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Background and Objectives: Family medicine clerkship directors must secure an adequate number of teaching sites while maintaining or improving the quality of teaching. This survey details how family medicine clerkship directors identify community-based clinical sites with performance challenges, types of challenges, and whether a remediation option exists for struggling clinical sites or preceptors. This study also investigates the relationship between clerkship structure and problems with maintaining high-quality teaching sites. Methods: Data were gathered and analyzed as part of the 2018 Council of Academic Family Medicine’s (CAFM) Educational Research Alliance (CERA) survey of family medicine clerkship directors. Results: There was a significant relationship between ease/difficulty of identifying clinical sites and paying preceptors (P=.032). A lower proportion of sites where a system is in place for remediation reported it being difficult to identify clinical sites (70.0% vs 92.2%, respectively, P=.011). Having a remediation system in place was also associated with less removal of sites (2.5% removed three or more sites vs 25% removed three or more sites, respectively, P=.005). Conclusions: Medical education leaders can explore payment to incentivize community-based preceptors in schools where identifying clinical sites is a challenge. Offering centralized preceptor development activities from medical schools, geared toward the importance of evaluations, balancing learners and opportunities for student engagement, may overcome some of the identified challenges. Medical schools may also consider providing additional time and support for clerkship directors to assist with tracking teaching quality at sites, and to assist struggling preceptors prior to removing them from teaching.

The oxidative potential (OP) of atmospheric fine particulate matter (PM(2.5)) has been linked to organic content, which includes polycyclic aromatic hydrocarbons (PAHs). The OP of 135 individual PAHs (including six subclasses) was measured using the dithiolthreitol (DTT) consumption assay. The DTT assay results were used to compute the concentration of each PAH needed to consume 50% of the DTT concentration in the assay (DTT(50)), and the reduction potential of the PAHs (ΔG(rxn)). Computed reduction potential results were found to match literature reduction potential values (r(2) = 0.97), while DTT(50) results had no correlations with the computed ΔG(rxn) values (r(2) < 0.1). The GINI equality index was used to assess the electron distribution across the surface of unreacted and reacted PAHs. GINI values correlated with ΔG(rxn) in UPAH, HPAH, and OHPAH subclasses, as well as with all 135 PAHs in this study but did not correlate with DTT(50), indicating that electron dispersion is linked to thermodynamic reactions and structural differences in PAHs, but not linked to the OP of PAHs. Three ambient PM(2.5) filters extracts were measured in the DTT assay, alongside mixtures of analytical standards prepared to match PAH concentrations in the filter extracts to test if the OP follows an additive model of toxicity. The additive prediction model did not accurately predict the DTT consumption in the assay for any of the prepared standard mixtures or ambient PM(2.5) filter extracts, indicating a much more complex model of toxicity for the OP of PAHs in ambient PM(2.5). This study combined computed molecular properties with toxicologically relevant assay results to probe the OP of anthropogenically driven portions of ambient PM(2.5), and results in a better understanding of the complexity of ambient PM(2.5) OP.

The oxidative potential (OP) of atmospheric fine particulate matter (PM2.5) has been linked to organic content, which includes polycyclic aromatic hydrocarbons (PAHs). The OP of 135 individual PAHs (including six subclasses) was measured using the dithiolthreitol (DTT) consumption assay. The DTT assay results were used to compute the concentration of each PAH needed to consume 50% of the DTT concentration in the assay (DTT50), and the reduction potential of the PAHs (ΔGrxn). Computed reduction potential results were found to match literature reduction potential values (r2 = 0.97), while DTT50 results had no correlations with the computed ΔGrxn values (r2

Malaria is a devastating disease affecting hundreds of millions of people worldwide. Computational chemistry is on the front lines of the development of new and more effective compounds for reducing the transmission of the malaria parasite. The newly developed localization-delocalization matrices and the principal component eigenvectors derived from the localization-delocalization matrices have been shown previously to be good descriptors for relating molecular electronic structure to molecular properties/activities. The principal components of the localization-delocalization matrices were successfully used to build predictive models of the toxicities of semiochemicals to mosquitoes and the electroantennographic responses of mosquitoes to the electronic structures of repellents.

Jeremiah 1:17–19 brings to a conclusion the call narrative of the prophet Jeremiah and contains the residual memory of the words of Yahweh by which the prophet lived across a lifetime of ministry. An analysis of the text reveals a charge/threat and assurance/encouragement framework that helped to embolden and sustain Jeremiah as he lived under a withering calling to speak all of the words of Yahweh against powerful people on all sides. It also probes for elements that empowered Jeremiah to emerge and re-emerge through his personal struggles to go the distance and fulfill his charge. These words also yield insight into how a prophet who lived through much abuse and loneliness could endure and grow more resilient. Jeremiah is presented as a model for those who would live out a calling amid challenges and conflict. The article addresses the strengthening process that enables some to go the distance in ministry at a time when so many are bailing out.

Background: Health information technology (HIT) is utilized by people with different chronic conditions such as diabetes and hypertension. However, there has been no comparison of HIT use between persons without a chronic condition, with one chronic condition, and multiple (≥2) chronic conditions (MCCs). Objective: The aim of the study was to assess the difference in HIT use between persons without a chronic condition, with one chronic condition, and with MCCs, to describe the characteristics of HIT use among those with chronic conditions and to identify the predictors of HIT use of the persons with one chronic condition and MCCs. Methods: A secondary data analysis was conducted in spring 2017 using the National Health Interview Survey (NHIS) 2012 Family Core and Sample Adult Core datasets that yielded 34,525 respondents aged 18 years and older. Measures included overall HIT use (ie, any use of the following five HIT on the Internet: seeking health information, ordering prescription, making appointment, emailing health provider, and using health chat groups), as well as sociodemographic and health-related characteristics. Sociodemographic and health characteristics were compared between HIT users and nonusers among those who reported having at least one chronic condition using chi-square tests. Independent predictors of HIT use were identified using multiple logistic regression analyses for those with one chronic condition, with MCCs, and without a chronic condition. Analyses were weighted and performed at significance level of .005. Results: In 2012, adults with one health chronic condition (raw count 4147/8551, weighted percentage 48.54%) was significantly higher than among those with MCCs (3816/9637, 39.55%) and those with none of chronic condition (7254/16,337, 44.40%, P

© 2017 American Headache Society Background: Given the safety concerns regarding pharmacological agents, and the considerable impact of headache and migraine on the sufferer's quality of life, many people seek other treatment options beyond conventional medication and care to address their symptoms; this includes complementary and alternative medicine (CAM). Some CAM interventions have shown promising results in clinical trials of headache and migraine management. Nonetheless, there has been little research exploring the reasons for using CAM, and the types of CAM used, among this population. Objective: The study aimed to answer the following questions: (1) Which CAM modalities are used most frequently among migraine/headache sufferers? and (2) What are the self-reported reasons for CAM use among migraine/headache sufferers?. Methods: This secondary analysis of data from the 2012 U.S. NHIS (a national cross-sectional survey) examined the use of CAM among migraine/headache sufferers, including the main reasons related to CAM use. Data were weighted and analyzed using STATA 14.0. Results: The sample of 34,525 adults included 6558 (18.7%) headache/migraine sufferers. Of the headache/migraine sufferers, a substantial proportion (37.6%, n = 2427) used CAM for various conditions; however, CAM use specifically for headache/migraine was much less prevalent (3.3%, n = 216). Of those who used CAM for headache/migraine, about half used CAM in conjunction with prescription (47.8%, n = 100) or over-the-counter medication (55.1%, n = 113). As severity of headache/migraine increased so did the likelihood of using CAM (severe migraine odds ratio [OR] = 2.32; 95% confidence interval [CI]: 1.41, 3.82; both recurring headache/severe migraine OR = 3.36; 95% CI: 2.08, 5.43; when compared to those with recurring headache only). The most frequently used CAM modality among all headache/migraine sufferers (N = 6558) was manipulative therapy (22.0%, n = 1317), herbal supplementation (21.7%, n = 1389) and mind-body therapy (17.9%, n = 1100). The top 3 reasons for using CAM for headache were general wellness (28.7%, n = 60/209), improving overall health (26.8%, n = 56/209), and reducing stress (16.7%, n = 35/209). Conclusions: Although CAM is used by many sufferers of headache/migraine, the use of CAM specifically for the treatment of headache/migraine is relatively low in the United States. The study also assesses the key differences of CAM use among headache/migraine sufferers in NHIS 2012 compared with those in NHIS 2007, and identifies shortfalls in the evidence-base of several CAM modalities used by U.S. adults for headache/migraine. This information may assist health providers and consumers in making informed decisions about the safest and most appropriate approach to managing headache/migraine.

Anchor bolts in annular stand-off base plates connecting cantilever sign and signal structures to concrete foundations may experience high shear from base plate torsion and direct shear forces. A three-phase experimental study evaluated the steel shear strength of anchor bolts in grouted and ungrouted annular stand-off base plate connections to concrete. Phase 1 included flush-mounted and ungrouted stand-off base plates with 5/8- and 1-in.-diameter bolts loaded in direct shear. Phase 2 employed a novel torsion test approach on 10 circular groups of six 5/8-in.-diameter bolts installed in flush-mounted, ungrouted stand-off, and grouted stand-off base plates, along with three ungrouted groups of three 1-in.-diameter bolts. Phase 3 comprised one ungrouted and three grouted full-scale annular base plate tests of six 1.25-in.-diameter bolts under predominantly torsion loading. Results from this study suggest that AASHTO's provisions allowing bolt bending stresses to be ignored for anchor bolts with an exposed ...

Background: Photosystem II is an essential component of oxygenic photosynthesis. Results: Photosystem II is specifically decreased in rubredoxin mutants of the green alga Chlamydomonas reinhardtii, the cyanobacterium Synechocystis sp. PCC 6803, and the plant Arabidopsis thaliana. Conclusion: Rubredoxin is required for photosystem II, and not photosystem I, accumulation in these organisms. Significance: Rubredoxin was likely important in the evolution of oxygenic photosynthesis., In oxygenic photosynthesis, two photosystems work in tandem to harvest light energy and generate NADPH and ATP. Photosystem II (PSII), the protein-pigment complex that uses light energy to catalyze the splitting of water, is assembled from its component parts in a tightly regulated process that requires a number of assembly factors. The 2pac mutant of the unicellular green alga Chlamydomonas reinhardtii was isolated and found to have no detectable PSII activity, whereas other components of the photosynthetic electron transport chain, including photosystem I, were still functional. PSII activity was fully restored by complementation with the RBD1 gene, which encodes a small iron-sulfur protein known as a rubredoxin. Phylogenetic evidence supports the hypothesis that this rubredoxin and its orthologs are unique to oxygenic phototrophs and distinct from rubredoxins in Archaea and bacteria (excluding cyanobacteria). Knockouts of the rubredoxin orthologs in the cyanobacterium Synechocystis sp. PCC 6803 and the plant Arabidopsis thaliana were also found to be specifically affected in PSII accumulation. Taken together, our data suggest that this rubredoxin is necessary for normal PSII activity in a diverse set of organisms that perform oxygenic photosynthesis.

Objective To compare patients' complementary and alternative medicine (CAM) use and physicians' familiarity with certain CAM modalities in the same setting and to assess patient–provider dialogue about patients' CAM use. Methods An observational survey study with convenience sampling at ambulatory family medicine clinics in two Texas cities. A total of 69 healthcare providers and 468 patients completed the surveys. Patients' surveys assessed use of 27 CAM therapies, perception of CAM use and interaction with providers. Providers' survey assessed perception and attitude toward CAM use. Results CAM modalities most used by the patients are not those modalities that providers best understood. Of the 330 patients (70%) who responded to the relevant questions about discussing CAM, 44.5% reported never having discussed CAM use with their providers. Binomial logistic regression revealed no link between age, gender or ethnicity for discussing CAM with providers. College-educated patients (adjust OR=2.8, 95%CI=1.3–6.0) and US citizens were both about three times more likely to discuss CAM than their counterparts. Conclusion Lack of knowledge and unfamiliarity with CAM modalities might prevent important patient–provider discussions. Practice implications Providers should use existing resources and encourage a bilateral dialogue that involves transferring of information and assisting patients in decisions making about CAM use and health care.

Entrepreneurial researchers utilize databases on new and emerging businesses that provide the contact data and other demographic information for research samples. Based on a literature review, the integrity of this data is often assumed, and the vendor's claims as to its accuracy are relied upon. This article tests the accuracy and reliability of one such database, the U.S. New Business database from ReferenceUSA. Specifically, these businesses were contacted to test the validity of the information provided. The research findings suggest that the U.S. New Business database from ReferenceUSA is not a vetted database, and researchers cannot rely on the vendor's promise of accuracy.

The purpose of this article is to describe collaboration between entrepreneurship faculty and business librarians to improve the quality of market research conducted by the students in an Introduction to Entrepreneurship course. This article describes: the course objectives; the stumbling blocks experienced by students, faculty, and librarians; the business/library partnership solution; and the benefits for all stakeholders that have emerged from this partnership.

This research evaluated the interaction between the shear modulus of steel-reinforced neoprene bearing pads and the shear strain rate. The following interactions related to variations in the shear modulus were investigated for pads with various shape factors: product approval strain rates versus short-term field strain rates, short-term field strain rates versus long-term field strain rates, reduction in shear modulus due to load cycles, and compressive stress. Forty-two tests were performed with test equipment designed to apply a shear strain at a variety of rates (50% shear strain at rates from 45 s to 90 days) while applying a sustained compressive load. Test results indicated that the shear modulus was reduced on average by 7% when tests were performed with the short-term field strain rates of 50% over 12 h instead of the product approval strain rates of 50% over 30 to 60 s, that there was essentially no reduction in shear modulus with long-term field loading rates of 50% over durations up to 90 days versus short-term field strain rates, that the shear moduli for pads that had never been load-cycled were approximately 12% higher than those of cycled pads, and that the effect of compressive stress agrees with previous work (i.e., the shear modulus decreases with increased compression particularly for bearings with low shape factors).

A protected decapeptide corresponding to a section found in the last half of the protein chain of rubredoxin has been prepared by standard peptide methods.

A synthesis is described for the protected N-terminal nonapeptide (A11-A 19) fragment of rubredoxin, methyl Na-benzyloxycarbonyl-O-t-butyl-L-tyrosyl-L-isoleucyl-O-t-butyl-L-tyrosyl-L-t-butyl-L-aspartyl-L-prolyl-L-alanyl-L-leucyl-L-valyl-glycinate.

Active learning has attracted considerable attention in higher education in response to concerns about how and what students are learning. There are many different forms of active learning, yet most of them are classroom based. We propose an alternative to active learning in the classroom through active learning outside of the classroom in the form of student consulting projects. While the literature on student consulting has largely focused on projects to assist small business owners, this research demonstrates the potential for using student-consulting projects in the Production/Operations Management course. We use a case study to describe the use of a student-consulting project as an alternative to the other types of active learning described in the Operations Management education literature.

The sintering kinetics of a pure magnesium aluminate spinel, MgAl2O4, and that doped with LiF were determined through the use of the master sintering curve technique developed by Su and Johnson.20 Powders with 0%, 0.5%, and 1.0% by mass LiF were densified in a vacuum hot press under a range of unaxial pressures. After the sintering mechanisms in each temperature and pressure regime were determined, an optimized vacuum hot-pressing schedule was formulated for spinel powders doped with 1.0% by mass of LiF. In addition to forming a transient liquid phase, the presence of LiF leads to the formation of oxygen vacancies that promote late-stage sintering in MgAl2O4.

The epidemiology of deliberate self-poisoning presentations to the emergency department (ED) of Ninewells Hospital was reviewed over a six-month period. The results were related to previously published Scottish data. During the six month period, 530 patients presented (2.1% of total). There was a female preponderance with over 65% of patients aged less than 40 years. Patients lived more commonly in areas of higher deprivation. The drugs most commonly involved were paracetamol (39.25%) and antidepressants (35.1%). Of the presentatons 80.2% required no treatment apart from basic observations. Only 1.51% received activated charcoal and no gastric lavages were performed. Of the presentations, 75.6% were discharged after observation in the ED, 8.9% were admitted to a psychiatric hospital and 5.5% were admitted to general medicine department. Deliberate self-poisoning continues to be a major cause of hospital admissions in Scotland. In Tayside, it is predominantly a problem of the young and socially deprived. Consistent with recent national trends, paracetamol was the most common drug relating to overdose. The use of an ED observation ward is supported as a vast majority of patients are admitted for less than 24 hours and require no active treatment.

Active learning has attracted considerable attention in higher education in response to concerns about how and what students are learning. Many pedagogies may be categorized as active learning, although most are classroom-based. The authors propose an alternative to ‘active learning in the classroom’, which they characterize as ‘active learning outside of the classroom’, and present in the form of field-based student consulting projects. Field-based consulting forces students to engage in active learning. By participating in consulting teams, they are moved into a new realm of learning. In undertaking consultancy, rather than receiving information in a somewhat passive manner, students evaluate a real-world business problem and must themselves decide on a solution. For the student, the benefits of consulting include gaining experience in dealing with business owners and offering a professional opinion on a real business problem. The authors propose a framework for this design, describe how other instructors could arrange for their students to conduct consulting projects, and then identify possible directions for future research.

This paper presents an overview of a behavioral model to predict the failure load of anchorage systems with adhesive bonded anchors loaded in tension. The development and complete behavioral model was presented by Eligehausen, Cook, and Appl in the November-December 2006 edition of the American Concrete Institute Structural Journal.

Reactions between LiF and MgAl 2 O 4 at temperatures up to 1500°C are examined with a variety of tools, including differential scanning calorimetry, thermo-gravimetric analysis, X-ray diffraction, and scanning electron microscopy. LiAlO 2 and MgF 2 are found to be the active reaction products at these temperatures. A transient liquid phase comprising MgF 2 and LiF forms at intermediate temperatures, but then is consumed at higher temperatures during the reformation of MgAl 2 O 4 . If processed as an uncompacted powder mixture, all of the initial LiF in the system eventually vaporizes at temperatures exceeding 1300°C. A new reaction sequence relevant to the densification of LiF-doped MgAl 2 O 4 spinel is proposed.

PurposeThe purpose of this paper is to improve assessment and feedback processes in the training practices of very small firms, thereby improving the firms' human capital.Design/methodology/approachThe paper reviews research and practice on effective assessment and feedback.FindingsBased on this paper, human resources are increasingly seen as a potential source of sustained competitive advantage, and well‐trained workers can boost the performance of even very small firms. Hence, a method is provided which very small firms can use to create and implement a structured assessment tool that builds on observation of critical incidents to illustrate the differences between poor, average, and good performance.Practical implicationsThe paper shows that readers can use the provided tools to assess and improve employee performance, thereby enhancing their firm's competitive position.Originality/valueThis paper can be used by very small firms to evaluate employee performance and provide employees with both positive and constructive feedback. Additionally, suggestions are provided that allow these firms to use this feedback to effectively set employee performance goals and action plans.

Recent changes in medical training prompted by Modernising Medical Careers and the New Deal requires a more structured, competency based training programme. This paper describes the development of such a programme in an emergency medicine department of a teaching hospital. It describes the process of design and the various aspects incorporated to develop a balanced system of training, appraisal, and assessment.

Bridges that span navigable waterways must be designed to resist potential impact loads associated with barge or ship collisions. Despite this fact, few experimental data have been collected about the magnitude and nature of such loads. Vessel-impact components of bridge design specifications, such as the AASHTO bridge design provisions, are therefore based on limited experimental data. Recently, a bridge in the United States (Florida) was replaced with a new structure and thus afforded a unique opportunity to conduct full-scale barge impact tests on piers of the preexisting structure before it was demolished. Tests were conducted on two piers with fundamentally different types of foundation systems. Tests on one pier also were repeated in two structural configurations (with the superstructure present and then with it removed). In each test, instrumentation and high-speed data acquisition systems were used to quantify the dynamic loads generated during controlled collision events. Experimental procedures used during the tests are described, and selected test results are presented, including experimentally measured dynamic impact loads and associated barge deformations. Comparisons are then presented between experimentally collected data and the current AASHTO barge impact bridge design provisions.

This article compares the educational background and years of work experience of students entering a Microenterprise Training Institute (MTI) program. Hypotheses were developed and tested to determine whether human capital attributes (education and work experience) influenced students' ability to graduate from an MTI program, to submit homework on time, and/or contributed to a better score on an evaluation of their business plan. Results indicated that education level was a significant, positive influence on the ability to graduate and on business plan scores, but had no influence on on‐time homework completion. Work experience had no effect on ability to graduate, homework submission, or business plan score.

Value creation has long been hailed as the major objective of business firms by many management researchers. Some authors state that a firm must create value for its shareholders; some insist that value must be created not just for shareholders but also for all stakeholders. However, most discussions of value creation do not address an important question: "For whom the value is created?" The purpose of this paper is to take a first step to fill this void and propose a model of value creation along three dimensions: financial, nonfinancial, and time. It is hoped that the model will contribute to a better understanding of how strategic and operational decisions of managers may create value for some stakeholders while destroying it for others.

A series of 12 pretensioned beams were loaded to failure in the laboratory under a concentrated load, placed to produce a shear span with a length-to-depth ratio of 1.5, so as to fail the beam in shear. In an attempt to reduce the prestress transfer length for the strands and increase the shear strength of the beam near the support, anchorage devices were attached to the ends of the prestressing strands before casting. For most beams, these devices were totally encased in concrete during the casting process. These modified beams exhibited no significant increase in shear strength relative to otherwise identical reference beams fabricated without the devices. A final set of beams was fabricated with the anchorage devices bearing externally on the ends of the beams, and with a deliberate debonding between the strand and concrete near the ends of the beams. These girders exhibited higher failure loads and enhanced ductility, developing a very distinct strut-and-tie mechanism at failure. The study indicated the potential of strand end anchorage to enhance shear capacity in the end regions of pretensioned girders.

Fluorogenic probes dual-labeled with reporter and quencher dyes use a change in fluorescence to monitor biochemical events (e.g., substrate binding or enzyme digestion). Such events change the reporter-quencher distance, which affects fluorescence. Recently, it is has been shown that static quenching through intramolecular dimers is an important mechanism that can sometimes be more efficient than Förster resonance energy transfer (FRET).

Several fluorescence resonance energy transfer (FRET) oligonucleotide probes were made with different internal linkages between the DNA and the quencher dye. In one example, a 5'-fluorescein beta-actin-based 26-mer DNA sequence was synthesized bearing an internal Tamra quencher. Two different versions were prepared using either conventional C5 [N-(6-aminohexyl)-3-acrylamido]pyrimidine-modified uridine and solution-phase Tamra active ester coupling or solid-phase addition of a Tamra amidite to a C5 [N-(6-hydroxyhexyl)-3-acrylamido]pyrimidine-modified uridine. The products were compared in functional assays. They performed very similarly both in a fluorescence-based melting point assay as well as in quantitative PCR. Another set of beta-actin probes were synthesized utilizing N4 [N-2-(ethylene glycol ethyl)-5-methyl]cytidine and solid-phase Tamra amidite addition at positions flanking those of the uridine. These versions gave lower T(m)s than either uridine-labeled probe and did not work as well in quantitative PCR. A control experiment using oligonucleotides with the same modified residues but without fluorophores attached revealed the same trend as the T(m) study of internal Tamra-labeled probes. Experimental details for the synthesis, purification, and testing are presented.

Fatigue failure of cantilever (mast arm) supports for traffic signs and signals due to wind-induced vibrations has occurred in several states. A preferred method of reducing and perhaps eliminating these failures is to decrease the number and magnitude of load cycles by installing a damping device. Several types of damping devices were developed and tested on a mast arm at the University of Florida Structures Laboratory and field mast arm structures in Gainesville and Tampa, Florida. Both free-vibration and forced-vibration techniques were used to evaluate the responses of the structures. In addition, response under actual wind conditions was determined for the preferred damping device on the Tampa installation. Damping devices tested included tuned mass dampers, liquid dampers, friction dampers, damping devices installed at the arm-pole connection, and impact dampers. The preferred device was a tapered impact damper that functions in both the horizontal and vertical directions. This device was selected b...

T-phase propagation from ocean onto land is investigated by comparing data from hydrophones in the water column with data from the same events recorded on island and coastal seismometers. Several events located on Hawaii and the emerging seamount Loihi generated very large amplitude T phases that were recorded at both the preliminary IMS hydrophone station at Point Sur and land-based stations along the northern California coast. We use data from seismic stations operated by U. C. Berkeley along the coast of California, and from the PG&E coastal California seismic network, to estimate the T-phase transfer functions. The transfer function and predicted signal from the Loihi events are modeled with a composite technique, using normal mode-based numerical propagation codes to calculate the hydroacoustic pressure field and an elastic finite difference code to calculate the seismic propagation to land-based stations. The modal code is used to calculate the acoustic pressure and particle velocity fields in the ocean off the California coast, which is used as input to the finite difference code TRES to model propagation onto land. We find both empirically and in the calculations that T phases observed near the conversion point consist primarily of surface waves, although the T phases propagate as P waves after the surface waves attenuate. Surface wave conversion occurs farther offshore and over a longer region than body wave conversion, which has the effect that surface waves may arrive at coastal stations before body waves. We also look at the nature of T phases after conversion from ocean to land by examining far inland T phases. We find that T phases propagate primarily as P waves once they are well inland from the coast, and can be observed in some cases hundreds of kilometers inland. T-phase conversion attenuates higher frequencies, however we find that high frequency energy from underwater explosion sources can still be observed at T-phase stations.

This article provides details of research work which aims to increase the range of applications in which membranes can be used by improving the epoxies used to form tube-sheets, making them more chemically and thermally stable, more resistant to organic solvents, and with improved mechanical properties.

5-Carboxy Tamra 1 was conjugated to 4-hydroxypiperidine with BOP and N-methylmorpholine, and the resulting 5-(N-pipyridyl-4-hydroxy)-Tamra carboxamide 2 was treated with 2-cyanoethyl tetraisopropylphosphorodiamidite to give 5-[N-pipyridyl-4-O-(2-cyanoethyl diisopropylphosphoramidite)]-Tamra carboxamide 3. Solutions of 3 were coupled onto the 5'-hydroxyl of solid-phase-supported DNA fragments with standard amidite coupling techniques. Cleavage and deprotection with aqueous tert-butylamine cocktail gave 5-Tamra-functionalized DNA as well as an additional compound without the Tamra chromophore. A mass spectrum of this product showed the incorporation of tert-butylamine. The extra product was completely suppressed by including a 5 min acetylation step after coupling. A model study of 3 coupled onto thymidine-functionalized CPG showed similar results. NMR and mass spectra of cleaved products confirmed the addition of tert-butylamine to the minor product. Coupling a Tamra active ester onto T CPG which was previously coupled with N-(4-methoxytrityl)piperidyl-4-O-(2-cyanoethyl diisopropylphosphoramidite) 4 produced the same major Tamra-bearing product, which coeluted on reverse phase HPLC with the major product generated with 3.

Literature syntheses of 4,7,2‘,7‘-tetrachloro-5(and 6)-carboxy-fluorescein (“5 and 6 TET”) 1 and 4‘,5‘-dichloro-2‘,7‘-dimethoxy-5(and 6)-carboxyfluorescein (“5 and 6 JOE”) 2 are reviewed, and new, preparatively useful methods are presented. A three-step synthesis of 1 was developed, which proved to be more efficient than the published seven step synthesis of this compound. The published synthesis of 2 also proved difficult to reproduce, and a better workup of the key intermediate 2-chloro-4-methoxy resorcinol was devised. Isolation of purified single isomers of both dyes is described.

This study compared the public policy interactions over time between small and medium-sized firms. Hypotheses related to firm size, frequency of activity, and influence methods were developed and tested. Small and medium-sized firms had different patterns of public policy involvement, with medium-sized firms reporting less activity but more success in influencing the public policy process than did small firms. Of the influence methods, only letter writing was significant to reported success rates. A regression analysis revealed that firm size and letterwriting variables provided the best fit in a linear-relationship model.

A uridine-based linker immobilized onto polystyrene beads at the 5′ terminus via a phosphodiester group and then used as a universal DNA synthesis support gives post synthesis DNA cleavage in 8 hrs or less without alkali metal salts. DNA produced with the new support was analyzed by HPLC, MALDI mass spectroscopy and PAGE. Each analysis showed DNA of equivalent quality to that produced with standard CPG supports, without contaminating materials resulting from linker or support backbone decomposition.

Mild, efficient conditions have been developed for the preparation of 4-methylbenzhydrylamine polystyrene (MBHA) and aminomethyl polystyrene (AMPS) resins by a two-step procedure with synthons 1a and 1c. The products possess excellent swelling characteristics and acylate readily with linkers yielding useful derivatives, which retain good swelling and reactivity. Comparative studies with these resins, and their poly(ethylene glycol) (PEG) derivatives, yield insights into the role of spacer arm and environment effects in synthesis facilitation.

Dieser Beitrag beschreibt die Grundlagen fur ein allgemeingultiges Konzept zur Bemessung von chemischen Befestigungen. Zuerst werden die ublichen Systeme sowie deren Trag- und Versagensverhalten aufgezeigt. Dabei wird Umgebungseinflussen wie Temperatur, Feuchtigkeit und Reinigung besondere Aufmerksamkeit geschenkt. Dann werden Bemessungskonzepte aus der Literatur vorgestellt. Diese werden anhand einer Datenbank mit den Ergebnissen von etwa 900 Versuchen bewertet. Weiterhin werden daraus eine Grundbeziehung fur ein neues, allgemeines Bemessungskonzept hergeleitet und Bemessungshinweise fur zug-, quer- und schragbelastete Befestigungen gegeben.

Mono- and dialkylferrocenes are readily prepared by the nucleophilic substitution of n -alkyl halides with lithioferrocenes. The products can be purified by short-path distillation or recrystallization. Three alkylferrocenes were prepared by this synthetic strategy and characterized by cyclic voltammetry in aqueous solution.

Large trucks, particularly those with over-cab air deflectors, produce dynamic wind pressures on overhead structures. Oscillations of overhead variable-message sign structures have been observed as a result of these truck-induced wind pressures. The purpose of this research was to determine the magnitude, direction, and frequency of these pressure distributions. The choice of instrumentation used, the design of the apparatus, and the data obtained are discussed. A multiprobe device consisting of Pitot tubes and variable-reluctance pressure transducers was combined with a data acquisition system. Field readings were taken by mounting the apparatus on a bridge overpass and collecting data as trucks passed beneath the bridge. It was found that the wind pressures produced by the trucks were not as large as anticipated, but the frequency of the wind was close to the natural frequency of a typical variable-message sign structure. This creates a resonance condition believed to be a major cause of the oscillations. One possible solution is to increase the stiffness of the structure.

This paper presents the results of an experimental program performed to determine the bond performance of epoxy-coated strands subjected to elevated temperatures. Two test series were conducted to establish the maximum temperature at which epoxy-coated strands retain adequate bond capacity. In the first test series, the specimens were water cured and the strands detensioned at ambient temperature. In the second test series, the specimens were steam cured and the strands detensioned at 150 deg F (66 deg C) for two specimens and 155 deg F (68 deg C) for a third specimen. For both test series, the temperature after detensioning was increased to about 200 deg F (93 deg C). The results of this study indicate that detensioning of epoxy-coated strands should not occur at internal temperatures over 160 deg F (71 deg C).