ALBERT

Description: Four model polyurethane (PU) hard segments were synthesized by reaction of butanol with four typical diisocyanates. The four diisocyanates were aromatic 4,4'-diphenylmethane diisocyanate (4,4'-MDI) and MDI-50 (50% mixture of 2,4'-MDI and 4,4'-MDI), cycloaliphatic 4,4'-dicyclohexylmethane diisocyanate (HMDI) and linear aliphatic 1,6-hexamethylene diisocyanate (HDI). FTIR, 1 H NMR, 13 C NMR, MS, X-ray and DSC methods were employed to determine their structures and to analyse their crystallization behaviours and hydrogen bonding interactions. Each of the four PU compounds prepared in the present work displays unique spectral characteristics. The FTIR bands and NMR resonance peaks assigned in the four samples thus provide a reliable database and starting point for investigating the relationship between hard segment structure and the crystallization and hydrogen bonding behaviour in more complex-segmented PU compositions.

Description: Transcription factors (TFs) are families of proteins that bind to specific DNA sequences, or TF response elements (TFREs), and function as regulators of many cellular processes. Because of the low abundance of TFs, direct quantitative measurement of TFs on a proteome scale remains a challenge. In this study, we report...

Description: Embryonic stem cell-based therapies exhibit great potential for the treatment of Parkinson’s disease (PD) because they can significantly rescue PD-like behaviors. However, whether the transplanted cells themselves release dopamine in vivo remains elusive. We and others have recently induced human embryonic stem cells into primitive neural stem cells (pNSCs) that...

Description: 〈p〉IL-6/STAT3 signaling is known to initiate the T〈sub〉H〈/sub〉17 differentiation program, but the upstream regulatory mechanisms remain minimally explored. Here, we show that Cxxc finger protein 1 (Cxxc1) promoted the generation of T〈sub〉H〈/sub〉17 cells as an epigenetic regulator and prevented their differentiation into T〈sub〉reg〈/sub〉 cells. Mice with a T cell–specific deletion of Cxxc1 were protected from experimental autoimmune encephalomyelitis and were more susceptible to 〈i〉Citrobacter rodentium〈/i〉 infection. Cxxc1 deficiency decreased IL-6Rα expression and impeded IL-6/STAT3 signaling, whereas the overexpression of IL-6Rα could partially reverse the defects in 〈i〉Cxxc1〈/i〉-deficient T〈sub〉H〈/sub〉17 cells in vitro and in vivo. Genome-wide occupancy analysis revealed that Cxxc1 bound to 〈i〉Il6r〈/i〉α gene loci by maintaining the appropriate H3K4me3 modification of its promoter. Therefore, these data highlight that Cxxc1 as a key regulator governs the balance between T〈sub〉H〈/sub〉17 and T〈sub〉reg〈/sub〉 cells by controlling the expression of IL-6Rα, which affects IL-6/STAT3 signaling and has an impact on T〈sub〉H〈/sub〉17-related autoimmune diseases.〈/p〉

Description: This paper presents a dynamic plasmapause location model established based on five years of THEMIS measurements from 2009 to 2013. In total, 5878 plasmapause crossing events are identified, sufficiently covering all 24 Magnetic Local Time (MLT) sectors. Based on this plasmapause crossing database, we investigate the correlations between plasmapause locations with solar wind parameters and geomagnetic indices. Input parameters for the best fits are obtained for different MLT sectors and finally we choose five input parameters to build a plasmapause location model, including five-minute-averaged SYM-H, AL and AU indices as well as hourly-averaged AE and Kp indices. An out-of-sample comparison on the evolution of the plasmapause is shown during the April 2001 magnetic storm, demonstrating good agreement between model results and observations. Two major advantages are achieved by this model. First, this model provides plasmapause locations at 24 MLT sectors, still providing good consistency with observations. Second, this model is able to reproduce dynamic variations of the plasmapause on time scales as short as five minutes.

Description: This study integrates new and extant zircon U-Pb age and Hf isotope data, whole-rock Nd-Sr isotope data, and geochemistry data from the Chinese Altay (CA) and adjacent areas, in an attempt to identify the source rocks of granitoids and acidic-intermediate volcanic rocks and, hence, continental-crust growth in the CA. The protolith of the gneisses includes the earliest products of erosion from the surface rocks of the island arc volcanics and the syn- and post-collisional granitoids of the Caledonian orogenic-mountain system, whereas the provenance of metasedimentary rocks was exposed from increasingly deeper levels or from an expanded region that evolved from the axis to the flank of the mountain system as it was denuded until planation such that eroded material from the Tuva-Mongol microcontinental block to the east could be delivered to the CA. The CA tends to be more mafic and isotopically more primitive with depth, because material eroded early constitutes the lower section and material eroded late constitutes the upper section of the Early-Paleozoic sedimentary-pile.Source rocks for the granitoids and acidic-intermediate volcanic rocks of the CA include the eroded material from the microcontinental block, the eroded material from the syn- and post-collisional granitoids of the Caledonian province, MORB-type mafic rocks, and a minor component from the metasomatized lithospheric-mantle. Eroded material from the terrains north of the CA was first deposited as an Early-Paleozoic sedimentary-pile in the CA. The top section of this pile was again eroded and transported to the trench at the CA continental margin, and these second-round sediments were subducted beneath the CA accretionary wedge. The un-eroded lower section of the Early-Paleozoic sedimentary-pile lay at bottom of the CA accretionary wedge that was underplated by MORB-type mafic rocks.The CA granitoids can be divided into orogenic (460-360 Ma) and post-orogenic (~320-260 Ma). The orogenic granitoids can be subdivided into Groups 1 (ɛNd (t) 〈 +1) and 2 (ɛNd (t) mostly higher than +1). The main branch of the granitoids (67 data) that includes Group 1 and a majority of Group 2 were derived mainly from eroded materials from the Caledonian province and the Tuva-Mongol microcontinental block. The source rock of acidic-intermediate volcanic rocks was dominantly eroded materials from the latter. The granitoids in the Erqisi nappe at the junction between the CA and the Junggar are characterized by a mixed source between MORB-like mafic rocks and juvenile crustal-rocks. The Mid-Devonian dacite-rhyolite and dolerite dikes in the west Chinese Altay were derived from metasomatized lithospheric-mantle.Integrated isotope and geochemistry data further constrain the source compositions of granitoids. The granitoids in the northwest Chinese Altay were mainly derived from subducted sediment that was eroded from the top section of the Early-Paleozoic sedimentary-pile, whereas those in the east Chinese Altay were derived dominantly from the lower section of the pile. The source rock of the granitoids in the northeast of the middle Chinese Altay consists of the lower section of the Early-Paleozoic sedimentary-pile; and sediment, quartz keratophyre, and keratophyre that were subducted or thrust beneath the northern Chinese Altay. The main source rock of the granitoids in the southwest of the middle Chinese Altay varies between the subducted sediment in the westernmost segment and the lower section of the Early-Paleozoic sedimentary-pile and the mafic underplate to the east.A geophysical-sounding profile across the CA and East Junggar reveals a three-layer structure of the CA accretionary-wedge underplated by an oceanic lithosphere that was detached from the downgoing oceanic-spreading-center. From the Silurian to the Mid-Late Devonian, the active spreading-center was repeatedly subducted beneath the CA along a southwestward-retreating subduction zone as represented successively by four NE-dipping thrust faults that converge to a low-angle décollement at depth. Asthenospheric upwelling heated and melted the subducted sediment and the lower section of the Early-Paleozoic sedimentary-pile, along with the mafic underplate and generated the acidic-intermediate volcanic rocks and granitoids that culminated at ~400 Ma. During the Mid-Devonian, shallow dipping dècollement-like subduction changed to a steeply dipping subduction beneath the lithospheric-mantle wedge. The mantle wedge shielded the CA crust from heating from the subducting spreading-center, which resulted in waning granitoid magmatism from ~400 Ma to ~360 Ma.In conclusion, there was massive granitoid production but not massive continental-crust growth in the CA at ~400 Ma.

Description: 〈p〉The ruminants are one of the most successful mammalian lineages, exhibiting morphological and habitat diversity and containing several key livestock species. To better understand their evolution, we generated and analyzed de novo assembled genomes of 44 ruminant species, representing all six Ruminantia families. We used these genomes to create a time-calibrated phylogeny to resolve topological controversies, overcoming the challenges of incomplete lineage sorting. Population dynamic analyses show that population declines commenced between 100,000 and 50,000 years ago, which is concomitant with expansion in human populations. We also reveal genes and regulatory elements that possibly contribute to the evolution of the digestive system, cranial appendages, immune system, metabolism, body size, cursorial locomotion, and dentition of the ruminants.〈/p〉

Description: Existing theories of geographical specialization and trade can be classified into four groups: supply-side; demand-side; endogenous growth and institutional models. In the recent past, economic geographers have paid little attention to earlier regional economic analysis and concentrated for the most part on detailed examination of production structures, the chains linking upstream and downstream activities into production and value networks, clusters, institutions and more recently, economic evolution. As a result, existing economic geography is ill-equipped to deal with the impact of some aspects of the evolution of costs, exchange rates, trade and capital flows on regional development and pays relatively little attention to economic calculation. Geographical economics includes an underlying theory of trade and micro-foundations, yet its supply-side approach neglects the role of monetary and demand-side (except in gravity models of trade) factors. The aim of this article is to argue for an extension of existing theoretical frameworks to embrace these issues in the light of recent trends in global economic geography and successive financial and debt crises that have stricken the developed world.

Description: The promise of cell therapy for repair and restoration of damaged tissues or organs relies on administration of large dose of cells whose healing benefits are still limited and sometimes irreproducible due to uncontrollable cell loss and death at lesion sites. Using a large amount of therapeutic cells increases the...

Description: The Tibetan Plateau uplift and Cenozoic global cooling are thought to induce enhanced aridification in the Asian interior. Although the onset of Asian desertification is proposed to have started in the earliest Miocene, prevailing desert environment in the Tarim Basin, currently providing much of the Asian eolian dust sources, is...