Doucet, Barbara M.; Griffin, Lisa
2014-01-01
Introduction The optimal parameters of neuromuscular electrical stimulation (NMES) for recovery of hand function following stroke are not known. This clinical pilot study examined whether higher or lower frequencies are more effective for improving fine motor control of the hand in a chronic post-stroke population. Methods A one-month, 4x/week in-home regimen of either a high frequency (40Hz) or low frequency (20Hz) NMES program was applied to the hemiplegic thenar muscles of 16 persons with chronic stroke. Participants were identified a priori as having a low level of function (LF) or a high level of function (HF). Outcome measures of strength, dexterity, and endurance were measured before and after participation in the regimen. Results LF subjects showed no significant changes with either the high or the low frequency NMES regimen. HF subjects showed significant changes in strength, dexterity and endurance. Within this group, higher frequencies of stimulation yielded strength gains and increased motor activation; lower frequencies impacted dexterity and endurance. Conclusions The results suggest that higher frequencies of stimulation could be more effective in improving strength and motor activation properties and that lower frequencies may impact coordination and endurance changes; results also indicate that persons with a higher functional level of recovery may respond more favorably to NMES regimens, but further study with larger patient groups is warranted. PMID:23893829
Object Categorization in Finer Levels Relies More on Higher Spatial Frequencies and Takes Longer.
Ashtiani, Matin N; Kheradpisheh, Saeed R; Masquelier, Timothée; Ganjtabesh, Mohammad
2017-01-01
The human visual system contains a hierarchical sequence of modules that take part in visual perception at different levels of abstraction, i.e., superordinate, basic, and subordinate levels. One important question is to identify the "entry" level at which the visual representation is commenced in the process of object recognition. For a long time, it was believed that the basic level had a temporal advantage over two others. This claim has been challenged recently. Here we used a series of psychophysics experiments, based on a rapid presentation paradigm, as well as two computational models, with bandpass filtered images of five object classes to study the processing order of the categorization levels. In these experiments, we investigated the type of visual information required for categorizing objects in each level by varying the spatial frequency bands of the input image. The results of our psychophysics experiments and computational models are consistent. They indicate that the different spatial frequency information had different effects on object categorization in each level. In the absence of high frequency information, subordinate and basic level categorization are performed less accurately, while the superordinate level is performed well. This means that low frequency information is sufficient for superordinate level, but not for the basic and subordinate levels. These finer levels rely more on high frequency information, which appears to take longer to be processed, leading to longer reaction times. Finally, to avoid the ceiling effect, we evaluated the robustness of the results by adding different amounts of noise to the input images and repeating the experiments. As expected, the categorization accuracy decreased and the reaction time increased significantly, but the trends were the same. This shows that our results are not due to a ceiling effect. The compatibility between our psychophysical and computational results suggests that the temporal advantage of the superordinate (resp. basic) level to basic (resp. subordinate) level is mainly due to the computational constraints (the visual system processes higher spatial frequencies more slowly, and categorization in finer levels depends more on these higher spatial frequencies).
Object Categorization in Finer Levels Relies More on Higher Spatial Frequencies and Takes Longer
Ashtiani, Matin N.; Kheradpisheh, Saeed R.; Masquelier, Timothée; Ganjtabesh, Mohammad
2017-01-01
The human visual system contains a hierarchical sequence of modules that take part in visual perception at different levels of abstraction, i.e., superordinate, basic, and subordinate levels. One important question is to identify the “entry” level at which the visual representation is commenced in the process of object recognition. For a long time, it was believed that the basic level had a temporal advantage over two others. This claim has been challenged recently. Here we used a series of psychophysics experiments, based on a rapid presentation paradigm, as well as two computational models, with bandpass filtered images of five object classes to study the processing order of the categorization levels. In these experiments, we investigated the type of visual information required for categorizing objects in each level by varying the spatial frequency bands of the input image. The results of our psychophysics experiments and computational models are consistent. They indicate that the different spatial frequency information had different effects on object categorization in each level. In the absence of high frequency information, subordinate and basic level categorization are performed less accurately, while the superordinate level is performed well. This means that low frequency information is sufficient for superordinate level, but not for the basic and subordinate levels. These finer levels rely more on high frequency information, which appears to take longer to be processed, leading to longer reaction times. Finally, to avoid the ceiling effect, we evaluated the robustness of the results by adding different amounts of noise to the input images and repeating the experiments. As expected, the categorization accuracy decreased and the reaction time increased significantly, but the trends were the same. This shows that our results are not due to a ceiling effect. The compatibility between our psychophysical and computational results suggests that the temporal advantage of the superordinate (resp. basic) level to basic (resp. subordinate) level is mainly due to the computational constraints (the visual system processes higher spatial frequencies more slowly, and categorization in finer levels depends more on these higher spatial frequencies). PMID:28790954
Martínez-Palomino, Guadalupe; Vallejo, Maite; Gárcia-Moreno, Juan; López-Pérez, Maritza; Díaz-Granados, Rosario; Badillo-Castillo, Matilde Osvelia; Garza-Rodarte, Adriana
2008-01-01
Ischemic heart disease is the first cause of death in the world in both genders between 30 and 40 years of age. It has been proposed that socioeconomic status could affect the prevalence of cardiovascular risk factors (CVRF), as well as cardiovascular disease incidence and mortality. The purpose of this work was to compare the frequency of CVRF in two groups of women with different educational level. A higher frequency of visceral obesity was identified in the women with lower educational level and hypo-HDL-C in the group of women with higher educational level. Correlation between age and modifiable CVRF was different between the studied groups. A larger proportion of women with higher educational level than those with lower educational level drank alcoholic beverages and smoked cigarettes. Frequency of identified modifiable CVRF was similar to that found in other Hispanic-American populations. The inverse relationship between CVRF and educational level, a commonly used measure of socioeconomic status, and prevalence of CVRF informed in English and American studies was not observed in this investigation; probably because social and cultural conditions could affect the educational level in a different manner. Health education programs must take into account the cultural processes of each country, city, or community, regardless of the socioeconomic status, based on social and cultural backgrounds of each group.
Xu, Jin; Liao, Yun-Fei; Zhou, Wei-Ping; Ming, Hua-Li; Wang, Qing-Hai
2015-08-01
We aimed to evaluate the correlation of the monocyte chemoattractant protein 1 (MCP-1) A-2518G polymorphism with type 2 diabetes mellitus (T2DM) and vascular complications in T2DM, to aid in understanding its role in pathogenesis. A total of 150 T2DM patients and 50 healthy controls (group A) were enrolled. The T2DM patients were divided into three groups based on the absence of complications (group B) presence of microvascular disease (group C) or macrovascular disease (group D). DNA of all enrolled subjects was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for the MCP-1 A-2518G polymorphism. Serum MCP-1 levels were measured by an enzyme-linked immunosorbent assay (ELISA). Participants in group D had increased serum MCP-1 levels relative to group B, group C, and group A (all p<0.01). Compared with group A, the frequencies of the MCP-1 A-2518G G/G genotype and G allele were significantly higher in group C and group D (all p<0.05). In contrast to group B, group C had higher frequencies of the G/G genotype and G allele, while group D had higher G allele frequencies (all p<0.05). Logistic regression analysis showed that lower body-mass index (BMI) and free cholesterol (FC), as well as higher high-density lipoprotein cholesterol (HDL-C) levels may be the protective factors for T2DM, while higher levels of triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and G/G genotype frequency were independent risk factors for T2DM. Our data indicates a correlation between the MCP-1 A-2518G polymorphism with macrovascular complications in T2DM patients; lower BMI and FC, as well as higher HDL-C levels may be the protective factors for T2DM, while higher levels of TG, LDL-C, and G/G genotype frequency were independent risk factors for T2DM.
Zhang, Yumei; Jiang, Yanyan; Wang, Yanjuan; Liu, Hua; Shen, Yujuan; Yuan, Zhongying; Hu, Yuan; Xu, Yuxin; Cao, Jianping
2015-01-01
The current knowledge of immunological responses to schistosomiasis is insufficient for the development of vaccine and therapies. The role of T follicular helper (Tfh) cells in schistosome infections is not fully defined. The frequency of circulating Tfh cells and serum cytokine levels were analyzed in 11 patients with chronic schistosomiasis and 10 healthy controls (HC), who reside in an endemic area for Schistosomiasis japonicum. Significantly higher frequencies of circulating CXCR5+ CD4+ Tfh cells and higher expression levels of ICOS and PD-1 in CXCR5+ CD4+ Tfh cells were observed in patients with chronic schistosomiasis compared to HC. The levels of IL-21 in serum and the expression of IL-21 mRNA were higher in chronic schistosomiasis patients than in HC. Moreover, the frequency of circulating PD-1high CXCR5+ CD4+ Tfh cells positively correlated with the levels of IL-21 in serum from patients with chronic schistosomiasis. A positive correlation was also found between the frequency of PD-1high CXCR5+ CD4+ Tfh cells and the levels of soluble egg antigen (SEA)-specific antibodies in serum samples from the patient group. Our study is the first regarding Tfh cells in chronic human schistosomiasis and the finding indicate that PD-1high CXCR5+ CD4+Tfh cells might play an important role in the production of specific antibodies in schistosomiasis. This study contributes to the understanding of immune response to schistosomiasis and may provide helpful support in vaccine development. PMID:26221072
Zhang, Yumei; Jiang, Yanyan; Wang, Yanjuan; Liu, Hua; Shen, Yujuan; Yuan, Zhongying; Hu, Yuan; Xu, Yuxin; Cao, Jianping
2015-01-01
The current knowledge of immunological responses to schistosomiasis is insufficient for the development of vaccine and therapies. The role of T follicular helper (Tfh) cells in schistosome infections is not fully defined. The frequency of circulating Tfh cells and serum cytokine levels were analyzed in 11 patients with chronic schistosomiasis and 10 healthy controls (HC), who reside in an endemic area for Schistosomiasis japonicum. Significantly higher frequencies of circulating CXCR5(+) CD4(+) Tfh cells and higher expression levels of ICOS and PD-1 in CXCR5(+) CD4(+) Tfh cells were observed in patients with chronic schistosomiasis compared to HC. The levels of IL-21 in serum and the expression of IL-21 mRNA were higher in chronic schistosomiasis patients than in HC. Moreover, the frequency of circulating PD-1(high) CXCR5(+) CD4(+) Tfh cells positively correlated with the levels of IL-21 in serum from patients with chronic schistosomiasis. A positive correlation was also found between the frequency of PD-1(high) CXCR5(+) CD4(+) Tfh cells and the levels of soluble egg antigen (SEA)-specific antibodies in serum samples from the patient group. Our study is the first regarding Tfh cells in chronic human schistosomiasis and the finding indicate that PD-1(high) CXCR5(+) CD4(+)Tfh cells might play an important role in the production of specific antibodies in schistosomiasis. This study contributes to the understanding of immune response to schistosomiasis and may provide helpful support in vaccine development.
Adachi, Paul J C; Willoughby, Teena
2014-01-01
The frequency of involvement in sports often has been concurrently and longitudinally associated with higher self-esteem. The interpretation of this association consistently has been framed as involvement in sports leading to higher levels of self-esteem over time (i.e., socialization effect), although no studies have tested whether higher levels of self-esteem lead to increased involvement in sports over time (i.e., selection effect). Another important aspect of involvement in sports that may be related to self-esteem is the degree to which youth enjoy sports. However, this aspect has received much less attention. To address these gaps in the literature, we first examined the bidirectional effects between self-esteem and the frequency of involvement in sports with 1,492 adolescents (50.8 % female; 92.4 % Canadian-born) over 4 years. Higher levels of self-esteem predicted greater involvement in sports over time, but greater involvement in sports did not predict higher levels of self-esteem over time, offering support only for selection effects. We then tested the bidirectional effects between the enjoyment of sports and self-esteem and found evidence of both socialization and selection effects. Specifically, greater enjoyment of sports predicted higher self-esteem over time, and higher self-esteem predicted greater enjoyment of sports over time. These novel findings suggest that adolescents with higher self-esteem play sports more frequently and enjoy sports more than adolescents with lower self-esteem. In addition, the degree to which adolescents enjoy sports may be more important for increasing self-esteem than the frequency with which adolescents play sports.
Gospić, Nikolina Rako; Picciulin, Marta
2016-04-15
The habitat of the resident bottlenose dolphins (Tursiops truncatus) of the Cres-Lošinj archipelago overlaps with routes of intense boat traffic. Within these waters, Sea Ambient Noise (SAN) was sampled across ten acoustic stations between 2007 and 2009. Data on boat presence was concurrently collected and when dolphins were sighted group behaviour was also recorded. Acoustic recordings were analysed for 1/3 octave bands. Samples containing dolphin whistles were analysed and compared with boat presence and SAN levels. Results indicate that dolphins whistle at higher frequencies in conditions of elevated low frequency noise. Conversely, they reduce maximum, delta and start frequencies and frequency modulations when noise levels increase significantly across higher frequencies. The study shows that high levels of SAN causes significant changes in the acoustic structure of dolphin whistles. Additionally, changes in whistle parameters, in the presence of boats, appear to be related to the behavioural state of the dolphin group. Copyright © 2016 Elsevier Ltd. All rights reserved.
Marmel, Frederic; Marrufo-Pérez, Miriam I; Heeren, Jan; Ewert, Stephan; Lopez-Poveda, Enrique A
2018-06-14
The detection of high-frequency spectral notches has been shown to be worse at 70-80 dB sound pressure level (SPL) than at higher levels up to 100 dB SPL. The performance improvement at levels higher than 70-80 dB SPL has been related to an 'ideal observer' comparison of population auditory nerve spike trains to stimuli with and without high-frequency spectral notches. Insofar as vertical localization partly relies on information provided by pinna-based high-frequency spectral notches, we hypothesized that localization would be worse at 70-80 dB SPL than at higher levels. Results from a first experiment using a virtual localization set-up and non-individualized head-related transfer functions (HRTFs) were consistent with this hypothesis, but a second experiment using a free-field set-up showed that vertical localization deteriorates monotonically with increasing level up to 100 dB SPL. These results suggest that listeners use different cues when localizing sound sources in virtual and free-field conditions. In addition, they confirm that the worsening in vertical localization with increasing level continues beyond 70-80 dB SPL, the highest levels tested by previous studies. Further, they suggest that vertical localization, unlike high-frequency spectral notch detection, does not rely on an 'ideal observer' analysis of auditory nerve spike trains. Copyright © 2018 Elsevier B.V. All rights reserved.
Tervo, Outi M; Christoffersen, Mads F; Simon, Malene; Miller, Lee A; Jensen, Frants H; Parks, Susan E; Madsen, Peter T
2012-01-01
The low-frequency, powerful vocalizations of blue and fin whales may potentially be detected by conspecifics across entire ocean basins. In contrast, humpback and bowhead whales produce equally powerful, but more complex broadband vocalizations composed of higher frequencies that suffer from higher attenuation. Here we evaluate the active space of high frequency song notes of bowhead whales (Balaena mysticetus) in Western Greenland using measurements of song source levels and ambient noise. Four independent, GPS-synchronized hydrophones were deployed through holes in the ice to localize vocalizing bowhead whales, estimate source levels and measure ambient noise. The song had a mean apparent source level of 185±2 dB rms re 1 µPa @ 1 m and a high mean centroid frequency of 444±48 Hz. Using measured ambient noise levels in the area and Arctic sound spreading models, the estimated active space of these song notes is between 40 and 130 km, an order of magnitude smaller than the estimated active space of low frequency blue and fin whale songs produced at similar source levels and for similar noise conditions. We propose that bowhead whales spatially compensate for their smaller communication range through mating aggregations that co-evolved with broadband song to form a complex and dynamic acoustically mediated sexual display.
Tervo, Outi M.; Christoffersen, Mads F.; Simon, Malene; Miller, Lee A.; Jensen, Frants H.; Parks, Susan E.; Madsen, Peter T.
2012-01-01
The low-frequency, powerful vocalizations of blue and fin whales may potentially be detected by conspecifics across entire ocean basins. In contrast, humpback and bowhead whales produce equally powerful, but more complex broadband vocalizations composed of higher frequencies that suffer from higher attenuation. Here we evaluate the active space of high frequency song notes of bowhead whales (Balaena mysticetus) in Western Greenland using measurements of song source levels and ambient noise. Four independent, GPS-synchronized hydrophones were deployed through holes in the ice to localize vocalizing bowhead whales, estimate source levels and measure ambient noise. The song had a mean apparent source level of 185±2 dB rms re 1 µPa @ 1 m and a high mean centroid frequency of 444±48 Hz. Using measured ambient noise levels in the area and Arctic sound spreading models, the estimated active space of these song notes is between 40 and 130 km, an order of magnitude smaller than the estimated active space of low frequency blue and fin whale songs produced at similar source levels and for similar noise conditions. We propose that bowhead whales spatially compensate for their smaller communication range through mating aggregations that co-evolved with broadband song to form a complex and dynamic acoustically mediated sexual display. PMID:23300591
Sayal, Kapil; Townsend, Ellen
2016-01-01
This study investigated the relationship between experiential avoidance, coping and the recency and frequency of self-harm, in a community sample (N = 1332, aged 16–69 years). Participants completed online, self-report measures assessing self-harm, momentary affect, experiential avoidance and coping in response to a recent stressor. Participants who had self-harmed reported significantly higher levels of experiential avoidance and avoidance coping, as well as lower levels of approach, reappraisal and emotional regulation coping, than those with no self-harm history. Moreover, more recent self-harm was associated with lower endorsement of approach, reappraisal and emotion regulation coping, and also higher levels of both avoidance coping and experiential avoidance. Higher experiential avoidance and avoidance coping also predicted increased lifetime frequency of self-harm. Conversely, increased approach and reappraisal coping were associated with a decreased likelihood of high frequency self-harm. Although some of the effects were small, particularly in relation to lifetime frequency of self-harm, overall our results suggest that experiential avoidance tendency may be an important psychological factor underpinning self-harm, regardless of suicidal intent (e.g. including mixed intent, suicidal intent, ambivalence), which is not accounted for in existing models of self-harm. PMID:27442036
Noise attenuation characteristics of a foam type earplug measured using a dummy head.
Idota, Nozomi; Horie, Seichi; Tsutsui, Takao; Inoue, Jinro
2002-03-01
The attenuation characteristics of the earplug using a dummy head (KEMAR; Knowles Electronics Manikin for Acoustic Research) were measured, when it was exposed to pure tones or broadband noises at three different sound pressure levels (SPLs) of 70, 80 and 90 dB SPL in the 'wide frequency range from 250 to 20 k Hz. We ascertained the satisfactory capacity of noise attenuation except for from 10 k to 14 k Hz. The noise attenuation level increased with frequency until 2 k Hz, became almost constant until 8 k Hz, then decreased at around 10 k to 14 k Hz, and recovered in the range from 16 k to 20 k Hz. The frequency characteristics were identical among three different sound pressure levels and almost identical between pure tones and broadband noises. The change of frequency characteristics affected by the depth of the earplug that was inserted into the artificial ear canal of the KEMAR was also investigated. Measured sound pressure level by the builetin microphone in the KEMAR revealed a region in which the measured sound pressure levels were relatively higher around 10 k Hz. The frequency of the region moved higher when the earplug was inserted more deeply. Therefore it was considered that this phenomenon was related to the resonance frequency of the cylinder-like cavity made between the end section of the earplug and the diaphragm of the built-in microphone.
Hellström, Charlotta; Wagner, Philippe; Nilsson, Kent W; Leppert, Jerzy; Åslund, Cecilia
2017-06-01
To investigate the associations between gambling frequency, attention-deficit hyperactivity disorder (ADHD) symptoms, and problem gambling among adolescent boys and girls. One hypothesis was that adolescents with increased ADHD symptoms have a higher frequency of gambling compared to adolescents with fewer ADHD symptoms. A population-based sample of adolescents (aged 15-18 years) completed a questionnaire on demographics, gambling habits, ADHD symptoms, and problematic gambling; 1412 adolescents (from 4440 sampled) with gambling experience were included in the final sample. A zero-inflated negative binomial regression analysis revealed that increased ADHD symptoms, higher gambling frequency, and higher age were associated with lower odds for being non-susceptible to gambling problems. Moreover, gambling frequency interacted with ADHD symptoms in predicting probability of being non-susceptible to gambling problems. However, when analysing those already susceptible to problem gambling, ADHD symptoms did not modify the effect of gambling frequency on the expected magnitude of gambling problems. In susceptible individuals, problem gambling increased with both increased ADHD symptoms and increased gambling frequency, but the level of problems due to gambling frequency did not change depending on the ADHD symptom level. There was an interaction effect between sex and gambling frequency in relation to gambling problems. Adolescents with ADHD symptoms seem to be more sensitive to gambling, in terms of being susceptible to developing gambling problems. However, once susceptible, adolescents with ADHD symptoms are affected by gambling frequency similarly to other susceptible participants.
NASA Astrophysics Data System (ADS)
Sharma, S.; Sirse, N.; Turner, M. M.; Ellingboe, A. R.
2018-06-01
One-dimensional particle-in-cell simulation is used to simulate the capacitively coupled argon plasma for a range of excitation frequency from 13.56 MHz to 100 MHz. The argon chemistry set can, selectively, include two metastable levels enabling multi-step ionization and metastable pooling. The results show that the plasma density decreases when metastable atoms are included with higher discrepancy at a higher excitation frequency. The contribution of multistep ionization to the overall density increases with the excitation frequency. The electron temperature increases with the inclusion of metastable atoms and decreases with the excitation frequency. At a lower excitation frequency, the density of Ar** (3p5 4p, 13.1 eV) is higher than that of Ar* (3p5 4s, 11.6 eV), whereas at higher excitation frequencies, the Ar* (3p5 4s, 11.6 eV) is the dominant metastable atom. The metastable and electron temperature profile evolve from a parabolic profile at a lower excitation frequency to a saddle type profile at a higher excitation frequency. With metastable, the electron energy distribution function (EEDF) changes its shape from Druyvesteyn type, at a low excitation frequency, to bi-Maxwellian, at a high frequency plasma excitation; however, a three-temperature EEDF is observed without metastable atoms.
Study of double wall panels for use in propeller driven aircraft
NASA Technical Reports Server (NTRS)
Atwal, M.; Bernhard, R.
1984-01-01
Propeller driven aircraft have exhibited high levels of interior noise. Most absorption materials are not effective at low frequencies where maximum noise levels occur. Two panels separated by an air gap are suggested as an alternative means of noise attenuation. This design produces an impedance mismatch where a sound wave travels backwards to the source. The higher the impedance, the higher the reflected soundwave intensity. Two aluminum panels with helium in between and two panels with one being perforated were investigated. Helium increases the transmission loss because of a greater impedance mismatch than air. The transmission loss of the unperforated panel is higher throughout the frequency range tested.
Study of double wall panels for use in propeller driven aircraft
NASA Astrophysics Data System (ADS)
Atwal, M.; Bernhard, R.
1984-05-01
Propeller driven aircraft have exhibited high levels of interior noise. Most absorption materials are not effective at low frequencies where maximum noise levels occur. Two panels separated by an air gap are suggested as an alternative means of noise attenuation. This design produces an impedance mismatch where a sound wave travels backwards to the source. The higher the impedance, the higher the reflected soundwave intensity. Two aluminum panels with helium in between and two panels with one being perforated were investigated. Helium increases the transmission loss because of a greater impedance mismatch than air. The transmission loss of the unperforated panel is higher throughout the frequency range tested.
NASA Technical Reports Server (NTRS)
Powell, C. A.; Mccurdy, D. A.
1978-01-01
Fifty-two airplane noise recordings, made at several locations around Dulles International Airport, were analyzed to compare the low-frequency noise levels of the Concorde supersonic transport with those of other commercial jet airplanes. Comparisons of the relative low-frequency noise levels which were produced at close and distant locations for departures and arrivals were made for three noise measures: the sound pressure level in the 1/3 octave band centered at 20 Hz, the total sound pressure level in the 1/3 octave bands with center frequencies less than or equal to 125 Hz, and the total sound pressure level in the 1/3 octave bands with center frequencies less than or equal to 500 Hz. Although the absolute noise levels for Concorde were found, in general, to be higher than those for the other airplane types, the level of low-frequency noise of the Concorde relative to the perceived noise level (PNL), effective perceived noise level (EPNL), and overall sound pressure level (OASPL) was within the range established by the other airplane types, except for the arrival operations of four-engine, narrow-body airplanes. The measure OASPL was found to be a significantly better predictor of low-frequency noise level than PNL or EPNL.
Low-frequency noise from large wind turbines.
Møller, Henrik; Pedersen, Christian Sejer
2011-06-01
As wind turbines get larger, worries have emerged that the turbine noise would move down in frequency and that the low-frequency noise would cause annoyance for the neighbors. The noise emission from 48 wind turbines with nominal electric power up to 3.6 MW is analyzed and discussed. The relative amount of low-frequency noise is higher for large turbines (2.3-3.6 MW) than for small turbines (≤ 2 MW), and the difference is statistically significant. The difference can also be expressed as a downward shift of the spectrum of approximately one-third of an octave. A further shift of similar size is suggested for future turbines in the 10-MW range. Due to the air absorption, the higher low-frequency content becomes even more pronounced, when sound pressure levels in relevant neighbor distances are considered. Even when A-weighted levels are considered, a substantial part of the noise is at low frequencies, and for several of the investigated large turbines, the one-third-octave band with the highest level is at or below 250 Hz. It is thus beyond any doubt that the low-frequency part of the spectrum plays an important role in the noise at the neighbors. © 2011 Acoustical Society of America
2012-01-01
Background Alcohol drinking is a risk factor for harm and disease. A low level of drinking among non-Western immigrants may lead to less alcohol-related harm and disease. The first aim of this study was to describe frequency of drinking in two generations of immigrants in Oslo, contrasting the result to drinking frequency among ethnic Norwegians. The second aim was to study how frequency of drinking among adult immigrants was associated with social interaction with their own countrymen and ethnic Norwegians, acculturation, age, gender, socioeconomic factors and the Muslim faith. Method The Oslo Health Study (HUBRO) was conducted during the period 2000 to 2002 and consisted of three separate surveys: a youth study (15-16-year-olds, a total of 7343 respondents, response rate 88.3%); adult cohorts from 30 to 75 years old (18,770 respondents, response rate 46%); the five largest immigrant groups in Oslo (aged 20–60 years, a total of 3019 respondents, response rate 39.7%). Based on these three surveys, studies of frequency of drinking in the previous year (four categories) were conducted among 15-16-year-olds and their parents’ generation, 30-60-year-old Iranians, Pakistanis, Turks and ethnic Norwegians. A structural equation model with drinking frequency as outcome was established for the adult immigrants. Results Adults and youth of ethnic Norwegian background reported more frequent alcohol use than immigrants with backgrounds from Iran, Turkey and Pakistan. Iranians reported a higher drinking frequency than Turks and Pakistanis. In the structural equation model high drinking frequency was associated with high host culture competence and social interaction, while high own culture competence was associated with low drinking frequency. Adult first-generation immigrants with a longer stay in Norway, those of a higher age, and females drank alcohol less frequently, while those with a higher level of education and work participation drank more frequently. Muslim immigrants reported a significantly lower drinking frequency than non-Muslims, although this did not apply to Iranians. Conclusions The existence and growth in Western societies of immigrant groups with low-level alcohol consumption contributed to a lower level of consumption at the population level. This may imply reduced drinking and alcohol-related harm and disease even among ethnic Norwegians. PMID:22824456
Amundsen, Ellen J
2012-07-23
Alcohol drinking is a risk factor for harm and disease. A low level of drinking among non-Western immigrants may lead to less alcohol-related harm and disease. The first aim of this study was to describe frequency of drinking in two generations of immigrants in Oslo, contrasting the result to drinking frequency among ethnic Norwegians. The second aim was to study how frequency of drinking among adult immigrants was associated with social interaction with their own countrymen and ethnic Norwegians, acculturation, age, gender, socioeconomic factors and the Muslim faith. The Oslo Health Study (HUBRO) was conducted during the period 2000 to 2002 and consisted of three separate surveys: a youth study (15-16-year-olds, a total of 7343 respondents, response rate 88.3%); adult cohorts from 30 to 75 years old (18,770 respondents, response rate 46%); the five largest immigrant groups in Oslo (aged 20-60 years, a total of 3019 respondents, response rate 39.7%). Based on these three surveys, studies of frequency of drinking in the previous year (four categories) were conducted among 15-16-year-olds and their parents' generation, 30-60-year-old Iranians, Pakistanis, Turks and ethnic Norwegians. A structural equation model with drinking frequency as outcome was established for the adult immigrants. Adults and youth of ethnic Norwegian background reported more frequent alcohol use than immigrants with backgrounds from Iran, Turkey and Pakistan. Iranians reported a higher drinking frequency than Turks and Pakistanis. In the structural equation model high drinking frequency was associated with high host culture competence and social interaction, while high own culture competence was associated with low drinking frequency. Adult first-generation immigrants with a longer stay in Norway, those of a higher age, and females drank alcohol less frequently, while those with a higher level of education and work participation drank more frequently. Muslim immigrants reported a significantly lower drinking frequency than non-Muslims, although this did not apply to Iranians. The existence and growth in Western societies of immigrant groups with low-level alcohol consumption contributed to a lower level of consumption at the population level. This may imply reduced drinking and alcohol-related harm and disease even among ethnic Norwegians.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-01
... field versus laboratory conditions. While multiple controlled studies of high-frequency cetaceans to... of behavioral response translates to other high-frequency cetaceans (Southall et al., 2007). There... exposures at higher levels. Jacobs and Terhune (2002) observed wild harbor seal reactions to high-frequency...
Fernández-de-Las-Peñas, César; Benito-González, Elena; Palacios-Ceña, María; Wang, Kelun; Castaldo, Matteo; Arendt-Nielsen, Lars
2017-12-01
Identification of subgroups of patients with different levels of sensitization and clinical features can help to identify groups at risk and the development of better therapeutic strategies. The aim of this study was to identify subgroups of patients with tension type headache (TTH) with different levels of sensitization, clinical pain features, and psychological outcomes. A total of 197 individuals with TTH participated. Headache intensity, frequency, and duration and medication intake were collected with a 4-weeks diary. Pressure pain thresholds were assessed bilaterally over the temporalis muscle, C5-C6 joint, second metacarpal and tibialis anterior muscle to determine widespread pressure pain hyperalgesia. The Hospital Anxiety and Depression Scale assessed anxiety and depression. The State-Trait Anxiety Inventory evaluated the state and trait levels of anxiety. The Headache Disability Inventory evaluated the burden of headache. Health-related quality of life was determined with the SF-36 questionnaire. Groups were considered as positive (three or more criteria) or negative (less than three criteria) on a clinical prediction rule: headache duration <8.5 h/day; headache frequency <5.5 days/week; bodily pain <47 and vitality <47.5. The ANCOVA revealed that subjects in group 1 (positive rule, n = 89) exhibited longer headache history, shorter headache duration, lower headache frequency, higher widespread pressure hyperalgesia, higher anxiety trait levels, and lower quality of life (all, P < 0.01) than those subjects within group 2 (negative rule, n = 108). Differences were similar between men and women. This study identified a subgroup of patients with TTH with higher sensitization, higher chronicity of headaches and worse quality of life but lower frequency and duration of headache episodes. This subgroup of individuals with TTH may need particular attention and specific therapeutic programs for avoiding potential chronification.
Level of Automation and Failure Frequency Effects on Simulated Lunar Lander Performance
NASA Technical Reports Server (NTRS)
Marquez, Jessica J.; Ramirez, Margarita
2014-01-01
A human-in-the-loop experiment was conducted at the NASA Ames Research Center Vertical Motion Simulator, where instrument-rated pilots completed a simulated terminal descent phase of a lunar landing. Ten pilots participated in a 2 x 2 mixed design experiment, with level of automation as the within-subjects factor and failure frequency as the between subjects factor. The two evaluated levels of automation were high (fully automated landing) and low (manual controlled landing). During test trials, participants were exposed to either a high number of failures (75% failure frequency) or low number of failures (25% failure frequency). In order to investigate the pilots' sensitivity to changes in levels of automation and failure frequency, the dependent measure selected for this experiment was accuracy of failure diagnosis, from which D Prime and Decision Criterion were derived. For each of the dependent measures, no significant difference was found for level of automation and no significant interaction was detected between level of automation and failure frequency. A significant effect was identified for failure frequency suggesting failure frequency has a significant effect on pilots' sensitivity to failure detection and diagnosis. Participants were more likely to correctly identify and diagnose failures if they experienced the higher levels of failures, regardless of level of automation
NASA Technical Reports Server (NTRS)
Whorton, M. S.; Eldridge, J. T.; Ferebee, R. C.; Lassiter, J. O.; Redmon, J. W., Jr.
1998-01-01
As a research facility for microgravity science, the International Space Station (ISS) will be used for numerous investigations such as protein crystal growth, combustion, and fluid mechanics experiments which require a quiescent acceleration environment across a broad spectrum of frequencies. These experiments are most sensitive to low-frequency accelerations and can tolerate much higher accelerations at higher frequency. However, the anticipated acceleration environment on ISS significantly exceeds the required acceleration level. The ubiquity and difficulty in characterization of the disturbance sources precludes source isolation, requiring vibration isolation to attenuate the anticipated disturbances to an acceptable level. This memorandum reports the results of research in active control methods for microgravity vibration isolation.
Do infants with cow's milk protein allergy have inadequate levels of vitamin D?
Silva, Cristiane M; Silva, Silvia A da; Antunes, Margarida M de C; Silva, Gisélia Alves Pontes da; Sarinho, Emanuel Sávio Cavalcanti; Brandt, Katia G
To verify whether infants with cow's milk protein allergy have inadequate vitamin D levels. This cross-sectional study included 120 children aged 2 years or younger, one group with cow's milk protein allergy and a control group. The children were recruited at the pediatric gastroenterology, allergology, and pediatric outpatient clinics of a university hospital in the Northeast of Brazil. A questionnaire was administered to the caregiver and blood samples were collected for vitamin D quantification. Vitamin D levels <30ng/mL were considered inadequate. Vitamin D level was expressed as mean and standard deviation, and the frequency of the degrees of sufficiency and other variables, as proportions. Infants with cow's milk protein allergy had lower mean vitamin D levels (30.93 vs.35.29ng/mL; p=0.041) and higher deficiency frequency (20.3% vs.8.2; p=0.049) than the healthy controls. Exclusively or predominantly breastfed infants with cow's milk protein allergy had higher frequency of inadequate vitamin D levels (p=0.002). Regardless of sun exposure time, the groups had similar frequencies of inadequate vitamin D levels (p=0.972). Lower vitamin D levels were found in infants with CMPA, especially those who were exclusively or predominantly breastfed, making these infants a possible risk group for vitamin D deficiency. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.
Etlinger, S C; Guttmann, G; Bauer, H
1986-07-01
A description of scalp-recorded, spontaneous, cerebral DC-potential shifts is given independent of other variables (shift stereotypy), in relationship to higher frequencies (theta, alpha 1, alpha 2: 4-13 Hz) and as analyzed pairwise across the median sagittal line (Fz, Cz, Pz) separately according to frequency and condition (relaxation and moderate mental load). Spontaneous DC-shifts are shown to behave unpredictably. Whether measured jointly (up to triads) or as dyad and triad context entropy, the frontal DC-shifts are calculated as being random, whereby their definition as such within the context of the Principle Component Analysis is supported by the analysis of longitudinal registrations. Cross-correlation analysis of the cerebral slow potential's relationship to each of the higher frequencies (theta, alpha 1, alpha 2) reveals it to be highly independent, the highest correlation accounting for merely 11% of the common variance, the average being 9% (R congruent to 0.3). By matching the conjoint activity of the DC-potential between Fz-Cz, Cz-Pz, and Fz-Pz to that of theta, alpha 1, alpha 2 at the same paired sites, the DC-activity is shown to be operating at higher levels of synchronous activity than the higher frequencies, regardless of pairing and/or condition, although the general level of synchronous activity (DC, theta, alpha 1, alpha 2) is remarkably high along the median sagittal line, 75% of the correlation averages of all analysis-pairings being above 0.60.
Thunderstorms and ground-based radio noise as observed by radio astronomy Explorer 1
NASA Technical Reports Server (NTRS)
Caruso, J. A.; Herman, J. R.
1973-01-01
Radio Astronomy Explorer (RAE) data were analyzed to determine the frequency dependence of HF terrestrial radio noise power. RAE observations of individual thunderstorms, mid-ocean areas, and specific geographic regions for which concommitant ground based measurements are available indicate that noise power is a monotonically decreasing function of frequency which conforms to expectations over the geographic locations and time periods investigated. In all cases investigated, active thunderstorm regions emit slightly higher power as contrasted to RAE observations of the region during meteorologically quiet periods. Noise levels are some 15 db higher than predicted values over mid-ocean, while in locations where ground based measurements are available a maximum deviation of 5 db occurs. Worldwide contour mapping of the noise power at 6000 km for five individual months and four observing frequencies, examples of which are given, indicate high noise levels over continental land masses with corresponding lower levels over ocean regions.
Cocaine effects on pulsatile secretion of anterior pituitary, gonadal, and adrenal hormones.
Mendelson, J H; Mello, N K; Teoh, S K; Ellingboe, J; Cochin, J
1989-12-01
Pulse frequency analysis of LH, PRL, testosterone, and cortisol was carried out with the Cluster Analysis Program in eight male cocaine abusers and eight aged-matched normal men. Four of the eight cocaine abusers had hyperprolactinemia (range, 22.08-44.65 micrograms/L). Cocaine users as a group had significantly higher mean peak height (P less than 0.02) than control subjects. Cocaine users with hyperprolactinemia had higher mean peak height than control subjects or cocaine users with normal PRL levels (P less than 0.01). Cocaine users with hyperprolactinemia also had higher mean amplitude increments than control subjects (P less than 0.02). Cocaine users with hyperprolactinemia had a higher mean valley than controls (P less than 0.01) and cocaine users with normal PRL levels (P less than 0.03). However, there were no significant differences in PRL peak frequency, peak duration, or interpulse intervals between cocaine users with or without hyperprolactinemia and control subjects. There were minimal differences between cocaine users and control subjects in pulse frequency analysis of LH parameters; the small differences in mean LH levels and average interpulse interval were not in the abnormal range and were probably not biologically significant. No differences between cocaine users and controls were detected for pulse frequency analysis of testosterone or cortisol. Cocaine-induced hyperprolactinemia may contribute to disorders of sexual and reproductive function in men who abuse the drug, and recent reports that PRL modulates immune function suggest that cocaine-induced derangements of PRL secretion may also contribute to cocaine-related comorbidity in infectious disease. Since cocaine users with hyperprolactinemia had a higher mean valley as well as a higher peak pulse PRL height than control subjects, but did not have greater PRL pulse frequencies, we conclude that hyperprolactinemia in these men may be due to a cocaine-induced derangement of dopaminergic inhibition of basal PRL secretion.
Species-specific beaked whale echolocation signals.
Baumann-Pickering, Simone; McDonald, Mark A; Simonis, Anne E; Solsona Berga, Alba; Merkens, Karlina P B; Oleson, Erin M; Roch, Marie A; Wiggins, Sean M; Rankin, Shannon; Yack, Tina M; Hildebrand, John A
2013-09-01
Beaked whale echolocation signals are mostly frequency-modulated (FM) upsweep pulses and appear to be species specific. Evolutionary processes of niche separation may have driven differentiation of beaked whale signals used for spatial orientation and foraging. FM pulses of eight species of beaked whales were identified, as well as five distinct pulse types of unknown species, but presumed to be from beaked whales. Current evidence suggests these five distinct but unidentified FM pulse types are also species-specific and are each produced by a separate species. There may be a relationship between adult body length and center frequency with smaller whales producing higher frequency signals. This could be due to anatomical and physiological restraints or it could be an evolutionary adaption for detection of smaller prey for smaller whales with higher resolution using higher frequencies. The disadvantage of higher frequencies is a shorter detection range. Whales echolocating with the highest frequencies, or broadband, likely lower source level signals also use a higher repetition rate, which might compensate for the shorter detection range. Habitat modeling with acoustic detections should give further insights into how niches and prey may have shaped species-specific FM pulse types.
Alcohol and Psychoactive Substance Use among University Students in Edirne and Related Parameters
GÖRGÜLÜ, Yasemin; ÇAKIR, Diğdem; SÖNMEZ, Mehmet Bülent; KÖSE ÇINAR, Rugül; VARDAR, Mehmet Erdal
2016-01-01
Introduction Alcohol and psychoactive substance use and their effects are an important issue among adolescents and young adults. Different results have been reported about the frequency of alcohol and psychoactive substance use among university students in studies conducted both in Turkey and in different places worldwide. Methods The frequency of alcohol and psychoactive substance use among Trakya University students (n=1385) and the related parameters were studied cross-sectionally using a self-reporting questionnaire. Results Alcohol was the most common substance used (30%), followed by tobacco (29.9%) and marijuana (3.1%). The frequency of alcohol and psychoactive substance use was found to be higher among males with higher amounts of pocket money, whose parents experienced more conflict in their relationship, and who belong to families with a higher education and income level. Conclusion The frequency of alcohol and psychoactive substance use among Trakya University students was found to be lower than other regions in Turkey and particularly lower than the levels reported in studies conducted in other countries. PMID:28360790
Zhang, Xinghui; Li, Yajun; Zhang, Qin; Lu, Furong; Wang, Yun
2014-05-01
The purpose of this study was to examine the prevalence of smoking in a nationally representative sample of Chinese elementary and middle school students and to investigate its risk factors from families and schools. The data were from the National Children's Study of China (NCSC), in which 24,013 fourth- to ninth-grade students were recruited from 100 counties in 31 provinces in China. Chi-square tests and one-way ANOVAs were used to analyze the relationships between smoking and the risk factors. Logistic regressions were used to calculate odds ratios. The prevalence of ever smokers and current smokers were 19.0% and 5.4%. Focusing on current smokers, boys, middle school students, rural students, boarding students, non-only children and those owning parents with low educational levels reported smoking significantly more than girls, elementary school students, urban students, non-boarding students, only children and those owning parents with high educational levels. Lower trust and support from teachers and higher parent-child conflict positively predicted both smoking and smoking frequency. Lower trust and support from classmates was associated with higher possibility of smoking. However, higher trust and support from classmates was associated with higher smoking frequency. Teacher smoking and friend smoking were only predictive of smoking, but not of smoking frequency. Boys, middle school students, rural students, boarding students, non-only children and those owning parents with low educational levels need special attention. The most risk factors for smoking and smoking frequency were lower trust and support from teachers and higher parent-child conflict. Copyright © 2014 Elsevier Ltd. All rights reserved.
Johannes, Amélie; Zollhoefer, Bernd; Eujen, Ulrike; Kredel, Markus; Rauch, Stefan; Roewer, Norbert; Muellenbach, Ralf M
2013-04-01
Oxygenation during high-frequency oscillatory ventilation is secured by a high level of mean airway pressure. Our objective was to identify a pressure difference between the airway opening of the respiratory circuit and the trachea during application of different oscillatory frequencies. Six female Pietrain pigs (57.1 ± 3.6 kg) were first ventilated in a conventional mechanical ventilation mode. Subsequently, the animals were switched to high-frequency oscillatory ventilation by setting mean airway opening pressure 5 cmH(2)O above the one measured during controlled mechanical ventilation. Measurements at the airway opening and at tracheal levels were performed in healthy lungs and after induction of acute lung injury by surfactant depletion. During high-frequency oscillatory ventilation, the airway opening pressure was set at a constant level. The pressure amplitude was fixed at 90 cmH(2)O. Starting from an oscillatory frequency of 3 Hz, the frequency was increased in steps of 3 Hz to 15 Hz and then decreased accordingly. At each frequency, measurements were performed in the trachea through a side-lumen of the endotracheal tube and the airway opening pressure was recorded. The pressure difference was calculated. At every oscillatory frequency, a pressure loss towards the trachea could be shown. This pressure difference increased with higher oscillatory frequencies (3 Hz 2.2 ± 2.1 cmH(2)O vs. 15 Hz 7.5 ± 1.8 cmH(2)O). The results for healthy and injured lungs were similar. Tracheal pressures decreased with higher oscillatory frequencies. This may lead to pulmonary derecruitment. This has to be taken into consideration when increasing oscillatory frequencies and differentiated pressure settings are mandatory.
Cheng, Liang; Wang, Shao-Hui; Peng, Kang; Liao, Xiao-Mei
2017-01-01
Most citizen people are exposed daily to environmental noise at moderate levels with a short duration. The aim of the present study was to determine the effects of daily short-term exposure to moderate noise on sound level processing in the auditory midbrain. Sound processing properties of auditory midbrain neurons were recorded in anesthetized mice exposed to moderate noise (80 dB SPL, 2 h/d for 6 weeks) and were compared with those from age-matched controls. Neurons in exposed mice had a higher minimum threshold and maximum response intensity, a longer first spike latency, and a higher slope and narrower dynamic range for rate level function. However, these observed changes were greater in neurons with the best frequency within the noise exposure frequency range compared with those outside the frequency range. These sound processing properties also remained abnormal after a 12-week period of recovery in a quiet laboratory environment after completion of noise exposure. In conclusion, even daily short-term exposure to moderate noise can cause long-term impairment of sound level processing in a frequency-specific manner in auditory midbrain neurons.
Cheng, Liang; Wang, Shao-Hui; Peng, Kang
2017-01-01
Most citizen people are exposed daily to environmental noise at moderate levels with a short duration. The aim of the present study was to determine the effects of daily short-term exposure to moderate noise on sound level processing in the auditory midbrain. Sound processing properties of auditory midbrain neurons were recorded in anesthetized mice exposed to moderate noise (80 dB SPL, 2 h/d for 6 weeks) and were compared with those from age-matched controls. Neurons in exposed mice had a higher minimum threshold and maximum response intensity, a longer first spike latency, and a higher slope and narrower dynamic range for rate level function. However, these observed changes were greater in neurons with the best frequency within the noise exposure frequency range compared with those outside the frequency range. These sound processing properties also remained abnormal after a 12-week period of recovery in a quiet laboratory environment after completion of noise exposure. In conclusion, even daily short-term exposure to moderate noise can cause long-term impairment of sound level processing in a frequency-specific manner in auditory midbrain neurons. PMID:28589040
Ship noise extends to frequencies used for echolocation by endangered killer whales.
Veirs, Scott; Veirs, Val; Wood, Jason D
2016-01-01
Combining calibrated hydrophone measurements with vessel location data from the Automatic Identification System, we estimate underwater sound pressure levels for 1,582 unique ships that transited the core critical habitat of the endangered Southern Resident killer whales during 28 months between March, 2011, and October, 2013. Median received spectrum levels of noise from 2,809 isolated transits are elevated relative to median background levels not only at low frequencies (20-30 dB re 1 µPa(2)/Hz from 100 to 1,000 Hz), but also at high frequencies (5-13 dB from 10,000 to 96,000 Hz). Thus, noise received from ships at ranges less than 3 km extends to frequencies used by odontocetes. Broadband received levels (11.5-40,000 Hz) near the shoreline in Haro Strait (WA, USA) for the entire ship population were 110 ± 7 dB re 1 µPa on average. Assuming near-spherical spreading based on a transmission loss experiment we compute mean broadband source levels for the ship population of 173 ± 7 dB re 1 µPa 1 m without accounting for frequency-dependent absorption. Mean ship speed was 7.3 ± 2.0 m/s (14.1 ± 3.9 knots). Most ship classes show a linear relationship between source level and speed with a slope near +2 dB per m/s (+1 dB/knot). Spectrum, 1/12-octave, and 1/3-octave source levels for the whole population have median values that are comparable to previous measurements and models at most frequencies, but for select studies may be relatively low below 200 Hz and high above 20,000 Hz. Median source spectrum levels peak near 50 Hz for all 12 ship classes, have a maximum of 159 dB re 1 µPa(2)/Hz @ 1 m for container ships, and vary between classes. Below 200 Hz, the class-specific median spectrum levels bifurcate with large commercial ships grouping as higher power noise sources. Within all ship classes spectrum levels vary more at low frequencies than at high frequencies, and the degree of variability is almost halved for classes that have smaller speed standard deviations. This is the first study to present source spectra for populations of different ship classes operating in coastal habitats, including at higher frequencies used by killer whales for both communication and echolocation.
DNA Damage Levels Determine Cyclobutyl Pyrimidine Dimer Repair Mechanisms in Alfalfa Seedlings.
Quaite, F. E.; Takayanagi, S.; Ruffini, J.; Sutherland, J. C.; Sutherland, B. M.
1994-01-01
Ultraviolet radiation in sunlight damages DNA in plants, but little is understood about the types, lesion capacity, and coordination of repair pathways. We challenged intact alfalfa seedlings with UV doses that induced different initial levels of cyclobutyl pyrimidine dimers and measured repair by excision and photoreactivation. By using alkaline gel electrophoresis of nonradioactive DNAs treated with a cyclobutyl pyrimidine dimer-specific UV endonuclease, we quantitated ethidium-stained DNA by electronic imaging and calculated lesion frequencies from the number average molecular lengths. At low initial dimer frequencies (less than ~30 dimers per million bases), the seedlings used only photoreactivation to repair dimers; excision repair was not significant. At higher damage levels, both excision and photorepair contributed significantly. This strategy would allow plants with low damage levels to use error-free repair requiring only an external light energy source, whereas seedlings subjected to higher damage frequencies could call on additional repair processes requiring cellular energy. Characterization of repair in plants thus requires an investigation of a range of conditions, including the level of initial damage. PMID:12244228
The Potential Effect of Sea Level Rise on Coastal Property Values
NASA Astrophysics Data System (ADS)
O'Donnell, J.
2015-12-01
It is well established that one consequence of increasing global sea level is that the frequency of flooding at low-lying coastal sites will increase. We review recent evidence that the effects coastal geometry will create substantial spatial variations in the changes in flooding frequency with scales of order 100km. Using a simple model of the evolution of coastal property values we demonstrate that a consequence of sea level rise is that the appreciation of coastal properties will peak, and then decline relative to higher properties. The time when the value reach a maximum is shown to depend upon the demand for the coastal property, and the local rate of change of flooding frequency due to sea level rise. The simple model is then extended to include, in an elementary manner, the effects on the value of adjacent but higher properties. We show that the effect of increased flooding frequency of the lower properties leads to an accelerated appreciation of the value of upland properties and an accelerated decline in the value of the coastal properties. We then provide some example calculations for selected sites. We conclude with a discussion of comparisons of the prediction of the analyses to recent data, and then comments on the impact of sea level rise on tax base of coastal communities.
High frequency oscillations in brain hemodynamic response
NASA Astrophysics Data System (ADS)
Akin, Ata; Bolay, Hayrunnisa
2007-07-01
Tight autoregulation of vessel tone guarantees proper delivery of nutrients to the tissues. This regulation is maintained at a more delicate level in the brain since any decrease in the supply of glucose and oxygen to neuronal tissues might lead to unrecoverable injury. Functional near infrared spectroscopy has been proposed as a new tool to monitor the cerebrovascular response during cognitive activity. We have observed that during a Stroop task three distinct oscillatory patterns govern the control of the cerebrovascular reactivity: very low frequency (0.02-0.05 Hz), low frequency (0.08-0.12 Hz) and high frequency (0.12-0.18 Hz). High frequency oscillations have been shown to be related to stress level of the subjects. Our findings indicate that as the stress level is increased so does the energy of the high frequency component indicating a higher stimulation from the autonomic nervous system.
Duggal, Niharika Arora; Pollock, Ross D; Lazarus, Norman R; Harridge, Stephen; Lord, Janet M
2018-04-01
It is widely accepted that aging is accompanied by remodelling of the immune system including thymic atrophy and increased frequency of senescent T cells, leading to immune compromise. However, physical activity, which influences immunity but declines dramatically with age, is not considered in this literature. We assessed immune profiles in 125 adults (55-79 years) who had maintained a high level of physical activity (cycling) for much of their adult lives, 75 age-matched older adults and 55 young adults not involved in regular exercise. The frequency of naïve T cells and recent thymic emigrants (RTE) were both higher in cyclists compared with inactive elders, and RTE frequency in cyclists was no different to young adults. Compared with their less active counterparts, the cyclists had significantly higher serum levels of the thymoprotective cytokine IL-7 and lower IL-6, which promotes thymic atrophy. Cyclists also showed additional evidence of reduced immunesenescence, namely lower Th17 polarization and higher B regulatory cell frequency than inactive elders. Physical activity did not protect against all aspects of immunesenescence: CD28 -ve CD57 +ve senescent CD8 T-cell frequency did not differ between cyclists and inactive elders. We conclude that many features of immunesenescence may be driven by reduced physical activity with age. © 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.
Boyer, Elizabeth R; Patterson, Aleksys
2018-05-05
Trips and falls are common concerns reported by parents of children with cerebral palsy. Specific gait pathologies (excessive internal hip rotation, intoeing, and stiff knee gait) are anecdotally associated with higher rates of falls. Is fall frequency higher for the aforementioned gait pathologies? Parent-reported fall frequency from 1063 children with cerebral palsy who also had a three-dimensional gait analysis was retrospectively reviewed. Frequency of 10 common gait pathologies was determined and fall frequency for the gait pathologies of interest were compared to matched control groups. Possible effects of Gross Motor Functional Classification System (GMFCS) level and age on fall frequency were also assessed and matched in the control group, as appropriate. In general, parent-reported fall frequency increased from GMFCS level I to II and then decreased until level IV. Moreover, younger children tended to report greater fall frequency, though children who reported never falling were of similar age as those who reported weekly falls, resulting in an inverted-U shaped relationship. Children with cerebral palsy who walked with excessive internal hip rotation, excessive intoeing, or stiff knee gait did not report increased fall frequencies compared to other children with cerebral palsy matched on GMFCS level and age that did not walk with those gait patterns. Approximately 35% of children reported never falling, 35% reported falling daily, and 30% reported falling monthly or weekly for each gait pattern. Therefore, elevated fall frequency appears to be a generic problem for most children with CP rather than a function of a specific gait pattern. Clinicians should be aware of these relationships, or lack thereof, when trying to decipher the cause of a child's falling and when determining appropriate interventions. Future studies may seek to more objectively quantify fall frequency, as self-report is the main limitation of this study. Copyright © 2018 Elsevier B.V. All rights reserved.
Frequency response of portable PEF meters.
Hankinson, J L; Das, M K
1995-08-01
Peak expiratory flow (PEF) is a dynamic parameter and therefore requires a measuring device with a high-frequency response. This study evaluated the frequency-response characteristics of eight commercially available PEF meters, using simulated forced-expiratory maneuvers with a computer-controlled mechanical pump. Three different PEF levels were used (200, 400, and 600 L/min) at six levels of harmonic-frequency content similar to those observed in human subjects. For waveforms with higher frequency content (at the high end or above the physiologic range), the Assess, Vitalograph, Pocket Peak, and Spir-O-Flow PEF meters all overread PEF (greater than 15% difference from target values) at all three PEF levels. These results suggest that the frequency response of PEF meters is an important consideration in the selection of such meters and should be included in device requirements. The current practice of using various levels of American Thoracic Society (ATS) waveform 24 with its low-frequency content may not adequately evaluate the frequency characteristics of PEF meters. An upper range (5% of the fundamental frequency) of 12 Hz, within the range observed in normal subjects, appears to be more practical than an upper limit of 20 Hz.
ERIC Educational Resources Information Center
Malecki, Christine Kerres; Demaray, Michelle Kilpatrick; Coyle, Samantha; Geosling, Raymond; Rueger, Sandra Yu; Becker, Lisa Davidson
2015-01-01
Background: Bullying behavior is related to higher levels of internalizing distress and can be defined as including three aspects: frequency, intentionality, and power differential. However, bullying behavior is most often measured using only one aspect: frequency. Objective: The current study investigated the relative importance of several…
Gacek, Maria
2014-03-01
The aim of this study was to analyze selected individual determinants of consumption of soy products and legumes by menopausal women. The analyzed individual characteristics included the level of general self-efficacy, optimism, and satisfaction with life. The study, using a questionnaire for the assessment of food product consumption frequency, and psychological tests (GSES, LOT-R, SWLS), was conducted in a group of 320 women aged between 45 and 55 years. Spearman's coefficient of rank correlation and the Kruskal-Wallis test with the Dunn test for multiple comparisons were used for statistical analysis (p < 0.05). The analyzed 45-55-year-old women consumed legume seeds several times a month on average, while the frequency of soy/soy product consumption was lower than once a month. Statistical analysis revealed that the frequency of soy product consumption increased with the level of self-efficacy, optimism and satisfaction with life (p < 0.01). Also the increased frequency of legume seed consumption was associated with higher level of optimism and satisfaction with life (p < 0.01). Intergroup comparisons of the average consumption frequency of these products confirmed that legume seeds were significantly more frequently chosen by women characterized by high rather than low levels of optimism (3.36 vs. 2.62, p < 0.001) and satisfaction with life (3.36 vs. 2.65, p < 0.01). Also soy products were preferred significantly more often by women with higher levels of optimism (2.00 vs. 1.38, p < 0.05) and satisfaction with life (2.02 vs. 1.39, p < 0.05). The consumption of legume seeds, and especially soy products, was revealed to be very low among perimenopausal women, and varied depending on the analyzed individual traits, with a tendency to more frequent ingestion by individuals with higher levels of self-efficacy, optimism, and satisfaction with life.
The Effect of Descriptive Norms on Pregaming Frequency: Tests of Five Moderators.
Merrill, Jennifer E; Kenney, Shannon R; Carey, Kate B
2016-07-02
Pregaming is highly prevalent on college campuses and associated with heightened levels of intoxication and risk of alcohol consequences. However, research examining the correlates of pregaming behavior is limited. Descriptive norms (i.e., perceptions about the prevalence or frequency of a behavior) are reliable and comparatively strong predictors of general drinking behavior, with recent evidence indicating that they are also associated with pregaming. We tested the hypothesis that higher descriptive norms for pregaming frequency would be associated with personal pregaming frequency. We also tested whether this effect would be stronger in the context of several theory-based moderators: female gender, higher injunctive norms (i.e., perceptions of others' attitudes toward a particular behavior), a more positive attitude toward pregaming, a stronger sense of identification with the drinking habits of other students, and stronger social comparison tendencies. College student drinkers (N = 198, 63% female) participated in an online survey assessing frequency of pregaming, descriptive norms, and hypothesized moderators. A multiple regression model revealed that higher descriptive norms, a more positive attitude toward pregaming, and stronger peer identification were significantly associated with greater pregaming frequency among drinkers. However, no moderators of the association between descriptive norms and pregaming frequency were observed. Descriptive norms are robust predictors of pregaming behavior, for both genders and across levels of several potential moderators. Future research seeking to understand pregaming behavior should consider descriptive norms, as well as personal attitudes and identification with student peers, as targets of interventions designed to reduce pregaming.
Glacial versus interglacial sedimentation rates and turbidite frequency in the Bahamas
NASA Astrophysics Data System (ADS)
Droxler, Andre W.; Schlager, Wolfgang
1985-11-01
The southern Tongue of the Ocean is a 1300-m-deep, flat-floored basin in the Bahamas that receives large amounts of sediment from the carbonate platforms surrounding it on three sides. We have examined five 8 13-m-long piston cores and determined bulk sedimentation rates, turbidite frequency, and turbidite accumulation rates for the past two glacial and interglacial periods. The mean of bulk sedimentation rates is four to six times higher in interglacial periods; average accumulation rates of recognizable turbidites are higher by a factor of 21 to 45, and interglacial turbidite frequency is higher by a factor of 6 to 14. Sediment composition indicates that increased interglacial rates are due to higher accumulation of platform-derived material. Additional data from other Bahamian basins as well as published material from the Caribbean strongly suggest that highstand shedding is a general trend in pure carbonate depositional systems. Carbonate platforms without a siliciclastic component export more material during highstands of sea level when the platform tops are flooded and produce sediment. The response of carbonate platforms to Quaternary sea-level cycles is opposed to that of siliciclastic ocean margins, where sediment is stored on the inner shelf during highstands and passed on to continental rises and abyssal plains during lowstands of sea level.
Kathiria, Palak; Sidler, Corinne; Golubov, Andrey; Kalischuk, Melanie; Kawchuk, Lawrence M.; Kovalchuk, Igor
2010-01-01
Our previous experiments showed that infection of tobacco (Nicotiana tabacum) plants with Tobacco mosaic virus (TMV) leads to an increase in homologous recombination frequency (HRF). The progeny of infected plants also had an increased rate of rearrangements in resistance gene-like loci. Here, we report that tobacco plants infected with TMV exhibited an increase in HRF in two consecutive generations. Analysis of global genome methylation showed the hypermethylated genome in both generations of plants, whereas analysis of methylation via 5-methyl cytosine antibodies demonstrated both hypomethylation and hypermethylation. Analysis of the response of the progeny of infected plants to TMV, Pseudomonas syringae, or Phytophthora nicotianae revealed a significant delay in symptom development. Infection of these plants with TMV or P. syringae showed higher levels of induction of PATHOGENESIS-RELATED GENE1 gene expression and higher levels of callose deposition. Our experiments suggest that viral infection triggers specific changes in progeny that promote higher levels of HRF at the transgene and higher resistance to stress as compared with the progeny of unstressed plants. However, data reported in these studies do not establish evidence of a link between recombination frequency and stress resistance. PMID:20498336
The Prevalence of Annoyance and Effects after Long-Term Exposure to Low-Frequency Noise
NASA Astrophysics Data System (ADS)
PERSSON WAYE, K.; RYLANDER, R.
2001-02-01
A cross-sectional questionnaire and noise measurement survey was undertaken among 279 randomly chosen persons exposed to noise from heat pump/ventilation installations in their homes. The aim was to evaluate the prevalence of annoyance, disturbance of rest and concentration and the presence of psycho-social and medical symptoms in relation to noise exposure. Of the sample, 108 persons were exposed to a noise classified as of a low-frequency character (low-frequency noise exposed). As controls were chosen 171 persons living in similar residential areas, but exposed to a noise classified as of a mid-frequency character. The results showed that the prevalence of annoyance and disturbed concentration and rest was significantly higher among the persons exposed to low-frequency noise as compared to controls. Annoyance was suggested to be related to the sound pressure levels of the dominant low frequencies. The dB (A) noise levels did not predict annoyance. No significant differences in medical or psycho-social symptoms were found between the low-frequency noise exposed persons and controls. Among persons reporting themselves to be “rather” or “very” annoyed by low-frequency noise due to the heat pump/ventilation installations, a higher extent of psycho-social symptoms, sleep disturbance and headaches was found.
Pérez-Hernández, Bibiana; García-Esquinas, Esther; Graciani, Auxiliadora; Guallar-Castillón, Pilar; López-García, Esther; León-Muñoz, Luz M; Banegas, José R; Rodríguez-Artalejo, Fernando
2017-03-01
To examine the distribution of the main cardiovascular risk factors (CVRF) according to socioeconomic level (SEL) among older adults in Spain. A cross-sectional study conducted in 2008-2010 with 2699 individuals representative of the noninstitutionalized Spanish population aged ≥ 60 years. Socioeconomic level was assessed using educational level, occupation, and father's occupation. The CVRF included behavioral and biological factors and were measured under standardized conditions. In age- and sex-adjusted analyses, higher educational level was associated with a higher frequency of moderate alcohol consumption and leisure time physical activity, and less time spent watching television. An inverse educational gradient was observed for frequency of obesity (odds ratio [OR] in university vs primary level or below education, 0.44; 95% confidence interval [95%CI], 0.33-0.57; P-trend < .01), metabolic syndrome (OR = 0.56; 95%CI, 0.43-0.71; P-trend < .01), diabetes (OR = 0.68; 95%CI, 0.49-0.95; P-trend < .05), and cardiovascular disease (OR = 0.52; 95%CI, 0.29-0.91; P-trend < .05). Compared with a nonmanual occupation, having a manual occupation was associated with a higher frequency of several CVRF; this association was stronger than that observed for father's occupation. Differences in CVRF across SELs were generally greater in women than in men. There are significant social inequalities in CVRF among older adults in Spain. Reducing these inequalities, bringing the levels of CVRF in those from lower SEL in line with the levels seen in higher SEL, could substantially reduce the prevalence of CVRF in the older adult population. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Bo; Zhao, Hongwei, E-mail: hwzhao@jlu.edu.cn, E-mail: khl69@163.com; Zhao, Dan
It has always been a critical issue to understand the material removal behavior of Vibration-Assisted Machining (VAM), especially on atomic level. To find out the effects of vibration frequency on material removal response, a three-dimensional molecular dynamics (MD) model has been established in this research to investigate the effects of scratched groove, crystal defects on the surface quality, comparing with the Von Mises shear strain and tangential force in simulations during nano-scratching process. Comparisons are made among the results of simulations from different vibration frequency with the same scratching feed, depth, amplitude and crystal orientation. Copper potential in this simulationmore » is Embedded-Atom Method (EAM) potential. Interaction between copper and carbon atoms is Morse potential. Simulational results show that higher frequency can make groove smoother. Simulation with high frequency creates more dislocations to improve the machinability of copper specimen. The changing frequency does not have evident effects on Von Mises shear strain. Higher frequency can decrease the tangential force to reduce the consumption of cutting energy and tool wear. In conclusion, higher vibration frequency in VAM on mono-crystalline copper has positive effects on surface finish, machinablility and tool wear reduction.« less
Unbuckling the Bible Belt: A State-Level Analysis of Religious Factors and Google Searches for Porn.
Whitehead, Andrew L; Perry, Samuel L
2018-01-01
While the link between individual religious characteristics and pornography consumption is well established, relatively little research has considered how the wider religious context may influence pornography use. Exceptions in the literature to date have relied on relatively broad, subjective measures of religious commitment, largely ignoring issues of religious belonging, belief, or practice. This study moves the conversation forward by examining how a variety of state-level religious factors predict Google searches for the term porn, net of relevant sociodemog raphic and ideological controls. Our multivariate findings indicate that higher percentages of Evangelical Protestants, theists, and biblical literalists in a state predict higher frequencies of searching for porn, as do higher church attendance rates. Conversely, higher percentages of religiously unaffiliated persons in a state predict lower frequencies of searching for porn. Higher percentages of total religious adherents, Catholics, or mainline Protestants in a state are unrelated to searching for porn with controls in place. Contrary to recent research, our analyses also show that higher percentages of political conservatives in a state predicted lower frequencies of porn searches. Our findings support theories that more salient, traditional religious influences in a state may influence residents-whether religious or not-toward more covert sexual experiences.
Routine cognitive errors: a trait-like predictor of individual differences in anxiety and distress.
Fetterman, Adam K; Robinson, Michael D
2011-02-01
Five studies (N=361) sought to model a class of errors--namely, those in routine tasks--that several literatures have suggested may predispose individuals to higher levels of emotional distress. Individual differences in error frequency were assessed in choice reaction-time tasks of a routine cognitive type. In Study 1, it was found that tendencies toward error in such tasks exhibit trait-like stability over time. In Study 3, it was found that tendencies toward error exhibit trait-like consistency across different tasks. Higher error frequency, in turn, predicted higher levels of negative affect, general distress symptoms, displayed levels of negative emotion during an interview, and momentary experiences of negative emotion in daily life (Studies 2-5). In all cases, such predictive relations remained significant with individual differences in neuroticism controlled. The results thus converge on the idea that error frequency in simple cognitive tasks is a significant and consequential predictor of emotional distress in everyday life. The results are novel, but discussed within the context of the wider literatures that informed them. © 2010 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business
Goodman, Shawn S; Keefe, Douglas H
2006-06-01
Otoacoustic emissions serve as a noninvasive probe of the medial olivocochlear (MOC) reflex. Stimulus frequency otoacoustic emissions (SFOAEs) elicited by a low-level probe tone may be the optimal type of emission for studying MOC effects because at low levels, the probe itself does not elicit the MOC reflex [Guinan et al. (2003) J. Assoc. Res. Otolaryngol. 4:521]. Based on anatomical considerations, the MOC reflex activated by ipsilateral acoustic stimulation (mediated by the crossed olivocochlear bundle) is predicted to be stronger than the reflex to contralateral stimulation. Broadband noise is an effective activator of the MOC reflex; however, it is also an effective activator of the middle-ear muscle (MEM) reflex, which can make results difficult to interpret. The MEM reflex may be activated at lower levels than measured clinically, and most previous human studies have not explicitly included measurements to rule out MEM reflex contamination. The current study addressed these issues using a higher-frequency SFOAE probe tone to test for cochlear changes mediated by the MOC reflex, while simultaneously monitoring the MEM reflex using a low-frequency probe tone. Broadband notched noise was presented ipsilaterally at various levels to elicit probe-tone shifts. Measurements are reported for 15 normal-hearing subjects. With the higher-frequency probe near 1.5 kHz, only 20% of subjects showed shifts consistent with an MOC reflex in the absence of an MEM-induced shift. With the higher-frequency probe near 3.5 kHz, up to 40% of subjects showed shifts in the absence of an MEM-induced shift. However, these responses had longer time courses than expected for MOC-induced shifts, and may have been dominated by other cochlear processes, rather than MOC reflex. These results suggest caution in the interpretation of effects observed using ipsilaterally presented acoustic activators intended to excite the MOC reflex.
Higher songs of city birds may not be an individual response to noise.
Zollinger, Sue Anne; Slater, Peter J B; Nemeth, Erwin; Brumm, Henrik
2017-08-16
It has been observed in many songbird species that populations in noisy urban areas sing with a higher minimum frequency than do matched populations in quieter, less developed areas. However, why and how this divergence occurs is not yet understood. We experimentally tested whether chronic noise exposure during vocal learning results in songs with higher minimum frequencies in great tits ( Parus major ), the first species for which a correlation between anthropogenic noise and song frequency was observed. We also tested vocal plasticity of adult great tits in response to changing background noise levels by measuring song frequency and amplitude as we changed noise conditions. We show that noise exposure during ontogeny did not result in songs with higher minimum frequencies. In addition, we found that adult birds did not make any frequency or song usage adjustments when their background noise conditions were changed after song crystallization. These results challenge the common view of vocal adjustments by city birds, as they suggest that either noise itself is not the causal force driving the divergence of song frequency between urban and forest populations, or that noise induces population-wide changes over a time scale of several generations rather than causing changes in individual behaviour. © 2017 The Author(s).
Field hearing measurements of the Atlantic sharpnose shark Rhizoprionodon terraenovae.
Casper, B M; Mann, D A
2009-12-01
Field measurements of hearing thresholds were obtained from the Atlantic sharpnose shark Rhizoprionodon terraenovae using the auditory evoked potential method (AEP). The fish had most sensitive hearing at 20 Hz, the lowest frequency tested, with decreasing sensitivity at higher frequencies. Hearing thresholds were lower than AEP thresholds previously measured for the nurse shark Ginglymostoma cirratum and yellow stingray Urobatis jamaicensis at frequencies <200 Hz, and similar at 200 Hz and above. Rhizoprionodon terraenovae represents the closest comparison in terms of pelagic lifestyle to the sharks which have been observed in acoustic field attraction experiments. The sound pressure levels that would be equivalent to the particle acceleration thresholds of R. terraenovae were much higher than the sound levels which attracted closely related sharks suggesting a discrepancy between the hearing threshold experiments and the field attraction experiments.
Does Serum Homocysteine Explain the Connection Between Sexual Frequency and Cardiovascular Risk?
Yang, Hui-Fang; Kao, Tung-Wei; Lin, Yuan-Yung; Shih, Mu-Tsun; Wu, Li-Wei; Liaw, Fang-Yih; Peng, Tao-Chun; Chen, Wei-Liang
2017-07-01
Sexual activity correlates with various health issues, and homocysteine is considered an independent risk factor for cardiovascular events and atherosclerosis. Research on the relation of sexual activity to sexual frequency and homocysteine is sparse. To examine the association between sexual frequency and homocysteine in the general population in the United States. In total, 2,267 eligible participants 20 to 59 years old who had serum homocysteine data and completed a sexual behavior questionnaire were enrolled from the National Health and Nutrition Examination Survey of 2005 to 2006. The correlation between sexual frequency and serum homocysteine levels was analyzed using a linear regression model and an extended-model approach was performed for covariate adjustment. Individuals, especially men, in the lower quartiles of sexual frequency had significantly higher serum homocysteine levels, and a sex difference was identified in subgroup analysis. In a model of quartile-based analysis after adjustment for age, sex, and race and ethnicity, the regression coefficient of the highest quartile of sexual frequency compared with the lowest quartile was -1.326 (P = .012). After further adjustment for multiple covariates, the inverse association between sexual frequency and serum homocysteine levels remained unchanged. Negative trends maintained statistical significance (P for trend < .05). In subgroup analysis by sex, a negative association between sexual frequency and serum homocysteine levels remained unchanged in men even after adjusting for multiple covariates, but not in women. Clinical physicians in primary care should support patients' sexual activity, and there are implications for health promotion programs. This is the first observational investigation stratified by sex to evaluate the correlation between sexual frequency and serum homocysteine levels. The study was a cross-sectional observational investigation and the causal relation should be evaluated in a follow-up study. Decreased sexual frequency correlated with higher homocysteine levels in a nationally representative sample of US adults, especially men; this might increase the risk of cardiovascular disease or other atherothrombotic events. Yang H-F, Kao T-W, Lin Y-Y, et al. Does Serum Homocysteine Explain the Connection Between Sexual Frequency and Cardiovascular Risk? J Sex Med 2017;14:910-917. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Wang, Qian; He, An M; Gao, Bo; Chen, Lan; Yu, Qiang Z; Guo, Huan; Shi, Bin J; Jiang, Pu; Zhang, Zeng Y; Li, Ping L; Sheng, Ying G; Fu, Mo J; Wu, Chun T; Chen, Min X; Yuan, Jing
2011-01-01
In recent years, adverse health effects of chemicals from electronic waste (e-waste) have been reported. However, little is known about the genotoxic effects of chemicals in e-waste. In the present study, air concentrations of the toxic metals at e-waste and control sites were analyzed using inductively-coupled plasma mass spectrometry. Levels of toxic metals (lead, copper and cadmium) in blood and urine were detected using atomic absorption spectrophotometry in 48 exposed individuals and 56 age- and sex-matched controls. The frequencies of lymphocytic micronucleated binucleated cells (MNBNCs) were determined using a cytokinesis-block micronucleus assay. Results indicated that blood lead levels were significantly higher in the exposed group (median: 11.449 μg/dL, 1st/3rd quartiles: 9.351-14.410 μg/dL) than in the control group (median: 9.104 μg/dL, 1st/3rd quartiles: 7.275-11.389 μg/dL). The exposed group had higher MNBNCs frequencies (median: 4.0 per thousand, 1st/3rd quartiles: 2.0-7.0 per thousand) compared with the controls (median: 1.0 per thousand, 1st/3rd quartiles: 0.0-2.0 per thousand). Additionally, MNBNCs frequencies and blood lead levels were positively correlated (r = 0.254, p<0.01). Further analysis suggested that a history of working with e-waste was a predictor for increased blood lead levels and MNBNCs frequencies in the subjects. The results suggest that both the living and occupational environments at the e-waste site may be risk factors for increased MNBNCs frequencies among those who are exposed.
Evaluation of the DSM-5 Severity Indicator for Bulimia Nervosa
Grilo, Carlos M.; Ivezaj, Valentina; White, Marney A.
2015-01-01
This study examined the DSM-5 severity criterion for bulimia nervosa (BN) based on the frequency of inappropriate weight compensatory behaviors. 199 community volunteers classified with BN were categorized using DSM-5 severity levels and compared on demographic and clinical variables. 77 (39%) participants were categorized as mild, 68 (34%) as moderate, 32 (16%) as severe, and 22 (11%) as extreme. The severity groups did not differ significantly in demographic variables or body mass index. Shape and Weight concerns did not differ significantly across severity groups. Binge eating differed with the extreme group having higher frequency than the severe, moderate, and mild groups, which did not differ from each other. Restraint differed with the extreme group having significantly higher levels than the mild group. Eating concerns differed with the extreme group having higher levels than moderate and mild groups. Depression differed with the extreme group having higher levels than severe, moderate, and mild groups, which did not differ from each other. Findings from this non-clinical group provide new, albeit modest, support for DSM-5 severity rating for BN based on frequency of inappropriate weight compensatory behaviors. Statistical findings indicate that differences in collateral clinical variables associated with the DSM-5 severity ratings reflect small effect sizes. Further research is needed with treatment-seeking patient groups with BN to establish the validity of the DSM-5 severity specifier and should include broader clinical and functional validators. PMID:25744910
Evaluation of the DSM-5 severity indicator for bulimia nervosa.
Grilo, Carlos M; Ivezaj, Valentina; White, Marney A
2015-04-01
This study examined the DSM-5 severity criterion for bulimia nervosa (BN) based on the frequency of inappropriate weight compensatory behaviors. 199 community volunteers classified with BN were categorized using DSM-5 severity levels and compared on demographic and clinical variables. 77 (39%) participants were categorized as mild, 68 (34%) as moderate, 32 (16%) as severe, and 22 (11%) as extreme. The severity groups did not differ significantly in demographic variables or body mass index. Shape and Weight concerns did not differ significantly across severity groups. Binge eating differed with the extreme group having significantly higher frequency than the severe, moderate, and mild groups, which did not differ from each other. Restraint differed with the extreme group having significantly higher levels than the mild group. Eating concerns differed with the extreme group having significantly higher levels than moderate and mild groups. Depression differed with the extreme group having significantly higher levels than severe, moderate, and mild groups, which did not differ from each other. Findings from this non-clinical group provide new, albeit modest, support for DSM-5 severity rating for BN based on frequency of inappropriate weight compensatory behaviors. Statistical findings indicate that differences in collateral clinical variables associated with the DSM-5 severity ratings reflect small effect sizes. Further research is needed with treatment-seeking patient groups with BN to establish the validity of the DSM-5 severity specifier and should include broader clinical and functional validators. Copyright © 2015 Elsevier Ltd. All rights reserved.
Almeida, Andre; George, David; Smith, John; Wolfe, Joe
2013-09-01
Using an automated clarinet playing system, the frequency f, sound level L, and spectral characteristics are measured as functions of blowing pressure P and the force F applied by the mechanical lip at different places on the reed. The playing regime on the (P,F) plane lies below an extinction line F(P) with a negative slope of a few square centimeters and above a pressure threshold with a more negative slope. Lower values of F and P can produce squeaks. Over much of the playing regime, lines of equal frequency have negative slope. This is qualitatively consistent with passive reed behavior: Increasing F or P gradually closes the reed, reducing its equivalent acoustic compliance, which increases the frequency of the peaks of the parallel impedance of bore and reed. High P and low F produce the highest sound levels and stronger higher harmonics. At low P, sound level can be increased at constant frequency by increasing P while simultaneously decreasing F. At high P, where lines of equal f and of equal L are nearly parallel, this compensation is less effective. Applying F further from the mouthpiece tip moves the playing regime to higher F and P, as does a stiffer reed.
Real-Time Classification of Exercise Exertion Levels Using Discriminant Analysis of HRV Data.
Jeong, In Cheol; Finkelstein, Joseph
2015-01-01
Heart rate variability (HRV) was shown to reflect activation of sympathetic nervous system however it is not clear which set of HRV parameters is optimal for real-time classification of exercise exertion levels. There is no studies that compared potential of two types of HRV parameters (time-domain and frequency-domain) in predicting exercise exertion level using discriminant analysis. The main goal of this study was to compare potential of HRV time-domain parameters versus HRV frequency-domain parameters in classifying exercise exertion level. Rest, exercise, and recovery categories were used in classification models. Overall 79.5% classification agreement by the time-domain parameters as compared to overall 52.8% classification agreement by frequency-domain parameters demonstrated that the time-domain parameters had higher potential in classifying exercise exertion levels.
Zhu, Lingyu; Ji, Shengchang; Shen, Qi; Liu, Yuan; Li, Jinyu; Liu, Hao
2013-01-01
The capacitors in high-voltage direct-current (HVDC) converter stations radiate a lot of audible noise which can reach higher than 100 dB. The existing noise level prediction methods are not satisfying enough. In this paper, a new noise level prediction method is proposed based on a frequency response function considering both electrical and mechanical characteristics of capacitors. The electro-mechanical frequency response function (EMFRF) is defined as the frequency domain quotient of the vibration response and the squared capacitor voltage, and it is obtained from impulse current experiment. Under given excitations, the vibration response of the capacitor tank is the product of EMFRF and the square of the given capacitor voltage in frequency domain, and the radiated audible noise is calculated by structure acoustic coupling formulas. The noise level under the same excitations is also measured in laboratory, and the results are compared with the prediction. The comparison proves that the noise prediction method is effective. PMID:24349105
Zhu, Lingyu; Ji, Shengchang; Shen, Qi; Liu, Yuan; Li, Jinyu; Liu, Hao
2013-01-01
The capacitors in high-voltage direct-current (HVDC) converter stations radiate a lot of audible noise which can reach higher than 100 dB. The existing noise level prediction methods are not satisfying enough. In this paper, a new noise level prediction method is proposed based on a frequency response function considering both electrical and mechanical characteristics of capacitors. The electro-mechanical frequency response function (EMFRF) is defined as the frequency domain quotient of the vibration response and the squared capacitor voltage, and it is obtained from impulse current experiment. Under given excitations, the vibration response of the capacitor tank is the product of EMFRF and the square of the given capacitor voltage in frequency domain, and the radiated audible noise is calculated by structure acoustic coupling formulas. The noise level under the same excitations is also measured in laboratory, and the results are compared with the prediction. The comparison proves that the noise prediction method is effective.
Hareuveny, Ronen; Sudan, Madhuri; Halgamuge, Malka N; Yaffe, Yoav; Tzabari, Yuval; Namir, Daniel; Kheifets, Leeka
2015-01-30
This study characterizes extremely low frequency (ELF) magnetic field (MF) levels in 10 car models. Extensive measurements were conducted in three diesel, four gasoline, and three hybrid cars, under similar controlled conditions and negligible background fields. Averaged over all four seats under various driving scenarios the fields were lowest in diesel cars (0.02 μT), higher for gasoline (0.04-0.05 μT) and highest in hybrids (0.06-0.09 μT), but all were in-line with daily exposures from other sources. Hybrid cars had the highest mean and 95th percentile MF levels, and an especially large percentage of measurements above 0.2 μT. These parameters were also higher for moving conditions compared to standing while idling or revving at 2500 RPM and higher still at 80 km/h compared to 40 km/h. Fields in non-hybrid cars were higher at the front seats, while in hybrid cars they were higher at the back seats, particularly the back right seat where 16%-69% of measurements were greater than 0.2 μT. As our results do not include low frequency fields (below 30 Hz) that might be generated by tire rotation, we suggest that net currents flowing through the cars' metallic chassis may be a possible source of MF. Larger surveys in standardized and well-described settings should be conducted with different types of vehicles and with spectral analysis of fields including lower frequencies due to magnetization of tires.
Ship noise extends to frequencies used for echolocation by endangered killer whales
Veirs, Val; Wood, Jason D.
2016-01-01
Combining calibrated hydrophone measurements with vessel location data from the Automatic Identification System, we estimate underwater sound pressure levels for 1,582 unique ships that transited the core critical habitat of the endangered Southern Resident killer whales during 28 months between March, 2011, and October, 2013. Median received spectrum levels of noise from 2,809 isolated transits are elevated relative to median background levels not only at low frequencies (20–30 dB re 1 µPa2/Hz from 100 to 1,000 Hz), but also at high frequencies (5–13 dB from 10,000 to 96,000 Hz). Thus, noise received from ships at ranges less than 3 km extends to frequencies used by odontocetes. Broadband received levels (11.5–40,000 Hz) near the shoreline in Haro Strait (WA, USA) for the entire ship population were 110 ± 7 dB re 1 µPa on average. Assuming near-spherical spreading based on a transmission loss experiment we compute mean broadband source levels for the ship population of 173 ± 7 dB re 1 µPa 1 m without accounting for frequency-dependent absorption. Mean ship speed was 7.3 ± 2.0 m/s (14.1 ± 3.9 knots). Most ship classes show a linear relationship between source level and speed with a slope near +2 dB per m/s (+1 dB/knot). Spectrum, 1/12-octave, and 1/3-octave source levels for the whole population have median values that are comparable to previous measurements and models at most frequencies, but for select studies may be relatively low below 200 Hz and high above 20,000 Hz. Median source spectrum levels peak near 50 Hz for all 12 ship classes, have a maximum of 159 dB re 1 µPa2/Hz @ 1 m for container ships, and vary between classes. Below 200 Hz, the class-specific median spectrum levels bifurcate with large commercial ships grouping as higher power noise sources. Within all ship classes spectrum levels vary more at low frequencies than at high frequencies, and the degree of variability is almost halved for classes that have smaller speed standard deviations. This is the first study to present source spectra for populations of different ship classes operating in coastal habitats, including at higher frequencies used by killer whales for both communication and echolocation. PMID:27004149
Knobel, Mark; Finkbeiner, Matthew; Caramazza, Alfonso
2008-03-01
The effect of lexical frequency on language-processing tasks is exceptionally reliable. For example, pictures with higher frequency names are named faster and more accurately than those with lower frequency names. Experiments with normal participants and patients strongly suggest that this production effect arises at the level of lexical access. Further work has suggested that within lexical access this effect arises at the level of lexical representations. Here we present patient E.C. who shows an effect of lexical frequency on his nonword error rate. The best explanation of his performance is that there is an additional locus of frequency at the interface of lexical and segmental representational levels. We confirm this hypothesis by showing that only computational models with frequency at this new locus can produce a similar error pattern to that of patient E.C. Finally, in an analysis of a large group of Italian patients, we show that there exist patients who replicate E.C.'s pattern of results and others who show the complementary pattern of frequency effects on semantic error rates. Our results combined with previous findings suggest that frequency plays a role throughout the process of lexical access.
The Effect of Descriptive Norms on Pregaming Frequency: Tests of Five Moderators
Merrill, Jennifer E.; Kenney, Shannon R.; Carey, Kate B.
2016-01-01
Background Pregaming is highly prevalent on college campuses and associated with heightened levels of intoxication and risk of alcohol consequences. However, research examining the correlates of pregaming behavior is limited. Descriptive norms (i.e., perceptions about the prevalence or frequency of a behavior) are reliable and comparatively strong predictors of general drinking behavior, with recent evidence indicating that they are also associated with pregaming. Objectives We tested the hypothesis that higher descriptive norms for pregaming frequency would be associated with personal pregaming frequency. We also tested whether this effect would be stronger in the context of several theory-based moderators: female gender, higher injunctive norms (i.e., perceptions of others' attitudes toward a particular behavior), a more positive attitude toward pregaming, a stronger sense of identification with the drinking habits of other students, and stronger social comparison tendencies. Methods College student drinkers (N=198, 63% female) participated in an online survey assessing frequency of pregaming, descriptive norms, and hypothesized moderators. Results A multiple regression model revealed that higher descriptive norms, a more positive attitude toward pregaming, and stronger peer identification were significantly associated with greater pregaming frequency among drinkers. However, no moderators of the association between descriptive norms and pregaming frequency were observed. Conclusions/Importance Descriptive norms are robust predictors of pregaming behavior, for both genders and across levels of several potential moderators. Future research seeking to understand pregaming behavior should consider descriptive norms, as well as personal attitudes and identification with student peers, as targets of interventions designed to reduce pregaming. PMID:27070494
Colón-Ramos, Uriyoán; Pérez-Cardona, Cynthia M.; Monge-Rojas, Rafael
2014-01-01
Objective To identify socio-demographic, behavioral, and health-related correlates of food preferences in Puerto Rico that will help determine Caribbean-region populations vulnerable to nutrition transition. Methods Data from a cross-sectional study of a representative sample of 858 adults residing in the San Juan Metropolitan Area of Puerto Rico were analyzed. Multivariable ordinal logistic regressions were used to model the frequency of consumption of 1) fruits and vegetables, 2) tubers/starchy root vegetables, 3) fried foods, and 4) Western-style fast foods as a function of socio-demographic, behavioral, and health-related characteristics. Results Higher frequency of consumption of fruits and vegetables was associated with being physically active and older and having a medium to high level of education, whereas intake of tubers was associated with being older, having a low income, not using government insurance, and having elevated levels of triglycerides. Frequency of consumption of fast food was associated with younger age, higher income, 12–15 years of formal education, and a higher body mass index (BMI), whereas frequency of consumption of fried food was associated with being younger and male, not being a smoker, and having elevated levels of fasting blood glucose. Conclusions The results indicate a nutrition transition in Puerto Rico with health consequences for the Caribbean region. The characteristics of this nutrition transition seem to be determined by income, education, and age, but may also be dictated by access to various food groups. These results set the stage for needed investigation of environmental and individual-level factors that could shape patterns in food consumption. PMID:24553760
Demircigil, Gonca Çakmak; Erdem, Onur; Gaga, Eftade O; Altuğ, Hicran; Demirel, Gülçin; Özden, Özlem; Arı, Akif; Örnektekin, Sermin; Döğeroğlu, Tuncay; van Doorn, Wim; Burgaz, Sema
2014-01-01
There is an increasing attempt in the world to determine the exposures of children to environmental chemicals. To analyze the genotoxic effect of air pollution, micronucleus (MN) assay was carried out in buccal epithelial cells (BECs) of children living in an urban city of Turkey. Children from two schools at urban-traffic and suburban sites were investigated in summer and winter seasons for the determination of BEC-MN frequency (per mille) and frequency of BEC with MN (per mille). The same children were also recruited for lung function measurements within a MATRA project ("Together Towards Clean Air in Eskisehir and Iskenderun") Measured NO2 and SO2 concentrations did not exceed the European Union (EU) limit levels either in urban-traffic or suburban regions. Higher O3 concentrations were measured in the suburban site especially in the summer period. Particulate matter (PM2.5 and PM10) levels which did not differ statistically between two regions were above the EU limits in general. Although BEC-MN frequencies of children living in the suburban sites were higher in general, the difference between two regions was not significant either in the summer or winter periods. BEC-MN frequencies of the urban-traffic children were found to be significantly higher in summer period (mean ± SD, 2.68 ± 1.99) when compared to winter period (1.64 ± 1.59; p = 0.004). On the other hand, no seasonality was observed for the suburban children. Similar results have been obtained in the BEC frequency with MN in our study. In summer, BEC-MN frequencies were significantly increased with the decrease in pulmonary function levels based on forced expiratory flow between 25 and 75% of vital capacity (FEF25-75%) levels (p < 0.05). As a conclusion, children living in urban-traffic and suburban areas in the city of Eskişehir exhibited similar genotoxicity. Seasonal variation in genotoxicity may be interpreted as relatively high ozone levels and increasing time spent at outdoors in the summer.
Rohmann, Kevin N.; Bass, Andrew H.
2011-01-01
SUMMARY Vertebrates displaying seasonal shifts in reproductive behavior provide the opportunity to investigate bidirectional plasticity in sensory function. The midshipman teleost fish exhibits steroid-dependent plasticity in frequency encoding by eighth nerve auditory afferents. In this study, evoked potentials were recorded in vivo from the saccule, the main auditory division of the inner ear of most teleosts, to test the hypothesis that males and females exhibit seasonal changes in hair cell physiology in relation to seasonal changes in plasma levels of steroids. Thresholds across the predominant frequency range of natural vocalizations were significantly less in both sexes in reproductive compared with non-reproductive conditions, with differences greatest at frequencies corresponding to call upper harmonics. A subset of non-reproductive males exhibiting an intermediate saccular phenotype had elevated testosterone levels, supporting the hypothesis that rising steroid levels induce non-reproductive to reproductive transitions in saccular physiology. We propose that elevated levels of steroids act via long-term (days to weeks) signaling pathways to upregulate ion channel expression generating higher resonant frequencies characteristic of non-mammalian auditory hair cells, thereby lowering acoustic thresholds. PMID:21562181
Avionics electromagnetic interference immunity and environment
NASA Technical Reports Server (NTRS)
Clarke, C. A.
1986-01-01
Aircraft electromagnetic spectrum and radio frequency (RF) field strengths are charted, profiling the higher levels of electromagnetic voltages encountered by the commercial aircraft wiring. Selected military, urban, and rural electromagnetic field levels are plotted and provide a comparison of radiation amplitudes. Low frequency magnetic fields and electric fields from 400 H(Z) power systems are charted versus frequency and wire separation to indicate induced voltages on adjacent or neighboring circuits. Induced EMI levels and attenuation characteristics of electric, magnetic, RF fields, and transients are plotted and graphed for common types of wire circuits. The significance of wire circuit returns and shielding is emphasized to highlight the techniques that help block the paths of electromagnetic interference and maintain avionic interface signal quality.
Salicylate-induced changes in auditory thresholds of adolescent and adult rats.
Brennan, J F; Brown, C A; Jastreboff, P J
1996-01-01
Shifts in auditory intensity thresholds after salicylate administration were examined in postweanling and adult pigmented rats at frequencies ranging from 1 to 35 kHz. A total of 132 subjects from both age levels were tested under two-way active avoidance or one-way active avoidance paradigms. Estimated thresholds were inferred from behavioral responses to presentations of descending and ascending series of intensities for each test frequency value. Reliable threshold estimates were found under both avoidance conditioning methods, and compared to controls, subjects at both age levels showed threshold shifts at selective higher frequency values after salicylate injection, and the extent of shifts was related to salicylate dose level.
Lahav, Amir
2015-01-01
Recent research raises concerns about the adverse effects of noise exposure on the developing preterm infant. However, current guidelines for NICU noise remain focused on loudness levels, leaving the problem of exposure to potentially harmful sound frequencies largely overlooked. This study examined the frequency spectra present in a level-II NICU. Noise measurements were taken in two level-II open-bay nurseries. Measurements were taken over 5 days for a period of 24 h each. Spectral analysis was focused on comparing sound frequencies in the range of human speech during daytime (7 AM-7 PM) vs. night-time (7 PM-7 AM). On average, daytime noise levels (Leq = 60.05 dBA) were higher than night-time (Leq = 58.67 dBA). Spectral analysis of frequency bands (>50 dB) revealed that infants were exposed to frequencies <500 Hz 100% of the time and to frequencies >500 Hz 57% of the time. During daytime, infants were exposed to nearly 20% more sounds within the speech frequency range compared with night-time (p = 0.018). Measuring the frequency spectra of NICU sounds is necessary to attain a thorough understanding of both the noise levels and the type of sounds that preterm infants are exposed to throughout their hospital stay. The risk of high-frequency noise exposure in the preterm population is still unclear and warrants further investigation. © 2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.
Derryberry, Elizabeth P; Gentry, Katherine; Derryberry, Graham E; Phillips, Jennifer N; Danner, Raymond M; Danner, Julie E; Luther, David A
2017-07-01
The soundscape acts as a selective agent on organisms that use acoustic signals to communicate. A number of studies document variation in structure, amplitude, or timing of signal production in correspondence with environmental noise levels thus supporting the hypothesis that organisms are changing their signaling behaviors to avoid masking. The time scale at which organisms respond is of particular interest. Signal structure may evolve across generations through processes such as cultural or genetic transmission. Individuals may also change their behavior during development (ontogenetic change) or in real time (i.e., immediate flexibility). These are not mutually exclusive mechanisms, and all must be investigated to understand how organisms respond to selection pressures from the soundscape. Previous work on white-crowned sparrows ( Zonotrichia leucophrys ) found that males holding territories in louder areas tend to sing higher frequency songs and that both noise levels and song frequency have increased over time (30 years) in urban areas. These previous findings suggest that songs are changing across generations; however, it is not known if this species also exhibits immediate flexibility. Here, we conducted an exploratory, observational study to ask whether males change the minimum frequency of their song in response to immediate changes in noise levels. We also ask whether males sing louder, as increased minimum frequency may be physiologically linked to producing sound at higher amplitudes, in response to immediate changes in environmental noise. We found that territorial males adjust song amplitude but not minimum frequency in response to changes in environmental noise levels. Our results suggest that males do not show immediate flexibility in song minimum frequency, although experimental manipulations are needed to test this hypothesis further. Our work highlights the need to investigate multiple mechanisms of adaptive response to soundscapes.
Bright, Charlotte Lyn; Jun, Hyun-Jin; Stapleton, Laura M.
2015-01-01
Throughout adolescence, alcohol consumption and aggressive behaviors are associated with multiple problematic outcomes. Few studies have examined neighborhood-level predictors and individual and family-level sociodemographic variables to describe longitudinal trajectories of these problem behaviors. Therefore, this study investigated the unique contributions of neighborhood and sociodemographic factors in the shared development of aggressive behaviors and drinking in adolescents. We analyzed alcohol consumption frequency and frequency of aggressive behaviors using parallel process latent growth curve models with demographic indicators and neighborhood constructs as predictors. At all ages, alcohol use and aggression positively covaried. Male gender was associated with both aggressive episodes and alcohol use at age 12. African American ethnicity was associated with higher levels of early aggression. Higher neighborhood income was associated with lower levels of early aggression. Findings lend support to current efforts to curb early initiation of alcohol use and aggression. PMID:26413037
Common FABP4 genetic variants and plasma levels of fatty acid binding protein 4 in older adults.
Mukamal, Kenneth J; Wilk, Jemma B; Biggs, Mary L; Jensen, Majken K; Ix, Joachim H; Kizer, Jorge R; Tracy, Russell P; Zieman, Susan J; Mozaffarian, Dariush; Psaty, Bruce M; Siscovick, David S; Djoussé, Luc
2013-11-01
We examined common variants in the fatty acid binding protein 4 gene (FABP4) and plasma levels of FABP4 in adults aged 65 and older from the Cardiovascular Health Study. We genotyped rs16909187, rs1054135, rs16909192, rs10808846, rs7018409, rs2290201, and rs6992708 and measured circulating FABP4 levels among 3190 European Americans and 660 African Americans. Among European Americans, the minor alleles of six single nucleotide polymorphisms (SNP) were associated with lower FABP4 levels (all p ≤ 0.01). Among African Americans, the SNP with the lowest minor allele frequency was associated with lower FABP4 levels (p = 0.015). The C-A haplotype of rs16909192 and rs2290201 was associated with lower FABP4 levels in both European Americans (frequency = 16 %; p = 0.001) and African Americans (frequency = 8 %; p = 0.04). The haplotype combined a SNP in the first intron with one in the 3'untranslated region. However, the alleles associated with lower FABP4 levels were associated with higher fasting glucose in meta-analyses from the MAGIC consortium. These results demonstrate associations of common SNP and haplotypes in the FABP4 gene with lower plasma FABP4 but higher fasting glucose levels.
Micronucleus frequency in Danish schoolchildren and their mothers from the DEMOCOPHES population.
Mørck, Thit A; Loock, Kim Vande; Poulsen, Maria Bech; Siersma, Volkert D; Nielsen, Jeanette K S; Hertel, Ole; Kirsch-Volders, Micheline; Knudsen, Lisbeth E
2016-01-01
Micronucleus (MN) frequency is a biomarker for early genetic effects which is often used in human biomonitoring studies. Increased frequency of micronuclei has been associated with high levels of traffic exposure. Further high MN frequency was found predictive for cancer development in several studies of adults. In the present study, the MN frequency in blood samples from the Danish participants of the European pilot project DEMOCOPHES was analysed and related to the area of residence, self-reported and calculated exposure to road traffic as well as to mercury in hair and blood concentrations of persistent organic pollutants and dioxin-like activity measured in the same participants. The MN frequency analysis was performed with the cytokinesis-block micronucleus (CBMN) assay and included 100 children and 119 mothers. We found a significant correlation between mothers and children in the levels of micronuclei in 1000 binucleated T lymphocytes (‰MNBN) and in the proliferation index. Further the levels of ‰MNBN were significantly higher in mothers compared with their children. No significant associations were found for ‰MNBN for traffic related exposure in neither children nor their mothers. In children, a 2.5 times higher micronuclei in mononuclear T lymphocytes were found in children living within 50 m of a busy road, however, this was not found in mothers or in MNBN and the effect of exposure to road traffic on MN frequency needs further investigation. No significant associations were found between MN frequencies and the other biomarkers measured in the same participants. © The Author 2015. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
[Effects of extremely low frequency electromagnetic radiation on cardiovascular system of workers].
Zhao, Long-yu; Song, Chun-xiao; Yu, Duo; Liu, Xiao-liang; Guo, Jian-qiu; Wang, Chuan; Ding, Yuan-wei; Zhou, Hong-xia; Ma, Shu-mei; Liu, Xiao-dong; Liu, Xin
2012-03-01
To observe the exposure levels of extremely low frequency electromagnetic fields in workplaces and to analyze the effects of extremely low frequency electromagnetic radiation on cardiovascular system of occupationally exposed people. Intensity of electromagnetic fields in two workplaces (control and exposure groups) was detected with EFA-300 frequency electromagnetic field strength tester, and intensity of the noise was detected with AWA5610D integral sound level. The information of health physical indicators of 188 controls and 642 occupationally exposed workers was collected. Data were analyzed by SPSS17.0 statistic software. The intensity of electric fields and the magnetic fields in exposure groups was significantly higher than that in control group (P < 0.05), but there was no significant difference of noise between two workplaces (P > 0.05). The results of physical examination showed that the abnormal rates of HCY, ALT, AST, GGT, ECG in the exposure group were significantly higher than those in control group (P < 0.05). There were no differences of sex, age, height, weight between two groups (P > 0.05). Exposure to extremely low frequency electromagnetic radiation may have some effects on the cardiovascular system of workers.
Between-country comparison of whole-body SAR from personal exposure data in Urban areas.
Joseph, Wout; Frei, Patrizia; Röösli, Martin; Vermeeren, Günter; Bolte, John; Thuróczy, György; Gajšek, Peter; Trček, Tomaž; Mohler, Evelyn; Juhász, Péter; Finta, Viktoria; Martens, Luc
2012-12-01
In five countries (Belgium, Switzerland, Slovenia, Hungary, and the Netherlands), personal radio frequency electromagnetic field measurements were performed in different microenvironments such as homes, public transports, or outdoors using the same exposure meters. From the mean personal field exposure levels (excluding mobile phone exposure), whole-body absorption values in a 1-year-old child and adult male model were calculated using a statistical multipath exposure method and compared for the five countries. All mean absorptions (maximal total absorption of 3.4 µW/kg for the child and 1.8 µW/kg for the adult) were well below the International Commission on Non-Ionizing Radiation Protection (ICNIRP) basic restriction of 0.08 W/kg for the general public. Generally, incident field exposure levels were well correlated with whole-body absorptions (SAR(wb) ), although the type of microenvironment, frequency of the signals, and dimensions of the considered phantom modify the relationship between these exposure measures. Exposure to the television and Digital Audio Broadcasting band caused relatively higher SAR(wb) values (up to 65%) for the 1-year-old child than signals at higher frequencies due to the body size-dependent absorption rates. Frequency Modulation (FM) caused relatively higher absorptions (up to 80%) in the adult male. Copyright © 2012 Wiley Periodicals, Inc.
Clegg, Isabella L K; Delfour, Fabienne
2018-03-01
Many animals display a suite of increased vigilance and/or activity responses in relation to upcoming events, termed "anticipatory behavior." Anticipatory behavior toward positive events has been suggested as a cross-species measure of affective state as it likely reflects the balance of the reward-sensitivity system: various studies suggest that animals in poorer welfare situations show higher or excessive levels of anticipation for positive events. Another tool for evaluating animals' affective state is cognitive bias testing, and although it has been attempted, a link has not yet been made between cognitive bias and anticipatory behavior levels. Bottlenose dolphins (Tursiops truncatus) in captivity increase the performance of behaviors such as surface-looking and spy-hopping in anticipation of training sessions during which food is provided. In this study we measured anticipatory behavior frequency in bottlenose dolphins prior to positive reinforcement training sessions, and assessed whether frequency of anticipatory behavior correlated with their performance on cognitive bias tasks. We found that higher frequencies of anticipatory behavior for training sessions was significantly associated with more pessimistic judgements in cognitive bias tests, supporting previous findings linking higher reward sensitivity with negative affective states. Anticipatory behavior is an easily measured activity and could represent a welfare indicator in dolphins as well as other animals in captive environments. © 2018 Wiley Periodicals, Inc.
Unlocking higher harmonics in atomic force microscopy with gentle interactions.
Santos, Sergio; Barcons, Victor; Font, Josep; Verdaguer, Albert
2014-01-01
In dynamic atomic force microscopy, nanoscale properties are encoded in the higher harmonics. Nevertheless, when gentle interactions and minimal invasiveness are required, these harmonics are typically undetectable. Here, we propose to externally drive an arbitrary number of exact higher harmonics above the noise level. In this way, multiple contrast channels that are sensitive to compositional variations are made accessible. Numerical integration of the equation of motion shows that the external introduction of exact harmonic frequencies does not compromise the fundamental frequency. Thermal fluctuations are also considered within the detection bandwidth of interest and discussed in terms of higher-harmonic phase contrast in the presence and absence of an external excitation of higher harmonics. Higher harmonic phase shifts further provide the means to directly decouple the true topography from that induced by compositional heterogeneity.
Hareuveny, Ronen; Sudan, Madhuri; Halgamuge, Malka N.; Yaffe, Yoav; Tzabari, Yuval; Namir, Daniel; Kheifets, Leeka
2015-01-01
This study characterizes extremely low frequency (ELF) magnetic field (MF) levels in 10 car models. Extensive measurements were conducted in three diesel, four gasoline, and three hybrid cars, under similar controlled conditions and negligible background fields. Averaged over all four seats under various driving scenarios the fields were lowest in diesel cars (0.02 μT), higher for gasoline (0.04–0.05 μT) and highest in hybrids (0.06–0.09 μT), but all were in-line with daily exposures from other sources. Hybrid cars had the highest mean and 95th percentile MF levels, and an especially large percentage of measurements above 0.2 μT. These parameters were also higher for moving conditions compared to standing while idling or revving at 2500 RPM and higher still at 80 km/h compared to 40 km/h. Fields in non-hybrid cars were higher at the front seats, while in hybrid cars they were higher at the back seats, particularly the back right seat where 16%–69% of measurements were greater than 0.2 μT. As our results do not include low frequency fields (below 30 Hz) that might be generated by tire rotation, we suggest that net currents flowing through the cars’ metallic chassis may be a possible source of MF. Larger surveys in standardized and well-described settings should be conducted with different types of vehicles and with spectral analysis of fields including lower frequencies due to magnetization of tires. PMID:25647323
Primary Sjögren Syndrome in Han Chinese
Zhao, Yun; Li, Ya; Wang, Li; Li, Xiao-Feng; Huang, Ci-Bo; Wang, Guo-Chun; Zhang, Xue-Wu; Zhang, Zhuo-Li; Zhang, Xiao; Xiao, Wei-Guo; Dai, Lie; Wang, Yong-Fu; Hu, Shao-Xian; Li, Hong-Bin; Gong, Lu; Liu, Bin; Sun, Ling-Yun; Zhang, Miao-Jia; Zhang, Xuan; Li, Yong-Zhe; Du, De-Shun; Zhang, Shun-Hua; Sun, Yuan-Yuan; Zhang, Feng-Chun
2015-01-01
Abstract The epidemiological characteristics of Sjögren syndrome (SS) are significantly varied in different countries. We conducted the present study to survey the epidemiological characteristics of primary SS in China. We recruited 483 primary SS patients from 16 Chinese medical centers nationwide from January 2009 to November 2011 and assessed salivary and lacrimal gland dysfunction, organ involvement, and autoimmunity in these patients. The cohort included 456 women and 27 men (ratio, 17:1; mean age at onset, 42 ± 11 years; median age at diagnosis, 49 years; range, 41–56 years). Male patients showed a lower frequency of xerophthalmia (37.0% vs 60.7%) and a higher frequency of arthritis (40.7% vs 16.4%). Young-onset patients showed a higher frequency of low C3 levels (57.7% vs 36.3%) and pancytopenia (22.2% vs 8.8%). Patients with systemic involvement had a higher frequency of immunoglobulin A (IgA) (39.4% vs 22.5%) and immunoglobulin M (IgM) (12.4% vs 37.9%). Patients with pulmonary involvement had a higher parotid enlargement (21.4% vs 10.2%), purpura (12.1% vs 5.7%) and higher anti-La/SS-B (61.7% vs 41.8%), immunoglobulin G (IgG) (80.7% vs 64.6%) and IgA (48.9% vs 30.6%) levels. Patients with anti-Ro/SSA antibodies had more frequent exocrine gland symptoms and some extraglandular symptoms and immunological alterations. Compared with previous studies performed in other countries, SS patients in China showed particular clinical manifestation, systemic involvement, and immunological alterations. PMID:25906094
Rendina, H Jonathon; Moody, Raymond L; Ventuneac, Ana; Grov, Christian; Parsons, Jeffrey T
2015-09-01
Despite limited research, some evidence suggests that examining substance use at multiple levels may be of greater utility in predicting sexual behavior than utilizing one level of measurement, particularly when investigating different substances simultaneously. We aimed to examine aggregate and event-level associations between three forms of substance use - alcohol, marijuana, and club drugs - and two sexual behavior outcomes - sexual engagement and condomless anal sex (CAS). Analyses focused on both 6-week timeline follow-back (TLFB; retrospective) and 30-day daily diary (prospective) data among a demographically diverse sample of 371 highly sexually active HIV-positive and HIV-negative gay and bisexual men. Models from both TLFB and diary showed that event-level use of alcohol, marijuana, and club drugs was associated with increased sexual engagement, while higher aggregated frequency marijuana and any frequency club drug use were associated with decreased sexual engagement. Event-level use of club drugs was consistently associated with increased odds of CAS across both TLFB and diary models while higher frequency marijuana use was most consistently associated with a lower odds of CAS. Findings indicated that results are largely consistent between retrospective and prospective data, but that retrospective results for substance use and sexual engagement were generally greater in magnitude. These results suggest that substance use primarily acts to increase sexual risk at the event-level and less so through individual-level frequency of use; moreover, it primarily does so by increasing the likelihood of sex on a given day with fewer significant associations with the odds of CAS on sex days. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Rendina, H. Jonathon; Moody, Raymond L.; Ventuneac, Ana; Grov, Christian; Parsons, Jeffrey T.
2015-01-01
Background Despite limited research, some evidence suggests that examining substance use at multiple levels may be of greater utility in predicting sexual behavior than utilizing one level of measurement, particularly when investigating different substances simultaneously. We aimed to examine aggregated and event-level associations between three forms of substance use—alcohol, marijuana, and club drugs—and two sexual behavior outcomes—sexual engagement and condomless anal sex (CAS). Method Analyses focused on both 6-week timeline follow-back (TLFB; retrospective) and 30-day daily diary (prospective) data among a demographically diverse sample of 371 highly sexually active HIV-positive and HIV-negative gay and bisexual men. Results Models from both TLFB and diary showed that event-level use of alcohol, marijuana, and club drugs was associated with increased sexual engagement, while higher aggregated frequency marijuana and any frequency club drug use were associated with decreased sexual engagement. Event-level use of club drugs was consistently associated with increased odds of CAS across both TLFB and diary models while higher frequency marijuana use was most consistently associated with a lower odds of CAS. Conclusions Findings indicated that results are largely consistent between retrospective and prospective data, but that retrospective results for substance use and sexual engagement were generally greater in magnitude. These results suggest that substance use primarily acts to increase sexual risk at the event-level and less so through individual-level frequency of use; moreover, it primarily does so by increasing the likelihood of sex on a given day with fewer significant associations with the odds of CAS on sex days. PMID:26190557
Lutfi, Mohamed Faisal
2017-01-01
Anxiety and cardiac autonomic modulations (CAM) were thoroughly investigated in coronary artery disease (CAD) and cardiac syndrome X (CSX) patients worldwide, but not among Sudanese with similar pathology. To compare levels of anxiety and CAM between Sudanese patients with CSX and CAD. Anxiety was evaluated in 51 CAD and 26 CSX patients using Taylor Manifest anxiety score (TMAS) questionnaire while heart rate variability derived indices were used to assess CAM, namely natural logarithm of low frequency (LnLF), high frequency (LnHF) and LF/HF ratio (LnLF/HF). Low anxiety levels were achieved by 6 (23.1%) and 9 (17.6%) patients with CSX and CAD respectively. High anxiety level was achieved by only one (3.8%) patient, who was suffering from CSX. TMAS was significantly higher in CSX (31.27 (21.97)) compared to CAD (21.86 (12.97), P = 0.021). However, abnormally increased anxiety was not associated with higher risk of CSX. LnLF, LnHF and LnLF/HF were comparable in CAD and CSX patients. CSX and CAD patients showed comparable CAM. Although anxiety levels were higher in CSX compared to CAD, TMAS ≥ 35 failed to show significant association with CSX.
Multimode Directional Coupler for Utilization of Harmonic Frequencies from TWTAs
NASA Technical Reports Server (NTRS)
Simmons, Rainee N.; Wintucky, Edwin G.
2013-01-01
A novel waveguide multimode directional coupler (MDC) intended for the measurement and potential utilization of the second and higher order harmonic frequencies from high-power traveling wave tube amplifiers (TWTAs) has been successfully designed, fabricated, and tested. The design is based on the characteristic multiple propagation modes of the electrical and magnetic field components of electromagnetic waves in a rectangular waveguide. The purpose was to create a rugged, easily constructed, more efficient waveguide- based MDC for extraction and exploitation of the second harmonic signal from the RF output of high-power TWTs used for space communications. The application would be a satellitebased beacon source needed for Qband and V/W-band atmospheric propagation studies. The MDC could function as a CW narrow-band source or as a wideband source for study of atmospheric group delay effects on highdata- rate links. The MDC is fabricated from two sections of waveguide - a primary one for the fundamental frequency and a secondary waveguide for the second harmonic - that are joined together such that the second harmonic higher order modes are selectively coupled via precision- machined slots for propagation in the secondary waveguide. In the TWTA output waveguide port, both the fundamental and the second harmonic signals are present. These signals propagate in the output waveguide as the dominant and higher order modes, respectively. By including an appropriate mode selective waveguide directional coupler, such as the MDC presented here at the output of the TWTA, the power at the second harmonic can be sampled and amplified to the power level needed for atmospheric propagation studies. The important conclusions from the preliminary test results for the multimode directional coupler are: (1) the second harmonic (Ka-band) can be measured and effectively separated from the fundamental (Ku-band) with no coupling of the latter, (2) power losses in the fundamental frequency are negligible, and (3) the power level of the extracted second harmonic is sufficient for further amplification to power levels needed for practical applications. It was also demonstrated that third order and potentially higher order harmonics are measurable with this device. The design is frequency agnostic, and with the appropriate choice of waveguides, is easily scaled to higher frequency TWTs. The MDC has the same function but with a number of important advantages over the conventional diplexer.
Jarvie, Jennifer L; Whooley, Mary A; Regan, Mathilda C; Sin, Nancy L; Cohen, Beth E
2014-10-15
Higher levels of physical activity are associated with lower rates of coronary heart disease (CHD). Previous studies have suggested that this is due partly to lower levels of inflammation and insulin resistance. The aim of this study was to determine whether physical activity level was associated with inflammation or insulin resistance during a 5-year period in outpatients with known CHD. A total of 656 participants from the Heart and Soul Study, a prospective cohort study of outpatients with documented CHD, were evaluated. Self-reported physical activity frequency was assessed at baseline and after 5 years of follow-up. Participants were classified as low versus high activity at each visit, yielding 4 physical activity groups: stable low activity, decreasing activity (high at baseline to low at year 5), increasing activity (low at baseline to high at year 5), and stable high activity. Year 5 markers of inflammation (C-reactive protein [CRP], interleukin-6, and fibrinogen) and insulin resistance (insulin, glucose, and glycated hemoglobin) were compared across the 4 activity groups. After 5 years of follow-up, higher activity was associated with lower mean levels of all biomarkers. In the fully adjusted regression models, CRP, interleukin-6, and glucose remained independently associated with physical activity frequency (log CRP, p for trend across activity groups = 0.03; log interleukin-6, p for trend = 0.01; log glucose, p for trend = 0.003). Subjects with stable high activity typically had the lowest levels of biomarkers. In conclusion, in this novel population of outpatients with known CHD followed for 5 years, higher physical activity frequency was independently associated with lower levels of CRP, interleukin-6, and glucose. Copyright © 2014 Elsevier Inc. All rights reserved.
Kuribayashi, Ryuma; Nittono, Hiroshi
2017-01-01
High-resolution audio has a higher sampling frequency and a greater bit depth than conventional low-resolution audio such as compact disks. The higher sampling frequency enables inaudible sound components (above 20 kHz) that are cut off in low-resolution audio to be reproduced. Previous studies of high-resolution audio have mainly focused on the effect of such high-frequency components. It is known that alpha-band power in a human electroencephalogram (EEG) is larger when the inaudible high-frequency components are present than when they are absent. Traditionally, alpha-band EEG activity has been associated with arousal level. However, no previous studies have explored whether sound sources with high-frequency components affect the arousal level of listeners. The present study examined this possibility by having 22 participants listen to two types of a 400-s musical excerpt of French Suite No. 5 by J. S. Bach (on cembalo, 24-bit quantization, 192 kHz A/D sampling), with or without inaudible high-frequency components, while performing a visual vigilance task. High-alpha (10.5-13 Hz) and low-beta (13-20 Hz) EEG powers were larger for the excerpt with high-frequency components than for the excerpt without them. Reaction times and error rates did not change during the task and were not different between the excerpts. The amplitude of the P3 component elicited by target stimuli in the vigilance task increased in the second half of the listening period for the excerpt with high-frequency components, whereas no such P3 amplitude change was observed for the other excerpt without them. The participants did not distinguish between these excerpts in terms of sound quality. Only a subjective rating of inactive pleasantness after listening was higher for the excerpt with high-frequency components than for the other excerpt. The present study shows that high-resolution audio that retains high-frequency components has an advantage over similar and indistinguishable digital sound sources in which such components are artificially cut off, suggesting that high-resolution audio with inaudible high-frequency components induces a relaxed attentional state without conscious awareness.
Effects of forward motion on jet and core noise
NASA Technical Reports Server (NTRS)
Low, J. K. C.
1977-01-01
A study was conducted to investigate the effects of forward motion on both jet and core noise. Measured low-frequency noise from static-engine and from flyover tests with a DC-9-30 powered by JT8D-109 turbofan engines and with a DC-10-40 powered by JT9D-59A turbofan engines was separated into jet- and core noise components. Comparisons of the static and the corresponding in-flight jet- and core-noise components are presented. The results indicate that for the DC-9 airplane at low power settings, where core noise is predominant, the effect of convective amplification on core-noise levels is responsible for the higher in-flight low-frequency noise levels in the inlet quadrant. Similarly, it was found that for the DC-10 airplane with engines mounted under the wings and flaps and flap deflection greater than 30 degrees, the contribution from jet-flap-interaction noise is as much as 5 dB in the inlet quadrant and is responsible for higher in-flight low-frequency noise levels during approach conditions. Those results indicate that to properly investigate flight effects, it is important to consider the noise contributions from other low-frequency sources, such as the core and the jet-flap interaction.
NASA Astrophysics Data System (ADS)
Schwalm, Afton Leigh
California sea lions (Zalophus californianus) are a highly popular and easily recognized marine mammal in zoos, aquariums, circuses, and often seen by ocean visitors. They are highly vocal and gregarious on land. Surprisingly, little research has been performed on the vocalization types, source levels, acoustic properties, and functions of airborne sounds used by California sea lions. This research on airborne vocalizations of California sea lions will advance the understanding of this aspect of California sea lions communication, as well as examine the relationship between health condition and acoustic behavior. Using a PhillipsRTM digital recorder with attached microphone and a calibrated RadioShackRTM sound pressure level meter, acoustical data were recorded opportunistically on California sea lions during rehabilitation at The Marine Mammal Center in Sausalito, CA. Vocalizations were analyzed using frequency, time, and amplitude variables with Raven Pro: Interactive Sound Analysis Software Version 1.4 (The Cornell Lab of Ornithology, Ithaca, NY). Five frequency, three time, and four amplitude variables were analyzed for each vocalization. Differences in frequency, time, and amplitude variables were not significant by sex. The older California sea lion group produced vocalizations that were significantly lower in four frequency variables, significantly longer in two time variables, significantly higher in calibrated maximum and minimum amplitude variables, and significantly lower in frequency at maximum and minimum amplitude compared with pups. Six call types were identified: bark, goat, growl/grumble, bark/grumble, bark/growl, and grumble/moan. The growl/grumble call was higher in dominant beginning, ending, and minimum frequency, as well as in the frequency at maximum amplitude compared with the bark, goat, bark/grumble calls in the first versus last vocalization sample. The goat call was significantly higher in first harmonic interval than any other call type in the all vocalizations sample. The "fate" of a sea lion was categorized as: released, placed at another facility, remained at TMMC, euthanized, or died. To determine if acoustic features could be used to assess the recovery of a pup, the acoustic features of a pup's first recorded vocalization were compared with the frequency, time, and amplitude of the last vocalization recorded (i.e., before it was released or placed at another facility). In addition, all first vocalizations were pooled and all last vocalizations were pooled for acoustic analysis, regardless of their fate. Released pups had shorter duration calls, a greater first harmonic interval, and a higher dominant maximum frequency than either pups that died or pups remaining at TMMC. Released pups had a higher frequency at maximum and minimum amplitude compared to dead and remaining pups. Pups that died had significantly lower dominant ending frequency and a lower dominant minimum frequency than released or remaining pups. These results were supported by other studies on different species of otariids, phocids, and cetaceans. The preliminary analyses presented in this thesis holds promise that with additional data acoustic features of California sea lion airborne vocalizations could indicate sex, age, and possibly health condition or the potential for release.
Reducing microwave absorption with fast frequency modulation.
Qin, Juehang; Hubler, A
2017-05-01
We study the response of a two-level quantum system to a chirp signal, using both numerical and analytical methods. The numerical method is based on numerical solutions of the Schrödinger solution of the two-level system, while the analytical method is based on an approximate solution of the same equations. We find that when two-level systems are perturbed by a chirp signal, the peak population of the initially unpopulated state exhibits a high sensitivity to frequency modulation rate. We also find that the aforementioned sensitivity depends on the strength of the forcing, and weaker forcings result in a higher sensitivity, where the frequency modulation rate required to produce the same reduction in peak population would be lower. We discuss potential applications of this result in the field of microwave power transmission, as it shows applying fast frequency modulation to transmitted microwaves used for power transmission could decrease unintended absorption of microwaves by organic tissue.
NASA Astrophysics Data System (ADS)
Vergne, Jerome; Blachet, Antoine; Lehujeur, Maximilien
2015-04-01
Monitoring local or regional seismic activity requires stations having a low level of background seismic noise at frequencies higher than few tenths of Hertz. Network operators are well aware that the seismic quality of a site depends on several aspects, among them its geological setting and the proximity of roads, railways, industries or trees. Often, the impact of each noise source is only qualitatively known which precludes estimating the quality of potential future sites before they are tested or installed. Here, we want to take advantage of a very dense temporary network deployed in Northern Alsace (France) to assess the effect of various kinds of potential sources on the level of seismic noise observed in the frequency range 0.2-50 Hz. In September 2014, more than 250 seismic stations (FairfieldNodal@ Zland nodes with 10Hz vertical geophone) have been installed every 1.5 km over a ~25km diameter disc centred on the deep geothermal sites of Soultz-sous-Forêts and Rittershoffen. This region exhibits variable degrees of human imprints from quite remote areas to sectors with high traffic roads and big villages. It also encompasses both the deep sedimentary basin of the Rhine graben and the piedmont of the Vosges massif with exposed bedrock. For each site we processed the continuous data to estimate probability density functions of the power spectral densities. At frequencies higher than 1 Hz most sites show a clear temporal modulation of seismic noise related to human activity with the well-known variations between day and night and between weekdays and weekends. Moreover we observe a clear evolution of the spatial distribution of seismic noise levels with frequency. Basically, between 0.5 and 4 Hz the geological setting modulates the level of seismic noise. At higher frequencies, the amplitude of seismic noise appears mostly related to the distance to nearby roads. Based on road maps and traffic estimation, a forward approach is performed to model the induced seismic noise. Effects of other types of seismic sources, such as industries or wind, are also observed but usually have a more limited spatial extension and a specific signature in the spectrograms.
Becker, Sara J; Kelly, Lourah M; Kang, Augustine W; Escobar, Katherine I; Squires, Daniel D
2018-03-29
Contingency management (CM) is an evidence-based behavioral intervention for opioid use disorders (OUDs); however, CM adoption in OUD treatment centers remains low due to barriers at patient, provider, and organizational levels. In a recent trial, OUD treatment providers who received the Science to Service Laboratory (SSL), a multilevel implementation strategy developed by a federally funded addiction training center, had significantly greater odds of CM adoption than providers who received training as usual. This study examined whether CM adoption frequency varied as a function of provider sociodemographic characteristics (i.e., age, race/ethnicity, licensure) and perceived barriers to adoption (i.e., patient-, provider-, organization-level) among providers receiving the SSL in an opioid treatment program. Thirty-nine providers (67% female, 77% non-Hispanic white, 72% with specialty licensure, M age = 42 [SD = 11.46]) received the SSL, which consisted of didactic training, performance feedback, specialized training of internal change champions, and external coaching. Providers completed a comprehensive baseline assessment and reported on their adoption of CM biweekly for 52 weeks. Providers reported using CM an average of nine 2-week intervals (SD = 6.35). Hierarchical multiple regression found that providers identifying as younger, non-Hispanic white, and without addiction-related licensure all had higher levels of CM adoption frequency. Higher perceived patient-level barriers predicted lower levels of CM adoption frequency, whereas provider- and organization-level barriers were not significant predictors. The significant effect of age on CM adoption frequency was consistent with prior research on predictors of evidence-based practice adoption, whereas the effect of licensure was counter to prior research. The finding that CM adoption frequency was lower among racially/ethnically diverse providers was not expected and suggests that the SSL may require adaptation to meet the needs of diverse opioid treatment providers. Entities using the SSL may also wish to incorporate a more explicit focus on patient-level barriers.
Possible Explanation for Cancer in Rats due to Cell Phone Radio Frequency Radiation
NASA Astrophysics Data System (ADS)
Feldman, Bernard J.
Very recently, the National Toxicology Program reported a correlation between exposure to whole body 900 MHz radio frequency radiation and cancer in the brains and hearts of Sprague Dawley male rats. Assuming that the National Toxicology Program is statistically significant, I propose the following explanation for these results. The neurons around the brain and heart form closed electrical circuits and, following Faraday's Law, 900 MHz radio frequency radiation induces 900 MHz electrical currents in these neural circuits. In turn, these 900 MHz currents in the neural circuits generate sufficient localized heat in the neural cells to shift the equilibrium concentration of carcinogenic radicals to higher levels and thus, to higher incidences of cancer.
Tennakoon, Sampath U B; Kumar, Bernadette N; Meyer, Haakon E
2015-03-01
Sri Lankans in Oslo have previously been shown to have lower risk of cardiovascular disease compared with those in Kandy, Sri Lanka. Here we present lifestyle risk factors for cardiovascular diseases: frequency and type of fat consumed, frequency of fruit and vegetable intake, alcohol consumption, and leisure time physical activity between 1145 Sri Lankans living in Oslo and 678 Tamils and Sinhalese Sri Lankans living in Kandy as possible explanatory factors for the differences observed. Those in Oslo were consuming healthier fats and reported higher levels of physical activity but frequency of vegetable and fruit consumption was lower. Alcohol consumption among women was negligible. Type of fats consumed might be protective for Oslo group compared with predominantly saturated fat diet in Kandy. Higher leisure time physical activity may also be protective for the Oslo group. Higher frequency of consumption of vegetables and fruits may be beneficial in Kandy. © 2013 APJPH.
Development of Turbulence-Measuring Equipment
NASA Technical Reports Server (NTRS)
Kovasznay, Leslie S G
1954-01-01
Hot wire turbulence-measuring equipment has been developed to meet the more stringent requirements involved in the measurement of fluctuations in flow parameters at supersonic velocities. The higher mean speed necessitates the resolution of higher frequency components than at low speed, and the relatively low turbulence level present at supersonic speed makes necessary an improved noise level for the equipment. The equipment covers the frequency range from 2 to about 70,000 cycles per second. Constant-current operation is employed. Compensation for hot-wire lag is adjusted manually using square-wave testing to indicate proper setting. These and other features make the equipment adaptable to all-purpose turbulence work with improved utility and accuracy over that of older types of equipment. Sample measurements are given to demonstrate the performance.
Hyperglycemia and adverse pregnancy outcome study: neonatal glycemia.
Metzger, Boyd E; Persson, Bengt; Lowe, Lynn P; Dyer, Alan R; Cruickshank, J Kennedy; Deerochanawong, Chaicharn; Halliday, Henry L; Hennis, Anselm J; Liley, Helen; Ng, Pak C; Coustan, Donald R; Hadden, David R; Hod, Moshe; Oats, Jeremy J N; Trimble, Elisabeth R
2010-12-01
The goal was to describe the temporal pattern of neonatal plasma glucose levels and associations with maternal glucose levels, cord serum C-peptide levels, and neonatal size and adiposity. A total of 17,094 mothers and infants were included in the Hyperglycemia and Adverse Pregnancy Outcome Study (15 centers in 9 countries). Mothers underwent a 75-g, 2-hour, oral glucose tolerance test (OGTT) at 24 to 32 weeks of gestation. Cord blood and neonatal blood samples were collected. Biochemical neonatal hypoglycemia was defined as glucose levels of <10th percentile (2.2 mmol/L). Clinically identified hypoglycemia was ascertained through medical record review and associations were assessed. Plasma glucose concentrations were stable during the first 5 hours after birth. Maternal glucose levels were weakly positively associated with biochemical neonatal hypoglycemia (odds ratios: 1.07-1.14 for 1-SD higher OGTT glucose levels). Frequency of neonatal hypoglycemia was higher with higher cord C-peptide levels (odds ratio: 11.6 for highest versus lowest C-peptide category). Larger and/or fatter infants were more likely to have hypoglycemia (P < .001), and infants with hypoglycemia tended to have a higher frequency of cord C-peptide levels of >90th percentile. Mean neonatal plasma glucose concentrations varied little in the first 5 hours after birth, which suggests normal postnatal adjustment. Biochemical and clinical hypoglycemia were weakly related to maternal OGTT glucose measurements but were strongly associated with elevated cord serum C-peptide levels. Larger and/or fatter infants were more likely to develop hypoglycemia and hyperinsulinemia. These relationships suggest physiologic relationships between maternal glycemia and fetal insulin production.
Bell, Wade E.; Hallworth, Richard; Wyatt, Todd A.; Sisson, Joseph H.
2015-01-01
When Paramecium encounters positive stimuli, the membrane hyperpolarizes and ciliary beat frequency increases. We adapted an established immobilization protocol using a biological adhesive and a novel digital analysis system to quantify beat frequency in immobilized Paramecium. Cells showed low mortality and demonstrated beat frequencies consistent with previous studies. Chemoattractant molecules, reduction in external potassium, and posterior stimulation all increased somatic beat frequency. In all cases, the oral groove cilia maintained a higher beat frequency than mid-body cilia, but only oral cilia from cells stimulated with chemoattactants showed an increase from basal levels. PMID:25066640
Watt-level single-frequency tunable neodymium MOPA fiber laser operating at 915-937 nm
NASA Astrophysics Data System (ADS)
Rota-Rodrigo, S.; Gouhier, B.; Laroche, M.; Zhao, J.; Canuel, B.; Bertoldi, A.; Bouyer, P.; Traynor, N.; Cadier, B.; Robin, T.; Santarelli, G.
2018-02-01
We have developed a Watt-level single-frequency tunable fiber laser in the 915-937 nm spectral window. The laser is based on a neodymium-doped fiber master oscillator power amplifier architecture, with two amplification stages using a 20 mW extended cavity diode laser as seed. The system output power is higher than 2 W from 921 to 933 nm, with a stability better than 1.4% and a low relative intensity noise.
Malta, Deborah Carvalho; Bernal, Regina Tomie Ivata; Lima, Margareth Guimarães; de Araújo, Silvânia Suely Caribé; da Silva, Marta Maria Alves; Freitas, Maria Imaculada de Fátima; Barros, Marilisa Berti de Azevedo
2017-01-01
ABSTRACT OBJECTIVE To assess whether sex, education level, and health insurance affect the use of health services among the adult Brazilian population with chronic noncommunicable diseases (NCD). METHODS Data from a cross-sectional survey were analyzed, the National Health Survey (PNS). Frequency of use of services in the population that referred at least one NCD were compared with the frequency from a population that did not report NCD, according to sex, education level, health insurance, and NCD number (1, 2, 3, 4, or more). The prevalence and prevalence ratios were calculated crude and adjusted for sex, age, region, and 95% confidence intervals. RESULTS The presence of a noncommunicable disease was associated with increase in hospitalizations in the last 12 months, in 1.7 times (95%CI 1.53–1.9). Failing to perform usual activities in the last two weeks for health reasons was 3.1 times higher in NCD carriers (95%CI 2.78–3.46); while the prevalence of medical consultation in the last 12 months was 1.26 times higher (95%CI 1.24–1.28). NCD carriers make more use of health services, as well as women, people with higher number of comorbidities, with health insurance, and higher education level. CONCLUSIONS NCD carriers make more use of health services, as well as women, people with higher number of comorbidities, with health insurance, and higher education level. PMID:28591353
Fang, Chenglong; Luo, Tingting; Lin, Ling
2017-12-01
We investigated whether serum CXC ligand 13 protein (CXCL13) levels correlate with the circulating plasmablasts and memory B-cells alteration in systemic lupus erythematosus (SLE) patients. The diagnostic use of CXCL13 concentrations in active lupus was also analyzed.A total of 36 SLE patients and 18 healthy controls were included. Serum CXCL13 levels were examined by enzyme-linked immunosorbent assay. The frequency and absolute count of circulating plasmablasts and memory B cells were analyzed by flow cytometry. Receiver operating characteristic curves (ROC curves) were generated to analyze the utility of serum CXCL13 level and plasmablasts frequency as tools for the recognition of active SLE.Elevation of serum CXCL13 levels, higher plasmablasts frequency, and reduction of memory B-cells count were observed in SLE patients, compared with healthy controls. Interestingly, correlational analyses showed not only significantly positive association between CXCL13 levels and SLE Disease Activity Index (SLEDAI) or plasmablasts frequency, but an inverse correlation between CXCL13 concentration and memory B-cell count. ROC curves showed that serum CXCL13 level and plasmablasts frequency were practical in identifying active disease from overall SLE patients, with considerable accuracy.Serum CXCL13 levels correlate with the alteration of plasmablasts and memory B cells in SLE. CXCL13 may be used as a practical tool in judgment of active SLE.
Bradley, Arthur; Xu, Renfeng; Thibos, Larry; Marin, Gildas; Hernandez, Martha
2014-01-01
Purpose To test competing hypotheses (Stiles Crawford pupil apodising or superior imaging of high spatial frequencies by the central pupil) for the pupil size independence of subjective refractions in the presence of primary spherical aberration. Methods Subjective refractions were obtained with a variety of test stimuli (high contrast letters, urban cityscape, high and low spatial frequency gratings) while modulating pupil diameter, levels of primary spherical aberration and pupil apodisation. Subjective refractions were also obtained with low-pass and high-pass stimuli and using “darker” and “sharper” subjective criteria. Results Subjective refractions for stimuli containing high spatial frequencies focus a near paraxial region of the pupil and are affected only slightly by level of Seidel spherical aberration, degree of pupil apodisation and pupil diameter, and generally focused a radius of about 1 to 1.5 mm from the pupil centre. Low spatial frequency refractions focus a marginal region of the pupil, and are significantly affected by level of spherical aberration, amount of pupil apodisation, and pupil size. Clinical refractions that employ the “darker” or “sharper” subjective criteria bias the patient to use lower or higher spatial frequencies respectively. Conclusions In the presence of significant levels of spherical aberration, the pupil size independence of subjective refractions occurs with or without Stiles Crawford apodisation for refractions that optimise high spatial frequency content in the image. If low spatial frequencies are optimised by a subjective refraction, spherical refractive error varies with spherical aberration, pupil size, and level of apodisation. As light levels drop from photopic to scotopic, therefore, we expect a shift from pupil size independent to pupil size dependent subjective refractions. Emphasising a “sharper” criterion during subjective refractions will improve image quality for high spatial frequencies and generate pupil size independent refractions. PMID:24397356
Helmreich, S; Wechsler, B; Hauser, R; Gygax, L
2016-03-01
In barns with an automatic milking system (AMS), both the milking frequency and the number of nighttime milkings vary between cows. A low milking frequency might indicate problems in gaining access to the milking unit. Also, nighttime lighting in the waiting area of the AMS and in the milking unit increases exposure to light at night and could suppress nocturnal melatonin synthesis. These effects could result in increased stress, suppressed immune response, and poor udder health. A total of 125 cows (14-16/farm) on 8 farms with AMS were selected based on their average milking frequency. Eight to 10 saliva samples per cow were taken over the course of 4 days, and cortisol, IgA and melatonin concentrations were determined. Somatic cell counts (SCC) were determined in milk samples. Milking frequency had no significant relationship with mean cortisol and IgA levels, but a higher milking frequency tended to be associated with lower SCC levels. Nocturnal melatonin levels tended to be negatively associated with the number of nighttime milkings. In conclusion, no indication of increased stress or reduced immune defense was found in relation to milking frequency on farms with an AMS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deng, Zhao, E-mail: zhao.deng@foxmail.com; Waltz, R. E.
2015-05-15
This paper presents numerical simulations of the nonlinear cyclokinetic equations in the cyclotron harmonic representation [R. E. Waltz and Zhao Deng, Phys. Plasmas 20, 012507 (2013)]. Simulations are done with a local flux-tube geometry and with the parallel motion and variation suppressed using a newly developed rCYCLO code. Cyclokinetic simulations dynamically follow the high-frequency ion gyro-phase motion which is nonlinearly coupled into the low-frequency drift-waves possibly interrupting and suppressing gyro-averaging and increasing the transport over gyrokinetic levels. By comparing the more fundamental cyclokinetic simulations with the corresponding gyrokinetic simulations, the breakdown of gyrokinetics at high turbulence levels is quantitatively testedmore » over a range of relative ion cyclotron frequency 10 < Ω*{sup }< 100 where Ω*{sup }= 1/ρ*, and ρ* is the relative ion gyroradius. The gyrokinetic linear mode rates closely match the cyclokinetic low-frequency rates for Ω*{sup }> 5. Gyrokinetic transport recovers cyclokinetic transport at high relative ion cyclotron frequency (Ω*{sup }≥ 50) and low turbulence level as required. Cyclokinetic transport is found to be lower than gyrokinetic transport at high turbulence levels and low-Ω* values with stable ion cyclotron (IC) modes. The gyrokinetic approximation is found to break down when the density perturbations exceed 20%. For cyclokinetic simulations with sufficiently unstable IC modes and sufficiently low Ω*{sup }∼ 10, the high-frequency component of cyclokinetic transport level can exceed the gyrokinetic transport level. However, the low-frequency component of the cyclokinetic transport and turbulence level does not exceed that of gyrokinetics. At higher and more physically relevant Ω*{sup }≥ 50 values and physically realistic IC driving rates, the low-frequency component of the cyclokinetic transport and turbulence level is still smaller than that of gyrokinetics. Thus, the cyclokinetic simulations do not account for the so-called “L-mode near edge short fall” seen in some low-frequency gyrokinetic transport and turbulence simulations.« less
Santovito, Alfredo; Cervella, Piero; Delpero, Massimiliano
2016-05-01
The increased exposure to environmental pollutants has led to the awareness of the necessity for constant monitoring of human populations, especially those living in urban areas. This study evaluated the background levels of genomic damage in a sample of healthy subjects living in the urban area of Turin (Italy). The association between DNA damage with age, sex and GSTs polymorphisms was assessed. One hundred and one individuals were randomly sampled. Sister Chromatid Exchanges (SCEs) and Chromosomal Aberrations (CAs) assays, as well as genotyping of GSTT1 and GSTM1 genes, were performed. Mean values of SCEs and CAs were 5.137 ± 0.166 and 0.018 ± 0.002, respectively. Results showed age and gender associated with higher frequencies of these two cytogenetic markers. The eldest subjects (51-65 years) showed significantly higher levels of genomic damage than younger individuals. GSTs polymorphisms did not appear to significantly influence the frequencies of either markers. The CAs background frequency observed in this study is one of the highest reported among European populations. Turin is one of the most polluted cities in Europe in terms of air fine PM10 and ozone and the clastogenic potential of these pollutants may explain the high frequencies of chromosomal rearrangements reported here.
Toliver-Sokol, Marisol; Murray, Caitlin B; Wilson, Anna C; Lewandowski, Amy; Palermo, Tonya M
2011-07-01
There is limited research describing the patterns of healthcare utilization in adolescents with chronic pain. This study describes healthcare utilization in a clinical chronic pain sample, and compares the patterns of service use of this group to a community sample with intermittent pain complaints. We also investigated demographic and clinical factors that predicted healthcare visits and medication use in the clinical sample. Data on 117 adolescents (aged 12-18; n = 59 clinical pain sample, n = 58 community) were collected. Caregivers and adolescents reported on sociodemographics, medical visits, current medications, pain, activity limitations, and depression. As hypothesized, the clinical pain sample had higher rates of healthcare consultation on all types of medical visits (general, specialty care, complementary medicine, mental health, OT/PT), and higher medication use compared to the community sample. Regression analyses revealed that higher annual income, greater pain frequency, and higher levels of caregiver-reported activity limitations were associated with a greater number of healthcare visits for the total sample. Within the clinical pain sample, higher pain frequency and greater activity limitations (caregiver report) predicted more specialty care visits. Additionally, higher income and greater levels of depressive symptoms predicted a higher number of prescribed medications. This study contributes to the limited available data on health service and medication use in a clinical chronic pain sample versus a community sample of adolescents. We also identify clinical factors (pain frequency, parent-reported activity limitations, depressive symptoms) and demographic factors (gender, income) associated with healthcare utilization. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.
SALIMI, SAEEDEH; NOORA, MEHRANGIZ; NABIZADEH, SIMA; REZAEI, MAHNAZ; SHAHRAKI, HOSSAIN; MILAD, MOHAMMADOO-KHORASSANI; NAGHAVI, ANOOSH; FARAJIAN-MASHHADI, FARZANEH; ZAKERI, ZAHRA; SANDOUGHI, MAHNAZ
2016-01-01
Osteopontin (OPN) is a chemokine-like glycoprotein that has a prominent role in regulating inflammation and immunity. OPN polymorphisms and elevated OPN levels are associated with systemic lupus erythematosus (SLE) in several populations. The aim of present study was to evaluate the association between the OPN rs1126616 polymorphism and OPN level with SLE susceptibility. A total of 163 SLE patients and 180 age-, gender- and ethnically matched controls were genotyped for the rs1126616 polymorphism by the polymerase chain reaction-restriction fragment length polymorphism method. Serum OPN levels were assayed by the enzyme-linked immunosorbent assay. There was no association between the OPN rs1126616 C/T polymorphism and SLE. The frequency of the OPN rs1126616 CT genotype was significantly higher in SLE patients with nephritis compared to SLE patients without nephritis and controls. Additionally, the frequency of TT genotypes was higher in SLE patients with nephritis compared to controls. The serum OPN levels were significantly higher in SLE patients compared to controls (50.6±22 vs. 35.6±15.8 ng/ml, P<0.001). Increased serum OPN levels were observed in SLE patients with lupus nephritis and joint symptoms. There was no correlation between OPN levels and the OPN rs1126616 polymorphism. The present data suggest that the CT and TT genotypes of the OPN rs1126616 polymorphism could be a risk factor for lupus nephritis. The OPN level is associated with SLE and certain SLE manifestations. However, there was no association between the OPN rs1126616 C/T polymorphism and SLE susceptibility. PMID:26998275
Scaling of Yb-Fiber Frequency Combs
NASA Astrophysics Data System (ADS)
Ruehl, Axel; Marcinkevicius, Andrius; Fermann, Martin E.; Hartl, Ingmar
2010-06-01
Immediately after their introduction in 1999, femtosecond laser frequency combs revolutionized the field of precision optical frequency metrology and are key elements in many experiments. Frequency combs based on femtosecond Er-fiber lasers based were demonstrated in 2005, allowing additionally rugged, compact set-ups and reliable unattended long-term operation. The introduction of Yb-fiber technology led to an dramatic improvement in fiber-comb performance in various aspects. Low-noise Yb-fiber femtosecond oscillators enabled a reduction of relative comb tooth linewidth to the sub-Hz level as well as scaling of the fundamental comb spacings up to 1 GHz. This is beneficial for any frequency-domain comb application due to the higher power per comb-mode. Many spectroscopic applications require, however, frequency combs way beyond the wavelength range accessible with broad band laser materials, so nonlinear conversion and hence higher peak intensity is required. We demonstrated power scaling of Yb-fiber frequency combs up to 80 W average power in a strictly linear chirped-pulse amplification schemes compatible with low-noise phase control. These high-power Yb-fiber-frequency combs facilitated not only the extension to the mid-IR spectral region. When coupled to a passive enhancement cavity, the average power can be further scaled to the kW-level opening new capabilities for XUV frequency combs via high-harmonic generation. All these advances of fiber-based frequency combs will trigger many novel applications both in fundamental and applied sciences. Schibli et al., Nature Photonics 2 355 (2008). Hartl et al., MF9 in Advanced Solid-State Photonics. 2009, Optical Society of America. Ruehl et al., AWC7 in Advanced Solid-State Photonics. 2010, Optical Society of America. Adler et al., Optics Letters 34 1330 (2009). Yost et al., Nature Physics 5 815 (2009).
Frequency modulation detection in cochlear implant subjects
NASA Astrophysics Data System (ADS)
Chen, Hongbin; Zeng, Fan-Gang
2004-10-01
Frequency modulation (FM) detection was investigated in acoustic and electric hearing to characterize cochlear-implant subjects' ability to detect dynamic frequency changes and to assess the relative contributions of temporal and spectral cues to frequency processing. Difference limens were measured for frequency upward sweeps, downward sweeps, and sinusoidal FM as a function of standard frequency and modulation rate. In electric hearing, factors including electrode position and stimulation level were also studied. Electric hearing data showed that the difference limen increased monotonically as a function of standard frequency regardless of the modulation type, the modulation rate, the electrode position, and the stimulation level. In contrast, acoustic hearing data showed that the difference limen was nearly a constant as a function of standard frequency. This difference was interpreted to mean that temporal cues are used only at low standard frequencies and at low modulation rates. At higher standard frequencies and modulation rates, the reliance on the place cue is increased, accounting for the better performance in acoustic hearing than for electric hearing with single-electrode stimulation. The present data suggest a speech processing strategy that encodes slow frequency changes using lower stimulation rates than those typically employed by contemporary cochlear-implant speech processors. .
Beamer, Paloma; Key, Maya E; Ferguson, Alesia C; Canales, Robert A; Auyeung, Willa; Leckie, James O
2008-10-01
This study was conducted to describe exposure prone behaviors of infants and toddlers in the farmworker community. Analysis of hand and mouth contact frequencies and durations aids understanding of how children interact with their environment and are exposed via contact with surfaces. All 23 participating children (8 female infants, 5 male infants, 5 female toddlers and 5 male toddlers) lived with at least one farmworker. Children were videotaped at home for 2-6 h. Video footage was translated into micro-level activity time series (MLATS) for both hands and the mouth. MLATS were processed to calculate hourly duration in microenvironments, contact frequency, hourly contact duration and median contact duration. The median hourly duration spent indoors was 53 min/h. The median hand-to-mouth frequency was 15.2 events/h and the median object-to-mouth frequency was 27.2 events/h. The hourly mouthing duration was 1.2 and 2.2 min/h with the hands and objects, respectively. The median mouthing duration with hands and objects was 2 s. The median contact frequency for both hands combined was 689.4 events/h with an hourly contact duration of 100.5 min/h and a median contact duration of 3s. Infants had higher mouthing frequencies with non-dietary objects while toddlers had higher mouthing frequencies with objects associated with pica (i.e., paper). Boys had higher contact frequencies while girls had longer contact durations. These sub-group differences indicate factors such as age and gender should be accounted for when conducting exposure assessments. Contact frequencies in this study are higher than current US EPA recommendations, questioning their protective value for infants and toddlers.
Beamer, Paloma; Key, Maya E.; Ferguson, Alesia C.; Canales, Robert A.; Auyeung, Willa; Leckie, James O.
2008-01-01
This study was conducted to describe exposure prone behaviors of infants and toddlers in the farmworker community. Analysis of hand and mouth contact frequencies and durations aids understanding of how children interact with their environment and are exposed via contact with surfaces. All 23 participating children (8 female infants, 5 male infants, 5 female toddlers and 5 male toddlers) lived with at least one farmworker. Children were videotaped at home for 2–6 hours. Video footage was translated into micro- level activity time series (MLATS) for both hands and the mouth. MLATS were processed to calculate hourly duration in microenvironments, contact frequency, hourly contact duration and median contact duration. The median hourly duration spent indoors was 53 min/hr. The median hand-to-mouth frequency was 15.2 events/hr and the median object-to-mouth frequency was 27.2 events/hr. The hourly mouthing duration was 1.2 and 2.2 min/hr with the hands and objects respectively. The median mouthing duration with hands and objects was 2 seconds. The median contact frequency for both hands combined was 689.4 events/hr with an hourly contact duration of 100.5 min/hr and a median contact duration of 3 seconds. Infants had higher mouthing frequencies with non-dietary objects while toddlers had higher mouthing frequencies with objects associated with pica (i.e., paper). Boys had higher contact frequencies while girls had longer contact durations. These sub-group differences indicate factors such as age and gender should be accounted for when conducting exposure assessments. Contact frequencies in this study are higher than current U.S. EPA recommendations, questioning their protective value for infants and toddlers. PMID:18723168
Sassani, Farrokh
2014-01-01
The simulation results for electromagnetic energy harvesters (EMEHs) under broad band stationary Gaussian random excitations indicate the importance of both a high transformation factor and a high mechanical quality factor to achieve favourable mean power, mean square load voltage, and output spectral density. The optimum load is different for random vibrations and for sinusoidal vibration. Reducing the total damping ratio under band-limited random excitation yields a higher mean square load voltage. Reduced bandwidth resulting from decreased mechanical damping can be compensated by increasing the electrical damping (transformation factor) leading to a higher mean square load voltage and power. Nonlinear EMEHs with a Duffing spring and with linear plus cubic damping are modeled using the method of statistical linearization. These nonlinear EMEHs exhibit approximately linear behaviour under low levels of broadband stationary Gaussian random vibration; however, at higher levels of such excitation the central (resonant) frequency of the spectral density of the output voltage shifts due to the increased nonlinear stiffness and the bandwidth broadens slightly. Nonlinear EMEHs exhibit lower maximum output voltage and central frequency of the spectral density with nonlinear damping compared to linear damping. Stronger nonlinear damping yields broader bandwidths at stable resonant frequency. PMID:24605063
Workload assessment of surgeons: correlation between NASA TLX and blinks.
Zheng, Bin; Jiang, Xianta; Tien, Geoffrey; Meneghetti, Adam; Panton, O Neely M; Atkins, M Stella
2012-10-01
Blinks are known as an indicator of visual attention and mental stress. In this study, surgeons' mental workload was evaluated utilizing a paper assessment instrument (National Aeronautics and Space Administration Task Load Index, NASA TLX) and by examining their eye blinks. Correlation between these two assessments was reported. Surgeons' eye motions were video-recorded using a head-mounted eye-tracker while the surgeons performed a laparoscopic procedure on a virtual reality trainer. Blink frequency and duration were computed using computer vision technology. The level of workload experienced during the procedure was reported by surgeons using the NASA TLX. A total of 42 valid videos were recorded from 23 surgeons. After blinks were computed, videos were divided into two groups based on the blink frequency: infrequent group (≤ 6 blinks/min) and frequent group (more than 6 blinks/min). Surgical performance (measured by task time and trajectories of tool tips) was not significantly different between these two groups, but NASA TLX scores were significantly different. Surgeons who blinked infrequently reported a higher level of frustration (46 vs. 34, P = 0.047) and higher overall level of workload (57 vs. 47, P = 0.045) than those who blinked more frequently. The correlation coefficients (Pearson test) between NASA TLX and the blink frequency and duration were -0.17 and 0.446. Reduction of blink frequency and shorter blink duration matched the increasing level of mental workload reported by surgeons. The value of using eye-tracking technology for assessment of surgeon mental workload was shown.
Reas, Deborah Lynn; Rø, Øyvind
2018-01-01
This study investigated subtype differences in eating disorder-specific impairment in a treatment-seeking sample of individuals with anorexia nervosa (AN). The Clinical Impairment Assessment (CIA) and the Eating Disorder Examination-Questionnaire (EDE-Q) were administered to 142 patients. Of these, 54.9% were classified as restricting type (AN-R) and 45.1% were classified as binge-eating/purging type (AN-B/P) based on an average weekly occurrence of binge eating and/or purging episodes (≥4 episodes/28days). Individuals with AN-B/P exhibited higher levels of core ED psychopathology (dietary restraint, eating concern, shape/weight concerns) in addition to the expected higher frequency of binge/purge episodes. No significant differences existed between AN subtypes in the severity of ED-related impairment. Weight/shape concerns and binge eating frequency significantly predicted level of impairment. Differential associations were observed between the type of ED pathology that significantly contributed to impairment according to AN subtype. Although those with AN-B/P displayed higher levels of core attitudinal and behavioral ED pathology than AN-R, no significant differences in ED-specific impairment were found between AN subtypes. Eating disorder-related impairment in AN was not related to the severity of underweight or purging behaviors, but was uniquely and positively associated with weight/shape concerns and binge eating frequency. Copyright © 2018 Elsevier Ltd. All rights reserved.
Buss, Emily; Porter, Heather L.; Leibold, Lori J.; Grose, John H.; Hall, Joseph W.
2016-01-01
Objectives Detection thresholds in quiet become adult-like earlier in childhood for high than low frequencies. When adults listen for sounds near threshold, they tend to engage in behaviors that reduce physiologic noise (e.g., quiet breathing), which is predominantly low frequency. Children may not suppress self-generated noise to the same extent as adults, such that low-frequency self-generated noise elevates thresholds in the associated frequency regions. This possibility was evaluated by measuring noise levels in the ear canal simultaneous with adaptive threshold estimation. Design Listeners were normal-hearing children (4.3-16.0 yrs) and adults. Detection thresholds were measured adaptively for 250-, 1000- and 4000-Hz pure tones using a three-alternative forced-choice procedure. Recordings of noise in the ear canal were made while the listeners performed this task, with the earphone and microphone routed through a single foam insert. Levels of self-generated noise were computed in octave-wide bands. Age effects were evaluated for four groups: 4- to 6-year-olds, 7- to 10-year-olds, 11- to 16-year-olds, and adults. Results Consistent with previous data, the effect of child age on thresholds was robust at 250 Hz and fell off at higher frequencies; thresholds of even the youngest listeners were similar to adults’ at 4000 Hz. Self-generated noise had a similar low-pass spectral shape for all age groups, although the magnitude of self-generated noise was higher in younger listeners. If self-generated noise impairs detection, then noise levels should be higher for trials associated with the wrong answer than the right answer. This association was observed for all listener groups at the 250-Hz signal frequency. For adults and older children, this association was limited to the noise band centered on the 250-Hz signal. For the two younger groups of children, this association was strongest at the signal frequency, but extended to bands spectrally remote from the 250-Hz signal. For the 1000-Hz signal frequency, there was a broadly tuned association between noise and response only for the two younger groups of children. For the 4000-Hz signal frequency, only the youngest group of children demonstrated an association between responses and noise levels, and this association was particularly pronounced for bands below the signal frequency. Conclusions These results provide evidence that self-generated noise plays a role in the prolonged development of low-frequency detection thresholds in quiet. Some aspects of the results are consistent with the possibility that self-generated noise elevates thresholds via energetic masking, particularly at 250 Hz. The association between behavioral responses and noise spectrally remote from the signal frequency is also consistent with the idea that self-generated noise may also reflect contributions of more central factors (e.g., inattention to the task). Evaluation of self-generated noise could improve diagnosis of minimal or mild hearing loss. PMID:27438873
Improving sound absorption property of polyurethane foams doped with natural fiber
NASA Astrophysics Data System (ADS)
Azahari, M. Shafiq M.; Rus, Anika Zafiah M.; Taufiq Zaliran, M.; Kormin, Shaharuddin
2017-08-01
This study investigates the acoustics behavior of wood fibre filler of Red Meranti - filled polyurethane foam as a sound absorbing material. Three different thicknesses have been selected which is 10 mm, 20 mm and 30 mm. By choosing percentage loading of Red Meranti (RM) wood fibre of 5%, 10%, 15% and 20% added with polymer foam is namely as polymer foam (PF) composites of PF5%, PF10%, PF15% and PF20%. The sound absorption coefficient (α) and pore structure of the foam samples have been examined by using Impedance Tube test and Scanning Electron Microscopy (SEM). The results revealed that the highest thickness of highest filler loading (PF20%) gives higher sound absorption coefficient (α). The absorption frequency level is observed at 0.9922 and 0.99889 which contributed from low and high frequency absorption level respectively. The smallest pores size structure was observed with highest filler loading of PF. The higher the thickness and the higher the percentage loading of wood filler gives smaller pore structure, consequently, increased the sound absorption coefficient level.
Comparison of Fine Structures of Electron Cyclotron Harmonic Emissions in Aurora
NASA Astrophysics Data System (ADS)
Labelle, J. W.; Dundek, M.
2015-12-01
Recent discoveries of emissions at four and five times the electron cyclotron frequency in aurora occuring under daylit conditions motivated the modification of radio receivers at South Pole Station, Antarctica, to measure fine structure of such emissions during two consecutive austral summers, 2013-4 and 2014-5. The experiment recorded 347 emission events over 376 days of observation. The seasonal distribution of these events revealed that successively higher harmonics require higher solar zenith angles for occurrence, as expected if they are generated at locations where the upper hybrid frequency matches the cyclotron harmonic, which for higher harmonics requires higher electron densities which are associated with higher solar zenith angles. Detailed examination of 21 cases in which two harmonics occur simultaneously showed that only rarely, about ten percent of the time, are the frequencies of the fine structures of the emissions in exact integer ratio (e.g., 3:2, 4:3, or 5:4 depending on which combination of harmonics is observed). In the remaining approximately ninety percent of the cases, the higher harmonic occurred at a lower ratio than the appropriate integer ratio, as expected if the harmonics are generated independently at their separate matching conditions in the bottomside ionosphere, where the upper hybrid frequency increases with altitude while the gyroharmonics decrease with altitude. (The bottomside is the most likely source of the emissions, since from there the mode converted Z-modes have access to ground-level.) Taken together, these results suggest that the dominant mechanism for the higher harmonics is independent generation at locations where the upper hybrid frequency matches each harmonic, i.e., at a separate source altitude for each harmonic. Generation of higher harmonics through coalescence of lower harmonic waves explains at most a small minority of events.
Detection of high-frequency energy level changes in speech and singing
Monson, Brian B.; Lotto, Andrew J.; Story, Brad H.
2014-01-01
Previous work has shown that human listeners are sensitive to level differences in high-frequency energy (HFE) in isolated vowel sounds produced by male singers. Results indicated that sensitivity to HFE level changes increased with overall HFE level, suggesting that listeners would be more “tuned” to HFE in vocal production exhibiting higher levels of HFE. It follows that sensitivity to HFE level changes should be higher (1) for female vocal production than for male vocal production and (2) for singing than for speech. To test this hypothesis, difference limens for HFE level changes in male and female speech and singing were obtained. Listeners showed significantly greater ability to detect level changes in singing vs speech but not in female vs male speech. Mean differences limen scores for speech and singing were about 5 dB in the 8-kHz octave (5.6–11.3 kHz) but 8–10 dB in the 16-kHz octave (11.3–22 kHz). These scores are lower (better) than those previously reported for isolated vowels and some musical instruments. PMID:24437780
Immune perturbations in HIV–1-infected individuals who make broadly reactive neutralizing antibodies
Moody, M. Anthony; Pedroza-Pacheco, Isabela; Vandergrift, Nathan A.; Chui, Cecilia; Lloyd, Krissey E.; Parks, Robert; Soderberg, Kelly A.; Ogbe, Ane T.; Cohen, Myron S.; Liao, Hua-Xin; Gao, Feng; McMichael, Andrew J.; Montefiori, David C.; Verkoczy, Laurent; Kelsoe, Garnett; Huang, Jinghe; Shea, Patrick R.; Connors, Mark; Borrow, Persephone; Haynes, Barton F.
2017-01-01
Induction of broadly neutralizing antibodies (bnAbs) is a goal of HIV-1 vaccine development. BnAbs occur in some HIV-1-infected individuals and frequently have characteristics of autoantibodies. Here we have studied cohorts of HIV-1-infected individuals that made bnAbs and compared them to those who did not do so, and determined immune traits associated with the ability to produce bnAbs. HIV-1-infected individuals with bnAbs had a higher frequency of blood autoantibodies, a lower frequency of regulatory CD4+ T cells, a higher frequency of circulating memory T follicular helper CD4+ cells and a higher T regulatory cell level of programmed cell death-1 expression compared to HIV-1-infected individuals without bnAbs. Thus, induction of HIV-1 bnAbs may require vaccination regimens that transiently mimic immunologic perturbations in HIV-1-infected individuals. PMID:28783677
Kelishadi, Roya; Mirmoghtadaee, Parisa; Qorbani, Mostafa; Motlagh, Mohammad Esmaeil; Heshmat, Ramin; Taslimi, Mahnaz; Mahmoudarabi, Minoosadat; Ardalan, Gelayol; Larijani, Bagher
2013-01-01
Background: A growing body of evidence supports an association between oral health and cardiovascular diseases and diabetes in adults. This study aimed to investigate the relationship between tooth brushing frequency and cardiometabolic risk factors in adolescents. Methods: This nationwide population-based study was conducted among 5258 Iranian students, aged 10-18 years, living in urban and rural areas of 27 provinces in Iran. The association of tooth brushing frequency was assessed with anthropometric indexes and cardiometabolic risk factors after adjustment for potential confounders. Results: Higher frequency of tooth brushing was associated with lower mean levels of low-density lipoprotein cholesterol (LDL-C) in both genders (P < 0.0001) and lower frequency of elevated LDL-C in girls (P = 0.03). The frequency of elevated blood pressure decreased with higher tooth brushing frequency in boys (P = 0.03). After adjustment for many potential cofounders such as age, gender, anthropometric indexes, screen time, socioeconomic status, and family history of non-communicable diseases, participants who washed their teeth at least once a day had lower risk of high LDL-C and low high-density lipoprotein cholesterol (HDL-C) levels in comparison to those who reported lower frequency of tooth brushing; some different associations were observed among girls and boys. Conclusions: Our findings suggest an independent and protective role of teeth brushing frequency for some cardiometabolic risk factors in adolescents. Increasing both the general health awareness and improving oral health should be considered in primordial and primary prevention of non-communicable diseases. PMID:23626883
[Frequency of chromosome aberrations in residents of the Semipalatinsk Oblast].
Gubitskaia, E G; Akhmatullina, N B; Vsevolodov, E B; Bishnevskaia, S S; Sharipov, I K; Cherednichenko, O G
1999-06-01
Cytogenetic analysis of the population of the Beskaragai district of the Semipalatinsk oblast adjacent to the territory of the nuclear test site was conducted by means of an ecological genetic questionnaire and cytogenetic examination of metaphase chromosomes. An increase in the total mutation level in the region was observed. The frequency of chromosome aberrations among the population of the Beskaragai district (3.2%) was statistically significantly (about 1.5 times) higher than the background levels in the clear regions (from 1 to 2%). Furthermore, the frequency of aberrations in adolescents was comparable with that in the adults. The spectrum of chromosome aberrations pointed to a significant contribution of radiation component to the mutagenesis.
Regional price differences and food consumption frequency among elementary school children.
Sturm, R; Datar, A
2011-03-01
Food prices may affect diet and weight gain among youth and lead to geographic disparities in obesity. This paper examines the association between regional prices and consumption frequency of fruit/vegetables and snack items among elementary school children in the USA. Observational study using individual-level survey data of fifth-grade children (average age 11 years) and regional food prices based on store visits in 2004. Dependent variables are self-reported consumption frequency in fifth grade; primary explanatory variables are metropolitan area food prices relative to cost of living. Multivariate regression analysis. Price variation across metropolitan areas exists, and lower real prices for vegetables and fruits predict significantly higher intake frequency. Higher dairy prices predict lower frequency of milk consumption, while higher meat prices predict increased milk consumption. Similar price effects were not found for fast food or soft drink consumption. The geographic variation in food prices across the USA is sufficiently large to affect dietary patterns among youth for fruit, vegetables and milk. The price variation is either too small to affect children's consumption frequency of fast food or soft drinks, or the consumption of these foods is less price sensitive. Copyright © 2010 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Regional price differences and food consumption frequency among elementary school children
Sturm, R.; Datar, A.
2010-01-01
SUMMARY Objective Food prices may affect diet and weight gain among youth and lead to geographic disparities in obesity. This paper examines the association between regional prices and consumption frequency of fruit/vegetables and snack items among elementary school children in the USA. Study design Observational study using individual-level survey data of fifth-grade children (average age 11 years) and regional food prices based on store visits in 2004. Methods Dependent variables are self-reported consumption frequency in fifth grade; primary explanatory variables are metropolitan area food prices relative to cost of living. Multivariate regression analysis. Results Price variation across metropolitan areas exists, and lower real prices for vegetables and fruits predict significantly higher intake frequency. Higher dairy prices predict lower frequency of milk consumption, while higher meat prices predict increased milk consumption. Similar price effects were not found for fast food or soft drink consumption. Discussion The geographic variation in food prices across the USA is sufficiently large to affect dietary patterns among youth for fruit, vegetables and milk. This suggests that either the price variation is too small to affect children’s consumption frequency of fast food or soft drinks, or that the consumption of these foods is less price sensitive. PMID:21315395
Derryberry, Elizabeth P; Danner, Raymond M; Danner, Julie E; Derryberry, Graham E; Phillips, Jennifer N; Lipshutz, Sara E; Gentry, Katherine; Luther, David A
2016-01-01
Soundscapes pose both evolutionarily recent and long-standing sources of selection on acoustic communication. We currently know more about the impact of evolutionarily recent human-generated noise on communication than we do about how natural sounds such as pounding surf have shaped communication signals over evolutionary time. Based on signal detection theory, we hypothesized that acoustic phenotypes will vary with both anthropogenic and natural background noise levels and that similar mechanisms of cultural evolution and/or behavioral flexibility may underlie this variation. We studied song characteristics of white-crowned sparrows (Zonotrichia leucophrys nuttalli) across a noise gradient that includes both anthropogenic and natural sources of noise in San Francisco and Marin counties, California, USA. Both anthropogenic and natural soundscapes contain high amplitude low frequency noise (traffic or surf, respectively), so we predicted that birds would produce songs with higher minimum frequencies in areas with higher amplitude background noise to avoid auditory masking. We also anticipated that song minimum frequencies would be higher than the projected lower frequency limit of hearing based on site-specific masking profiles. Background noise was a strong predictor of song minimum frequency, both within a local noise gradient of three urban sites with the same song dialect and cultural evolutionary history, and across the regional noise gradient, which encompasses 11 urban and rural sites, several dialects, and several anthropogenic and natural sources of noise. Among rural sites alone, background noise tended to predict song minimum frequency, indicating that urban sites were not solely responsible for driving the regional pattern. These findings support the hypothesis that songs vary with local and regional soundscapes regardless of the source of noise. Song minimum frequency from five core study sites was also higher than the lower frequency limit of hearing at each site, further supporting the hypothesis that songs vary to transmit through noise in local soundscapes. Minimum frequencies leveled off at noisier sites, suggesting that minimum frequencies are constrained to an upper limit, possibly to retain the information content of wider bandwidths. We found evidence that site noise was a better predictor of song minimum frequency than territory noise in both anthropogenic and natural soundscapes, suggesting that cultural evolution rather than immediate behavioral flexibility is responsible for local song variation. Taken together, these results indicate that soundscapes shape song phenotype across both evolutionarily recent and long-standing soundscapes.
Derryberry, Graham E.; Phillips, Jennifer N.; Lipshutz, Sara E.; Gentry, Katherine; Luther, David A.
2016-01-01
Soundscapes pose both evolutionarily recent and long-standing sources of selection on acoustic communication. We currently know more about the impact of evolutionarily recent human-generated noise on communication than we do about how natural sounds such as pounding surf have shaped communication signals over evolutionary time. Based on signal detection theory, we hypothesized that acoustic phenotypes will vary with both anthropogenic and natural background noise levels and that similar mechanisms of cultural evolution and/or behavioral flexibility may underlie this variation. We studied song characteristics of white-crowned sparrows (Zonotrichia leucophrys nuttalli) across a noise gradient that includes both anthropogenic and natural sources of noise in San Francisco and Marin counties, California, USA. Both anthropogenic and natural soundscapes contain high amplitude low frequency noise (traffic or surf, respectively), so we predicted that birds would produce songs with higher minimum frequencies in areas with higher amplitude background noise to avoid auditory masking. We also anticipated that song minimum frequencies would be higher than the projected lower frequency limit of hearing based on site-specific masking profiles. Background noise was a strong predictor of song minimum frequency, both within a local noise gradient of three urban sites with the same song dialect and cultural evolutionary history, and across the regional noise gradient, which encompasses 11 urban and rural sites, several dialects, and several anthropogenic and natural sources of noise. Among rural sites alone, background noise tended to predict song minimum frequency, indicating that urban sites were not solely responsible for driving the regional pattern. These findings support the hypothesis that songs vary with local and regional soundscapes regardless of the source of noise. Song minimum frequency from five core study sites was also higher than the lower frequency limit of hearing at each site, further supporting the hypothesis that songs vary to transmit through noise in local soundscapes. Minimum frequencies leveled off at noisier sites, suggesting that minimum frequencies are constrained to an upper limit, possibly to retain the information content of wider bandwidths. We found evidence that site noise was a better predictor of song minimum frequency than territory noise in both anthropogenic and natural soundscapes, suggesting that cultural evolution rather than immediate behavioral flexibility is responsible for local song variation. Taken together, these results indicate that soundscapes shape song phenotype across both evolutionarily recent and long-standing soundscapes. PMID:27128443
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-24
... communication signals used by low frequency mysticetes when they occur near the noise band and thus reduce the communication space of animals (e.g., Clark et al. 2009) and cause increased stress levels (e.g., Foote et al... well as additional lower-powered and higher frequency survey equipment for collecting bathymetric and...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-21
... communication signals used by low frequency mysticetes when they occur near the noise band and thus reduce the communication space of animals (e.g., Clark et al. 2009) and cause increased stress levels (e.g., Foote et al... additional lower-powered and higher frequency survey equipment for collecting bathymetric and shallow sub...
Experimental investigation of outdoor propagation of finite-amplitude noise. [aircraft noise
NASA Technical Reports Server (NTRS)
Webster, D. A.; Blackstock, D. T.
1978-01-01
The outdoor propagation of finite amplitude acoustic waves was investigated using a conventional electroacoustic transmitter which was mounted on the ground and pointed upward in order to avoid ground reflection effects. The propagation path was parallel to a radio tower 85 m tall, whose elevator carried the receiving microphone. The observations and conclusions are as follows: (1) At the higher source levels nonlinear propagation distortion caused a strong generation of high frequency noise over the propagation path. For example, at 70 m for a frequency 2-3 octaves above the source noise band, the measured noise was up to 30 dB higher than the linear theory prediction. (2) The generation occurred in both the nearfield and the farfield of the transmitter. (3) At no measurement point was small-signal behavior established for the high requency noise. Calculations support the contention that the nonlinearity generated high frequency noise never becomes small-signal in its behavior, regardless of distance. (4) When measured spectra are scaled in frequency and level to make them comparable with spectra of actual jet noise, they are found to be well within the jet noise range. It is therefore entirely possible that nonlinear distortion affects jet noise.
Vibration characteristics of bone conducted sound in vitro.
Stenfelt, S; Håkansson, B; Tjellström, A
2000-01-01
A dry skull added with damping material was used to investigate the vibratory pattern of bone conducted sound. Three orthogonal vibration responses of the cochleae were measured, by means of miniature accelerometers, in the frequency range 0.1-10 kHz. The exciter was attached to the temporal, parietal, and frontal bones, one at the time. In the transmission response to the ipsilateral cochlea, a profound low frequency antiresonance (attenuation) was found, verified psycho-acoustically, and shown to yield a distinct lateralization effect. It was also shown that, for the ipsilateral side, the direction of excitation coincides with that of maximum response. At the contralateral cochlea, no such dominating response direction was found for frequencies above the first skull resonance. An overall higher response level was achieved, for the total energy transmission in general and specifically for the direction of excitation, at the ipsilateral cochlea when the transducer was attached to the excitation point closest to the cochlea. The transranial attenuation was found to be frequency dependent, with values from -5 to 10 dB for the energy transmission and -30 to 40 dB for measurements in a single direction, with a tendency toward higher attenuation at the higher frequencies.
Singh, Zorawar; Chadha, Pooja; Sharma, Suman
2013-01-01
Battery manufacturing workers are occupationally exposed to lead (Pb), which is a highly toxic heavy metal. The aim of this study was to investigate the blood lead levels (BLL) of 30 battery manufacturing workers and find the correlation between BLL, micronucleated cell (MNC) frequency, binucleated cell (BNC) frequency in buccal mucosal cells and malondialdehyde concentrations in serum. 30 subjects of the BMW group, exposed to lead, and 30 control subjects, matched with the exposed subjects with respect to age, socio-economic status, sex, diet, smoking and drinking habits, were monitored for this study. BLL was found to have highly significant difference between both the groups (P < 0.001). The serum MDA levels were observed at significantly higher levels (6.76 ± 3.26) for the exposed group as compared to the control group (2.10 ± 1.02; P < 0.001). Buccal micronucleus test showed that both MNC and BNC frequencies were higher among the workers, in comparison to the control subjects. A positive correlation has been found between BLL and all the parameters. Our results indicate an increased health associated risk for workers occupationally exposed to lead.
Sound pressure level in a municipal preschool
Kemp, Adriana Aparecida Tahara; Delecrode, Camila Ribas; Guida, Heraldo Lorena; Ribeiro, André Knap; Cardoso, Ana Claúdia Vieira
2013-01-01
Summary Aim: To evaluate the sound pressure level to which preschool students are exposed. Method: This was a prospective, quantitative, nonexperimental, and descriptive study. To achieve the aim of the study we used an audio dosimeter. The sound pressure level (SPL) measurements were obtained for 2 age based classrooms. Preschool I and II. The measurements were obtained over 4 days in 8-hour sessions, totaling 1920 minutes. Results: Compared with established standards, the SPL measured ranged from 40.6 dB (A) to 105.8 dB (A). The frequency spectrum of the SPL was concentrated in the frequency range between 500 Hz and 4000 Hz. The older children produced higher SPLs than the younger ones, and the levels varied according to the activity performed. Painting and writing were the quietest activities, while free activities period and games were the noisiest. Conclusion: The SPLs measured at the preschool were higher and exceeded the maximum permitted level according to the reference standards. Therefore, the implementation of actions that aim to minimize the negative impact of noise in this environment is essential. PMID:25992013
Sound Environments Surrounding Preterm Infants Within an Occupied Closed Incubator.
Shimizu, Aya; Matsuo, Hiroya
2016-01-01
Preterm infants often exhibit functional disorders due to the stressful environment in the neonatal intensive care unit (NICU). The sound pressure level (SPL) in the NICU is often much higher than the levels recommended by the American Academy of Pediatrics. Our study aims to describe the SPL and sound frequency levels surrounding preterm infants within closed incubators that utilize high frequency oscillation (HFO) or nasal directional positive airway pressure (nasal-DPAP) respiratory settings. This is a descriptive research study of eight preterm infants (corrected age<33 weeks) exposed to the equipment when placed in an incubator. The actual noise levels were observed and the results were compared to the recommendations made by neonatal experts. Increased noise levels, which have reported to affect neonates' ability to self-regulate, could increase the risk of developing attention deficit disorder, and may result in tachycardia, bradycardia, increased intracranial pressure, and hypoxia. The care provider should closely assess for adverse effects of higher sound levels generated by different modes of respiratory support and take measures to ensure that preterm infants are protected from exposure to noise exceeding the optimal safe levels. Copyright © 2016 Elsevier Inc. All rights reserved.
Engel, Tal; Ben-Horin, Shomron; Beer-Gabel, Marc
2015-10-01
Autonomic dysfunction has been implicated in Crohn's disease (CD). We aimed to investigate heart rate variability (HRV) as a marker of possible autonomic imbalance in patients with CD. Thirty patients with CD and 30 age- and gender-matched healthy controls were enrolled in a prospective cohort study and underwent HRV study. Anxiety level was scored using the STAI questionnaire and CD clinical activity was assessed by Harvey-Bradshaw index. Blood tests including inflammatory markers were obtained for all participants. CD subjects had lower mean blood pressure (85.51 ± 11.07 mm Hg, 91.51 ± 6.99, P = 0.015) and albumin and significantly higher CRP and IL-6 compared with controls (P < 0.002 for all comparisons). Mean HRV values of very low-frequency power and low-frequency power components were significantly lower among CD subjects (P = 0.038 and 0.027, respectively), implying a predominant sympathetic tone. Anxiety level scores were significantly higher among patients with CD for both state anxiety (P = 0.001) and trait anxiety (P < 0.0001). However, patients with active disease had similar anxiety scores as patients in remission, yet had a significantly lower BMI, lower albumin level, and higher CRP and IL-6 levels (P < 0.05 for all comparisons). Moreover, despite similar anxiety scores, patients with active disease had higher pulse rate (P = 0.02) and lower HRV indexes, which correlated with albumin levels(r = 0.7, P = 0.001). Although patients with CD have higher anxiety levels compared with controls, they exhibit depressed HRV independent of this anxiety state and in direct correlation with disease activity and inflammatory markers. These observations suggest an inherent imbalance of autonomic function associated with active inflammation.
Estimate of higher order ionospheric errors in GNSS positioning
NASA Astrophysics Data System (ADS)
Hoque, M. Mainul; Jakowski, N.
2008-10-01
Precise navigation and positioning using GPS/GLONASS/Galileo require the ionospheric propagation errors to be accurately determined and corrected for. Current dual-frequency method of ionospheric correction ignores higher order ionospheric errors such as the second and third order ionospheric terms in the refractive index formula and errors due to bending of the signal. The total electron content (TEC) is assumed to be same at two GPS frequencies. All these assumptions lead to erroneous estimations and corrections of the ionospheric errors. In this paper a rigorous treatment of these problems is presented. Different approximation formulas have been proposed to correct errors due to excess path length in addition to the free space path length, TEC difference at two GNSS frequencies, and third-order ionospheric term. The GPS dual-frequency residual range errors can be corrected within millimeter level accuracy using the proposed correction formulas.
Ptitsyna, N G; Kudrin, V A; Villorezi, D; Kopytenko, Iu A; Tiasto, M I; Kopytenko, E A; Bochko, V A; Iuchchi, N
1996-01-01
The study was inspired by earlier results that displayed influence of variable natural geomagnetic field (0.005-10 Hz range-ultra-low frequencies) on circulatory system, indicated possible correlation between industrial ultra-low frequency fields and prevalence of myocardial infarction. The authors conducted unique measurements of ultra-low frequency fields produced by electric engines. The results were compared with data on morbidity among railway transport workers. The findings are that level of magnetic variations in electric locomotive cabin can exceed 280 micro Tesla, whereas that in car sections reaches 50 micro Tesla. Occurrence of coronary heart disease among the locomotive operators appeared to be 2.0 + 0.2 times higher than that among the car section operators. Higher risk of coronary heart disease in the locomotive operators is associated with their increased occupational magnetic load.
Different fatigue-resistant leg muscles and EMG response during whole-body vibration.
Simsek, Deniz
2017-12-01
The purpose of this study was to determine the effects of static whole-body vibration (WBV) on the Electromyograhic (EMG) responses of leg muscles, which are fatigue-resistant in different manner. The study population was divided into two groups according to the values obtained by the Fatigue Index [Group I: Less Fatigue Resistant (LFR), n=11; Group II: More Fatigue Resistant (MFR), n=11]. The repeated electromyographic (EMG) activities of four leg muscles were analyzed the following determinants: (1) frequency (30 Hz, 35 Hz and 40 Hz); (2) stance position (static squat position); (3) amplitude (2 mm and 4 mm) and (4) knee flexion angle (120°), (5) vertical vibration platform. Vibration data were analyzed using Minitab 16 (Minitab Ltd, State College, PA, USA). The significance level was set at p<.05. The study results showed that static WBV stimuli given at different frequencies and amplitudes resulted in a significant increase (p<.05) in compared, the LFR group showed significantly (1) higher rates of quadriceps femoris and hamstring muscle fatigue (p<.05), (2) higher levels of knee extensor and flexor torque (p<.05) and (3) higher percentage increases in EMG activation at higher frequencies (max at 40 Hz) and amplitudes (4 mm) (p<.05). The present study can be used for the optimal prescription of vibration exercise and can serve to guide the development of training programs. Copyright © 2017 Elsevier Ltd. All rights reserved.
[Food quality and nutritional status in university students of eleven Chilean regions].
Ratner, Rinat G; Hernández, Paulina J; Martel, Jorge A; Atalah, Eduardo S
2012-12-01
The Chilean population has inadequate lifestyles and high prevalence of chronic diseases. To analyze eating behaviors, nutritional status and history of previous diseases, in students of higher education. Cross-sectional study in students of 54 higher education centers across the country. They answered a survey about dietary habits, physical activity, smoking, previous diseases and opinion of their nutritional condition. Weight and height were measured under standardized conditions and nutritional status classified according to body mass index. We studied 6,823 students aged 17 to 29 years. Forty seven percent did not have breakfast and 35% did not have lunch every day. A low proportion had a daily consumption of vegetables (51.2%), fruits (39.4%) and dairy products (57.5%). There was a high frequency of soft drinks, chips, cakes and sweets consumption. Seventy six percent were sedentary, 40.3% smokers and 27.4% overweight or obese. The latter had a significantly higher frequency of diabetes, hypertension and hypercholesterolemia. There was a poor agreement between actual nutritional status and self-perception, especially in males (Kappa index 0.38). Recipients of a food scholarship provided by the Ministry of Education ate lunch usually with a higher frequency (p < 0.05). A high prevalence of inadequate eating and physical activity patterns in these young subjects with good educational level was observed. The food scholarship has some positive effects, although differences in socioeconomic levels limited comparisons.
Analysis of sound pressure levels emitted by children's toys.
Sleifer, Pricila; Gonçalves, Maiara Santos; Tomasi, Marinês; Gomes, Erissandra
2013-06-01
To verify the levels of sound pressure emitted by non-certified children's toys. Cross-sectional study of sound toys available at popular retail stores of the so-called informal sector. Electronic, mechanical, and musical toys were analyzed. The measurement of each product was carried out by an acoustic engineer in an acoustically isolated booth, by a decibel meter. To obtain the sound parameters of intensity and frequency, the toys were set to produce sounds at a distance of 10 and 50cm from the researcher's ear. The intensity of sound pressure [dB(A)] and the frequency in hertz (Hz) were measured. 48 toys were evaluated. The mean sound pressure 10cm from the ear was 102±10 dB(A), and at 50cm, 94±8 dB(A), with p<0.05. The level of sound pressure emitted by the majority of toys was above 85dB(A). The frequency ranged from 413 to 6,635Hz, with 56.3% of toys emitting frequency higher than 2,000Hz. The majority of toys assessed in this research emitted a high level of sound pressure.
Requena, Pilar; Barrios, Diana; Robinson, Leanne J; Samol, Paula; Umbers, Alexandra J; Wangnapi, Regina; Ome-Kaius, Maria; Rosanas-Urgell, Anna; Mayor, Alfredo; López, Marta; de Lazzari, Elisa; Arévalo-Herrera, Myriam; Fernández-Becerra, Carmen; del Portillo, Hernando; Chitnis, Chetan E; Siba, Peter M; Rogerson, Stephen; Mueller, Ivo; Bardají, Azucena; Menéndez, Clara; Dobaño, Carlota
2015-04-01
Pregnancy triggers immunological changes aimed to tolerate the fetus. However, it has not been properly addressed whether similar changes occur in tropical areas with high infection pressure and whether these changes render women more susceptible to infectious diseases. We compared the frequencies of T cell subsets, including regulatory T cells, in pregnant and nonpregnant women from Papua New Guinea, a high malaria transmission area, and from Spain, a malaria-free country. We also assessed the relationship among these cellular subsets, malaria infection, and delivery outcomes. CD4(+)FOXP3(+)CD127(low) T cells (Tregs) were decreased in pregnant women in both countries but were not associated with malaria infection or poor delivery outcomes. An expansion of IFN-γ-producing cells and intracytoplasmic IFN-γ levels was found in pregnant compared with nonpregnant women only in Papua New Guinea. Increased CD4(+)IL-10(+)IFN-γ(+) frequencies and Treg-IFN-γ production were found in women with current Plasmodium falciparum infection. Higher CD4(+)IL-10(-)IFN-γ(+) T cells frequencies and production of proinflammatory cytokines (including TNF and IL-2) at recruitment (first antenatal visit) had a protective association with birth weight and future (delivery) P. falciparum infection, respectively. Higher intracellular IL-10 levels in T cells had a protective association with future P. falciparum infection and hemoglobin levels at delivery. The protective associations were found also with nonmalaria-specific T cell responses. Treg frequencies positively correlated with plasma eotaxin concentrations, but this subset did not express eotaxin receptor CCR3. Thus, an activated immune system during pregnancy might contribute to protection against malaria during pregnancy and poor delivery outcomes. Copyright © 2015 by The American Association of Immunologists, Inc.
Exploring the Use of Text and Instant Messaging in Higher Education Classrooms
ERIC Educational Resources Information Center
Lauricella, Sharon; Kay, Robin
2013-01-01
This article examined how higher education students used text and instant messaging for academic purposes with their peers and faculty. Specifically, comfort level, frequency of use, usefulness, reasons for messaging and differences between peer-to-peer and peer-to-instructor interactions were examined. Students noted that they were very…
Sukhodolsky, Denis G; Ruchkin, Vladislav V
2004-04-01
Examined the association of anger experience and two types of normative beliefs with physical aggression and nonaggressive antisocial behavior in 361 juvenile offenders and 206 high school students in Russia. All participants were male and ranged in age from 14 to 18 years. Higher frequency of aggressive acts was significantly associated with higher levels of anger and stronger beliefs that physical aggression is an appropriate course of action in conflicts. After statistically controlling for nonaggressive antisocial behavior, the relationship between physical aggression and antisocial beliefs was not significant. Similarly, with physical aggression controlled, nonaggressive antisocial behavior was uniquely associated with approval of deviancy, but not with anger or beliefs legitimizing aggression. Juvenile offenders reported higher levels of anger experience and higher frequency of aggression and antisocial behavior compared to high school students. There were no differences in normative beliefs between these two groups. This specificity of association of social-cognitive and emotion-regulation processes to aggressive and nonaggressive forms of antisocial behavior may be relevant to understanding the mechanisms of cognitive-behavioral therapy for conduct disorder and antisocial behavior.
Personality Traits Associated with Occupational "Burnout" in ABA Therapists
ERIC Educational Resources Information Center
Hurt, Amy A.; Grist, Cathy Lann; Malesky, Lann A., Jr.; McCord, David M.
2013-01-01
Background: Applied behaviour analysis (ABA) therapists typically work one-to-one with children with autism for extended periods of time, which often leads to high levels of job-related stress, lower levels of job satisfaction, increased frequency of occupational "burnout" and higher than average job turnover (Journal of Autism…
Correlates of overweight status in Chinese youth: an East-West paradox.
Hsu, Ya-Wen; Johnson, C Anderson; Chou, Chih-Ping; Unger, Jennifer B; Sun, Ping; Xie, Bin; Palmer, Paula H; Gallaher, Peggy E; Spruijt-Metz, Donna
2011-07-01
To examine the odds of overweight and related correlates in Chinese adolescents. Cross-sectional study in 9023 adolescents. Chinese youth were more likely to be overweight if they spent more time being sedentary; slept <7 hours/night; were male; were younger; participated more in vigorous physical activity; and had higher levels of parental education, a higher frequency of vegetable intake, and a lower frequency of sweet/fast food intake. Overweight-related correlates seem to play different roles in the Chinese culture than in Western cultures. This may be due to culture-specific perceptions and changes in lifestyle accompanying socioeconomic transitions.
Notched-noise precursors improve detection of low-frequency amplitude modulationa)
Almishaal, Ali; Bidelman, Gavin M.; Jennings, Skyler G.
2017-01-01
Amplitude modulation (AM) detection was measured with a short (50 ms), high-frequency carrier as a function of carrier level (Experiment I) and modulation frequency (Experiment II) for conditions with or without a notched-noise precursor. A longer carrier (500 ms) was also included in Experiment I. When the carrier was preceded by silence (no precursor condition) AM detection thresholds worsened for moderate-level carriers compared to lower- or higher-level carriers, resulting in a “mid-level hump.” AM detection thresholds with a precursor were better than those without a precursor, primarily for moderate-to-high level carriers, thus eliminating the mid-level hump in AM detection. When the carrier was 500 ms, AM thresholds improved by a constant (across all levels) relative to AM thresholds with a precursor, consistent with the longer carrier providing more “looks” to detect the AM signal. Experiment II revealed that improved AM detection with compared to without a precursor is limited to low-modulation frequencies (<60 Hz). These results are consistent with (1) a reduction in cochlear gain over the course of the precursor perhaps via the medial olivocochlear reflex or (2) a form of perceptual enhancement which may be mediated by adaptation of inhibition. PMID:28147582
Cigarette smoking causes hearing impairment among Bangladeshi population.
Sumit, Ahmed Faisal; Das, Anindya; Sharmin, Zinat; Ahsan, Nazmul; Ohgami, Nobutaka; Kato, Masashi; Akhand, Anwarul Azim
2015-01-01
Lifestyle including smoking, noise exposure with MP3 player and drinking alcohol are considered as risk factors for affecting hearing synergistically. However, little is known about the association of cigarette smoking with hearing impairment among subjects who carry a lifestyle without using MP3 player and drinking alcohol. We showed here the influence of smoking on hearing among Bangladeshi subjects who maintain a lifestyle devoid of using MP3 player and drinking alcohol. A total of 184 subjects (smokers: 90; non-smokers: 94) were included considering their duration and frequency of smoking for conducting this study. The mean hearing thresholds of non-smoker subjects at 1, 4, 8 and 12 kHz frequencies were 5.63 ± 2.10, 8.56±5.75, 21.06 ± 11.06, 40.79 ± 20.36 decibel (dB), respectively and that of the smokers were 7 ± 3.8, 13.27 ± 8.4, 30.66 ± 12.50 and 56.88 ± 21.58 dB, respectively. The hearing thresholds of the smokers at 4, 8 and 12 kHz frequencies were significantly (p<0.05) higher than those of the non-smokers, while no significant differences were observed at 1 kHz frequency. We also observed no significant difference in auditory thresholds among smoker subgroups based on smoking frequency. In contrast, subjects smoked for longer duration (>5 years) showed higher level of auditory threshold (62.16 ± 19.87 dB) at 12 kHz frequency compared with that (41.52 ± 19.21 dB) of the subjects smoked for 1-5 years and the difference in auditory thresholds was statistically significant (p<0.0002). In this study, the Brinkman Index (BI) of smokers was from 6 to 440 and the adjusted odds ratio showed a positive correlation between hearing loss and smoking when adjusted for age and body mass index (BMI). In addition, age, but not BMI, also played positive role on hearing impairment at all frequencies. Thus, these findings suggested that cigarette smoking affects hearing level at all the frequencies tested but most significantly at extra higher frequencies.
Cigarette Smoking Causes Hearing Impairment among Bangladeshi Population
Sumit, Ahmed Faisal; Das, Anindya; Sharmin, Zinat; Ahsan, Nazmul; Ohgami, Nobutaka; Kato, Masashi; Akhand, Anwarul Azim
2015-01-01
Lifestyle including smoking, noise exposure with MP3 player and drinking alcohol are considered as risk factors for affecting hearing synergistically. However, little is known about the association of cigarette smoking with hearing impairment among subjects who carry a lifestyle without using MP3 player and drinking alcohol. We showed here the influence of smoking on hearing among Bangladeshi subjects who maintain a lifestyle devoid of using MP3 player and drinking alcohol. A total of 184 subjects (smokers: 90; non-smokers: 94) were included considering their duration and frequency of smoking for conducting this study. The mean hearing thresholds of non-smoker subjects at 1, 4, 8 and 12 kHz frequencies were 5.63±2.10, 8.56±5.75, 21.06±11.06, 40.79±20.36 decibel (dB), respectively and that of the smokers were 7±3.8, 13.27±8.4, 30.66±12.50 and 56.88±21.58 dB, respectively. The hearing thresholds of the smokers at 4, 8 and 12 kHz frequencies were significantly (p<0.05) higher than those of the non-smokers, while no significant differences were observed at 1 kHz frequency. We also observed no significant difference in auditory thresholds among smoker subgroups based on smoking frequency. In contrast, subjects smoked for longer duration (>5 years) showed higher level of auditory threshold (62.16±19.87 dB) at 12 kHz frequency compared with that (41.52±19.21 dB) of the subjects smoked for 1-5 years and the difference in auditory thresholds was statistically significant (p<0.0002). In this study, the Brinkman Index (BI) of smokers was from 6 to 440 and the adjusted odds ratio showed a positive correlation between hearing loss and smoking when adjusted for age and body mass index (BMI). In addition, age, but not BMI, also played positive role on hearing impairment at all frequencies. Thus, these findings suggested that cigarette smoking affects hearing level at all the frequencies tested but most significantly at extra higher frequencies. PMID:25781179
Garadah, Taysir S; Jaradat, Ahmed A; AlAlawi, Mohammed E; Hassan, Adla B; Sequeira, Reginald P
2016-01-01
Background Inflammatory markers are increased during vaso-occlusive crisis (VOC) in adult patients with sickle cell anemia (SCA), but this is not clear in clinical steady state. Aim The present study aims to establish the frequency and intensity of bone pain episodes in adult patients with SCA in clinical steady state and to determine the correlation between different inflammatory markers, other variables including QT dispersion (QTd) and pain frequency and intensity in SCA. Patients and methods Patients were classified into two groups: group 1, those with more than three hospital admissions in the last 6 months, and group 2, those with no hospital admission. Pearson correlation between variables such as body mass index (BMI), level of tumor necrosis factor (TNF-α), interleukin-1 (IL-1), C-reactive protein (CRP), hemoglobin (Hb), reticulocyte count, white blood cell count (WBC), ferritin, lactate dehydrogenase (LDH), parathormone (PTH), vitamin D3 (25-OH cholecalciferol) and bone pain frequency with severity was evaluated. Results Forty-six patients were enrolled in this study with a mean age of 18.47±5.78 years, with 23 patients in each group. Vitamin D3 and Hb were lower (17.04±5.77 vs 37.59±4.83 ng/L, P<0.01 and 7.96±0.3 vs 8.44±0.27 g/dL, P<0.01, respectively); the inflammatory markers showed significantly higher level of TNF-α, IL-1 and CRP (56.52±5.43 pg/ml, 44.17±4.54 pg/ml and 3.20±0.72 mg/L, respectively, P<0.05); WBC, LDH and reticulocyte count were also significantly higher and the QTd was higher (45.0±2.22 vs 41.55±0.8 ms, P<0.05) in group 1 when compared with group 2. Pearson correlation coefficient showed significant positive correlation between serum level of TNF-α and bone pain frequency (r=0.414, P<0.005) and serum level of IL-1 (r=0.39, P<0.008). Conclusion There is a strong positive correlation between TNF-α, IL-1 and WBC and bone pain frequency in steady state in adult patients with SCA. CRP and low hemoglobin had weak positive correlation. QTd was significantly longer in patients who had hospitalizations with VOC. PMID:27843377
Recent performance of and plasma outage studies with the SNS H{sup −} source
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stockli, M. P., E-mail: stockli@ornl.gov; Han, B.; Murray, S. N.
2016-02-15
Spallation Neutron Source ramps to higher power levels that can be sustained with high availability. The goal is 1.4 MW despite a compromised radio frequency quadrupole (RFQ), which requires higher radio frequency power than design levels to approach the nominal beam transmission. Unfortunately at higher power the RFQ often loses its thermal stability, a problem apparently enhanced by beam losses and high influxes of hydrogen. Delivering as much H{sup −} beam as possible with the least amount of hydrogen led to plasma outages. The root cause is the dense 1-ms long ∼55-kW 2-MHz plasma pulses reflecting ∼90% of the continuousmore » ∼300 W, 13-MHz power, which was mitigated with a 4-ms filter for the reflected power signal and an outage resistant, slightly detuned 13-MHz match. Lowering the H{sub 2} gas also increased the H{sup −} beam current to ∼55 mA and increased the RFQ transmission by ∼7% (relative)« less
Modulation of microsaccades by spatial frequency during object categorization.
Craddock, Matt; Oppermann, Frank; Müller, Matthias M; Martinovic, Jasna
2017-01-01
The organization of visual processing into a coarse-to-fine information processing based on the spatial frequency properties of the input forms an important facet of the object recognition process. During visual object categorization tasks, microsaccades occur frequently. One potential functional role of these eye movements is to resolve high spatial frequency information. To assess this hypothesis, we examined the rate, amplitude and speed of microsaccades in an object categorization task in which participants viewed object and non-object images and classified them as showing either natural objects, man-made objects or non-objects. Images were presented unfiltered (broadband; BB) or filtered to contain only low (LSF) or high spatial frequency (HSF) information. This allowed us to examine whether microsaccades were modulated independently by the presence of a high-level feature - the presence of an object - and by low-level stimulus characteristics - spatial frequency. We found a bimodal distribution of saccades based on their amplitude, with a split between smaller and larger microsaccades at 0.4° of visual angle. The rate of larger saccades (⩾0.4°) was higher for objects than non-objects, and higher for objects with high spatial frequency content (HSF and BB objects) than for LSF objects. No effects were observed for smaller microsaccades (<0.4°). This is consistent with a role for larger microsaccades in resolving HSF information for object identification, and previous evidence that more microsaccades are directed towards informative image regions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Postautotomy tail activity in the Balearic lizard, Podarcis lilfordi
NASA Astrophysics Data System (ADS)
Pafilis, Panayiotis; Pérez-Mellado, Valentín; Valakos, Efstratios
2008-03-01
Caudal autotomy is an effective antipredator strategy widespread among lizards. The shed tail thrashes vigorously for long periods to distract the predator and facilitate the lizard’s escape. This movement is maintained by energy supplied by the anaerobic conversion of glycogen into lactate. It has been suggested that lactate accumulation serves as an index for the vigor of tail thrashing. We made three predictions: (1) tail loss frequency should be higher under heavier predation regime, (2) the duration of postautotomy tail movement should be extended in populations under heavy predation pressure as an adaptation to the higher risk and the increased need for defense, and (3) as result, lactate in these tail tissues should be concentrated at higher levels. To eliminate the impact of phylogeny and environmental factors on the interpretation of our result, we focused exclusively on one species, the Balearic lizard ( Podarcis lilfordi). We studied three populations under different predation pressure but sharing the same climatic conditions. We found no differences among the studied populations either in postautotomy duration of tail movement or in levels of final lactate accumulation while autotomy frequency was higher where predation pressure was more intense. Τail loss effectiveness is directly influenced by the level of predation, while secondary features of the trait appear to remain independent from the impact of environment.
Roles of safety climate and shift work on perceived injury risk: a multi-level analysis.
Huang, Yueng-Hsiang; Chen, Jiu-Chiuan; DeArmond, Sarah; Cigularov, Konstantin; Chen, Peter Y
2007-11-01
This study evaluated the relationship between employees' work shift (i.e., day shift versus night shift) and perceptions of injury risk, and how the relationship is affected by company level safety climate and injury frequency. The results showed that night shift workers perceived a higher level of injury risk compared to day shift workers. Both company level safety climate and injury frequency played critical roles in predicting individual perceived work injury risk. Perception of injury risk of night shift workers was significantly lower when they perceived high-level rather than low-level safety climate. However, this pattern was not noticeable for day shift workers. These findings highlighted the importance of considering company level factors when attempting to understand the differences between day shift and night shift work on an individual's perception of injury risk.
[Factors Associated with the Use of Protective Gear among Adults during Recreational Sledging].
Ruedl, G; Pocecco, E; Kopp, M; Raas, C; Blauth, M; Brucker, P U; Burtscher, M
2015-09-01
Recreational sledging (tobogganing) is a very popular winter sport in the Alps. Therefore, injury prevention through the usage of protective gear seems important. Therefore, the aim of this study was to evaluate factors associated with the use of protective gear among adults during recreational sledging. Adult recreational sledgers were interviewed during the winter seasons 2012/13 and 2013/14 at six sledging tracks in Austria on demographics, skill level, sledging frequency, risk taking behaviour, sitting alone or with another person on the sledge, previous sledging-related injuries, and use of protective gear, respectively. Interviews were conducted on all days of the week. A total of 1968 adult sledgers (49.4 % females) with a mean age of 37.1 ± 14.4 years participated in this study. A (ski) helmet, sun or snow goggles, a back protector, and wrist guards were used by 42.3 %, 71.0 %, 5.9 %, 2.6 % of sledgers, respectively. Helmet use was significantly higher with increasing age and increasing skill level as well as when sitting alone compared to sitting together with another person. Females, Austrians, persons sitting alone on the sledge, a higher frequency of sledging and a higher skill level were significantly associated with an increasing use of goggles. A back protector was significantly more often worn by younger people, more risky sledgers, and persons with a previous sledging-related injury. Wrist guards were significantly more often used by persons with a previous sledging-related injury. During recreational sledging, the factors age, sex, nationality, skill level, sitting alone compared to sitting together with another person on the sledge, sledging frequency, and injury experience were associated with the frequencies of usage of different types of protective gear. These factors should be considered when implementing preventive measures for recreational sledging. © Georg Thieme Verlag KG Stuttgart · New York.
Accompanying migrainous features in pediatric migraine patients with restless legs syndrome.
Sevindik, Melis Sohtaoğlu; Demirci, Seden; Göksan, Baki; Özge, Aynur; Savrun, Feray Karaali; Onur, Hatice; Yıldırım, Veli; Simsek, Ismail; Ozhan, Harika; Uludüz, Derya
2017-09-01
The present study aimed to examine the frequency of restless legs syndrome (RLS) in pediatric patients with migraine and tension-type headache (TTH) and to investigate accompanying migrainous symptoms, sleep characteristics, as well as levels of serum ferritin between the pediatric migraine patients with RLS and those without RLS. We included 65 consecutive patients diagnosed with migraine, 20 patients with TTH, and 97 headache-free children in our study. Demographic, clinical, and laboratory data were noted. The presence of a primary headache was diagnosed using the ICHD-II criteria, and RLS was determined with face-to-face interviews conducted by an experienced neurologist based on the revised International RLS Study Group criteria for pediatrics. The frequency of RLS in pediatric migraine and TTH patients was significantly higher than in the controls (p = 0.0001 and p = 0.025, respectively). The frequencies of allodynia, vertigo/dizziness, and self-reported frequent arousals were significantly higher, and serum ferritin levels were significantly lower in migraine patients with RLS compared to those without RLS (p = 0.05, p = 0.028, p = 0.02, and p = 0.038, respectively). Our study suggests that the frequency of RLS is higher in pediatric migraine and TTH patients compared to controls. Therefore, pediatric headache patients should be questioned about the presence of RLS, as this co-occurrence may lead to more frequent accompanying migrainous symptoms and sleep disturbances.
Bell, Wade E; Hallworth, Richard; Wyatt, Todd A; Sisson, Joseph H
2015-01-01
When Paramecium encounters positive stimuli, the membrane hyperpolarizes and ciliary beat frequency increases. We adapted an established immobilization protocol using a biological adhesive and a novel digital analysis system to quantify beat frequency in immobilized Paramecium. Cells showed low mortality and demonstrated beat frequencies consistent with previous studies. Chemoattractant molecules, reduction in external potassium, and posterior stimulation all increased somatic beat frequency. In all cases, the oral groove cilia maintained a higher beat frequency than mid-body cilia, but only oral cilia from cells stimulated with chemoattactants showed an increase from basal levels. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.
Misawa, Kyohei; Yasuda, Hajime; Araki, Marito; Ochiai, Tomonori; Morishita, Soji; Shirane, Shuichi; Edahiro, Yoko; Gotoh, Akihiko; Ohsaka, Akimichi; Komatsu, Norio
2018-06-01
The majority of patients with Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) harbor JAK2, CALR, or MPL mutations. We compared clinical manifestations of different subtypes of JAK2 and CALR mutations in Japanese patients with MPNs. Within our cohort, we diagnosed 166 patients as polycythemia vera (PV), 212 patients as essential thrombocythemia (ET), 23 patients as pre-primary myelofibrosis (PMF), 65 patients as overt PMF, and 27 patients as secondary myelofibrosis following the 2016 WHO criteria. Compared to patients with JAK2V617F-mutated PV, JAK2 exon 12-mutated PV patients were younger, showed lower white blood cell (WBC) counts, lower platelet counts, higher red blood cell counts, and higher frequency of thrombotic events. Compared to JAK2-mutated ET patients, CALR-mutated ET patients were younger, showed lower WBC counts, lower hemoglobin levels, higher platelet counts, and fewer thrombotic events. CALR type 1-like mutation was the dominant subtype in CALR-mutated overt PMF patients. Compared with JAK2V617F-mutated ET patients, JAK2V617F-mutated pre-PMF patients showed higher LDH levels, lower hemoglobin levels, higher JAK2V617F allele burden, and higher frequency of splenomegaly. In conclusion, Japanese patients with MPNs grouped by different mutation subtypes exhibit characteristics similar to those of their Western counterparts. In addition, ET and pre-PMF patients show different characteristics, even when restricted to JAK2V617F-mutated patients.
Factors Associated with Depressive Symptoms among Filipino University Students
Lee, Romeo B.; Maria, Madelene Sta.; Estanislao, Susana; Rodriguez, Cristina
2013-01-01
Depression can be prevented if its symptoms are addressed early and effectively. Prevention against depression among university students is rare in the Philippines, but is urgent because of the rising rates of suicide among the group. Evidence is needed to systematically identify and assist students with higher levels of depressive symptoms. We carried out a survey to determine the social and demographic factors associated with higher levels of depressive symptoms among 2,436 Filipino university students. The University Students Depression Inventory with measures on lethargy, cognition-emotion, and academic motivation, was used. Six of the 11 factors analyzed were found to be statistically significantly associated with more intense levels of depressive symptoms. These factors were: frequency of smoking, frequency of drinking, not living with biological parents, dissatisfaction with one’s financial condition, level of closeness with parents, and level of closeness with peers. Sex, age category, course category, year level and religion were not significantly related. In identifying students with greater risk for depression, characteristics related to lifestyle, financial condition, parents and peers are crucial. There is a need to carry out more surveys to develop the pool of local knowledge on student depression. PMID:24223198
So, Wi-Young
2013-01-01
The purpose of this study was to examine whether the frequency of breakfast consumption was related to academic performance in healthy Korean adolescents. We analyzed data from the seventh Korea Youth Risk Behavior Web-based Survey conducted in 2011, in which 75,643 adolescents from school grades 7-12 participated. We assessed the association between the frequency of breakfast consumption (per week) and academic performance using multivariate logistic regression analysis after adjusting for covariates such as age, body mass index, frequency of smoking, frequency of drinking, parents' education level, family economic status, frequency of vigorous physical activity (PA), frequency of moderate PA, frequency of muscular strength exercises, and level of mental stress. For male adolescents, the odds ratios (ORs) for achieving average or higher academic performance according to the breakfast frequency per week were once per week, 1.004 (P=0.945); twice per week, 0.915 (P=0.153); 3 days per week, 0.928 (P=0.237); 4 days per week, 1.087 (P=0.176); 5 days per week, 1.258 (P<0.001); 6 days per week, 1.473 (P<0.001); and every day, 1.700 (P<0.001), compared to no breakfast per week. For female adolescents, the ORs for achieving average or higher academic performance according to the breakfast frequency were once per week, 1.068 (P=0.320); twice per week, 1.140 (P=0.031); 3 days per week, 1.179 (P=0.004); 4 days per week, 1.339 (P<0.001); 5 days per week, 1.449 (P<0.001); 6 days per week, 1.768 (P<0.001); and every day, 1.922 (P<0.001), compared to no breakfast per week. The frequency of breakfast consumption is positively correlated with academic performance in both male and female healthy adolescents in Korea.
Association of Spicy Food Consumption Frequency with Serum Lipid Profiles in Older People in China.
Yu, K; Xue, Y; He, T; Guan, L; Zhao, A; Zhang, Y
2018-01-01
There has been recent interest in spicy foods and their bioactive ingredients for cardiovascular health. This study aims to explore relationship between spicy food consumption frequency and serum lipid profiles in a cross-sectional sample of older Chinese from China Health and Nutrition Survey (CHNS). A total of 1549 participant aged 65 years and above from CHNS 2009 were included in the analysis. Information on spicy food consumption was obtained using a questionnaire survey and 24h dietary recalls over three consecutive days combined with weighted food inventory. Fasting blood samples were analyzed for total cholesterol (TC), triglycerides, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (apoA1) and apolipoprotein B (apoB). Correlations between spicy food consumption frequency and serum lipid profiles were evaluated by multivariate linear regression models. The result shows a significant positive association between frequency of spicy food consumption estimated by the frequency question and daily spicy food intake calculated from 24h recall. After adjustment for potential lifestyle and dietary confounding factors, men with higher frequency of spicy food consumption showed higher apoA1 level, and lower ratio of LDL-C/apoB (p for trend <0.05). For female, frequency of spicy food consumption was significantly associated with TC, LDL-C, apoB, LDL-C/HDL-C, and apoB/apoA1 in an inverse manner, and positively correlated with apoA1 level (p for trend <0.05). In this study with Chinese aged 65y and above, increased spicy food consumption frequency may favorably associated with some risk factors for cardiovascular diseases.
Soul and Musical Theater: A Comparison of Two Vocal Styles.
Hallqvist, Hanna; Lã, Filipa M B; Sundberg, Johan
2017-03-01
The phonatory and resonatory characteristics of nonclassical styles of singing have been rarely analyzed in voice research. Six professional singers volunteered to sing excerpts from two songs pertaining to the musical theater and to the soul styles of singing. Voice source parameters and formant frequencies were analyzed by inverse filtering tones, sung at the same fundamental frequencies in both excerpts. As compared with musical theater, the soul style was characterized by significantly higher subglottal pressure and maximum flow declination rate. Yet sound pressure level was lower, suggesting higher glottal resistance. The differences would be the effects of firmer glottal adduction and a greater frequency separation between the first formant and its closest spectrum partial in soul than in musical theater. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
McMillan, Garnett P; Hanson, Tim; Bedrick, Edward J; Lapham, Sandra C
2005-09-01
This study demonstrates the usefulness of the Bivariate Dale Model (BDM) as a method for estimating the relationship between risk factors and the quantity and frequency of alcohol use, as well as the degree of association between these highly correlated drinking measures. The BDM is used to evaluate childhood sexual abuse, along with age and gender, as risk factors for the quantity and frequency of beer consumption in a sample of driving-while-intoxicated (DWI) offenders (N = 1,964; 1,612 men). The BDM allows one to estimate the relative odds of drinking up to each level of ordinal-scaled quantity and frequency of alcohol use, as well as model the degree of association between quantity and frequency of alcohol consumption as a function of covariates. Individuals who experienced childhood sexual abuse have increased risks of higher quantity and frequency of beer consumption. History of childhood sexual abuse has a greater effect on women, causing them to drink higher quantities of beer per drinking occasion. The BDM is a useful method for evaluating predictors of the quantity-frequency of alcohol consumption. SAS macrocode for fitting the BDM model is provided.
Intimate Partner Violence, Police Involvement, and Women's Trauma Symptoms.
Rancher, Caitlin; Jouriles, Ernest N; McDonald, Renee
2018-06-01
This study examined whether police involvement in intimate partner violence (IPV) incidents is associated with women's trauma symptoms. Participants were 95 women recruited from domestic violence shelters. Women reported on their trauma symptoms, the frequency of IPV victimization, the use of a weapon during IPV, and police involvement over the year following shelter departure. Police involvement in IPV was associated with higher levels of reexperiencing trauma symptoms 1 year after shelter departure, even after controlling for baseline trauma symptoms, the frequency of IPV, and the use of a weapon during IPV. Women's race and ethnicity did not moderate the results. These findings suggest police involvement in IPV incidents may be associated with higher levels of trauma symptoms experienced by women. Further investigation into law enforcement practices and policies to help reduce women's distress is needed.
Amplification of flood frequencies with local sea level rise and emerging flood regimes
NASA Astrophysics Data System (ADS)
Buchanan, Maya K.; Oppenheimer, Michael; Kopp, Robert E.
2017-06-01
The amplification of flood frequencies by sea level rise (SLR) is expected to become one of the most economically damaging impacts of climate change for many coastal locations. Understanding the magnitude and pattern by which the frequency of current flood levels increase is important for developing more resilient coastal settlements, particularly since flood risk management (e.g. infrastructure, insurance, communications) is often tied to estimates of flood return periods. The Intergovernmental Panel on Climate Change’s Fifth Assessment Report characterized the multiplication factor by which the frequency of flooding of a given height increases (referred to here as an amplification factor; AF). However, this characterization neither rigorously considered uncertainty in SLR nor distinguished between the amplification of different flooding levels (such as the 10% versus 0.2% annual chance floods); therefore, it may be seriously misleading. Because both historical flood frequency and projected SLR are uncertain, we combine joint probability distributions of the two to calculate AFs and their uncertainties over time. Under probabilistic relative sea level projections, while maintaining storm frequency fixed, we estimate a median 40-fold increase (ranging from 1- to 1314-fold) in the expected annual number of local 100-year floods for tide-gauge locations along the contiguous US coastline by 2050. While some places can expect disproportionate amplification of higher frequency events and thus primarily a greater number of historically precedented floods, others face amplification of lower frequency events and thus a particularly fast growing risk of historically unprecedented flooding. For example, with 50 cm of SLR, the 10%, 1%, and 0.2% annual chance floods are expected respectively to recur 108, 335, and 814 times as often in Seattle, but 148, 16, and 4 times as often in Charleston, SC.
Preferred listening levels of mobile phone programs when considering subway interior noise
Yu, Jyaehyoung; Lee, Donguk; Han, Woojae
2016-01-01
Today, people listen to music loud using personal listening devices. Although a majority of studies have reported that the high volume played on these listening devices produces a latent risk of hearing problems, there is a lack of studies on “double noise exposures” such as environmental noise plus recreational noise. The present study measures the preferred listening levels of a mobile phone program with subway interior noise for 74 normal-hearing participants in five age groups (ranging from 20s to 60s). The speakers presented the subway interior noise at 73.45 dB, while each subject listened to three application programs [Digital Multimedia Broadcasting (DMB), music, game] for 30 min using a tablet personal computer with an earphone. The participants’ earphone volume levels were analyzed using a sound level meter and a 2cc coupler. Overall, the results showed that those in their 20s listened to the three programs significantly louder with DMB set at significantly higher volume levels than for the other programs. Higher volume levels were needed for middle frequency compared to the lower and higher frequencies. We concluded that any potential risk of noise-induced hearing loss for mobile phone users should be communicated when users listen regularly, although the volume level was not high enough that the users felt uncomfortable. When considering individual listening habits on mobile phones, further study to predict total accumulated environmental noise is still needed. PMID:26780960
Preferred listening levels of mobile phone programs when considering subway interior noise.
Yu, Jyaehyoung; Lee, Donguk; Han, Woojae
2016-01-01
Today, people listen to music loud using personal listening devices. Although a majority of studies have reported that the high volume played on these listening devices produces a latent risk of hearing problems, there is a lack of studies on "double noise exposures" such as environmental noise plus recreational noise. The present study measures the preferred listening levels of a mobile phone program with subway interior noise for 74 normal-hearing participants in five age groups (ranging from 20s to 60s). The speakers presented the subway interior noise at 73.45 dB, while each subject listened to three application programs [Digital Multimedia Broadcasting (DMB), music, game] for 30 min using a tablet personal computer with an earphone. The participants' earphone volume levels were analyzed using a sound level meter and a 2cc coupler. Overall, the results showed that those in their 20s listened to the three programs significantly louder with DMB set at significantly higher volume levels than for the other programs. Higher volume levels were needed for middle frequency compared to the lower and higher frequencies. We concluded that any potential risk of noise-induced hearing loss for mobile phone users should be communicated when users listen regularly, although the volume level was not high enough that the users felt uncomfortable. When considering individual listening habits on mobile phones, further study to predict total accumulated environmental noise is still needed.
Szabo Portela, Annika; Granqvist, Svante; Ternström, Sten; Södersten, Maria
2018-01-01
This study aimed to assess vocal behavior in women with voice-intensive occupations to investigate differences between patients and controls and between work and leisure conditions with environmental noise level as an experimental factor. Patients with work-related voice disorders, 10 with phonasthenia and 10 with vocal nodules, were matched regarding age, profession, and workplace with 20 vocally healthy colleagues. The sound pressure level of environmental noise and the speakers' voice, fundamental frequency, and phonation ratio were registered from morning to night during 1 week with a voice accumulator. Voice data were assessed in low (≤55 dBA), moderate, and high (>70 dBA) environmental noise levels. The average environmental noise level was significantly higher during the work condition for patients with vocal nodules (73.9 dBA) and their controls (73.0 dBA) compared with patients with phonasthenia (68.3 dBA) and their controls (67.1 dBA). The average voice level and the fundamental frequency were also significantly higher during work for the patients with vocal nodules and their controls. During the leisure condition, there were no significant differences in average noise and voice level nor fundamental frequency between the groups. The patients with vocal nodules and their controls spent significantly more time and used their voices significantly more in high-environmental noise levels. High noise levels during work and demands from the occupation impact vocal behavior. Thus, assessment of voice ergonomics should be part of the work environmental management. To reduce environmental noise levels is important to improve voice ergonomic conditions in communication-intensive and vocally demanding workplaces. Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
Boles, Richard E; Burdell, Alexandra; Johnson, Susan L; Gavin, William J; Davies, Patricia L; Bellows, Laura L
2014-09-01
The purpose of this study was to refine and psychometrically test an instrument measuring the home food and activity environment of geographically and economically diverse families of preschool aged children. Caregivers of preschool aged children (n = 83) completed a modified self-report questionnaire. Reliably trained researchers conducted independent observations on 25 randomly selected homes. Agreement statistics were conducted at the item level (154 total items) to determine reliability. Frequency counts were calculated to identify item availability. Results showed Kappa statistics were high (.67-1.00) between independent researchers but varied between researchers and parents resulting in 85 items achieving criterion validity (Kappa >.60). Analyses of reliable items revealed the presence in the home of a high frequency of unhealthy snack foods, high fat milk and low frequency of availability of fruits/vegetables and low fat milk. Fifty-two percent of the homes were arranged with a television in the preschool child's bedroom. Physical Activity devices also were found to have high frequency availability. Families reporting lower education reported higher levels of sugar sweetened beverages and less low-fat dairy (p < .05) compared with higher education families. Low-income families (<$27K per year) reported significantly fewer Physical Activity devices (p < .001) compared with higher income families. Hispanic families reported significantly higher numbers of Sedentary Devices (p < .05) compared with non-Hispanic families. There were no significant differences between demographic comparisons on available fruits/vegetables, meats, whole grains, and regular fat dairy. A modified home food and activity instrument was found to reliably identify foods and activity devices with geographically and economically diverse families. Copyright © 2014 Elsevier Ltd. All rights reserved.
Associations between CD36 gene polymorphisms and susceptibility to coronary artery heart disease
Zhang, Y.; Ling, Z.Y.; Deng, S.B.; Du, H.A.; Yin, Y.H.; Yuan, J.; She, Q.; Chen, Y.Q.
2014-01-01
Associations between polymorphisms of the CD36 gene and susceptibility to coronary artery heart disease (CHD) are not clear. We assessed allele frequencies and genotype distributions of CD36 gene polymorphisms in 112 CHD patients and 129 control patients using semi-quantitative polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis. Additionally, we detected CD36 mRNA expression by real-time quantitative PCR, and we quantified plasma levels of oxidized low-density lipoprotein (ox-LDL) using an enzyme-linked immunosorbent assay (ELISA). There were no significant differences between the two groups (P>0.05) in allele frequencies of rs1761667 or in genotype distribution and allele frequencies of rs3173798. The genotype distribution of rs1761667 significantly differed between CHD patients and controls (P=0.034), with a significantly higher frequency of the AG genotype in the CHD group compared to the control group (P=0.011). The plasma levels of ox-LDL in patients with the AG genotype were remarkably higher than those with the GG and AA genotypes (P=0.010). In a randomized sample taken from patients in the two groups, the CD36 mRNA expression of the CHD patients was higher than that of the controls. In CHD patients, the CD36 mRNA expression in AG genotype patients was remarkably higher than in those with an AA genotype (P=0.005). After adjusted logistic regression analysis, the AG genotype of rs1761667 was associated with an increased risk of CHD (OR=2.337, 95% CI=1.336-4.087, P=0.003). In conclusion, the rs1761667 polymorphism may be closely associated with developing CHD in the Chongqing Han population of China, and an AG genotype may be a genetic susceptibility factor for CHD. PMID:25118627
Sulaiman, A H; Seluakumaran, K; Husain, R
2013-08-01
To investigate listening habits and hearing risks associated with the use of personal listening devices among urban high school students in Malaysia. Cross-sectional, descriptive study. In total, 177 personal listening device users (13-16 years old) were interviewed to elicit their listening habits (e.g. listening duration, volume setting) and symptoms of hearing loss. Their listening levels were also determined by asking them to set their usual listening volume on an Apple iPod TM playing a pre-selected song. The iPod's sound output was measured with an artificial ear connected to a sound level meter. Subjects also underwent pure tone audiometry to ascertain their hearing thresholds at standard frequencies (0.5-8 kHz) and extended high frequencies (9-16 kHz). The mean measured listening level and listening duration for all subjects were 72.2 dBA and 1.2 h/day, respectively. Their self-reported listening levels were highly correlated with the measured levels (P < 0.001). Subjects who listened at higher volumes also tend to listen for longer durations (P = 0.012). Male subjects listened at a significantly higher volume than female subjects (P = 0.008). When sound exposure levels were compared with the recommended occupational noise exposure limit, 4.5% of subjects were found to be listening at levels which require mandatory hearing protection in the occupational setting. Hearing loss (≥25 dB hearing level at one or more standard test frequencies) was detected in 7.3% of subjects. Subjects' sound exposure levels from the devices were positively correlated with their hearing thresholds at two of the extended high frequencies (11.2 and 14 kHz), which could indicate an early stage of noise-induced hearing loss. Although the average high school student listened at safe levels, a small percentage of listeners were exposed to harmful sound levels. Preventive measures are needed to avoid permanent hearing damage in high-risk listeners. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Fraser, Matthew; McKay, Colette M.
2012-01-01
Temporal modulation transfer functions (TMTFs) were measured for six users of cochlear implants, using different carrier rates and levels. Unlike most previous studies investigating modulation detection, the experimental design limited potential effects of overall loudness cues. Psychometric functions (percent correct discrimination of modulated from unmodulated stimuli versus modulation depth) were obtained. For each modulation depth, each modulated stimulus was loudness balanced to the unmodulated reference stimulus, and level jitter was applied in the discrimination task. The loudness-balance data showed that the modulated stimuli were louder than the unmodulated reference stimuli with the same average current, thus confirming the need to limit loudness cues when measuring modulation detection. TMTFs measured in this way had a low-pass characteristic, with a cut-off frequency (at comfortably loud levels) similar to that for normal-hearing listeners. A reduction in level caused degradation in modulation detection efficiency and a lower-cut-off frequency (i.e. poorer temporal resolution). An increase in carrier rate also led to a degradation in modulation detection efficiency, but only at lower levels or higher modulation frequencies. When detection thresholds were expressed as a proportion of dynamic range, there was no effect of carrier rate for the lowest modulation frequency (50 Hz) at either level. PMID:22146425
Panico, James; Healey, E Charles
2009-04-01
To determine how text type, topic familiarity, and stuttering frequency influence listener recall, comprehension, and perceived mental effort. Sixty adults listened to familiar and unfamiliar narrative and expository texts produced with 0%, 5%, 10%, and 15% stuttering. Participants listened to 4 experimental text samples at only 1 stuttering frequency. After hearing the text samples, each listener performed a free recall task, answered cued recall questions, answered story comprehension questions, and rated their perceived mental effort. Free and cued recall as well as story comprehension scores were higher for narrative than for expository texts. Free and cued recall scores were better for familiar than for unfamiliar stories, although topic familiarity did not affect story comprehension scores. Samples with all levels of stuttering resulted in higher mental effort ratings for both text types and topic familiarities. Stuttering has a greater influence on listener recall and comprehension for narrative than for expository texts. Topic familiarity affects free and cued recall but has no influence on story comprehension. Regardless of the amount of stuttering, mental effort was high for both text types and levels of familiarity.
Blank, Mei-Ling; Connor, Jennie; Gray, Andrew; Tustin, Karen
2016-03-01
We aimed to quantify associations between drinking and mental well-being, self-esteem and general self-efficacy among New Zealand university students approaching graduation. A web-based survey was conducted across all eight New Zealand universities in 2011. Participants were enrolled in their final year of a bachelor degree or a higher qualification and were aged 25 years and under (n = 5082, response level 65 %). Measures included the Alcohol Use Disorders Identification Test-Consumption, Warwick-Edinburgh Mental Well-being Scale, and items from the Rosenberg Self-esteem Scale and General Self-efficacy Scale. Linear regression models were used to estimate associations between the psychological measures and (1) drinking patterns for all participants (abstention/moderate/hazardous); and (2) consumption indicators for non-abstaining participants (frequency/quantity/heavy drinking frequency), adjusting for a range of individual, social and personality characteristics, separately for men and women. Lower mental well-being was associated with a moderate or hazardous drinking pattern for men, and a hazardous pattern for women, compared to abstaining participants. Higher self-esteem was associated with any level of heavy drinking frequency for men, while the heaviest drinking women had a pattern of lower self-esteem. There was a general pattern of higher general self-efficacy for men and women who drank alcohol. We observed that higher levels of drinking were associated with small, yet statistically significant, differences in psychological outcomes for men and women. Our findings are of uncertain clinical significance; however, they underscore the importance of investigating a fuller range of social and personality factors that may confound the association of drinking and psychological outcomes.
Representations of Spectral Differences between Vowels in Tonotopic Regions of Auditory Cortex
ERIC Educational Resources Information Center
Fisher, Julia
2017-01-01
This work examines the link between low-level cortical acoustic processing and higher-level cortical phonemic processing. Specifically, using functional magnetic resonance imaging, it looks at 1) whether or not the vowels [alpha] and [i] are distinguishable in regions of interest defined by the first two resonant frequencies (formants) of those…
ERIC Educational Resources Information Center
Gifford, Rene H.; Dorman, Michael F.; McKarns, Sharon A.; Spahr, Anthony J.
2007-01-01
Purpose: The authors assessed whether (a) a full-insertion cochlear implant would provide a higher level of speech understanding than bilateral low-frequency acoustic hearing, (b) contralateral acoustic hearing would add to the speech understanding provided by the implant, and (c) the level of performance achieved with electric stimulation plus…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jesser, Renee D.; Li, Shaobing; Weinberg, Adriana
2006-09-01
HIV-infected patients fail to fully recover cell-mediated immunity despite HAART. To identify regulatory factors, we studied the phenotype and function of in vitro cytomegalovirus (CMV)-stimulated T cells from HAART recipients. CFSE-measured proliferation showed CD4{sup +} and CD8{sup +} cells dividing in CMV-stimulated cultures. Compared with healthy controls, CMV-stimulated lymphocytes from HAART recipients had lower {sup 3}H-thymidine incorporation; lower IFN{gamma} and TNF{alpha} production; higher CD4{sup +}CD27{sup -}CD28{sup -} and CD8{sup +}CD27{sup -}CD28{sup -} frequencies; lower CD4{sup +}CD25{sup hi}; and higher FoxP3 expression in CD8{sup +}CD25{sup hi} cells. CMV-specific proliferation correlated with higher IFN{gamma}, TNF{alpha} and IL10 levels and higher CD4{sup +}perforin{supmore » +} and CD8{sup +}perforin{sup +} frequencies. Decreased proliferation correlated with higher CD4{sup +}CD27{sup -}CD28{sup -} frequencies and TGF{beta}1 production, which also correlated with each other. Anti-TGF{beta}1 neutralizing antibodies restored CMV-specific proliferation in a dose-dependent fashion. In HIV-infected subjects, decreased proliferation correlated with higher CMV-stimulated CD8{sup +}CD25{sup hi} frequencies and their FoxP3 expression. These data indicate that FoxP3- and TGF{beta}1-expressing regulatory T cells contribute to decreased immunity in HAART recipients.« less
Billangeon, P-M; Pierre, F; Bouchiat, H; Deblock, R
2007-03-23
A single-Cooper-pair transistor (SCPT) is coupled capacitively to a voltage biased Josephson junction, used as a high-frequency generator. Thanks to the high energy of photons generated by the Josephson junction, transitions between energy levels, not limited to the first two levels, were induced and the effect of this irradiation on the dc Josephson current of the SCPT was measured. The phase and gate bias dependence of energy levels of the SCPT at high energy is probed. Because the energies of photons can be higher than the superconducting gap we can induce not only transfer of Cooper pairs but also transfer of quasiparticles through the island of the SCPT, thus controlling the poisoning of the SCPT. This can both decrease and increase the average Josephson energy of the SCPT: its supercurrent is then controlled by high-frequency irradiation.
Fabijańska, Anna; Smurzyński, Jacek; Hatzopoulos, Stavros; Kochanek, Krzysztof; Bartnik, Grażyna; Raj-Koziak, Danuta; Mazzoli, Manuela; Skarżyński, Piotr H; Jędrzejczak, Wieslaw W; Szkiełkowska, Agata; Skarżyński, Henryk
2012-12-01
The aim of this study was to evaluate distortion product otoacoustic emissions (DPOAEs) and extended high-frequency (EHF) thresholds in a control group and in patients with normal hearing sensitivity in the conventional frequency range and reporting unilateral tinnitus. Seventy patients were enrolled in the study: 47 patients with tinnitus in the left ear (Group 1) and 23 patients with tinnitus in the right ear (Group 2). The control group included 60 otologically normal subjects with no history of pathological tinnitus. Pure-tone thresholds were measured at all standard frequencies from 0.25 to 8 kHz, and at 10, 12.5, 14, and 16 kHz. The DPOAEs were measured in the frequency range from approximately 0.5 to 9 kHz using the primary tones presented at 65/55 dB SPL. The left ears of patients in Group 1 had higher median hearing thresholds than those in the control subjects at all 4 EHFs, and lower mean DPOAE levels than those in the controls for almost all primary frequencies, but significantly lower only in the 2-kHz region. Median hearing thresholds in the right ears of patients in Group 2 were higher than those in the right ears of the control subjects in the EHF range at 12.5, 14, and 16 kHz. The mean DPOAE levels in the right ears were lower in patients from Group 2 than those in the controls for the majority of primary frequencies, but only reached statistical significance in the 8-kHz region. Hearing thresholds in tinnitus ears with normal hearing sensitivity in the conventional range were higher in the EHF region than those in non-tinnitus control subjects, implying that cochlear damage in the basal region may result in the perception of tinnitus. In general, DPOAE levels in tinnitus ears were lower than those in ears of non-tinnitus subjects, suggesting that subclinical cochlear impairment in limited areas, which can be revealed by DPOAEs but not by conventional audiometry, may exist in tinnitus ears. For patients with tinnitus, DPOAE measures combined with behavioral EHF hearing thresholds may provide additional clinical information about the status of the peripheral hearing.
Ghoti, Hussam; Fibach, Eitan; Rachmilewitz, Eliezer A; Jeadi, Hisham; Filon, Dvora
2017-03-01
β-Thalassemia (β-thal) is a very common disease in the Palestinian population of the Gaza Strip. We studied their mutation frequency and clinical features. Thirteen different mutations were identified. The most common mutation was IVS-I-1 (G>A) (HBB: c.92+1G>A), which was prevalent in 31.5% of the thalassemia alleles studied. The IVS-I-110 (G>A) (HBB: c.93-21G>A) mutation was found in 25.0% of the alleles. Homozygotes for the IVS-I-1 mutation had higher mean hemoglobin (Hb) levels, required less blood transfusions, and lower transferrin saturation than the homozygotes for the IVS-I-110 mutation. This milder phenotype was, most likely, the result of the persistent production of Hb F; it was 9-fold higher in absolute terms (g/dL) and 7.7-fold higher in relative terms (percentage of total Hb). About half of our IVS-I-1 patients carried the XmnI polymorphism, which is known to be associated with elevated Hb F levels.
Jo, Wan-Kuen; Lee, Jong-Hyo; Kim, Mo-Keun
2008-02-01
The present study investigated the emission characteristics of gel-type air fresheners (AFs), using head-space, small-chamber, and in-vehicle tests. Five toxic or hazardous analytes were found in the headspace phase of AFs (toluene, benzene, ethyl benzene, and m,p-xylene) at a frequency of more than 50%. Limonene and linalool, which are known to be unsaturated ozone-reactive VOCs, were detected at a frequency of 58 and 35%, respectively. The empirical model fitted well with the time-series concentrations in the chamber, thereby suggesting that the empirical model was suitable for testing emissions. Limonene exhibited the highest emission rate, followed by m,p-xylene, toluene, ethyl benzene, and benzene. For most target VOCs, higher air change per hour (ACH) levels exhibited increased emission rates. In contrast, higher ACH levels resulted in lower chamber concentrations. The mean concentration of limonene was significantly higher in passenger cars with an AF than without. For other target compounds, there were no significant differences between the two conditions tested. Consequently, it was suggested that unlike limonene, the emission strength for aromatic compounds identified in the chamber tests was not strong enough to elevate in-vehicle levels.
Light weight polarized polypropylene foam for noise shielding
NASA Astrophysics Data System (ADS)
Zelfer, Travis J.; Warne, Derik S.; Korde, Umesh A.
2009-03-01
The high levels of noise generated during launch can destroy sensitive equipment on space craft. Passive damping systems, like acoustic blankets, work to reduce the high frequency noise but do little to the low frequency noise (<400 Hz). While wall mounted transducers can reduce the low frequency noise during a launch, they also can create areas of higher increased sound pressure in the payload fairings. Ferroelectret cellular polymer foams with high piezoelectric coupling constants are being used as new types of actuators and sensors. Further impedance control through the inverse piezoelectric effect will lead to a new "semi-active" approach that will reduce low frequency noise levels. Combining layers of conventional nonpiezoelectric foam and ferroelectret materials with a multiple loop feedback system will give a total damping effect that is adaptable over a wide band of low frequencies. This paper covers the manufacturing methods that were used to make polarized polypropylene foam, to test the foam for its polarized response and its noise shielding ability.
How Frequency of Electrosurgical Current and Electrode Size Affect the Depth of Electrocoagulation.
Taheri, Arash; Mansoori, Parisa; Bahrami, Naeim; Alinia, Hossein; Watkins, Casey E; Feldman, Steven R
2016-02-01
Many factors affect the depth of electrocoagulation. To evaluate the effect of current frequency and electrode size on the depth of electrocoagulation. In this in vitro study, 4 cylindrical electrodes (2, 2.3, 3, and 4 mm) were used to apply 3 electrosurgical currents (0.4, 1.5, and 3 MHz) to bovine liver. Each electrode was placed at different points on the surface of the liver, and energy at various levels and frequencies was delivered to the tissue. Subsequently, cross-sections of the liver were analyzed. Coagulation started at the periphery of the electrode-tissue contact area. With higher energy levels, coagulation spreads to involve the remainder of the contact area. Neither the frequency nor the electrode size had any effect on this coagulation pattern. The frequency of the current also did not show any relation with depth of coagulation; however, there was a direct correlation between the size of the electrode and the depth of coagulation. Larger-tip electrodes provided deeper coagulation compared with finer-tip electrodes.
[Nutritional status of school children from different socioeconomic levels].
Amigo, H; Bustos, P; Radrigán, M E; Ureta, E
1995-09-01
The aim of this work was to compare the nutritional status of children from low and high socioeconomic levels. Weight, height, mid arm circumference and tricipital skinfold thickness were measured in 1,842 children of low and 2,770 of high socioeconomic status. Mean weight, height, and mid arm muscular circumference were higher in children of high socioeconomic status. Also, growth failure and overweight had a higher frequency among children of low socioeconomic status. Mean weight, height and mid arm circumference were higher in males of both groups. Among children of low socioeconomic status, height/age ratios were lower in men and weight/height ratios were higher in women. These differences were not observed in children of high socioeconomic level. We conclude that adverse environmental conditions, lower physical activity and indigenous ancestors may alter the nutritional status of children of low socioeconomic levels.
Characterization and Impact of Low Frequency Wind Turbine Noise Emissions
NASA Astrophysics Data System (ADS)
Finch, James
Wind turbine noise is a complex issue that requires due diligence to minimize any potential impact on quality of life. This study enhances existing knowledge of wind turbine noise through focused analyses of downwind sound propagation, directionality, and the low frequency component of the noise. Measurements were conducted at four wind speeds according to a design of experiments at incremental distances and angles. Wind turbine noise is shown to be highly directional, while downwind sound propagation is spherical with limited ground absorption. The noise is found to have a significant low frequency component that is largely independent of wind speed over the 20-250 Hz range. The generated low frequency noise is shown to be audible above 40 Hz at the MOE setback distance of 550 m. Infrasound levels exhibit higher dependency on wind speed, but remain below audible levels up to 15 m/s.
Low frequency dove coos vary across noise gradients in an urbanized environment.
Guo, Fengyi; Bonebrake, Timothy C; Dingle, Caroline
2016-08-01
Urbanization poses a challenge to bird communication due to signal masking by ambient noise and reflective surfaces that lead to signal degradation. Bird species (especially oscines) have been shown to alter their singing behaviour to increase signal efficiency in highly urbanized environments. However, few studies on the effects of noise on song structure have included birds with low frequency vocal signals which may be especially vulnerable to noise pollution due to significant frequency overlap of their signals with traffic noise. We compared the perch coos of spotted doves (Streptopelia chinensis), a species with very low frequency vocalizations, in different background noise levels across urban and peri-urban areas in Hong Kong. We documented a 10% upward shift in the minimum frequency of coos of spotted doves across the noise gradient (a relatively small but significant shift), and a reduced maximum frequency in urban habitats with a higher density of built up area. Hong Kong doves had significantly higher minimum and maximum frequencies than doves from throughout their range (from mostly rural sites). Our results indicate that urban species with extremely low sound frequencies such as doves can alter their vocalizations in response to variable urban acoustic environments. Copyright © 2016 Elsevier B.V. All rights reserved.
Garinis, Angela C; Liao, Selena; Cross, Campbell P; Galati, Johnathan; Middaugh, Jessica L; Mace, Jess C; Wood, Anna-Marie; McEvoy, Lindsey; Moneta, Lauren; Lubianski, Troy; Coopersmith, Noe; Vigo, Nicholas; Hart, Christopher; Riddle, Artur; Ettinger, Olivia; Nold, Casey; Durham, Heather; MacArthur, Carol; McEvoy, Cynthia; Steyger, Peter S
2017-06-01
Hearing loss rates in infants admitted to neonatal intensive care units (NICU) run at 2-15%, compared to 0.3% in full-term births. The etiology of this difference remains poorly understood. We examined whether the level of ambient sound and/or cumulative gentamicin (an aminoglycoside) exposure affect NICU hearing screening results, as either exposure can cause acquired, permanent hearing loss. We hypothesized that higher levels of ambient sound in the NICU, and/or gentamicin dosing, increase the risk of referral on the distortion product otoacoustic emission (DPOAE) assessments and/or automated auditory brainstem response (AABR) screens. This was a prospective pilot outcomes study of 82 infants (<37 weeks gestational age) admitted to the NICU at Oregon Health & Science University. An ER-200D sound pressure level dosimeter was used to collect daily sound exposure in the NICU for each neonate. Gentamicin dosing was also calculated for each infant, including the total daily dose based on body mass (mg/kg/day), as well as the total number of treatment days. DPOAE and AABR assessments were conducted prior to discharge to evaluate hearing status. Exclusion criteria included congenital infections associated with hearing loss, and congenital craniofacial or otologic abnormalities. The mean level of ambient sound was 62.9 dBA (range 51.8-70.6 dBA), greatly exceeding American Academy of Pediatrics (AAP) recommendation of <45.0 dBA. More than 80% of subjects received gentamicin treatment. The referral rate for (i) AABRs, (frequency range: ∼1000-4000 Hz), was 5%; (ii) DPOAEs with a broad F2 frequency range (2063-10031 Hz) was 39%; (iii) DPOAEs with a low-frequency F2 range (<4172 Hz) was 29%, and (iv) DPOAEs with a high-frequency F2 range (>4172 Hz) was 44%. DPOAE referrals were significantly greater for infants receiving >2 days of gentamicin dosing compared to fewer doses (p = 0.004). The effect of sound exposure and gentamicin treatment on hearing could not be determined due to the low number of NICU infants without gentamicin exposure (for control comparisons). All infants were exposed to higher levels of ambient sound that substantially exceed AAP guidelines. More referrals were generated by DPOAE assessments than with AABR screens, with significantly more DPOAE referrals with a high-frequency F2 range, consistent with sound- and/or gentamicin-induced cochlear dysfunction. Adding higher frequency DPOAE assessments to existing NICU hearing screening protocols could better identify infants at-risk for ototoxicity. Copyright © 2017 Elsevier B.V. All rights reserved.
Garinis, Angela C.; Liao, Selena; Cross, Campbell P.; Galati, Johnathan; Middaugh, Jessica L.; Mace, Jess C.; Wood, Anna-Marie; McEvoy, Lindsey; Moneta, Lauren; Lubianski, Troy; Coopersmith, Noe; Vigo, Nicholas; Hart, Christopher; Riddle, Artur; Ettinger, Olivia; Nold, Casey; Durham, Heather; MacArthur, Carol; McEvoy, Cynthia; Steyger, Peter S.
2017-01-01
Objective Hearing loss rates in infants admitted to neonatal intensive care units (NICU) run at 2–15%, compared to 0.3% in full-term births. The etiology of this difference remains poorly understood. We examined whether the level of ambient sound and/or cumulative gentamicin (an aminoglycoside) exposure affect NICU hearing screening results, as either exposure can cause acquired, permanent hearing loss. We hypothesized that higher levels of ambient sound in the NICU, and/or gentamicin dosing, increase the risk of referral on the distortion product otoacoustic emission (DPOAE) assessments and/or automated auditory brainstem response (AABR) screens. Methods This was a prospective pilot outcomes study of 82 infants (<37 weeks gestational age) admitted to the NICU at Oregon Health & Science University. An ER-200D sound pressure level dosimeter was used to collect daily sound exposure in the NICU for each neonate. Gentamicin dosing was also calculated for each infant, including the total daily dose based on body mass (mg/kg/day), as well as the total number of treatment days. DPOAE and AABR assessments were conducted prior to discharge to evaluate hearing status. Exclusion criteria included congenital infections associated with hearing loss, and congenital craniofacial or otologic abnormalities. Results The mean level of ambient sound was 62.9 dBA (range 51.8–70.6 dBA), greatly exceeding American Academy of Pediatrics (AAP) recommendation of <45.0 dBA. More than 80% of subjects received gentamicin treatment. The referral rate for (i) AABRs, (frequency range: ~1000–4000 Hz), was 5%; (ii) DPOAEs with a broad F2 frequency range (2063–10031 Hz) was 39%; (iii) DPOAEs with a low-frequency F2 range (<4172 Hz) was 29%, and (iv) DPOAEs with a high-frequency F2 range (>4172 Hz) was 44%. DPOAE referrals were significantly greater for infants receiving >2 days of gentamicin dosing compared to fewer doses (p= 0.004). The effect of sound exposure and gentamicin treatment on hearing could not be determined due to the low number of NICU infants without gentamicin exposure (for control comparisons). Conclusion All infants were exposed to higher levels of ambient sound that substantially exceed AAP guidelines. More referrals were generated by DPOAE assessments than with AABR screens, with significantly more DPOAE referrals with a high-frequency F2 range, consistent with sound- and/or gentamicin-induced cochlear dysfunction. Adding higher frequency DPOAE assessments to existing NICU hearing screening protocols could better identify at-risk infants to be referred for diagnostic evaluation. PMID:28483249
Wang, Tian; Deng, Qi-fei; Zhang, Xiao; Li, Xiao-liang; Deng, Si-yun; Dai, Xia-yun; Huang, Su-li; Feng, Jing; Li, Jun; Wu, Tang-chun; Guo, Huan
2013-08-01
To investigate the association of rs2910164 G > C polymorphism and rs11614913 T > C polymorphism in pre-miR-146a and pre-miR-196a2 with genetic damage levels in coke oven workers. A total of 575 nonsmoking workers who have worked for more than one year in a coke-oven plant at Wuhan, Hubei Province were enrolled in this study in September to October, 2010. The general characteristics as well as blood and urine samples were collected. The genetic damage levels were detected by cytokinesis-block micronucleus cytom assay and represented as micronucleus (MN) frequencies of binucleate cells in peripheral blood lymphocytes. The rs2910164 G > C polymorphisms in pre-miR-146a and rs11614913 T > C polymorphisms in pre-miR-196a2 were genotyped by using TaqMan assay. The plasma concentrations of benzo[a]pyrene-diolepoxide (BPDE)-albumin adducts were determined by using ELISA. All data were analyzed, the frequency ratio (FR) and 95%CI were calculated. Totally, 575 workers were taken into consideration. The rs2910164 C allele was associated with increased MN frequencies in the coke oven workers (P trend = 0.025), and the MN frequencies were higher in rs2910164 CC genotype carriers (4.38 ± 3.46) than in wild-type rs2910164 GG genotype carriers (4.02 ± 3.09) (FR = 1.18, 95%CI:1.04-1.34). The further stratified analyses by working years, gender, alcohol consumption, and the levels of BPDE-albumin adducts showed that the effects of rs2910164 C allele in increasing MN frequencies were robust in subjects who were males (FR = 1.11, 95%CI:1.02-1.20), nondrinkers (FR = 1.07, 95%CI:1.00-1.14), working years less than 20 (FR = 1.12, 95%CI:1.03-1.22), and workers with lower BPDE-albumin adducts levels (FR = 1.11, 95%CI:1.02-1.21) (P trend = 0.011, 0.044, 0.006 and 0.020, respectively). In addition, the MN frequencies were higher in workers with rs11614913 TC genotype (4.27 ± 2.91) than workers with rs11614913 TT genotype (3.90 ± 3.32) (FR = 1.12, 95%CI:1.02-1.23).Workers carried both rs2910164 GG and rs11614913 TT genotypes were set as a control, and the MN frequencies of workers with both rs2910164 CC and rs11614913 CC genotypes (5.32 ± 4.94) were 1.51 (1.21-1.89) times higher than the control (3.75 ± 3.01). The rs2910164 C allele in pre-miR-146a and rs11614913 C allele in pre-miR-196a2 were associated with increased genetic damage levels in coke oven workers.
NASA Technical Reports Server (NTRS)
Podwysocki, M. H.
1974-01-01
Two study areas in a cratonic platform underlain by flat-lying sedimentary rocks were analyzed to determine if a quantitative relationship exists between fracture trace patterns and their frequency distributions and subsurface structural closures which might contain petroleum. Fracture trace lengths and frequency (number of fracture traces per unit area) were analyzed by trend surface analysis and length frequency distributions also were compared to a standard Gaussian distribution. Composite rose diagrams of fracture traces were analyzed using a multivariate analysis method which grouped or clustered the rose diagrams and their respective areas on the basis of the behavior of the rays of the rose diagram. Analysis indicates that the lengths of fracture traces are log-normally distributed according to the mapping technique used. Fracture trace frequency appeared higher on the flanks of active structures and lower around passive reef structures. Fracture trace log-mean lengths were shorter over several types of structures, perhaps due to increased fracturing and subsequent erosion. Analysis of rose diagrams using a multivariate technique indicated lithology as the primary control for the lower grouping levels. Groupings at higher levels indicated that areas overlying active structures may be isolated from their neighbors by this technique while passive structures showed no differences which could be isolated.
Koo, Soo Kweon; Kwon, Soon Bok; Kim, Yang Jae; Moon, J I Seung; Kim, Young Jun; Jung, Sung Hoon
2017-03-01
Snoring is a sign of increased upper airway resistance and is the most common symptom suggestive of obstructive sleep apnea. Acoustic analysis of snoring sounds is a non-invasive diagnostic technique and may provide a screening test that can determine the location of obstruction sites. We recorded snoring sounds according to obstruction level, measured by DISE, using a smartphone and focused on the analysis of formant frequencies. The study group comprised 32 male patients (mean age 42.9 years). The spectrogram pattern, intensity (dB), fundamental frequencies (F 0 ), and formant frequencies (F 1 , F 2 , and F 3 ) of the snoring sounds were analyzed for each subject. On spectrographic analysis, retropalatal level obstruction tended to produce sharp and regular peaks, while retrolingual level obstruction tended to show peaks with a gradual onset and decay. On formant frequency analysis, F 1 (retropalatal level vs. retrolingual level: 488.1 ± 125.8 vs. 634.7 ± 196.6 Hz) and F 2 (retropalatal level vs. retrolingual level: 1267.3 ± 306.6 vs. 1723.7 ± 550.0 Hz) of retrolingual level obstructions showed significantly higher values than retropalatal level obstruction (p < 0.05). This suggests that the upper airway is more severely obstructed with retrolingual level obstruction and that there is a greater change in tongue position. Acoustic analysis of snoring is a non-invasive diagnostic technique that can be easily applied at a relatively low cost. The analysis of formant frequencies will be a useful screening test for the prediction of occlusion sites. Moreover, smartphone can be effective for recording snoring sounds.
Relation between salivary cortisol as stress biomarker and dietary pattern in children.
Michels, Nathalie; Sioen, Isabelle; Braet, Caroline; Huybrechts, Inge; Vanaelst, Barbara; Wolters, Maike; De Henauw, Stefaan
2013-09-01
Psychological stress has been suggested to result in hormonal effects (e.g. changes in cortisol pattern) that may change food selection in unhealthy ways. This study examines whether children's dietary pattern is indeed related to salivary cortisol levels. In 323 children (5-10 years old) participating in the Belgian ChiBS study, salivary cortisol samples, a biomarker for stress, was sampled when waking up, 30 and 60 min after wake up and in the evening on two consecutive weekdays. Data on the children's dietary pattern (frequency of sweet foods, fatty foods, snacks, fruit and vegetables) was collected with a food frequency questionnaire. Multilevel time modelling was used with adjustments for sex, age, body mass index, parental education and wake up time. Higher overall cortisol levels and a large cortisol awakening response (CAR) were associated with more frequent consumption of sweet foods. A steeper diurnal cortisol decline was associated with a higher sweet, fatty and snack food consumption frequency. No associations with fruit and vegetables consumption were found. High cortisol levels were linked to an unhealthier dietary pattern (more fatty food, snacks and especially sweet food). This supports the theory of cortisol-induced comfort food preference and strengthens the stress-diet relation. Copyright © 2013 Elsevier Ltd. All rights reserved.
Secondhand smoke and sensorineural hearing loss in adolescents.
Lalwani, Anil K; Liu, Ying-Hua; Weitzman, Michael
2011-07-01
To investigate the hypothesis that second-hand smoke (SHS) exposure is associated with sensorineural hearing loss (SNHL) in adolescents. A complex, multistage, stratified geographic area design for collecting representative data from the noninstitutionalized US population. Cross-sectional data from National Health and Nutrition Examination Survey (2005-2006) were available for 1533 participants 12 to 19 years of age who underwent audiometric testing, had serum cotinine levels available, and were not actively smoking. SNHL was defined as an average pure-tone level greater than 15 dB for 0.5, 1, and 2 kHz (low frequency) and 3, 4, 6, and 8 kHz (high frequency). Secondhand smoke exposure, as assessed by serum cotinine levels, was associated with elevated pure-tone hearing thresholds at 2, 3, and 4 kHz, a higher rate of unilateral low-frequency SNHL (11.8% vs 7.5%; P < .04), and a 1.83-fold increased risk of unilateral low-frequency SNHL in multivariate analyses (95% confidence interval, 1.08-3.41). The prevalence of SNHL was directly related to level of SHS exposure as reflected by serum cotinine levels. In addition, nearly 82% of adolescents with SNHL did not recognize hearing difficulties. Secondhand smoke is associated with elevated pure-tone thresholds and an increased prevalence of low-frequency SNHL that is directly related to level of exposure, and most affected individuals are unaware of the hearing loss. Thus, adolescents exposed to SHS may need to be closely monitored for early hearing loss with periodic audiologic testing.
Tayyem, R F; Al-Hazzaa, H M; Abu-Mweis, S S; Bawadi, H A; Hammad, S S; Musaiger, A O
2014-07-08
The present study examined differences in dietary habits and physical activity levels between students attending private and public high schools in Jordan. A total of 386 secondary-school males and 349 females aged 14-18 years were randomly recruited using a multistage, stratified, cluster sampling technique. Dietary habits and physical activity level were self-reported in a validated questionnaire. The prevalence of obesity was significantly higher among adolescents in private (26.0%) than in public schools (16.7%). The frequency of breakfast intake was significantly higher among adolescents in private schools, whereas French fries and sweets intake was significantly higher in public schools. Television viewing showed a significant interaction with school type by sex. A higher rate of inactivity was found among students attending private schools. Despite a slightly better overall dietary profile for students in private schools, they had a higher rate of overweight and obesity compared with those in public schools.
Kašuba, V; Rozgaj, R; Milić, M; Zelježić, D; Kopjar, N; Pizent, A; Kljaković-Gašpić, Z; Jazbec, A
2012-10-01
We investigated genotoxic effects of occupational exposure to lead acetate in pottery-glaze ceramic workers. The study was carried out in 30 exposed workers and 30 matched controls, to whom several biochemical parameters-the blood lead (B-Pb; range: exposed, 41.68-404.77; controls, 12-52) and cadmium (B-Cd) level, the activity of delta-aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin (EP), the level of vitamin B(12) and folate in serum-were measured. The genotoxic effects were evaluated by the alkaline comet assay, the DNA diffusion assay and micronucleus test in peripheral blood lymphocytes. Subjects exposed to lead had significantly higher B-Pb level and, consequently, increased values of tail intensity (TI), frequency of apoptotic and necrotic cells, and frequency of micronuclei (MN). In contrast, their activity of ALAD, the level of vitamin B(12) and folate in serum were significantly lower compared to controls. Poisson regression analysis showed a significant correlation of profession, duration of exposure, smoking, level of cadmium in blood, ALAD and EP with primary DNA damage. A majority of primary damage repairs in a short period after exposure to a genotoxic agent. In addition, the influence of gender and level of vitamin B(12) and folate in serum MN frequency in exposed group was observed. In this study, DNA diffusion and micronucleus test showed higher influence of tested parameters to DNA damage. The results indicate a need for concomitant use of at least two different biomarkers of exposure when estimating a genetic risk of lead exposure.
Gan, Run-Tao; Yang, Shu-Sen
2012-04-01
To determine whether leptin receptor (LEPR) 223A>G polymorphism has an effect on the plasma leptin levels and the macroangiopathic complications in type 2 diabetes mellitus (T2DM). The genotypes and allelic frequencies of the LEPR 223A>G were examined with polymerase chain reaction and restriction fragment length polymorphism in 301 patients with T2DM and 172 unrelated healthy subjects. The plasma concentrations of leptin were determined in all subjects. The mean plasma leptin levels in the T2DM group were significantly higher than that of controls and the plasma levels of leptin were higher in diabetic patients with macroangiopathy than in patients without macroangiopathy (P < 0.05). The genotype (GG, AG and AA) distribution of 223A>G polymorphism was 58.3, 32.5, and 9.2% in diabetic patients with macroangiopathy, 75.3, 22.1, and 2.6% in patients without macroangiopathy, and 70.3, 27.5, 2.2% in controls respectively, a significant difference was found between diabetic patients with and without macroangiopathy (P < 0.05). The frequency of the allele A was higher in patients with macroangiopathy than in patients without macroangiopathy (25.6 vs. 16.3%; P < 0.05). Moreover, the plasma leptin levels were markedly higher in patients with AA genotype than those with AG or GG genotype in patients with macroangiopathy (P < 0.05). The LEPR 223A>G gene polymorphism associated with a predisposition to increased plasma leptin levels could constitute a useful predictive marker for diabetic macroangiopathy.
Influence of controlled ovarian hyperstimulation on uterine peristalsis in infertile women.
Zhu, Lin; Li, Yanping; Xu, Aizhuang
2012-09-01
Is there a difference in the characteristics of uterine peristalsis in natural and controlled ovarian hyperstimulation (COH) cycles? COH significantly changed the uterine peristaltic pattern. In natural menstrual cycles, the periodic changes of uterine peristalsis are closely related to the reproductive process. This is a prospective cohort study with a total of 64 subjects involved. The study was performed between May 2011 and August 2011. Sixty-four infertile women with regular, ovulatory menstrual cycles underwent follicular tracking in one natural cycle and after ovarian stimulation (GnRH-agonist down-regulation) in the subsequent cycle (COH). Three time points were studied in both cycles: at LH surge/HCG plus 1 day, ovulation/oocyte retrieval and 2 days after ovulation/retrieval. The study was performed in an IVF center of the university-affiliated Xiangya hospital. Uterine peristaltic wave frequency was 1.31 times higher in the COH than in the natural cycle (P< 0.01). At all three time points in the COH cycle, waves moving from the cervix to fundus dominated, comprising 80-90% of the wave types observed, while 'no activity' was more frequently observed in the natural cycle. The wave frequency was positively correlated with the level of serum estradiol (E(2)) (r= 0.30; P< 0.01) and negatively correlated with the progesterone level (r= -0.48; P< 0.01) for the physiological range of steroid levels. No correlation was found between the wave frequency and supraphysiological concentrations of E(2) or progesterone. The two observers were not independent and this was a limitation of the study. Quantitative measurements of wave amplitude in the different cycles should be compared in future research. Uterine peristalsis was much higher in the COH cycle than in the natural cycle. The endometrial movements did not weaken to the natural level before embryo transfer, even with high levels of progesterone. The wave frequency was positively correlated with serum E(2) level and negatively correlated with that of progesterone within the physiological range. No correlation was found between the wave frequency and supraphysiological concentrations of E(2) and progesterone.
Effect of chevron nozzle penetration on aero-acoustic characteristics of jet at M = 0.8
NASA Astrophysics Data System (ADS)
Nikam, S. R.; Sharma, S. D.
2017-12-01
Aero-acoustic characteristics of a high-speed jet with chevron nozzles are experimentally investigated at a Mach number of 0.8. The main focus is to examine the effects of the extent of chevron penetration and its position in the mixing layer. Chevron nozzles with three different levels of penetration employed at three different longitudinal locations from the nozzle lip are tested, and the results are compared with those of a plain baseline nozzle. The chevrons are found to produce a lobed shear layer through the notched region, thereby increasing the surface area of the jet, particularly in the close vicinity of the nozzle, which increases the mixing and reduces the potential core length. This effect becomes more prominent with increasing penetration closer to the nozzle lip in the thinner mixing layer. Near field and far field noise measurements show distinctly different acoustic features due to chevrons. The chevrons are found to effectively shift the dominant noise source upstream closer to the nozzle. Present investigation proposes a simpler method for locating the dominant noise source from the peak of the centerline velocity decay rate. The overall noise levels registered along the jet edge immediately downstream of the chevrons are higher, but further downstream they are reduced in comparison with the plain baseline nozzle. Also, the chevrons beam the noise towards higher polar angles at higher frequencies. At shallow polar angles with respect to the jet axis in the far field, chevrons suppress the noise at low frequencies with increasing penetration, but for higher polar angles, while they continue to suppress the low frequency noise, at higher frequencies the trend is found to reverse. The noise measured in the near field close to the jet edge is composed of two components: acoustic and hydrodynamic. Of these two components, the chevrons are found to reduce the hydrodynamic component in comparison with the acoustic one.
Vega-Garzon, Lina Patricia; Gomez-Miranda, Ingry Natalia; Peñuela, Gustavo A
2018-05-01
Response Surface Methodology was used for optimizing operating variables for a multi-frequency ultrasound reactor using BP-3 as a model compound. The response variable was the Triclosan degradation percent after 10 sonication min. Frequency at levels from 574, 856 and 1134 kHz were used. Power density, pulse time (PT), silent time (ST) and PT/ST ratio effects were also analyzed. 2 2 and 2 3 experimental designs were used for screening purposes and a central composite design was used for optimization. An optimum value of 79.2% was obtained for a frequency of 574 kHz, a power density of 200 W/L, and a PT/ST ratio of 10. Significant variables were frequency and power level, the first having an optimum value after which degradation decreases while power density level had a strong positive effect on the whole operational range. PT, ST, and PT/ST ratio were not significant variables although it was shown that pulsed mode ultrasound has better degradation rates than continuous mode ultrasound; the effect less significant at higher power levels. Copyright © 2017. Published by Elsevier B.V.
Northoff, Georg
2017-09-01
Consciousness research has much focused on faster frequencies like alpha or gamma while neglecting the slower ones in the infraslow (0.001-0.1Hz) and slow (0.1-1Hz) frequency range. These slower frequency ranges have a "bad reputation" though; their increase in power can observed during the loss of consciousness as in sleep, anesthesia, and vegetative state. However, at the same time, slower frequencies have been conceived instrumental for consciousness. The present paper aims to resolve this paradox which I describe as "paradox of slow frequencies". I first show various data that suggest a central role of slower frequencies in integrating faster ones, i.e., "temporo-spatial integration and nestedness". Such "temporo-spatial integration and nestedness" is disrupted during the loss of consciousness as in anesthesia and sleep leading to "temporo-spatial fragmentation and isolation" between slow and fast frequencies. Slow frequencies are supposedly mediated by neural activity in upper cortical layers in higher-order associative regions as distinguished from lower cortical layers that are related to faster frequencies. Taken together, slower and faster frequencies take on different roles for the level/state of consciousness. Faster frequencies by themselves are sufficient and thus a neural correlate of consciousness (NCC) while slower frequencies are a necessary non-sufficient condition of possible consciousness, e.g., a neural predisposition of the level/state of consciousness (NPC). This resolves the "paradox of slow frequencies" in that it assigns different roles to slower and faster frequencies in consciousness, i.e., NCC and NPC. Taken as NCC and NPC, fast and slow frequencies including their relation as in "temporo-spatial integration and nestedness" can be considered a first "building bloc" of a future "temporo-spatial theory of consciousness" (TTC) (Northoff, 2013; Northoff, 2014b; Northoff & Huang, 2017). Copyright © 2017 Elsevier Inc. All rights reserved.
Evaluation of the impact of urban pollution on the quality of skin: a multicentre study in Mexico.
Lefebvre, M-A; Pham, D-M; Boussouira, B; Bernard, D; Camus, C; Nguyen, Q-L
2015-06-01
After pilot and preliminary studies aimed at identifying pertinent biochemical parameters, a multicenter clinical study was performed to evaluate the effect of pollution on human skin. The clinical study was performed in collaboration with the 'Centre Régional de lutte contre le cancer de Montpellier' and the 'National Institute of Public Health of Mexico' on 96 subjects in Mexico City (exposed to pollution) and 93 subjects in Cuernavaca (less exposed to pollution). Both biochemical and clinical skin parameters were studied. The study demonstrated significant quantitative and qualitative modifications of parameters related to sebum excretion in Mexico City compared to Cuernavaca one: An increased level of sebum excretion rate, a lower level of vitamin E and squalene in sebum, an increase of lactic acid and a higher erythematous index on the face of the subjects. In the stratum corneum, a significant higher level of carbonylated proteins and a lower level of IL 1α were noticed, as well as a decrease of ATP concentration with a decrease of chymotrysin like activity, without modifications of corneodesmosin content and trypsin like activity. From a clinical point of view, a higher frequency of atopic and urticarial skins, a higher frequency of red dermographism, an important seborrheic status at the forehead level and a lower level of dandruffs were noted in Mexico City population. The analysis taking into account the sex does not modify the observed results. The study demonstrated an important impact of polluted environmental conditions on skin quality, evidencing important modifications of superficial biochemical parameters. The cause/effects relationships of these modifications remain, however, to be further assessed by a complementary in vitro/in vivo approaches. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Maioli, Tatiani Uceli; Gonçalves, Juliana Lauar; Miranda, Mariana Camila Gonçalves; Martins, Vinícius Dantas; Horta, Laila Sampaio; Moreira, Thais Garcias; Godard, Ana Lucia Brunialti; Santiago, Andrezza Fernanda; Faria, Ana Maria Caetano
2016-02-01
The purpose of the study was to develop a novel diet based on standard AIN93G diet that would be able to induce experimental obesity and impair immune regulation with high concentrations of both carbohydrate and lipids. To compare the effects of this high sugar and butter (HSB) diet with other modified diets, male C57BL/6 mice were fed either mouse chow, or AIN93G diet, or high sugar (HS) diet, or high-fat (HF) diet, or high sugar and butter (HSB) diet for 11 weeks ad libitum. HSB diet induced higher weight gain. Therefore, control AIN93G and HSB groups were chosen for additional analysis. Regulatory T cells were studied by flow cytometry, and cytokine levels were measured by ELISA. Although HF and HSB diets were able to induce a higher weight gain compatible with obesity in treated mice, HSB-fed mice presented the higher levels of serum glucose after fasting and the lowest frequency of regulatory T cells in adipose tissue. In addition, mice that were fed HSB diet presented higher levels of cholesterol and triglycerides, hyperleptinemia, increased resistin and leptin levels as well as reduced adiponectin serum levels. Importantly, we found increased frequency of CD4(+)CD44(+) effector T cells, reduction of CD4(+)CD25(+)Foxp3(+) and Th3 regulatory T cells as well as decreased levels of IL-10 and TGF-β in adipose tissue of HSB-fed mice. Therefore, HSB represents a novel model of obesity-inducing diet that was efficient in triggering alterations compatible with metabolic syndrome as well as impairment in immune regulatory parameters.
Saw, Anne; Berenbaum, Howard; Okazaki, Sumie
2013-03-01
The current study examined perceptions of living up to parental expectations (LPE) and personal standards as possible mediators of the relationship between ethnicity and worry in a sample of 836 Asian American and 856 White American college students. Asian Americans reported higher frequency of academic- and family-related worries, but they did not report higher levels of global tendency to worry. Perceptions of LPE of current academic performance and personal standards for preparation for a future career partially explained ethnic differences in frequency of academic worry. Personal standards and perceptions of LPE for respect for the family partially explained ethnic differences in frequency of family worry. The findings highlight the importance of targeting domain-specific personal standards and perceived parental expectations to reduce worry among Asian Americans.
McNulty, James K; Wenner, Carolyn A; Fisher, Terri D
2016-01-01
The current research used two 8-wave longitudinal studies spanning the first 4-5 years of 207 marriages to examine the potential bidirectional associations among marital satisfaction, sexual satisfaction, and frequency of sex. All three variables declined over time, though the rate of decline in each variable became increasingly less steep. Controlling for these changes, own marital and sexual satisfaction were bidirectionally positively associated with one another; higher levels of marital satisfaction at one wave of assessment predicted more positive changes in sexual satisfaction from that assessment to the next and higher levels of sexual satisfaction at one wave of assessment predicted more positive changes in marital satisfaction from that assessment to the next. Likewise, own sexual satisfaction and frequency of sex were bidirectionally positively associated with one another. Additionally, partner sexual satisfaction positively predicted changes in frequency of sex and own sexual satisfaction among husbands, yet partner marital satisfaction negatively predicted changes in both frequency of sex and own sexual satisfaction. Controlling these associations, marital satisfaction did not directly predict changes in frequency of sex or vice versa. Only the association between partner sexual satisfaction and changes in own sexual satisfaction varied across men and women and none of the key effects varied across the studies. These findings suggest that sexual and relationship satisfaction are intricately intertwined and thus that interventions to treat and prevent marital distress may benefit by targeting the sexual relationship and interventions to treat and prevent sexual distress in marriage may benefit by targeting the marital relationship.
McNulty, James K.; Wenner, Carolyn A.; Fisher, Terri D.
2014-01-01
The current research used two 8-wave longitudinal studies spanning the first 4–5 years of 207 marriages to examine the potential bidirectional associations among marital satisfaction, sexual satisfaction, and frequency of sex. All three variables declined over time, though the rate of decline in each variable became increasingly less steep. Controlling for these changes, own marital and sexual satisfaction were bidirectionally positively associated with one another; higher levels of marital satisfaction at one wave of assessment predicted more positive changes in sexual satisfaction from that assessment to the next and higher levels of sexual satisfaction at one wave of assessment predicted more positive changes in marital satisfaction from that assessment to the next. Likewise, own sexual satisfaction and frequency of sex were bidirectionally positively associated with one another. Additionally, partner sexual satisfaction positively predicted changes in frequency of sex and own sexual satisfaction among husbands, yet partner marital satisfaction negatively predicted changes in both frequency of sex and own sexual satisfaction. Controlling these associations, marital satisfaction did not directly predict changes in frequency of sex or vice versa. Only the association between partner sexual satisfaction and changes in own sexual satisfaction varied across men and women and none of the key effects varied across the studies. These findings suggest that sexual and relationship satisfaction are intricately intertwined and thus that interventions to treat and prevent marital distress may benefit by targeting the sexual relationship and interventions to treat and prevent sexual distress in marriage may benefit by targeting the marital relationship. PMID:25518817
The impact of cochlear fine structure on hearing thresholds and DPOAE levels
NASA Astrophysics Data System (ADS)
Lee, Jungmee; Long, Glenis; Talmadge, Carrick L.
2004-05-01
Although otoacoustic emissions (OAE) are used as clinical and research tools, the correlation between OAE behavioral estimates of hearing status is not large. In normal-hearing individuals, the level of OAEs can vary as much as 30 dB when the frequency is changed less than 5%. These pseudoperiodic variations of OAE level with frequency are known as fine structure. Hearing thresholds measured with high-frequency resolution reveals a similar (up to 15 dB) fine structure. We examine the impact of OAE and threshold fine structures on the prediction of auditory thresholds from OAE levels. Distortion product otoacoustic emissions (DPOAEs) were measured with sweeping primary tones. Psychoacoustic detection thresholds were measured using pure tones, sweep tones, FM tones, and narrow-band noise. Sweep DPOAE and narrow-band threshold estimates provide estimates that are less influenced by cochlear fine structure and should lead to a higher correlation between OAE levels and psychoacoustic thresholds. [Research supported by PSC CUNY, NIDCD, National Institute on Disability and Rehabilitation Research in U.S. Department of Education, and The Ministry of Education in Korea.
[Concentration of thyrotropic hormone and free thyroxin in children with Down's syndrome].
Jiménez-López, V; Arias, A; Arata-Bellabarba, G; Vivas, E; Delgado, M C; Paoli, M
2001-06-01
The incidence of hypothyroidism is higher among children with Down syndrome than among children in the general population. The frequency of hypothyroidism is higher in the areas of endemic goiter than in other areas. The aim of this paper was to study the concentrations of TSH and FT4 in children with Down syndrome residents of Mérida, a region of Venezuelan Andes. At the Centro de Estudio y Prevención del Retardo Mental y Alteraciones en el Desarrollo (CEPREMAD), the thyroid function was studied in 48 children (1 month to 6 years old), who had Down syndrome, and in 123 healthy children of similar ages. All the children were referred to the Center for thyroid function evaluation. Two (4.2%) of the 48 children with Down syndrome had congenital hypothyroidism and 22 (45.8%) had subclinical hypothyroidism (high concentration of thyrotropin-TSH). Among the control children, only 14% had elevated levels of TSH. There were no differences in relation to the gender. In conclusion in children with Down syndrome, the frequency of high concentrations of TSH was three times higher than the frequency among the healthy children. The frequency of hypothyroidism was similar to that found in areas without endemic goiter.
NASA Astrophysics Data System (ADS)
Charaziak, Karolina K.; Siegel, Jonathan H.
2015-12-01
Otoacoustic emissions evoked with transient sounds (TEOAEs) are believed to originate within the tonotopic region of the stimulus in the cochlea via the same mechanisms as emissions evoked with single tones. However, we found that emissions evoked by low frequency (< 3 kHz) single-tones have an extended region of generation (> 6 mm) in chinchillas (Charaziak and Siegel, 2014, ARO Abst., 119). Here we test whether a broad region of generation for low-frequency stimuli is also a characteristic of TEOAEs evoked with 1-kHz tone pips extracted with compression and suppression methods. The TEOAE could be revealed with moderate level suppressors with frequencies extending beyond the stimulus bandwidth (up to 12.1 kHz), with the largest responses obtained with 3.1 - 4.1 kHz suppressors. There was a consistent decline in group delays of suppressor-revealed TEOAEs with increasing suppressor frequency, as expected if higher-frequency suppressors acted on more basal TEOAE generators. Effects of mid- to high-frequency acoustic trauma on TEOAE levels confirm the notion that the suppressors interact with emission components arising near the tonotopic place of the suppressor.
Kim, So Young; Sim, Songyong; Choi, Hyo Geun
2017-01-01
Although an association between energy drinks and suicide has been suggested, few prior studies have considered the role of emotional factors including stress, sleep, and school performance in adolescents. This study aimed to evaluate the association of energy drinks with suicide, independent of possible confounders including stress, sleep, and school performance. In total, 121,106 adolescents with 13-18 years olds from the 2014 and 2015 Korea Youth Risk Behavior Web-based Survey were surveyed for age, sex, region of residence, economic level, paternal and maternal education level, sleep time, stress level, school performance, frequency of energy drink intake, and suicide attempts. Subjective stress levels were classified into severe, moderate, mild, a little, and no stress. Sleep time was divided into 6 groups: < 6 h; 6 ≤ h < 7; 7 ≤ h < 8; 8 ≤ h < 9; and ≥ 9 h. School performance was classified into 5 levels: A (highest), B (middle, high), C (middle), D (middle, low), and E (lowest). Frequency of energy drink consumption was divided into 3 groups: ≥ 3, 1-2, and 0 times a week. The associations of sleep time, stress level, and school performance with suicide attempts and the frequency of energy drink intake were analyzed using multiple and ordinal logistic regression analysis, respectively, with complex sampling. The relationship between frequency of energy drink intake and suicide attempts was analyzed using multiple logistic regression analysis with complex sampling. Higher stress levels, lack of sleep, and low school performance were significantly associated with suicide attempts (each P < 0.001). These variables of high stress level, abnormal sleep time, and low school performance were also proportionally related with higher energy drink intake (P < 0.001). Frequent energy drink intake was significantly associated with suicide attempts in multiple logistic regression analyses (AOR for frequency of energy intake ≥ 3 times a week = 3.03, 95% CI = 2.64-3.49, P < 0.001). Severe stress, inadequate sleep, and low school performance were related with more energy drink intake and suicide attempts in Korean adolescents. Frequent energy drink intake was positively related with suicide attempts, even after adjusting for stress, sleep time, and school performance.
Kim, So Young; Sim, Songyong
2017-01-01
Objective Although an association between energy drinks and suicide has been suggested, few prior studies have considered the role of emotional factors including stress, sleep, and school performance in adolescents. This study aimed to evaluate the association of energy drinks with suicide, independent of possible confounders including stress, sleep, and school performance. Methods In total, 121,106 adolescents with 13–18 years olds from the 2014 and 2015 Korea Youth Risk Behavior Web-based Survey were surveyed for age, sex, region of residence, economic level, paternal and maternal education level, sleep time, stress level, school performance, frequency of energy drink intake, and suicide attempts. Subjective stress levels were classified into severe, moderate, mild, a little, and no stress. Sleep time was divided into 6 groups: < 6 h; 6 ≤ h < 7; 7 ≤ h < 8; 8 ≤ h < 9; and ≥ 9 h. School performance was classified into 5 levels: A (highest), B (middle, high), C (middle), D (middle, low), and E (lowest). Frequency of energy drink consumption was divided into 3 groups: ≥ 3, 1–2, and 0 times a week. The associations of sleep time, stress level, and school performance with suicide attempts and the frequency of energy drink intake were analyzed using multiple and ordinal logistic regression analysis, respectively, with complex sampling. The relationship between frequency of energy drink intake and suicide attempts was analyzed using multiple logistic regression analysis with complex sampling. Results Higher stress levels, lack of sleep, and low school performance were significantly associated with suicide attempts (each P < 0.001). These variables of high stress level, abnormal sleep time, and low school performance were also proportionally related with higher energy drink intake (P < 0.001). Frequent energy drink intake was significantly associated with suicide attempts in multiple logistic regression analyses (AOR for frequency of energy intake ≥ 3 times a week = 3.03, 95% CI = 2.64–3.49, P < 0.001). Conclusion Severe stress, inadequate sleep, and low school performance were related with more energy drink intake and suicide attempts in Korean adolescents. Frequent energy drink intake was positively related with suicide attempts, even after adjusting for stress, sleep time, and school performance. PMID:29135989
Elbakidze, L; Jin, Y H
2015-08-01
Using transnational terrorism data from 1980 to 2000, this study empirically examines the relationships between frequency of participation in transnational terrorism acts and economic development and education improvement. We find an inverse U-shaped association between the frequency of various nationals acting as perpetrators in transnational terrorism acts and per capita income in their respective home countries. As per capita incomes increase from relatively low levels, frequencies of participation in transnational terrorism increase. However, at sufficiently higher levels of per capita income, further increase in per capita income is negatively associated with the rate of participation in transnational terrorism. Education improvement from elementary to secondary is positively correlated with frequency of participation in transnational terrorism events, whereas further improvement from secondary to tertiary level is negatively correlated with participation in transnational terrorism. We also find that citizens of countries with greater openness to international trade, lower degree of income inequality, greater economic freedom, larger proportion of population with tertiary education, and less religious prevalence participate in transnational terrorism events less frequently. © 2015 Society for Risk Analysis.
Chung, King
2012-06-01
Wind noise reduction is a topic of ongoing research and development for hearing aids and cochlear implants. The purposes of this study were to examine spectral characteristics of wind noise generated by directional (DIR) and omnidirectional (OMNI) microphones on different styles of hearing aids and to derive wind noise reduction strategies. Three digital hearing aids (BTE, ITE, and ITC) were fitted to Knowles Electronic Manikin for Acoustic Research. They were programmed to have linear amplification and matching frequency responses between the DIR and OMNI modes. Flow noise recordings were made from 0° to 360° azimuths at flow velocities of 4.5, 9.0, and 13.5 m/s in a quiet wind tunnel. Noise levels were analyzed in one-third octave bands from 100 to 8000 Hz. Comparison of wind noise revealed that DIR generally produced higher noise levels than OMNI for all hearing aids, but it could result in lower levels than OMNI at some frequencies and head angles. Wind noise reduction algorithms can be designed to detect noise levels of DIR and OMNI outputs in each frequency channel, remove the constraint to switch to OMNI in low-frequency channel(s) only, and adopt the microphone mode with lower noise levels to take advantage of the microphone differences.
Aerodynamic sound generation of flapping wing.
Bae, Youngmin; Moon, Young J
2008-07-01
The unsteady flow and acoustic characteristics of the flapping wing are numerically investigated for a two-dimensional model of Bombus terrestris bumblebee at hovering and forward flight conditions. The Reynolds number Re, based on the maximum translational velocity of the wing and the chord length, is 8800 and the Mach number M is 0.0485. The computational results show that the flapping wing sound is generated by two different sound generation mechanisms. A primary dipole tone is generated at wing beat frequency by the transverse motion of the wing, while other higher frequency dipole tones are produced via vortex edge scattering during a tangential motion. It is also found that the primary tone is directional because of the torsional angle in wing motion. These features are only distinct for hovering, while in forward flight condition, the wing-vortex interaction becomes more prominent due to the free stream effect. Thereby, the sound pressure level spectrum is more broadband at higher frequencies and the frequency compositions become similar in all directions.
NASA Astrophysics Data System (ADS)
Singh, Avneet; Papa, Maria Alessandra; Eggenstein, Heinz-Bernd; Zhu, Sylvia; Pletsch, Holger; Allen, Bruce; Bock, Oliver; Maschenchalk, Bernd; Prix, Reinhard; Siemens, Xavier
2016-09-01
We present results of a high-frequency all-sky search for continuous gravitational waves from isolated compact objects in LIGO's fifth science run (S5) data, using the computing power of the Einstein@Home volunteer computing project. This is the only dedicated continuous gravitational wave search that probes this high-frequency range on S5 data. We find no significant candidate signal, so we set 90% confidence level upper limits on continuous gravitational wave strain amplitudes. At the lower end of the search frequency range, around 1250 Hz, the most constraining upper limit is 5.0 ×10-24, while at the higher end, around 1500 Hz, it is 6.2 ×10-24. Based on these upper limits, and assuming a fiducial value of the principal moment of inertia of 1038 kg m2 , we can exclude objects with ellipticities higher than roughly 2.8 ×10-7 within 100 pc of Earth with rotation periods between 1.3 and 1.6 milliseconds.
Acoustic habitat of an oceanic archipelago in the Southwestern Atlantic
NASA Astrophysics Data System (ADS)
Bittencourt, Lis; Barbosa, Mariana; Secchi, Eduardo; Lailson-Brito, José; Azevedo, Alexandre
2016-09-01
Underwater soundscapes can be highly variable, and in natural conditions are often dominated by biological signals and physical features of the environment. Few studies, however, focused on oceanic islands soundscapes. Islands in the middle of ocean basins can provide a good example of how untouched marine soundscapes are. Autonomous acoustic recordings were carried out in two different seasons in Trindade-Martin Vaz Archipelago, Southwestern Atlantic, providing nearly continuous data for both periods. Sound levels varied daily and between seasons. During summer, higher frequencies were noisier than lower frequencies, with snapping shrimp being the dominating sound source. During winter, lower frequencies were noisier than higher frequencies due to humpback whale constant singing. Biological signal detection had a marked temporal pattern, playing an important role in the soundscape. Over 1000 humpback whale sounds were detected hourly during winter. Fish vocalizations were detected mostly during night time during both summer and winter. The results show an acoustic habitat dominated by biological sound sources and highlight the importance of the island to humpback whales in winter.
Li, W; Procter-Gray, E; Churchill, L; Crouter, S E; Kane, K; Tian, J; Franklin, P D; Ockene, J K; Gurwitz, J
2017-01-01
A thorough understanding of gender differences in physical activity is critical to effective promotion of active living in older adults. To examine gender and age differences in levels, types and locations of physical activity. Cross-sectional observation. Car-dependent urban and rural neighborhoods in Worcester County, Massachusetts, USA. 111 men and 103 women aged 65 years and older. From 2012 to 2014, participants were queried on type, frequency and location of physical activity. Participants wore an accelerometer for 7 consecutive days. Compared to women, men had a higher mean daily step count (mean (SD) 4385 (2122) men vs. 3671(1723) women, p=0.008). Men reported higher frequencies of any physical activity and moderate-to-vigorous physical activity, and a lower frequency of physical activity inside the home. Mean daily step counts and frequency of physical activity outside the home decreased progressively with age for both men and women. Women had a sharper decline in frequencies of self-reported physical activity. Men had a significant decrease in utilitarian walking, which women did not (p=0.07). Among participants who reported participation in any physical activity (n=190), more women indicated exercising indoors more often (59% vs. 44%, p=0.04). The three most commonly cited locations for physical activity away from home for both genders were streets or sidewalks, shopping malls, and membership-only facilities (e.g., YMCA or YWCA). The most common types of physical activity, performed at least once in a typical month, with over 40% of both genders reporting, included light housework, brisk walking, leisurely walking, and stretching. Levels, types and location preferences of physical activity differed substantially by gender. Levels of physical activity decreased progressively with age, with greater decline among women. Consideration of these gender differences is necessary to improve the effectiveness of active living promotion programs among older adults.
Magnus, Maria C; Stene, Lars C; Håberg, Siri E; Nafstad, Per; Stigum, Hein; London, Stephanie J; Nystad, Wenche
2013-11-01
Studies suggest that prenatal vitamin D status may be inversely associated with lower respiratory tract infections (LRTIs) early in life. Studies of prenatal vitamin D status and development of asthma have inconsistent findings. We examined the associations of maternal mid-pregnancy 25-hydroxyvitamin D [25(OH)D] level with the frequency of LRTIs by 36 months and with current asthma at 36 months using the Norwegian Mother and Child Cohort Study. Maternal plasma 25(OH)D level was measured using liquid chromatography-tandem mass spectrometry. Respiratory disorders were evaluated by maternal report through questionnaires. LRTIs were analysed in a random sample of 1248 children. Asthma was analysed using a case-control design, including 489 cases and 1183 controls. Multivariable generalised linear models calculated adjusted measures of association. The median gestational week of sample collection was 18 weeks (range 9, 35). The mean 25(OH)D level was 73.7 nmol/L (standard deviation 23.7). Higher maternal mid-pregnancy 25(OH)D level was associated with a reduced risk of three or more LRTIs by 36 months vs. none, adjusted risk ratio 0.74 [95% confidence interval (CI): 0.58, 0.93] per 20 nmol/L increase. Associations were similar when examining the frequency of LRTIs by 18 months, and the frequency of LRTIs between 18 and 36 months. Maternal mid-pregnancy 25(OH)D level was not significantly associated with current asthma at 36 months, adjusted odds ratio 0.91 [95% CI 0.81, 1.02] per 20 nmol/L increase. Higher maternal mid-pregnancy 25(OH)D level was associated with a modestly reduced risk of recurrent LRTIs by 36 months, but was not associated with current asthma at 36 months. © 2013 John Wiley & Sons Ltd.
Association of hair dye use with circulating levels of sex hormones in premenopausal Japanese women.
Nagata, Chisato; Wada, Keiko; Tsuji, Michiko; Hayashi, Makoto; Takeda, Noriyuki; Yasuda, Keigo
2015-10-01
Substances identified as animal carcinogens are no longer used as ingredients of hair dyes. However, hair dyes are diverse groups of chemicals, and certain compounds may affect endogenous sex hormone levels. We examined the association between hair dye use and sex hormone levels among premenopausal women. Study subjects were 431 premenopausal Japanese women who had regular menstrual cycles less than 40 days long. Information on the use of hair dyes or hair bleach, the type of hair coloring used, the duration of use and the frequency of application was collected using a self-administered questionnaire. Fasting plasma samples were obtained to measure estradiol, testosterone, dehydroepiandrosterone sulfate, sex hormone-binding globulin, follicle-stimulating hormone and luteinizing hormone. After controlling for covariates, the mean plasma total testosterone level was about 14% higher in women who had used hair dyes for 10 or more years than that among women who had never used them (P for trend = 0.02). A similar association was observed when the type of hair dye was restricted to permanent hair dyes. A higher frequency of applying non-permanent hair dyes was marginally significantly associated with higher total and free estradiol levels. Data suggest that long-term use of hair dyes may be associated with an increase in circulating testosterone levels. As this is, to our knowledge, the first study examining the association between hair dye use and sex hormone levels, replication of the results is required. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
2010-11-01
method at a fraction of the computational cost . The overtone frequency serves as the bridge between the molecule-surface interaction model and...the computational cost of utilizing higher levels of theory such as MP2. The second task is the calculation of absorption frequencies as a function...the methyl C-H bonds, and n\\ and inn are the carbon and hydrogen atomic masses, respectively. The calculation of the fundamental and overtone
NASA Astrophysics Data System (ADS)
Zhao, Yan; Li, DongXu; Liu, ZhiZhen; Liu, Liang
2013-03-01
The dexterous upper limb serves as the most important tool for astronauts to implement in-orbit experiments and operations. This study developed a simulated weightlessness experiment and invented new measuring equipment to quantitatively evaluate the muscle ability of the upper limb. Isometric maximum voluntary contractions (MVCs) and surface electromyography (sEMG) signals of right-handed pushing at the three positions were measured for eleven subjects. In order to enhance the comprehensiveness and accuracy of muscle force assessment, the study focused on signal processing techniques. We applied a combination method, which consists of time-, frequency-, and bi-frequency-domain analyses. Time- and frequency-domain analyses estimated the root mean square (RMS) and median frequency (MDF) of sEMG signals, respectively. Higher order spectra (HOS) of bi-frequency domain evaluated the maximum bispectrum amplitude ( B max), Gaussianity level (Sg) and linearity level (S l ) of sEMG signals. Results showed that B max, S l , and RMS values all increased as force increased. MDF and Sg values both declined as force increased. The research demonstrated that the combination method is superior to the conventional time- and frequency-domain analyses. The method not only described sEMG signal amplitude and power spectrum, but also deeper characterized phase coupling information and non-Gaussianity and non-linearity levels of sEMG, compared to two conventional analyses. The finding from the study can aid ergonomist to estimate astronaut muscle performance, so as to optimize in-orbit operation efficacy and minimize musculoskeletal injuries.
Górecka-Bruzda, Aleksandra; Fureix, Carole; Ouvrard, Anne; Bourjade, Marie; Hausberger, Martine
2016-10-01
Yawning is rare in herbivores which therefore may be an interesting group to disentangle the potential function(s) of yawning behaviour. Horses provide the opportunity to compare not only animals living in different conditions but also wild versus domestic species. Here, we tested three hypotheses by observing both domestic and Przewalski horses living in semi-natural conditions: (i) that domestic horses may show an elevated rate of yawning as a result of the domestication process (or as a result of life conditions), (ii) that individuals experiencing a higher level of social stress would yawn more than individuals with lower social stress and (iii) that males would yawn more often than females. The study involved 19 Przewalski horses (PHs) and 16 domestic horses (DHs) of different breeds living in large outdoor enclosures. The results showed that there was no difference between the PH and DH in yawning frequency (YF). PHs exhibited much higher levels of social interactions than DHs. There was a positive correlation between yawning frequency and aggressive behaviours in PHs, especially males, supporting the idea that yawning may be associated with more excitatory/stressful social situations. A correlation was found between yawning frequency and affiliative behaviours in DHs, which supports the potential relationship between yawning and social context. Finally, the entire males, but not castrated males, showed much higher levels of yawning than females in both species. The intensity (rather than the valence) of the interaction may be important in triggering yawning, which could therefore be a displacement activity that helps reduce tension.
NASA Astrophysics Data System (ADS)
Górecka-Bruzda, Aleksandra; Fureix, Carole; Ouvrard, Anne; Bourjade, Marie; Hausberger, Martine
2016-10-01
Yawning is rare in herbivores which therefore may be an interesting group to disentangle the potential function(s) of yawning behaviour. Horses provide the opportunity to compare not only animals living in different conditions but also wild versus domestic species. Here, we tested three hypotheses by observing both domestic and Przewalski horses living in semi-natural conditions: (i) that domestic horses may show an elevated rate of yawning as a result of the domestication process (or as a result of life conditions), (ii) that individuals experiencing a higher level of social stress would yawn more than individuals with lower social stress and (iii) that males would yawn more often than females. The study involved 19 Przewalski horses (PHs) and 16 domestic horses (DHs) of different breeds living in large outdoor enclosures. The results showed that there was no difference between the PH and DH in yawning frequency (YF). PHs exhibited much higher levels of social interactions than DHs. There was a positive correlation between yawning frequency and aggressive behaviours in PHs, especially males, supporting the idea that yawning may be associated with more excitatory/stressful social situations. A correlation was found between yawning frequency and affiliative behaviours in DHs, which supports the potential relationship between yawning and social context. Finally, the entire males, but not castrated males, showed much higher levels of yawning than females in both species. The intensity (rather than the valence) of the interaction may be important in triggering yawning, which could therefore be a displacement activity that helps reduce tension.
Frequency of high blood glucose prior to FDG PET.
Khandani, Amir H; Bravo, Isabel M; Patel, Parth S; Ivanovic, Marijana; Kirk, Deepa
2017-05-01
To assess the frequency of blood glucose level higher than 150 mg/dL in non-diabetic patients presenting for FDG PET. We reviewed the electronic medical record (EMR) of all lymphoma patients who had at least one FDG PET/CT from July 1, 2014 through June 30, 2015. We extracted the blood glucose level at the time of the FDG PET during this 1-year time period and any previous PET scans these patients had. Patients' diabetic status was determined from EMR. One hundred seventeen patients with 574 scans were included: 91 non-diabetic with 429 scans and 26 diabetic patients with 145 scans. Blood glucose level ranged from 44 to 259 mg/dL: 44 to 144 mg/dL in non-diabetic patients and 73 to 259 mg/dL in diabetic patients. There was no non-diabetic patient with a glucose level higher than 150 mg/dL at any occasion. Only one scan was performed with 144 mg/dL of glucose. All other scans were performed with a glucose level less than 140 mg/dL. There were nine diabetic patients with glucose level less than 150 mg/dL prior to all of their scans and 17 diabetic patients with a glucose level higher than 150 mg/dL prior to PET at least on one occasion. In all non-diabetic patients, blood glucose level was below the lower limit of the recommended range prior to all their FDG PET scans while this was not the case in diabetic patients. We conclude that measuring blood glucose level prior to FDG PET may be limited to diabetic patients.
On the Horn Effect of a Tyre/road Interface, Part i: Experiment and Computation
NASA Astrophysics Data System (ADS)
Graf, R. A. G.; Kuo, C.-Y.; Dowling, A. P.; Graham, W. R.
2002-09-01
Near the tyre/road contact area, the road surface and the tyre belt form a horn-like geometry, which provides a significant amplification mechanism for sound sources. Measurements have been carried out on a stationary tyre placed on a plane surface in an otherwise anechoic chamber. Following the reciprocal theorem a microphone was placed in the road surface near the contact patch and a white noise source was used in the far field. The amplification by the horn effect can then be determined as a function of frequency for an array of microphone positions relative to the contact patch and the centre of the tyre. These experimental measurements show that the horn effect is responsible for about 10-20dB increase in noise level. The amplification function shows a distinct interference pattern for higher frequencies and is independent of the longitudinal source position for low frequencies and source positions close to the contact patch. Numerical calculations using the indirect boundary element method have been carried out. These show excellent agreement with the measurements in the frequency regime of the BEM, i.e., up to 2500 Hz. The dependence of the horn effect on primary geometrical parameters such as the effect of the radius of curvature of the shoulders, the load and the width of the tyre has been investigated experimentally and numerically. The broad features of the horn effect are given by the cylindrical geometry of the tyre. The rounded edges of the tyre tend to increase the levels of the minima and shift them to higher frequencies, while slightly decreasing the levels of the maxima. Shape variations due to load can be accounted for by correcting the source distance to the edge of the formed contact patch. The amplification at low frequencies increases with width, the results collapsing onto a single curve as a function of the dimensionless width ω / λ.
Measurements of Free-Space Oscillating Pressures Near Propellers at Flight Mach Numbers to 0.72
NASA Technical Reports Server (NTRS)
Kurbjun, Max C; Vogeley, Arthur W
1958-01-01
In the course of a short flight program initiated to check the theory of Garrick and Watkins (NACA rep. 1198), a series of measurements at three stations were made of the oscillating pressures near a tapered-blade plan-form propeller and rectangular-blade plan form propeller at flight Mach numbers up to 0.72. In contradiction to the results for the propeller studied in NACA rep. 1198, the oscillating pressures in the plane ahead of the propeller were found to be higher than those immediately behind the propeller. Factors such as variation in torque and thrust distribution, since the blades of the present investigation were operating above their design forward speed, may account for this contradiction. The effect of blade plan form shows that a tapered-blade plan-form propeller will produce lower sound-pressure levels than a rectangular-blade plan-form propeller for the low blade-passage harmonics (the frequencies where structural considerations are important) and produce higher sound-pressure levels for the higher blade-passage harmonics (frequencies where passenger comfort is important).
Estimating the vibration level of an L-shaped beam using power flow techniques
NASA Technical Reports Server (NTRS)
Cuschieri, J. M.; Mccollum, M.; Rassineux, J. L.; Gilbert, T.
1986-01-01
The response of one component of an L-shaped beam, with point force excitation on the other component, is estimated using the power flow method. The transmitted power from the source component to the receiver component is expressed in terms of the transfer and input mobilities at the excitation point and the joint. The response is estimated both in narrow frequency bands, using the exact geometry of the beams, and as a frequency averaged response using infinite beam models. The results using this power flow technique are compared to the results obtained using finite element analysis (FEA) of the L-shaped beam for the low frequency response and to results obtained using statistical energy analysis (SEA) for the high frequencies. The agreement between the FEA results and the power flow method results at low frequencies is very good. SEA results are in terms of frequency averaged levels and these are in perfect agreement with the results obtained using the infinite beam models in the power flow method. The narrow frequency band results from the power flow method also converge to the SEA results at high frequencies. The advantage of the power flow method is that detail of the response can be retained while reducing computation time, which will allow the narrow frequency band analysis of the response to be extended to higher frequencies.
Bermúdez-Cuamatzin, Eira; Ríos-Chelén, Alejandro A; Gil, Diego; Garcia, Constantino Macías
2011-02-23
Research has shown that bird songs are modified in different ways to deal with urban noise and promote signal transmission through noisy environments. Urban noise is composed of low frequencies, thus the observation that songs have a higher minimum frequency in noisy places suggests this is a way of avoiding noise masking. Most studies are correlative and there is as yet little experimental evidence that this is a short-term mechanism owing to individual plasticity. Here we experimentally test if house finches (Carpodacus mexicanus) can modulate the minimum frequency of their songs in response to different noise levels. We exposed singing males to three continuous treatments: low-high-low noise levels. We found a significant increase in minimum frequency from low to high and a decrement from high to low treatments. We also found that this was mostly achieved by modifying the frequency of the same low-frequency syllable types used in the different treatments. When different low-frequency syllables were used, those sung during the noisy condition were longer than the ones sang during the quiet condition. We conclude that house finches modify their songs in several ways in response to urban noise, thus providing evidence of a short-term acoustic adaptation.
Kim, Hye-Suk
2005-10-01
The purpose of this study was to develop and to apply the NANDA, NOC, and NIC (NNN) linkages into a computerized nursing process program using the classification systems of nursing diagnoses, nursing outcomes and nursing interventions. The program was developed with planning, analysis, design and performance stages. The program was applied to 117 patients who were admitted to orthopedic surgery nursing units from January to February, 2004. Thirty-five of fifty-three nursing diagnoses were identified. Five nursing diagnoses in order of frequency were: Acute pain (28.4%), Impaired physical mobility (15.6%), Impaired walking (8.7%), Chronic pain (5.5%) and Risk for disuse syndrome (5.0%). The nursing outcomes of the 'Acute pain' nursing diagnosis tended to have higher frequencies (cumulative) in order of Pain management (95.2%), Comfort level (35.5%) and Pain level (17.7%). The nursing interventions of the 'Acute pain' nursing diagnosis tended to have higher frequencies (cumulative) in order of Pain management (71.0%), Splinting (24.2%) and Analgesic administration (17.7%). In comparison of outcome indicator scores between before and after the intervention according to the 61 nursing outcomes, the mean scores of 52 outcome indicators after the intervention were significantly higher than before the intervention. It is expected that this program will help nurses perform their nursing processes more efficiently.
Drinking behaviors by stress level in Korean university students.
Chung, Hye-Kyung; Lee, Hae-Young
2012-04-01
The purposes of this study are to estimate the stress level of university students, and to verify the relationships between stress level and drinking behavior. A questionnaire survey was administered to 430 university students in the Gangwon area in Korea from November 5 to November 28, 2008, and data from 391 students were used for the final statistical analysis. The most stressful factor was "Worry about academic achievements" (2.86 by Likert-type 4 point scale). The subjects were divided into two groups, a low stress group (≤ 65.0) and a high stress group (≥ 66.0), by the mean value (65.1) and median value (66.0) of the stress levels. The drinking frequency was not different between the two stress groups, but the amount of alcohol consumption was significantly different (P < 0.05). The portion of students reporting drinking "7 glasses or over" was higher in the lower stress group than in the higher stress group. In addition, factor 6, "Lack of learning ability", was negatively correlated with drinking frequency and the amount of alcohol consumption (P < 0.05), and factor 3, "Worry about academic achievements", was negatively correlated with the amount of drinking (P < 0.05). The major motive for drinking was "When overjoyed or there is something to celebrate" (2.62), and the main expected effect of drinking was "Drinking enables me to get together with people and shape my sociability" (2.73). The higher stress group showed significantly higher scores on several items in the categories of motives (P < 0.01), negative experience (P < 0.05), and expected effects (P < 0.05) of drinking than the lower stress group. Our results imply that university students at the lower stress level may drink more from social motives in positive drinking environments, while those at the higher stress level may have more problematic-drinking despite their smaller amount of alcohol consumption.
Validation of Pooled Whole-Genome Re-Sequencing in Arabidopsis lyrata.
Fracassetti, Marco; Griffin, Philippa C; Willi, Yvonne
2015-01-01
Sequencing pooled DNA of multiple individuals from a population instead of sequencing individuals separately has become popular due to its cost-effectiveness and simple wet-lab protocol, although some criticism of this approach remains. Here we validated a protocol for pooled whole-genome re-sequencing (Pool-seq) of Arabidopsis lyrata libraries prepared with low amounts of DNA (1.6 ng per individual). The validation was based on comparing single nucleotide polymorphism (SNP) frequencies obtained by pooling with those obtained by individual-based Genotyping By Sequencing (GBS). Furthermore, we investigated the effect of sample number, sequencing depth per individual and variant caller on population SNP frequency estimates. For Pool-seq data, we compared frequency estimates from two SNP callers, VarScan and Snape; the former employs a frequentist SNP calling approach while the latter uses a Bayesian approach. Results revealed concordance correlation coefficients well above 0.8, confirming that Pool-seq is a valid method for acquiring population-level SNP frequency data. Higher accuracy was achieved by pooling more samples (25 compared to 14) and working with higher sequencing depth (4.1× per individual compared to 1.4× per individual), which increased the concordance correlation coefficient to 0.955. The Bayesian-based SNP caller produced somewhat higher concordance correlation coefficients, particularly at low sequencing depth. We recommend pooling at least 25 individuals combined with sequencing at a depth of 100× to produce satisfactory frequency estimates for common SNPs (minor allele frequency above 0.05).
Influence of sex, estrous cycle and estrogen on intracranial dural mast cells
Boes, Tanner; Levy, Dan
2014-01-01
Background The frequency of migraine headaches is higher in women than in men and in susceptible women attacks are related to changes in ovarian hormone levels. Intracranial mast cells (MCs) are likely to play a role in migraine headache genesis, and changes in the dural MC population might influence headache susceptibility. The present study thus tested the hypothesis that sex and ovarian hormones influence the density and phenotypic makeup of dural MCs. Methods Histochemistry combined with quantitative analyses was employed to investigate sex differences, estrous cycle and ovarian hormone influences on dural MCs density, phenotype and degranulation level in males and females rats. Results Our data show that in female rats, dural MC density fluctuates during the estrous cycle and is overall higher than in males. In ovariectomized rats, estradiol, but not progesterone, promoted an increase in dural MCs density. This effect was abolished by a splenectomy, suggesting estrogen-related recruitment of MCs from the spleen. Finally, our data suggest that the phenotypic make up of dural MCs, which represents the level of cellular maturity, is also governed by changes in estrogen levels. Conclusions Given the potential role of dural MCs in triggering headache, our data suggest that estrogen-related modulation of dural MC density and phenotypic makeup could play a role in mediating the higher frequency and severity of headaches, such as migraine, in women. PMID:22833613
Romero-Moreno, Rosa; Losada, Andrés; Marquez, María; Laidlaw, Ken; Fernández-Fernández, Virginia; Nogales-González, Celia; López, Javier
2014-07-01
The moderator role of guilt on the effect of leisure activities on dementia caregivers' depressive symptoms was analyzed, considering differences by kinship and guilt as a multidimensional construct. Participants were 351 caregivers (58.97% daughters, 10.54% sons, 19.66% wives, and 10.83% husbands). Measures included frequency of leisure activities, depressive symptoms, and guilt (total scale and 5 factors). A moderator role of guilt was found only for daughters. Specifically, significant interactions between guilt and frequency of leisure activities were found for the total scale and for the Factors 1 (guilt about doing wrong by the care recipient), 2 (guilt about failing to meet the challenges of caregiving), and 3 (guilt about self-care). For those daughters who reported lower levels of leisure activities, showing higher levels of guilt was associated with higher scores in depressive symptoms, whereas those with lower levels of guilt showed lower depressive symptoms scores. Feelings of guilt may have different consequences on caregivers' distress depending on caregivers' gender and kinship. Daughters with higher levels of guilt who do not engage in leisure activities may be especially vulnerable to suffering psychological distress. © The Author 2013. 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.
Large Civil Tiltrotor (LCTR2) Interior Noise Predictions due to Turbulent Boundary Layer Excitation
NASA Technical Reports Server (NTRS)
Grosveld, Ferdinand W.
2013-01-01
The Large Civil Tiltrotor (LCTR2) is a conceptual vehicle that has a design goal to transport 90 passengers over a distance of 1800 km at a speed of 556 km/hr. In this study noise predictions were made in the notional LCTR2 cabin due to Cockburn/Robertson and Efimtsov turbulent boundary layer (TBL) excitation models. A narrowband hybrid Finite Element (FE) analysis was performed for the low frequencies (6-141 Hz) and a Statistical Energy Analysis (SEA) was conducted for the high frequency one-third octave bands (125- 8000 Hz). It is shown that the interior sound pressure level distribution in the low frequencies is governed by interactions between individual structural and acoustic modes. The spatially averaged predicted interior sound pressure levels for the low frequency hybrid FE and the high frequency SEA analyses, due to the Efimtsov turbulent boundary layer excitation, were within 1 dB in the common 125 Hz one-third octave band. The averaged interior noise levels for the LCTR2 cabin were predicted lower than the levels in a comparable Bombardier Q400 aircraft cabin during cruise flight due to the higher cruise altitude and lower Mach number of the LCTR2. LCTR2 cabin noise due to TBL excitation during cruise flight was found not unacceptable for crew or passengers when predictions were compared to an acoustic survey on a Q400 aircraft.
Suppression of thermal frequency noise in erbium-doped fiber random lasers.
Saxena, Bhavaye; Bao, Xiaoyi; Chen, Liang
2014-02-15
Frequency and intensity noise are characterized for erbium-doped fiber (EDF) random lasers based on Rayleigh distributed feedback mechanism. We propose a theoretical model for the frequency noise of such random lasers using the property of random phase modulations from multiple scattering points in ultralong fibers. We find that the Rayleigh feedback suppresses the noise at higher frequencies by introducing a Lorentzian envelope over the thermal frequency noise of a long fiber cavity. The theoretical model and measured frequency noise agree quantitatively with two fitting parameters. The random laser exhibits a noise level of 6 Hz²/Hz at 2 kHz, which is lower than what is found in conventional narrow-linewidth EDF fiber lasers and nonplanar ring laser oscillators (NPROs) by a factor of 166 and 2, respectively. The frequency noise has a minimum value for an optimum length of the Rayleigh scattering fiber.
Physiological stimuli evoke two forms of endocytosis in bovine chromaffin cells.
Chan, S A; Smith, C
2001-12-15
1. Exocytosis and endocytosis were measured following single, or trains of, simulated action potentials (sAP) in bovine adrenal chromaffin cells. Catecholamine secretion was measured by oxidative amperometry and cell membrane turnover was measured by voltage clamp cell capacitance measurements. 2. The sAPs evoked inward Na(+) and Ca(2+) currents that were statistically identical to those evoked by native action potential waveforms. On average, a single secretory granule underwent fusion following sAP stimulation. An equivalent amount of membrane was then quickly internalised (tau = 560 ms). 3. Stimulation with sAP trains revealed a biphasic relationship between cell firing rate and endocytic activity. At basal stimulus frequencies (single to 0.5 Hz) cells exhibited a robust membrane internalisation that then diminished as firing increased to intermediate levels (1.9 and 6 Hz). However at the higher stimulation rates (10 and 16 Hz) endocytic activity rebounded and was again able to effectively maintain cell surface near pre-stimulus levels. 4. Treatment with cyclosporin A and FK506, inhibitors of the phosphatase calcineurin, left endocytosis characteristics unaltered at the lower basal stimulus levels, but blocked the resurgence in endocytosis seen in control cells at higher sAP frequencies. 5. Based on these findings we propose that, under physiological electrical stimulation, chromaffin cells internalise membrane via two distinct pathways that are separable. One is prevalent at basal stimulus frequencies, is lessened with increased firing, and is insensitive to cyclosporin A and FK506. A second endocytic form is activated by increased firing frequencies, and is selectively blocked by cyclosporin A and FK506.
Physiological stimuli evoke two forms of endocytosis in bovine chromaffin cells
Chan, Shyue-An; Smith, Corey
2001-01-01
Exocytosis and endocytosis were measured following single, or trains of, simulated action potentials (sAP) in bovine adrenal chromaffin cells. Catecholamine secretion was measured by oxidative amperometry and cell membrane turnover was measured by voltage clamp cell capacitance measurements. The sAPs evoked inward Na+ and Ca2+ currents that were statistically identical to those evoked by native action potential waveforms. On average, a single secretory granule underwent fusion following sAP stimulation. An equivalent amount of membrane was then quickly internalised (τ = 560 ms). Stimulation with sAP trains revealed a biphasic relationship between cell firing rate and endocytic activity. At basal stimulus frequencies (single to 0.5 Hz) cells exhibited a robust membrane internalisation that then diminished as firing increased to intermediate levels (1.9 and 6 Hz). However at the higher stimulation rates (10 and 16 Hz) endocytic activity rebounded and was again able to effectively maintain cell surface near pre-stimulus levels. Treatment with cyclosporin A and FK506, inhibitors of the phosphatase calcineurin, left endocytosis characteristics unaltered at the lower basal stimulus levels, but blocked the resurgence in endocytosis seen in control cells at higher sAP frequencies. Based on these findings we propose that, under physiological electrical stimulation, chromaffin cells internalise membrane via two distinct pathways that are separable. One is prevalent at basal stimulus frequencies, is lessened with increased firing, and is insensitive to cyclosporin A and FK506. A second endocytic form is activated by increased firing frequencies, and is selectively blocked by cyclosporin A and FK506. PMID:11744761
Origin of the bell-like dependence of the DPOAE amplitude on primary frequency ratio
NASA Astrophysics Data System (ADS)
Lukashkin, Andrei N.; Russell, Ian J.
2001-12-01
For low and medium sound pressure levels (SPLs), the amplitude of the distortion product otoacoustic emission (DPOAE) recorded from guinea pigs at the 2f1-f2 frequency is maximal when f2/f1~1.23 and decreases for lower and higher f2/f1 ratios. The high-ratio slope of the DPOAE dependence on the ratio of the primary frequencies might be anticipated since the f1 amplitude at the f2 place is expected to decrease for higher f2/f1 ratios. The low-ratio slope of the dependence at low and medium SPLs of the primaries is actually one slope of a notch. The DPOAE amplitude recovers from the notch when the f2/f1 ratio is further reduced. In two-dimensional space formed by the f2/f1 ratio, and the levels of the primaries, the notch is continuous and has a level-dependent phase transition. The notch is identical to that seen in DPOAE growth functions. Similar notches and phase transitions were observed for high-order and high-frequency DPOAEs. Theoretical analysis reveals that a single saturating nonlinearity is capable of generating similar amplitude notch and phase transition when the f2/f1 ratio is decreased because of the increase in f1 amplitude at the DPOAE generation place (f2 place). The difference between the DPOAE recorded from guinea pigs and humans is discussed in terms of different position of the operating point of the DPOAE generating nonlinearity.
Thomas, Silke; Kühnlein, Anja; Heinrich, Sabine; Praml, Georg; von Kries, Rüdiger; Radon, Katja
2008-11-04
Despite the increase of mobile phone use in the last decade and the growing concern whether mobile telecommunication networks adversely affect health and well-being, only few studies have been published that focussed on children and adolescents. Especially children and adolescents are important in the discussion of adverse health effects because of their possibly higher vulnerability to radio frequency electromagnetic fields. We investigated a possible association between exposure to mobile telecommunication networks and well-being in children and adolescents using personal dosimetry. A population-based sample of 1.498 children and 1.524 adolescents was assembled for the study (response 52%). Participants were randomly selected from the population registries of four Bavarian (South of Germany) cities and towns with different population sizes. During a Computer Assisted Personal Interview data on participants' well-being, socio-demographic characteristics and potential confounder were collected. Acute symptoms were assessed three times during the study day (morning, noon, evening).Using a dosimeter (ESM-140 Maschek Electronics), we obtained an exposure profile over 24 hours for three mobile phone frequency ranges (measurement interval 1 second, limit of determination 0.05 V/m) for each of the participants. Exposure levels over waking hours were summed up and expressed as mean percentage of the ICNIRP (International Commission on Non-Ionizing Radiation Protection) reference level. In comparison to non-participants, parents and adolescents with a higher level of education who possessed a mobile phone and were interested in the topic of possible adverse health effects caused by mobile telecommunication network frequencies were more willing to participate in the study. The median exposure to radio frequency electromagnetic fields of children and adolescents was 0.18% and 0.19% of the ICNIRP reference level respectively. In comparison to previous studies this is one of the first to assess the individual level of exposure to mobile telecommunication networks using personal dosimetry, enabling objective assessment of exposure from all sources and longer measurement periods. In total, personal dosimetry was proofed to be a well accepted tool to study exposure to mobile phone frequencies in epidemiologic studies including health effects on children and adolescents.
Immediate spectral flexibility in singing chiffchaffs during experimental exposure to highway noise.
Verzijden, M N; Ripmeester, E A P; Ohms, V R; Snelderwaard, P; Slabbekoorn, H
2010-08-01
Sound plays an important role in the life of many animals, including many bird species. Typically, male birds sing to defend a territory and to attract mates. Ambient noise may negatively affect the signal efficiency of their songs, which may be critical to reproductive success. Consequently, anthropogenic noise may be detrimental to individual birds and to populations in cities and along highways. Several bird species that are still common in urban areas have been shown to sing at higher frequency at locations where there is more low-frequency traffic noise. Here we show that chiffchaffs along noisy highways also sing with a higher minimum frequency than chiffchaffs nearby at a quiet riverside. Furthermore, through experimental exposure to highway noise we show that these birds are capable of making such adjustments over a very short time scale. The first 10 songs sung during the noise exposure revealed an immediate shift to higher frequencies, with a return to pre-exposure levels in recordings without noise the following day. In a transmission re-recording experiment we tested the impact of a potential measurement artifact by recording playback of the same songs repeatedly under different controlled noise conditions. We found an upward shift in the minimum frequency measurement associated with more noisy recordings of the same song, but this artifact was not of a scale that it could explain the noise-dependent spectral shifts in chiffchaffs.
Discrimination of rippled-spectrum patterns in noise: A manifestation of compressive nonlinearity
Milekhina, Olga N.; Nechaev, Dmitry I.; Klishin, Vladimir O.
2017-01-01
In normal-hearing listeners, rippled-spectrum discrimination was psychophysically investigated in both silence and with a simultaneous masker background using the following two paradigms: measuring the ripple density resolution with the phase-reversal test and measuring the ripple-shift threshold with the ripple-shift test. The 0.5-oct wide signal was centered on 2 kHz, the signal levels were 50 and 80 dB SPL, and the masker levels varied from 30 to 100 dB SPL. The baseline ripple density resolutions were 8.7 oct-1 and 8.6 oct-1 for the 50-dB and 80-dB signals, respectively. The baseline ripple shift thresholds were 0.015 oct and 0.018 oct for the 50-dB and 80-dB signals, respectively. The maskers were 0.5-oct noises centered on 2 kHz (on-frequency) or 0.75 to 1.25 oct below the signal (off-frequency maskers). The effects of the maskers were as follows: (i) both on- and low-frequency maskers reduced the ripple density resolution and increased the ripple shift thresholds, (ii) the masker levels at threshold (the ripple density resolution decrease down to 3 oct–1 or ripple shift threshold increased up to 0.1 oct) increased with increasing frequency spacing between the signal and masker, (iii) the masker levels at threshold were higher for the 80-dB signal than for the 50-dB signal, and (iv) the difference between the masker levels at threshold for the 50-dB and 80-dB signals decreased with increasing frequency spacing between the masker and signal. Within the 30-dB (from 50 to 80 dB SPL) signal level, the growth of the masker level at threshold was 27.8 dB for the on-frequency masker and 9 dB for the low-frequency masker. It is assumed that the difference between the on- and low-frequency masking of the rippled-spectrum discrimination reflects the cochlear compressive non-linearity. With this assumption, the compression was 0.3 dB/dB. PMID:28346538
NASA Astrophysics Data System (ADS)
Lan, Chunbo; Tang, Lihua; Qin, Weiyang
2017-07-01
Nonlinear energy harvesters have attracted wide research attentions to achieve broadband performances in recent years. Nonlinear structures have multiple solutions in certain frequency region that contains high-energy and low-energy orbits. It is effectively the frequency region of capturing a high-energy orbit that determines the broadband performance. Thus, maintaining large-amplitude high-energy-orbit oscillations is highly desired. In this paper, a voltage impulse perturbation approach based on negative resistance is applied to trigger high-energy-orbit responses of piezoelectric nonlinear energy harvesters. First, the mechanism of the voltage impulse perturbation and the implementation of the synthetic negative resistance circuit are discussed in detail. Subsequently, numerical simulation and experiment are conducted and the results demonstrate that the high-energy-orbit oscillations can be triggered by the voltage impulse perturbation method for both monostable and bistable configurations given various scenarios. It is revealed that the perturbation levels required to trigger and maintain high-energy-orbit oscillations are different for various excitation frequencies in the region where multiple solutions exist. The higher gain in voltage output when high-energy-orbit oscillations are captured is accompanied with the demand of a higher voltage impulse perturbation level.
Berenbaum, Howard; Okazaki, Sumie
2012-01-01
The current study examined perceptions of living up to parental expectations and personal standards as possible mediators of the relationship between ethnicity and worry in a sample of 836 Asian American and 856 White American college students. Asian Americans reported higher frequency of academic- and family-related worry, but they did not report higher levels of global tendency to worry. Perceptions of living up to parental expectations of current academic performance and personal standards for preparation for a future career partially explained ethnic differences in frequency of academic worry. Personal standards and perceptions of living up to parental expectations for respect for the family partially explained ethnic differences in frequency of family worry. The findings highlight the importance of targeting domain-specific personal standards and perceived parental expectations to reduce worry among Asian Americans. PMID:22416875
Madsen, P T; Johnson, M; Miller, P J O; Aguilar Soto, N; Lynch, J; Tyack, P
2006-10-01
The widespread use of powerful, low-frequency air-gun pulses for seismic seabed exploration has raised concern about their potential negative effects on marine wildlife. Here, we quantify the sound exposure levels recorded on acoustic tags attached to eight sperm whales at ranges between 1.4 and 12.6 km from controlled air-gun array sources operated in the Gulf of Mexico. Due to multipath propagation, the animals were exposed to multiple sound pulses during each firing of the array with received levels of analyzed pulses falling between 131-167 dB re. 1 microPa (pp) [111-147 dB re. 1 microPa (rms) and 100-135 dB re. 1 microPa2 s] after compensation for hearing sensitivity using the M-weighting. Received levels varied widely with range and depth of the exposed animal precluding reliable estimation of exposure zones based on simple geometric spreading laws. When whales were close to the surface, the first arrivals of air-gun pulses contained most energy between 0.3 and 3 kHz, a frequency range well beyond the normal frequencies of interest in seismic exploration. Therefore air-gun arrays can generate significant sound energy at frequencies many octaves higher than the frequencies of interest for seismic exploration, which increases concern of the potential impact on odontocetes with poor low frequency hearing.
Riffel, Philipp; Haubenreisser, Holger; Meyer, Mathias; Sudarski, Sonja; Morelli, John N; Schmidt, Bernhard; Schoenberg, Stefan O; Henzler, Thomas
2016-04-01
Calculated monoenergetic ultra-low keV datasets did not lead to improved contrast-to-noise ratio (CNR) due to the dramatic increase in image noise. The aim of the present study was to evaluate the objective image quality of ultra-low keV monoenergetic images (MEIs) calculated from carotid DECT angiography data with a new monoenergetic imaging algorithm using a frequency-split technique. 20 patients (12 male; mean age 53±17 years) were retrospectively analyzed. MEIs from 40 to 120 keV were reconstructed using the monoenergetic split frequency approach (MFSA). Additionally MEIs were reconstructed for 40 and 50 keV using a conventional monoenergetic (CM) software application. Signal intensity, noise, signal-to-noise ratio (SNR) and CNR were assessed in the basilar, common, internal carotid arteries. Ultra-low keV MEIs at 40 keV and 50 keV demonstrated highest vessel attenuation, significantly greater than those of the polyenergetic images (PEI) (all p-values <0.05). The highest SNR level and CNR level was found at 40 keV and 50 keV (all p-values <0.05). MEIs with MFSA showed significantly lower noise levels than those processed with CM (all p-values <0.05) and no significant differences in vessel attenuation (p>0.05). Thus MEIs with MFSA showed significantly higher SNR and CNR compared to MEIs with CM. Combining the lower spatial frequency stack for contrast at low keV levels with the high spatial frequency stack for noise at high keV levels (frequency-split technique) leads to improved image quality of ultra-low keV monoenergetic DECT datasets when compared to previous monoenergetic reconstruction techniques without the frequency-split technique. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Monson, Brian B; Lotto, Andrew J; Story, Brad H
2012-09-01
The human singing and speech spectrum includes energy above 5 kHz. To begin an in-depth exploration of this high-frequency energy (HFE), a database of anechoic high-fidelity recordings of singers and talkers was created and analyzed. Third-octave band analysis from the long-term average spectra showed that production level (soft vs normal vs loud), production mode (singing vs speech), and phoneme (for voiceless fricatives) all significantly affected HFE characteristics. Specifically, increased production level caused an increase in absolute HFE level, but a decrease in relative HFE level. Singing exhibited higher levels of HFE than speech in the soft and normal conditions, but not in the loud condition. Third-octave band levels distinguished phoneme class of voiceless fricatives. Female HFE levels were significantly greater than male levels only above 11 kHz. This information is pertinent to various areas of acoustics, including vocal tract modeling, voice synthesis, augmentative hearing technology (hearing aids and cochlear implants), and training/therapy for singing and speech.
Talk aloud problem solving: Exploration of acquisition and frequency building in science text
NASA Astrophysics Data System (ADS)
Dembek, Ginny
Discovering new ways to help students attain higher levels of scientific knowledge and to think critically is a national goal (Educate to Innovate campaign). Despite the best intentions, many students struggle to achieve a basic level of science knowledge (NAEP, 2011). The present study examined Talk Aloud Pair Problem Solving and frequency building with five students who were diagnosed with a disability and receive specialized reading instruction in a special education setting. Acquisition was obtained through scripted lessons and frequency building or practice strengthened the student's verbal repertoire making the problem solving process a durable behavior. Overall, students all demonstrated improvements in problem solving performance when compared to baseline. Students became more significantly accurate in performance and maintenance in learning was demonstrated. Generalization probes indicated improvement in student performance. Implications for practice and future research are discussed.
Gockel, Hedwig E; Krugliak, Alexandra; Plack, Christopher J; Carlyon, Robert P
2015-12-01
The frequency following response (FFR) is a scalp-recorded measure of phase-locked brainstem activity to stimulus-related periodicities. Three experiments investigated the specificity of the FFR for carrier and modulation frequency using adaptation. FFR waveforms evoked by alternating-polarity stimuli were averaged for each polarity and added, to enhance envelope, or subtracted, to enhance temporal fine structure information. The first experiment investigated peristimulus adaptation of the FFR for pure and complex tones as a function of stimulus frequency and fundamental frequency (F0). It showed more adaptation of the FFR in response to sounds with higher frequencies or F0s than to sounds with lower frequency or F0s. The second experiment investigated tuning to modulation rate in the FFR. The FFR to a complex tone with a modulation rate of 213 Hz was not reduced more by an adaptor that had the same modulation rate than by an adaptor with a different modulation rate (90 or 504 Hz), thus providing no evidence that the FFR originates mainly from neurons that respond selectively to the modulation rate of the stimulus. The third experiment investigated tuning to audio frequency in the FFR using pure tones. An adaptor that had the same frequency as the target (213 or 504 Hz) did not generally reduce the FFR to the target more than an adaptor that differed in frequency (by 1.24 octaves). Thus, there was no evidence that the FFR originated mainly from neurons tuned to the frequency of the target. Instead, the results are consistent with the suggestion that the FFR for low-frequency pure tones at medium to high levels mainly originates from neurons tuned to higher frequencies. Implications for the use and interpretation of the FFR are discussed.
NASA Astrophysics Data System (ADS)
Lunkenheimer, P.; Mayr, F.; Loidl, A.
2006-07-01
We report the frequency-dependent conductivity of the manganite system La1-xSrxMnO3 (x0.2) when approaching the metal-insulator transition from the insulating side. Results from low-frequency dielectric measurements are combined with spectra in the infrared region. For low doping levels the behavior is dominated by hopping transport of localized charge carriers at low frequencies and by phononic and electronic excitations in the infrared region. For the higher Sr contents the approach of the metallic state is accompanied by the successive suppression of the hopping contribution at low frequencies and by the development of polaronic excitations in the infrared region, which finally become superimposed by a strong Drude contribution in the fully metallic state.
Off-resonance frequency operation for power transfer in a loosely coupled air core transformer
Scudiere, Matthew B
2012-11-13
A power transmission system includes a loosely coupled air core transformer having a resonance frequency determined by a product of inductance and capacitance of a primary circuit including a primary coil. A secondary circuit is configured to have a substantially same product of inductance and capacitance. A back EMF generating device (e.g., a battery), which generates a back EMF with power transfer, is attached to the secondary circuit. Once the load power of the back EMF generating device exceeds a certain threshold level, which depends on the system parameters, the power transfer can be achieved at higher transfer efficiency if performed at an operating frequency less than the resonance frequency, which can be from 50% to 95% of the resonance frequency.
Eini, Peyman; Shirvani, Maria; Hajilooi, Mehrdad; Esna-Ashari, Farzaneh
2018-02-12
The inflammatory response to Mycobacterium tuberculosis bacilli influences tuberculosis (TB) progression. In this study, we aimed to identify the Phe206Leu polymorphism and serum L-selectin level in TB patients, compared to healthy individuals. Ninety patients with a diagnosis of TB and 90 healthy controls were selected in this study. The serum L-selectin level was determined, using ELISA. L-selectin polymorphism was also evaluated using PCR. For data analysis, SPSS was used at a significance level of 0.05. According to the findings, the mean±SD age of the participants was 57.5 ± 18.4 and 56.5 ± 17.5 years in the TB and healthy groups, respectively. The TB group showed a significantly higher serum L-selectin level (1721.1 ± 330.9) versus the healthy controls (1624 ± 279). The L-selectin Phe allele frequencies were higher than the Leu allele frequencies in the main population, whereas the patients and controls were not significantly different. Eight (0.04%) subjects had Leu/Leu genotypes, 84 (46.6%) carried Phe/Leu genotypes, and 88 (48.8%) had Phe/Phe genotypes. Our results showed that the groups were not significantly different regarding L-selectin genotypes. TB patients had a significantly higher serum L-selectin level, compared to the controls. Based on the findings, the incidence of TB and L-selectin polymorphism in the Phe206Leu gene had no significant association. © 2018 Wiley Periodicals, Inc.
Digital Low Level RF Systems for Fermilab Main Ring and Tevatron
NASA Astrophysics Data System (ADS)
Chase, B.; Barnes, B.; Meisner, K.
1997-05-01
At Fermilab, a new Low Level RF system is successfully installed and operating in the Main Ring. Installation is proceeding for a Tevatron system. This upgrade replaces aging CAMAC/NIM components for an increase in accuracy, reliability, and flexibility. These VXI systems are based on a custom three channel direct digital synthesizer(DDS) module. Each synthesizer channel is capable of independent or ganged operation for both frequency and phase modulation. New frequency and phase values are computed at a 100kHz rate on the module's Analog Devices ADSP21062 (SHARC) digital signal processor. The DSP concurrently handles feedforward, feedback, and beam manipulations. Higher level state machines and the control system interface are handled at the crate level using the VxWorks operating system. This paper discusses the hardware, software and operational aspects of these LLRF systems.
Seaton, Eleanor K.; Upton, Rachel D.; Sellers, Robert M.; Neblett, Enrique W.; Hammond, Wizdom Powell
2011-01-01
The present study examined the influence of racial identity in the longitudinal relationship between perceptions of racial discrimination and psychological well-being for approximately 560 African American youth. Latent curve modeling (LCM) and parallel process multiple-indicator LCMs with latent moderators were used to assess whether perceptions of racial discrimination predicted the intercept (initial levels) and the slope (rate of change) of psychological well-being over time, and whether racial identity moderates these relationships. The results indicated that African American adolescents who reported higher psychological responses to discrimination frequency levels at the first time point had lower initial levels of well-being. Regressing the slope factor for psychological well-being on frequency of discrimination also revealed a non-significant result for subsequent well-being levels. PMID:21954919
Pairing in half-filled Landau level
NASA Astrophysics Data System (ADS)
Wang, Zhiqiang; Mandal, Ipsita; Chung, Suk Bum; Chakravarty, Sudip
2015-03-01
Pairing of composite fermions in half-filled Landau level state is reexamined by solving the BCS gap equation with full frequency dependent current-current interactions. Our results show that there can be a continuous transition from the Halperin-Lee-Read state to a chiral odd angular momentum Cooper pair state for short-range contact interaction. This is at odds with the previously established conclusion of first order pairing transition, in which the low frequency effective interaction was assumed for the entire frequency range. We find that even if the low frequency effective interaction is repulsive, it is compensated by the high frequency regime, which is attractive. We construct the phase diagrams and show that l = 1 angular momentum channel is quite different from higher angular momentum channel l >= 3 . Remarkably, the full frequency dependent analysis applied to the bilayer Hall system with a total filling fraction ν =1/2 +1/2 is quantitatively changed from the previously established results but not qualitatively. This work was supported by US NSF under the Grant DMR-1004520, the funds from the David S. Saxon Presidential Chair at UCLA(37952), and by the Institute for Basic Science in Korea through the Young Scientist grant (5199-2014003).
Callback response of dugongs to conspecific chirp playbacks.
Ichikawa, Kotaro; Akamatsu, Tomonari; Shinke, Tomio; Adulyanukosol, Kanjana; Arai, Nobuaki
2011-06-01
Dugongs (Dugong dugon) produce bird-like calls such as chirps and trills. The vocal responses of dugongs to playbacks of several acoustic stimuli were investigated. Animals were exposed to four different playback stimuli: a recorded chirp from a wild dugong, a synthesized down-sweep sound, a synthesized constant-frequency sound, and silence. Wild dugongs vocalized more frequently after playback of broadcast chirps than that after constant-frequency sounds or silence. The down-sweep sound also elicited more vocal responses than did silence. No significant difference was found between the broadcast chirps and the down-sweep sound. The ratio of wild dugong chirps to all calls and the dominant frequencies of the wild dugong calls were significantly higher during playbacks of broadcast chirps, down-sweep sounds, and constant-frequency sounds than during those of silence. The source level and duration of dugong chirps increased significantly as signaling distance increased. No significant correlation was found between signaling distance and the source level of trills. These results show that dugongs vocalize to playbacks of frequency-modulated signals and suggest that the source level of dugong chirps may be manipulated to compensate for transmission loss between the source and receiver. This study provides the first behavioral observations revealing the function of dugong chirps. © 2011 Acoustical Society of America
Development and initial validation of a caffeine craving questionnaire.
West, Oliver; Roderique-Davies, Gareth
2008-01-01
Craving for caffeine has received little empirical attention, despite considerable research into the potential for caffeine dependence. The main aim of this study was to develop, and initially validate, a multi-item, multidimensional instrument to measure cravings for caffeine. Participants were 189 caffeine consumers who completed the Questionnaire of Caffeine Cravings, which was based on the Questionnaire of Smoking Urges (QSU), in one of five naturally occurring periods of abstinence; 1-15 min; 16-120 mins; 3-7 h; 12-48 h and +48 h. Exploratory factor analysis suggested a three-factor solution best described the data; Factor 1 reflected strong desires, intentions and positive reinforcement; Factor 2 reflected mild/general positive and negative reinforcement and Factor 3 reflected functional/mood-based negative reinforcement. Significantly higher Factor 1 and Factor 2 scores were recorded for high frequency users; significantly higher Factor 1 and Factor 3 scores were recorded as a function of increased levels of dependence. Duration of abstinence did not significantly effect cravings across all three factors. Regression analyses suggested level of dependence best predicted both current cravings and frequency of daily use. These findings suggest caffeine cravings may be conceptualized multidimensionally and further validates the use of multidimensional, multi-item instruments. Cravings for caffeine may manifest and be detected across varying levels of dependence and, frequency of use and independently of duration of abstinence.
Lu, Xi; Hui-Chan, Christina Wan-Ying; Tsang, William Wai-Nam
2016-11-01
[Purpose] Exercise has been shown to improve cardiovascular fitness and cognitive function. Whether the inclusion of mind over exercise would increase parasympathetic control of the heart and brain activities more than general exercise at a similar intensity is not known. The aim of this study was to compare the effects of Tai Chi (mind-body exercise) versus arm ergometer cycling (body-focused exercise) on the heart rate variability and prefrontal oxygenation level. [Subjects and Methods] A Tai Chi master was invited to perform Tai Chi and arm ergometer cycling with similar exercise intensity on two separate days. Heart rate variability and prefrontal oxyhemoglobin levels were measured continuously by a RR recorder and near-infrared spectroscopy, respectively. [Results] During Tai Chi exercise, spectral analysis of heart rate variability demonstrated a higher high-frequency power as well as a lower low-frequency/high-frequency ratio than during ergometer cycling, suggesting increased parasympathetic and decreased sympathetic control of the heart. Also, prefrontal oxyhemoglobin and total hemoglobin levels were higher than those during arm ergometer exercise. [Conclusion] These findings suggest that increased parasympathetic control of the heart and prefrontal activities may be associated with Tai Chi practice. Having a "mind" component in Tai Chi could be more beneficial for older adults' cardiac health and cognitive function than body-focused ergometer cycling.
Ambient noise and temporal patterns of boat activity in the US Virgin Islands National Park.
Kaplan, Maxwell B; Mooney, T Aran
2015-09-15
Human activity is contributing increasing noise to marine ecosystems. Recent studies have examined the effects of boat noise on marine fishes, but there is limited understanding of the prevalence of this type of sound source. This investigation tracks vessel noise on three reefs in the US Virgin Islands National Park over four months in 2013. Ambient noise levels ranged from 106 to 129dBrms re 1μPa (100Hz-20kHz). Boat noise occurred in 6-12% of samples. In the presence of boat noise, ambient noise in a low-frequency band (100-1000Hz) increased by >7dB above baseline levels and sound levels were significantly higher. The frequency with the most acoustic energy shifted to a significantly lower frequency when boat noise was present during the day. These results indicate the abundance of boat noise and its overlap with reef organism sound production, raising concern for the communication abilities of these animals. Copyright © 2015 Elsevier Ltd. All rights reserved.
Digital avionics susceptibility to high energy radio frequency fields
NASA Astrophysics Data System (ADS)
Larsen, William E.
Generally, noncritical avionic systems for transport category aircraft have been designed to meet radio frequency (RF) susceptibility requirements set forth in RTCA DO 160B, environmental conditions and test procedures for airborne equipment. Section 20 of this document controls the electromagnetic interference (EMI) hardening for avionics equipment to levels of 1 and 2 V/m. Currently, US equipment manufacturers are designing flight-critical fly-by-wire avionics to a much higher level. The US Federal Aviation Administration (FAA) has requested that the RTCA SC-135 high-energy radio frequency (HERF) working group develop appropriate testing procedures for section 20 of RTCA DO 160B for radiated and conducted susceptibility at the box and systems level. The FAA has also requested the SAE AE4R committee to address installed systems testing, airframe shielding effects and RF environment monitoring. Emitters of interest include radar (ground, ship, and aircraft) commercial broadcast and TV station, mobile communication, and other transmitters that could possibly affect commercial aircraft.
Polymorphism in exon 6 of the human NT5E gene is associated with aortic valve calcification.
Kochan, Zdzislaw; Karbowska, Joanna; Gogga, Patrycja; Kutryb-Zajac, Barbara; Slominska, Ewa M; Smolenski, Ryszard T
2016-12-01
NT5E encodes ecto-5'-nucleotidase (e5NT, CD73) which hydrolyses extracellular AMP to adenosine. Adenosine has been shown to play a protective role against aortic valve calcification (AVC). We identified two nonsynonymous missense single nucleotide polymorphisms (c.1126A > G, p.T376A and c.1136T > C, p.M379T) in exon 6 of the human NT5E gene. Since both substitutions might affect e5NT activity and consequently alter extracellular adenosine levels, we evaluated the association between NT5E alleles and calcific aortic valve disease in 119 patients (95 patients with AVC and 24 controls). In AVC patients, the frequency of the G allele at c.1126 and the frequency of the GG genotype as well as the frequency of the C allele at c.1136, and the frequencies of CC and TC genotypes tended to be higher as compared to controls. The allele and genotype frequencies in AVC patients and controls were also compared to those calculated from the 1000 Genomes Project data for control individuals of European ancestry (n = 503). We found that the frequency of the C allele at c.1136 is significantly higher in patients with AVC than in the European controls (0.111 vs. 0.054, P = 0.0052). Moreover, e5NT activity in aortic valves showed a trend toward lower levels in AVC patients with CC and TC genotypes than in those with the TT genotype. Our findings indicate that the genetic polymorphism of NT5E may contribute to the pathogenesis of calcific aortic valve disease and that the C allele of SNP c.1136 is associated with an increased risk of AVC.
Zhang, Xiao; Xiao, Xinhua; Duan, Huawei; Gao, Feng; Li, Yuanyuan; Niu, Yong; Gao, Weimin; Wang, Haisheng; Yu, Shanfa; Zheng, Yuxin
2016-01-01
Diesel engine exhaust (DEE), a ubiquitous environmental pollutant, has been associated with adverse health effects. Revelation of cellular and molecular changes is critical for understanding environmental exposure-related diseases. Although the molecular-level effects of DEE exposure have been investigated, whether it is associated with aberrant changes at cellular level is largely unknown at the population level. In the present study, we measured urinary concentrations of 6 mono-hydroxylated PAHs (OH-PAHs) and cytotoxicity-related endpoints including apoptosis and necrosis frequencies, and nuclear division cytotoxicity index (NDCI) in peripheral blood lymphocytes (PBLs) of 79 DEE-exposed workers and 59 non-DEE-exposed workers. We found that DEE-exposed workers had significantly higher necrosis frequency and lower NDCI than did non-DEE-exposed workers (both p < 0.001). In all study subjects and nonsmoking workers, urinary summed OH-PAHs was associated with increased necrosis frequency and reduced NDCI. In nonsmoking workers, an interquartile range increase in urinary summed OH-PAHs was associated with 105.03% increase in necrosis frequency and 8.70% decrease in NDCI. Taking advantage of the previous measure of micronucleus frequency, we observed that micronucleus frequency was positively correlated with apoptosis and necrosis frequencies (r = 0.277, p = 0.047 and r = 0.452, p = 0.001, respectively) and negatively correlated with NDCI (r = -0.477, p < 0.001). In conclusion, our results suggested that DEE exposure was associated with increased necrosis frequency and further with reduced NDCI in PBLs, providing evidence of DEE exposure-induced cytotoxicity in humans.
Accuracy of physician-estimated probability of brain injury in children with minor head trauma.
Daymont, Carrie; Klassen, Terry P; Osmond, Martin H
2015-07-01
To evaluate the accuracy of physician estimates of the probability of intracranial injury in children with minor head trauma. This is a subanalysis of a large prospective multicentre cohort study performed from July 2001 to November 2005. During data collection for the derivation of a clinical prediction rule for children with minor head trauma, physicians indicated their estimate of the probability of brain injury visible on computed tomography (P-Injury) and the probability of injury requiring intervention (P-Intervention) by choosing one of the following options: 0%, 1%, 2%, 3%, 4%, 5%, 10%, 20%, 30%, 40%, 50%, 75%, 90%, and 100%. We compared observed frequencies to expected frequencies of injury using Pearson's χ2-test in analyses stratified by the level of each type of predicted probability and by year of age. In 3771 eligible subjects, the mean predicted risk was 4.6% (P-Injury) and 1.4% (P-Intervention). The observed frequency of injury was 4.1% (any injury) and 0.6% (intervention). For all levels of P-Injury from 1% to 40%, the observed frequency of injury was consistent with the expected frequency. The observed frequencies for the 50%, 75%, and 90% levels were lower than expected (p<0.05). For estimates of P-Intervention, the observed frequency was consistently higher than the expected frequency. Physicians underestimated risk for infants (mean P-Intervention 6.2%, actual risk 12.3%, p<0.001). Physician estimates of probability of any brain injury in children were collectively accurate for children with low and moderate degrees of predicted risk. Risk was underestimated in infants.
Sattler, Krystal M; Deane, Frank P; Tapsell, Linda; Kelly, Peter J
2018-01-01
Weight stigma is related to lower levels of motivation to exercise in overweight and obesity. This study explored the nature of the relationship between stigma, motivation to exercise and physical activity while accounting for gender differences. Participants were 439 adults with overweight and obesity (mean body mass index = 32.18 kg/m2, standard deviation = 4.09 kg/m2). Females reported significantly more frequent stigma experiences than males. Mediation models found a conditional direct effect of weight stigma for males, with higher frequency of stigma experiences related to higher levels of walking and vigorous physical activity. A conditional indirect effect was found for females for walking, moderate and vigorous levels of physical activity, with higher weight stigma related to lower autonomous motivation, and lower levels of physical activity. Findings suggest that males and females are affected differently by weight-stigma experiences. PMID:29552349
Serum 25-hydroxyvitamin D3 is related to fish intake and exercise in Korean adult men.
Lym, Youl Lee; Joh, Hee-Kyung
2009-01-01
Vitamin D is an important factor for bone health. It is uncertain which lifestyle is associated with vitamin D status, especially in healthy middle aged Asian men. A cross-sectional analysis was performed in 149 men aged 40-69 years who visited a health check-up center in Korea. Serum vitamin D (25-OHD3) was measured and smoking, alcohol, exercise, occupation, frequency of fish and dairy intake were estimated by self-administered questionnaire. The mean (+/-SD) 25-OHD3 concentration was 96.5+/-30.7 nmol/L. Higher and lower 25-OHD3 groups were generated with the median concentration as the cut-off point. By univariate analysis, exercise status and fish intake frequency were significantly different between two 25-OHD3 groups (p=0.012, 0.019 respectively). After multivariable logistic regression, higher fish intake frequency and regular exercise were associated with higher levels of 25-OHD3 (p for trend=0.017 and 0.02 respectively). In conclusion, frequent fish intake and regular exercise are positively associated with serum 25-OHD3 concentrations in healthy Korean men.
Contractor, Tanupriya; Kobayashi, Shinta; da Silva, Edaise; Clausen, Richard; Chan, Chang; Vosburgh, Evan; Tang, Laura H; Levine, Arnold J; Harris, Chris R
2016-05-24
In a mouse model for neuroendocrine tumors of the pancreas (PanNETs), liver metastasis occurred at a higher frequency in males. Male mice also had higher serum and intratumoral levels of the innate immunity protein complement C5. In mice that lost the ability to express complement C5, there was a lower frequency of metastasis, and males no longer had a higher frequency of metastasis than females. Treatment with PMX53, a small molecule antagonist of C5aR1/CD88, the receptor for complement C5a, also reduced metastasis. Mice lacking a functional gene for complement C5 had smaller primary tumors, which were less invasive and lacked the CD68+ macrophages that have previously been associated with metastasis in this type of tumor. This is the first report of a gene that causes sexual dimorphism of metastasis in a mouse model. In the human disease, which also shows sexual dimorphism for metastasis, clinically advanced tumors expressed more complement C5 than less advanced tumors.
Mooney, T Aran; Samson, Julia E; Schlunk, Andrea D; Zacarias, Samantha
2016-07-01
Sound is an abundant cue in the marine environment, yet we know little regarding the frequency range and levels which induce behavioral responses in ecologically key marine invertebrates. Here we address the range of sounds that elicit unconditioned behavioral responses in squid Doryteuthis pealeii, the types of responses generated, and how responses change over multiple sound exposures. A variety of response types were evoked, from inking and jetting to body pattern changes and fin movements. Squid responded to sounds from 80 to 1000 Hz, with response rates diminishing at the higher and lower ends of this frequency range. Animals responded to the lowest sound levels in the 200-400 Hz range. Inking, an escape response, was confined to the lower frequencies and highest sound levels; jetting was more widespread. Response latencies were variable but typically occurred after 0.36 s (mean) for jetting and 0.14 s for body pattern changes; pattern changes occurred significantly faster. These results demonstrate that squid can exhibit a range of behavioral responses to sound include fleeing, deimatic and protean behaviors, all of which are associated with predator evasion. Response types were frequency and sound level dependent, reflecting a relative loudness concept to sound perception in squid.
Blackwood, Julie C; Hastings, Alan; Mumby, Peter J
2011-10-01
The interaction between multiple stressors on Caribbean coral reefs, namely, fishing effort and hurricane impacts, is a key element in the future sustainability of reefs. We develop an analytic model of coral-algal interactions and explicitly consider grazing by herbivorous reef fish. Further, we consider changes in structural complexity, or rugosity, in addition to the direct impacts of hurricanes, which are implemented as stochastic jump processes. The model simulations consider various levels of fishing effort corresponding to' several hurricane frequencies and impact levels dependent on geographic location. We focus on relatively short time scales so we do not explicitly include changes in ocean temperature, chemistry, or sea level rise. The general features of our approach would, however, apply to these other stressors and to the management of other systems in the face of multiple stressors. It is determined that the appropriate management policy, either local reef restoration or fisheries management, greatly depends on hurricane frequency and impact level. For sufficiently low hurricane impact and macroalgal growth rate, our results indicate that regions with lower-frequency hurricanes require stricter fishing regulations, whereas management in regions with higher-frequency hurricanes might be less concerned with enhancing grazing and instead consider whether local-scale restorative activities to increase vertical structure are cost-effective.
Quantitative analysis of a frequency-domain nonlinearity indicator.
Reichman, Brent O; Gee, Kent L; Neilsen, Tracianne B; Miller, Kyle G
2016-05-01
In this paper, quantitative understanding of a frequency-domain nonlinearity indicator is developed. The indicator is derived from an ensemble-averaged, frequency-domain version of the generalized Burgers equation, which can be rearranged in order to directly compare the effects of nonlinearity, absorption, and geometric spreading on the pressure spectrum level with frequency and distance. The nonlinear effect is calculated using pressure-squared-pressure quadspectrum. Further theoretical development has given an expression for the role of the normalized quadspectrum, referred to as Q/S by Morfey and Howell [AIAA J. 19, 986-992 (1981)], in the spatial rate of change of the pressure spectrum level. To explore this finding, an investigation of the change in level for initial sinusoids propagating as plane waves through inviscid and thermoviscous media has been conducted. The decibel change with distance, calculated through Q/S, captures the growth and decay of the harmonics and indicates that the most significant changes in level occur prior to sawtooth formation. At large distances, the inviscid case results in a spatial rate of change that is uniform across all harmonics. For thermoviscous media, large positive nonlinear gains are observed but offset by absorption, which leads to a greater overall negative spatial rate of change for higher harmonics.
Corona-Strauss, Farah I.; Schick, Bernhard; Delb, Wolfgang; Strauss, Daniel J.
2012-01-01
It has been shown recently that chirp-evoked auditory brainstem responses (ABRs) show better performance than click stimulations, especially at low intensity levels. In this paper we present the development, test, and evaluation of a series of notched-noise embedded frequency specific chirps. ABRs were collected in healthy young control subjects using the developed stimuli. Results of the analysis of the corresponding ABRs using a time-scale phase synchronization stability (PSS) measure are also reported. The resultant wave V amplitude and latency measures showed a similar behavior as for values reported in literature. The PSS of frequency specific chirp-evoked ABRs reflected the presence of the wave V for all stimulation intensities. The scales that resulted in higher PSS are in line with previous findings, where ABRs evoked by broadband chirps were analyzed, and which stated that low frequency channels are better for the recognition and analysis of chirp-evoked ABRs. We conclude that the development and test of the series of notched-noise embedded frequency specific chirps allowed the assessment of frequency specific ABRs, showing an identifiable wave V for different intensity levels. Future work may include the development of a faster automatic recognition scheme for these frequency specific ABRs. PMID:26557336
Mid- to high-frequency noise from high-speed boats and its potential impacts on humpback dolphins.
Li, Songhai; Wu, Haiping; Xu, Youhou; Peng, Chongwei; Fang, Liang; Lin, Mingli; Xing, Luru; Zhang, Peijun
2015-08-01
The impact of noise made by vessels on marine animals has come under increased concern. However, most measurements on noise from vessels have only taken into account the low-frequency components. For cetaceans operating in the mid- and high-frequencies, such as the Indo-Pacific humpback dolphin (Sousa chinensis), mid- to high-frequency noise components may be of more concern, in terms of their potential impacts. In this study, noise made by a small high-speed boat was recorded using a broadband recording system in a dolphin watching area focusing on the effects on humpback dolphins in Sanniang Bay, China. The high-speed boat produced substantial mid- to high-frequency noise components with frequencies to >100 kHz, measured at three speeds: ∼40, 30, and 15 km/h. The noise from the boat raised the ambient noise levels from ∼5 to 47 decibels (dB) root-mean-square (rms) across frequency bands ranging from 1 to 125 kHz at a distance of 20 to 85 m, with louder levels recorded at higher speeds and at closer distances. To conclude, the noise produced by the small high-speed boat could be heard by Sousa chinensis and therefore potentially had adverse effects on the dolphins.
Chromosome Aberrations in Normal and Ataxia-Telangiectasia Cells Exposed to Heavy Ions
NASA Technical Reports Server (NTRS)
Kawata, T.; Ito, H.; Liu, C.; Shigematsu, N.; George, K.; Cucinotta, F. A.
2007-01-01
Although cells derived from Ataxia Telangiectasia (AT) patients are known to exhibit abnormal responses to ionizing radiations, its underlying mechanism still remains unclear. Previously, the authors reported that at the same gamma-irradiation dose AT cells show higher frequencies of misrepair and deletions compared to normal human fibroblast cells. In this study, we investigated the effects of heavy ions beams on chromosomal aberrations in normal and AT cells. Normal and AT fibroblast cells arrested at G0/G1 phase were irradiated with 2 Gy of X-rays, 490 MeV/u Silicon (LET 55 keV/m), 500 MeV/u Iron (LET 185 keV/m) and 200 MeV/u Iron (LET 440 keV/m) particles, and then cells were allowed to repair for 24 hours at 37 degrees before subculture. Calyculin-A induced PCC method was employed to collect G2/M chromosomes and whole DNA probes 1 and 3 were used to analyze chromosomal aberrations such as color-junctions, deletions, simple exchanges (incomplete and reciprocal exanges) and complex-type exchanges. The percentages of aberrant cells were higher when normal and AT cells were exposed to heavy ions compared to X-rays, and had a tendency to increase with increasing LET up to 185 keV/m and then decreased at 440 keV/m. When the frequency of color-junctions per cell was compared after X-ray exposure, AT cells had around three times higher frequency of color-junctions (mis-rejoining) than normal cells. However, at 185 keV/m there was no difference in the frequency of color-junctions between two cell lines. It was also found that the frequency of simple exchanges per cell was almost constant in AT cells regardless LET levels, but it was LET dependent for normal cells. Interestingly, the frequency of simple exchanges was higher for AT cells when it was compared at 185 keV/m but AT cells had more complex-type exchanges at the same LET levels. Heavy ions are more efficient in inducing chromosome aberrations in normal and AT cells compared to X-rays, and the aberration types between normal and AT fibroblast appeared different probably due to difference in the ATM gene function.
Latash, M L
1992-07-01
In the framework of the equilibrium-point hypothesis, virtual trajectories and patterns of joint stiffness were reconstructed during voluntary single-joint oscillatory movements in the elbow joint at a variety of frequencies and against two inertial loads. At low frequencies, virtual trajectories were in-phase with the actual joint trajectories. Joint stiffness changed at a doubled frequency. An increase in movement frequency and/or inertial load led to an increase in the difference between the peaks of the actual and virtual trajectories and in both peak and averaged values of joint stiffness. At a certain, critical frequency, virtual trajectory was nearly flat. Further increase in movement frequency led to a 180 degree phase shift between the actual and virtual trajectories. The assessed values of the natural frequency of the system "limb + manipulandum" were close to the critical frequencies for both low and high inertial loads. Peak levels and integrals of the electromyograms of two flexor and two extensor muscles changed monotonically with movement frequency without any special behavior at the critical frequencies. Nearly flat virtual trajectories at the natural frequency make physical sense as hypothetical control signals, unlike the electromyographic recordings, since a system at its natural frequency requires minimal central interference. Modulation of joint stiffness is assumed to be an important adaptive mechanism attenuating difference between the system's natural frequency and desired movement frequency. Virtual trajectory is considered a behavioral observable. Phase transitions between the virtual and actual trajectories are illustrations of behavioral discontinuities introduced by slow changes in a higher level control parameter, movement frequency. Relative phase shift between these two trajectories may be considered an order parameter.
Okubo, Hitomi; Miyake, Yoshihiro; Sasaki, Satoshi; Tanaka, Keiko; Hirota, Yoshio
2016-06-01
Evidence from Western countries shows that higher consumption of sugar-sweetened beverages (SSBs) is associated with lower quality of young children's diets, but little is known about these relations in non-Western countries with relatively low consumption levels of SSBs. We hypothesized that SSB consumption in infancy would be associated with poor quality of later food and nutrient intake patterns among Japanese young children. The study subjects were 493 Japanese mother-child pairs from a prospective birth cohort study. Dietary data on children were collected from the mothers using self-administered questionnaires when the children were aged 16-24 months and 41-49 months. Multiple linear regression analyses were used to examine the relationships between SSB consumption frequency in infancy and later intake of foods and nutrients. At 16-24 months of age, more than half of the children (56.4%) consumed SSBs less than once a week, whereas 11.6% consumed SSBs at least once daily. More frequent consumption of SSBs in infancy was associated with higher intake of confectionaries and SSBs and lower intake of fruits and vegetables at 41-49 months of age. These associations were still evident after adjustment for maternal SSB consumption and socioeconomic status. At the nutrient level, SSB consumption frequency was positively associated with energy intake and inversely associated with intake of many nutrients, such as protein, dietary fiber, and most of the micronutrients examined. In conclusion, higher consumption frequency of SSBs at an early age is associated with poor quality of overall dietary intake among young Japanese children 1.5-2.5 years later. Copyright © 2016 Elsevier Inc. All rights reserved.
Vowel selection and its effects on perturbation and nonlinear dynamic measures.
Maccallum, Julia K; Zhang, Yu; Jiang, Jack J
2011-01-01
Acoustic analysis of voice is typically conducted on recordings of sustained vowel phonation. This study applied perturbation and nonlinear dynamic analyses to the vowels /a/, /i/, and /u/ in order to determine vowel selection effects on analysis. Forty subjects (20 males and 20 females) with normal voices participated in recording. Traditional parameters of fundamental frequency, signal-to-noise ratio, percent jitter, and percent shimmer were calculated for the signals using CSpeech. Nonlinear dynamic parameters of correlation dimension and second-order entropy were also calculated. Perturbation analysis results were largely incongruous in this study and in previous research. Fundamental frequency results corroborated previous work, indicating higher fundamental frequency for /i/ and /u/ and lower fundamental frequency for /a/. Signal-to-noise ratio results showed that /i/ and /u/ have greater harmonic levels than /a/. Results of nonlinear dynamic analysis suggested that more complex activity may be evident in /a/ than in /i/ or /u/. Percent jitter and percent shimmer may not be useful for description of acoustic differences between vowels. Fundamental frequency, signal-to-noise ratio, and nonlinear dynamic parameters may be applied to characterize /a/ as having lower frequency, higher noise, and greater nonlinear components than /i/ and /u/. Copyright © 2010 S. Karger AG, Basel.
Xie, Zheng; Lin, Haijiang; Fang, Renfei; Shen, Weiwei; Li, Shuguang; Chen, Bo
2015-05-06
Coke oven workers (COWs) are exposed to high level of genotoxic chemicals that induce oxidative stress and genetic damage. The dietary intake of certain types of foods may reverse these effects. We conducted a cross-sectional study with 51 topside COWs, 79 other COWs, and 67 controls, to assess the effects of dietary patterns on oxidative stress and genetic damage. Compared to the controls, both topside and other COWs had significantly higher urinary 1-hydroxypyrene levels, serum oxidant levels [malondialdehyde, (MDA)], and genetic damage [micronucleus (MN) frequency & 8-oxo-2'-deoxyguanosine (8-OH-dG)], but lower antioxidant levels [superoxide dismutase (SOD) and glutathione peroxidase, (GPx)]. The fruit-vegetable (FV) dietary pattern was positively correlated with serum SOD levels and negative correlated with serum MDA, MN frequency, and urinary 8-OH-dG. COWs with an FV patter in the highest quartile (Q4) had significantly increased antioxidant levels (SOD and GPx) and decreased oxidant levels (MDA) and genetic damage (MN frequency and 8-OH-dG) than those with an FV pattern in the lowest quartile (Q1). Compared to control subjects, COWs had increased oxidative stress and genetic damage. A FV dietary pattern may reverse oxidative stress and genetic damage in COWs.
Acoustic challenges of the A400M for active systems
NASA Astrophysics Data System (ADS)
Breitbach, Harald; Sachau, Delf; Böhme, Sten
2006-03-01
In some types of aircraft tonal interior noise with high sound pressure level (up to 110 dB(A)) occurs at low frequencies (f < 500 Hz). Typical examples are propeller driven aircraft, for which the excitation frequencies are given by the blade passage frequency (BPF) and its higher harmonics. The high tonal noise levels at these frequencies can occur due to the fact that the blades' profiles are only optimized in terms of aerodynamics. The acoustic properties are usually not taken into account. In order to obtain an acceptable interior noise level, and to guarantee both work-safety and comfort in the aircraft interiors, passive methods are commonly used - e.g. adding material with high damping or vibration absorbing qualities. Especially when low frequency noise has to be reduced, adding material results in a lot of unwanted additional weight. In order to avoid this extra weight, the concept of active noise reduction (ANR) and tunable vibration absorber systems (TVA), which focus on the unwanted tonal noise, are a good compromise of treating noise and the amount of additional weight in aircraft design. This paper briefly discusses two different possible methods to reduce the low frequency noise. The noise reduction of tuned vibration absorbers (TVA) mounted on the airframe are nowadays commonly used in propeller driven aircraft and can be predicted by vibroacoustic finite element calculations, which is described in this paper. In order to abide to industrial safety regulations, the noise level inside the semi closed loadmaster area (LMA) must be reduced down to a noise level, which is even 8 dB(A) below the specified cargo hold noise level. The paper describes also the phases of development of an ANR system that could be used to control the sound pressure level inside the LMA. The concept is verified by experimental investigations within a mock up of the LMA.
Spectral analysis to assess exposure to extremely low frequency magnetic fields in cars.
Paniagua, Jesús M; Rufo, Montaña; Jiménez, Antonio; Antolín, Alicia; Barberá, Jorge
2017-04-15
A type of contamination that has been little studied in cars comes from the extremely low frequency (ELF) magnetic fields generated by the vehicle's electrical devices and the magnetized metal in the tyres. The magnetic fields in cars are frequently analysed with broadband meters sensitive to a frequency range above 30Hz. This has the disadvantage that they neither detect the magnetic field of the spinning tyres nor give any information on the spectral components, which makes it impossible to adequately assess exposure. The objective of the present study was to perform spectral analyses of ELF magnetic fields in cars, to identify their frequencies, and to assess exposure based on the ICNIRP regulatory guidelines. To do this, a meter and a spectrum analyser sensitive to magnetic fields in the 5Hz-2kHz frequency range were used. Spectra were acquired for different seats, heights, and speeds, and spatially averaged exposure coefficients were calculated. The results indicated that the main emissions were detected in the 5-100Hz range, where the wheel rotation frequencies and their harmonics are found. The intensity of the rest of the emissions were negligible in comparison. The exposure quotient increases with speed, and is approximately twice as great at foot level as at head level. The magnetic field levels are lower than the reference levels (the maximum represents 3% of the ICNIRP standard), but higher than those found in residential environments and than the cut-off threshold used by the IARC to classify ELF magnetic fields in Group 2B. Copyright © 2017 Elsevier B.V. All rights reserved.
Changing flood frequencies under opposing late Pleistocene eastern Mediterranean climates.
Ben Dor, Yoav; Armon, Moshe; Ahlborn, Marieke; Morin, Efrat; Erel, Yigal; Brauer, Achim; Schwab, Markus Julius; Tjallingii, Rik; Enzel, Yehouda
2018-05-31
Floods comprise a dominant hydroclimatic phenomenon in aridlands with significant implications for humans, infrastructure, and landscape evolution worldwide. The study of short-term hydroclimatic variability, such as floods, and its forecasting for episodes of changing climate therefore poses a dominant challenge for the scientific community, and predominantly relies on modeling. Testing the capabilities of climate models to properly describe past and forecast future short-term hydroclimatic phenomena such as floods requires verification against suitable geological archives. However, determining flood frequency during changing climate is rarely achieved, because modern and paleoflood records, especially in arid regions, are often too short or discontinuous. Thus, coeval independent climate reconstructions and paleoflood records are required to further understand the impact of climate change on flood generation. Dead Sea lake levels reflect the mean centennial-millennial hydrological budget in the eastern Mediterranean. In contrast, floods in the large watersheds draining directly into the Dead Sea, are linked to short-term synoptic circulation patterns reflecting hydroclimatic variability. These two very different records are combined in this study to resolve flood frequency during opposing mean climates. Two 700-year-long, seasonally-resolved flood time series constructed from late Pleistocene Dead Sea varved sediments, coeval with significant Dead Sea lake level variations are reported. These series demonstrate that episodes of rising lake levels are characterized by higher frequency of floods, shorter intervals between years of multiple floods, and asignificantly larger number of years that experienced multiple floods. In addition, floods cluster into intervals of intense flooding, characterized by 75% and 20% increased frequency above their respective background frequencies during rising and falling lake-levels, respectively. Mean centennial precipitation in the eastern Mediterranean is therefore coupled with drastic changes in flood frequencies. These drastic changes in flood frequencies are linked to changes in the track, depth, and frequency of mid-latitude eastern Mediterranean cyclones, determining mean climatology resulting in wetter and drier regional climatic episodes.
NASA Astrophysics Data System (ADS)
Kawata, Tetsuya; George, Ms Kerry; Cucinotta, Francis A.; Shigematsu, Naoyuki; Ito, Hisao; Furusawa, Yoshiya; Uno, Takashi
We investigated the effects of heavy ions beams on chromosomal aberrations in normal and AT cells. Normal and AT fibroblast cells arrested at G0/G1 phase were irradiated with 2 Gy of X-rays, 490 MeV/u Silicon (LET 55 keV/micron), 500 MeV/u Iron (LET 185 keV/micron) and 200 MeV/u Iron (LET 440 keV/micron) particles, and then cells were allowed to repair for 24 hours at 37 degrees before subculture. Calyculin-A induced PCC method was employed to collect G2/M chromosomes and whole DNA probes 1 and 3 were used to analyze chromosomal aberrations such as color-junctions, deletions, simple exchanges (incomplete and reciprocal exchanges) and complex-type exchanges. The percentages of aberrant cells were higher when normal and AT cells were exposed to heavy ions compared to X-rays, and had a tendency to increase with increasing LET up to 185 keV/micron and then decreased at 440 keV/micron. When the frequency of color-junctions per cell was compared after X-ray exposure, AT cells had around three times higher frequency of color-junctions (mis-rejoining) than normal cells. However, at 185 keV/micron there was no difference in the frequency of color-junctions between two cell lines. It was also found that the frequency of simple exchanges per cell was almost constant in AT cells regardless LET levels, but it was LET dependent for normal cells. Interestingly, the frequency of simple exchanges was higher for normal fibroblast cells when it was compared at 185 keV/micron, but AT cells had more complex-type exchanges at the same LET levels. Heavy ions are more efficient in inducing chromosome aberrations in normal and AT cells compared to X-rays, and the aberration types between normal and AT fibroblast appeared different probably due to difference in the ATM gene function.
NASA Astrophysics Data System (ADS)
Wei, Kai; Wang, Feng; Wang, Ping; Liu, Zi-xuan; Zhang, Pan
2017-03-01
The soft under baseplate pad of WJ-8 rail fastener frequently used in China's high-speed railways was taken as the study subject, and a laboratory test was performed to measure its temperature and frequency-dependent dynamic performance at 0.3 Hz and at -60°C to 20°C with intervals of 2.5°C. Its higher frequency-dependent results at different temperatures were then further predicted based on the time-temperature superposition (TTS) and Williams-Landel-Ferry (WLF) formula. The fractional derivative Kelvin-Voigt (FDKV) model was used to represent the temperature- and frequency-dependent dynamic properties of the tested rail pad. By means of the FDKV model for rail pads and vehicle-track coupled dynamic theory, high-speed vehicle-track coupled vibrations due to temperature- and frequency-dependent dynamic properties of rail pads was investigated. Finally, further combining with the measured frequency-dependent dynamic performance of vehicle's rubber primary suspension, the high-speed vehicle-track coupled vibration responses were discussed. It is found that the storage stiffness and loss factor of the tested rail pad are sensitive to low temperatures or high frequencies. The proposed FDKV model for the frequency-dependent storage stiffness and loss factors of the tested rail pad can basically meet the fitting precision, especially at ordinary temperatures. The numerical simulation results indicate that the vertical vibration levels of high-speed vehicle-track coupled systems calculated with the FDKV model for rail pads in time domain are higher than those calculated with the ordinary Kelvin-Voigt (KV) model for rail pads. Additionally, the temperature- and frequency-dependent dynamic properties of the tested rail pads would alter the vertical vibration acceleration levels (VALs) of the car body and bogie in 1/3 octave frequencies above 31.5 Hz, especially enlarge the vertical VALs of the wheel set and rail in 1/3 octave frequencies of 31.5-100 Hz and above 315 Hz, which are the dominant frequencies of ground vibration acceleration and rolling noise (or bridge noise) caused by high-speed railways respectively. Since the fractional derivative value of the adopted rubber primary suspension, unlike the tested rail pad, is very close to 1, its frequency-dependent dynamic performance has little effect on high-speed vehicle-track coupled vibration responses.
Ocean noise in the tropical and subtropical Pacific Ocean.
Sirović, Ana; Wiggins, Sean M; Oleson, Erin M
2013-10-01
Ocean ambient noise is well studied in the North Pacific and North Atlantic but is poorly described for most of the worlds' oceans. Calibrated passive acoustic recordings were collected during 2009-2010 at seven locations in the central and western tropical and subtropical Pacific. Monthly and hourly mean power spectra (15-1000 Hz) were calculated in addition to their skewness, kurtosis, and percentile distributions. Overall, ambient noise at these seven sites was 10-20 dB lower than reported recently for most other locations in the North Pacific. At frequencies <100 Hz, spectrum levels were equivalent to those predicted for remote or light shipping. Noise levels in the 40 Hz band were compared to the presence of nearby and distant ships as reported to the World Meteorological Organization Voluntary Observing Ship Scheme (VOS) project. There was a positive, but nonsignificant correlation between distant shipping and low frequency noise (at 40 Hz). There was a seasonal variation in ambient noise at frequencies >200 Hz with higher levels recorded in the winter than in the summer. Several species of baleen whales, humpback (Megaptera novaeangliae), blue (Balaenoptera musculus), and fin (B. physalus) whales, also contributed seasonally to ambient noise in characteristic frequency bands.
Frequency dependence of the maximum operating temperature for quantum-cascade lasers up to 5.4 THz
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wienold, M.; Humboldt Universität zu Berlin, Institut für Physik, Newtonstr. 15, 12489 Berlin; Deutsches Zentrum für Luft und Raumfahrt, Rutherfordstr. 2, 12489 Berlin
2015-11-16
We report on the observation of an approximately linear reduction in the maximum operating temperature with an increasing emission frequency for terahertz quantum-cascade lasers between 4.2 and 5.4 THz. These lasers are based on the same design type, but vary in period length and barrier height for the cascade structure. The sample emitting at the highest frequency around 5.4 THz can be operated in pulsed mode up to 56 K. We identify an additional relaxation channel for electrons by longitudinal optical phonon scattering from the upper to the lower laser level and increasing optical losses toward higher frequencies as major processes,more » leading to the observed temperature behavior.« less
Interior noise reduction by alternate resonance tuning
NASA Technical Reports Server (NTRS)
Bliss, Donald B.; Gottwald, James A.; Bryce, Jeffrey W.
1987-01-01
Existing interior noise reduction techniques for aircraft fuselages perform reasonably well at higher frequencies, but are inadequate at low frequencies, particularly with respect to the low blade passage harmonics with high forcing levels found in propeller aircraft. A method is studied which considers aircraft fuselages lined with panels alternately tuned to frequencies above and below the frequency that must be attenuated. Adjacent panel would oscillate at equal amplitude, to give equal acoustic source strength, but with opposite phase. Provided these adjacent panels are acoustically compact, the resulting cancellation causes the interior acoustic modes to be cut off, and therefore be nonpropagating and evanescent. This interior noise reduction method, called Alternate Resonance Tuning (ART), is being investigated theoretically and experimentally. Progress to date is discussed.
Interleukin-18 -607C/A gene polymorphism in Egyptian asthmatic children.
Shaaban, Hala Hamdi; Mohy, Abeer Mohamed; Abdel-Razek, Abdel-Rahman Ahmed; Wahab, Amira Abdel
2014-08-01
Asthma is a multifactorial respiratory disease determined by interactions of multiple disease susceptibility genes and environmental factors. Interleukin (IL)-18 is an important cytokine for initiating and perpetuating the catabolic and inflammatory response in allergic asthma. A number of single nucleotide polymorphisms that influence IL-18 production are found in the gene promoter region. The aim of this study was to investigate the association of IL-18 -607C/A promoter polymorphism with asthma and whether this polymorphism influenced the severity of asthma in affected children. The influence of this promoter gene polymorphism on total serum IgE level in studied subjects was also investigated. This study was carried out at the Allergy Clinic of Abu El Reesh Children's Hospital at Cairo University, Egypt. This study included 40 asthmatic children, subdivided into four groups according to different degrees of asthma severity, and 20 apparently healthy subjects as the control group. All cases were subjected to history taking, clinical examination, and the following laboratory investigations: complete blood count, total serum IgE level assay by ELISA and genomic DNA extraction, and analysis for IL-18 -607C/A promoter gene polymorphism using the PCR-RFLP (restriction fragment length polymorphism) technique. In the present study the IL-18 -607AA genotype frequency was higher in cases (22.5 %) than in the control group (15 %); however, the difference was not statistically significant (p = 0.773). No statistically significant difference between the degree of asthma severity and IL-18 -607C/A polymorphism was found (p = 0.489). No significant association could be detected upon comparing the frequencies of C and A alleles among the two studied groups (p = 0.366). Also, no significant differences were demonstrated for the allele frequencies when the intermittent with mild [odds ratio (OR) = 2.72, 95 % CI 1.03-2.33, p = 0.067], intermittent with moderate, and severe (OR = 2.8, 95 % CI 1.01-8.5, p = 0.066) asthma groups were compared. The median value of the total serum IgE level in asthmatic cases with the mutant genotype (AA) was significantly higher [360 IU/L (96.6-1,340 IU/L)] than in the control group [119 IU/L (70.6-158.9 IU/L)] (p = 0.033). No significant statistical difference was encountered regarding the distribution of IL-18 -607C/A genotypes and allele frequencies in asthma patients and healthy controls. Also, there were no significant associations between asthma severity and different genotypes or alleles. The median value of the total serum IgE level in asthmatic cases with the mutant genotype (AA) was significantly higher than in the control group. Thus, IL-18 -607AA genotype frequency might be related to higher total serum IgE.
Luyen, Hung; Gao, Fuqiang; Hagness, Susan C; Behdad, Nader
2014-06-01
We demonstrate the feasibility of using high-frequency microwaves for tissue ablation by comparing the performance of a 10 GHz microwave ablation system with that of a 1.9 GHz system. Two sets of floating sleeve dipole antennas operating at these frequencies were designed and fabricated for use in ex vivo experiments with bovine livers. Combined electromagnetic and transient thermal simulations were conducted to analyze the performance of these antennas. Subsequently, a total of 16 ablation experiments (eight at 1.9 GHz and eight at 10.0 GHz) were conducted at a power level of 42 W for either 5 or 10 min. In all cases, the 1.9 and 10 GHz experiments resulted in comparable ablation zone dimensions. Temperature monitoring probes revealed faster heating rates in the immediate vicinity of the 10.0 GHz antenna compared to the 1.9 GHz antenna, along with a slightly delayed onset of heating farther from the 10 GHz antenna, suggesting that heat conduction plays a greater role at higher microwave frequencies in achieving a comparably sized ablation zone. The results obtained from these experiments agree very well with the combined electromagnetic/thermal simulation results. These simulations and experiments show that using lower frequency microwaves does not offer any significant advantages, in terms of the achievable ablation zones, over using higher frequency microwaves. Indeed, it is demonstrated that high-frequency microwave antennas may be used to create reasonably large ablation zones. Higher frequencies offer the advantage of smaller antenna size, which is expected to lead to less invasive interstitial devices and may possibly lead to the development of more compact multielement arrays with heating properties not available from single-element antennas.
Witczak, Monika; Ferenc, Tomasz; Gulczyńska, Ewa; Nowakowska, Dorota; Łopaczyńska, Dobrosława; Wilczyński, Jan
2014-03-15
Pregestational diabetes mellitus (type 1 and type 2) affects about 1% of the obstetric population. In diabetes, persistent hyperglycemia can be a source of DNA damage via overproduction of reactive oxygen species (ROS). Using the cytokinesis-block micronucleus (CBMN) test, we measured the frequencies of micronuclei (MN) per 1000 binucleated (BN) cells in pregnant women (mothers) with type 1 diabetes mellitus (T1DM) and in their newborns. Peripheral blood lymphocytes were collected from 17 pregnant women with T1DM and cord-blood lymphocytes from their 17 newborns. The control group included 40 pregnant women (mothers) without diabetes mellitus (DM) and their 40 newborns. In the group of pregnant women with T1DM, the mean number of MN per 1000 BN cells was 2.35 (±1.07), significantly (p<0.001) higher than in the control group of pregnant women (0.86±0.90). The frequency value in the group of newborns of T1DM mothers was 1.42 (±0.60), significantly (p<0.05) higher than in the corresponding control group (0.67±0.79). The value in the group of mothers with T1DM was significantly (p<0.05) higher than in their newborns. Comparing mothers without DM with their newborns, no significant frequency differences were observed. No significant correlations were observed between MN frequencies in mothers with T1DM and either the frequencies in their newborns, the duration of diabetes, or HbA1C levels. Our results indicate that T1DM is accompanied by increased frequencies of MN in pregnant women and their newborns. Copyright © 2014 Elsevier B.V. All rights reserved.
Pouplin, Samuel; Roche, Nicolas; Antoine, Jean-Yves; Vaugier, Isabelle; Pottier, Sandra; Figere, Marjorie; Bensmail, Djamel
2017-06-01
To determine whether activation of the frequency of use and automatic learning parameters of word prediction software has an impact on text input speed. Forty-five participants with cervical spinal cord injury between C4 and C8 Asia A or B accepted to participate to this study. Participants were separated in two groups: a high lesion group for participants with lesion level is at or above C5 Asia AIS A or B and a low lesion group for participants with lesion is between C6 and C8 Asia AIS A or B. A single evaluation session was carried out for each participant. Text input speed was evaluated during three copying tasks: • without word prediction software (WITHOUT condition) • with automatic learning of words and frequency of use deactivated (NOT_ACTIV condition) • with automatic learning of words and frequency of use activated (ACTIV condition) Results: Text input speed was significantly higher in the WITHOUT than the NOT_ACTIV (p< 0.001) or ACTIV conditions (p = 0.02) for participants with low lesions. Text input speed was significantly higher in the ACTIV than in the NOT_ACTIV (p = 0.002) or WITHOUT (p < 0.001) conditions for participants with high lesions. Use of word prediction software with the activation of frequency of use and automatic learning increased text input speed in participants with high-level tetraplegia. For participants with low-level tetraplegia, the use of word prediction software with frequency of use and automatic learning activated only decreased the number of errors. Implications in rehabilitation Access to technology can be difficult for persons with disabilities such as cervical spinal cord injury (SCI). Several methods have been developed to increase text input speed such as word prediction software.This study show that parameter of word prediction software (frequency of use) affected text input speed in persons with cervical SCI and differed according to the level of the lesion. • For persons with high-level lesion, our results suggest that this parameter must be activated so that text input speed is increased. • For persons with low lesion group, this parameter must be activated so that the numbers of errors are decreased. • In all cases, the activation of the parameter of frequency of use is essential in order to improve the efficiency of the word prediction software. • Health-related professionals should use these results in their clinical practice for better results and therefore better patients 'satisfaction.
Wave Field Characterization Using Dual-Polarized Pulse-Doppler X-Band Radar
2012-06-01
spectrum (frequencies higher than that associated with the wind wave peak) are similar for the buoy and Doppler, and likewise for the ultrasound array and...values of the RCS and ultrasound array relative to the buoy and Doppler are due to the formers’ larger energy levels at high frequencies. NSWCCD-50-TR...pp. 199- 203, 2008. [II] W. J. Plant, W. C. Keller, A. B. Reeves, E. A. Uliana, and J. W. Johnson, " Airborne microwave Doppler measurements of
2013-05-01
to data collection, a rough estimate of each listener’s binaural hearing threshold (with a bare head) was obtained for each of the test frequencies...spectral information that allows disambiguation of binaural cues lies primarily in the higher frequencies. For the analysis shown in the second...Moore, 2012). The binaural cues of level and phase differences are fairly robust; however, they can only help to determine locations on the left-right
Examination of the neighborhood activation theory in normal and hearing-impaired listeners.
Dirks, D D; Takayanagi, S; Moshfegh, A; Noffsinger, P D; Fausti, S A
2001-02-01
Experiments were conducted to examine the effects of lexical information on word recognition among normal hearing listeners and individuals with sensorineural hearing loss. The lexical factors of interest were incorporated in the Neighborhood Activation Model (NAM). Central to this model is the concept that words are recognized relationally in the context of other phonemically similar words. NAM suggests that words in the mental lexicon are organized into similarity neighborhoods and the listener is required to select the target word from competing lexical items. Two structural characteristics of similarity neighborhoods that influence word recognition have been identified; "neighborhood density" or the number of phonemically similar words (neighbors) for a particular target item and "neighborhood frequency" or the average frequency of occurrence of all the items within a neighborhood. A third lexical factor, "word frequency" or the frequency of occurrence of a target word in the language, is assumed to optimize the word recognition process by biasing the system toward choosing a high frequency over a low frequency word. Three experiments were performed. In the initial experiments, word recognition for consonant-vowel-consonant (CVC) monosyllables was assessed in young normal hearing listeners by systematically partitioning the items into the eight possible lexical conditions that could be created by two levels of the three lexical factors, word frequency (high and low), neighborhood density (high and low), and average neighborhood frequency (high and low). Neighborhood structure and word frequency were estimated computationally using a large, on-line lexicon-based Webster's Pocket Dictionary. From this program 400 highly familiar, monosyllables were selected and partitioned into eight orthogonal lexical groups (50 words/group). The 400 words were presented randomly to normal hearing listeners in speech-shaped noise (Experiment 1) and "in quiet" (Experiment 2) as well as to an elderly group of listeners with sensorineural hearing loss in the speech-shaped noise (Experiment 3). The results of three experiments verified predictions of NAM in both normal hearing and hearing-impaired listeners. In each experiment, words from low density neighborhoods were recognized more accurately than those from high density neighborhoods. The presence of high frequency neighbors (average neighborhood frequency) produced poorer recognition performance than comparable conditions with low frequency neighbors. Word frequency was found to have a highly significant effect on word recognition. Lexical conditions with high word frequencies produced higher performance scores than conditions with low frequency words. The results supported the basic tenets of NAM theory and identified both neighborhood structural properties and word frequency as significant lexical factors affecting word recognition when listening in noise and "in quiet." The results of the third experiment permit extension of NAM theory to individuals with sensorineural hearing loss. Future development of speech recognition tests should allow for the effects of higher level cognitive (lexical) factors on lower level phonemic processing.
Tomie, A; Aguado, A S; Pohorecky, L A; Benjamin, D
2000-03-01
Pavlovian autoshaping CRs are directed and reflexive consummatory responses targeted at objects repeatedly paired with rewarding substances. To evaluate the hypothesis that autoshaping may provide an animal learning model of vulnerability to drug abuse, this study relates individual differences in lever-press autoshaping CR performance in rats to stress-induced corticosterone release and tissue monoamine levels in the mesolimbic dopamine tract. Long-Evans rats (n = 14) were given 20 sessions of Pavlovian autoshaping training wherein the insertion of a retractable lever CS was followed by the response-independent presentation of food US. Large between-subjects differences in lever-press autoshaping CR performance were observed, with group high CR frequency (n = 5) performing many more lever press CRs than group low CR frequency (n = 9). Tail-blood samples were obtained before and after the 20th autoshaping session, then 24 h later the rats were sacrificed and dissection yielded tissue samples of nucleus accumbens (NAC), prefrontal cortex (PFC), caudate putamen (CP), and ventral tegmental area (VTA). Serum levels of postsession corticosterone were elevated in group high CR frequency. HPLC revealed that group high CR frequency had higher tissue levels of dopamine and DOPAC in NAC, lower levels of DOPAC/DA turnover in CP, and lower levels of 5-HIAA and lower 5-HIAA/5-HT turnover in VTA. The neurochemical profile of rats that perform more autoshaping CRs share some features of vulnerability to drug abuse.
Leader emergence through interpersonal neural synchronization
Jiang, Jing; Chen, Chuansheng; Dai, Bohan; Shi, Guang; Ding, Guosheng; Liu, Li; Lu, Chunming
2015-01-01
The neural mechanism of leader emergence is not well understood. This study investigated (i) whether interpersonal neural synchronization (INS) plays an important role in leader emergence, and (ii) whether INS and leader emergence are associated with the frequency or the quality of communications. Eleven three-member groups were asked to perform a leaderless group discussion (LGD) task, and their brain activities were recorded via functional near infrared spectroscopy (fNIRS)-based hyperscanning. Video recordings of the discussions were coded for leadership and communication. Results showed that the INS for the leader–follower (LF) pairs was higher than that for the follower–follower (FF) pairs in the left temporo-parietal junction (TPJ), an area important for social mentalizing. Although communication frequency was higher for the LF pairs than for the FF pairs, the frequency of leader-initiated and follower-initiated communication did not differ significantly. Moreover, INS for the LF pairs was significantly higher during leader-initiated communication than during follower-initiated communications. In addition, INS for the LF pairs during leader-initiated communication was significantly correlated with the leaders’ communication skills and competence, but not their communication frequency. Finally, leadership could be successfully predicted based on INS as well as communication frequency early during the LGD (before half a minute into the task). In sum, this study found that leader emergence was characterized by high-level neural synchronization between the leader and followers and that the quality, rather than the frequency, of communications was associated with synchronization. These results suggest that leaders emerge because they are able to say the right things at the right time. PMID:25831535
Leader emergence through interpersonal neural synchronization.
Jiang, Jing; Chen, Chuansheng; Dai, Bohan; Shi, Guang; Ding, Guosheng; Liu, Li; Lu, Chunming
2015-04-07
The neural mechanism of leader emergence is not well understood. This study investigated (i) whether interpersonal neural synchronization (INS) plays an important role in leader emergence, and (ii) whether INS and leader emergence are associated with the frequency or the quality of communications. Eleven three-member groups were asked to perform a leaderless group discussion (LGD) task, and their brain activities were recorded via functional near infrared spectroscopy (fNIRS)-based hyperscanning. Video recordings of the discussions were coded for leadership and communication. Results showed that the INS for the leader-follower (LF) pairs was higher than that for the follower-follower (FF) pairs in the left temporo-parietal junction (TPJ), an area important for social mentalizing. Although communication frequency was higher for the LF pairs than for the FF pairs, the frequency of leader-initiated and follower-initiated communication did not differ significantly. Moreover, INS for the LF pairs was significantly higher during leader-initiated communication than during follower-initiated communications. In addition, INS for the LF pairs during leader-initiated communication was significantly correlated with the leaders' communication skills and competence, but not their communication frequency. Finally, leadership could be successfully predicted based on INS as well as communication frequency early during the LGD (before half a minute into the task). In sum, this study found that leader emergence was characterized by high-level neural synchronization between the leader and followers and that the quality, rather than the frequency, of communications was associated with synchronization. These results suggest that leaders emerge because they are able to say the right things at the right time.
Descriptive analysis of combine cabin vibrations and their effect on the human body
NASA Astrophysics Data System (ADS)
Hostens, I.; Ramon, H.
2003-09-01
All on- and off-road vehicles are exposed to vibrations caused by unevenness of road or soil profile, moving elements within the machine or implements. A higher prevalence of low back pain is found in drivers of off-road machinery than in other drivers. In this study, significantly higher levels of low-frequency vibrations are found in the cabin of a combine, driving at high speed (20 km/h) on a concrete surface, compared to driving slower on field road. Comfort values indicate that injury can result from long-term driving on the field as well as on a concrete road. As seats with suspension systems are the main transmission paths of vibration towards the spine of the driver, their vibration attenuating characteristics play an important role in comfort assessment. The resonant frequency of seats with passive suspension system, used in agricultural machinery, lies in the low-frequency range most excited in agricultural machinery. A seat with air suspension is found to attenuate better frequencies above 4 Hz and provide more comfort to the driver than a seat with a mechanical suspension.
Zorn, Reiner; Yin, Huajie; Lohstroh, Wiebke; Harrison, Wayne; Budd, Peter M; Pauw, Brian R; Böhning, Martin; Schönhals, Andreas
2018-01-17
Polymers with intrinsic microporosity are promising candidates for the active separation layer in gas separation membranes. Here, the vibrational density of states (VDOS) for PIM-1, the prototypical polymer with intrinsic microporosity, is investigated by means of inelastic neutron scattering. The results are compared to data measured for a more conventional high-performance polyimide used in gas separation membranes (Matrimid). The measured data show the characteristic low frequency excess contribution to VDOS above the Debye sound wave level, generally known as the Boson peak in glass-forming materials. In comparison to the Boson peak of Matrimid, that of PIM-1 is shifted to lower frequencies. This shift is discussed considering the microporous, sponge-like structure of PIM-1 as providing a higher compressibility at the molecular scale than for conventional polymers. For an annealed PIM-1 sample, the Boson peak shifts to higher frequencies in comparison to the un-annealed sample. These changes in the VDOS of the annealed PIM-1 sample are related to changes in the microporous structure as confirmed by X-ray scattering.
Divella, Rosa; Mazzocca, Antonio; Gadaleta, Cosimo; Simone, Giovanni; Paradiso, Angelo; Quaranta, Michele; Daniele, Antonella
2012-01-01
Hepatocarcinogenesis is heavily influenced by chronic hepatitis B (HBV) and C (HCV) infection. Elevated levels of plasminogen activator inhibitor-1 (SERPINE1/PAI-1) have been reported in patients with hepatocellular carcinoma (HCC) associated with viral infection. The gene encoding SERPINE1 is highly polymorphic and the frequently associated 4/5 guanosine (4G/5G) polymorphism in the gene promoter may influence its expression. Here, we investigated the distribution of genotypes and the frequency of alleles of the 4G/5G polymorphism in patients with HCC, the influence of the 4G/5G polymorphism on plasma SERPINE1 levels and its association with viral infection. A total of 75 patients with HCC were enrolled: 32 (42.6%) were HBV(+)/HCV(+), 11 (14.6%) were only HCV(+), and 32 (42.6%) were negative for both viruses. A control group of healthy donors was also enrolled (n=50). SERPINE1 plasma concentrations were determined by ELISA and the detection of the promoter 4G/5G polymorphism was performed by an allele-specific PCR analysis. We found that the frequency of both the 4G/4G genotype (p=0.02) and the 4G allele (p=0.006) were significantly higher in patients with HCC compared to the control group, and particularly higher in patients with HCC co-infected with HBV(+)/HCV(+) than in those with no viral infection. We also found that patients with the 4G/4G genotype had significantly higher plasma SERPINE1 protein levels when compared with patients with the 4G/5G or 5G/5G genotype (p<0.001). Differences in frequency of 4G allele and genetic variability of 4G/5G SERPINE1 polymorphism with a higher level of SERPINE1 protein in patients with HCC with HBV(+)/HCV(+) than those without infection, suggest the presence of two distinct pathogenic mechanisms in hepatocarcinogenesis, depending on the etiology.
Analysis on the time and frequency domains of the acceleration in front crawl stroke.
Gil, Joaquín Madera; Moreno, Luis-Millán González; Mahiques, Juan Benavent; Muñoz, Víctor Tella
2012-05-01
The swimming involves accelerations and decelerations in the swimmer's body. Thus, the main objective of this study is to make a temporal and frequency analysis of the acceleration in front crawl swimming, regarding the gender and the performance. The sample was composed by 31 male swimmers (15 of high-level and 16 of low-level) and 20 female swimmers (11 of high-level and 9 of low-level). The acceleration was registered from the third complete cycle during eight seconds in a 25 meters maximum velocity test. A position transducer (200Hz) was used to collect the data, and it was synchronized to an aquatic camera (25Hz). The acceleration in the temporal (root mean square, minimum and maximum of the acceleration) and frequency (power peak, power peak frequency and spectral area) domains was calculated with Fourier analysis, as well as the velocity and the spectrums distribution in function to present one or more main peaks (type 1 and type 2). A one-way ANOVA was used to establish differences between gender and performance. Results show differences between genders in all the temporal domain variables (p<0.05) and only the Spectral Area (SA) in the frequency domain (p<0.05). Between gender and performance, only the Root Mean Square (RMS) showed differences in the performance of the male swimmers (p<0.05) and in the higher level swimmers, the Maximum (Max) and the Power Peak (PP) of the acceleration showed differences between both genders (p<0.05). These results confirms the importance of knowing the RMS to determine the efficiency of the swimmers regarding gender and performance level.
Pavanello, Sofia; Kapka, Lucyna; Siwinska, Ewa; Mielzyñska, Danuta; Bolognesi, Claudia; Clonfero, Erminio
2008-10-01
Micronuclei (MN) frequency associated to biologically effective dose of polycyclic aromatic hydrocarbons [PAH; anti-benzo[a]pyrene diolepoxide (B[a]PDE)-DNA] within the same subjects' peripheral blood lymphocytes (PBL) was evaluated. Study subjects were nonsmoking male Polish coke-oven workers (n=49) and matched controls (n=45) verified for PAH exposure by urinary 1-pyrenol. We found that coke-oven workers, heavily exposed to PAHs (80% workers exceeded the urinary 1-pyrenol biological exposure index value), presented significantly higher MN frequency in PBLs than controls (P<0.01). Substantial difference was also found for adduct levels in PBLs (P<0.01). Increase in MN levels was significantly related to anti-B[a]PDE-DNA formation, key adduct of the ultimate carcinogenic metabolite of B[a]P (n=94; r=0.47; P<0.001). The dose-response relationship was improved when subjects with adduct levels above the 3rd tertile (>or=4.35 adducts/10(8) nucleotides) were excluded (n=61; r=0.69; P<0.001). Saturation of adduct/MN formation at high levels may disturb the underlying relationship. Linear multiple regression analysis, without subjects of 3rd tertile adduct level (n=61), revealed that adduct formation (t=4.61; P<0.001), but not 1-pyrenol, was the significant determinant in increasing MN. In conclusion, the increase in MN frequency is mainly related to the specific anti-B[a]PDE-DNA formation within PBLs of the same subject. Our results substantiate, with the use of an early indicator of biological effect as well, that workers are at higher cancer risk than controls.
Frequency-domain method for discrete frequency noise prediction of rotors in arbitrary steady motion
NASA Astrophysics Data System (ADS)
Gennaretti, M.; Testa, C.; Bernardini, G.
2012-12-01
A novel frequency-domain formulation for the prediction of the tonal noise emitted by rotors in arbitrary steady motion is presented. It is derived from Farassat's 'Formulation 1A', that is a time-domain boundary integral representation for the solution of the Ffowcs-Williams and Hawkings equation, and represents noise as harmonic response to body kinematics and aerodynamic loads via frequency-response-function matrices. The proposed frequency-domain solver is applicable to rotor configurations for which sound pressure levels of discrete tones are much higher than those of broadband noise. The numerical investigation concerns the analysis of noise produced by an advancing helicopter rotor in blade-vortex interaction conditions, as well as the examination of pressure disturbances radiated by the interaction of a marine propeller with a non-uniform inflow.
Accuracy of assessing the level of impulse sound from distant sources.
Wszołek, Tadeusz; Kłaczyński, Maciej
2007-01-01
Impulse sound events are characterised by ultra high pressures and low frequencies. Lower frequency sounds are generally less attenuated over a given distance in the atmosphere than higher frequencies. Thus, impulse sounds can be heard over greater distances and will be more affected by the environment. To calculate a long-term average immission level it is necessary to apply weighting factors like the probability of the occurrence of each weather condition during the relevant time period. This means that when measuring impulse noise at a long distance it is necessary to follow environmental parameters in many points along the way sound travels and also to have a database of sound transfer functions in the long term. The paper analyses the uncertainty of immission measurement results of impulse sound from cladding and destroying explosive materials. The influence of environmental conditions on the way sound travels is the focus of this paper.
Plume RF interference calculations for space shuttle
NASA Technical Reports Server (NTRS)
Boynton, F. P.; Rajasekhar, P. S.
1978-01-01
During a static ground test of a full-scale SRM, measurements of attenuation of the UHF 416.5 MHz Range Safety Signal, the VHF voice link (230 MHz), and of S-band (c. 2.2. GHz) communications links were undertaken. Analyses of these results indicate that measurable attenuation did occur at all test frequencies. The measured attenuation levels are compared with a simple model in which the received signal is identified as that diffracted about the edge of the highly absorbing plume and the signal level in the shadow zone is evaluated using the formula for diffraction at a straight edge. The comparison is satisfactory at VHF and UHF frequencies, and slightly less so at S-band. Reasons for the discrepancies found at higher frequencies are discussed. A revised procedure which appears to relieve the accuracy problem was developed. This procedure is discussed along with applications to high altitude SRM plume attenuation.
Tavakkolizadeh, Moein; Love‐Jones, Sarah; Patel, Nikunj K.; Gu, Jianwen Wendy; Bains, Amarpreet; Doan, Que; Moffitt, Michael
2017-01-01
Objective The PROCO RCT is a multicenter, double‐blind, crossover, randomized controlled trial (RCT) that investigated the effects of rate on analgesia in kilohertz frequency (1–10 kHz) spinal cord stimulation (SCS). Materials and Methods Patients were implanted with SCS systems and underwent an eight‐week search to identify the best location (“sweet spot”) of stimulation at 10 kHz within the searched region (T8–T11). An electronic diary (e‐diary) prompted patients for pain scores three times per day. Patients who responded to 10 kHz per e‐diary numeric rating scale (ED‐NRS) pain scores proceeded to double‐blind rate randomization. Patients received 1, 4, 7, and 10 kHz SCS at the same sweet spot found for 10 kHz in randomized order (four weeks at each frequency). For each frequency, pulse width and amplitude were titrated to optimize therapy. Results All frequencies provided equivalent pain relief as measured by ED‐NRS (p ≤ 0.002). However, mean charge per second differed across frequencies, with 1 kHz SCS requiring 60–70% less charge than higher frequencies (p ≤ 0.0002). Conclusions The PROCO RCT provides Level I evidence for equivalent pain relief from 1 to 10 kHz with appropriate titration of pulse width and amplitude. 1 kHz required significantly less charge than higher frequencies. PMID:29220121
Human perceptual overestimation of whole body roll tilt in hypergravity
Newman, Michael C.; Oman, Charles M.; Merfeld, Daniel M.; Young, Laurence R.
2014-01-01
Hypergravity provides a unique environment to study human perception of orientation. We utilized a long-radius centrifuge to study perception of both static and dynamic whole body roll tilt in hypergravity, across a range of angles, frequencies, and net gravito-inertial levels (referred to as G levels). While studies of static tilt perception in hypergravity have been published, this is the first to measure dynamic tilt perception (i.e., with time-varying canal stimulation) in hypergravity using a continuous matching task. In complete darkness, subjects reported their orientation perception using a haptic task, whereby they attempted to align a hand-held bar with their perceived horizontal. Static roll tilt was overestimated in hypergravity, with more overestimation at larger angles and higher G levels, across the conditions tested (overestimated by ∼35% per additional G level, P < 0.001). As our primary contribution, we show that dynamic roll tilt was also consistently overestimated in hypergravity (P < 0.001) at all angles and frequencies tested, again with more overestimation at higher G levels. The overestimation was similar to that for static tilts at low angular velocities but decreased at higher angular velocities (P = 0.006), consistent with semicircular canal sensory integration. To match our findings, we propose a modification to a previous Observer-type canal-otolith interaction model. Specifically, our data were better modeled by including the hypothesis that the central nervous system treats otolith stimulation in the utricular plane differently than stimulation out of the utricular plane. This modified model was able to simulate quantitatively both the static and the dynamic roll tilt overestimation in hypergravity measured experimentally. PMID:25540216
Subharmonic and fundamental high amplitude excitation of an axisymmetric jet
NASA Technical Reports Server (NTRS)
Raman, Ganesh; Rice, Edward J.
1989-01-01
A circular jet was excited simultaneously by two different harmonically related tones. Data for three pairs of Strouhal numbers (St(D) = f*D/U (sub j) = 0.2 and 0.4, 0.3 and 0.6, 0.4 and 0.8). For each case the initial phase difference between the two waves was varied in steps of 45 deg, for one full cycle and the level of the fundamental and subharmonic forcing were varied independently over the range of 0.1 to 7 percent of the jet exit velocity. Our initial findings concurred with published findings, such as a critical level of the fundamental is required for subharmonic augmentation, the initial phase difference is critical in determining whether the subharmonic is augmented or suppressed. The detailed documentation of several aspects of this phenomenon all measured in one and the same experimental facility in a controlled manner, bring out several important points that eluded previous researchers: (1) At high amplitudes of the fundamental and subharmonic forcing levels the subharmonic augmentation is independent of the initial phase difference. (2) Contrary to the earlier belief that stable pairing could be produced only with an initial laminar boundary layer, the present work shows that by the two-frequency excitation method this phenomenon can be induced over a range of conditions for a jet with an initially turbulent boundary layer. (3) It is seen that two-frequency excitation is indeed more effective than single frequency excitation in jet mixing enhancement. Higher spreading rates seem to go along with higher subharmonic levels.
NASA Astrophysics Data System (ADS)
Howard, Mackenzie A.; Stagner, Barden B.; Lonsbury-Martin, Brenda L.; Martin, Glen K.
2002-01-01
Distortion-product otoacoustic emissions (DPOAEs) at 2f1-f2 can be suppressed by the introduction of a third ``suppressor'' tone. Plotting the suppression of the DPOAE level against the changing frequency and level of the suppressor produces frequency-tuning functions referred to as suppression tuning curves (STCs). The dominant features of STCs, including their shape, are similar to the features of neural tuning curves (NTCs) recorded from single auditory nerve fibers. However, recent findings using reversible diuretics suggest that STCs do not provide the same measure of cochlear frequency selectivity as provided by NTCs. To determine if STCs are also insensitive to the adverse effects of excessive sounds, the present study exposed rabbits to a moderate-level noise that produced temporary threshold shift-like (TTS) effects on DPOAEs, and examined the influence of such exposures on STCs. DPOAEs were produced using primary tones with geometric-mean frequencies centered at 2.8 or 4 kHz, and with L1 and L2 values of 45/45, 50/35, 50/50, and 55/45 dB SPL. STCs were obtained before and during recovery for a period of approximately 2 h immediately following, and at 1, 2, 3, and 7 d post-exposure to a 2 kHz octave band noise, at levels and durations sufficient to cause significant but reversible reductions in DPOAE levels. STC data included tip center frequency, tip threshold, and Q10dB measures of tuning for suppression criteria of 3, 6, 9, and 12 dB. Recovery was variable between animals, but all rabbits recovered fully by 7 d post-exposure. STC center frequencies measured during the TTS typically tuned to a slightly higher frequency, while tip thresholds tended to decrease and Q10dB increase. Together, the results indicate that, despite similarities in the general properties of STCs and NTCs, these two types of tuning curves are affected differently following reversible cochlear insult.
Kobayashi, Satomi; Asakura, Keiko; Suga, Hitomi; Sasaki, Satoshi
2017-06-01
Living status (e.g., living with family or alone) may affect dietary habits. We compared nutritional adequacy according to living status and the frequency of eating out-of-home foods in young Japanese women. Female dietetic students (aged 18-20 years; n = 4,017) participated in a cross-sectional multicenter study, which was conducted in 85 dietetic schools in 35 of 47 prefectures in Japan. Habitual dietary intake was assessed with a validated diet history questionnaire. Nutritional adequacy was determined based on the Dietary Reference Intakes for Japanese, 2015, for two goals: preventing non-communicable chronic disease (a tentative dietary goal for preventing lifestyle-related diseases [DG] that tracks five nutrients) and avoiding insufficient intake of mainly vitamins and minerals (estimated average requirement [EAR] that tracks 14 nutrients). Women living with their family were less likely to meet DG nutrient levels, but more likely to meet EAR nutrient levels compared with those living alone. In contrast, women living alone had more inadequate nutrients with EAR and fewer nutrients with not-meeting DG than those living with families. A higher frequency of eating out-of-home was significantly associated with a higher prevalence of not-meeting DG nutrient levels only in the women living with their family. The prevalence of nutritional adequacy varied based on living status. In addition, women living with their family and those with a high frequency of eating out-of-home foods had the highest prevalence of not-meeting DG. Effective ways of improving dietary quality among young Japanese women differ by living status. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Magari, Masaki; Kanehiro, Yuichi; Todo, Kagefumi
Chicken B cell line DT40 continuously accumulates mutations in the immunoglobulin variable region (IgV) gene by gene conversion and point mutation, both of which are mediated by activation-induced cytidine deaminase (AID), thereby producing an antibody (Ab) library that is useful for screening monoclonal Abs (mAbs) in vitro. We previously generated an engineered DT40 line named DT40-SW, whose AID expression can be reversibly switched on or off, and developed an in vitro Ab generation system using DT40-SW cells. To efficiently create an Ab library with sufficient diversity, higher hypermutation frequency is advantageous. To this end, we generated a novel cell linemore » DT40-SW{Delta}C, which conditionally expresses a C-terminus-truncated AID mutant lacking the nuclear export signal. The transcription level of the mutant AID gene in DT40-SW{Delta}C cells was similar to that of the wild-type gene in DT40-SW cells. However, the protein level of the truncated AID mutant was less than that of the wild type. The mutant protein was enriched in the nuclei of DT40-SW{Delta}C cells, although the protein might be highly susceptible to degradation. In DT40-SW{Delta}C cells, both gene conversion and point mutation occurred in the IgV gene with over threefold higher frequency than in DT40-SW cells, suggesting that a lower level of the mutant AID protein was sufficient to increase mutation frequency. Thus, DT40-SW{Delta}C cells may be useful for constructing Ab libraries for efficient screening of mAbs in vitro.« less
Influence of HLA-C Expression Level on HIV Control
Apps, Richard; Qi, Ying; Carlson, Jonathan M.; Chen, Haoyan; Gao, Xiaojiang; Thomas, Rasmi; Yuki, Yuko; Del Prete, Greg Q.; Goulder, Philip; Brumme, Zabrina L.; Brumme, Chanson J.; John, Mina; Mallal, Simon; Nelson, George; Bosch, Ronald; Heckerman, David; Stein, Judy L.; Soderberg, Kelly A.; Moody, M. Anthony; Denny, Thomas N.; Zeng, Xue; Fang, Jingyuan; Moffett, Ashley; Lifson, Jeffrey D.; Goedert, James J.; Buchbinder, Susan; Kirk, Gregory D.; Fellay, Jacques; McLaren, Paul; Deeks, Steven G.; Pereyra, Florencia; Walker, Bruce; Michael, Nelson L.; Weintrob, Amy; Wolinsky, Steven; Liao, Wilson; Carrington, Mary
2013-01-01
A variant upstream of human leukocyte antigen C (HLA-C) shows the most significant genome-wide effect on HIV control in European Americans and is also associated with the level of HLA-C expression. We characterized the differential cell surface expression levels of all common HLA-C allotypes and tested directly for effects of HLA-C expression on outcomes of HIV infection in 5243 individuals. Increasing HLA-C expression was associated with protection against multiple outcomes independently of individual HLA allelic effects in both African and European Americans, regardless of their distinct HLA-C frequencies and linkage relationships with HLA-B and HLA-A. Higher HLA-C expression was correlated with increased likelihood of cytotoxic T lymphocyte responses and frequency of viral escape mutation. In contrast, high HLA-C expression had a deleterious effect in Crohn’s disease, suggesting a broader influence of HLA expression levels in human disease. PMID:23559252
Salvo, Vera Lúcia Morais Antonio de; Cardoso, Marly Augusto; Barros Junior, Newton de; Ferreira, Sandra R G; Gimeno, Suely Godoy Agostinho
2009-10-01
To describe the food intake of Japanese-Brazilians with and without macrovascular disease (MVD). MVD was defined, for 1,165 Japanese-Brazilians, by scores attributed to the health historical, electrocardiogram and ankle-brachial index values. The usual dietary intake was determined using a food frequency questionnaire. The MVD prevalence was of 3.2%, being similar among genders. Statistically higher frequencies of individuals with MVD were observed among those of first generation, with age > 60 years, tobacco user, with hypertension, hypertriglyceridemia and diabetes. Subjects with MVD were older, with smaller hip circumference, and higher systolic blood pressure levels, triglycerides and glycemia concentration; they informed higher consumption of iron source food and smaller of grains fibers. Statistically significant difference was found to saturated fat (crude analysis: second tercile versus first tercile). Programs of nutritional education should be stimulated in this group with high prevalence of non-communicable chronic diseases.
How wind turbines affect the performance of seismic monitoring stations and networks
NASA Astrophysics Data System (ADS)
Neuffer, Tobias; Kremers, Simon
2017-12-01
In recent years, several minor seismic events were observed in the apparently aseismic region of the natural gas fields in Northern Germany. A seismic network was installed in the region consisting of borehole stations with sensor depths up to 200 m and surface stations to monitor induced seismicity. After installation of the network in 2012, an increasing number of wind turbines was established in proximity (<5 km) to several stations, thereby influencing the local noise conditions. This study demonstrates the impact of wind turbines on seismic noise level in a frequency range of 1-10 Hz at the monitoring sites with correlation to wind speed, based on the calculation of power spectral density functions and I95 values of waveforms over a time period of 4 yr. It could be shown that higher wind speeds increase the power spectral density amplitudes at distinct frequencies in the considered frequency band, depending on height as well as number and type of influencing wind turbines. The azimuthal direction of incoming Rayleigh waves at a surface station was determined to identify the noise sources. The analysis of the perturbed wave field showed that Rayleigh waves with backazimuths pointing to wind turbines in operation are dominating the wave field in a frequency band of 3-4 Hz. Additional peaks in a frequency range of 1-4 Hz could be attributed to turbine tower eigenfrequencies of various turbine manufactures with the hub height as defining parameter. Moreover, the influence of varying noise levels at a station on the ability to automatically detect seismic events was investigated. The increased noise level in correlation to higher wind speeds at the monitoring sites deteriorates the station's recording quality inhibiting the automatic detection of small seismic events. As a result, functionality and task fulfilment of the seismic monitoring network is more and more limited by the increasing number of nearby wind turbines.
Pasalich, Dave S; Dadds, Mark R; Vincent, Lucy C; Cooper, Francesca A; Hawes, David J; Brennan, John
2012-01-01
This study examined relationships between parent-child emotional communication and callous-unemotional (CU) traits and conduct problems. References to negative and positive emotions made by clinic-referred boys (3-9 years) and their parents were coded from direct observations of family interactions involving the discussion of shared emotional experiences. Although frequencies of parents' emotion expression did not generally relate to levels of CU traits, boys higher on CU traits were observed to be more expressive of negative emotions in conversation with their caregivers-specifically for sadness and fear. Independent coders did not judge these children to be less genuine in their emotion expression compared to their low-CU counterparts. We also examined whether CU traits moderated the relationship between parents' focus on emotions and conduct problem severity. Higher levels of maternal focus on negative emotions were found to be associated with lower conduct problems in high-CU boys but related to higher conduct problems in low-CU boys. Frequencies of fathers' emotional communication were unrelated to either child CU traits or conduct problems. We discuss the implications of these findings for the conceptualization of CU traits in preadolescent children, and interventions for conduct problems in children elevated on these traits.
Properies of the microseism wave field in Australia from three component array data
NASA Astrophysics Data System (ADS)
Gal, Martin; Reading, Anya; Ellingsen, Simon; Koper, Keith; Burlacu, Relu; Tkalčić, Hrvoje
2016-04-01
In the last two decades, ambient noise studies in the range of 1-20 seconds have predominantly focused on the analysis of source regions for Rayleigh and P waves. The theoretical excitation of these phases is well understood for primary microseisms (direct coupling of gravity waves in sloping shallow bathymetry) and secondary microseisms (wave-wave interaction) and correlates well with observations. For Love waves, the excitation mechanism in the secondary microseism band is to date unknown. It has been shown, that LQ waves can exhibit larger amplitudes than Rg waves for certain frequencies. Therefore detailed analysis of the wave field are necessary to find indications on the generation mechanism. We analyse data from two spiral-shaped arrays located in Australia, the Pilbara Array (PSAR) in the North-West and an array in South Queensland (SQspa) in the East. The two arrays are different in aperture and allow for the study of primary and secondary microseisms with SQspa and higher secondary microseisms with PSAR. We use a deconvolution enhanced beamforming approach, which is based on the CLEAN algorithm. It allows the accurate detection of weaker sources and the estimation of power levels on each component or wave type. For PSAR we evaluate 1 year of data in the frequency range of 0.35-1 Hz and find fundamental and higher mode Rg and LQ waves. For the low end of the frequency range, we find the strongest fundamental mode Rg waves to originate from multiple direction, but confined to coastline reflectors, i.e. coastlines that are perpendicular to the main swell direction, while higher mode Rg waves are mainly generated in the Great Australian Bight. For higher frequencies, the source locations of Rg waves move toward the north coast, which is closest to the array and we see an increase in the Lg phase. The majority of fundamental LQ waves are generated at the west coast of Australia and we find some agreement between low frequency Rg and LQ source locations, which becomes uncorrelated with increasing frequency. For higher mode LQ waves the generation region is in the south-west, where Australia is exposed to direct swells from the Antarctic. In the case of Rg-to-LQ power ratio, we find a frequency and backazimuth dependence. Results from SQspa allow lower frequency arrivals around the primary and secondary microseism peak to be investigated.
Burns, John W; Quartana, Phillip J; Bruehl, Stephen; Janssen, Imke; Dugan, Sheila A; Appelhans, Bradley; Matthews, Karen A; Kravitz, Howard M
2015-04-01
Chronic pain may be related to cardiovascular disease (CVD) risk. The current study examined whether persistent bodily pain was related to cardiovascular disease risk factors, whether these effects were moderated by body mass index (BMI), and, if not, whether chronic pain accounted for unique variance in CVD risk factors. Participants were women (N = 2,135) in the Study of Women's Health Across the Nation. A high pain frequency variable (high pain in 0 through 4 assessments) was coded to reflect the frequency of high levels of bodily pain across the first 3 years of the study. Six CVD risk factors and BMI were measured at follow-up year 3. High pain frequency and BMI were correlated significantly with risk factors, although effects for the former were small. Hierarchical multiple regressions revealed high pain frequency × BMI interactions for 5 of 6 CVD risk factors. Dissecting the interactions revealed a similar pattern across 4 risk factors: for women with normal BMI, there was a "dose-response" in which increasing frequency of high pain revealed increasingly worse CVD risk factor levels, whereas for women with obese BMI, high pain frequency was unrelated to risk factors. For obese women, increasing frequency of high pain was associated with higher blood glucose. Although BMI is a well-established CVD risk factor, evaluation of CVD risk level may be improved by considering the incidence of persistent pain, particularly in normal weight women (BMI < 25 kg/m(2)) lower BMI.
Task and spatial frequency modulations of object processing: an EEG study.
Craddock, Matt; Martinovic, Jasna; Müller, Matthias M
2013-01-01
Visual object processing may follow a coarse-to-fine sequence imposed by fast processing of low spatial frequencies (LSF) and slow processing of high spatial frequencies (HSF). Objects can be categorized at varying levels of specificity: the superordinate (e.g. animal), the basic (e.g. dog), or the subordinate (e.g. Border Collie). We tested whether superordinate and more specific categorization depend on different spatial frequency ranges, and whether any such dependencies might be revealed by or influence signals recorded using EEG. We used event-related potentials (ERPs) and time-frequency (TF) analysis to examine the time course of object processing while participants performed either a grammatical gender-classification task (which generally forces basic-level categorization) or a living/non-living judgement (superordinate categorization) on everyday, real-life objects. Objects were filtered to contain only HSF or LSF. We found a greater positivity and greater negativity for HSF than for LSF pictures in the P1 and N1 respectively, but no effects of task on either component. A later, fronto-central negativity (N350) was more negative in the gender-classification task than the superordinate categorization task, which may indicate that this component relates to semantic or syntactic processing. We found no significant effects of task or spatial frequency on evoked or total gamma band responses. Our results demonstrate early differences in processing of HSF and LSF content that were not modulated by categorization task, with later responses reflecting such higher-level cognitive factors.
Zhang, Xiao; Duan, Huawei; Gao, Feng; Li, Yuanyuan; Huang, Chuanfeng; Niu, Yong; Gao, Weimin; Yu, Shanfa; Zheng, Yuxin
2015-02-01
The International Agency for Research on Cancer has recently reclassified diesel engine exhaust (DEE) as a Group 1 carcinogen. Micronucleus (MN), nucleoplasmic bridge (NPB), and nuclear bud (NBUD) frequencies in peripheral blood lymphocytes (PBLs) are associated with cancer risk. However, the impact of DEE exposure on MN frequency has not been thoroughly elucidated due to mixed exposure and its impact on NPB and NBUD frequencies has never been explored in humans. We recruited 117 diesel engine testing workers with exclusive exposure to DEE and 112 non-DEE-exposed workers, and then we measured urinary levels of 4 mono-hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) using high-performance liquid chromatography-mass spectrometry as well as MN, NPB, and NBUD frequencies in PBLs using cytokinesis-block MN assay. The DEE-exposed workers exhibited significantly higher MN, NPB, and NBUD frequencies than the non-DEE-exposed workers (P < 0.05). Among all study subjects, increasing levels of all 4 urinary OH-PAHs, on both quartile and continuous scales, were associated with increased MN, NPB, and NBUD frequencies (all P < 0.05). When the associations were analyzed separately in DEE-exposed and non-DEE-exposed workers, we found that the association between increasing quartiles of urinary 9-hydroxyphenanthrene (9-OHPh) and MN frequencies persisted in DEE-exposed workers (P = 0.001). The percent of MN frequencies increased, on average, by 23.99% (95% confidential interval, 9.64-39.93) per 1-unit increase in ln-transformed 9-OHPh. Our results clearly show that exposure to DEE can induce increases in MN, NPB, and NBUD frequencies in PBLs and suggest that DEE exposure level is associated with MN frequencies. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
NF-kappa B activation correlates with disease phenotype in Crohn’s disease
Han, Yoo Min; Koh, Jaemoon; Lee, Changhyun; Koh, Seong-Joon; Kim, ByeongGwan; Lee, Kook Lae; Im, Jong Pil; Kim, Joo Sung
2017-01-01
Background/Aims Unregulated activation of nuclear factor-κB (NF-κB) plays a critical role in the pathogenesis of Crohn’s disease. In this study, we investigated the clinical characteristics and disease outcome of Crohn’s disease patients with varying levels of the NF-κB activation. Methods Crohn’s disease patients who underwent surgical bowel resection were divided into two groups, based on the activation status of NF-κB. NF-κB activation was assessed by the immunoreactivity of nuclear NF-κB during immunohistochemical staining of bowel resection specimens. We compared the demographic, clinical and histologic characteristics between groups. Furthermore, the occurrence of reoperation, readmission, and medication change due to disease flare-up were investigated according to NF-κB activation status. Results Among 83 Crohn’s disease patients, 47 (56%) showed high NF-κB activity and 36 (44%) showed low NF-κB activity. Patients with high NF-κB activity had higher frequency of ileocolonic involvement (P = 0.028) and lower frequency of perianal involvement (P = 0.042) relative to those with low NF-κB activity. Total histologic scores were significantly higher in patients with high NF-κB activity than those with low NF-κB activity (P = 0.044). There was no significant difference in the frequency of reoperation, readmission, and medication change in relation to NF-κB activation status. Conclusions Crohn’s disease patients with high NF-κB activation showed specific clinical manifestations of higher frequency of ileocolonic involvement and lower frequency of perianal involvement relative to those with low NF-κB activation. High NF-κB activity was associated with higher histologic scores. However, the NF-κB activity did not affect the outcome and disease course after surgery. PMID:28753650
Patient satisfaction after pulmonary resection for lung cancer: a multicenter comparative analysis.
Pompili, Cecilia; Brunelli, Alessandro; Rocco, Gaetano; Salvi, Rosario; Xiumé, Francesco; La Rocca, Antonello; Sabbatini, Armando; Martucci, Nicola
2013-01-01
Patient satisfaction reflects the perception of the customer about the level of quality of care received during the episode of hospitalization. To compare the levels of satisfaction of patients submitted to lung resection in two different thoracic surgical units. Prospective analysis of 280 consecutive patients submitted to pulmonary resection for neoplastic disease in two centers (center A: 139 patients; center B: 141 patients; 2009-2010). Patients' satisfaction was assessed at discharge through the EORTC-InPatSat32 module, a 32-item, multi-scale self-administered anonymous questionnaire. Each scale (ranging from 0 to 100 in score) was compared between the two units. Multivariable regression and bootstrap were used to verify factors associated with the patients' general satisfaction (dependent variable). Patients from unit B reported a higher general satisfaction (91.5 vs. 88.3, p = 0.04), mainly due to a significantly higher satisfaction in the doctor-related scales (doctors' technical skill: p = 0.001; doctors' interpersonal skill: p = 0.008; doctors' availability: p = 0.005, and doctors information provision: p = 0.0006). Multivariable regression analysis and bootstrap confirmed that level of care in unit B (p = 0.006, bootstrap frequency 60%) along with lower level of education of the patient population (p = 0.02, bootstrap frequency 62%) were independent factors associated with a higher general patient satisfaction. We were able to show a different level of patient satisfaction in patients operated on in two different thoracic surgery units. A reduced level of patient satisfaction may trigger changes in the management policy of individual units in order to meet patients' expectations and improve organizational efficiency. Copyright © 2012 S. Karger AG, Basel.
Gianella, Sara; Morris, Sheldon R; Anderson, Christy; Spina, Celsa A; Vargas, Milenka V; Young, Jason A; Richman, Douglas D; Little, Susan J; Smith, Davey M
2013-01-02
To further understand the role that chronic viral infections of the male genital tract play on HIV-1 dynamics and replication. Retrospective, observational study including 236 paired semen and blood samples collected from 115 recently HIV-1 infected antiretroviral naive men who have sex with men. In this study, we evaluated the association of seminal HIV-1 shedding to coinfections with seven herpes viruses, blood plasma HIV-1 RNA levels, CD4 T-cell counts, presence of transmitted drug resistance mutations (DRMs) in HIV-1 pol, participants' age and stage of HIV-infection using multivariate generalized estimating equation methods. Associations between herpes virus shedding, seminal HIV-1 levels, number and immune activation of seminal T-cells was also investigated (Mann-Whitney). Seminal herpes virus shedding was observed in 75.7% of individuals. Blood HIV-1 RNA levels (P < 0.01) and seminal cytomegalovirus (CMV) and human herpes virus (HHV)-8 levels (P < 0.05) were independent predictors of detectable seminal HIV-1 RNA; higher seminal HIV-1 levels were associated with CMV and Epstein-Barr virus (EBV) seminal shedding, and absence of DRM (P < 0.05). CMV and EBV seminal shedding was associated with higher number of seminal T-lymphocytes, but only presence of seminal CMV DNA was associated with increased immune activation of T-lymphocytes in semen and blood. Despite high median CD4 T-cells numbers, we found a high frequency of herpes viruses seminal shedding in our cohort. Shedding of CMV, EBV and HHV-8 and absence of DRM were associated with increased frequency of HIV-1 shedding and/or higher levels of HIV-1 RNA in semen, which are likely important cofactors for HIV-1 transmission.
Potential motivational information encoded within humpback whale non-song vocal sounds.
Dunlop, Rebecca A
2017-03-01
Acoustic signals in terrestrial animals follow motivational-structural rules to inform receivers of the signaler's motivational state, valence and level of arousal. Low-frequency "harsh" signals are produced in aggressive contexts, whereas high-frequency tonal sounds are produced in fearful/appeasement contexts. Using the non-song social call catalogue of humpback whales (Megaptera novaeangliae), this study tested for potential motivational-structural rules within the call catalogue of a baleen whale species. A total of 32 groups within different social contexts (ranging from stable, low arousal groups, such as a female with her calf, to affiliating, higher arousal, groups containing multiple males competing for access to the central female) were visually and acoustically tracked as they migrated southwards along the eastern coast of Australia. Social calls separated into four main cluster types, with signal structures in two categories consistent with "aggressive" signals and, "fearful/appeasement" signals in terrestrial animals. The group's use of signals within these clusters matched their context in that presumed low arousal non-affiliating groups almost exclusively used "low-arousal" signals (a cluster of low frequency unmodulated or upsweep sounds). Affiliating groups used a higher proportion of an intermediate cluster of signal types deemed "higher arousal" signals and groups containing three or more adults used a higher proportion of "aggressive" signal types.
High Levels of IL-10 and CD4+CD25hi+ Treg Cells in Endemic Burkitt’s Lymphoma Patients
Futagbi, Godfred; Gyan, Ben; Nunoo, Harriet; Tetteh, John K.A.; Welbeck, Jennifer E.; Renner, Lorna Awo; Ofori, Michael; Dodoo, Daniel; Edoh, Dominic A.; Akanmori, Bartholomew D.
2015-01-01
Background: The interplay between Epstein-Barr virus infection, malaria, and endemic Burkitt’s Lymphoma is not well understood. Reports show diminished EBV-specific Th1 responses in children living in malaria endemic areas and deficiency of EBNA1-specific IFN-γ T cell responses in children with endemic Burkitt’s Lymphoma (eBL). This study, therefore, examined some factors involved in the loss of EBNA-1-specific T cell responses in eBL. Methods: T-cell subset frequencies, activation, and IFN-γ- or IL-4-specific responses were analyzed by flow-cytometry. Plasma cytokine levels were measured by ELISA. Results: CD4+ and CD8+ cells in age- and sex-matched healthy controls (n = 3) expressed more IFN-γ in response to all immunostimulants than in pediatric endemic BL (eBL) patients (n = 4). In healthy controls, IFN-γ expression was higher than IL-4 expression, whereas in eBL patients the expression of IL-4 by CD4+ cells to EBNA-1 was slightly higher than IFN-γ. Moreover, the blood levels of TNF-α was significantly lower (p = 0.004) while IL-10 was significantly higher (p = 0.038), in eBL patients (n = 21) compared to controls (n = 16). Additionally, the frequency of CD4+CD25hi+ T cells was higher in both age-matched acute uncomplicated malaria (n = 26) and eBL (n = 14) patients compared to healthy controls (n = 19; p = 0.000 and p = 0.027, respectively). Conclusion: The data suggest that reduced Th1 response in eBL might be due to increased levels of IL-10 and T reg cells. PMID:28536409
High Levels of IL-10 and CD4+CD25hi+ Treg Cells in Endemic Burkitt's Lymphoma Patients.
Futagbi, Godfred; Gyan, Ben; Nunoo, Harriet; Tetteh, John K A; Welbeck, Jennifer E; Renner, Lorna Awo; Ofori, Michael; Dodoo, Daniel; Edoh, Dominic A; Akanmori, Bartholomew D
2015-08-04
The interplay between Epstein-Barr virus infection, malaria, and endemic Burkitt's Lymphoma is not well understood. Reports show diminished EBV-specific Th1 responses in children living in malaria endemic areas and deficiency of EBNA1-specific IFN-γ T cell responses in children with endemic Burkitt's Lymphoma (eBL). This study, therefore, examined some factors involved in the loss of EBNA-1-specific T cell responses in eBL. T-cell subset frequencies, activation, and IFN-γ- or IL-4-specific responses were analyzed by flow-cytometry. Plasma cytokine levels were measured by ELISA. CD4+ and CD8+ cells in age- and sex-matched healthy controls ( n = 3) expressed more IFN-γ in response to all immunostimulants than in pediatric endemic BL (eBL) patients ( n = 4). In healthy controls, IFN-γ expression was higher than IL-4 expression, whereas in eBL patients the expression of IL-4 by CD4+ cells to EBNA-1 was slightly higher than IFN-γ. Moreover, the blood levels of TNF-α was significantly lower ( p = 0.004) while IL-10 was significantly higher ( p = 0.038), in eBL patients ( n = 21) compared to controls ( n = 16). Additionally, the frequency of CD4+CD25hi+ T cells was higher in both age-matched acute uncomplicated malaria ( n = 26) and eBL ( n = 14) patients compared to healthy controls ( n = 19; p = 0.000 and p = 0.027, respectively). The data suggest that reduced Th1 response in eBL might be due to increased levels of IL-10 and T reg cells.
Base composition and expression level of human genes.
Arhondakis, Stilianos; Auletta, Fabio; Torelli, Giuseppe; D'Onofrio, Giuseppe
2004-01-21
It is well known that the gene distribution is non-uniform in the human genome, reaching the highest concentration in the GC-rich isochores. Also the amino acid frequencies, and the hydrophobicity, of the corresponding encoded proteins are affected by the high GC level of the genes localized in the GC-rich isochores. It was hypothesized that the gene expression level as well is higher in GC-rich compared to GC-poor isochores [Mol. Biol. Evol. 10 (1993) 186]. Several features of human genes and proteins, namely expression level, coding and non-coding lengths, and hydrophobicity were investigated in the present paper. The results support the hypothesis reported above, since all the parameters so far studied converge to the same conclusion, that the average expression level of the GC-rich genes is significantly higher than that of the GC-poor genes.
Moore, Brian C J
2012-09-01
This article reviews a series of studies on the factors influencing sound quality preferences, mostly for jazz and classical music stimuli. The data were obtained using ratings of individual stimuli or using the method of paired comparisons. For normal-hearing participants, the highest ratings of sound quality were obtained when the reproduction bandwidth was wide (55 to 16000 Hz) and ripples in the frequency response were small (less than ± 5 dB). For hearing-impaired participants listening via a simulated five-channel compression hearing aid with gains set using the CAM2 fitting method, preferences for upper cutoff frequency varied across participants: Some preferred a 7.5- or 10-kHz upper cutoff frequency over a 5-kHz cutoff frequency, and some showed the opposite preference. Preferences for a higher upper cutoff frequency were associated with a shallow high-frequency slope of the audiogram. A subsequent study comparing the CAM2 and NAL-NL2 fitting methods, with gains slightly reduced for participants who were not experienced hearing aid users, showed a consistent preference for CAM2. Since the two methods differ mainly in the gain applied for frequencies above 4 kHz (CAM2 recommending higher gain than NAL-NL2), these results suggest that extending the upper cutoff frequency is beneficial. A system for reducing "overshoot" effects produced by compression gave small but significant benefits for sound quality of a percussion instrument (xylophone). For a high-input level (80 dB SPL), slow compression was preferred over fast compression.
Jirik, Vitezslav; Pekarek, Ludek; Janout, Vladimir; Tomaskova, Hana
2012-10-01
Higher levels of exposure to extremely low-frequency magnetic fields (ELF-MF) are associated with a slightly increased risk of childhood leukaemia. Compared with more-developed Western countries, higher exposure levels are evident in the Czech Republic, probably because of the different types of housing. In light of this, we aimed to examine the association between ELF-MF exposure and childhood leukaemia in the Czech Republic. We conducted a paired case-control study. The cases (children with leukaemia) were age- sex- and permanent residence-matched to controls (children without leukaemia). Although this limited potential bias and confounding, it also limited our number of participants. The matched analyses included 79 case-control pairs. No significant association between ELF-MF exposure and childhood leukaemia was observed for exposures over 0.2 μT (odds ratio [OR]=0.93, confidence interval [CI]=0.45-1.93), 0.3 μT (OR=0.77, CI=0.34-1.75), or 0.4 μT (OR=0.9, CI=0.37-2.22). Despite higher levels of exposure in Middle and Eastern Europe, no indication of an association between ELF-MF exposure and childhood leukaemia was determined. This in contrast to the findings of previous studies conducted in different countries. Copyright © 2012 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.
Pettorossi, Vito E; Frondaroli, Adele; Grassi, Silvarosa
2011-04-01
The estrous cycle in female rats influences the basal synaptic responsiveness and plasticity of the medial vestibular nucleus (MVN) neurons through different levels of circulating 17β-estradiol (cE(2)). The aim of this study was to verify, in the female rat, whether cyclic fluctuations of cE(2) influence long-term synaptic effects induced by high frequency afferent stimulation (HFS) in the MVN, since we found that HFS in the male rat induces fast long-term potentiation (fLTP), which depends on the neural synthesis of E(2) (nE(2)) from testosterone (T). We analyzed the field potential (FP) evoked in the MVN by vestibular afferent stimulation, under basal conditions, and after HFS, in brainstem slices of female rats during high levels (proestrus, PE) and low levels (diestrus, DE) of cE(2). Selective blocking agents of converting T enzymes were used. Unlike in the male rat, HFS induced three effects: fLTP through T conversion into E(2), and slow LTP (sLTP) and long-term depression (LTD), through T conversion into DHT. The occurrence of these effects depended on the estrous cycle phase: the frequency of fLTP was higher in DE, and those of sLTP and LTD were higher in PE. Conversely, the basal FP was also higher in PE than in DE.
Role of Depression, Anxiety and Stress in Patients with Oral Lichen Planus: A Pilot Study.
Kalkur, Chaithra; Sattur, Atul Prahlad; Guttal, Kruthika Satyabodh
2015-01-01
Lichen planus is a psychosomatic disease. Higher frequency of psychiatric symptoms, poor quality of life, higher level of anxiety and neuroendocrine and immune dysregulations, all these factors, will enhance the exacerbation of the disease. The present study was to assess depression, anxiety and stress levels in patients with oral lichen planus. The psychometric evaluation using the Depression Anxiety Stress Scale (DASS)-42 questionnaire was carried out, by the same investigator on all members of group 1 (Oral Lichen Planus) and group 2 (Control). DASS-42 questionnaire consists of 42 symptoms divided into three subscales of 14 items: Depression scale, anxiety scale, and stress scale. The Student t test was used to determine statistical difference for both the groups and to evaluate for significant relationships among variables. Psychological assessment using DASS-42 reveals lichen planus patients showed higher frequency of psychiatric co morbidities like depression, anxiety and stress compared to control group. This study has provided evidence that the DASS-42 questionnaire is internally consistent and valid measures of depression, anxiety, and stress. Psychiatric evaluation can be considered for patients with oral lichen planus with routine treatment protocols are recommended. DASS-42 Questionnaire can also be used to determine the level of anxiety, stress and depression in diseases of the oral mucosa like recurrent apthous stomatitis, burning mouth syndrome and TMD disorders.
Barnes, Rachel D; Masheb, Robin M; Grilo, Carlos M
2011-12-01
Preliminary studies of non-clinical samples suggest that purposely attempting to avoid thoughts of food, referred to as food thought suppression, is related to a number of unwanted eating- and weight-related consequences, particularly in obese individuals. Despite possible implications for the treatment of obesity and eating disorders, little research has examined food thought suppression in obese individuals with binge eating disorder (BED). This study compared food thought suppression in 60 obese patients with BED to an age-, gender-, and body mass index (BMI)-matched group of 59 obese persons who do not binge eat (NBO). In addition, this study examined the associations between food thought suppression and eating disorder psychopathology within the BED and NBO groups and separately by gender. Participants with BED and women endorsed the highest levels of food thought suppression. Food thought suppression was significantly and positively associated with many features of ED psychopathology in NBO women and with eating concerns in men with BED. Among women with BED, higher levels of food thought suppression were associated with higher frequency of binge eating, whereas among men with BED, higher levels of food thought suppression were associated with lower frequency of binge eating. Our findings suggest gender differences in the potential significance of food thought suppression in obese groups with and without co-existing binge eating problems. Copyright © 2011 Elsevier Ltd. All rights reserved.
Air pollution and heart rate variability: effect modification by chronic lead exposure.
Park, Sung Kyun; O'Neill, Marie S; Vokonas, Pantel S; Sparrow, David; Wright, Robert O; Coull, Brent; Nie, Huiling; Hu, Howard; Schwartz, Joel
2008-01-01
Outdoor air pollution and lead exposure can disturb cardiac autonomic function, but the effects of both these exposures together have not been studied. We examined whether higher cumulative lead exposures, as measured by bone lead, modified cross-sectional associations between air pollution and heart rate variability among 384 elderly men from the Normative Aging Study. We used linear regression, controlling for clinical, demographic, and environmental covariates. We found graded, significant reductions in both high-frequency and low-frequency powers of heart rate variability in relation to ozone and sulfate across the quartiles of tibia lead. Interquartile range increases in ozone and sulfate were associated respectively, with 38% decrease (95% confidence interval = -54.6% to -14.9%) and 22% decrease (-40.4% to 1.6%) in high frequency, and 38% decrease (-51.9% to -20.4%) and 12% decrease (-28.6% to 9.3%) in low frequency, in the highest quartile of tibia lead after controlling for potential confounders. We observed similar but weaker effect modification by tibia lead adjusted for education and cumulative traffic (residuals of the regression of tibia lead on education and cumulative traffic). Patella lead modified only the ozone effect on heart rate variability. People with long-term exposure to higher levels of lead may be more sensitive to cardiac autonomic dysfunction on high air pollution days. Efforts to understand how environmental exposures affect the health of an aging population should consider both current levels of pollution and history of lead exposure as susceptibility factors.
Ardhuin, Fabrice; Lavanant, Thibaut; Obrebski, Mathias; Marié, Louis; Royer, Jean-Yves; d'Eu, Jean-François; Howe, Bruce M; Lukas, Roger; Aucan, Jerome
2013-10-01
The generation of ultra-low frequency acoustic noise (0.1 to 1 Hz) by the nonlinear interaction of ocean surface gravity waves is well established. More controversial are the quantitative theories that attempt to predict the recorded noise levels and their variability. Here a single theoretical framework is used to predict the noise level associated with propagating pseudo-Rayleigh modes and evanescent acoustic-gravity modes. The latter are dominant only within 200 m from the sea surface, in shallow or deep water. At depths larger than 500 m, the comparison of a numerical noise model with hydrophone records from two open-ocean sites near Hawaii and the Kerguelen islands reveal: (a) Deep ocean acoustic noise at frequencies 0.1 to 1 Hz is consistent with the Rayleigh wave theory, in which the presence of the ocean bottom amplifies the noise by 10 to 20 dB; (b) in agreement with previous results, the local maxima in the noise spectrum support the theoretical prediction for the vertical structure of acoustic modes; and (c) noise level and variability are well predicted for frequencies up to 0.4 Hz. Above 0.6 Hz, the model results are less accurate, probably due to the poor estimation of the directional properties of wind-waves with frequencies higher than 0.3 Hz.
Ling, Bo; Liu, Xiaoli; Zhang, Lihui; Wang, Shaojin
2018-03-13
Dielectric heating including microwave (MW) and radio frequency (RF) energy has been regarded as alternative thermal treatments for food processing. To develop effective rice bran (RB) stabilization treatments based on RF and MW heating, dielectric properties (DPs) with dielectric constant (ε') and loss factor (ε″) of RB samples at frequencies (10-3000 MHz), temperatures (25-100 °C), moisture content (MC, 10.36-24.69% w.b.) and three metal salt levels (0.05-2.00%) were determined by an open-ended coaxial probe and impedance analyzer. Results indicated that both ε' and ε″ of RB samples increased with increasing temperature and MC. The increase rate was greater at higher temperature and moisture levels than at lower levels, especially at frequencies lower than 300 MHz. Cubic order models were developed to best fit the relationship between DPs of RB samples and temperature/MC at five frequencies with R 2 greater than 0.994. Both ε″ and RF heating rate of RB samples increased significantly with added NaCl (2%), KCl (1%) and Na 6 O 18 P 6 (2%). The obtained data are useful in developing computer models and simulating dielectric heating for RB stabilization and may also provide theoretical basis for synergistic stabilization of RB under combined dielectric heating with metal salts.
G Allele of the IGF2 ApaI Polymorphism Is Associated With Judo Status.
Itaka, Toshio; Agemizu, Kenichiro; Aruga, Seiji; Machida, Shuichi
2016-07-01
Itaka, T, Agemizu, K, Aruga, S, and Machida, S. G allele of the IGF2 ApaI polymorphism is associated with judo status. J Strength Cond Res 30(7): 2043-2048, 2016-Previous studies have reported that the insulin-like growth factor 2 (IGF2) ApaI polymorphism is associated with body mass index, fat mass, and grip strength. Competitive judo requires high levels of strength and power. The purpose of this study was to investigate the association between the IGF2 ApaI and ACTN3 R577X polymorphisms and judo status. The subjects were 156 male judo athletes from a top-level university in Japan. They were divided into 3 groups based on their competitive history: international-level athletes, national-level athletes, and others. Genomic DNA was extracted from the saliva of each athlete, and the maximal isometric strength of the trunk muscles and handgrip strength were measured. Genotyping by polymerase chain reaction-restriction fragment length polymorphism was used to detect IGF2 (rs680) and α-actinin-3 (ACTN3) (rs1815739) gene polymorphisms. The genotype frequencies of the 2 gene polymorphisms were compared among the 3 groups of judo athletes and controls. International-level judo athletes showed a higher frequency of the GG + GA genotype of the IGF2 gene than that of the national-level athletes and others. There was an inverse linear correlation between the frequency of the IGF2 AA genotype and level of judo performance (p = 0.041). Back muscle strength relative to height and weight was higher in subjects with the GG + GA genotype than in those with the AA genotype. Conversely, the ACTN3 R577X polymorphism was not associated with judo status. Additionally, no differences were found in back muscle or handgrip strength among the ACTN3 genotypes. In conclusion, the results indicate that the IGF2 gene polymorphism may be associated with judo status.
Alam, K; Silberschmidt, Vadim V
2014-01-01
Bone drilling is widely used in orthopaedics, dental and neurosurgeries for repair and fixation purposes. One of the major concerns in drilling of bone is thermal necrosis that may seriously affect healing at interfaces with fixtures and implants. Ultrasonically-assisted drilling (UAD) is recently introduced as alternative to conventional drilling (CD) to minimize invasiveness of the procedure. This paper studies temperature rise in bovine cortical bone drilled with CD and UAD techniques and their comparison using infrared thermography. A parametric investigation was carried out to evaluate effects of drilling conditions (drilling speed and feed rate) and parameters of ultrasonic vibration (frequency and amplitude) on the temperature elevation in bone. Higher levels of the drilling speed and feed rate were found responsible for generating temperatures above a thermal threshold level in both types of drilling. UAD with frequency below 20 kHz resulted in lower temperature compared to CD with the same drilling parameters. The temperatures generated in cases with vibration frequency exceeding 20 kHz were significantly higher than those in CD for the range of drilling speeds and feed rates. The amplitude of vibration was found to have no significant effect on bone temperature. UAD may be investigated further to explore its benefits over the existing CD techniques.
Dyo, Melissa; Kalowes, Peggy; Devries, Jessica
2016-10-01
To assess moral distress intensity and frequency in adult/paediatric nurses in critical care and non-critical care units; and explore relationships of nurse characteristics and moral distress with intention to leave. A descriptive, correlational design was used to administer an online survey using the Moral Distress Scale to nurses across multiple settings. Intensity and frequency of moral distress and intention to leave current position. The survey response rate was 43% (n=426/1000). Critical care nurses had the highest levels of moral distress intensity and frequency, compared to non-critical care specialties (M=2.5±0.19, p=0.005 for intensity and M=1.6±0.11, p<0.001 for frequency). Moral distress frequency showed a positive relationship with intention to leave a position of employment. Each unit increase in moral distress frequency doubled the odds of intention to leave when adjusting for age, gender, ethnicity and specialty area (p=0.003). Hispanic nurses had significantly higher levels of moral distress intensity (p=0.01). Moral distress is a complex phenomenon requiring further study, particularly with regard to the role of ethnic and cultural differences on perceptions of moral distress. Copyright © 2016 Elsevier Ltd. All rights reserved.
Inner ear involvement in Behçet's disease.
Süslü, Ahmet Emre; Polat, Mualla; Köybaşi, Serap; Biçer, Yusuf Ozgür; Funda, Yasemin Ongun; Parlak, Ali Haydar
2010-06-01
To assess cochlear involvement and hearing loss in patients with Behçet's disease (BD). Forty-two patients with BD and 24 sex and age matched healthy subjects were included in the study. pure-tone audiometry including high frequencies (250-16000Hz) and DPOAE were performed to all participants. Results of the audiological evaluation were compared and correlation between the audiologic status and clinical manifestations of the BD were investigated. Bilateral sensorineural hearing loss was detected in 27 (64.3%) patients. Hearing thresholds were found to be higher in patients with BD at all of the frequencies except at 500Hz when compared to control group (p<0.05). The difference in the hearing levels tend to increase in high frequencies. Compared with control group, distortion products and SNR of the BD patients were lower in all of the tested frequencies (p<0.05) which indicates weaker outer hair cell motility. There was no correlation between the clinical manifestations and the audiological parameters. Even having hearing levels within normal limits in speech frequencies, increased hearing thresholds in high frequencies and decreased signal-noise ratios (SNR) in distortion product otoacoustic emission (DPOAE) indicate a cochlear involvement in patients with BD. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.
Thermal-noise-limited higher-order mode locking of a reference cavity
NASA Astrophysics Data System (ADS)
Zeng, X. Y.; Ye, Y. X.; Shi, X. H.; Wang, Z. Y.; Deng, K.; Zhang, J.; Lu, Z. H.
2018-04-01
Higher-order mode locking has been proposed to reduce the thermal noise limit of reference cavities. By locking a laser to the HG02 mode of a 10-cm long all ULE cavity, and measure its performance with the three-cornered-hat method among three independently stabilized lasers, we demonstrate a thermal noise limited performance of a fractional frequency instability of 4.9E-16. The results match the theoretical models with higher-order optical modes. The achieved laser instability improves the all ULE short cavity results to a new low level.
Influence of atomic densities on propagation property for ultrashort pulses in a two-level medium
NASA Astrophysics Data System (ADS)
Liu, Bingxin; Gong, Shangqing; Song, Xiaohong; Jin, Shiqi
2005-05-01
The influence of atomic densities on the propagation property for ultrashort pulses in a two-level atom (TLA) medium is investigated. With higher atomic densities, the self-induced transparency (SIT) cannot be recovered even for 2? ultrashort pulses. New features such as pulse splitting, red-shift and blue-shift of the corresponding spectra arise, and the component of central frequency gradually disappears.
Hernández, Alba; Paiva, Leiliane; Creus, Amadeu; Quinteros, Domingo; Marcos, Ricard
2014-01-01
Arsenic(III)methyltransferase (AS3MT) has been demonstrated to be the key enzyme in the metabolism of arsenic as it catalyses the methylation of arsenite and monomethylarsonic acid (MMA) to form methylated arsenic species, which have higher toxic and genotoxic potential than the parent compounds. The aim of this study is to evaluate if genetic variation in the AS3MT gene influences arsenic-induced cytogenetic damage, measured by the micronucleus (MN) assay. AS3MT Met287Thr allele frequencies and MN values were determined for 207 subjects working in the copper-mine industry, who were exposed to variable levels of arsenic. The urinary arsenic profile was used as individual biomarker of arsenic exposure. Results indicate that the MN frequencies found in peripheral blood lymphocytes of the exposed population poorly correlate with the levels of total arsenic content in urine. Nevertheless, when workers were classified according to their AS3MT Met287Thr genotypes, significantly higher MN values were observed for those carrying the variant allele [odds ratio (OR), 3.4 (1.6-5.2); P=0.0003)]. To our knowledge, these results are the first to show that genetic variation in AS3MT, especially the Met287Thr polymorphism, may play a role in modulating the levels of arsenic-induced cytogenetic damage among individuals chronically exposed to arsenic. Copyright © 2013 Elsevier B.V. All rights reserved.
Media exposure and oral health outcomes among adults.
Zini, Avraham; Sgan-Cohen, Harold D; Vered, Yuval
2013-02-01
To assess the impact of media exposure on oral health outcomes among Jewish adults in Jerusalem, Israel, by means of a conceptual hierarchical model. A cross-sectional study was conducted using a stratified sample of 254 adults 35 to 44 years (mean age, 38.63 years) in Jerusalem, Israel. Media exposure was operationally categorized by type and frequency. Behavioral data included toothbrushing, dental attendance, oral hygiene aids use, plaque level, sugar consumption, and smoking. Clinical outcomes were assessed according to the decayed/missing/filled teeth (DMFT) index and the community periodontal index (CPI). Results were analyzed by chi-square test, independent test, one-way ANOVA, and linear and multiple logistic regression models. A total of 254 examinees consisted of 127 men and 127 mean (married couples). High type and high frequency of media exposure, as compared with other modes, revealed statistically significant higher caries experience (DMFT, 13.10), higher level of untreated decay (D, 1.67), and lower periodontal health (CPI [0], 0.39). A conceptual hierarchical regression model identified that the relationship described was mediated by sociodemographic determinants (education) and behavioral determinants (dental attendance and plaque level). Media exposure should be observed by community health program planners and general practitioners to examine the type and frequency of the messages. They also need to react on time to balanced bad advertising and add a good message at the community. This pragmatic approach could lead to better use of the media and improve oral health behavior and outcomes.
McDonald, Mark A; Hildebrand, John A; Wiggins, Sean M
2006-08-01
Recent measurement at a previously studied location illustrates the magnitude of increases in ocean ambient noise in the Northeast Pacific over the past four decades. Continuous measurements west of San Nicolas Island, California, over 138 days, spanning 2003-2004 are compared to measurements made during the 1960s at the same site. Ambient noise levels at 30-50 Hz were 10-12 dB higher (95% CI = 2.6 dB) in 2003-2004 than in 1964-1966, suggesting an average noise increase rate of 2.5-3 dB per decade. Above 50 Hz the noise level differences between recording periods gradually diminished to only 1-3 dB at 100-300 Hz. Above 300 Hz the 1964-1966 ambient noise levels were higher than in 2003-2004, owing to a diel component which was absent in the more recent data. Low frequency (10-50 Hz) ocean ambient noise levels are closely related to shipping vessel traffic. The number of commercial vessels plying the world's oceans approximately doubled between 1965 and 2003 and the gross tonnage quadrupled, with a corresponding increase in horsepower. Increases in commercial shipping are believed to account for the observed low-frequency ambient noise increase.
Avci, Ilknur Aydin
2008-04-01
The purpose of this descriptive correlational study was to identify knowledge levels and performance frequency of breast self-examination (BSE) and to examine variables related to breast cancer screening behaviors in a sample of Turkish women. Data were collected from a convenience sample of 103 Muslim female workers at a hazelnut factory in Ordu city, Turkey, using an adapted version of Champion's revised Health Belief Model Scale. Results showed that 26.2% of the women reported knowledge of BSE and 4.3% reported that they perform BSE. Higher health motivation, higher perceived self-efficacy of BSE, marital status, and familial breast cancer history were significantly associated with BSE performance. Higher levels of health motivation and higher perceived self-efficacy of BSE were also significantly associated with knowledge of BSE.
Monson, Brian B.; Lotto, Andrew J.; Story, Brad H.
2012-01-01
The human singing and speech spectrum includes energy above 5 kHz. To begin an in-depth exploration of this high-frequency energy (HFE), a database of anechoic high-fidelity recordings of singers and talkers was created and analyzed. Third-octave band analysis from the long-term average spectra showed that production level (soft vs normal vs loud), production mode (singing vs speech), and phoneme (for voiceless fricatives) all significantly affected HFE characteristics. Specifically, increased production level caused an increase in absolute HFE level, but a decrease in relative HFE level. Singing exhibited higher levels of HFE than speech in the soft and normal conditions, but not in the loud condition. Third-octave band levels distinguished phoneme class of voiceless fricatives. Female HFE levels were significantly greater than male levels only above 11 kHz. This information is pertinent to various areas of acoustics, including vocal tract modeling, voice synthesis, augmentative hearing technology (hearing aids and cochlear implants), and training/therapy for singing and speech. PMID:22978902
Estimating cognitive workload using wavelet entropy-based features during an arithmetic task.
Zarjam, Pega; Epps, Julien; Chen, Fang; Lovell, Nigel H
2013-12-01
Electroencephalography (EEG) has shown promise as an indicator of cognitive workload; however, precise workload estimation is an ongoing research challenge. In this investigation, seven levels of workload were induced using an arithmetic task, and the entropy of wavelet coefficients extracted from EEG signals is shown to distinguish all seven levels. For a subject-independent multi-channel classification scheme, the entropy features achieved high accuracy, up to 98% for channels from the frontal lobes, in the delta frequency band. This suggests that a smaller number of EEG channels in only one frequency band can be deployed for an effective EEG-based workload classification system. Together with analysis based on phase locking between channels, these results consistently suggest increased synchronization of neural responses for higher load levels. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Gray, R. B.; Pierce, G. A.
1972-01-01
Wind tunnel tests were performed on two oscillating two-dimensional lifting surfaces. The first of these models had an NACA 0012 airfoil section while the second simulated the classical flat plate. Both of these models had a mean angle of attack of 12 degrees while being oscillated in pitch about their midchord with a double amplitude of 6 degrees. Wake surveys of sound pressure level were made over a frequency range from 16 to 32 Hz and at various free stream velocities up to 100 ft/sec. The sound pressure level spectrum indicated significant peaks in sound intensity at the oscillation frequency and its first harmonic near the wake of both models. From a comparison of these data with that of a sound level meter, it is concluded that most of the sound intensity is contained within these peaks and no appreciable peaks occur at higher harmonics. It is concluded that within the wake the sound intensity is largely pseudosound while at one chord length outside the wake, it is largely true vortex sound. For both the airfoil and flat plate the peaks appear to be more strongly dependent upon the airspeed than on the oscillation frequency. Therefore reduced frequency does not appear to be a significant parameter in the generation of wake sound intensity.
Measurement and analysis of radiofrequency radiations from some mobile phone base stations in Ghana.
Amoako, J K; Fletcher, J J; Darko, E O
2009-08-01
A survey of the radiofrequency electromagnetic radiation at public access points in the vicinity of 50 cellular phone base stations has been carried out. The primary objective was to measure and analyse the electromagnetic field strength levels emitted by antennae installed and operated by the Ghana Telecommunications Company. On all the sites measurements were made using a hand-held spectrum analyser to determine the electric field level with the 900 and 1800 MHz frequency bands. The results indicated that power densities at public access points varied from as low as 0.01 microW m(-2) to as high as 10 microW m(-2) for the frequency of 900 MHz. At a transmission frequency of 1800 MHz, the variation of power densities is from 0.01 to 100 microW m(-2). The results were found to be in compliant with the International Commission on Non-ionizing Radiological Protection guidance level but were 20 times higher than the results generally obtained for such a practice elsewhere. There is therefore a need to re-assess the situation to ensure reduction in the present level as an increase in mobile phone usage is envisaged within the next few years.
Single-transducer dual-frequency ultrasound generation to enhance acoustic cavitation.
Liu, Hao-Li; Hsieh, Chao-Ming
2009-03-01
Dual- or multiple-frequency ultrasound stimulation is capable of effectively enhancing the acoustic cavitation effect over single-frequency ultrasound. Potential application of this sonoreactor design has been widely proposed such as on sonoluminescence, sonochemistry enhancement, and transdermal drug release enhancement. All currently available sonoreactor designs employed multiple piezoelectric transducers for generating single-frequency ultrasonic waves separately and then these waves were mixed and interfered in solutions. The purpose of this research is to propose a novel design of generating dual-frequency ultrasonic waves with single piezoelectric elements, thereby enhancing acoustic cavitation. Macroscopic bubbles were detected optically, and they were quantified at either a single-frequency or for different frequency combinations for determining their efficiency for enhancing acoustic cavitation. Visible bubbles were optically detected and hydrogen peroxide was measured to quantify acoustic cavitation. Test water samples with different gas concentrations and different power levels were used to determine the efficacy of enhancing acoustic cavitation of this design. The spectrum obtained from the backscattered signals was also recorded and examined to confirm the occurrence of stable cavitation. The results confirmed that single-element dual-frequency ultrasound stimulation can enhance acoustic cavitation. Under certain testing conditions, the generation of bubbles can be enhanced up to a level of five times higher than the generation of bubbles in single-frequency stimulation, and can increase the hydrogen peroxide production up to an increase of one fold. This design may serve as a useful alternative for future sonoreactor design owing to its simplicity to produce dual- or multiple-frequency ultrasound.
Therapist adherence is associated with outcome in cognitive-behavioral therapy for bulimia nervosa.
Folke, Sofie; Daniel, Sarah I F; Gondan, Matthias; Lunn, Susanne; Tækker, Louise; Poulsen, Stig
2017-06-01
Studies of therapist adherence in relation to treatment outcome have produced mixed results. The aim of the present study was to investigate change in therapist adherence to cognitive-behavioral therapy (CBT) for bulimia nervosa over time, and to investigate the relationship between adherence and client outcome in early, middle, and late phases of treatment. Thirty-six clients received the focused form of "enhanced" CBT (CBT-E) for bulimia nervosa. Trained observers rated audiotapes of 92 full-length therapy sessions from early (Session 3), middle (Session 11), and late phases (Session 20) of treatment using the Cognitive-Behavioral Therapy Treatment Protocol Adherence Scale. Change in adherence across the 3 treatment phases was examined using multilevel analysis. The relationship between early, middle, and late adherence levels and end-of-treatment binging frequency was examined using multilevel Poisson regression analysis. Adherence decreased significantly over the course of treatment. Higher levels of therapist adherence in early and middle phases of treatment were associated with reduced binging frequency, whereas higher levels of adherence measured late in treatment was not. Results indicate that therapists' adherence to the CBT-E treatment protocol decreases over time and that high levels of protocol adherence in early and middle phases of treatment are more important for positive client outcomes than high levels of adherence in the end of treatment. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Dopamine receptor D4 promoter hypermethylation increases the risk of drug addiction.
Ji, Huihui; Xu, Xuting; Liu, Guili; Liu, Huifen; Wang, Qinwen; Shen, Wenwen; Li, Longhui; Xie, Xiaohu; Hu, Haochang; Xu, Lei; Zhou, Wenhua; Duan, Shiwei
2018-02-01
Heroin and methylamphetamine (METH) are two addictive drugs that cause serious problems for society. Dopamine receptor D4 (DRD4), a key receptor in the dopaminergic system, may facilitate the development of drug addiction. The aim of the present study was to investigate the association between the promoter methylation level of DRD4 gene and drug addiction. Bisulfite pyrosequencing technology was used to measure the methylation levels of DRD4 promoter in 60 drug addicts and 52 matched controls. Significantly higher levels of DRD4 CpG1 and CpG4 methylation were detected in METH and heroin drug addicts compared with controls (P<0.05). Male METH addicts exhibited significantly higher DRD4 CpG1, CpG2 and CpG4 methylation levels compared with sex-matched controls (P<0.05). In heroin addicts, a positive correlation was observed between depression-dejection and DRD4 CpG5 methylation (r=0.537, P=0.039) whereas there was a negative correlation between drug usage frequency and CpG1 methylation (r=-0.632, P=0.011). In METH addicts, methylation levels were not significantly associated with depression-dejection and drug usage frequency. In addition, luciferase assays demonstrated that the target sequence of the DRD4 promoter upregulates gene expression. The results of the present study suggest that DNA methylation of DRD4 may be responsible for the pathophysiology of drug addiction.
Taweesak, Viyachai; Lee Abdullah, Thohirah; Hassan, Siti Aishah; Kamarulzaman, Nitty Hirawaty; Wan Yusoff, Wan Abdullah
2014-01-01
Influences of irrigation frequency on the growth and flowering of chrysanthemum grown under restricted root volume were tested. Chrysanthemum cuttings (Chrysanthemum morifolium “Reagan White”) were grown in seedling tray which contained coconut peat in volumes of 73 and 140 cm3. Plants were irrigated with drip irrigation at irrigation frequencies of 4 (266 mL), 6 (400 mL), and 8 (533 mL) times/day to observe their growth and flowering performances. There was interaction between irrigation frequency and substrate volume on plant height of chrysanthemum. Plants grown in 140 cm3 substrates and irrigated 6 times/day produced the tallest plant of 109.25 cm. Plants irrigated 6 and 8 times/day had significantly higher level of phosphorus content in their leaves than those plants irrigated 4 times/day. The total leaf area, number of internodes, leaf length, and leaf width of chrysanthemums grown in 140 cm3 substrate were significantly higher than those grown in 73 cm3 substrate. The numbers of flowers were affected by both irrigation frequencies and substrate volumes. Chrysanthemums irrigated 8 times/day had an average of 19.56 flowers while those irrigated 4 times/day had an average of 16.63 flowers. Increasing irrigation frequency can improve the growth and flowering of chrysanthemums in small substrate volumes. PMID:25478586
Özer Yücel, Özlem; Berker, Ezel; Mesci, Lütfiye; Eratalay, Kenan; Tepe, Eser; Tezcan, İlhan
2015-04-01
The purpose of this study was to determine the differences in the distribution of TNF-α (-308) gene polymorphism among aggressive periodontitis, chronic periodontitis and periodontally healthy individuals and also to investigate whether this polymorphism is associated with gingival crevicular fluid TNF-α levels and periodontal disease severity. A total of 93 individuals were enrolled in the study including 38 aggressive periodontitis, 29 chronic periodontitis patients, and 26 healthy controls. Single nucleotide polymorphism at TNF-α (-308) is analyzed by PCR-RFLP method. Gingival crevicular fluid samples were analyzed for TNF-α, using ELISA. The distribution of genotypes and allele frequencies for TNF-α (-308) were similar among the groups. After stratification of patients with respect to attachment level, aggressive periodontitis patients with clinical attachment level ⩾4mm was observed to have a higher frequency of TNF-α (-308) allele 2 compared to the chronic periodontitis patients with clinical attachment level ⩾4mm. No significant differences were found between the TNF-α levels of the different genotypes in spite of an insignificant increase in patient groups carrying TNF-α (-308) allele 2. The results of this study revealed an association between TNF-α (-308) allele 2 frequency and aggressive periodontitis patients with clinical attachment level ⩾4mm in the population studied. Copyright © 2015 Elsevier Ltd. All rights reserved.
[Unusually high level of chromosome variability in cultured human peripheral blood lymphocytes].
Bochkov, N P; Popova, N A; Katosova, L D; Iakovleva, Iu S; Nazarenko, S A; Vasil'eva, E O; Platonova, V I; Chebotarev, A N
1999-06-01
A cytogenetic examination carried out in the inhabitants of Seversk (Tomsk oblast) and workers of the Siberian chemical industrial complex (a complex of nuclear-chemical and fuel plants), living in the same town, revealed unusually high level of spontaneous chromosomal variability both in control and industrial groups (total irradiation doses 1.8 to 3.7 and 9.3 to 15.7 Gy, respectively). The frequencies of cells with chromosomal aberrations (estimated per 100 cells) in control and industrial groups were 4.69, 6.04, and 6.64, respectively, and the total number of aberrations constituted 6.93, 8.47 and 12.06, respectively. These frequencies were several times higher compared to the summarized literature data on the control levels. The high average aberration level was caused by the elevated proportion of chromatid-type aberrations and paired fragments. The reasons for this are unclear. The levels of radioactive background and chemical air pollution in the town were not increased.
An evaluation of Space Shuttle STS-2 payload bay acoustic data and comparison with predictions
NASA Technical Reports Server (NTRS)
Wilby, J. F.; Piersol, A. G.; Wilby, E. G.
1982-01-01
Space average sound pressure levels computed from measurements at 18 locations in the payload bay of the Space Shuttle orbiter vehicle during the STS-2 launch were compared with predicted levels obtained using the PACES computer program. The comparisons were performed over the frequency range 12.5 Hz to 1000 Hz, since the test data at higher frequencies are contaminated by instrumentation background noise. In general the PACES computer program tends to overpredict the space average sound levels in the payload bay, although the magnitude of the discrepancy is usually small. Furthermore the discrepancy depends to some extent on the manner in which the payload is modeled analytically, and the method used to determine the "measured' space average sound pressure levels. Thus the difference between predicted and measured sound levels, averaged over the 20 one third octave bands from 12.5 Hz to 1000 Hz, varies from 1 dB to 3.5 dB.
Effects of ocular aberrations on contrast detection in noise.
Liang, Bo; Liu, Rong; Dai, Yun; Zhou, Jiawei; Zhou, Yifeng; Zhang, Yudong
2012-08-06
We use adaptive optics (AO) techniques to manipulate the ocular aberrations and elucidate the effects of these ocular aberrations on contrast detection in a noisy background. The detectability of sine wave gratings at frequencies of 4, 8, and 16 circles per degree (cpd) was measured in a standard two-interval force-choice staircase procedure against backgrounds of various levels of white noise. The observer's ocular aberrations were either corrected with AO or left uncorrected. In low levels of external noise, contrast detection thresholds are always lowered by AO correction, whereas in high levels of external noise, they are generally elevated by AO correction. Higher levels of external noise are required to make this threshold elevation observable when signal spatial frequencies increase from 4 to 16 cpd. The linear-amplifier-model fit shows that mostly sampling efficiency and equivalent noise both decrease with AO correction. Our findings indicate that ocular aberrations could be beneficial for contrast detection in high-level noises. The implications of these findings are discussed.
Blades, Brittany; Parks, Susan E.
2018-01-01
During the breeding season, male harbor seals (Phoca vitulina) make underwater acoustic displays using vocalizations known as roars. These roars have been shown to function in territory establishment in some breeding areas and have been hypothesized to be important for female choice, but the function of these sounds remains unresolved. This study consisted of a series of playback experiments in which captive female harbor seals were exposed to recordings of male roars to determine if females respond to recordings of male vocalizations and whether or not they respond differently to roars from categories with different acoustic characteristics. The categories included roars with characteristics of dominant males (longest duration, lowest frequency), subordinate males (shortest duration, highest frequency), combinations of call parameters from dominant and subordinate males (long duration, high frequency and short duration, low frequency), and control playbacks of water noise and water noise with tonal signals in the same frequency range as male signals. Results indicate that overall females have a significantly higher level of response to playbacks that imitate male vocalizations when compared to control playbacks of water noise. Specifically, there was a higher level of response to playbacks representing dominant male vocalization when compared to the control playbacks. For most individuals, there was a greater response to playbacks representing dominant male vocalizations compared to playbacks representing subordinate male vocalizations; however, there was no statistical difference between those two playback types. Additionally, there was no difference between the playbacks of call parameter combinations and the controls. Investigating female preference for male harbor seal vocalizations is a critical step in understanding the harbor seal mating system and further studies expanding on this captive study will help shed light on this important issue. PMID:29607261
Matthews, Leanna P; Blades, Brittany; Parks, Susan E
2018-01-01
During the breeding season, male harbor seals ( Phoca vitulina ) make underwater acoustic displays using vocalizations known as roars. These roars have been shown to function in territory establishment in some breeding areas and have been hypothesized to be important for female choice, but the function of these sounds remains unresolved. This study consisted of a series of playback experiments in which captive female harbor seals were exposed to recordings of male roars to determine if females respond to recordings of male vocalizations and whether or not they respond differently to roars from categories with different acoustic characteristics. The categories included roars with characteristics of dominant males (longest duration, lowest frequency), subordinate males (shortest duration, highest frequency), combinations of call parameters from dominant and subordinate males (long duration, high frequency and short duration, low frequency), and control playbacks of water noise and water noise with tonal signals in the same frequency range as male signals. Results indicate that overall females have a significantly higher level of response to playbacks that imitate male vocalizations when compared to control playbacks of water noise. Specifically, there was a higher level of response to playbacks representing dominant male vocalization when compared to the control playbacks. For most individuals, there was a greater response to playbacks representing dominant male vocalizations compared to playbacks representing subordinate male vocalizations; however, there was no statistical difference between those two playback types. Additionally, there was no difference between the playbacks of call parameter combinations and the controls. Investigating female preference for male harbor seal vocalizations is a critical step in understanding the harbor seal mating system and further studies expanding on this captive study will help shed light on this important issue.
Bhaumik, G; Dass, D; Bhattacharyya, D; Sharma, Y K; Singh, S B
2013-01-01
Acute exposure to hypobaric hypoxia induces the changes in autonomic control of heart rate. Due to emergencies or war like conditions, rapid deployment of Indian military personnel into high altitude frequently occurs. Rapid deployment to high altitude soldiers are at risk of developing high altitude sickness. The present study was conducted to evaluate the acute exposure to high altitude hypobaric hypoxia (3500 m altitude) on the autonomic nervous control of heart rate in Indian military personnel during first week of acclimatization Indices of heart rate variability (viz; R-R interval, total power, low frequency, high frequency, ratio of low to high frequency) and pulse arterial oxygen saturation were measured at sea level and 3500m altitude. Power spectrum of heart rate variability was quantified by low frequency (LF: 0.04-0.15 Hz) and high frequency (HF: 0.15-0.5 Hz) widths. The ratio of LF to HF was also assessed as an index of the sympathovagal balance. Mean R-R interval decreased significantly on day 2 on induction to altitude which tended to increase on day 5. Total power (TP) decreased high altitude and tended to recover within a week. Both HF and LF power showed decrement at 3500m in comparison to sea level. The ratio of LF to HF (LF/HF) at 3500m was significantly higher at 3500m. SpO2 values decreased significantly (P < 0.05) at high altitude on day-2 which increased on day-5. We conclude that autonomic control of the heart rate measured by heart rate variability was altered on acute induction to 3500m which showed a significant decrease in parasympathetic tone and increase in sympathetic tone, then acclimatization seems to be characterized by progressive shift toward a higher parasympathetic tone.
Forms of Spanking and Children's Externalizing Behaviors
ERIC Educational Resources Information Center
Lansford, Jennifer E.; Wager, Laura B.; Bates, John E.; Pettit, Gregory S.; Dodge, Kenneth A.
2012-01-01
Research suggests that corporal punishment is related to higher levels of child externalizing behavior, but there has been controversy regarding whether infrequent, mild spanking predicts child externalizing or whether more severe and frequent forms of corporal punishment account for the link. Mothers rated the frequency with which they spanked…
On the Word Preferences of Suicidal versus Nonsuicidal College Students.
ERIC Educational Resources Information Center
Thurber, Steven; Torbet, David P.
1978-01-01
A word preference format was used to investigate reactions to verbal stimuli of suicidal and nonsuicidal persons. Words with aggressive or submissive denotative meanings significantly differentiated the two groups. The word "suicide" was selected at a higher frequency level by suicidal individuals when compared to their nonsuicidal counterparts.…
Activity Participation and Well-Being among Older People with Arthritis.
ERIC Educational Resources Information Center
Zimmer, Zachary; And Others
1995-01-01
Tested hypotheses that severity of arthritis is inversely associated with frequency of activity participation, and arthritis sufferers who maintain higher levels of participation, particularly in social activities, are less likely to experience a decline in well-being. Found well-being is influenced by social activity, whereas solitary and…
Direction of an initial saccade depends on radiological expertise
NASA Astrophysics Data System (ADS)
Pietrzyk, Mariusz W.; McEntee, Mark F.; Evanoff, Michael E.; Brennan, Patrick C.; Mello-Thoms, Claudia R.
2014-03-01
Purpose: To evaluate the role of radiographic details in global impression of chest x-ray images viewed by experts in thoracic and non-thoracic domains. Materials and Methods: The study was approved by IRB. Five thoracic and five non-thoracic radiologists participated in two tachistoscopic (one low pass and one with the entire frequency spectrum, each lasting 270 ms) each containing 50 PA chest radiographs with 50% prevalence of pulmonary nodule. Eye movements were monitored in order to evaluate a pre-saccade shift of visual attention, saccade latency, decision time and the time to first fixation on a pulmonary nodule. Results: Thoracic radiologists showed significantly higher pre-saccadic shift of visual attention towards pulmonary nodules once using the full frequency spectrum (p < 0.05). An initial saccade orientation made by these radiologists on full resolution images correlated at significant level with their confidence ranking of pulmonary nodules (ρ = -0.387, p < 0.001). Conclusions: Thoracic radiologists benefited from high spatial frequency appearance during a rapid presentation of chest radiograph by allocating pre-saccade attention towards pulmonary nodules. This behavior correlated with a higher number of correct decisions, followed by higher confidence in the decisions made, and briefer reaction times.
NASA Astrophysics Data System (ADS)
Cheriton, O. M.; Storlazzi, C. D.; Rosenberger, K. J.
2016-02-01
Low-lying, reef-fringed islands are susceptible to sea-level rise and often subjected to overwash and flooding during large wave events. To quantify wave dynamics and wave-driven water levels on fringing coral reefs, wave gauges and a current meter were deployed for 5 months across two shore-normal transects on Roi-Namur, an atoll island in the Republic of the Marshall Islands. These observations captured two large wave events that had maximum wave heights greater than 6 m and peak periods of 16 s over the fore reef. The larger event coincided with a peak spring tide, leading to energetic, highly-skewed infragravity (0.04-0.004 Hz) and very low frequency (0.004-0.001 Hz) waves at the shoreline, which reached heights of 1.0 and 0.7 m, respectively. Water surface elevations, combined with wave runup, exceeded 3.7 m at the innermost reef flat adjacent to the toe of the beach, resulting in flooding of inland areas. This overwash occurred during a 3-hr time window that coincided with high tide and maximum low-frequency reef flat wave heights. The relatively low-relief characteristics of this narrow reef flat may further drive shoreline amplification of low-frequency waves due to resonance modes. These results demonstrate how the coupling of high offshore water levels with low-frequency reef flat wave energetics can lead to large impacts along atoll and fringing reef-lined shorelines, such as island overwash. These observations lend support to the hypothesis that predicted higher sea levels will lead to more frequent occurrences of both extreme shoreline runup and island overwash, threatening the sustainability of these islands.
NASA Astrophysics Data System (ADS)
Cheriton, Olivia M.; Storlazzi, Curt D.; Rosenberger, Kurt J.
2016-05-01
Many low-lying tropical islands are susceptible to sea level rise and often subjected to overwash and flooding during large wave events. To quantify wave dynamics and wave-driven water levels on fringing coral reefs, a 5 month deployment of wave gauges and a current meter was conducted across two shore-normal transects on Roi-Namur Island in the Republic of the Marshall Islands. These observations captured two large wave events that had waves with maximum heights greater than 6 m with peak periods of 16 s over the fore reef. The larger event coincided with a peak spring tide, leading to energetic, highly skewed infragravity (0.04-0.004 Hz) and very low frequency (0.004-0.001 Hz) waves at the shoreline, which reached heights of 1.0 and 0.7 m, respectively. Water surface elevations, combined with wave runup, reached 3.7 m above the reef bed at the innermost reef flat adjacent to the toe of the beach, resulting in flooding of inland areas. This overwash occurred during a 3 h time window that coincided with high tide and maximum low-frequency reef flat wave heights. The relatively low-relief characteristics of this narrow reef flat may further drive shoreline amplification of low-frequency waves due to resonance modes. These results (1) demonstrate how the coupling of high offshore water levels with low-frequency reef flat wave energetics can lead to large impacts along fringing reef-lined shorelines, such as island overwash, and (2) lend support to the hypothesis that predicted higher sea levels will lead to more frequent occurrences of these extreme events, negatively impacting coastal resources and infrastructure.
Cheriton, Olivia; Storlazzi, Curt; Rosenberger, Kurt
2016-01-01
Many low-lying tropical islands are susceptible to sea level rise and often subjected to overwash and flooding during large wave events. To quantify wave dynamics and wave-driven water levels on fringing coral reefs, a 5 month deployment of wave gauges and a current meter was conducted across two shore-normal transects on Roi-Namur Island in the Republic of the Marshall Islands. These observations captured two large wave events that had waves with maximum heights greater than 6 m with peak periods of 16 s over the fore reef. The larger event coincided with a peak spring tide, leading to energetic, highly skewed infragravity (0.04–0.004 Hz) and very low frequency (0.004–0.001 Hz) waves at the shoreline, which reached heights of 1.0 and 0.7 m, respectively. Water surface elevations, combined with wave runup, reached 3.7 m above the reef bed at the innermost reef flat adjacent to the toe of the beach, resulting in flooding of inland areas. This overwash occurred during a 3 h time window that coincided with high tide and maximum low-frequency reef flat wave heights. The relatively low-relief characteristics of this narrow reef flat may further drive shoreline amplification of low-frequency waves due to resonance modes. These results (1) demonstrate how the coupling of high offshore water levels with low-frequency reef flat wave energetics can lead to large impacts along fringing reef-lined shorelines, such as island overwash, and (2) lend support to the hypothesis that predicted higher sea levels will lead to more frequent occurrences of these extreme events, negatively impacting coastal resources and infrastructure.
Fong, Cristian; Menzel, Stephan; Lizarralde, María Alejandra; Barreto, Guillermo
2015-01-01
Fetal hemoglobin is an important factor in modulating the severity of sickle cell anemia. Its level in peripheral blood underlies strong genetic determination. Associated loci with increased levels of fetal hemoglobin display population-specific allele frequencies. We investigated the presence and effect of known common genetic variants promoting fetal hemoglobin persistence (rs11886868, rs9399137, rs4895441, and rs7482144) in 60 Colombian patients with sickle cell anemia. Four single nucleotide polymorphisms (SNP) were genotyped by restriction fragment length polymorphisms (RFLP) and the use of the TaqMan procedure. Fetal hemoglobin (HbF) from these patients was quantified using the oxyhemoglobin alkaline denaturation technique. Genotype frequencies were compared with frequencies reported in global reference populations. We detected genetic variants in the four SNPs, reported to be associated with higher HbF levels for all four SNPs in the Colombian patients. Genetic association between SNPs and HbF levels did not reach statistical significance. The frequency of these variants reflected the specific ethnic make-up of our patient population: A high prevalence of rs7482144-'A' reflects the West-African origin of the sickle cell mutation, while high frequencies of rs4895441-'G' and rs11886868-'C' point to a significant influence of an Amerindian ethnic background in the Colombian sickle cell disease population. These results showed that in the sickle cell disease population in Colombia there is not a unique genetic background, but two (African and Amerindian). This unique genetic situation will provide opportunities for a further study of these loci, such as fine-mapping and molecular-biological investigation. Colombian patients are expected to yield a distinctive insight into the effect of modifier loci in sickle cell disease.
Coherent storage of temporally multimode light using a spin-wave atomic frequency comb memory
NASA Astrophysics Data System (ADS)
Gündoǧan, M.; Mazzera, M.; Ledingham, P. M.; Cristiani, M.; de Riedmatten, H.
2013-04-01
We report on the coherent and multi-temporal mode storage of light using the full atomic frequency comb memory scheme. The scheme involves the transfer of optical atomic excitations in Pr3+:Y2SiO5 to spin waves in hyperfine levels using strong single-frequency transfer pulses. Using this scheme, a total of five temporal modes are stored and recalled on-demand from the memory. The coherence of the storage and retrieval is characterized using a time-bin interference measurement resulting in visibilities higher than 80%, independent of the storage time. This coherent and multimode spin-wave memory is promising as a quantum memory for light.
An Ongoing Shift in Pacific Ocean Sea Level
NASA Astrophysics Data System (ADS)
Cheon, S. H.; Hamlington, B.; Thompson, P. R.; Merrifield, M. A.; Nerem, R. S.; Leben, R. R.; Kim, K. Y.
2016-12-01
According to the satellite altimeter data, local sea level trends have shown considerable diversity spatially as well as temporally. In particular, dramatic changes in sea level in the Pacific have been observed throughout the altimeter record, with high trends in the western tropical Pacific (WTP) and comparatively lower trends in the eastern Pacific. In recent years, however, a shift appears to be occurring, with falling trends in the (WTP) and rising trends in the eastern tropical and northeastern Pacific (ETP and NEP). From a planning perspective, it is important to figure out whether these sharp changes are part of a short-term shift or the beginning of a longer-term change in sea level. In this study, we distinguish the origins of the recent shift in Pacific Ocean sea level. Cyclostationary empirical orthogonal function (CSEOF) analysis is applied to separate the properties of the recent sea level change in the Pacific Ocean. From the CSEOF analysis results, we point out two dominant modes of sea level shift in the Pacific Ocean. The first mode is related to the biennial oscillation associated with El Nino-Southern Oscillation (ENSO) and the other is related to lower-frequency variability with a strong signal in the northern Pacific. Considering a relatively high correlation between recent sea level change and the low-frequency mode, we suggest that the low-frequency mode has played a dominant role in the sea level shift in the Pacific Ocean. Using a reconstructed sea level dataset, we examine the variability of this low-frequency mode in the past, and find similar periods of dramatic sea level change in the Pacific. Based on the sea level record of the last five years and according to the analysis, we conclude that in the coming decades, higher sea level trends off the U.S. West Coast should be expected, while reduced trends in the WTP will likely be observed.
Fuglevand, A J; Macefield, V G; Bigland-Ritchie, B
1999-04-01
Modulation of motor unit activation rate is a fundamental process by which the mammalian nervous system encodes muscle force. To identify how rate coding of force may change as a consequence of fatigue, intraneural microstimulation of motor axons was used to elicit twitch and force-frequency responses before and after 2 min of intermittent stimulation (40-Hz train for 330 ms, 1 train/s) in single motor units of human long finger flexor muscles and intrinsic hand muscles. Before fatigue, two groups of units could be distinguished based on the stimulus frequency needed to elicit half-maximal force; group 1 (n = 8) required 9.1 +/- 0.5 Hz (means +/- SD), and group 2 (n = 5) required 15.5 +/- 1.1 Hz. Twitch contraction times were significantly different between these two groups (group 1 = 66. 5 ms; group 2 = 45.9 ms). Overall 18% of the units were fatigue resistant [fatigue index (FI) > 0.75], 64% had intermediate fatigue sensitivity (0.25 = FI = 0.75), and 18% were fatigable (FI < 0. 25). However, fatigability and tetanic force were not significantly different among groups. Therefore unlike findings in some other mammals, fast-contracting motor units were neither stronger nor more susceptible to fatigue than slowly contracting units. Fatigue, however, was found to be greatest in those units that initially exerted the largest forces. Despite significant slowing of contractile responses, fatigue caused the force-frequency relation to become displaced toward higher frequencies (44 +/- 41% increase in frequency for half-maximal force). Moreover, the greatest shift in the force-frequency relation occurred among those units exhibiting the largest force loss. A selective deficit in force at low frequencies of stimulation persisted for several minutes after the fatigue task. Overall, these findings suggest that with fatigue higher activation rates must be delivered to motor units to maintain the same relative level of force. Questions regarding classification of motor units and possible mechanisms by which fatigue-related slowing might coexist with a shift in the force-frequency curve toward higher frequencies are discussed.
[Ionization energies and infrared spectra studies of histidine using density functional theory].
Hu, Qiong; Wang, Guo-Ying; Liu, Gang; Ou, Jia-Ming; Wang, Rui-Li
2010-05-01
Histidines provide axial ligands to the primary electron donors in photosynthetic reaction centers (RCs) and play an important role in the protein environments of these donors. In this paper the authors present a systematic study of ionization energies and vibrational properties of histidine using hybrid density functional theory (DFT). All calculations were undertaken by using B3LYP method in combination with four basis sets: 6-31G(d), 6-31G(df, p), 6-31+G(d) and 6-311+G(2d, 2p) with the aim to investigate how the basis sets influence the calculation results. To investigate solvent effects and gain a detailed understanding of marker bands of histidine, the ionization energies of histidine and the vibrational frequencies of histidine which are unlabeled and 13C, 15N, and 2H labeled in the gas phase, CCl4, protein environment, THF and water solution, which span a wide range of dielectric constant, were also calculated. Our results showed that: (1) The main geometry parameters of histidine were impacted by basis sets and mediums, and C2-N3 and N3-C4 bond of imidazole ring of histidine side chain display the maximum bond lengths in the gas phase; (2) single point energies and frequencies calculated were decreased while ionization energies increased with the increasing level of basis sets and diffuse function applied in the same solvent; (3) with the same computational method, the higher the dielectric constant of the solvent used, the lower the ionization energy and vibrational frequency and the higher the intensity obtained. In addition, calculated ionization energy in the gas phase and marker bands of histidine as well as frequency shift upon 13C and 15N labeling at the computationally more expensive 6-311+G(2d, 2p) level are in good agreement with experimental observations available in literatures. All calculations indicated that the results calculated by using higher level basis set with diffuse function were more accurate and closer to the experimental value. In conclusion, the results provide useful information for the further studies of the functional and vibrational properties of chlorophyll-a ligated to histidine residue in photosynthetic reaction center.
Responding to Nonwords in the Lexical Decision Task: Insights from the English Lexicon Project
Yap, Melvin J.; Sibley, Daragh E.; Balota, David A.; Ratcliff, Roger; Rueckl, Jay
2014-01-01
Researchers have extensively documented how various statistical properties of words (e.g., word-frequency) influence lexical processing. However, the impact of lexical variables on nonword decision-making performance is less clear. This gap is surprising, since a better specification of the mechanisms driving nonword responses may provide valuable insights into early lexical processes. In the present study, item-level and participant-level analyses were conducted on the trial-level lexical decision data for almost 37,000 nonwords in the English Lexicon Project in order to identify the influence of different psycholinguistic variables on nonword lexical decision performance, and to explore individual differences in how participants respond to nonwords. Item-level regression analyses reveal that nonword response time was positively correlated with number of letters, number of orthographic neighbors, number of affixes, and baseword number of syllables, and negatively correlated with Levenshtein orthographic distance and baseword frequency. Participant-level analyses also point to within- and between-session stability in nonword responses across distinct sets of items, and intriguingly reveal that higher vocabulary knowledge is associated with less sensitivity to some dimensions (e.g., number of letters) but more sensitivity to others (e.g., baseword frequency). The present findings provide well-specified and interesting new constraints for informing models of word recognition and lexical decision. PMID:25329078
Visual stimulus eccentricity affects human gamma peak frequency.
van Pelt, Stan; Fries, Pascal
2013-09-01
The peak frequency of neuronal gamma-band synchronization has received much attention in recent years. Gamma peak frequency shifts to higher frequency values for higher contrast, faster moving, and attended stimuli. In monkey V1, gamma peak frequency for a drifting grating is higher for a parafoveal as compared to an eccentric stimulus (Lima et al., 2010). This effect might be due to the cortical magnification factor: the higher cortical magnification for parafoveal stimuli increases the velocity with which the cortical representations of the moving grating stripes move across the cortical surface. Since faster moving stimuli lead to higher gamma frequency, a faster moving cortical representation might do the same. This explanation predicts that the eccentricity effect on gamma peak frequency is absent for stationary stimuli. To test this, we investigated the effect of eccentricity on gamma peak frequency by recording magnetoencephalography in human subjects while they viewed moving or stationary gratings. We found that both the moving and the stationary stimuli induced lower peak frequencies for larger eccentricities, arguing against an explanation based on the cortical magnification factor. We further investigated whether this eccentricity effect was explained by differences in the size or the spatial frequency of the expected cortical activation. Neither of those explained the eccentricity effect. We propose that the different stimulus and top-down factors leading to higher gamma peak frequency all result in higher stimulus salience, that salience is translated into gamma peak frequency, and that gamma peak frequency might subserve the preferential processing of neuronal activity induced by salient stimuli. Copyright © 2013 Elsevier Inc. All rights reserved.
Zou, Chao Chun; Huang, Ke; Liang, Li; Zhao, Zheng Yan
2008-07-01
To investigate the role of ghrelin and polymorphisms of ghrelin/obestatin gene in children with short stature. A total of 117 GH deficient (GHD) and 81 idiopathic short stature (ISS) children were studied. The controls consisted of 125 age and gender-matched healthy children. The Arg51Gln, Leu72Met and Gln90Leu polymorphisms were genotyped using MassArray and total plasma ghrelin was measured by radioimmunoassay. In this study, the frequency of the Arg51Gln polymorphism was very low (0% in controls and 1.0% in patients). The frequency of the Gln90Leu polymorphism was 1.6% in controls and 0.5% in patients, respectively. Higher frequencies of Leu72Met (34.4% in controls and 39.9% in patients) and Met72Met genotypes (4.0% in controls and 2.0% in patients) were found. The differences in the Arg51Gln, Leu72Met or Gln90Leu genotypes and allele frequencies between patients and controls were not significant. Also, there were no significant differences in the Leu72Met genotypes and allele frequencies between GHD and ISS subgroups. There were no significant differences in clinical characteristics and biochemistry markers (including ghrelin levels) among the different genotypes of Leu72Met. However, plasma ghrelin levels in the GHD group were significantly lower than those of controls (P = 0.001). These results suggest that ghrelin may have a role in GH secretion and controlling growth. Lower ghrelin levels, but not ghrelin/obestatin polymorphism, might contribute to GHD.
Kent, Stephen; Kashima, Yoshihisa
2015-01-01
Life satisfaction of migrants to Australia from 17 countries, assessed at 4–5 months, 16–17 months and 3½ years after arrival, was analyzed with a longitudinal, multilevel analysis. The results indicated that migrants were more satisfied, if the national average life satisfaction was higher in their country of origin, after adjustment for individual-level income, age, and sex and a linear temporal trend. Simultaneously, the migrants were also happier if people in their country of origin had a higher frequency of 5-HTT long allele, a genotype known to be associated with resilience under life stresses. These two relationships were independent, suggesting that both culture and gene matter in international transitions. PMID:24532702
Experimental Characterization of Secular Frequency Scanning in Ion Trap Mass Spectrometers
NASA Astrophysics Data System (ADS)
Snyder, Dalton T.; Pulliam, Christopher J.; Wiley, Joshua S.; Duncan, Jason; Cooks, R. Graham
2016-07-01
Secular frequency scanning is implemented and characterized using both a benchtop linear ion trap and a miniature rectilinear ion trap mass spectrometer. Separation of tetraalkylammonium ions and those from a mass calibration mixture and from a pesticide mixture is demonstrated with peak widths approaching unit resolution for optimized conditions using the benchtop ion trap. The effects on the spectra of ion trap operating parameters, including waveform amplitude, scan direction, scan rate, and pressure are explored, and peaks at black holes corresponding to nonlinear (higher-order field) resonance points are investigated. Reverse frequency sweeps (increasing mass) on the Mini 12 are shown to result in significantly higher ion ejection efficiency and superior resolution than forward frequency sweeps that decrement mass. This result is accounted for by the asymmetry in ion energy absorption profiles as a function of AC frequency and the shift in ion secular frequency at higher amplitudes in the trap due to higher order fields. We also found that use of higher AC amplitudes in forward frequency sweeps biases ions toward ejection at points of higher order parametric resonance, despite using only dipolar excitation. Higher AC amplitudes also increase peak width and decrease sensitivity in both forward and reverse frequency sweeps. Higher sensitivity and resolution were obtained at higher trap pressures in the secular frequency scan, in contrast to conventional resonance ejection scans, which showed the opposite trend in resolution on the Mini 12. Mass range is shown to be naturally extended in secular frequency scanning when ejecting ions by sweeping the AC waveform through low frequencies, a method which is similar, but arguably superior, to the more usual method of mass range extension using low q resonance ejection.
Experimental Characterization of Secular Frequency Scanning in Ion Trap Mass Spectrometers.
Snyder, Dalton T; Pulliam, Christopher J; Wiley, Joshua S; Duncan, Jason; Cooks, R Graham
2016-07-01
Secular frequency scanning is implemented and characterized using both a benchtop linear ion trap and a miniature rectilinear ion trap mass spectrometer. Separation of tetraalkylammonium ions and those from a mass calibration mixture and from a pesticide mixture is demonstrated with peak widths approaching unit resolution for optimized conditions using the benchtop ion trap. The effects on the spectra of ion trap operating parameters, including waveform amplitude, scan direction, scan rate, and pressure are explored, and peaks at black holes corresponding to nonlinear (higher-order field) resonance points are investigated. Reverse frequency sweeps (increasing mass) on the Mini 12 are shown to result in significantly higher ion ejection efficiency and superior resolution than forward frequency sweeps that decrement mass. This result is accounted for by the asymmetry in ion energy absorption profiles as a function of AC frequency and the shift in ion secular frequency at higher amplitudes in the trap due to higher order fields. We also found that use of higher AC amplitudes in forward frequency sweeps biases ions toward ejection at points of higher order parametric resonance, despite using only dipolar excitation. Higher AC amplitudes also increase peak width and decrease sensitivity in both forward and reverse frequency sweeps. Higher sensitivity and resolution were obtained at higher trap pressures in the secular frequency scan, in contrast to conventional resonance ejection scans, which showed the opposite trend in resolution on the Mini 12. Mass range is shown to be naturally extended in secular frequency scanning when ejecting ions by sweeping the AC waveform through low frequencies, a method which is similar, but arguably superior, to the more usual method of mass range extension using low q resonance ejection. Graphical Abstract ᅟ.
Yatagai, Tsuyoshi; Shimauchi, Takatoshi; Yamaguchi, Hayato; Sakabe, Jun-Ichi; Aoshima, Masahiro; Ikeya, Shigeki; Tatsuno, Kazuki; Fujiyama, Toshiharu; Ito, Taisuke; Ojima, Toshiyuki; Tokura, Yoshiki
2018-01-01
Sensitive skin is a condition of cutaneous hypersensitivity to environmental factors. Lactic acid stinging test (LAST) is commonly used to assess sensitive skin and composed of four distinct sensations (pain, burning sensation, itch, and crawly feeling). A link between sensitive skin and barrier dysfunction has been proposed in atopic dermatitis (AD) patients. However, clinical and laboratory factors that are associated with sensitive skin remain unelucidated. To investigate relationship between sensitive skin and AD-associated markers. Forty-two Japanese AD patients and 10 healthy subjects (HS) were enrolled. AD patients were divided into extrinsic (EAD; high IgE levels) and intrinsic (IAD; normal IgE levels) types. We conducted 1% LAST by assessing the four distinct sensations and calculated the frequencies of sensitive skin in EAD, IAD, and HS. We also performed clinical AD-related tests, including transepidermal water loss (TEWL), visual analogue scale (VAS) of pruritus, and quality of life, and measured laboratory markers, including blood levels of IgE, CCL17/TARC, lactate dehydrogenase (LDH) and eosinophil counts, and concentration levels of serum Th1/Th2 cytokines. Filaggrin (FLG) mutations were examined in 21 patients. These values were subjected to correlation analyses with each of the four sensation elements. According to the standard criteria for LAST positivity, the frequencies of LAST-positive subjects were 54.8% and 10.0% in AD and HS, respectively (P=0.014). EAD patients showed a significantly (P=0.026) higher frequency of positive LAST (65.6%) than did IAD patients (20.0%). Among the four LAST sensation elements, the crawly feeling and pain scores positively correlated with VAS of pruritus, total serum IgE, mite-specific IgE, CCL17/TARC, and/or LDH. There was no association of the LAST scores with serum Th1/Th2 cytokine levels. Notably, neither TEWL nor FLG mutations correlated with LAST positivity or any sensation scores. The frequency of sensitive skin is higher in EAD than in IAD. Sensitive skin is associated with AD severity, but not necessarily with barrier condition. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.
Memory bias in health anxiety is related to the emotional valence of health-related words.
Ferguson, Eamonn; Moghaddam, Nima G; Bibby, Peter A
2007-03-01
A model based on the associative strength of object evaluations is tested to explain why those who score higher on health anxiety have a better memory for health-related words. Sixty participants observed health and nonhealth words. A recognition memory task followed a free recall task and finally subjects provided evaluations (emotionality, imageability, and frequency) for all the words. Hit rates for health words, d', c, and psychological response times (PRTs) for evaluations were examined using multi-level modelling (MLM) and regression. Health words had a higher hit rate, which was greater for those with higher levels of health anxiety. The higher hit rate for health words is partly mediated by the extent to which health words are evaluated as emotionally unpleasant, and this was stronger for (moderated by) those with higher levels of health anxiety. Consistent with the associative strength model, those with higher levels of health anxiety demonstrated faster PRTs when making emotional evaluations of health words compared to nonhealth words, while those lower in health anxiety were slower to evaluate health words. Emotional evaluations speed the recognition of health words for high health anxious individuals. These findings are discussed with respect to the wider literature on cognitive processes in health anxiety, automatic processing, implicit attitudes, and emotions in decision making.
Effect of higher frequency on the classification of steady-state visual evoked potentials
NASA Astrophysics Data System (ADS)
Won, Dong-Ok; Hwang, Han-Jeong; Dähne, Sven; Müller, Klaus-Robert; Lee, Seong-Whan
2016-02-01
Objective. Most existing brain-computer interface (BCI) designs based on steady-state visual evoked potentials (SSVEPs) primarily use low frequency visual stimuli (e.g., <20 Hz) to elicit relatively high SSVEP amplitudes. While low frequency stimuli could evoke photosensitivity-based epileptic seizures, high frequency stimuli generally show less visual fatigue and no stimulus-related seizures. The fundamental objective of this study was to investigate the effect of stimulation frequency and duty-cycle on the usability of an SSVEP-based BCI system. Approach. We developed an SSVEP-based BCI speller using multiple LEDs flickering with low frequencies (6-14.9 Hz) with a duty-cycle of 50%, or higher frequencies (26-34.7 Hz) with duty-cycles of 50%, 60%, and 70%. The four different experimental conditions were tested with 26 subjects in order to investigate the impact of stimulation frequency and duty-cycle on performance and visual fatigue, and evaluated with a questionnaire survey. Resting state alpha powers were utilized to interpret our results from the neurophysiological point of view. Main results. The stimulation method employing higher frequencies not only showed less visual fatigue, but it also showed higher and more stable classification performance compared to that employing relatively lower frequencies. Different duty-cycles in the higher frequency stimulation conditions did not significantly affect visual fatigue, but a duty-cycle of 50% was a better choice with respect to performance. The performance of the higher frequency stimulation method was also less susceptible to resting state alpha powers, while that of the lower frequency stimulation method was negatively correlated with alpha powers. Significance. These results suggest that the use of higher frequency visual stimuli is more beneficial for performance improvement and stability as time passes when developing practical SSVEP-based BCI applications.
Effect of higher frequency on the classification of steady-state visual evoked potentials.
Won, Dong-Ok; Hwang, Han-Jeong; Dähne, Sven; Müller, Klaus-Robert; Lee, Seong-Whan
2016-02-01
Most existing brain-computer interface (BCI) designs based on steady-state visual evoked potentials (SSVEPs) primarily use low frequency visual stimuli (e.g., <20 Hz) to elicit relatively high SSVEP amplitudes. While low frequency stimuli could evoke photosensitivity-based epileptic seizures, high frequency stimuli generally show less visual fatigue and no stimulus-related seizures. The fundamental objective of this study was to investigate the effect of stimulation frequency and duty-cycle on the usability of an SSVEP-based BCI system. We developed an SSVEP-based BCI speller using multiple LEDs flickering with low frequencies (6-14.9 Hz) with a duty-cycle of 50%, or higher frequencies (26-34.7 Hz) with duty-cycles of 50%, 60%, and 70%. The four different experimental conditions were tested with 26 subjects in order to investigate the impact of stimulation frequency and duty-cycle on performance and visual fatigue, and evaluated with a questionnaire survey. Resting state alpha powers were utilized to interpret our results from the neurophysiological point of view. The stimulation method employing higher frequencies not only showed less visual fatigue, but it also showed higher and more stable classification performance compared to that employing relatively lower frequencies. Different duty-cycles in the higher frequency stimulation conditions did not significantly affect visual fatigue, but a duty-cycle of 50% was a better choice with respect to performance. The performance of the higher frequency stimulation method was also less susceptible to resting state alpha powers, while that of the lower frequency stimulation method was negatively correlated with alpha powers. These results suggest that the use of higher frequency visual stimuli is more beneficial for performance improvement and stability as time passes when developing practical SSVEP-based BCI applications.
Elkan, Ann-Charlotte; Håkansson, Niclas; Frostegård, Johan; Cederholm, Tommy; Hafström, Ingiäld
2009-01-01
Patients with rheumatoid arthritis (RA) have an increased risk for cardiovascular disease (CVD) independent of traditional risk factors. The aim of this study was to analyze the associations between diet, body composition, lipids and atheroprotective natural antibodies against phosphorylcholine (anti-PC) in patients with RA. A total of 80 RA patients (76% women), mean age (standard deviation (SD)) 61.4 (12) years and median disease duration of 6 years, were assessed by food frequency questionnaire (FFQ), fatty acid profile in adipose tissue and whole-body dual energy x ray absorptiometry (DXA). Rheumatoid cachexia was defined as fat free mass index below the 25th percentile and fat mass index above the 50th percentile of a reference population. Blood lipids, oxidized low-density lipoprotein (oxLDL) and anti-PC levels were determined. The mean body mass index for the women and men was 25.0 and 27.0, respectively. Central obesity was found in 57% of the women (waist circumference >80 cm) and in 89% of the men (waist circumference >94 cm). In all, 18% of the women and 26% of the men had rheumatoid cachexia. These patients had significantly higher total cholesterol (P < 0.033), LDL (P < 0.029), and trendwise oxLDL (P = 0.056) as well as lower anti-PC IgM (P = 0.040), higher frequency of hypertension (69%) and metabolic syndrome (25%) than those without. The patients reported a high dietary intake of saturated fat, which partly correlated with fatty acid composition in adipose tissue and significantly with disease activity. However, patients with or without cachexia did not differ with respect to dietary fat intake or intake of Mediterranean-like diet. Additionally, patients on a Mediterranean-like diet had high levels of anti-PC (P < 0.001). About one in five patients with low-active RA displayed rheumatoid cachexia. This condition was associated with high levels of LDL cholesterol, low levels of atheroprotective anti-PC and high frequency of hypertension, which is of interest in the context of CVD in RA. The cachexia could not be related to diet fat intake. However, patients on a Mediterranean-like diet had high anti-PC levels in spite of similar frequency of cachexia. High anti-PC levels may provide some protection against CVD.
Kasparian, Nadine A; Bränström, Richard; Chang, Yu-mei; Affleck, Paul; Aspinwall, Lisa G; Tibben, Aad; Azizi, Esther; Baron-Epel, Orna; Battistuzzi, Linda; Bruno, William; Chan, May; Cuellar, Francisco; Debniak, Tadeusz; Pjanova, Dace; Ertmanski, Slawomir; Figl, Adina; Gonzalez, Melinda; Hayward, Nicholas K; Hocevar, Marko; Kanetsky, Peter A; Leachman, Sancy; Bergman, Wilma; Heisele, Olita; Palmer, Jane; Peric, Barbara; Puig, Susana; Schadendorf, Dirk; Gruis, Nelleke A; Newton-Bishop, Julia; Brandberg, Yvonne
2012-10-01
To examine the frequency and correlates of skin examination behaviors in an international sample of individuals at varying risk of developing melanoma. A cross-sectional, web-based survey. Data were collected from the general population over a 20-month period on behalf of the Melanoma Genetics Consortium (GenoMEL). A total of 8178 adults from Northern (32%), Central (33%), and Southern (14%) Europe, Australia (13%), and the United States (8%). Self-reported frequency of skin self-examination (SSE) and clinical skin examination (CSE). After adjustment for age and sex, frequency of skin examination was higher in both Australia (odds ratio [OR]SSE=1.80 [99% CI, 1.49-2.18]; ORCSE=2.68 [99% CI, 2.23-3.23]) and the United States (ORSSE=2.28 [99% CI, 1.76-2.94]; ORCSE=3.39 [99% CI, 2.60-4.18]) than in the 3 European regions combined. Within Europe, participants from Southern Europe reported higher rates of SSE than those in Northern Europe (ORSSE=1.61 [99% CI, 1.31-1.97]), and frequency of CSE was higher in both Central (ORCSE=1.47 [99% CI, 1.22-1.78]) and Southern Europe (ORCSE=3.46 [99% CI, 2.78, 4.31]) than in Northern Europe. Skin examination behavior also varied according to melanoma history: participants with no history of melanoma reported the lowest levels of skin examination, while participants with a previous melanoma diagnosis reported the highest levels. After adjustment for region, and taking into account the role of age, sex, skin type, and mole count, engagement in SSE and CSE was associated with a range of psychosocial factors, including perceived risk of developing melanoma; perceived benefits of, and barriers to, skin examination; perceived confidence in one's ability to engage in screening; and social norms. In addition, among those with no history of melanoma, higher cancer-related worry was associated with greater frequency of SSE. Given the strong association between psychosocial factors and skin examination behaviors, particularly among people with no history of melanoma, we recommend that greater attempts be made to integrate psycho-education into the fabric of public health initiatives and clinical care, with clinicians, researchers, and advocacy groups playing a key role in guiding individuals to appropriate tools and resources.
Effects of gaseous fluoride on Delicious and Golden Delicious apples
DOE Office of Scientific and Technical Information (OSTI.GOV)
Young, M.J.
1973-01-01
Atmospheric fluorides were monitored in apple and other fruit orchards around two adjacent sources of fluoride emissions. Delicious and Golden Delicious trees were fumigated with low (4.6-4.7 micrograms F/cu m) fluoride levels once, twice, or three times a week. However, both methods were adequate in the determination of the fluoride distribution pattern in the study area. Considerably higher levels of fluoride were detected at sampling sites downwind of the emission sources. Fluoride-induced tip necrosis on apple leaves was observed in one orchard where a mean seasonal limed filter paper value of 82.4 micrograms F/d sq m/mo and 22.5 F inmore » the washed foliage were recorded. Tip necrosis increased as the F level and frequency of exposure increased. Leaf respiration was inhibited at the lower but not the higher F fumigation level. Fruit respiration was stimulated to equal levels by the two F concentrations used. A trend toward increased inhibition of fruit ethylene production at lower exposure factors (concentration times time) was observed. The loss of green color in the skin of treated fruits was retarded relative to an increase in the F level and the exposure frequency. With the exception of leaf respiration, where an inverse relationship was found, the degree of response with respect to leaf injury, fruit respiration, and color were directly affected by the exposure factor used. Within the scope of this study, fruit shape, firmness, and soluble solids were not affected by the treatments.« less
Williams, Megan K.; Rundle, Andrew; Holmes, Darrell; Reyes, Marilyn; Hoepner, Lori A.; Barr, Dana B.; Camann, David E.; Perera, Frederica P.; Whyatt, Robin M.
2008-01-01
Background Widespread residential pesticide use throughout the United States has resulted in ubiquitous, low-level pesticide exposure. The mix of active pesticide ingredients is changing in response to 2000–2001 regulations restricting use of the organophosphorus insecticides chlorpyrifos and diazinon. Objectives We aimed to determine the impact of U.S. Environmental Protection Agency regulations on pest infestation levels, pesticide use, and pesticides measured in indoor air samples. METHODOLOGY: 511 pregnant women from innercity New York were enrolled between 2000 and 2006. Permethrin, a pyrethroid insecticide; piperonyl butoxide (PBO), a pyrethroid synergist; chlorpyrifos; and diazinon were measured in 48-hr prenatal personal air samples. Data on pest infestation and pesticide use were collected via questionnaire. Results Eighty-eight percent of women reported using pesticides during pregnancy; 55% reported using higher-exposure pesticide applications (spray cans, pest bombs and/or professional pesticide applicators). Self-reported pest sightings and use of higher-exposure applications increased significantly after the regulations were implemented (p < 0.001). PBO, cis-, and trans-permethrin were detected in 75, 19, and 18% of personal air samples, respectively. Detection frequencies of PBO and cis- and trans-permethrin increased significantly over time (p < 0.05 controlling for potential confounders). Levels and/or detection frequencies of these compounds were significantly higher among mothers reporting use of high exposure pesticide applications (p ≤ 0.05). Chlorpyrifos and diazinon levels decreased significantly over time (p < 0.001). Conclusion In this cohort, pest infestations, use of pesticides, and use of permethrin appear to increase after the residential restriction of organophosphorus insecticides. This is one of the first studies to document widespread residential exposure to PBO. PMID:19079720
Chaudhary, Nagendra; Kabra, Madhulika; Gulati, Sheffali; Gupta, Yogendra Kumar; Pandey, Ravindra Mohan; Bhatia, Bal Dev
2016-05-14
Phenytoin, mainly metabolized by cytochrome P450 enzyme system, has a narrow therapeutic index and may have adverse effects due to inter-individual variation in the dose requirement and genetic polymorphisms. This cross-sectional study was done to study the prevalence of cytochrome P450 CYP2C9 polymorphisms in Indian epileptic children and to see the effect of polymorphisms on serum levels in epileptic children on phenytoin monotherapy. We studied 89 epileptic children of North Indian population, randomly selected, to see the genotypic and allelic frequency of CYP2C9 and its association with drug levels on phenytoin monotherapy. Analysis was done using STATA 9 Software. The results were analyzed as prevalence at 95 % C.I. (Confidence Interval). The difference in mean phenytoin serum levels between wild and mutant alleles was tested using Student`s T test for independent samples. P value less than 0.05 was considered statistically significant. CYP2C9*1, *2 & *3 allelic frequencies were 85.4, 4.5 and 10.1 % respectively. CYP2C9*3 allelic group showed significantly higher serum phenytoin levels compared to the wild variants (P = 0.009). There was no statistically significant difference in the dose received (P = 0.12) and side effects of CYP2C9*2 and CYP2C9*3 genotypes (P = 0.442 and 0.597 respectively) when compared with wild variant. CYP2C9*3 is more common than *2 in the present study. All the polymorphisms demonstrated in our study were heterozygous with no homozygosity. Serum phenytoin levels are higher in polymorphic groups (*3) which suggest their poor metabolizing nature. Genotyping may help to avoid toxicity and concentration-dependent adverse effects.
Van Larebeke, Nicolas; Koppen, Gudrun; Nelen, Vera; Schoeters, Greet; Van Loon, Herman; Albering, Harma; Riga, Louk; Vlietinck, Robert; Kleinjans, Jos
2004-01-01
Biomarkers were measured in residents of Wilrijk and Hoboken, industrial suburbs of the city of Antwerp, and of Peer, a rural municipality in Flanders, Belgium. Persons with known occupational exposures to toxic compounds or commuting over long distances were excluded. Here, we report the hypoxanthine phosphoribosyltransferase gene (HPRT) variant frequencies for 99 non-smoking women aged 50-65 years. HPRT values above the detection limit (V(fpos) values) were observed for 43 subjects (21 from Peer, 22 from Antwerp). The median (10th to 90th percentiles) HPRT variant frequency (V(fpos)) in peripheral lymphocytes was 9.59 (3.44-56.99) for Peer and 3.57 (1.57-13.96) for Antwerp. The V(fpos) value was significantly higher in Peer than in Antwerp, both in terms of crude data (p=0.011) and after correction for age, level of education, smoking status, serum level of selenium and body mass index through analysis of covariance (p=0.011). For the total study population, serum lead concentration showed a non-significant positive correlation with lnV(fpos). In addition, subjects with a blood lead concentration above the median tended to have higher V(fpos) values (9.45x10(-6) for 'high' group versus 5.21x10(-6) for 'low' group; p=0.077 after correction for confounding). Subjects with a serum selenium level above the median tended to have lower V(fpos) values (4.99x10(-6) for 'high' group versus 9.83x10(-6) for 'low' group; p=0.051 after correction for confounding). These data are consistent with an indirect genotoxic effect of lead and with an antimutagenic effect of selenium.
Anthony, James C.; Saito, Luis Paulo; de Andrade, Arthur Guerra; Kutschenko, Andressa; Viana, Maria Carmen; Wang, Yuan-Pang; Martins, Silvia S.; Andrade, Laura Helena
2014-01-01
Background Research conducted in high-income countries has investigated influences of socioeconomic inequalities on drinking outcomes such as alcohol use disorders (AUD), however, associations between area-level neighborhood social deprivation (NSD) and individual socioeconomic status with these outcomes have not been explored in Brazil. Thus, we investigated the role of these factors on drink-related outcomes in a Brazilian population, attending to male-female variations. Methods A multi-stage area probability sample of adult household residents in the São Paulo Metropolitan Area was assessed using the WHO Composite International Diagnostic Interview (WMH-CIDI) (n = 5,037). Estimation focused on prevalence and correlates of past-year alcohol disturbances [heavy drinking of lower frequency (HDLF), heavy drinking of higher frequency (HDHF), abuse, dependence, and DMS-5 AUD] among regular users (RU); odds ratio (OR) were obtained. Results Higher NSD, measured as an area-level variable with individual level variables held constant, showed an excess odds for most alcohol disturbances analyzed. Prevalence estimates for HDLF and HDHF among RU were 9% and 20%, respectively, with excess odds in higher NSD areas; schooling (inverse association) and low income were associated with male HDLF. The only individual-level association with female HDLF involved employment status. Prevalence estimates for abuse, dependence, and DSM-5 AUD among RU were 8%, 4%, and 8%, respectively, with excess odds of: dependence in higher NSD areas for males; abuse and AUD for females. Among RU, AUD was associated with unemployment, and low education with dependence and AUD. Conclusions Regular alcohol users with alcohol-related disturbances are more likely to be found where area-level neighborhood characteristics reflect social disadvantage. Although we cannot draw inferences about causal influence, the associations are strong enough to warrant future longitudinal alcohol studies to explore causal mechanisms related to the heterogeneous patterns of association and male-female variations observed herein. Hopefully, these findings may help guide future directions for public health. PMID:25272008
Ahmed, Abul-Fotouh; Alshahrani, Saad; Morgan, Anthony; Gabr, Ahmed H; Abdel-Razik, Mohamed; Daoud, Abdallah
2017-12-01
To evaluate the frequency of sex-enhancing medications (S-EM) use and to investigate the demographics and sexual characteristics of the S-EM users amongst a Saudi Arabian male population. A cross-sectional sample of 1176 Saudi Arabian men was recruited using a web-based survey between 1 January and 1 April 2015. The survey included multiple open and closed questions to assess the frequency of S-EM use; and demographics, clinical, and sexual characteristics of S-EM users, as well as their perceptions of S-EM. Amongst the participants, 1008 were sexually active and included in the data analysis. Of the sexually active participants, 402 (39.9%) reported S-EM use in the form of herbal or phosphodiesterase type 5 inhibitors at some time in their lives. Comparing S-EM users with S-EM non-users, the S-EM users had a number of demographic and sexual characteristics including: higher education level, higher income, smoking, more than one sexual partner, longer sexual activity duration, higher frequency of sexual intercourse, and lower sexual satisfaction level. Most of the S-EM users (82.1%) bought S-EM without a medical prescription and 62.5% had used them recreationally. In all, 52% of respondents used S-EM to treat ED and 69% of those who used it recreationally reported enhancement of erection with S-EM usage. Demographic and sexual characteristics of S-EM users and the attitude of the users towards the S-EM were identified amongst a Saudi Arabian male population.
Huang, Ying-Shuo; Feng, Ying-Chao; Zhang, Jian; Bai, Li; Huang, Wei; Li, Min; Sun, Ying
2015-01-01
To evaluate the impact of chronic obstructive pulmonary disease (COPD) on left ventricular (LV) diastolic function in hospitalized elderly patients. This was a case-control observational study of 148 consecutive hospitalized elderly patients (≥65 years old): 73 subjects without COPD as controls and 75 patients with COPD. Mild-to-moderate COPD was defined as stages 1 and 2, while severe and very severe COPD was defined as stages 3 and 4, according to the Global Initiative for Chronic Obstructive Lung Disease guidelines. Clinical characteristics and echocardiographic parameters were analyzed and compared. Compared with the control group, patients with COPD had a higher frequency of LV diastolic dysfunction and heart failure with preserved ejection fraction. Smoking frequency, frequency of cerebrovascular diseases and diabetes, and serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were higher in the COPD group (all P<0.05). COPD patients showed more abnormalities in diastolic function (E/e': 11.51±2.50 vs 10.42±3.25, P=0.047), but no differences in systolic function and right ventricular function (all P>0.05). Patients with severe/very severe COPD showed no differences in LV diastolic function compared to patients with mild/moderate COPD (P>0.05), but serum NT-proBNP levels were higher in severe/very severe COPD (P<0.05). Results suggest that early-stage COPD may have an impact on the LV diastolic function. Severe COPD mainly affected right ventricular function. In hospitalized elderly patients with COPD, LV diastolic dysfunction should be taken into account together with right ventricular function.
Investigation of ABCA1 C69T polymorphism in patients with type 2 diabetes mellitus.
Ergen, H Arzu; Zeybek, Umit; Gök, Ozlem; Karaali, Z Ermis
2012-01-01
Non insulin dependent diabetes mellitus is the most common type of diabetes. Genetic factors, lipid profiles, hypertension are potential risk factors for diabetes mellitus. Adenosine binding cassette transporter proteins 1 (ABCA1) plays a role in cholesterol metabolism, especially high density lipoprotein (HDL-cholesterol). There are multiple mechanisms by which HDL-cholesterol can be atheroprotective, it is clear that the relative activity of ABCA1 plays a major role. We aimed to investigate association of ABCA1 C69T gene polymorphism with lipid levels in Turkish type 2 diabetic patients. After isolation of DNA by ethanol precipitation we determined ABCA1 gene polymorphism by using polimerase chain reaction--restriction fragment lenght polymorphism (PCR-RFLP) method in 107 type 2 diabetic patients and 50 healthy controls. We have observed that the frequency of TT genotype is significantly higher in healthy controls compared to patients (14% vs. 3%; P = 0.008). Also frequency of T allele was higher in controls than in patients (34% vs. 21%; P = 0.020; OR (95% CI) = 0.52 (0.30-0.88)). There was no association of lipid levels and ABCA1 C69T polymorphism subgroups. We have found significantly higher frequency of both T allele and genotype in control group when compared to patients that made us think that T allele may be a protective factor against diabetes mellitus. But, we could not find a relationship between genotypes and lipid concentrations in our two groups. Larger studies will help us to understand the relationship between ABCA1 C69T genotype and lipid parameters in diabetes mellitus.
Sickle haemoglobin, haemoglobin C and malaria mortality feedbacks.
Gonçalves, Bronner P; Gupta, Sunetra; Penman, Bridget S
2016-01-12
Sickle haemoglobin (HbS) and haemoglobin C (HbC) are both caused by point mutations in the beta globin gene, and both offer substantial malaria protection. Despite the fact that the blood disorder caused by homozygosity for HbC is much less severe than that caused by homozygosity for HbS (sickle cell anaemia), it is the sickle mutation which has come to dominate many old-world malarious regions, whilst HbC is highly restricted in its geographical distribution. It has been suggested that this discrepancy may be due to sickle cell heterozygotes enjoying a higher level of malaria protection than heterozygotes for HbC. A higher fitness of sickle cell heterozygotes relative to HbC heterozygotes could certainly have allowed the sickle cell allele to spread more rapidly. However, observations that carrying either HbC or HbS enhances an individual's capacity to transmit malaria parasites to mosquitoes could also shed light on this conundrum. A population genetic model was used to investigate the evolutionary consequences of the strength of malaria selection being correlated with either HbS frequency or HbC frequency. If the selection pressure from malaria is positively correlated with the frequency of either HbS or HbC, it is easier for HbS to succeed in the competitive interaction between the two alleles. A feedback process whereby the presence of variant haemoglobins increases the level of malaria selection in a population could have contributed to the global success of HbS relative to HbC, despite the former's higher blood disorder cost.
Casanova-Rosado, J F; Vallejos-Sánchez, A A; Minaya-Sánchez, M; Medina-Solís, C E; De La Rosa-Santillana, R; Márquez-Corona, M de L; Maupomé, G
2013-01-01
To determine the prevalence of daily tooth brushing and evaluate some variables associated. A cross-sectional study was carried out in 320 schoolchildren six to nine years old in Campeche, Mexico. Information on sociodemographic and socio-economic variables, oral hygiene practices and attitudes were collected through a questionnaire. The frequency of tooth brushing was categorized as "0" = fewer than seven times/week, "1" = at least once a day. In the analysis, nonparametric tests were used. Mean age was 6.99 +/- 1.00 years, 52.5% were boys. The prevalence of daily tooth brushing was 81.6%. In bivariate analysis, the prevalence of tooth brushing was higher (p < 0.05) among the children of mothers with higher schooling (9.80 years vs 8.47 years, p < 0.05), and in younger children (84.6% in 6-7-year olds vs 71.2% in 8-9-year olds, p < 0.05). A slight, non-significant association (p < 0.10) was noted between the current frequency of tooth brushing and an earlier age when the child first started brushing with toothpaste. There were no statistically significant differences (p > 0.05) in the frequency of tooth brushing by gender or by the mother's attitude toward the oral health of her child. The prevalence of daily tooth brushing was high compared to other studies. Mother's maximum level of schooling (as an indicator of socio-economic position) was associated with higher frequency of tooth brushing. Maternal characteristics are associated with the oral health behaviour of their children.
Burgos Peláez, Rosa; Joaquin Ortiz, Clara; Vaqué Crusellas, Cristina
2017-05-08
Disease-related malnutrition is highly prevalent in pathologies commonly integrating care complexity. Healthcare models for complexity must include malnutrition detection and approaches, since it is a key factor which has great impact on the patient’s evolution and the consumption of healthcare resources. Malnourished patients present higher hospitalization, complication and mortality rates, higher demand of post-discharge social resources and higher hospital readmission frequency. Detecting malnutrition is necessary to implement a nutritional care program which might be used in any assistance level. The integration of health and social care and the development of information tools which are shared by the different assistance agents has allowed the development of a program for the management of disease-related malnutrition in patients with clinical complexity in Catalonia.
Rupp, M; McConnell, D S; Smither, J A
2012-01-01
Distracted driving has been shown to be a safety issue in numerous studies. To combat this problem, in-vehicle technology, legislation, media interventions, and other methods have been proposed and attempted. However research indicates that the drivers themselves may circumvent, ignore, or not be able to react in time for these interventions to be effective. Therefore research into training programs for drivers may improve reaction time under distraction. Research indicates that action game players have faster reaction times and more attentional resources than non-players on paper-based tests. However, transferability to driving has not been studied yet. This paper outlines a study to determine if action game players perform better at a driving task based on frequency of game-play. Participants will be placed into two groups of play (high vs. low) and tested against two levels of distraction (none vs. phone conversation). It is expected that participants who play higher frequency of action games will perform better under distraction than lower frequency players. Driver performance, conversation recall, frequency and durations of eye fixations will be analyzed based on previous research which has validated those variables as a measure of distraction and higher workload.
Sister chromatid exchange rate and alkaline comet assay scores in patients with ovarian cancer.
Baltaci, Volkan; Kayikçioğlu, Fulya; Alpas, Idil; Zeyneloğlu, Hulusi; Haberal, Ali
2002-01-01
Sister chromatid exchange (SCE) frequencies were studied in patients with different types of ovarian malignancies and in healthy volunteers. The level of DNA damage in patients with ovarian malignancy and control subjects has also been studied by alkaline single cell gel electrophoresis (SCGE), also known as the comet assay. Peripheral blood was collected from 30 patients after histological confirmation of malignancy and 20 healthy female volunteers. The cells were evaluated according to their grade of damage. We found that the sister chromatid exchange frequencies of cancer cases were significantly greater than that of controls (P < 0.001). The frequency of exchange in chromosomal groups A, B, and C, which include chromosomes 1-12, was higher than that of the other chromosomal groups in both groups. Comparison of the results of the alkaline comet assay in patient and control subjects showed a significant difference in the number of damaged cells. The frequency of limited migrated and extensive migrated cells in the women with ovarian malignancies was higher than that of control women (P < 0.001). SCE and SCGE can be used successfully to monitor DNA damage in women with ovarian cancer.
Sheppard, Asher R; Swicord, Mays L; Balzano, Quirino
2008-10-01
The complexity of interactions of electromagnetic fields up to 10(12) Hz with the ions, atoms, and molecules of biological systems has given rise to a large number of established and proposed biophysical mechanisms applicable over a wide range of time and distance scales, field amplitudes, frequencies, and waveforms. This review focuses on the physical principles that guide quantitative assessment of mechanisms applicable for exposures at or below the level of endogenous electric fields associated with development, wound healing, and excitation of muscles and the nervous system (generally, 1 to 10(2) V m(-1)), with emphasis on conditions where temperature increases are insignificant (<1 K). Experiment and theory demonstrate possible demodulation at membrane barriers for frequencies < or =10 MHz, but not at higher frequencies. Although signal levels somewhat below system noise can be detected, signal-to-noise ratios substantially less than 0.1 cannot be overcome by cooperativity, signal averaging, coherent detection, or by nonlinear dynamical systems. Sensory systems and possible effects on biological magnetite suggest paradigms for extreme sensitivity at lower frequencies, but there are no known radiofrequency (RF) analogues. At the molecular level, vibrational modes are so overdamped by water molecules that excitation of molecular modes below the far infrared cannot occur. Two RF mechanisms plausibly may affect biological matter under common exposure conditions. For frequencies below approximately 150 MHz, shifts in the rate of chemical reactions can be mediated by radical pairs and, at all frequencies, dielectric and resistive heating can raise temperature and increase the entropy of the affected biological system.
Bhagat, Shaum P.; Bass, Johnnie K.; White, Stephanie T.; Qaddoumi, Ibrahim; Wilson, Matthew W.; Wu, Jianrong; Rodriguez-Galindo, Carlos
2016-01-01
Objective Carboplatin is a common chemotherapy agent with potential ototoxic side effects that is used to treat a variety of pediatric cancers, including retinoblastoma. Retinoblastoma is a malignant tumor of the retina that is usually diagnosed in young children. Distortion-product otoacoustic emission tests offer an effective method of monitoring for ototoxicity in young children. This study was designed to compare measurements of distortion-product otoacoustic emissions obtained before and after several courses of carboplatin chemotherapy in order to examine if (a) mean distortion-product otoacoustic emission levels were significantly different; and (b) if criterion reductions in distortion-product otoacoustic emission levels were observed in individual children. Methods A prospective repeated measures study. Ten children with a median age of 7.6 months (range, 3–72 months) diagnosed with unilateral or bilateral retinoblastoma were examined. Distortion-product otoacoustic emissions were acquired from both ears of the children with 65/55 dB SPL primary tones (f2= 793–7996 Hz) and a frequency resolution of 3 points/octave. Distortion-product otoacoustic emission levels in dB SPL were measured before chemotherapy treatment (baseline measurement) and after 3–4 courses of chemotherapy (interim measurement). Comparisons were made between baseline and interim distortion-product otoacoustic emission levels (collapsed across ears). Evidence of ototoxicity was based on criterion reductions (≥ 6 dB) in distortion-product otoacoustic emission levels. Results Significant differences between baseline and interim mean distortion-product otoacoustic emission levels were only observed at f2=7996 Hz. Four children exhibited criterion reductions in distortion-product otoacoustic emission levels. Conclusions Mean distortion-product otoacoustic emission levels at most frequencies were not changed following 3–4 courses of carboplatin chemotherapy in children with retinoblastoma. However, on an individual basis, children receiving higher doses of carboplatin exhibited criterion reductions in distortion-product otoacoustic emission level at several frequencies. These findings suggest that higher doses of carboplatin affect outer hair cell function, and distortion-product otoacoustic emission tests can provide useful information when monitoring children at risk of developing carboplatin ototoxicity. PMID:20667604
Source of seed fluctuations for electromagnetic ion cyclotron waves in Earth's magnetosphere
NASA Astrophysics Data System (ADS)
Gamayunov, K. V.; Engebretson, M. J.; Zhang, M.; Rassoul, H. K.
2015-06-01
We consider a nonlinear wave energy cascade from the low frequency range into the higher frequency domain of electromagnetic ion cyclotron (EMIC) wave generation as a possible source of seed fluctuations for EMIC wave growth due to the ion cyclotron instability in Earth's magnetosphere. The presented theoretical analysis shows that energy cascade from the Pc 4-5 frequency range (2-22 mHz) into the range of Pc 1-2 pulsations (0.1-5 Hz), i.e. into the frequency range of EMIC waves, is able to supply the needed level of seed fluctuations that guarantees growth of EMIC waves up to the observable level during one pass through the near equatorial region where the ion cyclotron instability takes place. We also analyze the magnetic field data from the Polar and Van Allen Probes spacecraft to test the suggested nonlinear mechanism. In this initial study we restrict our analysis to magnetic fluctuation spectra only. We do not analyze the third-order structure function, but judge whether a nonlinear energy cascade is present or whether it is not by only analyzing the appearance of power-law distributions in the low-frequency part of the magnetic field spectra. While the power-law spectrum alone does not guarantee that a nonlinear cascade is present, the power-law distribution is a strong indication of the possible development of a nonlinear cascade. Our analysis shows that a nonlinear energy cascade is indeed observed in both the outer and inner magnetosphere data, and EMIC waves are growing from this nonthermal background. All the analyzed data are in good agreement with the theoretical model presented in this study. Overall, the results of this study support a nonlinear energy cascade in Earth's magnetosphere as a mechanism which is responsible for supplying seed fluctuating energy in the higher frequency domain where EMIC waves grow due to the ion cyclotron instability.
Ding, Zhili; Kong, Youqin; Zhang, Yixiang; Li, Jingfen; Cao, Fang; Zhou, Junbo; Ye, Jinyun
2017-09-01
Feeding frequency is important for the improvement of growth performance and immunity of aquatic animals. In this study, the effect of feeding frequency on growth, body composition, antioxidant status and mRNA expression of immunodependent genes before or after ammonia-N stress was examined in Macrobrachium nipponense. Prawns were randomly assigned to one of five feeding frequencies (1, 2, 3, 4 and 6 times/day) following the same ration size over an 8-week growth trial. After the feeding trial, prawns were challenged by ammonia-N. The weight gain of prawns fed with 3-6 times/day was significantly higher than that of prawns fed with 1 time/day. The best feed conversion ratio was obtained from prawns fed with 3-6 times/day. Body crude lipid with feeding frequency of 3, 4 or 6 times/day was quite lower than that with 1 time/day. High feeding frequency (6 times/day) induced significantly elevated hepatopancreas super oxide dismutase and catalase activities. The malondialdehyde level in prawns fed with 6 times/day was also significantly increased, which was higher than that of prawns fed with other feeding frequency. mRNA expression of toll like receptor 3 and myeloid differentiation primary response protein MyD88 was promoted by feeding frequency from 3 to 4 time/day but inhibited by high or low feeding frequency. Similar mRNA expression variation trends of the two genes were observed in prawns after ammonia-N stress. After ammonia-N challenge, the highest cumulative mortality was observed in prawns fed with 6 times/day, which was significantly higher than that of prawns fed with 2-4 times/day. These findings demonstrate that (1) too high feeding frequency induced oxidative stress and malondialdehyde accumulation, negatively affecting the health status of prawns and reduced its resistance to ammonia-N stress; (2) the optimal feeding frequency to improve growth and immune response of this species at juvenile stage is 3-4 times/day; (3) considering costs of labour, a feeding frequency of 3 times/day is recommended for this prawn. Copyright © 2017 Elsevier Ltd. All rights reserved.
Tsujino, Jiromaru; Hongoh, Misugi; Yoshikuni, Masafumi; Hashii, Hidekazu; Ueoka, Tetsugi
2004-04-01
The welding characteristics of 27, 40 and 67 kHz ultrasonic plastic welding systems that are driven at only the fundamental-resonance frequency vibration were compared, and also those of the welding systems that were driven at the fundamental and several higher resonance frequencies simultaneously were studied. At high frequency, welding characteristics can be improved due to the larger vibration loss of plastic materials. For welding of rather thin or small specimens, as the fundamental frequency of these welding systems is higher and the numbers of driven higher frequencies are driven simultaneously, larger welded area and weld strength were obtained.
Complementary modulation of N2 and CRN by conflict frequency.
Grützmann, Rosa; Riesel, Anja; Klawohn, Julia; Kathmann, Norbert; Endrass, Tanja
2014-08-01
The present study investigated the modulation of the N2 and the correct-related negativity (CRN) by conflict frequency. Conflict costs, as measured by reaction times and error rate, were reduced with increasing conflict frequency, indicating improved conflict resolution. N2 amplitudes in incompatible trials increased with higher conflict frequency, while postresponse CRN amplitudes decreased. In concert with behavioral findings of reduced conflict costs and greater interference suppression, the increase of N2 might reflect enhanced conflict resolution during stimulus processing. The CRN, however, might reflect postresponse implementation of cognitive control, which is reduced when conflict is already adequately resolved during stimulus processing. Furthermore, N2 and CRN in incompatible trials were inversely related on the between- and within-subject level, implying that the two modes of implementing cognitive control are applied complementarily. Copyright © 2014 Society for Psychophysiological Research.
NASA Astrophysics Data System (ADS)
Li, B.; Zhao, L.; Zhang, Y. B.; Zheng, Q.; Zhao, Y.; Yao, Y.
2013-03-01
Efficient and compact green-yellow laser output at 543 nm is generated by intracavity frequency doubling of a CW diode-pumped Nd:LuVO4 laser at 1086 nm under the condition of suppressing the higher gain transition near 1064 nm. With 16 W of diode pump power and the frequency-doubling crystal LBO, as high as 2.17 W of CW output power at 543 nm is achieved, corresponding to an optical-to-optical conversion efficiency of 13.6% and the output power stability over 8 hours is better than 2.86%. To the best of our knowledge, this is the highest watt-level laser at 543 nm generated by intracavity frequency doubling of a diode pumped Nd:LuVO4 laser at 1086 nm.
Enteroparasitoses and Toxocarosis Affecting Children from Mar del Plata City, Argentina.
Lavallén, Carla; Brignani, Beatriz; Riesgo, Karina; Rojas, Amalia; Colace, Gabriela; Biscaychipi, Martín; Chicote, Estela; Giuntini, Cristian; Kifer, Mariela; Del Río, María Eugenia; Denegri, Guillermo; Dopchiz, Marcela
2017-06-01
This study evaluated the existence of enteroparasitoses and toxocarosis in children of peripheral (PC) and urban communities (UC) from Mar del Plata city (Argentina) and their associations with socio-environmental conditions. A Parasite Vulnerability Index (PVI) was elaborated using variables such as overcrowding, floor type, drinking water source, wastewater disposal, solid waste disposal, presence of animals and schooling level. The PC evidenced statistically significant higher frequencies of families with high (38.9%) and medium (55.5%) PVI, while in the UC low PVI (93%) was the most frequent. A statistically significant higher frequency of PC children was parasitized (30.2 vs. 14.5%; χ 2 Pearson = 5.21; P < 0.05), presented higher parasite frequencies, specific richness, parasitic loads, and they also evidenced polyparasitism. The Multiple Correspondence Analysis (MCA) showed associations between PC-parasitized children, overcrowding and contact with pets and farm animals. The ELISA test to the specified determination of Toxocara canis IgG was reactive in a statistically significant higher proportion of PC children than the UC (55 vs. 8.5%; χ 2 = 30.5; P < 0.01). The MCA associated PC reactive children, not adequate hand washing, moderate and hypereosinophilia and contact with pets and farm animals. Deficient socio-environmental conditions became children more vulnerable to get enteroparasitoses and toxocarosis in the PC than in the UC.
Nandy, Bodhisatta; Gupta, Vanika; Sen, Sharmi; Udaykumar, Niveda; Samant, Manas Arun; Ali, Syed Zeeshan; Prasad, Nagaraj Guru
2013-09-28
Interlocus conflict predicts (a) evolution of traits, beneficial to males but detrimental to females and (b) evolution of aging and life-span under the influence of the cost of bearing these traits. However, there are very few empirical investigations shedding light on these predictions. Those that do address these issues, mostly reported response of male reproductive traits or the lack of it and do not address the life-history consequence of such evolution. Here, we test both the above mentioned predictions using experimental evolution on replicate populations of Drosophila melanogaster. We present responses observed after >45 generations of altered levels of interlocus conflict (generated by varying the operational sex ratio). Males from the male biased (high conflict, M-regime) regime evolved higher spontaneous locomotor activity and courtship frequency. Females exposed to these males were found to have higher mortality rate. Males from the female biased regime (low conflict, F-regime) did not evolve altered courtship frequency and activity. However, progeny production of females continuously exposed to F-males was significantly higher than the progeny production of females exposed to M-males indicating that the F-males are relatively benign towards their mates. We found that males from male biased regime lived shorter compared to males from the female biased regime. F-males (evolving under lower levels of sexual conflict) evolved decreased mate harming ability indicating the cost of maintenance of the suit of traits that cause mate-harm. The M-males (evolving under higher levels sexual conflict) caused higher female mortality indicating that they had evolved increased mate harming ability, possibly as a by product of increased reproduction related activity. There was a correlated evolution of life-history of the M and F-males. M-regime males lived shorter compared to the males from F-regime, possibly due to the cost of investing more in reproductive traits. In combination, these results suggest that male reproductive traits and life-history traits can evolve in response to the altered levels of interlocus sexual conflict.
A multistream model of visual word recognition.
Allen, Philip A; Smith, Albert F; Lien, Mei-Ching; Kaut, Kevin P; Canfield, Angie
2009-02-01
Four experiments are reported that test a multistream model of visual word recognition, which associates letter-level and word-level processing channels with three known visual processing streams isolated in macaque monkeys: the magno-dominated (MD) stream, the interblob-dominated (ID) stream, and the blob-dominated (BD) stream (Van Essen & Anderson, 1995). We show that mixing the color of adjacent letters of words does not result in facilitation of response times or error rates when the spatial-frequency pattern of a whole word is familiar. However, facilitation does occur when the spatial-frequency pattern of a whole word is not familiar. This pattern of results is not due to different luminance levels across the different-colored stimuli and the background because isoluminant displays were used. Also, the mixed-case, mixed-hue facilitation occurred when different display distances were used (Experiments 2 and 3), so this suggests that image normalization can adjust independently of object size differences. Finally, we show that this effect persists in both spaced and unspaced conditions (Experiment 4)--suggesting that inappropriate letter grouping by hue cannot account for these results. These data support a model of visual word recognition in which lower spatial frequencies are processed first in the more rapid MD stream. The slower ID and BD streams may process some lower spatial frequency information in addition to processing higher spatial frequency information, but these channels tend to lose the processing race to recognition unless the letter string is unfamiliar to the MD stream--as with mixed-case presentation.
Volunteering and Psychological Well-Being among Young-Old Adults: How Much Is Too Much?
ERIC Educational Resources Information Center
Windsor, Timothy D.; Anstey, Kaarin J.; Rodgers, Bryan
2008-01-01
Purpose: Research concerned with the relationship between volunteer activity and psychological well-being has typically reported higher levels of well-being among older adult volunteers relative to nonvolunteers. However, few studies have examined nonlinear associations between frequency of volunteer activity and well-being. We examined nonlinear…
Promoting Knowledge of Climate Change (CC) amongst Nigerians: Implications for Education Managers
ERIC Educational Resources Information Center
Akpomi, Margaret E.; Vipene, Joseph
2016-01-01
Rising sea levels, due to thermal expansion of the ocean, and higher frequency and intensity of coastal and inland storms threaten coastal communities worldwide. The implementation of pro-active, planned adaptation to reduce community vulnerability is strongly dependent upon people's awareness of the threat posed to their communities at the local…
Neuro-otologic symptoms in patients with type 2 diabetes mellitus.
Jáuregui-Renaud, Kathrine; Sánchez, Blanca; Ibarra Olmos, Alicia; González-Barcena, David
2009-06-01
To assess the prevalence of balance symptoms in type-2 diabetes mellitus (DM2), at the first level of health care. Compared to 101 controls, 101 patients showed a higher frequency of all the symptoms investigated through a standardized questionnaire (p<0.01). In DM2 patients, balance symptoms should be intentionally investigated.
Take Anything Else, but Leave My Classroom FM System!
ERIC Educational Resources Information Center
Nelson, Denise Grau; Schmidt, Michele
1993-01-01
FM (frequency modulation) classroom amplification systems are described. Advantages for students with only minimal hearing losses as well as those more seriously affected are noted. Research on FM classroom systems and input from 20 teachers support the use of this technology with students who need a slightly higher volume level of instruction.…
Building an EEG-fMRI Multi-Modal Brain Graph: A Concurrent EEG-fMRI Study
Yu, Qingbao; Wu, Lei; Bridwell, David A.; Erhardt, Erik B.; Du, Yuhui; He, Hao; Chen, Jiayu; Liu, Peng; Sui, Jing; Pearlson, Godfrey; Calhoun, Vince D.
2016-01-01
The topological architecture of brain connectivity has been well-characterized by graph theory based analysis. However, previous studies have primarily built brain graphs based on a single modality of brain imaging data. Here we develop a framework to construct multi-modal brain graphs using concurrent EEG-fMRI data which are simultaneously collected during eyes open (EO) and eyes closed (EC) resting states. FMRI data are decomposed into independent components with associated time courses by group independent component analysis (ICA). EEG time series are segmented, and then spectral power time courses are computed and averaged within 5 frequency bands (delta; theta; alpha; beta; low gamma). EEG-fMRI brain graphs, with EEG electrodes and fMRI brain components serving as nodes, are built by computing correlations within and between fMRI ICA time courses and EEG spectral power time courses. Dynamic EEG-fMRI graphs are built using a sliding window method, versus static ones treating the entire time course as stationary. In global level, static graph measures and properties of dynamic graph measures are different across frequency bands and are mainly showing higher values in eyes closed than eyes open. Nodal level graph measures of a few brain components are also showing higher values during eyes closed in specific frequency bands. Overall, these findings incorporate fMRI spatial localization and EEG frequency information which could not be obtained by examining only one modality. This work provides a new approach to examine EEG-fMRI associations within a graph theoretic framework with potential application to many topics. PMID:27733821
Skof, B; Strojnik, V
2006-03-01
The aim of this study was to determine the influence of intensive aerobic running on some muscle contractile characteristics and the dynamics of their recovery during a 2 hour period afterwards. Seven well trained runners performed a 6 km run at anaerobic threshold (V(OBLA)). Knee torque during single twitch, low and high frequency electrical stimulation (ES), maximum voluntary knee extension, and muscle activation level test of the quadriceps femoris muscles were measured before and immediately after the run, and at several time points during a 120 minute interval that followed the run. After exercise, the mean (SE) maximum twitch torque (T(TW)) and torque at ES with 20 Hz (low frequency ES; T(F20)) dropped by 14.1 (5.1)% (p<0.05) and 20.6 (7.9)% (p<0.05) respectively, while torque at stimulation with 100 Hz (high frequency ES; T(F100)), maximum isometric knee extension torque (maximum voluntary contraction torque; T(MVC)), and activation level did not change significantly. Twitch contraction time was shortened by 8 (2)% (p<0.05). Ten minutes after the run, T(TW) was 40% higher than immediately after the run and 10% (p<0.05) higher than before the run. T(F20), T(F100), and T(MVC) remained lower for 60 minutes (p<0.05) than before the run. A 6 km continuous run at V(OBLA) caused peripheral fatigue by impairing excitation-contraction coupling. Twitch torque recovered very quickly. However, the process of torque restoration at maximum isometric knee extension torque and at high and low frequency ES took much longer.
Narasimhan, S; Chiel, H J; Bhunia, S
2011-04-01
Implantable microsystems for monitoring or manipulating brain activity typically require on-chip real-time processing of multichannel neural data using ultra low-power, miniaturized electronics. In this paper, we propose an integrated-circuit/architecture-level hardware design framework for neural signal processing that exploits the nature of the signal-processing algorithm. First, we consider different power reduction techniques and compare the energy efficiency between the ultra-low frequency subthreshold and conventional superthreshold design. We show that the superthreshold design operating at a much higher frequency can achieve comparable energy dissipation by taking advantage of extensive power gating. It also provides significantly higher robustness of operation and yield under large process variations. Next, we propose an architecture level preferential design approach for further energy reduction by isolating the critical computation blocks (with respect to the quality of the output signal) and assigning them higher delay margins compared to the noncritical ones. Possible delay failures under parameter variations are confined to the noncritical components, allowing graceful degradation in quality under voltage scaling. Simulation results using prerecorded neural data from the sea-slug (Aplysia californica) show that the application of the proposed design approach can lead to significant improvement in total energy, without compromising the output signal quality under process variations, compared to conventional design approaches.
A new axial smoothing method based on elastic mapping
NASA Astrophysics Data System (ADS)
Yang, J.; Huang, S. C.; Lin, K. P.; Czernin, J.; Wolfenden, P.; Dahlbom, M.; Hoh, C. K.; Phelps, M. E.
1996-12-01
New positron emission tomography (PET) scanners have higher axial and in-plane spatial resolutions but at the expense of reduced per plane sensitivity, which prevents the higher resolution from being fully realized. Normally, Gaussian-weighted interplane axial smoothing is used to reduce noise. In this study, the authors developed a new algorithm that first elastically maps adjacent planes, and then the mapped images are smoothed axially to reduce the image noise level. Compared to those obtained by the conventional axial-directional smoothing method, the images by the new method have improved signal-to-noise ratio. To quantify the signal-to-noise improvement, both simulated and real cardiac PET images were studied. Various Hanning reconstruction filters with cutoff frequency=0.5, 0.7, 1.0/spl times/Nyquist frequency and Ramp filter were tested on simulated images. Effective in-plane resolution was measured by the effective global Gaussian resolution (EGGR) and noise reduction was evaluated by the cross-correlation coefficient. Results showed that the new method was robust to various noise levels and indicated larger noise reduction or better image feature preservation (i.e., smaller EGGR) than by the conventional method.
Papes, Sandra; Ladich, Friedrich
2011-01-01
Background Sound production and hearing sensitivity of ectothermic animals are affected by the ambient temperature. This is the first study investigating the influence of temperature on both sound production and on hearing abilities in a fish species, namely the neotropical Striped Raphael catfish Platydoras armatulus. Methodology/Principal Findings Doradid catfishes produce stridulation sounds by rubbing the pectoral spines in the shoulder girdle and drumming sounds by an elastic spring mechanism which vibrates the swimbladder. Eight fish were acclimated for at least three weeks to 22°, then to 30° and again to 22°C. Sounds were recorded in distress situations when fish were hand-held. The stridulation sounds became shorter at the higher temperature, whereas pulse number, maximum pulse period and sound pressure level did not change with temperature. The dominant frequency increased when the temperature was raised to 30°C and the minimum pulse period became longer when the temperature decreased again. The fundamental frequency of drumming sounds increased at the higher temperature. Using the auditory evoked potential (AEP) recording technique, the hearing thresholds were tested at six different frequencies from 0.1 to 4 kHz. The temporal resolution was determined by analyzing the minimum resolvable click period (0.3–5 ms). The hearing sensitivity was higher at the higher temperature and differences were more pronounced at higher frequencies. In general, latencies of AEPs in response to single clicks became shorter at the higher temperature, whereas temporal resolution in response to double-clicks did not change. Conclusions/Significance These data indicate that sound characteristics as well as hearing abilities are affected by temperatures in fishes. Constraints imposed on hearing sensitivity at different temperatures cannot be compensated even by longer acclimation periods. These changes in sound production and detection suggest that acoustic orientation and communication are affected by temperature changes in the neotropical catfish P. armatulus. PMID:22022618
NASA Astrophysics Data System (ADS)
Browning, David
2011-04-01
The greatest ocean pH change, which will result in lower low frequency sound attenuation, is predicted for higher latitudes. Here shallow sound channel axies exist, allowing the impact on sound to be seen sooner and also more extensively since the principal propagation paths will be near the surface. However, at the same time, higher wind speeds and greater ice breakup,as well as increased ship traffic, could result in higher noise levels. Marine mammals in this environment may have, on one hand, improving communication conditions but also the possibility of increased background noise.
Thermal-noise-limited higher-order mode locking of a reference cavity.
Zeng, X Y; Ye, Y X; Shi, X H; Wang, Z Y; Deng, K; Zhang, J; Lu, Z H
2018-04-15
Higher-order mode locking has been proposed to reduce the thermal noise limit of reference cavities. By locking a laser to the HG 02 mode of a 10-cm long all ultra-low expansion (ULE) cavity and measuring its performance with the three-cornered-hat method among three independently stabilized lasers, we demonstrate a thermal-noise-limited performance of a fractional frequency instability of 4.9×10 -16 . The results match the theoretical models with higher-order optical modes. The achieved laser instability improves the all ULE short cavity results to a new low level.
NASA Astrophysics Data System (ADS)
Zhang, Yixin; Zhang, Xuping; Shi, Yuanlei; Ying, Zhoufeng; Wang, Shun
2014-06-01
Capacitive gate transient noise has been problematic for the high-speed single photon avalanche photodiode (SPAD), especially when the operating frequency extends to the gigahertz level. We proposed an electro-optic modulator based gate transient noise suppression method for sine-wave gated InGaAs/InP SPAD. With the modulator, gate transient is up-converted to its higher-order harmonics that can be easily removed by low pass filtering. The proposed method enables online tuning of the operating rate without modification of the hardware setup. At 250 K, detection efficiency of 14.7% was obtained with 4.8×10-6 per gate dark count and 3.6% after-pulse probabilities for 1550-nm optical signal under 1-GHz gating frequency. Experimental results have shown that the performance of the detector can be maintained within a designated frequency range from 0.97 to 1.03 GHz, which is quite suitable for practical high-speed SPAD applications operated around the gigahertz level.
Ou, Lili; Duan, Xiaolu; Zeng, Guohua
2013-01-01
Objective Epidemiological data reveal that the overall risk for kidney stones disease is lower for women compared to age-matched men. However, the beneficial effect for the female sex is lost upon menopause, a time corresponding to the onset of fall in estrogen levels. The aim of this study was to describe the serum estradiol (E2) and testosterone (T) characteristics of naturally postmenopausal women with kidney stones. Methods 113 naturally postmenopausal women with newly diagnosed kidney stones (aged 57.4±4.98 years) and 84 age frequency matched stone-free controls (56.9±4.56 years) were validly recruited in the case-control study. The odds ratios (ORs) for the associations between sex hormones and kidney stones were estimated with logistic regression models, adjusting for demographic data and medical history. Patients were also stratified analyzed according to stone components (calcium oxalate stones [COS]; non-calcium oxalate stones [NCOS]). Results Serum E2 (21.1 vs. 31.1 pg/ml) was significantly lower in kidney stones patients compared to controls. Post-hoc analysis demonstrated that this effect was driven by COS patients (p<0.001). According to tertiles of the E2 levels, a significant higher frequency of COS was seen in the lowest E2 group (p <0.001). Multiple logistic regression analysis identified E2 level as a strong factor that was independently associated with the risk for COS (per 1 SD increase, OR=0.951, 95% confidence interval [CI] = 0.919-0.985; highest: lowest tertile, OR=0.214, 95%CI = 0.069-0.665). However, serum T levels did not significantly differ among the groups. Conclusions Naturally postmenopausal women with higher remaining estradiol levels appear less likely to suffer from kidney calcium oxalate stones. However, no correlation was found between serum T level and kidney stones. These findings support the hypothesis that higher postmenopausal endogenous estrogens may protect against kidney stones with ageing. PMID:24086550
Zhao, Zhijian; Mai, Zanlin; Ou, Lili; Duan, Xiaolu; Zeng, Guohua
2013-01-01
Epidemiological data reveal that the overall risk for kidney stones disease is lower for women compared to age-matched men. However, the beneficial effect for the female sex is lost upon menopause, a time corresponding to the onset of fall in estrogen levels. The aim of this study was to describe the serum estradiol (E2) and testosterone (T) characteristics of naturally postmenopausal women with kidney stones. 113 naturally postmenopausal women with newly diagnosed kidney stones (aged 57.4±4.98 years) and 84 age frequency matched stone-free controls (56.9±4.56 years) were validly recruited in the case-control study. The odds ratios (ORs) for the associations between sex hormones and kidney stones were estimated with logistic regression models, adjusting for demographic data and medical history. Patients were also stratified analyzed according to stone components (calcium oxalate stones [COS]; non-calcium oxalate stones [NCOS]). Serum E2 (21.1 vs. 31.1 pg/ml) was significantly lower in kidney stones patients compared to controls. Post-hoc analysis demonstrated that this effect was driven by COS patients (p<0.001). According to tertiles of the E2 levels, a significant higher frequency of COS was seen in the lowest E2 group (p <0.001). Multiple logistic regression analysis identified E2 level as a strong factor that was independently associated with the risk for COS (per 1 SD increase, OR=0.951, 95% confidence interval [CI] = 0.919-0.985; highest: lowest tertile, OR=0.214, 95%CI = 0.069-0.665). However, serum T levels did not significantly differ among the groups. Naturally postmenopausal women with higher remaining estradiol levels appear less likely to suffer from kidney calcium oxalate stones. However, no correlation was found between serum T level and kidney stones. These findings support the hypothesis that higher postmenopausal endogenous estrogens may protect against kidney stones with ageing.
Lin, Heng-Teng; Chiu, Chong-Chi; Wang, Jhi-Joung; Hung, Ching-Hsia; Chen, Yu-Wen
2015-03-04
The impact of coadministration of transcutaneous electrical nerve stimulation (TENS) and diphenidol is not well established. Here we estimated the effects of diphenidol in combination with TENS on mechanical allodynia and tumor necrosis factor-α (TNF-α) expression. Using an animal chronic constriction injury (CCI) model, the rat was estimated for evidence of mechanical sensitivity via von Frey hair stimulation and TNF-α expression in the sciatic nerve using the ELISA assay. High frequency (100Hz) TENS or intraperitoneal injection of diphenidol (2.0μmol/kg) was applied daily, starting on postoperative day 1 (POD1) and lasting for the next 13 days. We demonstrated that both high frequency TENS and diphenidol groups had an increase in mechanical withdrawal thresholds of 60%. Coadministration of high frequency TENS and diphenidol gives better results of paw withdrawal thresholds in comparison with high frequency TENS alone or diphenidol alone. Both diphenidol and coadministration of high frequency TENS with diphenidol groups showed a significant reduction of the TNF-α level compared with the CCI or HFS group (P<0.05) in the sciatic nerve on POD7, whereas the CCI or high frequency TENS group exhibited a higher TNF-α level than the sham group (P<0.05). Our resulting data revealed that diphenidol alone, high frequency TENS alone, and the combination produced a reduction of neuropathic allodynia. Both diphenidol and the combination of diphenidol with high frequency TENS inhibited TNF-α expression. A moderately effective dose of diphenidol appeared to have an additive effect with high frequency TENS. Therefore, multidisciplinary treatments could be considered for this kind of mechanical allodynia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Riley, Andrew R; Grennan, Allison; Menousek, Kathryn; Hoffses, Kathryn W
2018-03-01
Integration of psychological services into pediatric primary care is increasingly common, but models of integration vary with regard to their level of coordination, colocation, and integration. High-integration models may provide some distinct advantages, such as preventative care and brief consultation for subclinical behavior concerns; however, psychologists face barriers to seeking reimbursement for these services. Alternatives to traditional psychotherapy and psychological testing codes, specifically Health & Behavior (H&B) codes, have been proposed as 1 method for supporting integrated care. The aim of this study was to investigate the relationships between psychologists' reported billing practices, reimbursement rates, and model of integration in pediatric primary care. As part of a larger survey study, 55 psychologists working in pediatric primary care reported on characteristics of their practice's model of integration, billing practices, and frequency of reimbursement for consultative services. Compared with those who categorized their integrated care model as colocated, psychologists who endorsed working in integrated models reported a significantly higher usage of H&B codes and more frequent reimbursement for consultations. Overall, use of H&B codes was associated with higher reported levels of coordination and integration. Survey results showed a clear pattern of higher integration being associated with greater utilization of H&B codes and better reimbursement for consultation activities. These results underscore the importance of establishing and maintaining billing and reimbursement systems that adequately support integrated care. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Role of Depression, Anxiety and Stress in Patients with Oral Lichen Planus: A Pilot Study
Kalkur, Chaithra; Sattur, Atul Prahlad; Guttal, Kruthika Satyabodh
2015-01-01
Context: Lichen planus is a psychosomatic disease. Higher frequency of psychiatric symptoms, poor quality of life, higher level of anxiety and neuroendocrine and immune dysregulations, all these factors, will enhance the exacerbation of the disease. Aims: The present study was to assess depression, anxiety and stress levels in patients with oral lichen planus. Materials and Methods: The psychometric evaluation using the Depression Anxiety Stress Scale (DASS)-42 questionnaire was carried out, by the same investigator on all members of group 1 (Oral Lichen Planus) and group 2 (Control). DASS-42 questionnaire consists of 42 symptoms divided into three subscales of 14 items: Depression scale, anxiety scale, and stress scale. Statistical Analysis Used: The Student t test was used to determine statistical difference for both the groups and to evaluate for significant relationships among variables. Results: Psychological assessment using DASS-42 reveals lichen planus patients showed higher frequency of psychiatric co morbidities like depression, anxiety and stress compared to control group. Conclusions: This study has provided evidence that the DASS-42 questionnaire is internally consistent and valid measures of depression, anxiety, and stress. Psychiatric evaluation can be considered for patients with oral lichen planus with routine treatment protocols are recommended. DASS-42 Questionnaire can also be used to determine the level of anxiety, stress and depression in diseases of the oral mucosa like recurrent apthous stomatitis, burning mouth syndrome and TMD disorders. PMID:26538689
Shakeri, Mahsa; Zakeri, Farideh; Changizi, Vahid; Rajabpour, Mohammad Reza; Farshidpour, Mohammad Reza
2017-06-15
Industrial radiography is the process of using either gamma-emitting radionuclide sources or X-ray machines to examine the safety of industrial materials. The average annual effective dose in industrial radiography is one of the highest among radiation workers. The aim of this study was to investigate the cytogenetic effects of ionizing radiation in the peripheral blood lymphocytes of 60 industrial radiographers and 40 non-exposed individuals as the control group by using cytokinesis-block micronucleus (CBMN) assay. Totally, the frequencies of micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) were significantly higher in the industrial radiographers than in the controls (p = 0.000). The mean MN frequency per 1000 binucleated cells in the industrial radiographers with last 5-y radiation dose of >100 mSv was significantly higher than those with ≤100 mSv (34.81 ± 12.7‰ vs. 26.33 ± 7.94‰, p = 0.024). The effect of age was observed in the control group and subjects with the age of >30 y showed significantly higher MN frequency compared with the subjects with the age of ≤30 y (9.45 ± 3.71‰ vs. 6.81 ± 3.05‰, p = 0.02). No obvious trend of increased MN as a function of either duration of employment or age or smoking status was observed in the industrial radiographers. The results show the increased levels of cytogenetic damages in the industrial radiographers. Even the workers exposed to the permissible doses are subjected to elevated frequencies of DNA damages. These findings confirm the importance of cytogenetic biomonitoring program beside physical dosimetry, surveying radiation safety of equipment and periodic training of workers for improvement of safety and radiation protection. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Lexical frequency and acoustic reduction in spoken Dutch
NASA Astrophysics Data System (ADS)
Pluymaekers, Mark; Ernestus, Mirjam; Baayen, R. Harald
2005-10-01
This study investigates the effects of lexical frequency on the durational reduction of morphologically complex words in spoken Dutch. The hypothesis that high-frequency words are more reduced than low-frequency words was tested by comparing the durations of affixes occurring in different carrier words. Four Dutch affixes were investigated, each occurring in a large number of words with different frequencies. The materials came from a large database of face-to-face conversations. For each word containing a target affix, one token was randomly selected for acoustic analysis. Measurements were made of the duration of the affix as a whole and the durations of the individual segments in the affix. For three of the four affixes, a higher frequency of the carrier word led to shorter realizations of the affix as a whole, individual segments in the affix, or both. Other relevant factors were the sex and age of the speaker, segmental context, and speech rate. To accommodate for these findings, models of speech production should allow word frequency to affect the acoustic realizations of lower-level units, such as individual speech sounds occurring in affixes.
Broadband calibration of R/V Ewing seismic sources
NASA Astrophysics Data System (ADS)
Tolstoy, M.; Diebold, J. B.; Webb, S. C.; Bohnenstiehl, D. R.; Chapp, E.; Holmes, R. C.; Rawson, M.
2004-07-01
The effects of anthropogenic sound sources on marine mammals are of increasing interest and controversy [e.g., Malakoff, 2001]. To understand and mitigate better the possible impacts of specific sound sources, well-calibrated broadband measurements of acoustic received levels must be made in a variety of environments. In late spring 2003 an acoustic calibration study was conducted in the northern Gulf of Mexico to obtain broad frequency band measurements of seismic sources used by the R/V Maurice Ewing. Received levels in deep water were lower than anticipated based on modeling, and in shallow water they were higher. For the marine mammals of greatest concern (beaked whales) the 1-20 kHz frequency range is considered particularly significant [National Oceanic Atmospheric Administration and U. S. Navy, 2001; Frantzis et al., 2002]. 1/3-octave measurements show received levels at 1 kHz are ~20-33 dB (re: 1 μPa) lower than peak levels at 5-100 Hz, and decrease an additional ~20-33 dB in the 10-20 kHz range.
Color-motion feature-binding errors are mediated by a higher-order chromatic representation
Shevell, Steven K.; Wang, Wei
2017-01-01
Peripheral and central moving objects of the same color may be perceived to move in the same direction even though peripheral objects have a different true direction of motion [Nature 429, 262 (2004)]. The perceived, illusory direction of peripheral motion is a color-motion feature-binding error. Recent work shows that such binding errors occur even without an exact color match between central and peripheral objects, and, moreover, the frequency of the binding errors in the periphery declines as the chromatic difference increases between the central and peripheral objects [J. Opt. Soc. Am. A 31, A60 (2014)]. This change in the frequency of binding errors with the chromatic difference raises the general question of the chromatic representation from which the difference is determined. Here, basic properties of the chromatic representation are tested to discover whether it depends on independent chromatic differences on the l and the s cardinal axes or, alternatively, on a more specific higher-order chromatic representation. Experimental tests compared the rate of feature-binding errors when the central and peripheral colors had the identical s chromaticity (so zero difference in s) and a fixed magnitude of l difference, while varying the identical s level in center and periphery (thus always keeping the s difference at zero). A chromatic representation based on independent l and s differences would result in the same frequency of color-motion binding errors at every s level. The results are contrary to this prediction, thus showing that the chromatic representation at the level of color-motion feature binding depends on a higherorder chromatic mechanism. PMID:26974945
SRG110 Stirling Generator Dynamic Simulator Vibration Test Results and Analysis Correlation
NASA Technical Reports Server (NTRS)
Suarez, Vicente J.; Lewandowski, Edward J.; Callahan, John
2006-01-01
The U.S. Department of Energy (DOE), Lockheed Martin (LM), and NASA Glenn Research Center (GRC) have been developing the Stirling Radioisotope Generator (SRG110) for use as a power system for space science missions. The launch environment enveloping potential missions results in a random input spectrum that is significantly higher than historical RPS launch levels and is a challenge for designers. Analysis presented in prior work predicted that tailoring the compliance at the generator-spacecraft interface reduced the dynamic response of the system thereby allowing higher launch load input levels and expanding the range of potential generator missions. To confirm analytical predictions, a dynamic simulator representing the generator structure, Stirling convertors and heat sources was designed and built for testing with and without a compliant interface. Finite element analysis was performed to guide the generator simulator and compliant interface design so that test modes and frequencies were representative of the SRG110 generator. This paper presents the dynamic simulator design, the test setup and methodology, test article modes and frequencies and dynamic responses, and post-test analysis results. With the compliant interface, component responses to an input environment exceeding the SRG110 qualification level spectrum were all within design allowables. Post-test analysis included finite element model tuning to match test frequencies and random response analysis using the test input spectrum. Analytical results were in good overall agreement with the test results and confirmed previous predictions that the SRG110 power system may be considered for a broad range of potential missions, including those with demanding launch environments.
SRG110 Stirling Generator Dynamic Simulator Vibration Test Results and Analysis Correlation
NASA Technical Reports Server (NTRS)
Lewandowski, Edward J.; Suarez, Vicente J.; Goodnight, Thomas W.; Callahan, John
2007-01-01
The U.S. Department of Energy (DOE), Lockheed Martin (LM), and NASA Glenn Research Center (GRC) have been developing the Stirling Radioisotope Generator (SRG110) for use as a power system for space science missions. The launch environment enveloping potential missions results in a random input spectrum that is significantly higher than historical radioisotope power system (RPS) launch levels and is a challenge for designers. Analysis presented in prior work predicted that tailoring the compliance at the generator-spacecraft interface reduced the dynamic response of the system thereby allowing higher launch load input levels and expanding the range of potential generator missions. To confirm analytical predictions, a dynamic simulator representing the generator structure, Stirling convertors and heat sources were designed and built for testing with and without a compliant interface. Finite element analysis was performed to guide the generator simulator and compliant interface design so that test modes and frequencies were representative of the SRG110 generator. This paper presents the dynamic simulator design, the test setup and methodology, test article modes and frequencies and dynamic responses, and post-test analysis results. With the compliant interface, component responses to an input environment exceeding the SRG110 qualification level spectrum were all within design allowables. Post-test analysis included finite element model tuning to match test frequencies and random response analysis using the test input spectrum. Analytical results were in good overall agreement with the test results and confirmed previous predictions that the SRG110 power system may be considered for a broad range of potential missions, including those with demanding launch environments.
NASA Astrophysics Data System (ADS)
Potter, Andrea; McCune, Matthew A.; de, Ruma; Madjet, Mohamed E.; Chakraborty, Himadri S.
2010-09-01
Considering the photoionization of the Xe@C60 endohedral compound, we study in detail the ionization cross sections of various levels of the system at energies higher than the plasmon resonance region. Five classes of single-electron levels are identified depending on their spectral character. Each class engenders distinct oscillations in the cross section, emerging from the interference between active ionization modes specific to that class. Analysis of the cross sections based on their Fourier transforms unravels oscillation frequencies that carry unique fingerprints of the emitting level.
Temporal epilepsy seizures monitoring and prediction using cross-correlation and chaos theory.
Haddad, Tahar; Ben-Hamida, Naim; Talbi, Larbi; Lakhssassi, Ahmed; Aouini, Sadok
2014-01-01
Temporal seizures due to hippocampal origins are very common among epileptic patients. Presented is a novel seizure prediction approach employing correlation and chaos theories. The early identification of seizure signature allows for various preventive measures to be undertaken. Electro-encephalography signals are spectrally broken down into the following sub-bands: delta; theta; alpha; beta; and gamma. The proposed approach consists of observing a high correlation level between any pair of electrodes for the lower frequencies and a decrease in the Lyapunov index (chaos or entropy) for the higher frequencies. Power spectral density and statistical analysis tools were used to determine threshold levels for the lower frequencies. After studying all five sub-bands, the analysis has revealed that the seizure signature can be extracted from the delta band and the high frequencies. High frequencies are defined as both the gamma band and the ripples occurring within the 60-120 Hz sub-band. To validate the proposed approach, six patients from both sexes and various age groups with temporal epilepsies originating from the hippocampal area were studied using the Freiburg database. An average seizure prediction of 30 min, an anticipation accuracy of 72%, and a false-positive rate of 0% were accomplished throughout 200 h of recording time.
Beneficial role of D allele in controlling ACE levels: a study among Brahmins of north India.
Kumari, Shobha; Sharma, Nidhi; Thakur, Sunil; Mondal, Prakash R; Saraswathy, Kallur N
2016-06-01
India being a country with vast diversity is expected to have different dietary and life style patterns which in turn may lead to population-specific environmental risk factors. Further, the interaction of these risk factors with the genetic makeup of population makes it either susceptible or resistant to cardiovascular disease. One such candidate gene is angiotensin converting enzyme (ACE) for various cardiovascular mechanisms. ACE is the key enzyme of the renin angiotensin aldosterone system pathway which maintains homeostasis blood pressure in the body and any variation in the levels is reported to be associated with various complex diseases. The DD genotype is found to increase ACE levels, which is associated with cardiovascular diseases and decrease in ACE levels are associated with kidney diseases. The aim of this study was to understand the distribution of ACE I/D polymorphism and ACE levels among Brahmins of National Capital Region (NCR) north India, with respect to age and sex ratio distribution. In this study, 136 subjects of which 50 males and 86 females, who were unrelated up to first cousin, aged 25 to70 years were studied. ACE gene was found to be polymorphic with high frequency of heterozygote (ID) followed by II and DD genotypes. The studied population was found to be in Hardy-Weinberg equilibrium with respect to ACE I/D polymorphism (P = 0.55). I allele frequency was found to be higher (0.560) than the D allele (0.44). The median level of ACE was found to be 65.96 ng/mL (48.12-86.24) which is towards lower side of the normal range. ACE levels were found to be increased among individual having either of the homozygotes that is II or DD and higher frequency of heterozygote (ID) is indicative of advantage in the population by maintaining lower ACE levels. The limitation of the present study is low sample size, however, the merit is that the subjects belonged to a Mendalian population with a common gene pool.
The impact of frequency on the performance of microwave ablation.
Sawicki, James F; Shea, Jacob D; Behdad, Nader; Hagness, Susan C
2017-02-01
The use of higher frequencies in percutaneous microwave ablation (MWA) may offer compelling interstitial antenna design advantages over the 915 MHz and 2.45 GHz frequencies typically employed in current systems. To evaluate the impact of higher frequencies on ablation performance, we conducted a comprehensive computational and experimental study of microwave absorption and tissue heating as a function of frequency. We performed electromagnetic and thermal simulations of MWA in ex vivo and in vivo porcine muscle at discrete frequencies in the 1.9-26 GHz range. Ex vivo ablation experiments were performed in the 1.9-18 GHz range. We tracked the size of the ablation zone across frequency for constant input power and ablation duration. Further, we conducted simulations to investigate antenna feed line heating as a function of frequency, input power, and cable diameter. As the frequency was increased from 1.9 to 26 GHz the resulting ablation zone dimensions decreased in the longitudinal direction while remaining relatively constant in the radial direction; thus at higher frequencies the overall ablation zone was more spherical. However, cable heating at higher frequencies became more problematic for smaller diameter cables at constant input power. Comparably sized ablation zones are achievable well above 1.9 GHz, despite increasingly localised power absorption. Specific absorption rate alone does not accurately predict ablation performance, particularly at higher frequencies where thermal diffusion plays an important role. Cable heating due to ohmic losses at higher frequencies may be controlled through judicious choices of input power and cable diameter.
Relation of Secondhand Smoking to Mild Cognitive Impairment in Older Inpatients
Orsitto, Giuseppe; Turi, Vincenzo; Venezia, Amedeo; Fulvio, Francesco; Manca, Cosimo
2012-01-01
Up to now, controversy still exists regarding the role of secondhand smoking (SHS) in developing cognitive impairment. This study aimed to evaluate the prevalence of SHS in hospitalized older patients with cognitive deficit, particularly in those with mild cognitive impairment (MCI). Smoking history was classified into four groups: never smokers, former-active smokers/no SHS, active smokers, and secondhand smokers, and cognitive function into three levels: normal cognition (C), MCI, and dementia. A total of 933 older subjects with diagnoses of MCI (n = 98), dementia (n = 124), or C (n = 711) were enrolled in this cross-sectional study. As expected, patients with dementia had significantly higher frequency of former-active smokers than cognitively normal. Moreover, patients with MCI showed a significantly higher frequency of active and secondhand smokers than patients with dementia or C. A smoking history is very frequent in older patients with dementia. Patients with MCI had even higher rate of exposure to active or secondhand smoking. PMID:22666146
Matsui, Teppei; Ohki, Kenichi
2013-01-01
Higher order visual areas that receive input from the primary visual cortex (V1) are specialized for the processing of distinct features of visual information. However, it is still incompletely understood how this functional specialization is acquired. Here we used in vivo two photon calcium imaging in the mouse visual cortex to investigate whether this functional distinction exists at as early as the level of projections from V1 to two higher order visual areas, AL and LM. Specifically, we examined whether sharpness of orientation and direction selectivity and optimal spatial and temporal frequency of projection neurons from V1 to higher order visual areas match with that of target areas. We found that the V1 input to higher order visual areas were indeed functionally distinct: AL preferentially received inputs from V1 that were more orientation and direction selective and tuned for lower spatial frequency compared to projection of V1 to LM, consistent with functional differences between AL and LM. The present findings suggest that selective projections from V1 to higher order visual areas initiates parallel processing of sensory information in the visual cortical network. PMID:24068987
Noise-induced hearing loss in workers exposed to urban stressors.
Caciari, Tiziana; Rosati, Maria Valeria; Casale, Teodorico; Loreti, Beatrice; Sancini, Angela; Riservato, Roberto; Nieto, Hector A; Frati, Paola; Tomei, Francesco; Tomei, Gianfranco
2013-10-01
The technological and industrial progress together with the intensification of vehicular traffic and the adoption of new social habits are the cause of an increasing noise pollution with possible negative effects on the auditory system. This study aims to assess the noise exposure levels and the effects on the hearing threshold in outdoor and indoor male workers of a big Italian city. The study was carried out on 357 outdoor male workers, exposed to urban noise and on a control group of 357 unexposed indoor workers. Noise levels were measured in 30 outdoor and indoor areas. The subjects underwent tonal liminal audiometry in order to determine the value of their hearing threshold. During their working activity, outdoor and indoor workers are exposed to different noise levels LEX<80 dB(A). At mid-low frequencies (250-2000 Hz), the results show significant differences in the average values of hearing threshold between the two groups in both ears and for all age classes; there are no significant differences between the two groups at higher frequencies. The outdoor noise levels measured are not usually ototoxic and the hearing loss at mid-low frequencies is not characteristic of the exposure to industrial noise. For these reasons the Authors hypothesize that the results may be due to the combined effect of the exposure to noise and to ototoxic air pollutants. The impairment of speech frequencies is disabling and involves the risk of missed forensic recognition. Copyright © 2013 Elsevier B.V. All rights reserved.
Tzamaloukas, Antonios H; Ing, Todd S; Elisaf, Moses S; Raj, Dominic S C; Siamopoulos, Kostas C; Rohrscheib, Mark; Murata, Glen H
2011-06-01
The main difference between dialysis-associated hyperglycemia (DH) and diabetic ketoacidosis (DKA) or nonketotic hyperglycemia (NKH) occurring in patients with preserved renal function is the absence of osmotic diuresis in DH, which eliminates the need for large fluid and solute (including potassium) replacement. We analyzed published reports of serum potassium (K(+)) abnormalities and their treatment in DH. Hyperkalemia was often present at presentation of DH with higher frequency and severity than in hyperglycemic syndromes in patients with preserved renal function. The frequency and severity of hyperkalemia were higher in DH episodes with DKA than those with NKH in both hemodialysis and peritoneal dialysis. For DKA, the frequency and severity of hyperkalemia were similar in hemodialysis and peritoneal dialysis. For NKH, hyperkalemia was more severe and frequent in hemodialysis than in peritoneal dialysis. Insulin infusion corrected the hyperkalemia of DH in most cases. Additional measures for the management of hyperkalemia or modest potassium infusions for hypokalemia were needed in a few DH episodes. The predictors of the decrease in serum K(+) during treatment of DH with insulin included the starting serum K(+) level, the decreases in serum values of glucose concentration and tonicity, and the increase in serum total carbon dioxide level. DH represents a risk factor for hyperkalemia. Insulin infusion is the only treatment for hyperkalemia usually required.
Effects of experimentally measured pressure oscillations on the vibration of a solid rocket motor
NASA Technical Reports Server (NTRS)
Schoenster, J. A.; Pierce, H. B.
1972-01-01
Results are presented of firing a Nike rocket against a backstop for the purpose of obtaining pressure fluctuations in the rocket case and determining their relationship to structural vibrations of the case. Special care was required to obtain these pressure fluctuations because of the much higher static pressure generated in the rocket. Very small pressure fluctuations within the rocket case can cause significant vibration levels. A previously observed high frequency was shown to decrease with time before completely disappearing at about 1 second of burning time. The vibration of the case itself is probably related to the longitudinal structural modes at frequencies below 500 Hz and is dependent on local structural conditions at frequencies above this value.
Collaboration on Development and Validation of the AMSR-E Snow Water Equivalent Algorithm
NASA Technical Reports Server (NTRS)
Armstrong, Richard L.
2000-01-01
The National Snow and Ice Data Center (NSIDC) has produced a global SMMR and SSM/I Level 3 Brightness Temperature data set in the Equal Area Scalable Earth (EASE) Grid for the period 1978 to 2000. Processing of current data is-ongoing. The EASE-Grid passive microwave data sets are appropriate for algorithm development and validation prior to the launch of AMSR-E. Having the lower frequency channels of SMMR (6.6 and 10.7 GHz) and the higher frequency channels of SSM/I (85.5 GHz) in the same format will facilitate the preliminary development of applications which could potentially make use of similar frequencies from AMSR-E (6.9, 10.7, 89.0 GHz).
On the viewing angle dependence of blazar variability
NASA Astrophysics Data System (ADS)
Eldar, Avigdor; Levinson, Amir
2000-05-01
Internal shocks propagating through an ambient radiation field are subject to a radiative drag that, under certain conditions, can significantly affect their dynamics, and consequently the evolution of the beaming cone of emission produced behind the shocks. The resultant change of the Doppler factor combined with opacity effects leads to a strong dependence on the viewing angle of the variability pattern produced by such systems; specifically, the shape of the light curves and the characteristics of correlated emission. One implication is that objects oriented at relatively large viewing angles to the observer should exhibit a higher level of activity at high synchrotron frequencies (above the self-absorption frequency), and also at gamma-ray energies below the threshold energy of pair production, than at lower (radio/millimetre) frequencies.
Joint projections of US East Coast sea level and storm surge
NASA Astrophysics Data System (ADS)
Little, Christopher M.; Horton, Radley M.; Kopp, Robert E.; Oppenheimer, Michael; Vecchi, Gabriel A.; Villarini, Gabriele
2015-12-01
Future coastal flood risk will be strongly influenced by sea-level rise (SLR) and changes in the frequency and intensity of tropical cyclones. These two factors are generally considered independently. Here, we assess twenty-first century changes in the coastal hazard for the US East Coast using a flood index (FI) that accounts for changes in flood duration and magnitude driven by SLR and changes in power dissipation index (PDI, an integrated measure of tropical cyclone intensity, frequency and duration). Sea-level rise and PDI are derived from representative concentration pathway (RCP) simulations of 15 atmosphere-ocean general circulation models (AOGCMs). By 2080-2099, projected changes in the FI relative to 1986-2005 are substantial and positively skewed: a 10th-90th percentile range 4-75 times higher for RCP 2.6 and 35-350 times higher for RCP 8.5. High-end FI projections are driven by three AOGCMs that project the largest increases in SLR, PDI and upper ocean temperatures. Changes in PDI are particularly influential if their intra-model correlation with SLR is included, increasing the RCP 8.5 90th percentile FI by a further 25%. Sea-level rise from other, possibly correlated, climate processes (for example, ice sheet and glacier mass changes) will further increase coastal flood risk and should be accounted for in comprehensive assessments.
Joint Projections of US East Coast Sea Level and Storm Surge
NASA Technical Reports Server (NTRS)
Little, Christopher M.; Horton, Radley M.; Kopp, Robert E.; Oppenheimer, Michael; Vecchi, Gabriel A.; Villarini, Gabriele
2015-01-01
Future coastal flood risk will be strongly influenced by sea-level rise (SLR) and changes in the frequency and intensity of tropical cyclones. These two factors are generally considered independently. Here, we assess twenty-first century changes in the coastal hazard for the US East Coast using a flood index (FI) that accounts for changes in flood duration and magnitude driven by SLR and changes in power dissipation index (PDI, an integrated measure of tropical cyclone intensity, frequency and duration). Sea-level rise and PDI are derived from representative concentration pathway (RCP) simulations of 15 atmosphere- ocean general circulation models (AOGCMs). By 2080-2099, projected changes in the FI relative to 1986-2005 are substantial and positively skewed: a 10th-90th percentile range 4-75 times higher for RCP 2.6 and 35-350 times higher for RCP 8.5. High-end Fl projections are driven by three AOGCMs that project the largest increases in SLR, PDI and upper ocean temperatures. Changes in PDI are particularly influential if their intra-model correlation with SLR is included, increasing the RCP 8.5 90th percentile FI by a further 25%. Sea-level rise from other, possibly correlated, climate processes (for example, ice sheet and glacier mass changes) will further increase coastal flood risk and should be accounted for in comprehensive assessments.
Effect of tractor driving on hearing loss in farmers in India.
Kumar, Adarsh; Mathur, N N; Varghese, Mathew; Mohan, Dinesh; Singh, J K; Mahajan, Punnet
2005-04-01
Indian tractor drivers operate their tractors and other implements/equipment in an environment which can have extreme temperatures and high level of suspended particulate matter. In addition, Indian tractors do not have adequate vibration and noise attenuating designs features. This cross-sectional study compares the hearing status of tractor driving farmers (TDFs) (study group) and non-tractor driving farmers (NTDFs) (control group) matched for age, sex, generic/ethnic group, land holding, education levels, and work routines. Two groups of 50 experienced tractor-driving farmers and 50 non-driving farmers were selected from 2 villages, 50 km from Delhi. All participants were interviewed for details of work routine and noise exposures. An audiogram was performed and noise measurements taken on tractors and other machines. Self-reported hearing problems were similar (4 cases each) in both the groups of 50 farmers. However, audiogram analysis showed higher prevalence of abnormalities in TDFs. TDFs (24) had more often high frequency hearing loss when compared to NTDFs (14). The noise levels observed on tractors in different operations were in the range of 90-110 dB (A). Tractor noise levels exceeded the recommended safe limits of OSHA and NIOSH prescribed standards. TDFs had higher high frequency hearing loss than NTDFs. The mechanism of damage and prevention needs to be studied further. Copyright (c) 2005 Wiley-Liss, Inc.
NASA Astrophysics Data System (ADS)
Császár, Attila G.; Furtenbacher, T.; Tennyson, Jonathan; Bernath, Peter F.; Brown, Linda R.; Campargue, Alain; Daumont, Ludovic; Gamache, Robert R.; Hodges, Joseph T.; Naumenko, Olga V.; Polyansky, Oleg L.; Rothman, Laurence S.; Vandaele, Ann Carine; Zobov, Nikolai F.
2014-06-01
The results of an IUPAC Task Group formed in 2004 on "A Database of Water Transitions from Experiment and Theory" (Project No. 2004-035-1-100) are presented. Energy levels and recommended labels involving exact and approximate quantum numbers for the main isotopologues of water in the gas phase, H216O, H218O, H217O, HD16O, HD18O, HD17O, D216O, D218O, and D217O, are determined from measured transition wavenumbers. The transition wavenumbers and energy levels are validated using the MARVEL (measured active rotational-vibrational energy levels) approach and first-principles nuclear motion computations. The extensive data, e.g., more than 200,000 transitions have been handled for H216O, including lines and levels that are required for analysis and synthesis of spectra, thermochemical applications, the construction of theoretical models, and the removal of spectral contamination by ubiquitous water lines. These datasets can also be used to assess where measurements are lacking for each isotopologue and to provide accurate frequencies for many yet-to-be measured transitions. The lack of high-quality frequency calibration standards in the near infrared is identified as an issue that has hindered the determination of high-accuracy energy levels at higher frequencies. The generation of spectra using the MARVEL energy levels combined with transition intensities computed using high accuracy ab initio dipole moment surfaces are discussed.
Moore, Brian C J; Ernst, Stephan M A
2012-09-01
It is commonly believed that difference limens for frequency (DLFs) for pure tones depend on a temporal mechanism (phase locking) for frequencies up to 4-5 kHz and a place mechanism at higher frequencies. The DLFs predicted from a place mechanism, expressed as a proportion of center frequency (Δf/f), should be approximately invariant with frequency at medium to high frequencies. If there is a transition from a temporal to a place mechanism, Δf/f should increase with increasing center frequency until the transition occurs, and then reach a plateau. Published data do not show such an effect. In this study, DLFs were measured for center frequencies from 2 to 14 kHz, using earphones designed to produce a flat response at the eardrum. The level of every tone was varied over a range of ±4 dB, to reduce loudness cues. The value of Δf/f increased progressively from 2 to 8 kHz, but did not change significantly for frequencies from 8 to 14 kHz. The results are consistent with the idea that there is a transition from a temporal to a place mechanism at about 8 kHz, rather than at 4-5 kHz, as is commonly assumed.
Kay, S; Caesar, J; Wolf, J; Bricheno, L; Nicholls, R J; Saiful Islam, A K M; Haque, A; Pardaens, A; Lowe, J A
2015-07-01
Coastal flooding due to storm surge and high tides is a serious risk for inhabitants of the Ganges-Brahmaputra-Meghna (GBM) delta, as much of the land is close to sea level. Climate change could lead to large areas of land being subject to increased flooding, salinization and ultimate abandonment in West Bengal, India, and Bangladesh. IPCC 5th assessment modelling of sea level rise and estimates of subsidence rates from the EU IMPACT2C project suggest that sea level in the GBM delta region may rise by 0.63 to 0.88 m by 2090, with some studies suggesting this could be up to 0.5 m higher if potential substantial melting of the West Antarctic ice sheet is included. These sea level rise scenarios lead to increased frequency of high water coastal events. Any effect of climate change on the frequency and severity of storms can also have an effect on extreme sea levels. A shelf-sea model of the Bay of Bengal has been used to investigate how the combined effect of sea level rise and changes in other environmental conditions under climate change may alter the frequency of extreme sea level events for the period 1971 to 2099. The model was forced using atmospheric and oceanic boundary conditions derived from climate model projections and the future scenario increase in sea level was applied at its ocean boundary. The model results show an increased likelihood of extreme sea level events through the 21st century, with the frequency of events increasing greatly in the second half of the century: water levels that occurred at decadal time intervals under present-day model conditions occurred in most years by the middle of the 21st century and 3-15 times per year by 2100. The heights of the most extreme events tend to increase more in the first half of the century than the second. The modelled scenarios provide a case study of how sea level rise and other effects of climate change may combine to produce a greatly increased threat to life and property in the GBM delta by the end of this century.
Wang, Yao; Gong, Qin; Zhang, Tao
2016-05-10
Frequency selectivity (FS) of the auditory system is established at the level of the cochlea and it is important for the perception of complex sounds. Although direct measurements of cochlear FS require surgical preparation, it can also be estimated with the measurements of otoacoustic emissions or behavioral tests, including stimulus frequency otoacoustic emission suppression tuning curves (SFOAE STCs) or psychophysical tuning curves (PTCs). These two methods result in similar estimates of FS at low probe levels. As the compressive nonlinearity of cochlea is strongly dependent on the stimulus intensity, the sharpness of tuning curves which is relevant to the cochlear nonlinearity will change as a function of probe level. The present study aims to investigate the influence of different probe levels on the relationship between SFOAE STCs and PTCs. The study included 15 young subjects with normal hearing. SFOAE STCs and PTCs were recorded at low and moderate probe levels for frequencies centred at 1, 2, and 4 kHz. The ratio or the difference of the characteristic parameters between the two methods was calculated at each probe level. The effect of probe level on the ratio or the difference between the parameters of SFOAE STCs and PTCs was then statistically analysed. The tuning of SFOAE STCs was significantly positively correlated with the tuning of the PTCs at both low and moderate probe levels; yet, at the moderate probe level, the SFOAE STCs were consistently broader than the PTCs. The mean ratio of sharpness of tuning at low probe levels was constantly around 1 while around 1.5 at moderate probe levels. Probe level had a significant effect on the sharpness of tuning between the two methods of estimating FS. SFOAE STC seems a good alternative measurement of PTC for FS assessment at low probe levels. At moderate probe levels, SFOAE STC and PTC were not equivalent measures of the FS in terms of their bandwidths. Because SFOAE STCs are not biased by higher levels auditory processing, they may represent cochlear FS better than PTCs.
Increased Jet Noise Due to a "Nominally Laminar" State of Nozzle Exit Boundary Layer
NASA Technical Reports Server (NTRS)
Zaman, K. B. M. Q.
2017-01-01
A set of 2-in. diameter nozzles is used to investigate the effect of varying exit boundary layer state on the radiated noise from high-subsonic jets. It is confirmed that nozzles involving turbulent boundary layers are the quietest while nozzles involving a "nominally laminar" boundary layer are loud especially on the high-frequency side of the sound pressure level spectrum. The latter boundary layer state involves a "Blasius-like" mean velocity profile but higher turbulence intensities compared to those in the turbulent state. The higher turbulence in the initial region of the jet shear layer leads to increased high-frequency noise. The results strongly suggest that an anomaly noted with subsonic jet noise databases in the literature is due to a similar effect of differences in the initial boundary layer state.
Increased Jet Noise Due to a "Nominally Laminar" State of Nozzle Exit Boundary Layer
NASA Technical Reports Server (NTRS)
Zaman, K. B. M. Q.
2017-01-01
A set of 2-inch diameter nozzles is used to investigate the effect of varying exit boundary layer state on the radiated noise from high-subsonic jets. It is confirmed that nozzles involving turbulent boundary layers are the quietest while nozzles involving a nominally-laminar boundary layer are loud especially on the high-frequency side of the sound pressure level spectrum. The latter boundary layer state involves a Blasius-like mean velocity profile but higher turbulence intensities compared to those in the turbulent state. The higher turbulence in the initial region of the jet shear layer leads to increased high-frequency noise. The results strongly suggest that an anomaly noted with subsonic jet noise databases in the literature is due to a similar effect of differences in the initial boundary layer state.
Is There a Neighborhood Frequency Effect in English?: Evidence from Reading and Lexical Decision
ERIC Educational Resources Information Center
Sears, Christopher R.; Campbell, Crystal R.; Lupker, Stephen J.
2006-01-01
What is the effect of a word's higher frequency neighbors on its identification time? According to activation-based models of word identification (J. Grainger & A. M. Jacobs, 1996; J. L. McClelland & D. E. Rumelhart, 1981), words with higher frequency neighbors will be processed more slowly than words without higher frequency neighbors because of…
Hasanzadeh, Hadi; Mokhtari-Dizaji, Manijhe; Bathaie, S Zahra; Hassan, Zuhair M
2013-10-01
The goal of this study was to localize drug release from nanomicelles using dual-frequency sonication at low levels of acoustic intensity. In this study, the antitumor effect of simultaneous dual-frequency sonication (28 kHz and 3 MHz) at low levels of acoustic intensity in combination with doxorubicin and micellar doxorubicin injection was assessed in a spontaneous model of breast adenocarcinoma in female Balb/c mice. Sixty-three tumor-bearing mice were randomly grouped into control, sham, dual-frequency sonication, doxorubicin injection with and without dual-frequency sonication, and micellar doxorubicin injection with and without dual-frequency sonication groups. The results of volume change relative to initial volume showed that in the micellar doxorubicin injection with sonication group, this parameter was significantly different from that of the control, sham, sonication, and doxorubicin injection groups (P < 0.05). In addition, the volume began to increase on the 15th day after the start of treatment, which is a good indication to repeat treatment; therefore, another group received an extra treatment on day 15. The animal life span in the micellar doxorubicin with sonication and repeated treatment groups was significantly higher than that in all the other experimental groups except for the micellar doxorubicin injection group (P < 0.05). It was concluded that dual-frequency sonication with micellar doxorubicin injection extends the life span relative to doxorubicin injection or dual-frequency sonication alone, and that repeating this treatment on day 15 decreases the rate of tumor growth significantly.
Morais, Jorge E; Garrido, Nuno D; Marques, Mário C; Silva, António J; Marinho, Daniel A; Barbosa, Tiago M
2013-12-18
(i) gender; (ii) performance and; (iii) gender versus performance interactions in young swimmers' anthropometric, kinematic and energetic variables. One hundred and thirty six young swimmers (62 boys: 12.76 ± 0.72 years old at Tanner stages 1-2 by self-evaluation; and 64 girls: 11.89 ± 0.93 years old at Tanner stages 1-2 by self-evaluation) were evaluated. Performance, anthropometrics, kinematics and energetic variables were selected. There was a non-significant gender effect on performance, body mass, height, arm span, trunk transverse surface area, stroke length, speed fluctuation, swimming velocity, propulsive efficiency, stroke index and critical velocity. A significant gender effect was found for foot surface area, hand surface area and stroke frequency. A significant sports level effect was verified for all variables, except for stroke frequency, speed fluctuation and propulsive efficiency. Overall, swimmers in quartile 1 (the ones with highest sports level) had higher anthropometric dimensions, better stroke mechanics and energetics. These traits decrease consistently throughout following quartiles up to the fourth one (i.e. swimmers with the lowest sports level). There was a non-significant interaction between gender and sports level for all variables. Our main conclusions were as follows: (i) there are non-significant differences in performance, anthropometrics, kinematics and energetics between boys and girls; (ii) swimmers with best performance are taller, have higher surface areas and better stroke mechanics; (iii) there are non-significant interactions between sports level and gender for anthropometrics, kinematics and energetics.
Kim, Yeonsoo; Yang, Hye Young; Kim, Ae-Jung; Lim, Yunsook
2013-01-01
The objectives of the present study were to identify the association among levels of persistent academic stress, appetite, and dietary habits and to determine the specific types of sweet foods consumed by Korean high-school students according to their academic stress levels. The study participants included 333 high-school students in the 10th to 12th grades in Kyunggi Province, Korea. The level of academic stress was scored with a 75-item academic stress scale and was categorized as high, medium, or low. A food-frequency questionnaire was used to measure the sugar intake from sweet foods. Korean high-school students with a high academic stress level had larger meals than the other students. Compared with students with low academic stress, the students with high academic stress had a higher frequency of sugar intake from the following food types: confectionaries, candies and chocolates, breads, and flavored milk. Moreover, compared with students with low academic stress, the students with high academic stress had a higher total intake of sugar from the following food types: confectionaries, candies, chocolates, flavored milk, traditional Korean beverages, and spicy, sweet, and fried rice cakes. Unhealthy stress-related food choices may compromise high-school students' health and contribute to their morbidity. The findings of the present study could be used to help nutritionists develop effective strategies for nutritional education and counseling to improve adolescent health. Copyright © 2013 Elsevier Inc. All rights reserved.
Analysis of serum chemokine levels in patients with HIV-associated eosinophilic folliculitis.
Yokobayashi, H; Sugaya, M; Miyagaki, T; Kai, H; Suga, H; Yamada, D; Minatani, Y; Watanabe, K; Kikuchi, Y; Tamaki, T; Sato, S
2013-02-01
Patients with human immunodeficiency virus (HIV) infection exhibit various skin diseases. HIV-associated eosinophilic folliculitis (EF) and pruritic papular eruption (PPE) are frequently seen. To understand the mechanisms underlying HIV-associated EF and PPE. In order to know frequencies of EF and PPE among patients with HIV infection, we first collected HIV(+) patients who visited dermatology clinic in National Center for Global Health and Medicine during February 2007. We next collected 25 serum samples from HIV(+) patients with skin diseases from May 2008 to May 2010. Eight of 25 patients had EF (EF group), four had PPE (PPE group) and others had non-itchy skin problems such as condyloma acuminatum (no itch group). We first confirmed high frequencies of EF (10.7%) and PPE (5.3%) among 75 HIV(+) patients who visited our clinic during one month. We then measured serum levels of CCL11, CCL17, CCL26 and CCL27. Serum CCL17 levels in EF were significantly higher than those of PPE and no itch group. Serum CCL26 and CCL27 levels in EF were higher than those of no itch group. The number of CD4(+) cells in EF was significantly lower than that in no itch group. High serum levels of CCL17, CCL26 and CCL27, and low CD4(+) cell counts may account for the development of HIV-associated EF. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.
Macro-level gender equality and alcohol consumption: a multi-level analysis across U.S. States.
Roberts, Sarah C M
2012-07-01
Higher levels of women's alcohol consumption have long been attributed to increases in gender equality. However, only limited research examines the relationship between gender equality and alcohol consumption. This study examined associations between five measures of state-level gender equality and five alcohol consumption measures in the United States. Survey data regarding men's and women's alcohol consumption from the 2005 Behavioral Risk Factor Surveillance System were linked to state-level indicators of gender equality. Gender equality indicators included state-level women's socioeconomic status, gender equality in socioeconomic status, reproductive rights, policies relating to violence against women, and women's political participation. Alcohol consumption measures included past 30-day drinker status, drinking frequency, binge drinking, volume, and risky drinking. Other than drinker status, consumption is measured for drinkers only. Multi-level linear and logistic regression models adjusted for individual demographics as well as state-level income inequality, median income, and % Evangelical Protestant/Mormon. All gender equality indicators were positively associated with both women's and men's drinker status in models adjusting only for individual-level covariates; associations were not significant in models adjusting for other state-level characteristics. All other associations between gender equality and alcohol consumption were either negative or non-significant for both women and men in models adjusting for other state-level factors. Findings do not support the hypothesis that higher levels of gender equality are associated with higher levels of alcohol consumption by women or by men. In fact, most significant findings suggest that higher levels of equality are associated with less alcohol consumption overall. Copyright © 2012 Elsevier Ltd. All rights reserved.
Rheological properties of ice cream mixes and frozen ice creams containing fat and fat replacers.
Adapa, S; Dingeldein, H; Schmidt, K A; Herald, T J
2000-10-01
Ice cream mixes and frozen ice creams at milk fat levels of 12%, 8%, 6%, 6% plus a protein-based fat replacer, and 6% plus a carbohydrate-based fat replacer were evaluated for viscoelastic properties by dynamic testing with sinusoidal oscillatory tests at various frequencies. The storage modulus (G'), loss modulus (G"), and tan delta (G"/G') were calculated for all the treatments to determine changes in the viscous and elastic properties of the mixes and frozen ice creams due to fat content. In ice cream mixes, G' and G" exhibited a strong frequency dependence. The G" was higher than G' throughout the frequency range (1 to 8 Hz) examined, without any crossover, except for the 12% mix. Elastic properties of the ice cream mixes decreased as fat content decreased. Tan delta values indicated that fat replacers did not enhance the elastic properties of the ice cream mixes. In all frozen ice creams, G' and G" again showed a frequency dependence throughout the range tested (0.5 to 10 Hz). The amount of fat in ice creams and the degree of fat destabilization affected the elasticity in the frozen product. Even though the ice creams did not have significant elastic properties, when compared as a group the samples with higher fat content had higher elastic properties. The addition of protein-based and carbohydrate-based fat replacers did not enhance the elastic properties of the ice creams but did increase the viscous properties.
Dawson, T J; Munn, A J; Blaney, C E; Krockenberger, A; Maloney, S K
2000-01-01
We studied ventilation in kangaroos from mesic and arid environments, the eastern grey kangaroo (Macropus giganteus) and the red kangaroo (Macropus rufus), respectively, within the range of ambient temperatures (T(a)) from -5 degrees to 45 degrees C. At thermoneutral temperatures (Ta=25 degrees C), there were no differences between the species in respiratory frequency, tidal volume, total ventilation, or oxygen extraction. The ventilatory patterns of the kangaroos were markedly different from those predicted from the allometric equation derived for placentals. The kangaroos had low respiratory frequencies and higher tidal volumes, even when adjustment was made for their lower basal metabolism. At Ta>25 degrees C, ventilation was increased in the kangaroos to facilitate respiratory water loss, with percent oxygen extraction being markedly lowered. Ventilation was via the nares; the mouth was closed. Differences in ventilation between the two species occurred at higher temperatures, and at 45 degrees C were associated with differences in respiratory evaporative heat loss, with that of M. giganteus being higher. Panting in kangaroos occurred as a graded increase in respiratory frequency, during which tidal volume was lowered. When panting, the desert red kangaroo had larger tidal volumes and lower respiratory frequencies at equivalent T(a) than the eastern grey kangaroo, which generally inhabits mesic forests. The inference made from this pattern is that the red kangaroo has the potential to increase respiratory evaporative heat loss to a greater level.
Lead toxicity: An overview of prevalence in Indians.
Iyer, Sandhya; Sengupta, Caesar; Velumani, A
2015-12-07
Elements form a basic and natural constituent of the Earth's crust and are released into the atmosphere due to many human activities like mining and manufacturing. Of all, the elements, lead toxicity is a prevailing as well as a growing concern the world over because of its ability to affect multiple clinical functions. Blood lead levels have been analyzed in a large pan-India cohort of 222,668 comprising of 121,115 males and 101,553 females respectively. The cohort included all age groups from <2 to >55 years old. The analytical platform of Inductively Coupled Plasma-Mass Spectrometry has been used to assess lead levels. Blood lead levels of ≥150 μg/L was considered high for analysis. The total frequency of high lead levels detected in our study was 1.16%. The frequency of males affected were higher than females, with the difference being statistically significant.. Lead being ubiquitous in its presence and also serving no biological function, has grown today to become a serious threat to human health. The high frequency of affected detected in our study raises a cause for concern. Determining its presence and the most affected geography in any country will aid in charting guidelines on controlling its release as well as exposure. Copyright © 2015 Elsevier B.V. All rights reserved.
On the effect of acoustic coupling on random and harmonic plate vibrations
NASA Technical Reports Server (NTRS)
Frendi, A.; Robinson, J. H.
1993-01-01
The effect of acoustic coupling on random and harmonic plate vibrations is studied using two numerical models. In the coupled model, the plate response is obtained by integration of the nonlinear plate equation coupled with the nonlinear Euler equations for the surrounding acoustic fluid. In the uncoupled model, the nonlinear plate equation with an equivalent linear viscous damping term is integrated to obtain the response of the plate subject to the same excitation field. For a low-level, narrow-band excitation, the two models predict the same plate response spectra. As the excitation level is increased, the response power spectrum predicted by the uncoupled model becomes broader and more shifted towards the high frequencies than that obtained by the coupled model. In addition, the difference in response between the coupled and uncoupled models at high frequencies becomes larger. When a high intensity harmonic excitation is used, causing a nonlinear plate response, both models predict the same frequency content of the response. However, the level of the harmonics and subharmonics are higher for the uncoupled model. Comparisons to earlier experimental and numerical results show that acoustic coupling has a significant effect on the plate response at high excitation levels. Its absence in previous models may explain the discrepancy between predicted and measured responses.
Chertoff, Mark E.; Earl, Brian R.; Diaz, Francisco J.; Sorensen, Janna L.; Thomas, Megan L. A.; Kamerer, Aryn M.; Peppi, Marcello
2014-01-01
The electrical signal recorded at the round window was used to estimate the location of missing outer hair cells. The cochlear response was recorded to a low frequency tone embedded in high-pass filtered noise conditions. Cochlear damage was created by either overexposure to frequency-specific tones or laser light. In animals with continuous damage along the partition, the amplitude of the cochlear response increased as the high-pass cutoff frequency increased, eventually reaching a plateau. The cochlear distance at the onset of the plateau correlated with the anatomical onset of outer hair cell loss. A mathematical model replicated the physiologic data but was limited to cases with continuous hair cell loss in the middle and basal turns. The neural contribution to the cochlear response was determined by recording the response before and after application of Ouabain. Application of Ouabain eliminated or reduced auditory neural activity from approximately two turns of the cochlea. The amplitude of the cochlear response was reduced for moderate signal levels with a limited effect at higher levels, indicating that the cochlear response was dominated by outer hair cell currents at high signal levels and neural potentials at low to moderate signal levels. PMID:25190395
Carneiro, Cláudia Martins; Martins-Filho, Olindo Assis; Reis, Alexandre Barbosa; Veloso, Vanja Maria; Araújo, Flávio Marcos Gomes; Bahia, Maria Terezinha; de Lana, Marta; Machado-Coelho, George Luiz Lins; Gazzinelli, Giovanni; Correa-Oliveira, Rodrigo; Tafuri, Washington Luiz
2007-02-01
A detailed follow-up investigation of the major parasitological, serological and phenotypic features in dogs experimentally infected with metacyclic (MT) and blood (BT) trypomastigotes of Trypanosoma cruzi strain Berenice-78, typifying vectorial and transfusional transmission of human Chagas disease, has been conducted. Although there were no changes with respect to the window of patent-parasitaemia, significant differences between MT- and BT-infected dogs in both the prepatent period (days 23 and 19, respectively) and the day of maximum parasitaemia (days 26 and 22, respectively) were recorded. A progressive enhancement in the level of T. cruzi-specific antibodies accompanied infection by both MT and BT forms, although higher IgG titres developed on days 14 and 21 following infection with MT forms. Higher Thy-1(+)/CD21(+) and lower CD4(+)/CD8(+) cell ratios, occasioned by increased levels of Thy-1(+) and CD8(+) T-cells and reduced frequencies of CD4(+) T-cells and CD21(+) B-lymphocytes, were observed in both MT- and BT-infected animals. The reduced frequency of CD14(+) leukocytes was revealed as the most relevant phenotypic feature intrinsic to T. cruzi infection independent of inoculum source. BT-specific phenotypic features included an early reduction in the percentage of circulating CD21(+) and CD14(+) leukocytes, together with a higher Thy-1(+)/CD21(+) cell ratio on day 42. On the other hand, higher levels of CD8(+) T-cells, together with a lower CD4(+)/CD8(+) cell ratio on day 28, were characteristic of MT infection. These findings emphasise the importance of inoculum source and suggest that vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during acute Chagas disease.
Çatlı, Gönül; Anık, Ahmet; Ünver Tuhan, Hale; Böber, Ece; Abacı, Ayhan
2014-12-01
To evaluate i) the frequency of typical hypothyroidism symptoms in children with subclinical hypothyroidism (SH), ii) to evaluate the association of SH with lipoproteins and iii) to investigate possible improving effects of L-thyroxine (LT4) treatment on these findings. Twenty-seven children with SH who had elevated thyroid-stimulating hormone (TSH: >4.94 µIU/L) but normal free T4 levels and healthy euthyroid children of similar age and sex were enrolled in the study. Anthropometric and laboratory (lipid profile and thyroid function tests) measurements were performed at diagnosis and six months after euthyroidism was achieved. All children were also subjected to a questionnaire on hypothyroid symptoms at diagnosis. The SH patients were subjected to the questionnaire also following treatment. Pre-treatment data were compared with those of controls and post-treatment measurements. Anthropometric and laboratory parameters of the groups were not statistically different except for higher TSH levels in the SH group. Serum lipoprotein levels and dyslipidemia frequency were similar between the groups. Compared to the controls, hypothyroidism symptom score was significantly higher in the SH group. Six months after euthyroidism was achieved, a significant reduction in the hypothyroid symptom score was obtained in the SH group. Except for significantly higher serum TSH values, no significant differences regarding demographic characteristics, symptom scores and lipid parameters were present between patients with Hashimoto's thyroiditis and the remaining SH patients. The results of this study showed that in children with SH i) the hypothyroidism symptom score was significantly higher than in euthyroid children, ii) LT4 treatment improved the hypothyroidism symptom score and iii) SH does not seem to be associated with dyslipidemia.
Exposure to excessive sounds and hearing status in academic classical music students.
Pawlaczyk-Łuszczyńska, Małgorzata; Zamojska-Daniszewska, Małgorzata; Dudarewicz, Adam; Zaborowski, Kamil
2017-02-21
The aim of this study was to assess hearing of music students in relation to their exposure to excessive sounds. Standard pure-tone audiometry (PTA) was performed in 168 music students, aged 22.5±2.5 years. The control group included 67 subjects, non-music students and non-musicians, aged 22.8±3.3 years. Data on the study subjects' musical experience, instruments in use, time of weekly practice and additional risk factors for noise-induced hearing loss (NIHL) were identified by means of a questionnaire survey. Sound pressure levels produced by various groups of instruments during solo and group playing were also measured and analyzed. The music students' audiometric hearing threshold levels (HTLs) were compared with the theoretical predictions calculated according to the International Organization for Standardization standard ISO 1999:2013. It was estimated that the music students were exposed for 27.1±14.3 h/week to sounds at the A-weighted equivalent-continuous sound pressure level of 89.9±6.0 dB. There were no significant differences in HTLs between the music students and the control group in the frequency range of 4000-8000 Hz. Furthermore, in each group HTLs in the frequency range 1000-8000 Hz did not exceed 20 dB HL in 83% of the examined ears. Nevertheless, high frequency notched audiograms typical of the noise-induced hearing loss were found in 13.4% and 9% of the musicians and non-musicians, respectively. The odds ratio (OR) of notching in the music students increased significantly along with higher sound pressure levels (OR = 1.07, 95% confidence interval (CI): 1.014-1.13, p < 0.05). The students' HTLs were worse (higher) than those of a highly screened non-noise-exposed population. Moreover, their hearing loss was less severe than that expected from sound exposure for frequencies of 3000 Hz and 4000 Hz, and it was more severe in the case of frequency of 6000 Hz. The results confirm the need for further studies and development of a hearing conservation program for music students. Int J Occup Med Environ Health 2017;30(1):55-75. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.
Real World Testing Of A Piezoelectric Rotational Energy Harvester For Human Motion
NASA Astrophysics Data System (ADS)
Pillatsch, P.; Yeatman, E. M.; Holmes, A. S.
2013-12-01
Harvesting energy from human motion is challenging because the frequencies are generally low and random compared to industrial machinery that vibrates at much higher frequencies. One of the most promising and popular strategies to overcome this is frequency up-conversion. The transducing element is actuated at its optimal frequency of operation, higher than the source excitation frequency, through some kind of catch and release mechanism. This is beneficial for efficient power generation. Such devices have now been investigated for a few years and this paper takes a previously introduced piezoelectric rotational harvester, relying on beam plucking for the energy conversion, to the next step by testing the device during a half marathon race. The prototype and data acquisition system are described in detail and the experimental results presented. A comparison of the input excitation, based on an accelerometer readout, and the output voltage of the piezoelectric beam, recorded at the same time, confirm the successful implementation of the system. For a device functional volume of 1.85 cm3, a maximum power output of 7 μW was achieved when the system was worn on the upper arm. However, degradation of the piezoelectric material meant that the performance dropped rapidly from this initial level; this requires further research. Furthermore, the need for intermediate energy storage solutions is discussed, as human motion harvesters only generate power as long as the wearer is actually moving.
Alcohol marketing in televised international football: frequency analysis.
Adams, Jean; Coleman, James; White, Martin
2014-05-20
Alcohol marketing includes sponsorship of individuals, organisations and sporting events. Football (soccer) is one of the most popular spectator sports worldwide. No previous studies have quantified the frequency of alcohol marketing in a high profile international football tournament. The aims were to determine: the frequency and nature of visual references to alcohol in a representative sample of EURO2012 matches broadcast in the UK; and if frequency or nature varied between matches broadcast on public service and commercial channels, or between matches that did and did not feature England. Eight matches selected by stratified random sampling were recorded. All visual references to alcohol were identified using a tool with high inter-rater reliability. 1846 visual references to alcohol were identified over 1487 minutes of broadcast--an average of 1.24 references per minute. The mean number of references per minute was higher in matches that did vs did not feature England (p = 0.004), but did not differ between matches broadcast on public service vs commercial channels (p = 0.92). The frequency of visual references to alcohol was universally high and higher in matches featuring the only UK home team--England--suggesting that there may be targeting of particularly highly viewed matches. References were embedded in broadcasts, and not particular to commercial channels including paid-for advertising. New UK codes-of-conduct on alcohol marketing at sporting events will not reduce the level of marketing reported here.
The signatures of acoustic emission waveforms from fatigue crack advancing in thin metallic plates
NASA Astrophysics Data System (ADS)
Yeasin Bhuiyan, Md; Giurgiutiu, Victor
2018-01-01
The acoustic emission (AE) waveforms from a fatigue crack advancing in a thin metallic plate possess diverse and complex spectral signatures. In this article, we analyze these waveform signatures in coordination with the load level during cyclic fatigue. The advancing fatigue crack may generate numerous AE hits while it grows under fatigue loading. We found that these AE hits can be sorted into various groups based on their AE waveform signatures. Each waveform group has a particular time-domain signal pattern and a specific frequency spectrum. This indicates that each group represents a certain AE event related to the fatigue crack growth behavior. In situ AE-fatigue experiments were conducted to monitor the fatigue crack growth with simultaneous measurement of AE signals, fatigue loading, and optical crack growth measurement. An in situ microscope was installed in the load-frame of the mechanical testing system (MTS) to optically monitor the fatigue crack growth and relate the AE signals with the crack growth measurement. We found the AE signal groups at higher load levels (75%-85% of maximum load) were different from the AE signal groups that happened at lower load levels (below 60% of load level). These AE waveform groups are highly related to the fatigue crack-related AE events. These AE signals mostly contain the higher frequency peaks (100 kHz, 230 kHz, 450 kHz, 550 kHz). Some AE signal groups happened as a clustered form that relates a sequence of small AE events within the fatigue crack. They happened at relatively lower load level (50%-60% of the maximum load). These AE signal groups may be related to crack friction and micro-fracture during the friction process. These AE signals mostly contain the lower frequency peaks (60 kHz, 100 kHz, 200 kHz). The AE waveform based analysis may give us comprehensive information of the metal fatigue.
Plasma levels of serotonin, gastrointestinal symptoms,and sleep problems in children with autism.
Kheirouri, Sorayya; Kalejahi, Parinaz; Noorazar, Seyyed Gholamreza
2016-12-20
Autism is a neurodevelopmental disorder identified with higher frequency of serotonin abnormalities and gastrointestinal (GI) and sleep problems. This study aimed to evaluate the plasma levels of serotonin, GI symptoms, and sleep problems, and their relationship with autism severity in children with autism. Thirty-five children with autism and 31 healthy subjects were studied. GI problems, sleep disorders, and severity of disorder were assessed. Plasma serotonin was determined using ELISA. There was no significant association between GI problems and autism severity, but a significant positive correlation was seen between different indicators of sleep disorder and severity of autism. Plasma levels of serotonin were significantly higher in autistic children and a significant negative correlation was observed between plasma levels of serotonin and autism severity (r = -0.39, P = 0.02). Elevated plasma serotonin in autistic children and its negative correlation with disease severity may indicate involvement of the neurotransmitter in the neurophysiologic mechanism of autism.
Geographic Variation in Festuca rubra L. Ploidy Levels and Systemic Fungal Endophyte Frequencies.
Dirihan, Serdar; Helander, Marjo; Väre, Henry; Gundel, Pedro E; Garibaldi, Lucas A; Irisarri, J Gonzalo N; Saloniemi, Irma; Saikkonen, Kari
2016-01-01
Polyploidy and symbiotic Epichloë fungal endophytes are common and heritable characteristics that can facilitate environmental range expansion in grasses. Here we examined geographic patterns of polyploidy and the frequency of fungal endophyte colonized plants in 29 Festuca rubra L. populations from eight geographic sites across latitudes from Spain to northernmost Finland and Greenland. Ploidy seemed to be positively and negatively correlated with latitude and productivity, respectively. However, the correlations were nonlinear; 84% of the plants were hexaploids (2n = 6x = 42), and the positive correlation between ploidy level and latitude is the result of only four populations skewing the data. In the southernmost end of the gradient 86% of the plants were tetraploids (2n = 4x = 28), whereas in the northernmost end of the gradient one population had only octoploid plants (2n = 8x = 56). Endophytes were detected in 22 out of the 29 populations. Endophyte frequencies varied among geographic sites, and populations and habitats within geographic sites irrespective of ploidy, latitude or productivity. The highest overall endophyte frequencies were found in the southernmost end of the gradient, Spain, where 69% of plants harbored endophytes. In northern Finland, endophytes were detected in 30% of grasses but endophyte frequencies varied among populations from 0% to 75%, being higher in meadows compared to riverbanks. The endophytes were detected in 36%, 30% and 27% of the plants in Faroe Islands, Iceland and Switzerland, respectively. Practically all examined plants collected from southern Finland and Greenland were endophyte-free, whereas in other geographic sites endophyte frequencies were highly variable among populations. Common to all populations with high endophyte frequencies is heavy vertebrate grazing. We propose that the detected endophyte frequencies and ploidy levels mirror past distribution history of F. rubra after the last glaciation period, and local adaptations to past or prevailing selection forces such as vertebrate grazing.
Geographic Variation in Festuca rubra L. Ploidy Levels and Systemic Fungal Endophyte Frequencies
Dirihan, Serdar; Helander, Marjo; Väre, Henry; Gundel, Pedro E.; Garibaldi, Lucas A.; Irisarri, J. Gonzalo N.; Saloniemi, Irma; Saikkonen, Kari
2016-01-01
Polyploidy and symbiotic Epichloë fungal endophytes are common and heritable characteristics that can facilitate environmental range expansion in grasses. Here we examined geographic patterns of polyploidy and the frequency of fungal endophyte colonized plants in 29 Festuca rubra L. populations from eight geographic sites across latitudes from Spain to northernmost Finland and Greenland. Ploidy seemed to be positively and negatively correlated with latitude and productivity, respectively. However, the correlations were nonlinear; 84% of the plants were hexaploids (2n = 6x = 42), and the positive correlation between ploidy level and latitude is the result of only four populations skewing the data. In the southernmost end of the gradient 86% of the plants were tetraploids (2n = 4x = 28), whereas in the northernmost end of the gradient one population had only octoploid plants (2n = 8x = 56). Endophytes were detected in 22 out of the 29 populations. Endophyte frequencies varied among geographic sites, and populations and habitats within geographic sites irrespective of ploidy, latitude or productivity. The highest overall endophyte frequencies were found in the southernmost end of the gradient, Spain, where 69% of plants harbored endophytes. In northern Finland, endophytes were detected in 30% of grasses but endophyte frequencies varied among populations from 0% to 75%, being higher in meadows compared to riverbanks. The endophytes were detected in 36%, 30% and 27% of the plants in Faroe Islands, Iceland and Switzerland, respectively. Practically all examined plants collected from southern Finland and Greenland were endophyte-free, whereas in other geographic sites endophyte frequencies were highly variable among populations. Common to all populations with high endophyte frequencies is heavy vertebrate grazing. We propose that the detected endophyte frequencies and ploidy levels mirror past distribution history of F. rubra after the last glaciation period, and local adaptations to past or prevailing selection forces such as vertebrate grazing. PMID:27846291
High Efficiency Transformation of Cultured Tobacco Cells 1
An, Gynheung
1985-01-01
Tobacco calli were transformed at levels up to 50% by cocultivation of tobacco cultured cells with Agrobacterium tumefaciens harboring the binary transfer-DNA vector, pGA472, containing a kanamycin resistance marker. Transformation frequency was dependent on the physiological state of the tobacco cells, the nature of Agrobacterium strain and, less so, on the expression of the vir genes of the tumor-inducing plasmid. Maximum transformation frequency was obtained with exponentially growing plant cells, suggesting that rapid growth of plant cells is an essental factor for efficient transformation of higher plants. Images Fig. 1 PMID:16664453
Two-photon spectroscopy of excitons with entangled photons.
Schlawin, Frank; Mukamel, Shaul
2013-12-28
The utility of quantum light as a spectroscopic tool is demonstrated for frequency-dispersed pump-probe, integrated pump-probe, and two-photon fluorescence signals which show Ramsey fringes. Simulations of the frequency-dispersed transmission of a broadband pulse of entangled photons interacting with a three-level model of matter reveal how the non-classical time-bandwidth properties of entangled photons can be used to disentangle congested spectra, and reveal otherwise unresolved features. Quantum light effects are most pronounced at weak intensities when entangled photon pairs are well separated, and are gradually diminished at higher intensities when different photon pairs overlap.
Two-photon spectroscopy of excitons with entangled photons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schlawin, Frank, E-mail: Frank.Schlawin@physik.uni-freiburg.de; Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Straße 3, 79108 Freiburg; Mukamel, Shaul, E-mail: smukamel@uci.edu
The utility of quantum light as a spectroscopic tool is demonstrated for frequency-dispersed pump-probe, integrated pump-probe, and two-photon fluorescence signals which show Ramsey fringes. Simulations of the frequency-dispersed transmission of a broadband pulse of entangled photons interacting with a three-level model of matter reveal how the non-classical time-bandwidth properties of entangled photons can be used to disentangle congested spectra, and reveal otherwise unresolved features. Quantum light effects are most pronounced at weak intensities when entangled photon pairs are well separated, and are gradually diminished at higher intensities when different photon pairs overlap.
1983-09-01
adult man (full-scale height = 171 cm) and child (full-scale height = 86 cm), with arms down. We used the full-scale figure to reflect a worst-case... child for all orientations was much higher than that for the adult (e.g., 0.187 W/kg versus 0.063 W/kg), which is expected since the frequency is closer...to the resonance frequency for the child . Another series of scale-model measurements was conducted for determination of the average SAR values for
Responding to nonwords in the lexical decision task: Insights from the English Lexicon Project.
Yap, Melvin J; Sibley, Daragh E; Balota, David A; Ratcliff, Roger; Rueckl, Jay
2015-05-01
Researchers have extensively documented how various statistical properties of words (e.g., word frequency) influence lexical processing. However, the impact of lexical variables on nonword decision-making performance is less clear. This gap is surprising, because a better specification of the mechanisms driving nonword responses may provide valuable insights into early lexical processes. In the present study, item-level and participant-level analyses were conducted on the trial-level lexical decision data for almost 37,000 nonwords in the English Lexicon Project in order to identify the influence of different psycholinguistic variables on nonword lexical decision performance and to explore individual differences in how participants respond to nonwords. Item-level regression analyses reveal that nonword response time was positively correlated with number of letters, number of orthographic neighbors, number of affixes, and base-word number of syllables, and negatively correlated with Levenshtein orthographic distance and base-word frequency. Participant-level analyses also point to within- and between-session stability in nonword responses across distinct sets of items, and intriguingly reveal that higher vocabulary knowledge is associated with less sensitivity to some dimensions (e.g., number of letters) but more sensitivity to others (e.g., base-word frequency). The present findings provide well-specified and interesting new constraints for informing models of word recognition and lexical decision. (c) 2015 APA, all rights reserved).
Ezzidi, Intissar; Mtiraoui, Nabil; Kacem, Maha; Chaieb, Molka; Mahjoub, Touhami; Almawi, Wassim Y
2009-11-01
Cross-sectional and family studies identified angiotensin-converting enzyme (ACE) gene as a risk factor for diabetic nephropathy (DN). The contribution of ACE gene variants to DN development and progression is controversial and varies among different ethnic/racial groups. We investigated the association of three ACE gene variants with DN, rs1799752 insertion/deletion (I/D), rs1800764T/C and rs12449782A/G in 917 Tunisian type 2 diabetic (T2DM) patients: 515 with (DN) and 402 without (DWN) nephropathy. ACE genotyping was done by PCR-based assays; haplotype estimation was performed using H-Plus software (chi(2)-test based). Genotype frequency distributions of the three studied variants were in Hardy-Weinberg equilibrium. Minor allele frequency of rs1800764 was higher in DN patients than DWN patients or healthy controls, and minor allele frequency of rs1799752 was higher in DN than DWN patients. Higher frequency of rs1799752 and rs1800764 homozygous mutant genotypes was seen in DN compared to DWN patients. Of the three variants, only rs1799752 deletion/deletion (D/D) genotype was associated with a significant increase in albumin to creatinine ratios levels, and D/D carriers had elevated low-density lipoprotein, total cholesterol and urea. Three locus haplotype [rs1799752(I/D)/rs1800764(T/C)/rs12449782(A/G)] analysis revealed that the frequency of DCG haplotype was higher, while that of ITG and ICA haplotypes were lower among unselected type 2 diabetic patients. Taking ITA haplotype as reference, multivariate regression analysis confirmed the negative (ITG), and positive (DCG, DTG, DCA and DTA) association of specific ACE haplotypes with DN, after adjusting for potential nephropathy-linked covariates. Our results support the involvement of specific ACE variants in DN pathogenesis and demonstrate the presence of DN-specific haplotypes at the ACE locus.
Shaping and timing gradient pulses to reduce MRI acoustic noise.
Segbers, Marcel; Rizzo Sierra, Carlos V; Duifhuis, Hendrikus; Hoogduin, Johannes M
2010-08-01
A method to reduce the acoustic noise generated by gradient systems in MRI has been recently proposed; such a method is based on the linear response theory. Since the physical cause of MRI acoustic noise is the time derivative of the gradient current, a common trapezoid current shape produces an acoustic gradient coil response mainly during the rising and falling edge. In the falling edge, the coil acoustic response presents a 180 degrees phase difference compared to the rising edge. Therefore, by varying the width of the trapezoid and keeping the ramps constant, it is possible to suppress one selected frequency and its higher harmonics. This value is matched to one of the prominent resonance frequencies of the gradient coil system. The idea of cancelling a single frequency is extended to a second frequency, using two successive trapezoid-shaped pulses presented at a selected interval. Overall sound pressure level reduction of 6 and 10 dB is found for the two trapezoid shapes and a single pulse shape, respectively. The acoustically optimized pulse shape proposed is additionally tested in a simulated echo planar imaging readout train, obtaining a sound pressure level reduction of 12 dB for the best case.
Severe tophaceous gout and disability: changes in the past 15 years.
López López, Carlos Omar; Lugo, Everardo Fuentes; Alvarez-Hernández, Everardo; Peláez-Ballestas, Ingris; Burgos-Vargas, Rubén; Vázquez-Mellado, Janitzia
2017-01-01
Epidemiologic data from recent decades show a significant increase in the prevalence and incidence of gout worldwide, in addition to changes in its clinical expression. Our objective was to compare the frequency of the severity of gout and disability in two patient groups at our clinic during different periods. We included and compared data of two groups: group A (1995-2000), patients from previous report, and group B (2010-2014), the baseline data of current patients participating in a cohort (GRESGO). This evaluation included data of socioeconomic and educational levels, demographics, associated diseases, previous treatment, clinical and biochemical data, and disability evaluated using the Health Assessment Questionnaire (HAQ). We included data of 564 gout patients. Participants were 35.7 ± 12.7 years old at onset and had 12.0 ± 9.2-years disease duration at their first evaluation in our department. Group B patients were younger, had higher educational and socioeconomic levels, and had more severe disease. However, this group had less frequency of some associated diseases and significantly higher HAQ scores. With increased HAQ score, a higher number of acute flares and tender, limited-to-motion, and swollen joints were seen. The spectrum of gout has changed over the past decade. A higher percentage of our patients had a severe form of disease, were younger, had earlier disease onset, and had more disability reflected in higher HAQ scores. In our current patient group, the variable most associated with disability was limited-to-motion joints; however, the number of acute flares and tender and swollen joints was also higher in patients with greater disability.
Alcohol consumption and visual impairment in a rural Northern Chinese population.
Li, Zhijian; Xu, Keke; Wu, Shubin; Sun, Ying; Song, Zhen; Jin, Di; Liu, Ping
2014-12-01
To investigate alcohol drinking status and the association between drinking patterns and visual impairment in an adult population in northern China. Cluster sampling was used to select samples. The protocol consisted of an interview, pilot study, visual acuity (VA) testing and a clinical examination. Visual impairment was defined as presenting VA worse than 20/60 in any eye. Drinking patterns included drinking quantity (standard drinks per week) and frequency (drinking days in the past week). Information on alcohol consumption was obtained from 8445 subjects, 963 (11.4%) of whom reported consuming alcohol. In multivariate analysis, alcohol consumption was significantly associated with older age (p < 0.001), male sex (p < 0.001), and higher education level (p < 0.01). Heavy intake (>14 drinks/week) was associated with higher odds of visual impairment. However, moderate intake (>1-14 drinks/week) was significantly associated with lower odds (adjusted odds ratio, OR, 0.7, 95% confidence interval, CI, 0.5-1.0) of visual impairment (p = 0.03). Higher drinking frequency was significantly associated with higher odds of visual impairment. Multivariate analysis showed that older age, male sex, and higher education level were associated with visual impairment among current drinkers. Age- and sex-adjusted ORs for the association of cataract and alcohol intake showed that higher alcohol consumption was not significantly associated with an increased prevalence of cataract (OR 1.2, 95% CI 0.4-3.6), whereas light and moderate alcohol consumption appeared to reduce incidence of cataract. Drinking patterns were associated with visual impairment. Heavy intake had negative effects on distance vision; meanwhile, moderate intake had a positive effect on distance vision.
Marcano, Teodardo José; Morgado, Anastácio; Tosta, Carlos Eduardo; Coura, José Rodrigues
2004-06-01
It is well established that immunity to malaria is short-lived and is maintained by the continuous contact with the parasite. We now show that the stable transmission of malaria in Yanomami Amerindian communities maintains a degree of immunity in the exposed population capable to reduce prevalence and morbidity of malaria. We examined 508 Yanomami Amerindians living along Orinoco (407) and Mucajaí (101) rivers, on the Venezuelan and Brazilian Amazon region, respectively. At Orinoco villages, malaria was hyperendemic and presented stable transmission, while at Mucajaí villages it was mesoendemic and showed unstable transmission. The frequency of Plasmodium vivax and P. falciparum was roughly comparable in Venezuelan and Brazilian communities. Malaria presented different profiles at Orinoco and Mucajaí villages. In the former communities, malaria showed a lower prevalence (16% x 40.6%), particularly among those over 10 years old (5.2% x 34.8%), a higher frequency of asymptomatic cases (38.5% x 4.9%), and a lower frequency of cases of severe malaria (9.2% x 36.5%). Orinoco villagers also showed a higher reactivity of the immune system, measured by the frequency of splenomegaly (72.4% x 29.7%) and by the splenic index (71.4% over level 1 x 28.6), and higher prevalence (91.1% x 72.1%) and mean titer (1243 x 62) of antiplasmodial IgG antibodies, as well as a higher prevalence (77.4% x 24.7%) and mean titer (120 x 35) of antiplasmodial IgM antibodies. Our findings show that in isolated Yanomami communities the stability of malaria transmission, and the consequent continuous activation of the immune system of the exposed population, leads to the reduction of malaria prevalence and morbidity.
Chirp- and random-based coded ultrasonic excitation for localized blood-brain barrier opening
Kamimura, HAS; Wang, S; Wu, S-Y; Karakatsani, ME; Acosta, C; Carneiro, AAO; Konofagou, EE
2015-01-01
Chirp- and random-based coded excitation methods have been proposed to reduce standing wave formation and improve focusing of transcranial ultrasound. However, no clear evidence has been shown to support the benefits of these ultrasonic excitation sequences in vivo. This study evaluates the chirp and periodic selection of random frequency (PSRF) coded-excitation methods for opening the blood-brain barrier (BBB) in mice. Three groups of mice (n=15) were injected with polydisperse microbubbles and sonicated in the caudate putamen using the chirp/PSRF coded (bandwidth: 1.5-1.9 MHz, peak negative pressure: 0.52 MPa, duration: 30 s) or standard ultrasound (frequency: 1.5 MHz, pressure: 0.52 MPa, burst duration: 20 ms, duration: 5 min) sequences. T1-weighted contrast-enhanced MRI scans were performed to quantitatively analyze focused ultrasound induced BBB opening. The mean opening volumes evaluated from the MRI were 9.38±5.71 mm3, 8.91±3.91 mm3 and 35.47 ± 5.10 mm3 for the chirp, random and regular sonications, respectively. The mean cavitation levels were 55.40±28.43 V.s, 63.87±29.97 V.s and 356.52±257.15 V.s for the chirp, random and regular sonications, respectively. The chirp and PSRF coded pulsing sequences improved the BBB opening localization by inducing lower cavitation levels and smaller opening volumes compared to results of the regular sonication technique. Larger bandwidths were associated with more focused targeting but were limited by the frequency response of the transducer, the skull attenuation and the microbubbles optimal frequency range. The coded methods could therefore facilitate highly localized drug delivery as well as benefit other transcranial ultrasound techniques that use higher pressure levels and higher precision to induce the necessary bioeffects in a brain region while avoiding damage to the surrounding healthy tissue. PMID:26394091
Mostafa, Gehan Ahmed; Al-Ayadhi, Laila Yousef
2011-06-22
One of the most consistent biological findings in autism is the elevated blood serotonin levels. Immune abnormalities, including autoimmunity with production of brain specific auto-antibodies, are also commonly observed in this disorder. Hyperserotonemia may be one of the contributing factors to autoimmunity in some patients with autism through the reduction of T-helper (Th) 1-type cytokines. We are the first to investigate the possible role of hyperserotonemia in the induction of autoimmunity, as indicated by serum anti-myelin-basic protein (anti-MBP) auto-antibodies, in autism. Serum levels of serotonin and anti-MBP auto-antibodies were measured, by ELISA, in 50 autistic patients, aged between 5 and 12 years, and 30 healthy-matched children. Autistic children had significantly higher serum levels of serotonin and anti-MBP auto-antibodies than healthy children (P < 0.001 and P < 0.001, respectively). Increased serum levels of serotonin and anti-MBP auto-antibodies were found in 92% and 80%, respectively of autistic patients. Patients with severe autism had significantly higher serum serotonin levels than children with mild to moderate autism (P < 0.001). Serum serotonin levels had no significant correlations with serum levels of anti-MBP auto-antibodies in autistic patients (P = 0.39). Hyperserotonemia may not be one of the contributing factors to the increased frequency of serum anti-MBP auto-antibodies in some autistic children. These data should be treated with caution until further investigations are performed. However, inclusion of serum serotonin levels as a correlate may be useful in other future immune studies in autism to help unravel the long-standing mystery of hyperserotonemia and its possible role in the pathophysiology of this disorder.
2011-01-01
Background One of the most consistent biological findings in autism is the elevated blood serotonin levels. Immune abnormalities, including autoimmunity with production of brain specific auto-antibodies, are also commonly observed in this disorder. Hyperserotonemia may be one of the contributing factors to autoimmunity in some patients with autism through the reduction of T-helper (Th) 1-type cytokines. We are the first to investigate the possible role of hyperserotonemia in the induction of autoimmunity, as indicated by serum anti-myelin-basic protein (anti-MBP) auto-antibodies, in autism. Methods Serum levels of serotonin and anti-MBP auto-antibodies were measured, by ELISA, in 50 autistic patients, aged between 5 and 12 years, and 30 healthy-matched children. Results Autistic children had significantly higher serum levels of serotonin and anti-MBP auto-antibodies than healthy children (P < 0.001 and P < 0.001, respectively). Increased serum levels of serotonin and anti-MBP auto-antibodies were found in 92% and 80%, respectively of autistic patients. Patients with severe autism had significantly higher serum serotonin levels than children with mild to moderate autism (P < 0.001). Serum serotonin levels had no significant correlations with serum levels of anti-MBP auto-antibodies in autistic patients (P = 0.39). Conclusions Hyperserotonemia may not be one of the contributing factors to the increased frequency of serum anti-MBP auto-antibodies in some autistic children. These data should be treated with caution until further investigations are performed. However, inclusion of serum serotonin levels as a correlate may be useful in other future immune studies in autism to help unravel the long-standing mystery of hyperserotonemia and its possible role in the pathophysiology of this disorder. PMID:21696608
Effects of chromium picolinate on micronucleus frequency and morphology of lymphocytes in calves.
Imamoğlu, Nalan; Uyanik, Fatma; Kocaoğlu Güçlü, Berrin; Erdem, Onur; Cem Liman, Bilal; Dönmez Altuntaş, Hamiyet
2008-11-01
We report the effects of chromium picolinate (CrPic) on micronucleus frequency, morphology of lymphocytes, and lipid peroxidation in calves. Twenty-four Holstein calves were selected for the study. They were kept in a farm and were fed a commercially available calf diet and alfalfa, ad libitum. The animals were divided into three groups of eight subjects each and were treated as follows: The first group was supplemented with a daily dose of 200 microg Cr as chromium picolinate; a second group received 400 microg Cr per day and a third group that served as control received no supplemental chromium. After 12-week supplementation, blood samples were collected to determine the micronucleus frequency, the apoptotic cell percentage, and the malondialdehyde (MDA) and blood chromium levels. In both supplemented groups, the cells had irregularly shaped and segmented nuclei. Supplementation also increased the percentage of apoptotic cells (p < 0.001) and serum MDA (p < 0.01) and slightly increased the chromium levels. The animals supplemented with 400 microg showed a significant increase of micronucleus frequency (p < 0.01). The results of this study suggest that supplementation with 200 and 400 microg chromium as chromium picolinate may lead to cytotoxicity. The higher level of supplementation may also have genotoxic effects. However, further studies investigating the mechanism of the action of CrPic are required.
He, Xiyang; Zhang, Xiaohong; Tang, Long; Liu, Wanke
2015-12-22
Many applications, such as marine navigation, land vehicles location, etc., require real time precise positioning under medium or long baseline conditions. In this contribution, we develop a model of real-time kinematic decimeter-level positioning with BeiDou Navigation Satellite System (BDS) triple-frequency signals over medium distances. The ambiguities of two extra-wide-lane (EWL) combinations are fixed first, and then a wide lane (WL) combination is reformed based on the two EWL combinations for positioning. Theoretical analysis and empirical analysis is given of the ambiguity fixing rate and the positioning accuracy of the presented method. The results indicate that the ambiguity fixing rate can be up to more than 98% when using BDS medium baseline observations, which is much higher than that of dual-frequency Hatch-Melbourne-Wübbena (HMW) method. As for positioning accuracy, decimeter level accuracy can be achieved with this method, which is comparable to that of carrier-smoothed code differential positioning method. Signal interruption simulation experiment indicates that the proposed method can realize fast high-precision positioning whereas the carrier-smoothed code differential positioning method needs several hundreds of seconds for obtaining high precision results. We can conclude that a relatively high accuracy and high fixing rate can be achieved for triple-frequency WL method with single-epoch observations, displaying significant advantage comparing to traditional carrier-smoothed code differential positioning method.
225-255-GHz InP DHBT Frequency Tripler MMIC Using Complementary Split-Ring Resonator
NASA Astrophysics Data System (ADS)
Li, Xiao; Zhang, Yong; Li, Oupeng; Sun, Yan; Lu, Haiyan; Cheng, Wei; Xu, Ruimin
2017-02-01
In this paper, a novel design of frequency tripler monolithic microwave integrated circuit (MMIC) using complementary split-ring resonator (CSRR) is proposed based on 0.5-μm InP DHBT process. The CSRR-loaded microstrip structure is integrated in the tripler as a part of impedance matching network to suppress the fundamental harmonic, and another frequency tripler based on conventional band-pass filter is presented for comparison. The frequency tripler based on CSRR-loaded microstrip generates an output power between -8 and -4 dBm from 228 to 255 GHz when the input power is 6 dBm. The suppression of fundamental harmonic is better than 20 dBc at 77-82 GHz input frequency within only 0.15 × 0.15 mm2 chip area of the CSRR structure on the ground layer. Compared with the frequency tripler based on band-pass filter, the tripler using CSRR-loaded microstrip obtains a similar suppression level of unwanted harmonics and higher conversion gain within a much smaller chip area. To our best knowledge, it is the first time that CSRR is used for harmonic suppression of frequency multiplier at such high frequency band.
Response of plasma rotation to resonant magnetic perturbations in J-TEXT tokamak
NASA Astrophysics Data System (ADS)
Yan, W.; Chen, Z. Y.; Huang, D. W.; Hu, Q. M.; Shi, Y. J.; Ding, Y. H.; Cheng, Z. F.; Yang, Z. J.; Pan, X. M.; Lee, S. G.; Tong, R. H.; Wei, Y. N.; Dong, Y. B.; J-TEXT Team
2018-03-01
The response of plasma toroidal rotation to the external resonant magnetic perturbations (RMP) has been investigated in Joint Texas Experimental Tokamak (J-TEXT) ohmic heating plasmas. For the J-TEXT’s plasmas without the application of RMP, the core toroidal rotation is in the counter-current direction while the edge rotation is near zero or slightly in the co-current direction. Both static RMP experiments and rotating RMP experiments have been applied to investigate the plasma toroidal rotation. The core toroidal rotation decreases to lower level with static RMP. At the same time, the edge rotation can spin to more than 20 km s-1 in co-current direction. On the other hand, the core plasma rotation can be slowed down or be accelerated with the rotating RMP. When the rotating RMP frequency is higher than mode frequency, the plasma rotation can be accelerated to the rotating RMP frequency. The plasma confinement is improved with high frequency rotating RMP. The plasma rotation is decelerated to the rotating RMP frequency when the rotating RMP frequency is lower than the mode frequency. The plasma confinement also degrades with low frequency rotating RMP.
Different behavioural responses to anthropogenic noise by two closely related passerine birds
Francis, Clinton D.; Ortega, Catherine P.; Cruz, Alexander
2011-01-01
Anthropogenic noise, now common to many landscapes, can impair acoustic communication for many species, yet some birds compensate for masking by noise by altering their songs. The phylogenetic distribution of these noise-dependent signal adjustments is uncertain, and it is not known whether closely related species respond similarly to noise. Here, we investigated the influence of noise on habitat occupancy rates and vocal frequency in two congeneric vireos with similar song features. Noise exposure did not influence occupancy rates for either species, yet song features of both changed, albeit in different ways. With increases in noise levels, plumbeous vireos (Vireo plumbeus) sang shorter songs with higher minimum frequencies. By contrast, grey vireos (Vireo vicinior) sang longer songs with higher maximum frequencies. These findings support the notion that vocal plasticity may help some species occupy noisy areas, but because there were no commonalities among the signal changes exhibited by these closely related birds, it may be difficult to predict how diverse species may modify their signals in an increasingly noisy world. PMID:21613284
Baseline coral disease surveys within three marine parks in Sabah, Borneo.
Miller, Jennifer; Sweet, Michael J; Wood, Elizabeth; Bythell, John
2015-01-01
Two of the most significant threats to coral reefs worldwide are bleaching and disease. However, there has been a scarcity of research on coral disease in South-East Asia, despite the high biodiversity and the strong dependence of local communities on the reefs in the region. This study provides baseline data on coral disease frequencies within three national parks in Sabah, Borneo, which exhibit different levels of human impacts and management histories. High mean coral cover (55%) and variable disease frequency (mean 0.25 diseased colonies m(-2)) were found across the three sites. Highest disease frequency (0.44 diseased colonies per m(2)) was seen at the site closest to coastal population centres. Bleaching and pigmentation responses were actually higher at Sipadan, the more remote, offshore site, whereas none of the other coral diseases detected in the other two parks were detected in Sipadan. Results of this study offer a baseline dataset of disease in these parks and indicate the need for continued monitoring, and suggest that coral colonies in parks under higher anthropogenic stressors and with lower coral cover may be more susceptible to contracting disease.
Blanchard, Edward B; Rowell, Dianna; Kuhn, Eric; Rogers, Rebecca; Wittrock, David
2005-01-01
As a follow-up to our earlier report [Behav. Res. Ther., in press] on the level of posttraumatic stress symptoms (PTSS), depressive symptoms, and frequency of diagnoses of probable posttraumatic stress disorder (PTSD) among college students at three public universities (Albany, NY, Augusta, GA, and Fargo, ND) resulting from the September 11, 2001. Terrorist attacks, we surveyed comparable groups of students (total, n = 1313) from these three institutions in the weeks following the first anniversary (2002) of the attacks. We found proximity effects (Albany higher than Augusta which was higher than Fargo) for PTSS and depressive symptoms but not for frequency of diagnoses of probable PTSD. Within the Albany site data, proximity of county of residence to New York City (NYC) also showed a proximity effect on PTSS. Although depressive symptoms were significantly different in 2002 versus 2001, the arithmetic differences in PTSS or in frequency of diagnoses of probable PTSD were not significant. The September 11 attacks continued to exert a psychic toll on college students even a year later.
Glutathione S-Transferase Gene Polymorphisms: Modulator of Genetic Damage in Gasoline Pump Workers.
Priya, Kanu; Yadav, Anita; Kumar, Neeraj; Gulati, Sachin; Aggarwal, Neeraj; Gupta, Ranjan
2015-01-01
This study investigated genetic damage in gasoline pump workers using the cytokinesis blocked micronucleus (CBMN) assay. Blood and urine samples were collected from 50 gasoline pump workers and 50 control participants matched with respect to age and other confounding factors except for exposure to benzene through gasoline vapors. To determine the benzene exposure, phenol was analyzed in urinary samples of exposed and control participants. Urinary mean phenol level was found to be significantly high (P < 0.05) in exposed workers. The CBMN frequency was found to be significantly higher in gasoline pump workers (6.70 ± 1.78) when compared to control individuals (2.20 ± 0.63; P < 0.05). We also investigated influence of polymorphisms of GSTM1, GSTT1, and GSTP1 genes on CBMN frequency. The individuals having GSTM1 and GSTT1 null genotypes had significantly higher frequency of CBMN (P < 0.05). Our study indicates that chronic and long-term exposure of gasoline vapors can increase genotoxic risk in gasoline pump workers. © The Author(s) 2015.
Benzimidazole resistance in equine cyathostomins in India.
Kumar, Sunil; Garg, Rajat; Kumar, Saroj; Banerjee, P S; Ram, Hira; Prasad, A
2016-03-15
Benzimidazole resistance is a major hindrance to the control of equine cyathostominosis throughout the world. There is a paucity of knowledge on the level of benzimidazole resistance in small strongyles of horses in India. In the present study, allele-specific PCR (AS-PCR) that detects F200Y mutation of the isotype 1 β-tubulin gene and faecal egg count reduction test (FECRT) were used for detecting benzimidazole resistance in equine cyathostomin populations in different agro-climatic zones of Uttar Pradesh, India. Results of the FECRT revealed prevalence of benzimidazole resistance in cyathostomins in an intensively managed equine farm in the mid-western plain (FECR=27.5%, LCI=0) and in working horses (extensively managed) at three locations in central plains of Uttar Pradesh (FECR=75.7-83.6%, LCI=29-57%). Post-treatment larval cultures revealed the presence of exclusively cyathostomin larvae. Genotyping of cyathostomin larvae by AS-PCR revealed that the frequency of homozygous resistant (rr) individuals and the resistant allele frequency was significantly higher (p<0.001) in the intensively managed farm in the mid-western plain and in working horses at two locations in central plains of the state. The resistant allele (r) frequency in cyathostomins was significantly higher (p<0.05) in Vindhyan and Tarai and Bhabar zones of Uttar Pradesh. The prevalence of benzimidazole resistant allele (r) was significantly higher (p<0.05) in cyathostomins of intensively managed horses (allelic frequency-0.35) as compared to extensively managed horses (allelic frequency-0.22). The widespread prevalence of benzimidazole resistant alleles in equine cyathostomins in Uttar Pradesh, India, necessitates immediate replacement of the drugs of benzimidazole group with other unrelated effective anthelmintics for management and control of equine cyathostomins. Copyright © 2016 Elsevier B.V. All rights reserved.
Barsties, Lisa S; Walsh, Sophie D; Huijts, Tim; Bendtsen, Pernille; Molcho, Michal; Buijs, Thomas; Vieno, Alessio; Elgar, Frank J; Stevens, Gonneke W J M
2017-11-01
This internationally comparative study examines differences in alcohol consumption between first- and second-generation immigrant and native adolescents. We also investigate to what extent origin and receiving country alcohol per capita consumption (APCC) rates and proportions of heavy episodic drinkers (HED) are associated with immigrant adolescents' alcohol consumption. We used cross-sectional survey data from the 2013/2014 Health Behaviour in School-aged Children study. Applying multilevel regression analyses, we investigated the lifetime frequency of alcohol use and drunkenness in 69 842 13- to 15-year-olds in 23 receiving countries, with immigrants from over 130 origin countries (82% natives, 6% first-generation immigrants and 12% second-generation immigrants). The lifetime frequency of alcohol use was higher among natives than among first- and second-generation immigrants, while no differences were found between the latter two. Lifetime drunkenness was more frequent among first-generation immigrants than among natives and second-generation immigrants. Higher origin country APCC and HED were associated with more frequent lifetime alcohol use and drunkenness among immigrant adolescents. Cross-level interactions revealed that for lifetime frequency of alcohol use, the origin country HED effects were stronger for first- than for second-generation immigrant adolescents. Further, especially for first-generation immigrants, a higher receiving country HED was related to lower lifetime frequencies of alcohol use and drunkenness. Our results suggest differences in lifetime frequencies of alcohol use and drunkenness between natives and first- and second-generation immigrant adolescents. Origin country APCC and HED seem to affect immigrant adolescents' alcohol consumption differently than receiving country APCC and HED. © 2017 Australasian Professional Society on Alcohol and other Drugs.
Peltzer, Karl
2010-12-01
Physical inactivity leads to higher morbidity and mortality from chronic non-communicable diseases. In high income countries, studies have measured school population level physical activity and substance use, but comparable data are lacking from most African countries. To study the relationship between self-reported leisure time physical activity frequency and sedentary behavior and alcohol, tobacco, and other drug use behaviors among school children. A cross-sectional survey was conducted with the total sample of 24,593 school children aged 13 to 15 years from nationally representative samples from eight African countries. Univariate and multivariate analyses were conducted to assess the relationship between physical activity frequency, six measures of alcohol, tobacco, and other drug use, socioeconomic status, and mental health variables. In all, only 14.2% of the school children were frequently physically active (5 days and more in a week, at least 60 min/day) during leisure time; this was significantly higher among boys than girls. Ugandan and Kenyan school children were most physically active (17.7% and 16.0%, respectively), and Zambian and Senegalese the least (9.0% and 10.9%, respectively). Frequency of alcohol consumption and higher socioeconomic status were significantly associated with leisure time physical activity, while tobacco, illicit drug use, and mental health variables were not. Leisure time sedentary behavior of five and more hours spent sitting on a usual day were highly associated with all substance use variables. These findings suggest that leisure time physical activity frequency is associated with frequency of alcohol use and not with tobacco and illicit drug use, and leisure time sedentary behavior is highly associated with alcohol, tobacco, and drug use among adolescents.
A practical, low-noise coil system for magnetotellurics
Stanley, William D.; Tinkler, Richard D.
1983-01-01
Magnetotellurics is a geophysical technique which was developed by Cagnaird (1953) and Tikhonov (1950) and later refined by other scientists worldwide. The technique is a method of electromagnetic sounding of the Earth and is based upon the skin depth effect in conductive media. The electric and magnetic fields arising from natural sources are measured at the surface of the earth over broad frequency bands. An excellent review of the technique is provided in the paper by Vozoff (1972). The sources of the natural fields are found in two basic mechanisms. At frequencies above a few hertz, most of the energy arises from lightning in thunderstorm belts around the equatorial regions. This energy is propagated in a wave-guide formed by the earthionospheric cavity. Energy levels are higher at fundamental modes for this cavity, but sufficient energy exists over most of the audio range to be useful for sounding at these frequencies, in which case the technique is generally referred to as audio-magnetotellurics or AMT. At frequencies lower than audio, and in general below 1 Hz, the source of naturally occuring electromagnetic energy is found in ionospheric currents. Current systems flowing in the ionosphere generate EM waves which can be used in sounding of the earth. These fields generate a relatively complete spectrum of electromagnetic energy that extends from around 1 Hz to periods of one day. Figure 1 shows an amplitude spectrum characteristic of both the ionospheric and lightning sources, covering a frequency range from 0.0001 Hz to 1000 Hz. It can be seen that there is a minimum in signal levels that occurs at about 1 Hz, in the gap between the two sources, and that signal level increases with a decrease in frequency.
Maruyama, Koutatsu; Iso, Hiroyasu; Ito, Yoshinori; Watanabe, Yoshiyuki; Inaba, Yutaka; Tajima, Kazuo; Nakachi, Kei; Tamakoshi, Akiko
2009-12-01
No observational study has examined whether cancer-related biomarkers are associated with diet in Japanese. We therefore assessed sex-specific food and nutrient intakes according to serum IGF-I, IGF-II, IGFBP-3, TGF-b1, total SOD activity and sFas levels, under a cross-sectional study of 10,350 control subjects who answered the food frequency questionnaire in the first-wave nested case-control study within the Japan Collaborative Cohort Study. For both men and women, IGF-I levels were associated with higher intakes of milk, fruits, green tea, calcium and vitamin C. IGF-II levels were associated with higher intakes of milk, yogurt, fruits and miso soup, and lower intakes of rice, coffee and carbohydrate. IGFBP-3 levels were associated with higher intakes of milk, yogurt, fruits and vitamin C, and lower intakes of rice, energy, protein, carbohydrate, sodium and polyunsaturated fatty acids. TGF-b1 levels were associated with lower intakes of coffee intakes, and higher intakes of miso soup and sodium. Total SOD activity levels were associated with lower intakes of most nutrients other than energy, carbohydrate, iron, copper, manganese, retinol equivalents, vitamin A, B2, B12, niacin, folic acid, vitamin C and fish fat. sFas levels were associated with higher intakes of manganese and folic acids. The results of the present study should help to account for findings on those biomarkers regarding risks of cancer and other lifestyle-related diseases in terms of dietary confounding as causality.
The very low frequency power spectrum of Centaurus X-3
NASA Technical Reports Server (NTRS)
Gruber, D. E.
1988-01-01
The long-term variability of Cen X-3 on time scales ranging from days to years has been examined by combining data obtained by the HEAO 1 A-4 instrument with data from Vela 5B. A simple interpretation of the data is made in terms of the standard alpha-disk model of accretion disk structure and dynamics. Assuming that the low-frequency variance represents the inherent variability of the mass transfer from the companion, the decline in power at higher frequencies results from the leveling of radial structure in the accretion disk through viscous mixing. The shape of the observed power spectrum is shown to be in excellent agreement with a calculation based on a simplified form of this model. The observed low-frequency power spectrum of Cen X-3 is consistent with a disk in which viscous mixing occurs about as rapidly as possible and on the largest scale possible.
Deviations from LTE in a stellar atmosphere
NASA Technical Reports Server (NTRS)
Kalkofen, W.; Klein, R. I.; Stein, R. F.
1979-01-01
Deviations for LTE are investigated in an atmosphere of hydrogen atoms with one bound level, satisfying the equations of radiative, hydrostatic, and statistical equilibrium. The departure coefficient and the kinetic temperature as functions of the frequency dependence of the radiative cross section are studied analytically and numerically. Near the outer boundary of the atmosphere, the departure coefficient is smaller than unity when the radiative cross section grows with frequency faster than with the square of frequency; it exceeds unity otherwise. Far from the boundary the departure coefficient tends to exceed unity for any frequency dependence of the radiative cross section. Overpopulation always implies that the kinetic temperature in the statistical-equilibrium atmosphere is higher than the temperature in the corresponding LTE atmosphere. Upper and lower bounds on the kinetic temperature are given for an atmosphere with deviations from LTE only in the optically shallow layers when the emergent intensity can be described by a radiation temperature.
Aircraft interior noise reduction by alternate resonance tuning
NASA Technical Reports Server (NTRS)
Bliss, Donald B.; Gottwald, James A.; Srinivasan, Ramakrishna; Gustaveson, Mark B.
1990-01-01
Existing interior noise reduction techniques for aircraft fuselages perform reasonably well at higher frequencies, but are inadequate at lower frequencies, particularly with respect to the low blade passage harmonics with high forcing levels found in propeller aircraft. A method is being studied which considers aircraft fuselage lined with panels alternately tuned to frequencies above and below the frequency that must be attenuated. Adjacent panels would oscillate at equal amplitude, to give equal source strength, but with opposite phase. Provided these adjacent panels are acoustically compact, the resulting cancellation causes the interior acoustic modes to become cutoff, and therefore be non-propagating and evanescent. This interior noise reduction method, called Alternate Resonance Tuning (ART), is currently being investigated both theoretically and experimentally. This new concept has potential application to reducing interior noise due to the propellers in advanced turboprop aircraft as well as for existing aircraft configurations.
Osadchuk, L V; Popova, A V; Erkovich, A A; Voroshilova, N A; Osadchuk, A V
2017-09-01
Smoking and alcohol consumption remain widespread throughout the world, including Russia. Recently, due to the increase in male infertility and subfertility, special attention has been paid to the effects of smoking and alcohol on the reproductive health of young men. The aim of this study was to assess the effects of smoking and moderate alcohol consumption on spermatogenesis, reproductive hormone levels and metabolic status in young men living in Western Siberia (Novosibirsk). One hundred thirty-three volunteers (mean age 21.1+/-0.3 years) were tested for the sperm concentration, the proportion of mobile and morphologically normal spermatozoa in the ejaculate, blood serum levels of follicle-stimulating and luteinizing hormones, prolactin, testosterone, estradiol, inhibin B, triglycerides, total cholesterol, high and low density lipoprotein cholesterol, glucose and uric acid. and conclusions The studied lifestyle factors were found to have no effects on spermatogenesis. Smoking more than 10 cigarettes per day and a moderate frequency of alcohol consumption (up to 1 time per week) was associated with higher blood serum testosterone levels and engaging in more frequent sexual contacts compared to non-smoking and non-drinking men. Drinking alcohol more than once a week and smoking more than 8 cigarettes per day was associated, along with the increase in testosterone levels and the frequency of sexual contacts, with lower levels of follicle-stimulating hormone and higher serum triglyceride levels. Thus, in young men, frequent drinking and smoking can alter the hormonal and metabolic balance, which, as the duration of the exposure and the strength of the factors increase, will increase the risk of reproductive disorders.
NASA Astrophysics Data System (ADS)
Kumar, Ajay; Tripathi, M. M.; Chaujar, Rishu
2018-04-01
In this work, a comprehensive analog and RF performance of a novel Black Phosphorus-Junctionless-Recessed Channel (BP-JL-RC) MOSFET has been explored at 45 nm technology node (Gate length = 20 nm). The integration of black phosphorus with junctionless recessed channel MOSFET, leads to higher drain current of about 0.3 mA and excellent switching ratio (of the order of 1011) due to reduced off-current which leads to improvement in sub-threshold slope (SS) (67mV/dec). Further, RF performance metrics have also been studied with an aim to analyze high-frequency performance. The following FOMs have been evaluated: cut-off frequency (fT), maximum oscillator frequency (fMAX), stern stability factor, various power gains and parasitic capacitances at THz frequency range. Thus, in addition to the high packing density offered by RC MOSFET, the proposed design finds numerous application at THz frequency making it a promising candidate at wafer scale integration level.
NASA Astrophysics Data System (ADS)
Ebrahimi Orimi, H.; Esmaeili, M.; Refahi Oskouei, A.; Mirhadizadehd, S. A.; Tse, P. W.
2017-10-01
Condition monitoring of rotary devices such as helical gears is an issue of great significance in industrial projects. This paper introduces a feature extraction method for gear fault diagnosis using wavelet packet due to its higher frequency resolution. During this investigation, the mother wavelet Daubechies 10 (Db-10) was applied to calculate the coefficient entropy of each frequency band of 5th level (32 frequency bands) as features. In this study, the peak value of the signal entropies was selected as applicable features in order to improve frequency band differentiation and reduce feature vectors' dimension. Feature extraction is followed by the fusion network where four different structured multi-layer perceptron networks are trained to classify the recorded signals (healthy/faulty). The robustness of fusion network outputs is greater compared to perceptron networks. The results provided by the fusion network indicate a classification of 98.88 and 97.95% for healthy and faulty classes, respectively.
Dieleman, Gwendolyn C; Huizink, Anja C; Tulen, Joke H M; Utens, Elisabeth M W J; Creemers, Hanneke E; van der Ende, Jan; Verhulst, Frank C
2015-01-01
It is of debate whether or not childhood anxiety disorders (AD) can be captured by one taxonomic construct. This study examined whether perceived arousal (PA), autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis measures can distinguish children with different primary diagnoses of clinical anxiety disorders (AD) from each other, and from a general population reference group (GP). The study sample consisted of 152 AD children (comparing separation anxiety disorder, generalized anxiety disorder, social phobia and specific phobia), aged 8- to 12-years, and 200 same-aged reference children. HPA-axis functioning was measured by a diurnal cortisol profile. ANS functioning was measured by continuous measures of skin conductance level in rest and during a mental arithmetic task and high frequency heart rate variability in rest. PA was assessed by a questionnaire. The AD sample showed lower high frequency heart rate variability during rest, heightened anticipatory PA, higher basal and reactive skin conductance levels and lower basal HPA-axis functioning compared to the GP sample. The existence of three or more clinical disorders, i.e. a high clinical 'load', was associated with lower basal HPA-axis functioning, higher skin conductance level and lower posttest PA. Specific phobia could be discerned from social phobia and separation anxiety disorder on higher skin conductance level. Our findings indicated that children with AD have specific psychophysiological characteristics, which resemble the psychophysiological characteristics of chronic stress. A high clinical 'load' is associated with an altered ANS and HPA-axis functioning. Overall, ANS and HPA-axis functioning relate to AD in general, accept for specific phobia. Copyright © 2014 Elsevier Ltd. All rights reserved.
Frequency and significance of parvovirus B19 infection in patients with rheumatoid arthritis.
Naciute, Milda; Mieliauskaite, Diana; Rugiene, Rita; Nikitenkiene, Rita; Jancoriene, Ligita; Mauricas, Mykolas; Nora-Krukle, Zaiga; Murovska, Modra; Girkontaite, Irute
2016-12-01
The present study aims to clarify the possible involvement of parvovirus B19 (B19V) infection in rheumatoid arthritis (RA) pathogenesis by investigating the presence of B19V infection markers (genomic sequences and virus-specific antibodies) in association with the level of cytokines and RA clinical activity and aggressiveness. A total of 118 RA patients and 49 age- and sex-matched healthy volunteers were enrolled in the study. Nested PCR was used to detect B19V sequences in whole blood and cell-free plasma DNA, ELISA to detect virus-specific antibodies and cytokine levels in plasma and recomLine dot blot assay for antibodies to separate B19V antigens. The detection frequency of B19V DNA was higher in patients with RA (25.4 %) in comparison with healthy persons (18.4 %). B19V DNA in cell-free plasma (B19+p) was detected significantly often in RA patients in comparison with healthy controls (13.6 vs 2 %; P=0.0002). RA B19+p patients had higher disease activity and aggressiveness, decreased haemoglobin and increased erythrocyte sedimentation rates. IL-6 plasma levels were significantly higher in RA patients than in controls. Within the RA patients' group the IL-6 level was significantly increased in B19+p patients with disease activity scores of DAS28>5.2, high C-reactive protein and low haemoglobin. Contrary to the healthy controls, the majority of RA B19+p patients did not have antibodies to VP-1S (VP1u) and VP-N (N-terminal half of structural proteins VP1 and VP2), which correspond to the epitopes of neutralizing antibodies. These results indicate that B19V infection at least in some patients is involved in RA pathogenesis.
Interactions of Sexual Activity, Gender, and Depression with Immunity
Lorenz, Tierney; van Anders, Sari
2015-01-01
Introduction Depression can suppress immune function, leading to lower resistance against infection and longer healing times in depressed individuals. Sexuality may also influence immune function, with evidence that sexual activity is associated with lowered immune function in women and mixed results in men. Immune mediators like immunoglobulin A (IgA) are immediately relevant to sexual health, since they are the first line of defense against pathogens at mucous membranes like the vagina. Aim This study aims to determine if and how depression, sexual activity, and their interaction impact salivary IgA (SIgA) in men and women. Methods In Study 1, a community-based sample of 84 women and 88 men provided saliva samples and completed questionnaires on their demographic background, level of depression, and frequency of partnered and solitary sexual activity. Study 2, conducted separately in an undergraduate student sample of 54 women and 52 men, had similar methods. Main Outcome Measures The main outcome measures were scores on the General Well-Being Schedule depression subscale, reported frequency of sexual activity, and SIgA levels as measured by enzyme immunoassay. Results Across studies, higher levels of partnered sexual activity were associated with lower SIgA for women with high depression scores, but not for women with low depression scores. In contrast, higher levels of partnered sexual activity were associated with higher SIgA for men with high depression scores, but not for men with low depression scores. Conclusion Our results show that partnered sexual activity is a risk factor for lowered immunity in women with depressive symptoms but a possible resilience factor for men with depressive symptoms. This suggests a role for sexual activity in determining the impact of depression on physical health parameters. PMID:23448297
Color-motion feature-binding errors are mediated by a higher-order chromatic representation.
Shevell, Steven K; Wang, Wei
2016-03-01
Peripheral and central moving objects of the same color may be perceived to move in the same direction even though peripheral objects have a different true direction of motion [Nature429, 262 (2004)10.1038/429262a]. The perceived, illusory direction of peripheral motion is a color-motion feature-binding error. Recent work shows that such binding errors occur even without an exact color match between central and peripheral objects, and, moreover, the frequency of the binding errors in the periphery declines as the chromatic difference increases between the central and peripheral objects [J. Opt. Soc. Am. A31, A60 (2014)JOAOD60740-323210.1364/JOSAA.31.000A60]. This change in the frequency of binding errors with the chromatic difference raises the general question of the chromatic representation from which the difference is determined. Here, basic properties of the chromatic representation are tested to discover whether it depends on independent chromatic differences on the l and the s cardinal axes or, alternatively, on a more specific higher-order chromatic representation. Experimental tests compared the rate of feature-binding errors when the central and peripheral colors had the identical s chromaticity (so zero difference in s) and a fixed magnitude of l difference, while varying the identical s level in center and periphery (thus always keeping the s difference at zero). A chromatic representation based on independent l and s differences would result in the same frequency of color-motion binding errors at everyslevel. The results are contrary to this prediction, thus showing that the chromatic representation at the level of color-motion feature binding depends on a higher-order chromatic mechanism.
Polymorphisms in the glutathione pathway modulate cystic fibrosis severity: a cross-sectional study
2014-01-01
Background Cystic fibrosis (CF) clinically manifests with various levels of severity, which are thought to be modulated by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR), modifier genes, and the environment. This study verified whether polymorphisms in modifier genes associated with glutathione (GSH) metabolism influence CF severity. Methods A cross-sectional study of 180 CF patients was carried out from 2011 to 2012. We analyzed CFTR mutations, polymorphisms (GSTM1 and GSTT1 deletions, GSTP1 + 313A > G, GCLC-129C > T, and GCLC-3506A > G) in modifier genes and CF clinical severity as assessed by 28 clinical and laboratory variables. Results Significant associations were found between modifier gene polymorphisms and particular phenotypes or genotype changes. These included GCLC-129C > T with a higher frequency of the Pseudomonas aeruginosa mucoid to CC genotype (p = 0.044), and GCLC-3506A > G with a higher frequency of the no-mucoid P. aeruginosa (NMPA) to AA genotype (p = 0.012). The GSTT1 deletion was associated with a higher frequency of the NMPA to homozygous deletion (p = 0.008), GSTP1 + 313A > G with a minor risk of osteoporosis (p = 0.036), and patient age ≤ 154 months (p = 0.044) with the AA genotype. The Bhalla score was associated with GCLC-3506A > G (p = 0.044) and GSTM1/GSTT1 deletion polymorphisms (p = 0.02), while transcutaneous hemoglobin oxygen saturation levels were associated with GSTT1 deletions (p = 0.048). Conclusion CF severity is associated with polymorphisms in GSH pathways and CFTR mutations. PMID:24593045