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Pinnipeds (seals, sea lions, walruses, and their fossil relatives) are one of the most successful mammalian clades to live in the oceans. Despite a well-resolved molecular phylogeny and a global fossil record, a complete understanding of their macroevolutionary dynamics remains hampered by a lack of formal analyses that combine these 2 rich sources of information. We used a meta-analytic approach to infer the most densely sampled pinniped phylogeny to date (36 recent and 93 fossil taxa) and used phylogenetic paleobiological methods to study their diversification dynamics and biogeographic history. Pinnipeds mostly diversified at constant rates. Walruses, however, experienced rapid turnover in which extinction rates ultimately exceeded speciation rates from 12 to 6 Ma, possibly due to changing sea levels and/or competition with otariids (eared seals). Historical biogeographic analyses, including fossil data, allowed us to confidently identify the North Pacific and the North Atlantic (plus or minus Paratethys) as the ancestral ranges of Otarioidea (eared seals + walrus) and crown phocids (earless seals), respectively. Yet, despite the novel addition of stem pan-pinniped taxa, the region of origin for Pan-Pinnipedia remained ambiguous. These results suggest further avenues of study in pinnipeds and provide a framework for investigating other groups with substantial extinct and extant diversity. [ABSTRACT FROM AUTHOR]

This article examines the penis bone, or baculum, of the leopard seal and its implications for understanding the species' reproductive strategies. The researchers studied the soft tissue and skeletal anatomy of an adult male leopard seal through dissection and CT scanning. They found that the leopard seal's penile anatomy is similar to other seals, and that the baculum undergoes shape changes during puberty. This study provides valuable insights into the reproductive anatomy of leopard seals, but further research is needed to understand the variation in baculum morphology and the reproductive anatomy of female leopard seals. [Extracted from the article]

Describes a seminar program at the University of Maryland Dental School, which uses books, short stories, and films that integrate human values into dental education, specifically in pediatric dentistry, for residents, clerks, and faculty. Results of initial evaluation and changes in the program over time are detailed. (DB)

The extant pig‐nosed turtle (Carettochelys insculpta), persisting in far northern Australia and southern New Guinea, is the last surviving member of Carettochelyidae and the only non‐Gondwanan freshwater turtle lineage in Australia. Despite having a global fossil record dating to the Cretaceous, the absence of carettochelyid fossils from Australia has implied a relatively recent colonization of this landmass. Here we report an upper Miocene to lower Pliocene carettochelyid fossil from Beaumaris, Victoria, in south‐eastern Australia. This record is the most southerly occurrence of the clade Carettochelyidae. The presence of carettochelyids in southern Australia, and a discontinuous record of trionychids (soft‐shell turtles) in the Cenozoic of Queensland, suggests at least two colonizations of Australia by Trionychia, pre‐dating the extant pig‐nosed turtle. This cryptic southern history of tropical soft‐shell and pig‐nosed turtles ended before the recent aridification of Australia, leaving the Gondwanan side‐necked turtles as the dominant turtle group in Australian freshwater ecosystems. Therefore, this singular fossil reveals a previously unknown shift in the diversity and evolutionary history of freshwater turtles in Australia. [ABSTRACT FROM AUTHOR]

Most of the diversity of extant southern true seals (Phocidae: Monachinae) is present in the Southern Ocean, but a poor fossil record means that the origin of this fauna remains unknown. Australia represents a large gap in the record bordering the Southern Ocean that could possibly inform on the origins of the extant Antarctic monachines, with most known fossils remaining undescribed. Here we describe the oldest Australian fossil pinniped assemblage, from the Late Miocene to the Early Pliocene of Beaumaris. Two fossils are referrable to Pinnipedia, five (possibly six) to Phocidae and a humerus is referrable to Monachinae. The humerus is not referrable to any extant tribe, potentially representing an archaic monachine. The description of this assemblage is consistent with the Neogene pinniped fauna of Australia being exclusively monachine before the arrival of otariids (fur seals and sea lions). The Beaumaris humerus, along with other Neogene phocids from the Southern Ocean margins, were smaller than their extant Antarctic relatives, possibly driven by longer food chains with less energy efficiency between trophic levels. This suggests that small archaic phocids potentially used the Southern Ocean as a means of dispersal before the arrival of extant Antarctic monachines. [ABSTRACT FROM AUTHOR]

Dentistry, like all professions, has always had ethical problems to contend with, including societal trust, flagrant advertising, commercialism, and access to care. Although the profession's interest and expertise in ethics has grown enormously in the last three decades, the issues facing dentistry have not really decreased, and perhaps have grown more problematic. Thus, despite the invaluable contributions of ethical progress to the structure and function of our profession, this paper argues that reflective ethics by itself appears unable to exact change. For change to occur, dentistry also needs a broad-based display of enlightened, and ethically-driven but action-oriented professionalism. This existed in the 1830s when U.S. dentistry was in its early stages of becoming thought of as a profession. Using the lessons learned from that period of our history, we need to do the same thing now-not excluding ethics, but working hand in glove with ethics. This paper suggests that, as in the 1830s, dentistry now needs the grassroots attention of its membership. Using recent publications about the importance of "connectedness" in dentistry, guidelines are presented that provide a framework for approaching the problems faced by dentistry and contributing to a more satisfying professional career. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) has become a routine intervention in contemporary American dental practice, especially in the management of children. However, routines translate to confidence which in turn may lead to overconfidence, such that possible risks and misuses are insufficiently acknowledged. This article ethically evaluates the use of nitrous oxide as a practice routine in treating children. Nitrous oxide administration is analyzed in reference to three internationally acknowledged principles of dental ethics: nonmaleficence, beneficence, and patient autonomy. In reference to the principle of nonmaleficence, the potential for adverse effects of N2O is discussed, particularly when it is administered in conjunction with other sedatives and anesthetics. The importance of abiding by clinical protocols is emphasized. Next, in reference to the principle of beneficence, the authors address the problematic application of N2O for the benefit of individuals other than the patient (e.g., dentists and parentsl. Finally, the importance of respecting patient autonomy is discussed, specifically the need to obtain explicit consent for N2O. The article supports the continued use of nitrous oxide but advises greater attention to how and why it is administered. Four recommendations are offered for an ethically sound usage. [ABSTRACT FROM AUTHOR]

For 44 years Dr. Hugo A. Owens was a distinguished practitioner and community leader in Portsmouth, Virginia. Besides his affinity to for dentistry, he was driven by two other passions: politics and civil rights. In 1970 he was one of the first African- Americans elected to the Portsmouth City Council. He was reelected for the next term and appointed Vice Mayor, a position he held for eight years. His political successes were preceded by his activities as a civil rights leader, which began in 1950 and lasted through the 1960s. In a remarkable series of negotiations and litigations, Dr. Owens was the prime mover in the desegregation of the City of Portsmouth. In all three 'careers,' Dr. Owens used dentistry as a home base for the expression of his activist philosophy of providing help for others when they were unable to do things for themselves. [ABSTRACT FROM AUTHOR]

For 44 years Dr. Hugo A. Owens was a distinguished practitioner and community leader in Portsmouth, Virginia. Besides his affinity to for dentistry, he was driven by two other passions: politics and civil rights. In 1970 he was one of the first African-Americans elected to the Portsmouth City Council. He was reelected for the next term and appointed Vice Mayor, a position he held for eight years. His political successes were preceded by his activities as a civil rights leader, which began in 1950 and lasted through the 1960s. In a remarkable series of negotiations and litigations, Dr. Owens was the prime mover in the desegregation of the City of Portsmouth. In all three 'careers, Dr. Owens used dentistry as a home base for the expression of his activist philosophy of providing help for others when they were unable to do things for themselves. [ABSTRACT FROM AUTHOR]

The article focuses on the humanities of dental education on children. It says that practitioner-patient relationship can be developed using media, literature, and other social programs including filmshowing, dramatic reading, and seminars. It also assesses the participants' view on the objective and operational aspect regarding the seminar program implemented by the faculties of University of Maryland.