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Thin HfO2films atomic layer deposited from hafnium alkyl amide and oxygen plasma were analysed using spectroscopic ellipsometry and X-ray reflectivity. Low refractive index of the material for samples with less than 30 nm thickness marks the index inhomogeneity at the first stage of growth. The transition from rising density to a more stable growth takes place at about 10 to 25 nm film thickness. HfO2films used for resistive switching experiments demonstrate either clockwise or counterclockwise behaviour depending on the film thickness. The reason for this may be the disruption of the conductive filament at different metal-insulator interfaces, which could be favoured by several mechanisms.

AbstractThis article presents managed honey bee colony loss rates over winter 2019/20 resulting from using the standardised COLOSS questionnaire in 37 countries. Six countries were from outside Europe, including, for the first time in this series of articles, New Zealand. The 30,491 beekeepers outside New Zealand reported 4.5% of colonies with unsolvable queen problems, 11.1% of colonies dead after winter and 2.6% lost through natural disaster. This gave an overall colony winter loss rate of 18.1%, higher than in the previous year. The winter loss rates varied greatly between countries, from 7.4% to 36.5%. 3216 beekeepers from New Zealand managing 297,345 colonies reported 10.5% losses for their 2019 winter (six months earlier than for other, Northern Hemisphere, countries). We modelled the risk of loss as a dead/empty colony or from unresolvable queen problems, for all countries except New Zealand. Overall, larger beekeeping operations with more than 50 colonies experienced significantly lower losses (p < 0.001). Migration was also highly significant (p < 0.001), with lower loss rates for operations migrating their colonies in the previous season. A higher proportion of new queens reduced the risk of colony winter loss (p < 0.001), suggesting that more queen replacement is better. All three factors, operation size, migration and proportion of young queens, were also included in a multivariable main effects quasi-binomial GLM and all three remained highly significant (p < 0.001). Detailed results for each country and overall are given in a table, and a map shows relative risks of winter loss at the regional level.

Recurrent models are a popular choice for video enhancement tasks such as video denoising or super-resolution. In this work, we focus on their stability as dynamical systems and show that they tend to fail catastrophically at inference time on long video sequences. To address this issue, we (1) introduce a diagnostic tool which produces input sequences optimized to trigger instabilities and that can be interpreted as visualizations of temporal receptive fields, and (2) propose two approaches to enforce the stability of a model during training: constraining the spectral norm or constraining the stable rank of its convolutional layers. We then introduce Stable Rank Normalization for Convolutional layers (SRN-C), a new algorithm that enforces these constraints. Our experimental results suggest that SRN-C successfully enforces stablility in recurrent video processing models without a significant performance loss.

Escherichia colirRNAs are post-transcriptionally modified at 36 positions but their modification enzymes are dispensable individually for growth, bringing into question their significance. However, a major growth defect was reported for deletion of the RlmE enzyme, which abolished a 2′Omethylation near the peptidyl transferase center (PTC) of the 23S rRNA. Additionally, an adjacent 80-nt “critical region” around the PTC had to be modified to yield significant peptidyl transferase activity in vitro. Surprisingly, we discovered that an absence of just two rRNA modification enzymes is conditionally lethal (at 20°C): RlmE and RluC. At a permissive temperature (37°C), this double knockout was shown to abolish four modifications and be defective in ribosome assembly, though not more so than the RlmE single knockout. However, the double knockout exhibited an even lower rate of tripeptide synthesis than did the single knockout, suggesting an even more defective ribosomal translocation. A combination knockout of the five critical-region-modifying enzymes RluC, RlmKL, RlmN, RlmM, and RluE (not RlmE), which synthesize five of the seven critical-region modifications and 14 rRNA and tRNA modifications altogether, was viable (minor growth defect at 37°C, major at 20°C). This was surprising based on prior in vitro studies. This five-knockout combination had minimal effects on ribosome assembly and frameshifting at 37°C, but greater effects on ribosome assembly and in vitro peptidyl transferase activity at cooler temperatures. These results establish the conditional essentiality of bacterial rRNA modification enzymes and also reveal unexpected plasticity of modification of the PTC region in vivo.

We aimed to describe epidemiology of diarrhea and cholestasis in critically ill patients and explore associations between these two conditions.

This article presents managed honey bee colony loss rates over winter 2018/19 resulting from using the standardised COLOSS questionnaire in 35 countries (31 in Europe). In total, 28,629 beekeepers supplying valid loss data wintered 738,233 colonies, and reported 29,912 (4.1%, 95% confidence interval (CI) 4.0–4.1%) colonies with unsolvable queen problems, 79,146 (10.7%, 95% CI 10.5–10.9%) dead colonies after winter and 13,895 colonies (1.9%, 95% CI 1.8–2.0%) lost through natural disaster. This gave an overall colony winter loss rate of 16.7% (95% CI 16.4–16.9%), varying greatly between countries, from 5.8% to 32.0%. We modelled the risk of loss as a dead/empty colony or from unresolvable queen problems, and found that, overall, larger beekeeping operations with more than 150 colonies experienced significantly lower losses (p < 0.001), consistent with earlier studies. Additionally, beekeepers included in this survey who did not migrate their colonies at least once in 2018 had significantly lower losses than those migrating (p < 0.001). The percentage of new queens from 2018 in wintered colonies was also examined as a potential risk factor. The percentage of colonies going into winter with a new queen was estimated as 55.0% over all countries. Higher percentages of young queens corresponded to lower overall losses (excluding losses from natural disaster), but also lower losses from unresolvable queen problems, and lower losses from winter mortality (p < 0.001). Detailed results for each country and overall are given in a table, and a map shows relative risks of winter loss at regional level.

We propose a distributed design method for decentralized control by exploiting the underlying sparsity properties of the problem. Our method is based on the chordal decomposition of sparse block matrices and the alternating direction method of multipliers (ADMM). We first apply a classical parameterization technique to restrict the optimal decentralized control into a convex problem that inherits the sparsity pattern of the original problem. The parameterization relies on a notion of strongly decentralized stabilization, and sufficient conditions are discussed to guarantee this notion. Then, chordal decomposition allows us to decompose the convex restriction into a problem with partially coupled constraints, and the framework of ADMM enables us to solve the decomposed problem in a distributed fashion. Consequently, the subsystems only need to share their model data with their direct neighbors, without needing central computation. Numerical experiments demonstrate the effectiveness of the proposed method.

Atomic layer deposited polycrystalline Cr2O3films grown from chromyl chloride and methanol were analysed using spectrophotometry, spectral ellipsometry and atomic force microscopy. The films possessed polycrystalline eskolaite structure with rough sublayer in contact with air. Using the positions and peak widths of the two visible absorption bands as fixed from absorption measurements, we could determine the optical dispersion of the film material in 1.3 – 6 eV energy region. A direct band gap of chromia film grown in these conditions was 3.2 eV, the other also direct absorption band with a gap of 5.15 eV was found situated in UV.

This short article presents loss rates of honey bee colonies over winter 2017/18 from 36 countries, including 33 in Europe, from data collected using the standardized COLOSS questionnaire. The 25,363 beekeepers supplying data passing consistency checks in total wintered 544,879 colonies, and reported 26,379 (4.8%, 95% CI 4.7–5.0%) colonies with unsolvable queen problems, 54,525 (10.0%, 95% CI 9.8–10.2%) dead colonies after winter and another 8,220 colonies (1.5%, 95% CI 1.4–1.6%) lost through natural disaster. This gave an overall loss rate of 16.4% (95% CI 16.1–16.6%) of honey bee colonies during winter 2017/18, but this varied greatly from 2.0 to 32.8% between countries. The included map shows relative risks of winter loss at regional level. The analysis using the total data-set confirmed findings from earlier surveys that smaller beekeeping operations with at most 50 colonies suffer significantly higher losses than larger operations (p < .001). Beekeepers migrating their colonies had significantly lower losses than those not migrating (p < .001), a different finding from previous research. Evaluation of six different forage sources as potential risk factors for colony loss indicated that intensive foraging on any of five of these plant sources (Orchards, Oilseed Rape, Maize, Heather and Autumn Forage Crops) was associated with significantly higher winter losses. This finding requires further study and explanation. A table is included giving detailed results of loss rates and the impact of the tested forage sources for each country and overall.

We present an individual biography of an adult woman from the 3rd millennium BC from the Eastern Baltic. Being a representative of a Corded Ware Culture she is considered one of the first documented cases carrying the early plague bacteria, Yersina pestis. The appearance, life, and death of this individual from Sope, NE Estonia, is provided through an application of a range of osteological and biomolecular analyses. The mortuary practices that accompanied her death are revealed through post-excavation archaeothanatological analysis. The position of bones within the grave indicates that her remains were handled differently from the known contemporary Corded Ware Culture inhumations. The mortuary treatment consisted of at least two phases that resulted in an imitation of a ‘proper’ flexed burial. Probably, the reburial of bones was undertaken during the Corded Ware period.

Titanium dioxide coatings of different thicknesses were deposited on the acid-treated multiwall carbon nanotubes (MWCNTs) using controlled atomic layer deposition (ALD). Pt nanoparticles (NP) were deposited on TiO2/MWCNT supports using two deposition methods, viz. sputter-deposition and photo-deposition. Scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) measurements revealed successful application of ALD for the deposition of TiO2. Both magnetron sputtering and photo-deposition were found to be efficient and well-controlled techniques for the deposition of Pt NPs on oxide-carbon support. Electrochemical decontamination and characterization of the catalysts surface was carried out by CO stripping and cyclic voltammetry in 0.1 M KOH solution. The prepared Pt-TiO2/MWCNT catalyst showed comparable oxygen reduction reaction (ORR) activity to that of commercial Pt/C (20 wt%), while long-term durability test revealed better durability of the prepared catalysts due to strong metal-support interaction.

In this short note we present comparable loss rates of honey bee colonies during winter 2016/2017 from 27 European countries plus Algeria, Israel and Mexico, obtained with the COLOSS questionnaire. The 14,813 beekeepers providing valid loss data collectively wintered 425,762 colonies, and reported 21,887 (5.1%, 95% confidence interval 5.0–5.3%) colonies with unsolvable queen problems and 60,227 (14.1%, 95% CI 13.8–14.4%) dead colonies after winter. Additionally we asked for colonies lost due to natural disaster, which made up another 6,903 colonies (1.6%, 95% CI 1.5–1.7%). This results in an overall loss rate of 20.9% (95% CI 20.6–21.3%) of honey bee colonies during winter 2016/2017, with marked differences among countries. The overall analysis showed that small operations suffered higher losses than larger ones (p < 0.001). Overall migratory beekeeping had no significant effect on the risk of winter loss, though there was an effect in several countries. A table is presented giving detailed results from 30 countries. A map is also included, showing relative risk of colony winter loss at regional level.

ABSTRACTThe endoribonuclease toxins of the E. colitoxin-antitoxin systems arrest bacterial growth and protein synthesis by targeting cellular mRNAs. As an exception, E. coliMazF was reported to cleave also 16S rRNA at a single site and separate an anti-Shine-Dalgarno sequence-containing RNA fragment from the ribosome. We noticed extensive rRNA fragmentation in response to induction of the toxins MazF and MqsR, which suggested that these toxins can cleave rRNA at multiple sites. We adapted differential RNA-sequencing to map the toxin-cleaved 5′- and 3′-ends. Our results show that the MazF and MqsR cleavage sites are located within structured rRNA regions and, therefore, are not accessible in assembled ribosomes. Most of the rRNA fragments are located in the aberrant ribosomal subunits that accumulate in response to toxin induction and contain unprocessed rRNA precursors. We did not detect MazF- or MqsR-cleaved rRNA in stationary phase bacteria and in assembled ribosomes. Thus, we conclude that MazF and MqsR cleave rRNA precursors before the ribosomes are assembled and potentially facilitate the decay of surplus rRNA transcripts during stress.

LPL hydrolyzes triglycerides in plasma lipoproteins. Due to the complex regulation mechanism, it has been difficult to mimic the physiological conditions under which LPL acts in vitro. We demonstrate that isothermal titration calorimetry (ITC), using human plasma as substrate, overcomes several limitations of previously used techniques. The high sensitivity of ITC allows continuous recording of the heat released during hydrolysis. Both initial rates and kinetics for complete hydrolysis of plasma lipids can be studied. The heat rate was shown to correspond to the release of fatty acids and was linearly related to the amount of added enzyme, either purified LPL or postheparin plasma. Addition of apoC-III reduced the initial rate of hydrolysis by LPL, but the inhibition became less prominent with time when the lipoproteins were triglyceride poor. Addition of angiopoietin-like protein (ANGPTL)3 or ANGPTL4 caused reduction of the activity of LPL via a two-step mechanism. We conclude that ITC can be used for quantitative measurements of LPL activity and interactions under in vivo-like conditions, for comparisons of the properties of plasma samples from patients and control subjects as substrates for LPL, as well as for testing of drug candidates developed with the aim to affect the LPL system.

In this short note we present comparable loss rates of honey bee colonies during winter 2015/16 from 29 countries, obtained with the COLOSS questionnaire. Altogether, we received valid answers from 19,952 beekeepers. These beekeepers collectively wintered 421,238 colonies, and reported 18,587 colonies with unsolvable queen problems and 32,048 dead colonies after winter. This gives an overall loss rate of 12.0% (95% confidence interval 11.8–12.2%) during winter 2015/16, with marked differences among countries. Beekeepers in the present study assessed 7.6% (95% CI 7.4–7.8%) of their colonies as dead or empty, and 4.4% (95% CI 4.3–4.5%) as having unsolvable queen problems after winter. The overall analysis showed that small operations suffered higher losses than larger ones. A table with detailed results and a map showing response and relative risks at regional level are presented.

Gallium oxide thin films, containing either α-Ga2O3or κ-Ga2O3crystalline phases, were grown by atomic layer deposition (ALD) by using GaI3and O3as precursors. The κ-Ga2O3phase was observed in the films grown on Si(1 0 0) at substrate temperatures ≥450 °C, while α-Ga2O3was obtained at temperatures ≥275 °C on α-Cr2O3seed layers deposited on Si(1 0 0). The seed layers with thicknesses down to 0.7 nm appeared to be sufficient to initiate the α-Ga2O3growth. The densities of 5.2–5.3 g/cm3for amorphous films deposited at the substrate temperatures 150–234 °C, 5.9−6.1 g/cm3for the films deposited on uncoated Si substrates at 450–550 °C, and 6.3−6.4 g/cm3for the films deposited on α-Cr2O3seed layers at 350–550 °C were determined from X-ray reflectometry measurements. The growth per cycle decreased from 0.17 to 0.05–0.09 nm with the growth temperature increase from 150 to 550 °C. Notably, the growth rates of α-Ga2O3films on α-Cr2O3seed layers were significantly higher at 350–450 °C than those of the films deposited on uncoated Si at the same temperatures, indicating that crystal structure influenced the growth per cycle in this ALD process. The concentration of iodine impurities did not exceed 3.2 at. % in the films deposited at 150 °C. With the growth-temperature increase to 350 °C, the concentration of impurities decreased to ≤0.04 at. % in the films grown on bare Si and ≤0.01 at. % in the films grown on α-Cr2O3seed layers.

In this paper, we further develop a recently proposed control method to switch a bistable system between its steady states using temporal pulses. The motivation for using pulses comes from biomedical and biological applications (e.g. synthetic biology), where it is generally difficult to build feedback control systems due to technical limitations in sensing and actuation. The original framework was derived for monotone systems and all the extensions relied on monotone systems theory. In contrast, we introduce the concept of switching function which is related to eigenfunctions of the so-called Koopman operator subject to a fixed control pulse. Using the level sets of the switching function we can (i) compute the set of all pulses that drive the system toward the steady state in a synchronous way and (ii) estimate the time needed by the flow to reach an epsilon neighborhood of the target steady state. Additionally, we show that for monotone systems the switching function is also monotone in some sense, a property that can yield efficient algorithms to compute it. This observation recovers and further extends the results of the original framework, which we illustrate on numerical examples inspired by biological applications.

A thin industrial corrosion-protection nanostructured coating for the Al alloy AA2024-T3 is demonstrated. The coating is prepared in a two-step process utilizing hard anodizing as a pre-treatment, followed by sealing and coating by atomic layer deposition (ALD). In the first step, anodizing in sulfuric acid at a low temperature converts the alloy surface into a low-porosity anodic oxide. In the second step, the pores are sealed and coated by low-temperature ALD using different metal oxides. The resulting nanostructured ceramic coatings are thoroughly characterized by cross-sectioning using a focused ion beam, followed by scanning electron microscopy, transmission electron microscopy, X-ray microanalysis, and nanoindentation and are tested via linear sweep voltammetry, electrochemical impedance spectroscopy, salt spray, and energetic atomic oxygen flow. The best thin corrosion protection coating, made by anodizing at 20 V, 1 °C and sealing and coating with amorphous Al2O3/TiO2nanolaminate, exhibits no signs of corrosion after a 1000 h ISO 9227 salt spray test and demonstrates a maximum surface hardness of 5.5 GPa. The same coating also suffers negligible damage in an atomic oxygen test, which is comparable to 1 year of exposure to space in low Earth orbit.

SummaryThis article presents results of an analysis of winter losses of honey bee colonies from 19 mainly European countries, most of which implemented the standardised 2013 COLOSS questionnaire. Generalised linear mixed effects models (GLMMs) were used to investigate the effects of several factors on the risk of colony loss, including different treatments for Varroa destructor, allowing for random effects of beekeeper and region. Both winter and summer treatments were considered, and the most common combinations of treatment and timing were used to define treatment factor levels. Overall and within country colony loss rates are presented. Significant factors in the model were found to be: percentage of young queens in the colonies before winter, extent of queen problems in summer, treatment of the varroa mite, and access by foraging honey bees to oilseed rape and maize. Spatial variation at the beekeeper level is shown across geographical regions using random effects from the fitted models, both before and after allowing for the effect of the significant terms in the model. This spatial variation is considerable.

In this paper, we present a distributed algorithm for the reconstruction of large-scale nonlinear networks. In particular, we focus on the identification from time-series data of the nonlinear functional forms and associated parameters of large-scale nonlinear networks. In the previous work, a nonlinear network reconstruction problem was formulated as a nonconvex optimisation problem based on the combination of a marginal likelihood maximisation procedure with sparsity inducing priors. In this paper, we derive an iterative reweighted lasso algorithm to solve the initial nonconvex optimisation problem based on the concave-convex procedure (CCCP). Moreover, by exploiting the structure of the objective function of this algorithm, a distributed algorithm is designed. To this end, we apply the alternating direction method of multipliers (ADMM) to decompose the original problem into several subproblems. To illustrate the effectiveness of the proposed methods, we use our approach to identify a network of interconnected Kuramoto oscillators with different network sizes (500~100,000 nodes).

During the diagnosis of three unrelated patients with severe hypertriglyceridemia, three APOA5mutations [p.(Ser232_Leu235)del, p.Leu253Pro, and p.Asp332ValfsX4] were found without evidence of concomitant LPL, APOC2, or GPIHBP1mutations. The molecular mechanisms by which APOA5mutations result in severe hypertriglyceridemia remain poorly understood, and the functional impairment/s induced by these specific mutations was not obvious. Therefore, we performed a thorough structural and functional analysis that included follow-up of patients and their closest relatives, measurement of apoA-V serum concentrations, and sequencing of the APOA5gene in 200 nonhyperlipidemic controls. Further, we cloned, overexpressed, and purified both wild-type and mutant apoA-V variants and characterized their capacity to activate LPL. The interactions of recombinant wild-type and mutated apoA-V variants with liposomes of different composition, heparin, LRP1, sortilin, and SorLA/LR11 were also analyzed. Finally, to explore the possible structural consequences of these mutations, we developed a three-dimensional model of full-length, lipid-free human apoA-V. A complex, wide array of impairments was found in each of the three mutants, suggesting that the specific residues affected are critical structural determinants for apoA-V function in lipoprotein metabolism and, therefore, that these APOA5mutations are a direct cause of hypertriglyceridemia.

In this paper an order reduction method for spatially distributed models is presented. Such systems may be modeled as two nodes interacting with each other through feedback. A model of one of the nodes reduced in such a way, that the closed loop performance is approximated. The method exploits a coprime factor description of the closed loop model and semidefinite programming. The method is related to controller reduction techniques and therefore is compared to those. Numerical examples show that using this algorithm the performance of the reduced order controller may be significantly improved.

Along the ribosome assembly pathway, various ribosomal RNA processing and modification reactions take place. Stem–loop 69 in the large subunit of Escherichia coli ribosomes plays a substantial role in ribosome functioning. It contains three highly conserved pseudouridines synthesized by pseudouridine synthase RluD. One of the pseudouridines is further methylated by RlmH. In this paper we show that RlmH has unique substrate specificity among rRNA modification enzymes. It preferentially methylates pseudouridine and less efficiently uridine. Furthermore, RlmH is the only known modification enzyme that is specific to 70S ribosomes. Kinetic parameters determined for RlmH are the following: The apparent KMfor substrate 70S ribosomes is 0.51 ± 0.06 µM, and for cofactor S-adenosyl-L-methionine 27 ± 3 µM; the kcatvalues are 4.95 ± 1.10 min–1and 6.4 ± 1.3 min–1, respectively. Knowledge of the substrate specificity and the kinetic parameters of RlmH made it possible to determine the kinetic parameters for RluD as well. The KMvalue for substrate 50S subunits is 0.98 ± 0.18 µM and the kcatvalue is 1.97 ± 0.46 min–1. RluD is the first rRNA pseudouridine synthase to be kinetically characterized. The determined rates of RluD- and RlmH-directed modifications of 23S rRNA are compatible with the rate of 50S assembly in vivo. The fact that RlmH requires 30S subunits demonstrates the dependence of 50S subunit maturation on the simultaneous presence of 30S subunits.

Background: While the integration of alcohol screening, treatment, and referral in primary care and other medical settings in the U.S. and worldwide has been recognized as a key health care priority, it is not routinely done. In spite of the high co‐occurrence and excess mortality associated with alcohol use disorders (AUDs) among individuals with tuberculosis (TB), there are no studies evaluating effectiveness of integrating alcohol care into routine treatment for this disorder.

We introduce a new design framework for implementing negative feedback regulation in synthetic biology, which we term ‘dichotomous feedback’. Our approach is different from current methods, in that it sequesters existing fluxes in the process to be controlled, and in this way takes advantage of the process’s architecture to design the control law. This signal sequestration mechanism appears in many natural biological systems and can potentially be easier to realize than ‘molecular sequestration’ and other comparison motifs that are nowadays common in biomolecular feedback control design. The loop is closed by linking the strength of signal sequestration to the process output. Our feedback regulation mechanism is motivated by two-component signalling systems, where a second response regulator could be competing with the natural response regulator thus sequestering kinase activity. Here, dichotomous feedback is established by increasing the concentration of the second response regulator as the level of the output of the natural process increases. Extensive analysis demonstrates how this type of feedback shapes the signal response, attenuates intrinsic noise while increasing robustness and reducing crosstalk.

In ribosomal RNA, modified nucleosides are found in functionally important regions, but their function is obscure. Stem-loop 69 of Escherichia coli 23S rRNA contains three modified nucleosides: pseudouridines at positions 1911 and 1917, and N3 methyl-pseudouridine (m(3)Psi) at position 1915. The gene for pseudouridine methyltransferase was previously not known. We identified E. coli protein YbeA as the methyltransferase methylating Psi1915 in 23S rRNA. The E. coli ybeA gene deletion strain lacks the N3 methylation at position 1915 of 23S rRNA as revealed by primer extension and nucleoside analysis by HPLC. Methylation at position 1915 is restored in the ybeA deletion strain when recombinant YbeA protein is expressed from a plasmid. In addition, we show that purified YbeA protein is able to methylate pseudouridine in vitro using 70S ribosomes but not 50S subunits from the ybeA deletion strain as substrate. Pseudouridine is the preferred substrate as revealed by the inability of YbeA to methylate uridine at position 1915. This shows that YbeA is acting at the final stage during ribosome assembly, probably during translation initiation. Hereby, we propose to rename the YbeA protein to RlmH according to uniform nomenclature of RNA methyltransferases. RlmH belongs to the SPOUT superfamily of methyltransferases. RlmH was found to be well conserved in bacteria, and the gene is present in plant and in several archaeal genomes. RlmH is the first pseudouridine specific methyltransferase identified so far and is likely to be the only one existing in bacteria, as m(3)Psi1915 is the only methylated pseudouridine in bacteria described to date.

The article discusses radiocarbon dates of 17 skeletons excavated from ten Stone Age burial sites in Estonia. The skeletons, dated by the AMS method in the frames of different research projects in recent years, are presented by burial sites together with detailed descriptions of the graves. The graves are compared with one another and main temporal differences and similarities are introduced. If the obtained results are different from the interpretations valid so far, the credibility of the dates is contemplated on.  On the basis of the obtained radiocarbon dates the Estonian Stone Age inhumation graves can be divided into four groups: the Early Neolithic Veibri II, Tamula VII and Kivi­saare IV, the end of the Early Neolithic–the beginning of the Middle Neolithic Tamula VIII and X, the Middle Neolithic Tamula I, III, XIX and Kudruküla and the Late Neolithic Ardu II, Sope II, Tika, Kunila II, Karlova and Naakamäe. The dates enable following changes in the burial customs during the Neolithic more exactly than before. In addition to the burials within settlement sites also separate burial sites have been established all through the Neolithic. Single burials dominate at that time and the deceased have been buried both in straight supine and flexed positions however, the composition and number of grave goods vary.   Resümee. On käsitletud kümnest Eesti kiviaja matmispaigast väljakaevatud 17 luustiku radiosüsiniku­dateeringuid. Viimastel aastatel erinevate uurimisprojektide raames kiirendi-mass-spektro­meetriga AMS dateeritud luustikud on esitatud muististe kaupa koos haudade detailse kirjeldusega. Haudu on omavahel võrreldud ja välja toodud olulisemad ajalised erinevused ja sarnasused. Juhul kui saadud tulemused erinevad senistest tõlgendustest, on vaetud vanuse­määrangute usaldusväärsuse üle. Saadud radiosüsinikudateeringute põhjal võib Eesti kiviaegsed maahaudkalmed jagada ajaliselt neljaks rühmaks: varaneoliitikum Veibri II, Tamula VII ja Kivisaare IV, varaneolii­tikumi lõppkeskneoliitikumi algus Tamula VIII ja X, keskneoliitikum Tamula I, III, XIX ja Kudruküla ning hilisneoliitikum Ardu II, Sope II, Tika, Kunila II, Karlova ja Naakamäe. Saadud dateeringud võimaldavad neoliitikumi jooksul matmiskombestikus toimunud muutusi senisest palju täpsemalt jälgida. Läbi neoliitikumi on lisaks elupaikadesse tehtud matustele rajatud ka eraldi paiknevaid kalmistuid. Valdavad on üksikmatused ja kogu perioodi jooksul on surnuid maetud nii selili-siruli- kui ka kägarasendis, varieerub aga hauapanuste kooslus ning hulk.

ResumenPresentamos, desde una perspectiva constructivista, una revisión crítica de las raíces y marco conceptual de la psicología cognitiva, especialmente la que se ha configurado en torno al mecanicismo abstracto. La caracterizamos en el marco de la dialéctica positivismo-pragmatismo, y no como síntesis de racionalismoy empirismo. Analizamos las paradojas y limitaciones computacionales, derivadas del dualismo, del realismo representacional, del prejuicio de la interiorización, y de la imposible reducción mecánica de las funciones orgánicas. Revisamos críticamente los conceptos de máquina, símbolo, representación y significado y desarrollamos una serie de sugerencias teóricas alternativas, en torno a una noción de función orgánica derivada de la tradición constructivista. Concluimos con unas consideraciones sobre el dominio académico del mentalismo.

Presentamos, desde una perspectiva constructivista, una revisión crítica de las raíces y marco conceptual de la psicología cognitiva, especialmente la que se ha configurado en torno al mecanicismo abstracto. La caracterizamos en el marco de la dialéctica positivismo-pragmatismo, y no como síntesis de racionalismoy empirismo. Analizamos las paradojas y limitaciones computacionales, derivadas del dualismo, del realismo representacional, del prejuicio de la interiorización, y de la imposible reducción mecánica de las funciones orgánicas. Revisamos críticamente los conceptos de máquina, símbolo, representación y significado y desarrollamos una serie de sugerencias teóricas alternativas, en torno a una noción de función orgánica derivada de la tradición constructivista. Concluimos con unas consideraciones sobre el dominio académico del mentalismo.

Abstract.:  Titanium oxide and zirconium oxide thin films deposited on silicon substrates were characterised using electron probe microanalysis (EPMA), Rutherford backscattering spectroscopy (RBS), time-of-flight elastic recoil detection analysis (TOF-ERDA) and scanning photoelectron microscopy (SPEM). The composition and mass thickness of the films were determined and the results of different methods compared. It was revealed that the synchrotron radiation used for SPEM studies caused considerable modification of zirconia films grown at low temperatures.

Apolipoprotein CII (apoCII) activates lipoprotein lipase (LPL). Seven residues, located on one face of a model α-helix spanning residues 59–75, are fully conserved in apoCII from ten different animal species. We have mutated these residues one by one. Substitution of Ala59by glycine, or Thr62and Gly65by alanine did not change the activation, indicating that these residues are outside the LPL-binding site. Replacement of Tyr63, Ile66, Asp69, or Gln70by alanine lowered the affinity for LPL and the catalytic activity of the LPL·apoCII complex. For each residue several additional replacements were made. Most mutants retained some activating ability, but replacement of Tyr63by phenylalanine or tryptophan and Gln70by glutamate caused almost complete loss of activity. All mutants bound to liposomes with similar affinity as wild-type apoCII, and they also bound with similar affinity to LPL in the absence of hydrolyzable lipids. However, the inactive mutants did not compete with wild-type apoCII in the activation assay. Therefore, we conclude that the productive apoCII·LPL interaction may be dependent on substrate molecules. In summary, our data demonstrate that residues 63, 66, 69, and 70 are of special importance for the function of apoCII, but no single amino acid residue is absolutely crucial.

Lipoprotein lipase (LPL) efficiently mediates the binding of lipoprotein particles to lipoprotein receptors and to proteoglycans at cell surfaces and in the extracellular matrix. It has been proposed that LPL increases the retention of atherogenic lipoproteins in the vessel wall and mediates the uptake of lipoproteins in cells, thereby promoting lipid accumulation and plaque formation. We investigated the interaction between LPL and low density lipoproteins (LDLs) with special reference to the protein-protein interaction between LPL and apolipoprotein B (apoB). Chemical modification of lysines and arginines in apoB or mutation of its main proteoglycan binding site did not abolish the interaction of LDL with LPL as shown by surface plasmon resonance (SPR) and by experiments with THP-I macrophages. Recombinant LDL with either apoB100 or apoB48 bound with similar affinity. In contrast, partial delipidation of LDL markedly decreased binding to LPL. In cell culture experiments, phosphatidylcholine-containing liposomes competed efficiently with LDL for binding to LPL. Each LDL particle bound several (up to 15) LPL dimers as determined by SPR and by experiments with THP-I macrophages. A recombinant NH2-terminal fragment of apoB (apoB17) bound with low affinity to LPL as shown by SPR, but this interaction was completely abolished by partial delipidation of apoB17. We conclude that the LPL-apoB interaction is not significant in bridging LDL to cell surfaces and matrix components; the main interaction is between LPL and the LDL lipids.

The C-terminal domain of lipoprotein lipase (LPL) is involved in several important interactions. To assess its contribution to the binding ability of full-length LPL we have determined kinetic constants using biosensor technique. The affinity of the C-terminal domain for heparin was about 500-fold lower than that of full-length LPL (Kd = 1.3 μM compared to 3.1 nM). Replacement of Lys403, Arg405 and Lys407 by Ala abolished the heparin affinity, whereas replacement of Arg420 and Lys422 had little effect. The C-terminal domain increased binding of chylomicrons and VLDL to immobilized heparin relatively well, but was less than 10% efficient in binding of LDL compared to full-length LPL. Deletion of residues 390–393 (WSDW) did not change the affinity to heparin and only slightly decreased the affinity to lipoproteins. We conclude that the C-terminal folding domain contributes only moderately to the heparin affinity of full-length LPL, whereas the domain appears important for tethering triglyceride-rich lipoproteins to heparin-bound LPL.

•Quantitative comparison of settlement systems with first order point process models.•Usable area by Corded Ware culture increased compared to hunter-fisher-gatherer.•Larger usable land made possible the migration of early agrarian society.•Overlap of suitable residential areas could have led to competition for space.•Spatial land use structure was more homogeneous for early agrarian population.•Differing model performance can be caused by social structure or land-use patterns.

The low density lipoprotein receptor-related protein (LRP) is a multifunctional endocytic cell-surface receptor that binds and internalizes a diverse array of ligands. The receptor contains four putative ligand-binding domains, generally referred to as clusters I, II, III, and IV. In this study, soluble recombinant receptor fragments, representing each of the four individual clusters, were used to map the binding sites of a set of structurally and functionally distinct ligands. Using surface plasmon resonance, we studied the binding of these fragments to methylamine-activated α2-macroglobulin, pro-urokinase-type plasminogen activator, tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1, t-PA·plasminogen activator inhibitor-1 complexes, lipoprotein lipase, apolipoprotein E, tissue factor pathway inhibitor, lactoferrin, the light chain of blood coagulation factor VIII, and the intracellular chaperone receptor-associated protein (RAP). No binding of the cluster I fragment to any of the tested ligands was observed. The cluster III fragment only bound to the anti-LRP monoclonal antibody α2MRα3 and weakly to RAP. Except for t-PA, we found that each of the ligands tested binds both to cluster II and to cluster IV. The affinity rate constants of ligand binding to clusters II and IV and to LRP were measured, showing that clusters II and IV display only minor differences in ligand-binding kinetics. Furthermore, we demonstrate that the subdomains C3–C7 of cluster II are essential for binding of ligands and that this segment partially overlaps with a RAP-binding site on cluster II. Finally, we show that one RAP molecule can bind to different clusters simultaneously, supporting a model in which RAP binding to LRP induces a conformational change in the receptor that is incompatible with ligand binding.

Abstract: The aim of this study was to investigate the influence of restriction of movement on the functional characteristics and myosin heavy chain composition of m. vastus medialis. The subjects of this study were 13 arthroscopically treated patients with meniscus lesions (both men and women, mean age 28 years). All measurements were performed and biopsies were taken bilaterally before and 6 months after knee arthroscopy. Thigh girth was measured to determine the degree of atrophy. A tendency towards decreased thigh girth in the injured leg was noted. As an estimate of functional characteristics, maximum voluntary contraction (MVC) was measured. The MVC of the injured limb was lower than that of the non-injured limb (mean values 548.2 � 54.1 and 705.4 � 48.2 N respectively; P < 0.05). The myosin heavy chain (MHC) composition was determined electrophoretically. The proportion of MHC I isoform decreased from 59.35% to 47.97% (P < 0.05).

The aim of this study was to investigate the influence of restriction of movement on the functional characteristics and myosin heavy chain composition of m. vastus medialis. The subjects of this study were 13 arthroscopically treated patients with meniscus lesions (both men and women, mean age 28 years). All measurements were performed and biopsies were taken bilaterally before and 6 months after knee arthroscopy. Thigh girth was measured to determine the degree of atrophy. A tendency towards decreased thigh girth in the injured leg was noted. As an estimate of functional characteristics, maximum voluntary contraction (MVC) was measured. The MVC of the injured limb was lower than that of the non-injured limb (mean values 548.2 ± 54.1 and 705.4 ± 48.2 N respectively; P< 0.05). The myosin heavy chain (MHC) composition was determined electrophoretically. The proportion of MHC I isoform decreased from 59.35% to 47.97% (P< 0.05).

The ability of mutant 23 S ribosomal RNA to form particles with proteins of the large ribosomal subunitin vivowas studied. A series of overlapping deletions covering the entire 23 S rRNA, were constructed in the plasmid copy of anE. coli23 S rRNA gene. The mutant genes were expressedin vivousing an inducibletacpromoter. Mutant species of 23 S rRNA, containing deletions between positions 40 and 2773, were incorporated into stable ribonucleoprotein particles. In contrast, if one end of the 23 S rRNA was deleted, the mutant rRNA was unstable and did not form ribosomal particles. Protein composition of the mutant particles was specific; the presence of the primary rRNA-binding proteins corresponded to their known binding sites. Furthermore, several previously unknown ribosomal protein binding sites in 23 S rRNA were identified. Implications of the results on ribosome assembly are discussed.

One-stage repair of hypospadias is currently fashionable and is undoubtedly attractive in concept but the methods that are presently available all have inherent limitations and drawbacks. The author presents a two-stage method which offers a unique combination of versatility, reliability and refinement, and can be used for almost any hypospadias deformity, be it primary repair in a child or salvage surgery in an adult. A personal series of 600 cases is analysed.

Single functional human CuZnSOD gene encodes two species of mRNA differing in size by 200 nucleotides in the 3′‐untranslated region (UTR). We studied the expression of the CuZnSOD cDNA with different 3′‐ and 5′‐UTR. Deletion in the 5′‐end does not affect the expression of the enzyme, however, deletion in the 3′‐UTR decreases the level of expression of CuZnSOD. The plasmids containing the long CuZnSOD cDNA with all polyadenylation signal sequences utilize primarily the last polyadenylation site and give a long mRNA, which produces three times more enzyme than the short mRNA lacking the last polyadenylation site and the AU‐rich region.

Lipoprotein lipase (LPL) is present in cells involved in development of atherosclerosis (endothelial cells, smooth muscle cells, and macrophages). A direct involvement of LPL in atherogenesis has been suggested. Previously we used the surface plasmon resonance technique to study the interaction of lipoproteins with surfaces covered by heparan sulfate proteoglycans (HSPG) and LPL [A. Lookeneet al.(1997)Biochemistry36, 5267–5275]. The binding was much increased by the presence of LPL. Here we demonstrate that mild oxidation of low-density-lipoprotein (LDL) and very-low-density lipoprotein (VLDL)in vitroincreases their binding to surfaces covered by HSPG and LPL, while extensive oxidation decreases it. Similar results were obtained with a lipid emulsion (Intralipid), indicating that oxidation-induced changes of the lipid part could explain the effects. LPL increased binding and uptake of the mildly oxidized (compared to nonoxidized) LDL by THP-I monocyte-derived macrophages. Our studies indicate that LPL has the highest affinity for mildly oxidized LDL and support its involvement in development of atherosclerosis.