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There is tremendous interest in employing collective excitations of the lattice, spin, charge, and orbitals to tune strongly correlated electronic phenomena. We report such an effect in a ruthenate, Ca 3 Ru 2 O 7 , where two phonons with strong electron-phonon coupling modulate the electronic pseudogap as well as mediate charge and spin density wave fluctuations. Combining temperature-dependent Raman spectroscopy with density functional theory reveals two phonons, B 2 P and B 2 M , that are strongly coupled to electrons and whose scattering intensities respectively dominate in the pseudogap versus the metallic phases. The B 2 P squeezes the octahedra along the out of plane c -axis, while the B 2 M elongates it, thus modulating the Ru 4d orbital splitting and the bandwidth of the in-plane electron hopping; Thus, B 2 P opens the pseudogap, while B 2 M closes it. Moreover, the B 2 phonons mediate incoherent charge and spin density wave fluctuations, as evidenced by changes in the background electronic Raman scattering that exhibit unique symmetry signatures. The polar order breaks inversion symmetry, enabling infrared activity of these phonons, paving the way for coherent light-driven control of electronic transport. Electronic bandwidth modulation by static pressure has been explored in several material families. Wang et al. use temperature-dependent Raman spectroscopy and density functional theory to reveal phonon-driven modulation of electronic pseudogap and density wave fluctuations in a ruthenate Ca 3 Ru 2 O 7 .

Unraveling collective modes arising from coupled degrees of freedom is crucial for understanding complex interactions in solids and developing new functionalities. Unique collective behaviors emerge when two degrees of freedom, ordered on distinct length scales, interact. Polar skyrmions, three-dimensional electric polarization textures in ferroelectric superlattices, disrupt the lattice continuity at the nanometer scale with nontrivial topology, leading to previously unexplored collective modes. Here, using terahertz-field excitation and femtosecond x-ray diffraction, we discover subterahertz collective modes, dubbed “skyrons”, which appear as swirling patterns of atomic displacements functioning as atomic-scale gearsets. The key to activating skyrons is the use of the THz field that couples primarily to skyrmion domain walls. Momentum-resolved time-domain measurements of diffuse scattering reveal an avoided crossing in the dispersion relation of skyrons. Atomistic simulations and dynamical phase-field modeling provide microscopic insights into the three-dimensional crystallographic and polarization dynamics. The amplitude and dispersion of skyrons are demonstrated to be controlled by sample temperature and electric-field bias. The discovery of skyrons and their coupling with terahertz fields opens avenues for ultrafast control of topological polar structures. Polar skyrmions are nanoscale topological structures of electric polarizations. Their collective modes, dubbed as “skyrons”, are discovered by the terahertz-field-excitation, femtosecond x-ray diffraction measurements and advanced modeling.

The Hubbard model is believed to capture the essential physics of cuprate superconductors. However, recent theoretical studies suggest that it fails to reproduce a robust and homogeneous superconducting ground state. Here, using resonant inelastic x-ray scattering and density matrix renormalization group calculations, we show that magnetic excitations in the prototypical cuprate ladder Sr 14 Cu 24 O 41 are inconsistent with those of a simple Hubbard model. The magnetic response of hole carriers, contributing to an emergent branch of spin-flip excitations, is strongly suppressed. This effect is the consequence of strong d -wavelike pairing, enhanced by nearly an order of magnitude through a large nearest-neighbor attractive interaction and persisting up to at least 260 K. The close connection between the physics of cuprate ladders and that of the two-dimensional compounds suggests that such an enhanced hole pairing may be a universal feature of superconducting cuprates.

Ultrafast stimuli can stabilize metastable states of matter inaccessible by equilibrium means. Establishing the spatiotemporal link between ultrafast excitation and metastability is crucial to understand these phenomena. Here we utilize single-shot optical pump–X-ray probe measurements to capture snapshots of the emergence of a persistent polar vortex supercrystal in a heterostructure that hosts a fine balance between built-in electrostatic and elastic frustrations by design. By perturbing this balance with photoinduced charges, an initially heterogeneous mixture of polar phase disorders within a few picoseconds, leading to a state composed of disordered ferroelectric and suppressed vortex orders. On the picosecond–nanosecond timescales, transient labyrinthine fluctuations develop, accompanied by the recovery of the vortex order. On longer timescales, these fluctuations are progressively quenched by dynamical strain modulations, which drive the collective emergence of a single vortex supercrystal phase. Our results, corroborated by dynamical phase-field modelling, reveal non-equilibrium pathways following the ultrafast excitation of designer systems to persistent metastability. Understanding transformations of non-equilibrium materials is a key open scientific question. Here the pathway by which different polar supertextures undergo dynamical correlations and collectively transform into a metastable supercrystal state is revealed experimentally and theoretically over seven orders of magnitude timescale.

The Hubbard model is believed to capture the essential physics of cuprate superconductors. However, recent theoretical studies suggest that it fails to reproduce a robust and homogeneous superconducting ground state. Here, using resonant inelastic x-ray scattering and density matrix renormalization group calculations, we show that magnetic excitations in the prototypical cuprate ladder Sr14⁢Cu24⁢O41 are inconsistent with those of a simple Hubbard model. The magnetic response of hole carriers, contributing to an emergent branch of spin-flip excitations, is strongly suppressed. This effect is the consequence of strong 𝑑-wavelike pairing, enhanced by nearly an order of magnitude through a large nearest-neighbor attractive interaction and persisting up to at least 260 K. The close connection between the physics of cuprate ladders and that of the two-dimensional compounds suggests that such an enhanced hole pairing may be a universal feature of superconducting cuprates.

Introduction Melioidosis caused by Burkholderia pseudomallei, often referred to as a great mimicker or escapist, evades not only the immune system, but also all manual identification methods in an under-equipped clinical microbiology laboratory due to its tedious identification process. This is a case report of disseminated melioidosis with septic arthritis, misdiagnosed both clinicoradiologically and microbiologically as disseminated tuberculosis or other bacterial infection. Case history A middle-aged Asian diabetic male presented with high-grade fever and breathlessness for 4 days along with left knee and ankle swelling for 40 days. Previous hospitalization records revealed growth of pan-sensitive Acinetobacter spp. from ankle and a chest X-ray suspecting tuberculosis for which antibiotic and antitubercular regimen were initiated. After admission, repeated blood cultures and pus culture (ankle and knee joint) confirmed Burkholderia pseudomallei with VITEK-II automated identification system. Recommended therapy was initiated according to revised Darwin’s guideline, leading to gradual cure of the patient. Conclusion Misidentification leads to inadequate treatment, as melioidosis medication is different from other bacterial infections. Here initiation of meropenem- and cotrimoxazole-intensive therapy for 4 weeks, and 6-month eradication phase with cotrimoxazole, resulted in gradual recovery of the patient. It took around 21 days of intensive antibiotic therapy to get bacteriological clearance from blood, which signifies the tenacious nature of this infection.

This article illustrates the failure analysis of the bend pulley shaft, which prematurely failed after a service life of 4 months compared to an expected service life of 10 years. Failure analysis comprised the collection of background information, on-site observations, visual observations, fractography using scanning electron microscopy, chemical analysis, macro-etching, microstructural investigation using optical microscopy and SEM coupled with hardness, tensile tests, and Charpy impact toughness measurement. The clearly visible beach marks on the fracture surface confirmed the nature of the failure to be fatigue. Fractography revealed the presence of striations, which are microscopic signatures of fatigue failure. Despite acceptable strength and elongation, the failed shaft showed lower impact toughness than the desired value. Microstructural analysis revealed an as-cast structure, indicating an improper forging ratio to break the as-cast structure. Further, severe non-metallic inclusions were observed, which are known to reduce the fatigue life of rotating components. Recommendations are provided to improve the metallurgical aspects of the shaft to prevent the recurrence of similar failures in the future.

In hot rolling mills, failure of work rolls is a major concern as it adversely affects mill operations and impacts production. These rolls fracture or spall due to many different reasons. Analysis of failed or spalled roll materials and actual rolling conditions in service are therefore necessary to understand the roll failure mechanism. The hot strip mill referred here consists of two stands in a roughing mill and seven stands in a finishing mill. HSS cast iron rolls are used in the primary strands of finishing mill for the rolling of cast slabs into HR sheets. This present case study describes the spalling of one of the finishing stand non-forged work rolls, and the analysis carried out using destructive as well as non-destructive testing techniques. The spalled roll showed fatigue arrest marks in a smooth continuous path along the circumferential direction. Characteristic features of the fracture surface were like those of surface-initiated spalling which is known as ribbon fatigue spalling. The fracture or spalled region was analysed using ultrasonic tests to identify the origin of the crack. A sample was also collected from the crack origination location where multiple cracks/fire cracks were observed. A detail micro-structural as well as SEM/EDS characterization of the fire cracks was done to understand the mechanism of spalling. The analysis revealed that fire cracks originated from the development of localized thermal stresses on the roll surface. These cracks resulted the roll spalling in operation.

Background Odisha is a state in India endemic to anthrax disease with frequent reports of suspected animal cases. A suspected outbreak of anthrax in humans was reported on 24 October 2021 at Tukum village in Koraput district of Odisha, India after a bullock was found dead and consumed by the locals on 17 October 2021. Methods This extended outbreak investigation was carried out through house‐to‐house active surveillance from 24 October to 2 November 2021 in the Koraput district. Eschar skin swabs from wounds were collected and processed at District Public Health Laboratory, Koraput, and analyzed in Indian Council of Medical Research‐Regional Medical Research Centre, Bhubaneswar for molecular confirmation. Samples from bone, soil, and dried meat were collected from the contaminated sites and were transported to Animal Diseases Research Institute, Cuttack for confirmation. Results Four suspected cases of human anthrax were identified who had handled and consumed dead bullock meat, among which one human had died later. The attack rate of the persons at risk in the village was calculated to be 1.23%. However, no Bacillus anthracis were identified in human swab samples when tested in real‐time polymerase chain reaction. Samples collected from contaminated sites were confirmed to have anthrax bacilli. Conclusion Investigation revealed that a suspected anthrax cluster outbreak was due to butchering/de‐skinning and consumption of the anthrax‐infected dead animal. The presence of bacilli in human samples could not be confirmed due to the intake of antibiotics before the collection of sample. This finding highlighted the importance of sample collection at a suitable time and a possible need for one health approach for better coordination among the different responsible departments. A suspected human anthrax outbreak was notified in the Koraput district of Odisha, India in October 2021. Routine surveillance, timely vaccination of livestock, and proper disposal of livestock carcasses are the most efficient ways of preventing and controlling anthrax infection in domestic herds.