619 research outputs found

    The impacts of academic and industry research on high-tech manufacturing: Evidence from supercomputer usage

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    It is widely accepted that research in the high-tech sector is considered a key to maintain advanced economiesā€™ competitiveness at the face of their emerging counterpartsā€™ rising technological sophistication. Yet, the impact of research on high-tech output has never been quantified. In this paper, we empirically examine the impact of frontier research on high-tech manufacturing production. Standard R&D expenditure measure is found to be too general to capture the input in frontier research. To overcome this problem, we propose a novel proxy for frontier research investment ā€“ the supercomputing capacity. Empirical evidence strongly supports this choice of variable. We also find that academic research exerts a larger growth effect on high-tech manufacturing output than its industrial counterpart.

    Effect of cyclosporine on hepatic cytosolic estrogen and androgen receptor levels before and after partial hepatectomy

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    Estrogen and androgen receptors within the liver have been reported to modulate the hepatic regenerative response to partial hepatectomy. Moreover, cyclosporine has several untoward effects that might occur as a consequence of alterations in sex hormone activity. To evaluate these questions the following experiments were performed. Estrogen and androgen receptors in cytosol were quantitated in livers of rats treated with cyclosporine or olive oil vehicle before and after partial hepatectomy or a sham operation. Ornithine decarboxylase activity and thymidine kinase activity were assessed as indices of hepatic regeneration. Preoperative levels of estrogen receptor activity in the hepatic cytosol were significantly greater in rats treated with cyclosporine as compared to vehicle treated controls (P<0.01). In contrast, preoperative levels of androgen receptor activity in the cyclosporine-treated and vehicle-treated animals were similar. Following partial hepatectomy, a reduction in the activity of both sex hormone receptors in the hepatic cytosol was observed and was compatible with results described previously in normal animals. Unexpectedly the preoperative levels of ornithine decarboxylase (P<0.01) and thymidine kinase activity (P<0.01) were significantly greater in the rats treated with cyclosporine as compared to the vehicle treated controls. As expected, ornithine decarboxylase activity (at 6 hr) and thymidine kinase activity (at 24 hr) rose and peaked in response to a partial hepatectomy but were significantly greater (P<0.05) in the rats treated with cyclosporine as compared to the vehicle. These results show that cyclosporine treatment causes an increase in the hepatic content of estrogen receptor activity that is associated with an enhanced potential for a regenerative response. These effects of cyclosporine treatment on the sex hormone receptor levels in liver may explain the mechanisms responsible for some of the untoward effects of treatment with this agent. Ā© 1990 Plenum Publishing Corporation

    Treatment with Methylphenidate for Attention Deficit Hyperactivity Disorder (ADHD) and the Risk of All-Cause Poisoning in Children and Adolescents:A Self-Controlled Case Series Study

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    BACKGROUND: Children and adolescents with attention deficit hyperactivity disorder (ADHD) are at higher risk of all-cause poisoning by drugs and chemicals (intentional or accidental). Currently, there is limited data on whether medication treatment for ADHD can reduce the risk of all-cause poisoning. METHODS: Patients aged 5ā€“18 years with a methylphenidate (MPH) prescription and an incident poisoning diagnosis between January 2001 and June 2020 were identified from the Hong Kong Clinical Data Analysis and Reporting System. A self-controlled case series study design was used to compare the incidence rate ratios (IRRs) of all-cause poisoning during different risk windows (30 days before the first MPH prescription, exposure periods within 30 days of the first prescription, and periods of subsequent exposure) compared with the reference window (other non-exposure periods). RESULTS: 42,203 patients were prescribed ADHD medication in Hong Kong during the study period. Of these, 417 patients who had both an MPH prescription and poisoning incident recorded were included in the main analysis. Compared with other non-exposed periods, a higher risk of poisoning was found in the 30 days before the first prescription (IRR 2.64, 95% confidence interval [CI] 1.33ā€“5.22) and exposure periods within 30 days of the first prescription (IRR 2.18, 95% CI 1.06ā€“4.48), but not during prolonged exposure. However, compared with 30 days before the first prescription as well as exposure periods within 30 days of the first prescription, there was a lower risk during the subsequent exposure (IRRs 0.49 and 0.60, respectively). Similar results to the main analysis were also found in the subgroup analysis of intentional poisoning and females, but not in that of accidental poisoning and males. CONCLUSIONS: The risk of all-cause poisoning was higher shortly before and after the first MPH prescription and became lower during the subsequent prescription period. Our results do not support an association between the use of MPH and an increased risk of all-cause poisoning in children and adolescents and, in fact, suggest that longer-term use of MPH may be associated with a lower risk of all-cause poisoning, although this latter finding requires further study. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40263-021-00824-x

    Nanoparticle-mediated intracellular lipid accumulation during C2C12 cell differentiation

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    In this report, we sought to elucidate whether multiwall carbon nanotubes are involved in the modulation of the proliferation and differentiation of the skeletal muscle cell line C2C12. Skeletal muscle is a major mass peripheral tissue that accounts for 40% of total body weight and 50% of energy consumption. We focused on the differentiation pathway of myoblasts after exposure to a vapor-grown carbon fiber, HTT2800, which is one of the most highly purified carbon nanotubes. This treatment leads in parallel to the expression of a typical adipose differentiation program. We found that HTT2800 stimulated intracellular lipid accumulation in C2C12 cells. We have also shown by quantified PCR analysis that the expression of adipose-related genes was markedly upregulated during HTT2800 exposure. Taken together, these results suggest that HTT2800 specifically converts the differentiation pathway of C2C12 myoblasts to that of adipoblast-like cells

    Identification of a Novel Recycling Sequence in the C-tail of FPR2/ALX Receptor: Association with Cell Protection from Apoptosis

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    Formyl-peptide receptor type 2 (FPR2; also called ALX because it is the receptor for lipoxin A4) sustains a variety of biological responses relevant to the development and control of inflammation, yet the cellular regulation of this G-protein-coupled receptor remains unexplored. Here we report that, in response to peptide agonist activation, FPR2/ALX undergoes Ī²-arrestin-mediated endocytosis followed by rapid recycling to the plasma membrane. We identify a transplantable recycling sequence that is both necessary and sufficient for efficient receptor recycling. Furthermore, removal of this C-terminal recycling sequence alters the endocytic fate of FPR2/ALX and evokes pro-apoptotic effects in response to agonist activation. This study demonstrates the importance of endocytic recycling in the anti-apoptotic properties of FPR2/ALX and identifies the molecular determinant required for modulation of this process fundamental for the control of inflammation

    A Biodesigned Nanocomposite Biomaterial for Auricular Cartilage Reconstruction

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    Current biomaterials for auricular replacement are associated with high rates of infection and extrusion. The development of new auricular biomaterials that mimic the mechanical properties of native tissue and promote desirable cellular interactions may prevent implant failure. A porous 3D nanocomposite scaffold (NS) based on POSS-PCU (polyhedral oligomeric silsesquioxane nanocage into polycarbonate based urea-urethane) is developed with an elastic modulus similar to native ear. In vitro biological interactions on this NS reveal greater protein adsorption, increased fibroblast adhesion, proliferation, and collagen production compared with Medpor (the current synthetic auricular implant). In vivo, the POSS-PCU with larger pores (NS2; 150-250 Ī¼m) have greater tissue ingrowth (ā‰ˆ5.8Ɨ and ā‰ˆ1.4 Ɨ increase) than the POSS-PCU with smaller pores (NS1; 100-50 Ī¼m) and when compared to Medpor (>100 Ī¼m). The NS2 with the larger pores demonstrates a reduced fibrotic encapsulation compared with NS1 and Medpor (ā‰ˆ4.1Ɨ and ā‰ˆ1.6Ɨ, respectively; P < 0.05). Porosity also influences the amount of neovascularization within the implants, with no blood vessel observed in NS1 (12 weeks postimplantation). The lack of chronic inflammatory response for all materials may indicate that the elastic modulus and pore size of the implant scaffold could be important design considerations for influencing fibrotic responses to auricular and other soft tissue implants

    Structure and magnetic properties of the AB(HCO2)3 (A = Rb+ or Cs+, B = Mn2+, Co2+ or Ni2+) frameworks: probing the effect of size on the phase evolution of the ternary formates

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    This work reports the synthesis and structures of six new AB(HCO2)3 (A = Rb+ or Cs+ and B = Mn2+, Co2+ or Ni2+) frameworks containing the largest monoatomic cations on the A-site. RbMn(HCO2)3 is found to adopt a distorted perovskite framework with a 412[middle dot]63 topology and a mixture of syn-anti and anti-anti ligands, while the remaining compounds adopt a chiral hexagonal structure with a 49[middle dot]66 topology. The structures of these frameworks clarify the effect of ionic size on the formation of the five known architectures adopted by the AB(HCO2)3 frameworks, which have attracted attention as a new class of potential multiferroics, and in particular the chiral hexagonal structure within this. This also highlights the role of molecular A-site cations in stabilising the 49[middle dot]66 topology for frameworks where such cations are too large or small to support this structure on the basis of size alone, possibly due to hydrogen bonding. The magnetic properties of the RbB(HCO2)3 and CsMn(HCO2)3 frameworks are also reported with the Rb+ compounds featuring weak ferromagnetic behaviour and the latter being purely antiferromagnetic. In conjunction with a comparison of the other isostructural AB(HCO2)3 frameworks we find that compounds adopting the 49[middle dot]66 topology have much higher magnetic ordering temperatures than those with the RbMn(HCO2)3 structure, highlighting the importance of understanding the structure-property relationships of the ternary formates
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