Sample records for face masks reduce

  1. Improved techniques reduce face mask leak during simulated neonatal resuscitation: study 2.

    PubMed

    Wood, Fiona E; Morley, Colin J; Dawson, Jennifer A; Kamlin, C Omar F; Owen, Louise S; Donath, Susan; Davis, Peter G

    2008-05-01

    Techniques of positioning and holding neonatal face masks vary. Studies have shown that leak at the face mask is common and often substantial irrespective of operator experience. (1) To identify a technique for face mask placement and hold which will minimise mask leak. (2) To investigate the effect of written instruction and demonstration of the identified technique on mask leak for two round face masks. Three experienced neonatologists compared methods of placing and holding face masks to minimise the leak for Fisher & Paykel 60 mm and Laerdal size 0/1 masks. 50 clinical staff gave positive pressure ventilation to a modified manikin designed to measure leak at the face mask. They were provided with written instructions on how to position and hold each mask and then received a demonstration. Face mask leak was measured after each teaching intervention. A technique of positioning and holding the face masks was identified which minimised leak. The mean (SD) mask leaks before instruction, after instruction and after demonstration were 55% (31), 49% (30), 33% (26) for the Laerdal mask and 57% (25), 47% (28), 32% (30) for the Fisher & Paykel mask. There was no significant difference in mask leak between the two masks. Written instruction alone reduced leak by 8.8% (CI 1.4% to 16.2%) for either mask; when combined with a demonstration mask leak was reduced by 24.1% (CI 16.4% to 31.8%). Written instruction and demonstration of the identified optimal technique resulted in significantly reduced face mask leak.

  2. Face mask use by patients in primary care.

    PubMed

    Tischendorf, Jessica S; Temte, Jonathan L

    2012-02-01

    Face masks are recommended for patients with respiratory symptoms to reduce influenza transmission. Little knowledge exists regarding actual utilization and acceptance of face masks in primary care. Compare distribution of face masks to clinic and community trends in respiratory infection (RI) and influenza-like illness (ILI); estimate the annual need for face masks in primary care. Retrospective observational study of practice data from a 31-week period starting in October 2009. Family practice clinic in Madison, Wis. Patients with fever, cough, or other respiratory symptoms as evaluated by reception staff. Age, sex, and weekly counts of individuals receiving a face mask, as well as counts of RI and ILI patients based on ICD-9 coding from 27 statewide clinics. Face mask counts were 80% of RI counts for the clinic and reflected the demographics of the clinic population. Distribution was correlated to prevalence of RI (R = 0.783, P < 0.001) and ILI (R = 0.632, P < 0.001). Annually, 8% of clinic visits were for RI. The high percentage of face mask use among RI patients reflects the feasibility of this intervention to help control influenza transmission in a primary care setting. Using the present data, clinics can estimate the annual need for face masks.

  3. Face Masks and Cough Etiquette Reduce the Cough Aerosol Concentration of Pseudomonas aeruginosa in People with Cystic Fibrosis.

    PubMed

    Wood, Michelle E; Stockwell, Rebecca E; Johnson, Graham R; Ramsay, Kay A; Sherrard, Laura J; Jabbour, Nassib; Ballard, Emma; O'Rourke, Peter; Kidd, Timothy J; Wainwright, Claire E; Knibbs, Luke D; Sly, Peter D; Morawska, Lidia; Bell, Scott C

    2018-02-01

    People with cystic fibrosis (CF) generate Pseudomonas aeruginosa in droplet nuclei during coughing. The use of surgical masks has been recommended in healthcare settings to minimize pathogen transmission between patients with CF. To determine if face masks and cough etiquette reduce viable P. aeruginosa aerosolized during coughing. Twenty-five adults with CF and chronic P. aeruginosa infection were recruited. Participants performed six talking and coughing maneuvers, with or without face masks (surgical and N95) and hand covering the mouth when coughing (cough etiquette) in an aerosol-sampling device. An Andersen Cascade Impactor was used to sample the aerosol at 2 meters from each participant. Quantitative sputum and aerosol bacterial cultures were performed, and participants rated the mask comfort levels during the cough maneuvers. During uncovered coughing (reference maneuver), 19 of 25 (76%) participants produced aerosols containing P. aeruginosa, with a positive correlation found between sputum P. aeruginosa concentration (measured as cfu/ml) and aerosol P. aeruginosa colony-forming units. There was a reduction in aerosol P. aeruginosa load during coughing with a surgical mask, coughing with an N95 mask, and cough etiquette compared with uncovered coughing (P < 0.001). A similar reduction in total colony-forming units was observed for both masks during coughing; yet, participants rated the surgical masks as more comfortable (P = 0.013). Cough etiquette provided approximately half the reduction of viable aerosols of the mask interventions during voluntary coughing. Talking was a low viable aerosol-producing activity. Face masks reduce cough-generated P. aeruginosa aerosols, with the surgical mask providing enhanced comfort. Cough etiquette was less effective at reducing viable aerosols.

  4. Surgical Face Masks Worn by Patients with Multidrug-Resistant Tuberculosis

    PubMed Central

    Mphahlele, Matsie; Stoltz, Anton; Venter, Kobus; Mathebula, Rirhandzu; Masotla, Thabiso; Lubbe, Willem; Pagano, Marcello; First, Melvin; Jensen, Paul A.; van der Walt, Martie; Nardell, Edward A.

    2012-01-01

    Rationale: Drug-resistant tuberculosis transmission in hospitals threatens staff and patient health. Surgical face masks used by patients with tuberculosis (TB) are believed to reduce transmission but have not been rigorously tested. Objectives: We sought to quantify the efficacy of surgical face masks when worn by patients with multidrug-resistant TB (MDR-TB). Methods: Over 3 months, 17 patients with pulmonary MDR-TB occupied an MDR-TB ward in South Africa and wore face masks on alternate days. Ward air was exhausted to two identical chambers, each housing 90 pathogen-free guinea pigs that breathed ward air either when patients wore surgical face masks (intervention group) or when patients did not wear masks (control group). Efficacy was based on differences in guinea pig infections in each chamber. Measurements and Main Results: Sixty-nine of 90 control guinea pigs (76.6%; 95% confidence interval [CI], 68–85%) became infected, compared with 36 of 90 intervention guinea pigs (40%; 95% CI, 31–51%), representing a 56% (95% CI, 33–70.5%) decreased risk of TB transmission when patients used masks. Conclusions: Surgical face masks on patients with MDR-TB significantly reduced transmission and offer an adjunct measure for reducing TB transmission from infectious patients. PMID:22323300

  5. Comparison of face masks in the bag-mask ventilation of a manikin.

    PubMed

    Redfern, D; Rassam, S; Stacey, M R; Mecklenburgh, J S

    2006-02-01

    We conducted a study investigating the effectiveness of four face mask designs in the bag-mask ventilation of a special manikin adapted to simulate a difficult airway. Forty-eight anaesthetists volunteered to bag-mask ventilate the manikin for 3 min with four different face masks. The primary outcome of the study was to calculate mean percentage leak from the face masks over 3 min. Anaesthetists were also asked to rate the face masks using a visual analogue score. The single-use scented intersurgical face mask had the lowest mean leak (20%). This was significantly lower than the mean leak from the single-use, cushioned 7,000 series Air Safety Ltd. face mask (24%) and the reusable silicone Laerdal face mask (27%) but not significantly lower than the mean leak from the reusable anatomical intersurgical face mask (23%). There was a large variation in both performance and satisfaction between anaesthetists with each design. This highlights the importance of having a variety of face masks available for emergency use.

  6. Face mask use and control of respiratory virus transmission in households.

    PubMed

    MacIntyre, C Raina; Cauchemez, Simon; Dwyer, Dominic E; Seale, Holly; Cheung, Pamela; Browne, Gary; Fasher, Michael; Wood, James; Gao, Zhanhai; Booy, Robert; Ferguson, Neil

    2009-02-01

    Many countries are stockpiling face masks for use as a nonpharmaceutical intervention to control virus transmission during an influenza pandemic. We conducted a prospective cluster-randomized trial comparing surgical masks, non-fit-tested P2 masks, and no masks in prevention of influenza-like illness (ILI) in households. Mask use adherence was self-reported. During the 2006 and 2007 winter seasons, 286 exposed adults from 143 households who had been exposed to a child with clinical respiratory illness were recruited. We found that adherence to mask use significantly reduced the risk for ILI-associated infection, but <50% of participants wore masks most of the time. We concluded that household use of face masks is associated with low adherence and is ineffective for controlling seasonal respiratory disease. However, during a severe pandemic when use of face masks might be greater, pandemic transmission in households could be reduced.

  7. Reducing oral flora contamination of intravitreal injections with face mask or silence.

    PubMed

    Doshi, Rishi R; Leng, Theodore; Fung, Anne E

    2012-03-01

    To provide experimental evidence to support or refute the proposition that the use of surgical face masks and/or avoidance of talking can decrease the dispersion of respiratory flora during an intravitreal injection. Ten surgeons recited a 30-second standardized script with blood agar plates positioned 30 cm below their mouths. The plates were divided into 4 groups, with 10 plates per group. In Group 1, participants did not wear a face mask. In Group 2, participants wore a standard surgical mask. In Group 3, no mask was worn, but plates were pretreated with 5% povidone-iodine. In Group 4, no mask was worn, and participants remained silent for 30 seconds. The plates were then incubated at 37°C for 24 hours, and the number of colony-forming units (CFUs) was determined. Mean bacterial growth were as follows: Group 1, 8.6 CFUs per subject; Group 2, 1.1 CFUs per subject; Group 3, 0.1 CFUs per subject; and Group 4, 2.4 CFUs per subject. Differences between the groups were statistically significant (P < 0.05), with the exception of Group 2 versus Group 4 (P = 0.115). The use of a face mask and avoidance of talking each significantly decreased the dispersion of bacteria. Even without these interventions, plates pretreated with povidone-iodine demonstrated the least bacterial growth.

  8. Lightweight Face Mask

    NASA Technical Reports Server (NTRS)

    Cason, W. E. I.; Baucom, R. M.; Evans, R. C.

    1982-01-01

    Lightweight face mask originally developed to protect epileptic patients during seizures could have many other medical and nonmedical applications such as muscular distrophy patients, football linesmen and riot-control police. Masks are extremely lightweight, the lightest of the configurations weighing only 136 grams.

  9. Professional and Home-Made Face Masks Reduce Exposure to Respiratory Infections among the General Population

    PubMed Central

    van der Sande, Marianne; Teunis, Peter; Sabel, Rob

    2008-01-01

    Background Governments are preparing for a potential influenza pandemic. Therefore they need data to assess the possible impact of interventions. Face-masks worn by the general population could be an accessible and affordable intervention, if effective when worn under routine circumstances. Methodology We assessed transmission reduction potential provided by personal respirators, surgical masks and home-made masks when worn during a variety of activities by healthy volunteers and a simulated patient. Principal Findings All types of masks reduced aerosol exposure, relatively stable over time, unaffected by duration of wear or type of activity, but with a high degree of individual variation. Personal respirators were more efficient than surgical masks, which were more efficient than home-made masks. Regardless of mask type, children were less well protected. Outward protection (mask wearing by a mechanical head) was less effective than inward protection (mask wearing by healthy volunteers). Conclusions/Significance Any type of general mask use is likely to decrease viral exposure and infection risk on a population level, in spite of imperfect fit and imperfect adherence, personal respirators providing most protection. Masks worn by patients may not offer as great a degree of protection against aerosol transmission. PMID:18612429

  10. Professional and home-made face masks reduce exposure to respiratory infections among the general population.

    PubMed

    van der Sande, Marianne; Teunis, Peter; Sabel, Rob

    2008-07-09

    Governments are preparing for a potential influenza pandemic. Therefore they need data to assess the possible impact of interventions. Face-masks worn by the general population could be an accessible and affordable intervention, if effective when worn under routine circumstances. We assessed transmission reduction potential provided by personal respirators, surgical masks and home-made masks when worn during a variety of activities by healthy volunteers and a simulated patient. All types of masks reduced aerosol exposure, relatively stable over time, unaffected by duration of wear or type of activity, but with a high degree of individual variation. Personal respirators were more efficient than surgical masks, which were more efficient than home-made masks. Regardless of mask type, children were less well protected. Outward protection (mask wearing by a mechanical head) was less effective than inward protection (mask wearing by healthy volunteers). Any type of general mask use is likely to decrease viral exposure and infection risk on a population level, in spite of imperfect fit and imperfect adherence, personal respirators providing most protection. Masks worn by patients may not offer as great a degree of protection against aerosol transmission.

  11. Nasal mask ventilation is better than face mask ventilation in edentulous patients.

    PubMed

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients.

  12. Emotional intelligence is associated with reduced insula responses to masked angry faces.

    PubMed

    Alkozei, Anna; Killgore, William D S

    2015-07-08

    High levels of emotional intelligence (EI) have been associated with increased success in the workplace, greater quality of personal relationships, and enhanced wellbeing. Evidence suggests that EI is mediated extensively by the interplay of key emotion regions including the amygdala, insula, and ventromedial prefrontal cortex, among others. The insula, in particular, is important for processing interoceptive and somatic cues that are interpreted as emotional responses. We investigated the association between EI and functional brain responses within the aforementioned neurocircuitry in response to subliminal presentations of social threat. Fifty-four healthy adults completed the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) and underwent functional magnetic brain imaging while viewing subliminal presentations of faces displaying anger, using a backward masked facial affect paradigm to minimize conscious awareness of the expressed emotion. In response to masked angry faces, the total MSCEIT scores correlated negatively with a cluster of activation located within the left insula, but not with activation in any other region of interest. Considering the insula's role in the processing of interoceptive emotional cues, the results suggest that greater EI is associated with reduced emotional visceral reactivity and/or more accurate interoceptive prediction when confronted with stimuli indicative of social threat.

  13. Nasal mask ventilation is better than face mask ventilation in edentulous patients

    PubMed Central

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Background and Aims: Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Material and Methods: Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. Results: A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Conclusion: Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients. PMID:27625477

  14. Computerized Dead-Space Volume Measurement of Face Masks Applied to Simulated Faces.

    PubMed

    Amirav, Israel; Luder, Anthony S; Halamish, Asaf; Marzuk, Chatib; Daitzchman, Marcelo; Newhouse, Michael T

    2015-09-01

    The dead-space volume (VD) of face masks for metered-dose inhaler treatments is particularly important in infants and young children with asthma, who have relatively low tidal volumes. Data about VD have been traditionally obtained from water displacement measurements, in which masks are held against a flat surface. Because, in real life, masks are placed against the face, VD is likely to differ considerably between masks depending upon their contour and fit. The aim of this study was to develop an accurate and reliable way to measure VD electronically and to apply this technique by comparing the electronic VD of commonly available face masks. Average digital faces were obtained from 3-dimensional images of 270 infants and children. Commonly used face masks (small and medium) from various manufacturers (Monaghan Medical, Pari Respiratory Equipment, Philips Respironics, and InspiRx) were scanned and digitized by means of computed tomography. Each mask was electronically applied to its respective digital face, and the VD enclosed (mL) was computerized and precisely measured. VD varied between 22.6 mL (SootherMask, InspiRx) and 43.1 mL (Vortex, Pari) for small masks and between 41.7 mL (SootherMask) and 71.5 mL (AeroChamber, Monaghan Medical) for medium masks. These values were significantly lower and less variable than measurements obtained by water displacement. Computerized techniques provide an innovative and relatively simple way of accurately measuring the VD of face masks applied to digital faces. As determined by computerized measurement using average-size virtual faces, the InspiRx masks had a significantly smaller VD for both small and medium masks compared with the other masks. This is of considerable importance with respect to aerosol dose and delivery time, particularly in young children. (ClinicalTrials.gov registration NCT01274299.). Copyright © 2015 by Daedalus Enterprises.

  15. Emergency face-mask removal effectiveness: a comparison of traditional and nontraditional football helmet face-mask attachment systems.

    PubMed

    Swartz, Erik E; Belmore, Keith; Decoster, Laura C; Armstrong, Charles W

    2010-01-01

    Football helmet face-mask attachment design changes might affect the effectiveness of face-mask removal. To compare the efficiency of face-mask removal between newly designed and traditional football helmets. Controlled laboratory study. Applied biomechanics laboratory. Twenty-five certified athletic trainers. The independent variable was face-mask attachment system on 5 levels: (1) Revolution IQ with Quick Release (QR), (2) Revolution IQ with Quick Release hardware altered (QRAlt), (3) traditional (Trad), (4) traditional with hardware altered (TradAlt), and (5) ION 4D (ION). Participants removed face masks using a cordless screwdriver with a back-up cutting tool or only the cutting tool for the ION. Investigators altered face-mask hardware to unexpectedly challenge participants during removal for traditional and Revolution IQ helmets. Participants completed each condition twice in random order and were blinded to hardware alteration. Removal success, removal time, helmet motion, and rating of perceived exertion (RPE). Time and 3-dimensional helmet motion were recorded. If the face mask remained attached at 3 minutes, the trial was categorized as unsuccessful. Participants rated each trial for level of difficulty (RPE). We used repeated-measures analyses of variance (α  =  .05) with follow-up comparisons to test for differences. Removal success was 100% (48 of 48) for QR, Trad, and ION; 97.9% (47 of 48) for TradAlt; and 72.9% (35 of 48) for QRAlt. Differences in time for face-mask removal were detected (F(4,20)  =  48.87, P  =  .001), with times ranging from 33.96 ± 14.14 seconds for QR to 99.22 ± 20.53 seconds for QRAlt. Differences were found in range of motion during face-mask removal (F(4,20)  =  16.25, P  =  .001), with range of motion from 10.10° ± 3.07° for QR to 16.91° ± 5.36° for TradAlt. Differences also were detected in RPE during face-mask removal (F(4,20)  =  43.20, P  =  .001), with participants reporting average

  16. Emergency Face-Mask Removal Effectiveness: A Comparison of Traditional and Nontraditional Football Helmet Face-Mask Attachment Systems

    PubMed Central

    Swartz, Erik E.; Belmore, Keith; Decoster, Laura C.; Armstrong, Charles W.

    2010-01-01

    Abstract Context: Football helmet face-mask attachment design changes might affect the effectiveness of face-mask removal. Objective: To compare the efficiency of face-mask removal between newly designed and traditional football helmets. Design: Controlled laboratory study. Setting: Applied biomechanics laboratory. Participants: Twenty-five certified athletic trainers. Intervention(s): The independent variable was face-mask attachment system on 5 levels: (1) Revolution IQ with Quick Release (QR), (2) Revolution IQ with Quick Release hardware altered (QRAlt), (3) traditional (Trad), (4) traditional with hardware altered (TradAlt), and (5) ION 4D (ION). Participants removed face masks using a cordless screwdriver with a back-up cutting tool or only the cutting tool for the ION. Investigators altered face-mask hardware to unexpectedly challenge participants during removal for traditional and Revolution IQ helmets. Participants completed each condition twice in random order and were blinded to hardware alteration. Main Outcome Measure(s): Removal success, removal time, helmet motion, and rating of perceived exertion (RPE). Time and 3-dimensional helmet motion were recorded. If the face mask remained attached at 3 minutes, the trial was categorized as unsuccessful. Participants rated each trial for level of difficulty (RPE). We used repeated-measures analyses of variance (α  =  .05) with follow-up comparisons to test for differences. Results: Removal success was 100% (48 of 48) for QR, Trad, and ION; 97.9% (47 of 48) for TradAlt; and 72.9% (35 of 48) for QRAlt. Differences in time for face-mask removal were detected (F4,20  =  48.87, P  =  .001), with times ranging from 33.96 ± 14.14 seconds for QR to 99.22 ± 20.53 seconds for QRAlt. Differences were found in range of motion during face-mask removal (F4,20  =  16.25, P  =  .001), with range of motion from 10.10° ± 3.07° for QR to 16.91° ± 5.36° for TradAlt. Differences also were detected

  17. A novel anti-influenza copper oxide containing respiratory face mask.

    PubMed

    Borkow, Gadi; Zhou, Steve S; Page, Tom; Gabbay, Jeffrey

    2010-06-25

    Protective respiratory face masks protect the nose and mouth of the wearer from vapor drops carrying viruses or other infectious pathogens. However, incorrect use and disposal may actually increase the risk of pathogen transmission, rather than reduce it, especially when masks are used by non-professionals such as the lay public. Copper oxide displays potent antiviral properties. A platform technology has been developed that permanently introduces copper oxide into polymeric materials, conferring them with potent biocidal properties. We demonstrate that impregnation of copper oxide into respiratory protective face masks endows them with potent biocidal properties in addition to their inherent filtration properties. Both control and copper oxide impregnated masks filtered above 99.85% of aerosolized viruses when challenged with 5.66+/-0.51 and 6.17+/-0.37 log(10)TCID(50) of human influenza A virus (H1N1) and avian influenza virus (H9N2), respectively, under simulated breathing conditions (28.3 L/min). Importantly, no infectious human influenza A viral titers were recovered from the copper oxide containing masks within 30 minutes (< or = 0.88 log(10)TCID(50)), while 4.67+/-1.35 log(10)TCID(50) were recovered from the control masks. Similarly, the infectious avian influenza titers recovered from the copper oxide containing masks were < or = 0.97+/-0.01 log(10)TCID(50) and from the control masks 5.03+/-0.54 log(10)TCID(50). The copper oxide containing masks successfully passed Bacterial Filtration Efficacy, Differential Pressure, Latex Particle Challenge, and Resistance to Penetration by Synthetic Blood tests designed to test the filtration properties of face masks in accordance with the European EN 14683:2005 and NIOSH N95 standards. Impregnation of copper oxide into respiratory protective face masks endows them with potent anti-influenza biocidal properties without altering their physical barrier properties. The use of biocidal masks may significantly reduce the risk

  18. A Novel Anti-Influenza Copper Oxide Containing Respiratory Face Mask

    PubMed Central

    Borkow, Gadi; Zhou, Steve S.; Page, Tom; Gabbay, Jeffrey

    2010-01-01

    Background Protective respiratory face masks protect the nose and mouth of the wearer from vapor drops carrying viruses or other infectious pathogens. However, incorrect use and disposal may actually increase the risk of pathogen transmission, rather than reduce it, especially when masks are used by non-professionals such as the lay public. Copper oxide displays potent antiviral properties. A platform technology has been developed that permanently introduces copper oxide into polymeric materials, conferring them with potent biocidal properties. Methodology/Principal Findings We demonstrate that impregnation of copper oxide into respiratory protective face masks endows them with potent biocidal properties in addition to their inherent filtration properties. Both control and copper oxide impregnated masks filtered above 99.85% of aerosolized viruses when challenged with 5.66±0.51 and 6.17±0.37 log10TCID50 of human influenza A virus (H1N1) and avian influenza virus (H9N2), respectively, under simulated breathing conditions (28.3 L/min). Importantly, no infectious human influenza A viral titers were recovered from the copper oxide containing masks within 30 minutes (≤0.88 log10TCID50), while 4.67±1.35 log10TCID50 were recovered from the control masks. Similarly, the infectious avian influenza titers recovered from the copper oxide containing masks were ≤0.97±0.01 log10TCID50 and from the control masks 5.03±0.54 log10TCID50. The copper oxide containing masks successfully passed Bacterial Filtration Efficacy, Differential Pressure, Latex Particle Challenge, and Resistance to Penetration by Synthetic Blood tests designed to test the filtration properties of face masks in accordance with the European EN 14683:2005 and NIOSH N95 standards. Conclusions/Significance Impregnation of copper oxide into respiratory protective face masks endows them with potent anti-influenza biocidal properties without altering their physical barrier properties. The use of biocidal masks

  19. A face versus non-face context influences amygdala responses to masked fearful eye whites.

    PubMed

    Kim, M Justin; Solomon, Kimberly M; Neta, Maital; Davis, F Caroline; Oler, Jonathan A; Mazzulla, Emily C; Whalen, Paul J

    2016-12-01

    The structure of the mask stimulus is crucial in backward masking studies and we recently demonstrated such an effect when masking faces. Specifically, we showed that activity of the amygdala is increased to fearful facial expressions masked with neutral faces and decreased to fearful expressions masked with a pattern mask-but critically both masked conditions discriminated fearful expressions from happy expressions. Given this finding, we sought to test whether masked fearful eye whites would produce a similar profile of amygdala response in a face vs non-face context. During functional magnetic resonance imaging scanning sessions, 30 participants viewed fearful or happy eye whites masked with either neutral faces or pattern images. Results indicated amygdala activity was increased to fearful vs happy eye whites in the face mask condition, but decreased to fearful vs happy eye whites in the pattern mask condition-effectively replicating and expanding our previous report. Our data support the idea that the amygdala is responsive to fearful eye whites, but that the nature of this activity observed in a backward masking design depends on the mask stimulus. © The Author (2016). Published by Oxford University Press.

  20. Supreme Laryngeal Mask Airway versus Face Mask during Neonatal Resuscitation: A Randomized Controlled Trial.

    PubMed

    Trevisanuto, Daniele; Cavallin, Francesco; Nguyen, Loi Ngoc; Nguyen, Tien Viet; Tran, Linh Dieu; Tran, Chien Dinh; Doglioni, Nicoletta; Micaglio, Massimo; Moccia, Luciano

    2015-08-01

    To assess the effectiveness of supreme laryngeal mask airway (SLMA) over face mask ventilation for preventing need for endotracheal intubation at birth. We report a prospective, randomized, parallel 1:1, unblinded, controlled trial. After a short-term educational intervention on SLMA use, infants ≥34-week gestation and/or expected birth weight ≥1500 g requiring positive pressure ventilation (PPV) at birth were randomized to resuscitation by SLMA or face mask. The primary outcome was the success rate of the resuscitation devices (SLMA or face mask) defined as the achievement of an effective PPV preventing the need for endotracheal intubation. We enrolled 142 patients (71 in SLMA and 71 in face mask group, respectively). Successful resuscitation rate was significantly higher with the SLMA compared with face mask ventilation (91.5% vs 78.9%; P = .03). Apgar score at 5 minutes was significantly higher in SLMA than in face mask group (P = .02). Neonatal intensive care unit admission rate was significantly lower in SLMA than in face mask group (P = .02). No complications related to the procedure occurred. In newborns with gestational age ≥34 weeks and/or expected birth weight ≥1500 g needing PPV at birth, the SLMA is more effective than face mask to prevent endotracheal intubation. The SLMA is effective in clinical practice after a short-term educational intervention. Registered with ClinicalTrials.gov: NCT01963936. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Face mask ventilation in edentulous patients: a comparison of mandibular groove and lower lip placement.

    PubMed

    Racine, Stéphane X; Solis, Audrey; Hamou, Nora Ait; Letoumelin, Philippe; Hepner, David L; Beloucif, Sadek; Baillard, Christophe

    2010-05-01

    In edentulous patients, it may be difficult to perform face mask ventilation because of inadequate seal with air leaks. Our aim was to ascertain whether the "lower lip" face mask placement, as a new face mask ventilation method, is more effective at reducing air leaks than the standard face mask placement. Forty-nine edentulous patients with inadequate seal and air leak during two-hand positive-pressure ventilation using the ventilator circle system were prospectively evaluated. In the presence of air leaks, defined as a difference of at least 33% between inspired and expired tidal volumes, the mask was placed in a lower lip position by repositioning the caudal end of the mask above the lower lip while maintaining the head in extension. The results are expressed as mean +/- SD or median (25th-75th percentiles). Patient characteristics included age (71 +/- 11 yr) and body mass index (24 +/- 4 kg/m2). By using the standard method, the median inspired and expired tidal volumes were 450 ml (400-500 ml) and 0 ml (0-50 ml), respectively, and the median air leak was 400 ml (365-485 ml). After placing the mask in the lower lip position, the median expired tidal volume increased to 400 ml (380-490), and the median air leak decreased to 10 ml (0-20 ml) (P < 0.001 vs. standard method). The lower lip face mask placement with two hands reduced the air leak by 95% (80-100%). In edentulous patients with inadequate face mask ventilation, the lower lip face mask placement with two hands markedly reduced the air leak and improved ventilation.

  2. A new suction mask to reduce leak during neonatal resuscitation: a manikin study.

    PubMed

    Lorenz, Laila; Maxfield, Dominic A; Dawson, Jennifer A; Kamlin, C Omar F; McGrory, Lorraine; Thio, Marta; Donath, Susan M; Davis, Peter G

    2016-09-01

    Leak around the face mask is a common problem during neonatal resuscitation. A newly designed face mask using a suction system to enhance contact between the mask and the infant's face might reduce leak and improve neonatal resuscitation. The aim of the study is to determine whether leak is reduced using the suction mask (Resusi-sure mask) compared with a conventional mask (Laerdal Silicone mask) in a manikin model. Sixty participants from different professional categories (neonatal consultants, fellows, registrars, nurses, midwives and students) used each face mask in a random order to deliver 2 min of positive pressure ventilation to a manikin. Delivered airway pressures were measured using a pressure line. Inspiratory and expiratory flows were measured using a flow sensor, and expiratory tidal volumes and mask leaks were derived from these values. A median (IQR) leak of 12.1 (0.6-39.0)% was found with the conventional mask compared with 0.7 (0.2-4.6)% using the suction mask (p=0.002). 50% of the participants preferred to use the suction mask and 38% preferred to use the conventional mask. There was no correlation between leak and operator experience. A new neonatal face mask based on the suction system reduced leak in a manikin model. Clinical studies to test the safety and effectiveness of this mask are needed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  3. Protective Face Mask

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Mask to protect the physically impaired from injuries to the face and head has been developed by Langley Research Center. It is made of composite materials, usually graphite or boron fibers woven into a matrix. Weighs less than three ounces.

  4. Design of aerosol face masks for children using computerized 3D face analysis.

    PubMed

    Amirav, Israel; Luder, Anthony S; Halamish, Asaf; Raviv, Dan; Kimmel, Ron; Waisman, Dan; Newhouse, Michael T

    2014-08-01

    Aerosol masks were originally developed for adults and downsized for children. Overall fit to minimize dead space and a tight seal are problematic, because children's faces undergo rapid and marked topographic and internal anthropometric changes in their first few months/years of life. Facial three-dimensional (3D) anthropometric data were used to design an optimized pediatric mask. Children's faces (n=271, aged 1 month to 4 years) were scanned with 3D technology. Data for the distance from the bridge of the nose to the tip of the chin (H) and the width of the mouth opening (W) were used to categorize the scans into "small," "medium," and "large" "clusters." "Average" masks were developed from each cluster to provide an optimal seal with minimal dead space. The resulting computerized contour, W and H, were used to develop the SootherMask® that enables children, "suckling" on their own pacifier, to keep the mask on their face, mainly by means of subatmospheric pressure. The relatively wide and flexible rim of the mask accommodates variations in facial size within and between clusters. Unique pediatric face masks were developed based on anthropometric data obtained through computerized 3D face analysis. These masks follow facial contours and gently seal to the child's face, and thus may minimize aerosol leakage and dead space.

  5. [Oxygenation: the impact of face mask coupling.].

    PubMed

    Gregori, Waldemar Montoya de; Mathias, Lígia Andrade da Silva Telles; Piccinini Filho, Luiz; Pena, Ernesto Leonardo de Carpio; Vicuna, Aníbal Heberto Mora; Vieira, Joaquim Edson

    2005-10-01

    Different oxygenation techniques aim at promoting denitrogenation before apnea during induction. The main reason why CIO2 = 100% cannot be reached is the lack of adequate face mask coupling, allowing the entry of room air. Although anesthesiologists know this principle, not all of them apply it correctly, facilitating the entry of air in fresh gases flow and consequently diluting CIO2. This prospective study was performed to comparatively evaluate, through the variation of oxygen expired concentration (CEO2), the efficacy of the oxygenation technique via face mask in the conditions routinely used by anesthesiologists, simulating situations of progressive leaks. Oxygen end-tidal concentrations of 15 volunteers, physical status ASA I, were studied with 8 deep breaths (vital capacity) in 60 s with fresh gas flow of 10 L.min-1. The face mask was: tightly fitted with 100% CIO2 (Tf100) or varying from 50% to 90%, (Tf50, Tf60, Tf70, Tf80, Tf90); gravity-coupled to face and 100% CIO2 (Grav) and moved 1 cm away from face with 100% CIO2 (Aw). CEO2 was recorded at 10 s intervals. P < 0.05 was considered statistically significant. CEO2 has increased for all groups (p < 0.001), but only Tf100 reached values close to ideal (82.20 - 87). Comparing mean CEO2 of Grav and Tf100 at the end of 60s, (82.20 and 65.87) there was a difference of approximately 20% between both techniques, since gravity-coupled mask only did not provide adequate oxygenation. There were no significant differences between groups Tf70 and Grav (65.87 and 62.67) in all studied moments, suggesting that the latter simulates a 70% CIO2 at 60 s. Mean Aw group CEO2 increased to 47.20 at 60s showing that this technique may be associated to unacceptable risk of hypoxemia. All situations of face mask coupling gradually increased CEO2, although with decreased oxygenation efficacy due to situations of face mask malposition. This study has shown the need for attention during oxygenation, using well coupled face mask and

  6. Face mask ventilation--the dos and don'ts.

    PubMed

    Wood, Fiona E; Morley, Colin J

    2013-12-01

    Face mask ventilation provides respiratory support to newly born or sick infants. It is a challenging technique and difficult to ensure that an appropriate tidal volume is delivered because large and variable leaks occur between the mask and face; airway obstruction may also occur. Technique is more important than the mask shape although the size must appropriately fit the face. The essence of the technique is to roll the mask on to the face from the chin while avoiding the eyes, with a finger and thumb apply a strong even downward pressure to the top of the mask, away from the stem and sloped sides or skirt of the mask, place the other fingers under the jaw and apply a similar upward pressure. Preterm infants require continuous end-expiratory pressure to facilitate lung aeration and maintain lung volume. This is best done with a T-piece device, not a self-inflating or flow-inflating bag. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Inadequate face mask ventilation--clinical applications.

    PubMed

    Goranović, Tatjana; Milić, Morena; Holjevac, Jadranka Katancić; Maldini, Branka; Sakić, Katarina

    2010-09-01

    Face mask ventilation is a life saving technique. This article will review aetiology and patophysiological consequences of inadequate mask ventilation. The main focus will be on circulatory changes during induction of anesthesia, before and in a short period after intubation that could be attributed to inadequate mask ventilation in humans.

  8. Facial and ocular deposition of nebulized budesonide: effects of face mask design.

    PubMed

    Harris, Keith W; Smaldone, Gerald C

    2008-02-01

    In vivo case reports and in vitro studies have indicated that aerosol therapy using face masks can result in drug deposition on the face and in the eyes, and that face mask design may affect drug delivery. To test different mask/nebulizer combinations for budesonide, a nebulized steroid used to treat pediatric patients with asthma. Using high-performance liquid chromatography, drug delivery (inhaled mass), facial, and ocular deposition of budesonide aerosols were studied in vitro using a ventilated face facsimile (tidal volume, 50 mL; rate, 25 breaths/min, duty cycle 0.4), a tight-fitting test mask, a standard commercial mask, and a prototype mask designed to optimize delivery by reducing particle inertia. Nebulizer insertion into the mask (front loaded vs bottom loaded) was also tested. Particle size was measured by cascade impaction. Pari LC Plus (PARI Respiratory Equipment; Midlothian, VA) and MistyNeb (Allegiance; McGaw Park, IL) nebulizers were tested. Inhaled mass for tight-fitting and prototype masks was similar (13.2 +/- 1.85% vs 14.4 +/- 0.67% [percentage of nebulizer charge], p = 0.58) and significantly greater than for the commercial mask (3.03 +/- 0.26%, p = 0.005). Mask insertion of nebulizer was a key factor (inhaled mass: front loaded vs bottom loaded, 8.23 +/- 0.18% vs 3.03 +/- 0.26%; p = 0.005). Ocular deposition varied by an order of magnitude and was a strong function of mask design (4.77 +/- 0.24% vs 0.35 +/- 0.05%, p = 0.002, tight fitting vs prototype). Particle sizes (7.3 to 9 microm) were larger than previously reported for budesonide. For pediatric breathing patterns, mask design is a key factor defining budesonide delivery to the lungs, face, and eyes. Front-loaded nebulizer mask combinations are more efficient than bottom-loaded systems.

  9. Rescue therapy by switching to total face mask after failure of face mask-delivered noninvasive ventilation in do-not-intubate patients in acute respiratory failure.

    PubMed

    Lemyze, Malcolm; Mallat, Jihad; Nigeon, Olivier; Barrailler, Stéphanie; Pepy, Florent; Gasan, Gaëlle; Vangrunderbeeck, Nicolas; Grosset, Philippe; Tronchon, Laurent; Thevenin, Didier

    2013-02-01

    To evaluate the impact of switching to total face mask in cases where face mask-delivered noninvasive mechanical ventilation has already failed in do-not-intubate patients in acute respiratory failure. Prospective observational study in an ICU and a respiratory stepdown unit over a 12-month study period. Switching to total face mask, which covers the entire face, when noninvasive mechanical ventilation using facial mask (oronasal mask) failed to reverse acute respiratory failure. Seventy-four patients with a do-not-intubate order and treated by noninvasive mechanical ventilation for acute respiratory failure. Failure of face mask-delivered noninvasive mechanical ventilation was associated with a three-fold increase in in-hospital mortality (36% vs. 10.5%; p = 0.009). Nevertheless, 23 out of 36 patients (64%) in whom face mask-delivered noninvasive mechanical ventilation failed to reverse acute respiratory failure and, therefore, switched to total face mask survived hospital discharge. Reasons for switching from facial mask to total face mask included refractory hypercapnic acute respiratory failure (n = 24, 66.7%), painful skin breakdown or facial mask intolerance (n = 11, 30%), and refractory hypoxemia (n = 1, 2.7%). In the 24 patients switched from facial mask to total face mask because of refractory hypercapnia, encephalopathy score (3 [3-4] vs. 2 [2-3]; p < 0.0001), PaCO2 (87 ± 25 mm Hg vs. 70 ± 17 mm Hg; p < 0.0001), and pH (7.24 ± 0.1 vs. 7.32 ± 0.09; p < 0.0001) significantly improved after 2 hrs of total face mask-delivered noninvasive ventilation. Patients switched early to total face mask (in the first 12 hrs) developed less pressure sores (n = 5, 24% vs. n = 13, 87%; p = 0.0002), despite greater length of noninvasive mechanical ventilation within the first 48 hrs (44 hrs vs. 34 hrs; p = 0.05) and less protective dressings (n = 2, 9.5% vs. n = 8, 53.3%; p = 0.007). The optimal cutoff value for face mask-delivered noninvasive mechanical ventilation

  10. Mask ventilation with two different face masks in the delivery room for preterm infants: a randomized controlled trial.

    PubMed

    Cheung, D; Mian, Q; Cheung, P-Y; O'Reilly, M; Aziz, K; van Os, S; Pichler, G; Schmölzer, G M

    2015-07-01

    If an infant fails to initiate spontaneous breathing after birth, international guidelines recommend a positive pressure ventilation (PPV). However, PPV by face mask is frequently inadequate because of leak between the face and mask. Despite a variety of available face masks, none have been prospectively compared in a randomized fashion. We aimed to evaluate and compare leak between two commercially available round face masks (Fisher & Paykel (F&P) and Laerdal) in preterm infants <33 weeks gestational age in the delivery room. Infants born at the Royal Alexandra Hospital from April to September 2013 at <33 weeks gestational age who received mask PPV in the delivery room routinely had a flow sensor placed between the mask and T-piece resuscitator. Infants were randomly assigned to receive PPV with either a F&P or Laerdal face mask. All resuscitators were trained in the use of both face masks. We compared mask leak, airway pressures, tidal volume and ventilation rate between the two groups. Fifty-six preterm infants (n=28 in each group) were enrolled; mean±s.d. gestational age 28±3 weeks; birth weight 1210±448 g; and 30 (52%) were male. Apgar scores at 1 and 5 min were 5±3 and 7±2, respectively. Infants randomized to the F&P face mask and Laerdal face mask had similar mask leak (30 (25-38) versus 35 (24-46)%, median (interquartile range), respectively, P=0.40) and tidal volume (7.1 (4.9-8.9) versus 6.6 (5.2-8.9) ml kg(-1), P=0.69) during PPV. There were no significant differences in ventilation rate, inflation time or airway pressures between groups. The use of either face mask during PPV in the delivery room yields similar mask leak in preterm infants <33 weeks gestational age.

  11. Thermal Management in Nanofiber-Based Face Mask.

    PubMed

    Yang, Ankun; Cai, Lili; Zhang, Rufan; Wang, Jiangyan; Hsu, Po-Chun; Wang, Hongxia; Zhou, Guangmin; Xu, Jinwei; Cui, Yi

    2017-06-14

    Face masks are widely used to filter airborne pollutants, especially when particulate matter (PM) pollution has become a serious concern to public health. Here, the concept of thermal management is introduced into face masks for the first time to enhance the thermal comfort of the user. A system of nanofiber on nanoporous polyethylene (fiber/nanoPE) is developed where the nanofibers with strong PM adhesion ensure high PM capture efficiency (99.6% for PM 2.5 ) with low pressure drop and the nanoPE substrate with high-infrared (IR) transparency (92.1%, weighted based on human body radiation) results in effective radiative cooling. We further demonstrate that by coating nanoPE with a layer of Ag, the fiber/Ag/nanoPE mask shows a high IR reflectance (87.0%) and can be used for warming purposes. These multifunctional face mask designs can be explored for both outdoor and indoor applications to protect people from PM pollutants and simultaneously achieve personal thermal comfort.

  12. A survey of Alberta physicians' use of and attitudes toward face masks and face shields in the operating room setting.

    PubMed

    Davis, Philip J; Spady, Donald; Forgie, Sarah E D

    2007-09-01

    There is little evidence that surgical mask use by physicians in the operating room (OR) reduces surgical site infections (SSIs), but masks do protect the wearer from potentially infectious splashes. Face shields offer even more protection because they cover the eyes, but they may be perceived as offering less protection to the patient than do masks. The objectives of this study were to ascertain if there were predictors to determine which OR physicians are continuing to use masks and what their reasons are for doing so, and which OR physicians would accept face shields and their reasons for doing so. We surveyed the province of Alberta's surgeons, general practice (GP) surgeons, anesthesiologists, and GP anesthetists to determine how many physicians in the OR wear surgical masks, their reasons for wearing surgical masks (ethical, legal, protection of the patient, protection of the wearer), and if they believe that face shields offer more protection to the patient or to the wearer. We also sought to examine which demographic factors affected their responses. The data were examined with chi(2) analysis to assess the relationships of age and practitioner type, and for various outcome variables. A significance level of P < .05 was accepted as statistically significant. The sex of the physician did not affect his/her responses. Older physicians believe that the OR team has an ethical and legal responsibility to wear surgical masks; masks are worn to prevent the spread of disease, not because it is tradition to do so; masks protect the wearer more than do face shields; and wearing face shields alone will subject the patient to higher rates of SSIs. Surgeons are more likely than are anesthesiologists to wear surgical masks in the OR and wear a surgical mask and a face shield if the patient has risk factors for a blood borne infection. According to our survey, age and profession were the most important variables that affected the potential use of surgical masks and face

  13. Disposable surgical face masks for preventing surgical wound infection in clean surgery.

    PubMed

    Vincent, Marina; Edwards, Peggy

    2016-04-26

    Surgical face masks were originally developed to contain and filter droplets containing microorganisms expelled from the mouth and nasopharynx of healthcare workers during surgery, thereby providing protection for the patient. However, there are several ways in which surgical face masks could potentially contribute to contamination of the surgical wound, e.g. by incorrect wear or by leaking air from the side of the mask due to poor string tension. To determine whether the wearing of disposable surgical face masks by the surgical team during clean surgery reduces postoperative surgical wound infection. In December 2015, for this seventh update, we searched: The Cochrane Wounds Specialised Register; The Cochrane Central Register of Controlled Trials; Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE and EBSCO CINAHL. We also searched the bibliographies of all retrieved and relevant publications. There were no restrictions with respect to language, date of publication or study setting. Randomised controlled trials (RCTs) and quasi-randomised controlled trials comparing the use of disposable surgical masks with the use of no mask. Two review authors extracted data independently. We included three trials, involving a total of 2106 participants. There was no statistically significant difference in infection rates between the masked and unmasked group in any of the trials. We identified no new trials for this latest update. From the limited results it is unclear whether the wearing of surgical face masks by members of the surgical team has any impact on surgical wound infection rates for patients undergoing clean surgery.

  14. Increased dead space in face mask continuous positive airway pressure in neonates.

    PubMed

    Hishikawa, Kenji; Fujinaga, Hideshi; Ito, Yushi

    2017-01-01

    Continuous positive airway pressure (CPAP) by face mask is commonly performed in newborn resuscitation. We evaluated the effect of face mask CPAP on system dead space. Face mask CPAP increases dead space. A CPAP model study. We estimated the volume of the inner space of the mask. We devised a face mask CPAP model, in which the outlet of the mask was covered with plastic; and three modified face mask CPAP models, in which holes were drilled near to the cushion of the covered face mask to alter the air exit. We passed a continuous flow of 21% oxygen through each model and we controlled the inner pressure to 5 cmH 2 O by adjusting the flow-relief valve. To evaluate the ventilation in the inner space of each model, we measured the oxygen concentration rise time, that is, the time needed for the oxygen concentration of each model to reach 35% after the oxygen concentration of the continuous flow was raised from 21% to 40%. The volume of inner space of the face mask was 38.3 ml. Oxygen concentration rise time in the face mask CPAP model was significantly longer at various continuous flow rates and points of the inner space of the face mask compared with that of the modified face mask CPAP model. Our study indicates that face mask CPAP leads to an increase in dead space and a decrease in ventilation efficiency under certain circumstances. Pediatr Pulmonol. 2017;52:107-111. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Surgical face masks worn by patients with multidrug-resistant tuberculosis: impact on infectivity of air on a hospital ward.

    PubMed

    Dharmadhikari, Ashwin S; Mphahlele, Matsie; Stoltz, Anton; Venter, Kobus; Mathebula, Rirhandzu; Masotla, Thabiso; Lubbe, Willem; Pagano, Marcello; First, Melvin; Jensen, Paul A; van der Walt, Martie; Nardell, Edward A

    2012-05-15

    Drug-resistant tuberculosis transmission in hospitals threatens staff and patient health. Surgical face masks used by patients with tuberculosis (TB) are believed to reduce transmission but have not been rigorously tested. We sought to quantify the efficacy of surgical face masks when worn by patients with multidrug-resistant TB (MDR-TB). Over 3 months, 17 patients with pulmonary MDR-TB occupied an MDR-TB ward in South Africa and wore face masks on alternate days. Ward air was exhausted to two identical chambers, each housing 90 pathogen-free guinea pigs that breathed ward air either when patients wore surgical face masks (intervention group) or when patients did not wear masks (control group). Efficacy was based on differences in guinea pig infections in each chamber. Sixty-nine of 90 control guinea pigs (76.6%; 95% confidence interval [CI], 68-85%) became infected, compared with 36 of 90 intervention guinea pigs (40%; 95% CI, 31-51%), representing a 56% (95% CI, 33-70.5%) decreased risk of TB transmission when patients used masks. Surgical face masks on patients with MDR-TB significantly reduced transmission and offer an adjunct measure for reducing TB transmission from infectious patients.

  16. Migration from full-head mask to "open-face" mask for immobilization of patients with head and neck cancer.

    PubMed

    Li, Guang; Lovelock, D Michael; Mechalakos, James; Rao, Shyam; Della-Biancia, Cesar; Amols, Howard; Lee, Nancy

    2013-09-06

    To provide an alternative device for immobilization of the head while easing claustrophobia and improving comfort, an "open-face" thermoplastic mask was evaluated using video-based optical surface imaging (OSI) and kilovoltage (kV) X-ray radiography. A three-point thermoplastic head mask with a precut opening and reinforced strips was developed. After molding, it provided sufficient visible facial area as the region of interest for OSI. Using real-time OSI, the head motion of ten volunteers in the new mask was evaluated during mask locking and 15minutes lying on the treatment couch. Using a nose mark with reference to room lasers, forced head movement in open-face and full-head masks (with a nose hole) was compared. Five patients with claustrophobia were immobilized with open-face masks, set up using OSI and kV, and treated in 121 fractions, in which 61 fractions were monitored during treatment using real-time OSI. With the open-face mask, head motion was found to be 1.0 ± 0.6 mm and 0.4° ± 0.2° in volunteers during the experiment, and 0.8 ± 0.3 mm and 0.4° ± 0.2° in patients during treatment. These agree with patient motion calculated from pre-/post-treatment OSI and kV data using different anatomical landmarks. In volunteers, the head shift induced by mask-locking was 2.3 ± 1.7 mm and 1.8° ± 0.6°, and the range of forced movements in the open-face and full-head masks were found to be similar. Most (80%) of the volunteers preferred the open-face mask to the full-head mask, while claustrophobic patients could only tolerate the open-face mask. The open-face mask is characterized for its immobilization capability and can immobilize patients sufficiently (< 2 mm) during radiotherapy. It provides a clinical solution to the immobilization of patients with head and neck (HN) cancer undergoing radiotherapy, and is particularly beneficial for claustrophobic patients. This new open-face mask is readily adopted in radiotherapy clinic as a superior alternative

  17. Thermal Management in Nanofiber-Based Face Mask

    DOE PAGES

    Yang, Ankun; Cai, Lili; Zhang, Rufan; ...

    2017-05-15

    Face masks are widely used to filter airborne pollutants, especially when particulate matter (PM) pollution has become a serious concern to public health. Here in this paper, the concept of thermal management is introduced into face masks for the first time to enhance the thermal comfort of the user. A system of nanofiber on nanoporous polyethylene (fiber/nanoPE) is developed where the nanofibers with strong PM adhesion ensure high PM capture efficiency (99.6% for PM 2.5) with low pressure drop and the nanoPE substrate with high-infrared (IR) transparency (92.1%, weighted based on human body radiation) results in effective radiative cooling. Wemore » further demonstrate that by coating nanoPE with a layer of Ag, the fiber/Ag/nanoPE mask shows a high IR reflectance (87.0%) and can be used for warming purposes. These multifunctional face mask designs can be explored for both outdoor and indoor applications to protect people from PM pollutants and simultaneously achieve personal thermal comfort.« less

  18. Thermal Management in Nanofiber-Based Face Mask

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Ankun; Cai, Lili; Zhang, Rufan

    Face masks are widely used to filter airborne pollutants, especially when particulate matter (PM) pollution has become a serious concern to public health. Here in this paper, the concept of thermal management is introduced into face masks for the first time to enhance the thermal comfort of the user. A system of nanofiber on nanoporous polyethylene (fiber/nanoPE) is developed where the nanofibers with strong PM adhesion ensure high PM capture efficiency (99.6% for PM 2.5) with low pressure drop and the nanoPE substrate with high-infrared (IR) transparency (92.1%, weighted based on human body radiation) results in effective radiative cooling. Wemore » further demonstrate that by coating nanoPE with a layer of Ag, the fiber/Ag/nanoPE mask shows a high IR reflectance (87.0%) and can be used for warming purposes. These multifunctional face mask designs can be explored for both outdoor and indoor applications to protect people from PM pollutants and simultaneously achieve personal thermal comfort.« less

  19. Influence of cooling face masks on nasal air conditioning and nasal geometry.

    PubMed

    Lindemann, J; Hoffmann, T; Koehl, A; Walz, E M; Sommer, F

    2017-06-01

    Nasal geometries and temperature of the nasal mucosa are the primary factors affecting nasal air conditioning. Data on intranasal air conditioning after provoking the trigeminal nerve with a cold stimulus simulating the effects of an arctic condition is still missing. The objective was to investigate the influence of skin cooling face masks on nasal air conditioning, mucosal temperature and nasal geometry. Standardized in vivo measurements of intranasal air temperature, humidity and mucosal temperature were performed in 55 healthy subjects at defined detection sites before and after wearing a cooling face mask. Measurements of skin temperature, rhinomanometry and acoustic rhinometry were accomplished. After wearing the face mask the facial skin temperature was significantly reduced. Intranasal air temperature did not change. Absolute humidity and mucosal temperature increased significantly. The acoustic rhinometric results showed a significant increase of the volumes and the cross-sectional areas. There was no change in nasal airflow. Nasal mucosal temperature, humidity of inhaled air, and volume of the anterior nose increased after application of a cold face mask. The response is mediated by the trigeminal nerve. Increased mucosal temperatures as well as changes in nasal geometries seem to guarantee sufficient steady intranasal nasal air conditioning.

  20. Hyper-realistic face masks: a new challenge in person identification.

    PubMed

    Sanders, Jet Gabrielle; Ueda, Yoshiyuki; Minemoto, Kazusa; Noyes, Eilidh; Yoshikawa, Sakiko; Jenkins, Rob

    2017-01-01

    We often identify people using face images. This is true in occupational settings such as passport control as well as in everyday social environments. Mapping between images and identities assumes that facial appearance is stable within certain bounds. For example, a person's apparent age, gender and ethnicity change slowly, if at all. It also assumes that deliberate changes beyond these bounds (i.e., disguises) would be easy to spot. Hyper-realistic face masks overturn these assumptions by allowing the wearer to look like an entirely different person. If unnoticed, these masks break the link between facial appearance and personal identity, with clear implications for applied face recognition. However, to date, no one has assessed the realism of these masks, or specified conditions under which they may be accepted as real faces. Herein, we examined incidental detection of unexpected but attended hyper-realistic masks in both photographic and live presentations. Experiment 1 (UK; n = 60) revealed no evidence for overt detection of hyper-realistic masks among real face photos, and little evidence of covert detection. Experiment 2 (Japan; n = 60) extended these findings to different masks, mask-wearers and participant pools. In Experiment 3 (UK and Japan; n = 407), passers-by failed to notice that a live confederate was wearing a hyper-realistic mask and showed limited evidence of covert detection, even at close viewing distance (5 vs. 20 m). Across all of these studies, viewers accepted hyper-realistic masks as real faces. Specific countermeasures will be required if detection rates are to be improved.

  1. Dead space variability of face masks for valved holding chambers.

    PubMed

    Amirav, Israel; Newhouse, Michael T

    2008-03-01

    Valved holding chambers with masks are commonly used to deliver inhaled medications to young children with asthma. Optimal mask properties such as their dead space volume have received little attention. The smaller the mask the more likely it is that a greater proportion of the dose in the VHC will be inhaled with each breath, thus speeding VHC emptying and improving overall aerosol delivery efficiency and dose. Masks may have different DSV and thus different performance. To compare both physical dead space and functional dead space of different face masks under various applied pressures. The DSV of three commonly used face masks of VHCs was measured by water displacement both under various pressures (to simulate real-life application, dynamic DSV) and under no pressure (static DSV). There was a great variability of both static and dynamic dead space among various face mask for VHCs, which is probably related to their flexibility. Different masks have different DSV characteristics. This variability should be taken into account when comparing the clinical efficacy of various VHCs.

  2. Face masks and basketball: NCAA division I consumer trends and a review of over-the-counter face masks.

    PubMed

    Gandy, Jessica R; Fossett, Lela; Wong, Brian J F

    2016-05-01

    This study aims to: 1) determine the current consumer trends of over-the-counter (OTC) and custom-made face mask usage among National Collegiate Athletic Association (NCAA) Division I athletic programs; and 2) provide a literature review of OTC face guards and a classified database. Literature review and survey. Consumer trends were obtained by contacting all 352 NCAA Division I programs. Athletic trainers present in the office when called answered the following questions: 1) "When an athlete breaks his or her nose, is a custom or generic face guard used?" and 2) "What brand is the generic face guard that is used?" Data was analyzed to determine trends among athletic programs. Also, a database of OTC devices available was generated using PubMed, Google, and manufacturer Web sites. Among the 352 NCAA Division I athletic programs, 254 programs participated in the survey (72% response rate). The majority preferred custom-made guards (46%). Disadvantages included high cost and slow manufacture turnaround time. Only 20% of the programs strictly used generic brands. For the face mask database, 10 OTC products were identified and classified into four categories based on design, with pricing ranging between $35.99 and $69.95. Only a handful of face masks exist for U.S. consumers, but none of them have been reviewed or classified by product design, sport application, price, and collegiate consumer use. This project details usage trends among NCAA Division I athletic programs and provides a list of available devices that can be purchased to protect the nose and face during sports. NA. Laryngoscope, 126:1054-1060, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Face Masks for Noninvasive Ventilation: Fit, Excess Skin Hydration, and Pressure Ulcers.

    PubMed

    Visscher, Marty O; White, Cynthia C; Jones, Jennifer M; Cahill, Thomas; Jones, Donna C; Pan, Brian S

    2015-11-01

    Pressure ulcers (stages III and IV) are serious safety events (ie, never events). Healthcare institutions are no longer reimbursed for costs to care for affected patients. Medical devices are the leading cause of pediatric pressure ulcers. Face masks for noninvasive ventilation were associated with a high percentage of pressure ulcers at our institution. A prospective cohort study investigated factors contributing to pressure ulcer development in 50 subjects using face masks for noninvasive ventilation. Color imaging, 3-dimensional surface imaging, and skin hydration measurements were used to identify early skin compromise and evaluate 3 interventions to reduce trauma: (1) a silicone foam dressing, (2) a water/polyethylene oxide hydrogel dressing, and (3) a flexible cloth mask. A novel mask fit technique was used to examine the impact of fit on the potential for skin compromise. Fifty subjects age 10.4 ± 9.1 y participated with color images for 22, hydration for 34, and mask fit analysis for 16. Of these, 69% had diagnoses associated with craniofacial anomalies. Stage I pressure ulcers were the most common injury. Skin hydration difference was 317 ± 29 for sites with erythema versus 75 ± 28 for sites without erythema (P < .05) and smallest for the cloth mask (P < .05). Fit distance metrics differed for the nasal, oronasal, and face shield interfaces, with threshold distances being higher for the oronasal mask than the others (P < .05). Areas of high contact were associated with skin erythema and pressure ulcers. This fit method is currently being utilized to select best-fit masks from available options, to identify the potential areas of increased tissue pressure, and to prevent skin injuries and their complications. Improvement of mask fit is an important priority for improving respiratory outcomes. Strategies to maintain normal skin hydration are important for protecting tissue integrity. Copyright © 2015 by Daedalus Enterprises.

  4. Pressure Ulcer Incidence in Patients Wearing Nasal-Oral Versus Full-Face Noninvasive Ventilation Masks.

    PubMed

    Schallom, Marilyn; Cracchiolo, Lisa; Falker, Antoinette; Foster, Jennifer; Hager, JoAnn; Morehouse, Tamara; Watts, Peggy; Weems, Linda; Kollef, Marin

    2015-07-01

    Device-related pressure ulcers from noninvasive ventilation masks alter skin integrity and cause patients discomfort. To examine the incidence, location, and stage of pressure ulcers and patients' comfort with a nasal-oral mask compared with a full-face mask. A before-after study of a convenience sample of patients with noninvasive ventilation orders in 5 intensive care units was conducted. Two groups of 100 patients each received either the nasal-oral mask or the full-face mask. Skin was assessed before the mask was applied and every 12 hours after that or upon mask removal. Comfort levels were assessed every 12 hours on a Likert scale of 1 to 5 (1, most comfortable). A pressure ulcer developed in 20% of patients in the nasal-oral mask group and 2% of patients in the full-face mask group (P < .001). Comfort scores were significantly lower (more comfortable) with the full-face mask (mean [SD], 1.9 [1.1]) than with the nasal-oral mask (mean [SD], 2.7 [1.2], P < .001). Neither mean hours worn nor percentage adherence differed significantly: 28.9 (SD, 27.2) hours and 92% for full-face mask and 25 (SD, 20.7) and 92% for nasal-oral mask. No patients who had a pressure ulcer develop with the nasal-oral mask had a pressure ulcer develop with the full-face mask. The full-face mask resulted in significantly fewer pressure ulcers and was more comfortable for patients. The full-face mask is a reasonable alternative to traditional nasal-oral masks for patients receiving noninvasive ventilation. ©2015 American Association of Critical-Care Nurses.

  5. Influence of face mask design on bag-valve-mask ventilation performance: a randomized simulation study.

    PubMed

    Na, J U; Han, S K; Choi, P C; Cho, J H; Shin, D H

    2013-10-01

    Different face mask designs can influence bag-valve-mask (BVM) ventilation performance during resuscitation. We compared a single-use, air-cushioned face mask (AM) with a reusable silicone face mask (SM) for quality of BVM ventilation on a manikin simulating cardiac arrest. Thirty-two physicians were recruited, and a prospective, randomized, crossover observational study was conducted after an American Heart Association-accredited basic life support provider course and standardized practice time were completed. Participants performed 12 cycles of BVM ventilation with both the AM and SM on a SmartMan lung simulator. Mean tidal volume was significantly higher in ventilations performed using the AM vs. the SM (548 ± 159 ml vs. 439 ± 163 ml, P < 0.01). In addition, the proportion of low-volume ventilation was significantly lower with the AM than the SM [6/12 (2-11) vs. 9/12 (5-12), P = 0.03]. Bag-valve-AM ventilation volume was not affected by the physical characteristics of the rescuers, except for sex. In contrast, bag-valve-SM ventilation volume was affected by most of the characteristics tested, including sex, height, weight, hand width, hand length, and grip power. The AM seems to be a more efficient face mask than the SM at delivering sufficient ventilation volumes. The performance of the AM did not seem to be associated with the physical characteristics of the rescuers, whereas that of the SM was affected by these factors. The SM may not be an appropriate face mask for performing one-person BVM ventilation during resuscitation for rescuers who are smaller in stature, have a smaller hand size, or have weaker grip power. © 2013 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  6. How do different brands of size 1 laryngeal mask airway compare with face mask ventilation in a dedicated laryngeal mask airway teaching manikin?

    PubMed

    Tracy, Mark Brian; Priyadarshi, Archana; Goel, Dimple; Lowe, Krista; Huvanandana, Jacqueline; Hinder, Murray

    2018-05-01

    International neonatal resuscitation guidelines recommend the use of laryngeal mask airway (LMA) with newborn infants (≥34 weeks' gestation or >2 kg weight) when bag-mask ventilation (BMV) or tracheal intubation is unsuccessful. Previous publications do not allow broad LMA device comparison. To compare delivered ventilation of seven brands of size 1 LMA devices with two brands of face mask using self-inflating bag (SIB). 40 experienced neonatal staff provided inflation cycles using SIB with positive end expiratory pressure (PEEP) (5 cmH 2 O) to a specialised newborn/infant training manikin randomised for each LMA and face mask. All subjects received prior education in LMA insertion and BMV. 12 415 recorded inflations for LMAs and face masks were analysed. Leak detected was lowest with i-gel brand, with a mean of 5.7% compared with face mask (triangular 42.7, round 35.7) and other LMAs (45.5-65.4) (p<0.001). Peak inspiratory pressure was higher with i-gel, with a mean of 28.9 cmH 2 O compared with face mask (triangular 22.8, round 25.8) and other LMAs (14.3-22.0) (p<0.001). PEEP was higher with i-gel, with a mean of 5.1 cmH 2 O compared with face mask (triangular 3.0, round 3.6) and other LMAs (0.6-2.6) (p<0.001). In contrast to other LMAs examined, i-gel had no insertion failures and all users found i-gel easy to use. This study has shown dramatic performance differences in delivered ventilation, mask leak and ease of use among seven different brands of LMA tested in a manikin model. This coupled with no partial or complete insertion failures and ease of use suggests i-gel LMA may have an expanded role with newborn resuscitation as a primary resuscitation device. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. Method To Display Data On A Face Mask

    NASA Technical Reports Server (NTRS)

    Moore, Kevin-Duron

    1995-01-01

    Proposed electronic instrument displays information on diver's or firefighter's face mask. Includes mask, prism, electronic readouts, transceiver and control electronics. Mounted at periphery of diver's field of view to provide data on elapsed time, depth, pressure, and temperature. Provides greater safety and convenience to user.

  8. Masking with faces in central visual field under a variety of temporal schedules.

    PubMed

    Daar, Marwan; Wilson, Hugh R

    2015-11-01

    With a few exceptions, previous studies have explored masking using either a backward mask or a common onset trailing mask, but not both. In a series of experiments, we demonstrate the use of faces in central visual field as a viable method to study the relationship between these two types of mask schedule. We tested observers in a two alternative forced choice face identification task, where both target and mask comprised synthetic faces, and show that a simple model can successfully predict masking across a variety of masking schedules ranging from a backward mask to a common onset trailing mask and a number of intermediate variations. Our data are well accounted for by a window of sensitivity to mask interference that is centered at around 100 ms. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. The total face mask is more comfortable than the oronasal mask in noninvasive ventilation but is not associated with improved outcome.

    PubMed

    Chacur, Fernando Hauaji; Vilella Felipe, Luis Marcelo; Fernandes, Cintia Gonçalves; Lazzarini, Luiz Claudio Oliveira

    2011-01-01

    Noninvasive positive-pressure ventilation (NPPV) is commonly used to improve ventilation and oxygenation and avoid endotracheal intubation and mechanical ventilation. Although clinically indicated, most patients fail to use NPPV due to mask intolerance. A total face mask was designed to increase compliance, but whether this translates into better outcome (improvement in clinical and blood gas parameters and less intubation) is unknown. We compared the evolution of the clinical parameters, blood gases, levels of ventilatory support and rate of endotracheal intubation using the total face mask or the traditional oronasal mask during NPPV. A total of 60 patients were randomized to use either mask during NPPV. The clinical and laboratory parameters, as well as the level of ventilatory support were recorded at different intervals in both groups for up to 6 h. In addition, the tolerance for each mask and the need for endotracheal intubation were compared. Patients tolerated the total face mask significantly better (p = 0.0010) and used NPPV for a longer time (p = 0.0017) when compared with the oronasal mask. Just 1 patient switched to the total face mask because of intolerance. Although better tolerated, the rate of endotracheal intubation was similar in both groups (p = 0.4376), as was the clinical and laboratory evolution. The total face mask was more comfortable, allowing the patients to tolerate NPPV longer; however, these accomplishments did not translate into a better outcome. Due to its comfort, the total face mask should be available, at least as an option, in units where NPPVs are routinely applied. Copyright © 2011 S. Karger AG, Basel.

  10. Influence of mask type and mask position on the effectiveness of bag-mask ventilation in a neonatal manikin.

    PubMed

    Deindl, Philipp; O'Reilly, Megan; Zoller, Katharina; Berger, Angelika; Pollak, Arnold; Schwindt, Jens; Schmölzer, Georg M

    2014-01-01

    Anatomical face mask with an air cushion rim might be placed accidentally in a false orientation on the newborn's face or filled with various amounts of air during neonatal resuscitation. Both false orientation as well as variable filling may reduce a tight seal and therefore hamper effective positive pressure ventilation (PPV). We aimed to measure the influence of mask type and mask position on the effectiveness of PPV. Twenty neonatal staff members delivered PPV to a modified, leak-free manikin. Resuscitation parameters were recorded using a self-inflatable bag PPV with an Intersurgical anatomical air cushion rim face mask (IS) and a size 0/1 Laerdal round face mask. Three different positions of the IS were tested: correct position, 90° and 180° rotation in reference to the midline of the face. IS masks in each correct position on the face but with different inflation of the air cushion (empty, 10, 20 and 30 mL). Mask leak was similar with mask rotation to either 90° or 180° but significantly increased from 27 (13-73) % with an adequate filled IS mask compared to 52 (16-83) % with an emptied air cushion rim. Anatomical-shaped face mask had similar mask leaks compared to round face mask. A wrongly positioned anatomical-shaped mask does not influence mask leak. Mask leak significantly increased once the air cushion rim was empty, which may cause failure in mask PPV.

  11. Nasal versus face mask for multiple-breath washout technique in preterm infants.

    PubMed

    Schulzke, S M; Deeptha, K; Sinhal, S; Baldwin, D N; Pillow, J J

    2008-09-01

    The large dead space associated with face masks might impede the accuracy and feasibility of multiple-breath washout (MBW) measurements in small infants. We asked if a low dead space nasal mask would provide measurements of resting lung volume and ventilation inhomogeneity comparable to those obtained with a face mask, when using the MBW technique. Unsedated preterm infants breathing without mechanical assistance and weighing between 1.50 and 2.49 kg were studied. Paired MBW tests with nasal and face masks were obtained using sulphur hexafluoride (SF(6)) as the tracer gas. The order of mask application was quasi-randomized. Bland-Altman method and intraclass correlation coefficient were used to analyze outcomes. Measurements were obtained in 20 infants with a mean (SD) postmenstrual age of 36 (1.4) w and a test weight of 2.0 (0.3) kg. The mean difference (95% CI) for nasal vs. face mask was -3.2 breaths/min (-6.2, -0.1 breaths/min) for respiratory rate, -1.0 ml/kg (-2.3, 0.3 ml/kg) for lung volume, 0.6 (0.1, 1.1) for lung clearance index, 0.2 (0.1, 0.3) for first to zeroeth moment ratio and 1.33 (0.6, 2.4) for second to zeroeth moment ratio. Paired measurements of lung volume showed acceptable agreement and good correlation, but there was poor agreement and poor correlation between indices of ventilation inhomogeneity obtained with the two masks. Functional dead space of the nasal mask was similar to that of the face mask despite its smaller water displacement volume. During MBW in infants below 2.5 kg body weight, a nasal mask results in comparable lung volume measurements. Indices of ventilation inhomogeneity may not be directly comparable using masks with different dead space. (c) 2008 Wiley-Liss, Inc.

  12. Simple solution for difficult face mask ventilation in children with orofacial clefts.

    PubMed

    Veerabathula, Prardhana; Patil, Manajeet; Upputuri, Omkar; Durga, Padmaja

    2014-10-01

    Significant air leak from the facial cleft predisposes to difficult mask ventilation. The reported techniques of use of sterile gauze, larger face mask and laryngeal mask airway after intravenous induction have limited application in uncooperative children. We describe the use of dental impression material molded to the facial contour to cover the facial defect and aid ventilation with an appropriate size face mask in a child with a bilateral Tessier 3 anomaly. © 2014 John Wiley & Sons Ltd.

  13. An investigation into the efficiency of disposable face masks.

    PubMed Central

    Rogers, K B

    1980-01-01

    Disposable face masks used in hospitals have been assessed for the protection afforded the patient and the wearer by challenges of simulated natural conditions of stress. Operating theatre masks made of synthetic materials allow the wearer to breathe through the masks, and these have been shown to protect the patient well but the wearer slightly less. Cheaper paper masks are worn for ward duties, and of these only the Promask protected in area in front of the wearer: air does not pass through this mask, expired air is prevented from passing forward, and the wearer breathes unfiltered air. All the other paper masks tested allowed many bacteria-laden particles to pass through them. PMID:7440756

  14. Disposable surgical face masks for preventing surgical wound infection in clean surgery.

    PubMed

    Lipp, Allyson; Edwards, Peggy

    2014-02-17

    Surgical face masks were originally developed to contain and filter droplets containing microorganisms expelled from the mouth and nasopharynx of healthcare workers during surgery, thereby providing protection for the patient. However, there are several ways in which surgical face masks could potentially contribute to contamination of the surgical wound, e.g. by incorrect wear or by leaking air from the side of the mask due to poor string tension. To determine whether disposable surgical face masks worn by the surgical team during clean surgery prevent postoperative surgical wound infection. We searched The Cochrane Wounds Group Specialised Register on 23 October 2013; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL. Randomised controlled trials (RCTs) and quasi-randomised controlled trials comparing the use of disposable surgical masks with the use of no mask. Two review authors extracted data independently. Three trials were included, involving a total of 2113 participants. There was no statistically significant difference in infection rates between the masked and unmasked group in any of the trials. From the limited results it is unclear whether the wearing of surgical face masks by members of the surgical team has any impact on surgical wound infection rates for patients undergoing clean surgery.

  15. Measurements from preterm infants to guide face mask size.

    PubMed

    O'Shea, Joyce E; Thio, Marta; Owen, Louise S; Wong, Connie; Dawson, Jennifer A; Davis, Peter G

    2016-07-01

    International guidelines recommend that an appropriately sized face mask for providing positive pressure ventilation should cover the mouth and nose but not the eyes and should not overlap the chin. This study aimed to measure the dimensions of preterm infants' faces and compare these with the size of the most commonly available face masks (external diameter 50 mm) and the smallest masks available (external diameters 35 and 42 mm). Infants 24-33 weeks' postmenstrual age (PMA) were photographed in a standardised manner. Images were analysed using ImageJ software (National Institute of Health, USA) to calculate the distance from the nasofrontal groove to the mental protuberance. This facial measurement corresponds to the external diameter of an optimally fitting mask. A cohort of 107 infants between 24 and 33 weeks' gestational age, including at least 10 infants per week of gestation, was photographed within 72 h after birth and weekly until 33 weeks' PMA. 347 photographs were analysed. Infants of 24, 26, 28, 30 and 32 weeks' PMA had mean (SD) facial measurements of 32 (2), 36 (3), 38 (4), 41 (2) and 43 (4) mm, respectively. There were no significant differences when examined by gender or when small for gestational age infants were excluded. The smallest size of some brands of mask is too large for many preterm infants. Masks of 35 mm diameter are suitable for infants <29 weeks' PMA or 1000 g. Masks of 42 mm diameter are suitable for infants 27-33 weeks' PMA or 750-2500 g. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  16. Redesign of an Open-System Oxygen Face Mask With Mainstream Capnometer for Children.

    PubMed

    Napolitano, Natalie; Nishisaki, Akira; Buffman, Hayley S; Leffelman, Jessica; Maltese, Matthew R; Nadkarni, Vinay M

    2017-01-01

    Partial pressure of end-tidal carbon dioxide (P ETCO 2 ) monitoring in children is important to detect apnea or hypopnea early to intervene before hypoxemia develops. Monitoring P ETCO 2 in children without a tracheal tube is challenging. To improve P ETCO 2 measurement accuracy in a commercially available mask with a mainstream CO 2 detector, we implemented design changes with deform-and-hold shaping technology and anterior-posterior adjustment of the expiratory gas flow cup. Two sizes of redesigned face masks (small for 7-20 kg, medium for 10-40 kg) were evaluated. Initial bench testing used a simulator modeling a spontaneously breathing infant and child with a natural airway. An infant/child manikin head was connected to the breathing lung simulator. A mass flow controller provided expiratory CO 2 . Mask fit was then evaluated on healthy human subjects to identify anatomical features associated with good fit, defined as square shape capnography waveform during expiration. A 3-dimensional digital scan was used to quantify anatomical features. The gaps between face mask rims and facial surface were manually measured. Bench testing revealed a P ETCO 2 difference of 3.4 ± 1.5 mm Hg between a measured P ETCO 2 by the redesigned mask and CO 2 concentration at trachea, as compared with 6.7 ± 6.2 mm Hg between P ETCO 2 measured by nasal cannula and trachea (P < .001). In the human mask fit study, 35 children (13 ± 4 kg) with the small mask and 38 (24 ± 8 kg) with the medium mask were evaluated. Capnography tracing was successfully obtained in 86% of the small and 100% of the medium masks. In children with small-size masks, the gap between the face mask rim and the child's face was not statistically different among those with good mask fit and without (1.0 ± 1.5 mm vs 1.4 ± 1.9 mm, P = .73). P ETCO 2 measurement by a redesigned open-system face mask with a mainstream CO 2 detector was accurate in the bench setting. The redesigned face mask can attain good mask fit

  17. Comparison of Ventilation With One-Handed Mask Seal With an Intraoral Mask Versus Conventional Cuffed Face Mask in a Cadaver Model: A Randomized Crossover Trial.

    PubMed

    Amack, Andrew J; Barber, Gary A; Ng, Patrick C; Smith, Thomas B; April, Michael D

    2017-01-01

    We compare received minute volume with an intraoral mask versus conventional cuffed face mask among medics obtaining a 1-handed mask seal on a cadaver model. This study comprised a randomized crossover trial of adult US Army combat medic volunteers participating in a cadaver laboratory as part of their training. We randomized participants to obtain a 1-handed mask seal during ventilation of a fresh unembalmed cadaver, first using either an intraoral airway device or conventional cuffed face mask. Participants obtained a 1-handed mask seal while a ventilator delivered 10 standardized 750-mL breaths during 1 minute. After a 5-minute rest period, they repeated the study with the alternative mask. The primary outcome measure was received minute volume as measured by a respirometer. Of 27 recruited participants, all completed the study. Median received minute volume was higher with the intraoral mask compared with conventional cuffed mask by 1.7 L (95% confidence interval 1.0 to 1.9 L; P<.001). The intraoral mask resulted in greater received minute volume received compared with conventional cuffed face mask during ventilation with a 1-handed mask seal in a cadaver model. The intraoral mask may prove a useful airway adjunct for ventilation. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  18. Face-masks for facial atopic eczema: consider a hydrocolloid dressing.

    PubMed

    Rademaker, Marius

    2013-08-01

    Facial involvement of atopic eczema in young children can be difficult to manage. Chronic scratching and rubbing, combined with parental reluctance to use topical corticosteroids on the face, often results in recalcitrant facial eczema. While wet wraps are a useful management option for moderate/severe atopic eczema involving the trunk and limbs they are difficult to use on the face. We describe the use of a face-mask using a widely available adhesive hydrocolloid dressing (DuoDerm extra thin) in three children with recalcitrant facial atopic eczema. Symptomatic control of itch or soreness was obtained within hours and the facial atopic eczema was markedly improved by 7 days. The face-masks were easy to apply, each lasting 1-4 days. One patient had a single adjuvant application of a potent topical corticosteroid under the hydrocolloid dressing. All three patients had long remissions (greater than 3 months) of their facial eczema, although all continued to have significant eczema involving their trunk and limbs. Face-masks made from hydrocolloid dressings, with or without topical corticosteroids, are worth considering in children with recalcitrant facial eczema. © 2012 The Author. Australasian Journal of Dermatology © 2012 The Australasian College of Dermatologists.

  19. Interactions between concentric form-from-structure and face perception revealed by visual masking but not adaptation

    PubMed Central

    Feczko, Eric; Shulman, Gordon L.; Petersen, Steven E.; Pruett, John R.

    2014-01-01

    Findings from diverse subfields of vision research suggest a potential link between high-level aspects of face perception and concentric form-from-structure perception. To explore this relationship, typical adults performed two adaptation experiments and two masking experiments to test whether concentric, but not nonconcentric, Glass patterns (a type of form-from-structure stimulus) utilize a processing mechanism shared by face perception. For the adaptation experiments, subjects were presented with an adaptor for 5 or 20 s, prior to discriminating a target. In the masking experiments, subjects saw a mask, then a target, and then a second mask. Measures of discriminability and bias were derived and repeated measures analysis of variance tested for pattern-specific masking and adaptation effects. Results from Experiment 1 show no Glass pattern-specific effect of adaptation to faces; results from Experiment 2 show concentric Glass pattern masking, but not adaptation, may impair upright/inverted face discrimination; results from Experiment 3 show concentric and radial Glass pattern masking impaired subsequent upright/inverted face discrimination more than translational Glass pattern masking; and results from Experiment 4 show concentric and radial Glass pattern masking impaired subsequent face gender discrimination more than translational Glass pattern masking. Taken together, these findings demonstrate interactions between concentric form-from-structure and face processing, suggesting a possible common processing pathway. PMID:24563526

  20. Sandwich masking eliminates both visual awareness of faces and face-specific brain activity through a feedforward mechanism.

    PubMed

    Harris, Joseph A; Wu, Chien-Te; Woldorff, Marty G

    2011-06-07

    It is generally agreed that considerable amounts of low-level sensory processing of visual stimuli can occur without conscious awareness. On the other hand, the degree of higher level visual processing that occurs in the absence of awareness is as yet unclear. Here, event-related potential (ERP) measures of brain activity were recorded during a sandwich-masking paradigm, a commonly used approach for attenuating conscious awareness of visual stimulus content. In particular, the present study used a combination of ERP activation contrasts to track both early sensory-processing ERP components and face-specific N170 ERP activations, in trials with versus without awareness. The electrophysiological measures revealed that the sandwich masking abolished the early face-specific N170 neural response (peaking at ~170 ms post-stimulus), an effect that paralleled the abolition of awareness of face versus non-face image content. Furthermore, however, the masking appeared to render a strong attenuation of earlier feedforward visual sensory-processing signals. This early attenuation presumably resulted in insufficient information being fed into the higher level visual system pathways specific to object category processing, thus leading to unawareness of the visual object content. These results support a coupling of visual awareness and neural indices of face processing, while also demonstrating an early low-level mechanism of interference in sandwich masking.

  1. Competing for Consciousness: Prolonged Mask Exposure Reduces Object Substitution Masking

    ERIC Educational Resources Information Center

    Goodhew, Stephanie C.; Visser, Troy A. W.; Lipp, Ottmar V.; Dux, Paul E.

    2011-01-01

    In object substitution masking (OSM) a sparse, temporally trailing 4-dot mask impairs target identification, even though it has different contours from, and does not spatially overlap with the target. Here, we demonstrate a previously unknown characteristic of OSM: Observers show reduced masking at prolonged (e.g., 640 ms) relative to intermediate…

  2. Use of face masks in a primary care outpatient setting in Hong Kong: Knowledge, attitudes and practices.

    PubMed

    Ho, H S W

    2012-12-01

    To assess if a knowledge gap exists in the correct use of face masks, and to explore the correlations between knowledge, attitudes and practices regarding the use of face masks among outpatients and their caregivers in an outpatient clinic in Hong Kong. Cross-sectional study. Outpatients and their caregivers who were present at an outpatient setting in Hong Kong were invited to participate in this survey. All participants were asked to complete a self-administered closed-ended questionnaire about their knowledge, attitudes and practices regarding the use of face masks. Data were described using descriptive statistics and correlation coefficients. Among the 399 respondents, 52% knew the correct steps in wearing a face mask, and their attitudes toward face masks were generally positive. Further analyses showed that respondents were more likely to wear a face mask at a clinic than in a public place or at home. Moreover, respondents were more likely to wear a face mask to protect others against influenza-like illness (ILI) than for self-protection. There was low to moderate correlation between attitudes and practices (correlation coefficient 0.26, P < 0.05). This study identified a knowledge gap in the correct use of face masks among outpatients and their caregivers; attitudes and practices regarding the use of face masks were generally positive, but correlation was not high. It is recommended that public health education campaigns should tailor efficient programmes to combat ILI transmission among outpatient clinic populations by improving knowledge about the correct use of face masks. Copyright © 2012 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  3. Combined tool approach is 100% successful for emergency football face mask removal.

    PubMed

    Copeland, Aaron J; Decoster, Laura C; Swartz, Erik E; Gattie, Eric R; Gale, Stephanie D

    2007-11-01

    To compare effectiveness of two techniques for removing football face masks: cutting loop straps [cutting tool: FMXtractor (FMX)] or removing screws with a cordless screwdriver and using the FMXtractor as needed for failed removals [combined tool (CT)]. Null hypotheses: no differences in face mask removal success, removal time or difficulty between techniques or helmet characteristics. Retrospective, cross-sectional. NOCSAE-certified helmet reconditioning plants. 600 used high school helmets. Face mask removal attempted with two techniques. Success, removal time, rating of perceived exertion (RPE). Both techniques were effective [CT 100% (300/300); FMX 99.4% (298/300)]. Use of the backup FMXtractor in CT trials was required in 19% of trials. There was significantly (P<0.001) less call for the backup tool in helmets with silver screws (6%) than in helmets with other screws (31%). Mean removal time was 44.51+/-18.79s (CT: 37.84+/-15.37s, FMX: 51.21+/-19.54s; P<0.001). RPE was different between techniques (CT: 1.83+/-1.20, FMX: 3.11+/-1.27; P<0.001). Removal from helmets with silver screws was faster (Silver=33.38+/-11.03, Others=42.18+/-17.64; P<0.001) and easier (Silver=1.42+/-0.89, Other=2.23+/-1.33; P<0.001). CT was faster and easier than FMX. Most CT trials were completed with the screwdriver alone; helmets with silver screws had 94% screwdriver success. Clinically, these findings are important because this and other research shows that compared to removal with cutting tools, screwdriver removal decreases time, difficulty and helmet movement (reducing potential for iatrogenic injury). The combined-tool approach captures benefits of the screwdriver while offering a contingency for screw removal failure. Teams should use degradation-resistant screws. Sports medicine professionals must be prepared with appropriate tools and techniques to efficiently remove the face mask from an injured football player's helmet.

  4. A randomised crossover comparison of mouth-to-face-shield ventilation and mouth-to-pocket-mask ventilation by surf lifeguards in a manikin.

    PubMed

    Adelborg, K; Bjørnshave, K; Mortensen, M B; Espeseth, E; Wolff, A; Løfgren, B

    2014-07-01

    Thirty surf lifeguards (mean (SD) age: 25.1 (4.8) years; 21 male, 9 female) were randomly assigned to perform 2 × 3 min of cardiopulmonary resuscitation on a manikin using mouth-to-face-shield ventilation (AMBU LifeKey) and mouth-to-pocket-mask ventilation (Laerdal Pocket Mask). Interruptions in chest compressions, effective ventilation (visible chest rise) ratio, tidal volume and inspiratory time were recorded. Interruptions in chest compressions per cycle were increased with mouth-to-face-shield ventilation (mean (SD) 8.6 (1.7) s) compared with mouth-to-pocket-mask ventilation (6.9 (1.2) s, p < 0.0001). The proportion of effective ventilations was less using mouth-to-face-shield ventilation (199/242 (82%)) compared with mouth-to-pocket-mask ventilation (239/240 (100%), p = 0.0002). Tidal volume was lower using mouth-to-face-shield ventilation (mean (SD) 0.36 (0.20) l) compared with mouth-to-pocket-mask ventilation (0.45 (0.20) l, p = 0.006). No differences in inspiratory times were observed between mouth-to-face-shield ventilation and mouth-to-pocket-mask ventilation. In conclusion, mouth-to-face-shield ventilation increases interruptions in chest compressions, reduces the proportion of effective ventilations and decreases delivered tidal volumes compared with mouth-to-pocket-mask ventilation. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

  5. The extended functional neuroanatomy of emotional processing biases for masked faces in major depressive disorder.

    PubMed

    Victor, Teresa A; Furey, Maura L; Fromm, Stephen J; Bellgowan, Patrick S F; Öhman, Arne; Drevets, Wayne C

    2012-01-01

    Major depressive disorder (MDD) is associated with a mood-congruent processing bias in the amygdala toward face stimuli portraying sad expressions that is evident even when such stimuli are presented below the level of conscious awareness. The extended functional anatomical network that maintains this response bias has not been established, however. To identify neural network differences in the hemodynamic response to implicitly presented facial expressions between depressed and healthy control participants. Unmedicated-depressed participants with MDD (n=22) and healthy controls (HC; n=25) underwent functional MRI as they viewed face stimuli showing sad, happy or neutral face expressions, presented using a backward masking design. The blood-oxygen-level dependent (BOLD) signal was measured to identify regions where the hemodynamic response to the emotionally valenced stimuli differed between groups. The MDD subjects showed greater BOLD responses than the controls to masked-sad versus masked-happy faces in the hippocampus, amygdala and anterior inferotemporal cortex. While viewing both masked-sad and masked-happy faces relative to masked-neutral faces, the depressed subjects showed greater hemodynamic responses than the controls in a network that included the medial and orbital prefrontal cortices and anterior temporal cortex. Depressed and healthy participants showed distinct hemodynamic responses to masked-sad and masked-happy faces in neural circuits known to support the processing of emotionally valenced stimuli and to integrate the sensory and visceromotor aspects of emotional behavior. Altered function within these networks in MDD may establish and maintain illness-associated differences in the salience of sensory/social stimuli, such that attention is biased toward negative and away from positive stimuli.

  6. Fabrication technique for a custom face mask for the treatment of obstructive sleep apnea.

    PubMed

    Prehn, Ronald S; Colquitt, Tom

    2016-05-01

    The development of the positive airway pressure custom mask (TAP-PAP CM) has changed the treatment of obstructive sleep apnea. The TAP-PAP CM is used in continuous positive airway pressure therapy (CPAP) and is fabricated from the impression of the face. This mask is then connected to a post screwed into the mechanism of the TAP3 (Thornton Anterior Positioner) oral appliance. This strapless CPAP face mask features an efficient and stable CPAP interface with mandibular stabilization (Hybrid Therapy). A technique with a 2-stage polyvinyl siloxane face impression is described that offers improvements over the established single-stage face impression. This 2-stage impression technique eliminates problems inherent in the single-stage face impression, including voids, compressed tissue, inadequate borders, and a rushed experience due to the setting time of the single stage. The result is a custom mask with an improved seal to the CPAP device. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  7. The effects of fixed and removable face masks on maxillary deficiencies in growing patients.

    PubMed

    Jamilian, Abdolreza; Showkatbakhsh, Rahman; Taban, Tannaz

    2012-01-01

    To compare the effects of two different types of face masks in the treatment of Class III malocclusions with maxillary deficiency in growing patients. Forty-three patients (21 boys and 22 girls) with maxillary deficiencies were selected. Twenty-one patients (10 boys and 11 girls) with a mean age of 8.9 ± 1.4 years were treated with maxillary removable appliances and face masks. Twenty-two patients (10 boys and 12 girls) with a mean age of 9.3 ± 1.2 years were treated with maxillary fixed appliances and face masks. Lateral cephalograms obtained at the beginning and end of the study were analyzed. Paired t tests and Wilcoxon tests showed that SNA and ANB significantly increased in both groups. The Mann-Whitney test showed that there were no statistically significant differences between the two groups except for U1-SN, which increased by 6.2 ± 7.1 degrees in the removable face mask group and 11.1 ± 6.9 degrees in the fixed face mask group (P < .02). Both treatment modalities were successful in moving the maxilla forward. However, the maxillary incisors had more labial inclination in the fixed appliance group.

  8. Respiratory Source Control Using Surgical Masks With Nanofiber Media

    PubMed Central

    Skaria, Shaji D.; Smaldone, Gerald C.

    2014-01-01

    Background: Potentially infected individuals (‘source’) are sometimes encouraged to use face masks to reduce exposure of their infectious aerosols to others (‘receiver’). To improve compliance with Respiratory Source Control via face mask and therefore reduce receiver exposure, a mask should be comfortable and effective. We tested a novel face mask designed to improve breathability and filtration using nanofiber filtration. Methods: Using radiolabeled test aerosols and a calibrated exposure chamber simulating source to receiver interaction, facepiece function was measured with a life-like ventilated manikin model. Measurements included mask airflow resistance (pressure difference during breathing), filtration, (mask capture of exhaled radiolabeled test aerosols), and exposure (the transfer of ‘infectious’ aerosols from the ‘source’ to a ‘receiver’). Polydisperse aerosols were measured at the source with a mass median aerodynamic diameter of 0.95 µm. Approximately 90% of the particles were <2.0 µm. Tested facepieces included nanofiber prototype surgical masks, conventional surgical masks, and for comparison, an N95-class filtering facepiece respirator (commonly known as an ‘N95 respirator’). Airflow through and around conventional surgical face mask and nanofiber prototype face mask was visualized using Schlieren optical imaging. Results: Airflow resistance [ΔP, cmH2O] across sealed surgical masks (means: 0.1865 and 0.1791 cmH2O) approached that of the N95 (mean: 0.2664 cmH2O). The airflow resistance across the nanofiber face mask whether sealed or not sealed (0.0504 and 0.0311 cmH2O) was significantly reduced in comparison. In addition, ‘infected’ source airflow filtration and receiver exposure levels for nanofiber face masks placed on the source were comparable to that achieved with N95 placed on the source; 98.98% versus 82.68% and 0.0194 versus 0.0557, respectively. Compared to deflection within and around the conventional face

  9. Respiratory source control using surgical masks with nanofiber media.

    PubMed

    Skaria, Shaji D; Smaldone, Gerald C

    2014-07-01

    Potentially infected individuals ('source') are sometimes encouraged to use face masks to reduce exposure of their infectious aerosols to others ('receiver'). To improve compliance with Respiratory Source Control via face mask and therefore reduce receiver exposure, a mask should be comfortable and effective. We tested a novel face mask designed to improve breathability and filtration using nanofiber filtration. Using radiolabeled test aerosols and a calibrated exposure chamber simulating source to receiver interaction, facepiece function was measured with a life-like ventilated manikin model. Measurements included mask airflow resistance (pressure difference during breathing), filtration, (mask capture of exhaled radiolabeled test aerosols), and exposure (the transfer of 'infectious' aerosols from the 'source' to a 'receiver'). Polydisperse aerosols were measured at the source with a mass median aerodynamic diameter of 0.95 µm. Approximately 90% of the particles were <2.0 µm. Tested facepieces included nanofiber prototype surgical masks, conventional surgical masks, and for comparison, an N95-class filtering facepiece respirator (commonly known as an 'N95 respirator'). Airflow through and around conventional surgical face mask and nanofiber prototype face mask was visualized using Schlieren optical imaging. Airflow resistance [ΔP, cmH2O] across sealed surgical masks (means: 0.1865 and 0.1791 cmH2O) approached that of the N95 (mean: 0.2664 cmH2O). The airflow resistance across the nanofiber face mask whether sealed or not sealed (0.0504 and 0.0311 cmH2O) was significantly reduced in comparison. In addition, 'infected' source airflow filtration and receiver exposure levels for nanofiber face masks placed on the source were comparable to that achieved with N95 placed on the source; 98.98% versus 82.68% and 0.0194 versus 0.0557, respectively. Compared to deflection within and around the conventional face masks, Schlieren optical imaging demonstrated enhanced

  10. Effectiveness of face masks used to protect Beijing residents against particulate air pollution.

    PubMed

    Cherrie, John W; Apsley, Andrew; Cowie, Hilary; Steinle, Susanne; Mueller, William; Lin, Chun; Horwell, Claire J; Sleeuwenhoek, Anne; Loh, Miranda

    2018-06-01

    Many residents in Beijing use disposable face masks in an attempt to protect their health from high particulate matter (PM) concentrations. Retail masks may be certified to local or international standards, but their real-life performance may not confer the exposure reduction potential that is marketed. This study aimed to evaluate the effectiveness of a range of face masks that are commercially available in China. Nine masks claiming protection against fine PM (PM 2.5 ) were purchased from consumer outlets in Beijing. The masks' filtration efficiency was tested by drawing airborne diesel exhaust through a section of the material and measuring the PM 2.5 and black carbon (BC) concentrations upstream and downstream of the filtering medium. Four masks were selected for testing on volunteers. Volunteers were exposed to diesel exhaust inside an experimental chamber while performing sedentary tasks and active tasks. BC concentrations were continuously monitored inside and outside the mask. The mean per cent penetration for each mask material ranged from 0.26% to 29%, depending on the flow rate and mask material. In the volunteer tests, the average total inward leakage (TIL) of BC ranged from 3% to 68% in the sedentary tests and from 7% to 66% in the active tests. Only one mask type tested showed an average TIL of less than 10%, under both test conditions. Many commercially available face masks may not provide adequate protection, primarily due to poor facial fit. Our results indicate that further attention should be given to mask design and providing evidence-based guidance to consumers. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Activity in Face-Responsive Brain Regions is Modulated by Invisible, Attended Faces: Evidence from Masked Priming

    PubMed Central

    Eger, Evelyn; Dolan, Raymond; Henson, Richard N.

    2009-01-01

    It is often assumed that neural activity in face-responsive regions of primate cortex correlates with conscious perception of faces. However, whether such activity occurs without awareness is still debated. Using functional magnetic resonance imaging (fMRI) in conjunction with a novel masked face priming paradigm, we observed neural modulations that could not be attributed to perceptual awareness. More specifically, we found reduced activity in several classic face-processing regions, including the “fusiform face area,” “occipital face area,” and superior temporal sulcus, when a face was preceded by a briefly flashed image of the same face, relative to a different face, even when 2 images of the same face differed. Importantly, unlike most previous studies, which have minimized awareness by using conditions of inattention, the present results occurred when the stimuli (the primes) were attended. By contrast, when primes were perceived consciously, in a long-lag priming paradigm, we found repetition-related activity increases in additional frontal and parietal regions. These data not only demonstrate that fMRI activity in face-responsive regions can be modulated independently of perceptual awareness, but also document where such subliminal face-processing occurs (i.e., restricted to face-responsive regions of occipital and temporal cortex) and to what extent (i.e., independent of the specific image). PMID:18400791

  12. Use of face masks by non-scrubbed operating room staff: a randomized controlled trial.

    PubMed

    Webster, Joan; Croger, Sarah; Lister, Carolyn; Doidge, Michelle; Terry, Michael J; Jones, Ian

    2010-03-01

    Ambiguity remains about the effectiveness of wearing surgical face masks. The purpose of this study was to assess the impact on surgical site infections (SSIs) when non-scrubbed operating room staff did not wear surgical face masks. Eight hundred twenty-seven participants undergoing elective or emergency obstetric, gynecological, general, orthopaedic, breast or urological surgery in an Australian tertiary hospital were enrolled. Complete follow-up data were available for 811 patients (98.1%). Operating room lists were randomly allocated to a 'Mask group' (all non-scrubbed staff wore a mask) or 'No Mask group' (none of the non-scrubbed staff wore masks). The primary end point, SSI was identified using in-patient surveillance; post discharge follow-up and chart reviews. The patient was followed for up to six weeks. Overall, 83 (10.2%) surgical site infections were recorded; 46/401 (11.5%) in the Masked group and 37/410 (9.0%) in the No Mask group; odds ratio (OR) 0.77 (95% confidence interval (CI) 0.49 to 1.21), p = 0.151. Independent risk factors for surgical site infection included: any pre-operative stay (adjusted odds ratio [aOR], 0.43 (95% CI, 0.20; 0.95), high BMI aOR, 0.38 (95% CI, 0.17; 0.87), and any previous surgical site infection aOR, 0.40 (95% CI, 0.17; 0.89). Surgical site infection rates did not increase when non-scrubbed operating room personnel did not wear a face mask.

  13. Football Face-Mask Removal With a Cordless Screwdriver on Helmets Used for at Least One Season of Play

    PubMed Central

    Decoster, Laura C; Shirley, Chandra P; Swartz, Erik E

    2005-01-01

    that demonstrated quicker access time and reduced head movement associated with the use of the screwdriver compared with cutting tools, the former may be a good tool for face-mask removal. However, an appropriate cutting tool must be immediately available should the screwdriver fail. Helmet hardware adjacent to ear holes was more vulnerable to failure, perhaps because it is protected by less padding than the top hardware. Possible causes of the higher failure rate at school 1 are the use of hardware materials subject to rust and corrosion and differences in helmet brand; these areas warrant future research and rules consideration. PMID:16284636

  14. Effect of facial material softness and applied force on face mask dead volume, face mask seal, and inhaled corticosteroid delivery through an idealized infant replica.

    PubMed

    Carrigy, Nicholas B; O'Reilly, Connor; Schmitt, James; Noga, Michelle; Finlay, Warren H

    2014-08-01

    During the aerosol delivery device design and optimization process, in vitro lung dose (LD) measurements are often performed using soft face models, which may provide a more clinically relevant representation of face mask dead volume (MDV) and face mask seal (FMS) than hard face models. However, a comparison of MDV, FMS, and LD for hard and soft face models is lacking. Metal, silicone, and polyurethane represented hard, soft, and very soft facial materials, respectively. MDV was measured using a water displacement technique. FMS was measured using a valved holding chamber (VHC) flow rate technique. The LD of beclomethasone dipropionate (BDP) delivered via a 100-μg Qvar® pressurized metered dose inhaler with AeroChamber Plus® Flow-Vu® VHC and Small Mask, defined as that which passes through the nasal airways of the idealized infant geometry, was measured using a bias tidal flow system with a filter. MDV, FMS, and LD were measured at 1.5 lb and 3.5 lb of applied force. A mathematical model was used to predict LD based on experimental measurements of MDV and FMS. Experimental BDP LD measurements for ABS, silicone, and polyurethane at 1.5 lb were 0.9 (0.6) μg, 2.4 (1.9) μg, and 19.3 (0.9) μg, respectively. At 3.5 lb, the respective LD was 10.0 (1.5) μg, 13.8 (1.4) μg, and 14.2 (0.9) μg. Parametric analysis with the mathematical model showed that differences in FMS between face models had a greater impact on LD than differences in MDV. The use of soft face models resulted in higher LD than hard face models, with a greater difference at 1.5 lb than at 3.5 lb. A lack of a FMS led to decreased dose consistency; therefore, a sealant should be used when measuring LD with a hard ABS or soft silicone face model at 1.5 lb of applied force or less.

  15. Continuous noninvasive ventilation delivered by a novel total face mask: a case series report.

    PubMed

    Belchior, Inês; Gonçalves, Miguel R; Winck, João Carlos

    2012-03-01

    Noninvasive ventilation (NIV) has been widely used to decrease the complications associated with tracheal intubation in mechanically ventilated patients. However, nasal ulcerations may occur when conventional masks are used for continuous ventilation. A total face mask, which has no contact with the more sensitive areas of the face, is a possible option. We describe 3 patients with acute respiratory failure due to amyotrophic lateral sclerosis, who developed nasal bridge skin necrosis during continuous NIV, and one patient with post-extubation respiratory failure due to a high spinal cord injury, who had facial trauma with contraindication for conventional mask use. The total face mask was very well tolerated by all the patients, and permitted safe and efficient continuous NIV for several days until the acute respiratory failure episode resolved. None of the patients required endotracheal intubation during the acute episode.

  16. Oral mask ventilation is more effective than face mask ventilation after nasal surgery.

    PubMed

    Yazicioğlu, Dilek; Baran, Ilkay; Uzumcugil, Filiz; Ozturk, Ibrahim; Utebey, Gulten; Sayın, M Murat

    2016-06-01

    To evaluate and compare the face mask (FM) and oral mask (OM) ventilation techniques during anesthesia emergence regarding tidal volume, leak volume, and difficult mask ventilation (DMV) incidence. Prospective, randomized, crossover study. Operating room, training and research hospital. American Society of Anesthesiologists physical status I and II adult patients scheduled for nasal surgery. Patients in group FM-OM received FM ventilation first, followed by OM ventilation, and patients in group OM-FM received OM ventilation first, followed by FM ventilation, with spontaneous ventilation after deep extubation. The FM ventilation was applied with the 1-handed EC-clamp technique. The OM was placed only over the mouth, and the 1-handed EC-clamp technique was used again. A child's size FM was used for the OM ventilation technique, the mask was rotated, and the inferior part of the mask was placed toward the nose. The leak volume (MVleak), mean airway pressure (Pmean), and expired tidal volume (TVe) were assessed with each mask technique for 3 consecutive breaths. A mask ventilation grade ≥3 was considered DMV. DMV occurred more frequently during FM ventilation (75% with FM vs 8% with OM). In the FM-first sequence, the mean TVe was 249±61mL with the FM and 455±35mL with the OM (P=.0001), whereas in the OM-first sequence, it was 276±81mL with the FM and 409±37mL with the OM (P=.0001). Regardless of the order used, the OM technique significantly decreased the MVleak and increased the TVe when compared to the FM technique. During anesthesia emergence after nasal surgery the OM may offer an effective ventilation method as it decreases the incidence of DMV and the gas leak around the mask and provides higher tidal volume delivery compared with FM ventilation. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Thin-plate spline analysis of the effects of face mask treatment in children with maxillary retrognathism.

    PubMed

    Chang, Jenny Zwei-Chieng; Liu, Pao-Hsin; Chen, Yi-Jane; Yao, Jane Chung-Chen; Chang, Hong-Po; Chang, Chih-Han; Chang, Frank Hsin-Fu

    2006-02-01

    Face mask therapy is indicated for growing patients who suffer from maxillary retrognathia. Most previous studies used conventional cephalometric analysis to evaluate the effects of face mask treatment. Cephalometric analysis has been shown to be insufficient for complex craniofacial configurations. The purpose of this study was to investigate changes in the craniofacial structure of children with maxillary retrognathism following face mask treatment by means of thin-plate spline analysis. Thirty children with skeletal Class III malocclusions who had been treated with face masks were compared with a group of 30 untreated gender-matched, age-matched, observation period-matched, and craniofacial configuration-matched subjects. Average geometries, scaled to an equivalent size, were generated by means of Procrustes analysis. Thin-plate spline analysis was then performed for localization of the shape changes. Face mask treatment induced a forward displacement of the maxilla, a counterclockwise rotation of the palatal plane, a horizontal compression of the anterior border of the symphysis and the condylar region, and a downward deformation of the menton. The cranial base exhibited a counterclockwise deformation as a whole. We conclude that thin-plate spline analysis is a valuable supplement to conventional cephalometric analysis.

  18. Face mask sampling for the detection of Mycobacterium tuberculosis in expelled aerosols.

    PubMed

    Williams, Caroline M L; Cheah, Eddy S G; Malkin, Joanne; Patel, Hemu; Otu, Jacob; Mlaga, Kodjovi; Sutherland, Jayne S; Antonio, Martin; Perera, Nelun; Woltmann, Gerrit; Haldar, Pranabashis; Garton, Natalie J; Barer, Michael R

    2014-01-01

    Although tuberculosis is transmitted by the airborne route, direct information on the natural output of bacilli into air by source cases is very limited. We sought to address this through sampling of expelled aerosols in face masks that were subsequently analyzed for mycobacterial contamination. In series 1, 17 smear microscopy positive patients wore standard surgical face masks once or twice for periods between 10 minutes and 5 hours; mycobacterial contamination was detected using a bacteriophage assay. In series 2, 19 patients with suspected tuberculosis were studied in Leicester UK and 10 patients with at least one positive smear were studied in The Gambia. These subjects wore one FFP30 mask modified to contain a gelatin filter for one hour; this was subsequently analyzed by the Xpert MTB/RIF system. In series 1, the bacteriophage assay detected live mycobacteria in 11/17 patients with wearing times between 10 and 120 minutes. Variation was seen in mask positivity and the level of contamination detected in multiple samples from the same patient. Two patients had non-tuberculous mycobacterial infections. In series 2, 13/20 patients with pulmonary tuberculosis produced positive masks and 0/9 patients with extrapulmonary or non-tuberculous diagnoses were mask positive. Overall, 65% of patients with confirmed pulmonary mycobacterial infection gave positive masks and this included 3/6 patients who received diagnostic bronchoalveolar lavages. Mask sampling provides a simple means of assessing mycobacterial output in non-sputum expectorant. The approach shows potential for application to the study of airborne transmission and to diagnosis.

  19. Face Mask Sampling for the Detection of Mycobacterium tuberculosis in Expelled Aerosols

    PubMed Central

    Malkin, Joanne; Patel, Hemu; Otu, Jacob; Mlaga, Kodjovi; Sutherland, Jayne S.; Antonio, Martin; Perera, Nelun; Woltmann, Gerrit; Haldar, Pranabashis; Garton, Natalie J.; Barer, Michael R.

    2014-01-01

    Background Although tuberculosis is transmitted by the airborne route, direct information on the natural output of bacilli into air by source cases is very limited. We sought to address this through sampling of expelled aerosols in face masks that were subsequently analyzed for mycobacterial contamination. Methods In series 1, 17 smear microscopy positive patients wore standard surgical face masks once or twice for periods between 10 minutes and 5 hours; mycobacterial contamination was detected using a bacteriophage assay. In series 2, 19 patients with suspected tuberculosis were studied in Leicester UK and 10 patients with at least one positive smear were studied in The Gambia. These subjects wore one FFP30 mask modified to contain a gelatin filter for one hour; this was subsequently analyzed by the Xpert MTB/RIF system. Results In series 1, the bacteriophage assay detected live mycobacteria in 11/17 patients with wearing times between 10 and 120 minutes. Variation was seen in mask positivity and the level of contamination detected in multiple samples from the same patient. Two patients had non-tuberculous mycobacterial infections. In series 2, 13/20 patients with pulmonary tuberculosis produced positive masks and 0/9 patients with extrapulmonary or non-tuberculous diagnoses were mask positive. Overall, 65% of patients with confirmed pulmonary mycobacterial infection gave positive masks and this included 3/6 patients who received diagnostic bronchoalveolar lavages. Conclusion Mask sampling provides a simple means of assessing mycobacterial output in non-sputum expectorant. The approach shows potential for application to the study of airborne transmission and to diagnosis. PMID:25122163

  20. SU-E-T-65: A Prospective Trial of Open Face Masks for Head and Neck Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wiant, D; Squire, S; Maurer, J

    Purpose: Open face head and neck masks allow for active patient monitoring during treatment and may reduced claustrophobia and anxiety compared to closed masks. The ability of open masks to limit intrafraction motion and to preserve the patient shape/position from simulation over protracted treatments should be considered. Methods: Thirty-two head and neck patients were prospectively randomized to treatment in a closed mask or a novel open face mask. All patients received daily volumetric imaging. The daily images were automatically rigidly registered to the planning CT’s offline using a commercial image processing tool. The shifts needed to optimize the registration, themore » mutual information coefficient (MI), and the Pearson correlation (PC) coefficients were recorded to evaluate shape preservation. The open group was set-up and monitored with surface imaging at treatment. The real time surface imaging information was recorded to evaluate intrafraction motion. Results: Sixteen patients were included in each group. Evaluations were made over a total of 984 fractions. The mean MI and PC showed significantly higher shape preservation for the open group than for the closed group (p = 0). The mean rotations for the open group were smaller or < 0.15° larger versus the closed group. The mean intrafraction motion for the open group was 0.93 +/−0.99 mm (2 SD). The maximum single fraction displacement was 3.2 mm. Fourteen of 16 patients showed no significant correlation of motion with fraction number (p > 0.05). Conclusion: The open masks preserved shape as well as the closed masks, and they limited motion to < 2 mm for 95% of the treated fractions. These results are consistent over treatment courses of up to 35 fractions. The open mask is suitable for treatment with or without active monitoring. This work was partially supported by Qfix.« less

  1. Suicidal nitrogen inhalation by use of scuba full-face diving mask.

    PubMed

    Straka, Lubomir; Novomesky, Frantisek; Gavel, Anton; Mlynar, Juraj; Hejna, Petr

    2013-09-01

    A 29-year-old man was found dead lying on the bed in a hotel room in a famous Slovak mountain resort. He had a full-face diving mask on his face, connected through a diving breath regulator to a valve of an industrial (nondiving) high-pressure tank containing pure 100% nitrogen. The breath regulator (open-circuit type) used allowed inhalation of nitrogen without addition of open air, and the full-face diving mask assured aspiration of the gas even during the time of unconsciousness. At autopsy, we found the typical signs of suffocation. Toxicological analysis revealed 94.7% content of nitrogen in alveolar air. Following the completion of the police investigation, the manner of death was classified as a suicide. Within the medico-legal literature, there has been only one similar case of suicidal nitrogen inhalation described. © 2013 American Academy of Forensic Sciences.

  2. Backward masked fearful faces enhance contralateral occipital cortical activity for visual targets within the spotlight of attention

    PubMed Central

    Reinke, Karen S.; LaMontagne, Pamela J.; Habib, Reza

    2011-01-01

    Spatial attention has been argued to be adaptive by enhancing the processing of visual stimuli within the ‘spotlight of attention’. We previously reported that crude threat cues (backward masked fearful faces) facilitate spatial attention through a network of brain regions consisting of the amygdala, anterior cingulate and contralateral visual cortex. However, results from previous functional magnetic resonance imaging (fMRI) dot-probe studies have been inconclusive regarding a fearful face-elicited contralateral modulation of visual targets. Here, we tested the hypothesis that the capture of spatial attention by crude threat cues would facilitate processing of subsequently presented visual stimuli within the masked fearful face-elicited ‘spotlight of attention’ in the contralateral visual cortex. Participants performed a backward masked fearful face dot-probe task while brain activity was measured with fMRI. Masked fearful face left visual field trials enhanced activity for spatially congruent targets in the right superior occipital gyrus, fusiform gyrus and lateral occipital complex, while masked fearful face right visual field trials enhanced activity in the left middle occipital gyrus. These data indicate that crude threat elicited spatial attention enhances the processing of subsequent visual stimuli in contralateral occipital cortex, which may occur by lowering neural activation thresholds in this retinotopic location. PMID:20702500

  3. Force-dependent static dead space of face masks used with holding chambers.

    PubMed

    Shah, Samir A; Berlinski, Ariel B; Rubin, Bruce K

    2006-02-01

    Pressurized metered-dose inhalers with valved holding chambers and masks are commonly used for aerosol delivery in children. Drug delivery can decrease when the dead-space volume (DSV) of the valved holding chamber is increased, but there are no published data evaluating force-dependent DSV among different masks. Seven masks were studied. Masks were sealed at the valved holding chamber end and filled with water to measure mask volume. To measure mask DSV we used a mannequin of 2-year-old-size face and we applied the mask with forces of 1.5, 3.5, and 7 pounds. Mask seal was determined by direct observation. Intra-brand analysis was done via analysis of variance. At 3.5 pounds of force, the DSV ranged from 29 mL to 100 mL, with 3 masks having DSV of < 50 mL. The remaining masks all had DSV > 60 mL. At 3.5 pounds of force, DSV percent of mask volume ranged from 33.7% (Aerochamber, p < 0.01 compared with other masks) to 100% (Pocket Chamber). DSV decreased with increasing force with most of the masks, and the slope of this line was inversely proportional to mask flexibility. Mask fit was 100% at 1.5 pounds of force only with the Aerochamber and Optichamber. Mask fit was poorest with the Vortex, Pocket Chamber, and BreatheRite masks. Rigid masks with large DSV might not be not suitable for use in children, especially if discomfort from the stiff mask makes its use less acceptable to the child.

  4. Marquardt's Phi mask: pitfalls of relying on fashion models and the golden ratio to describe a beautiful face.

    PubMed

    Holland, E

    2008-03-01

    Stephen Marquardt has derived a mask from the golden ratio that he claims represents the "ideal" facial archetype. Many have found his mask convincing, including cosmetic surgeons. However, Marquardt's mask is associated with numerous problems. The method used to examine goodness of fit with the proportions in the mask is faulty. The mask is ill-suited for non-European populations, especially sub-Saharan Africans and East Asians. The mask also appears to approximate the face shape of masculinized European women. Given that the general public strongly and overwhelmingly prefers above average facial femininity in women, white women seeking aesthetic facial surgery would be ill-advised to aim toward a better fit with Marquardt's mask. This article aims to show the proper way of assessing goodness of fit with Marquardt's mask, to address the shape of the mask as it pertains to masculinity-femininity, and to discuss the broader issue of an objective assessment of facial attractiveness. Generalized Procrustes analysis is used to show how goodness of fit with Marquardt's mask can be assessed. Thin-plate spline analysis is used to illustrate visually how sample faces, including northwestern European averages, differ from Marquardt's mask. Marquardt's mask best describes the facial proportions of masculinized white women as seen in fashion models. Marquardt's mask does not appear to describe "ideal" face shape even for white women because its proportions are inconsistent with the optimal preferences of most people, especially with regard to femininity.

  5. Standoff imaging of a masked human face using a 670 GHz high resolution radar

    NASA Astrophysics Data System (ADS)

    Kjellgren, Jan; Svedin, Jan; Cooper, Ken B.

    2011-11-01

    This paper presents an exploratory attempt to use high-resolution radar measurements for face identification in forensic applications. An imaging radar system developed by JPL was used to measure a human face at 670 GHz. Frontal views of the face were measured both with and without a ski mask at a range of 25 m. The realized spatial resolution was roughly 1 cm in all three dimensions. The surfaces of the ski mask and the face were detected by using the two dominating reflections from amplitude data. Various methods for visualization of these surfaces are presented. The possibility to use radar data to determine certain face distance measures between well-defined face landmarks, typically used for anthropometric statistics, was explored. The measures used here were face length, frontal breadth and interpupillary distance. In many cases the radar system seems to provide sufficient information to exclude an innocent subject from suspicion. For an accurate identification it is believed that a system must provide significantly more information.

  6. Neonatal mannequin comparison of the Upright self-inflating bag and snap-fit mask versus standard resuscitators and masks: leak, applied load and tidal volumes.

    PubMed

    Rafferty, Anthony Richard; Johnson, Lucy; Davis, Peter G; Dawson, Jennifer Anne; Thio, Marta; Owen, Louise S

    2017-11-30

    Neonatal mask ventilation is a difficult skill to acquire and maintain. Mask leak is common and can lead to ineffective ventilation. The aim of this study was to determine whether newly available neonatal self-inflating bags and masks could reduce mask leak without additional load being applied to the face. Forty operators delivered 1 min episodes of mask ventilation to a mannequin using the Laerdal Upright Resuscitator, a standard Laerdal infant resuscitator (Laerdal Medical) and a T-Piece Resuscitator (Neopuff), using both the Laerdal snap-fit face mask and the standard Laerdal size 0/1 face mask (equivalent sizes). Participants were asked to use pressure sufficient to achieve 'appropriate' chest rise. Leak, applied load, airway pressure and tidal volume were measured continuously. Participants were unaware that load was being recorded. There was no difference in mask leak between resuscitation devices. Leak was significantly lower when the snap-fit mask was used with all resuscitation devices, compared with the standard mask (14% vs 37% leak, P<0.01). The snap-fit mask was preferred by 83% of participants. The device-mask combinations had no significant effect on applied load. The Laerdal Upright Resuscitator resulted in similar leak to the other resuscitation devices studied, and did not exert additional load to the face and head. The snap-fit mask significantly reduced overall leak with all resuscitation devices and was the mask preferred by participants. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. Wearing face masks in public during the influenza season may reflect other positive hygiene practices in Japan.

    PubMed

    Wada, Koji; Oka-Ezoe, Kuniko; Smith, Derek R

    2012-12-10

    Although the wearing of face masks in public has not been recommended for preventing influenza, these devices are often worn in many Asian countries during the influenza season. In Japan, it is thought that such behavior may be an indicator of other positive hygiene practices. The aim of this study, therefore, was to determine if wearing a face mask in public is associated with other positive hygiene practices and health behaviors among Japanese adults. We initially recruited around 3,000 Japanese individuals ranging from 20 to 69 years of age who were registered with a web survey company. Participants were asked to recall their personal hygiene practices during the influenza season of the previous year. Logistic regression analysis was then used to examine the associations between wearing a face mask in public and personal hygiene practices and health behaviors. A total of 3,129 persons responded to the survey, among whom 38% reported that they had worn a face mask in public during the previous influenza season. Wearing a face mask in public was associated with various self-reported hygiene practices including: frequent hand washing (adjusted Odds Ratio [OR]: 1.67; 95% Confidence Interval [95%CI]: 1.34-1.96), occasional hand washing (OR: 1.43; 95%CI: 1.10-1.75), frequently avoiding crowds (OR: 1.85; 95%CI: 1.70-1.98), occasionally avoiding crowds (OR: 1.65; 95%CI: 1.53-1.76), frequent gargling (OR: 1.68; 95%CI: 1.51-1.84), occasional gargling (OR: 1.46; 95%CI: 1.29-1.62), regularly avoiding close contact with an infected person (OR: 1.50; 95%CI: 1.33-1.67), occasionally avoiding close contact with an infected person (OR: 1.31; 95%CI: 1.16-1.46), and being vaccinated of influenza in the last season (OR: 1.31; 95%CI: 1.17-1.45). Overall, this study suggests that wearing a face mask in public may be associated with other personal hygiene practices and health behaviors among Japanese adults. Rather than preventing influenza itself, face mask use might instead be a

  8. Influence of total face, facial and nasal masks on short-term adverse effects during noninvasive ventilation.

    PubMed

    Holanda, Marcelo Alcantara; Reis, Ricardo Coelho; Winkeler, Georgia Freire Paiva; Fortaleza, Simone Castelo Branco; Lima, José Wellington de Oliveira; Pereira, Eanes Delgado Barros

    2009-02-01

    Failure of noninvasive ventilation (NIV) has been associated with short-term adverse effects related to the use of masks. The aim of this study was to compare the incidence, type and intensity of adverse effects, as well as the comfort, of total face masks (TFMs), facial masks (FMs) and nasal masks (NMs) during NIV. This was a randomized crossover trial involving 24 healthy volunteers submitted to six sessions of NIV in bilevel positive airway pressure mode using the TFM, FM and NM masks at low and moderate-to-high pressure levels. A written questionnaire was applied in order to evaluate eleven specific adverse effects related to the use of the masks. Comfort was assessed using a visual analog scale. The CO2 exhaled into the ventilator circuit was measured between the mask and the exhalation port. The performance of the TFM was similar to that of the NM and FM in terms of comfort scores. Higher pressure levels reduced comfort and increased adverse effects, regardless of the mask type. When the TFM was used, there were fewer air leaks and less pain at the nose bridge, although there was greater oronasal dryness and claustrophobia. Air leaks were most pronounced when the FM was used. The partial pressure of exhaled CO2 entering the ventilator circuit was zero for the TFM. The short-term adverse effects caused by NIV interfaces are related to mask type and pressure settings. The TFM is a reliable alternative to the NM and FM. Rebreathing of CO2 from the circuit is less likely to occur when a TFM is used.

  9. Assessment of a respiratory face mask for capturing air pollutants and pathogens including human influenza and rhinoviruses.

    PubMed

    Zhou, S Steve; Lukula, Salimatu; Chiossone, Cory; Nims, Raymond W; Suchmann, Donna B; Ijaz, M Khalid

    2018-03-01

    Prevention of infection with airborne pathogens and exposure to airborne particulates and aerosols (environmental pollutants and allergens) can be facilitated through use of disposable face masks. The effectiveness of such masks for excluding pathogens and pollutants is dependent on the intrinsic ability of the masks to resist penetration by airborne contaminants. This study evaluated the relative contributions of a mask, valve, and Micro Ventilator on aerosol filtration efficiency of a new N95 respiratory face mask. The test mask was challenged, using standardized methods, with influenza A and rhinovirus type 14, bacteriophage ΦΧ174, Staphylococcus aureus ( S . aureus ), and model pollutants. The statistical significance of results obtained for different challenge microbial agents and for different mask configurations (masks with operational or nonoperational ventilation fans and masks with sealed Smart Valves) was assessed. The results demonstrate >99.7% efficiency of each test mask configuration for exclusion of influenza A virus, rhinovirus 14, and S . aureus and >99.3% efficiency for paraffin oil and sodium chloride (surrogates for PM 2.5 ). Statistically significant differences in effectiveness of the different mask configurations were not identified. The efficiencies of the masks for excluding smaller-size (i.e., rhinovirus and bacteriophage ΦΧ174) vs. larger-size microbial agents (influenza virus, S . aureus ) were not significantly different. The masks, with or without features intended for enhancing comfort, provide protection against both small- and large-size pathogens. Importantly, the mask appears to be highly efficient for filtration of pathogens, including influenza and rhinoviruses, as well as the fine particulates (PM 2.5 ) present in aerosols that represent a greater challenge for many types of dental and surgical masks. This renders this individual-use N95 respiratory mask an improvement over the former types of masks for protection against

  10. Cross sectional: perception of children from public and private schools regarding the esthetic impact of different types of face masks.

    PubMed

    Pithon, Matheus Melo; Ferraz, Caio Sousa; de Oliveira, Gabriel Couto; Dos Santos, Adrielle Mangabeira; Couto, Felipe Santos; da Silva Coqueiro, Raildo; Dos Santos, Rogério Lacerda

    2013-01-01

    The purpose was to evaluate the esthetic perception among children from public and private schools regarding the use of different types of face masks. Six different types of orthopedic face masks made from images of the same patient were evaluated. Initially, the images were standardized with the help of Adobe Photoshop software. The variable considered was type of mask: (A) Delaire with facebow; (B) Petit; (C) Delaire; (D)Turley; (E) Hickham; and (F) Sky Hook. The images were printed on photographic paper and incorporated into a specific personalized questionnaire that was distributed to 7- to 10-year-olds attending public and private schools (n=120). The data obtained were compared via chi-square, Fisher's exact tests, Mann-Whitney and Spearman's tests. The proportion of participants who chose image A as the best was significantly higher (P<.05) compared to the other masks. Images B and F were chosen as the worst, without a significant difference between them (P>.05). The mean scores between groups were not significantly correlated between private vs public schoolchildren (r=0.32) and between boys and girls (r=0.41). Delaire face mask with facebow was chosen as the most attractive, and the Petit and Sky Hook face masks were voted the least attractive.

  11. Assessment of a respiratory face mask for capturing air pollutants and pathogens including human influenza and rhinoviruses

    PubMed Central

    Zhou, S. Steve; Lukula, Salimatu; Chiossone, Cory; Nims, Raymond W.; Suchmann, Donna B.

    2018-01-01

    Background Prevention of infection with airborne pathogens and exposure to airborne particulates and aerosols (environmental pollutants and allergens) can be facilitated through use of disposable face masks. The effectiveness of such masks for excluding pathogens and pollutants is dependent on the intrinsic ability of the masks to resist penetration by airborne contaminants. This study evaluated the relative contributions of a mask, valve, and Micro Ventilator on aerosol filtration efficiency of a new N95 respiratory face mask. Methods The test mask was challenged, using standardized methods, with influenza A and rhinovirus type 14, bacteriophage ΦΧ174, Staphylococcus aureus (S. aureus), and model pollutants. The statistical significance of results obtained for different challenge microbial agents and for different mask configurations (masks with operational or nonoperational ventilation fans and masks with sealed Smart Valves) was assessed. Results The results demonstrate >99.7% efficiency of each test mask configuration for exclusion of influenza A virus, rhinovirus 14, and S. aureus and >99.3% efficiency for paraffin oil and sodium chloride (surrogates for PM2.5). Statistically significant differences in effectiveness of the different mask configurations were not identified. The efficiencies of the masks for excluding smaller-size (i.e., rhinovirus and bacteriophage ΦΧ174) vs. larger-size microbial agents (influenza virus, S. aureus) were not significantly different. Conclusions The masks, with or without features intended for enhancing comfort, provide protection against both small- and large-size pathogens. Importantly, the mask appears to be highly efficient for filtration of pathogens, including influenza and rhinoviruses, as well as the fine particulates (PM2.5) present in aerosols that represent a greater challenge for many types of dental and surgical masks. This renders this individual-use N95 respiratory mask an improvement over the former types of

  12. A pilot study on the use of geometrically accurate face models to replicate ex vivo N95 mask fit.

    PubMed

    Golshahi, Laleh; Telidetzki, Karla; King, Ben; Shaw, Diana; Finlay, Warren H

    2013-01-01

    To test the feasibility of replicating a face mask seal in vitro, we created 5 geometrically accurate reconstructions of the head and neck of an adult human subject using different materials. Three breathing patterns were simulated with each replica and an attached N95 mask. Quantitative fit testing on the subject and the replicas showed that none of the 5 isotropic materials used allowed duplication of the ex vivo mask seal for the specific mask-face combination studied. Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  13. Defect tolerant transmission lithography mask

    DOEpatents

    Vernon, Stephen P.

    2000-01-01

    A transmission lithography mask that utilizes a transparent substrate or a partially transparent membrane as the active region of the mask. A reflective single layer or multilayer coating is deposited on the membrane surface facing the illumination system. The coating is selectively patterned (removed) to form transmissive (bright) regions. Structural imperfections and defects in the coating have negligible effect on the aerial image of the mask master pattern since the coating is used to reflect radiation out of the entrance pupil of the imaging system. Similarly, structural imperfections in the clear regions of the membrane have little influence on the amplitude or phase of the transmitted electromagnetic fields. Since the mask "discards," rather than absorbs, unwanted radiation, it has reduced optical absorption and reduced thermal loading as compared to conventional designs. For EUV applications, the mask circumvents the phase defect problem, and is independent of the thermal load during exposure.

  14. A prospective evaluation of open face masks for head and neck radiation therapy.

    PubMed

    Wiant, David; Squire, Sarah; Liu, Han; Maurer, Jacqueline; Lane Hayes, T; Sintay, Benjamin

    Head and neck (HN) radiation therapy patients are typically immobilized with closed thermoplastic masks that cover the face and may cause discomfort. In this work, we examine the use of open masks for HN radiation therapy. Fifty HN patients were prospectively randomized into 2 groups (25 closed masks, 25 open masks). The open-mask group was monitored with surface imaging to evaluate intrafraction motion. Both groups underwent daily volumetric imaging. All daily images were rigidly registered to their respective planning images to evaluate spinal canal and mandible position as a check for interfraction posture change. Posture changes were determined by the amount the spinal canal and mandible contours from the planning images had to be expanded to cover the structures on each daily image set. The vector length (VL) of the intrafraction linear translations, spine, and mandible positions for each open-mask patient were checked for correlation with fraction number using the Pearson r value. All patients were given a weekly survey ranking anxiety and claustrophobia from 0 to 10 (0 = no issue, 10 = extreme issue). The mean VL for all open-mask patients was 0.9 ± 0.5 mm (1 standard deviation). Only 1 patient showed significant correlation between VL and fraction number. The mean contour expansions to cover the spine and mandible were 1.5 ± 0.9 mm and 1.8 ± 1.3 mm for the closed-mask group, and 1.6 ± 0.8 mm and 1.8 ± 1.1 mm for the open-mask group. Both groups showed similar behavior relative to fraction number. The mean anxiety and claustrophobia scores were 1.63 and 1.44 for the closed-mask group, and 0.81 and 0.63 for the open-mask group. The groups were not significantly different. Open masks provide comparable immobilization and posture preservation to closed masks for HN radiation therapy. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  15. Variations in backward masking with different masking stimuli: II. The effects of spatially quantised masks in the light of local contour interaction, interchannel inhibition, perceptual retouch, and substitution theories.

    PubMed

    Bachmann, Talis; Luiga, Iiris; Põder, Endel

    2005-01-01

    In part I we showed that with spatially non-overlapping targets and masks both local metacontrast-like interactions and attentional processes are involved in backward masking. In this second part we extend the strategy of varying the contents of masks to pattern masking where targets and masks overlap in space, in order to compare different masking theories. Images of human faces were backward-masked by three types of spatially quantised masks (the same faces as targets, faces different from targets, and Gaussian noise with power spectra typical for faces). Configural characteristics, rather than the spectral content of the mask, predicted the extent of masking at relatively long stimulus onset asynchronies (SOAs). This poses difficulties for the theory of transient-on-sustained inhibition as the principal mechanism of masking and also for local contour interaction being a decisive factor in pattern masking. The scale of quantisation had no effect on the masking capacity of noise masks and a strong effect on the capacity of different-face masks. Also, the decrease of configural masking with an increase in the coarseness of the quantisation of the mask highlights ambiguities inherent in the re-entrance-based substitution theory of masking. Different masking theories cannot solve the problems of masking separately. They should be combined in order to create a complex, yet comprehensible mode of interaction for the different mechanisms involved in visual backward masking.

  16. In Vitro Comparison of Aerosol Delivery Using Different Face Masks and Flow Rates With a High-Flow Humidity System.

    PubMed

    Lin, Hui-Ling; Harwood, Robert J; Fink, James B; Goodfellow, Lynda T; Ari, Arzu

    2015-09-01

    Aerosol drug delivery to infants and small children is influenced by many factors, such as types of interface, gas flows, and the designs of face masks. The purpose of this in vitro study was to evaluate aerosol delivery during administration of gas flows across the range used clinically with high-flow humidity systems using 2 aerosol masks. A spontaneous lung model was used to simulate an infant/young toddler up to 2 y of age and pediatric breathing patterns. Nebulized salbutamol by a vibrating mesh nebulizer positioned at the inlet of a high-flow humidification system at gas flows of 3, 6, and 12 L/min was delivered via pediatric face masks to a pediatric face mannequin attached to a filter. Aerosol particle size distribution exiting the vibrating mesh nebulizer and at the mask position distal to the heated humidifier with 3 flows was measured with a cascade impactor. Eluted drug from the filters and the impactor was analyzed with a spectrophotometer (n = 3). Statistical analysis was performed by analysis of variance with a significant level of P < .05. The inhaled mass was between 2.8% and 8.1% among all settings and was significantly lower at 12 L/min (P = .004) in the pediatric model. Drug delivery with pediatric breathing was greater than with infant breathing (P = .004). The particle size distribution of aerosol emitted from the nebulizer was larger than the heated humidified aerosol exiting the tubing (P = .002), with no difference between the 3 flows (P = .10). The flows of gas entering the mask and breathing patterns influence aerosol delivery, independent of the face mask used. Aerosol delivery through a high-flow humidification system via mask could be effective with both infant and pediatric breathing patterns. Copyright © 2015 by Daedalus Enterprises.

  17. Laser Doppler imaging of cutaneous blood flow through transparent face masks: a necessary preamble to computer-controlled rapid prototyping fabrication with submillimeter precision.

    PubMed

    Allely, Rebekah R; Van-Buendia, Lan B; Jeng, James C; White, Patricia; Wu, Jingshu; Niszczak, Jonathan; Jordan, Marion H

    2008-01-01

    A paradigm shift in management of postburn facial scarring is lurking "just beneath the waves" with the widespread availability of two recent technologies: precise three-dimensional scanning/digitizing of complex surfaces and computer-controlled rapid prototyping three-dimensional "printers". Laser Doppler imaging may be the sensible method to track the scar hyperemia that should form the basis of assessing progress and directing incremental changes in the digitized topographical face mask "prescription". The purpose of this study was to establish feasibility of detecting perfusion through transparent face masks using the Laser Doppler Imaging scanner. Laser Doppler images of perfusion were obtained at multiple facial regions on five uninjured staff members. Images were obtained without a mask, followed by images with a loose fitting mask with and without a silicone liner, and then with a tight fitting mask with and without a silicone liner. Right and left oblique images, in addition to the frontal images, were used to overcome unobtainable measurements at the extremes of face mask curvature. General linear model, mixed model, and t tests were used for data analysis. Three hundred seventy-five measurements were used for analysis, with a mean perfusion unit of 299 and pixel validity of 97%. The effect of face mask pressure with and without the silicone liner was readily quantified with significant changes in mean cutaneous blood flow (P < .5). High valid pixel rate laser Doppler imager flow data can be obtained through transparent face masks. Perfusion decreases with the application of pressure and with silicone. Every participant measured differently in perfusion units; however, consistent perfusion patterns in the face were observed.

  18. Backward Masking: Evidence of Reduced Subcortical Amygdala Engagement in Autism

    ERIC Educational Resources Information Center

    Hall, Geoffrey B. C.; West, C. Dianne; Szatmari, Peter

    2007-01-01

    Recent data suggest that subthreshold presentation of emotional information is relayed to the amygdala along subcortical pathways. We examined the effect of backward masked neutral and anxious faces on the social decisions of a group of high functioning children with autism ages 7-13 years and matched controls. Participants were asked to select…

  19. Testing the efficacy of homemade masks: would they protect in an influenza pandemic?

    PubMed

    Davies, Anna; Thompson, Katy-Anne; Giri, Karthika; Kafatos, George; Walker, Jimmy; Bennett, Allan

    2013-08-01

    This study examined homemade masks as an alternative to commercial face masks. Several household materials were evaluated for the capacity to block bacterial and viral aerosols. Twenty-one healthy volunteers made their own face masks from cotton t-shirts; the masks were then tested for fit. The number of microorganisms isolated from coughs of healthy volunteers wearing their homemade mask, a surgical mask, or no mask was compared using several air-sampling techniques. The median-fit factor of the homemade masks was one-half that of the surgical masks. Both masks significantly reduced the number of microorganisms expelled by volunteers, although the surgical mask was 3 times more effective in blocking transmission than the homemade mask. Our findings suggest that a homemade mask should only be considered as a last resort to prevent droplet transmission from infected individuals, but it would be better than no protection.

  20. Continuous positive airway pressure and ventilation are more effective with a nasal mask than a full face mask in unconscious subjects: a randomized controlled trial.

    PubMed

    Oto, Jun; Li, Qian; Kimball, William R; Wang, Jingping; Sabouri, Abdolnabi S; Harrell, Priscilla G; Kacmarek, Robert M; Jiang, Yandong

    2013-12-23

    Upper airway obstruction (UAO) is a major problem in unconscious subjects, making full face mask ventilation difficult. The mechanism of UAO in unconscious subjects shares many similarities with that of obstructive sleep apnea (OSA), especially the hypotonic upper airway seen during rapid eye movement sleep. Continuous positive airway pressure (CPAP) via nasal mask is more effective at maintaining airway patency than a full face mask in patients with OSA. We hypothesized that CPAP via nasal mask and ventilation (nCPAP) would be more effective than full face mask CPAP and ventilation (FmCPAP) for unconscious subjects, and we tested our hypothesis during induction of general anesthesia for elective surgery. In total, 73 adult subjects requiring general anesthesia were randomly assigned to one of four groups: nCPAP P0, nCPAP P5, FmCPAP P0, and FmCPAP P5, where P0 and P5 represent positive end-expiratory pressure (PEEP) 0 and 5 cm H2O applied prior to induction. After apnea, ventilation was initiated with pressure control ventilation at a peak inspiratory pressure over PEEP (PIP/PEEP) of 20/0, then 20/5, and finally 20/10 cm H2O, each applied for 1 min. At each pressure setting, expired tidal volume (Vte) was calculated by using a plethysmograph device. The rate of effective tidal volume (Vte > estimated anatomical dead space) was higher (87.9% vs. 21.9%; P<0.01) and the median Vte was larger (6.9 vs. 0 mL/kg; P<0.01) with nCPAP than with FmCPAP. Application of CPAP prior to induction of general anesthesia did not affect Vte in either approach (nCPAP pre- vs. post-; 7.9 vs. 5.8 mL/kg, P = 0.07) (FmCPAP pre- vs. post-; 0 vs. 0 mL/kg, P = 0.11). nCPAP produced more effective tidal volume than FmCPAP in unconscious subjects. ClinicalTrials.gov identifier: NCT01524614.

  1. Delivery of helium–oxygen mixture during spontaneous breathing: evaluation of three high-concentration face masks.

    PubMed

    Roche-Campo, Ferran; Vignaux, Laurence; Galia, Fabrice; Lyazidi, Aissam; Vargas, Frédéric; Texereau, Joëlle; Apiou-Sbirlea, Gabriela; Jolliet, Philippe; Brochard, Laurent

    2011-11-01

    To evaluate the efficacy of delivering a mixture of helium and oxygen gas (He–O2) in spontaneous ventilation. Three high oxygen flow reservoir masks were tested: the Heliox21, specifically designed for helium; the Hi-Ox80 mask, with an inspiratory and an expiratory valve; and a standard high-concentration face mask. This prospective randomized crossover study was performed in six healthy volunteers in a laboratory setting. Volunteers breathed a mixture of 78% He/22% O2 through each of the masks under two different breathing conditions (rest and hyperventilation: minute ventilation of 14.9 ± 6.1 and 26.7 ± 8.7 L min(−1), respectively) and four different He–O2 flow rates (7, 10, 12, and 15 L min(−1)). A nasopharyngeal catheter was used to estimate He pharyngeal concentration (Fp [He]) in the airways in order to determine the percentage of contamination with room air (% air cont) at end-expiration. Under all testing conditions, the Hi-Ox80 mask presented a significantly lower % air cont. During resting breathing pattern, a Fp [He] higher than 50% was achieved in 54% of the tests performed with the Hi-Ox80 mask compared to 29% for the Heliox21 mask and only 17% for the standard mask. At hyperventilation, a Fp [He] higher than 50% was achieved in 17% of the tests performed with the Hi-Ox mask compared to 4% for the other two masks. He–O2 administration via the usual high-concentration reservoir masks results in significant dilution by room air. The Hi-Ox80 mask minimized room air contamination and much more frequently achieved a pharyngeal He concentration higher than 50%.

  2. Maxillary Protraction With Intermaxillary Elastics to Miniplates Versus Bone-Anchored Face-Mask Therapy in Cleft Lip and Palate Patients.

    PubMed

    Jahanbin, Arezoo; Kazemian, Mozhgan; Eslami, Neda; Pouya, Iman Saeedi

    2016-07-01

    Cleft lip and palate patients usually have deficient maxilla due to postsurgical scars. The aim this study was to compare the effectiveness of miniplates-anchored face-mask therapy versus intermaxillary elastics to miniplates for maxillary traction in cleft lip and palate patients. This clinical trial included 11 prepubertal patients with cleft lip and palate. Initially, a w-arch expander was cemented and activated 3 mm per month to overcorrect the crossbite. Then, the patients were divided into 2 groups: mini-plate-anchored face-mask (n = 5): 2 miniplates were placed in the maxilla and the patients were instructed to wear a face-mask for 12 to 14 hours/per day. Intermaxillary elastics to miniplates (n = 6): 2 miniplates were inserted in the maxilla; 1 on each side and 2 miniplates were placed in the anterior mandible on both sides. Intermaxillary elastics with a force of 250 g per side were attached to the hooks. Cephalometric parameters before treatment (T1) and after achieving positive overjet (T2) were compared between the 2 groups. Fisher exact, paired, and independent t tests were used for statistical comparison. At T1 or T2 there was not a significant difference between the 2 groups in the skeletal, dental, and soft tissue variables. According to results of our preliminary study, intermaxillary elastics to miniplates might have a promising effect as an alternative for face mask therapy in maxillary protraction of cleft lip and palate patients.

  3. Particulate face masks for protection against airborne pathogens - one size does not fit all: an observational study.

    PubMed

    Winter, Susan; Thomas, Jane H; Stephens, Dianne P; Davis, Joshua S

    2010-03-01

    To determine the proportion of hospital staff who pass fit tests with each of three commonly used particulate face masks, and factors influencing preference and fit test results. Observational study. 50 healthy hospital staff volunteers in an 18-bed general intensive care unit in an Australian teaching hospital. Participants were administered a questionnaire about mask use and their preferred mask and underwent qualitative fit-testing with each of three different particulate masks: Kimberly-Clark Tecnol FluidShield N95 particulate filter respirator (KC), 3M Flat Fold 9320 particulate respirator and 3M 8822 particulate respirator with exhalation valve. Participants who failed fittesting were trained in correct mask donning, and fittesting was repeated. Proportion of participants who passed the fit test for each mask and the effect of training. The proportion of participants who passed a fit test was low for all three masks tested (KC, 16%; flat fold, 28%; and valved, 34%). Rates improved after training: the first mask tested fitted in 18% of participants pre-training and 40% post-training (P = 0.02). None of the masks fitted for 28% of participants. There were no significant predictors of fit-test results. A large proportion of individuals failed a fit test with any given mask, and we were not able to identify any factors that predicted mask fit in individuals. Training on mask use improved the rates of adequate fit. Hospitals should carry a range of P2 masks, and should conduct systematic P2 mask training and fit-testing programs for all staff potentially exposed to airborne pathogens.

  4. The Influence of Various Factors on High School Football Helmet Face Mask Removal: A Retrospective, Cross-Sectional Analysis

    PubMed Central

    Swartz, Erik E; Decoster, Laura C; Norkus, Susan A; Cappaert, Thomas A

    2007-01-01

    Context: Most research on face mask removal has been performed on unused equipment. Objective: To identify and compare factors that influence the condition of helmet components and their relationship to face mask removal. Design: A cross-sectional, retrospective study. Setting: Five athletic equipment reconditioning/recertification facilities. Participants: 2584 helmets from 46 high school football teams representing 5 geographic regions. Intervention(s): Helmet characteristics (brand, model, hardware components) were recorded. Helmets were mounted and face mask removal was attempted using a cordless screwdriver. The 2004 season profiles and weather histories were obtained for each high school. Main Outcome Measure(s): Success and failure (including reason) for removal of 4 screws from the face mask were noted. Failure rates among regions, teams, reconditioning year, and screw color (type) were compared. Weather histories were compared. We conducted a discriminant analysis to determine if weather variables, region, helmet brand and model, reconditioning year, and screw color could predict successful face mask removal. Metallurgic analysis of screw samples was performed. Results: All screws were successfully removed from 2165 (84%) helmets. At least 1 screw could not be removed from 419 (16%) helmets. Significant differences were found for mean screw failure per helmet among the 5 regions, with the Midwest having the lowest failure rate (0.08 ± 0.38) and the Southern (0.33 ± 0.72), the highest. Differences were found in screw failure rates among the 46 teams (F1,45 = 9.4, P < .01). Helmets with the longest interval since last reconditioning (3 years) had the highest failure rate, 0.47 ± 0.93. Differences in success rates were found among 4 screw types (χ21,4 = 647, P < .01), with silver screws having the lowest percentage of failures (3.4%). A discriminant analysis (Λ = .932, χ214,n=2584 = 175.34, P < .001) revealed screw type to be the strongest predictor of

  5. Adaptation to different noninvasive ventilation masks in critically ill patients*

    PubMed Central

    da Silva, Renata Matos; Timenetsky, Karina Tavares; Neves, Renata Cristina Miranda; Shigemichi, Liane Hirano; Kanda, Sandra Sayuri; Maekawa, Carla; Silva, Eliezer; Eid, Raquel Afonso Caserta

    2013-01-01

    OBJECTIVE: To identify which noninvasive ventilation (NIV) masks are most commonly used and the problems related to the adaptation to such masks in critically ill patients admitted to a hospital in the city of São Paulo, Brazil. METHODS: An observational study involving patients ≥ 18 years of age admitted to intensive care units and submitted to NIV. The reason for NIV use, type of mask, NIV regimen, adaptation to the mask, and reasons for non-adaptation to the mask were investigated. RESULTS: We evaluated 245 patients, with a median age of 82 years. Acute respiratory failure was the most common reason for NIV use (in 71.3%). Total face masks were the most commonly used (in 74.7%), followed by full face masks and near-total face masks (in 24.5% and 0.8%, respectively). Intermittent NIV was used in 82.4% of the patients. Adequate adaptation to the mask was found in 76% of the patients. Masks had to be replaced by another type of mask in 24% of the patients. Adequate adaptation to total face masks and full face masks was found in 75.5% and 80.0% of the patients, respectively. Non-adaptation occurred in the 2 patients using near-total facial masks. The most common reason for non-adaptation was the shape of the face, in 30.5% of the patients. CONCLUSIONS: In our sample, acute respiratory failure was the most common reason for NIV use, and total face masks were the most commonly used. The most common reason for non-adaptation to the mask was the shape of the face, which was resolved by changing the type of mask employed. PMID:24068269

  6. Adaptation to different noninvasive ventilation masks in critically ill patients.

    PubMed

    Silva, Renata Matos da; Timenetsky, Karina Tavares; Neves, Renata Cristina Miranda; Shigemichi, Liane Hirano; Kanda, Sandra Sayuri; Maekawa, Carla; Silva, Eliezer; Eid, Raquel Afonso Caserta

    2013-01-01

    To identify which noninvasive ventilation (NIV) masks are most commonly used and the problems related to the adaptation to such masks in critically ill patients admitted to a hospital in the city of São Paulo, Brazil. An observational study involving patients ≥ 18 years of age admitted to intensive care units and submitted to NIV. The reason for NIV use, type of mask, NIV regimen, adaptation to the mask, and reasons for non-adaptation to the mask were investigated. We evaluated 245 patients, with a median age of 82 years. Acute respiratory failure was the most common reason for NIV use (in 71.3%). Total face masks were the most commonly used (in 74.7%), followed by full face masks and near-total face masks (in 24.5% and 0.8%, respectively). Intermittent NIV was used in 82.4% of the patients. Adequate adaptation to the mask was found in 76% of the patients. Masks had to be replaced by another type of mask in 24% of the patients. Adequate adaptation to total face masks and full face masks was found in 75.5% and 80.0% of the patients, respectively. Non-adaptation occurred in the 2 patients using near-total facial masks. The most common reason for non-adaptation was the shape of the face, in 30.5% of the patients. In our sample, acute respiratory failure was the most common reason for NIV use, and total face masks were the most commonly used. The most common reason for non-adaptation to the mask was the shape of the face, which was resolved by changing the type of mask employed.

  7. Migration from full‐head mask to “open‐face” mask for immobilization of patients with head and neck cancer

    PubMed Central

    Lovelock, D. Michael; Mechalakos, James; Rao, Shyam; Della‐Biancia, Cesar; Amols, Howard; Lee, Nancy

    2013-01-01

    To provide an alternative device for immobilization of the head while easing claustrophobia and improving comfort, an “open‐face” thermoplastic mask was evaluated using video‐based optical surface imaging (OSI) and kilovoltage (kV) X‐ray radiography. A three‐point thermoplastic head mask with a precut opening and reinforced strips was developed. After molding, it provided sufficient visible facial area as the region of interest for OSI. Using real‐time OSI, the head motion of ten volunteers in the new mask was evaluated during mask locking and 15 minutes lying on the treatment couch. Using a nose mark with reference to room lasers, forced head movement in open‐face and full‐head masks (with a nose hole) was compared. Five patients with claustrophobia were immobilized with open‐face masks, set up using OSI and kV, and treated in 121 fractions, in which 61 fractions were monitored during treatment using real‐time OSI. With the open‐face mask, head motion was found to be 1.0 ± 0.6 mm and 0.4° ± 0.2° in volunteers during the experiment, and 0.8 ± 0.3 mm and 0.4° ± 0.2° in patients during treatment. These agree with patient motion calculated from pre‐/post‐treatment OSI and kV data using different anatomical landmarks. In volunteers, the head shift induced by mask‐locking was 2.3 ± 1.7 mm and 1.8° ± 0.6°, and the range of forced movements in the open‐face and full‐head masks were found to be similar. Most (80%) of the volunteers preferred the open‐face mask to the full‐head mask, while claustrophobic patients could only tolerate the open‐face mask. The open‐face mask is characterized for its immobilization capability and can immobilize patients sufficiently (< 2 mm) during radiotherapy. It provides a clinical solution to the immobilization of patients with head and neck (HN) cancer undergoing radiotherapy, and is particularly beneficial for claustrophobic patients. This new open‐face

  8. Oscillation transmission and volume delivery during face mask-delivered HFOV in infants: Bench and in vivo study.

    PubMed

    De Luca, Daniele; Costa, Roberta; Visconti, Federico; Piastra, Marco; Conti, Giorgio

    2016-07-01

    Noninvasive high frequency oscillatory ventilation (NHFOV) has not been studied beyond neonatal age and with interfaces other than nasal prongs. We set up a preliminary study to investigate feasibility, oscillation transmission, and volume delivery of face mask-delivered NHFOV in a bench model mimicking a normal 1-year infant without any lung disease and then in vivo in a series of infants with same characteristics. A mannequin with upper airways was connected to an electronic active lung simulator ventilated through NHFOV with varying parameters. Volume delivered by oscillations (oTv), oscillatory pressure ratio, and estimation of ventilation (DCO2) were measured at the lung simulator. Four infants were ventilated with face mask-delivered NHFOV for 2 hr and monitored with respiratory inductance plethismography. Vital parameters, oscillatory pressure ratio, oscillatory (RIPo), and spontaneous cage/abdomen displacement (RIPs) were recorded. There was a dampening of oscillation amplitude both on the bench model and in vivo: oscillatory pressure ratios at the mask were 80% and 17%, respectively. Significant correlations exist between oscillatory pressure ratio (only when this latter was <0.038) and oTv (r = 0.48; P < 0.001) or DCO2 (r = 0.47; P < 0.001). At multivariate analysis, oscillatory pressure ratio was a main determinant of oTv and DCO2. Oscillations were slightly visible on the chest in vivo and RIPo was about 5% of RIPs. NHFOV did not change vital parameters and did not cause discomfort. Face mask-delivered NHFOV is feasible in a model of 1-year infant. No major complications occurred in vivo. Oscillations are superimposed to the spontaneous breathing and are significantly dampened. Pediatr Pulmonol. Pediatr Pulmonol. 2016;51:705-712. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Face processing in different brain areas, and critical band masking.

    PubMed

    Rolls, Edmund T

    2008-09-01

    Neurophysiological evidence is described showing that some neurons in the macaque inferior temporal visual cortex have responses that are invariant with respect to the position, size, view, and spatial frequency of faces and objects, and that these neurons show rapid processing and rapid learning. Critical band spatial frequency masking is shown to be a property of these face-selective neurons and of the human visual perception of faces. Which face or object is present is encoded using a distributed representation in which each neuron conveys independent information in its firing rate, with little information evident in the relative time of firing of different neurons. This ensemble encoding has the advantages of maximizing the information in the representation useful for discrimination between stimuli using a simple weighted sum of the neuronal firing by the receiving neurons, generalization, and graceful degradation. These invariant representations are ideally suited to provide the inputs to brain regions such as the orbitofrontal cortex and amygdala that learn the reinforcement associations of an individual's face, for then the learning, and the appropriate social and emotional responses generalize to other views of the same face. A theory is described of how such invariant representations may be produced by self-organizing learning in a hierarchically organized set of visual cortical areas with convergent connectivity. The theory utilizes either temporal or spatial continuity with an associative synaptic modification rule. Another population of neurons in the cortex in the superior temporal sulcus encodes other aspects of faces such as face expression, eye-gaze, face view, and whether the head is moving. These neurons thus provide important additional inputs to parts of the brain such as the orbitofrontal cortex and amygdala that are involved in social communication and emotional behaviour. Outputs of these systems reach the amygdala, in which face

  10. Oxytocin attenuates neural reactivity to masked threat cues from the eyes.

    PubMed

    Kanat, Manuela; Heinrichs, Markus; Schwarzwald, Ralf; Domes, Gregor

    2015-01-01

    The neuropeptide oxytocin has recently been shown to modulate covert attention shifts to emotional face cues and to improve discrimination of masked facial emotions. These results suggest that oxytocin modulates facial emotion processing at early perceptual stages prior to full evaluation of the emotional expression. Here, we used functional magnetic resonance imaging to examine whether oxytocin alters neural responses to backwardly masked angry and happy faces while controlling for attention to the eye vs the mouth region. Intranasal oxytocin administration reduced amygdala reactivity to masked emotions when attending to salient facial features, ie, the eyes of angry faces and the mouth of happy faces. In addition, oxytocin decreased neural responses within the fusiform gyrus and brain stem areas, as well as functional coupling between the amygdala and the fusiform gyrus specifically for threat cues from the eyes. Effects of oxytocin on brain activity were not attributable to differences in behavioral performance, as oxytocin had no impact on mere emotion detection. Our results suggest that oxytocin attenuates neural correlates of early arousal by threat signals from the eye region. As reduced threat sensitivity may increase the likelihood of engaging in social interactions, our findings may have important implications for clinical states of social anxiety.

  11. Dissociative part-dependent biopsychosocial reactions to backward masked angry and neutral faces: An fMRI study of dissociative identity disorder.

    PubMed

    Schlumpf, Yolanda R; Nijenhuis, Ellert R S; Chalavi, Sima; Weder, Ekaterina V; Zimmermann, Eva; Luechinger, Roger; La Marca, Roberto; Reinders, A A T Simone; Jäncke, Lutz

    2013-01-01

    The Theory of Structural Dissociation of the Personality (TSDP) proposes that dissociative identity disorder (DID) patients are fixed in traumatic memories as "Emotional Parts" (EP), but mentally avoid these as "Apparently Normal Parts" of the personality (ANP). We tested the hypotheses that ANP and EP have different biopsychosocial reactions to subliminally presented angry and neutral faces, and that actors instructed and motivated to simulate ANP and EP react differently. Women with DID and matched healthy female actors (CON) were as ANP and EP (DIDanp, DIDep, CONanp, CONep) consecutively exposed to masked neutral and angry faces. Their brain activation was monitored using functional magnetic resonance imaging. The black-and-white dotted masks preceding and following the faces each had a centered colored dot, but in a different color. Participants were instructed to immediately press a button after a perceived color change. State anxiety was assessed after each run using the STAI-S. Final statistical analyses were conducted on 11 DID patients and 15 controls for differences in neural activity, and 13 DID patients and 15 controls for differences in behavior and psychometric measures. Differences between ANP and EP in DID patients and between DID and CON in the two dissociative parts of the personality were generally larger for neutral than for angry faces. The longest reaction times (RTs) existed for DIDep when exposed to neutral faces. Compared to DIDanp, DIDep was associated with more activation of the parahippocampal gyrus. Following neutral faces and compared to CONep, DIDep had more activation in the brainstem, face-sensitive regions, and motor-related areas. DIDanp showed a decreased activity all over the brain in the neutral and angry face condition. There were neither significant within differences nor significant between group differences in state anxiety. CON was not able to simulate genuine ANP and EP biopsychosocially. DID patients have dissociative

  12. Dissociative part-dependent biopsychosocial reactions to backward masked angry and neutral faces: An fMRI study of dissociative identity disorder☆

    PubMed Central

    Schlumpf, Yolanda R.; Nijenhuis, Ellert R.S.; Chalavi, Sima; Weder, Ekaterina V.; Zimmermann, Eva; Luechinger, Roger; La Marca, Roberto; Reinders, A.A.T. Simone; Jäncke, Lutz

    2013-01-01

    Objective The Theory of Structural Dissociation of the Personality (TSDP) proposes that dissociative identity disorder (DID) patients are fixed in traumatic memories as “Emotional Parts” (EP), but mentally avoid these as “Apparently Normal Parts” of the personality (ANP). We tested the hypotheses that ANP and EP have different biopsychosocial reactions to subliminally presented angry and neutral faces, and that actors instructed and motivated to simulate ANP and EP react differently. Methods Women with DID and matched healthy female actors (CON) were as ANP and EP (DIDanp, DIDep, CONanp, CONep) consecutively exposed to masked neutral and angry faces. Their brain activation was monitored using functional magnetic resonance imaging. The black-and-white dotted masks preceding and following the faces each had a centered colored dot, but in a different color. Participants were instructed to immediately press a button after a perceived color change. State anxiety was assessed after each run using the STAI-S. Final statistical analyses were conducted on 11 DID patients and 15 controls for differences in neural activity, and 13 DID patients and 15 controls for differences in behavior and psychometric measures. Results Differences between ANP and EP in DID patients and between DID and CON in the two dissociative parts of the personality were generally larger for neutral than for angry faces. The longest reaction times (RTs) existed for DIDep when exposed to neutral faces. Compared to DIDanp, DIDep was associated with more activation of the parahippocampal gyrus. Following neutral faces and compared to CONep, DIDep had more activation in the brainstem, face-sensitive regions, and motor-related areas. DIDanp showed a decreased activity all over the brain in the neutral and angry face condition. There were neither significant within differences nor significant between group differences in state anxiety. CON was not able to simulate genuine ANP and EP biopsychosocially

  13. 3D printed facial laser scans for the production of localised radiotherapy treatment masks - A case study.

    PubMed

    Briggs, Matthew; Clements, Helen; Wynne, Neil; Rennie, Allan; Kellett, Darren

    This study investigates the use of 3D printing for patients that require localised radiotherapy treatment to the face. The current process involves producing a lead mask in order to protect the healthy tissue from the effects of the radiotherapy. The mask is produced by applying a thermoplastic sheet to the patient's face and allowing to set hard. This can then be used as a mould to create a plaster impression of the patient's face. A sheet of lead is then hammered on to the plaster to create a bespoke fitted face mask. This process can be distressing for patients and can be problematic when the patient is required to remain motionless for a prolonged time while the thermoplastic sets. In this study, a 1:1 scale 3D print of a patient's face was generated using a laser scanner. The lead was hammered directly on to the surface of the 3D print in order to create a bespoke fitted treatment mask. This eliminated the thermoplastic moulding stage and significantly reduced the time needed for the patient to be in clinic. The higher definition impression of the the face resulted in a more accurate, better fitting treatment mask.

  14. Effect of mask dead space and occlusion of mask holes on delivery of nebulized albuterol.

    PubMed

    Berlinski, Ariel

    2014-08-01

    Infants and children with respiratory conditions are often prescribed bronchodilators. Face masks are used to facilitate the administration of nebulized therapy in patients unable to use a mouthpiece. Masks incorporate holes into their design, and their occlusion during aerosol delivery has been a common practice. Masks are available in different sizes and different dead volumes. The aim of this study was to compare the effect of different degrees of occlusion of the mask holes and different mask dead space on the amount of nebulized albuterol available at the mouth opening in a model of a spontaneously breathing child. A breathing simulator mimicking infant (tidal volume [VT] = 50 mL, breathing frequency = 30 breaths/min, inspiratory-expiratory ratio [I:E] = 1:3), child (VT = 155 mL, breathing frequency = 25 breaths/min, I:E = 1:2), and adult (VT = 500 mL, breathing frequency = 15 breaths/min, I:E = 1:2) breathing patterns was connected to a collection filter hidden behind a face plate. A pediatric size mask and an adult size mask connected to a continuous output jet nebulizer were sealed to the face plate. Three nebulizers were loaded with albuterol sulfate (2.5 mg/3 mL) and operated with 6 L/min compressed air for 5 min. Experiments were repeated with different degrees of occlusion (0%, 50%, and 90%). Albuterol was extracted from the filter and measured with a spectrophotometer at 276 nm. Occlusion of the holes in the large mask did not increase the amount of albuterol in any of the breathing patterns. The amount of albuterol captured at the mouth opening did not change when the small mask was switched to the large mask, except with the breathing pattern of a child, and when the holes in the mask were 50% occluded (P = .02). Neither decreasing the dead space of the mask nor occluding the mask holes increased the amount of nebulized albuterol captured at the mouth opening.

  15. Masking reduces orientation selectivity in rat visual cortex

    PubMed Central

    Alwis, Dasuni S.; Richards, Katrina L.

    2016-01-01

    In visual masking the perception of a target stimulus is impaired by a preceding (forward) or succeeding (backward) mask stimulus. The illusion is of interest because it allows uncoupling of the physical stimulus, its neuronal representation, and its perception. To understand the neuronal correlates of masking, we examined how masks affected the neuronal responses to oriented target stimuli in the primary visual cortex (V1) of anesthetized rats (n = 37). Target stimuli were circular gratings with 12 orientations; mask stimuli were plaids created as a binarized sum of all possible target orientations. Spatially, masks were presented either overlapping or surrounding the target. Temporally, targets and masks were presented for 33 ms, but the stimulus onset asynchrony (SOA) of their relative appearance was varied. For the first time, we examine how spatially overlapping and center-surround masking affect orientation discriminability (rather than visibility) in V1. Regardless of the spatial or temporal arrangement of stimuli, the greatest reductions in firing rate and orientation selectivity occurred for the shortest SOAs. Interestingly, analyses conducted separately for transient and sustained target response components showed that changes in orientation selectivity do not always coincide with changes in firing rate. Given the near-instantaneous reductions observed in orientation selectivity even when target and mask do not spatially overlap, we suggest that monotonic visual masking is explained by a combination of neural integration and lateral inhibition. PMID:27535373

  16. Face mask removal is safer than helmet removal for emergent airway access in American football.

    PubMed

    Swartz, Erik E; Mihalik, Jason P; Beltz, Nora M; Day, Molly A; Decoster, Laura C

    2014-06-01

    In cases of possible cervical spine injury, medical professionals must be prepared to achieve rapid airway access while concurrently restricting cervical spine motion. Face mask removal (FMR), rather than helmet removal (HR), is recommended to achieve this. However, no studies have been reported that compare FMR directly with HR. The purpose of this study was to compare motion, time, and perceived difficulty in two commonly used American football helmets between FMR and HR techniques, and when helmet air bladders were deflated before HR compared with inflated scenarios. The study incorporated a repeated measures design and was performed in a controlled laboratory setting. Participants included 22 certified athletic trainers (15 men and seven women; mean age, 33.9±10.5 years; mean experience, 11.4±10.0 years; mean height, 172±9.4 cm; mean mass, 76.7±14.9 kg). All participants were free from upper extremity or central nervous system pathology for 6 months and provided informed consent. Dependent variables included head excursion in degrees (computed by subtracting the minimum position from the maximum position) in each of the three planes (sagittal, frontal, transverse), time to complete the required task, and ratings of perceived exertion. To address our study purposes, we used two-by-two repeated-measures analysis of variance (removal technique×helmet type, helmet type×deflation status) for each dependent variable. Independent variables consisted of removal technique (FMR and HR), helmet type (Riddell Revolution IQ [RIQ] and VSR4), and helmet deflation status (deflated [D], inflated, [I]). After familiarization, participants conducted two successful trials for each of six conditions in random order (RIQ-FMR, VSR4-FMR, RIQ-HR-D, VSR4-HR-D, RIQ-HR-I, and VSR4-HR-I). Face masks, helmets, and shoulder pads were removed from a live model wearing a properly fitted helmet and shoulder pads. The participant and an investigator stabilized the model's head. A six

  17. Attentional effects of masked famous faces (but not names) and subjective evaluations of a target person.

    PubMed

    Stone, Anna

    2011-04-01

    Two experiments are reported using a 1986 version of the dot-probe paradigm of MacLeod, Mathews, and Tata, in which the masked subliminal faces of famous persons were differentially associated with attention depending on participants' attitudes toward the famous person. There was attentional avoidance of the faces of persons invoking high disgust (Exp. 1, n=20) or dislike (Exp. 2) but attentional orientation toward the faces of persons invoking low disgust or liking. In Exp. 2 (n=28), this effect was apparent for the faces but not the names of famous persons, despite evidence that the famous names were recognised without awareness. The aversion of attention from faces, but not the names of famous persons who are regarded in a negative light but who are not particularly threatening, may suggest an automatic tendency to avoid making eye contact with an undesirable person thereby avoiding unwanted social interaction.

  18. Design of a noninvasive face mask for ocular occlusion in rats and assessment in a visual discrimination paradigm.

    PubMed

    Hager, Audrey M; Dringenberg, Hans C

    2012-12-01

    The rat visual system is structured such that the large (>90 %) majority of retinal ganglion axons reach the contralateral lateral geniculate nucleus (LGN) and visual cortex (V1). This anatomical design allows for the relatively selective activation of one cerebral hemisphere under monocular viewing conditions. Here, we describe the design of a harness and face mask allowing simple and noninvasive monocular occlusion in rats. The harness is constructed from synthetic fiber (shoelace-type material) and fits around the girth region and neck, allowing for easy adjustments to fit rats of various weights. The face mask consists of soft rubber material that is attached to the harness by Velcro strips. Eyeholes in the mask can be covered by additional Velcro patches to occlude either one or both eyes. Rats readily adapt to wearing the device, allowing behavioral testing under different types of viewing conditions. We show that rats successfully acquire a water-maze-based visual discrimination task under monocular viewing conditions. Following task acquisition, interocular transfer was assessed. Performance with the previously occluded, "untrained" eye was impaired, suggesting that training effects were partially confined to one cerebral hemisphere. The method described herein provides a simple and noninvasive means to restrict visual input for studies of visual processing and learning in various rodent species.

  19. Effect of Noninvasive Ventilation Delivered by Helmet vs Face Mask on the Rate of Endotracheal Intubation in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial.

    PubMed

    Patel, Bhakti K; Wolfe, Krysta S; Pohlman, Anne S; Hall, Jesse B; Kress, John P

    2016-06-14

    Noninvasive ventilation (NIV) with a face mask is relatively ineffective at preventing endotracheal intubation in patients with acute respiratory distress syndrome (ARDS). Delivery of NIV with a helmet may be a superior strategy for these patients. To determine whether NIV delivered by helmet improves intubation rate among patients with ARDS. Single-center randomized clinical trial of 83 patients with ARDS requiring NIV delivered by face mask for at least 8 hours while in the medical intensive care unit at the University of Chicago between October 3, 2012, through September 21, 2015. Patients were randomly assigned to continue face mask NIV or switch to a helmet for NIV support for a planned enrollment of 206 patients (103 patients per group). The helmet is a transparent hood that covers the entire head of the patient and has a rubber collar neck seal. Early trial termination resulted in 44 patients randomized to the helmet group and 39 to the face mask group. The primary outcome was the proportion of patients who required endotracheal intubation. Secondary outcomes included 28-day invasive ventilator-free days (ie, days alive without mechanical ventilation), duration of ICU and hospital length of stay, and hospital and 90-day mortality. Eighty-three patients (45% women; median age, 59 years; median Acute Physiology and Chronic Health Evaluation [APACHE] II score, 26) were included in the analysis after the trial was stopped early based on predefined criteria for efficacy. The intubation rate was 61.5% (n = 24) for the face mask group and 18.2% (n = 8) for the helmet group (absolute difference, -43.3%; 95% CI, -62.4% to -24.3%; P < .001). The number of ventilator-free days was significantly higher in the helmet group (28 vs 12.5, P < .001). At 90 days, 15 patients (34.1%) in the helmet group died compared with 22 patients (56.4%) in the face mask group (absolute difference, -22.3%; 95% CI, -43.3 to -1.4; P = .02). Adverse events included 3

  20. A novel thermal face recognition approach using face pattern words

    NASA Astrophysics Data System (ADS)

    Zheng, Yufeng

    2010-04-01

    A reliable thermal face recognition system can enhance the national security applications such as prevention against terrorism, surveillance, monitoring and tracking, especially at nighttime. The system can be applied at airports, customs or high-alert facilities (e.g., nuclear power plant) for 24 hours a day. In this paper, we propose a novel face recognition approach utilizing thermal (long wave infrared) face images that can automatically identify a subject at both daytime and nighttime. With a properly acquired thermal image (as a query image) in monitoring zone, the following processes will be employed: normalization and denoising, face detection, face alignment, face masking, Gabor wavelet transform, face pattern words (FPWs) creation, face identification by similarity measure (Hamming distance). If eyeglasses are present on a subject's face, an eyeglasses mask will be automatically extracted from the querying face image, and then masked with all comparing FPWs (no more transforms). A high identification rate (97.44% with Top-1 match) has been achieved upon our preliminary face dataset (of 39 subjects) from the proposed approach regardless operating time and glasses-wearing condition.e

  1. 21 CFR 868.5570 - Nonrebreathing mask.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nonrebreathing mask. 868.5570 Section 868.5570...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5570 Nonrebreathing mask. (a) Identification. A nonrebreathing mask is a device fitting over a patient's face to administer oxygen. It utilizes...

  2. Noninvasive CPAP with face mask: comparison among new air-entrainment masks and the Boussignac valve.

    PubMed

    Mistraletti, Giovanni; Giacomini, Matteo; Sabbatini, Giovanni; Pinciroli, Riccardo; Mantovani, Elena S; Umbrello, Michele; Palmisano, Debora; Formenti, Paolo; Destrebecq, Anne L L; Iapichino, Gaetano

    2013-02-01

    The performances of 2 noninvasive CPAP systems (high flow and low flow air-entrainment masks) were compared to the Boussignac valve in 3 different scenarios. Scenario 1: pneumatic lung simulator with a tachypnea pattern (tidal volume 800 mL at 40 breaths/min). Scenario 2: Ten healthy subjects studied during tidal breaths and tachypnea. Scenario 3: Twenty ICU subjects enrolled for a noninvasive CPAP session. Differences between set and effective CPAP level and F(IO(2)), as well as the lowest airway pressure and the pressure swing around the imposed CPAP level, were analyzed. The lowest airway pressure and swing were correlated to the pressure-time product (area of the airway pressure curve below the CPAP level) measured with the simulator. P(aO(2)) was a subject's further performance index. Lung simulator: Boussignac F(IO(2)) was 0.54, even if supplied with pure oxygen. The air-entrainment masks had higher swing than the Boussignac (P = .007). Pressure-time product correlated better with pressure swing (Spearman correlation coefficient [ρ] = 0.97) than with lowest airway pressure (ρ = 0.92). In healthy subjects, the high-flow air-entrainment mask showed lower difference between set and effective F(IO(2)) (P < .001), and lowest airway pressure (P < .001), compared to the Boussignac valve. In all measurements the Boussignac valve showed higher than imposed CPAP level (P < .001). In ICU subjects the high-flow mask had lower swing than the Boussignac valve (P = .03) with similar P(aO(2)) increase. High-flow air-entrainment mask showed the best performance in human subjects. During high flow demand, the Boussignac valve delivered lower than expected F(IO(2)) and showed higher dynamic hyper-pressurization than the air-entrainment masks. © 2013 Daedalus Enterprises.

  3. Reduced mortality among young endangered masked bobwhite quail fed oxytetracycline-supplemented diets

    USGS Publications Warehouse

    Serafin, J.A.

    1982-01-01

    Two experiments were conducted to examine the effect of oxytetracycline-supplemented diets on mortality of young endangered masked bobwhite quail (Colinus virginianus ridgwayi). Inclusion of oxytetracycline at 200 g per ton in the feed for 6 weeks resulted in a marked, significant reduction in mortality of young masked bobwhite quail raised in captivity. Including the antibiotic in feed during the first week of life reduced mortality as effectively as feeding it for a longer period.

  4. What's in a mask? Information masking with forward and backward visual masks.

    PubMed

    Davis, Chris; Kim, Jeesun

    2011-10-01

    Three experiments tested how the physical format and information content of forward and backward masks affected the extent of visual pattern masking. This involved using different types of forward and backward masks with target discrimination measured by percentage correct in the first experiment (with a fixed target duration) and by an adaptive threshold procedure in the last two. The rationale behind the manipulation of the content of the masks stemmed from masking theories emphasizing attentional and/or conceptual factors rather than visual ones. Experiment 1 used word masks and showed that masking was reduced (a masking reduction effect) when the forward and backward masks were the same word (although in different case) compared to when the masks were different words. Experiment 2 tested the extent to which a reduction in masking might occur due to the physical similarity between the forward and backward masks by comparing the effect of the same content of the masks in the same versus different case. The result showed a significant reduction in masking for same content masks but no significant effect of case. The last experiment examined whether the reduction in masking effect would be observed with nonword masks--that is, having no high-level representation. No reduction in masking was found from same compared to different nonword masks (Experiment 3). These results support the view that the conscious perception of a rapidly displayed target stimulus is in part determined by high-level perceptual/cognitive factors concerned with masking stimulus grouping and attention.

  5. The Noh mask effect: vertical viewpoint dependence of facial expression perception.

    PubMed Central

    Lyons, M J; Campbell, R; Plante, A; Coleman, M; Kamachi, M; Akamatsu, S

    2000-01-01

    Full-face masks, worn by skilled actors in the Noh tradition, can induce a variety of perceived expressions with changes in head orientation. Out-of-plane rotation of the head changes the two-dimensional image characteristics of the face which viewers may misinterpret as non-rigid changes due to muscle action. Three experiments with Japanese and British viewers explored this effect. Experiment 1 confirmed a systematic relationship between vertical angle of view of a Noh mask and judged affect. A forward tilted mask was more often judged happy, and one backward tilted more often judged sad. This effect was moderated by culture. Japanese viewers ascribed happiness to the mask at greater degrees of backward tilt with a reversal towards sadness at extreme forward angles. Cropping the facial image of chin and upper head contour reduced the forward-tilt reversal. Finally, the relationship between head tilt and affect was replicated with a laser-scanned human face image, but with no cultural effect. Vertical orientation of the head changes the apparent disposition of facial features and viewers respond systematically to these changes. Culture moderates this effect, and we discuss how perceptual strategies for ascribing expression to familiar and unfamiliar images may account for the differences. PMID:11413638

  6. Comparison of Aerosol Delivery by Face Mask and Tracheostomy Collar.

    PubMed

    Bugis, Alaa A; Sheard, Meryl M; Fink, James B; Harwood, Robert J; Ari, Arzu

    2015-09-01

    The purpose of this study was to compare the performance of a tracheostomy collar, Wright mask, and aerosol mask attached to a jet nebulizer in facilitating aerosolized medication delivery to the lungs. We also compared albuterol delivery with open versus closed fenestration and determined the effect of inspiratory-expiratory ratio (I:E) on aerosol delivery. Albuterol (2.5 mg/3 mL) was administered to an in vitro model consisting of an adult teaching mannequin extrathoracic and upper airway with stoma intubated with an 8-mm fenestrated tracheostomy tube. The cuff was deflated. A collecting filter at the level of the bronchi was connected to a breathing simulator at a tidal volume of 400 mL, breathing frequency of 20 breaths/min, and I:E of 2:1 and 1:2. A jet nebulizer was operated with O2 at 8 L/min. Each interface was tested in triplicate. The flow was discontinued at the end of nebulization. For each test, the nebulizer was attached to a tracheostomy collar with the fenestration open or closed, a Wright mask, or an aerosol mask. Drug was analyzed by spectrophotometry (276 nm). A paired t test and analysis of variance were performed (P < .05). The mean ± SD percent albuterol dose delivered distal to the bronchi was greater with the tracheostomy collar with a closed fenestration (9.4 ± 1.5%) compared with an open fenestration (7.0 ± 0.8%). The doses delivered with the Wright mask (4.1 ± 0.6%) and aerosol mask (3.5 ± 0.04%) were both less than with the tracheostomy collar under either condition (P < .05). Increasing the I:E from 1:2 to 2:1 increased aerosol delivery by 2.5-4%, with significance for the tracheostomy collar with an open fenestration (11.6 ± 1.4%), Wright mask (7.2 ± 0.6%), and aerosol mask (6.1 ± 0.5%). In an adult tracheostomy model, the tracheostomy collar delivered more aerosol to the bronchi than the Wright or aerosol mask. An I:E of 2:1 caused greater aerosol deposition compared with an I:E of 1:2. During aerosol administration via a

  7. Reinforced Masks for Ion Plating of Solar Cells

    NASA Technical Reports Server (NTRS)

    Conley, W. R.; Swick, E. G.; Volkers, J. C.

    1987-01-01

    Proposed mask for ion plating of surface electrodes on silicon solar cells reinforced to hold shape better during handling. Fabrication process for improved mask similar to conventional mask. Additional cuts and bends made in wide diametral strip to form bridges between pairs of mask fingers facing each other across this strip. Bridges high enough not to act as masks so entire strip area plated.

  8. An optimized OPC and MDP flow for reducing mask write time and mask cost

    NASA Astrophysics Data System (ADS)

    Yang, Ellyn; Li, Cheng He; Park, Se Jin; Zhu, Yu; Guo, Eric

    2010-09-01

    In the process of optical proximity correction, layout edge or fragment is migrating to proper position in order to minimize edge placement error (EPE). During this fragment migration, several factors other than EPE can be also taken into account as a part of cost function for optimal fragment displacement. Several factors are devised in favor of OPC stability, which can accommodate room for high mask error enhancement factor (MEEF), lack of process window, catastrophic pattern failure such as pinch/bridge and improper fragmentation. As technology node becomes finer, there happens conflict between OPC accuracy and stability. Especially for metal layers, OPC has focused on the stability by loss of accurate OPC results. On this purpose, several techniques have been introduced, which are target smoothing, process window aware OPC, model-based retargeting and adaptive OPC. By utilizing those techniques, OPC enables more stabilized patterning, instead of realizing design target exactly on wafer. Inevitably, post-OPC layouts become more complicated because those techniques invoke additional edge, or fragments prior to correction or during OPC iteration. As a result, jogs of post OPC layer can be dramatically increased, which results in huge number of shot count after data fracturing. In other words, there is trade-off relationship between data complexity and various methods for OPC stability. In this paper, those relationships have been investigated with respect to several technology nodes. The mask shot count reduction is achieved by reducing the number of jogs with which EPE difference are within pre-specified value. The effect of jog smoothing on OPC output - in view of OPC performance and mask data preparation - was studied quantitatively for respective technology nodes.

  9. SU-D-BRA-02: Motion Assessment During Open Face Mask SRS Using CBCT and Surface Monitoring

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Williams, BB; Fox, CJ; Hartford, AC

    Purpose: To assess the robustness of immobilization using open-face mask technology for linac-based stereotactic radiosurgery (SRS) with multiple non-coplanar arcs via repeated CBCT acquisition, with comparison to contemporaneous optical surface tracking data. Methods: 25 patients were treated in open faced masks with cranial SRS using 3–4 non-coplanar arcs. Repeated CBCT imaging was performed to verify the maintenance of proper patient positioning during treatment. Initial patient positioning was performed based on prescribed shifts and optical surface tracking. Positioning refinements employed rigid 3D-matching of the planning CT and CBCT images and were implemented via automated 6DOF couch control. CBCT imaging was repeatedmore » following the treatment of all non-transverse beams with associated couch kicks. Detected patient translations and rotations were recorded and automatically corrected. Optical surface tracking was applied throughout the treatments to monitor motion, and this contemporaneous patient positioning data was recorded to compare against CBCT data and 6DOF couch adjustments. Results: Initial patient positions were refined on average by translations of 3±1mm and rotations of ±0.9-degrees. Optical surface tracking corroborated couch corrections to within 1±1mm and ±0.4-degrees. Following treatment of the transverse and subsequent superior-oblique beam, average translations of 0.6±0.4mm and rotations of ±0.4-degrees were reported via CBCT, with optical surface tracking in agreement to within 1.1±0.6mm and ±0.6-degrees. Following treatment of the third beam, CBCT indicated additional translations of 0.4±0.2mm and rotations of ±0.3-degrees. Cumulative couch corrections resulted in 0.7 ± 0.4mm average magnitude translations and rotations of ±0.4-degrees. Conclusion: Based on CBCT measurements of patients during SRS, the open face mask maintained patient positioning to within 1.5mm and 1-degree with >95% confidence. Patient positioning

  10. Superior Recognition Performance for Happy Masked and Unmasked Faces in Both Younger and Older Adults

    PubMed Central

    Svärd, Joakim; Wiens, Stefan; Fischer, Håkan

    2012-01-01

    In the aging literature it has been shown that even though emotion recognition performance decreases with age, the decrease is less for happiness than other facial expressions. Studies in younger adults have also revealed that happy faces are more strongly attended to and better recognized than other emotional facial expressions. Thus, there might be a more age independent happy face advantage in facial expression recognition. By using a backward masking paradigm and varying stimulus onset asynchronies (17–267 ms) the temporal development of a happy face advantage, on a continuum from low to high levels of visibility, was examined in younger and older adults. Results showed that across age groups, recognition performance for happy faces was better than for neutral and fearful faces at durations longer than 50 ms. Importantly, the results showed a happy face advantage already during early processing of emotional faces in both younger and older adults. This advantage is discussed in terms of processing of salient perceptual features and elaborative processing of the happy face. We also investigate the combined effect of age and neuroticism on emotional face processing. The rationale was previous findings of age-related differences in physiological arousal to emotional pictures and a relation between arousal and neuroticism. Across all durations, there was an interaction between age and neuroticism, showing that being high in neuroticism might be disadvantageous for younger, but not older adults’ emotion recognition performance during arousal enhancing tasks. These results indicate that there is a relation between aging, neuroticism, and performance, potentially related to physiological arousal. PMID:23226135

  11. Thin-plate spline analysis of treatment effects of rapid maxillary expansion and face mask therapy in early Class III malocclusions.

    PubMed

    Baccetti, T; Franchi, L; McNamara, J A

    1999-06-01

    An effective morphometric method (thin-plate spline analysis) was applied to evaluate shape changes in the craniofacial configuration of a sample of 23 children with Class III malocclusions in the early mixed dentition treated with rapid maxillary expansion and face mask therapy, and compared with a sample of 17 children with untreated Class III malocclusions. Significant treatment-induced changes involved both the maxilla and the mandible. Major deformations consisted of forward displacement of the maxillary complex from the pterygoid region and of anterior morphogenetic rotation of the mandible, due to a significant upward and forward direction of growth of the mandibular condyle. Significant differences in size changes due to reduced increments in mandibular dimensions were associated with significant shape changes in the treated group.

  12. Successful removal of football helmet face-mask clips after 1 season of use.

    PubMed

    Scibek, Jason S; Gatti, Joseph M; McKenzie, Jennifer I

    2012-01-01

    Whereas many researchers have assessed the ability to remove loop straps in traditional face-mask attachment systems after at least 1 season of use, research in which the effectiveness of the Riddell Quick Release (QR) Face Guard Attachment System clip after 1 season has been assessed is limited. To examine the success rate of removing the QR clips after 1 season of use at the Football Championship Subdivision level. We hypothesized that 1 season of use would negatively affect the removal rate of the QR clip but repeated clip-removal trials would improve the removal rate. Retrospective, quasi-experimental design. Controlled laboratory study. Sixty-three football helmets from a National Collegiate Athletic Association Division I university located in western Pennsylvania used during the 2008 season were tested. Three certified athletic trainers (2 men, 1 woman; age = 31.3 ± 3.06 years, time certified = 9.42 ± 2.65 years) attempted to remove the QR clips from each helmet with the tool provided by the manufacturer. Helmets then were reassembled to allow each athletic trainer to attempt clip removal. The dependent variables were total left clips removed (TCR-L), total right clips removed (TCR-R), and total clips removed (TCR). Success rate of clip removal (SRCR) also was assessed. Percentages for TCR-L, TCR-R, and TCR were 100% (189 of 189), 96.30% (182 of 189), and 98.15% (371 of 378), respectively. A paired-samples t test revealed a difference between TCR-R and TCR-L (t(188) = 2.689, P = .008, μ(d) = 0.037, 95% confidence interval [CI] = 0.064, 0.010). The percentage for SRCR was 96.30% (n = 182), whereas SRCR percentages for trials 1, 2, and 3 were 95.24% (n = 60), 98.41% (n = 62), and 95.24% (n = 60), respectively, and did not represent a difference (F(2,186) = 0.588, P = .56, 95% (CI) = 0.94, 0.99). Our results indicated favorable and consistent success rates for QR clip removal after 1 season of use. Whereas the QR clip is an advancement in face-mask

  13. Initial stabilisation of preterm infants: a new resuscitation system with low imposed work of breathing for use with face mask or nasal prongs.

    PubMed

    Donaldsson, Snorri; Drevhammar, Thomas; Taittonen, Leena; Klemming, Stina; Jonsson, Baldvin

    2017-05-01

    T-piece resuscitation systems are pressure unstable and have high imposed work of breathing (iWOB). Pressure stable respiratory support with low iWOB might improve outcome. We have developed a new resuscitation system that can be used with nasal prongs or face mask. The aim of the study was to describe the in vitro performance of the new system and to perform a clinical feasibility trial of initial stabilisation of preterm infants. A mechanical lung model was used to determine iWOB at increasing levels of continuous positive airway pressure (CPAP). The feasibility trial included 36 infants (27-34 weeks of gestation), who were randomised into three groups (T-piece, new system with face mask or new system with prongs). Collected data included problems with usage, safety, time to stable breathing, need for positive pressure ventilation and intubation. In the mechanical lung model, the new system reduced iWOB with 91.5% (mask) and 86.6% (medium prongs) compared with Neopuff (4 cm CPAP, p<0.001). Informed consent was obtained from 45 patients, 39 were randomised and 36 needed support. Randomisation resulted in an imbalance: The group of new system infants had lower gestational age compared with the T-piece group. Thirteen patients needed positive pressure ventilation (median 20 cm H 2 O). One infant was intubated. The study did not reveal problems with the equipment or safety. Compared with T-piece systems, the new system had a marked reduction in iWOB in bench tests. The feasibility trial did not reveal problems with usability or safety. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  14. Protection by face masks against influenza A(H1N1)pdm09 virus on trans-Pacific passenger aircraft, 2009.

    PubMed

    Zhang, Lijie; Peng, Zhibin; Ou, Jianming; Zeng, Guang; Fontaine, Robert E; Liu, Mingbin; Cui, Fuqiang; Hong, Rongtao; Zhou, Hang; Huai, Yang; Chuang, Shuk-Kwan; Leung, Yiu-Hong; Feng, Yunxia; Luo, Yuan; Shen, Tao; Zhu, Bao-Ping; Widdowson, Marc-Alain; Yu, Hongjie

    2013-01-01

    In response to several influenza A(H1N1)pdm09 infections that developed in passengers after they traveled on the same 2 flights from New York, New York, USA, to Hong Kong, China, to Fuzhou, China, we assessed transmission of influenza A(H1N1)pdm09 virus on these flights. We defined a case of infection as onset of fever and respiratory symptoms and detection of virus by PCR in a passenger or crew member of either flight. Illness developed only in passengers who traveled on the New York to Hong Kong flight. We compared exposures of 9 case-passengers with those of 32 asymptomatic control-passengers. None of the 9 case-passengers, compared with 47% (15/32) of control-passengers, wore a face mask for the entire flight (odds ratio 0, 95% CI 0-0.71). The source case-passenger was not identified. Wearing a face mask was a protective factor against influenza infection. We recommend a more comprehensive intervention study to accurately estimate this effect.

  15. Protection by Face Masks against Influenza A(H1N1)pdm09 Virus on Trans-Pacific Passenger Aircraft, 2009

    PubMed Central

    Zhang, Lijie; Peng, Zhibin; Ou, Jianming; Zeng, Guang; Fontaine, Robert E.; Liu, Mingbin; Cui, Fuqiang; Hong, Rongtao; Zhou, Hang; Huai, Yang; Chuang, Shuk-Kwan; Leung, Yiu-Hong; Feng, Yunxia; Luo, Yuan; Shen, Tao; Zhu, Bao-Ping; Widdowson, Marc-Alain

    2013-01-01

    In response to several influenza A(H1N1)pdm09 infections that developed in passengers after they traveled on the same 2 flights from New York, New York, USA, to Hong Kong, China, to Fuzhou, China, we assessed transmission of influenza A(H1N1)pdm09 virus on these flights. We defined a case of infection as onset of fever and respiratory symptoms and detection of virus by PCR in a passenger or crew member of either flight. Illness developed only in passengers who traveled on the New York to Hong Kong flight. We compared exposures of 9 case-passengers with those of 32 asymptomatic control-passengers. None of the 9 case-passengers, compared with 47% (15/32) of control-passengers, wore a face mask for the entire flight (odds ratio 0, 95% CI 0–0.71). The source case-passenger was not identified. Wearing a face mask was a protective factor against influenza infection. We recommend a more comprehensive intervention study to accurately estimate this effect. PMID:23968983

  16. Successful Removal of Football Helmet Face-Mask Clips After 1 Season of Use

    PubMed Central

    Scibek, Jason S.; Gatti, Joseph M.; McKenzie, Jennifer I.

    2012-01-01

    Context Whereas many researchers have assessed the ability to remove loop straps in traditional face-mask attachment systems after at least 1 season of use, research in which the effectiveness of the Riddell Quick Release (QR) Face Guard Attachment System clip after 1 season has been assessed is limited. Objective To examine the success rate of removing the QR clips after 1 season of use at the Football Championship Subdivision level. We hypothesized that 1 season of use would negatively affect the removal rate of the QR clip but repeated clip-removal trials would improve the removal rate. Design Retrospective, quasi-experimental design. Setting Controlled laboratory study. Patients or Other Participants Sixty-three football helmets from a National Collegiate Athletic Association Division I university located in western Pennsylvania used during the 2008 season were tested. Intervention(s) Three certified athletic trainers (2 men, 1 woman; age = 31.3 ± 3.06 years, time certified = 9.42 ± 2.65 years) attempted to remove the QR clips from each helmet with the tool provided by the manufacturer. Helmets then were reassembled to allow each athletic trainer to attempt clip removal. Main Outcome Measure(s) The dependent variables were total left clips removed (TCR-L), total right clips removed (TCR-R), and total clips removed (TCR). Success rate of clip removal (SRCR) also was assessed. Results Percentages for TCR-L, TCR-R, and TCR were 100% (189 of 189), 96.30% (182 of 189), and 98.15% (371 of 378), respectively. A paired-samples t test revealed a difference between TCR-R and TCR-L (t188 = −2.689, P = .008, μd = 0.037, 95% confidence interval [CI] = −0.064, −0.010). The percentage for SRCR was 96.30% (n = 182), whereas SRCR percentages for trials 1, 2, and 3 were 95.24% (n = 60), 98.41% (n = 62), and 95.24% (n = 60), respectively, and did not represent a difference (F2,186 = 0.588, P = .56, 95% CI = 0.94, 0.99). Conclusions Our results indicated favorable and

  17. Subliminal Face Emotion Processing: A Comparison of Fearful and Disgusted Faces.

    PubMed

    Khalid, Shah; Ansorge, Ulrich

    2017-01-01

    Prior research has provided evidence for (1) subcortical processing of subliminal facial expressions of emotion and (2) for the emotion-specificity of these processes. Here, we investigated if this is also true for the processing of the subliminal facial display of disgust. In Experiment 1, we used differently filtered masked prime faces portraying emotionally neutral or disgusted expressions presented prior to clearly visible target faces to test if the masked primes exerted an influence on target processing nonetheless. Whereas we found evidence for subliminal face congruence or priming effects, in particular, reverse priming by low spatial frequencies disgusted face primes, we did not find any support for a subcortical origin of the effect. In Experiment 2, we compared the influence of subliminal disgusted faces with that of subliminal fearful faces and demonstrated a behavioral performance difference between the two, pointing to an emotion-specific processing of the disgusted facial expressions. In both experiments, we also tested for the dependence of the subliminal emotional face processing on spatial attention - with mixed results, suggesting an attention-independence in Experiment 1 but not in Experiment 2 -, and we found perfect masking of the face primes - that is, proof of the subliminality of the prime faces. Based on our findings, we speculate that subliminal facial expressions of disgust could afford easy avoidance of these faces. This could be a unique effect of disgusted faces as compared to other emotional facial displays, at least under the conditions studied here.

  18. Developmental Conductive Hearing Loss Reduces Modulation Masking Release

    PubMed Central

    Chen, Yi-Wen; Sanes, Dan H.

    2016-01-01

    Hearing-impaired individuals experience difficulties in detecting or understanding speech, especially in background sounds within the same frequency range. However, normally hearing (NH) human listeners experience less difficulty detecting a target tone in background noise when the envelope of that noise is temporally gated (modulated) than when that envelope is flat across time (unmodulated). This perceptual benefit is called modulation masking release (MMR). When flanking masker energy is added well outside the frequency band of the target, and comodulated with the original modulated masker, detection thresholds improve further (MMR+). In contrast, if the flanking masker is antimodulated with the original masker, thresholds worsen (MMR−). These interactions across disparate frequency ranges are thought to require central nervous system (CNS) processing. Therefore, we explored the effect of developmental conductive hearing loss (CHL) in gerbils on MMR characteristics, as a test for putative CNS mechanisms. The detection thresholds of NH gerbils were lower in modulated noise, when compared with unmodulated noise. The addition of a comodulated flanker further improved performance, whereas an antimodulated flanker worsened performance. However, for CHL-reared gerbils, all three forms of masking release were reduced when compared with NH animals. These results suggest that developmental CHL impairs both within- and across-frequency processing and provide behavioral evidence that CNS mechanisms are affected by a peripheral hearing impairment. PMID:28215119

  19. More Realistic Face Model Surface Improves Relevance of Pediatric In-Vitro Aerosol Studies.

    PubMed

    Amirav, Israel; Halamish, Asaf; Gorenberg, Miguel; Omar, Hamza; Newhouse, Michael T

    2015-01-01

    Various hard face models are commonly used to evaluate the efficiency of aerosol face masks. Softer more realistic "face" surface materials, like skin, deform upon mask application and should provide more relevant in-vitro tests. Studies that simultaneously take into consideration many of the factors characteristic of the in vivo face are lacking. These include airways, various application forces, comparison of various devices, comparison with a hard-surface model and use of a more representative model face based on large numbers of actual faces. To compare mask to "face" seal and aerosol delivery of two pediatric masks using a soft vs. a hard, appropriately representative, pediatric face model under various applied forces. Two identical face models and upper airways replicas were constructed, the only difference being the suppleness and compressibility of the surface layer of the "face." Integrity of the seal and aerosol delivery of two different masks [AeroChamber (AC) and SootherMask (SM)] were compared using a breath simulator, filter collection and realistic applied forces. The soft "face" significantly increased the delivery efficiency and the sealing characteristics of both masks. Aerosol delivery with the soft "face" was significantly greater for the SM compared to the AC (p< 0.01). No statistically significant difference between the two masks was observed with the hard "face." The material and pliability of the model "face" surface has a significant influence on both the seal and delivery efficiency of face masks. This finding should be taken into account during in-vitro aerosol studies.

  20. Lateralization of kin recognition signals in the human face

    PubMed Central

    Dal Martello, Maria F.; Maloney, Laurence T.

    2010-01-01

    When human subjects view photographs of faces, their judgments of identity, gender, emotion, age, and attractiveness depend more on one side of the face than the other. We report an experiment testing whether allocentric kin recognition (the ability to judge the degree of kinship between individuals other than the observer) is also lateralized. One hundred and twenty-four observers judged whether or not pairs of children were biological siblings by looking at photographs of their faces. In three separate conditions, (1) the right hemi-face was masked, (2) the left hemi-face was masked, or (3) the face was fully visible. The d′ measures for the masked left hemi-face and masked right hemi-face were 1.024 and 1.004, respectively (no significant difference), and the d′ measure for the unmasked face was 1.079, not significantly greater than that for either of the masked conditions. We conclude, first, that there is no superiority of one or the other side of the observed face in kin recognition, second, that the information present in the left and right hemi-faces relevant to recognizing kin is completely redundant, and last that symmetry cues are not used for kin recognition. PMID:20884584

  1. Subliminal Face Emotion Processing: A Comparison of Fearful and Disgusted Faces

    PubMed Central

    Khalid, Shah; Ansorge, Ulrich

    2017-01-01

    Prior research has provided evidence for (1) subcortical processing of subliminal facial expressions of emotion and (2) for the emotion-specificity of these processes. Here, we investigated if this is also true for the processing of the subliminal facial display of disgust. In Experiment 1, we used differently filtered masked prime faces portraying emotionally neutral or disgusted expressions presented prior to clearly visible target faces to test if the masked primes exerted an influence on target processing nonetheless. Whereas we found evidence for subliminal face congruence or priming effects, in particular, reverse priming by low spatial frequencies disgusted face primes, we did not find any support for a subcortical origin of the effect. In Experiment 2, we compared the influence of subliminal disgusted faces with that of subliminal fearful faces and demonstrated a behavioral performance difference between the two, pointing to an emotion-specific processing of the disgusted facial expressions. In both experiments, we also tested for the dependence of the subliminal emotional face processing on spatial attention – with mixed results, suggesting an attention-independence in Experiment 1 but not in Experiment 2 –, and we found perfect masking of the face primes – that is, proof of the subliminality of the prime faces. Based on our findings, we speculate that subliminal facial expressions of disgust could afford easy avoidance of these faces. This could be a unique effect of disgusted faces as compared to other emotional facial displays, at least under the conditions studied here. PMID:28680413

  2. Optimization of optical proximity correction to reduce mask write time using genetic algorithm

    NASA Astrophysics Data System (ADS)

    Dick, Gregory J.; Cao, Liang; Asthana, Abhishek; Cheng, Jing; Power, David N.

    2018-03-01

    The ever increasing pattern densities and design complexities make the tuning of optical proximity correction (OPC) recipes very challenging. One known method for tuning is genetic algorithm (GA). Previously GA has been demonstrated to fine tune OPC recipes in order to achieve better results for possible 1D and 2D geometric concerns like bridging and pinching. This method, however, did not take into account the impact of excess segmentation on downstream operations like fracturing and mask writing. This paper introduces a general methodology to significantly reduce the number of excess edges in the OPC output, thus reducing the number of flashes generated at fracture and subsequently the write time at mask build. GA is used to reduce the degree of unwarranted segmentation while ensuring good OPC quality. An Objective Function (OF) is utilized to ensure quality convergence and process-variation (PV) plus an additional weighed factor to reduce clustered edge count. The technique is applied to 14nm metal layer OPC recipes in order to identify excess segmentation and to produce a modified recipe that significantly reduces these segments. OPC output file sizes is shown to be reduced by 15% or more and overall edge count is shown to be reduced by 10% or more. At the same time overall quality of the OPC recipe is shown to be maintained via OPC Verification (OPCV) results.

  3. Efficacy of a new device to optimize positive pressure ventilation via face mask in edentulous patients: a randomized trial.

    PubMed

    Niño, Maria C; Pauwels, Andres; Raffan, Fernando; Arango, Enrique; Romero, David J; Benitez, Daniel

    2017-04-01

    Mask ventilation is routinely performed during anesthesia. Under some circumstances, it might be difficult to perform, such as in edentulous patients, due to inadequate mask seal. We developed a new device called NIPARA and studied its use For ventilation optimization in edentulous patients. This randomized controlled trial included edentulous adults who had no other predictors of difficult airway, scheduled to undergo general anesthesia. Patients were assigned either to the NIPARA device group or to the control group (oral airway only). The primary outcomes were peak inspiratory pressure and tidal volume values of the first 14 breaths. The secondary outcome was the incidence of complications. Data from 37 patients were collected during a one-year period (twenty in the NIPARA device group and 17 in the control group). The difference in mean PIP was not statistically significant. The tidal volume was 1.5 times greater in the NIPARA group than in the control group. One patient from the intervention group had minimal oral trauma. In the administration of face mask ventilation, NIPARA is an effective device that significantly improves the tidal volume administered in edentulous patients.

  4. A respiratory mask for resting and exercising dogs.

    PubMed

    Stavert, D M; Reischl, P; O'Loughlin, B J

    1982-02-01

    A respiratory face mask has been developed for use with unsedated beagles trained to run on a treadmill. The latex rubber mask, shaped to fit the animal's muzzle, incorporates two modified, commercially available, pulmonary valves for separating inspiratory and expiratory flows. The mask has a dead space of 30 cm3 and a flow resistance below 1 cmH2O . 1(-1) . s. The flexible mask is used to measure breath-by-breath respiratory variables over extended periods of time during rest and exercise.

  5. Lung function after cold-water dives with a standard scuba regulator or full-face-mask during wintertime.

    PubMed

    Uhlig, Florian; Muth, Claus-Martin; Tetzlaff, Kay; Koch, Andreas; Leberle, Richard; Georgieff, Michael; Winkler, Bernd E

    2014-06-01

    Full-face-masks (FFM) prevent the diver's face from cold and can support nasal breathing underwater. The aim of the study was to evaluate the effect of the use of FFMs on lung function and wellbeing. Twenty-one, healthy, non-asthmatic divers performed two cold-water dives (4⁰C, 25 min, 10 metres' depth) - one with a FFM and the other with a standard scuba regulator (SSR). Spirometry was performed before and after each dive and well-being and cold sensation were assessed after the dives. Significant decreases in forced vital capacity (FVC), forced expiratory volume in one second (FEV₁) and midexpiratory flow at 75% of FVC (MEF₇₅) occurred after both FFM and SSR dives. Changes in FVC and FEV₁ did not differ significantly between FFM and SSR dives. However, the mid-expiratory flows measured at 50% and 25% of FVC (MEF₅₀ and MEF₂₅) were significantly lower 10 minutes after the FFM dive compared to 10 minutes after the SSR dive. The wellbeing and cold sensation of the divers were significantly improved with FFM dives compared to SSR dives. Cold-water dives during wintertime can be associated with airway narrowing. During cold-water dives, the use of a FFM appears to reduce the cold sensation and enhance the well-being of the divers. However, a FFM does not appear to prevent airway narrowing in healthy, non-asthmatic subjects.

  6. Neural circuitry of masked emotional face processing in youth with bipolar disorder, severe mood dysregulation, and healthy volunteers.

    PubMed

    Thomas, Laura A; Brotman, Melissa A; Bones, Brian L; Chen, Gang; Rosen, Brooke H; Pine, Daniel S; Leibenluft, Ellen

    2014-04-01

    Youth with bipolar disorder (BD) and those with severe, non-episodic irritability (severe mood dysregulation, SMD) show face-emotion labeling deficits. These groups differ from healthy volunteers (HV) in neural responses to emotional faces. It is unknown whether awareness is required to elicit these differences. We compared activation in BD (N=20), SMD (N=18), and HV (N=22) during "Aware" and "Non-aware" priming of shapes by emotional faces. Subjects rated how much they liked the shape. In aware, a face (angry, fearful, happy, neutral, blank oval) appeared (187 ms) before the shape. In non-aware, a face appeared (17 ms), followed by a mask (170 ms), and shape. A Diagnosis-by-Awareness-by-Emotion ANOVA was not significant. There were significant Diagnosis-by-Awareness interactions in occipital regions. BD and SMD showed increased activity for non-aware vs. aware; HV showed the reverse pattern. When subjects viewed angry or neutral faces, there were Emotion-by-Diagnosis interactions in face-emotion processing regions, including the L precentral gyrus, R posterior cingulate, R superior temporal gyrus, R middle occipital gyrus, and L medial frontal gyrus. Regardless of awareness, BD and SMD differ in activation patterns from HV and each other in multiple brain regions, suggesting that BD and SMD are distinct developmental mood disorders. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. EUV mask manufacturing readiness in the merchant mask industry

    NASA Astrophysics Data System (ADS)

    Green, Michael; Choi, Yohan; Ham, Young; Kamberian, Henry; Progler, Chris; Tseng, Shih-En; Chiou, Tsann-Bim; Miyazaki, Junji; Lammers, Ad; Chen, Alek

    2017-10-01

    As nodes progress into the 7nm and below regime, extreme ultraviolet lithography (EUVL) becomes critical for all industry participants interested in remaining at the leading edge. One key cost driver for EUV in the supply chain is the reflective EUV mask. As of today, the relatively few end users of EUV consist primarily of integrated device manufactures (IDMs) and foundries that have internal (captive) mask manufacturing capability. At the same time, strong and early participation in EUV by the merchant mask industry should bring value to these chip makers, aiding the wide-scale adoption of EUV in the future. For this, merchants need access to high quality, representative test vehicles to develop and validate their own processes. This business circumstance provides the motivation for merchants to form Joint Development Partnerships (JDPs) with IDMs, foundries, Original Equipment Manufacturers (OEMs) and other members of the EUV supplier ecosystem that leverage complementary strengths. In this paper, we will show how, through a collaborative supplier JDP model between a merchant and OEM, a novel, test chip driven strategy is applied to guide and validate mask level process development. We demonstrate how an EUV test vehicle (TV) is generated for mask process characterization in advance of receiving chip maker-specific designs. We utilize the TV to carry out mask process "stress testing" to define process boundary conditions which can be used to create Mask Rule Check (MRC) rules as well as serve as baseline conditions for future process improvement. We utilize Advanced Mask Characterization (AMC) techniques to understand process capability on designs of varying complexity that include EUV OPC models with and without sub-resolution assist features (SRAFs). Through these collaborations, we demonstrate ways to develop EUV processes and reduce implementation risks for eventual mass production. By reducing these risks, we hope to expand access to EUV mask capability for

  8. Influence of Temporal Expectations on Response Priming by Subliminal Faces

    PubMed Central

    Guex, Raphael; Vuilleumier, Patrik

    2016-01-01

    Unconscious processes are often assumed immune from attention influence. Recent behavioral studies suggest however that the processing of subliminal information can be influenced by temporal attention. To examine the neural mechanisms underlying these effects, we used a stringent masking paradigm together with fMRI to investigate how temporal attention modulates the processing of unseen (masked) faces. Participants performed a gender decision task on a visible neutral target face, preceded by a masked prime face that could vary in gender (same or different than target) and emotion expression (neutral or fearful). We manipulated temporal attention by instructing participants to expect targets to appear either early or late during the stimulus sequence. Orienting temporal attention to subliminal primes influenced response priming by masked faces, even when gender was incongruent. In addition, gender-congruent primes facilitated responses regardless of attention while gender-incongruent primes reduced accuracy when attended. Emotion produced no differential effects. At the neural level, incongruent and temporally unexpected primes increased brain response in regions of the fronto-parietal attention network, reflecting greater recruitment of executive control and reorienting processes. Congruent and expected primes produced higher activations in fusiform cortex, presumably reflecting facilitation of perceptual processing. These results indicate that temporal attention can influence subliminal processing of face features, and thus facilitate information integration according to task-relevance regardless of conscious awareness. They also suggest that task-congruent information between prime and target may facilitate response priming even when temporal attention is not selectively oriented to the prime onset time. PMID:27764124

  9. Influence of Temporal Expectations on Response Priming by Subliminal Faces.

    PubMed

    Pichon, Swann; Guex, Raphael; Vuilleumier, Patrik

    2016-01-01

    Unconscious processes are often assumed immune from attention influence. Recent behavioral studies suggest however that the processing of subliminal information can be influenced by temporal attention. To examine the neural mechanisms underlying these effects, we used a stringent masking paradigm together with fMRI to investigate how temporal attention modulates the processing of unseen (masked) faces. Participants performed a gender decision task on a visible neutral target face, preceded by a masked prime face that could vary in gender (same or different than target) and emotion expression (neutral or fearful). We manipulated temporal attention by instructing participants to expect targets to appear either early or late during the stimulus sequence. Orienting temporal attention to subliminal primes influenced response priming by masked faces, even when gender was incongruent. In addition, gender-congruent primes facilitated responses regardless of attention while gender-incongruent primes reduced accuracy when attended. Emotion produced no differential effects. At the neural level, incongruent and temporally unexpected primes increased brain response in regions of the fronto-parietal attention network, reflecting greater recruitment of executive control and reorienting processes. Congruent and expected primes produced higher activations in fusiform cortex, presumably reflecting facilitation of perceptual processing. These results indicate that temporal attention can influence subliminal processing of face features, and thus facilitate information integration according to task-relevance regardless of conscious awareness. They also suggest that task-congruent information between prime and target may facilitate response priming even when temporal attention is not selectively oriented to the prime onset time.

  10. What's behind the mask? A look at blood flow changes with prolonged facial pressure and expression using laser Doppler imaging.

    PubMed

    Van-Buendia, Lan B; Allely, Rebekah R; Lassiter, Ronald; Weinand, Christian; Jordan, Marion H; Jeng, James C

    2010-01-01

    Clinically, the initial blanching in burn scar seen on transparent plastic face mask application seems to diminish with time and movement requiring mask alteration. To date, studies quantifying perfusion with prolonged mask use do not exist. This study used laser Doppler imaging (LDI) to assess perfusion through the transparent face mask and movement in subjects with and without burn over time. Five subjects fitted with transparent face masks were scanned with the LDI on four occasions. The four subjects without burn were scanned in the following manner: 1) no mask, 2) mask on while at rest, 3) mask on with alternating intervals of sustained facial expression and rest, and 4) after mask removal. Images were acquired every 3 minutes throughout the 85-minute study period. The subject with burn underwent a shortened scanning protocol to increase comfort. Each face was divided into five regions of interest for analysis. Compared with baseline, mask application decreased perfusion significantly in all subjects (P < .0001). Perfusion did not change during the rest period. There were no significant differences with changing facial expression in any of the regions of interest. On mask removal, all regions of the face demonstrated a hyperemic effect with the chin (P = .05) and each cheek (P < .0001) reaching statistical significance. Perfusion levels did not return to baseline in the chin and cheeks after 30 minutes of mask removal. Perfusions remain constantly low while wearing the face mask, despite changing facial expressions. Changing facial expressions with the mask on did not alter perfusion. Hyperemic response occurs on removal of the mask. This study exposed methodology and statistical issues worth considering when conducting future research with the face, pressure therapy, and with LDI technology.

  11. High-emulation mask recognition with high-resolution hyperspectral video capture system

    NASA Astrophysics Data System (ADS)

    Feng, Jiao; Fang, Xiaojing; Li, Shoufeng; Wang, Yongjin

    2014-11-01

    We present a method for distinguishing human face from high-emulation mask, which is increasingly used by criminals for activities such as stealing card numbers and passwords on ATM. Traditional facial recognition technique is difficult to detect such camouflaged criminals. In this paper, we use the high-resolution hyperspectral video capture system to detect high-emulation mask. A RGB camera is used for traditional facial recognition. A prism and a gray scale camera are used to capture spectral information of the observed face. Experiments show that mask made of silica gel has different spectral reflectance compared with the human skin. As multispectral image offers additional spectral information about physical characteristics, high-emulation mask can be easily recognized.

  12. Face liveness detection for face recognition based on cardiac features of skin color image

    NASA Astrophysics Data System (ADS)

    Suh, Kun Ha; Lee, Eui Chul

    2016-07-01

    With the growth of biometric technology, spoofing attacks have been emerged a threat to the security of the system. Main spoofing scenarios in the face recognition system include the printing attack, replay attack, and 3D mask attack. To prevent such attacks, techniques that evaluating liveness of the biometric data can be considered as a solution. In this paper, a novel face liveness detection method based on cardiac signal extracted from face is presented. The key point of proposed method is that the cardiac characteristic is detected in live faces but not detected in non-live faces. Experimental results showed that the proposed method can be effective way for determining printing attack or 3D mask attack.

  13. [Face protective patches do not reduce facial pressure ulcers in a simulated model of non-invasive ventilation].

    PubMed

    Riquelme M, Hugo; Wood V, David; Martínez F, Santiago; Carmona M, Fernando; Peña V, Axel; Wegner A, Adriana

    2017-06-01

    Noninvasive ventilation (NIV) frequently involves the development of facial pressure ulcers (FPU). Its prevention considers the empirical use of protective patches between skin and mask, in order to reduce the pressure exerted by it. To evaluate the effect of protective patches on the pressure exerted by the facial mask, and its impact on the programmed ventilatory parameters. Bilevel NIV simulated model using full face mask in phantom with a physiological airway (ALS PRO +) in supine position. Forehead, chin and cheekbones pressure were measured using 3 types of standard protective patches versus a control group using pressure sensors (Interlinks Electronics®). The values obtained with the protective patches-mask model were evaluated in the programmed variables maximum inspiratory flow (MIF)), expired tidal volume (Vte) and positive inspiratory pressure (IPAP), with Trilogy 100 ventilator, Respironics®. The programming and recording of the variables was carried out in 8 opportunities in each group by independent operators. There was no decrease in facial pressure with any of the protective patches compared to the control group. Moltopren increased facial pressure at all support points (p < 0.001), increased leakage, it decreased MIF, Vte and IPAP (p < 0.001). Hydrocolloid patches increased facial pressure only in the left cheekbone, increased leakage and decreased MIF. Polyurethane patches did not produce changes in facial pressure or ventilatory variables. The use of protective patches of moltopren, hydrocolloid and polyurethane transparent did not contribute to the decrease of the facial pressure. A deleterious effect of the moltopren and hydrocolloid patches was observed on the administration of ventilatory variables, concluding that the non-use of the protective patches allowed a better administration of the programmed parameters.

  14. Advantages, Disadvantages, Indications, Contraindications and Surgical Technique of Laryngeal Airway Mask

    PubMed Central

    Shekar, Ashim; Balakrishna, Ramdas; Sudarshan, H.; Veena, G. C.; Bhuvaneshwari, S.

    2017-01-01

    The beauty of the laryngeal mask is that it forms an air tight seal enclosing the larynx rather than plugging the pharynx, and avoid airway obstruction in the oropharynx. The goal of its development was to create an intermediate form of airway management face mask and endotracheal tube. Indication for its use includes any procedure that would normally involve the use of a face mask. The laryngeal mask airway was designed as a new concept in airway management and has been gaining a firm position in anesthetic practice. Despite wide spread use the definitive role of the laryngeal mask airway is yet to be established. In some situations, such as after failed tracheal intubation or in oral surgery its use is controversial. There are several unresolved issues, for example the effect of the laryngeal mask on regurgitation and whether or not cricoids pressure prevents placement of mask. We review the techniques of insertion, details of misplacement, and complications associated with use of the laryngeal mask. We then attempt to clarify the role of laryngeal mask in air way management during anesthesia, discussing the advantages and disadvantages as well as indications and contraindications of its use in oral and maxillofacial surgery. PMID:29349045

  15. Advantages, Disadvantages, Indications, Contraindications and Surgical Technique of Laryngeal Airway Mask.

    PubMed

    Jannu, Anubhav; Shekar, Ashim; Balakrishna, Ramdas; Sudarshan, H; Veena, G C; Bhuvaneshwari, S

    2017-12-01

    The beauty of the laryngeal mask is that it forms an air tight seal enclosing the larynx rather than plugging the pharynx, and avoid airway obstruction in the oropharynx. The goal of its development was to create an intermediate form of airway management face mask and endotracheal tube. Indication for its use includes any procedure that would normally involve the use of a face mask. The laryngeal mask airway was designed as a new concept in airway management and has been gaining a firm position in anesthetic practice. Despite wide spread use the definitive role of the laryngeal mask airway is yet to be established. In some situations, such as after failed tracheal intubation or in oral surgery its use is controversial. There are several unresolved issues, for example the effect of the laryngeal mask on regurgitation and whether or not cricoids pressure prevents placement of mask. We review the techniques of insertion, details of misplacement, and complications associated with use of the laryngeal mask. We then attempt to clarify the role of laryngeal mask in air way management during anesthesia, discussing the advantages and disadvantages as well as indications and contraindications of its use in oral and maxillofacial surgery.

  16. Relation of pulmonary responses induced by 6.6-h exposures to 0.08 ppm ozone and 2-h exposures to 0.30 ppm ozone via chamber and face-mask inhalation.

    PubMed

    Adams, William C

    2003-07-01

    While direct comparison of pulmonary responses to 6.6-h exposures to 0.08 to 0.12 ppm ozone O3 have demonstrated that chamber and face-mask inhalation methods yield closely similar results, no comparative study of responses to 2-h intermittent exercise (IE) exposures to higher O3 concentrations have been reported. The present study was designed to achieve three primary objectives: (1) to compare pulmonary function and symptoms effects of a 2-h IE exposure to 0.30 ppm O3 via chamber and via face mask; (2) to compare the pulmonary effects of 6.6-h chamber exposure to 0.08 ppm O3 to those observed in 2-h IE 0.30 ppm O3 exposures via chamber and via face mask; and (3) to examine filtered air (FA) recovery pulmonary and symptoms responses following chamber exposures of 6.6 h to 0.08 ppm O3 and 2 h to 0.30 ppm O3. A simple regression of postexposure percent change in FEV(1.0) for the 2-h IE, 0.30-ppm O3 chamber exposure as a function of postexposure percent change in FEV(1.0) for the 2-h IE, 0.30-ppm O3 exposure with face mask yielded an R(2) of 0.83. Further, a regression of the postexposure FEV(1.0) response to the chamber 6.6-h, 0.08-ppm O3 exposure as a function of postexposure FEV(1.0) response to the face mask 2-h IE, 0.30-ppm O3 exposure (R(2) of 0.34) was similar to the 0.40 value obtained for the two chamber exposures FEV(1.0) response comparison. Results of the 1.4-h FA recovery following the two chamber O3 exposures showed different rates of FEV(1.0) and symptoms rectification that appeared related to the total O3 dose (product of O3 concentration, ventilation rate, and duration). More data are needed to clarify short-term recovery of O3-induced pulmonary effects and how they may be related to the more abundant data available on the delayed recovery of pulmonary function seen over longer time periods, such as 24 h.

  17. More Realistic Face Model Surface Improves Relevance of Pediatric In-Vitro Aerosol Studies

    PubMed Central

    Amirav, Israel; Halamish, Asaf; Gorenberg, Miguel; Omar, Hamza; Newhouse, Michael T.

    2015-01-01

    Background Various hard face models are commonly used to evaluate the efficiency of aerosol face masks. Softer more realistic “face” surface materials, like skin, deform upon mask application and should provide more relevant in-vitro tests. Studies that simultaneously take into consideration many of the factors characteristic of the in vivo face are lacking. These include airways, various application forces, comparison of various devices, comparison with a hard-surface model and use of a more representative model face based on large numbers of actual faces. Aim To compare mask to “face” seal and aerosol delivery of two pediatric masks using a soft vs. a hard, appropriately representative, pediatric face model under various applied forces. Methods Two identical face models and upper airways replicas were constructed, the only difference being the suppleness and compressibility of the surface layer of the “face.” Integrity of the seal and aerosol delivery of two different masks [AeroChamber (AC) and SootherMask (SM)] were compared using a breath simulator, filter collection and realistic applied forces. Results The soft “face” significantly increased the delivery efficiency and the sealing characteristics of both masks. Aerosol delivery with the soft “face” was significantly greater for the SM compared to the AC (p< 0.01). No statistically significant difference between the two masks was observed with the hard “face.” Conclusions The material and pliability of the model “face” surface has a significant influence on both the seal and delivery efficiency of face masks. This finding should be taken into account during in-vitro aerosol studies. PMID:26090661

  18. Comparison of the effectiveness of high flow nasal oxygen cannula vs. standard non-rebreather oxygen face mask in post-extubation intensive care unit patients.

    PubMed

    Brotfain, Evgeni; Zlotnik, Alexander; Schwartz, Andrei; Frenkel, Amit; Koyfman, Leonid; Gruenbaum, Shaun E; Klein, Moti

    2014-11-01

    Optimal oxygen supply is the cornerstone of the management of critically ill patients after extubation, especially in patients at high risk for extubation failure. In recent years, high flow oxygen system devices have offered an appropriate alternative to standard oxygen therapy devices such as conventional face masks and nasal prongs. To assess the clinical effects of high flow nasal cannula (HFNC) compared with standard oxygen face masks in Intensive Care Unit (ICU) patients after extubation. We retrospectively analyzed 67 consecutive ventilated critical care patients in the ICU over a period of 1 year. The patients were allocated to two treatment groups: HFNC (34 patients, group 1) and non-rebreathing oxygen face mask (NRB) (33 patients, group 2). Vital respiratory and hemodynamic parameters were assessed prior to extubation and 6 hours after extubation. The primary clinical outcomes measured were improvement in oxygenation, ventilation-free days, re-intubation, ICU length of stay, and mortality. The two groups demonstrated similar hemodynamic patterns before and after extubation. The respiratory rate was slightly elevated in both groups after extubation with no differences observed between groups. There were no statistically significant clinical differences in PaCO2. However, the use of HFNC resulted in improved PaO2/FiO2 post-extubation (P < 0.05). There were more ventilator-free days in the HFNC group (P< 0.05) and fewer patients required reintubation (1 vs. 6). There were no differences in ICU length of stay or mortality. This study demonstrated better oxygenation for patients treated with HFNC compared with NRB after extubation. HFNC may be more effective than standard oxygen supply devices for oxygenation in the post-extubation period.

  19. Atypical parietal lobe activity to subliminal faces in youth with a family history of alcoholism

    PubMed Central

    Peraza, Jennifer; Cservenka, Anita; Herting, Megan M.; Nagel, Bonnie J.

    2015-01-01

    Background Adults with alcohol use disorders (AUDs) show different behavioral and neurological functioning during emotional processing tasks from healthy controls. Adults with a family history (FHP) of AUD also show different activation in limbic brain areas, such as the amygdala. However, it is unclear if this pattern exists during adolescence before any episodes of heavy alcohol use. Objectives We hypothesized that the amygdalar response to subliminally-presented fearful faces would be reduced in FHP adolescents compared to peers who were family history negative (FHN) for AUD. Method An adapted Masked Faces paradigm was used to examine blood oxygen level-dependent response to subliminal fearful vs. neutral faces in 14 FHP (6 females, 8 males) and 15 FHN (6 females, 9 males) youth, ages 11–15 years. Both FHP and FHN youth had no history of heavy alcohol consumption. Results A significant difference was seen between groups in the left superior parietal lobule FHN youth showed deactivation to fearful and neutral masked faces compared to baseline, whereas FHP youth showed deactivation only to fearful masked faces. No significant differences in amygdalar activation were seen between groups. Conclusion The left superior parietal lobule is part of the fronto-parietal network, which has been implicated in attentional control. Lack of reduced neural activity to neutral faces among FHP youth may represent differences in suppressing attention networks to less salient emotional stimuli, or perhaps, a higher threshold of saliency for emotional stimuli among at-risk youth. PMID:25268683

  20. Atypical parietal lobe activity to subliminal faces in youth with a family history of alcoholism.

    PubMed

    Peraza, Jennifer; Cservenka, Anita; Herting, Megan M; Nagel, Bonnie J

    2015-03-01

    Adults with alcohol use disorders (AUDs) show different behavioral and neurological functioning during emotional processing tasks from healthy controls. Adults with a family history (FHP) of AUD also show different activation in limbic brain areas, such as the amygdala. However, it is unclear if this pattern exists during adolescence before any episodes of heavy alcohol use. We hypothesized that the amygdalar response to subliminally-presented fearful faces would be reduced in FHP adolescents compared to peers who were family history negative (FHN) for AUD. An adapted Masked Faces paradigm was used to examine blood oxygen level-dependent response to subliminal fearful vs. neutral faces in 14 FHP (6 females, 8 males) and 15 FHN (6 females, 9 males) youth, ages 11-15 years. Both FHP and FHN youth had no history of heavy alcohol consumption. A significant difference was seen between groups in the left superior parietal lobule FHN youth showed deactivation to fearful and neutral masked faces compared to baseline, whereas FHP youth showed deactivation only to fearful masked faces. No significant differences in amygdalar activation were seen between groups. The left superior parietal lobule is part of the fronto-parietal network, which has been implicated in attentional control. Lack of reduced neural activity to neutral faces among FHP youth may represent differences in suppressing attention networks to less salient emotional stimuli, or perhaps, a higher threshold of saliency for emotional stimuli among at-risk youth.

  1. Mask versus Nasal Tube for Stabilization of Preterm Infants at Birth: Respiratory Function Measurements.

    PubMed

    van Vonderen, Jeroen J; Kamlin, C Omar; Dawson, Jennifer A; Walther, Frans J; Davis, Peter G; te Pas, Arjan B

    2015-07-01

    To compare the nasal tube with face mask as interfaces for stabilization of very preterm infants at birth by using physiological measurements of leak, obstruction, and expired tidal volumes during positive pressure ventilation (PPV). In the delivery room, 43 infants <30 weeks gestation were allocated to receive respiratory support by nasal tube or face mask. Respiratory function, heart rate, and oxygen saturation were measured. Occurrence of obstruction, amount of leak, and tidal volumes were compared using a Mann-Whitney U test or a Fisher exact test. The first 5 minutes after initiation of PPV were analyzed (1566 inflations in the nasal tube group and 1896 inflations in the face mask group). Spontaneous breathing coincided with PPV in 32% of nasal tube and 34% of face mask inflations. During inflations, higher leak was observed using nasal tube compared with face mask (98% [33%-100%] vs 14 [0%-39%]; P < .0001). Obstruction occurred more often (8.2% vs 1.1%; P < .0001). Expired tidal volumes were significantly lower during inflations when using nasal tube compared with face mask (0.0 [0.0-3.1] vs 9.9 [5.5-12.8] mL/kg; P < .0001) and when spontaneous breathing coincided with PPV (4.4 [2.1-8.4] vs 9.6 [5.4-15.2] mL/kg; P < .0001) but were similar during breathing on continuous positive airway pressure (4.7 [2.8-6.9] vs 4.8 [2.7-7.9] mL/kg; P > 0.05). Heart rate was not significantly different between groups, but oxygen saturation was significantly lower in the nasal tube group the first 2 minutes after start of respiratory support. The use of a nasal tube led to large leak, more obstruction, and inadequate tidal volumes compared with face mask. Trial registration Registered with the Dutch Trial Registry (NTR 2061) and the Australia and New Zealand Clinical Trials Register (ACTRN 12610000230055). Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Feature saliency in judging the sex and familiarity of faces.

    PubMed

    Roberts, T; Bruce, V

    1988-01-01

    Two experiments are reported on the effect of feature masking on judgements of the sex and familiarity of faces. In experiment 1 the effect of masking the eyes, nose, or mouth of famous and nonfamous, male and female faces on response times in two tasks was investigated. In the first, recognition, task only masking of the eyes had a significant effect on response times. In the second, sex-judgement, task masking of the nose gave rise to a significant and large increase in response times. In experiment 2 it was found that when facial features were presented in isolation in a sex-judgement task, responses to noses were at chance level, unlike those for eyes or mouths. It appears that visual information available from the nose in isolation from the rest of the face is not sufficient for sex judgement, yet masking of the nose may disrupt the extraction of information about the overall topography of the face, information that may be more useful for sex judgement than for identification of a face.

  3. Easy facial analysis using the facial golden mask.

    PubMed

    Kim, Yong-Ha

    2007-05-01

    For over 2000 years, many artists and scientists have tried to understand or quantify the form of the perfect, ideal, or most beautiful face both in art and in vivo (life). A mathematical relationship has been consistently and repeatedly reported to be present in beautiful things. This particular relationship is the golden ratio. It is a mathematical ratio of 1.618:1 that seems to appear recurrently in beautiful things in nature as well as in other things that are seen as beautiful. Dr. Marquardt made the facial golden mask that contains and includes all of the one-dimensional and two-dimensional geometric golden elements formed from the golden ratio. The purpose of this study is to evaluate the usefulness of the golden facial mask. In 40 cases, the authors applied the facial golden mask to preoperative and postoperative photographs and scored each photograph on a 1 to 5 scale from the perspective of their personal aesthetic views. The score was lower when the facial deformity was severe, whereas it was higher when the face was attractive. Compared with the average scores of facial mask applied photographs and nonapplied photographs using a nonparametric test, statistical significance was not reached (P > 0.05). This implies that the facial golden mask may be used as an analytical tool. The facial golden mask is easy to apply, inexpensive, and relatively objective. Therefore, the authors introduce it as a useful facial analysis.

  4. Dissociations of subliminal and supraliminal self-face from other-face processing: behavioral and ERP evidence.

    PubMed

    Geng, Haiyan; Zhang, Shen; Li, Qi; Tao, Ran; Xu, Shan

    2012-10-01

    Self-related information has been found to be processed more quickly and accurately in studies with supraliminal self-stimuli and traditional paradigms such as masked priming. We conducted two experiments to investigate whether subliminal self-face processing enjoys this advantage and the neural correlates of processing self-faces at both subliminal and supraliminal levels. We found that self-faces were quicker than famous-other faces to gain dominance against dynamic noise patterns during prolonged interocular suppression to enter awareness (Experiment 1). Meanwhile, subliminal contrast of self- and famous-other face processing was reflected in a reduced early vertex positive potential (VPP) component, whereas supraliminal self-other face differentiation was reflected in an enhanced N170, as well as a more positive late component (300-580ms, Experiment 2) to the self-face. The clear dissociations of self- and other-face processing found across our two experiments validate the self advantage. Our findings also contribute to understandings of the mechanisms underlying self-face processing at different levels of awareness. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. The effectiveness of nasal mask vs face mask ventilation in anesthetized, apneic pediatric subjects over 2 years of age: a randomized controlled trial.

    PubMed

    Itagaki, Taiga; Gubin, Tatyana A; Sayal, Puneet; Jiang, Yandong; Kacmarek, Robert M; Anderson, Thomas Anthony

    2016-02-01

    We hypothesized that anesthetized, apneic children could be ventilated equivalently or more efficiently by nasal mask ventilation (NMV) than face mask ventilation (FMV). The aim of this randomized controlled study was to test this hypothesis by comparing the expiratory tidal volume (Vte) between NMV and FMV. After the induction of anesthesia, 41 subjects, 3-17 years of age without anticipated difficult mask ventilation, were randomly assigned to receive either NMV or FMV with neck extension. Both groups were ventilated with pressure control ventilation (PCV) at 20 cmH2 O of peak inspiratory pressure (PIP) with positive end-expiratory pressure (PEEP) levels of 0, 5, and 10 cmH2 O. An additional mouth closing maneuver (MCM) was applied for the NMV group. The Vte was higher in the FMV group compared with the NMV group (median difference [95% CI]: 8.4 [5.5-11.6] ml·kg(-1) ; P < 0.001) when MCM was not applied. NMV achieved less PEEP than FMV (median difference [95% CI]: 5.0 [4.3-5.3] cmH2 O at 10 cmH2 O; P < 0.001) though both groups achieved the set PIP level. In the NMV group, MCM markedly increased Vte (median increase [95% CI]: 5.9 [2.5-9.0] ml·kg(-1) ; P < 0.005) and PEEP (median increase [95% CI]: 5.0 [0.6-8.6] cmH2 O at 10 cmH2 O; P < 0.005); however, PEEP was highly variable and lower than that of FMV (median difference [95% CI]: 2.5 [0.8-8.5] cmH2 O at 10 cmH2 O; P < 0.05). In anesthetized, apneic children greater than 2 years of age ventilated with an anesthesia ventilator and neck extension, FMV established a greater Vte than NMV regardless of mouth status. NMV could not maintain the set PEEP level due to an air leak from the mouth. The MCM increased the Vte and PEEP. © 2016 John Wiley & Sons Ltd.

  6. Respiratory source control using a surgical mask: An in vitro study.

    PubMed

    Patel, Rajeev B; Skaria, Shaji D; Mansour, Mohamed M; Smaldone, Gerald C

    2016-07-01

    Cough etiquette and respiratory hygiene are forms of source control encouraged to prevent the spread of respiratory infection. The use of surgical masks as a means of source control has not been quantified in terms of reducing exposure to others. We designed an in vitro model using various facepieces to assess their contribution to exposure reduction when worn at the infectious source (Source) relative to facepieces worn for primary (Receiver) protection, and the factors that contribute to each. In a chamber with various airflows, radiolabeled aerosols were exhaled via a ventilated soft-face manikin head using tidal breathing and cough (Source). Another manikin, containing a filter, quantified recipient exposure (Receiver). The natural fit surgical mask, fitted (SecureFit) surgical mask and an N95-class filtering facepiece respirator (commonly known as an "N95 respirator") with and without a Vaseline-seal were tested. With cough, source control (mask or respirator on Source) was statistically superior to mask or unsealed respirator protection on the Receiver (Receiver protection) in all environments. To equal source control during coughing, the N95 respirator must be Vaseline-sealed. During tidal breathing, source control was comparable or superior to mask or respirator protection on the Receiver. Source control via surgical masks may be an important adjunct defense against the spread of respiratory infections. The fit of the mask or respirator, in combination with the airflow patterns in a given setting, are significant contributors to source control efficacy. Future clinical trials should include a surgical mask source control arm to assess the contribution of source control in overall protection against airborne infection.

  7. Respiratory source control using a surgical mask: An in vitro study

    PubMed Central

    Patel, Rajeev B.; Skaria, Shaji D.; Mansour, Mohamed M.; Smaldone, Gerald C.

    2016-01-01

    ABSTRACT Cough etiquette and respiratory hygiene are forms of source control encouraged to prevent the spread of respiratory infection. The use of surgical masks as a means of source control has not been quantified in terms of reducing exposure to others. We designed an in vitro model using various facepieces to assess their contribution to exposure reduction when worn at the infectious source (Source) relative to facepieces worn for primary (Receiver) protection, and the factors that contribute to each. In a chamber with various airflows, radiolabeled aerosols were exhaled via a ventilated soft-face manikin head using tidal breathing and cough (Source). Another manikin, containing a filter, quantified recipient exposure (Receiver). The natural fit surgical mask, fitted (SecureFit) surgical mask and an N95-class filtering facepiece respirator (commonly known as an “N95 respirator”) with and without a Vaseline-seal were tested. With cough, source control (mask or respirator on Source) was statistically superior to mask or unsealed respirator protection on the Receiver (Receiver protection) in all environments. To equal source control during coughing, the N95 respirator must be Vaseline-sealed. During tidal breathing, source control was comparable or superior to mask or respirator protection on the Receiver. Source control via surgical masks may be an important adjunct defense against the spread of respiratory infections. The fit of the mask or respirator, in combination with the airflow patterns in a given setting, are significant contributors to source control efficacy. Future clinical trials should include a surgical mask source control arm to assess the contribution of source control in overall protection against airborne infection. PMID:26225807

  8. Reducing personal exposure to particulate air pollution improves cardiovascular health in patients with coronary heart disease.

    PubMed

    Langrish, Jeremy P; Li, Xi; Wang, Shengfeng; Lee, Matthew M Y; Barnes, Gareth D; Miller, Mark R; Cassee, Flemming R; Boon, Nicholas A; Donaldson, Ken; Li, Jing; Li, Liming; Mills, Nicholas L; Newby, David E; Jiang, Lixin

    2012-03-01

    Air pollution exposure increases cardiovascular morbidity and mortality and is a major global public health concern. We investigated the benefits of reducing personal exposure to urban air pollution in patients with coronary heart disease. In an open randomized crossover trial, 98 patients with coronary heart disease walked on a predefined route in central Beijing, China, under different conditions: once while using a highly efficient face mask, and once while not using the mask. Symptoms, exercise, personal air pollution exposure, blood pressure, heart rate, and 12-lead electrocardiography were monitored throughout the 24-hr study period. Ambient air pollutants were dominated by fine and ultrafine particulate matter (PM) that was present at high levels [74 μg/m³ for PM(2.5) (PM with aerodynamic diamater <2.5 µm)]. Consistent with traffic-derived sources, this PM contained organic carbon and polycyclic aromatic hydrocarbons and was highly oxidizing, generating large amounts of free radicals. The face mask was well tolerated, and its use was associated with decreased self-reported symptoms and reduced maximal ST segment depression (-142 vs. -156 μV, p = 0.046) over the 24-hr period. When the face mask was used during the prescribed walk, mean arterial pressure was lower (93 ± 10 vs. 96 ± 10 mmHg, p = 0.025) and heart rate variability increased (high-frequency power: 54 vs. 40 msec², p = 0.005; high-frequency normalized power: 23.5 vs. 20.5 msec, p = 0.001; root mean square successive differences: 16.7 vs. 14.8 msec, p = 0.007). However, mask use did not appear to influence heart rate or energy expenditure. Reducing personal exposure to air pollution using a highly efficient face mask appeared to reduce symptoms and improve a range of cardiovascular health measures in patients with coronary heart disease. Such interventions to reduce personal exposure to PM air pollution have the potential to reduce the incidence of cardiovascular events in this highly

  9. Anticipating and controlling mask costs within EDA physical design

    NASA Astrophysics Data System (ADS)

    Rieger, Michael L.; Mayhew, Jeffrey P.; Melvin, Lawrence S.; Lugg, Robert M.; Beale, Daniel F.

    2003-08-01

    For low k1 lithography, more aggressive OPC is being applied to critical layers, and the number of mask layers with OPC treatments is growing rapidly. The 130 nm, process node required, on average, 8 layers containing rules- or model-based OPC. The 90 nm node will have 16 OPC layers, of which 14 layers contain aggressive model-based OPC. This escalation of mask pattern complexity, coupled with the predominant use of vector-scan e-beam (VSB) mask writers contributes to the rising costs of advanced mask sets. Writing times for OPC layouts are several times longer than for traditional layouts, making mask exposure the single largest cost component for OPC masks. Lower mask yields, another key factor in higher mask costs, is also aggravated by OPC. Historical mask set costs are plotted below. The initial cost of a 90 nm-node mask set will exceed one million dollars. The relative impact of mask cost on chip depends on how many total wafers are printed with each mask set. For many foundry chips, where unit production is often well below 1000 wafers, mask costs are larger than wafer processing costs. Further increases in NRE may begin to discourage these suppliers' adoption to 90 nm and smaller nodes. In this paper we will outline several alternatives for reducing mask costs by strategically leveraging dimensional margins. Dimensional specifications for a particular masking layer usually are applied uniformly to all features on that layer. As a practical matter, accuracy requirements on different features in the design may vary widely. Take a polysilicon layer, for example: global tolerance specifications for that layer are driven by the transistor-gate requirements; but these parameters over-specify interconnect feature requirements. By identifying features where dimensional accuracy requirements can be reduced, additional margin can be leveraged to reduce OPC complexity. Mask writing time on VSB tools will drop in nearly direct proportion to reduce shot count. By

  10. Shadows alter facial expressions of Noh masks.

    PubMed

    Kawai, Nobuyuki; Miyata, Hiromitsu; Nishimura, Ritsuko; Okanoya, Kazuo

    2013-01-01

    A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding how attached shadows of the Noh masks influence the observers' recognition of the emotional expressions. In Experiment 1, neutral-faced Noh masks having the attached shadows of the happy/sad masks were recognized as bearing happy/sad expressions, respectively. This was true for all four types of masks each of which represented a character differing in sex and age, even though the original characteristics of the masks also greatly influenced the evaluation of emotions. Experiment 2 further revealed that frontal Noh mask images having shadows of upward/downward tilted masks were evaluated as sad/happy, respectively. This was consistent with outcomes from preceding studies using actually tilted Noh mask images. Results from the two experiments concur that purely manipulating attached shadows of the different types of Noh masks significantly alters the emotion recognition. These findings go in line with the mysterious facial expressions observed in Western paintings, such as the elusive qualities of Mona Lisa's smile. They also agree with the aesthetic principle of Japanese traditional art "yugen (profound grace and subtlety)", which highly appreciates subtle emotional expressions in the darkness.

  11. The difficult business model for mask equipment makers and mask infrastructure development support from consortia and governments

    NASA Astrophysics Data System (ADS)

    Hector, Scott

    2005-11-01

    The extension of optical projection lithography through immersion to patterning features with half pitch <=65 nm is placing greater demands on the mask. Strong resolution enhancement techniques (RETs), such as embedded and alternating phase shift masks and complex model-based optical proximity correction, are required to compensate for diffraction and limited depth of focus (DOF). To fabricate these masks, many new or upgraded tools are required to write patterns, measure feature sizes and placement, inspect for defects, review defect printability and repair defects on these masks. Beyond the significant technical challenges, suppliers of mask fabrication equipment face the challenge of being profitable in the small market for mask equipment while encountering significant R&D expenses to bring new generations of mask fabrication equipment to market. The total available market for patterned masks is estimated to be $2.5B to $2.9B per year. The patterned mask market is about 20% of the market size for lithography equipment and materials. The total available market for mask-making equipment is estimated to be about $800M per year. The largest R&D affordability issue arises for the makers of equipment for fabricating masks where total available sales are typically less than ten units per year. SEMATECH has used discounted cash flow models to predict the affordable R&D while maintaining industry accepted internal rates of return. The results have been compared to estimates of the total R&D cost to bring a new generation of mask equipment to market for various types of tools. The analysis revealed that affordability of the required R&D is a significant problem for many suppliers of mask-making equipment. Consortia such as SEMATECH and Selete have played an important role in cost sharing selected mask equipment and material development projects. Governments in the United States, in Europe and in Japan have also helped equipment suppliers with support for R&D. This paper

  12. Work of breathing using different interfaces in spontaneous positive pressure ventilation: helmet, face-mask, and endotracheal tube.

    PubMed

    Oda, Shinya; Otaki, Kei; Yashima, Nozomi; Kurota, Misato; Matsushita, Sachiko; Kumasaka, Airi; Kurihara, Hutaba; Kawamae, Kaneyuki

    2016-08-01

    Noninvasive positive pressure ventilation (NPPV) using a helmet is expected to cause inspiratory trigger delay due to the large collapsible and compliant chamber. We compared the work of breathing (WOB) of NPPV using a helmet or a full face-mask with that of invasive ventilation by tracheal intubation. We used a lung model capable of simulating spontaneous breathing (LUNGOO; Air Water Inc., Japan). LUNGOO was set at compliance (C) = 50 mL/cmH2O and resistance (R) = 5 cmH2O/L/s for normal lung simulation, C = 20 mL/cmH2O and R = 5 cmH2O/L/s for restrictive lung, and C = 50 mL/cmH2O and R = 20 cmH2O/L/s for obstructive lung. Muscle pressure was fixed at 25 cmH2O and respiratory rate at 20 bpm. Pressure support ventilation and continuous positive airway pressure were performed with each interface placed on a dummy head made of reinforced plastic that was connected to LUNGOO. We tested the inspiratory WOB difference between the interfaces with various combinations of ventilator settings (positive end-expiratory pressure 5 cmH2O; pressure support 0, 5, and 10 cmH2O). In the normal lung and restrictive lung models, WOB decreased more with the face-mask than the helmet, especially when accompanied by the level of pressure support. In the obstructive lung model, WOB with the helmet decreased compared with the other two interfaces. In the mixed lung model, there were no significant differences in WOB between the three interfaces. NPPV using a helmet is more effective than the other interfaces for WOB in obstructive lung disease.

  13. Gestalt grouping and common onset masking.

    PubMed

    Kahan, Todd A; Mathis, Katherine M

    2002-11-01

    A four-dot mask that surrounds and is presented simultaneously with a briefly presented target will reduce a person's ability to identity that target if the mask persists beyond target offset and attention is divided (Enns & Di Lollo, 1997, 2000). This masking effect, referred to as common onset masking, reflects reentrant processing in the visual system and can best be explained with a theory of object substitution (Di Lollo, Enns, & Rensink, 2000). In the present experiments, we investigated whether Gestalt grouping variables would influence the strength of common onset masking. The results indicated that (1) masking was impervious to grouping by form, similarity of color, position, luminance polarity, and common region and (2) masking increased with the number of elements in the masking display.

  14. Shadows Alter Facial Expressions of Noh Masks

    PubMed Central

    Kawai, Nobuyuki; Miyata, Hiromitsu; Nishimura, Ritsuko; Okanoya, Kazuo

    2013-01-01

    Background A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding how attached shadows of the Noh masks influence the observers’ recognition of the emotional expressions. Methodology/Principal Findings In Experiment 1, neutral-faced Noh masks having the attached shadows of the happy/sad masks were recognized as bearing happy/sad expressions, respectively. This was true for all four types of masks each of which represented a character differing in sex and age, even though the original characteristics of the masks also greatly influenced the evaluation of emotions. Experiment 2 further revealed that frontal Noh mask images having shadows of upward/downward tilted masks were evaluated as sad/happy, respectively. This was consistent with outcomes from preceding studies using actually tilted Noh mask images. Conclusions/Significance Results from the two experiments concur that purely manipulating attached shadows of the different types of Noh masks significantly alters the emotion recognition. These findings go in line with the mysterious facial expressions observed in Western paintings, such as the elusive qualities of Mona Lisa’s smile. They also agree with the aesthetic principle of Japanese traditional art “yugen (profound grace and subtlety)”, which highly appreciates subtle emotional expressions in the darkness. PMID:23940748

  15. Alternating phase-shift mask and binary mask for 45-nm node and beyond: the impact on the mask error control

    NASA Astrophysics Data System (ADS)

    Kojima, Yosuke; Shirasaki, Masanori; Chiba, Kazuaki; Tanaka, Tsuyoshi; Inazuki, Yukio; Yoshikawa, Hiroki; Okazaki, Satoshi; Iwase, Kazuya; Ishikawa, Kiichi; Ozawa, Ken

    2007-05-01

    For 45 nm node and beyond, the alternating phase-shift mask (alt. PSM), one of the most expected resolution enhancement technologies (RET) because of its high image contrast and small mask error enhancement factor (MEEF), and the binary mask (BIM) attract attention. Reducing CD and registration errors and defect are their critical issues. As the solution, the new blank for alt. PSM and BIM is developed. The top film of new blank is thin Cr, and the antireflection film and shielding film composed of MoSi are deposited under the Cr film. The mask CD performance is evaluated for through pitch, CD linearity, CD uniformity, global loading, resolution and pattern fidelity, and the blank performance is evaluated for optical density, reflectivity, sheet resistance, flatness and defect level. It is found that the performance of new blank is equal to or better than that of conventional blank in all items. The mask CD performance shows significant improvement. The lithography performance of new blank is confirmed by wafer printing and AIMS measurement. The full dry type alt. PSM has been used as test plate, and the test results show that new blank can almost meet the specifications of pi-0 CD difference, CD uniformity and process margin for 45 nm node. Additionally, the new blank shows the better pattern fidelity than that of conventional blank on wafer. AIMS results are almost same as wafer results except for the narrowest pattern. Considering the result above, this new blank can reduce the mask error factors of alt. PSM and BIM for 45 nm node and beyond.

  16. Cumulative childhood interpersonal trauma is associated with reduced cortical differentiation between threat and non-threat faces in posttraumatic stress disorder adults.

    PubMed

    Chu, Denise A; Bryant, Richard A; Gatt, Justine M; Harris, Anthony Wf

    2018-03-01

    Posttraumatic stress disorder and childhood trauma frequently co-occur. Both are associated with abnormal neural responses to salient emotion stimuli. As childhood trauma is a risk factor for posttraumatic stress disorder, differentiating between their neurophysiological effects is necessary to elucidate the neural pathways by which childhood trauma exposure contributes to increased posttraumatic stress disorder risks. Face-specific N170 evoked response potentials for backward-masked (non-conscious) and conscious threat (fear, angry) and non-threat (happy) faces were measured in 77 adults (18-64 years old, 64% women, 78% right-handed) symptomatic for posttraumatic stress disorder. Differences in N170 peak amplitudes for fear-versus-happy and angry-versus-happy faces at bilateral temporo-occipital (T5, T6) sites were computed. The effect of cumulative exposure to childhood interpersonal trauma, other childhood trauma, adult trauma, depression and posttraumatic stress disorder symptom severity on the N170 response was assessed using hierarchical multiple regression analyses. T5 N170 peak amplitudes for non-conscious fear-versus-happy faces were inversely related to cumulative childhood interpersonal trauma after accounting for socio-demographic, clinical symptom and other trauma factors. Posttraumatic stress disorder Avoidance was positively associated with N170 peak amplitudes for non-conscious fear-versus-happy faces, primarily due to reduced N170 responsivity to happy faces. Childhood interpersonal trauma exposure is associated with reduced discrimination between fear and happy faces, while avoidance symptom severity is associated with dampened responsivity to automatically processed happy faces in posttraumatic stress disorder adults. Results are discussed in terms of the likely contributions of impaired threat discrimination and deficient reward processing during neural processing of salient emotion stimuli, to increased risks of posttraumatic stress disorder

  17. Mask Making: The Use of the Expressive Arts in Leadership Development.

    ERIC Educational Resources Information Center

    Jones, Angela Thomas

    1992-01-01

    Outdoor educators in training engaged in a mask-making activity involving partners. One person made the mask and the other provided his or her face as the mold. The anxiety-provoking experience invited an intimate exchange between partners around issues of intimacy, trust, and compassion. (KS)

  18. Summation versus suppression in metacontrast masking: On the potential pitfalls of using metacontrast masking to assess perceptual-motor dissociation.

    PubMed

    Cardoso-Leite, Pedro; Waszak, Florian

    2014-07-01

    A briefly flashed target stimulus can become "invisible" when immediately followed by a mask-a phenomenon known as backward masking, which constitutes a major tool in the cognitive sciences. One form of backward masking is termed metacontrast masking. It is generally assumed that in metacontrast masking, the mask suppresses activity on which the conscious perception of the target relies. This assumption biases conclusions when masking is used as a tool-for example, to study the independence between perceptual detection and motor reaction. This is because other models can account for reduced perceptual performance without requiring suppression mechanisms. In this study, we used signal detection theory to test the suppression model against an alternative view of metacontrast masking, referred to as the summation model. This model claims that target- and mask-related activations fuse and that the difficulty in detecting the target results from the difficulty to discriminate this fused response from the response produced by the mask alone. Our data support this alternative view. This study is not a thorough investigation of metacontrast masking. Instead, we wanted to point out that when a different model is used to account for the reduced perceptual performance in metacontrast masking, there is no need to postulate a dissociation between perceptual and motor responses to account for the data. Metacontrast masking, as implemented in the Fehrer-Raab situation, therefore is not a valid method to assess perceptual-motor dissociations.

  19. The Many Faces of Language.

    ERIC Educational Resources Information Center

    Werdmann, Anne M.

    In a sixth-grade unit, students learned about people's facial expressions through careful observation, recording, reporting, and generalizing. The students studied the faces of people of various ages; explored "masks" that people wear in different situations; learned about the use of ritual masks; made case studies of individuals to show…

  20. Retention of pediatric bag-mask ventilation efficacy skill by inexperienced medical student resuscitators using standard bag-mask ventilation masks, pocket masks, and blob masks.

    PubMed

    Kitagawa, Kory H; Nakamura, Nina M; Yamamoto, Loren

    2006-03-01

    To measure the ventilation efficacy with three single-sized mask types on infant and child manikin models. Medical students were recruited as study subjects inasmuch as they are inexperienced resuscitators. They were taught proper bag-mask ventilation (BMV) according to the American Heart Association guidelines on an infant and a child manikin. Subjects completed a BMV attempt successfully using the adult standard mask (to simulate the uncertainty of mask selection), pocket mask, and blob mask. Each attempt consisted of 5 ventilations assessed by chest rise of the manikin. Study subjects were asked which mask was easiest to use. Four to six weeks later, subjects repeated the procedure with no instructions (to simulate an emergency BMV encounter without immediate pre-encounter teaching). Forty-six volunteer subjects were studied. During the first attempt, subjects preferred the standard and blob masks over the pocket mask. For the second attempt, the blob mask was preferred over the standard mask, and few liked the pocket mask. Using the standard, blob, and pocket masks on the child manikin, 39, 42, and 20 subjects, respectively, were able to achieve adequate ventilation. Using the standard, blob, and pocket masks on the infant manikin, 45, 45, and 11 subjects, respectively, were able to achieve adequate ventilation. Both the standard and blob masks are more effective than the pocket mask at achieving adequate ventilation on infant and child manikins in this group of inexperienced medical student resuscitators, who most often preferred the blob mask.

  1. How color, regularity, and good Gestalt determine backward masking.

    PubMed

    Sayim, Bilge; Manassi, Mauro; Herzog, Michael

    2014-06-18

    The strength of visual backward masking depends on the stimulus onset asynchrony (SOA) between target and mask. Recently, it was shown that the conjoint spatial layout of target and mask is as crucial as SOA. Particularly, masking strength depends on whether target and mask group with each other. The same is true in crowding where the global spatial layout of the flankers and target-flanker grouping determine crowding strength. Here, we presented a vernier target followed by different flanker configurations at varying SOAs. Similar to crowding, masking of a red vernier target was strongly reduced for arrays of 10 green compared with 10 red flanking lines. Unlike crowding, single green lines flanking the red vernier showed strong masking. Irregularly arranged flanking lines yielded stronger masking than did regularly arranged lines, again similar to crowding. While cuboid flankers reduced crowding compared with single lines, this was not the case in masking. We propose that, first, masking is reduced when the flankers are part of a larger spatial structure. Second, spatial factors counteract color differences between the target and the flankers. Third, complex Gestalts, such as cuboids, seem to need longer processing times to show ungrouping effects as observed in crowding. Strong parallels between masking and crowding suggest similar underlying mechanism; however, temporal factors in masking additionally modulate performance, acting as an additional grouping cue. © 2014 ARVO.

  2. Satisfaction with Facial Appearance and Quality of Life after Treatment of Face Scars with a Transparent Facial Pressure Mask.

    PubMed

    Kant, S B; Colla, C; Van den Kerckhove, E; Van der Hulst, R R W J; Piatkowski de Grzymala, A

    2018-06-01

    Treatment of facial hypertrophic scars and deformities has developed from the use of elastic fabric hoods to transparent facemasks. The clinical effects of these masks have been described. However, the psychological impact of wearing such a mask is not well documented. The aim of this study was to assess patients' satisfaction with their current facial appearance, to assess the end result of facemask therapy, and to assess the decision to have undergone facemask therapy by means of four different FACE-Q questionnaires. Out of the eligible 87 patients who completed the facemask therapy between January 2012 and November 2017, 42 filled out the questionnaires. These patients wore a custom-fabricated facemask because of facial hypertrophic scars and severe postsurgical facial irregularities. Patients who wore the mask 12 to 16 hours per day were significantly more satisfied with the end result compared with those who wore it 4 to 8 hours daily. Also, patients who wore the mask 8 to 12 and 12 to 16 hours each day were more satisfied to have undergone therapy compared with those who wore it 4 to 8 hours daily. Furthermore, patients who finished therapy 3 to 4 years and 4 to 5 years ago reported a significant higher satisfaction with facial appearance compared with those who completed therapy in a time period shorter than 1 year ago. Patients who finished therapy 3 to 4 years ago reported higher satisfaction with their facial appearance compared with those who finished therapy 2 to 3 years ago. Additionally, the Patient and Observer Scar Assessments Score (POSAS) showed a significant reduction between start and end of therapy. This study shows facemask therapy to result in long-lasting stable results. It also shows a longer daily wearing of the facemask to result in the highest satisfaction according to patients. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  3. Being forward not backward: lexical limits to masked priming.

    PubMed

    Davis, Chris; Kim, Jeesun; Forster, Kenneth I

    2008-05-01

    This study investigated whether masked priming is mediated by existing memory representations by determining whether nonwords targets would show repetition priming. To avoid the potential confound that nonword repetition priming would be obscured by a familiarity response bias, the standard lexical decision and naming tasks were modified to make targets unfamiliar. Participants were required to read a target string from right to left (i.e., "ECAF" should be read as "FACE") and then make a response. To examine if priming was based on lexical representations, repetition primes consisted of words when read forwards or backwards (e.g., "face", "ecaf") and nonwords (e.g., "pame", "emap"). Forward and backward primes were used to test if task instruction affected prime encoding. The lexical decision and naming tasks showed the same pattern of results: priming only occurred for forward primes with word targets (e.g., "face-ECAF"). Additional experiments to test if response priming affected the LDT indicated that the lexical status of the prime per se did not affect target responses. These results showed that the encoding of masked primes was unaffected by the novel task instruction and support the view that masked priming is due to the automatic triggering of pre-established computational processes based on stored information.

  4. Comparison of the OxyMask and Venturi mask in the delivery of supplemental oxygen: Pilot study in oxygen-dependent patients

    PubMed Central

    Beecroft, Jaime M; Hanly, Patrick J

    2006-01-01

    BACKGROUND: The OxyMask (Southmedic Inc, Canada) is a new face mask for oxygen delivery that uses a small ‘diffuser’ to concentrate and direct oxygen toward the mouth and nose. The authors hypothesized that this unique design would enable the OxyMask to deliver oxygen more efficiently than a Venturi mask (Hudson RCI, USA) in patients with chronic hypoxemia. METHODS: Oxygen-dependent patients with chronic, stable respiratory disease were recruited to compare the OxyMask and Venturi mask in a randomized, single-blind, cross-over design. Baseline blood oxygen saturation (SaO2) was established breathing room air, followed in a random order by supplemental oxygen through the OxyMask or Venturi mask. Oxygen delivery was titrated to maintain SaO2 4% to 5% and 8% to 9% above baseline for two separate 30 min periods of stable breathing. Oxygen flow rate, partial pressure of inspired and expired oxygen (PO2) and carbon dioxide (PCO2), minute ventilation, heart rate, nasal and oral breathing, SaO2 and transcutaneous PCO2 were collected continuously. The study was repeated following alterations to the OxyMask design, which improved clearance of carbon dioxide. RESULTS: Thirteen patients, aged 28 to 79 years, were studied initially using the original OxyMask. Oxygen flow rate was lower, inspired PO2 was higher and expired PO2 was lower while using the OxyMask. Minute ventilation and inspired and expired PCO2 were significantly higher while using the OxyMask, whereas transcutaneous PCO2, heart rate and the ratio of nasal to oral breathing did not change significantly throughout the study. Following modification of the OxyMask, 13 additional patients, aged 18 to 79 years, were studied using the same protocol. The modified OxyMask provided a higher inspired PO2 at a lower flow rate, without evidence of carbon dioxide retention. CONCLUSIONS: Oxygen is delivered safely and more efficiently by the OxyMask than by the Venturi mask in stable oxygen-dependent patients. PMID:16896425

  5. Mask strategy at International SEMATECH

    NASA Astrophysics Data System (ADS)

    Kimmel, Kurt R.

    2002-08-01

    International SEMATECH (ISMT) is a consortium consisting of 13 leading semiconductor manufacturers from around the globe. Its objective is to develop the infrastructure necessary for its member companies to realize the International Technology Roadmap for Semiconductors (ITRS) through efficiencies of shared development resources and knowledge. The largest area of effort is lithography, recognized as a crucial enabler for microelectronics technology progress. Within the Lithography Division, most of the efforts center on mask-related issues. The development strategy at International SEMATCH will be presented and the interlock of lithography projects clarified. Because of the limited size of the mask production equipment market, the business case is weak for aggressive investment commensurate with the pace of the International Technology Roadmap for Semiconductors. With masks becoming the overwhelming component of lithography cost, new ways of reducing or eliminating mask costs are being explored. Will mask technology survive without a strong business case? Will the mask industry limit the growth of the semiconductor industry? Are advanced masks worth their escalating cost? An analysis of mask cost from the perspective of mask value imparted to the user is presented with examples and generic formulas for the reader to apply independently. A key part to the success for both International SEMATECH and the industry globally will be partnerships on both the local level between mask-maker and mask-user, and the macro level where global collaborations will be necessary to resolve technology development cost challenges.

  6. New mask technology challenges

    NASA Astrophysics Data System (ADS)

    Kimmel, Kurt R.

    2001-09-01

    Mask technology development has accelerated dramatically in recent years from the glacial pace of the last three decades to the rapid and sometimes simultaneous introductions of new wavelengths and mask-based resolution enhancement techniques. The nature of the semiconductor business has also become one driven by time-to-market as an overwhelming factor in capturing market share and profit. These are among the factors that have created enormous stress on the mask industry to produce masks with enhanced capabilities, such as phase-shifting attenuators, sub-resolution assist bars, and optical proximity correction (OPC) features, while maintaining or reducing cost and cycle time. The mask can no longer be considered a commodity item that is purchased form the lowest-cost supplier. Instead, it must now be promoted as an integral part of the technical and business case for a total lithographic solution. Improving partnership between designer, mask-maker, and wafer lithographer will be the harbinger of success in finding a profitable balance of capability, cost, and cycle time. Likewise for equipment infrastructure development, stronger partnership on the international level is necessary to control development cost and mitigate schedule and technical risks.

  7. Coronagraphic mask design using Hermite functions.

    PubMed

    Cagigal, Manuel P; Canales, Vidal F; Valle, Pedro J; Oti, José E

    2009-10-26

    We introduce a stellar coronagraph that uses a coronagraphic mask described by a Hermite function or a combination of them. It allows the detection of exoplanets providing both deep starlight extinction and high angular resolution. This angular resolution depends on the order of the Hermite function used. An analysis of the coronagraph performance is carried out for different even order masks. Numerical simulations of the ideal case, with no phase errors and perfect telescope pointing, show that on-axis starlight is reduced to very low intensity levels corresponding to a gain of at least 25 magnitudes (10(-10) light intensity reduction). The coronagraphic throughput depends on the Hermite function or combination selected. The proposed mask series presents the same advantages of band limited masks along with the benefit of reducing the light diffracted by the mask border thanks to its particular shape. Nevertheless, for direct detection of Earth-like exoplanets it requires the use of adaptive optics facilities for compensating the perturbations introduced by the atmosphere and by the optical system.

  8. PaCO2 measurement in cerebral haemodynamics: face mask or nasal cannulae?

    PubMed

    Minhas, J S; Robinson, T; Panerai, R

    2017-06-22

    PaCO 2 affects cerebral blood flow (CBF) and its regulatory mechanisms, but the effects of CO 2 measurement technique on cerebrovascular parameters are unknown. In order to determine if the two most commonly used approaches, face mask (FM) or nasal cannulae (NC), are interchangeable or not, we tested the hypothesis that the use of FM versus NC does not lead to significant differences in CO 2 -related systemic and cerebrovascular parameters. Recordings of CBF velocity (CBFV), blood pressure (BP), heart rate, and end-tidal CO 2 (EtCO 2 ) were performed in 42 subjects during normocapnia (FM or NC) and 5% CO 2 inhalation (FM) or hyperventilation (NC). Dynamic cerebral autoregulation was assessed with the autoregulation index (ARI), derived by transfer function analysis from the CBFV response to a hypothetical step change in BP. Significant differences in physiological parameters were seen between FM and NC: EtCO 2 (37.40 versus 35.26 mmHg, p  =  0.001) and heart rate (69.6 versus 66.7 bpm, p  =  0.001) respectively. No differences were observed for mean BP, CBFV or the ARI index. Use of FM or NC for measurement of EtCO 2 leads to physiological changes and differences in parameter values that need to be taken into consideration when interpreting and/or comparing results in studies of cerebral haemodynamics.

  9. Odours reduce the magnitude of object substitution masking for matching visual targets in females.

    PubMed

    Robinson, Amanda K; Laning, Julia; Reinhard, Judith; Mattingley, Jason B

    2016-08-01

    Recent evidence suggests that olfactory stimuli can influence early stages of visual processing, but there has been little focus on whether such olfactory-visual interactions convey an advantage in visual object identification. Moreover, despite evidence that some aspects of olfactory perception are superior in females than males, no study to date has examined whether olfactory influences on vision are gender-dependent. We asked whether inhalation of familiar odorants can modulate participants' ability to identify briefly flashed images of matching visual objects under conditions of object substitution masking (OSM). Across two experiments, we had male and female participants (N = 36 in each group) identify masked visual images of odour-related objects (e.g., orange, rose, mint) amongst nonodour-related distracters (e.g., box, watch). In each trial, participants inhaled a single odour that either matched or mismatched the masked, odour-related target. Target detection performance was analysed using a signal detection (d') approach. In females, but not males, matching odours significantly reduced OSM relative to mismatching odours, suggesting that familiar odours can enhance the salience of briefly presented visual objects. We conclude that olfactory cues exert a subtle influence on visual processes by transiently enhancing the salience of matching object representations. The results add to a growing body of literature that points towards consistent gender differences in olfactory perception.

  10. Beam masking to reduce cyclic error in beam launcher of interferometer

    NASA Technical Reports Server (NTRS)

    Ames, Lawrence L. (Inventor); Bell, Raymond Mark (Inventor); Dutta, Kalyan (Inventor)

    2005-01-01

    Embodiments of the present invention are directed to reducing cyclic error in the beam launcher of an interferometer. In one embodiment, an interferometry apparatus comprises a reference beam directed along a reference path, and a measurement beam spatially separated from the reference beam and being directed along a measurement path contacting a measurement object. The reference beam and the measurement beam have a single frequency. At least a portion of the reference beam and at least a portion of the measurement beam overlapping along a common path. One or more masks are disposed in the common path or in the reference path and the measurement path to spatially isolate the reference beam and the measurement beam from one another.

  11. A randomized trial of nasal prong or face mask for respiratory support for preterm newborns.

    PubMed

    McCarthy, Lisa K; Twomey, Anne R; Molloy, Eleanor J; Murphy, John F A; O'Donnell, Colm P F

    2013-08-01

    Resuscitation guidelines recommend that respiratory support should be given to newborns via a face mask (FM) in the delivery room (DR). Respiratory support given to preterm newborns via a single nasal prong (SNP; ie, short nasal tube, nasopharyngeal tube) may be more effective. We wished to determine whether giving respiratory support to preterm newborns with a SNP rather than a FM reduces the rate of intubation in the DR. Infants <31 weeks' gestation were randomized just before delivery to SNP (endotracheal tube shortened to 5 cm) or FM. Randomization was stratified by gestation (<28 weeks, 28-30(+6)). Infants with apnea, respiratory distress, and/or heart rate <100 received positive pressure ventilation with a T-piece. The primary outcome was intubation and mechanical ventilation in the DR. Infants in both groups were intubated for heart rate <100 and/or apnea despite PPV and not solely for surfactant administration. All other aspects of treatment in the DR and NICU were the same. Relevant secondary outcomes were recorded and data were analyzed by using the intention-to-treat principle. One hundred forty-four infants were enrolled. The rate of intubation in the DR was the same in both groups (11/72 [15%] vs 11/72 [15%], P = 1.000]. Infants assigned to SNP had lower SpO2 at 5 minutes and received a higher maximum concentration of oxygen in the DR. There were no significant differences in other secondary outcomes. Giving respiratory support to newborn infants <31 weeks' gestation via a SNP, compared with a FM, did not result in less intubation and ventilation in the DR.

  12. An ERP study of famous face incongruity detection in middle age.

    PubMed

    Chaby, L; Jemel, B; George, N; Renault, B; Fiori, N

    2001-04-01

    Age-related changes in famous face incongruity detection were examined in middle-aged (mean = 50.6) and young (mean = 24.8) subjects. Behavioral and ERP responses were recorded while subjects, after a presentation of a "prime face" (a famous person with the eyes masked), had to decide whether the following "test face" was completed with its authentic eyes (congruent) or with other eyes (incongruent). The principal effects of advancing age were (1) behavioral difficulties in discriminating between incongruent and congruent faces; (2) a reduced N400 effect due to N400 enhancement for both congruent and incongruent faces; (3) a latency increase of both N400 and P600 components. ERPs to primes (face encoding) were not affected by aging. These results are interpreted in terms of early signs of aging. Copyright 2001 Academic Press.

  13. The automatic back-check mechanism of mask tooling database and automatic transmission of mask tooling data

    NASA Astrophysics Data System (ADS)

    Xu, Zhe; Peng, M. G.; Tu, Lin Hsin; Lee, Cedric; Lin, J. K.; Jan, Jian Feng; Yin, Alb; Wang, Pei

    2006-10-01

    Nowadays, most foundries have paid more and more attention in order to reduce the CD width. Although the lithography technologies have developed drastically, mask data accuracy is still a big challenge than before. Besides, mask (reticle) price also goes up drastically such that data accuracy needs more special treatments.We've developed a system called eFDMS to guarantee the mask data accuracy. EFDMS is developed to do the automatic back-check of mask tooling database and the data transmission of mask tooling. We integrate our own EFDMS systems to engage with the standard mask tooling system K2 so that the upriver and the downriver processes of the mask tooling main body K2 can perform smoothly and correctly with anticipation. The competition in IC marketplace is changing from high-tech process to lower-price gradually. How to control the reduction of the products' cost more plays a significant role in foundries. Before the violent competition's drawing nearer, we should prepare the cost task ahead of time.

  14. The efficacy of three different mask styles on a PAP titration night.

    PubMed

    Ebben, Matthew R; Oyegbile, Temitayo; Pollak, Charles P

    2012-06-01

    This study compared the efficacy of three different masks, nasal pillows, nasal masks and full face (oronasal) masks, during a single night of titration with continuous positive airway pressure (CPAP). Fifty five subjects that included men (n=33) and women (n=22) were randomly assigned to one of three masks and underwent a routine titration with incremental CPAP applied through the different masks. CPAP applied through the nasal pillows and nasal mask was equally effective in treating mild, moderate, and severe sleep apnea. However, CPAP applied through the oronasal mask required a significantly higher pressure compared to nasal masks to treat moderately severe (2.8 cm of H(2)O ± 2.1 SD) and severe (6.0 cm of H(2)O ± 3.2 SD) obstructive sleep apnea. CPAP applied with either nasal mask was effective in treating mild, moderate, and severe sleep apnea. The oronasal mask required significantly higher pressures in subjects with moderate to severe disease. Therefore, when changing from a nasal to an oronasal mask, a repeat titration is required to ensure effective treatment of sleep apnea, especially in patients with moderate to severe disease. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Monaural informational masking release in children and adults

    NASA Astrophysics Data System (ADS)

    Buss, Emily; Hall, Joseph W.; Grose, John H.

    2004-05-01

    Informational masking refers to an elevation in signal threshold due to stimulus uncertainty, rather than to energetic masking. This study assessed informational masking and utilization of cues to reduce that masking in children aged 5-9 and adults. We used a manipulation introduced by Kidd et al. [J. Acoust. Soc. Am. 95, 3475-3480 (1994)] in which the signal was a train of eight consecutive tone bursts, each at 1 kHz and 60 ms in duration. Maskers were comprised of a pair of synchronous tone-burst trains whose frequencies were selected from the range spanning 0.2-5 kHz, with a protected region 851-1175 Hz. In the reference condition, where informational masking is pronounced, these maskers were eight bursts and had a fixed frequency within each interval, with new frequencies chosen randomly prior to each interval. Two conditions of masking release were tested: random frequency selection for each masker burst and a masker leading fringe of two additional 60-ms bursts. Both children and adults showed a significant informational masking effect, with children showing a larger effect. Both groups also showed significant release from masking, though initial results suggest that this may have been reduced in the youngest children. [Work supported by NIH, RO1 DC00397.

  16. Object Substitution Masking: When Does Mask Preview Work?

    ERIC Educational Resources Information Center

    Lim, Stephen Wee Hun; Chua, Fook K.

    2008-01-01

    When a target is enclosed by a 4-dot mask that persists after the target disappears, target identification is worse than it is when the mask terminates with the target. This masking effect is attributed to object substitution masking (OSM). Previewing the mask, however, attenuates OSM. This study investigated specific conditions under which mask…

  17. The magic of 4X mask reduction

    NASA Astrophysics Data System (ADS)

    Lercel, Michael

    2006-06-01

    Although changing the mask reduction factor from 4X to a larger value offers several technical advantages, previous attempts to enact this change have not identified enough clear technical advantages to overcome the impact to productivity. Improvements in mask manufacturing, mask polarization effects, and optics cost have not been thought to be sufficient reason to accept a reduced throughput and field size. This paper summarizes the latest workshop and discussion revisiting the mask reduction factor for 32nm half-pitch lithography with hyper-numerical aperture (NA) optical or extreme ultraviolet lithography (EUVL). The workshop consensus was strongly in favor of maintaining the current magnification ratio and field size as long as mask costs can be contained.

  18. How Does Target Duration Affect Object Substitution Masking?

    ERIC Educational Resources Information Center

    Gellatly, Angus; Pilling, Michael; Carter, Wakefield; Guest, Duncan

    2010-01-01

    Object substitution masking (OSM) is typically studied using a brief search display. The target item may be indicated by a cue/mask surrounding but not overlapping it. Report of the target is reduced when mask offset trails target offset rather than being simultaneous with it. We report 5 experiments investigating whether OSM can be obtained if…

  19. Effects of immobilization mask material on surface dose

    PubMed Central

    Hadley, Scott W.; Kelly, Robin; Lam, Kwok

    2005-01-01

    This work investigates the increase in surface dose caused by thermoplastic masks used for patient positioning and immobilization. A thermoplastic mask is custom fit by stretching a heated mask over the patient at the time of treatment simulation. This mask is then used at treatment to increase the reproducibility of the patient position. The skin sparing effect of mega‐voltage X‐ray beams can be reduced when the patient's skin surface is under the mask material. The sheet of thermoplastic mask has holes to reduce this effect and is available from one manufacturer with two different sizes of holes, one larger than the other. This work investigates the increase in surface dose caused by the mask material and quantifies the difference between the two samples of masks available. The change in the dose buildup was measured using an Attix parallel plate chamber by measuring tissue maximum ratios (TMRs) using solid water. Measurements were made with and without the mask material on the surface of the solid water for 6‐MV and 15‐MV X‐ray beams. The effective thickness of equivalent water was estimated from the TMR curves, and the increase in surface dose was estimated. The buildup effect was measured to be equivalent to 2.2 mm to 0.6 mm for masks that have been stretched by different amounts. The surface dose was estimated to change from 16% and 12% for 6 MV and 15 MV, respectively, to 27% to 61% for 6 MV and 18% to 40% for 15 MV with the mask samples. PACS number: 87.53.Dq PMID:15770192

  20. Quartz 9-inch size mask blanks for ArF PSM (Phase Shift Mask)

    NASA Astrophysics Data System (ADS)

    Harashima, Noriyuki; Isozaki, Tatsuya; Kawanishi, Arata; Kanai, Shuichiro; Kageyama, Kagehiro; Iso, Hiroyuki; Chishima, Tatsuya

    2017-07-01

    Semiconductor technology nodes are steadily miniaturizing. On the other hand, various efforts have been made to reduce costs, mass production lines have shifted from 200 mmφ of Si wafer to 300 mmφ, and technology development of Si wafer 450 mmφ is also in progress. As a photomask, 6-inch size binary Cr mask has been used for many years, but in recent years, the use of 9-inch binary Cr masks for Proximity Lithography Process in automotive applications, MEMS, packages, etc. has increased, and cost reduction has been taken. Since the miniaturization will progress in the above applications in the future, products corresponding to miniaturization are also desired in 9-inch photomasks. The high grade Cr - binary mask blanks used in proximity exposure process, there is a prospect of being able to use it by ULVAC COATING CORPORATION's tireless research. As further demands for miniaturization, KrF and ArF Lithography Process, which are used for steppers and scanners , there are also a demand for 9-inch size Mask Blanks. In ULVAC COATING CORPORATION, we developed a 9 - inch size KrF PSM mask Blanks prototype in 2016 and proposed a new high grade 9 - inch photomask. This time, we have further investigated and developed 9-inch size ArF PSM Mask Blanks corresponding to ArF Lithography Process, so we report it.

  1. Mask-to-wafer alignment system

    DOEpatents

    Sweatt, William C.; Tichenor, Daniel A.; Haney, Steven J.

    2003-11-04

    A modified beam splitter that has a hole pattern that is symmetric in one axis and anti-symmetric in the other can be employed in a mask-to-wafer alignment device. The device is particularly suited for rough alignment using visible light. The modified beam splitter transmits and reflects light from a source of electromagnetic radiation and it includes a substrate that has a first surface facing the source of electromagnetic radiation and second surface that is reflective of said electromagnetic radiation. The substrate defines a hole pattern about a central line of the substrate. In operation, an input beam from a camera is directed toward the modified beam splitter and the light from the camera that passes through the holes illuminates the reticle on the wafer. The light beam from the camera also projects an image of a corresponding reticle pattern that is formed on the mask surface of the that is positioned downstream from the camera. Alignment can be accomplished by detecting the radiation that is reflected from the second surface of the modified beam splitter since the reflected radiation contains both the image of the pattern from the mask and a corresponding pattern on the wafer.

  2. Sex differences in neural responses to subliminal sad and happy faces in healthy individuals: Implications for depression.

    PubMed

    Victor, Teresa A; Drevets, Wayne C; Misaki, Masaya; Bodurka, Jerzy; Savitz, Jonathan

    2017-01-02

    Twice as many women as men suffer from mood and anxiety disorders, yet the biological underpinnings of this phenomenon have been understudied and remain unclear. We and others have shown that the hemodynamic response to subliminally presented sad or happy faces during functional MRI (fMRI) is a robust biomarker for the attentional bias toward negative information classically observed in major depression. Here we used fMRI to compare the performance of healthy females (n = 28) and healthy males (n = 28) on a backward masking task using a fast event-related design with gradient-recalled, echoplanar imaging with sensitivity encoding. The image data were compared across groups using a region-of-interest analysis with small-volume correction to control for multiple testing (P corrected  < 0.05, cluster size ≥ 20 voxels). Notably, compared with males, females showed greater BOLD activity in the subgenual anterior cingulate cortex (sgACC) and the right hippocampus when viewing masked sad vs. masked happy faces. Furthermore, females displayed reduced BOLD activity in the right pregenual ACC and left amygdala when viewing masked happy vs. masked neutral faces. Given that we have previously reported similar findings for depressed participants compared with healthy controls (regardless of gender), our results raise the possibility that on average healthy females show subtle emotional processing biases that conceivably reflect a subgroup of women predisposed to depression. Nevertheless, we note that the differences between males and females were small and derived from region-of-interest rather than voxelwise analyses. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Marquardt’s Facial Golden Decagon Mask and Its Fitness with South Indian Facial Traits

    PubMed Central

    Gandikota, Chandra Sekhar; Yadagiri, Poornima K; Manne, Ranjit; Juvvadi, Shubhaker Rao; Farah, Tamkeen; Vattipelli, Shilpa; Gumbelli, Sangeetha

    2016-01-01

    Introduction The mathematical ratio of 1:1.618 which is famously known as golden ratio seems to appear recurrently in beautiful things in nature as well as in other things that are seen as beautiful. Dr. Marquardt developed a facial golden mask that contains and includes all of the one-dimensional and two-dimensional geometric golden elements formed from the golden ratio and he claimed that beauty is universal, beautiful faces conforms to the facial golden mask regardless of sex and race. Aim The purpose of this study was to evaluate the goodness of fit of the golden facial mask with the South Indian facial traits. Materials and Methods A total of 150 subjects (75 males & 75 females) with attractive faces were selected with cephalometric orthodontic standards of a skeletal class I relation. The facial aesthetics was confirmed by the aesthetic evaluation of the frontal photographs of the subjects by a panel of ten evaluators including five orthodontists and five maxillofacial surgeons. The well-proportioned photographs were superimposed with the Golden mask along the reference lines, to evaluate the goodness of fit. Results South Indian males and females invariably show a wider inter-zygomatic and inter-gonial width than the golden mask. Most of the South Indian females and males show decreased mid-facial height compared to the golden mask, while the total facial height is more or less equal to the golden mask. Conclusion Ethnic or individual discrepancies cannot be totally ignored as in our study the mask did not fit exactly with the South Indian facial traits but, the beauty ratios came closer to those of the mask. To overcome this difficulty, there is a need to develop variants of golden facial mask for different ethnic groups. PMID:27190951

  4. Model-based virtual VSB mask writer verification for efficient mask error checking and optimization prior to MDP

    NASA Astrophysics Data System (ADS)

    Pack, Robert C.; Standiford, Keith; Lukanc, Todd; Ning, Guo Xiang; Verma, Piyush; Batarseh, Fadi; Chua, Gek Soon; Fujimura, Akira; Pang, Linyong

    2014-10-01

    A methodology is described wherein a calibrated model-based `Virtual' Variable Shaped Beam (VSB) mask writer process simulator is used to accurately verify complex Optical Proximity Correction (OPC) and Inverse Lithography Technology (ILT) mask designs prior to Mask Data Preparation (MDP) and mask fabrication. This type of verification addresses physical effects which occur in mask writing that may impact lithographic printing fidelity and variability. The work described here is motivated by requirements for extreme accuracy and control of variations for today's most demanding IC products. These extreme demands necessitate careful and detailed analysis of all potential sources of uncompensated error or variation and extreme control of these at each stage of the integrated OPC/ MDP/ Mask/ silicon lithography flow. The important potential sources of variation we focus on here originate on the basis of VSB mask writer physics and other errors inherent in the mask writing process. The deposited electron beam dose distribution may be examined in a manner similar to optical lithography aerial image analysis and image edge log-slope analysis. This approach enables one to catch, grade, and mitigate problems early and thus reduce the likelihood for costly long-loop iterations between OPC, MDP, and wafer fabrication flows. It moreover describes how to detect regions of a layout or mask where hotspots may occur or where the robustness to intrinsic variations may be improved by modification to the OPC, choice of mask technology, or by judicious design of VSB shots and dose assignment.

  5. Brightness masking is modulated by disparity structure.

    PubMed

    Pelekanos, Vassilis; Ban, Hiroshi; Welchman, Andrew E

    2015-05-01

    The luminance contrast at the borders of a surface strongly influences surface's apparent brightness, as demonstrated by a number of classic visual illusions. Such phenomena are compatible with a propagation mechanism believed to spread contrast information from borders to the interior. This process is disrupted by masking, where the perceived brightness of a target is reduced by the brief presentation of a mask (Paradiso & Nakayama, 1991), but the exact visual stage that this happens remains unclear. In the present study, we examined whether brightness masking occurs at a monocular-, or a binocular-level of the visual hierarchy. We used backward masking, whereby a briefly presented target stimulus is disrupted by a mask coming soon afterwards, to show that brightness masking is affected by binocular stages of the visual processing. We manipulated the 3-D configurations (slant direction) of the target and mask and measured the differential disruption that masking causes on brightness estimation. We found that the masking effect was weaker when stimuli had a different slant. We suggest that brightness masking is partly mediated by mid-level neuronal mechanisms, at a stage where binocular disparity edge structure has been extracted. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Barriers to mask wearing for influenza-like illnesses among urban Hispanic households.

    PubMed

    Ferng, Yu-hui; Wong-McLoughlin, Jennifer; Barrett, Angela; Currie, Leanne; Larson, Elaine

    2011-01-01

    To identify barriers to mask wearing and to examine the factors associated with the willingness to wear masks among households. We used data sources from a study assessing the impact of 3 nonpharmaceutical interventions on the rates of influenza: exit interviews; home visits with a subset of the mask group; and a focus group. Risk perception score, univariate analysis, and logistic regression were conducted to identify the characteristics and predictors of mask use. Thematic barriers to mask wearing were identified from qualitative data obtained at home visits and focus group. Respondents from the mask group, when compared with the nonmask group, demonstrated higher risk perception scores concerning influenza (maximum score: 60, means: 37.6 and 30.2, p<.001) and increased perception of effectiveness of mask wearing (maximum score: 10, means: 7.8 and 7.3, p=.043). There was no significant association between demographic, attitudinal, or knowledge variables and adherence to wearing masks. Thematic barriers were identified such as social acceptability of mask use, comfort and fit, and perception of the risk/need for masks. Face masks may not be an effective intervention for seasonal or pandemic influenza unless the risk perception of influenza is high. Dissemination of culturally appropriate mask use information by health authorities and providers must be emphasized when educating the public. © 2010 Wiley Periodicals, Inc.

  7. Comparison of Comfort and Effectiveness of Total Face Mask and Oronasal Mask in Noninvasive Positive Pressure Ventilation in Patients with Acute Respiratory Failure: A Clinical Trial.

    PubMed

    Sadeghi, Somayeh; Fakharian, Atefeh; Nasri, Peiman; Kiani, Arda

    2017-01-01

    Background . There is a growing controversy about the use of oronasal masks (ONM) or total facemask (TFM) in noninvasive positive pressure ventilation (NPPV), so we designed a trial to compare the uses of these two masks in terms of effectiveness and comfort. Methods . Between February and November 2014, a total of 48 patients with respiratory failure were studied. Patients were randomized to receive NPPV via ONM or TFM. Data were recorded at 60 minutes and six and 24 hours after intervention. Patient comfort was assessed using a questionnaire. Data were analyzed using t -test and chi-square test. Repeated measures ANOVA and Mann-Whitney U test were used to compare clinical and laboratory data. Results . There were no differences in venous blood gas (VBG) values between the two groups ( P > 0.05). However, at six hours, TFM was much more effective in reducing the partial pressure of carbon dioxide (PCO2) ( P = 0.04). Patient comfort and acceptance were statistically similar in both groups ( P > 0.05). Total time of NPPV was also similar in the two groups ( P > 0.05). Conclusions . TFM was superior to ONM in acute phase of respiratory failure but not once the patients were out of acute phase.

  8. Clean induced feature CD shift of EUV mask

    NASA Astrophysics Data System (ADS)

    Nesládek, Pavel; Schedel, Thorsten; Bender, Markus

    2016-05-01

    EUV developed in the last decade to the most promising <7nm technology candidate. Defects are considered to be one of the most critical issues of the EUV mask. There are several contributors which make the EUV mask so different from the optical one. First one is the significantly more complicated mask stack consisting currently of 40 Mo/Si double layers, covered by Ru capping layer and TaN/TaO absorber/anti-reflective coating on top of the front face of the mask. Backside is in contrary to optical mask covered as well by conductive layer consisting of Cr or CrN. Second contributor is the fact that EUV mask is currently in contrary to optical mask not yet equipped with sealed pellicle, leading to much higher risk of mask contamination. Third reason is use of EUV mask in vacuum, possibly leading to deposition of vacuum contaminants on the EUV mask surface. Latter reason in combination with tight requirements on backside cleanliness lead to the request of frequent recleaning of the EUV mask, in order to sustain mask lifetime similar to that of optical mask. Mask cleaning process alters slightly the surface of any mask - binary COG mask, as well as phase shift mask of any type and naturally also of the EUV mask as well. In case of optical masks the changes are almost negligible, as the mask is exposed to max. 10-20 re-cleans within its life time. These modifications can be expressed in terms of different specified parameters, e.g. CD shift, phase/trans shift, change of the surface roughness etc. The CD shift, expressed as thinning (or exceptionally thickening) of the dark features on the mask is typically in order of magnitude 0.1nm per process run, which is completely acceptable for optical mask. Projected on the lifetime of EUV mask, assuming 100 clean process cycles, this will lead to CD change of about 10nm. For this reason the requirements for EUV mask cleaning are significantly tighter, << 0.1 nm per process run. This task will look even more challenging, when

  9. Effective EUVL mask cleaning technology solutions for mask manufacturing and in-fab mask maintenance

    NASA Astrophysics Data System (ADS)

    Dietze, Uwe; Dress, Peter; Waehler, Tobias; Singh, Sherjang; Jonckheere, Rik; Baudemprez, Bart

    2011-03-01

    Extreme Ultraviolet Lithography (EUVL) is considered the leading lithography technology choice for semiconductor devices at 16nm HP node and beyond. However, before EUV Lithography can enter into High Volume Manufacturing (HVM) of advanced semiconductor devices, the ability to guarantee mask integrity at point-of-exposure must be established. Highly efficient, damage free mask cleaning plays a critical role during the mask manufacturing cycle and throughout the life of the mask, where the absence of a pellicle to protect the EUV mask increases the risk of contamination during storage, handling and use. In this paper, we will present effective EUVL mask cleaning technology solutions for mask manufacturing and in-fab mask maintenance, which employs an intelligent, holistic approach to maximize Mean Time Between Cleans (MBTC) and extend the useful life span of the reticle. The data presented will demonstrate the protection of the capping and absorber layers, preservation of pattern integrity as well as optical and mechanical properties to avoid unpredictable CD-linewidth and overlay shifts. Experiments were performed on EUV blanks and pattern masks using various process conditions. Conditions showing high particle removal efficiency (PRE) and minimum surface layer impact were then selected for durability studies. Surface layer impact was evaluated over multiple cleaning cycles by means of UV reflectivity metrology XPS analysis and wafer prints. Experimental results were compared to computational models. Mask life time predictions where made using the same computational models. The paper will provide a generic overview of the cleaning sequence which yielded best results, but will also provide recommendations for an efficient in-fab mask maintenance scheme, addressing handling, storage, cleaning and inspection.

  10. Challenges in evaluating PM concentration levels, commuting exposure, and mask efficacy in reducing PM exposure in growing, urban communities in a developing country.

    PubMed

    Patel, Disa; Shibata, Tomoyuki; Wilson, James; Maidin, Alimin

    2016-02-01

    Particulate matter (PM) contributes to an increased risk of respiratory and cardiovascular illnesses, cancer, and preterm birth complications. This project assessed PM exposure in Eastern Indonesia's largest city, where air quality has not been comprehensively monitored. We examined the efficacy of wearing masks as an individual intervention effort to reduce in-transit PM exposures. Handheld particulate counters were used to investigate ambient air quality for spatial analysis, as well as the differences in exposure to PM2.5 and PM10 (μg/m(3)) by different transportation methods [e.g. motorcycle (n=97), pete-pete (n=53), and car (n=55); note: n=1 means 1m(3) of air sample]. Mask efficacy to reduce PM exposure was evaluated [e.g. surgical masks (n=39), bandanas (n=52), and motorcycle masks (n=39)]. A Monte Carlo simulation was used to provide a range of uncertainty in exposure assessment. Overall PM10 levels (91±124 μg/m(3)) were elevated compared to the World Health Organization (WHO)'s 24-hour air quality guideline (50 μg/m(3)). While average PM2.5 levels (9±14 μg/m(3)) were below the WHO's guideline (25 μg/m(3)), measurements up to 139 μg/m(3) were observed. Compared to cars, average motorcycle and pete-pete PM exposures were four and three times higher for PM2.5, and 13 and 10 times higher for PM10, respectively. Only surgical masks were consistent in lowering PM2.5 and PM10 (p<0.01). Young children (≤5) were the most vulnerable age group, and could not reach the safe dosage even when wearing surgical masks. Individual interventions can effectively reduce individual PM exposures; however, policy interventions will be needed to improve the overall air quality and create safer transportation. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Extraction and utilization of the repeating patterns for CP writing in mask making

    NASA Astrophysics Data System (ADS)

    Shoji, Masahiro; Inoue, Tadao; Yamabe, Masaki

    2010-05-01

    In May 2006, the Mask Design, Drawing, and Inspection Technology Research Department (Mask D2I) at the Association of Super-Advanced Electronics Technologies (ASET) launched a 4-year program for reducing mask manufacturing cost and TAT by concurrent optimization of Mask Data Preparation (MDP), mask writing, and mask inspection [1]. Figure 1 shows an outline of the project at Mask D2I at ASET. As one of the tasks being pursued at the Mask Design Data Technology Research Laboratory we have evaluated the effect of reducing the writing shot counts by utilizing the repeating patterns, and that showed positive impact on mask making by using CP writing. During the past four years, we have developed a software to extract repeating patterns from fractured OPCed mask data and have evaluated the efficiency of reducing the writing shot counts using the repeating patterns with this software. In this evaluation, we have used many actual device production data obtained from the member companies of Mask D2I. To the extraction software, we added new functions for extracting common repeating patterns from a set of multiple masks, and studied how this step affects the ratio of reducing the shot counts in comparison to the case of utilization of the repeating patterns for single mask. We have also developed a software that uses the result of extracting repeating patterns and prepares writing-data for the MCC/CP writing system which has been developed at the Mask Writing Equipment Technology Research Laboratory. With this software, we have examined how EB proximity effect on CP writing affects in reducing the shot count where CP shots with large CD errors have to be divided into VSB shots. In this paper we will report on making common CP mask from a set of multiple actual device data by using these software, and will also report on the results of CP writing and calculation of writing-TAT by MCC/CP writing system.

  12. Flavored Anesthetic Masks for Inhalational Induction in Children.

    PubMed

    Gupta, Aakriti; Mathew, Preethy Joseph; Bhardwaj, Neerja

    2017-10-01

    To evaluate the clinical efficacy of masking the odor of inhalational agents using fruit flavors on the anxiety behavior and compliance of children for inhalational induction. A prospective randomized double blind, placebo controlled study was conducted on 60 unpremedicated children in the age group of 4-12 y. Thirty children received anesthetic masks smeared with a flavor of child's choice while the other 30 children were induced using masks without flavor. Anxiety was assessed using modified Yale Pre-operative Anxiety Scale (mYPAS) in the pre-op room and during inhalational induction. Mask acceptance was graded by Induction Compliance Checklist (ICC). The cost-effectiveness of flavored anesthetic masks was compared to that of commercially available pre-scented masks. The baseline anxiety in the two groups was comparable. The number of children demonstrating high levels of anxiety at anesthetic induction was similar in flavored and non-flavored mask groups (p 0.45). The compliance to mask induction was also equally good (p 0.99). The authors found significant difference in the cost of flavored mask (INR 56.45 per mask) as compared to commercially available pre-scented masks (INR 660 per mask). The authors observed a placebo effect that reduced the pre-op anxiety in the control group which probably made the quality of induction equivalent with flavored and non-flavored masks. Therefore, using a flavored anesthetic mask is cost-effective than using a commercially available pre-scented mask.

  13. Development of movable mask system to cope with high beam current

    NASA Astrophysics Data System (ADS)

    Suetsugu, Y.; Shibata, K.; Sanami, T.; Kageyama, T.; Takeuchi, Y.

    2003-07-01

    The KEK B factory (KEKB), a high current electron-positron collider, has a movable mask (or collimator) system to reduce the background noise in the BELLE detector coming from spent particles. The early movable masks, however, had severe problems of heating, arcing, and vacuum leaks over the stored beam current of several hundred mA. The cause is intense trapped higher order modes (HOMs) excited at the mask head, where the cross section of the beam chamber changed drastically. The mask head, made of copper-tungsten alloy or pure copper, was frequently damaged by hitting of the high energy beam at the same time. Since the problems of the mask were revealed, several kinds of improved masks have been designed employing rf technologies in dealing with the HOM and installed to the ring step by step. Much progress has come from adopting a trapped-mode free structure, where the mask was a bent chamber itself. Recently the further improved mask with a reduced HOM design or HOM dampers was developed to suppress the heating of vacuum components near the mask due to the HOM traveling from the mask. To avoid damage to the mask head, on the other hand, a titanium mask head was tried. The latest masks are working as expected now at the stored beam current of 1.5 A. Presented are the problems and experiences on the movable mask system for the KEKB, which are characteristic of and common in a high intensity accelerator.

  14. Emotion potentiates response activation and inhibition in masked priming

    PubMed Central

    Bocanegra, Bruno R.; Zeelenberg, René

    2012-01-01

    Previous studies have shown that emotion can have 2-fold effects on perception. At the object-level, emotional stimuli benefit from a stimulus-specific boost in visual attention at the relative expense of competing stimuli. At the visual feature-level, recent findings indicate that emotion may inhibit the processing of small visual details and facilitate the processing of coarse visual features. In the present study, we investigated whether emotion can boost the activation and inhibition of automatic motor responses that are generated prior to overt perception. To investigate this, we tested whether an emotional cue affects covert motor responses in a masked priming task. We used a masked priming paradigm in which participants responded to target arrows that were preceded by invisible congruent or incongruent prime arrows. In the standard paradigm, participants react faster, and commit fewer errors responding to the directionality of target arrows, when they are preceded by congruent vs. incongruent masked prime arrows (positive congruency effect, PCE). However, as prime-target SOAs increase, this effect reverses (negative congruency effect, NCE). These findings have been explained as evidence for an initial activation and a subsequent inhibition of a partial response elicited by the masked prime arrow. Our results show that the presentation of fearful face cues, compared to neutral face cues, increased the size of both the PCE and NCE, despite the fact that the primes were invisible. This is the first demonstration that emotion prepares an individual's visuomotor system for automatic activation and inhibition of motor responses in the absence of visual awareness. PMID:23162447

  15. Emotion potentiates response activation and inhibition in masked priming.

    PubMed

    Bocanegra, Bruno R; Zeelenberg, René

    2012-01-01

    Previous studies have shown that emotion can have 2-fold effects on perception. At the object-level, emotional stimuli benefit from a stimulus-specific boost in visual attention at the relative expense of competing stimuli. At the visual feature-level, recent findings indicate that emotion may inhibit the processing of small visual details and facilitate the processing of coarse visual features. In the present study, we investigated whether emotion can boost the activation and inhibition of automatic motor responses that are generated prior to overt perception. To investigate this, we tested whether an emotional cue affects covert motor responses in a masked priming task. We used a masked priming paradigm in which participants responded to target arrows that were preceded by invisible congruent or incongruent prime arrows. In the standard paradigm, participants react faster, and commit fewer errors responding to the directionality of target arrows, when they are preceded by congruent vs. incongruent masked prime arrows (positive congruency effect, PCE). However, as prime-target SOAs increase, this effect reverses (negative congruency effect, NCE). These findings have been explained as evidence for an initial activation and a subsequent inhibition of a partial response elicited by the masked prime arrow. Our results show that the presentation of fearful face cues, compared to neutral face cues, increased the size of both the PCE and NCE, despite the fact that the primes were invisible. This is the first demonstration that emotion prepares an individual's visuomotor system for automatic activation and inhibition of motor responses in the absence of visual awareness.

  16. Effectiveness of three just-in-time training modalities for N-95 mask fit testing.

    PubMed

    Jones, David; Stoler, Genevieve; Suyama, Joe

    2013-01-01

    To compare and contrast three different training modalities for fit testing N-95 respirator face masks. Block randomized interventional study. Urban university. Two hundred eighty-nine medical students. Students were randomly assigned to video, lecture, or slide show to evaluate the effectiveness of the methods for fit testing large groups of people. Ease of fit and success of fit for each instructional technique. Mask 1 was a Kimberly-Clark duckbill N-95 respirator mask, and mask 2 was a 3M™ carpenters N-95 respirator mask. "Ease of fit" was defined as the ability to successfully don a mask in less than 30 seconds. "Success of fit" was defined as the ability to correctly don a mask in one try. There were no statistical differences by training modality for either mask regarding ease of fit or success of fit. There were no differences among video presentation, small group demonstration, and self-directed slide show just-in-time training modalities for ease of fit or success of fit N-95 respirator mask fitting. Further study is needed to explore more effective fit training modalities.

  17. Effectiveness of surgical masks against influenza bioaerosols.

    PubMed

    Makison Booth, C; Clayton, M; Crook, B; Gawn, J M

    2013-05-01

    Most surgical masks are not certified for use as respiratory protective devices (RPDs). In the event of an influenza pandemic, logistical and practical implications such as storage and fit testing will restrict the use of RPDs to certain high-risk procedures that are likely to generate large amounts of infectious bioaerosols. Studies have shown that in such circumstances increased numbers of surgical masks are worn, but the protection afforded to the wearer by a surgical mask against infectious aerosols is not well understood. To develop and apply a method for assessing the protection afforded by surgical masks against a bioaerosol challenge. A dummy test head attached to a breathing simulator was used to test the performance of surgical masks against a viral challenge. Several designs of surgical masks commonly used in the UK healthcare sector were evaluated by measuring levels of inert particles and live aerosolised influenza virus in the air, from in front of and behind each mask. Live influenza virus was measurable from the air behind all surgical masks tested. The data indicate that a surgical mask will reduce exposure to aerosolised infectious influenza virus; reductions ranged from 1.1- to 55-fold (average 6-fold), depending on the design of the mask. We describe a workable method to evaluate the protective efficacy of surgical masks and RPDs against a relevant aerosolised biological challenge. The results demonstrated limitations of surgical masks in this context, although they are to some extent protective. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  18. A mask manufacturer's perspective on maskless lithography

    NASA Astrophysics Data System (ADS)

    Buck, Peter; Biechler, Charles; Kalk, Franklin

    2005-11-01

    Maskless Lithography (ML2) is again being considered for use in mainstream CMOS IC manufacturing. Sessions at technical conferences are being devoted to ML2. A multitude of new companies have been formed in the last several years to apply new concepts to breaking the throughput barrier that has in the past prevented ML2 from achieving the cost and cycle time performance necessary to become economically viable, except in rare cases. Has Maskless Lithography's (we used to call it "Direct Write Lithography") time really come? If so, what is the expected impact on the mask manufacturer and does it matter? The lithography tools used today in mask manufacturing are similar in concept to ML2 except for scale, both in throughput and feature size. These mask tools produce highly accurate lithographic images directly from electronic pattern files, perform multi-layer overlay, and mix-n-match across multiple tools, tool types and sites. Mask manufacturers are already accustomed to the ultimate low volume - one substrate per design layer. In order to achieve the economically required throughput, proposed ML2 systems eliminate or greatly reduce some of the functions that are the source of the mask writer's accuracy. Can these ML2 systems meet the demanding lithographic requirements without these functions? ML2 may eliminate the reticle but many of the processes and procedures performed today by the mask manufacturer are still required. Examples include the increasingly complex mask data preparation step and the verification performed to ensure that the pattern on the reticle is accurately representing the design intent. The error sources that are fixed on a reticle are variable with time on an ML2 system. It has been proposed that if ML2 is successful it will become uneconomical to be in the mask business - that ML2, by taking the high profit masks will take all profitability out of mask manufacturing and thereby endanger the entire semiconductor industry. Others suggest that a

  19. Clay Mask Workshop

    ERIC Educational Resources Information Center

    Gamble, David L.

    2012-01-01

    Masks can represent so many things, such as emotions (happy, sad, fearful) and power. The familiar "comedy and tragedy" masks, derived from ancient Greek theater, are just one example from mask history. Death masks from the ancient Egyptians influenced the ancient Romans into creating similar masks for their departed. Masks can represent many…

  20. venice: Mask utility

    NASA Astrophysics Data System (ADS)

    Coupon, Jean

    2018-02-01

    venice reads a mask file (DS9 or fits type) and a catalogue of objects (ascii or fits type) to create a pixelized mask, find objects inside/outside a mask, or generate a random catalogue of objects inside/outside a mask. The program reads the mask file and checks if a point, giving its coordinates, is inside or outside the mask, i.e. inside or outside at least one polygon of the mask.

  1. Individuation training with other-race faces reduces preschoolers' implicit racial bias: a link between perceptual and social representation of faces in children.

    PubMed

    Xiao, Wen S; Fu, Genyue; Quinn, Paul C; Qin, Jinliang; Tanaka, James W; Pascalis, Olivier; Lee, Kang

    2015-07-01

    The present study examined whether perceptual individuation training with other-race faces could reduce preschool children's implicit racial bias. We used an 'angry = outgroup' paradigm to measure Chinese children's implicit racial bias against African individuals before and after training. In Experiment 1, children between 4 and 6 years were presented with angry or happy racially ambiguous faces that were morphed between Chinese and African faces. Initially, Chinese children demonstrated implicit racial bias: they categorized happy racially ambiguous faces as own-race (Chinese) and angry racially ambiguous faces as other-race (African). Then, the children participated in a training session where they learned to individuate African faces. Children's implicit racial bias was significantly reduced after training relative to that before training. Experiment 2 used the same procedure as Experiment 1, except that Chinese children were trained with own-race Chinese faces. These children did not display a significant reduction in implicit racial bias. Our results demonstrate that early implicit racial bias can be reduced by presenting children with other-race face individuation training, and support a linkage between perceptual and social representations of face information in children. © 2014 John Wiley & Sons Ltd.

  2. Assessment of molecular contamination in mask pod

    NASA Astrophysics Data System (ADS)

    Foray, Jean Marie; Dejaune, Patrice; Sergent, Pierre; Gough, Stuart; Cheung, D.; Davenet, Magali; Favre, Arnaud; Rude, C.; Trautmann, T.; Tissier, Michel; Fontaine, H.; Veillerot, M.; Avary, K.; Hollein, I.; Lerit, R.

    2008-04-01

    Context/ study Motivation: Contamination and especially Airbone Molecular Contamination (AMC) is a critical issue for mask material flow with a severe and fairly unpredictable risk of induced contamination and damages especially for 193 nm lithography. It is therefore essential to measure, to understand and then try to reduce AMC in mask environment. Mask material flow was studied in a global approach by a pool of European partners, especially within the frame of European MEDEA+ project, so called "MUSCLE". This paper deals with results and assessment of mask pod environment in term of molecular contamination in a first step, then in a second step preliminary studies to reduce mask pod influence and contamination due to material out gassing. Approach and techniques: A specific assessment of environmental / molecular contamination along the supply chain was performed by all partners. After previous work presented at EMLC 07, further studies were performed on real time contamination measurement pod at different sites locations (including Mask manufacturing site, blank manufacturing sites, IC fab). Studies were linked to the main critical issues: cleaning, storage, handling, materials and processes. Contamination measurement campaigns were carried out along the mask supply chain using specific Adixen analyzer in order to monitor in real time organic contaminants (ppb level) in mask pods. Key results would be presented: VOC, AMC and humidity level on different kinds of mask carriers, impact of basic cleaning on pod outgassing measurement (VOC, NH3), and process influence on pod contamination... In a second step, preliminary specific pod conditioning studies for better pod environment were performed based on Adixen vacuum process. Process influence had been experimentally measured in term of molecular outgassing from mask pods. Different AMC experimental characterization methods had been carried out leading to results on a wide range of organic and inorganic

  3. Acceptability of psychological treatment to Chinese- and Caucasian-Australians: Internet treatment reduces barriers but face-to-face care is preferred.

    PubMed

    Choi, Isabella; Sharpe, Louise; Li, Stephen; Hunt, Caroline

    2015-01-01

    Internet treatments have the potential to improve access, especially for cultural groups who face considerable treatment barriers. This study explored the perceived barriers and likelihood of using Internet and face-to-face treatments for depression among Chinese and Caucasian Australian participants. Three-hundred ninety-five (289 Chinese, 106 Caucasian) primary care patients completed a questionnaire about depression history, previous help-seeking, perceived barriers to Internet and face-to-face treatment, and likelihood of using either treatment for depressive symptoms. Internet treatment reduced perceived barriers (including stigma, lack of motivation, concerns of bringing up upsetting feelings, time constraints, transport difficulties, and cost) for both groups to a similar degree, except for time constraints. There were heightened concerns about the helpfulness, suitability, and confidentiality of Internet treatments. Chinese participants and individuals with a probable depression history reported increased perceived barriers across treatments. Both Chinese and Caucasian groups preferred face-to-face treatment across depression severity. However, when age was controlled, there were no significant concerns about Internet treatment, and face-to-face treatment was only preferred for severe depression. Only 12 % of the entire sample refused to try Internet treatment for depression. Endorsement of perceived Internet treatment barriers (including concerns of bringing up upsetting feelings, that treatment would be unhelpful or unsuitable, lack of motivation, cost, cultural sensitivity, and confidentiality) reduced the likelihood to try Internet treatments. Internet treatment reduced perceived treatment barriers across groups, with encouraging support for Internet treatment as an acceptable form of receiving help. Negative concerns about Internet treatment need to be addressed to encourage use.

  4. X-ray mask fabrication advancements at the Microlithographic Mask Development Center

    NASA Astrophysics Data System (ADS)

    Kimmel, Kurt R.; Hughes, Patrick J.

    1996-05-01

    The Microlithographic Mask Development Center (MMD) was established as the X-ray mask manufacturing facility at the IBM Microelectronics Division semiconductor fabricator in Essex Junction, Vermont. This center, in operation for over two years, produces high yielding, defect-free X-ray masks for competitive logic and memory products at 250nm groundrules and below. The MMD is a complete mask facility that manufactures silicon membrane mask blanks in the NIST format and finished masks with electroplated gold X-ray absorber. Mask patterning, with dimensions as small as 180 nm, is accomplished using IBM-built variable shaped spot e-beam systems. Masks are routinely inspected and repaired using state-of-the-art equipment: two KLA SEM Specs for defect inspection, a Leica LMS 2000 for image placement characterization, an Amray 2040c for image dimension characterization and a Micrion 8000 XMR for defect repair. This facility maintains a baseline mask process with daily production of 250nm, 32Mb SRAM line monitor masks for the continuous improvement of mask quality and processes. Development masks are produced for several semiconductor manufacturers including IBM, Motorola, Loral, and Sanders. Masks for 64Mb and 256Mb DRAM (IBM) and advanced logic/SRAM (IBM and Motorola) designs have also been delivered. This paper describes the MMD facility and its technical capabilities. Key manufacturing metrics such as mask turnaround time, parametric yield learning and defect reduction activities are highlighted. The challenges associated with improved mask quality, sub-180nm mask fabrication, and the transition to refractory metal absorber are discussed.

  5. Phase-shifting point diffraction interferometer mask designs

    DOEpatents

    Goldberg, Kenneth Alan

    2001-01-01

    In a phase-shifting point diffraction interferometer, different image-plane mask designs can improve the operation of the interferometer. By keeping the test beam window of the mask small compared to the separation distance between the beams, the problem of energy from the reference beam leaking through the test beam window is reduced. By rotating the grating and mask 45.degree., only a single one-dimensional translation stage is required for phase-shifting. By keeping two reference pinholes in the same orientation about the test beam window, only a single grating orientation, and thus a single one-dimensional translation stage, is required. The use of a two-dimensional grating allows for a multiplicity of pinholes to be used about the pattern of diffracted orders of the grating at the mask. Orientation marks on the mask can be used to orient the device and indicate the position of the reference pinholes.

  6. Rates of initial acceptance of PAP masks and outcomes of mask switching.

    PubMed

    Bachour, Adel; Vitikainen, Pirjo; Maasilta, Paula

    2016-05-01

    Recently, we noticed a considerable development in alleviating problems related to positive airway pressure (PAP) masks. In this study, we report on the initial PAP mask acceptance rates and the effects of mask switching on mask-related symptoms. We prospectively collected all cases of mask switching in our sleep unit for a period of 14 months. At the time of the study, we used ResMed™ CPAP devices and masks. Mask switching was defined as replacing a mask used for at least 1 day with another type of mask. Changing to a different size but keeping the same type of mask did not count as mask switching. Switching outcomes were considered failed if the initial problem persisted or reappeared during the year that followed switching. Our patient pool was 2768. We recorded 343 cases of mask switching among 267 patients. Of the 566 patients who began new PAP therapy, 108 (39 women) had switched masks, yielding an initial mask acceptance rate of 81 %. The reason for switching was poor-fit/uncomfortable mask in 39 %, leak-related in 30 %, outdated model in 25 %, and nasal stuffiness in 6 % of cases; mask switching resolved these problems in 61 %. Mask switching occurred significantly (p = 0.037) more often in women and in new PAP users. The odds ratio for abandoning PAP therapy within 1 year after mask switching was 7.2 times higher (interval 4.7-11.1) than not switching masks. The initial PAP mask acceptance rate was high. Patients who switched their masks are at greater risk for abandoning PAP therapy.

  7. 42 CFR 84.118 - Half-mask facepieces, full facepieces, and mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Gas Masks § 84.118 Half-mask facepieces, full facepieces, and... reduce the respiratory protective qualities of the gas mask. (c) Half-mask facepieces shall not interfere...

  8. 42 CFR 84.118 - Half-mask facepieces, full facepieces, and mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Gas Masks § 84.118 Half-mask facepieces, full facepieces, and... reduce the respiratory protective qualities of the gas mask. (c) Half-mask facepieces shall not interfere...

  9. 42 CFR 84.118 - Half-mask facepieces, full facepieces, and mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Gas Masks § 84.118 Half-mask facepieces, full facepieces, and... reduce the respiratory protective qualities of the gas mask. (c) Half-mask facepieces shall not interfere...

  10. 42 CFR 84.118 - Half-mask facepieces, full facepieces, and mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Gas Masks § 84.118 Half-mask facepieces, full facepieces, and... reduce the respiratory protective qualities of the gas mask. (c) Half-mask facepieces shall not interfere...

  11. 42 CFR 84.118 - Half-mask facepieces, full facepieces, and mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF RESPIRATORY PROTECTIVE DEVICES Gas Masks § 84.118 Half-mask facepieces, full facepieces, and... reduce the respiratory protective qualities of the gas mask. (c) Half-mask facepieces shall not interfere...

  12. A pattern-based method to automate mask inspection files

    NASA Astrophysics Data System (ADS)

    Kamal Baharin, Ezni Aznida Binti; Muhsain, Mohamad Fahmi Bin; Ahmad Ibrahim, Muhamad Asraf Bin; Ahmad Noorhani, Ahmad Nurul Ihsan Bin; Sweis, Jason; Lai, Ya-Chieh; Hurat, Philippe

    2017-03-01

    Mask inspection is a critical step in the mask manufacturing process in order to ensure all dimensions printed are within the needed tolerances. This becomes even more challenging as the device nodes shrink and the complexity of the tapeout increases. Thus, the amount of measurement points and their critical dimension (CD) types are increasing to ensure the quality of the mask. In addition to the mask quality, there is a significant amount of manpower needed when the preparation and debugging of this process are not automated. By utilizing a novel pattern search technology with the ability to measure and report match region scan-line (edge) measurements, we can create a flow to find, measure and mark all metrology locations of interest and provide this automated report to the mask shop for inspection. A digital library is created based on the technology product and node which contains the test patterns to be measured. This paper will discuss how these digital libraries will be generated and then utilized. As a time-critical part of the manufacturing process, this can also reduce the data preparation cycle time, minimize the amount of manual/human error in naming and measuring the various locations, reduce the risk of wrong/missing CD locations, and reduce the amount of manpower needed overall. We will also review an example pattern and how the reporting structure to the mask shop can be processed. This entire process can now be fully automated.

  13. Face inversion and acquired prosopagnosia reduce the size of the perceptual field of view.

    PubMed

    Van Belle, Goedele; Lefèvre, Philippe; Rossion, Bruno

    2015-03-01

    Using a gaze-contingent morphing approach, we asked human observers to choose one of two faces that best matched the identity of a target face: one face corresponded to the reference face's fixated part only (e.g., one eye), the other corresponded to the unfixated area of the reference face. The face corresponding to the fixated part was selected significantly more frequently in the inverted than in the upright orientation. This observation provides evidence that face inversion reduces an observer's perceptual field of view, even when both upright and inverted faces are displayed at full view and there is no performance difference between these conditions. It rules out an account of the drop of performance for inverted faces--one of the most robust effects in experimental psychology--in terms of a mere difference in local processing efficiency. A brain-damaged patient with pure prosopagnosia, viewing only upright faces, systematically selected the face corresponding to the fixated part, as if her perceptual field was reduced relative to normal observers. Altogether, these observations indicate that the absence of visual knowledge reduces the perceptual field of view, supporting an indirect view of visual perception. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. A Qualitative Impairment in Face Perception in Alzheimer's Disease: Evidence from a Reduced Face Inversion Effect.

    PubMed

    Lavallée, Marie Maxime; Gandini, Delphine; Rouleau, Isabelle; Vallet, Guillaume T; Joannette, Maude; Kergoat, Marie-Jeanne; Busigny, Thomas; Rossion, Bruno; Joubert, Sven

    2016-01-01

    Prevalent face recognition difficulties in Alzheimer's disease (AD) have typically been attributed to the underlying episodic and semantic memory impairment. The aim of the current study was to determine if AD patients are also impaired at the perceptual level for faces, more specifically at extracting a visual representation of an individual face. To address this question, we investigated the matching of simultaneously presented individual faces and of other nonface familiar shapes (cars), at both upright and inverted orientation, in a group of mild AD patients and in a group of healthy older controls matched for age and education. AD patients showed a reduced inversion effect (i.e., larger performance for upright than inverted stimuli) for faces, but not for cars, both in terms of error rates and response times. While healthy participants showed a much larger decrease in performance for faces than for cars with inversion, the inversion effect did not differ significantly for faces and cars in AD. This abnormal inversion effect for faces was observed in a large subset of individual patients with AD. These results suggest that AD patients have deficits in higher-level visual processes, more specifically at perceiving individual faces, a function that relies on holistic representations specific to upright face stimuli. These deficits, combined with their memory impairment, may contribute to the difficulties in recognizing familiar people that are often reported in patients suffering from the disease and by their caregivers.

  15. Development of Personalized Fitting Device With 3-Dimensional Solution for Prevention of NIV Oronasal Mask-Related Pressure Ulcers.

    PubMed

    Shikama, Maiko; Nakagami, Gojiro; Noguchi, Hiroshi; Mori, Taketoshi; Sanada, Hiromi

    2018-05-22

    Pressure ulcers related to oronasal masks used with noninvasive ventilation (NIV), along with patient discomfort, occur due to improper fit of the mask. We developed a personalized fitting device using a 3-dimensional (3D) scanning solution to prevent the formation of NIV mask-related pressure ulcers. This study aimed to evaluate the effectiveness of the proposed personalized fitting device. We conducted a randomized crossover experimental study of 20 healthy participants to study the use of this personalized fitting device between the face and an NIV mask designed with 3D solutions. The fitting device was not used under the NIV mask for the control. The outcome measures were the presence of blanchable erythema, standardized redness intensity, discomfort level, and contact pressure. The incidence of blanchable erythema and standardized redness intensity values were significantly lower for subjects who used the fitting device when worn for 30 min ( P < .001). The discomfort levels at the forehead, nasal bridge, and both cheeks, as well as leakage, were significantly reduced as well ( P = .008, P < .001, P = .001, P = .002, P = .001, P = .02, P < .001, P < .001, P < .001). Contact pressure at the nasal bridge, where pressure ulcers most frequently develop, was significantly decreased with the fitting device ( P < .001). Personalized fitting devices that incorporate 3D scanning solutions may contribute to the prevention of NIV mask-related pressure ulcers and the reduction of discomfort. Copyright © 2018 by Daedalus Enterprises.

  16. Fast mask writers: technology options and considerations

    NASA Astrophysics Data System (ADS)

    Litt, Lloyd C.; Groves, Timothy; Hughes, Greg

    2011-04-01

    The semiconductor industry is under constant pressure to reduce production costs even as the complexity of technology increases. Lithography represents the most expensive process due to its high capital equipment costs and the implementation of low-k1 lithographic processes, which have added to the complexity of making masks because of the greater use of optical proximity correction, pixelated masks, and double or triple patterning. Each of these mask technologies allows the production of semiconductors at future nodes while extending the utility of current immersion tools. Low-k1 patterning complexity combined with increased data due to smaller feature sizes is driving extremely long mask write times. While a majority of the industry is willing to accept times of up to 24 hours, evidence suggests that the write times for many masks at the 22 nm node and beyond will be significantly longer. It has been estimated that funding on the order of 50M to 90M for non-recurring engineering (NRE) costs will be required to develop a multiple beam mask writer system, yet the business case to recover this kind of investment is not strong. Moreover, funding such a development poses a high risk for an individual supplier. The structure of the mask fabrication marketplace separates the mask writer equipment customer (the mask supplier) from the final customer (wafer manufacturer) that will be most effected by the increase in mask cost that will result if a high speed mask writer is not available. Since no individual company will likely risk entering this market, some type of industry-wide funding model will be needed.

  17. Filter penetration and breathing resistance evaluation of respirators and dust masks.

    PubMed

    Ramirez, Joel; O'Shaughnessy, Patrick

    2017-02-01

    The primary objective of this study was to compare the filter performance of a representative selection of uncertified dust masks relative to the filter performance of a set of NIOSH-approved N95 filtering face-piece respirators (FFRs). Five different models of commercially available dust masks were selected for this study. Filter penetration of new dust masks was evaluated against a sodium chloride aerosol. Breathing resistance (BR) of new dust masks and FFRs was then measured for 120 min while challenging the dust masks and FFRs with Arizona road dust (ARD) at 25°C and 30% relative humidity. Results demonstrated that a wide range of maximum filter penetration was observed among the dust masks tested in this study (3-75% at the most penetrating particle size (p < 0.001). The breathing resistances of the unused FFRs and dust masks did not vary greatly (8-13 mm H 2 O) but were significantly different (p < 0.001). After dust loading there was a significant difference between the BR caused by the ARD dust layer on each FFR and dust mask. Microscopic analysis of the external layer of each dust mask and FFR suggests that different collection media in the external layer influences the development of the dust layer and therefore affects the increase in BR differently between the tested models. Two of the dust masks had penetration values < 5% and quality factors (0.26 and 0.33) comparable to those obtained for the two FFRs (0.23 and 0.31). However, the remaining three dust masks, those with penetration > 15%, had quality factors ranging between 0.04-0.15 primarily because their initial BR remained relatively high. These results indicate that some dust masks analysed during this research did not have an expected very low BR to compensate for their high penetration.

  18. Autistic traits are linked to reduced adaptive coding of face identity and selectively poorer face recognition in men but not women.

    PubMed

    Rhodes, Gillian; Jeffery, Linda; Taylor, Libby; Ewing, Louise

    2013-11-01

    Our ability to discriminate and recognize thousands of faces despite their similarity as visual patterns relies on adaptive, norm-based, coding mechanisms that are continuously updated by experience. Reduced adaptive coding of face identity has been proposed as a neurocognitive endophenotype for autism, because it is found in autism and in relatives of individuals with autism. Autistic traits can also extend continuously into the general population, raising the possibility that reduced adaptive coding of face identity may be more generally associated with autistic traits. In the present study, we investigated whether adaptive coding of face identity decreases as autistic traits increase in an undergraduate population. Adaptive coding was measured using face identity aftereffects, and autistic traits were measured using the Autism-Spectrum Quotient (AQ) and its subscales. We also measured face and car recognition ability to determine whether autistic traits are selectively related to face recognition difficulties. We found that men who scored higher on levels of autistic traits related to social interaction had reduced adaptive coding of face identity. This result is consistent with the idea that atypical adaptive face-coding mechanisms are an endophenotype for autism. Autistic traits were also linked with face-selective recognition difficulties in men. However, there were some unexpected sex differences. In women, autistic traits were linked positively, rather than negatively, with adaptive coding of identity, and were unrelated to face-selective recognition difficulties. These sex differences indicate that autistic traits can have different neurocognitive correlates in men and women and raise the intriguing possibility that endophenotypes of autism can differ in males and females. © 2013 Elsevier Ltd. All rights reserved.

  19. Categorical scaling of partial loudness in a condition of masking release.

    PubMed

    Verhey, Jesko L; Heeren, Wiebke

    2015-08-01

    Categorical loudness scaling was used to measure suprathreshold release from masking. The signal was a 986-Hz sinusoid that was embedded in a bandpass-filtered masking noise. This noise was either unmodulated or was amplitude modulated with a square-wave modulator. The unmodulated noise had either the same level as the modulated noise or had a level that was reduced by the difference in thresholds for the 986-Hz signal obtained with the modulated and unmodulated noise masker presented at the same level (i.e., the masking release). A comparison with loudness matching data of the same set of subjects showed that the data obtained with loudness scaling capture main aspects of the change in suprathreshold perception of the sinusoid when the masker was modulated. The scaling data for the signal masked by the unmodulated noise with the reduced masker level were similar to that for the signal embedded in the modulated noise. This similarity supports the hypothesis that the mechanism eliciting the masking release is effectively reducing the masker level.

  20. Aerial image metrology for OPC modeling and mask qualification

    NASA Astrophysics Data System (ADS)

    Chen, Ao; Foong, Yee Mei; Thaler, Thomas; Buttgereit, Ute; Chung, Angeline; Burbine, Andrew; Sturtevant, John; Clifford, Chris; Adam, Kostas; De Bisschop, Peter

    2017-06-01

    As nodes become smaller and smaller, the OPC applied to enable these nodes becomes more and more sophisticated. This trend peaks today in curve-linear OPC approaches that are currently starting to appear on the roadmap. With this sophistication of OPC, the mask pattern complexity increases. CD-SEM based mask qualification strategies as they are used today are starting to struggle to provide a precise forecast of the printing behavior of a mask on wafer. An aerial image CD measurement performed on ZEISS Wafer-Level CD system (WLCD) is a complementary approach to mask CD-SEMs to judge the lithographical performance of the mask and its critical production features. The advantage of the aerial image is that it includes all optical effects of the mask such as OPC, SRAF, 3D mask effects, once the image is taken under scanner equivalent illumination conditions. Additionally, it reduces the feature complexity and analyzes the printing relevant CD.

  1. EUVL masks: paving the path for commercialization

    NASA Astrophysics Data System (ADS)

    Mangat, Pawitter J. S.; Hector, Scott D.

    2001-09-01

    Optical projection lithography has been the principal vehicle of semiconductor manufacturing for more than 20 years and is marching aggressively to satisfy the needs of semiconductor manufacturers for 100nm devices. However, the complexity of optical lithography continues to increase as wavelength reduction continues to 157nm. Extreme Ultraviolet Lithography (EUVL), with wavelength from 13-14 nm, is evolving as a leading next generation lithography option for semiconductor industry to stay on the path laid by Moore's Law. Masks are a critical part of the success of any technology and are considered to be high risk both for optical lithography and NGL technologies for sub-100nm lithography. Two key areas of EUV mask fabrication are reflective multilayer deposition and absorber patterning. In the case of reflective multilayers, delivering defect free multilayers for mask blanks is the biggest challenge. Defect mitigation is being explored as a possible option to smooth the multilayer defects in addition to optimization of the deposition process to reduce defect density. The mask patterning process needs focus on the defect-free absorber stack patterning process, mask cleaning, inspection and repair. In addition, there is considerable effort to understand by simulations, the defect printability, thermal and mechanical distortions, and non-telecentric illumination, to mention a few. To protect the finished mask from defects added during use, a removable pellicle strategy combined with thermophoretic protection during exposure is being developed. Recent migration to square form factor using low thermal expansion material (LTEM) is advantageous as historical developments in optical masks can be applied to EUV mask patterning. This paper addresses recent developments in the EUV mask patterning and highlights critical manufacturing process controls needed to fabricate defect-free full field masks with CD and image placement specifications for sub-70nm node lithography. No

  2. Bitter taste masking of enzyme-treated soy protein in water and bread.

    PubMed

    Bertelsen, Anne S; Laursen, Anne; Knudsen, Tine A; Møller, Stine; Kidmose, Ulla

    2018-08-01

    Bioactive protein hydrolysates are often very bitter. To overcome this challenge, xylitol, sucrose, α-cyclodextrin, maltodextrin and combinations of these were tested systematically as bitter-masking agents of an enzyme-treated soy protein in an aqueous model and in a bread model. Sensory descriptive analysis was used to reveal the bitter-masking effect of the taste-masking blends on the enzyme-treated soy protein. In water, xylitol, sucrose and maltodextrin reduced bitterness significantly, whereas α-cyclodextrin did not. No significant difference was observed in bitterness reduction between xylitol and sucrose. Both reduced bitterness significantly more than maltodextrin. No interactions between the taste-masking agents affecting bitterness reduction were found. Clearer bitter-masking effects were seen in the aqueous model compared with the bread model. The bitter-masking effects of α-cyclodextrin and maltodextrin were similar between water and bread. The effect of xylitol and sucrose on bitterness suppression varied between the systems. In water, bitterness was negatively correlated with sweetness. In bread, bitterness was negatively correlated with freshness, and maltodextrin significantly reduced bitterness of the enzyme-treated soy protein and increased freshness. Bitter-masking effects were generally more discernible in the aqueous model compared with the bread model. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  3. Spatial Attention-Related Modulation of the N170 by Backward Masked Fearful Faces

    ERIC Educational Resources Information Center

    Carlson, Joshua M.; Reinke, Karen S.

    2010-01-01

    Facial expressions are a basic form of non-verbal communication that convey important social information to others. The relevancy of this information is highlighted by findings that backward masked facial expressions facilitate spatial attention. This attention effect appears to be mediated through a neural network consisting of the amygdala,…

  4. Electroconvulsive therapy can benefit from controlled hyperventilation using a laryngeal mask.

    PubMed

    Haeck, Martina; Gillmann, Benjamin; Janouschek, Hildegard; Grözinger, Michael

    2011-11-01

    Hypocapnia through hyperventilation is a well-known procedure in electroconvulsive therapy (ECT) to enhance seizure activity. However, it has mostly been applied in an uncontrolled manner. Originally intended for a better management of the supraglottic airway, laryngeal masks are more suited to monitor levels of CO(2) during hyperventilation than face masks and thereby provide for the possibility of controlled hyperventilation (CHV). The impact of CHV was retrospectively studied in 114 consecutive patients; 65 of them had received ECT with CHV and 49 had received ECT with uncontrolled hyperventilation (UHV) directly prior to the time period when the laryneal mask was introduced to the ECT treatment procedure. The CO(2) level in the CHV group was aimed at 30 mmHg or below. CHV considerably enhanced the seizure activity leading to changes in clinically determined parameters of the treatment course: the necessity for increasing the electric charge, for re-stimulations (trend) and for bilateral stimulations was lower in the CHV group as compared to the UHV group. The improvement in the Global Assessment of Functioning Scores was not different in both groups. CHV was associated with a higher amount of prolonged seizures, with a reduced number of delirious symptoms after treatments and an attenuating effect on heart rate. Concluding, CHV can help to maintain the applied electric charge low without worsening the clinical outcome. Therefore, it is a helpful technical improvement. However, it should be used carefully with regard to prolonged seizures.

  5. [Laryngeal mask].

    PubMed

    Villaverde Rozados, María José; Mos Reguera, M Esther; González Argibay, M Concepción; Sixto Gato, Sandra; Radío, Beatriz Alfonso; Fernández Díaz, María José

    2003-11-01

    A laryngeal mask is a very useful instrument to use both in easy as well as difficult handling situations related to the air tract. This mask is placed in the pharynx and it permits a patient to breathe in different modes, either spontaneously or mechanically. Different models are available; some even facilitate the tracheal intubation through the mask. The authors highlight that this type of mask does not protect nor isolate the air tract. As advantages, the authors point out its easy installation; thus, it is an alternative when an air tract presents difficulties; therefore, it is necessary that all personnel who have to deal with the air tract be aware of this mask and know how to handle it.

  6. Advances in low-defect multilayers for EUVL mask blanks

    NASA Astrophysics Data System (ADS)

    Folta, James A.; Davidson, J. Courtney; Larson, Cindy C.; Walton, Christopher C.; Kearney, Patrick A.

    2002-07-01

    Low-defect multilayer coatings are required to fabricate mask blanks for Extreme Ultraviolet Lithography (EUVL). The mask blanks consist of high reflectance EUV multilayers on low thermal expansion substrates. A defect density of 0.0025 printable defects/cm2 for both the mask substrate and the multilayer is required to provide a mask blank yield of 60 percent. Current low defect multilayer coating technology allows repeated coating-added defect levels of 0.05/cm2 for defects greater than 90 nm polystyrene latex sphere (PSL) equivalent size for lots of 20 substrates. Extended clean operation of the coating system at levels below 0.08/cm2 for 3 months of operation has also been achieved. Two substrates with zero added defects in the quality area have been fabricated, providing an existence proof that ultra low defect coatings are possible. Increasing the ion source-to-target distance from 410 to 560 mm to reduce undesired coating of the ion source caused the defect density to increase to 0.2/cm2. Deposition and etching diagnostic witness substrates and deposition pinhole cameras showed a much higher level of ion beam spillover (ions missing the sputter target) than expected. Future work will quantify beam spillover, and test designs to reduce spillover, if it is confirmed to be the cause of the increased defect level. The LDD system will also be upgraded to allow clean coating of standard format mask substrates. The upgrade will confirm that the low defect process developed on Si wafers is compatible with the standard mask format 152 mm square substrates, and will provide a clean supply of EUVL mask blanks needed to support development of EUVL mask patterning processes and clean mask handling technologies.

  7. Modeling of thermomechanical changes of extreme-ultraviolet mask and their dependence on absorber variation

    NASA Astrophysics Data System (ADS)

    Ban, Chung-Hyun; Park, Eun-Sang; Park, Jae-Hun; Oh, Hye-Keun

    2018-06-01

    Thermal and structural deformation of extreme-ultraviolet lithography (EUVL) masks during the exposure process may become important issues as these masks are subject to rigorous image placement and flatness requirements. The reflective masks used for EUVL absorb energy during exposure, and the temperature of the masks rises as a result. This can cause thermomechanical deformation that can reduce the pattern quality. The use of very thick low-thermal-expansion substrate materials (LTEMs) may reduce energy absorption, but they do not completely eliminate mask deformation. Therefore, it is necessary to predict and optimize the effects of energy transferred from the extreme-ultraviolet (EUV) light source and the resultant patterns of structured EUV masks with complex multilayers. Our study shows that heat accumulates in the masks as exposure progresses. It has been found that a higher absorber ratio (pattern density) applied to the patterning of EUV masks exacerbates the problem, especially in masks with more complex patterns.

  8. Seeing a haptically explored face: visual facial-expression aftereffect from haptic adaptation to a face.

    PubMed

    Matsumiya, Kazumichi

    2013-10-01

    Current views on face perception assume that the visual system receives only visual facial signals. However, I show that the visual perception of faces is systematically biased by adaptation to a haptically explored face. Recently, face aftereffects (FAEs; the altered perception of faces after adaptation to a face) have been demonstrated not only in visual perception but also in haptic perception; therefore, I combined the two FAEs to examine whether the visual system receives face-related signals from the haptic modality. I found that adaptation to a haptically explored facial expression on a face mask produced a visual FAE for facial expression. This cross-modal FAE was not due to explicitly imaging a face, response bias, or adaptation to local features. Furthermore, FAEs transferred from vision to haptics. These results indicate that visual face processing depends on substrates adapted by haptic faces, which suggests that face processing relies on shared representation underlying cross-modal interactions.

  9. Influence of auditory fatigue on masked speech intelligibility

    NASA Technical Reports Server (NTRS)

    Parker, D. E.; Martens, W. L.; Johnston, P. A.

    1980-01-01

    Intelligibility of PB word lists embedded in simultaneous masking noise was evaluated before and after fatiguing-noise exposure, which was determined by observing the number of words correctly repeated during a shadowing task. Both the speech signal and the masking noise were filtered to a 2825-3185-Hz band. Masking-noise leves were varied from 0- to 90-dB SL. Fatigue was produced by a 1500-3000-Hz octave band of noise at 115 dB (re 20 micron-Pa) presented continuously for 5 min. The results of three experiments indicated that speed intelligibility was reduced when the speech was presented against a background of silence but that the fatiguing-noise exposure had no effect on intelligibility when the speech was made more intense and embedded in masking noise of 40-90-dB SL. These observations are interpreted by considering the recruitment produced by fatigue and masking noise.

  10. Reduced beta connectivity during emotional face processing in adolescents with autism.

    PubMed

    Leung, Rachel C; Ye, Annette X; Wong, Simeon M; Taylor, Margot J; Doesburg, Sam M

    2014-01-01

    Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairments in social cognition. The biological basis of deficits in social cognition in ASD, and their difficulty in processing emotional face information in particular, remains unclear. Atypical communication within and between brain regions has been reported in ASD. Interregional phase-locking is a neurophysiological mechanism mediating communication among brain areas and is understood to support cognitive functions. In the present study we investigated interregional magnetoencephalographic phase synchronization during the perception of emotional faces in adolescents with ASD. A total of 22 adolescents with ASD (18 males, mean age =14.2 ± 1.15 years, 22 right-handed) with mild to no cognitive delay and 17 healthy controls (14 males, mean age =14.4 ± 0.33 years, 16 right-handed) performed an implicit emotional processing task requiring perception of happy, angry and neutral faces while we recorded neuromagnetic signals. The faces were presented rapidly (80 ms duration) to the left or right of a central fixation cross and participants responded to a scrambled pattern that was presented concurrently on the opposite side of the fixation point. Task-dependent interregional phase-locking was calculated among source-resolved brain regions. Task-dependent increases in interregional beta synchronization were observed. Beta-band interregional phase-locking in adolescents with ASD was reduced, relative to controls, during the perception of angry faces in a distributed network involving the right fusiform gyrus and insula. No significant group differences were found for happy or neutral faces, or other analyzed frequency ranges. Significant reductions in task-dependent beta connectivity strength, clustering and eigenvector centrality (all P <0.001) in the right insula were found in adolescents with ASD, relative to controls. Reduced beta synchronization may reflect inadequate

  11. Spontaneous Gender Categorization in Masking and Priming Studies: Key for Distinguishing Jane from John Doe but Not Madonna from Sinatra

    PubMed Central

    Habibi, Ruth; Khurana, Beena

    2012-01-01

    Facial recognition is key to social interaction, however with unfamiliar faces only generic information, in the form of facial stereotypes such as gender and age is available. Therefore is generic information more prominent in unfamiliar versus familiar face processing? In order to address the question we tapped into two relatively disparate stages of face processing. At the early stages of encoding, we employed perceptual masking to reveal that only perception of unfamiliar face targets is affected by the gender of the facial masks. At the semantic end; using a priming paradigm, we found that while to-be-ignored unfamiliar faces prime lexical decisions to gender congruent stereotypic words, familiar faces do not. Our findings indicate that gender is a more salient dimension in unfamiliar relative to familiar face processing, both in early perceptual stages as well as later semantic stages of person construal. PMID:22389697

  12. Masking interrupts figure-ground signals in V1.

    PubMed

    Lamme, Victor A F; Zipser, Karl; Spekreijse, Henk

    2002-10-01

    In a backward masking paradigm, a target stimulus is rapidly (<100 msec) followed by a second stimulus. This typically results in a dramatic decrease in the visibility of the target stimulus. It has been shown that masking reduces responses in V1. It is not known, however, which process in V1 is affected by the mask. In the past, we have shown that in V1, modulations of neural activity that are specifically related to figure-ground segregation can be recorded. Here, we recorded from awake macaque monkeys, engaged in a task where they had to detect figures from background in a pattern backward masking paradigm. We show that the V1 figure-ground signals are selectively and fully suppressed at target-mask intervals that psychophysically result in the target being invisible. Initial response transients, signalling the features that make up the scene, are not affected. As figure-ground modulations depend on feedback from extrastriate areas, these results suggest that masking selectively interrupts the recurrent interactions between V1 and higher visual areas.

  13. Asymmetry in Object Substitution Masking Occurs Relative to the Direction of Spatial Attention Shift

    ERIC Educational Resources Information Center

    Hirose, Nobuyuki; Osaka, Naoyuki

    2010-01-01

    A sparse mask that persists beyond the duration of a target can reduce its visibility, a phenomenon called "object substitution masking". Y. Jiang and M. M. Chun (2001a) found an asymmetric pattern of substitution masking such that a mask on the peripheral side of the target caused stronger substitution masking than on the central side.…

  14. A procedure and program to calculate shuttle mask advantage

    NASA Astrophysics Data System (ADS)

    Balasinski, A.; Cetin, J.; Kahng, A.; Xu, X.

    2006-10-01

    A well-known recipe for reducing mask cost component in product development is to place non-redundant elements of layout databases related to multiple products on one reticle plate [1,2]. Such reticles are known as multi-product, multi-layer, or, in general, multi-IP masks. The composition of the mask set should minimize not only the layout placement cost, but also the cost of the manufacturing process, design flow setup, and product design and introduction to market. An important factor is the quality check which should be expeditious and enable thorough visual verification to avoid costly modifications once the data is transferred to the mask shop. In this work, in order to enable the layer placement and quality check procedure, we proposed an algorithm where mask layers are first lined up according to the price and field tone [3]. Then, depending on the product die size, expected fab throughput, and scribeline requirements, the subsequent product layers are placed on the masks with different grades. The actual reduction of this concept to practice allowed us to understand the tradeoffs between the automation of layer placement and setup related constraints. For example, the limited options of the numbers of layer per plate dictated by the die size and other design feedback, made us consider layer pairing based not only on the final price of the mask set, but also on the cost of mask design and fab-friendliness. We showed that it may be advantageous to introduce manual layer pairing to ensure that, e.g., all interconnect layers would be placed on the same plate, allowing for easy and simultaneous design fixes. Another enhancement was to allow some flexibility in mixing and matching of the layers such that non-critical ones requiring low mask grade would be placed in a less restrictive way, to reduce the count of orphan layers. In summary, we created a program to automatically propose and visualize shuttle mask architecture for design verification, with

  15. "The Mask Who Wasn't There": Visual Masking Effect with the Perceptual Absence of the Mask

    ERIC Educational Resources Information Center

    Rey, Amandine Eve; Riou, Benoit; Muller, Dominique; Dabic, Stéphanie; Versace, Rémy

    2015-01-01

    Does a visual mask need to be perceptually present to disrupt processing? In the present research, we proposed to explore the link between perceptual and memory mechanisms by demonstrating that a typical sensory phenomenon (visual masking) can be replicated at a memory level. Experiment 1 highlighted an interference effect of a visual mask on the…

  16. Profiles of Patients Demonstrating Abnormal Masking Level Difference Response.

    ERIC Educational Resources Information Center

    Battin, R. Ray; Waryas, Paul A.

    1985-01-01

    Profiles of three persons (9-11 years old) with extremely reduced masking level difference results (scores which measure binaural release from masking) are reported. It is suggested that tests of the MLD appear to be a useful adjunct of an evaluation battery for patients with presumed auditory perceptual problems. (CL)

  17. Motion artifact and background noise suppression on optical microangiography frames using a naïve Bayes mask.

    PubMed

    Reif, Roberto; Baran, Utku; Wang, Ruikang K

    2014-07-01

    Optical coherence tomography (OCT) is a technique that allows for the three-dimensional (3D) imaging of small volumes of tissue (a few millimeters) with high resolution (∼10  μm). Optical microangiography (OMAG) is a method of processing OCT data, which allows for the extraction of the tissue vasculature with capillary resolution from the OCT images. Cross-sectional B-frame OMAG images present the location of the patent blood vessels; however, the signal-to-noise-ratio of these images can be affected by several factors such as the quality of the OCT system and the tissue motion artifact. This background noise can appear in the en face projection view image. In this work we propose to develop a binary mask that can be applied on the cross-sectional B-frame OMAG images, which will reduce the background noise while leaving the signal from the blood vessels intact. The mask is created by using a naïve Bayes (NB) classification algorithm trained with a gold standard image which is manually segmented by an expert. The masked OMAG images present better contrast for binarizing the image and quantifying the result without the influence of noise. The results are compared with a previously developed frequency rejection filter (FRF) method which is applied on the en face projection view image. It is demonstrated that both the NB and FRF methods provide similar vessel length fractions. The advantage of the NB method is that the results are applicable in 3D and that its use is not limited to periodic motion artifacts.

  18. Secondary gamma-ray production in a coded aperture mask

    NASA Technical Reports Server (NTRS)

    Owens, A.; Frye, G. M., Jr.; Hall, C. J.; Jenkins, T. L.; Pendleton, G. N.; Carter, J. N.; Ramsden, D.; Agrinier, B.; Bonfand, E.; Gouiffes, C.

    1985-01-01

    The application of the coded aperture mask to high energy gamma-ray astronomy will provide the capability of locating a cosmic gamma-ray point source with a precision of a few arc-minutes above 20 MeV. Recent tests using a mask in conjunction with drift chamber detectors have shown that the expected point spread function is achieved over an acceptance cone of 25 deg. A telescope employing this technique differs from a conventional telescope only in that the presence of the mask modifies the radiation field in the vicinity of the detection plane. In addition to reducing the primary photon flux incident on the detector by absorption in the mask elements, the mask will also be a secondary radiator of gamma-rays. The various background components in a CAMTRAC (Coded Aperture Mask Track Chamber) telescope are considered. Monte-Carlo calculations are compared with recent measurements obtained using a prototype instrument in a tagged photon beam line.

  19. The amygdala is involved in affective priming effect for fearful faces.

    PubMed

    Yang, J; Cao, Z; Xu, X; Chen, G

    2012-10-01

    The object of this study was to investigate whether the amygdala is involved in affective priming effect after stimuli are encoded unconsciously and consciously. During the encoding phase, each masked face (fearful or neutral) was presented to participants six times for 17ms each, using a backward masking paradigm. During the retrieval phase, participants made a fearful/neutral judgment for each face. Half of the faces had the same valence as that seen during encoding (congruent condition) and the other half did not (incongruent condition). Participants were divided into unaware and aware groups based on their subjective and objective awareness assessments. The fMRI results showed that during encoding, the amygdala elicited stronger activation for fearful faces than neutral faces but differed in the hemisphere according to the awareness level. During retrieval, the amygdala showed a significant repetition priming effect, with the congruent faces producing less activation than the incongruent faces, especially for fearful faces. These data suggest that the amygdala is important in unconscious retrieving of memories for emotional faces whether they are encoded consciously or unconsciously. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Current status of x-ray mask manufacturing at the Microlithographic Mask Development Center

    NASA Astrophysics Data System (ADS)

    Kimmel, Kurt R.; Hughes, Patrick J.

    1996-07-01

    The Microlithographic Mask Development Center (MMD) has been the focal point of X-ray mask development efforts in the United States since its inception in 1993. Funded by the Advanced Research Projects Agency (ARPA), and with technical support from the Proximity X-ray Lithography Association (AT&T, IBM, Loral Federal Systems, and Motorola) the MMD has recently made dramatic advances in mask fabrication. Numerous defect-free 64Mb and 256Mb DRAM masks have been made on both boron-doped silicon and silicon carbide substrates. Image-placement error of less than 35nm 3 sigma is achieved with high yield. Image-size (critical dimension) control of 25nm 3 sigma on 250nm nominal images is representative performance. This progress is being made in a manufacturing environment with significant volumes, multiple customers, multiple substrate configurations, and fast turnaround-time (TAT) requirements. The MMD state-of-the-art equipment infrastructure has made much of this progress possible. This year the MMD qualified the EL-4, an IBM-designed-and-built variable-shaped-spot e-beam system. The fundamental performance parameters of this system will be described. Operational techniques of multiple partial exposure writing and product specific emulation (PSE) have been implemented to improve image-placement accuracy with remarkable success. Image-size control was studied in detail with contributory components separated. Defect density was systematically reduced to yield defect-free masks while simultaneously tightening inspection criteria. Information about these and other recent engineering highlights will be reported. An outline of the primary engineering challenges and goals for 1996 and status of progress toward 100 nm design rule capability will also be given.

  1. Mask automation: need a revolution in mask makers and equipment industry

    NASA Astrophysics Data System (ADS)

    Moon, Seong-yong; Yu, Sang-yong; Noh, Young-hwa; Son, Ki-jung; Lee, Hyun-Joo; Cho, Han-Ku

    2013-09-01

    As improving device integration for the next generation, high performance and cost down are also required accordingly in semiconductor business. Recently, significant efforts have been given on putting EUV technology into fabrication in order to improve device integration. At the same time, 450mm wafer manufacturing environment has been considered seriously in many ways in order to boost up the productivity. Accordingly, 9-inch mask has been discussed in mask fabrication business recently to support 450mm wafer manufacturing environment successfully. Although introducing 9-inch mask can be crucial for mask industry, multi-beam technology is also expected as another influential turning point to overcome currently the most critical issue in mask industry, electron beam writing time. No matter whether 9-inch mask or multi-beam technology will be employed or not, mask quality and productivity will be the key factors to survive from the device competition. In this paper, the level of facility automation in mask industry is diagnosed and analyzed and the automation guideline is suggested for the next generation.

  2. Emotional facial expressions reduce neural adaptation to face identity.

    PubMed

    Gerlicher, Anna M V; van Loon, Anouk M; Scholte, H Steven; Lamme, Victor A F; van der Leij, Andries R

    2014-05-01

    In human social interactions, facial emotional expressions are a crucial source of information. Repeatedly presented information typically leads to an adaptation of neural responses. However, processing seems sustained with emotional facial expressions. Therefore, we tested whether sustained processing of emotional expressions, especially threat-related expressions, would attenuate neural adaptation. Neutral and emotional expressions (happy, mixed and fearful) of same and different identity were presented at 3 Hz. We used electroencephalography to record the evoked steady-state visual potentials (ssVEP) and tested to what extent the ssVEP amplitude adapts to the same when compared with different face identities. We found adaptation to the identity of a neutral face. However, for emotional faces, adaptation was reduced, decreasing linearly with negative valence, with the least adaptation to fearful expressions. This short and straightforward method may prove to be a valuable new tool in the study of emotional processing.

  3. Automatic pattern localization across layout database and photolithography mask

    NASA Astrophysics Data System (ADS)

    Morey, Philippe; Brault, Frederic; Beisser, Eric; Ache, Oliver; Röth, Klaus-Dieter

    2016-03-01

    Advanced process photolithography masks require more and more controls for registration versus design and critical dimension uniformity (CDU). The distribution of the measurement points should be distributed all over the whole mask and may be denser in areas critical to wafer overlay requirements. This means that some, if not many, of theses controls should be made inside the customer die and may use non-dedicated patterns. It is then mandatory to access the original layout database to select patterns for the metrology process. Finding hundreds of relevant patterns in a database containing billions of polygons may be possible, but in addition, it is mandatory to create the complete metrology job fast and reliable. Combining, on one hand, a software expertise in mask databases processing and, on the other hand, advanced skills in control and registration equipment, we have developed a Mask Dataprep Station able to select an appropriate number of measurement targets and their positions in a huge database and automatically create measurement jobs on the corresponding area on the mask for the registration metrology system. In addition, the required design clips are generated from the database in order to perform the rendering procedure on the metrology system. This new methodology has been validated on real production line for the most advanced process. This paper presents the main challenges that we have faced, as well as some results on the global performances.

  4. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers.

    PubMed

    MacIntyre, C Raina; Seale, Holly; Dung, Tham Chi; Hien, Nguyen Tran; Nga, Phan Thi; Chughtai, Abrar Ahmad; Rahman, Bayzidur; Dwyer, Dominic E; Wang, Quanyi

    2015-04-22

    The aim of this study was to compare the efficacy of cloth masks to medical masks in hospital healthcare workers (HCWs). The null hypothesis is that there is no difference between medical masks and cloth masks. 14 secondary-level/tertiary-level hospitals in Hanoi, Vietnam. 1607 hospital HCWs aged ≥18 years working full-time in selected high-risk wards. Hospital wards were randomised to: medical masks, cloth masks or a control group (usual practice, which included mask wearing). Participants used the mask on every shift for 4 consecutive weeks. Clinical respiratory illness (CRI), influenza-like illness (ILI) and laboratory-confirmed respiratory virus infection. The rates of all infection outcomes were highest in the cloth mask arm, with the rate of ILI statistically significantly higher in the cloth mask arm (relative risk (RR)=13.00, 95% CI 1.69 to 100.07) compared with the medical mask arm. Cloth masks also had significantly higher rates of ILI compared with the control arm. An analysis by mask use showed ILI (RR=6.64, 95% CI 1.45 to 28.65) and laboratory-confirmed virus (RR=1.72, 95% CI 1.01 to 2.94) were significantly higher in the cloth masks group compared with the medical masks group. Penetration of cloth masks by particles was almost 97% and medical masks 44%. This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. This is an important finding to inform occupational health and safety. Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection. Further research is needed to inform the widespread use of cloth masks globally. However, as a precautionary measure, cloth masks should not be recommended for HCWs, particularly in high-risk situations, and guidelines need to be updated. Australian New Zealand Clinical Trials Registry: ACTRN12610000887077. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go

  5. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers

    PubMed Central

    MacIntyre, C Raina; Seale, Holly; Dung, Tham Chi; Hien, Nguyen Tran; Nga, Phan Thi; Chughtai, Abrar Ahmad; Rahman, Bayzidur; Dwyer, Dominic E; Wang, Quanyi

    2015-01-01

    Objective The aim of this study was to compare the efficacy of cloth masks to medical masks in hospital healthcare workers (HCWs). The null hypothesis is that there is no difference between medical masks and cloth masks. Setting 14 secondary-level/tertiary-level hospitals in Hanoi, Vietnam. Participants 1607 hospital HCWs aged ≥18 years working full-time in selected high-risk wards. Intervention Hospital wards were randomised to: medical masks, cloth masks or a control group (usual practice, which included mask wearing). Participants used the mask on every shift for 4 consecutive weeks. Main outcome measure Clinical respiratory illness (CRI), influenza-like illness (ILI) and laboratory-confirmed respiratory virus infection. Results The rates of all infection outcomes were highest in the cloth mask arm, with the rate of ILI statistically significantly higher in the cloth mask arm (relative risk (RR)=13.00, 95% CI 1.69 to 100.07) compared with the medical mask arm. Cloth masks also had significantly higher rates of ILI compared with the control arm. An analysis by mask use showed ILI (RR=6.64, 95% CI 1.45 to 28.65) and laboratory-confirmed virus (RR=1.72, 95% CI 1.01 to 2.94) were significantly higher in the cloth masks group compared with the medical masks group. Penetration of cloth masks by particles was almost 97% and medical masks 44%. Conclusions This study is the first RCT of cloth masks, and the results caution against the use of cloth masks. This is an important finding to inform occupational health and safety. Moisture retention, reuse of cloth masks and poor filtration may result in increased risk of infection. Further research is needed to inform the widespread use of cloth masks globally. However, as a precautionary measure, cloth masks should not be recommended for HCWs, particularly in high-risk situations, and guidelines need to be updated. Trial registration number Australian New Zealand Clinical Trials Registry: ACTRN12610000887077. PMID

  6. The Amygdala Is Involved in Affective Priming Effect for Fearful Faces

    ERIC Educational Resources Information Center

    Yang, J.; Cao, Z.; Xu, X.; Chen, G.

    2012-01-01

    The object of this study was to investigate whether the amygdala is involved in affective priming effect after stimuli are encoded unconsciously and consciously. During the encoding phase, each masked face (fearful or neutral) was presented to participants six times for 17 ms each, using a backward masking paradigm. During the retrieval phase,…

  7. Behind the mask. Journey through an epidemic: some observations of contrasting public health responses to SARS

    PubMed Central

    Syed, Q; Sopwith, W; Regan, M; Bellis, M

    2003-01-01

    SARS has been called the first global epidemic of the 21st century and has been the cause of a massive and varied public health response in many countries of the world. This report describes observations made by two authors on a journey from Manchester in the United Kingdom to Chiang Mai in Thailand during the peak of global transmission. The public response to SARS, particularly characterised by the wearing of face masks, seemed to outstrip official guidance. Though of uncertain protective benefit, the wearing of masks may have contributed to the awareness of the collective and personal responsibility in combating infectious disease. Active and empowered involvement of the general public in implementing and cooperating with public health control measures supported by national and international authorities has clearly helped to bring SARS under control. The public health significance of such potent symbols as the face mask may be considered in strategies to tackle other emerging infections. PMID:14600109

  8. Alternating phase-shifted mask for logic gate levels, design, and mask manufacturing

    NASA Astrophysics Data System (ADS)

    Liebmann, Lars W.; Graur, Ioana C.; Leipold, William C.; Oberschmidt, James M.; O'Grady, David S.; Regaill, Denis

    1999-07-01

    While the benefits of alternating phase shifted masks in improving lithographic process windows at increased resolution are well known throughout the lithography community, broad implementation of this potentially powerful technique has been slow due to the inherent complexity of the layout design and mask manufacturing process. This paper will review a project undertaken at IBM's Semiconductor Research and Development Center and Mask Manufacturing and Development facility to understand the technical and logistical issues associated with the application of alternating phase shifted mask technology to the gate level of a full microprocessor chip. The work presented here depicts an important milestone toward integration of alternating phase shifted masks into the manufacturing process by demonstrating an automated design solution and yielding a functional alternating phase shifted mask. The design conversion of the microprocessor gate level to a conjugate twin shifter alternating phase shift layout was accomplished with IBM's internal design system that automatically scaled the design, added required phase regions, and resolved phase conflicts. The subsequent fabrication of a nearly defect free phase shifted mask, as verified by SEM based die to die inspection, highlights the maturity of the alternating phase shifted mask manufacturing process in IBM's internal mask facility. Well defined and recognized challenges in mask inspection and repair remain and the layout of alternating phase shifted masks present a design and data preparation overhead, but the data presented here demonstrate the feasibility of designing and building manufacturing quality alternating phase shifted masks for the gate level of a microprocessor.

  9. Designing to win in sub-90nm mask production

    NASA Astrophysics Data System (ADS)

    Zhang, Yuan

    2005-11-01

    An informal survey conducted with key customers by Photronics indicates that the time gap between technology nodes has accelerated in recent years. Previously the cycle was three years. However, between 130nm and 90nm there was less than a 2 year gap, and between 90nm and 65nm a 1.5 year gap exists. As a result, the technical challenges have increased substantially. In addition, mask costs are rising exponentially due to high capital equipment cost, a shrinking customer base, long write times and increased applications of 193nm EAPSM or AAPSM. Collaboration among EDA companies, mask houses and wafer manufacturers is now more important than ever. This paper will explore avenues for reducing mask costs, mainly in the areas of: write-time reduction through design for manufacturing (DFM), and yield improvement through specification relaxation. Our study conducted through layout vertex modeling suggests that a simple design shape such as a square versus a circle or an angled structure helps reduce shot count and write time. Shot count reduction through mask layout optimization, and advancement in new generation E-beam writers can reduce write time up to 65%. An advanced laser writer can produce those less critical E-beam layers in less than half the time of an e-beam writer. Additionally, the emerging imprint lithography brings new life and new challenges to the photomask industry with applications in many fields outside of the semiconductor industry. As immersion lithography is introduced for 45nm device production, polarization and MEEF effects due to the mask will become severe. Larger magnification not only provides benefits on CD control and MEEF, but also extends the life time of current 90nm/65nm tool sets where 45nm mask sets can be produced at a lower cost.

  10. Hot-melt extrusion microencapsulation of quercetin for taste-masking.

    PubMed

    Khor, Chia Miang; Ng, Wai Kiong; Kanaujia, Parijat; Chan, Kok Ping; Dong, Yuancai

    2017-02-01

    Besides its poor dissolution rate, the bitterness of quercetin also poses a challenge for further development. Using carnauba wax, shellac or zein as the shell-forming excipient, this work aimed to microencapsulate quercetin by hot-melt extrusion for taste-masking. In comparison with non-encapsulated quercetin, the microencapsulated powders exhibited significantly reduced dissolution in the simulated salivary pH 6.8 medium indicative of their potentially good taste-masking efficiency in the order of zein > carnauba wax > shellac. In vitro bitterness analysis by electronic tongue confirmed the good taste-masking efficiency of the microencapsulated powders. In vitro digestion results showed that carnauba wax and shellac-microencapsulated powders presented comparable dissolution rate with the pure quercetin in pH 1.0 (gastric) and 6.8 (intestine) medium; while zein-microencapsulated powders exhibited a remarkably slower dissolution rate. Crystallinity of quercetin was slightly reduced after microencapsulation while its chemical structure remained unchanged. Hot-melt extrusion microencapsulation could thus be an attractive technique to produce taste-masked bioactive powders.

  11. A study of special care dental patient preference toward choice of mask and visor use by dental clinicians.

    PubMed

    Emanuel, Robert; Corcoran, Richard; Cass, Helen

    2017-07-01

    Do patients have a preference for the clinician's choice of face protection (visor or mask), and can this make a difference to the patient's feelings of anxiety? In a normative sample (n = 72) of patients from Special Care Dentistry, different combinations of face protection were studied to see whether the patients clearly preferred one type over another, and whether that was related to the levels of anxiety they suffered, based on the modified dental anxiety scale. The majority of patients, 68% had the visor only as their first choice of face protection. This was followed by 22% having the mask only as their first choice and 10% having the visor and mask combination as their first choice. Patients with higher anxiety levels were more likely to believe that the type of face protection worn by the dentist would affect their levels of anxiety. The patients preferred the visor only option. As the level of anxiety rose, so did the percentage of patients that felt the style of protection worn by the dentist would affect their level of anxiety. The comments from patients referred to the benefit of nonverbal communication offered by the visor. © 2017 Special Care Dentistry Association and Wiley Periodicals, Inc.

  12. Extension of optical lithography by mask-litho integration with computational lithography

    NASA Astrophysics Data System (ADS)

    Takigawa, T.; Gronlund, K.; Wiley, J.

    2010-05-01

    Wafer lithography process windows can be enlarged by using source mask co-optimization (SMO). Recently, SMO including freeform wafer scanner illumination sources has been developed. Freeform sources are generated by a programmable illumination system using a micro-mirror array or by custom Diffractive Optical Elements (DOE). The combination of freeform sources and complex masks generated by SMO show increased wafer lithography process window and reduced MEEF. Full-chip mask optimization using source optimized by SMO can generate complex masks with small variable feature size sub-resolution assist features (SRAF). These complex masks create challenges for accurate mask pattern writing and low false-defect inspection. The accuracy of the small variable-sized mask SRAF patterns is degraded by short range mask process proximity effects. To address the accuracy needed for these complex masks, we developed a highly accurate mask process correction (MPC) capability. It is also difficult to achieve low false-defect inspections of complex masks with conventional mask defect inspection systems. A printability check system, Mask Lithography Manufacturability Check (M-LMC), is developed and integrated with 199-nm high NA inspection system, NPI. M-LMC successfully identifies printable defects from all of the masses of raw defect images collected during the inspection of a complex mask. Long range mask CD uniformity errors are compensated by scanner dose control. A mask CD uniformity error map obtained by mask metrology system is used as input data to the scanner. Using this method, wafer CD uniformity is improved. As reviewed above, mask-litho integration technology with computational lithography is becoming increasingly important.

  13. Face detection and eyeglasses detection for thermal face recognition

    NASA Astrophysics Data System (ADS)

    Zheng, Yufeng

    2012-01-01

    Thermal face recognition becomes an active research direction in human identification because it does not rely on illumination condition. Face detection and eyeglasses detection are necessary steps prior to face recognition using thermal images. Infrared light cannot go through glasses and thus glasses will appear as dark areas in a thermal image. One possible solution is to detect eyeglasses and to exclude the eyeglasses areas before face matching. In thermal face detection, a projection profile analysis algorithm is proposed, where region growing and morphology operations are used to segment the body of a subject; then the derivatives of two projections (horizontal and vertical) are calculated and analyzed to locate a minimal rectangle of containing the face area. Of course, the searching region of a pair of eyeglasses is within the detected face area. The eyeglasses detection algorithm should produce either a binary mask if eyeglasses present, or an empty set if no eyeglasses at all. In the proposed eyeglasses detection algorithm, block processing, region growing, and priori knowledge (i.e., low mean and variance within glasses areas, the shapes and locations of eyeglasses) are employed. The results of face detection and eyeglasses detection are quantitatively measured and analyzed using the manually defined ground truths (for both face and eyeglasses). Our experimental results shown that the proposed face detection and eyeglasses detection algorithms performed very well in contrast with the predefined ground truths.

  14. Mask process correction (MPC) modeling and its application to EUV mask for electron beam mask writer EBM-7000

    NASA Astrophysics Data System (ADS)

    Kamikubo, Takashi; Ohnishi, Takayuki; Hara, Shigehiro; Anze, Hirohito; Hattori, Yoshiaki; Tamamushi, Shuichi; Bai, Shufeng; Wang, Jen-Shiang; Howell, Rafael; Chen, George; Li, Jiangwei; Tao, Jun; Wiley, Jim; Kurosawa, Terunobu; Saito, Yasuko; Takigawa, Tadahiro

    2010-09-01

    In electron beam writing on EUV mask, it has been reported that CD linearity does not show simple signatures as observed with conventional COG (Cr on Glass) masks because they are caused by scattered electrons form EUV mask itself which comprises stacked heavy metals and thick multi-layers. To resolve this issue, Mask Process Correction (MPC) will be ideally applicable. Every pattern is reshaped in MPC. Therefore, the number of shots would not increase and writing time will be kept within reasonable range. In this paper, MPC is extended to modeling for correction of CD linearity errors on EUV mask. And its effectiveness is verified with simulations and experiments through actual writing test.

  15. The Combined Tool Approach for Face Mask Removal During On-field Conditions

    PubMed Central

    Gale, Stephanie D; Decoster, Laura C; Swartz, Erik E

    2008-01-01

    Context: An effective approach to emergency removal of the face mask (FM) from a football helmet should include successful removal of the FM and limitation of both the time required and the movement created during the process. Current recommendations and practice are to use a cutting tool to remove the FM. Researchers recently have suggested an alternate approach that combines the use of a cordless screwdriver and a cutting tool. This combined tool approach has not been studied, and FM removal has not been studied in a practical setting. Objective: To investigate the effectiveness and speed of using a combined tool approach to remove the FMs from football helmets during on-field conditions throughout the course of a football season. Design: Randomized multigroup design. Setting: Practice field of 1 National Collegiate Athletic Association Division II football college. Patients or Other Participants: Eighty-four members of 1 football team. Intervention(s): We used a battery-operated screwdriver for FM removal and resorted to using a cutting tool as needed. Main Outcome Measure(s): We tracked FM removal success and failure and trial time and compared results based on helmet characteristics, weather variables, and the seasonal timing of the removal trial. Results: Of the 84 players, 76 were available for data-collection trials. Overall, 98.6% (75/76) of FM removal trials were successful and resulted in a mean removal time of 40.09 ± 15.1 seconds. We found no differences in FM removal time throughout the course of the season. No differences in effectiveness or trial time were found among helmet characteristics, weather variables, or the timing of the trial. Conclusions: Combining the cordless screwdriver and cutting tool provided a fast and reliable means of on-field FM removal in this Division II setting. Despite the excellent overall result, 1 FM was not removed in a timely manner. Therefore, we recommend that athletic trainers practice helmet removal to be prepared

  16. System for generating two-dimensional masks from a three-dimensional model using topological analysis

    DOEpatents

    Schiek, Richard [Albuquerque, NM

    2006-06-20

    A method of generating two-dimensional masks from a three-dimensional model comprises providing a three-dimensional model representing a micro-electro-mechanical structure for manufacture and a description of process mask requirements, reducing the three-dimensional model to a topological description of unique cross sections, and selecting candidate masks from the unique cross sections and the cross section topology. The method further can comprise reconciling the candidate masks based on the process mask requirements description to produce two-dimensional process masks.

  17. Understanding and reduction of defects on finished EUV masks

    NASA Astrophysics Data System (ADS)

    Liang, Ted; Sanchez, Peter; Zhang, Guojing; Shu, Emily; Nagpal, Rajesh; Stivers, Alan

    2005-05-01

    To reduce the risk of EUV lithography adaptation for the 32nm technology node in 2009, Intel has operated a EUV mask Pilot Line since early 2004. The Pilot Line integrates all the necessary process modules including common tool sets shared with current photomask production as well as EUV specific tools. This integrated endeavor ensures a comprehensive understanding of any issues, and development of solutions for the eventual fabrication of defect-free EUV masks. Two enabling modules for "defect-free" masks are pattern inspection and repair, which have been integrated into the Pilot Line. This is the first time we are able to look at real defects originated from multilayer blanks and patterning process on finished masks over entire mask area. In this paper, we describe our efforts in the qualification of DUV pattern inspection and electron beam mask repair tools for Pilot Line operation, including inspection tool sensitivity, defect classification and characterization, and defect repair. We will discuss the origins of each of the five classes of defects as seen by DUV pattern inspection tool on finished masks, and present solutions of eliminating and mitigating them.

  18. Multiple beam mask writers: an industry solution to the write time crisis

    NASA Astrophysics Data System (ADS)

    Litt, Lloyd C.

    2010-09-01

    The semiconductor industry is under constant pressure to reduce production costs even as technology complexity increases. Lithography represents the most expensive process due to its high capital equipment costs and the implementation of low-k1 lithographic processes, which has added to the complexity of making masks through the greater use of optical proximity correction, pixelated masks, and double or triple patterning. Each of these mask technologies allows the production of semiconductors at future nodes while extending the utility of current immersion tools. Low k1 patterning complexity combined with increased data due to smaller feature sizes is driving extremely long mask write times. While a majority of the industry is willing to accept mask write times of up to 24 hours, evidence suggests that the write times for many masks at the 22 nm node and beyond will be significantly longer. It has been estimated that $50M+ in non-recurring engineering (NRE) costs will be required to develop a multiple beam mask writer system, yet the business case to recover this kind of investment is not strong. Moreover, funding such a development is a high risk for an individual supplier. The problem is compounded by a disconnect between the tool customer (the mask supplier) and the final mask customer that will bear the increased costs if a high speed writer is not available. Since no individual company will likely risk entering this market, some type of industry-wide funding model will be needed. Because SEMATECH's member companies strongly support a multiple beam technology for mask writers to reduce the write time and cost of 193 nm and EUV masks, SEMATECH plans to pursue an advanced mask writer program in 2011 and 2012. In 2010, efforts will focus on identifying a funding model to address the investment to develop such a technology.

  19. Equivalence of nasal and oronasal masks during initial CPAP titration for obstructive sleep apnea syndrome.

    PubMed

    Teo, Ming; Amis, Terence; Lee, Sharon; Falland, Karina; Lambert, Stephen; Wheatley, John

    2011-07-01

    Continuous positive airway pressure (CPAP) titration studies are commonly performed using a nasal mask but some patients may prefer a full-face or oronasal mask. There is little evidence regarding the equivalence of different mask interfaces used to initiate treatment. We hypothesized that oronasal breathing when using an oronasal mask increases upper airway collapsibility and that a higher pressure may be required to maintain airway patency. We also assessed patient preferences for the 2 mask interfaces. Prospective, randomized, cross-over design with 2 consecutive CPAP titration nights. Accredited laboratory in a university hospital. Twenty-four treatment-naive subjects with obstructive sleep apnea syndrome and respiratory disturbance index of greater than 15 events per hour. CPAP titration was performed using an auto-titrating machine with randomization to a nasal or oronasal mask, followed by a second titration night using the alternate mask style. There was no significant difference in the mean pressures determined between nasal and oronasal masks, although 43% of subjects had nasal-to-oronasal mask-pressure differences of 2 cm H(2)O or more. Residual respiratory events, arousals, and measured leak were all greater with the oronasal mask. Seventy-nine percent of subjects preferred the nasal mask. Patients with obstructive sleep apnea syndrome can generally switch between nasal and oronasal masks without changing machine pressure, although there are individual differences that may be clinically significant. Measured leak is greater with the oronasal mask. Most patients with obstructive sleep apnea syndrome prefer a nasal mask as the interface for initiation of CPAP. Australian New Zealand Clinical Trials Registry (ANZCTR). ACTRN: ACTRN12611000243910. URL: http://www.ANZCTR.org.au/ACTRN12611000243910.aspx

  20. Six-month-old infants' perception of the hollow face illusion: evidence for a general convexity bias.

    PubMed

    Corrow, Sherryse L; Mathison, Jordan; Granrud, Carl E; Yonas, Albert

    2014-01-01

    Corrow, Granrud, Mathison, and Yonas (2011, Perception, 40, 1376-1383) found evidence that 6-month-old infants perceive the hollow face illusion. In the present study we asked whether 6-month-old infants perceive illusory depth reversal for a nonface object and whether infants' perception of the hollow face illusion is affected by mask orientation inversion. In experiment 1 infants viewed a concave bowl, and their reaches were recorded under monocular and binocular viewing conditions. Infants reached to the bowl as if it were convex significantly more often in the monocular than in the binocular viewing condition. These results suggest that infants perceive illusory depth reversal with a nonface stimulus and that the infant visual system has a bias to perceive objects as convex. Infants in experiment 2 viewed a concave face-like mask in upright and inverted orientations. Infants reached to the display as if it were convex more in the monocular than in the binocular condition; however, mask orientation had no effect on reaching. Previous findings that adults' perception of the hollow face illusion is affected by mask orientation inversion have been interpreted as evidence of stored-knowledge influences on perception. However, we found no evidence of such influences in infants, suggesting that their perception of this illusion may not be affected by stored knowledge, and that perceived depth reversal is not face-specific in infants.

  1. Masked multichannel analyzer

    DOEpatents

    Winiecki, A.L.; Kroop, D.C.; McGee, M.K.; Lenkszus, F.R.

    1984-01-01

    An analytical instrument and particularly a time-of-flight-mass spectrometer for processing a large number of analog signals irregularly spaced over a spectrum, with programmable masking of portions of the spectrum where signals are unlikely in order to reduce memory requirements and/or with a signal capturing assembly having a plurality of signal capturing devices fewer in number than the analog signals for use in repeated cycles within the data processing time period.

  2. Masked multichannel analyzer

    DOEpatents

    Winiecki, Alan L.; Kroop, David C.; McGee, Marilyn K.; Lenkszus, Frank R.

    1986-01-01

    An analytical instrument and particularly a time-of-flight-mass spectrometer for processing a large number of analog signals irregularly spaced over a spectrum, with programmable masking of portions of the spectrum where signals are unlikely in order to reduce memory requirements and/or with a signal capturing assembly having a plurality of signal capturing devices fewer in number than the analog signals for use in repeated cycles within the data processing time period.

  3. Performance of ICU ventilators during noninvasive ventilation with large leaks in a total face mask: a bench study.

    PubMed

    Nakamura, Maria Aparecida Miyuki; Costa, Eduardo Leite Vieira; Carvalho, Carlos Roberto Ribeiro; Tucci, Mauro Roberto

    2014-01-01

    Discomfort and noncompliance with noninvasive ventilation (NIV) interfaces are obstacles to NIV success. Total face masks (TFMs) are considered to be a very comfortable NIV interface. However, due to their large internal volume and consequent increased CO2 rebreathing, their orifices allow proximal leaks to enhance CO2 elimination. The ventilators used in the ICU might not adequately compensate for such leakage. In this study, we attempted to determine whether ICU ventilators in NIV mode are suitable for use with a leaky TFM. This was a bench study carried out in a university research laboratory. Eight ICU ventilators equipped with NIV mode and one NIV ventilator were connected to a TFM with major leaks. All were tested at two positive end-expiratory pressure (PEEP) levels and three pressure support levels. The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization. Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly. The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM.

  4. Performance of ICU ventilators during noninvasive ventilation with large leaks in a total face mask: a bench study* **

    PubMed Central

    Nakamura, Maria Aparecida Miyuki; Costa, Eduardo Leite Vieira; Carvalho, Carlos Roberto Ribeiro; Tucci, Mauro Roberto

    2014-01-01

    Objective: Discomfort and noncompliance with noninvasive ventilation (NIV) interfaces are obstacles to NIV success. Total face masks (TFMs) are considered to be a very comfortable NIV interface. However, due to their large internal volume and consequent increased CO2 rebreathing, their orifices allow proximal leaks to enhance CO2 elimination. The ventilators used in the ICU might not adequately compensate for such leakage. In this study, we attempted to determine whether ICU ventilators in NIV mode are suitable for use with a leaky TFM. Methods: This was a bench study carried out in a university research laboratory. Eight ICU ventilators equipped with NIV mode and one NIV ventilator were connected to a TFM with major leaks. All were tested at two positive end-expiratory pressure (PEEP) levels and three pressure support levels. The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization. Results: Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly. Conclusions: The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM. PMID:25029653

  5. 2013 mask industry survey

    NASA Astrophysics Data System (ADS)

    Malloy, Matt

    2013-09-01

    A comprehensive survey was sent to merchant and captive mask shops to gather information about the mask industry as an objective assessment of its overall condition. 2013 marks the 12th consecutive year for this process. Historical topics including general mask profile, mask processing, data and write time, yield and yield loss, delivery times, maintenance, and returns were included and new topics were added. Within each category are multiple questions that result in a detailed profile of both the business and technical status of the mask industry. While each year's survey includes minor updates based on feedback from past years and the need to collect additional data on key topics, the bulk of the survey and reporting structure have remained relatively constant. A series of improvements is being phased in beginning in 2013 to add value to a wider audience, while at the same time retaining the historical content required for trend analyses of the traditional metrics. Additions in 2013 include topics such as top challenges, future concerns, and additional details in key aspects of mask masking, such as the number of masks per mask set per ground rule, minimum mask resolution shipped, and yield by ground rule. These expansions beyond the historical topics are aimed at identifying common issues, gaps, and needs. They will also provide a better understanding of real-life mask requirements and capabilities for comparison to the International Technology Roadmap for Semiconductors (ITRS).

  6. Effects of hard mask etch on final topography of advanced phase shift masks

    NASA Astrophysics Data System (ADS)

    Hortenbach, Olga; Rolff, Haiko; Lajn, Alexander; Baessler, Martin

    2017-07-01

    Continuous shrinking of the semiconductor device dimensions demands steady improvements of the lithographic resolution on wafer level. These requirements challenge the photomask industry to further improve the mask quality in all relevant printing characteristics. In this paper topography of the Phase Shift Masks (PSM) was investigated. Effects of hard mask etch on phase shift uniformity and mask absorber profile were studied. Design of experiments method (DoE) was used for the process optimization, whereas gas composition, bias power of the hard mask main etch and bias power of the over-etch were varied. In addition, influence of the over-etch time was examined at the end of the experiment. Absorber depth uniformity, sidewall angle (SWA), reactive ion etch lag (RIE lag) and through pitch (TP) dependence were analyzed. Measurements were performed by means of Atomic-force microscopy (AFM) using critical dimension (CD) mode with a boot-shaped tip. Scanning electron microscope (SEM) cross-section images were prepared to verify the profile quality. Finally CD analysis was performed to confirm the optimal etch conditions. Significant dependence of the absorber SWA on hard mask (HM) etch conditions was observed revealing an improvement potential for the mask absorber profile. It was found that hard mask etch can leave a depth footprint in the absorber layer. Thus, the etch depth uniformity of hard mask etch is crucial for achieving a uniform phase shift over the active mask area. The optimized hard mask etch process results in significantly improved mask topography without deterioration of tight CD specifications.

  7. Three-dimensional printing for restoration of the donor face: A new digital technique tested and used in the first facial allotransplantation patient in Finland.

    PubMed

    Mäkitie, A A; Salmi, M; Lindford, A; Tuomi, J; Lassus, P

    2016-12-01

    Prosthetic mask restoration of the donor face is essential in current facial transplant protocols. The aim was to develop a new three-dimensional (3D) printing (additive manufacturing; AM) process for the production of a donor face mask that fulfilled the requirements for facial restoration after facial harvest. A digital image of a single test person's face was obtained in a standardized setting and subjected to three different image processing techniques. These data were used for the 3D modeling and printing of a donor face mask. The process was also tested in a cadaver setting and ultimately used clinically in a donor patient after facial allograft harvest. and Conclusions: All the three developed and tested techniques enabled the 3D printing of a custom-made face mask in a timely manner that is almost an exact replica of the donor patient's face. This technique was successfully used in a facial allotransplantation donor patient. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  8. Masking Period Patterns & Forward Masking for Speech-Shaped Noise: Age-related effects

    PubMed Central

    Grose, John H.; Menezes, Denise C.; Porter, Heather L.; Griz, Silvana

    2015-01-01

    Objective The purpose of this study was to assess age-related changes in temporal resolution in listeners with relatively normal audiograms. The hypothesis was that increased susceptibility to non-simultaneous masking contributes to the hearing difficulties experienced by older listeners in complex fluctuating backgrounds. Design Participants included younger (n = 11), middle-aged (n = 12), and older (n = 11) listeners with relatively normal audiograms. The first phase of the study measured masking period patterns for speech-shaped noise maskers and signals. From these data, temporal window shapes were derived. The second phase measured forward-masking functions, and assessed how well the temporal window fits accounted for these data. Results The masking period patterns demonstrated increased susceptibility to backward masking in the older listeners, compatible with a more symmetric temporal window in this group. The forward-masking functions exhibited an age-related decline in recovery to baseline thresholds, and there was also an increase in the variability of the temporal window fits to these data. Conclusions This study demonstrated an age-related increase in susceptibility to non-simultaneous masking, supporting the hypothesis that exacerbated non-simultaneous masking contributes to age-related difficulties understanding speech in fluctuating noise. Further support for this hypothesis comes from limited speech-in-noise data suggesting an association between susceptibility to forward masking and speech understanding in modulated noise. PMID:26230495

  9. Exploiting Small Leakages in Masks to Turn a Second-Order Attack into a First-Order Attack and Improved Rotating Substitution Box Masking with Linear Code Cosets.

    PubMed

    DeTrano, Alexander; Karimi, Naghmeh; Karri, Ramesh; Guo, Xiaofei; Carlet, Claude; Guilley, Sylvain

    2015-01-01

    Masking countermeasures, used to thwart side-channel attacks, have been shown to be vulnerable to mask-extraction attacks. State-of-the-art mask-extraction attacks on the Advanced Encryption Standard (AES) algorithm target S-Box recomputation schemes but have not been applied to scenarios where S-Boxes are precomputed offline. We propose an attack targeting precomputed S-Boxes stored in nonvolatile memory. Our attack targets AES implemented in software protected by a low entropy masking scheme and recovers the masks with 91% success rate. Recovering the secret key requires fewer power traces (in fact, by at least two orders of magnitude) compared to a classical second-order attack. Moreover, we show that this attack remains viable in a noisy environment or with a reduced number of leakage points. Eventually, we specify a method to enhance the countermeasure by selecting a suitable coset of the masks set.

  10. Exploiting Small Leakages in Masks to Turn a Second-Order Attack into a First-Order Attack and Improved Rotating Substitution Box Masking with Linear Code Cosets

    PubMed Central

    DeTrano, Alexander; Karimi, Naghmeh; Karri, Ramesh; Guo, Xiaofei; Carlet, Claude; Guilley, Sylvain

    2015-01-01

    Masking countermeasures, used to thwart side-channel attacks, have been shown to be vulnerable to mask-extraction attacks. State-of-the-art mask-extraction attacks on the Advanced Encryption Standard (AES) algorithm target S-Box recomputation schemes but have not been applied to scenarios where S-Boxes are precomputed offline. We propose an attack targeting precomputed S-Boxes stored in nonvolatile memory. Our attack targets AES implemented in software protected by a low entropy masking scheme and recovers the masks with 91% success rate. Recovering the secret key requires fewer power traces (in fact, by at least two orders of magnitude) compared to a classical second-order attack. Moreover, we show that this attack remains viable in a noisy environment or with a reduced number of leakage points. Eventually, we specify a method to enhance the countermeasure by selecting a suitable coset of the masks set. PMID:26491717

  11. Impairment of holistic face perception following right occipito-temporal damage in prosopagnosia: converging evidence from gaze-contingency.

    PubMed

    Van Belle, Goedele; Busigny, Thomas; Lefèvre, Philippe; Joubert, Sven; Felician, Olivier; Gentile, Francesco; Rossion, Bruno

    2011-09-01

    Gaze-contingency is a method traditionally used to investigate the perceptual span in reading by selectively revealing/masking a portion of the visual field in real time. Introducing this approach in face perception research showed that the performance pattern of a brain-damaged patient with acquired prosopagnosia (PS) in a face matching task was reversed, as compared to normal observers: the patient showed almost no further decrease of performance when only one facial part (eye, mouth, nose, etc.) was available at a time (foveal window condition, forcing part-based analysis), but a very large impairment when the fixated part was selectively masked (mask condition, promoting holistic perception) (Van Belle, De Graef, Verfaillie, Busigny, & Rossion, 2010a; Van Belle, De Graef, Verfaillie, Rossion, & Lefèvre, 2010b). Here we tested the same manipulation in a recently reported case of pure prosopagnosia (GG) with unilateral right hemisphere damage (Busigny, Joubert, Felician, Ceccaldi, & Rossion, 2010). Contrary to normal observers, GG was also significantly more impaired with a mask than with a window, demonstrating impairment with holistic face perception. Together with our previous study, these observations support a generalized account of acquired prosopagnosia as a critical impairment of holistic (individual) face perception, implying that this function is a key element of normal human face recognition. Furthermore, the similar behavioral pattern of the two patients despite different lesion localizations supports a distributed network view of the neural face processing structures, suggesting that the key function of human face processing, namely holistic perception of individual faces, requires the activity of several brain areas of the right hemisphere and their mutual connectivity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Reduced set averaging of face identity in children and adolescents with autism.

    PubMed

    Rhodes, Gillian; Neumann, Markus F; Ewing, Louise; Palermo, Romina

    2015-01-01

    Individuals with autism have difficulty abstracting and updating average representations from their diet of faces. These averages function as perceptual norms for coding faces, and poorly calibrated norms may contribute to face recognition difficulties in autism. Another kind of average, known as an ensemble representation, can be abstracted from briefly glimpsed sets of faces. Here we show for the first time that children and adolescents with autism also have difficulty abstracting ensemble representations from sets of faces. On each trial, participants saw a study set of four identities and then indicated whether a test face was present. The test face could be a set average or a set identity, from either the study set or another set. Recognition of set averages was reduced in participants with autism, relative to age- and ability-matched typically developing participants. This difference, which actually represents more accurate responding, indicates weaker set averaging and thus weaker ensemble representations of face identity in autism. Our finding adds to the growing evidence for atypical abstraction of average face representations from experience in autism. Weak ensemble representations may have negative consequences for face processing in autism, given the importance of ensemble representations in dealing with processing capacity limitations.

  13. Factors responsible for remote-frequency masking in children and adultsa)

    PubMed Central

    Leibold, Lori J.; Buss, Emily

    2016-01-01

    Susceptibility to remote-frequency masking in children and adults was evaluated with respect to three stimulus features: (1) masker bandwidth, (2) spectral separation of the signal and masker, and (3) gated versus continuous masker presentation. Listeners were 4- to 6-year-olds, 7- to 10-year-olds, and adults. Detection thresholds for a 500-ms, 2000-Hz signal were estimated in quiet or presented with a band of noise in one of four frequency regions: 425–500 Hz, 4000–4075 Hz, 8000–8075 Hz, or 4000–10 000 Hz. In experiment 1, maskers were gated on in each 500-ms interval of a three-interval, forced-choice adaptive procedure. Masking was observed for all ages in all maskers, but the greatest masking was observed for the 4000–4075 Hz masker. These findings suggest that signal/masker spectral proximity plays an important role in remote-frequency masking, even when peripheral excitation associated with the signal and masker does not overlap. Younger children tended to have more masking than older children or adults, consistent with a reduced ability to segregate simultaneous sounds and/or listen in a frequency-selective manner. In experiment 2, detection thresholds were estimated in the same noises, but maskers were presented continuously. Masking was reduced for all ages relative to gated conditions, suggesting improved segregation and/or frequency-selective listening. PMID:28040030

  14. The Role of Eyes and Mouth in the Memory of a Face

    ERIC Educational Resources Information Center

    McKelvie, Stuart J.

    1976-01-01

    Investigates the relative importance that the eyes and mouth play in the representation in memory of a human face. Systematically applies two kinds of transformation--masking the eyes or the mouths on photographs of faces--and observes the effects on recognition. (Author/RK)

  15. Manufacturability study of masks created by inverse lithography technology (ILT)

    NASA Astrophysics Data System (ADS)

    Martin, Patrick M.; Progler, C. J.; Xiao, G.; Gray, R.; Pang, L.; Liu, Y.

    2005-11-01

    As photolithography is pushed to fabricate deep-sub wavelength devices for 90nm, 65nm and smaller technology nodes using available exposure tools (i.e., 248nm, 193nm steppers), photomask capability is becoming extremely critical. For example, PSM masks require more complicated processing; aggressive OPC makes the writing time longer and sometimes unpredictable; and, high MEEF imposes much more stringent demands on mask quality. Therefore, in order for any new lithography technology to be adopted into production, mask manufacturability must be studied thoroughly and carefully. In this paper we will present the mask manufacturability study on mask patterns created using Inverse Lithography Technology (ILT). Unlike conventional OPC methodologies, ILT uses a unique outcome-based technology to mathematically determine the mask features that produce the desired on-wafer results. ILT solves the most critical litho challenges of the deep sub-wavelength era. Potential benefits include: higher yield; expanded litho process windows; superb pattern fidelity at 90, 65 & 45-nm nodes; and reduced time-to-silicon - all without changing the existing lithography infrastructure and design-to-silicon flow. In this study a number of cell structures were selected and used as test patterns. "Luminized patterns" were generated for binary mask and attenuated phase-shift mask. Both conventional OPC patterns and "luminized patterns" were put on a test reticle side by side, and they all have a number of variations in term of correction aggressivity level and mask complexity. Mask manufacturability, including data fracturing, writing time, mask inspection, and metrology were studied. The results demonstrate that, by optimizing the inspection recipe, masks created using ILT technology can be made and qualified using current processes with a reasonable turn-around time.

  16. What Is Being Masked in Object Substitution Masking?

    ERIC Educational Resources Information Center

    Gellatly, Angus; Pilling, Michael; Cole, Geoff; Skarratt, Paul

    2006-01-01

    Object substitution masking (OSM) is said to occur when a perceptual object is hypothesized that is mismatched by subsequent sensory evidence, leading to a new hypothesized object being substituted for the first. For example, when a brief target is accompanied by a longer lasting display of nonoverlapping mask elements, reporting of target…

  17. Masking Period Patterns and Forward Masking for Speech-Shaped Noise: Age-Related Effects.

    PubMed

    Grose, John H; Menezes, Denise C; Porter, Heather L; Griz, Silvana

    2016-01-01

    The purpose of this study was to assess age-related changes in temporal resolution in listeners with relatively normal audiograms. The hypothesis was that increased susceptibility to nonsimultaneous masking contributes to the hearing difficulties experienced by older listeners in complex fluctuating backgrounds. Participants included younger (n = 11), middle-age (n = 12), and older (n = 11) listeners with relatively normal audiograms. The first phase of the study measured masking period patterns for speech-shaped noise maskers and signals. From these data, temporal window shapes were derived. The second phase measured forward-masking functions and assessed how well the temporal window fits accounted for these data. The masking period patterns demonstrated increased susceptibility to backward masking in the older listeners, compatible with a more symmetric temporal window in this group. The forward-masking functions exhibited an age-related decline in recovery to baseline thresholds, and there was also an increase in the variability of the temporal window fits to these data. This study demonstrated an age-related increase in susceptibility to nonsimultaneous masking, supporting the hypothesis that exacerbated nonsimultaneous masking contributes to age-related difficulties understanding speech in fluctuating noise. Further support for this hypothesis comes from limited speech-in-noise data, suggesting an association between susceptibility to forward masking and speech understanding in modulated noise.

  18. A single administration of cortisol acutely reduces preconscious attention for fear in anxious young men.

    PubMed

    Putman, Peter; Hermans, Erno J; Koppeschaar, Hans; van Schijndel, Alexandra; van Honk, Jack

    2007-08-01

    Chronically elevated HPA activity has often been associated with fear and anxiety, but there is evidence that single administrations of glucocorticoids may acutely reduce fear. Moreover, peri-traumatic cortisol elevation may protect against development of post-traumatic stress disorder. Hypervigilant processing of threat information plays a role in anxiety disorders and although relations with HPA functioning have been established, causality of these relations remains unclear. Presently, self-reported anxiety and response time patterns on a masked emotional Stroop task with fearful faces were measured in 20 healthy young men after double-blind, placebo-controlled oral administration of 40 mg cortisol. The masked fearful Stroop task measures vocal colornaming response latencies for pictures of neutral and fearful faces presented below the threshold for conscious perception. Results showed increased response times on trials for fearful compared to neutral faces after placebo, but this emotional Stroop effect was acutely abolished by cortisol administration. This effect was most pronounced in subjects with heightened anxiety levels. This is the first evidence showing that exogenous cortisol acutely reduces anxiety-driven selective attention to threat. These results extend earlier findings of acute fear reduction after glucocorticoid administration. This suggests interactions of HPA functioning and vigilant attention in the pathogenesis of anxiety disorders. Possible neuroendocrine mechanisms of action are discussed.

  19. 2012 Mask Industry Survey

    NASA Astrophysics Data System (ADS)

    Malloy, Matt; Litt, Lloyd C.

    2012-11-01

    A survey supported by SEMATECH and administered by David Powell Consulting was sent to semiconductor industry leaders to gather information about the mask industry as an objective assessment of its overall condition. The survey was designed with the input of semiconductor company mask technologists and merchant mask suppliers. 2012 marks the 11th consecutive year for the mask industry survey. This year's survey and reporting structure are similar to those of the previous years with minor modifications based on feedback from past years and the need to collect additional data on key topics. Categories include general mask information, mask processing, data and write time, yield and yield loss, delivery times, and maintenance and returns. Within each category are multiple questions that result in a detailed profile of both the business and technical status of the mask industry. Results, initial observations, and key comparisons between the 2011 and 2012 survey responses are shown here, including multiple indications of a shift towards the manufacturing of higher end photomasks.

  20. Using a high-flow nasal cannula provides superior results to OxyMask delivery in moderate to severe bronchiolitis: a randomized controlled study.

    PubMed

    Ergul, Ayse Betul; Calıskan, Emrah; Samsa, Hasan; Gokcek, Ikbal; Kaya, Ali; Zararsiz, Gozde Erturk; Torun, Yasemin Altuner

    2018-06-18

    The effectiveness of using a face mask with a small diffuser for oxygen delivery (OxyMask) was compared to use of a high-flow nasal cannula (HFNC) in patients with moderate or severe bronchiolitis.The study population in this open, phase 4, randomized controlled trial consisted of 60 patients aged 1-24 months diagnosed with moderate or severe bronchiolitis and admitted to an intensive care unit (ICU) for oxygen therapy. The patients were randomized into two groups according to the method of oxygen delivery: a diffuser mask group and an HFNC group.There were seven failures in the mask group and none in the HFNC group. The survival probability differed significantly between the two treatment methods (p = 0.009).Time to weaning off oxygen therapy was 56 h in the HFNC group and 96 h in the mask group (p < 0.001). HFNC use decreased the treatment failure rate and the duration of both oxygen therapy and ICU treatment compared to the diffuser mask, which implies that an HFNC should be the first choice for treating patients admitted to the ICU with severe bronchiolitis. What is known: • A high-flow nasal cannula (HFNC) does not significantly reduce the time on oxygen compared to standard therapy in children with moderate to severe bronchiolitis. Observational studies show that, since the introduction of HFNC, fewer children with bronchiolitis need intubation. For children with moderate to severe bronchiolitis there is no proof of its benefit. What Is New: • In children with moderate to severe bronchiolitis, HFNC provides faster and more effective improvement than can be achieved with a diffuser mask.

  1. Beyond a mask and against the bottleneck: retroactive dual-task interference during working memory consolidation of a masked visual target.

    PubMed

    Nieuwenstein, Mark; Wyble, Brad

    2014-06-01

    While studies on visual memory commonly assume that the consolidation of a visual stimulus into working memory is interrupted by a trailing mask, studies on dual-task interference suggest that the consolidation of a stimulus can continue for several hundred milliseconds after a mask. As a result, estimates of the time course of working memory consolidation differ more than an order of magnitude. Here, we contrasted these opposing views by examining if and for how long the processing of a masked display of visual stimuli can be disturbed by a trailing 2-alternative forced choice task (2-AFC; a color discrimination task or a visual or auditory parity judgment task). The results showed that the presence of the 2-AFC task produced a pronounced retroactive interference effect that dissipated across stimulus onset asynchronies of 250-1,000 ms, indicating that the processing elicited by the 2-AFC task interfered with the gradual consolidation of the earlier shown stimuli. Furthermore, this interference effect occurred regardless of whether the to-be-remembered stimuli comprised a string of letters or an unfamiliar complex visual shape, and it occurred regardless of whether these stimuli were masked. Conversely, the interference effect was reduced when the memory load for the 1st task was reduced, or when the 2nd task was a color detection task that did not require decision making. Taken together, these findings show that the formation of a durable and consciously accessible working memory trace for a briefly shown visual stimulus can be disturbed by a trailing 2-AFC task for up to several hundred milliseconds after the stimulus has been masked. By implication, the current findings challenge the common view that working memory consolidation involves an immutable central processing bottleneck, and they also make clear that consolidation does not stop when a stimulus is masked. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  2. Creation of Prototype Aircrew Protection Equipment Based on Face Anthropometry

    DTIC Science & Technology

    1993-12-01

    AD-A273 865 AFIT/GSE/ENY/93D-2AD 27 86 DTIC ELECTE SDE.C 161993 A : CREATION OF PROTOTYPE AIRCREW PROTECTION EQUIPMENT BASED ON FACE ANTHROPOMETRY ...AIRCREW PROTECTION EQUIPMENT BASED ON FACE ANTHROPOMETRY THESIS Presented to the Faculty of the Graduate School of Engineering of the Air Force Institute...trans- form anthropomorphic surfaces into a prototype mask mold. xix CREATION OF PROTOTYPE AIRCREW PROTECTION EQUIPMENT BASED ON FACE ANTHROPOMETRY L

  3. Maximizing noise energy for noise-masking studies.

    PubMed

    Jules Étienne, Cédric; Arleo, Angelo; Allard, Rémy

    2017-08-01

    Noise-masking experiments are widely used to investigate visual functions. To be useful, noise generally needs to be strong enough to noticeably impair performance, but under some conditions, noise does not impair performance even when its contrast approaches the maximal displayable limit of 100 %. To extend the usefulness of noise-masking paradigms over a wider range of conditions, the present study developed a noise with great masking strength. There are two typical ways of increasing masking strength without exceeding the limited contrast range: use binary noise instead of Gaussian noise or filter out frequencies that are not relevant to the task (i.e., which can be removed without affecting performance). The present study combined these two approaches to further increase masking strength. We show that binarizing the noise after the filtering process substantially increases the energy at frequencies within the pass-band of the filter given equated total contrast ranges. A validation experiment showed that similar performances were obtained using binarized-filtered noise and filtered noise (given equated noise energy at the frequencies within the pass-band) suggesting that the binarization operation, which substantially reduced the contrast range, had no significant impact on performance. We conclude that binarized-filtered noise (and more generally, truncated-filtered noise) can substantially increase the energy of the noise at frequencies within the pass-band. Thus, given a limited contrast range, binarized-filtered noise can display higher energy levels than Gaussian noise and thereby widen the range of conditions over which noise-masking paradigms can be useful.

  4. Robust source and mask optimization compensating for mask topography effects in computational lithography.

    PubMed

    Li, Jia; Lam, Edmund Y

    2014-04-21

    Mask topography effects need to be taken into consideration for a more accurate solution of source mask optimization (SMO) in advanced optical lithography. However, rigorous 3D mask models generally involve intensive computation and conventional SMO fails to manipulate the mask-induced undesired phase errors that degrade the usable depth of focus (uDOF) and process yield. In this work, an optimization approach incorporating pupil wavefront aberrations into SMO procedure is developed as an alternative to maximize the uDOF. We first design the pupil wavefront function by adding primary and secondary spherical aberrations through the coefficients of the Zernike polynomials, and then apply the conjugate gradient method to achieve an optimal source-mask pair under the condition of aberrated pupil. We also use a statistical model to determine the Zernike coefficients for the phase control and adjustment. Rigorous simulations of thick masks show that this approach provides compensation for mask topography effects by improving the pattern fidelity and increasing uDOF.

  5. Impact of different nasal masks on CPAP therapy for obstructive sleep apnea: a randomized comparative trial.

    PubMed

    Neuzeret, Pierre-Charles; Morin, Laurent

    2017-11-01

    Patient interface is important for the success of continuous positive airway pressure (CPAP), but few trials have examined the influence of mask choice on CPAP adherence. To compare the impact of different nasal masks on CPAP in patients with newly-diagnosed obstructive sleep apnea (OSA). OSA patients were randomized in a 2:3 ratio to receive CPAP via different first-line nasal masks: ResMed Mirage FX® (MFX) or control mask (Fisher & Paykel Zest ® , HC407 ® or Philips EasyLife ® ). Mask acceptance, CPAP compliance and Home Care Provider (HCP) interventions were compared between groups after 3 months of CPAP therapy using modified intent-to-treat (mITT; after exclusion of patients with mouth leaks during CPAP initiation) and on-treatment (OT; CPAP adherent) analyses. Of 285 randomized patients, 90 requiring a full-face mask were excluded, leaving 195 and 151 in the mITT and OT analyses, respectively. Mask acceptance rate was higher in the MFX versus control group (mITT: 79% vs 68%, P = 0.067; OT: 90% vs 76%, P = 0.022). CPAP compliance was higher (5.9 ± 1.8 vs 5.1 ± 1.6 h/night, P = 0.011) and nasal mask issue-related HCP visits lower (3% vs 17%, P = 0.006) in the MFX group. Nasal mask failures due to mask discomfort (5% vs 1%) or unintentional leakage (5% vs 0%) were higher in control vs MFX group. Mask acceptance was significantly associated with fewer mask leaks (P = 0.002) and higher pressure therapy (P = 0.042). This study highlights differences between nasal masks for CPAP delivery and shows that initial mask selection can influence adherence and healthcare utilization during CPAP. © 2016 ResMed Germany Inc. The Clinical Respiratory Journal published by John Wiley & Sons Ltd.

  6. Equivalence of Nasal and Oronasal Masks during Initial CPAP Titration for Obstructive Sleep Apnea Syndrome

    PubMed Central

    Teo, Ming; Amis, Terence; Lee, Sharon; Falland, Karina; Lambert, Stephen; Wheatley, John

    2011-01-01

    Study Objective: Continuous positive airway pressure (CPAP) titration studies are commonly performed using a nasal mask but some patients may prefer a full-face or oronasal mask. There is little evidence regarding the equivalence of different mask interfaces used to initiate treatment. We hypothesized that oronasal breathing when using an oronasal mask increases upper airway collapsibility and that a higher pressure may be required to maintain airway patency. We also assessed patient preferences for the 2 mask interfaces. Design: Prospective, randomized, cross-over design with 2 consecutive CPAP titration nights. Setting: Accredited laboratory in a university hospital. Patients or Participants: Twenty-four treatment-naive subjects with obstructive sleep apnea syndrome and respiratory disturbance index of greater than 15 events per hour. Interventions: CPAP titration was performed using an auto-titrating machine with randomization to a nasal or oronasal mask, followed by a second titration night using the alternate mask style. Measurements and Results: There was no significant difference in the mean pressures determined between nasal and oronasal masks, although 43% of subjects had nasal-to-oronasal mask-pressure differences of 2 cm H2O or more. Residual respiratory events, arousals, and measured leak were all greater with the oronasal mask. Seventy-nine percent of subjects preferred the nasal mask. Conclusions: Patients with obstructive sleep apnea syndrome can generally switch between nasal and oronasal masks without changing machine pressure, although there are individual differences that may be clinically significant. Measured leak is greater with the oronasal mask. Most patients with obstructive sleep apnea syndrome prefer a nasal mask as the interface for initiation of CPAP. Clinical Trial Registration: Australian New Zealand Clinical Trials Registry (ANZCTR). ACTRN: ACTRN12611000243910. URL: http://www.ANZCTR.org.au/ACTRN12611000243910.aspx Citation: Teo M

  7. The Background of Reduced Face Specificity of N170 in Congenital Prosopagnosia

    PubMed Central

    Schweinberger, Stefan R.; Vakli, Pál; Kovács, Gyula

    2014-01-01

    Congenital prosopagnosia is lifelong face-recognition impairment in the absence of evidence for structural brain damage. To study the neural correlates of congenital prosopagnosia, we measured the face-sensitive N170 component of the event-related potential in three members of the same family (father (56 y), son (25 y) and daughter (22 y)) and in age-matched neurotypical participants (young controls: n = 14; 24.5 y±2.1; old controls: n = 6; 57.3 y±5.4). To compare the face sensitivity of N170 in congenital prosopagnosic and neurotypical participants we measured the event-related potentials for faces and phase-scrambled random noise stimuli. In neurotypicals we found significantly larger N170 amplitude for faces compared to noise stimuli, reflecting normal early face processing. The congenital prosopagnosic participants, by contrast, showed reduced face sensitivity of the N170, and this was due to a larger than normal noise-elicited N170, rather than to a smaller face-elicited N170. Interestingly, single-trial analysis revealed that the lack of face sensitivity in congenital prosopagnosia is related to a larger oscillatory power and phase-locking in the theta frequency-band (4–7 Hz, 130–190 ms) as well as to a lower intertrial jitter of the response latency for the noise stimuli. Altogether, these results suggest that congenital prosopagnosia is due to the deficit of early, structural encoding steps of face perception in filtering between face and non-face stimuli. PMID:24983881

  8. Modulation cues influence binaural masking-level difference in masking-pattern experiments.

    PubMed

    Nitschmann, Marc; Verhey, Jesko L

    2012-03-01

    Binaural masking patterns show a steep decrease in the binaural masking-level difference (BMLD) when masker and signal have no frequency component in common. Experimental threshold data are presented together with model simulations for a diotic masker centered at 250 or 500 Hz and a bandwidth of 10 or 100 Hz masking a sinusoid interaurally in phase (S(0)) or in antiphase (S(π)). Simulations with a binaural model, including a modulation filterbank for the monaural analysis, indicate that a large portion of the decrease in the BMLD in remote-masking conditions may be due to an additional modulation cue available for monaural detection. © 2012 Acoustical Society of America

  9. Mask industry assessment: 2008

    NASA Astrophysics Data System (ADS)

    Hughes, Greg; Yun, Henry

    2008-10-01

    Microelectronics industry leaders routinely name the cost and cycle time of mask technology and mask supply as top critical issues. A survey was created with support from SEMATECH and administered by David Powell Consulting to gather information about the mask industry as an objective assessment of its overall condition. The survey is designed with the input of semiconductor company mask technologists, merchant mask suppliers, and industry equipment makers. This year's assessment is the seventh in the current series of annual reports. With ongoing industry support, the report can be used as a baseline to gain perspective on the technical and business status of the mask and microelectronics industries. The report will continue to serve as a valuable reference to identify the strengths and opportunities of the mask industry. The results will be used to guide future investments pertaining to critical path issues. This year's survey is basically the same as the 2005 through 2007 surveys. Questions are grouped into categories: General Business Profile Information, Data Processing, Yields and Yield Loss Mechanisms, Delivery Times, Returns, and Services. Within each category is a multitude of questions that create a detailed profile of both the business and technical status of the critical mask industry.

  10. Mask industry assessment: 2009

    NASA Astrophysics Data System (ADS)

    Hughes, Greg; Yun, Henry

    2009-10-01

    Microelectronics industry leaders routinely name the cost and cycle time of mask technology and mask supply as top critical issues. A survey was created with support from SEMATECH and administered by David Powell Consulting to gather information about the mask industry as an objective assessment of its overall condition. The survey is designed with the input of semiconductor company mask technologists and merchant mask suppliers. This year's assessment is the eighth in the current series of annual reports. With ongoing industry support, the report can be used as a baseline to gain perspective on the technical and business status of the mask and microelectronics industries. The report will continue to serve as a valuable reference to identify the strengths and opportunities of the mask industry. The results will be used to guide future investments pertaining to critical path issues. This year's survey is basically the same as the 2005 through 2008 surveys. Questions are grouped into categories: General Business Profile Information, Data Processing, Yields and Yield Loss Mechanisms, Delivery Times, Returns, and Services. Within each category is a multitude of questions that create a detailed profile of both the business and technical status of the critical mask industry. This in combination with the past surveys represents a comprehensive view of changes in the industry.

  11. Carbon contamination topography analysis of EUV masks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fan, Y.-J.; Yankulin, L.; Thomas, P.

    2010-03-12

    The impact of carbon contamination on extreme ultraviolet (EUV) masks is significant due to throughput loss and potential effects on imaging performance. Current carbon contamination research primarily focuses on the lifetime of the multilayer surfaces, determined by reflectivity loss and reduced throughput in EUV exposure tools. However, contamination on patterned EUV masks can cause additional effects on absorbing features and the printed images, as well as impacting the efficiency of cleaning process. In this work, several different techniques were used to determine possible contamination topography. Lithographic simulations were also performed and the results compared with the experimental data.

  12. Dynamics of normalization underlying masking in human visual cortex.

    PubMed

    Tsai, Jeffrey J; Wade, Alex R; Norcia, Anthony M

    2012-02-22

    Stimulus visibility can be reduced by other stimuli that overlap the same region of visual space, a process known as masking. Here we studied the neural mechanisms of masking in humans using source-imaged steady state visual evoked potentials and frequency-domain analysis over a wide range of relative stimulus strengths of test and mask stimuli. Test and mask stimuli were tagged with distinct temporal frequencies and we quantified spectral response components associated with the individual stimuli (self terms) and responses due to interaction between stimuli (intermodulation terms). In early visual cortex, masking alters the self terms in a manner consistent with a reduction of input contrast. We also identify a novel signature of masking: a robust intermodulation term that peaks when the test and mask stimuli have equal contrast and disappears when they are widely different. We fit all of our data simultaneously with family of a divisive gain control models that differed only in their dynamics. Models with either very short or very long temporal integration constants for the gain pool performed worse than a model with an integration time of ∼30 ms. Finally, the absolute magnitudes of the response were controlled by the ratio of the stimulus contrasts, not their absolute values. This contrast-contrast invariance suggests that many neurons in early visual cortex code relative rather than absolute contrast. Together, these results provide a more complete description of masking within the normalization framework of contrast gain control and suggest that contrast normalization accomplishes multiple functional goals.

  13. Affect of the unconscious: Visually suppressed angry faces modulate our decisions

    PubMed Central

    Pajtas, Petra E.; Mahon, Bradford Z.; Nakayama, Ken; Caramazza, Alfonso

    2016-01-01

    Emotional and affective processing imposes itself over cognitive processes and modulates our perception of the surrounding environment. In two experiments, we addressed the issue of whether nonconscious processing of affect can take place even under deep states of unawareness, such as those induced by interocular suppression techniques, and can elicit an affective response that can influence our understanding of the surrounding environment. In Experiment 1, participants judged the likeability of an unfamiliar item—a Chinese character—that was preceded by a face expressing a particular emotion (either happy or angry). The face was rendered invisible through an interocular suppression technique (continuous flash suppression; CFS). In Experiment 2, backward masking (BM), a less robust masking technique, was used to render the facial expressions invisible. We found that despite equivalent phenomenological suppression of the visual primes under CFS and BM, different patterns of affective processing were obtained with the two masking techniques. Under BM, nonconscious affective priming was obtained for both happy and angry invisible facial expressions. However, under CFS, nonconscious affective priming was obtained only for angry facial expressions. We discuss an interpretation of this dissociation between affective processing and visual masking techniques in terms of distinct routes from the retina to the amygdala. PMID:23224765

  14. Affect of the unconscious: visually suppressed angry faces modulate our decisions.

    PubMed

    Almeida, Jorge; Pajtas, Petra E; Mahon, Bradford Z; Nakayama, Ken; Caramazza, Alfonso

    2013-03-01

    Emotional and affective processing imposes itself over cognitive processes and modulates our perception of the surrounding environment. In two experiments, we addressed the issue of whether nonconscious processing of affect can take place even under deep states of unawareness, such as those induced by interocular suppression techniques, and can elicit an affective response that can influence our understanding of the surrounding environment. In Experiment 1, participants judged the likeability of an unfamiliar item--a Chinese character--that was preceded by a face expressing a particular emotion (either happy or angry). The face was rendered invisible through an interocular suppression technique (continuous flash suppression; CFS). In Experiment 2, backward masking (BM), a less robust masking technique, was used to render the facial expressions invisible. We found that despite equivalent phenomenological suppression of the visual primes under CFS and BM, different patterns of affective processing were obtained with the two masking techniques. Under BM, nonconscious affective priming was obtained for both happy and angry invisible facial expressions. However, under CFS, nonconscious affective priming was obtained only for angry facial expressions. We discuss an interpretation of this dissociation between affective processing and visual masking techniques in terms of distinct routes from the retina to the amygdala.

  15. ERPs reveal subliminal processing of fearful faces.

    PubMed

    Kiss, Monika; Eimer, Martin

    2008-03-01

    To investigate whether facial expression is processed in the absence of conscious awareness, ERPs were recorded in a task in which participants had to identify the expression of masked fearful and neutral target faces. On supraliminal trials (200 ms target duration), in which identification performance was high, a sustained positivity to fearful versus neutral target faces started 140 ms after target face onset. On subliminal trials (8 ms target duration), identification performance was at chance level, but ERPs still showed systematic fear-specific effects. An early positivity to fearful target faces was present but smaller than on supraliminal trials. A subsequent enhanced N2 to fearful faces was only present for subliminal trials. In contrast, a P3 enhancement to fearful faces was observed on supraliminal but not subliminal trials. Results demonstrate rapid emotional expression processing in the absence of awareness.

  16. ERPs reveal subliminal processing of fearful faces

    PubMed Central

    Kiss, Monika; Eimer, Martin

    2008-01-01

    To investigate whether facial expression is processed in the absence of conscious awareness, ERPs were recorded in a task where participants had to identify the expression of masked fearful and neutral target faces. On supraliminal trials (200 ms target duration), where identification performance was high, a sustained positivity to fearful versus neutral target faces started 140 ms after target face onset. On subliminal trials (8 ms target duration), identification performance was at chance level, but ERPs still showed systematic fear-specific effects. An early positivity to fearful target faces was present but smaller than on supraliminal trials. A subsequent enhanced N2 to fearful faces was only present for subliminal trials. In contrast, a P3 enhancement to fearful faces was observed on supraliminal but not subliminal trials. Results demonstrate rapid emotional expression processing in the absence of awareness. PMID:17995905

  17. Set Size and Mask Duration Do Not Interact in Object-Substitution Masking

    ERIC Educational Resources Information Center

    Argyropoulos, Ioannis; Gellatly, Angus; Pilling, Michael; Carter, Wakefield

    2013-01-01

    Object-substitution masking (OSM) occurs when a mask, such as four dots that surround a brief target item, onsets simultaneously with the target and offsets a short time after the target, rather than simultaneously with it. OSM is a reduction in accuracy of reporting the target with the temporally trailing mask, compared with the simultaneously…

  18. Masking as an effective quality control method for next-generation sequencing data analysis.

    PubMed

    Yun, Sajung; Yun, Sijung

    2014-12-13

    Next generation sequencing produces base calls with low quality scores that can affect the accuracy of identifying simple nucleotide variation calls, including single nucleotide polymorphisms and small insertions and deletions. Here we compare the effectiveness of two data preprocessing methods, masking and trimming, and the accuracy of simple nucleotide variation calls on whole-genome sequence data from Caenorhabditis elegans. Masking substitutes low quality base calls with 'N's (undetermined bases), whereas trimming removes low quality bases that results in a shorter read lengths. We demonstrate that masking is more effective than trimming in reducing the false-positive rate in single nucleotide polymorphism (SNP) calling. However, both of the preprocessing methods did not affect the false-negative rate in SNP calling with statistical significance compared to the data analysis without preprocessing. False-positive rate and false-negative rate for small insertions and deletions did not show differences between masking and trimming. We recommend masking over trimming as a more effective preprocessing method for next generation sequencing data analysis since masking reduces the false-positive rate in SNP calling without sacrificing the false-negative rate although trimming is more commonly used currently in the field. The perl script for masking is available at http://code.google.com/p/subn/. The sequencing data used in the study were deposited in the Sequence Read Archive (SRX450968 and SRX451773).

  19. A low cost, simplified, and scaleable pneumotachograph and face mask for neonatal mouse respiratory measurements.

    PubMed

    Sun, Jenny J; Nanu, Roshan; Ray, Russell S

    2017-07-01

    Neonatal respiratory disorders are a leading cause of perinatal mortality due to complications resulting from premature births and prenatal exposure to drugs of abuse, but optimal treatments for these symptoms are still unclear due to a variety of confounds and risk factors. Mouse models present an opportunity to study the underlying mechanisms and efficacy of potential treatments of these conditions with controlled variables. However, measuring respiration in newborn mice is difficult and commercial components are expensive and often require modification, creating a barrier and limiting our understanding of the short and long-term effects of birth complications on respiratory function. Here, we present an inexpensive and simple flow through pneumotachograph and face mask design that can be easily scaled for parallel, high-throughput assays measuring respiration in neonatal mouse pups. The final apparatus consists of three main parts: a water-jacketed chamber, an integrated support tray for the pup, and a pneumotachograph consisting of a two side-arm air channel that is attached to a pressure transducer. The pneumotach showed a linear response and clean, steady respiratory traces in which apneas and sighs were clearly visible. Administration of caffeine in P0.5 CD1 wildtype neonates resulted in an increase in tidal volume, minute ventilation, and minute ventilation normalized to oxygen consumption as well as a decrease in periodic instability. The described methods offer a relatively simple and inexpensive approach to constructing a pneumotachograph for non-invasive measurements of neonatal mouse respiration, enhancing accessibility and enabling the high-throughput and parallel characterizations of neonatal respiratory disorders and potential pharmacological therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. ScAlN etch mask for highly selective silicon etching

    DOE PAGES

    Henry, Michael David; Young, Travis R.; Griffin, Ben

    2017-09-08

    Here, this work reports the utilization of a recently developed film, ScAlN, as a silicon etch mask offering significant improvements in high etch selectivity to silicon. Utilization of ScAlN as a fluorine chemistry based deep reactive ion etch mask demonstrated etch selectivity at 23 550:1, four times better than AlN, 11 times better than Al 2O 3, and 148 times better than silicon dioxide with significantly less resputtering at high bias voltage than either Al 2O 3 or AlN. Ellipsometry film thickness measurements show less than 0.3 nm/min mask erosion rates for ScAlN. Micromasking of resputtered Al for Al 2Omore » 3, AlN, and ScAlN etch masks is also reported here, utilizing cross-sectional scanning electron microscope and confocal microscope roughness measurements. With lower etch bias, the reduced etch rate can be optimized to achieve a trench bottom surface roughness that is comparable to SiO 2 etch masks. Etch mask selectivity enabled by ScAlN is likely to make significant improvements in microelectromechanical systems, wafer level packaging, and plasma dicing of silicon.« less

  1. EUVL mask dual pods to be used for mask shipping and handling in exposure tools

    NASA Astrophysics Data System (ADS)

    Gomei, Yoshio; Ota, Kazuya; Lystad, John; Halbmair, Dave; He, Long

    2007-03-01

    The concept of Extreme Ultra-Violet Lithography (EUVL) mask dual pods is proposed for use in both mask shipping and handling in exposure tools. The inner pod was specially designed to protect masks from particle contamination during shipping from mask houses to wafer factories. It can be installed in a load-lock chamber of exposure tools and evacuated while holding the mask inside. The inner pod upper cover is removed just before the mask is installed to a mask stage. Prototypes were manufactured and tested for shipping and for vacuum cycling. We counted particle adders through these actions with a detectable level of 54 nm and up. The adder count was close to zero, or we can say that the obtained result is within the noise level of our present evaluation environment. This indicates that the present concept is highly feasible for EUVL mask shipping and handling in exposure tools.

  2. Sex Differences in Face Processing: Are Women Less Lateralized and Faster than Men?

    ERIC Educational Resources Information Center

    Godard, Ornella; Fiori, Nicole

    2010-01-01

    The aim of this study was to determine the influence of sex on hemispheric asymmetry and cooperation in a face recognition task. We used a masked priming paradigm in which the prime stimulus was centrally presented; it could be a bisymmetric face or a hemi-face in which facial information was presented in the left or the right visual field and…

  3. Spatial frequency filtered images reveal differences between masked and unmasked processing of emotional information.

    PubMed

    Rohr, Michaela; Wentura, Dirk

    2014-10-01

    High and low spatial frequency information has been shown to contribute differently to the processing of emotional information. In three priming studies using spatial frequency filtered emotional face primes, emotional face targets, and an emotion categorization task, we investigated this issue further. Differences in the pattern of results between short and masked, and short and long unmasked presentation conditions emerged. Given long and unmasked prime presentation, high and low frequency primes triggered emotion-specific priming effects. Given brief and masked prime presentation in Experiment 2, we found a dissociation: High frequency primes caused a valence priming effect, whereas low frequency primes yielded a differentiation between low and high arousing information within the negative domain. Brief and unmasked prime presentation in Experiment 3 revealed that subliminal processing of primes was responsible for the pattern observed in Experiment 2. The implications of these findings for theories of early emotional information processing are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. International Space Station (ISS) Emergency Mask (EM) Development

    NASA Technical Reports Server (NTRS)

    Toon, Katherine P.; Hahn, Jeffrey; Fowler, Michael; Young, Kevin

    2011-01-01

    The Emergency Mask (EM) is considered a secondary response emergency Personal Protective Equipment (PPE) designed to provide respiratory protection to the International Space Station (ISS) crewmembers in response to a post-fire event or ammonia leak. The EM is planned to be delivered to ISS in 2012 to replace the current air purifying respirator (APR) onboard ISS called the Ammonia Respirator (AR). The EM is a one ]size ]fits ]all model designed to fit any size crewmember, unlike the APR on ISS, and uses either two Fire Cartridges (FCs) or two Commercial Off-the-Shelf (COTS) 3M(Trademark). Ammonia Cartridges (ACs) to provide the crew with a minimum of 8 hours of respiratory protection with appropriate cartridge swap ]out. The EM is designed for a single exposure event, for either post ]fire or ammonia, and is a passive device that cannot help crewmembers who cannot breathe on their own. The EM fs primary and only seal is around the wearer fs neck to prevent a crewmember from inhaling contaminants. During the development of the ISS Emergency Mask, several design challenges were faced that focused around manufacturing a leak free mask. The description of those challenges are broadly discussed but focuses on one key design challenge area: bonding EPDM gasket material to Gore(Registered Trademark) fabric hood.

  5. Minimizing the endophthalmitis rate following intravitreal injections using 0.25% povidone-iodine irrigation and surgical mask.

    PubMed

    Shimada, Hiroyuki; Hattori, Takayuki; Mori, Ryusaburo; Nakashizuka, Hiroyuki; Fujita, Kyoko; Yuzawa, Mitsuko

    2013-08-01

    To examine the efficacy of complying with an infection control manual for intravitreal injection of anti-vascular endothelial growth factor (VEGF) preparations in reducing the rate of endophthalmitis. We retrospectively reviewed intravitreal anti-VEGF injections conducted by vitreoretinal specialists at the outpatient injection room of a single university hospital between July 2009 and July 2012. The injections were conducted following an infection control manual established by our department. Doctors and nurses wore surgical masks, and disinfected the patient's eyelid skin with 10% povidone-iodine and then the conjunctiva with 0.25% povidone-iodine. After putting a drape on the patient's face, a lid speculum was placed. The conjunctival surface was again washed with 5 ml of 0.25% povidone-iodine. After waiting at least 30 seconds, intravitreal injection was performed through povidone-iodine. Following injection, the injection site was again washed with 5 ml of 0.25% povidone-iodine. Patients were treated with topical levofloxacin 4 times a day for 3 days before and after the injection. A total of 15,144 injections comprising 548 injections of pegaptanib sodium, 846 injections of bevacizumab, and 13,750 injections of ranibizumab were performed. During this period, no case of suspected or proven infectious endophthalmitis occurred. The endophthalmitis rate was 0 per 15,144 injections, (95% confidence interval, 0.0-0.0%). The results suggest that endophthalmitis can be reduced to a minimum by preventing normal flora of the conjunctiva and bacteria in the oral cavity from entering the vitreous. For this purpose, an infection control manual that requires nurses and doctors to wear surgical mask and drape the patient's face, irrigate the conjunctiva with 0.25% povidone-iodine and wait at least 30 seconds before performing intravitreal injection is useful.

  6. Anesthetic Management by Laryngeal Mask Airway in a Patient With a History of Difficult Intubation Resulting in Dental Injuries

    PubMed Central

    Asahi, Yoshinao; Fujii, Ryosuke; Usui, Naoko; Kagamiuchi, Hajime; Omichi, Shiro; Kotani, Junichiro

    2015-01-01

    Disabled patients may face respiratory problems during general anesthesia because of head and neck anomalies. We describe a case of dental treatment under general anesthesia using a laryngeal mask airway in a disabled patient who faced difficulty in endotracheal intubation on several occasions, 5 of which resulted in dental injuries. PMID:25849470

  7. System for face recognition under expression variations of neutral-sampled individuals using recognized expression warping and a virtual expression-face database

    NASA Astrophysics Data System (ADS)

    Petpairote, Chayanut; Madarasmi, Suthep; Chamnongthai, Kosin

    2018-01-01

    The practical identification of individuals using facial recognition techniques requires the matching of faces with specific expressions to faces from a neutral face database. A method for facial recognition under varied expressions against neutral face samples of individuals via recognition of expression warping and the use of a virtual expression-face database is proposed. In this method, facial expressions are recognized and the input expression faces are classified into facial expression groups. To aid facial recognition, the virtual expression-face database is sorted into average facial-expression shapes and by coarse- and fine-featured facial textures. Wrinkle information is also employed in classification by using a process of masking to adjust input faces to match the expression-face database. We evaluate the performance of the proposed method using the CMU multi-PIE, Cohn-Kanade, and AR expression-face databases, and we find that it provides significantly improved results in terms of face recognition accuracy compared to conventional methods and is acceptable for facial recognition under expression variation.

  8. Management of birth asphyxia in home deliveries in rural Gadchiroli: the effect of two types of birth attendants and of resuscitating with mouth-to-mouth, tube-mask or bag-mask.

    PubMed

    Bang, Abhay T; Bang, Rani A; Baitule, Sanjay B; Reddy, Hanimi M; Deshmukh, Mahesh D

    2005-03-01

    To evaluate the effect of home-based neonatal care on birth asphyxia and to compare the effectiveness of two types of workers and three methods of resuscitation in home delivery. In a field trial of home-based neonatal care in rural Gadchiroli, India, birth asphyxia in home deliveries was managed differently during different phases. Trained traditional birth attendants (TBA) used mouth-to-mouth resuscitation in the baseline years (1993 to 1995). Additional village health workers (VHWs) only observed in 1995 to 1996. In the intervention years (1996 to 2003), they used tube-mask (1996 to 1999) and bag-mask (1999 to 2003). The incidence, case fatality (CF) and asphyxia-specific mortality rate (ASMR) during different phases were compared. During the intervention years, 5033 home deliveries occurred. VHWs were present during 84% home deliveries. The incidence of mild birth asphyxia decreased by 60%, from 14% in the observation year (1995 to 1996) to 6% in the intervention years (p<0.0001). The incidence of severe asphyxia did not change significantly, but the CF in neonates with severe asphyxia decreased by 47.5%, from 39 to 20% (p<0.07) and ASMR by 65%, from 11 to 4% (p<0.02). Mouth-to-mouth resuscitation reduced the ASMR by 12%, tube-mask further reduced the CF by 27% and the ASMR by 67%. The bag-mask showed an additional decrease in CF of 39% and in the fresh stillbirth rate of 33% in comparison to tube-mask (not significant). The cost of bag and mask was US dollars 13 per averted death. Oxytocic injection administered by unqualified doctors showed an odds ratio of three for the occurrence of severe asphyxia or fresh stillbirth. Home-based interventions delivered by a team of TBA and a semiskilled VHW reduced the asphyxia-related neonatal mortality by 65% compared to only TBA. The bag-mask appears to be superior to tube-mask or mouth-to-mouth resuscitation, with an estimated equipment cost of US dollars 13 per death averted.

  9. Masks in Pedagogical Practice

    ERIC Educational Resources Information Center

    Roy, David

    2016-01-01

    In Drama Education mask work is undertaken and presented as both a methodology and knowledge base. There are numerous workshops and journal articles available for teachers that offer knowledge or implementation of mask work. However, empirical examination of the context or potential implementation of masks as a pedagogical tool remains…

  10. Keeping African Masks Real

    ERIC Educational Resources Information Center

    Waddington, Susan

    2012-01-01

    Art is a good place to learn about our multicultural planet, and African masks are prized throughout the world as powerfully expressive artistic images. Unfortunately, multicultural education, especially for young children, can perpetuate stereotypes. Masks taken out of context lose their meaning and the term "African masks" suggests that there is…

  11. Masks in Imaging Flow Cytometry

    PubMed Central

    Dominical, Venina; Samsel, Leigh; McCoy, J. Philip

    2016-01-01

    Data analysis in imaging flow cytometry incorporates elements of flow cytometry together with other aspects of morphological analysis of images. A crucial early step in this analysis is the creation of a mask to distinguish the portion of the image upon which further examination of specified features can be performed. Default masks are provided by the manufacturer of the imaging flow cytometer but additional custom masks can be created by the individual user for specific applications. Flawed or inaccurate masks can have a substantial negative impact on the overall analysis of a sample, thus great care must be taken to ensure the accuracy of masks. Here we discuss various types of masks and cite examples of their use. Furthermore we provide our insight for how to approach selecting and assessing the optimal mask for a specific analysis. PMID:27461256

  12. Subliminal access to abstract face representations does not rely on attention.

    PubMed

    Harry, Bronson; Davis, Chris; Kim, Jeesun

    2012-03-01

    The present study used masked repetition priming to examine whether face representations can be accessed without attention. Two experiments using a face recognition task (fame judgement) presented masked repetition and control primes in spatially unattended locations prior to target onset. Experiment 1 (n=20) used the same images as primes and as targets and Experiment 2 (n=17) used different images of the same individual as primes and targets. Repetition priming was observed across both experiments regardless of whether spatial attention was cued to the location of the prime. Priming occurred for both famous and non-famous targets in Experiment 1 but was only reliable for famous targets in Experiment 2, suggesting that priming in Experiment 1 indexed access to view-specific representations whereas priming in Experiment 2 indexed access to view-invariant, abstract representations. Overall, the results indicate that subliminal access to abstract face representations does not rely on attention. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Effects of non-simultaneous masking on the binaural masking level difference

    PubMed Central

    Buss, Emily; Hall III, Joseph W.

    2011-01-01

    The present study sought to clarify the role of non-simultaneous masking in the binaural masking level difference for maskers that fluctuate in level. In the first experiment the signal was a brief 500-Hz tone, and the masker was a bandpass noise (100–2000 Hz), with the initial and final 200-ms bursts presented at 40-dB spectrum level and the inter-burst gap presented at 20-dB spectrum level. Temporal windows were fitted to thresholds measured for a range of gap durations and signal positions within the gap. In the second experiment, individual differences in out of phase (NoSπ) thresholds were compared for a brief signal in a gapped bandpass masker, a brief signal in a steady bandpass masker, and a long signal in a narrowband (50-Hz-wide) noise masker. The third experiment measured brief tone detection thresholds in forward, simultaneous, and backward masking conditions for a 50- and for a 1900-Hz-wide noise masker centered on the 500-Hz signal frequency. Results are consistent with comparable temporal resolution in the in phase (NoSo) and NoSπ conditions and no effect of temporal resolution on individual observers’ ability to utilize binaural cues in narrowband noise. The large masking release observed for a narrowband noise masker may be due to binaural masking release from non-simultaneous, informational masking. PMID:21361448

  14. Masked areas in shear peak statistics. A forward modeling approach

    DOE PAGES

    Bard, D.; Kratochvil, J. M.; Dawson, W.

    2016-03-09

    The statistics of shear peaks have been shown to provide valuable cosmological information beyond the power spectrum, and will be an important constraint of models of cosmology in forthcoming astronomical surveys. Surveys include masked areas due to bright stars, bad pixels etc., which must be accounted for in producing constraints on cosmology from shear maps. We advocate a forward-modeling approach, where the impacts of masking and other survey artifacts are accounted for in the theoretical prediction of cosmological parameters, rather than correcting survey data to remove them. We use masks based on the Deep Lens Survey, and explore the impactmore » of up to 37% of the survey area being masked on LSST and DES-scale surveys. By reconstructing maps of aperture mass the masking effect is smoothed out, resulting in up to 14% smaller statistical uncertainties compared to simply reducing the survey area by the masked area. We show that, even in the presence of large survey masks, the bias in cosmological parameter estimation produced in the forward-modeling process is ≈1%, dominated by bias caused by limited simulation volume. We also explore how this potential bias scales with survey area and evaluate how much small survey areas are impacted by the differences in cosmological structure in the data and simulated volumes, due to cosmic variance.« less

  15. MASKED AREAS IN SHEAR PEAK STATISTICS: A FORWARD MODELING APPROACH

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bard, D.; Kratochvil, J. M.; Dawson, W., E-mail: djbard@slac.stanford.edu

    2016-03-10

    The statistics of shear peaks have been shown to provide valuable cosmological information beyond the power spectrum, and will be an important constraint of models of cosmology in forthcoming astronomical surveys. Surveys include masked areas due to bright stars, bad pixels etc., which must be accounted for in producing constraints on cosmology from shear maps. We advocate a forward-modeling approach, where the impacts of masking and other survey artifacts are accounted for in the theoretical prediction of cosmological parameters, rather than correcting survey data to remove them. We use masks based on the Deep Lens Survey, and explore the impactmore » of up to 37% of the survey area being masked on LSST and DES-scale surveys. By reconstructing maps of aperture mass the masking effect is smoothed out, resulting in up to 14% smaller statistical uncertainties compared to simply reducing the survey area by the masked area. We show that, even in the presence of large survey masks, the bias in cosmological parameter estimation produced in the forward-modeling process is ≈1%, dominated by bias caused by limited simulation volume. We also explore how this potential bias scales with survey area and evaluate how much small survey areas are impacted by the differences in cosmological structure in the data and simulated volumes, due to cosmic variance.« less

  16. Accurate mask-based spatially regularized correlation filter for visual tracking

    NASA Astrophysics Data System (ADS)

    Gu, Xiaodong; Xu, Xinping

    2017-01-01

    Recently, discriminative correlation filter (DCF)-based trackers have achieved extremely successful results in many competitions and benchmarks. These methods utilize a periodic assumption of the training samples to efficiently learn a classifier. However, this assumption will produce unwanted boundary effects, which severely degrade the tracking performance. Correlation filters with limited boundaries and spatially regularized DCFs were proposed to reduce boundary effects. However, their methods used the fixed mask or predesigned weights function, respectively, which was unsuitable for large appearance variation. We propose an accurate mask-based spatially regularized correlation filter for visual tracking. Our augmented objective can reduce the boundary effect even in large appearance variation. In our algorithm, the masking matrix is converted into the regularized function that acts on the correlation filter in frequency domain, which makes the algorithm fast convergence. Our online tracking algorithm performs favorably against state-of-the-art trackers on OTB-2015 Benchmark in terms of efficiency, accuracy, and robustness.

  17. The mysterious noh mask: contribution of multiple facial parts to the recognition of emotional expressions.

    PubMed

    Miyata, Hiromitsu; Nishimura, Ritsuko; Okanoya, Kazuo; Kawai, Nobuyuki

    2012-01-01

    A Noh mask worn by expert actors when performing on a Japanese traditional Noh drama is suggested to convey countless different facial expressions according to different angles of head/body orientation. The present study addressed the question of how different facial parts of a Noh mask, including the eyebrows, the eyes, and the mouth, may contribute to different emotional expressions. Both experimental situations of active creation and passive recognition of emotional facial expressions were introduced. In Experiment 1, participants either created happy or sad facial expressions, or imitated a face that looked up or down, by actively changing each facial part of a Noh mask image presented on a computer screen. For an upward tilted mask, the eyebrows and the mouth shared common features with sad expressions, whereas the eyes with happy expressions. This contingency tended to be reversed for a downward tilted mask. Experiment 2 further examined which facial parts of a Noh mask are crucial in determining emotional expressions. Participants were exposed to the synthesized Noh mask images with different facial parts expressing different emotions. Results clearly revealed that participants primarily used the shape of the mouth in judging emotions. The facial images having the mouth of an upward/downward tilted Noh mask strongly tended to be evaluated as sad/happy, respectively. The results suggest that Noh masks express chimeric emotional patterns, with different facial parts conveying different emotions This appears consistent with the principles of Noh which highly appreciate subtle and composite emotional expressions, as well as with the mysterious facial expressions observed in Western art. It was further demonstrated that the mouth serves as a diagnostic feature in characterizing the emotional expressions. This indicates the superiority of biologically-driven factors over the traditionally formulated performing styles when evaluating the emotions of the Noh masks.

  18. The Mysterious Noh Mask: Contribution of Multiple Facial Parts to the Recognition of Emotional Expressions

    PubMed Central

    Miyata, Hiromitsu; Nishimura, Ritsuko; Okanoya, Kazuo; Kawai, Nobuyuki

    2012-01-01

    Background A Noh mask worn by expert actors when performing on a Japanese traditional Noh drama is suggested to convey countless different facial expressions according to different angles of head/body orientation. The present study addressed the question of how different facial parts of a Noh mask, including the eyebrows, the eyes, and the mouth, may contribute to different emotional expressions. Both experimental situations of active creation and passive recognition of emotional facial expressions were introduced. Methodology/Principal Findings In Experiment 1, participants either created happy or sad facial expressions, or imitated a face that looked up or down, by actively changing each facial part of a Noh mask image presented on a computer screen. For an upward tilted mask, the eyebrows and the mouth shared common features with sad expressions, whereas the eyes with happy expressions. This contingency tended to be reversed for a downward tilted mask. Experiment 2 further examined which facial parts of a Noh mask are crucial in determining emotional expressions. Participants were exposed to the synthesized Noh mask images with different facial parts expressing different emotions. Results clearly revealed that participants primarily used the shape of the mouth in judging emotions. The facial images having the mouth of an upward/downward tilted Noh mask strongly tended to be evaluated as sad/happy, respectively. Conclusions/Significance The results suggest that Noh masks express chimeric emotional patterns, with different facial parts conveying different emotions This appears consistent with the principles of Noh which highly appreciate subtle and composite emotional expressions, as well as with the mysterious facial expressions observed in Western art. It was further demonstrated that the mouth serves as a diagnostic feature in characterizing the emotional expressions. This indicates the superiority of biologically-driven factors over the traditionally

  19. Application of advanced structure to multi-tone mask for FPD process

    NASA Astrophysics Data System (ADS)

    Song, Jin-Han; Jeong, Jin-Woong; Kim, Kyu-Sik; Jeong, Woo-Gun; Yun, Sang-Pil; Lee, Dong-Heok; Choi, Sang-Soo

    2017-07-01

    In accordance with improvement of FPD technology, masks such as phase shift mask (PSM) and multi-tone mask (MTM) for a particular purpose also have been developed. Above all, the MTM consisted of more than tri-tone transmittance has a substantial advantage which enables to reduce the number of mask demand in FPD fabrication process contrast to normal mask of two-tone transmittance.[1,2] A chromium (Cr)-based MTM (Typically top type) is being widely employed because of convenience of etch process caused by its only Cr-based structure consisted of Cr absorber layer and Cr half-tone layer. However, the top type of Cr-based MTM demands two Cr sputtering processes after each layer etching process and writing process. For this reason, a different material from the Cr-based MTM is required for reduction of mask fabrication time and cost. In this study, we evaluate a MTM which has a structure combined Cr with molybdenum silicide (MoSi) to resolve the issues mentioned above. The MoSi which is demonstrated by integrated circuit (IC) process is a suitable material for MTM evaluation. This structure could realize multi-transmittance in common with the Cr-based MTM. Moreover, it enables to reduce the number of sputtering process. We investigate a optimized structure upon consideration of productivity along with performance such as critical dimension (CD) variation and transmittance range of each structure. The transmittance is targeted at h-line wavelength (405 nm) in the evaluation. Compared with Cr-based MTM, the performances of all Cr-/MoSi-based MTMs are considered.

  20. Masks: The Artist in Me

    ERIC Educational Resources Information Center

    Skophammer, Karen

    2009-01-01

    Whether masks are made from cardboard, papier-mache, metal, wood, leather, fabric, clay or any combination of these materials, they bring out the artist in people. Young children like to wear masks when they play to pretend they were another person or animal. Masks let them fantasize and be creative. The author's students made masks representing…

  1. Forward masking of frequency modulationa

    PubMed Central

    Byrne, Andrew J.; Wojtczak, Magdalena; Viemeister, Neal F.

    2012-01-01

    Forward masking of sinusoidal frequency modulation (FM) was measured with three types of maskers: FM, amplitude modulation (AM), and a masker created by combining the magnitude spectrum of an FM tone with random component phases. For the signal FM rates used (5, 20, and 40 Hz), an FM masker raised detection thresholds in terms of frequency deviation by a factor of about 5 relative to without a masker. The AM masker produced a much smaller effect, suggesting that FM-to-AM conversion did not contribute substantially to the FM forward masking. The modulation depth of an FM masker had a nonmonotonic effect, with maximal masking observed at an intermediate value within the range of possible depths, while the random-phase FM masker produced less masking, arguing against a spectrally-based explanation for FM forward masking. Broad FM-rate selectivity for forward masking was observed for both 4-kHz and 500-Hz carriers. Thresholds measured as a function of the masker-signal delay showed slow recovery from FM forward masking, with residual masking for delays up to 500 ms. The FM forward-masking effect resembles that observed for AM [Wojtczak and Viemeister (2005). J. Acoust. Soc. Am. 188, 3198–3210] and may reflect modulation-rate selective neural adaptation to FM. PMID:23145618

  2. Object Substitution Masking Induced by Illusory Masks: Evidence for Higher Object-Level Locus of Interference

    ERIC Educational Resources Information Center

    Hirose, Nobuyuki; Osaka, Naoyuki

    2009-01-01

    A briefly presented target can be rendered invisible by a lingering sparse mask that does not even touch it. This form of visual backward masking, called object substitution masking, is thought to occur at the object level of processing. However, it remains unclear whether object-level interference alone produces substitution masking because…

  3. Increasing Cognitive Load Reduces Interference from Masked Appetitive and Aversive but Not Neutral Stimuli

    PubMed Central

    Uher, Rudolf; Brooks, Samantha J.; Bartholdy, Savani; Tchanturia, Kate; Campbell, Iain C.

    2014-01-01

    Interactions between cognition and emotion are important for survival, often occurring in the absence of awareness. These interactions have been proposed to involve competition between cognition and emotion for attentional resources. Emotional stimuli have been reported to impair performance on cognitive tasks of low, but not high, load if stimuli are consciously perceived. This study explored whether this load-dependent interference effect occurred in response to subliminal emotional stimuli. Masked emotional (appetitive and aversive), but not neutral, stimuli interfered with performance accuracy but not response time on a cognitive task (n-back) at low (1-back), but not high (2-back) load. These results show that a load-dependent interference effect applies to masked emotional stimuli and that the effect generalises across stimulus categories with high motivational value. This supports models of selective attention that propose that cognition and emotion compete for attentional resources. More specifically, interference from masked emotional stimuli at low load suggests that attention is biased towards salient stimuli, while dissipation of interference under high load involves top-down regulation of attention. Our data also indicate that top-down goal-directed regulation of attention occurs in the absence of awareness and does not require metacognitive monitoring or evaluation of bias over behaviour, i.e., some degree of self-regulation occurs at a non-conscious level. PMID:24709953

  4. PEEP-masks in patients with severe obstructive pulmonary disease: a negative report.

    PubMed

    Christensen, H R; Simonsen, K; Lange, P; Clementsen, P; Kampmann, J P; Viskum, K; Heideby, J; Koch, U

    1990-03-01

    Positive pressure during expiration by face masks applied by the patient has gained wide acceptance in the treatment of chronic bronchitis, but the efficacy is still unproven. The effect of 6 months of treatment with PEEP-masks (positive end-expiratory pressure) was therefore studied in 47 patients with severe irreversible obstructive pulmonary disease (forced expiratory volume in one second (FEV1) about 1 l), and mucus hypersecretion. Patients were double-blindly randomized to at least 45 min daily treatment with PEEP-masks with either 10 or 0 cm water pressure. After 6 months of treatment, no statistical difference was found between the two groups in change of median values (month 6 - month 0) of FEV1, forced vital capacity (FVC), arterial oxygen tension (PaO2), amount of sputum or dyspnoea. Median values of arterial carbon dioxide tension (PaCO2) decreased significantly (0.03 kPa) in the placebo group. Cough intensity and dyspnoea during walking on staircases improved significantly in the placebo group. No difference among groups was found in number of days bedridden, hospitalized, number of exacerbations or antibiotic consumption. We conclude, that the use of PEEP-masks in these patients is without clinical documentation and cannot be recommended.

  5. Challenges and requirements of mask data processing for multi-beam mask writer

    NASA Astrophysics Data System (ADS)

    Choi, Jin; Lee, Dong Hyun; Park, Sinjeung; Lee, SookHyun; Tamamushi, Shuichi; Shin, In Kyun; Jeon, Chan Uk

    2015-07-01

    To overcome the resolution and throughput of current mask writer for advanced lithography technologies, the platform of e-beam writer have been evolved by the developments of hardware and software in writer. Especially, aggressive optical proximity correction (OPC) for unprecedented extension of optical lithography and the needs of low sensitivity resist for high resolution result in the limit of variable shaped beam writer which is widely used for mass production. The multi-beam mask writer is attractive candidate for photomask writing of sub-10nm device because of its high speed and the large degree of freedom which enable high dose and dose modulation for each pixel. However, the higher dose and almost unlimited appetite for dose modulation challenge the mask data processing (MDP) in aspects of extreme data volume and correction method. Here, we discuss the requirements of mask data processing for multi-beam mask writer and presents new challenges of the data format, data flow, and correction method for user and supplier MDP tool.

  6. Contralateral Masking in Bilateral Cochlear Implant Patients: A Model of Medial Olivocochlear Function Loss

    PubMed Central

    Aronoff, Justin M.; Padilla, Monica; Fu, Qian-Jie; Landsberger, David M.

    2015-01-01

    Contralateral masking is the phenomenon where a masker presented to one ear affects the ability to detect a signal in the opposite ear. For normal hearing listeners, contralateral masking results in masking patterns that are both sharper and dramatically smaller in magnitude than ipsilateral masking. The goal of this study was to investigate whether medial olivocochlear (MOC) efferents are needed for the sharpness and relatively small magnitude of the contralateral masking function. To do this, bilateral cochlear implant patients were tested because, by directly stimulating the auditory nerve, cochlear implants circumvent the effects of the MOC efferents. The results indicated that, as with normal hearing listeners, the contralateral masking function was sharper than the ipsilateral masking function. However, although there was a reduction in the magnitude of the contralateral masking function compared to the ipsilateral masking function, it was relatively modest. This is in sharp contrast to the results of normal hearing listeners where the magnitude of the contralateral masking function is greatly reduced. These results suggest that MOC function may not play a large role in the sharpness of the contralateral masking function but may play a considerable role in the magnitude of the contralateral masking function. PMID:25798581

  7. Removal of bone in CT angiography by multiscale matched mask bone elimination.

    PubMed

    Gratama van Andel, H A F; Venema, H W; Streekstra, G J; van Straten, M; Majoie, C B L M; den Heeten, G J; Grimbergen, C A

    2007-10-01

    For clear visualization of vessels in CT angiography (CTA) images of the head and neck using maximum intensity projection (MIP) or volume rendering (VR) bone has to be removed. In the past we presented a fully automatic method to mask the bone [matched mask bone elimination (MMBE)] for this purpose. A drawback is that vessels adjacent to bone may be partly masked as well. We propose a modification, multiscale MMBE, which reduces this problem by using images at two scales: a higher resolution than usual for image processing and a lower resolution to which the processed images are transformed for use in the diagnostic process. A higher in-plane resolution is obtained by the use of a sharper reconstruction kernel. The out-of-plane resolution is improved by deconvolution or by scanning with narrower collimation. The quality of the mask that is used to remove bone is improved by using images at both scales. After masking, the desired resolution for the normal clinical use of the images is obtained by blurring with Gaussian kernels of appropriate widths. Both methods (multiscale and original) were compared in a phantom study and with clinical CTA data sets. With the multiscale approach the width of the strip of soft tissue adjacent to the bone that is masked can be reduced from 1.0 to 0.2 mm without reducing the quality of the bone removal. The clinical examples show that vessels adjacent to bone are less affected and therefore better visible. Images processed with multiscale MMBE have a slightly higher noise level or slightly reduced resolution compared with images processed by the original method and the reconstruction and processing time is also somewhat increased. Nevertheless, multiscale MMBE offers a way to remove bone automatically from CT angiography images without affecting the integrity of the blood vessels. The overall image quality of MIP or VR images is substantially improved relative to images processed with the original MMBE method.

  8. Optical inspection of NGL masks

    NASA Astrophysics Data System (ADS)

    Pettibone, Donald W.; Stokowski, Stanley E.

    2004-12-01

    For the last five years KLA-Tencor and our joint venture partners have pursued a research program studying the ability of optical inspection tools to meet the inspection needs of possible NGL lithographies. The NGL technologies that we have studied include SCALPEL, PREVAIL, EUV lithography, and Step and Flash Imprint Lithography. We will discuss the sensitivity of the inspection tools and mask design factors that affect tool sensitivity. Most of the work has been directed towards EUV mask inspection and how to optimize the mask to facilitate inspection. Our partners have succeeded in making high contrast EUV masks ranging in contrast from 70% to 98%. Die to die and die to database inspection of EUV masks have been achieved with a sensitivity that is comparable to what can be achieved with conventional photomasks, approximately 80nm defect sensitivity. We have inspected SCALPEL masks successfully. We have found a limitation of optical inspection when applied to PREVAIL stencil masks. We have run inspections on SFIL masks in die to die, reflected light, in an effort to provide feedback to improve the masks. We have used a UV inspection system to inspect both unpatterned EUV substrates (no coatings) and blanks (with EUV multilayer coatings). These inspection results have proven useful in driving down the substrate and blank defect levels.

  9. Layperson mouth-to-mask ventilation using a modified I-gel laryngeal mask after brief onsite instruction: a manikin-based feasibility trial.

    PubMed

    Schälte, Gereon; Bomhard, Lilli-Theresa; Rossaint, Rolf; Coburn, Mark; Stoppe, Christian; Zoremba, Norbert; Rieg, Annette

    2016-05-12

    The intention of this manikin-based trial was to evaluate whether laypersons are able to operate an I-gel laryngeal mask (I-gel) modified for mouth-to-mask ventilation after receiving brief on-site instruction. Entrance hall of a university hospital and the city campus of a public technical university, using a protected manikin scenario. Laypersons were handed a labelled, mouthpiece-integrated I-gel laryngeal mask and a corresponding instruction chart and were asked to follow the printed instructions. The overall process was analysed and evaluated according to quality and duration. Data from 100 participants were analysed. Overall, 79% of participants were able to effectively ventilate the manikin, 90% placed the laryngeal mask with the correct turn and direction, 19% did not position the mask deep enough and 85% believed that their inhibition threshold for performing resuscitation was lowered. A significant reduction in reluctance before and after the trial was found (p<0.0001). A total of 35% of participants had concerns about applying first aid in an emergency. Former basic life support (BLS) training significantly reduced the time of insertion (19.6 s, 95% CI 17.8 to 21.5, p=0.0004) and increased overall success (p=0.0096). Laypersons were able to manage mouth-to-mask ventilation in the manikin with a reasonable success rate after receiving brief chart-based on-site instructions using a labelled I-gel mask. Positioning the mask deep enough and identifying whether the manikin was successfully ventilated were the main problems observed. A significant reduction in reluctance towards initialising BLS by using a modified supraglottic airway device (SAD) may lead to better acceptance of bystander resuscitation in laypersons, supporting the introduction of SADs into BLS courses and the stocking of SADs in units with public automatic external defibrillators. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a

  10. Masking Release in Children and Adults With Hearing Loss When Using Amplification

    PubMed Central

    McCreery, Ryan; Kopun, Judy; Lewis, Dawna; Alexander, Joshua; Stelmachowicz, Patricia

    2016-01-01

    Purpose This study compared masking release for adults and children with normal hearing and hearing loss. For the participants with hearing loss, masking release using simulated hearing aid amplification with 2 different compression speeds (slow, fast) was compared. Method Sentence recognition in unmodulated noise was compared with recognition in modulated noise (masking release). Recognition was measured for participants with hearing loss using individualized amplification via the hearing-aid simulator. Results Adults with hearing loss showed greater masking release than the children with hearing loss. Average masking release was small (1 dB) and did not depend on hearing status. Masking release was comparable for slow and fast compression. Conclusions The use of amplification in this study contrasts with previous studies that did not use amplification. The results suggest that when differences in audibility are reduced, participants with hearing loss may be able to take advantage of dips in the noise levels, similar to participants with normal hearing. Although children required a more favorable signal-to-noise ratio than adults for both unmodulated and modulated noise, masking release was not statistically different. However, the ability to detect a difference may have been limited by the small amount of masking release observed. PMID:26540194

  11. Mask Industry Assessment: 2011

    NASA Astrophysics Data System (ADS)

    Chan, Y. David

    2011-11-01

    A survey supported by SEMATECH and administered by David Powell Consulting was sent to microelectronics industry leaders to gather information about the mask industry as an objective assessment of its overall condition. The survey was designed with the input of semiconductor company mask technologists and merchant mask suppliers. This year's assessment is the tenth in the current series of annual reports. With ongoing industry support, the report has been used as one of the baselines to gain perspective on the technical and business status of the mask and microelectronics industries. It continues to serve as a valuable reference to identify the strengths and opportunities of the mask industry. The results will be used to guide future investments pertaining to critical path issues. This year's survey was essentially the same as the 2005 through 2010 surveys. Questions are grouped into following categories: General Business Profile Information, Data Processing, Yields and Yield Loss Mechanisms, Delivery Times, Returns, and Services. Within each category are multiple questions that result in a detailed profile of both the business and technical status of the critical mask industry. This profile combined with the responses to past surveys represents a comprehensive view of changes in the industry.

  12. Mask Industry Assessment: 2010

    NASA Astrophysics Data System (ADS)

    Hughes, Greg; Chan, David Y.

    2010-09-01

    A survey created supported by SEMATECH and administered by David Powell Consulting was sent to microelectronics industry leaders to gather information about the mask industry as an objective assessment of its overall condition. The survey was designed with the input of semiconductor company mask technologists and merchant mask suppliers. This year's assessment is the ninth in the current series of annual reports. With ongoing industry support, the report can be used as a baseline to gain perspective on the technical and business status of the mask and microelectronics industries. It will continue to serve as a valuable reference to identify the strengths and opportunities of the mask industry. The results will be used to guide future investments pertaining to critical path issues. This year's survey was basically the same as the 2005 through 2009 surveys. Questions are grouped into categories: General Business Profile Information, Data Processing, Yields and Yield Loss Mechanisms, Delivery Times, Returns, and Services. Within each category are multiple questions that result in a detailed profile of both the business and technical status of the critical mask industry. This profile combined with the responses to past surveys represents a comprehensive view of changes in the industry.

  13. Face processing in autism: Reduced integration of cross-feature dynamics.

    PubMed

    Shah, Punit; Bird, Geoffrey; Cook, Richard

    2016-02-01

    Characteristic problems with social interaction have prompted considerable interest in the face processing of individuals with Autism Spectrum Disorder (ASD). Studies suggest that reduced integration of information from disparate facial regions likely contributes to difficulties recognizing static faces in this population. Recent work also indicates that observers with ASD have problems using patterns of facial motion to judge identity and gender, and may be less able to derive global motion percepts. These findings raise the possibility that feature integration deficits also impact the perception of moving faces. To test this hypothesis, we examined whether observers with ASD exhibit susceptibility to a new dynamic face illusion, thought to index integration of moving facial features. When typical observers view eye-opening and -closing in the presence of asynchronous mouth-opening and -closing, the concurrent mouth movements induce a strong illusory slowing of the eye transitions. However, we find that observers with ASD are not susceptible to this illusion, suggestive of weaker integration of cross-feature dynamics. Nevertheless, observers with ASD and typical controls were equally able to detect the physical differences between comparison eye transitions. Importantly, this confirms that observers with ASD were able to fixate the eye-region, indicating that the striking group difference has a perceptual, not attentional origin. The clarity of the present results contrasts starkly with the modest effect sizes and equivocal findings seen throughout the literature on static face perception in ASD. We speculate that differences in the perception of facial motion may be a more reliable feature of this condition. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Mask quality assessment

    NASA Astrophysics Data System (ADS)

    Regis, Larry; Paulson, Neil; Reynolds, James A.

    1994-02-01

    Product quality and timely delivery are two of the most important parameters, determining the success of a mask manufacturing facility. Because of the sensitivity of this data, however, very little is known about industry performance in these areas. Using Arthur Andersen & Co. to protect contributor identity, the authors have conducted a blind quality survey of mask shops which represents over 75% of the total merchant and captive mask volume in the US. Quantities such as return rate, plate survival yield, performance to schedule and reason for return were requested from 1988 through Q2 1993. Data is analyzed and conclusions are presented.

  15. Are attractive men's faces masculine or feminine? The importance of controlling confounds in face stimuli.

    PubMed

    DeBruine, Lisa M; Jones, Benedict C; Smith, Finlay G; Little, Anthony C

    2010-06-01

    Women's preferences for male masculinity are highly variable. Although many researchers explain this variability as reflecting systematic individual differences in how women resolve the tradeoff between the costs and benefits of choosing a masculine partner, others suggest that methodological differences between studies are responsible. A recent study found general femininity preferences for judgments of faces that were manipulated in sexual dimorphism of shape but general masculinity preferences for judgments of faces that were based on perceived masculinity. Using the original stimuli, we replicated these previous results but found equivalent general femininity preferences for both types of faces when nonface confounds in the stimuli (e.g. hairstyle) were eliminated through masking. We conclude that care must be taken to control potential confounds in stimuli and that the influence of nonface cues on preferences for facial masculinity deserves further study.

  16. Additivity of nonsimultaneous masking for short Gaussian-shaped sinusoids.

    PubMed

    Laback, Bernhard; Balazs, Peter; Necciari, Thibaud; Savel, Sophie; Ystad, Solvi; Meunier, Sabine; Kronland-Martinet, Richard

    2011-02-01

    The additivity of nonsimultaneous masking was studied using Gaussian-shaped tone pulses (referred to as Gaussians) as masker and target stimuli. Combinations of up to four temporally separated Gaussian maskers with an equivalent rectangular bandwidth of 600 Hz and an equivalent rectangular duration of 1.7 ms were tested. Each masker was level-adjusted to produce approximately 8 dB of masking. Excess masking (exceeding linear additivity) was generally stronger than reported in the literature for longer maskers and comparable target levels. A model incorporating a compressive input/output function, followed by a linear summation stage, underestimated excess masking when using an input/output function derived from literature data for longer maskers and comparable target levels. The data could be predicted with a more compressive input/output function. Stronger compression may be explained by assuming that the Gaussian stimuli were too short to evoke the medial olivocochlear reflex (MOCR), whereas for longer maskers tested previously the MOCR caused reduced compression. Overall, the interpretation of the data suggests strong basilar membrane compression for very short stimuli.

  17. Inexpensive Masks for Film Deposition

    NASA Technical Reports Server (NTRS)

    Conley, W. R.

    1986-01-01

    Sputtered sprayed lines less than 2 millimeters wide made by superimposing masks with partially overlapping openings. Slits first cut in masks by stamping or other economical process. Masks superimposed so slits define new openings narrower than original slits.

  18. Mask industry assessment trend analysis

    NASA Astrophysics Data System (ADS)

    Hughes, Greg; Yun, Henry

    2009-01-01

    Microelectronics industry leaders routinely name the cost and cycle time of mask technology and mask supply as top critical issues. A survey was created with support from SEMATECH to gather information about the mask industry as an objective assessment of its overall condition. This year's survey data were presented in detail at BACUS and the detailed trend analysis presented at EMLC. The survey is designed with the input of semiconductor company mask technologists and merchant mask suppliers. This year's assessment is the seventh in the current series of annual reports. With continued industry support, the report can be used as a baseline to gain perspective on the technical and business status of the mask and microelectronics industries. The report will continue to serve as a valuable reference to identify the strengths and opportunities of the mask industry. The results will be used to guide future investments on critical path issues. This year's survey is basically the same as the surveys in 2005 through 2007. Questions are grouped into seven categories: General Business Profile Information, Data Processing, Yields and Yield Loss, Mechanisms, Delivery Times, Returns, and Services. (Examples are given below). Within each category is a multitude of questions that creates a detailed profile of both the business and technical status of the critical mask industry.

  19. Masking Strategies for Image Manifolds.

    PubMed

    Dadkhahi, Hamid; Duarte, Marco F

    2016-07-07

    We consider the problem of selecting an optimal mask for an image manifold, i.e., choosing a subset of the pixels of the image that preserves the manifold's geometric structure present in the original data. Such masking implements a form of compressive sensing through emerging imaging sensor platforms for which the power expense grows with the number of pixels acquired. Our goal is for the manifold learned from masked images to resemble its full image counterpart as closely as possible. More precisely, we show that one can indeed accurately learn an image manifold without having to consider a large majority of the image pixels. In doing so, we consider two masking methods that preserve the local and global geometric structure of the manifold, respectively. In each case, the process of finding the optimal masking pattern can be cast as a binary integer program, which is computationally expensive but can be approximated by a fast greedy algorithm. Numerical experiments show that the relevant manifold structure is preserved through the datadependent masking process, even for modest mask sizes.

  20. Etch bias inversion during EUV mask ARC etch

    NASA Astrophysics Data System (ADS)

    Lajn, Alexander; Rolff, Haiko; Wistrom, Richard

    2017-07-01

    The introduction of EUV lithography to high volume manufacturing is now within reach for 7nm technology node and beyond (1), at least for some steps. The scheduling is in transition from long to mid-term. Thus, all contributors need to focus their efforts on the production requirements. For the photo mask industry, these requirements include the control of defectivity, CD performance and lifetime of their masks. The mask CD performance including CD uniformity, CD targeting, and CD linearity/ resolution, is predominantly determined by the photo resist performance and by the litho and etch processes. State-of-the-art chemically amplified resists exhibit an asymmetric resolution for directly and indirectly written features, which usually results in a similarly asymmetric resolution performance on the mask. This resolution gap may reach as high as multiple tens of nanometers on the mask level in dependence of the chosen processes. Depending on the printing requirements of the wafer process, a reduction or even an increase of this gap may be required. A potential way of tuning via the etch process, is to control the lateral CD contribution during etch. Aside from process tuning knobs like pressure, RF powers and gases, which usually also affect CD linearity and CD uniformity, the simplest knob is the etch time itself. An increased over etch time results in an increased CD contribution in the normal case. , We found that the etch CD contribution of ARC layer etch on EUV photo masks is reduced by longer over etch times. Moreover, this effect can be demonstrated to be present for different etch chambers and photo resists.

  1. EUVL Mask Blank Repair

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barty, A; Mirkarimi, P; Stearns, D G

    2002-05-22

    EUV mask blanks are fabricated by depositing a reflective Mo/Si multilayer film onto super-polished substrates. Small defects in this thin film coating can significantly alter the reflected field and introduce defects in the printed image. Ideally one would want to produce defect-free mask blanks; however, this may be very difficult to achieve in practice. One practical way to increase the yield of mask blanks is to effectively repair multilayer defects, and to this effect they present two complementary defect repair strategies for use on multilayer-coated EUVL mask blanks. A defect is any area on the mask which causes unwanted variationsmore » in EUV dose in the aerial image obtained in a printing tool, and defect repair is correspondingly defined as any strategy that renders a defect unprintable during exposure. The term defect mitigation can be adopted to describe any strategy which renders a critical defect non-critical when printed, and in this regard a non-critical defect is one that does not adversely affect device function. Defects in the patterned absorber layer consist of regions where metal, typically chrome, is unintentionally added or removed from the pattern leading to errors in the reflected field. There currently exists a mature technology based on ion beam milling and ion beam assisted deposition for repairing defects in the absorber layer of transmission lithography masks, and it is reasonable to expect that this technology will be extended to the repair of absorber defects in EUVL masks. However, techniques designed for the repair of absorber layers can not be directly applied to the repair of defects in the mask blank, and in particular the multilayer film. In this paper they present for the first time a new technique for the repair of amplitude defects as well as recent results on the repair of phase defects.« less

  2. SEMATECH EUVL mask program status

    NASA Astrophysics Data System (ADS)

    Yun, Henry; Goodwin, Frank; Huh, Sungmin; Orvek, Kevin; Cha, Brian; Rastegar, Abbas; Kearney, Patrick

    2009-04-01

    As we approach the 22nm half-pitch (hp) technology node, the industry is rapidly running out of patterning options. Of the several lithography techniques highlighted in the International Technology Roadmap for Semiconductors (ITRS), the leading contender for the 22nm hp insertion is extreme ultraviolet lithography (EUVL). Despite recent advances with EUV resist and improvements in source power, achieving defect free EUV mask blank and enabling the EUV mask infrastructure still remain critical issues. To meet the desired EUV high volume manufacturing (HVM) insertion target date of 2013, these obstacles must be resolved on a timely bases. Many of the EUV mask related challenges remain in the pre-competitive stage and a collaborative industry based consortia, such as SEMATECH can play an important role to enable the EUVL landscape. SEMATECH based in Albany, NY is an international consortium representing several of the largest manufacturers in the semiconductor market. Full members include Intel, Samsung, AMD, IBM, Panasonic, HP, TI, UMC, CNSE (College of Nanoscience and Engineering), and Fuller Road Management. Within the SEMATECH lithography division a major thrust is centered on enabling the EUVL ecosystem from mask development, EUV resist development and addressing EUV manufacturability concerns. An important area of focus for the SEMATECH mask program has been the Mask Blank Development Center (MBDC). At the MBDC key issues in EUV blank development such as defect reduction and inspection capabilities are actively pursued together with research partners, key suppliers and member companies. In addition the mask program continues a successful track record of working with the mask community to manage and fund critical mask tools programs. This paper will highlight recent status of mask projects and longer term strategic direction at the MBDC. It is important that mask technology be ready to support pilot line development HVM by 2013. In several areas progress has been

  3. Nanoimprint wafer and mask tool progress and status for high volume semiconductor manufacturing

    NASA Astrophysics Data System (ADS)

    Matsuoka, Yoichi; Seki, Junichi; Nakayama, Takahiro; Nakagawa, Kazuki; Azuma, Hisanobu; Yamamoto, Kiyohito; Sato, Chiaki; Sakai, Fumio; Takabayashi, Yukio; Aghili, Ali; Mizuno, Makoto; Choi, Jin; Jones, Chris E.

    2016-10-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash* Imprint Lithography (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed, leaving a patterned resist on the substrate. There are many criteria that determine whether a particular technology is ready for wafer manufacturing. Defectivity and mask life play a significant role relative to meeting the cost of ownership (CoO) requirements in the production of semiconductor devices. Hard particles on a wafer or mask create the possibility of inducing a permanent defect on the mask that can impact device yield and mask life. By using material methods to reduce particle shedding and by introducing an air curtain system, the lifetime of both the master mask and the replica mask can be extended. In this work, we report results that demonstrate a path towards achieving mask lifetimes of better than 1000 wafers. On the mask side, a new replication tool, the FPA-1100 NR2 is introduced. Mask replication is required for nanoimprint lithography (NIL), and criteria that are crucial to the success of a replication platform include both particle control, resolution and image placement accuracy. In this paper we discuss the progress made in both feature resolution and in meeting the image placement specification for replica masks.

  4. Mask_explorer: A tool for exploring brain masks in fMRI group analysis.

    PubMed

    Gajdoš, Martin; Mikl, Michal; Mareček, Radek

    2016-10-01

    Functional magnetic resonance imaging (fMRI) studies of the human brain are appearing in increasing numbers, providing interesting information about this complex system. Unique information about healthy and diseased brains is inferred using many types of experiments and analyses. In order to obtain reliable information, it is necessary to conduct consistent experiments with large samples of subjects and to involve statistical methods to confirm or reject any tested hypotheses. Group analysis is performed for all voxels within a group mask, i.e. a common space where all of the involved subjects contribute information. To our knowledge, a user-friendly interface with the ability to visualize subject-specific details in a common analysis space did not yet exist. The purpose of our work is to develop and present such interface. Several pitfalls have to be avoided while preparing fMRI data for group analysis. One such pitfall is spurious non-detection, caused by inferring conclusions in the volume of a group mask that has been corrupted due to a preprocessing failure. We describe a MATLAB toolbox, called the mask_explorer, designed for prevention of this pitfall. The mask_explorer uses a graphical user interface, enables a user-friendly exploration of subject masks and is freely available. It is able to compute subject masks from raw data and create lists of subjects with potentially problematic data. It runs under MATLAB with the widely used SPM toolbox. Moreover, we present several practical examples where the mask_explorer is usefully applied. The mask_explorer is designed to quickly control the quality of the group fMRI analysis volume and to identify specific failures related to preprocessing steps and acquisition. It helps researchers detect subjects with potentially problematic data and consequently enables inspection of the data. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Auditory Time-Frequency Masking for Spectrally and Temporally Maximally-Compact Stimuli.

    PubMed

    Necciari, Thibaud; Laback, Bernhard; Savel, Sophie; Ystad, Sølvi; Balazs, Peter; Meunier, Sabine; Kronland-Martinet, Richard

    2016-01-01

    Many audio applications perform perception-based time-frequency (TF) analysis by decomposing sounds into a set of functions with good TF localization (i.e. with a small essential support in the TF domain) using TF transforms and applying psychoacoustic models of auditory masking to the transform coefficients. To accurately predict masking interactions between coefficients, the TF properties of the model should match those of the transform. This involves having masking data for stimuli with good TF localization. However, little is known about TF masking for mathematically well-localized signals. Most existing masking studies used stimuli that are broad in time and/or frequency and few studies involved TF conditions. Consequently, the present study had two goals. The first was to collect TF masking data for well-localized stimuli in humans. Masker and target were 10-ms Gaussian-shaped sinusoids with a bandwidth of approximately one critical band. The overall pattern of results is qualitatively similar to existing data for long maskers. To facilitate implementation in audio processing algorithms, a dataset provides the measured TF masking function. The second goal was to assess the potential effect of auditory efferents on TF masking using a modeling approach. The temporal window model of masking was used to predict present and existing data in two configurations: (1) with standard model parameters (i.e. without efferents), (2) with cochlear gain reduction to simulate the activation of efferents. The ability of the model to predict the present data was quite good with the standard configuration but highly degraded with gain reduction. Conversely, the ability of the model to predict existing data for long maskers was better with than without gain reduction. Overall, the model predictions suggest that TF masking can be affected by efferent (or other) effects that reduce cochlear gain. Such effects were avoided in the experiment of this study by using maximally

  6. Mask pattern generator employing EPL technology

    NASA Astrophysics Data System (ADS)

    Yoshioka, Nobuyuki; Yamabe, Masaki; Wakamiya, Wataru; Endo, Nobuhiro

    2003-08-01

    Mask cost is one of crucial issues in device fabrication, especially in SoC (System on a Chip) with small-volume production. The cost mainly depends on productivity of mask manufacturing tools such as mask writers and defect inspection tools. EPL (Electron Projection Lithography) has been developing as a high-throughput electron beam exposure technology that will succeed optical lithography. The application of EPL technology to mask writing will result in high productivity and contribute to decrease the mask cost. The concept of a mask pattern generator employing EPL technology is proposed in this paper. It is very similar to EPL technology used for pattern printing on a wafer. The mask patterns on the glass substrate are exposed by projecting the basic circuit patterns formed on the mother EPL mask. One example of the mother EPL mask is a stencil type made with 200-mm Si wafer. The basic circuit patterns are IP patterns and logical primitive patterns such as cell libraries (AND, OR, Inverter, Flip-Flop and etc.) to express the SoC device patterns. Since the SoC patterns are exposed with its collective units such as IP and logical primitive patterns by using this method, the high throughput will be expected comparing with conventional mask E-beam writers. In this paper, the mask pattern generator with the EPL technology is proposed. The concept, its advantages and issues to be solved are discussed.

  7. Visual Masking During Pursuit Eye Movements

    ERIC Educational Resources Information Center

    White, Charles W.

    1976-01-01

    Visual masking occurs when one stimulus interferes with the perception of another stimulus. Investigates which matters more for visual masking--that the target and masking stimuli are flashed on the same part of the retina, or, that the target and mask appear in the same place. (Author/RK)

  8. EUV mask defect inspection and defect review strategies for EUV pilot line and high volume manufacturing

    NASA Astrophysics Data System (ADS)

    Chan, Y. David; Rastegar, Abbas; Yun, Henry; Putna, E. Steve; Wurm, Stefan

    2010-04-01

    Reducing mask blank and patterned mask defects is the number one challenge for extreme ultraviolet lithography. If the industry succeeds in reducing mask blank defects at the required rate of 10X every year for the next 2-3 years to meet high volume manufacturing defect requirements, new inspection and review tool capabilities will soon be needed to support this goal. This paper outlines the defect inspection and review tool technical requirements and suggests development plans to achieve pilot line readiness in 2011/12 and high volume manufacturing readiness in 2013. The technical specifications, tooling scenarios, and development plans were produced by a SEMATECH-led technical working group with broad industry participation from material suppliers, tool suppliers, mask houses, integrated device manufacturers, and consortia. The paper summarizes this technical working group's assessment of existing blank and mask inspection/review infrastructure capabilities to support pilot line introduction and outlines infrastructure development requirements and tooling strategies to support high volume manufacturing.

  9. Oronasal Masks Require a Higher Pressure than Nasal and Nasal Pillow Masks for the Treatment of Obstructive Sleep Apnea

    PubMed Central

    Deshpande, Sheetal; Joosten, Simon; Turton, Anthony; Edwards, Bradley A.; Landry, Shane; Mansfield, Darren R.; Hamilton, Garun S.

    2016-01-01

    Study Objectives: Oronasal masks are frequently used for continuous positive airway pressure (CPAP) treatment in patients with obstructive sleep apnea (OSA). The aim of this study was to (1) determine if CPAP requirements are higher for oronasal masks compared to nasal mask interfaces and (2) assess whether polysomnography and patient characteristics differed among mask preference groups. Methods: Retrospective analysis of all CPAP implementation polysomnograms between July 2013 and June 2014. Prescribed CPAP level, polysomnography results and patient data were compared according to mask type (n = 358). Results: Oronasal masks were used in 46%, nasal masks in 35% and nasal pillow masks in 19%. There was no difference according to mask type for baseline apnea-hypopnea index (AHI), body mass index (BMI), waist or neck circumference. CPAP level was higher for oronasal masks, 12 (10–15.5) cm H2O compared to nasal pillow masks, 11 (8–12.5) cm H2O and nasal masks, 10 (8–12) cm H2O, p < 0.0001 (Median [interquartile range]). Oronasal mask type, AHI, age, and BMI were independent predictors of a higher CPAP pressure (p < 0.0005, adjusted R2 = 0.26.). For patients with CPAP ≥ 15 cm H2O, there was an odds ratio of 4.5 (95% CI 2.5–8.0) for having an oronasal compared to a nasal or nasal pillow mask. Residual median AHI was higher for oronasal masks (11.3 events/h) than for nasal masks (6.4 events/h) and nasal pillows (6.7 events/h), p < 0.001. Conclusions: Compared to nasal mask types, oronasal masks are associated with higher CPAP pressures (particularly pressures ≥ 15 cm H2O) and a higher residual AHI. Further evaluation with a randomized control trial is required to definitively establish the effect of mask type on pressure requirements. Commentary: A commentary on this article appears in this issue on page 1209. Citation: Deshpande S, Joosten S, Turton A, Edwards BA, Landry S, Mansfield DR, Hamilton GS. Oronasal masks require a higher pressure than nasal and

  10. Oronasal Masks Require a Higher Pressure than Nasal and Nasal Pillow Masks for the Treatment of Obstructive Sleep Apnea.

    PubMed

    Deshpande, Sheetal; Joosten, Simon; Turton, Anthony; Edwards, Bradley A; Landry, Shane; Mansfield, Darren R; Hamilton, Garun S

    2016-09-15

    Oronasal masks are frequently used for continuous positive airway pressure (CPAP) treatment in patients with obstructive sleep apnea (OSA). The aim of this study was to (1) determine if CPAP requirements are higher for oronasal masks compared to nasal mask interfaces and (2) assess whether polysomnography and patient characteristics differed among mask preference groups. Retrospective analysis of all CPAP implementation polysomnograms between July 2013 and June 2014. Prescribed CPAP level, polysomnography results and patient data were compared according to mask type (n = 358). Oronasal masks were used in 46%, nasal masks in 35% and nasal pillow masks in 19%. There was no difference according to mask type for baseline apnea-hypopnea index (AHI), body mass index (BMI), waist or neck circumference. CPAP level was higher for oronasal masks, 12 (10-15.5) cm H2O compared to nasal pillow masks, 11 (8-12.5) cm H2O and nasal masks, 10 (8-12) cm H2O, p < 0.0001 (Median [interquartile range]). Oronasal mask type, AHI, age, and BMI were independent predictors of a higher CPAP pressure (p < 0.0005, adjusted R(2) = 0.26.). For patients with CPAP ≥ 15 cm H2O, there was an odds ratio of 4.5 (95% CI 2.5-8.0) for having an oronasal compared to a nasal or nasal pillow mask. Residual median AHI was higher for oronasal masks (11.3 events/h) than for nasal masks (6.4 events/h) and nasal pillows (6.7 events/h), p < 0.001. Compared to nasal mask types, oronasal masks are associated with higher CPAP pressures (particularly pressures ≥ 15 cm H2O) and a higher residual AHI. Further evaluation with a randomized control trial is required to definitively establish the effect of mask type on pressure requirements. A commentary on this article appears in this issue on page 1209. © 2016 American Academy of Sleep Medicine.

  11. How Well Do Computer-Generated Faces Tap Face Expertise?

    PubMed

    Crookes, Kate; Ewing, Louise; Gildenhuys, Ju-Dith; Kloth, Nadine; Hayward, William G; Oxner, Matt; Pond, Stephen; Rhodes, Gillian

    2015-01-01

    The use of computer-generated (CG) stimuli in face processing research is proliferating due to the ease with which faces can be generated, standardised and manipulated. However there has been surprisingly little research into whether CG faces are processed in the same way as photographs of real faces. The present study assessed how well CG faces tap face identity expertise by investigating whether two indicators of face expertise are reduced for CG faces when compared to face photographs. These indicators were accuracy for identification of own-race faces and the other-race effect (ORE)-the well-established finding that own-race faces are recognised more accurately than other-race faces. In Experiment 1 Caucasian and Asian participants completed a recognition memory task for own- and other-race real and CG faces. Overall accuracy for own-race faces was dramatically reduced for CG compared to real faces and the ORE was significantly and substantially attenuated for CG faces. Experiment 2 investigated perceptual discrimination for own- and other-race real and CG faces with Caucasian and Asian participants. Here again, accuracy for own-race faces was significantly reduced for CG compared to real faces. However the ORE was not affected by format. Together these results signal that CG faces of the type tested here do not fully tap face expertise. Technological advancement may, in the future, produce CG faces that are equivalent to real photographs. Until then caution is advised when interpreting results obtained using CG faces.

  12. Temporal Intraspeech Masking of Plosive Bursts: Effects of Hearing Loss and Frequency Shaping

    ERIC Educational Resources Information Center

    Mackersie, Carol L.

    2007-01-01

    Purpose: The purposes were (a) to compare masking of consonant bursts by adjacent vowels for listeners with and without hearing loss and (b) to determine the extent to which the temporal intraspeech masking can be reduced by a simulated hearing-aid frequency-response shaping. Method: Fourteen adults with sensorineural hearing loss and 10 with…

  13. The Relationship between MOC Reflex and Masked Threshold

    PubMed Central

    Garinis, Angela; Werner, Lynne; Abdala, Carolina

    2011-01-01

    Otoacoustic emission (OAE) amplitude can be reduced by acoustic stimulation. This effect is produced by the medial olivocochlear (MOC) reflex. Past studies have shown that the MOC reflex is related to listening in noise and attention. In the present study, the relationship between strength of the contralateral MOC reflex and masked threshold was investigated in 19 adults. Detection thresholds were determined for a 1000-Hz, 300-ms tone presented simultaneously with one repetition of a 300-ms masker in an ongoing train of 300-ms masker bursts at 600-ms intervals. Three masking conditions were tested: 1) broadband noise 2) a fixed-frequency 4-tone complex masker and 3) a random-frequency 4-tone complex masker. Broadband noise was expected to produce energetic masking and the tonal maskers were expected to produce informational masking in some listeners. DPOAEs were recorded at fine frequency interval from 500 to 4000 Hz, with and without contralateral acoustic stimulation. MOC reflex strength was estimated as a reduction in baseline level and a shift in frequency of DPOAE fine-structure maxima near 1000-Hz. MOC reflex and psychophysical testing were completed in separate sessions. Individuals with poorer thresholds in broadband noise and in random-frequency maskers were found to have stronger MOC reflexes. PMID:21878379

  14. Neuroimaging somatosensory perception and masking.

    PubMed

    Meador, Kimford J; Revill, Kathleen Pirog; Epstein, Charles M; Sathian, K; Loring, David W; Rorden, Chris

    2017-01-08

    The specific cortical and subcortical regions involved in conscious perception and masking are uncertain. This study sought to identify brain areas involved in conscious perception of somatosensory stimuli during a masking task using functional magnetic resonance (fMRI) to contrast perceived vs. non-perceived targets. Electrical trains were delivered to the right index finger for targets and to the left index finger for masks. Target intensities were adjusted to compensate for threshold drift. Sham target trials were given in ~10% of the trials, and target stimuli without masks were delivered in one of the five runs (68 trials/run). When healthy dextral adult volunteers (n=15) perceived right hand targets, greater left- than right-cerebral activations were seen with similar patterns across the parietal cortex, thalamus, insula, claustrum, and midbrain. When targets were not perceived, left/right cerebral activations were similar overall. Directly comparing perceived vs. non-perceived stimuli with similar intensities in the masking task revealed predominate activations contralateral to masks. In contrast, activations were greater contralateral to perceived targets if no masks were given or if masks were given but target stimulus intensities were greater for perceived than non-perceived targets. The novel aspects of this study include: 1) imaging of cortical and subcortical activations in healthy humans related to somatosensory perception during a masking task, 2) activations in the human thalamus and midbrain related to perception of stimuli compared to matched non-perceived stimuli, and 3) similar left/right cerebral activation patterns across cortical, thalamic and midbrain structures suggesting interactions across all three levels during conscious perception in humans. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Direct Mask Overlay Inspection

    NASA Astrophysics Data System (ADS)

    Hsia, Liang-Choo; Su, Lo-Soun

    1983-11-01

    In this paper, we present a mask inspection methodology and procedure that involves direct X-Y measurements. A group of dice is selected for overlay measurement; four measurement targets were laid out in the kerf of each die. The measured coordinates are then fit-ted to either a "historical" grid, which reflects the individual tool bias, or to an ideal grid squares fashion. Measurements are done using a Nikon X-Y laser interferometric measurement system, which provides a reference grid. The stability of the measurement system is essential. We then apply appropriate statistics to the residual after the fit to determine the overlay performance. Statistical methods play an important role in the product disposition. The acceptance criterion is, however, a compromise between the cost for mask making and the final device yield. In order to satisfy the demand on mask houses for quality of masks and high volume, mixing lithographic tools in mask making has become more popular, in particular, mixing optical and E-beam tools. In this paper, we also discuss the inspection procedure for mixing different lithographic tools.

  16. Is cognitive behavioural therapy effective in reducing suicidal ideation and behaviour when delivered face-to-face or via e-health? A systematic review and meta-analysis.

    PubMed

    Leavey, Katie; Hawkins, Russell

    2017-09-01

    Cognitive Behavioural Therapy (CBT) is a widely used psychotherapeutic intervention for suicide prevention despite its efficacy for suicide prevention in adults remaining ambiguous. Reluctance or inability to access face-to-face help suggests that e-health delivery may be a valuable resource for suicidal people. The aim of this study was to systematically review and conduct meta-analysis on research assessing the efficacy of CBT delivered via face-to-face and e-health for suicidal ideation and behaviour. A comprehensive literature search of MEDLINE, PsycINFO, Scopus, PubMed and The Cochrane Central Register of Controlled Trials was conducted. From 764 identified articles, 26 met the inclusion criteria for investigating CBT for suicidal ideation and behaviours in adult populations. Data were extracted on study characteristics and meta-analysis was performed where possible. There was a statistically significant, small to medium effect for face-to-face delivered CBT in reducing suicidal ideation and behaviour although there was significant heterogeneity between the included studies. CBT delivered via e-health was not found to be efficacious for reducing suicidal ideation and behaviour in adults though the number of studies reviewed was small.

  17. Coded mask telescopes for X-ray astronomy

    NASA Astrophysics Data System (ADS)

    Skinner, G. K.; Ponman, T. J.

    1987-04-01

    The principle of the coded mask techniques are discussed together with the methods of image reconstruction. The coded mask telescopes built at the University of Birmingham, including the SL 1501 coded mask X-ray telescope flown on the Skylark rocket and the Coded Mask Imaging Spectrometer (COMIS) projected for the Soviet space station Mir, are described. A diagram of a coded mask telescope and some designs for coded masks are included.

  18. Central masking with bilateral cochlear implants

    PubMed Central

    Lin, Payton; Lu, Thomas; Zeng, Fan-Gang

    2013-01-01

    Across bilateral cochlear implants, contralateral threshold shift has been investigated as a function of electrode difference between the masking and probe electrodes. For contralateral electric masking, maximum threshold elevations occurred when the position of the masker and probe electrode was approximately place-matched across ears. The amount of masking diminished with increasing masker-probe electrode separation. Place-dependent masking occurred in both sequentially implanted ears, and was not affected by the masker intensity or the time delay from the masker onset. When compared to previous contralateral masking results in normal hearing, the similarities between place-dependent central masking patterns suggest comparable mechanisms of overlapping excitation in the central auditory nervous system. PMID:23363113

  19. The contribution of forward masking to saccadic inhibition of return.

    PubMed

    Souto, David; Born, Sabine; Kerzel, Dirk

    2018-03-08

    Inhibition of return is the name typically given to the prolonged latency of motor responses directed to a previously cued target location. There is intense debate about the origins of this effect and its function, but most take for granted (despite lack of evidence) that it depends little on forward masking. Therefore, we re-examined the role of forward masking in inhibition of return. Forward masking was indexed by slower saccadic reaction times (SRTs) when the target orientation repeated the cue orientation at the same location. We confirmed effects of orientation repetition in the absence of an attentional bias when cues were presented on both sides of fixation (bilateral presentation). The effect of orientation repetition was reduced with high target contrast, consistent with a low-level origin such as contrast gain control in early visual areas. When presenting cues on only one side of fixation (unilateral presentation), we obtained inhibition of return with longer cue-target intervals and facilitation with targets presented shortly after the cue. The effect of orientation repetition was reduced when facilitation was observed, but was as strong as with bilateral cues when inhibition of return was observed. Therefore, forward masking may contribute to the inhibition of return effect by delaying reaction times to repeated features at the same location, but is not a principal cause of inhibition of return; in agreement with previous views. The saccadic inhibition of return effect is a reaction-time cost when responding to a pre-cued location. Additional object updating costs are typically invoked to explain reaction-time costs observed when cue and target have the same shape. Yet, lower-level, forward masking of the target by the cue can not be ruled out. Importantly, we show an effect of orientation repetition that is consistent with low-level forward masking rather than object updating costs and that does not interact with inhibition of return.

  20. The influence of facial masking and sex on older adults' impressions of individuals with Parkinson's disease.

    PubMed

    Hemmesch, Amanda R; Tickle-Degnen, Linda; Zebrowitz, Leslie A

    2009-09-01

    Parkinson's disease (PD) involves facial masking, which may impair social interaction. Older adult observers who viewed segments of videotaped interviews of individuals with PD expressed less interest in relationships with women with higher masking and judged them as less supportive. Masking did not affect ratings of men in these domains, possibly because higher masking violates gender norms for expressivity in women but not in men. Observers formed less accurate ratings of the social supportiveness and social strain of women than men, and higher masking decreased accuracy for ratings of strain. Results suggest that some of the problems with social relationships in PD may be due to inaccurate impressions and reduced desire to interact with individuals with higher masking, especially women. (c) 2009 APA, all rights reserved.

  1. History and future of mask making

    NASA Astrophysics Data System (ADS)

    Levy, Ken L.

    1996-12-01

    The history of the mask industry has three main periods, which I call the Classical Period, the Dark Ages, and the Renaissance, by analogy with those periods in the history of Western Europe. During the Classical Period, people developed 1X masks and the technology to make them. In the Dark Ages, people exploited the equipment developed during the Classical Period to make 5X reduction reticle, ending the nobility of mask making. In today's Renaissance of mask making, a proliferation of mask types is requiring a rebirth of innovation and creativity. The Renaissance resembles the Classical Period: masks are once again strategic, and technological capability is once again the driver. Meanwhile, the mask industry is carrying forward the productivity and efficiency gains it achieved during the Dark Ages. We must create a new business and economic model to support these changes in the characteristics of the marketplace.

  2. Methods for rapidly processing angular masks of next-generation galaxy surveys

    NASA Astrophysics Data System (ADS)

    Swanson, M. E. C.; Tegmark, Max; Hamilton, Andrew J. S.; Hill, J. Colin

    2008-07-01

    As galaxy surveys become larger and more complex, keeping track of the completeness, magnitude limit and other survey parameters as a function of direction on the sky becomes an increasingly challenging computational task. For example, typical angular masks of the Sloan Digital Sky Survey contain about N = 300000 distinct spherical polygons. Managing masks with such large numbers of polygons becomes intractably slow, particularly for tasks that run in time with a naive algorithm, such as finding which polygons overlap each other. Here we present a `divide-and-conquer' solution to this challenge: we first split the angular mask into pre-defined regions called `pixels', such that each polygon is in only one pixel, and then perform further computations, such as checking for overlap, on the polygons within each pixel separately. This reduces tasks to , and also reduces the important task of determining in which polygon(s) a point on the sky lies from to , resulting in significant computational speedup. Additionally, we present a method to efficiently convert any angular mask to and from the popular HEALPIX format. This method can be generically applied to convert to and from any desired spherical pixelization. We have implemented these techniques in a new version of the MANGLE software package, which is freely available at http://space.mit.edu/home/tegmark/mangle/, along with complete documentation and example applications. These new methods should prove quite useful to the astronomical community, and since MANGLE is a generic tool for managing angular masks on a sphere, it has the potential to benefit terrestrial mapmaking applications as well.

  3. A masking level difference due to harmonicity.

    PubMed

    Treurniet, W C; Boucher, D R

    2001-01-01

    The role of harmonicity in masking was studied by comparing the effect of harmonic and inharmonic maskers on the masked thresholds of noise probes using a three-alternative, forced-choice method. Harmonic maskers were created by selecting sets of partials from a harmonic series with an 88-Hz fundamental and 45 consecutive partials. Inharmonic maskers differed in that the partial frequencies were perturbed to nearby values that were not integer multiples of the fundamental frequency. Average simultaneous-masked thresholds were as much as 10 dB lower with the harmonic masker than with the inharmonic masker, and this difference was unaffected by masker level. It was reduced or eliminated when the harmonic partials were separated by more than 176 Hz, suggesting that the effect is related to the extent to which the harmonics are resolved by auditory filters. The threshold difference was not observed in a forward-masking experiment. Finally, an across-channel mechanism was implicated when the threshold difference was found between a harmonic masker flanked by harmonic bands and a harmonic masker flanked by inharmonic bands. A model developed to explain the observed difference recognizes that an auditory filter output envelope is modulated when the filter passes two or more sinusoids, and that the modulation rate depends on the differences among the input frequencies. For a harmonic masker, the frequency differences of adjacent partials are identical, and all auditory filters have the same dominant modulation rate. For an inharmonic masker, however, the frequency differences are not constant and the envelope modulation rate varies across filters. The model proposes that a lower variability facilitates detection of a probe-induced change in the variability, thus accounting for the masked threshold difference. The model was supported by significantly improved predictions of observed thresholds when the predictor variables included envelope modulation rate variance measured

  4. Mask industry assessment trend analysis

    NASA Astrophysics Data System (ADS)

    Shelden, Gilbert; Marmillion, Patricia; Hughes, Greg

    2008-04-01

    Microelectronics industry leaders routinely name the cost and cycle time of mask technology and mask supply as top critical issues. A survey was created with support from SEMATECH and administered by SEMI North America to gather information about the mask industry as an objective assessment of its overall condition. This year's survey data were presented in detail at BACUS and the detailed trend analysis presented at EMLC. The survey is designed with the input of semiconductor company mask technologists, merchant mask suppliers, and industry equipment makers. This year's assessment is the sixth in the current series of annual reports. With continued industry support, the report can be used as a baseline to gain perspective on the technical and business status of the mask and microelectronics industries. The report will continue to serve as a valuable reference to identify the strengths and opportunities of the mask industry. The results will be used to guide future investments on critical path issues. This year's survey is basically the same as the 2005 and 2006 surveys. Questions are grouped into eight categories: General Business Profile Information, Data Processing, Yields and Yield Loss, Mechanisms, Delivery Times, Returns and Services, Operating Cost Factors, and Equipment Utilization. Within each category is a multitude of questions that creates a detailed profile of both the business and technical status of the critical mask industry. Note: the questions covering operating cost factors and equipment utilization were added to the survey only in 2005; therefore, meaningful trend analysis is not available.

  5. Computing Challenges in Coded Mask Imaging

    NASA Technical Reports Server (NTRS)

    Skinner, Gerald

    2009-01-01

    This slide presaentation reviews the complications and challenges in developing computer systems for Coded Mask Imaging telescopes. The coded mask technique is used when there is no other way to create the telescope, (i.e., when there are wide fields of view, high energies for focusing or low energies for the Compton/Tracker Techniques and very good angular resolution.) The coded mask telescope is described, and the mask is reviewed. The coded Masks for the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) instruments are shown, and a chart showing the types of position sensitive detectors used for the coded mask telescopes is also reviewed. Slides describe the mechanism of recovering an image from the masked pattern. The correlation with the mask pattern is described. The Matrix approach is reviewed, and other approaches to image reconstruction are described. Included in the presentation is a review of the Energetic X-ray Imaging Survey Telescope (EXIST) / High Energy Telescope (HET), with information about the mission, the operation of the telescope, comparison of the EXIST/HET with the SWIFT/BAT and details of the design of the EXIST/HET.

  6. Orion Emergency Mask Approach

    NASA Technical Reports Server (NTRS)

    Tuan, George C.; Graf, John C.

    2008-01-01

    Emergency mask approach on Orion poses a challenge to the traditional Shuttle or Station approaches. Currently, in the case of a fire or toxic spill event, the crew utilizes open loop oxygen masks that provide the crew with oxygen to breath, but also dumps the exhaled oxygen into the cabin. For Orion, with a small cabin volume, the extra oxygen will exceed the flammability limit within a short period of time, unless a nitrogen purge is also provided. Another approach to a fire or toxic spill event is the use of a filtering emergency masks. These masks utilize some form of chemical beds to scrub the air clean of toxic providing the crew safe breathing air for a period without elevating the oxygen level in the cabin. Using the masks and a form of smoke-eater filter, it may be possible to clean the cabin completely or to a level for safe transition to a space suit to perform a cabin purge. Issues with filters in the past have been the reaction temperature and high breathing resistance. Development in a new form of chemical filters has shown promise to make the filtering approach feasible.

  7. Orion Emergency Mask Approach

    NASA Technical Reports Server (NTRS)

    Tuan, George C.; Graf, John C.

    2009-01-01

    Emergency mask approach on Orion poses a challenge to the traditional Shuttle or Station approaches. Currently, in the case of a fire or toxic spill event, the crew utilizes open loop oxygen masks that provide the crew with oxygen to breath, but also dumps the exhaled oxygen into the cabin. For Orion, with a small cabin volume, the extra oxygen will exceed the flammability limit within a short period of time, unless a nitrogen purge is also provided. Another approach to a fire or toxic spill event is the use of a filtering emergency masks. These masks utilize some form of chemical beds to scrub the air clean of toxic providing the crew safe breathing air for a period without elevating the oxygen level in the cabin. Using the masks and a form of smoke-eater filter, it may be possible to clean the cabin completely or to a level for safe transition to a space suit to perform a cabin purge. Issues with filters in the past have been the reaction time, breakthroughs, and high breathing resistance. Development in a new form of chemical filters has shown promise to make the filtering approach feasible.

  8. Interaural level differences do not suffice for restoring spatial release from masking in simulated cochlear implant listening.

    PubMed

    Ihlefeld, Antje; Litovsky, Ruth Y

    2012-01-01

    Spatial release from masking refers to a benefit for speech understanding. It occurs when a target talker and a masker talker are spatially separated. In those cases, speech intelligibility for target speech is typically higher than when both talkers are at the same location. In cochlear implant listeners, spatial release from masking is much reduced or absent compared with normal hearing listeners. Perhaps this reduced spatial release occurs because cochlear implant listeners cannot effectively attend to spatial cues. Three experiments examined factors that may interfere with deploying spatial attention to a target talker masked by another talker. To simulate cochlear implant listening, stimuli were vocoded with two unique features. First, we used 50-Hz low-pass filtered speech envelopes and noise carriers, strongly reducing the possibility of temporal pitch cues; second, co-modulation was imposed on target and masker utterances to enhance perceptual fusion between the two sources. Stimuli were presented over headphones. Experiments 1 and 2 presented high-fidelity spatial cues with unprocessed and vocoded speech. Experiment 3 maintained faithful long-term average interaural level differences but presented scrambled interaural time differences with vocoded speech. Results show a robust spatial release from masking in Experiments 1 and 2, and a greatly reduced spatial release in Experiment 3. Faithful long-term average interaural level differences were insufficient for producing spatial release from masking. This suggests that appropriate interaural time differences are necessary for restoring spatial release from masking, at least for a situation where there are few viable alternative segregation cues.

  9. Evaluation of human body irradiation caused by radionuclides deposited in the filtration unit of gas mask.

    PubMed

    Cerny, R; Johnova, K; Otahal, P; Thinova, L; Kluson, J

    2017-12-01

    Radioactive aerosol particles represent a serious risk for people facing the consequences of nuclear accident of any kind. The first responders to emergency situation need to be protected by personal protective equipment which includes radiation protection suit supplemented with gas mask. The purpose of this work is to estimate the dose to the organs of responder's body as a result of radionuclide deposition in the filtration unit of the gas mask. The problem was analyzed using Monte Carlo simulations. The dose absorbed by different organs for five representative radionuclides and the dose distribution over the responder's body are presented in this paper. Based on presented MC simulations, we suggest a method of evaluating the irradiation of the responder by the radionuclides deposited in the filtration unit of the gas mask. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Auditory Time-Frequency Masking for Spectrally and Temporally Maximally-Compact Stimuli

    PubMed Central

    Laback, Bernhard; Savel, Sophie; Ystad, Sølvi; Balazs, Peter; Meunier, Sabine; Kronland-Martinet, Richard

    2016-01-01

    Many audio applications perform perception-based time-frequency (TF) analysis by decomposing sounds into a set of functions with good TF localization (i.e. with a small essential support in the TF domain) using TF transforms and applying psychoacoustic models of auditory masking to the transform coefficients. To accurately predict masking interactions between coefficients, the TF properties of the model should match those of the transform. This involves having masking data for stimuli with good TF localization. However, little is known about TF masking for mathematically well-localized signals. Most existing masking studies used stimuli that are broad in time and/or frequency and few studies involved TF conditions. Consequently, the present study had two goals. The first was to collect TF masking data for well-localized stimuli in humans. Masker and target were 10-ms Gaussian-shaped sinusoids with a bandwidth of approximately one critical band. The overall pattern of results is qualitatively similar to existing data for long maskers. To facilitate implementation in audio processing algorithms, a dataset provides the measured TF masking function. The second goal was to assess the potential effect of auditory efferents on TF masking using a modeling approach. The temporal window model of masking was used to predict present and existing data in two configurations: (1) with standard model parameters (i.e. without efferents), (2) with cochlear gain reduction to simulate the activation of efferents. The ability of the model to predict the present data was quite good with the standard configuration but highly degraded with gain reduction. Conversely, the ability of the model to predict existing data for long maskers was better with than without gain reduction. Overall, the model predictions suggest that TF masking can be affected by efferent (or other) effects that reduce cochlear gain. Such effects were avoided in the experiment of this study by using maximally

  11. Lincoln's craniofacial microsomia: three-dimensional laser scanning of 2 Lincoln life masks.

    PubMed

    Fishman, Ronald S; Da Silveira, Adriana

    2007-08-01

    Examination of 2 life masks of Abraham Lincoln's face was performed by means of 3-dimensional laser surface scanning. This technique enabled documentation and analysis of Lincoln's facial contours and demonstrated his marked facial asymmetry, particularly evident in the smaller left superior orbital rim. This may have led to retroplacement of the trochlea on the left side, leading, in turn, to the mild superior oblique paresis that was manifested intermittently during adulthood.

  12. Evaluation of setup uncertainties for single-fraction SRS by comparing two different mask-creation methods

    NASA Astrophysics Data System (ADS)

    Baek, Jong Geun; Jang, Hyun Soo; Oh, Young Kee; Lee, Hyun Jeong; Kim, Eng Chan

    2015-07-01

    The purpose of this study was to evaluate the setup uncertainties for single-fraction stereotactic radiosurgery (SF-SRS) based on clinical data with two different mask-creation methods using pretreatment con-beam computed tomography imaging guidance. Dedicated frameless fixation Brain- LAB masks for 23 patients were created as a routine mask (R-mask) making method, as explained in the BrainLAB's user manual. Alternative masks (A-masks), which were created by modifying the cover range of the R-masks for the patient's head, were used for 23 patients. The systematic errors including these for each mask and stereotactic target localizer were analyzed, and the errors were calculated as the means ± standard deviations (SD) from the left-right (LR), superior-inferior (SI), anterior-posterior (AP), and yaw setup corrections. In addition, the frequencies of the threedimensional (3D) vector length were analyzed. The values of the mean setup corrections for the R-mask in all directions were < 0.7 mm and < 0.1°, whereas the magnitudes of the SDs were relatively large compared to the mean values. In contrast, the means and SDs of the A-mask were smaller than those for the R-mask with the exception of the SD in the AP direction. The means and SDs in the yaw rotational direction for the R-mask and the A-mask system were comparable. 3D vector shifts of larger magnitude occurred more frequently for the R-mask than the A-mask. The setup uncertainties for each mask with the stereotactic localizing system had an asymmetric offset towards the positive AP direction. The A-mask-creation method, which is capable of covering the top of the patient's head, is superior to that for the R-mask, so the use of the A-mask is encouraged for SF-SRS to reduce the setup uncertainties. Moreover, careful mask-making is required to prevent possible setup uncertainties.

  13. The use of masks and respirators to prevent transmission of influenza: a systematic review of the scientific evidence

    PubMed Central

    bin‐Reza, Faisal; Lopez Chavarrias, Vicente; Nicoll, Angus; Chamberland, Mary E.

    2011-01-01

    Please cite this paper as: bin‐Reza et al. (2012) The use of masks and respirators to prevent transmission of influenza: a systematic review of the scientific evidence. Influenza and Other Respiratory Viruses 6(4), 257–267. There are limited data on the use of masks and respirators to reduce transmission of influenza. A systematic review was undertaken to help inform pandemic influenza guidance in the United Kingdom. The initial review was performed in November 2009 and updated in June 2010 and January 2011. Inclusion criteria included randomised controlled trials and quasi‐experimental and observational studies of humans published in English with an outcome of laboratory‐confirmed or clinically‐diagnosed influenza and other viral respiratory infections. There were 17 eligible studies. Six of eight randomised controlled trials found no significant differences between control and intervention groups (masks with or without hand hygiene; N95/P2 respirators). One household trial found that mask wearing coupled with hand sanitiser use reduced secondary transmission of upper respiratory infection/influenza‐like illness/laboratory‐confirmed influenza compared with education; hand sanitiser alone resulted in no reduction. One hospital‐based trial found a lower rate of clinical respiratory illness associated with non‐fit‐tested N95 respirator use compared with medical masks. Eight of nine retrospective observational studies found that mask and/or respirator use was independently associated with a reduced risk of severe acute respiratory syndrome (SARS). Findings, however, may not be applicable to influenza and many studies were suboptimal. None of the studies established a conclusive relationship between mask/respirator use and protection against influenza infection. Some evidence suggests that mask use is best undertaken as part of a package of personal protection especially hand hygiene. The effectiveness of masks and respirators is likely linked to

  14. Metacontrast masking is processed before grapheme-color synesthesia.

    PubMed

    Bacon, Michael Patrick; Bridgeman, Bruce; Ramachandran, Vilayanur S

    2013-01-01

    We investigated the physiological mechanism of grapheme-color synesthesia using metacontrast masking. A metacontrast target is rendered invisible by a mask that is delayed by about 60 ms; the target and mask do not overlap in space or time. Little masking occurs, however, if the target and mask are simultaneous. This effect must be cortical, because it can be obtained dichoptically. To compare the data for synesthetes and controls, we developed a metacontrast design in which nonsynesthete controls showed weaker dichromatic masking (i.e., the target and mask were in different colors) than monochromatic masking. We accomplished this with an equiluminant target, mask, and background for each observer. If synesthetic color affected metacontrast, synesthetes should show monochromatic masking more similar to the weak dichromatic masking among controls, because synesthetes could add their synesthetic color to the monochromatic condition. The target-mask pairs used for each synesthete were graphemes that elicited strong synesthetic colors. We found stronger monochromatic than dichromatic U-shaped metacontrast for both synesthetes and controls, with optimal masking at an asynchrony of 66 ms. The difference in performance between the monochromatic and dichromatic conditions in the synesthetes indicates that synesthesia occurs at a later processing stage than does metacontrast masking.

  15. Temporal masking of multidimensional tactual stimuli

    NASA Astrophysics Data System (ADS)

    Tan, Hong Z.; Reed, Charlotte M.; Delhorne, Lorraine A.; Durlach, Nathaniel I.; Wan, Natasha

    2003-12-01

    Experiments were performed to examine the temporal masking properties of multidimensional tactual stimulation patterns delivered to the left index finger. The stimuli consisted of fixed-frequency sinusoidal motions in the kinesthetic (2 or 4 Hz), midfrequency (30 Hz), and cutaneous (300 Hz) frequency ranges. Seven stimuli composed of one, two, or three spectral components were constructed at each of two signal durations (125 or 250 ms). Subjects identified target signals under three different masking paradigms: forward masking, backward masking, and sandwiched masking (in which the target is presented between two maskers). Target identification was studied as a function of interstimulus interval (ISI) in the range 0 to 640 ms. For both signal durations, percent-correct scores increased with ISI for each of the three masking paradigms. Scores with forward and backward masking were similar and significantly higher than scores obtained with sandwiched masking. Analyses of error trials revealed that subjects showed a tendency to respond, more often than chance, with the masker, the composite of the masker and target, or the combination of the target and a component of the masker. The current results are compared to those obtained in previous studies of tactual recognition masking with brief cutaneous spatial patterns. The results are also discussed in terms of estimates of information transfer (IT) and IT rate, are compared to previous studies with multidimensional tactual signals, and are related to research on the development of tactual aids for the deaf.

  16. Mask industry assessment trend analysis: 2010

    NASA Astrophysics Data System (ADS)

    Hughes, Greg; Yun, Henry

    2010-05-01

    Microelectronics industry leaders consistently cite the cost and cycle time of mask technology and mask supply as top critical issues. A survey was designed with input from semiconductor company mask technologists and merchant mask suppliers and support from SEMATECH to gather information about the mask industry as an objective assessment of its overall condition. This year's assessment was the eighth in the current series of annual reports. Its data were presented in detail at BACUS, and the detailed trend analysis is presented at EMLC. With continued industry support, the report can be used as a baseline to gain perspective on the technical and business status of the mask and microelectronics industries. The report will continue to serve as a valuable reference to identify the strengths and opportunities of the mask industry. Its results will be used to guide future investments on critical path issues. This year's survey is basically the same as the surveys in 2005 through 2009. Questions are grouped into six categories: General Business Profile Information, Data Processing, Yields and Yield Loss Mechanisms, Delivery Times, Returns, and Services. Within each category is a multitude of questions that creates a detailed profile of both the business and technical status of the critical mask industry.

  17. An interactive tool for gamut masking

    NASA Astrophysics Data System (ADS)

    Song, Ying; Lau, Cheryl; Süsstrunk, Sabine

    2014-02-01

    Artists often want to change the colors of an image to achieve a particular aesthetic goal. For example, they might limit colors to a warm or cool color scheme to create an image with a certain mood or feeling. Gamut masking is a technique that artists use to limit the set of colors they can paint with. They draw a mask over a color wheel and only use the hues within the mask. However, creating the color palette from the mask and applying the colors to the image requires skill. We propose an interactive tool for gamut masking that allows amateur artists to create an image with a desired mood or feeling. Our system extracts a 3D color gamut from the 2D user-drawn mask and maps the image to this gamut. The user can draw a different gamut mask or locally refine the image colors. Our voxel grid gamut representation allows us to represent gamuts of any shape, and our cluster-based image representation allows the user to change colors locally.

  18. Masking of thresholds for the perception of fore-and-aft vibration of seat backrests.

    PubMed

    Morioka, Miyuki; Griffin, Michael J

    2015-09-01

    The detection of a vibration may be reduced by the presence of another vibration: a phenomenon known as 'masking'. This study investigated how the detection of one frequency of vibration is influenced by vibration at another frequency. With nine subjects, thresholds for detecting fore-and-aft backrest vibration were determined (for 4, 8, 16, and 31.5-Hz sinusoidal vibration) in the presence of a masker vibration (4-Hz random vibration, 1/3-octave bandwidth at six intensities). The masker vibration increased thresholds for perceiving vibration at each frequency by an amount that reduced with increasing difference between the frequency of the sinusoidal vibration and the frequency of the masker vibration. The 4-Hz random vibration almost completely masked 4-Hz sinusoidal vibration, partially masked 8- and 16-Hz vibration, and only slightly masked 31.5-Hz vibration. The findings might be explained by the involvement of different sensory systems and different body locations in the detection of different frequencies of vibration. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  19. Learning to recognize face shapes through serial exploration.

    PubMed

    Wallraven, Christian; Whittingstall, Lisa; Bülthoff, Heinrich H

    2013-05-01

    Human observers are experts at visual face recognition due to specialized visual mechanisms for face processing that evolve with perceptual expertize. Such expertize has long been attributed to the use of configural processing, enabled by fast, parallel information encoding of the visual information in the face. Here we tested whether participants can learn to efficiently recognize faces that are serially encoded-that is, when only partial visual information about the face is available at any given time. For this, ten participants were trained in gaze-restricted face recognition in which face masks were viewed through a small aperture controlled by the participant. Tests comparing trained with untrained performance revealed (1) a marked improvement in terms of speed and accuracy, (2) a gradual development of configural processing strategies, and (3) participants' ability to rapidly learn and accurately recognize novel exemplars. This performance pattern demonstrates that participants were able to learn new strategies to compensate for the serial nature of information encoding. The results are discussed in terms of expertize acquisition and relevance for other sensory modalities relying on serial encoding.

  20. [Recognition of visual objects under forward masking. Effects of cathegorial similarity of test and masking stimuli].

    PubMed

    Gerasimenko, N Iu; Slavutskaia, A V; Kalinin, S A; Kulikov, M A; Mikhaĭlova, E S

    2013-01-01

    In 38 healthy subjects accuracy and response time were examined during recognition of two categories of images--animals andnonliving objects--under forward masking. We revealed new data that masking effects depended of categorical similarity of target and masking stimuli. The recognition accuracy was the lowest and the response time was the most slow, when the target and masking stimuli belongs to the same category, that was combined with high dispersion of response times. The revealed effects were more clear in the task of animal recognition in comparison with the recognition of nonliving objects. We supposed that the revealed effects connected with interference between cortical representations of the target and masking stimuli and discussed our results in context of cortical interference and negative priming.

  1. Brain response to masked and unmasked facial emotions as a function of implicit and explicit personality self-concept of extraversion.

    PubMed

    Suslow, Thomas; Kugel, Harald; Lindner, Christian; Dannlowski, Udo; Egloff, Boris

    2017-01-06

    Extraversion-introversion is a personality dimension referring to individual differences in social behavior. In the past, neurobiological research on extraversion was almost entirely based upon questionnaires which inform about the explicit self-concept. Today, indirect measures are available that tap into the implicit self-concept of extraversion which is assumed to result from automatic processing functions. In our study, brain activation while viewing facial expression of affiliation relevant (i.e., happiness, and disgust) and irrelevant (i.e., fear) emotions was examined as a function of the implicit and explicit self-concept of extraversion and processing mode (automatic vs. controlled). 40 healthy volunteers watched blocks of masked and unmasked emotional faces while undergoing functional magnetic resonance imaging. The Implicit Association Test and the NEO Five-Factor Inventory were applied as implicit and explicit measures of extraversion which were uncorrelated in our sample. Implicit extraversion was found to be positively associated with neural response to masked happy faces in the thalamus and temporo-parietal regions and to masked disgust faces in cerebellar areas. Moreover, it was positively correlated with brain response to unmasked disgust faces in the amygdala and cortical areas. Explicit extraversion was not related to brain response to facial emotions when controlling trait anxiety. The implicit compared to the explicit self-concept of extraversion seems to be more strongly associated with brain activation not only during automatic but also during controlled processing of affiliation relevant facial emotions. Enhanced neural response to facial disgust could reflect high sensitivity to signals of interpersonal rejection in extraverts (i.e., individuals with affiliative tendencies). Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  2. The relationship between masking and short-term consolidation during recall from visual working memory.

    PubMed

    Ricker, Timothy J; Sandry, Joshua

    2018-04-10

    The presentation of a similar but irrelevant stimulus immediately following presentation of a memory item is called masking. Masking is known to reduce performance on working memory tests. This is the type of memory used to hold information in mind for brief periods of time for use in ongoing cognition. Two approaches to understanding masking effects have been proposed in different literatures. Working memory researchers often assume that the reduction in working memory performance after masking is because masking interferes with a transient sensory representation that is needed to complete consolidation into a working memory state. Researchers focused on the attentional blink, a finding that attention cannot be directed to new stimuli during working memory consolidation, have an alternative theory. Attentional blink researchers assume that masking slows the short-term consolidation process, thereby extending the length of the attentional blink. In two experiments, we contrast these two approaches to explaining masking effects and investigate the validity of both hypotheses. Some aspects of both approaches are validated, but neither theoretical perspective alone sufficiently explains the entire pattern of results. © 2018 New York Academy of Sciences.

  3. Oronasal masks require higher levels of positive airway pressure than nasal masks to treat obstructive sleep apnea.

    PubMed

    Bettinzoli, Michela; Taranto-Montemurro, Luigi; Messineo, Ludovico; Corda, Luciano; Redolfi, Stefania; Ferliga, Mauro; Tantucci, Claudio

    2014-12-01

    The purpose of this study was to compare the therapeutic pressure determined by an automated CPAP device (AutoCPAP) during the titration period, between nasal and oronasal mask and the residual apnea-hypopnea index (AHI) on a subsequent poligraphy performed with the established therapeutic CPAP. As a retrospective study, 109 subjects with moderate and severe obstructive sleep apnea-hypopnea (apnea-hypopnea index≥15 events/h) were studied. CPAP titration was performed using an auto-titrating device. There was significant difference in the mean pressure delivered with autoCPAP between the group of patients using the nasal mask (mean 10.0 cmH2O±2.0 SD) and the group which used the oronasal mask (mean 11.2 cmH2O±2.1) (p<0.05). Residual apneas were lower when using a nasal mask: average AHI of 2.6±2.5 compared to 4.5±4.0 using an oronasal mask (p<0.05). On multivariate analysis, the only independent predictor of the level of therapeutic pressure of CPAP was the type of mask used (r=0.245, p 0.008). Therapeutic CPAP level for OSAH is higher when administered via oronasal mask, leaving more residual events. These findings suggest that nasal mask should be the first choice for OSAH treatment.

  4. Recovering faces from memory: the distracting influence of external facial features.

    PubMed

    Frowd, Charlie D; Skelton, Faye; Atherton, Chris; Pitchford, Melanie; Hepton, Gemma; Holden, Laura; McIntyre, Alex H; Hancock, Peter J B

    2012-06-01

    Recognition memory for unfamiliar faces is facilitated when contextual cues (e.g., head pose, background environment, hair and clothing) are consistent between study and test. By contrast, inconsistencies in external features, especially hair, promote errors in unfamiliar face-matching tasks. For the construction of facial composites, as carried out by witnesses and victims of crime, the role of external features (hair, ears, and neck) is less clear, although research does suggest their involvement. Here, over three experiments, we investigate the impact of external features for recovering facial memories using a modern, recognition-based composite system, EvoFIT. Participant-constructors inspected an unfamiliar target face and, one day later, repeatedly selected items from arrays of whole faces, with "breeding," to "evolve" a composite with EvoFIT; further participants (evaluators) named the resulting composites. In Experiment 1, the important internal-features (eyes, brows, nose, and mouth) were constructed more identifiably when the visual presence of external features was decreased by Gaussian blur during construction: higher blur yielded more identifiable internal-features. In Experiment 2, increasing the visible extent of external features (to match the target's) in the presented face-arrays also improved internal-features quality, although less so than when external features were masked throughout construction. Experiment 3 demonstrated that masking external-features promoted substantially more identifiable images than using the previous method of blurring external-features. Overall, the research indicates that external features are a distractive rather than a beneficial cue for face construction; the results also provide a much better method to construct composites, one that should dramatically increase identification of offenders.

  5. Implicit reward associations impact face processing: Time-resolved evidence from event-related brain potentials and pupil dilations.

    PubMed

    Hammerschmidt, Wiebke; Kagan, Igor; Kulke, Louisa; Schacht, Annekathrin

    2018-06-22

    The present study aimed at investigating whether associated motivational salience causes preferential processing of inherently neutral faces similar to emotional expressions by means of event-related brain potentials (ERPs) and changes of the pupil size. To this aim, neutral faces were implicitly associated with monetary outcome, while participants (N = 44) performed a masked prime face-matching task that ensured performance around chance level and thus an equal proportion of gain, loss, and zero outcomes. Motivational context strongly impacted the processing of the fixation, prime and mask stimuli prior to the target face, indicated by enhanced amplitudes of subsequent ERP components and increased pupil size. In a separate test session, previously associated faces as well as novel faces with emotional expressions were presented within the same task but without motivational context and performance feedback. Most importantly, previously gain-associated faces amplified the LPC, although the individually contingent face-outcome assignments were not made explicit during the learning session. Emotional expressions impacted the N170 and EPN components. Modulations of the pupil size were absent in both motivationally-associated and emotional conditions. Our findings demonstrate that neural representations of neutral stimuli can acquire increased salience via implicit learning, with an advantage for gain over loss associations. Copyright © 2018. Published by Elsevier Inc.

  6. Lithography-based automation in the design of program defect masks

    NASA Astrophysics Data System (ADS)

    Vakanas, George P.; Munir, Saghir; Tejnil, Edita; Bald, Daniel J.; Nagpal, Rajesh

    2004-05-01

    In this work, we are reporting on a lithography-based methodology and automation in the design of Program Defect masks (PDM"s). Leading edge technology masks have ever-shrinking primary features and more pronounced model-based secondary features such as optical proximity corrections (OPC), sub-resolution assist features (SRAF"s) and phase-shifted mask (PSM) structures. In order to define defect disposition specifications for critical layers of a technology node, experience alone in deciding worst-case scenarios for the placement of program defects is necessary but may not be sufficient. MEEF calculations initiated from layout pattern data and their integration in a PDM layout flow provide a natural approach for improvements, relevance and accuracy in the placement of programmed defects. This methodology provides closed-loop feedback between layout and hard defect disposition specifications, thereby minimizing engineering test restarts, improving quality and reducing cost of high-end masks. Apart from SEMI and industry standards, best-known methods (BKM"s) in integrated lithographically-based layout methodologies and automation specific to PDM"s are scarce. The contribution of this paper lies in the implementation of Design-For-Test (DFT) principles to a synergistic interaction of CAD Layout and Aerial Image Simulator to drive layout improvements, highlight layout-to-fracture interactions and output accurate program defect placement coordinates to be used by tools in the mask shop.

  7. A tunable sub-100 nm silicon nanopore array with an AAO membrane mask: reducing unwanted surface etching by introducing a PMMA interlayer

    NASA Astrophysics Data System (ADS)

    Lim, Namsoo; Pak, Yusin; Kim, Jin Tae; Hwang, Youngkyu; Lee, Ryeri; Kumaresan, Yogeenth; Myoung, Nosoung; Ko, Heung Cho; Jung, Gun Young

    2015-08-01

    Highly ordered silicon (Si) nanopores with a tunable sub-100 nm diameter were fabricated by a CF4 plasma etching process using an anodic aluminum oxide (AAO) membrane as an etching mask. To enhance the conformal contact of the AAO membrane mask to the underlying Si substrate, poly(methyl methacrylate) (PMMA) was spin-coated on top of the Si substrate prior to the transfer of the AAO membrane. The AAO membrane mask was fabricated by two-step anodization and subsequent removal of the aluminum support and the barrier layer, which was then transferred to the PMMA-coated Si substrate. Contact printing was performed on the sample with a pressure of 50 psi and a temperature of 120 °C to make a conformal contact of the AAO membrane mask to the Si substrate. The CF4 plasma etching was conducted to transfer nanopores onto the Si substrate through the PMMA interlayer. The introduced PMMA interlayer prevented unwanted surface etching of the Si substrate by eliminating the etching ions and radicals bouncing at the gap between the mask and the substrate, resulting in a smooth Si nanopore array.Highly ordered silicon (Si) nanopores with a tunable sub-100 nm diameter were fabricated by a CF4 plasma etching process using an anodic aluminum oxide (AAO) membrane as an etching mask. To enhance the conformal contact of the AAO membrane mask to the underlying Si substrate, poly(methyl methacrylate) (PMMA) was spin-coated on top of the Si substrate prior to the transfer of the AAO membrane. The AAO membrane mask was fabricated by two-step anodization and subsequent removal of the aluminum support and the barrier layer, which was then transferred to the PMMA-coated Si substrate. Contact printing was performed on the sample with a pressure of 50 psi and a temperature of 120 °C to make a conformal contact of the AAO membrane mask to the Si substrate. The CF4 plasma etching was conducted to transfer nanopores onto the Si substrate through the PMMA interlayer. The introduced PMMA interlayer

  8. A new approach in dry technology for non-degrading optical and EUV mask cleaning

    NASA Astrophysics Data System (ADS)

    Varghese, Ivin; Smith, Ben; Balooch, Mehdi; Bowers, Chuck

    2012-11-01

    The Eco-Snow Systems group of RAVE N.P., Inc. has developed a new cleaning technique to target several of the advanced and next generation mask clean challenges. This new technique, especially when combined with Eco-Snow Systems cryogenic CO2 cleaning technology, provides several advantages over existing methods because it: 1) is solely based on dry technique without requiring additional complementary aggressive wet chemistries that degrade the mask, 2) operates at atmospheric pressure and therefore avoids expensive and complicated equipment associated with vacuum systems, 3) generates ultra-clean reactants eliminating possible byproduct adders, 4) can be applied locally for site specific cleaning without exposing the rest of the mask or can be used to clean the entire mask, 5) removes organic as well as inorganic particulates and film contaminations, and 6) complements current techniques utilized for cleaning of advanced masks such as reduced chemistry wet cleans. In this paper, we shall present examples demonstrating the capability of this new technique for removal of pellicle glue residues and for critical removal of carbon contamination on EUV masks.

  9. Are Masking-Based Models of Risk Useful?

    PubMed

    Gisiner, Robert C

    2016-01-01

    As our understanding of directly observable effects from anthropogenic sound exposure has improved, concern about "unobservable" effects such as stress and masking have received greater attention. Equal energy models of masking such as power spectrum models have the appeal of simplicity, but do they offer biologically realistic assessments of the risk of masking? Data relevant to masking such as critical ratios, critical bandwidths, temporal resolution, and directional resolution along with what is known about general mammalian antimasking mechanisms all argue for a much more complicated view of masking when making decisions about the risk of masking inherent in a given anthropogenic sound exposure scenario.

  10. The Sensitivity of Coded Mask Telescopes

    NASA Technical Reports Server (NTRS)

    Skinner, Gerald K.

    2008-01-01

    Simple formulae are often used to estimate the sensitivity of coded mask X-ray or gamma-ray telescopes, but t,hese are strictly only applicable if a number of basic assumptions are met. Complications arise, for example, if a grid structure is used to support the mask elements, if the detector spatial resolution is not good enough to completely resolve all the detail in the shadow of the mask or if any of a number of other simplifying conditions are not fulfilled. We derive more general expressions for the Poisson-noise-limited sensitivity of astronomical telescopes using the coded mask technique, noting explicitly in what circumstances they are applicable. The emphasis is on using nomenclature and techniques that result in simple and revealing results. Where no convenient expression is available a procedure is given which allows the calculation of the sensitivity. We consider certain aspects of the optimisation of the design of a coded mask telescope and show that when the detector spatial resolution and the mask to detector separation are fixed, the best source location accuracy is obtained when the mask elements are equal in size to the detector pixels.

  11. Blood, sweat and plaster casts: Reviewing the history, composition, and scientific value of the Raymond A. Dart Collection of African Life and Death Masks.

    PubMed

    Houlton, T M R; Billings, B K

    2017-10-01

    This paper addresses the history, composition and scientific value of one of the most comprehensive facemask collections in Africa, the Raymond A. Dart Collection of African Life and Death Masks. Housed within the School of Anatomical Sciences at the University of the Witwatersrand (South Africa), it comprises 1110 masks (397 life, 487 death, 226 unknown). Life masks represent populations throughout Africa; death masks predominately southern Africa. Males preponderate by 75%. Recorded ages are error prone, but suggest most life masks are those of <35 year-olds, death masks of 36+ year-olds. A total of 241 masks have associated skeletons, 209 presenting a complete skull. Life masks date between 1927 and c.1980s, death masks 1933 and 1963. This historical collection presents uncanny associations with outmoded typological and evolutionary theories. Once perceived an essential scientific resource, performed craniofacial superimpositions identify the nose as the only stable feature maintained, with the remaining face best preserved in young individuals with minimal body fat. The facemask collection is most viable for teaching and research within the history of science, specifically physical anthropology, and presents some value to craniofacial identification. Future research will have to be conducted with appropriate ethical considerations to science and medicine. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. Analysis of the ability of catcher's masks to attenuate head accelerations on impact with a baseball.

    PubMed

    Shain, Kellen S; Madigan, Michael L; Rowson, Steven; Bisplinghoff, Jill; Duma, Stefan M

    2010-11-01

    The goals of this study were to measure the ability of catcher's masks to attenuate head accelerations on impact with a baseball and to compare these head accelerations to established injury thresholds for mild traumatic brain injury. Testing involved using a pneumatic cannon to shoot baseballs at an instrumented Hybrid III headform (a 50th percentile male head and neck) with and without a catcher's mask on the head. The ball speed was controlled from approximately 26.8 to 35.8 m/s (60-80 mph), and the regulation National Collegiate Athletic Association baseballs were used. Research laboratory. None. Catcher's masks and impact velocity. The linear and angular head accelerations of the Hybrid III headform. Peak linear resultant acceleration was 140 to 180 g without a mask and 16 to 30 g with a mask over the range of ball's speed investigated. Peak angular resultant acceleration was 19 500 to 25 700 rad/s without a mask and 2250 to 3230 rad/s with a mask. The Head Injury Criterion was 93 to 181 without a mask and 3 to 13 with a mask, and the Severity Index was 110 to 210 without a mask and 3 to 15 with a mask. Catcher's masks reduced head acceleration metrics by approximately 85%. Head acceleration metrics with a catcher's mask were significantly lower than contemporary injury thresholds, yet reports in the mass media clearly indicate that baseball impacts to the mask still occasionally result in mild traumatic brain injuries. Further research is needed to address this apparent contradiction.

  13. Polarization masks: concept and initial assessment

    NASA Astrophysics Data System (ADS)

    Lam, Michael; Neureuther, Andrew R.

    2002-07-01

    Polarization from photomasks can be used as a new lever to improve lithographic performance in both binary and phase-shifting masks (PSMs). While PSMs manipulate the phase of light to control the temporal addition of electric field vectors, polarization masks manipulate the vector direction of electric field vectors to control the spatial addition of electric field components. This paper explores the theoretical possibilities of polarization masks, showing that it is possible to use bar structures within openings on the mask itself to polarize incident radiation. Rigorous electromagnetic scattering simulations using TEMPEST and imaging with SPLAT are used to give an initial assessment on the functionality of polarization masks, discussing the polarization quality and throughputs achieved with the masks. Openings between 1/8 and 1/3 of a wavelength provide both a low polarization ratio and good transmission. A final overall throughput of 33% - 40% is achievable, corresponding to a dose hit of 2.5x - 3x.

  14. Control of odour nuisance in urban areas: the efficiency and social acceptance of the application of masking agents.

    PubMed

    Lazarova, Valentina; Abed, Brahim; Markovska, Gabriela; Dezenclos, Thierry; Amara, Aït

    2013-01-01

    This paper presents and discusses the results of the project named 'Jasmin' implemented in Algiers to control the strong odours of the river named Oued El Harrach, one of the largest rivers in the centre of the city. Pending the achievement of curative solutions, a temporary option for mitigation of nuisance odour by masking agents was implemented in the vicinity of the main bridges. The efficiency of this technology has been followed by means of an odour panel with the participation of representatives of all stakeholders. A sociological study by means of 1,000 questionnaires and face-to-face interviews of the local population demonstrated the benefits and the positive outcomes of the attenuation of odour nuisance: 70% of the surveyed population is satisfied or very satisfied with the application of masking agents and 96% of respondents support the continuation of the project. In terms of size and public access, the project Jasmin is a world-first demonstration of odour control in urban areas in developing countries.

  15. 37 CFR 211.3 - Mask work fees.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Mask work fees. 211.3 Section... PROCEDURES MASK WORK PROTECTION § 211.3 Mask work fees. (a) Section 201.3 of this chapter prescribes the fees or charges established by the Register of Copyrights for services relating to mask works. (b) Section...

  16. 37 CFR 211.3 - Mask work fees.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Mask work fees. 211.3 Section... PROCEDURES MASK WORK PROTECTION § 211.3 Mask work fees. (a) Section 201.3 of this chapter prescribes the fees or charges established by the Register of Copyrights for services relating to mask works. (b) Section...

  17. Performance of repaired defects and attPSM in EUV multilayer masks

    NASA Astrophysics Data System (ADS)

    Deng, Yunfei; La Fontaine, Bruno; Neureuther, Andrew R.

    2002-12-01

    The imaging performance of non-planar topographies in EUV masks for both partially repaired defects and non-planar attenuating phase-shifting masks made with repair treatments are evaluated using rigorous electromagnetic simulation with TEMPEST. Typical topographies produced by treatment techniques in the literature such as removal of top layers and compaction produced by electron-beam heating are considered. Isolated defects on/near the surface repaired by material removal are shown to result in an image intensity within 5% of the clear field value. Deeply buried defects within the multilayer treated by electron-beam heating can be repaired to 3% of the clear field but over repair can result in some degradation. Compaction from a 6.938 nm period to a 6.312 nm period shows a 540° phase-shift and an intensity reduced to about 6% suggesting such a treatment may be used to create attenuated phase-shifting masks for EUV. The quality of the aerial image for such a mask is studied as a function of the lateral transition distance between treated and untreated regions.

  18. Orientation tuning of contrast masking caused by motion streaks.

    PubMed

    Apthorp, Deborah; Cass, John; Alais, David

    2010-08-01

    We investigated whether the oriented trails of blur left by fast-moving dots (i.e., "motion streaks") effectively mask grating targets. Using a classic overlay masking paradigm, we varied mask contrast and target orientation to reveal underlying tuning. Fast-moving Gaussian blob arrays elevated thresholds for detection of static gratings, both monoptically and dichoptically. Monoptic masking at high mask (i.e., streak) contrasts is tuned for orientation and exhibits a similar bandwidth to masking functions obtained with grating stimuli (∼30 degrees). Dichoptic masking fails to show reliable orientation-tuned masking, but dichoptic masks at very low contrast produce a narrowly tuned facilitation (∼17 degrees). For iso-oriented streak masks and grating targets, we also explored masking as a function of mask contrast. Interestingly, dichoptic masking shows a classic "dipper"-like TVC function, whereas monoptic masking shows no dip and a steeper "handle". There is a very strong unoriented component to the masking, which we attribute to transiently biased temporal frequency masking. Fourier analysis of "motion streak" images shows interesting differences between dichoptic and monoptic functions and the information in the stimulus. Our data add weight to the growing body of evidence that the oriented blur of motion streaks contributes to the processing of fast motion signals.

  19. The Meaning behind the Mask. [Lesson Plan].

    ERIC Educational Resources Information Center

    National Endowment for the Humanities (NFAH), Washington, DC.

    In this lesson plan, students explore the cultural significance of masks. After exploring the world of African masks and storytelling, they create masks that tell stories of their own. In these six lessons, students first recall contexts in which masks are worn in the United States, and then discuss their use in stories. Students then investigate…

  20. Metacontrast masking and attention do not interact.

    PubMed

    Agaoglu, Sevda; Breitmeyer, Bruno; Ogmen, Haluk

    2016-07-01

    Visual masking and attention have been known to control the transfer of information from sensory memory to visual short-term memory. A natural question is whether these processes operate independently or interact. Recent evidence suggests that studies that reported interactions between masking and attention suffered from ceiling and/or floor effects. The objective of the present study was to investigate whether metacontrast masking and attention interact by using an experimental design in which saturation effects are avoided. We asked observers to report the orientation of a target bar randomly selected from a display containing either two or six bars. The mask was a ring that surrounded the target bar. Attentional load was controlled by set-size and masking strength by the stimulus onset asynchrony between the target bar and the mask ring. We investigated interactions between masking and attention by analyzing two different aspects of performance: (i) the mean absolute response errors and (ii) the distribution of signed response errors. Our results show that attention affects observers' performance without interacting with masking. Statistical modeling of response errors suggests that attention and metacontrast masking exert their effects by independently modulating the probability of "guessing" behavior. Implications of our findings for models of attention are discussed.

  1. 21 CFR 868.5590 - Scavenging mask.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Scavenging mask. 868.5590 Section 868.5590 Food... DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5590 Scavenging mask. (a) Identification. A scavenging mask is a device positioned over a patient's nose to deliver anesthetic or analgesic gases to the...

  2. 21 CFR 868.5600 - Venturi mask.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Venturi mask. 868.5600 Section 868.5600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5600 Venturi mask. (a) Identification. A venturi mask is a...

  3. An open-architecture approach to defect analysis software for mask inspection systems

    NASA Astrophysics Data System (ADS)

    Pereira, Mark; Pai, Ravi R.; Reddy, Murali Mohan; Krishna, Ravi M.

    2009-04-01

    Industry data suggests that Mask Inspection represents the second biggest component of Mask Cost and Mask Turn Around Time (TAT). Ever decreasing defect size targets lead to more sensitive mask inspection across the chip, thus generating too many defects. Hence, more operator time is being spent in analyzing and disposition of defects. Also, the fact that multiple Mask Inspection Systems and Defect Analysis strategies would typically be in use in a Mask Shop or a Wafer Foundry further complicates the situation. In this scenario, there is a need for a versatile, user friendly and extensible Defect Analysis software that reduces operator analysis time and enables correct classification and disposition of mask defects by providing intuitive visual and analysis aids. We propose a new vendor-neutral defect analysis software, NxDAT, based on an open architecture. The open architecture of NxDAT makes it easily extensible to support defect analysis for mask inspection systems from different vendors. The capability to load results from mask inspection systems from different vendors either directly or through a common interface enables the functionality of establishing correlation between inspections carried out by mask inspection systems from different vendors. This capability of NxDAT enhances the effectiveness of defect analysis as it directly addresses the real-life scenario where multiple types of mask inspection systems from different vendors co-exist in mask shops or wafer foundries. The open architecture also potentially enables loading wafer inspection results as well as loading data from other related tools such as Review Tools, Repair Tools, CD-SEM tools etc, and correlating them with the corresponding mask inspection results. A unique concept of Plug-In interface to NxDAT further enhances the openness of the architecture of NxDAT by enabling end-users to add their own proprietary defect analysis and image processing algorithms. The plug-in interface makes it

  4. Fabrication of coronagraph masks and laboratory scale star-shade masks: characteristics, defects, and performance

    NASA Astrophysics Data System (ADS)

    Balasubramanian, Kunjithapatham; Riggs, A. J. Eldorado; Cady, Eric; White, Victor; Yee, Karl; Wilson, Daniel; Echternach, Pierre; Muller, Richard; Mejia Prada, Camilo; Seo, Byoung-Joon; Shi, Fang; Ryan, Daniel; Fregoso, Santos; Metzman, Jacob; Wilson, Robert Casey

    2017-09-01

    NASA WFIRST mission has planned to include a coronagraph instrument to find and characterize exoplanets. Masks are needed to suppress the host star light to better than 10-8 - 10-9 level contrast over a broad bandwidth to enable the coronagraph mission objectives. Such masks for high contrast coronagraphic imaging require various fabrication technologies to meet a wide range of specifications, including precise shapes, micron scale island features, ultra-low reflectivity regions, uniformity, wave front quality, etc. We present the technologies employed at JPL to produce these pupil plane and image plane coronagraph masks, and lab-scale external occulter masks, highlighting accomplishments from the high contrast imaging testbed (HCIT) at JPL and from the high contrast imaging lab (HCIL) at Princeton University. Inherent systematic and random errors in fabrication and their impact on coronagraph performance are discussed with model predictions and measurements.

  5. Process optimization for particle removal on blank chrome mask plates in preparation for resist application

    NASA Astrophysics Data System (ADS)

    Osborne, Stephen; Smith, Eryn; Woster, Eric; Pelayo, Anthony

    2002-03-01

    As integrated circuits require smaller lines to provide the memory and processing capability for tomorrow's marketplace, the photomask industry is adopting higher contrast resists to improve photomask lithography. Photomask yield for several high-contrast resist recipes may be improved by coating masks at the mask shop. When coating at a mask shop, an effective method is available that uses coat/bake cluster tools to ensure blanks are clean prior to coating. Many high-contrast resists are available, and some are more susceptible to time-dependent performance factors than conventional resists. One of these factors is the time between coating and writing. Although future methods may reduce the impact of this factor, one current trend is to reduce this time by coating plates at the mask shop just prior to writing. Establishing an effective process to clean blanks prior to coating is necessary for product quality control and is a new task that is critical for maskmakers who previously purchased mask plates but have decided to begin coating them within their facility. This paper provides a strategy and method to be used within coat/bake cluster tools to remove particle contamination from mask blanks. The process uses excimer-UV ionizing radiation and ozone to remove organic contaminants, and then uses a wet process combined with megasonic agitation, surfactant, and spin forces. Megasonic agitation with surfactant lifts up particles, while the convective outflow of water enhances centripetal shear without accumulating harmful charge.

  6. Alternative method for variable aspect ratio vias using a vortex mask

    NASA Astrophysics Data System (ADS)

    Schepis, Anthony R.; Levinson, Zac; Burbine, Andrew; Smith, Bruce W.

    2014-03-01

    Historically IC (integrated circuit) device scaling has bridged the gap between technology nodes. Device size reduction is enabled by increased pattern density, enhancing functionality and effectively reducing cost per chip. Exemplifying this trend are aggressive reductions in memory cell sizes that have resulted in systems with diminishing area between bit/word lines. This affords an even greater challenge in the patterning of contact level features that are inherently difficult to resolve because of their relatively small area and complex aerial image. To accommodate these trends, semiconductor device design has shifted toward the implementation of elliptical contact features. This empowers designers to maximize the use of free device space, preserving contact area and effectively reducing the via dimension just along a single axis. It is therefore critical to provide methods that enhance the resolving capacity of varying aspect ratio vias for implementation in electronic design systems. Vortex masks, characterized by their helically induced propagation of light and consequent dark core, afford great potential for the patterning of such features when coupled with a high resolution negative tone resist system. This study investigates the integration of a vortex mask in a 193nm immersion (193i) lithography system and qualifies its ability to augment aspect ratio through feature density using aerial image vector simulation. It was found that vortex fabricated vias provide a distinct resolution advantage over traditionally patterned contact features employing a 6% attenuated phase shift mask (APM). 1:1 features were resolvable at 110nm pitch with a 38nm critical dimension (CD) and 110nm depth of focus (DOF) at 10% exposure latitude (EL). Furthermore, iterative source-mask optimization was executed as means to augment aspect ratio. By employing mask asymmetries and directionally biased sources aspect ratios ranging between 1:1 and 2:1 were achievable, however, this

  7. Masked Chimeric Antigen Receptor for Tumor-Specific Activation.

    PubMed

    Han, Xiaolu; Bryson, Paul D; Zhao, Yifan; Cinay, Gunce E; Li, Si; Guo, Yunfei; Siriwon, Natnaree; Wang, Pin

    2017-01-04

    Adoptive cellular therapy based on chimeric antigen receptor (CAR)-engineered T (CAR-T) cells is a powerful form of cancer immunotherapy. CAR-T cells can be redirected to specifically recognize tumor-associated antigens (TAAs) and induce high levels of antitumor activity. However, they may also display "on-target off-tumor" toxicities, resulting from low-level expression of TAAs in healthy tissues. These adverse effects have raised considerable safety concerns and limited the clinical application of this otherwise promising therapeutic modality. To minimize such side effects, we have designed an epidermal growth factor receptor (EGFR)-specific masked CAR (mCAR), which consists of a masking peptide that blocks the antigen-binding site and a protease-sensitive linker. Proteases commonly active in the tumor microenvironment can cleave the linker and disengage the masking peptide, thereby enabling CAR-T cells to recognize target antigens only at the tumor site. In vitro mCAR showed dramatically reduced antigen binding and antigen-specific activation in the absence of proteases, but normal levels of binding and activity upon treatment with certain proteases. Masked CAR-T cells also showed antitumor efficacy in vivo comparable to that of unmasked CAR. Our study demonstrates the feasibility of improving the safety profile of conventional CARs and may also inspire future design of CAR molecules targeting broadly expressed TAAs. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

  8. 21 CFR 868.5580 - Oxygen mask.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Oxygen mask. 868.5580 Section 868.5580 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5580 Oxygen mask. (a) Identification. An oxygen mask is a device placed over a patient's nose, mouth, or tracheostomy to administer oxygen or aerosols. (b) Classification...

  9. 21 CFR 868.5580 - Oxygen mask.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Oxygen mask. 868.5580 Section 868.5580 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5580 Oxygen mask. (a) Identification. An oxygen mask is a device placed over a patient's nose, mouth, or tracheostomy to administer oxygen or aerosols. (b) Classification...

  10. 21 CFR 868.5580 - Oxygen mask.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Oxygen mask. 868.5580 Section 868.5580 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5580 Oxygen mask. (a) Identification. An oxygen mask is a device placed over a patient's nose, mouth, or tracheostomy to administer oxygen or aerosols. (b) Classification...

  11. 21 CFR 868.5580 - Oxygen mask.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Oxygen mask. 868.5580 Section 868.5580 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5580 Oxygen mask. (a) Identification. An oxygen mask is a device placed over a patient's nose, mouth, or tracheostomy to administer oxygen or aerosols. (b) Classification...

  12. 21 CFR 868.5580 - Oxygen mask.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Oxygen mask. 868.5580 Section 868.5580 Food and... ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5580 Oxygen mask. (a) Identification. An oxygen mask is a device placed over a patient's nose, mouth, or tracheostomy to administer oxygen or aerosols. (b) Classification...

  13. Informational Masking Effects on Neural Encoding of Stimulus Onset and Acoustic Change.

    PubMed

    Niemczak, Christopher E; Vander Werff, Kathy R

    2018-05-18

    Recent investigations using cortical auditory evoked potentials have shown masker-dependent effects on sensory cortical processing of speech information. Background noise maskers consisting of other people talking are particularly difficult for speech recognition. Behavioral studies have related this to perceptual masking, or informational masking, beyond just the overlap of the masker and target at the auditory periphery. The aim of the present study was to use cortical auditory evoked potentials, to examine how maskers (i.e., continuous speech-shaped noise [SSN] and multi-talker babble) affect the cortical sensory encoding of speech information at an obligatory level of processing. Specifically, cortical responses to vowel onset and formant change were recorded under different background noise conditions presumed to represent varying amounts of energetic or informational masking. The hypothesis was, that even at this obligatory cortical level of sensory processing, we would observe larger effects on the amplitude and latency of the onset and change components as the amount of informational masking increased across background noise conditions. Onset and change responses were recorded to a vowel change from /u-i/ in young adults under four conditions: quiet, continuous SSN, eight-talker (8T) babble, and two-talker (2T) babble. Repeated measures analyses by noise condition were conducted on amplitude, latency, and response area measurements to determine the differential effects of these noise conditions, designed to represent increasing and varying levels of informational and energetic masking, on cortical neural representation of a vowel onset and acoustic change response waveforms. All noise conditions significantly reduced onset N1 and P2 amplitudes, onset N1-P2 peak to peak amplitudes, as well as both onset and change response area compared with quiet conditions. Further, all amplitude and area measures were significantly reduced for the two babble conditions

  14. Ensuring Confidentiality of Geocoded Health Data: Assessing Geographic Masking Strategies for Individual-Level Data.

    PubMed

    Zandbergen, Paul A

    2014-01-01

    Public health datasets increasingly use geographic identifiers such as an individual's address. Geocoding these addresses often provides new insights since it becomes possible to examine spatial patterns and associations. Address information is typically considered confidential and is therefore not released or shared with others. Publishing maps with the locations of individuals, however, may also breach confidentiality since addresses and associated identities can be discovered through reverse geocoding. One commonly used technique to protect confidentiality when releasing individual-level geocoded data is geographic masking. This typically consists of applying a certain amount of random perturbation in a systematic manner to reduce the risk of reidentification. A number of geographic masking techniques have been developed as well as methods to quantity the risk of reidentification associated with a particular masking method. This paper presents a review of the current state-of-the-art in geographic masking, summarizing the various methods and their strengths and weaknesses. Despite recent progress, no universally accepted or endorsed geographic masking technique has emerged. Researchers on the other hand are publishing maps using geographic masking of confidential locations. Any researcher publishing such maps is advised to become familiar with the different masking techniques available and their associated reidentification risks.

  15. Masking release by combined spatial and masker-fluctuation effects in the open sound field.

    PubMed

    Middlebrooks, John C

    2017-12-01

    In a complex auditory scene, signals of interest can be distinguished from masking sounds by differences in source location [spatial release from masking (SRM)] and by differences between masker-alone and masker-plus-signal envelopes. This study investigated interactions between those factors in release of masking of 700-Hz tones in an open sound field. Signal and masker sources were colocated in front of the listener, or the signal source was shifted 90° to the side. In Experiment 1, the masker contained a 25-Hz-wide on-signal band plus flanking bands having envelopes that were either mutually uncorrelated or were comodulated. Comodulation masking release (CMR) was largely independent of signal location at a higher masker sound level, but at a lower level CMR was reduced for the lateral signal location. In Experiment 2, a brief signal was positioned at the envelope maximum (peak) or minimum (dip) of a 50-Hz-wide on-signal masker. Masking was released in dip more than in peak conditions only for the 90° signal. Overall, open-field SRM was greater in magnitude than binaural masking release reported in comparable closed-field studies, and envelope-related release was somewhat weaker. Mutual enhancement of masking release by spatial and envelope-related effects tended to increase with increasing masker level.

  16. Ensuring Confidentiality of Geocoded Health Data: Assessing Geographic Masking Strategies for Individual-Level Data

    PubMed Central

    Zandbergen, Paul A.

    2014-01-01

    Public health datasets increasingly use geographic identifiers such as an individual's address. Geocoding these addresses often provides new insights since it becomes possible to examine spatial patterns and associations. Address information is typically considered confidential and is therefore not released or shared with others. Publishing maps with the locations of individuals, however, may also breach confidentiality since addresses and associated identities can be discovered through reverse geocoding. One commonly used technique to protect confidentiality when releasing individual-level geocoded data is geographic masking. This typically consists of applying a certain amount of random perturbation in a systematic manner to reduce the risk of reidentification. A number of geographic masking techniques have been developed as well as methods to quantity the risk of reidentification associated with a particular masking method. This paper presents a review of the current state-of-the-art in geographic masking, summarizing the various methods and their strengths and weaknesses. Despite recent progress, no universally accepted or endorsed geographic masking technique has emerged. Researchers on the other hand are publishing maps using geographic masking of confidential locations. Any researcher publishing such maps is advised to become familiar with the different masking techniques available and their associated reidentification risks. PMID:26556417

  17. Enhancement in Informational Masking

    ERIC Educational Resources Information Center

    Cao, Xiang; Richards, Virginia M.

    2012-01-01

    Purpose: The ability to detect a tone added to a random masker improves when a preview of the masker is provided. In 2 experiments, the authors explored the role that perceptual organization plays in this release from masking. Method: Detection thresholds were measured in informational masking studies. The maskers were drawn at random prior to…

  18. Etching Selectivity of Cr, Fe and Ni Masks on Si & SiO2 Wafers

    NASA Astrophysics Data System (ADS)

    Garcia, Jorge; Lowndes, Douglas H.

    2000-10-01

    During this Summer 2000 I joined the Semiconductors and Thin Films group led by Dr. Douglas H. Lowndes at Oak Ridge National Laboratory’s Solid State Division. Our objective was to evaluate the selectivity that Trifluoromethane (CHF3), and Sulfur Hexafluoride (SF6) plasmas have for Si, SiO2 wafers and the Ni, Cr, and Fe masks; being this etching selectivity the ratio of the etching rates of the plasmas for each of the materials. We made use of Silicon and Silicon Dioxide-coated wafers that have Fe, Cr or Ni masks. In the semiconductor field, metal layers are often used as masks to protect layers underneath during processing steps; when these wafers are taken to the dry etching process, both the wafer and the mask layers’ thickness are reduced.

  19. Simulation-based MDP verification for leading-edge masks

    NASA Astrophysics Data System (ADS)

    Su, Bo; Syrel, Oleg; Pomerantsev, Michael; Hagiwara, Kazuyuki; Pearman, Ryan; Pang, Leo; Fujimara, Aki

    2017-07-01

    For IC design starts below the 20nm technology node, the assist features on photomasks shrink well below 60nm and the printed patterns of those features on masks written by VSB eBeam writers start to show a large deviation from the mask designs. Traditional geometry-based fracturing starts to show large errors for those small features. As a result, other mask data preparation (MDP) methods have become available and adopted, such as rule-based Mask Process Correction (MPC), model-based MPC and eventually model-based MDP. The new MDP methods may place shot edges slightly differently from target to compensate for mask process effects, so that the final patterns on a mask are much closer to the design (which can be viewed as the ideal mask), especially for those assist features. Such an alteration generally produces better masks that are closer to the intended mask design. Traditional XOR-based MDP verification cannot detect problems caused by eBeam effects. Much like model-based OPC verification which became a necessity for OPC a decade ago, we see the same trend in MDP today. Simulation-based MDP verification solution requires a GPU-accelerated computational geometry engine with simulation capabilities. To have a meaningful simulation-based mask check, a good mask process model is needed. The TrueModel® system is a field tested physical mask model developed by D2S. The GPU-accelerated D2S Computational Design Platform (CDP) is used to run simulation-based mask check, as well as model-based MDP. In addition to simulation-based checks such as mask EPE or dose margin, geometry-based rules are also available to detect quality issues such as slivers or CD splits. Dose margin related hotspots can also be detected by setting a correct detection threshold. In this paper, we will demonstrate GPU-acceleration for geometry processing, and give examples of mask check results and performance data. GPU-acceleration is necessary to make simulation-based mask MDP verification

  20. The impact of reverberant self-masking and overlap-masking effects on speech intelligibility by cochlear implant listeners (L).

    PubMed

    Kokkinakis, Kostas; Loizou, Philipos C

    2011-09-01

    The purpose of this study is to determine the relative impact of reverberant self-masking and overlap-masking effects on speech intelligibility by cochlear implant listeners. Sentences were presented in two conditions wherein reverberant consonant segments were replaced with clean consonants, and in another condition wherein reverberant vowel segments were replaced with clean vowels. The underlying assumption is that self-masking effects would dominate in the first condition, whereas overlap-masking effects would dominate in the second condition. Results indicated that the degradation of speech intelligibility in reverberant conditions is caused primarily by self-masking effects that give rise to flattened formant transitions. © 2011 Acoustical Society of America

  1. The edge of awareness: Mask spatial density, but not color, determines optimal temporal frequency for continuous flash suppression.

    PubMed

    Drewes, Jan; Zhu, Weina; Melcher, David

    2018-01-01

    The study of how visual processing functions in the absence of visual awareness has become a major research interest in the vision-science community. One of the main sources of evidence that stimuli that do not reach conscious awareness-and are thus "invisible"-are still processed to some degree by the visual system comes from studies using continuous flash suppression (CFS). Why and how CFS works may provide more general insight into how stimuli access awareness. As spatial and temporal properties of stimuli are major determinants of visual perception, we hypothesized that these properties of the CFS masks would be of significant importance to the achieved suppression depth. In previous studies however, the spatial and temporal properties of the masks themselves have received little study, and masking parameters vary widely across studies, making a metacomparison difficult. To investigate the factors that determine the effectiveness of CFS, we varied both the temporal frequency and the spatial density of Mondrian-style masks. We consistently found the longest suppression duration for a mask temporal frequency of around 6 Hz. In trials using masks with reduced spatial density, suppression was weaker and frequency tuning was less precise. In contrast, removing color reduced mask effectiveness but did not change the pattern of suppression strength as a function of frequency. Overall, this pattern of results stresses the importance of CFS mask parameters and is consistent with the idea that CFS works by disrupting the spatiotemporal mechanisms that underlie conscious access to visual input.

  2. Electrical Stimulation over Bilateral Occipito-Temporal Regions Reduces N170 in the Right Hemisphere and the Composite Face Effect

    PubMed Central

    Yang, Li-Zhuang; Zhang, Wei; Shi, Bin; Yang, Zhiyu; Wei, Zhengde; Gu, Feng; Zhang, Jing; Cui, Guanbao; Liu, Ying; Zhou, Yifeng; Zhang, Xiaochu; Rao, Hengyi

    2014-01-01

    Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that can modulate cortical excitability. Although the clinical value of tDCS has been advocated, the potential of tDCS in cognitive rehabilitation of face processing deficits is less understood. Face processing has been associated with the occipito-temporal cortex (OT). The present study investigated whether face processing in healthy adults can be modulated by applying tDCS over the OT. Experiment 1 investigated whether tDCS can affect N170, a face-sensitive ERP component, with a face orientation judgment task. The N170 in the right hemisphere was reduced in active stimulation conditions compared with the sham stimulation condition for both upright faces and inverted faces. Experiment 2 further demonstrated that tDCS can modulate the composite face effect, a type of holistic processing that reflects the obligatory attention to all parts of a face. The composite face effect was reduced in active stimulation conditions compared with the sham stimulation condition. Additionally, the current polarity did not modulate the effect of tDCS in the two experiments. The present study demonstrates that N170 can be causally manipulated by stimulating the OT with weak currents. Furthermore, our study provides evidence that obligatory attention to all parts of a face can be affected by the commonly used tDCS parameter setting. PMID:25531112

  3. Masking of a circadian behavior in larval zebrafish involves the thalamo-habenula pathway.

    PubMed

    Lin, Qian; Jesuthasan, Suresh

    2017-06-22

    Changes in illumination can rapidly influence behavior that is normally controlled by the circadian clock. This effect is termed masking. In mice, masking requires melanopsin-expressing retinal ganglion cells that detect blue light and project to the thalamus. It is not known whether masking is wavelength-dependent in other vertebrates, nor is it known whether the thalamus is also involved or how it influences masking. Here, we address these questions in zebrafish. We find that diel vertical migration, a circadian behavior in larval zebrafish, is effectively triggered by blue, but not by red light. Two-photon calcium imaging reveals that a thalamic nucleus and a downstream structure, the habenula, have a sustained response to blue but not to red light. Lesioning the habenula reduces light-evoked climbing. These data suggest that the thalamo-habenula pathway is involved in the ability of blue light to influence a circadian behavior.

  4. Ion beam deposition system for depositing low defect density extreme ultraviolet mask blanks

    NASA Astrophysics Data System (ADS)

    Jindal, V.; Kearney, P.; Sohn, J.; Harris-Jones, J.; John, A.; Godwin, M.; Antohe, A.; Teki, R.; Ma, A.; Goodwin, F.; Weaver, A.; Teora, P.

    2012-03-01

    Extreme ultraviolet lithography (EUVL) is the leading next-generation lithography (NGL) technology to succeed optical lithography at the 22 nm node and beyond. EUVL requires a low defect density reflective mask blank, which is considered to be one of the top two critical technology gaps for commercialization of the technology. At the SEMATECH Mask Blank Development Center (MBDC), research on defect reduction in EUV mask blanks is being pursued using the Veeco Nexus deposition tool. The defect performance of this tool is one of the factors limiting the availability of defect-free EUVL mask blanks. SEMATECH identified the key components in the ion beam deposition system that is currently impeding the reduction of defect density and the yield of EUV mask blanks. SEMATECH's current research is focused on in-house tool components to reduce their contributions to mask blank defects. SEMATECH is also working closely with the supplier to incorporate this learning into a next-generation deposition tool. This paper will describe requirements for the next-generation tool that are essential to realize low defect density EUV mask blanks. The goal of our work is to enable model-based predictions of defect performance and defect improvement for targeted process improvement and component learning to feed into the new deposition tool design. This paper will also highlight the defect reduction resulting from process improvements and the restrictions inherent in the current tool geometry and components that are an impediment to meeting HVM quality EUV mask blanks will be outlined.

  5. Parallel compression/decompression-based datapath architecture for multibeam mask writers

    NASA Astrophysics Data System (ADS)

    Chaudhary, Narendra; Savari, Serap A.

    2017-06-01

    Multibeam electron beam systems will be used in the future for mask writing and for complimentary lithography. The major challenges of the multibeam systems are in meeting throughput requirements and in handling the large data volumes associated with writing grayscale data on the wafer. In terms of future communications and computational requirements Amdahl's Law suggests that a simple increase of computation power and parallelism may not be a sustainable solution. We propose a parallel data compression algorithm to exploit the sparsity of mask data and a grayscale video-like representation of data. To improve the communication and computational efficiency of these systems at the write time we propose an alternate datapath architecture partly motivated by multibeam direct write lithography and partly motivated by the circuit testing literature, where parallel decompression reduces clock cycles. We explain a deflection plate architecture inspired by NuFlare Technology's multibeam mask writing system and how our datapath architecture can be easily added to it to improve performance.

  6. Parallel compression/decompression-based datapath architecture for multibeam mask writers

    NASA Astrophysics Data System (ADS)

    Chaudhary, Narendra; Savari, Serap A.

    2017-10-01

    Multibeam electron beam systems will be used in the future for mask writing and for complementary lithography. The major challenges of the multibeam systems are in meeting throughput requirements and in handling the large data volumes associated with writing grayscale data on the wafer. In terms of future communications and computational requirements, Amdahl's law suggests that a simple increase of computation power and parallelism may not be a sustainable solution. We propose a parallel data compression algorithm to exploit the sparsity of mask data and a grayscale video-like representation of data. To improve the communication and computational efficiency of these systems at the write time, we propose an alternate datapath architecture partly motivated by multibeam direct-write lithography and partly motivated by the circuit testing literature, where parallel decompression reduces clock cycles. We explain a deflection plate architecture inspired by NuFlare Technology's multibeam mask writing system and how our datapath architecture can be easily added to it to improve performance.

  7. Quantitative evaluation of manufacturability and performance for ILT produced mask shapes using a single-objective function

    NASA Astrophysics Data System (ADS)

    Choi, Heon; Wang, Wei-long; Kallingal, Chidam

    2015-03-01

    The continuous scaling of semiconductor devices is quickly outpacing the resolution improvements of lithographic exposure tools and processes. This one-sided progression has pushed optical lithography to its limits, resulting in the use of well-known techniques such as Sub-Resolution Assist Features (SRAF's), Source-Mask Optimization (SMO), and double-patterning, to name a few. These techniques, belonging to a larger category of Resolution Enhancement Techniques (RET), have extended the resolution capabilities of optical lithography at the cost of increasing mask complexity, and therefore cost. One such technique, called Inverse Lithography Technique (ILT), has attracted much attention for its ability to produce the best possible theoretical mask design. ILT treats the mask design process as an inverse problem, where the known transformation from mask to wafer is carried out backwards using a rigorous mathematical approach. One practical problem in the application of ILT is the resulting contour-like mask shapes that must be "Manhattanized" (composed of straight edges and 90-deg corners) in order to produce a manufacturable mask. This conversion process inherently degrades the mask quality as it is a departure from the "optimal mask" represented by the continuously curved shapes produced by ILT. However, simpler masks composed of longer straight edges reduce the mask cost as it lowers the shot count and saves mask writing time during mask fabrication, resulting in a conflict between manufacturability and performance for ILT produced masks1,2. In this study, various commonly used metrics will be combined into an objective function to produce a single number to quantitatively measure a particular ILT solution's ability to balance mask manufacturability and RET performance. Several metrics that relate to mask manufacturing costs (i.e. mask vertex count, ILT computation runtime) are appropriately weighted against metrics that represent RET capability (i.e. process

  8. A tunable sub-100 nm silicon nanopore array with an AAO membrane mask: reducing unwanted surface etching by introducing a PMMA interlayer.

    PubMed

    Lim, Namsoo; Pak, Yusin; Kim, Jin Tae; Hwang, Youngkyu; Lee, Ryeri; Kumaresan, Yogeenth; Myoung, NoSoung; Ko, Heung Cho; Jung, Gun Young

    2015-08-28

    Highly ordered silicon (Si) nanopores with a tunable sub-100 nm diameter were fabricated by a CF4 plasma etching process using an anodic aluminum oxide (AAO) membrane as an etching mask. To enhance the conformal contact of the AAO membrane mask to the underlying Si substrate, poly(methyl methacrylate) (PMMA) was spin-coated on top of the Si substrate prior to the transfer of the AAO membrane. The AAO membrane mask was fabricated by two-step anodization and subsequent removal of the aluminum support and the barrier layer, which was then transferred to the PMMA-coated Si substrate. Contact printing was performed on the sample with a pressure of 50 psi and a temperature of 120 °C to make a conformal contact of the AAO membrane mask to the Si substrate. The CF4 plasma etching was conducted to transfer nanopores onto the Si substrate through the PMMA interlayer. The introduced PMMA interlayer prevented unwanted surface etching of the Si substrate by eliminating the etching ions and radicals bouncing at the gap between the mask and the substrate, resulting in a smooth Si nanopore array.

  9. Mask industry assessment trend analysis: 2012

    NASA Astrophysics Data System (ADS)

    Chan, Y. David

    2012-02-01

    Microelectronics industry leaders consistently cite the cost and cycle time of mask technology and mask supply among the top critical issues for lithography. A survey was designed by SEMATECH with input from semiconductor company mask technologists and merchant mask suppliers to objectively assess the overall conditions of the mask industry. With the continued support of the industry, this year's assessment was the tenth in the current series of annual reports. This year's survey is basically the same as the 2005 through 2011 surveys. Questions are grouped into six categories: General Business Profile Information, Data Processing, Yields and Yield Loss Mechanisms, Delivery Times, Returns, and Services. Within each category is a multitude of questions that ultimately produce a detailed profile of both the business and technical status of the critical mask industry. We received data from 11 companies this year, which was a record high since the beginning of the series. The responding companies represented more than 96% of the volume shipped and about 90% of the 2011 revenue for the photomask industry. These survey reports are often used as a baseline to gain perspective on the technical and business status of the mask and microelectronics industries. They will continue to serve as a valuable reference to identify strengths and opportunities. Results can also be used to guide future investments in critical path issues.

  10. Evaluation of a new pediatric positive airway pressure mask.

    PubMed

    Kushida, Clete A; Halbower, Ann C; Kryger, Meir H; Pelayo, Rafael; Assalone, Valerie; Cardell, Chia-Yu; Huston, Stephanie; Willes, Leslee; Wimms, Alison J; Mendoza, June

    2014-09-15

    The choice and variety of pediatric masks for continuous positive airway pressure (CPAP) is limited in the US. Therefore, clinicians often prescribe modified adult masks. Until recently a mask for children aged < 7 years was not available. This study evaluated apnea-hypopnea index (AHI) equivalence and acceptability of a new pediatric CPAP mask for children aged 2-7 years (Pixi; ResMed Ltd, Sydney, Australia). Patients aged 2-7 years were enrolled and underwent in-lab baseline polysomnography (PSG) using their previous mask, then used their previous mask and the VPAP III ST-A flow generator for ≥ 10 nights at home. Thereafter, patients switched to the Pixi mask for ≥ 2 nights before returning for a PSG during PAP therapy via the Pixi mask. Patients then used the Pixi mask at home for ≥ 21 nights. Patients and their parents/guardians returned to the clinic for follow-up and provided feedback on the Pixi mask versus their previous mask. AHI with the Pixi mask was 1.1 ± 1.5/h vs 2.6 ± 5.4/h with the previous mask (p = 0.3538). Parents rated the Pixi mask positively for: restfulness of the child's sleep, trouble in getting the child to sleep, and trouble in having the child stay asleep. The Pixi mask was also rated highly for leaving fewer or no marks on the upper lip and under the child's ears, and being easy to remove. The Pixi mask is suitable for children aged 2-7 years and provides an alternative to other masks available for PAP therapy in this age group. © 2014 American Academy of Sleep Medicine.

  11. Discrimination of face gender and expression under dual-task conditions.

    PubMed

    García-Gutiérrez, Ana; Aguado, Luis; Romero-Ferreiro, Verónica; Pérez-Moreno, Elisa

    2017-02-01

    In order to test whether expression and gender can be attended to simultaneously without a cost in accuracy four experiments were carried out using a dual gender-expression task with male and female faces showing different emotional expressions that were backward masked by emotionally neutral faces. In the dual-facial condition the participants had to report both the gender and the expression of the targets. In two control conditions the participant reported either the gender or the expression of the face and indicated whether a surrounding frame was continuous or discontinuous. In Experiments 1-3, with angry and happy targets, asymmetric interference was observed. Gender discrimination, but no expression discrimination, was impaired in the dual-facial condition compared to the corresponding control. This effect was obtained with a between-subjects design in Experiment 1, with a within-subjects design in Experiment 2, and with androgynous face masks in Experiment 3. In Experiments 4a and 4b different target combinations were tested. No decrement of performance in the dual-facial task was observed for either gender or expression discrimination with fearful-disgusted (Experiment 4a) or fearful-happy faces (Experiment 4b). We conclude that the ability to attend simultaneously to gender and expression cues without a decrement in performance depends on the specific combination of expressions to be differentiated between. Happy and angry expressions are usually directed at the perceiver and command preferential attention. Under conditions of restricted viewing such as those of the present study, discrimination of these expressions is prioritized leading to impaired discrimination of other facial properties such as gender.

  12. Rapid iconic erasure without masking.

    PubMed

    Tijus, Charles Albert; Reeves, Adam

    2004-01-01

    We report on the erasure of the iconic memory of an array of 12 black letters flashed on a continuously- present white field. Erasure is accomplished by replacing the 16 ms letter array (frame 1) with a blank white frame for 16 ms (frame 2). The letter array returns in frame 3, with from one to six letters missing. Report of the missing letters is accurate without the blank white frame but is impoverished with it, as if interposing the blank erases the icon. Erasure occurs without any obvious luminance masking, 'mud splashes', pattern masking (backward, forward, or metacontrast), lateral masking, or masking by object substitution. Erasure is greatly decreased if the blank is presented one frame earlier or later. We speculate that erasure is due to a rapid reset of the icon produced by an informational mis-match.

  13. EUVL mask patterning with blanks from commercial suppliers

    NASA Astrophysics Data System (ADS)

    Yan, Pei-Yang; Zhang, Guojing; Nagpal, Rajesh; Shu, Emily Y.; Li, Chaoyang; Qu, Ping; Chen, Frederick T.

    2004-12-01

    Extreme Ultraviolet Lithography (EUVL) reflective mask blank development includes low thermal expansion material fabrication, mask substrate finishing, reflective multi-layer (ML) and capping layer deposition, buffer (optional)/absorber stack deposition, EUV specific metrology, and ML defect inspection. In the past, we have obtained blanks deposited with various layer stacks from several vendors. Some of them are not commercial suppliers. As a result, the blank and patterned mask qualities are difficult to maintain and improve. In this paper we will present the evaluation results of the EUVL mask pattering processes with the complete EUVL mask blanks supplied by the commercial blank supplier. The EUVL mask blanks used in this study consist of either quartz or ULE substrates which is a type of low thermal expansion material (LTEM), 40 pairs of molybdenum/silicon (Mo/Si) ML layer, thin ruthenium (Ru) capping layer, tantalum boron nitride (TaBN) absorber, and chrome (Cr) backside coating. No buffer layer is used. Our study includes the EUVL mask blank characterization, patterned EUVL mask characterization, and the final patterned EUVL mask flatness evaluation.

  14. Collinear masking effect in visual search is independent of perceptual salience.

    PubMed

    Jingling, Li; Lu, Yi-Hui; Cheng, Miao; Tseng, Chia-Huei

    2017-07-01

    Searching for a target in a salient region should be easier than looking for one in a nonsalient region. However, we previously discovered a contradictory phenomenon in which a local target in a salient structure was more difficult to find than one in the background. The salient structure was constructed of orientation singletons aligned to each other to form a collinear structure. In the present study, we undertake to determine whether such a masking effect was a result of salience competition between a global structure and the local target. In the first 3 experiments, we increased the salience value of the local target with the hope of adding to its competitive advantage and eventually eliminating the masking effect; nevertheless, the masking effect persisted. In an additional 2 experiments, we reduced salience of the global collinear structure by altering the orientation of the background bars and the masking effect still emerged. Our salience manipulations were validated by a controlled condition in which the global structure was grouped noncollinearly. In this case, local target salience increase (e.g., onset) or global distractor salience reduction (e.g., randomized flanking orientations) effectively removed the facilitation effect of the noncollinear structure. Our data suggest that salience competition is unlikely to explain the collinear masking effect, and other mechanisms such as contour integration, border formation, or the crowding effect may be prospective candidates for further investigation.

  15. Self-masking: Listening during vocalization. Normal hearing.

    PubMed

    Borg, Erik; Bergkvist, Christina; Gustafsson, Dan

    2009-06-01

    What underlying mechanisms are involved in the ability to talk and listen simultaneously and what role does self-masking play under conditions of hearing impairment? The purpose of the present series of studies is to describe a technique for assessment of masked thresholds during vocalization, to describe normative data for males and females, and to focus on hearing impairment. The masking effect of vocalized [a:] on narrow-band noise pulses (250-8000 Hz) was studied using the maximum vocalization method. An amplitude-modulated series of sound pulses, which sounded like a steam engine, was masked until the criterion of halving the perceived pulse rate was reached. For masking of continuous reading, a just-follow-conversation criterion was applied. Intra-session test-retest reproducibility and inter-session variability were calculated. The results showed that female voices were more efficient in masking high frequency noise bursts than male voices and more efficient in masking both a male and a female test reading. The male had to vocalize 4 dBA louder than the female to produce the same masking effect on the test reading. It is concluded that the method is relatively simple to apply and has small intra-session and fair inter-session variability. Interesting gender differences were observed.

  16. EUV mask pilot line at Intel Corporation

    NASA Astrophysics Data System (ADS)

    Stivers, Alan R.; Yan, Pei-Yang; Zhang, Guojing; Liang, Ted; Shu, Emily Y.; Tejnil, Edita; Lieberman, Barry; Nagpal, Rajesh; Hsia, Kangmin; Penn, Michael; Lo, Fu-Chang

    2004-12-01

    The introduction of extreme ultraviolet (EUV) lithography into high volume manufacturing requires the development of a new mask technology. In support of this, Intel Corporation has established a pilot line devoted to encountering and eliminating barriers to manufacturability of EUV masks. It concentrates on EUV-specific process modules and makes use of the captive standard photomask fabrication capability of Intel Corporation. The goal of the pilot line is to accelerate EUV mask development to intersect the 32nm technology node. This requires EUV mask technology to be comparable to standard photomask technology by the beginning of the silicon wafer process development phase for that technology node. The pilot line embodies Intel's strategy to lead EUV mask development in the areas of the mask patterning process, mask fabrication tools, the starting material (blanks) and the understanding of process interdependencies. The patterning process includes all steps from blank defect inspection through final pattern inspection and repair. We have specified and ordered the EUV-specific tools and most will be installed in 2004. We have worked with International Sematech and others to provide for the next generation of EUV-specific mask tools. Our process of record is run repeatedly to ensure its robustness. This primes the supply chain and collects information needed for blank improvement.

  17. Does technology acceleration equate to mask cost acceleration?

    NASA Astrophysics Data System (ADS)

    Trybula, Walter J.; Grenon, Brian J.

    2003-06-01

    The technology acceleration of the ITRS Roadmap has many implications on both the semiconductor sup-plier community and the manufacturers. INTERNATIONAL SEMATECH has revaluated the projected cost of advanced technology masks. Building on the methodology developed in 1996 for mask costs, this work provided a critical review of mask yields and factors relating to the manufacture of photolithography masks. The impact of the yields provided insight into the learning curve for leading edge mask manufac-turing. The projected mask set cost was surprising, and the ability to provide first and second year cost estimates provided additional information on technology introduction. From this information, the impact of technology acceleration can be added to the projected yields to evaluate the impact on mask costs.

  18. Individuation Training with Other-Race Faces Reduces Preschoolers' Implicit Racial Bias: A Link between Perceptual and Social Representation of Faces in Children

    ERIC Educational Resources Information Center

    Xiao, Wen S.; Fu, Genyue; Quinn, Paul C.; Qin, Jinliang; Tanaka, James W.; Pascalis, Olivier; Lee, Kang

    2015-01-01

    The present study examined whether perceptual individuation training with other-race faces could reduce preschool children's implicit racial bias. We used an "angry = outgroup" paradigm to measure Chinese children's implicit racial bias against African individuals before and after training. In Experiment 1, children between 4 and 6 years…

  19. Masks For Deposition Of Aspherical Optical Surfaces

    NASA Technical Reports Server (NTRS)

    Rogers, John R.; Martin, John D.

    1992-01-01

    Masks of improved design developed for use in fabrication of aspherical, rotationally symmetrical surfaces of mirrors, lenses, and lens molds by evaporative deposition onto rotating substrates. In deposition chamber, source and mask aligned with axis of rotation of substrate. Mask shadows source of rotating substrate. Azimuthal opening (as function of radius) in mask proportional to desired thickness (as function of radius) to which material deposited on substrate. Combination of improved masks and modern coating chambers provides optical surfaces comparable or superior to those produced by conventional polishing, computer-controlled polishing, replication from polished molds, and diamond turning, at less cost in material, labor, and capital expense.

  20. Removable pellicle for lithographic mask protection and handling

    DOEpatents

    Klebanoff, Leonard E.; Rader, Daniel J.; Hector, Scott D.; Nguyen, Khanh B.; Stulen, Richard H.

    2002-01-01

    A removable pellicle for a lithographic mask that provides active and robust particle protection, and which utilizes a traditional pellicle and two deployments of thermophoretic protection to keep particles off the mask. The removable pellicle is removably attached via a retaining structure to the mask substrate by magnetic attraction with either contacting or non-contacting magnetic capture mechanisms. The pellicle retaining structural is composed of an anchor piece secured to the mask substrate and a frame member containing a pellicle. The anchor piece and the frame member are in removable contact or non-contact by the magnetic capture or latching mechanism. In one embodiment, the frame member is retained in a floating (non-contact) relation to the anchor piece by magnetic levitation. The frame member and the anchor piece are provided with thermophoretic fins which are interdigitated to prevent particles from reaching the patterned area of the mask. Also, the anchor piece and mask are maintained at a higher temperature than the frame member and pellicle which also prevents particles from reaching the patterned mask area by thermophoresis. The pellicle can be positioned over the mask to provide particle protection during mask handling, inspection, and pumpdown, but which can be removed manually or robotically for lithographic use of the mask.

  1. Masked response priming in expert typists.

    PubMed

    Heinemann, Alexander; Kiesel, Andrea; Pohl, Carsten; Kunde, Wilfried

    2010-03-01

    In masked priming tasks responses are usually faster when prime and target require identical rather than different responses. Previous research has extensively manipulated the nature and number of response-affording stimuli. However, little is known about the constraints of masked priming regarding the nature and number of response alternatives. The present study explored the limits of masked priming in a six-choice reaction time task, where responses from different fingers of both hands were required. We studied participants that were either experts for the type of response (skilled typists) or novices. Masked primes facilitated responding to targets that required the same response, responses with a different finger of the same hand, and with a homologous finger of the other hand. These effects were modulated by expertise. The results show that masked primes facilitate responding especially for experts in the S-R mapping and with increasing similarity of primed and required response.

  2. Reticle writer for next-generation SEMI mask standard: mask handling and exposure

    NASA Astrophysics Data System (ADS)

    Ehrlich, Christian

    1998-12-01

    The world semiconductor industry is currently preparing itself for the next evolutionary step in the ongoing development of the integrated circuit, characterized by the 0.18 to 0.15 micrometer technology. The already complex engineering task for the mask tool makers is furthermore complicated by the introduction of the new SEMI reticle standard with a 230 mm by 230 mm large and 9 mm thick quartz glass blank that will have a weight of more than one kilogram. The production of these advanced masks is already identified as a key enabling technology which will stretch the capabilities of the manufacturing process, and its equipment, to the limit. The mask making e-beam system Leica ZBA320, capable of exposing a 230 mm reticle and featuring the variable shaped beam approach with a 20 kV accelerating voltage has been introduced recently. Now the first results of e-beam exposures with this new type of mask writer are presented. Enhancements form the previous generation system include improved deflection systems, stage metrology, pattern data handling, and an address grid down to 10 nanometers. This system's specified performance enables it to produce reticles designed to support semiconductor fabrication utilizing 180 nanometer design rules, and beyond, with high accuracy and productivity.

  3. Comodulation masking release in an off-frequency masking paradigm.

    PubMed

    Grzeschik, Ramona; Lübken, Björn; Verhey, Jesko L

    2015-08-01

    Detection threshold of a sinusoidal signal masked by a broadband masker is lower when on- and off-frequency masker components have a correlated envelope, compared to a condition in which these masker components have different envelopes. This effect is commonly referred to as comodulation masking release (CMR). The present study investigated if there is a CMR in the absence of a masker component at the signal frequency, i.e., in an off-frequency masking paradigm. Thresholds were measured for a 500-Hz signal in the presence of a broadband masker with a spectral notch at the signal frequency. Thresholds were significantly lower for a (co-)modulated than for an unmodulated masker for all notch widths up to 400 Hz. An additional experiment showed that the particularly large CMR for the no-notch condition was due to the way the modulated masker was generated. No CMR was measured when the notched-noise masker was replaced by a pair of narrowband noises. The addition of more remote masker bands resulted in a CMR of about 3-4 dB. The notched-noise data were predicted on the basis of a modulation-filterbank model. The predictions of the narrowband noise conditions indicated that all mechanisms underlying CMR might still not be fully understood.

  4. 1D design style implications for mask making and CEBL

    NASA Astrophysics Data System (ADS)

    Smayling, Michael C.

    2013-09-01

    At advanced nodes, CMOS logic is being designed in a highly regular design style because of the resolution limitations of optical lithography equipment. Logic and memory layouts using 1D Gridded Design Rules (GDR) have been demonstrated to nodes beyond 12nm.[1-4] Smaller nodes will require the same regular layout style but with multiple patterning for critical layers. One of the significant advantages of 1D GDR is the ease of splitting layouts into lines and cuts. A lines and cuts approach has been used to achieve good pattern fidelity and process margin to below 12nm.[4] Line scaling with excellent line-edge roughness (LER) has been demonstrated with self-aligned spacer processing.[5] This change in design style has important implications for mask making: • The complexity of the masks will be greatly reduced from what would be required for 2D designs with very complex OPC or inverse lithography corrections. • The number of masks will initially increase, as for conventional multiple patterning. But in the case of 1D design, there are future options for mask count reduction. • The line masks will remain simple, with little or no OPC, at pitches (1x) above 80nm. This provides an excellent opportunity for continual improvement of line CD and LER. The line pattern will be processed through a self-aligned pitch division sequence to divide pitch by 2 or by 4. • The cut masks can be done with "simple OPC" as demonstrated to beyond 12nm.[6] Multiple simple cut masks may be required at advanced nodes. "Coloring" has been demonstrated to below 12nm for two colors and to 8nm for three colors. • Cut/hole masks will eventually be replaced by e-beam direct write using complementary e-beam lithography (CEBL).[7-11] This transition is gated by the availability of multiple column e-beam systems with throughput adequate for high- volume manufacturing. A brief description of 1D and 2D design styles will be presented, followed by examples of 1D layouts. Mask complexity for 1

  5. Jig Aligns Shadow Mask On CCD

    NASA Technical Reports Server (NTRS)

    Matus, Carlos V.

    1989-01-01

    Alignment viewed through microscope. Alignment jig positions shadow mask on charge-coupled device (CCD) so metal film deposited on it precisely. Allows CCD package to be inserted and removed without disturbing alignment of mask. Holds CCD packages securely and isolates it electrostatically while providing electrical contact to each of its pins. When alignment jig assembled with CCD, used to move mask under micrometer control.

  6. Masked Hypertension is Associated With Cognitive Decline in Geriatric Age-Geriatric MASked Hypertension and Cognition (G-MASH-cog) Study.

    PubMed

    Esme, Mert; Yavuz, Burcu Balam; Yavuz, Bunyamin; Asil, Serkan; Tuna Dogrul, Rana; Sumer, Fatih; Kilic, Mustafa Kemal; Kizilarslanoglu, Muhammet Cemal; Varan, Hacer Dogan; Sagir, Aykut; Balci, Cafer; Halil, Meltem; Cankurtaran, Mustafa

    2018-01-16

    Masked hypertension is described as high ambulatory blood pressure measurements (ABPM) where office blood pressure measurements are normal. Effect of hypertension on cognitive functions is well known. However, the effect of masked hypertension on cognitive functions is unclear. The aim of this study is to examine the relationship between masked hypertension and cognitive functions. One hundred-two normotensive patients admitted to the Geriatric Medicine outpatient clinic were included. Exclusion criteria were hypertension, dementia, major depression, and usage of antihypertensive medication. All patients underwent ABPM procedures and average daytime blood pressure, mean blood pressure at night and the 24-hour average blood pressure measurements were recorded. Comprehensive geriatric assessment tests and neuropsychological tests were administered. The diagnosis of masked hypertension was based on the definitions in the 2013 guideline of the European Society of Cardiology. Forty-four patients (43%) were diagnosed with masked hypertension. Patients with masked hypertension had significantly lower scores on Mini-Mental State Examination (MMSE) test, Quick Mild Cognitive Impairment Test (QMCI), and Categorical Fluency Test than the normotensive patients (p = .011; p = .046; and p = .004; respectively). Montreal Cognitive Assessment Scale test score was lower in masked hypertension, although this was not statistically significant. This study may indicate that geriatric patients with masked hypertension, compared to normotensive patients have decreased cognitive functions. Masked hypertension should be kept in mind while assessing older adults. When masked hypertension is detected, cognitive assessment is essential to diagnose possible cognitive dysfunction at early stage. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Informational masking of speech in children: Effects of ipsilateral and contralateral distracters

    NASA Astrophysics Data System (ADS)

    Wightman, Frederic L.; Kistler, Doris J.

    2005-11-01

    Using a closed-set speech recognition paradigm thought to be heavily influenced by informational masking, auditory selective attention was measured in 38 children (ages 4-16 years) and 8 adults (ages 20-30 years). The task required attention to a monaural target speech message that was presented with a time-synchronized distracter message in the same ear. In some conditions a second distracter message or a speech-shaped noise was presented to the other ear. Compared to adults, children required higher target/distracter ratios to reach comparable performance levels, reflecting more informational masking in these listeners. Informational masking in most conditions was confirmed by the fact that a large proportion of the errors made by the listeners were contained in the distracter message(s). There was a monotonic age effect, such that even the children in the oldest age group (13.6-16 years) demonstrated poorer performance than adults. For both children and adults, presentation of an additional distracter in the contralateral ear significantly reduced performance, even when the distracter messages were produced by a talker of different sex than the target talker. The results are consistent with earlier reports from pure-tone masking studies that informational masking effects are much larger in children than in adults.

  8. Mask leak increases and minute ventilation decreases when chest compressions are added to bag ventilation in a neonatal manikin model.

    PubMed

    Tracy, Mark B; Shah, Dharmesh; Hinder, Murray; Klimek, Jan; Marceau, James; Wright, Audrey

    2014-05-01

    To determine changes in respiratory mechanics when chest compressions are added to mask ventilation, as recommended by the International Liaison Committee on Resuscitation (ILCOR) guidelines for newborn infants. Using a Laerdal Advanced Life Support leak-free baby manikin and a 240-mL self-inflating bag, 58 neonatal staff members were randomly paired to provide mask ventilation, followed by mask ventilation with chest compressions with a 1:3 ratio, for two minutes each. A Florian respiratory function monitor was used to measure respiratory mechanics, including mask leak. The addition of chest compressions to mask ventilation led to a significant reduction in inflation rate, from 63.9 to 32.9 breaths per minute (p < 0.0001), mean airway pressure reduced from 7.6 to 4.9 cm H2 O (p < 0.001), minute ventilation reduced from 770 to 451 mL/kg/min (p < 0.0001), and there was a significant increase in paired mask leak of 6.8% (p < 0.0001). Adding chest compressions to mask ventilation, in accordance with the ILCOR guidelines, in a manikin model is associated with a significant reduction in delivered ventilation and increase in mask leak. If similar findings occur in human infants needing an escalation in resuscitation, there is a potential risk of either delay in recovery or inadequate response to resuscitation. ©2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  9. Evaluation of a New Pediatric Positive Airway Pressure Mask

    PubMed Central

    Kushida, Clete A.; Halbower, Ann C.; Kryger, Meir H.; Pelayo, Rafael; Assalone, Valerie; Cardell, Chia-Yu; Huston, Stephanie; Willes, Leslee; Wimms, Alison J.; Mendoza, June

    2014-01-01

    Study Objectives: The choice and variety of pediatric masks for continuous positive airway pressure (CPAP) is limited in the US. Therefore, clinicians often prescribe modified adult masks. Until recently a mask for children aged < 7 years was not available. This study evaluated apnea-hypopnea index (AHI) equivalence and acceptability of a new pediatric CPAP mask for children aged 2-7 years (Pixi; ResMed Ltd, Sydney, Australia). Methods: Patients aged 2-7 years were enrolled and underwent in-lab baseline polysomnography (PSG) using their previous mask, then used their previous mask and the VPAP III ST-A flow generator for ≥ 10 nights at home. Thereafter, patients switched to the Pixi mask for ≥ 2 nights before returning for a PSG during PAP therapy via the Pixi mask. Patients then used the Pixi mask at home for ≥ 21 nights. Patients and their parents/guardians returned to the clinic for follow-up and provided feedback on the Pixi mask versus their previous mask. Results: AHI with the Pixi mask was 1.1 ± 1.5/h vs 2.6 ± 5.4/h with the previous mask (p = 0.3538). Parents rated the Pixi mask positively for: restfulness of the child's sleep, trouble in getting the child to sleep, and trouble in having the child stay asleep. The Pixi mask was also rated highly for leaving fewer or no marks on the upper lip and under the child's ears, and being easy to remove. Conclusions: The Pixi mask is suitable for children aged 2-7 years and provides an alternative to other masks available for PAP therapy in this age group. Citation: Kushida CA, Halbower AC, Kryger MH, Pelayo R, Assalone V, Cardell CY, Huston S, Willes L, Wimms AJ, Mendoza J. Evaluation of a new pediatric positive airway pressure mask. J Clin Sleep Med 2014;10(9):979-984. PMID:25142768

  10. Analytical treatment of the deformation behavior of EUVL masks during electrostatic chucking

    NASA Astrophysics Data System (ADS)

    Brandstetter, Gerd; Govindjee, Sanjay

    2012-03-01

    A new analytical approach is presented to predict mask deformation during electro-static chucking in next generation extreme-ultraviolet-lithography (EUVL). Given an arbitrary profile measurement of the mask and chuck non-flatness, this method has been developed as an alternative to time-consuming finite element simulations for overlay error correction algorithms. We consider the feature transfer of each harmonic component in the profile shapes via linear elasticity theory and demonstrate analytically how high spatial frequencies are filtered. The method is compared to presumably more accurate finite element simulations and has been tested successfully in an overlay error compensation experiment, where the residual error y-component could be reduced by a factor 2. As a side outcome, the formulation provides a tool to estimate the critical pin-size and -pitch such that the distortion on the mask front-side remains within given tolerances. We find for a numerical example that pin-pitches of less than 5 mm will result in a mask pattern-distortion of less than 1 nm if the chucking pressure is below 30 kPa.

  11. Face in profile view reduces perceived facial expression intensity: an eye-tracking study.

    PubMed

    Guo, Kun; Shaw, Heather

    2015-02-01

    Recent studies measuring the facial expressions of emotion have focused primarily on the perception of frontal face images. As we frequently encounter expressive faces from different viewing angles, having a mechanism which allows invariant expression perception would be advantageous to our social interactions. Although a couple of studies have indicated comparable expression categorization accuracy across viewpoints, it is unknown how perceived expression intensity and associated gaze behaviour change across viewing angles. Differences could arise because diagnostic cues from local facial features for decoding expressions could vary with viewpoints. Here we manipulated orientation of faces (frontal, mid-profile, and profile view) displaying six common facial expressions of emotion, and measured participants' expression categorization accuracy, perceived expression intensity and associated gaze patterns. In comparison with frontal faces, profile faces slightly reduced identification rates for disgust and sad expressions, but significantly decreased perceived intensity for all tested expressions. Although quantitatively viewpoint had expression-specific influence on the proportion of fixations directed at local facial features, the qualitative gaze distribution within facial features (e.g., the eyes tended to attract the highest proportion of fixations, followed by the nose and then the mouth region) was independent of viewpoint and expression type. Our results suggest that the viewpoint-invariant facial expression processing is categorical perception, which could be linked to a viewpoint-invariant holistic gaze strategy for extracting expressive facial cues. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Event-related potentials to structural familiar face incongruity processing.

    PubMed

    Jemel, B; George, N; Olivares, E; Fiori, N; Renault, B

    1999-07-01

    Thirty scalp sites were used to investigate the specific topography of the event-related potentials (ERPs) related to face associative priming when masked eyes of familiar faces were completed with either the proper features or incongruent ones. The enhanced negativity of N210 and N350, due to structural incongruity of faces, have a "category specific" inferotemporal localization on the scalp. Additional analyses support the existence of multiple ERP features within the temporal interval typically associated with N400 (N350 and N380), involving occipitotemporal and centroparietal areas. Seven reliable dipole locations have been evidenced using the brain electrical source analysis algorithm. Some of these localizations (fusiform, parahippocampal) are already known to be involved in face recognition, the other ones being related to general cognitive processes related to the task's demand. Because of their specific topography, the observed effects suggest that the face structural congruency process might involve early specialized neocortical areas in parallel with cortical memory circuits in the integration of perceptual and cognitive face processing.

  13. Place specificity of monopolar and tripolar stimuli in cochlear implants: the influence of residual masking.

    PubMed

    Fielden, Claire A; Kluk, Karolina; McKay, Colette M

    2013-06-01

    This experiment investigated whether place specificity of neural activity evoked by cochlear implant stimulation is improved in tripolar compared to monopolar mode using a forward masking protocol addressing some limitations of previous methods of measurement and analysis. The amount of residual masking (masking remaining at long masker-probe delays) was also measured, and its potential influence on the specificity measures was evaluated. The masker stimulus comprised equally loud interleaved mono- or tripolar stimulation on two electrodes equidistant from a central probe electrode in an apical and basal direction, reducing the influence of off-site listening. The effect of masker-probe distance on the threshold shift of the tripolar probe was analyzed to derive a measure of place specificity. On average, tripolar maskers were more place specific than monopolar maskers, although the mean effect was small. There was no significant effect of masker level on specificity or on the differences observed between modes. The mean influence of residual masking on normalized masking functions was similar for the two modes and, therefore, did not influence the comparison of specificity between the modes. However, variability in amount of residual masking was observed between subjects, and therefore should be considered in forward masking studies that compare place specificity across subjects.

  14. Ipsilateral masking between acoustic and electric stimulations.

    PubMed

    Lin, Payton; Turner, Christopher W; Gantz, Bruce J; Djalilian, Hamid R; Zeng, Fan-Gang

    2011-08-01

    Residual acoustic hearing can be preserved in the same ear following cochlear implantation with minimally traumatic surgical techniques and short-electrode arrays. The combined electric-acoustic stimulation significantly improves cochlear implant performance, particularly speech recognition in noise. The present study measures simultaneous masking by electric pulses on acoustic pure tones, or vice versa, to investigate electric-acoustic interactions and their underlying psychophysical mechanisms. Six subjects, with acoustic hearing preserved at low frequencies in their implanted ear, participated in the study. One subject had a fully inserted 24 mm Nucleus Freedom array and five subjects had Iowa/Nucleus hybrid implants that were only 10 mm in length. Electric masking data of the long-electrode subject showed that stimulation from the most apical electrodes produced threshold elevations over 10 dB for 500, 625, and 750 Hz probe tones, but no elevation for 125 and 250 Hz tones. On the contrary, electric stimulation did not produce any electric masking in the short-electrode subjects. In the acoustic masking experiment, 125-750 Hz pure tones were used to acoustically mask electric stimulation. The acoustic masking results showed that, independent of pure tone frequency, both long- and short-electrode subjects showed threshold elevations at apical and basal electrodes. The present results can be interpreted in terms of underlying physiological mechanisms related to either place-dependent peripheral masking or place-independent central masking.

  15. Application of multi-tone mask technology in photolithographic fabrication of color filter components in LCD

    NASA Astrophysics Data System (ADS)

    Takada, Yoshihiro; Fukui, Matoko; Sai, Tsunehiro

    2008-11-01

    Recent progresses in the photoresists and photolithography for LCD industry applications have been primarily driven by the following two factors: advancement in the material performances (high resolution, high contrast ratio, low dielectric constant) for higher display quality, and cost reduction in the fabrication process. Along with crucial demand for cost competitiveness by improving production efficiency, environmental consciousness has been a major priority at fabrication process design to minimize the amount of waste produced. Having said the above, integration of two or more fabrication processes into a single process by using multi-tone mask technology has been the interest of research, due to its obvious advantage of reducing fabrication processes and cost. For example, multi-tone mask technology application has been widely employed on the TFT side to reduce the different types of photomasks being used. Similar trend has been employed on the CF side as well, where application of multi-tone mask technology is being investigated to integrate fabrication of multiple CF micro-components into a single process. In this presentation, we demonstrate a new approach of fabricating photospacer and peripheral CF components (MVA protrusion, sub-photospacers) in a single integrated process through multi-tone mask technology.

  16. SMIF capability at Intel Mask Operation improves yield

    NASA Astrophysics Data System (ADS)

    Dam, Thuc H.; Pekny, Matt; Millino, Jim; Luu, Gibson; Melwani, Nitesh; Venkatramani, Aparna; Tavassoli, Malahat

    2003-08-01

    At Intel Mask Operations (IMO), Standard Mechanical Interface (SMIF) processing has been employed to reduce environmental particle contamination from manual handling-related activities. SMIF handling entailed the utilization of automated robotic transfers of photoblanks/reticles between SMIF pods, whereas conventional handling utilized manual pick transfers of masks between SMIF pods with intermediate storage in Toppan compacts. The SMIF-enabling units in IMO's process line included: (1) coater, (2) exposure, (3) developer, (4) dry etcher, and (5) inspection. Each unit is equipped with automated I/O port, environmentally enclosed processing chamber, and SMIF pods. Yield metrics were utilized to demonstrate the effectiveness and advantages of SMIF processing compared to manual processing. The areas focused in this paper were blank resist coating, binary front-end reticle processing and 2nd level PSM reticle processing. Results obtained from the investigation showed yield improvements in these areas.

  17. Overlay improvement by exposure map based mask registration optimization

    NASA Astrophysics Data System (ADS)

    Shi, Irene; Guo, Eric; Chen, Ming; Lu, Max; Li, Gordon; Li, Rivan; Tian, Eric

    2015-03-01

    Along with the increased miniaturization of semiconductor electronic devices, the design rules of advanced semiconductor devices shrink dramatically. [1] One of the main challenges of lithography step is the layer-to-layer overlay control. Furthermore, DPT (Double Patterning Technology) has been adapted for the advanced technology node like 28nm and 14nm, corresponding overlay budget becomes even tighter. [2][3] After the in-die mask registration (pattern placement) measurement is introduced, with the model analysis of a KLA SOV (sources of variation) tool, it's observed that registration difference between masks is a significant error source of wafer layer-to-layer overlay at 28nm process. [4][5] Mask registration optimization would highly improve wafer overlay performance accordingly. It was reported that a laser based registration control (RegC) process could be applied after the pattern generation or after pellicle mounting and allowed fine tuning of the mask registration. [6] In this paper we propose a novel method of mask registration correction, which can be applied before mask writing based on mask exposure map, considering the factors of mask chip layout, writing sequence, and pattern density distribution. Our experiment data show if pattern density on the mask keeps at a low level, in-die mask registration residue error in 3sigma could be always under 5nm whatever blank type and related writer POSCOR (position correction) file was applied; it proves random error induced by material or equipment would occupy relatively fixed error budget as an error source of mask registration. On the real production, comparing the mask registration difference through critical production layers, it could be revealed that registration residue error of line space layers with higher pattern density is always much larger than the one of contact hole layers with lower pattern density. Additionally, the mask registration difference between layers with similar pattern density

  18. Evaluation of a native vegetation masking technique

    NASA Technical Reports Server (NTRS)

    Kinsler, M. C.

    1984-01-01

    A crop masking technique based on Ashburn's vegetative index (AVI) was used to evaluate native vegetation as an indicator of crop moisture condition. A mask of the range areas (native vegetation) was generated for each of thirteen Great Plains LANDSAT MSS sample segments. These masks were compared to the digitized ground truth and accuracies were computed. An analysis of the types of errors indicates a consistency in errors among the segments. The mask represents a simple quick-look technique for evaluating vegetative cover.

  19. Inverse lithography using sparse mask representations

    NASA Astrophysics Data System (ADS)

    Ionescu, Radu C.; Hurley, Paul; Apostol, Stefan

    2015-03-01

    We present a novel optimisation algorithm for inverse lithography, based on optimization of the mask derivative, a domain inherently sparse, and for rectilinear polygons, invertible. The method is first developed assuming a point light source, and then extended to general incoherent sources. What results is a fast algorithm, producing manufacturable masks (the search space is constrained to rectilinear polygons), and flexible (specific constraints such as minimal line widths can be imposed). One inherent trick is to treat polygons as continuous entities, thus making aerial image calculation extremely fast and accurate. Requirements for mask manufacturability can be integrated in the optimization without too much added complexity. We also explain how to extend the scheme for phase-changing mask optimization.

  20. Is masked priming modulated by memory load? A test of the automaticity of masked identity priming in lexical decision.

    PubMed

    Perea, Manuel; Marcet, Ana; Lozano, Mario; Gomez, Pablo

    2018-05-29

    One of the key assumptions of the masked priming lexical decision task (LDT) is that primes are processed without requiring attentional resources. Here, we tested this assumption by presenting a dual-task manipulation to increase memory load and measure the change in masked identity priming on the targets in the LDT. If masked priming does not require attentional resources, increased memory load should have no influence on the magnitude of the observed identity priming effects. We conducted two LDT experiments, using a within-subjects design, to investigate the effect of memory load (via a concurrent matching task Experiment 1 and a concurrent search task in Experiment 2) on masked identity priming. Results showed that the magnitude of masked identity priming on word targets was remarkably similar under high and low memory load. Thus, these experiments provide empirical evidence for the automaticity assumption of masked identity priming in the LDT.

  1. Associative and repetition priming with the repeated masked prime technique: no priming found.

    PubMed

    Avons, S E; Russo, Riccardo; Cinel, Caterina; Verolini, Veronica; Glynn, Kevin; McDonald, Rebecca; Cameron, Marie

    2009-01-01

    Wentura and Frings (2005) reported evidence of subliminal categorical priming on a lexical decision task, using a new method of visual masking in which the prime string consisted of the prime word flanked by random consonants and random letter masks alternated with the prime string on successive refresh cycles. We investigated associative and repetition priming on lexical decision, using the same method of visual masking. Three experiments failed to show any evidence of associative priming, (1) when the prime string was fixed at 10 characters (three to six flanking letters) and (2) when the number of flanking letters were reduced or absent. In all cases, prime detection was at chance level. Strong associative priming was observed with visible unmasked primes, but the addition of flanking letters restricted priming even though prime detection was still high. With repetition priming, no priming effects were found with the repeated masked technique, and prime detection was poor but just above chance levels. We conclude that with repeated masked primes, there is effective visual masking but that associative priming and repetition priming do not occur with experiment-unique prime-target pairs. Explanations for this apparent discrepancy across priming paradigms are discussed. The priming stimuli and prime-target pairs used in this study may be downloaded as supplemental materials from mc.psychonomic-journals.org/content/supplemental.

  2. Cost-effective masks for deep x-ray lithography

    NASA Astrophysics Data System (ADS)

    Scheunemann, Heinz-Ulrich; Loechel, Bernd; Jian, Linke; Schondelmaier, Daniel; Desta, Yohannes M.; Goettert, Jost

    2003-04-01

    The production of X-ray masks is one of the key techniques for X-ray lithography and the LIGA process. Different ways for the fabrication of X-ray masks has been established. Very sophisticated, difficult and expensive procedures are required to produce high precision and high quality X-ray masks. In order to minimize the cost of an X-ray mask, the mask blank must be inexpensive and readily available. The steps involved in the fabrication process must also be minimal. In the past, thin membranes made of titanium, silicon carbide, silicon nitride (2-5μm) or thick beryllium substrates (500μm) have been used as mask blanks. Thin titanium and silicon compounds have very high transparency for X-rays; therefore, these materials are predestined for use as mask membrane material. However, the handling and fabrication of thin membranes is very difficult, thus expensive. Beryllium is highly transparent to X-rays, but the processing and use of beryllium is risky due to potential toxicity. During the past few years graphite based X-ray masks have been in use at various research centers, but the sidewall quality of the generated resist patterns is in the range of 200-300 nm Ra. We used polished graphite to improve the sidewall roughness, but polished graphite causes other problems in the fabrication of X-ray masks. This paper describes the advantages associated with the use of polished graphite as mask blank as well as the fabrication process for this low cost X-ray mask. Alternative membrane materials will also be discussed.

  3. Effect of Masked Regions on Weak-lensing Statistics

    NASA Astrophysics Data System (ADS)

    Shirasaki, Masato; Yoshida, Naoki; Hamana, Takashi

    2013-09-01

    Sky masking is unavoidable in wide-field weak-lensing observations. We study how masks affect the measurement of statistics of matter distribution probed by weak gravitational lensing. We first use 1000 cosmological ray-tracing simulations to examine in detail the impact of masked regions on the weak-lensing Minkowski Functionals (MFs). We consider actual sky masks used for a Subaru Suprime-Cam imaging survey. The masks increase the variance of the convergence field and the expected values of the MFs are biased. The bias then compromises the non-Gaussian signals induced by the gravitational growth of structure. We then explore how masks affect cosmological parameter estimation. We calculate the cumulative signal-to-noise ratio (S/N) for masked maps to study the information content of lensing MFs. We show that the degradation of S/N for masked maps is mainly determined by the effective survey area. We also perform simple χ2 analysis to show the impact of lensing MF bias due to masked regions. Finally, we compare ray-tracing simulations with data from a Subaru 2 deg2 survey in order to address if the observed lensing MFs are consistent with those of the standard cosmology. The resulting χ2/n dof = 29.6/30 for three combined MFs, obtained with the mask effects taken into account, suggests that the observational data are indeed consistent with the standard ΛCDM model. We conclude that the lensing MFs are a powerful probe of cosmology only if mask effects are correctly taken into account.

  4. EFFECT OF MASKED REGIONS ON WEAK-LENSING STATISTICS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shirasaki, Masato; Yoshida, Naoki; Hamana, Takashi, E-mail: masato.shirasaki@utap.phys.s.u-tokyo.ac.jp

    2013-09-10

    Sky masking is unavoidable in wide-field weak-lensing observations. We study how masks affect the measurement of statistics of matter distribution probed by weak gravitational lensing. We first use 1000 cosmological ray-tracing simulations to examine in detail the impact of masked regions on the weak-lensing Minkowski Functionals (MFs). We consider actual sky masks used for a Subaru Suprime-Cam imaging survey. The masks increase the variance of the convergence field and the expected values of the MFs are biased. The bias then compromises the non-Gaussian signals induced by the gravitational growth of structure. We then explore how masks affect cosmological parameter estimation.more » We calculate the cumulative signal-to-noise ratio (S/N) for masked maps to study the information content of lensing MFs. We show that the degradation of S/N for masked maps is mainly determined by the effective survey area. We also perform simple {chi}{sup 2} analysis to show the impact of lensing MF bias due to masked regions. Finally, we compare ray-tracing simulations with data from a Subaru 2 deg{sup 2} survey in order to address if the observed lensing MFs are consistent with those of the standard cosmology. The resulting {chi}{sup 2}/n{sub dof} = 29.6/30 for three combined MFs, obtained with the mask effects taken into account, suggests that the observational data are indeed consistent with the standard {Lambda}CDM model. We conclude that the lensing MFs are a powerful probe of cosmology only if mask effects are correctly taken into account.« less

  5. Mask technology for EUV lithography

    NASA Astrophysics Data System (ADS)

    Bujak, M.; Burkhart, Scott C.; Cerjan, Charles J.; Kearney, Patrick A.; Moore, Craig E.; Prisbrey, Shon T.; Sweeney, Donald W.; Tong, William M.; Vernon, Stephen P.; Walton, Christopher C.; Warrick, Abbie L.; Weber, Frank J.; Wedowski, Marco; Wilhelmsen, Karl C.; Bokor, Jeffrey; Jeong, Sungho; Cardinale, Gregory F.; Ray-Chaudhuri, Avijit K.; Stivers, Alan R.; Tejnil, Edita; Yan, Pei-yang; Hector, Scott D.; Nguyen, Khanh B.

    1999-04-01

    Extreme UV Lithography (EUVL) is one of the leading candidates for the next generation lithography, which will decrease critical feature size to below 100 nm within 5 years. EUVL uses 10-14 nm light as envisioned by the EUV Limited Liability Company, a consortium formed by Intel and supported by Motorola and AMD to perform R and D work at three national laboratories. Much work has already taken place, with the first prototypical cameras operational at 13.4 nm using low energy laser plasma EUV light sources to investigate issues including the source, camera, electro- mechanical and system issues, photoresists, and of course the masks. EUV lithograph masks are fundamentally different than conventional photolithographic masks as they are reflective instead of transmissive. EUV light at 13.4 nm is rapidly absorbed by most materials, thus all light transmission within the EUVL system from source to silicon wafer, including EUV reflected from the mask, is performed by multilayer mirrors in vacuum.

  6. Homophone Dominance Modulates the Phonemic-Masking Effect.

    ERIC Educational Resources Information Center

    Berent, Iris; Van Orden, Guy C.

    2000-01-01

    Finds (1) positive phonemic-masking effects occurred for dominant homophones; (2) null phonemic-masking effects occurred for subordinate homophones; and (3) subordinate homophones were much more likely to be falsely identified as their dominant mate. Suggests the source of these null phonemic-masking is itself a phonology effect. Concludes…

  7. 21 CFR 868.5560 - Gas mask head strap.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gas mask head strap. 868.5560 Section 868.5560...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5560 Gas mask head strap. (a) Identification. A gas mask head strap is a device used to hold an anesthetic gas mask in position on a patient's...

  8. 42 CFR 84.75 - Half-mask facepieces, full facepieces, mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.75 Half-mask facepieces, full... which shall not reduce the respiratory protective qualities of the apparatus. (c) Apparatus with...

  9. 42 CFR 84.75 - Half-mask facepieces, full facepieces, mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.75 Half-mask facepieces, full... which shall not reduce the respiratory protective qualities of the apparatus. (c) Apparatus with...

  10. 42 CFR 84.75 - Half-mask facepieces, full facepieces, mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.75 Half-mask facepieces, full... which shall not reduce the respiratory protective qualities of the apparatus. (c) Apparatus with...

  11. 42 CFR 84.75 - Half-mask facepieces, full facepieces, mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.75 Half-mask facepieces, full... which shall not reduce the respiratory protective qualities of the apparatus. (c) Apparatus with...

  12. 42 CFR 84.75 - Half-mask facepieces, full facepieces, mouthpieces; fit; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.75 Half-mask facepieces, full... which shall not reduce the respiratory protective qualities of the apparatus. (c) Apparatus with...

  13. Effect of SPM-based cleaning POR on EUV mask performance

    NASA Astrophysics Data System (ADS)

    Choi, Jaehyuck; Lee, Han-shin; Yoon, Jinsang; Shimomura, Takeya; Friz, Alex; Montgomery, Cecilia; Ma, Andy; Goodwin, Frank; Kang, Daehyuk; Chung, Paul; Shin, Inkyun; Cho, H.

    2011-11-01

    EUV masks include many different layers of various materials rarely used in optical masks, and each layer of material has a particular role in enhancing the performance of EUV lithography. Therefore, it is crucial to understand how the mask quality and patterning performance can change during mask fabrication, EUV exposure, maintenance cleaning, shipping, or storage. The fact that a pellicle is not used to protect the mask surface in EUV lithography suggests that EUV masks may have to undergo more cleaning cycles during their lifetime. More frequent cleaning, combined with the adoption of new materials for EUV masks, necessitates that mask manufacturers closely examine the performance change of EUV masks during cleaning process. We have investigated EUV mask quality and patterning performance during 30 cycles of Samsung's EUV mask SPM-based cleaning and 20 cycles of SEMATECH ADT exposure. We have observed that the quality and patterning performance of EUV masks does not significantly change during these processes except mask pattern CD change. To resolve this issue, we have developed an acid-free cleaning POR and substantially improved EUV mask film loss compared to the SPM-based cleaning POR.

  14. Combining Simultaneous with Temporal Masking

    ERIC Educational Resources Information Center

    Hermens, Frouke; Herzog, Michael H.; Francis, Gregory

    2009-01-01

    Simultaneous and temporal masking are two frequently used techniques in psychology and vision science. Although there are many studies and theories related to each masking technique, there are no systematic investigations of their mutual relationship, even though both techniques are often applied together. Here, the authors show that temporal…

  15. Understanding EUV mask blank surface roughness induced LWR and associated roughness requirement

    NASA Astrophysics Data System (ADS)

    Yan, Pei-Yang; Zhang, Guojing; Gullikson, Eric M.; Goldberg, Ken A.; Benk, Markus P.

    2015-03-01

    Extreme ultraviolet lithography (EUVL) mask multi-layer (ML) blank surface roughness specification historically comes from blank defect inspection tool requirement. Later, new concerns on ML surface roughness induced wafer pattern line width roughness (LWR) arise. In this paper, we have studied wafer level pattern LWR as a function of EUVL mask surface roughness via High-NA Actinic Reticle Review Tool. We found that the blank surface roughness induced LWR at current blank roughness level is in the order of 0.5nm 3σ for NA=0.42 at the best focus. At defocus of ±40nm, the corresponding LWR will be 0.2nm higher. Further reducing EUVL mask blank surface roughness will increase the blank cost with limited benefit in improving the pattern LWR, provided that the intrinsic resist LWR is in the order of 1nm and above.

  16. Masked mycotoxins: A review

    PubMed Central

    Berthiller, Franz; Crews, Colin; Dall'Asta, Chiara; Saeger, Sarah De; Haesaert, Geert; Karlovsky, Petr; Oswald, Isabelle P; Seefelder, Walburga; Speijers, Gerrit; Stroka, Joerg

    2013-01-01

    The aim of this review is to give a comprehensive overview of the current knowledge on plant metabolites of mycotoxins, also called masked mycotoxins. Mycotoxins are secondary fungal metabolites, toxic to human and animals. Toxigenic fungi often grow on edible plants, thus contaminating food and feed. Plants, as living organisms, can alter the chemical structure of mycotoxins as part of their defence against xenobiotics. The extractable conjugated or non-extractable bound mycotoxins formed remain present in the plant tissue but are currently neither routinely screened for in food nor regulated by legislation, thus they may be considered masked. Fusarium mycotoxins (deoxynivalenol, zearalenone, fumonisins, nivalenol, fusarenon-X, T-2 toxin, HT-2 toxin, fusaric acid) are prone to metabolisation or binding by plants, but transformation of other mycotoxins by plants (ochratoxin A, patulin, destruxins) has also been described. Toxicological data are scarce, but several studies highlight the potential threat to consumer safety from these substances. In particular, the possible hydrolysis of masked mycotoxins back to their toxic parents during mammalian digestion raises concerns. Dedicated chapters of this article address plant metabolism as well as the occurrence of masked mycotoxins in food, analytical aspects for their determination, toxicology and their impact on stakeholders. PMID:23047235

  17. 21 CFR 868.5550 - Anesthetic gas mask.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthetic gas mask. 868.5550 Section 868.5550...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5550 Anesthetic gas mask. (a) Identification. An anesthetic gas mask is a device, usually made of conductive rubber, that is positioned over a...

  18. 21 CFR 868.5550 - Anesthetic gas mask.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Anesthetic gas mask. 868.5550 Section 868.5550...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5550 Anesthetic gas mask. (a) Identification. An anesthetic gas mask is a device, usually made of conductive rubber, that is positioned over a...

  19. 21 CFR 868.5550 - Anesthetic gas mask.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Anesthetic gas mask. 868.5550 Section 868.5550...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5550 Anesthetic gas mask. (a) Identification. An anesthetic gas mask is a device, usually made of conductive rubber, that is positioned over a...

  20. 21 CFR 868.5550 - Anesthetic gas mask.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Anesthetic gas mask. 868.5550 Section 868.5550...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5550 Anesthetic gas mask. (a) Identification. An anesthetic gas mask is a device, usually made of conductive rubber, that is positioned over a...