Publications by authors named "Proffitt T"

The earliest evidence for complex tool use in the archaeological record dates to 3.3 Ma. While wooden tools may have been used by our earliest ancestors, the evidence is absent due to poor preservation.

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The origin of tool use is a central question in human evolutionary studies. Plio-Pleistocene core and flake technologies represent the earliest evidence of tool use in the human lineage. Some suggest this form of tool use is probably pre-dated by a phase of percussive tool use.

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The archaeological record offers insights into our evolutionary past by revealing ancient behaviour through stone and fossil remains. Percussive foraging is suggested to be particularly relevant for the emergence of tool-use in our lineage, yet early hominin percussive behaviours remain largely understudied compared to flaked technology. Stone tool-use of extant primates allows the simultaneous investigation of their artefacts and the associated behaviours.

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Background: Post-intensive care syndrome (PICS) affects 25% to 50% of adults who survive an intensive care unit (ICU) stay. Although the compounding of PICS impairments (cognitive, physical, and psychological) could intensify the syndrome, research on relationships among impairments is limited, particularly in patients with delirium.

Objectives: To examine associations among PICS impairments and examine delirium status and its relationship to PICS impairments at ICU discharge and 1 month later.

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Article Synopsis
  • Living nonhuman primates offer crucial insights into the biological and cultural evolution of hominins, especially in understanding tool use and behavioral adaptations.
  • Although the Oldowan tool culture is often viewed as a significant evolutionary leap, some argue it may simply extend tool behaviors seen in apes.
  • An agent-based model suggests that while ape tool transport helps clarify some archaeological variations, it cannot fully explain Oldowan patterns due to limitations in how far tools can be moved using short-distance transport methods.
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Archaeological evidence informs our understanding of the evolution of hominin behaviour. Such evidence is traditionally used to reconstruct hominin activities and intentions. In the Plio-Pleistocene, the presence or absence of specific tools and variation in artefact density is often used to infer foraging strategies, cognitive traits and functional activities.

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The drivers of cognitive change following first-episode psychosis remain poorly understood. Evidence regarding the role of antipsychotic medication is primarily based on naturalistic studies or clinical trials without a placebo arm, making it difficult to disentangle illness from medication effects. A secondary analysis of a randomised, triple-blind, placebo-controlled trial, where antipsychotic-naive patients with first-episode psychotic disorder were allocated to receive risperidone/paliperidone or matched placebo plus intensive psychosocial therapy for 6 months was conducted.

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Intentionally produced sharp-edged stone flakes and flaked pieces are our primary evidence for the emergence of technology in our lineage. This evidence is used to decipher the earliest hominin behavior, cognition, and subsistence strategies. Here, we report on the largest lithic assemblage associated with a primate foraging behavior undertaken by long-tailed macaques ().

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The earliest hominin archaeological sites preserve a record of stone tools used for cutting and pounding. Traditionally, sharp-edged flakes were seen as the primary means by which our earliest ancestors interacted with the world. The importance of pounding tools is increasingly apparent.

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When and how human ancestors first used tools remains unknown, despite intense research into the origins of technology. It has been hypothesized that the evolutionary roots of stone flake technology has its origin in percussive behavior. Before intentional stone flaking, hominins potentially engaged in various percussive behaviors resulting in accidental flake detachments.

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Northern Europe experienced cycles of hominin habitation and absence during the Middle Pleistocene. Fluvial gravel terrace sites in the east of Britain and north of France provide a majority of the data contributing to this understanding, mostly through the presence or absence of stone-tool artefacts. To date, however, relatively few sites have been radiometrically dated, and many have not been excavated in modern times, leading to an over-reliance on selectively sampled and poorly dated lithic assemblages.

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The ability to modify the environment through the transport of tools has been instrumental in shaping the evolutionary success of humans. Understanding the cause-and-effect relationships between hominin behavior and the environment ultimately requires understanding of how the archaeological record forms. Observations of living primates can shed light on these interactions by investigating how tool-use behaviors produce a material record within specific environmental contexts.

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The Early Stone Age record preserves a rich behavioural signature of hominin stone tool making and use. The role of percussive technology in the daily subsistence strategies of our earliest ancestors has seen renewed focus recently. Studies of modern primate tool use highlight the diverse range of behaviours potentially associated with percussive technology.

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Objective: Screening tools for delirium are being used more consistently in pediatric critical care. However, screening is not universal, and delirium may be underdiagnosed, misdiagnosed, or undocumented in hospitalized patients. We evaluated the identification and documentation of delirium in pediatric oncology and bone marrow transplant patients.

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For more than 1.8 million years hominins at Olduvai Gorge were faced with a choice: whether to use lavas, quartzite or chert to produce stone tools. All are available locally and all are suitable for stone tool production.

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Stone tools in the prehistoric record are the most abundant source of evidence for understanding early hominin technological and cultural variation. The field of primate archaeology is well placed to improve our scientific knowledge by using the tool behaviours of living primates as models to test hypotheses related to the adoption of tools by early stone-age hominins. Previously we have shown that diversity in stone tool behaviour between neighbouring groups of long-tailed macaques () could be explained by ecological and environmental circumstances (Luncz et al.

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The human archaeological record changes over time. Finding such change in other animals requires similar evidence, namely, a long-term sequence of material culture. Here, we apply archaeological excavation, dating and analytical techniques to a wild capuchin monkey (Sapajus libidinosus) site in Serra da Capivara National Park, Brazil.

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Background: The number of adults who survive a critical illness involving admission to an intensive care unit is increasing. These survivors have an increased risk of developing impairments in cognition, physical function and psychological health.

Objective: This integrative literature review examined the literature for studies exploring the relationships among two or more of the variables of interest, i.

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Background: Elevated homocysteine is observed in schizophrenia and associated with illness severity. The aim of this study was to determine whether vitamins B, B, and folic acid lower homocysteine and improve symptomatology and neurocognition in first-episode psychosis. Whether baseline homocysteine, genetic variation, sex, and diagnosis interact with B-vitamin treatment on outcomes was also examined.

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Background: High unemployment is a hallmark of psychotic illness. Individual placement and support (IPS) may be effective at assisting the vocational recoveries of young people with first-episode psychosis (FEP).AimsTo examine the effectiveness of IPS at assisting young people with FEP to gain employment (Australian and Clinical Trials Registry ACTRN12608000094370).

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Archaeological recovery of chimpanzee Panda oleosa nut cracking tools at the Panda 100 (P100) and Noulo sites in the Taï Forest, Côte d'Ivoire, showed that this behavior is over 4000 years old, making it the oldest known evidence of non-human tool use. In 2002, the first report on the lithic material from P100 was directly compared to early hominin stone tools, highlighting their similarities and proposing the name 'Pandan' for the chimpanzee material. Here we present an expanded and comprehensive technological, microscopic, and refit analysis of the late twentieth century lithic assemblage from P100.

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One rare complication of appendectomy is a retained appendicolith, which can become a focal point for infection presenting hours to years after surgery. We present a case in which a 50-year-old male presented to the emergency department with a small bowel obstruction one week post appendectomy. A diagnostic laparoscopy was performed, and a necrotic appendiceal specimen containing a staple line across the base as well as an appendicolith was removed.

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Debates regarding the validity of the Developed Oldowan as separate cultural facies within the Oldowan techno-complex have primarily concentrated on the Developed Oldowan B/Acheulean transition, with little attention paid to the validity of the Developed Oldowan A (DOA) as a valid technological differentiation. This study presents a diachronic technological analysis and comparison of Oldowan and DOA lithic assemblages from Olduvai Gorge, Tanzania, dated between 1.84 and 1.

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The discovery of oil palm () nut-cracking by wild long-tailed macaques () is significant for the study of non-human primate and hominin percussive behaviour. Up until now, only West African chimpanzees () and modern human populations were known to use stone hammers to crack open this particular hard-shelled palm nut. The addition of non-habituated, wild macaques increases our comparative dataset of primate lithic percussive behaviour focused on this one plant species.

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