bluuebunny/crossref_metadata_2025 huggingface dataset:
Persistence and Learning: Success Factors of Taiwanese Firms in International Markets
Authors: Johnson Joseph , Yin Eden , Tsai Hueiting
Published: August 2009

A relatively recent trend in international marketing is the rising number of firms from nontriad countries seeking growth and profits from foreign markets. Yet no study has examined the international performance of these firms. How successful have their efforts been? What factors drive their success? The authors examine these questions by building a theory-based conceptual framework that links firm international performance to its antecedents. They test the framework using a sample of 110 Taiwanese firms. The key findings are as follows: (1) The internationalization–performance relationship is characterized by a joint U + N shape, (2) learning capacity is positively associated with international performance, and (3) research and development intensity is not a key driver of performance. Though based on a sample of Taiwanese firms only, these results imply that nontriad firms embarking on internationalization must persist despite early setbacks, must develop their learning capacity, and should not develop extensive research and development capabilities while internationalizing. The authors conclude with a discussion of the reasons for these findings.
The Role of Customer Gratitude in Relationship Marketing
Authors: Palmatier Robert W. , Jarvis Cheryl Burke , Bechkoff Jennifer R. , Kardes Frank R.
Published: August 2009

Most theories of relationship marketing emphasize the role of trust and commitment in affecting performance outcomes; however, a recent meta-analysis indicates that other mediating mechanisms are at work. Data from two studies—a laboratory experiment and a dyadic longitudinal field survey—demonstrate that gratitude also mediates the influence of a seller's relationship marketing investments on performance outcomes. Specifically, relationship marketing investments generate short-term feelings of gratitude that drive long-lasting performance benefits based on gratitude-related reciprocal behaviors. The authors identify a set of managerially relevant factors and test their power to alter customer perceptions of relationship marketing investments to increase customer gratitude, which can make relationship marketing programs more effective. Overall, the research empirically demonstrates that gratitude plays an important role in understanding how relationship marketing investments increase purchase intentions, sales growth, and share of wallet.
Testing the Value of Customization: When Do Customers Really Prefer Products Tailored to Their Preferences?
Authors: Franke Nikolaus , Keinz Peter , Steger Christoph J.
Published: August 2009

Recently, researchers have paid increasing attention to the marketing strategy of customization. A key assumption is that customized products create higher benefits for customers than standard products because they deliver a closer preference fit. The prerequisite for this effect is the ability to obtain precise information on what customers actually want. But are customers able to specify their preferences that precisely? Several theoretical arguments raise doubts about this, implicitly challenging the value of customization. The authors conduct two studies in which they find that products customized on the basis of expressed preferences bring about significantly higher benefits for customers in terms of willingness to pay, purchase intention, and attitude toward the product than standard products. The benefit gain is higher if customers have (1) better insight into their own preferences, (2) a better ability to express their preferences, and (3) greater product involvement. This suggests that customization has the potential to be a powerful marketing strategy if these conditions are met. In the opposite case, firms willing to serve heterogeneous customer preferences need to adapt their customization systems in such a way that they explicitly address the customers’ inability to provide valid preference information.
The Interplay among Category Characteristics, Customer Characteristics, and Customer Activities on in-Store Decision Making
Authors: Inman J. Jeffrey , Winer Russell S. , Ferraro Rosellina
Published: August 2009

The authors explore product category and customer characteristics that affect consumers’ likelihood of engaging in unplanned purchases. In addition, they examine consumer activities that can exacerbate or limit these effects. The authors employ a hierarchical modeling approach to test their hypotheses using a data set of in-store intercept interviews conducted with 2300 consumers across 28 stores. The results show that category characteristics, such as purchase frequency and displays, and customer characteristics, such as household size and gender, affect in-store decision making. Moreover, although the analysis reveals that the baseline probability of an unplanned purchase is 46%, the contextual factors can drive this probability as high as 93%. The results support the predictions that list use, more frequent trips, limiting the aisles visited, limiting time spent in the store, and paying by cash are effective strategies for decreasing the likelihood of making unplanned purchases.
Managing Dynamics in a Customer Portfolio
Authors: Homburg Christian , Steiner Viviana V. , Totzek Dirk
Published: August 2009

Although highly relevant for marketing practice, few studies provide conceptual and empirical insights into customer portfolio management. Furthermore, most approaches to analyzing customer portfolios are static. This article discusses three neglected key issues relevant for a dynamic customer portfolio analysis: (1) Does a static versus a dynamic valuation lead to a different prioritization of customer segments in a portfolio? (2) How does offensive or defensive management of segment dynamics affect portfolio value? and (3) Do reliable predictors for dynamics of a customer's position in the portfolio exist? As a tool for customer portfolio analysis, the authors develop a segment-based customer-lifetime-value model. They capture customer dynamics by analyzing how customers switch between segments of different values across time. The authors apply their tool with longitudinal data from four firms with up to 300,000 customers. The results from the empirical analysis and a simulation study provide answers to the three key issues raised. First, compared with a dynamic analysis, a static approach overestimates the value of some customer segments but underestimates others. Second, a defensive versus offensive management of value dynamics is relatively more appropriate for middle-tier segments, whereas the opposite holds true for bottom-tier segments. Third, general customer characteristics and aggregated transaction characteristics indicate future segment dynamics, whereas specific product usage data differentiate customers according to current value.
X-ray Study of the Sigma Phase in Various Alloy Systems
Authors: Duwez Pol , Baen Spencer R.
Published: August 2009

This paper presents a critical review of the X-ray diffraction data of the sigma phase in the binary alloys of iron, cobalt, nickel, chromium, and vanadium. Although the crystal structure of the sigma phase is still unknown, a tentative tetragonal unit cell is suggested to describe the structure, at least as a first approximation. On the basis of this cell the lattice parameters of the various binary sigma phases are computed. The case of a ternary sigma solid solution in the iron-chromium-molybdenum system is also discussed and the influence of molybdenum on the lattice parameter of sigma is described. A short discussion is given on the occurrence of the sigma phase in binary alloys and its relation to atomic diameter and crystal structure of the two component metals.
Some Notes on the Structure and Impact Resistance of Columbium-Bearing 18—8 Steels After Exposure to Elevated Temperatures
Authors: Binder W. O.
Published: August 2009

The influence of columbium on the impact properties of 18-8 steels has been studied in steels containing 8 to 16 per cent nickel and 0 to 3 per cent columbium. The addition of more than 2 per cent columbium decreases the toughness of the steel in the annealed condition due to the formation of M6C carbide and the compound Fe3Cb2. Long heating at 650 and 870 C. (1200 and 1600 F.) has no significant influence on impact toughness of steels containing up to 2 per cent columbium, but it is more detrimental to higher columbium steels. Positive X-ray identification of sigma phase was obtained after long periods at 650 C. (1200 F.) over the range 8 to 16 per cent nickel and 0.75 to 3 per cent columbium. However, the steels do not form large amounts of sigma even though strained at elevated temperatures. Cold working, followed by low-temperature annealing, accelerates the rate of precipitation of sigma phase and favors particle growth, whereas, high-temperature annealing inhibits precipitation and particle growth. The precipitation of sigma phase in a critical particle size is believed to have a beneficial effect on creep strength.
Observations of the Effect of Sigma on the Mechanical Properties of Columbium-Stabilized Weldments in Austenitic Stainless Steels
Authors: Schmitz F. W. , Scheil M. A.
Published: August 2009

A summary of the investigation of 13 weldments in 1 1/2-in, thick T347 stainless steel on the basis of heat treatments given for stress removal reveals that ductility of all weld metal tension test bars is affected by the following variations: 1. Maximum ductility of 30 per cent and over is obtained in the “aswelded” condition with ferrite content between 3 and 8 per cent when no sigma is present. 2. Ductility varying between about 10 to 30 per cent is obtained after heat treatments producing sigma contents from 5 to 1 per cent. 3. Weld metal with ferrite in the as-deposited condition does not always sigmatize to the full extent possible. 4. The size and distribution of the sigma phase varies the ductility. Larger particles of sigma in a segregated pattern are more effective in lowering ductility. 5. Variations of welding technique such as thin and thick weld layers and peening affect the ductility only in so far as the amount of sigma produced on heat treatment.
5-HT4Receptor-Mediated Neuroprotection and Neurogenesis in the Enteric Nervous System of Adult Mice
Authors: Liu Min-Tsai , Kuan Yung-Hui , Wang Jingwen , Hen René , Gershon Michael D.
Published: August 2009

Although the mature enteric nervous system (ENS) has been shown to retain stem cells, enteric neurogenesis has not previously been demonstrated in adults. The relative number of enteric neurons in wild-type (WT) mice and those lacking 5-HT4receptors [knock-out (KO)] was found to be similar at birth; however, the abundance of ENS neurons increased during the first 4 months after birth in WT but not KO littermates. Enteric neurons subsequently decreased in both WT and KO but at 12 months were significantly more numerous in WT. We tested the hypothesis that stimulation of the 5-HT4receptor promotes enteric neuron survival and/or neurogenesis.In vitro, 5-HT4agonists increased enteric neuronal development/survival, decreased apoptosis, and activated CREB (cAMP response element-binding protein).In vivo, in WT but not KO mice, 5-HT4agonists induced bromodeoxyuridine incorporation into cells that expressed markers of neurons (HuC/D, doublecortin), neural precursors (Sox10, nestin, Phox2b), or stem cells (Musashi-1). This is the first demonstration of adult enteric neurogenesis; our results suggest that 5-HT4receptors are required postnatally for ENS growth and maintenance.
Early Development of the Thalamic Inhibitory Feedback Loop in the Primary Somatosensory System of the Newborn Mice
Authors: Evrard Alexis , Ropert Nicole
Published: August 2009

Spontaneous neuronal activity plays an important role during the final development of the brain circuits and the formation of the primary sensory maps. In young rats, spindle bursts have been recorded in the primary somatosensory cortex. They are correlated with spontaneous muscle twitches and occur before active whisking. They bear similarities with the spindles recorded in adult brain that occur during early stages of sleep and rely on a thalamic feedback loop between the glutamatergic nucleus ventroposterior medialis (nVPM) and the GABAergic nucleus reticularis thalami (nRT). However, whether a functional nVPM–nRT loop exists in newborn rodents is unknown. We studied the reciprocal synaptic connections between nVPM and nRT in thalamic acute slices from mice from birth [postnatal day 0 (P0)] until P9. We first demonstrated that nVPM-to-nRT EPSCs could be distinguished from corticothalamic EPSCs by their inhibition by 5-HT attributable to the transient expression of functional presynaptic serotonin 1B receptors. The nVPM-to-nRT EPSCs and nRT-to-nVPM IPSCs were both detected the first day after birth; their amplitude near 2 nS was relatively stable until P5. At P6–P7, there was a rapid and simultaneous increase of both nVPM-to-nRT EPSCs and nRT-to-nVPM IPSCs that reached 8 and 9 nS, respectively. Our results show that the thalamic synapses implicated in spindle activity are functional shortly after birth, suggesting that they could already generate spindles during the first postnatal week. Our results also suggest an inhibitory action of 5-HT on the spindle bursts of the newborn mice.
Synaptic Activity Reduces Intraneuronal Aβ, Promotes APP Transport to Synapses, and Protects against Aβ-Related Synaptic Alterations
Authors: Tampellini Davide , Rahman Nawreen , Gallo Eduardo F. , Huang Zhenyong , Dumont Magali , Capetillo-Zarate Estibaliz , Ma Tao , Zheng Rong , Lu Bao , Nanus David M. , Lin Michael T. , Gouras Gunnar K.
Published: August 2009

A central question in Alzheimer's disease research is what role synaptic activity plays in the disease process. Synaptic activity has been shown to induce β-amyloid peptide release into the extracellular space, and extracellular β-amyloid has been shown to be toxic to synapses. We now provide evidence that the well established synaptotoxicity of extracellular β-amyloid requires γ-secretase processing of amyloid precursor protein. Recent evidence supports an important role for intraneuronal β-amyloid in the pathogenesis of Alzheimer's disease. We show that synaptic activity reduces intraneuronal β-amyloid and protects against β-amyloid-related synaptic alterations. We demonstrate that synaptic activity promotes the transport of the amyloid precursor protein to synapses using live cell imaging, and that the protease neprilysin is involved in reduction of intraneuronal β-amyloid with synaptic activity.
Spectrotemporal Response Properties of Inferior Colliculus Neurons in Alert Monkey
Authors: Versnel Huib , Zwiers Marcel P. , van Opstal A. John
Published: August 2009

Because of its central position in the ascending auditory pathway, its large number of converging auditory brainstem inputs, and its fundamental role as a relay to auditory cortex and midbrain superior colliculus, the mammalian inferior colliculus (IC) is regarded pivotal for the integration of acoustic spectral–temporal cues to mediate sound-evoked behavior. However, detailed quantitative analyses of spectrotemporal neural responses are scarce. Moreover, most studies have been performed in anesthetized preparations, and it is unclear how to extrapolate findings to awake and behaving animals. Here, we characterize spectrotemporal receptive fields (STRFs) of single units in alert monkey IC by using a variety of broadband sounds with rippled amplitude spectra. We measured the response sensitivity to the ripple parameters density, Ω (cycles/octave), velocity,w(hertz), and direction selectivity,D. We observed a variety of dynamic STRFs, with a strong preference for low ripple densities, and a generally weak direction selectivity. Most cells preferred dynamic rippled stimuli above pure amplitude modulated noise (i.e., Ω = 0). Half of the cells could be characterized by good spectral–temporal separability, in which the ripple transfer function can be written asT(w, Ω) =F(w) ×G(Ω). Inseparability could be attributed to a difference in responses to up and downward direction with respect to both amplitude and temporal phase. We tested linearity of IC neurons by using the STRF to predict neural responses to natural stimuli and broadband noise and discuss our results in the light of findings obtained from auditory cortex.
Essential and Synergistic Roles of RP1 and RP1L1 in Rod Photoreceptor Axoneme and Retinitis Pigmentosa
Authors: Yamashita Tetsuji , Liu Jiewu , Gao Jiangang , LeNoue Sean , Wang Changguan , Kaminoh Jack , Bowne Sara J. , Sullivan Lori S. , Daiger Stephen P. , Zhang Kang , Fitzgerald Malinda E. C. , Kefalov Vladimir J. , Zuo Jian
Published: August 2009

Retinitis pigmentosa 1 (RP1) is a common inherited retinopathy with variable onset and severity. TheRP1gene encodes a photoreceptor-specific, microtubule-associated ciliary protein containing the doublecortin (DCX) domain. Here we show that another photoreceptor-specific Rp1-like protein (Rp1L1) in mice is also localized to the axoneme of outer segments (OSs) and connecting cilia in rod photoreceptors, overlapping with Rp1.Rp1L1−/− mice display scattered OS disorganization, reduced electroretinogram amplitudes, and progressive photoreceptor degeneration, less severe and slower than inRp1−/− mice. In single rods ofRp1L1−/−, photosensitivity is reduced, similar to that ofRp1−/−. While individual heterozygotes are normal, double heterozygotes ofRp1andRp1L1exhibit abnormal OS morphology and reduced single rod photosensitivity and dark currents. The electroretinogram amplitudes of double heterozygotes are more reduced than those of individual heterozygotes combined. In support, Rp1L1 interacts with Rp1 in transfected cells and in retina pull-down experiments. Interestingly, phototransduction kinetics are normal in single rods and whole retinas of individual or doubleRp1andRp1L1mutant mice. Together, Rp1 and Rp1L1 play essential and synergistic roles in affecting photosensitivity and OS morphogenesis of rod photoreceptors. Our findings suggest that mutations inRP1L1could underlie retinopathy or modify RP1 disease expression in humans.
Crystal structure of a p-tert-butylcalix[8]arene – N-methyl-morpholine complex
Authors: Mecca Tommaso , Consoli Grazia Maria Letizia , Geraci Corrada , Camalli Mercedes , Campi Gaetano , Spagna Riccardo
Published: August 2009

p-tert-Butyl-calix[8]arene crystallizes with six molecules of N-methyl-morpholine in a triclinic lattice, space group P1 with a = 12.142(3) Å, b = 16.596(4) Å, c = 17.211(2) Å, α = 83.72(2)°, β = 80.66(2)°, γ = 69.55(2)°, Z = 1. The formation of hydrogen bonds with two molecules of N-methyl-morpholine, induces the calix[8]arene skeleton to adopt a chair-like conformation in which two 3/4-cone moieties are oriented above and below the mean molecular plane, respectively. The other four solvent molecules per unit cell simply fill the interstitial voids in a “like-tubular” solid state assembly built by p-tert-butylcalix[8]arene molecules piled along the a-axis direction.
Synthesis of a new α-aminophosphonate library. Crystal structure of p-XC6H4–NH–CH(p-BrC6H4)–P(O)(OiPr)2 (X = H, Br, CH3O)
Authors: Babashkina Maria G. , Safin Damir A. , Bolte Michael , Klein Axel
Published: August 2009

A new library of α-aminophosphonates of common formula R1NH–CH(R)–P(O)(OiPr)2, containing substituted phenyl and pyridine groups R and R1, were synthesized and characterized by IR, 1H, 31P spectroscopy and elemental analysis. Crystal and molecular structures of three α-aminophosphonates p-XC6H4–NH–CH(p-XC6H4)–P(O)(OiPr)2 (X = H, Br, CH3O) were established by single crystal X-ray diffraction.
Structural features of intermetallic phases in the Ca–Zn–Al system
Authors: Pani Marcella , Fornasini Maria L. , Mazzone Donata , Merlo Franco
Published: August 2009

The Ca–Zn–Al system has been investigated in the region from 8 to 33 at% Ca. The results show that the following phases are solid solutions based on the corresponding known binary compounds: Ca(Zn1–x
Al
x
)3 (x = 0 – 0.23, CaZn3 type), Ca(Zn1–x
Al
x
)4 (x = 0.47 – 1.00, BaAl4 type), Ca1–y
(Zn1–x
Al
x
)5+2y (x = 0 – 0.12 and y = 0 – 0.12, CaCu5-derived TbCu7 type), Ca(Zn1–x
Al
x
)11 (x = 0 – 0.018, BaCd11 type), while the phase Ca2(Zn1–x
Al
x
)17 (x = 0.05 – 0.17, Th2Zn17 type) exists with a ternary composition only. In all pseudobinary systems the cell volume generally increases with increasing Al content, as expected for the higher atomic volume of Al compared with Zn. A substitution of Al for Zn is generally observed, but preferential occupations, namely different Al/Zn ratio values, occur for different crystallographic sites. This phenomenon gives rise to anomalous trends in the variations of the lattice parameters.
Temozolomide treatment of a pituitary carcinoma and two pituitary macroadenomas resistant to conventional therapy
Authors: Hagen C , Schroeder H D , Hansen S , Hagen C , Andersen M
Published: August 2009

Objective

Aggressive pituitary tumours may be difficult to treat. Temozolomide (TMZ) is an alkylating cytostaticum. In a small number of cases, TMZ therapy has been reported to reduce pituitary tumour size and hormone hypersecretion.

Design

We present three patients with pituitary tumours treated with TMZ. One tumour was initially a macroprolactinoma that developed into a mixed GH- and prolactin-secreting carcinoma (patient A). To our knowledge, this is the first published in English literature. Two adenomas, a macroprolactinoma (patient B) and a clinically non-functioning pituitary adenoma (patient C), were highly invasive. The three patients suffered from extensive tumour mass effects, and all tumours were resistant to conventional treatment.

Method

TMZ, 150–200 mg/m2 of body surface area was administered orally for 5 days during each 28-day cycle.

Result

During TMZ therapy, tumour sizes were significantly reduced, hormone levels normalized and symptoms of mass effects decreased in all three cases. The carcinoma was treated from 2004 to 2006 (23 months). Three years after the terminating treatment, the tumour has not regrown and hormone levels are normalized. Immunohistochemical staining for methylguanine DNA methyltransferase (MGMT) was negative in two patients (A and B), and in one patient (C) a few nuclei stained positive.

Conclusion

TMZ therapy significantly decreased tumour volume, hormone hypersecretion and symptoms in all three patients, corresponding to the pathological findings regarding MGMT. TMZ therapy may be a new option for the treatment of resistant pituitary adenomas.
Influence of Recombinant Human Platelet‐Derived Growth Factor on Lateral Ridge Augmentation Using Biphasic Calcium Phosphate and Guided Bone Regeneration: A Histomorphometric Study in Dogs
Authors: Schwarz Frank , Sager Martin , Ferrari Daniel , Mihatovic Ilja , Becker Jürgen
Published: August 2009

Background: The present study investigated the effects of recombinant human platelet‐derived growth factor‐BB (rhPDGF‐BB) on initial bone formation following lateral ridge augmentation using biphasic calcium phosphate (BCP) in combination with a native collagen membrane (CM) in dogs.

Methods: Eight chronic‐type mandibular lateral ridge defects in four beagle dogs (two defects each) were randomly allocated in a split‐mouth design to BCP + rhPDGF‐BB + CM (test) or BCP + CM (control). After 3 weeks, dissected blocks were prepared for immunohistochemical (angiogenesis‐transglutaminase II [TG]) and histomorphometric analysis (e.g., augmented area [AA] and mineralized tissue [MT]). The biologic activity of rhPDGF‐BB soak‐loaded BCP was verified by means of alkaline phosphatase and lactate dehydrogenase assays in a SaOs‐2‐osteoblast‐like cell culture.

Results: Both groups exhibited a comparable pattern of blood vessel and bone formation that mainly originated from the adjacent alveolar bone. However, test sites revealed a pronounced TG antigen reactivity, which was associated with statistically significant higher mean AA (8.5 ± 0.9 mm2 versus 7.1 ± 1.1 mm2) and MT (2.7 ± 0.9 mm2 versus 1.7 ± 0.8 mm2) values compared to the control sites (P <0.05; paired t test).

Conclusion: BCP + rhPDGF‐BB might have the potential to support the initial stages of guided bone regeneration at chronic‐type lateral ridge defects.
Effect of Two Bioabsorbable Barrier Membranes on Bone Regeneration of Standardized Defects in Calvarial Bone: A Comparative Histomorphometric Study in Pigs
Authors: Bornstein Michael M. , Heynen Guy , Bosshardt Dieter D. , Buser Daniel
Published: August 2009

Background: The effect of two different bioabsorbable collagen membranes on bone regeneration was assessed in standardized, membrane‐protected calvarial defects in pigs.

Methods: Two standardized defect types (6 × 6 × 6 mm and 9 × 9 × 9 mm) were produced in the calvaria of pigs: empty defects without a membrane (group 1; eight defects per size); defects filled with deproteinized bovine bone mineral (DBBM) without a membrane (group 2; eight defects per size); defects filled with DBBM and covered by a collagen membrane (group 3; eight defects per size); and defects filled with DBBM and covered by a cross‐linked collagen membrane (CCM) (group 4; eight defects per size). Sacrifice took place 16 weeks after surgery, and the following parameters were analyzed: descriptive histology; semiquantitative histology (SQH), assessing bone regeneration in the whole defect area; and histomorphometric analysis of the percentage of bone and DBBM in the regenerated area at three different depth levels of the defect.

Results: Using SQH, both membrane types resulted in significantly better bone regeneration compared to groups 1 and 2, irrespective of the defect size (P <0.005), with no difference between the two membranes. In the histomorphometric analysis, the layer immediately below the surface exhibited a significantly higher percentage of bone in groups 3 (27%) and 4 (36%) versus the two other groups for the 9 × 9 × 9‐mm defects. No such differences were apparent for the 6 × 6 × 6‐mm defects or the other two depth levels (bottom and middle layer) for either defect size.

Conclusions: The two collagen membranes tested significantly enhanced bone regeneration, especially in the superficial level of the calvarial bone defects. The prototype CCM did not provide any further advantage in the present animal model.
Effect of Ridge Morphology on Guided Bone Regeneration Outcome: Conventional Tomographic Study
Authors: Park Sang‐Hoon , Brooks Sharon L. , Oh Tae‐Ju , Wang Hom‐Lay
Published: August 2009

Background: This study retrospectively analyzed conventional tomograms to estimate the prognostic value of the cross‐sectional ridge morphology on the clinical outcome of guided bone regeneration (GBR).

Methods: Presurgical conventional tomograms of 23 single‐implant sites were analyzed retrospectively in 20 patients. All sites had a non–space‐making buccal dehiscence defect associated with the subsequently placed dental implant. Simultaneous GBR procedures were performed, and 6‐month clinical outcomes were assessed. Measurements at baseline and at the 6‐month reentry included defect height (from smooth–rough junction to the most apical part of the defect) and horizontal bone gain at three locations (smooth–rough junction, middle, and most apical portion of the defect). All measurements were taken from a reference template. Tomographic parameters included the implant‐associated ridge angle and width measured at 6 mm below the alveolar crest and at the most apical point of the implant. Implant exposure and the presence of the barrier membrane were controlled for during statistical analyses.

Results: The presurgical ridge angle had a significant negative correlation with the percentage of defect height reduction (r = −0.621; P = 0.002) and horizontal bone gain (r = −0.469; P = 0.024). This difference remained significant even after controlling for implant/membrane exposure (P = 0.001 and P = 0.019, respectively). A statistically and clinically greater percentage of defect height reduction was observed for ridge angles <28° (P = 0.023). Ridge width did not have a significant effect on the regenerative outcome.

Conclusion: Cross‐sectional presurgical ridge angles may have prognostic value in estimating the outcome of simultaneous GBR.
Descriptive Analysis of Implant and Prosthodontic Survival Rates With Fixed Implant–Supported Rehabilitations in the Edentulous Maxilla
Authors: Lambert France E. , Weber Hans‐Peter , Susarla Srinivas M. , Belser Urs C. , Gallucci German O.
Published: August 2009

Background: This descriptive study reviewed the 1‐ to 15‐year survival rates of fixed implant rehabilitations in the edentulous maxilla.

Methods: An electronic search was conducted, and cohort studies with 1‐ to 15‐year follow‐ups were identified by two independent reviewers. The implant and prosthodontic survival rates were reviewed at 1‐, 3‐, 5‐, 10‐, and 15‐year endpoints. Descriptive analysis includes surface characteristics, bone‐augmentation procedure, prosthetic design, and implant number and distribution along the edentulous maxilla.

Results: Thirty‐three studies, including 1,320 patients and 8,376 implants, were selected for analysis. The overall calculated implant survival rates ranged from 94% (1 year) to 87.7% (15 years). The implant survival rates for rough‐surface implants ranged from 97% (1 year) to 98% (15 years); machined implants showed survival rates of 92% to 87.7%; respectively. Implants placed in native bone had greater survival rates than those placed in augmented bone. The prosthodontic survival rate ranged from 98.2% at 1 year to 92.1% at the 10‐year endpoint, and it was only influenced by the implant number and distribution.

Conclusions: Implants with rough surfaces showed a statistically higher survival rate than machined implants at all intervals. Implants placed in augmented bone had a statistically lower survival rate, except for rough‐surface implants, for which no statistical difference between augmented and non‐augmented bone survival rates was found. Machined implants showed a stable survival rate only when placed in native bone. When machined implants were placed in augmented bone, the survival rate decreased significantly at each study endpoint. The prosthetic design, veneering material, and the number of prostheses per arch had no influence on the prosthodontic survival rate. Implant number and distribution along the edentulous maxilla seemed to influence the prosthodontic survival rate.
Reaching the Top: Career Anchors and Professional Development in Nursing
Authors: Kaplan Ruth , Shmulevitz Carmela , Raviv Dennie
Published: August 2009

This study, based on Shein's conceptual theory of career anchors, examined the relationship between career anchors, professional development and emerging career patterns for graduates of 12 consecutive two year second career programs in nursing (N=231) compared to graduates of concurrent four year academic programs (N=273). A 2-group comparison design was used and data collection tools included a demographic profile, a professional profile and a career anchor questionnaire. Statistically significant differences were found in regard to career anchors (p< 0.001) and career development (p< 0.001). Primary career anchors for the second career nurses were specialization and lifestyle where academic graduates chose management, autonomy and service. Academics displayed a statistically significant preference for administrative specialization (34%) compared to the second career tract (6.5%). Researchers propose that each group develops differently and contributes to the workplace and the importance of both certification and academic incentives to ensure recruitment.
A Fixed Point Theorem and Equivariant Points for Set-valued Mappings
Authors: Shitanda Yoshimi
Published: August 2009

We give a proof of a coincidence theorem for a Vietoris mapping and a compact mapping and prove the Lefschetz fixed point theorem for the class of admissible mappings which contains upper semi-continuous acyclic mappings. When a source space is a paracompact Hausdorff space with a free involution and a target space is a closed topological manifold with an involution, the existence of equivariant points is proved for the class of admissible mappings under some conditions. When a source space is a Poincaré space with a finite covering dimension, the covering dimension of the set of equivariant points is determined.
Automorphisms of a Polynomial Ring Which Admit Reductions of Type I
Authors: Kuroda Shigeru
Published: August 2009

Recently, Shestakov-Umirbaev solved Nagata’s conjecture on an automorphism of a polynomial ring. To solve the conjecture, they defined notions called reductions of types I–IV for automorphisms of a polynomial ring. An automorphism admitting a reduction of type I was first found by Shestakov-Umirbaev. Using a computer, van den Essen–Makar-Limanov–Willems gave a family of such automorphisms. In this paper, we present a new construction of such automorphisms using locally nilpotent derivations. As a consequence, we discover that there exists an automorphism admitting a reduction of type I which satisfies some degree condition for each possible value.
Characterization of surfacing on exteriors and identification of pathologies in San Francisco de Paula (Pelotas/Rio Grande del Sud, Brasil)
Authors: Gonçalves Margarete R. F. , Oliveira Mário M.
Published: August 2009

San Francisco de Paula Cathedral, a nineteenth century neoclassical building, epitomizes the ballooning population and thriving economy that prevailed in Brazil at the time. Ever since its construction in 1813 under an initiative of Felício da Costa Pereira and donor Antonio Francisco de los Ángeles (Almanaque Pelotas, 1914; p. 176), it underwent enlargements, changes and remodelling. It acquired its present appearance in 1948, when the outside walls were surfaced with a blend of cement, sand and isinglass, locally known as “combed cement”. That surfacing is presently in the process of maintenance and restoration. In light of the scant and incipient literature on the subject, a study was conducted prior to rehabilitation to analyze the construction system used in the building, characterize the surfacing both physically and chemically, and identify visible pathologies.
THE ROLE OF BIOMEDICAL ENGINEERING PROFESSIONS IN MEDICAL EDUCATION
Authors: Aydın Serap
Published: August 2009

In the present study, the important role of biomedical engineering (BME) professions in medical education (ME) is highlighted. We propose that BME and ME should be integrated in a joint department to provide high-quality occupational education in medicine. Then, we illustrate the basic connections and close relations between BME and ME with respect to the universal subfields of each scientific branch. As this regard, the proposed joint department in medical faculty would guide the medicine to use innovative educational tools such as humanistic models, realistic simulations, video games, web-based online resources, etc. in both basic and clinical ME. In addition, the combination of two disciplines would prepare the initiative facilities for multidisciplinary original research studies improving human health. Moreover, new trends in instructional evaluation could be captured by studying together in teams.
KINEMATIC ANALYSIS AND 3D FINITE ELEMENT ANALYSIS OF A MOBILE-BEARING ARTIFICIAL HIGH FLEXION KNEE
Authors: Sivarasu Sudesh , Mathew Lazar
Published: August 2009

Total knee arthroplasty (TKA) has been the end-time surgical procedure for pain relief and movement restoration in cases of severe arthritis. The knee implant design plays a vital role in deciding the activity levels of a patient after total knee replacement (TKR). In about 90% of younger patients undergoing the knee replacement surgeries, the restriction is not from the subject but from the implant design. This paper discusses parameters affecting the activity levels after TKR. It also briefs the design aspects of a novel knee design that allows the normal high flexion activity even after TKR.

The application of finite element modeling in medical applications has been evolving as the field of high importance especially in the development of medical devices. The TKA has been in existence for over six decades till now. The generic artificial knee implants used in the TKA have the restriction in its range of motion of about 90°. A new design allowing flexion extension range of over 120° was designed with a view to facilitate partial squatting and the same is used for the analysis purpose. The loading conditions of 10 times the body weight are considered. The finite element analyses of the designs were carried out based on standard biomaterial used in orthopedic implants. In this paper, we have discussed the results of analyses of an artificial knee with titanium (Ti) alloy. The results of the analyses were used in identifying areas of extreme stresses within the design and the spot prone for higher deformation. Based on these results, slight modification on the designs was carried out. The results are also verified whether the body is within the linear deformation levels. As the results obtained were very satisfactory, the models have been recommended for prototyping.
PERFORMANCE ANALYSIS OF NONLINEAR TRANSFORMATIONAL ECG COMPRESSION METHOD
Authors: Aggarwal Vibha , Patterh Manjeet Singh
Published: August 2009

This paper presents and analyzes nonlinear transform-based method electrocardiogram (ECG) compression. The procedure used is similar to that used in linear transform-based method. The ECG signal is first transformed using (i) linear transform: discrete cosine transforms (DCT), Laplacian pyramid (LP), wavelet transform (WT) and it is transformed using (ii) nonlinear transform: essentially nonoscillatory cell average (ENOCA). The transformed coefficients (TC) are thresholded using the bisection algorithm in order to match the predefined user-specified percentage root mean square difference (PRD) within the tolerance. Then, the binary lookup table is made to store the position map for zero and nonzero coefficients (NZCs). The NZCs are quantized by Max–Lloyd quantizer followed by arithmetic coding. Lookup table is encoded by Huffman coding. The results are presented on different ECG signals of varying characteristics. The results show that nonlinear transform (ENOCA) gives better performance at high PRD where as at low PRD, DCT performs better.
LOWER LIMB JOINT POSITION SENSE IN PATIENTS WITH TYPE II DIABETES MELLITUS
Authors: Hsu Wei-Chun , Lu Tung-Wu , Liu Ming-Wei
Published: August 2009

Diabetes mellitus (DM), of which type II has been described as an international epidemic, is a major cause of death. Diabetic peripheral neuropathy (PN) is a condition secondary to hyperglycemia, where progressive loss of peripheral nerve function, including sensory and motor functions, occurs over time. Early detection of PN-related impairments may be helpful for the management of patients with DM. Among the methods for the evaluation of these impairments, only that for joint position sense (JPS) requires both motor and sensory involvement. The purpose of the current study was to compare the JPS of the lower limb joints in patients with no or mild diabetic PN to those of normal controls both during weight-bearing (WB) and non-weight-bearing (NWB) conditions using 3D motion analysis methods. The results supported the hypothesis that in well controlled diabetic patients with no or mild PN, JPS deficits can be found only at the ankle joint during WB conditions, resulting in overestimation of dorsiflexion angles. This suggests that at the very early stage of development of diabetic PN, distal joint involvement precedes that of proximal joints. Early detection of these changes, through the assessment of the JPS for all the lower limb joints under both NWB and WB conditions, will be helpful for the development of clinical preventive and treatment programs for patients with DM, even if their glucose level are well controlled. Gait and balance training in these patients should emphasize proprioception training exercises during WB conditions.
Imaging features of extraaxial musculoskeletal tuberculosis
Authors: Vanhoenacker Filip M , Sanghvi Darshana , De Backer Adelard
Published: August 2009

Tuberculosis (TB) continues to be a public health problem in both developing and industrialized countries. TB can involve pulmonary as well as extrapulmonary sites. The musculoskeletal system is involved in 1-3% of patients with tuberculosis. Although musculoskeletal TB has become uncommon in the Western world, it remains a huge problem in Asia, Africa, and many developing countries. Tuberculous spondylitis is the most common form of musculoskeletal TB and accounts for approximately 50% of cases. Extraspinal musculoskeletal TB shows a predilection for large joints (hip and knee) and para-articular areas; isolated soft tissue TB is extremely rare. Early diagnosis and prompt treatment are mandatory to prevent serious destruction of joints and skeletal deformity. However, due to the nonspecific and often indolent clinical presentation, the diagnosis may be delayed. Radiological assessment is often the first step in the diagnostic workup of patients with musculoskeletal TB and further investigations are decided by the findings on radiography. Both the radiologist and the clinician should be aware of the possibility of this diagnosis. In this manuscript we review the imaging features of extraspinal bone, joint, and soft tissue TB.
Vesicovaginal reflux: A case report
Authors: Warade Monali , Majid Yameen , Dayananda L , Gupta Kanchan
Published: August 2009

Vesicovaginal reflux is a common cause of urinary incontinence in girls. A micturating cystourethrogram, which is the diagnostic investigation of choice, can demonstrate retrograde filling of the vagina during micturition and the complete emptying of the vagina at the end of micturition. Vesicovaginal reflux is a rare cause of gross hydrocolpos occurring without any anatomical obstruction. The condition may be associated with functional voiding disturbances.
PET/CT guidance for percutaneous fine needle aspiration cytology/biopsy
Authors: Govindarajan MJ , Nagaraj KR , Kallur KG , Sridhar PS
Published: August 2009

PET/CT, used as a guiding tool, can improve the accuracy of percutaneous fine needle aspiration cytology (FNAC)/biopsy due to its ability to incorporate both physiological and anatomical information.
Case Report: Littoral cell angioma of spleen
Authors: Rana Netra , Ming Zhang , Hui Ma Shao , Bin Yan
Published: August 2009

Littoral cell angioma is a rare primary vascular neoplasm of the spleen, composed of littoral cells that line the splenic sinuses of the red pulp. It was thought to be a benign, incidental lesion. However, many recent reports have described it to be a malignant lesion with congenital and immunological associations. The definitive diagnosis can only be made after histology and immunohistochemistry studies.
Double fetus-in-fetu: CT scan diagnosis in an adult
Authors: Daga BV , Chaudhary VA , Ingle Amit S , Dhamangaokar Vinayak B , Jadhav Deepti P , Kulkarni Prasanna A
Published: August 2009

A fetus-in-fetu (FIF) is an uncommon developmental abnormality characterized by a reasonably well-formed but aborted fetus that is seen in the form of an encapsulated, pedunculated vertebrate tumor in the patient′s abdomen. We report an interesting case of a double FIF in a 20-year-old man, who presented with acute abdominal pain and a lump. CT scan of the abdomen revealed two ill-formed fetuses-in-fetu, which were seen as a 15-cm complex, encapsulated mass in the lower retroperitoneum; there was also free fluid in the abdomen. The diagnosis of a ruptured twin FIF was made. Complete surgical excision of the lesion was performed and the diagnosis was confirmed histopathologically. To the best of our knowledge, the CT scan findings of a ruptured double FIF in an adult have not been previously documented.
Reliability of Organic Field‐Effect Transistors
Authors: Sirringhaus Henning
Published: August 2009

In this article, we review current understanding of the reliability of organic field‐effect transistors, with a particular focus on degradation of device characteristics under bias stress conditions. We discuss the various factors that have been found to influence the operational stability of different material systems, including dependence on stress voltage and duty cycle, gate dielectric, environmental conditions, light exposure, and contact resistance. A key question concerns the role of extrinsic factors, such as oxidation or presence of moisture, and that of intrinsic factors, such as the inherent structural and electronic disorder that is present in thin organic semiconductor films. We also review current understanding of the microscopic defects that could play a role in charge trapping in organic semiconductors.
Anwendung von massiv paralleler Berechnung mit Grafikkarten (GPGPU) für CFD‐Methoden im Brandschutz
Authors: Belaschk Hendrik C. , Münch Matthias
Published: August 2009

Der Einsatz von Brandsimulationsprogrammen, die auf den Methoden der Computational Fluid Dynamics (CFD) beruhen, wird in der Praxis immer breiter. Infolge der Zunahme von verfügbarer Rechenleistung in der Computertechnik können heute die Auswirkungen möglicher Brandszenarien nachgebildet und daraus nützliche Informationen für den Anwendungsfall gewonnen werden (z. B. Nachweis der Zuverlässigkeit von Brandschutzkonzepten). Trotz der erzielten Fortschritte reicht die Leistung von heute verfügbaren Computern bei weitem nicht aus, um einen Gebäudebrand mit allen beteiligten physikalischen und chemischen Prozessen mit der höchstmöglichen Genauigkeit zu simulieren. Die in den Computerprogrammen zur Berechnung der Brand‐ und Rauchausbreitung implementierten Modelle stellen daher immer einen Kompromiss zwischen der praktischen Recheneffizienz und dem Detailgrad der Modellierung dar. Im folgenden Aufsatz wird gezeigt, worin die Ursachen für den hohen Rechenbedarf der CFD‐Methoden liegen und welche Problemstellungen und möglichen Fehlerquellen sich aus den getroffenen Modellvereinfachungen für den Ingenieur ergeben. Darüber hinaus wird ein neuer Technologieansatz vorgestellt, der die Rechenleistung eines Personalcomputers unter Verwendung spezieller Software und handelsüblicher 3D‐Grafikkarten massiv erhöht. Hierzu wird am Beispiel des Fire Dynamics Simulator (FDS) demonstriert, dass sich die erforderliche Berechnungszeit für eine Brandsimulation auf einem Personalcomputer um den Faktor 20 und mehr verringern lässt.

Application of general‐purpose computing on graphics processing units (GPGPU) in CFD techniques for fire safety simulations.

The use of fire simulation programs based on computational fluid dynamics (CFD) techniques is becoming more and more widespread in practice. The increase in available computing power enables the effects of possible fire scenarios to be modelled in order to derive useful information for practical applications (e.g. analysis of the reliability of fire protection concepts). However, despite the progress in computing power the performance of currently available computers is inadequate for simulating a building fire including all relevant physical and chemical processes with maximum accuracy. The models for calculating the spread of fire and smoke implemented in the computer programs therefore always represent a compromise between practical computing efficiency and level of modelling detail. This paper illustrates the reasons for the high computing power demand of CFD techniques and describes potential problems and sources of error resulting from simplifications applied in the models. In addition, the paper presents a new technology approach that significantly increases the computing power of a PC using special software and standard 3D graphics cards. The Fire Dynamics Simulator (FDS) is used as an example to demonstrate how the required calculation time for a fire simulation on a PC can be reduced by a factor of 20 and more.