Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 20 of 20

Full-Text Articles in Physical Sciences and Mathematics

Statistical Measurements Of Dispersion Measure Fluctuations Of Frbs, Siyao Xu, David H. Weinberg, Bing Zhang Nov 2021

Statistical Measurements Of Dispersion Measure Fluctuations Of Frbs, Siyao Xu, David H. Weinberg, Bing Zhang

Physics & Astronomy Faculty Research

Extragalactic fast radio bursts (FRBs) have large dispersion measures (DMs) and are unique probes of intergalactic electron density fluctuations. By using the recently released First CHIME/FRB Catalog, we reexamined the structure function (SF) of DM fluctuations. It shows a large DM fluctuation similar to that previously reported in Xu & Zhang, but no clear correlation hinting toward large-scale turbulence is reproduced with this larger sample. To suppress the distortion effect from FRB distances and their host DMs, we focus on a subset of CHIME catalog with DM < 500 pc cm-3. A trend of nonconstant SF and nonzero correlation function (CF) at angular separations θ less than 10 is seen, but with large statistical uncertainties. The difference found between SF and that derived from CF at θ ≲ 10 can be ascribed to the large statistical uncertainties or the density inhomogeneities on scales on the order of 100 Mpc. The possible correlation of electron density fluctuations and inhomogeneities of density distribution should be tested when several thousands of FRBs are available.


Impact Of Neoantigen Expression And T-Cell Activation On Breast Cancer Survival, Wenjing Li, Amei Amei, Francis Bui, Saba Norouzifar, Lingeng Lu, Zuoheng Wang Jun 2021

Impact Of Neoantigen Expression And T-Cell Activation On Breast Cancer Survival, Wenjing Li, Amei Amei, Francis Bui, Saba Norouzifar, Lingeng Lu, Zuoheng Wang

Mathematical Sciences Faculty Research

Neoantigens are derived from tumor-specific somatic mutations. Neoantigen-based syn-thesized peptides have been under clinical investigation to boost cancer immunotherapy efficacy. The promising results prompt us to further elucidate the effect of neoantigen expression on patient survival in breast cancer. We applied Kaplan–Meier survival and multivariable Cox regression models to evaluate the effect of neoantigen expression and its interaction with T-cell activation on overall survival in a cohort of 729 breast cancer patients. Pearson’s chi-squared tests were used to assess the relationships between neoantigen expression and clinical pathological variables. Spearman correlation analysis was conducted to identify correlations between neoantigen expression, mutation …


Tricyclic Antidepressant Use And Risk Of Fractures: A Meta-Analysis Of Cohort Studies Through The Use Of Both Frequentist And Bayesian Approaches, Qing Wu, Yingke Xu, Yueyang Bao, Jovan Alvarez, Mikee Lianne Gonzales Aug 2020

Tricyclic Antidepressant Use And Risk Of Fractures: A Meta-Analysis Of Cohort Studies Through The Use Of Both Frequentist And Bayesian Approaches, Qing Wu, Yingke Xu, Yueyang Bao, Jovan Alvarez, Mikee Lianne Gonzales

School of Medicine Faculty Publications

Background: Research findings regarding the association between tricyclic antidepressant (TCA) treatment and the risk of fracture are not consistent; we aimed to assess whether people who take TCAs are at an increased fracture risk. Methods: Relevant studies published through June 2020 were identified through database searches of MEDLINE, EMBASE, Scopus, PsycINFO, ISI Web of Science, WorldCat Dissertations and Theses from each database’s inception, as well as through manual searches of relevant reference lists. Two researchers independently performed literature searches, study selection, data abstraction and study appraisal by using a standardized protocol. Frequentist and Bayesian hierarchical random-effects models were used for …


Interplay Of Trna-Derived Fragments And T Cell Activation In Breast Cancer Patient Survival, Nayang Shan, Ningshan Li, Qile Dai, Lin Hou, Xiting Yan, Amei Amei, Lingeng Lu, Zuoheng Wang Aug 2020

Interplay Of Trna-Derived Fragments And T Cell Activation In Breast Cancer Patient Survival, Nayang Shan, Ningshan Li, Qile Dai, Lin Hou, Xiting Yan, Amei Amei, Lingeng Lu, Zuoheng Wang

Mathematical Sciences Faculty Research

Effector CD8+ T cell activation and its cytotoxic function are positively correlated with improved survival in breast cancer. tRNA-derived fragments (tRFs) have recently been found to be involved in gene regulation in cancer progression. However, it is unclear how interactions between expression of tRFs and T cell activation affect breast cancer patient survival. We used Kaplan–Meier survival and multivariate Cox regression models to evaluate the effect of interactions between expression of tRFs and T cell activation on survival in 1081 breast cancer patients. Spearman correlation analysis and weighted gene co-expression network analysis were conducted to identify genes and pathways that …


Utility Of Inflammatory Markers To Predict Adverse Outcome In Acute Pancreatitis: A Retrospective Study In A Single Academic Center, Mohamad Mubder, Banreet Dhindsa, Danny Nguyen, Syed Saghir, Chad Cross, Ranjit Makar, Gordon Ohning Jul 2020

Utility Of Inflammatory Markers To Predict Adverse Outcome In Acute Pancreatitis: A Retrospective Study In A Single Academic Center, Mohamad Mubder, Banreet Dhindsa, Danny Nguyen, Syed Saghir, Chad Cross, Ranjit Makar, Gordon Ohning

School of Medicine Faculty Publications

Background/Aim: Acute pancreatitis (AP) is a commonly encountered emergency where early identification of complicated cases is important. Inflammatory markers like lymphocyte to monocyte ratio (LMR) and neutrophil to lymphocyte ratio (NLR) are simple and readily available markers. In this study, we evaluated the utility of these markers in the early identification of patients with complicated AP. Patients and Methods: All patients with a diagnosis of AP admitted to the University Medical Center in Las Vegas/Nevada between August 2015 and September 2018 were identified using ICD-10 codes. Medical records were reviewed retrospectively. Epidemiological measures and their associated confidence intervals were calculated …


Hdr Brachytherapy For Skin Cancer Using H.A.M. Applicator, Timothy Richard Thatcher May 2020

Hdr Brachytherapy For Skin Cancer Using H.A.M. Applicator, Timothy Richard Thatcher

UNLV Theses, Dissertations, Professional Papers, and Capstones

Skin cancer is the most common type of malignancy affecting both men and women in the United States. A majority of these cases are nonmelanoma skin cancers (NMSC) such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). The goal of any skin cancer treatment is to cure the lesion itself while also preserving function and optimizing superficial cosmesis. High dose rate (HDR) brachytherapy provides an alternative to superficial x-ray or electron beam for skin cancer treatment. Utilizing an Iridium 192 source soldered to the end of a wire, surface dose can be administered at predetermined positions with sharper …


A Study On Automated Process For Extracting White Blood Cellular Data From Microscopic Digital Injured Skeletal Muscle Images, Bibek Karki May 2016

A Study On Automated Process For Extracting White Blood Cellular Data From Microscopic Digital Injured Skeletal Muscle Images, Bibek Karki

UNLV Theses, Dissertations, Professional Papers, and Capstones

Skeletal muscle injury is one of the common injuries caused by high-intensity sports activities, military related works, and natural disasters. In order to discover better therapies, it is important to study muscle regeneration process. Muscle regeneration process tracking is the act of monitoring injured tissue section over time, noting white blood cell behavior and cell-fiber relations. A large number of microscopic images are taken for tracking muscle regeneration process over multiple time instances. Currently, manual approach is widely used to analyze a microscopic image of muscle cross section, which is time consuming, tedious and buggy.

Automation of this research methodology …


Creating A Dynamic, Multi-Purpose Correction For Multiple Geometries And Field Sizes To Account For Off-Axis And Asymmetric Backscatter With Varian Portal Dosimetry, Remy Manigold May 2016

Creating A Dynamic, Multi-Purpose Correction For Multiple Geometries And Field Sizes To Account For Off-Axis And Asymmetric Backscatter With Varian Portal Dosimetry, Remy Manigold

UNLV Theses, Dissertations, Professional Papers, and Capstones

Intensity modulated radiation therapy and volumetric modulated arc therapy are increasingly common in radiation therapy due to their benefits of target conformity and normal tissue sparing. Due to the complexities of plan delivery and the precision required, the dose delivered must be accurately measured for quality assurance (QA). One of the most efficient ways to perform patient-specific QA when using clinical linear accelerators (linac) is to use an electronic portal imaging device (EPID). Amorphous silicon (aSi) Electronic Portal Imaging Devices (EPIDs) are attached to the linac and can provide real-time feedback with spatial resolution on the order of sub-millimeter pixel …


Synthesis And Characterization Of Novel Platinum(Ii) And Platinum(Iv) Complexes Containing 4,4′--Disubstituted--2,2′--Bipyridine Ligands For The Treatment Of Cancer, Van Vo Aug 2014

Synthesis And Characterization Of Novel Platinum(Ii) And Platinum(Iv) Complexes Containing 4,4′--Disubstituted--2,2′--Bipyridine Ligands For The Treatment Of Cancer, Van Vo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Three series of platinum(II) and platinum(IV) complexes containing 4,4′-disubstituted-2,2′-bipyridine ligands have been synthesized and characterized by 1H NMR, 13C NMR spectroscopy, elemental analysis, mass spectroscopy, and differential scanning calorimetry measurements. The MTS cell proliferation assay was used to examine the in vitro anti-proliferative activities of these complexes in various human breast, lung, and prostate cancer cells. The cell's response to the complexes varies between different cell lines; however, the low EC50 values determined from the MTS data indicate that several of the complexes are much more potent than cisplatin.

Flow cytometric analysis of selected compounds revealed induction of apoptosis …


Gate Monte Carlo Simulations In A Cloud Computing Environment, Blake Austin Rowedder Aug 2014

Gate Monte Carlo Simulations In A Cloud Computing Environment, Blake Austin Rowedder

UNLV Theses, Dissertations, Professional Papers, and Capstones

The GEANT4-based GATE is a unique and powerful Monte Carlo (MC) platform, which provides a single code library allowing the simulation of specific medical physics applications, e.g. PET, SPECT, CT, radiotherapy, and hadron therapy. However, this rigorous yet flexible platform is used only sparingly in the clinic due to its lengthy calculation time. By accessing the powerful computational resources of a cloud computing environment, GATE's runtime can be significantly reduced to clinically feasible levels without the sizable investment of a local high performance cluster. This study investigated a reliable and efficient execution of GATE MC simulations using a commercial cloud …


Factors Associated With Parental Decision Making And Childhood Vaccination, Zuwen Qiu-Shultz Dec 2013

Factors Associated With Parental Decision Making And Childhood Vaccination, Zuwen Qiu-Shultz

UNLV Theses, Dissertations, Professional Papers, and Capstones

In order to better understand factors affecting immunization status, logistic regression was used to assess the association of various socio-demographic factors and whether parents would have their child immunized if not a state mandate. Factors included in the study were race, household income, number of children in the household, number of adults in the household, if the child had a primary provider, if the child had a health check-up in the last twelve months, and medical insurance status of the child. The combined Nevada Kindergarten Health Survey Result of 2009-2010 (Year Two) and 2010-2011 (Year Three) conducted by the Nevada …


Alpcs(2a)-Mediated Photochemical Internalization Of Bleomycin And Concurrent Hyperthermia Of Multicellular Tumor Spheroids, Aaron Andersen May 2013

Alpcs(2a)-Mediated Photochemical Internalization Of Bleomycin And Concurrent Hyperthermia Of Multicellular Tumor Spheroids, Aaron Andersen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Treatments for glioblastoma multiforme and invasive ductal carcinoma involve surgical resection and adjuvant or concurrent targeted therapies. The goal of the secondary treatment is to reduce the cancer cells in the resection margin and other areas of suspected involvement. Photochemical internalization is a targeted therapy using light to activate photosensitizers embedded in cellular structures to improve the delivery of macromolecules within the cell.

In a previous study, optimized treatment parameters including radiant exposure, and irradiance, concentration of AlPcS(2a), temperature, and the concentration of bleomycin were determined for human ACBT glioma multicell spheroids. The current study investigates the effectiveness of the …


Effects Of Hyperthermia On Photochemical Internalization-Mediated Delivery Of Bleomycin, Christina Schlazer May 2012

Effects Of Hyperthermia On Photochemical Internalization-Mediated Delivery Of Bleomycin, Christina Schlazer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Standard treatment protocols for high-grade gliomas, such as glioblastoma multiforme (GBM), are highly ineffective due to their inability to eradicate infiltrating tumor cells. Improvements in overall survival are likely to be realized only with the development of more effective localized therapies capable of eradicating tumor cells in the surgical resection margin and beyond. Photochemical internalization (PCI) is a localized light-based therapeutic modality that enhances the efficacy of therapeutic macromolecules including chemotherapeutic agents such as bleomycin. A number of studies have shown that this photodynamic therapy (PDT) - based modality may prove effective in the treatment of high-grade gliomas.

Three-dimensional multicell …


Breast Cancer Screening Practices Among American Indians And Alaska Natives In The Midwest, Christine M. Daley, Melissa Filippi, Aimee S. James, Sarah Brokenleg, Stacy Braiuca, K. A. Greiner, Won S. Choi Mar 2012

Breast Cancer Screening Practices Among American Indians And Alaska Natives In The Midwest, Christine M. Daley, Melissa Filippi, Aimee S. James, Sarah Brokenleg, Stacy Braiuca, K. A. Greiner, Won S. Choi

Journal of Health Disparities Research and Practice

American Indian and Alaska Native (AI/AN) women currently have some of the highest mortality rates from breast cancer for any racial/ethnic group in the United States and some of the lowest screening rates. However, current data are not available for regional differences in screening, which can result in dramatically different stage at diagnosis and mortality. We conducted surveys with 120 focus group participants in a needs assessment of mammography among AI/AN in the greater Kansas City metropolitan area and parts of Northeast Kansas. We found that among women under age 40, for whom recommended screenings include only annual clinical breast …


Cell Migration Dynamics After Alteration Of Cell-Cell Contacts In Fibrosarcoma And Glioblastoma Cell Lines, Hassan S. Rizvi, Ronald K. Gary Aug 2011

Cell Migration Dynamics After Alteration Of Cell-Cell Contacts In Fibrosarcoma And Glioblastoma Cell Lines, Hassan S. Rizvi, Ronald K. Gary

Undergraduate Research Opportunities Program (UROP)

Cell migration is a vital component of metastasis. In this study, our intent was to study cell migration by alteration of the Wnt/GSK-3 Pathway. Since BeSO4 is a known GSK-3 kinase inhibitor, we hypothesized that this agent would cause cell migration to decrease as a result of β-catenin stabilization. Two human cell lines, HT-1080 (fibrosarcoma) and A172 (glioblastoma), were used to observe migration levels in the presence and absence of BeSO4. Our results show that cell migration is diminished for cells that were pre-treated with BeSO4, in comparison to the untreated (control) cells.


A Comparison Of Spatio-Temporal Prediction Methods Of Cancer Incidence In The U.S, Michelle Hamlyn Aug 2011

A Comparison Of Spatio-Temporal Prediction Methods Of Cancer Incidence In The U.S, Michelle Hamlyn

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cancer is the cause of one out of four deaths in the United States, and in 2009, researchers expected over 1.5 million new patients to be diagnosed with some form of cancer. People diagnosed with cancer, whether a common or rare type, need to undergo treatments, the amount and kind of which will depend on the severity of the cancer. So how do healthcare providers know how much funding is needed for treatment? What would better enable a pharmaceutical company to determine how much to allocate for research and development of drugs, the amount of each drug to manufacture, or …


Modeling Mortality Rates For Leukemia Between Men And Women In The United States, Blessed Quansah May 2011

Modeling Mortality Rates For Leukemia Between Men And Women In The United States, Blessed Quansah

UNLV Theses, Dissertations, Professional Papers, and Capstones

Leukemia related deaths increased dramatically over the last forty years. Leukemia is a malignant disease or cancer of the bone marrow and blood. It is characterized by the uncontrolled accumulation of blood cells. Leukemia is divided into two categories: myelogenous or lymphocytic, each of which can be acute or chronic. The terms, myelogenous or lymphocytic denote the cell type involved.

In this thesis, the proposed modeling techniques are applied to leukemia deaths data from the Surveillance Epidemiology and End Results (SEER). In particular, annual deaths data from 1969 to 2007 are used in the data analysis, which includes three major …


The Determinants Of Colorectal Cancer Survival Disparities In Nevada, Lucas N. Wassira Dec 2010

The Determinants Of Colorectal Cancer Survival Disparities In Nevada, Lucas N. Wassira

UNLV Theses, Dissertations, Professional Papers, and Capstones

Different population groups across Nevada and throughout the United States suffer disproportionately from colorectal cancer and its after-effects. Overcoming cancer health disparities is important for lessening the burden of cancer. There has been an overall decline in the incidence of and mortality from colorectal cancer (CRC). This is likely due, in part, to the increasing use of screening procedures such as Fecal Occult Blood Test (FOBT) and/or endoscopy, which can reduce the risk of CRC mortality by fifty percent. Nevertheless, screening procedures are routinely used by only fifty percent of Americans aged fifty years and older. Despite overall mortality decreasing …


Y-Aminobutyric Acid Inhibits Synergistic Interleukin-6 Release And Increases Intracellular Cytokine Content In C6 Astrocytoma Cells In Vitro, Daniella Sandoval, Becky M. Hess, Bryan L. Spangelo Aug 2010

Y-Aminobutyric Acid Inhibits Synergistic Interleukin-6 Release And Increases Intracellular Cytokine Content In C6 Astrocytoma Cells In Vitro, Daniella Sandoval, Becky M. Hess, Bryan L. Spangelo

Undergraduate Research Opportunities Program (UROP)

Alzheimer’s disease (AD) is a neurodegenerative disorder that is characterized by memory loss and is the most common cause of dementia. It is has been hypothesized that pro-inflammatory cytokines induce the inflammation that is believed to be the cause of the neuronal death that is associated with AD. γ-aminobutyric acid (GABA) is a major inhibitory neurotransmitter in the Central Nervous System possessing membrane hyperpolarization or depolarization activities. A decline in GABA may enhance cytokine release in Alzheimer’s disease resulting in neuroinflammation. Therefore, we investigated the GABA-mediated suppression of the synergistic release of interleukin-6 (IL-6) induced by interleukin 1- (IL-1) and …


Synthesis Of Novel Aromatic Quinols For Colon And Renal Cancers, Bradley J. Davey, Tae Soo Jo, Pradip K. Bhowmik Aug 2010

Synthesis Of Novel Aromatic Quinols For Colon And Renal Cancers, Bradley J. Davey, Tae Soo Jo, Pradip K. Bhowmik

Undergraduate Research Opportunities Program (UROP)

Colon Cancer: The third most common cancer in USA. More than 1 million Americans currently living with colon cancer. 148,810 new cases expected in 2010. 50,000 deaths annually.

Renal Cancer: Approximately 58,000 people diagnosed in USA annually. Seventh most common cancer and tenth most common cause of cancer related death in men.

Aromatic quinols have demonstrated in vitro antitumor activity. Three heteroaromatic quinols show antitumor activity.