bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lyophilised Aloe excelsa Fractions, Photo-protection and Actinic Damage Retardation Claims Substantiation
Authors: Chifamba J , Addae A J , Zengeni S , Pomerai M , Kurebgaseka N 
Published: May 2024

Introduction: Ultraviolet radiation is potentially harmful to plants’ physiological structures and their photosynthetic apparatus through induction of photo-oxidative damage and photosynthetic inhibition. Aloe excelsa a resilient (sub) tropical plant has evolved various photo-protective mechanisms to proliferate in these harsh environments. With the current FDA, over-the-Counter Monograph M020 castigating 14 of the 16 approved sunscreens as “unsafe” to the ecology and human health, the hunt for safer sunscreens is on and phytoconstituents from photo-resilient plants may just be the next generation, safe and efficacious sunscreens.
Aims: This study investigated the photo-protective activity of lyophilized hydro-ethanolic Aloe excelsa extracts through phytoscreening and in-vitro estimations of their SPF, UVAPF, UVA/UVB ratio, critical wavelength, anti-oxidancy as well as anti-inflammatory potential.
Methods: The Aloe excelsa gel matrix was physically extracted from transversely cut fresh rossetes, macerated in 70% ethanol, lyophilized and then subjected to both quantitative and qualitative phytochemical screening techniques. The antioxidant activity was measured using the DPPH scavenging assay, the photoprotection investigation was performed in-vitro using directives from COLIPA 2011/FDA Final Rule 2011 as guidelines and the anti-inflammatory capacity was evaluated using the protein denaturing test.
Results: Qualitative phytochemical screening confirmed the presence of numerous primary and secondary metabolites of pharmacological interest, Quantitative phyto-analysis revealed that Aloe excelsa has higher levels of total phenols, tannins and flavonoids than Aloe vera. Anti-inflammatory capacity was closely related to the standard Diclofenac and the anti oxidancy was almost equivalent to ascorbic acid. A prepared 50% Aloe excelsa gel had an SPF of 7.6 and a UVAPF of 4 and a critical wavelength of 375. The calculated photostabilities: %SPFeff and %UVAPFeff were both above 97%.
Conclusion: The results confirm that Aloe excelsa is a multifunctional photoprotective material with confirmed anti-oxidancy, anti-inflammatory and UVR protection attributes. The 50% lyophilised Aloe excelsa gel can be technically classified as a low SPF sunscreen. The abundant primary and secondary metabolites correlate directly with the observed and calculated photoprotective parameters obtained in this study.
Investigating Solution‐Phase Protein Structure and Dynamics by Hydrogen Exchange Mass Spectrometry
Authors: Morgan Christopher R. , Engen John R. 
Published: November 2009

AbstractBy taking advantage of labeling methods such as hydrogen exchange (HX), many details about protein conformation, dynamics, and interactions can be revealed by mass spectrometry. In this unit, hydrogen exchange theory is discussed as it applies to HX‐MS protocols, the practice of HX‐MS including data analysis and interpretation is explained in detail, and recent advancements in technology which greatly increase the depth of information gained from the technique are highlighted. Curr. Protoc. Protein Sci. 58:17.6.1‐17.9.17. © 2009 by John Wiley & Sons, Inc.
Introduction to Atomic Force Microscopy (AFM) in Biology
Authors: Goldsbury Claire S. , Scheuring Simon , Kreplak Laurent 
Published: November 2009

AbstractThe atomic force microscope (AFM) has the unique capability of imaging biological samples with molecular resolution in buffer solution. In addition to providing topographical images of surfaces with nanometer‐ to angstrom‐scale resolution, forces between single molecules and mechanical properties of biological samples can be investigated from the nanoscale to the microscale. Importantly, the measurements are made in buffer solutions, allowing biological samples to “stay alive” within a physiological‐like environment while temporal changes in structure are measured—e.g., before and after addition of chemical reagents. These qualities distinguish AFM from conventional imaging techniques of comparable resolution, e.g., electron microscopy (EM). This unit provides an introduction to AFM on biological systems and describes specific examples of AFM on proteins, cells, and tissues. The physical principles of the technique and methodological aspects of its practical use and applications are also described. Curr. Protoc. Protein Sci. 58:17.7.1‐17.7.19. © 2009 by John Wiley & Sons, Inc.
Costs and benefits of dropout schedules of test–restudy practice: Implications for student learning
Authors: Pyc Mary A. , Rawson Katherine A. 
Published: November 2009

AbstractAlmost all previous studies examining the benefits of testing for promoting student learning have used fixed schedules of practice. However, students more often report utilizing a dropout schedule of practice, in which items are dropped from practice once they are known. Two experiments investigated the costs and benefits of utilizing a dropout schedule of test–restudy practice. Participants learned Swahili–English paired associates using a dropout schedule or a fixed schedule. In thedropoutschedule, items received test–restudy practice until each item was correctly recalled once. In thefixedschedule, all items received three tests–restudy practice trials regardless of whether they were correctly recalled, as in previous research. Experiment 2 also included a second learning session. In both experiments, a final cued recall test was administered several days later. Results indicated that the benefits of the dropout schedule (fewer practice trials used overall and all items correctly recalled once during practice) need to be considered in light of the costs (lower levels of final test performance). Copyright © 2009 John Wiley & Sons, Ltd.
Mug book exposure effects: Retroactive interference or criterion shift?
Authors: McAllister Hunter A. , Blaze John T. , Brandon Crystal A. , Deschamps Joseph D. , Fultyn Christine A. , Parker Christina C. , Salcido Amanda D. , Tarver Christopher D. , Thibodeaux Jennifer L. 
Published: November 2009

AbstractThe purpose of this research was to test whether delay between a mug book task and a lineup task moderates a simple mug shot exposure effect. Following the witnessing of a simulated theft, participants searched either a small, large or no mug book. Participants then viewed a lineup that contained either the perpetrator or an innocent replacement; the lineup occurred either immediately after viewing the mug book or 48 hours later. There were fewer suspect identifications and more lineup rejections in the mug book conditions than the no mug book control; this was explained in terms of the criterion for making choices carrying over from the mug book to the lineup. There was qualified support for delay moderating the mug book exposure effect. Copyright © 2009 John Wiley & Sons, Ltd.
Similarities and differences between the concepts of operability and flexibility: The steady‐state case
Authors: Lima Fernando V. , Jia Zhenya , Ierapetritou Marianthi , Georgakis Christos 
Published: November 2009

AbstractThis article presents a comparative review on the operability and flexibility concepts and their application to process design and control. First, the operability and flexibility methodologies are summarized. Then the application of the operability framework to steady‐state and dynamic systems is illustrated through the examination of several example categories such as linear and nonlinear, square and non‐square systems. The flexibility approach based on the active set strategy is used to study the same examples from the flexibility point of view. The discussed results show that the operability and flexibility approaches examine a process from different perspectives and provide valuable complementary information. © 2009 American Institute of Chemical Engineers AIChE J, 2010
A novel approach to scheduling multipurpose batch plants using unit‐slots
Authors: Susarla Naresh , Li Jie , Karimi I. A. 
Published: November 2009

AbstractSeveral models for scheduling multipurpose batch plants exist in the literature. The models using unit‐specific event points have shown better solution efficiency on various literature examples. This article presents a novel approach to scheduling multipurpose batch plants, which uses unit‐slots instead of process‐slots to manage shared resources such as material storage. We develop two slightly different models that are even more compact and simpler than that of Sundaramoorthy and Karimi, Chem Eng Sci. 2005;60:2679–2702. Although we focus on material as a shared resource, our multi‐grid approach rationalizes, generalizes, and improves the current multi‐grid approaches for scheduling with shared resources. Our models allow nonsimultaneous transfers of materials into and out of a batch. We show by an example that this flexibility can give better schedules than those from existing models in some cases. Furthermore, our approach uses fewer slots (event‐points) on some examples than even those required by the most recent unit‐specific event‐based model. Numerical evaluation using literature examples shows significant gains in solution efficiency from the use of unit‐slots except where the number of unit‐slots required for the optimal solution equals that of process slots. We also highlight the importance of constraint sequencing in GAMS implementation for evaluating mixed‐integer linear programming based scheduling models fairly. © 2009 American Institute of Chemical Engineers AIChE J, 2010
Macrogeographical variability in the great call of Hylobates agilis: assessing the applicability of vocal analysis in studies of fine‐scale taxonomy of gibbons
Authors: Heller R. , Sander A.F. , Wang C.W. , Usman F. , Dabelsteen T. 
Published: November 2009

AbstractVocal characteristics have been used extensively to distinguish different taxonomic units of gibbons (family Hylobatidae). The agile gibbon (Hylobates agilis) has a disjunct distribution range in the Southeast Asian archipelago (remnants of the former Sunda landmass), and populations on different islands are currently recognized as distinct subspecies or even species. We recorded great calls from female agile gibbons from two populations on Sumatra and two populations on Borneo and examined the vocal variability on four levels: within‐individuals, between‐individuals, between‐populations and between‐islands. The primary objective was to evaluate the effect of geographical isolation on variability in song pattern and to test whether proposed island‐specific song characteristics exist, reflecting evolutionary divergence between Sumatran and Bornean agile gibbons. One hundred great calls were recorded from 20 females and analyzed for 18 spectral and temporal acoustic parameters. Principal component analysis followed by a nested ANOVA on components revealed a complex pattern of song variability not likely to reflect taxonomic or evolutionary relationship. We found no evidence that Sumatran and Bornean agile gibbons have evolved different vocal characteristics, refuting a distinction between them based on vocal characteristics. A high level of plasticity was found in great calls from the same individual, and generally the inferred pattern of variability suggested that ecological or social factors may confound any genetically based island dialects. Am. J. Primatol. 72:142–151, 2010. © 2009 Wiley‐Liss, Inc.
High‐fiber diet promotes weight loss and affects maternal behavior in vervet monkeys
Authors: Fairbanks Lynn A. , Blau Karin , Jorgensen Matthew J. 
Published: November 2009

AbstractThe dramatic increase in obesity in western societies has shifted the emphasis in nutrition research from the problems of undernutrition to the adverse consequences of being overweight. As with humans, Old World monkeys are at increased risk for type II diabetes and other chronic diseases when they gain excessive weight. To prevent overweight and obesity, promote animal health, and provide a more natural level of fiber in the diet, the standard commercial monkey chow diet at a vervet monkey breeding colony was changed to a higher fiber formulation in 2004. The new diet was also higher in protein and lower in carbohydrate and energy density than the standard diet. Because maternal behavior is known to be sensitive to differences in resource availability, data on weight and mother–infant interactions for 147 mothers with 279 infants born from 2000 through 2006 were assessed for effects of the diet change. The results showed that, even though food was provided ad libitum, the mean body weight of breeding females was 10% lower after the transition to the high‐fiber diet. Behaviorally, mothers on the high‐fiber diet were significantly more rejecting to their infants, and their infants had to play a greater role in maintaining ventral contact in the first few months of their lives. The effects of the diet change on maternal rejection were significantly related to the mother's body weight, with lower‐weight mothers scoring higher in maternal rejection. These results demonstrate that maternal behavior is responsive to changes in maternal condition, and that beneficial changes in the diet may have unintended consequences on behavior. Am. J. Primatol. 72:234–241, 2010. © 2009 Wiley‐Liss, Inc.
Phylogeny and phylogeography of squirrel monkeys (genusSaimiri) based on cytochromebgenetic analysis
Authors: Lavergne Anne , Ruiz‐García Manuel , Catzeflis François , Lacote Sandra , Contamin Hugues , Mercereau‐Puijalon Odile , Lacoste Vincent , de Thoisy Benoît 
Published: November 2009

AbstractSquirrel monkeys (genusSaimiri) are distributed over a wide area encompassing the Amazon Basin: French Guiana, Suriname, and Guyana, together with Western Panama and Western Costa Rica. The genusSaimiriincludes a complex of species and subspecies displaying considerable morphological variation. Taxonomic and systematic studies have identified, in this genus, one to seven species comprising up to 16 subspecies. The phylogenetic relationships between these taxa are poorly understood. Molecular markers have yielded a consistent framework for the systematics of Central and South AmericanSaimiri, identifying four distinct clades:S. oerstedii,S.sciureus,S.boliviensis, andS.ustus. Here, we reconsider the phylogenetic and biogeographic history ofSaimirion the basis of mitochondrial (mtDNA) sequence data, focusing mostly on individuals originating from the Amazon Basin. We studied 32 monkeys with well‐defined geographic origins and inferred the phylogenetic relationships between them on the basis of full‐length cytochromebgene nucleotide sequences. The high level of gene diversity observed (0.966) is consistent with the high level of behavioral and morphological variation observed across the geographic range of the genus: 20 mtDNA haplotypes were identified with a maximum divergence of 4.81% betweenS. b. boliviensisandS. ustus. In addition to confirming the existence of the four clades previously identified on the basis of molecular characters, we suggest several new lineages, includingS. s. macrodon,S. s. albigena,S. s. cassiquiarensis, andS. s. collinsi.We also propose new patterns of dispersion and diversification for the genusSaimiri, and discuss the contribution of certain rivers and forest refuges to its structuring. Am. J. Primatol. 72:242–253, 2010. © 2009 Wiley‐Liss, Inc.
Isothiocyanate derivatives of soybean oil triglycerides: Synthesis, characterization, and polymerization with polyols and polyamines
Authors: Çaylı Gökhan , Küsefoğlu Selim 
Published: November 2009

AbstractIn this article, a novel two step synthesis of soy oil based isothiocyanate is described. Allylicaly brominated soybean oil (ABSO) was reacted first with ammonium thiocyanate in tetrahydro furan to form allylic thiocyanates. These compounds were then converted to isothiocyanated soybean oil (ITSO) by a thermal rearrangement. Conversion was found to be 70%. The structure of the ITSO was characterized by IR and 1 H‐NMR techniques. Then ITSO was reacted with ethylene glycol, glycerol, and castor oil to produce polythiourethanes and ethylene diamine and triethylene tetra amine to produce polythioureas. Thermal properties of the products were determined by DSC and TGA techniques. DSC traces showed Tg's for ethylene glycol polythiourethane at −39 and 58°C, for glycerol polythiourethane at −39 and 126°C, for castor oil polythiourethane at −38°C and −17°C, for ethylene diamine polythiourea at −45°C, and for triethylene tetra amine poly thiourea at −39°C. Additionally, DSC analysis of polythioureas showed an endotherm at around 100°C. All of the polymers started to decompose around 200°C. Tensile properties of the polymers were determined. Polythiourethanes showed higher tensile strength and lower elongation when compared with their urea analogs. Stress at break values of the polymers were 1.2 MPa for glycerol polythiourethane, 0.6 MPa for ethylene glycol polythiourethane, 0.5 MPa for ethylene diamine polythiourea, and 0.9 MPa for triethylene tetra amine polythiourea polymers. Unfortunately, polymers synthesized showed poor solvent resistance. All polymers swelled and disintegrated in CH2Cl2 in 5 h. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Crack propagation behavior and toughness of V‐notched polyethylene terephthalate injection moldings
Authors: Ogazi‐Onyemaechi Bernard Chukwuemeka , Leong Yew Wei , Hamada Hiroyuki 
Published: November 2009

AbstractThe role of the skin and core regions in controlling the effects of V‐notches, on the fracture behavior of PET injection‐moldings, was correlated with their tensile and impact properties. Investigations revealed that there were three distinct fracture behaviors: ductile, semiductile, and brittle fracture transitions. The notch sensitivity factor for strength (KS) in the ductile and semiductile transitions indicates that the fracture strength was not sensitive to ≤1.5 mm deep notches, which is considered the skin region. The introduction of core‐deep notches (>1.5 mm) resulted in a rapid increase in KS. On the other hand, the notch sensitivity factor for energy (KT) shows that the fracture energy was not sensitive at ≤0.5 mm deep notches. However, KT increased drastically when notches >0.5 mm deep were introduced. The development of an anisotropic skin‐core structure in injection moldings is well acknowledged. This is revealed in a constant fracture behavior between 0.6 and 1.0 mm deep notches. Notably, there was a drastic change in the fracture pattern from ductile to semiductile at a critical 0.6 mm deep notch. The specimens experienced a mixed fracture behavior at 1.5 mm deep notch, which marks a transitional fracture pattern at the interface between the skin and core regions. Lastly, a constant fracture behavior was observed at notch depths ≥1.5 mm. Results show that crack opening, in the samples that had semiductile fracture, was a postnecking phenomenon. Before shear yielding, two shear lines that intersected at 45° were seen to originate from the crack root when a 1.2 kN load was applied. Conversely, crack opening and failure occurred simultaneously in brittle fractures. It is obvious that V‐notches provided a gradual transition in fracture behavior from the skin to the core regions, which confirms that the fracture behavior of PET injection moldings can be dependent on the skin and core structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Thermal pressure coefficient of a polyhedral oligomeric silsesquioxane (POSS)‐reinforced epoxy resin
Authors: Win K. Z. , Karim Taskin , Li Qingxiu , Simon Sindee L. , McKenna Gregory B. 
Published: November 2009

AbstractThe thermal pressure coefficients of a neat, unfilled, epoxy resin and a 10 wt % POSS (polyhedral oligomeric silsesquioxane)‐filled epoxy nanocomposite have been measured using a thick‐walled tube method. It is found that just below the glass transition temperature the thermal pressure coefficient is ∼ 20% smaller for the polymer composite containing 10% POSS than for the neat, unfilled resin. The thermal expansion coefficient and thermal pressure coefficient of the uncured POSS itself are also reported. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of ionic liquids and surfactants on zinc oxide nanoparticle activity in crosslinking of acrylonitrile butadiene elastomer
Authors: Przybyszewska Magdalena , Zaborski Marian 
Published: November 2009

AbstractThe goal of this work was to study the influence of several ionic liquids and cationic surfactants on zinc oxide nanoparticle activity in sulfur vulcanization of acrylonitrile butadiene elastomer (NBR). In this article, we discuss the effect of ionic liquids and surfactants on the cure characteristics, crosslink density, and distribution in the elastomer network as well as on mechanical properties of the acrylonitrile butadiene rubber. Ionic liquids (alkylimidazolium salts) and cationic surfactants (alkylammonium bromides) decrease the vulcanization time of rubber compounds. Their application results in the increase of vulcanizate crosslink density as well as of the heterogeneity of elastomer network. The influence of ionic liquids on the acrylonitrile butadiene elastomer properties depends on the anion present in the molecule and on the length of alkyl chains attached to the imidazolium ring. The most active ionic liquids seem to be the ones with the 1‐butyl‐3‐methylimidazolium cation or the BF4‐ anion. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synchrotron radiation circular dichroism of various G‐quadruplex structures
Authors: Holm Anne I. S. , Kohler Bern , Hoffmann Søren Vrønning , Brøndsted Nielsen Steen 
Published: November 2009

AbstractHere we report synchrotron radiation circular dichroism spectra of various G‐quadruplexes from 179 to 350 nm, and a number of bands in the vacuum ultraviolet (VUV) are reported for the first time. For a tetramolecular parallel structure, the strongest band in the spectrum is a negative band in the VUV at 182 nm; for a bimolecular antiparallel structure with diagonal loops, a new strong positive band is found at 190 nm; for a bimolecular parallel structure with edgewise loops, a strong positive band at 189 nm is observed; and for a self‐folded chair‐type structure, the strongest band in the spectrum is a positive band at 187 nm. For the tetramolecular parallel structure, the CD signals at all wavelengths are dominated by contributions from quartets of G bases, and the signal strength is approximately proportional to the number of quartets. Our experiments on well‐characterized G‐quadruplex structures lead us to question past attributions of CD signals to helix handedness and G quartet polarity. Although differences can be observed in the VUV region for the various quadruplex types, there do not appear to be clear‐cut spectral features that can be used to identify specific topological features. It is suggested that this is because a dominant positive band in the VUV seen near 190 nm in all quadruplex structures is due to intrastrand guanine–guanine base stacking. However, our spectra can serve as reference spectra for the G‐quadruplex structures investigated and, not least, to benchmark theoretical calculations and empirical models. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 429–433, 2010.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com