1 |
Species diversity, habitat utilization and blood parasites of amphibians in and around Ndumo Game Reserve / Edward Charles NetherlandsNetherlands, Edward Charles January 2014 (has links)
Ndumo
Game
Reserve
is
the
only
officially
protected
area
within
the
Phongolo
Floodplain;
an
area
in
the
northern
parts
of
KwaZulu-‐Natal
known
to
boast
a
rich
diversity
of
amphibians,
thus
becoming
one
of
the
focal
areas
for
this
study.
The
study’s
aim
was
to
monitor
and
record
amphibian
diversity,
as
well
as
associated
blood
parasite
biodiversity.
For
the
purpose
of
monitoring,
a
number
of
active
and
passive
techniques
were
employed.
Habitat
preferences
for
the
expected
species
were
divided
into
five
types,
namely
endorheic,
lacustrine,
palustrine,
riverine
and
terrestrial.
Endorheic
habitats
were
found
to
harbour
the
highest
diversity
(70%)
of
frog
species.
A
permanent
song
meter
was
used
to
passively
record
calling
activity
of
frog
species
associated
with
endorheic
systems.
This
call
data
indicated
peak
breeding
season,
preferred
calling
times
and
intensities
of
the
different
species.
Historical
records
from
the
same
area
were
used
as
a
basis
to
which
this
study’s
data
were
compared.
In
the
case
of
the
polychromatic
Argus
Reed
Frog
Hyperolius
argus
Peters,
1854,
questions
were
raised
concerning
the
major
colour
changes
during
development
of
the
apparent
sub-‐adult
to
adult
life
stages,
an
observation
which
was
has
caused
some
confusion
as
to
whether
these
forms
represented
a
single
species
or
multiple
cryptic
species.
These
issues
were
clarified
using
techniques
such
as
DNA
extraction
and
polymerase
chain
reaction
(PCR).
Furthermore,
a
blood
parasite
survey
was
conducted.
Thin
blood
smears
for
morphometrics
and
whole
blood
for
molecular
work,
were
collected
from
29
species
and
436
individual
frogs.
For
the
majority
of
the
recorded
parasites,
techniques
such
as
light
microscopy
were
utilized
for
the
morphological
description
and
classification
of
these
parasites.
Among
the
recorded
frog
blood
parasites
observed,
20%
of
the
frog
specimens
were
infected
with
at
least
one
blood
parasite
group.
Hepatozoon
and
Trypanosoma
species
accounted
for
most
of
the
infections;
the
former
demonstrated
significant
differences
in
intensity
of
infection
across
species,
families
and
habitat
types
(P
=
0.028;
P
=
0.006;
P
=
0.007
respectively).
Methods,
such
as
transmission
electron
microscopy,
examining
the
ultrastructure,
as
well
as
parasite
DNA
extraction
and
18S
rDNA
gene
sequences
for
the
molecular
and
phylogenetic
characterization,
were
reserved
for
Hepatozoon
species
infecting
common
toad
species
(Amietophrynus).
Parasite
stages
observed
were
measured
and
compared
to
each
other,
as
well
as
to
other
described
African
bufonid
haemogregarines.
Resulting
sequences
were
compared
with
each
other
and
to
comparative
haemogregarine
sequences
selected
from
GenBank.
In
the
current
study
a
number
of
important
aspects
with
regards
to
monitoring
and
assessment
of
amphibians
in
their
natural
environment
were
explored,
including
looking
at
and
determining
diversity
and
prevalence
of
blood
parasites.
Furthermore,
important
data
on
gaining
a
better
understanding
of
amphibians
and
their
behavioural
activities
were
also
gathered,
which
should
be
able
to
assist
in
conservation
actions
to
effectively
protect
South
African
anurans
and
their
required
habitat
types. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
|
2 |
Species diversity, habitat utilization and blood parasites of amphibians in and around Ndumo Game Reserve / Edward Charles NetherlandsNetherlands, Edward Charles January 2014 (has links)
Ndumo
Game
Reserve
is
the
only
officially
protected
area
within
the
Phongolo
Floodplain;
an
area
in
the
northern
parts
of
KwaZulu-‐Natal
known
to
boast
a
rich
diversity
of
amphibians,
thus
becoming
one
of
the
focal
areas
for
this
study.
The
study’s
aim
was
to
monitor
and
record
amphibian
diversity,
as
well
as
associated
blood
parasite
biodiversity.
For
the
purpose
of
monitoring,
a
number
of
active
and
passive
techniques
were
employed.
Habitat
preferences
for
the
expected
species
were
divided
into
five
types,
namely
endorheic,
lacustrine,
palustrine,
riverine
and
terrestrial.
Endorheic
habitats
were
found
to
harbour
the
highest
diversity
(70%)
of
frog
species.
A
permanent
song
meter
was
used
to
passively
record
calling
activity
of
frog
species
associated
with
endorheic
systems.
This
call
data
indicated
peak
breeding
season,
preferred
calling
times
and
intensities
of
the
different
species.
Historical
records
from
the
same
area
were
used
as
a
basis
to
which
this
study’s
data
were
compared.
In
the
case
of
the
polychromatic
Argus
Reed
Frog
Hyperolius
argus
Peters,
1854,
questions
were
raised
concerning
the
major
colour
changes
during
development
of
the
apparent
sub-‐adult
to
adult
life
stages,
an
observation
which
was
has
caused
some
confusion
as
to
whether
these
forms
represented
a
single
species
or
multiple
cryptic
species.
These
issues
were
clarified
using
techniques
such
as
DNA
extraction
and
polymerase
chain
reaction
(PCR).
Furthermore,
a
blood
parasite
survey
was
conducted.
Thin
blood
smears
for
morphometrics
and
whole
blood
for
molecular
work,
were
collected
from
29
species
and
436
individual
frogs.
For
the
majority
of
the
recorded
parasites,
techniques
such
as
light
microscopy
were
utilized
for
the
morphological
description
and
classification
of
these
parasites.
Among
the
recorded
frog
blood
parasites
observed,
20%
of
the
frog
specimens
were
infected
with
at
least
one
blood
parasite
group.
Hepatozoon
and
Trypanosoma
species
accounted
for
most
of
the
infections;
the
former
demonstrated
significant
differences
in
intensity
of
infection
across
species,
families
and
habitat
types
(P
=
0.028;
P
=
0.006;
P
=
0.007
respectively).
Methods,
such
as
transmission
electron
microscopy,
examining
the
ultrastructure,
as
well
as
parasite
DNA
extraction
and
18S
rDNA
gene
sequences
for
the
molecular
and
phylogenetic
characterization,
were
reserved
for
Hepatozoon
species
infecting
common
toad
species
(Amietophrynus).
Parasite
stages
observed
were
measured
and
compared
to
each
other,
as
well
as
to
other
described
African
bufonid
haemogregarines.
Resulting
sequences
were
compared
with
each
other
and
to
comparative
haemogregarine
sequences
selected
from
GenBank.
In
the
current
study
a
number
of
important
aspects
with
regards
to
monitoring
and
assessment
of
amphibians
in
their
natural
environment
were
explored,
including
looking
at
and
determining
diversity
and
prevalence
of
blood
parasites.
Furthermore,
important
data
on
gaining
a
better
understanding
of
amphibians
and
their
behavioural
activities
were
also
gathered,
which
should
be
able
to
assist
in
conservation
actions
to
effectively
protect
South
African
anurans
and
their
required
habitat
types. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
|
3 |
Polychromatic determination of spectral response of PV devicesSara, Ira D. January 2014 (has links)
This thesis introduces a novel spectral response (SR) measurement technique using polychromatic filters (filters with very broad spectral transmittances) to determine SR of large area PV devices. Conventionally, SR of a photovoltaic (PV) device is determined by illuminating the device under test (DUT) with a series of monochromatic beams at different wavelengths as described in the international standard IEC 60904-8, or beams of limited spectral content using narrow band pass filters or monochromator. One significant problem associated with the application of the narrow band pass filters for a large-area SR measurement is that low light intensity produced on the measurement plane particularly in certain wavelength ranges: the ultraviolet and infrared. This can produce weak signal responses from a tested PV device. In addition, the imperfection of the filter s mounting position can shift the peak wavelength of the filter s transmittance at angle of incidence greater than 10°. This can cause stray light on the measurement plane. The proposed SR measurement method is called the 'polychromatic SR fitting method' or, in short, it is known as the 'polychromatic method'. The advantage of this method is that higher beam intensity can be produced on the measurement plane as a result of large spectral transmittance of the polychromatic filters. This can improve the signal strength of a tested PV device. This new SR measurement method works by comparing the variations in the currents which are measured at different spectra to the currents which are calculated at the same spectral conditions using the SR model. Validations of this method for a large- and small-area SR determinations show that it is potentially feasible as a new technique for determining SR of a PV device with deviations within ±2% across the wavelength bands.
|
4 |
Development of a Fast X-ray Line Detector System for Two-Phase Flow MeasurementSong, Kyle 21 December 2016 (has links)
Measuring void fraction distribution in two-phase flow has been a challenging task for many decades because of its complex and fast-changing interfacial structure. In this study, a non-intrusive X-ray measurement system is developed and calibrated to mitigate this challenge. This approach has several advantages over the conventional methods such as the multi-sensor conductivity probe, wire-mesh sensor, impedance void meter, or direct optical imaging. The X-ray densitometry technique is non-intrusive, insensitive to flow regime changes, capable of measuring high temperature or high-pressure flows, and has reasonable penetration depth. With the advancement of detector technology, the system developed in this work can further achieve high spatial resolution (100 micron per pixel) and high temporal resolution (1000 frames per second). This work mainly focuses on the following aspects of the system development: establishing a geometrical model for the line detector system, conducting spectral analysis for X-ray attenuation in two-phase flow, and performing calibration tests. The geometrical model has considered the measurement plane, geometry of the test-section wall and flow channel, relative position of the X-ray source and detector pixels. By assuming axisymmetry, an algorithm has been developed to convert void fraction distribution along the detector pixels to the radial void profile in a circular pipe. The X-ray spectral analysis yielded a novel prediction model for non-chromatic X-rays and non-uniform structure materials such as the internal two-phase flow which contains gas, liquid and solid wall materials. A calibration experiment has been carried out to optimize the detector conversion factor for each detector pixels. Finally, the data measured by the developed X-ray system are compared with the double-sensor conductivity probe and gas flow meter for sample bubbly flow and slug flow conditions. The results show reasonable agreement between these different measuring techniques. / Master of Science
|
5 |
Imunofenotypové rozdíly v B lymfocytárních populacích non-memory B lymfocytů u zdravých kontrol a pacientů s imunopatologiemi. / Immunophenotype differences in non-memory B lymphocyte populations in healthy controls and patients with immunopathologiesPolák, Milan January 2014 (has links)
B-lymphocytes are a subset of immune cells that can be distinguished mainly by carrying clonally diversified membrane-bound immunoglobulin specialized to specific antigen recognition. Together with other immunocytes B-lymphocytes play a central role in adaptive immune system which takes part in defense of the host against wide variety of pathogens. Recently the evidence has supported the emerging concept of different B-cell subpopulations to play a direct or indirect role in a pathogenesis of spectrum of disorders. However, so far the knowledge has been limited mainly in the way of how the specific differentiation stages of B-lymphocytes are involved in pathogenesis of diseases and how course of disease, stage, and eventually different treatment can affect B-cell homeostasis. That is the reason for the thesis to be focused on an analysis of B-cell population profile changes in disease, identification of any association present among specific B-cell subpopulations, as well as association between these subpopulations and clinical parameters. Using polychromatic flow cytometry we analyzed frequencies of 11 B-cell subpopulations including stages of transient B-lymphocytes through effector antibody-producing plasma cells. We examined 81 individuals including 22 healthy controls and 59 patients with...
|
6 |
Hydrodynamic Modelling for a Point Absorbing Wave Energy ConverterEngström, Jens January 2011 (has links)
Surface gravity waves in the world’s oceans contain a renewable source of free power on the order of terawatts that has to this date not been commercially utilized. The division of Electricity at Uppsala University is developing a technology to harvest this energy. The technology is a point absorber type wave energy converter based on a direct-driven linear generator placed on the sea bed connected via a line to a buoy on the surface. The work in this thesis is focused mainly on the energy transport of ocean waves and on increasing the transfer of energy from the waves to the generator and load. Potential linear wave theory is used to describe the ocean waves and to derive the hydrodynamic forces that are exerted on the buoy. Expressions for the energy transport in polychromatic waves travelling over waters of finite depth are derived and extracted from measured time series of wave elevation collected at the Lysekil test site. The results are compared to existing solutions that uses the simpler deep water approximation. A Two-Body system wave energy converter model tuned to resonance in Swedish west coast sea states is developed based on the Lysekil project concept. The first indicative results are derived by using a linear resistive load. The concept is further extended by a coupled hydrodynamic and electromagnetic model with two more realistic non-linear load conditions. Results show that the use of the deep water approximation gives a too low energy transport in the time averaged as well as in the total instantaneous energy transport. Around the resonance frequency, a Two-Body System gives a power capture ratio of up to 80 percent. For more energetic sea states the power capture ratio decreases rapidly, indicating a smoother power output. The currents in the generator when using the Two-Body system is shown to be more evenly distributed compared to the conventional system, indicating a better utilization of the electrical equipment. Although the resonant nature of the system makes it sensitive to the shape of the wave spectrum, results indicate a threefold increase in annual power production compared to the conventional system.
|
7 |
Imunotypové rozdíly v subpopulacích CD27+ B lymfocytů u zdravých kontrol a pacientů s různými imunopatologiemi / Differences in immunophenotype of CD27+ B lymphocyte subpopulations in healthy controls and patients with various immunopathologiesValatová, Pavla January 2016 (has links)
The immune system will maintain the integrity of the organism from harmful non-malicious recognizes and protects the body against exo- and endogenous toxic substances and together with the nervous and endocrine system are among regulatory systems of the organism. Recently the evidence has supported the emerging concept of different B cell subpopulations to play a direct or indirect role in a pathogenesis of spectrum of disorders. However, so far the knowledge has been limited mainly in the way of how the specific differentiation stages of B lymphocytes are involved in pathogenesis of diseases and how course of disease, stage, and eventually different treatment can affect B cell homeostasis. This work is focused on the study of peripheral CD27+ B lymphocytes (one of the least explored human B lymphocytes) in healthy controls and patients with various immunopathologies, in this case we present representative results for patients with inflammatory bowel disease. Using polychromatic flow cytometry we examined 31 of peripheral blood samples, including 14 controls, 7 patients with Crohn's disease (CD) and 5 with ulcerative colitis (UC). In 6 patients with CD, we were able to perform immunophenotyping also 2 hours after intravenous administration of infliximab, and in one patient 14 days after drug...
|
8 |
Polar-Plane-Free Faceted InGaN-LEDs toward Highly Radiative Polychromatic Emitters / 高効率多色発光素子に向けた極性面フリーなマルチファセットInGaN-LEDに関する研究Matsuda, Yoshinobu 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22449号 / 工博第4710号 / 新制||工||1736(附属図書館) / 京都大学大学院工学研究科電子工学専攻 / (主査)教授 川上 養一, 教授 野田 進, 教授 山田 啓文 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
|
9 |
Hormetic UV treatments for control of plant diseases on protected edible cropsScott, George January 2017 (has links)
Hormesis is a dose response phenomenon where low doses of a stress bring about a positive response in the organism undergoing treatment. UV-C hormesis has been known for over three decades and has a broad range of benefits on postharvest produce. Benefits include increased nutritional content, delayed chlorophyll degradation and disease resistance. The beneficial effects have been observed on many varieties of fresh produce including climacteric and non-climacteric fruit, tubers, salads and brassicas. The majority of previous studies have used low-intensity (LIUV) UV-C sources. LIUV sources require lengthy treatment times, which are in the region of 6 minutes for tomato fruit. This has, in part, prevented the commercial application of this technique. High-intensity, pulsed polychromatic light (HIPPL) sources, however, have recently been developed. HIPPL sources may have the potential to drastically reduce treatment times and increase their commercial viability. It was shown, here, that the use of HIPPL can control disease (reduce disease progression) caused by Botrytis cinerea and Penicillium expansum and also delay ripening on tomato fruit. Both disease control and delayed ripening were at similar levels for LIUV and HIPPL treatments on mature green fruit. The HIPPL treatments used in these studies can reduce treatment times for tomato fruit by 97.3%. Both HIPPL and LIUV treatments elicit local responses irrespective of the treatment orientation and tomato fruit, therefore, require full surface irradiation. Furthermore, UV-C in the HIPPL source is not required for disease control or delayed ripening. It does, however, contribute approximately 50% towards the total observed effects. Investigations into the mechanisms underpinning postharvest HIPPL and LIUV hormesis, on tomato fruit, identified that the expression of genes involved in plant hormone biosynthesis, defence, secondary metabolism and ripening were affected. This indicates that disease control is achieved through induced resistance. Changes to expression, following treatment, were highly similar for both HIPPL and LIUV treatments and were mediated by salicylic acid, jasmonic acid and ethylene. This may lead to broad range resistance against necrotrophic and biotrophic pathogens as well as abiotic stresses and herbivorous pests. Recently, the exposure of foliage to UV-C has been shown to induce resistance against B. cinerea on Arabidopsis thaliana. The horticultural applications of such treatments, however, have not been explored. Pre-harvest treatments of lettuce in the glasshouse showed variation in damage threshold and optimal treatment to control disease following LIUV and HIPPL treatment. Further sources of variation included the cultivar, pathogen of interest and the point that treatment was applied during the year. Using a controlled environment allowed seasonal variation to be mitigated and both HIPPL and LIUV treatments controlled disease against B. cinerea. For pre-harvest treatments to be a success in the glasshouse, further studies into how both biotic and abiotic factors influence treatment is required. To circumvent the problems associated with pre-harvest treatments and environmental variation in the glasshouse, LIUV seed treatments were performed on tomato. Control of B. cinerea was established with an approximately 10% reduction in incidence and disease progression with a 4 kJ/m2 treatment. When monitoring the effect of treatment on germination and early seedling development it was also identified that an 8 kJ/m2 treatment led to biostimulation of germination and root and shoot growth.
|
10 |
Změny v distribuci subpopulací B lymfocytů u pacientů s Crohnovou chorobou před a po biologické léčbě / Changes in distribution of B lymphocyte subpopulations in patients with Crohn disease before and after biological therapySuchá, Renata January 2016 (has links)
B-lymphocytes are lymphoid cells, which are a part of the adaptive/innate immune system and generate antibodies. Recently, many studies have supported hypothesis that different rather minor B-lymphocyte subpopulations may play a direct and indirect role in immunopathogenesis in human pathologies such as Crohn's disease (CD). The aim of current study was therefore to investigate distribution of frequencies of B lymphocyte subpopulations (from transient to mature effector B cell stages) in peripheral blood of healthy subjects (CO), patients with Crohn's disease (CD) and ulcerative colitis (UC). Thus, using 11-colour flow cytometry we have analysed 30 blood samples of individuals, including 14 healthy controls, 11 patients with Crohn's disease and 5 with UC. In 6 patients with CD we have had an opportunity to analyze blood samples collected 2 hours after an administration of anti-TNF therapy. Higher frequencies of memory B-lymphocytes (CD19+ CD27+ , CD19+ CD20+ CD27+ and CD19+ CD20+ CD27+ IgM+) were found in patients with CD as compared to COs. (20.06±13.58%; 17.61±13.48%; 88.60±20.56% vs. 11.75±26.47%; 11.25±26.50%; and 66.82±22.60%), in case of CD19+CD20-CD27-IgM+ B-lymphocytes the difference was statistically significant (57.15±17.21% in CD vs. 19.59±31.79% in CO; p=0.0341), which is in accordance...
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