bluuebunny/crossref_metadata_2025 huggingface dataset:
Clustered car‐following strategy for improving car‐following stability under Cooperative Vehicles Infrastructure Systems
Authors: Shi Yun‐Feng , Yang Li‐Cai , Hao Shen‐Xue , Liu Qian
Published: October 2015

In this study, the problem of car‐following stability is considered. This study presents a clustered car‐following strategy based on inter‐vehicle communications (IVCs), which contributes to derive a more accurate feedback control for improving the stability. In order to maintain car‐following stability, two conditions are considered, which are based on the control theory and a modified optimal velocity car‐following model. In simulations, the results demonstrate that the strategy is effective on the stability of car‐following, and the effect becomes more obvious as the market penetration rates of IVC‐equipped vehicles increase. Even in low market penetration rate (5%), the proposed strategy has significant influence on the stability and the recovering time.
Zusammenhang von Auslandseinsätzen und Tabakabhängigkeit bei Soldaten
Authors: Wesemann U. , Schura R. , Kowalski J. , Kropp S. , Danker-Hopfe H. , Rau H. , Ströhle A. , Thiele J. , Zimmermann P.
Published: October 2015

Ziel der Studie: Rauchen ist ein hoher vermeidbarer Risikofaktor. Diese Studie untersucht, ob militärische Auslandseinsätze, im Vergleich zur Einsatzvorbereitung, das Risiko mit dem Rauchen zu beginnen erhöhen, die Tabakabhängigkeit steigern und ob sich Moderatorvariablen zum Rauchverhalten identifizieren lassen.

Methodik: Die Studie wurde an 2 Panzergrenadierbataillonen mit N=264 Soldaten durchgeführt. Die Einsatzgruppe absolvierte einen Auslandseinsatz in Afghanistan, die Vergleichsgruppe nahm währenddessen an einer Einsatzvorbereitung teil. Zu 3 Messzeitpunkten wurden Tabakabhängigkeit, posttraumatische Symptome, Depression und Stress gemessen. Die erste Datenerhebung erfolgte vor und die dritte Erhebung nach dem Auslandseinsatz bzw. der Einsatzvorbereitung. Die Messung zum zweiten Messzeitpunkt erfolgte während des Auslandseinsatzes bzw. der Einsatzvorbereitung.

Ergebnisse: Die Prävalenzrate der rauchenden Soldaten betrug 56,4%. 51,1% (n=135) aller untersuchten Soldaten rauchten mehr als 20 Zigaretten pro Tag. Für die Einsatzgruppe zeigte sich im Vergleich zur Vergleichsgruppe ein signifikanter Anstieg der mittels Fagerström-Test erfassten Tabakabhängigkeit vom ersten zum dritten Messzeitpunkt (p=0,040). In beiden Gruppen gab es während des Untersuchungszeitraums keine erhöhte Anzahl von Soldaten, die mit dem Rauchen begannen (χ²<1; n. s.). Moderatorvariablen auf das Rauchen wurden nicht gefunden, aber es gab einen signifikanten Anstieg in den posttraumatischen Belastungssymptomen bei der Einsatzgruppe (p=0,006).

Schlussfolgerung: Eventuell lässt sich der Anstieg der Tabakabhängigkeit für die Einsatzgruppe auf die spezifischen Belastungen des Einsatzes zurückführen. Wenn sich die hohen Raucherquoten auch in anderen Truppengattungen zeigen, sollten vermehrt Entwöhnungsprogramme angeboten werden.
Modeling of quasi-ballistic transport in nanowire metal-oxide-semiconductor field-effect transistors
Authors: Lee Yeonghun , Kakushima Kuniyuki , Natori Kenji , Iwai Hiroshi
Published: October 2015

We developed a semi-analytical quasi-ballistic transport model for the nanowire metal-oxide-semiconductor field-effect transistors, dealing with finite lengths of source, channel, and drain. For the modeling, we used a combination of one-flux scattering matrices and analytical solutions of Boltzmann transport equations. The developed model was in quantitatively good agreement with numerical results, and well represented intermediate-scaled devices. In addition, we illustrated that the finite source seriously affect the distribution function of the carriers injected from the source, and the finite drain does for the backscattering into the channel from the drain. Finally, our model and results would help to understand physical aspects regarding quasi-ballistic transport in nanoscale devices.
Study of energy transfer between molecules placed in the vicinity of a bimetal composite nanoparticle
Authors: Daneshfar Nader
Published: October 2015

In this study, the problem of energy transfer between two molecules near a bimetallic composite nanoparticle is investigated. The influence of the interaction between metal particles on the intermolecular energy is studied, because when two metal nanoparticles are placed close to each other, their plasmons coupling giving rise to new features. On the other hand, we discuss the transfer of resonance energy between donor and acceptor molecules (a single donor and a single acceptor) in the presence of a nanocomposite containing gold and silver nanoparticles based on the Maxwell-Garnett effective medium theory and within the quasistatic limit. We show that the interaction energy strongly depends on the particle size, the filling factor of metal particles, the intermolecular distance (the distance between the donor and acceptor molecules), and the dielectric constant of host matrix.
Influence of temperature on spin polarization dynamics in dilute nitride semiconductors—Role of nonparamagnetic centers
Authors: Baranowski M. , Misiewicz J.
Published: October 2015

We report theoretical studies of spin polarization dynamics in dilute nitride semiconductors. We develop a commonly used rate equation model [Lagarde et al., Phys. Status Solidi A 204, 208 (2007) and Kunold et al. Phys. Rev. B 83, 165202 (2011)] to take into account the influence of shallow localizing states on the temperature dependence of spin polarization dynamics and a spin filtering effect. Presented investigations show that the experimentally observed temperature dependence of a spin polarization lifetime in dilute nitrides can be related to the electron capture process by shallow localizing states without paramagnetic properties. This process reduces the efficiency of spin filtering effect by deep paramagnetic centers, especially at low temperatures.
Decoupling optical and electronic optimization of organic solar cells using high-performance temperature-stable TiO2/Ag/TiO2 electrodes
Authors: Kim Kwang-Dae , Pfadler Thomas , Zimmermann Eugen , Feng Yuyi , Dorman James A. , Weickert Jonas , Schmidt-Mende Lukas
Published: October 2015

An electrode structured with a TiO2/Ag/TiO2 (TAT) multilayer as indium tin oxide (ITO) replacement with a superior thermal stability has been successfully fabricated. This electrode allows to directly tune the optical cavity mode towards maximized photocurrent generation by varying the thickness of the layers in the sandwich structure. This enables tailored optimization of the transparent electrode for different organic thin film photovoltaics without alteration of their electro-optical properties. Organic photovoltaic featuring our TAT multilayer shows an improvement of ∼12% over the ITO reference and allows power conversion efficiencies (PCEs) up to 8.7% in PTB7:PC71BM devices.
Big data opportunities and challenges for assessing multiple stressors across scales in aquatic ecosystems
Authors: Dafforn K. A. , Johnston E. L. , Ferguson A. , Humphrey C.L. , Monk W. , Nichols S. J. , Simpson S. L. , Tulbure M. G. , Baird D. J.
Published: October 2015

Aquatic ecosystems are under threat from multiple stressors, which vary in distribution and intensity across temporal and spatial scales. Monitoring and assessment of these ecosystems have historically focussed on collection of physical and chemical information and increasingly include associated observations on biological condition. However, ecosystem assessment is often lacking because the scale and quality of biological observations frequently fail to match those available from physical and chemical measurements. The advent of high-performance computing, coupled with new earth observation platforms, has accelerated the adoption of molecular and remote sensing tools in ecosystem assessment. To assess how emerging science and tools can be applied to study multiple stressors on a large (ecosystem) scale and to facilitate greater integration of approaches among different scientific disciplines, a workshop was held on 10–12 September 2014 at the Sydney Institute of Marine Sciences, Australia. Here we introduce a conceptual framework for assessing multiple stressors across ecosystems using emerging sources of big data and critique a range of available big-data types that could support models for multiple stressors. We define big data as any set or series of data, which is either so large or complex, it becomes difficult to analyse using traditional data analysis methods.
Probing exoplanet clouds with optical phase curves
Authors: Muñoz Antonio García , Isaak Kate G.
Published: October 2015

Significance

We investigate the potential of optical phase curves for the characterization of exoplanet clouds. In the case of the low-density, close-in giant planet Kepler-7b, its phase curve reveals that the planet clouds are optically thick and composed of poorly absorbing condensates. We also constrain the cloud particle size, which is an important parameter in the study of the photochemistry, wind dynamics, and cloud microphysics of the planet atmosphere. Our work establishes a valuable framework within which to investigate exoplanet atmospheres using upcoming flagship space missions such as the European Space Agency’s
CHEOPS
and
PLATO
and NASA’s
TESS
, which will all fly within the decade.
The adherens junctions control susceptibility to
Staphylococcus aureus
α-toxin
Authors: Popov Lauren M. , Marceau Caleb D. , Starkl Philipp M. , Lumb Jennifer H. , Shah Jimit , Guerrera Diego , Cooper Rachel L. , Merakou Christina , Bouley Donna M. , Meng Wenxiang , Kiyonari Hiroshi , Takeichi Masatoshi , Galli Stephen J. , Bagnoli Fabio , Citi Sandra , Carette Jan E. , Amieva Manuel R.
Published: October 2015

Significance

Staphylococcus aureus
is a major cause of invasive bacterial infection. One prominent virulence factor is α-toxin, a protein that injures the cell by forming a damaging pore across the cell membrane. We conducted a genetic screen to identify host factors that control susceptibility to α-toxin. We discovered that several components of the adherens junction complex modulate α-toxin cytotoxicity. By eliminating expression of the junctional protein plekstrin-homology domain containing protein 7 (PLEKHA7), cells gained the ability to recover from α-toxin injury and mice lacking PLEKHA7 exhibited improved healing from
S. aureus
skin infection and enhanced survival of pneumonia. Our data suggest that targeting nonessential host epithelial junction components can reduce
S. aureus
morbidity by enhancing cellular resilience to α-toxin injury.
Effects of Spatial Extent on Modeled Relations between Habitat and Anadromous Salmonid Spawning Success
Authors: Railsback Steven F. , Harvey Bret C. , White Jason L.
Published: October 2015

We address the question of spatial extent: how model results depend on the amount and type of space represented. For models of how stream habitat affects fish populations, how do the amount and characteristics of habitat represented in the model affect its results and how well do those results represent the whole stream? Our analysis used inSalmo, an individual‐based model of anadromous salmonid spawning, incubation, and juvenile rearing. The model was applied to 12 sites, totaling 4.0 km in length, on Clear Creek, California, treating the simulated 4.0 km as a synthetic whole stream. Simulation experiments examined responses of anadromous salmonid spawning and rearing success to habitat variables, such as flow and temperature, when the model included each individual site, all sites, and random combinations of two to nine sites. Some responses, such as temperature effects on egg incubation, were insensitive to spatial extent. Other responses, including the effects of flow on the production of large juveniles, varied sharply among sites and varied with spatial extent. Most small sites had little effect on overall results, but one small site provided exceptionally good juvenile rearing habitat and strongly affected the responses of the entire stream. Larger sites (length > 15 channel widths) in distinct habitat types (e.g., highly disturbed and recently restored) also had strong effects. Including more or longer sites generally increased model representativeness but not consistently. Results highly representative of the entire stream could also be obtained by combining large sites in typical habitat with “hot spots” of especially productive habitat. Finally, sites lower in the watershed appear to be more important to model results and anadromous salmonid spawning success because more juveniles migrate through them.
THE GALAXY UV LUMINOSITY FUNCTION BEFORE THE EPOCH OF REIONIZATION
Authors: Mason Charlotte A. , Trenti Michele , Treu Tommaso
Published: October 2015

We present a model for the evolution of the galaxy ultraviolet (UV) luminosity function (LF) across cosmic time where star formation is linked to the assembly of dark matter halos under the assumption of a mass-dependent, but redshift-independent, efficiency. We introduce a new self-consistent treatment of the halo star formation history, which allows us to make predictions at z > 10 (lookback time ≲500 Myr), when growth is rapid. With a calibration at a single redshift to set the stellar-to-halo mass ratio, and no further degrees of freedom, our model captures the evolution of the UV LF over all available observations (0 ≲ z ≲ 10). The significant drop in luminosity density of currently detectable galaxies beyond z ∼ 8 is explained by a shift of star formation toward less massive, fainter galaxies. Assuming that star formation proceeds down to atomic cooling halos, we derive a reionization optical depth

fully consistent with the latest Planck measurement, implying that the universe is fully reionized at

In addition, our model naturally produces smoothly rising star formation histories for galaxies with L ≲ L
* in agreement with observations and hydrodynamical simulations. Before the epoch of reionization at z > 10 we predict the LF to remain well-described by a Schechter function, but with an increasingly steep faint-end slope (α ∼ −3.5 at z ∼ 16). Finally, we construct forecasts for surveys with James Webb Space Telescope (JWST) and Wide-field Infrared Survey Telescope (WFIRST) and predict that galaxies out to z ∼ 14 will be observed. Galaxies at z > 15 will likely be accessible to JWST and WFIRST only through the assistance of strong lensing magnification.
Update of the BIPM comparison BIPM.RI(II)-K1.Sr-85 of activity measurements of the radionuclide 85Sr to include the 2009 result of the POLATOM (Poland)
Authors: Michotte C , Ratel G , Courte S , Dziel T , Listkowska A
Published: October 2015

Since 1975, ten laboratories have submitted 27 samples of known activity of 85Sr to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.Sr-85. The values of the activity submitted were between about 0.2 MBq and 19 MBq. The key comparison reference value (KCRV) has been recalculated to include the primary standardization result for the POLATOM, Poland. There are now four results in the BIPM.RI(II)-K1.Sr-85 comparison. The degrees of equivalence between each equivalent activity measured in the SIR and the updated KCRV have been calculated and the results are given in the form of a table. A graphical presentation is also given.

Main text

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.

The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
The α-arrestin ARRDC3 mediates ALIX ubiquitination and G protein–coupled receptor lysosomal sorting
Authors: Dores Michael R. , Lin Huilan , Grimsey Neil J. , Mendez Francisco , Trejo JoAnn
Published: October 2015

The sorting of G protein–coupled receptors (GPCRs) to lysosomes is critical for proper signaling and cellular responses. We previously showed that the adaptor protein ALIX regulates lysosomal degradation of protease-activated receptor-1 (PAR1), a GPCR for thrombin, independent of ubiquitin-binding ESCRTs and receptor ubiquitination. However, the mechanisms that regulate ALIX function during PAR1 lysosomal sorting are not known. Here we show that the mammalian α-arrestin arrestin domain–containing protein-3 (ARRDC3) regulates ALIX function in GPCR sorting via ubiquitination. ARRDC3 colocalizes with ALIX and is required for PAR1 sorting at late endosomes and degradation. Depletion of ARRDC3 by small interfering RNA disrupts ALIX interaction with activated PAR1 and the CHMP4B ESCRT-III subunit, suggesting that ARRDC3 regulates ALIX activity. We found that ARRDC3 is required for ALIX ubiquitination induced by activation of PAR1. A screen of nine mammalian NEDD4-family E3 ubiquitin ligases revealed a critical role for WWP2. WWP2 interacts with ARRDC3 and not ALIX. Depletion of WWP2 inhibited ALIX ubiquitination and blocked ALIX interaction with activated PAR1 and CHMP4B. These findings demonstrate a new role for the α-arrestin ARRDC3 and the E3 ubiquitin ligase WWP2 in regulation of ALIX ubiquitination and lysosomal sorting of GPCRs.
Oligomerization and endocytosis of Hedgehog is necessary for its efficient exovesicular secretion
Authors: Parchure Anup , Vyas Neha , Ferguson Charles , Parton Robert G. , Mayor Satyajit
Published: October 2015

Hedgehog (Hh) is a secreted morphogen involved in both short- and long-range signaling necessary for tissue patterning during development. It is unclear how this dually lipidated protein is transported over a long range in the aqueous milieu of interstitial spaces. We previously showed that the long-range signaling of Hh requires its oligomerization. Here we show that Hh is secreted in the form of exovesicles. These are derived by the endocytic delivery of cell surface Hh to multivesicular bodies (MVBs) via an endosomal sorting complex required for transport (ECSRT)–dependent process. Perturbations of ESCRT proteins have a selective effect on long-range Hh signaling in Drosophila wing imaginal discs. Of importance, oligomerization-defective Hh is inefficiently incorporated into exovesicles due to its poor endocytic delivery to MVBs. These results provide evidence that nanoscale organization of Hh regulates the secretion of Hh on ESCRT-derived exovesicles, which in turn act as a vehicle for long-range signaling.
The Task of Hope in Kierkegaard
Authors: Bernier Mark
Published: October 2015

The role and importance of hope in Kierkegaard’s work has received almost no attention. One typically sees hope mentioned only in passing, related to central Kierkegaardian themes—as a mere description of faith, or as a way to illustrate what is lost in certain forms of despair. Rarely does one see hope discussed on its own terms, as having its own place in Kierkegaard’s thought. This is a significant oversight. What this study explores is the place of hope in some of Kierkegaard’s most important themes: despair, faith, and the self. It is shown that these core elements are connected through an essential thread of hope. There are three principal claims of the study. First, while despair involves the absence of hope, a rejection of oneself, and a turn away from one’s relation to God, despair is fundamentally an unwillingness to hope. Second, hope is not simply an ancillary activity of the self; rather, the task of becoming a self is essentially constituted by hope. Thus, when in despair one is unwilling to hope, one is in fact rejecting one’s task of becoming a self. Third, faith stands in opposition to despair precisely because it is a willingness to hope. An essential role of faith is to secure the ground for hope, and in this way faith secures the ground for the self. In short, authentic hope is not merely a fringe element, but is essential to Kierkegaard’s project of the self.
On Despair
Authors: Bernier Mark
Published: October 2015

In this chapter the sickness of despair is discussed, which Kierkegaard explains primarily in two ways: as a structural problem, and a relation. As a structural problem, despair is understood in terms of the self’s inability to manage the synthesis. When the self grasps one factor of the synthesis, the other factor is left unfulfilled. In this sense, despair is a reaction to the inability to achieve a unified identity; something is always lacking. Second, despair as a relation is explained in terms of the self’s consciousness of being in despair—the greater one’s consciousness of oneself, the greater one’s despair. The underlying problem is that we can never rid ourselves of what we are, and we can never truly become what we want to be. Finally, despair can also be understood in terms of the task: despair involves the refusal to take up the task of becoming a self.
Despair and Hope
Authors: Bernier Mark
Published: October 2015

Kierkegaard characterizes the relation between despair and hope in two ways: as hopelessness, and as an unwillingness to hope. Using Aquinas’ account of hope and despair, Kierkegaardian despair may be seen fundamentally as hopelessness (as Michael Theunissen claims). However, when despair is seen in this way, a problem may emerge: only weakness would count as genuine despair, with defiance reduced to a preliminary stage. Such a result could even threaten Kierkegaard’s larger narrative: that despair involves the loss of meaning for the self, with faith positioned as the only solution. This narrative requires that both weakness and defiance be genuine forms of despair. Against this conclusion, the argument is made that despair is better characterized as fundamentally an unwillingness to hope. This secures defiance as a form of despair, and explains the most basic opposition between despair and hope.
TANK-binding kinase 1-dependent or -independent signaling elicits the cell-type-specific innate immune responses induced by the adenovirus vector
Authors: Tsuzuki Sayaka , Tachibana Masashi , Hemmi Masahisa , Yamaguchi Tomoko , Shoji Masaki , Sakurai Fuminori , Kobiyama Kouji , Kawabata Kenji , Ishii Ken J. , Akira Shizuo , Mizuguchi Hiroyuki
Published: October 2015

Adenovirus vectors (Adv) elicit innate immune responses via several pattern-recognition receptors. Although it has been suggested that various Adv-induced mechanisms play important roles in the induction of innate immunity in vitro , the impacts of these mechanisms in vivo remain unclear. Viral nucleic acids elicit innate immune responses through the recognition of cytosolic nucleic acid sensors and transduce intracellular signals to TANK-binding kinase (TBK) 1. In this study, to determine the impacts of viral nucleic acids on innate immune responses in vivo , we administered transgene-expressing Adv to Tbk1 -deficient mice. The systemic Adv administration failed to induce type I interferons (type I IFNs) in the spleen, but not the liver, of Tbk1 -deficient mice, resulting in the increase of transgene-expressing cells in the spleen, but not the liver. Moreover, Adv failed to induce type I IFNs in the bone-marrow-derived dendritic cells, but not the mouse embryonic fibroblasts, from Tbk1 -deficient mice in vitro . These results support the idea that Adv elicit innate immunity in immune cells and non-immune cells in a TBK1-dependent and TBK1-independent manner, respectively.
Bacterial Wilt of Dry-Edible Beans in the Central High Plains of the U.S.: Past, Present, and Future
Authors: Harveson Robert M. , Schwartz Howard F. , Urrea Carlos A. , Yonts C. Dean
Published: October 2015

Bacterial wilt, caused by Curtobacterium flaccumfaciens pv. flaccumfaciens, was first recognized and described as a new dry bean disease near Redfield, SD after the 1921 growing season on the farm of the Office of Forage Investigations. Between the late 1930s and the early 1950s it became one of the more problematic bacterial diseases of dry beans. It became an endemic problem in dry bean production throughout western Nebraska and other areas of the central high plains during the 1960s and early 1970s. By the early 1980s, the disease had virtually disappeared with the implementation of cultural practices. The disease was rediscovered in two fields in Nebraska late in the 2003 season. It was assumed to be an isolated incident. However, the next season the pathogen was widespread throughout western Nebraska production fields. Our research suggests that the return of bean wilt throughout the central high plains over the last decade is not due to a single factor but a combination of new changes in cultural practices, environmental stresses, and unfamiliarity with the pathogen and its past history.
Anticonvulsants or Antidepressants in Combination Pharmacotherapy for Treatment of Neuropathic Pain in Cancer Patients
Authors: Guan Jia , Tanaka Shiro , Kawakami Koji
Published: October 2015

Objective:

To investigate the efficacy of anticonvulsants or antidepressants in combination pharmacotherapy for treatment of neuropathic pain in cancer patients.

Materials and Methods:

We systematically searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and the metaRegister of Controlled Trials for randomized controlled trials that compared anticonvulsants or antidepressants in combination pharmacotherapy (experimental group) with treatments without anticonvulsants or antidepressants (control group) for neuropathic pain in cancer patients. Risk of bias was evaluated in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. The primary outcome was a mean difference (MD) in change in global pain analyzed by a random-effects model.

Results:

Eight trials met the inclusion criteria with a total of 1359 participants of whom 698 received an experimental intervention. The MD in change in global pain suggested a favorable association with anticonvulsants or antidepressants in combination pharmacotherapy compared with control groups (MD, −0.41; 95% confidence interval, −0.70 to −0.12) with no heterogeneity across trials (I
2=0%). The MD in change estimated in all sensitivity analyses ranged from −0.36 to −0.47, suggesting that these effects were consistent across different study designs and statistical assumptions.

Conclusions:

Anticonvulsants or antidepressants in combination pharmacotherapy reduce neuropathic pain in cancer patients compared with treatments without anticonvulsants or antidepressants. Limited evidence precludes a recommendation on specific adjuvants in combination pharmacotherapy.
Differential Efficacy of Ketamine in the Acute versus Chronic Stages of Complex Regional Pain Syndrome in Mice
Authors: Tajerian Maral , Leu David , Yang Phillip , Huang Ting Ting , Kingery Wade S. , Clark J. David
Published: October 2015

AbstractAbstract

By using a mouse model of complex regional pain syndrome, short-term systemic administration of ketamine reversed mechanical allodynia when administered in the chronic, not acute, phase. The sustained behavioral effects of ketamine correlated with reduced changes in astrocyte activation and pain-related effectors in the spinal cord, identifying potential therapeutic targets.

Background

Complex regional pain syndrome (CRPS) is a painful, disabling, and often chronic condition, where many patients transition from an acute phase with prominent peripheral neurogenic inflammation to a chronic phase with evident central nervous system changes. Ketamine is a centrally acting agent believed to work through blockade of N-methyl-d- aspartate receptors and is being increasingly used for the treatment of refractory CRPS, although the basis for the drug’s effects and efficacy at different stages of the syndrome remains unclear.

Methods

The authors used a mouse model of CRPS (n = 8 to 12/group) involving tibia fracture/cast immobilization to test the efficacy of ketamine (2 mg kg−1 day−1; 7 days) or vehicle infusion during acute (3 weeks after fracture) and chronic (7 weeks after fracture) stages.

Results

Acute-phase fracture mice displayed increased limb temperature, edema, and nociceptive sensitization that were not reduced by ketamine. Fracture mice treated with ketamine during the chronic phase showed reduced nociceptive sensitization that persisted beyond completion of the infusion. During this chronic phase, ketamine also reduced latent nociceptive sensitization and improved motor function at 18 weeks after fracture. No side effects of the infusions were identified. These behavioral changes were associated with altered spinal astrocyte activation and expression of pain-related proteins including N-methyl-d-aspartate receptor 2b, Ca2+/calmodulin-dependent protein kinase II, and brain-derived neurotrophic factor.

Conclusions

Collectively, these results demonstrate that ketamine is efficacious in the chronic, but not acute, stage of CRPS, suggesting that the centrally acting drug is relatively ineffective in early CRPS when peripheral mechanisms are more critical for supporting nociceptive sensitization.
Minor Postoperative Increases of Creatinine Are Associated with Higher Mortality and Longer Hospital Length of Stay in Surgical Patients
Authors: Kork Felix , Balzer Felix , Spies Claudia D. , Wernecke Klaus-Dieter , Ginde Adit A. , Jankowski Joachim , Eltzschig Holger K.
Published: October 2015

AbstractAbstract

Even minor creatinine increases not meeting acute kidney injury criteria were associated with an increased risk of death and hospital length of stay, and this risk was more pronounced in noncardiac compared with cardiac surgical patients.

Supplemental Digital Content is available in the text.

Background

Surgical patients frequently experience postoperative increases in creatinine levels. The authors hypothesized that even small increases in postoperative creatinine levels are associated with adverse outcomes.

Methods

The authors examined the association of postoperative changes from preoperative baseline creatinine with all-cause in-hospital mortality and hospital length of stay (HLOS) in a retrospective analysis of surgical patients at a single tertiary care center between January 2006 and June 2012.

Results

The data of 39,369 surgical patients (noncardiac surgery n = 37,345; cardiac surgery n = 2,024) were analyzed. Acute kidney injury (AKI)—by definition of the Kidney Disease: Improving Global Outcome group—was associated with a five-fold higher mortality (odds ratio [OR], 4.8; 95% CI, 4.1 to 5.7; P < 0.001) and a longer HLOS of 5 days (P < 0.001) after adjusting for age, sex, comorbidities, congestive heart failure, preoperative hemoglobin, preoperative creatinine, exposure to radiocontrast agent, type of surgery, and surgical AKI risk factors. Importantly, even minor creatinine increases (Δcreatinine 25 to 49% above baseline but < 0.3 mg/dl) not meeting AKI criteria were associated with a two-fold increased risk of death (OR, 1.7; 95% CI, 1.3 to 2.4; P < 0.001) and 2 days longer HLOS (P < 0.001). This was more pronounced in noncardiac surgery patients. Patients with minor creatinine increases had a five-fold risk of death (OR, 5.4; 95% CI, 1.5 to 20.3; P < 0.05) and a 3-day longer HLOS (P < 0.01) when undergoing noncardiac surgery.

Conclusions

Even minor postoperative increases in creatinine levels are associated with adverse outcomes. These results emphasize the importance to find effective therapeutic approaches to prevent or treat even mild forms of postoperative kidney dysfunction to improve surgical outcomes.
Two Techniques for Retrograde Flexible Intramedullary Fixation of Pediatric Femur Fractures: All-Lateral Entry Versus Medial and Lateral Entry Point
Authors: Cage Jason M. , Black Sheena R. , Wimberly Robert L. , Cook Jay B. , Gheen William T. , Jo ChanHee , Riccio Anthony I.
Published: October 2015

Background:

Multiple techniques for flexible intramedullary nailing (FIMN) of pediatric femur fractures have been described. To our knowledge, no study has compared combined medial-lateral (ML) entry versus all-lateral (AL) entry retrograde nailing. This study compares surgical outcomes, radiographic outcomes, and complication rates between these 2 techniques.

Methods:

A retrospective review of a consecutive series of patients treated by retrograde, dual FIMN of femur fractures was performed from 2005 to 2012. Demographics and operative data were recorded. Radiographs were analyzed for fracture pattern, fracture location, percent canal fill by the nails, as well as shortening and angulation at the time of osseous union. Rates of symptomatic implants and their removal were noted. Data were compared between patients treated with medial and lateral entry (ML group) nailing and those treated with all-lateral entry (AL group) nailing using the Student t test and correlation statistics.

Results:

Of the 244 children with femoral shaft fractures treated with retrograde FIMN using Ender stainless steel nails, 156 were in the ML group and 88 were in the AL group. There were no statistical differences in sex (74% vs. 82% males), age (8.0 vs. 8.6 y), weight (29.4 vs. 31.1 kg), or fracture pattern between the 2 groups. The average total anesthesia time was less in the AL group (133 vs. 103 min) (P<0.0001). There was no difference between the techniques in shortening (3.9 vs. 3.0 mm), coronal angulation (2.9 vs. 2.6 degrees), or sagittal angulation (3.3 vs. 2.7 degrees) at union. In the AL group, there was a correlation between canal fill and reduced shortening at union. No differences were found in the presence or degree of varus alignment, procurvatum deformity, or recurvatum angulation between the constructs. There were 5 malunions in the AL group and 9 malunions in the ML group (5.7% vs. 5.8%, P=1). The incidence of having a healed femur fracture with >10 degrees of valgus was higher in the AL group (0% vs. 3.4%) (P=0.04). There were no differences between the groups in the rate of symptomatic implant removal or surgical complications.

Conclusions:

The AL entry technique for FIMN of pediatric femur fractures is 30 minutes faster without worse final fracture alignment, additional complications, or increased rates of symptomatic implants. When using the AL technique, specific attention should be paid to percentage of canal fill and ensuring that the fracture is not reduced in a valgus position.

Level of Evidence:

Level III—therapeutic.
Ultrasound Examination for Infants Born Breech by Elective Cesarean Section With a Normal Hip Exam for Instability
Authors: Pacana Matthew J. , Hennrikus William L. , Slough Jennifer , Curtin William
Published: October 2015

Introduction:

Because of the risk of developmental dysplasia of the hip in infants born breech—despite a normal physical exam—the American Academy of Pediatrics (AAP) guidelines recommend ultrasound (US) hip imaging at 6 weeks of age for breech females and optional imaging for breech males. The purpose of this study is to report US results and follow-up of infants born breech with a normal physical exam.

Methods:

The electronic medical record for children born at 1 hospital from 2008 to 2011 was reviewed. Data were analyzed for sex, birth weight, breech position, birth order, ethnicity, US and x-ray results, follow-up, and cost.

Results:

A total of 237 infants were born breech with a normal physical examination, all delivered by cesarean section. Of the infants, 55% were male and 45% female. About 151 breech infants (64%) with a normal Barlow and Ortolani exam had a precautionary hip US as recommended by the AAP performed at an average of 7 weeks of age. Eighty-six breech infants (35%) did not have an US and were followed clinically. Of the 151 infants that had an US, 140 (93%) were read as normal. None had a dislocated hip. Two patients had a normal physical exam but laxity on US. These 2 patients were the only infants treated in a Pavlik harness. A pediatric orthopaedic surgeon followed those with subtle US findings and no laxity until normal.

Conclusions:

The decision by the AAP to recommend US screening at 6 weeks of age for infants with a normal physical exam but breech position was based on an extensive literature review and expert opinion. Not all pediatricians are following the AAP guidelines. The decision to perform an US should be done on a case-by-case basis by the examining physician. A more practical, cost-effective strategy would be to skip the US if the physical exam is normal and simply obtain an AP pelvis x-ray at 4 months.

Level of Evidence:

Level III—this is a case-control study investigating the outcomes of infants on data drawn from the electronic medical record.
Long-term Outcome of External Tibial Derotation Osteotomies in Children With Cerebral Palsy
Authors: Er Mehmet S. , Bayhan Ilhan A. , Rogers Kenneth J. , Abousamra Oussama , Church Chris , Henley John , Miller Freeman
Published: October 2015

Background:

Internal tibial torsion (ITT) is a common boney deformity in children with cerebral palsy (CP). The current recommended treatment is tibial derotation osteotomy (TDO) to improve gait biomechanics. Satisfactory short-term results after TDO have been reported but long-term results have not been studied. The purpose of this study was to evaluate the long-term outcome after external TDO performed to correct ITT in ambulatory children with CP.

Methods:

Following IRB approval, gait kinematics and passive range of motion measurements were retrospectively evaluated in children with spastic CP who underwent TDO due to ITT comparing preoperative (E0), short-term postoperative (E1; 1 to 3 y post), and long-term postoperative (E2; >5 y post) results. Limbs were categorized as corrected, undercorrected, or overcorrected at both E1 and E2, by comparing the subjects mean tibial rotation (MTR) in gait to a group of typically developing children. Age at surgery, preop MTR (at E0), preop gait velocity (at E0), gross motor function classification system score, and foot deformity were evaluated to determine their influence on long-term results.

Results:

The study sample consisted of 36 legs (with E0 and E2) and 17 legs (with E0, E1, and E2). The mean age at surgery was 7.4±2.8 (range, 4 to 16.6) years. Comparing the changes over time, kinematic MTR improved from 17±11 degrees initially (E0) to −10±14 degrees short term (E1) and progressed to −23±13 degrees long term (E2) (P<0.05 E0/E1/E2; internal rotation is positive). At E2, 16 legs (44%) were found to be in the kinematic corrected group and 20 legs (56%) in the kinematic overcorrected group. There were no significant differences between the corrected and overcorrected groups of children in respect to age of surgery, gross motor function classification system, E0 MTR, gait velocity, or foot deformity.

Conclusions:

Although external TDO is an accepted form of treatment in children with CP, in the long term a tendency to move into external tibial torsion is common. Therefore, caution is warranted with children who initially present with ITT to avoid overcorrection.

Level of Evidence:

Level IV—therapeutic study.
Preoperative Computer Simulation and Patient-specific Guides are Safe and Effective to Correct Forearm Deformity in Children
Authors: Bauer Andrea S. , Storelli Dora A. R. , Sibbel Sarah E. , McCarroll H. Relton , Lattanza Lisa L.
Published: October 2015

Background:

Posttraumatic and congenital forearm deformities in children can be difficult to appreciate in all planes. In cases of distal radioulnar joint instability and loss of forearm rotation, surgical correction is challenging. Advances in 3-dimensional printing allow creation of custom guides at a reasonable cost, enabling precise correction of the deformity in all planes.

Methods:

Nineteen children with deformity of the forearm had corrective osteotomies performed using preoperative 3-dimensional computer modeling and patient-specific surgical guides. Surgicase software was used for 3-dimensional planning of the corrective osteotomy, by superimposing a mirror image of the unaffected side as a template. Based upon this planning, patient-specific surgical guides were manufactured. Radiographic and clinical outcomes were assessed.

Results:

Three patients had a diagnosis of multiple hereditary exostoses, and one of Madelung’s deformity. The remaining 15 patients had a diagnosis of fracture malunion. Average preoperative angulation of both the radius and ulna was 23 degrees. For the patients with fracture malunions, the time from injury to surgery ranged from 6 months to 8 years. Twelve patients underwent osteotomies of both the radius and ulna, 5 had osteotomies of the radius alone, and 2 had a single osteotomy of the ulna only. All osteotomies went on to unite and no patient lost range of motion. Preoperative arc of forearm rotation averaged 101 degrees (range 0 to 180 degrees). Postoperatively, this improved to 133 degrees (range 85 to 180 degrees). Eight patients had distal radioulnar instability preoperatively, all of which normalized after surgery. There were 4 complications: 1 hypertrophic scar, 1 subject with extensor pollicis longus weakness, and 2 transient sensory losses in the superficial radial nerve distribution.

Conclusions:

This case series demonstrates that 3-dimensional computer modeling permits complex and multiple osteotomies to be done safely to achieve deformity correction in children. Limitations in forearm rotation and distal radioulnar malalignment can be reliably improved using this technique.

Level of Evidence:

Level IV—retrospective case series.
Predictors of Recurrent Patellar Instability in Children and Adolescents After First-time Dislocation
Authors: Jaquith Bradley P. , Parikh Shital N.
Published: October 2015

Background:

Patellar dislocations are one of the most common knee injuries in children and adolescents and are challenging to treat. Recurrence rates are relatively high and many patients have functional limitations, even in the absence of a recurrent instability episode. The purpose of this study was to examine the risk factors in patients with first-time patellofemoral dislocations to develop a prediction model of recurrence.

Methods:

A single institution retrospective review of all patients with a first-time patellofemoral dislocation from 2002 to 2013 was performed. Demographic risk factors (age, sex, laterality, mechanism of injury, and history of contralateral patellar dislocation) and radiographic risk factors (increased patella height, trochlear dysplasia, and skeletal immaturity) were examined. Patella height was measured using Caton-Deschamps index (CDI). Trochlear dysplasia was assessed using the 2-grade Dejour classification and skeletal immaturity was assessed based on the distal femur and proximal tibia physis (open, closing, or closed).

Results:

In total, 266 knees in 250 patients were included in the study. Of these, 222 (83.5%) were treated nonoperatively and 44 (16.5%) were treated surgically. Of the knees treated nonoperatively, 77 (34.7%) had a recurrence. Significant risk factors for recurrence on univariate analysis were age 14 years and below, history of contralateral patellar dislocation, trochlear dysplasia, skeletal immaturity, and a CDI>1.45. Multivariate analysis was performed and trochlear dysplasia and skeletal immaturity were the most significant factors with odds ratios of 3.56 and 2.23, respectively. The presence of all 4 multivariate risk factors (CDI>1.45, history of contralateral patellar dislocation, trochlear dysplasia, and skeletal immaturity) had a predicted risk of recurrence of 88%. The presence of any 3 risk factors had a predicted risk of about 75% and the presence of any 2 risk factors had a predicted risk of about 55%.

Conclusions:

Trochlear dysplasia, skeletal immaturity, CDI>1.45, and a history of contralateral patellar dislocation were all significant risk factors for recurrence in patients with first-time patellar dislocations. A predictive model for calculation of recurrence risk was developed for any combination of the different risk factors. This information is useful when counseling patients and their families after first-time patellar dislocation about prognosis and potential outcomes.

Level of Evidence:

Level IV—retrospective case series.
Comparison of the Clinical Effectiveness of PFNA, PFLCP, and DHS in Treatment of Unstable Intertrochanteric Femoral Fracture
Authors: Huang Shou-Guo , Chen Bo , Zhang Yong , Nie Feng-Feng , Ju Liang , Li Ming , Zhang Ying-Hua
Published: October 2015

In this study, a randomized trial was conducted to compare the clinical effectiveness of proximal femoral locking compression plate (PFLCP), dynamic hip screw (DHS), and proximal femoral nail antirotation (PFNA) for unstable intertrochanteric femoral fracture treatment. Ninety patients diagnosed with unstable intertrochanteric femoral fracture were enrolled in this study at the department of orthopedics at Linyi Second People's Hospital between May 2010 and May 2012. Fractures were classified according to Tronzo–Evans classification, and the patients were randomly divided into 3 groups, PFLCP, DHS, and PFNA, with 30 patients in each group. The length of incision, operative time, intraoperative blood loss, postoperative drainage, postoperative weight-bearing ambulation time, and duration of fracture union were significantly lower in patients who underwent PFNA and PFLCP compared to patients treated with DHS. Furthermore, when the same clinical parameters were used for comparison, the PFNA group showed markedly lower values compared with the PFLCP group. The total incidence of postoperative complications was significantly different among the PFNA, PFLCP, and DHS groups, with the PFNA group exhibiting markedly lower complication rates compared with PFLCP and DHS groups. However, PFLCP and DHS groups did not show significant differences in the incidence of postoperative complications. Notably, the Harris hip score of PFNA group was markedly higher than the DHS group. In conclusion, our results provide convincing evidence that PFNA may be the most effective internal fixation treatment of unstable intertrochanteric femoral fracture.
Primate archaeology reveals cultural transmission in wild chimpanzees (Pan troglodytes verus)
Authors: Luncz Lydia V. , Wittig Roman M. , Boesch Christophe
Published: October 2015

Recovering evidence of past human activities enables us to recreate behaviour where direct observations are missing. Here, we apply archaeological methods to further investigate cultural transmission processes in percussive tool use among neighbouring chimpanzee communities in the Taï National Park, Côte d'Ivoire, West Africa. Differences in the selection of nut-cracking tools between neighbouring groups are maintained over time, despite frequent female transfer, which leads to persistent cultural diversity between chimpanzee groups. Through the recovery of used tools in the suggested natal territory of immigrants, we have been able to reconstruct the tool material selection of females prior to migration. In combination with direct observations of tool selection of local residents and immigrants after migration, we uncovered temporal changes in tool selection for immigrating females. After controlling for ecological differences between territories of immigrants and residents our data suggest that immigrants abandoned their previous tool preference and adopted the pattern of their new community, despite previous personal proficiency of the same foraging task. Our study adds to the growing body of knowledge on the importance of conformist tendencies in animals.