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Background Reproducing populations of invasive carps (Hypophthalmichthys spp.) could alter aquatic food webs and negatively affect native fishes in the Mississippi National River and Recreation Area (MISS) and the St. Croix National Scenic Riverway (SACN). However, proposed invasive carp barriers may also threaten populations of native migratory fishes by preventing movements of fish between rivers that are necessary for life history requirements. In this study, nonlethal chemical techniques were used to provide baseline data related to the condition, trophic position, and migratory histories of lake sturgeon (Acipenser fulvescens) captured in the Mississippi and St. Croix Rivers. Results Fish length and weight measurements and age estimates determined from pectoral fin rays demonstrated that lake sturgeon from the Mississippi River had greater lengths-at-age compared to sturgeon from the St. Croix River. However, length–weight relations were similar for sturgeon from the Mississippi and St. Croix Rivers. Lake sturgeon captured from different locations had distinguishable fatty acid signatures, and stable isotope analyses demonstrated that lake sturgeon from the Mississippi River generally feed at a higher trophic level than those in the St. Croix River. Strontium-to-calcium ratios (Sr:Ca) from fin ray cross sections indicated that sturgeon captured from the Mississippi River had higher Sr:Ca values than sturgeon captured from the St. Croix River, and natal origins and capture locations were not significantly different among sturgeon captured within individual rivers. Most sturgeon were captured in water with a similar Sr:Ca signature as their natal waters, indicating that there is some separation between populations of lake sturgeon in the St. Croix and Mississippi Rivers. However, Sr:Ca data indicated substantial variation in movement patterns among individual lake sturgeon, indicating that populations interact through migrations of individual fish between rivers. Conclusions Study results provide baseline condition and food web structure index data for assessing changes in lake sturgeon populations should invasive carps become established in these areas of the Mississippi and St. Croix Rivers. Controlled-exposure and telemetry studies would help verify and enhance the relations between Sr:Ca signatures in water and lake sturgeon pectoral fin rays to further assess mixing of sturgeons between rivers.

Understanding the quantity and form of nutrient loads to large lakes is necessary to understand controls over primary production, phytoplankton community composition and the production of phytotoxins. Nutrient loading estimates to large lakes are primarily made at stream gages that are deliberately placed outside the direct influence of lake processes, but these estimates cannot take into account processes that occur in the biologically active river-to-lake transition zone. These transition zones (rivermouths) sometimes alter nutrient concentrations and ratios substantially, but few studies have directly measured processing rates of nutrients within rivermouths. From April through September 2016, we conducted 23 water column incubation experiments to measure nutrient loss rates in four rivermouths. First order loss rates (K) for inorganic nitrogen (N) and phosphorus (P) indicated greater loss in light than in dark treatments, suggesting primary production increases N and P removal. Variability in K was high across both time and space, and the measured environmental parameters did not appear to be strongly associated with this variation in K for most N and P forms. If the measured K values and water residence times are accurate, then between 0 and 99% of the inorganic P and nitrates entering the rivermouth would be lost (i.e., converted to organic or particulate P). In late summer, Fox River discharge is low and residence times are usually long, which allow for much higher proportional nutrient removal in the water column. Water column processing appears to be capable of transforming large quantities of dissolved N and P to particulate forms and thus altering its transport and presumably its bioavailability.

Large lakes provide a variety of ecological services to surrounding cities and communities. Many of these services are supported by ecological processes that are threatened by the increasing prevalence of cyanobacterial blooms which occur as aquatic ecosystems experience cultural eutrophication. Over the past 10 yr, Lake Erie experienced cyanobacterial blooms of increasing severity and frequency, which have resulted in impaired drinking water for the surrounding communities. Cyanobacterial blooms may impact ecological processes that support other services, but many of these impacts have not been documented. Secondary production (production of primary consumers) is an important process that supports economically important higher trophic levels. Cyanobacterial blooms may influence secondary production because cyanobacteria are a poor-quality food resource and cyanotoxins may be harmful to consumers. Over 3 yr at 34 sites across the western basin of Lake Erie, we measured three indices of secondary production that focus on the dominant bivalve taxa: (1) growth of a native unionid mussel, (2) the size of young-of-year dreissenid mussels, and (3) the mass of colonizing animals on a Hester-Dendy sampler. Associations between these indices and cyanobacterial data were estimated to assess whether cyanobacteria are associated with variation in secondary production in the western basin of Lake Erie. The results suggest cyanobacterial abundance alone is only weakly associated with secondary production, but that cyanotoxins have a larger effect on secondary production. Given recurring late-summer cyanobacterial blooms, this impact on secondary production has the potential to undermine Lake Erie's ability to sustain important ecosystem services.

The availability of growth data in N. norvegicus is important for management purposes due to a lack of aging criteria and the commercial importance of fisheries in this species. Growth varies as a function of stock density, hence comparisons of growth rates between stocks at known density is particularly valuable. Growth is also related to starting size in males, making raw data on size-specific growth rates more valuable. Internally injected passive tags allowed us to track the growth of male and female individuals over one or two years. The spatial position of tagged recaptures was recorded to measure site fidelity of tagged releases. A total of 3300 pots were fished and their spatial positions were recorded to enable Catch Per Unit Effort calculations. Similarly, spatially geo-referenced v-notching and notched recovery enables spatially gridded densities to be calculated. Finally, acoustic mapping was carried out both on and off the fishing ground and was ground-truthed with sedimentology from grabs at 22 stations. These data are useful for fisheries and macroecological studies., Design Type(s)observation design • organism development design • longitudinal study designMeasurement Type(s)growth • habitatTechnology Type(s)observational methodFactor Type(s)geographic location • biological sex • notchedSample Characteristic(s)Nephrops norvegicus • Ireland • ocean biome Machine-accessible metadata file describing the reported data (ISA-Tab format)

Invasion of North American waters by nonnative Dreissena polymorpha and D. rostriformis bugensis has resulted in declines of the Unionidae family of native North American mussels. Dreissenid mussels biofoul unionid mussels in large numbers and interfere with unionid movement, their acquisition of food, and the native mussels' ability to open and close their shells. Initial expectations for the Great Lakes included extirpation of unionids where they co-occurred with dreissenids, but recently adult and juvenile unionids have been found alive in several apparent refugia. These unionid populations may persist due to reduced dreissenid biofouling in these areas, and/or due to processes that remove biofoulers. For example locations inaccessible to dreissenid veligers may reduce biofouling and habitats with soft substrates may allow unionids to burrow and thus remove dreissenids. We deployed caged unionid mussels (Lampsilis siliquoidea) at 36 sites across the western basin of Lake Erie to assess spatial...

Objectives This study conducted a prospective, single-arm, multicenter trial to evaluate the safety and efficacy of ultrasound-facilitated, catheter-directed, low-dose fibrinolysis, using the EkoSonic Endovascular System (EKOS, Bothell, Washington). Background Systemic fibrinolysis for acute pulmonary embolism (PE) reduces cardiovascular collapse but causes hemorrhagic stroke at a rate exceeding 2%. Methods Eligible patients had a proximal PE and a right ventricular (RV)-to-left ventricular (LV) diameter ratio ≥0.9 on chest computed tomography (CT). We included 150 patients with acute massive (n = 31) or submassive (n = 119) PE. We used 24 mg of tissue-plasminogen activator (t-PA) administered either as 1 mg/h for 24 h with a unilateral catheter or 1 mg/h/catheter for 12 h with bilateral catheters. The primary safety outcome was major bleeding within 72 h of procedure initiation. The primary efficacy outcome was the change in the chest CT–measured RV/LV diameter ratio within 48 h of procedure initiation. Results Mean RV/LV diameter ratio decreased from baseline to 48 h post-procedure (1.55 vs. 1.13; mean difference, −0.42; p Conclusions Ultrasound-facilitated, catheter-directed, low-dose fibrinolysis decreased RV dilation, reduced pulmonary hypertension, decreased anatomic thrombus burden, and minimized intracranial hemorrhage in patients with acute massive and submassive PE. (A Prospective, Single-arm, Multi-center Trial of EkoSonic® Endovascular System and Activase for Treatment of Acute Pulmonary Embolism (PE) [SEATTLE II]; NCT01513759 )

Purpose: To evaluate retrospectively the safety profile and clinical success of ultrasound-accelerated thrombolysis for acute pulmonary embolism (PE) with a standard lytic infusion protocol. Materials and Methods: A retrospective study was performed at a single center treating patients with acute PE between October 2009 and April 2012. On diagnosis of submassive or massive PE by pulmonary computed tomography angiography or ventilation/ perfusion scan, all patients received anticoagulation and treatment using the EkoSonic endovascular system (EKOS Corporation, Bothell, Washington). The ultrasound-accelerated thrombolytic infusion catheters were placed into the affected pulmonary arteries to facilitate administration of recombinant tissue plasminogen activator at 0.5‐1.0 mg/h/catheter. Results: Treatment of 60 patients (35 men, 25 women; age 61 y 16; 53 bilateral PE; 48 submassive PE) resulted in complete thrombus clearance (Z 90%) in 57% and near-complete (50%‐90%) clearance in 41% of patients after infusion of 35.1 mg 11.1 of recombinant tissue plasminogen activator over 19.6 hours 6.0. Measurements before and after treatment showed a decrease in pulmonary artery pressure (47 mm Hg 15 to 38 mm Hg 12 [systolic], P o .001) and Miller score (25 3t o 17 6, P o .001). There were 57 patients who survived to discharge. All three patients who died in the hospital presented with massive PE. On 90-day follow-up, 56 patients (93%) were alive. Conclusions: The current study demonstrates effectiveness and safety of ultrasound-accelerated thrombolysis in patients with acute PE with a large thrombus burden.

The natural amino acids are primarily helix breakers at the low assignment temperatures characteristic of many studies, but recent genomic analyses of thermophilic proteins suggest that at high temperatures, some breakers may become strong helix formers. Moreover, the breaker/former inventory has not been previously characterized at the physiologically relevant temperature of 37°C. The versatility of 13CO NMR chemical shifts as helicity reporters allows construction of two mutant peptide series, tailored to expand the range of temperature assignments for helical propensities and derived from the core hosts tL-Ala9XxxAla9-tL and tL-AlaNva4XxxNva4Ala9-tL, Nva = norvaline. For three limiting guests Xxx, the helix former Nva and the breakers Gly and Pro, we report wXxx[T] assignments at seven temperatures from 2 to 80°C, validating our reasoning and paving the way for assignment of a definitive wXxx[T] data-base. © 2008 Wiley Periodicals, Inc. Biopolymers 91: 311–320, 2009. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com

Measured at 2 degrees C in water, NMR chemical shifts of (13)C=O labeled central alanine residues of peptides W-Lys(5)-(t)L(3)-Ala(n)-(t)L(3)-Lys(5)NH(2), n = 9, 11, 13, 15, 19 and W-Lys(5)-(t)L(3)-a-Ala(n)-A-Inp-(t)L(2)-Lys(5)NH(2) (a = D-Ala; (t)L = tert-leucine; Inp = 4-carboxypiperidine) are used to assign jt(L) and ct(L), the N- and C-terminal (t)L capping parameters and length-dependent values for w(Ala)(n), the alanine helical propensity for Ala(n) peptides. These parameters allow Lifson-Roig characterization of the stabilities of Ala(n)() helices in water. To facilitate chemical shift characterization, different (13)C/(12)C ratios are incorporated into specific Ala sites to code up to six residue sites per peptide. Large left/right chemical shift anisotropies are intrinsic to helical polyalanines, and a correcting L-R-based model is introduced. Capping parameters jt(L) = ct(L) lie in the range of 0.3 to 0.5; the (t)L residues are thus moderately helix-destabilizing. For helical conformations of lengths shorter than eight residues, assigned values for w(Ala) approach 1.0 but increase monotonically with length to a value of 1.59 for w(Ala)(19).

The helicity reporting parameters t/c and [theta](222) have been measured at 2, 25, and 60 degrees C in water for the solubilized polyalanine series Ac-Hel-A(n)-(t)LInp(2)K(4)W-NH(2) of length 4or = nor = 14 that bears the helix-initiating and monitoring N-cap Ac-Hel and the spaced solubilizer (t)LInp(2)K(4)W-NH(2) as a C-cap. Correlation of t/c with length shows that the helical propensity for nor = 6 is ca. 1.0, consistent with our early reports, but that a dramatic increase in temperature dependence and helical propensity occurs for nor = 8. A model based on hydrogen-bonding cooperativity is proposed to explain this finding, and both t/c and [theta](222) are modeled successfully by length-dependent alanine propensities at 2 degrees C of 1.03 for n = 6, 1.15, for 7or = nor = 9 and 1.26 for nor = 10. The implications of these results for the energetics of helix formation by alanine-rich peptide sequences are discussed.

The logical design principles behind a system of properly water-solubilized, spaced polyalanines are presented. Peptides conforming to these design principles are shown to be unaggregated, and their helical properties as measured by the circular dichroism (CD) residue ellipticity at 222 nm, [theta](222), are shown to be dependent upon the lengths of their alanine regions. It is further demonstrated that CD contributions of the alanine cores are independent of the CD contributions attributable to other features of the peptides. The CD response of these polyalanines to variations in temperature and salt or denaturant concentration is described. CD data for a series of peptides with Ala(n) cores varying in length from 12 to 45 residues are presented that allow calculation of the helical propensity, w(Ala), in a purely alanine context. Mathematical modeling of these unprecedented data reveals the insufficiency of currently accepted literature helicity modeling parameters. A modification to the standard Lifson-Roig algorithm is introduced based on hydrogen-bonding cooperativity.

A family of efficient helix-initiating N-terminal caps X-Hel is introduced that expand the scope and versatility of the previously reported reporting conformational template Ac-Hel, (Kemp, D. S.; Allen, T. J.; Oslick, S. J. Am. Chem. Soc. 1995, 117, 6641-6657) and a working principle for predicting cap performance is described, based on structurally specific intramolecular hydrogen bond formation. Replacement of the N-acetyl by urethane, urea, or sulfonamide generated less efficient polypeptide helix inducers. The N-formyl cap is found to be equivalent to the N-acetyl and may provide more convenient quantitative helix reporting properties. Anionic N-caps derived from the series X = (-)O(2)C-(CH(2))(n)-CO, 0or = nor = 3, are superior to N-acetyl, as are N-acylglycyl and N-acyl-beta-aspartyl. The latter pair of caps permit introduction of the X-Hel functionality within a polypeptide chain, allowing control of helicity of a peptide sub-sequence. Applications of these capping functions are discussed. This work has been focused primarily on immediate practical goals directed toward enhancing the maximum helicity of isolated short to medium-sized peptides in aqueous solution, but its developing concepts and working hypotheses are likely to significantly enhance our understanding at a chemical level of the protein folding problem.

Isolating spacers introduced between solubilizing lysine regions and a polyalanine core permit rigorous characterization of context-free alanine helices. The preferred building blocks for isolating spacers are amino acids with rigid, extended conformations such as proline, isonipecotic acid, and tert-leucine. Replacing isolating spacers by conventional N- and C-caps dramatically increases the helicity of dodecaalanine. Solubilized, isolated polyalanines provide optimal tools for testing polypeptide helicity algorithms, central to resolution of the protein folding problem.

β-Amino alanine is shown to stop helix propagation in a polyalanine context while effectively stabilizing the resulting C-terminus. Structural evidence is provided by circular dichroism and t/c ratios from the reporting conformational template Ac-Hel.

This study examines factors associated with the high attrition rate in treatment programs for men who batter. In accord with past research, we expected demographic variables of age, race, employment status, relationship status, and socioeconomic status to predict attrition. We also hypothesized that attitudinal and personality variables, as well as contextual/program variables, might account for attrition more parsimoniously. Specifically, we hypothesized that attrition would be predicted by frequency and severity of violence, denial of a problem with violence, rigidity of thinking, low levels of self-disclosure, and higher anxiety and constriction in social situations. In addition, we predicted attrition would relate to dependency, maladaptive personality styles, and expectations regarding group counseling (e.g., whether treatment is perceived as aversive). Finally, we proposed that attrition would relate to whether batterer participation in treatment was self-motivated or the result of external pressures. Participants were 61 men enrolled in a batterer treatment program in a mid-sized city. Analyses of variance and discriminant analyses indicated that program attrition was unrelated to demographic, attitudinal, or personality variables. Only the contextual/program variables of mileage traveled to attend and external monitoring of attendance significantly differentiated treatment rejecters, drop-outs, and treatment continuers. Findings are discussed with regard to intrinsic and extrinsic motivational factors. Future directions for exploration are discussed.

Peptides containing N-α-benzoyl-cis-4-amino-L-proline are shown to adopt γ-turn conformations in chloroform solutions.

Background: The present study documents the use of carbon tracking to localize parathyroid adenomas in three patients with persistent or recurrent parathyroid disease. Methods: Three patients requiring second or third operations for hyperparathyroidism were operated upon after the parathyroid lesion had been localized preoperatively using a suspension of carbon particles in water. The enlarged parathyroid glands were identified by using one or more of the following: computed axial tomography, magnetic resonance imaging, ultrasound or Sestamibi nuclear scan. The lesion was then localized with ultrasound or computed axial tomography and a carbon track was inserted from the lesion to the skin, leaving a small skin tattoo as a marker for the surgeon. Each patient underwent a minimally invasive parathyroid operation. Results: For each of the three patients the recurrent or persistent parathyroid adenoma was successfully identified and removed via a small incision. Conclusion: Minimally invasive techniques for primary hyperparathyroidism are changing our approach to parathyroid surgery. However, a minimally invasive technique is less applicable when the disease is persistent or recurrent. Although, when the recurrent or persistent parathyroid adenoma can be identified, localization and carbon tracking have proved useful in allowing the surgeon to remove the lesion via a minimally invasive technique.

When the superintendent of the Lawrence Public Schools decreed that test scores must be raised, the district added two time-consuming test- preparation programs to the curriculum. Mr. Vogler and Mr. Kennedy recall the difficult choices that their school had to make in order to accommodate the additions to an already-crowded schedule. WITH FEAR, apprehension, and foreboding, we opened our morning papers. Were they in there? Sure enough, the test results were right on the front page. As we quickly scanned the results for the Massachusetts Comprehensive Assessment System (MCAS) for 2000, our fears were confirmed. Once again, our school system was ranked last in the state, the third year in a row. Today, one of the most controversial issues in public education is the use of standardized tests as the focal point of state accountability programs, specifically, the use of state-mandated, high-stakes tests. The most vocal opposition to such testing programs has focused not so much on the tests themselves but on the "high stakes" attached to the outcomes. These high stakes sometimes involve incentives, such as cash awards to schools or individual teachers whose students demonstrate high levels of performance. But they have also taken the form of the public reporting of test results, the prevention of grade-to-grade promotion and high school graduation, and the possible takeover of schools that continue to demonstrate low levels of student performance. Although the debate surrounding high-stakes testing programs continues, the reality for most public school administrators, teachers, parents, and students is that the tests are here, they do count, in some cases students must pass them to graduate, and in almost all cases the quality of a school system will be judged by how well students perform on the tests. In public school systems where students perform well, the results will be taken as "proof" that the schools are providing a high- quality education. But what happens to a public school system in which the students don't perform well on these tests? Are these schools not providing a high-quality education? What is a poor-performing school system to do? As a teacher and a former teacher in the Lawrence (Mass.) Public Schools, we have the dubious distinction of having been part of a school system that ranked either last or second to last in terms of student performance on the MCAS in every year since the test scores were reported to the public. But before we discuss the programs implemented to improve the students' MCAS scores, we'd like to offer some background on the community, the student population, and the Lawrence public school system. * Although there is a strong regional economy, Lawrence is the 23rd- poorest community in the country with a population of more than 50,000. Its unemployment rate in 2001 was 8.8%. * The most recent waves of immigrants to the city are from the Caribbean, Central and South America, and Southeast Asia. * Forty-three percent of adults in Lawrence did not finish high school. * Eighty percent of parents in Lawrence identify a language other than English as the primary language used in their homes. * The pre-K-12 student population of 12,562 is 86% minority (primarily Latino); the district has the highest percentage of Latino students in the state. * Seventy-seven percent of the students enrolled in the Lawrence Public Schools live below the federal poverty level. * About one-third of the students receive some form of federal assistance. * Almost one-third of the students drop out. * The Lawrence Public Schools have had five superintendents in the last eight years (two were interim). * Lawrence has the only nonaccredited public high school in Massachusetts. Our current superinten-dent, a former administrator in the New York City schools, is quite familiar with high-stakes testing programs (the Regents Examinations). …

Regiospecific binding of perchlorate ions to the N-terminus of short-chained template-substituted polyalanine sequences in water dramatically increases helicity.

Relative C-capping propensities for nonpolar amino acids and the primary amide, which control helicity for many small peptides, have been determined by a new method. Practical consequences of the observed propensities and their temperature dependences are discussed.

Assigned from data sets measured in water at 2, 25, and 60 degrees C containing (13)C=O NMR chemical shifts and [theta](222) ellipticities, helical propensities are reported for the 20 genetically coded amino acids, as well as for norvaline and norleucine. These have been introduced by chemical synthesis at central sites within length-optimized, spaced, solubilized Ala(19) hosts. The resulting polyalanine-derived, quantitative propensity sets express for each residue its temperature-dependent but context-independent tendency to forego a coil state and join a preexisting helical conformation. At 2 degrees C their rank ordering is: PGHC, T, NSY, F, WV, DKQIR, MLEA; at 60 degrees C the rank becomes: H, PGCR, KT, Y, FN, VSQW, DI, MEAL. The DeltaDeltaG values, kcal/mol, relative to alanine, for the cluster T, N, S, Y, F, W, V, D, Q, imply that at 2 degrees C all are strong breakers: DeltaDeltaG(mean) = +0.63 +/- 0.11, but at 60 degrees C their breaking tendencies are dramatically attenuated and converge toward the mean: DeltaDeltaG(mean) = +0.25 +/- 0.07. Accurate modeling of helix-rich proteins found in thermophiles, mesophiles, and organisms that flourish near 0 degrees C thus requires appropriately matched propensity sets. Comparisons are offered between the temperature-dependent propensity assignments of this study and those previously assigned by the Scheraga group; the special problems that attend propensity assignments for charged residues are illustrated by lysine guest data; and comparisons of errors in helicity assignments from shifts and ellipticity data show that the former provide superior precision and accuracy.

Anunprecedented, highdegreeofhelicity as judged by CD spectroscopy is observed in N-templated model peptides of the type AcHel-(Ala4Lys)nAla2-NH2 (AcHel-Ala peptide pictured; AcHel is an N-terminal helix-inducing template for polypeptides). These results raise concern over the current methods for determining 100 % helicity.

Length-dependent helical propensities w(Ala)(n,T) at T = 10, 25, and 60 degrees C are assigned from t/c values and NMR 13C chemical shifts for series 1 peptides TrpLys(m)Inp2(t)Leu-Ala(n)(t)LeuInp2Lys(m)NH2, n = 15, 19, and 25, m = 5, in water. Van't Hoff analysis of w(Ala)(n,T) show that alpha-helix formation is primarily enthalpy-driven. For series 2 peptides Ac-Trp Lys5Inp2(t)Leu-(beta)AspHel-Ala(n)-beta-(t)LeuInp2Lys5NH2, n = 12 and 22, which contain exceptionally helical Ala(n) cores, protection factor-derived fractional helicities FH are assigned in the range 10-30 degrees C in water and used to calibrate temperature-dependent CD ellipticities [theta](lambda,H,n,T). These are applied to CD data for series 1 peptides, 12or = nor = 45, to confirm the w(Ala)(n,T) assignments at T = 25 and 60 degrees C. The [theta](lambda,H,n,T) are temperature dependent within the wavelength region, 222 +/- 12 nm, and yield a temperature correction for calculation of FH from experimental values of [theta](222,n,T,Exp).

NMR and CD studies are reported for two length series of solubilized, spaced, highly helical polyalanines that are N-capped by the optimal helix stabilizer (beta)Asp-Hel and C-capped by beta-aminoalanine beta and that are studied in water at 2 degrees C, pH 1-8. NMR analysis yields a structural characterization of the peptide Ac(beta)AspHelAla(8)betaNH(2) and selected members of one (beta)AspHelAla(n)beta series. At pH > 4.5 the (beta)AspHel cap provides a preorganized triad of carboxylate anion and two amide residues that is complementary to the helical polyalanine N-terminus. The C-terminal beta-aminoalanine assumes a helix-stabilizing conformation consistent with literature precedents. H(N)CO NMR experiments applied to capped, uniformly (13)C- and (15)N-labeled Ala(8) and Ala(12) peptides define Ala(n) hydrogen bonding signatures as alpha-helical without detectable 3(10) character. Relative NH-->ND exchange rates yield site protection factors PF(i) that define uniquely high fractional helicities FH for the peptide Ala(n) regions. These Ala(n) calibration series, studied in water and lacking helix-stabilizing tertiary structure, yield the first (13)C NMR chemical shifts, (3)J(HNH)(alpha) coupling constants, and CD ellipticities [theta(Molar)](lambda,n) characteristic of a fully helical alanine within an Ala(n) context. CD data are used to assign parameters X and [theta](lambda,infinity), required for rigorous calculation of FH values from CD ellipticities.

A two-state helix-coil model underlies all calculations of fractional helicities FH from CD spectra of helical polypeptides. The presence of an isodichroic point near 203 nm is widely assumed to validate this model, but is shown here to provide inadequate validation for alanine-rich peptides. A parametric correlation with constant slope B between CD ellipticities at a pair of wavelengths is introduced as a more rigorous two-state test. Correlations of temperature-dependent [theta](222) vs [theta](208) values are reported for a variety of peptides. Constant slopes B are observed for literature CD data obtained from fragments of helical proteins and dimeric helical coiled coils, but parametric correlations of CD data for alanine-rich peptides consistently exhibit anomalous concave upward curvature, characterized by local slopes that are linearly temperature dependent. Low-temperature CD studies together with parametric correlations at a series of wavelengths demonstrate that the curvature anomaly is maximal at 222 nm and localized in the 215-230 nm wavelength region. Precedented structural variation of the phi, psi dihedral angles of the alpha-helix is suggested as a possible explanation. For the important case of alanine-rich peptides, experiments are proposed that may yield temperature corrections for [theta](222) and permit reliable calculations of FH from [theta](222) values.

Objective: To examine the relationship of the frequency of daily doses and medication compliance for hypertensive patients. Design: Retrospective study, nonrandomized control trial. Setting: Rural, general community. Participants: Convenience sample of 55 outpatients who were prescribed antihypertensive therapy exclusively and whose therapy had been consistent for at least 14 months. Data Extraction: Pharmacy records were accessed to determine the medication compliance of these participants. Main Outcome Measure: Medication compliance differences between participants who were on a once-a-day antihypertensive regimen versus a two-or-more × a day regimen. Results: Patients in the once-a-day regimen group were significantly more compliant than those in the two-or-more × a day group. Conclusions: Consideration must be given to simplification of medication regimens to improve compliance. J Pharm Technol 1994;10:115–7.

An unprecedented, high degree of helicity as judged by CD spectroscopy is observed in N-templated model peptides of the type AcHel-(Ala

The immune environment of human soft-tissue injury is unstudied. We studied fracture soft-tissue hematomas (FxSTH) in 56 patients with high-energy bony fractures. FxSTH serum and mononuclear cells (MNC) as well as fracture patient plasma and blood MNC were studied. Twenty healthy controls donated plasma and MNC. Soluble tumor necrosis factor (TNF)-alpha, interleukin (IL-1 beta, IL-2, 6, 8, 10, 12, and interferon-gamma were studied by enzyme linked immunosorbent assay. Cells were studied by flow cytometry after cell-membrane stains for CD-14, TNF-alpha (mTNF), and human leukocyte antigen-DR, or intracellular stains for TNF (icTNF) and IL-10. Thirty-six patients with Injury Severity Score15 were analyzed further to evaluate the effects of isolated fracture on systemic immunity. Cytokines were rarely detectable in control plasma. TNF-alpha, IL-1 beta, IL-2, and interferon-gamma were rarely found in FxSTH serum or fracture patient plasma. All FxSTH sera were rich in IL-6, peaking before 48 hours (12,538 +/- 4,153 vs. 3,494 +/- 909 pg/mL, p = 0.02, U test). In Injury Severity Score15, IL-6 was not detectable in most early fracture patient plasma, but rose after 48 hours (p = 0.028). FxSTH serum IL-8 peaked after 48 hours (440 +/- 289 vs. 4,542 +/- 1,219 pg/mL, p = 0.006) and circulating IL-8 appeared after 72 hours. IL-6 and IL-8 showed gradients from FxSTH serum to paired PtS (p0.05, Wilcoxon). IL-10 was abundant (884 +/- 229 pg/mL) in FxSTH serum24 hours old. FxSTH serum IL-12 peaked late (3,323 +/- 799 pg/mL, day 4-7) then fell (p0.001, analysis of variance). Only IL-12 was higher in fracture patient plasma (1,279 +/- 602 pg/mL) than FxSTH serum (591 +/- 327 pg/mL) during the first 48 hours (p = 0.032, U test). On flow cytometry, control monocytes expressed 201 +/- 31 mTNF sites/cell, but icTNF was absent. mTNF was up-regulated after injury more in FxSTH monocytes (3,202 +/- 870 sites/cell) than peripheral blood monocytes (584 +/- 186 sites/cell) (p0.05 vs. peripheral blood monocytes by Wilcoxon, p0.001 vs. control monocytes by U test). Intracellular IL-10 was abundant in all MNC, but varied widely after injury. Fracture and peripheral blood monocytes expressed far less human leukocyte antigen-DR than control monocytes. Fractures create an inflammatory local environment. Proximal mediators are cell-associated and relatively confined to the wound, but soluble IL-6, IL-8, and IL-10 are abundant and probably exported. Systemic MNC have complex responses to local injuries. These may reflect the combined impact of multiple soluble cytokines initially generated within the wound. FxSTH appear to be a potentially important source of immunomodulatory cytokines in trauma.

Persons who work with human cadavers on dissection tables during and after embalming may be exposed to a variety of toxic vapors. The effectiveness of controlling such exposures by attaching an exhaust duct to the space below the work surface of a dissection table was investigated. Breathing zone concentrations of volatile materials emanating near the table surface were measured at four exhaust flow rates and two different levels of enclosure of the source. Test results showed mean reductions of 83–93 percent with exhaust flow rates from 1.4–4.2 m3/min (50–150 cfm) compared with no local exhaust ventilation, and a reduction of 100 percent at 7.1 m3/min (250 cfm). However, increased enclosure of the source, achieved by lowering the source into the table, did not appreciably affect breathing zone exposures. Since real work settings may differ from experimental conditions, verification of control efficacy by exposure monitoring is essential. Nevertheless, this simple table modification appears to be...

There have been numerous papers over the past ten years dealing with x-ray protection in the range from 500 to 2,000 kv. (1). The data from these papers vary somewhat because the conditions of the experiments were not always the same and could not readily be correlated. Part of this variance has been attributed to differences in the high-voltage wave form and inherent filtration for the various experimental arrangements. Preliminary data (1) have indicated that the size of the irradiated area of the barrier may also be an important variable. The magnitude and limits for this variable have not, however, been explored quantitatively. The present report will deal with x-ray beams of various sizes produced by direct current potentials of 500, 600, 800, 1,000, and 1,400 kv. with a transmission target. Barriers of lead and concrete will be considered. Concrete has been generally accepted in the energy range above about 500 kv. where space is not important, because it is structurally self-supporting and relative...

A great deal of work has been done in recent years to determine how the attenuation of an x-ray beam is modified by the contribution of radiation scattered in the absorber. This scattering contribution depends on the irradiated area and on the solid angle subtended by the detector at the absorbers. The limiting case of a small irradiated area and a small detector solid angle is referred to as “good” or “narrow-beam” geometry; “poor” or “broad-beam” geometry implies that the irradiated area or the detector solid angle is large. In protection studies the term “broad beam” is slightly more restrictive, being used when both the irradiated area and the detector solid angle are large enough so that any further increase in either would not affect the attenuation. It has been found that when the Compton effect contributes to the absorption mechanism, the attenuation per unit thickness under broad-beam conditions is less than with a narrow beam. This increase in penetration is due to the fact that the Compton effe...

The determination of the penetration of high-energy X-rays through matter is an essential element in the design of the protective shielding to be placed around high-energy accelerators. The National Committee on Radiation Protection has published recommendations (1) for thicknesses of concrete shields to be used around betatrons and synchrotrons operating at energies up to 100 Mev. These recommendations are based, in large part, on experimental data on X-ray penetration in concrete obtained with a betatron operating at peak energies ranging from 6 to 38 Mev (2). Calculations of the expected attenuation indicated that the shape of the attenuation curve in concrete would not vary significantly if the operating energy of the betatron were to be raised from 39 Mev to 100 Mev, and for this reason the curve measured at 38 Mev was considered applicable at 100 Mev. The work to be described here was designed to extend the measurements to the 100to 200-Mev region in concrete and to provide similar data for lead. Lead, which has a high atomic number and high density compared to concrete, is a logical material for a protective barrier when space is too limited for the required thickness of concrete. Extensive tables of calculated build-up factors in lead are available for photon energies up to 10 Mev (3). Attenuation in lead has been measured out to one decade, i.e., a factor of 10, for betatron energies ranging from 10 Mev to 100 Mev (4), and out to four decades for the radiation from a 330Mev synchrotron (5). The graphs presented below provide attenuation data, over three decades in lead, for synchrotron operating energies of 86 and 176 Mev. In addition, a comparison is made between the measured attenuation curve at 10 Mev and the estimated attenuation curve that would be obtained by combining the calculated build-up factors with the measured spectrum from a 10-Mev betatron.