of distal extremities in young adults with a peak incidence in the third decade. Location in the abdominal wall and in a child is very rare.</p> <p>Case presentation</p> <p>A nine-year-old female child presented with a swelling in the anterior abdominal wall in the suprapubic region. Fine needle aspiration revealed predominantly discrete cells with loose clustering at places. The cytoplasm was abundant, finely granular, and eosinophilic with some cells exhibiting clear vacuolated zones. No pigment was seen. The nuclei were rounded and eccentrically placed with a striking single eosinophilic macro nucleolus present in all the cells. Taking into consideration, the history, age of the patient, location of the tumor and absence of melanin pigment, a diagnosis of soft tissue sarcoma was made, the differential including Clear cell sarcoma. This was subsequently confirmed on histopathological examination and immunohistochemistry</p> <p>Conclusion</p> <p>The atypical presentation of the case made the cytological diagnosis rather challenging. Clear cell sarcoma should be considered when cytology of a soft-tissue tumor shows uncharacteristically high cellularity and relatively uniform cells with macronucleoli.</p
Classifications of ovarian cancer tissues by proteomic patterns
Ovarian cancer is a morphologically and biologically heterogeneous disease. The identification of type-specific protein markers for ovarian cancer would provide the basis for more tailored treatments, as well as clues for understanding the molecular mechanisms governing cancer progression. In the present study, we used a novel approach to classify 24 14ovarian cancer tissue samples based on the proteomic pattern of each sample. The method involved fractionation according to p I using chromatofocusing with analytical columns in the first dimension followed by separation of the proteins in each p I fraction using nonporous RP 14HPLC, which was coupled to an ESI-TOF mass analyzer for molecular weight 14(MW) analysis. A 2-D mass map of the protein content of each type of ovarian cancer tissue samples based upon p I versus intact protein MW was generated. Using this method, the clear cell and serous ovarian carcinoma samples were histologically distinguished by principal component analysis and clustering analysis based on their protein expression profiles and subtype-specific biomarker candidates of ovarian cancers were identified, which could be further investigated for future clinical study.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55853/1/5846_ftp.pd
Effectiveness of adjuvant systemic chemotherapy for intermediate-risk stage IB cervical cancer
Objective: To examine the effectiveness of systemic chemotherapy following radical hysterectomy for women with intermediate-risk stage IB cervical cancer.Materials and Methods: This is a retrospective analysis of a previously organized nation-wide cohort study examining 6,003 women with stage IB-IIB cervical cancer who underwent radical hysterectomy between 2004 and 2008 in Japan. Survival of 555 women with stage IB cervical cancer in the intermediate-risk group (deep stromal invasion > 50%, large tumor size > 4 cm, and lympho-vascular space invasion [LVSI]) were examined based on adjuvant therapy patterns: chemotherapy alone (n = 223, 40.2%), concurrent chemo-radiotherapy (n = 172, 31.0%), and radiotherapy alone (n = 160, 28.8%).Results: The most common intermediate-risk pattern was LVSI with deep stromal invasion (n = 216, 38.5%). The most common chemotherapeutic choice was taxane/platinum (52.2%). Women with adenocarcinoma/adenosquamous histology were more likely to receive chemotherapy (P = 0.03), and intermediate-risk pattern was not associated with chemotherapy use (P = 0.11). Women who received systemic chemotherapy had disease-free survival (5-year rate, 88.1% versus 90.2%, adjusted-hazard ratio (HR) 0.98, 95% confidence interval (CI) 0.52–1.83, P = 0.94) and cause-specific survival (95.4% versus 94.8%, adjusted-HR 0.85, 95% CI 0.34–2.07, P = 0.71) similar to those who received concurrent chemo-radiotherapy on multivariable analysis. Similar results were seen among 329 women with multiple intermediate-risk factors (5-year rates for disease-free survival, chemotherapy versus concurrent chemo-radiotherapy, 87.1% versus 90.2%, P = 0.86; and cause-specific survival 94.6% versus 93.4%, P = 0.82). Cumulative local-recurrence (P = 0.77) and distant-recurrence (P = 0.94) risks were similar across the adjuvant therapy types.Conclusions: Our study suggests that systemic chemotherapy may be an alternative treatment choice for adjuvant therapy in intermediate-risk stage IB cervical cancer
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