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Osiurak and Reynaud do not explain the evolutionary emergence and development of the elephant in the room, that is, technical cognition. We first argue that there is a tight correlation between the evolution of cumulative technological culture (CTC) and the evolution of reasoning about abstract forces. Second, intentional teaching plays a greater role in CTC evolution than acknowledged in the target article.
Immigrant children in Denmark differ greatly in educational outcomes. This study examined whether systematic differences in majority language (L2) and preliteracy skills are apparent already at ages 2–6 in immigrant children in Denmark across regional immigration background. Danish language and preliteracy skills in 1,211 immigrant children in four regional groups (based on maternal origin) and 11,259 native Danish nonimmigrant children, all enrolled in Danish childcare centers, were assessed using an age- and gender-normed language assessment instrument. Hierarchical linear models showed that all four immigrant groups scored significantly lower than the native Danish group; the negative coefficients diminished but remained significant when socioeconomic background and having a native Danish father were controlled for. In addition, even with these controls, significant differences existed between some of the immigrant groups, suggesting that factors relating to regional immigrant background were important sources of differences in L2 development. A greater immigrant disadvantage for language than preliteracy skills was found; two immigrant groups did not differ significantly from the nonimmigrant Danish group for preliteracy skills. The results suggest that measures to reduce inequalities in long-term educational achievement between immigrant groups should be taken already before school with a particular focus on L2 language skills.
The Grönhögen-2015 core drilling on southern Öland, Sweden, penetrated 50.15 m of Cambrian Series 3, Furongian and Lower–Middle Ordovician strata. The Cambrian succession includes the Äleklinta Member (upper Stage 5) of the Borgholm Formation and the Alum Shale Formation (Guzhangian–Tremadocian). Agnostoids and trilobites allowed subdivision of the succession into eight biozones, in ascending order: the uppermost Cambrian Series 3 (Guzhangian) Agnostus pisiformis Zone and the Furongian Olenus gibbosus, O. truncatus, Parabolina spinulosa, Sphaerophthalmus? flagellifer, Ctenopyge tumida, C. linnarssoni and Parabolina lobata zones. Conspicuous lithologic unconformities and the biostratigraphy show that the succession is incomplete and that there are several substantial gaps of variable magnitudes. Carbon isotope analyses (δ13Corg) through the Alum Shale Formation revealed two globally significant excursions: the Steptoean Positive Carbon Isotope Excursion (SPICE) in the lower–middle Paibian Stage, and the negative Top of Cambrian Excursion (TOCE), previously referred to as the HERB Event, in Stage 10. The δ13Corg chemostratigraphy is tied directly to the biostratigraphy and used for an improved integration of these excursions with the standard agnostoid and trilobite zonation of Scandinavia. Their relations to that of coeval successions in Baltoscandia and elsewhere are discussed. The maximum amplitudes of the SPICE and TOCE in the Grönhögen succession are comparable to those recorded in drill cores retrieved from Scania, southern Sweden. The results of this study will be useful for assessing biostratigraphic relations between shale successions and carbonate facies on a global scale.
The development of the helium ion microscope (HIM) enables the imaging of both hard, inorganic materials and soft, organic or biological materials. Advantages include outstanding topographical contrast, superior resolution down to <0.5 nm at high magnification, high depth of field, and no need for conductive coatings. The instrument relies on helium atom adsorption and ionization at a cryogenically cooled tip that is atomically sharp. Under ideal conditions this arrangement provides a beam of ions that is stable for days to weeks, with beam currents in the order of picoamperes. Over time, however, this stability is lost as gaseous contamination builds up in the source region, leading to adsorbed atoms of species other than helium, which ultimately results in beam current fluctuations. This manifests itself as horizontal stripe artifacts in HIM images. We investigate post-processing methods to remove these artifacts from HIM images, such as median filtering, Gaussian blurring, fast Fourier transforms, and principal component analysis. We arrive at a simple method for completely removing beam current fluctuation effects from HIM images while maintaining the full integrity of the information within the image.
To determine whether hydrogen peroxide vapor (HPV) could be used to decontaminate caliciviruses from surfaces in a patient room.
Feline calicivirus (FCV) and murine norovirus (MNV) were used as surrogate viability markers to mimic the noncultivable human norovirus. Cell culture supernatants of FCV and MNV were dried in triplicate 35-mm wells of 6-well plastic plates. These plates were placed in various positions in a nonoccupied patient room that was subsequently exposed to HPV. Control plates were positioned in a similar room but were never exposed to HPV.
Virucidal activity was measured in cell culture by reduction in 50% tissue culture infective dose titer for FCV and by both 50% tissue culture infective dose titer and plaque reduction for MNV.
Neither viable FCV nor viable MNV could be detected in the test room after HPV treatment. At least 3.65 log reduction for FCV and at least 3.67 log reduction for MNV were found by 50% tissue culture infective dose. With plaque assay, measurable reduction for MNV was at least 2.85 log units.
The successful inactivation of both surrogate viruses indicates that HPV could be a useful tool for surface decontamination of a patient room contaminated by norovirus. Hence nosocomial spread to subsequent patients can be avoided.
This article discusses the relation between knowing, learning and teaching in relation to early Palaeolithic technologies. We begin by distinguishing between three kinds of knowledge: knowing how, knowing what and knowing that. We discuss the relation between these types of knowledge and different forms of learning and long-term memory systems. On the basis of this analysis, we present three types of teaching: (1) helping and correcting; (2) showing; and (3) explaining. We then use this theoretical framework to suggest what kinds of teaching are required for the pre-Oldowan, the Oldowan, the early Acheulean and the late Acheulean stone-knapping technologies. As a general introductory overview to this special section, the text concludes with a brief presentation of the papers included.
We argue that Kline's analysis does not account for the evolutionary mechanisms that can explain the uniqueness of human teaching. We suggest that data should be complemented by an analysis of archaeological material with respect to what forms of teaching are required for the transmission of technologies over generations.
The Next Generation Transit Survey (NGTS) is a new ground-based survey for transiting exoplanets. Our primary goal is to find the first statistically-significant sample of Neptunes and super-Earths that are bright enough for radial velocity confirmation. By measuring precise masses and radii we will constrain the bulk composition and internal structure of planets that span the transition between the gas giants and terrestrial planets. Our brightest exoplanets will also be suitable for atmospheric characterisation with large facilities such as the VLT, JWST and the E-ELT. NGTS construction began in June 2013, and the survey is due to commence in 2014.
Brain white matter changes (WMC) and depressive symptoms are linked, but the directionality of this association remains unclear.
To investigate the relationship between baseline and incident depression and progression of white matter changes.
In a longitudinal multicentre pan-European study (Leukoaraiosis and Disability in the elderly, LADIS), participants aged over 64 underwent baseline magnetic resonance imaging (MRI) and clinical assessments. Repeat scans were obtained at 3 years. Depressive outcomes were assessed in terms of depressive episodes and the Geriatric Depression Scale (GDS). Progression of WMC was measured using the modified Rotterdam Progression scale.
Progression of WMC was significantly associated with incident depression during year 3 of the study (P = 0.002) and remained significant after controlling for transition to disability, baseline WMC and baseline history of depression. There was no significant association between progression of WMC and GDS score, and no significant relationship between progression of WMC and history of depression at baseline.
Our results support the vascular depression hypothesis and implicate WMC as causal in the pathogenesis of late-life depression.
Angle of arrival (AOA), time of arrival (TOA), and frequency of arrival (FOA) can be measured for a signal from multiple platforms. By combining such measurements it is possible to obtain high-accuracy emitter position estimates. This requires a data link with low latency and sufficient data-rate, and synchronization of the platforms in space, time, and search pattern. Typically several of the platforms will have to make their measurements in the radar sidelobes that require very high receiver sensitivity. This paper focuses on discussing how the sensitivity can be improved using antenna gain or signal processing.
This chapter focuses on visual complaints using the case of a 53-year-old woman who reports difficulties over the past 6 months in handling her work as a specialized clothes cutter in a garment factory. A quantified regional perfusion study using 99mTc SPECT eleven months after onset of symptoms showed significant hypoperfusion of the left parieto-temporal regions and very slight of the right parietal region. This was unchanged on repeat examination eight months later. The initial diagnostic impression was a focal cognitive deficit related to early Alzheimer's disease, non-familial. Atypical presentations of Alzheimer's disease account for about 15% of cases. This case falls under the umbrella of posterior cortical atrophy, first described by Benson et al. in 1988, usually presenting with visuospatial difficulties including visual fields defects. Donepezil was given and well tolerated up to 10 mg a day.
Large-scale aetiological studies of obesity and its pathological consequences require accurate measurements of adipose mass, distribution and subtype. Here, we compared the validity of three abdominal obesity assessment methods (dual-energy X-ray absorptiometry (DXA), ultrasound and anthropometry) against the gold-standard method of computed tomography (CT) in twenty-nine non-diseased middle-aged men (BMI 26·5 (sd 3·1) kg/m2) and women (BMI 25·5 (sd 3·2) kg/m2). Assessments of adipose mass (kg) and distribution (total subcutaneous (TSAT), superficial subcutaneous (SSAT), deep subcutaneous (DSAT) and visceral (VAT)) were obtained. Spearman's correlations were performed adjusted for age and sex. VAT area that was assessed using ultrasound (r 0·79; P < 0·0001) and waist circumference (r 0·85; P < 0·0001) correlated highly with VAT from CT, as did BMI (r 0·67; P < 0·0001) and DXA (r 0·70; P < 0·0001). DXA (r 0·72; P = 0·0004), BMI (r 0·71; P = 0·0003), waist circumference (r 0·86; P < 0·0001) and ultrasound (r 0·52; P = 0·015) were less strongly correlated with CT TSAT. None of the comparison measures of DSAT was strongly correlated with CT DSAT (all r approximately 0·50; P < 0·02). BMI (r 0·76; P < 0·0001), waist circumference (r 0·65; P = 0·002) and DXA (r 0·75; P < 0·0001) were all fairly strongly correlated with the CT measure of SSAT, whereas ultrasound yielded a weaker yet statistically significant correlation (r 0·48; P = 0·03). Compared with CT, visceral and subcutaneous adiposity can be assessed with reasonable validity using waist circumference and BMI, respectively. Ultrasound or DXA does not generally provide substantially better measures of these traits. Highly valid assessments of DSAT do not appear to be possible with surrogate measures. These findings may help guide the selection of measures for epidemiological studies of obesity.
GALEV evolutionary synthesis models describe the evolution of stellar populations in general, of star clusters as well as of galaxies, both in terms of resolved stellar populations and of integrated light properties over cosmological timescales of >13 Gyr from the onset of star formation shortly after the Big Bang until today. A new web-interface now allows to run customized GALEV models with user-defined parameters. This web-interface, all data, and many more features to come, can be found at http://www.galev.org.
A novel cryogenic electrostatic storage device consisting of two ion-beam storage rings with a common straight section for studies of interactions between oppositely charged ions at low and well-defined relative velocities is under construction at Stockholm University. Here we consider the prospect of using this new tool to measure cross-sections and rate coefficients for mutual neutralization reactions of importance in interstellar ion chemistry in general and specifically in cosmic pre-biotic ion chemistry.