Spectroscopic analysis of epoxidised jatropha oil (EJO) and acrylated epoxidised jatropha oil (AEJO)

The non-edible seed oil of the Jatropha plant is a renewable and sustainable material to produce vegetable oil-based epoxy and epoxy acrylate as raw polymeric material. The objective of this study is to synthesis Jatropha seed oil-based epoxy and acrylate epoxy resins through conventional methods. An epoxy ring of Epoxidised Jatropha Oil (EJO) was formed through an in-situ epoxidation process using hydrogen peroxide and formic acid as an oxygen donor and oxygen carrier respectively. Acrylated Epoxidised Jatropha Oil (AEJO) was produced by reacting EJO with acrylic acid with the existence of triethylamine and 4-methoxyphenol as a catalyst and inhibitor respectively. The measured oxirane-oxygen content (OOC) of EJO was 4.99%. The acid value of the AEJO was determined at 4.42 mg KOH/g. Both the EJO and AEJO were characterised by FTIR and 1H NMR spectroscopies

MELK is an oncogenic kinase essential for mitotic progression in basal-like breast cancer cells

Despite marked advances in breast cancer therapy, basal-like breast cancer (BBC), an aggressive subtype of breast cancer usually lacking estrogen and progesterone receptors, remains difficult to treat. In this study, we report the identification of MELK as a novel oncogenic kinase from an in vivo tumorigenesis screen using a kinome-wide open reading frames (ORFs) library. Analysis of clinical data reveals a high level of MELK overexpression in BBC, a feature that is largely dependent on FoxM1, a master mitotic transcription factor that is also found to be highly overexpressed in BBC. Ablation of MELK selectively impairs proliferation of basal-like, but not luminal breast cancer cells both in vitro and in vivo. Mechanistically, depletion of MELK in BBC cells induces caspase-dependent cell death, preceded by defective mitosis. Finally, we find that Melk is not required for mouse development and physiology. Together, these data indicate that MELK is a normally non-essential kinase, but is critical for BBC and thus represents a promising selective therapeutic target for the most aggressive subtype of breast cancer. DOI: http://dx.doi.org/10.7554/eLife.01763.00

Mapping interactions with the chaperone network reveals factors that protect against tau aggregation.

A network of molecular chaperones is known to bind proteins ('clients') and balance their folding, function and turnover. However, it is often unclear which chaperones are critical for selective recognition of individual clients. It is also not clear why these key chaperones might fail in protein-aggregation diseases. Here, we utilized human microtubule-associated protein tau (MAPT or tau) as a model client to survey interactions between ~30 purified chaperones and ~20 disease-associated tau variants (~600 combinations). From this large-scale analysis, we identified human DnaJA2 as an unexpected, but potent, inhibitor of tau aggregation. DnaJA2 levels were correlated with tau pathology in human brains, supporting the idea that it is an important regulator of tau homeostasis. Of note, we found that some disease-associated tau variants were relatively immune to interactions with chaperones, suggesting a model in which avoiding physical recognition by chaperone networks may contribute to disease

Single-particle measurements of electrochemical kinetics in NMC and NCA cathodes for Li-ion batteries

The electrochemical kinetics of battery electrodes at the single-particle scale are measured as a function of state-of-charge, and interpreted with the aid of concurrent transmission X-ray microscopy (TXM) of the evolving particle microstructure. An electrochemical cell operating with near-picoampere current resolution is used to characterize single secondary particles of two widely-used cathode compounds, NMC333 and NCA. Interfacial charge transfer kinetics are found to vary by two orders of magnitude with state-of-charge (SOC) in both materials, but the origin of the SOC dependence differs greatly. NCA behavior is dominated by electrochemically-induced microfracture, although thin binder coatings significantly ameliorate mechanical degradation, while NMC333 demonstrates strongly increasing interfacial reaction rates with SOC for chemical reasons. Micro-PITT is used to separate interfacial and bulk transport rates, and show that for commercially relevant particle sizes, interfacial transport is rate-limiting at low SOC, while mixed-control dominates at higher SOC. These results provide mechanistic insight into the mesoscale kinetics of ion intercalation compounds, which can guide the development of high performance rechargeable batteries

A case study of Singapore Management University Libraries: Adopting a mixed methods approach towards collection evaluation

With rising costs and limited resources, it has become increasingly important for academic libraries to make acquisition decisions prudently to build a collection that meets its users' learning, teaching, and research needs. As such, Singapore Management University's (“SMU”) Libraries use a patron-driven acquisitions process, whereby acquisition decisions are guided by users' needs and requests. This article seeks to investigate if the current patron-driven acquisitions approach adequately meets the research needs of SMU's users through a mixed methods approach. A collection analysis was first conducted on the SMU Libraries' publications' references from the years 2017 to 2018 using the Scopus database. To ensure that the results of the study were valid and reliable, this study also analysed the Library Service Quality Survey for 2018, in addition to interviews with selected undergraduate and postgraduate students. This resulted in the triangulation of these results enabling comparison and analysis across a range of dimensions. The findings show that the library collection was largely able to meet users' needs. Most of the cited publications could be found in the library collection, and users were satisfied with the collection. However, there was a lack of awareness of library resources and how to use them effectively

Improvement of anticorrosion coating properties in bio-based polymer epoxy acrylate incorporated with nano zinc oxide particles

A new green binder of Jatropha-oil based epoxy acrylate (AEJO) resin was able to replace coatings in non-ecology-friendly technologies. The epoxy acrylate coating was blended with nano zinc oxide to make hybrid nanocomposites as a corrosion protection coating applied to a mild steel panel. AEJO was synthesized and incorporated with different loadings (1, 3, 5, 7, and 9 wt %) of zinc oxide (ZnO) fillers. The AEJO/ZnO coating was applied on the mild steel substrates and characterized for corrosion protection performance by impedance spectroscopy (EIS) and salt spray tests. XRD analysis was conducted, and thermal properties by TGA were studied. The surface morphology of the hybrid coating was characterized by field emission scanning electron microscopy (FE-SEM). Incorporation of a 5 wt % ZnO loading showed significantly enhanced corrosion resistance through EIS as well as coating performance. This study provides green-based materials and protection to surface and interface engineering

The North American Multi-Model Ensemble (NMME): Phase-1 Seasonal to Interannual Prediction, Phase-2 Toward Developing Intra-Seasonal Prediction

The recent US National Academies report "Assessment of Intraseasonal to Interannual Climate Prediction and Predictability" was unequivocal in recommending the need for the development of a North American Multi-Model Ensemble (NMME) operational predictive capability. Indeed, this effort is required to meet the specific tailored regional prediction and decision support needs of a large community of climate information users. The multi-model ensemble approach has proven extremely effective at quantifying prediction uncertainty due to uncertainty in model formulation, and has proven to produce better prediction quality (on average) then any single model ensemble. This multi-model approach is the basis for several international collaborative prediction research efforts, an operational European system and there are numerous examples of how this multi-model ensemble approach yields superior forecasts compared to any single model. Based on two NOAA Climate Test Bed (CTB) NMME workshops (February 18, and April 8, 2011) a collaborative and coordinated implementation strategy for a NMME prediction system has been developed and is currently delivering real-time seasonal-to-interannual predictions on the NOAA Climate Prediction Center (CPC) operational schedule. The hindcast and real-time prediction data is readily available (e.g., http://iridl.ldeo.columbia.edu/SOURCES/.Models/.NMME/) and in graphical format from CPC (http://origin.cpc.ncep.noaa.gov/products/people/wd51yf/NMME/index.html). Moreover, the NMME forecast are already currently being used as guidance for operational forecasters. This paper describes the new NMME effort, presents an overview of the multi-model forecast quality, and the complementary skill associated with individual models

Thienoisoindigo-Based Semiconductor Nanowires Assembled with 2-Bromobenzaldehyde via Both Halogen and Chalcogen Bonding

We fabricated nanowires of a conjugated oligomer and applied them to organic field-effect transistors (OFETs). The supramolecular assemblies of a thienoisoindigo-based small molecular organic semiconductor (TIIG-Bz) were prepared by co-precipitation with 2-bromobenzaldehyde (2-BBA) via a combination of halogen bonding (XB) between the bromide in 2-BBA and electron-donor groups in TIIG-Bz, and chalcogen bonding (CB) between the aldehyde in 2-BBA and sulfur in TIIG-Bz. It was found that 2-BBA could be incorporated into the conjugated planes of TIIG-Bz via XB and CB pairs, thereby increasing the pi - pi stacking area between the conjugated planes. As a result, the driving force for one-dimensional growth of the supramolecular assemblies via pi - pi stacking was significantly enhanced. TIIG-Bz/2-BBA nanowires were used to fabricate OFETs, showing significantly enhanced charge transfer mobility compared to OFETs based on pure TIIG-Bz thin films and nanowires, which demonstrates the benefit of nanowire fabrication using 2-BB

Chemically induced self-assembly of spherical and anisotropic inorganic nanocrystals

The self-assembly of inorganic nanoparticles is a research area of great interest aiming at the fabricationof unique mesostructured materials with intrinsic properties. Although many assembly strategies have been reportedover the years, chemically induced self-assembly remains one of the dominant approaches to achieve a high levelof nanoparticle organization. In this feature article we review the latest developments in assembly drivenby the active manipulation of nanoparticle surface

Deletion of individual Ku subunits in mice causes an NHEJ-independent phenotype potentially by altering apurinic/apyrimidinic site repair

Ku70 and Ku80 form a heterodimer called Ku that forms a holoenzyme with DNA dependent-protein kinase catalytic subunit (DNA-PKCS) to repair DNA double strand breaks (DSBs) through the nonhomologous end joining (NHEJ) pathway. As expected mutating these genes in mice caused a similar DSB repair-defective phenotype. However, ku70-/- cells and ku80 -/- cells also appeared to have a defect in base excision repair (BER). BER corrects base lesions, apurinic/apyrimidinic (AP) sites and single stand breaks (SSBs) utilizing a variety of proteins including glycosylases, AP endonuclease 1 (APE1) and DNA Polymerase β (Pol β). In addition, deleting Ku70 was not equivalent to deleting Ku80 in cells and mice. Therefore, we hypothesized that free Ku70 (not bound to Ku80) and/or free Ku80 (not bound to Ku70) possessed activity that influenced BER. To further test this hypothesis we performed two general sets of experiments. The first set showed that deleting either Ku70 or Ku80 caused an NHEJ-independent defect. We found ku80-/- mice had a shorter life span than dna-pkcs-/- mice demonstrating a phenotype that was greater than deleting the holoenzyme. We also found Ku70-deletion induced a p53 response that reduced the level of small mutations in the brain suggesting defective BER. We further confirmed that Ku80-deletion impaired BER via a mechanism that was not epistatic to Pol β. The second set of experiments showed that free Ku70 and free Ku80 could influence BER. We observed that deletion of either Ku70 or Ku80, but not both, increased sensitivity of cells to CRT0044876 (CRT), an agent that interferes with APE1. In addition, free Ku70 and free Ku80 bound to AP sites and in the case of Ku70 inhibited APE1 activity. These observations support a novel role for free Ku70 and free Ku80 in altering BER. © 2014 Choi et al