bluuebunny/crossref_metadata_2025 huggingface dataset:
Dielectric Properties and Microwave Heating Characteristics of Sodium Chloride at 2.45 GHz
Authors: Liu Chenhui , Zhang Libo , Peng Jinhui , Qu Wenwen , Liu Bingguo , Xia Hongying , Zhou Junwen
Published: May 2013

The effects of moisture content and temperature on the dielectric property of sodium chloride were investigated by using open-ended senor dielectric measurement system at the frequency of 2.45 GHz. Moisture content is a major influencing factor in the variation of dielectric properties. Dielectric constant, loss factor and loss tangent all increase linearly with moisture content increasing. Three predictive models were developed to obtain dielectric constant, loss factor, loss tangent and of sodium chloride as linear functions of moisture content. Temperature between 20 °C and 100 °C has a positive effect on dielectric constant and loss factor. Penetration depth decreased nonlinearly with moisture and temperature increasing. A predictive model was developed to calculate penetration depth for sodium chloride as a fifth function of moisture content. In addition, the measurements indicate that the particles temperature increases linearly with microwaving heating time at different power levels. The knowledge gained from these results is useful in developing more effective applications of microwave drying and designing better sensors for measuring moisture content of sodium chloride.
Factors Capable of Modifying the Response of Pseudomonas aeruginosa to the Inactivation Induced by Heterogeneous Photocatalysis
Authors: Araujo Paula Z. , Oppezzo Oscar J. , Ibáñez Jorge A. , Blesa Miguel , Pizarro Ramón A.
Published: May 2013

The heterogeneous photocatalysis (HP) procedure has been demonstrated to be an interesting method for disinfecting water. It is effective for inactivating Pseudomonas aeruginosa, but its effectiveness may be reduced due to the action of several factors which are able to affect bacterial radio-sensitivity. The results reported here show the influence of nutritional stress and pre-exposure to sub-lethal UVA doses on the efficiency of the inactivation of P. aeruginosa by HP. Both previous exposures to low UVA fluencies and nutrient deprivation induce bacterial resistance to this process, in concordance with previous observations about the lethal effect of direct UVA irradiation. Starvation plus pre-irradiation did not have synergistic or antagonist effects. Kinetic parameters are presented for all three cases. These factors should be taken into account in the design of a water treatment process.
A Comparison of Monomeric Phenols Produced from Lignin by Fast Pyrolysis and Hydrothermal Conversions
Authors: Du Lin , Wang Ze , Li Songgeng , Song Wenli , Lin Weigang
Published: May 2013

Lignin, a by-product in biorefining industries such as lignocellulose-to-ethanol and paper-making processes, is a promising renewable source for value-added phenolic chemicals. Hydrothermal conversion and fast pyrolysis are two main thermo-chemical approaches for depolymerization of lignin. Hydrothermal conversion is a low temperature (250–500°C) and high pressure (5–30 MPa) process particularly suited for high moisture materials, whereas fast pyrolysis takes place at atmospheric pressure and moderate temperatures in the absence of oxygen and requires drying of the feedstock. In this paper, we present experimental results that provide a comparison of distributions of monomeric phenols produced by fast pyrolysis and hydrothermal conversion of lignin. Hydrothermal conversion experiments were performed in a 150 ml autoclave at 300°C for 30 minutes with different alkaline concentrations. Pyrolysis was carried out in a spouted bed reactor at 500°C. Hydrothermal conversion of lignin under 1 M alkaline solutions resulted in lower char yields (12.1%) compared to fast pyrolysis, which resulted in 54.5% solid yields. Monomer phenols obtained from hydrothermal conversion of lignin were found to have a narrower distribution dominated by catechol and its methyl derivative. In contrast, fast pyrolysis produced a wider distribution of monomeric phenols dominated by guaiacol and its derivatives with various chains substituted para to the hydroxyl group. Mechanisms of lignin fast pyrolysis and the methoxy group conversion under hydrothermal conditions were proposed respectively. In conclusion, hydrothermal technology is better suited for production of value added monomer phenols from lignin.
Microwave Drying Characteristics and Kinetics of Lotus (Nelumbo nucifera Gaertn.) Seeds
Authors: Tian Yuting , Liang Jing , Zeng Hongliang , Zheng Baodong
Published: May 2013

Lotus (Nelumbo nucifera Gaertn.) seeds were dried in a laboratory quality microwave oven to determine the effects of microwave output and mass load on drying time and drying rate. By increasing the microwave output power (231–539 W) and mass load (100–200 g), the drying time decreased from 36 to 13 min and increased from 18 to 30 min, respectively. The drying process can be divided into three stages: the heating period, constant rate period, and falling rate phase. A kinetics model which could describe the relationship of moisture ratio and drying time was established based on experimental data. The results show the drying procedure of lotus seeds could accurately be described by the Page model. The predicted values of the model were nearly consistent with the observed values. The moisture content and drying rate during the drying procedure matched the predicted results estimated by the Page model.
Image Analysis of Bread Crumb Structure in Relation to Mechanical Properties
Authors: Shibata Mario , Tsuta Mizuki , Sugiyama Junichi , Fujita Kaori , Kokawa Mito , Araki Tetsuya , Nabetani Hiroshi
Published: May 2013

To correlate the mechanical properties with the crumb structure of bread, a simple and objective method of measuring air bubbles of crumb samples was developed using an image scanner and digital image processing. Four images of the sample scanned in four orthogonal directions were aligned and combined to obtain an enhanced image in which air bubble regions were emphasized by min-operation, selecting the minimum gray level among the four images for each pixel. Next, Otsu’s method was applied to threshold each sub-image of the enhanced image in order to quantify the geometries of the air bubbles precisely, and then the black regions of the image were found to be air-bubbles. As a result, the four air-bubble parameters of the bread samples were determined to be mean bubble area, mean bubble perimeter, number of bubbles, and bubble area ratio. In addition, the viscoelastic properties of the samples were measured by the creep test and determined to significantly correlate with the bubble area ratio (r > 0.59, p < 0.05). This indicates that with increasing air-bubble area, crumb hardness increases. The proposed method is inexpensive and easy to operate, and thus is considered to be applicable to the quality assessment in food factories.
An Observer Based Methodology for Estimating Concentration-Dependent Diffusion Coefficients in Drying Considering Shrinkage
Authors: Martínez-Vera Carlos , Schaum Alexander , Calderón Jesús Alvarez , Vizcarra-Mendoza Mario G.
Published: May 2013

In this work, we present a method for estimating the diffusion coefficient in isothermal drying processes in those cases in which the associated shrinkage cannot be neglected. We assume that the drying process is described by the diffusion equation and depart of a numerical solution of reduced order to the corresponding problem. The method chosen for identifying the parameter in question is based in a high gain filter. As an example for showing the proposed method we take a solid presented by Aguerre et al. (Latin American Applied Research 2008;38:345–9). First, we solve the direct problem for generating an average moisture content profile and the corresponding radius profile. Taking the radius evolution as known data and the average moisture evolution as the innovation term in the filter, we solve the inverse problem and as a result a moisture-dependent diffusion coefficient is obtained, which is refined in a posterior and final optimization step.
Production and Characterization of Sugary Cassava Syrup
Authors: Souza Hugo A. L. , Souza Thaís C. L. , Lopes Alessandra S. , Pena Rosinelson S.
Published: May 2013

A group of cassava landraces that occur naturally in Amazonia (Manihot esculenta Crantz) are known as mandiocaba or sugary cassava because they have high free sugar content, making them a possible feedstock for the production of syrup. The objective of the study was to evaluate the technological viability of obtaining sugary cassava syrup and to characterize the physical and physicochemical properties of the product. The yield of the syrup (80 °Brix) obtained from the manipueira (liquid obtained by crushing and filtering the cassava) concentration was 262.72 g per plant. The reducing sugars represented 77.26% of total sugars, the density was 1.4210 g cm–3 at 20°C, and the volumetric expansion coefficient was 38.6 m K–1. The Newtonian behavior and activation energy (≥69.65 kJ gmol–1) were similar to that of honey found in the literature.
ACE-Inhibitory Peptide Isolated from Fermented Soybean Meal as Functional Food
Authors: Wang Haikuan , Zhang Shanting , Sun Yan , Dai Yujie
Published: May 2013

Biologically active peptides as components in functional foods exhibit diverse activities and exert health effects in humans, just as the angiotensin I-converting enzyme (ACE)-inhibitory peptide exerts an antihypertensive effect. The solid-state fermentation of soybean meal was conducted using Bacillus subtilis natto at an appropriate temperature to accelerate proteolytic hydrolysis, and the crude extract containing ACE-inhibitory peptides was sequentially purified by ultrafiltration, gel chromatography and reverse phase-HPLC. A novel ACE-inhibitory peptide was obtained and its ACE-inhibitory activity was 84.1% with an IC50 value of 0.022 mg/ml. The results suggest that these ACE-inhibitory peptides obtained from the solid-state fermentation of soybean meal using B. subtilis natto have good potential for application in the management of hypertension and the fermented soybean meal has good potential for application in the production of a novel physiologically functional food.
Prosodic accommodation in language contact: Spanish intonation in Majorca
Authors: Romera Magdalena , Elordieta Gorka
Published: May 2013

In this article we study a language contact situation in Majorca, Spain, in which adult monolingual speakers of Spanish who arrived recently in Majorca acquire aspects of Majorcan Catalan prosody. Although the possibility that the adoption of features can take place directly from Catalan is not rejected, we provide evidence that it can be an indirect process, through a process of accommodation (Trudgill 1986; Giles and Coupland 1991) to the L2 variety of Spanish spoken by L1 Majorcan Catalan speakers. An experiment was set up in which we recorded four native Spanish speakers who arrived recently in Majorca holding a semi-directed conversation in Spanish with a native speaker of Majorcan Catalan. The results showed consistent adoption of prosodic features of L2 Majorcan Spanish in interrogative sentences (not in declaratives). The results support the idea that the adoption of prosodic features of Majorcan Catalan by monolingual Spanish speakers can take place in early stages of contact. Our article also shows that subjective factors such as determination towards integration play a fundamental role in determining the degree of accommodation. Finally, salience of prosodic features is claimed to play a role in the selection of transferred features.
Positive impact of Tai Chi Chuan participation on biopsychosocial quality of life compared to exercise and sedentary controls: a cross-sectional survey
Authors: Baxter Alex , J. P. Francis Andrew
Published: May 2013

Tai Chi Chuan (TCC) is a traditional Chinese medicine practice and martial art with biopsychosocial aspects. This study aimed to examine the impact of participation in TCC on multiple domains of Quality of Life (QoL) and to assess the involvement of the psychological factors of self-efficacy, Locus of Control (LoC) and Hope in these effects. A total of 68 participants from the general community (13 males and 55 females) aged between 18 and 68 (M=43.55 years) and not currently suffering from a mental or physical illness took part in the study. It was found that TCC participants, as a group, scored significantly better than those in sedentary (book club) and active (gym exercise) control conditions on Psychological and Physical QoL, and that the Physical QoL benefits of TCC continue to accrue with years of practice. The three psychological factors were shown to variously mediate (self-efficacy) and moderate (internal LoC and Hope) this latter relationship. Whilst the results bear limitations (in particular small sample sizes), it is hoped that these findings will encourage further research into TCC, and consideration of TCC as part of the range of treatment options available in community-based mental and physical health management.
The z-classes of quaternionic hyperbolic isometries
Authors: Gongopadhyay Krishnendu
Published: May 2013

Let be the n-dimensional quaternionic hyperbolic space. The group acts as the isometry group of . We analyze when two isometries of commute. We apply this analysis to determine the conjugacy classes of centralizers or the z-classes in . Furthermore, we count the conjugacy classes of centralizers.

In Appendix A, we show that our methods can be used to obtain the centralizers up to conjugacy in real and complex hyperbolic geometries as well. This provides a unified approach to the determination of the conjugacy classes of centralizers in hyperbolic geometries.
Fully inert subgroups of divisible Abelian groups
Authors: Dikranjan Dikran , Giordano Bruno Anna , Salce Luigi , Virili Simone
Published: May 2013

A subgroup H of an Abelian group G is said to be fully inert if the quotient is finite for every endomorphism ϕ of G.
Clearly, this is a common generalization of the notions of fully invariant, finite and finite-index subgroups. We investigate the fully inert subgroups of divisible Abelian groups, and in particular, those Abelian groups that are fully inert in their divisible hull, called inert groups. We prove that the inert torsion-free groups coincide with the completely decomposable homogeneous groups of finite rank and we give a complete description of the inert groups in the general case. This yields a characterization of the fully inert subgroups of divisible Abelian groups.
On the rank of quotients of hyperbolic groups
Authors: Weidmann Richard
Published: May 2013

We show that the rank does not decrease if one passes from a torsion-free locally quasi-convex hyperbolic group to the quotient by the normal closure of certain high powered elements. An argument provided by Ilya Kapovich further shows that the quasiconvexity assumption cannot be dropped without adding other assumptions.
On zero divisors with small support in group rings of torsion-free groups
Authors: Schweitzer Pascal
Published: May 2013

Kaplansky's zero divisor conjecture envisions that for a torsion-free group
Quadratic unipotent blocks in general linear, unitary and
symplectic groups
Authors: Srinivasan Bhama
Published: May 2013

An irreducible ordinary character of a finite reductive group is called
quadratic unipotent if it corresponds under Jordan decomposition
to a semisimple element s in a dual group such that .
We prove that there is a bijection between, on the one hand, the
set of quadratic unipotent characters of or
for all and, on the other hand, the
set of quadratic unipotent characters of for all .
We then extend this correspondence to ℓ-blocks for certain ℓ
not dividing q.
An adjoint method for proving identifiability of coefficients in
parabolic equations
Authors: DuChateau Paul
Published: May 2013

This article presents a uniform approach for dealing with the question of
uniqueness in the identification of unknown coefficients in parabolic
partial differential equations in n dimensions. It is shown that the
unknown coefficients in a parabolic inverse problem are uniquely determined
by the given observation(s) if an associated adjoint problem is
approximately controllable. Additionally, the method provides an explicit
expression for the gradient of an associated output least squares error
functional and may provide a means for solving the inverse problem directly.
The flexibility of the method is illustrated in examples of identifications
involving one or more coefficients in appearing in a single equation or
system and based on various boundary and interior observations.
A rare association between Rathke’s cyst and hypophysitis in a patient with delayed sex development and growth failure
Authors: Takahashi Daisuke , Kobayashi Hiroyuki , Kubota Kanako , Suzuki Yasuto , Nakamura Akie , Ishizu Katsura , Nakanishi Masanori , Nagashima Tetsuro , Tajima Toshihiro
Published: May 2013

We report an 18-year-old Japanese male with a lack of secondary sex characterization and growth failure caused by a rare association between Rathke’s cyst and hypophysitis. He was referred to us because of delayed secondary sex characterization. Endocrinological examination showed panhypopituitarism, and the replacement of hydrocortisone, levothyroxine, and desmopressin acetate (DDAVP) was initiated. Brain magnetic resonance imaging (MRI) showed a suprasellar region and a swollen pituitary stalk. The mass was partially resected using the transsphenoidal approach. The pathological diagnosis was hypophysitis and Rathke’s cyst. Follow-up MRI performed 1 year after surgery showed that the size of sellar region had not changed. After surgery, in addition to pre-operative hormonal replacement, growth hormone and testosterone were initiated. Two years later, the size of sellar region remains unchanged.

In conclusion, while an association between Rathke’s cyst and hypophysitis is rare, we suggest that this condition should be included in differential diagnosis of the sellar region, even in adolescents.
Nanotechnologies in tissue engineering
Authors: Bigdeli Amir K. , Lyer Stefan , Detsch Rainer , Boccaccini Aldo R. , Beier Justus P. , Kneser Ulrich , Horch Raymund E. , Arkudas Andreas
Published: May 2013

As an interdisciplinary field, tissue engineering (TE) aims to regenerate tissues by combining the principles of cell biology, material science, and biomedical engineering. Nanotechnology creates new materials that might enable further tissue-engineering applications. In this context, the introduction of nanotechnology and nanomaterials promises a biomimetic approach by mimicking nature. This review summarizes the current scope of nanotechnology implementation possibilities in the field of tissue engineering of bone, muscle, and vascular grafts with forms on nanofibrous structures.
Correlation or Causation?
Authors: Crocker James
Published: May 2013

This paper argues that The Consolation of Philosophy by Anicius Manlius Severinus Boethius and Either/Or by Søren Kierkegaard bear certain striking similarities in their content, form, arguments, and in the way key ideas are expressed. It proposes that the explanation for this similarity could be causal dependency: The Consolation impacted Kierkegaard, consciously or unconsciously, in the development of Either/Or. Regardless of whether this is correct or not, it further proposes that the correlation between these two works is close enough that an intertextual reading is valuable for the comprehension of both The Consoluation and Either/Or. This paper seeks to prove this by executing such a reading.
Thermal degradation kinetics and mechanism of epoxidized natural rubber
Authors: He Canzhong , Wang Yueqiang , Luo Yongyue , Kong Lingxue , Peng Zheng
Published: May 2013

Thermal resistance is one of the most dominative properties for polymer materials. Thermal degradation mechanisms of epoxidized natural rubber (ENR) and NR are studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The results show that, the introduction of epoxy groups into the NR molecular main chain leads to a remarkable change in the degradation mechanism. The thermal stability of ENR is worse than that of NR. For the first thermooxidative degradation stage, the thermal decomposition mechanism of ENR is similar to that of NR, which corresponds to a mechanism involving one-dimensional diffusion. For the second stage, the thermal decomposition mechanism of ENR is a three-dimensional diffusion, which is more complex than that of NR. Kinetic analysis showed that activation energy (Eα), activation entropy (ΔH) and activation Gibbs energy (ΔG) values are all positive, indicating that the thermooxidative degradation process of ENR is non-spontaneous.
Thymidylate synthase inhibitors for thoracic tumors
Authors: Peters Godefridus J. , Galvani Elena , Jansen Gerrit , Assaraf Yehuda , Giovannetti Elisa
Published: May 2013

Thymidylate synthase (TS) is a valid target for treatment of non-small cell lung cancer (NSCLC) and mesothelioma (MPM). The TS inhibitor pemetrexed (PMX) is now commonly used in combination with cisplatin (CDDP) or carboplatin, in the first-line setting for both of these lethal diseases. A combination of another TS inhibitor, Tomudex with CDDP, demonstrated similar activity in MPM patients. However, the efficacy of TS inhibitors is limited by uptake, metabolism and target affinity. While uptake of most antifolates is mediated by the reduced folate carrier, PMX is also a good substrate for the proton-coupled folate transporter (PCFT), which displays optimal activity at the acidic pH of the tumor microenvironment. NSCLC and MPM have a variable expression of PCFT, which might be caused by the differential methylation status of the PCFT promoter, resulting in decreased anticancer activity. PMX and TDX activity also depends on polyglutamylation, catalyzed by folylpolyglutamate synthetase (FPGS), which results in intracellular retention and thus enhanced cytotoxicity. We demonstrated that resistance to the classical antifolate methotrexate in human leukemia cells with a marked loss of FPGS activity was associated with impaired splicing of FPGS pre-mRNA. Moreover, we recently showed that the sensitivity of MPM patients to PMX-carboplatin is related to tumor TS expression. Patients with low TS mRNA levels had a significantly longer overall survival (20 vs. 7 months) compared with patients with high expression. Intriguingly, recent trials demonstrated that histology plays an important role in the sensitivity of NSCLC patients, and PMX-CDDP is now approved only for adenocarcinoma patients. These results might be partly explained by the higher TS expression detected in lung tumors of squamous histology. In summary, the clinical success of TS inhibitors may depend on biomarker-driven patient selection, and further studies should evaluate the genetic/epigenetic factors involved in the modulation of these biomarkers in the preclinical and clinical setting.
Prediction and optimization of stability parameters for titanium dioxide nanofluid using response surface methodology and artificial neural networks
Authors: Sadollah Ali , Ghadimi Azadeh , Metselaar Ibrahim H. , Bahreininejad Ardeshir
Published: May 2013

The effect of various process parameters on the stability of TiO2 nanofluid, which can mostly be defined as zeta potential and particle size, was studied using response surface methodology (RSM) by the design of experiments and was predicted through a trained artificial neural network (ANN). The process parameters studied were weight percentage of surfactant (sodium lauryl sulfate) (0.01–0.2 wt%) and the value of pH (10–12). Central composite design and the RSM were employed to develop a mathematical model as well as to define the optimum condition. A three-layered feed-forward ANN model was designed and used for the prediction of the stability parameters. From the analysis of variance, the significant factors that affected the experimental design responses were also identified. The predicted stability parameters using the RSM and ANNs were compared using figures and tables. It is shown that the trained ANN outperformed the RSM in terms of accuracy and prediction of obtained results.
Worttrennung am Zeilenende
Authors: Neef Martin
Published: May 2013

Word division at ends of lines is a part of the official orthography of German. In the present text, it is identified as being codified in three different ways: First by a general rule that makes recourse to spoken syllables, second by a set of more specific rules that deal with several different patterns, some of them failing to follow the syllable rule, and third by explicit markings in each individual entry in dictionaries like Duden (2006). Some of these data are inconsistent with the aforesaid rule systems. Based on a theory that is formulated independently of the subject of this article, namely the recoding model of graphematics (Neef 2005a), the different sets of data of word division are reconstructed in a theoretical model. As a result it is argued that word division is guided by properties of letters in the first place, while in a secondary fashion the system is disturbed by a syllabic conception. A pure syllablebased explanation that is advocated for in several other theoretical analyses, however, fails to cover central aspects of the data
Skripte. Konturen einer Konzeption
Authors: Ludwig Otto
Published: May 2013

Abstract The essay discusses a conceptual differentiation. It deals with the distinction of texts and scripts. Script is the generic term for manuscripts, typoscripts and compuscripts. What we have in our hands, if we take a book out of the shelf, is a copy of a script. What we are interested in and what we are trying to comprehend is the text represented in the script.

Initially the distinction is exemplified. Thereafter the conception of the script is differentiated with regard to functions, graphic means and constituents (like letters, lines, non line-bounded representations, pages and the scripts as a whole). Next the effects upon each other, the influence of the script upon the composition as well as the impact of the texts on the organisation of scripts, are discussed. The essay concludes with a theoretical assignment.
HPA axis changes during the initial phase of psychosocial stressor exposure in male mice
Authors: Uschold-Schmidt Nicole , Peterlik Daniel , Füchsl Andrea M , Reber Stefan O
Published: May 2013

Chronic subordinate colony (CSC) housing for 19 days results in unaffected basal morning corticosterone (CORT) levels despite a pronounced increase in adrenal mass, likely mediated by an attenuation of adrenal corticotropin (ACTH) responsiveness. Given that the pronounced increase in basal morning plasma CORT levels returns to baseline as early as 48 h after the start of CSC, it is likely that the attenuated ACTH responsiveness develops already during this initial phase. This was tested in the present study. In line with previous findings, basal morning plasma CORT levels were elevated following 10 h, but not 48 h, of CSC exposure. Basal morning plasma ACTH concentrations and relative in vivo adrenal CORT content were increased following 10 h and to a lesser extent following 48 h of CSC exposure, positively correlating. Relative in vitro adrenal CORT secretion in response to ACTH (100 nM) and kidney protein expression of 11β-hydroxysteroid dehydrogenase type 2 (HSD11B2) were unaffected following both time points. Adrenal mRNA expression of key steroidogenic enzymes was unaffected/decreased following 10 h and unaffected/increased following 48 h of CSC exposure. Together, our findings suggest that basal plasma hypercorticism during the initial CSC phase is mainly prevented by an attenuation of pituitary ACTH release. An increased absolute adrenal weight following 10 h, but not 48 h, of CSC exposure indicates that restoration of normal adrenal mass also adds to a lesser extent to prevent basal hypercorticism. A contributing role of alterations in enzymatic CORT degradation and steroidogenic enzyme availability is likely, but has to be further addressed in future studies.
Cyclic loading behaviour of reinforced soil–aggregate bases
Authors: Nair Asha Manomohan , Latha G. Madhavi
Published: May 2013

The behaviour of unreinforced and geosynthetic-reinforced soil aggregate systems under cyclic loading is studied in this paper to understand the beneficial effect of geosynthetic reinforcement in unpaved road subgrades through laboratory experiments. Soil–aggregate systems were prepared in a 300 mm diameter mould by compacting clay of low plasticity to its maximum unit weight at optimum moisture content in equal lifts and placing a 50 mm high aggregate layer above the clay layer. In the reinforced soil–aggregate systems, a geosynthetic layer was introduced at the interface of the soil and aggregate. Three different types of reinforcement, namely a geotextile, a geogrid and a geonet, were used in the experiments. The soil–aggregate systems were subjected to specific sinusoidal cyclic loading in a displacement control mode up to 100 cycles. The results were analysed to understand the elastic and plastic strains developed in the systems and to compare the performance of the unreinforced and the various types of geosynthetic-reinforced systems. The resilient, cyclic and secant modulii of different systems were compared. Traffic benefit ratios of the unreinforced and reinforced systems were compared. It was observed that the reinforcement was beneficial in improving the load-carrying capacity and traffic benefit ratio of the soil–aggregate systems. Stiffer geogrids provided a better stress attenuation effect and thereby reduced the plastic deformations compared with the geotextile and low tensile strength grid. No significant improvement in the resilient modulus was observed by introducing reinforcement.
Reliability analysis of moment redistribution in reinforced concrete beams
Authors: Baji Hassan , Ronagh Hamid Reza
Published: May 2013

Design codes allow a limited amount of moment redistribution in continuous reinforced concrete beams and often make use of lower bound values in the procedure for estimating the moment redistribution factors. Here, based on the concept of demand and capacity rotation, and by means of Monte Carlo simulation, a probabilistic model is derived for the evaluation of moment redistribution factors. Results show that in all considered cases, the evaluated mean and nominal values of moment redistribution factor are greater than the values provided by the ACI code. On the other hand, the 5th percentile value of moment redistribution factor could be lower than those specified by the code. Although the reduction of strength limit state reliability index attributable to uncertainty in moment redistribution factors is not large, it is comparable to the reduction in reliability index resulting from increasing the ratio of live to dead load.
Strength of concrete reinforced using double-blade mixer
Authors: Yao Yunshi , Feng Zhongxu , Chen Shibin
Published: May 2013

In order to reinforce the strength of concrete, a new mixing principle by double-blade mixer is proposed and investigated. A double-blade mixer, based on an ordinary biaxial mixer, is designed and fabricated, and its mixing performances are investigated. Compared with the motion of the ordinary biaxial mixer, the double-blade mixer strengthens the radial motion of the mixture, which achieves synthesis of the circumferential forces, the axial forces and the radial forces. Compared with an ordinary biaxial mixer, in the same mixing time the strength of concrete obtained by double-blade mixer is increased by 16%. Also for the same strength of concrete using a double-blade mixer shortens the mixing time by 50% compared with that of an ordinary biaxial mixer. Moreover, when the amount of cement is reduced by 20%, the strength of concrete is increased by 17%. The experimental results prove that the double-blade mixer has obvious advantages for enhancing the strength of concrete, saving mixing time and achieving uniform mixing rapidly. Therefore, a double-blade mixer can reinforce the strength of concrete, and could be widely used in construction projects.
Grafting of continuous polypropylene fibres by methacrylic acid monomers to improve their bonding to concrete matrix
Authors: Mazhar Majid , Abdouss Majid , Shariatinia Zahra , Zargaran Mojdeh
Published: May 2013

In this paper, methacrylic acid monomers grafted to continuous polypropylene fibres to make them hydrophile, while grafting experiments are designed based on Taguchi method in which temperature, monomer concentration, cross-linker concentration and time of reaction are selected as variable factors at four levels and several polypropylene fibres with various grafting degrees are obtained. Next, pull-out behaviour of modified fibres embedded to concrete is investigated and compared to raw fibres. In addition, influence of grafting on pull-out behaviour of fibres is addressed. Pull-out tests and scanning electron microscopy images verified the bonding improvement of the proposed fibres to concrete appropriately. Finally, optimum grafting degree to achieve the best bonding between the fibres and concrete with highest tolerated tensile load is determined.
Water and wastewater management in the treatment process of a Roman fullonica
Authors: De Feo G. , De Gisi S.
Published: May 2013

The aim of this paper is to study the treatment process of a Roman fullery (fullonica) with particular attention to the water and wastewater management system. Remains of several fullonicae have been documented at Pompeii and Herculaneum (Campania, Southern Italy), Ostia and Rome (Latium region, Central Italy), Florence (Tuscany, Central Italy), etc. The common academic perception of Roman fullonicae is significantly influenced by the fullonica of Stephanus (I 6, 7) in Pompeii, which is assumed to be a paradigmatic case study in this paper. The use of urine as an alkaline chemical agent in the soaping phase of the filling treatment process was overstated, with there also being no evidence of the fact that fullers collected their urine by means of vessels in front of their workshops, as usually reported. Thus, it is not clear how the Roman fullers collected and transported the urine they used in the fulleries. Finally, the rinsing phase can be considered a clear example of water reuse.
Water supply methods in Ancient Thera: the case of the sanctuary of Apollo Karneios
Authors: Bitis Ioannis
Published: May 2013

The same natural water sources which enabled people to settle the island of Thera in the 8th century BC, are still visible today on the hill of Mesa Vouno. An extensive infrastructure for the exploitation of rainwaters was established in the city of Ancient Thera on Mesa Vouno, which is striking for the quality of its construction as well as the inventiveness of its builders. Rainwater followed the course that was prescribed for its storage from the flat rooftops to underground cisterns. The water on the roof of the temple of Apollo Karneios followed a comparable route, the study of which answered many questions regarding a false – as it turned out – reconstruction of the temple plan. The above study is completed by the production of an axonometric visual reconstruction of the temple.
Reduction of Escherichia coli bacteria from contaminated water by combining hydrogen peroxide, ozone and ultraviolet light
Authors: Tawabini Bassam , Khalil Amjad , Abussaud Basim
Published: May 2013

This study demonstrates the reduction of Escherichia coli bacteria from contaminated water when the water is treated with advanced oxidation processes utilising the following combinations: hydrogen peroxide (H2O2) and ozone (O3), ultraviolet light (UV) and hydrogen peroxide (H2O2), and ultraviolet light (UV) and ozone (O3). Approximately 1 × 108cell/mL of E. coli were spiked into water samples contaminated with 500 ppb of methyl tertiary butyl ether (MTBE) and benzene. Water samples were then treated in a bench-scale photoreactor using 15 W low pressure (LP) and 150 W medium pressure (MP) UV lamps. Hydrogen peroxide at 20, 50 and 100 ppm and ozone at 1, 2 and 5 ppm were used along with the UV irradiation to generate the hydroxyl radicals (.OH) needed to degrade organic contaminants such as MTBE and benzene and most likely destroy bacteria. The results of the study showed that, under the study conditions, no effect of benzene or MTBE was observed on the inactivation rate of the bacteria. Moreover, results showed that the combined effect of the LP 15 W UV lamp with 2 ppm O3 or with 50 ppm H2O2 showed the highest inactivation rate of bacteria within 5 min. The H2O2/O3 process showed high disinfection capability at high dosages of peroxide (50 ppm) and O3 (2 and 5 ppm).
Total volatile solids may aid in trophic state assessment in subtropical reservoirs
Authors: Pena L. S. F. , Calijuri M. d. C. , Cunha D. G. F.
Published: May 2013

Brazilian artificial reservoirs are multi-purpose systems of great importance for the community since they are used for drinking water supply, energy generation and agricultural irrigation. Anthropogenic eutrophication is an environmental problem of special concern because it can restrict water use due to aquatic systems deterioration. Therefore, trophic state prediction is an important tool for the rapid detection of water quality decrease and the identification of priority areas where action is needed. Within this context, the aim of this research was to assess the role of TVS (total volatile solids) in predicting the trophic status of subtropical reservoirs. To achieve this goal, four stations in the Itupararanga Reservoir (São Paulo State, Brazil) were sampled during dry, intermediate and rainy periods to determine total suspended solids concentrations in different depths of the water column, in addition to other variables (e.g. phosphorus, nitrogen, chlorophyll-a). Through a linear regression between TSI (trophic state index) and the TVS concentrations, an equation relating these two variables was generated (R2 = 0.67). New TSI values (named TSIcalc) were calculated and analyzed against the observed ones (TSIobs, determined through the total phosphorus and chlorophyll-a concentrations). The results suggested that TVS may be considered an interesting variable to predict the trophic state of subtropical reservoirs.
The biological safety of distribution systems following UV disinfection in rural areas in Beijing, China
Authors: Sun Wenjun , Liu Wenjun , Cui Lifeng , Liu Leibin
Published: May 2013

In rural areas, UV disinfection has a great potential for drinking water treatment because of the ability to achieve target disinfection levels and the ease of operation and maintenance; however, UV disinfection provides no disinfection residual to the water distribution system. This study examines the biological safety of rural water distribution systems following UV disinfection. The results showed that in all the tested villages, heterotrophic plate counts (HPC) were below 500 colony-forming units (CFU)/mL and total bacterial counts (TBC) were below 100 CFU/mL. Both meet the drinking water standard in China. The HPC concentration was related to the water temperature, the assimilable organic carbon (AOC) and water distribution system conditions. Total coliforms were detectable at some water distribution system sampling points in two out of eight villages.
Major urban water and wastewater systems in Minoan Crete, Greece
Authors: Angelakis A. N. , Spyridakis S. V.
Published: May 2013

During the Minoan era a number of remarkable developments occurred on the Greek island of Crete which have been widely recognized. However, one of the salient characteristics was the architectural and hydraulic function of its water supply, sewerage, and drainage systems in the Minoan palaces, cities, and other settlements. It might be inferred, therefore, that Minoan master craftsmen in Bronze Age Crete were aware of some of the basic principles of what we call today water and environmental technologies. The scope of this study is the presentation of the most characteristic examples of extant hydraulic works and related hydro-technologies in Minoan Crete. During Minoan times the focus of water management was on sustainable, small-scale safe, cost-efficient and environmentally-friendly practices which might be relevant today, as the water supply and wastewater management problems of modern societies are not very different from those faced by Minoans.
Separation of digoxin by luiquid-luiquid extraction from extracts of foxglove secondary glycosides
Authors: Novkovic Vesna , Stanojevic Ljiljana , Cakic Milorad , Veljkovic Vlada , Stankovic Mihajlo
Published: May 2013

The present study deals with the extraction of digoxin (Dgx) from chloroform
and trichloroethylene extracts of the secondary glycosides of fermented
foxglove (Digitalis lanata Ehrh.) foliage by liquid-liquid extraction. The
extraction degree (ED) of Dgx achieved by maceration and percolation using
10% vol. aqueous ethanol solutions were higher than 95%. Using
trichlorethylene and chloroform, the ED of Dgx of about 100% and 96%,
respectively from the liquid ethanolic extracts (macerate or percolate) were
achieved by the four-cycle extraction. Fifteen separating funnels were
employed for the liquid-liquid extraction. Three different four-component
two-phase systems (ethanol:water - chloroform:ethyl acetate, ethanol:water -
chloroform:trichloroethylene and ethanol:water - trichloroethylene:ethyl
acetate) were tested as an extracting solvent to get the final product
having more than 98% of Dgx. The initial amount of the chloroform or
trichloroethylene extract in the light phase was varied between 5 and 25
g/L, while the volume ratio of light and heavy phases was in the range of
1:1 to 1:2. The best Dgx yield of 98% was achieved with the system
ethanol:water - chloroform:trichloroethylene 35:15:20:30 at the volume ratio
of the phases of 1:1.1 and at the initial amount of the extract of 15 g/L.
Purity of the separated digoxin was 99.8 %.
Preparation of potassium nitrate from potassium chloride and magnesium nitrate in a laboratory scale using industrial raw materials
Authors: Jurišová Jana , Fellner Pavel , Danielik Vladimír , Lencsés Marek , Králik Milan , Šípoš Rastislav
Published: May 2013

Preparation of potassium nitrate from magnesium nitrate and potassium chloride was investigated. Prepared potassium nitrate contains less than 0.5 % chlorides and it can be applied as environmentally friendly fertilizer in hydroponic systems. After filtration out potassium nitrate crystals from the reciprocal system K+, Mg2+//Cl-, NO3- - H2O, the mother liquor still contains reasonable amount of potassium cations. By evaporation of the mother liquor, carnallite (MgCl2・KCl・6H2O) with admixture of MgCl2・6H2O crystallizes out. Decomposition of carnallite with cold water makes it possible to separate potassium chloride from this compound. When this KCl is returned back to the process of KNO3 making, utilization of potassium as high as 97 % can be achieved.
Protective membranes at electrochemical biosensors
Authors: Ambrózy Anton , Hlavatá Lenka , Labuda Ján
Published: May 2013

The primary role of the biosensor is to specifically detect an analyte using biochemical reaction or interaction mediated by isolated biomolecules, organelles, whole cells or biomimetic receptors. In terms of construction and function, the biosensor consists of biorecognition element and transducer connected to suitable measurement device. Electrochemical biosensor is an electrode or microelectrode with the surface chemically modified by the biorecognition element. The main problem of analysis with the biosensors is the presence of low and high molecular weight substances in the sample that interfere at the detection of analyte. Due to deposition of surface active compounds the biosensor response may be diminished depending on time of interaction with sample. These effects can be eliminated by using anti-interference membranes. This review deals with preparation and utilization of membranes for the biocomponent immobilization and with outer-sphere protective membranes.
Secondary metabolite production of Epicoccum sp. isolated from lignite
Authors: Kaliňák Michal , Barátová Viera , Gallová Emília , Ondrušová Zuzana , Hudecová Daniela
Published: May 2013

We have extracted secondary metabolites from fossil fungus Epicoccum sp. isolated from lignite and characterized changes in production on various growth media. Chromatographic separation yielded more than 7 fractions that were characterized spectroscopically. One secondary metabolite showed antimicrobial activity. Peaks in the NMR spectra of isolated fractions differ from compounds described in literature that were isolated from recent strains of Epicoccum. The remaining water phase after the extraction was shown to have protein staining properties and could be also used for fluorescent viability stain of yeast cells.
Therapeutic potential of curcumin in medicinal chemistry
Authors: Košťálová Daniela , Bezáková Lýdia , Račkovác Lucia , Mošovská Silvia , Šturdík Ernest
Published: May 2013

Extensive research over the past half century has shown that curcumin (diferuloylmethane), a polyphenolic compound of turmeric (Curcuma longa L.), can modulate multiple cell signaling pathways. Extensive clinical trials have addressed the pharmacokinetics, safety, and efficacy of this nutraceutical against numerous diseases in human. Curcumin, known for thousand years as a subject of Ayurvedic medicine, has undergone in recent times remarkable transformation into a drug candidate with prospective multipotent therapeutic application. Characterized by high chemical reactivity, resulting from an extended conjugated double bond system prone to nucleophilic attack, curcumin has been shown to interact with a plethora of molecular targets, in numerous experimental observations. In clinical trials, has been used either alone or in combination with other agent. However, its clinical advance has been limited by its short biological half-life, fast metabolism and poor systemic bioavailability after oral administration. To mitigate the above limitations, recently various formulation of curcumin, including nanoparticles, micelles, liposomes, phytosomes delivery system has been examined. The present review has been devoted towards better understanding of the phytonutraceutic properties of curcumin and turmeric based on their disease specific indications and enhancing their prophylactic and therapeutic nutraceutical qualities. The article deals with the biological activity, mode of action, toxicity and forthcoming application of these leads.
New detector tube for the detection of nitrite in water
Authors: Pitschmann Vladimír , Kobliha Zbyněk , Tušarová Ivana , Vetchý David
Published: May 2013

A new colorimetric detector tube for the detection of trace concentrations of nitrite in water was developed. The detector tube is based on a diazo coupling reaction of nitrite with dapsone and N-(1-naphthyl) ethylenediamine dihydrochloride during the formation of red-violet azo dye. Spherical granules (pellets) made from the composite material were used as the carrier of chemical reagents. They were prepared by pelletizing the mixture of microcrystalline cellulose, lactose, kaolin and polyvinylpyrrolidone. Colouring is done on a layer of silica gel impregnated with citric acid. The detector tube is highly sensitive, selective and stable when stored. The detection limit is 0.1 μg.ml-1, i.e. 0.03 μg.ml-1 N(NO2 -). The optimal measuring range of nitrite concentration in the analyzed sample ranges from 0.5 to 80 μg.ml-1, i.e. 0.15-24.36 μg.ml-1 N(NO2 -). The detector tube can easily be structurally modified for analysis of nitrates with a detection limit of 1 μg/ml-1, i.e. 0.23 μg.ml-1 N(NO3 -).
Calcium hydroxide: An efficient and mild base for one-pot synthesis of curcumin and it’s analogues
Authors: Kulkarni Pramod S. , Kondhare Dasharath D. , Varala Ravi , Zubaidha Pudukulathan K.
Published: May 2013

Calcium hydroxide was found to be an efficient mild base for the one-pot synthesis of curcumin and its analogues obtained by condensation of one equivalent of acetyl acetone with two equivalents of corresponding aromatic aldehyde. The present protocol offers various advantages such as high yields, inexpensive easily available mild base, easy workup and eco-friendly method.