An Optical Measuring Transducer for a Micro-Opto-Electro-Mechanical Micro-g Accelerometer Based on the Optical Tunneling Effect.

Micro-opto-electro-mechanical (MOEM) accelerometers that can measure small accelerations are attracting growing attention thanks to their considerable advantages-such as high sensitivity and immunity to electromagnetic noise-over their rivals. In this treatise, we analyze 12 schemes of MOEM-accelerometers, which include a spring mass and a tunneling-effect-based optical sensing system containing an optical directional coupler consisting of a fixed and a movable waveguide separated by an air gap. The movable waveguide can perform linear and angular movement. In addition, the waveguides can lie in single or different planes. Under acceleration, the schemes feature the following changes to the optical system: gap, coupling length, overlapping area between the movable and fixed waveguides. The schemes with altering coupling lengths feature the lowest sensitivity, yet possess a virtually unlimited dynamic range, which makes them comparable to capacitive transducers. The sensitivity of the scheme depends on the coupling length and amounts to 11.25 × 103 m-1 for a coupling length of 44 µm and 30 × 103 m-1 for a coupling length of 15 µm. The schemes with changing overlapping areas possess moderate sensitivity (1.25 × 106 m-1). The highest sensitivity (above 6.25 × 106 m-1) belongs to the schemes with an altering gap between the waveguides.

Point-wise variability of threshold sensitivity of 24-2 and 10-2 visual fields.

PURPOSE: To evaluate point-wise variability of threshold sensitivity at different test locations on 24-2 and 10-2 visual field (VF). MATERIALS AND METHODS: Electronic medical records of patients seen at a tertiary eye care center were screened to include those with at least 3 reliable VF with glaucomatous defects involving fixation on 24-2 and confirmed on 10-2 test strategy. Ninety eyes of 90 patients were categorized into 3 severity groups based on mean deviation (MD on 24-2) test strategy; MD<-6 dB and >-12 dB, <-12 dB and >-20 dB and <-20 dB and >-30 dB. Variability of threshold sensitivity at all topographical test locations in central (ring 1), mid-peripheral (ring 2), peripheral rings on 24-2 VF test strategy (ring 3), and central (ring 4) and paracentral (ring 5) on 10-2 VF test along with variability of visual field index and central field index were calculated by multilevel mixed effects model. RESULTS: Central ring1 on 24-2 and ring 4 on 10-2 showed higher variability (>10 dB) than peripheral ring 2, 3, and 5. Seventy-three eyes were adjudged as stable and 17 as progressing in this cohort. The average ring and point-wise variability was higher in stable eyes (2-6 dB) across all glaucoma severities. Across severity, variability was seen to decrease with increasing severity with minimal variability in point-wise threshold sensitivity beyond MD <-20 dB. CONCLUSION: Central test points/ring on 24-2 and 10-2 with greater threshold variability suggests that status of the eye, severity and topographical location of test points should be incorporated into conventional progression algorithms to predict true glaucoma progression.

The basophil activation test differentiates between patients with alpha-gal syndrome and asymptomatic alpha-gal sensitization.

BACKGROUND: Galactose-alpha-1,3-galactose (alpha-gal) syndrome is characterized by the presence of serum specific IgE antibodies to alpha-gal and delayed type I allergic reactions to the carbohydrate alpha-gal after consumption of mammalian (red) meat products and drugs of mammalian origin. Diagnostics currently rely on patient history, skin tests, determination of serum specific IgE antibodies, and oral food or drug challenges. OBJECTIVE: We sought to assess the utility of different basophil parameters (basophil reactivity and sensitivity, the ratio of the percentage of CD63+ basophils induced by the alpha-gal-containing allergen to the percentage of CD63+ basophils after stimulation with anti-FcεRI antibody [%CD63+/anti-FcεRI], and area under the dose-response curve [AUC]) as biomarkers for the clinical outcome of patients with alpha-gal syndrome compared with subjects with asymptomatic alpha-gal sensitization. METHODS: In addition to routine diagnostics, a basophil activation test (Flow CAST) with different concentrations of alpha-gal-containing allergens (eg, commercially available alpha-gal-carrying proteins and pork kidney extracts) was performed in 21 patients with alpha-gal syndrome, 12 alpha-gal-sensitized subjects, and 18 control subjects. RESULTS: Alpha-gal-containing allergens induced strong basophil activation in a dose-dependent manner in patients. Basophil reactivity at distinct allergen concentrations, the %CD63+/anti-FcεRI ratio across most allergen concentrations, the AUC of dose-response curves, and basophil allergen threshold sensitivity (CD-sens) with pork kidney extract were significantly higher in patients with alpha-gal syndrome compared with those in sensitized subjects. All parameters were negative in control subjects. CONCLUSION: The basophil activation test should be considered as an additional diagnostic test before performing time-consuming and potentially risky oral provocation tests. The %CD63+/anti-FcεRI ratio for all allergens and AUCs for pork kidney were the best parameters for distinguishing patients with alpha-gal syndrome from subjects with asymptomatic alpha-gal sensitization.

Higher Tactile Temporal Resolution as a Basis of Hypersensitivity in Individuals with Autism Spectrum Disorder.

Many individuals with autism spectrum disorder (ASD) have symptoms of sensory hypersensitivity. Several studies have shown high individual variations in temporal processing of tactile stimuli. We hypothesized that these individual differences are linked to differences in hyper-reactivity among individuals with ASD. Participants performed two tasks as to vibrotactile stimuli: One is a temporal order judgement task, and another is a detection task. We found that individuals with ASD with higher temporal resolution tended to have more severe hypersensitivity symptoms. In contrast, the tactile detection threshold/sensitivity were related to the severities of stereotyped behaviour and restricted interests, rather than to hypersensitivity. Our findings demonstrate that higher temporal resolution to sensory stimuli may contribute to sensory hypersensitivity in individuals with ASD.

Basophil biomarkers as useful predictors for sublingual immunotherapy in allergic rhinitis.

Prevalence of allergic diseases is increasing worldwide. Allergen-specific immunotherapy (ASIT) is potentially the only curative treatment for allergy, but there is a lack of reliable methods to monitor the immune responses to ASIT and to predict clinical efficacy. Recently, the definition of allergen sensitivity threshold (CD-Sens) by Basophil Activation Tests has been suggested as potential method in this context. The aim of this study was to compare trends of CD-Sens, measured by the markers CD63 and CD203c, and clinical symptoms in subjects with allergic rhinitis receiving Sublingual Immunotherapy (SLIT). 26 rhinitis patients allergic to Parietaria were selected and matched into two groups; a SLIT treated group (SG) and a reference group (RG) treated by traditional anti-allergic medications. Visual Analogue Scale (VAS) score for the four cardinal symptoms of rhinitis and peripheral blood was collected before the first dose of SLIT (T0) and after 12 months (T12) to define the severity of the symptoms and the sensitivity of basophils to Parietaria. The comparison between T0 and T12 in SG patients showed a significant decrease of symptom severity (VAS score) and an increased tolerability of basophils to Parietaria (CD-Sens) both by CD63 and CD203c. But, only CD203c seems to be correlated with the clinical symptoms. These data corroborate the hypothesis that SLIT could change the immunological course of allergic sensitization already in the first year, and that an immunological parameter as CD-Sens measured by CD63 and CD203c expression on stimulated basophils could be useful to monitor the changes in the immune system.

Quantitative Analysis of Changes of Automated Perimetric Thresholds after Pupillary Dilation and induced Myopia in Normal Subjects

We quantitatively analyzed the changes of the(retinal) threshold sensitivities between normal status and dilated emmetropic status, and between dilated emmetropic status and -1.0D induced myopic status. Three consecutive visual field examinations by Humphrey Field Analyzer C-30-2 threshold test and STATPAC program were performed in 36 eyes of 21 normal subjects who ranged in age from 23 to 40 years. The results were as follows: 1) There was a statistically significant decrease (0.87 +/- 0.91dB) in the mean threshold sensitivity within the central 30 degrees at the dilated emmetropic status(27.90dB) as compared with the normal status(28.77dB) (p=0.0001). 2) There was a statistically significant decrease(0.99 +/- 0.61dB) at -1.0D induced myopic status(26.91dB) as compared with the dilated emmetropic status(27.90dB) (p=0.0001). 3) After dilation, the mean threshold sensitivity between 20 and 30 degrees of field showed statistically significant decrease as compared with thosE' within the central 20 degrees of visual field(p0.05). Therefore, we emphasize the importance of consistent pupillary size and correct refractive state in performing the serial automated visual field tests.

Quantitative analysis of changes of automated perimetric thresholds after pupillary dilation and induced myopia in normal subjects

We quantitatively analyzed the changes of the (retinal) threshold sensitivities between normal status and dilated emmetropic status, and between dilated emmetropic status and -1.0D induced myopic status. Three consecutive visual field examinations by Humphrey Field Analyzer C-30-2 threshold test and STATPAC program were performed in 36 eyes of 21 normal subjects who ranged in age from 23 to 40 years. The results were as follows: 1) There was a statistically significant decrease (0.87 +/- 0.91dB)in the mean threshold sensitivity within the central 30 degrees at the dilated emmetropic status (27.90dB) as compared with the normal status (28.77dB)(p = 0.0001). 2) There was a statistically significant decrease(0.99 +/- 0.61dB) at -1.0D induced myopic status(26.91dB) as compared with the dilated emmetropic status(27.90dB)(p = 0.0001). 3) After dilation, the mean threshold sensitivity between 20 and 30 degrees of field showed statistically significant decrease as compared with those within the central 20 degrees of visual field(p 0.05). Therefore, we emphasize the importance of consistent pupillary size and correct refractive state in performing the serial automated visual field tests.