bluuebunny/crossref_metadata_2025 huggingface dataset:
Sporopollenin microcapsules for microencapsulation of living cells
Authors: Hamad Shwan A. , Dyab Amro K.F. , Stoyanov Simeon D. , Paunov Vesselin N.
Published: May 2013

We used sporopollenin prepared from Lycopodium Clavatum to encapsulate living yeast cells as a model for probiotics. The microencapsulation of cells was achieved by using the trilite scars of the sporopollenin microcapsules which can open up by compressing the sporopollenin into a pellet. Such compressed pellets were exposed to an aqueous suspension of yeast cells in the presence of a biocompatible surface active agent which allowed living cells to be loaded inside the sporopollenin particles by the influx of liquid to the sporopollenin interior as the deformed microcapsules re-inflated to their original state. We demonstrated that the cells viability and biological activity is preserved after the microencapsulation in the sporopollenin. Such microencapsulation technology could find application in preserving cells from mechanical stress and aggressive environments which can be used in protection of probiotics in food formulations.
Resource limitation in a competitive context determines complex plant responses to experimental resource additions
Authors: Farrior Caroline E. , Tilman David , Dybzinski Ray , Reich Peter B. , Levin Simon A. , Pacala Stephen W.
Published: May 2013

Almost all models of plant resource limitation are grounded in either one or both of two simple conceptual models: Liebig's Minimum Hypothesis (LMH), the idea that plants are limited by the resource in shortest supply, and the Multiple Limitation Hypothesis (MLH), the idea that plants should adjust to their environment so that all essential resources are equally limiting. Despite the differences in their predictions, experiments have so far failed to discriminate between them. In a simple factorial nitrogen and water addition experiment in a Minnesota grassland, we observed shifts in allocation that, as in previous studies, are not all explained by a single theory. We found that leaf biomass responded positively to nitrogen additions but did not respond to water additions. We found that fine‐root biomass increased in response to water additions, but only at low nitrogen levels, and that fine‐root biomass decreased in response to nitrogen additions, but only at high water levels.

To understand these responses we built a physiologically based model of plant competition for water, nitrogen, and space to predict plant allocation to fine roots and leaves. Critically, we include in our model the inherent variability of soil moisture and treat light, water, and nitrogen as resources with distinct mechanistic roles. Experimental results showed that plants were nitrogen and water limited. The model explains the experimental results, under conditions of co‐limitation, as follows. Foliage increases with nitrogen additions but not water additions because leaf construction is constrained by nitrogen uptake. When water is added, plants spend a larger fraction of the growing season limited by light (and effectively nitrogen) than by water. Thus, water additions cause fine‐root biomass to increase because of the increased importance of nitrogen limitation. The response of fine‐root biomass to water additions decreases with nitrogen additions because these additions reduce nitrogen limitation. In general, our results are explained by sequential resource limitation. The rate of carbon assimilation may be limited by a single resource at any one moment, but the identity of the limiting resource(s) changes throughout the growing season.
Terrestrial distribution of pond‐breeding salamanders around an isolated wetland
Authors: Scott David E. , Komoroski Mark J. , Croshaw Dean A. , Dixon Philip M.
Published: May 2013

Terrestrial habitats surrounding isolated wetlands are a critical resource for many pond‐breeding amphibian species, yet few studies have examined the terrestrial distribution of post‐metamorphic juveniles and adults. We used an encircling drift fence at a breeding pond in conjunction with partial fences at 90, 172, and 332 m from the wetland to estimate the terrestrial distribution of adult marbled salamanders (Ambystoma opacum; four breeding seasons) and mole salamanders (A. talpoideum; two seasons), as well as the dispersion of newly metamorphosed A. opacum (one summer). For newly metamorphosed A. opacum, 79% emigrated <90 m from the wetland, and 8% moved beyond 172 m; movement distance was unrelated to body size. Distribution of adult A. opacum varied among years, with an average of 28% (range 23–31%) occurring beyond 172 m in all years. Averaged across two years, 51% of adult A. talpoideum occurred beyond 172 m. Lognormal models provided a good fit to both the juvenile and adult ambystomatid distributions, and parameters differed between age classes, sexes, species, and years within species. For adult A. opacum a buffer radius of 300 m or 340 m, depending on the year, is estimated to include 95% of adults; for A. talpoideum the estimate is 464 m or 501 m. A reanalysis of distribution data for seven ambystomatid species shows that a previous estimate of a 164‐m radius to protect 95% of a population underestimates the needed buffer radius by 185 m. Because our study wetland requires a nearly 500 m wide radius to protect 95% of its ambystomatid adults, preservation of similar communities may require much more surrounding terrestrial habitat than previously thought.
Characterizing scale‐dependent community assembly using the functional‐diversity–area relationship
Authors: Smith Adam B. , Sandel Brody , Kraft Nathan J. B. , Carey Susan
Published: May 2013

Phenotypic traits mediate organisms' interactions with the environment and determine how they affect and are affected by their biotic and abiotic milieu. Thus, dispersion of trait values, or functional diversity (FD) of a community can offer insights into processes driving community assembly. For example, underdispersion of FD suggests that habitat “filtering” of species with unfavorable trait values restricts the species that can exist in a particular habitat, while even spacing of FD suggests that interspecific competition, or biotic “sorting,” discourages the coexistence of species with similar trait values. Since assembly processes are expected to vary as a function of spatial scale, we should also expect patterns of FD to reflect scale dependence in filtering and biotic sorting. Here we present the concept of the functional‐diversity–area relationship (FAR), which is similar to the species–area relationship but plots a measure of phenotypic trait diversity as a function of spatial scale. We develop a set of null model tests that discriminate between FARs generated predominantly by filtering or biotic sorting and indicate the scales at which these effects are pronounced. The utility of the FAR for addressing long‐standing issues in ecology is illustrated with several examples. A multi‐scale examination of FD and its pattern relative to null expectations provides an important tool for ecologists interested in understanding the scale dependence of community assembly processes.
Accommodating species identification errors in transect surveys
Authors: Conn Paul B. , McClintock Brett T. , Cameron Michael F. , Johnson Devin S. , Moreland Erin E. , Boveng Peter L.
Published: May 2013

Ecologists often use transect surveys to estimate the density and abundance of animal populations. Errors in species classification are often evident in such surveys, yet few statistical methods exist to properly account for them. In this paper, we examine biases that result from species misidentification when ignored, and we develop statistical models to provide unbiased estimates of density in the face of such errors. Our approach treats true species identity as a latent variable and requires auxiliary information on the misclassification process (such as informative priors, experiments using known species, or a double‐observer protocol). We illustrate our approach with simulated census data and with double‐observer survey data for ice‐associated seals in the Bering Sea. For the seal analysis, we integrated misclassification into a model‐based framework for distance‐sampling data. The simulated data analysis demonstrated reliable estimation of animal density when there are experimental data to inform misclassification rates; double‐observer protocols provided robust inference when there were “unknown” species observations but no outright misclassification, or when misclassification probabilities were symmetric and a symmetry constraint was imposed during estimation. Under our modeling framework, we obtained reasonable apparent densities of seal species even under considerable imprecision in species identification. We obtained more reliable inferences when modeling variation in density among transects. We argue that ecologists should often use spatially explicit models to account for differences in species distributions when trying to account for species misidentification. Our results support using double‐observer sampling protocols that guard against species misclassification (i.e., by recording uncertain observations as “unknown”).
A complex relationship between moonlight and temperature on the foraging behavior of the Alabama beach mouse
Authors: Falcy Matthew R. , Danielson Brent J.
Published: May 2013

Most animal species forage with risk from an ensemble of predators, wherein some predators are themselves prey to the others. A forager's behavior should reflect a synthesis of the effect of environmental conditions on both marginal predation risk and rates of energy accumulation. Here, a forager's giving‐up density [GUD] is analyzed for signs of these complex signals. Specifically, we hypothesized that temperature can reverse the effect of moonlight intensity on Alabama beach mouse (Peromyscus polionotus ammobates) GUD because changes in temperature change the ensemble of predators from homeothermic taxa with better vision than the mouse to ectothermic taxa with worse vision than the mouse. We fit several models to GUD measurements taken over a broad range of temperatures and nocturnal luminosities. We obtained strong information‐theoretic support for a model that is consistent with our hypothesis of temperature‐dependent reversal of the effect of nocturnal illumination on mouse GUD. Signals in GUDs can reveal complex effects of optimal foraging at multiple trophic levels, which is especially informative when direct measurement of taxonomic sources of predation is not feasible.
A safety network against regional population collapse: mature subpopulations in refuges distributed across the landscape
Authors: Jack Lucy , Wing Stephen R.
Published: May 2013

Theory suggests that marine reserve networks can maintain wide geographical distributions of exploited fish and invertebrates. Since 2005, ten regions in southwest New Zealand have been designated no‐take marine reserves nested within eleven commercial fishing exclusion zones. We observed increases in abundance of rock lobster (Jasus edwardsii) and blue cod (Parapercis colias) from 2002–2010 within some marine reserves, but not in the other management zones. Mature size distributions of rock lobsters were only observed within protected areas. Model based inference ranked environmental descriptors versus area under protection in explaining abundance and changes in abundance observed within marine reserves and indicated that J. edwardsii became most abundant in larger marine reserves, but only under specific environmental conditions. P. colias became most abundant in large marine reserves, particularly those with larger buffers against commercial fishing. Analysis of population changes for both species across Fiordland since implementation of the reserve network (2006–2010) indicated that marine reserves resulted in either increases in, or maintenance of abundance in the face of regional declines. We highlight the potential effectiveness of networks of marine reserves in maintaining subpopulations with high abundance and mature size structure across large geographical areas, particularly if key criteria are incorporated.
Bone Formation Under the Elevated Sinus Membrane Using Venous Coagulum
Authors: Beaudry Kathleen A. , Geurs Nicolaas C. , Lemons Jack E. , Reddy Michael S.
Published: May 2013

Introduction: Insufficient bone height is a common obstacle to placing dental implants in the posterior maxilla. Sinus grafts have been shown to be a highly predictable way to increase bone height in the posterior maxilla. This case series illustrates a technique using venous coagulum and simultaneous implant placement under the elevated sinus. Bone formation is demonstrated clinically, radiographically, and histologically. To the best of our knowledge, this is the first report of histomorphometric results and microcomputed tomography (micro‐CT) using this technique.

Case Series: A total of five sinus elevations with simultaneous placement of two dental implants were performed with venous blood coagulum as the sole filling biomaterial. At the time of uncovering, after 8 to 9 months of healing, biopsies were harvested from the lateral wall of the maxilla. This study illustrates bone formation under five elevated sinuses, with simultaneous placement of dental implants, using venous coagulum as the sole filling material. Results showed significant gains in bone height adjacent to the implant. Micro‐CT showed well‐structured trabecular bone. Histomorphometry of biopsies showed 38% to 74% vital bone.

Conclusions: This case series illustrates that bone‐grafting materials in the subsinus cavity are not required for successful placement of implants. Use of one's own blood as filling material removes any objections to grafting, including religious, ethical, or fear of disease transmission. Venous coagulum is a simple, inexpensive biomaterial, and its systematic use during a sinus lift may be a relevant option, ultimately leading to increased access to implant treatment options for patients.
Influence of Tapered and External Hexagon Connections on Bone Stresses Around Tilted Dental Implants: Three‐Dimensional Finite Element Method With Statistical Analysis
Authors: de Faria Almeida Daniel Augusto , Pellizzer Eduardo Piza , Verri Fellippo Ramos , Santiago Joel Ferreira , de Carvalho Paulo Ségio Perri
Published: May 2013

Background: The purpose of this study is to analyze the tension distribution on bone tissue around implants with different angulations (0°, 17°, and 30°) and connections (external hexagon and tapered) through the use of three‐dimensional finite element and statistical analyses.

Methods: Twelve different configurations of three‐dimensional finite element models, including three inclinations of the implants (0°, 17°, and 30°), two connections (an external hexagon and a tapered), and two load applications (axial and oblique), were simulated. The maximum principal stress values for cortical bone were measured at the mesial, distal, buccal, and lingual regions around the implant for each analyzed situation, totaling 48 groups. Loads of 200 and 100 N were applied at the occlusal surface in the axial and oblique directions, respectively. Maximum principal stress values were measured at the bone crest and statistically analyzed using analysis of variance. Stress patterns in the bone tissue around the implant were analyzed qualitatively.

Results: The results demonstrated that under the oblique loading process, the external hexagon connection showed significantly higher stress concentrations in the bone tissue (P <0.05) compared with the tapered connection. Moreover, the buccal and mesial regions of the cortical bone concentrated significantly higher stress (P <0.005) to the external hexagon implant type. Under the oblique loading direction, the increased external hexagon implant angulation induced a significantly higher stress concentration (P = 0.045).

Conclusions: The study results show that: 1) the oblique load was more damaging to bone tissue, mainly when associated with external hexagon implants; and 2) there was a higher stress concentration on the buccal region in comparison to all other regions under oblique load.
Vitamin E Supplementation, Superoxide Dismutase Status, and Outcome of Scaling and Root Planing in Patients With Chronic Periodontitis: A Randomized Clinical Trial
Authors: Singh Neha , Chander Narula Satish , Kumar Sharma Rajinder , Tewari Shikha , Kumar Sehgal Paramjeet
Published: May 2013

Background: This study investigates the levels of superoxide dismutase (SOD) activity in serum and saliva of patients with chronic periodontitis (CP). In addition, the outcome of scaling and root planing (SRP) with and without vitamin E supplementation is evaluated in terms of changes in periodontal parameters and SOD activity in patients with CP.

Methods: Serum and salivary SOD activity in 38 patients with CP were compared with those of 22 systemically and periodontally healthy individuals (control group). At periodontal examination, serum and saliva samples were obtained. Patients with CP were randomly divided into treatment groups 1 (TG‐1) and 2 (TG‐2). SRP was performed for both groups, and TG‐2 also received 200 mg (300 IU) vitamin E every other day. Periodontal parameters and SOD activity were evaluated after 3 months. SOD activity was determined using an SOD assay and enzyme‐linked immunosorbent assay reader at 450 nm.

Results: SOD activity in both serum (P <0.05) and saliva (P <0.001) was lower in patients with CP compared with controls. After 3 months of follow‐up, SOD activity improved in both treatment groups; however, the improvement in TG‐2 was higher than in TG‐1, along with more improvement in periodontal parameters. Serum SOD levels in TG‐2 increased even above the level of the control group.

Conclusions: Systemic and local SOD levels are lowered in CP. Adjunctive vitamin E supplementation improves periodontal healing as well as antioxidant defense.
Antibiotic Resistance in Human Chronic Periodontitis Microbiota
Authors: Rams Thomas E. , Degener John E. , van Winkelhoff Arie J.
Published: May 2013

Background: Patients with chronic periodontitis (CP) may yield multiple species of putative periodontal bacterial pathogens that vary in their antibiotic drug susceptibility. This study determines the occurrence of in vitro antibiotic resistance among selected subgingival periodontal pathogens in patients with CP.

Methods: Subgingival biofilm specimens from inflamed deep periodontal pockets were removed before treatment from 400 adults with CP in the United States. The samples were cultured, and selected periodontal pathogens were tested in vitro for susceptibility to amoxicillin at 8 mg/L, clindamycin at 4 mg/L, doxycycline at 4 mg/L, and metronidazole at 16 mg/L, with a post hoc combination of data for amoxicillin and metronidazole. Gram‐negative enteric rods/pseudomonads were subjected to ciprofloxacin disk‐diffusion testing.

Results: Overall, 74.2% of the patients with CP revealed subgingival periodontal pathogens resistant to at least one of the test antibiotics. One or more test species, most often Prevotella intermedia/nigrescens, Streptococcus constellatus, or Aggregatibacter actinomycetemcomitans, were resistant in vitro to doxycycline, amoxicillin, metronidazole, or clindamycin, in 55%, 43.3%, 30.3%, and 26.5% of the patients with CP, respectively. Fifteen percent of patients harbored subgingival periodontal pathogens resistant to both amoxicillin and metronidazole, which were mostly either S. constellatus (45 individuals) or ciprofloxacin‐susceptible strains of Gram‐negative enteric rods/pseudomonads (nine individuals).

Conclusions: Patients with CP in the United States frequently yielded subgingival periodontal pathogens resistant in vitro to therapeutic concentrations of antibiotics commonly used in clinical periodontal practice. The wide variability found in periodontal pathogen antibiotic‐resistance patterns should concern clinicians empirically selecting antibiotic treatment regimens for patients with CP.
Intracellular Adhesion Molecule‐1 Is Regulated by Porphyromonas gingivalis Through Nucleotide Binding Oligomerization Domain‐Containing Proteins 1 and 2 Molecules in Periodontal Fibroblasts
Authors: Liu Jianru , Duan Jinyu , Wang Yixiang , Ouyang Xiangying
Published: May 2013

Background: The mechanism by which Porphyromonas gingivalis regulates intracellular adhesion molecule 1 (ICAM‐1) expression in human periodontal ligament cells (hPDLCs) and human gingival fibroblasts (hGFs) is unknown. The aim of this study is to investigate whether nucleotide binding oligomerization domain‐containing protein (NOD) 1 and NOD2 are involved in this process and the clinical significance of ICAM‐1 in periodontitis.

Methods: hPDLCs and hGFs were treated with P. gingivalis, l‐Ala‐γ‐d‐glutamyl‐mesodiaminopimelic acid (an agonist for NOD1), and muramyl dipeptide (an agonist for NOD2). Alternatively, cells transfected with small interfering RNA targeting NOD1and NOD2 were treated with P. gingivalis. ICAM‐1, NOD1, and NOD2 were detected at mRNA and protein levels. In addition, clinical examinations were performed in 30 healthy controls and 40 patients with chronic periodontitis (CP) before and after treatment, and serum‐soluble ICAM‐1 (sICAM‐1) levels in these individuals were detected by enzyme‐linked immunosorbent assay.

Results: This study shows that P. gingivalis caused an increase in ICAM‐1, NOD1, and NOD2 expression in periodontal fibroblasts. There was a linear correlation between ICAM‐1 and NOD1 and NOD2 levels. Activation of NOD1 and NOD2 by the specific agonist led to the upregulation of ICAM‐1, whereas knocking down NOD1 and NOD2 caused a reduction in P. gingivalis–induced ICAM‐1 production. Furthermore, sICAM‐1 levels were higher in patients with CP than in healthy controls and were positively related to the clinical periodontal parameters. After periodontal treatment, sICAM‐1 levels decreased significantly.

Conclusions: The present results indicate that sICAM‐1 levels are correlated to the severity of periodontitis. NOD1 and NOD2 mediate P. gingivalis–induced ICAM‐1 production in periodontal fibroblasts. NOD1 and NOD2 could be considered potential targets for periodontal therapy.
Growth and infrastructure investment in India: Achievements, challenges, and opportunities
Authors: Mishra Aswini , Narendra Kunapareddy , Kar Bibhu
Published: May 2013

The paper analyses the recent scenario of infrastructure investment in India,
with the recognition that inadequate infrastructure is one of the major
constraints on India?s ability to sustain high GDP growth. It conducts an
overview of the trends in infrastructure investment from the 10th Five Year
Plan onwards, and tries to examine the linkage between infrastructure and
economic growth. The results exhibit a very high rate of return and also
highlight that, since resource constraints will continue to limit public
investment in infrastructure in other areas, Public Private Partnership
(PPP) project-based development needs to be encouraged wherever feasible.
Is there a structural improvement in the merchandise exports of the Balkan countries in the period 2000-2012?
Authors: Nikolic Goran
Published: May 2013

The value of indicators of the similarity of Balkan countries? export and
import structures to those of developed countries grew only mildly, which
indicates that the unfavourable structure of exports has been retained. While
similarity coefficients increased in the period until and including 2012,
they failed to reach a critical turning point as in advanced European
countries in transition. In practically all Balkan economies, since 2000 the
technological intensity and the factor intensity of foreign trade have
changed toward an increased share of highly-processed products, but the share
of skill-intensive manufactures remained almost two times smaller than in
developed economies. An aggravating factor was the continual strong
double-digit growth of exports in most Balkan countries, which ? forced?
exports based on the existing inappropriate structure and prevented a change
in export structure. Balkan countries would have to attract FDI in export
sectors that are capital- or skilled labour- intensive. A targeted industrial
policy and sector- and firm-level strategies are necessary to give momentum
to a shift towards technology-intensive activities, associated with higher
spillover effects. It is realistic to expect that the evolution of the
economic system through restructuring would additionally improve the still
unfavourable structural characteristics of Balkan countries? exports.
Taxation and forms of organizing business activities
Authors: Djindjic Srdjan
Published: May 2013

This paper takes sample tax regimes and tendencies from the developed
countries in the EU-15 and the USA, and uses them to analyse the influence of
taxation on the choice of organizational form of profit-oriented entities in
Serbia. In order to understand how the procedure of taxation affects the
sphere of business decision-making it is necessary to focus on the tax status
of business losses and valorization and the effects of the double taxation of
dividends. The rule of successive deduction of losses ensures the fiscally
transparent entity receives a tax saving in the form of a reduction of the
present value of the total paid tax. Meanwhile the corporation is handicapped
because it postpones loss deductions, that is, it postpones tax saving, which
directly influences the level of the present value of saved tax. The global
trend of gradually moving from the classical system towards shareholder
relief provision, above all in the form of a reduced withholding tax rate on
dividends, has two opposing features: it simplifies the tax procedure while
neglecting the distributional aims (consequences) of taxation. The analysis
of a particular practical example from the Serbian tax context enables us to
draw a conclusion in relation to the relative taxes paid by entrepreneurs
versus enterprises. The developed countries favour fiscally transparent
entities, whereas Serbia allocates tax privileges to enterprises.
Rheological properties of dough and quality of bread supplemented with emulsifying polysaccharides
Authors: Dapcevic-Hadnadjev Tamara , Dokic Ljubica , Pojic Milica , Hadnadjev Miroslav , Torbica Aleksandra , Rakita Sladjana
Published: May 2013

The aim of present study was to evaluate the effects of emulsifying starches
used as additives in breadmaking. In order to achieve this, the partial
replacement (5-10%) of wheat flour with starch sodium octenyl succinate (OSA
starch), pregelatinized starch sodium octenyl succinate (Pregel OSA starch)
and hydrolyzed spray-dried starch sodium octenyl succinate (Hydrol OSA
starch) was performed. The quality characteristics of obtained bread were
compared to control wheat flour bread and bread containing 0.5% hydroxypropyl
methylcellulose (HPMC). The obtained results indicated that addition of
Pregel and OSA starches influenced the increase in water absorption, whilst
addition of Hydrol OSA starch exhibited the opposite effect. Moreover, the
addition of all chosen starches influenced the decrease in dough stability.
On the other hand, the positive effects of implementation of emulsifying
starches on specific volume and texture were observed, where Pregel OSA and
OSA starch have expressed the highest effect.
Biodegradation of starch–graft–polystyrene and starch–graft–poly(methacrylic acid) copolymers in model river water
Authors: Nikolic Vladimir , Velickovic Sava , Antonovic Dusan , Popovic Aleksandar
Published: May 2013

In this paper the biodegradation study of grafted copolymers of polystyrene
(PS) and corn starch and poly(methacrylic acid) and corn starch in model
river water is described. These copolymers were obtained in the presence of
different amine activators. The synthesized copolymers and products of
degradation were characterized by Fourier Transform Infrared Spectroscopy
(FTIR) and Scanning Electron Microscopy (SEM). Biodegradation was monitored
by mass decrease and number of microorganisms by Koch?s method.
Biodegradation of both copolymers advanced with time, poly(methacrylic
acid)-graft-starch copolymers completely degraded after 21 day, and
polystyrene-graft-starch partially degraded (45.78-93.09 % of total mass)
after 27 days. Differences in the degree of biodegradation are consequences
of different structure of the samples, and there is a significant negative
correlation between the share of polystyrene in copolymer and degree of
biodegradation. The grafting degree of PS necessary to prevent biodegradation
was 54 %. Based on experimental evidence, mechanisms of both biodegradation
processes are proposed, and influence of degree of starch and synthetic
component of copolymers on degradation were established.
Treatment of egg processing industry effluent using chitosan as an adsorbent
Authors: Thirugnanasambandham K. , Sivakumar V. , Prakash Maran
Published: May 2013

The objective of this present study is to investigate the efficiency of
chitosan as an adsorbent to treat egg processing industry wastewater.
Parameters affecting the effluent treatment process such as pH, chitosan
dosage, settling time and initial chemical oxygen demand (COD) concentration
on the reduction percentage of turbidity, COD and biochemical oxygen demand
(BOD) were studied. Optimum condition was found to be pH of 4, chitosan
dosage of 1.1 g L-1 and settling time of 40 min respectively. The maximum
reduction percentage of turbidity, COD and BOD were found to be 94 %, 88 %
and 83 % respectively. The effective adsorption process was confirmed by
FT-IR spectra analysis. The experimental data was analyzed by different
isotherm and kinetic models. Langmuir isotherm type I model was
satisfactorily described the adsorption mechanism and the rate of COD
reduction followed the pseudo-first-order kinetic model. A four factor, three
levels Box-Behnken response surface design was employed to develop second
order polynomial mathematical models from the experimental data.
Numerical investigation on cooling performance of Ranque-Hilsch vortex tube
Authors: Pouraria Hassan , Park Warn-Gyu
Published: May 2013

A Ranque-Hilsch vortex tube (RHVT) is a mechanical device that separates a
high pressure gas stream into low pressure hot and cold streams. In this
study, four different two equation turbulence models namely the standard k-?,
RNG k-?, Realizable k-? and standard k-? models were compared to identify the
appropriate turbulence model for studying the energy separation effect in a
RHVT. Comparison between the numerical and experimental results indicates
that the standard k-? model is better than other models in predicting the
energy separation phenomenon. The distributions of temperature, pressure, and
components of velocity have been obtained in order to understand the flow
behavior inside the tube. The effect of cold outlet diameter on temperature
drop and refrigeration capacity was studied. The effect of cold mass fraction
on the movement of stagnation point and refrigeration capacity has been
investigated. Moreover, the feasibility of improving the cooling performance
of vortex tube using the cooling system was investigated. The present
numerical results revealed that using the cooling system, the net energy
transfer rate from cold inner region to the hot peripheral region increases,
thereby improving the cooling performance of the device.
Numerical study of mixed convection heat transfer in lid-driven cavity utilizing nanofluid: Effect of type and model of nanofluid
Authors: Pourmahmoud Nader , Ghafouri Ashkan , Mirzaee Iraj
Published: May 2013

Numerical investigation of the laminar mixed convection in two-dimensional
lid driven cavity filled with water-Al2O3, water-Cu or water-TiO2 nanofluids
is done in this work. In the present study, the top and bottom horizontal
walls are thermally insulated while the vertical walls are kept at constant
but different temperatures. The governing equations are given in term of the
stream function-vorticity formulation in the non-dimensionalized form and
then solved numerically by second-order central difference scheme. The
thermal conductivity and effective viscosity of nanofluid have been
calculated by Maxwell-Garnett and Brinkman models, respectively. An excellent
agreement between the current work and previously published data on the basis
of special cases are found. The governing parameters are Rayleigh number 103
? Ra ? 106 and solid concentration 0 ? ? ?0.2 at constant Reynolds and Prandtl
numbers. An increase in mean Nusselt number is found as the volume fraction
of nanoparticles increases for the whole range of Rayleigh numbers. In
addition, it is found that significant heat transfer enhancement can be
obtained by increasing thermal conductivity coefficient of additive
particles. At Ra=1.75?105, the Nusselt number increases by about 21% for
TiO2-Water, and almost 25% for Al2O3-Water, and finally around 40% for
Cu-Water nanofluid. Therefore, the highest values are obtained when using Cu
nanoparticles. The result obtained using variable thermal conductivity and
variable viscosity models are also compared to the results acquired by the
Maxwell-Garnett and the Brinkman model.
A certain analytical method used for solving the Stefan problem
Authors: Grzymkowski Radoslaw , Hetmaniok Edyta , Pleszczynski Mariusz , Slota Damian
Published: May 2013

The paper presents an analytic method applied for finding the approximate
solution of Stefan problem reduced to the one-phase solidification problem of
a plate with the unknown a priori, varying in time boundary of the region in
which the solution is sought. Proposed method is based on the known formalism
of initial extension of a sought function describing the field of temperature
into the power series, some coefficients of which can be determined with the
aid of boundary conditions, and on the approximation of a function defining
the freezing front location with the broken line, parameters of which can be
obtained by solving the appropriate differential equations. Results received
by applying the proposed procedure will be compared with the results
obtained with the aid of a classical numerical method served for solving the
Stefan problem.
Solution of the inverse heat conduction problem with Neumann boundary condition by using the homotopy perturbation method
Authors: Hetmaniok Edyta , Nowak Iwona , Slota Damian , Witula Roman , Zielonka Adam
Published: May 2013

In the paper a solution of the inverse heat conduction problem with the
Neumann boundary condition is presented. For finding this solution the
homotopy perturbation method is applied. Investigated problem consists in
calculation of the temperature distribution in considered domain, as well as
in reconstruction of the functions describing the temperature and the heat
flux on the boundary, in case when the temperature measurements in some
points of the domain are known. An example confirming usefulness of the
homotopy perturbation method for solving problems of this kind are also
included.
Numerical modeling of a turbulent semi-confined slot jet impinging on a concave surface
Authors: Ahmadi Hadi , Rajabi-Zargarabadi Mehran , Mujumdar Arun , Mohammadpour Javad
Published: May 2013

This article presents results from a numerical study of a turbulent slot jet
impinging on a concave surface. Five different low Reynolds number k-? models
were evaluated to predict the heat transfer under a two dimensional steady
turbulent jet. The effects of flow and geometrical parameters (e.g. jet
Reynolds number and jet-to-target separation distance) have been
investigated. The Yap correction is applied for reducing the over-prediction
of Nusselt number in the near wall region. It is shown that among the models
tested in this study, the LS-Yap model is capable of predicting local Nusselt
number in good agreement with the experimental data in both stagnation and
wall jet region. Moreover, after implementation of Yap correction, no
significant effect of the nozzle-to-surface distance, h/B, on the predicted
stagnation Nusselt number has been found. Finally it is demonstrated that the
higher values of turbulent Prandtl number reduces the heat diffusion along
the wall and consequently the predicted local Nusselt number is reduced
especially in the wall jet region.
Generator gas as a fuel to power a diesel engine
Authors: Tutak Wojciech , Jamrozik Arkadiusz
Published: May 2013

The results of gasification process of dried sewage sludge and use of
generator gas as a fuel for dual fuel turbocharged compression ignition
engine are presented. The results of gasifying showed that during
gasification of sewage sludge is possible to obtain generator gas of a
calorific value in the range of 2.15 ? 2.59 MJ/m3. It turned out that the
generator gas can be effectively used as a fuel to the compression ignition
engine. Because of gas composition, it was possible to run engine with
partload conditions. In dual fuel operation the high value of indicated
efficiency was achieved equal to 35%, so better than the efficiency of 30%
attainable when being fed with 100% liquid fuel. The dual fuel engine version
developed within the project can be recommended to be used in practice in a
dried sewage sludge gasification plant as a dual fuel engine driving the
electric generator loaded with the active electric power limited to 40 kW
(which accounts for approx. 50% of its rated power), because it is at this
power that the optimal conditions of operation of an engine dual fuel powered
by liquid fuel and generator gas are achieved. An additional advantage is the
utilization of waste generated in the wastewater treatment plant.
Numerical analysis of axisymmetric turbulent swirling flow in circular pipe
Authors: Cocic Aleksandar , Lecic Milan , Cantrak Svetislav
Published: May 2013

In this paper, turbulent swirling flow in circular pipe is numerically
investigated using OpenFOAM, an open-source CFD software. Flow is computed as
2D axisymmetric, with various turbulent models, but with main accent on
computations with Reynolds stress transport models. Two Reynolds stress
models were used in computations: Launder-Gibson (LG) and
Speziale-Sarkar-Gatski (SSG) models. Previous author?s experimental results
are used as a validation tool for numerical computations. It was shown that
standard two-equation models can?t predict the flow in right manner, while
the Reynolds stress models give good prediction of mean velocities. As a part of research SSG model is implemented in OpenFOAM code.
Self-similarity principle: the reduced description of randomness
Authors: Nigmatullin Raoul , Machado José , Menezes Rui
Published: May 2013

A new general fitting method based on the Self-Similar (SS) organization of random sequences is presented. The proposed analytical function helps to fit the response of many complex systems when their recorded data form a self-similar curve. The verified SS principle opens new possibilities for the fitting of economical, meteorological and other complex data when the mathematical model is absent but the reduced description in terms of some universal set of the fitting parameters is necessary. This fitting function is verified on economical (price of a commodity versus time) and weather (the Earth’s mean temperature surface data versus time) and for these nontrivial cases it becomes possible to receive a very good fit of initial data set. The general conditions of application of this fitting method describing the response of many complex systems and the forecast possibilities are discussed.
Noether’s theorem for fractional variational problems of variable order
Authors: Odzijewicz Tatiana , Malinowska Agnieszka , Torres Delfim
Published: May 2013

We prove a necessary optimality condition of Euler-Lagrange type for fractional variational problems with derivatives of incommensurate variable order. This allows us to state a version of Noether’s theorem without transformation of the independent (time) variable. Considered derivatives of variable order are defined in the sense of Caputo.
Exact solution for the fractional cable equation with nonlocal boundary conditions
Authors: Bazhlekova Emilia , Dimovski Ivan
Published: May 2013

The fractional cable equation is studied on a bounded space domain. One of the prescribed boundary conditions is of Dirichlet type, the other is of a general form, which includes the case of nonlocal boundary conditions. In real problems nonlocal boundary conditions are prescribed when the data on the boundary can not be measured directly. We apply spectral projection operators to convert the problem to a system of integral equations in any generalized eigenspace. In this way we prove uniqueness of the solution and give an algorithm for constructing the solution in the form of an expansion in terms of the generalized eigenfunctions and three-parameter Mittag-Leffler functions. Explicit representation of the solution is given for the case of double eigenvalues. We consider some examples and as a particular case we recover a recent result. The asymptotic behavior of the solution is also studied.
Riemann-Liouville and Caputo type multiple Erdélyi-Kober operators
Authors: Kiryakova Virginia , Luchko Yuri
Published: May 2013

In this paper some generalized operators of Fractional Calculus (FC) are investigated that are useful in modeling various phenomena and systems in the natural and human sciences, including physics, engineering, chemistry, control theory, etc., by means of fractional order (FO) differential equations. We start, as a background, with an overview of the Riemann-Liouville and Caputo derivatives and the Erdélyi-Kober operators. Then the multiple Erdélyi-Kober fractional integrals and derivatives of R-L type of multi-order (δ
1,…,δ
m) are introduced as their generalizations. Further, we define and investigate in detail the Caputotype multiple Erdélyi-Kober derivatives. Several examples and both known and new applications of the FC operators introduced in this paper are discussed. In particular, the hyper-Bessel differential operators of arbitrary order m > 1 are shown as their cases of integer multi-order. The role of the so-called special functions of FC is emphasized both as kernel-functions and solutions of related FO differential equations.
Existence, uniqueness and limit property of solutions to quadratic Erdélyi-Kober type integral equations of fractional order
Authors: Wang JinRong , Zhu Chun , Fečkan Michal
Published: May 2013

In this paper, we apply certain measure of noncompactness and fixed point theorem of Darbo type to derive the existence and limit property of solutions to quadratic Erdélyi-Kober type integral equations of fractional order with three parameters. Moreover, we also present the uniqueness and another existence results of the solutions to the above equations. Finally, two examples are given to illustrate the obtained results.
Numerical solution of fractional differential equations by using fractional B-spline
Authors: Jafari Hossein , Khalique Chaudry , Ramezani Mohammad , Tajadodi Haleh
Published: May 2013

In this paper, we present fractional B-spline collocation method for the numerical solution of fractional differential equations. We consider this method for solving linear fractional differential equations which involve Caputo-type fractional derivatives. The numerical results demonstrate that the method is efficient and quite accurate and it requires relatively less computational work. For this reason one can conclude that this method has advantage on other methods and hence demonstrates the importance of this work.
Lung emphysema treated successfully using volume reduction with lung sealant (AeriSeal®)
Authors: Fei Roger , Falkenstern-Ge  , Ingerl Hermann , Kohlhäufl Martin
Published: May 2013

Emphysema is a progressive and irreversible disease for which there is no cure to date. Endoscopic lung volume reduction with valve implantation or using lung sealant is a treatment option for patients with severe emphysema. A 60-year-old ex-smoker (80 pack years) referred to our center because of severe lung emphysema with progressive worsening of the obstructive ventilator pattern and clinical condition. By our patient we detected collateral channels by using the Chartis system®, which allow airflow into the target lobe and prevent atelectasis and significant lung volume reduction. Thus, we decided to treat the advanced emphysema of our patient with endoscopic volume reduction using lung sealant (AeriSeal®). The foam of lung sealant AeriSeal® is instilled into the peripheral airways and alveoli where it polymerizes and functions as tissue glue, forming a film of material on the lung surface that seals the target region to cause durable absorption atelectasis. Over a period of 16 weeks, the air within the sealed region was absorbed. The follow- up evaluation of this patient showed improved lung function (increased FEV 1, and a reduction of TLC and RV) with improved quality of life. Correlation between changes in primary and secondary outcome measures in the lung function parameters and 6- minute-walking test before and after the application of AeriSealant revealed significant reduction of hyperinflation and improvement both in the flow rates and physical capacity of our patient.
Successfully treated invasive pulmonary aspergillosis in a patient with diabetic ketoacidosis
Authors: Kumagai Ryo , Ohara Gen , Sato Shinya , Miyazaki Kunihiko , Kagohashi Katsunori , Kurishima Koichi , Satoh Hiroaki
Published: May 2013

We report herein a case of diabetic ketoacidosis associated with invasive aspergillosis that was successfully treated with liposomal amphotericin-B (L-AMB). Early intervention after confirming the diagnosis of invasive pulmonary aspergillosis is very important, and initiating early treatment with L-AMB can lead to a full recovery.
Study Habit of Post-Graduate Trainees and Residents in Medicine and Major Barriers in Achieving an Effective Training: A Multi-Institutional Survey (Preliminary Report)
Authors: Rahim Muhammad Abdur , Zaman Shahana , Amin Md. Robed , Khan Abed Hussain , Kabir Mohammad Shahjahan , Ahmed AKM Shaheen , Samad Tabassum , Ananna Mehruba Alam , Ahmed Jamal Uddin , Haque Hasna Fahmima , Dewan Pratik , Hossain Md. Delwar , Rahman Md. Raziur , Musa AKM , Uddin Khwaja Nazim
Published: May 2013

Bangladesh Journal of Medicine, Vol 24 No 1, 2013, Page 10-13 DOI: http://dx.doi.org/10.3329/bjmed.v24i1.15029
Nonalcoholic Fatty Liver Disease (NAFLD) Evaluation and Management
Authors: Perveen S , Hussain SMB , Aftab H
Published: May 2013

Bangladesh Journal of Medicine, Vol 24 No 1, 2013, Page 25-28 DOI: http://dx.doi.org/10.3329/bjmed.v24i1.15032
Professor A.E.M. Mazharul Islam
Authors: Editor The
Published: May 2013

Bangladesh Journal of Medicine, Vol 24 No 1, 2013, Page 42 DOI: http://dx.doi.org/10.3329/bjmed.v24i1.15039
Offices chantés de l'Église chrétienne orthodoxe unifiée d'Éthiopie
Authors: Damon-Guillot Anne
Published: May 2013

Cet article est centré sur le déroulement des principaux offices chantés de l’Église chrétienne orthodoxe unifiée d’Éthiopie. Cet angle d’attaque permet d’aborder, de manière relativement exhaustive, les différents éléments musicaux en œuvre dans les célébrations de l’Église d’Éthiopie. À partir d’observations faites sur le terrain, de l’analyse d’enregistrements audiovisuels, des résultats des enquêtes réalisées auprès des chantres, croisés avec la littérature existante sur le sujet, l’auteure a pu mettre à jour ce qui devrait être exécuté en célébration et ce qui l’est réellement.