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"Åh! Ett hemligt tal!" : En kvalitativ studie av yngre elevers resonemang vid problemlösning i matematikNyqvist, Marie January 2011 (has links)
Syftet med detta examensarbete var att undersöka om det kan finnas ett samband mellan den språkliga utformningen av en matematisk problemuppgift och elevers val av resonemang. Två grupper av elever fick arbeta med varsin matematisk uppgift med likadant innehåll men olika språklig utformning. Om det fanns skillnader i elevernas val av resonemang mellan de båda uppgifterna så kunde det indikera att det kan finnas ett samband mellan den språkliga utformningen av en matematisk problemuppgift och elevernas val av resonemang. Jag valde att arbeta med två kvalitativa metoder som i min undersökning kompletterade varandra, observation och intervju. Resultatet av undersökningen visar på ett mycket svagt samband mellan den språkliga utformningen och elevernas val av resonemang. Istället väcker resultatet nya frågor om språkets betydelse vid inlärning i matematik.
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The Role of Caveolae in the Loss of ERK2 Activation in Stretched Skeletal MyotubesBellott, Anne Claire 12 July 2004 (has links)
Skeletal muscle function is important to the human body for daily activities. Mechanical signals are critical to the maintenance of that function. Muscle diseases, such as the muscular dystrophies, in which the force transmission apparatus is compromised, have devastating effects on muscle function and quality of life. Mechanical signals activate intracellular signaling to maintain function. ERK2 has been shown to be quickly and strongly upregulated following stretch, leading to cell proliferation. Stretch has been shown to cause deformation of caveolae, invaginations of the plasma membrane that inhibit ERK signaling. This leads to the hypothesis that stretch induced deformation of caveolae may initiate mechanotransduction by activating ERK2. Reducing caveolin-3 expression via siRNA knockdown eradicated the stretch-induced effect on ERK2 activation, indicating that caveolin is required for the stretch response. Stabilizing caveolae structure by temperature reduction or destabilizing caveolae by cholesterol depletion resulted in changes consistent with the hypothesis that proper caveolae structure plays an important role in inhibition of signaling molecules and that deformation mediates mechanotransduction, resulting in changes in activation of ERK2.
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Fabrication and Wavelength Separation Analysis of 3¡Ñ3 Fused Tapered Optical Fiber CouplerChen, Yueh-shen 30 August 2012 (has links)
Use the adjustable diameter fiber splicing platform to manufactured coupler, N fibers were put into the appropriate aperture silica capillaries, and then changed the taper model to manufactured fiber coupler [1], and adjusted the taper model and fusion parameters to reduce the fiber transmission loss and reduce the diameter of the fibers to achieve the optical coupling effect.
We preferred to the Eisenmann & Weidel in 1988 [2]. It is a low loss of the fusion type equilateral triangle of 3¡Ñ3 fiber coupler. And we will study the asymmetric shape of an 3¡Ñ3 fiber coupler, the research method is the use of arc heating. The fiber has smaller heating area and the heating position which can be controlled. With the parameters which BeamPorp, we cut the fiber coupler and to discuss its cross-section. By the different geometric distribution of fibers, and the core spacing, we discuss the spectra of the OSA to change the coupling site.
We changed the interior structure to make the power coupling to a marked effect; if we could control the asymmetric coupler explicitly then we could achieve
the transmission power [3], power coupling, and the multiple spectra of light.
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Modeling planar 3-valence meshesGonen, Ozgur 15 May 2009 (has links)
In architectural and sculptural practice, the eventual goal is constructing the
shapes that have been designed. Due to fabrication considerations, shapes with planar
faces are in demand for these practices.
In this thesis, a novel computational modeling approach to design constructible
shapes is introduced. This method guarantees that the resulting shapes are planar
meshes with 3-valence vertices, which can always be physically constructed using
planar or developable materials such as glass, sheet metal or plywood. The method
introduced is inspired by the traditional sculpture and is based on the idea of carving
a mesh by using slicing planes. The process of determining the slicing planes can
either be interactive or automated.
A framework is developed which allows user to sculpt shapes by using the in-
teractive and automated processes. The framework allows user to cut a source mesh
based on its edges, faces or vertices. The user can sculpt various kinds of developable
surfaces by cutting the parallel edges of the mesh. The user can also introduce in-
teresting conical patterns by cutting dierent vertex, edge, face combinations of the
mesh.
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A dicer-like protein is essential for normal sexual development and meiotic silencing in the filamnentous fungus neurospora crassaMcLaughlin, Malcolm Thomas 15 May 2009 (has links)
The presence of an unpaired copy of a gene during meiosis triggers the
silencing of every copy of that gene in the diploid ascus cell of Neurospora
crassa, a phenomenon called Meiotic Silencing. This phenomenon has two
stages: trans-sensing and meiotic silencing. If a DNA region is not detected on
the opposite homologous chromosome early in meiosis (a trans-sensing failure),
a signal corresponding to the unpaired region is produced that transiently
silences expression of all homologous sequences. Meiotic silencing is related to
RNA Silencing, a phenomenon that employs RNA-dependent RNA Polymerases
(RdRPs), Argonautes, and Dicers. Dicers cleave double-stranded RNA (dsRNA)
into 21-23 nucleotide RNAs. In the filamentous fungus Neurospora crassa, two
RNA silencing pathways have been identified; one is active during mitosis, and
the other is active during meiosis. The mitotic RNA silencing pathway, known as
“quelling”, involves an RdRP (quelling-deficient-1--qde-1), an Argonaute-like
protein (quelling-deficient-2--qde-2), and two Dicer-like proteins (dicer-like-1--dcl-1 and dicer-like-2--dcl-2). Previous studies in N. crassa also revealed the
involvement of an RdRP (Suppressor of ascus dominance-1--Sad-1) and an
Argonaute-like protein (Suppressor of meiotic silencing-2--Sms-2) in meiotic
silencing, suggesting that meiotic silencing is RNA-dependent and raising the
question of whether a Dicer is involved in meiotic silencing.
In this work, we tested the participation in meiotic silencing of the dcl-1 gene of
N. crassa, which codes for a Dicer-like protein we call Suppressor of meiotic
silencing-3--Sms-3. Crosses homozygous for mutant alleles of Sms-3 are
barren, indicating that the gene is also essential for sexual development. Due to
this homozygous sterility, we could only test the involvement of Sms-3 in meiotic
silencing in heterozygous crosses. Under these conditions, we observed
suppression of the meiotic silencing which would have otherwise been induced
by the presence of unpaired DNA of reporter genes. We conclude that the Dicerlike
protein Sms-3 is required for both meiotic RNA silencing and sexual
development.
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Synthesis of 5-Substituted Isoxazolidines by [3 plus 2] Cycloaddition of Nitrones Generated in an Unusual Way from Nitrosobenzene and StyreneKang, Jun Yong 20 January 2010 (has links)
A new synthetic method toward 5-substituted isoxazolidines by [3 plus 2]
cycloaddition of nitrones generated from nitrosobenzene and styrene was discovered.
The formation of nitrones from nitrosobenzene and mono-substituted aromatic
styrenes was demonstrated. The cycloaddition reactions between styrenes and
nitrosobenzenes work well when a moderate excess of styrenes was employed. The
labeling studies support that cleavage of the styrene double bond occurred and accounted
for all the carbons in the starting materials and products.
A [3 plus 2] dipolar cycloaddition is implicated by the available mechanistic data and
allows for the rapid assembly of various substituted isoxazolidines directly from
nitrosobenzenes, electron deficient alkenes, and styrene.
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Effect of Omega 3 Polyunsaturated Fatty Acids (PUFAs) on Markers of Inflammation in Young Horses in TrainingLucia, Jessica Lauren 2009 December 1900 (has links)
Sixteen horses (2 to 4 yr; 357 to 439 kg BW) were utilized in a randomized complete block design for a 140 d trial to determine effect of omega 3 PUFAs (n-3) supplementation on markers of inflammation in young horses in training. Horses were fed treatments consisting of a control diet (n = 8) fed at 1% BW (as fed) or a treatment diet (n = 8) of concentrate fed at 0.75% BW (as fed) and 350 g of a marine n-3 supplement formulated to provide 15 g of eicosapentaenoic acid (EPA) and 20 g of docosahexaenoic acid (DHA). Body weight and body condition scores (BCS) were obtained biweekly and concentrate adjusted accordingly.
Horses were exercised 5 d/wk by students in an equine training course. Type of activity and duration was monitored, along with heart rate to quantify workload. Exercise protocol was divided into 2 phases: phase I (d 0 to110) consisted of ground work and early training under saddle, and phase II (d 111 to 140) consisted of advance maneuvers and moderate workload.
Synovial fluid was obtained from right radial carpal joint by arthrocentesis every 28 d and was analyzed for white blood cell count (WBC), total protein (TP), and specific gravity (SG). Serum concentrations of carboxypeptide type II collagen (CPII) and chondroitin sulfate 846 (CS-846) were analyzed by ELISA kits. Dietary treatment did not affect synovial WBC, TP, or SG. Also, concentrations of WBC and TP also did not differ over time. SG increased over time (P < 0.001) as horses moved from phase I to phase II of the trial. Dietary treatment did not influence concentrations of CPII or CS-846. CS-846 tended to increase over time (P = 0.09) and CPII concentrations also increased (P < 0.001) in response to changes in exercise. Furthermore, all horses gained BW and BCS throughout the trial (P < 0.001), but values were not influenced by treatment. This data indicates further studies are needed to determine the efficacy of n-3 supplementation as a preventative measure against development of osteoarthritis.
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Effects of Exogenously Applied Indole-3-Acetic Acid (IAA) to CottonClement, Jenny D. 2010 May 1900 (has links)
There is a need in the cotton industry for cultivars with enhanced lint yield potential and high-quality fiber properties. Indole-3-acetic acid (IAA) is a phytohormone that is predominantly responsible for cell elongation and required for primary elongation in cotton fiber development. An increase in IAA at specific fiber developmental stages may promote increased lint percent and longer fibers. Objectives of this research project were to determine how exogenous applications in a field environment affect fiber traits and lint yield potential in diverse genotypes. The first study examined application methods to ascertain the optimal placement and timing of IAA. The second study focused on genotype reactions to elevated levels of IAA. Results indicate exogenously applied IAA provided a potential yield increase but did not improve fiber length. Further research needs to be conducted to effectively understand IAA’s role in fiber development and establishing protocols for maximizing IAA potential in a field environment.
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Synthetic Studies Toward Kainic acid and LycoraneLiu, Yen-ting 04 July 2007 (has links)
We have developed an one-pot reaction procedure to polysubstituted pyroglutamates with three contiguous chiral centers. The results were applied to the synthetic studies toward kainic acid and lycorane.
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ASEAN AT THE THIRD TRANSITION: GROPING FOR A NEW REGIONALISM IN EAST ASIASUDO, Sueo, 須藤, 季夫 03 1900 (has links)
No description available.
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