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Increasing production of biofuels has led to concerns about indirect land‐use change (ILUC). So far, significant efforts have been made to assess potential ILUC effects. But limited attention has been paid to strategies for reducing the extent of ILUC and controlling the type of LUC. This case study assesses five key ILUC mitigation measures to quantify the low‐ILUC‐risk production potential of miscanthus‐based bioethanol in Lublin province (Poland) in 2020. In 2020, a total area of 196 to 818 thousand hectare of agricultural land could be made available for biomass production by realizing above‐baseline yield developments (95–413 thousand ha), increased food chain efficiencies (9–30 thousand ha) and biofuel feedstock production on underutilized lands (92–375 thousand ha). However, a maximum 203–269 thousand hectare is considered legally available (not protected) and biophysically suitable for miscanthus production. The resulting low‐ILUC‐risk bioethanol production potential ranges from 12 to 35 PJ per year. The potential from this region alone is higher than the national Polish target for second‐generation bioethanol consumption of 9 PJ in 2020. Although the sustainable implementation potential may be lower, the province of Lublin could play a key role in achieving this target. This study shows that the mitigation or prevention of ILUC from bioenergy is only possible when an integrated perspective is adopted on the agricultural and bioenergy sectors. Governance and policies on planning and implementing ILUC mitigation are considered vital for realizing a significant bioenergy potential with low ILUC risk. One important aspect in this regard is monitoring the risk of ILUC and the implementation of ILUC mitigation measures. Key parameters for monitoring are land use, land cover and crop yields.  相似文献   
3.
A comparative study of two modifications of enzymic reduction of ethyl N-{2-{4-[(2-oxo-cyclohexyl)methyl]phe- noxy}ethyl} carbamate (1), an insect juvenile hormone bioanalog, was performed using Saccharomyces cerevisiae in two bioreactors of different size, 250-ml shake-flask and 1-l fermenter. The two major products of this reduction were obtained in 45–49% (w/w) yields but with > 99% enantiomeric purity. Their absolute configurations were assigned as ethyl (1S,2S)-N-{2-{4-[(2-hydroxycyclohexyl)methyl]phenoxy}ethyl}carbamate (2a) and ethyl (1R,2S)-N-{2-{4-[(2-hydroxycyclohexyl)methyl]phenoxy}ethyl}carbamate (3a).  相似文献   
4.
Selective enzymic esterification of free fatty acids, obtained from blackcurrant oil by chemical saponification, with n-butanol using four immobilized lipases under microwave irradiation and under classical heating was studied. A positive effect of microwave irradiation on chemical yields of the products of the enzymic reactions and specificity of lipases were observed in comparison with a controlled heating in an incubator equipped with shaking (classical heating) applied during the identical enzyme-mediated processes. The maximum quantity of -linolenic acid (30%) was obtained with Lipozyme used as biocatalyst of the reaction under microwave irradiation. The maximum quantity of butyl -linolenate (20%) was obtained by a Pseudomonas cepacia lipase catalyzed esterification under classical heating.  相似文献   
5.
Fourier Transform Infrared Radiation (FTIR) spectroscopy is one of the most powerful methods for the detection of gaseous constituents, aerosols, and dust in planetary atmospheres. Infrared spectroscopy plays an important role in searching for biomarkers, organics and biological substances in the Universe. The possibility of detection and identifications with FTIR spectrometer of bio-aerosol spores (Bacillus atrophaeus var. globigii=BG) in the atmosphere is discussed in this paper. We describe the results of initial spectral measurements performed in the laboratory and in the field. The purpose of these experiments was to detect and to identify bio-aerosol spores in two conditions: 1) In a closed chamber where the thermal contrast between the background and aerosols was large, and 2) In open air where the thermal contrast between the background and aerosols was small. The extinction spectrum of BG spores was deduced by comparing our measurements with models, and other measurements known from the literature. Our theoretical and experimental studies indicate that, during passive remote sensing measurements, it is difficult-but possible to detect and to identify bio-aerosol clouds by their spectral signatures. The simple spectral analysis described in the paper can be useful for the detection of various kinds of trace aerosols-not only in the Earth's atmosphere, but also during planetary missions in the environments of other astronomical objects such as planets, comets etc. We expect that the interpretation of data from spectrometric sounding of Venus and Mars during the current missions Mars and Venus Express, and later during the Rosetta mission will benefit from our experimental work and numerical modelling.  相似文献   
6.
Glutamate is the most abundant excitatory neurotransmitter in the brain and astrocytes are key players in sustaining glutamate homeostasis. Astrocytes take up the predominant part of glutamate after neurotransmission and metabolism of glutamate is necessary for a continuous efficient removal of glutamate from the synaptic area. Glutamate may either be amidated by glutamine synthetase or oxidatively metabolized in the mitochondria, the latter being at least to some extent initiated by oxidative deamination by glutamate dehydrogenase (GDH). To explore the particular importance of GDH for astrocyte metabolism we have knocked down GDH in cultured cortical astrocytes employing small interfering RNA (siRNA) achieving a reduction of the enzyme activity by approximately 44%. The astrocytes were incubated for 2h in medium containing either 1.0mM [(15)NH(4)(+)] or 100μM [(15)N]glutamate. For those exposed to [(15)N]glutamate an additional 100μM was added after 1h. Metabolic mapping was performed from isotope incorporation measured by mass spectrometry into relevant amino acids of cell extracts and media. The contents of the amino acids were measured by HPLC. The (15)N incorporation from [(15)NH(4)(+)] into glutamate, aspartate and alanine was decreased in astrocytes exhibiting reduced GDH activity. However, the reduced GDH activity had no effect on the cellular contents of these amino acids. This supports existing in vivo and in vitro studies that GDH is predominantly working in the direction of oxidative deamination and not reductive amination. In contrast, when exposing the astrocytes to [(15)N]glutamate, the reduced GDH activity led to an increased (15)N incorporation into glutamate, aspartate and alanine and a large increase in the content of glutamate and aspartate. Surprisingly, this accumulation of glutamate and net-synthesis of aspartate were not reflected in any alterations in either the glutamine content or labeling, but a slight increase in mono labeling of glutamine in the medium. We suggest that this extensive net-synthesis of aspartate due to lack of GDH activity is occurring via the concerted action of AAT and the part of TCA cycle operating from α-ketoglutarate to oxaloacetate, i.e. the truncated TCA cycle.  相似文献   
7.
The aim of this study was to conduct three-year monitoring of bone mineralization (BMC) and bone mineral density (BMD) of adolescent girls engaged in swimming at the time of attaining the peak bone mass and of their counterparts leading a rather sedentary life, considering the intakes of calcium, phosphorus and protein, as well as the proportions among those nutrients. Two groups of girls aged 11–13 years were studied 3 times at yearly intervals: untrained controls (n = 20) and those engaged in competitive swimming (n = 20). Bone density was determined by dual-energy X-ray absorptiometry (DXA) in the lumbar spine (L2 – L4). Nutrient intakes (energy, protein, calcium, phosphorus) were assessed from 24-h recalls. The group of swimmers had significantly lower BMI values than the control group. No systematic, significant between-group differences were found in nutrient intake or in bone mineralization variables. Calcium intake was below the recommended norm in all subjects but mean values of bone mineralization variables (BMC, BMD) steadily increased in both groups. The BMD z-scores proved negative throughout the three-year period of early adolescence in both groups of girls and that decrease was significant in swimmers. This could have been due to insufficient calcium intake as well as to inadequate calcium-to-phosphate and protein-to-calcium ratios and, when continued, might result in a decreased bone mass in adulthood.  相似文献   
8.
The experiment involved 30 clinically healthy prepubertal bitches aged approximately 70 days with an estimated initial body weight (BW) of 8 kg. The animals were randomly divided into two experimental groups (EI and EII) and a control group of 10 animals each. Group EI was administered 50 μg zearalenone (ZEN)/kg BW per os for 42 days, group EII received 75 μg zearalenone/kg BW per os for 42 days, and the control group was administered placebo per os for 42 days. The bitches were hysterectomized at the end of treatment, and samples of uterine tissue were collected for histological and morphometric analyses. The results of the study indicate that exposure to very low doses of ZEN (100% and 150% of the NOAEL) causes simple glandular hyperplasia of the endometrium accompanied by adenogenesis, angiogenesis, and vasodilatation with the related consequences. The noted changes were more pronounced in group EI and less visible in group EII in comparison with group C, which could be indicative of a hormetic dose response.  相似文献   
9.
Farm animals are at risk of exposure to zearalenone (ZEA) in feedstuffs, which may lead to aberrations in their reproductive development, thereby adversely affecting production outcomes. The objective of this study was to determine the effect of long-term (48 days), per os administration of low ZEA doses (50% [20 μg ZEA/kg body weight (bw)] and 100% [40 μg ZEA/kg bw] NOAEL values) on anatomopathological changes in the ovaries of sexually immature gilts. The experiment involved 12 clinically healthy gilts aged 2 months with an initial body weight of about 40 kg and a determined immune status. The animals were randomly divided into two experimental groups (E1, E2) and a control group (C; all n = 4). Group E1 received per os 20 μg ZEA/kg bw for 48 days; group E2 received per os 40 μg ZEA/kg bw for 48 days; and group C received per os placebo for 48 days. Analytical samples of the mycotoxin were administered daily per os in gelatine capsules before morning feeding. Animals were sacrificed at the end of the experiment. The results of anatomopathological examinations of the ovaries in immature gilts subjected to long-term, low-dose ZEA exposure showed that ZEA-induced experimental hyperoestrogenism lowered the proliferative ability of granulosa cells of the ovarian follicle walls and of the connective tissue of the ovarian stroma, in particular at the lower ZEA dose.  相似文献   
10.
Glutamate dehydrogenase (GDH) is a crucial enzyme on the crossroads of amino acid and energy metabolism and it is operating in all domains of life. According to current knowledge GDH is present only in one functional isoform in most animals, including mice. In addition to this housekeeping enzyme (hGDH1 in humans), humans and apes have acquired a second isoform (hGDH2) with a distinct tissue expression profile. In the current study we have cloned both mouse and human GDH constructs containing FLAG and (His)6 small genetically-encoded tags, respectively. The hGDH1 and hGDH2 constructs containing N-terminal (His)6 tags were successfully expressed in Sf9 cells and the recombinant proteins were isolated to ≥95 % purity in a two-step procedure involving ammonium sulfate precipitation and Ni2+-based immobilized metal ion affinity chromatography. To explore whether the presence of the FLAG and (His)6 tags affects the cellular localization and functionality of the GDH isoforms, we studied the subcellular distribution of the expressed enzymes as well as their regulation by adenosine diphosphate monopotassium salt (ADP) and guanosine-5′-triphosphate sodium salt (GTP). Through immunoblot analysis of the mitochondrial and cytosolic fraction of the HEK cells expressing the recombinant proteins we found that neither FLAG nor (His)6 tag disturbs the mitochondrial localization of GDH. The addition of the small tags to the N-terminus of the mature mitochondrial mouse GDH1 or human hGDH1 and hGDH2 did not change the ADP activation or GTP inhibition pattern of the proteins as compared to their untagged counterparts. However, the addition of FLAG tag to the C-terminus of the mouse GDH left the recombinant protein fivefold less sensitive to ADP activation. This finding highlights the necessity of the functional characterization of recombinant proteins containing even the smallest available tags.  相似文献   
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