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As water miscible organic co-solvents are often required for enzyme reactions to improve e.g., the solubility of the substrate in the aqueous medium, an enzyme is required which displays high stability in the presence of this co-solvent. Consequently, it is of utmost importance to identify the most suitable enzyme or the appropriate reaction conditions. Until now, the melting temperature is used in general as a measure for stability of enzymes. The experiments here show, that the melting temperature does not correlate to the activity observed in the presence of the solvent. As an alternative parameter, the concentration of the co-solvent at the point of 50% protein unfolding at a specific temperature T in short c U 50 T is introduced. Analyzing a set of ene reductases, c U 50 T is shown to indicate the concentration of the co-solvent where also the activity of the enzyme drops fastest. Comparing possible rankings of enzymes according to melting temperature and c U 50 T reveals a clearly diverging outcome also depending on the specific solvent used. Additionally, plots of c U 50 versus temperature enable a fast identification of possible reaction windows to deduce tolerated solvent concentrations and temperature., (© 2024. The Author(s).)

Objective: Estimate prevalence and identify correlates of self-reported access to a gun among college students., Participants: Degree seeking students never serving in the military at 24 postsecondary institutions participating in ACHA-NCHA III during spring of 2020 and 2021 ( N  = 17,293) stratified by ciswomen, cismen, and transgender/gender nonconforming., Methods: Independent variables included measures of individual-level risk behaviors and experiences including interpersonal violence, mental health issues, and current and lifetime substance use. Individual-level demographics, indicators of institutional affiliation, and institutional characteristics used as controls. Descriptive statistics, chi-square tests of independence, and adjusted odds ratios are reported., Results: About 14% ( n  = 2,349) of sample self-reported access. Students' involvement with multiple different risk behaviors and experiences increased the odds of access., Conclusions: Access is a prerequisite to firearm use and resulting on-campus assaults, suicides, and homicides. Additional research on access prevalence, location and type of firearm being accessed, and the correlates of access is needed.

Over the last few years, the SARS-CoV-2 pandemic has made the need for rapid, affordable diagnostics more compelling than ever. While traditional laboratory diagnostics like PCR and well-plate ELISA are sensitive and specific, they can be costly and take hours to complete. Diagnostic tests that can be used at the point-of-care or at home, like lateral flow assays (LFAs) are a simple, rapid alternative, but many commercially available LFAs have been criticized for their lack of sensitivity compared to laboratory methods like well-plate ELISAs. The Capillary-Driven Immunoassay (CaDI) device described in this work uses microfluidic channels and capillary action to passively automate the steps of a traditional well-plate ELISA for visual read out. This work builds on prior capillary-flow devices by further simplifying operation and use of colorimetric detection. Upon adding sample, an enzyme-conjugated secondary antibody, wash steps, and substrate are sequentially delivered to test and control lines on a nitrocellulose strip generating a colorimetric response. The end user can visually detect SARS-CoV-2 antigen in 15-20 min by naked eye, or results can be quantified using a smartphone and software such as ImageJ. An analytical detection limit of 83 PFU/mL for SARS-CoV-2 was determined for virus in buffer, and 222 PFU/mL for virus spiked into nasal swabs using image analysis, similar to the LODs determined by traditional well-plate ELISA. Additionally, a visual detection limit of 100 PFU/mL was determined in contrived nasal swab samples by polling 20 untrained end-users. While the CaDI device was used for detecting clinically relevant levels of SARS-CoV-2 in this study, the CaDI device can be easily adapted to other immunoassay applications by changing the reagents and antibodies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objective: A review of the use of continuous IV infusion of anakinra; a description of the protocol for continuous IV infusion of anakinra in the treatment of cytokine storm developed over the past 4 years at a tertiary level academic medical center in the United States. Methods: We reviewed published reports of continuous IV infusion of anakinra in cytokine storm and summarize this method of treatment in other diseases. As well, over the past 4 years, continuous IV infusions of anakinra were administered at our tertiary level academic medical center in the United States (Regions Hospital, St. Paul, Minnesota) for approximately 400 patient days of treatment primarily for the cytokine storm associated with macrophage activation syndrome (MAS) in adults. This updated protocol is presented. While this a single center protocol, it may serve as an initial guide for further refinement of protocols in MAS and other conditions. Conclusion: Continuous IV infusion of anakinra has advantages over subcutaneous infusions and may be important in controlling severe life-threatening cytokine storm as seen in macrophage activation syndrome. This has the potential to be an important therapy for other syndromes including Cytokine Release Syndrome related to CAR T-cell therapy. Close collaboration between Rheumatology, Pharmacy and Nursing allows this treatment to be delivered rapidly and efficiently., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Saunders, Kuijpers, Sloan and Gertner.)

We report a new method for automated identification and measurement of primary particles within soot aggregates as well as the sizes of the aggregates and discuss its application to high-resolution transmission electron microscope (TEM) images of the aggregates. The image processing algorithm is based on an optimized Hough transform, applied to the external border of the aggregate. This achieves a significant data reduction by decomposing the particle border into fragments, which are assumed to be spheres in the present application, consistent with the known morphology of soot aggregates. Unlike traditional techniques, which are ultimately reliant on manual (human) measurement of a small sample of primary particles from a subset of aggregates, this method gives a direct measurement of the sizes of the aggregates and the size distributions of the primary particles of which they are composed. The current version of the algorithm allows processing of high-resolution TEM images by a conventional laptop computer at a rate of 1-2 ms per aggregate. The results were validated by comparison with manual image processing, and excellent agreement was found.

Permeable grass-covered surfaces can reduce the quantity of storm water runoff and filter out potentially harmful chemicals. The objective of this study was to develop permeable structural soils that sustained healthy turf growth and filtered heavy metals from contaminated pavement runoff. The basic soil medium was a 50:50 mixture (v/v) of expanded shale (ExSh) and quartz sand (QS). The ExSh component consisted of (i) large-diameter particles (3-6 mm), (ii) small-diameter particles (1-3 mm), or (iii) a 50:50 mixture (v/v) of the two. The basic blends were mixed with 0, 10, and 20% sphagnum peat moss (v/v) and 0, 10, and 20% natural zeolites (v/v) and placed in 15-cm-diameter pots in a greenhouse. Bermudagrass plugs were planted in each pot. The addition of sphagnum peat moss to the basic ExSh/QS blend increased bermudagrass growth and improved plant response to added fertilizer. Zeolites had no significant effect on plant growth in the absence of sphagnum peat moss. Growing mediums that contained 10 to 20% sphagnum peat moss and 10 to 20% zeolites consistently produced more bermudagrass biomass than the unamended ExSh/QS mixture. Changing the ratio of small- to large-diameter ExSh in the basic medium did not affect bermudagrass yield. Very low amounts of Cd, Cu, Pb, and Zn were recovered in leachate after the addition of 10 mg metal per pot, suggesting that most heavy metals (>99%) were retained in the growing mediums. Zeolites reduced the amount of Cd and Pb in leachate water, but not Cu or Zn.

The dissolution process for small, on the order of 1000 atoms, crystalline NaCl particles with defects embedded in highly supersaturated water vapor was studied by the molecular dynamics (MD) simulation method. We found that a breakdown of the crystal lattice does not occur unless (1) the thickness of water layer covering the surface of salt particles exceeds several molecular layers and (2) there are a considerable number of defects in the crystal. The collapse of the crystal lattice starts when the amount of water taken up by a salt particle reaches about half ( approximately 50%) of the amount of salt in this particle. The number of defects required to initiate subsequent dissolution of the NaCl crystal on the time scale accessible by our simulations ( approximately 40 ns) is in the range of 10 to 12%. We also report the estimates for the time required to form supersaturated aqueous solutions of NaCl from originally crystalline particles as a function of the number of defects in the crystal.

The diagnosis of neonatal sepsis is difficult, resulting in unnecessary treatment to minimize morbidity and mortality. We hypothesized that exposure to antenatal risk factors for sepsis alters the perinatal neutrophil phenotype. The study setting was a tertiary referral university-affiliated maternity and neonatal hospital. Neutrophils from adults, normal neonates, neonates with antenatal sepsis risk factors and their respective maternal samples were incubated alone, with agonistic Fas antibody or with lipopolysaccharide (LPS). Surface receptor CD11b expression and the percentage apoptosis (persistent inflammatory response) were assessed using flow cytometry. Both mothers and asymptomatic neonates exposed to maternal sepsis risk factors had increased spontaneous neutrophil apoptosis compared to their respective controls. Infants with sepsis were LPS and Fas hyporesponsive. Maternal neutrophils had a delay in apoptosis in all groups with enhanced LPS and Fas responses associated with neonatal sepsis. CD11b expression was not altered significantly between groups. Maternal neutrophil function is altered in neonatal sepsis and may have a diagnostic role. Neonatal sepsis was associated with LPS hyporesponsiveness, potentially increasing susceptibility to infection.

Systemic hypoxia-ischemia at birth may alter the neonatal neutrophil phenotype. In this study, we evaluated alterations in perinatal neutrophil phenotype following systemic hypoxia-ischemia compared with normal controls. Neutrophils from adults (n = 15), normal newborns (n = 20), newborns requiring resuscitation at birth (n = 17), and their respective maternal samples were incubated alone or with lipopolysaccharide (LPS). Surface receptor CD11b (neutrophil activation) and the percentage apoptosis (persistence of inflammatory response) were assessed using flow cytometry. Neutrophil apoptosis was decreased in neonates requiring resuscitation at birth and was further exaggerated in infants who developed mild neurological signs. All infants who required resuscitation were LPS hyporesponsive irrespective of neurological findings. Newborns with severe neurological signs had increased apoptosis and decreased CD11b. Maternal neutrophils were LPS hyporesponsive only if their infants had moderate/severe neurological signs. Infants with mild encephalopathy may display a predominantly proinflammatory neutrophil response with a persistent inflammatory response, whereas those with moderate/severe encephalopathy have a tendency toward immunosuppression.

We present a significantly improved set of complex indices of refraction (optical constants) for crystalline (NH(4))(2)SO(4) at 298 K, determined from extinction spectra measured in an aerosol flow tube (AFT). The improved values provide more accurate reproductions of experimental extinction spectra when used in light scattering calculations (Mie, T-matrix, etc.). Optical constants were also derived from measurements using a cryogenic AFT at 243, 223, and 213 K, temperatures characteristic of the upper troposphere and stratosphere. Only minor changes in the optical constants were observed down to 223 K, the transition temperature to the ferroelectric phase, after which significant changes were observed. Here we report the first complex indices of refraction at reduced temperatures for both phases of crystalline (NH(4))(2)SO(4).

This paper discusses the evaluation and application of a new generation of particulate matter (PM) emission factor model (MicroFacPM). MicroFacPM that was evaluated in Tuscarora Mountain Tunnel, Pennsylvania Turnpike, PA shows good agreement between measured and modeled emissions. MicroFacPM application is presented to the vehicle traffic on the main approach road to the Ambassador Bridge, which is one of the most important international border entry points in North America, connecting Detroit, MI, with Windsor, Ontario, Canada. An increase in border security has forced heavy-duty diesel vehicles to line up for several kilometers through the city of Windsor causing concern about elevated concentrations of ambient PM. MicroFacPM has been developed to model vehicle-generated PM (fine [PM2.5] and coarse < or = 10 microm [PM10]) from the on-road vehicle fleet, which in this case includes traffic at very low speeds (10 km/h). The Windsor case study gives vehicle generated PM2.5 sources and their breakdown by vehicle age and class. It shows that the primary sources of vehicle-generated PM2.5 emissions are the late-model heavy-duty diesel vehicles. We also applied CALINE4 and AERMOD in conjunction with MicroFacPM, using Canadian traffic and climate conditions, to describe the vehicle-generated PM2.5 dispersion near this roadway during the month of May in 2003.

We describe an inversion method for determining the composition, density, and size of stratospheric clouds and aerosols by satellite remote sensing. The method, which combines linear least-squares minimization and Monte Carlo techniques, is tested with pure synthetic IR spectra. The synthetic spectral data are constructed to mimic mid-IR spectra recorded by the Improved Limb Atmospheric Spectrometer (ILAS-I and ILAS-II) instruments, which operate in the solar occultation mode and record numerous polar stratospheric cloud events. The advantages and limitations of the proposed technique are discussed. In brief we find that stratospheric aerosol in the size range from 0.5 to 4.0 02114 microm can be retrieved to an accuracy of 30%. We also show that the chemical composition of common stratospheric aerosols can be determined, whereas identification of their phases from mid-IR satellite remote-sensing data alone appears to be questionable.

The application of wavelet filtering and analysis in spectroscopy is discussed in relation to the analysis of complex atmospheric spectra, where contributions from condensed phase particles and gas phase molecules are present in the form of broad-band features and narrow lines, respectively. The broad-band contribution can be extracted as the 'smooth signal' component of the wavelet transform, with a large reduction in the size of the corresponding data files. This procedure is applied to an investigation of the H2SO4 aerosol content of a series of atmospheric spectra measured in the ATMOS missions. The sulfate content of the smooth signal is analysed by means of correlation techniques, using a set of laboratory reference spectra of varying sulfuric acid concentration and temperature. Correlation density maps and correlation curves are used to select the most appropriate spectral zones for sulfate analysis and to assess the sulfate aerosol content in the atmosphere subsequent to the eruption of the Mount Pinatubo volcano.

Complex refractive indices of supercooled liquid water at 240, 253, 263, and 273 K, and ice at 200, 210, and 235 K in the mid infrared from 460 to 4000 cm(-1) are reported. The results were obtained from the extinction spectra of small (micron-size) aerosol particles, recorded using the cryogenic flow tube technique. An improved iterative procedure for retrieving complex refractive indices from extinction measurements is described. The refractive indices of ice determined in the present study are in good agreement with data reported earlier. The temperature region and range of states covered in the present work are relevant to the study of upper tropospheric and stratospheric aerosols and clouds.

An inversion method for the characterization of atmospheric condensed phases from infrared (IR) spectra is described. The method is tested with both synthetic IR spectra and the spectra of particles that flow in a cryogenic flow tube. The method is applied to the IR spectra recorded by the Atmospheric Trace Molecule Spectroscopy instrument carried by the Space Shuttle during three missions in 1992, 1993, and 1994. The volume density and particle size distribution for sulfate aerosol are obtained as a function of altitude. The density and size distribution of ice particles in several cirrus clouds are also retrieved. The probable radius of the ice particles in the high-altitude (10-15-km) cirrus clouds is found to be approximately 6-7 microm.

Micron-sized water droplets in a cryogenic flow tube were probed by IR spectroscopy. The analysis of the IR spectra suggests that there is a relative increase of about 30% in the fraction, f(L), of low density domains in water on cooling over the temperature range between 300 and 240 K. The results derived from the experiments agree qualitatively with those of molecular dynamics (MD) simulations in terms of the increase in the f(L) values. The MD simulations show that the intensities of the mode at about 100 cm(-1) for the molecules in the low density domains are reduced in comparison to the average, while the intensities and frequencies of the librational mode at 600 cm(-1) are increased. Furthermore, the reorientations (dielectric relaxation times) in these domains are found to be somewhat slower, pointing to the fact that these low density "cages" live longer than the average local molecular environments in supercooled water.

Biosolids applications can significantly increase Hg concentrations in cultivated soils. The objective of this study was to quantify levels of mercury in soils and runoff from a biosolids-amended watershed. The study site was a terraced, cultivated watershed that received cumulative biosolids loadings of 0, 87, or 224 Mg ha(-1) between 1974 and 1993. Snowmelt runoff samples were collected from the three treatment areas in the spring of 1995. Soils were collected along transects from the 0 and 224 Mg ha(-1) biosolids treatment areas at depths of 0 to 15 and 15 to 30 cm. Mercury analysis of stored, freeze-dried biosolids samples showed that Hg concentrations during the 20-year study ranged from 12.4 mg kg(-1) initially to 2.4 mg kg(-1) near the end. Soil Hg concentrations were elevated in the surface (0-15 cm) and subsurface (15-30 cm) of the 224 Mg ha(-1) biosolids-treated terrace relative to the control. Mercury concentrations in the 0- to 15-cm soil depth ranged from 30 to 50 microg kg(-1) for the control terrace and 180 to 390 microg kg(-1) for the 224 Mg ha(-1) biosolids-treated terrace. Concentrations were lower in the 15- to 30-cm depth. Total Hg concentrations in snowmelt from the control terrace ranged from 9.2 to 27.9 ng L(-1) and 19.8 to 44.8 ng L(-1) for the biosolids-treated terraces. Most Hg was associated with particulates > 0.45 microm. Mercury concentrations were elevated in grass tissue growing near the watershed's runoff lagoon.

We describe the most recent implementation of the data acquisition system which we have developed for fast time-resolved (FTR) Fourier transform spectroscopy (FTS) and report spectra that were obtained by using this instrument. This FTRPTS data system operates in conjunction with any continuous-scan Michelson interferometer, giving it the capability to record many time-delayed spectra of a transient event, with a minimum time resolution of 1 µs. The sensitivity and the spectral resolution of the complete system are the same as those that would be obtained if the interferometer were used in conventional steady-state spectroscopy. To illustrate the performance of the FTRPTS system, we recorded emission spectra from the products of transient chemical reactions of H atoms with CF(3)Cl, CF(2)Cl(2), CFCL(3), and NO(2). These are laser-initiated reactions involving atoms with energies that correspond to a temperature of approximately 27,000 K and lifetimes of a few microseconds, but the FTRPTS system records the time evolution of their products with high signal-to-noise ratio.

Has awareness of the alcoholic beverage warning label reached its maximum? This study tracks changes in the level of awareness among a sample of 7334 inner-city African-American gravidas seeking prenatal care between May 1989 and June 1993. Previously, we found that a significant increase in awareness of the warning label occurred in March 1990. In the current analysis over a 50-month period, the level of awareness continued to increase through December 1992 and then leveled off, suggesting a negatively accelerated growth function. The logistic function fitted to the awareness curve predicts that the upper limit of awareness in this population has been reached (the predicted upper limit being 81.5%). In addition a logit regression analysis showed that women who did not know about the warning label were more likely to be over 29 years of age. Heavier drinkers were 1.25 times more likely to be aware of the label. Among those drinkers who were not aware of the label, 30% drank at both conception and antenally, thus putting their fetus at high risk for alcohol-related birth defects.

Objective: We compared the impact of the Federal Alcoholic Beverage Warning Label on multiparae (women with at least one previous live birth) and nulliparae (women with no previous live births). The label, implemented on November 18, 1989, urges women not to drink during pregnancy because of the risk of birth defects. If multiparae drank during prior pregnancies, delivering apparently normal babies, we hypothesized that the warning might be less salient for them., Method: We studied 17,456 inner city black gravidas seen between September 1986 and September 1993 at one antenatal clinic. Time series analysis (ARIMA) examined trends in monthly means of antenatal drinking scores (alcohol consumption adjusted for weeks' gestation, age, parity and periconceptional drinking)., Results: For nulliparae (n = 7,349), reported drinking began to show a significant decline in June 1990, 7 months after the implementation of the warning label (t = 2.00, p < .04). In contrast, multiparae (n = 10,107) showed no change in reported drinking (t = 1.23) postlabel., Conclusions: Given previous results that multiparae drink more and that heavier drinkers are ignoring the warning label, these data are very distressing and suggests the importance of targeting multiparae for intensive prevention efforts.

This article presents data on the awareness of the alcohol beverage warning label among a sample of 5,169 inner city African-American gravidas seeking prenatal care. While the label law was implemented in November 1989, a significant increase in knowledge of the label did not occur until March 1990. Women who predominantly consumed wine coolers and beer, and those under age 30 were more likely to know about the label than their counterparts.

In a sample of over 12,000 African-American gravidas, we tested the hypothesis that the Federal Beverage Labeling Act of 1988 has decreased antenatal drinking. Results of time series analysis indicated a 7-month lag in the impact of the alcohol warning label. Controlling for population changes, antenatal drinking began to fall as of June 1990. However, this decrease was small in size and did not impact on the heaviest drinkers. Seasonal trends in drinking were also detected, with peaks around the end of the year and the summer.