960 resultados para 1604 Human Geography


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Separately, actinic keratosis (AK) and cutaneous squamous cell carcinoma (SCC) have been associated with cutaneous human papillomavirus (HPV) infections. To further explore the association between HPV infection and SCC development, we determined markers of cutaneous HPV infection within a single population in persons with precursor lesions (AK), cancerous lesions (SCC), and without. Serum and plucked eyebrow hairs were collected from 57 tumor-free controls, 126 AK, and 64 SCC cases. Presence of HPV L1 and E6 seroreactivity and viral DNA were determined for HPV types 5, 8, 15, 16, 20, 24, and 38. Significant positive associations with increasing severity of the lesions (controls, AK, and SCC, respectively) were observed for overall HPV L1 seropositivity (13%, 26%, and 37%) and for HPV8 (4%, 17%, and 30%). In parallel, the proportion of L1 seropositive individuals against multiple HPV types increased from 14% to 39% and 45%. The overall E6 seroreactivity, however, tended to decline with AK and SCC, especially for HPV8 (21%, 11%, and 2%). HPV DNA positivity was most prevalent in the AK cases (54%) compared with the SCC cases (44%) and the tumor-free controls (40%). Among all participants, there was a positive trend between overall HPV DNA positivity and L1 seropositivity, but not E6 seropositivity. Taken together, our data suggest that cutaneous HPV infections accompanied by detectable HPV DNA in eyebrow hairs and HPV L1 seropositivity, but not E6 seropositivity, are associated with an increased risk of AK and SCC.

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Human papillomaviruses (HPVs) cause cervical cancer and some other types of epithelial cancers. HPV types from the phylogenic beta genus (beta-PVs), formerly known as epidermodysplasia verruciformis–associated HPV types, are frequently detected in nonmelanoma skin cancers, especially in squamous cell carcinomas (SCCs). An etiologic relationship with beta-PV infection is suspected...

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Eph receptor tyrosine kinases and their ligands, the ephrins, regulate the development and maintenance of multiple organs but little is known about their potential role within the cornea. The purpose of this study was to perform a thorough investigation of Eph/ephrin expression within the human cornea including the limbal stem cell niche. Initially, immunohistochemistry was performed on human donor eyes to determine the spatial distribution of Eph receptors and ephrins in the cornea and limbus. Patterns of Eph/ephrin gene expression in (1) immortalised human corneal endothelial (B4G12) or corneal epithelial (HCE-T) cell lines, and (2) primary cultures of epithelial or stromal cells established from the corneal limbus of cadaveric eye tissue were then assessed by reverse transcription (RT) PCR. Limbal epithelial or stromal cells from primary cultures were also assessed for evidence of Eph/ephrin-reactivity by immunofluorescence. Immunoreactivity for ephrinA1 and EphB4 was detected in the corneal endothelium of donor eyes. EphB4 was also consistently detected in the limbal and corneal epithelium and in cells located in the stroma of the peripheral cornea. Expression of multiple Eph/ephrin genes was detected in immortalised corneal epithelial and endothelial cell lines. Evidence of Eph/ephrin gene expression was also demonstrated in primary cultures of human limbal stromal (EphB4, B6; ephrinA5) and epithelial cells (EphA1, A2; ephrinA5, B2) using both RT-PCR and immunofluorescence. The expression of Eph receptors and ephrins within the human cornea and limbus is much wider than previously appreciated and suggests multiple potential roles for these molecules in the maintenance of normal corneal architecture.

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Adolescent idiopathic scoliosis is a complex three dimensional deformity affecting 2-3% of the general population. The resulting spinal deformity consists of coronal curvature, hypokyphosis of the thoracic spine and vertebral rotation in the axial plane with posterior elements turned into the curve concavity. The potential for curve progression is heightened during the adolescent growth spurt. Success of scoliosis deformity correction depends on solid bony fusion between adjacent vertebrae after the intervertebral (IV) discs have been surgically cleared and the disc spaces filled with graft material. Recently a bioactive and resorbable scaffold fabricated from medical grade polycaprolactone has been developed for bone regeneration at load bearing sites. Combined with rhBMP-2, this has been shown to be successful in acting as a bone graft substitute in a porcine lumbar interbody fusion model when compared to autologous bone graft alone. The study aimed to establish a large animal thoracic spine interbody fusion model, develop spine biodegradable scaffolds (PCL) in combination with biologics (rhBMP-2) and to establish a platform for research into spine tissue engineering constructs. Preliminary results demonstrate higher grades of radiologically evident bony fusion across all levels when comparing fusion scores between the 3 and 6 month postop groups at the PCL CaP coated scaffold level, which is observed to be a similar grade to autograft, while no fusion is seen at the scaffold only level. Results to date suggest that the combination of rhBMP-2 and scaffold engineering actively promotes bone formation, laying the basis of a viable tissue engineered constructs.

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Many commentators have treated the internet as a site of democratic freedom and as a new kind of public sphere. While there are good reasons for optimism, like any social space digital space also has its dark side. Citizens and governments alike have expressed anxiety about cybercrime and cyber-security. In August 2011, the Australian government introduced legislation to give effect to Australia becoming a signatory to the European Convention on Cybercrime (2001). At the time of writing, that legislation is still before the Parliament. In this article, attention is given to how the legal and policy-making process enabling Australia to be compliant with the European Convention on Cybercrime came about. Among the motivations that informed both the development of the Convention in Europe and then the Australian exercise of legislating for compliance with it was a range of legitimate concerns about the impact that cybercrime can have on individuals and communities. This article makes the case that equal attention also needs to be given to ensuring that legislators and policy makers differentiate between legitimate security imperatives and any over-reach evident in the implementation of this legislation that affects rule of law principles, our capacity to engage in democratic practices, and our civic and human rights.

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This discussion has outlined a theoretical and pragmatic framework to demonstrate that future research involving the analysis of human performance in surgical should encourage the use of phenomenology to enhance the knowledge base of this area of study. Merging experiential (first-person) and experimental (third-person) methods may possibly help improve research designs and analyses in the investigation of robotics in surgical performance. By relying solely on third-person techniques, the current methodology and interpretation used to analyze human performance in surgical robotics is limited. Recent advances in cognitive science and psychology have also recognized this limitation and have now begun to shift to neurophenomenology. Finally, discussion on recent robotics research presented here demonstrates the potential phenomenology holds for augmenting the methodological and analysis techniques currently used by researchers of human performance in surgical robotics.

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The human kallikrein-related peptidases are a subgroup of trypsin and chymotrypsin-like serine peptidases that are characterized by their homology to tissue kallikrein or kallikrein 1 (KLK1) encoded by the KLK1 gene (reviewed in[1-4]). The human KLK locus spans an approximately 320 kb region on chromosome 19q13.3-13.4 and contains fifteen genes encoding KLK1 and fourteen other kallikrein-related peptidases, KLK2-KLK15, which have been named contiguously in the locus in the order of their discovery [5-8] (Figure 606.1). It is the largest contiguous cluster of serine protease encoding genes in the human genome which has evolved from gene duplication of KLK1 and then subsequent reduplication of the newly evolved KLK genes [2]. The high conservation noted for KLK1-KLK3 (62-77%) reflects the proposed duplication of the KLK1 gene that produced the KLK2 gene which further generated the KLK3 gene. In contrast, the newer KLK4-KLK15 proteases share much less similarity, from 24-66%, although strong homology between KLK4 and KLK5, KLK9 and KLK11, and KLK10 and KLK12 suggests these genes are duplications of each other [2]...

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Understanding complex systems within the human body presents a unique challenge for medical engineers and health practitioners. One significant issue is the ability to communicate their research findings to audiences with limited medical knowledge or understanding of the behaviour and composition of such structures. Much of what is known about the human body is currently communicated through abstract representations which include raw data sets, hand drawn illustrations or cellular automata. The development of 3D Computer Graphics Animation has provided a new medium for communicating these abstract concepts to audiences in new ways. This paper presents an approach for the visualisation of human articular cartilage deterioration using 3D Computer Graphics Animation. The animated outcome of this research introduces the complex interior structure of human cartilage to audiences with limited medical engineering knowledge.

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Service robots that operate in human environments will accomplish tasks most efficiently and least disruptively if they have the capability to mimic and understand the motion patterns of the people in their workspace. This work demonstrates how a robot can create a humancentric navigational map online, and that this map re ects changes in the environment that trigger altered motion patterns of people. An RGBD sensor mounted on the robot is used to detect and track people moving through the environment. The trajectories are clustered online and organised into a tree-like probabilistic data structure which can be used to detect anomalous trajectories. A costmap is reverse engineered from the clustered trajectories that can then inform the robot's onboard planning process. Results show that the resultant paths taken by the robot mimic expected human behaviour and can allow the robot to respond to altered human motion behaviours in the environment.

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Abstract: The paper investigates the geographical mobility of creative workers in China,focusing on the authors’ survey of workers in the animation industry. More specifically,the authors use the Reilly-Converse model and GIS tools to probe the locational choices of Chinese animation workers in Beijing and Shanghai by analyzing such factors of spatial attractiveness as home town, place of residence, and university from which the worker graduated. The paper compares the creative milieus in Beijing and Shanghai, and demonstrates that the “personal trajectory” of human capital is a key determinant of occupational location. The results of the authors’ survey highlight the limitations of Richard Florida’s 3T theory in the Chinese context.

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We blend research from human-computer interface (HCI) design with computational based crypto- graphic provable security. We explore the notion of practice-oriented provable security (POPS), moving the focus to a higher level of abstraction (POPS+) for use in providing provable security for security ceremonies involving humans. In doing so we high- light some challenges and paradigm shifts required to achieve meaningful provable security for a protocol which includes a human. We move the focus of security ceremonies from being protocols in their context of use, to the protocols being cryptographic building blocks in a higher level protocol (the security cere- mony), which POPS can be applied to. In order to illustrate the need for our approach, we analyse both a protocol proven secure in theory, and a similar proto- col implemented by a �nancial institution, from both HCI and cryptographic perspectives.

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This paper will focus on the legal issues associated with people displaced as a result of water scarcity. Human displacement can lead to internal displacement (displacement of people within their country) and external displacement (displacement of people into another country). If the displacement takes place as a result of climate change these people may be referred to as climate refugees. The majority of work on climate refugees has focused on those people that will lose their homes as a result of sea –level rise. The number of people that could be displaced as a result of prolonged drought and lack of adequate water supplies is likely to be far more significant in number. There are estimates that around 2.8 billion people will suffer water shortages by 2025 and many of these people are at increased risk of internal or external displacement. Certain groups are more likely to be displaced as a result of prolonged drought or water scarcity. These groups include indigenous and minorities groups living in areas that are more susceptible to climate change and groups living in areas with a history of water shortage and supply issues. People displaced as a result of water scarcity are at increased risks of malnutrition and of dehydration. Furthermore the lack of adequate water supplies in such areas increases the risk and spread of disease among the population. In certain instances internal and external displacement may lead to escalation of conflict and competition for water resources in newly settled territories. This paper will use case studies from Australia (indigenous groups and rural landholders) and East Africa (Ethiopia, Sudan and Kenya) to demonstrate the significance of human displacement arising as a result of water scarcity. Climate adaptation policy frameworks will need to address a number of legal issues, arising as a result of climate displacement from water scarcity. There are a number of unresolved legal issues for both categories of environmental displaced people. The major legal issue for externally environmentally displaced people is lack of international recognition and support for these people. The Climate Change Convention, the Refugee Convention, the Desertification Convention and Human Rights instruments all fail to provide recognition for people externally displaced as a result of environmental conditions. Similarly there is a lack of legal recognition and legal support mechanisms to assist those people internally displaced by environmental conditions. The lack of developed environmental rights in most countries contributes to this problem. Polices and governance frameworks must be put in place which aims to prevent such displacement through programs identifying populations at risk and instigating damage mitigation and relocation programs. In addition there are a number of legal issues which may arise such as; rights of compensation, property and tenure disputes, increases on the water demand and environmental degradation in places of relocation and jurisdictional issues arising in federal countries. This paper will provide an overview of the legal issues at the international and national levels arising as a result of climate displacement from water scarcity.  

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Bovine colostrum has been shown to influence the cytokine production of bovine leukocytes. However, it remains unknown whether processed bovine colostrum, a supplement popular among athletes to enhance immune function, is able to modulate cytokine secretion of human lymphocytes and monocytes. The aim of this investigation was to determine the influence of a commercially available bovine colostrum protein concentrate (CPC) to stimulate cytokine production by human peripheral blood mononuclear cells (PBMCs). Blood was sampled from four healthy male endurance athletes who had abstained from exercise for 48 h. PBMCs were separated and cultured with bovine CPC concentrations of 0 (control), 1.25, 2.5, and 5% with and without lipopolysaccharide (LPS) (3 microg/mL) and phytohemagglutinin (PHA) (2.5 microg/mL). Cell supernatants were collected at 6 and 24 h of culture for the determination of tumor necrosis factor (TNF), interferon (IFN)-gamma, interleukin (IL)-10, IL-6, IL-4, and IL-2 concentrations. Bovine CPC significantly stimulated the release of IFN-gamma, IL-10, and IL-2 (p < 0.03). The addition of LPS to PBMCs cocultured with bovine CPC significantly stimulated the release of IL-2 and inhibited the early release of TNF, IL-6, and IL-4 (p < 0.02). Phytohemagglutinin stimulation in combination with bovine CPC significantly increased the secretion of IL-10 and IL-2 at 6 h of culture and inhibited IFN-gamma and TNF (p < 0.05). This data show that a commercial bovine CPC is able to modulate in vitro cytokine production of human PBMCs. Alterations in cytokine secretion may be a potential mechanism for reported benefits associated with supplementation.

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CC-chemokine receptor 2 (CCR2) and its ligand, monocyte chemotactic protein-1 (MCP-1, also known as CCL2), are crucial for the recruitment of monocytes/macrophages to sites of inflammation. We conducted a series of experiments to investigate the relationship between stress, monocyte CCR2 expression and migration activity. First, we collected peripheral blood mononuclear cells (PBMC) from untrained subjects (n=8) and measured CCR2 expression on CD14(+) monocytes cultured with cortisol, epinephrine and norepinephrine. Second, we collected PBMC from the subjects before and after they cycled for 60 min at 70% peak O(2) uptake (VO2(peak)), and measured alterations in CCR2 expression on monocytes following exercise. Third, we cultured PBMC with serum obtained before and after exercise and the glucocorticoid antagonist RU-486 to determine the effect of cortisol on CCR2 expression in vitro. Last, we measured the ability of PBMC treated with serum or cortisol to migrate through membrane filters in response to CCL2. Cortisol (but not epinephrine or norepinephrine) increased CCR2 expression on monocytes in a dose- and time-dependent manner. Exercise did not influence CCR2 expression on PBMC, whereas incubation of PBMC with post-exercise serum significantly increased CCR2 expression. Both cortisol and post-exercise serum increased the migration of PBMC toward CCL2. The increase in CCR2 expression on PBMC following stimulation with cortisol and serum was blocked by the glucocorticoid receptor antagonist RU-486. In conclusion, cortisol released during exercise increased monocyte CCR2 expression and migration activity in vitro. These alterations may influence inflammation and regeneration of damaged tissue after acute stress.

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Purpose: IpRGCs mediate non-image forming functions including photoentrainment and the pupil light reflex (PLR). Temporal summation increases visual sensitivity and decreases temporal resolution for image forming vision, but the summation properties of nonimage forming vision are unknown. We investigated the temporal summation of inner (ipRGC) and outer (rod/cone) retinal inputs to the PLR. Method: The consensual PLR of the left eye was measured in six participants with normal vision using a Maxwellian view infrared pupillometer. Temporal summation was investigated using a double-pulse protocol (100 ms stimulus pairs; 0–1024 ms inter-stimulus interval, ISI) presented to the dilated fellow right eye (Tropicamide 1%). Stimulus lights (blue λmax = 460 nm; red λmax = 638 nm) biased activity to inneror outer retinal inputs to non-image forming vision. Temporal summation was measured suprathreshold (15.2 log photons.cm−2.s−1 at the cornea) and subthreshold (11.4 log photons.cm−2.s−1 at the cornea). Results: RM-ANOVAs showed the suprathreshold and subthreshold 6 second post illumination pupil response (PIPR: expressed as percentage baseline diameter) did not significantly vary for red or blue stimuli (p > .05). The PIPR for a subthreshold red 16 ms double-pulse control condition did not significantly differ with ISI (p > .05). The maximum constriction amplitude for red and blue 100 ms double- pulse stimuli did not significantly vary with ISI (p > .05). Conclusion: The non-significant changes in suprathreshold PIPR and subthreshold maximum pupil constriction indicate that inner retinal ipRGC inputs and outer retinal photoreceptor inputs to the PLR do not show temporal summation. The results suggest a fundamental difference between the temporal summation characteristics of image forming and non-image forming vision.