An uncritical reliance on the phylogenetic species concept has led paleoanthropologists to become increasingly typological in their delimitation of new species in the hominin fossil record. As a practical matter, this approach identifies species as diagnosably distinct groups of fossils that share a unique suite of morphological characters but, ontologically, a species is a metapopulation lineage segment that extends from initial divergence to eventual extinction or subsequent speciation. Working from first principles of species concept theory, it is clear that a reliance on morphological diagnosabilty will systematically overestimate species diversity in the fossil record; because morphology can evolve within a lineage segment, it follows that early and late populations of the same species can be diagnosably distinct from each other.
View Article and Find Full Text PDFBackground: The Drimolen Palaeocave site is situated within the UNESCO Fossil Hominid Sites of South Africa World Heritage Area and has yielded numerous hominin fossils since its discovery in 1992. Most of these fossils are represented by isolated dental elements, which have been attributed to either of two distinct hominin genera, and
Aim: This paper provides morphological descriptions for a further 19 specimens that have been recovered from the ∼2.04-1.
Paranthropus robustus is a small-brained extinct hominin from South Africa characterized by derived, robust craniodental morphology. The most complete known skull of this species is DNH 7 from Drimolen Main Quarry, which differs from P. robustus specimens recovered elsewhere in ways attributed to sexual dimorphism.
View Article and Find Full Text PDFUnderstanding the extinction of and origins of and in South Africa has been hampered by the perceived complex geological context of hominin fossils, poor chronological resolution, and a lack of well-preserved early specimens. We describe, date, and contextualize the discovery of two hominin crania from Drimolen Main Quarry in South Africa. At ~2.
View Article and Find Full Text PDFHaasgat is a primate-rich fossil locality in the northeastern part of the Fossil Hominid Sites of South Africa UNESCO World Heritage Site. Here we report the first hominin identified from Haasgat, a partial maxillary molar (HGT 500), that was recovered from an ex situ calcified sediment block sampled from the locality. The in situ fossil bearing deposits of the Haasgat paleokarstic deposits are estimated to date to slightly older than 1.
View Article and Find Full Text PDFAm J Nucl Med Mol Imaging
August 2015
After initial therapy and total resection of glioblastoma multiforme (GBM), 80-90% of recurrences occur at the surgical margins. Insufficient sensitivity and specificity of current imaging techniques based on non-specific vascular imaging agents lead to delay in diagnosis of residual and/or recurrent disease. A tumor-specific imaging agent for GBM may improve detection of small residual disease in the post-operative period, and improve ability to distinguish tumor recurrence from its imaging mimics that can delay diagnosis.
View Article and Find Full Text PDFPurpose: Estrogen receptor (ER) targeting is key in management of receptor-positive breast cancer. Currently, there are no methods to optimize anti-ER therapy dosing. This study assesses the use of 16α-(18)F-fluoroestradiol ((18)F-FES) PET for fulvestrant dose optimization in a preclinical ER(+) breast cancer model.
View Article and Find Full Text PDFObjectives: Often peptides used in synthesis of radiopharmaceutical PET tracers are lipophilic and adhere to the walls of container closure systems (CCS) such that costly peptide and product are not fully recoverable after synthesis occurs. This investigation compares a standard United States Pharmacopeia (USP) Type I borosilicate glass CCS to a cyclic polyolefin copolymer Crystal Zenith(®) (CZ) CCS, for (68)Ga-chloride and (68)Ga-DOTATOC ([(68)Ga] Ga-DOTA-D-Phe1-Tyr3-octreotide) retention in the reaction vial after labeling.
Methods: (68)Gallium labeling of DOTATOC was conducted by adding (68)Ga-chloride, 2M HEPES (4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid) or 0.
We report an automated synthesis of [(18)F]-FMISO utilizing a prototype microfluidic radiochemistry module. The instrument allows for production of the tracer with 58%±2% (11 runs) decay corrected yield. Total time of production, including synthesis and purification averages 60 min.
View Article and Find Full Text PDFJ Pediatr Gastroenterol Nutr
October 1990
A familial syndrome of congenital short small bowel, malrotation, and functional bowel obstruction is presented and illustrated in three male siblings with one long-term survivor. Including the present three cases there have been 18 similar cases found in the literature. This disorder appears to be a sex-linked recessive inheritance.
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