bluuebunny/crossref_metadata_2025 huggingface dataset:
Five‐year results of a randomized controlled clinical trial comparing zirconia and titanium abutments supporting single‐implant crowns in canine and posterior regions
Authors: Zembic Anja , Bösch Adrian , Jung Ronald E. , Hämmerle Christoph H. F. , Sailer Irena
Published: October 2012

Objectives

To test the survival rates, and the technical and biological complication rates of customized zirconia and titanium abutments 5 years after crown insertion.

Material and methods

Twenty‐two patients with 40 single implants in maxillary and mandibular canine and posterior regions were included. The implant sites were randomly assigned to zirconia abutments supporting all‐ceramic crowns or titanium abutments supporting metal‐ceramic crowns. Clinical examinations were performed at baseline, and at 6, 12, 36 and 60 months of follow‐up. The abutments and reconstructions were examined for technical and/or biological complications. Probing pocket depth (PPD), plaque control record (PCR) and Bleeding on Probing (BOP) were assessed at abutments (test) and analogous contralateral teeth (control). Radiographs of the implants revealed the bone level (BL) on mesial (mBL) and distal sides (dBL). Data were statistically analyzed with nonparametric mixed models provided by Brunner and Langer and STATA (P < 0.05).

Results

Eighteen patients with 18 zirconia and 10 titanium abutments were available at a mean follow‐up of 5.6 years (range 4.5–6.3 years). No abutment fracture or loss of a reconstruction occurred. Hence, the survival rate was 100% for both. Survival of implants supporting zirconia abutments was 88.9% and 90% for implants supporting titanium abutments. Chipping of the veneering ceramic occurred at three metal‐ceramic crowns supported by titanium abutments. No significant differences were found at the zirconia and titanium abutments for PPD (meanPPDZrO23.3 ± 0.6 mm, mPPDTi3.6 ± 1.1 mm), PCR (mPCRZrO20.1 ± 0.3, mPCRTi0.3 ± 0.2) and BOP (mBOPZrO20.5 ± 0.3, mBOPTi0.6 ± 0.3). Moreover, the BL was similar at implants supporting zirconia and titanium abutments (mBLZrO21.8 ± 0.5, dBLZrO22.0 ± 0.8; mBLTi2.0 ± 0.8, dBLTi1.9 ± 0.8).

Conclusions

There were no statistically or clinically relevant differences between the 5‐year survival rates, and the technical and biological complication rates of zirconia and titanium abutments in posterior regions.
CD1d‐dependent, iNKT‐cell cytotoxicity against keratinocytes in allergic contact dermatitis
Authors: Balato Anna , Zhao Yuming , Harberts Erin , Groleau Patricia , Liu Juan , Fishelevich Rita , Gaspari Anthony A.
Published: September 2012

Conventional CD8+ T‐lymphocytes are thought to be major effector cells in allergic contact dermatitis (ACD). However, previous work has demonstrated a significant population of invariant natural killer T‐cells (iNKT‐cells) in the elicitation phase of ACD. In this study, we investigate whether iNKT‐cells have the capacity to serve as effector lymphocytes in ACD. Using in situ staining of skin biopsy specimens from ACD lesions, we observed intra‐epidermal iNKT‐cells. Presence of these cells provides the possibility of interactions with keratinocytes (KC), Langerhans cells (LC) and CD1d‐bearing antigen‐presenting cells (APC). Investigation into gene expression profiles of cytotoxic effector molecules in seven different cases of ACD found that the expression of perforin and granzymes A, B and K were significantly elevated in ACD relative to paired clinically normal skin. Immunostaining of ACD skin biopsy specimens revealed that these cytotoxic granules indeed localized to iNKT‐cells. Studies of antigen presentation of KC to iNKT‐cells show that these epithelial cells do not activate the expression of cytotoxicity effector genes in resting iNKT‐cells, but had the capacity to serve as targets for activated iNKT‐cells, which was dependent on CD1d expression. Mature LC were not able to present glycolipids to iNKT‐cells and did not up‐regulate CD1d in vitro to a variety of maturational stimuli or in vivo during ACD. These data suggest that iNKT‐cells can serve as effector cells during human ACD and provide the rationale for developing inhibitory glycolipids as therapeutic agents for ACD.
Strong induction of AIM2 expression in human epidermis in acute and chronic inflammatory skin conditions
Authors: de Koning Heleen D. , Bergboer Judith G.M. , van den Bogaard Ellen H. , van Vlijmen‐Willems Ivonne M.J.J. , Rodijk‐Olthuis Diana , Simon Anna , Zeeuwen Patrick L.J.M. , Schalkwijk Joost
Published: September 2012

Absent in melanoma 2 (AIM2) is a double‐stranded DNA receptor, and its activation initiates an interleukin‐1 beta processing inflammasome. AIM2 is implicated in host defense against several pathogens, but could hypothetically also contribute to autoinflammatory or autoimmune diseases, such as is the case for NLRP3. Using thoroughly characterised antibodies, we analysed AIM2 expression in human tissues and primary cells. A strong epidermal upregulation of AIM2 protein expression was observed in several acute and chronic inflammatory skin disorders, such as psoriasis, atopic dermatitis, venous ulcera, contact dermatitis, and experimental wounds. We also found AIM2 induction by interferon‐gamma in submerged and three‐dimensional in vitro models of human epidermis. Our data highlight the dynamics of epidermal AIM2 expression, showing Langerhans cell and melanocyte‐restricted expression in normal epidermis but a pronounced induction in subpopulations of epidermal keratinocytes under inflammatory conditions.
Glacier melting and stoichiometric implications for lake community structure: zooplankton species distributions across a natural light gradient
Authors: Laspoumaderes Cecilia , Modenutti Beatriz , Souza María Sol , Bastidas Navarro Marcela , Cuassolo Florencia , Balseiro Esteban
Published: September 2012

Glaciers around the globe are melting rapidly, threatening the receiving environments of the world's fresh water reservoirs with significant changes. The meltwater, carried by rivers, contains large amounts of suspended sediment particles, producing longitudinal gradients in the receiving lakes. These gradients may result in changes in the light : nutrient ratio that affect grazer performance by altering elemental food quality. Thus, glacial melting may induce a shift in the phytoplankton carbon : nutrient ratio and hence influence the dominance of herbivorous zooplankton through stoichiometric mechanisms. To test this hypothesis, we combined field and experimental data, taking advantage of a natural light intensity gradient caused by glacial clay input in a deep oligotrophic Patagonian lake. Across this gradient, we evaluated the abundances of two consumer taxa with different phosphorus requirements, the copepod Boeckella gracilipes and the cladoceran Daphnia commutata, using a six‐station transect along the lake. We found significant differences in light : nutrient ratio and stoichiometric food quality of the seston, together with a switch from dominance of P‐rich Daphnia in low carbon : nutrient stations to dominance of low‐P copepods in high carbon : nutrient stations. The laboratory experiments confirmed that the difference in the carbon : nutrient ratio across the gradient is sufficient to impair Daphnia growth. The overall patterns are consistent with our prediction that shifts in the environmental light : nutrient ratio as a result of glacial melting would contribute to shifts in the dominance of stoichiometrically contrasting taxa in consumer guilds.
Range margin shifts of birds revisited – the role of spatiotemporally varying survey effort
Authors: Kujala Heini , Vepsäläinen Ville , Zuckerberg Benjamin , Brommer Jon E.
Published: September 2012

Global climate warming is predicted to lead to global and regional changes in the distribution of organisms. One influential approach to test this prediction using temporally repeated mapping surveys of organisms was suggested in a seminal paper by Thomas & Lennon (1999, Nature). The Thomas & Lennon approach corrects observed changes in the range margin for changes in the range size, and thus potentially controls for other broad‐scale environmental changes between surveys, however the approach does not necessarily account for potential biases in sampling effort. To verify whether the issue of variation in sampling effort affects empirical estimates of shifts in range margin, we reanalyzed all three published studies exploring range margin changes of breeding birds in Great Britain (GB), Finland, and New York State (NY). Accounting for changes in survey effort on range margins lowered the estimated shift for breeding birds in New York, but the shift remained statistically significant. For Great Britain and Finland, for which no direct estimate of survey effort is available, we used species richness (a strong correlate of survey effort in New York) as a proxy and found that in both cases the estimated shift in range margin was significantly reduced and became nonsignificant. To understand how robust the approach is to sampling biases, we use a simulation model to show that the Thomas & Lennon approach is, under certain conditions, sensitive to changes in detection probability (probability to detect true occupancy) which in turn may be affected by changes in surveying effort between surveys. We thus found evidence that temporal changes in the distribution of breeding birds based on repeated mapping surveys may be inflated by changes in survey effort along range boundaries. We discuss possible approaches to deal with this issue in the analysis and design of national or regional surveys.
Impacts of 3 years of elevated atmospheric CO2 on rhizosphere carbon flow and microbial community dynamics
Authors: Drigo Barbara , Kowalchuk George A. , Knapp Brigitte A. , Pijl Agata S. , Boschker Henricus T. S. , van Veen Johannes A.
Published: September 2012

Carbon (C) uptake by terrestrial ecosystems represents an important option for partially mitigating anthropogenic CO2 emissions. Short‐term atmospheric elevated CO2 exposure has been shown to create major shifts in C flow routes and diversity of the active soil‐borne microbial community. Long‐term increases in CO2 have been hypothesized to have subtle effects due to the potential adaptation of soil microorganism to the increased flow of organic C. Here, we studied the effects of prolonged elevated atmospheric CO2 exposure on microbial C flow and microbial communities in the rhizosphere. Carex arenaria (a nonmycorrhizal plant species) and Festuca rubra (a mycorrhizal plant species) were grown at defined atmospheric conditions differing in CO2 concentration (350 and 700 ppm) for 3 years. During this period, C flow was assessed repeatedly (after 6 months, 1, 2, and 3 years) by 13C pulse‐chase experiments, and label was tracked through the rhizosphere bacterial, general fungal, and arbuscular mycorrhizal fungal (AMF) communities. Fatty acid biomarker analyses and RNA‐stable isotope probing (RNA‐SIP), in combination with real‐time PCR and PCR‐DGGE, were used to examine microbial community dynamics and abundance. Throughout the experiment the influence of elevated CO2 was highly plant dependent, with the mycorrhizal plant exerting a greater influence on both bacterial and fungal communities. Biomarker data confirmed that rhizodeposited C was first processed by AMF and subsequently transferred to bacterial and fungal communities in the rhizosphere soil. Over the course of 3 years, elevated CO2 caused a continuous increase in the 13C enrichment retained in AMF and an increasing delay in the transfer of C to the bacterial community. These results show that, not only do elevated atmospheric CO2 conditions induce changes in rhizosphere C flow and dynamics but also continue to develop over multiple seasons, thereby affecting terrestrial ecosystems C utilization processes.
Do the maximum sizes, ages and patterns of growth of three reef‐dwelling labrid species at two latitudes differ in a manner conforming to the metabolic theory of ecology?
Authors: Lek E. , Fairclough D. V. , Hall N. G. , Hesp S. A. , Potter I. C.
Published: September 2012

The size and age data and patterns of growth of three abundant, reef‐dwelling and protogynous labrid species (Coris auricularis, Notolabrus parilus and Ophthalmolepis lineolata) in waters off Perth at c. 32° S and in the warmer waters of the Jurien Bay Marine Park (JBMP) at c. 30° S on the lower west coast of Australia are compared. Using data for the top 10% of values and a randomization procedure, the maximum total length (LT) and mass of each species and the maximum age of the first two species were estimated to be significantly greater off Perth than in the JBMP (all P < 0·001) and the maximum ages of O. lineolata in the two localities did not differ significantly (P > 0·05). These latitudinal trends, thus, typically conform to those frequently exhibited by fish species and the predictions of the metabolic theory of ecology (MTE). While, in terms of mass, the instantaneous growth rates of each species were similar at both latitudes during early life, they were greater at the higher latitude throughout the remainder and thus much of life, which is broadly consistent with the MTE. When expressed in terms of LT, however, instantaneous growth rates did not exhibit consistent latitudinal trends across all three species. The above trends with mass, together with those for reproductive variables, demonstrate that a greater amount of energy is directed into somatic growth and gonadal development by each of these species at the higher latitude. The consistency of the direction of the latitudinal trends for maximum body size and age and pattern of growth across all three species implies that each species is responding in a similar manner to differences between the environmental characteristics, such as temperature, at those two latitudes. The individual maximum LT, mass and age and pattern of growth of O. lineolata at a higher and thus cooler latitude on the eastern Australian coast are consistent with the latitudinal trends exhibited by those characteristics for this species in the two western Australian localities. The implications of using mass rather than length as the indicator variable when comparing the maximum sizes of the three species and the trends exhibited by the instantaneous growth rates of those species at different latitudes are explored. Although growth curves fitted to both the LT and masses at age for the males of each species lay above those for their females, this would not have influenced the conclusions drawn from common curves for both sexes.
The interaction between maternal stress and the ontogeny of the innate immune system during teleost embryogenesis: implications for aquaculture practice
Authors: Li M. , Leatherland J. F.
Published: September 2012

The barrier defences and acellular innate immune proteins play critical roles during the early‐stage fish embryos prior to the development of functional organ systems. The innate immune proteins in the yolk of embryos are of maternal origin. Maternal stress affects the maternal‐to‐embryo transfer of these proteins and, therefore, environmental stressors may change the course of embryo development, including embryonic immunocompetency, via their deleterious effect on maternal physiology. This review focuses on the associations that exist between maternal stress, maternal endocrine disturbance and the responses of the acellular innate immune proteins of early‐stage fish embryos. Early‐stage teleostean embryos are dependent upon the adult female for the formation of the zona pellucida as an essential barrier defence, for their supply of nutrients, and for the innate immunity proteins and antibodies that are transferred from the maternal circulation to the oocytes; maternally derived hormones are also transferred, some of which (such as cortisol) are known to exert a suppressive action on some aspects of the immune defences. This review summarizes what is known about the effects of oocyte cortisol content on the immune system components in early embryos. The review also examines recent evidence that embryonic cells during early cleavage have the capacity to respond to increased maternal cortisol transfer; this emphasizes the importance of maternal and early immune competence on the later life of fishes, both in the wild and in intensive culture.
Gender differences in the presence of drugs in violent deaths
Authors: Sheehan Connor M. , Rogers Richard G. , Williams George W. , Boardman Jason D.
Published: September 2012

Aims

To investigate differences in the presence of drugs, by gender, when considering deaths attributable to homicides and suicides.

Design

Logistic regression analysis of mortality data collected by the Colorado Violent Death Reporting System.

Participants and setting

A total of 5791 Colorado decedents who died of violent causes from 2004 to 2009.

Measurement

Forensic pathologist autopsy data on drug presence at time of death, coded as present, not present or missing.

Findings

Postmortem presence of drugs is associated strongly with the specific cause of violent death. Compared with suicide decedents, homicide decedents are significantly more likely to test positive for amphetamines [odds ratio (OR): 1.79; confidence interval (CI): 1.34, 2.39], marijuana (OR: 2.03; CI: 1.60, 2.58) and cocaine (OR: 2.60; CI: 2.04, 3.31), and are less likely to test positive for opiates (OR: 0.27; CI: 0.18, 0.39) and antidepressants (OR: 0.17; CI: 0.10, 0.28). When other drugs are controlled for the influence of alcohol is abated dramatically. The patterns of drug prevalence associated with homicide (particularly marijuana) are stronger among males; the patterns of drug prevalence associated with suicide are stronger among females.

Conclusions

Suicide and homicide decedents are characterized by varying patterns of licit and illicit drug use that differ by gender. Drugs associated with homicide (marijuana, cocaine and amphetamines) are stronger among males, while drugs associated with suicide are stronger among females (antidepressants and opiates). Taking these differences into consideration may allow for targeted interventions to reduce violent deaths.
Decreased microRNA(miR)-145 and increased miR-224 expression in T cells from patients with systemic lupus erythematosus involved in lupus immunopathogenesis
Authors: Lu M-C , Lai N-S , Chen H-C , Yu H-C , Huang K-Y , Tung C-H , Huang H-B , Yu C-L
Published: September 2012

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with abnormal T cell immune responses. We hypothesized that aberrant expression of microRNAs (miRNAs) in T cells may contribute to the pathogenesis of SLE. First, we analysed the expression profiles of 270 human miRNAs in T cells from five SLE patients and five healthy controls and then validated those potentially aberrant-expressed miRNAs using real-time polymerase chain reaction (PCR). Then, the expression of mRNAs regulated by these aberrant-expressed miRNAs was detected using real-time PCR. Finally, miRNA transfection into Jurkat T cells was conducted for confirming further the biological functions of these miRNAs. The initial analysis indicated that seven miRNAs, including miR-145, miR-224, miR-513-5p, miR-150, miR-516a-5p, miR-483-5p and miR-629, were found to be potentially abnormally expressed in SLE T cells. After validation, under-expressed miR-145 and over-expressed miR-224 were noted. We further found that STAT1 mRNA targeted by miR-145 was over-expressed and apoptosis inhibitory protein 5 (API5) mRNA targeted by miR-224 was under-expressed in SLE T cells. Transfection of Jurkat cells with miR-145 suppressed STAT1 and miR-224 transfection suppressed API5 protein expression. Over-expression of miR-224 facilitates activation-induced cell death in Jurkat cells. In the clinical setting, the increased transcript levels of STAT1 were associated significantly with lupus nephritis. In conclusion, we first demonstrated that miR-145 and miR-224 were expressed aberrantly in SLE T cells that modulated the protein expression of their target genes, STAT1 and API5, respectively. These miRNA aberrations accelerated T cell activation-induced cell death by suppressing API5 expression and associated with lupus nephritis by enhancing signal transducer and activator of transcription-1 (STAT)-1 expression in patients with SLE.
Hummingbird color preference within a natural hybrid population of Mimulus aurantiacus (Phrymaceae)
Authors: Handelman Corinne , Kohn Joshua R.
Published: September 2012

Hummingbird flowers are typically red in color but the reasons for this are not well understood. Relatively few studies have examined hummingbird flower color preferences under natural conditions in which flower color varies within a species. We recorded hummingbird visitation rates to flowers that vary in color from yellow to red in a natural hybrid population between red‐ and yellow‐flowered Mimulus aurantiacus subspecies. We also examined whether there were any correlations between color and flower size or nectar content. Finally, we reviewed the literature on hummingbird color choice tests using feeders and flowers. There were no correlations in this population between flower color and flower size, nectar volume, or sugar concentration. Nevertheless, hummingbirds undervisited the two most yellow color classes, overvisited orange flowers, and visited the two most red color classes in proportion to their frequency in the population. While Hummingbirds preferred flowers expressing red pigments to those that did not, the flowers with the most red hue were not the most attractive, as has been observed in similar studies with other species of Mimulus. While feeder studies generally fail to show hummingbird preference for red, all studies using flowers, including those that control all floral traits other than color, find consistent preference for red. Experiments are suggested that might help disentangle hypotheses for why hummingbirds exhibit this preference.
Survey of UK speech and language therapists’ assessment and treatment practices for people with progressive dysarthria
Authors: Collis Jessica , Bloch Steven
Published: September 2012

Background: Dysarthria knowledge is predominantly impairment‐based. As a result, speech and language therapists (SLTs) have traditionally adopted impairment‐focused management practices. However, guidance for best practice suggests that SLTs should consider the client holistically, including the impact of dysarthria beyond the impairment.

Aims: To investigate the current assessment and treatment practices used by UK SLTs with clients with progressive dysarthria and to identify whether these satisfy the needs of SLTs in their everyday practice. To investigate the extent to which they consider oromotor abilities, intelligibility, functional communication, participation and interaction to be important regarding assessment and treatment decisions. To explore whether management decisions are affected by level of clinical experience or settings in which SLTs work.

Methods & Procedures: An online survey of UK SLTs working with adults with progressive dysarthria.

Outcomes & Results: A total of 119 SLTs completed the survey. Respondents considered that targeting the levels of impairment, activity and participation are important in the management of clients with progressive dysarthria, as recommended by clinical guidelines and recent research. However a particularly high proportion of respondents reported the use of impairment‐based assessments. Respondents reported lacking the necessary tools to target interaction in assessment and intervention. The intervention that respondents use with clients varies according to the progressive disorder and dysarthria severity. There is evidence for a trend that less experienced SLTs and those working predominantly in hospital‐based settings focus on the impairment, whereas more SLTs with more experience and those based in predominantly community‐based settings look beyond the impairment.

Conclusions & Implications: The values held by SLTs match guideline recommendations for best practice, however the clinical reality is that the assessment of progressive dysarthria remains predominantly impairment‐focused. New tools need to be developed and integrated into practice to target interaction in assessment and intervention, to reduce the gap between best practice recommendations and clinical reality. Ongoing research into the effectiveness of SLT intervention with clients with progressive dysarthria is required to guide clinical management decisions.
Phonological and phonetic marking of information status in Foreign Accent Syndrome
Authors: Kuschmann Anja , Lowit Anja
Published: September 2012

Background:Foreign Accent Syndrome (FAS) is a motor speech disorder in which a variety of segmental and suprasegmental errors lead to the perception of a new accent in speech. Whilst changes in intonation have been identified to contribute considerably to the perceived alteration in accent, research has rarely focused on how these changes impact on the pragmatic use of intonation. However, a greater understanding of the role of intonational changes in FAS and its impact on the functional use of intonation is fundamental to developing appropriate assessment and subsequently treatment strategies for FAS.

Aims:This study investigated intonation patterns in speakers with FAS and matched control participants with regard to their ability to signal new and given information (information status) within sentences. A phonetic and phonological perspective was taken with the aim of identifying the characteristics that were compromised in FAS to convey this linguistic function.

Methods & Procedures:Four speakers with FAS and four control participants participated in the speech production experiment. The speech data were assessed perceptually, and examined in relation to the use of the phonetic parameters fundamental frequency (f0), intensity and duration as well as phonological categories, i.e. pitch accents and de‐accentuation, using the autosegmental–metrical (AM) framework of intonational analysis.

Outcomes & Results:Both speaker groups employed all three phonetic parameters to differentiate between new and given information. However, groups differed regarding the use of phonological markers, with speakers with FAS frequently placing pitch accents on given information instead of de‐accenting these elements. According to the perceptual evaluation, three of the four speakers with FAS had problems signalling information status.

Conclusions & Implications: The fact that speakers with FAS marked information status similarly to control speakers at the phonetic level, but failed to do so using phonological categories highlights the importance of assessing phonetic as well as phonological features to gain detailed information about the functional use of intonation in FAS.
Arginase enzymes in the human prostate: expression of arginase isoenzymes and effects of arginase inhibitors on isolated human prostate tissue
Authors: Kedia George T. , Sonnenberg Joachim E. , Kuczyk Markus A. , Ückert Stefan
Published: September 2012

What's known on the subject? and What does the study add?

A previous study by Lexander et al. in 2005, using two‐dimensional gel electrophoresis, demonstrated the expression of arginase type II in the different anatomical regions of the prostate; however, to date, no study has addressed, using an in vitro approach, the role of arginase isoenzymes in the human prostate.

The results of the present study demonstrate that: both arginase isoenzymes, Arg I and Arg II, are expressed in the transition zone of the human prostate; the inhibition of arginase antagonized, to a certain degree, the tension brought about by noradrenaline in isolated human prostate tissue; exposure of human prostate tissue to arginase inhibitors enhanced the local production of cyclic GMP; and inhibition of arginase enzymes in the human prostate may augment the activity of the nitric oxide/cyclicGMP pathway.

OBJECTIVE

To investigate the expression of arginase isoenzymes type I (Arg I) and type II (Arg II) in the transition zone of the human prostate and the functional significance of arginase enzymes in the control of prostate smooth muscle.

MATERIALS AND METHODS

Human prostate tissue was obtained from male patients who had undergone pelvic surgery.

The expression of Arg I and Arg II was investigated using Western blot analysis.

Using the organ bath technique, the effects of cumulative administration of difluoromethylornithine (DFMO), H‐Orn‐OH × HCl, H‐Ile‐OH and N‐ω‐hydroxy‐nor‐L‐arginine (nor‐NOHA; 1 nM–10 µM) on the tension induced by noradrenaline in isolated prostate tissue were assessed.

Tissue strips were also exposed to arginase inhibitors and the production of cyclic GMP was determined.

RESULTS

Western blot analysis showed the expression of Arg I and Arg II in the transition zone of the prostate.

The tension induced by noradrenaline was antagonized by the drugs in the following rank order of efficacy: H‐Orn‐OH × HCl ≥ H‐Ile‐OH ≥ DFMO > nor‐NOHA; however, the maximum reversion of tension recorded ranged from only −25 to −13%.

The enhancement in cyclic GMP production registered in the presence of the arginase inhibitors ranged from four‐ to 14‐fold.

CONCLUSIONS

Arg I and Arg II are expressed in the transition zone of the human prostate.

Isometric tension studies and measurement of cyclic GMP showed that inhibition of arginase can reverse, to a certain degree, the tension of human prostate tissue induced by the activation of α‐adrenoceptors and enhance the accumulation of cyclic GMP.

Future studies should explore further the role of arginase enzymes in the relaxation mediated by nitric oxide in prostate smooth muscle.
Numerical Modeling of Dynamic Behavior of Annular Tuned Liquid Dampers for Applications in Wind Towers
Authors: Ghaemmaghami Amirreza , Kianoush Reza , Yuan Xian‐Xun
Published: September 2012

Abstract:  In this study, the performance of annular liquid tanks as a tuned liquid damper (TLD) in mitigating the vibration of wind turbines was investigated using a numerical model. A proposed hybrid wind tower model composed of a concrete shaft and a steel mast with a height of 150 m was simulated using a single‐degree‐of‐freedom system. The structural domain including the tank wall and a rigid mass was modeled using finite element method, while the fluid domain was simulated by finite volume method using CFX software. A parametric study was carried out to investigate the behavior of annular TLD under harmonic loads for different mass and frequency ratios as well as displacement amplitudes. The damping characteristics of the annular TLD model were derived by comparing the numerical results with an equivalent linear model. In addition, the effectiveness of annular TLD was estimated by comparing the numerically calculated damping ratios with those corresponding to the optimum damping ratio values derived for a particular mass ratio based on the concept of tuned mass damper. It was found that that the annular TLD is effective when the amplitude of excitation is small. Moreover, the response of TLD in terms of nonlinear free surface sloshing and the energy dissipated by the system was discussed. Finally, the effectiveness of annular TLD in reducing the structural response of wind turbine towers under random vibrations was evaluated and discussed.
Population Density, House Prices and Mortgage Design
Authors: Miles David
Published: October 2012

Whether house prices rise faster or slower than average incomes affects the level of home ownership and the riskiness of different means of financing house purchase. This study develops a model of the housing market with the property that the major determinant of house price rises relative to incomes is the evolution of population density. The model implies that if population density is on an upward trajectory, rises in population and in incomes increasingly generate price responses and diminishing rises in the stock of housing. Rises in population density make high and rising levels of house prices likely; this makes alternatives to standard debt financing of home ownership become more desirable. The impact this has on the structure of risk‐sharing contracts between providers of outside equity and homeowners is analysed.
Prog Imperfective Drift in Ancient Greek? ReconsideringEimi‘Be’ with Present Participle1
Authors: Bentein Klaas
Published: September 2012

In this article, I reconsider the diachrony of the Ancient Greek periphrastic construction ofeimi‘I am’ with present participle by means of Bertinetto’s recently proposed model for the development of progressive grammatical morphemes (grams) (a process called ‘progimperfective drift’). While Bertinetto’s proposal sheds new light on the diachronic development of the construction, at the same time the evidence from Ancient Greek brings to light the need for modification and further refinement of the model (most importantly with regard to the role of what I call the ‘stative’ aspectual function, next to the diachronic source(s) of the construction). I furthermore show thateimi‘I am’ with present participle never fully developed a (focalised) progressive function, which can be explained in terms of ‘constructional competition.’
LIQUIDITY RISK, CREDIT RISK AND THE OVERNIGHT INTEREST RATE SPREAD: A STOCHASTIC VOLATILITY MODELLING APPROACH*
Authors: BEIRNE JOHN , CAPORALE GUGLIELMO MARIA , SPAGNOLO NICOLA
Published: September 2012

In this paper we model the volatility of the spread between the overnight interest rate and the central bank policy rate (the policy spread) for the euro area and the UK during the two main phases of the financial crisis that began in late 2007. We find a strong role played by liquidity risk volatility, but also private bank credit risk volatility after the collapse of Lehman Brothers. The main implication is that, in crisis times, a sufficiently flexible operational framework for monetary policy implementation produces the most timely response to market tensions.
Reclaiming Degraded Rainforest: A Spatial Evaluation of Gains and Losses in Subtropical Eastern Australia to Inform Future Investment in Restoration
Authors: Shoo Luke P. , Scarth Peter , Schmidt Susanne , Wilson Kerrie A.
Published: September 2012

Forest restoration is expected to play a pivotal role in reducing extinctions driven by deforestation and climate change over the next century. However, spatial and temporal patterns of restoration (both passive and active) are likely to be highly variable depending on degree of land use change as well as levels of forest and soil degradation and residual vegetation. Uncertainties regarding the spatial and temporal reinstatement of forest on degraded land make it difficult to determine where future investment in active restoration should be targeted. We used satellite data to quantify change in the extent and foliage projection cover (FPC) of woody vegetation returning to land previously cleared of subtropical rainforest in eastern Australia. We show a modest recovery of woody vegetation but document high variability in this trend between local areas, expanding by over 5% in some situations but declining by up to 2% in others over the last decade (1999–2009 period). This was accompanied by minor change in average FPC (−0.2 to 4.2%). Overall, decadal expansion in woody vegetation was most apparent in local areas with intermediate levels of existing forest reestablishment and was most likely to occur on steep terrain near existing vegetation. These results provide a valuable first evaluation of where restoration is occurring and the likely time frame required to meet conservation objectives under a business as usual scenario. This knowledge enables returns from current investment to be quantified and can be used to better allocate funds for restoration in the future.
Antiepileptic drugs and the fetal epigenome
Authors: Emes Richard D. , Clifford Harry , Haworth Kim E. , Farrell William E. , Fryer Anthony A. , Carroll William D. , Ismail Khaled M. K.
Published: September 2012

Antiepileptic drugs (AEDs) can lower maternal folate and increase maternal homocysteine levels, which are known to affect the methyl cycle and hence DNA methylation levels. The influence of in utero exposure to AEDs on fetal DNA methylation was investigated. Genome‐wide fetal epigenomic profiles were determined using the Infinium 27K BeadArray from Illumina (San Diego, CA, U.S.A.). The Infinium array measures approximately 27,000 CpG loci associated with 14,496 genes at single‐nucleotide resolution. Eighteen cord blood samples (nine samples from babies exposed to AEDs and nine controls) from otherwise uncomplicated pregnancies were compared. Unsupervised hierarchic clustering was used to compare the calculated methylation profiles. A clear distinction between the methylation profiles of samples from babies exposed to AEDs in utero compared with controls was detected. These data provide evidence of an epigenetic effect associated with antenatal AED and high‐dose folate supplementation during pregnancy. The differences in fetal DNA methylation of those exposed to AEDs shows that a genome‐wide effect of methylation is evident. In addition, the epigenetic changes observed appear to be, in this limited sample, independent of extremes of birth weight centiles. These preliminary data highlight possible mechanisms by which AEDs might influence fetal outcomes and the potential of optimizing AED‐specific folate supplementation regimens to offset these effects.
Do plant functional traits determine spatial pattern? A test on species‐rich shrublands, Western Australia
Authors: Perry George L.W. , Enright Neal J. , Miller Ben P. , Lamont Byron B.
Published: September 2012

Questions

A species' spatial pattern is the outcome of a series of filters: demographic, disturbance, environmental and functional, all varying over space and time. To evaluate the importance of function as a filter we ask: (1) do a species' functional traits allow prediction of its fine‐scale spatial patterning, and (2) how consistent is the fine‐scale spatial pattern shown by the same species across multiple sites where the properties of the other filters may vary?

Location

Species‐rich Mediterranean climate shrublands of southwestern Australia's northern sandplains.

Methods

Using fully mapped plots at four sites (each >10 000 individuals, 74–112 species), we characterized individual species spatial patterning using point pattern analyses. We classified species spatial patterns in three ways: (1) whether they departed from a null model controlling for first‐order effects (i.e. are they aggregated?), (2) parameterization of Thomas cluster processes (what form does any clustering take?), and (3) their position in a multivariate ‘pattern space’ (do species show different types of pattern?). We then explored the extent to which a species' functional traits, abundance and/or the site at which it occurred predicted these three facets of its spatial pattern.

Results

Although at all sites most species were aggregated, site was consistently important in predicting a species' spatial pattern. Regenerative response to fire – whether a species is killed by fire and recruits solely via seeds, or survives and resprouts vegetatively after fire – was the functional trait most consistently useful in predicting a species' spatial pattern. Fire‐killed species tended to show more aggregated distributions than resprouters. Species present at multiple sites did not show consistency in their spatial patterns across those sites more than expected by chance alone.

Conclusions

Although functional traits relating to fire responses and water use predict species spatial distributions at the landscape level, at the fine scales we considered site effects were as important as functional traits in explaining spatial pattern. Within and between site heterogeneity, some of which can be generated by the stochastic properties of fire, may mask the deterministic effects of species functional traits.
Seedling emergence and growth of Quercus spp. following severe drought effects on a Pinus sylvestris canopy
Authors: Galiano Lucía , Martínez‐Vilalta Jordi , Eugenio Màrcia , Granzow‐de la Cerda Íñigo , Lloret Francisco
Published: September 2012

Questions

We addressed the following questions: (1) did defoliation and die‐off of the dominant Pinus sylvestris, induced by an extreme drought episode, favour emergence of other tree species; (2) did the defoliated canopies of P. sylvestris resulting from drought promote radial growth among other pre‐existing tree species seedlings under them?

Location

P. sylvestris forest in Central Pyrenees (NE Spain) affected by a severe drought in 2004–2005.

Methods

Despite increased focus on climate‐related forest die‐off, studies of the effects on regeneration processes following extreme drought remain scarce. We analysed whether an episode of drought‐induced mortality on the dominant P. sylvestris L. may act as a driver of vegetation shift. Seedlings of Quercus humilis Mill. and Q. ilex L. from 27 plots were sampled under P. sylvestris canopies with <50% and ≥50% defoliation (standing dead trees included) to determine age distribution and radial growth using a retrospective, dendrochronological approach.

Results

Drought‐induced canopy losses appear not to be compensated by regeneration of P. sylvestris. Recruitment of below‐canopy tree species (specifically Q. humilis and Q. ilex) that could potentially become dominant was high in the entire studied area. However, the spatial patterns of Quercus spp. regeneration following the 2004–2005 drought were complex. While the emergence of new Quercus spp. seedlings was reduced under open, drought‐induced canopies, growth of seedlings already established was favoured in open‐canopy conditions.

Conclusions

Although the effects of extreme drought events may disfavour the establishment of new recruits, enhanced growth responses of a pre‐established seedling bank could still contribute to accelerate forest dynamics under drier conditions. Because of the predicted increases in intensity and frequency of extreme droughts, monitoring studies are key to elucidate whether the initial patterns observed will be maintained in the long term, eventually leading to a vegetation shift.
Platelet Activation, Function, and Reactivity in Atherosclerotic Carotid Artery Stenosis: A Systematic Review of the Literature
Authors: Kinsella J. A. , Tobin W. O. , Hamilton G. , McCabe D. J. H.
Published: September 2012

An important proportion of transient ischemic attack or ischemic stroke is attributable to moderate or severe (50–99%) atherosclerotic carotid stenosis or occlusion. Platelet biomarkers have the potential to improve our understanding of the pathogenesis of vascular events in this patient population. A detailed systematic review was performed to collate all available data on ex vivo platelet activation and platelet function/reactivity in patients with carotid stenosis. Two hundred thirteen potentially relevant articles were initially identified; 26 manuscripts met criteria for inclusion in this systematic review. There was no consistent evidence of clinically informative data from urinary or soluble blood markers of platelet activation in patients with symptomatic moderate or severe carotid stenosis who might be considered suitable for carotid intervention. Data from flow cytometry studies revealed evidence of excessive platelet activation in patients in the early, sub-acute, or late phases after transient ischemic attack or stroke in association with moderate or severe carotid stenosis and in asymptomatic moderate or severe carotid stenosis compared with controls. Furthermore, pilot data suggest that platelet activation may be increased in recently symptomatic than in asymptomatic severe carotid stenosis. Excessive platelet activation and platelet hyperreactivity may play a role in the pathogenesis of first or subsequent transient ischemic attack or stroke in patients with moderate or severe carotid stenosis. Larger longitudinal studies assessing platelet activation status with flow cytometry and platelet function/reactivity in symptomatic vs. asymptomatic carotid stenosis are warranted to improve our understanding of the mechanisms responsible for transient ischemic attack or stroke.
Stroke Radiology and Distinguishing Characteristics of Intracranial Atherosclerotic Disease in Native South Asian Pakistanis
Authors: Khan Maria , Rasheed Asif , Hashmi Saman , Zaidi Moazzam , Murtaza Muhammad , Akhtar Saba , Bansari Lajpat , Shah Nabi , Samuel Maria , Raza Sadaf , Khan Umer Rais , Ahmed Bilal , Ahmed Bilawal , Ahmed Naveeduddin , Ara Jamal , Ahsan Tasnim , Munir S. M. , Ali Shoukat , Mehmood Khalid , Makki Karim Ullah , Ahmed Muhammad Masroor , Sheikh Niaz , Memon Abdul Rauf , Frossard Philippe M. , Kamal Ayeesha Kamran
Published: September 2012

Background

There are no descriptions of stroke mechanisms from intracranial atherosclerotic disease in native South Asian Pakistanis.

Methods

Men and women aged ≥18 years with acute stroke presenting to four tertiary care hospitals in Karachi, Pakistan were screened using magnetic resonance angiography/transcranial Doppler scans. Trial of ORG 10172 in Acute Stroke Treatment criteria were applied to identify strokes from intracranial atherosclerotic disease.

Results

We studied 245 patients with acute stroke due to intracranial atherosclerotic disease. Two hundred thirty scans were reviewed. Also, 206/230 (89·0%) showed acute ischaemia. The most frequent presentation was with cortically based strokes in 42·2% (87/206) followed by border-zone infarcts (52/206, 25·2%). Increasing degrees of stenosis correlated with the development of both cortical and border-zone strokes ( P = 0·002). Important associated findings were frequent atrophy (166/230, 72·2%), silent brain infarcts (66/230, 28%) and a marked lack of severe leukoaraiosis identified in only 68/230 (29·6%). A total of 1870 arteries were studied individually. Middle cerebral artery was the symptomatic stroke vessel in half, presenting with complete occlusion in 66%. Evidence of biological disease, symptomatic or asymptomatic was identified in 753 (40·2%) vessels of which 543 (72%) were significantly (>50%) stenosed at presentation.

Conclusion

Intracranial atherosclerotic disease is a diffuse process in Pakistani south Asians, with involvement of multiple vessels in addition to the symptomatic vessel. The middle cerebral artery is the most frequent symptomatic vessel presenting with cortical embolic infarcts. There is a relative lack of leukoaraiosis. Concomitant atrophy, silent brain infarcts and recent ischaemia in the symptomatic territory are all frequently associated findings.