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We report in this article on the measurement of the optical absorption of moderately doped crystalline silicon samples at 1550 nm, which is a candidate material for the main optics of the low temperature interferometer of the Einstein Telescope (ET). We observe a nearly constant absorption from room temperature down to cryogenic temperatures for two silicon samples presenting an optical absorption of 0.029 cm−1 and 780 ppm cm−1, both crystals doped with boron. This is in contradiction to what was assumed previously—a negligible optical absorption at low temperature due to the carrier freezeout. As the main consequence, if the silicon intrinsic absorption can not be lowered, the cross section of the mirror suspension of the ET must be increased to be able to carry away the excess heat generated by the partially absorbed laser beam during the operation of the interferometer. [ABSTRACT FROM AUTHOR]

Study Objectives: Obstructive sleep apnea (OSA) is an under-recognized condition that results in morbidity and mortality. Postoperative complications, including medical emergency team activation (META), are disproportionally increased among surgical patients at risk for OSA. A systematic approach is needed to improve provider recognition and treatment, but protocols that demonstrate improvement in META are lacking. As part of a multidisciplinary quality improvement project, DOISNORE50 (DIS), a sleep apnea questionnaire and proactive safety measure, was algorithmically applied to all perioperative patients., Methods: Consecutive sleep screening was conducted among perioperative patients. Of the 49,567 surgical navigation center patients, 11,932 had previous diagnosis of OSA. Of the 37,572 (96%) patients screened with DIS, 25,171 (66.9%) were Low Risk (DIS < 4), 9,211 (24.5%) were At Risk (DIS ≥ 4), and 3,190 (8.5%) were High Risk (DIS ≥ 6) for OSA, respectively. High Risk patients received same-day sleep consultation. On the day of surgery, patients with Known OSA, At Risk, and High Risk for OSA received an "OSA Precaution Band." An electronic chart reminder alerted admission providers to order postoperative continuous positive airway pressure (CPAP) machine and sleep consult for patients High Risk for OSA., Results: Implementation of a comprehensive program was associated with increased sleep consultation, sleep testing, and inpatient CPAP use ( P < .001). For every 1,000 surgical patients screened, 30 fewer META, including rapid responses, reintubation, code blues, and code strokes, were observed. However, inpatient sleep consultation and inpatient CPAP use were not independently associated with reduced META. In the subgroup of patients hospitalized longer than 3 days, inpatient CPAP use was independently associated with reduced META., Conclusions: In this single-center, institution-wide, multidisciplinary-approach, quality improvement project, a comprehensive OSA screening process and treatment algorithm with appropriate postoperative inpatient CPAP therapy and inpatient sleep consultations was associated with increased CPAP use and reduced META. Further prospective studies are needed to assess cost, feasibility, and generalizability of these findings., Citation: Namen AM, Forest D, Saha AK, et al. Reduction in medical emergency team activation among postoperative surgical patients at risk for undiagnosed obstructive sleep apnea. J Clin Sleep Med . 2022;18(8):1953-1965., (© 2022 American Academy of Sleep Medicine.)

Study Objectives: Patients with obstructive sleep apnea (OSA) have a disproportionate increase in postoperative complications and medical emergency team activation (META). We previously introduced DOISNORE50 ( D iseases, O bserved apnea, I nsomnia, S noring, N eck circumference > 18 inches, O besity with BMI > 32, R = are you male, E xcessive daytime sleepiness, 50 = age ≥ 50) from sleep questionnaire ISNORED using features associated with increased odds of META in perioperative patients. Performance of DOISNORE50 (DOISNORE) had yet to be tested., Methods: The performance of DOISNORE was tested along with questionnaire ISNORED and STOP-BANG questionnaires among 300 out of 392 participants without known OSA referred to the sleep lab. In study 2, the performance of DOISNORE was tested among 64,949 lives screened in perioperative assessment clinic from 2016 to 2020., Results: Receiver operating characteristic curve demonstrated that best performance was achieved with responses, with area under curve of 0.801. DOISNORE's predictability of OSA risk remained stable from 2018 to 2020 with area under curve of 0.78 and a Cronbach alpha of 0.65. Patients at high risk for OSA (DOISNORE ≥ 6) were associated with an increase of META (odds ratio 1.30, 95% confidence interval 1.12-1.45). Higher relative risk was noted among patients with congestive heart failure and hypercapnia., Conclusions: DOISNORE is predictive of OSA and postoperative META. Perioperative strategies against META should consider DOISNORE questionnaire and focused screening among patients with heart failure and hypercapnia., Citation: Namen AM, Forest D, Saha AK, et al. DOISNORE50: a perioperative sleep questionnaire predictive of obstructive sleep apnea and postoperative medical emergency team activation. A learning health system approach to sleep questionnaire development and screening. J Clin Sleep Med . 2022;18(8):1909-1919., (© 2022 American Academy of Sleep Medicine.)

We report the management of a parturient with undiagnosed hypokalemic periodic paralysis (HOKPP) who underwent epidural analgesia for labor, complicated by an unintentional dural puncture, and the eventual use of epidural anesthesia for cesarean delivery. Following discharge, she represented with lower extremity paresis. After being evaluated for a compressive neuraxial lesion, she made a full recovery following potassium repletion. The obstetric anesthetic implications for patients with HOKPP and how this disorder impacts the evaluation of acute motor weakness in the immediate postpartum period in a patient who recently received a neuraxial procedure are discussed., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 International Anesthesia Research Society.)

The present study compared in vivo protein digestion in a miniature pig model with the dynamic in vitro system DiDGI®, using three digestive compartments (stomach, duodenum, and jejunum + ileum). Two soya-based meals-commercial soya milk and tofu-were studied, each with the same macronutrient content but different macrostructures. Our aim was to first deduce from the in vivo experiments in pigs key digestive parameters such as gastric pH, stomach emptying kinetics, and intestinal transit time, in order to design a relevant set-up for the dynamic in vitro system. Then, we compared digestive samples collected at fixed sampling times from both in vivo and in vitro models regarding different values related to proteolysis. We observed similar evolutions of gastric peptide distribution and duodenal proteolysis between models. Overall, apparent ileal digestibility of nitrogen was similar in vitro and in vivo and the differences between the two meals were conserved between models., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Coating thermal noise is a fundamental limit for precision experiments based on optical and quantum transducers. In this review, after a brief overview of the techniques for coating thermal noise measurements, we present the latest worldwide research activity on low-noise coatings, with a focus on the results obtained at the Laboratoire des Matériaux Avancés. We report new updated values for the T a 2 O 5 , T a 2 O 5 - T i O 2 , and S i O 2 coatings of the Advanced LIGO, Advanced Virgo, and KAGRA detectors, and new results from sputtered N b 2 O 5 , T i O 2 - N b 2 O 5 , T a 2 O 5 - Z r O 2 , M g F 2 , A l F 3 , and silicon nitride coatings. Amorphous silicon, crystalline coatings, high-temperature deposition, multi-material coatings, and composite layers are also briefly discussed, together with the latest developments in structural analyses and models.

This paper describes the making of large mirrors for laser interferometer gravitational wave detectors. These optics, working in the near infrared, are among the best optics ever created and played a crucial role in the first direct detection of gravitational waves from black holes or neutron star fusions.

Scientists have effectively proved that vegetative environment buffers (VEBs) can be used for reducing dust emissions from livestock buildings, but they have seen fewer tests in poultry farms. A field research was conducted to assess the effectiveness of VEBs on reducing downwind transport of particulate matter (PM) from a ventilated poultry house in Changchun. Five plant species transferred from local area were used to establish five diverse VEBs and separately installed outside of the ventilation fans in summer 2017. The five plant species were Winged Euonymus (WE), Malus Spectabilis (MS), Padus Maackii (PAA), Acer Saccharum Marsh (ASM), and Padus Virginiana "Red Select Shrub" (PV&#95;RSS). The mass concentrations of PM 2.5 and PM 10 (particulate matter with an aerodynamic diameter of 2.5 μm and 10 μm or less, respectively) were monitored at downwind and upwind sampling locations around the VEB. The results showed that with the presenting of VEBs, the particle concentrations at the downwind sampling point were significantly reduced compared with that at the upwind sampling point ( p < 0.05). Specifically, compared to the control test without VEB, the VEB with PV&#95;RSS had the best PM concentration reduction rate (CRR) of 47.24%±4.33% and 41.13%±5.83% for PM 2.5 and PM 10 , respectively. The rough surface of plant leaves may help intercept more PM, though it was also affected by other factors (such as the blade angle, the interaction with wind) needed to be further investigated. The VEB with PV&#95;RSS, which presented the best capacity of CRR, selectively intercepted PM, mainly related to the elements of N, Na, Mg, P, S, and Cl. Implications : Five plant species, including WE, PAA, MS, ASM, and PV&#95;RSS, were evaluated as VEBs to mitigate particulate emissions from outside of a ventilated poultry house in Changchun. They all significantly reduced particulate matter emissions. However, the PV&#95;RSS presented the best capability of trapping fine and coarse particles: PM 2.5 and PM 10 , respectively, while the PAA was the worst one. The microstructure of leaves affected particle deposition and remaining on the leaves, and PV&#95;RSS selectively intercepted particulate matter mainly related to certain elements.

Vietnam and Indonesia have rapidly growing and extensive plantation forestry programs, especially of Acacia spp. and Eucalyptus spp. As these plantations expand, the threat from pests and diseases also increases. Calonectria species are among those pathogens causing diseases of trees in plantations and nurseries in these countries. Extensive surveys were conducted across plantations and nurseries of Vietnam and parts of Indonesia, where a large number of Calonectria isolates were retrieved from diseased leaves and soils associated with symptomatic trees. The aim of this study was to identify and resolve the phylogenetic relationships among these isolates using DNA sequence comparisons of four gene regions as well as morphological characters. From a collection of 165 isolates, the study revealed five known and 10 undescribed species. The relatively high diversity of Calonectria species found in this study supports the view that many more species in this genus remain to be discovered in other areas of Southeast Asia.

Background: Patients with cirrhosis are at high risk of hepatocellular carcinoma (HCC). The SEPT9 gene is a key regulator of cell division and tumor suppressor whose hypermethylation is associated with liver carcinogenesis. The primary aim of this study was to evaluate the diagnostic accuracy of a PCR-based assay for the analysis of SEPT9 promoter methylation in circulating cell-free DNA (mSEPT9) for diagnosing HCC among cirrhotic patients., Methods: We report two phase II biomarker studies that included cirrhotic patients with or without HCC from France (initial study) and Germany (replication study). All patients received clinical and biological evaluations, and liver imaging according to current recommendations. The primary outcome was defined as the presence of HCC according to guidelines from the American Association for the Study of Liver Diseases. The diagnosis of HCC was confirmed by abdominal contrast-enhanced computed tomography scan and systematically discussed in a multidisciplinary consultation meeting. HCC-free cirrhotic patients were recruited if the screening abdominal ultrasound showed no evidence of HCC at the time of blood sampling for the mSEPT9 test and on the next visit six months later. The adjudicating physicians were blinded to patient results associated with the mSEPT9 test., Findings: We included 289 patients with cirrhosis (initial: 186; replication: 103), among whom 98 had HCC (initial: 51; replication: 47). The mSEPT9 test exhibited high diagnostic accuracy for HCC diagnosis, with an area under the receiver operating characteristic curve (AUROC) of 0.944 (0.900-0.970, p<0.0001) in the initial study (replication: 0.930 [0.862-0.971, p<0.0001]; meta-analysis: AUROC=0.940 [0.910-0.970, p<0.0001], no heterogeneity: I 2 =0%, p=0.67; and no publication bias). In multivariate logistic regression analysis, the number of positive mSEPT9 triplicates was the only independent variable significantly associated with HCC diagnosis (initial: OR=6.30, for each mSEPT9 positive triplicate [2.92-13.61, p<0.0001]; replication: OR=6.07 [3.25-11.35, p<0.0001]; meta-analysis: OR=6.15 [2.93-9.38, p<0.0001], no heterogeneity: I 2 =0%, p=0.95; no publication bias). AUROC associated with the discrimination of the logistic regression models in initial and validation studies were 0.969 (0.930-0.989) and 0.942 (0.878-0.978), respectively, with a pooled AUROC of 0.962 ([0.937-0.987, p<0.0001], no heterogeneity: I 2 =0%, p=0.36; and no publication bias)., Interpretation: Among patients with cirrhosis, the mSEPT9 test constitutes a promising circulating epigenetic biomarker for HCC diagnosis at the individual patient level. Future prospective studies should assess the mSEPT9 test in the screening algorithm for cirrhotic patients to improve risk prediction and personalized therapeutic management of HCC., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Given their excellent optical and mechanical properties, substrate-transferred crystalline coatings are an exciting alternative to amorphous multilayers for applications in precision interferometry. The high mechanical quality factor of these single-crystal interference coatings reduces the limiting thermal noise in precision optical instruments such as reference cavities for narrow-linewidth laser systems and interferometric gravitational wave detectors. In this manuscript, we explore the optical performance of GaAs/AlGaAs crystalline coatings transferred to 50.8-mm (2-inch) diameter fused silica and sapphire substrates. We present results for the transmission, scattering, absorption, and surface quality of these prototype samples including the defect density and micro-roughness. These novel coatings exhibit optical performance on par with state-of-the-art dielectric structures, encouraging further work focused on the fabrication of larger optics using this technique.

For the first time, direct detection of gravitational waves occurred in the Laser Interferometer Gravitational-wave Observatory (LIGO) interferometers. These advanced detectors require large fused silica mirrors with optical and mechanical properties and have never been reached until now. This paper details the main achievements of these ion beam sputtering coatings.

Over the past several years there has been an increased number of applications of cellulosic materials in many sectors, including the food industry, cosmetics, and pharmaceuticals. However, to date, there are few studies investigating the potential adverse effects of cellulose nanocrystals (CNC). The objective of this study was to determine long-term outcomes on the male reproductive system of mice upon repeated pharyngeal aspiration exposure to CNC. To achieve this, cauda epididymal sperm samples were analyzed for sperm concentration, motility, morphological abnormalities, and DNA damage. Testicular and epididymal oxidative damage was evaluated, as well as histopathology examination of testes. In addition, changes in levels of testosterone in testes and serum and of luteinizing hormone (LH) in serum were determined. Three months after the last administration, CNC exposure significantly altered sperm concentration, motility, cell morphology, and sperm DNA integrity. These parameters correlated with elevated proinflammatory cytokines levels and myeloperoxidase (MPO) activity in testes, as well as oxidative stress in both testes and epididymis. Exposure to CNC also produced damage to testicular structure, as evidenced by presence of interstitial edema, frequent dystrophic seminiferous tubules with arrested spermatogenesis and degenerating spermatocytes, and imbalance in levels of testosterone and LH. Taken together, these results demonstrate that pulmonary exposure to CNC induces sustained adverse effects in spermatocytes/spermatozoa, suggesting male reproductive toxicity., Competing Interests: No conflict of interest relevant to this article is present.

Objective: This study evaluates the cost-effectiveness of memantine extended release (ER) as an add-on therapy to acetylcholinesterase inhibitor (AChEI) [combination therapy] for treatment of patients with moderate-to-severe Alzheimer's disease (AD) from both a healthcare payer and a societal perspective over 3 years when compared to AChEI monotherapy in the US., Methods: A phase III trial evaluated the efficacy and safety of memantine ER for treatment of AD patients taking an AChEI. The analysis assessed the long-term costs and health outcomes using an individual patient simulation in which AD progression is modeled in terms of cognition, behavior, and functioning changes. Input parameters are based on patient-level trial data, published literature, and publicly available data sources. Changes in anti-psychotic medication use are incorporated based on a published retrospective cohort study. Costs include drug acquisition and monitoring, total AD-related medical care, and informal care associated with caregiver time. Incremental cost-utility ratio (ICUR), life years, care time for caregiver, time in community and institution, time on anti-psychotics, time by disease severity, and time without severe symptoms are reported. Costs and health outcomes are discounted at 3% per annum., Results: Considering a societal perspective over 3 years, this analysis shows that memantine ER combined with an AChEI provides better clinical outcomes and lower costs than AChEI monotherapy. Discounted average savings were estimated at $18,355 and $20,947 per patient and quality-adjusted life-years (QALYs) increased by an average of 0.12 and 0.13 from a societal and healthcare payer perspective, respectively. Patients on combination therapy spent an average of 4 months longer living at home and spend less time in moderate-severe and severe stages of the disease., Conclusion: Combination therapy for patients with moderate-to-severe AD is a cost-effective treatment compared to AChEI monotherapy in the US.

We report on low-frequency measurements of the mechanical loss of a high-quality (transmissivity T<5 ppm at λ(0)=1064 nm, absorption loss <0.5 ppm) multilayer dielectric coating of ion-beam-sputtered fused silica and titanium-doped tantala in the 10-300 K temperature range. A useful parameter for the computation of coating thermal noise on different substrates is derived as a function of temperature and frequency.

We report on the measurement of the optical absorption of bulk crystalline silicon at 1550 nm. Using the photodeflection technique, absorption as low as 5 ppm/cm has been measured on a sample with a resistivity of 10 kΩ·cm. The absorption as a function of the resistivity has been derived for n-type silicon.

Gravitational-wave detectors such as Virgo and the laser interferometric gravitational-wave observatory (LIGO) use a long-baseline Michelson interferometer with Fabry-Perot cavities in the arms to search for gravitational waves. The symmetry between the two Fabry-Perot cavities is crucial to reduce the interferometer's sensitivity to the laser amplitude and frequency noise. To this purpose, the transmittance of the mirrors in both cavities should be as close as possible. This paper describes the realization and the characterization of the first twin large low-loss mirrors with transmissions differing by less than 0.01%.

The new generation of advanced interferometer needs fused silica mirrors having better optical and mechanical properties. This Letter describes the way to reduce the ion beam sputtering coating absorption at 1064 nm and to improve the layer thickness uniformity in order to coat two large mirrors (diameter 35 cm) at the same time.

We have tested a new kind of Fabry-Perot long-baseline optical resonator proposed to reduce the thermal noise sensitivity of gravitational wave interferometric detectors--the "mesa beam" cavity--whose flat top beam shape is achieved by means of an aspherical end mirror. We present the fundamental mode intensity pattern for this cavity and its distortion due to surface imperfections and tilt misalignments, and contrast the higher order mode patterns to the Gauss-Laguerre modes of a spherical mirror cavity. We discuss the effects of mirror tilts on cavity alignment and locking and present measurements of the mesa beam tilt sensitivity.

Cartilaginous fish, primarily sharks, rays and skates (elasmobranchs), appeared 450 million years ago. They are the most primitive vertebrates, exhibiting jaws and teeth, adaptive immunity, a pressurized circulatory system, thymus, spleen, and a liver comparable to that of humans. The most used elasmobranch in biomedical research is the spiny dogfish shark, Squalus acanthias. Comparative genomic analysis of the dogfish shark, the little skate (Leucoraja erincea), and other elasmobranchs have yielded insights into conserved functional domains of genes associated with human liver function, multidrug resistance, cystic fibrosis, and other biomedically relevant processes. While genomic information from these animals is informative in an evolutionary framework, experimental verification of functions of genomic sequences depends heavily on cell culture approaches. We have derived the first multipassage, continuously proliferating cell line of a cartilaginous fish. The line was initiated from embryos of the spiny dogfish shark. The cells were maintained in a medium modified for fish species and supplemented with cell type-specific hormones, other proteins and sera, and plated on a collagen substrate. SAE cells have been cultured continuously for three years. These cells can be transfected by plasmids and have been cryopreserved. Expressed Sequence Tags generated from a normalized SAE cDNA library included a number of markers for cartilage and muscle, as well as proteins influencing tissue differentiation and development, suggesting that SAE cells may be of mesenchymal stem cell origin. Examination of SAE EST sequences also revealed a cartilaginous fish-specific repetitive sequence that may be evidence of an ancient mobile genetic element that most likely was introduced into the cartilaginous fish lineage after divergence from the lineage leading to teleosts.

We have established a cartilaginous fish cell line [Squalus acanthias embryo cell line (SAE)], a mesenchymal stem cell line derived from the embryo of an elasmobranch, the spiny dogfish shark S. acanthias. Elasmobranchs (sharks and rays) first appeared >400 million years ago, and existing species provide useful models for comparative vertebrate cell biology, physiology, and genomics. Comparative vertebrate genomics among evolutionarily distant organisms can provide sequence conservation information that facilitates identification of critical coding and noncoding regions. Although these genomic analyses are informative, experimental verification of functions of genomic sequences depends heavily on cell culture approaches. Using ESTs defining mRNAs derived from the SAE cell line, we identified lengthy and highly conserved gene-specific nucleotide sequences in the noncoding 3' UTRs of eight genes involved in the regulation of cell growth and proliferation. Conserved noncoding 3' mRNA regions detected by using the shark nucleotide sequences as a starting point were found in a range of other vertebrate orders, including bony fish, birds, amphibians, and mammals. Nucleotide identity of shark and human in these regions was remarkably well conserved. Our results indicate that highly conserved gene sequences dating from the appearance of jawed vertebrates and representing potential cis-regulatory elements can be identified through the use of cartilaginous fish as a baseline. Because the expression of genes in the SAE cell line was prerequisite for their identification, this cartilaginous fish culture system also provides a physiologically valid tool to test functional hypotheses on the role of these ancient conserved sequences in comparative cell biology.

Large mirrors (ø350 mm) having extremely low optical loss (absorption, scattering, wavefront) were coated for the VIRGO interferometer. The new generation of mirrors needs to have a better wavefront and lower mechanical loss. To improve the component wavefront, the corrective coating technique was used. By doping the tantalum pentoxide layers, we improved, for the first time to our knowledge, the multilayer mechanical loss. The first results are discussed.

Xiphophorus species, inbred strains, and interspecies hybrids have been used extensively to understand the genesis of melanoma and other types of malignancies. Despite sophisticated studies on the genetics of this model, biological studies have been limited by the availability of characterized cell lines. The authors have established a melanoma-derived cell line, XM, from the most commonly used interspecies hybrid model for studies of the genetics and cell biology of melanoma in Xiphophorus. This line demonstrated a previously unrecognized response to platelet-derived growth factor and exhibited a karyotype that was minimally aneuploid or possibly diploid. XM cells formed pigmented tumor-like masses when injected into zebrafish embryos. Some cells also migrated and exhibited differentiated pigment expression in a manner consistent with normal melanocytes. The XM cell is the first characterized line of known genetic background available for study of the in vitro biology of the Xiphophorus model.

In marine sedimentary habitats, chemoreception is thought to coordinate feeding in many deposit-feeding invertebrates such as polychaetes, snails, and clams. Relatively little is known, however, about the chemosensory structures and mechanism of signal transduction in deposit feeders. Using electron microscopy, confocal laser scanning microscopy (CLSM), and immunohistochemistry, we investigated the structure and function of putative chemosensory cells on the feeding appendages of a deposit-feeding polychaete species, Dipolydora quadrilobata. Tufts of putative sensory cilia were distributed over the prostomium and feeding palps and typically occurred next to pores. Examination of these regions with transmission electron microscopy revealed multiciliated cells with adjacent glandular cells beneath the pores. The sensory cells of prostomium and palps were similar, displaying an abundance of apical mitochondria and relatively short ciliary rootlets. Staining with antiserum against acetylated alpha-tubulin was examined by CLSM, and revealed axonal processes from putative sensory tufts on the palp surface to palp nerves, as well as many free nerve endings. Activity-dependent cell labeling experiments were used to test the sensitivity of putative sensory cells on the palps to an amino acid mixture that elicited feeding in previous behavioral experiments. In static exposures, the number of lateral and abfrontal cells labeled in response to the amino acid mixture was significantly greater than in the controls. Ultrastructural, positional, and now physiological evidence strongly suggests that spionid feeding palps are equipped with sensory cells, at least some of which function as chemoreceptors.

Electrical dental anesthesia has recently been suggested as an alternative to local anesthetics for the control of pain related to certain dental acts. This article updates the evidence which supports the efficiency, indications and contra-indications of such a procedure. Although this technique has certain advantages, its use is limited by: 1) how cooperative the patient may be; 2) the time required to explain the procedure to the patient and that which is required to produce the needed clinical effect; and, 3) how efficient it may be relative to the patient in question and the dental treatment rendered.

The radiopacity of glass ionomer dental materials is quite variable. The use of a poorly radiopaque material as a base under other restorative materials can mislead the dentist to a diagnosis of recurrent decay. This study investigates the radiopacity of these materials and proposes a minimal radiopacity under which a material should not be used as a base or liner. All base, liner, and core formulations of glass ionomer under investigation were more radiopaque than dentin. All restorative and luting formulations of glass ionomer under investigation were less radiopaque than dentin and therefore should be avoided as bases or liners.

This article relates to the technique of computerized tomography. New indications for this technique are described and especially those used in implantology. Several axial and coronal sections are presented.

Reverse-phase thin-layer chromatography of 18 common mycotoxins was carried out on Merck C18 and Whatman C18 and diphenyl bonded phases. The mobile phases included neutral and acidified binary mixtures of water and methanol, acetonitrile or tetrahydrofuran. Mycotoxins studied included aflatoxins B1, B2, G1, G2, sterigmatocystin, ochratoxin A, citrinin, penicillic acid, patulin, zearalenone, and the trichothecenes diacetoxyscirpenol, HT-2 toxin, nivalenol, neosolaniol, fusarenone-X, T-2 toxin, deoxynivalenol and 3-acetyl-deoxynivalenol. Both C18-bonded phases performed well, and could serve as a convenient confirmation for mycotoxins appearing in normal-phase (silica) thin-layer chromatographic screening procedures.