29 research outputs found
Magnetoconductance anisotropy of a polymer thin film at the onset of metallicity
Thin films of poly(2,5-bis(3-dodecyl-2-yl)-thieno[3,2-b] thiophene) (C12-PBTTT) polymer under electrolyte gating and doping are investigated as model systems for organic thin films devices approaching the metallic side of a metal-insulator (M-I) transition. For the most doped samples, with an estimated density reaching 8 x 10(20) cm(-3) holes and a conductivity exceeding 1000 S cm(-1), a positive high-field magnetoconductance is found in a limited temperature range window and only when the field is perpendicular to the sample plane. This signature of weak localization, combined with indications of finite zero-temperature conductivity, allows us to identify delocalized metallic-like transport in these thin films, even though the conductivity decreases when cooling down the samples. (C) 2015 AIP Publishing LLC
Spina bifida-predisposing heterozygous mutations in Planar Cell Polarity genes and Zic2 reduce bone mass in young mice
Fractures are a common comorbidity in children with the neural tube defect (NTD) spina bifida. Mutations in the Wnt/planar cell polarity (PCP) pathway contribute to NTDs in humans and mice, but whether this pathway independently determines bone mass is poorly understood. Here, we first confirmed that core Wnt/PCP components are expressed in osteoblasts and osteoclasts in vitro. In vivo, we performed detailed µCT comparisons of bone structure in tibiae from young male mice heterozygous for NTD-associated mutations versus WT littermates. PCP signalling disruption caused by Vangl2 (Vangl2Lp/+) or Celsr1 (Celsr1Crsh/+) mutations significantly reduced trabecular bone mass and distal tibial cortical thickness. NTD-associated mutations in non-PCP transcription factors were also investigated. Pax3 mutation (Pax3Sp2H/+) had minimal effects on bone mass. Zic2 mutation (Zic2Ku/+) significantly altered the position of the tibia/fibula junction and diminished cortical bone in the proximal tibia. Beyond these genes, we bioinformatically documented the known extent of shared genetic networks between NTDs and bone properties. 46 genes involved in neural tube closure are annotated with bone-related ontologies. These findings document shared genetic networks between spina bifida risk and bone structure, including PCP components and Zic2. Genetic variants which predispose to spina bifida may therefore independently diminish bone mass
Vapour phase isopropylation of biphenyl over modified molecular sieve catalysts
71-74The vapour
phase isopropylation of biphenyl was
carried over modified Y, SAPO and MCM-41 molecular sieves. The
conversions of biphenyl were in the range of 31-77% and the selectivities
of dialkylated biphenyl were 35-53%. The
effect of various reaction parameters like reaction
temperature, weight hourly space velocity, molar ratio were studied. The
dialkylated products were more over MCM-41
catalysts and the ratio of
∑monoalkylated/∑dialkylated in the products varied
with the catalyst and time on stream
On the linkage between mesospheric gravity waves and occurrence of equatorial plasma bubble observed during the low solar activity
264-270In this paper, the linkage between the low-latitude
mesospheric gravity waves and the equatorial plasma bubble (EPB) have been
investigated using simultaneously Rayleigh lidar and VHF radar observations
from Gadanki (13.5oN, 79.2oE) and ionosonde observations
from Tirunelveli (8.7oN, 77.8oE) made between 2007 and
2009 when solar activity was undergoing a deep minima. The two sets of
observations have been analysed, each comprising of one case having EPB and
another without EPB observed on two nearby nights. Observations show that the
occurrences of plume structures in the radar observations are found to have a
close link with the amplitudes of the short period gravity waves in the
mesospheric temperature. It is argued that such waves have an important role in
seeding the Rayleigh-Taylor (RT) instability manifesting EPB
Synthesis of sulphur containing compounds over molecular sieve catalysts
425-426Cyclization of aliphatic butane 1,4-diol in
presence of hydrogen sulphide gas was carried out in the vapour phase. The catalysts
used for this reaction are modified and unmodified ZSM-5 and HY molecular sieves.
The effect of variation of catalyst and reaction temperature are studied for this
reaction. A probable reaction mechanism for the formation of butane dithiol, which
is used as protecting agent in the organic synthesis was proposed
The spatial distribution of molecular Hydrogen in the lunar atmosphere—new results
The measurements carried out by Chandra׳s Altitudinal Composition Explorer (CHACE) onboard the Moon Impact Probe (MIP) of Chandrayaan I mission is used to obtain information on the 2-D distribution of the lunar atmospheric H2 by a novel approach that makes use of the basic fact that the Moon has a Surface Boundary Exosphere (SBE).These are the ‘first’ daytime in situ measurements of lunar H2 covering the 20°S to 88°S latitude region centered ~14°E longitude. A critical examination of the observed spatial features of the surface number density of H2 vis-à-vis the surface topography delineated from the Lunar Laser Ranging Instrument (LLRI) in the main orbiter Chandrayaan-I, indicates that that lunar surface process may be important in introducing small scale variations in the H2 number density. Another constituent which exhibited spatial variation in the observed partial pressure is 40Ar and it was hypothesized that it is indicative of the spatial heterogeneity in the radiogenic activity of the Lunar interior (Sridharan et al., 2013a). The absolute number density at the surface and also the latitude/altitude variation of the densities that are reported for the first time, highlight the complexities of the sunlit lunar atmosphere
Combined Bottom-Up and Top-Down Approach for Highly Ordered One-Dimensional Composite Nanostructures for Spin Insulatronics
Engineering magnetic proximity effects-based devices requires developing efficient magnetic insulators. In particular, insulators, where magnetic phases show dramatic changes in texture on the nanometric level, could allow us to tune the proximity-induced exchange splitting at such distances. In this paper, we report the fabrication and characterization of highly ordered two-dimensional arrays of LaFeO3 (LFO)-CoFe2O4 (CFO) biphasic magnetic nanowires, grown on silicon substrates using a unique combination of bottom-up and top-down synthesis approaches. The regularity of the patterns was confirmed using atomic force microscopy and scanning electron microscopy techniques, whereas magnetic force microscopy images established the magnetic homogeneity of the patterned nanowires and absence of any magnetic debris between the wires. Transmission electron microscopy shows a close spatial correlation between the LFO and CFO phases, indicating strong grain-to-grain interfacial coupling, intrinsically different from the usual core-shell structures. Magnetic hysteresis loops reveal the ferrimagnetic nature of the composites up to room temperature and the presence of a strong magnetic coupling between the two phases, and electrical transport measurements demonstrate the strong insulating behavior of the LFO-CFO composite, which is found to be governed by Mott-variable range hopping conduction mechanisms. A shift in the Raman modes in the composite sample compared to those of pure CFO suggests the existence of strain-mediated elastic coupling between the two phases in the composite sample. Our work offers ordered composite nanowires with strong interfacial coupling between the two phases that can be directly integrated for developing multiphase spin insulatronic devices and emergent magnetic interfaces
Spin Transition in Arrays of Gold Nanoparticles and Spin Crossover Molecules
Quantum Matter and Optic
Venetoclax combinations delay the time to deterioration of HRQoL in unfit patients with acute myeloid leukemia
Phase 3 trials Viale-A and Viale-C evaluated health-related quality of life (HRQoL) in patients with AML unfit for intensive chemotherapy who received venetoclax (VEN) + (AZA) (Viale-A) or low-dose cytarabine (LDAC) (Viale-C) or placebo (PBO) + AZA or LDAC. Patient-reported outcomes included: EORTC QLQ-C30 global health status (GHS/QoL) and physical functioning (PF), PROMIS Cancer Fatigue Short Form 7a (Fatigue), and EQ-5D-5L health status visual analog scale (HS-VAS). Time to deterioration (TTD), defined as worsening from baseline in meaningful change thresholds (MCT) of ≥10, 5, or 7 points for GHS/QoL or PF, fatigue, and HS-VAS, respectively, was assessed; differences between groups were analyzed using Kaplan-Meier and unadjusted log-rank analyses. VEN + AZA vs PBO + AZA patients had longer TTD in GHS/QoL (P = 0.066) and fatigue (P = 0.189), and significantly longer TTD in PF (P = 0.028) and HS-VAS (P < 0.001). VEN + LDAC vs PBO + LDAC patients had significantly longer TTD in GHS/QoL (P = 0.011), PF (P = 0.020), and fatigue (P = 0.004), and a trend in HS-VAS (P = 0.057). Approximately 43%, 35%, 32%, and 18% of patients treated with VEN + AZA, AZA + PBO, VEN + LDAC, or LDAC + PBO, respectively, saw improvements >MCT in GHS/QoL. Overall, VEN may positively impact HRQoL in patients with AML ineligible for intensive chemotherapy, leading to longer preservation of functioning and overall health status. © 2022, The Author(s)