24 research outputs found

    Ptychographic X-ray tomography reveals additive zoning in nanocomposite single crystals

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    Single crystals containing nanoparticles represent a unique class of nanocomposites whose properties are defined by both their compositions and the structural organization of the dispersed phase in the crystalline host. Yet, there is still a poor understanding of the relationship between the synthesis conditions and the structures of these materials. Here ptychographic X-ray computed tomography is used to visualize the three-dimensional structures of two nanocomposite crystals – single crystals of calcite occluding diblock copolymer worms and vesicles. This provides unique information about the distribution of the copolymer nano-objects within entire, micron-sized crystals with nanometer spatial resolution and reveals how occlusion is governed by factors including the supersaturation and calcium concentration. Both nanocomposite crystals are seen to exhibit zoning effects that are governed by the solution composition and interactions of the additives with specific steps on the crystal surface. Additionally, the size and shape of the occluded vesicles varies according to their location within the crystal, and therefore the solution composition at the time of occlusion. This work contributes to our understanding of the factors that govern nanoparticle occlusion within crystalline materials, where this will ultimately inform the design of next generation nanocomposite materials with specific structure/property relationships

    Diagnostic and prognostic value of noninvasive long-term video-electroencephalographic monitoring in epilepsy surgery: A systematic review and meta-analysis from the E-PILEPSY consortium

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    OBJECTIVE: The European Union–funded E‐PILEPSY network (now continuing within the European Reference Network for rare and complex epilepsies [EpiCARE]) aims to harmonize and optimize presurgical diagnostic procedures by creating and implementing evidence‐based guidelines across Europe. The present study evaluates the current evidence on the diagnostic accuracy of long‐term video‐electroencephalographic monitoring (LTM) in identifying the epileptogenic zone in epilepsy surgery candidates. METHODS: MEDLINE, Embase, CENTRAL, and ClinicalTrials.gov were searched for relevant articles. First, we used random‐effects meta‐analytical models to calculate pooled estimates of sensitivity and specificity with respect to postsurgical seizure freedom. In a second phase, we analyzed individual patient data in an exploratory fashion, assessing diagnostic accuracy within lesional and nonlesional temporal lobe epilepsy (TLE) and extratemporal lobe epilepsy (ETLE) patients. We also evaluated seizure freedom rate in the presence of “localizing” or “nonlocalizing” LTM within each group. The quality of evidence was assessed using the QUADAS‐2 tool and the GRADE approach. RESULTS: Ninety‐four studies were eligible. Forty‐four were included in sensitivity meta‐analysis and 34 in specificity meta‐analysis. Pooled sensitivity was 0.70 (95% confidence interval [CI] = 0.60‐0.80) and specificity was 0.40 (95% CI = 0.27‐0.54). Subgroup analysis was based on individual data of 534 patients (41% men). In lesional TLE patients, sensitivity was 0.85 (95% CI = 0.81‐0.89) and specificity was −0.19 (95% CI = 0.13‐0.28). In lesional ETLE patients, a sensitivity of 0.47 (95% CI = 0.36‐0.58) and specificity of 0.35 (95% CI = 0.21‐0.53) were observed. In lesional TLE, if LTM was localizing and concordant with resection site, the seizure freedom rate was 247 of 333 (74%), whereas in lesional ETLE it was 34 of 56 (61%). The quality of evidence was assigned as “very low.” SIGNIFICANCE: Long‐term video‐electroencephalographic monitoring is associated with moderate sensitivity and low specificity in identification of the epileptogenic zone. Sensitivity is remarkably higher in lesional TLE compared to lesional ETLE. Substantial heterogeneity across the studies indicates the need for improved design and quality of reporting

    Funktionelle Ergebnisse nach transmandibulärer Resektion und primärer Radiochemotherapie bei fortgeschrittenen Kopf-Hals-Plattenepithelkarzinomen

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    Objective!#!The aim of this study was to assess the functional outcome after transmandibular resection and reconstruction via a radial forearm flap (TMR+RFF) compared to primary chemoradiotherapy (pCRT) in advanced oropharyngeal squamous cell carcinoma (OPSCC).!##!Methods!#!The study compared 50 OPSCC patients treated with TMR+RFF to 50 OPSCC patients receiving pCRT. The time taken to swallow water served as the primary endpoint. The Saxon test, maxillomandibular distance, Mallampati score, ratio of height to weight, nasal penetration, tracheostomy/gastral tube requirement, and four validated questionnaires (visual analog scale for xerostomia, Sicca VAS; MD Anderson Dysphagia Inventory, MDADI; Voice Handicap Index, VHI; European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, Head and Neck Cancer, 35 items, QLQ-H&N35) were applied to access functionality and quality of life.!##!Results!#!Patients after TMR+RFF showed an increased rate of nasal penetration (p < 0.0001), which was associated with a longer water swallowing time (p < 0.05). A modified reconstruction of the soft palate significantly decreased the rate of nasal penetration in comparison to classical reconstruction (p = 0.0001). Patients with pCRT suffered significantly more xerostomia (Saxon test) than patients with TMR+RFF and adjuvant therapy. None of the subjective questionnaires revealed significant differences between the groups.!##!Conclusion!#!TMR+RFF with modified reconstruction and adjuvant treatment and pCRT showed comparable functional outcomes

    High-acceptance versatile microfocus module based on elliptical Fresnel zone plates for small-angle X-ray scattering

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    High-efficiency microfocusing of multi-keV X-rays at synchrotron sources is highly profitable for spatially resolved structural analysis of many kinds. Because radiation from synchrotron sources is typically elongated along the horizontal dimension, generating a microbeam that is isotropic in size requires a carefully designed optics system. Here we report on using a combination of a horizontally tunable slit downstream of the undulator source with elliptical diffractive Fresnel zone plates. We demonstrate the arrangement in context of small-angle X-ray scattering experiments, obtaining a microbeam of 2.2 μm ×1.8 μm (X × Y) with a flux of 1.2 × 1010 photons/s at an energy of 11.2 keV at the sample position

    New Human Tumor Cell Lines

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