Transport properties of annealed CdSe nanocrystal solids

Transport properties of artificial solids composed of colloidal CdSe nanocrystals (NCs) are studied from 6 K to 250 K, before and after annealing. Annealing results in greatly enhanced dark and photocurrent in NC solids, while transmission electron microscopy (TEM) micrographs show that the inter-dot separation decreases. The increased current can be attributed to the enhancement of inter-dot tunneling caused by the decreased separation between NCs and by chemical changes in their organic cap. In addition, the absorption spectra of annealed solids are slightly red-shifted and broadened. These red-shifts may result from the change of the dielectric environment around the NCs. Our measurements also indicate that Coulomb interactions between charges on neighboring NCs play an important role in the tunneling current.Comment: 24 pages,4 figures, 1 tabl

Imaging the charge transport in arrays of CdSe nanocrystals

A novel method to image charge is used to measure the diffusion coefficient of electrons in films of CdSe nanocrystals at room temperature. This method makes possible the study of charge transport in films exhibiting high resistances or very small diffusion coefficients.Comment: 4 pages, 4 jpg figure

Zeno’s paradox in decision making

Classical probability theory has been influential in modeling decision processes, despite empirical findings that have been persistently paradoxical from classical perspectives. For such findings, some researchers have been successfully pursuing decision models based on quantum theory. One unique feature of quantum theory is the collapse postulate, which entails that measurements (or in decision making, judgments) reset the state to be consistent with the measured outcome. If there is quantum structure in cognition, then there has to be evidence for the collapse postulate. A striking, a priori prediction, is that opinion change will be slowed down (under idealized conditions frozen) by continuous judgments. In physics, this is the quantum Zeno effect. We demonstrate a quantum Zeno effect in decision making in humans and so provide evidence that advocates the use of quantum principles in decision theory, at least in some cases

Quasilocality of joining/splitting strings from coherent states

Using the coherent state formalism we calculate matrix elements of the one-loop non-planar dilatation operator of ${\cal N}=4$ SYM between operators dual to folded Frolov-Tseytlin strings and observe a curious scaling behavior. We comment on the {\it qualitative} similarity of our matrix elements to the interaction vertex of a string field theory. In addition, we present a solvable toy model for string splitting and joining. The scaling behaviour of the matrix elements suggests that the contribution to the genus one energy shift coming from semi-classical string splitting and joining is small.Comment: 17 pages, 7 figures in 11 file

Presentation of the bk21 (Kacprzak) test as a less traumatic alternative to the Lachman test and Drop Leg test in diagnosing anterior cruciate ligament tear

Objective: despite the fact that anterior cruciate ligament injuries are the most common ligament injuries, the problem of making a quick and accurate diagnosis still exists. in our paper, we hypothesized that a modification of the Lachman test — BK21 (Kacprzak test), in comparison to the Lachman test and Drop Leg test will allow for a significant reduction of pain during the test, and thus for less muscular defense, more relaxation, and more reliable test results, whose sensitivity and specificity will be confirmed by magnetic resonance imaging.Materials and methods: using the patient’s subjective pain rating scale, the Numerical Rating Scale (NRS), we were able to easily assess which way of performing the test was less traumatic for the patient. a physical examination in the form of a comparison of those two visits was performed at the private medical office Orto Med Sport in 203 patients with suspected anterior cruciate ligament tear.Results: the BK21 modification (Kacprzak) test was on average 3 points less painful on the NRS scale than the classic Lachman test and 1 point less painful than the Drop Leg test, while the same principle of operation and analogous endpoints in both tests allow for high sensitivity and specificity of the test.Conclusion: the BK21 test was a less traumatic and painful alternative to the Lachman test

Evaluation of the effectiveness of inveterate Achilles tendon rupture V-Y plasty with immediate subsequent weight-bearing and rehabilitation. Case study

In our paper, we would like to present two cases of treatment of the Achilles tendon ruptures by means of surgical V-Y technique, and implementation of immediate rehabilitation and weight-bearing. V-Y plasty on ruptured tendons was performed. The continuity of the tendon was restored. The sheath of the tendon was stitched together. Dressing was put on; the foot was immobilized in a Walker-type shoe in pes equinus with heel pads and compression underwear. From the first hour after the procedure, the wound area was cooled with a Game Ready device. From the first day after the procedure, both patients were allowed to apply full weight to the limb in the shoe. The crutches were put away as soon as possible. Rehabilitation began right away on the next day; during its course, attempts were made to reduce the use of the shoe to a minimum and to achieve the full range of foot motion as soon as possible. In both patients, the full range of motion was reached approximately 2 weeks after the surgery. The video support for the article is available at: https://youtu.be/bi3xuwOT9v

Demography, trade and state power: a tripartite model of medieval farming/language dispersals in the Ryukyu Islands

Hunter-gatherer occupations of small islands are rare in world prehistory and it is widely accepted that island settlement is facilitated by agriculture. The Ryukyu Islands contradict that understanding on two counts: not only did they have a long history of hunter-gatherer settlement, they also have a very late date for the onset of agriculture, which only reached the archipelago between the 8th and 13th centuries AD. Here, we combine archaeology and linguistics to propose a tripartite model for the spread of agriculture and Ryukyuan languages to the Ryukyu Islands. Employing demographic growth, trade/piracy and the political influence of neighbouring states, this model provides a synthetic yet flexible understanding of farming/language dispersals in the Ryukyus within the complex historical background of medieval East Asia.Introduction Methods Results - Archaeological Approach -- Demographic growth -- Trade/piracy -- State intervention - Linguistic Approach -- Linguistic inferences about the most probable tree structure -- Linguistic inferences about the most probable homeland of Proto-Ryukyuan -- Linguistic inferences about the most probable break-up time of Proto-Kyushu-Ryukyuan -- Inferences about the most probable linguistic outcome of the migration Discussion Conclusion

CO2 budgeting at the regional scale using a Lagrangian experimental strategy and meso-scale modeling

An atmospheric Lagrangian experiment for regional CO2 budgeting with aircraft measurements took place during the CarboEurope Regional Experiment Strategy campaign (CERES) in south-west France, in June 2005. The atmospheric CO2 aircraft measurements taken upstream and downstream of an active and homogeneous pine forest revealed a CO2 depletion in the same air mass, using a Lagrangian strategy. This field experiment was analyzed with a meteorological meso-scale model interactively coupled with a surface scheme, with plant assimilation, ecosystem respiration, anthropogenic CO2 emissions and sea fluxes. First, the model was carefully validated against observations made close to the surface and in the atmospheric boundary layer. Then, the carbon budget was evaluated using the numerous CERES observations, by upscaling the surface fluxes observations, and using the modeling results, in order to estimate the relative contribution of each physical process. A good agreement is found between the two methods which use the same vegetation map: the estimation of the regional CO2 surface flux by the Eulerian meso-scale model budget is close to the budget deduced from the upscaling of the observed surface fluxes, and found a budget between −9.4 and −12.1μmol.m−2.s−1, depending on the size of the considered area. Nevertheless, the associated uncertainties are rather large for the upscaling method and reach 50%. A third method, using Lagrangian observations of CO2 estimates a regional CO2 budget a few different and more scattered, (−16.8μmol.m−2.s−1 for the small sub-domain and −8.6μmol.m−2.s−1 for the larger one). For this budgeting method, we estimate a mean of 31% error, mainly arising from the time of integration between the two measurements of the Lagrangian experiment. The paper describes in details the three methods to assess the regional CO2 budget and the associated error

Cryptic Variation in Morphological Evolution: HSP90 as a Capacitor for Loss of Eyes in Cavefish

In the process of morphological evolution, the extent to which cryptic, preexisting variation provides a substrate for natural selection has been controversial. We provide evidence that heat shock protein 90 (HSP90) phenotypically masks standing eye-size variation in surface populations of the cavefish Astyanax mexicanus. This variation is exposed by HSP90 inhibition and can be selected for, ultimately yielding a reduced-eye phenotype even in the presence of full HSP90 activity. Raising surface fish under conditions found in caves taxes the HSP90 system, unmasking the same phenotypic variation as does direct inhibition of HSP90. These results suggest that cryptic variation played a role in the evolution of eye loss in cavefish and provide the first evidence for HSP90 as a capacitor for morphological evolution in a natural setting