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1.
PLoS One ; 16(9): e0254240, 2021.
Article in English | MEDLINE | ID: mdl-34529697

ABSTRACT

"Barbarism" is perhaps best understood as a recurring syndrome among peripheral societies in response to the threats and opportunities presented by more developed neighbors. This article develops a mathematical model of barbarigenesis-the formation of "barbarian" societies adjacent to more complex societies-and its consequences, and applies the model to the case of Europe in the first millennium CE. A starting point is a game (developed by Hirshleifer) in which two players allocate their resources either to producing wealth or to fighting over wealth. The paradoxical result is that a richer and potentially more powerful player may lose out to a poorer player, because the opportunity cost of fighting is greater for the former. In a more elaborate spatial model with many players, the outcome is a wealth-power mismatch: central regions have comparatively more wealth than power, peripheral regions have comparatively more power than wealth. In a model of historical dynamics, a wealth-power mismatch generates a long-lasting decline in social complexity, sweeping from more to less developed regions, until wealth and power come to be more closely aligned. This article reviews how well this model fits the historical record of late Antiquity and the early Middle Ages in Europe both quantitatively and qualitatively. The article also considers some of the history left out of the model, and why the model doesn't apply to the modern world.


Subject(s)
Civilization/history , Disasters/prevention & control , Population Dynamics , Social Change , Societies/organization & administration , Archaeology , Disasters/economics , History, Ancient , Humans , Models, Theoretical , Rome
2.
Vet Clin Pathol ; 46(2): 344-353, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28346682

ABSTRACT

BACKGROUND: Previous reports reveal variation in the cellular composition of equine bronchoalveolar lavage fluid (BALF). OBJECTIVES: The purpose of this study was to compare the profiles of BALF from horses to assess age-related differences. Serial BALF samples were collected from the same individuals over a one-year period to identify changes in individual animals as they aged. METHODS: Collection of BALF was performed on horses aged one week and one, 2, 6, and 12 months. Total nucleated cell count (TNCC), protein concentration, and cytology were assessed. Longitudinal analysis was performed and compared to healthy adults. RESULTS: Foals at one week and 6 months of age had significantly higher TNCC than adults (medians: 320/µL, 285/µL, and 90/µL, respectively); no differences in total protein were found. Foals at one month had the highest proportion of macrophages (median: 87.3%), differing significantly from both yearlings and adults (medians: 45.5% and 48.7%, respectively). Foals aged one week and one month had significantly lower proportions of lymphocytes than yearlings and adults (medians: 3.2% and 4.7% vs 43.2% and 45.8%, respectively). Eosinophil percentage was lowest in foals aged one week, one month, and 2 months (median: 0.0%) and highest in foals aged 6 months (median: 2.2%). Mast cell percentages were highest in yearlings and adults (medians: 2.2% and 3.3%, respectively) and neutrophil percentage was highest in foals aged one week (13.7%). CONCLUSIONS: Cytologic profiles of BALF from foals and adult horses differed considerably. Significant changes in TNCC and percentages of lymphocytes, macrophages, and eosinophils occurred with age.


Subject(s)
Bronchoalveolar Lavage Fluid/cytology , Horses/anatomy & histology , Age Factors , Aging/pathology , Aging/physiology , Animals , Female , Horses/physiology , Male
3.
PLoS One ; 11(6): e0155596, 2016.
Article in English | MEDLINE | ID: mdl-27305045

ABSTRACT

Kin selection, which can lead organisms to behave altruistically to their genetic relatives, works differently when-as is often the case in human societies-altruism can be boosted by social pressure. Here I present a model of social norms enforced by indirect reciprocity. In the model there are many alternative stable allocations of rewards ("distributional norms"); a stable norm is stable in the sense that each player is best off following the norm if other players do the same. Stable norms vary widely in how equally they reward players with unequal abilities. In a population of mixed groups (some group members follow one norm, some follow another, and some compromise) with modest within-group coefficients of relatedness, selection within groups favors those who compromise, and selection between groups favors generous generalized reciprocity rather than balanced reciprocity. Thus evolved social norms can amplify kin altruism, giving rise to a uniquely human mode of kin-based sociality distinct from spontaneous altruism among close kin, or cooperation among non-kin.


Subject(s)
Altruism , Cooperative Behavior , Interpersonal Relations , Social Behavior , Algorithms , Family , Humans , Models, Theoretical
4.
J Vasc Surg Venous Lymphat Disord ; 3(1): 86-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-26993686

ABSTRACT

Inferior vena cava filter (IVCF) placement is associated with increased risk of deep venous thrombosis. This may result from filter obstruction by trapped emboli or in situ thrombosis of the IVCF, followed by caval thrombus propagation, and may be associated with significant morbidity. Here, we describe a technique and early results of endovascular recanalization of IVCF chronic total occlusions in five patients with complete chronic total occlusions of a previously implanted IVCF, the inferior vena cava, and the bilateral iliofemoral venous systems. We describe our technique of filter displacement and recanalization with balloon-mounted and self-expanding stents. All patients noted sustained clinical improvement and duplex ultrasound-confirmed patency throughout follow-up.


Subject(s)
Vena Cava Filters , Vena Cava, Inferior , Venous Thrombosis/therapy , Endovascular Procedures , Humans , Treatment Outcome , Ultrasonography, Doppler, Duplex
5.
Br J Sports Med ; 46(7): 538-42, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22510645

ABSTRACT

BACKGROUND: Shoulder injuries in rugby players are common, but the mechanisms of injury are less well understood. This study aims to elucidate common mechanisms of injury and identify the patterns of injury they produce. MATERIALS AND METHODS: Twenty-four elite rugby players, referred to the senior author for diagnosis and management of shoulder injuries, were selected. Videos of the injuries were independently reviewed by rugby-medical experts to describe the mechanisms of injury. The mechanisms reported were collated and analysed to determine the level of agreement between reviewers and conclude an overall description of injury mechanisms. RESULTS: The authors identified three mechanisms of shoulder injury from the video analysis. These are the 'Try-Scorer', characterised by hyperflexion of the outstretched arm such as when scoring a try; the 'Tackler', extension of the abducted arm behind the player while tackling; and the 'Direct Impact', a direct blow to the arm or shoulder when held by the side in neutral or slight adduction. The Try Scorer and Tackler mechanisms both involve a levering force on the glenohumeral joint (GHJ). These mechanisms predominantly cause GHJ dislocation, with Bankart, reverse Bankart and superior labrum anterior-posterior tears. The Try-Scorer Mechanism also caused the majority (83%) of rotator cuff tears. The Direct Hit mechanism resulted in GHJ dislocation and labral injury in 37.5% of players and was most likely to cause acromioclavicular joint dislocation and scapula fractures, injuries that were not seen with the other mechanisms. CONCLUSION: Greater understanding of the mechanisms involved in rugby shoulder injury is useful in understanding the pathological injuries, guiding treatment and rehabilitation and aiding the development of injury-prevention methods.


Subject(s)
Football/injuries , Shoulder Injuries , Adult , Athletic Injuries/etiology , Humans , Male , Shoulder Dislocation/etiology , Video Recording , Young Adult
6.
Vaccine ; 29(33): 5443-52, 2011 Jul 26.
Article in English | MEDLINE | ID: mdl-21641955

ABSTRACT

Vaxfectin(®) is a lipid-based adjuvant initially developed for use with plasmid DNA (pDNA) vaccines. Here we present detailed nonclinical assessments performed prior to Vaxfectin(®)'s first-in-man use, as an adjuvant in the H5N1 influenza vaccine VCL-IPT1. Following IM delivery to rabbits, VCL-IPT1 pDNA localized primarily to injection sites, where levels steadily declined over the 2 months examined. Risk of pDNA integration into genomic DNA was negligible. Toxicology studies in rabbits revealed mild inflammatory/immune responses at injection sites characteristic of IM vaccine delivery; Vaxfectin(®) directly contributed to these responses. These data support clinical development of H5N1 pDNA vaccines, and also present an encouraging profile for further development of Vaxfectin(®) as an adjuvant for vaccines in general.


Subject(s)
Adjuvants, Immunologic/pharmacokinetics , Influenza A Virus, H5N1 Subtype/genetics , Influenza Vaccines/pharmacokinetics , Phosphatidylethanolamines/pharmacokinetics , Vaccines, DNA/pharmacokinetics , Adjuvants, Immunologic/administration & dosage , Adjuvants, Immunologic/adverse effects , Animals , Influenza Vaccines/administration & dosage , Influenza Vaccines/adverse effects , Influenza Vaccines/genetics , Injections, Intramuscular , Male , Phosphatidylethanolamines/administration & dosage , Phosphatidylethanolamines/adverse effects , Rabbits , Vaccines, DNA/administration & dosage , Vaccines, DNA/adverse effects , Vaccines, DNA/genetics
7.
Hum Nat ; 22(1-2): 177-200, 2011 Jul.
Article in English | MEDLINE | ID: mdl-22388807

ABSTRACT

This article integrates (1) research in the historical dynamics of state societies relating group solidarity and group expansion to cultural frontiers, (2) comparative research in anthropology relating matrilocality to a particular variety of internal politics and a particular form of warfare, and (3) interdisciplinary reconstructions of large-scale "demic expansions" and associated kinship systems in prehistory. The argument is that "metaethnic frontiers," where very different cultures clash, are centers for the formation of larger, more enduring, and more militarily effective groups. In small-scale non-state societies, the major path toward the formation of such groups is the establishment of cross-cutting ties among men. This often involves the adoption of matrilocal norms. The current distribution of matrilocality and matrilineality around the world may be partly a residue of major demic expansions in prehistory involving matrilocal tribes. This hypothesis is evaluated with a range of evidence, including information regarding the spread of two language families, Bantu and Austronesian.


Subject(s)
Family Characteristics/ethnology , Family Relations/ethnology , Marriage/ethnology , Residence Characteristics/statistics & numerical data , Africa , Brazil , Cooperative Behavior , Culture , Emigration and Immigration , Food , Humans , Indians, South American/ethnology , Language , Sex Factors , Warfare
8.
Behav Brain Sci ; 33(5): 367-404; discussion 404-16, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21205333

ABSTRACT

Research in anthropology has shown that kin terminologies have a complex combinatorial structure and vary systematically across cultures. This article argues that universals and variation in kin terminology result from the interaction of (1) an innate conceptual structure of kinship, homologous with conceptual structure in other domains, and (2) principles of optimal, "grammatical" communication active in language in general. Kin terms from two languages, English and Seneca, show how terminologies that look very different on the surface may result from variation in the rankings of a universal set of constraints. Constraints on kin terms form a system: some are concerned with absolute features of kin (sex), others with the position (distance and direction) of kin in "kinship space", others with groups and group boundaries (matrilines, patrilines, generations, etc.). Also, kin terms sometimes extend indefinitely via recursion, and recursion in kin terminology has parallels with recursion in other areas of language. Thus the study of kinship sheds light on two areas of cognition, and their phylogeny. The conceptual structure of kinship seems to borrow its organization from the conceptual structure of space, while being specialized for representing genealogy. And the grammar of kinship looks like the product of an evolved grammar faculty, opportunistically active across traditional domains of semantics, syntax, and phonology. Grammar is best understood as an offshoot of a uniquely human capacity for playing coordination games.


Subject(s)
Cognition , Family/psychology , Language , Terminology as Topic , Concept Formation , Culture , Humans , Indians, North American/psychology , Psychological Theory , Semantics , White People/psychology
9.
Clin Nutr ; 29(1): 18-23, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19419806

ABSTRACT

BACKGROUND & AIMS: Older individuals are more likely to experience extended hospitalization and become protein malnourished during hospitalization. The concomitant compulsory inactivity results in functional decline. Increasing protein intake in hospitalized patients improves nitrogen balance, but effects on function are unknown. In the present study, we examined the effects of increasing protein intake by essential amino acid (EAA) supplementation in older individuals subjected to 10 d bed rest on LBM and muscle function. METHODS: Subjects were given a placebo (n=12, 68+/-5 (SD) yrs, 83+/-19 kg) or 15 g of EAA (n=10, 71+/-6, 72+/-8 kg) 3 times per day throughout 10d of bed rest. LBM, muscle protein synthesis, and muscle function were determined before and after bed rest. Due to an imbalance in randomized gender distribution between groups, gender and beginning functional and LBM measures were utilized for analyses by repeated measures analysis of covariance (RMANCOVA). RESULTS: Analyses revealed the potential for the preservation of functional outcomes with EAA supplementation. CONCLUSIONS: Increasing protein intake above the RDA may preserve muscle function in the elderly during compulsory inactivity. EAA supplementation is potentially an efficient method of increasing protein intake without affecting satiety.


Subject(s)
Aged/physiology , Amino Acids, Essential/therapeutic use , Bed Rest , Dietary Supplements , Muscle, Skeletal/drug effects , Muscle, Skeletal/physiology , Nitrogen/metabolism , Absorptiometry, Photon , Aging , Amino Acids, Essential/administration & dosage , Analysis of Variance , Body Composition/drug effects , Female , Hospitalization , Humans , Male , Muscle Proteins/biosynthesis , Muscle Proteins/drug effects , Protein-Energy Malnutrition/prevention & control
10.
Med Image Comput Comput Assist Interv ; 11(Pt 1): 967-74, 2008.
Article in English | MEDLINE | ID: mdl-18979839

ABSTRACT

Minimally invasive techniques for electrophysiological cardiac data mapping and catheter ablation therapy have been driven through advancements in computer-aided technologies, including magnetic tracking systems, and virtual and augmented-reality environments. The objective of this work is to extend current cardiac mapping techniques to collect and display data in the temporal domain, while mapping on patient-specific cardiac models. This paper details novel approaches to collecting spatially tracked cardiac electrograms, registering the data with a patient-specific cardiac model, and interpreting the data directly on the model surface, with the goal of giving a more comprehensive cardiac mapping system in comparison to current systems. To validate the system, laboratory studies were conducted to assess the accuracy of navigating to both physical and virtual landmarks. Subsequent to the laboratory studies, an in-vivo porcine experiment was conducted to assess the systems overall ability to collect spatial tracked electrophysiological data, and map directly onto a cardiac model. The results from these experiments show the new dynamic cardiac mapping system was able to maintain high accuracy of locating physical and virtual landmarks, while creating a dynamic cardiac map displayed on a dynamic cardiac surface model.


Subject(s)
Algorithms , Body Surface Potential Mapping/methods , Heart Conduction System/anatomy & histology , Heart Conduction System/physiology , Image Interpretation, Computer-Assisted/methods , Information Storage and Retrieval/methods , Animals , Computer Simulation , Humans , Image Enhancement/methods , Models, Cardiovascular , Reproducibility of Results , Sensitivity and Specificity , Swine
11.
Vet Res Commun ; 32(8): 647-57, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18566907

ABSTRACT

This report describes the development of small DNA microarrays of fully defined genes suitable for projects requiring detailed analysis of gene expression in sheep and/or cattle. Two arrays have been developed; the first is a small reference microarray (RIGRA) that has been used to validate experimental design and methodology; the second, a larger array (RIGUA) containing probes for 516 ruminant immuno-inflammatory genes, each represented by non-overlapping 75mer oligonucleotides. Experiments used to validate this microarray were: (1) a comparison of gene expression profiles from sheep broncho-alveolar macrophages before and after in vitro activation with lipopolysaccharide (LPS), using the RIGRA; (2) the differential gene expression between five in vitro unstimulated sheep keratinocyte cultures; (3) LPS/interferon gamma stimulated and unstimulated blood monocytes purified from Holstein-Friesians (Bos taurus) and Sahiwals (Bos indicus) cattle using the RIGUA. Real-time, quantitative RT-PCR was used to validate the gene expression profiles obtained with the RIGUA microarrays. The potential for using such an immunological tool in understanding the relative gene expression corresponding to immune-inflammatory responses of sheep and cattle is discussed.


Subject(s)
Cattle/genetics , Cattle/immunology , Gene Expression Profiling/veterinary , Oligonucleotide Array Sequence Analysis/veterinary , Sheep/genetics , Sheep/immunology , Animals , Cells, Cultured , Gene Expression Profiling/methods , Inflammation/genetics , Inflammation/immunology , Inflammation/veterinary , Keratinocytes/drug effects , Keratinocytes/immunology , Keratinocytes/physiology , Lipopolysaccharides/pharmacology , Macrophage Activation/drug effects , Macrophage Activation/genetics , Macrophages, Alveolar/drug effects , Macrophages, Alveolar/immunology , Macrophages, Alveolar/physiology , Oligonucleotide Array Sequence Analysis/methods , Reverse Transcriptase Polymerase Chain Reaction/veterinary
12.
Mol Biotechnol ; 40(1): 47-57, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18365771

ABSTRACT

A TaqMan-based reverse transcription polymerase chain reaction (RT-PCR) assay has been developed as an in vitro potency assay to measure the most immediate biological activity of plasmid DNA (pDNA)-based products. The assay measures transgene-specific messenger RNA (mRNA) from cultured cells transfected with VCL-CB01, a bivalent pDNA-based human cytomegalovirus (CMV) vaccine. The forward and reverse primers have been designed to make the RT-PCR reaction selective for plasmid-derived mRNA and to allow discrimination of expression levels of individual plasmids in a multivalent pDNA vaccine. The relative potency of a vaccine lot is assessed by transfecting reference and test samples into cultured cells in parallel and analyzing total RNA from the cells by RT-PCR. Statistical analysis of dose response data from reference material supports a parallel-line model for calculating relative potency. Preliminary data demonstrate the ability of this assay to distinguish product potencies at 50, 75, 150, and 200% of the reference material. In addition, forced degradation of pDNA demonstrates that a decrease in relative potency as measured by the RT-PCR assay in vitro correlates well with a decrease in CMV DNA vaccine-mediated humoral immune responses in mice injected with the same material.


Subject(s)
Plasmids , Reverse Transcriptase Polymerase Chain Reaction/methods , Vaccines/immunology , Animals , Base Sequence , Cells, Cultured , DNA Primers , Humans , In Vitro Techniques , Mice , Sensitivity and Specificity , Vaccines/genetics
13.
Stud Health Technol Inform ; 125: 322-7, 2007.
Article in English | MEDLINE | ID: mdl-17377295

ABSTRACT

Many intracardiac procedures can currently be performed on the heart only after it has been arrested, and the patient has been placed on cardio-pulmonary bypass. We have developed a new method for operating on multiple targets inside the beating heart, and describe a procedure for accessing them under virtual-reality (VR)-assisted image guidance that combines real-time ultrasound with a virtual model of tools, and the surgical environment acquired from pre-operative images. This paper presents preliminary results aimed at assessing the operator's ability to accurately position and staple an artificial valve to a "valve orifice" within a cardiac phantom when guidance is performed via ultrasound alone, and with US augmented by the VR environment.


Subject(s)
Echocardiography , Image Processing, Computer-Assisted , Surgery, Computer-Assisted , Thoracic Surgery , Heart Valve Prosthesis , Humans , Ontario
14.
Article in English | MEDLINE | ID: mdl-17354812

ABSTRACT

Registration of 3D segmented cardiac images with tracked electrophysiological data has been previously investigated for use in cardiac mapping and navigation systems. However, dynamic cardiac 4D (3D + time) registration methods do not presently exist. This paper introduces two new 4D registration methods based on the popular iterative closest point (ICP) algorithm that may be applied to dynamic 3D shapes. The first method averages the transformations of the 3D ICP on each phase of the dynamic data, while the second finds the closest point pairs for the data in each phase and performs a least squares fit between all the pairs combined. Experimental results show these methods yield more accurate transformations compared to using a traditional 3D approach (4D errors: Translation 0.4mm, Rotation 0.45 degrees vs. 3D errors: Translation 1.2mm, Rotation 1.3 degrees) while also increasing capture range and success


Subject(s)
Body Surface Potential Mapping/methods , Heart Conduction System/anatomy & histology , Heart Conduction System/physiology , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Pattern Recognition, Automated/methods , Subtraction Technique , Algorithms , Artificial Intelligence , Computer Simulation , Humans , Image Enhancement/methods , Models, Statistical , Reproducibility of Results , Sensitivity and Specificity
15.
Trends Cogn Sci ; 8(5): 211-5, 2004 May.
Article in English | MEDLINE | ID: mdl-15120679

ABSTRACT

Kinship is central to social organization in many societies; how people think about kinship should be relevant to social cognition generally. One window onto the mental representation of kinship is afforded by variation and universals in terms for kin. Kin terminologies are commonly organized around binary distinctive features, and terms for some types of kin are consistently linguistically marked. These observations can be formalized in the newly developed framework of linguistic Optimality Theory: permutations in the rank order of a small set of constraints generate basic types of kin terminology without over-generating rare or non-existent types. The result, I argue, is evidence for an innate faculty of social cognition (including several universal schemas of social relationships), apparently shaped by several kinds of genetic kin selection.


Subject(s)
Family/psychology , Language , Psycholinguistics , Social Environment , Anthropology , Classification , Cross-Cultural Comparison , Hierarchy, Social , Humans
16.
Nutrition ; 18(10): 837-41, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12361775

ABSTRACT

Space flight and the accompanying diminished muscular activity lead to a loss of body nitrogen and muscle function. These losses may affect crew capabilities and health in long-duration missions. Space flight alters protein metabolism such that the body is unable to maintain protein synthetic rates. A concomitant hypocaloric intake and altered anabolic/catabolic hormonal profiles may contribute to or exacerbate this problem. The inactivity associated with bedrest also reduces muscle and whole-body protein synthesis. For this reason, bedrest provides a good model for the investigation of potential exercise and nutritional countermeasures to restore muscle protein synthesis. We have demonstrated that minimal resistance exercise preserves muscle protein synthesis throughout bedrest. In addition, ongoing work indicates that an essential amino acid and carbohydrate supplement may ameliorate the loss of lean body mass and muscle strength associated with 28 d of bedrest. The investigation of inactivity-induced alterations in protein metabolism, during space flight or prolonged bedrest, is applicable to clinical populations and, in a more general sense, to the problems associated with the decreased activity that occur with aging.


Subject(s)
Exercise/physiology , Muscle Proteins/metabolism , Musculoskeletal Physiological Phenomena , Space Flight , Weightlessness/adverse effects , Amino Acids , Bed Rest , Humans , Models, Biological , Weightlessness Countermeasures
17.
Aust J Physiother ; 44(3): 181-185, 1998.
Article in English | MEDLINE | ID: mdl-11676732

ABSTRACT

Some communication skills adopted by 30 Australian and 27 Hong Kong final year physiotherapy students were observed by their clinical supervisor, while delivering treatment to an acute post-surgical patient in their country of origin. In each case, patient and student were racially similar and verbal communication was in their first language. The results showed that Australian students used more explanation, eye contact, verbal reinforcement, facial expression, variation of tone and response with interest, compared with Hong Kong students. Female students from both cultures used more verbal skills, such as information finding and response with interest, compared with male students; Australian female students responded with interest more frequently with female patients. When treating male patients, Hong Kong male students applied more non-therapeutic touch but less response with interest, compared with Australian male students. This study suggests that, regardless of the cultural setting, more physiotherapy student teaching resources should be channelled towards development of communication skills during undergraduate training, with particular emphasis given to verbal communication skills for male students.

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