bluuebunny/crossref_metadata_2025 huggingface dataset:
Homoepitaxy of ZnO on bulk and thin film substrates by low temperature metal organic chemical vapor deposition using tert-butanol
Authors: Sartel C. , Sallet V. , Lusson A. , Haneche N. , Laroche J. M. , Galtier P. , Rogers D. J. , Hosseini Teherani F.
Published: May 2009

Homoepitaxial growths of ZnO were performed by low pressure metal organic chemical vapor deposition (MOCVD) on both bulk hydrothermal and thin film buffer layers of ZnO grown by pulsed laser deposition on c-sapphire substrates. The surface roughness, photoluminescence, and x-ray diffraction (0002) peak omega rocking-curve line widths for the bulk and thin film substrates were similar prior to MOCVD growth. After MOCVD growth, it was found that the surface morphology, crystallographic quality, and optical properties of the ZnO layers were far superior to those typically observed for heteroepitaxial growth of ZnO layers on c-sapphire by MOCVD. The MOCVD layers were comparable for growths on both the bulk substrate and the thin film buffer layer. Furthermore, no significant impact of carrier gas was observed. The quality of the ZnO layer appeared to be correlated with the surface morphology and the crystalline quality of the substrate rather than being dependent on whether the substrate was in bulk or thin film form.
Metal organic chemical vapor deposition growth and luminescence of ZnO micro- and nanowires
Authors: Falyouni Farid , Benmamas Lotfi , Thiandoume Coumba , Barjon Julien , Lusson Alain , Galtier Pierre , Sallet Vincent
Published: May 2009

One dimensional (1D) ZnO heterostructures were deposited on C-plane sapphire using metal organic chemical vapor deposition at atmospheric pressure. Both catalyst-assisted and catalyst-free processes were investigated. In this latter case, growth parameters such as the substrate temperature, the oxygen/zinc ratio, or the carrier gas nature were varied in order to observe the modification of the film morphology. Different 1D shapes were produced, including rods, tubes, and needles, and were observed by scanning electron microscopy. Photoluminescence spectra reveal sharp excitonic transitions, and cathodoluminescence signals recorded along a ZnO conical needle exhibit a blueshift from the base to the top. The vapor-liquid-solid growth of ZnO nanowires using gold droplets was also successful.
ZnO nanowires prepared by hydrothermal growth followed by chemical vapor deposition for gas sensors
Authors: Kang Dong-Suk , Han Seok Kyu , Kim Jung-Hyun , Yang Sang Mo , Kim Jae Goo , Hong Soon-Ku , Kim Dojin , Kim Hyojin , Song Jung-Hoon
Published: May 2009

Vertical ZnO nanowires with a very high aspect ratio of more than 250 were synthesized by thermal chemical vapor deposition (CVD) on vertical nanowires grown by hydrothermal growth (HG) without using the metal catalyst. A ZnO seed layer grown by sputtering was crucial to synthesize the vertical nanowires in both the CVD and the HG processes. The underlying vertical nanowires grown by the HG process (HG-nanowire) enhanced nucleation of ZnO during the followed ZnO synthesis by CVD. Hydrogen-gas sensitivity was measured from the synthesized ZnO nanowires. High sensitivity of 72% and response time as fast as 30s was observed at 200°C from the vertical ZnO nanowires grown by CVD on the HG-nanowire, which is much higher than the sensitivity value of 50% from the vertical HG-nanowire and the value of 35% from the vertical CVD nanowires without the HG-nanowire. The results indicate that the method synthesizing the vertical ZnO nanowires by combining the HG process and thermal CVD is a very promising way to fabricate both the vertical nanowires and the highly sensitive gas sensors.
Photoconductivity of the two polar surfaces of ZnO
Authors: Yamaguchi Hiroyuki , Komiyama Takao , Chonan Yasunori , Aoyama Takashi
Published: May 2009

Transient photoconductivity of the two polar surfaces of ZnO single crystal has been studied by using a fast-pulse technique. When ZnO crystal was irradiated by an ultraviolet (UV) light pulse, an obvious Dember effect was observed for both polar surfaces. The sign of the Dember effect indicated that the dominant photocarriers were electrons. Additionally, two distinct differences in UV photoconductivity were observed for the two polar surfaces. First, photocurrent Q was much larger for the O surface than for the Zn surface. The ratio of QO to QZn was about 100 when the applied electric field E was perpendicular to the c-axis and about 30 when E was parallel to it. Second, the excitation light intensity I dependence was quite different. While the photocurrent of the O surface was proportional to I, the photocurrent of the Zn surface was proportional to I1∕2. These results indicated that the recombination processes of photocarriers were quite different between O and Zn surfaces; namely, the direct recombination process was dominant at the Zn surface, while the recombination centers were dominant at the O surface.
Investigation of surface and subsurface damage in diamond grinding of optical glass using hybrid copper-resin-bonded diamond wheel
Authors: Zhao Qingliang , Chen Junyun , Yao Jun , Zhou Shangli
Published: May 2009

Hybrid metal-resin-bonded diamond wheel has more advantages for ultraprecision machining of optical glass than the usually used resin- or metal-bonded diamond grinding wheel. In this article, the grinding performance is investigated using the copper-resin-bonded 5-μm-grain-sized diamond wheel via contour grinding assisted with electrolytic in-process dressing. The surface roughness and figure accuracy were measured with an atomic force microscope (AFM) and Taylor–Hobson profilometer, respectively. The subsurface damage was first evaluated by a new method presented in this article, which was realized via observing the subsurface damage by AFM along the magnetorheological finishing polished groove surface. Then a common method was used for measuring the subsurface-damage depth and observing subsurface cracks, which can also prove the feasibility in evaluating the subsurface damage of the new method. Furthermore, the energy-spectrum analysis was used to evaluate the surface and subsurface by an x-ray energy spectrometer. The experimental results show that the ground workpiece (optical glass BK7) with surface roughness of 6–30 nm and subsurface-damage depth of less than 2.2 μm was generated with the hybrid-bonded diamond grinding wheel. The grinding process introduces the carbide element as an impurity into the surface and subsurface. The results indicate that a copper-resin-bonded diamond wheel can generate surface and subsurface integrities of optical glass with high quality.
Use of the concept “area efficiency of emission” in equations describing field emission from large-area electron sources
Authors: Forbes Richard G.
Published: May 2009

In the context of electron emission from surfaces, the area efficiency of emission (α) is defined as the ratio of the effective area of high-density emission (called the notional emission area) to the apparent area of an emitting sample as judged by its geometrical size (called the macroscopic area). For practical large-area field emitters, values of α are always very small in comparison with 1, perhaps often less than 10−6. This article argues that to avoid errors of interpretation, it is best to write the equations that describe cold field electron emission from large-area emitters in forms that explicitly include α. Also, definitions of areas and current densities should be stated with care. It is shown that electrostatic arguments can provide a rough upper limit for α, above which the design of an array of identical postlike emitters becomes inefficient. This upper limit (αmax) is of the order of 2/γ2, where γ is the field enhancement factor for one of these emitters when standing isolated. Practical emitters will normally have α⪡αmax. A qualitative relationship between the onset voltage and α is noted.
Ion beam sputtering of Ta2O5 films on thermoplast substrates as waveguides for biosensors
Authors: Kulisch W. , Gilliland D. , Ceccone G. , Sirghi L. , Rauscher H. , Gibson P. N. , Zürn M. , Bretagnol F. , Rossi F.
Published: May 2009

Tantalum pentoxide thin films have been deposited at room temperature by (dual) ion beam sputtering for applications as waveguides in biosensors. The oxygen partial pressure and the energy of the substrate ion beam were the major parameters varied in ion beam sputtering and dual ion beam sputtering experiments, respectively. For sufficiently high oxygen partial pressures, the films were stoichiometric, free of contaminants, amorphous, and extremely smooth. Ion bombardment of the growing films with Ar+ ions up to 200eV had no significant influence on these properties. The refractive index of stoichiometric films was 2.1±0.1 and the extinction coefficient well below the resolution limit of ellipsometry and UV/visible measurements. By coupling a laser beam via an optical grating into a 150nm thick Ta2O5 layer, the optical losses could be estimated to be below 3dB∕cm. A series of experiments has been carried out to prove that this deposition process is compatible with the use of thermoplast substrates which are sensitive not only to high temperatures but also to ion bombardment and UV radiation. Finally, first experiments are presented to functionalize the surfaces of Ta2O5 films with amine and epoxy groups.
Unique photoluminescence from ZnO grown by eclipse pulsed laser deposition
Authors: Mendelsberg R. J. , Kennedy J. V. , Durbin S. M. , Reeves R. J.
Published: May 2009

Nanostructured ZnO was deposited by eclipse pulsed laser deposition from a metallic Zn target in an oxygen atmosphere. Photoluminescence (PL) was carried out on the structures at liquid helium temperatures. The temperature dependence of the PL as well as the power dependence at 4 K gave insight into the processes governing the light emission from these samples. Free A and B excitonic emission was observed as well as exciton-polariton emission from the upper and lower polariton branches. The low temperature PL was dominated by the I7 exciton, which currently has an unknown chemical origin and is not commonly observed in the PL spectrum of bulk ZnO. Power dependence of the I7 feature showed unique behavior not previously reported. All the other features had nearly linear power dependence while the I7 peak had an emission exponent of 1.53±0.01. Lead was the dominant impurity in the Zn target used to grow the eclipse pulsed laser deposited (EPLD) samples and seemed a likely candidate for the origin of the I7 excitonic peak. Implantation of Pb into bulk ZnO showed no appearance of the I7 feature at 0.01% Pb concentration. As such, Pb may not be the origin of the I7 feature which dominates the PL from the EPLD grown samples. However, due to the complicated interactions of Pb in a ZnO host, it is likely that the Pb is incorporated differently in the implanted bulk and EPLD grown ZnO.
Comparison of ZnO nanostructures grown using pulsed laser deposition, metal organic chemical vapor deposition, and physical vapor transport
Authors: Sandana V. E. , Rogers D. J. , Hosseini Teherani F. , McClintock R. , Bayram C. , Razeghi M. , Drouhin H.-J. , Clochard M. C. , Sallet V. , Garry G. , Falyouni F.
Published: May 2009

This article compares the forms and properties of ZnO nanostructures grown on Si(111) and c-plane sapphire (c-Al2O3) substrates using three different growth processes: metal organic chemical vapor deposition (MOCVD), pulsed laser deposition (PLD), and physical vapor transport (PVT). A very wide range of ZnO nanostructures was observed, including nanorods, nanoneedles, nanocombs, and some novel structures resembelling “bevelled” nanowires. PVT gave the widest family of nanostructures. PLD gave dense regular arrays of nanorods with a preferred orientation perpendicular to the substrate plane on both Si and c-Al2O3 substrates, without the use of a catalyst. X-ray diffraction (XRD) studies confirmed that nanostructures grown by PLD were better crystallized and more highly oriented than those grown by PVT and MOCVD. Samples grown on Si showed relatively poor XRD response but lower wavelength emission and narrower linewidths in PL studies.
Temperature dependence of localization effects of excitons in ZnO∕CdxZn1−xO∕ZnO double heterostructures
Authors: Lange M. , Zippel J. , Benndorf G. , Czekalla C. , Hochmuth H. , Lorenz M. , Grundmann M.
Published: May 2009

Zn O ∕ Cd x Zn 1 − x O double heterostructures grown on a-plane sapphire substrates by pulsed-laser deposition were investigated concerning their photoluminescence properties. The localization of excitons in the CdxZn1−xO alloys were studied and analyzed with temperature dependent photoluminescence measurements from T=2K up to room temperature. The temperature dependence of the Huang–Rhys factor was used to calculate the fraction of strongly localized excitons for this temperature range. The depth of the localization potentials is estimated using two different methods.
Long-Term Survival of
Salmonella enterica
Serovar Typhimurium Reveals an Infectious State That Is Underrepresented on Laboratory Media Containing Bile Salts
Authors: Apel Dmitry , White Aaron P. , Grassl Guntram A. , Finlay B. Brett , Surette Michael G.
Published: May 2009

Cells in desiccated
Salmonella enterica
serovar Typhimurium rdar (
r
ed,
d
ry, and
r
ough) morphotype colonies were examined for culturability and infectivity after 30 months. Culturability decreased only 10-fold; however, cells were underrepresented on
Salmonella
selective media containing bile salts. These cells were mildly attenuated compared to the infectivity of freshly grown cells but still able to cause systemic infections in mice.
In Situ Phylogenetic Structure and Diversity of Wild
Bradyrhizobium
Communities
Authors: Sachs J. L. , Kembel S. W. , Lau A. H. , Simms E. L.
Published: May 2009

Bacteria often infect their hosts from environmental sources, but little is known about how environmental and host-infecting populations are related. Here, phylogenetic clustering and diversity were investigated in a natural community of rhizobial bacteria from the genus
Bradyrhizobium
. These bacteria live in the soil and also form beneficial root nodule symbioses with legumes, including those in the genus
Lotus
. Two hundred eighty pure cultures of
Bradyrhizobium
bacteria were isolated and genotyped from wild hosts, including
Lotus angustissimus
,
Lotus heermannii
,
Lotus micranthus
, and
Lotus strigosus
. Bacteria were cultured directly from symbiotic nodules and from two microenvironments on the soil-root interface: root tips and mature (old) root surfaces. Bayesian phylogenies of
Bradyrhizobium
isolates were reconstructed using the internal transcribed spacer (ITS), and the structure of phylogenetic relatedness among bacteria was examined by host species and microenvironment. Inoculation assays were performed to confirm the nodulation status of a subset of isolates. Most recovered rhizobial genotypes were unique and found only in root surface communities, where little bacterial population genetic structure was detected among hosts. Conversely, most nodule isolates could be classified into several related, hyper-abundant genotypes that were phylogenetically clustered within host species. This pattern suggests that host infection provides ample rewards to symbiotic bacteria but that host specificity can strongly structure only a small subset of the rhizobial community.
Characterization of Three New
Azotobacter vinelandii
Alginate Lyases, One of Which Is Involved in Cyst Germination
Authors: Gimmestad Martin , Ertesvåg Helga , Heggeset Tonje Marita Bjerkan , Aarstad Olav , Svanem Britt Iren Glærum , Valla Svein
Published: May 2009

Alginates are polysaccharides composed of 1-4-linked β-
d
-mannuronic acid and α-
l
-guluronic acid. The polymer can be degraded by alginate lyases, which cleave the polysaccharide using a β-elimination reaction. Two such lyases have previously been identified in the soil bacterium
Azotobacter vinelandii
, as follows: the periplasmic AlgL and the secreted bifunctional mannuronan C-5 epimerase and alginate lyase AlgE7. In this work, we describe the properties of three new lyases from this bacterium, AlyA1, AlyA2, and AlyA3, all of which belong to the PL7 family of polysaccharide lyases. One of the enzymes, AlyA3, also contains a C-terminal module similar to those of proteins secreted by a type I secretion system, and its activity is stimulated by Ca
2+
. All three enzymes preferably cleave the bond between guluronic acid and mannuronic acid, resulting in a guluronic acid residue at the new reducing end, but AlyA3 also degrades the other three possible bonds in alginate. Strains containing interrupted versions of
alyA1
,
alyA3
, and
algE7
were constructed, and their phenotypes were analyzed. Genetically pure
alyA2
mutants were not obtained, suggesting that this gene product may be important for the bacterium during vegetative growth. After centrifugation, cultures from the
algE7
mutants form a large pellet containing alginate, indicating that AlgE7 is involved in the release of alginate from the cells. Upon encountering adverse growth conditions,
A. vinelandii
will form a resting stage called cyst. Alginate is a necessary part of the protective cyst coat, and we show here that strains lacking
alyA3
germinate poorly compared to wild-type cells.
Analysis of Achromobactin Biosynthesis byPseudomonas syringaepv. syringae B728a
Authors: Berti Andrew D. , Thomas Michael G.
Published: May 2009

Pseudomonas syringaepv. syringae B728a is known to produce the siderophore pyoverdine under iron-limited conditions. It has also been proposed that this pathovar has the ability to produce a second siderophore, achromobactin. Here we present genetic and biochemical evidence supporting the hypothesis thatP. syringaepv. syringae B728a produces both of these siderophores. We show that strains unable to synthesize either pyoverdine or achromobactin are unable to grow under iron-limiting conditions, which is consistent with these two molecules being the only siderophores synthesized byP. syringaepv. syringae B728a. Enzymes associated with achromobactin biosynthesis were purified and analyzed for substrate recognition. We showed that AcsD, AcsA, and AcsC together are able to condense citrate, ethanolamine, 2,4-diaminobutyrate, and α-ketoglutarate into achromobactin. Replacement of ethanolamine with ethylene diamine or 1,3-diaminopropane in these reactions resulted in the formation of achromobactin analogs that were biologically active. This work provides insights into the biosynthetic steps in the formation of achromobactin and is the first in vitro reconstitution of achromobactin biosynthesis.
ASIC1 contributes to pulmonary vascular smooth muscle store-operated Ca2+entry
Authors: Jernigan Nikki L. , Paffett Michael L. , Walker Benjimen R. , Resta Thomas C.
Published: May 2009

Acid-sensing ion channels (ASIC) are voltage-insensitive, cationic channels that have recently been identified in vascular smooth muscle (VSM). It is possible that ASIC contribute to vascular reactivity via Na+and Ca2+conductance; however, their function in VSM is largely unknown. In pulmonary VSM, store-operated Ca2+entry (SOCE) plays a significant role in vasoregulatory mechanisms such as hypoxic pulmonary vasoconstriction and receptor-mediated arterial constriction. Therefore, we hypothesized that ASIC contribute to SOCE in pulmonary VSM. We examined SOCE resulting from depletion of intracellular Ca2+stores with cyclopiazonic acid in isolated small pulmonary arteries and primary cultured pulmonary arterial smooth muscle cells by measuring 1) changes in VSM [Ca2+]iusing fura-2 indicator dye, 2) Mn2+quenching of fura-2 fluorescence, and 3) store-operated Ca2+and Na+currents using conventional whole cell patch-clamp configuration in voltage-clamp mode. The role of ASIC was assessed by the use of the ASIC inhibitors, amiloride, benzamil, and psalmotoxin 1, or siRNA directed towards ASIC1, ASIC2, or ASIC3 isoforms. We found that store-operated VSM [Ca2+]iresponses, Mn2+influx, and inward cationic currents were attenuated by either pharmacological ASIC inhibition or treatment with ASIC1 siRNA. These data establish a unique role for ASIC1 in mediating SOCE in pulmonary VSM and provide new insight into mechanisms of VSM Ca2+entry and pulmonary vasoregulation.
Vaccine Adherence in Adolescents
Authors: Lehmann Corinne , Benson Paul A. S.
Published: May 2009

Although a number of routine and catch-up vaccinations are currently recommended for adolescents, coverage rates of these vaccines are currently suboptimal. Routine recommended immunizations for this cohort include vaccines for influenza, human papillomavirus, and meningococcal disease, as well as a booster for tetanus, diphtheria, and acellular pertussis. Adolescence is also a critical period for administration of catch-up vaccines for those not fully immunized during childhood. Adolescents who do not seek appropriate preventive healthcare are at risk for significant morbidity and possible mortality. Increasing adolescent adherence to recommended vaccine schedules presents a challenge and opportunity for pediatricians and public health advocates. This article outlines barriers to vaccine compliance among adolescents and discusses strategies to increase vaccine uptake.
Health Supervision Visits of Very Young Children: Time Addressing 3 Key Topics
Authors: Manning Kristie M. , Ariza Adolfo J. , Massimino Tara K. , Binns Helen J. ,   for the Pediatric Practice Research Group
Published: May 2009

Objective. To describe the time and actions on 3 key health topics during health supervision (HS) visits of children aged 0 to 1 years. Method. HS visits were observed at 5 offices. Parents provided demographics and children’s measurements were obtained. Using special computer software, visits were observed for frequency and time for growth measurements, charting and interpretations, and for discussions on growth, diet, and safety. Results. A total of 128 visits were analyzed. Almost all children had weight (100%) and height (98%) measured and >80% had weight-for-age and height-for-age plotted. Growth interpretation (weight-for-height) was determined for 1 child. Nearly all visits included discussions of growth (88%), diet (97%), and safety (84%). When a topic was addressed, median times were as follows: growth, 9 seconds; diet, 42 seconds; and safety, 22 seconds. Median time on all 3 topics was 86 seconds. Conclusion. Growth, diet, and safety are frequently, but briefly, discussed at HS visits of young children.
Behavioral Treatment of Trichotillomania and Trichophagia in a 29-Month-Old Girl
Authors: Rahman Omar , Toufexis Megan , Murphy Tanya K. , Storch Eric A.
Published: May 2009

Early childhood trichotillomania (TTM) has often been considered to be benign. However, untreated early childhood TTM can have significant negative physical and psychological consequences. This report describes the behavioral treatment of a 29-month-old girl with TTM. Treatment consisted of 14 daily sessions of behavioral intervention, followed by 3 consecutive days of follow-up treatment conducted 7 weeks after the end of initial treatment. The hair pulling was addressed by using reinforcers for not pulling, provided at intervals of increasing length. At the end of initial treatment, the hair pulling improved significantly. At follow-up, although some of the initial treatment gains were reduced, the patient maintained significant improvement compared with baseline.
Feasibility and Acceptability of a 1-Page Tool to Help Physicians Assess and Discuss Obesity With Parents of Preschoolers
Authors: Woolford Susan J. , Clark Sarah J. , Ahmed Sana , Davis Matthew M.
Published: May 2009

Objective. To assess the feasibility and acceptability of a brief tool to help pediatricians communicate with parents of preschoolers about obesity risk, prevention, and treatment. Methods. The 2-sided Assessment and Targeted Messages (ATM) tool developed by the investigators included sections to assess nutrition and physical activity, self-efficacy and readiness-to-change, obesity-related family history, and treatment/prevention recommendations. Twenty-five pediatricians were recruited to use the ATM and then surveyed regarding their opinions of its feasibility and acceptability. Results. Response rate was 60%. Most ATM features were considered somewhat or very useful by the majority of respondents. The majority of physicians (62%) indicated that they were somewhat likely to use the ATM in the future, with only 23% indicating that they were very likely to use it. The greatest barrier to its use was time. Conclusion. Pediatricians considered the ATM tool moderately feasible and acceptable. Time-efficient methods to help physicians address obesity should be explored.
Being a Reserve Soldier
Authors: Griffith James
Published: May 2009

Drawing on social identity theory, the present article examines the extent to which soldier identification with the small unit is related to outcomes having increased importance to reserve military service. Measures of social identity have stronger associations with unit membership, whereas measures of personal identity do not. Soldiers’ reports of positive experiences when first entering the unit are more strongly and positively related to measures of social identity than to measures of personal identity. Measures of social identity show positive relationships with group-relevant outcomes, such as commitment to the unit and perceived readiness of the unit and fellow soldiers. Measures of personal identity show positive relationships with individually relevant outcomes, such as reporting for duty for contractual reasons and letting their families down and perceived personal readiness for combat. Results imply improving specific small-unit relations and developing abstract beliefs to increase reservists’ perceived readiness and commitment to their part-time military service.
Veterans, the Vietnam Era, and Marital Dissolution
Authors: Cohen Jere , Segal Mady Wechsler
Published: May 2009

Event history analysis of 2,241 married males from James Coleman’s Adolescent Society study adds to the evidence that military service, even in the Vietnam era, has not been a significant factor in the breakup of veterans’ marriages. Rather, veterans’ risk of divorce in the fifteen years ending in 1973 hinged on some of the same factors that affect divorce probabilities anywhere and at any time, such as education, religion, number of children, and an early birth. Call and Teachman’s finding that service increases family stability is seen as applicable to high-divorce states, while the present finding that it makes “no difference” applies in states with average divorce rates.
Rhetoric of Innovation Policy Making in Hong Kong Using the Innovation Systems Conceptual Approach
Authors: Sharif Naubahar
Published: May 2009

Since its introduction in the 1980s, use of the innovation systems (IS) conceptual approach has been growing, particularly on the part of national governments including, recently, the Hong Kong Government. In 2004, the Hong Kong Government set forth a ‘‘new strategy’’ for innovation and technology policy making. Because it marked a significant break from the past (characterized by a laissez-faire Government attitude), it was necessary to convince a wider audience to accept this new strategy, a strategy that included the IS conceptual approach. Adopting a science and technology studies (S&TS) perspective, I show how the IS conceptual approach is being used as a rhetorical resource by the Hong Kong Government in its innovation and technology policy making in an effort to persuade its perceived audience of the efficacy of its new strategy for its policies—policies that are in fact unrelated to the basic precepts of the IS conceptual approach. The case provides a cautionary tale in the ways in which policy makers transform scholarly work and scientific discovery into rhetorical instruments in support of a political agenda.
Reference accuracy in four rehabilitation journals
Authors: Unver Bayram , Senduran Meric , Unver Kocak Fatma , Gunal Izge , Karatosun Vasfi
Published: May 2009

Objective: To investigate the incidence of reference errors in major peer-reviewed general physical therapy and rehabilitation journals (American Journal of Physical Medicine and Rehabilitation (AJPMR), Archives of Physical Medicine and Rehabilitation (APMR), Clinical Rehabilitation (CR) and Physical Therapy (PT)).

Design: Descriptive, comparative.

Main outcome measures: All issues of the AJPMR, APMR, CR and PT between 2003 and 2007 were studied. For each journal, references from articles were consecutively numbered, and using a random number generator, 100 references were selected from each journal. For each reference, ease of retrieval on MEDLINE and the presence of citation errors were noted. If discrepancies were identified, the reference was compared with the original publication. Two observers independently evaluated each reference for citation errors.

Results: The total number of citations with errors among all published journals was 123 (30.7%). The reference error rates by journal ranged from 23% to 44%. Most errors (48.0%) occurred in the author element, followed by the title (31.7%), journal (8.9%), page (5.7%), year (4.1%), and volume (1.6%). Only 8 (2%) were likely to make retrieval of the reference difficult.

Conclusions: Errors in references still appear in current physical therapy and rehabilitation literature, but most are not severe.
Patellar taping affects vastus medialis obliquus activation in subjects with patellofemoral pain before and after quadriceps muscle fatigue
Authors: Ng Gabriel YF , Wong Pamela YK
Published: May 2009

Objective: To investigate the effects of patellar taping on the electromyographic onset of vastus medialis obliquus and vastus lateralis, and their magnitudes of reflex contraction before and after quadriceps muscle fatigue in subjects with patellofemoral pain.

Methods: Sixteen adults (5 males) diagnosed with patellofemoral pain were studied. The timing of surface electromyography onset and magnitude of vastus medialis obliquus and vastus lateralis contractions were measured during a postero-anterior knee perturbation test. The tests were conducted in random order under three conditions of real taping, placebo taping and no taping. Afterwards, the subjects performed knee extension exercises until fatigue and the above tests were repeated, so as to examine the effects of patellar taping in a muscle fatigued condition.

Results: There was no significant difference in electromyographic onset timing of vastus medialis obliquus and vastus lateralis or in the amplitude of vastus lateralis contraction among the different testing conditions. For vastus medialis obliquus amplitude, however, it was significantly higher in the no taping than the real taping condition regardless of the state of fatigue (P = 0.013).

Conclusions: The present study suggests that patellar taping might not enhance the temporal activation of vastus medialis obliquus in subjects with patellofemoral pain before and after muscle fatigue. Furthermore, vastus medialis obliquus contraction might be inhibited by patellar taping.
Open Reconstruction of Large Bony Glenoid Erosion with Allogeneic Bone Graft for Recurrent Anterior Shoulder Dislocation
Authors: Weng Pei-Wei , Shen Hsain-Chung , Lee Hsieh-Hsing , Wu Shing-Sheng , Lee Chian-Her
Published: May 2009

Background

Severe glenoid bone loss in recurrent anterior glenohumeral instability is rare and difficult to treat.

Purpose

The authors present a surgical technique using allogeneic bone grafting for open anatomic glenoid reconstruction in addition to the capsular shift procedure.

Study Design

Case series; Level of evidence, 4.

Methods

Nine consecutive patients with a history of recurrent anterior shoulder instability underwent reconstruction of large bony glenoid erosion with a femoral head allograft combined with an anteroinferior capsular shift procedure. Preoperative computed tomographic and arthroscopic evaluation was performed to confirm a ≥120° osseous defect of the anteroinferior quadrant of the glenoid cavity, which had an “inverted-pear” appearance. Patients were followed for at least 4.5 years (range, 4.5-14). Serial postoperative radiographs were evaluated. Functional outcomes were assessed using Rowe scores.

Results

All grafts showed bony union within 6 months after surgery. The mean Rowe score improved to 84 from a preoperative score of 24. The mean loss of external rotation was 7° compared with the normal shoulder. One subluxation and 1 dislocation occurred after grand mal seizures during follow-up. These 2 patients regained shoulder stability after closed reduction. The remaining patients did not report recurrent instability. All patients resumed daily activities without restricted motion.

Conclusion

This technique for open reconstruction is viable for the treatment of recurrent anterior glenohumeral instability with large bony glenoid erosion.
The gap between scientists and journalists: the case of mercury science in Québec’s press
Authors: Maillé Marie-Ève , Saint-Charles Johanne , Lucotte Marc
Published: May 2009

This research aimed to better understand the gap between journalists and scientists in the context of the media coverage of an environmental issue in Québec (Canada). Through in-depth interviews with journalists and scientists, we were able to identify different sources of frustration felt by both protagonists, notably the question of the scientists’ revision of the journalists’ text, the journalists’ lack of accuracy, and the problem of different time frames in the media and the scientific worlds. This study also offered insights for bridging the gaps.
Diving in magma: how to explore controversies with actor-network theory
Authors: Venturini Tommaso
Published: May 2009

The cartography of controversies is a set of techniques to explore and visualize issues. It was developed by Bruno Latour as a didactic version of Actor-Network Theory to train college students in the investigation of contemporary socio-technical debate. The scope and interest of such cartography, however, exceed its didactic origin. Adopted and developed in several universities in Europe and the US, the cartography of controversies is today a full research method, though, unfortunately, not a much documented one. To fill this lack of documentation, we draw on our experience as Latour’s teaching assistant, to introduce some of the main techniques of the social cartographer toolkit. In particular, in these pages we will focus on exploration, leaving the discussion of visualization tools to a further paper.
The Hedgehog receptor Patched1 regulates myeloid and lymphoid progenitors by distinct cell-extrinsic mechanisms
Authors: Siggins Sarah L. , Nguyen Nhu-Y N. , McCormack Matthew P. , Vasudevan Sumitha , Villani Rehan , Jane Stephen M. , Wainwright Brandon J. , Curtis David J.
Published: May 2009

Hedgehog (Hh) ligands bind to the Patched1 (Ptch1) receptor, relieving repression of Smoothened, which leads to activation of the Hh signaling pathway. Using conditional Ptch1 knockout mice, the aim of this study was to determine the effects of activating the Hh signaling pathway in hematopoiesis. Surprisingly, hematopoietic-specific deletion of Ptch1 did not lead to activation of the Hh signaling pathway and, consequently, had no phenotypic effect. In contrast, deletion of Ptch1 in nonhematopoietic cells produced 2 distinct hematopoietic phenotypes. First, activation of Hh signaling in epithelial cells led to apoptosis of lymphoid progenitors associated with markedly elevated levels of circulating thymic stromal lymphopoietin. Second, activation of Hh signaling in the bone marrow cell niche led to increased numbers of lineage-negative c-kit+ Sca-1+ bone marrow cells and mobilization of myeloid progenitors associated with a marked loss of osteoblasts. Thus, deletion of Ptch1 leads to hematopoietic effects by distinct cell-extrinsic mechanisms rather than by direct activation of the Hh signaling pathway in hematopoietic cells. These findings have important implications for therapeutics designed to activate the Hh signaling pathway in hematopoietic cells including hematopoietic stem cells.
Principal component spectral analysis
Authors: Guo Hao , Marfurt Kurt J. , Liu Jianlei
Published: May 2009

Spectral decomposition methods help illuminate lateral changes in porosity and thin-bed thickness. For broadband data, an interpreter might generate 80 or more somewhat redundant amplitude and phase spectral components spanning the usable seismic bandwidth at [Formula: see text] intervals. Large numbers of components can overload not only the interpreter but also the display hardware. We have used principal component analysis to reduce the multiplicity of spectral data and enhance the most energetic trends inside the data. Each principal component spectrum is mathematically orthogonal to other spectra, with the importance of each spectrum being proportional to the size of its corresponding eigenvalue. Principal components are ideally suited to identify geologic features that give rise to anomalous moderate- to high-amplitude spectra. Unlike the input spectral magnitude and phase components, the principal component spectra are not direct indicators of bed thickness. By combining the variability of multiple components, principal component spectra highlight stratigraphic features that can be interpreted using a seismic geomorphology workflow. By mapping the three largest principal components using the three primary colors of red, green, and blue, we could represent more than 80% of the spectral variance with a single image. We have applied and validated this workflow using a broadband data volume containing channels draining an unconformity, which was acquired over the Central Basin Platform, Texas, U.S.A. Principal component analysis reveals a channel system with only a few output data volumes. The same process provides the interpreter with flexibility to remove any unwanted high-amplitude geologic trends or random noise from the original spectral components by eliminating those principal components that do not aid in delineation of prospective features with their interpretation during the reconstruction process.
Superwide-angle one-way wave propagator and its application in imaging steep salt flanks
Authors: Jia Xiaofeng , Wu Ru-Shan
Published: May 2009

One-way wave propagators have been used extensively in forward and inverse problems. The advantages of one-way wave propagators are the fast speed of computation and the large savings in computer resources. However, regular one-way wave propagators have inherent angle limitation to within 90° of the preferred direction (e.g., [Formula: see text]-direction). We propose to overcome the limitation by a superwide-angle one-way method, which combines and interpolates two orthogonally propagated one-way wavefields in the 2D case. A weight function determined by the propagation angle is employed to combine the two one-way wavefields. In the current implementation, we use the wavefield gradient to estimate the propagation angle. Numerical experiments show that the proposed method has accurate superwide-angle [Formula: see text] propagation and can model turning waves well. By applying the superwide-angle one-way wave propagator on several synthetic model data sets, we can demonstrate the validity of the method in imaging steep and overhanging salt flanks.
Histological evaluation of internally-fixed osteochondral lesions of the knee
Authors: Adachi N. , Motoyama M. , Deie M. , Ishikawa M. , Arihiro K. , Ochi M.
Published: May 2009

We evaluated the histological changes before and after fixation in ten knees of ten patients with osteochondritis dissecans who had undergone fixation of the unstable lesions. There were seven males and three females with a mean age of 15 years (11 to 22). The procedure was performed either using bio-absorbable pins only or in combination with an autologous osteochondral plug. A needle biopsy was done at the time of fixation and at the time of a second-look arthroscopy at a mean of 7.8 months (6 to 9) after surgery.

The biopsy specimens at the second-look arthroscopy showed significant improvement in the histological grading score compared with the pre-fixation scores (p < 0.01). In the specimens at the second-look arthroscopy, the extracellular matrix was stained more densely than at the time of fixation, especially in the middle to deep layers of the articular cartilage.

Our findings show that articular cartilage regenerates after fixation of an unstable lesion in osteochondritis dissecans.
Arthroscopic excision of a giant-cell tumour of the ligamentum teres
Authors: Singh P. J. , Constable L. , O’Donnell J.
Published: May 2009

Primary giant-cell tumour of soft tissue arising in the ligamentum teres has not been previously described. We report a case of such a tumour in a 46-year-old woman. The lesion was only detected at the time of hip arthroscopy despite pre-operative MRI being performed. It was successfully excised arthroscopically with resolution of the symptoms.
Cervical spinal disc replacement
Authors: Denaro V. , Papalia R. , Denaro L. , Di Martino A. , Maffulli N.
Published: May 2009

Cervical spinal disc replacement is used in the management of degenerative cervical disc disease in an attempt to preserve cervical spinal movement and to prevent adjacent disc overload and subsequent degeneration. A large number of patients have undergone cervical spinal disc replacement, but the effectiveness of these implants is still uncertain. In most instances, degenerative change at adjacent levels represents the physiological progression of the natural history of the arthritic disc, and is unrelated to the surgeon. Complications of cervical disc replacement include loss of movement from periprosthetic ankylosis and ossification, neurological deficit, loosening and failure of the device, and worsening of any cervical kyphosis. Strict selection criteria and adherence to scientific evidence are necessary. Only prospective, randomised clinical trials with long-term follow-up will establish any real advantage of cervical spinal disc replacement over fusion.
Bilateral total hip replacement in osteogenesis imperfecta with hyperplastic callus
Authors: Ramaswamy R. , Kosashvili Y. , Cameron H.
Published: May 2009

Osteogenesis imperfecta is a rare inherited disorder of connective tissue which may present with recurrent fractures which are prone to nonunion and malunion resulting in deformity. Some patients develop osteoarthritis of the hip. Formation of hyperplastic callus after recurrent fractures may deform the shape of the femur and preclude the use of standard implants at joint replacement. Replacement can thus be technically demanding.

We present a case of bilateral hip replacement in a patient with osteogenesis imperfecta and hyperplastic callus which was treated by the use of long femoral allografts and cemented femoral stems.
The Medial Rotation total knee replacement
Authors: Mannan K. , Scott G.
Published: May 2009

We describe the survivorship of the Medial Rotation total knee replacement (TKR) at ten years in 228 cemented primary replacements implanted between October 1994 and October 2006, with their clinical and radiological outcome. This implant has a highly congruent medial compartment, with the femoral component represented by a portion of a sphere which articulates with a matched concave surface on the medial side of the tibial insert.

There were 78 men (17 bilateral TKRs) and 111 women (22 bilateral TKRs) with a mean age of 67.9 years (28 to 90). All the patients were assessed clinically and radiologically using the American Knee Society scoring systems. The mean follow-up was for six years (1 to 13) with only two patients lost to follow-up and 34 dying during the period of study, one of whom had required revision for infection.

There were 11 revisions performed in total, three for aseptic loosening, six for infection, one for a periprosthetic fracture and one for a painful but well-fixed replacement performed at another centre.

With revision for any cause as the endpoint, the survival at ten years was 94.5% (95% CI 85.1 to 100), and with aseptic loosening as the endpoint 98.4% (95% CI 93 to 100). The mean American Knee Society score improved from 47.6 (0 to 88) to 72.2 (26 to 100) and for function from 45.1 (0 to 100) to 93.1 (45 to 100). Radiological review failed to detect migration in any of the surviving knees.

The clinical and radiological results of the Medial Rotation TKR are satisfactory at ten years. The increased congruence of the medial compartment has not led to an increased rate of loosening and continued use can be supported.
Traumatic separation of the distal epiphysis of the humerus sustained at birth
Authors: Jacobsen S. , Hansson G. , Nathorst-Westfelt J.
Published: May 2009

We reviewed the clinical and radiological results of six patients who had sustained traumatic separation of the distal epiphysis of the humerus at birth.

The correct diagnosis was made from plain radiographs and often supplemented with ultrasonography, MRI and arthrography. An orthopaedic surgeon saw two patients within two days of birth, and the other four were seen at between nine and 30 days. The two neonates underwent unsuccessful attempts at closed reduction. In the remaining patients, seen after the age of eight days, no attempt at reduction was made. All six displaced fractures were immobilised in a cast with the elbow at 90° of flexion and the forearm pronated.

When seen at a mean of 58 months (16 to 120) after injury, the clinical and radiological results were excellent in five patients, with complete realignment of the injury. In one patient the forearm lay in slightly reduced valgus with the elbow in full extension.

Traumatic separation of the distal epiphysis of the humerus may be missed on the maternity wards and not diagnosed until after discharge from hospital. However, even when no attempt is made to reduce the displaced epiphysis, a good clinical result can be expected.
The knee in full flexion
Authors: Pinskerova V. , Samuelson K. M. , Stammers J. , Maruthainar K. , Sosna A. , Freeman M. A. R.
Published: May 2009

There has been only one limited report dating from 1941 using dissection which has described the tibiofemoral joint between 120° and 160° of flexion despite the relevance of this arc to total knee replacement. We now provide a full description having examined one living and eight cadaver knees using MRI, dissection and previously published cryosections in one knee.

In the range of flexion from 120° to 160° the flexion facet centre of the medial femoral condyle moves back 5 mm and rises up on to the posterior horn of the medial meniscus. At 160° the posterior horn is compressed in a synovial recess between the femoral cortex and the tibia. This limits flexion. The lateral femoral condyle also rolls back with the posterior horn of the lateral meniscus moving with the condyle. Both move down over the posterior tibia at 160° of flexion.

Neither the events between 120° and 160° nor the anatomy at 160° could result from a continuation of the kinematics up to 120°. Therefore hyperflexion is a separate arc. The anatomical and functional features of this arc suggest that it would be difficult to design an implant for total knee replacement giving physiological movement from 0° to 160°.
In Praise of Sneaky Poo: A Case, Four Whites, and a Missing Narrative
Authors: Grimwade Jo
Published: May 2009

Sneaky Poo (1984) announced Michael White, the second order cyberneticist, to the world. But there were several versions of both Sneaky Poo and White. This paper pays homage to Sneaky and critiques White's contribution to family therapy. A recent case is reported.
Michael White Memorial
Authors: Aguis Tim
Published: May 2009

The following is a memorial speech delivered at the Maugham Uniting Church by the author in memory of Michael White.