bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon disulfide biofiltration: Influence of the accumulation of biodegradation products on biomass development
Authors: Rojo Naiara , Muñoz Raul , Gallastegui Gorka , Barona Astrid , Gurtubay Luis , Prenafeta‐Boldú Francesc X. , Elías Ana
Published: February 2012

BACKGROUND: This research has assessed the impact of sulfate accumulation on the performance of two biofilters treating CS2. Both biofilters were packed with a pelletized organic fertilizer and operated in downflow mode (Biofilter A) and flow reversal mode (Biofilter B). The performance of the biofilters after an excessive accumulation of sulfate has also been evaluated.

RESULTS: The excessive accumulation of sulfate and the reduction in the packing material's moisture content resulted in a decrease in the initial high removal efficiency recorded during the first 50 days (approx.) of operation in both biofilters. A recovery strategy based on mixing and washing the packing material led to a sustained RE of 40 ± 9% and 62 ± 11% for Biofilters A and B, respectively. Both biofilters recovered their initial performance after irrigation. A high CO2:EC ratio suggested that secondary oxidation reactions related to heterotrophic bacteria occurred in both bioreactors. The maximum elimination capacity (ECmax) recorded in Biofilters A and B was 11.6 and 16.6 g CS2 m−3 h−1, respectively.

CONCLUSIONS: This study confirmed the capacity biofilters treating CS2 have to recover after sulfate accumulation episodes and the importance of optimized irrigation strategies. The benefit of the flow reversal operating mode was highlighted. Copyright © 2012 Society of Chemical Industry
Meat fatty acid and cholesterol level of free‐range broilers fed on grasshoppers on alpine rangeland in the Tibetan Plateau
Authors: Sun Tao , Liu Zhiyun , Qin Liping , Long Ruijun
Published: February 2012

BACKGROUND: Meat safety and nutrition are major concerns of consumers. The development of distinctive poultry production methods based on locally available natural resources is important. Grasshoppers are rich in important nutrients and occur in dense concentrations in most rangelands of northern China. Foraging chickens could be used to suppress grasshopper infestations. However, knowledge of the fatty acid content of meat from free‐range broilers reared on alpine rangeland is required.

RESULTS: Rearing conditions and diet did not significantly (P > 0.05) affect concentrations of saturated fatty acid (SFA), arachidonic acid, docosahexaenoic acid or the ratio of total n‐6 to total n‐3 fatty acids. Breast muscle of chickens that had consumed grasshoppers contained significantly (P < 0.05) less monounsaturated fatty acid, but the ratio of polyunsaturated fatty acids (PUFA)/SFA and contents of total n‐3, total n‐6 and PUFA were significantly (P > 0.05) higher than intensively reared birds. Compared with meat from intensively reared birds, meat from free‐range broilers had less cholesterol and higher concentrations of total lipid and phospholipids.

CONCLUSION: Chickens eating grasshoppers in rangeland produce superior quality meat and reduce the grasshopper populations that damage the pastures. This provides an economic system of enhanced poultry‐meat production, which derives benefits from natural resources rather than artificial additives. Copyright © 2012 Society of Chemical Industry
Quantitative analysis of perfumes in talcum powder by using headspace sorptive extraction
Authors: Ng Khim Hui , Heng Audrey , Osborne Murray
Published: February 2012

Quantitative analysis of perfume dosage in talcum powder has been a challenge due to interference of the matrix and has so far not been widely reported. In this study, headspace sorptive extraction (HSSE) was validated as a solventless sample preparation method for the extraction and enrichment of perfume raw materials from talcum powder. Sample enrichment is performed on a thick film of poly(dimethylsiloxane) (PDMS) coated onto a magnetic stir bar incorporated in a glass jacket. Sampling is done by placing the PDMS stir bar in the headspace vial by using a holder. The stir bar is then thermally desorbed online with capillary gas chromatography‐mass spectrometry. The HSSE method is based on the same principles as headspace solid‐phase microextraction (HS‐SPME). Nevertheless, a relatively larger amount of extracting phase is coated on the stir bar as compared to SPME. Sample amount and extraction time were optimized in this study. The method has shown good repeatability (with relative standard deviation no higher than 12.5%) and excellent linearity with correlation coefficients above 0.99 for all analytes. The method was also successfully applied in the quantitative analysis of talcum powder spiked with perfume at different dosages.
Inverse gas chromatographic study of the oxidation stability of lubricating base oil via linear solvation energy relationship
Authors: Moustafa Nagy Emam , Eissa Elham Ahmed , Mahmoud Kout El kloub Fars
Published: February 2012

Linear solvation relationship was used as a new approach to follow the oxidation steps of both naphthenic and paraffinic base oils and to compare the resistances of both oils against oxidation. The obtained results demonstrate that the values of solvation of both oils change approximately linearly with the oxidation time at constant temperature. It was found that the values of the constants change by a faster rate on oxidation of the naphthenic base oil compared with their rate of change of paraffinic oil oxidation. The changed values of solvation constants during the course of oxidation can be used to follow the initiation, propagation and termination oxidation steps. Copyright © 2012 John Wiley & Sons, Ltd.
Self‐Assembly of Borane End‐Functionalized Polystyrene Through Tris(1‐pyrazolyl)borate (Tp) Iron(II) Linkages
Authors: Qin Yang , Shipman Patrick O. , Jäkle Frieder
Published: February 2012

Treatment of trimethylsilane‐terminated polystyrenes with BBr3 resulted in the formation of dibromoboryl‐functionalized mono‐ or ditelechelic styrene polymers. Subsequently, the borane moieties were selectively converted to tris(1‐pyrazolyl)borate (Tp) moieties capable of transition metal coordination. These novel telechelic polymers assemble into redox‐active supramolecular polymer structures upon reaction with Fe(II) as indicated by GPC, UV–vis, and cyclic voltammetry studies.
Helical Polymer as Mimetic Enzyme Catalyzing Asymmetric Aldol Reaction
Authors: Zhang Dongyue , Ren Chonglei , Yang Wantai , Deng Jianping
Published: February 2012

This Communication reports optically active helical substituted polyacetylenes which solely catalyzed asymmetric Aldol reaction between cyclohexanone and p‐nitrobenzaldehyde; more importantly the helical structures are found to play crucial roles in the asymmetric catalysis, with a remarkable yield and ee (both up to 80%). A synergic effect is observed between the helical structures in the polymer main chains and the pendent prolinamide moieties for successfully catalyzing the asymmetric reaction. The role of the helical polymer backbones is further verified by tuning the relative helical structure content.
Effects of Block Length in Copolymers Based on Regioregular Oligothiophenes Linked With Electron‐Accepting Units
Authors: Zhang Luozheng , Zhang Yue , Wei Qingshuo , Zhou Erjun , Yang Chunhe , Hashimoto Kazuhito , Tajima Keisuke
Published: February 2012

Copolymers with an alternating structure of regioregular oligo(3‐hexylthiophene) (O3HT) with different lengths and 2,5‐dibutyl‐3,6‐di(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione (DPP) were synthesized through Stille coupling reaction. The light absorption of the copolymers can be rationally tuned to have a broad spectrum across the visible region by adjusting the length of O3HT. Organic solar cells fabricated with the copolymers and PCBM showed a broad photoresponse and a comparable efficiency to that of poly(3‐hexylthiophene) (P3HT):PCBM cells. The external quantum efficiency and fluorescence spectra suggested that the intrachain energy transfer from the O3HT block to the vicinity of the DPP unit could limit the photovoltaic performance of the copolymers.
A large‐scale 19F MRI‐based cell migration assay to optimize cell therapy
Authors: Bonetto F. , Srinivas M. , Weigelin B. , Cruz L. J. , Heerschap A. , Friedl P. , Figdor C. G. , de Vries I. J. M.
Published: February 2012

Adoptive transfer of cells for therapeutic purposes requires efficient and precise delivery to the target organ whilst preserving cell function. Therefore, therapeutically applied cells need to migrate and integrate within their target tissues after delivery, e.g. dendritic cells (DCs) need to migrate to lymph nodes to elicit an antigen‐specific immune response. Previous studies have shown that inappropriate cell delivery can hinder DC migration and result in insufficient immune induction. As migration can be extremely difficult to study quantitatively in vivo, we propose an in vitro assay that reproduces key in vivo conditions to optimize cell delivery and migration in vivo. Using DC migration along a chemokine gradient, we describe here a novel 19 F MR‐based, large‐scale, quantitative assay to measure cell migration in a three‐dimensional collagen scaffold. Unlike conventional migration assays, this set‐up is amenable to both large and small cell numbers, as well as opaque tissue samples and the inclusion of chemokines or other factors. We labeled primary human DCs with a 19 F label suitable for clinical use; (0.5–15) × 106 cells in the scaffolds were imaged sequentially, and migration was assessed using two independent methods. We found no migration with larger numbers of cells, but up to 3% with less than one million cells. Hence, we show that the cell density in cell bolus injections has a decisive impact on migration, and this may explain the limited migration observed using large cell numbers in the clinic. Copyright © 2012 John Wiley & Sons, Ltd.
Rapid Profiling of Intact Glucosinolates in Arabidopsis Leaves by UHPLC‐QTOFMS Using a Charged Surface Hybrid Column
Authors: Glauser Gaetan , Schweizer Fabian , Turlings Ted C. J. , Reymond Philippe
Published: February 2012

Introduction

The analysis of glucosinolates (GS) is traditionally performed by reverse‐phase liquid chromatography coupled to ultraviolet detection after a time‐consuming desulphation step, which is required for increased retention. Simpler and more efficient alternative methods that can shorten both sample preparation and analysis are much needed.

Objective

To evaluate the feasibility of using ultrahigh‐pressure liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry (UHPLC‐QTOFMS) for the rapid profiling of intact GS.

Methodology

A simple and short extraction of GS from Arabidopsis thaliana leaves was developed. Four sub‐2 µm reverse‐phase columns were tested for the rapid separation of these polar compounds using formic acid as the chromatographic additive. High‐resolution QTOFMS was used to detect and identify GS.

Results

A novel charged surface hybrid (CSH) column was found to provide excellent retention and separation of GS within a total running time of 11 min. Twenty‐one GS could be identified based on their accurate mass as well as isotopic and fragmentation patterns. The method was applied to determine the changes in GS content that occur after herbivory in Arabidopsis. In addition, we evaluated its applicability to the profiling of other Brassicaceae species.

Conclusion

The method developed can profile the full range of GS, including the most polar ones, in a shorter time than previous methods, and is highly compatible with mass spectrometric detection. Copyright © 2012 John Wiley & Sons, Ltd.
Tandem Solid Phase Extraction Followed by Online Trapping–Hydrophilic Interaction Chromatography–Tandem Mass Spectrometry for Sensitive Detection of Endogenous Cytokinins in Plant Tissues
Authors: Liu Zhao , Yuan Bi‐Feng , Feng Yu‐Qi
Published: February 2012

Introduction

Cytokinins (CKs) are a group of plant hormones that play pivotal roles at low concentration in plant growth, development and regulatory pathways. In order to study the function, metabolism and signal transduction of CKs, high performance analytical techniques are required for determination of their endogenous levels.

Objective

To develop a highly sensitive, selective and reliable method for identification and quantification of CKs by employing a tandem solid phase extraction (SPE)–online trapping–hydrophilic interaction chromatography (HILIC)–MS/MS method.

Material and methods

The extraction was performed firstly with tandem SPE containing a C18 cartridge and a silica@C8/SO3H cartridge. After CKs were eluted from the silica@C8/SO3H cartridge, the desorption solvent was concentrated and redissolved in H2O and then injected into the online trapping–HILIC‐MS/MS system with (Poly(MAA‐co‐EGDMA)) monolith as the trapping column. Subsequently, trapping, washing, desorption, separation and detection were accomplished automatically on the system.

Results

Good linearities were obtained for eight cytokinins with correlation coefficients (R2) > 0.9964. The limits of detection (LOD; S:N = 3) for the targets ranged from 0.042 to 1.6 pg/mL. Reproducibility of the method was evaluated with intraday and interday relative standard deviations (RSDs) less than 13.4% and the recoveries ranged from 77.3% to 116.3%. The results showed that the LOD of the analytical method were at least one order of magnitude lower compared with other previously reported methods. Furthermore, only 20 mg of plant tissues were required for the quantitative analysis of the major CKs, which is, to the best of our knowledge, the smallest amount reported so far for the determination of endogenous CKs in plant tissues.

Conclusion

The tandem SPE–online trapping–HILIC‐MS/MS method developed in current study provides a powerful tool for the convenient and highly sensitive quantification of the major CKs in plant tissue. Copyright © 2012 John Wiley & Sons, Ltd.
Kinetics and chemical reactions of acetaldehyde stripping and 2‐methyl‐1,3‐dioxolane generation in poly(ethylene terephthalate)
Authors: Kesaboina Sirisha R. , Lofgren Elizabeth A. , Jabarin Saleh A.
Published: February 2012

Poly(ethylene terephthalate) (PET) resins were air stripped at temperatures from 160 to 190°C to monitor changes that occur during reduction of residual acetaldehyde (AA) concentrations. During this process diffusion and generation of AA, 2‐methyl‐1,3‐dioxolane (2MD), ethylene glycol (EG), and water occurred as the molecular weight and crystallinity increased through complex chemical reactions involving polymerization, formation of by‐products, and some degradation at higher temperatures. This process was characterized in terms of time and temperature of stripping, with determination of residual concentrations of AA and other less volatile compounds such as 2MD and EG. Residual AA concentrations continually decreased from their initial values, while concentrations of 2MD decreased initially, then increased, and later decreased with time. Empirical rate constants for resin solid‐state polymerization were determined at the air‐stripping temperatures, and free EG concentrations as well as intrinsic viscosity, density, crystallinity, and color were monitored to aid in studying the kinetics of AA removal. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Long‐term psychological distress in women at risk for hereditary breast cancer adhering to regular surveillance: a risk profile
Authors: den Heijer Mariska , Seynaeve Caroline , Vanheusden Kathleen , Timman Reinier , Duivenvoorden Hugo J , Tilanus‐Linthorst Madeleine , Menke‐Pluijmers Marian BE , Tibben Aad
Published: February 2012

Background

Some women at risk for hereditary breast cancer are at increased risk of psychological distress. In order to tailor support for individual women, the availability of a tool enabling the identification of psychologically vulnerable women at an early stage is warranted. The objectives of this study were (1) to explore long‐term psychological distress in women at risk for hereditary breast cancer adhering to regular surveillance, and (2) to identify women being vulnerable for long‐term psychological distress, defined in terms of a multifactorial risk profile.

Methods

General distress and cancer‐related distress were assessed at baseline (T0) and after 5–8 years (T1) in 197 high‐risk women adhering to breast cancer surveillance. Coping styles, occurrence of breast cancer in the family of origin, breast cancer risk perception, and frequency of breast self‐examination, as assessed at T0, were examined as predictor variables for long‐term distress (T1).

Results

Across time, women reported a significant reduction in intrusion and avoidance. Intrusion levels were increased among women who had lost a first‐degree relative to breast cancer. Predictors of increased long‐term distress were passive and palliative coping styles, excessive breast self‐examination, and overestimation of breast cancer risk. On the other hand, coping through fostering reassuring thoughts was predictive for decreased long‐term distress.

Conclusion

On the basis of the identified risk profile, it is possible to identify vulnerable women at an early stage, who then may be offered additional and individually tailored support. Copyright © 2012 John Wiley & Sons, Ltd.
Scientific rigour in psycho‐oncology trials: why and how to avoid common statistical errors
Authors: Bell Melanie L. , Olivier Jake , King Madeleine T.
Published: February 2012

Objective

It is well documented that statistical and methodological flaws are common in much of the health research literature, including psycho‐oncology. These can have far‐reaching effects, including the publishing of misleading results; the wasting of time, effort, and financial resources; exposure of patients to the potential harms of research and decreased confidence in science and researchers by the public.

Methods

Several of the most common statistical errors and methodological pitfalls that occur in the field of psycho‐oncology are discussed, including those that occur at the design, analysis, reporting and conclusion stages.

Results

Fourteen topics are briefly discussed, explaining why there is a problem and how to avoid it. These include proper approaches to power, clustering, missing data, categorization of continuous variables, subgroup analyses, multiple comparisons, statistical interactions, confidence intervals and correct interpretation of p‐values. Extensive referencing points the reader to more in‐depth explanations.

Conclusions

To increase the scientific rigour in psycho‐oncology, researchers should involve a biostatistician from the beginning of the study and should commit to continuing education on best practices in the fields of statistics and reporting. Copyright © 2012 John Wiley & Sons, Ltd.
Consequence assessment of chlorine release
Authors: Soman Ambalathum para Raman , Sundararaj Gopalswamy , Devadasan Samuel Rajkumar
Published: February 2012

This study deals with the consequence analysis of an accidental release of chlorine from a storage tank in a chlor‐alkali plant. Chlorine is a liquefied gas and is stored in tanks for various uses like the production of textiles, paper products, and so forth. Chlorine is highly toxic and if released accidentally has the potential to kill or injure people in the vicinity of the storage tank. Calculations are used to determine the discharge rate of chlorine in liquid phase, liquid–gas phase, and gas phase. Subsequently, dispersion calculations are used to determine the downwind concentrations in the vicinity of the tank. The probit equation is used to estimate fatalities for the various accident scenarios. These results are used to develop improvement needs and an emergency response plan. © 2012 American Institute of Chemical Engineers Process Saf Prog, 2012
Residual toxicity and sublethal effects of chlorantraniliprole on Plutella xylostella (Lepidoptera: Plutellidae)
Authors: Han Wensu , Zhang Shufa , Shen Fuying , Liu Meng , Ren Chengcai , Gao Xiwu
Published: February 2012

BACKGROUND: The diamondback moth (DBM), Plutella xylostella (L.), is the most important pest of cruciferous vegetables in the world. Chlorantraniliprole is a novel anthranilic diamide insecticide registered for the control of lepidopteran pests. The dose response, residual toxicity and sublethal effects of chlorantraniliprole applied for 48 h at LC10 (0.02 mg L−1) and LC25 (0.06 mg L−1) on P. xylostella were investigated.

RESULTS: Leaf‐dip bioassays showed that chlorantraniliprole had a high level of toxicity against larvae of P. xylostella, and the 48 h LC50 values were 0.23 and 0.25 mg L−1 for a susceptible and field strain respectively. Chlorantraniliprole also had a long‐lasting effect when the larvae were exposed to chlorantraniliprole field sprayed on radish seedlings. Sublethal effects of chlorantraniliprole were indicated by reduced pupation, pupal weight and adult emergence rates. There was also an increase in the duration of female preoviposition period, decreased fecundity and egg hatch and decreased survival rates of the offspring. The mean values of the net reproductive rate (R0), intrinsic rate of increase (rm), finite rate of increase (λ) were significantly lower in the treatment than in control groups.

CONCLUSIONS: These results indicate that chlorantraniliprole is effective against P. xylostella. The sublethal concentrations of chlorantraniliprole may reduce the population growth of P. xylostella by decreasing its survival and reproduction, and by delaying its development. Copyright © 2012 Society of Chemical Industry
Colorimetry and efficiency of white LEDs: Spectral width dependence
Authors: Taylor Elaine , Edwards Paul R. , Martin Robert W.
Published: February 2012

The potential colour rendering capability and efficiency of white LEDs constructed by a combination of individual red, green and blue (RGB) LEDs are analysed. The conventional measurement of colour rendering quality, the colour rendering index (CRI), is used as well as a recently proposed colour quality scale (CQS), designed to overcome some of the limitations of CRI when narrow‐band emitters are being studied. The colour rendering performance is maximised by variation of the peak emission wavelength and relative intensity of the component LEDs, with the constraint that the spectral widths follow those measured in actual devices. The highest CRI achieved is 89.5, corresponding to a CQS value of 79, colour temperature of 3800 K and a luminous efficacy of radiation (LER) of 365 lm/W. By allowing the spectral width of the green LED to vary the CRI can be raised to 90.9, giving values of 82.5 and 370 lm/W for the CQS and LER, respectively. The significance of these values are discussed in terms of optimising the possible performance of RGB LEDs.
Combination Studies of Eucalyptus torelliana F. Muell. Leaf Extracts and Clarithromycin on Helicobacter pylori
Authors: Lawal Temitope O. , Adeniyi Bolanle A. , Moody Jones O. , Mahady Gail B.
Published: February 2012

Helicobacter pylori is a Gram‐negative bacillus that is associated with the development of gastritis and peptic ulcer disease (PUD). In Nigeria, leaf extracts of Eucalyptus torelliana F. Muell. are used in traditional medicine to treat PUD and other gastrointestinal ailments. The additive and synergistic effects of E. torelliana leaf extracts, in combination with clarithromycin, were investigated using two types of H. pylori strains (ATCC 43629, ATCC 43579) and four clinical isolates of H. pylori (Ed, A2, G1‐1, 5514) in the checkerboard assay and the fractional inhibitory concentration (FIC) index. A time–kill study was also performed on the strain ATCC 43579. The results showed that the E. torelliana extract inhibited the growth of all H. pylori strains, and the addition of one of the isolated active compounds, namely compound 2 (a substituted pyrenyl ester) enhanced the activity of clarithromycin. The minimum inhibitory concentration values of clarithromycin and the botanical compound were reduced twofold (from 0.125 to 0.0625 µg/mL and > 100 to 50 µg/mL respectively). A 100% reduction in CFU/mL of H. pylori ATCC 43579 was observed with the combination of 0.25 µg/mL clarithromycin and 100 µg/mL and 200 µg/mL compound 2 after 3 h of exposure. The results of the investigation showed that the combination of botanical compounds and antibiotics may be beneficial in the treatment of H. pylori infections. Copyright © 2012 John Wiley & Sons, Ltd.
Hydroxysafflor Yellow A Attenuates Lymphostatic Encephalopathy‐induced Brain Injury in Rats
Authors: Pan Yan , Zheng Dong‐Yan , Liu Shang‐Ming , Meng Yan , Xu Hong‐Yan , Zhang Qing , Gong Jing , Xia Zuo‐Li , Chen Lian‐Bi , Li Hong‐Yu
Published: February 2012

Hydroxysafflor yellow A (HSYA) is a main chemical component of the flower of Carthamus tinctorius. The present study investigated whether HSYA could attenuate brain injury induced by lymphostatic encephalopathy (LE). This was induced in adult male Wistar rats by cervical lymphatic blockade (CLB). Heart rate variability (HRV) was used as an indirect measurement of the regulatory function of the autonomic nervous system by recording the ECG signals from rats. It was shown that treatment with HSYA (5 mg/kg, i.p.) significantly alleviated the neurological deficits observed in rats with LE. Histological staining revealed that HSYA treatment attenuated LE‐induced cell apoptosis in the rostral ventrolateral medullus (RVLM). Animals in the LE groups exhibited impaired regulatory roles of the autonomic nervous system in cardiovascular function, which was suppressed by pretreatment with HSYA. Additionally, HSYA administration significantly prevented the decrease of endothelial nitric oxide synthase (eNOS) mRNA and protein expression in the RVLM of rats with LE. These findings suggest that HSYA might provide neuroprotection against LE‐induced brain injury and the associated functional alterations, which is likely regulated by the nitric oxide pathway. Copyright © 2012 John Wiley & Sons, Ltd.
Rise and Fall of Oral Health Products with Canadian Bloodroot Extract†
Authors: Vlachojannis Christian , Magora Florella , Chrubasik Sigrun
Published: February 2012

The rhizome of Sanguinaria canadensis (SC, bloodroot) contains an active principle with antimicrobial, antiinflammatory, antioxidative and immunomodulatory effects. For this reason SC extract has been added to toothpastes and mouthwashes in various concentrations. When tested separately, neither the toothpastes nor the mouthwashes with SC extract had any demonstrable clinical effectiveness against dental plaque and gingivitis. Although using them together twice a day seemed more effective than using placebo, more recent studies have shown conflicting results. Preclinical safety studies up to 2000, which did not include studies longer than 6 months, were thought not to indicate any appreciable potential for harm – to the oral mucosa in particular. In 2003, the FDA Subcommittee on Oral Health Care Drug Products for Over‐the‐Counter Human Use concluded from a review that using SC‐containing products is safe. However, for reasons unknown, the review failed to consider publications between 1999 and 2001 that suggested a possible link between the use of SC‐containing products and the pre‐neoplastic lesion, leukoplakia. As it happened, bloodroot had already been removed (in 2001) from the formula of one of the most widely used products in question and the brand has since then disappeared altogether from the worldwide market. Copyright © 2012 John Wiley & Sons, Ltd.
On the security of PPPoE network
Authors: Liu Fanbao , Xie Tao , Feng Yumeng , Feng Dengguo
Published: February 2012

Point‐to‐Point Protocol over Ethernet (PPPoE) is a network protocol for encapsulating PPP frames inside Ethernet frames. It is widely used by commercial Internet service providers to provide Internet surfing for customers who pay bills. In this paper, we analyze the security of PPPoE network. We find that we can easily collect information about both the peers and the PPPoE authentication servers. We can use such information to recover the peer's authentication password by silently impersonating the server, which is undetectable in the network. We impersonate the server in the peers' LAN and get their passwords by hijacking the peers' PPPoE connections and negotiating for using the Password Authentication Protocol (PAP). We further propose an efficient password recovery attack against the Challenge‐Handshake Authentication Protocol (CHAP). We first recover the length of the used password through on‐line queries, based on the weakness of MD5 input pre‐processing. Then, we crack the known‐length password off‐line, using the probabilistic context‐free grammars. We point out that PPPoE cannot be used anymore until all of the weak authentication protocols including PAP, CHAP, and Microsoft CHAP are abolished right now and replaced with more secure Extensible Authentication Protocols. Copyright © 2012 John Wiley & Sons, Ltd.
Confidential information protection system for mobile devices
Authors: Yoo Sang‐Guun , Park Keun‐Young , Kim Juho
Published: February 2012

Mobile devices such as tab devices (e.g. iPad, Galaxy Tab), smart phones, laptops, and ultra‐mobile personal computers (UMPCs) have become very popular as an access point of important information because of benefits such as small size and mobility. However, because of their high probability of loss or theft, it can turn into a point of information leakage. This is the reason why protection mechanism for confidential information stored in mobile devices have become a need. In this paper, a confidential information protection system for mobile devices is proposed, which is composed of a secure file system and a set of protocols. To show the security of our solution, we have performed an analysis of possible attacks. Additionally, we have developed client/server application prototypes using C# to demonstrate its implementation feasibility for a real environment. Copyright © 2012 John Wiley & Sons, Ltd.
Role of perisynaptic parameters in neurotransmitter homeostasis—Computational study of a general synapse
Authors: Pendyam Sandeep , Mohan Ashwin , Kalivas Peter W. , Nair Satish S.
Published: February 2012

Extracellular neurotransmitter concentrations vary over a wide range depending on the type of neurotransmitter and location in the brain. Neurotransmitter homeostasis near a synapse is achieved by a balance of several mechanisms including vesicular release from the presynapse, diffusion, uptake by transporters, nonsynaptic production, and regulation of release by autoreceptors. These mechanisms are also affected by the glia surrounding the synapse. However, the role of these mechanisms in achieving neurotransmitter homeostasis is not well understood. A biophysical modeling framework was proposed, based on a cortico‐accumbens synapse example case, to reverse engineer glial configurations and parameters related to homeostasis for synapses that support a range of neurotransmitter gradients. Model experiments reveal that synapses with extracellular neurotransmitter concentrations in the micromolar range require nonsynaptic neurotransmitter sources and tight synaptic isolation by extracellular glial formations. The model was used to identify the role of perisynaptic parameters on neurotransmitter homeostasis and to propose glial configurations that could support different levels of extracellular neurotransmitter concentrations. Ranking the parameters based on their effect on neurotransmitter homeostasis, nonsynaptic sources were found to be the most important followed by transporter concentration and diffusion coefficient. Synapse, 2012. © 2012 Wiley Periodicals, Inc.
(2, 0) supersymmetry and the light-cone description of M5-branes
Authors: Lambert N. , Richmond P.
Published: February 2012

Abstract

InarXiv:1007.2982a novel system of equations which propagate in one null and four space directions were obtained as the on-shell conditions for the six-dimensional (2, 0) superalgebra. In this paper we show how this system reduces to one-dimensional motion on instanton moduli space. Quantization leads to the previous light-cone proposal of the (2, 0) theory, generalized to include a potential that arises on the Coulomb branch as well as couplings to background gauge and self-dual two-form fields.
Some Paradoxical Results for the Quadratically Weighted Kappa
Authors: Warrens Matthijs J.
Published: February 2012

The quadratically weighted kappa is the most commonly used weighted kappa statistic for summarizing interrater agreement on an ordinal scale. The paper presents several properties of the quadratically weighted kappa that are paradoxical. For agreement tables with an odd number of categories n it is shown that if one of the raters uses the same base rates for categories 1 and n, categories 2 and n−1, and so on, then the value of quadratically weighted kappa does not depend on the value of the center cell of the agreement table. Since the center cell reflects the exact agreement of the two raters on the middle category, this result questions the applicability of the quadratically weighted kappa to agreement studies. If one wants to report a single index of agreement for an ordinal scale, it is recommended that the linearly weighted kappa instead of the quadratically weighted kappa is used.
Crystallization Behavior of Diacylglycerol‐Rich Oils Produced from Rapeseed Oil
Authors: Saitou Katsuyoshi , Mitsui Yuki , Shimizu Masao , Kudo Naoto , Katsuragi Yoshihisa , Sato Kiyotaka
Published: February 2012

We examined the crystallization behavior of high‐melting fractions in liquid oil containing high concentrations of diacylglycerols (DAG >80%) (hereafter referred to as DAG‐rich oil). By differential scanning calorimetry and optical microscopy at moderate cooling rates, crystallization in the DAG‐rich oil was detected at around 6 °C. It was found that the crystallization extent increased with decreasing temperatures of crystallization below 0 °C. A gas chromatographic analysis was performed on the crystallized fractions, which were separated by filtration at different periods of isothermal crystallization at 3 °C. The results indicated that at earlier crystallization periods, the concentrations of 1,3‐disaturated DAG such as palmitic and stearic acid moieties (15 min) and 1,3‐saturated–unsaturated mixed‐acid DAG including oleic acid, palmitic, and stearic acid moieties (15 min–3 h) were predominant. However, the concentrations of 1,3‐diunsaturated DAG including oleic acid moiety increased after a crystallization period of 6 h. To clarify the sequential crystallization process of DAG, we examined the binary mixing behavior of principal DAG components occurring in the rapeseed‐based DAG‐rich oil. It was evident that 1,3‐disaturated DAG, 1,3‐saturated–unsaturated mixed‐acid DAG, and 1,3‐diunsaturated DAG exhibited immiscible behavior. From these data, basic information on the precipitation processes in DAG‐rich oils at chilled temperatures was obtained.
Myoblast Cell Interaction with Polydopamine Coated Liposomes
Authors: van der Westen Rebecca , Hosta-Rigau Leticia , Sutherland Duncan S. , Goldie Kenneth N. , Albericio Fernando , Postma Almar , Städler Brigitte
Published: February 2012

Liposomes are widely used, from biosensing to drug delivery. Their coating with polymers for stability and functionalization purposes further broadens their set of relevant properties. Poly(dopamine) (PDA), a eumelanin-like material deposited via the “self”-oxidative polymerization of dopamine at mildly basic pH, has attracted considerable interest in the past few years due to its simplicity, flexibility yet fascinating properties. Herein, we characterize the coating of different types of liposomes with PDA depending on the presence of oleoyldopamine in the lipid bilayer and the dopamine hydrochloride concentration. Further, the interaction of these coated liposomes in comparison to their uncoated counterparts with myoblast cells is assessed. Their uptake/association efficiency with these cells is determined. Further, their dose-dependent cytotoxicity with and without entrapped hydrophobic cargo (thiocoraline) is characterized. Taken together, the reported results demonstrate the potential of PDA coated liposomes as a tool in biomedical applications.

Supplementary Material

13758_2011_8_MOESM1_ESM.doc (83KB)
Deciphering an Underlying Mechanism of Differential Cellular Effects of Nanoparticles: An Example of Bach-1 Dependent Induction of HO-1 Expression by Gold Nanorod
Authors: Fan Zhenlin , Yang Xiao , Li Yiye , Li Suping , Niu Shiwen , Wu Xiaochun , Wei Jingyan , Nie Guangjun
Published: February 2012

Gold nanoparticles are extensively investigated for their potential biomedical applications. Therefore, it is pertinent to thoroughly evaluate their biological effects at different levels and their underlying molecular mechanism. Frequently, there are discrepancies about the biological effects of various gold nanoparticles among the reports dealing with different models. Most of the studies focused on the different biological effects of various nano-properties of the nanomaterials. We hypothesize that the biological models with different metabolic processes would be taken into account to explain the observed discrepancies of biological effects of nanomaterials. Herein, by using mouse embryo fibroblast cell line (MEF-1) and human embryonal lung fibroblast cell line (MRC-5) as in vitro models, we studied the cellular effects of gold nanorods (AuNRs) coated with poly (diallyldimethyl ammonium chloride) (PDDAC), polyethylene glycol and polystyrene sulfonae (PSS). We found that all three AuNRs had no effects on cellular viability at the concentration of 1 nM; however, AuNRs that coated with PDDAC and PSS induced significant up-regulation of heme oxygenase-1 (HO-1) which was believed to be involved in cellular defense activities in MEF-1 but not in MRC-5 cells. Further study showed that the low fundamental expression of transcription factor Bach-1, the major regulator of HO-1 expression, in MEF-1 was responsible for the up-regulation of HO-1 induced by the AuNRs. Our results indicate that although AuNRs we used are non-cytotoxic, they cell-specifically induce change of gene expression, such as HO-1. Our current study provides a good example to explain the molecular mechanisms of differential biological effects of nanomaterials in different cellular models. This finding raises a concern on evaluation of cellular effects of nanoparticles where the cell models should be critically considered.
Polyethylenimine-Based Amphiphilic Core–Shell Nanoparticles: Study of Gene Delivery and Intracellular Trafficking
Authors: Siu Yuen Shan , Li Lijun , Leung Man Fai , Lee Kam Len Daniel , Li Pei
Published: February 2012

Amphiphilic core–shell nanoparticle, which is composed of a hydrophobic core and a branched polyethylenimine (PEI) shell, has been designed and synthesized as a novel gene delivery nanocarrier. In our previous study, we demonstrated that the core–shell nanoparticle was not only able to efficiently complex with plasmid DNA (pDNA) and protect it against enzymatic degradation, but also three times less cytotoxic, and threefold more efficient in gene transfection than branched 25 kDa PEI. This paper reports our further studies in the following three aspects: (1) the ability of the PEI-based nanoparticles to deliver gene in various mammalian cell lines; (2) intracellular distributions of the nanoparticles and their pDNA complexes in HeLa cells; and (3) incorporation of nuclear targeting agent into the nanoparticle/pDNA complexes to enhance the nuclear targeting ability. The PEI-based nanoparticles were able to transfect both human and non-human cell lines and their transfection efficiencies were cell-dependent. Within our four tested cell lines (MCF-7, BEL 7404, C6 and CHO-K1), gene transfer using PEI-based core–shell nanoparticles displayed gene expression levels comparable to, or even better than, the commercial Lipofectamine™ 2000. Confocal laser scanning microscopy showed that the nanoparticles and their pDNA complexes were effectively internalized into the HeLa cells. The in vitro time series experiments illustrated that both the nanoparticle/pDNA complexes and PEI-based nanoparticles were distributed in the cytoplasmic region after transfection for 10 and 60 min, respectively. Nuclear localization was also observed in both samples after transfection for 20 and 60 min, respectively. Incorporation of the high mobility group box 1 (HMGB1) protein for nuclear targeting has also been demonstrated with a simple approach: electrostatic complexation between the PEI-based nanoparticles and HMGB1. In the in vitro transfection study in MCF-7 cells, the expression level of the firefly luciferase gene encoded by the pDNA increased remarkably by up to eightfold when the HMGB1 protein was incorporated into the nanoparticle/pDNA complexes. Our results demonstrate that the PEI-based core–shell nanoparticles are promising nanocarriers for gene delivery.
Teleology and Final Causation in Aristotle and in Contemporary Science
Authors: Chase Michael
Published: February 2012

ABSTRACT: With a view to suggesting the possible relevance of Aristotelian thought to current notions of complexity and self-organization, studies Aristotle’s notions of teleology and final causation. After a sketch of the historical process by which such notions were finally rejected in the science of Galileo and Newton, attention is drawn to some contemporary trends in philosophy of science that argue for a return to some (modified) versions of the notion of final causation (I. Prigogine, R. Thom, S. Rosen). These arguments are illustrated by the example of Bénard cells, and the theories of Schneider, Kay, and D. Sagan.
The genusMenegazzia(Lecanorales:Parmeliaceae) in Tasmania revisited
Authors: KANTVILAS Gintaras
Published: February 2012

With 30 species, Tasmania is a major area of species diversity in the genusMenegazzia. Seven of these are new to science:M. absconditaKantvilas, known from Tasmania and New Zealand, andM. athrotaxidisKantvilas,M. hypogymnioidesKantvilas,M. petraeaKantvilas,M. ramulicolaKantvilas,M. subtestaceaKantvilas andM. tarkineaKantvilas, all endemic to Tasmania. An identification key, descriptions based exclusively on Tasmanian collections, and detailed discussion of distribution, ecology, chemical composition and inter-species relationships are provided. All literature records ofMenegazziaspecies pertaining to Tasmania are accounted for. New synonyms include:Menegazzia prototypicaP. James andParmelia pertusavar.coskinodesF. Wilson [synonyms ofM. myriotrema(Müll. Arg.) R. Sant.],M. fertilisP. James [a synonym ofM. platytrema(Müll. Arg.) R. Sant.] andParmelia pertusavar.montanaF. Wilson (a synonym ofM. subtestacea). Incorrectly recorded species that should be deleted from the Tasmanian census includeM. castaneaP. James & D. J. Galloway (present on Macquarie Island) andM. testaceaP. James & D. J. Galloway (endemic to New Zealand). The South American species,M. sanguinascens(Räs.) R. Sant., is recorded in Australasia (Tasmania) for the first time, whereas the widespread south-eastern AustralianM. norsticticaP. James is recorded for Western Australia. Salient features of the genus are discussed, including morphology, anatomy and chemistry. The biogeography of the genus is explored briefly. Twelve species (40%) are endemic to Tasmania, a level of endemism unmatched by any other species-rich genus on the island. Twelve species are shared with mainland Australia, eleven are shared with New Zealand, and only four species are shared with southern South America, all of which are sorediate, suggesting they are products of long-distance dispersal.
The development of Psychodiella sergenti (Apicomplexa: Eugregarinorida) in Phlebotomus sergenti (Diptera: Psychodidae)
Authors: LANTOVA LUCIE , VOLF PETR
Published: February 2012

Psychodiella sergenti is a recently described specific pathogen of the sand fly Phlebotomus sergenti, the main vector of Leishmania tropica. The aim of this study was to examine the life cycle of Ps. sergenti in various developmental stages of the sand fly host. The microscopical methods used include scanning electron microscopy, transmission electron microscopy and light microscopy of native preparations and histological sections stained with periodic acid-Schiff reaction. Psychodiella sergenti oocysts were observed on the chorion of sand fly eggs. In 1st instar larvae, sporozoites were located in the ectoperitrophic space of the intestine. No intracellular stages were found. In 4th instar larvae, Ps. sergenti was mostly located in the ectoperitrophic space of the intestine of the larvae before defecation and in the intestinal lumen of the larvae after defecation. In adults, the parasite was recorded in the body cavity, where the sexual development was triggered by a bloodmeal intake. Psychodiella sergenti has several unique features. It develops sexually exclusively in sand fly females that took a bloodmeal, and its sporozoites bear a distinctive conoid (about 700 nm long), which is more than 4 times longer than conoids of the mosquito gregarines.
Schistosomiasis in infants and pre-school-aged children in sub-Saharan Africa: implication for control
Authors: EKPO UWEM F. , OLUWOLE AKINOLA S. , ABE ENIOLA M. , ETTA HANNAH E. , OLAMIJU FRANCISCA , MAFIANA CHIEDU F.
Published: February 2012

Until recently, the epidemiology and control of schistosomiasis in sub-Saharan Africa have focused primarily on infections in school-aged children and to a lesser extent on adults. Now there is growing evidence and reports of infection in infants and pre-school-aged children (⩽6 years old) in Ghana, Kenya, Mali, Niger, Nigeria and Uganda, with reported prevalence from 14% to 86%. In this review, we provide available information on the epidemiology, transmission and control of schistosomiasis in this age group, generally not considered or included in national schistosomiasis control programmes that are being implemented in several sub-Saharan African countries. Contrary to previous assumptions, we show that schistosomiasis infection starts from early childhood in many endemic communities and factors associated with exposure of infants and pre-school-aged children to infection are yet to be determined. The development of morbidity early in childhood may contribute to long-term clinical impact and severity of schistosomiasis before they receive treatment. Consistently, these issues are overlooked in most schistosomiasis control programmes. It is, therefore, necessary to review current policy of schistosomiasis control programmes in sub-Saharan Africa to consider the treatment of infant and pre-school-aged children and the health education to mothers.
“Freedom By A Judgment”: The Legal History of an Afro-Indian Family
Authors: Sachs Honor
Published: February 2012

On May 2, 1771, John Hardaway of Dinwiddie County, Virginia posted a notice in theVirginia Gazetteabout a runaway slave. The notice was ordinary, blending in with the many advertisements for escaped slaves, servants, wives, and horses that filled the classified section of theGazettein the eighteenth century. Like countless other advertisements posted in newspapers wherever slaves were held, Hardaway's advertisement read: “Run away from the subscriber, a dark mulatto man slave named Bob Colemand, 25 years old, tall, slim, and well made, wears his own hair pretty long, his foretop combed very high, a blacksmith by trade, claimed his freedom under pretense of being of anIndianextraction.”
Ethics in Plato's Republic
Authors: Denyer Nicholas
Published: February 2012

Why should I be just? What have I to gain if I am decent, honest, moral, upright, fair and truthful? Other people benefit if I am just, but do I? And doesn't it seem clear that sometimes the benefit that other people receive from my being just is a benefit received at my expense? Perhaps then I have no adequate reason to be just. Perhaps if I have any sense I will not bother.