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A series of abrupt climate events linked to circum-North Atlantic meltwater forcing have been recognised in Holocene paleoclimate data. To address the paucity of proxy records able to characterise robustly the regional impacts of these events, we retrieved a sub-centennial resolution, well-dated core sequence from Lake Kuutsjärvi, northeast Finland. By analysing a range of paleo-environmental proxies (pollen, plant sedimentary ancient DNA, plant macrofossils, conifer stomata, and non-pollen palynomorphs), and supported with proxy-based paleotemperature and moisture reconstructions, we unravel a well-defined sequence of vegetation and climate dynamics over the early-to-middle Holocene. The birch-dominated pioneer vegetation stage was intersected by two transient tree-cover decrease events at 10.4 and 10.1 thousand years ago (ka), likely representing a two-pronged signal of the 10.3 ka climate event. Our data also show a clear signal of the 8.2 ka climate event, previously not well recorded in the European Arctic, with a collapse of the pine-birch forest and replacement by juniper developing in tight synchrony with Greenland isotopic proxies over 8.4–8.0 ka. Supported by climate modelling, severe winter cooling rather than summer might have been driving vegetation disruptions in the early Holocene. The Kuutsjärvi data indicate an early arrival of Norway spruce (Picea abies) by 9.2 ka (pollen, DNA, and stoma finds), as well as the first evidence for Holocene presence of larch (Larix) in Finland, with pollen finds dating to 9.6–5.9 ka. • A high-resolution multiproxy Holocene lake core sequence retrieved from N Finland. • Arrival of spruce by 9.2 ka indicated by pollen, sedimentary DNA, and stoma finds. • First evidence of Holocene larch in Finland,with pollen finds dated to 9.6–5.9 ka. • Tree-cover decreases at 10.4 and 10.1 ka, possibly linked to 10.3k climate event. • Signal of 8.2k climate event, with forest collapse sychronous with Greenland data. [ABSTRACT FROM AUTHOR]

The Last Interglacial (LIG; 130-115 ka) is an important test bed for climate science as an instance of significantly warmer than preindustrial global temperatures. However, LIG climate patterns remain poorly resolved, especially for winter, affected by a suite of strong feedbacks such as changes in sea-ice cover in the high latitudes. We present a synthesis of winter temperature and precipitation proxy data from the Atlantic seaboard of Europe, spanning from southern Iberia to the Arctic. Our data reveal distinct, opposite latitudinal climate trends, including warming winters seen in the European Arctic while cooling and drying occurred in southwest Europe over the LIG. Climate model simulations for 130 and 120 ka suggest these contrasting climate patterns were affected by a shift toward an atmospheric circulation regime with an enhanced meridional pressure gradient and strengthened midlatitude westerlies, leading to a strong reduction in precipitation across southern Europe. [ABSTRACT FROM AUTHOR]

Three different thermal carbonization processes of porous silicon (PS) surface by acetylene occurring between 400 and 950 °C were observed by in situ measurements. The peak temperature of oxidation shifts from 300 to 600 °C and the activation energy from 130 to 500 kJ/mole in the samples treated at 900 °C compared to untreated PS. Using Fourier transform infrared spectroscopy (FTIR), the bonding configurations associated with the temperature dependent processes were found. In the samples treated at or below 600 °C, traces of C–H[sub x] bonds were clearly seen, but above 600 °C the FTIR spectra started resemble those of the SiC. The graphitization process was found to take place on the surface of PS samples treated above 800 °C. By changing the time between the C[sub 2]H[sub 2] flush and thermal treatment, the graphitization can be controlled and even avoided. The weight increase was observed to be nearly proportional to the reduction of the surface area while the decrease in the surface area due to the thermal carbonization was found to be small. The origin of this phenomenon and the effects of other preparation parameters have been discussed. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents information on a study which used an isothermal microcalorimetric method to analyze photoinduced effects in porous silicon. Impact of aging to porous silicon; Methodology; Theory of the beam of light; Results and discussion; Conclusions.

We discuss a proboscidean bone fragment discovered in southern Finland, including the morphological analysis of the bone, as well as pollen and diatom analyses from sediment contained in the marrow cavity. Preliminary analysis of the bone suggested petrification and thus an apparently old age, while the microfossil assemblages include numerous unequivocally pre-Quaternary pollen, spore, and diatom types. A Miocene age for the bone is determined based on the presence of the diatom genus Alveolophora , indicating a minimum age of 5 Ma, and based on the earliest appearance of proboscideans outside Africa, setting a maximum age of 19 Ma. Based on morphology, the bone is determined as a partial humerus of the left foreleg of a large proboscidean. The bone is tentatively assigned to cf. Deinotherium sp., which is consistent with the diatom-based minimum age. The pollen assemblage is rich in spores of shoreline pteridophytes, while the diatom assemblage is also consistent with a shoreline freshwater environment, suggesting that the bone was deposited post-mortem near the shore of a lake or a stream. Miocene sediments do not currently exist in southern Finland or in the near vicinity. This implies that the bone has been transported over a considerable distance. Due to the discovery of the bone in early-Holocene Baltic Sea clay, the final transport phase and deposition must have taken place via iceberg rafting. This was likely preceded by one or more phases of glacial and/or glacio-fluvial transport. While we are unable to conclusive ascertain the region of origin, the alkaline composition of the contained sediment and diatoms point towards the Russian Plain region in the east. This specimen represents the oldest mammalian bone discovered in Finland and the northernmost discovery of a Miocene proboscidean bone in Europe. [ABSTRACT FROM AUTHOR]

We examine the ability of four different regression-tree ensemble techniques (bagging, random forest, rotation forest and boosted tree) in calibration of aquatic microfossil proxies. The methods are tested with six chironomid and diatom datasets, using a variety of cross-validation schemes. We find random forest, rotation forest and the boosted tree to have a similar performance, while bagging performs less well and in several cases has trouble producing continuous predictions. In comparison with commonly used parametric transfer-function approaches (PLS, WA, WA-PLS), we find that in some cases tree-ensemble methods outperform the best-performing transfer-function technique, especially with large datasets characterized by complex taxon responses and abundant noise. However, parametric transfer functions remain competitive with datasets characterized by low number of samples or linear taxon responses. We present an implementation of the rotation forest algorithm in R. [ABSTRACT FROM AUTHOR]

The degree of climate instability on the continent during the warmer-than-present Eemian Interglacial (around ca. 123 kyr ago) remains unsolved. Recently published high-resolution proxy data from the North Atlantic Ocean suggest that the Eemian was punctuated by abrupt events with reductions in North Atlantic Deep Water formation accompanied by sea-surface temperature cooling. Here we present multi-proxy data at an unprecedented resolution that reveals a major cooling event intersecting peak Eemian warmth on the North European continent. Two independent temperature reconstructions based on terrestrial plants and chironomids indicate a summer cooling of the order of 2–4 °C. The cooling event started abruptly, had a step-wise recovery, and lasted 500–1000 yr. Our results demonstrate that the common view of relatively stable interglacial climate conditions on the continent should be revised, and that perturbations in the North Atlantic oceanic circulation under warmer-than-present interglacial conditions may also lead to abrupt and dramatic changes on the adjacent continent. [ABSTRACT FROM AUTHOR]

Abstract: We test and analyse a new calibration method, boosted regression trees (BRTs) in palaeoclimatic reconstructions based on fossil pollen assemblages. We apply BRTs to multiple Holocene and Lateglacial pollen sequences from northern Europe, and compare their performance with two commonly-used calibration methods: weighted averaging regression (WA) and the modern-analogue technique (MAT). Using these calibration methods and fossil pollen data, we present synthetic reconstructions of Holocene summer temperature, winter temperature, and water balance changes in northern Europe. Highly consistent trends are found for summer temperature, with a distinct Holocene thermal maximum at ca 8000–4000 cal. a BP, with a mean T jja anomaly of ca +0.7 °C at 6 ka compared to 0.5 ka. We were unable to reconstruct reliably winter temperature or water balance, due to the confounding effects of summer temperature and the great between-reconstruction variability. We find BRTs to be a promising tool for quantitative reconstructions from palaeoenvironmental proxy data. BRTs show good performance in cross-validations compared with WA and MAT, can model a variety of taxon response types, find relevant predictors and incorporate interactions between predictors, and show some robustness with non-analogue fossil assemblages. [Copyright &y& Elsevier]

Quantitative palaeoclimatic reconstructions based on biological fossils are a major source of information on long-term climatic variability. Such reconstructions typically use some kind of a modern calibration data set describing the variation of the studied biological group in present-day climate space. Here, we explore the effect of calibration data set selection on palaeoclimatic reconstructions, by creating alternate calibration data sets via stratified random sampling to reconstruct mean July temperature (Tjul) for four fossil pollen sequences from northern Europe. We show that palaeoclimatic reconstructions using methods based on taxon-response models can be highly sensitive to the calibration data set used. In particular, the absolute reconstructed temperatures show great sensitivity to calibration data selection, which suggests that the absolute values of palaeoclimatic reconstructions may not be robust. By contrast, we find the relative shapes of the reconstructed curves to be more robust to calibration data selection because taxa tend to occupy similar relative locations along the sampled gradient regardless of calibration data set location. Based on this robustness of relative palaeoclimate curves, we suggest a debiasing procedure in which palaeoclimate values are estimated by fixing the relative curve with the modern observed value, thus correcting biases resulting from calibration data selection. [ABSTRACT FROM PUBLISHER]

S alonen J, H yvönen T, K aseva J & J alli H (2012). Impact of changed cropping practices on weed occurrence in spring cereals in Finland - a comparison of surveys in 1997-1999 and 2007-2009. Weed Research. Summary During recent decades, arable cropping has been intensified to increase production, but has also been constrained by agri-environment schemes. Weed populations respond to such changes, thus indicating trends in cropping practices. In Finland, repeated monitoring of the weed flora aims to record and understand the response of weed populations to changing cultural conditions. Two recent surveys of the weed flora in Finnish spring cereal fields, conducted in 1997-1999 and 2007-2009, were evaluated to assess the effect of known changes in tillage practices and herbicide use on weed occurrence. The same 382 fields were assessed during both decades. In conventional cropping, the total abundance of weeds has remained at about the same level as recorded in the late 1990s. Overwintering weed species like Galium spurium, Lamium spp., Lapsana communis and Poa annua have become more frequent, indicating a trend towards reduced primary tillage. Increased use of glyphosate has in turn led to a decline in Elymus repens, particularly in non-ploughed fields. Substantially increased total biomass of weeds was associated with organic cropping, due to lack of direct weed control methods and inadequate crop competition. The opposite trend was apparent in the fields, which had returned from organic farming back to conventional cropping. The results suggest that more decisive IPM strategies are required, both in organic cropping to stop the increasing weed biomass and in conventional cropping to reduce current reliance on herbicides. [ABSTRACT FROM AUTHOR]

Abstract: We present a new pollen–climate calibration data-set from northern Europe consisting of 583 modern pollen samples and high-resolution, GIS-based modern climate data. The pollen data are characterised by high taxonomic resolution (167 taxa) and homogenous taphonomy (all samples are from small-to-medium-sized lakes). To assess the potential of this calibration set for the reconstruction of different climatic parameters, we use novel regression tree methods to analyse the effect on pollen composition and variability of four parameters: summer temperature, winter temperature, water balance, and continentality index. We use multivariate regression trees to analyse the variation in pollen assemblages in modern climate space, while boosted regression trees are used to analyse the relative influence of different climatic parameters on each taxon. We find taxon responses to be relatively individualistic. While most taxa (65%) are most responsive to summer temperature, other parameters are either primary determinants or significant secondary determinants for many taxa. At the assemblage level, significant variation is found in assemblages from similar summer temperature regimes, with distinct clusters of assemblages also identified along the continentality gradient. As a multivariate method, we consider boosted regression trees highly effective in describing and modelling modern climate–taxon relationships. [Copyright &y& Elsevier]

We compare a Bayesian modelling-based technique with weighted averaging (WA) and weighted averaging-partial least squares (WA-PLS) regression in pollen-based summer temperature transfer function calibration. We test the methods using a new, 113-sample calibration set from Estonia, Lithuania and European Russia, and a Holocene fossil pollen sequence from Lake Kharinei, a previously studied lake in northeast European Russia. We find WA-PLS to outperform WA, probably because of smaller edge-effect biases in the ends of the calibration set gradient. The Bayesian-based calibration models show further improved performance compared with WA-PLS in leave-one-out cross-validation, while additional h-block cross-validation shows the Bayesian method to be little affected by spatial autocorrelation. Comparison with independent climate proxies reveals, however, some clear biases in the Bayesian palaeotemperature reconstructions, likely reflecting in part some specific limitations of our calibration set. As the selected prior parameters can significantly affect both Bayesian cross-validation performance and reconstructions, there is a clear need to further test the Bayesian method in different geographic contexts and over different timescales, with special attention given to the selection of the most realistic priors in each situation. In general, our finding that statistically well-performing transfer functions may produce clearly differing palaeotemperature reconstructions urges caution in transfer function-based inferences. We additionally test a spatially restricted, 58-sample subset of the full 113-sample calibration set. We find some reduced biases with the smaller set, likely because of complex, partially bimodal responses of several taxa along the longer temperature gradient, ill-suited for calibration methods assuming unimodal responses to climate. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the Holocene climate and treeline dynamics in the European Russian Arctic, we analysed sediment pollen, conifer stomata, and plant macrofossils from Lake Kharinei, a tundra lake near the treeline in the Pechora area. We present quantitative summer temperature reconstructions from Lake Kharinei and Lake Tumbulovaty, a previously studied lake in the same region, using a pollen–climate transfer function based on a new calibration set from northern European Russia. Our records suggest that the early-Holocene summer temperatures from 11,500calyr BP onwards were already slightly higher than at present, followed by a stable Holocene Thermal Maximum (HTM) at 8000–3500calyr BP when summer temperatures in the tundra were ca. 3°C above present-day values. A Picea forest surrounded Lake Kharinei during the HTM, reaching 150km north of the present taiga limit. The HTM ended with a temperature drop at 3500–2500calyr BP associated with permafrost initiation in the region. Mixed spruce forest began to disappear around Lake Kharinei at ca. 3500calyr BP, with the last tree macrofossils recorded at ca. 2500calyr BP, suggesting that the present wide tundra zone in the Pechora region formed during the last ca. 3500yr. [Copyright &y& Elsevier]

The feasibility of four mesoporous materials composed of biocompatible Si (TCPSi) or SiO2 (MCM-41, SBA-15, and TUD-1) were evaluated for oral drug delivery applications. The main focus was to study the effect of the materials different pore systems (unidirectional/2D/3D) and their pore diameters, pore size distributions, pore volumes on the maximal drug load capacity, and release profiles of a loaded active pharmaceutical ingredient. Ibuprofen was used as the model drug. The total pore volume of the mesoporous solid was the main factor limiting the maximum drug load capacity, with SBA-15 reaching a very high drug load of 1:1 in weight due to its high pore volume. Dissolution experiments were performed in HBSS buffers of pH 5.5, 6.8, and 7.4 to mimic the conditions in the small intestine. At pH 5.5 the dissolution rate of ibuprofen released from the mesoporous carriers was significantly faster compared with the standard bulk ibuprofen (86-63% versus 25% released at 45 min), with the fastest release observed from the 3D pore network of TUD-1 carrier. The utilization of mesoporous carriers diminished the pH dependency of ibuprofen dissolution (pKa = 4.42), providing an interesting prospect for the formulation of poorly soluble drug compounds. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the efficacy and safety of caspofungin in patients treated in Finland during the period 2001–2004. The medical records of 78 adult patients treated with caspofungin in five major hospitals were reviewed retrospectively. Fifty-nine (76%) patients had proven invasive fungal infection, of whom 22 (28%) had aspergillosis and 37 (47%) had candidiasis. Nineteen (24%) patients were treated empirically; only 13 (17%) patients received caspofungin as primary therapy. A favourable response was achieved in 52 (67%) patients. The response rate was 78% in patients with candidiasis, and 50% in patients with aspergillosis. At the end of the study period, 40 (51%) patients remained alive; of the 38 deaths, nine (24%) were caused by fungal infection. The response rates were lower, although not significantly, for patients with high (>20) vs. low (≤20) Acute Physiology and Chronic Health Evaluation (APACHE II) scores (response rate 50% vs. 68%, p 0.48, respectively), and were also lower in patients with long-term (>20 days) vs. shorter duration (≤20 days) neutropenia (55% vs. 73%, p 0.32, respectively), and in those with an underlying haematological malignancy vs. patients with other diseases (59% vs. 73%, p 0.2, respectively). In five (6%) patients, caspofungin therapy was discontinued prematurely because of adverse drug reactions (ADRs) (elevated liver enzyme values in three patients, neuropathic pain in one, and skin rash in one). Serious ADRs occurred in two (3%) patients (severe hepatic insufficiency with consequent death, and eosinophilia with elevated alkaline phosphatase levels), and laboratory abnormalities, mostly mild and reversible, in 24 (31%) patients. In this unselected patient population, caspofungin was safe, well-tolerated, and had an efficacy comparable to that in previous reports from prospective trials. [ABSTRACT FROM AUTHOR]

Abstract: For the first time the feasibility of siliceous mesoporous material TUD-1 (Technische Universiteit Delft) for drug delivery was studied. Model drug, ibuprofen, was adsorbed into TUD-1 mesopores via a soaking procedure. Characterizations with nitrogen adsorption, XRD, TG, HPLC and DSC demonstrated the successful inclusion of ibuprofen into TUD-1 host. The amount of ibuprofen adsorbed into the nanoreservoir of TUD-1 material was higher than reported for other mesoporous silica drug carriers (drug/carrier 49.5wt.%). Drug release studies in vitro (HBSS buffer pH 5.5) demonstrated a fast and unrestricted liberation of ibuprofen, with 96% released at 210min of the dissolution assay. The drug dissolution profile of TUD-1 material with the random, foam-like three-dimensional mesopore network and high accessibility to the dissolution medium was found to be much faster (kinetic constant k =10.7) and more diffusion based (release constant n =0.64) compared to a mesoporous MCM-41 material with smaller, unidirectional mesopore channels (k =4.7, n =0.71). Also, the mesoporous carriers were found to significantly increase the dissolution rate of ibuprofen, when compared to the pure crystalline form of the drug (k =0.6, n =0.96). TUD-1 was constituted as a potential drug delivery device with fast release property, with prospective applications in the formulation of poorly soluble drug compounds. [Copyright &y& Elsevier]

Abstract: A simple humidity sensor based on thermally carbonized porous silicon has been used to detect low moisture contents in gaseous atmosphere. Thermal carbonization of porous silicon changes the surface to hydrophilic and improves the sensitivity and the stability of the sensor. The capacitive sensitivity (C/C 0 −1) over 6% in a range of 0–1RH% was obtained. The resolutions for capacitive and resistive measurements were found to be 0.45 and 0.35ppm, respectively. The resolution was limited by noise level and with a simple data averaging it was improved down to 0.20ppm. The response time was observed to be good and it varied from 0.5 to 2.6min. [Copyright &y& Elsevier]

Abstract: Mesoporous silicon (PSi) microparticles were produced using thermal carbonization (TCPSi) or thermal oxidation (TOPSi) to obtain surfaces suitable for oral drug administration applications. The loading of five model drugs (antipyrine, ibuprofen, griseofulvin, ranitidine and furosemide) into the microparticles and their subsequent release behaviour were studied. Loading of drugs into TCPSi and TOPSi microparticles showed, that in addition to effects regarding the stability of the particles in the presence of aqueous or organic solvents, surface properties will affect compound affinity towards the particle. In addition to the surface properties, the chemical nature of the drug and the loading solution seems to be critical to the loading process. This was reflected in the obtained loading efficiencies, which varied between 9% and 45% with TCPSi particles. The release rate of a loaded drug from TCPSi microparticles was found to depend on the characteristic dissolution behaviour of the drug substance. When the dissolution rate of the free/unloaded drug was high, the microparticles caused a delayed release. However, with poorly dissolving drugs, the loading into the mesoporous microparticles clearly improved dissolution. In addition, pH dependency of the dissolution was reduced when the drug substance was loaded into the microparticles. [Copyright &y& Elsevier]

The complement system is regarded as an important component of the innate defence system against invading bacteria. However, synergistic actions between the complement and the other components of innate immunity are incompletely known. Human group IIA phospholipase A2 (hGIIA PLA2) is an effective antibacterial enzyme in serum of patients with severe bacterial infections. Our aim was to investigate the significance of complement and hGIIA PLA2 in acute phase serum. Serum samples were collected from patients with acute bacterial infections and from healthy control subjects. We prepared hGIIA PLA2-depleted serum by immunoadsorption and inhibited the activity of complement by a specific inhibitor, compstatin. The bactericidal effects of treated and untreated serum were compared by incubating Staphylococcus aureus and Listeria monocytogenes in the presence of serum. Acute phase serum effectively killed S. aureus and L. monocytogenes, and depletion of hGIIA PLA2 significantly reduced the antibacterial effect. Complement had a weak bactericidal effect against L. monocytogenes. We conclude that hGIIA PLA2 is the major antibacterial factor in human acute phase serum against the gram-positive bacteria S. aureus and L. monocytogenes, exceeding complement in efficiency. [ABSTRACT FROM AUTHOR]

The temperature dependence of the electrical conductivity in thermally carbonized porous silicon has been studied. The temperature dependence of conductivity is dependent on the treatment temperature and on the thickness of the porous layer. Due to the treatment, the resistance is 10-5 times lower in samples thermally carbonized at 850 °C than in the as-anodized sample with the same thickness. The resistance–temperature characteristic of the thermally carbonized PSi was found to be well described by a thermistor equation and the temperature sensitivity was found to be good (5%/K at 25 °C). [Copyright &y& Elsevier]

Jantunen E, Salonen J, Juvonen E, Koivunen E, Siitonen T, Lehtinen T, Kuittinen O, Leppä S, Anttila V-J, Itälä M, Wiklund T, Remes K, Nousiainen T. Invasive fungal infections in autologous stem cell transplant recipients: a nation-wide study of 1188 transplanted patients. Eur J Haematol 2004: 73: 174–178. © Blackwell Munksgaard 2004. Based on small single-centre series, the risk of invasive fungal infections (IFI) has been considered small in autologous stem cell transplant (ASCT) recipients. Purpose: To analyse epidemiological and clinical features of (IFI) among ASCT recipients in Finland 1990–2001. Patients: During the study period, 1188 adult patients received high-dose therapy supported by ASCT in six centres. Altogether, 1112 patients (94%) received blood progenitor cells. The graft was CD34+ selected in 261 patients (22%). The major diagnostic groups were non-Hodgkin's lymphoma ( n = 417), multiple myeloma ( n = 395), breast cancer ( n = 132) and Hodgkin's lymphoma ( n = 53). Results: Eighteen patients (1.5%) with IFI were identified. The incidence of proven or probable invasive aspergillosis was 0.8%, followed by candidaemia with an incidence of 0.3%. The median time to the diagnosis of IFI was 35 d (6–162) from the progenitor cell infusion. In fourteen patients (78%) IFI was diagnosed during lifetime and they were treated with antifungal therapy for a median of 50 d. Nine patients (64%) were cured. Conclusions: IFI appears to be a rare event after ASCT and Aspergillus infections seem to be predominant. These epidemiological features have an impact in planning prophylactic and empirical antifungal strategies in ASCT recipients. [ABSTRACT FROM AUTHOR]

A feasible route to produce hydrocarbon termination to the porous silicon (PSi) surface has been introduced using thermal decomposition of acetylene molecules. Treatment temperatures lower than 600 °C enable the use of continuous acetylene flushing during the treatment without problems arising from the graphitization of acetylene. The continuous acetylene flushing was found to significantly improve the quality and efficiency of the treatment. The decomposition process starts at low temperatures and appears to consist of three different parts as a function of temperature. It was also found that the treatment time has some effects on the treatment efficiency. The hydrocarbon terminated PSi surface was found to be hydrophobic, when the treatment temperature was below 680 °C. Due to the hydrogen desorption, the surface quickly changes to hydrophilic above 700 °C. Thermal oxidation studies of the treated surfaces show improvements in the stability against oxidation and the hydrocarbon termination was found to be very stable even in aqueous KOH environment. [Copyright &y& Elsevier]

Reports on the determination of the thickness of an oxide layer at the p+-type porous silicon interface as a function of oxidation time, by using a small-angle X-ray scattering. Storage of porous silicon samples in various temperatures to achieve oxidation; Observation of the negative derivations from Porod's law from the scattering curves of oxidized samples.

Abstract. Salonen JT, Nyyssönen K, Salonen R, Lakka H-M, Kaikkonen J, Porkkala-Sarataho E, Voutilainen S, Lakka TA, Rissanen T, Leskinen L, tuomainen T-P, Valkonen V-P, Ristonmaa U (University of Kuopio, Finland), Poulsen HE (University of Copenhagen, Copenhagen, Denmark). Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) study: a randomized trial of the effect of vitamins E and C on 3-year progression of carotid atherosclerosis. J Intern Med 2000; 248: 377–386. Objectives. To study the efficacy of vitamin E and C supplementation on the progression of carotid atherosclerosis, hypothesizing an enhanced preventive effect in men and in smokers and synergism between vitamins. Design and subjects. Double-masked two-by-two factorial trial, randomization in four strata (by gender and smoking status) to receive twice daily either 91 mg (136 IU) of d-α-tocopherol, 250 mg of slow-release vitamin C, a combination of these or placebo for three years. A randomized sample of 520 smoking and nonsmoking men and postmenopausal women aged 45–69 years with serum cholesterol ≥ 5.0 mmol L–1 were studied. Setting. The population of the city of Kuopio in Eastern Finland. Intervention. Twice daily either a special formulation of 91 mg of d-α-tocopherol, 250 mg of slow-release vitamin C, a combination of these (CellaVie®) or placebo for three years. Measurements. Atherosclerotic progression, defined as the linear regression slope of ultrasonographically assessed common carotid artery mean intima–media thickness (IMT), was calculated over semi-annual assessments. Results. The average increase of the mean IMT was 0.020 mm year–1 amongst men randomized to placebo and 0.018 mm year–1 in vitamin E, 0.017 mm year–1 in vitamin C and 0.011 mm year–1 in the vitamin combination group (P = 0.008 for E + C vs. placebo). The respective means in women were 0.016, 0.015, 0.017 and 0.016 mm year–1. The proportion of men with progression was reduced by 74% (95% CI 36–89%, P = 0.003) by supplementation with the formulation containing both vitamins, as compared with placebo. Conclusions. Our study shows that a combined supplementation with reasonable doses of both vitamin E and slow-release vitamin C can retard the progression of common carotid atherosclerosis in men. This may imply benefits with regard to other atherosclerosis-based events. [ABSTRACT FROM AUTHOR]

We have used a new, commercial enzyme-linked immunosorbent assay (ELISA, Platelia Aspergillus) to detect Aspergillus antigen in serum, urine and bronchoalveolar lavage (BAL) samples of 105 haematological patients who received empirical amphotericin B treatment for suspected fungal infection. 14% (60/419) of serum and 5% (18/373) of urine samples were positive. Ten-fold concentration of urine increased the number of positive samples to 31 (8%). The antigen was detected in 5 of 20 BAL samples, but fungal culture was negative in all of them. 22 patients had positive antigen test. Serum was positive in 17, urine in 7 and concentrated urine in 12 patients. Six patients had confirmed invasive aspergillosis. In all these patients, antigen was detected in serum, but urine was positive in only 2 patients. Patients whose antigen test turned negative during the amphotericin B treatment had significantly lower mortality than patients with persistently positive antigen test (2/10 vs. 8/8, p = 0.002). We conclude that Aspergillus galactomannan can be detected by ELISA in serum, urine and BAL samples of haematological patients, but the higher sensitivity of serum testing makes it preferable for screening. Disappearance of the antigen during antifungal therapy seems to correlate with good, and persistence with poor, clinical outcome. [ABSTRACT FROM AUTHOR]

The birefringence of light in freely suspended samples of porous silicon is observed and investigated. The effect is interpreted as "shape birefringence," i.e., the effect caused by the structure of a material consisting of anisotropic formations with sizes less than the wavelength of the light and with a predominant orientation. It is checked experimentally that the samples do not possess optical activity or optical anisotropy in the plane of the porous-silicon film. It is determined that the effect is observed for polarization of incident light that rules out the possibility of observing birefringence in a uniform optical medium, and it is not observed in the conventional experimental geometry. Qualitative explanations are given for the anomalous character of the observed defect. [ABSTRACT FROM AUTHOR]

Presents a study which investigated the photoluminescence quenching of porous silicon in different atmospheres and in vacuum. Experimental procedures; Results and discussion; Conclusion.

Abstract: Nanostructured silicon interference filters have been thermally carbonized by acetylene decomposition at different temperatures in order to passivate their high internal surface area. Stability has been studied by periodically measuring the optical spectrum of treated and untreated porous silicon filters stored in oxidizing environments. Experimental results show that thermal carbonization stabilizes the structures against oxidation, since treated samples show no significant shift of their optical spectra after storage in either ambient air or ethanol for up to two months. Moreover, the thermal carbonization process has no significant effect on the optical performance of the filters. Results show that thermal carbonization by acetylene decomposition provides an effective way to produce chemically stable porous silicon optical devices for biological and chemical sensing. [Copyright &y& Elsevier]

We test several quantitative algorithms as palaeoclimate reconstruction tools for North American and European fossil pollen data, using both classical methods and newer machine-learning approaches based on regression tree ensembles and artificial neural networks. We focus on the reconstruction of secondary climate variables (here, January temperature and annual water balance), as their comparatively small ecological influence compared to the primary variable (July temperature) presents special challenges to palaeo-reconstructions. We test the pollen–climate models using a novel and comprehensive cross-validation approach, running a series of h-block cross-validations using h values of 100–1500 km. Our study illustrates major benefits of this variable h-block cross-validation scheme, as the effect of spatial autocorrelation is minimized, while the cross-validations with increasing h values can reveal instabilities in the calibration model and approximate challenges faced in palaeo-reconstructions with poor modern analogues. We achieve well-performing calibration models for both primary and secondary climate variables, with boosted regression trees providing the overall most robust performance, while the palaeoclimate reconstructions from fossil datasets show major independent features for the primary and secondary variables. Our results suggest that with careful variable selection and consideration of ecological processes, robust reconstruction of both primary and secondary climate variables is possible. [ABSTRACT FROM AUTHOR]

Presents a comparison of different methods in microstructural characterization of porous silicon (PS). Comparison of different methods used in studying PS microstructure; Components of PS; Importance of microstructure characterization in understanding the processes involved in luminescence.

Background: Cochlear implantation can be used when a patient's hearing cannot satisfactorily be improved after optimised hearing aid fitting. However, in patients with a cochlear nerve or brain disorder affecting hearing, the benefits of cochlear implants are not so straightforward. Methods: This paper describes a 58-year-old patient suffering from multiple sclerosis and profound sensorineural hearing loss, rehabilitated with a cochlear implant. Literature concerning cochlear implantation in demyelinating conditions was systematically reviewed using PubMed/Medline and Web of Science databases. Results: The patient's cochlear implantation was successful, with speech discrimination scores remaining above 90 per cent for eight years post-operatively. No previous cases of cochlear implantation with multiple sclerosis related hearing loss have been reported, despite the high incidence of hearing loss in multiple sclerosis patients. Conclusion: This paper demonstrates that multiple sclerosis lesions should not be an exclusion criterion in an otherwise suitable candidate for cochlear implantation. [ABSTRACT FROM AUTHOR]

Reports on the oxidation behavior of porous silicon and its link to illumination during etching. Autocatalytic oxidation behavior at room temperature caused by the unrelaxed surface; Removal using thermal treatment in a nitrogen atmosphere.

Examines the thermal oxidation of free-standing porous silicon thin film. Use of differential scanning calorimeter and thermogravimeter; Effect of humid storage condition on thermal oxidation rate; Calculation of the change in enthalpy and activation energy for first oxidation reaction; Analysis of backbond using Fourier transform infrared spectroscopy.

Color control of the white photoluminescence (PL) from carbon-incorporated silicon oxide is demonstrated. The carbon-incorporated silicon oxide was fabricated by carbonization of porous silicon in acetylene flow (at 650 and 850 °C) followed by wet oxidation (at 650 and 800 °C). It was shown that PL color can be controlled in the range of blue-white and yellow-white by selecting the porosity of starting porous silicon as well as the carbonization and oxidation temperatures. Low-temperature oxidation resulted in bluish light emission in lower porosity series, while high-temperature oxidation promoted yellow-white light emission. The maximal integral intensity of PL was observed after oxidation at 800 °C. It was shown that white PL from carbon-incorporated silicon oxide has blue and yellow-white PL bands originating from different light-emitting centers. The origin of blue PL is attributed to defects in silicon dioxide. Some trap levels at the interface of the carbon clusters and silicon oxide are suggested to be the origin of the yellow-white light emission. [ABSTRACT FROM AUTHOR]

Detailed studies on fossil remains of plants or animals in glacial lake sediments are rare. As a result, environmental conditions right at the moment of deglaciation of the large N-Hemisphere ice-sheets remain largely unknown. Here we study three deglacial phases of the Fennoscandian Ice Sheet as a unique, repeated element in a long sediment record preserved at Sokli in northern Finland. We summarize extensive multi-proxy data (diatoms, phytoliths, chironomids, pollen, spores, non-pollen palynomorphs, macrofossils, lithology, loss-on-ignition, C/N) obtained on glacial lake sediments dated to the early Holocene (ca. 10 kyr BP), early MIS 3 (ca. 50 kyr BP) and early MIS 5a (ca. 80 kyr BP). In contrast to the common view of an unproductive ice-marginal environment, our study reconstructs rich ecosystems both in the glacial lake and along the shores with forest on recently deglaciated land. Higher than present-day summer temperatures are reconstructed based on a large variety of aquatic taxa. Rich biota developed due to the insolation-induced postglacial warming and high nutrient levels, the latter resulting from erosion of fresh bedrock and sediment, leaching of surface soils, decay of plant material under shallow water conditions, and sudden decreases in lake volume. Aquatic communities responded quickly to deglaciation and warm summers and reflect boreal conditions, in contrast to the terrestrial ecosystem which responded with some delay probably due to time required for slow soil formation processes. Birch forest is reconstructed upon deglaciation of the large LGM ice-sheet and shrub tundra following the probably faster melting smaller MIS 4 and MIS 5b ice-sheets. Our study shows that glacial lake sediments can provide valuable palaeo-environmental data, that aquatic biota and terrestrial vegetation rapidly accommodated to new environmental conditions during deglaciation, and that glacial lake ecosystems, and the carbon stored in their sediments, should be included in earth system modeling. [ABSTRACT FROM AUTHOR]

The recent advancements of new quantitative tools compatible with plant macrofossil proxy data have revived its potential for paleoclimate research. Plant macrofossils are commonly used in so-called indicator-species approaches, using methodologies that are typically built on known observations linking modern plant distributions with climate. This allows complementary paleoclimate reconstructions using an approach that is not limited by the spatial availability of calibration samples obtained from surface sediments (e.g., pollen or chironomids). We aim to evaluate the impact that various methodological choices have on the plant-macrofossil based reconstructions of January and July temperature patterns for the Lateglacial (14–11 ka BP) period. We use a variety of classic and novel quantitative climate reconstruction algorithms with plant macrofossil assemblages from 13 sites of the Baltic States. We use unfiltered plant data to evaluate the ability of each method to also handle the presence of plants that might have a weak sensitivity to temperature. Additionally, we test the influence of another methodological choice – the choice of modern calibration region – on the reconstructed climate. Our findings indicate that, with no prior filtering of summer and winter-sensitive plants, temporal temperature variations can be reconstructed with methods that implement probability density functions. Although some disparities in reconstructions are seen between the tested algorithms, we note that the choice of calibration region bears a greater influence on the results. A calibration region that best represents the past environment should be chosen rather than one representing the same spatial extent as the fossil site(s). Moreover, for long-term reconstructions, a "dynamic calibration set" approach should be considered in future studies by using a range of calibration regions and mirroring the continuously changing broadscale environmental regime of the past. • Seasonal temperature reconstructions vary across climate reconstruction algorithms. • Calibration region impact is greater in January temperature reconstructions than July. • Proper calibration region evaluation is crucial before reconstructions. • Calibration regions should be based on environmental instead of geographical fit. [ABSTRACT FROM AUTHOR]

We compared DNA, pollen and macrofossil data obtained from Weichselian interstadial (age more than 40 kyr) and Holocene (maximum age 8400 cal yr BP) peat sediments from northern Europe and used them to reconstruct contemporary floristic compositions at two sites. The majority of the samples provided plant DNA sequences of good quality with success amplification rates depending on age. DNA and sequencing analysis provided five plant taxa from the older site and nine taxa from the younger site, corresponding to 7% and 15%of the total number of taxa identified by the three proxies together. At both sites, pollen analysis detected the largest (54) and DNA the lowest (10) number of taxa, but five of theDNAtaxawere notdetectedbypollenandmacrofossils. The finding of a larger overlap between DNA and pollen than between DNA and macrofossils proxies seems to go against our previous suggestion based on lacustrine sediments that DNA originates principally from plant tissues and less from pollen. At both sites, we also detected Quercus spp. DNA, but few pollen grains were found in the record, and these are normally interpreted as long-distance dispersal. We confirm that in palaeoecological investigations, sedimentary DNA analysis is less comprehensive than classical morphological analysis, but is a complementary and important tool to obtain a more complete picture of past flora. [ABSTRACT FROM AUTHOR]

Abstract: It is estimated that more than 95% of new drug candidates suffer from limited bioavailability . Particle size reduction and formation of amorphous form are commonly used techniques in modifying bioavailability of such drugs. In the present study, electrospraying was used in drug particle production. Three poorly soluble drugs were electrosprayed. Particle size was reduced down to micrometre range. Electrospraying was carried out in both atmospheric and reduced pressure, the latter in order to increase the proportion of amorphous content. The aim of the study was to examine the degree of crystallinity of the produced particles for both pressures. [Copyright &y& Elsevier]

Abstract: In the present study, electrospraying was used in drug particle-production. The objective of the research was to establish whether electrospraying can be carried out in reduced pressure in order to improve the drying process of the droplets. By this method, it is possible to produce drug particles relatively uniform in size, crystallinity and porosity. Drying the droplets in a reduced pressure is a more sensitive way to remove the solvent from the particles than, for example, the addition of heat. The efficiency of this drying method and particle morphology were studied using SEM, DSC, and XRD. Another objective was to workout whether the size of the produced particles can be estimated by a simple method. The maximum particle size was defined theoretically and compared to experimental results with good agreement. [Copyright &y& Elsevier]

Abstract: Six different types of mesoporous silicon microparticles were prepared to evaluate the effect of surface treatment and pore sizes on their properties as drug carriers. The studied porous silicon particles were as-anodized, thermally carbonized (TCPSi) and thermally oxidized (TOPSi) in addition to three novel ones: annealed TCPSi, annealed TOPSi and thermally hydrocarbonized porous silicon (THCPSi). Drug dissolution at pH 5.5 and physical and chemical stabilities after 3 months of storage were used as experimental models to investigate the loaded particles. Loading degrees of ibuprofen in the particles were determined by several methods before and after storage, and the results were in good agreement with each other. Loading improved the dissolution rate of ibuprofen in all the studied cases, while the hydrophilic TCPSi material resulted in the fastest dissolution and the most stable mesoporous microparticles. The release profiles of ibuprofen did not change markedly during storage. The effect of storage on the loading degrees of the other PSi microparticles than the unstable (easily oxidized) as-anodized porous silicon was not notable. [Copyright &y& Elsevier]

Background. There are no data on directly measured cardiorespiratory fitness combined coronary risk evaluation with respect to death from cardiovascular diseases and all-causes. We investigated the prognostic significance of risk scores and cardiorespiratory fitness with respect to cardiovascular disease and all-cause mortality. Methods. Cardiorespiratory fitness (maximal oxygen uptake, VO2peak) was measured by exercise test with an electrically braked cycle ergometer. The study is based on a random population-based sample of 1639 men (42–60 years) without history of type 2 diabetes or atherosclerotic cardiovascular diseases. Results. During an average follow-up of 16 years, a total of 304 deaths occurred. Independent predictors for all-cause death were European Score (for 1% increment, RR 1.15, 95% CI 1.10–1.20), VO2peak (for 1 MET increment, RR 0.84, 95% CI 0.78–0.89), when adjusted for C-reactive protein, alcohol consumption, serum high-density lipoprotein, waist-to-hip ratio, family history of coronary heart disease, exercise-induced ST changes and the use of medications for hypertension, dyslipidaemia or aspirin. Also, Framingham risk score was related to the risk of death (RR 1.05, 95% CI 1.03–1.07, P < 0.001). Subjects with high European or Framingham score and low VO2peak represent the highest risk group. Conclusion. An important finding is that the risk scores can be used to identify men for whom low cardiorespiratory fitness predicts an especially high risk for death from cardiovascular and any other cause. [ABSTRACT FROM AUTHOR]

Objective: To investigate the prognostic value of peak oxygen pulse, which is the amount of oxygen consumed per heart beat during exercise, and to compare the prognostic value of peak oxygen pulse and maximum oxygen uptake (V̇o2max) with respect to coronary heart disease (CHD) and overall death. Design: Prospective population-based study based on 1596 men without CHD or the use of β blockers at baseline. Results: The risk of CHD was 2.45 (95% CI 1.10 to 5.45) times higher in men with low peak oxygen pulse (< 13.5 ml/beat) than in those with high peak oxygen pulse (> 17.8 ml/beat) after adjustment for age, alcohol consumption, smoking, body mass index, blood pressure, serum lipids, diabetes, family history of CHD and ischaemic ST changes during exercise. During an average follow up of 14 years, 267 men died, 67 of them due to CHD. The respective risk for overall death was 1.79 (95% CI 1.21 to 2.65). The continuous variable V̇o2max was a stronger risk predictor than peak oxygen pulse for CHD and overall death. Conclusions: Assessment of oxygen pulse provides no complementary information to V̇o2max about cardiorespiratory fitness and prognosis for CHD. The analysis of respiratory gas exchange including the assessment of oxygen pulse during exercise does, however, provide an additional means for defining prognosis for patients with CHD. [ABSTRACT FROM AUTHOR]

Hohenthal U, Itälä M, Salonen J, Sipilä J, Rantakokko-Jalava K, Meurman O, Nikoskelainen J, Vainionpää R, Kotilainen P. Bronchoalveolar lavage in immunocompromised patients with haematological malignancy– value of new microbiological methods.Eur J Haematol 2005: 74: 203–211.© Blackwell Munksgaard 2005.Purpose: To assess the usefulness of new culture-independent microbiological methods to analyse bronchoalveolar lavage (BAL) fluid from haematological patients with clinical pneumonia.Patients and methods: Results of 135 BALs from 122 disease episodes in 99 patients treated between 1996 and 2002 were retrospectively analysed. Forty-three patients had undergone haematopoietic stem cell transplantation and 56 patients had been treated with conventional chemotherapy for haematological malignancy. In addition to conventional microbiological methods, polymerase chain reaction (PCR) tests forPneumocystis carinii, cytomegalovirus (CMV),Legionellasp., mycobacterium,Mycoplasma pneumoniae, andChlamydia pneumoniaeand theAspergillusantigen test were performed.Results: Three (2.2%) quantitative and four (3.0%) special bacterial cultures gave an aetiological diagnosis. A respiratory virus was isolated in 10 episodes (8.2%). The diagnostic yield increased to 35.6% (48 of 135) by other methods. TheP. cariniiPCR test was positive in 21 of 24 patients withP. cariniipneumonia, being the only microbiological indication ofP. cariniiin four cases. The CMV PCR test was positive in 18 patients, but in 14 patients the clinical significance of the finding remained unproven. TheAspergillusantigen test was positive in seven of nine patients with aspergillosis, being the only microbiological indication ofAspergillusin three cases. The result of BAL indicated commencement of specific antimicrobial treatment in 27 episodes (22.1%).Conclusion: The contribution of new culture-independent methods to the total diagnostic yield was of note. Among these methods, theP. cariniiPCR andAspergillusantigen tests proved the most valuable, while the CMV PCR test was not clinically useful. [ABSTRACT FROM AUTHOR]

Summary The data of two weed surveys of spring cereals (conducted in 1982–84 and 1997–99) in Finland were applied to study changes in the total abundance (the number of individuals and dry weight) of the weed community as well as in the abundance and frequency of occurrence of single species. The estimated overall mean for the differences in total dry weight was 31.1 kg ha[sup -1] and the differences in the total number of individuals was 46.6 individuals m[sup -2] with higher numbers in the 1990s. Most of the overall variability in dry weight (63%) and in number of individuals (57%) was attributable to variability between fields within the same farm. None of the environmental variables could explain the variability in the difference in dry weight, or in the number of individuals between decades. Descriptive analysis of the single species data revealed a higher abundance and frequency of occurrence of most species in the 1990s than in the 1980s. No statistically significant differences were detected in the number of individuals of species tolerant of sulfonylureas (pooled data on Galium spurium and Viola arvensis ) between decades. The results are discussed in relation to changes in the use of herbicides. [ABSTRACT FROM AUTHOR]