bluuebunny/crossref_metadata_2025 huggingface dataset:
Super-resolution microscopy heads towards 3D dynamics
Authors: Weisshart Klaus , Dertinger Thomas , Kalkbrenner Thomas , Kleppe Ingo , Kempe Michael
Published: May 2013

Resolving fine details of subcellular structures is key to understanding the organization and function of cellular networks. Recent advances in far-field fluorescence microscopy provide the necessary tools to analyze these structures with resolutions well below the classical diffraction limit in all three dimensions. Technical improvements go hand-in-hand with new versions of switchable fluorophores that allow nonlinear optical effects to be more efficiently used to push the resolution limit down further. High contrast combined with the wide spectrum of available colors currently endow these fluorescence-based super-resolution techniques with the power to study the complexity of subcellular organelles and the relation of their constituting components down to the molecular level and under physiological conditions. In this way, they give us a far better understanding of the assembly of macromolecular complexes and their functions within a cell than has been possible before employing conventional imaging methods. In this review, we give an overview of the technical state-of-the art of these technologies, their fundamental and technical trade-offs, and provide typical application examples in this exciting field.
Behavioral Biases and Long-Term Care Insurance: A Political Economy Approach
Authors: De Donder Philippe , Leroux Marie-Louise
Published: May 2013

We develop a model where individuals all have the same probability of becoming dependent and vote over the social long-term care insurance contribution rate before buying additional private insurance and saving. We study three types of behavioral biases, all having in common that agents under-weight their dependency probability when taking private decisions. Sophisticated procrastinators anticipate their mistake when voting, while optimistic and myopic agents have preferences that are consistent across choices. Optimists under-estimate their own probability of becoming dependent but know the average probability, while myopics underestimate both. Sophisticated procrastinators attain the first-best allocation, while myopics and optimists insure too little and save too much. Myopics and optimists more (resp., less) biased than the median are worse off (resp., better off), at the majority-voting equilibrium, when private insurance is available than when it is not.
Prenatal molecular diagnosis of inherited neuromuscular diseases: Duchenne/Becker muscular dystrophy, myotonic dystrophy type 1 and spinal muscular atrophy
Authors: Esposito Gabriella , Ruggiero Raffaella , Savarese Maria , Savarese Giovanni , Tremolaterra Maria Roberta , Salvatore Francesco , Carsana Antonella
Published: May 2013

Background: Neuromuscular disease is a broad term that encompasses many diseases that either directly, via an intrinsic muscle disorder, or indirectly, via a nerve disorder, impairs muscle function. Here we report the experience of our group in the counselling and molecular prenatal diagnosis of three inherited neuromuscular diseases, i.e., Duchenne/Becker muscular dystrophy (DMD/BMD), myotonic dystrophy type 1 (DM1), spinal muscular atrophy (SMA).

Methods: We performed a total of 83 DMD/BMD, 15 DM1 and 54 SMA prenatal diagnoses using a combination of technologies for either direct or linkage diagnosis.

Results: We identified 16, 5 and 10 affected foetuses, respectively. The improvement of analytical procedures in recent years has increased the mutation detection rate and reduced the analytical time.

Conclusions: Due to the complexity of the experimental procedures and the high, specific professional expertise required for both laboratory activities and the related counselling, these types of analyses should be preferentially performed in reference molecular diagnostic centres.
Investigation of apparent non-albuminuric proteinuria in a primary care population
Authors: McTaggart Malcolm P. , Stevens Paul E. , Price Christopher P. , Newall Ronald G. , Pinnock Roger G. , Lamb Edmund J.
Published: May 2013

Background: There is debate as to whether using the urinary albumin- or protein-to-creatinine ratio (ACR or PCR) should be the primary test for proteinuria. Whilst albuminuria (increased ACR) in the absence of proteinuria (increased PCR) may be expected in some patients, the converse (i.e., proteinuria in the absence of albuminuria) is more unusual and its cause and significance are unclear. We investigated the nature of such apparent non-albuminuric proteinuria in a primary care population of patients.

Methods: ACR and PCR were measured in 569 urine samples from patients who either had chronic kidney disease or were at increased risk of the condition. Samples with apparent proteinuria (PCR ≥23 mg/mmol/≥200 mg/g) but no albuminuria (ACR <3.4 mg/mmol/<30 mg/g) were classified as ‘discrepant’ (37% of proteinuric samples, 6% of all samples); 27 of these samples were available for further analyses. The further analyses included electrophoresis, repeat measurement, immunoassays for markers of tubular proteinuria and use of alternative albumin and total protein methods.

Results: Electrophoresis did not identify significant proteinuria in the discrepant samples. The only evidence of tubular proteinuria following measurement of three urinary markers of the condition was a mildly increased α1-microglobulin-to-creatinine ratio in 10 of the 27 discrepant samples analysed, four of which also had a raised β-trace protein-to-creatinine ratio. Use of an alternative urinary total protein method resulted in significantly lower PCRs and 17 of the 27 samples were no longer classified as proteinuric.

Conclusions: We were unable to confirm the cause of a raised PCR without albuminuria in these patients and suspect that in most cases it is artefactual.
Bogomolov–Sommese vanishing on log canonical pairs
Authors: Graf Patrick
Published: May 2013

Let (X,D) be a projective log canonical pair. We show that for any natural number p, the sheaf

(

Ω
X
p

(
log

⌊
D
⌋

)

)

*
*

${(\Omega _X^p(\log \lfloor {D}\rfloor ))^{**}}$

of reflexive logarithmic p-forms does not contain a Weil divisorial subsheaf whose Kodaira–Iitaka dimension exceeds p. This generalizes a classical theorem of Bogomolov and Sommese.

In fact, we prove a more general version of this result which also deals with the orbifoldes géométriques introduced by Campana. The main ingredients to the proof are the Extension Theorem of Greb–Kebekus–Kovács–Peternell, a new version of the Negativity Lemma, the minimal model program, and a residue map for symmetric differentials on dlt pairs.

We also give an example showing that the statement cannot be generalized to spaces with Du Bois singularities.
As an application, we give a Kodaira–Akizuki–Nakano-type vanishing result for log canonical pairs which holds for reflexive as well as for Kähler differentials.
Congenital cytomegalovirus infection after maternal persistent immunoglobulin-M antibodies against cytomegalovirus prior to conception
Authors: Nakajima Yoshiyuki , Masaoka Naoki , Yamamoto Tatsuo
Published: May 2013

We describe a case of congenital cytomegalovirus (CMV) infection transmitted by an immunocompetent woman infected before conception with continuous hyper CMV-immunoglobulin M (IgM). A 33-year-old woman whose CMV-IgM levels were stable more than 8 months before conception was referred at 35 gestational weeks due to fetal unilateral cerebral ventriculomegaly. The maternal serum CMV-IgG was 61.7 U/mL, and the CMV-IgM was 3.89 U/mL. An infant girl weighing 2297 g was delivered transvaginally. The neonate was found to have congenital CMV infection. After delivery, the high maternal CMV-IgM level has continued for more than 2 years. In conclusion, although continuous hyper CMV-IgM is rare, the infants of infected women may develop congenital infection. It is our hope that the information provided in the present case will further aid clinicians in counseling patients who find themselves in this situation.
Ospemifene metabolism in humans in vitro and in vivo: metabolite identification, quantitation, and CYP assignment of major hydroxylations
Authors: Tolonen Ari , Koskimies Pasi , Turpeinen Miia , Uusitalo Jouko , Lammintausta Risto , Pelkonen Olavi
Published: May 2013

Background: The metabolism of ospemifene, a novel nonsteroidal selective estrogen receptor modulator, was investigated as part of its development.

Methods: Metabolite identification, tentative quantitation, and CYP assignment of ospemifene were performed in human liver microsomes or homogenate incubations and in plasma samples from volunteer humans. The potential contributions of CYP enzymes were determined by recombinant human CYPs. Metabolite identification and tentative quantification were performed by liquid chromatography-mass spectrometry.

Results: The relative abundances of metabolites produced were dependent on ospemifene concentration and liver preparation, but the largest quantities of 4- and 4′-hydroxy-ospemifene (and their glucuronides in smaller quantities) were produced in human liver microsomes at low ospemifene concentrations. Other metabolites were detected in in vitro incubation with human liver including a direct glucuronide of ospemifene and some metabolites with only minor abundance. In human plasma samples, 4-hydroxy-ospemifene was the most abundant metabolite, representing about 25% of the abundance of the parent compound. All the other metabolites detected in plasma, including 4′-hydroxy-ospemifene, represented <7% of the abundance of ospemifene. Several CYP enzymes participated in 4-hydroxylation, including CYP2C9, CYP2C19, CYP2B6, and CYP3A4, whereas CYP3A enzymes were the only ones to catalyze 4′-hydroxylation.

Conclusions: In vitro incubations with liver preparations provided a rather reliable starting point in the search for potential metabolites in clinical settings. The in vitro metabolite profile is informative for the in vivo metabolite profile, especially regarding the major hydroxylated metabolites. However, it is anticipated that extended in vivo exposures may result in an increased production of more distal metabolites from major metabolites.
One-pot synthesis and crystal structure of an unusual amidine derived from heterocyclic ketene aminal derivative
Authors: Yang Penghui , Wang Wenzhen , Duan Yanshan , Qu Chengtun , Zhang Qunzheng
Published: May 2013

One-pot reaction of Meldrum’s acid (1) and heterocyclic ketene aminal (HKA, 2) in acetone affords an unusual amidine HKA derivative 4. The reaction catalysts were optimized and it was found that l-proline is the best catalyst for the one-pot reaction. The mechanism is discussed. The structure of compound 4 was determined by single crystal X-ray analysis.
Synthesis of 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carboxylic acid derivatives and their antimicrobial activities
Authors: Şahan Emine , Yıldırım İsmail , Albayrak Sevil
Published: May 2013

The reaction of 1H-pyrazole-3-carboxylic acid chloride (1) with various hydrazine derivatives 2a–c yielded the corresponding N,N-disubstituted 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbohydrazides 3a–c. These products underwent Friedel-Crafts acylations with arenes to afford compounds 4a–c. Treatment of 1 with aromatic diamines produced 1H-pyrazole-3-carboxamides 5a–c, which were allowed to react with phenylhydrazine to give hydrazone derivatives 6a–c. The structures of all new compounds were established by IR, 1H and 13C NMR data and elemental analyses. The new compounds were evaluated for antimicrobial activities against Gram (-), Gram (+) bacteria and two yeasts using the disc diffusion method. N,N-Dimethylhydrazide derivative 3a is the most active compound of the series.
Sorption properties of hydrothermally modified wood and data evaluation based on the concept of Hansen solubility parameter (HSP)
Authors: Chirkova Jelena , Andersone Ingeborga , Grinins Juris , Andersons Bruno
Published: May 2013

The effect of the hydrothermal modification (HTM) of the deciduous woods birch and aspen on their sorption behavior has been investigated by the vapor sorption method. An analysis of the experimental results was carried out based on the concept of Hansen solubility parameters (HSP), which takes into account the contribution of different forces – dispersion forces, dipole action, and hydrogen bonding – to the total cohesion energy. Sorption isotherms were measured concerning the vapors of water, methanol, and ethanol with unmodified and HTM woods at 160°C and 170°C during 3 and 1 h, respectively. The choice of sorbates was based on the parts of the hydrogen bonding and dispersion force to cohesion energy, in decreasing order of the former and increasing order of the latter. As a criterion of sorption, the value of the monolayer capacity was used, which was derived from the Brunauer-Emmett-Teller equation. Vapor sorption with unmodified and modified wood increased with increasing dispersion force component of the HSP of the sorbate. However, more substantial increase occurred for HTM wood, that is, wood surface became more hydrophobic. The reason for this observation is the change in the decreasing ratio holocellulose/lignin upon HTM. However, the chemical structure of lignin is also changed by HTM.
ACE inhibition enhances bradykinin relaxations through nitric oxide and B1 receptor activation in bovine coronary arteries
Authors: Gauthier Kathryn M. , Cepura Cody J. , Campbell William B.
Published: May 2013

Bradykinin causes vascular relaxations through release of endothelial relaxing factors including prostacyclin, nitric oxide (NO) and epoxyeicosatrienoic acids (EETs). Bradykinin is metabolized by angiotensin converting enzyme (ACE) and ACE inhibition enhances bradykinin relaxations. Our goal was to characterize the role of bradykinin receptors and endothelial factors in ACE inhibitor-enhanced relaxations in bovine coronary arteries. In U46619 preconstricted arteries, bradykinin (10-11-10-8
m) caused concentration-dependent relaxations (maximal relaxation ≥100%, log EC50=-9.8±0.1). In the presence of the NO synthase inhibitor, N-nitro-L-arginine (L-NA, 30 μm) and the cyclooxygenase inhibitor, indomethacin (10 μm), relaxations were reduced by an inhibitor of EET synthesis, miconazole (10 μm) (maximal relaxation=55±10%). Bradykinin relaxations were inhibited by the bradykinin 2 (B2) receptor antagonist, D-Arg0-Hyp3-Thi5,8-D-Phe7-bradykinin (1 μm) (log EC50=-8.5±0.1) but not altered by the B1 receptor antagonist, des-Arg9[Leu8]bradykinin (1 μm). Mass spectrometric analysis of bovine coronary artery bradykinin metabolites revealed a time-dependent increase in bradykinin (1–5) and (1–7) suggesting metabolism by ACE. ACE inhibition with captopril (50 μm) enhanced bradykinin relaxations (log EC50=-10.3±0.1). The enhanced relaxations were eliminated by L-NA or the B1 receptor antagonist but not the B2 receptor antagonist. Our results demonstrate that ACE inhibitor-enhanced bradykinin relaxations of bovine coronary arteries occur through endothelial cell B1 receptor activation and NO.
In vitro maturation of Drosophila melanogaster Spätzle protein with refolded Easter reveals a novel cleavage site within the prodomain
Authors: Ursel Christian , Fandrich Uwe , Hoffmann Anita , Sieg Torsten , Ihling Christian , Stubbs Milton T.
Published: May 2013

Dorsoventral patterning during Drosophila melanogaster embryogenesis is mediated by a well-defined gradient of the mature NGF-like ligand Spätzle. Easter, the ultimate protease of a ventrally-restricted serine protease cascade, plays a key role in the regulation of the morphogenic gradient, catalyzing the activation cleavage of proSpätzle. As a result of alternative splicing, proSpätzle exists in multiple isoforms, almost all of which differ only in their prodomain. Although this domain is unstructured in isolation, it has a stabilizing influence on the mature cystine knot domain and is involved in the binding to the Toll receptor. Here, we report the expression and refolding of Easter, and show that the renatured enzyme performs the activation cleavage of two Spätzle isoforms. We determine the affinity of the prodomain for the cystine knot domain, and show that Easter performs a previously unknown secondary cleavage in each prodomain.
Sox appeal – Sox10 attracts epigenetic and transcriptional regulators in myelinating glia
Authors: Weider Matthias , Reiprich Simone , Wegner Michael
Published: May 2013

Sox10 belongs to the Sox family of high-mobility group-box transcription factors. It fulfils widespread and essential functions in myelinating glia at multiple stages of development such as glial specification, survival and terminal differentiation. To a large extent, these diverse activities can be attributed to its capacity to interact with different transcription factors in distinct regulatory networks. Beyond transcription factors, an increasing number of interaction partners are emerging with alternative impact on gene expression. These include components of the mediator complex, the Brahma-associated factor complex and histone deacetylases. Here, we discuss interactions with functional relevance in myelinating glia and link Sox10 function in these cells not only to gene transcription, but also to epigenetics and chromatin remodeling.
Low-Temperature Sintering of Nanosilver Paste on a Gold Film Surface
Authors: Luo Shiyong , Zhang Xinlin , Huang Xiaojun , Xu Wencai
Published: May 2013

Nanosilver paste with a low sintering temperature is a high-demand interconnection material for electronic devices and components due to its superior electrical, thermal, and thermomechanical properties, as well as the fact that it is lead free. This study presents a nanoscale silver paste that can be sintered at 300 °C using 60-nm silver particles and an ethyl cellulose solution. The rheological and thixotropic behaviors of the typical paste were characterized, and the paste's screen printing ability was analyzed in detail. The paste demonstrates typical shear thinning rheological behavior and thixotropy of pseudoplastic fluids. Thermal characteristics of the 60 nm silver particles were measured by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) to obtain a proper sintering temperature schedule. In this report, we also discussed the solid content, thermodynamic driving force for densification, and sintering process of the nanosilver particles. A 83 wt% of silver solid content at a heating rate of 20 °C/min was favorable for achieving a proper sintering densification.
Microalgae Technology: A Patent Survey
Authors: Tabernero Antonio , Martín del Valle Eva M. , Galan Miguel A.
Published: May 2013

For a long time now, it is known that an infinite number of compounds can be obtained from microalgae due to their promising composition. This fact is used by several companies to produce at medium-scale different high value products such as carotenoids. Furthermore, this last decade research in this topic has significantly increased given the potential solution these microorganisms present to meet World environmental agreements regarding CO2 emissions. However, the culture of large-scale microalgae in order to obtain products which are required in huge quantities (e.g., oil for manufacturing biodiesel) and at the same time removing pollutants appeared as a difficult task due to the great number of variables that must be taken into account. The photobioreactor design for cultivating the microalgae is perhaps the most important task, but there are other bottle-necks, such as the harvesting system, cleaning system, control system, the chosen microalgae, and the extraction of products from the microalgae. This review focuses on around 200 patents covering microalgae technology, from different photobioreactors designs to microalgae applications, in order to construct a perfect large-scale facility removing CO2 in the process.
On the Standardization of the Photocatalytic Gas/Solid Tests
Authors: Minero Claudio , Bedini Andrea , Minella Marco
Published: May 2013

The central problem for standardization of photocatalytic efficiency of whatever substrate on an illuminated catalyst is the rate evaluation. For gas/solid experiments different reactors, like batch or flow-through either continuous stirred-tank reactor (CSTR) or plug flow reactor (PFR), could be envisaged. The basic equations governing these reactors and the rate expression for them are presented here. Experiments show that a CSTR configuration presents a lot of advantages for practical use, as any volume, any shape of catalyst and any flow of gas into the reactor can possibly be used. A CSTR configuration is superior to the standardized PFR as the resistance to mass transfer can be reduced by inside forced ventilation. Consequently, it gives an evaluation of the photocatalytic rate more close to the actual surface one. The rate for CSTR at steady state must be calculated as r(Co) = Co F η/S(1−η), where η is the conversion.
Parallel-Connected Photovoltaic Inverters: Zero Frequency Sequence Harmonic Analysis and Solution
Authors: Carmeli Maria Stefania , Mauri Marco , Frosio Luisa , Bezzolato Alberto , Marchegiani Gabriele
Published: May 2013

High-power photovoltaic (PV) plants are usually constituted of the connection of different PV subfields, each of them with its interface transformer. Different solutions have been studied to improve the efficiency of the whole generation system. In particular, transformerless configurations are the more attractive one from efficiency and costs point of view. This paper focuses on transformerless PV configurations characterised by the parallel connection of interface inverters. The problem of zero sequence current due to both the parallel connection and the presence of undesirable parasitic earth capacitances is considered and a solution, which consists of the synchronisation of pulse-width modulation triangular carrier, is proposed and theoretically analysed. The theoretical analysis has been validated through simulation and experimental results.
Microencapsulation of Banana Juice from Three Different Cultivars
Authors: Chávez-Rodríguez Arturo M. , Pérez-Martínez Jaime David , Ibarra-Junquera Vrani , Escalante-Minakata Pilar , VillaVelazquez-Mendoza Carlos Ignacio , Dibildox-Alvarado Elena , de Jesús Ornelas-Paz José
Published: May 2013

In order to effectively process and utilize surplus bananas and those without the quality for export, in this research it is proposed to microencapsulate the banana juice by means of spray drying and using maltodextrin as the covering material. Three cultivars Enano gigante (Musa AAA, subgroup Cavendish), and the tetraploids hybrids (AAAA), FHIA-17 and FHIA-23 were selected for this research. Being Enano gigante, the cultivar shows the highest glass transition temperature. The drying parameters were established, depending upon the ratio of juice/maltodextrin and the drying air temperature. The optimal drying air temperature was 220°C for the three cultivars with a 20% juice/maltodextrin ratio for both the Enano Gigante and the FHIA-23, while in the FHIA-17 there were no significant differences between the juice/maltodextrin ratios. The morphology and size distribution of the microcapsules were observed by a scanning electron microscopy. The number of particles is directly proportional to the temperature and inversely proportional to the juice/maltodextrin ratio. A Weibull particle size distribution was common to all treatments. There is a correlation between the principal components and clustering analyses with the optimization of the system. The principal components analysis considers three Weibull parameters (obtained from the particle size distribution) and the powders moisture percentage.
Agent-based models of language competition
Authors: Castelló Xavier , Loureiro-Porto Lucía , San Miguel Maxi
Published: May 2013

This article uses computer simulations as a means of assessing two different models for the competition between two languages from the interdisciplinary perspective of complex systems. These models allow for the analysis of the role of bilingual speakers and they consider two of the basic factors determining the use of each language: their relative prestige and the language loyalty of their speakers. Here we assess the effect of these parameters in different social networks, with the aim of contributing to the understanding of the role of bilingualism and social networks in processes of language contact. We first present a qualitative analysis based on a simulation tool that we have designed, in order to visualize the dynamics of the models. Secondly, we consider a qualitative analysis of the role of complex networks, identifying mechanisms for the rapid extinction of a language and for situations of language segregation. Finally, we present a quantitative analysis which shows, counter-intuitively, a transition from a final scenario of language maintenance to one of language shift as language loyalty increases. Other findings are: (i) that the scenario of language coexistence is reduced in the presence of bilingual agents; and (ii) that networks which allow for local effects reduce further the situations for which language maintenance is possible.
Correlation between social and linguistic parameters in modeling language contact: evidence from endangered Finnic varieties
Authors: Markus Elena , Rozhanskiy Fedor
Published: May 2013

This article discusses a case of language competition between two minority languages, Votic and Ingrian. We analyze the sociolinguistic situation in the contact area, and the contact-induced linguistic changes in both languages. Although the two languages had a very similar fate, and the same premises for language competition, Ingrian appears to have been more socially prestigious and was for a long period of time gradually replacing Votic. It is shown that the two languages chose different strategies for interaction. The Ingrians preserved their strong identity but transformed their language significantly, and thus achieved an easier understanding with their neighbors. On the other hand, the Votes were unwilling to adapt their language to contact influence, but shifted easily to their neighbors' identity. We suggest distinguishing between two types of volatility: social volatility, which describes the willingness of a nation to shift to a new language and identity; and linguistic volatility, which denotes the readiness of speakers to adopt innovations from a neighboring language. In minority vs. minority competition, the two types of volatility often demonstrate inverse tendencies: high volatility on the linguistic level corresponds to low volatility on the social level, and vice versa.
Testosterone promotes glucose intolerance, lipid disorder and oxidative stress in type 1 diabetic rats
Authors: Morakinyo Ayodele Olufemi , Adekunbi Daniel Abiodun , Dada Kayode Akanni , Adegoke Olufeyi Adefunke
Published: May 2013

Background: A bidirectional relationship has been established between testosterone deficiency (TD) and type 2 diabetes mellitus (T2DM). Low testosterone level has been reported to be a predisposing factor to T2DM, whereas recent clinical studies have shown a high prevalence of low testosterone in diabetic individuals. However, it is not known if any relationship exists between type 1 diabetes mellitus (T1DM) and testosterone level. This study was designed to investigate the effects of TD on T1DM. Twenty-four Sprague-Dawley rats were randomly divided into four groups designated as control, diabetic, orchiectomized and orchiectomized-diabetic.

Methods: Diabetes was induced with an intravenous injection of alloxan, and orchiectomy was done under sterile conditions. Fasting blood glucose (FBG), insulin level, lipid and oxidative parameters were determined in all experimental rats.

Results: The area under the curve during oral glucose tolerance test showed that the orchiectomized-diabetic group expressed an enhanced ability to metabolize glucose than the diabetic group. The malondialdehyde level in the diabetic group was significantly higher compared with that in the control and orchiectomized groups. Moreover, there was a significant decrease in glutathione (GSH) activity and an increase in superoxide dismutase activity in the diabetic group compared with control. Meanwhile, the activities of GSH and catalase were significantly reduced in the orchiectomized as well as the orchiectomized-diabetic group when compared with both control and diabetic groups.

Conclusions: These data indicate that TD attenuates glucose intolerance under diabetic conditions and is equally associated with a considerable reduction in oxidative stress, which implies that testosterone may be a pro-oxidant.
Multiscale unified prediction of size/scale and Hall-Petch effects in the mechanics of polycrystalline materials
Authors: Frantziskonis George N.
Published: May 2013

Materials show size effects in their strength, i.e., improved strength as size decreases. Size effects have been studied extensively at a wide range of scales, from atomistic to continuum. Size effects depend on the scale of reference, as the physics change with increasing or decreasing scale. The work reported herein concentrates at scales near the average grain size in polycrystalline solids, where they are examined in conjunction with Hall-Petch effects. It presents a process for isolating physical information on a problem at specific spatial or temporal scales and applies it to Hall-Petch and size effects in one spatial dimension, extendable to higher dimensions. Importantly, the scale-isolated information captures the interactions among scales. As material failure and Hall-Petch effects are highly stochastic, a probabilistic approach to the present work is more appropriate than a deterministic one.
The arginine stimulation test: timing of peak is not a helpful parameter in the diagnosis of growth hormone deficiency
Authors: Gillis David , Granat Nadav , Strich David
Published: May 2013

Background: A typical peak timing in the glucagon stimulation test has been reported as an indication of growth hormone (GH) deficiency. Other stimulation tests have not been evaluated.

Objective: To evaluate the clinical usefulness of peak timing in the arginine stimulation test (AST) for growth hormone deficiency.

Methods: Retrospective review of 199 ASTs from one center. Outcomes included correlation of peak times with (a) frequency of deficient peak; (b) growth velocity standard deviation scores (GVSDSs); (c) other evidence of pituitary pathology; (d) results of confirmatory clonidine test; and (e) response to GH treatment.

Results: The peak in 83/109 (76.14%) sufficient tests occurred at typical times vs. 45/72 (62.5%) deficient tests (p<0.05). GVSDS on GH treatment was greater among patients with typical timing in the AST compared with atypical timing (2.67±0.59 vs. 0.46±1.17, p=0.021). No other variable correlated significantly with AST timing.

Conclusions: Timing of peak in the AST is not a clinically useful parameter.
Effect of oxygen tension on bacteria-stimulated cytokine production by fetal membranes
Authors: Klimova Natalia G. , Hanna Nazeeh , Peltier Morgan R.
Published: May 2013

Aim: Tissue culture studies indicate that bacterial products stimulate the production of proinflammatory cytokines by reproductive tissues. However, most of these studies have been performed under room air conditions, supplemented with 5% CO2. In this study, we tested whether O2 tension affects bacteria-stimulated cytokine production by extra-placental fetal membranes.

Methods: Cultures of full-thickness membranes, isolated choriodecidua, and isolated amnion were exposed to bacteria and incubated under 21% (room air) or 5% O2 for 18 h. Cytokine concentrations in conditioned medium was quantified by immunoassay.

Results: Culture under 5% O2 increased production of interleukin (IL)-1β and tumor necrosis factor (TNF)-α, but reduced IL-10 and IL-6 production by full membranes. Isolated choriodecidua responded to 5% O2 with increased IL-1β production and reduced IL-6 production, but had no effect on TNF-α and IL-10 production was not detected. No effect of O2 tension on IL-1β or IL-6 production by isolated amnion was detected, however, Escherichia coli-stimulated IL-10, TNF-α and IL-8 production was enhanced by culture under 5% O2.

Conclusions: Increased oxygen tension reduces the pro-inflammatory responsiveness of cell cultures to E. coli and promotes an anti-inflammatory cytokine profile. Differential effects of O2 tension on choriodecidua and amnion suggests a network of paracrine factors that regulate cytokine levels in response to changes in O2 tension.
Tempo and the perception of sentence modality
Authors: Cangemi Francesco , D'Imperio Mariapaola
Published: May 2013

Phonological models of intonation use abstract categories, such as pitch accents, to build a bridge between continuous modulations in
The interaction between competition, learning, and habituation dynamics in speech perception
Authors: Lancia Leonardo , Winter Bodo
Published: May 2013

Even though the outcome of the perception of phonological patterns is categorical, this process might still arise from continuous dynamics. Here, we propose a unified dynamical account of three types of behavior that are usually studied in isolation: short-term perceptual competition, long-term perceptual habituation, and even longer-term perceptual learning. We develop a model and test its predictions in two speech identification tasks on an acoustic continuum between the French words [sɛp] and [stɛp]. When presenting stimuli sequentially from one end of the continuum to the other, we found that the presentation order systematically changed the position of the perceptual switch from one word to the other. We also found that response times were slower and more variable around this perceptual switch, regardless of its position on the acoustic continuum. And, throughout the experiment, participants became more sensitive to small acoustic differences between stimuli. Our model can account for these results and for a surprising finding, namely that the initial presentation order affected responses even late in the experiment. Overall, our results point to the importance of the relation between fast processes responsible for competition, and slow processes responsible for habituation and learning in explaining how listeners can perceive speech categorically in a way that is both flexible and robust.
Preparing Teachers for Urban Students Who Have Been Labeled as Having Special Needs
Authors: Banks Tachelle , Obiakor Festus , Algozzine Bob
Published: May 2013

Preparing teachers to work in urban public schools – and to remain there – is a daunting challenge. In an age plagued with the overrepresentation of culturally and linguistically diverse (CLD) students placed in special education programs, it is important that teacher preparation programs within the field of special education devote attention to the devastating effects of deficit thinking. The current focus on the achievement gap and poor graduation rates has highlighted the challenges facing urban schools and their teachers in our nation. Many colleges and universities have ill-prepared or unprepared to work with CLD students in general and special education. This article discusses how teachers and service providers can be prepared to work with urban children and youth with and without special needs.
Expression of full-length human alkylglycerol monooxygenase and fragments in Escherichia coli
Authors: Mayer Matthias , Keller Markus A. , Watschinger Katrin , Werner-Felmayer Gabriele , Werner Ernst R. , Golderer Georg
Published: May 2013

Alkylglycerol monooxygenase (AGMO; EC 1.14.16.5) is the only enzyme known to cleave the O-alkyl ether bond of alkylglycerols in humans. It is an integral membrane protein with nine predicted transmembrane domains. We attempted to express and purify full-length and truncated forms of AGMO in Escherichia coli. Full-length AGMO could not be expressed in three different E. coli expression strains, three different expression vectors and several induction systems. We succeeded, however, in expression of three N-terminally strep-tagged truncated forms, named active sites 1, 2 and 3, with 205, 134 and 61 amino acids, respectively. Active site 1 fragment, containing two predicted transmembrane regions, a membrane associated region and all known amino acid residues important for catalytic activity, was not fully soluble even in 8 M urea. Active site 2 containing only one predicted membrane associated domain required 8 M urea for solubilisation and eluted in gel filtration in 1 M urea as a trimer. Active site 3 with no hydrophobic domain eluted in gel filtration in 1 M urea as monomer and dimer. These results show that even truncated forms of AGMO are barely soluble when expressed in E. coli and show a high tendency for aggregation.
Folate homeostasis of cancer cells affects sensitivity to not only antifolates but also other non-folate drugs: effect of MRP expression
Authors: Peters Godefridus J. , Kathmann Ietje , Lemos Clara , Hooijberg Jan Hendrik , Losekoot Nienke , Jansen Gerrit
Published: May 2013

Sensitivity to antifolates can be decreased by endogenous or exogenous folates. Leucovorin protects cancer patients against toxicity of the dihydrofolate reductase inhibitor methotrexate (MTX), while folic acid is used to protect rheumatoid arthritis patients against MTX. Folates and antifolates can be effluxed from the cell by ABC transporters multidrug resistance protein 1 (MRP1), 2 and 3. We previously demonstrated in 2008 ovarian cancer cells that MRP overexpression reduced cellular folate content by 40%, while folate depletion increased expression of MRP1. As MRPs mediate resistance to several unrelated drugs, we investigated whether folate status would affect sensitivity to doxorubicin, daunorubicin, etoposide and vincristine. Ovarian cancer 2008 cells and its MRP1 transfected variant (2008/MRP1) were adapted from normal folate medium [2.3 μM; high folate (HF) cells] to short-term folate depletion (up to 7 days) (low folate cells); drugs were added after 2 days and sensitivity was tested by the MTT test after 3 additional days. The effect on folate homeostasis was evaluated by measurement of intracellular homocysteine using high-performance liquid chromatography and glutathione using a kit. MRP expression of wild-type (WT) 2008 cells did not increase homocysteine pools in 2008/MRP1 cells. Three day folate depletion increased homocysteine pools 23-fold in 2008 cells and 8.6-fold in the MRP variant. Folate depletion increased glutathione 20%–40% in 2008/WT and 2008/MRP1. In 2008 HF cells MRP1 expression did not affect sensitivity to MTX, but induced 4- to 10-fold resistance to doxorubicin, daunorubicin, etoposide and vincristine. Folate depletion decreased 50% growth inhibition (IC50) for MTX in both 2008 variants 25- to 4-fold, but that to doxorubicin and daunorubicin approximately 2-fold. Sensitivity to etoposide and vincristine was not affected. In conclusion, folate depletion markedly increased homocysteine, but moderately increased glutathione. Folate depletion increased MTX sensitivity, but effects on other drugs were most pronounced in WT cells, probably because MRP expression is already high in transfected variants.
The effects of marble dust and fly ash on clay soil
Authors: Zorluer Ismail , Gucek Suleyman
Published: May 2013

The use of waste materials as an additive in soil stabilization has been widespread. This is important in terms of recycling of waste materials and reducing environmental pollution. The objective of this study is to investigate the beneficial reuse of marble dust and fly ash in soil stabilization. Tests were performed on clay soil mixtures amended with marble dust and fly ash. Marble dust was used as an activator due to fly ash being inadequate for self-cementing. Unconfined compressive strength (q
u), freeze-thaw, swelling, and California bearing ratio (CBR) tests were conducted to investigate the effect of marble dust and fly ash, curing time, and molding water content on geotechnical parameters. Addition of marble dust and fly ash increased unconfined compressive strength, CBR, and freeze-thaw strength, but these additives decreased swelling potential and grain loss after freeze-thaw. Increasing the curing time results in increased strength of mixtures and decreased grain loss. As a result, this study shows that the geotechnical properties of clay soil are improved with the addition of marble dust and fly ash. This is an economical and environmentally friendly solution.
An experimental study on the performance of self-compacting lightweight concrete exposed to elevated temperature
Authors: Wu Xi , Wu Zhi-min , Zheng Jian-jun , Ueda Tamon , Yi Sheng-hui
Published: May 2013

This paper presents an experimental study on the spalling characteristics, mass loss ratio, ultrasonic pulse velocity, compressive strength and flexural strength of self-compacting lightweight concrete (SCLC) at elevated temperature. Four types of SCLC specimens with and without polypropylene fibres (PPFs) and one type of normal concrete (NC) specimens were cast and tested. Based on the experimental observations and results, it was found that, compared with NC, SCLC spalls at a lower temperature but maintains a higher residual strength. For all the concretes the peak mass loss ratio increased but the relative ultrasonic pulse velocity decreased with the rise of temperature. At a given elevated temperature, the relative compressive strength and flexural strength of SCLC was larger than those of NC. The addition of PPFs greatly reduced the risk of spalling of SCLC. The thermal damage and the loss in residual mechanical properties of SCLC with PPFs were smaller compared with that without PPFs.
Rehabilitation of Kolkata's first Victorian-age brick sewer
Authors: Basu Nilangshu Bhusan , Boral Somenath , Mandal Sushil Kumar , Dey Ayanangshu
Published: May 2013

As early as 1868, the first man-entry brick sewer of Kolkata (then Calcutta) along Lenin Sarani (then Dharamtolla Street) was commissioned as a part of an organised effort to provide a comprehensive combined sanitation facility. Subsequently, the city saw its golden age of construction of large-size brick sewers in its core area. Gradual and continuous deterioration over almost 140 years of its service life had caused occasional blockage, collapses, heavy siltation and water logging, mostly inflicted by lack of adequate and timely maintenance. In 2008, the Kolkata Municipal Corporation embarked on a major undertaking of refurbishing this most ancient and critically important brick sewer by trenchless technology. Its entire length of 2·8 km was rehabilitated using glass-reinforced plastic liners. The total cost of the project was more than £8.5 million (as in 2010) and it took about 2 years to refurbish and recommission (in 2010) this sewer to service.
What lessons can be learnt from studying a Roman hydraulic structure in a little village in Southern Italy?
Authors: De Feo G. , Ribera F. , Abbondandolo S. , De Gisi S.
Published: May 2013

The aim of this paper is to study a Roman hydraulic structure in a little village in Southern Italy in order to learn some lessons from the past and identify potential ideas for implementation. Despite increasing global urbanization a significant percentage of people inhabiting inland areas need critical infrastructure service including water supply systems. The fountain system under consideration in this paper is a good example of a sustainable use of the local territory, which is desirable for modern development of infrastructure. In terms of capital investment and management costs, it is better to try and solve supply issues locally in inland areas rather than to construct mega hydraulic works. During the late Roman Republic, some small inland villagers were obliged to think as well as to act locally. The Roman system investigated here highlights the use of local building elements (and traditional construction techniques) in a sort of ‘zero kilometre’ philosophy.
Household rainwater harvesting system – pilot scale gravity driven membrane-based filtration system
Authors: Kus B. , Kandasamy Jaya , Vigneswaran S. , Shon H. K. , Moody G.
Published: May 2013

This paper presents the results of a pilot scale study consisting of pre-treatment with a granular activated carbon (GAC) filter followed by membrane filtration. Detailed characterisation of rainwater tanks has highlighted that turbidity, dissolved organic carbon (DOC) and heavy metals, in particular lead, were not compliant with the 2004 Australian Drinking Water Guidelines (ADWG). Further, organic matter present in the water causes membrane fouling and leads to carcinogenic compounds upon chlorination. A GAC filter was used as a first step to remove dissolved organic matter (measured in terms of DOC) in particular and also to reduce the concentration, of turbidity and lead. Membrane filtration can remove any remaining solids reducing the concentrations of turbidity and microorganisms. In this study a pilot scale rainwater treatment system consisting of a gravity fed GAC filter and membrane filter (Ultra Flo) was operated for a period of 120 days. The performance of this system was assessed in terms of membrane flux and improvement in water quality measured against the 2004 Australian Drinking Water Guidelines. Determination of the flux especially in the later stages of membrane operation was important to be able to size the filters in a manner that meets the expected demand. The treatment system of GAC filter and membrane filter was effective in reducing the turbidity, DOC and heavy metals. The system reduced the turbidity to levels of 0.3–0.4 NTU, below the ADWG limit of 1 NTU. The concentration of DOC was reduced to below the 2004 Australian Drinking Water Guidelines limit of 0.2 mg/L. The concentration of lead was reduced to less than 0.005 mg/L, and below the ADWD limit of 0.01 mg/L. The concentrations of all other heavy metals were well within the ADWG limits. Further, the GAC filter removed a majority of the organic substances from raw rainwater collected from the roof. After the initial flux decline, the stable flux achieved was 0.47 L/m2/h consistently over the final 60 days of the experiment.
Assessment of Escherichia coli reactivation after photocatalytic water disinfection using flow cytometry: comparison with a culture-based method
Authors: Kaur Jasjeet , Karthikeyan R. , Smith R.
Published: May 2013

The photocatalytic process generates highly reactive oxidative species, such as hydroxyl radicals, which enable mineralization of cellular compounds. Microorganisms often tend to lose their culturability after disinfection, but could remain viable to proliferate under optimum conditions. Estimation of bacterial counts using culture-based methods pose limitations in differentiating viable, non-viable, and viable but non-culturable (VBNC) cells. Presence of viable and VBNC state cells in disinfected water could pose a potential health risk and accurate estimation of these cells through a molecular method is critical. Assessment of live/dead states of an indicator waterborne pathogen, Escherichia coli (ATCC®10798) after disinfection was conducted using flow cytometry. Photocatalysis was carried out under low pressure ultraviolet (LP UV) radiation alone and at four titanium dioxide (TiO2) concentrations (1, 0.75, 0.5 and 0.1 g/L). During the repair period, flow cytometry showed 4–5 log10 higher cell counts than the culture-based method. Photocatalysis using 0.1 g/L TiO2 resulted in 50% cells with intact cell membrane during the repair period and lowered the repair rate of the ATCC®10798, E. coli after disinfection.