Can quasicrystals survive in planetary collisions?

We investigated the compressional behavior of i-AlCuFe quasicrystal using diamond anvil cell under quasi-hydrostatic conditions by in situ angle-dispersive X-ray powder diffraction measurements (in both compression and decompression) up to 76 GPa at ambient temperature using neon as pressure medium. These data were compared with those collected up to 104 GPa using KCl as pressure medium available in literature. In general, both sets of data indicate that individual d-spacing shows a continuous decrease with pressure with no drastic changes associated to structural phase transformations or amorphization. The d/d0, where d0 is the d-spacing at ambient pressure, showed a general isotropic compression behavior. The zero-pressure bulk modulus and its pressure derivative were calculated fitting the volume data to both the Murnaghan- and Birch-Murnaghan equation of state models. Results from this study extend our knowledge on the stability of icosahedrite at very high pressure and reinforce the evidence that natural quasicrystals formed during a shock event in asteroidal collisions and survived for eons in the history of the Solar System. [Figure not available: see fulltext.

BCR-ABL1 doubling-times and halving-times may predict CML response to tyrosine kinase inhibitors

In Chronic Myeloid Leukemia (CML), successful treatment requires accurate molecular monitoring to evaluate disease response and provide timely interventions for patients failing to achieve the desired outcomes. We wanted to determine whether measuring BCR-ABL1 mRNA doubling-times (DTs) could distinguish inconsequential rises in the oncogene’s expression from resistance to tyrosine kinase inhibitors (TKIs). Thus, we retrospectively examined BCR-ABL1 evolution in 305 chronic-phase CML patients receiving imatinib mesylate (IM) as a first line treatment. Patients were subdivided in two groups: those with a confirmed rise in BCR-ABL1 transcripts without MR3.0 loss and those failing IM. We found that the DTs of the former patients were significantly longer than those of patients developing IM resistance (57.80 vs. 41.45 days, p = 0.0114). Interestingly, the DT values of individuals failing second-generation (2G) TKIs after developing IM resistance were considerably shorter than those observed at the time of IM failure (27.20 vs. 41.45 days; p = 0.0035). We next wanted to establish if decreases in BCR-ABL1 transcripts would identify subjects likely to obtain deep molecular responses. We therefore analyzed the BCR-ABL1 halving-times (HTs) of a different cohort comprising 174 individuals receiving IM in first line and observed that, regardless of the time point selected for our analyses (6, 12, or 18 months), HTs were significantly shorter in subjects achieving superior molecular responses (p = 0.002 at 6 months; p < 0.001 at 12 months; p = 0.0099 at 18 months). Moreover, 50 patients receiving 2G TKIs as first line therapy and obtaining an MR3.0 (after 6 months; p = 0.003) or an MR4.0 (after 12 months; p = 0.019) displayed significantly shorter HTs than individuals lacking these molecular responses. Our findings suggest that BCR-ABL1 DTs and HTs are reliable tools to, respectively, identify subjects in MR3.0 that are failing their assigned TKI or to recognize patients likely to achieve deep molecular responses that should be considered for treatment discontinuation

Clinical implications of discordant early molecular responses in CML patients treated with imatinib

A reduction in BCR-ABL1/ABL1IS transcript levels to <10% after 3 months or <1% after 6 months of tyrosine kinase inhibitor therapy are associated with superior clinical outcomes in chronic myeloid leukemia (CML) patients. In this study, we investigated the reliability of multiple BCR-ABL1 thresholds in predicting treatment outcomes for 184 subjects diagnosed with CML and treated with standard-dose imatinib mesylate (IM). With a median follow-up of 61 months, patients with concordant BCR-ABL1/ABL1IS transcripts below the defined thresholds (10% at 3 months and 1% at 6 months) displayed significantly superior rates of event-free survival (86.1% vs. 26.6%) and deep molecular response (≥ MR4; 71.5% vs. 16.1%) compared to individuals with BCR-ABL1/ABL1IS levels above these defined thresholds. We then analyzed the outcomes of subjects displaying discordant molecular transcripts at 3-and 6-month time points. Among these patients, those with BCR-ABL1/ABL1IS values >10% at 3 months but <1% at 6 months fared significantly better than individuals with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (event-free survival 68.2% vs. 32.7%; p < 0.001). Likewise, subjects with BCR-ABL1/ABL1IS at 3 months >10% but <1% at 6 months showed a higher cumulative incidence of MR4 compared to patients with BCR-ABL1/ABL1IS <10% at 3 months but >1% at 6 months (75% vs. 18.2%; p < 0.001). Finally, lower BCR-ABL1/GUSIS transcripts at diagnosis were associated with BCR-ABL1/ABL1IS values <1% at 6 months (p < 0.001). Our data suggest that when assessing early molecular responses to therapy, the 6-month BCR-ABL1/ABL1IS level displays a superior prognostic value compared to the 3-month measurement in patients with discordant oncogenic transcripts at these two pivotal time points

First measurements of the Fe oxidation state of spinel inclusions in olivine single crystals from Vulture (Italy) with the in situ synchrotron micro-Mössbauer technique

The redox state of the Earth's upper mantle (i.e., oxygen fugacity, fO2) is a key variable that influences numerous processes occurring at depth like the mobility of volatile species, partial melting, and metasomatism. It is linked to the oxidation state of peridotite rocks, which is normally determined through the available oxythermobarometers after measuring the chemical composition of equilibrated rock-forming minerals and the Fe3+ in redox-sensitive minerals like spinel or garnet. To date, accurate measurements of Fe3+ / ∑Fe in peridotites have been limited to those peridotites (e.g., harzburgites and lherzolites) for which an oxythermobarometer exists and where spinel (or garnet) crystals can be easily separated and measured by conventional 57Fe Mössbauer spectroscopy. Wehrlitic rocks have been generally formed by the interaction of a lherzolite with carbonatitic melts and, therefore, have recorded the passage of (metasomatic) fluids at mantle conditions. However, no oxythermobarometer exists to determine their equilibrium fO2. The aim of this study was to retrieve the fO2 of the mantle beneath Mt. Vulture volcano (Italy) through the study of a wehrlitic lapillus emitted during the last eruption (∼ 140 kyr ago) that contain olivines with multiple tiny spinel inclusions with sizes &lt; 40 µm. To our knowledge, the Fe oxidation state of these inclusions has been never determined with the Mössbauer technique due to their small sizes. Here, we present measurements of the Fe3+ / ∑Fe using in situ synchrotron Mössbauer spectroscopy coupled with chemical and spectroscopic analysis of both host olivine and spinel inclusions. The results show Fe3+ / ∑Fe ratios of 0.03–0.05 for olivine and 0.40–0.45 for the included spinels, the latter of which appear higher than those reported in literature for mantle spinel harzburgites and lherzolites. Given the evidence of the mantle origin of the trapped spinels, we propose that the high fO2 (between 0.81 and 1.00 log above the fayalite–magnetite–quartz buffer; FMQ) likely results from the interaction between the pristine spinel lherzolite and a CO2-rich metasomatic agent prior to the spinel entrapment in olivines at mantle depths.</p

Meaning in life assessed with the "Schedule for Meaning in Life Evaluation” (SMiLE): a comparison between a cancer patient and student sample

Background: The aims of the study were (a) to assess individual meaning in life (MiL) in a mixed sample of cancer patients with the Schedule for Meaning in Life Evaluation (SMiLE), (b) to evaluate the acceptability of its French version, and (c) to compare it to a student sample. Materials and methods: Consecutive cancer patients (N = 100) treated as outpatients in the University Hospital Lausanne (N = 80) and in a nearby hospice (N = 20) were evaluated with the SMiLE, a reliable and validated respondent-generated instrument for the assessment of MiL. The respondents list three to seven areas, which provide meaning to their life and rate the level of importance (weighting) and satisfaction of each area. Indices of total weighting (index of weighting (IoW), range 20-100), total satisfaction (index of satisfaction (IoS), range 0-100), and total weighted satisfaction (index of weighted satisfaction (IoWS), range 0-100) are calculated. Results: Patients most often indicated areas related to relationships as providing MiL, while material things were listed less often. Since satisfaction with relevant areas was high, cancer patients reported the same level of weighted satisfaction (IoWS) as a healthy student sample, assessed with the SMiLE in a prior validation study. Patients judged the SMiLE as reflecting well their MiL, not distressing to fill in and were moderately positive with regard to its helpfulness. Conclusions: MiL of cancer patients was surprisingly high, possibly due to the "response shift” of the severely ill. The SMiLE might become a useful tool for research and an opener to communication between patients and clinicians about this highly relevant topic in cancer care. Further studies with larger sample sizes and different designs, complemented by qualitative research, are needed to deepen our understanding of this so characteristically human topic, which is so easy to perceive and so difficult to gras

Severe acquired cytomegalovirus infection in a full-term, formula-fed infant: Case Report

<p>Abstract</p> <p>Background</p> <p>Cases of cytomegalovirus colitis are exceptionally reported in immuno-competent infant. The pathogenesis is uncertain but breast-feeding is considered as a main source of postnatal infection.</p> <p>Case Presentation</p> <p>Here we report a full-term, formula-fed infant who developed a severe cytomegalovirus anaemia and colitis when aged 2 months.</p> <p>Conclusion</p> <p>Even if the molecular identity between the cytomegalovirus-isolate of the infant and the maternal virus could not be demonstrated, we confirmed through laboratory investigation that cytomegalovirus infection was acquired postnatally. However, the source of cytomegalovirus infection remained unclear. Alternative modes of cytomegalovirus transmission are discussed.</p

A case–control study of childhood leukaemia and paternal occupational contact level in rural Sweden

In a national case–control study in Sweden, we investigated whether in rural areas (where susceptible individuals are more prevalent than in urban areas) leukaemia risk was higher among the young children of fathers with many work contacts, as the infective hypothesis has predicted. A total of 1935 cases diagnosed in 1958–1998 together with 7736 age-matched (within 1 year) population controls (of whom 970 and 3880 respectively were aged 0–4) were linked to paternal occupational details as recorded in the census closest to the year of birth. Applying the two classifications of occupational contact level used in a study of rural Scotland, the odds ratios for children aged 0–4 years in the highest contact category (which includes teachers) in the most rural Swedish counties were 3.47 (95% CI 1.54, 7.85) and 1.59 (1.07, 2.38) respectively, relative to the medium and low (reference) category; no such excess was found in urban or intermediate counties. There was also a significant positive trend at ages 0–4 in the rural counties across the three levels of increasing occupational contact (P for trend 0.02 and 0.03, respectively), but again not in the urban or intermediate counties. No such effect or trend was found at ages 5–14 in any of the three county groupings. The findings confirm those of a recent study in rural Scotland, and also suggest that unusual population mixing (as occurred in Scotland as a result of the North Sea oil industry) is not a necessary requirement for the effect, since comparable mixing has not been a feature of rural Sweden

A theoretical and experimental analysis of macrodecoration of defects in monocrystalline silicon

Microdefect distribution in a monocrystalline silicon wafer is identified by saturating the wafer with copper at a high temperature followed by copper precipitate growth through rapid cooling followed by surface polishing and subsequent microdefect-decorating etching. The decorated microdefect field consists of etch pits that are formed by the difference in the etching rates of the precipitate influenced region around microdefects, and the etching rate of the surrounding defect-free silicon. Interplay between liquid-phase mass-transport effects and surface kinetics plays a key role in the microdefect decoration. It is shown that the macrodecoration of microdefects is typically realized in the absence of significant effects of the liquid-phase diffusion. The developed phenomenological model leads to classification of etchants as either polishing or potentially decorating and to identification of conditions necessary for an efficient microdefect decoration. The competing effects of kinetics toward microdefect decoration and liquid-phase transport toward surface polishing are quantified by theoretically derived solutions for the decorating efficiency and the polishing efficiency. Autoerosion of the microdefects by mildly polishing etchants is also quantified. Analytical expressions for the microdefect-decorating and microdefect-polishing conditions are presented. Finally, decorating and polishing etchants are experimentally identified from a group of etchants and the proposed theory is verified by experimental data.peer-reviewe