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Infertility is a growing global health issue with far-reaching socioeconomic implications. A downward trend in male fertility highlights the acute need for affordable and accessible diagnosis and treatment. Assisted reproductive technologies are effective in treating male infertility, but their success rate has plateaued at ∼33% per cycle. Many emerging opportunities exist for microfluidics — a mature technology in other biomedical areas — in male infertility diagnosis and treatment, and promising microfluidic approaches are under investigation for addressing male infertility. Microfluidic approaches can improve our fundamental understanding of sperm motion, and developments in microfluidic devices that use microfabrication and sperm behaviour can aid semen analysis and sperm selection. Many burgeoning possibilities exist for engineers, biologists, and clinicians to improve current practices for infertility diagnosis and treatment. The most promising avenues have the potential to improve medical practice, moving innovations from research laboratories to clinics and patients in the near future.

Exploratory spatial data analysis (ESDA) plays a key role in research that includes geographic data. In ESDA, analysts typically need to visualize observations and local relationships on a map. However, software dedicated to visualizing local degrees of association between multiple variables in high-dimensional geospatial datasets remains undeveloped. This paper introduces gwpcorMapper, a newly developed software application for mapping geographically weighted (GW) correlation and partial correlation statistics in high-dimensional datasets. gwpcorMapperfacilitates ESDA by giving researchers the ability to interact with map components that describe local correlative relationships. gwpcorMapperis an open source and is built using the R Shiny framework. The software inherits its algorithm logic from GWpcor, an R library for calculating the geographically weighted correlation and partial correlation statistics. We demonstrate the application of gwpcorMapperby using it to investigate census data to find meaningful relationships that describe the work-life environment in the 23 special wards of Tokyo, Japan. gwpcorMapperis useful in both variable selection and parameter tuning for GW statistics.

The following study investigates splashing of impinging water droplets on superhydrophobic surfaces with and without the presence of a stagnation flow. Droplets were accelerated by either gravity or gravity and co-flow. By changing the height and the air flow velocity different combinations of stagnation flow and droplet velocity were created. The spreading diameter, spreading velocity and contact time were studied for different air and droplet speeds. It was clearly observed that for a fixed impact velocity (i.e. constant Weber number), the presence of the stagnation flow promotes splashing and formation of satellite droplets. Consequently, for the co-flow droplet impact experiments, the mass of the recoiled droplet is significantly smaller than that of the impinging droplet in still air.

We present an overview of the performance of the High Speed Photometer (HSP), one of the five original instruments on the Hubble Space Telescope(HST). As its name implies, the HSP was designed for precise high time resolution photometry from visual to ultraviolet wavelengths; sample times as short as 10.7 ?s were possible. Three image dissectors along with 23 different broad- and narrowband filters spanning the spectral range from 1200 to 7500 Å were used for photometry of stars and galaxies. A fourth image dissector with associated polarization analyzers allowed the measurement of broadband linear polarization at near-ultraviolet wavelengths. Simultaneous observations in the blue and red could be made using one of the dissectors and a photomultiplier. Except for an instability in the sensitivity of one of the image dissectors and a reduced throughput in a specialized observational mode, the instrument met or exceeded operational specifications until it was removed from HSTin 1993 December. The ability of HSP to carry out its primary program, however, was nearly totally compromised by the poor performance of the telescope, i.e., the spherical aberration of the primary mirror that greatly amplified the effects of large spacecraft pointing jitter and telescope "breathing." As a consequence, the real possibility of HST/HSP opening a new era of astronomical photometry was lost. HSP data affected by various telescope problems, as well as data in which these complications were relatively small, are shown. The excellent condition of the HSP after its return to Earth is described briefly.

Golgi membranes and Golgi-derived vesicles are associated with multiple cytoskeletal proteins and motors, the diversity and distribution of which have not yet been defined. Carrier vesicles were separated from Golgi membranes, using an in vitro budding assay, and different populations of vesicles were separated using sucrose density gradients. Three main populations of vesicles labeled with beta-COP, gamma-adaptin, or p200/myosin II were separated and analyzed for the presence of actin/actin-binding proteins. beta-Actin was bound to Golgi cisternae and to all populations of newly budded vesicles. Centractin was selectively associated with vesicles co-distributing with beta-COP-vesicles, while p200/myosin II (non-muscle myosin IIA) and non-muscle myosin IIB were found on different vesicle populations. Isoforms of the Tm5 tropomyosins were found on selected Golgi-derived vesicles, while other Tm isoforms did not colocalize with Tm5 indicating the association of specialized actin filaments with Golgi-derived vesicles. Golgi-derived vesicles were shown to bind to F-actin polymerized from cytosol with Jasplakinolide. Thus, newly budded, coated vesicles derived from Golgi membranes can bind to actin and are customized for differential interactions with microfilaments by the presence of selective arrays of actin-binding proteins.

Abstract:: Osteoporosis is a major public health problem characterized by low bone mineral density (BMD) that presently has no biochemical test useful for its diagnosis. The cytokine TGF-β has been postulated to play a role in controlling bone density by regulating the fine balance between bone matrix deposition by osteoblasts and its resorption by osteoclasts. We explored whether measurement of serum levels of different TGF-β isoforms could be useful as a clinical tool in osteoporosis. We measured the concentration of TGF-β1 antigen using the BDA19 capture sandwich enzyme-linked immunosorbent assay (ELISA), TGF-β2 antigen concentration using a Quantikine sandwich ELISA kit and TGF-β3 antigen concentration using a modified version of the TGF-β1 Quantikine sandwich ELISA kit. Subjects were 41 women with osteoporosis (with nontraumatic vertebral fracture or lumbar spine BMD Z-score <−1.5 SD) and a total of 199 control women from different sources. Serum concentrations of TGF-β1 and TGF-β2 were similar in all groups. However, detectable levels of TGF-β3 (>0.2 ng/ml) were found in 35 of 41 patients with osteoporosis (median 7.2 (5.2–8.9) ng/ml) compared with 11 of 36 controls or 24 of 89 healthy women of unknown bone density. Differences among the groups could not be accounted for by age, weight, medications, use of hormone replacement therapy or the presence of osteoarthritis. Using the optimal cut-off of ≥2 ng/ml, the test was able to detect an individual with low spine BMD (Z-score <−1.5) with a sensitivity of 84% and a specificity of 53%, with similar results for the femoral neck. The odds ratio for osteoporosis associated with a positive test at this level was 5.93 (95% CI 2.41–11.59), and 4.1 (95% CI 1.66–10.11) using the WHO cut-off of T-score <−2.5. Serum TGF-β3 concentration is raised in osteoporotic women and the test appears to have potential as a marker for osteoporosis. The underlying mechanisms and the relationships between TGF-β3 and bone turnover and fractures remain to be explored.

We report the first polarimetric observations in the ultraviolet of two AGN's, the blazar BL Lac and the gravitational lens candidate Q2345+007. We find strong (p>3%) and variable UV polarization in BL Lac, two of the characteristics exhibited by blazars in the visible. The polarization of BL Lac in the UV decreased significantly (from 18% to <5%) over a timescale of days. The flux density in the polarimetric bandpass showed changes which were not correlated with the polarimetric changes. The behavior of BL Lac in the UV is consistent with the two-component model of its polarized flux proposed by Brindleet al. (1985). The UV properties of the images in the Q2345+007 system are consistent with a gravitational lens interpretation. The QSO imaged in Q2345+007A is an excellent candidate to monitor for variable polarization on a timescale of weeks. Detecting the same polarimetric variation in each image of a gravitational lens may be the most effective method of determining the time-of-flight difference between the two image paths.

In an attempt to better understand the origin of deep crustal reflections LITHOPROBE has sponsored or co-sponsored Seismic reflection surveys across tracts of high-grade metamorphic rock in the Archean Superior craton, the Proterozoic Grenville orogen and the Phanerozoic Cordilleran orogen. Common to these three diverse terranes are near-surface zones of prominent Seismic reflectivity that are typically associated with velocity discontinuities at highly strained contacts between gneissic rocks of varying lithology. At some locations the reflective layering resulted from transposition and rearrangement of previously layered rocks (stratified assemblages, sills, etc.), whereas in other regions it was generated by extreme attenuation, stretching and ductile flow of weakly layered or irregularly organized rocks. It seems likely that compositionally layered gneissic rock is a common source of reflections in the deep crust, with reflections originating at lithological boundaries and zones of mylonite.

Abstract. The Wisconsin HaMapper (WHAM) is a recently completed facility for the detection and study of faint optical emission lines from diffuse ionised gas in the disk and halo of the Galaxy. WHAM consists of a 15 cm diameter Fabry–Perot spectrometer coupled to a 0·6 m ‘telescope’, which provide a 1° diameter beam on the sky and produce a 12 km s-1resolution spectrum within a 200 km s-1spectral window. This facility is now located at Kitt Peak in Arizona and operated remotely from Madison, Wisconsin, 2400 km distant. Early results include a velocity-resolved Hamap of a 70° × 100° region of the sky near the Galactic anticentre, the first detections of Haemission from the M I and A high velocity clouds, and the first detections of [O I] ?6300 and other faint ‘diagnostic’ lines from the warm ionised medium. Through the summer of 1998, WHAM will be devoted almost exclusively to a survey of the northern sky, which will provide maps of the distribution and kinematics of the diffuse HII through the optical Haline in a manner that is analogous to earlier sky surveys of the HI made through the 21 cm line.

Far-ultraviolet spectra of the gravitational lens components Q0957+561A and B were obtained with the HubbleSpaceTelescopeFaint Object Spectrograph (HSTFOS). Two previously known absorption-line systems were detected at redshifts zdamped= 1.3911 and zLy?= 1.1249. Their prominent absorption features are superposed on intense QSO continuum emission between ??900-1400 in the quasar rest frame. Strong O VI?1033, Ly? ?1216, and N V?1240 line emission found at the QSO redshift (zQSO= 1.41) accompany the absorption-line systems. Ly? through Lyassociated with the damped absorption system were found in both lensed components, together with other ionic species of N I, N III, C II, C III, Si II, Si III, and O I. We tentatively identify O VI??1033, 1037 absorption at the damped Ly? redshift, which, if confirmed, would be the highest ionization species yet detected in such systems. The equivalent widths of the Lyman series in Q0957+561A are measurably greater compared with absorption in 0957+561B, consistent with the narrower and shallower depth of the Lyman series line profiles in image B. The differences of the damped Lyman series absorption in the lensed components are the only significant spectral characteristic that distinguishes the far-ultraviolet spectra of 0957+561A and B. These results indicate that the damped Ly? absorber is inhomogeneous over scale lengths of ~200 pc, which corresponds to the beam separation at the damped Ly? redshift. However, the equivalent widths of neutral and ionized metals in lens components A and B are correlated, which suggests these spectral features arise in an extended region. The metal line-absorption strength is consistent with lower column densities compared with the hydrogen line-forming region. Thus, the small coherence length scale indicated by the difference in hydrogen line absorption between the lensed components suggests the geometric ray paths intercept different regions of a galactic disk that is viewed pole-on, while the metal absorption occurs in the halo.

An investigation of the nature of the thermal diode background in integrating photodiode detectors is presented. The Weckler's (1967) nonlinear model was extended to the general situation of comparable dark and photocurrents, and the model with a self-scanned diode array detector was verified. It was found that a naive linear subtraction of a scan of background from a scan of signal plus background introduces a small multiplicative error in the apparent gain of the detector; the fractional gain error is approximately equal to the fraction of diode saturation due to integrated dark current and does not depend on the amount of illumination. A simple linear correction algorithm is described which allows the use of integration times for which diode background becomes a large fraction of diode saturation allowing detection of lower light levels. A sample application of the correction formula allows operation at a convenient dry-ice pumped-alcohol temperature for exposure times of up to 200 s.

FOLLOWING warm autumn rains after summers of above-average temperatures, rapidly growing pastures in some districts of New Zealand are capable of producing an hepatotoxin causing serious losses in sheep and cattle. A minority of the affected animals exhibit the clinical symptoms described as ‘facial eczema’1.

A PREVIOUS communication1reported that spores of a fungus identified as Sporidesmium bakeri Syd. contained the ‘beaker test’ substance found to be associated with toxicity of pasture samples on which the disease known as facial eczema had occurred.