Reproductive Biology of the Tiger Shark in the Western Atlantic Ocean

Although tiger sharks are an important apex predator in many ecosystems, little is known about their reproduction. The goal of this study was to determine the size-at-maturity and the reproductive seasonality of tiger sharks in the western Atlantic Ocean. This was achieved using a combination of ultrasonography and measurements of plasma hormone concentrations; in particular, testosterone for males and estradiol and progesterone for females. Steroid hormone concentrations were measured using chemiluminescent assays (CLIA). Maturity was also examined through histology of reproductive organs in females and clasper calcification in males. Females were found to mature between 270 and 310 cm total length and males were found to mature between 260 and 300 cm total length. Mating was determined to occur in October/November, based on the presence of mating wounds on females and increased concentrations of testosterone in males. Some females were shown to exhibit increased plasma estradiol concentrations also during October/November; however, we do not believe that ovulation takes place until May or June based on ultrasonography data. This suggests a period of sperm storage although histological examination of the oviducal gland was not able to confirm this. Ultrasonography data, showing increasing embryo size over the course of a year, and data on minimum size of tiger sharks caught in longline surveys suggested that parturition occurs between June and September with pups being born as small as 56 cm fork length. The findings from this study show that some tiger sharks reach reproductive maturity at sizes smaller than what has been previously suggested. Additionally, the possibility of tiger sharks storing sperm suggests that their reproductive cycle is a minimum of two years long and could be up to three years in duration. This information is important for management of the species in the future. Additionally, this study adds to the limited knowledge about reproduction of elasmobranchs and how patterns of reproductive steroids can correlate with different reproductive events

The social life of placebos: proximate and evolutionary mechanisms of biocultural interactions in Asante medical encounters

The Social Life of Placebos is an interdisciplinary study of the evolution of placebogenic responses – beneficial ones activated by psychosocial triggers -- and their elicitation in Asante medical contexts. Based on an extensive literature review in social, cultural, and medical studies and over 26 months of intensive research in rural Ghana, West Africa, it examines the therapeutic efficacy of Asante medical encounters by analyzing rites of care-giving within an evolutionary framework. Section 1 investigates why evolutionary processes appear to have made human physiology susceptible to psychosocial manipulation, what the health consequences of that susceptibility are in modern environments, and how culturally specific expectations and healing rituals might dampen or amplify that susceptibility. Because of key transitions in human evolution, the fitness consequences of sociality have increased rapidly and created the conditions whereby endogenous mechanisms have become responsive to sociocultural conditions. This explanation helps us better understand why culturally specific rituals can elicit powerful beneficial (placebo) and adverse (nocebo) physiological responses. Using a mixed methodology of physiological data and ethnographic case studies collected from hundreds of Asante medical encounters, Section 2 illuminates evolutionary and proximate processes in Asante contexts of care-giving and healing rituals in detailed chapters on pain, emotion, and stress. It examines the social and cultural resources and techniques that Asante health practitioners rely on for pain management in contexts where no pain medication is available. It analyzes the biocultural interactions that can take place when healers modify patient perceptions, emotions, and expectations. The dissertation concludes with biometric evidence that Asante indigenous ritual healing ceremonies actually promote significant entrainment and relaxation effects

Epoxy Composites Using Wood Pulp Components as Fillers

The components of wood, especially lignin and cellulose, have great potential for improving the properties of polymer composites. In this chapter, we discuss some of the latest developments from our lab on incorporating wood-based materials into epoxy composites. Lignosulfonate was used as a flame retardant and cellulose nanocrystals were used as reinforcing materials. Lignosulfonate will disperse well in epoxy, but phase separates during curing. An epoxidation reaction was developed to immobilize the lignosulfonate during curing. The lignosulfonate–epoxy composites were characterized using microcombustion and cone calorimetry tests. Cellulose also has poor interfacial adhesion to hydrophobic polymer matrices. Cellulose fibers and nanocrystals aggregate when placed in epoxy resin, resulting in very poor dispersion. The cellulose nanocrystal surface was modified with phenyl containing materials to disrupt cellulose interchain hydrogen bonding and improve dispersion in the epoxy resin. The cellulose nanocrystal – epoxy composites were characterized for mechanical strength using tensile tests, water barrier properties using standardized water absorption, glass transition temperatures using differential calorimetry, and aggregation and dispersion using microscopic techniques

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

The Reeve in Late Anglo-Saxon England

The aim of this research is to build a picture of the reeve in late Anglo-Saxon England. This little-understood figure has traditionally received limited attention in scholarship, and this study attempts to rectify this, and to shed light upon this official and his impact on English society. Chapter One explores the nature and implications of the reeve’s role as an administrator in Anglo-Saxon government. The law codes emerge as a key source in determining how legislators saw the reeve fitting into and contributing to the mechanisms of the administration. Chapter Two looks at the reeve’s status in late Anglo-Saxon society, as well as both the nature of the reeve’s relationship with the king, as well as how he acted as a counterbalance to the powerful and influential ealdormen in the localities. Taking a step away from the reeve as a royal agent, Chapter Three focuses on the reeve as an estate manager for the private aristocratic lord. The nature of the reeve’s work on the late Anglo-Saxon estate, as well as how he was rewarded for that work, is explored. The resultant picture not only broadens our knowledge of the private reeve, but also how he fit into tenth- and eleventh-century English society. Chapter Four explores the manner in which the reeve is presented in late Anglo-Saxon homiletic discourse. Arguably, the increasing number of negative references to the reeve in these moralizing texts is reflective of his growing prominence and influence in late Anglo-Saxon England. The work of Archbishop Wulfstan of York is also examined: it is argued that despite the plethora of moralizing references to the reeve at this time, Wulfstan’s thinking represented a departure from this trend. The archbishop crafted a role for the reeve that was integral to the realization of his vision of a “holy society”

The Role of Genetic Mutations in Mitochondrial-Driven Cancer Growth in Selected Tumors: Breast and Gynecological Malignancies

There is an increasing understanding of the molecular and cytogenetic background of various tumors that helps us better conceptualize the pathogenesis of specific diseases. Additionally, in many cases, these molecular and cytogenetic alterations have diagnostic, prognostic, and/or therapeutic applications that are heavily used in clinical practice. Given that there is always room for improvement in cancer treatments and in cancer patient management, it is important to discover new therapeutic targets for affected individuals. In this review, we discuss mitochondrial changes in breast and gynecological (endometrial and ovarian) cancers. In addition, we review how the frequently altered genes in these diseases (BRCA1/2, HER2, PTEN, PIK3CA, CTNNB1, RAS, CTNNB1, FGFR, TP53, ARID1A, and TERT) affect the mitochondria, highlighting the possible associated individual therapeutic targets. With this approach, drugs targeting mitochondrial glucose or fatty acid metabolism, reactive oxygen species production, mitochondrial biogenesis, mtDNA transcription, mitophagy, or cell death pathways could provide further tailored treatment