bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pre‐Columbian population dynamics in coastal southern Peru: A diachronic investigation of mtDNA patterns in the Palpa region by ancient DNA analysis
Authors: Fehren‐Schmitz Lars , Reindel Markus , Cagigao Elsa Tomasto , Hummel Susanne , Herrmann Bernd 
Published: July 2009

AbstractAlternative models have been proposed to explain the formation and decline of the south Peruvian Nasca culture, ranging from migration or invasion to autochthonous development and ecological crisis. To reveal to what extent population dynamic processes accounted for cultural development in the Nasca mainland, or were influenced by them, we analyzed ancient mitochondrial DNA of 218 individuals, originating from chronologically successive archaeological sites in the Palpa region, the Paracas Peninsula, and the Andean highlands in southern Peru. The sampling strategy allowed a diachronic analysis in a time frame from approximately 800 BC to 800 AD. Mitochondrial coding region polymorphisms were successfully analyzed and replicated for 130 individuals and control region sequences (np 16021–16408) for 104 individuals to determine Native American mitochondrial DNA haplogroups and haplotypes. The results were compared with ancient and contemporary Peruvian populations to reveal genetic relations of the archaeological samples. Frequency data and statistics show clear proximity of the Nasca populations to the populations of the preceding Paracas culture from Palpa and the Peninsula, and suggest, along with archaeological data, that the Nasca culture developed autochthonously in the Rio Grande drainage. Furthermore, the influence of changes in socioeconomic complexity in the Palpa area on the genetic diversity of the local population could be observed. In all, a strong genetic affinity between pre‐Columbian coastal populations from southern Peru could be determined, together with a significant differentiation from ancient highland and all present‐day Peruvian reference populations, best shown in the differential distribution of mitochondrial haplogroups. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.
Development of low‐biofouling polypropylene feedspacers for reverse osmosis
Authors: Hausman Richard , Gullinkala Tilak , Escobar Isabel C. 
Published: July 2009

AbstractMicrobial fouling, or biofouling, is the accumulation of microorganisms onto material surfaces. The goal of this project was to develop low‐biofouling polypropylene (PP) films through the functionalization of PP by a spacer arm with metal chelating ligands charged with copper ions. Virgin and modified PP films were put in contact with 3.0 ×105
Escherichia coli cells/mL solutions for periods of time varying from 24 to 168 h. Fourier transform infrared spectroscopy (FTIR) and x‐ray energy dispersive spectroscopy (EDS) were used to verify the functionalization reactions and monitor copper leaching. Direct counts of cells stained with dsDNA showed, invariably, that the microbial attachment to the modified PP films was an order of magnitune lower than on the virgin PP. Further, over a period of time of 2 weeks, no significant amounts of copper leached from the low‐biofouling PP films. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Highly concentrated cationic flocculants based on 80/20 wt % [2‐(acryloyloxy)ethyl]trimethylammonium chloride/acrylamide in an inverse microemulsion: Influence of the copolymerization variables on the flocculation performance
Authors: Ochoa‐Gómez José R. , Nieto‐Mestre J. , Escudero‐Sanz Francisco J. , Sasia P. M. , Río F. , Torrecilla‐Soria J. , Katime Issa A. 
Published: July 2009

AbstractThe influence of the total comonomer concentration (TCC; 30–42 wt %), emulsifier concentration (EC; 7.3–23 wt %), hydrophilic–lipophilic balance (HLB; 9–9.9), crosslinking agent (N,N′‐methylene bisacrylamide) concentration (CAC; 0–122.8 ppm with respect to TCC), and isopropyl alcohol (chain‐transfer agent) concentration (IPC; 0–1.5 wt % with respect to TCC) on the flocculation performance (FP) of 80/20 wt % acrylamide (AM)/[2‐(acryloyloxy)ethyl]trimethylammonium chloride (ADQUAT) copolymers obtained by semicontinuous inverse microemulsion copolymerization was studied with capillary suction time testing for FP assessment on anaerobic digested sludges. FP increased as TCC decreased, was nearly unaffected by EC, was maximum with an HLB of 9.5, decreased strongly with CAC, and showed a peak value with an IPC of 1 wt %. At a very high TCC, copolymer growth in a highly collapsed state resulted in greatly structured, high weight‐average molar mass flocculants with decreased swelling capacities (SCs), which did not favor bridging flocculation, and in increased shielding of their positive charges, which did not favor charge neutralization flocculation. However, industrially needed latices with both high TCC and good FP could be obtained by the addition of isopropyl alcohol, which, below a concentration of 1 wt %, improved FP by decreasing the weight‐average molar mass and thereby enhancing SC while maintaining long enough chains to be effective for bridging flocculation. On the basis of the results, new star‐shaped ADQUAT/AM copolymers are envisioned as flocculants with superior FP. A synthetic route is proposed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Perfume‐containing polyurea microcapsules with undetectable levels of free isocyanates
Authors: Jacquemond Marlène , Jeckelmann Nicolas , Ouali Lahoussine , Haefliger Olivier P. 
Published: July 2009

AbstractCore‐shell polyurea microcapsules with a 40% fragrance load were prepared by interfacial polymerization of guanidine and a technical polyisocyanate prepolymer containing mainly the biuret trimer derived from hexamethylene di‐isocyanate (HDI). Residual free polyisocyanates were still present at a level slightly above 100 mg NCO functional group per kg as determined by liquid chromatography hyphenated with tandem mass spectrometry of HDI and of its biuret trimer. This level was decreased by a factor of about 10 when the polymerization process was allowed to proceed for a longer time and by a factor of about 500 when guanidine or NaOH were added to the microcapsule suspension to act as scavengers. In these cases, polyisocyanate conversion was observed to proceed for about one month when the microcapsules were stored at room temperature before reaching a plateau at a level below 1 mg NCO/kg. Overall, ammonia was the most efficient polyisocyanate scavenger as no residual HDI biuret trimer and only less than 2 μg NCO/kg as HDI were detected at the end of the process, a level which had dropped below the limit of detection of 0.25 μg NCO/kg after about 40 days of aging at room temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Poly(hydroxybutyrate‐co‐hydroxyvalerate)/titanium dioxide nanocomposites: A degradation study
Authors: Buzarovska Aleksandra , Grozdanov Anita , Avella M. , Gentile G. , Errico M. 
Published: July 2009

AbstractNanocomposites, based on a poly(hydroxybutyrate‐co‐hydroxyvalerate) (PHBV) matrix and titanium dioxide (TiO2) nanoparticles and fabricated with a solvent‐casting technique, were characterized with differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. The content of TiO2 nanoparticles varied between 0.5 and 10 wt %. Degradation studies, including hydrolytic degradation in a strong base medium (1N NaOH) and degradation under ultraviolet light at 365 nm, were performed. It was confirmed that the inorganic filler had no great influence on thermal properties such as the melting and crystallization temperatures. Improved degradation temperatures were also confirmed with the increase in the filler content. Degradation observations confirmed significant increases in hydrolytic erosion with the filler content increasing in comparison with the degradation of a pure PHBV film. Also, the photocatalytic activity of the inorganic filler TiO2 in all investigated composites [irradiated at λ = 365 nm and immersed in a liquid medium (H2O)] was evaluated. The degraded samples were analyzed with Fourier transform infrared spectroscopy, which confirmed their increased crystallinity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of the molecular weight of poly(ether imide) on the viscoelastic phase separation of poly(ether imide)/epoxy blends
Authors: Gan Wenjun , Xiong Wei , Yu Yingfeng , Li Shanjun 
Published: July 2009

AbstractThe phase separation of diglycidyl ether of bisphenol A/methyl tetrahydrophthalic anhydride blends modified with three poly(ether imide)s (PEIs) of different molecular weights was investigated with scanning electron microscopy (SEM) and time‐resolved light scattering (TRLS). The morphologies observed by SEM for the three blends were all close to a cocontinuous structure with different periodic distances. The results of TRLS indicated that the phase separation for the PEI‐modified epoxy blends took place according to the spinodal decomposition mechanism and the onset time of phase separation, with the periodicity of the phase structure depending on the PEI molecular weight and cure temperature. The time‐dependent peak scattering vector was simulated with a Maxwell‐type viscoelastic relaxation equation, indicating that the coarsening process of epoxy droplets was mainly controlled by the viscoelastic flow. Relaxation times obtained at different temperatures for the three blends could be described by the Williams–Landel–Ferry equation. The effects of the PEI molecular weight on the processes of viscoelastic phase separation were investigated, and the observed trends could be explained qualitatively through thermodynamic analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
An interactive method for teaching anatomy of the human eye for medical students in ophthalmology clinical rotations
Authors: Kivell Tracy L. , Doyle Sara K. , Madden Richard H. , Mitchell Terry L. , Sims Ershela L. 
Published: July 2009

AbstractMuch research has shown the benefits of additional anatomical learning and dissection beyond the first year of medical school human gross anatomy, all the way through postgraduate medical training. We have developed an interactive method for teaching eye and orbit anatomy to medical students in their ophthalmology rotation at Duke University School of Medicine. We provide review lectures on the detailed anatomy of the adult human eye and orbit as well as the developmental anatomy of the eye. These lectures are followed by a demonstration of the anatomy of the orbit using conventional frontal and superior exposures on a prosected human cadaver. The anatomy is projected onto a large LCD screen using a mounted overhead camera. Following a brief lecture on clinically relevant anatomy, each student then dissects a fresh porcine (pig) eye under low magnification using a dissecting microscope. These dissections serve to identify structures extrinsic to the eyeball, including extraocular muscle attachments, small vessels, optic nerve stalk, and fascial sheath of the eyeball (Tenon's fascia). Dissection then shifts to the internal anatomy of the eyeball. The size and anatomy of the porcine eye is comparable with that of the human and the dissection provides students with a valuable hands‐on learning opportunity that is otherwise not available in embalmed human cadavers. Students and clinical faculty feedback reveal high levels of satisfaction with the presentation of anatomy and its scheduling early during the ophthalmology clerkship. Anat Sci Educ 2:173–178, 2009. © 2009 American Association of Anatomists.
Undergraduate virology exercises demonstrate conventional and real‐time PCR using commercially available HIV primers and noninfectious target
Authors: Sulzinski Michael A. , Wasilewski Melissa A. , Farrell James C. , Glick David L. 
Published: July 2009

AbstractIt is an extraordinary challenge to offer an undergraduate laboratory course in virology that teaches hands‐on, relevant molecular biology techniques using nonpathogenic models of human virus detection. To our knowledge, there exists no inexpensive kits or reagent sets that are appropriate for demonstrating real‐time PCR (RT‐PCR) in an undergraduate laboratory course in virology. Here we describe simple procedures for student exercises that demonstrate the PCR detection of an HIV target nucleic acid. Our procedures combine a commercially available kit for conventional PCR with a modification for RT‐PCR using the same reagents in the kit, making it possible for an instructor with access to a LightCycler® instrument to implement a relevant student exercise on RT‐PCR detection of HIV nucleic acid targets. This combination of techniques is useful for demonstrating and comparing conventional PCR amplification and detection with agarose gel electrophoresis, with real‐time PCR over a series of three laboratory periods. The series of laboratory periods also is used to provide the foundation for teaching the concept of PCR primer design, optimization of PCR detection systems, and introduction to nucleic acid queries using NCBI‐BLAST to find and identify primers, amplicons, and other potential amplification targets within the HIV viral genome. The techniques were successfully implemented at the Biology 364 undergraduate virology course at the University of Scranton during the Fall 2008 semester. The techniques are particularly targeted to students who intend to pursue either postgraduate technical employment or graduate studies in the molecular life sciences.
A simple test tube‐based ELISA experiment for the high‐school classroom
Authors: Brokaw Ann , Cobb Brian A. 
Published: July 2009

AbstractImmunology is gaining prominence both in the media as well as on the Advanced Placement (AP) exam in Biology. One of the challenges of teaching modern biological topics such as immunology and biochemistry in the high‐school setting is the increased reliance on expensive technology in the research world. To begin to bridge this widening gap, we devised an experiment using a novel macroscale enzyme‐linked immunosorbent assay that is suitable for AP‐level high‐school biology classrooms as well as entry‐level collegiate laboratories. This novel method does not require a plate reader for data analysis, but instead relies on more common and inexpensive equipment such as a clinical test tube centrifuge and a simple test tube spectrophotometer. The experimental plan focuses on students measuring antibody concentrations in “unknown” samples and includes the collection and analysis of a standard curve using reagents prepared by the instructor. Students will be introduced to enzyme action, quantitative laboratory technique, antibodies, and the immune system, with the overall goal being to explore and highlight the inherent connections within the fields of biochemistry and immunology.
A single nutrient feed supports both chemically defined NS0 and CHO fed‐batch processes: Improved productivity and lactate metabolism
Authors: Ma Ningning , Ellet JoAnn , Okediadi Centy , Hermes Paul , McCormick Ellen , Casnocha Susan 
Published: July 2009

AbstractA chemically defined nutrient feed (CDF) coupled with basal medium preloading was developed to replace a hydrolysate‐containing feed (HCF) for a fed‐batch NS0 process. The CDF not only enabled a completely chemically defined process but also increased recombinant monoclonal antibody titer by 115%. Subsequent tests of CDF in a CHO process indicated that it could also replace the hydrolysate‐containing nutrient feed in this expression system as well as providing an 80% increase in product titer. In both CDF NS0 and CHO processes, the peak lactate concentrations were lower and, more interestingly, lactate metabolism shifted markedly from net production to net consumption when cells transitioned from exponential to stationary growth phase. Subsequent investigations of the lactate metabolic shift in the CHO CDF process were carried out to identify the cause(s) of the metabolic shift. These investigations revealed several metabolic features of the CHO cell line that we studied. First, glucose consumption and lactate consumption are strictly complementary to each other. The combined cell specific glucose and lactate consumption rate was a constant across exponential and stationary growth phases. Second, Lactate dehydrogenase (LDH) activity fluctuated during the fed‐batch process. LDH activity was at the lowest when lactate concentration started to decrease. Third, a steep cross plasma membrane glucose gradient exists. Intracellular glucose concentration was more than two orders of magnitude lower than that in the medium. Fourth, a large quantity of citrate was diverted out of mitochondria to the medium, suggesting a partially truncated tricarboxylic acid (TCA) cycle in CHO cells. Finally, other intermediates in or linked to the glycolytic pathway and the TCA cycle, which include alanine, citrate, isocitrate, and succinate, demonstrated a metabolic shift similar to that of lactate. Interestingly, all these metabolites are either in or linked to the pathway downstream of pyruvate, but upstream of fumarate in glucose metabolism. Although the specific mechanisms for the metabolic shift of lactate and other metabolites remain to be elucidated, the increased understanding of the metabolism of CHO cultures could lead to future improvements in medium and process development. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Development of a high throughput protein a well‐plate purification method for monoclonal antibodies
Authors: Hopp Jennifer , Pritchett Ross , Darlucio Maria , Ma Junfen , Chou Judy H. 
Published: July 2009

AbstractWe have developed a new high throughput method for the purification of monoclonal antibodies from harvested cell culture fluid for analytical characterization. This method uses Protein A resin in a 96 well‐plate format with protein loading sufficient to perform multiple analyses per well. Resin and buffer conditions were optimized to obtain aggregate and charge variant comparability with three preparative Protein A purified monoclonal antibodies. We are able to successfully demonstrate comparability for aggregate within 0.25% based upon size‐exclusion chromatography. Acidic species were found to be within 2% from the preparative purified control based upon cation‐exchange chromatography, 5% based upon capillary zone electrophoresis, and 3% based upon imaged capillary isoelectric focusing. Glycan distribution was analyzed and was within 1% of the preparative purified controls. A tryptic digest was performed and all peaks in the preparative purified control were found in the first elution from the well‐plate format. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Parallel gene cloning and protein production in multiple expression systems
Authors: Wang Hui‐Min , Shih Yan‐Ping , Hu Su‐Ming , Lo Wen‐Tsung , Lin Hui‐Min , Ding Shih‐Shiu , Liao Hsin‐Chi , Liang Po‐Huang 
Published: July 2009

AbstractTo quickly find an optimal expression system for recombinant protein production, a set of vectors with the same restriction sites were constructed for parallel cloning of a target gene and recombinant protein production in prokaryotic and eukaryotic expression systems, simultaneously. These vectors include nucleotide sequences encoding protein tags and protease recognition sites for tag removal, followed by the cloning sites 5′‐EcoRI/3′‐XhoI identical in these vectors for ligating with the sticky‐end PCR product of a target gene. Our vectors allow parallel gene cloning and protein production in multiple expression systems with minimal cloning effort. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
A radiologic and histologic study of the os peroneum: Prevalence, morphology, and relationship to degenerative joint disease of the foot and ankle in a cadaveric sample
Authors: Muehleman C. , Williams J. , Bareither M.L. 
Published: July 2009

AbstractThe present study investigated the prevalence of an os peroneum (OP, a sesamoid bone) in a cadaveric sample and its relationship to the shape of the cuboid tuberosity, and cartilage degeneration at the cuboid tuberosity and in regional joints within the foot (first metatarsophalangeal and calcaneocuboid) and ankle. The fibularis longus tendon of 33 embalmed human cadavers (mean age 81 years) were obtained from the anatomy laboratory. Nineteen of 64 tendons (30%) displayed an OP both radiographically and histologically. The os peronei ranged in size from small spicules to prominent masses: mean area 2.48 mm2 (left) and 2.70 mm2 (right). Histologically, the os peronei were cancellous bone, the largest occupying most of the tendon at the point of contact with the cuboid tuberosity. Fibrocartilage was present at their borders, merging with dense regular fibrous tissue and peritenon. The talocrural, calcaneocuboid, and first metatarsophalangeal joints were examined for cartilage integrity and osteophytes based on an earlier suggestion that there may be an association between degenerative joint disease and endochondral bone formation. There was no statistical correlation between presence of an OP with any of the following parameters: age, gender, body size, cartilage degeneration, or osteophytes within any of the joints examined. Therefore, the presence of an OP does not appear to be associated with increased endochondral ossification or degenerative joint disease. This study does not preclude the possibility that sesamoid bone formation may be associated with biomechanical functions within the foot; thus, future studies may be warranted. Clin. Anat. 22:747–754, 2009. © 2009 Wiley‐Liss, Inc.
Novel insights into the elastic and muscular components of the human trachea
Authors: Kamel Kirollos Salah , Beckert Lutz E. , Stringer Mark D. 
Published: July 2009

AbstractDespite its probable importance in health and disease, the elastic tissue in the trachea has rarely been investigated. In addition, various aspects of the trachealis muscle are controversial. The aim of this study was to clarify this clinically relevant anatomy. Ten cadaveric tracheobronchial specimens (age range 68–101 years; seven males; no major airway pathology) were qualitatively investigated by microdissection. Serial histologic sections from multiple sites in three specimens were analyzed after staining for elastin. Findings were correlated with observations from video tracheobronchoscopies. An extensive and prominent meshwork of elastic tissue was found within the trachea and bronchi. Elastic fibers were predominantly longitudinal and aggregated into discrete bundles within the membranous wall of the trachea and main bronchi; a discrete fibroelastic membrane bridging the membranous wall of the trachea; and vertical laminae connecting the ends of successive cartilages. The longitudinal elastic bundles continued into the segmental bronchi, becoming thinner and more circumferentially distributed. Trachealis consisted of a transverse layer of smooth muscle deep to the fibroelastic membrane of the membranous wall of the trachea, together with scattered longitudinal muscle bundles, mostly embedded within the fibroelastic membrane in the distal half of the trachea. In conclusion, there is an extensive but relatively neglected elastic framework within the tracheobronchial tree. This is likely to have major clinical relevance to the pathophysiology of respiratory disease and ageing. The trachealis muscle is more complex than previously stated. Clin. Anat. 22:689–697, 2009. © 2009 Wiley‐Liss, Inc.