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A 13.0 cal ka BP pollen record from Twin Ponds, Vermont, provides new insights into the climate history of the northeastern United States. Modern analogs were used to produce qualitative and quantitative climate reconstructions for Twin Ponds. The Twin Ponds record was compared with nearby Knob Hill Pond to develop a Vermont reconstruction that was compared with reconstructions from two sites at a similar latitude. Postglacial warming at 11.5 cal ka BP followed a cool, wet Younger Dryas and was the largest temperature change of the record. The warmest, driest conditions occurred at ca. 9.0 cal ka BP, followed by an increase in moisture. Latitudinal and elevational shifts in the location of modern analogs from 5.7 to 4.0 cal ka BP were used to infer cooling and increased moisture during the Tsuga canadensis decline. Analysis of the timing of pollen events between the two Vermont sites suggests a more rapid decline in T. canadensis at the more northern Knob Hill Pond and further supports the possibility that colder temperatures contributed to this event. The other northern sites show similar trends until 2.5 cal ka BP, when precipitation in the easternmost site diverges, indicating the establishment of modern climatic gradients. [ABSTRACT FROM AUTHOR]

Changes in vegetation in North America indicate Holocene shifts in the latitudinal temperature gradient along the western margin of the North Atlantic. Tree taxa such as oak (Quercus) and birch (Betula) experienced opposing directions of change across different latitudes consistent with changes in temperature gradient steepness. Pollen‐inferred temperatures from 34 sites quantify the gradient changes and reconstruct a long‐term northward steepening in summer and southward steepening in winter. From 4.8 to 3.8 ka, an oscillation in tree distributions interrupted the long‐term trends as a steep temperature gradient developed north of 43.5°N. The shift likely limited cold outbreaks to the south, producing anomalously high summer temperatures at 42–43.5°N, and enabling a northward expansion of oak forests. The forest and temperature gradient changes appear consistent with orbital and ice sheet forcing as well as millennial variability in the North Atlantic pressure field analogous to the North Atlantic Oscillation on interannual time scales. Plain Language Summary: In the Northern Hemisphere, average temperatures decline with latitude as climates cool toward the pole. Changes in this temperature pattern have significant consequences for weather systems and ecosystems. Past changes likely impacted the geographic extent of summer warmth and winter freezing that can determine where tree species can grow. In this study, fossil evidence of ancient tree distributions revealed how the poleward temperature gradient near the Atlantic coast of North America fluctuated over the past 11,700 years. Long‐term forest and temperature changes developed in response to the deglaciation of Canada and Earth's slow orbital changes. However, a particularly striking change 4,800–3,800 years ago briefly expanded oak‐hickory forests into mid‐latitude highlands otherwise dominated by cold‐tolerant northern tree species. The forest histories demonstrate the potential for ecosystems to change rapidly in the future, but also how fossil records can reveal poorly understood patterns and processes of millennial‐scale climate variability. Temperature patterns detected here may be analogous to patterns of climate variability in the North Atlantic region at monthly‐to‐annual scales. Key Points: A major ecotone in eastern North America, which is linked to the latitudinal temperature gradient, shifted repeatedly during the HolocenePollen‐inferred temperatures from different latitudes across the ecotone reveal gradient responses to deglaciation and orbital changeChanges at 4.8–3.8 ka also indicate millennial‐scale variability with patterns analogous to the North Atlantic Oscillation [ABSTRACT FROM AUTHOR]

In the current context of industrialization, chemical and radioactive pollution is a concern for environmental protection and interference with human health. Care for environmental protection also includes vegetation that grows spontaneously in potentially contaminated places, thus avoiding illness among the population if consumed. The study area is located at 4.5km SSE from downtown Bacău City, Romania and is the result of the manufacture of H3PO4 through the wet method. In this study, the concentrations of cadmium (Cd), lead (Pb), and copper (Cu) in soil, and in Artemisia absinthium L. (root and aerial part) medicinal plant that grows spontaneously in a polluted area, respectively the phosphogypsum landfill from Bacău, were evaluated for two consecutive years, 2014 and 2015. The main purpose of this paper is to investigate the level of bioaccumulation in plants and soil concentrations immediately after definitive ending of the commercial activity of Amurco SA Bacău located in the southern industrial area of the city and 10 years after ending of the dumping of the phosphogypsum storage. The obtained results were compared with the reference values according to the legislation on environmental pollution assessment. The average values obtained for soil Cd concentration are close to the normal values for samples taken from the phosphogypsum landfill, respectively 1 mg/kg in both studied years. However, some values for Cd in the soil were above the normal value, respectively 1.227 mg/kg in 2014 and 2.665 mg/kg in 2015. We note that in 2015, unlike in 2014, thus evidencing the effect of accumulation over time, the presence of values above the normal value also in the case of Cd in the soil (33.034 mg/kg) and in the case of Pb in the soil (34.117 mg/kg). The concentration of heavy metals (Cu, Pb and Cd) in the plant material harvested in 2014 and 2015 has exceeded the maximum concentration recommended by the Codex Alimentarius Commission (CAC) for most samples. Also, the values for γ radioactivity bioaccumulation factors are up to four times higher in the roots than in the aerial parts. In terms of biometric parameters, there was observed a strong direct correlation between the length of the aerial parts and level of gamma radioactivity in soil samples at both depths. The results registered for the plants grown on the top of the landfill show that the high values of heavy metals bioaccumulation degree from the aerial parts can be caused by adsorption of particles from the air. Thus, it can be concluded that even if the influence of the phosphogypsum landfill is only local, a monitoring program of aerial transport is needed. [ABSTRACT FROM AUTHOR]

Biomass is a very important source for the production of biofuels. During the hydrolysis step of the process for obtaining biofuels the rate of decomposition of biomass is strictly related to its organic matter content and the operating mode of the facilities. This paper highlights the effect of different pretreatments on the composition of biomass at the molecular level using Fourier Transform Infrared Spectroscopy (FTIR) and Principal Component Analysis (PCA). For this experiment, a mixture of vegetable waste as a potential source of abundant and sustainable feedstock for biofuels was used. Vegetable wastes were subjected to physical and chemical pretreatment. The physical pretreatment comprised in exposing the wastes at a temperature of 120°C for 20 minutes in an autoclave. For the chemical pretreatment, Schweizer reagent, sodium hydroxide and urea were used. FTIR analysis shows that the chemical pretreatment leads to important changes at the molecular structures level, associated with the presence of sucrose, amide, phospholipids and carboxylic acids. Moreover, results of PCA analyses confirm that the region of C=O and C=C stretching vibrations (1500-1800 cm-1) are sensitive to NaOH and urea pretreatments on the biomass. For the physical pretreatment, no substantial changes at the molecular structure level were observed. [ABSTRACT FROM AUTHOR]

In the present study, the effects of two methods for thermal sanitization of soil, by oven and by autoclave, and two non-ionizing radiation sterilization methods, UVC and microwave on pH, conductivity, dry weight, total number of germs and respiration of samples from neutral commercial soil were evaluated, using international standard methods. Also, the infrared and UV-VIS spectroscopy were applied for the determination of chemical properties and structural characterization of humic acid and hydrophilic indexes at molecular level. The independent variable parameters used in the study were the time and temperature of sterilizing process and also the radiation dose applied. The results had shown a few variation of pH regardless the method of sanitization. However, the initial conductivity (EC) of soil (44 µS/cm for control) increases after UVC (54 µS/cm) and oven (68 µS/cm) treatments. Concerning microbial inactivation, the autoclave method is more efficiently because the initial NTG (total number of bacteria germs) of 96 × 109 cells/g decreased under the detection limit after this treatment. For autoclaved soil, the CO2 level remains constant. After application of oven treatment, an intensification of metabolic processes in the sense of degradation of organic matter occurred besides reducing the number of microorganisms. Also, the result reflected a similar tendency between the hydrophilic component and humic acid content. Variation of hydrophilic compounds of humic acids calculated for soil exposed to different techniques suggested that sanitization techniques applied to the commercial soil induced modification of soil and organic compounds, besides sanitation. [ABSTRACT FROM AUTHOR]

The aim of our investigations was to assess the potential ecotoxicological effects induced by complex chemical mixtures of anaerobically digested sewage sludge. The sensitivity of monocotyledonae cereal (Triticum aestivum L.) test plant to various sanitization treatments of anaerobic stabilized sewage sludge was evaluated. Several biometrical and biochemical response indicators were selected as endpoint in this ecotoxicological tests. Thus, the ecotoxicity of sewage sludge was evaluated through the responses of germination rate, root and stem system growth, the chlorophyll pigments and phenol contents. The sanitization treatments, respectively pasteurization and UVC exposure were applied to sewage sludge according to an experimental design wherein untreated sewage sludge was added as control sample. The results confirmed the increasing of untreated sewage sludge toxicity with the increasing of exposure time. In the case of wheat seeds kept in contact for 6 hours with the sludge treated for 30 minutes at 35°C it was observed an ascending trend of the germination rate respons with the sludge concentration. This involves a decrease of ecotoxicity compared with the one corresponding with untreated sewage sludge. Also, we appreciated a reduced ecotoxicity of low irradiated sludge than that of medium or high heat treatment in terms of germination rate inhibition measured after 14 days from the experiment beginning. By application of a medium UV dose, a low ecotoxicity was also observed, after 12h exposure time. Furthermore, the important role of phenolic compounds that protects the cell structures of the plant from environmental stress was confirmed by Principal Component Analysis. [ABSTRACT FROM AUTHOR]

This study investigated the effects of a plant growth- promoting rhizobacteria on soil treated with phosphogypsum (PG) as the mineral additive. The indigenous bacterial strain was isolated from PG polluted soil and identified as Bacillus megaterium, which is able to stimulate plant growth under heavy metals stress conditions. There were nine treated soils with three replicates: (1) control (without PG and inoculums (I) application); (2) control with inoculums (without PG application); (3) - (9) PG application (1, 2, 3, 4, 6, 8 and 10%) equivalent to 10 - 220 t ha-1. The objectives of this study consisted on monitoring the heavy metals levels (Cu, Fe, Zn, Mn) in the body of soybean (Glycine max) and evaluation of the human health risk. This work demonstrates that PG-BM30 coupling effect in the soil on seed germination, seedling growth, biomass accumulation and heavy metals bioaccumulation do not exhibit risk to human health. [ABSTRACT FROM AUTHOR]

INTRODUCTION: COPD exacerbation represents a condition determined by the respiratory system`s incapacity to maintain good alveolar ventilation, with hypoxemia, hypercapnia and respiratory acidosis. Subsequently, there are cardiovascular and neurological complications with vital risk for the patient. MATERIAL AND METHODS: Between 2012 and February 2014 we used noninvasive ventilation in 7 cases diagnosed with COPD and respiratory failure. Some of them, which had severe exacerbation, were directly admitted in the Intensive Care Unit and needed tracheal intubation and mechanical ventilation. After improving, they were transferred in our department and continued noninvasive ventilation with BIPAP- ST on facial mask. The initial pressures were 4/8 cm H2O and were modifi ed based on arterial blood gas and acid-base balance. The noninvasive ventilation was used in daytime in four periods of two hours and six hours in the night. RESULTS: The patients had a good and rapid recovery with carbon dioxide level lowered almost to the normal values and concomitantly with oxygen partial pressure growth. The patients could be mobilized after a few days and in 7-10 days were discharged. Most of them now use NIV only in the night and have a better quality of life. CONCLUSIONS: NIV introduction in our department practice determined a faster recovery of severe patients with shortening hospital admittance and costs lowering. [ABSTRACT FROM AUTHOR]