Spinodal-assisted crystallization in polymer melts

Recent experiments in some polymer melts quenched below the melting temperature have reported spinodal kinetics in small-angle x-ray scattering before the emergence of a crystalline structure. To explain these observations we propose that the coupling between density and chain conformation induces a liquid-liquid binodal within the equilibrium liquid-crystalline solid coexistence region. A simple phenomenological theory is developed to illustrate this idea, and several experimentally testable consequences are discussed. Shear is shown to enhance the kinetic role of the hidden binodal

Nitrogen and Fiber Digestion in Sheep Fed Fresh-Frozen and Field-Dried High and Low Tannin Sericea Lespedeza

Field-drying reduces extractable condensed tannin (CT) of sericea lespedeza [Lespedeza cuneata (Dum-Cours) G. Don], but effects on specific bound and unbound forms of CT and the relationship to protein and fiber digestion in ruminants are unclear. Intake and digestibility of fresh-frozen and field-dried high- and low-tannin sericea were investigated in a feeding trial with sheep (Ovis spp.). Field-drying had no effect on crude protein (CP) and fiber content of sericea, but shifted CT from extractable to bound forms. Digestion coefficients for CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) were lower for high-tannin sericea than the low-tannin type. Field-drying had no effect on fiber digestibility but increased CP digestibility and N retention in sheep fed high-tannin forage. Apparent digestion of CT was high for all treatments, but this is likely due to difficulty in analyzing CT in fecal material. Nutritional effects of CT in sericea lespedeza are related to both total CT and proportion of bound and unbound CT in the forage

Relationship Between Grit with Academic Performance and Attainment of Postgraduate Training in Pharmacy Students

Objective. To determine if Grit-S scores correlate with academic success in a doctor of pharmacy (PharmD) program, as well as the pursuit and attainment of pharmacy postgraduate (residency or fellowship) training. Methods. A 28-item survey was administered to third- and fourth-year (P3 and P4) pharmacy students. Variables queried included Grit-S score, demographics, pharmacy experience prior to the PharmD program, and factors that may affect academic performance during didactic coursework. Didactic coursework GPA was used as a surrogate for academic success. Information about pursuit and attainment of a postgraduate training position was also documented and used in the analyses. Results. There was no significant correlation between Grit-S scores and variables related to academic success. However, students were more likely to pursue postgraduate training with higher academic success and higher Grit-S. Lastly, students with higher Grit-S were also more likely to obtain a postgraduate training position. Conclusion. Grit-S scores correlated with the pursuit and successful attainment of postgraduate training, but not with academic success during the didactic years of a PharmD program

Investigating the Fibrillar Ultrastructure and Mechanics in Keloid Scars Using In Situ Synchrotron X-ray Nanomechanical Imaging

Fibrotic scarring is prevalent in a range of collagenous tissue disorders. Understanding the role of matrix biophysics in contributing to fibrotic progression is important to develop therapies, as well as to elucidate biological mechanisms. Here, we demonstrate how microfocus small-angle X-ray scattering (SAXS), with in situ mechanics and correlative imaging, can provide quantitative and position-resolved information on the fibrotic matrix nanostructure and its mechanical properties. We use as an example the case of keloid scarring in skin. SAXS mapping reveals heterogeneous gradients in collagen fibrillar concentration, fibril pre-strain (variations in D-period) and a new interfibrillar component likely linked to proteoglycans, indicating evidence of a complex 3D structure at the nanoscale. Furthermore, we demonstrate a proof-of-principle for a diffraction-contrast correlative imaging technique, incorporating, for the first time, DIC and SAXS, and providing an initial estimate for measuring spatially resolved fibrillar-level strain and reorientation in such heterogeneous tissues. By application of the method, we quantify (at the microscale) fibrillar reorientations, increases in fibrillar D-period variance, and increases in mean D-period under macroscopic tissue strains of ~20%. Our results open the opportunity of using synchrotron X-ray nanomechanical imaging as a quantitative tool to probe structure–function relations in keloid and other fibrotic disorders in situ

Minutes 1876

https://place.asburyseminary.edu/freemethodistminutesyearbooks/1014/thumbnail.jp

Efficacy and Safety of MED2005, a Topical Glyceryl Trinitrate Formulation, in the Treatment of Erectile Dysfunction: A Randomized Crossover Study

Background: Current treatments for erectile dysfunction (ED) have some limitations. // Aim: This study evaluated the efficacy and tolerability of MED2005, a 0.2% glyceryl trinitrate topical gel, formulated into an enhanced absorption topical delivery system (DermaSys), administered on demand, in the treatment of ED. // Methods: This randomized, double-blinded, placebo-controlled, phase II crossover trial involved 232 men with ED (231 treated, 230 assessed for efficacy) and their partners. After a 4-week run-in period, patients were randomized to 1 of 2 treatment sequences, MED2005-placebo or placebo-MED2005. Each treatment was given for 4 weeks, separated by a 1-week washout interval. Efficacy was assessed by the International Index of Erectile Function (IIEF), the Sexual Encounter Profile, a Global Assessment Questionnaire (GAQ), and specific questions about the onset and offset of action and treatment preferences (patients and partners). // Outcomes: The primary outcome measure was the IIEF erectile function domain (IIEF-EF) score. Other efficacy assessments were secondary outcomes. // Results: The mean baseline IIEF-EF score was 17.1 (SD = 5.7), and this increased to 19.6 (SD = 7.5) after MED2005 treatment and 18.5 (SD = 6.7) after placebo (P = .0132). Overall, 23.1% of patients showed a clinically relevant (≥4-point) increase in IIEF-EF scores after treatment with MED2005 only compared with 14.5% who responded after MED2005 and placebo, 14.0% who responded after placebo only, and 48.4% who did not respond after either treatment (P = .0272). MED2005 also was associated with significant improvements compared with placebo in the other IIEF domains, and this was consistent with patients’ and partners’ responses to the GAQ. For all assessments, significant effects of MED2005 were seen primarily in patients with mild ED. The start of erection was noticed within 5 and 10 minutes in 44.2% and 69.5%, respectively, of all intercourse attempts with MED2005. Patients and partners showed significant preferences for MED2005 over placebo. The most commonly reported adverse events during MED2005 treatment were headache (patients, n = 18 [7.9%]; partners, n = 3 [1.3%]) and nasopharyngitis (patients, n = 13 [5.7%]; partners, n = 2 [0.9%]). // Clinical Implications: These findings suggest that topical glyceryl trinitrate could be a useful treatment option in ED. // Strengths and Limitations: Strengths of this study include the use of a validated outcome measure. Limitations include the use of only 1 dosage. // Conclusion: Further studies are warranted to investigate the efficacy of topical glyceryl trinitrate to include higher doses, thereby improving clinical significance, especially in cases of moderate and severe ED

4,10-Diall­yloxy-1,2,3,6b,7,8,9,12b-octa­hydro­perylene

In the title compound, C26H28O2, the central atoms are coplanar, with the –CH2—CH2– links of the cyclo­hexene groups lying to either side of the plane and with the diall­yloxy residues twisted out of this plane [C—C—O—C torsion angles = 16.6 (3) and −13.9 (3)°]. In the crystal structure, mol­ecules are connected into chains propagating in [100] via C—H⋯π inter­actions

The hierarchical response of human corneal collagen to load

Fibrillar collagen in the human cornea is integral to its function as a transparent lens of precise curvature, and its arrangement is now well-characterised in the literature. While there has been considerable effort to incorporate fibrillar architecture into mechanical models of the cornea, the mechanical response of corneal collagen to small applied loads is not well understood. In this study the fibrillar and molecular response to tensile load was quantified using small and wide angle X-ray scattering (SAXS/WAXS), and digital image correlation (DIC) photography was used to calculate the local strain field that gave rise to the hierarchical changes. A molecular scattering model was used to calculate the tropocollagen tilt relative to the fibril axis and changes associated with applied strain. Changes were measured in the D-period, molecular tilt and the orientation and spacing of the fibrillar and molecular networks. These measurements were summarised into hierarchical deformation mechanisms, which were found to contribute at varying strains. The change in molecular tilt is indicative of a sub-fibrillar “spring-like” deformation mechanism, which was found to account for most of the applied strain under physiological and near-physiological loads. This deformation mechanism may play an important functional role in tissues rich in fibrils of high helical tilt, such as skin and cartilage

Anthelmintic Effects of Sericea Lespedeza Hay Fed to Goats Infected With \u3cem\u3eHaemonchus Contortus\u3c/em\u3e

Infection with gastrointestinal nematodes (GIN), particularly Haemonchus contortus, is the major hindrance to economic goat production in the southern USA. Grazing forages high in condensed tannins (CT) or adding purified CT to the diet has been shown to reduce numbers of parasite eggs in sheep and goat faeces (Min & Hart, 2003). An alternative to grazing is feeding hay from CT-containing forages to livestock to reduce the effects of GIN (Shaik et al., 2004). The purpose of the current study was to test potential anthelmintic effects of feeding sericea lespedeza [(Lespedeza cuneata (Dum.-Cours.) G. Don] hay to goats