1,796 research outputs found
Technological systems and momentum change: American electric utilities, restructuring, and distributed generation
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Wind turbines and invisible technology: unarticulated reasons for local opposition to wind energy
Local opposition to wind turbines stems from concerns about environmental and economic damage, as well as conflicts between rural and urban residents. This essay goes beyond these considerations to explore the often-unarticulated explanations for animosity toward this energy technology. Originally, it posits that opposition to visually obvious turbines arises from the successful history of an electric utility system that made its product largely invisible in its manufacture and physical manifestation. The existence of conspicuous turbines, however, reminds observers that power generation requires difficult choices in a technology-based society. The system’s previous achievement in hiding infrastructural elements, in other words, sometimes works ironically to spur objections to wind turbines. Receiving little historical study, the concealed features of a system’s infrastructure often influence assessments of technologies. By revealing the previously invisible, this essay, which draws on research in history, landscape architecture, geography, and psychology, therefore provides insights for social scientists and policymakers
Weekly nab-Paclitaxel in Combination With Carboplatin as First-Line Therapy in Patients With Advanced Non–Small-Cell Lung Cancer: Analysis of Safety and Efficacy in Patients With Diabetes
AbstractPurposeTo examine outcomes in a phase 3 trial of nab-paclitaxel plus carboplatin (nab-P/C) versus solvent-based paclitaxel plus carboplatin (sb-P/C) in a subset of patients with advanced non–small-cell lung cancer (NSCLC) and diabetes.Patients and MethodsPatients with stage IIIB/IV NSCLC received nab-P 100 mg/m2 on days 1, 8, and 15 or sb-P 200 mg/m2 on day 1, both with C at an area under the curve of 6 mg·min/mL on day 1 every 3 weeks. Overall response rate (ORR) and progression-free survival (PFS) were determined by blinded, independent, centralized review. P values were based on chi-square test for ORR and log-rank test for overall survival (OS) and PFS.ResultsOf the 1052 randomized patients in the phase 3 trial, 61 had diabetes according to prespecified terms (nab-P/C, 31; sb-P/C, 30). ORR for nab-P/C versus sb-P/C in this subset was 52% versus 27% (relative risk ratio, 1.935; P = .046), median PFS was 10.9 versus 4.9 months (hazard ratio, 0.420; P = .016), and median OS was 17.5 versus 11.1 months (hazard ratio, 0.550; P = .057). Treatment differences in PFS remained significant (P ≤ .036) after adjusting for histology, region, stage, race, and age and also remained significant in OS for histology (P = .039). Patients with diabetes experienced lower rates of grade 3 or higher neutropenia and peripheral neuropathy and higher rates of thrombocytopenia and anemia with nab-P/C versus sb-P/C.Conclusionnab-P/C demonstrated improved efficacy and manageable tolerability in patients with advanced NSCLC and diabetes
Magnon-Paramagnon Effective Theory of Itinerant Ferromagnets
The present work is devoted to the derivation of an effective
magnon-paramagnon theory starting from a microscopic lattice model of
ferromagnetic metals. For some values of the microscopic parameters it
reproduces the Heisenberg theory of localized spins. For small magnetization
the effective model describes the physics of weak ferromagnets in accordance
with the experimental results. It is written in a way which keeps O(3) symmetry
manifest,and describes both the order and disordered phases of the system.
Analytical expression for the Curie temperature,which takes the magnon
fluctuations into account exactly, is obtained. For weak ferromagnets is
well below the Stoner's critical temperature and the critical temperature
obtained within Moriya's theory.Comment: 14 pages, changed content,new result
Non equilibrium effects in fragmentation
We study, using molecular dynamics techniques, how boundary conditions affect
the process of fragmentation of finite, highly excited, Lennard-Jones systems.
We analyze the behavior of the caloric curves (CC), the associated thermal
response functions (TRF) and cluster mass distributions for constrained and
unconstrained hot drops. It is shown that the resulting CC's for the
constrained case differ from the one in the unconstrained case, mainly in the
presence of a ``vapor branch''. This branch is absent in the free expanding
case even at high energies . This effect is traced to the role played by the
collective expansion motion. On the other hand, we found that the recently
proposed characteristic features of a first order phase transition taking place
in a finite isolated system, i.e. abnormally large kinetic energy fluctuations
and a negative branch in the TRF, are present for the constrained (dilute) as
well the unconstrained case. The microscopic origin of this behavior is also
analyzed.Comment: 21 pages, 11 figure
Continuous symmetry of C60 fullerene and its derivatives
Conventionally, the Ih symmetry of fullerene C60 is accepted which is
supported by numerous calculations. However, this conclusion results from the
consideration of the molecule electron system, of its odd electrons in
particular, in a close-shell approximation without taking the electron spin
into account. Passing to the open-shell approximation has lead to both the
energy and the symmetry lowering up to Ci. Seemingly contradicting to a
high-symmetry pattern of experimental recording, particularly concerning the
molecule electronic spectra, the finding is considered in the current paper
from the continuous symmetry viewpoint. Exploiting both continuous symmetry
measure and continuous symmetry content, was shown that formal Ci symmetry of
the molecule is by 99.99% Ih. A similar continuous symmetry analysis of the
fullerene monoderivatives gives a reasonable explanation of a large variety of
their optical spectra patterns within the framework of the same C1 formal
symmetry exhibiting a strong stability of the C60 skeleton.Comment: 11 pages. 5 figures. 6 table
Spin-Wave Theory of the Spiral Phase of the t-J Model
A graded H.P,realization of the SU(2|1) algebra is proposed.A spin-wave
theory with a condition that the sublattice magnetization is zero is
discussed.The long-range spiral phase is investigated.The spin-spin correlator
is calculated.Comment: 17 page
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