bluuebunny/crossref_metadata_2025 huggingface dataset:
Raman Hyperspectral Imaging Spectrometer Utilizing Crystalline Colloidal Array Photonic Crystal Diffraction
Authors: Hufziger Kyle T. , Bykov Sergei V. , Asher Sanford A.
Published: October 2014

We fabricated a novel hyperspectral Raman imaging spectrometer that, for the first time, uses a photonic-crystal wavelength-selecting device to select a narrow-wavelength spectral interval. The photonic crystal consists of an array of highly charged, monodisperse polystyrene particles that self-assemble into a face-centered cubic crystal. The photonic crystal Bragg-diffracts a narrow spectral interval that can be tuned by altering the incident angle of collimated Raman scattered light. Our prototype spectrometer diffracts a ∼200 cm−1 interval of the 488 nm excited visible Raman spectrum of Teflon. This enabled us to select a close-lying triplet of Teflon Raman bands. We imaged the Teflon surface by focusing this narrow region onto a charge-coupled device to create a Raman image of the sample surface that spectrally details the chemical composition.
Locus of control, academic self-concept, and academic dishonesty among high ability college students
Authors: Rinn Anne , Boazman Janette , Jackson Ann , Barrio Brenda
Published: October 2014

The purposes of the current study were to evaluate a measure of academic dishonesty and examine high ability college students’ loci of control and its effect on behaviors of academic dishonesty, as moderated by academic self-concept. A total of 357 high ability college students enrolled at two universities in the southwestern United States took part in this study. Variables and the moderation of academic self-concept were examined for the aggregate group (n = 357) and for the disaggregate honors and non-honors groups. Students completed the Rotter Internal-External Locus of Control Scale (Rotter, 1966), the Self-Description Questionnaire III (Marsh, 1989), and a scale to measure academic dishonesty based on the work of Geddes (2011). A 17-item measure of academic dishonesty was developed. Results indicate locus of control does not significantly predict academic dishonesty for the non-honors group, but several relationships were found among variables for the aggregate group and for the honors and non-honors groups.
The effects of implementing recitation activities on success rates in a college calculus course
Authors: Watt Jeffrey Xavier , Feldhaus Charles R. , Sorge Brandon H. , Fore Grant A. , Gavrin Andrew D. , Marrs Kathleen A.
Published: October 2014

Over a period of six years, three different types of recitation sessions were implemented into the large enrollment section of a college calculus course. During the fall semesters, the results on the departmental final examination, the DFW rates, and the one-year retention rates of students as STEM majors were examined by the type of recitation session used with the large enrollment section. The three types of recitation sessions studied were: (1) optional mentoring sessions at the Math Assistance Center conducted by undergraduate students (peer mentors), (2) required mentoring sessions conducted by graduate students, and (3) required VGNA (Verbal, Graphical or Geometric, Numeric, and Algebraic) Concept activities, which were also coupled with mentoring sessions conducted by graduate students. The success of the students in the large enrollment section of the course, which included one of the three different types of recitation sessions, was compared to the success of students in the small enrollment sections of the course (enrollments less than 50 students). The effects of using each type of recitation session on raising departmental final examination scores, lowering DFW rates, and raising one-year retention rates is presented. The results of this study demonstrate methods of raising student success rates in large enrollment (lecture-format) courses.
“Who am I to bring diversity into the classroom?” Learning communities wrestle with creating inclusive college classrooms
Authors: Considine Jennifer R , Mihalick Jennifer E , Mogi-Hein Yoko R , Penick-Parks Marguerite W , Van Auken Paul M
Published: October 2014

This study explored the experiences of gateway course instructors during the implementation of pedagogical changes aimed at improving the success of diverse students. A detailed case study was built through analysis of peer observations, focus groups, oral and written reflections, student grades, in-depth interviews, and pre and post student surveys. Results showed that instructors faced three major challenges in implementing pedagogical changes: pragmatic challenges, student-centered challenges, and challenges to instructor self-concept. Embracing a learning paradigm and participating in a learning community helped instructors to manage these challenges and create more inclusive learning environments for students.
The Timing of Codevelopment Alliances in New Product Development Processes: Returns for Upstream and Downstream Partners
Authors: Fang Eric (Er) , Lee Jongkuk , Yang Zhi
Published: October 2014

Upstream biotech firms (i.e., upstream partners) and downstream pharmaceutical firms (i.e., downstream partners) often form alliances to cope with performance uncertainty and to exploit product specificity in new product development. Although the performance implications of such alliances have been investigated, research has not offered insight into how the timing of such codevelopment alliances influences partner returns. The authors develop and test predictions that timing changes the costs and benefits accruing to upstream and downstream partners and that the effect of timing is influenced by a set of alliance, firm, and market conditions. An event study of 276 codevelopment agreements between biotech and pharmaceutical firms during 1998–2010 reveals that alliance governance structure, partner technological capability, and the competitiveness of market environments change the abnormal returns achieved by partners entering these relationships in important ways.
Jie Huang: Interregional Recognition and Enforcement of Civil and Commercial Judgments
Authors: Cheng Tan Lee
Published: October 2014

Review of “Interregional Recognition and Enforcement of Civil and Commercial Judgments” by Professor Jie Huang (Oxford and Portland, Oregon: Hart Publishing, 2014) which analyses the status quo of judgment recognition and enforcement in the Mainland China, Macao and Hong Kong under the ‘One Country, Two Systems’ regime. The book also presents a comparative study of the interregional recognition and enforcement of judgments in the US and EU.
Properties of polyurethane (PUR) films prepared from liquefied wood (LW) and ethylene glycol (EG)
Authors: Lee Wen-Jau , Kuo En-Shao , Chao Chung-Yu , Kao Yu-Pin
Published: October 2014

The wood of Cryptomeria japonica D. Don was liquefied in ethylene glycol (EG) with sulfuric acid (H2SO4) as a catalyst at 150°C for 60 min. The liquefied wood (LW)- and EG-based polyester polyols (EG-Polyest.-ol) were synthesized by reacting LW and EG with adipic acid (AA), respectively. Polyurethane (PUR) resins were made by mixing Polyest.-ol with isocyanate. The results show that LW-Polyest.-ol is a suitable raw material for PUR. The PUR films prepared with LW-Polyest.-ol have higher tensile strength with less elongation at breaking point than that with EG-Polyest.-ol. According to dynamic thermomechanical analysis, the PUR films prepared with EG-Polyest.-ol have a homogeneous molecular structure, whereas a phase separation has been found for those made with LW-Polyest.-ol. Thermal gravimetric analysis showed that the thermal degradation of LW-PUR films only starts at higher temperature than that of EG-PUR.
Young’s modulus and shear modulus of solid wood measured by the flexural vibration test of specimens with large height/length ratios
Authors: Yoshihara Hiroshi , Yoshinobu Masahiro
Published: October 2014

The Young’s modulus (modulus of elasticity, MOE) in the longitudinal (L) and radial (R) directions and the shear modulus (SM) in the LR plane of Douglas fir were determined by the flexural vibration (FV) tests under the free-free condition based on Timoshenko’s vibration equation. In the tests, the height/length (H/L) ratio was varied from 0.05 to 0.3. In addition, the test data were analyzed numerically and the effectiveness of Timoshenko’s equation was examined. The MOE and SM were calculated based on the rigorous and approximated solutions of Timoshenko’s equation. The inaccuracy of the approximated solution was enhanced when the H/L ratio of the specimen was too large. In contrast, the rigorous solution enabled the accurate calculation of these moduli in a wider range of length/depth ratios than the approximated solution.
A preliminary comparison of primary care use by refugees before and after acupuncture
Authors: Highfield Ellen Silver , Longacre Mckenna , Sager Alan , Grodin Michael A.
Published: October 2014

Background: Limited research exits on utilization and cost-effectiveness of acupuncture among underserved communities, and virtually no evidence has been published with respect to refugee populations. In this study, we examined the relationship between acupuncture and the total utilization of primary care services in a cohort of refugee patients with chronic pain.

Methods: We retrospectively reviewed the medical records of 16 refugee patients with chronic pain at Boston Medical Center (BMC). The research was IRB-approved. Demographics and total charges associated with primary care over 18 months were collected.

Results: Total charges associated with primary care services decreased by 50.2% in our refugee cohort in the 12 months following acupuncture treatment, equivalent to a savings of $691 per patient per month.

Conclusions: This preliminary review demonstrated a statistically significant decrease in total charges associated with primary care following acupuncture treatment (p=0.0308). This study suggests the need for further investigation of the relation between acupuncture and refugees with chronic pain, as well as the financial implications of this relationship. It is unclear why refugees may seek fewer primary care services after acupuncture treatment. Additional study is needed to further explore whether this relationship is generalizable to other hospital services and to other patient populations.
Novel Force Modelling Technique for Grinding
Authors: Vinay P.V. , Rao Ch. Srinivasa , Rao I.H. Nagaraja
Published: October 2014

Grinding occupies a place in the machining arena as the final finishing process, which tends to exist in all machining environments. The grinding process generates forces that have to be countered by the robustness of the machine tool and a methodology to compute the forces that might be generated by it for deciding the type of tool and depth of cut to be used for a given variety of workpiece. Prior computation of the forces being the primary concern can be a handful of help to the industrial personnel and managements to decide on the variety of machine tool and accessories to be bought for the kind of grinding to be done. Comparison of the proposed model with the available literature shows good agreement.
Multi-Response Optimization in Drilling of Composites: Introduction of a Similarity Based Approach in Combination with Taguchi's Philosophy
Authors: Abhishek Kumar , Datta Saurav , Mahapatra Siba Sankar
Published: October 2014

In recent years, the application of polymer composites has been enormously increased particularly in aerospace as well as in automobile sector due to its light weight, high specific stiffness and high specific strength. Machining of those composites has really become an emerging area of research. A considerable volume of research has already been carried out by the pioneers in order to study machining and machinability aspects of these composites, thereby, maintaining both product quality as well as productivity. Drilling is considered as one of the most common machining processes for assembly of composites. In case of fiber reinforced polymer (FRP) composites, delamination and fiber pull out are the major problems that arise during drilling operations. Defect free drilling whilst ensuring satisfactory machining performance (in terms of quality as well as productivity) is definitely a challenging task. In this context, the present study mainly attempts to reduce drilling induced damages and at the same time to improve machining performances during drilling of polymer composites by determining an optimal parametric combination in view of multiple process responses and by considering effects of drilling process control parameters, drill geometry (diameter of drill bit) as well as composite type. Attempt has also been made to understand the relationship (influence) between input-output(s); where, inputs i.e. process parameters have been considered like composite type, drill speed, feed rate, drill diameter and outputs have been and drilling responses like thrust force, torque, delamination at entry and exit and average surface roughness of the drilled hole. Multi-response optimization has been performed using Deng's similarity based method in combination with Taguchi's optimization philosophy. Results obtained thereof have been compared with TOPSIS (Technique for Order Preference by Similarity to Ideal Solution)-based Taguchi approach.
Hybrid Monte Carlo methods in credit risk management
Authors: Del Chicca Lucia , Larcher Gerhard
Published: October 2014

In this paper we analyze and compare the use of Monte Carlo, quasi-Monte Carlo and hybrid Monte Carlo methods in the credit risk management system “Credit Metrics” by J. P. Morgan. We show that hybrid sequences, used suitably for simulations, perform better, in many relevant situations, than pure Monte Carlo and pure quasi-Monte Carlo methods, and they only rarely perform worse than these methods.
Fiber loading and treatment effects on dry sliding wear of Palmyra fruit fiber composites
Authors: Sankar Irullappasamy , Ravindran Durairaj
Published: October 2014

This study focused on the dry sliding wear behavior of the natural fiber called borassus fruit fiber (Palmyra fruit fiber) reinforced polyester composite. Composites are molded with different fiber weight fractions. Composites are fabricated by using both the untreated and the mercerized fibers. Mercerizations of the fibers are done with 1 N solution. The structural properties like tensile, flexural, and impact strengths are experimented as per ASTM and reported. The dry sliding wear study was done using the Pin-on-Disc apparatus as per ASTM G99. In particular, more emphasis has been devoted for wear behaviors at different velocity conditions and loads. Based on the experimental data, the optimum sliding velocity and the corresponding load were suggested.
The effect of patient education on glycemic status and self-monitoring activity in type 2 diabetic patients recently switched to basal insulin analogue treatment
Authors: Hidvégi Tibor , Kovács Gábor
Published: October 2014

Introduction: In addition to medications, patient education is thought to have important beneficial effects in the management of patients with type 2 diabetes mellitus. Aim: The aim of the authors was to evaluate the additional effect of patient education on glycemic control and some aspects of lifestyle in a non-interventional study. Method: Patients between the ages of 18 and 75 were involved. Study sites which provided standardized education program recruited educated patients, while sites which provided diabetes counseling recruited control patients. Results: Patients included in the educated group were younger, had an earlier detection of diabetes, and had better baseline glycemic control. Changes of HbA1clevels in the control and educated group arms were –1.41% and –1.23%, (p = 0.277) and the changes of fasting blood glucose levels were –1.89 mmol/L and –1.88 mmol/L (p = 0.854) in the control and educated groups, respectively. The changes in postprandial glucose levels were significantly greater in the control group (–2.88 mmol/L vs. –2.26 mmol/L in the educated group, p = 0.010). Body mass index in the control group did not actually change between baseline and end of study, but it decreased significantly in the educated group. In the educated group the number of self-monitoring days and the patients’ physical activity increased between education sessions 1 and 3. Conclusions: The possible reason for baseline differences between the two groups was that younger and more motivated patients with better glycemic control tended to join the education program. Education was associated with beneficial body mass changes but not with improvement in glycemic status. Improved self-monitoring and physical activity can be documented in the group of educated patients. Orv. Hetil., 2014, 155(43), 1713–1721.
Kushner at Colonus: Tragedy, Politics, and Citizenship
Authors: Kornhaber David
Published: October 2014

The epilogue of Tony Kushner's Angels in America is often criticized as modeling a political capitulation, allowing vague spiritual promise to eclipse real political difference. This article reads Kushner's epilogue in dialogue with Sophocles's Oedipus at Colonus as a negotiation with the tragic condition that intertwines the political and the spiritual, set in a ritual space of utopian transformation. The plays' tragic subjects, persisting past their expected demise and defined by their continued exclusion from the polis, demand citizenship as an act of reincorporation and an amelioration of suffering, offering transformative benefits to the state in turn. For Kushner, following Sophocles, the demand for citizenship is a demand for personal and political subjecthood, a precondition to all other politics and always a spiritual transfiguration.
Beckett's Tragic Pantry: Endgame and the Deflation of the Act
Authors: Halpern Richard
Published: October 2014

Modern tragedy faces a number of challenges, many of them compiled in George Steiner's classic study The Death of Tragedy. This essay will add one more to Steiner's list: a crisis of action inaugurated by the rise of capitalism and given its first and clearest discursive form in the works of the classical political economists. In The Wealth of Nations, Adam Smith suggests that the prevalence of happiness or its opposite depends less on ethicopolitical actions than it does on economic production. Nations are wealthy or poor, and thus happy or not, according to how efficiently their populations make things, not how wisely or virtuously their members comport themselves. And for the individual, happiness comes to depend more on consumption than on the exercise of virtue, as it had formerly done in Aristotelian ethics. But if tragedy is, as Aristotle claimed, the imitation of an action, then the dethroning of action by production will simultaneously degrade the very substance of tragic drama. What happens to tragedy when the thing that constitutes it is diminished under conditions of capitalist modernity?
Water supply and mining: the policy paradox in Ghana
Authors: Appiah Divine O. , Abass Kabila
Published: October 2014

Ghana has been highly successful in mining for over a century. However, one area of concern is the negative impact of mining activities on water resources: their quality and quantity. Mining companies are guided by rules and regulations, particularly those that have to do with the quality of water supply. Safe water supply is essential for improved health and quality of life for increased productivity. Yet, water supply in mining communities has not assumed the critical importance that it deserves toward the realization of human health security. A combination of key informant interviews and a copious desk-top study of official documentary reports were analysed in the context of the polluter-pays principle. The paper interrogates the corporate social responsibility ambivalence that arises from fresh water contamination during the extraction of mineral resources in the western mining region of Ghana. In spite of some efforts at addressing this problem through corporate social responsibilities, communities affected by mining still question the professed sensitivity of mining companies to their plight with respect to their inalienable right to water supply.
Water management problems in the Copiapó Basin, Chile: markets, severe scarcity and the regulator
Authors: Bitran Eduardo , Rivera Pedro , Villena Marcelo J.
Published: October 2014

This research focuses on the determination of the factors that led to the failure of water management in the Copiapó Basin in Chile. Interestingly, the existence of full private ownership and free tradability of water rights has not prevented the overexploitation of groundwater resources. In the paper, firstly, water regulation and the role of the regulator in Chile are briefly discussed. Secondly, the evolution of water resources in the Copiapó region is characterized and analyzed, and the granting of water use rights in the basin in the last 30 years is concisely described. Thirdly, we examine and analyze prices and quantities traded in the water market of the Copiapó region. We will argue that this crisis is a consequence first of failure in regulatory implementation and second of an extremely rigid regulatory framework that leaves limited room for adjustment to changing conditions, especially regarding the emergence of new information concerning water availability. We believe this investigation is not only relevant for this case in particular, but also for other regions and countries where water markets are in place.
Assessing long-term water quality impacts of reducing phosphorus fertilizer in a US suburban watershed
Authors: Qiu Zeyuan , Prato Tony , Wang Hongmei
Published: October 2014

Phosphorus run-off from urban lawn care is a significant water quality concern in many US suburban communities. Many state and municipal governments in the USA adopt urban fertilizer laws or ordinances that prohibit the use of phosphorus-containing lawn fertilizers. This study assesses the long-term water-quality impacts of two phosphorus-reduction scenarios in a suburban watershed in Central New Jersey. While Scenario I reduces the phosphorus fertilizer application rates by 25%, Scenario II completely eliminates phosphorus fertilizer for urban lawns as required by such laws, rules or ordinances. The long-term water-quality impacts were estimated using the Soil and Water Assessment Tool and then compared to the total maximum daily load (TMDL) water-quality standards using the load duration curve approach. Scenario I will decrease total phosphorus (TP) load to streams by 15.34%. Scenario II achieves greater reduction in TP load to streams than Scenario I, but results in excessive nitrogen run-off and violation of the TMDL standard for total nitrogen. While many regulatory measures focus on reducing phosphorus run-off by prohibiting the use of phosphorus in urban lawn fertilizer, they should be carefully implemented to balance the nutrient needs to maintain healthy lawns and avoid such unintended consequences.
Water rate to manage residential water demand with seasonality: peak-load pricing and increasing block rates approach
Authors: Molinos-Senante María
Published: October 2014

A strong seasonal demand for water occurs in many tourist areas, which might exacerbate the water shortage problems. Water pricing is a key instrument for water use management; therefore, the objective of this work was to design a variable water rate to examine the seasonal water demand in water-scarce regions. The proposed water rate combines the peak-load pricing (PLP) and increasing block rate (IBR) strategies. PLP results in full cost recovery of urban water services; however, IBRs penalise excessive water consumption. Moreover, the proposed water rate structure allocates the costs among users depending on their consumption. Subsequently, an empirical application was developed for a Spanish tourist town illustrating the usefulness of the water rate proposed. In conclusion, the combination of the PLP and IBR approaches is a useful water-pricing strategy for increasing the sustainability of the urban water supply under the conditions of seasonal water demand and water shortage.
Sulfate ion (SO42−) release from old and new cation exchange resins used in condensate polishing systems for power plants
Authors: Zhu Zhi-ping , Tang Xue-ying , Yin Zhao-hui , Yu Wei-wei
Published: October 2014

In this study, a dynamic cycle test, a static immersion method and a pyrolysis experiment were combined to examine the characteristics of SO42− released from several new and old cation exchange resins used in condensate polishing systems for power plants. The results show that the quantity and velocity of SO42− released from new and old resins tend to balance in a short time during the dynamic cycle experiment. SO42− is released by 1500H (monosphere super gel type cation exchange resins) and 001 × 7 (gel type cation exchange resins) new and old cation exchange resins, the quantity of which increases according to immersion time. In the pyrolysis experiment, the quantity of SO42− released from resins increases and the pH of the pyrolysis solution transforms from alkaline to acidic with an increase in temperature.
Enhancing the hydrophobicity of mangrove bark by esterification for oil adsorption
Authors: Asadpour Robabeh , Sapari Nasiman Bin , Isa Mohamed Hasnain , Orji Kalu Uka
Published: October 2014

Oil spills generally cause worldwide concern due to their detrimental effects on the environment and the economy. An assortment of commercial systems has been developed to control these spills, including the use of agricultural wastes as sorbents. This work deals with raw and modified mangrove barks (Rhizophora apiculata), an industrial lignocellulosic waste, as a low cost adsorbent for oil-product-spill cleanup in the aquatic environment. Mangrove bark was modified using fatty acids (oleic acid and palmitic acid) to improve its adsorption capacity. The oil sorption capacity of the modified bark was studied and compared with that of the raw bark. Kinetic tests were conducted with a series of contact times. The influence of particle size, oil dosage, pH and temperature on oil sorption capacity was investigated. The results showed that oleic acid treated bark has a higher sorption capacity (2,860.00 ± 2.00 mg/g) than untreated bark for Tapis crude oil. A correlation between surface functional groups, morphology and surface area of the adsorbent was studied by Fourier transform infrared spectrum, field emission scanning electron microscopy images and Brunauer–Emmett–Teller analysis. Isotherm study was conducted using the Langmuir and Freundlich isotherm models. The result showed that adsorption of crude oil on treated mangrove bark could be best described by the Langmuir model.
Rapid small-scale column testing of granular activated carbon for organic micro-pollutant removal in treated domestic wastewater
Authors: Zietzschmann F. , Müller J. , Sperlich A. , Ruhl A. S. , Meinel F. , Altmann J. , Jekel M.
Published: October 2014

This study investigates the applicability of the rapid small-scale column test (RSSCT) concept for testing of granular activated carbon (GAC) for organic micro-pollutants (OMPs) removal from wastewater treatment plant (WWTP) effluent. The chosen experimental setup was checked using pure water, WWTP effluent, different GAC products, and variable hydrodynamic conditions with different flow velocities and differently sized GAC, as well as different empty bed contact times (EBCTs). The setup results in satisfying reproducibility and robustness. RSSCTs in combination with WWTP effluent are effective when comparing the OMP removal potentials of different GAC products and are a useful tool for the estimation of larger filters. Due to the potentially high competition between OMPs and bulk organics, breakthrough curves are likely to have unfavorable shapes when treating WWTP effluent. This effect can be counteracted by extending the EBCT. With respect to the strong competition observed in GAC treatment of WWTP effluent, the small organic acid and neutral substances are retained longer in the RSSCT filters and are likely to cause the majority of the observed adsorption competition with OMPs.
Research on the characteristics of the water quality of rainwater runoff from green roofs
Authors: Gong Kena , Wu Qing , Peng Sen , Zhao Xinhua , Wang Xiaochen
Published: October 2014

This paper investigates the water quality characteristics of rainwater runoff from dual-substrate-layer green roofs in Tianjin, China. The data were collected from four different assemblies and three types of simulated rains. The storm-water runoff quality was monitored from early June through late October 2012 and from July through late November 2013. The results revealed that the runoff water quality would be improved to some extent with the ageing of green roofs and that the quality retention rate better reflected the pollutant retention capacity of the green roof than the pollutant concentration in the runoff water. The investigation clearly demonstrated that green roofs also effectively reduced the chemical oxygen demand and turbidity value and neutralised acid rain to stabilise the pH of the runoff.
Highly efficient removal of chromium(VI) from aqueous solution using polyaniline/sepiolite nanofibers
Authors: Chen Jun , Hong Xiaoqin , Xie Qingdong , Li Diankai , Zhang Qianfeng
Published: October 2014

Polyaniline/sepiolite (PANI/sepiolite) nanofibers were prepared by in situ chemical oxidation polymerization in the presence of sepiolite. The effect of aniline/sepiolite weight ratio on the nanostructure of PANI/sepiolite composites was investigated by field-emission scanning electron microscopy. The adsorption of Cr(VI) onto the PANI/sepiolite nanofibers was highly dependent on pH values. The pseudo-second-order and Langmuir isothermal models can well describe the adsorption kinetics and adsorption isotherm, respectively. The maximum adsorption capacity of the PANI/sepiolite nanofibers for Cr(VI) was up to 206.6 mg/g at 25 °C and increased with the increase in temperature. Desorption experiments indicated that PANI/sepiolite can be regenerated and reused for two consecutive cycles with no loss of its removal efficiency. PANI/sepiolite nanofibers can be used as a highly efficient and economically viable adsorbent for Cr(VI) removal due to their excellent adsorption characteristics.
Microscopic characteristic of biological iron sulfide composites during the generation process and the association with treatment effect on heavy metal wastewater
Authors: Yang Yang , Xie Yifei , Li Xudong , Zhou Jingchao , Liu Jingwei
Published: October 2014

Heavy metal pollution is a serious environmental concern worldwide, resulting in both environmental and human harm. Recently, studies have shown that environmental biotechnologies based on sulfate reduction offer a potential for removal of toxic heavy metals. Biological iron sulfide composites are iron sulfide compounds generated in situ by sulfate-reducing bacteria. In this study, microscopic morphological changes during the composites' generation process were studied, and the effect of biological iron sulfide composites in different generation phases on treatment of heavy metal wastewater was investigated to establish the correlation between macro-effect and micro-properties. The results revealed that the generation process of biological iron sulfide composites occurs in three phases: the formation phase, stationary phase, and agglomeration phase. The stationary phase can be divided into a pre-stationary phase and post-stationary phase. It was found that the best treatment time for Cr6+ is in the pre-stationary phase, while the best treatment time for Cu2+and Cd2+ is in the post-stationary phase. The results of this study further prove the benefits of treatment of heavy metal wastewater using biological sulfide composites and provide theoretical guidance in practical applications.
Determination of the ozone volumetric mass transfer coefficient in bubble column with two-fluid nozzle gas distributor
Authors: Djekovic-Sevic Milica , Boskovic-Vragolovic Nevenka , Takic Ljiljana , Garic-Grulovic Radmila , Pejanovic Srdjan
Published: October 2014

Experimental investigation of gas-liquid mass transfer of ozone in water, in
bubble column with two-fluid nozzle gas distributor (BKDM), under different
operating conditions, are presented in this work. The main objective was to
determine the ozone volumetric mass transfer coefficient, kL a, in calm
uniform section of the column, under different values of gas and liquid flow
rates. Obtained values of these coefficients were compared with the values in
countercurrent bubble column. The critical liquid flowrate, when gas hold up
reaches its maximum, was experimentally determined. It was shown that the
maximum value of the ozone volumetric mass transfer coefficient is obtained
just when liquid flowrate is at its critical value.
Effect of heat treatment on structural changes in metastable AlSi10mg alloy
Authors: Jordovic B. , Nedeljkovic B. , Mitrovic N. , Zivanic J. , Maricic A.
Published: October 2014

This paper presents a study on structural changes occurring in a rapidly
quenched metastable AlSi10Mg alloy during heating cycles within the
temperature range from room temperature to 800 K. Measurement of electrical
resistivity of a ribbon showed that structural stabilization takes place at
temperatures ranging from 450 K to 650 K. The isotherms of the electrical
resistivity measured at temperatures 473 K, 483 K and 498 K revealed two
stages of structural stabilization i.e. a kinetic process and diffusion
process. Measurement of the thermoelectromotive force of the thermocouple
made from the investigated alloy and a copper conductor by a mechanical
joining was used to determine relative changes in the electron density of
states of the quenched sample after successive heat treatments. The same
alloy sample was subjected to successive heat treatments at temperatures up
to 503 K, 643 K, 683 K and 763 K. The change in the thermopower suggested
that each heating was followed by an increase in free electron density in the
alloy. Therefore, the abrupt decline in electrical resistivity was induced by
an increase in both the mean free electron path and free electron density
during the thermal stabilization of the structure.
Electrochemical deposition of La-Mg alloys in LaCl3-MgCl2-KCl system with molten salt electrolysis process
Authors: Sahoo Kumar , Singh H. , Krishnamurthy N.
Published: October 2014

La-Mg alloys of different compositions were prepared by electrolysis of
LaCl3-MgCl2-KCl melts. Different phases of La-Mg alloys were characterized by
X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Energy
dispersive spectrometry (EDS) and Inductively Coupled Plasma-Atomic Emission
Spectroscopy (ICP-AES) analyses showed that chemical compositions of La-Mg
alloys were consistent with phase structures of XRD pattern, and magnesium
content in the alloy could be controlled by electrolysis parameters. The
effects of various process parameters such as concentration of magnesium
chloride in the bath, temperature of electrolysis and cathode current density
on the current efficiency have been investigated. A maximum current
efficiency of 85% and yield of 80% was obtained from the bath at 12.5A/cm2
current density at an operating temp 850?C.
Influences of different components on viscosities of CaO-MgO-Al2O3-SiO2 melts
Authors: Zhang G.H. , Chou K.C. , Lv X.Y.
Published: October 2014

The present study is aimed to distinguish the different influences of CaO and
MgO, as well as Al2O3 and SiO2 on viscosity of CaO-MgO-Al2O3-SiO2 melts. It
is found that for melt without Al2O3, viscosity increases monotonously as CaO
is gradually replaced by MgO. The addition of Al2O3 leads to a complex
variation of viscosity. In different composition ranges, viscosity may
exhibit different variation tendencies as changing the relative contents of
CaO and MgO while keeping contents of other components constant. It is also
found that when replacing SiO2 by equivalent mole of Al2O3, (i) in CaOAl
2O3-SiO2 system, viscosity increases when Al2O3 content is small relative to
CaO content (there are enough Ca2+ ions to charge compensate Al3+ ions), but
decreases when CaO content is inadequate for charge compensation; (ii) in
MgO-Al2O3-SiO2 system, viscosity always decreases as substituting Al2O3 for
SiO2. The reason for this difference for two systems may be resulted from the
weak charge compensation ability of Mg2+ ion for Al3+ ion relative to Ca2+
ion. All the viscosity variations can be interpreted well by our new proposed
viscosity model.
Influence of Ceramic Thickness and Ceramic Materials on Fracture Resistance of Posterior Partial Coverage Restorations
Authors: Bakeman EM , Rego N , Chaiyabutr Y , Kois JC
Published: October 2014

This study evaluated the influence of ceramic thickness and ceramic materials on fracture resistance of posterior partial coverage ceramic restorations. Forty extracted molars were allocated into four groups (n=10) to test for two variables: 1) the thickness of ceramic (1 mm or 2 mm) and 2) the ceramic materials (a lithium disilicate glass-ceramic [IPS e.max] or leucite-reinforced glass ceramic [IPS Empress]). All ceramic restorations were luted with resin cement (Variolink II) on the prepared teeth. These luted specimens were loaded to failure in a universal testing machine, in the compression mode, with a crosshead speed of 1.0 mm/min. The data were analyzed using two-way analysis of variance and the Tukey Honestly Significantly Different multiple comparison test (α =0.05). The fracture resistance revealed a significant effect for materials (p<0.001); however, the thickness of ceramic was not significant (p=0.074), and the interaction between the thickness of ceramic and the materials was not significant (p=0.406). Mean (standard deviation) fracture resistance values were as follows: a 2-mm thickness of a lithium disilicate bonded to tooth structure (2505 [401] N) revealed a significantly higher fracture resistance than did a 1-mm thickness of leucite-reinforced (1569 [452] N) and a 2-mm thickness of leucite-reinforced ceramic bonded to tooth structure (1716 [436] N) (p<0.05). There was no significant difference in fracture resistance values between a lithium disilicate ceramic at 1-mm thickness (2105 [567] N) and at 2-mm thickness. Using a lithium disilicate glass ceramic for partial coverage restoration significantly improved fracture resistance compared to using a leucite-reinforced glass ceramic. The thickness of ceramic had no significant effect on fracture resistance when the ceramics were bonded to the underlying tooth structure.
Solar Electric Propulsion for Discovery-Class Missions
Authors: Oh David Y. , Snyder John Steven , Goebel Dan M. , Hofer Richard R. , Randolph Thomas M.
Published: October 2014

This paper offers a user-centric consolidation and comparison of the full range of government and commercial solar electric propulsion options available in the near term for primary propulsion on deep-space science missions of the class commonly proposed to NASA’s Discovery program. Unlike previous papers, this work does not emphasize feasibility from a mission-analysis perspective. Rather, it emphasizes requirements uniquely imposed by competitively reviewed cost-capped mission proposals, for which system-level flight heritage and cost credibility can trump sheer performance and mission capture. It describes criteria that mission architects and review boards can use to select and evaluate electric propulsion systems, provides descriptions of viable government and commercial electric propulsion system options, describes the modifications needed to adapt commercial electric propulsion systems to deep space, and discusses appropriate methods for costing commercial-based electric propulsion systems. It concludes that the solar electric propulsion systems best suited for Discovery missions have a solid system flight heritage that can meet the requirements for deep space with minimal modifications. Commercially developed electric propulsion systems offer significant heritage potential and, in many cases, the required changes for deep-space application introduce comparatively low technical and cost risk.
Archives of the Dance (24): The Alhambra Moul Collection at the Victoria and Albert Museum
Authors: Pritchard Jane
Published: October 2014

This article in the ‘Archives of the Dance’ series looks at one specific collection held in the Theatre & Performance Collections of the Victoria and Albert Museum, London. At first glance, the Alfred Moul Collection (THM/75) appears a small collection filling only half a dozen archive boxes plus some photographs and press cuttings books. Nevertheless its content is very revealing about the management of the Alhambra Palace of Variety, Leicester Square, during the years 1901–1914, and the ballets created there. It is not exclusively a dance archive but places the work of the theatre's ballet company in the context of variety theatre and the full range of turns presented there. The collection focuses on the final decade of the fifty years from 1864 in which the Alhambra dominated the ballet-scene in London. This final period was a time of decline and competition for the ballet company. The collection reveals the management's awareness of competition and the consequent need to embrace a wide range of genres; the word ballet was used to cover all forms of theatre dance and, as the collection reveals, the wide search for new dance stars for productions; it enhances our knowledge of dance and dancers from France, Russia, America and Denmark as well as our knowledge of dance in Britain immediately before the full impact of the Russian ballet was felt.
Anti-Biofilm and Immunomodulatory Activities of Peptides That Inhibit Biofilms Formed by Pathogens Isolated from Cystic Fibrosis Patients
Authors: De la Fuente-Núñez César , Mansour Sarah , Wang Zhejun , Jiang Lucy , Breidenstein Elena , Elliott Melissa , Reffuveille Fany , Speert David , Reckseidler-Zenteno Shauna , Shen Ya , Haapasalo Markus , Hancock Robert
Published: October 2014

Cystic fibrosis (CF) patients often acquire chronic respiratory tract infections due to Pseudomonas aeruginosa and Burkholderia cepacia complex (Bcc) species. In the CF lung, these bacteria grow as multicellular aggregates termed biofilms. Biofilms demonstrate increased (adaptive) resistance to conventional antibiotics, and there are currently no available biofilm-specific therapies. Using plastic adherent, hydroxyapatite and flow cell biofilm models coupled with confocal and scanning electron microscopy, it was demonstrated that an anti-biofilm peptide 1018 prevented biofilm formation, eradicated mature biofilms and killed biofilms formed by a wide range of P. aeruginosa and B. cenocepacia clinical isolates. New peptide derivatives were designed that, compared to their parent peptide 1018, showed similar or decreased anti-biofilm activity against P. aeruginosa biofilms, but increased activity against biofilms formed by the Gram-positive bacterium methicillin resistant Staphylococcus aureus. In addition, some of these new peptide derivatives retained the immunomodulatory activity of 1018 since they induced the production of the chemokine monocyte chemotactic protein-1 (MCP-1) and suppressed lipopolysaccharide-mediated tumor necrosis factor-α (TNF-α) production by human peripheral blood mononuclear cells (PBMC) and were non-toxic towards these cells. Peptide 1018 and its derivatives provide promising leads for the treatment of chronic biofilm infections and hyperinflammatory lung disease in CF patients.
Analysis of Phenolic and Flavonoid Contents, and the Anti-Oxidative Potential and Lipid Peroxidation Inhibitory Activity of Methanolic Extract of Carissa opaca Roots and Its Fractions in Different Solvents
Authors: Ahmed Dildar , Fatima Khaizran , Saeed Ramsha
Published: October 2014

The objective of the present work was to investigate the anti-oxidative potential of methanolic extract of Carissa opaca roots and its fractions in solvents of different polarities. Total phenolic (TPC) and flavonoid (TFC) contents of methanolic extract were 211.95 ± 0.78 μg/mL gallic acid equivalents (GAE) and 8.35 ± 0.21 μg/mL rutin equivalents (RE), respectively. Ethyl acetate contained the highest amounts of both (TFC, 11.8 ± 0.28 RE; TPC, 342.80 ± 0.42 GAE) followed by chloroform fraction (TFC, 7.50 ± 0.14 RE; TPC, 275.85 ± 0.50 GAE). Extract and fractions displayed remarkable DPPH radical scavenging activity. EC50 values of methanolic extract was 0.88 mg/mL, while that of hexane, chloroform, ethyl acetate, n-butanolic and aqueous fractions were 0.58, 0.38, 0.29, 0.36 and 5.83 mg/mL, respectively, ethyl acetate fraction being most potent. The ethyl acetate fraction also showed the highest activity in terms of reducing power, phosphomolybdate and ABTS assays. All the fractions showed fairly good lipid peroxidation inhibitory activity, which remained almost constant over three days. Based on the results it can be concluded that roots of Carissa opaca contains phytochemicals with exploitable antioxidant, free radical scavenging, and lipid peroxidation inhibitory potential.
Nuclear Transport of Yeast Proteasomes
Authors: Enenkel Cordula
Published: October 2014

Proteasomes are conserved protease complexes enriched in the nuclei of dividing yeast cells, a major site for protein degradation. If yeast cells do not proliferate and transit to quiescence, metabolic changes result in the dissociation of proteasomes into proteolytic core and regulatory complexes and their sequestration into motile cytosolic proteasome storage granuli. These granuli rapidly clear with the resumption of growth, releasing the stored proteasomes, which relocalize back to the nucleus to promote cell cycle progression. Here, I report on three models of how proteasomes are transported from the cytoplasm into the nucleus of yeast cells. The first model applies for dividing yeast and is based on the canonical pathway using classical nuclear localization sequences of proteasomal subcomplexes and the classical import receptor importin/karyopherin αβ. The second model applies for quiescent yeast cells, which resume growth and use Blm10, a HEAT-like repeat protein structurally related to karyopherin β, for nuclear import of proteasome core particles. In the third model, the fully-assembled proteasome is imported into the nucleus. Our still marginal knowledge about proteasome dynamics will inspire the discussion on how protein degradation by proteasomes may be regulated in different cellular compartments of dividing and quiescent eukaryotic cells.
A Note on Distance-based Graph Entropies
Authors: Chen Zengqiang , Dehmer Matthias , Shi Yongtang
Published: October 2014

A variety of problems in, e.g., discrete mathematics, computer science, information theory, statistics, chemistry, biology, etc., deal with inferring and characterizing relational structures by using graph measures. In this sense, it has been proven that information-theoretic quantities representing graph entropies possess useful properties such as a meaningful structural interpretation and uniqueness. As classical work, many distance-based graph entropies, e.g., the ones due to Bonchev et al. and related quantities have been proposed and studied. Our contribution is to explore graph entropies that are based on a novel information functional, which is the number of vertices with distance \(k\) to a given vertex. In particular, we investigate some properties thereof leading to a better understanding of this new information-theoretic quantity.