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As an increasing share of the human population is being clustered in cities, urban areas have swiftly become the epicentres of anthropogenic carbon (C) emissions. Understanding different parts of the biogenic C cycle in urban ecosystems is needed in order to assess the potential to enhance their C stocks as a cost-efficient means to balance the C emissions and mitigate climate change. Here, we conducted a field measurement campaign over three consecutive growing seasons to examine soil respiration carbon dioxide (CO2) fluxes and soil organic carbon (SOC) stocks at four measurement sites in Helsinki, representing different types of tree-covered urban green space commonly found in northern European cities. We expected to find variation in the main drivers of soil respiration – soil temperature, soil moisture, and SOC – as a result of the heterogeneity of urban landscape and that this variation would be reflected in the measured soil respiration rates. In the end, we could see fairly constant statistically significant differences between the sites in terms of soil temperature but only sporadic and seemingly momentary differences in soil moisture and soil respiration. There were also statistically significant differences in SOC stocks: the highest SOC stock was found in inactively managed deciduous urban forest and the lowest under managed streetside lawn with common linden trees. We studied the impacts of the urban heat island (UHI) effect and irrigation on heterotrophic soil respiration with process-based model simulations and found that the variation created by the UHI is relatively minor compared to the increase associated with active irrigation, especially during dry summers. We conclude that, within our study area, the observed variation in soil temperature alone was not enough to cause variation in soil respiration rates between the studied green space types, perhaps because the soil moisture conditions were uniform. Thus, irrigation could potentially be a key factor in altering the soil respiration dynamics in urban green space both within the urban area and in comparison to non-urban ecosystems.

Today, city planners design urban futures by considering environmental degradation and climate mitigation. Here, we studied the greenhouse gas fluxes of urban lawns and meadows and linked the observations with plant functional types and soil properties. In eight lawns and eight meadows in the Helsinki metropolitan area, Finland, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes were measured using manual chambers, and plant functional types were recorded. Four of these sites, i.e. an irrigated lawn, an old mesic meadow, a non-irrigated lawn and a young dry meadow, were more intensively studied in 2021–2022. The process-based ecosystem model JSBACH was utilized together with the momentary observations collected approximately every second week on CO2 exchange to quantify the annual carbon (C) balance of these sites. On the remaining sites, we studied the initial dynamics of conversion from lawns to meadows by transforming parts of lawns to meadows in late 2020 and conducting measurements from 2020 to 2022. The mean photosynthetic production (GPP) of the irrigated lawn and mesic meadow was the highest in this study, whereas the dry meadow had the lowest GPP. The studied lawns were stronger C sinks compared to the meadows. However, the net exchange values were uncertain as the soils were not in equilibrium with the vegetation at all sites, which is common for urban habitats, and modelling the heterotrophic emissions was therefore challenging. The conversion from a lawn to a meadow did not affect the fluxes of CH4 and N2O. Moreover, the mesic meadow was more resistant to drought events than the non-irrigated lawn. Lastly, the proportion of herbaceous flowering plants other than grasses was higher in meadows than in lawns. Even though social and economic aspects also steer urban development, these results can guide planning when considering environmentally friendlier green spaces and carbon smartness.

Urban vegetation plays a role in offsetting urban CO2 emissions, mitigating heat through tree transpiration and shading, and acting as deposition surfaces for pollutants. The frequent occurrence of heatwaves and of concurrent drought conditions significantly disrupts the processes of urban trees, particularly their photosynthesis and transpiration rates. Despite the pivotal role of urban tree functioning in delivering essential ecosystem services, the precise nature of their response remains uncertain. We conducted sap flux density (Js) and leaf gas exchange measurements of four tree species (Tilia cordata, Tilia × europaea, Betula pendula, and Malus spp.) located in different urban green areas (Park, Street, Forest, and Orchard) in Helsinki, Finland. Measurements were made over two contrasting summers 2020 and 2021. Summer 2021 experienced a local heatwave and drought, whereas summer 2020 was more typical of Helsinki. In this study, we aimed to understand the responses of urban tree transpiration (measured with sap flux density) and leaf gas exchange to heatwave and drought conditions, and we examined the main environmental drivers controlling the tree transpiration rate during these periods. We observed varying responses of Js during the heatwave period at the four urban sites. When comparing the heatwave and no heatwave periods, a 35 %–67 % increase in Js was observed at the Park, Forest, and Orchard locations, whereas no significant change was seen at the Street site. Our results also showed that Js was higher (31 %–63 %) at all sites under drought conditions compared with non-dry periods. The higher Js values during the heatwave and dry periods were mainly driven by the high atmospheric demand for evapotranspiration, represented by the high vapor pressure deficit (VPD), suggesting that the trees were not experiencing severe enough heat or drought stress that stomatal control would have decreased transpiration. Accordingly, photosynthetic potential (Amax), stomatal conductance (gs), and transpiration (E) at the leaf level did not change during heatwave and drought periods, excluding the Park site where a significant reduction in gs was seen. VPD explained 55 %–69 % of the variation in the daily mean Js during heatwave and drought periods at all sites. At the Forest site, the increase in Js saturated after a certain VPD level, likely due to low soil water availability during these hot and dry periods. Overall, the heat and drought conditions were untypical of the region but not excessive enough to restrict stomatal control and transpiration, indicating that ecosystem services such as cooling were not at risk.

Cities have become increasingly interested in reducing their greenhouse gas emissions and increasing carbon sequestration and storage in urban vegetation and soil as part of their climate mitigation actions. However, most of our knowledge of the biogenic carbon cycle is based on data and models from forested ecosystems, despite urban nature and microclimates differing greatly from those in natural or forested ecosystems. There is a need for modelling tools that can correctly consider temporal variations in the urban carbon cycle and take specific urban conditions into account. The main aims of our study were to (1) examine the carbon sequestration potential of two commonly used street tree species (Tilia × vulgaris and Alnus glutinosa) growing in three different growing media by taking into account the complexity of urban conditions and (2) evaluate the urban land surface model SUEWS (Surface Urban Energy and Water Balance Scheme) and the soil carbon model Yasso15 in simulating the carbon sequestration of these street tree plantings at temporal scales (diurnal, monthly, and annual). SUEWS provides data on the urban microclimate and on street tree photosynthesis and respiration, whereas soil carbon storage is estimated with Yasso. These models were used to study the urban carbon cycle throughout the expected lifespan of street trees (2002–2031). Within this period, model performances were evaluated against transpiration estimated from sap flow, soil carbon content, and soil moisture measurements from two street tree sites located in Helsinki, Finland. The models were able to capture the variability in the urban carbon cycle and transpiration due to changes in environmental conditions, soil type, and tree species. Carbon sequestration potential was estimated for an average street tree and for the average of the diverse soils present in the study area. Over the study period, soil respiration dominated carbon exchange over carbon sequestration due to the high initial carbon loss from the soil after street construction. However, the street tree plantings turned into a modest sink of carbon from the atmosphere on an annual scale, as tree and soil respiration approximately balanced the photosynthesis. The compensation point when street tree plantings turned from an annual source into a sink was reached more rapidly – after 12 years – by Alnus trees, while this point was reached by Tilia trees after 14 years. However, these moments naturally vary from site to site depending on the growing media, planting density, tree species, and climate. Overall, the results indicate the importance of soil in urban carbon sequestration estimations.

Better monitoring, reporting, and verification (MRV) of the amount, additionality, and persistence of the sequestered soil carbon is needed to understand the best carbon farming practices for different soils and climate conditions, as well as their actual climate benefits or cost efficiency in mitigating greenhouse gas emissions. This paper presents our Field Observatory Network (FiON) of researchers, farmers, companies, and other stakeholders developing carbon farming practices. FiON has established a unified methodology towards monitoring and forecasting agricultural carbon sequestration by combining offline and near-real-time field measurements, weather data, satellite imagery, modeling, and computing networks. FiON's first phase consists of two intensive research sites and 20 voluntary pilot farms testing carbon farming practices in Finland. To disseminate the data, FiON built a web-based dashboard called the Field Observatory (v1.0, https://www.fieldobservatory.org/, last access: 3 February 2022). The Field Observatory is designed as an online service for near-real-time model–data synthesis, forecasting, and decision support for the farmers who are able to monitor the effects of carbon farming practices. The most advanced features of the Field Observatory are visible on the Qvidja site, which acts as a prototype for the most recent implementations. Overall, FiON aims to create new knowledge on agricultural soil carbon sequestration and effects of carbon farming practices as well as provide an MRV tool for decision support.

A significant proportion of the global carbon emissions to the atmosphere originate from agriculture. Therefore, continuous long-term monitoring of CO2 fluxes is essential to understand the carbon dynamics and balances of different agricultural sites. Here we present results from a new eddy covariance flux measurement site located in southern Finland. We measured CO2 and H2O fluxes at this agricultural grassland site for 2 years, from May 2018 to May 2020. In particular the first summer experienced prolonged dry periods, which affected the CO2 fluxes, and substantially larger fluxes were observed in the second summer. During the dry summer, leaf area index (LAI) was notably lower than in the second summer. Water use efficiency increased with LAI in a similar manner in both years, but photosynthetic capacity per leaf area was lower during the dry summer. The annual carbon balance was calculated based on the CO2 fluxes and management measures, which included input of carbon as organic fertilizers and output as yield. The carbon balance of the field was −57 ± 10 and −86 ± 12 g C m−2 yr−1 in the first and second study years, respectively.

Model-calculated forecasts of soil organic carbon (SOC) are important for approximating global terrestrial carbon pools and assessing their change. However, the lack of detailed observations limits the reliability and applicability of these SOC projections. Here, we studied whether state data assimilation (SDA) can be used to continuously update the modeled state with available total carbon measurements in order to improve future SOC estimations. We chose six fallow test sites with measurement time series spanning 30 to 80 years for this initial test. In all cases, SDA improved future projections but to varying degrees. Furthermore, already including the first few measurements impacted the state enough to reduce the error in decades-long projections by at least 1 t C ha−1. Our results show the benefits of implementing SDA methods for forecasting SOC as well as highlight implementation aspects that need consideration and further research.

Photosynthesis provides carbon for the synthesis of macromolecules to construct cells during growth. This is the basis for the key role of photosynthesis in the carbon dynamics of ecosystems and in the biogenic CO2 assimilation. The development of eddy-covariance (EC) measurements for ecosystem CO2 fluxes started a new era in the field studies of photosynthesis. However, the interpretation of the very variable CO2 fluxes in evergreen forests has been problematic especially in transition times such as the spring and autumn. We apply two theoretical needle-level equations that connect the variation in the light intensity, stomatal action and the annual metabolic cycle of photosynthesis. We then use these equations to predict the photosynthetic CO2 flux in five Scots pine stands located from the northern timberline to Central Europe. Our result has strong implications for our conceptual understanding of the effects of the global change on the processes in boreal forests, especially of the changes in the metabolic annual cycle of photosynthesis.

Photosynthesis, i.e. the assimilation of atmospheric carbon to organic molecules with the help of solar energy, is a fundamental and well-understood process. Here, we connect theoretically the fundamental concepts affecting C3 photosynthesis with the main environmental drivers (ambient temperature and solar light intensity), using six axioms based on physiological and physical knowledge, and yield straightforward and simple mathematical equations. The light and carbon reactions in photosynthesis are based on the coherent operation of the photosynthetic machinery, which is formed of a complicated chain of enzymes, membrane pumps and pigments. A powerful biochemical regulation system has emerged through evolution to match photosynthesis with the annual cycle of solar light and temperature. The action of the biochemical regulation system generates the annual cycle of photosynthesis and emergent properties, the state of the photosynthetic machinery and the efficiency of photosynthesis. The state and the efficiency of the photosynthetic machinery is dynamically changing due to biosynthesis and decomposition of the molecules. The mathematical analysis of the system, defined by the very fundamental concepts and axioms, resulted in exact predictions of the behaviour of daily and annual patterns in photosynthesis. We tested the predictions with extensive field measurements of Scots pine (Pinus sylvestris L.) photosynthesis on a branch scale in northern Finland. Our theory gained strong support through rigorous testing.

A prescribed fire experiment was conducted on 26 June 2009 in Hyytiälä, Finland, to study aerosol and trace gas emissions from prescribed fires of slash fuels and the effects of fire on soil properties in a controlled environment. A 0.8 ha forest near the SMEAR II measurement station (Station for Measuring Ecosystem-Atmosphere Relations) was cut clear; some tree trunks, all tree tops and branches were left on the ground and burned. The amount of burned organic material was ~46.8 tons (i.e., ~60 tons ha−1). The flaming phase lasted 2 h 15 min, the smoldering phase 3 h. Measurements were conducted on the ground with both fixed and mobile instrumentation, and in the air from a research aircraft. In the middle of the burning area, CO2 concentration peaked around 2000–3000 ppm above the baseline, and peak vertical flow velocities were ~9 m s−1, as measured with a 10 Hz 3-D sonic anemometer placed within the burn area. In the mobile measurements the peak particle number concentrations were approximately 1–2 × 106 cm−3 in the plume at a distance of 100–200 m from the burn area. On the ground at the SMEAR II station the geometric mean diameter of the mode with the highest concentration was 80 ± 1 nm during the flaming phase and in the middle of the smoldering phase, but, at the end of the smoldering phase, the largest mode was 122 nm. In the volume size distributions, geometric mean diameter of the largest volume mode was 153 nm during the flaming phase and 300 nm during the smoldering phase. The lowest single-scattering albedo of the ground-level measurements was 0.7 in the flaming-phase plume and ~0.9 in the smoldering phase. Elevated concentrations of several volatile organic compounds (VOC) (including acetonitrile, a biomass burning marker) were observed in the smoke plume at ground level. Measurements at the forest floor (i.e., a richly organic layer of soil and debris, characteristic of forested land) showed that VOC fluxes were generally low and consisted mainly of monoterpenes, and VOC flux peaked after the burning. After one year, the fluxes had nearly stabilized close to the level before the burning. The clear-cutting and burning of slash increased the total long-term CO2 release from the soil, and altered the physical, chemical and biological properties of the soil, such as increased the available nitrogen contents of the soil, which in turn, affected the long-term fluxes of greenhouse gases.

Heather (Calluna vulgaris), rosebay willowherb (Epilobium angustifolium), wavy hair-grass (Deschampsia flexuosa) and raspberry (Rubus idaeus) are typical species at boreal clear-cut sites. In this study, we measured their photosynthesis separately in the growing season of 2005 using a manual chamber. All measured species showed clear and species-specific seasonal cycles of photosynthetic activity (Pmax). The maxima of C. vulgaris and E. angustifolium occurred around June and July, while that of R. idaeus occurred as late as August. A simple model of photosynthetic activity is presented, addressing the photosynthesis of C. vulgaris was mainly explained by temperature history when the soil moisture is high. The activity of deciduous D. flexuosa also followed the temperature history, unlike the activities of E. angustifolium and R. idaeus. During a short drought, some shoots decreased their Pmax levels but none of the species showed similar reactions between individuals. We also observed that the comparison of the whole-plant Pmax or respiration of different-sized individuals were less scattered than the results based on full-grown leaf mass, implying that species-specific rates of photosynthesis at ground level are rather similar regardless of the plant size. Using species composition and continuous temperature and light measurements, we upscaled the species-specific process rates and integrated fixed and respired CO2 of ground vegetation for the entire 2005 growing season. The photosynthetic production per surface area of soil was 760 g C m−2 y−1 at the fertile site and 300 g C m−2 y−1 at the infertile site. During the snow-free period (18 April–21 November), the above ground parts of measured species released 75 g C m−2 y−1 at the infertile site. At the fertile site, E. angustifolium and R. idaeus respired 22 and 12 g C m−2 y−1, respectively.

Organic soil amendments are used to improve soil quality and mitigate climate change. However, their effects on soil structure, nutrient and water retention as well as greenhouse gas (GHG) emissions are still poorly understood. The purpose of this study was to determine the residual effects of a single field application of four ligneous soil amendments on soil structure and GHG emissions. We conducted a laboratory incubation experiment using soil samples collected from an ongoing soil-amendment field experiment at Qvidja Farm in south-west Finland, two years after a single application of four ligneous biomasses. Specifically, two biochars (willow and spruce) produced via slow pyrolysis, and two mixed pulp sludges from paper industry side-streams were applied at a rate of 9-22 Mg ha-1 mixed in the top 0.1 m soil layer. An unamended fertilized soil was used as a control. The laboratory incubation lasted for 33 days, during which the samples were kept at room temperature (21°C) and at 20%, 40%, 70% or 100% water holding capacity. Carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) fluxes were measured periodically after 1, 5, 12, 20 and 33 days of incubation. The application of ligneous soil amendments increased the pH of the sampled soils by 0.4-0.8 units, whereas the effects on soil organic carbon content and soil structure varied between treatments. The GHG exchange was dominated by CO2 emissions, which were mainly unaffected by the soil amendment treatments. The contribution of soil CH4 exchange was negligible (nearly no emissions) compared to soil CO2 and N2O emissions. The soil N2O emissions exhibited a positive exponential relationship with soil moisture. Overall, the soil amendments reduced N2O emissions on average by 13%, 64%, 28%, and 37%, at the four soil moisture levels, respectively. Furthermore, the variation in N2O emissions between the amendments correlated positively with their liming effect. More specifically, the potential for the pulp sludge treatments to modulate N2O emissions was evident only in response to high water contents. This tendency to modulate N2O emissions was attributed to their capacity to increase soil pH and influence soil processes by persisting in the soil long after their application., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Peltokangas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Climate change mitigation requires, besides reductions in greenhouse gas emissions, actions to increase carbon sinks in terrestrial ecosystems. A key measurement method for quantifying such sinks and calibrating models is the eddy covariance technique, but it requires imputation, or gap-filling, of missing data for determination of annual carbon balances of ecosystems. Previous comparisons of gap-filling methods have concluded that commonly used methods, such as marginal distribution sampling (MDS), do not have a significant impact on the carbon balance estimate. By analyzing an extensive, global data set, we show that MDS causes significant carbon balance errors for northern (latitude [Formula: see text]) sites. MDS systematically overestimates the carbon dioxide (CO[Formula: see text]) emissions of carbon sources and underestimates the CO[Formula: see text] sequestration of carbon sinks. We also reveal reasons for these biases and show how a machine learning method called extreme gradient boosting or a modified implementation of MDS can be used to substantially reduce the northern site bias., (© 2023. The Author(s).)

Incomplete knowledge of carbon (C) allocation dynamics in trees hinders accurate modeling and future predictions of tree growth. We studied C allocation dynamics in a mature Pinus sylvestris L. dominated forest with a novel analytical approach, allowing the first comparison of: (i) magnitude and δ13C of shoot, stem and soil CO2 fluxes (Ashoot, Rstem and Rsoil), (ii) concentration and δ13C of compound-specific and/or bulk non-structural carbohydrates (NSCs) in phloem and roots and (iii) growth of stem and fine roots. Results showed a significant effect of phloem NSC concentrations on tracheid growth, and both variables significantly impacted Rstem. Also, concentrations of root NSCs, especially starch, had a significant effect on fine root growth, although no effect of root NSC concentrations or root growth was detected on Rsoil. Time series analysis between δ13C of Ashoot and δ13C of Rstem or δ13C of Rsoil revealed strengthened C allocation to stem or roots under high C demands. Furthermore, we detected a significant correlation between δ13C of Rstem and δ13C of phloem sucrose and glucose, but not for starch or water-soluble carbohydrates. Our results indicate the need to include C allocation dynamics into tree growth models. We recommend using compound-specific concentration and δ13C analysis to reveal C allocation processes that may not be detected by the conventional approach that utilizes bulk organic matter., (© The Author(s) 2022. Published by Oxford University Press.)

Simulation models represent soil organic carbon (SOC) dynamics in global carbon (C) cycle scenarios to support climate-change studies. It is imperative to increase confidence in long-term predictions of SOC dynamics by reducing the uncertainty in model estimates. We evaluated SOC simulated from an ensemble of 26 process-based C models by comparing simulations to experimental data from seven long-term bare-fallow (vegetation-free) plots at six sites: Denmark (two sites), France, Russia, Sweden and the United Kingdom. The decay of SOC in these plots has been monitored for decades since the last inputs of plant material, providing the opportunity to test decomposition without the continuous input of new organic material. The models were run independently over multi-year simulation periods (from 28 to 80 years) in a blind test with no calibration (Bln) and with the following three calibration scenarios, each providing different levels of information and/or allowing different levels of model fitting: (a) calibrating decomposition parameters separately at each experimental site (Spe); (b) using a generic, knowledge-based, parameterization applicable in the Central European region (Gen); and (c) using a combination of both (a) and (b) strategies (Mix). We addressed uncertainties from different modelling approaches with or without spin-up initialization of SOC. Changes in the multi-model median (MMM) of SOC were used as descriptors of the ensemble performance. On average across sites, Gen proved adequate in describing changes in SOC, with MMM equal to average SOC (and standard deviation) of 39.2 (±15.5) Mg C/ha compared to the observed mean of 36.0 (±19.7) Mg C/ha (last observed year), indicating sufficiently reliable SOC estimates. Moving to Mix (37.5 ± 16.7 Mg C/ha) and Spe (36.8 ± 19.8 Mg C/ha) provided only marginal gains in accuracy, but modellers would need to apply more knowledge and a greater calibration effort than in Gen, thereby limiting the wider applicability of models., (© 2020 John Wiley & Sons Ltd.)

Scots pine (Pinus sylvestris L.) is one of the most important conifers in Northern Europe. In boreal forests, over one-third of net primary production is allocated to roots. Pioneer roots expand the horizontal and vertical root systems and transport nutrients and water from belowground to aboveground. Fibrous roots, often colonized by mycorrhiza, emerge from the pioneer roots and absorb water and nutrients from the soil. In this study, we installed three flatbed scanners to detect the daily growth of both pioneer and fibrous roots of Scots pine during the growing season of 2018, a year with an unexpected summer drought in Southern Finland. The growth rate of both types of roots had a positive relationship with temperature. However, the relations between root elongation rate and soil moisture differed significantly between scanners and between root types indicating spatial heterogeneity in soil moisture. The pioneer roots were more tolerant to severe environmental conditions than the fibrous roots. The pioneer roots initiated elongation earlier and ceased it later than the fibrous roots. Elongation ended when the temperature dropped below the threshold temperature of 4 °C for pioneer roots and 6 °C for fibrous roots. During the summer drought, the fibrous roots halted root surface area growth at the beginning of the drought, but there was no drought effect on the pioneer roots over the same period. To compare the timing of root production and the aboveground organs' production, we used the CASSIA model, which estimates the aboveground tree carbon dynamics. In this study, root growth started and ceased later than growth of aboveground organs. Pioneer roots accounted for 87% of total root productivity. We suggest that future carbon allocation models should separate the roots by root types (pioneer and fibrous), as their growth patterns are different and they have different reactions to changes in the soil environment., (© The Author(s) 2020. Published by Oxford University Press.)

Isaac Newton's approach to developing theories in his book Principia Mathematica proceeds in four steps. First, he defines various concepts, second, he formulates axioms utilising the concepts, third, he mathematically analyses the behaviour of the system defined by the concepts and axioms obtaining predictions and fourth, he tests the predictions with measurements. In this study, we formulated our theory of boreal forest ecosystems, called NewtonForest, following the four steps introduced by Newton. The forest ecosystem is a complicated entity and hence we needed altogether 27 concepts to describe the material and energy flows in the metabolism of trees, ground vegetation and microbes in the soil, and to describe the regularities in tree structure. Thirtyfour axioms described the most important features in the behaviour of the forest ecosystem. We utilised numerical simulations in the analysis of the behaviour of the system resulting in clear predictions that could be tested with field data. We collected retrospective time series of diameters and heights for test material from 6 stands in southern Finland and five stands in Estonia. The numerical simulations succeeded to predict the measured diameters and heights, providing clear corroboration with our theory.

Objective: To determine the factors associated with prolonged latency periods in preterm prelabor rupture of membrane (PPROM)., Methods: This retrospective study analyzed data from singleton pregnant women with gestational age between 28 and 34 weeks suffering from PROM. Multivariate regression analysis was used to evaluate the association between the factors and latency period ≥ 2 and ≥ 7 days., Results: A total of 231 cases of PPROM were included. Prolong latency period ≥2 and 7 days were achieved in 141 (61%) and 54 (23.4%) cases. Higher gestational age at PPROM and cervical dilatation >2 cm were associated with a shorter latency period <2 days. Multiparity and presence of uterine contraction at admission were associated with a shorter latency period <7 days. Prophylactic antibiotics [odds ratio (ORs) 6.69, 95% confidence interval (CI) 3.0-14.89], and tocolysis (ORs 2.74, 95%CI 1.25-6.02) were factors associated with latency period ≥ 2 days. Only prophylactic antibiotics (ORs 7.7, 95%CI 2.54-23.34) was a factor associated with latency period ≥7 days., Conclusions: Prophylactic antibiotics and tocolysis are two major factors associated with latency period ≥2 days in PPROM, where prophylactic antibiotics is the main factor associated with latency period ≥7 days in PPROM.

The control of tree growth vs environment by carbon sources or sinks remains unresolved although it is widely studied. This study investigates growth of tree components and carbon sink-source dynamics at different temporal scales. We constructed a dynamic growth model 'carbon allocation sink source interaction' (CASSIA) that calculates tree-level carbon balance from photosynthesis, respiration, phenology and temperature-driven potential structural growth of tree organs and dynamics of stored nonstructural carbon (NSC) and their modifying influence on growth. With the model, we tested hypotheses that sink demand explains the intra-annual growth dynamics of the meristems, and that the source supply is further needed to explain year-to-year growth variation. The predicted intra-annual dimensional growth of shoots and needles and the number of cells in xylogenesis phases corresponded with measurements, whereas NSC hardly limited the growth, supporting the first hypothesis. Delayed GPP influence on potential growth was necessary for simulating the yearly growth variation, indicating also at least an indirect source limitation. CASSIA combines seasonal growth and carbon balance dynamics with long-term source dynamics affecting growth and thus provides a first step to understanding the complex processes regulating intra- and interannual growth and sink-source dynamics., (© 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.)

The satellite-derived normalized difference vegetation index (NDVI), which is used for estimating gross primary production (GPP), often includes contributions from both mosses and vascular plants in boreal ecosystems. For the same NDVI, moss can generate only about one-third of the GPP that vascular plants can because of its much lower photosynthetic capacity. Here, based on eddy covariance measurements, we show that the difference in photosynthetic capacity between these two plant functional types has never been explicitly included when estimating regional GPP in the boreal region, resulting in a substantial overestimation. The magnitude of this overestimation could have important implications regarding a change from a current carbon sink to a carbon source in the boreal region. Moss abundance, associated with ecosystem disturbances, needs to be mapped and incorporated into GPP estimates in order to adequately assess the role of the boreal region in the global carbon cycle.

The aim of this study was to determine the predictive value of the combination of plasma-soluble fms-like tyrosine kinase 1 (sFlt-1) and uterine artery Doppler for the detection of preeclampsia in women of advanced age at 16-18 weeks of gestation and to identify associations between other pregnancy complications and abnormalities of these combined tests. The maternal plasma sFlt-1 level was measured, and uterine artery Doppler was performed at 16-18 weeks of gestation in 314 cases of elderly gravida. The main outcome was preeclampsia. Fourteen women (4.46%) developed preeclampsia. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of uterine artery Doppler combined with plasma sFlt-1 for preeclampsia prediction were 28.6, 95.7, 23.5 and 96.6%, respectively. For the prediction of early-onset preeclampsia, the sensitivity, specificity, PPV and NPV were 80, 95.8, 23.5 and 99.7%, respectively. Patients with abnormal uterine artery Doppler findings and an abnormal plasma s Flt-1 level (greater than 1724.5 pg ml(-1)) had a higher risk of preterm delivery (relative risk (RR)=3.38, 95% confidence interval (CI) 1.47-7.59), neonatal respiratory distress syndrome (RR=52.06, 95% CI 5.71-474.45) and perinatal death (RR=17.35, 95% CI 1.13-265.64). Our findings indicate that the combination of uterine artery Doppler and sFlt-1 level at 16-18 weeks of gestation in cases of elderly gravida has a high predictive value for early-onset preeclampsia, but not for overall preeclampsia. This combination test may be a useful early second trimester screening test for the prediction of early-onset preeclampsia in cases of elderly gravida.

Background: Preterm prelabor rupture of membrane (PPROM) causes maternal and neonatal complications. Prophylactic antiobiotics were used in the management of PPROM. The objectives of this retrospective study were to compare clinical course and outcome of PPROM managed expectantly with prophylactic antibiotics and antenatal corticosteroids with those without prophylactic antibiotics and antenatal corticosteroids., Results: A total of 170 cases of singleton pregnant women with gestational age between 28-34 weeks suffering from PROM during January 1998 to December 2009 were included; 119 cases received prophylactic antibiotics and antenatal corticosteroids while 51 cases did not received prophylactic antibiotics and antenatal corticosteroids. Median latency period in the study group was significantly longer than in the control group (89.8 vs. 24.3 hours, P < 0.001). The percentage of patients who did not deliver within 48 hours and within 7 days in the study group were also significantly higher than in control group (64.7 vs. 31.4%, P < 0.001 and 29.4 vs. 7.8%, P = 0.002, respectively). Maternal infectious morbidity was comparable between groups (17.6% vs. 13.7%, P = 0.52). Neonatal infectious morbidity was significantly lesser in study group than control group (21% vs. 35.3%, p = 0.04)., Conclusions: Latency period of PPROM after using prophylactic antibiotics and antenatal corticosteroids increased while neonatal infectious morbidity was low. But maternal infectious morbidity was not increased. This retrospective study confirms the benefit of prophylactic antibiotics and antenatal corticosteroids in management of PPROM.

Aims: To assess whether terbutaline is able to prolong the latency period in women with preterm premature rupture of membranes (PPROM) and compare maternal and neonatal morbidity and mortality in the terbutaline and nontocolysis groups., Methods: This study retrospectively analyzed data from women with singleton pregnancies (gestational ages between 28 and 34 weeks) suffering from PPROM from January 1998 to December 2009., Results: A total of 163 cases of PPROM were analyzed; there were 61 cases (37.4%) in the terbutaline group and 102 cases (62.6%) in the nontocolysis group. The median latency period was comparable in the two groups (78 vs. 75 h, p = 0.44). The percentage of patients who did not deliver within 48 h was significantly higher in the terbutaline group compared with the nontocolysis group (78.7 vs. 62.7%, p = 0.03). There were no differences in maternal morbidity and mortality, and neonatal mortality between the two groups. Interestingly, neonatal infectious morbidity was significantly higher in the terbutaline group when compared with the nontocolysis group., Conclusions: Terbutaline cannot prolong the latency period in PPROM. There were no differences in maternal morbidity and mortality. However, neonatal infectious morbidity was higher in the terbutaline group., (Copyright © 2012 S. Karger AG, Basel.)

Although there is increasing evidence of the temporal correlation between photosynthesis and soil CO(2) efflux, no study has so far tested its generality across the growing season at multiple study sites and across several time scales. Here, we used continuous (hourly) data and applied time series analysis (wavelet coherence analysis) to identify temporal correlations and time lags between photosynthesis and soil CO(2) efflux for three forests from different climates and a grassland. Results showed the existence of multi-temporal correlations at time periods that varied between 1 and 16 d during the growing seasons at all study sites. Temporal correlations were strongest at the 1 d time period, with longer time lags for forests relative to the grassland. The multi-temporal correlations were not continuous throughout the growing season, and were weakened when the effect of variations in soil temperature and CO(2) diffusivity on soil CO(2) efflux was taken into account. Multi-temporal correlations between photosynthesis and soil CO(2) efflux exist, and suggest that multiple biophysical drivers (i.e. photosynthesis, soil CO(2) diffusion, temperature) are likely to coexist for the regulation of allocation and transport speed of carbon during a growing season. Future studies should consider the multi-temporal influence of these biophysical drivers to investigate their effect on the transport of carbon through the soil-plant-atmosphere continuum., (No claim to original US government works. New Phytologist © 2011 New Phytologist Trust.)

The first step in the oxidative metabolism of cocaine is N-demethylation to norcocaine, which is further N-hydroxylated to more toxic N-hydroxynorcocaine. In this study we examined the kinetics of norcocaine N-hydroxylation mediated by cytochrome P450 (CYP) in mouse and human liver microsomes. N-hydroxynorcocaine was identified by analytical HPLC-MS after incubation of norcocaine with mouse liver microsomes in the presence of NADPH. In mouse liver microsomes, there was no apparent difference in Km values for norcocaine N-hydroxylation between male and female microsomes, while the Vmax rate was approximately two times higher in female than in male microsomes (34+/-10 v. 16+/-4 pmol/min per mg protein). The Km value for norcocaine N-hydroxylation in human liver microsomes was approximately three times higher than that observed in comparable incubations using mouse liver microsomes, whereas the Vmax rate was ten times lower. Both cocaine and norcocaine induced type I difference spectra upon interaction with CYP in mouse liver microsomes. In contrast, in human microsomes both type I and type II spectra were recorded. In the 0.01 to 1 mM concentration range, cocaine and norcocaine inhibited mouse microsomal testosterone 6alpha-, 7alpha- and 16alpha-hydroxylation reactions by 20% to 30%. Testosterone 6beta- and 15alpha-hydroxylations were blocked by 60% and 50%, respectively, by 1 mM norcocaine, while only 40% inhibition was obtained with 1 mM cocaine. Coumarin 7-hydroxylation and pentoxyresorufin O-deethylation were inhibited by 50% by 1 and 0.4 mM norcocaine, respectively. In contrast, 10 and 2 mM cocaine, respectively, were needed to obtain the same degrees of inhibition. In human liver microsomes, 1 mM norcocaine and cocaine blocked testosterone 6beta-hydroxylase by 60% and 40%, respectively. Coumarin 7-hydroxylation was inhibited by only 30% by norcocaine (5.4 mM) and cocaine (10 mM). Norcocaine N-hydroxylation in mouse and human liver microsomes was blocked by 30% and 60%, respectively, by alpha-naphthoflavone (0.1 mM). The reaction was inhibited by 30-40% by metyrapone, cimetidine and gestodene at a concentration of 1 mM in mouse microsomes, while in human microsomes, 70% inhibition was obtained with 1 mM metyrapone and cimetidine. Taken together, these results indicate that (1) norcocaine N-hydroxylation is at least partly a CYP-mediated reaction, (2) the rate of reaction is considerably lower in human liver microsomes than in mouse liver microsomes and (3) several CYP subfamilies including 1A, 2A, 3A and possibly 2B may contribute to the formation of N-hydroxynorcocaine.