bluuebunny/crossref_metadata_2025 huggingface dataset:
Cultura como trabalho: reflexões sobre trabalho e vida de artistas ao longo da pandemia de Covid-19 em São Luís
Authors: Dantas Jefferson , Bandeira Arkley Marques , Carvalho Conceição de Maria Belfort de , Cutrim Klautenys Dellene Guedes , Cutrim Ilza do Socorro Galvão
Published: June 2024

Debatemos a temática da cultura e da arte como exercício da profissão e do artista enquanto trabalhador. O objetivo do artigo é evidenciar experiências de artistas no período do novo coronavírus na cidade de São Luís e suas interações sociais em torno de instituições culturais, evidenciando uma série de estratégias individuais e coletivas em busca de reconhecimento profissional. Metodologicamente, realizamos entrevistas com cinco artistas e usamos dados de institutos públicos de pesquisa, isto é, fizemos uso de dados de natureza primária e secundária, explorando aspectos micro e macrossociológicos. A análise dos dados é amparada por autores das Sociologias da Cultura e do Trabalho, fluentes nas dinâmicas atuais da economia criativa. O cotejo das informações analisadas releva, preliminarmente, os seguintes resultados de pesquisa: alta informalidade e intermitência da força de trabalho artístico, a incredulidade dos artistas na gestão cultural pública, necessidade de efetivação de políticas públicas de arte e cultura que supere gestões ocasionais e a importância da coletividade para os enfrentamentos de crises no mundo do trabalho. Conclui-se que análise da produção artístico-cultural é fundamental para entender a insularidade de recursos materiais e simbólicos entre determinados agentes do campo artístico, significando, de um lado, a riqueza propagandeada por políticos, gestores e empresários contrastada com o empobrecimento e adversidades vivenciadas pelos trabalhadores da cultura e das artes ao longo de suas carreiras, do outro.
A retenção de clientes (alunos) de uma instituição de ensino superior no âmbito de um curso de graduação
Authors: Barros Emanuel Victor de Moura Oliveira , Milan Gabriel Sperandio , Cabral Patrícia Martins Fagundes , Brambilla Flávio Régio
Published: June 2024

A retenção de clientes é vista como um aspecto chave para o sucesso das organizações no mercado, o qual é proposto como um dos componentes mais importantes para a consolidação da participação de mercado, do volume de negócios e da sustentabilidade das empresas. Dessa forma, este trabalho aborda a retenção de alunos (clientes) de uma IES no âmbito do curso de graduação em Direito no município de Rio Verde (GO). Para viabilizar a produção de evidências que permitiram alcançar os objetivos definidos para a pesquisa, foi implementada uma pesquisa de natureza qualitativa e de caráter exploratório. Os dados foram coletados em duas etapas, por meio de entrevistas individuais em profundidade e, mediante a realização de grupos focados (focus groups). Os alunos demonstraram muita satisfação com a IES, incluindo sua formação sólida e experiência profissional, considerando um fator relevante para a permanência na instituição. A pesquisa evidenciou que os construtos de cocriação de valor, valor de uso, custos de troca e satisfação desempenham um papel fundamental na manutenção e na satisfação dos estudantes ao longo de sua jornada acadêmica. Além disso, o estudo possibilitou uma compreensão mais abrangente das necessidades e expectativas dos alunos do curso e da instituição investigada.
Assessing the Impact of Climate Change on Global Crop Yields and Farming Practices
Authors: Naik Anand , Jogi Mahantesh , B V Shreenivas
Published: June 2024

Climate change is recognized as one of the most pressing challenges of our time, with profound implications for global food security. This review article delves into the multifaceted impacts of climate change on crop yields and farming practices on a global scale. By synthesizing recent research findings, identifying key challenges and opportunities, and exploring adaptation strategies, this review provides a comprehensive analysis of the complex interplay between climate change and agriculture. The effects of climate change on agriculture are diverse and far reaching. Alterations in weather patterns, including shifts in temperature, precipitation, and frequency of extreme events, pose significant challenges to agricultural productivity and food security. These changes disrupt traditional farming practices, exacerbate water stress, soil erosion, and crop loss, and threaten the livelihoods of millions of farmers worldwide. Additionally, changes in pest and disease dynamics have further compounded the challenges faced by agricultural systems under pressure from climate variability. These challenges, there are opportunities for innovation and adaptation in the agricultural systems. This review highlights the potential of climate-smart agricultural practices such as crop diversification, conservation agriculture, and precision farming to enhance resilience and mitigate the impacts of climate change on crop yields. investments in climate-resilient crop varieties, improved water management techniques, and sustainable land management practices offer pathways for building adaptive capacities and ensuring food security in a changing climate.  addressing the complex challenges of climate change adaptation in agriculture requires concerted action at multiple levels. This review emphasizes the importance of coordinated efforts among policymakers, researchers, farmers, and other stakeholders in developing and implementing effective adaptation strategies. Such strategies should be context-specific, socially equitable, and environmentally sustainable, considering the diverse needs and priorities of different regions and communities. This review underscores the urgent need for coordinated action to build resilient and sustainable food systems in the face of a changing climate. By synthesizing the latest research findings, identifying key challenges and opportunities, and exploring adaptation strategies, this review aims to inform policymakers, researchers, and practitioners about the imperative of addressing climate change’s impacts on agriculture. Only through collaborative and transformative action can we ensure food security for the present and future generations in a rapidly changing world.
Ecologically Based Rodent Management (EBRM): A Promising Approach to Resolving Conflict between Man and Rodent Pest Species in Nigerian Agro-ecosystem
Authors: Badmus Hafiz Ayinde , Awodoyin Rasheed Olufemi , Ala Adeola Adefoluke
Published: June 2024

The rising population of human being and advancement in technology mark the advent of conflict between man and the lower vertebrate species counterpart notably rodent species. Meanwhile, these rodent species cannot be denied the right to live. With introduction of settled Agriculture, natural flora are removed and crops are introduced to create agro-ecosystem within which the biotic components continue to interact, but as pests because of their infringement on what human is producing for the sustenance of his population. This prompted man to wage war against the rodent pest species by using conventional rodent control via the use of synthetic pesticides which poses health and environmental risks.
Though accorded the pest status, these lower vertebrate species serve tremendous ecological roles in the ecosystem. In the light of this, EBRM has been considered as the way forward in the effective management of rodent pest population and is viewed as a strategy that is sustainable, economical, and minimally damaging to the environment. Therefore, this paper was aimed at reviewing ecologically based rodent management (EBRM) as a promising approach to resolving conflict between man and rodent pest species in Nigerian agro-ecosystem.
The Intersection of Hepcidin and Polycystic Ovary Syndrome: A Review of Current Understanding
Authors: PR Athira , D Swathi. , Sukesh  , Pillai Ajita , N.S Delna
Published: June 2024

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting up to 13% of reproductive-age women. It is characterized by a constellation of symptoms including menstrual irregularities, hyperandrogenism, and polycystic ovaries, often intertwined with metabolic disturbances such as insulin resistance and dyslipidemia. Hepcidin is a liver-produced peptide hormone that regulates iron homeostasis, with a significant role in the pathophysiology of PCOS. Hepcidin controls iron absorption and storage by binding to ferroportin, leading to its degradation and reducing iron export from enterocytes and macrophages. In PCOS patients, hepcidin dysregulation is linked to underlying hormonal and metabolic abnormalities, including insulin resistance and hyperandrogenism. Studies consistently demonstrate decreased hepcidin levels in PCOS patients, resulting in altered iron metabolism parameters, such as increased serum iron and ferritin concentrations, leading to iron overload. This iron overload can exacerbate complications like anemia. The relationship between hepcidin, anemia, and PCOS is influenced by several mechanisms. Hyperandrogenism in PCOS inhibits hepcidin synthesis, reducing iron sequestration and increasing serum iron levels, contributing to erythropoiesis and potentially mitigating anemia, while also posing a risk of iron overload. Hyperinsulinemia associated with insulin resistance further decreases hepcidin levels, enhancing dietary iron absorption and increasing serum iron levels. Despite the chronic low-grade inflammation typical in PCOS, which usually increases hepcidin levels, the inflammation may not be sufficient to override the suppressive effects of hyperandrogenism and hyperinsulinemia on hepcidin expression. Oligomenorrhea or amenorrhea in PCOS leads to reduced menstrual blood loss, contributing to iron retention and further influencing hepcidin regulation. Genetic and epigenetic factors also significantly impact hepcidin expression and iron metabolism in PCOS.
Effect of Rhizobium Inoculation with Zinc and Boron Fertilizers on Growth and Yield of Mungbean (Vigna radiata L.)
Authors: Singh Ajai , Dubey Digvijay
Published: June 2024

Mungbean is considered as an extremely nutritious crop possessing a high level of micronutrients. The field experiment was conducted to evaluate the response of growth and yield of Mungbean to zinc, boron and rhizobium inoculation. The experiment was laid out in split-plot design with tree replications during kharif season of 2021 and 2022 at Instructional farm, Kamla Nehru Institute of Physical and Social Sciences Sultanpur, U.P. India. Four levels of zinc (0, 2.5, 5.0 and 7.5 Kg Zn ha-1), three levels of boron (0, 0.5 and 1.0 Kg B ha-1) and two levels of rhizobium i.e. Uninoculated (Control) and inoculated were used in this study. Zinc levels were allocated to the main plots, boron levels in the sub-plot, while Rhizobium inoculation in the sub-sub plot. The results revealed that plant height, number of branches per plant, dry weight, number of nodules and seed and stover yield were higher in mungbean inoculated with Rhizobium inoculation with application of zinc 7.5 kg ha-1 and Application of boron 1.0 kg ha-1. The findings of the current study would improve the growth and yield of mungbean.
Integrated Nutrient Management: A Pathway to Enhanced Growth and Yield in Amaranthus tricolor L.
Authors: Yadav Saurabh , Jangu Rameshwar , Malviya Suraj , Prajapati Jaswant , Das Kalp , Asati K.P.
Published: June 2024

The present study was conducted to determine the effect of different levels of manures, fertilizer, and biofertilizers application, either alone or in combination on seed germination, vigor, and yield of Amaranthus. Recommended rates of organic manures viz., farmyard manure (5 t/ha) and vermicompost (2.5 t/ha) biofertilizers i.e., Azotobacter and Phosphate solubilizing bacteria @ 200g per 10 kg of seed were integrated with the recommended dose of fertilizer @ 60: 40: 20 kg/ha NPK. The experiment was designed with twelve treatments with three replications that were laid out in a randomized complete block design. Results revealed that the treatment T12 which consists of half dose of NPK + half dose of vermicompost + Azotobacter and PSB observed early emergence of seeds (3.60 days) along with higher germination percentages (84.53 percent) as well as vigorous seedlings in terms of vigor index-1 (5.75) and vigor index-2 (5.56). The crop was harvested three times at a height of 20 cm and by the application of treatment T12, plants take minimum time for harvest i.e., 21.65, 30.65, and 41.16 days along with the highest yield i.e., 0.50, 1.15, and 0.85 kg per plot at first second and third harvest respectively. Therefore, it is clear that combining inorganic fertilizers with organic manures could increase soil health in addition to enhancing growth and facilitating consistent nutrition for the Amaranthus crop.
Post-Emergence Chemical Weed Control in Direct Seeded Rice (Oryza sativa L.) in New Alluvial Zone of West Bengal
Authors: Das Saptashree , Ray Manabendra , Barat Subhajit , Roy Aditi Saha
Published: June 2024

Direct seeded rice (DSR) seems to be a viable option under erratic rainfall and water scarcity. Despite several advantages of DSR, weeds are the major biological constraint. Afield experiment was conducted at Central Research Farm, Gayeshpur of Bidhan Chandra Krishi Vishwavidyalaya Mohanpur, Nadia, West Bengal during the kharif season ((July- November) of 2020 and 2021, comprisingnine weed control methods viz. T1- Imazethapyr 10% SL @ 1000 ml ha-1at 15 DAS, T2 - Imazethapyr 10% SL @ 1250 ml ha-1at 15 DAS ,T3- Imazethapyr 10% SL @ 2000 ml ha-1at 15 DAS, T4- Imazethapyr 10% SL @ 750 fb 750 ml ha-1at 15 DAS and 30 DAS, T5- Imazethapyr 10% SL @ 1000 fb 1000 ml ha-1at 15 DAS and 30 DAS, T6- Imazethapyr 10% SL @ 1250 fb 1250 ml ha-1at 15 DAS and 30 DAS, and T7- Imazethapyr 10% SL @ 2000 fb 2000 ml ha-1at 15 DAS and 30 DAS, T8- weed free check (2 times hand weeding at 20 DAS and 40 DAS) and T9- un-treated control (weedy check) along with 3 replicationslaid out in RBD design in herbicide tolerant rice variety Sava 134 was conducted during two consecutive kharif season of 2020 and 2021 at Central Research Farm, Gayeshpur, B.C.K.V., Nadia under new alluvial zone of West Bengal. The experimental results revealed that maximum grain and straw (4.20 and 4.36 t per ha), as well as net return (Rs. 44546per ha) were recorded in double hand weeding (T8), which was at par with Imazethapyr treated plots like T5, T6 and T7. Thus the tedious, time-consuming, and costly hand-weeding can be profitably replaced by the application of Imazethapyr 10% SL @ 1000 fb 1000 ml per ha at 15 and 30 DAS. This weed control methodhas satisfactory performance in DSR exhibiting higher weed control efficiency and no phytotoxicity symptoms to the herbicide tolerant rice crop and increased both grain and straw yields vis-à-vis benefit : cost ratio.
Investigation of Engineering Properties of Black Gram and Horse Gram for the Design of Hopper and Seed Plate of a Pneumatic Planter
Authors: Kumar Amit , P R Jayan
Published: June 2024

Study presents an in-depth evaluation of the engineering properties of Black Gram (Vigna mungo) varieties VBN-6 and ADT-5, and Horse Gram (Macrotyloma uniflorum) varieties KS-2 and Paiyur-2. This is carried out for the design of a pneumatic seed metering unit viz., seed plate and the hopper. Emphasizing the importance of physical and engineering properties, the investigation on moisture content, axial dimensions, gravimetric properties, and key engineering characteristics such as density, porosity and frictional properties provides critical data for optimizing the design and functionality of the pneumatic seed metering unit, including the seed plate and hopper. For black gram, metering plates with 2.1 mm cell diameter were found optimal, whereas horse gram varieties require 3.5 mm diameter with 26 cells. Hopper of 9100 cm3 capacity made of mild steel of 2 mm thickness was developed according to the seed bulk density and flow characteristics. These properties made the pneumatic metering mechanism compatible with pulse seeds and helped to mechanize the pulse sowing.
Influence of Age and Etching Technique on the Microleakage in Class-V Composite Restorations: An In-vitro Study
Authors: Bhullar Kanwalpreet Kaur , Handa Aashish , Khurana Surbhi , Sran Sukhman Singh
Published: June 2024

Aim: The objective of current research was to evaluate the impact of patient’s age on the microleakage in Class-V composite restorations.
Study Design:  Research article.
Methodology: 30 permanent human molars from various age groups (n=10 each) were collected. The teeth were categorized based on age, Group I (less than 30 years), Group II (30-50 years), and Group III (more than 50 years), standardized Class-V tooth preparations were prepared. Subsequently, each group has further two subgroups: selective enamel etching (Sb A) and self-etching (Sb B), using universal adhesive (3M single bond). Following this, restoration of teeth were done using Z350 composite, and microleakage was analysed by dye penetration method via stereomicroscope and corresponding scoring were recorded. Mann- Whitney Test and Kruskal- Wallis Test was done for statistical analysis.
Results: The group III subgroup A and B showed highest microleakage (2.40 and 2.80) followed by group II (1.20 and 1.60) and least in group I (0.40 and 0.80) respectively (P<.005). Therefore, more microleakage was seen with self-etch group as compare to selective etch.
Conclusion: Influence of age of patient had significant impact on Class-V restorations. Also, more microleakage was observed in self-etch group as compared to that of selective etch technique.
2. Introduction
Authors: Cross Morag , Dalland Magnar , Moretti Debora
Published: June 2024

The proposed development at Beaverbank Place, Canonmills, Edinburgh led to the excavation of the remains of the 19th-century Beaverbank Tannery. Accompanying historical research allowed the history of the ownership and tenancies of the buildings and various businesses to be traced from 1807 to 1959. This included the early 19th-century Clark’s Mill linen bleachers and the 1868 tannery built by the Johnston family and later leased by family firms of the Pringles and Walkers. A period of abandonment between 1913 and 1915 was followed by the repurposing of the building as a sawmill and cooperage. Part of the site changed again to become a motor garage in 1928.
The remains can be matched well with historic map evidence and appear to relate predominantly to the late 19th-century tannery structures. Remains were found of approximately 100 tanning pits set out in a grid pattern, with further features related to drainage, paving and other structures. Very little environmental or artefactual evidence was recovered to shed light on specific practices, materials used or materials produced.
There were also scant structural remains that could be related to the earlier linen bleachers and to the later motor garage.
3. Historical documentary evidence
Authors: Cross Morag , Dalland Magnar , Moretti Debora
Published: June 2024

The proposed development at Beaverbank Place, Canonmills, Edinburgh led to the excavation of the remains of the 19th-century Beaverbank Tannery. Accompanying historical research allowed the history of the ownership and tenancies of the buildings and various businesses to be traced from 1807 to 1959. This included the early 19th-century Clark’s Mill linen bleachers and the 1868 tannery built by the Johnston family and later leased by family firms of the Pringles and Walkers. A period of abandonment between 1913 and 1915 was followed by the repurposing of the building as a sawmill and cooperage. Part of the site changed again to become a motor garage in 1928.
The remains can be matched well with historic map evidence and appear to relate predominantly to the late 19th-century tannery structures. Remains were found of approximately 100 tanning pits set out in a grid pattern, with further features related to drainage, paving and other structures. Very little environmental or artefactual evidence was recovered to shed light on specific practices, materials used or materials produced.
There were also scant structural remains that could be related to the earlier linen bleachers and to the later motor garage.
Titanium‐Based Anode Materials for Safe Lithium‐Ion Batteries
Authors: Chen Zonghai , Belharouak Ilias , Sun Y.‐K. , Amine Khalil
Published: July 2012

Lithium‐ion batteries have been long considered a promising energy storage technology for electrification of the transportation system. However, the poor safety characteristics of lithium‐ion batteries is one of several technological barriers that hinder their deployment for automobile applications. Within the field of battery research and development, titanium‐based anode materials have recently attracted widespread attention due to their significantly better thermal stability than the conventional graphite anode. In this chapter, the fundamental properties and promising electrochemical performance of titanium‐based anode materials will be discussed for applications in hybrid electric vehicles.
Salivary concentration of progesterone and cortisol significantly differs across individuals after correcting for blood hormone values
Authors: Konishi Shoko , Brindle Eleanor , Guyton Amanda , O'Connor Kathleen A.
Published: July 2012

Between‐individual variation of salivary progesterone (P4) and cortisol levels does not always closely reflect blood hormone concentrations. This may be partly a function of individual differences in salivary hormone excretion. We tested whether time of day at sampling and ethnicity contributed to individual variation in salivary hormones after adjusting for blood hormone levels. Forty‐three Caucasian and 15 Japanese women (18–34 years) collected four sets of matched dried blood spot (DBS) and saliva specimens across a menstrual cycle (N = 232 specimen sets). Linear fixed‐effects (LFE) models were used to estimate the effects of diurnal variation and ethnicity on salivary P4 and cortisol while adjusting for DBS levels. For each hormone, women with exclusively positive or negative residuals (unexplained variance) from the LFE models were categorized as high‐ or low‐saliva‐to‐DBS hormone ratio (SDR; high or low salivary secretors), respectively. We found that salivary P4 (P < 0.05) was significantly higher in early morning compared to the afternoon, after controlling for DBS levels, ethnicity, and BMI. After further adjusting for this diurnal effect, significant individual variation in salivary P4 and cortisol remained: sixteen and nine women, respectively were categorized as low or high salivary secretors for both hormones (P < 0.001), suggesting systematic individual‐specific variation of salivary hormonal concentration. We conclude that when saliva is used to quantify P4 or cortisol levels, time of day at sampling should be controlled. Even with this adjustment, salivary P4 and cortisol do not closely mirror between‐ individual variation of serum P4 and cortisol in a substantial proportion of individuals. Am J Phys Anthropol 149:231–241, 2012. © 2012 Wiley Periodicals, Inc.
Influence of cellulose content on the enzyme activity in the saccharification digests of furfural residues
Authors: Liu H. Q. , Feng Y. , Zhao D. Q. , Jiang J. X.
Published: July 2012

Furfural residues, lignocellulosic residues from commercial furfural production, generally consist of cellulose, lignin, and a rather low amount of residual hemicellulose. They represent the most promising potential sources of biomass that are cheap and readily available in large quantities. Furfural residues with cellulose contents of 51.92%, 68.49%, 83.88%, and 94.92% were hydrolysed by a mixture of cellulase and β‐glucosidase with an enzyme loading rate of 7.5 filter paper units/g and 15 cellobiase units/g of cellulose, respectively. We evaluated the filter paper activities of the digested furfural residues containing various cellulose concentrations. Both adsorption and desorption of the cellulase mixture to the lignocellulosic substrate were compared according to the filter paper activities of the digests. The higher the cellulose content of the lignocellulosic substrate, the higher was the apparent adsorption and desorption of the cellulase mixture; this indicates considerable adsorption between the enzyme and the lignin in the furfural residues. The glucose yield of furfural residues increased incrementally according to the cellulose content of the substrate. The highest glucose yield was obtained from the enzymatic hydrolysate of the furfural residue with a cellulose content of 94.92% after a 72‐h saccharification. Furfural residues can be easily hydrolysed to fermentable sugars with mixtures of cellulase and β‐glucosidase. Therefore, furfural residues are potential biomass resources for cellulosic ethanol production. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Immobilization of dill (Anethum Graveolens L.) catalase and its properties
Authors: Arabaci Gulnur , Usluoglu Ayse
Published: July 2012

Over the last decade, enzyme immobilization has become more important in industry and biotechnology. In this study, catalase from dill (Anethum graveolens L.) plant was immobilized covalently with glutaraldehyde onto chitosan particles. The pH and temperature optima as well as the changes in the kinetics of the immobilized and free dill catalase were determined. The Km value for immobilized catalase (35 mM) was higher about 1.5‐fold than that of free enzyme (24 mM). Optimum temperature was observed at 40 °C, a 10 °C higher than that of the free enzyme and was significantly broader. The optimum pH was same for both free and immobilized catalase (pH 7.0). Immobilized catalase showed higher storage stabilities than free catalase. Thermal stability increased with immobilization. Free catalase lost all its activity, whereas immobilized catalase lost 45% of its activity within 60 days incubation period at 4 °C. Free catalase lost all its activity within 5 days, whereas immobilized catalase lost 65% of its activity within 60 days at 25 °C. The remaining activity of the catalase was about 70% after 10 cycles of batch operation. It was observed that operational, thermal and storage stabilities of the enzyme increased with immobilization. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Experimental study on the interaction between lead and serum albumin
Authors: Zuorro Antonio , Lavecchia Roberto
Published: July 2012

The interaction between lead (Pb2+) and bovine serum albumin (BSA) was studied in the temperature range of 10–40 °C through metal‐titration experiments under equilibrium conditions. Lead binding to BSA was monitored by measuring the intensity changes in the difference absorption band at 243 nm following the addition of increasing amounts of lead ions to an aqueous solution at constant protein concentration (2.5 × 10−5 M). The equilibrium binding data were found to be well described by a Langmuir‐type equation, with an almost temperature‐independent saturation value. According to the estimated ΔH0 and ΔS0, the binding of Pb2+ to BSA was both enthalpy‐driven and entropy‐driven, with the entropic contribution providing the major driving force. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Preparation and characterization of lipid vesicles entrapping iron oxide nanoparticles
Authors: Petralito Stefania , Spera Romina , Memoli Adriana , D'Inzeo Guglielmo , Liberti Micaela , Apollonio Francesca
Published: July 2012

Nanometric assemblies, activated and controlled through external stimuli, represent an innovative stage in the development of multifunctional therapeutics. In particular, magnetite nanoparticles embedded in liposomes represent submicrometric carriers that can be activated by external magnetic fields, showing high efficacy in reaching tumor cells offering new exciting opportunities towards the development of active targeting systems. Actually, synthesis and characterization of such nanoscale carriers, as well as the assessment of their entrapment capacity, is of great interest for the scientific community. We report here the formation and the characterization of magnetoliposomes (MLs): phospholipid vesicles encapsulating magnetite nanoparticles. MLs were prepared by embedding hydrophilic nanoparticles of commercially available carboxymethyl‐dextran coated superparamagnetic iron oxide particles inside the vesicles at different lipid/nanoparticles ratios. Liposomes were prepared by the thin lipid film hydration method: a fixed amount of lipids was dissolved in organic solvent and the obtained solution was evaporated until dryness. Then the dry lipid film was hydrated with a buffered aqueous solution of different concentrations of carboxymethyl‐dextran coated magnetite. The resulting MLs, heterogeneous in their size, were extruded through polycarbonate membranes to obtain homogeneous size of unilamellar vesicles. Size exclusion chromatography was used to remove non‐entrapped nanoparticles. Magnetite content was determined by 1,10‐phenanthroline (Kiwada assay) and Belikov methods and also by flame absorption spectrometry. Physical characterization was performed by dynamic light scattering to determine the mean particles diameter, the size distribution, and theζ‐potential. Physical stability of MLs stored at 4 °C was investigated up to 4 weeks to assess the effect on time of the entrapment of the nanoparticles within the liposomes. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Extracorporeal membrane blood oxygenators: effect of membrane wetting on gas transfer and device performance
Authors: Di Paola L. , Terrinoni A. R. , Vitale F.
Published: July 2012

Hollow fiber contactors are successfully used as blood oxygenators in extracorporeal membrane oxygenation (ECMO); the optimization of these devices relies on a full comprehension of transport mechanisms involving respiratory gasses. This phenomenon is not clearly understood although it strongly affects blood oxygenators' performance.

This work presents a model for countercorrent ECMO oxygenators, accounting for both membrane wetting and chemical reactions occurring in these systems. In the first part of the paper, the theoretical framework is presented; later, membrane wetting is analyzed and it is shown its effect on the overall mass transfer coefficients. Namely, it comes to light that membrane wetting strongly reduces membrane performances in terms of gasses transport and of respiratory quotient. Copyright © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Quantitative Structure–Activity Relationship Analysis of a Series of Human Renal Organic Anion Transporter Inhibitors
Authors: Wei Yuhui , Xi Lili , Yao Xiaojun , Li Jiazhong , Wu Xinan
Published: July 2012

Organic anion transporters (OATs) have been proved to play important roles in the membrane transport of numerous potentially toxic xenobiotics, drugs, and endogenous metabolites. In general, OATs substrates can compete with one another for the transporter to mutually decrease renal secretion and thus delay the clearance and prolong the duration of action of each compound. Such interactions have the potential to bring about adverse outcomes for clinical cases. Therefore, it is very important to assess the molecular bioactivity to inhibit OATs during the development of new drugs and co‐administration. In this work, the relationships between 45 chemicals and their corresponding hOAT1 and hOAT3 inhibitory activities were analyzed. The quantitative structure–activity relationship (QSAR) model was developed by genetic algorithm and multiple linear regression method. The predictive power of the proposed model was strictly evaluated, and the applicability domain was also defined. The proposed models were robust and satisfactory and could provide a feasible and effective tool for hOAT1 or hOAT3 inhibitor screening.
Synthesis and Antimicrobial Activities of a Novel Series of Heterocyclic α‐Aminophosphonates
Authors: Abdel‐Megeed Mohamed F. , Badr Badr E. , Azaam Mohamed M. , El‐Hiti Gamal A.
Published: July 2012

Two series of novel α‐aminophosphonates having heterocyclic moieties were synthesized in high yields. The structures of the newly synthesized compounds were confirmed by their elemental analyses, IR, 1H NMR and MS spectral data. These compounds were screened for their antibacterial activities against Escherichia coli (NCIM2065) as a Gram‐negative bacterium, Bacillus subtilis (PC1219) and Staphylococcus aureus (ATCC25292) as Gram‐positive bacteria, and Candida albicans and Saccharomyces cerevisiae as fungi. The minimum inhibitory concentrations (MICs) of the synthesized compounds show high antibacterial and antifungal activities at low concentrations (10–1000 µg/mL). Furthermore, their lethal doses indicated that such compounds are safe for use as antimicrobial agents.
Evaluating four mathematical models for nitrous oxide production by autotrophic ammonia‐oxidizing bacteria
Authors: Ni Bing‐Jie , Yuan Zhiguo , Chandran Kartik , Vanrolleghem Peter A. , Murthy Sudhir
Published: July 2012

There is increasing evidence showing that ammonia‐oxidizing bacteria (AOB) are major contributors to N2O emissions from wastewater treatment plants (WWTPs). Although the fundamental metabolic pathways for N2O production by AOB are now coming to light, the mechanisms responsible for N2O production by AOB in WWTP are not fully understood. Mathematical modeling provides a means for testing hypotheses related to mechanisms and triggers for N2O emissions in WWTP, and can then also become a tool to support the development of mitigation strategies. This study examined the ability of four mathematical model structures to describe two distinct mechanisms of N2O production by AOB. The production mechanisms evaluated are (1) N2O as the final product of nitrifier denitrification with NO as the terminal electron acceptor and (2) N2O as a byproduct of incomplete oxidation of hydroxylamine (NH2OH) to NO. The four models were compared based on their ability to predict N2O dynamics observed in three mixed culture studies. Short‐term batch experimental data were employed to examine model assumptions related to the effects of (1) NH concentration variations, (2) dissolved oxygen (DO) variations, (3) NO accumulations and (4) NH2OH as an externally provided substrate. The modeling results demonstrate that all these models can generally describe the NH, NO, and NO data. However, none of these models were able to reproduce all measured N2O data. The results suggest that both the denitrification and NH2OH pathways may be involved in N2O production and could be kinetically linked by a competition for intracellular reducing equivalents. A unified model capturing both mechanisms and their potential interactions needs to be developed with consideration of physiological complexity. Biotechnol. Bioeng. 2013; 110: 153–163. © 2012 Wiley Periodicals, Inc.
Non-operative management of acute cholecystitis in the elderly
Authors: McGillicuddy E A , Schuster K M , Barre K , Suarez L , Hall M R , Kaml G J , Davis K A , Longo W E
Published: July 2012

Background

Although cholecystectomy is the standard therapy for acute cholecystitis (AC), operative morbidity in the elderly may be high owing to medical co-morbidities and decreased physiological reserve. Outcomes of AC in the elderly have not been fully defined with regard to operative and long-term non-operative management.

Methods

Patients aged 65 years or over admitted to a tertiary care centre with a diagnosis of AC between January 2000 and December 2009 were reviewed retrospectively. Patient data, operative and postoperative details were obtained. To determine cholecystectomy rates in the non-operative group, medical records were reviewed, and patients and families were interviewed.

Results

A total of 290 patients underwent cholecystectomy during the index admission, of whom 59 (20·3 per cent) required conversion to open operation. Fifty-eight of these patients experienced 98 complications, including acute respiratory failure (27), pneumonia (18), myocardial infarction (16) and sepsis (15). Some 185 patients had non-operative treatment, of whom 67 underwent percutaneous cholecystostomy. Forty-four patients subsequently had elective cholecystectomy, with a complication rate of 23 per cent. One hundred and twenty-six patients were discharged without a plan for cholecystectomy; the rate of recurrent AC was 4 per cent among the two-thirds of patients followed to within 15 months of death. No deaths or major complications occurred among those with recurrent AC.

Conclusion

Despite selection of the best elderly candidates for cholecystectomy, postoperative morbidity was significant. Medical management, with interval cholecystectomy only for recurrent AC, may be appropriate in selected patients.
Chemical Proteomics Reveals Heat Shock Protein 60 To Be the Main Cellular Target of the Marine Bioactive Sesterterpene Suvanine
Authors: Cassiano Chiara , Monti Maria Chiara , Festa Carmen , Zampella Angela , Riccio Raffaele , Casapullo Agostino
Published: July 2012

Marine bioactive compounds are potential drug leads because of their diverse pharmacological effects against human diseases. The identification of their cellular targets is crucial for a rational approach to their application in medicinal chemistry. Thus, we have analyzed the cell interactome of suvanine, a sulfated tricyclic terpenoid of marine origin endowed with an interesting anti‐inflammatory activity, by application of a chemical proteomic approach. Heat Shock Protein 60, a chaperone involved in the inflammatory response, is the main cellular target of suvanine, which is also able to interfere with protein chaperone activity, giving evidence for its anti‐inflammatory properties.
Model‐free multivariate curve resolution combined with model‐based kinetics: algorithm and applications
Authors: Sawall Mathias , Börner Armin , Kubis Christoph , Selent Detlef , Ludwig Ralf , Neymeyr Klaus
Published: July 2012

Multivariate curve resolution techniques are powerful tools to extract from sequences of spectra of a chemical reaction system the number of independent chemical components, their associated spectra, and the concentration profiles in time. Usually, these solutions are not unique because of the so‐called rotational ambiguity.

In the present work, we reduce the non‐uniqueness by enforcing the consistency of the computed concentration profiles with a given kinetic model. Traditionally, the kinetic modeling is realized in a separate step, which follows the multivariate curve resolution procedure. In contrast to this, we consider a hybrid approach that combines the model‐free curve resolution technique with the model‐based kinetic modeling in an overall optimization. For a two‐component model problem, the range of possible solutions is analyzed, and its reduction to a single, unique solution by means of the hybrid kinetic modeling is shown. The algorithm reduces the rotational ambiguity and improves the quality of the kinetic fitting. Numerical results are also presented for a multi‐component catalytic reaction system that obeys the Michaelis–Menten kinetics. Copyright © 2012 John Wiley & Sons, Ltd.
Hydrogen Migrations in Alkylcycloalkyl Radicals: Implications for Chain‐Branching Reactions in Fuels
Authors: Davis Alexander C. , Tangprasertchai Narin , Francisco Joseph S.
Published: July 2012

A thorough understanding of the oxidation chemistry of cycloalkanes is integral to the development of alternative fuels and improving current fuel performance. An important class of reactions essential to this chemistry is the hydrogen migration; however, they have largely been omitted from the literature for cycloalkanes. The present work investigates all of the hydrogen migration reactions available to methylcyclopentane, ethylcyclopentane, methylcyclohexane, and ethylcyclohexane. The kinetic and thermodynamic parameters have been studied by a combination of computational methods and compared to their corresponding n‐alkyl and methylalkyl counterparts to determine the effect that the cycloalkane ring has on these reactions. In particular, although the alkylcycloalkyl activation energies for the dominant 1,4, 1,5, and 1,6 H‐migration are higher than in n‐alkyl and methylalkyl radicals, because several of the rotors needed to form the transition state are locked into place as part of the cycloalkane ring, the A‐factors are higher for the alkylcycloalkyl reactions, making the rates closer to the noncyclic systems, at higher temperatures. The results presented here suggest that the relative importance of each H‐migration pathway differs from the trends predicted by either the n‐alkyl or methylalkyl radical systems. Of particular interest is the observation that since the barrier height of the 1,4 H‐migration is only 3–5 kcal mol−1 higher than the 1,5 H‐migration in the methyl and ethylcycloalkyl radicals, compared to a difference of roughly 7 kcal mol−1 in similar reactions for both the n‐alkyl and methylalkyl radicals, the 1,4 H‐migrations in alkylcycloalkyl radicals will be more important in the overall mechanism than would be predicted based on the n‐alkyl and methylalkyl radicals. These results have important combustion model implications, particularly for fuels with high cycloalkane content.
Sensitive Near‐Infrared Fluorescent Probes for Thiols Based on SeN Bond Cleavage: Imaging in Living Cells and Tissues
Authors: Wang Rui , Chen Lingxin , Liu Ping , Zhang Qin , Wang Yunqing
Published: July 2012

Cy‐NiSe and Cy‐TfSe were designed and synthesized as sensitive near‐infrared (NIR) fluorescent probes for detecting thiols on the basis of SeN bond cleavage both in cells and in tissues. Since a donor‐excited photoinduced electron transfer (d‐PET) process occurs between the modulator and the fluorophore, Cy‐NiSe and Cy‐TfSe have weak fluorescence. On titration with glutathione, the free dye exhibits significant fluorescence enhancement. The two probes are sensitive and selective for thiols over other relevant biological species. They can function rapidly at pH 7.4, and their emission lies in the NIR region. Confocal imaging confirms that Cy‐NiSe and Cy‐TfSe can be used for detecting thiols in living cells and tissues.
Dynamic Kinetic Resolution of 2,3‐Dihydrobenzo[b]furans: Chemoenzymatic Synthesis of Analgesic Agent BRL 37959
Authors: Bongen Patrick , Pietruszka Jörg , Simon Robert Christian
Published: July 2012

An efficient asymmetric synthesis of (S)‐2,3‐dihydrobenzo[b]furan‐3‐carboxylic acid (8 a) and (S)‐5‐chloro‐2,3‐dihydrobenzo[b]furan‐3‐carboxylic acid (8 b) was established. Key to the success was the highly stereoselective enzymatic kinetic resolution of the corresponding methyl or ethyl esters that was further developed into a dynamic process. As a reliable and fast tool for analysing the enantiomeric excess, HPLC coupled with a CD detector was utilized. The route was completed by a Friedel–Crafts acylation of ethyl (S)‐5‐chloro‐2,3‐dihydrobenzo[b]furan‐3‐carboxylate (7 c) followed by saponification leading to (S)‐5‐chloro‐2,3‐dihydrobenzo[b]furan‐3‐carboxylic acid (2), an analgesic agent.
Control of Porosity by Using Isoreticular Zeolitic Imidazolate Frameworks (IRZIFs) as a Template for Porous Carbon Synthesis
Authors: Pachfule Pradip , Biswal Bishnu P. , Banerjee Rahul
Published: July 2012

Herein, by using isoreticular zeolitic imidazolate frameworks (IRZIFs) as a template, we report the synthesis, morphology, and gas adsorption properties of porous carbon synthesized by a nanocasting method at 1000 °C, in which furfuryl alcohol (FA) was used as a carbon source. By using IRZIFs with variable porosity as templates, we could achieve control over the carbon porosity and H2 and CO2 uptake. The resultant microporous carbon C‐70, synthesized by using ZIF‐70 as the template, is the most porous (Brunauer–Emmett–Teller (BET) surface area 1510 m2 g−1). Carbon C‐68, synthesized by using ZIF‐68, has moderate porosity (BET surface area 1311 m2 g−1), and C‐69, synthesized by using ZIF‐69, has the lowest porosity in this series (BET surface area 1171 m2 g−1). The porous carbons C‐70, C‐68, and C‐69, which have graphitic texture, have promising H2 uptake capacities of 2.37, 2.15, and 1.96 wt %, respectively, at 77 K and 1 atm. Additionally, C‐70, C‐68, and C‐69 show CO2 uptake capacities of 5.45, 4.98, and 4.54 mmol g−1, respectively, at 273 K and 1 atm. The gas uptake trends shown by C‐70, C‐68, and C‐69 clearly indicate the dependence of carbon porosity on the host template. Moreover, the as‐synthesized carbons C‐70, C‐68, and C‐69 show variable conductivity.
Peptide Chirality Sensing by a Cyclodextrin–Polythiophene Conjugate
Authors: Fukuhara Gaku , Inoue Yoshihisa
Published: July 2012

A new cyclodextrin–polythiophene conjugate (CDPT) has been prepared by attaching permethyl‐α‐cyclodextrins to polythiophene (PT) through a hexamethylene tether. Circular dichroism spectral examination of CDPT revealed that only a weak positive Cotton effect (Δε=0.1 M−1 cm−1) was induced at the main band of the PT in dimethyl sulfoxide and similarly weak bisignate signals in pure and aqueous methanol solutions, which indicates that the α‐cyclodextrins appended to PT with a long tether are ineffective in inducing a homochiral structure in the PT backbone. Nevertheless, enantiomeric amino acids and dipeptides added to an aqueous methanolic solution of CDPT caused chirality‐dependent hypochromic changes in the UV/Vis spectra, which enabled us to sense these species and quantitatively determine the enantioselectivity by observing the difference in absorbance upon interaction with pairs of enantiomers. Enantiomeric d,d/l,l‐dipeptide pairs rather than D/L‐amino acid pairs were better differentiated in general, the highest dd/ll selectivity of 13.7 being observed for Phe‐Phe.
Direct α‐Functionalization of Saturated Cyclic Amines
Authors: Mitchell Emily A. , Peschiulli Aldo , Lefevre Nicolas , Meerpoel Lieven , Maes Bert U. W.
Published: July 2012

Recent advances in synthetic methods for the direct α‐functionalization of saturated cyclic amines are described. Methods are categorized according to the in situ formed reactive intermediate (α‐amino cation, α‐amino anion, and α‐amino radical). Transition‐metal‐catalyzed reactions involving other intermediates have been treated as a separate and fourth class.
Dendritic Metalloporphyrin–Fullerene Conjugates: Changing the Microenvironment around Redox‐Active Centers and its Impact on Charge‐Transfer Reactions
Authors: Krokos Evangelos , Spänig Fabian , Ruppert Michaela , Hirsch Andreas , Guldi Dirk M.
Published: July 2012

Photophysical investigations on a series of (2,4,6)‐tris‐substituted metalloporphyrin‐fullerene conjugates revealed the effects of an electron‐rich microenvironment surrounding the electron‐donating porphyrin as a function of the metal center. On one hand, for all conjugates—water‐soluble and non‐water‐soluble—ultrafast charge separation was observed upon photoexcitation. On the other hand, when examining the charge recombination dynamics for the non‐water‐soluble conjugates it becomes obvious that the (2,4,6)‐tris‐substitution stabilizes the radical‐ion‐pair state relative to the mono‐substitution in the ortho‐, meta‐, and para‐position. The more efficient protection of the electron‐donating porphyrin from solvation is thought to be the major cause for this impact. Nevertheless, the situation is slightly different for the water‐soluble conjugates. At first glance, the radical‐ion‐pair state lifetimes are, also in the case of the (2,4,6)‐tris‐substitution, longer than for the mono‐substituted ortho‐, meta‐ and para‐conjugates. Upon closer inspection, they fail, however, to exhibit any metal dependence. Competing with the protection from solvation of the dendrons, dipole‐charge interactions impact the stabilization in the polar aqueous environment and, in turn, become the dominant force governing the electron‐transfer dynamics.