34 research outputs found
Influence of green state processing on the properties of diamond/zinc sulphide composites
Diamond-reinforced zinc sulphide composites have increased toughness as compared to that of pure zinc sulphide. While the mechanical properties of the composites are relatively insensitive to green state processing, the optical properties are greatly affected by the processing which governs the quality of diamond dispersion. Improved dispersion and hence good optical transmission have been achieved by shear mixing and by freeze milling.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44712/1/10853_2005_Article_BF01154113.pd
CovidNeuroOnc: A UK multicenter, prospective cohort study of the impact of the COVID-19 pandemic on the neuro-oncology service
BackgroundThe COVID-19 pandemic has profoundly affected cancer services. Our objective was to determine the effect of the COVID-19 pandemic on decision making and the resulting outcomes for patients with newly diagnosed or recurrent intracranial tumors.MethodsWe performed a multicenter prospective study of all adult patients discussed in weekly neuro-oncology and skull base multidisciplinary team meetings who had a newly diagnosed or recurrent intracranial (excluding pituitary) tumor between 01 April and 31 May 2020. All patients had at least 30-day follow-up data. Descriptive statistical reporting was used.ResultsThere were 1357 referrals for newly diagnosed or recurrent intracranial tumors across 15 neuro-oncology centers. Of centers with all intracranial tumors, a change in initial management was reported in 8.6% of cases (n = 104/1210). Decisions to change the management plan reduced over time from a peak of 19% referrals at the start of the study to 0% by the end of the study period. Changes in management were reported in 16% (n = 75/466) of cases previously recommended for surgery and 28% of cases previously recommended for chemotherapy (n = 20/72). The reported SARS-CoV-2 infection rate was similar in surgical and non-surgical patients (2.6% vs. 2.4%, P > .9).ConclusionsDisruption to neuro-oncology services in the UK caused by the COVID-19 pandemic was most marked in the first month, affecting all diagnoses. Patients considered for chemotherapy were most affected. In those recommended surgical treatment this was successfully completed. Longer-term outcome data will evaluate oncological treatments received by these patients and overall survival
Metopic synostosis
Premature closure of the metopic suture results in a growth restriction of the frontal bones, which leads to a skull malformation known as trigonocephaly. Over the course of recent decades, its incidence has been rising, currently making it the second most common type of craniosynostosis. Treatment consists of a cranioplasty, usually preformed before the age of 1 year. Metopic synostosis is linked with an increased level of neurodevelopmental delays. Theories on the etiology of these delays range from a reduced volume of the anterior cranial fossa to intrinsic malformations of the brain. This paper aims to provide an overview of this entity by giving an update on the epidemiology, etiology, evolution of treatment, follow-up, and neurodevelopment of metopic synostosis
Quasi-liquid Layers in Grooves of Grain Boundaries and on Grain Surfaces of Polycrystalline Ice Thin Films
In nature, a large proportion of ice is present in a polycrystalline state. Thus, understanding the formation of quasi-liquid layers (QLLs) on/in polycrystalline ice is indispensable for understanding a wide variety of natural phenomena. In this study, we observed surfaces of polycrystalline ice thin films using our advanced optical microscope. We focused our attention on the macroscopic fluidity of objects observed on polycrystalline ice surfaces as evidence for the presence of QLLs. Systematic observations under various temperatures and water vapor pressures showed that, with increasing temperature, QLLs first appeared preferentially in grooves of grain boundaries and continued to exist at -1.9 +/- 0.4 degrees C, irrespective of the water vapor pressure (even in immediate vicinities of the vapor-ice equilibrium curve). From this result, we concluded that the QLLs were formed by melting of grain boundaries to relax lattice mismatches. With a further increase of temperature, droplet-type QLLs appeared on grain surfaces at -0.7 +/- 0.2 degrees C. However, as time elapsed, the droplet-type QLLs on the grain surfaces spontaneously disappeared within 5 +/- 3 min even though temperature and water vapor pressure were kept constant. Such appearance and subsequent disappearance of the droplet-type QLLs on the grain surfaces were observed even under relatively highly supersaturated and undersaturated conditions