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Σάββατο 9 Ιανουαρίου 2016

The role of neurocranial shape in defining the boundaries of an expanded Homo erectus hypodigm

Publication date: March 2016
Source:Journal of Human Evolution, Volume 92
Author(s): Karen L. Baab
The main goals of this study were to evaluate the distinctiveness of Homo erectus neurocranial shape relative to other closely related species, and assess the likelihood that particular fossils were correctly attributed to H. erectus given how shape variation related to geography, time and brain size. This was accomplished through analyses of several sets of landmarks designed to maximize the fossil sample, including 24 putative H. erectus fossils. The question of taxonomic differentiation was initially assessed for the type specimen (Trinil II) and morphologically similar Sangiran fossils and subsequently for increasingly inclusive definitions of H. erectus. Results indicated that H. erectus fossils from China, Indonesia, Georgia and East Africa shared a neurocranial shape that was distinct from that of other Plio-Pleistocene Homo taxa, a pattern only partially accounted for by brain size. Early Indonesian H. erectus formed a morphological "bridge" between earlier and later populations assigned to H. erectus from Africa and Asia, respectively. These results were combined with discrete characters to create a more complete species definition for H. erectus. There were two notable exceptions to the general pattern of H. erectus uniqueness. The 0.8–1.0 Ma (millions of years ago) Daka calvaria from Ethiopia consistently grouped with mid-Pleistocene Homo, including Bodo and Kabwe, rather than African or Asian H. erectus. In addition, Daka also exhibited several traits derived for mid-Pleistocene Homo, and its scaling pattern mirrored mid-Pleistocene Homo rather than H. erectus. Daka may have belonged to an "advanced" H. erectus population close to the root of Homo heidelbergensis sensu lato (s.l.), or to an early population of H. heidelbergensis s.l.. The 1.5 Ma KNM-ER 42700 specimen from Kenya exhibited a unique calvarial shape distinct from H. erectus despite the exclusion of problematic landmarks from the frontal bone. These unique aspects of shape were not present in two other subadult fossils, KNM-WT 15000 and D2700.



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When things go wrong: Cysticercus longicollis in an adult wild red fox ( Vulpes vulpes )

Abstract

First case of Cysticercus longicollis, larval stage of Taenia crassiceps, was diagnosed in a wild adult male red fox (Vulpes vulpes). The fox was killed by dogs at Nature Park Medvednica and presented to the University of Zagreb Faculty of Veterinary Medicine with history of being unable to run away and having skin lesions on legs that resembled to those of mange. Necropsy revealed whitish fluctuant mass full of cysticercus-like structures, surrounded by fibrous capsule and placed between the leg muscles, and numerous of spherical cysts in the subcutis and in the peritoneal cavity. Cysticerci were identified as C. longicollis based on their size, number and size of the rostellar hooks, mode of proliferation and DNA analysis. To our knowledge, this is the first case of T. crassiceps cysticercosis in a wild carnivore.



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Predictions from high scale mixing unification hypothesis

Abstract

Starting with 'high scale mixing unification' hypothesis, we investigate the renormalization group evolution of mixing parameters and masses for both Dirac and Majorana-type neutrinos. Following this hypothesis, the PMNS mixing parameters are taken to be identical to the CKM ones at a unifying high scale. Then, they are evolved to a low scale using MSSM renormalization group equations. For both types of neutrinos, the renormalization group evolution naturally results in a non-zero and small value of leptonic mixing angle 𝜃 13. One of the important predictions of this analysis is that, in both cases, the mixing angle 𝜃 23 turns out to be non-maximal for most of the parameter range. We also elaborate on the important differences between Dirac and Majorana neutrinos within our framework and how to experimentally distinguish between the two scenarios. Furthermore, for both cases, we also derive constraints on the allowed parameter range for the SUSY breaking and unification scales, for which this hypothesis works. The results can be tested by the present and future experiments.



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Next-to-leading order corrections to the valon model

Abstract

A seminumerical solution to the valon model at next-to-leading order (NLO) in the Laguerre polynomials is presented. We used the valon model to generate the structure of proton with respect to the Laguerre polynomials method. The results are compared with H1 data and other parametrizations.



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Determination of optical constants and nonlinear optical coefficients of Violet 1-doped polyvinyl alcohol thin film

Abstract

The optical properties of Violet 1-doped polyvinyl alcohol (PVA) have been investigated using Wemble and Didomenico (WD) method. The optical constants such as refractive index n, the dispersion energy E d, the oscillation energy E 0, the lattice dielectric constant \(\varepsilon _{\infty } \) , light frequency dielectric constant ε 0 and the ratio of carrier concentration to the effective mass N/m* have been determined using reflection spectra in the wavelength range 300–900 nm. The single- beam Z-scan technique was used to determine the nonlinear optical properties of Violet 1:polyvinylalcohol (PVA) thin film. The experiments were performed using continuous wave (cw) laser with a wavelength of 635 nm. The calculated nonlinear refractive index of the film, n 2 = −2.79×10−7 cm2/W and nonlinear absorption coefficient, β = 6.31×10−3 cm /W. Optical limiting characteristics of the dye-doped polymer film was studied. The result reveals that Violet 1 can be a promising material for optical limiting applications.



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Inelastic magnetic electron scattering form factors of the 26 Mg nucleus

Abstract

Magnetic electron scattering (M3) form factors with core polarization effects, energy levels and B(M3) values to 3+ states of the 26Mg nucleus have been studied using shell model calculations. The universal sd of the Wildenthal interaction, universal sd-shell interaction A, universal sd-shell interaction B, are used for the sd-shell orbits. Core polarization effects according to microscopic theory are taken into account by the excitations of nucleons from the (1s 1/2 1p 3/2 1p 1/2) core and also from valence 1d 5/2 2s 1/2 1d 3/2 orbits into higher shells, with \(4\hslash \omega \) excitation. In form factor calculations, the universal sd-shell interaction B for the sd-shell is used with the Michigan three-range Yakawa effective NN interaction as a residual interaction for the core polarization calculations. The wave functions of the radial single-particle matrix elements have been calculated using harmonic oscillator potentials. The level schemes are compared with the experimental data up to 9.902 MeV. In this study, very good agreements are obtained for all nuclei. Results from M3 form factor calculations with the inclusion of core polarization and new g-factors give good agreement with the experimental data.



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Oscillating two-stream instability of laser wakefield-driven plasma wave

Abstract

The laser wakefield-driven plasma wave in a low-density plasma is seen to be susceptible to the oscillating two-stream instability (OTSI). The plasma wave couples to two short wavelength plasma wave sidebands. The pump plasma wave and sidebands exert a ponderomotive force on the electrons driving a low-frequency quasimode. The electron density perturbation associated with this mode couples with the pump-driven electron oscillatory velocity to produce nonlinear currents driving the sidebands. At large pump amplitude, the instability grows faster than the ion plasma frequency and ions do not play a significant role. The growth rate of the quasimode, at large pump amplitude scales faster than linear. The growth rate is maximum for an optimum wave number of the quasimode and also increases with pump amplitude. Nonlocal effects, however reduce the growth rate by about half.



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A novel effective approach for systems of coupled Schrödinger equation

Abstract

Schrödinger equations arise in modelling various physical and engineering problems. In this paper, we introduce a new homotopy perturbation method (NHPM) to improve the accuracy and computational efficiency of the homotopy perturbation method (HPM). We show that this technique enables one to determine the exact solution of the system of Schrödinger equations. Several illustrative examples are given to demonstrate the effectiveness of this method.



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Pressure–temperature dependence of thermodynamic properties of rutile (TiO 2 ): A first-principles study

Abstract

Ab-initio calculations of thermal properties of rutile (TiO2) have been performed by using the projector augmented-wave (PAW) method within the generalized gradient approximation (GGA). Both pressure- and temperature-dependent thermodynamic properties such as the bulk modulus, thermal expansion, thermal expansion coefficient, heat capacity at constant volume and constant pressure were calculated using two different models based on the quasiharmonic approximation (QHA): the Debye–Slater and Debye–Grüneisen model with Dugdale–MacDonald (DM) approximation. Also, the empirical energy corrections were applied to the results to correct the systematic errors introduced by the functional. It is found that the Debye–Grüneisen model provides more accurate estimates than the Debye-Slater models, especially after empirical energy correction.



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Best Practice in Teaching Male Adolescents and Young Men to Perform Testicular Self-Examinations: A Review

Young men and adolescent males are one of the most medically underserved populations in the United States in several aspects of health care, including sexual health and screening. Recommendations about promoting the testicular self-examination (TSE) vary between professional organizations; however, clinicians who decide to promote the technique must frame their education in developmentally appropriate ways and base their approach on methods proven to work with the target population. The purpose of this literature review is to evaluate interventions published in the peer-reviewed literature to identify which types of methods are effective in teaching TSE to young males (≤ 35 years).

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The Threat of Algocracy: Reality, Resistance and Accommodation

Abstract

One of the most noticeable trends in recent years has been the increasing reliance of public decision-making processes (bureaucratic, legislative and legal) on algorithms, i.e. computer-programmed step-by-step instructions for taking a given set of inputs and producing an output. The question raised by this article is whether the rise of such algorithmic governance creates problems for the moral or political legitimacy of our public decision-making processes. Ignoring common concerns with data protection and privacy, it is argued that algorithmic governance does pose a significant threat to the legitimacy of such processes. Modelling my argument on Estlund's threat of epistocracy, I call this the 'threat of algocracy'. The article clarifies the nature of this threat and addresses two possible solutions (named, respectively, 'resistance' and 'accommodation'). It is argued that neither solution is likely to be successful, at least not without risking many other things we value about social decision-making. The result is a somewhat pessimistic conclusion in which we confront the possibility that we are creating decision-making processes that constrain and limit opportunities for human participation.



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Short-Term Stability of Whole Blood Polyunsaturated Fatty Acid Content on Filter Paper During Storage at −28 °C

Abstract

Finger or heel-pricked blood sampling for fatty acid analysis is suitable especially in newborn infants where blood sampling is difficult and phlebotomy for research can be unethical. The aim of this study was to evaluate dried blood long chain polyunsaturated fatty acids (LC-PUFA) stability during storage at −28 °C. We collected 12 blood cord samples that were analyzed immediately after blood drawing, with and without drying the blood on filter paper. Dried samples were then analyzed 7 days and 1, 3, and 6 months after collection. Butylated hydroxytoluene was added to all samples. Fatty acid composition and 13C enrichment were measured by gas chromatography and by gas chromatography-isotope ratio mass spectrometry, respectively. The fatty acid composition, expressed in mol%, of the major LC-PUFA at day 7 was not statistically different from time 0, however lower values were found by the first month of storage. The 13C enrichment of 20:4n-6 and 22:6n-3 did not differ during the whole study period. LC-PUFA analysis from dried umbilical cord blood in neonates should be performed within a week, major losses of LC-PUFA occur afterwards. However, fatty acids obtained from dried blood maintain their 13C enrichment value for up to 6 months and thus these samples are suitable for natural abundance isotopic studies.



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Measuring Delay Discounting in Humans Using an Adjusting Amount Task

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Delay discounting refers to a decline in the value of a reward when it is delayed relative to when it is immediately available. We outline a computer-based delay discounting task that is easy to implement and allows for the quantification of the degree of delay discounting in human participants.

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Use of the data system for field management of a clinical study conducted in Kolkata, India

Designing an appropriate data system is important to the success of a clinical study. However, little information is available on this topic. We share our experiences on designing, developing, and implementat...

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Solitary langerhans cell histiocytosis in an adult: case report and literature review

Langerhans cell histiocytosis (LCH) is a disease that often affects children, but can also occur in adults and smokers. Oral manifestations are unusual and are characterized by bone pain, tooth mobility, necro...

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Carbon dioxide receptor genes and their expression profile in Diabrotica virgifera virgifera

Diabrotica virgifera virgifera, western corn rootworm, is one of the most devastating species in North America. D. v. virgifera neonates crawl through the soil to locate the roots on w...

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Combining Multiple Data Acquisition Systems to Study Corticospinal Output and Multi-segment Biomechanics

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The use of transcranial magnetic stimulation (TMS) to study human motor control requires the integration of data acquisition systems to control TMS delivery and simultaneously record human behavior. The present manuscript provides a detailed methodology for integrating data acquisition systems for the purpose of investigating human movement via TMS.

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Safety and efficacy of panretinal photocoagulation in patients with high-risk proliferative diabetic retinopathy using pattern scan laser versus conventional YAG laser

Publication date: Available online 9 January 2016
Source:The Kaohsiung Journal of Medical Sciences
Author(s): Recep Göktuğ Seymenoğlu, Mahmut Oğuz Ulusoy, Esin Fatma Başer
The purpose of the study was to compare the results of panretinal photocoagulation (PRP) using the pattern scan laser (PASCAL) in a single setting versus multiple sessions of standard YAG laser in patients with proliferative diabetic retinopathy. Charts of 35 eyes that were treated with the PASCAL and an equal number of eyes that were treated with conventional laser were retrospectively reviewed. The whole PRP treatment was performed in one session in the PASCAL group, whereas all the patients in the conventional-laser group completed the entire PRP treatment in two or three sessions. Persistence and/or recurrence of neovascularization, complications encountered, total number of laser spots, and mean power used were compared. Patients treated with the PASCAL received significantly higher number of laser spots than those treated with conventional laser (2885 vs. 1642, p < 0.001). The PASCAL and conventional-laser systems required an average power of 650 mW and 330 mW, respectively (p < 0.001). Patients treated with the PASCAL showed similar rates of treatment failure within 12 months of follow-up compared with patients treated with conventional laser (14% vs. 11%, p > 0.05). In the PASCAL group, vitreous hemorrhage, neovascular glaucoma, retinal hemorrhage, and choroidal detachment were reported in two, two, one, and two patients, respectively, whereas only one each vitreous hemorrhage and neovascular glaucoma were encountered in the conventional-laser group. Our study reports that single-session PRP with the PASCAL has similar efficacy compared with conventional laser, and has a favorable side-effect profile.



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