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In this work, we present new data on the $^{182,183,184}$W($\gamma,n$) cross sections, utilizing a quasi-monochromatic photon beam produced at the NewSUBARU synchrotron radiation facility. Further, we have extracted the nuclear level density and $\gamma$-ray strength function of $^{186}$W from data on the $^{186}$W($\alpha,\alpha^\prime\gamma$)$^{186}$W reaction measured at the Oslo Cyclotron Laboratory. Combining previous measurements on the $^{186}$W($\gamma,n$) cross section with our new $^{182,183,184}$W($\gamma,n$) and ($\alpha,\alpha^\prime\gamma$)$^{186}$W data sets, we have deduced the $^{186}$W $\gamma$-ray strength function in the range of $1 < E_\gamma < 6$ MeV and $7 < E_\gamma < 14$ MeV. Our data are used to extract the level density and $\gamma$-ray strength functions needed as input to the nuclear-reaction code \textsf{TALYS}, providing an indirect, experimental constraint for the $^{185}$W($n,\gamma$)$^{186}$W cross section and reaction rate. Compared to the recommended Maxwellian-averaged cross section (MACS) in the KADoNiS-1.0 data base, our results are on average lower for the relevant energy range $k_B T \in [5,100]$ keV, and we provide a smaller uncertainty for the MACS. The theoretical values of Bao \textit{et al.} and the cross section experimentally constrained on photoneutron data of Sonnabend \textit{et al.} are significantly higher than our result. The lower value by Mohr \textit{et al.} is in very good agreement with our deduced MACS. Our new results could have implications for the $s$-process and in particular the predicted $s$-process production of $^{186,187}$Os nuclei., Comment: 17 pages, 15 figures; to be submitted to Phys. Rev. C

In this work, we present new data on the $^{182,183,184}$W($γ,n$) cross sections, utilizing a quasi-monochromatic photon beam produced at the NewSUBARU synchrotron radiation facility. Further, we have extracted the nuclear level density and $γ$-ray strength function of $^{186}$W from data on the $^{186}$W($α,α^\primeγ$)$^{186}$W reaction measured at the Oslo Cyclotron Laboratory. Combining previous measurements on the $^{186}$W($γ,n$) cross section with our new $^{182,183,184}$W($γ,n$) and ($α,α^\primeγ$)$^{186}$W data sets, we have deduced the $^{186}$W $γ$-ray strength function in the range of $1 < E_γ< 6$ MeV and $7 < E_γ< 14$ MeV. Our data are used to extract the level density and $γ$-ray strength functions needed as input to the nuclear-reaction code \textsf{TALYS}, providing an indirect, experimental constraint for the $^{185}$W($n,γ$)$^{186}$W cross section and reaction rate. Compared to the recommended Maxwellian-averaged cross section (MACS) in the KADoNiS-1.0 data base, our results are on average lower for the relevant energy range $k_B T \in [5,100]$ keV, and we provide a smaller uncertainty for the MACS. The theoretical values of Bao \textit{et al.} and the cross section experimentally constrained on photoneutron data of Sonnabend \textit{et al.} are significantly higher than our result. The lower value by Mohr \textit{et al.} is in very good agreement with our deduced MACS. Our new results could have implications for the $s$-process and in particular the predicted $s$-process production of $^{186,187}$Os nuclei., 17 pages, 15 figures; to be submitted to Phys. Rev. C

The experimental gamma-ray strength functions (gamma-SFs) of 142,144-151Nd have been studied for gamma-ray energies up to the neutron separation energy. The results represent a unique set of gamma-SFs for an isotopic chain with increasing nuclear deformation. The data reveal how the low-energy enhancement, the scissors mode and the pygmy dipole resonance evolve with nuclear deformation and mass number. The data indicate that the mechanisms behind the low-energy enhancement and the scissors mode are decoupled from each other., 14 pages and 10 figures

Understanding the evolution of level densities in the crossover from spherical to well-deformed nuclei has been a long-standing problem in nuclear physics. We measure nuclear level densities for a chain of neodymium isotopes Nd-142,Nd-144-151 which exhibit such a crossover. These results represent the most complete data set of nuclear level densities to date for an isotopic chain between neutron shell-closure and towards mid-shell. We observe a strong increase of the level densities along the chain with an overall increase by a factor of approximate to 150at an excitation energy of 6 MeV and saturation around mass 150. Level densities calculated by the shell model Monte Carlo (SMMC) are in excellent agreement with these experimental results. Based on our experimental and theoretical findings, we offer an explanation of the observed mass dependence of the level densities in terms of the intrinsic single-particle level density and the collective enhancement. (C) 2021 The Author(s). Published by Elsevier B.V.

ALBA-CELLS;American Physical Society Division of Physics of Beams (APS-DPB);Asian Committee for Future Accelerators (ACFA);ASTeC/STFC;Centro Fermi;et al., 5th International Particle Accelerator Conference, IPAC 2014 -- 15 June 2014 through 20 June 2014 -- -- 111842, Turkish Accelerator Center (TAC) Project has started with support of the Ministry of Development (MD) of Turkey under the coordination of Ankara University. TAC is an inter-university collaboration with 12 Turkish Universities. An IR FEL facility (TARLA) based on Sc linac with 15-40 MeV energy under construction in Ankara as the first facility of TAC. It is expected that the TARLA facility will be commissioned in 2017. In addition to the TARLA, it is planned that Turkish Accelerator Center will include a third generation synchrotron radiation facility based on 3 GeV electron synchrotron (TAC SR), a fourth generation SASE FEL facility based on 3 GeV electron linac (TAC SASE FEL), a multi-purpose proton accelerator facility with 3 MeV - 2 GeV beam energy (TAC PAF) and an electron-positron collider as a super charm factory (TAC PF) Construction phase of the proposed GeV scale accelerator facilities will cover next decades. In this presentation, main goals and road map of Turkish Accelerator Center will be explained. Copyright © 2014 CC-BY-3.0 and by the respective authors.

Background: We examined the impact of adjuvant modalities on resected pancreatic and periampullary adenocarcinoma (PAC). Methods: A total of 563 patients who were curatively resected for PAC were retrospectively analyzed between 2003 and 2013. Results: Of 563 patients, 472 received adjuvant chemotherapy (CT) alone, chemoradiotherapy (CRT) alone, and chemoradiotherapy plus chemotherapy (CRT-CT) were analyzed. Of the 472 patients, 231 were given CRT-CT, 26 were given CRT, and 215 were given CT. The median recurrence-free survival (RFS) and overall survival (OS) were 12 and 19 months, respectively. When CT and CRT-CT groups were compared, there was no significant difference with respect to both RFS and OS, and also there was no difference in RFS and OS among CRT-CT, CT and CRT groups. To further investigate the impact of radiation on subgroups, patients were stratified according to lymph node status and resection margins. In node-positive patients, both RFS and OS were significantly longer in CRT-CT than CT. In contrast, there was no significant difference between groups when patients with node-negative disease or patients with or without positive surgical margins were considered. Conclusions: Addition of radiation to CT has a survival benefit in patients with node-positive disease following pancreatic resection.

ALBA-CELLS;American Physical Society Division of Physics of Beams (APS-DPB);Asian Committee for Future Accelerators (ACFA);ASTeC/STFC;Centro Fermi;et al., 5th International Particle Accelerator Conference, IPAC 2014 -- 15 June 2014 through 20 June 2014 -- -- 111842, Turkish Accelerator Center (TAC) Project has started with support of the Ministry of Development (MD) of Turkey under the coordination of Ankara University. TAC is an inter-university collaboration with 12 Turkish Universities. An IR FEL facility (TARLA) based on Sc linac with 15-40 MeV energy under construction in Ankara as the first facility of TAC. It is expected that the TARLA facility will be commissioned in 2017. In addition to the TARLA, it is planned that Turkish Accelerator Center will include a third generation synchrotron radiation facility based on 3 GeV electron synchrotron (TAC SR), a fourth generation SASE FEL facility based on 3 GeV electron linac (TAC SASE FEL), a multi-purpose proton accelerator facility with 3 MeV - 2 GeV beam energy (TAC PAF) and an electron-positron collider as a super charm factory (TAC PF) Construction phase of the proposed GeV scale accelerator facilities will cover next decades. In this presentation, main goals and road map of Turkish Accelerator Center will be explained. Copyright © 2014 CC-BY-3.0 and by the respective authors.

The development of brain metastases (BMs) was associated with poor prognosis in melanoma patients. Patients with BMs have a median survival of < 6 months. Melanoma is the third most common tumor to metastasize to the brain with a reported incidence of 10-40 %. Our aim was to identify factors predicting development of BMs and survival. We performed a retrospective analysis of 470 melanoma patients between 2000 and 2012. The logistic regression analyses were used to identify the clinicopathological features of primary melanoma that are predictive of BMs development and survival after a diagnosis of brain metastases. There were 52 patients (11.1 %) who developed melanoma BMs during the study period. The analysis of post-BMs with Kaplan-Meier curves has resulted in a median survival rate of 4.1 months (range 2.9-5.1 months). On logistic regression analysis site of the primary tumor on the head and neck (p = 0.002), primary tumor thickness (Breslow > 4 mm) (p = 0.008), ulceration (p = 0.007), and pathologically N2 and N3 diseases (p = 0.001) were found to be significantly associated with the development of BMs. In univariate analysis, tumor thickness and performance status had a significant influence on post-BMs survival. In multivariate analysis, these clinicopathologic factors were not remained as significant predictive factors. Our results revealed the importance of primary tumor characteristics associated with the development of BMs. Ulceration, primary tumor thickness, anatomic site, and pathologic a parts per thousand yenN2 disease were found to be significant predictors of BMs development.

ALBA-CELLS;American Physical Society Division of Physics of Beams (APS-DPB);Asian Committee for Future Accelerators (ACFA);ASTeC/STFC;Centro Fermi;et al., 5th International Particle Accelerator Conference, IPAC 2014 -- 15 June 2014 through 20 June 2014 -- -- 111842, The Turkish Accelerator Center Proton Accelerator Facility (TAC PAF) is based on a 1 MW and 2-GeV proton linac that will include both normal conducting and superconducting accelerator structures. The normal conducting part of the TAC PAF will consist of an ion source, a low energy beam transport line, a radio frequency quadrupole, a medium energy beam transport line, and two drift tube linac structures in order to accelerate the beam up to 65 MeV. Acceleration from 65 MeV up to 2-GeV energy will be provided by a SC-spoke cavity and two SC-elliptical cavities. In the long term, TAC PAF will be used as a neutron source. We report the current status of the project including accelerator structures, ion source studies, and possible experimental stations. Copyright © 2014 CC-BY-3.0 and by the respective authors.

Purpose: Triple-negative breast cancers account for 15% of breast carcinomas and, when present as early-stage disease, they are associated with higher rates of recurrence and early distant metastasis risk when compared to hormone receptor positive and human epidermal growth factor receptor (HER-2) positive breast cancers. In this study we aimed to explore the basic clinicopathological characteristics, prognostic factors and recurrence patterns of non-metastatic triple negative breast cancer patients. Methods: In this study 561 non-metastatic triple-negative breast cancer female patients admitted to 8 different cancer centers in Turkey between 2000 and 2010 were retrospectively evaluated through their medical records, to identify the basic clinico-pathological characteristics, prognostic factors and recurrence patterns. Results: The ratio of triple-negative breast cancer was 12%. The median age of patients was 48 years, of whom 311 (55.4%) were premenopausal. The majority had early-stage breast cancer at the time of diagnosis (16.8% stage I, 48.1% stage II, 35.1 % stage III) and the most commonly identified variant was invasive ductal carcinoma (84.1%). Grade II and III tumors were 27.1 and 48.5%, respectively. Adjuvant chemotherapy was administered to 90.5% of women and adjuvant radiotherapy to 41.2%. Median patient follow up was 28 months (range 3-290). During the follow up period 134 (23.8%) patients developed metastatic disease. In most of these cases, metastatic sites were bone, soft tissue, and lung. Factors affecting disease free survival (DFS) and overall survival (OS) were age (both p

Purpose: Triple-negative breast cancers account for 15% of breast carcinomas and, when present as early-stage disease, they are associated with higher rates of recurrence and early distant metastasis risk when compared to hormone receptor positive and human epidermal growth factor receptor (HER-2) positive breast cancers. In this study we aimed to explore the basic clinicopathological characteristics, prognostic factors and recurrence patterns of non-metastatic triple negative breast cancer patients. Methods: In this study 561 non-metastatic triple-negative breast cancer female patients admitted to 8 different cancer centers in Turkey between 2000 and 2010 were retrospectively evaluated through their medical records, to identify the basic clinico-pathological characteristics, prognostic factors and recurrence patterns. Results: The ratio of triple-negative breast cancer was 12%. The median age of patients was 48 years, of whom 311 (55.4%) were premenopausal. The majority had early-stage breast cancer at the time of diagnosis (16.8% stage I, 48.1% stage II, 35.1 % stage III) and the most commonly identified variant was invasive ductal carcinoma (84.1%). Grade II and III tumors were 27.1 and 48.5%, respectively. Adjuvant chemotherapy was administered to 90.5% of women and adjuvant radiotherapy to 41.2%. Median patient follow up was 28 months (range 3-290). During the follow up period 134 (23.8%) patients developed metastatic disease. In most of these cases, metastatic sites were bone, soft tissue, and lung. Factors affecting disease free survival (DFS) and overall survival (OS) were age (both p

The majority of patients with pancreatic cancer is of advanced disease. Several randomized Phase II and III trials suggest that the combination of gemcitabine and cisplatin (GemCis) response rates were higher than Gemcitabine (Gem) alone, however the trials were not enough powered to indicate a statistically significant prolongation of survival in patients with advanced pancreatic adenocarcinoma. The aim of this retrospective multicenter study is to evaluated the efficiency of Gem alone versus GemCis in patients with locally advanced and/or metastatic pancreatic adenocarcinoma .A total of 406 patients, from fourteen centers were evaluated retrospectively. All patients received Gem or GemCis as first-line treatment between September 2005 to March 2011. Primary end of this study were to evaluate the toxicity, clinical response rate, progression-free survival (PFS) and overall survival (OS) between the arms. There were 156 patients (M: 98, F: 58) in Gem arm and 250 patients (M: 175, F: 75) in the combination arm. Gemcitabin arm patients older than the combination arm ( median 63 vs 57.5, p=0.001). In patients with the combination arm had a higher dose reduction (25.2% vs 11.3%, p=0.001) and dose delay (34% vs 16.8%, p=0.001). Among patients with the combination and Gemcitabin arm gender, diabetes mellitus, performance status, cholestasis, grade, stage did not have a statistically difference (p0.05). Clinical response rate to the combination arm was higher than the Gem arm (69.0% vs 49.7%, p=0.001). PFS was more favorable in the GemCis arm than Gem alone, but the difference did not attain statistical significance (8.9 vs 6.0, p=0.08). OS was not significantly superior in the GemCis arm (12.0 vs 10.2, p0.05). Grade III-IV hematologic and nonhematologic toxicity were higher in the combination arm. PFS was more favorable in the GemCis arm than Gem alone, but the difference did not attain statistical significance. OS was not significantly superior in the GemCis arm.

Purpose: The majority of patients with pancreatic cancer present with advanced disease. Systemic chemotherapy for patients with pancreatic cancer has limited impact on overall survival (OS). Patients eligible for chemotherapy should be selected carefully. The aim of this study was to analyse prognostic factors for OS in advanced pancreatic cancer patients treated with first-line palliative chemotherapy with gemcitabine alone or gemcitabine plus cisplatin.

The radiative strength functions of 96Mo have been reanalyzed. The enhanced gamma strength for E_gamma < 3 - 4 MeV is confirmed., 2 figures

Nuclear level densities for $^{56,57}$Fe have been extracted from the primary $\gamma$-ray spectra using ($^3$He,$^3$He$^{\prime}\gamma$) and ($^3$He,$\alpha \gamma$) reactions. Nuclear thermodynamic properties for $^{56}$Fe and $^{57}$Fe are investigated using the experimental level densities. These properties include entropy, Helmholtz free energy, caloric curves, chemical potential, and heat capacity. In particular, the breaking of Cooper pairs and single-quasiparticle entropy are discussed and shown to be important concepts for describing nuclear level density. Microscopic model calculations are performed for level densities of $^{56,57}$Fe. The experimental and calculated level densities are compared. The average number of broken Cooper pairs and the parity distribution are extracted as a function of excitation energy for $^{56,57}$Fe from the model calculations., Comment: 24 pages, 11 figures

Excited states in Cr46 were sought using the C12(Ar36,2n) reaction. Gamma rays were detected with the Gammasphere array, and the Z value of the reaction products was determined with an ionization chamber located at the focal plane of the Fragment Mass Analyzer. In addition to the ground-state band observed up to IÏ€=10+ (tentatively 12+), five states are proposed to belong to the 3- band. The mirror energy differences with the analog states in Ti46 present a pronounced staggering effect between the odd and even spin members that is reproduced well by shell-model calculations incorporating the different Coulomb contributions, monopole, multipole, and single-particle effects together with an isospin-nonconserving interaction that accounts for the so-called J=2 anomaly. Dramatically different E1 decay patterns for members of the 3- band between the Cr46 and Ti46 mirrors are also observed.

Nuclear level densities and radiative strength functions (RSFs) are measured for ⁵⁶˙⁵⁷Fe and ⁹⁶˙⁹⁷Mo isotopes using a light ion reaction. Observed step structure in the level density curves is explained tentatively by a schematic microscopic model implemented with seniority-conserving and seniority-nonconserving interactions. An unusual strong enhancement of the soft (EY ≤ 2 MeV) radiative strength function for transitions in the quasicontinuum is observed in these isotopes. Experimental two-step cascade intensities with soft primary transitions from the ⁵⁶Fe(n,2y)⁵⁷Fe reaction confirm the enhancement., ⁵⁶˙⁵⁷Fe ve ⁹⁶˙⁹⁷Mo izotoplarının nükleer durum yoğunluğu ve gama kuvvet fonksiyonu hafif-iyon reaksiyonu kullanılarak ölçülmüştür. Durum yoğunluğu eğrilerinde gözlenen merdiven yapısı, sinyorite-korunumlu ve sinyorite-korunumsuz etkileşmeleri içeren bir şematik mikroskopik model ile açıklanmıştır. Bu izotoplarda yirast eğrisinin birçok MeV üzerinden gelen gama geçişlerinde, gama kuvvet fonksiyonlarının düşük enerjili gamalar için çok yüksek olduğu gözlenmiştir. ⁵⁶Fe(n,2y) ⁵⁷Fe reaksiyonunu kullanan iki-adım gama geçişi deneyi, düşük enerjili gama ışınlarının daha büyük şiddetle yayınlandığını doğrulamaktadır.

The $^{55}$Mn$(d,n)^{56}$Fe differential cross section is measured at $E_d=7$ MeV\@. The $^{56}$Fe level density obtained from neutron evaporation spectra is compared to the level density extracted from the $^{57}$Fe$(^3$He,$\alpha\gamma)^{56}$Fe reaction by the Oslo-type technique. Good agreement is found between the level densities determined by the two methods. With the level density function obtained from the neutron evaporation spectra, the $^{56}$Fe $\gamma$-strength function is also determined from the first-generation $\gamma$ matrix of the Oslo experiment. The good agreement between the past and present results for the $\gamma$-strength function supports the validity of both methods and is consistent with the low-energy enhancement of the $\gamma$ strength below $\sim 4$ MeV first discovered by the Oslo method in iron and molybdenum isotopes., Comment: 7 pages, 5 figures

The two published literature values [Greenwood et al., Nucl. Phys. A252, 260 (1975) and Gelletly et al., J. Phys. G 11, 1055 (1985)] for absolute primary gamma intensities following thermal neutron capture of 171Yb differ in average by a factor of three. We have resolved this conflict in favor of Greenwood et al. by a measurement of primary versus secondary intensities., Comment: two pages including one figure

The $^{55}$Mn$(d,n)^{56}$Fe differential cross section is measured at $E_d=7$ MeV\@. The $^{56}$Fe level density obtained from neutron evaporation spectra is compared to the level density extracted from the $^{57}$Fe$(^3$He,$����)^{56}$Fe reaction by the Oslo-type technique. Good agreement is found between the level densities determined by the two methods. With the level density function obtained from the neutron evaporation spectra, the $^{56}$Fe $��$-strength function is also determined from the first-generation $��$ matrix of the Oslo experiment. The good agreement between the past and present results for the $��$-strength function supports the validity of both methods and is consistent with the low-energy enhancement of the $��$ strength below $\sim 4$ MeV first discovered by the Oslo method in iron and molybdenum isotopes., 7 pages, 5 figures

Level densities for 93-98Mo have been extracted using the (3He,alpha gamma) and (3He,3He' gamma) reactions. From the level densities thermodynamical quantities such as temperature and heat capacity can be deduced. Data have been analyzed by utilizing both the microcanonical and the canonical ensemble. Structures in the microcanonical temperature are consistent with the breaking of nucleon Cooper pairs. The S-shape of the heat capacity curves found within the canonical ensemble is interpreted as consistent with a pairing phase transition with a critical temperature for the quenching of pairing correlations at T_c ~ 0.7-1.0 MeV., 21 pages, including 12 figures

Radiative strength functions (RSFs) in 93-98Mo have been extracted using the (3He,alpha gamma) and (3He,3He' gamma) reactions. The RSFs are U-shaped as function of gamma energy with a minimum at around E_gamma=3 MeV. The minimum values increase with neutron number due to the increase in the low-energy tail of the giant electric dipole resonance with nuclear deformation. The unexpected strong increase in strength below E_gamma=3 MeV, here called soft pole, is established for all 93-98Mo isotopes. The soft pole is present at all initial excitation energies in the 5-8 MeV region., 10 pages, including 4 figures

Two-step-cascade spectra in 172-Yb have been measured after thermal neutron capture. They are compared to calculations based on experimental values of the level density and radiative strength function (RSF) obtained from the 173-Yb(3-He,alpha gamma)172-Yb reaction. The multipolarity of a 6.5(15) mu_N^2 resonance at E_gamma=3.3(1) MeV in the RSF is determined to be M1 by this comparison., 4 pages including 3 figures

Purpose: The purpose of this study was to evaluate the clinico pathological features of patients with grade III glial tumors associated with recurrence after treatment.

42nd European-Society-for-Medical-Oncology Congress (ESMO) -- SEP 08-12, 2017 -- Madrid, SPAIN, WOS: 000411324001166, …, European Soc Med Oncol

The majority of patients with pancreatic cancer is of advanced disease. Several randomized Phase II and III trials suggest that the combination of gemcitabine and cisplatin (GemCis) response rates were higher than Gemcitabine (Gem) alone, however the trials were not enough powered to indicate a statistically significant prolongation of survival in patients with advanced pancreatic adenocarcinoma. The aim of this retrospective multicenter study is to evaluated the efficiency of Gem alone versus GemCis in patients with locally advanced and/or metastatic pancreatic adenocarcinoma. A total of 406 patients, from fourteen centers were evaluated retrospectively. All patients received Gem or GemCis as first-line treatment between September 2005 to March 2011. Primary end of this study were to evaluate the toxicity, clinical response rate, progression-free survival (PFS) and overall survival (OS) between the arms. There were 156 patients (M: 98, F: 58) in Gem arm and 250 patients (M: 175, F: 75) in the combination arm. Gemcitabin arm patients older than the combination arm ( median 63 vs 57.5, p=0.001). In patients with the combination arm had a higher dose reduction (25.2% vs 11.3%, p=0.001) and dose delay (34% vs 16.8%, p=0.001). Among patients with the combination and Gemcitabin arm gender, diabetes mellitus, performance status, cholestasis, grade, stage did not have a statistically difference (p>0.05). Clinical response rate to the combination arm was higher than the Gem arm (69.0% vs 49.7%, p=0.001). PFS was more favorable in the GemCis arm than Gem alone, but the difference did not attain statistical significance (8.9 vs 6.0, p=0.08). OS was not significantly superior in the GemCis arm (12.0 vs 10.2, p>0.05). Grade III-IV hematologic and nonhematologic toxicity were higher in the combination arm. PFS was more favorable in the GemCis arm than Gem alone, but the difference did not attain statistical significance. OS was not significantly superior in the GemCis arm.