924 resultados para facial expression recognition


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Robustness to variations in environmental conditions and camera viewpoint is essential for long-term place recognition, navigation and SLAM. Existing systems typically solve either of these problems, but invariance to both remains a challenge. This paper presents a training-free approach to lateral viewpoint- and condition-invariant, vision-based place recognition. Our successive frame patch-tracking technique infers average scene depth along traverses and automatically rescales views of the same place at different depths to increase their similarity. We combine our system with the condition-invariant SMART algorithm and demonstrate place recognition between day and night, across entire 4-lane-plus-median-strip roads, where current algorithms fail.

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Macrophages play a crucial role in the maintenance and resolution of inflammation and express a number of pro- and anti-inflammatory molecules in response to stressors. Among them, the complement receptor 5a (C5aR) plays an integral role in the development of inflammatory disorders. Biliverdin and bilirubin, products of heme catabolism, exert anti-inflammatory effects and inhibit complement activation. Here, we define the effects of biliverdin on C5aR expression in macrophages and the roles of Akt and mammalian target of rapamycin (mTOR) in these responses. Biliverdin administration inhibited lipopolysaccharide (LPS)-induced C5aR expression (without altering basal expression), an effect partially blocked by rapamycin, an inhibitor of mTOR signaling. Biliverdin also reduced LPS-dependent expression of the pro-inflammatory cytokines TNF-alpha and IL-6. Collectively, these data indicate that biliverdin regulates LPS-mediated expression of C5aR via the mTOR pathway, revealing an additional mechanism underlying biliverdin's anti-inflammatory effects.

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The benefits for university graduates in growing skills and capabilities through volunteering experiences are gaining increased attention. Building leadership self-efficacy supports students develop their capacity for understanding, articulating and evidencing their learning. Reward and recognition is fundamental in the student’s journey to build self-efficacy. Through this research, concepts of reward and recognition have been explored and articulated through the experiences and perceptions of actively engaged student peer leaders. The research methodology has enabled a collaborative, student-centred approach in shaping an innovative Rewards Framework, which supports, recognises and rewards the learning journey from beginning peer leader to competent and confident graduate.

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Background The EphB4 receptor tyrosine kinase is overexpressed in many cancers including prostate cancer. The molecular mechanisms by which this ephrin receptor influences cancer progression are complex as there are tumor-promoting ligand-independent mechanisms in place as well as ligand-dependent tumor suppressive pathways. Methods We employed transient knockdown of EPHB4 in prostate cancer cells, coupled with gene microarray analysis, to identify genes that were regulated by EPHB4 and may represent linked tumor-promoting factors. We validated target genes using qRT-PCR and employed functional assays to determine their role in prostate cancer migration and invasion. Results We discovered that over 500 genes were deregulated upon EPHB4 siRNA knockdown, with integrin β8 (ITGB8) being the top hit (29-fold down-regulated compared to negative non-silencing siRNA). Gene ontology analysis found that the process of cell adhesion was highly deregulated and two other integrin genes, ITGA3 and ITGA10, were also differentially expressed. In parallel, we also discovered that over-expression of EPHB4 led to a concomitant increase in ITGB8 expression. In silico analysis of a prostate cancer progression microarray publically available in the Oncomine database showed that both EPHB4 and ITGB8 are highly expressed in prostatic intraepithelial neoplasia, the precursor to prostate cancer. Knockdown of ITGB8 in PC-3 and 22Rv1 prostate cancer cells in vitro resulted in significant reduction of cell migration and invasion. Conclusions These results reveal that EphB4 regulates integrin β8 expression and that integrin β8 plays a hitherto unrecognized role in the motility of prostate cancer cells and thus targeting integrin β8 may be a new treatment strategy for prostate cancer.

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Place recognition has long been an incompletely solved problem in that all approaches involve significant compromises. Current methods address many but never all of the critical challenges of place recognition – viewpoint-invariance, condition-invariance and minimizing training requirements. Here we present an approach that adapts state-of-the-art object proposal techniques to identify potential landmarks within an image for place recognition. We use the astonishing power of convolutional neural network features to identify matching landmark proposals between images to perform place recognition over extreme appearance and viewpoint variations. Our system does not require any form of training, all components are generic enough to be used off-the-shelf. We present a range of challenging experiments in varied viewpoint and environmental conditions. We demonstrate superior performance to current state-of-the- art techniques. Furthermore, by building on existing and widely used recognition frameworks, this approach provides a highly compatible place recognition system with the potential for easy integration of other techniques such as object detection and semantic scene interpretation.

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2,4,6-trinitrotoluene (TNT) is one of the most commonly used nitro aromatic explosives in landmine, military and mining industry. This article demonstrates rapid and selective identification of TNT by surface-enhanced Raman spectroscopy (SERS) using 6-aminohexanethiol (AHT) as a new recognition molecule. First, Meisenheimer complex formation between AHT and TNT is confirmed by the development of pink colour and appearance of new band around 500 nm in UV-visible spectrum. Solution Raman spectroscopy study also supported the AHT:TNT complex formation by demonstrating changes in the vibrational stretching of AHT molecule between 2800-3000 cm−1. For surface enhanced Raman spectroscopy analysis, a self-assembled monolayer (SAM) of AHT is formed over the gold nanostructure (AuNS) SERS substrate in order to selectively capture TNT onto the surface. Electrochemical desorption and X-ray photoelectron studies are performed over AHT SAM modified surface to examine the presence of free amine groups with appropriate orientation for complex formation. Further, AHT and butanethiol (BT) mixed monolayer system is explored to improve the AHT:TNT complex formation efficiency. Using a 9:1 AHT:BT mixed monolayer, a very low detection limit (LOD) of 100 fM TNT was realized. The new method delivers high selectivity towards TNT over 2,4 DNT and picric acid. Finally, real sample analysis is demonstrated by the extraction and SERS detection of 302 pM of TNT from spiked.

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The QUT-NOISE-SRE protocol is designed to mix the large QUT-NOISE database, consisting of over 10 hours of back- ground noise, collected across 10 unique locations covering 5 common noise scenarios, with commonly used speaker recognition datasets such as Switchboard, Mixer and the speaker recognition evaluation (SRE) datasets provided by NIST. By allowing common, clean, speech corpora to be mixed with a wide variety of noise conditions, environmental reverberant responses, and signal-to-noise ratios, this protocol provides a solid basis for the development, evaluation and benchmarking of robust speaker recognition algorithms, and is freely available to download alongside the QUT-NOISE database. In this work, we use the QUT-NOISE-SRE protocol to evaluate a state-of-the-art PLDA i-vector speaker recognition system, demonstrating the importance of designing voice-activity-detection front-ends specifically for speaker recognition, rather than aiming for perfect coherence with the true speech/non-speech boundaries.

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We used event-related fMRI to investigate the neural correlates of encoding strength and word frequency effects in recognition memory. At test, participants made Old/New decisions to intermixed low (LF) and high frequency (HF) words that had been presented once or twice at study and to new, unstudied words. The Old/New effect for all hits vs. correctly rejected unstudied words was associated with differential activity in multiple cortical regions, including the anterior medial temporal lobe (MTL), hippocampus, left lateral parietal cortex and anterior left inferior prefrontal cortex (LIPC). Items repeated at study had superior hit rates (HR) compared to items presented once and were associated with reduced activity in the right anterior MTL. By contrast, other regions that had shown conventional Old/New effects did not demonstrate modulation according to memory strength. A mirror effect for word frequency was demonstrated, with the LF word HR advantage associated with increased activity in the left lateral temporal cortex. However, none of the regions that had demonstrated Old/New item retrieval effects showed modulation according to word frequency. These findings are interpreted as supporting single-process memory models proposing a unitary strength-like memory signal and models attributing the LF word HR advantage to the greater lexico-semantic context-noise associated with HF words due to their being experienced in many pre-experimental contexts.

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In the present study, items pre-exposed in a familiarization series were included in a list discrimination task to manipulate memory strength. At test, participants were required to discriminate strong targets and strong lures from weak targets and new lures. This resulted in a concordant pattern of increased "old" responses to strong targets and lures. Model estimates attributed this pattern to either equivalent increases in memory strength across the two types of items (unequal variance signal detection model) or equivalent increases in both familiarity and recollection (dual process signal detection [DPSD] model). Hippocampal activity associated with strong targets and lures showed equivalent increases compared with missed items. This remained the case when analyses were restricted to high-confidence responses considered by the DPSD model to reflect predominantly recollection. A similar pattern of activity was observed in parahippocampal cortex for high-confidence responses. The present results are incompatible with "noncriterial" or "false" recollection being reflected solely in inflated DPSD familiarity estimates and support a positive correlation between hippocampal activity and memory strength irrespective of the accuracy of list discrimination, consistent with the unequal variance signal detection model account.

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Inter-individual variation in facial shape is one of the most noticeable phenotypes in humans, and it is clearly under genetic regulation; however, almost nothing is known about the genetic basis of normal human facial morphology. We therefore conducted a genome-wide association study for facial shape phenotypes in multiple discovery and replication cohorts, considering almost ten thousand individuals of European descent from several countries. Phenotyping of facial shape features was based on landmark data obtained from three-dimensional head magnetic resonance images (MRIs) and two-dimensional portrait images. We identified five independent genetic loci associated with different facial phenotypes, suggesting the involvement of five candidate genes-PRDM16, PAX3, TP63, C5orf50, and COL17A1-in the determination of the human face. Three of them have been implicated previously in vertebrate craniofacial development and disease, and the remaining two genes potentially represent novel players in the molecular networks governing facial development. Our finding at PAX3 influencing the position of the nasion replicates a recent GWAS of facial features. In addition to the reported GWA findings, we established links between common DNA variants previously associated with NSCL/P at 2p21, 8q24, 13q31, and 17q22 and normal facial-shape variations based on a candidate gene approach. Overall our study implies that DNA variants in genes essential for craniofacial development contribute with relatively small effect size to the spectrum of normal variation in human facial morphology. This observation has important consequences for future studies aiming to identify more genes involved in the human facial morphology, as well as for potential applications of DNA prediction of facial shape such as in future forensic applications.

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Speech recognition can be improved by using visual information in the form of lip movements of the speaker in addition to audio information. To date, state-of-the-art techniques for audio-visual speech recognition continue to use audio and visual data of the same database for training their models. In this paper, we present a new approach to make use of one modality of an external dataset in addition to a given audio-visual dataset. By so doing, it is possible to create more powerful models from other extensive audio-only databases and adapt them on our comparatively smaller multi-stream databases. Results show that the presented approach outperforms the widely adopted synchronous hidden Markov models (HMM) trained jointly on audio and visual data of a given audio-visual database for phone recognition by 29% relative. It also outperforms the external audio models trained on extensive external audio datasets and also internal audio models by 5.5% and 46% relative respectively. We also show that the proposed approach is beneficial in noisy environments where the audio source is affected by the environmental noise.

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Redclaw crayfish, Cherax quadricarinatus, possess a number of biological and commercial attributes that make them ideal for commercial aquaculture. While some studies have investigated digestive enzyme activity and nutritional requirements of this species, little information exists about the expression of digestive enzyme genes and their role in regulating digestive capacity. The current study therefore sequenced and annotated a RNASeq library constructed from a redclaw hepatopancreas to identify genes involved in digestive enzyme production. We observed that most of the transcripts that were annotated as digestive enzyme genes are associated with carbohydrate metabolism, thus confirming that redclaw have an innate capacity to digest a range of carbohydrate substrates. While endoglucanases were the most abundant group of digestive enzymes found, a number of novel transcripts were also detected. Here, we provide the first report for the presence and expression of endo-b-mannanase in freshwater crayfish. This novel gene showed significant alignment with a GH5 family protein from marine Limnoriids, wood borers that do not possess symbiotic microbes in their gut system. Overall, the data generated here provide an important resource to better understand the suite of digestive enzymes in redclaw that are very useful to fully utilize the species’ digestive capacity and will assist development of specific artificial feeds.

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Changes in water quality parameters such as pH and salinity can have a significant effect on productivity of aquaculture species. Similarly, relative osmotic pressure influences various physiological processes and regulates expression of a number of osmoregulatory genes. Among those, carbonic anhydrase (CA) plays a key role in systemic acid–base balance and ion regulation. Redclaw crayfish (Cherax quadricarinatus) are unique in their ability to thrive in environments with naturally varied pH levels, suggesting unique adaptation to pH stress. To date, however, no studies have focused on identification and characterisation of CA or other osmoregulatory genes in C. quadricarinatus. Here, we analysed the redclaw gill transcriptome and characterized CA genes along with a number of other key osmoregulatory genes that were identified in the transcriptome. We also examined patterns of gene expression of these CA genes when exposed to three pH treatments. In total, 72,382,710 paired end Illumina reads were assembled into 36,128 contigs with an average length of 800 bp. Approximately 37% of contigs received significant BLAST hits and 22% were assigned gene ontology terms. Three full length CA isoforms; cytoplasmic CA (ChqCAc), glycosyl-phosphatidylinositol-linked CA (ChqCAg), and β-CA (ChqCA-beta) as well as two partial CA gene sequences were identified. Both partial CA genes showed high similarity to ChqCAg and appeared to be duplicated from the ChqCAg. Full length coding sequences of Na+/K+-ATPase, V-type H+-ATPase, sarcoplasmic Ca+-ATPase, arginine kinase, calreticulin and Cl− channel protein 2 were also identified. Only the ChqCAc gene showed significant differences in expression across the three pH treatments. These data provide valuable information on the gill expressed CA genes and their expression patterns in freshwater crayfish. Overall our data suggest an important role for the ChqCAc gene in response to changes in pH and in systemic acid–base balance in freshwater crayfish.

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“If Hollywood could order intellectual property laws for Christmas, what would they look like? This is pretty close.” David Fewer “While European and American IP maximalists have pushed for TRIPS-Plus provisions in FTAs and bilateral agreements, they are now pushing for TRIPS-Plus-Plus protections in these various forums.” Susan Sell “ACTA is a threat to the future of a free and open Internet.” Alexander Furnas “Implementing the agreement could open a Pandora's box of potential human rights violations.” Amnesty International. “I will not take part in this masquerade.” Kader Arif, Rapporteur for the Anti-Counterfeiting Trade Agreement 2011 in the European Parliament Executive Summary As an independent scholar and expert in intellectual property, I am of the view that the Australian Parliament should reject the adoption of the Anti-Counterfeiting Trade Agreement 2011. I would take issue with the Department of Foreign Affairs and Trade’s rather partisan account of the negotiations, the consultations, and the outcomes associated with the Anti-Counterfeiting Trade Agreement 2011. In my view, the negotiations were secretive and biased; the local consultations were sometimes farcical because of the lack of information about the draft texts of the agreement; and the final text of the Anti-Counterfeiting Trade Agreement 2011 is not in the best interests of Australia, particularly given that it is a net importer of copyright works and trade mark goods and services. I would also express grave reservations about the quality of the rather pitiful National Interest Analysis – and the lack of any regulatory impact statement – associated with the Anti-Counterfeiting Trade Agreement 2011. The assertion that the Anti-Counterfeiting Trade Agreement 2011 does not require legislative measures is questionable – especially given the United States Trade Representative has called the agreement ‘the highest-standard plurilateral agreement ever achieved concerning the enforcement of intellectual property rights.’ It is worthwhile reiterating that there has been much criticism of the secretive and partisan nature of the negotiations surrounding the Anti-Counterfeiting Trade Agreement 2011. Sean Flynn summarizes these concerns: "The negotiation process for ACTA has been a case study in establishing the conditions for effective industry capture of a lawmaking process. Instead of using the relatively transparent and inclusive multilateral processes, ACTA was launched through a closed and secretive “‘club approach’ in which like-minded jurisdictions define enforcement ‘membership’ rules and then invite other countries to join, presumably via other trade agreements.” The most influential developing countries, including Brazil, India, China and Russia, were excluded. Likewise, a series of manoeuvres ensured that public knowledge about the specifics of the agreement and opportunities for input into the process were severely limited. Negotiations were held with mere hours notice to the public as to when and where they would be convened, often in countries half away around the world from where public interest groups are housed. Once there, all negotiation processes were closed to the public. Draft texts were not released before or after most negotiating rounds, and meetings with stakeholders took place only behind closed doors and off the record. A public release of draft text, in April 2010, was followed by no public or on-the-record meetings with negotiators." Moreover, it is disturbing that the Anti-Counterfeiting Trade Agreement 2011 has been driven by ideology and faith, rather than by any evidence-based policy making Professor Duncan Matthews has raised significant questions about the quality of empirical evidence used to support the proposal of Anti-Counterfeiting Trade Agreement 2011: ‘There are concerns that statements about levels of counterfeiting and piracy are based either on customs seizures, with the actual quantities of infringing goods in free circulation in any particular market largely unknown, or on estimated losses derived from industry surveys.’ It is particularly disturbing that, in spite of past criticism, the Department of Foreign Affairs and Trade has supported the Anti-Counterfeiting Trade Agreement 2011, without engaging the Productivity Commission or the Treasury to do a proper economic analysis of the proposed treaty. Kader Arif, Rapporteur for the Anti-Counterfeiting Trade Agreement 2011 in the European Parliament, quit his position, and said of the process: "I want to denounce in the strongest possible manner the entire process that led to the signature of this agreement: no inclusion of civil society organisations, a lack of transparency from the start of the negotiations, repeated postponing of the signature of the text without an explanation being ever given, exclusion of the EU Parliament's demands that were expressed on several occasions in our assembly. As rapporteur of this text, I have faced never-before-seen manoeuvres from the right wing of this Parliament to impose a rushed calendar before public opinion could be alerted, thus depriving the Parliament of its right to expression and of the tools at its disposal to convey citizens' legitimate demands.” Everyone knows the ACTA agreement is problematic, whether it is its impact on civil liberties, the way it makes Internet access providers liable, its consequences on generic drugs manufacturing, or how little protection it gives to our geographical indications. This agreement might have major consequences on citizens' lives, and still, everything is being done to prevent the European Parliament from having its say in this matter. That is why today, as I release this report for which I was in charge, I want to send a strong signal and alert the public opinion about this unacceptable situation. I will not take part in this masquerade." There have been parallel concerns about the process and substance of the Anti-Counterfeiting Trade Agreement 2011 in the context of Australia. I have a number of concerns about the substance of the Anti-Counterfeiting Trade Agreement 2011. First, I am concerned that the Anti-Counterfeiting Trade Agreement 2011 fails to provide appropriate safeguards in respect of human rights, consumer protection, competition, and privacy laws. It is recommended that the new Joint Parliamentary Committee on Human Rights investigate this treaty. Second, I argue that there is a lack of balance to the copyright measures in the Anti-Counterfeiting Trade Agreement 2011 – the definition of piracy is overbroad; the suite of civil remedies, criminal offences, and border measures is excessive; and there is a lack of suitable protection for copyright exceptions, limitations, and remedies. Third, I discuss trade mark law, intermediary liability, and counterfeiting. I express my concerns, in this context, that the Anti-Counterfeiting Trade Agreement 2011 could have an adverse impact upon consumer interests, competition policy, and innovation in the digital economy. I also note, with concern, the lobbying by tobacco industries for the Anti-Counterfeiting Trade Agreement 2011 – and the lack of any recognition in the treaty for the capacity of countries to take measures of tobacco control under the World Health Organization Framework Convention on Tobacco Control. Fourth, I note that the Anti-Counterfeiting Trade Agreement 2011 provides no positive obligations to promote access to essential medicines. It is particularly lamentable that Australia and the United States of America have failed to implement the Doha Declaration on the TRIPS Agreement and Public Health 2001 and the WTO General Council Decision 2003. Fifth, I express concerns about the border measures in the Anti-Counterfeiting Trade Agreement 2011. Such measures lack balance – and unduly favour the interests of intellectual property owners over consumers, importers, and exporters. Moreover, such measures will be costly, as they involve shifting the burden of intellectual property enforcement to customs and border authorities. Interdicting, seizing, and destroying goods may also raise significant trade issues. Finally, I express concern that the Anti-Counterfeiting Trade Agreement 2011 undermines the role of existing international organisations, such as the United Nations, the World Intellectual Property Organization and the World Trade Organization, and subverts international initiatives such as the WIPO Development Agenda 2007. I also question the raison d'être, independence, transparency, and accountability of the proposed new ‘ACTA Committee’. In this context, I am concerned by the shift in the position of the Labor Party in its approach to international treaty-making in relation to intellectual property. The Australian Parliament adopted the Australia-United States Free Trade Agreement 2004, which included a large Chapter on intellectual property. The treaty was a ‘TRIPs-Plus’ agreement, because the obligations were much more extensive and prescriptive than those required under the multilateral framework established by the TRIPS Agreement 1994. During the debate over the Australia-United States Free Trade Agreement 2004, the Labor Party expressed the view that it would seek to mitigate the effects of the TRIPS-Plus Agreement, when at such time it gained power. Far from seeking to ameliorate the effects of the Australia-United States Free Trade Agreement 2004, the Labor Government would seek to lock Australia into a TRIPS-Double Plus Agreement – the Anti-Counterfeiting Trade Agreement 2011. There has not been a clear political explanation for this change in approach to international intellectual property. For both reasons of process and substance, I conclude that the Australian Parliament and the Australian Government should reject the Anti-Counterfeiting Trade Agreement 2011. The Australian Government would do better to endorse the Washington Declaration on Intellectual Property and the Public Interest 2011, and implement its outstanding obligations in respect of access to knowledge, access to essential medicines, and the WIPO Development Agenda 2007. The case study of the Anti-Counterfeiting Trade Agreement 2011 highlights the need for further reforms to the process by which Australia engages in international treaty-making.

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Purpose Optical blur and ageing are known to affect driving performance but their effects on drivers' eye movements are poorly understood. This study examined the effects of optical blur and age on eye movement patterns and performance on the DriveSafe slide recognition test which is purported to predict fitness to drive. Methods Twenty young (27.1 ± 4.6 years) and 20 older (73.3 ± 5.7 years) visually normal drivers performed the DriveSafe under two visual conditions: best-corrected vision and with +2.00 DS blur. The DriveSafe is a Visual Recognition Slide Test that consists of brief presentations of static, real-world driving scenes containing different road users (pedestrians, bicycles and vehicles). Participants reported the types, relative positions and direction of travel of the road users in each image; the score was the number of correctly reported items (maximum score of 128). Eye movements were recorded while participants performed the DriveSafe test using a Tobii TX300 eye tracking system. Results There was a significant main effect of blur on DriveSafe scores (best-corrected: 114.9 vs blur: 93.2; p < 0.001). There was also a significant age and blur interaction on the DriveSafe scores (p < 0.001) such that the young drivers were more negatively affected by blur than the older drivers (reductions of 22% and 13% respectively; p < 0.001): with best-corrected vision, the young drivers performed better than the older drivers (DriveSafe scores: 118.4 vs 111.5; p = 0.001), while with blur, the young drivers performed worse than the older drivers (88.6 vs 95.9; p = 0.009). For the eye movement patterns, blur significantly reduced the number of fixations on road users (best-corrected: 5.1 vs blur: 4.5; p < 0.001), fixation duration on road users (2.0 s vs 1.8 s; p < 0.001) and saccade amplitudes (7.4° vs 6.7°; p < 0.001). A main effect of age on eye movements was also found where older drivers made smaller saccades than the young drivers (6.7° vs 7.4°; p < 0.001). Conclusions Blur reduced DriveSafe scores for both age groups and this effect was greater for the young drivers. The decrease in number of fixations and fixation duration on road users, as well as the reduction in saccade amplitudes under the blurred condition, highlight the difficulty experienced in performing the task in the presence of optical blur, which suggests that uncorrected refractive errors may have a detrimental impact on aspects of driving performance.