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Introduction: This study examines the association between hospital volume and all-cause mortality in Black women with triple negative breast cancer (TNBC) who received surgery and chemotherapy. Methods: Black women ages 18+ with stage I-III TNBC who received both surgery and chemotherapy were identified in the National Cancer Database (NCDB). Hospital volume was determined using the number of annual breast cancer cases divided by the number of years the hospital participated in the NCDB. Hospital annual volume quartiles ranged from Q1(lowest) to Q4(highest). Univariable analysis and multivariable logistic regression modeling with restricted cubic splines examined the effect of hospital volume on all-cause mortality. Results: Sixteen thousand five hundred fifty-six patients met the study criteria. All-cause mortality incidence was lower at higher volume compared to lower volume hospitals Q124.1% (95% CI: 22.8 to 25.4), Q221.8% (95% CI: 20.5 to 23.1), Q320.9% (95% CI: 19.6 to 22.1), Q419.0% (95% CI: 17.7 to 20.1), p<0.001. On multivariable analysis, treatment at the highest hospital volume quartile was associated with a 21% reduction in the odds of death compared to the lowest quartile [Q4Vs. Q1, OR=0.79 (95% CI: 0.67 to 0.92)]. For every 100-patient increase in annual volume, all-cause mortality was reduced by 4% [OR=0.96 (95% CI: 0.94 to 0.98)]. There was a significant linear dose-dependent relationship between increasing hospital volume and all-cause mortality. Conclusion: Black women treated at high-volume hospitals have lower all-cause mortality than those at low-volume hospitals. Future studies should examine the characteristics of high-volume hospitals associated with improved outcomes.

ABSTRACTThe betwixt and in-between spaces in urban environments help define the zeitgeist. In transforming liminal spaces into memorials, public art provides an opportunity to assert the voice of the people and helps to catalyze social change. In recent years, the informal and formal claiming of urban liminal spaces has been central to the Black Lives Matter (BLM) movement. This article explores the use of informal placemaking and how claiming liminal space can lead to transformative social reactions for sustained social change in subtle and direct ways. By situating asphalt art within the cultural activism literature where “art, activism, performance, and politics meet, mingle and interact” (Verson, 2007, p. 172), one of the roles of asphalt art can be understood. Existing scholarship in this area “has focused on the role of creative practices such as culture jamming, subversion, public art, performance, and rebel clowning” (Buser et al., 2013, p. 606). This article considers the relationship between asphalt art’s creative praxis in the processes of urban placemaking and how meaning is constructed in urban space that presents opportunities for new political, social, and cultural dialogues to resonate the causes some liminal spaces represent that bring activities and existing narratives that develop new civic narratives.

Cahen Rotagg was a young illustrator growing up in France, she would actually stop breathing in order to draw perfect lines. After years of these oxygen-deprived efforts, she had a [...]

Every day, the venerable Merriam-Webster lexicon source posts a different word and its meaning on its website as the 'word of the day.' Comparably, men and women report to fire [...]

Supercritical carbon dioxide (sCO2) power cycles show promising potential of higher plant efficiencies and power densities for a wide range of power generation applications such as fossil fuel power plants, nuclear power production, solar power, and geothermal power generation. sCO2 leakage through the turbomachinery has been one of the main concerns in such applications. To offer a potential solution, we propose an Elasto-Hydrodynamic (EHD) seal that can work at elevated pressures and temperatures with low leakage and minimal wear. The EHD seal has a very simple, sleeve-like structure, wrapping on the rotor with minimal initial clearance at µm levels. In this work, a proof-of-concept study for the proposed EHD seal was presented by using the simplified Reynolds equation and Lame's formula for the fluid flow in the clearance and for seal deformation, respectively. The set of nonlinear equations was solved by using both the conventional Prediction-Correction (PC) method and modern Physics-Informed Neural Network (PINN). It was shown that the physics-informed deep learning method provided good computational efficiency in resolving the steep pressure gradient in the clearance with good accuracy. The results showed that the leakage rates increased quadratically with working pressures and reached a steady state at high-pressure values of 15 ~ 20 MPa, where Q = 300 g/s at 20 MPa for an initial seal clearance of 255 µm. This indicates that the EHD seal could be tailored to become a potential solution to minimize the sCO2 discharge in power plants.

EHMT1 (also known as GLP) is a multifunctional protein, best known for its role as an H3K9me1 and H3K9me2 methyltransferase through its reportedly obligatory dimerization with EHMT2 (also known as G9A). Here, we investigated the role of EHMT1 in the oocyte in comparison to EHMT2 using oocyte-specific conditional knockout mouse models (Ehmt2cKO, Ehmt1cKO, Ehmt1/2cDKO), with ablation from the early phase of oocyte growth. Loss of EHMT1 in Ehmt1cKO and Ehmt1/2cDKO oocytes recapitulated meiotic defects observed in the Ehmt2cKO; however, there was a significant impairment in oocyte maturation and developmental competence in Ehmt1cKO and Ehmt1/2cDKO oocytes beyond that observed in the Ehmt2cKO. Consequently, loss of EHMT1 in oogenesis results, upon fertilization, in mid-gestation embryonic lethality. To identify H3K9 methylation and other meaningful biological changes in each mutant to explore the molecular functions of EHMT1 and EHMT2, we performed immunofluorescence imaging, multi-omics sequencing, and mass spectrometry (MS)–based proteome analyses in cKO oocytes. Although H3K9me1 was depleted only upon loss of EHMT1, H3K9me2 was decreased, and H3K9me2-enriched domains were eliminated equally upon loss of EHMT1 or EHMT2. Furthermore, there were more significant changes in the transcriptome, DNA methylome, and proteome in Ehmt1/2cDKO than Ehmt2cKO oocytes, with transcriptional derepression leading to increased protein abundance and local changes in genic DNA methylation in Ehmt1/2cDKO oocytes. Together, our findings suggest that EHMT1 contributes to local transcriptional repression in the oocyte, partially independent of EHMT2, and is critical for oogenesis and oocyte developmental competence.

This year, Firehouse Expo runs Oct. 8-12, 2019 in Nashville, TN. During the week, attendees will have the chance to experience more than 250 exhibitors on the show floor, gain [...]

A response to issues raised by Martin De Nys in the article 'Conceiving Divine Transcendence' dealing with Hegel's 'God: A Counterfeit Double?'. The focus is especially on the question of religious representation, issue of autonomy of philosophy, issue of creation, actual practice of Hegel in the Lectures on the Philosophy of Religion, and Hegel as a contemporary resource for philosophical theology.

Paper spray ionization mass spectrometry (PS-MS) offers a rapid alternative platform requiring no sample preparation. Aerosolized CWA simulants, trimethyl phosphate, dimethyl methylphosphonate, and diisopropyl methylphosphonate, were captured by passing air through a glass fiber filter disk and simultaneously capturing it directly onto a disposable paper spray cartridge. CWA simulants were aerosolized at varying concentrations using an in-house built aerosol chamber. A custom 3D-printed holder was designed and built to facilitate the aerosol capture onto the paper spray cartridges. The air flow through each of the collection devices was maintained equally to assure the same volume of air sampled across methods. Each approach yielded linear calibration curves with R2 values between 0.98–0.99 for each compound and similar limits of detection in terms of disbursed aerosol concentration. While the glass fiber filter disk has a higher capture efficiency (≈40%), the paper spray method produces analogous results even with a lower capture efficiency (≈1%). Improvements were made to include glass fiber filters as the substrate within the paper spray cartridge consumable. Glass fiber filters were then treated with ammonium sulfate to decrease chemical interaction with the simulants. This allowed for improved direct aerosol capture efficiency (>40%). Ultimately, the limits of detection were reduced to levels comparable to current worker population limits of 1x10-6 mg/m3.

•Diverse plant species are used to treat predominant diseases in forest fringe communities.•Medicinal plants contribute 64 % of the gross annual income of forest fringe communities.•Local population had the same opinion about the main drivers of loss of medicinal plants.•Insitu and exsitu conservation approaches are central to sustainable medicinal plant use.•Challenges to the extraction and use of medicinal plants are closely linked to their location.

Paper spray mass spectrometry has been shown to successfully analyze chemical warfare agent (CWA) simulants. However, due to the volatility differences between the simulants and real G-series (i.e., sarin, soman) CWAs, analysis from an untreated paper substrate proved difficult. To extend the analytical lifetime of these G-agents, metal–organic frameworks (MOFs) were successfully integrated onto the paper spray substrates to increase adsorption and desorption. In this study, several MOFs and nanoparticles were tested to extend the analytical lifetimes of sarin, soman, and cyclosarin on paper spray substrates. It was found that the addition of either UiO-66 or HKUST-1 to the paper substrate increased the analytical lifetime of the G-agents from less than 5 min detectability to at least 50 min.

Sustainable water management is paramount to ensuring continued access to fresh water resources. Some states have chosen to use analytical solutions to predict pumping-induced drawdowns and the reduction in groundwater baseflow to streams in an effort to predict negative impacts associated with high volume groundwater withdrawals (HVGWs). In line with this approach, the State of Michigan has developed the Water Withdrawal Assessment Tool (WWAT), which estimates streamflow depletion to evaluate whether a proposed HVGW activity will have an adverse impact on stream ecology. To assess the tool's performance, this study compared calculations for streamflow depletion estimated using the Hunt (1999) solution, as implemented in the WWAT, with those of a numerical groundwater flow model developed in MODFLOW for two different locations in Michigan where HVGW wells have been permitted. In addition, sensitivity and uncertainty analyses were conducted. The results showed that the WWAT, in general, provides a conservative estimate of stream depletion. However, to obtain a more accurate estimate, the type of aquifer (unconfined versussemi-confined) needs to be taken into account. The most critical parameters are the storativity, S, and the streambed conductance, λ. Since Shas a fixed value of 0.01 in the WWAT, the role of streambed conductance becomes paramount. Given the paucity of information regarding λ, its estimation merits additional scrutiny.

The concept of fitness has widened as we've entered the '90s. America's annual health care costs per capita may reach approximately $5,551 by the year 2000. It's been estimated the [...]

The key to a better back is balanced muscle conditioning. Back' is one of those good news, bad news words in the English language. It's a word that is usually [...]

The dissolution rate of nonaqueous phase liquid (NAPL) often governs the remediation time frame at subsurface hazardous waste sites. Most formulations for estimating this rate are empirical and assume that the NAPL is the nonwetting fluid. However, field evidence suggests that some waste sites might be organic wet. Thus, formulations that assume the NAPL is nonwetting may be inappropriate for estimating the rates of NAPL dissolution. An exact solution to the Young‐Laplace equation, assuming NAPL resides as pendular rings around the contact points of porous media idealized as spherical particles in a hexagonal close packing arrangement, is presented in this work to provide a theoretical prediction for NAPL‐water interfacial area. This analytic expression for interfacial area is then coupled with an exact solution to the advection‐diffusion equation in a capillary tube assuming Hagen‐Poiseuille flow to provide a theoretical means of calculating the mass transfer rate coefficient for dissolution at the NAPL‐water interface in an organic‐wet system. A comparison of the predictions from this theoretical model with predictions from empirically derived formulations from the literature for water‐wet systems showed a consistent range of values for the mass transfer rate coefficient, despite the significant differences in model foundations (water wetting versus NAPL wetting, theoretical versus empirical). This finding implies that, under these system conditions, the important parameter is interfacial area, with a lesser role played by NAPL configuration. Exact solution to the Young‐Laplace equation for pendular ringsTheoretical determination of the mass transfer rate coefficient under hydrophobic conditionsPredicts similar NAPL dissolution rates for oil‐wet and water‐wet conditions

Objective:A Center for Health Equity that included a primary care practice was built in a neighborhood affected by long-term disparities related to race and class in order to promote health equity within the population. Changes in blood pressure and HbA1c (glycated hemoglobin) over 2 years were examined to assess the impact of providing culturally appropriate and patient-centered care. Methods:Data from June 1, 2012, to June 30, 2014 were obtained. Patients with high blood pressure or elevated HbA1c levels were treated according to evidence based guidelines. Blood pressure and HbA1c values at the first and last visit were compared using paired ttests. Results:Of the 390 patients seen with a systolic pressure ≥140 mm Hg, 358 came back for at least 1 visit (92%). By the time of the last visit, 70% had values <140 mm Hg. Mean decreases for systolic and diastolic pressure between the first and last visit were statistically significant (both P< .001). Of the 88 patients seen with HbA1c values ≥7%, 68 came back for at least 1 visit (77%). By the last visit, 31% had values <7%. The change in mean HbA1c levels between the first and last visits was statistically significant (P= .001). Conclusion:Data from this report demonstrate statistically significant improved clinical outcomes among members of this community who sought and received care from physicians within this Center for Health Equity.

The article discusses the importance of the divestiture aspect of the defense acquisition life-cycle model in the U.S. Army. Topics covered include potential value engineering and better buying power savings from divestiture, the difference between divestiture and simple disposal and examples of cost savings strategies used in the divestiture of the Mine Resistant Ambush Protected (MRAP) vehicle deployed in Iraq and Afghanistan.

Objective. To determine the factor structure of the Illness Intrusiveness Rating Scale in young adults with only allergies versus those with both allergies and asthma to evaluate the domains of impairment associated with these 2 chronic health conditions. Method. A total of 454 young adults with allergies (n = 255) or asthma + allergies (n = 199) between the ages of 18 and 25 (mean = 19.39, standard deviation = 1.34) completed the study questionnaire as a part of a larger study of the psychosocial adjustment of young adults with a chronic health condition. Results. A 3-factor structure (Identity, Intimacy, and Relationships and Personal Development) of the Illness Intrusiveness Rating Scale had better fit than a 1-factor structure. Several modifications to the original 3-factor model improved the fit within this population. Conclusions. The 3-factor model was shown to be effective within young adults with allergies and asthma + allergies with some modifications. The structure of the final model was not invariant across the disease groups, although most of the items (excluding health and religious expression) performed similarly between those young adults with allergies and those with asthma + allergies.

Abstract:What contributes to persistent trends of Black male educational underachievement? Past literature has often used a deficit-informed framework to answer this question, portraying Black male students as incapable, unintelligent, disadvantaged, and at-risk to fail, feeding into negative stereotypes. In this article, our primary objective is to depart from this deficit-informed orientation, seeking out themes that speak to, and explain, Black male resiliency while discussing major developments in research on Black college men in both PWIs and HBCUs. We aim to fill gaps in existing research by using a more heuristic framework, one that may guide future research on Black male collegiate experiences and success by drawing upon resilience theories.

The sit-up remains the definitive exercise for abdominal strengthening, instructors must deviate from conventional abdominal exercise to challenge participants with innovative movements. Whatever the creative movement, our goal should be [...]

We conducted a PHABSIM study on Bingham Creek, Washington, by using validated habitat suitability criteria for the rearing of coho salmon Oncorhynchus kisutch. We compared the relationship between weighted usable area (WUA) and flow with a previously determined empirical relationship that showed increasing coho salmon smolt production with increasing summer low flow (). The relationship between juvenile coho salmon WUA and flow indicated that the greatest amount of habitat occurred at a flow that was lower than our low-flow measurement, and the amount of habitat decreased with increasing flow. Thus, PHABSIM results were contrary to empirical measurement of coho salmon smolt production. Based on the relationship between summer flow and smolt production, production of smolts would decline if flow was reduced to the flow that maximizes WUA. The failure of PHABSIM to be consistent with empirical results may have be related to habitat suitability being influenced more by the numerous subdominant, schooling juvenile coho salmon and less by the dominant, territorial individuals, which have higher survival and prefer higher velocities.

Data with some values below a limit of detection (LOD) can be analyzed using methods of survival analysis for left-censored data. The reverse Kaplan-Meier (KM) estimator provides an effective method for estimating the distribution function and thus population percentiles for such data. Although developed in the 1970s and strongly advocated since then, it remains rarely used, partly due to limited software availability.

The goal of the present study was to quantify the population-based background serum concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by using data from the reference population of the 2005 University of Michigan Dioxin Exposure Study (UMDES) and the 2003-2004 National Health and Nutrition Examination Survey (NHANES).

Recognition of peptide antigen by T cells involves coordinated movement of T cell receptors (TCRs) along with other costimulatory and signaling molecules. The spatially organized configurations that result are collectively referred to as the immunological synapse. Experimental investigation of the role of spatial organization in TCR signaling has been facilitated by the use of nanopatterned-supported membranes to direct TCR into alternative patterns. Here we study the mechanism by which substrate structures redirect TCR transport. Using a flow-tracking algorithm, the ensemble of TCR clusters within each cell was tracked during synapse formation under various constraint geometries. Shortly after initial cluster formation, a coordinated centripetal flow of ∼20nm/s develops. Clusters that encounter substrate-imposed constraint are deflected and move parallel to the constraint at speeds that scale with the relative angle of motion to the preferred centripetal direction. TCR transport is driven by actin polymerization, and the distribution of F-actin was imaged at various time points during the synapse formation process. At early time points, there is no significant effect on actin distribution produced by substrate constraints. At later time points, modest differences were observed. These data are consistent with a frictional model of TCR coupling to cytoskeletal flow, which allows slip. Implications of this model regarding spatial sorting of cell-surface molecules are discussed.

The article describes the preservation of the original detail and artistic content of the Tarbert House in Kerry, Ireland. Tarbert House is an 18th century mansion created by James Leslie in the 1750s. The Leslie Family settled at the mansion after the Williamite wars. The mansion originally had two floors of seven bays. Its facades feature watercolors created by English artist John Charles Barrow, which can be dated from 1795. The north front of the mansion features a cut-stone door case of dressed stone with an entablature. Some of the artistic works that can be found in the mansion are portraits of Bishop Leslie of Limerick, and a portrait of Sir Edward Leslie.

Presents letters to the editor on key issues of interest to the automobile industry, compiled as of September 2005. Emergence of Toyota as the world automotive financial powerhouse; Comparison of the Ford GT and Ferrari; Characteristics of rear/front/all-wheel-drive cars.

Faced with the challenge of replacing an existing Art Deco arch bridge, the city of Columbus, Ohio, decided against replication in favor of constructing a new aesthetic symbol for the city. The proposed Main Street Replacement Bridge, a bridge consisting of a single-ribbed arch inclined at a 10-degree angle, will gracefully span the Scioto River and will provide the city with its new aesthetic symbol, as well as provide the final link between new parkway developments on both banks of the river. The original design concept was abandoned because of increasing construction complexities compounded by a decreasing budget allowance. With a client committed to aesthetic design, a requirement for a less complicated erection process, and a shortened construction timeline, the engineers were challenged to redesign the bridge within the revised budget while maintaining the intriguing geometry of the previous bridge design. How the design team overcame the new design challenges and, specifically, the redesign of the arch geometry, the reshaping and redesign of the pedestrian and vehicular decks, the redesign of the lateral bracing of the inclined arch, and the complete overhaul of the bridge piers, is described.

N-[(3-fluorophenyl)methyl]glycyl-N-[3-[((3-aminophenyl)sulfonyl)- 2-(aminophenyl)amino]-(1S,2S)-2-hydroxy-1-(phenylmethyl)propyl]- 3-methyl-L-valinamide (DPC 681, DPC(1)) on oral coadministration with ritonavir (RTV) in rats caused a significant increase in systemic exposure to DPC. Following a single oral dose of [(14)C]DPC with and without RTV pretreatment in rats, and subsequent analysis of whole-body sections, prepared at 1 and 7 or 8 h postdose, using whole-body autoradiography showed an increase in radioactivity in tissues (e.g., brain, and testes) upon coadministration. The distribution of radioactivity in the brain parenchyma and ventricles was different, such that the concentration of radioactivity was greater in cerebrospinal fluid (CSF) than in central nervous system. Thus, the use of CSF concentration of the total radioactivity as a surrogate for brain penetration would result in an overestimation. DPC was determined to be metabolized prominently by rCYP3A4. The increased tissue exposure to DPC in rats could largely be attributed to inhibition of CYP3A1/2 by RTV. DPC was also a good substrate for P-glycoprotein (Pgp), with K(m) of 4 microM and V(max) of 13 pmol/min. The Pgp-mediated transport of DPC across Caco-2 cells was readily saturated at >or=10 microM and was inhibited significantly by RTV at 5 to 10 microM. The data above and the reported RTV concentrations suggested that both the Pgp and CYP3A4 inhibition by RTV may play a significant role in enhancing the systemic and tissue exposure to DPC in humans.

AbstractWe determined depth and velocity preference curves for juvenile coho salmon Oncorhynchus kisutchfor input into the physical habitat simulation system of the instream flow incremental methodology. Preferences were determined by scaling the maximum value of the ratio of observed use to expected use to 1.0. We developed composite preference curves by compiling weighted preferences for depth and velocity from four separate studies. The values of depth and velocity preference determined in each of the four studies were weighted by the sample size of the study, summed for each depth or velocity interval, and then normalized such that the sums peaked at 1. Juvenile coho salmon showed maximum preference for depths of 76–100 cm and velocities of 3–6 cm/s. To test the composite preference curves, we used an independent data set, marking the locations of juvenile coho salmon and comparing the products of preferences for depth and velocity (Pref (dv) = Pref (d) · Pref (v), where Pref (d) is depth preference and Pref (v) is velocity preference) where coho salmon were observed with those at measurement points on a grid. In June and September 1996, most coho salmon were found most frequently at locations with high combined preferences.

The presence of surfactants may have profound effects on the transport of organic contaminants in multiphase systems. It is a common practice, however, to model the subsurface migration of liquids independently of the aqueous phase composition. As such, transport in these systems may not be adequately characterized. This study investigates the impact of pH on interfacial tension, wettability, and the drainage capillary pressure–saturation relationship in air–water–quartz and o‐xylene–water–quartz systems containing dodecylamine, an organic base. In these systems, three mechanisms, speciation, partitioning, and sorption, are important in determining the interfacial tension and contact angle, and consequently, important in determining the capillary pressure. By adjusting the pH above and below, the pKaof the base, the relative importance of these mechanisms was altered. Below dodecylamine's pKaof 10.6, the base was primarily in a cationic form resulting in minimal partitioning into the nonaqueous liquid and greater sorption at the quartz surface. Above the pKa, the base was primarily in a neutral form which did not sorb to the quartz, and, furthermore, partitioned into the organic liquid phase where its surface activity was minimized. The combination of these processes caused the capillary pressure to change in a manner consistent with pore‐scale theory of capillarity. The utility in this approach lies in the possibility of predicting transport properties in multiphase systems while incorporating the direct effects of solution chemistry.

Tetrachloroethylene has been used in the manufacture of vinyl‐lined asbestos cement pipe installed in water distribution systems in certain New England communities. Tetrachloroethylene was used as a solvent for Piccotex, a vinyl‐toluene α‐methyl styrene co‐polymer, which was then sprayed on the interior of the finished asbestos cement pipe. The migration of tetrachloroethylene through the vinyl lining was modeled as a diffusive process in which the diffusion coefficient was an exponential function of concentration. The parameters of the model were found by fitting a numerical solution of the diffusion equation to data from laboratory experiments involving the evaporation of tetrachloroethylene from a Piccotex layer. The conclusion was reached that significant quantities of tetrachloroethylene may be leached into the water supply for a time period on the order of years.

β-Cyclodextrin and γ-cyclodextrin chiral bonded phases were previously shown to be useful in the separation of enantiomers, diastereomers and structural isomers. In this work it is demonstrated that these stationary phases are also useful in more routine separations. As such, they provide an alternative to the popular reverse phase packings. Because the selectivity of cyclodextrin packings is often unique they can be used to compliment conventional columns, particularly when separating complex mixtures where peak overlap is a problem. The separation of several important classes of compounds is used to demonstrate the general utility of this packing.

Many studies of transport through soil assume that the laboratory columns used in the experiments are packed homogeneously. This research evaluated a variety of dry and wet packing techniques for their ability to produce uniform packings of clean sands without the use of specialized equipment. The best dry packing technique consisted of the deposition of 0.2‐cm layers followed by compaction with a metal pestle. For the sand used in this study, this technique resulted in a porosity of 0.325 ± 0.0020. The best wet packing technique consisted of the deposition of thin layers of saturated sand into water while vibrating the column. This technique resulted in a denser and more uniform packing, with the porosity equaling 0.315 ± 0.0018. No significant lateral particle‐size segregation was observed for either technique. Despite their success in producing homogeneous columns, the techniques proved time consuming, taking about 1 h per 5 cm of packed depth to pack a 15‐cm square column.

Purpose. This report summarizes the identification of nine deamidation and four hydrolysis products from a sample of pramlintide injection final drug product that was subjected to stress at 40°C for 45 days. Methods. The pramlintide degradation products were isolated by strong cation exchange HPLC followed by reversed-phase HPLC. Subsequent to isolation, the molecular weight of each component was determined by liquid chromatography-mass spectrometry (LC/MS). Further characterization was accomplished by amino acid sequence analysis and/ or enzymatic (thermolysin) digestion followed by LC/MS and sequence analysis. Results. The isolated products were identified as [iso-Asp21]-pramlintide, [iso-Asp3]-pramlintide, and [iso-Asp22]-pramlintide, the deamidation products of pramlintide with rearrangement at Asn21, Asn3, and Asn22, respectively. Also found were [Asp/iso-Asp14]-pramlintide, and [Asp/iso-Asp35]-pramlintide, the deamidation products at Asn14, and Asn35, and [Asp21]-pramlintide together with [Asp22]-pramlintide. For the deamidations at the 14thand 35thresidues, it could not be determined whether the substance corresponded to the Asp or the iso-Asp product. The [Asp21] and [Asp22] products could not be separated from each other chromatographically but were both identified in a single fraction. Two minor degradation products were also identified as deamidated species. However, the sites of deamidation remain unknown. Also identified were [l-18]-pramlintide, [l-19]-pramlintide, [19-37]-pramlintide, and [20-37]-pramlintide, the products of hydrolytic peptide backbone cleavage at amino acids His18/Ser19and Ser19/Ser20, respectively. One other product was isolated and tentatively identified as a cyclic imide intermediate preceeding deamidation. Conclusions. The primary mode of thermally induced degradation for this peptide is deamidation. A second degradation mechanism is peptide backbone hydrolysis.

The effectiveness of employing stationary phases composed of chemically bonded cyclodextrin molecules in the high performance liquid chromatographic separation of a variety of different types of compounds is summarized. Over one hundred compounds, including optical, geometrical, and structural isomers, diastereomers, and epimers were successfully separated from each other via use of beta- or gamma-cyclodextrin bonded phases and aqueous methanolic mobile phases. The mechanism of separation is based upon inclusion complex formation between the compounds being separated and the cyclodextrin molecules bonded to the stationary phase. The effects of temperature, mobile phase composition and flow rate upon the chromatographic selectivity and resolution are described. The results indicate that the cyclodextrin columns may be more versatile, flexible, and effective compared to the conventional normal or reversed phase columns.

Hydrogen depth profiles, obtained by a nuclear reaction technique, have been investigated in a series of glow-discharge deposited Si specimens. These include undoped films, homogeneously doped n- and p-type specimens, junctions and continuously graded devices. It is shown that the hydrogen concentration CH in the bulk of the specimens depends systematically on the doping level and thus on the position of the Fermi energy ∊F in the mobility gap. In junctions there exists an almost linear dependence of Ch on (∊c-∊f)o, extending over a range of about 6 at.%. The lowest values of CH (1-2 at.%) occur in p+ regions. The results are discussed and it is suggested that, with the good depth resolution obtainable, hydrogen profiling may be a useful approach for the study of barrier profiles in a-Si devices. In addition to the bulk effects, the doping dependence of CH at the surface and the specimen-substrate interface has been investigated.

A systematic study of angular momentum dissipation in deep-inelastic heavy ion collisions is carried out by combining two experimental methods: the angular correlation ofα particles and protons in coincidence with deeply inelastic light fragments; and the first two moments of theγ-ray multiplicity. The unified analysis of these data, using a quantum mechanical treatment of the particle anisotropies and statistical decay calculations, yields most probable fragment spinsI0=10.8±1.1ħ and 13.4±1.1ħ for58Ni and62Zn, respectively, close to the sticking limit. For the width of the vector spin distribution assumed in our analysis to be equal in all three directions we obtainσ=3.9±1.3 ħ and 2.9±1.8ħ for58Ni and62Zn, respectively. These values correspond to most probable alignment parameters 〈Pzz〉=0.66±0.19 and 0.82±0.17 for58Ni and62Zn, respectively. As only very few partial waves of this light system undergo deep-inelastic scattering,σ directly relates to spin fluctuations, and is compared to asymptotic values from transport theories.

As the nation's infrastructure ages, many older bridges face rehabilitation or replacement. Many of these structures have historical significance, and others have become community landmarks. Distinctive metal truss bridges and various concrete arch bridges still grace the nation's highways, but they are rapidly disappearing because they cannot meet the safety requirements of modern highway usage. As a result, where roadway and river crossings were once defined by expressive, sometimes monumental spans that made the passage truly an experience, travelers now speed efficiently over unobtrusive structures, often unaware they were ever on a bridge. Engineers are becoming increasingly aware of the undercurrent of public sentiment for preserving these links to the past. Opposition to replacement can delay needed improvements for months and even years, but it can be overcome by incorporating the existing bridge into alternative solutions that meet both the functional needs and the aesthetic desires of the community. When an older bridge is to be part of the new crossing solution, what are the aesthetic considerations for the bridge designer or the project manager? The aesthetic impact of various alternative solutions involving older bridges is discussed, including compatibility of parallel structures when different bridge types are involved, importance of viewpoints, and aesthetic impact of various preservation measures such as cathodic protection. In addition, guidelines are provided and examples of various solutions are shown.