Aerodynamic Characterization of a Wells Turbine Under Bi-Directional Airflow

Abstract This work deals with the experimental study of the flow in a Wells turbine submitted to an unsteady and bi-directional airflow. The investigations were carried out on an experimental set-up that can simulate the real operating conditions of a wave energy conversion device using a two-dimensional hot-wire anemometer probe to analyse the flow field upstream and downstream of the turbine during its non-stationary operation. In addition to local measurements, the position of the piston that simulates the wave motion, the driving torque and the turbine rotational speed were also measured. These surveys allowed determination of the turbine instantaneous performances by analysing the aerodynamic flow characteristic at mid-span in the blade-to-blade plane downstream of the rotor. The flow distribution was obtained for the phase of inflow and outflow at different values of rotational speed which was kept constant during data acquisition. The results showed asymmetric behaviour for the two phases of intake and exhaust stroke of the piston and during acceleration and deceleration of the flow. The real entity of the hysteresis phenomenon that arose during the phases of acceleration and deceleration of the unsteady flow was evaluated considering velocity distribution in close proximity of the rotor

Sambiloto (Andrographis paniculata Nees.) for reducing aflatoxsins contamination in commercial chicken feed

Indonesian climate condition is suitable for growing of mold such as Aspergillus flavus. The mold grown in feed and feed ingredients cause aflatoxins contamination of the feed. Sambiloto has been reported to reduce the growth of Aspergillus flavus and aflatoxins production in feed isolate. The aim of the study was to find the used of sambiloto in reducing aflatoxins contamination in commercial chicken feed. The feed was homogenously mixed then divided into 4 groups with 3 replicates. The samples were treated with sambiloto 0.04%, 0.08% and 0.16% respectively into the feed, except for the control feed sambiloto was not added. Into these feed 4 ml of Aspergillus flavus suspension was also added. Then the feed in each group was incubated at room temperature for 10 days. Samples were collected from each group at days 0, 5 and 10 of incubation times for aflatoxins analysis. Samples were extracted and aflatoxins were detected by High Performance Liquid Chromatography (HPLC). Observation results indicated that sambiloto concentration of 0.16% in feed can inhibit the total aflatoxins production of 16.46% and gave the inhibitation percentage of aflatoxin B1 of 45.39%. Statistical test showed that the used of sambiloto in feed for 5 days incubation times gave significant result in reducing aflatoxins production. However the 10 days incubation times of the feed with sambiloto gave in significant result. It is suggested that to get optimum inhibition of aflatoxins production, sambiloto added in feed should be higher than 0.16%.   Key words : Feed, aflatoxin, sambilot

Karakteristik dan Analisis Pendapatan Pekerja Sektor Informal di Sekitar Pasar Kembang, Sosromenduran, Gedongtengen, Yogyakarta

Kawasan sekitar lokalisasi Pasar Kembang menjadi salah satu tempat aktivitas perekonomian pada sektor informal yang cukup tinggi di Yogyakarta. Penelitian ini bertujuan untuk mengetahui karakteristik pekerja sektor informal serta menganalisis faktor – faktor yang memengaruhi pendapatan pekerja sektor informal. Metode kualitatif dan kuantitatif digunakan untuk memperoleh data desktriptif serta menggunakan analisis korelasi dan regresi untuk mengetahui faktor – faktor apa saja yang berpengaruh atau memiliki hubungan terhadap pendapatan. Hasil penelitian menunjukkan karakteristik pekerja sektor informal di sekitar Pasar Kembang didominasi oleh pria, usia produktif, pendikan SMA ke atas, tanggungan 1 orang, jenis usaha kios/warung, jam kerja rata-rata 10 jam, lama kerja >3 tahun, modal ratusan ribu hingga jutaan, dan pendapatan yang masih rendah (<UMK).  Hasil analisis uji korelasi dalam penelitian ini menunjukkan adanya hubungan yang signifikan antara jam kerja dengan jumlah pendapatan. Sedangkan tingkat pendidikan, jumlah modal, lama kerja, dan usia teruji tidak berhubungan. Hal ini menunjukkan bahwa semakin lama jam kerja maka semakin tinggi pula pendapatan. Namun, tingkat pendidikan, jumlah modal, lama kerja, dan usia tidak menunjukkan pengaruh yang signifikan. Hal ini sesuai dengan teori bahwa tingkat pendidikan serta modal tidak terlalu berpengaruh dalam sektor informal

Evaluation of an automatic HPLC analyser for thalassemia and haemoglobin variants screening

In this paper the authors report the evolution of a new automatic HPLC analyser for screening haemoglobinopathies. HbA2 and F determinations are accurate and reproducible. The analysis time is short (6.5 min) and there is a good separation between the HbA2 values of β-thalassemia carriers from normals and α-thalassemia carriers, with no overlap between these groups. In addition, the system is also able to detect and quantitate most of the haemoglobin variants, particularly those (HbS, HbC, HbE and Hb Lepore) able to interact with β-thalassemia and could make haemoglobin electrophoresis unnecessary in all samples. The ease of operation and the limited technical work make this system especially suitable for laboratories with a high workload and allow the cost of screening to be reduced

Collagen-Binding Peptidoglycans Inhibit MMP Mediated Collagen Degradation and Reduce Dermal Scarring

Scarring of the skin is a large unmet clinical problem that is of high patient concern and impact. Wound healing is complex and involves numerous pathways that are highly orchestrated, leaving the skin sealed, but with abnormal organization and composition of tissue components, namely collagen and proteoglycans, that are then remodeled over time. To improve healing and reduce or eliminate scarring, more rapid restoration of healthy tissue composition and organization offers a unique approach for development of new therapeutics. A synthetic collagen-binding peptidoglycan has been developed that inhibits matrix metalloproteinase-1 and 13 (MMP-1 and MMP-13) mediated collagen degradation. We investigated the synthetic peptidoglycan in a rat incisional model in which a single dose was delivered in a hyaluronic acid (HA) vehicle at the time of surgery prior to wound closure. The peptidoglycan treatment resulted in a significant reduction in scar tissue at 21 days as measured by histology and visual analysis. Improved collagen architecture of the treated wounds was demonstrated by increased tensile strength and transmission electron microscopy (TEM) analysis of collagen fibril diameters compared to untreated and HA controls. The peptidoglycan's mechanism of action includes masking existing collagen and inhibiting MMP-mediated collagen degradation while modulating collagen organization. The peptidoglycan can be synthesized at low cost with unique design control, and together with demonstrated preclinical efficacy in reducing scarring, warrants further investigation for dermal wound healing

The right place for me: a moderated mediation model to explain involvement of employees aged over 50 years

Over the past decades, employment rates of older workers in most Western countries have rapidly increased. Hence, there is a growing interest in identifying the organizational dimensions that might impact the psychosocial adjustment of workers aged over 50 years. This study focuses on perceived organizational support (POS) and identity‐related measures (identification and authenticity) as key organizational components for workers at this stage of life. Furthermore, in the relationships discussed, we explore the moderating role of perceived age discrimination. In an ample sample of older workers (N = 4,563, aged 50–66 years), a moderated mediational model was tested where older workers' involvement was associated to POS. In the model, this relationship was mediated by organizational identification and authenticity, and the association between POS, identity‐related measures, and involvement was moderated by age‐based discrimination. Results showed that POS is associated with organizational involvement via organizational identification and authenticity and that high level of age discrimination decreased the positive association between POS, organizational identification, authenticity, and involvement

Wells turbine for wave energy conversion : a review

In the past twenty years, the use of wave energy systems has significantly increased, generally depending on the oscillating water column (OWC) concept. Wells turbine is one of the most efficient OWC technologies. This article provides an updated and a comprehensive account of the state of the art research on Wells turbine. Hence, it draws a roadmap for the contemporary challenges which may hinder future reliance on such systems in the renewable energy sector. In particular, the article is concerned with the research directions and methodologies which aim at enhancing the performance and efficiency of Wells turbine. The article also provides a thorough discussion of the use of computational fluid dynamics (CFD) for performance modeling and design optimization of Wells turbine. It is found that a numerical model using the CFD code can be employed successfully to calculate the performance characteristics of W-T as well as other experimental and analytical methods. The increase of research papers about CFD, especially in the last five years, indicates that there is a trend that considerably depends on the CFD method

ON THE RELATIONSHIP BETWEEN MULTIPLE SOCIAL IDENTITIES CONFIGURATIONS AND PSYCHOLOGICAL ADJUSTMENT

Recentemente è cresciuto l'interesse tra i ricercatori di psicologia applicata nel misurare l'associazione tra identità sociali multiple e adattamento psicologico. Attingendo dal Social Identity Approach, dall'Intersectionality Theory e dalle teorie sull'integrazione identitaria, in questa raccolta di studi viene analizzata la relazione tra identità multiple e adattamento psicologico adottando diversi metodi.Recently, there has been increased interest among applied psychological researchers in measuring the associations between intersecting social identities and individual psychological adjustment. Drawing upon social identity approach, intersectionality, identity integration theories and research, in this collection of studies we analyze the relationship between multiple identities and psychological outcomes adopting different methods