New Molecular Collisional Interaction Effect in Low-Energy Sputtering

Y. Yao, Z. Hargitai, M. Albert, R. G. Albridge, A. V. Barnes, J. M. Gilligan, B. Pratt Ferguson, G. Lüpke, V. D. Gordon (currently with UT Austin), and N. H. Tolk are with the Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 -- J. C. Tully is with the Department of Physics and Department of Chemistry, Yale University, New Haven, Connecticut 06520 -- G. Betz and W. Husinsky are with the Institut für Allgemeine Physik, Technische Universität Wien, A-1040 Vienna, AustriaAn unexpected pronounced enhancement is observed in sputtering yields per atom for N2+ compared to N+ from a polycrystalline gold target. This effect is seen when the kinetic energy per projectile atom is below 500 eV and increases as projectile energy decreases to near-threshold energies. Enhancements for O2+ over O+ begin at even lower kinetic energies below 100 eV per atom. This new molecular interaction effect may be explained qualitatively by invoking a simple energy transfer model which involves the vibrational frequency of the molecule and the collisional interaction time. [S0031-9007(98)06668-X]Chemistr

Effect of the COVID-19 pandemic on surgery for indeterminate thyroid nodules (THYCOVID): a retrospective, international, multicentre, cross-sectional study

Background Since its outbreak in early 2020, the COVID-19 pandemic has diverted resources from non-urgent and elective procedures, leading to diagnosis and treatment delays, with an increased number of neoplasms at advanced stages worldwide. The aims of this study were to quantify the reduction in surgical activity for indeterminate thyroid nodules during the COVID-19 pandemic; and to evaluate whether delays in surgery led to an increased occurrence of aggressive tumours.Methods In this retrospective, international, cross-sectional study, centres were invited to participate in June 22, 2022; each centre joining the study was asked to provide data from medical records on all surgical thyroidectomies consecutively performed from Jan 1, 2019, to Dec 31, 2021. Patients with indeterminate thyroid nodules were divided into three groups according to when they underwent surgery: from Jan 1, 2019, to Feb 29, 2020 (global prepandemic phase), from March 1, 2020, to May 31, 2021 (pandemic escalation phase), and from June 1 to Dec 31, 2021 (pandemic decrease phase). The main outcomes were, for each phase, the number of surgeries for indeterminate thyroid nodules, and in patients with a postoperative diagnosis of thyroid cancers, the occurrence of tumours larger than 10 mm, extrathyroidal extension, lymph node metastases, vascular invasion, distant metastases, and tumours at high risk of structural disease recurrence. Univariate analysis was used to compare the probability of aggressive thyroid features between the first and third study phases. The study was registered on ClinicalTrials.gov, NCT05178186.Findings Data from 157 centres (n=49 countries) on 87 467 patients who underwent surgery for benign and malignant thyroid disease were collected, of whom 22 974 patients (18 052 [78 center dot 6%] female patients and 4922 [21 center dot 4%] male patients) received surgery for indeterminate thyroid nodules. We observed a significant reduction in surgery for indeterminate thyroid nodules during the pandemic escalation phase (median monthly surgeries per centre, 1 center dot 4 [IQR 0 center dot 6-3 center dot 4]) compared with the prepandemic phase (2 center dot 0 [0 center dot 9-3 center dot 7]; p<0 center dot 0001) and pandemic decrease phase (2 center dot 3 [1 center dot 0-5 center dot 0]; p<0 center dot 0001). Compared with the prepandemic phase, in the pandemic decrease phase we observed an increased occurrence of thyroid tumours larger than 10 mm (2554 [69 center dot 0%] of 3704 vs 1515 [71 center dot 5%] of 2119; OR 1 center dot 1 [95% CI 1 center dot 0-1 center dot 3]; p=0 center dot 042), lymph node metastases (343 [9 center dot 3%] vs 264 [12 center dot 5%]; OR 1 center dot 4 [1 center dot 2-1 center dot 7]; p=0 center dot 0001), and tumours at high risk of structural disease recurrence (203 [5 center dot 7%] of 3584 vs 155 [7 center dot 7%] of 2006; OR 1 center dot 4 [1 center dot 1-1 center dot 7]; p=0 center dot 0039).Interpretation Our study suggests that the reduction in surgical activity for indeterminate thyroid nodules during the COVID-19 pandemic period could have led to an increased occurrence of aggressive thyroid tumours. However, other compelling hypotheses, including increased selection of patients with aggressive malignancies during this period, should be considered. We suggest that surgery for indeterminate thyroid nodules should no longer be postponed even in future instances of pandemic escalation.Funding None.Copyright (c) 2023 Published by Elsevier Ltd. All rights reserved

Plasma Neurofilament Heavy Chain Levels Correlate to Markers of Late Stage Disease Progression and Treatment Response in SOD1(G93A) Mice that Model ALS

Background: Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disorder characterised by progressive degeneration of motor neurons leading to death, typically within 3–5 years of symptom onset. The diagnosis of ALS is largely reliant on clinical assessment and electrophysiological findings. Neither specific investigative tools nor reliable biomarkers are currently available to enable an early diagnosis or monitoring of disease progression, hindering the design of treatment trials. Methodology/Principal Findings: In this study, using the well-established SOD1G93A mouse model of ALS and a new in-house ELISA method, we have validated that plasma neurofilament heavy chain protein (NfH) levels correlate with both functional markers of late stage disease progression and treatment response. We detected a significant increase in plasma levels of phosphorylated NfH during disease progression in SOD1G93A mice from 105 days onwards. Moreover, increased plasma NfH levels correlated with the decline in muscle force, motor unit survival and, more significantly, with the loss of spinal motor neurons in SOD1 mice during this critical period of decline. Importantly, mice treated with the disease modifying compound arimoclomol had lower plasma NfH levels, suggesting plasma NfH levels could be validated as an outcome measure for treatment trials. Conclusions/Significance: These results show that plasma NfH levels closely reflect later stages of disease progression and therapeutic response in the SOD1G93A mouse model of ALS and may potentially be a valuable biomarker of later disease progression in ALS

Lifetime offspring production in relation to breeding lifespan, attractiveness, and mating status in male collared flycatchers

As a comprehensive fitness parameter, lifetime reproductive success (LRS) is influenced by many different environmental and genetic factors, among which longevity is one of the most important. These factors can be reflected in secondary sexual characters, which may affect the life histories of individuals via social relations with conspecifics. Facultative polygyny in birds is another conspicuous reproductive trait that potentially increases male reproductive success, but lifetime success data in relation to polygyny are scarce. Here, we used 17 years of breeding data to quantify the LRS of male collared flycatchers (Ficedula albicollis) on the basis of lifetime recruitment of offspring. Breeding lifespan showed a positive relationship with LRS, and it was also significantly associated with mean recruitment of offspring per breeding year. Body size and sexually selected forehead patch size did not predict the number of recruits. Polygyny was positively associated with LRS, but when we corrected for lifespan, this relationship disappeared. Our results demonstrate that the relationship between longevity and LRS is not explained by the higher number of reproductive attempts when living longer, and question the adaptive value of polygyny in this population. The lack of association between forehead patch size and recruitment suggests that forehead patch is a poor indicator of phenotypic quality in our birds. © 2012 Springer-Verlag.Peer Reviewe

Stress related changes of cell surface hydrophilicity in Bacillus subtilis

The changes of cell surface hydrophilicity in Bacillus subtilis were analyzed in response to oxygen-limitation, heat shock, salt stress, pH-shock, phosphate- and carbon-limitation.  Although cell surface hydrophilicity varied during growth phases, an increase of surface hydrophilicity was observed under several of these stress conditions.  An observed drop in intracellular GTP and/or ATP may be an element of the signal transduction pathway leading to an increase in surface hydrophilicity in response to environmental stresses.  Attachment of cells to soil particles under salt stress conditions is strongly influenced by the degS/degU two-component system, which thereby provides a mechanism for the bacteria to escape from the hostile environment

Measurement of internal magnetic domain structures by using backscattered electrons in a SEM

This paper introduces a method enabling the investigation of the magnetic domain structure in the bulk of a ferromagnet utilizing the backscattered electrons of a scanning electron microscope as small electron probes to sense the internal magnetic fields. By changing the primary energy of the electron beam, different electron penetration depths can be generated. The resulting domain pictures correspond to the average magnetic field at the given electron penetration depth. By taking pictures at two different primary electron energies and subtracting them from each other, the subtracted picture contains information about the average magnetic fields in the layer between the two penetration depths