The quasi-two-dimensional metal Sr2RuO4 is one of the best characterized unconventional superconductors, yet the nature of its superconducting order parameter is still under debate1–3. This ...information is crucial to determine the pairing mechanism of Cooper pairs. Here we use ultrasound velocity to probe the superconducting state of Sr2RuO4. This thermodynamic probe is sensitive to the symmetry of the material, and therefore, it can help in identifying the symmetry of the superconducting order parameter4,5. Indeed, we observe a sharp jump in the shear elastic constant c66 as the temperature is increased across the superconducting transition. This directly implies that the superconducting order parameter is of a two-component nature. On the basis of symmetry arguments and given the other known properties of Sr2RuO4 (refs. 6–8), we discuss which states are compatible with this requirement and propose that the two-component order parameter {dxz; dyz} is the most likely candidate.Ultrasound experiments show that the superconducting order parameter in strontium ruthenate must have two components.
•MoS2 was exfoliated with NMP to fabricate gas sensors.•Exfoliated MoS2-based sensor shows p-type behavior after annealing in air at 150°C.•Exfoliated MoS2-based sensor shows n-type behavior after ...annealing in air at 250°C.•N substitutional doping is proposed as explanation of the sensor p-type behavior.•MoS2 surface oxidation and S vacancies cause the sensor n-type behavior.
We report on the fabrication, the morphological, structural, and chemical characterization, and the study of the electrical response to NO2 and other gases of resistive type gas sensors based on liquid chemically exfoliated (in N-methyl pyrrolidone, NMP) MoS2 flakes annealed in air either at 150°C or at 250°C. The active material has been analyzed by scanning electron microscopy (SEM), and micro Raman and X-ray core level photoemission spectroscopies. SEM shows that MoS2 exfoliated flakes are interconnected between electrodes of the sensing device to form percolation paths. Raman spectroscopy of the flakes before annealing demonstrates that the flakes are constituted by crystalline MoS2, while, annealing at 250°C, does not introduce a detectable bulk contamination in the expected form of MoO3. The sensor obtained by thermal annealing in air at 150°C exhibits a peculiar p-type response under exposure to NO2. In line with core level spectroscopy evidences, this behavior is potentially ascribed to nitrogen substitutional doping of S vacancies in the MoS2 surface (nitrogen atoms being likely provided by the intercalated NMP). Thermal annealing the MoS2 flakes in air at 250°C irreversibly sets an n-type behavior of the gas sensing device, with a NO2 detection limit of 20ppb. This behavior is assigned, in line with core level spectroscopy data, to a significant presence of S vacancies in the MoS2 annealed flakes and to the surface co-existence of MoO3 arising from the partial oxidation of the flakes surface. Both p- and n-type sensors have been demonstrated to be sensitive also to relative humidity. The n-type sensor shows good electrical response under H2 exposure.
Magnetoresistivity ρ(xx) and Hall resistivity ρ(xy) in ultrahigh magnetic fields up to 88 T are measured down to 0.15 K to clarify the multiband electronic structure in high-quality single crystals ...of superconducting FeSe. At low temperatures and high fields we observe quantum oscillations in both resistivity and the Hall effect, confirming the multiband Fermi surface with small volumes. We propose a novel approach to identify from magnetotransport measurements the sign of the charge carriers corresponding to a particular cyclotron orbit in a compensated metal. The observed significant differences in the relative amplitudes of the quantum oscillations between the ρ(xx) and ρ(xy) components, together with the positive sign of the high-field ρ(xy), reveal that the largest pocket should correspond to the hole band. The low-field magnetotransport data in the normal state suggest that, in addition to one hole and one almost compensated electron band, the orthorhombic phase of FeSe exhibits an additional tiny electron pocket with a high mobility.
The allure of the archives entails a roaming voyage through the words of others, and a search for a language that can rescue their pertinence. Arlette Farge At The University Of Pennsylvania's Kislak ...Center for Special Collections, with the material contents of PennSound spread out in seven boxes before me, I am uncertain where or even how to begin. ...they admit, they aren't exactly certain what "processing" this collection should mean. Jonathan Sterne expands on Hall's precedent to convey a sense of cultural connection through both meaning and, importantly, practice, thus including the array of media and technological apparati that are an integral part of discursive formations (Sterne, The Audible Past 23-24). Beginning with these questions, amid the Kislak Center's archival boxes and the various recording collections that the digital repository articulates, this essay is a material media and cultural analysis of PennSound's formation and implicit pedagogy.
Endoscopic and histologic remission are important goals in the treatment of ulcerative colitis (UC). We investigated the correlation of the recently developed Paddington International Virtual ...ChromoendoScopy ScOre (PICaSSO) and other established endoscopic scores against multiple histological indices and prospectively assessed outcomes.
In this prospective multicenter international study, inflammatory activity was assessed with high-definition and virtual chromoendoscopy in the rectum and sigmoid using the Mayo Endoscopic Score (MES), UC Endoscopic Index of Severity (UCEIS), and PICaSSO. Targeted biopsies were taken for assessment using Robarts Histological Index (RHI), Nancy Histological index (NHI), ECAP (Extent, Chronicity, Activity, Plus score), Geboes, and Villanacci. Follow-up data were obtained at 6 and 12 months after colonoscopy.
A total of 307 patients were recruited. There was strong correlation between PICaSSO and histology scores, significantly superior to correlation coefficients of MES and UCEIS with histology scores. A PICaSSO score of ≤3 detected histologic remission by RHI (≤3 + absence of neutrophils) with area under the receiver operating characteristic curve (AUROC) 0.90 (95% confidence interval CI 0.86–0.94) and NHI (≤1) AUROC 0.82 (95% CI 0.77–0.87). The interobserver agreement for PICaSSO was 0.88 (95% CI 0.83–0.92). At 6- and 12-months follow-up, PICaSSO score ≤3 predicted better outcomes than PICaSSO >3 (hazard ratio HR 0.19 0.11–0.33 and 0.22 0.13–0.34, respectively),} as well as PICaSSO 4–8 (HR 0.25 0.12–0.53 and 0.22 (0.12–0.39), respectively) and similar to histologic remission.
In this first real-life multicenter study, the PICaSSO score correlated strongly with multiple histological indices. Furthermore, PICaSSO score predicted specified clinical outcomes at 6 and 12 months, similar to histology. Thus, PICaSSO can be a useful endoscopic tool in the therapeutic management of UC.
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Abstract
Superconductivity induced by a magnetic field near metamagnetism is a striking manifestation of magnetically-mediated superconducting pairing. After being observed in itinerant ferromagnets, ...this phenomenon was recently reported in the orthorhombic paramagnet UTe
2
. Here we explore the phase diagram of UTe
2
under two magnetic-field directions: the hard magnetization axis
b
, and a direction titled by ≃25-30° from
b
in the (
b
,
c
) plane. Zero-resistivity measurements confirm that superconductivity is established beyond the metamagnetic field
H
m
in the tilted-field direction. While superconductivity is locked exactly at fields either smaller (for
H
| |
b
), or larger (for
H
tilted by ≃27° from
b
to
c
), than
H
m
, the variations of the Fermi-liquid coefficient in the electrical resistivity and of the residual resistivity are similar for the two field directions. The resemblance of the normal states for the two field directions puts constraints for theoretical models of superconductivity and implies that some subtle ingredients must be in play.
To determine prevalence and risk factors for colonization by multidrug-resistant organisms (MDROs) in long-term care facility (LTCF) residents in Italy. Genotypes of MDRO isolates were investigated.
...A point-prevalence study was conducted at 12 LTCFs located in four Italian cities (2 February to 14 March 2015). Rectal swabs, faeces and nasal/auxiliary swabs were cultured for extended-spectrum β-lactamase (ESBL)- and/or carbapenemase-producing Enterobacteriaceae, Clostridium difficile and methicillin-resistant Staphylococcus aureus (MRSA) respectively. Antimicrobial susceptibility testing, detection of ESBL and/or carbapenemase genes and molecular typing of MDROs were performed. Risk factors for colonization were determined by univariate and multivariate analysis.
A total of 489 LTCF residents aged ≥65 years were enrolled. The prevalence of colonization by ESBL-producing Enterobacteriaceae, MRSA and C. difficile was 57.3% (279/487), 17.2% (84/487) and 5.1% (21/409) respectively. Carriage rate of carbapenemase-producing Enterobacteriaceae was 1% (5/487). Being bedridden was a common independent risk factor for colonization by all MDROs, although risk factors specific for each MDRO were identified. ESBL-producing Escherichia coli carriage was associated with the sequence type (ST) 131-H30 subclone, but other minor STs predominated in individual LTCF or in LTCFs located in the same city, suggesting a role for intrafacility or local transmission. Similarly, MRSA from LTCF residents belonged to the same spa types/ST clones (t008/ST8 and t032/ST22) commonly found in Italian acute-care hospitals, but infrequent spa types were recovered in individual LTCFs. The prevalent C. difficile PCR ribotypes were 356/607 and 018, both common in Italian acute-care hospitals.
MDRO colonization is common among residents in Italian LTCFs.
Background Mucosal healing (MH) is a key treatment target in the management of inflammatory bowel disease (IBD) and is defined in endoscopic terms by the newly published PICaSSO score. Raman ...Spectroscopy (RS) is based on the scattering of inelastic light giving spectra that are highly specific for individual molecules. We aimed to establish spectral changes before and after treatment and whether Raman Spectroscopy is able to accurately differentiate between inflammation and MH. Methods Biopsies were taken for ex vivo RS analysis alongside biopsies for histological analysis from IBD patients undergoing optical diagnosis endoscopic assessment. We compared pre- vs. post-biological treatment in IBD patients and healthy controls and active vs. MH in UC and CD. For spectral analysis, we used supervised self-organising maps for separation and classification. Results A total of 23 patients (14 IBD, 9 HC) were recruited for comparison of pre- vs. post-biologic treatment and 74 IBD patients were included for the assessment of MH in IBD, giving 9700 Raman Spectra. Spectral differences were seen between pre- and post-treatment which were observed comparing MH vs. active inflammation. Reductions in intensity at 1003cm.sup.-1 and 1252cm.sup.-1 when a reduction in inflammation was seen post-treatment and when MH was present. MH was associated with an increase in intensity at 1304cm.sup.-1 . The trained neural network differentiated MH from active inflammation with a sensitivity, specificity, PPV, NPV and accuracy in UC of 96.29% (sd 0.94), 95.03% (sd 1.52), 94.89% (sd 1.59), 96.33 (sd 0.97) and 95.65 (sd 0.99) and 96.19% (sd 1.46), 88% (sd 4.20), 86.60% (sd 5.39), 96.55% (sd 1.32) and 91.6% (sd 2.75) in CD respectively. Conclusion We demonstrated RS can demonstrate biochemical changes following treatment of IBD and accurately differentiates MH from active inflammation in IBD and might be a future tool to personalise therapeutic management in IBD.
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