scholarly journals 1. The Origin of Iron Meteorites

1977 ◽  
Vol 39 ◽  
pp. 405-413
Author(s):  
W. R. Kelly ◽  
E. R. Rambaldi ◽  
J. W. Larimer
Keyword(s):  
Melting Process ◽  
Iron Meteorites ◽  
Forming Process ◽  
Silicate Inclusions ◽  
Partial Melting Process ◽  
Group Iva ◽  
History Of ◽  
Advanced Stages ◽  
Flow Group ◽  
Cosmic History

The chemistry of iron meteorites is compared to predictions of the chemical fractionations that develop during the cosmic history of the metal phase, from condensation and accretion through melting, segregation and freezing. Of the 12 resolved iron meteorite groups, 3 appear to have evolved in bodies which accreted at T > 1000° K. In several cases, the core-forming process seems to have ceased prematurely, just as the metal began to melt and flow (group IAB with its silicate inclusions) or after the metal aggregated into pods but before it sank to form a core (group IVA, with groups IIAB and IIIAB being in more advanced stages). The Shaw chondrite contains residual metal from a partial melting process, as required to complement the fractional melts which refroze prematurely in the case of group IAB meteorites.

scholarly journals Galaxy and mass assembly (GAMA): the inferred mass–metallicity relation from z = 0 to 3.5 via forensic SED fitting

2021 ◽  
Vol 503 (3) ◽  
pp. 3309-3325
Author(s):  
Sabine Bellstedt ◽  
Aaron S G Robotham ◽  
Simon P Driver ◽  
Jessica E Thorne ◽  
Luke J M Davies ◽  
...  
Keyword(s):  
Star Formation ◽  
Gas Phase ◽  
Large Range ◽  
Three Dimensional ◽  
Cosmic Time ◽  
Slowing Down ◽  
History Of ◽  
Mass Assembly ◽  
Star Formation Histories ◽  
Cosmic History

ABSTRACT We analyse the metallicity histories of ∼4500 galaxies from the GAMA survey at z < 0.06 modelled by the SED-fitting code ProSpect using an evolving metallicity implementation. These metallicity histories, in combination with the associated star formation histories, allow us to analyse the inferred gas-phase mass–metallicity relation. Furthermore, we extract the mass–metallicity relation at a sequence of epochs in cosmic history, to track the evolving mass–metallicity relation with time. Through comparison with observations of gas-phase metallicity over a large range of redshifts, we show that, remarkably, our forensic SED analysis has produced an evolving mass–metallicity relationship that is consistent with observations at all epochs. We additionally analyse the three-dimensional mass–metallicity–SFR space, showing that galaxies occupy a clearly defined plane. This plane is shown to be subtly evolving, displaying an increased tilt with time caused by general enrichment, and also the slowing down of star formation with cosmic time. This evolution is most apparent at lookback times greater than 7 Gyr. The trends in metallicity recovered in this work highlight that the evolving metallicity implementation used within the SED-fitting code ProSpect produces reasonable metallicity results over the history of a galaxy. This is expected to provide a significant improvement to the accuracy of the SED-fitting outputs.

scholarly journals Long-Term Follow-Up of a Female Patient Treated with Olaparib—Hope for a Long Life without Relapse?

2021 ◽  
Vol 18 (7) ◽  
pp. 3430
Author(s):  
Mateusz Kozłowski ◽  
Katarzyna Nowak ◽  
Aneta Cymbaluk-Płoska
Keyword(s):  
Ovarian Cancer ◽  
Parp Inhibitor ◽  
Brca1 Gene ◽  
High Specificity ◽  
Reproductive Organs ◽  
Platinum Based Chemotherapy ◽  
Long Term Follow Up ◽  
History Of ◽  
Advanced Stages

Ovarian cancer is one of the most common cancers of the reproductive organs. As there are no symptoms in the early stages, it is mainly detected in the advanced stages. Even then, the symptoms are non-specific and include, for example, abdominal pain, early satiety, or changes in bowel habits. Both biochemical marker levels and imaging studies are used in the initial diagnosis. However, it should be emphasized that they are not characterized by high specificity. Treatment is multistage, and usually first-line debulking surgery is used followed by platinum-based chemotherapy. Here we present a clinical case of a 56-year-old female, a carrier of a mutation in the BRCA1 gene, with a history of breast cancer and with recurrent epithelial ovarian cancer. The patient was qualified for treatment with a PARP inhibitor and is currently undergoing treatment with olaparib. In the patient’s follow up of 50 months to date, there has been no recurrence of cancer. Few side effects have been observed, and the most serious one that can be effectively treated is anemia. On the basis of the described case, the authors concluded that olaparib treatment is effective, relatively safe, and does not significantly affect daily functioning.

scholarly journals A history of uremic toxicity and of the European Uremic Toxin Work Group (EUTox)

2021 ◽  
Author(s):  
Raymond Vanholder ◽  
Angel Argiles ◽  
Joachim Jankowski ◽  
Keyword(s):  
Work Group ◽  
Target Identification ◽  
Kidney Injury ◽  
Uremic Toxins ◽  
Uremic Toxin ◽  
Post Translational Modifications ◽  
History Of ◽  
Advanced Stages ◽  
Uremic Syndrome

Abstract The uremic syndrome is a complex clinical picture developing in the advanced stages of chronic kidney disease (CKD) resulting in a myriad of complications and a high early mortality. This picture is to a significant extent defined by retention of metabolites and peptides that with a preserved kidney function are excreted or degraded by the kidneys. In as far as those solutes have a negative biological/biochemical impact, they are called uremic toxins. Here, we describe the historical evolution of the scientific knowledge about uremic toxins and the role played in this process by the European Uremic Toxin Work Group (EUTox) during the last two decades. The earliest knowledge about a uremic toxin goes back to the early 17th century when the existence of what later would appear to be urea was recognized. It cost about two further centuries to better define the role of urea and its link to kidney failure and one more century to identify the relevance of post-translational modifications caused by urea such as carbamoylation. The knowledge progressively extended, especially from 1980 on, by the identification of more and more toxins and their adverse biological/biochemical impact. Progress of knowledge was paralleled and impacted by evolution of dialysis strategies. The last two decades, when Insights grew exponentially, coincides with the foundation and activity of EUTox. In the final section we summarize the role and accomplishments of EUTox and the part it is likely to play in future action, which should be organized around focus points like biomarker and potential target identification, intestinal generation, toxicity mechanisms and their correction, kidney and extracorporeal removal, patient-oriented outcomes, and toxin characteristics in acute kidney injury and transplantation.

scholarly journals Intensive Improvement of Cementite Synthesis

2020 ◽  
Vol 5 (2) ◽  
pp. 218-220
Author(s):  
Amir Peyman Soleymani ◽  
Masoud Panjepour ◽  
Mahmood Meratian
Keyword(s):  
Mechanical Properties ◽  
Mechanical Activation ◽  
Carbon Content ◽  
Partial Melting ◽  
Melting Process ◽  
Free Carbon ◽  
Partial Melting Process

Cementite extraordinary mechanical properties have drawn the attention of researchers in recent years. But, the limited methods for the production of this material, led to the production of iron with more than 2.1%wt carbon content beside free carbon by simultaneous thermal-mechanical activation of hematite and graphite mixture at 800°C for 6 hours in the present research. Then, a structure with more than 80%wt cementite was obtained through partial melting process at 1180°C for 25 minutes.

scholarly journals Have we seen all the galaxies that comprise the cosmic infrared background at 250 μm ≤λ ≤ 500 μm?

2019 ◽  
Author(s):  
S Duivenvoorden ◽  
S Oliver ◽  
M Béthermin ◽  
D L Clements ◽  
G De Zotti ◽  
...  
Keyword(s):  
Large Range ◽  
Star Formation History ◽  
Large Area ◽  
Substantial Fraction ◽  
Formation History ◽  
Infrared Background ◽  
History Of ◽  
Cosmic Infrared Background ◽  
Number Counts ◽  
Cosmic History

Abstract The cosmic infrared background (CIB) provides a fundamental observational constraint on the star-formation history of galaxies over cosmic history. We estimate the contribution to the CIB from catalogued galaxies in the COSMOS field by using a novel map fitting technique on the Herschel SPIRE maps. Prior galaxy positions are obtained using detections over a large range in wavelengths in the Ks–3 GHz range. Our method simultaneously fits the galaxies, the system foreground, and the leakage of flux from galaxies located in masked areas and corrects for an “over-fitting” effect not previously accounted for in stacking methods. We explore the contribution to the CIB as a function of galaxy survey wavelength and depth. We find high contributions to the CIB with the deep r (mAB ≤ 26.5), Ks (mAB ≤ 24.0) and 3.6 μm (mAB ≤ 25.5) catalogues. We combine these three deep catalogues and find a total CIB contributions of 10.5 ± 1.6, 6.7 ± 1.5 and 3.1 ± 0.7 nWm−2sr−1 at 250, 350 and 500 μm, respectively. Our CIB estimates are consistent with recent phenomenological models, prior based SPIRE number counts and with (though more precise than) the diffuse total measured by FIRAS. Our results raise the interesting prospect that the CIB contribution at λ ≤ 500 μm from known galaxies has converged. Future large-area surveys like those with the Large Synoptic Survey Telescope are therefore likely to resolve a substantial fraction of the population responsible for the CIB at 250 μm ≤λ ≤ 500 μm.

Thermal and impact histories of reheated group IVA, IVB, and ungrouped iron meteorites and their parent asteroids

2011 ◽  
Vol 46 (9) ◽  
pp. 1227-1252 ◽  
Author(s):  
J. YANG ◽  
J. I. GOLDSTEIN ◽  
E. R. D. SCOTT ◽  
J. R. MICHAEL ◽  
P. G. KOTULA ◽  
...  
Keyword(s):  
Iron Meteorites ◽  
Group Iva

scholarly journals Lymphoepithelioma-Like Cholangiocarcinoma Associated With HCV: A Case Report and a Review of the Literature

2017 ◽  
Vol 102 (1-2) ◽  
pp. 64-69
Author(s):  
Hiroya Akabori ◽  
Mitsuaki Ishida ◽  
Hisanori Shiomi ◽  
Hiromitsu Maehira ◽  
Koichiro Murakami ◽  
...  
Keyword(s):  
Colon Cancer ◽  
Therapeutic Option ◽  
Undifferentiated Carcinoma ◽  
Good Prognosis ◽  
Advanced Colon Cancer ◽  
Lymphoid Stroma ◽  
Resected Tumor ◽  
Histologic Pattern ◽  
History Of ◽  
Advanced Stages

Lymphoepithelioma-like carcinoma is a particular form of undifferentiated carcinoma characterized by a prominent lymphoid stroma that was originally described in the nasopharynx. We present a case of hepatitis C virus (HCV)–associated lymphoepithelioma-like cholangiocarcinoma (LEL-CC), located at the liver, in a patient with history of malignancy. A 79-year-old man underwent partial hepatectomy with lymphadenectomy for a suspected metastasis of colon cancer 2.5 years after hemicolectomy for advanced colon cancer followed by adjuvant chemotherapy. The resected tumor was diagnosed as LEL-CC via a distinct histologic pattern with dense lymphoplasma cell infiltration. According to the available literature, our report describes a rare cases of HCV-associated LEL-CC that coexisted with other malignancy and that was associated with survival for more than 3 years after surgery, suggesting that surgical resection may be the recommended therapeutic option for LEL-CC to provide a definitive diagnosis as well as obtain a good prognosis, even in advanced stages of LEL-CC.

Innovations in retinoblastoma treatment and reflection to enucleation rate of 362 eyes of 262 CASES: Twenty years retrospective assessment at Ankara University.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e22509-e22509
Author(s):  
Emel Cabi Unal ◽  
Hande Tosun ◽  
Nurdan Tacyildiz ◽  
Handan Dincaslan ◽  
Kaan Gunduz ◽  
...  
Keyword(s):  
Local Treatment ◽  
Vitreous Hemorrhage ◽  
Systemic Involvement ◽  
Retrospective Assessment ◽  
Recent Developments ◽  
History Of ◽  
Group A ◽  
Advanced Stages ◽  
Group B ◽  
Group D

e22509 Background: Enucleation used as the first-line tx option for RB, dx in advanced stages. Methods: To evaluate the enucleation rates of RB cases in 20 years period, to emphasize the recent developments in the tx of RB that contribute to the improvement of tx outcomes. Results: 262 patients, with the dx of RB between June 1998 &December 2018 in Ankara University Departmant of Pediatric Oncology were evaluated retrospectively. The M / F ratio was 1.2, mean age at dx 19.39 mos; 22.7 mos for unilateral &14.1 mos for bilateral dx. 61.8% of the patients had unilateral, 38.2% bilateral RB. 362 eyes were evaluated, 12.5% of the patients had a family history of RB bilateral dx was more frequent. The initial findings were leucocori in 58%& strabismus in 27.9%, similar to the literature. According to ICRB, 6% of the patients were diagnosed in Group A, 22% in Group B, 19% in Group C, 22% in Group D and 31% in Group E. Patients with bilateral dx were diagnosed at an earlier stage. Enucleation, in 50.5% of 362 eyes analyzed. There was no enucleated eye in Group A. In group B,10.1% of the eyes were enucleated, as of recurrence. 32.3% of eyes in Group C, 60.7% of eyes in Group D and 92.9% of eyes in Group E were enucleated. Enucleation was performed in 25.4% of the eyes within the first month after dx as of the advanced stage. 33.7% of of the eyes who did not have enucleation at the time of dx required enucleation at FU. The most common causes of enucleation were tumor recurrence, total retinal detachment & vitreous hemorrhage. The tx methods other than enucleation are systemic CT, RT & local treatments; cryotherapy, thermotherapy, episcleral brachytherapy, intravitreal CT & intraarterial CT. Systemic CT applied to 77% of the patients.CT protocol were VEC and ICE.RT was applied to 17% of the patients. After 2012, radiotherapy was used only in 2 patients with systemic involvement. Cryotherapy was performed in 48.3% of the eyes, thermotherapy in 38.6%, episcleral brachytherapy in 3.8% of the eyes included.Intraarterial CT to be used after 2004 was applied to 16.6% of eyes dx & intravitreal CT was used after 2009 was applied to13.2% of eyes. Enucleation was avoided in 84.6% of eyes in which these two tx modalities were applied together. Enucleation rates of 56.3% &61.2% between 1998-2004 and 2004-2009, respectively; with active use of intraarterial and intravitreal CT, decreased to 40.2% between 2009-2018. Conclusions: It was observed that enucleation rates &RT gradually decreased with using systemic CT and local treatment methods.

Sign in / Sign up

Export Citation Format

Share Document