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81 Uppsatser om Organochlorine compounds - Sida 4 av 6
Återföring av växtnäringsämnen från avloppsvatten till åkermark : en bedömning av intresset för nya näringsrika produkter
Sewage sludge contains plant nutrients and has earlier been utilised as fertilizer to cropland. Unfortunately not only plant nutrients but also heavy metals, pathogens and organic contaminants tend to accumulate in sludge. The suitability to use sewage sludge in agriculture has therefore been subject to several discussions over the years. The Swedish food industry does no longer accept sludge as fertiliser for Swedish producers.
In 1999 the Swedish parliament accepted several objectives for environmental protection. In order to prevent environmental pollution and further exploitation of the earth crust, one of these objectives confirm that phosphorous from sewage shall be recirculated to arable land.
Kan D-vitamintillskott minska depressiva symtom?
Background: Sweden is a country where vitamin D deficiency seems to be common, partly because of its geographical position, which reduces the availability of UVB radiation, but also that people avoid sunlight due to increased skin cancer risk. Research shows that vitamin D plays an important role in the prevention of many diseases such as cancer as well as autoimmune and neuropsychiatric diseases.Vitamin D is a fat soluble pre-hormone and a collective name for closely related compounds which act as hormones after undergoing a transformation in the body.Humans can utilize vitamin D through diet and produce it in the body by exposing the skin to the sun. Previous observational studies and epidemiological studies have established a hypothesis that there seems to be an association between vitamin D supplementation and reduction of depressive symptoms.Objective: The aim of this study was to investigate if vitamin D supplements may decrease depressive symptoms.Methods: This work is organized as a literature review and article search is made in the database PubMed in January 2012. Keywords used were ?vitamin D and depression? and inclusion criteria were: randomized clinical trials, be conducted on humans, written in English.
Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)
Peat lands are a great potential resource for increased forest growth in Sweden, there are approximately 6.5 million hectares of peat lands, whereof around 70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste land. There are over 200 000 hectares of peat land that is already drained and wooded, and that may be suitable for fertilization. Forest production on peat soils usually requires drainage and fertilization. Dewatering requires ditching the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The purpose of this work was to examine the effects of potassium fertilization on the growth of spruces that were planted on drained peat land and how different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance transport in the tree. Potassium is also important for the carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter resistance of many species. Potassium is not found in any organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was left without fertilization. All plots that were fertilized with potassium grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality estimation of wetlands after ditching (dikningsbonitering). The plot with most potassium produced after fertilizationaproximately in level with theoretical estimations. Key words: Peat land, Fertilization, Ditching, Growth, site quality..
Är den starkt växande vildsvinspopulationen ett hot mot tjäderns reden?
This case study is based on a previous documented method of manufacturing artificial nest containing pre-colored hen eggs. This method is going to be used to find, if the wild boar population, which is growing in number, is a threat to the capercaillie population. In comparison to the wild boar population, the capercaillie population is diminishing in different parts of Sweden. In order to find out if they are affect by each other, the case study was carried out during the months of April to May 2009. 100 artificial nests were placed out on various locations on the Södertuna estate just in the outskirts of Gnesta. The unique aspect of this study is that a fenced environment to keep out wild animals is used to conduct this study, which has been previously known to be free from wild boar, but the area outside has sittings of wild boar. So to fully understand how this affects the capercaillie population, 50 of the nests were placed outside the fence area, while the other 50 nests were placed inside the fenced area. The sites were visited on two separate occasions, and were noted of the changes inside and outside the fenced compounds.
Fermentation of lignocellulosic material by the alternative industrial ethanol yeast Dekkera bruxellensis
Bioethanol is one alternative energy fuel that can be produced from different types of biomass. Second generation bioethanol comes from fermentation of lignocellulosic material and can be seen as a more environmental friendly alternative as e.g. forest residues and agricultural by-products are used. To be able to use lignocellulosic biomass in ethanol production, it has to be subjected to different treatments first. In this study, aspen sawdust was used as lignocellulosic material.
Smaksatt vodka : En sensorisk analys av konsumenters preferenser
InledningÅr 1879, grundade Lars Olsson Smith Absolut rent brännvin, dåtidens Absolut Vodka. År 1979,hundra år senare passerade företaget en ny fas genom globalisering under varumärket AbsolutVodka. Sedan introduktionen av det nya varumärket har försäljningen stigit från 0,1 miljoner litertill 96,6 miljoner liter per år, över hela värden. Under senare delen av 1980-talet introduceradeföretaget smaksatta vodkasorter för att främja barbranschens cocktails.Syfte och frågeställningUppsatsens syfte är att kartlägga hur konsumenter upplever intensiteten på fem utvaldasmakegenskaper i smaksatt vodka, satt i relation till hur de egentligen önskar att intensiteten skullevara.Uppfyller Absolut Vodkas smaksatta vodkor konsumenternas preferenser?Metod och materialUndersökningen grundar sig i en sensorisk analys för att besvara uppsatsens syfte ochfrågeställning.
Patologiska förändringar och säsongsmässiga variationer i testiklar från svenska brunbjörnar (Ursus arctos) :
Functioning reproductive organs are essential for the survival of a species. The reproductive system is very sensitive to exposure of chemical substances of anthropogenic origin. Humans release great amounts of chemical substances to the environment by our means of life and these substances have been proved to have a negative effect on the reproductive ability of different vertebral classes. In the polar bear (Ursus maritimus) a declined reproductive ability as an effect of decreased testosterone levels and decreased testicular size has been connected to the presence of high levels of organohalogenic compounds like PCBs. Although the Swedish brown bear (Ursus arctos) is not as carnivorous as its close relative the polar bear it is still exposed to environmental.
Energy efficient storage of biomass at Vattenfall heat and power plants
Storage of biomass is often associated with problems such as heat development, dry
matter losses and reduction of fuel quality. The rise in temperature can potentially
cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles
can cause health problems in the surrounding. The dry matter losses and reduction of
fuel quality can have economical effects. The aim of this thesis project is to develop
guidelines on how to store large amount of biomass at Vattenfalls heat and power
plants in an optimal way.
Perioperativ omvårdnad vid kejsarsnitt hos tik ? förbättra utfall för tik och valpar
Dystocia, or difficult birth, is a commonly seen complication to natural birth in veterinary hospitals. Although other methods of resolving dystocia exist, 60 % of dystocias will need to undergo caesarean section. To perform a caesarean section, the bitch will have to undergo anesthesia.
The purpose of this literary study was to provide a deeper understanding regarding how the physiologic changes that occur during pregnancy influence anesthetic management in the bitch and puppies. Which anesthetic drugs and drug combinations indicated was also investigated as well as how a veterinary nurse can optimize care of the mother throughout the procedure and how resuscitation of the puppies should be carried out for best possible outcome.
Anestesi vid kastration av spädgris :
An overwhelming majority of all male piglets are castrated without anaesthesia
when they are very young. In Sweden this means that approximately one and a half
million piglets are castrated every year. The reason the piglets are castrated is the
strong and unpleasant smell and taste, the ?boar taint? that the meat from intact
boars sometimes exhibits. Boar taint is chiefly cause by androstenone and skatole,
two compounds that are mostly produced by sexually mature boars and are
accumulated in the subcutaneous fat.
Olfactory responses of the parasitic wasp, Trybliographa rapae (Hymenoptera: Figitidae)
Delia flies (Diptera: Anthomyiidae) are economically important pests in several horticultural crops. The control is commonly relying on chemical insecticides, though there are possibilities with biological control from the natural enemies in the field. An important natural enemy is the parasitic wasp, Trybliographa rapae Westwood (Hymenoptera: Figitidae) that lays eggs in the Delia fly larvae. The parasitoid larva and the host larva have a parallel development until the host dies within its puparium and an adult parasitoid emerges.
The aim of this thesis was to understand the attraction to host- and food-associated plant volatiles of T. rapae, in order to enhance the effectiveness of the parasitic wasp as a biological control agent.
Kvalitetssäkring av hushållsnära avloppsfraktioner : vad kräver livsmedelsbranschen?
On-site sewage systems are common on the countryside of Sweden with approximately one million on-site systems installed. Due to insufficient function, these contribute significantly to the total discharge of phosphorus to rivers and lakes, causing eutrophication.
In order to reduce eutrophication and to fulfil one of the environmental quality objectives, the decision was taken by the Swedish Government in 2005 that 60 % of phosphorous in sewage sludge is to be recycled to arable land before 2015. To make recycling a reality, new solutions have to be found. Federation of Swedish Farmers (LRF) takes an active interest in this issue and has initiated this study.
One problem is that the food industry is sceptical towards recirculation due to the risks that products from sewage systems may contain pathogens, heavy metals and unwanted chemical compounds, e.g.
Antibiotic resistance associated with bacteria in irrigation water : a case study of irrigation ponds in Southern Sweden
The
focus
of
this
project
was
to
characterize
the
occurrence
of
ESBL-?producing
bacteria
in
two
irrigation
water
ponds
in
Southern
Sweden.
Samples
were
taken
from
two
ponds
nearby
each
other,
from
which
analyses
were
made
based
on
levels
of
community
and
individual
isolates.
Community
samples
were
used
for
attempts
for
characterization
of
resistance
patterns
in
irrigation
water
using
the
Omnilog
PM-?plate
system.
The
growth
of
community
microbiota
in
the
presence
of
the
following
antibiotic
substances
was
assessed;
amikacin,
gentamicin,
kanamycin,
penicillin
G,
ampicillin,
piperacillin,
trimethoprim,
potassium
tellurite
and
ciprofloxacin.
Isolates
were
pure
cultured
using
semi-?selective
media:
LB,
Rainbow
Agar,
mEnterococcus,
0.1
TSA
and
VRBD.
A
total
of
177
isolates
were
isolated
randomly.
Each
isolate
was
identified
using
the
Omnilog
GENIII-?system
of
biochemical
characterization.
Further,
the
isolates
were
tested
on
Brilliance
ESBL-?agar
for
their
ability
to
grow.
Out
of
the
total
number
of
isolates,
30
were
selected,
preferably
Enterobacteriaceae
or
Pseudomonas
spp.,
based
on
their
high
similarity
to
library
strain
during
the
identification
in
the
Omnilog-?system.
These
were
further
characterized
using
Etest-?sticks.
Three
selected
strains
were
picked
for
further
analyses
using
exogenous
isolation
for
attempts
to
simulate
horizontal
gene
transfer,
and
Omnilog
PM-?panels
containing
various
antibiotics
of
interest.
Selections
of
samples
were
chosen
for
molecular
tests
targeting
plasmid-?borne
resistance
genes
CTX-?M1,
CTX-?M2
and
SHV.
The
method
for
assessing
community-?resistance
patterns
showed
ambiguous
data
that
was
difficult
to
interpret;
further
optimization
is
recommended.
For
all
tested
PM-?plates,
generally
greatest
differences
between
substances
were
found
among
wells
with
the
strongest
concentration
of
antibiotic
substance.
A
total
of
175
isolates
displayed
ability
to
grow
on
ESBL-?agar.
Etests
confirmed
ability
of
isolates
to
resist
many
?-?lactam
antibiotics
and
many
were
clinically
resistant
to
certain
substances.
No
plasmids
were
transferred
during
exogenous
isolation.
During
molecular
tests,
a
few
matches
were
found
for
the
CTX-?M1
gene.
Isolates
analyzed
with
Omnilog
PM-?plates
showed
resistance
to
most
compounds
tested.
The
isolates
showed
greatest
resistance
toward
penicillin
G,
ampicillin,
amikacin,
kanamycin
and
trimethoprim.
In
the
study,
it
was
established
that
resistance
among
bacteria
was
frequently
occurring
in
the
irrigation
water,
and
?-?lactamase
producing
bacteria
was
very
common.
Extended
studies
are
needed
to
assess
the
frequency-?
and
occurrence
of
horizontal
gene
transfer
(HGF)
in
this
environment.
Although
some
potential
corresponding
data
is
found,
it
is
at
this
point
not
possible
to
determine
whether
the
resistances
are
due
to
antibiotics
used
in
veterinary
medicine,
human
medicine
or
one
additional
reason
is
travel
and
trade.
in
irrigation
water
using
the
Omnilog
PM-?plate
system.
The
growth
of
community
microbiota
in
the
presence
of
the
following
antibiotic
substances
was
assessed;
amikacin,
gentamicin,
kanamycin,
penicillin
G,
ampicillin,
piperacillin,
trimethoprim,
potassium
tellurite
and
ciprofloxacin.
Isolates
were
pure
cultured
using
semi-?selective
media:
LB,
Rainbow
Agar,
mEnterococcus,
0.1
TSA
and
VRBD.
A
total
of
177
isolates
were
isolated
randomly.
Each
isolate
was
identified
using
the
Omnilog
GENIII-?system
of
biochemical
characterization.
Further,
the
isolates
were
tested
on
Brilliance
ESBL-?agar
for
their
ability
to
grow.
Out
of
the
total
number
of
isolates,
30
were
selected,
preferably
Enterobacteriaceae
or
Pseudomonas
spp.,
based
on
their
high
similarity
to
library
strain
during
the
identification
in
the
Omnilog-?system.
These
were
further
characterized
using
Etest-?sticks.
Three
selected
strains
were
picked
for
further
analyses
using
exogenous
isolation
for
attempts
to
simulate
horizontal
gene
transfer,
and
Omnilog
PM-?panels
containing
various
antibiotics
of
interest.
Selections
of
samples
were
chosen
for
molecular
tests
targeting
plasmid-?borne
resistance
genes
CTX-?M1,
CTX-?M2
and
SHV.
The
method
for
assessing
community-?resistance
patterns
showed
ambiguous
data
that
was
difficult
to
interpret;
further
optimization
is
recommended.
For
all
tested
PM-?plates,
generally
greatest
differences
between
substances
were
found
among
wells
with
the
strongest
concentration
of
antibiotic
substance.
A
total
of
175
isolates
displayed
ability
to
grow
on
ESBL-?agar.
Etests
confirmed
ability
of
isolates
to
resist
many
?-?lactam
antibiotics
and
many
were
clinically
resistant
to
certain
substances.
No
plasmids
were
transferred
during
exogenous
isolation.
During
molecular
tests,
a
few
matches
were
found
for
the
CTX-?M1
gene.
Isolates
analyzed
with
Omnilog
PM-?plates
showed
resistance
to
most
compounds
tested.
The
isolates
showed
greatest
resistance
toward
penicillin
G,
ampicillin,
amikacin,
kanamycin
and
trimethoprim.
In
the
study,
it
was
established
that
resistance
among
bacteria
was
frequently
occurring
in
the
irrigation
water,
and
?-?lactamase
producing
bacteria
was
very
common.
Extended
studies
are
needed
to
assess
the
frequency-?
and
occurrence
of
horizontal
gene
transfer
(HGF)
in
this
environment.
Although
some
potential
corresponding
data
is
found,
it
is
at
this
point
not
possible
to
determine
whether
the
resistances
are
due
to
antibiotics
used
in
veterinary
medicine,
human
medicine
or
one
additional
reason
is
travel
and
trade..
Rostfärgat slam i dränagesystem vid vattenkraftsanläggningar : orsaker och åtgärder
From embankment dams is something that has long been noticed and given rise to different questions. The most serious question is if the sludge is a result of inner erosion through the dam, and thus consists of material transported from the dam. Concerns have also been raised whether the sludge could interfere with the systems drainage capacity and thereby lead to high pore pressure in the dam, or if the measurement of seepage is disturbed, as the measuring is usually made via Thomson weirs, which could risk being blocked.
The result of this investigation shows that the sludge is a result of the oxidation of iron by iron bacteria, and to the greater part consists of these oxides as well as the bacteria?s own structures. The iron oxidizing bacteria, FeOB, oxides ferrous iron to ferric as a part of their metabolism, and thereby create large quantities of iron(oxy)hydroxides.
Tungmetaller i lakvatten : avskiljning med mineraliska filtermaterial
Four different kinds of filter-materials with reactive surfaces have been studied concerning their capacity to absorb heavy metals in leachate from a municipal waste deposit. The heavy metals studied were: lead, cadmium, copper, mercury, chromium, nickel and zinc. The leachate contains high levels of dissolved organic carbon (DOC) and has a high pH-value along with a high buffer capacity. These characteristics of the leachate make it difficult to remove pollutants and require efficient filters. The filters that were examined in the report are blast-furnace slag with CaO, sand covered with iron oxides, olivine and nepheline.