45 research outputs found

    Prenatal Lead Levels, Plasma Amyloid ÎČ Levels, and Gene Expression in Young Adulthood

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    Background: Animal studies suggest that early-life lead exposure influences gene expression and production of proteins associated with Alzheimer’s disease (AD)

    Proximity-induced quasi-one-dimensional superconducting quantum anomalous Hall state: a promising scalable top-down approach towards localized Majorana modes

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    In this work, ~100 nm wide quantum anomalous Hall insulator (QAHI) nanoribbons are etched from a two-dimensional QAHI film. One part of the nanoribbon is covered with superconducting Nb, while the other part is connected to an Au lead via two-dimensional QAHI regions. Andreev reflection spectroscopy measurements were performed, and multiple in-gap conductance peaks were observed in three different devices. In the presence of an increasing magnetic field perpendicular to the QAHI film, the multiple in-gap peak structure evolves into a single zero-bias conductance peak (ZBCP). Theoretical simulations suggest that the measurements are consistent with the scenario that the increasing magnetic field drives the nanoribbons from a multi-channel occupied regime to a single channel occupied regime, and that the ZBCP may be induced by zero energy Majorana modes as previously predicted [24]. Although further experiments are needed to clarify the nature of the ZBCP, we provide initial evidence that quasi-1D QAHI nanoribbon/superconductor heterostructures are new and promising platforms for realizing zero-energy Majorana modes

    Evaluation on the effectiveness of organic acids combination against Ganoderma boninense, the causal pathogen of basal stem rot in oil palm

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    Basal Stem Rot (BSR) disease mainly caused by Ganoderma boninense has become a serious threat to the South East Asia oil palm industry. With no conclusive remedy to date, the oil palm industry is still in search of effective ways to manage this disease. The present work reports the effectiveness of organic acids combination (OAC) in managing Ganoderma infection in oil palm. In this study, the pre-formulated organic acids combination from a product to control BSR caused by Ganoderma was carried out both in the field and nursery. The trial was conducted for a duration of approximately 18 months. The field trial was carried out at Bode Estate of Kretam Plantations Sabah in Sandakan. The possibility of the OAC in preventing the infection from spreading to newly planted seedlings in the area with Ganoderma history was also assessed via nursery trial at Mile 25, estate of Kam Cheong Sdn Bhd. In the field trial, three different sets of protocols i.e.: A (0.4% v/v with 5 rounds of application), B (0.4% v/v with 3 rounds of application), and C (0.5% v/v with 3 rounds of application) of the OAC treatment were applied along with Ganoderma Selective Medium (GSM) analysis, ergosterol content analysis, in vitro antagonistic evaluation and Scanning Electron Microscope (SEM) observation to comprehensively investigate the efficacy of the combination. Protocols A, B and C had significantly reduced the colonisation / amount of ergosterol content (8.832-9.095 ÎŒg/g of trunk tissues) in the infected palms in comparison to those Ganoderma infected but left untreated palms (48.956 ÎŒg/g of trunk tissues). However, there was no significant difference between the effectiveness among the three protocols in reduction of Ganoderma colonisation till month-12, in which protocol C proved to perform better compared to the other two protocols. There was slight ergosterol content increment in oil palm tissues treated with various protocols of the OAC at month-18, but were much lesser compared to untreated palms. Nonetheless, none of the protocols in application of OAC gave an absolute control of Ganoderma till the end of the trial, as the treated palms remained infected but with much lower ergosterol content compared to untreated palms. Application of the OAC as soil treatment for prevention of Ganoderma infection to seedlings replanted in the area with Ganoderma history in Kam Cheong Estate showed lesser disease incidences compared to those untreated ones. The infected seedlings which were treated by this product also showed lesser amount of ergosterol content which represents lesser colonisation of the pathogenic fungi. However, OAC-treated seedlings still recorded the presence of ergosterol from low to moderate in some of the tested samples. In vitro experiment of OAC and Ganoderma mycelia further elaborates the possible interaction between these organic acids with Ganoderma when in contact with either the tissues or soil. The in vitro results suggest OAC has destructive effect against the mycelia of Ganoderma with SEM evidences of massive damaging effects of the product to the mycelia of the fungi. Based on the GC-MS analysis, the OAC were identified from the products propanoic acid, acetic acid, benzoic acid, sorbic acid and besylic acid

    3D bioactive composite scaffolds for bone tissue engineering

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    Bone is the second most commonly transplanted tissue worldwide, with over four million operations using bone grafts or bone substitute materials annually to treat bone defects. However, significant limitations affect current treatment options and clinical demand for bone grafts continues to rise due to conditions such as trauma, cancer, infection and arthritis. Developing bioactive three-dimensional (3D) scaffolds to support bone regeneration has therefore become a key area of focus within bone tissue engineering (BTE). A variety of materials and manufacturing methods including 3D printing have been used to create novel alternatives to traditional bone grafts. However, individual groups of materials including polymers, ceramics and hydrogels have been unable to fully replicate the properties of bone when used alone. Favourable material properties can be combined and bioactivity improved when groups of materials are used together in composite 3D scaffolds. This review will therefore consider the ideal properties of bioactive composite 3D scaffolds and examine recent use of polymers, hydrogels, metals, ceramics and bio-glasses in BTE. Scaffold fabrication methodology, mechanical performance, biocompatibility, bioactivity, and potential clinical translations will be discussed

    Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

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    Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≄30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≄90 days, chronic dialysis for ≄90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie

    Doing being observed: Experimenting with collaborative focus group analysis in post-Umbrella Movement Hong Kong

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    Democratising social inquiry is particularly relevant in the context of Hong Kong’s recent social movements, where political divisions have created rifts among families and friends. In exploring the Umbrella Movement’s personal impact on activists, bystanders and opponents, we developed a new methodology: collaborative focus group analysis (CFGA). Designed to create a safe space for communicating political differences, the methodology also aims to break down the distinction between researchers and researched and engages the latter as co-researchers. In our first application of CFGA, solidarity was exhibited across political and cultural divides, demonstrating the methodology’s potential to support collaborative knowledge-making among co-researchers with different political stances and educational and cultural backgrounds. By analysing the patterns of interaction that emerged within CFGA, we identify strategies for building ‘situated solidarity’ and maintaining ‘non-hierarchical dialogues’. In so doing, we assess CFGA’s potential and limitations

    Problematizing Hongkonger Political Subjectivity: The Struggle for, and over, Democracy

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    In this chapter we explore changing and competing political subjectivities in Hong Kong from a critical feminist and decolonial perspective. We theorize political subjectivity as both collective and individual, as arising from particular historical and political junctures but also, importantly, through social relationships. We argue that political subjectivity must be understood in terms of the multiple processes through which it emerges and evolves in the interplay between history, politics, culture and interpersonal relationships. In so doing we advance an approach to political subjectivity as contextual and relational. While our discussion is based on the specific conditions facing Hong Kong activists, our mode of analysis may offer insights into other socio-political contexts

    Seeking Love and Justice Amid Hong Kong’s Contentious Politics

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    Hong Kong women activists’ understanding of love and justice has shaped, and been shaped, by their political engagement under changing circumstances through two phases of mass protest: in 2014 and 2019. This article is focused on the sentiments of love and justice and how they evolved over time, from the peaceful protest of the Umbrella Movement in 2014 to the violent confrontations of 2019 in the context of the rise of ethno-nationalism. This shift reflects a changed understanding of justice – revenge against China – and a specific version of passionate love for Hong Kong and protective love for their comrades. Women activists’ experiences offer insights into how a social movement has engaged women’s emotional energies in particular gendered ways, while persistently marginalising gender issues. In the aftermath of the movement, when protest was effectively banned by both COVID-19 restrictions and the 2020 National Security Law, these women’s emotions have found a new object of their fierce love for Hong Kong: the boy band Mirror, which has come to symbolise Hongkonger pride, belonging and resistance

    Interfacial Superconductivity and Zero Bias Peak in Quasi‐One‐Dimensional Bi2Te3/Fe1+yTe Heterostructure Nanostructures

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    Abstract Bismuth telluride/iron telluride (Bi2Te3/Fe1+yTe) heterostructures are known to exhibit interfacial superconductivity between two non‐superconducting materials: Fe1+yTe as the parent compound of Fe‐based superconducting materials and the topological insulator Bi2Te3. Here, a top‐down approach is presented starting from 2D heterostructures to fabricate 1D Bi2Te3/Fe1+yTe nanowires or narrow nanoribbons. It is demonstrated that the Bi2Te3/Fe1+yTe heterostructure remains intact in nanostructures of widths on the order of 100 nm and the interfacial superconductivity is preserved, as evidenced by electrical transport and Andreev reflection point contact spectroscopy experiments measured at the end of the nanowire. The differential conductance shows a similar superconducting twin‐gap structure as in 2D heterostructures, but with enhanced fluctuation effects due to the lower dimensionality. A zero‐bias conductance peak indicates the presence of an Andreev bound state and, given the involvement of the topological Bi2Te3 surface state, a possible topological nature of superconductivity is discussed with strong interplay with an emerging ferromagnetism due to the interstitial excess iron (Fe) in the Fe1+yTe layer, developing in parallel with superconductivity at low temperatures

    Characterization and seasonal variations of levoglucosan in fine particulate matter in xi’an, china

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    PM2.5 (particulate matter with an aerodynamic diameter &amp;lt;2.5 mu m) samples (n = 58) collected every sixth day in Xi'an, China, from 5 July 2008 to 27 June 2009 are analyzed for levoglucosan (1,6-anhydro-beta-d-glucopyranose) to evaluate the impacts of biomass combustion on ambient concentrations. Twenty-four-hour levoglucosan concentrations displayed clear summer minima and winter maxima that ranged from 46 to 1889 ng m(-3), with an average of 428 +/- 399 ng m(-3). Besides agricultural burning, biomass/biofuel combustion for household heating with straws and branches appears to be of regional importance during the heating season in northwestern China. Good correlations (0.70 &amp;lt; R &amp;lt; 0.91) were found between levoglucosan relative to water-soluble K+, Cl-, organic carbon (OC), elemental carbon (EC), and glyoxal. The highest levoglucosan/OC ratio of 2.3% was found in winter, followed by autumn (1.5%). Biomass burning contributed to 5.1-43.8% of OC (with an average of 17.6 +/- 8.4%). Implications: PM2.5 levoglucosan concentrations and the correlation between levoglucosan relative to other compounds during four seasons in Xi'an showed that the influence of biomass burning is maximum during the residential heating season (winter), although some important influences may be detected in spring (field preparation burnings) and autumn (corn stalks and wheat straw burning, fallen dead leaves burning) at Xi'an and surrounding areas. Household heating with biomass during winter was quite widespread in Guanzhong Plain. Therefore, the control of biomass/biofuel combustion could be an effective method to reduce pollutant emission on a regional scale
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