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This report proposes a quasi-optical millimeter-wave system based on a noninvasive measurement technique to diagnose high-density plasmas. The millimeter wave in the F-band (90–140 GHz) can interact with high-density plasma (1013–1014 cm−3) in the quasi-optical system, such that the plasma characteristics (e.g., plasma density and effective collision frequency) obtained using the Drude model can be measured with a high signal-to-noise ratio. High-density inductive radio frequency (RF) discharge argon plasma is generated in a helix of inductively coupled plasma using RF power of up to 1000 W at 13.56 MHz with a pressure of a few Torr. The millimeter-wave signals can be analyzed to estimate the plasma-density distribution by using the proposed axisymmetric 2-D multilayered plasma modeling. The experimental results agreed well with the model calculations. Qualitatively, the plasma density tends to increase with increasing RF power and gas pressure. The effective collision frequency decreases only with increasing gas pressure. The proposed measurement technique will also be applicable to measuring localized regions (with areas of a few square millimeters) of higher density plasma (1014–1017 cm−3) by using terahertz waves for various applications.

Background: To evaluate the normative values of corneal endothelial cell parameters within a group of healthy young Egyptian adults using specular microscopy and to examine any correlations between endothelial parameters and refractive or biometric parameters. Methods: In this cross-sectional study, specular microscopy was used to study the right eyes of 150 healthy young volunteers and evaluated endothelial cell parameters, including cellular density, hexagonality (HEX), and coefficient of variation (CV) at 15 different points on the back corneal surface, which were later grouped into the central zone and either four quadrants or three annular zones. The same eyes underwent refractive and biometric assessments. Results: Hundred fifty healthy adults were examined, and the age ranged from 20 to 30 years, with a median of 23 (interquartile range, 21–27) years. The mean ± standard deviation of central cell density was 2902.7 ± 270.7 cells/square millimeter. The superior paracentral area had the lowest mean density (2895.8 cells/square millimeter), but the highest mean HEX (67.7%), while the inferior peripheral area had the highest mean density (3100.5 cells/square millimeter) but the lowest mean HEX (64%). The difference in cell density among the three annular zones was not statistically significant (P = 0.365). However, HEX and CV in the central and paracentral zones differed statistically significantly from those of the peripheral zone (P < 0.001 and P = 0.014, respectively). Weak but non-significant correlations were detected between endothelial cell density and all measured refractive and biometric parameters. Conclusions: The findings of this study provided useful normative biometric and specular data in a specific age group and a specific population, and could be useful in planning intraocular surgery in young Egyptian adults. However, future longitudinal studies with a larger sample could refine more endothelial cell parameter specifications over time.

In this talk, I will give an overview of our research efforts on developing InP/InAsP nanowire (NW) heterostructure photodetectors for NIR-LWIR detection. I will discuss design, modeling, growth, device processing and optoelectronic properties of both single NW devices and large square millimeter devices comprising millions of NWs connected in parallel. The developed device family includes p-i-n and SAM avalanche diodes, as well as state-of-the-art photoconductors with embedded quantum discs. I will discuss a newly developed model that unravels the high, non-linear optical gain observed in photoconductors that stems from complex carrier dynamics involving multiple traps on the surface of the NWs. I will also briefly introduce our recently initiated efforts on realizing bias-tunable detectors with NW arrays embedded in designed photonic crystals for spectral tuning of optical modes.

A millimeter-sized on-chip antenna is presented. The antenna is composed of two loops, and the impedance of the antenna can be adapted by modifying the shape of one loop without altering antenna gain. The proposed antenna was matched to different rectifier circuits at the 5.8 GHz and 24 GHz frequencies, and achieved a gain of -23.7 dBi and -13.3 dBi respectively. The antenna was tested at 5.8 GHz in conjunction with a low-power RFID circuit and enough power was supplied for the circuit to function at a distance of 7 cm from the power supply.

Here, we introduce a novel parallel binary-weighed digital-to-analog converter on a silicon photonic integrated platform with a sample efficiency exceeding 120 G-samples per second. And an about 1 square millimeter footprint.

Sensor technology is one of the three pillars of information technology. This paper aims to discuss the problems of insensitive detection, poor stability, and uncomfortable wearing of sensors in the fields of human–computer interaction, 5G communication, and medical detection. A sensing unit with a microstructured flexible sensing front end is a cone-like structure with a single size of 18–22 μm. They are evenly distributed and can reach 2500 units per square millimeter. In the pressure range, the sensitivity of the sensor unit is 0.6 KPa−1 (no microstructure sensitivity at 0.15 KPa−1), and the response time is fast (

In the thermal analysis of a Modular Multilevel Converter (MMC) system, one of the challenges is to model the heat sources and thermal paths across large spatial scales, i.e., from a tiny power semiconductor chip at square millimeters to the whole converter system up to several thousand cubic meters. Without good understanding of the dissimilarity of thermal behaviors under different spatial scales, conventional thermal models usually lead to either considerable modeling errors or heavy computational burden. In this paper, a hierarchical decomposition method is proposed to do the system-level thermal modeling of the MMC. At Sub-Module(SM) level, ethe junction/hotspot-to-local ambient thermal model of devices is established, where Thermal Cross-Coupling (TCC) effects among different devices in the SM are considered. At converter-level, thermal model is obtained to depict mutual European influences Unionamong the SMs in the MMC. A 15-kVA MMC prototype provides the experimental verifications at last.

The indirect time-of-flight principle is one possibility to build a three-dimensional (3D) camera system. Available products based on this principle mostly use special CMOS sensors for demodulation of the optical signal at the receiver. This special CMOS chip can be replaced by a standard image sensor in combination with a quantum well electroabsorption modulator. In this case, the modulator heavily influences the 3D camera performance. Especially the characteristics of large-area devices are of major interest. Transmission electroaborption modulators with sizes in the square millimeter range have been fabricated for operating wavelengths of 850 and 940 nm. While the 850nm devices were realized as non-resonant structures, for 940nm devices a resonant design was developed to overcome the limitation in the number of quantum wells. Investigations of the static and dynamic behavior show extinction ratios up to 2.5 dB and corner frequencies up to 30 MHz. A single-point distance measurement setup demonstrates the high potential of the devices for the 3D application.

Objectives: The hierarchical structure of enamel gives insight on the properties of enamel and can influence its strength and ultimately caries experience. Currently, past caries experience is quantified using the decayed, missing, filled teeth/decayed, missing, filled surface (DMFT/DMFS for permanent teeth, dmft/dmfs for primary teeth), or international caries detection and assessment system (ICDAS) scores. By analyzing the structure of enamel, a new measurement can be utilized clinically to predict susceptibility to future caries experience based on a patient&rsquo, s individual&rsquo, s biomarkers. The purpose of this study was to test the hypothesis that number of prisms by square millimeter in enamel and average gap distance between prisms and interprismatic areas, influence caries experience through genetic variation of the genes involved in enamel formation. Materials and Methods: Scanning electron microscopy (SEM) images of enamel from primary teeth were used to measure (i) number of prisms by square millimeter and interprismatic spaces, (ii) prism density, and (iii) gap distances between prisms in the enamel samples. The measurements were tested to explore a genetic association with variants of selected genes and correlations with caries experience based on the individual&rsquo, s DMFT+ dmft score and enamel microhardness at baseline, after an artificial lesion was created and after the artificial lesion was treated with fluoride. Results: Associations were found between variants of genes including ameloblastin, amelogenin, enamelin, tuftelin, tuftelin interactive protein 11, beta defensin 1, matrix metallopeptidase 20 and enamel structure variables measured (number of prisms by square millimeter in enamel and average gap distance between prisms and interprismatic areas). Significant correlations were found between caries experience and microhardness and enamel structure. Negative correlations were found between number of prisms by square millimeter and high caries experience (r value= &minus, 0.71), gap distance between prisms and the enamel microhardness after an artificial lesion was created (r value= &minus, 0.70), and gap distance between prisms and the enamel microhardness after an artificial lesion was created and then treated with fluoride (r value= &minus, 0.81). There was a positive correlation between number of prisms by square millimeter and prism density of the enamel (r value = 0.82). Conclusions: Our data support that genetic variation may impact enamel formation, and therefore influence susceptibility to dental caries and future caries experience. Clinical Relevance: The evaluation of enamel structure that may impact caries experience allows for hypothesizing that the identification of individuals at higher risk for dental caries and implementation of personalized preventative treatments may one day become a reality.

This paper presents an active RF phase shifter, targeted towards 5G wireless systems, which uses an IQ vector modulator (IQVM) topology with a 10 bit cartesian codebook. The circuit is designed using 45 nm CMOS SOI technology. To generate the I and Q basis vectors for the IQVM, a tunable polyphase filter with a novel tuning mechanism is used, which allows operation over an octave of a frequency range, from 22 GHz to 40 GHz. The RF bandwidth of the proposed phase shifter is 2.5 GHz and can provide in excess of 8 dB of fine gain control over 360 degrees of phase shift. Active area occupied is 0.2 square millimeter. The total DC power consumed from 1 V supply is 36 mW.

Square millimeters of free-standing graphene do not exist per se because of thermal fluctuations in two-dimensional crystals and their tendency to collapse during the detachment from the substrate. Here we form millimeter-scale freely suspended graphene by injecting an air bubble underneath a graphene monolayer floating at the water–air interface, which allowed us to measure the contact angle on fully free-standing non-contaminated graphene. A captive bubble measurement shows that free-standing clean graphene is hydrophilic with a contact angle of 42° ± 3°. The proposed design provides a simple tool to probe and explore the wettability of two-dimensional materials in free-standing geometries and will expand our perception of two-dimensional materials technologies from microscopic to now millimeter scales., Experimental determination of the contact angle of a two-dimensional film is crucial to understand its wettability characteristics. Here, the authors use the captive bubble method to estimate a contact angle value of 42° ± 3° for a monolayer graphene film.

Purpose To study the effects of different axial lengths on ultra-widefield imaging to determine the presence of distortion in images despite software correction and calculate an enlargement factor based on angular location. Design Experimental image analysis study. Study Objects Three 3-dimensional printed model eyes simulating eyes with axial lengths of 22, 24, and 26 mm. Each model has a grid of rings 9° apart centered at the posterior pole. Methods Single-center study performed at the National Institute for Health Research Moorfields Biomedical Research Centre (London, UK). Each model was imaged using Optos 200TX (Optos, Dunfermline, UK). Two images for each model eye that were corrected using V2 Vantage Pro software (Optos) were used for analysis and the average values obtained. Each image inter-ring area was measured using ImageJ to obtain a measured image area in pixel and square millimeters. This was compared with the true calculated object inter-ring area and an enlargement factor was determined. Main Outcome Measures Measured image inter-ring area in pixels and square millimeters. True calculated object inter-ring area in square millimeters. Results The enlargement factor of the rings gradually increases toward the periphery with factors of 1.4 at 45° and 1.9 at the equator. The axial lengths did not affect the enlargement factor of the rings imaged in 3 different model eyes (P = 0.9512). The anterior equator exhibits a significant distortion despite the software correction. Conclusion The enlargement factor depends on angular location and not axial length. The enlargement factors can be used in clinical practice to more accurately measure area in ultra-widefield imaging.

This paper presents the development of a digital maskless lithography process and its capabilities for micro-feature fabrication using biomachining as a metal removal process. The maskless lithography system was developed using a DLP projector and is used to fabricate arrays of micro-sized geometric features. Square shapes were produced in dimple and pillar modes, and the smallest widths were 60 and 50 μm, respectively. For line features, the smallest width of 35 μm was produced with a maximum gap of 60 μm. Micro-features with a high density of 140 dimples per square millimeter were also produced. Geometric dimple shapes were biomachined on iron, and tribology analysis was performed. The coefficients of friction were compared for workpieces with and without surface textures and for different dimple shapes.

Nanosecond speckle-modulated laser pulses were applied to fabricate nanotextured metal substrates for surface enhanced fluorescence (SEF) applications. The speckle-modulated patterns obtained by passing the laser nanosecond pulse through the simplest diffusive object were found suitable for fast large-scale texturing of metal films with micron-sized structures - nanojets, nanobumps and submicron through holes, previous reported only for single-shot nanoablation with tightly focused beams. The optimal regime for pattering the mm-scale areas of Au films with nanojets with an averaged recording density of 105 nanojets per square millimeter were determined and realized. The fabricated nanotextured Au substrates demonstrate spatially uniform SEF signal from the Rhodamine 6G organic dye with averaged 5-fold enhancement factor being compared with unmodified Au surface.

PURPOSE: To determine the feasibility, dissection accuracy, and endothelial viability of ultrathin endothelial lamellae harvested from organ-cultured corneas using a single-pass with an innovative motor-driven linear microkeratome system. METHODS: Forty-eight (n = 48) paired organ-cultured human corneas were randomly assigned to dissection (study eyes, n = 24) with fellow eyes serving as the control (fellow eyes, n = 24). After organ culture and deswelling in a medium containing 6% dextran, endothelial lamellae with a target thickness

We propose “the external reflectance versus height conversion (ERHC) method” for measuring the full-field three-dimensional surface topography of a sample height from one micron to 100 micrometers. It is similar to the camera method, capturing images reflected and/or not from a prism by using a lens and a CCD. The reflectance of a point in the image can be converted to the height of the point. The method can obtain large-area full-field real-time three-dimensional measurement results and has the advantages of simple operation, low cost, and easy assembly. The measurement area is in the range of a few square millimeters for each time. The lateral and vertical resolutions are 2 and 0.1 micrometers, respectively, and the error is about 1% compared with the confocal microscope.

This paper presents a report on the enhanced performance of an optimized metamaterial loaded square fractal antenna (OMSFA). The design and simulation of the antenna was carried out using Electronic Desk Top HFSS version 18.2 software. The antenna layer spreads over an area of 23 square millimeter on a FR4 substrate whose dielectric permittivity is 4.4. The substrate size measures an area of 46 mm X 28 mm, with 1.6 mm thickness. Also the design includes a microstrip feed and truncated ground. The antenna resonates well with a deep return loss of -38.9 dB in a broad bandwidth of 3.2 GHz (128 %) between 2 GHz and 5.2 GHz. The OMSFA produces enhanced gain of 9.8 dB at 2.5 GHz. The radiation is more focused due to the effect of metamaterial loading. The proposed antenna is recommended for wireless application in the lower region (S band) of the microwave spectrum.

In this work, a simple hydrothermal method was developed to synthesize CuO plates in centimeter scale for the first time. Plates of up to 20 μm thickness and several square millimeters in area have been prepared. The unusual size was obtained under ultrahigh-concentration NaOH and a planar chromium(III) oligomer, which served as a new kind of inorganic facet-directing agent. The obtained CuO plates were glossy black, free-standing, and crack-free. The chromium(III) oligomer offered ideal chemically active sites for adsorbing and confining Cu2+ ions. They could be adsorbed on the surface of Cu(OH)42- clusters via hydrogen-bonding interaction, which thus modified the growth orientation. The as-synthesized centimeter-scale CuO plates could possibly serve as substrates and electronic materials with potential applications.

Quality assurance of banknote printing plates is an important issue for the corporation which produces them. Every plate must be checked carefully and entirely before it's sent to the banknote printing factory. Previously the work is done by specific workers, usually with the help of powder and magnifiers, and often lasts for 3 to 4 hours for a 5*7 plate with the size of about 650*500 square millimeters. Now we have developed an automatic inspecting system to replace human work. The system mainly includes a stable platform, an electrical subsystem and an inspecting subsystem. A microscope held by the crossbeam can move around in the x-y-z space over the platform. A digital camera combined with the microscope captures gray digital images of the plate. The size of each digital image is 2672*4008, and each pixel corresponds to about 2.9*2.9 square microns area of the plate. The plate is inspected by each unit, and corresponding images are captured at the same relative position. Thousands of images are captured for one plate (for example, 4200 (120*5*7) for a 5*7 plate). The inspecting model images are generated from images of qualified plates, and then used to inspect indeterminate plates. The system costs about 64 minutes to inspect a plate, and identifies obvious defects.

This paper presents an active RF phase shifter with 10 bit control word targeted toward the upcoming 5G wireless systems. The circuit is designed and fabricated using 45 nm CMOS SOI technology. An IQ vector modulator (IQVM) topology is used which provides both amplitude and phase control. The design is programmable with exhaustive digital controls available for parameters like bias voltage, resonance frequency, and gain. The frequency of operation is tunable from 12.5 GHz to 15.7 GHz. The mean angular separation between phase points is 1.5 degree at optimum amplitude levels. The rms phase error over the operating band is as low as 0.8 degree. Active area occupied is 0.18 square millimeter. The total DC power consumed from 1 V supply is 75 mW.

PURPOSE To perform an age-stratified analysis of the effect of diabetes and pseudophakia on corneal endothelial cell density (ECD). METHODS This is a comparative analysis of donor characteristics from data supplied by the Lions Eye Institute for Transplant and Research on tissue harvested from July 1, 2007, through May 23, 2014. The mixed-effects model was used to compare age-adjusted mean corneal ECD between donors with and without diabetes. RESULTS A total of 20,026 nondiabetic donor eyes and 13,617 diabetic donor eyes were included in this study. ECD was 2604 cells per square millimeter in nondiabetic corneas and 2576 cells per square millimeter in diabetic corneas (P < 0.001). Among phakic patients, diabetic ECD was significantly less in the middle-age subgroups: -33 cells per square millimeter in the 21-to-40-year-old subgroup (P = 0.048) and -25 cells per square millimeter in the 41-to-60-year-old subgroup (P = 0.009). Among pseudophakic patients, diabetic ECD was significantly less only in the subgroup 61 years or older: -56 cells per square millimeter (P = 0.026). The magnitude of difference in ECD between phakic and pseudophakic donors was greater in patients with diabetes in the subgroup 61 years or older (P < 0.001). CONCLUSIONS Donor eyes with a history of diabetes had a slightly lower ECD (-29 cells/mm) than eyes without a history of diabetes. Although this statistical relationship is consistent with our pathophysiologic understanding of diabetes and the corneal endothelium, such a minor difference in ECD would be expected to have minimal clinical impact on overall corneal endothelial function.

BACKGROUND AND OBJECTIVE: Accurate quantification of retinal surface area from ultra-widefield (UWF) images is challenging due to warping produced when the retina is projected onto a two-dimensional plane for analysis. By accounting for this, the authors sought to precisely montage and accurately quantify retinal surface area in square millimeters. PATIENTS AND METHODS: Montages were created using Optos 200Tx (Optos, Dunfermline, U.K.) images taken at different gaze angles. A transformation projected the images to their correct location on a three-dimensional model. Area was quantified with spherical trigonometry. Warping, precision, and accuracy were assessed. RESULTS: Uncorrected, posterior pixels represented up to 79% greater surface area than peripheral pixels. Assessing precision, a standard region was quantified across 10 montages of the same eye (RSD: 0.7%; mean: 408.97 mm 2 ; range: 405.34–413.87 mm 2 ). Assessing accuracy, 50 patients’ disc areas were quantified (mean: 2.21 mm 2 ; SE: 0.06 mm 2 ), and the results fell within the normative range. CONCLUSION: By accounting for warping inherent in UWF images, precise montaging and accurate quantification of retinal surface area in square millimeters were achieved. [ Ophthalmic Surg Lasers Imaging Retina . 2014;45:312-317.]

PURPOSE We describe a technique of air-assisted anterior chamber intraocular lens (ACIOL) implantation. METHODS Lens aspiration and ACIOL implantation was performed in patients with progressive subluxation of lenses associated with systemic disorders. RESULTS Surgery was performed in nine eyes of six patients. No intraoperative adverse events were noted. There was air leak from the main port in three patients while inserting the intraocular lens; however the ACIOL was successfully implanted after re-injecting air from the side port. The mean best-corrected visual acuity improved from 0.67 to 0.25 log of minimal angle of resolution at 6-month follow-up. Mean intraocular pressure preoperatively was 14.54+1.38 mm Hg and 15.16+1.15 mm Hg at 6-month follow-up. Mean corneal endothelial count was 3,151+240.49 cells per square millimeter in the preoperative period and 2,947+194.9 cells per square millimeter at 6-month follow-up. CONCLUSIONS Air-assisted ACIOL implantation seems to be a safe and effective technique for implantation of ACIOL in cases with progressive lens subluxation.

PURPOSE To assess the corneal endothelium, particularly the polymegethism feature, using the Topcon SP-3000P specular microscope with newer center-dot software. METHODS Forty-eight healthy, normal weight, noncontact lens wearers of Asian ethnicity were assessed. Single endothelial images from each subject were processed with center-dot software, reevaluated after correction of obvious errors, and then by manual border marking and planimetry. Endothelial cell density based on average cell area and the coefficient of variation (COV) of cell area (polymegethism) were calculated. RESULTS Error sources are associated with erroneous location of cell borders (usually creating larger or smaller "cells") or failure to assign cell borders to a marked cell. On the initial application of the center-dot software, the endothelial cell density values ranged from 1822 to 3244 cells per square millimeter (mean, 2644 cells/mm); this range was reduced (eg, 1955-3054 cells/mm; mean 2690 cells/mm on editing or in manual planimetry). The COV values ranged from 17% to 39% (mean, 27.5% ± 5.5%), with one third of the endothelia yielding COV values of greater than or equal to 30%. On editing or in manual planimetry, the COV values were reduced to between 17% and 29% (mean, 24.5% ± 3.2%; P < 0.001). CONCLUSIONS In the use of a center-dot endothelial analysis program with cell border identification, it is likely that at least 1 set of editing steps is required to produce reasonable results.

Anatomical characteristics of White Jabon (Arthocephalus cadamba) and Red Jabon (Arthocephalus macrophyllus) were investigated by IAWA hardwood feature list. Both species were diffuse-porous, and radial multiple pore with 2~3 rows was mostly observed. Tangential diameter of vessel lumina was 100 to , and vessels per square millimeter were 5 to 20. White Jabon has more vessels than Red Jabon. The number of solitary pore per square millimeter in both species was similar, but more pore multiple was observed in White Jabon. Axial parenchyma diffuse was observed in both species, but axial parenchyma of White Jabon was hardly identified on the cross section. Rays were classified into "body ray cells procumbent with over 4 rows of upright/square marginal cells" type and partly "all ray cells upright and/or square" type on radial section. Ray width 1 to 3 cells and 1 to 2 cells observed in White Jabon and Red Jabon, respectively. Ray height of White Jabon was and Red Jabon . Fiber length was the range of 900 to in both species, and it showed a tendency to increase from pith to bark. Consequently, it is considered that pore multiple, ray width and axial parenchyma are to be suggested the keys for identification of both species.

This paper presents the design of a novel single square millimeter three-axial accelerometer for head injury detection of racing car drivers. The main requirements of this application are miniaturization and medium/high-G measurement range. We propose a new miniature accelerometer to be incorporated into an earpiece. Nanowires as nanoscale piezoresistive devices have been chosen as sensing element, due to their high sensitivity and miniaturization achievable. By exploiting the electromechanical features of nanowires as nanoscale piezoresistors, the nominal sensor sensitivity is overall boosted by more than 30 times. This approach allows significant higher accuracy and resolution with smaller sensing element in comparison with conventional devices without the need of signal amplification. This achievement opens up new developments in the area of implanted devices where the high-level of miniaturization and sensitivity is essential.

The number of neurons under a square millimeter of cortical surface has been reported to be the same across five cortical areas and five species [Rockel et al. (1980) Brain 103(2):221–244] despite differences in cortical thickness between the areas. Although the accuracy of this result has been the subject of sharp debate since its publication approximately 30 y ago, the experiments of Rockel et al. have never been directly replicated with modern stereological methods. We have replicated these experiments and confirm the accuracy of the original report. In addition, we have observed that the number of glial cells under a square millimeter of cortical surface depends on cortical thickness, but not on cortical area or species.

Objectives The purpose of this study was to assess the effects of acute joint effusion on balance in patients with knee osteoarthritis. Design Forty-four female subjects with painful knee osteoarthritis participated in this single-blind, randomized, controlled clinical trial. All subjects were randomly assigned to either the injection or the control group. A volume of 20 ml of normal saline was injected into the knee joint cavity of the test subjects, who performed static and dynamic balance tests twice before and after joint infusion. The subjects in the control group performed the same tests without joint infusion. The outcome variables for static measurement were the mean speeds (millimeter per second) of the movement of the center of pressure in the mediolateral and anteroposterior directions and the mean velocity moment (square millimeter per second) with both eyes opened and eyes closed conditions. For dynamic measurement, time (second) and distance (millimeter) of the center of pressure were used. Results Significant interaction of the balance-test variables (mean speeds, velocity moment, time, and distance) between the groups and time (P > 0.05) was not found. There were no significant differences between the groups in any of the balance-test variables (P > 0.05). Conclusions This study showed that acute joint effusion has no effect on static or dynamic postural sway in patients with knee osteoarthritis.

A micro surface tension pump is a new type of low-cost, built-in, all-glass, microfluidic pump on a glass microchip fabricated by one-step glass etching. However, geometric minimization and optimization for practical use are challenging. Here, we report a one-square-millimeter, built-in, all-glass pump controlled by two-way digital gas pressure. The pump consists simply of two joint chambers and a piston between two gas control channels. It does not require pre-perfusion for initialization, and can immediately begin to run when a liquid enters its inlet channel. It is also more reliable than conventional micro pumps for practical use due to its ability to restart after the formation of a blocking bubble, which can serve as a valuable troubleshooting procedure. Its volumetric pump output was 0.5⁻0.7 nL·s-1 under a pump head pressure of 300 Pa.

PURPOSE: To investigate the repeatability of the semiautomatic assessment of corneal endothelial cells and its association with the measurement area in the Topcon SP-2000P microscope and IMAGEnet system. METHODS: Specular microscopic images of 86 healthy subjects were captured and analyzed using the Topcon SP-2000P microscope and IMAGEnet system. The same images were analyzed twice, on separate days, by the same examiner using the built-in measurement tool of the IMAGEnet system. The measurement areas were defined with a frame mounted on a computer screen. Four different-sized measurement areas were chosen for the semiautomatic measurements: box A (5.4 × 13.9 cm(2)), box B (4 × 10 cm(2)), box C (4 × 7 cm(2)), and box D (2 × 5 cm(2)). Average cell size (ACS), endothelial cell density (ECD), coefficient of variance, and hexagonality were measured. Repeatability was assessed based on the limit of agreement (LOA). RESULTS: The means of ACS, ECD, and hexagonality were not statistically different across 4 measurement areas (analysis of variance, P > 0.05). The mean differences (bias) were modest for ACS (range, -1.9∼3.9 μm(2)), ECD (range, -27.2∼14.6 cells per square millimeter), coefficient of variance (range, -0.14∼1.00), and hexagonality (range, -1.3%∼6.8%). Limits of agreement (mean difference ± 1.96× SD) were greater in the measurements with smaller areas: limit of agreement values for ECD were 14.6 ± 99.6, -3.8 ± 101.1, -27.2 ± 179, and -15.8 ± 488 cells per square millimeter for boxes A, B, C, and D, respectively. Similar trends were found in the repeatability of ACS and hexagonality. CONCLUSIONS: Repeatability is improved when larger measurement areas are chosen.

PURPOSE To assess the impact of using different sampling areas (fields of view) on the reliability of goblet cell density (GCD) estimates from conjunctival impression cytology (CIC) specimens from healthy individuals. METHODS The CIC specimens were collected from the exposed nasal bulbar conjunctiva of 5 adult subjects (average age, 23 years) onto Biopore (Millicell) membranes and stained with Giemsa. A region from each of the specimens that contained abundant goblet cells was examined by light microscopy using a ×40 magnification objective lens, ×20 and ×10 lenses, the images were enlarged, and the goblet cells were marked and counted. The GCD values per square millimeter were calculated and then the impact of counting between 10 to many and 10 to few goblet cells assessed. RESULTS The mean GCD estimates at ×400 magnification, ×200, and ×100 were 950 ± 226, 620 ± 154 and 471 ± 158 cells per square millimeter, respectively; these values were statistically different (P

The cleanness of 30Cr2Ni4MoV steel was researched by chemical analysis, SEM and electrolytic experiment. The results show that the large-sized inclusions in the casting is the direct reason for the product to scrap. It found that there is a increase trend of large-sized inclusions and oxygen content from VD to pouring process with a cleanness detection of smelting process. It have achieved a good effect by adopting some measures to improve steel cleanliness which includes controlling the carbon content of EAF tapping reasonablly, low melting point controlling of inclusions, extending soft blow time and optimizing the flow field of tundish. The quantity of inclusions has reduced from 38.8 per square millimeter to 16.0 per square millimeter. The oxygen content has reduced from 58 × 10-6 to 32 × 10-6, and the nitrogen contents has reduced from 85 × 10-6 to 70 × 10-6 after process improvment.

Laser triangulation was used to measure the topography of vitrified CBN wheels and optimum sampling interval was obtained by comparing measuring results with different sampling intervals. Four evaluation indexes including the mean protrusion height of abrasive grains Hm, the standard deviation of grain protrusion height Hv, the standard deviation of the distance between two adjacent grains Dv and the number of micro cutting edges per square millimeter Nm were put forward to assess wheel topography and grinding performance. These indexes were verified to be effective by comparing 3D topography of newly manufactured wheel and dressed wheel.

With the aim of establishing exposure levels for hospital personnel preparing and administering cytostatic drugs (CDs), here, we present an innovative screening method based on the use of the desorption electrospray ionization (DESI) interface coupled with a hybrid quadrupole linear ion trap mass spectrometer. A rapid, simple, and sensitive procedure was developed for the simultaneous surface monitoring of cyclophosphamide, dacarbazine, methotrexate, vincristine, gemcitabine, and cytarabine. Since analytes were in the solid state, a novel approach based on the use of passive samplers was combined with the direct analysis of wipes. A PTFE-printed glass slide was used as a passive sampler, while hydrophobic centers of Swiffer® cloths were judged extremely efficient as wipe samplers. After the sampling period, the CD collectors were directly processed with the DESI-MS system without any further treatment. MS/MS confirmatory analysis was conducted using selected reaction monitoring in the positive ion mode and detection limits were evaluated. Values were at the picograms per square millimeter levels on the passive collector and at the picograms per square centimeter levels for the wipe ones. Direct determination on solid-state samples combined with mass spectrometry selectivity provided a powerful tool so far unapplied to occupational hygiene.

PURPOSE To assess the keratocyte density (KD) in the cornea of patients with keratoconus not using contact lenses. METHOD In this pilot study, the eyes (n = 68) of 35 patients with the diagnosis of keratoconus, who did not use contact lenses and the eyes(n = 70) of 35 healthy controls were prospectively examined using the Heidelberg Retinal Tomography Rostock cornea module (HRT3/RCM). The cases with keratoconus and controls were compared with regard to KD in the anteroposterior stromal layers. RESULTS Of the cases with keratoconus, 15 (42.9%) were men and 20 (57.1%) were women. The mean age was 21.1 ± 11.1 (range =14-41) years. Of the controls, 26 (73.9%) were men and 9 (26.1%)were women. The mean age was 23.9 ± 12.9 (range = 14-35) years.Of the 68 eyes with keratoconus, 22 (28.2%) had mild keratoconus, 23 (35.9%) had moderate keratoconus, and 23 (35.9%) had severe keratoconus. The mean anterior stromal KD was 651.4 ± 89 cells per square millimeter in cases with keratoconus and 879.4 ± 75 cells per square millimeter in controls (P < 0.05). The mean anterior stromal KD decreased by 25.9% in corneas with keratoconus. The mean posterior stromal KD was found to be 363.6 ± 74 cells per square millimeter in cases with keratoconus and 469.7 ± 56 cells per square millimeter in controls (P< 0.01). The mean posterior stromal KD decreased by 22.6% in corneas with keratoconus. The anterior stromal KD was higher than the posterior stromal KD (P < 0.001). No significant relationships were found between the stromal KD data and central corneal thickness or steepest keratometric. CONCLUSIONS The KD in the anterior and posterior corneal stroma was decreased in patients with keratoconus, but without the use of contact lens, compared with healthy controls. This density difference was independent from the central corneal thickness and the stage of keratoconus.

Objectives: Dendritic cells (DCs) are key instigators of rejection after transplantation. Their distribution has not been systematically characterized in all locations of the larynx and its surrounding tissues. Methods: Rat larynges were stained with monoclonal antibodies identifying DCs. These cells were then enumerated by a new combination of techniques including immunofluorescence, confocal microscopy, and imaging software. Results: The vast majority of DCs were located in the epithelium and subepithelium of the airway; the mean DC density ranged from 9 cells per square millimeter (0.2% of cells) to 645 cells per square millimeter (10.3% of cells). Their density in the epithelium was 3 to 11 times higher than that in the subepithelium. Non-airway sites (thyroid, parathyroid, muscle, fat) had mean DC densities varying from 3 cells per square millimeter (0.2%) to 57 cells per square millimeter (0.8%). No DCs were detected in cartilage. Conclusions: Dendritic cells are concentrated in the laryngotracheal epithelium and subepithelium and represent a much smaller proportion in the other sites studied. A baseline for laryngeal DC population studies has been established, and a computerized model for consistent quantitation using confocal microscopy has been developed. This unique method will serve as a foundation for investigating DC trafficking after rat laryngeal transplantation.

OBJECTIVES The aims of the study were to use cone beam computed tomography (CBCT) images of nasopalatine duct cysts (NPDC) and to calculate the diameter, surface area, and 3D-volume using a custom-made software program. Furthermore, any associations of dimensions of NPDC with age, gender, presence/absence of maxillary incisors/canines (MI/MC), endodontic treatment of MI/MC, presenting symptoms, and postoperative complications were evaluated. MATERIAL AND METHODS The study comprised 40 patients with a histopathologically confirmed NPDC. On preoperative CBCT scans, curves delineating the cystic borders were drawn in all planes and the widest diameter (in millimeter), surface area (in square millimeter), and volume (in cubic millimeter) were calculated. RESULTS The overall mean cyst diameter was 15 mm (range 7-47 mm), the mean cyst surface area 566 mm(2) (84-4,516 mm(2)), and the mean cyst volume 1,735 mm(3) (65-25,350 mm(3)). For 22 randomly allocated cases, a second measurement resulted in a mean absolute aberration of ±4.2 % for the volume, ±2.8 % for the surface, and ±4.9 % for the diameter. A statistically significant association was found for the CBCT determined cyst measurements and the need for preoperative endodontic treatment to MI/MC and for postoperative complications. CONCLUSION In the hands of a single experienced operator, the novel software exhibited high repeatability for measurements of cyst dimensions. Further studies are needed to assess the application of this tool for dimensional analysis of different jaw cysts and lesions including treatment planning. CLINICAL RELEVANCE Accurate radiographic information of the bone volume lost (osteolysis) due to expansion of a cystic lesion in three dimensions could help in personalized treatment planning.

A switch-decoded based current-steering architecture is proposed for calibration DAC of ADCs. The circuit and working principle of the proposed switch-decoded current-steering DAC is introduced. A 14-bit DAC is realized in 0.18um CMOS process by combining an 8-bit switch-decoded current-steering DAC with a 6-bit binary-weight DAC. The chip area taken by the 14-bit DAC is only 0.1 square millimeters. The simulation shows that the DNL is +0.18/−0.52LSB and the INL is +1.5/−2.3LSB.

Three decades ago, Rockel et al. proposed that neuronal surface densities (number of neurons under a square millimeter of surface) of primary visual cortices (V1s) in primates is 2.5 times higher than the neuronal density of V1s in nonprimates or many other cortical regions in primates and nonprimates. This claim has remained controversial and much debated. We replicated the study of Rockel et al. with attention to modern stereological precepts and show that indeed primate V1 is 2.5 times denser (number of neurons per square millimeter) than many other cortical regions and nonprimate V1s; we also show that V2 is 1.7 times as dense. As primate V1s are denser, they have more neurons and thus more pinwheels than similar-sized nonprimate V1s, which explains why primates have better visual acuity.

Sensitive, real-time detection of biomarkers is of critical importance for rapid and accurate diagnosis of disease for point of care (POC) technologies. Current methods do not allow for POC applications due to several limitations, including sophisticated instrumentation, high reagent consumption, limited multiplexing capability, and cost. Here, we report a nanocoaxial-based electrochemical sensor for the detection of bacterial toxins using an electrochemical enzyme-linked immunosorbent assay (ELISA) and differential pulse voltammetry (DPV) or square wave voltammetry (SQV). The device architecture is composed of vertically-oriented, nanoscale coaxial electrodes in array format (~106 coaxes per square millimeter). The coax cores and outer shields serve as integrated working and counter electrodes, respectively, exhibiting a nanoscale separation gap corresponding to ~100 nm. Proof-of-concept was demonstrated for the detection of cholera toxin (CT). The linear dynamic range of detection was 10 ng/ml – 1 μg/ml, and the limit of detection (LOD) was found to be 2 ng/ml. This level of sensitivity is comparable to the standard optical ELISA used widely in clinical applications, which exhibited a linear dynamic range of 10 ng/ml – 1 μg/ml and a LOD of 1 ng/ml. In addition to matching the detection profile of the standard ELISA, the nanocoaxial array provides a simple electrochemical readout and a miniaturized platform with multiplexing capabilities for the simultaneous detection of multiple biomarkers, giving the nanocoax a desirable advantage over the standard method towards POC applications.

The use of bottom-up approaches to construct patterned surfaces for technological applications is appealing, but to date is applicable to only relatively small areas (∼10 square micrometers). We constructed highly periodic patterns at macroscopic length scales, in the range of square millimeters, by combining self-assembly of disk-like porphyrin dyes with physical dewetting phenomena. The patterns consisted of equidistant 5-nanometer-wide lines spaced 0.5 to 1 micrometers apart, forming single porphyrin stacks containing millions of molecules, and were formed spontaneously upon drop-casting a solution of the molecules onto a mica surface. On glass, thicker lines are formed, which can be used to align liquid crystals in large domains of square millimeter size.

A new implementation of a SNOM is described, aiming at the topographical study of large areas and exploiting the advantages of the shear-force detection system. This technique finds very interesting application in the study of archeological or artistic samples, where it often occurs that an area to be examined at high resolution (optically, topographically or chemically) is enclosed in a wider one. The implemented system allows to obtain scans of wide areas by using dc-motors to move the sample under the probe tip, and thus it can face rough samples with height differences of several tens of micrometers. It allows the user to choose whether to use the SNOM to study the optical and topographical properties of a small part of the sample (up to tens of square micrometers), or to use the motor-driven scan technique, to study the topographical characteristic of a large area of the sample (up to some square millimeters) and even over rough surfaces. We show results detecting worn relieves over a coin. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Background: The evaluation of the endothelial cells is the most important criterion for assessing human donor corneas. The number, morphology and the vitality of the endothelial cells are decisive for the transparency of a cornea. The study has the following aim: to verify whether there is any difference between the manual and the automatic count of the cells by means of the NAVIS® system. Material and Methods: Both methods were performed on 57 corneas of 35 patients. A photo was taken for the manual count by a microscope at 40-fold enlargement and was printed for further analysis. A grid was applied to this photo and the number of the endothelial cells was projected by a multiplicator to one square millimeter. For the automatic evaluation a picture was made with 20-fold microscopic enlargement; the examiner chose an area to be analysed. There the count of the cells was controlled by software and directly projected to one square millimetre. This was followed by a manual correction. The measurement data were statistically evaluated. Results: No statistically significant difference was found between the manual and automatic counts. Conclusion: The manual count of the endothelial cells can be replaced by software-controlled automatic analysis and count.

The influence of repeated freeze–thawing on pore structural characteristics and physical properties of porous silk fibroin materials prepared by freeze drying were studied. It showed that when quick-frozen silk fibroin solution was repeatedly thawed and frozen before being vacuum dried, thus pore size of prepared porous silk fibroin materials increased from 67 µm to about 120 µm, and pore density decreased from 80 per square millimeter to about 28 per square millimeter; at the same time compression ratio and moisture permeability increased from 22.7% and 230 g/m2 hr to about 33.7% and 308 g/m2 hr, respectively, tensile strength and dissolvability in hot water decreased from 20.2 N/cm2 and 42.7% to about 12.5 N/cm2 and 26.1%, respectively. Both the times of repeated thawing and the thawing temperature had a certain influence on the above-mentioned pore characteristic parameters and physical properties. Copyright © 2001 John Wiley & Sons, Ltd.

The distribution of the pore sizes was measured for more than hundred specimens with an total area of 16000 square millimeters of recrystallized siliconcarbide specimens, from which the bending strength values were known. The parameters of the Weibull distribution of the strength were predicted from the distribution of the pore sizes. The reliability of the prediction was calculated by taking out arbitrary subsets of these specimens, corresponding to sub-areas of the total area, and investigating the statistical distribution in dependence on the size of the pores in these subsets. The so obtained mean and the variation coefficient were compared to the results from the mechanical bending tests.

PURPOSE: To determine if the timing of mitomycin C (MMC) application during pterygium surgery affects endothelial cell loss. METHODS: A retrospective, nonrandomized, case-series design was used. The study group included 40 patients who underwent pterygium surgery with the bare sclera technique. MMC 0.02% was applied intraoperatively for 5 minutes, either before (16 patients) or after (24 patients) excision of the head of the pterygium. Endothelial images were acquired at the center of the cornea with a specular microscope before surgery and at 3 intervals during follow-up (average of 3 measurements each). Differences in cell loss from baseline were analyzed by paired t test. RESULTS: In the group in which MMC was applied post excision, mean preoperative endothelial cell count was 2254 +/- 128 cells per square millimeter. Mean postoperative values were 1775 +/- 63 cells per square millimeter at 1 week (percentage cell loss, 21.25% +/- 2.8%), 1707 +/- 41 cells per square millimeter at 1 month (24.26% +/- 1.8%), and 1780 +/- 72 cells per square millimeter at 3 months (21.05% +/- 3.2%). The difference in cell count from the preoperative value was significant at all time points (P < 0.02). In the group in which MMC was applied before excision, mean preoperative endothelial cell count was 2352 +/- 118 cells per square millimeter, and mean postoperative values were 2345 +/- 120 cell per square millimeter at 1 week, 2260 +/- 162 cells per square millimeter at 1 month, and 2230 +/- 144 cells per square millimeter at 3 months. No endothelial cell loss was documented in this group. CONCLUSION: The endothelial cell loss associated with the use of MMC during pterygium surgery might be avoided by applying MMC before excision of the pterygium head, so that it does not come into contact with the corneal surface.

Transportation, metering, and mixing of picoliter-sized liquid samples were realized in a microfluidic device with a main working area of one square millimeter. The device was constructed by sealin...

We have used a facile polymer imprint process to fabricate a three-dimensional electrochemical nanosensor, the sensitivity of which is two decades higher than that of planar controls. The device is composed of an array of vertically oriented nanoscale coaxial electrodes, with the coax cores and shields serving as integrated working and counter electrodes, respectively, each with a nanoscale separation gap (coax annulus width). Arrays of ~10(6) devices per square millimeter were prepared with different gaps, with smaller gaps yielding higher sensitivity. A coax-based sensor with a 100 nm gap was found to have sensitivity 90 times greater than that of a planar sensor control, which had conventional millimeter-scale electrode gap spacing. We suggest that this enhancement is due to the combination of rapid diffusion of molecules between the closely spaced electrodes and the large number of nanoscale electrochemical cells operating in parallel, both of which enhance current per unit surface area compared to planar or other nanostructured devices.

Purpose: To establish intraobserver and interobserver repeatability, agreement, and symmetry of corneal nerve fiber (NF) morphology in healthy subjects using in vivo corneal confocal microscopy. Methods: Nineteen subjects underwent in vivo corneal confocal microscopy (Heidelberg Retinal Tomograph III Rostock Cornea Module) at baseline and 7 days apart. Bland-Altman plots were generated to assess agreement, and the intraclass correlation coefficient and coefficient of repeatability were calculated to estimate intraobserver and interobserver repeatability for corneal NF density (numbers per square millimeter), nerve branch density (NBD; numbers per square millimeter), NF length (millimeters per square millimeter), and NF tortuosity coefficient. Symmetry between the right and left eyes was also assessed. Results: Intraclass correlation coefficient and coefficient of repeatability for intraobserver repeatability were 0.66 to 0.74 and 0.17 to 0.64, for interobserver repeatability 0.54 to 0.93 and 0.15 to 0.85, and for symmetry 0.34 to 0.77 and 0.17 to 0.63, respectively. NBD demonstrated low repeatability. Conclusions: This study demonstrates good repeatability for the manual assessment of all major corneal NF parameters with the exception of NBD, which highlights the difficulty in defining nerve branches and suggests the need for experienced observers or automated image analysis to ensure optimal repeatability. © 2013 Lippincott Williams & Wilkins.