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2.
Am J Biol Anthropol ; 183(3): e24728, 2024 Mar.
Article in English | MEDLINE | ID: mdl-36924247

ABSTRACT

OBJECTIVES: Primates employ wrist ulnar deviation during a variety of locomotor and manipulative behaviors. Extant hominoids share a derived condition in which the ulnar styloid process has limited articulation or is completely separated from the proximal carpals, which is often hypothesized to increase ulnar deviation range of motion. Acute angulation of the hamate's triquetral facet is also hypothesized to facilitate ulnar deviation mobility and mechanics. In this study, we test these longstanding ideas. METHODS: Three-dimensional (3D) carpal kinematics were examined using a cadaveric sample of Pan troglodytes, Pongo sp., and five monkey species. Ulnar styloid projection and orientation of the hamate's triquetral facet were quantified using 3D models. RESULTS: Although carpal rotation patterns in Pan and Pongo were uniquely similar in some respects, P. troglodytes exhibited overall kinematic similarity with large terrestrial cercopithecoids (Papio and Mandrillus). Pongo, Macaca, and Ateles had high wrist ulnar deviation ranges of motion, but Pongo did this via a unique mechanism. In Pongo, the triquetrum functions as a distal carpal rather than part of the proximal row. Ulnar styloid projection and wrist ulnar deviation range of motion were not correlated but ulnar deviation range of motion and the triquetrohamate facet orientation were correlated. CONCLUSIONS: Increased ulnar deviation mobility is not the function of ulnar styloid withdrawal in hominoids. Instead, this feature probably reduces stress on the ulnar side wrist or is a byproduct of adaptations that increase supination. Orientation of the hamate's triquetral facet offers some potential to reconstruct ulnar deviation mobility in extinct primates.


Subject(s)
Primates , Wrist , Humans , Animals , Wrist/anatomy & histology , Biomechanical Phenomena , Ulna/anatomy & histology , Haplorhini , Rotation , Papio , Macaca , Pongo
3.
Commun Biol ; 6(1): 1061, 2023 10 19.
Article in English | MEDLINE | ID: mdl-37857853

ABSTRACT

The evolution of the medial longitudinal arch (MLA) is one of the most impactful adaptations in the hominin foot that emerged with bipedalism. When and how it evolved in the human lineage is still unresolved. Complicating the issue, clinical definitions of flatfoot in living Homo sapiens have not reached a consensus. Here we digitally investigate the navicular morphology of H. sapiens (living, archaeological, and fossil), great apes, and fossil hominins and its correlation with the MLA. A distinctive navicular shape characterises living H. sapiens with adult acquired flexible flatfoot, while the congenital flexible flatfoot exhibits a 'normal' navicular shape. All H. sapiens groups differentiate from great apes independently from variations in the MLA, likely because of bipedalism. Most australopith, H. naledi, and H. floresiensis navicular shapes are closer to those of great apes, which is inconsistent with a human-like MLA and instead might suggest a certain degree of arboreality. Navicular shape of OH 8 and fossil H. sapiens falls within the normal living H. sapiens spectrum of variation of the MLA (including congenital flexible flatfoot and individuals with a well-developed MLA). At the same time, H. neanderthalensis seem to be characterised by a different expression of the MLA.


Subject(s)
Flatfoot , Hominidae , Adult , Animals , Humans , Hominidae/anatomy & histology , Foot/anatomy & histology , Fossils
4.
Article in English | MEDLINE | ID: mdl-36931425

ABSTRACT

Humans are unique among terrestrial mammals in our manner of walking and running, reflecting 7 to 8 Ma of musculoskeletal evolution since diverging with the genus Pan. One component of this is a shift in our skeletal muscle biology towards a predominance of myosin heavy chain (MyHC) I isoforms (i.e. slow fibers) across our pelvis and lower limbs, which distinguishes us from chimpanzees. Here, new MyHC data from 35 pelvis and hind limb muscles of a Western gorilla (Gorilla gorilla) are presented. These data are combined with a similar chimpanzee dataset to assess the MyHC I content of humans in comparison to African apes (chimpanzees and gorillas) and other terrestrial mammals. The responsiveness of human skeletal muscle to behavioral interventions is also compared to the human-African ape differential. Humans are distinct from African apes and among a small group of terrestrial mammals whose pelvis and lower limb muscle is slow fiber dominant, on average. Behavioral interventions, including immobilization, bed rest, spaceflight and exercise, can induce modest decreases and increases in human MyHC I content (i.e. -9.3% to 2.3%, n = 2033 subjects), but these shifts are much smaller than the mean human-African ape differential (i.e. 31%). Taken together, these results indicate muscle fiber content is likely an evolvable trait under selection in the hominin lineage. As such, we highlight potential targets of selection in the genome (e.g. regions that regulate MyHC content) that may play an important role in hominin skeletal muscle evolution.


Subject(s)
Hominidae , Myosin Heavy Chains , Humans , Animals , Myosin Heavy Chains/genetics , Pan troglodytes , Muscle, Skeletal , Muscle Fibers, Skeletal , Protein Isoforms , Mammals
5.
J Dent Educ ; 87(4): 583-591, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36479700

ABSTRACT

PURPOSE/OBJECTIVES: One of the most difficult local anesthetic blocks to master in dentistry is the inferior alveolar nerve block (IANB). Historically, dental students have practiced local anesthesia on one another. At the University of Colorado, these practice sessions have been limited to one required laboratory session. The predictability and confidence of student IANB success have not been high in the past. Therefore, the objective of this study was to investigate the impact of a novel IANB simulator, built on a three dimensional (3D)-printed mixed-reality haptic model, for second-year dental students to practice on prior to their laboratory session. METHODS: Thirty-nine student participants volunteered to practice with the IANB simulator. Participants were divided into two groups, Group A and Group B. Self-reported confidence and injection-specific accuracy were measured during IANB simulator practice and the laboratory session. During lab, partner numbness was assessed as a measure of IANB success. Groups A (n = 20) and B (n = 19) practiced with the simulator before and after laboratory, respectively. Injection domains were not assessed during Group B's practice with the IANB simulator. RESULTS: Self-reported confidence increased for both groups (p < 0.001). However, for anesthetic success, Group A exhibited significantly greater success (52.6%) than Group B (17.6%) (p = 0.029). CONCLUSION: Self-reported confidence in performing an IANB improved and higher anesthetic success was achieved for Group A. Further investigation is necessary to determine the long-term impact of using the IANB simulator in dental education.


Subject(s)
Anesthesia, Dental , Nerve Block , Pulpitis , Humans , Anesthesia, Local/methods , Pilot Projects , Haptic Technology , Anesthesia, Dental/methods , Nerve Block/methods , Mandibular Nerve , Anesthetics, Local , Pulpitis/surgery , Double-Blind Method , Lidocaine
6.
Am J Biol Anthropol ; 177(3): 581-602, 2022 03.
Article in English | MEDLINE | ID: mdl-35755956

ABSTRACT

Current approaches to quantify phalangeal curvature assume that the long axis of the bone's diaphysis approximates the shape of a portion of a circle (included angle method) or a parabola (second-degree polynomial method). Here we developed, tested, and employed an alternative geometric morphometrics-based approach to quantify diaphysis shape of proximal phalanges in humans, apes and monkeys with diverse locomotor behaviors. 100 landmarks of the central longitudinal axis were extracted from 3D surface models and analyzed using 2DGM methods, including Generalized Procrustes Analyses. Principal components analyses were performed and PC1 scores (>80% of variation) represented the dorsopalmar shape of the bone's central longitudinal axis and separated taxa consistently and in accord with known locomotor behavioral profiles. The most suspensory taxa, including orangutans, hylobatids and spider monkeys, had significantly lower PC1 scores reflecting the greatest amounts of phalangeal curvature. In contrast, bipedal humans and the quadrupedal cercopithecoid monkeys sampled (baboons, proboscis monkeys) exhibited significantly higher PC1 scores reflecting flatter phalanges. African ape (gorillas, chimpanzees and bonobos) phalanges fell between these two extremes and were not significantly different from each other. PC1 scores were significantly correlated with both included angle and the a coefficient of a second-degree polynomial calculated from the same landmark dataset, but had a significantly higher correlation with included angles. Our alternative approach for quantifying diaphysis shape of proximal phalanges to investigate dorsopalmar curvature is replicable and does not assume a priori either a circle or parabola model of shape, making it an attractive alternative compared with existing methodologies.


Subject(s)
Atelinae , Finger Phalanges , Hominidae , Animals , Diaphyses/diagnostic imaging , Finger Phalanges/diagnostic imaging , Gorilla gorilla
7.
Sci Rep ; 11(1): 23735, 2021 12 14.
Article in English | MEDLINE | ID: mdl-34907203

ABSTRACT

The evolution and development of human mortuary behaviors is of enormous cultural significance. Here we report a richly-decorated young infant burial (AVH-1) from Arma Veirana (Liguria, northwestern Italy) that is directly dated to 10,211-9910 cal BP (95.4% probability), placing it within the early Holocene and therefore attributable to the early Mesolithic, a cultural period from which well-documented burials are exceedingly rare. Virtual dental histology, proteomics, and aDNA indicate that the infant was a 40-50 days old female. Associated artifacts indicate significant material and emotional investment in the child's interment. The detailed biological profile of AVH-1 establishes the child as the earliest European near-neonate documented to be female. The Arma Veirana burial thus provides insight into sex/gender-based social status, funerary treatment, and the attribution of personhood to the youngest individuals among prehistoric hunter-gatherer groups and adds substantially to the scant data on mortuary practices from an important period in prehistory shortly following the end of the last Ice Age.


Subject(s)
Burial , Mortuary Practice , Social Status , Female , History, Ancient , Humans , Infant , Italy
8.
J Hum Evol ; 161: 103078, 2021 12.
Article in English | MEDLINE | ID: mdl-34749002

ABSTRACT

In 2000, a complete fourth metatarsal (Mt4) of the ∼3- to 4-Million-year-old hominin Australopithecus afarensis was recovered in Hadar, Ethiopia. This metatarsal presented a mostly human-like morphology, suggesting that a rigid lateral foot may have evolved as early as ∼3.2 Ma. The lateral foot is integral in providing stability during the push off phase of gait and is key in understanding the transition to upright, striding bipedalism. Previous comparisons of this fossil were limited to Pan troglodytes, Gorilla gorilla, and modern humans. This study builds on previous studies by contextualizing the Mt4 morphology of A. afarensis (A.L. 333-160) within a diverse comparative sample of nonhuman hominoids (n = 144) and cercopithecids (n = 138) and incorporates other early hominins (n = 3) and fossil hominoids that precede the Pan-Homo split (n = 4) to better assess the polarity of changes in lateral foot morphology surrounding this divergence. We investigate seven morphological features argued to be functionally linked to human-like bipedalism. Our results show that some human-like characters used to assess midfoot and lateral foot stiffness in the hominin fossil record are present in our Miocene ape sample as well as in living cercopithecids. Furthermore, modern nonhuman hominoids can be generally distinguished from other species in most metrics. These results suggest that the possession of a rigid foot in hominins could represent a conserved trait, whereas the specialized pedal grasping mechanics of extant apes may be more derived, in which case some traits often used to infer bipedal locomotion in early hominins may, instead, reflect a lower reliance on pedal grasping. Another possibility is that early hominins reverted from modern ape Mt4 morphology into a more plesiomorphic condition when terrestrial bipedality became a dominant behavior. More fossils dating around the Pan-Homo divergence time are necessary to test these competing hypotheses.


Subject(s)
Hominidae , Metatarsal Bones , Animals , Biological Evolution , Foot/anatomy & histology , Fossils , Metatarsal Bones/anatomy & histology
9.
J Hum Evol ; 158: 103048, 2021 09.
Article in English | MEDLINE | ID: mdl-34340120

ABSTRACT

Homo naledi fossils from the Rising Star cave system provide important insights into the diversity of hand morphology within the genus Homo. Notably, the pollical (thumb) metacarpal (Mc1) displays an unusual suite of characteristics including a median longitudinal crest, a narrow proximal base, and broad flaring intrinsic muscle flanges. The present study evaluates the affinities of H. naledi Mc1 morphology via 3D geometric morphometric analysis of shaft shape using a broader comparative sample (n = 337) of fossil hominins, recent humans, apes, and cercopithecoid monkeys than in prior work. Results confirm that the H. naledi Mc1 is distinctive from most other hominins in being narrow at the proximal end but surmounted by flaring muscle flanges distally. Only StW 418 (Australopithecus cf. africanus) is similar in these aspects of shape. The gracile proximal shaft is most similar to cercopithecoids, Pan, Pongo, Australopithecus afarensis, and Australopithecus sediba, suggesting that H. naledi retains the condition primitive for the genus Homo. In contrast, Neandertal Mc1s are characterized by wide proximal bases and shafts, pinched midshafts, and broad distal flanges, while those of recent humans generally have straight shafts, less robust muscle flanges, and wide proximal shafts/bases. Although uncertainties remain regarding character polarity, the morphology of the H. naledi thumb might be interpreted as a retained intermediate state in a transformation series between the overall gracility of the shaft and the robust shafts of later hominins. Such a model suggests that the addition of broad medial and lateral muscle flanges to a primitively slender shaft was the first modification in transforming the Mc1 into the overall more robust structure exhibited by other Homo taxa including Neandertals and recent Homo sapiens in whose shared lineage the bases and proximal shafts became expanded, possibly as an adaptation to the repeated recruitment of powerful intrinsic pollical muscles.


Subject(s)
Fossils , Hominidae/anatomy & histology , Metacarpal Bones/anatomy & histology , Animals , Biological Evolution , Caves , Haplorhini/anatomy & histology , Humans , Neanderthals/anatomy & histology
10.
J Eur Acad Dermatol Venereol ; 35(3): 762-768, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33275818

ABSTRACT

BACKGROUND: Photoageing describes complex cutaneous changes which occur following chronic exposure to solar ultraviolet radiation (UVR). Amongst White Northern Europeans, facial photoageing appears as distinct clinical phenotypes: 'hypertrophic' photoageing (HP) and 'atrophic' photoageing (AP). Deep, coarse wrinkles predominate in individuals with HP, whereas those with AP have relatively smooth, unwrinkled skin with pronounced telangiectasia. AP individuals have an increased propensity for developing keratinocyte cancers. OBJECTIVES: To investigate whether histological differences underlie these distinct phenotypes of facial photoageing. METHODS: Facial skin biopsies were obtained from participants with AP (10 M, 10 F; mean age: 78.7 years) or HP (10 M, 10 F; mean age: 74.5 years) and were assessed histologically and by immunohistochemistry. RESULTS: Demographic characterization revealed 95% of AP subjects, as compared to 35% with HP, were Fitzpatrick skin type I/II; of these, 50% had a history of one or more keratinocyte cancers. There was no history of keratinocyte cancers in the HP cohort. Analysis of UVR-induced mitochondrial DNA damage confirmed that all volunteers had received similar lifetime cumulative doses of sun exposure. Histologically, male AP had a significantly thicker epidermis than did AP females or those of either sex with HP. HP facial skin exhibited severe solar elastosis, whereas in AP facial skin, solar elastosis was apparent only in females. Loss of papillary dermal fibrillin-rich microfibrils occurred in all HP and AP female subjects, but not in AP males. Furthermore, male AP had a significant reduction in collagen VII at the dermal-epidermal junction than did AP females or those of either sex with HP. CONCLUSIONS: This study provides further evidence that AP and HP represent distinct clinical and histological entities. Knowledge of these two phenotypes is clinically relevant due to the increased prevalence of keratinocyte cancers in those - particularly males - with the AP phenotype.


Subject(s)
Skin Aging , Ultraviolet Rays , Aged , Epidermis , Face , Female , Humans , Male , Skin , Ultraviolet Rays/adverse effects
11.
Br J Dermatol ; 184(5): 923-934, 2021 05.
Article in English | MEDLINE | ID: mdl-32767748

ABSTRACT

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is a common cancer that invades the dermis through the basement membrane. The role of the basement membrane in poorly differentiated cSCC is not well understood. OBJECTIVES: To study the effect that loss of the laminin subunit alpha-3 (α3) chain from the tumour microenvironment has on tumour invasion and inflammatory cell recruitment. METHODS: We examined the role of the basement membrane proteins laminin subunits α3, ß3 and γ2 in SCC invasion and inflammatory cell recruitment using immunohistochemistry, short hairpin RNA knockdown, RNA-Seq, mouse xenograft models and patient tumour samples. RESULTS: Analysis of SCC tumours and cell lines using antibodies specific to laminin chains α3, ß3 and γ2 identified a link between poorly differentiated SCC and reduced expression of laminin α3 but not the other laminin subunits investigated. Knockdown of laminin α3 increased tumour invasion both in vitro and in vivo. Western blot and immunohistochemical staining identified increased phosphorylated myosin light chain with loss of laminin α3. Inhibition of ROCK (rho-associated protein kinase) but not Rac1 significantly reduced the invasive potential of laminin α3 knockdown cells. Knockdown of laminin subunits α3 and γ2 increased monocyte recruitment to the tumour microenvironment. However, only the loss of laminin α3 correlated with increased tumour-associated macrophages both in xenografted tumours and in patient tumour samples. CONCLUSIONS: These data provide evidence that loss of the laminin α3 chain in cSCC has an effect on both the epithelial and immune components of cSCC, resulting in an aggressive tumour microenvironment.


Subject(s)
Carcinoma, Squamous Cell , Laminin/genetics , Macrophages , Skin Neoplasms , Animals , Gene Knockdown Techniques , Humans , Immunohistochemistry , Mice , Neoplasm Transplantation , Tumor Microenvironment
12.
Ecol Evol ; 10(14): 6954-6966, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32760504

ABSTRACT

The relative roles of top-down (consumer-driven) and bottom-up (resource-driven) forcing in exploited marine ecosystems have been much debated. Examples from a variety of marine systems of exploitation-induced, top-down trophic forcing have led to a general view that human-induced predator perturbations can disrupt entire marine food webs, yet other studies that have found no such evidence provide a counterpoint. Though evidence continues to emerge, an unresolved debate exists regarding both the relative roles of top-down versus bottom-up forcing and the capacity of human exploitation to instigate top-down, community-level effects. Using time-series data for 104 reef communities spanning tropical to temperate Australia from 1992 to 2013, we aimed to quantify relationships among long-term trophic group population density trends, latitude, and exploitation status over a continental-scale biogeographic range. Specifically, we amalgamated two long-term monitoring databases of marine community dynamics to test for significant positive or negative trends in density of each of three key trophic levels (predators, herbivores, and algae) across the entire time series at each of the 104 locations. We found that trophic control tended toward bottom-up driven in tropical systems and top-down driven in temperate systems. Further, alternating long-term population trends across multiple trophic levels (a method of identifying trophic cascades), presumably due to top-down trophic forcing, occurred in roughly fifteen percent of locations where the prerequisite significant predator trends occurred. Such alternating trophic trends were significantly more likely to occur at locations with increasing predator densities over time. Within these locations, we found a marked latitudinal gradient in the prevalence of long-term, alternating trophic group trends, from rare in the tropics (<5% of cases) to relatively common in temperate areas (~45%). Lastly, the strongest trends in predator and algal density occurred in older no-take marine reserves; however, exploitation status did not affect the likelihood of alternating long-term trophic group trends occurring. Our data suggest that the type and degree of trophic forcing in this system are likely related to one or more covariates of latitude, and that ecosystem resiliency to top-down control does not universally vary in this system based on exploitation level.

13.
J Hum Evol ; 143: 102774, 2020 06.
Article in English | MEDLINE | ID: mdl-32325278

ABSTRACT

Functional comparisons of cortical bone strength properties between hominoid hallucal and pollical metapodials (Mt1 and Mc1, respectively) are lacking. Determining which of these two elements is stronger, and by how much, could be informative because the hallux and pollex are used differently both within and among extant hominoids during locomotion and manipulation (i.e., functional differentiation between autopod pairs). Here, we compare Mt1 and Mc1 midshaft cortical area, polar section modulus, and polar second moment of area, calculated from high-resolution computed tomography images in humans (n = 21), chimpanzees (n = 47), gorillas (n = 24), orangutans (n = 20), siamangs (n = 8), and gibbons (n = 21). Intraindividual comparisons between bones within species were made using paired t-tests. Log10-transformed Mt1:Mc1 ratios were created to assess relative strength asymmetry between bones, and interspecific comparisons of these proportions were made using analyses of variance. Absolute strength differences between the Mt1 and Mc1 for all variables were significantly larger in the Mt1 for all species (p < 0.05). Significant differences across species in Mt1:Mc1 proportions were also found, thereby demonstrating that strength asymmetry between bones differs among taxa (p < 0.05); asymmetry was lowest in orangutans, intermediate in gorillas, and greatest in humans, chimpanzees, siamangs, and gibbons. These findings support the hypothesis that the Mt1 is better adapted structurally than the Mc1 for bearing mechanical loads during weight support of locomotion in all extant hominoids and that pedal hallucal grasping likely engenders higher loads than manual pollical grasping in nonhuman hominoids. Thus, functional differentiation in autopod use within and among hominoids is reflected in hallucal and pollical metapodial strength properties.


Subject(s)
Hallux/physiology , Hominidae/physiology , Hylobatidae/physiology , Thumb/physiology , Animals , Biomechanical Phenomena , Female , Male , Shear Strength
14.
Glob Chang Biol ; 26(5): 2785-2797, 2020 05.
Article in English | MEDLINE | ID: mdl-32115808

ABSTRACT

Anticipating future changes of an ecosystem's dynamics requires knowledge of how its key communities respond to current environmental regimes. The Great Barrier Reef (GBR) is under threat, with rapid changes of its reef-building hard coral (HC) community structure already evident across broad spatial scales. While several underlying relationships between HC and multiple disturbances have been documented, responses of other benthic communities to disturbances are not well understood. Here we used statistical modelling to explore the effects of broad-scale climate-related disturbances on benthic communities to predict their structure under scenarios of increasing disturbance frequency. We parameterized a multivariate model using the composition of benthic communities estimated by 145,000 observations from the northern GBR between 2012 and 2017. During this time, surveyed reefs were variously impacted by two tropical cyclones and two heat stress events that resulted in extensive HC mortality. This unprecedented sequence of disturbances was used to estimate the effects of discrete versus interacting disturbances on the compositional structure of HC, soft corals (SC) and algae. Discrete disturbances increased the prevalence of algae relative to HC while the interaction between cyclones and heat stress was the main driver of the increase in SC relative to algae and HC. Predictions from disturbance scenarios included relative increases in algae versus SC that varied by the frequency and types of disturbance interactions. However, high uncertainty of compositional changes in the presence of several disturbances shows that responses of algae and SC to the decline in HC needs further research. Better understanding of the effects of multiple disturbances on benthic communities as a whole is essential for predicting the future status of coral reefs and managing them in the light of new environmental regimes. The approach we develop here opens new opportunities for reaching this goal.


Subject(s)
Anthozoa , Cyclonic Storms , Animals , Coral Reefs , Ecosystem
15.
Heart Lung ; 49(4): 377-380, 2020.
Article in English | MEDLINE | ID: mdl-32014313

ABSTRACT

INTRODUCTION: Atrial fibrillation (AFib) is a growing health concern, affecting more than 40 million patients worldwide and increasing stroke risk by five times. Community screening initiatives in rural healthcare establishments are becoming more feasible with the development of innovative, mobile-ECG (mECG) technology. The purpose of this research was to characterize increased rates of stroke risk factors and to determine AFib incidence in rural, pharmacy settings. METHODS: The researchers examined the prevalence of risk factors associated with AFib and calculated CHA2DS2-VASc stroke risk scores in a previously undiagnosed AFib community sample of 250 participants. Eligible participants at two rural pharmacies were administered a 1-lead mECG reading. Participants were then asked to complete questionnaires on demographic and medical history information. All participants were given educational materials on AFib and medical referrals when indicated. RESULTS: Prevalence rates of six, known independent stroke risk factors (CHA2DS2-VASc scores: (2.68 ± 1.35)) were significantly higher in the study sample than reported national US averages. Screening via mECG indicated preliminary AFib rates of approximately 4%; however, upon independent adjudication of the readings from three electrophysiologists AFib prevalence ranged between 1% and 8%. DISCUSSION: Collectively, an alarming rate of untreated stroke risk in a rural pharmacy sample was identified by the researchers utilizing mECG technology. These results suggest potential value to the use of mECG technology to screen for AFib in at-risk communities.


Subject(s)
Atrial Fibrillation , Pharmacies , Stroke , Atrial Fibrillation/diagnosis , Atrial Fibrillation/epidemiology , Electrocardiography , Humans , Risk Factors , Stroke/diagnosis , Stroke/epidemiology
16.
Pacing Clin Electrophysiol ; 43(2): 254-257, 2020 02.
Article in English | MEDLINE | ID: mdl-31953957

ABSTRACT

BACKGROUND: Medical technologies for consumers aim to help prevent, manage, and even forecast cardiovascular events, but their emotional impact is not fully known. The value of mobile-electrocardiogram (mECG) technology to an existing group of cardiac patients is unknown. The purpose of this study was to examine the impact of readily available mECG capability for a sample of implantable cardioverter defibrillator (ICD) patients. METHODS: Patients with ICDs (N = 51) were recruited and consented in a large academic cardiology clinic. Participants were given a mECG device and asked to take a 30-ss reading at least once per day for 30 days. Technology satisfaction, cardiac anxiety, shock anxiety, and ICD device acceptance were measured pre- and post-mECG usage. RESULTS: mECG technology was regularly used (M = 36.6 readings completed per month) and positively appraised by ICD patients (mean of 4.4 out of possible 5). Self-reported symptoms of general cardiac anxiety were not significantly affected by the utilization of mECG technology. ICD specific measures were mixed with increased overall ICD device acceptance but also increased shock anxiety. CONCLUSIONS: ICD patients positively viewed and used mECG technology regularly as prescribed. However, the overall psychological impact of mECG was mixed and suggests that ICD patients may have idiosyncratic adjustments to the increased access of cardiac device data.


Subject(s)
Defibrillators, Implantable/psychology , Electrocardiography, Ambulatory , Patient Acceptance of Health Care , Adult , Aged , Aged, 80 and over , Anxiety/psychology , Female , Humans , Male , Middle Aged , Quality of Life/psychology
17.
J Therm Biol ; 86: 102433, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31789230

ABSTRACT

The thermal microenvironments of corals is a topic of current interest given their relationship to coral bleaching. We present computational fluid dynamics (CFD) model of corals with both smooth and rugged polyp surface topographies for two species of massive corals (Leptastrea purpurea and Platygyra sinensis) in order to predict their microscale surface warming. This study explores whether variation in polyp depth (PD) may directly effect a coral overall surface area-to-volume (A/V) ratio and consequently its surface warming. Validation of our models was made against detailed laboratory measurements of coral surface warming and thermal boundary layer thickness. Our results suggested that while differences in surface warming exist between smooth surfaces and surfaces covered in micro-polyps (5 mm depth), the variation in terms of surface warming is small (~0.18-0.19∘C) and it can be largely attributed to increasing A/V ratios. Our results demonstrated good agreement with measurements of surface temperatures on living corals and that ignoring the presence of polyps by modelling heat transfer associated with a smooth surface makes no material difference to the values obtained or the interpretation of the processes leading to surface warming.


Subject(s)
Anthozoa , Models, Theoretical , Thermal Conductivity , Animals , Hot Temperature , Hydrodynamics , Surface Properties
18.
Biol Lett ; 15(10): 20190493, 2019 10 31.
Article in English | MEDLINE | ID: mdl-31662067

ABSTRACT

Natural environmental gradients encompass systematic variation in abiotic factors that can be exploited to test competing explanations of biodiversity patterns. The species-energy (SE) hypothesis attempts to explain species richness gradients as a function of energy availability. However, limited empirical support for SE is often attributed to idiosyncratic, local-scale processes distorting the underlying SE relationship. Meanwhile, studies are also often confounded by factors such as sampling biases, dispersal boundaries and unclear definitions of energy availability. Here, we used spatially structured observations of 8460 colonies of photo-symbiotic reef-building corals and a null-model to test whether energy can explain observed coral species richness over depth. Species richness was left-skewed, hump-shaped and unrelated to energy availability. While local-scale processes were evident, their influence on species richness was insufficient to reconcile observations with model predictions. Therefore, energy availability, either in isolation or in combination with local deterministic processes, was unable to explain coral species richness across depth. Our results demonstrate that local-scale processes do not necessarily explain deviations in species richness from theoretical models, and that the use of idiosyncratic small-scale factors to explain large-scale ecological patterns requires the utmost caution.


Subject(s)
Anthozoa , Animals , Biodiversity , Ecology , Models, Biological
20.
PLoS Biol ; 17(8): e3000366, 2019 08.
Article in English | MEDLINE | ID: mdl-31386657

ABSTRACT

Since the 1950s, industrial fisheries have expanded globally, as fishing vessels are required to travel further afield for fishing opportunities. Technological advancements and fishery subsidies have granted ever-increasing access to populations of sharks, tunas, billfishes, and other predators. Wilderness refuges, defined here as areas beyond the detectable range of human influence, are therefore increasingly rare. In order to achieve marine resources sustainability, large no-take marine protected areas (MPAs) with pelagic components are being implemented. However, such conservation efforts require knowledge of the critical habitats for predators, both across shallow reefs and the deeper ocean. Here, we fill this gap in knowledge across the Indo-Pacific by using 1,041 midwater baited videos to survey sharks and other pelagic predators such as rainbow runner (Elagatis bipinnulata), mahi-mahi (Coryphaena hippurus), and black marlin (Istiompax indica). We modeled three key predator community attributes: vertebrate species richness, mean maximum body size, and shark abundance as a function of geomorphology, environmental conditions, and human pressures. All attributes were primarily driven by geomorphology (35%-62% variance explained) and environmental conditions (14%-49%). While human pressures had no influence on species richness, both body size and shark abundance responded strongly to distance to human markets (12%-20%). Refuges were identified at more than 1,250 km from human markets for body size and for shark abundance. These refuges were identified as remote and shallow seabed features, such as seamounts, submerged banks, and reefs. Worryingly, hotpots of large individuals and of shark abundance are presently under-represented within no-take MPAs that aim to effectively protect marine predators, such as the British Indian Ocean Territory. Population recovery of predators is unlikely to occur without strategic placement and effective enforcement of large no-take MPAs in both coastal and remote locations.


Subject(s)
Aquatic Organisms/growth & development , Conservation of Natural Resources/methods , Predatory Behavior/physiology , Animals , Body Size , Coral Reefs , Ecosystem , Food Supply/methods , Pacific Ocean , Seafood , Wilderness
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