Josef Anton Bruckner (German: [ˈantɔn ˈbʁʊknɐ] (listen); (1824-09-04)4 September 1824 – (1896-10-11)11 October 1896) was an Austrian composer, organist, and music theorist best known for his symphonies, Masses, Te Deum and motets. The first are considered emblematic of the final stage of Austro-German Romanticism because of their rich harmonic language, strongly polyphonic character, and considerable length. Bruckner's compositions helped to define contemporary musical radicalism, owing to their dissonances, unprepared modulations, and roving harmonies. Unlike other musical radicals such as Richard Wagner and Hugo Wolf, Bruckner showed extreme humility before other musicians, Wagner in particular. This apparent dichotomy between Bruckner the person and Bruckner the composer hampers efforts to describe his life in a way that gives a straightforward context for his music. Hans von Bülow described him as "half genius, half simpleton". Bruckner was critical of his own work and often reworked his compositions. There are several versions of many of his works. His works, the symphonies in particular, had detractors, most notably the influential Austrian critic Eduard Hanslick and other supporters of Johannes Brahms, who pointed to their large size and use of repetition, as well as to Bruckner's propensity for revising many of his works, often with the assistance of colleagues, and his apparent indecision about which versions he preferred. On the other hand, Bruckner was greatly admired by subsequent composers, including his friend Gustav Mahler.
Taylor's law, originally formulated in ecology, describes a universal scaling relationship between variance sigma p and mean mu p with sigma p=e alpha mu p beta . This study investigates the validity of this law in surface metrology as a new method of uncertainty estimation by analyzing areal surface parameters from ISO 25178-2. The amplitude, spatial, slope, curvature, fractal and directional families of parameters are especially analyzed. These parameters are calculated on 3600 topographies measured by interferometry at the same location of a #120 ground TA6V surface for 6 days. By using a two-level bootstrap combined with multi-scale filtering (band-pass, high-pass, and low-pass), we systematically tested the robustness of the law. Results show that intercepts alpha evolve consistently with filtering strategies, slopes beta remain statistically indistinguishable from unity at the 95% confidence level, and goodness-of-fit coefficients (R2) confirm the validity of the power-law across scales. Among parameter families, spatial descriptors exhibit the highest statistical stability, while amplitude and directional parameters provide complementary information: amplitude parameters exhibit moderate dispersion while directional parameters reflect anisotropic surface complexity. These findings demonstrate that Taylor's law reliably governs surface texture parameter variability and can be used to establish predictive uncertainty laws from a single measurement. This opens perspectives for both industrial applications (process monitoring, quality control, surface engineering, etc) and academic one (non-invasive diagnostics, metrology, historical materials, etc).
Osteoarthritis (OA) is a degenerative skeletal condition marked by the loss of articular cartilage and changes to subchondral bone homeostasis. Treatments for OA beyond full joint replacement are lacking primarily due to gaps in molecular knowledge of the biological drivers of disease. Mass Spectrometry Imaging (MSI) enables molecular spatial mapping of the proteomic landscape of tissues. Histologic sections of human tibial plateaus from knees of human OA patients and cadaveric controls were treated with collagenase III to target extracellular matrix (ECM) proteins prior to MS Imaging of bone and cartilage proteins. Spatial MS imaging of the knee identified distinct areas of joint damage to the subchondral bone underneath areas of lost cartilage. This damaged bone signature extended underneath remaining cartilage in OA joints, indicating subchondral bone remodeling could occur before full thickness cartilage loss in OA. Specific ECM peptide markers from OA-affected medial tibial plateaus were compared to their healthier lateral halves from the same patient, as well as to healthy, age-matched cadaveric knees. Overall, 31 peptide candidates from ECM proteins, including Collagen alpha-1(I), Collagen alpha-1(III), and surprisingly, Collagen alpha-1(VI) and Collagen alpha-3(VI), exhibited significantly elevated abundance in diseased tissues. Additionally, highly specific hydroxyproline-containing collagen peptides, mainly from collagen type I, dominated OA subchondral bone directly under regions of lost cartilage but not areas where cartilage remained intact. A separate analysis of synovial fluid from a second cohort of OA patients found similar regulation of collagens and ECM proteins via LC-MS/MS demonstrating that markers of subchondral bone remodeling discovered by MALDI-MS may be detectable as biomarkers in biofluid samples. The identification of specific protein markers for subchondral bone remodeling in OA advances our molecular understanding of disease progression in OA and provides potential new biomarkers for OA detection and disease grading.
Dissolution dynamic nuclear polarization (dDNP) is a hyperpolarization method providing an orders-of-magnitude sensitivity boost for liquid-state nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) experiments. We recently introduced a hyperpolarization strategy based on DNP at 1 T and 77 K (instead of 7 T and 1.2 K) and demonstrated two-orders-of-magnitude signal enhancements with a compact and affordable benchtop instrumentation, designed to enable repeated hyperpolarization cycles for multiscan NMR experiments. However, as in conventional dDNP, the required presence of paramagnetic polarizing agents for DNP is a major roadblock to melting the sample without dilution. The introduction of hyperpolarizing porous polymer (HYPOP) matrices achieved the paradoxical goal of generating fast polarization while preserving long relaxation times within the matrix. In this study, we evaluate DNP with HYPOP under benchtop conditions, and we demonstrate how paramagnetic relaxation effects can be minimized before and after dilution-free melting. We report 1H signal enhancement factors exceeding 45 and 13C polarization lifetimes over 50 s at 77 K and 18 s at 298 K, while the sample remains impregnated in the matrix. This represents a key milestone toward nondestructive melt DNP for replenishable hyperpolarized solution-state NMR.
The NMR interaction tensors of 9 Be and 11 B of hambergite, BeBOOH, were derived from single‐crystal NMR experiments. In the orthorhombic crystal structure of hambergite (which we redetermined by single‐crystal XRD, confirming the results of previous studies), both beryllium and boron atoms occupy Wyckoff position , with atoms pairwise related by inversion symmetry. This leads to four magnetically independent 9 Be and 11 B atoms per site, which are observable in the NMR spectra. Unequivocal assignment of these resonances to atomic positions in the unit cell is generally impossible, as an analysis of the symmetry relations shows. For the hambergite system, this assignment ambiguity could be resolved with the help of DFT calculations using the VASP code, with the resulting eigenvectors compared with the experimental ones. Examination of 9 Be– 1 H dipolar coupling effects, which could be detected in some of the 9 Be spectra, in combination with XRD experiments to confirm the goniometer axis orientation, provided further spatial information and confirmed the assignment. The thus determined numerical values for the quadrupolar coupling constants and isotropic chemical shifts are as follows: for 9 Be[1] kHz and 1.6 ppm, for 9 Be[2] kHz and 1.4 ppm and for 11 B[1] MHz and 18.1 ppm.
Ultraviolet photodissociation (UVPD) of proteins is known to exhibit conformation-dependent fragmentation patterns, but direct structural evidence linking precursor protein and fragment ions has been limited. Here, we apply tandem trapped-ion mobility spectrometry/tandem-mass spectrometry to compare collision cross sections of UVPD fragment ions generated from distinct conformers of ubiquitin. Under the high-pressure (∼4 mbar) and low-photon density (∼10 μJ laser pulse energies) conditions employed here, UVPD produces predominantly [b + 2] and [y - 2] ions at proline residues, consistent with direct bond cleavage from the electronically excited state. Our data show that these ions can retain a clear structural relationship to the precursor conformation: UVPD of compact, native-like ubiquitin yields fragments with collision cross sections ∼20% smaller than the corresponding ions produced from extended precursors or by collision-induced dissociation. Further, these compact UVPD fragments are kinetically trapped in metastable conformations, with substantial barriers preventing relaxation toward energetically favored gas-phase structures. We attribute this behavior to limited vibrational energy deposition per absorbed 213 nm photon combined with rapid collisional cooling, which suppress cumulative thermal activation and disfavor statistical fragmentation pathways, leaving direct excited-state dissociation as the dominant observable process. Together with prior UVPD studies on holo-myoglobin, our results suggest that UVPD fragments can retain aspects of their precursor tertiary structure.
