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The production of lime plaster is especially important as a technological development in human prehistory as it requires advanced knowledge and skills to transform rocks to a plastic yet durable material. The large-scale production of lime plaster is considered a development of farming societies during the Neolithic period around 10,000 years ago. To date, the archaeological evidence from the Middle and Late Epipalaeolithic in the southern Levant (c. 17,000–11,500 cal BP) indicates that only initial production of partially carbonated lime plaster was performed by Palaeolithic foragers. Our study analysed lime plaster covering burials at a Natufian cemetery in Nahal Ein Gev II, dating to 12,000 years ago. Using infrared spectroscopy and soil micromorphology we show how this lime plaster is of an unprecedented high quality and we reconstruct its production. The results exhibit a technological leap forward at the end of the Palaeolithic. We provide a new model for understanding the evolutionary paths of lime plaster technology during the Palaeolithic–Neolithic transition.
Specialized early intervention (EI) following a first episode of psychosis (FEP) are effective at reducing negative symptoms, although its trajectory warrants systematic assessment. However, findings are equivocal as to whether extended gains are made post 2 years of EI and whether there is additional benefit of extending EI for an additional 3 years.
Data on 178 FEP patients, from a randomized controlled trial of a 3-year extension of EI service v. transfer to regular care following 2 years of EI service, were used for this report. Repeated measures analysis of variance were conducted separately for the initial 2 years of treatment in an EI service, and for the 3-year post-randomization to examine trajectories of negative symptoms over the two periods in the two arms of the study.
There were significant improvements in total negative symptoms over the first 2 years of EI F(4.612, 797.905) = 25.263, p < 0.001 and in domains of ‘expressivity’ and ‘motivation’. In the following 3 years, there were further significant improvements in negative symptoms F(4.318, 759.908) = 4.182, p = 0.002 with no difference between groups F(4.318, 759.908) = 1.073, p = 0.371. Changes in negative symptoms over the extension period were driven by expressivity F(4.01, 674.73) = 7.19, p < 0.01, but not motivation F(6.58, 1112.18) = 0.95, p = 0.46.
Negative symptoms improve significantly over the first 2 years of EI. Subsequent amelioration was largely the result of expressivity. Motivation deficits remained stable. Extended EI offered no advantage over regular care post-randomization.
We show that if a unital injective endomorphism of a
-algebra admits a transfer operator, then both of them are compressions of mutually inverse automorphisms of a bigger algebra. More generally, every interaction group – in the sense of Exel – extending an action of an Ore semigroup by injective unital endomorphisms of a
-algebra, admits a dilation to an action of the corresponding enveloping group on another unital
-algebra, of which the former is a
-subalgebra: the interaction group is obtained by composing the action with a conditional expectation. The dilation is essentially unique if a certain natural condition of minimality is imposed, and it is faithful if and only if the interaction group is also faithful.
We consider two independent and stationary measures over
is a finite or countable alphabet. For each pair of
-strings in the product space we define
as the length of the shortest path connecting one of them to the other. Here the paths are generated by the underlying dynamic of the measures. If they are ergodic and have positive entropy we prove that, for almost every pair of realizations
is concentrated in one, as
diverges. Under mild extra conditions we prove a large-deviation principle. We also show that the fluctuations of
converge (only) in distribution to a non-degenerate distribution. These results are all linked to a quantity that computes the similarity between those two measures. This is the so-called divergence between two measures, which is also introduced. Several examples are provided.
Men who have sex with men (MSM) have an increased incidence of pathogens transmitted by the oro-fecal route. Hepatitis E virus (HEV) is an emerging cause of acute hepatitis and fecal shedding is observed during primary infection. We investigated whether MSM are at increased risk of HEV infection. Subjects who attended a sexually transmitted infection clinic in Brussels and had an HIV test performed between 1 June 2014 and 15 January 2016 were identified. A total of 576 samples were retrospectively screened for both total HEV IgG and HEV RNA. Samples positive for IgG were tested for IgM. MSM proportion was 31·1% (179/576). Overall HEV IgG prevalence was 9·03% (52/576) and was identical in MSM and heterosexual subjects. Among the IgG positive samples, 2/52 (3·84%) samples (both women) were positive for anti-HEV IgM. No sample was positive for HEV RNA. Age over 35 was the only risk factor significantly associated with HEV seropositivity (OR 2·07; 95% CI 1·16–3·67). In conclusion, MSM were not found to have an increased prevalence of HEV as previously reported in other European countries suggesting distinct dynamics of HEV infection in this group across Europe and increased age was associated with a higher risk of seropositivity.
The relationship of statues to the deities they represent is reflected in the special treatments they were often accorded during and after their primary use and display. In 2014 an unusual favissa—an intentionally hidden cache of religious objects—was discovered in the temple of Ptah at Karnak in Egypt. Such caches are generally poorly documented and difficult to date. The favissa contained numerous fragmentary statuettes and figurines, including 14 representing Osiris, carefully arranged around a larger central statue of Ptah. By comparing this cache with evidence from other Egyptian favissae, a hypothesis is proposed to explain the creation of such caches: the Osirian burial of an artefact, in this case the deposition of the ‘deceased’ statue of the god Ptah and its assimilation with Osiris, the god of rebirth.
There is a paucity of Palaeolithic art in the southern Levant prior to 15 000 years ago. The Natufian culture (15 000–11 500 BP; Grosman 2013) marks a threshold in the magnitude and diversity of artistic manifestations (Bar-Yosef 1997). Nevertheless, depictions of the human form remain rare—only a few representations of the human face have been reported to date. This article presents a 12 000-year-old example unearthed at the Late Natufian site of Nahal Ein Gev II (NEGII), just east of the Sea of Galilee, Israel (Figure 1). The object provides a glimpse into Natufian conventions of human representation, and opens a rare opportunity for deeper understanding of the Natufian symbolic system.
Wheat is an important crop in the highlands of Northern Ethiopia and climate change is expected to be a major threat to wheat productivity. However, the potential impacts of climate change and adaptation on wheat yield has not been documented for this region. Wheat field experiments were carried out during the 2011–2013 cropping seasons in Northern Ethiopia to: (1) calibrate and evaluate Agricultural Production Systems sIMulator (APSIM)-wheat model for exploring the impacts of climate change and adaptation on wheat yield; (2) explore the response of wheat cultivar/s to possible change in climate and carbon dioxide (CO2) under optimal and sub-optimal fertilizer application and (3) assess the impact of climate change and adaptation practices on wheat yield based on integration of surveyed field data with climate simulations using multi-global climate models (GCMs; for short- and mid-term periods) for the Hintalo-Wajrat areas of Northern Ethiopia. The treatments were two levels of fertilizer (optimal and zero fertilization); treatments were replicated three times and arranged in a randomized complete block design. All required information for model calibration and evaluation were gathered from experimental studies. In addition, a household survey was conducted in 2012 in Northern Ethiopia. Following model calibration and performance testing, response of wheat to various nitrogen (N) fertilizer rates, planting date, temperature and combinations of other climate variables and CO2 were assessed. Crop simulations were conducted with future climate scenarios using 20 different GCMs and compared with a baseline. In addition, simulations were carried out using climate data from five different GCM with and without climate change adaptation practices. The simulated yield showed clear responses to changes in temperature, N fertilizer and CO2. Regardless of choice of cultivar, increasing temperatures alone (by up to 5 °C compared with the baseline) resulted in reduced yield while the addition of other factors (optimal fertilizer with elevated CO2) resulted in increased yield. Considering optimal fertilizer (64 kg/ha N) as an adaptation practice, wheat yield in the short-term (2010–2039) and mid-term (2040–2069) may increase at least by 40%, compared with sub-optimal N levels. Assuming CO2 and present wheat management is unchanged, simulation results based on 20 GCMs showed that median wheat yields will reduce by 10% in the short term and by 11% in the mid-term relative to the baseline data, whereas under changed CO2 with present management, wheat yield will increase slightly, by up to 8% in the short term and by up to 11% in the mid-term period, respectively. Wheat yield will substantially increase, by more than 100%, when simulated based on combined use of optimal planting date and fertilizer applications. Increased temperature in future scenarios will cause yield to decline, whereas CO2 is expected to have positive impacts on wheat yield.
We have developed and tested a code that computes the evolution of a mixed system of gas and dark matter in expanding world models. The gravitational forces are calculated with the Adaptative P3M algorithms developed by H. Couchmann, 1993. The calculation of gas forces follow the standard SPH formalism (Monaghan, 1989).
Using the eagle cosmological simulation of galaxy formation we test the ability of the ΛCDM cosmological model to reproduce the Tully-Fisher relation (TFR) and its redshift evolution. We find that our simulated galaxies follow a TFR that is in good agreement with observed results up to z = 1, indicating no evolution in the slope and a weak decrease in the zero-point.
Despite the widespread dissemination of HIV information through public awareness campaigns in Mali, disclosing seropositivity to one's steady sexual partner (SSP) remains difficult for people living with HIV (PLHIV). Disclosure is a public health concern with serious implications and is also strongly linked to the quality of life of PLHIV. This study aimed to analyse factors associated with voluntary HIV disclosure to one's SSP, using a community-based cross-sectional study on 300 adult PLHIV in contact with a Malian community-based organization working in the field of AIDS response. A 125-item questionnaire was administered by trained personnel to study participants between May and October 2011. Analysis was restricted to the 219 participants who both reported having a SSP and answered to the question on disclosure to their SSP. A weighted multivariate logistic regression was used to determine variables independently associated with disclosure. In total, 161 participants (73%) reported HIV disclosure to their SSP. Having children (odds ratio [95% confidence interval]: 4.52 [1.84–11.12]), being accompanied to the survey site (3.66 [1.00–13.33]), knowing others who had publicly declared their seropositivity (3.12 [1.59–6.12]), having higher self-esteem (1.55 [1.09–2.19]) and using means other than anti-retroviral treatment to treat HIV (0.33 [0.11–1.00]) were independently associated with disclosure. This study identified several factors that should be considered for the design of interventions aimed at facilitating disclosure if/when desired in this cultural context.
This paper aims at investigating the resonance frequencies and stability of a long Graphene Nano-Ribbon (GNR) carrying electric current. The governing equation of motion is obtained based on the Euler-Bernoulli beam model along with Hamilton’s principle. The transverse force distribution on the GNR due to the interaction of the electric current with its own magnetic field is determined by the Biot-Savart and Lorentz force laws. Using Galerkin’s method, the governing equation is solved and the effect of current strength and dimensions of the GNR on the stability and resonance frequencies are investigated.