Effect of dry particle coating on the properties of cohesive pharmaceutical powders

Engineered particles, which have undergone surface modification via dry coating, have been previously shown to have improved flow and handling properties. The improvements in these properties can be applied and are very useful for a number of industrial applications, in this case the pharmaceutical industry. This work investigates the effect of dry particle coating to improve the flowability of cohesive active pharmaceutical ingredient (API) powders and their blends. Improving the flow properties of cohesive API powders can significantly improve their handling and subsequent use for pharmaceutical processes such as formulation and manufacturing processing operations. Although it has been shown that these surface modified powders flow better as indicated by reduced angle of repose and faster or more uniform flow out of a funnel, more quantitative methods of characterization are needed to fully understand the mechanism of coating and extent of improvement. Acetaminophen, ibuprofen and other powders were the APIs considered in this work. They were surface modified via dry coating of nano-additives using several different devices. The study considered the use of both hydrophobic and hydrophilic nano-additives. Since the dry coating process is not easily achieved by simple mixing of the API and nano additives, high and/or sustained levels of shear are required to disperse the silica over the API particle. There is a need to develop a new dry coating process that is reproducible, scalable and continuous so that dry coating can be applied to (1) simplify formulations, (2) enable higher API levels, and (3) improve overall powder and drug product manufacturing performance. In contrast to previous studies that only employed angle of repose to evaluate flow improvement, in this work various quantitative flow characterization techniques are used to assess the changes in flow properties. In addition to use of MAIC and hybridizer which are batch devices, this work also includes development of continuous dry coating methodology which is based on a typical pharmaceutical powder processing device, namely comil. The comil is found to be fast and efficient, as it is a continuous process with little loss of material. The comil has also been scaled up to pilot scale, indicating that it could easily be implemented in existing formulation and manufacturing processes. The powders that have undergone surface modification via dry coating techniques are first analyzed for the extent of coating using scanning electron microscopy (SEM) and then the powders are analyzed for their particle size distribution using the Sympatec Helos/Rodos system under varying dispersion conditions to ensure there was no attrition during the coating process. Additionally, a variety of techniques are employed to characterize the powder flow and bulk handling properties, which are important for large scale pharmaceutical manufacturing. Extensive characterization of the powder\u27s flow properties were performed using both novel methods, such as vibrated packed density, as well as industry standard techniques such as shear testing via the Schulze tester, the Freeman FT4 Rheometer and the Hosokawa Powder Tester. Other powder properties such as bulk and tapped densities are also evaluated. The results of these tests are compared with those for untreated API powders in order to examine the enhancement of the powder properties due to the surface modification. This work also clearly illustrates that the pharmaceutical materials undergo significant attrition if the dry coating devices are not optimized. This work intends to position dry coating as a platform technology and show that dry coating based surface modification has the potential to become a routine tool for use in pharmaceutical industry to enable better formulations and aid in manufacturing

Studies On The Antiretroviral Mechanism Of Action Of Clofarabine

University of Minnesota Ph.D. dissertation. July 2014. Major: Molecular, Cellular, Developmental Biology and Genetics. Advisor: Louis Mansky. 1 computer file (PDF); xi, 143 pages.Since the beginning of the AIDS epidemic over thirty years ago, human immunodeficiency virus type 1 (HIV-1) has infected seventy-five million people and has claimed the lives of over thirty-six million people worldwide, making HIV/AIDS one of the most devastating global infectious disease epidemics in history. To date, no preventative vaccine or curative treatment exists for HIV-1 infection. The availability of drugs to treat HIV-1 infection has led to drug resistance, which limits the utility of antiviral therapy. This has provided the basis for the continual need for identifying new targets for antiviral drugs. This dissertation investigated the antiretroviral activity and mechanism of action for clofarabine, a purine nucleoside antimetabolite. Clofarabine was demonstrated to exert antiretroviral activity against both HIV-1 and human immunodeficiency virus type 2 (HIV-2). Studies directed at elucidating the antiretroviral mechanism of action support a model in which clofarabine acts as an inhibitor of ribonucleotide reductase, leading to imbalances in cellular dNTP pools, which reduces viral infectivity through an increase in the HIV-1 mutation rate

A DYNAMIC GENERAL EQUILIBRIUM ANALYSIS OF U.S. BIOFUELS PRODUCTION

With the rising global interest in energy security and climate change mitigation, biofuels have gained the prominent attention of researchers and policy makers. The U.S. has emerged as the leading producer of biofuels and is aiming for achieving a target of 36 billion gallons of renewable fuels by 2022 under its updated renewable fuels standard (RFS2) policy. In this paper, we study the longer-term global implications of large-scale renewable fuels production in the U.S. We utilize the GTAP v7.1 data base and introduce a detailed breakdown of agricultural crops, first and second generation biofuels and by-products. We update this fully disaggregated data base to reflect the 2010 global economy, based on secondary data for the sectors and regions included. We adapt the Applied Dynamic Analysis of Global Economy (ADAGE) model developed by Ross (2009) into a recursive dynamic framework and introduce agriculture, biofuels, and land use linkages. We construct a dynamic baseline from 2010 through 2050 in five-year time steps. The dynamics in the model comes from growth in GDP, population, capital accumulation, labor productivity, growth in natural resource stocks, and technological changes in the energy intensive and agricultural sectors. We implement a representative RFS2 policy scenario in the U.S for 2025, using two alternative approaches: (i) RFS permits approach – which assumes biofuels and petroleum fuels are perfect substitutes after adjusting for energy content, and (ii) Target share of biofuels in transportation fuels approach – which treats biofuels and petroleum fuels as imperfect substitutes. Both approaches offer insights regarding potential policy impacts, particularly on the international market and indirect land use change. Because the share approach keeps the biofuels share fixed in the regions outside the U.S., it does not result in dramatic changes in the rest of the world. In the permits approach, however, the regions without a specific policy requiring a given level of biofuels tend to reduce biofuels consumption. This is a result of the reduction in relative price of petroleum products as U.S. policy increases demand for biofuels and reduces global demand for petroleum, making renewable fuels less cost-competitive in the rest of the world.ADAGE, Biofuels, Computable General Equilibrium, Recursive Dynamic, Resource /Energy Economics and Policy,

A Qualitative Inquiry of a Three-Month Virtual Practicum Program on Youth with Visual Impairments and Their Coaches

Research has shown that the practicum experience for professional preparation students in physical education teacher education programs related to teaching youth with disabilities can improve self-efficacy. It is not currently known if a virtual program can be effective for the professional preparation students or the participants. The objective of this study was to determine the experiences of the participants of a three-month virtual practicum program. In this phenomenological study, thirty youth with visual impairments and 1:1 professional preparation students (coaches) took part in a three-month virtual physical activity program. A total of 11 coaches took part in 2 focus groups, and 10 of the participants were interviewed about their experiences in this unique practicum. Findings in this three-month program revealed four themes: (1) friendship, (2) self-determination, (3) goal setting, and (4) barriers. The results of the qualitative inquiry indicate that a virtual practicum program can have a positive effect on both the participants and the professional preparation students. Virtual programs should also be aware of barriers to implementing an effective program to benefit all parties

Exploring the Experiences of Runners with Visual Impairments and Sighted Guides

: Running is a popular sport, and, with simple modifications, it can be accessible for individuals with visual impairments, particularly with a sighted running guide. The purpose of this study is to examine the experiences of runners with visual impairments and sighted running guides. Adopting a descriptive qualitative approach to guide data collection analysis and interpretation, seven runners with visual impairments and four sighted running guides were recruited and interviewed. The analysis identified four major themes: (1) benefits, (2) barriers, (3) advocacy, and (4) communication. The identified themes illustrate the influence of participation in running on the health and relationships of the runners with visual impairments, the barriers that exist to participation, and the advocacy and communication needed to overcome those barriers

Teaching for Black and Brown Lives: The Importance of Ethnic Studies Curriculum in the Education Success of Black and Latinx Students

This study identifies school policies and practices that create a gap in support for Ethnic Studies for high school graduation, college graduation, and teacher licensures. The first method was interviewing specific stakeholders through zoom who were in the position for the purpose of the research. The interviewed participants answered questions about the policies related to Ethnic studies, practice school policies, and implications of the ratification of Ethnic study policies in Nevada. The second method was analyzing Nevada state and Department of Education policies relating to teacher education. Interpreting how UNLV teacher licensure programs apply those policies in the preparation curriculum. Results from the methods were initial findings were 75% of the student population in CCSD are students of color, but there are still limited clubs that surround racialized experiences. Although students who participated in racial/ethnic club activities led to more enrollment in elective courses. Ethnic studies are considered along with social studies and “diversity studies”, which need to be differentiated from one another. Ethnic study courses can be a valuable enhancement to build cross-racial solidarity and create opportunities to make sense of school experiences. It is critical to make a foundation for success for Students of Color and Families of color in many schools and communities in CCSD.https://digitalscholarship.unlv.edu/durep_lightning/1003/thumbnail.jp

Introduction and Validation of the American Urological Association Basic Laparoscopic Urologic Surgery Skills Curriculum

Abstract Background and Purpose: The Fundamentals of Laparoscopic Surgery (FLS?) skills curriculum has validity evidence supporting use for assessing laparoscopic skills for general surgeons. As charged by the American Urological Association (AUA) Laparoscopy, Robotic, and New Surgical Technology Committee, we sought to develop and validate a urology-specific FLS, referred to as the Basic Laparoscopic Urologic Surgery (BLUS?) skills curriculum. The psychomotor component consists of three existing FLS tasks and one new clip-applying task. Materials and Methods: An animate renal artery model was designed for a clip-applying skills task. We assessed the acceptability and construct validity of using BLUS for basic laparoscopic skills assessment for urologists. A cohort of practicing urologists, fellows, residents, and medical students completed the tasks at the AUA Annual Meetings in 2010 and 2011. Results: All exercises were acceptable and demonstrated excellent face and content validity (>4.5/5 on a five-point Likert scale). Practicing clinical urologists (N=81) outperformed residents and medical students (N=35) in time to completion of circle cut (P3 laparoscopic procedures per week were faster at the peg-transfer exercise (P3 procedures (0.57) per week (P<0.01). Conclusions: All exercises including the novel clip-applying model demonstrated good acceptability and evidence of construct validity (face, content, concurrent and convergent validity) for assessment of basic laparoscopic skill for urologic surgeons.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98447/1/end%2E2011%2E0414.pd

Experimental Philosophy--An Emerging Discipline

This poster will explain the nature of a newly emerging field in philosophy called experimental philosophy (“X-phi”) and its presence on Boise State’s campus. BSU’s X-phi group operates via gathering data from “everyday” people, sorting and statistically analyzing the data, then reviewing trends identified people’s intuitions about certain concepts (e.g. know-how, intentional action, moral correctness, etc.). We are exploring the concept of Honesty—a concept that has, to date, not been adequately analyzed. To distinguish theories developed as a result of this research, X-phi employs the term “folk theory”, literally referring to the theory that the majority of people are found to hold. It’s then interdisciplinarily informative determine where these folk theories match up, or fail to, with existing philosophical theories. X-phi is still establishing itself in the greater academic community, but is proving its worth; philosopher and professor at Tufts University, Daniel Dennett, acknowledges in a recently published book review that “some of the work has yielded interesting results that certainly defy complacent assumptions common among philosophers.” BSU’s X-Phi group has been active on campus for two years; this poster will report the group’s evolution, current work, and explain what X-Phi is in general

Association of Maternal Immunity with Rotavirus Vaccine Immunogenicity in Zambian Infants

IntroductionLive attenuated oral vaccines against rotavirus (RV) have been shown to be less efficacious in children from developing countries. Reasons for this disparity are not fully understood. We assessed the role of maternal factors including breast milk RV-specific IgA, transplacentally acquired infant serum RV-specific IgG and maternal HIV status in seroconversion among Zambian infants routinely immunized with Rotarix™ (RV1).Methods420 mother-child pairs were recruited at infant age 6–12 weeks in Lusaka. Clinical information and samples were collected at baseline and at one month following the second dose of RV1. Determination of breast milk RV-specific IgA and serum RV-specific IgA and IgG was done using standardized ELISA. Seroconversion was defined as a ≥ 4 fold rise in serum IgA titre from baseline to one-month post RV1 dose 2, while seropositivity of IgA was defined as serum titre ≥ 40 and antibody variables were modelled on log-base 2. Logistic regression was used to identify predictors of the odds of seroconversion.ResultsBaseline infant seropositivity was 25.5% (91/357). The seroconversion frequency was 60.2% (130/216). Infants who were IgA seropositive at baseline were less likely to seroconvert compared to their seronegative counterparts (P = 0.04). There was no evidence of an association between maternal HIV status and seroconversion (P = 0.25). Higher titres of breast milk rotavirus-specific IgA were associated with a lower frequency of seroconverson (Nonparametric test for trend Z = -2.84; P<0.01): a two-fold increase in breast milk RV-specific IgA titres was associated with a 22% lower odds of seroconversion (OR = 0.80; 95% CI = 0.68–0.94; P = 0.01). There was seasonal variation in baseline breast milk rotavirus-specific IgA titres, with significantly higher GMTs during the cold dry months (P = 0.01).ConclusionLow immunogenicity of RV1 vaccine could be explained in part by exposure to high antibody titres in breast milk and early exposure to wild-type rotavirus infections. Potential interference of anti-RV specific IgA in breast milk and pre-vaccination serum RV specific-IgA and IgG titres with RV1 seroconversion and effectiveness requires further research

Annotated Bibliography of Research in the Teaching of English (2009)

This is the publisher's version, also found at http://search.proquest.com/docview/215343848/13E80C2B60056B43EE4/5?accountid=1455