Resolution of Virtual Depth Sectioning from Four-Dimensional Scanning Transmission Electron Microscopy.

One approach to three-dimensional structure determination using the wealth of scattering data in four-dimensional (4D) scanning transmission electron microscopy (STEM) is the parallax method proposed by Ophus et al. (2019. Advanced phase reconstruction methods enabled by 4D scanning transmission electron microscopy, Microsc Microanal25, 10-11), which determines the scattering matrix and uses it to synthesize a virtual depth-sectioning reconstruction of the sample structure. Drawing on an equivalence with a hypothetical confocal imaging mode, we derive contrast transfer and point spread functions for this parallax method applied to weakly scattering objects, showing them identical to earlier depth-sectioning STEM modes when only bright field signal is used, but that improved depth resolution is possible if dark field signal can be used. Through a simulation-based study of doped Si, we show that this depth resolution is preserved for thicker samples, explore the impact of shot noise on the parallax reconstructions, discuss challenges to making use of dark field signal, and identify cases where the interpretation of the parallax reconstruction breaks down.

A population-based epidemiological study of neuromyelitis optica spectrum disorder in Hungary.

BACKGROUND AND PURPOSE: The goal of this study was to determine the prevalence and incidence of neuromyelitis optica spectrum disorder (NMOSD) in Hungary based on the 2015 International Panel of NMO Diagnosis (IPND) criteria. METHODS: A retrospective population-based cohort study was conducted of 6.4 million Hungarians (age ≥ 16 years) between 1 January 2006 and 31 December 2016. Possible NMOSD patients were selected via multistage re-evaluation from multiple sources. Crude and sex- and serostatus-specific prevalence (per 100 000 persons) and incidence rates (per 1 000 000 person-years) from 2006 to 2015 were estimated and age-adjusted rates were determined. RESULTS: Of 2262 study candidates, 154 NMOSD patients (age ≥ 16 years) with onset until 31 December 2016 were identified based on 2015 IPND criteria. The prevalence analysis on 1 January 2016 included 123 NMOSD living cases, resulting in a prevalence of 1.91 [95% confidence interval (CI) 1.52-2.28] per 100 000 persons. The 101 incident cases emerging from the observed 76 394 288 person-years provided an incidence rate of 1.32 (95% CI 1.08-1.61) per 1 000 000 person-years. Age-adjusted prevalence was 1.87 (95% CI 1.56-2.23) per 100 000 persons and incidence was 1.20 (95% CI 0.98-1.46) per 1 000 000 person-years. CONCLUSIONS: In this first report of a large population-based epidemiological study from an Eastern European Caucasian population using robust case validation, a greater prevalence and incidence of NMOSD was found compared to previous large studies in Caucasian populations.

Braiding and Fusion of Non-Abelian Vortex Anyons.

We have studied topology and dynamics of quantum vortices in spin-2 Bose-Einstein condensates. By computationally modeling controllable braiding and fusion of these vortices, we have demonstrated that certain vortices in such spinor condensates behave as non-Abelian anyons. We identify these anyons as fluxon, chargeon, and dyon quasiparticles. The pertinent anyon models are defined by the quantum double of the underlying discrete non-Abelian symmetry group of the condensate ground state order parameter.

Simple Wave-Optical Superpositions as Prime Number Sieves.

We encode the sequence of prime numbers into simple superpositions of identical waves, mimicking the archetypal prime number sieve of Eratosthenes. The primes are identified as zeros accompanied by phase singularities in a physically generated wave field for integer valued momenta. Similarly, primes are encoded in the diffraction pattern from a simple single aperture and in the harmonics of a single vibrating resonator. Further, diffraction physics connections to number theory reveal how to encode all Gaussian primes, twin primes, and how to construct wave fields with amplitudes equal to the divisor function at integer spatial frequencies. Remarkably, all of these basic diffraction phenomena reveal that the naturally irregular sequence of primes can arise from trivially ordered wave superpositions.

Vacancy induced formation of nanoporous silicon, carbon and silicon carbide.

Nanoporous semiconductors are used in a range of applications from sensing and gas separation, to photovoltaics, rechargeable batteries, energetic materials and micro electro mechanical systems. In most cases porosity occurs in conjunction with the competing process of amorphisation, creating a complicated material that responds differently to strain and density changes, depending on the composition. In this paper we use simple computational workflow involving Monte Carlo simulation, numerical characterisation and statistical analysis to explore the development of amorphous and nanoporous carbon, silicon and silicon carbide. We show that amorphous regions in Si and SiC form in advance of nanopores, and are essential in stabilising the nanopores once developed. Carbon prefers a porous structure at lower strains than amorphisation and exhibits a bimodal change in the structure which correlates with the change in C-C bond angles from tetrahedral sp3-like bonds to hexagonal sp2-like bonds as the strain increases. These results highlight how both of these processes can be analysed simultaneously using reliable interatomic forcefields or density functionals, provided sufficient samples are included to support the statistics.

Myocardial injury and mortality in patients with excessive oxygen administration before cardiac arrest.

INTRODUCTION: Hyperoxia after cardiac arrest may be associated with higher mortality, and trials have found that excess oxygen administration in patients with myocardial infarction is associated with increased infarct size. The effect of hyperoxia before cardiac arrest is sparsely investigated. Our aim was to assess the association between excessive oxygen administration before cardiac arrest and the extent of subsequent myocardial injury. METHODS: We performed a retrospective study including patients who had in-hospital cardiac arrest during 2014 in the Capital Region of Denmark. We excluded patients without peripheral oxygen saturation measurements within 48 hours before cardiac arrest. Patients were divided in three groups of pre-arrest oxygen exposure, based on average peripheral oxygen saturation and supplemental oxygen. Primary outcome was peak troponin concentration within 30 days. Secondary outcomes included 30-day mortality. Data were analyzed using multiple logistic regression and Wilcoxon rank sum test. RESULTS: Of 163 patients with cardiac arrest, 28 had excessive oxygen administration (17%), 105 had normal oxygen administration (64%) and 30 had insufficient oxygen administration (18%) before cardiac arrest. Peak troponin was median 224 ng/L in the excessive oxygen administration group vs 365 ng/L in the normal oxygen administration group (P = .54); 20 of 28 (71%) in the excessive oxygen administration group died within 30 days compared to 54 of 105 (51%) in the normal oxygen administration group. (OR 1.87, 95% CI 0.56-6.19) CONCLUSIONS: Excessive oxygen administration within 48 hours before in-hospital cardiac arrest was not statistically associated with significantly higher peak troponin or mortality.

Structural brain maturation differs between preterm and term piglets, whereas brain activity does not.

AIM: The aim of the study was to investigate whether amplitude-integrated electroencephalography (aEEG) and cerebral magnetic resonance imaging (MRI) in preterm piglets would provide measures of cerebral functional, microstructural and anatomical maturation, which might reflect the signs of functional brain immaturity, documented in preterm piglets. METHODS: During July-October 2013 at the NEOMUNE Centre, Copenhagen University, Denmark, 31 preterm (90% gestation) and 10 term piglets underwent aEEG on days 1, 2, 4 and 11, and MRI on day 25. Physical activity levels were recorded. RESULTS: Preterm showed delayed neonatal arousal and physical activity, relative to term piglets. Preterm piglets had lower growth rates and brain volume than term piglets, but aEEG patterns were similar. MRI mean diffusivity was also similar, but fractional anisotropy (FA) was lower in preterm piglets (p < 0.001). CONCLUSION: Functional brain maturation, as assessed by aEEG, was relatively advanced in preterm piglets. Conversely, the low FA in the preterm piglets suggests that the white matter microstructure remains less mature in preterm compared to term piglets at postnatal day 25. The results might be utilised to define whether and how preterm piglets may contribute to preclinical models for brain development in preterm infants.

Higher chlorzoxazone clearance in obese children compared with nonobese peers.

AIMS: To test the in vivo activity of Cytochrome P450 (CYP) 2E1 in obese children vs. nonobese children, aged 11-18 years. Secondly, whether the activity of CYP2E1 in these patients is associated with NALFD, diabetes or hyperlipidaemia. METHODS: Seventy children were divided into groups by body mass index (BMI) standard deviation score (SDS). All children received 250 mg oral chlorzoxazone (CLZ) as probe for CYP2E1 activity. Thirteen blood samples and 20-h urine samples were collected per participant. RESULTS: Obese children had an increased oral clearance and distribution of CLZ, indicating increased CYP2E1 activity, similar to obese adults. The mean AUC0-∞ value of CLZ was decreased by 46% in obese children compared to nonobese children. The F was was increased twofold in obese children compared to nonobese children, P < 0.0001. Diabetic biomarkers were significantly increased in obese children, while fasting blood glucose and Hba1c levels were nonsignificant between groups. Liver fat content was not associated with CLZ Cl. CONCLUSION: Oral clearance of CLZ was increased two-fold in obese children vs. nonobese children aged 11-18 years. This indicates an increased CYP2E1 activity of clinical importance, and dose adjustment should be considered for CLZ.

Incidence of neuromyelitis optica spectrum disorder in the Central Denmark Region.

OBJECTIVES: Neuromyelitis optica (NMO)/NMO spectrum disorder (NMOSD) may be misdiagnosed as multiple sclerosis. The aim of this study was to (i) to measure AQP4-IgG in patients who fulfilled the clinical and radiological criteria of NMOSD in the Central Denmark Region and (ii) to estimate the incidence of NMOSD in the region, according to both the 2006 Wingerchuk criteria and the 2015 International Panel for NMO Diagnosis criteria. MATERIALS AND METHODS: Medical records of all patients diagnosed with a demyelinating disorder in the region from 1 January 2012 to 31 December 2013 were reviewed. Patients were classified as having (i) "NMO" if the 2006 criteria were met, (ii) "NMOSD with AQP4-IgG" or (iii) "NMOSD without/unknown AQP-IgG" if the new 2015 NMOSD criteria were met. Patients with core symptoms were invited to provide a blood sample for AQP4-IgG analysis with an enzyme-linked immunosorbent assay and a cell-based indirect immunofluorescence assay. RESULTS: In 191 patients with core symptoms, one met the 2015 NMOSD with AQP4-IgG criteria. Two patients met the 2006 NMO and 2015 NMOSD without/unknown AQP4-IgG criteria. Among 108 patients providing a blood sample, all were seronegative. The estimated incidence of NMO (2006 criteria) and NMOSD (2015 criteria) was 0.08 and 0.12 per 100 000 person-years, respectively. CONCLUSION: NMO/NMOSD is a rare disease in the Central Denmark Region, with a considerably lower incidence rate than previously estimated in a neighbouring region.

High-average-power, 2-µm femtosecond optical parametric oscillator synchronously pumped by a thin-disk, mode-locked laser.

A high-energy, extended-cavity femtosecond BiBO optical parametric oscillator synchronously pumped by a 1.0-ps, 1030-nm Yb:YAG, thin-disk pump laser is presented. The oscillator operated near degeneracy in a noncollinear interaction geometry, producing signal wavelength tunability from 1.99 to 2.20 µm. The signal pulses have an average power exceeding 2 W, producing 455-fs pulses at 7.08 MHz with energies up to 350 nJ, showing increased potential for tunable sources of scalable ultrafast pulses in the infrared.

Cross-reactivity between methylisothiazolinone, octylisothiazolinone and benzisothiazolinone using a modified local lymph node assay.

BACKGROUND: In the light of the exceptionally high rates of contact allergy to the preservative methylisothiazolinone (MI), information about cross-reactivity between MI, octylisothiazolinone (OIT) and benzisothiazolinone (BIT) is needed. OBJECTIVES: To study cross-reactivity between MI and OIT, and between MI and BIT. METHODS: Immune responses to MI, OIT and BIT were studied in vehicle and MI-sensitized female CBA mice by a modified local lymph node assay. The inflammatory response was measured by ear thickness, cell proliferation of CD4+ and CD8+ T cells, and CD19+ B cells in the auricular draining lymph nodes. RESULTS: MI induced significant, strong, concentration-dependent immune responses in the draining lymph nodes following a sensitization phase of three consecutive days. Groups of MI-sensitized mice were challenged on day 23 with 0·4% MI, 0·7% OIT and 1·9% BIT - concentrations corresponding to their individual EC3 values. No statistically significant difference in proliferation of CD4+ and CD8+ T cells was observed between mice challenged with MI compared with mice challenged with BIT and OIT. CONCLUSIONS: The data indicate cross-reactivity between MI, OIT and BIT, when the potency of the chemical was taken into account in choice of challenge concentration. This means that MI-sensitized individuals may react to OIT and BIT if exposed to sufficient concentrations.

Thermal effects in an ultrafast BiB3O6 optical parametric oscillator at high average powers.

An ultrafast, high-average-power, extended-cavity, femtosecond BiB3O6 optical parametric oscillator was constructed as a test bed for investigating the scalability of infrared parametric devices. Despite the high pulse energies achieved by this system, the reduction in slope efficiency near the maximum-available pump power prompted the investigation of thermal effects in the crystal during operation. The local heating effects in the crystal were used to determine the impact on both phase matching and thermal lensing to understand limitations that must be overcome to achieve microjoule-level pulse energies at high repetition rates.

Effect of specimen orientation on the accuracy of vector field electron tomography.

Vector field electron tomography (VFET) reconstructs vector fields based on phase maps recorded from two or more orthogonal tilt series. The tomographic reconstruction of vector fields involves considerations beyond those involved in the reconstruction of scalar fields. Here we examine the effect of initial magnetization orientation on reconstruction errors. The orientation of a magnetic particle affects the contrast in the phase maps. This, in turn, affects the accuracy of the reconstructed vector fields. We derive expressions that model the dependence of reconstruction errors on initial specimen orientation when using a filtered backprojection algorithm to reconstruct a vector potential from two tilt series. We compare these analytical results with those from numerical simulations. Our results can inform experimental procedures, such as sample preparation techniques and the choice of tilt series orientations. Specimen orientation can be a significant source of error in VFET, and our results can provide the means to minimize these errors.

Publisher's Note: Calculation of Projected Bond-Orientational Order Parameters to Quantify Local Symmetries from Transmission Diffraction Data [Phys. Rev. Lett. 116, 205501 (2016)].

This corrects the article DOI: 10.1103/PhysRevLett.116.205501.

Calculation of Projected Bond-Orientational Order Parameters to Quantify Local Symmetries from Transmission Diffraction Data.

The bond-orientational order parameters introduced by Steinhardt et al. [Phys. Rev. B 28, 784 (1983)] have been an invaluable measurement tool for assessing short-range order in disordered, close-packed assemblies of particles in which the particle positions are known. In many glassy systems the measurement of particle position is not possible or limited (field of view, thickness, resolution) and the bond-orientational order parameters cannot be measured, or adequately sampled. Here we calculate a set of rotationally averaged, projected bond-orientational order parameters that reflect the symmetries of close-packed particle clusters when projected onto a plane. We show by simulation that these parameters are unique fingerprints that can be directly compared to angular correlations in limited-volume, transmission geometry, diffraction patterns from close-packed glassy assemblies.

Epidermal filaggrin deficiency mediates increased systemic T-helper 17 immune response.

BACKGROUND: Cellular T-helper (Th)17 infiltrates dominate skin inflammation in filaggrin-deficient flaky tail (ft/ft) mice, and Th17 cells are found in both the skin and blood of patients with acute atopic dermatitis. However, the potential role of loss-of-function mutations in the filaggrin gene (FLG) for increased peripheral Th17 cells is unclear. OBJECTIVES: To study whether mutations in FLG influence the frequency of peripheral Th17 cells. METHODS: We studied blood samples from six adults with mutations in FLG and five controls without mutations for frequencies of cytokine-producing CD4(+) T cells. We evaluated ft/ft mice and wild-type (WT) control mice for interleukin (IL)-17-producing CD4(+) T cells in naive mice and following 2,4-dinitrofluorobenzene (DNFB) challenge. In addition, the T-cell receptor (TCR) Vß-chain repertoire was analysed by flow cytometry. RESULTS: Human studies showed increased frequency of peripheral Th17 cells in FLG mutation carriers when compared with WT individuals. Mouse studies showed increased frequency of peripheral Th17 cells in adult ft/ft mice but not in 2-week-old ft/ft mice. Moreover, altered TCR Vß-chain repertoire was found in ft/ft mice when compared with WT mice. An increased frequency of CD4(+) Vß10(+) T cells producing IL-17 was found in the spleen of adult ft/ft mice when compared with WT mice. Finally, DNFB challenge induced an increased number of Th17 cells in ft/ft mice compared with WT mice. CONCLUSIONS: Deficiency of filaggrin appeared to be a driver of increased peripheral levels of Th17 cells. This increase must be acquired as peripheral Th17 cells were found in adult ft/ft mice but not in 2-week-old ft/ft mice indicating involvement of exogenous factors.

Acute and chronic cytokine responses to resistance exercise and training in people with multiple sclerosis.

Exercise is a well-established part of rehabilitation for people with multiple sclerosis (PwMS), and it has been hypothesized to stimulate an anti-inflammatory environment that might be disease modifying. Yet, investigations on exercise-induced immune responses are scarce and generally not paying attention to the medical treatments of the patient. At present, PwMS are routinely enrolled in immunosuppressive medication, but exercise-induced immunomodulatory effects have not been investigated under these circumstances. The objective of this study was to investigate the acute and chronic cytokines responses to resistance exercise training in medicated PwMS. Thirty-five people with relapsing-remitting multiple sclerosis (MS) treated with interferon (IFN)-ß, were randomized to a 24-week progressive resistance training (PRT) or control group. Plasma interleukin (IL)-1ß, IL-4, IL-10, IL-17F, IL-23, tumor necrosis factor-α and IFN-γ were measured before and after 24 weeks of PRT. The acute effect was evaluated following standardized single-bout resistance exercise in the untrained and the trained state. No changes were observed in resting cytokine levels after PRT. However, an indication of reduced IL-17F secretion following resistance exercise was observed in the trained compared with the untrained state. This study suggests little acute and chronic effect of PRT on cytokine levels in IFN-treated PwMS.

Recovery of Arapaima sp. populations by community-based management in floodplains of the Purus River, Amazon.

In the present study a unique dataset on population abundance in various community-based management (CBM) and non-CBM areas is analysed to address the question of whether CBM can recover overexploited populations of Arapaima sp. in river-floodplain ecosystems. All non-CBM areas possessed depleted Arapaima sp. populations with a mean density of 0·01 individuals ha(-1) . Arapaima sp. population densities in all CBM areas changed over time from depleted to overexploited or well managed status, with a mean rate of increase of 77% year(-1) . Rates of Arapaima sp. population recovery in CBM areas differed, probably reflecting differences in ecosystem productivity and compliance with management regulations. These results indicate that CBM schemes can be effective tools for the recovery and conservation of fish populations with non-migratory life cycles in tropical river-floodplain ecosystems.

Proteolytic processing of anti-Müllerian hormone differs between human fetal testes and adult ovaries.

From early embryonic life, anti-Müllerian hormone (AMH) is produced by Sertoli cells and is essential for male sex differentiation. In females, AMH is produced by immature granulosa cells (GCs) but a definitive function in females is uncertain. We have assessed the cellular localization and specificity of a panel of five novel high-affinity AMH monoclonal antibodies. Two recognize the mature C-terminal form of AMH, whereas three recognize the active pro-mature form of AMH in human tissue. The antibodies were tested on fetal male testicular and mesonephric tissue aged 8-19 weeks post conception (pc), fetal male serum aged 16-26 weeks pc and human immature GCs by immunofluorescence, immunohistochemistry, ELISA and western blotting. The active pro-mature forms of AMH were expressed in both Sertoli cells from human fetal testis and human immature GCs. In contrast, the mature C-terminal form of AMH was hardly detected in Sertoli cells, but was readily detected in GCs. This particular form was also located to the nucleus in GCs, whereas the other investigated AMH forms remained in the cytoplasm. Interestingly, the distribution of the AMH forms in the fetal serum of boys showed that the fraction of inactive precursor AMH only accounted for 4.5% ± 0.6 (mean ± SD) of the total AMH measured, and the remaining AMH was the active pro-mature form. Furthermore, western blot analysis demonstrated a number of previously unrecognized molecular forms of AMH. The present findings suggest that processing of AMH is a tightly regulated process, which is likely to be important for the function of AMH and which differs between the two sexes.

Ethyl-Zinc(II)-Cation Equivalents: Synthesis and Hydroamination Catalysis.

Ion-like ethylzinc(II) compounds with weakly coordinating aluminates [Al(OR(F))4](-) and [(R(F)O)3Al-F-Al(OR(F))3](-) (R(F)=C(CF3)3) were synthesized in a one-pot reaction and fully characterized by single-crystal X-ray diffraction, NMR and vibrational spectroscopy, and by quantum chemical calculations. The catalytic activity of ion-like Et-Zn[Al(OR(F))4] in intermolecular hydroamination and in the unusual double hydroamination of anilines and alkynes was investigated. Favorable performance was also found in comparison to the Et2Zn/[PhNMe2H](+)[B(C6F5)4](-) system generated in situ at lower catalyst loadings of 2.5 mol %.