59 research outputs found
Niittomurskaimet kuivattavat rehua tasaveroisesti
Vastalevyllä tai -kammalla varustetut varsta- ja kumitelamurskaimet ovat tasaveroisia rehun kuivumisen edistäjiä. Kulmikkailla varstoilla varustetussa niittomurskaimessa suuri murskausvoimakkuus voi jopa hidastaa kuivumista. Sen sijaan pyöreillä varstoilla varustetussa koneessa murskausvoimakkuudella ei yleensä ole merkitystä.vo
Forest biodiversity, carbon sequestration, and wood production: modeling synergies and trade-offs for ten forest landscapes across Europe
Original ResearchEurope’s forests provide vital habitat for biodiversity and essential ecosystem services
whose provision must be sustained or enhanced over the coming century. However,
the potential to secure or increase forest ecosystem services, while securing the
habitat requirements of taxa remains unclear, especially within the context of uncertain
climate and socio-economic developments. To tease out the associated trade-offs
and synergies, we used 10 case study landscapes within nine countries throughout
Europe. Starting with the current status of the forests in the case study landscapes,
we simulated forest development 100 years into the future. Simulations were embedded
in three combined climate and socio-economic frame scenarios based on global and
European policies which varied in their climate change mitigation efficiency. Scenarios
were translated into country specific projections of climate variables, and resultant
demands for wood products. Forest management regimes were projected to vary in
response to these scenarios at local scales. The specific combinations of alternative
forest management practices were based on parallel research and input from local forest
stakeholders. For each case study, a specific forest growth simulator was used. In
general, the climate scenarios applied did not cause fundamentally different ecosystem
service outputs at the case study level. Our results revealed almost no reduction in outcomes for biodiversity indicators with an increase in wood production, and in some
cases synergistic results occurred when diversity was actively promoted as part of the
management concept. Net carbon uptake was not strongly correlated with biodiversity,
indicating that biodiversity-friendly forest management doesn’t need to curtail carbon
sequestration. Notably, we obtained heterogeneous results for the relation between
sustainable wood production and net carbon uptake. Most scenarios resulted in a
more or less reduced net carbon uptake over the long term, often due to stand age
class distribution shifts. Levels of sustainable wood production varied widely during
the simulation period, from significant increases (Sweden, Lithuania) to minor changes
(Slovakia, Turkey) and slight decreases (Ireland, Netherlands). We place our results
within the larger context of European forest policy and the challenges of simulating and
contrasting forest biodiversity and the ecosystem services that societies depend on outcomes for biodiversity indicators with an increase in wood production, and in some
cases synergistic results occurred when diversity was actively promoted as part of the
management concept. Net carbon uptake was not strongly correlated with biodiversity,
indicating that biodiversity-friendly forest management doesn’t need to curtail carbon
sequestration. Notably, we obtained heterogeneous results for the relation between
sustainable wood production and net carbon uptake. Most scenarios resulted in a
more or less reduced net carbon uptake over the long term, often due to stand age
class distribution shifts. Levels of sustainable wood production varied widely during
the simulation period, from significant increases (Sweden, Lithuania) to minor changes
(Slovakia, Turkey) and slight decreases (Ireland, Netherlands). We place our results
within the larger context of European forest policy and the challenges of simulating and
contrasting forest biodiversity and the ecosystem services that societies depend oninfo:eu-repo/semantics/publishedVersio
Serotonergic aspects on high consumption of alcohol in humans. Experimental and clinical studies
In animal studies an association between alcohol intake and central serotonergic function has been demonstrated. There are also evidence for altered serotonergic neurotransmission in subgroups of alcohol-dependent subjects.The aim of the thesis was to investigate the effect of SSRIs (selective serotonin reuptake inhibitors) on alcohol intake, in relation to biological markers for alcoholism, in men with long-term high alcohol consumption but without social, psychiatric or somatic complications due to their alcohol intake. The subjects were approximately 50 years old, had a history of daily alcohol consumption of about 100 g since 10 years. Despite that 70% fulfilled DSM-IV criteria for alcohol dependence only 30% had earlier experiences from health care or voluntary organizations due to their alcohol problem. They had few social, medical or other complications related to their alcohol intake. They may therefore represent a group of patients not well known in traditional treatment programs.Compared to a norm group they had lower levels of mental well-being but no anxious or depressive symptoms as assessed by rating scales. The lower moods were most marked in the group of subjects who discontinued the study. Reduction in alcohol consumption of about 60% did not affect moods. Treatment with an SSRI did not increase moods although a trend was observed. On the other hand, participating in the study program increased mood levels to that of a norm group.The subjects were found to have signs of impaired central serotonergic neurotransmission as assessed by the fenfluramine challenge test, but platelet monoamine oxidase B (MAO-B) activity was of the same magnitude as in a reference group. The presence of the dopamine receptor D2 (DRD2) A1 allele was about 20%, as could be expected from the prevalence in the general population. Subjects with the DRD2 A1 allele had lower platelet MAO-B activity than those with the DRD2 A2/A2 alleles.The present studies suggest that treatment with an SSRI during a period of alcohol consumption can reduce alcohol intake by about 20% compared to placebo for at least 2 weeks. This finding is more of a theoretical interest than of clinical usefulness. Predictors for an alcohol-reducing effect of SSRIs may be a mean daily pure alcohol consumption between 60 and 100 g, presence of the DRD2 A2/A2 alleles and high prolactin response to fenfluramine
Teknisk verifiering och validering av ADS-B/VDL Mode 4 för A-SMGCS
This report is a technical verification and validation of ADS-B (Automatic Dependent Surveillance – Broadcast) over VDL Mode 4 (Very High Frequency Data Link Mode 4) for the use in the surveillance element of an A-SMGCS (Advanced Surface Movement Guidance and Control System). The main objective of this report is to examine if ADS-B/VDL Mode 4 fulfils the technical requirements for an implementation at Arlanda airport, Stockholm Sweden. The report also includes a FMECA (Failure Mode, Effects and Criticality Analysis), a theoretical background and methods for monitoring. The process of making this report can be divided into three phases: 1. Preliminary Study. In this phase the requirements were examined and structured. 2. Verification. In this phase the system performance has been verified both theoretically and by several tests at Arlanda Airport. Simulation results have also been used. 3. Validation and documentation. The tests and verifications that were performed in phase 2 were validated in the third phase of the project. The final project document was also written in this phase. The main conclusion from this analysis is that ADS-B/VDL Mode 4 is well suited for surveillance. ADS-B/VDL Mode 4 has the possibility to fulfil all considered requirements, apart from detecting all obstacles. But if all the requirements are going to be fulfilled depends both on the implementation and the operational environment. The results from this verification and validation should be used as the technical subset in a future safety case, both in Sweden and internationally
Histology of uterine leiomyoma and occurrence in relation to reproductive activity in the Baltic gray seal (Halichoerus grypus)
A high prevalence of uterine leiomyoma has been reported in Baltic gray seals aged 15 years and above. Studies on Baltic seals during the 1970s revealed high tissue concentrations of the organochlorines bis(chlorophenyl)-1,1,1-trichloroethane (DDT) and polychlorinated biphenyls (PCBs), lowered reproduction rate, and pathologic changes. In the second half of the 1970s, decreases of PCB and DDT in Baltic biota occurred, and the prevalence of pregnancies in Baltic seals increased. Between 1975 and 1997, 53 Baltic gray seal females of age 15-40 years were found dead and sent to the Swedish Museum of Natural History. Seals were autopsied and 34/53 (64%) had uterine leiomyomas. Samples from 15 were sufficiently well preserved for histologic examination. Uterine leiomyomas were found most commonly in the uterine corpus but also were observed in the uterine horns, cervix, and vagina. Cut surfaces of the leiomyomas appeared as whorled white fibrous tissue. Histologically, spindle cells were arranged in a whorl-like pattern. The nuclei were rod-like and strikingly uniform in shape and size. Mitotic figures were rare. Immunohistochemical staining of the tumors showed a positive reaction to antibodies recognizing smooth muscle actin. Reproductively active gray seals have an ovarian corpus luteum or albicans for most of the year. In 22/34 (65%) gray seals with uterine leiomyomas, ovaries did not contain corpora. In gray seals without macroscopically detected uterine leiomyoma, ovaries from 6/19 (32%) seals had no corpora. It is possible that the development of leiomyoma in the seals is associated with organochlorines and the previous low reproductive activity.</p
Placental dysfunction in Suramin-treated rats : impact of maternal diabetes and effects of antioxidative treatment
OBJECTIVE: The aim of the present study was to evaluate a rat model of placental dysfunction/preeclampsia in pregnancies complicated by maternal diabetes. A second objective was to evaluate the effects of vitamin E treatment in this model. METHODS: Normal and streptozotocin-induced diabetic rats of two different strains (U and H) were given intraperitoneal (IP) injections of the angiogenesis inhibitor Suramin (Sigma Chemical Co, St Louis, MO) or saline in early pregnancy, and fed standard or vitamin E-enriched food. The outcome of pregnancy was evaluated on gestational day 20. RESULTS: In both rat strains Suramin caused fetal growth retardation, decreased placental blood flow, and increased placental concentration of the isoprostane 8-iso-PGF(2alpha). In the U rats Suramin also caused increased fetal resorption rate, increased maternal blood pressure, decreased renal blood flow, and diminished maternal growth. Diabetes caused severe maternal and fetal growth retardation, increased resorption rate, and increased placental 8-iso-PGF(2alpha) concentration independent of Suramin administration. The maternal and fetal effects of Suramin and diabetes were more pronounced in the U strain than in the H strain. Vitamin E treatment improved the status of Suramin-injected diabetic rats: in U rats the blood pressure increase was normalized; and in both U and H rats the decreased placental blood flow was marginally enhanced, and the increase in placental 8-iso-PGF(2alpha) was partly normalized by vitamin E. CONCLUSION: Suramin injections to pregnant rats cause a state of placental insufficiency, which in U rats resembles human preeclampsia. The induction of this condition is at least partly mediated by oxidative stress, and antagonized by antioxidative treatment. Maternal diabetes involves increased oxidative stress, and causes both maternal and fetal morbidity, which are only marginally affected by additional Suramin treatment.</p
Is long-term heavy alcohol consumption toxic for brain serotonergic neurons? Relationship between years of excessive alcohol consumption and serotonergic neurotransmission
The relationship between years of excessive alcohol consumption and central serotonergic neurotransmission, as assessed by the prolactin (PRL) response to D-fenfluramine, was investigated in 22 male alcohol-dependent subjects. A negative correlation was obtained, that is, the longer duration of excessive alcohol consumption the lower PRL response to D-fenfluramine. It is therefore suggested that long duration of excessive alcohol consumption in alcohol-dependent subjects causes a reduction in central serotonergic neurotransmission, possibly by a toxic effect of alcohol on serotonin neurons. The relationship between depressive and anxiety symptoms during on-going drinking and the PRL response to D-fenfluramine was also investigated. No such correlations were obtained, suggesting that reduction in central serotonergic neurotransmission does not pre-dispose to the development of depressive and anxiety symptoms, at least in relation to on-going drinking in alcohol-dependent subjects
Is long-term heavy alcohol consumption toxic for brain serotonergic neurons? Relationship between years of excessive alcohol consumption and serotonergic neurotransmission
The relationship between years of excessive alcohol consumption and central serotonergic neurotransmission, as assessed by the prolactin (PRL) response to D-fenfluramine, was investigated in 22 male alcohol-dependent subjects. A negative correlation was obtained, that is, the longer duration of excessive alcohol consumption the lower PRL response to D-fenfluramine. It is therefore suggested that long duration of excessive alcohol consumption in alcohol-dependent subjects causes a reduction in central serotonergic neurotransmission, possibly by a toxic effect of alcohol on serotonin neurons. The relationship between depressive and anxiety symptoms during on-going drinking and the PRL response to D-fenfluramine was also investigated. No such correlations were obtained, suggesting that reduction in central serotonergic neurotransmission does not pre-dispose to the development of depressive and anxiety symptoms, at least in relation to on-going drinking in alcohol-dependent subjects
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