Стан збереження та проблеми охорони культурної спадщини на Путивльщині

In a 2010 paper Aziz, Chergui and colleagues observe fluorescence yield (FY) detected X-ray absorption spectra that are concentration-dependent and show both dips and peaks. In this comment I will show that all observed spectral features are a consequence of the relative ratio of background and edge emission, combined with energy-dependent X-ray emission decay channels

Uncatalyzed synthesis, thermal and mechanical properties of polyurethanes based on poly(epsilon-caprolactone) and 1,4-butane diisocyanate with uniform hard segment

Polyurethanes based on poly(epsilon-caprolactone) (PCL) (750-2800g/mol) and 1,4-butane diisocyanate (BDI) with different soft segment lengths and constant uniform hard segment length were synthesized in absence of catalysts for the production of a degradable meniscus scaffold. First the polyesterdiols were endcapped with BDI yielding a macrodiisocyanate with a minimal amount of side reactions and a functionality of 2.0. Subsequently, the macrodiisocyanates were extended with 1,4-butanediol in order to obtain the corresponding polyurethane. The polyurethanes had molecular weights between 78 and 160 kg/mol.Above molar masses of 1900 g/mol of the polyesterdiol crystalline PCL was found while the hard segment showed an increase in melting point from 78 to 122 degreesC with increasing hard segment content. It was estimated that the percentage crystallinity of the hard segment varied between 92 and 26%. The Young's modulus varied between 30 and 264 MPa, the strain at break varied between 870 and 1200% and tear strengths varied between 97 and 237 kJ/m(2). (C) 2004 Elsevier Ltd. All rights reserved.</p

Prediction of 90-day mortality in older patients after discharge from an emergency department: a retrospective follow-up study

Background: Older people frequently attend the emergency department (ED) and have a high risk of poor outcome as compared to their younger counterparts. Our aim was to study routinely collected clinical parameters as predictors of 90-day mortality in older patients attending our ED. Methods: We conducted a retrospective follow-up study at the Leiden University Medical Center (The Netherlands) among patients aged 70 years or older attending the ED in 2012. Predictors were age, gender, time and way of arrival, presenting complaint, consulting medical specialty, vital signs, pain score and laboratory testing. Cox regression analyses were performed to analyse the association between these predictors and 90-day mortality. Results: Three thousand two hundred one unique patients were eligible for inclusion. Ninety-day mortality was 10.5 % for the total group. Independent predictors of mortality were age (hazard ratio [HR] 1.06, 95 % confidence interval [95 % CI] 1.04-1.08), referral from another hospital (HR 2.74, 95 % CI 1.22-6.11), allocation to a non-surgical specialty (HR: 1.55, 95 % CI 1.13-2.14), increased respiration rate (HR up to 2.21, 95 % CI 1.25-3.92), low oxygen saturation (HR up to 1.96, 95 % CI 1.19-3.23), hypothermia (HR 2.27, 95 % CI 1.28-4.01), fever (HR 0.43, 95 % CI 0.24-0.75), high pain score (HR 1.55, 95 % CI 1.03-2.32) and the indication to perform laboratory testing (HR 3.44, 95 % CI 2.13-5.56). Conclusions: Routinely collected parameters at the ED can predict 90-day mortality in older patients presenting to the ED. This study forms the first step towards creating a new and simple screening tool to predict and improve health outcome in acutely presenting older patients

Predicting mortality in acutely hospitalized older patients: a retrospective cohort study

Acutely hospitalized older patients have an increased risk of mortality, but at the moment of presen- tation this risk is difficult to assess. Early identification of patients at high risk might increase the awareness of the physician, and enable tailored decision-making. Existing screening instruments mainly use either geriatric factors or severity of disease for prognostication. Predictive perfor- mance of these instruments is moderate, which hampers successive interventions. We conducted a retrospective cohort study among all patients aged 70 years and over who were acutely hospitalized in the Acute Medical Unit of the Leiden University Medical Center, the Netherlands in 2012. We developed a prediction model for 90-day mor- tality that combines vital signs and laboratory test results reflecting severity of disease with geriatric factors, repre- sented by comorbidities and number of medications. Among 517 patients, 94 patients (18.2 %) died within 90 days after admission. Six predictors of mortality were included in a model for mortality: oxygen saturation, Charlson comorbidity index, thrombocytes, urea, C-reac- tive protein and non-fasting glucose. The prediction model performs satisfactorily with an 0.738 (0.667–0.798). Using this model, 53 % of the patients in the highest risk decile ( N = 51) were deceased within 90 days. In conclusion, we are able to predict 90-day mortality in acutely hospitalized older patients using a model with directly available clinical data describing disease severity and geriatric factors. After further validation, such a model might be used in clinical decision making in older patients

Solid-state NMR applied to photosynthetic light-harvesting complexes

This short review describes how solid-state NMR has provided a mechanistic and electronic picture of pigment–protein and pigment–pigment interactions in photosynthetic antenna complexes. NMR results on purple bacterial antenna complexes show how the packing of the protein and the pigments inside the light-harvesting oligomers induces mutual conformational stress. The protein scaffold produces deformation and electrostatic polarization of the BChl macrocycles and leads to a partial electronic charge transfer between the BChls and their coordinating histidines, which can tune the light-harvesting function. In chlorosome antennae assemblies, the NMR template structure reveals how the chromophores can direct their self-assembly into higher macrostructures which, in turn, tune the light-harvesting properties of the individual molecules by controlling their disorder, structural deformation, and electronic polarization without the need for a protein scaffold. These results pave the way for addressing the next challenge, which is to resolve the functional conformational dynamics of the lhc antennae of oxygenic species that allows them to switch between light-emitting and light-energy dissipating states

Full vector archaeomagnetic records from Anatolia between 2400 and 1350 BCE: Implications for geomagnetic field models and the dating of fires in antiquity

Anatolia, as one of the busiest crossroads of ancient civilizations, provides an ideal platform for archaeomagnetic studies. Previous results from the Middle East have suggested the occurrence of a strong peak in geomagnetic intensity at ∼1000 BCE associated with dramatic field strength variations that could require a radical rethinking of geodynamo theory. The behavior of the field in the centuries preceding this peak remains poorly constrained, however. Here we present the results of full-vector archaeomagnetic experiments performed on 18 sets of samples from three archaeological sites belonging to Assyrian Trade Colony and Hittite periods. Associated rock magnetic analyses showed that the major magnetic carrier is magnetite chemically stable up to 700 °C and the magnetic mineral assemblage is composed mostly of non-interacting PSD grains. The directional results are compared with existing data and with the most recent global geomagnetic field models pfm9k.1b and SHA.DIF.14k. The directions are in remarkably good agreement with SHA.DIF.14k which is based on archaeomagnetic and lava flow data. Together with our earlier results from Anatolia, we triple the existing database of directions for the 700 year long period 2200–1500 BCE, over a large region from Greece to Azerbaijan, and from Moldavia/Ukraine to Egypt. Three archaeointensity methods: thermal IZZI-Thellier, microwave Thellier and the multi-specimen protocol (MSP) produced virtual axial dipole moment estimates () that are somewhat higher than contemporaneous (regional and global) data and model predictions suggesting that the field was already substantially stronger than today more than 800 years prior to the reported peak. In addition to constraining geomagnetic variability, our data also allow us to assign relative dates to inferred fire events in the Assyrian Trade Colony Period sites. This allows us to conclude that the fire events at the largest site, Kültepe, were not all contemporaneous with one another and with the abandonment of the site as has been previously hypothesized

Extensive DRB region diversity in cynomolgus macaques: recombination as a driving force

The DR region of primate species is generally complex and displays diversity concerning the number and combination of distinct types of DRB genes present per region configuration. A highly variable short tandem repeat (STR) present in intron 2 of nearly all primate DRB genes can be utilized as a quick and accurate high through-put typing procedure. This approach resulted previously in the description of unique and haplotype-specific DRB-STR length patterns in humans, chimpanzees, and rhesus macaques. For the present study, a cohort of 230 cynomolgus monkeys, including self-sustaining breeding groups, has been examined. MtDNA analysis showed that most animals originated from the Indonesian islands, but some are derived from the mainland, south and north of the Isthmus of Kra. Haplotyping and subsequent sequencing resulted in the detection of 118 alleles, including 28 unreported ones. A total of 49 Mafa-DRB region configurations were detected, of which 28 have not yet been described. Humans and chimpanzees possess a low number of different DRB region configurations in concert with a high degree of allelic variation. In contrast, however, allelic heterogeneity within a given Mafa-DRB configuration is even less frequently observed than in rhesus macaques. Several of these region configurations appear to have been generated by recombination-like events, most probably propagated by a retroviral element mapping within DRB6 pseudogenes, which are present on the majority of haplotypes. This undocumented high level of DRB region configuration-associated diversity most likely represents a species-specific strategy to cope with various pathogens