Order-disorder phenomena have been examined by means of Mossbauer spectroscopy in a variety of ma... more Order-disorder phenomena have been examined by means of Mossbauer spectroscopy in a variety of materials, including (a) tektites and other silicate glasses, (b) magnetic materials such as natural and synthetic magnetoplumbite, M-type hexagonal ferrites and magnetite, and (c) nanocrystalline zinc ferrite. A methodology has been established for the analysis of the local crystal/chemical structures of iron in tektites and its application has reconfirmed a low ferric/ferrous ratio of approximately 0.10 for tektites. Additionally, a greater degree of submirocscopic heterogeneity has been established for Muong Nong tektites in comparison with splash form tektites. The dynamics of the 2b site in hexagonal ferrites has been studied above and below the Curie temperature for magnetoplumbite and its synthetic analogs, and also for polycrystalline and oriented single-crystals of MeFesb{12}Osb{19} (Me=Ba, Sr, Pb). Cation ordering on this site is shown to be dependent on the thermal history of the material, while the dynamic disorder of the 2b site for the end-member hexagonal ferrites is shown to be influenced by the divalent heavy metal species, Me. The influence of chemical composition on the morphology of magnetite has been shown to depend on the site preference of impurity cations: Substitutional impurities with tetrahedral site preferences are postulated to result in the seldom-observed cubic habit. Based on the cation distributions of bulk and nanocrystalline material it is held that the enhanced magnetic moments and susceptibilities of nanocrystalline zinc ferrite are shown to be consistent with surface phenomena, independent of synthesis methodology, and contrary to claims of special effects resulting from a particular synthesis methodology.
Background Emergency department (ED) patients are at increased risk chlamydia (CT) and gonorrhea ... more Background Emergency department (ED) patients are at increased risk chlamydia (CT) and gonorrhea (GC) infection. Though CT/GC prevalence frequently exceeds 8%/4%, clinical symptoms are ambiguous. EDs may be important screening sites if cost-effective screening algorithms can be identified. Objective To determine if ED patient survey responses predict CT/GC infection. Methods Participating ED patients aged 15-34 completed a sexual history survey and provided urine samples (GEN) and oralpharyngeal swabs (ORAL) for CT/GC testing. Surveys were analyzed for associations between specific answers and infection status. Results (preliminary; will end at 300 each females/males) Of 395 participants, mean age was 25.1 years, 65.6% were female, 192 aged 15-24 (younger) and 203 aged 25-34 (older). 31 (7.8%) individuals were infected, including 11 males (8.1%)/20 females (7.7%), with those younger more likely infected (OR=3.317; CI=1.446-7.611). For males, oral infection was associated with giving...
Background Clinicians frequently rely upon patient-provided information to determine an individua... more Background Clinicians frequently rely upon patient-provided information to determine an individual's risk of sexually transmitted disease and screening eligibility. However, general questions may be inadequate to elicit accurate risk estimation information. Objective To determine consistency of patient sexual history survey responses. Methods Emergency department patients aged 15-34 completed a history of sexual activity in the past year; subsequently analyzed for consistency between general and specific sexual activity questions. Results (preliminary; will end at 300 each females/males; correlations will be calculated then) Of 395 participants, mean age was 25.1 years, 65.6% were female, and 90.4% reported being sexually active (Sex12). Of 20 males reporting no Sex12, 5% reported providing male oral sex (mOS), 25% provided female OS (fOS), and 20% received fOS. Of 18 females reporting no Sex12, 11.1% reported providing mOS and 11.1% receiving mOS. Of all 117 males reporting no ...
Endotracheal intubation (ETI) is an essential skill that emergency medicine residents learn throu... more Endotracheal intubation (ETI) is an essential skill that emergency medicine residents learn throughout their training. To evaluate the effect of implementing a postgraduate year (PGY)-1 anesthesiology rotation on ETI success in the emergency department during PGY-2. Residents in the study group completed a 4-week PGY-1 anesthesiology rotation. During the first 6 months of PGY-2, we compared ETI performance of the study group with a control group who did not experience a PGY-1 anesthesiology rotation. Data recorded included date, level of training, first- and second-attempt success, rescue devices used, major adverse events, and intubation scenario. A Pearson χ(2) test was used to compare first-attempt success, overall success (≤2 attempts), and adverse events rates between the 2 groups. Overall success rate for the study groups was 95.7% (111 of 116), compared with 94.5% (137 of 145) for the controls (P = 66). First-attempt success for the study group was 78.4% (91 of 116), compar...
Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) are the most commonly reported diseases... more Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) are the most commonly reported diseases in the USA, with increasing concern regarding cephalosporin-resistant GC strains and growing discussion of routine male screening and analysing extragenital sites. Hospital emergency departments (EDs) may be appropriate screening venues, and our objective was to identify the extent of genital and oropharyngeal CT/GC infection in ED patients. From June 2012 to March 2013, ED patients aged 15-34 were asked to provide a urine sample and oropharyngeal swab for CT/GC analysis and complete a sexual history survey. The 301 female and 192 male participants had a mean age of 25.2 years (SD 4.9); were 65.5% white patients and 33.5% black patients and >85% reported sexual activity in the past year. Tested patient prevalence was 7.7% (any infection/any site; n=38) with no gender differences. Regarding oral infections (n=10), those so infected were more likely to report a friend with a sexually t...
The (anti-) chiral Killing vectors of the supersymmetric Kähler manifold associated with the nonl... more The (anti-) chiral Killing vectors of the supersymmetric Kähler manifold associated with the nonlinear realization of a global symmetry are used to define (anti-) chiral normal coordinates. This in turn leads to a background superfield expansion of the super-Kähler potential that is manifestly gauge invariant and supersymmetric. The chiral normal coordinates are further employed to construct a background superfield expansion
This monitoring program was initiated to assess the population exposure to ambient levels of benz... more This monitoring program was initiated to assess the population exposure to ambient levels of benzene in conjunction with the announcement of benzene as a hazardous material. The program was conducted during the summer and fall of 1977. Average benzene concentrations of 5, 18, and 19 microgram/cu in, respectively, were measured in the widely separated cities of Dallas, Chicago, and Los Angeles. The precision of these data is estimated to be + or - 26 percent of the measured values. The improvement of benzine monitoring and analysis technology was an important secondary objective of this program. However, further research is needed to identify a more favorable collection medium than the Tenex that was used in this study.
Anti-symmetric tensor gauge theories are quantized via the Faddeev-Popov procedure leading to a B... more Anti-symmetric tensor gauge theories are quantized via the Faddeev-Popov procedure leading to a BRS invariant theory without the need for second order ghosts. The quantum mechanical equivalence of these theories to non-linear sigma models is established using the spontaneously broken global symmetry currents. Upon gauging these symmetries the I-Iiggs mechanism is displayed, while for anomalous symmetries an analog of the Wess-Zumino action is constructed in terms of the anti-symmetric tensor gauge fields.
Spontaneous chiral symmetry breaking in supersymmetric quantum electrodynamics is studied by exam... more Spontaneous chiral symmetry breaking in supersymmetric quantum electrodynamics is studied by examining the self-consistent Schwinger-Dyson equations. The equations admit only the trivial solution indicating an absence of mass generation. This is consistent with a non-perturbative, non-renormalization theorem. We also address the case of an explicitly softly broken supersymmetry and find non-trivial solutions to the gap equation for sufficiently strong coupling.
The peroxisome proliferutor ciprofibrate was examined for its ability to initiate hepatocarcinoge... more The peroxisome proliferutor ciprofibrate was examined for its ability to initiate hepatocarcinogenesis in rats. Ciprofibrate was fed in the diet at levels of O%, 0.01% and 0.025 % for 2 weeks in order to induce steady-state peroxisome proliferation. Rats were then subjected to partial hepatectomy and then maintained for 6 months on a basal diet or one containing 0.05 % phenobarbital. Ciprofibrate treatment did not increase the number or volume of altered hepatic foci (putative preneoplastic lesions). However, ciprofibrate treatment increased liver weights in a dose-dependent manner in rats which did not receive phenobarbital. It is concluded that ciprofibrateinduced peroxisome proliferation is not sufficient to induce initiation, but that a permanent change is produced which results in an increased liver weight.
676 YOUTH CRISIS CENTERS indicated that fully two-thirds of the young people within social servic... more 676 YOUTH CRISIS CENTERS indicated that fully two-thirds of the young people within social service pro-grams were there under pressure from their family, school, or the police. Many youths perceive social service programs as allied with the values of parents, school ...
Pyrex Ò is an ubiquitous material that has attained widespread use in laboratory glassware and ho... more Pyrex Ò is an ubiquitous material that has attained widespread use in laboratory glassware and household utensils due to its properties, cost effectiveness, and ease of fabrication. Despite its importance, the structure of borosilicate glass such as Pyrex Ò is not fully understood. Here, we report high resolution 29 Si, 27 Al, and 11 B magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopic measurements at 9.4 and 19.5 T, combined with 27 Al and 11 B multiple-quantum MAS (MQ-MAS), and 11 B Rotor Assisted Population Transfer (RAPT), to identify structural features in Pyrex Ò . A distribution of Q 4 silicon and aluminum sites is observed, and there is no evidence of five or six coordinated aluminum. The 27 Al quadrupolar coupling constants for the tetrahedral aluminum varied from 3.5 to 4.5 MHz, while the isotropic chemical shifts varied from 50 to 65 ppm. Boron-11 measurements resolve four distinct distributions in boron environments: two identified as tetrahedral, BO 4 , and two as trigonal, BO 3 . Tetrahedral sites are distinguished by different second coordination spheres, e.g., BO 4 (0 B, 4 Si) and BO 4 (1 B, 3 Si), and the trigonal sites based on the symmetry of the boron environments.
Solid-state 17 O magic-angle spinning nuclear magnetic resonance measurements at 19.5 Tesla were ... more Solid-state 17 O magic-angle spinning nuclear magnetic resonance measurements at 19.5 Tesla were performed on
Order-disorder phenomena have been examined by means of Mossbauer spectroscopy in a variety of ma... more Order-disorder phenomena have been examined by means of Mossbauer spectroscopy in a variety of materials, including (a) tektites and other silicate glasses, (b) magnetic materials such as natural and synthetic magnetoplumbite, M-type hexagonal ferrites and magnetite, and (c) nanocrystalline zinc ferrite. A methodology has been established for the analysis of the local crystal/chemical structures of iron in tektites and its application has reconfirmed a low ferric/ferrous ratio of approximately 0.10 for tektites. Additionally, a greater degree of submirocscopic heterogeneity has been established for Muong Nong tektites in comparison with splash form tektites. The dynamics of the 2b site in hexagonal ferrites has been studied above and below the Curie temperature for magnetoplumbite and its synthetic analogs, and also for polycrystalline and oriented single-crystals of MeFesb{12}Osb{19} (Me=Ba, Sr, Pb). Cation ordering on this site is shown to be dependent on the thermal history of the material, while the dynamic disorder of the 2b site for the end-member hexagonal ferrites is shown to be influenced by the divalent heavy metal species, Me. The influence of chemical composition on the morphology of magnetite has been shown to depend on the site preference of impurity cations: Substitutional impurities with tetrahedral site preferences are postulated to result in the seldom-observed cubic habit. Based on the cation distributions of bulk and nanocrystalline material it is held that the enhanced magnetic moments and susceptibilities of nanocrystalline zinc ferrite are shown to be consistent with surface phenomena, independent of synthesis methodology, and contrary to claims of special effects resulting from a particular synthesis methodology.
Background Emergency department (ED) patients are at increased risk chlamydia (CT) and gonorrhea ... more Background Emergency department (ED) patients are at increased risk chlamydia (CT) and gonorrhea (GC) infection. Though CT/GC prevalence frequently exceeds 8%/4%, clinical symptoms are ambiguous. EDs may be important screening sites if cost-effective screening algorithms can be identified. Objective To determine if ED patient survey responses predict CT/GC infection. Methods Participating ED patients aged 15-34 completed a sexual history survey and provided urine samples (GEN) and oralpharyngeal swabs (ORAL) for CT/GC testing. Surveys were analyzed for associations between specific answers and infection status. Results (preliminary; will end at 300 each females/males) Of 395 participants, mean age was 25.1 years, 65.6% were female, 192 aged 15-24 (younger) and 203 aged 25-34 (older). 31 (7.8%) individuals were infected, including 11 males (8.1%)/20 females (7.7%), with those younger more likely infected (OR=3.317; CI=1.446-7.611). For males, oral infection was associated with giving...
Background Clinicians frequently rely upon patient-provided information to determine an individua... more Background Clinicians frequently rely upon patient-provided information to determine an individual's risk of sexually transmitted disease and screening eligibility. However, general questions may be inadequate to elicit accurate risk estimation information. Objective To determine consistency of patient sexual history survey responses. Methods Emergency department patients aged 15-34 completed a history of sexual activity in the past year; subsequently analyzed for consistency between general and specific sexual activity questions. Results (preliminary; will end at 300 each females/males; correlations will be calculated then) Of 395 participants, mean age was 25.1 years, 65.6% were female, and 90.4% reported being sexually active (Sex12). Of 20 males reporting no Sex12, 5% reported providing male oral sex (mOS), 25% provided female OS (fOS), and 20% received fOS. Of 18 females reporting no Sex12, 11.1% reported providing mOS and 11.1% receiving mOS. Of all 117 males reporting no ...
Endotracheal intubation (ETI) is an essential skill that emergency medicine residents learn throu... more Endotracheal intubation (ETI) is an essential skill that emergency medicine residents learn throughout their training. To evaluate the effect of implementing a postgraduate year (PGY)-1 anesthesiology rotation on ETI success in the emergency department during PGY-2. Residents in the study group completed a 4-week PGY-1 anesthesiology rotation. During the first 6 months of PGY-2, we compared ETI performance of the study group with a control group who did not experience a PGY-1 anesthesiology rotation. Data recorded included date, level of training, first- and second-attempt success, rescue devices used, major adverse events, and intubation scenario. A Pearson χ(2) test was used to compare first-attempt success, overall success (≤2 attempts), and adverse events rates between the 2 groups. Overall success rate for the study groups was 95.7% (111 of 116), compared with 94.5% (137 of 145) for the controls (P = 66). First-attempt success for the study group was 78.4% (91 of 116), compar...
Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) are the most commonly reported diseases... more Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) are the most commonly reported diseases in the USA, with increasing concern regarding cephalosporin-resistant GC strains and growing discussion of routine male screening and analysing extragenital sites. Hospital emergency departments (EDs) may be appropriate screening venues, and our objective was to identify the extent of genital and oropharyngeal CT/GC infection in ED patients. From June 2012 to March 2013, ED patients aged 15-34 were asked to provide a urine sample and oropharyngeal swab for CT/GC analysis and complete a sexual history survey. The 301 female and 192 male participants had a mean age of 25.2 years (SD 4.9); were 65.5% white patients and 33.5% black patients and >85% reported sexual activity in the past year. Tested patient prevalence was 7.7% (any infection/any site; n=38) with no gender differences. Regarding oral infections (n=10), those so infected were more likely to report a friend with a sexually t...
The (anti-) chiral Killing vectors of the supersymmetric Kähler manifold associated with the nonl... more The (anti-) chiral Killing vectors of the supersymmetric Kähler manifold associated with the nonlinear realization of a global symmetry are used to define (anti-) chiral normal coordinates. This in turn leads to a background superfield expansion of the super-Kähler potential that is manifestly gauge invariant and supersymmetric. The chiral normal coordinates are further employed to construct a background superfield expansion
This monitoring program was initiated to assess the population exposure to ambient levels of benz... more This monitoring program was initiated to assess the population exposure to ambient levels of benzene in conjunction with the announcement of benzene as a hazardous material. The program was conducted during the summer and fall of 1977. Average benzene concentrations of 5, 18, and 19 microgram/cu in, respectively, were measured in the widely separated cities of Dallas, Chicago, and Los Angeles. The precision of these data is estimated to be + or - 26 percent of the measured values. The improvement of benzine monitoring and analysis technology was an important secondary objective of this program. However, further research is needed to identify a more favorable collection medium than the Tenex that was used in this study.
Anti-symmetric tensor gauge theories are quantized via the Faddeev-Popov procedure leading to a B... more Anti-symmetric tensor gauge theories are quantized via the Faddeev-Popov procedure leading to a BRS invariant theory without the need for second order ghosts. The quantum mechanical equivalence of these theories to non-linear sigma models is established using the spontaneously broken global symmetry currents. Upon gauging these symmetries the I-Iiggs mechanism is displayed, while for anomalous symmetries an analog of the Wess-Zumino action is constructed in terms of the anti-symmetric tensor gauge fields.
Spontaneous chiral symmetry breaking in supersymmetric quantum electrodynamics is studied by exam... more Spontaneous chiral symmetry breaking in supersymmetric quantum electrodynamics is studied by examining the self-consistent Schwinger-Dyson equations. The equations admit only the trivial solution indicating an absence of mass generation. This is consistent with a non-perturbative, non-renormalization theorem. We also address the case of an explicitly softly broken supersymmetry and find non-trivial solutions to the gap equation for sufficiently strong coupling.
The peroxisome proliferutor ciprofibrate was examined for its ability to initiate hepatocarcinoge... more The peroxisome proliferutor ciprofibrate was examined for its ability to initiate hepatocarcinogenesis in rats. Ciprofibrate was fed in the diet at levels of O%, 0.01% and 0.025 % for 2 weeks in order to induce steady-state peroxisome proliferation. Rats were then subjected to partial hepatectomy and then maintained for 6 months on a basal diet or one containing 0.05 % phenobarbital. Ciprofibrate treatment did not increase the number or volume of altered hepatic foci (putative preneoplastic lesions). However, ciprofibrate treatment increased liver weights in a dose-dependent manner in rats which did not receive phenobarbital. It is concluded that ciprofibrateinduced peroxisome proliferation is not sufficient to induce initiation, but that a permanent change is produced which results in an increased liver weight.
676 YOUTH CRISIS CENTERS indicated that fully two-thirds of the young people within social servic... more 676 YOUTH CRISIS CENTERS indicated that fully two-thirds of the young people within social service pro-grams were there under pressure from their family, school, or the police. Many youths perceive social service programs as allied with the values of parents, school ...
Pyrex Ò is an ubiquitous material that has attained widespread use in laboratory glassware and ho... more Pyrex Ò is an ubiquitous material that has attained widespread use in laboratory glassware and household utensils due to its properties, cost effectiveness, and ease of fabrication. Despite its importance, the structure of borosilicate glass such as Pyrex Ò is not fully understood. Here, we report high resolution 29 Si, 27 Al, and 11 B magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopic measurements at 9.4 and 19.5 T, combined with 27 Al and 11 B multiple-quantum MAS (MQ-MAS), and 11 B Rotor Assisted Population Transfer (RAPT), to identify structural features in Pyrex Ò . A distribution of Q 4 silicon and aluminum sites is observed, and there is no evidence of five or six coordinated aluminum. The 27 Al quadrupolar coupling constants for the tetrahedral aluminum varied from 3.5 to 4.5 MHz, while the isotropic chemical shifts varied from 50 to 65 ppm. Boron-11 measurements resolve four distinct distributions in boron environments: two identified as tetrahedral, BO 4 , and two as trigonal, BO 3 . Tetrahedral sites are distinguished by different second coordination spheres, e.g., BO 4 (0 B, 4 Si) and BO 4 (1 B, 3 Si), and the trigonal sites based on the symmetry of the boron environments.
Solid-state 17 O magic-angle spinning nuclear magnetic resonance measurements at 19.5 Tesla were ... more Solid-state 17 O magic-angle spinning nuclear magnetic resonance measurements at 19.5 Tesla were performed on
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