bluuebunny/crossref_metadata_2025 huggingface dataset:
Durability of wheat straw ash concrete to alkali-silica reaction
Authors: Al-Akhras Nabil M.
Published: September 2012

This study investigated the effect of wheat straw ash on the durability of concrete to detrimental alkali-silica reaction. Three wheat straw ash levels were considered in the study: 5, 10 and 15% as a partial replacement of cement. The other experimental parameters investigated in the study were: w/b ratio (0·5 and 0·6) and initial curing type (moist and autoclaving). Crushed Pyrex glass was used as reactive fine aggregate in the study. After the initial curing, the concrete specimens were immersed in a 1 N NaOH solution tank at 40°C to accelerate the deleterious alkali-silica reaction. The alkali-silica reaction deterioration was assessed by measuring the expansion of concrete prisms and the reduction in compressive strength. The study showed that the wheat straw ash concrete was more durable to alkali-silica reaction damage than the control concrete. The durability of wheat straw ash concrete increased with increasing the wheat straw ash content. The wheat straw ash concrete with w/b ratio of 0·5 showed higher durability to alkali-silica reaction damage in comparison with wheat straw ash concrete with w/b ratio of 0·6. The autoclaved wheat straw ash concrete showed generally similar performance to alkali-silica reaction deterioration compared to the moist-cured wheat straw ash concrete.
Efficiency factors of recycled concrete aggregate concrete bottle-shaped struts
Authors: Singh Bhupinder , Sahoo Dipak Kumar , Bhargava Pradeep
Published: September 2012

A comparison with code-based predictions of efficiency factors of bottle-shaped struts computed using strut-and-tie models from shear test results of coarse recycled concrete aggregate concrete beams reported in the literature is presented. The objective of the comparison was to ascertain whether strut efficiency factors in current design codes originally meant for natural coarse aggregate concrete can be conservatively applied to concrete made with coarse recycled concrete aggregate or not. In addition to the codal provisions, a strut efficiency factor model developed from first principles was also used in the comparative study. The results of the comparison indicate that the AASHTO LRFD code provisions and the proposed efficiency factor model gave conservative predictions for the coarse recycled concrete aggregate concrete bottle-shaped struts although the ACI 318-08 predictions were unconservative. The most accurate predictions were obtained from the Eurocode 2 model, although with an erratic degree of conservatism. The lack of conservatism vis-à-vis the ACI code recommended strut efficiency factors does not per se indicate inferior strength of coarse recycled concrete aggregate concrete but may be attributed to the insensitivity of the ACI code efficiency factors to strut inclination with adjoining tie(s).
Use of milled waste glass in recycled aggregate concrete
Authors: Nassar Roz-Ud-Din , Soroushian Parviz
Published: September 2012

Use of milled waste glass, as partial replacement for cement, to overcome the drawbacks of recycled aggregate concrete was investigated. Based on experimental investigations of the structure and properties of concrete materials, it was found that waste glass, when milled to micro-scale particle size, undergoes pozzolanic reactions with cement hydrates, forming secondary calcium silicate hydrate (C–S–H). These reactions bring about favourable changes in the structure of the hydrated cement paste and the interfacial transition zones in normal and recycled aggregate concrete. Use of milled waste glass, as partial replacement of cement, produced significant gains in mechanical properties, dimensional stability, and abrasive effects, of recycled aggregate and normal concrete. Milled waste glass was also found to suppress alkali–silica reactions. Recycling of waste glass in concrete can divert large quantities of the market-limited (mixed-colour) waste glass from landfills for value-added use as partial replacement for cement, enable effective use of recycled aggregates in concrete, yield major cost and energy savings, and enhance the long-term performance and the sustainability of concrete-based infrastructure systems.
Structural and electrical properties of (PbSe)1·16TiSe2
Authors: Moore Daniel B. , Stolt Matthew J. , Atkins Ryan , Sitts Luke , Jones Zachary , Disch Sabrina , Beekman Matt , Johnson David C.
Published: September 2012

The synthesis and characterization of a new layered compound with the composition (PbSe)1·16TiSe2 in thin-film form is reported in this study. The structure of the new compound was characterized by specular and in-plane synchrotron x-ray diffraction studies, which indicate that the compound can be described as a layered intergrowth of PbSe and TiSe2 in which the individual constituents are precisely layered yet rotationally (turbostratically) disordered with an average in-plane domain size in the order of 10 nm. In contrast to crystalline (PbSe)1·16(TiSe2)2 prepared by solid-state reaction at high temperature, the electrical resistivity in the range 20–300 K is nearly temperature independent. The Seebeck coefficient at room temperature was measured to be S = −66(1) μV/K at the carrier concentration of n = 2·1(5) × 1021 cm−3, indicating behavior characteristic of a heavily doped semiconductor. The electrical transport properties for the (PbSe)1·16TiSe2 compound are compared and contrasted to those of other misfi t-layered and turbostratically disordered (MX)1+δ(TX2)n compounds.
Decontamination of a drinking water pipeline system contaminated with adenovirus and Escherichia coli utilizing peracetic acid and chlorine
Authors: Kauppinen Ari , Ikonen Jenni , Pursiainen Anna , Pitkänen Tarja , Miettinen Ilkka T.
Published: September 2012

A contaminated drinking water distribution network can be responsible for major outbreaks of infections. In this study, two chemical decontaminants, peracetic acid (PAA) and chlorine, were used to test how a laboratory-scale pipeline system can be cleaned after simultaneous contamination with human adenovirus 40 (AdV40) and Escherichia coli. In addition, the effect of the decontaminants on biofilms was followed as heterotrophic plate counts (HPC) and total cell counts (TCC). Real-time quantitative polymerase chain reaction (qPCR) was used to determine AdV40 and plate counting was used to enumerate E. coli. PAA and chlorine proved to be effective decontaminants since they decreased the levels of AdV40 and E. coli to below method detection limits in both water and biofilms. However, without decontamination, AdV40 remained present in the pipelines for up to 4 days. In contrast, the concentration of cultivable E. coli decreased rapidly in the control pipelines, implying that E. coli may be an inadequate indicator for the presence of viral pathogens. Biofilms responded to the decontaminants by decreased HPCs while TCC remained stable. This indicates that the mechanism of pipeline decontamination by chlorine and PAA is inactivation rather than physical removal of microbes.
Holy springs and holy water: underestimated sources of illness?
Authors: Kirschner Alexander K. T. , Atteneder Michael , Schmidhuber Angelika , Knetsch Sonja , Farnleitner Andreas H. , Sommer Regina
Published: September 2012

Use of holy springs and holy water is inherent in religious activities. Holy spring water is also used extensively for personal drinking water, although not assessed according to drinking water standards. Holy water in churches and chapels may cause infections via wetting of lips and sprinkling on persons. Our aim was to assess the microbiological and chemical water quality of holy springs and holy water in churches and hospital chapels. Of the holy springs investigated, only 14% met the microbiological and chemical requirements of national drinking water regulations. Considering results from sanitary inspections of the water catchments, no spring was assessed as a reliable drinking water source. All holy water samples from churches and hospital chapels showed extremely high concentrations of HPC; fecal indicators, Pseudomonas aeruginosa and Staphylococcus aureus occurred only in the most frequently visited churches. We conclude that it is highly necessary to include holy springs in programs for assessment and management of water quality. Public awareness has to be raised to perceive holy springs as potential sources of illness. Holy water can be another source of infection, especially in hospital chapels and frequently visited churches. Recommendations are made for proper water quality management of both water types.
Survival of human pathogenic bacteria in different types of natural mineral water
Authors: Serrano Concepción , Romero Margarita , Alou Luis , Sevillano David , Corvillo Iluminada , Armijo Francisco , Maraver Francisco
Published: September 2012

The aim of this study was to determine the survival of human pathogens (Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa) in five natural mineral waters (NMWs) with different properties and mineralization levels. Five NMWs from four Spanish spas with different dry residue at 110 °C were used: A = 76,935 mg/L; B = 1,827 mg/L; C = 808.4 mg/L; D = 283.8 mg/L; and E = 170.4 mg/L. An initial inoculum of 1 × 106 colony forming units (cfu)/mL was used for survival studies. Distilled water, chlorinated tap water and Mueller–Hinton broth were used as controls. Colony counts in all different waters were lower than those achieved with Mueller–Hinton broth over all incubation periods. A direct effect between the bacterial survival and the level of mineralization water was observed. The NMW E with low mineralization level along with the radioactive properties showed the highest antibacterial activity among all NMWs.
Investigation of water consumption patterns among Irish adults for waterborne quantitative microbial risk assessment (QMRA)
Authors: Hynds Paul D. , Misstear Bruce D. , Gill Laurence W.
Published: September 2012

Microbial and chemical contamination of drinking water supplies can cause human health problems. Microbial pathogens are of primary concern and quantitative microbial risk assessment (QMRA) is employed to assess and manage the risks they pose. Estimates of drinking water consumption, or distributions, are required to assess levels of waterborne pathogen exposure. To establish distributions for the Irish population, water consumption data were collected from 549 rural survey respondents. A further 110 participants completed a five-day water consumption diary. Average daily consumption of tap-water among the primarily rural-dwelling questionnaire respondents was 940 ml day−1 (SD 670 ml day−1) and 1,186 ml day−1 (SD 701 ml day−1) among the principally urban-dwelling diary respondents. Both mean figures are significantly less than the 2,000 ml day−1 default figure currently used for QRMA; therefore its use may lead to overestimation of the waterborne health burden. As the observed daily consumption difference between rural and urban residents is statistically significant, use of separate consumption distributions for QMRA is advocated. Although males reported higher daily tap-water consumption rates than females, these differences were insignificant, so separate consumption distributions are not considered necessary. A log-normal distribution provides the most adequate fit for daily tap-water intake (ml day−1) within both datasets.
Inactivation of Escherichia coli in water by pulsed dielectric barrier discharge in coaxial reactor
Authors: Hernández-Arias A. N. , Rodríguez-Méndez B. G. , López-Callejas R. , Alcántara-Díaz D. , Valencia-Alvarado R. , Mercado-Cabrera A. , Peña-Eguiluz R. , Muñoz-Castro A. E. , Barocio S. R. , de la Piedad-Beneitez A.
Published: September 2012

An experimental study of ATCC (American Type Culture Collection) 8739 Escherichia coli bacteria inactivation in water by means of pulsed dielectric barrier discharge (PDBD) atmospheric pressure plasmas is presented. Plasma is generated by an adjustable power source capable of supplying high voltage 25 kV pulses, ∼30 μs long and at a 500 Hz frequency. The process was conducted in a ∼152 cm3 cylindrical stainless steel coaxial reactor, endowed with a straight central electrode and a gas inlet. The bacterial concentration in water was varied from 103 up to 108E. coli cells per millilitre. The inactivation was achieved without gas flow in the order of 82% at 108 colony-forming units per millilitre (CFU mL–1) concentrations in 600 s. In addition, oxygen was added to the gas supply in order to increase the ozone content in the process, raising the inactivation percentage to the order of 90% in the same treatment time. In order to reach a higher efficiency however, oxygen injection modulation is applied, leading to inactivation percentages above 99.99%. These results are similarly valid for lower bacterial concentrations.
Municipal wastewater treatment plants as pathogen removal systems and as a contamination source of noroviruses and Enterococcus faecalis
Authors: Cheng Hui-Wen A. , Lucy Frances E. , Broaders Michael A. , Mastitsky Sergey E. , Chen Chien-Hsien , Murray Amanda
Published: September 2012

Municipal wastewater treatment plants play a crucial role in reducing the microbial and pathogen load of human wastes before the end-products are discharged to surface waters (final effluent) or land spread (biosolids). This study investigated the occurrence frequency of noroviruses, Enterococcus faecalis and Enterococcus faecium in influent, final effluent and biosolids from four secondary wastewater treatment plants in northwestern Ireland (plants A–D) and observed the seasonal and spatial variation of the plant treatment efficiencies in the pathogen removals. It was noted that norovirus genogroup II was more resistant to the treatment processes than the norovirus genogroup I and other active viral particles, especially those in the discharge effluents. The percolating biofilm system at plant D resulted in better effluent quality than in the extended aerated activated sludge systems (plants A and B); primary biosolids produced at plant D may pose a higher health risk to the locals. The spread of norovirus genogroup II into the environment, irrespective of the wastewater treatment process, coincides with its national clinical predominance over norovirus genogroup I. This study provides important evidence that municipal wastewater treatment plants not only achieve pathogen removal but can also be the source of environmental pathogen contamination.
Estimation of pathogen concentrations in a drinking water source using hydrodynamic modelling and microbial source tracking
Authors: Sokolova Ekaterina , Åström Johan , Pettersson Thomas J. R. , Bergstedt Olof , Hermansson Malte
Published: September 2012

The faecal contamination of drinking water sources can lead to waterborne disease outbreaks. To estimate a potential risk for waterborne infections caused by faecal contamination of drinking water sources, knowledge of the pathogen concentrations in raw water is required. We suggest a novel approach to estimate pathogen concentrations in a drinking water source by using microbial source tracking data and fate and transport modelling. First, the pathogen (norovirus, Cryptosporidium, Escherichia coli O157/H7) concentrations in faecal contamination sources around the drinking water source Lake Rådasjön in Sweden were estimated for endemic and epidemic conditions using measured concentrations of faecal indicators (E. coli and Bacteroidales genetic markers). Afterwards, the fate and transport of pathogens within the lake were simulated using a three-dimensional coupled hydrodynamic and microbiological model. This approach provided information on the contribution from different contamination sources to the pathogen concentrations at the water intake of a drinking water treatment plant. This approach addresses the limitations of monitoring and provides data for quantitative microbial risk assessment (QMRA) and risk management in the context of faecal contamination of surface drinking water sources.
Outcomes of Male Patients with Alport Syndrome Undergoing Renal Replacement Therapy
Authors: Temme Johanna , Kramer Anneke , Jager Kitty J. , Lange Katharina , Peters Frederick , Müller Gerhard-Anton , Kramar Reinhard , Heaf James G. , Finne Patrik , Palsson Runolfur , Reisæter Anna V. , Hoitsma Andries J. , Metcalfe Wendy , Postorino Maurizio , Zurriaga Oscar , Santos Julio P. , Ravani Pietro , Jarraya Faical , Verrina Enrico , Dekker Friedo W. , Gross Oliver
Published: September 2012

Background and objectives

Patients with the hereditary disease Alport syndrome commonly require renal replacement therapy (RRT) in the second or third decade of life. This study compared age at onset of RRT, renal allograft, and patient survival in men with Alport syndrome receiving various forms of RRT (peritoneal dialysis, hemodialysis, or transplantation) with those of men with other renal diseases.

Design, setting, participants, & measurements

Patients with Alport syndrome receiving RRT identified from 14 registries in Europe were matched to patients with other renal diseases. A linear spline model was used to detect changes in the age at start of RRT over time. Kaplan-Meier method and Cox regression analysis were used to examine patient and graft survival.

Results

Age at start of RRT among patients with Alport syndrome remained stable during the 1990s but increased by 6 years between 2000–2004 and 2005–2009. Survival of patients with Alport syndrome requiring dialysis or transplantation did not change between 1990 and 2009. However, patients with Alport syndrome had better renal graft and patient survival than matched controls. Numbers of living-donor transplantations were lower in patients with Alport syndrome than in matched controls.

Conclusions

These data suggest that kidney failure in patients with Alport syndrome is now being delayed compared with previous decades. These patients appear to have superior patient survival while undergoing dialysis and superior patient and graft survival after deceased-donor kidney transplantation compared with patients receiving RRT because of other causes of kidney failure.
Association of Modality with Mortality among Canadian Aboriginals
Authors: Sood Manish M. , Hemmelgarn Brenda , Rigatto Claudio , Komenda Paul , Yeates Karen , Promislow Steven , Mojica Julie , Tangri Navdeep
Published: September 2012

Background and objectives

Previous studies have shown that Aboriginals and Caucasians experience similar outcome on dialysis in Canada. Using the Canadian Organ Replacement Registry, this study examined whether dialysis modality (peritoneal or hemodialysis) impacted mortality in Aboriginal patients.

Design, setting, participants, & measurements

This study identified 31,576 adult patients (hemodialysis: Aboriginal=1839, Caucasian=21,430; peritoneal dialysis: Aboriginal=554, Caucasian=6769) who initiated dialysis between January of 2000 and December of 2009. Aboriginal status was identified by self-report. Dialysis modality was determined 90 days after dialysis initiation. Multivariate Cox proportional hazards and competing risk models were constructed to determine the association between race and mortality by dialysis modality.

Results

During the study period, 939 (51.1%) Aboriginals and 12,798 (53.3%) Caucasians initiating hemodialysis died, whereas 166 (30.0%) and 2037 (30.1%), respectively, initiating peritoneal dialysis died. Compared with Caucasians, Aboriginals on hemodialysis had a comparable risk of mortality (adjusted hazards ratio=1.04, 95% confidence interval=0.96–1.11, P=0.37). However, on peritoneal dialysis, Aboriginals experienced a higher risk of mortality (adjusted hazards ratio=1.36, 95% confidence interval=1.13–1.62, P=0.001) and technique failure (adjusted hazards ratio=1.29, 95% confidence interval=1.03–1.60, P=0.03) than Caucasians. The risk of technique failure varied by patient age, with younger Aboriginals (<50 years old) more likely to develop technique failure than Caucasians (adjusted hazards ratio=1.76, 95% confidence interval=1.23–2.52, P=0.002).

Conclusions

Aboriginals on peritoneal dialysis experience higher mortality and technique failure relative to Caucasians. Reasons for this race disparity in peritoneal dialysis outcomes are unclear.
Packed bed column studies for the removal of dyes using novel sorbent
Authors: Rajeshkannan R. , Rajasimman M. , Rajamohan N.
Published: September 2012

A continuous fixed bed study was carried out by using tamarind seed as a
sorbent for the removal of malachite green (MG) and acid blue 9(AB9) from
aqueous solution. The effect of factors, such as flow rate and bed depth was
studied. Data confirmed that the breakthrough curves were dependent on flow
rate and bed depth. Thomas, Adams-Bohart, and Yoon-Nelson models were applied
to experimental data to predict the breakthrough curves using non-linear
regression and to determine the characteristic parameters of the packed bed
column. Bed depth/service time analysis (BDST) model was used to express the
effect of bed depth on breakthrough curves. The results showed that Thomas
model was found suitable for the normal description of breakthrough curve at
the experimental condition, while Adams-Bohart and Yoon-Nelson model were
able to explain only the initial part of dynamic behaviour of the tamarind
seed column. The data were in good agreement with BDST model. It was
concluded that the tamarind seed can be effectively used as a sorbent for the
removal of dyes.
Local capacitance analysis using a modified deep level spectrometer
Authors: Dózsa László , Lányi Štefan
Published: September 2012

A bimorph-based xz scanner and an amplifier, increasing the capacitance and current measurement sensitivities 250-times and 1000-times, respectively, have been built into the cryostat of a deep level transient spectrometer. The setup renders point by point local capacitance-voltage (C–V) at 1 MHz and dc currentvoltage (I–V) measurements using a sharp tip placed into tunnelling distance from the surface of analysed semiconductor sample. The C–V measurements revealed a strong dependence on the probe/sample separation, ranging from MOS-type at small tunnelling currents to Schottky-type at currents exceeding approximately 10 pA. Marked hysteresis was observed, indicating changes of surface state occupancy. These slow states are otherwise hardly detected, since they are absent in semiconductor/metal contacts and in MOS structures they would become mostly passivated interface states. The setup enables calibrated, fixed zero level capacitance measurement. The stray capacitance is the dominant component of the measured capacitance but it can be easily discarded.
Anxiety and social activities in multiple sclerosis patients
Authors: Leonavičius Rytis , Adomaitienė Virginija
Published: September 2012

Despite that the prevalence of depression has been thoroughly analyzed in multiple sclerosis (MS) patients and affects approximately 15%–20% of the MS population, attention paid to social activities concomitant with anxiety is still too sporadic. The aim of this study was to find the prevalence of anxiety and social activities aggraded/aggravated with anxiety in the MS population in Lithuania and to analyze how it correlates with socio-demographic factors, clinical outcomes of MS and depression. Three hundred twelve MS patients took part in this study; anxiety prevalence was pointed in 20.2%. Only 23.4% of the study population was socially active. Our study shows a significant level of anxiety and low level of social activity in people with MS. Anxiety in MS patients was strongly related with younger age, shorter MS duration, prevalence of depression and lower level of social activity. A higher level of social activity was significantly related with older urban MS patients who indicated family status as living together and longer MS duration.
The basis of the discovery process for a new pharmaceutical product
Authors: Dickov Veselin
Published: September 2012

The basis of the discovery process for a new pharmaceutical product is in understanding the mechanism of action of a particular disease or processes in the organism related to the disease and/or its symptoms. The essence of a pharmaceutical is in the active ingredient capable of affecting processes within the organism beneficially. The discovery process includes a particular sequence of activities of various profiles of experts, about which various authors agree. The history of pharmaceutical industry (and pharmacy) is measured from one discovery of an innovative drug or approach to treatment of a particular disease to the next one. The cost of pharmaceutical products is one of the key causes of controversy related to this industry. Numerous cultures have proverbs expressing the opinion that health is priceless or that health is the greatest wealth. What if health does have a price? One of the basic premises of marketing is that price should reflect consumer value.
The strongest resistance of Staphylococcus aureus to erythromycin is caused by decreasing uptake of the antibiotic into the cells
Authors: Piątkowska Elżbieta , Piątkowski Jerzy , Przondo-Mordarska Anna
Published: September 2012

The consequence of excessive use of macrolides is a high occurrence of mechanisms responsible for resistance to these drugs. Of 97 erythromycin-resistant bacterial strains gathered in the Wrocław area in Poland, 60% exhibited very high resistance, and those with the inducible MLSB (macrolide-lincosamide-streptogramin B) resistance phenotype predominated. Direct genetic investigation revealed that the erm genes coding for ribosomal methylases are the most frequently occurring erythromycin resistance-determining genes. No genetic resistance determinant was detected in 13% of the erythromycin-resistant strains. The efflux mechanism occurs in strains isolated from the nasopharyngeal cavity twice as often as in those isolated from other material, where the mechanism connected with target site modification predominates. Measurements of radiolabelled antibiotic accumulation inside bacterial cells revealed that in highly resistant strains (MIC > 1024 μg/ml), an important factor responsible for the resistance is the permeability barrier at the cell wall level. This would be a hitherto unknown mechanism of resistance to erythromycin in Staphylococcus aureus.
Body posture of young female basketball players
Authors: Grabara Małgorzata
Published: September 2012

Body posture of young female basketball players

Study aim: To assess body posture and somatic parameters in young females practicing basketball in comparison with their non-training peers and to state whether there is a relationship between the quality of one's posture and the length and frequency of training.

Material and methods: The study included 32 young female basketball players aged 13-15 years old. The period of basketball practice was 3-4 years for the group aged 13-14 years; the frequency of practice was 3-7 times per week. In the case of the group of 15-year-olds, it was 4-5 years, 4-7 times a week, respectively. The control group consisted of 37 young female subjects in the same age brackets that did not participate in any directed physical activity. Body height was measured with the use of a height meter at medical scales, whereas body mass, fat mass, and total body water mass were defined with the use of Tanita electronic scale. A specialist device using the projection Moiré method (MORA, CQElektronik System, Poland) was used to assess one's body posture.

Results: Body height and water mass were significantly different in the younger group. However, the parameters of body posture differed significantly only in the group of 15-year-olds. The following have been observed: much greater asymmetries in pelvic placement in the transverse plane (p<0.05), significantly greater asymmetries of shoulder blades in relation to the transverse plane (p<0.01), as well as significantly smaller thoracic kyphosis angle (p<0.05) in female basketball players in comparison with the placement of the above parameters in their non-training peers. Moreover, correlations between the frequency of basketball practice and the deflection of the line of spinous processes, torso inclination angle, placement of shoulder blades in the transverse plane and towards the spine, kyphosis angle, and a synthetic index of body posture (i.e. postural symmetry) were noted.

Conclusions: Training basketball may lead to increased occurrence of asymmetry of one's body posture.
An application of New Keynesian models to inflation in Croatia
Authors: Domić Alan
Published: September 2012

An application of New Keynesian models to inflation in Croatia

Background: The inflation dynamics of Croatia is studied in the paper, with the review of applicable marginal cost proxies for the hybrid New Keynesian Phillips Curve (NKPC), and estimation of three specifications of the hybrid NKPC for Croatia. Objectives: The goal of this research is to examine the effect of labor's share of income, the price of energy, and the price of imports and other open economy factors in driving inflation in Croatia from the first quarter of 2000 to the fourth quarter of 2011. Methods/Approach: We use the generalized method of moments (GMM) estimator to empirically estimate three NKPC specifications. The J-stat and Cragg-Donald F-test are used to test for overidentification and for weak instruments, respectively. Results: We find that the marginal cost proxy for the energy-augmented specification is statistically significant and quantitatively the largest, whereas those for the other two are statistically significant, but quantitatively negligible. Conclusions: The results provide an empirical contribution both to the literature on inflation in Croatia and the literature of the NKPC in a small open economy. We can conclude that the price of energy has been the strongest driver of inflation, whereas the open economy factors we tested have had very little influence.
Decision making based on single and double acceptance sampling plans for assessing quality of lots
Authors: Dumičić Ksenija , Žmuk Berislav
Published: September 2012

Decision making based on single and double acceptance sampling plans for assessing quality of lots

Background: Acceptance sampling is a statistical tool of quality control. Sampling plans and operating characteristic (OC) curves are very useful for conducting acceptance sampling and provide the quality manager with tools to evaluate the quality of a production run or shipment. There are developed different sampling plans, but common used in practise are single and double acceptance sampling plans. Objectives: The goal of the paper is to test if applying of single and double sampling plan can lead to statistically significant different conclusion about quality level of observed lot. Methods/Approach: Statistical tests of difference in proportions are used to test if there is some statistically significant difference in probabilities of lot fraction defectives between a single and a double sampling plan at the same levels of probability of acceptance. Results: The results of the analysis show that in some cases there is statistically significant difference. Namely, the quality manager should be careful when he chooses to use, instead of the first, the second sampling plan with different parameters because on that way he could make statistically significant different conclusion about quality level of observed lot. Conclusions: The paper shows that some intentional manipulations by using different sampling plans are possible.
Criteria weighting by using the 5Ws & H technique
Authors: Čančer Vesna
Published: September 2012

Criteria weighting by using the 5Ws & H technique

Background: This paper introduces the use of the 5Ws & H technique, which is the creative problem solving technique based on who, what, when, where, why and how questions, for the establishing of the criteria weights in multi-criteria decision-making (MCDM). Objectives: The main goal of this paper is to adapt and complete the steps of the 5Ws & H technique, usually used in the problem definition phase, to establish the importance of criteria by the methods based on an interval scale. It also aims to verify the applicability of the proposed approach in the selection of the most appropriate blade. Methods/Approach: In terms of prescriptive approach, the creative 5Ws & H technique was used in the weighting step of the frame procedure for MCDM. During synthesis, the additive model was used, whereas interactions among criteria were considered by using the discrete Choquet integral. Results: The first result is a theoretical statement of the weighting scheme for a new decision mechanism. The second result is the application of this scheme in a real-world case-study. Considering interactions among criteria strengthened the decision-making basis in the selection of the most appropriate blade. Conclusion: The creative 5Ws & H technique proved useful in criteria weighting.
Principal component analysis for authorship attribution
Authors: Jamak Amir , Savatić Alen , Can Mehmet
Published: September 2012

Principal component analysis for authorship attribution

Background: To recognize the authors of the texts by the use of statistical tools, one first needs to decide about the features to be used as author characteristics, and then extract these features from texts. The features extracted from texts are mostly the counts of so called function words. Objectives: The data extracted are processed further to compress as a data with less number of features, such a way that the compressed data still has the power of effective discriminators. In this case feature space has less dimensionality then the text itself. Methods/Approach: In this paper, the data collected by counting words and characters in around a thousand paragraphs of each sample book, underwent a principal component analysis performed using neural networks. Once the analysis was complete, the first of the principal components is used to distinguish the books authored by a certain author. Results: The achieved results show that every author leaves a unique signature in written text that can be discovered by analyzing counts of short words per paragraph. Conclusions: In this article we have demonstrated that based on analyzing counts of short words per paragraph authorship could be traced using principal component analysis. Methodology could be used for other purposes, like fraud detection in auditing.
An experimental comparison of some heuristics for cardinality constrained bin packing problem
Authors: Remic Maja , Žerovnik Gašper , Žerovnik Janez
Published: September 2012

An experimental comparison of some heuristics for cardinality constrained bin packing problem

Background: Bin packing is an NPhard optimization problem of packing items of given sizes into minimum number of capacitylimited bins. Besides the basic problem, numerous other variants of bin packing exist. The cardinality constrained bin packing adds an additional constraint that the number of items in a bin must not exceed a given limit Nmax. Objectives: Goal of the paper is to present a preliminary experimental study which demostrates adaptations of the new algorithms to the general cardinality constrained bin packing problem. Methods/Approach: Straightforward modifications of First Fit Decreasing (FFD), Refined First Fit (RFF) and the algorithm by Zhang et al. for the bin packing problem are compared to four cardinality constrained bin packing problem specific algorithms on random lists of items with 0%, 10%, 30% and 50% of large items. The behaviour of all algorithms when cardinality constraint Nmax increases is also studied. Results: Results show that all specific algorithms outperform the general algorithms on lists with low percentage of big items. Conclusions: One of the specific algorithms performs better or equally well even on lists with high percentage of big items and is therefore of significant interest. The behaviour when Nmax increases shows that specific algorithms can be used for solving the general bin packing problem as well.
Change Management as a Critical Success Factor in e-Government Implementation
Authors: Nograšek Janja
Published: September 2012

Change Management as a Critical Success Factor in e-Government Implementation

Change management in e-government implementation is a very complex issue. E-government services are frequently distributed over different IT systems and organizations. There are also events from outside the public administration that cause changes such as government policies and legislation, public-private partnership, etc., and finally a huge resistance to change exists in public administration proverbial. Another problem is that the e-government is predominantly seen only as a technology mission and not as an organizational transformation issue. Those are probably the main reasons that the existing literature about change management in e-government is still missing at large. There are articles dealing with some aspects of changes affected by the new technology implementation, however, there is no comprehensive framework that would identify changes that have to be managed in e-government implementation. Therefore, the main aim of the paper is to identify a comprehensive set of changes that have to be considered in e-government implementation and the role of leadership in such processes. Finally, the paper proposes a conceptual model of change management in e-government implementation.
Invited article: Adaptability
Authors: Rud Olivia
Published: September 2012

Invited article: Adaptability

For the last several decades, organizations have dealt with economic shifts using change management. Based on the new science, there are two major flaws with this approach. First, the word change implies an event with an ending. Second, it implies that change can be managed. In a world of economic volatility, this approach is no longer viable. The continuous climate of uncertainty and volatility demands another view, one that supports adaptability and resilience.
Social Network Mixing Patterns In Mergers & Acquisitions - A Simulation Experiment
Authors: Fabac Robert , Schatten Markus , Đuričin Tomislav
Published: September 2012

Social Network Mixing Patterns In Mergers & Acquisitions - A Simulation Experiment

In the contemporary world of global business and continuously growing competition, organizations tend to use mergers and acquisitions to enforce their position on the market. The future organization's design is a critical success factor in such undertakings. The field of social network analysis can enhance our uderstanding of these processes as it lets us reason about the development of networks, regardless of their origin. The analysis of mixing patterns is particularly useful as it provides an insight into how nodes in a network connect with each other. We hypothesize that organizational networks with compatible mixing patterns will be integrated more successfully. After conducting a simulation experiment, we suggest an integration model based on the analysis of network assortativity. The model can be a guideline for organizational integration, such as occurs in mergers and acquisitions.
Renewable Resources, Capital Accumulation, and Economic Growth
Authors: Zhang Wei-Bin
Published: September 2012

Renewable Resources, Capital Accumulation, and Economic Growth

This paper proposes a dynamic economic model with physical capital and renewable resources. Different from most of the neoclassical growth models with renewable resources which are based on microeconomic foundation and neglect physical capital accumulation, this study proposes a growth model with dynamics of renewable resources and physical capital accumulation. The model is a synthesis of the neoclassical growth theory and the traditional dynamic models of renewable resources with an alternative approach to household behavior. The model describes a dynamic interdependence among physical accumulation, resource change, and division of labor under perfect competition. Because of its refined economic structure, our study enables some interactions among economic variables which are not found in the existing literature on economic growth with renewable resources. We simulate the model to demonstrate the existence of equilibrium points and motion of the dynamic system. Our comparative dynamic analysis shows, for instance, that a rise in the propensity to consume the renewable resource increases the interest rate and reduces the national and production sector's capital stocks, wage rate and level of the consumption good. Moreover, it initially reduces and then increases the capital stocks of the resource sector and the consumption and price of the renewable resource. The stock of the renewable resource is initially increased and then reduced. Finally, labor is redistributed from the production to the resource sector.
Business Trends and Tendencies in Organization Design and Work Design Practice: Identifying Cause-and-Effect Relationships
Authors: Hernaus Tomislav
Published: September 2012

Business Trends and Tendencies in Organization Design and Work Design Practice: Identifying Cause-and-Effect Relationships

Current global business environment has a strong impact on theory and practice of organizations, as well as on working behavior of their employees. Increased complexity and competitiveness is changing settled ways of organizing and working. The ultimate search for the holy grail of achieving organizational effectiveness through better design solutions is gaining momentum. There are many possible areas and means for improvement. Great opportunities emerge from better understanding of contemporary organization and work environment. To seize them, the link between organization design and work design tendencies will be emphasized. Through an in-depth theoretical research on current business trends and their impact on the changing nature of work in organizations, potentially very strong patterns between these two different environmental categories and levels of analysis will be identified. Our extensive analysis of current trends and tendencies in organization design and work design field will provide useful insights for business practitioners and researchers.
Do macroeconomic factors matter for stock returns? Evidence from estimating a multifactor model on the Croatian market
Authors: Benaković Dubravka , Posedel Petra
Published: September 2012

Do macroeconomic factors matter for stock returns? Evidence from estimating a multifactor model on the Croatian market

Factor models observe the sensitivity of an asset return as a function of one or more factors. This paper analyzes returns on fourteen stocks of the Croatian capital market in the period from January 2004 to October 2009 using inflation, industrial production, interest rates, market index and oil prices as factors. Both the direction and strength of the relation between the change in factors and returns are investigated. The analyses included fourteen stocks and their sensitivities to factors were estimated. The results show that the market index has the largest statistical significance for all stocks and a positive relation to returns. Interest rates, oil prices and industrial production also marked a positive relation to returns, while inflation had a negative influence. Furthermore, cross-sectional regression with the estimated sensitivities used as independent variables and returns in each month as dependent variables is performed. This analysis resulted in time series of risk premiums for each factor. The most important factor affecting stock prices proved to be the market index, which had a positive risk premium. A statistically significant factor in 2004 and 2008 was also inflation, marking a negative risk premium in 2004 and a positive one in 2008. The remaining three factors have not shown as significant.
Reaching inter-institutional business processes in e-Society
Authors: Vlahović Nikola
Published: September 2012

Reaching inter-institutional business processes in e-Society

Each business enterprise strives to achieve the most efficient organization of its operations. While business enterprises can influence internal factors of organization, external factors are more rigid. Public organizations have less of an incentive to be efficient. Furthermore, their organization is less favorable since the decision making is centralized and highly formal (i.e. legislative). Adoption of business process orientation (BPO) paradigm, with an emphasis on the management of internal factors of organization, has provided business organizations with substantial savings and improvements in efficiency. However, external factors also have a high potential for improvement of efficiency. For instance, development of supply chains or value chains has proven that external factors can be harnessed to provide additional sources of competitiveness. Other external factors can also be used to improve the performance of individual organizations, an entire industry or economy as a whole. These synergic effects can be achieved through a unified and virtualized communication infrastructure, document exchange and conduct of business transactions. The goal of this paper is to present business environment properties in an e-Society that can be further developed to enhance integration between organizations and public institutions, which in turn can be used to create and manage inter-institutional business processes. This type of processes can promote e-business and e-business models to a new level of efficiency, making a whole industry or national economy comparatively more competitive in international markets.
Correlation of Intra-Articular Ankle Pathology with Cytokine Biomarkers and Matrix Degradation Products
Authors: Giovanni Thomas P. San , Golish S. Raymond , Palanca Ariel , Hanna Lewis S. , Scuderi Gaetano J.
Published: September 2012

Background: Articular cartilage degeneration is mediated by inflammatory cytokines and fragments of structural matrix proteins. Few studies have examined the role of these biomarkers in intra-articular pathology of the ankle. Methods: Four groups of patients with increasing ankle pathology were enrolled. Group 1 included controls with no pain who underwent unrelated forefoot surgery. Group 2 included patients undergoing arthroscopy with intraoperative mild chondrosis. Group 3 included patients undergoing arthroscopy with moderate/severe chondrosis, osteochondral lesions, impingement, or loose bodies. Group 4 included positive controls with severe arthrosis undergoing ankle arthrodesis/arthroplasty. Ankle fluid was obtained by intra-articular aspiration and was assayed for IL-6, IFN-γ, MCP, MIP-1β, and fibronectin-aggrecan complex (FAC), a matrix-degradation marker. There were 36 patients total, 21 males and 15 females with a mean age 45 (±16; range 18 to 76) years and a mean VAS for pain of 4.7 (±3.5; range 0 to 9). In groups 1 through 4, there were 11, 6, 15 and 4 patients respectively. Results: The mean values of MCP-1 were 49.8 (±8.0) for minimal pathology and 133.9 (±33.0) for substantial pathology (pg/ml). The mean values of the FAC were 2.83 (±1.16) for minimal pathology and 9.62 (±2.23) for substantial pathology (optical density at 450 nm). The groups differed significantly in age, preoperative VAS, FAC, IL-6, and MCP-1 ( p < 0.05). Conclusion: There are differences in FAC and MCP-1 with increasing grades of severity of intra-articular pathology. Clinical Relevance: These tests may play a role in determining the necessity for arthroscopy or intra-articular procedures in equivocal candidates.

Level of Evidence: II