Perceptual Thresholds for Radial Optic Flow Distortion in Near-Eye Stereoscopic Displays.

We provide the first perceptual quantification of user's sensitivity to radial optic flow artifacts and demonstrate a promising approach for masking this optic flow artifact via blink suppression. Near-eye HMOs allow users to feel immersed in virtual environments by providing visual cues, like motion parallax and stereoscopy, that mimic how we view the physical world. However, these systems exhibit a variety of perceptual artifacts that can limit their usability and the user's sense of presence in VR. One well-known artifact is the vergence-accommodation conflict (VAC). Varifocal displays can mitigate VAC, but bring with them other artifacts such as a change in virtual image size (radial optic flow) when the focal plane changes. We conducted a set of psychophysical studies to measure users' ability to perceive this radial flow artifact before, during, and after self-initiated blinks. Our results showed that visual sensitivity was reduced by a factor of 10 at the start and for ~70 ms after a blink was detected. Pre- and post-blink sensitivity was, on average, ~O.15% image size change during normal viewing and increased to ~1.5- 2.0% during blinks. Our results imply that a rapid (under 70 ms) radial optic flow distortion can go unnoticed during a blink. Furthermore, our results provide empirical data that can be used to inform engineering requirements for both hardware design and software-based graphical correction algorithms for future varifocal near-eye displays. Our project website is available at https://gamma.umd.edu/ROF/.

The sexual politics of technology industry responses to online child sexual exploitation during COVID-19: "This pernicious elitism".

BACKGROUND: Increasing rates of online child sexual exploitation further spiked during the COVID-19 pandemic at a time of disrupted child protection capacity. While the technology industry is central to coordinated efforts to prevent online abuse and remove harmful content, it is largely exempt from formal child protection obligations. OBJECTIVE: The aim of this study was to examine the response of the technology industry to online child sexual exploitation during COVID-19 from the perspective of anti-exploitation professionals. PARTICIPANTS AND SETTING: An international sample of fifteen anti-exploitation professionals were interviewed as part of a larger study on the impacts of COVID-19 on online child sexual exploitation. METHODS: Interviews were coded based on a template analysis with a focus on interactions with the technology sector during COVID-19. RESULTS: Major themes arising from the analysis were 1) the burden of online safety work on victims and services, 2) the lack of prioritisation of online child protection by technology companies during COVID-19 and 3) the complicity of the technology industry with the online sexploitation of children. CONCLUSIONS: The analysis of the views of anti-exploitation professionals highlights the alignment between the economic interests of the technology sector and the sexual interests of online child abusers in the absence of government oversight. A framework of sexual politics highlights the gendered nature this alignment and emphasises the need for regulatory intervention, harm minimisation and the restructuring of the online environment and technology sector in the interests of child safety.

Parental Production of Child Sexual Abuse Material: A Critical Review.

The aim of this review is to summarize the available empirical research on parental production and to explore the discursive positioning of parental perpetrators within scholarship on child sexual abuse material (CSAM). Academic databases were searched using a combination of relevant terms, and the review was expanded as new terms were identified. The review identified 66 scholarly articles, papers, or books that referred to parental production of CSAM published since 1970. To explore how parental offenders have been positioned within this literature over time, the review is presented according to a chronological summary, drawing out key themes and empirical insights. The review showed that parental CSAM production is common, more likely to involve pre-pubescent victims, more severe abuse, female as well as male perpetrators, and produces high-demand illegal content with serious long-term sequelae. However, the review found that the focus of child trafficking and sexual exploitation scholarship on "commercial" and profit-driven abuse has marginalized and obscured parental CSAM production as a serious policy challenge. These findings warrant a reorientation of research, policy, and practice approaches to technology-facilitated child sexual exploitation, as well as a reflection on the resistance of researchers and policymakers to acknowledging the problem of family-based sexual exploitation.

Contralateral neck failure in oral tongue cancer: Outcomes from two centers using predefined treatment criteria.

BACKGROUND: The objective was to determine the incidence of, and factors associated with contralateral neck failure (CNF) in oral tongue squamous cell carcinoma (OTSCC). METHODS: Consecutive patients with OTSCC between 2007 and 2016 were included. The predefined policy of the contralateral neck included neck dissection (ND) where the primary tumor extended/crossed midline or the contralateral neck was involved; and elective nodal irradiation (ENI) where the primary tumor was ≤1 cm from midline/2 cm from tip. RESULTS: This study included 258 patients. ND was ipsilateral 169 (66%) and bilateral 33 (13%). Fifty-five patients (21%) received ENI to the undissected contralateral neck. CNF occurred in 19 patients (7%) and was similar by treatment received. Utilizing this approach, we observed higher rates of CNF with increasing N classification, perineural invasion, extracapsular extension, and depth of invasion ≥6 mm. CONCLUSIONS: Using our institutional policy of treatment to the contralateral neck, a low rate of CNF (≤10%) was observed.

Impact of histological Oral Tongue Cancer margins on locoregional recurrence: A multi-centre retrospective analysis.

OBJECTIVES: To assess the effect of the histological margins (HM) upon locoregional failure (LRF) and overall survival (OS) for oral tongue squamous cell carcinoma (OTSCC). MATERIALS AND METHODS: We undertook a retrospective review of 258 patients, across two institutions, treated for OTSCC between 2007 and 2016. A Cox-proportional hazards model was used to compare the relative hazard ratio of HM to the accepted standard of 5 mm margins for LRF and OS. RESULTS: The median follow up period was 4.8 years. The 5 year OS and freedom from LRF were 69% and 75% respectively. The Cox-proportional hazards model adjusted for age, DOI and LVI showed increasing risk of mortality and LRF with decreasing HM widths of <5 mm. CONCLUSION: HM >5 mm were associated with a risk reduction of both LRF and mortality in OTSCC. This study supports >5 mm HM being the oncologic goal of surgery.

Exploring clinicians' attitudes about using aspirin for risk reduction in people with Lynch Syndrome with no personal diagnosis of colorectal cancer.

Recent research has shown that aspirin reduces the risk of cancers associated with Lynch Syndrome. However, uncertainty exists around the optimal dosage, treatment duration and whether the benefits of aspirin as a risk-reducing medication (RRM) outweigh adverse medication related side-effects. Little is known about clinicians' attitudes, current practice, and perceived barriers to recommending aspirin as a RRM. To explore the attitudes of clinicians who discuss risk management options with patients with Lynch Syndrome towards using aspirin as a RRM. Clinicians were invited through professional organisations to complete an online survey. Topics included their clinical experience with Lynch Syndrome, views and practice of recommending aspirin as a RRM, and knowledge about clinical risk management guidelines for Lynch Syndrome. Comparison of attitudes was made between three professional groups. 181 respondents were included in the analysis: 59 genetics professionals (genetic counsellors and clinical geneticists, medical oncologists with specialist training in familial cancer), 49 gastroenterologists and 73 colorectal surgeons. Most clinicians (76 %) considered aspirin to be an effective RRM and most (72 %) were confident about discussing it. In all professional categories, those who were confident about discussing aspirin with patients perceived it to be an effective RRM (OR = 2.8 [95 % CI = 1.8-4.2], p < 0.001). Eighty percent (47/59) of genetics professionals reported having discussed the use of aspirin with Lynch Syndrome patients compared to 69 % of gastroenterologists and 68 % of colorectal surgeons. Those who considered aspirin as an effective RRM or who felt confident in their knowledge of the aspirin literature were more likely (OR = 10 [95 % CI = 1.5-65], p = 0.010, OR = 6 [95 % CI = 2.2-16], p < 0.001, respectively) to discuss it with their patients than other professionals in the study. Similarly health professionals who felt confident in their knowledge of literature of aspirin/confident in discussing with the patients were more likely (OR = 6 [95 % CI = 2.2-16], p < 0.001) to discuss with their patients. Health professionals who saw more than ten patients with Lynch Syndrome per year were more likely to be confident in their knowledge of the aspirin literature and discussing it with patients (OR = 4.1 [95 % CI = 1.6-10.2], p = 0.003). Explicit recommendations to take aspirin, was reported by 65/83 (78 %) of health professionals. Eighty-seven percent of health professionals reported a need for patient educational materials about aspirin. Continuing training is needed to increase clinicians' confidence in their knowledge of the literature on the use of aspirin as a RRM. Patient education materials may be helpful in improving consistency in patient care and facilitate communication between clinicians and people living with Lynch Syndrome.

Survival Outcomes of Mucosal Melanoma in the Head and Neck: Case Series and Review of Current Treatment Guidelines.

PURPOSE: Malignant mucosal melanoma of the head and neck (MMHN) is an aggressive and rare neoplasm with poor long-term outcomes. The aim of this study is to evaluate the outcomes of patients treated by a single-institution head and neck multidisciplinary team. MATERIALS AND METHODS: In this retrospective case series, all MMHN cases treated at the Royal Melbourne Hospital from 1990-2015 were retrospectively reviewed. Patient demographic characteristics (eg, age), treatment offered, pathology, and outcomes were collected, tabulated, and correlated with outcomes. Survival outcomes were calculated by the Kaplan-Meier method. Comparison was made between oral and sinonasal melanomas. RESULTS: A total of 16 cases were identified. Two were excluded because of inaccessible data. Of the 14 remaining cases, 8 were sinonasal melanomas and 6 were oral cavity melanomas. Sinonasal tumor patients presented with epistaxis or visual impairment. Oral melanoma patients presented with pigmented lesions or ulceration. Follow-up ranged from 4 months to 11 years. In 2 patients, locoregional recurrences developed that were successfully re-excised. Six patients died of distant metastases despite clear surgical margins. Two patients with sinonasal melanomas died of extensive local disease with intracranial invasion. One patient died 4 years after diagnosis without disease. There were no failures in the neck. The 2- and 5-year overall survival rates were 63.3% and 31.7%, respectively, by the Kaplan-Meier method. The difference in survival between oral and sinonasal melanomas was not statistically significant. CONCLUSIONS: Despite clear surgical margins, MMHN has a poor prognosis and most deaths are due to distant metastases. Systemic therapies such as those used in cutaneous melanoma treatment might be used in the future for MMHN.

Hydrothermally generated aromatic compounds are consumed by bacteria colonizing in Atlantis II Deep of the Red Sea.

Hydrothermal ecosystems have a wide distribution on Earth and many can be found in the basin of the Red Sea. Production of aromatic compounds occurs in a temperature window of ∼60-150 °C by utilizing organic debris. In the past 50 years, the temperature of the Atlantis II Deep brine pool in the Red Sea has increased from 56 to 68 °C, whereas the temperature at the nearby Discovery Deep brine pool has remained relatively stable at about 44 °C. In this report, we confirmed the presence of aromatic compounds in the Atlantis II brine pool as expected. The presence of the aromatic compounds might have disturbed the microbes in the Atlantis II. To show shifted microbial communities and their metabolisms, we sequenced the metagenomes of the microbes from both brine pools. Classification based on metareads and the 16S rRNA gene sequences from clones showed a strong divergence of dominant bacterial species between the pools. Bacteria capable of aromatic degradation were present in the Atlantis II brine pool. A comparison of the metabolic pathways showed that several aromatic degradation pathways were significantly enriched in the Atlantis II brine pool, suggesting the presence of aromatic compounds. Pathways utilizing metabolites derived from aromatic degradation were also significantly affected. In the Discovery brine pool, the most abundant genes from the microbes were related to sugar metabolism pathways and DNA synthesis and repair, suggesting a different strategy for the utilization of carbon and energy sources between the Discovery brine pool and the Atlantis II brine pool.

Vertical stratification of microbial communities in the Red Sea revealed by 16S rDNA pyrosequencing.

The ecosystems of the Red Sea are among the least-explored microbial habitats in the marine environment. In this study, we investigated the microbial communities in the water column overlying the Atlantis II Deep and Discovery Deep in the Red Sea. Taxonomic classification of pyrosequencing reads of the 16S rRNA gene amplicons showed vertical stratification of microbial diversity from the surface water to 1500 m below the surface. Significant differences in both bacterial and archaeal diversity were observed in the upper (20 [corrected] and 50 m) and deeper layers (200 and 1500 m). There were no obvious differences in community structure at the same depth for the two sampling stations. The bacterial community in the upper layer was dominated by Cyanobacteria whereas the deeper layer harbored a large proportion of Proteobacteria. Among Archaea, Euryarchaeota, especially Halobacteriales, were dominant in the upper layer but diminished drastically in the deeper layer where Desulfurococcales belonging to Crenarchaeota became the dominant group. The results of our study indicate that the microbial communities sampled in this study are different from those identified in water column in other parts of the world. The depth-wise compositional variation in the microbial communities is attributable to their adaptations to the various environments in the Red Sea.

2D gel-based proteome and phosphoproteome analysis during larval metamorphosis in two major marine biofouling invertebrates.

Larvae of some benthic invertebrates respond (metamorphose or not) to chemical cues within minutes or hours and often without excessive transcription or translation. Although protein phosphorylation is one of the most important molecular switching mechanisms that govern variety of rapid cellular responses in higher organisms, this is the first study to analyze the global protein expression and protein phosphorylation status during larval metamorphosis in two major marine biofouling invertebrates (a bryozoan Bugula neritina and a barnacle Balanus amphitrite). Results indicate that larval proteomic response to metamorphosis (inhibiton or induction) involves substantial change in the phosphorylation status of proteins rather than de novo protein synthesis. An abundantly expressed and an unnamed phosphoprotein that appears to play key regulatory role in larval metamorphosis was identified. When larvae of bryozoan and barnacle were challenged with a metamorphosis (and kinase) inhibitor, the genistein, the number of phosphoproteins in bryozoan were substantially reduced but drastically increased in barnacle. Taken together, this is the first time that the usefulness of employing 2DE-based proteomic and phosphoproteomic approaches was demonstrated for us to understand the molecular mechanisms of larval metamorphosis and to study the mode-of-action of chemical cues in marine organisms.

Analysis of non-quarter-wave grating by a modified Fourier-transform method.

When unity reflectance is approached, the Fourier-transform method of calculating the reflectance spectrum of an optical grating modulated by a slowly varying envelope becomes unacceptably inaccurate. The modified Fourier transform method of Bovard [Appl. Opt. 29, 24 (1990)] can achieve complete accuracy for quarter-wave gratings. We report herein the extension of Bovard's method to non-quarter-wave gratings. We demonstrate the accurate deployment of our simplified modified Fourier-transform method to apodized linear gratings and optically apodized nonlinear gratings.