A new crysallographic technique has been developed, which has been applied to the problem of locating the cations in a natural olivine crystal with the composition (Mg(0.90)Fe(0.10)Ni(0.004)Mn(0.002))(2)SiO(4). The method uses the variation of characteristic x-ray emission with the direction of an exciting electron beam in an analytical transmission electron microscope. It may be applied to nanometer-sized areas and to concentrations as low as 0.1 atomic percent, is capable of distinguishing neighbors in the periodic table, and does not require external standards. The iron atoms in this crystal are evenly distributed between the two available crystal sites M1 and M2 (49.6 +/- 1 percent on M1), whereas the trace elements nickel and manganese occupy the M1 and M2 positions, respectively (97 +/- 5 percent nickel on M1 and 1 +/- 5 percent manganese on M1).
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http://dx.doi.org/10.1126/science.218.4567.49 | DOI Listing |
J Occup Environ Hyg
January 2025
Institute of Physical Factors and Occupational Health, Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou, Guangdong Province, China.
The noise exposure levels of workers wearing hearing protective devices (HPDs) depend on ambient noise and the protective effect of hearing protectors. This cross-sectional study aimed to adjust for cumulative noise exposure (CNE) based on the effective protection of hearing protection devices and explore the dose-response relationship between noise-induced hearing loss (NIHL) and adjusted cumulative noise exposure. A questionnaire was used to acquire the basic characteristics and occupational information of noise-exposed workers.
View Article and Find Full Text PDFAnn Plast Surg
January 2025
From the Birmingham Hand Centre, University Hospital Birmingham, Birmingham, AL.
Background: Rates of recurrence, metastases, and mortality for squamous cell carcinoma (SCC) of the upper limb have not been clearly defined.
Objective: We aimed to characterize these tumors and assess the long-term outcomes, comparing with current literature.
Methods And Materials: A retrospective review was performed on 100 consecutive primary cutaneous upper limb SCCs managed surgically by a single hand surgeon between 2012 and 2019.
Purpose: Although publicly available cancer-related information online and offline could help patients make informed decisions, it also poses challenges due to prevalent misinformation. Patients need proper provider guidance to ensure they use valid and relevant information in decisions. We identify effective communication approaches for providers when (1) discussing patient-identified information and (2) disagreeing with it.
View Article and Find Full Text PDFClin Exp Dermatol
January 2025
St John's Institute of Dermatology, Guy's and St Thomas' NHS Foundation Trust, London, UK.
Background: In recessive dystrophic epidermolysis bullosa (RDEB), complications like oesophageal strictures, hand contractures, cardiomyopathy and cutaneous squamous cell carcinoma (SCC) may develop, necessitating procedures such as oesophageal dilatation (OD), gastrostomy tube placement and hand surgery.
Objectives: To determine prevalence and age of onset of milestone events by RDEB subtype, specifically dysphagia, first OD, first gastrostomy tube, first hand surgery, cardiomyopathy, first SCC and death.
Methods: The Prospective Epidermolysis Bullosa Longitudinal Evaluation Study (PEBLES) is a register study of individuals with RDEB which records comprehensive EB- and non-EB-related health information.
Asian Pac J Cancer Prev
January 2025
Department of Anatomic Pathology, Faculty of Medicine, Kasralainy, Cairo University, Cairo, Egypt.
Background: Helicobacter pylori bacteria colonize the gastric mucosa and contribute to the occurrence and development of gastrointestinal diseases. According to the WHO, H. pylori bacteria are considered class I carcinogen.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!