61 research outputs found
Design of reinforced concrete water tower and tank
Theoretically the most economical dimension for a flat bottomed cylindrical tank would be such that the height of the tank is equal to the diameter, but such a tank does not look as well as one which has the height a little greater than the diameter and as the cost will be affected but little by making the height a few feet greater than the diameter, the most economical design will not be strictly carried out in this particular --Data, page 1
Effects of Disorder on the Pressure-Induced Mott Transition in -BEDT-TTF)Cu[N(CN)]Cl
We present a study of the influence of disorder on the Mott metal-insulator
transition for the organic charge-transfer salt
-(BEDT-TTF)Cu[N(CN)]Cl. To this end, disorder was introduced
into the system in a controlled way by exposing the single crystals to x-ray
irradiation. The crystals were then fine-tuned across the Mott transition by
the application of continuously controllable He-gas pressure at low
temperatures. Measurements of the thermal expansion and resistance show that
the first-order character of the Mott transition prevails for low irradiation
doses achieved by irradiation times up to 100 h. For these crystals with a
moderate degree of disorder, we find a first-order transition line which ends
in a second-order critical endpoint, akin to the pristine crystals. Compared to
the latter, however, we observe a significant reduction of both, the critical
pressure and the critical temperature . This result is consistent
with the theoretically-predicted formation of a soft Coulomb gap in the
presence of strong correlations and small disorder. Furthermore, we
demonstrate, similar to the observation for the pristine sample, that the Mott
transition after 50 h of irradiation is accompanied by sizable lattice effects,
the critical behavior of which can be well described by mean-field theory. Our
results demonstrate that the character of the Mott transition remains
essentially unchanged at a low disorder level. However, after an irradiation
time of 150 h, no clear signatures of a discontinuous metal-insulator
transition could be revealed anymore. These results suggest that, above a
certain disorder level, the metal-insulator transition becomes a smeared
first-order transition with some residual hysteresis.Comment: 20 pages, 7 figures, appeared in the Special Issue "Advances in
Organic Conductors and Superconductors" of Crystal
Spin-orbit physics of j=1/2 Mott insulators on the triangular lattice
The physics of spin-orbital entanglement in effective j = 1/2 Mott insulators, which have been experimentally observed for various 5d transition metal oxides, has sparked an interest in Heisenberg-Kitaev (HK) models thought to capture their essential microscopic interactions. Here we argue that the recently synthesized Ba3IrTi2O9 is a prime candidate for a microscopic realization of the triangular HK model -a conceptually interesting model for its interplay of geometric and exchange frustration. We establish that an infinitesimal Kitaev exchange destabilizes the 120 • order of the quantum Heisenberg model. This results in the formation of an extended Z2-vortex crystal phase in the parameter regime most likely relevant to the real material, which can be experimentally identified with spherical neutron polarimetry. Moreover, using a combination of analytical and numerical techniques we map out the entire phase diagram of the model, which further includes various ordered phases as well as an extended nematic phase around the antiferromagnetic Kitaev point
A phase I study of dexosome immunotherapy in patients with advanced non-small cell lung cancer
BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1–2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52–665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effector
Elastocaloric determination of the phase diagram of SrRuO
One of the main developments in unconventional superconductivity in the past two decades has been the discovery that most unconventional superconductors form phase diagrams that also contain other strongly correlated states. Many systems of interest are therefore close to more than one instability, and tuning between the resultant ordered phases is the subject of intense research1. In recent years, uniaxial pressure applied using piezoelectric-based devices has been shown to be a particularly versatile new method of tuning, leading to experiments that have advanced our understanding of the fascinating unconventional superconductor SrRuO. Here we map out its phase diagram using high-precision measurements of the elastocaloric effect in what we believe to be the first such study including both the normal and the superconducting states. We observe a strong entropy quench on entering the superconducting state, in excellent agreement with a model calculation for pairing at the Van Hove point, and obtain a quantitative estimate of the entropy change associated with entry to a magnetic state that is observed in proximity to the superconductivity. The phase diagram is intriguing both for its similarity to those seen in other families of unconventional superconductors and for extra features unique, so far, to SrRuO
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Flavin-Containing Monooxygenase S-Oxygenation of a Series of Thioureas and Thiones
Mammalian flavin-containing monooxygenase (FMO) is active towards many drugs with a heteroatom having the properties of a soft nucleophile. Thiocarbamides and thiones are S-oxygenated to the sulfenic acid which can either react with glutathione and initiate a redox-cycle or be oxygenated a second time to the unstable sulfinic acid. In this study, we utilized LC-MS/MS to demonstrate that the oxygenation by hFMO of the thioureas under test terminated at the sulfenic acid. With thiones, hFMO catalyzed the second reaction and the sulfinic acid rapidly lost sulfite to form the corresponding imidazole. Thioureas are often pulmonary toxicants in mammals and, as previously reported by our laboratory, are excellent substrates for hFMO2. This isoform is expressed at high levels in the lung of most mammals, including non-human primates. Genotyping to date indicates that individuals of African (up to 49%) or Hispanic (2-7%) ancestry have at least one allele for functional hFMO2 in lung, but not Caucasians nor Asians. In this study the major metabolite formed by hFMO2 with thioureas from Allergan, Inc. was the sulfenic acid that reacted with glutathione. The majority of thiones were poor substrates for hFMO3, the major form in adult human liver. However, hFMO1, the major isoform expressed in infant and neonatal liver and adult kidney and intestine, readily S-oxygenated thiones under test, with K[subscript m]s ranging from 7-160 μM and turnover numbers of 30-40 min⁻¹. The product formed was identified by LC-MS/MS as the imidazole. The activities of the mouse and human FMO1 and FMO3 orthologs were in good agreement with the exception of some thiones for which activity was much greater with hFMO1 than mFMO1.Keywords: Flavin-containing monooxygenase, Drug development, Thiones, Thiourea
Synthesis of Strained γ-Lactams by Palladium(0)-Catalyzed C(sp3)−H Alkenylation and Application to Alkaloid Synthesis
A variety of strained α-alkylidene-γ-lactams were synthesized by palladium(0)-catalyzed intramolecular C(sp3)−H alkenylation from easily accessible acyclic and monocyclic bromoalkene precursors. These lactams are valuable intermediates for accessing various classes of mono- and bicylic alkaloids containing a pyrrolidine ring, as illustrated with the synthesis of an advanced model of the marine natural product plakoridine A and of the indolizidine alkaloid δ-coniceine
The effects of neoadjuvant chemoradiotherapy and an in-hospital exercise training programme on physical fitness and quality of life in locally advanced rectal cancer patients (The EMPOWER Trial): Study protocol for a randomised controlled trial
Background: The standard treatment pathway for locally advanced rectal cancer is neoadjuvant chemoradiotherapy (CRT) followed by surgery. Neoadjuvant CRT has been shown to decrease physical fitness, and this decrease is associated with increased post-operative morbidity. Exercise training can stimulate skeletal muscle adaptations such as increased mitochondrial content and improved oxygen uptake capacity, both of which are contributors to physical fitness. The aims of the EMPOWER trial are to assess the effects of neoadjuvant CRT and an in-hospital exercise training programme on physical fitness, health-related quality of life (HRQoL), and physical activity levels, as well as post-operative morbidity and cancer staging. Methods/Design: The EMPOWER Trial is a randomised controlled trial with a planned recruitment of 46 patients with locally advanced rectal cancer and who are undergoing neoadjuvant CRT and surgery. Following completion of the neoadjuvant CRT (week 0) prior to surgery, patients are randomised to an in-hospital exercise training programme (aerobic interval training for 6 to 9 weeks) or a usual care control group (usual care and no formal exercise training). The primary endpoint is oxygen uptake at lactate threshold ( V · o 2 at δ L ) measured using cardiopulmonary exercise testing assessed over several time points throughout the study. Secondary endpoints include HRQoL, assessed using semi-structured interviews and questionnaires, and physical activity levels assessed using activity monitors. Exploratory endpoints include post-operative morbidity, assessed using the Post-Operative Morbidity Survey (POMS), and cancer staging, assessed by using magnetic resonance tumour regression grading. Discussion: The EMPOWER trial is the first randomised controlled trial comparing an in-hospital exercise training group with a usual care control group in patients with locally advanced rectal cancer. This trial will allow us to determine whether exercise training following neoadjuvant CRT can improve physical fitness and activity levels, as well as other important clinical outcome measures such as HRQoL and post-operative morbidity. These results will aid the design of a large, multi-centre trial to determine whether an increase in physical fitness improves clinically relevant post-operative outcomes
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