Publications by authors named "Kho T"

Premise: The consequences of acidity for plant performance are profound, yet the prevalence and causes of low pH in bromeliad tank water are unknown despite its functional relevance to key members of many neotropical plant communities.

Methods: We investigated tank water pH for eight bromeliad species in the field and for the widely occurring Guzmania monostachia in varying light. We compared pH changes over time between plant and artificial tanks containing a solution combined from several plants.

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Thin SiO interlayers are often formed naturally during the deposition of transition metal oxides on silicon surfaces due to interfacial reaction. The SiO layer, often only several atomic layers thick, becomes the interface between the Si and deposited metal oxide and can therefore influence the electrical properties and thermal stability of the deposited stack. This work explores the potential benefits of controlling the properties of the SiO interlayer by the introduction of pregrown high-quality SiO which also inhibits the formation of low-quality SiO from the metal-oxide deposition process.

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Premise: Because of its broad range in the neotropical rainforest and within tree canopies, the tank bromeliad Guzmania monostachia was investigated as a model of how varying leaf hydraulic conductance (K ) could help plants resist and recover from episodic drought. The two pathways of K , inside and outside the xylem, were also examined to determine the sites and causes of major hydraulic resistances within the leaf.

Methods: We measured leaf hydraulic conductance for plants in the field and laboratory under wet, dry, and rewetted conditions and applied physiological, anatomical, and gene expression analysis with modeling to investigate changes in K .

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Background/objectives: We investigated the prevalence and correlates of discrepancies between self-reported sleep quality (Pittsburgh Sleep Quality Index) and objective sleep efficiency (actigraphy) in older adults with mild cognitive impairment (MCI) and subsyndromal depression.

Methods: This was a secondary analysis of a clincial trial with 59 adults aged 60 years and older with MCI and subsyndromal depression. We included baseline data on participants' subjective sleep quality, objective sleep efficiency, depressive symptoms, insomnia diagnosis, and cognitive functioning.

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Background: Phototherapy has been a mainstay in the treatment of mycosis fungoides (MF). However, the recent findings of UV-induced p53 mutations in advanced MF suggest that phototherapy may contribute to disease progression.

Objective: The objective of this study was to evaluate the effect of phototherapy on the time to tumor progression and overall survival in MF.

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The reduction of parasitic recombination processes commonly occurring within the silicon crystal and at its surfaces is of primary importance in crystalline silicon devices, particularly in photovoltaics. Here we explore a simple, room temperature treatment, involving a nonaqueous solution of the superacid bis(trifluoromethane)sulfonimide, to temporarily deactivate recombination centers at the surface. We show that this treatment leads to a significant enhancement in optoelectronic properties of the silicon wafer, attaining a level of surface passivation in line with state-of-the-art dielectric passivation films.

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This paper introduces new development technique to improve the Scanning Electron Microscope (SEM) image quality and we name it as sub-blocking multiple peak histogram equalization (SUB-B-MPHE) with convolution operator. By using this new proposed technique, it shows that the new modified MPHE performs better than original MPHE. In addition, the sub-blocking method consists of convolution operator which can help to remove the blocking effect for SEM images after applying this new developed technique.

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Lipid-laden macrophages contribute to pathologies as diverse as atherosclerosis and tuberculosis. Three common stimuli are known to promote macrophage lipid storage: low tissue oxygen tension (pO2), low extracellular pH (pHo), and exposure to agonists such as bacterial LPS. Noting that cells responding to low pO2 or agonistic bacterial molecules often decrease pHo by secreting lactic and other carboxylic acids, we studied how pHo influences the stimulation of triacylglycerol (TAG) storage by low pO2 and LPS.

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Macrophages in infected tissues may sense microbial molecules that significantly alter their metabolism. In a seeming paradox, these critical host defense cells often respond by increasing glucose catabolism while simultaneously storing fatty acids (FA) as triglycerides (TAG) in lipid droplets. We used a load-chase strategy to study the mechanisms that promote long term retention of TAG in murine and human macrophages.

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Using a large consortium of undergraduate students in an organized program at the University of California, Los Angeles (UCLA), we have undertaken a functional genomic screen in the Drosophila eye. In addition to the educational value of discovery-based learning, this article presents the first comprehensive genomewide analysis of essential genes involved in eye development. The data reveal the surprising result that the X chromosome has almost twice the frequency of essential genes involved in eye development as that found on the autosomes.

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How can you combine professional-quality research with discovery-based undergraduate education? The UCLA Undergraduate Consortium for Functional Genomics provides the answer

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The identification of recurrent or residual tumor tissue is sometimes complicated. The authors describe a 53-year-old woman in whom I-123 metaiodobenzylguanidine (MIBG) scintigraphy revealed a pheochromocytoma in the right adrenal gland. After the tumor was removed, the patient's catecholamine levels normalized.

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Fabry's disease is an X-linked hereditary disorder resulting in accumulation of a glycolipid (galactosylgalactosyl glucosylceramide) due to deficiency of alpha-galactosidase A. The diagnosis can be made by histopathologic examination of skin biopsy, low activity of alpha-galactosidase in leucocytes and genetic examination. Treatment is symptomatic.

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Streptozotocin (STZ), a diabetogenic agent, is thought to damage pancreatic beta-cells by activating immune mechanisms and by alkylating DNA. In the present study, we demonstrated that STZ can produce nitric oxide (NO), a bioregulatory and cytotoxic molecule. When STZ was dissolved in a sodium phosphate buffer (50 mM, pH 7.

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