bluuebunny/crossref_metadata_2025 huggingface dataset:
Noncore RAG1 Regions Promote Vβ Rearrangements and αβ T Cell Development by Overcoming Inherent Inefficiency of Vβ Recombination Signal Sequences
Authors: Horowitz Julie E. , Bassing Craig H.
Published: January 2014

The RAG proteins are comprised of core endonuclease domains and noncore regions that modulate endonuclease activity. Mutation or deletion of noncore RAG regions in humans causes immunodeficiency and altered TCR repertoire, and mice expressing core but not full-length Rag1 (Rag1C/C) or Rag2 (Rag2C/C) exhibit lymphopenia, reflecting impaired V(D)J recombination and lymphocyte development. Rag1C/C mice display reduced D-to-J and V-to-DJ rearrangements of TCRβ and IgH loci, whereas Rag2C/C mice show decreased V-to-DJ rearrangements and altered Vβ/VH repertoire. Because Vβs/VHs only recombine to DJ complexes, the Rag1C/C phenotype could reflect roles for noncore RAG1 regions in promoting recombination during only the D-to-J step or during both steps. In this study, we demonstrate that a preassembled TCRβ gene, but not a preassembled DβJβ complex or the prosurvival BCL2 protein, completely rescues αβ T cell development in Rag1C/C mice. We find that Rag1C/C mice exhibit altered Vβ utilization in Vβ-to-DJβ rearrangements, increased usage of 3′Jα gene segments in Vα-to-Jα rearrangements, and abnormal changes in Vβ repertoire during αβ TCR selection. Inefficient Vβ/VH recombination signal sequences (RSSs) have been hypothesized to cause impaired V-to-DJ recombination on the background of a defective recombinase as in core-Rag mice. We show that replacement of the Vβ14 RSS with a more efficient RSS increases Vβ14 recombination and rescues αβ T cell development in Rag1C/C mice. Our data indicate that noncore RAG1 regions establish a diverse TCR repertoire by overcoming Vβ RSS inefficiency to promote Vβ recombination and αβ T cell development, and by modulating TCRβ and TCRα gene segment utilization.
Posttranscriptional Modulation of Cytokine Production in T Cells for the Regulation of Excessive Inflammation by TFL
Authors: Minagawa Kentaro , Wakahashi Kanako , Kawano Hiroki , Nishikawa Shinichiro , Fukui Chie , Kawano Yuko , Asada Noboru , Sato Mari , Sada Akiko , Katayama Yoshio , Matsui Toshimitsu
Published: January 2014

Posttranscriptional machinery regulates inflammation and is associated with autoimmunity as well as tumorigenesis in collaboration with transcription factors. We previously identified the tumor suppressor gene transformed follicular lymphoma (TFL) on 6q25 in a patient with follicular lymphoma, which transformed into diffuse large B cell lymphoma. TFL families have a common RNase domain that governs macrophage-mediated inflammation. In human peripheral blood, TFL is dominantly expressed at the glycine- and tryptophan-rich cytoplasmic processing bodies of T lymphocytes, and it is persistently upregulated in activated T cells. To address its physiological role, we established TFL−/− mice in which TFL−/− lymphocytes proliferated more rapidly than TFL+/+ upon stimulation with inappropriate cytokine secretion, including IL-2, IL-6, and IL-10. Moreover, TFL inhibited the synthesis of cytokines such as IL-2, IL-6, IL-10, TNF-α, and IL-17a by 3′ untranslated region RNA degradation. Experimental autoimmune encephalitis induced in TFL−/− mice demonstrated persistent severe paralysis. CNS-infiltrated CD4+ T cells in TFL−/− mice contained a higher proportion of Th17 cells than did those in TFL+/+ mice during the resolution phase, and IL-17a mRNA levels were markedly increased in TFL−/− cells. These results suggest that TFL may play an important role in attenuating local inflammation by suppressing the infiltration of Th17 cells in the CNS during the resolution phase of experimental autoimmune encephalitis. TFL is a novel gradual and persistent posttranscriptional regulator, and the TFL-driven attenuation of excessive inflammation could contribute to recovery from T cell–mediated autoimmune diseases.
Enforced Expression of Gata3 in T Cells and Group 2 Innate Lymphoid Cells Increases Susceptibility to Allergic Airway Inflammation in Mice
Authors: KleinJan Alex , Klein Wolterink Roel G. J. , Levani Yelvi , de Bruijn Marjolein J. W. , Hoogsteden Henk C. , van Nimwegen Menno , Hendriks Rudi W.
Published: January 2014

Airway inflammation in allergic asthma reflects a threshold response of the innate immune system, including group 2 innate lymphoid cells (ILC2), followed by an adaptive Th2 cell–mediated response. Transcription factor Gata3 is essential for differentiation of both Th2 cells and ILC2. We investigated the effects of enforced Gata3 expression in T cells and ILC2 on the susceptibility of mice to allergic airway inflammation (AAI). We used CD2-Gata3 transgenic (Tg) mice with enforced Gata3 expression driven by the CD2 promoter, which is active both in T cells and during ILC2 development. CD2-Gata3 Tg mice and wild-type (WT) littermates were analyzed in mild models of AAI without adjuvants. Whereas OVA allergen exposure did not induce inflammation in WT controls, CD2-Gata3 Tg mice showed clear AAI and enhanced levels of IL-5 and IL-13 in bronchoalveolar lavage. Likewise, in house dust mite–driven asthma, CD2-Gata3 Tg mice were significantly more susceptible to AAI than WT littermates, whereby both ILC2 and Th2 cells were important cellular sources of IL-5 and IL-13 in bronchoalveolar lavage and lung tissue. Compared with WT littermates, CD2-Gata3 Tg mice contained increased numbers of ILC2, which expressed high levels of IL-33R and contributed significantly to early production of IL-4, IL-5, and IL-13. CD2-Gata3 Tg mice also had a unique population of IL-33–responsive non-B/non-T lymphoid cells expressing IFN-γ. Enforced Gata3 expression is therefore sufficient to enhance Th2 and ILC2 activity, and leads to increased susceptibility to AAI after mild exposure to inhaled harmless Ags that otherwise induce Ag tolerance.
Fetal Intervention Increases Maternal T Cell Awareness of the Foreign Conceptus and Can Lead to Immune-Mediated Fetal Demise
Authors: Wegorzewska Marta , Nijagal Amar , Wong Charissa M. , Le Tom , Lescano Ninnia , Tang Qizhi , MacKenzie Tippi C.
Published: January 2014

Fetal interventions to diagnose and treat congenital anomalies are growing in popularity but often lead to preterm labor. The possible contribution of the maternal adaptive immune system to postsurgical pregnancy complications has not been explored. We recently showed that fetal intervention in mice increases maternal T cell trafficking into the fetus and hypothesized that this process also may lead to increased maternal T cell recognition of the foreign conceptus and subsequent breakdown in maternal–fetal tolerance. In this study, we show that fetal intervention in mice results in accumulation of maternal T cells in the uterus and that these activated cells can produce effector cytokines. In adoptive transfer experiments, maternal T cells specific for a fetal alloantigen proliferate after fetal intervention, escape apoptosis, and become enriched compared with endogenous T cells in the uterus and uterine-draining lymph nodes. Finally, we demonstrate that such activation and accumulation can have a functional consequence: in utero transplantation of hematopoietic cells carrying the fetal alloantigen leads to enhanced demise of semiallogeneic fetuses within a litter. We further show that maternal T cells are necessary for this phenomenon. These results suggest that fetal intervention enhances maternal T cell recognition of the fetus and that T cell activation may be a culprit in postsurgical pregnancy complications. Our results have clinical implications for understanding and preventing complications associated with fetal surgery such as preterm labor.
Resident Duty Hours in the Outpatient Electronic Health Record Era: Inaccuracies and Implications
Authors: Gilleland Meghan , Komis Katherine , Chawla Sonya , Fernandez Stephen , Fishman Mary , Adams Michael
Published: January 2014

Background

The Accreditation Council for Graduate Medical Education expects resident duty hours to be monitored, yet no previous studies have examined the effect of after-hours electronic health record (EHR) use on resident hours or burnout.

Objective

We assessed internal medicine residents' perceived and actual time spent on after-hours outpatient EHR use and calculated increased duty hours if after-hours EHR use were included; we also assessed its effect on resident burnout.

Methods

We retrospectively aggregated time spent logged on to the outpatient EHR for residents in a general internal medicine clinic for 13 weeks in 2011. Residents completed a survey on EHR use, which was correlated with objectively recorded data on EHR usage. We compared actual and self-reported EHR time and identified violations that would be generated if these hours were included in reported duty hours. We also correlated resident after-hours EHR use with responses to an internally developed burnout survey.

Results

The 44 residents in this study overestimated time spent on the ambulatory EHR (they spent 3.03 hours/week on after-hours use compared with a recorded 1.20 hours/week). In total, 190 duty hour violations (mean duration of violation  =  37 minutes) would have been generated if after-hours EHR usage were included in residents' reported duty hours.

Conclusions

Resident estimates of EHR use by residents were not accurate; including after-hours EHR use would increase the number of reported duty hour violations. There was no association between after-hours EHR use and resident burnout.
Performance of Residents Serving as Clinical Teachers: A Student-Based Assessment
Authors: Owolabi Mayowa O. , Afolabi Adefemi O. , Omigbodun Akinyinka O.
Published: January 2014

Background

Little is known about the competences of residents as clinical teachers in African health care institutions.

Objective

We evaluated the clinical teaching skills of internal medicine residents from the perspective of medical students in a tertiary teaching institution in Africa.

Methods

We used the augmented Stanford Faculty Development Program Questionnaire, which has evidence of validity and reliability. To avoid a Hawthorne effect, students completed the questionnaire anonymously and confidentially after clinical teaching sessions by residents. A minimum score of 4 on a scale of 1 to 5 was defined a priori as possession of good clinical teaching skills.

Results

Sixty-four medical students assessed all 20 internal medicine residents in the Department of Medicine, University of Ibadan. Mean performance scores for the domains ranged from 3.07 to 3.66. Residents performed best in creating a good learning climate and worst in the promotion of understanding and retention. Sex of the resident, duration of residency, and rank had no significant impact (.09 < P < .94) on their teaching skills.

Conclusions

Consistent with other observations in the literature, residents' clinical teaching skills were suboptimal, particularly in their ability to promote understanding and retention. To enhance these skills, we recommend the integration of appropriately tailored programs to teach pedagogic skills programs in residency training.
Death and Disability in a Younge Phase Community
Authors: Spence Michael W. , Williams Lana J. , Wheeler Sandra M.
Published: January 2014

Roffelsen is an early Younge phase mortuary component in southwestern Ontario. The single burial feature is a pit containing the articulated skeletons of seven successively buried individuals, ranging in age from a few months to late middle age. All had been stripped of soft tissues, except for the connecting tissues that maintained their articulation. Most also had a disk cut from the cranium and a hole drilled near bregma. All but the infant display various forms of developmental failure of the outer and middle ear and the petrous portion of the temporal bone. The pit was apparently the burial facility for an extended family with significant hearing impairments. This disability may have limited their interaction with neighboring communities, perhaps even playing a role in their eventual disappearance as a separate community.
Concerning the Atlatl and the Bow: Further Observations Regarding Arrow and Dart Points in the Archaeological Record
Authors: Walde Dale
Published: January 2014

Hildebrandt and King (2012) propose a new method for distinguishing between archaeologically obtained atlatl darts and arrow points, suggesting their dart-arrow index identifies specimens more accurately than previously developed multivariate approaches. They assert that use of their index supports conclusions that the bow was a superior technology and replaced the atlatl quickly. I use their index, as well as Shott’s (1997) equations, to analyze southern Saskatchewan archaeological point specimens. My results suggest that the proposed dart-arrow index performs poorly for Canadian Plains specimens and that atlatl and bow technology coexisted for an extended period of time.
Darts, Arrows, and Archaeologists: Distinguishing Dart and Arrow Points in the Archaeological Record
Authors: Erlandson Jon M. , Watts Jack L. , Jew Nicholas P.
Published: January 2014

Using several methods to distinguish dart and arrow points, archaeologists have suggested that the bow and arrow appeared in various parts of the world between ˜65,000 and 1,000 years ago. Hildebrandt and King (2012) proposed a dart-arrow index (DAI) to help differentiate dart and arrow points, rejecting claims that the bow and arrow was introduced to western North America prior to the Late Holocene. We used the DAI and other methods to evaluate ˜11,700-year-old projectile points from Santa Rosa Island, obtaining mean values below the threshold for darts, comparable to several North American arrow point types. We have no direct evidence that these small points were used on darts, arrows, or hand-thrown spears, but faunal associations suggest that they may have served as harpoon tips used on atlatl darts to capture birds, fish, and marine mammals. The DAI and other methods for discriminating between dart and arrow points are based almost exclusively on ethnographic and archaeological specimens from interior regions. Our analysis suggests that such methods should not be applied universally, especially in coastal or other aquatic settings, and that archaeologists should continue to critically assess the antiquity of the bow and arrow and the function of projectile points worldwide.
Pre-Clovis Lithic Technology at the Debra L. Friedkin Site, Texas: Comparisons to Clovis through Site-Level Behavior, Technological Trait-List, and Cladistic Analyses
Authors: Jennings Thomas A. , Waters Michael R.
Published: January 2014

Humans first left Siberia and colonized the Americas perhaps around 16,000 years ago, and the Clovis archaeological complex in North America has traditionally been linked to this migratory pulse. Archaeologists searching for evidence of Clovis technological antecedents have focused their attention on the Beringian and Siberian archaeological records. Growing evidence for the pre-Clovis occupation of North America provides a possible alternative source for the origins of Clovis. In this paper, we present new data on the pre-Clovis lithic assemblage from the Debra L. Friedkin site, Texas, and compare Clovis and pre-Clovis lithic technological signatures. We show that while Clovis and pre-Clovis share some important technological traits, they also differ in important ways. We conclude that the pre-Clovis assemblage from Debra L. Friedkin cannot be called “Clovis,” but it could represent a technological antecedent of Clovis.
Eye of the Needle: Cold Stress, Clothing, and Sewing Technology During the Younger Dryas Cold Event in North America
Authors: Osbora Alan J.
Published: January 2014

This paper examines the possible underlying systemic contexts) for spurred flake gravers and eyed bone needles recovered from Paleoindian sites in North America. The idea that spurred flake gravers and eyed bone needles were closely associated is not new. Archaeologists in both Eurasia and North America have also proposed that eyed bone and ivory needles were used for manufacturing tailored skin clothing. It is suggested here that spurred flake gravers and eyed bone needles may, in fact, be the material correlates of critical non-subsistence related work carried out by women to meet the challenges of very severe winters and cold stress of the Younger Dryas Cold Event (YDCE) between 12,900–11,600 cal. B.P. It is argued here that such expediently produced flake implements and curated sewing technology including eyed needles ultimately reflect the significant ecological bottlenecks) posed by the YDCE for Paleoindian populations. Metric attributes of both spurred flake gravers and eyed bone needles, their spatial co-occurrence in archaeological contexts, and their temporal co-occurrence within the YDCE lend empirical support for this causal argument.
Grand Challenges for Archaeology
Authors: Kintigh Keith W. , Altschul Jeffrey H. , Beaudry Mary C. , Drennan Robert D. , Kinzig Ann P. , Kohler Timothy A. , Limp W. Fredrick , Maschner Herbert D. G. , Michener William K. , Pauketat Timothy R. , Peregrine Peter , Sabloff Jeremy A. , Wilkinson Tony J. , Wright Henry T. , Zeder Melinda A.
Published: January 2014

This article represents a systematic effort to answer the question, What are archaeology’s most important scientific challenges? Starting with a crowd-sourced query directed broadly to the professional community of archaeologists, the authors augmented, prioritized, and refined the responses during a two-day workshop focused specifically on this question. The resulting 25 “grand challenges” focus on dynamic cultural processes and the operation of coupled human and natural systems. We organize these challenges into five topics: (1) emergence, communities, and complexity; (2) resilience, persistence, transformation, and collapse; (3) movement, mobility, and migration; (4) cognition, behavior, and identity; and (5) human-environment interactions. A discussion and a brief list of references accompany each question. An important goal in identifying these challenges is to inform decisions on infrastructure investments for archaeology. Our premise is that the highest priority investments should enable us to address the most important questions. Addressing many of these challenges will require both sophisticated modeling and large-scale synthetic research that are only now becoming possible. Although new archaeological fieldwork will be essential, the greatest pay off will derive from investments that provide sophisticated research access to the explosion in systematically collected archaeological data that has occurred over the last several decades.
Evaluating Cahokian Contact and Mississippian Identity Politics in the Late Prehistoric Central Illinois River Valley
Authors: Bardolph Dana N.
Published: January 2014

This paper employs a practice-based framework for investigating early Mississippian period culture contact and identity negotiation in the Central Illinois River Valley (CIRV) through the lens offoodways. The Evelandphase (A.D. 1100–1200) was a setting of significant cultural change as a result of the movement of Cahokian people, objects, and ideas into the region. Recent analysis of excavated materials from the Lamb site in the southern portion of the CIRV affords a closer look at this historical process. Using ceramic and pit feature data, I assess Cahokian influence on traditional Late Woodlandera culinary practices. I conclude that although local residents were actively adopting some aspects of Mississippian culture (including Cahokia potting traditions), they retained traditional Late Woodland organizational practices of cooking, serving, and storing food. By placing the organization offoodways at the center of this study, this paper illuminates another dimension of Cahokian contact in the region.
Ritual Change and the Distant: Mesoamerican Iconography, Scarlet Macaws, and Great Kivas in the Mimbres Region of Southwestern New Mexico
Authors: Gilman Patricia A. , Thompson Marc , Wyckoff Kristina C.
Published: January 2014

The Mimbres Classic period (A .D. 1000–1130) in southwestern New Mexico was marked by dramatic and complex changes. The use of Great Kivas ended, and macaws and Mesoamerican-inspired iconography appeared. We argue that these events were systematically related and signify observable changes in Mimbres ritual economy. The presence of macaws, images of macaws, and representations of characters and motifs from the Hero Twins saga suggest that ideology accompanied macaws north from the Gulf Coast of Mexico. We recognize and discuss episodes and icons from the saga painted on Mimbres black-on-white bowls and propose that the macaws and narrative reached the Mimbres region through direct acquisition rather than down-the-line trade. This research has significant implications for the importance of long distance travel to faraway places and interaction with distant peoples, Mesoamerican-southwestern United States relationships, changing religious practices in non-hierarchical societies, and the adoption of extrinsic elements into local settings.
Les professionnels de la surveillance financière. Le malentendu comme condition de possibilité1
Authors: Amicelle2 Anthony
Published: January 2014

Le suivi de la piste financière fait aujourd’hui partie des pratiques instituées en matière de police et de renseignement. Située à l’interface de la finance et de la sécurité, la lutte contre le blanchiment de capitaux et le financement du terrorisme repose sur les relations de coopération tissées entre deux groupes d’acteurs aux motivations et aux savoir-faire différents. La notion floue d’« argent sale » est en effet le point de rencontre d’une constellation d’intérêts et de deux logiques d’action propres aux forces de l’ordre et aux opérateurs du système financier. Analysant le dispositif anti-blanchiment au Royaume-Uni, le présent article met en lumière l’articulation fragile de ces deux logiques d’action autour d’un malentendu sur le sens donné à la lutte contre l’« argent sale ». Loin de constituer un obstacle à l’élaboration et à l’opérationnalisation d’une politique spécifique, le malentendu est ici sa condition même de possibilité. Méprises et divergences d’interprétation sur le « problème » à traiter et les objectifs à poursuivre contribuent paradoxalement à la formation du bataillon bigarré des professionnels de la surveillance financière.
Equatorial signatures of the Pacific Meridional Modes: Dependence on mean climate state
Authors: Zhang Honghai , Deser Clara , Clement Amy , Tomas Robert
Published: January 2014

Extratropical atmospheric variability can impact tropical climate in the Pacific sector via the Pacific Meridional Modes (PMMs). The South PMM (SPMM) has a larger equatorial signature than the North PMM (NPMM) for the same amount of extratropical variability. Here we explain this interhemispheric asymmetry using an atmospheric general circulation model coupled to a slab ocean model. By imposing an anomalous interhemispheric heating gradient, we strengthen the northeasterly trades and weaken the southeasterly trades, shifting the Intertropical Convergence Zone south of the equator. As a result, the SPMM no longer influences the equatorial region while the NPMM shows strengthened linkages to the central‐western equatorial Pacific. By demonstrating that background winds determine the propagation of the wind‐evaporation‐sea surface temperature feedback fundamental for the PMMs, we conclude that the interhemispheric asymmetry between the PMMs is largely attributed to the asymmetric mean trades in the Pacific. The results have implications for both paleoclimate studies and model development.
Predictions of barrier island berm evolution in a time‐varying storm climatology
Authors: Plant Nathaniel G. , Flocks James , Stockdon Hilary F. , Long Joseph W. , Guy Kristy , Thompson David M. , Cormier Jamie M. , Smith Christopher G. , Miselis Jennifer L. , Dalyander P. Soupy
Published: January 2014

Low‐lying barrier islands are ubiquitous features of the world's coastlines, and the processes responsible for their formation, maintenance, and destruction are related to the evolution of smaller, superimposed features including sand dunes, beach berms, and sandbars. The barrier island and its superimposed features interact with oceanographic forces (e.g., overwash) and exchange sediment with each other and other parts of the barrier island system. These interactions are modulated by changes in storminess. An opportunity to study these interactions resulted from the placement and subsequent evolution of a 2 m high sand berm constructed along the northern Chandeleur Islands, LA. We show that observed berm length evolution is well predicted by a model that was fit to the observations by estimating two parameters describing the rate of berm length change. The model evaluates the probability and duration of berm overwash to predict episodic berm erosion. A constant berm length change rate is also predicted that persists even when there is no overwash. The analysis is extended to a 16 year time series that includes both intraannual and interannual variability of overwash events. This analysis predicts that as many as 10 or as few as 1 day of overwash conditions would be expected each year. And an increase in berm elevation from 2 m to 3.5 m above mean sea level would reduce the expected frequency of overwash events from 4 to just 0.5 event‐days per year. This approach can be applied to understanding barrier island and berm evolution at other locations using past and future storm climatologies.
Controlling the Optical, Electrical and Chemical Properties of Carbon Inverse Opal by Nitrogen Doping
Authors: Morelos‐Gómez Aarón , Mani‐González Pierre G. , Aliev Ali E. , Muñoz‐Sandoval Emilio , Herrera‐Gómez Alberto , Zakhidov Anvar A. , Terrones Humberto , Endo Morinobu , Terrones Mauricio
Published: January 2014

Nitrogen‐doped carbon inverse opal (CIO‐N) is synthesized by a two‐step process involving the infiltration of carbon‐nitrogen precursors within opals followed by the thermolysis and removal of the opal structure in hydrofluoric acid (HF). Undoped samples exhibit a reflection peak in the red region of the spectrum whereas N‐doped samples display shifts to the blue region of the spectrum as the nitrogen content is increased. The degree of crystallinity of CIO‐N strongly depends upon the nitrogen content and on the size of the precursor silica particles used to prepare the inverted opals. In addition, the introduction of nitrogen into the samples is able to increase the electrical conductivity by one order of magnitude from 2 to 30 S cm‐1 (at room temperature). All samples are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), ultraviolet‐visible (UV‐Vis) spectroscopy, and electrical conductivity measurements. It is envisaged that CIO‐N could have important applications in the fabrication of photonic crystals, photoconducting materials, molecular sensors, field emission devices, capacitors, batteries, among many others.
Core/Shell and Hollow Ultra High Molecular Weight Polyethylene Nanofibers and Nanoporous Polyethylene Prepared by Mesoscopic Shape Replication Catalysis
Authors: Müller Georg F. J. , Stürzel Markus , Mülhaupt Rolf
Published: January 2014

Polyvinyl alcohol (PVA) nanofibers, produced by electrospinning, represent attractive high‐surface‐area supports for olefin polymerization catalysts. Tethered with metal alkyls, PVA nanofibers immobilize a great variety of transition metal compounds, thus producing highly active nanofiber‐supported Ziegler‐, metallocene‐, and post‐metallocene catalysts. Whereas most conventional heterogeneous polymerization catalysts form particles, PVA‐nanofiber‐supported catalysts enable polyolefin nanofiber and nanostructure formation by mesoscopic shape replication using electrospun nanofibers as templates. At low ethylene pressure, linear correlation between average PE/PVA core/shell fiber diameter and polymerization time are made. At elevated pressure, this control is lost, accounting for the formation of reactor blends consisting of PE granules and built‐in PE/PVA nanofibers. Whereas conventional catalysts produce micrometer‐sized particles of ultrahigh molecular weight PE (UHMWPE), PVA‐nanofiber supported chromium catalysts afford new families UHMWPE materials. They range from UHMWPE/PVA core/shell nanofibers and nonwovens to hollow UHMWPE fibers and nanoporous UHMWPE, obtained by removing the PVA component.
Copper Nanoparticles from Copper Aluminum Hydrotalcite: An Efficient Catalyst for Acceptor‐ and Oxidant‐Free Dehydrogenation of Amines and Alcohols
Authors: Damodara Dandu , Arundhathi Racha , Likhar Pravin R.
Published: January 2014

An efficient and simple process for the preparation of stable nanocopper(0) on alumina [Cu(0)/Al2O3] from the inorganic composite precursor copper aluminum hydrotalcite (Cu‐Al HT) by a chemical reduction method is described. Cu(0)/Al2O3 was employed as an efficient catalyst in the acceptor‐ and oxidant‐free dehydrogenation of various amines and alcohols to their corresponding dehydrogenated products in good to excellent yields. The stability of Cu(0)/Al2O3 was assessed by studying its recoverability and reusability in the dehydrogenation of amines and alcohols for up to five cycles.

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Palladium‐Catalyzed Methoxylation of Aromatic Chlorides with Borate Salts
Authors: Tolnai Gergely L. , Pethő Bálint , Králl Péter , Novák Zoltán
Published: January 2014

Herein we disclose a simple palladium‐catalyzed transformation for the methoxylation of aromatic chlorides with tetramethoxyborate salts. The procedure provides a new and efficient synthetic tool for the introduction of a methoxy group into aromatic systems. In addition, the reaction can be achieved using a wide range of aromatic and heteroaromatic chlorides, the cheapest class of halides.

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New Polyimide and Nanoporous Structures with Low Dielectric Constant
Authors: Mehdipour‐Ataei Shahram , Aram Elham
Published: January 2014

A diamine containing pyridine ring, amide, and ether groups was prepared via two‐step reactions from 6‐chloronicotinoyl chloride. A novel polyimide was prepared from polycondensation of pyromellitic dianhydride with the diamine. In addition, nanoporous polyimide films were prepared from graft copolyimides. A thermally labile oligomer, poly(propylene glycol) (PPG), was incorporated into the polyimide backbone to obtain graft copolyimides that left voids into the polymer matrix through thermolysis of the labile PPG blocks. The properties of polyimide and nanofoams were compared. The dielectric constant of nanofoams was reduced, whereas their thermal stability and mechanical properties were almost maintained in comparison to the homopolyimide.
Distributed dissipative model predictive control for process networks with imperfect communication
Authors: Tippett Michael James , Bao Jie
Published: January 2014

Results are developed to ensure stability of a dissipative distributed model predictive controller in the case of structured or arbitrary failure of the controller communication network; bounded errors in the communication may similarly be handled. Stability and minimum performance of the process network is ensured by placing a dissipative trajectory constraint on each controller. This allows for the interaction effects between units to be captured in the dissipativity properties of each process, and thus, accounted for by choosing suitable dissipativity constraints for each controller. This approach is enabled by the use of quadratic difference forms as supply rates, which capture detailed dynamic system information. A case study is presented to illustrate the results. © 2014 American Institute of Chemical EngineersAIChE J, 60: 1682–1699, 2014
Intramolecular Interactions of a Phenyl/Perfluorophenyl Pair in the Formation of Supramolecular Nanofibers and Hydrogels
Authors: Hsu Shu‐Min , Lin Yu‐Chun , Chang Jui‐Wen , Liu Yu‐Hao , Lin Hsin‐Chieh
Published: January 2014

A new system for the incorporation of a phenyl/perfluorophenyl pair in the structure of a peptide hydrogelator was developed. The strategy is based on the idea that the integration of an end‐capped perfluorophenyl group and a phenylalanine with a phenyl moiety in the side chain forms an intramolecular phenyl/perfluorophenyl pair, which can be used to promote the formation of the supramolecular nanofibers and hydrogels. This work illustrates the importance of structure‐hydrogelation relationship and provides new insights into the design of self‐assembly nanobiomaterials.
Fiber‐Based Flexible All‐Solid‐State Asymmetric Supercapacitors for Integrated Photodetecting System
Authors: Wang Xianfu , Liu Bin , Liu Rong , Wang Qiufan , Hou Xiaojuan , Chen Di , Wang Rongming , Shen Guozhen
Published: January 2014

Integrated nanodevices with the capability of storing energy are widely applicable and have thus been studied extensively. To meet the demand for flexible integrated devices, all‐solid‐state asymmetric supercapacitors that simultaneously realize energy storage and optoelectronic detection were fabricated by growing Co3O4 nanowires on nickel fibers, thus giving the positive electrode, and employing graphene as both the negative electrode and light‐sensitive material. The as‐assembled integrated systems were characterized by an improved energy storage, enhanced power density (at least by 1860 % enhanced) by improving the potential window from 0–0.6 V to 0—1.5 V, excellent photoresponse to white light, and superior flexibility of both the fiber‐based asymmetric supercapacitor and the photodetector. Such flexible integrated devices might be used in smart and self‐powered sensory, wearable, and portable electronics.
Copper‐Catalyzed Intermolecular Trifluoromethylazidation of Alkenes: Convenient Access to CF3‐Containing Alkyl Azides
Authors: Wang Fei , Qi Xiaoxu , Liang Zhaoli , Chen Pinhong , Liu Guosheng
Published: January 2014

A novel copper‐catalyzed intermolecular trifluoromethylazidation of alkenes has been developed under mild reaction conditions. A variety of CF3‐containing organoazides were directly synthesized from a wide range of olefins, including activated and unactivated alkenes, and the resulting products can be easily transformed into the corresponding CF3‐containing amine derivatives.
Catalytic Asymmetric 1,2‐Addition of α‐Isothiocyanato Phosphonates: Synthesis of Chiral β‐Hydroxy‐ or β‐Amino‐Substituted α‐Amino Phosphonic Acid Derivatives
Authors: Cao Yi‐Ming , Shen Fang‐Fang , Zhang Fu‐Ting , Zhang Jin‐Long , Wang Rui
Published: January 2014

α‐Amino phosphonic acid derivatives are considered to be the most important structural analogues of α‐amino acids and have a very wide range of applications. However, approaches for the catalytic asymmetric synthesis of such useful compounds are very limited. In this work, simple, efficient, and versatile organocatalytic asymmetric 1,2‐addition reactions of α‐isothiocyanato phosphonate were developed. Through these processes, derivatives of β‐hydroxy‐α‐amino phosphonic acid and α,β‐diamino phosphonic acid, as well as highly functionalized phosphonate‐substituted spirooxindole, can be efficiently constructed (up to 99 % yield, d.r. >20:1, and >99 % ee). This novel method provides a new route for the enantioselective functionalization of α‐phosphonic acid derivatives.
Structure Elucidation and Total Synthesis of Kulkenon
Authors: Symkenberg Gerrit , Kalesse Markus
Published: January 2014

The impressive biological profile of secondary metabolites isolated from strains of Sorangium cellulosum prompted us to initiate synthetic studies on kulkenon, also isolated from Sorangium cellulosum. The synthesis features a syn‐selective vinylogous Kobayashi aldol reaction, recently developed by us, and a ring‐closing intramolecular Heck reaction as the pivotal transformations. Comparison of the NMR spectra of the authentic and synthetic material revealed that the proposed configuration had to be revised. A combination of molecular modeling and NOE experiments was used to propose the revised configuration, which was confirmed by a new synthesis.
Art, anatomy, and medicine: Is there a place for art in medical education?
Authors: Bell Lawrence T.O. , Evans Darrell J.R.
Published: January 2014

For many years art, anatomy and medicine have shared a close relationship, as demonstrated by Leonardo da Vinci's anatomical drawings and Andreas Vesalius' groundbreaking illustrated anatomical textbook from the 16th century. However, in the modern day, can art truly play an important role in medical education? Studies have suggested that art can be utilized to teach observational skills in medical students, a skill that is integral to patient examination but seldom taught directly within medical curricula. This article is a subjective survey that evaluates a student selected component (SSC) that explored the uses of art in medicine and investigates student perception on the relationship between the two. It also investigates whether these medical students believe that art can play a role in medical education, and more specifically whether analyzing art can play a role in developing observational skills in clinicians. An “Art in Medicine” 8‐week course was delivered to first year medical students at Brighton and Sussex Medical School. The use of art to improve observational skills was a core theme throughout. Feedback from the students suggests that they believe a strong association between art and medicine exists. It also showed a strong perception that art could play a role in medical education, and more specifically through analyzing art to positively develop clinical observational skills. The results of this subjective study, together with those from research from elsewhere, suggest that an art‐based approach to teaching observational skills may be worth serious consideration for inclusion in medical and other healthcare curricula. Anat Sci Educ 7: 370–378. © 2014 American Association of Anatomists.
Galectin‐3 disruption impaired tumoral angiogenesis by reducing VEGF secretion from TGFβ1‐induced macrophages
Authors: Machado Camila Maria Longo , Andrade Luciana Nogueira Sousa , Teixeira Verônica Rodrigues , Costa Fabrício Falconi , Melo Camila Morais , dos Santos Sofia Nascimento , Nonogaki Suely , Liu Fu‐Tong , Bernardes Emerson Soares , Camargo Anamaria Aranha , Chammas Roger
Published: January 2014

In order to study the role of galectin‐3 in tumor angiogenesis associated with tumor‐associated macrophages (TAM) and tumor parenchyma, the galectin‐3 expression was reconstituted in Tm1 melanoma cell line that lacks this protein. Galectin‐3‐expressing cells (Tm1G3) and mock‐vector transfected cells (Tm1N3) were injected into wild‐type (WT) and galectin‐3 knockout (KO) C57Bl/6 mice. Tumors originated from Tm1G3 were larger in tumor volume with enlarged functional vessels, decreased necrotic areas, and increased vascular endothelial growth factor (VEGF) protein levels. Galectin‐3‐nonexpressing‐cells injected into WT and KO showed increased levels of transforming growth factor beta 1 (TGFβ1) and, in WT animals this feature was also accompanied by increased VEGFR2 expression and its phosphorylation. In KO animals, tumors derived from galectin‐3‐expressing cells were infiltrated by CD68+‐cells, whereas in tumors derived from galectin‐3‐nonexpressing‐cells, CD68+ cells failed to infiltrate tumors and accumulated in the periphery of the tumor mass. In vitro studies showed that Tm1G3 secreted more VEGF than Tm1N3 cells. In the latter case, TGFβ1 induced VEGF production. Basal secretion of VEGF was higher in WT‐bone marrow‐derived macrophages (BMDM) than in KO‐BMDM. TGFβ1 induced secretion of VEGF only in WT‐BMDM. Tm1G3‐induced tumors had the Arginase I mRNA increased, which upregulated alternative macrophage (M2)/TAM induction. M2 stimuli, such as interleukin‐4 (IL4) and TGFβ1, increased Arginase I protein levels and galectin‐3 expression in WT‐ BMDM, but not in cells from KO mice. Hence, we report that galectin‐3 disruption in tumor stroma and parenchyma decreases angiogenesis through interfering with the responses of macrophages to the interdependent VEGF and TGFβ1 signaling pathways.
In which clinical scenario would awake fibreoptic nasal intubation be employed?
Authors: Kassam Karim , Rope Tasmin
Published: January 2014

Key Clinical Message

The routine way to access the uncomplicated airway is via direct laryngoscopy. When this is not possible, there are a number of other techniques to help visualization such as the video laryngoscopy. These require a degree of mouth opening. With almost complete trismus, the clinician should resort to awake fibreoptic nasal intubation to secure the airway.
Improved survival using intensity‐modulated radiation therapy in head and neck cancers: A SEER‐Medicare analysis
Authors: Beadle Beth M. , Liao Kai‐Ping , Elting Linda S. , Buchholz Thomas A. , Ang K. Kian , Garden Adam S. , Guadagnolo B. Ashleigh
Published: January 2014

BACKGROUND

Intensity‐modulated radiation therapy (IMRT) is a technologically advanced, and more expensive, method of delivering radiation therapy with a goal of minimizing toxicity. It has been widely adopted for head and neck cancers; however, its comparative impact on cancer control and survival remains unknown. The goal of this analysis was to compare the cause‐specific survival (CSS) for patients with head and neck cancers treated with IMRT versus non‐IMRT from 1999 to 2007.

METHODS

CSS was determined using the Surveillance, Epidemiology, and End Results (SEER)‐Medicare database and analyzed regarding treatment details, including the use of IMRT versus non‐IMRT, using claims data. Hazard ratios (HRs) were estimated by the frailty model with a propensity score matching cohort and instrumental variable analysis.

RESULTS

A total of 3172 patients were identified. With a median follow‐up of 40 months, patients treated with IMRT had a statistically significant improvement in CSS compared with those treated with non‐IMRT (84.1% versus 66.0%; P < .001). When each anatomic subsite was analyzed separately, all respective subgroups of patients treated with IMRT had better CSS than those treated with non‐IMRT. In multivariable survival analyses, patients treated with IMRT were associated with better CSS (HR = 0.72, 95% confidence interval  = 0.59 to 0.90 for propensity score matching; HR = 0.60, 95% confidence interval = 0.41 to 0.88 for instrumental variable analysis).

CONCLUSIONS

Patients with head and neck cancers who were treated with IMRT experienced significant improvements in CSS compared with patients treated with non‐IMRT techniques. This suggests there may be benefits to IMRT in cancer outcomes, in addition to toxicity reduction, for this patient population. Cancer 2014;120:702–710. © 2013 American Cancer Society.
Mice deficient in heparanase exhibit impaired dendritic cell migration and reduced airway inflammation
Authors: Poon Ivan K. H. , Goodall Katharine J. , Phipps Simon , Chow Jenny D. Y. , Pagler Eloisa B. , Andrews Daniel M. , Conlan Carly L. , Ryan Gemma F. , White Julie A. , Wong Michael K. L. , Horan Catherine , Matthaei Klaus I. , Smyth Mark J. , Hulett Mark D.
Published: January 2014

Heparanase is a β‐d‐endoglucuronidase that cleaves heparan sulphate, a key component of the ECM and basement membrane. The remodelling of the ECM by heparanase has been proposed to regulate both normal physiological and pathological processes, including wound healing, inflammation, tumour angiogenesis and cell migration. Heparanase is also known to exhibit non‐enzymatic functions by regulating cell adhesion, cell signalling and differentiation. In this study, constitutive heparanase‐deficient (Hpse−/−) mice were generated on a C57BL/6 background using the Cre/loxP recombination system, with a complete lack of heparanase mRNA, protein and activity. Although heparanase has been implicated in embryogenesis and development, Hpse−/− mice are anatomically normal and fertile. Interestingly, consistent with the suggested function of heparanase in cell migration, the trafficking of dendritic cells from the skin to the draining lymph nodes was markedly reduced in Hpse−/− mice. Furthermore, the ability of Hpse−/− mice to generate an allergic inflammatory response in the airways, a process that requires dendritic cell migration, was also impaired. These findings establish an important role for heparanase in immunity and identify the enzyme as a potential target for regulation of an immune response.
Aroma enhancement and enzymolysis regulation of grape wine using β‐glycosidase
Authors: Zhu Feng‐Mei , Du Bin , Li Jun
Published: January 2014

Adding β‐glycosidase into grape wine for enhancing aroma was investigated using gas chromatography‐mass spectrometry (GC‐MS) and Kramer sensory evaluation. Compared with the extract from control wines, the extract from enzyme‐treated wines increased more aromatic compounds using steam distillation extraction (SDE) and GC‐MS analyses. Theses aromatic compounds were as follows: 3‐methyl‐1‐butanol formate, 3‐pentanol, furfural, 3‐methyl‐butanoic acid, 2‐methyl‐butanoic acid, 3‐hydroxy‐butanoic acid ethyl ester, hexanoic acid, hexanoic acid ethyl ester, benzyl alcohol, octanoic acid, octanoic acid ethyl ester, dodecanoic acid, and ethyl ester. The enzymolysis regulation conditions, including enzymolysis temperature, enzymolysis time, and enzyme amount, were optimized through L9(34) orthogonal test. Kramer sensory evaluation was performed by an 11‐man panel of judges. The optimum enzymolysis regulation conditions were found to be temperature of 45°C, enzymolysis time of 90 min, and enzyme amount of 58.32 U/mL grape wine, respectively. The Kramer sensory evaluation supported that the enzyme‐treated wines produced a stronger fragrance.
Kinetics and Mechanism Studies on Dispersion of CNT in SDS Aqueous Solutions
Authors: Chen Jung‐Hui
Published: January 2014

The objects of this research are to study the dispersion of CNT (carbon nanotube) in SDS (sodium dodecyl sulfate) aqueous solutions with kinetics approach and to obtain some information about mechanism for this dispersion. Firstly, I measured the UV‐visible absorption at 260 nm of CNT in SDS aqueous solutions after different time of dispersion for different concentrations of CNT and SDS. Then, curves of the time‐dependent absorbance were analyzed by various mathematical models and were found to fit well with equation of A = A∞ exp(‐kobs t), where A∞ is the absorbance at infinite time and kobs is the observed rate constant. The values of A∞, kobs, and, minimum time for dispersion can be obtained. From the effects of concentrations of SDS and CNT on A∞ and kobs, the dissociation constant for CNT‐SDS complex and the optimum ratio of [CNT]/[SDS] can be estimated. Finally, the mechanism for this dispersion may be proposed as”

$\rm{b-CNT \xrightleftharpoons[\rm{k_{-1} \left[CNT\right]} ]{\rm{k_{1}}} CNT \xrightharpoon[]{\rm{k_{2} \left[SDS\right]}} CNT-SDS}$

where b‐CNT, CNT, CNT‐SDS, and, ki s are bounded CNT, exfoliated CNT, CNT‐SDS complex, and, the rate constants, respectively. In this mechanism, b‐CNT is firstly unbounded by supersonic energy to form CNT intermediate with rate constant of k1, which is proportional to the supersonic energy per time. The CNT intermediate then recombines to form b‐CNT with rate constant k−1[CNT] or reacts with SDS to form CNT‐SDS complex, which has absorbance at 260 nm in UV‐visible spectrum, with rate constant of k2 [SDS]. Details of kinetics and mechanism will be discussed in this paper.