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INVESTIGATING SOLVENT EFFECTS ON CRYSTALLIZATION KINETICS
No full textThe use of crystallization for separation is not a recent phenomenon. However, the development of efficient crystallization processes is continually being challenged by the complexity and high cost of new drug substances, coupled with stringent regulatory requirements, which add to the uncertainty surrounding drug launches by pharmaceutical enterprises. Accurate characterization of crystallization kinetics is a key step in crystallizer design, which can be influenced by several factors, including process conditions, scale, and the measurement techniques used for tracking particle evolution. These factors often lead to inconsistencies between kinetic studies, hindering rapid implementation within industrial contexts. This thesis presents a case study on crystallization kinetics, focusing on how solvent dependency of nucleation and growth parameters are influenced by process and operating modes. Nucleation and growth parameters were estimated using semi empirical kinetics models coupled to population balance equations for a selected pharmaceutical ingredient in a binary solvent mixture at 5 mL solute-solvent suspension volume. This was followed by a scale-up study using a continuous antisolvent crystallization at 300 mL volume. The study provides an approach for characterizing crystallization kinetics under scale-down conditions via kinetics trends, minimizing time and resource demands during process development, while highlighting differences between crystallization methods and process analytical technologies (PAT)
Ion-DNA Interactions as a Key Determinant of Uracil DNA Glycosylase Activity.
Get PDFBecause of their ubiquitous presence, ions interact with numerous macromolecules in the cell and affect critical biological processes. Here, we discuss how cations including Mg2+ alter the enzymatic activity of a DNA glycosylase by tuning its affinity for DNA. The response of uracil DNA glycosylase (UNG2) to Mg2+ ions in solution is biphasic and paradoxical, where low concentrations of the ion stimulate the enzyme, but high concentrations inhibit the enzyme. We analyzed this phenomenon by modeling experimental data with a statistical framework that we empirically derived to understand molecular systems that display biphasic behaviors. Parameters from our statistical model indicate that DNA substrates are nearly saturated with cations under ideal conditions for UNG2 activity. However, the enzyme slows rather abruptly when the ionic content becomes too low or too high due to changes in the electrostatic environment that alter protein affinity for DNA. We discuss how ion occupancy on DNA is dependent on DNA length; thus, the sensitivity of UNG2 to cations is also dependent on DNA length. Finally, we found that Mg2+-induced changes in DNA base stacking and dynamics have minimal effects on UNG2, as these outcomes occur at ion concentrations that are much lower than is required for efficient enzyme activity. Altogether, our work demonstrates how cation–DNA interactions, which are likely common in the nucleus, are a key determinant of uracil base excision repair mediated by UNG2
Mechanisms Underlying Estrous Cycle-Dependent Changes in Incubated Cocaine Craving
No full textCues associated with cocaine use are one of the most common relapse triggers and understanding what promotes cue-induced cocaine craving and relapse is a critical question in the field. Human studies have shown that these measures are impacted by fluctuations in ovarian hormone levels, as higher levels of estradiol promote cue-induced cocaine craving in women while higher levels of progesterone reduce craving in both sexes. Enhanced or incubated cue-induced cocaine seeking or craving also changes across the rodent reproductive (estrous) cycle as levels of estradiol and progesterone fluctuate, with enhanced seeking behavior observed during the estrus stage of the cycle. However, how ovarian hormones impact cocaine craving and relapse vulnerability and the molecular underpinnings driving these changes remain unclear. Here we found that administering hormone modulators to block estrogen and progesterone receptors during proestrus, when ovarian hormones are reaching peak levels, does not attenuate the enhanced cue-induced cocaine seeking behavior exhibited during estrus. However, we found that acutely inhibiting estrogen receptors only during estrus does attenuate enhanced cue-induced cocaine seeking behavior, indicating that rapid estrogen receptor signaling may be potentiating this behavior. Further, we found estrous cycle-dependent changes in estrogen receptor and AMPA receptor subunit expression in the basolateral amygdala of cocaine-exposed rats, a region known to mediate incubated cue-induced cocaine seeking. Together, these findings begin to parse apart the role of ovarian hormones in enhanced cue-induced cocaine seeking behavior and identify potential mechanisms underlying these effects
INFLUENCE OF THE EXTRACTION SOLVENT AND SYNTHESIS METHODS ON THE PROPERTIES OF BIRCH BARK EXTRACT-BASED THERMOSETS FOR ALUMINUM AND WOOD COATINGS
No full textThe vast array of complex organic molecules contained within Birch Bark Extract (BBE) provides the building blocks to make it a potential bio-based alternative towards replacing petroleum-based polymers for selected coatings applications. However, the isolation of these individual molecules is costly and complex, making it unrealistic to develop cost-effective bio-based polymers at commercial scales. Thus, this thesis focuses on developing thermosets from birch tree bark in cost-efficient ways using different extraction solvents (i.e., chloroform and ethanol), bio-based diacids (i.e., C9, C12, and C18 diacids) and homogenization methods (i.e., oil bath, single-screw, and twin-screw extruders). The thermal characteristics of the resulting polymers were evaluated via DSC and TGA as favorable thermal properties are essential to develop polyesters with optimal and tailored properties for coatings applications. The thermal attributes of the BBE thermosets were impacted by solvent choice and synthesis technique. The potential utilization of these thermosets as bio-based films for wood and aluminum protection was assessed via cross-hatch adhesion, impact force resistance, contact angle measurement, mandrel bending, weather resistance, and pendulum hardness tests. The BBE-based aluminum and wood films exhibited outstanding adhesion to the substrates as well as favorable coatings properties
BURNING OUT AT THE MARGINS OF A TRANSITION: A HEURISTIC INQUIRY OF WOMEN ADJUNCT FACULTY AT A CARNIGIE CLASSIFIED LEVEL TWO RESEARCH (R2) UNIVERSITY
No full textWomen contingent faculty play an integral role in the success of higher education. Yet many find themselves working in environments that fail to recognize and value their potential as both educators and scholars. As institutions of higher education evolve and pursue prestige, women contingent faculty will be forced to contend with environments that remain inherently gendered, unsupportive, and conducive to burnout. The purpose of this qualitative heuristic inquiry was to understand the lived experiences of women contingent faculty who experienced burnout while employed for a transitioning Carnegie Classified level 2 research (R2) institution of higher education. Further, this research sought to understand and give a voice to the lived experiences of a community that is often silenced, unvalued, restricted, and yet called up to be the backbone of higher education. Three themes were identified that highlighted the expressed experiences of participants which were clash of cultures, illusory trophy, and beleaguered belonging. These themes portray how women contingent faculty perceived the organizational culture as one marked by indifference, a lack of meaningful rewards, and a profound sense of disconnection and exclusion
Introduction to Literature Mapping Tools
Get PDFLearning objectives: Learn what is literature mapping Explore various literature mapping tools Learn new approaches to finding research beyond traditional databases
Literature mapping is a method for discovering and exploring connections among scholarly peer-reviewed articles on your research topic. It uses graphical methods to plot relationships among published scholarship (e.g., links via citations, authors, keywords, other descriptors). Literature mapping can help researchers see patterns that otherwise might not be evident. In this introductory workshop, Life Sciences Librarian Dan Kipnis, will present various literature mapping techniques and online tools (i.e. Elicit, Semantic Scholar, Connected Papers, Research Rabbit, and STORM) to help researchers discover scholarly literature beyond using traditional databases.
Skill levels for attendees: Little to no experience, Some experience
Software requirements: None
Workshop offered as part of Rowan University Libraries workshop series
An In Vivo Study of LNS8801, a GPER Agonist, in a Spontaneous Melanoma-Prone Mouse Model, TGS.
Get PDFMelanoma is the most aggressive and deadly form of skin cancer that arises from the transformation of melanocytes, the pigment producing cells of the skin. In the year 2024 there will be approximately 10,000 new cases of melanoma diagnosed and approximately 8,000 deaths attributed to melanoma in the United States. In this study we treated a group of male and female transgenic mice that spontaneously develop metastatic melanoma, TGS, with a G-protein-coupled estrogen receptor agonist LNS8801 to assess the efficacy on disease progression. A second group of male and female TGS mice was also exposed to UVB irradiation to mimic exposure to sunlight. Over the course of the 32-week experiment, visible images were taken by the small animal imaging IVIS system to track tumor progression, and blood and tissue samples were collected for molecular analyses. Results showed that sex-biased effects were observed in the efficacy of LNS8801 and that LNS8801 shows a UV-protective influence in both male and female TGS mice
Crossing the Chasm: Engaging Black Men Survivors of Gun Violence in Mental Health Services
Get PDFBACKGROUND: Despite being high risk for post-traumatic stress disorder, Black men survivors of gun violence, and particularly young men aged 18-24, seldom participate in mental health services after injury. The aim of this study was to identify barriers to participation in mental health services for this population.
METHODS: Over a 2-year period, 1 hour-long focus group was conducted with three counselors of the local hospital-based violence intervention program and 21 individual, semistructured in-depth interviews were held with Black men who were hospitalized for a firearm-related injury. All interviews were recorded and transcribed. Transcripts were coded using open coding and grounded theory methodology and ultimately grouped into themes using MAXQDA V.2022 software.
RESULTS: Median age of participants was 34 years (IQR=11). Barriers to participation revolved around competing priorities/stressors, expense, difficulty with trust and openness and the demands of street life. Motivating factors included cultural competence, persistence, availability, reliability and genuineness of the therapy staff. Most participants denied negative social stigma of therapy as a barrier but emphasized that the individual must value therapy to participate. Young, Black men were perceived as struggling with self and peer-imposed views of masculinity that conflicted with therapy participation.
CONCLUSION: Black men who have experienced violent firearm injury face strong social pressures that conflict with participation in mental health services. Programs must be integrated with other social services and be responsive to community conditions to be successful.
LEVEL OF EVIDENCE: IV
Effect of Time-Restricted Feeding on Anthropometric, Metabolic, and Fitness Parameters: A Systematic Review
Get PDFTime restricted feeding (TRF) as a form of intermittent fasting (IF) has gained popularity because its ability to reduce body mass (BM) without an emphasis on caloric restriction. However, how this dietary protocol may affect health, fitness, and performance in a relatively healthy cohort remains less clear. The purpose of this article was to systematically review the current literature concerning the effect of TRF on anthropometric, metabolic, and fitness parameters in normal-weight adults and overweight and obese individuals. A systematic search of English literature was conducted through databases including PubMed, CINAHL, and Google Scholar. The search was facilitated by using various combinations of key words related to nutritional interventions, i.e., IF and TRF, and outcomes of interest, i.e., BM, body composition, glucose, insulin, lipid, fitness, and performance. The article selection was made based on the inclusion and exclusion criteria concerning the participants’ characteristics, study design, intervention protocols, and targeted dependent variables. Twenty-three full-text longitudinal randomized and nonrandomized controlled studies were selected for this review. Our analysis indicates that TRF can reduce BM and improve nutrient metabolism in both normal- and over-weight individuals. TRF does not appear to alter protein synthesis and fat-free mass nor hamper aerobic fitness and muscular performance among physically active individuals including athletes. In conclusion, TRF as a more easily adaptable form of IF is a promising dietary approach to improving body composition and metabolic health while maintaining fitness and muscular function. However, more research is needed before this dietary protocol can be fully recommended for athletes especially those competing in sports that demand strength and power