Publications by authors named "Ruiter D"

Strontium isotope (Sr/Sr) analysis with reference to strontium isotope landscapes (Sr isoscapes) allows reconstructing mobility and migration in archaeology, ecology, and forensics. However, despite the vast potential of research involving Sr/Sr analysis particularly in Africa, Sr isoscapes remain unavailable for the largest parts of the continent. Here, we measure the Sr/Sr ratios in 778 environmental samples from 24 African countries and combine this data with published data to model a bioavailable Sr isoscape for sub-Saharan Africa using random forest regression.

View Article and Find Full Text PDF

More than 150 hominin teeth, dated to ∼330-241 thousand years ago, were recovered during the 2013-2015 excavations of the Dinaledi Chamber of the Rising Star cave system, South Africa. These fossils comprise the first large single-site sample of hominin teeth from the Middle Pleistocene of Africa. Though scattered remains attributable to Homo sapiens, or their possible lineal ancestors, are known from older and younger sites across the continent, the distinctive morphological feature set of the Dinaledi teeth supports the recognition of a novel hominin species, Homo naledi.

View Article and Find Full Text PDF

Objectives: There is a bidirectional relationship between cardiovascular and renal disease. The drug-class of SGLT2 inhibitors improves outcomes at both ends of this so called cardiorenal axis. We assessed the effects of SGLT2 inhibition and sulfonylurea treatment on systemic hemodynamic function and investigated whether SGLT2 inhibitor-induced changes in systemic hemodynamics correlate with changes in renal hemodynamics.

View Article and Find Full Text PDF
Article Synopsis
  • The study aimed to investigate if microcirculatory remodeling occurs downstream of coronary stenoses in humans, despite previous experimental findings suggesting it happens.
  • Researchers analyzed heart tissue from 55 deceased patients, focusing on various microcirculatory parameters, including arteriolar and capillary density.
  • Results showed no significant differences in microcirculatory structure between arteries with and without stenosis, concluding that noncritical stenoses do not lead to structural changes in the coronary microcirculation.
View Article and Find Full Text PDF

Objective: Impaired insulin sensitivity is associated with hyperfiltration (i.e., elevated glomerular filtration rate [GFR]) in adolescents with type 2 diabetes (T2D) and adults with prediabetes.

View Article and Find Full Text PDF

Excavations in the Lesedi Chamber (U.W. 102) of the Rising Star cave system from 2013 to 2015 resulted in the recovery of 131 fossils representing at least three individuals attributed to Homo naledi.

View Article and Find Full Text PDF

, a new genus within the Limnephilidae, is proposed to include , , and . Characters for the adults and larvae are presented to separate from . A summary of the distribution and life history of the species is provided.

View Article and Find Full Text PDF

This study describes three incudes recovered from the Dinaledi Chamber in the Rising Star cave system in South Africa. All three bones were recovered during sieving of excavated sediments and likely represent three Homo naledi individuals. Morphologically and metrically, the Dinaledi ossicles resemble those of chimpanzees and Paranthropus robustus more than they do later members of the genus Homo, and fall outside of the modern human range of variation in several dimensions.

View Article and Find Full Text PDF

Based on examination of ~180,000 specimens from 695 collections of 443 localities collected from the 1930s to 2015 we report 295 species of caddisflies from Michigan. Of these, 41 are reported from the state for the first time. Another 18 species previously reported from Michigan are listed as doubtful.

View Article and Find Full Text PDF

The Rising Star cave system has produced abundant fossil hominin remains within the Dinaledi Chamber, representing a minimum of 15 individuals attributed to . Further exploration led to the discovery of hominin material, now comprising 131 hominin specimens, within a second chamber, the Lesedi Chamber. The Lesedi Chamber is far separated from the Dinaledi Chamber within the Rising Star cave system, and represents a second depositional context for hominin remains.

View Article and Find Full Text PDF

Objectives: To determine the advantages of radiological imaging of a collection of full-term teratological fetuses in order to increase their scientific and educational value. BACKGROUND : Anatomical museums around the world exhibit full-term teratological fetuses. Unfortunately, these museums are regularly considered as "morbid cabinets".

View Article and Find Full Text PDF

Australopiths exhibit a number of derived facial features that are thought to strengthen the face against high and/or repetitive loads associated with a diet that included mechanically challenging foods. Here, we use finite element analysis (FEA) to test hypotheses related to the purported strengthening role of the zygomatic root and "anterior pillar" in australopiths. We modified our previously constructed models of Sts 5 (Australopithecus africanus) and MH1 (A.

View Article and Find Full Text PDF

The species Homo naledi was recently named from specimens recovered from the Dinaledi Chamber of the Rising Star cave system in South Africa. This large skeletal sample lacks associated faunal material and currently does not have a known chronological context. In this paper, we present comprehensive descriptions and metric comparisons of the recovered cranial and mandibular material.

View Article and Find Full Text PDF

The discovery of Homo naledi has expanded the range of phenotypic variation in Homo, leading to new questions surrounding the mosaic nature of morphological evolution. Though currently undated, its unique morphological pattern and possible phylogenetic relationships to other hominin taxa suggest a complex evolutionary scenario. Here, we perform geometric morphometric analyses on H.

View Article and Find Full Text PDF

Objectives: Australopithecus sediba is characterized further by providing formerly unpublished and refined mesiodistal and buccolingual crown measurements in the MH1 and MH2 specimens. After size correction, these data were compared with those in other fossil and recent samples to facilitate additional insight into diachronic hominin affinities.

Materials And Methods: Six comparative samples consist of fossil species: A.

View Article and Find Full Text PDF

Fossils attributed to Australopithecus sediba are described as having phylogenetic affinities with early Homo to the exclusion of other South African australopiths. With respect to functional anatomy of mastication, one implication of this hypothesis is that A. sediba mandibles should exhibit absolutely and relatively reduced stiffness and strength in comparison to Australopithecus africanus and Paranthropus robustus jaws.

View Article and Find Full Text PDF

Background: Misconceptions are ideas that are inconsistent with current scientific views. They are difficult to detect and refractory to change. Misconceptions can negatively influence how new concepts in science are learned, but are rarely measured in biomedical courses.

View Article and Find Full Text PDF

Homo naledi is a recently discovered species of fossil hominin from South Africa. A considerable amount is already known about H. naledi but some important questions remain unanswered.

View Article and Find Full Text PDF

Australopithecus sediba has been hypothesized to be a close relative of the genus Homo. Here we show that MH1, the type specimen of A. sediba, was not optimized to produce high molar bite force and appears to have been limited in its ability to consume foods that were mechanically challenging to eat.

View Article and Find Full Text PDF

Studies of sensory capacities in past life forms have offered new insights into their adaptations and lifeways. Audition is particularly amenable to study in fossils because it is strongly related to physical properties that can be approached through their skeletal structures. We have studied the anatomy of the outer and middle ear in the early hominin taxa Australopithecus africanus and Paranthropus robustus and estimated their auditory capacities.

View Article and Find Full Text PDF

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H.

View Article and Find Full Text PDF

We describe the physical context of the Dinaledi Chamber within the Rising Star cave, South Africa, which contains the fossils of Homo naledi. Approximately 1550 specimens of hominin remains have been recovered from at least 15 individuals, representing a small portion of the total fossil content. Macro-vertebrate fossils are exclusively H.

View Article and Find Full Text PDF

Villmoare et al. (Reports, 20 March 2015, p. 1352) report on a hominin mandible from the Ledi-Geraru research area, Ethiopia, which they claim to be the earliest known representative of the genus Homo.

View Article and Find Full Text PDF

Background: Underutilization of dialogue among students during small-group work is a threat to active meaningful learning. To encourage small-group learning, we challenged students to generate written questions during a small-group work session. As gender differences have been shown to affect learning, these were also inventoried.

View Article and Find Full Text PDF

Gyrification of the human cerebral cortex allows for the surface expansion that accommodates many more cortical neurons in comparison to other mammals. For neuroimaging, however, it forms a feature that complicates analysis. For example, it has long been established that cortical layers do not occupy the same depth in gyri and sulci.

View Article and Find Full Text PDF