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Cellular senescence has proved to be a strong contributor to ageing and age-related diseases, such as cancer and atherosclerosis. Therefore, the protein content of senescent cells is highly relevant to drug discovery, diagnostics and therapeutic applications. However, current technologies for the analysis of proteins are based on a combination of separation techniques and mass spectrometry, which require handling large sample sizes and a large volume of data and are time-consuming. This limits their application in personalised medicine. An easy, quick and inexpensive procedure is needed for qualitative and quantitative analysis of proteins expressed by a cell or tissue. Here, we describe the use of the "snapshot imprinting" approach for the identification of proteins differentially expressed by senescent cells. Molecularly imprinted polymer nanoparticles (MIPs) were formed in the presence of whole cells. Following trypsinolysis, protein epitopes protected by complex with MIPs were eluted from the nanoparticles and analysed by LC-MS/MS. In this work, "snapshot imprinting" was performed parallel to a standard proteomic "shaving approach", showing similar results. The analysis by "snapshot imprinting" identified three senescent-specific proteins: cell division cycle 7-related protein kinase, partitioning defective three homolog B and putative ATP-dependent RNA helicase DHX57, the abundance of which could potentially make them specific markers of senescence. Identifying biomarkers for the future elimination of senescent cells grants the potential for developing therapeutics for age-related diseases.

Objective To provide guidance for the comprehensive management of children referred for anterior drooling. The mission of the International Pediatric Otolaryngology Group (IPOG) is to develop expertise-based recommendations for the management of pediatric otolaryngologic disorders with the goal of improving patient care. Methods Survey of expert opinion by the members of the International Pediatric Otolaryngology Group (IPOG). The recommendations are derived from current expert consensus and critical review of the literature. Results Consensus recommendations include initial care and approach recommendations for health care providers who commonly evaluate children with drooling. This includes evaluation and treatment considerations for commonly debated issues in drooling management, initial work-up of children referred for anterior drooling, treatment recommendations, indications and contra-indications for rehabilitation, medical, and surgical management, as well as pros and cons of different surgical procedures in the hands of drooling management experts. Conclusion Anterior drooling consensus recommendations are aimed at improving patient-centered care in children referred for sialorrhea.

The Michigan Business & Entrepreneurial Law Review (MBELR) has always strived to provide a platform for legal scholars, professionals, and students to publish business-related legal scholarship. Yet, little legal business scholarship focusing on the Black business community exists, despite the extraordinary impact that Black communities have in the U.S. business landscape. In a year of revolutionary social change, we are excited to feature in this special issue the work of Professor Dana Thompson, a Michigan Law alumna, in an effort to remedy this gap. Professor Thompson’s career, professional values, and day-to-day work demonstrate genuine, commanding, and inspiring commitment to social justice and community-based organizations.

Spermatozoa normally encounter the egg at the fertilization site (in the Fallopian tube) within 24 hr after ovulation. A considerable fraction of the spermatozoa ejaculated into the female reproductive tract of mammals remains motionless in storage sites until ovulation, when the spermatozoa resume maximal motility and reach the fertilization site within minutes. The nature of the signal for sperm movement is not known, but one possible mechanism is attraction of spermatozoa to a factor(s) released from the egg. We have obtained evidence in favor of such a possibility by showing that human spermatozoa accumulate in follicular fluid in vitro. This accumulation into follicular fluid was higher by 30-260% than that observed with buffer alone and was highly significant (P less than 10(-8)). Not all of the follicular fluids caused sperm accumulation; however, there was a remarkably strong correlation (P less than 0.0001) between the ability of follicular fluid from a particular follicle to cause sperm accumulation and the ability of the egg, obtained from the same follicle, to be fertilized. These findings suggest that attraction may be a key event in the fertilization process and may give an insight into the mechanism underlying early egg-sperm communication.

The 30 Sv transported by the Florida Current through the Straits of Florida off Miami could consist of a wind-driven contribution of 17 Sv along with a thermohaline component of 13 Sv. The latter might flow from the South Atlantic as upper layer compensation for a net lower layer cross-equatorial flow southward. The Sverdrup transport along 24°N in the interior North Atlantic east of 55°–60°W is about 17 Sv, potentially matching the wind-driven component of the Florida Current. The circulation in the vicinity of 24°N and west of 55°–60°W up to the Bahama Banks contains energetic, shorter spatial scale flows, where there is a similarity between the regional pattern of the Sverdrup transport contours and the scales and structure of the observed C-shaped pattern of dynamic height.

Using altimetry data obtained from the Geosat Geodetic Mission (April 1985 to October 1986), low-frequency sea surface height (SSH) variations are investigated in the Gulf of Mexico. SSH time series are formed using the method of Fu and Chelton and are used to calculate surface geostrophic current vectors. Spatial patterns of SSH and current vector variations enable the tracking of two major rings shed from the Loop Current. The rings drifted southwestward across the gulf and into the western boundary region at an average speed of about 3.4 cm/s. The buildup of the Loop Current was monitored, as well as the appearance of an eddy of uncertain origin in the southwestern gulf. Verification of the Geosat results are provided with surface drifters, AVHRR imagery, and hydrography.

Geosat Exact Repeat Mission (ERM) altimetric measurements of the sea surface height in the Gulf of Mexico are used to determine the mean sea surface height with respect to the ellipsoid and mesoscale variability along Geosat ground tracks in the gulf for the time period from November 8, 1986 to November 25, 1988. A mean surface generated using the Geosat ERM along-track mean is calculated and contrasted with a previously derived mean surface determined using GEOS 3 and Seasat crossover differences. This provides a first look at the variability in the mean between the time periods of 1987-1988 and 1975-1978. In addition, the along-track mesoscale variability time series has been produced from the Geosat ERM data set by using a robust orbit-error removal algorithm to determine the variability of the sea-surface height with respect to the along-track mean. Good qualitative and quantitative agreement with previous in situ observations in the region is found. This study demonstrates the potential of satellite altimetry for oceanographic studies of the Gulf of Mexico.

The large variability of the Gulf of Mexico wind field indicates that high-resolution wind data will be required to represent the weather systems affecting ocean circulation. This report presents methods and results of the calculation of a corrected geostrophic wind data set with high temporal and spatial resolution. Corrected geostrophic wind was calculated from surface pressure analyses compiled by the Fleet Numerical Oceanography Center. The correction factors for wind magnitude and direction were calculated using linear regressions of observed Gulf buoy winds and geostrophic winds derived at the buoys. The regressions were performed for each month to determine the seasonal variability of the correction factors. The magnitude correction was found to be nearly constant (0.675) throughout the year, but the direction correction varied seasonally from 8.5 to 26.5 degrees. The corrected geostrophic wind was calculated twice daily store 1967–1982 on a spherical grid over the Gulf, together with the ...

Desertification can be a particularly visible consequence of climatic change. While considerable research has been devoted to terrestrial desertification in recent years, it is in the sea that biological deserts comprise 90% of the total area. Productive ocean ‘oases’ or coastal upwelling areas comprise less than .1% of the total ocean area but yield up to half the world's fish catch. Since these high productivity zones occur near coastal margins they are closest to man's pollution and his tools for species decimation. In this paper we examine the notion of biological deserts in the sea and assess the limitation of the ocean as a biological resource. Since climatic conditions favorable for above average ocean productivity are often conducive to the creation of coastal deserts, the connections between ocean and atmosphere in these regions are examined. Finally, the impacts of natural climatic and biological variability, marine pollution, and over-fishing on the process of biological desertification in the sea are explored.

The dynamics of the eddy shedding by the Loop Current in the Gulf of Mexico have been investigated using three nonlinear numerical models: two-layer, barotropic and reduced gravity. The barotropic and reduced gravity models demonstrate the individual behavior of the external and internal modes, and provide insight into how they interact in the two-layer model. Because of the economy of the semi-implicit free surface models, it was possible to perform over 100 experiments to investigate the stability properties of the Loop Current. Typically, the models were integrated 3–5 years to statistical equilibrium on a 1600 km×900 km rectangular domain with a resolution of 20 km×18.75 km. Prescribed inflow through the model Yucatan Channel was compensated by outflow through the Florida Straits. A long-standing hypothesis is that the Loop Current sheds eddies in response to quasi-annual variations in the inflow. We find that the Loop Current can penetrate into the Gulf, bend westward, and shed realistic ant...

We have sought to simulate and understand consistently observed features of the Somali Current system during the southwest monsoon using a two-layer, nonlinear numerical ocean model driven from rest by a uniform south wind in a flat bottom, rectangular geometry. High spatial resolution in both equatorial and coastal boundary regions was retained in this free-surface model. The model Somali Current is best classed as a time-dependent, baroclinic inertial boundary current. Analytical solutions to a quasi-steady linear model of the Somali Current are shown to be self-inconsistent with the linear approximation. While linear theory predicts perfect symmetry about the equator, the nonlinear numerical solutions exhibit marked asymmetries in less than a month as the model Somali Current becomes strongly inertial. By day 30 the current has attained its maximum value (140 cm s−1) within a few degrees of the equator, in accord with observations. In this time-dependent case, boundary layer separation occurs ...

The β effect is found to produce a poleward undercurrent in a wind-driven model of an eastern ocean circulation. The model is on an x, z plane and longshore derivatives of the velocity field are neglected. The nonlinear two-layer model is time-dependent and is solved numerically. Beta is found to exhibit little effect on the vertical mass transport, but exerts a dominant influence on the longshore flow by inducing a north-south sea surface slope. For an equatorward wind stress and flat bottom topography, the model predicts upwelling adjacent to the coast with a mean vertical velocity of 10−2 to 10−2 cm sec−1 and an e-folding width of about 15 km. The longshore flow is characterized by an equatorward surface jet and a poleward undercurrent. Outside the upwelling zone the longshore flow is weak. The offshore flow in the upper layer is slightly weaker than that predicted by Ekman drift. The compensating onshore flow in the lower layer is balanced by the north-south sea surface slope. Positive wind s...

Linear and nonlinear two-layer ocean circulation models of coastal upwelling on an f-plane are driven by time-dependent winds and solved numerically. Longshore variations in the circulation are neglected and offshore variations in the winds are specified. A technique for generating a realistic broad frequency-band wind stress from a kinetic energy spectrum of wind speed is developed. When results from the two models are compared, nonlinearities are found to be unimportant in explaining the basic upwelling dynamics. However, they do provide a mechanism for wave-wave interactions which broaden all spectral peaks. In the nonlinear model coherence-squared spectra between the winds and zonal current components in the upwelling zone indicate highest coherence at lowest frequencies for both layers, accompanied by a 180° phase shift from upper to lower layer at frequencies

The dynamics of the circulation in the Gulf of Mexico have been investigated using simple, efficient numerical models capable of simulating consistently observed dynamical features, including the Loop Current and the shedding of large anticyclonic eddies from the Loop. Over 150 model experiments were integrated to statistical equilibrium, typically 3–5 years. One popular hypothesis holds that the Loop Current sheds anticyclonic eddies in response to annual variations in the inflow through the Yucatan Straits. However, a striking result from the models is their ability to simulate the observed quasi-annual eddy shedding period with no time variations in the inflow. The model-predicted eddy diameters, amplitudes, and westward propagation speeds are also realistic. The dominant instability mechanism in the eddy shedding is a horizontal shear instability of the first internal mode, a barotrooic rather than a baroclinic instability. Therefore, a reduced-gravity model with one vertical mode is able to simulate the basic dynamics of the Loop Current-eddy system. Rossby-wave theory and a conservation of absolute vorticity trajectory analysis were used to explain the behavior of the Loop Current, including its northward penetration into the Gulf, the latitude of westward bending, the shedding period for the eddies, as well as their diameter, and their westward propagation speed. A regime diagram for the reduced-gravity model was constructed in terms of the Reynolds number Re and the beta Rossby number RB = vc/βLp2, where vc is the velocity at the core of the current, Lp is half the port separation distance and β is differential rotation. Eddy shedding can be prevented by reducing Re or by increasing RB. Bottom relief acts to inhibit baroclinic instability, yielding solutions more closely resembling those from the reduced-gravity model than the two-layer flat-bottom model. Topography also influences the paths of the shed eddies and, in the presence of sufficient deep water inflow through the Yucatan Straits, prevents Loop Current penetration, westward bending, and eddy shedding. In effect, the West Florida Shelf acts to reduce the port separation, increase RB, and shift the Loop Current into a stable regime. The signatures of barotropic and baroclinic instabilities in the two-layer Gulf of Mexico model were studied using upper and lower layer pressure fields and eddy-mean energetics. Both instability processes tend to drive a deep flow characterized by modon1 generation and they exhibit similar vertical phase relationships. However, in these experiments the westward propagation speeds associated with baroclinic instability are typically two to three times faster.

An eddy-resolving circulation model has been applied to the Gulf Stream System from Cape Hatteras to east of the Grand Banks (78-45 W, 30-48 N). The primitive equation model has realistic coastlines, bottom topography, and forcing functions. A two-layer version was driven by observed mean climatological wind forcing and mass transport prescribed at inflow. Outflow was determined by a radiation boundary condition and an integral constraint on the mass field in each layer. Specification of a Deep Western Boundary Current (DWBC) was included in some model runs. Results from a sequence of experiments suggest an important role for the DWBC in determining the mean path of the Gulf Stream and consequently the distribution of eddy kinetic energy, and the character of the deep mean flow. The most realistic experiment compares to within a factor of two or better with observations of the amplitude of eddy kinetic energy and rms fluctuations of the thermocline and sea surface height. Abyssal eddy kinetic energy was less than observed. The mean flow is characterized by recirculations to the north and south of the Gulf Stream and a deep cyclonic gyre just east of the northern portion of the New England Seamount Chain, as found in the data.

The Dynamical Ocean Forecasting Branch of NORDA is tasked with developing an ocean forecasting capability for the Navy using dynamical ocean models. In addition to model development, performance of this mission requires studies of ocean dynamics, ocean predictability, data assimilation, and oceanic prediction. The Gulf Stream is an important part of the system to be predicted. Approximately 1000 km east of Cape Hatteras, the Gulf Stream crosses the New England Seamount Chain. Observations presented by Richardson suggest that the New England Seamount Chain has a marked influence on the Gulf Stream. If so, this substantially complicates the Gulf Stream prediction problem. Some alternatives are to a) resolve the seamounts, b) parametrize the seamounts, or c) introduce data downstream to correct the field.In this study we use a simply two‐layer primitive‐equation model to study the influence of the New England Seamount Chain on the Gulf Stream. The model domain extends from Cape Hatteras to the Grand Banks an...

A numerical model is developed to simulate currents generated by hurricanes on the outer continental shelf and slope. Emphasis is on the mixed-layer response within a few hours of storm passage; however, some attention is given to the lower layer and shelf wave responses. The model is based on a layered, explicit, finite difference formulation using the nonlinear primitive equations including conservation of heat. The problem of topography intersecting the model layer is resolved by introducing artificial steps of the order of 100 m where the layer intersects the slope. Model comparisons are presented for three Gulf of Mexico hurricanes using a 0.2° grid. For two of the storms, the model reproduces better than 80% of the observed velocity variance with correlation coefficients of greater than 0.8 for the mixed layer. Discrepancies in the comparisons are traced to unresolved local topography and nonstorm forcing such as warm-core rings. Further model simulations reveal that (1) substantial shelf waves were generated with phase speeds of 4 to 10 m s−1, (2) the response is primarily baroclinic even in water as shallow as 200 m, (3) an entrainment law which scales with the velocity difference between the mixed layer and upper thermocline yields markedly better comparisons than one which scales with the wind stress, and (4) deviations from a straight-line storm path can significantly alter the response.

A primitive equation ocean model has been applied to the study of mesoscale ocean dynamics and prediction using sea surface height information derived from a satellite-borne altimeter. Results from a model of the Gulf of Mexico were directly compared with the altimeter data from GEOS 3 and Seasat reported by Marsh et al. (1984) and in situ hydrographic data analyzed by Maul and Herman (1985). In the eastern Gulf the amplitude and position of relative maxima of sea surface height variability were found to be similar for model, altimeter, and in situ data. In the central Gulf the model and the altimeter-derived sea surface height variability maps were similar but differed considerably from the in situ results. The mean sea surface in the model and from the in situ data also agreed well in the eastern Gulf, but there was little agreement in the central Gulf. While there is no geoid adequate for determining an independent altimetric estimate of the mean dynamic height of the sea surface in the Gulf by differencing the geoid with the altimeter-derived mean sea surface, the model dynamic mean sea surface can be subtracted from the mean surface of Marsh et al. (1984) to obtain a new estimate of the Gulf geoid, which may be the best geoid available in that region for several years. A benchmark experiment (“truth”) was integrated to statistical equilibrium and compared with results from four experiments in which the model was initialized with fields modified from archived benchmark data. The experiments differed only in the initialization fields. Each experiment was integrated for 100 days with inflow transport remaining constant throughout the integration. The idealized experiments were initialized geostrophically (1) with the exact sea surface and pycnocline height fields, (2) with only the exact sea surface heights and a pycnocline assumed to compensate it such that the deep pressure perturbations vanished, (3) just as in case 2 but with a geoid error component added on small spatial scales, and (4) just as in case 3 except the geoid error model included an additional contribution in strong geoid gradient regions. The sequence of four numerical experiments showed that (1) geostrophic initialization with exact sea surface and pycnocline height information provided accurate forecasts to 100 days, (2) even when only the sea surface height information was provided to the numerical model for geostrophic initialization and deep pressure perturbations assumed to vanish at the initial time, the forecasts were superior to persistence or climatology over the 100-day forecast period, and (3) errors in the geoid on spatial scales comparable to the grid resolution of the model did not seriously degrade the forecast, even in dynamically active regions with large gradients in the geoid height where instability processes were observed to occur.

The circulation of the western Indian Ocean is examined using a reduced-gravity model with one active layer and realistic basin geometry for the entire Indian Ocean north of 30°S. The Hellerman and Rosenstein monthly mean wind stress climatology is used to force the model. The numerical simulations reproduce the observed (Luyten and Roemmich, 1982) 26-day waves along the equator and the 50-day oscillations (Mysak and Mertz, 1984; Schott et al. 1988) between the equator and Madagascar. The 25- to 28-day oscillations of the model meridional velocity component agree with observed values of period, amplitude, wavelength, group velocity, and phase of the seasonal modulation. The model oscillations, which are excited in August and persist into February–March, are shown to be the result of Yanai waves generated between the western boundary and 50°E. During the southwest monsoon, the Yanai waves are initiated by a complex barotropic instability associated with the southern gyre. During the early stages of the northeast monsoon, the 26-day Yanai waves are generated by resonant forcing due to the intrusion into the equatorial waveguide of a standing, 800- to 900-km-wavelength meander of the eastward flow fed by the East African Coastal Current. Hence the simulation reveals that the 26-day oscillations in the equatorial Indian Ocean are excited by mechanisms significantly different than that believed to be responsible for the 20- to 30-day oscillations in the equatorial Atlantic and Pacific oceans. The numerical simulation also shows a 50-day oscillation between the equator and Madagascar west of 50°E. This periodicity is due to Rossby waves generated by a barotropic instability associated with the East African Coastal Current beginning about April each year. No evidence of the 50-day period oscillation is found in a corresponding linear simulation. Hence the barotropic instability of the oceanic currents in this region is offered as an alternative to direct wind forcing as the generating mechanism for the observed 40- to 60-day oscillations in the western Indian Ocean.

From 17 September to 10 October 1978 SEASAT made collinear passes over the Gulf of Mexico. Altimeter data for eight, three-day repeat passes over the eastern Gulf were examined using an arc-segment fitting technique to determine the mesoscale temporal variability of the sea surface. The pattern of sea height variability was then compared with sea height data generated by a numerical model of the Gulf (Hurlburt and Thompson, 1980) from the simulation of a complete cycle of Loop Current intrusion and shedding of an anticyclonic eddy. The model data was found to match that from the SEASAT altimeter when an anticyclonic eddy separated from the Loop Current and the Loop began to repenetrate into the eastern Gulf. Analysis of sparse ground truth data from ship-of-opportunity XBT's, satellite infrared imagery of the Loop Current boundary, and synthetic aperture radar (SAR) imagery, also from SEASAT, tend to confirm the circulation patterns deduced from the altimeter data and the numerical model. (Author)

A numerical model described and verified in part 1 of this two-part series (Cooper and Thompson, this issue) is applied to study the sensitivity of hurricane-generated currents on the outer shelf and slope. Numerical experiments are performed in a simple basin with a straight shelf. The sensitivity of the response to changes in storm parameters, direction of storm approach, and topography is quantified. Response is measured in terms of the mixed-layer velocity and depth at sites along the storm track. Results reveal the most important factors are (in decreasing order) wind speed, storm translation speed, direction of storm approach, asymmetry in the wind field, entrainment parameterization, and advection at slower storm translation speeds. Response is largely insensitive (less than 10%) to radius of maximum wind, shelf and slope configuration, bottom friction, atmospheric pressure gradients, and further reductions in the model grid size. For a storm approaching cross shelf, the response is primarily baroclinic (greater than 90%) and only weakly dependent (less than 10%) on the water depth at the site.

Intercomparisons are made among three sets of results for two regions of the Gulf Stream, upstream and downstream of the New England Seamount Chain (NESC): observational records from 12 inverted echo sounders with pressure gauges (IES/PGs), concurrent Geosat altimeter crossover point differences, and results from a primitive equation model of the region. Standard deviations of sea surface topography show generally good agreement for the three data sources. No significant difference between the upstream and downstream regions is observed in the actual data. IES/PG records and Geosat topographic variability have values of about 30 cm on both sides of the NESC, although model results show a discrepancy in the eastern region. Barotropic fluctuations account for about 30% of the total surface topographic variability and are only partially correlated with baroclinic fluctuations.