bluuebunny/crossref_metadata_2025 huggingface dataset:
Does plugging unused combination screw holes improve the fatigue life of fixation with locking plates in comminuted supracondylar fractures of the femur?
Authors: Firoozabadi R. , McDonald E. , Nguyen T-Q. , Buckley J. M. , Kandemir U.
Published: February 2012

Filling the empty holes in peri-articular locking plates may improve the fatigue strength of the fixation. The purpose of this in vitro study was to investigate the effect of plugging the unused holes on the fatigue life of peri-articular distal femoral plates used to fix a comminuted supracondylar fracture model.

A locking/compression plate was applied to 33 synthetic femurs and then a 6 cm metaphyseal defect was created (AO Type 33-A3). The specimens were then divided into three groups: unplugged, plugged with locking screw only and fully plugged holes. They were then tested using a stepwise or run-out fatigue protocol, each applying cyclic physiological multiaxial loads.

All specimens in the stepwise group failed at the 770 N load level. The mean number of cycles to failure for the stepwise specimen was 25 500 cycles (sd 1500), 28 800 cycles (sd 6300), and 26 400 cycles (sd 2300) cycles for the unplugged, screw only and fully plugged configurations, respectively (p = 0.16). The mean number of cycles to failure for the run-out specimens was 42 800 cycles (sd 10 700), 36 000 cycles (sd 7200), and 36 600 cycles (sd 10 000) for the unplugged, screw only and fully plugged configurations, respectively (p = 0.50). There were also no differences in axial or torsional stiffness between the constructs. The failures were through the screw holes at the level of comminution.

In conclusion, filling the empty combination locking/compression holes in peri-articular distal femur locking plates at the level of supracondylar comminution does not increase the fatigue life of the fixation in a comminuted supracondylar femoral fracture model (AO 33-A3) with a 6 cm gap.
A prospective study comparing the functional outcome of computer-assisted and conventional total knee replacement
Authors: Hoffart H-E. , Langenstein E. , Vasak N.
Published: February 2012

The aim of this prospective single-centre study was to assess the difference in clinical outcome between total knee replacement (TKR) using computerised navigation and that of conventional TKR. We hypothesised that navigation would give a better result at every stage within the first five years. A total of 195 patients (195 knees) with a mean age of 70.0 years (39 to 89) were allocated alternately into two treatment groups, which used either conventional instrumentation (group A, 97 knees) or a navigation system (group B, 98 knees). After five years, complete clinical scores were available for 121 patients (62%). A total of 18 patients were lost to follow-up. Compared with conventional surgery, navigated TKR resulted in a better mean Knee Society score (p = 0.008). The difference in mean Knee Society scores over time between the two groups was not constant (p = 0.006), which suggests that these groups differed in their response to surgery with time. No significant difference in the frequency of malalignment was seen between the two groups.

In summary, computerised navigation resulted in a better functional outcome at five years than conventional techniques. Given the similarity in mechanical alignment between the two groups, rotational alignment may prove to be a better method of identifying differences in clinical outcome after navigated surgery.
Incidence of venous thromboembolism in elective foot and ankle surgery with and without aspirin prophylaxis
Authors: Griffiths J. T. , Matthews L. , Pearce C. J. , Calder J. D. F.
Published: February 2012

The incidence of deep-vein thrombosis (DVT) and pulmonary embolism (PE) is thought to be low following foot and ankle surgery, but the routine use of chemoprophylaxis remains controversial. This retrospective study assessed the incidence of symptomatic venous thromboembolic (VTE) complications following a consecutive series of 2654 patients undergoing elective foot and ankle surgery. A total of 1078 patients received 75 mg aspirin as routine thromboprophylaxis between 2003 and 2006 and 1576 patients received no form of chemical thromboprophylaxis between 2007 and 2010. The overall incidence of VTE was 0.42% (DVT, 0.27%; PE, 0.15%) with 27 patients lost to follow-up. If these were included to create a worst case scenario, the overall VTE rate was 1.43%. There was no apparent protective effect against VTE by using aspirin.

We conclude that the incidence of VTE following foot and ankle surgery is very low and routine use of chemoprophylaxis does not appear necessary for patients who are not in the high risk group for VTE.
Groin pain after replacement of the hip
Authors: Henderson R. A. , Lachiewicz P. F.
Published: February 2012

Persistent groin pain after seemingly successful total hip replacement (THR) appears to have become more common. Recent studies have indicated a high incidence after metal-on-polyethylene and metal-on-metal conventional THR and it has been documented in up to 18% of patients after metal-on-metal resurfacing. There are many causes, including acetabular loosening, stress fracture, and iliopsoas tendonitis and impingement. The evaluation of this problem requires a careful history and examination, plain radiographs and an algorithmic approach to special diagnostic imaging and tests. Non-operative treatment is not usually successful. Specific operative treatment depending on the cause of the pain usually involves revision of the acetabular component, iliopsoas tenotomy or other procedures, and is usually successful. Here, an appropriate algorithm is described.
The relationship between microbiology results in the second of a two-stage exchange procedure using cement spacers and the outcome after revision total joint replacement for infection
Authors: Sorlí L. , Puig L. , Torres-Claramunt R. , González A. , Alier A. , Knobel H. , Salvadó M. , Horcajada J. P.
Published: February 2012

Patients with infected arthroplasties are normally treated with a two-stage exchange procedure using polymethylmethacrylate bone cement spacers impregnated with antibiotics. However, spacers may act as a foreign body to which micro-organisms may adhere and grow. In this study it was hypothesised that subclinical infection may be diagnosed with sonication of the surface biofilm of the spacer. The aims were to assess the presence of subclinical infection through sonication of the spacer at the time of a second-stage procedure, and to determine the relationship between subclinical infection and the clinical outcome. Of 55 patients studied, 11 (20%) were diagnosed with subclinical infection. At a mean follow-up of 12 months (interquartile range 6 to 18), clinical failure was found in 18 (32.7%) patients. Of the patients previously diagnosed with subclinical infection, 63% (7 of 11) had failed compared with 25% (11 of 44) of those without subclinical infection (odds ratio 5.25, 95% confidence interval 1.29 to 21.4, p = 0.021). Sonication of the biofilm of the surface of the spacer is useful in order to exclude subclinical infection and therefore contributes to improving the outcome after two-stage procedures.
Use of multimodal intra-operative monitoring in averting nerve injury during complex hip surgery
Authors: Sutter M. , Hersche O. , Leunig M. , Guggi T. , Dvorak J. , Eggspuehler A.
Published: February 2012

Peripheral nerve injury is an uncommon but serious complication of hip surgery that can adversely affect the outcome. Several studies have described the use of electromyography and intra-operative sensory evoked potentials for early warning of nerve injury. We assessed the results of multimodal intra-operative monitoring during complex hip surgery. We retrospectively analysed data collected between 2001 and 2010 from 69 patients who underwent complex hip surgery by a single surgeon using multimodal intra-operative monitoring from a total pool of 7894 patients who underwent hip surgery during this period. In 24 (35%) procedures the surgeon was alerted to a possible lesion to the sciatic and/or femoral nerve. Alerts were observed most frequently during peri-acetabular osteotomy. The surgeon adapted his approach based on interpretation of the neurophysiological changes. From 69 monitored surgical procedures, there was only one true positive case of post-operative nerve injury. There were no false positives or false negatives, and the remaining 68 cases were all true negative. The sensitivity for predicting post-operative nerve injury was 100% and the specificity 100%. We conclude that it is possible and appropriate to use this method during complex hip surgery and it is effective for alerting the surgeon to the possibility of nerve injury.
Effective catalysis of poly(ethylene terephthalate) (PET) degradation by metallic acetate ionic liquids
Authors: Zhou Xueyuan , Lu Xingmei , Wang Qian , Zhu Minli , Li Zengxi
Published: February 2012

Poly(ethylene terephthalate) (PET) is widely used for beverage bottles, electrical and electronic instruments, household wares, and so on. As a consequence of dramatically increasing consumption, recycling of post-consumer PET products has become an important environmental opportunity for sustainable usage in society. In this paper, we investigated the use of chlorine-free metallic acetate ionic liquids (ILs) as catalysts for the degradation of PET because of their lower toxicity, corrosivity, and cost. 1,3-Diethylimidazolium triaceticzincate ([deim][Zn(OAc)3]) behaved as the best in this group. The synthesized ILs and the major product, characterized by a variety of techniques and factors affecting glycolysis, were examined. Under optimum conditions, conversion of PET reached 98.05 %, and the selectivity of the bis(hydroxyethyl) terephthalate (BHET) monomer was 70.94 %. A probable mechanism for the glycolysis of PET catalyzed by [deim][Zn(OAc)3] was given. In our opinion, catalysis accounted for the synergic effect of the cation and anion of the IL.
Sleep Problems and Early Developmental Delay: Implications for Early Intervention Programs
Authors: Bonuck Karen , Grant Roy
Published: February 2012

Sleep disorders negatively impact behavior, cognition, and growth—the same areas targeted by early intervention. Conversely, developmental delays and disabilities may themselves precipitate sleep disorders. Young children with developmental delays experience sleep disorders at a higher rate than do typically developing children; the most common types are difficulties initiating or maintaining sleep and sleep disordered breathing. To date, attention has been focused on sleep problems in children with specific conditions (e.g., autism, genetic syndromes, prematurity, and seizure disorder). The authors review evidence of sleep problems' broader impact across the range of children screened for early intervention. Eligibility evaluations for early intervention address the five developmental domains: adaptive, motor, cognitive, communication, and socioemotional. Disordered sleep may be symptomatic of socioemotional and adaptive problems. Assessing sleep problems within the evaluation may help establish eligibility for early intervention services and would maximize developmental potential by ensuring timely identification, referral, and treatment.
Unprofitable Cross-Buying: Evidence from Consumer and Business Markets
Authors: Shah Denish , Kumar V. , Qu Yingge , Chen Sylia
Published: February 2012

Conventional wisdom, marketing literature, and cross-selling practices to date are based on the notion that customer cross-buying is positively associated with customer profitability. However, this study finds that when certain customers with persistent adverse behavioral traits (e.g., limited spending, excessive revenue reversals, excessive service requests, promotion purchase behavior) engage in cross-buying, they exhibit a downward spiral of unprofitable relationship, with the losses increasing with higher levels of cross-buy. The authors analyze the customer databases of five firms and find that 10%–35% of the firms' customers who cross-buy are unprofitable and account for a significant proportion (39%–88%) of the firms' total loss from its customers. Consequently, the authors present a two-stage framework to enable managers to discern customers who are likely to engage in profitable versus unprofitable cross-buying. Overall, the findings refine the basic understanding of the cross-buy phenomenon and motivate managers to rethink their marketing practices and policies, which are typically designed to maximize cross-buy opportunities for every customer.
Functional Analysis of VPS41-Mediated Neuroprotection inCaenorhabditis elegansand Mammalian Models of Parkinson's Disease
Authors: Harrington Adam J. , Yacoubian Talene A. , Slone Sunny R. , Caldwell Kim A. , Caldwell Guy A.
Published: February 2012

Disruption of the lysosomal system has emerged as a key cellular pathway in the neurotoxicity of α-synuclein (α-syn) and the progression of Parkinson's disease (PD). A large-scale RNA interference (RNAi) screen usingCaenorhabditis elegansidentified VPS-41, a multidomain protein involved in lysosomal protein trafficking, as a modifier of α-syn accumulation and dopaminergic neuron degeneration (Hamamichi et al., 2008). Previous studies have shown a conserved neuroprotective function of human VPS41 (hVPS41) against PD-relevant toxins in mammalian cells andC. elegansneurons (Ruan et al., 2010). Here, we report that both the AP-3 (heterotetrameric adaptor protein complex) interaction domain and clathrin heavy-chain repeat domain are required for protectingC. elegansdopaminergic neurons from α-syn-induced neurodegeneration, as well as to prevent α-syn inclusion formation in an H4 human neuroglioma cell model. Using mutantC. elegansand neuron-specific RNAi, we revealed that hVPS41 requires both a functional AP-3 (heterotetrameric adaptor protein complex) and HOPS (homotypic fusion and vacuole protein sorting)-tethering complex to elicit neuroprotection. Interestingly, two nonsynonymous single-nucleotide polymorphisms found within the AP-3 interacting domain of hVPS41 attenuated the neuroprotective property, suggestive of putative susceptibility factors for PD. Furthermore, we observed a decrease in α-syn protein level when hVPS41 was overexpressed in human neuroglioma cells. Thus, the neuroprotective capacity of hVPS41 may be a consequence of enhanced clearance of misfolded and aggregated proteins, including toxic α-syn species. These data reveal the importance of lysosomal trafficking in maintaining cellular homeostasis in the presence of enhanced α-syn expression and toxicity. Our results support hVPS41 as a potential novel therapeutic target for the treatment of synucleinopathies like PD.
A Phox2- and Hand2-DependentHand1 cis-Regulatory Element Reveals a Unique Gene Dosage Requirement forHand2during Sympathetic Neurogenesis
Authors: Vincentz Joshua W. , VanDusen Nathan J. , Fleming Andrew B. , Rubart Michael , Firulli Beth A. , Howard Marthe J. , Firulli Anthony B.
Published: February 2012

Neural crest cell specification and differentiation to a sympathetic neuronal fate serves as an important model for neurogenesis and depends upon the function of both bHLH transcription factors, notably Hand2, and homeodomain transcription factors, including Phox2b. Here, we define a 1007 bpcis-regulatory element 5′ of theHand1gene sufficient to drive reporter expression within the sympathetic chain of transgenic mice. Comparative genomic analyses uncovered evolutionarily conserved consensus-binding sites within this element, which chromatin immunoprecipitation and electrophoretic mobility shift assays confirm are bound by Hand2 and Phox2b. Mutational analyses revealed that the conserved Phox2 and E-box binding sites are necessary for propercis-regulatory element activity, and expression analyses on bothHand2conditionally null and hypomorphic backgrounds demonstrate thatHand2is required for reporter activation in a gene dosage-dependent manner. We demonstrate that Hand2 and Hand1 differentially bind the E-boxes in thiscis-regulatory element, establishing molecular differences between these two factors. Finally, we demonstrate that Hand1 is dispensable for normal tyrosine hydroxylase (TH) and dopamine β-hydroxylase (DBH) expression in sympathetic neurons, even whenHand2gene dosage is concurrently reduced by half. Together, these data define a tissue-specificHand1 cis-regulatory element controlled by two factors essential for the development of the sympathetic nervous system and providein vivoregulatory evidence to support previous findings that Hand2, rather than Hand1, is predominantly responsible for regulating TH, DBH, andHand1expression in developing sympathetic neurons.
When Up Is Down in 0g: How Gravity Sensing Affects the Timing of Interceptive Actions
Authors: Senot Patrice , Zago Myrka , Le Séac'h Anne , Zaoui Mohammed , Berthoz Alain , Lacquaniti Francesco , McIntyre Joseph
Published: February 2012

Humans are known to regulate the timing of interceptive actions by modeling, in a simplified way, Newtonian mechanics. Specifically, when intercepting an approaching ball, humans trigger their movements a bit earlier when the target arrives from above than from below. This bias occurs regardless of the ball's true kinetics, and thus appears to reflect an a priori expectation that a downward moving object will accelerate. We postulate that gravito-inertial information is used to tune visuomotor responses to match the target's most likely acceleration. Here we used the peculiar conditions of parabolic flight—where gravity's effects change every 20 s—to test this hypothesis. We found a striking reversal in the timing of interceptive responses performed in weightlessness compared with trials performed on ground, indicating a role of gravity sensing in the tuning of this response. Parallels between these observations and the properties of otolith receptors suggest that vestibular signals themselves might plausibly provide the critical input. Thus, in addition to its acknowledged importance for postural control, gaze stabilization, and spatial navigation, we propose that detecting the direction of gravity's pull plays a role in coordinating quick reactions intended to intercept a fast-moving visual target.
Reduction of Metabolic Cost during Motor Learning of Arm Reaching Dynamics
Authors: Huang Helen J. , Kram Rodger , Ahmed Alaa A.
Published: February 2012

It is often assumed that the CNS controls movements in a manner that minimizes energetic cost. While empirical evidence for actual metabolic minimization exists in locomotion, actual metabolic cost has yet to be measured during motor learning and/or arm reaching. Here, we measured metabolic power consumption using expired gas analysis, as humans learned novel arm reaching dynamics. We hypothesized that (1) metabolic power would decrease with motor learning and (2) muscle activity and coactivation would parallel changes in metabolic power. Seated subjects made horizontal planar reaching movements toward a target using a robotic arm. The novel dynamics involved compensating for a viscous curl force field that perturbed reaching movements. Metabolic power was measured continuously throughout the protocol. Subjects decreased movement error and learned the novel dynamics. By the end of learning, net metabolic power decreased by ∼20% (∼0.1 W/kg) from initial learning. Muscle activity and coactivation also decreased with motor learning. Interestingly, distinct and significant reductions in metabolic power occurred even after muscle activity and coactivation had stabilized and movement changes were small. These results provide the first evidence of actual metabolic reduction during motor learning and for a reaching task. Further, they suggest that muscle activity may not explain changes in metabolic cost as completely as previously thought. Additional mechanisms such as more subtle features of arm muscle activity, changes in activity of other muscles, and/or more efficient neural processes may also underlie the reduction in metabolic cost during motor learning.
Differential Effects between γ-Secretase Inhibitors and Modulators on Cognitive Function in Amyloid Precursor Protein-Transgenic and Nontransgenic Mice
Authors: Mitani Yasuyuki , Yarimizu Junko , Saita Kyoko , Uchino Hiroshi , Akashiba Hiroki , Shitaka Yoshitsugu , Ni Keni , Matsuoka Nobuya
Published: February 2012

γ-Secretase inhibitors (GSIs) reduce amyloid-β (Aβ) peptides but inevitably increase the β-C-terminal fragment (β-CTF) of amyloid precursor protein (APP), potentially having undesirable effects on synapses. In contrast, γ-secretase modulators (GSMs) reduce Aβ42 without increasing β-CTF. Although the Aβ-lowering effects of these compounds have been extensively studied, little effort has been made to investigate their effects on cognition. Here, we compared the effects of two GSIs—(2S)-2-hydroxy-3-methyl-N-[(2S)-1-{[(1S)-3-methyl-2-oxo-2,3,4,5-tetrahydro-1H-3-benzazepin-1-yl]amino}-1-oxopropan-2-yl]butanamide (LY450139, semagacestat) and (2R)-2-[[(4-chlorophenyl)sulfonyl][[2-fluoro-4-(1,2,4-oxazol-3-yl)phenyl]methyl]amino-5,5,5-trifluoropentanamide (BMS-708163)—and a second-generation GSM [{(2S,4R)-1-[(4R)-1,1,1-trifluoro-7-methyloctan-4-yl]-2-[4-(trifluoromethyl)phenyl]piperidin-4-yl}acetic acid (GSM-2)] on spatial working memory in APP-transgenic (Tg2576) and nontransgenic mice using the Y-maze task. While acute dosing with either GSI ameliorated memory deficits in 5.5-month-old Tg2576 mice, these effects disappeared after 8 d subchronic dosing. Subchronic dosing with either GSI rather impaired normal cognition in 3-month-old Tg2576 mice, with no inhibition on the processing of other γ-secretase substrates, such as Notch, N-cadherin, or EphA4, in the brain. LY450139 also impaired normal cognition in wild-type mice; however, the potency was 10-fold lower than that in Tg2576 mice, indicating an APP-dependent mechanism likely with β-CTF accumulation. Immunofluorescence studies revealed that the β-CTF accumulation was localized in the presynaptic terminals of the hippocampal stratum lucidum and dentate hilus, implying an effect on presynaptic function in the mossy fibers. In contrast, both acute and subchronic dosing with GSM-2 significantly ameliorated memory deficits in Tg2576 mice and did not affect normal cognition in wild-type mice. We demonstrated a clear difference between GSI and GSM in effects on functional consequences, providing new insights into strategies for developing these drugs against Alzheimer's disease.
Dysmorphic Photoreceptors in a P23H Mutant Rhodopsin Model of Retinitis Pigmentosa Are Metabolically Active and Capable of Regenerating to Reverse Retinal Degeneration
Authors: Lee Damian C. , Vazquez-Chona Felix R. , Ferrell W. Drew , Tam Beatrice M. , Jones Bryan W. , Marc Robert E. , Moritz Orson L.
Published: February 2012

This study evaluated the capacity ofXenopus laevisretina to regenerate photoreceptor cells after cyclic light-mediated acute rod photoreceptor degeneration in a transgenic P23H mutant rhodopsin model of retinits pigmentosa. After discontinuation of cyclic light exposure, we monitored histologic progression of retinal regeneration over a 3 week recovery period. To assess their metabolomic states, contralateral eyes were processed for computational molecular phenotyping. We found that retinal degeneration in the P23H rhodopsin mutation could be partially reversed, with regeneration of rod photoreceptors recovering normal morphology (including full-length rod outer segments) by the end of the 3 week recovery period. In contrast, retinal degeneration mediated by directly induced apoptosis did not recover in the 3 week recovery period. Dystrophic rod photoreceptors with truncated rod outer segments were identified as the likely source of rod photoreceptor regeneration in the P23H retinas. These dystrophic photoreceptors remain metabolically active despite having lost most of their outer segments.
Ventral Striatum Encodes Past and Predicted Value Independent of Motor Contingencies
Authors: Goldstein Brandon L. , Barnett Brian R. , Vasquez Gloria , Tobia Steven C. , Kashtelyan Vadim , Burton Amanda C. , Bryden Daniel W. , Roesch Matthew R.
Published: February 2012

The ventral striatum (VS) is thought to signal the predicted value of expected outcomes. However, it is still unclear whether VS can encode value independently from variables often yoked to value such as response direction and latency. Expectations of high value reward are often associated with a particular action and faster latencies. To address this issue we trained rats to perform a task in which the size of the predicted reward was signaled before the instrumental response was instructed. Instrumental directional cues were presented briefly at a variable onset to reduce accuracy and increase reaction time. Rats were more accurate and slower when a large versus small reward was at stake. We found that activity in VS was high during odors that predicted large reward even though reaction times were slower under these conditions. In addition to these effects, we found that activity before the reward predicting cue reflected past and predicted reward. These results demonstrate that VS can encode value independent of motor contingencies and that the role of VS in goal-directed behavior is not just to increase vigor of specific actions when more is at stake.
The Role of a Pianist's Affective and Structural Interpretations in his Expressive Body Movement: A Single Case Study
Authors: Shoda Haruka , Adachi Mayumi
Published: February 2012

we explored how a pianist manipulates his upper body according to his interpretation of music. We asked a professional pianist to perform artistic, deadpan, and exaggerated renditions of two structurally contrasting pieces. The pianist’s affective interpretations clearly differentiated among the three renditions. The artistic rendition, representing the true nature of the piece, was compared to the contrived deadpan and exaggerated renditions. The pianist’s range of body movement in the artistic rendition differed from the other two for a fast, energetic piece, whereas it only differed from the deadpan for a slow, romantic piece. The pianist highlighted the structural contrasts within the artistic rendition by manipulating his range of body movement and by coordinating the variations between body movement and temporal/dynamical projection of tones.
Enzyme replacement therapy for Gaucher disease introduced in late adulthood
Authors: Juhász Pálma , Tóth Beáta , Maródi László , Erdős Melinda
Published: February 2012

Gaucher disease is the most prevalent lysosomal storage disorder caused by recessive mutation of the beta-glucocerebrosidase gene, which leads to massive lysosomal accumulation of glucocerebrosids especially in macrophages of bone marrow, liver and spleen. The most common presenting signs and symptoms are hepatosplenomegaly, bone pain, pathologic fractures, fatigue, bleeding tendency and recurrent infections. Regular enzyme replacement therapy which is available since 1992 in Hungary successfully reverses the symptoms of the disorder, including hematological abnormalities, bone infiltration and hepatosplenomegaly. Authors present here two cases diagnosed in late adulthood to emphasize the importance of early diagnosis and treatment. Orv. Hetil., 2012, 153, 264–270.
Current treatment of acute myeloid leukaemia in adults
Authors: Telek Béla , Rejtő László , Kiss Attila , Batár Péter , Reményi Gyula , Szász Róbert , Ujj Zsófia Ágnes , Udvardy Miklós
Published: February 2012

Recent cytogenetical findings and novel molecular biology results of acute myeloid leukaemia have shed new lights of our understanding in the diagnosis and treatment of the disease. Acute myeloid leukaemia is not only represented by the wide variety of morphological and immunophenotypic diversity but also demonstrates cytogenetical and molecular biological heterogeneity of its own. It has an unfavorable prognosis, especially in the elderly. Overall survival of younger patients (<50–60 years) has increased in the past years due to high dose chemotherapy (daunorubicine, cytarabine). But in case of unfavorable prognostic factors (not only cytogenetical but also molecular biological characters of the disease), allogeneic stem cell transplantation is needed for successful overall outcome. Better understanding the biology of acute myeloid leukaemia could establish novel targeted therapies and help us eventually to cure the disease. Orv.Hetil., 2012, 153, 243–249.
Carbon/carbon implants in the oral and maxillofacial surgery – Part 1
Authors: Szabó György , Barabás József , Németh Zsolt , Bogdán Sándor
Published: February 2012

Over the past 20–30 years various carbon implant materials have become more interesting, because they are well accepted by the biological environment. The traditional carbon-based polymers give rise to many complications. The polymer complication may be eliminated through carbon fibres bound by pyrocarbon (carbon/carbon). Aim: The aim of this study is to present the long-term results of carbon/carbon implants. Methods: Mandibular reconstruction was performed with pure (99.99%) carbon implants in 16 patients. Predominantly tumorous cases were included (10 malignant tumors, 4 large cystic lesions and 2 augmentative processes). Results: Because the interventions had been performed 6–8 years before the last follow-up visit, the authors report long-term results. Of the 16 patients, the implants had to be removed earlier in 5 patients because of the defect that arose on the oral mucosa above the carbon plates. The most probable cause of this complication was the strain in the oral mucosa and disturbances in its blood supply (previous surgery, irradiated tissue, etc.). During the long-term follow-up, plate fracture, loosening of screws, infection or inflammation around the carbon/carbon implants were not observed. After 8 years one carbon implant was substituted with an autogenous bone. Conclusions: The clinical conclusion is that if the soft part cover is appropriate, the carbon implants are cosmetically and functionally more suitable than titanium plates. The structural and chemical investigation of the removed implant will be published in the near future. Orv. Hetil., 2012, 153, 257–262.
Raman Spectrum Modification of CdSe/ZnS Quantum Dots at the Bio-conjugation to IgG Antibodies
Authors: Diaz Cano A. I. , Douda J. , Gonzalez Vargas C. R. , Gazarian K.
Published: February 2012

The paper presents the analysis of Raman scattering spectra of non-conjugated and bio-conjugated CdSe/ZnS core–shell quantum dots in the range of Raman shifts of 80 - 2000 cm-1. Commercial CdSe/ZnS QDs covered by polymer and characterized by color emission with the maxima at 605 and 655 nm (1.89 and 2.04 eV) were used. Raman scattering spectra were measured at 300K and the excitation by the line 785.0 nm of a solid state LED. The analysis of Raman spectra has shown that the QD bio-conjugation to the immunoglobulin G (IgG) antibodies of the Pseudorabies virus is accompanied by the changes of the intensity of Raman lines related to the CdSe/ZnS core/shell QDs, PEG polymer covered QDs, the Si substrate and/or some organic groups of antibody molecules. The comparison of Raman spectra of CdSe/ZnS QDs with different sizes in non-conjugated and bio-conjugated states gives the opportunity to detect the bio-conjugation without mistake.
ZrO2 Doped with Cobalt Nanoparticles to Detect UV Radiatiion
Authors: Villa Sánchez Gerardo , Mendoza Anaya Demetrio , Gutiérrez-Wing Claudia , González Martínez. Pedro R. , Olea Mejía Oscar F.
Published: February 2012

This paper reports the synthesis and characterization of the ZrO2:Co nanosystem, by incorporation of Co nanoparticles (CoNP) into tetragonal and monoclinic zirconia. ZrO2 was synthesized by a sol-gel process, while cobalt nanoparticles were obtained through a colloidal method by chemical reduction of a metal precursor. CoNP were incorporated by two different approaches: during the synthesis of the ZrO2 and by classical impregnation of CoNP on zirconium oxide. The size of Cobalt nanoparticles was controlled through the concentration of reducing agent (NaBH4) and passivanting agent (1-dodecanethiol). According to SEM and TEM analysis, the diameter of the zirconium oxide particles depends on the CoNP concentration added; the particle size for pure zirconia treated at 500°C is 200 nm and 180 nm for ZrO2:Co. X-Ray diffraction showed presence of the tetragonal and monoclinic zirconia, but the abundance of each one depends on the Co nanoparticles and thermally treatment.
ZrO2 Nanopowders Doped with Eu: SEM, XRD and UV Spectroscopy Studies
Authors: Villa Sánchez Gerardo , Mendoza Anaya Demetrio , Palma Palma Emmanuel , Gutiérrez Wing Claudia E. , Pérez Hernández Raúl , Olea Mejía Oscar F. , García Santibañez Federico
Published: February 2012

Zirconia nanopowders doped with different concentrations of Eu were prepared by the solgel method followed by a thermal treatment at 500°C. Morphological and crystallographic characteristics were studied by scanning electron microscopy, X-Ray diffraction and UV spectroscopoy. Results showed a modification of the size of nanopowder particles when the concentration of Eu is increased from 0.0 to 4.0 wt%. Also, at lower concentration of Eu the tetragonal ZrO2 is the most abundant phase while high concentrations of Eu lead to the formation of the monoclinic phase. The UV spectroscopy of ZrO2 samples shows two main absorption peaks at 228 and 214 nm. The novel characteristics of the ZrO2 nanopowders doped with Eu allow us to propose them for use as solar UV radiation detectors.
Temperature and Time-Dependent Ion Diffusion Across Stainless Steel-Zirconium Film Interface Studied by Scanning Surface Potential.
Authors: Hawley M.E. , Hollis K.J. , Dickerson P.O.
Published: February 2012

Zirconium is of interest in the development of high-density diffusion barriers in nuclear reactor applications because of its low thermal neutron absorption cross section and good thermal and mechanical properties. It is used in these applications to protect the low enriched fuel from interacting directly with the cladding material to prevent swelling and cracking of the fuel. In this work, we investigated the use of plasma spraying as a method to produce high quality, dense Zr barrier coatings over large surface areas. A thin sheet of 21Cr-6Ni-9Mn stainless steel (SS) was used as the substrate material. Both sides of the SS sheet were coated, one side at a time. A transfer arc (TA) current between a torch and the substrate was used to vary the substrate temperature to explore the effect of temperature and time on the film grain size, interface quality, and film porosity. The films were characterized using light optical microscopy (LOM), scanning probe microscopy (SPM) and Kelvin probe force microscopy (KPFM) and EDS-SEM Although the film quality did improved with temperature, at the elevated substrate temperatures used in this study, metal atoms from the substrate diffused into and, at the highest temperature and longest time, through the Zr coatings.
Characterization of InGaN and InAlN Epilayers by Microdiffraction X-Ray Reciprocal Space Mapping
Authors: Kachkanov V. , Dolbnya I.P. , O’Donnell K.P. , Lorenz K. , Pereira S. , Martin R.W. , Edwards P.R. , Watson I.M.
Published: February 2012

We report a study of InGaN and InAlN epilayers grown on GaN/Sapphire substrates by microfocused three-dimensional X-ray Reciprocal Space Mapping (RSM). The analysis of the full volume of reciprocal space, while probing samples on the microscale with a focused X-ray beam, allows us to gain uniquely valuable information about the microstructure of III-N alloy epilayers. It is found that “seed” InGaN mosaic nanocrystallites are twisted with respect to the ensemble average and strain free. This indicates that the growth of InGaN epilayers follows the Volmer-Weber mechanism with nucleation of “seeds” on strain fields generated by thea-type dislocations which are responsible for the twist of underlying GaN mosaic blocks. In the case of InAlN epilayer formation of composition gradient was observed at the beginning of the epitaxial growth.
Enhanced Emission from InxGa1-xN-based LED Structures Using III-Nitride based Distributed Bragg Reflector
Authors: Lee K. , Kadiyala A. , Rodak L. E. , Goswami R. , Kumbham V. , Bearce B. A. , Justice J. , Peacock J. , Dawson J. M. , Hornak L. A. , Korakakis D.
Published: February 2012

InxGa1-xN-based LED structures were grown on digital AlxGa1-xN/GaN DBR substrate to enhance emission extraction. Same LED structure was grown on sapphire substrate as a comparison. LEDs grown on DBR substrate exhibited similar IV characteristics to that grown on sapphire substrate but emission-angle-dependent EL spectra were observed. Also, the resonant vertical cavity modes were observed in EL spectra of LEDs with DBR structure and compared to simulated results. Image processing analysis results show that light extraction of LEDs is enhanced with use of DBR substrate.
Low-Thermal-Budget Solution Processing of Thin Films of Zinc Ferrite and Other Complex Oxides
Authors: Sai Ranajit , Kulkarni Suresh D. , Vinoy K. J. , Bhat Navakanta , Shivashankar S. A.
Published: February 2012

Further miniaturization of magnetic and electronic devices demands thin films of advanced nanomaterials with unique properties. Spinel ferrites have been studied extensively owing to their interesting magnetic and electrical properties coupled with stability against oxidation. Being an important ferrospinel, zinc ferrite has wide applications in the biological (MRI) and electronics (RF-CMOS) arenas. The performance of an oxide like ZnFe2O4depends on stoichiometry (defect structure), and technological applications require thin films of high density, low porosity and controlled microstructure, which depend on the preparation process. While there are many methods for the synthesis of polycrystalline ZnFe2O4powder, few methods exist for the deposition of its thin films, where prolonged processing at elevated temperature is not required. We report a novel, microwave-assisted, low temperature (<100°C) deposition process that is conducted in the liquid medium, developed for obtaining high quality, polycrystalline ZnFe2O4thin films on technologically important substrates like Si(100). An environment-friendly solvent (ethanol) and non-hazardous oxide precursors (β-diketonates of Zn and Fe in 1:2 molar ratio), forming a solution together, is subjected to irradiation in a domestic microwave oven (2.45 GHz) for a few minutes, leading to reactions which result in the deposition of ZnFe2O4films on Si (100) substrates suspended in the solution. Selected surfactants added to the reactant solution in optimum concentration can be used to control film microstructure. The nominal temperature of the irradiated solution, i.e., film deposition temperature, seldom exceeds 100°C, thus sharply lowering the thermal budget. Surface roughness and uniformity of large area depositions (50x50 mm2) are controlled by tweaking the concentration of the mother solution. Thickness of the films thus grown on Si (100) within 5 min of microwave irradiation can be as high as several microns. The present process, not requiring a vacuum system, carries a very low thermal budget and, together with a proper choice of solvents, is compatible with CMOS integration. This novel solution-based process for depositing highly resistive, adherent, smooth ferrimagnetic films on Si (100) is promising to RF engineers for the fabrication of passive circuit components. It is readily extended to a wide variety of functional oxide films.
Using Mass Spectrometry to Investigate the Structural Features of Photocrosslinked Co-Networks based on Gelatin and Poly(ethylene glycol) Methacrylates
Authors: Pierce Benjamin F. , Neffe Axel T. , Lendlein Andreas
Published: February 2012

Gelatin was functionalized with glycidyl methacrylate and photocrosslinked in the presence of poly(ethylene glycol) dimethacrylate (PEGDMA) or poly(ethylene glycol) monomethacrylate (PEGMA) to create a biopolymer-based system with tailorable properties. These co-networks were hydrolyzed using 6 M HCl and the degradation products were analyzed and identified using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry. This technique successfully identified gelatin-derived peptides such as FLPEPPE, SFLPEPPE, and SFLPEPPEE as well as an accompanying PEG-g-poly(methacrylic acid) component. No oligo- or polymethacrylates were monitored at any molecular weight range above m/z = 500, which indicated that they possessed lower molecular weights. An in vitro hydrolytic degradation experiment performed in pH 7.4 PBS buffer solution at 37 °C showed that these networks, which were prepared without the addition of a potentially toxic photoinitiator, exhibited mass loss of up to 50 wt% at 6 weeks of incubation time. These results provide valuable insight into how these functional gelatin-based co-network biomaterials will perform in a biological setting.
Shape-Memory Properties of Nanocomposites based on Poly(ω-pentadecalactone) and Magnetic Nanoparticles
Authors: Razzaq M. Y. , Behl M. , Lendlein A.
Published: February 2012

Magneto-sensitive shape-memory polymers (SMP) obtained by incorporating magnetic nanoparticles in a SMP matrix are an emerging class of multifunctional materials. The incorporation of the nanoparticles enhanced the mechanical properties and in addition enabled remote actuation by exposure to alternating magnetic fields. Here, we report on the thermallyinduced shape-memory properties of such magneto-sensitive nanocomposites based on poly(ω- pentadecalactone) (PPDL) switching segments and magnetic nanoparticles. A series of nanocomposites were prepared by crosslinking of poly(ω-pentadecalactone)dimethacrylate (Mn = 2800 g·mol-1and 5100 g·mol-1) in the presence of silica encapsulated magnetic nanoparticles. The silica shell of the nanoparticles was selected to enhance the distribution and compatibility of the nanoparticles with the polymer matrix. Thermal and mechanical properties of the nanocomposites were explored as a function of PPDL chain length and nanoparticle weight content. All nanocomposites exhibited excellent shape-memory properties with shape fixity rates between 86% and 93% and shape recovery rates above 97%. Potential applications for such shape-memory nanocomposites include smart implants, medical instruments, which could be controlled on demand by thermal or indirect magnetic heating.
Resonating UHF Study on Electron Correlation in a Ground State of Two Electrons Confined in 2D Quantum Dot
Authors: Okunishi Takuma , Takeda Kyozaburo
Published: February 2012

We theoretically study the spatial and temporal fluctuation of two electrons confined in a semiconductor quantum dot (QD). Eigenstates are determined by the resonating unrestricted Hartree-Fock (res-UHF) approach in order to take into account the electron correlation via the configuration interaction (CI). The time-dependent (TD) wave function is, then, expanded by the UHF solutions, and the CI treatment is combined with the TD Schrödinger equation (TD-CI). The present TD-CI approach has an advantage to study how the electron correlation fluctuates the multi-electron state spatially and/or temporally through the multi-reference description of many-electron wave functions.
A View of Pragmatics in a Social Semiotic Perspective
Authors: Hasan Ruqaiya
Published: February 2012

The constrained and constraining conception of ‘linguistics proper’ in the 1970s dominant linguistics encouraged the recognition of several sub/disciplines concerned in some way with the study of language. Viewed at first as optional extra to ‘doing real linguistics’, these disciplines have struggled under the weight of their origin to gain a legitimate status: on the one hand, they are said to concern areas of language study which just cannot be ignored if one’s interest is in understanding the nature of language, on the other, their exclusion from the field of ‘linguistics proper’, raises doubts: these claims cannot both be upheld. The dilemma faces pragmatics as much as it does sociolinguistics; the resolution seems to turn on ideas about language. In one of its definitions, pragmatics claims to be ‘the science of language as seen in relation to its users’ (Mey 1993: 5). This suggests the idea of language as a social semiotic. In this paper I attempt to bring pragmatics face to face with language as a social semiotic by spelling out what might be implied by ‘language as seen in relation to its users’.
“We can probably go there”
Authors: Xiao Tangjin
Published: February 2012

Most linguistic studies have focused on modal verbs, modal adverbs, or modal nouns separately, but little attention has been paid to the co-occurrence of modal devices. This paper proposes a new term “modal satellite adverbs” (MSAs), i.e. the co-occurrence of modal verbs and some adverbs, and studies their semantic types, distributions, and functions of modality supplementing in four genres, namely, academic writings, public speeches, journalistic interviews, and law and regulations. The discourse functions and interpersonal functions that MSAs perform are referred to as modality supplementing. Based mainly on the Systemic Functional Linguistic approach to interpersonal metafunction as well as authentic corpora, this paper shows that MSAs can perform the discourse functions of value adaptation, modal synergy and generic prominence. Also, it indicates that such interpersonal meanings as solidarity, deference and hierarchy are displayed differently in the four genres. This project is an extension of Systemic Functional Linguistic studies on interpersonal metafunction.
The Interactional Function of Japanese Interactive Markers yo and sa
Authors: Ogi Naomi
Published: February 2012

This study investigates the interactional function of Japanese interactive markers yo and sa in conjunction with the notion of involvement, and sheds light on some issues of verbal exchange in spoken discourse. The study argues that these markers commonly share the function of signalling the speaker’s attitude of inviting the hearer’s involvement in a ‘monopolistic’ manner, by which the speaker is committed to enhance his/her position as a deliverer of the contents/feeling conveyed in the utterance. Further, each marker indicates the speaker’s monopolistic attitude in its unique way: yo signals the speaker’s monopolistic attitude of ensuring the hearer’s understanding of the contents/feeling conveyed in the utterance, while sa signals the speaker’s monopolistic attitude of presenting the contents/feeling conveyed in the utterance as a matter of course for him/her. Based on these functions, their co-occurrence restrictions with modal expressions and their use in social contexts are also discussed.
Radio Miscommunication
Authors: Estival Dominique , Molesworth Brett
Published: February 2012

Communicating effectively via the radio in General Aviation (GA) is a challenging task for most pilots. This is even more challenging for non-native speakers of English (EL2) who are required to master not only a second language but “Aviation English” to communicate with both Air Traffic Control (ATC) and other pilots. In two pilot studies conducted in Eastern Australia, we investigated the ability of GA pilots, both native and non-native speakers of English, to effectively communicate with ATC and with other pilots over the radio, in order to assess the contribution of native language to incidents of miscommunication and the impact it may have on air safety. The results revealed that indeed communication is difficult for EL2 pilots as well as native pilots. Irrespective of native language, pilots found communicating with one another the most challenging task while communicating with ATC was found to be the least challenging. These results are discussed from an operational perspective.