1,420 research outputs found

    Influence of spectral solar irradiance on the formation of new particles in the continental boundary layer

    No full text
    International audienceThe relationship between nucleation events and spectral solar irradiance was analysed using two years of data collected at the Station for Measuring Forest Ecosystem-Atmosphere Relations (SMEAR II) in Hyytiälä, Finland. We analysed the data in two different ways. In the first step we calculated ten nanometer average values from the irradiance measurements between 280 and 580 nm and explored if any special wavelengths groups showed higher values on event days compared to a spectral reference curve for all the days for 2 years or to reference curves for every month. The results indicated that short wavelength irradiance between 300 and 340 nm is higher on event days in winter (February and March) compared to the monthly reference graph but quantitative much smaller than in spring or summer. By building the ratio between the average values of different event classes and the yearly reference graph we obtained peaks between 1.17 and 1.6 in the short wavelength range (300--340 nm). In the next step we included number concentrations of particles between 3 and 10 nm and calculated correlation coefficients between the different wavelengths groups and the particles. The results were quite similar to those obtained previously; the highest correlation coefficients were reached for the spectral irradiance groups 3--5 (300--330 nm) with average values for the single event classes around 0.6 and a nearly linear decrease towards higher wavelengths groups by 30%. Both analyses indicate quite clearly that short wavelength irradiance between 300 and 330 or 340 nm is the most important solar spectral radiation for the formation of newly formed aerosols. In the end we introduce a photochemical mechanism as the probable responsible pathway by calculating the production rate of excited oxygen. This mechanism shows in which way short wavelength irradiance can influence the formation of new particles even though the absolute values are one to two magnitudes smaller compared to irradiance between 400 and 500 nm

    The part of the solar spectrum with the highest influence on the formation of SOA in the continental boundary layer

    Get PDF
    International audienceThe relationship between nucleation events and spectral solar irradiance was analysed using two years of data collected at the Station for Measuring Forest Ecosystem-Atmosphere Relations (SMEAR II) in Hyytiälä, Finland. We analysed the data in two different ways. In the first step we calculated ten nanometer average values from the irradiance measurements between 280 and 580 nm and explored if any special wavelengths groups showed higher values on event days compared to a spectral reference curve for all the days for 2 years or to reference curves for every month. The results indicated that short wavelength irradiance between 300 and 340 nm is higher on event days in winter (February and March) compared to the monthly reference graph but quantitative much smaller than in spring or summer. By building the ratio between the average values of different event classes and the yearly reference graph we obtained peaks between 1.17 and 1.6 in the short wavelength range (300--340 nm). In the next step we included number concentrations of particles between 3 and 10 nm and calculated correlation coefficients between the different wavelengths groups and the particles. The results were quite similar to those obtained previously; the highest correlation coefficients were reached for the spectral irradiance groups 3--5 (300--330 nm) with average values for the single event classes around 0.6 and a nearly linear decrease towards higher wavelengths groups by 30%. Both analyses indicate quite clearly that short wavelength irradiance between 300 and 330 or 340 nm is the most important solar spectral radiation for the formation of newly formed aerosols. In the end we introduce a photochemical mechanism as one possible pathway how short wavelength irradiance can influence the formation of SOA by calculating the production rate of excited oxygen. This mechanism shows in which way short wavelength irradiance can influence the formation of new particles even though the absolute values are one to two magnitudes smaller compared to irradiance between 400 and 500 nm

    QUORUM SENSING AND ITS ROLE IN ORAL BIOFILMS DEVELOPMENT

    Get PDF
    Quorum sensing systems has been identified as one of mechanism carried out by numerous Gram-positive and Gram-negative bacteria to coordinate virulence and biofilm development. Using quorum sensing bacterial colonies synchronize gene expression and phenotype change allowing them to protect their niche. The purpose of this review is to present a synopsis of the literature on bacterial quorum sensing and we highlight the role of specific signaling molecules that might be used as a target of inhibitor agent in dental preventive perspective

    IMPLEMENTASI EDUKASI MENGHINDARI KESALAHAN BERPIKIR PADA MAHASISWA MANAJEMEN

    Get PDF
    Dalam sebuah proses pembelajaran, kemampuan dalam pemecahan masalah merupakan hal yang sangat penting yang perlu dimiliki dan dikembangkan bahkan sebagai jantungnya pembelajaran. Pengabdian masyarakat dengan tema implementasi edukasi menghindari kesalahan berpikir pada mahasiswa manajemen ini bertujuan membantu mahasiswa manajemen dalam mengembangkan kemampuan berpikir, memecahkan masalah dan keterampilan intelektual untuk menghindari kesalahan berpikir. Metode yang digunakan dalam pelaksanaan kegiatan pengabdian masyarakat ini adalah secara daring. Pelaksanaan kegiatan dilaksanakan dalam satu tahap, yaitu melakukan  presentasi edukasi diskusi menghindari kesalahan berpikir. Mitra dalam kegiatan pengabdian masyarakat ini adalah mahasiswa jurusan Manajemen Fakultas Ekonomi dan Bisnis Universitas Trunojoyo Madura angkatan 2021. Dari pelaksanaan kegiatan didapatkan bahwa sebelum pelaksaaan kegiatan ini, tidak semua peserta telah mengenal dan menggunakan tentang kesalahan berpikir dalam perilaku hidup bermasyarakat sehari-hari dan dalam penyelesaian masalah yang dihadapi. Berdasarkan dari pelaksanaan kegiatan ini peserta dapat memahami dan berhasil mencoba menerapkan untuk menghindari kesalahan berpikir dalam kehidupan sehari-hari

    Analisis Buyback Saham Tanpa Rapat Umum Pemegang Saham di PT. Aneka Tambang (Studi Pada Surat Edaran Nomor 3/SEOJK.04/2020)

    Get PDF
    In early 2020, stock trading in Indonesia was under significant pressure, as indicated by the decline in the IHSG. This is due to the pressure and global economic slowdown due to the Covid-19 pandemic and weakening world oil prices. The purpose of this study was to find out how the effect of share buyback announcements without the RUPS on the response to the market at PT. Aneka Tambang Tbk. based on Surat Edaran OJK Nomor 3/SEOJK.04/2020. This research is structured with a quantitative method with a descriptive approach using secondary data types obtained from finance.yahoo.com and other relevant sources. This study will assess whether a significant difference is found before the announcement of the stock buyback and afterwards on the return, abnormal return, and trading volume activity of the stock. The results of the study stated that there was no significant difference before and after the announcement of the stock buyback on the return and abnormal return at PT. Aneka Tambang Tbk. However, a significant difference was found in the trading volume activity (TVA) before the announcement of the share buyback at PT. Aneka Tambang Tbk. and after

    Construction of Recombinant Plasmid PcDNA3.1/BMP-2 and Its Involvement in Differentiation of Human Dental Pulp-Derived Cells Into an Odontoblastic Lineage

    Full text link
    Experimental studies have shown that dental pulp tissue has potential to regenerate dentine in response to adverse stimuli, such as caries and associated operative procedures. However, the potential of dental pulp regeneration seems to be limited by regenerative capacity of the cell involved. In this study, we report the effect of transfection of a recombinant plasmid containing human BMP-2 gene in proliferation and differentiation of dental pulp tissue in vitro. The regenerative capacity was analyzed by ALP production and calcium content. Results showed that the transfected dental pulp cell was able to differentiate into the odontoblast phenotype, indicating the presence of odontoblast progentitor cells in dental pulp tissue

    Uji Efektifitas Beauveria Basianna Dan Bacillus Thuringiensis Terhadap Ulat Api (Setothosea Asigna Eeck, Lepidoptera, Limacodidae) Di Laboratorium

    Full text link
    Palm oil tree is the most productif than the other nabaty oil plant. Setothosea is the primaryleaf eaten on palm oil tree. Test Effectiveness of Bacillus thuringiensis and Beauveriabasianna Caterpillars Against Fire Setothosea asigna Eecke in laboratory. The research wasconducted at the Laboratory of Plant Pests Faculty of Agriculture, University of NorthSumatra, Medan with altitude ± 32 meters above sea level. The research method used is nonCompletely Randomized Design factorial. The parameters in the observed percentagemortality of larvae of the caterpillar is Setothosea asigna fire. The results show thepercentage of mortality of silkworm larvae using Beauveria basianna flames were highest intreatment by 100% I3 is the observation of the IV, percentage mortality of silkworm larvaeusing Bacillus thuringiensis flames were highest in I6 treatment was 100% in the observationof the IV

    Working Posture Evaluation of Clinical Student in Faculty of Dentistry University of Indonesia for the Scaling Task in Sitting Position in a Virtual Environment

    Full text link
    Musculoskeletal disorders (MSDs) are global issues in the dental profession. This research evaluated the MSDs risk caused by the sitting working posture of clinical students performing the task of scaling. The evaluation using the virtual environment approach shows risk of MSDs in the students’ upper extremities such as neck, shoulder, and trunk. Further simulation based on the ideal sitting working posture shows that ergonomic scaling could be achieved when the patient sits at a 15° angle. When scaling the 1st and 4th quadrant of the teeth, the 9 o’clock position is used. Hence, the 11 o’clock position is used when scaling the 2nd and 3rd quadrant

    The Income of Salt Farmers in Madura: an Explanation of Profit-Sharing System

    Get PDF
    This study aimed to determine and analyze the level of income generating of salt farmers in Madura. This research was conducted with a qualitative approach. The qualitative     approach in this study was to match empirical reality with the prevailing theory using descriptive methods. This research was located in the Sumenep Regency. Data collection techniques carried out by observation, interview, and documentation. Data analysis was performed descriptively-qualitatively. The results showed that the income of salt farmers in Madura was determined from the pattern of profit-sharing that had been chosen, namely the cost of salt production would be borne by landowners and sharecropper where the amount depended on the agreed pattern of profit-sharing. There were three pattern of profit-sharing between landowners and sharecropper in salt production, namely the pattern of dividing two (paron), the pattern of sharing for three (telon), and the pattern for five (leman). study aimed to determine and analyze the level of income generating of salt farmers in Madura. This research was conducted with a qualitative approach. The qualitative     approach in this study was to match empirical reality with the prevailing theory using descriptive methods. This research was located in the Sumenep Regency. Data collection techniques carried out by observation, interview, and documentation. Data analysis was performed descriptively-qualitatively. The results showed that the income of salt farmers in Madura was determined from the pattern of profit-sharing that had been chosen, namely the cost of salt production would be borne by landowners and sharecropper where the amount depended on the agreed pattern of profit-sharing. There were three pattern of profit-sharing between landowners and sharecropper in salt production, namely the pattern of dividing two (paron), the pattern of sharing for three (telon), and the pattern for five (leman)

    ANALYSIS OF THE POTENTIAL OF STREPTOCOCCUS SALIVARIUS ISOLATED FROM THE SALIVA AND TONGUE DORSUM TO INHIBIT THE GROWTH OF FUSOBACTERIUM NUCLEATUM

    Get PDF
    Objective: Analyzing the potential of S. salivarius isolated from the saliva and tongue dorsum of adults to inhibit the growth of Fusobacteriumnucleatum.Methods: Polymerase chain reaction, deferred antagonism test, and well-diffused agar test.Results: Inhibition of the growth F. nucleatum by S. salivarius isolated from the tongue dorsum (p>0.05). No inhibition to the growth of F. nucleatumby S. salivarius isolated from the saliva. No inhibition to the growth of F. nucleatum by the protein produced by S. salivarius.Conclusions: The growth of F. nucleatum was not inhibited by S. salivarius isolated from the saliva but by S. salivarius isolated from the dorsum of thetongue
    corecore