Gaseous diffusion in glassy polymers

A model for gaseous diffusion in glassy polymers is developed with a view to accounting for the observations made in dual sorption and certain other phenomena in polymers below their glass transition temperature. In this paper a preliminary study of the effects of both the immobilizing mechanism and the generalized diffusion mechanism on travelling waves and the diffusive wavefronts is made

A feed-restriction model to identify factors responsible for fescue toxicosis-induced reduction in food intake [abstract]

Abstract only availableFescue toxicosis results from intake of ergopeptine alkaloids derived from a fungus (Neotyphodium coenophialum ) in tall fescue, and produces reduced productivity. Contributors to this reduction are decreased feed intake and growth. There have been few attempts to characterize these changes. A study was conducted to develop a model for this component using rats in a feed restriction experiment described previously by others. Each animal was trained over a minimum 11 d period to eat their entire daily ration from 1300-1500. This allows one to evaluate the effect of potential treatments more precisely by using a 2 hours rather than 24. Group I animals were first fed in this order an endophyte-free seed (E-) diet (ad libitum ), a restricted E- diet, a restricted endophyte-infected seed (E+) diet, and lastly an E- diet (ad libitum ). There was no decrease in feed intake (α= 0.05) from restricted E- to restricted E+ diets, but reduced growth while on E+ diet. Return to E- diet restored growth. A different routine was used with Group II. Rats were first fed ground commercial diet (ad libitum ), followed by restricted ground diet, restricted E- diet, and lastly restricted E+ diet. Initial exposure to restricted diet decreased feed intake and growth (α = 0.05), followed by partial recovery or adaptation over following 4 days. Shift to restricted E- produced no change in feed intake and a greater return of growth. Restricted E+ diet intake reduced feed intake and growth within 24 hours (α = 0.05). This reduction was stable over the entire 2 week period. These responses agree with previous studies using long-term ad libitum E+ treatment. This new model can now be used to identify mechanisms for fescue toxicosis-induced reduction in feed intake and growth, and develop potential treatments

Measurement of endothelial function and its clinical utility for cardiovascular risk

Over the past two decades, the central role of the endothelium in the initiation, progression, and clinical sequelae of atherosclerosis has been increasingly recognized. Assessment of the pathobiology of the endothelium and its ability to act as a potential therapeutic target remains an area of active research interest. Whilst endothelial function has been shown to be a marker for risk of cardiovascular events in high-risk groups, there remains considerable debate about the most appropriate way to assess this. We discuss the different clinical methods to assess endothelial function, focusing on flow-mediated dilatation (FMD) of the brachial artery, highlighting the importance of using a standardized methodology, as well as discussing the clinical limitations of using FMD in individuals

Post-Pandemic, Translational Research, and Indigenous Communities

It is well documented that American Indian/Alaska Native/Native Hawaiian/First Nations, known as Indigenous Peoples, have among the most significant health disparities in the world. Clinical services for these populations are typically underfunded, and Indigenous Peoples often have preexisting and co-occurring health conditions. These factors combined with a multitude of social inequities make Indigenous communities extremely susceptible to infectious diseases, including COVID- 19. This paper discusses perspectives on the post-pandemic frameworks and policies toward translational science as an approach to advance health promotion for community-based interventions, dissemination, and sustainability. The importance of exercising Indigenous self-determination, public health authority, and population health sovereignty is emphasized

Surveys of Stylisma Pickeringii var. Pattersonii (Convolvulaceae), its Associated Plant Species, and its Insect Visitors

Stylisma pickeringii var. pattersonii (Convolvulaceae) is endangered in Illinois and Iowa, and occurs in scattered populations in other states. During 1999 and 2000, two insect species previously unreported from Illinois were observed visiting its flowers. This study was undertaken to survey additional insect visitors, as well as to characterize the plant community where S. pickeringii occurs. The objectives were to survey: 1) floral traits (anthesis and flower density) of S. pickeringii, 2) associated plant species, and 3) insect visitor characteristics. Floral traits were determined and associated plant species surveyed in Mason County (degraded hay field on private property) and Henderson County (dry sand prairie at the Big River State Forest), Illinois. Insects visiting flowers were collected at 10:00 a.m., 12:30 p.m., and 3:00 p.m. during June, July, and August in 2001 and 2002. Individual flowers lasted one day and remained open for 6–8 hours. Peak flowering occurred from early to the middle of July when S. pickeringii was the dominant species in flower. Henderson County contained a greater diversity of native plant species with less bare ground and fewer non-native species than the Mason County site. Fortyseven insect species were observed visiting S. pickeringii flowers. Most frequent visitors were Apis mellifera (Hymenoptera: Apidae), Bombylius fraudulentus (Diptera: Bombyliidae), and Heterostylum croceum (Diptera: Bombliidae). The diversity of visiting insects was higher earlier than later in the day, in July and August than June, and in Henderson than Mason County

Decreased soluble guanylate cyclase contributes to cardiac dysfunction induced by chronic doxorubicin treatment in mice

Aims: The use of doxorubicin, a potent chemotherapeutic agent, is limited by cardiotoxicity. We tested the hypothesis that decreased soluble guanylate cyclase (sGC) enzyme activity contributes to the development of doxorubicin-induced cardiotoxicity. Results: Doxorubicin administration (20 mg/kg, intraperitoneally [IP]) reduced cardiac sGC activity in wild-type (WT) mice. To investigate whether decreased sGC activity contributes to doxorubicin-induced cardiotoxicity, we studied mice with cardiomyocyte-specific deficiency of the sGC alpha 1-subunit (mice with cardiomyocyte-specific deletion of exon 6 of the sGC alpha 1 allele [sGC alpha 1(-/-CM)]). After 12 weeks of doxorubicin administration (2 mg/kg/week IP), left ventricular (LV) systolic dysfunction was greater in sGC alpha 1(-/-CM) than WT mice. To further assess whether reduced sGC activity plays a pathogenic role in doxorubicin-induced cardiotoxicity, we studied a mouse model in which decreased cardiac sGC activity was induced by cardiomyocyte-specific expression of a dominant negative sGC alpha 1 mutant (DNsGC alpha 1) upon doxycycline removal (Tet-off). After 8 weeks of doxorubicin administration, DNsGC alpha 1(tg/+), but not WT, mice displayed LV systolic dysfunction and dilatation. The difference in cardiac function and remodeling between DNsGC alpha 1(tg/+) and WT mice was even more pronounced after 12 weeks of treatment. Further impairment of cardiac function was attenuated when DNsGC alpha 1 gene expression was inhibited (beginning at 8 weeks of doxorubicin treatment) by administering doxycycline. Furthermore, doxorubicin-associated reactive oxygen species generation was higher in sGC alpha 1-deficient than WT hearts. Innovation and Conclusion: These data demonstrate that a reduction in cardiac sGC activity worsens doxorubicin-induced cardiotoxicity in mice and identify sGC as a potential therapeutic target. Various pharmacological sGC agonists are in clinical development or use and may represent a promising approach to limit doxorubicin-associated cardiotoxicity

The Ursinus Weekly, February 12, 1951

New high set by B-list group as 106 qualify • Y schedules chats, conducts retreat • Paynter-Keller production scores hit in Curtain Club group presentation • Play contest in progress; May Day heads named • Alumna to speak at girls\u27 Color Day program Thursday • Eight enter Ursinus for Spring term • Forum to feature Indian editor at next session • Speak Easy title of Ruby show • TV auditions slated • 3 graduate school test dates released • Ursinus to enter competition in intercollegiate bridge • Dr. Miller to give IRC summary of Department of State conferences attended in recent weeks • Washington trip planned by PAC • Meistersingers give concert • Editorial: Attend forums? • Senior class discusses Ruby and after-game record dance • Red Cross to organize • Juniors discuss bands • French Club to present dance Wednesday night in music studio • Thespians to discuss play • Dictionary of Folklore and Legend includes work of Dr. Phillips on Pennsylvania Dutch • Behind-scenes Dean handles transcripts, records dating from 1873, in routine work • Men reveal resignation toward draft situation • Alumnae back and Duryea\u27s got \u27em; Grads return in role of preceptresses • Coach Seeders drives Bruins toward coveted Middle Atlantic championship • Grizzlies win and lose in non-league contests • Bears edge Blue Hens for loop lead, 62-60 • Mermaids triumph over Drexel, 35-22 • Belles bag first over Bryn Mawr • Brodbeck I & II, Stine lead • Dr. Baker chooses poetry of A. E. Housman for readinghttps://digitalcommons.ursinus.edu/weekly/1558/thumbnail.jp