Assessment of diesel exhaust particulate exposure and surface characteristics in association with levels of oxidative stress biomarkers

Exposure to PM10 and PM2.5 (particulate matter with aerodynamic diameter smaller than 10 μm and 2.5 μm, respectively) is associated with a range of adverse health effects, including cancer, pulmonary and cardiovascular diseases. Surface characteristics (chemical reactivity, surface area) are considered of prime importance to understand the mechanisms which lead to harmful effects. A hypothetical mechanism to explain these adverse effects is the ability of components (organics, metal ions) adsorbed on these particles to generate Reactive Oxygen Species (ROS), and thereby to cause oxidative stress in biological systems (Donaldson et al., 2003). ROS can attack almost any cellular structure, like DNA or cellular membrane, leading to the formation of a wide variety of degradation products which can be used as a biomarker of oxidative stress. The aim of the present research project is to test whether there is a correlation between the exposure to Diesel Exhaust Particulate (DEP) and the oxidative stress status. For that purpose, a survey has been conducted in real occupational situations where workers were exposed to DEP (bus depots). Different exposure variables have been considered: - particulate number, size distribution and surface area (SMPS); - particulate mass - PM2.5 and PM4 (gravimetry); - elemental and organic carbon (coulometry); - total adsorbed heavy metals - iron, copper, manganese (atomic adsorption); - surface functional groups present on aerosols (Knudsen flow reactor). Several biomarkers of oxidative stress (8-hydroxy-2'-deoxyguanosine and several aldehydes) have been determined either in urine or serum of volunteers. Results obtained during the sampling campaign in several bus depots indicated that the occupational exposure to particulates in these places was rather low (40-50 μg/m3 for PM4). Bimodal size distributions were generally observed (5 μm and <1 μm). Surface characteristics of PM4 varied strongly, depending on the bus depot. They were usually characterized by high carbonyl and low acidic sites content. Among the different biomarkers which have been analyzed within the framework of this study, mean urinary levels of 8-hydroxy-2'-deoxyguanosine increased significantly (p<0.05) during two consecutive days of exposure for non-smoker workers. On the other hand, no statistically significant differences were observed for serum levels of hexanal, nonanal and 4- hydroxy-nonenal (p>0.05). Biomarkers levels will be compared to exposure variables to gain a better understanding of the relation between the particulate characteristics and the formation of ROS by-products. This project is financed by the Swiss State Secretariat for Education and Research. It is conducted within the framework of the COST Action 633 "Particulate Matter - Properties Related to Health Effects"

PENERAPAN MODEL PEMBELAJARAN LANGSUNG UNTUK MENINGKATKAN PROSES DAN HASIL BELAJAR PADA KOMPETENSI DASAR MELAKSANAKAN PROSEDUR KESEHATAN KESELAMATAN KERJA (K3) HYGINE SANITASI DI KELAS X SMKN 1 SOOKO MOJOKERTO

Model pengajaran langsung dirancang secara khusus untuk mengembangkan belajar siswa tentang pengetahuan prosedural dan deklaratif yang terstruktur dengan baik dan dapat diajarkan selangkah demi langkah (kardi dan nur, 2005:5). Pada kompetensi dasar melaksanakan prosedur K3 materi penataan area kerja dan perabot salon pembelajarannya dilakukan selangkah demi langkah. Penelitian ini bertujuan untuk : 1) mengetahui aktifitas guru dalam penerapan model pembelajaran langsung, 2) aktifitas siswa 3) hasil belajar siswa pada kompetensi dasar Kesehatan Keselamatan Kerja (K3) Hygine Sanitasi 4) respon siswa dalam penerapan model pembelajaran langsung. Jenis penelitian ini termasuk penelitian tindakan kelas yang menggunakan 2 siklus. Subyek penelitian kelas X Tata Kecantikan Rambut SMKN 1 Sooko Mojokerto berjumlah 36 siswa. Pengunpulan data yang digunakan berupa observasi, tes untuk mengetahui hasil belajar siswa, dan angket respon siswa terhadap model pembelajaran langsung. Hasil dari penelitian ini adalah sebagai berikut : hasil keseluruhan dari prosentase keterlaksanaan siklus I pada aktivitas guru sebesar (77,7%) ke siklus II (80%) mengalami peningkatan sebesar 2,3%. Aktivitas siswa pada aspek memperhatikan ketika guru mengkomunikasikan tujuan pembelajaran (Listening activity) siklus I sebesar (56%) kategori cukup ke siklus II (69%) kategori baik mengalami peningkatan sebesar 13%. Pada aspek siswa memperhatikan saat guru mengadakan evaluasi hasil praktik penataan ruang salon (visual activity) siklus I sebesar (33%) kategori buruk ke siklus II (69%) kategori baik terdapat peningkatan sebesar 36%. Hasil belajar siklus I masing-masing individu yang mendapatkan nilai ≥ 75 sebanyak 29 siswa dinyatakan tuntas dan ≤ 75 sebanyak 7 siswa dinyatakan tidak tuntas. Hasil nilai belajar kelas siklus I (78%) ke siklus II (86%) mengalami peningkatan 8%. Ketuntasan belajar secara klasikal siklus I (80%) ke siklus II (100%) mengalami peningkatan 20%. Hasil prosentase respon siswa yang mendapatkan prosentase tertinggi yaitu pada indikator saya merasa termotivasi ketika guru menunjukkan gambar-gambar tentang penataan ruang salon dan perabot salon yang nampak rapi dan indah melalui penggunaan model pengajaran langsung mendapatkan prosentase 91%. Kata kunci : model pengajaran langsung, prosedur K3. Abstract Direct instruction model specially designed to develop students learning about procedural knowledge and declarative with proper structured and able to taught step by step (Kardi and Nur, 2005: 5). On basic competence of performing work safety procedure the matter of work area arrangement and tools of salon, it learning conducted step by step. This research aimed to: 1) know teacher activities in the implementation of direct instruction, 2) students activity, 3) students learning achievement on basic competence of work safety procedure of hygiene sanitation, 4) students response toward the implementation of direct instruction model. Type of this research was classroom action research used 2 cycles. Subject of this research was class X hairstyling in SMKN 1 Sooko Mojokerto as many as 36 students. Data collecting method used was observation, test to know students learning achievement, and questionnaire of student response toward direct instruction model. Results of this research are following: totally percentage of realization of cycle I at teacher activities (77.7%) to the cycle II (80%) had improved 2.3%. Student activity at aspect of pay attention when teacher communicated learning goal (listening activity) at cycle I (56%) included in good enough category to the cycle II (69%) included in good category had improved 13%. At the aspect of students pay attention when teacher performing evaluation of room salon arrangement (visual activity) at cycle I (33%) included in poor category to the cycle II (69%) included in good category had improved 36%. Individual learning achievement at cycle I obtained score > 75 as many 29 students were completed and < 75 as many 7 students were not completed. Result of classical learning achievement at cycle I (78%) to the cycle II (86%) had improved 8%. Study completeness classically at cycle I (80%) to the cycle II (100%) had improved 20%. Percentage result of students response which have highest percentage was on indicator of “I motivated when teacher shows picture about salon room and tools arrangement seen nice and beautiful through the use of direct instruction model” obtained 91%. Keywords: direct instruction model, performing work safety procedure

Assessment of particulate exposure and surface characteristics in association with urinary levels of 8-hydroxy-2'-deoxyguanosine, considered as marker of oxidative stress

Epidemiological studies have demonstrated that exposure to fine particles is associated to adverse health effects, including cancer, respiratory and cardiovascular diseases. However, mechanisms by which particles induce health effects remain unclear. According to one of the most investigated hypotheses, particles cause adverse effects through the production of reactive oxygen species (ROS), which are very hazardous compounds able to attack directly biological structures, including the DNA strand or the lipid bilayer of the cells. If the defense mechanisms, constituted of antioxidants, are not able to counter ROS, then these compounds will cause in the body a range of oxidation reactions called "oxidative stress". The aim of the present research project was to better understand mechanisms by which exposure to fine particles induces oxidative stress. The first point of this project was to check whether exposure to high levels of fine particles is directly linked to oxidative stress, and whether this oxidative stress is accompanied by the activation of the defense mechanisms (antioxidants). The second point was to study the role played by the particle surface characteristics in the oxidative stress process. For that purpose, a study was conducted in bus depots with the participation of 40 mechanics. First, occupational exposure to particles (PM4) and to other pollutants (NOx, O3) was measured over a two-day period. Then, urine samples of mechanics were collected in order to measure levels of 8-hydroxy-2'-deoxyguanosine (8OHdG) and antioxidants. 8OHdG is a molecule formed by the oxidation of DNA and allowing to assess the oxidative stress status of the mechanics. Finally, particles were collected on filters, and functional groups located on the particle surface were analyzed in the laboratory using a Knudsen flow reactor. This technique allows not only to quantify functional groups on the particle surface, but also to measure the reaction kinetics. Results obtained during the field campaign in bus depots showed that mechanics were exposed to rather low levels of PM4 (20-85 μg/m3) and of pollutants (NOx: 100-1000 ppb; O3: <15 ppb). However, despite this low exposure, urinary levels of the oxidative stress biomarker (8OHdG) increased significantly for non-smoking workers over a two-day period of shift. This oxidative stress was accompanied by an increase of antioxidants, indicating the activation of defense mechanisms. On the other hand, the analysis of functional groups on the particle surface showed important differences, depending on the workplace, the date and the activities of workers. The particle surface contained simultaneously antagonistic functional groups which did not undergo internal reactions (such as acids and bases), and was usually characterized by a high density of carbonyl functions and a low density of acidic sites. Reaction kinetics measured using the Knudsen flow reactor pointed out fast reactions of oxidizable groups and slow reactions of acidic sites. Several exposure parameters were significantly correlated with the increase of the oxidative stress status: the presence of acidic sites, carbonyl functions and oxidizable groups on the particle surface; reaction kinetics of functional groups on the particle surface; particulate iron and copper concentrations; and NOx concentration

Mengkaji Pola Strategi Pengembangan UMKM dalam Menghadapi Perdagangan Bebas Kawasan MEA ( Masyarakat Ekonomi Asean ) Studi Kasus Kampung Batik Laweyan

ABSTRAK MENGKAJI POLA STRATEGI PENGEMBANGAN UMKM DALAM MENGHADAPI PERDAGANGAN BEBAS DALAM KAWASAN MEA (MASYARAKAT EKONOMI ASEAN) (STUDI KASUS KAMPUNG BATIK LAWEYAN) Alief Rakhman Setyanto F1113002 Kampung batik Laweyan merupakan sentra perkampungan pengusaha batik di Solo yang memiliki daya tarik sangat besar. Daya tarik meliputi kondisi sosial ekonomi, kondisi peninggalan budaya dan kondisi industri batiknya. Pada awalnya batik didominasi oleh desain batik tradisional. Setelah adanya kampung batik Laweyan, motif desain batik telah jauh berkembang dan moderen. UMKM batik Laweyan merupakan sentra produksi batik : baik itu batik cap, batik tulis dan batik konveksi akan tetapi UMKM batik Laweyan memiliki pola strategi pengembangan yang belum dikaji secara khusus Untuk mengkaji secara khusus perlu dilakukan penelitian yang mendalam pada umkm batik Laweyan, agar dapat mengetahui bagaimana pola strategi pengembangan yang digunakan UMKM batik Laweyan dapat menjaga eksistensi dan bertahan terhadap banyaknya barang – barang impor khusus batik masuk ke pasar domestik baik itu di wilayah kota Solo atau di wilayah luar kota Solo. Hasil pembahasan menjabarkan, perusahaan keluarga , hubungan industrial , strategi pengembangan dan modal sosial merupakan faktor kunci dalam pola strayegi pengembangan UMKM batik Laweyan dalam menghadapi perdagangan bebas kawasan MEA. Kata kunci : UMKM batik Laweyan, perusahaan keluarga, hubungan industrial,pola strategi pengembangan, modal sosia

Characterization of surface functional groups present on laboratory-generated and ambient aerosol particles by means of heterogeneous titration reactions

A Knudsen flow reactor has been used to quantify surface functional groups on aerosols collected in the field. This technique is based on a heterogeneous titration reaction between a probe gas and a specific functional group on the particle surface. In the first part of this work, the reactivity of different probe gases on laboratory-generated aerosols (limonene SOA, Pb(NO3)2, Cd(NO3)2) and diesel reference soot (SRM 2975) has been studied. Five probe gases have been selected for the quantitative determination of important functional groups: N(CH3)3 (for the titration of acidic sites), NH2OH (for carbonyl functions), CF3COOH and HCl (for basic sites of different strength), and O3 (for oxidizable groups). The second part describes a field campaign that has been undertaken in several bus depots in Switzerland, where ambient fine and ultrafine particles were collected on suitable filters and quantitatively investigated using the Knudsen flow reactor. Results point to important differences in the surface reactivity of ambient particles, depending on the sampling site and season. The particle surface appears to be multi-functional, with the simultaneous presence of antagonistic functional groups which do not undergo internal chemical reactions, such as acid-base neutralization. Results also indicate that the surface of ambient particles was characterized by a high density of carbonyl functions (reactivity towards NH2OH probe in the range 0.26-6 formal molecular monolayers) and a low density of acidic sites (reactivity towards N(CH3)3 probe in the range 0.01-0.20 formal molecular monolayer). Kinetic parameters point to fast redox reactions (uptake coefficient ?0&gt;10-3 for O3 probe) and slow acid-base reactions (?0&lt;10-4 for N(CH3)3 probe) on the particle surface. [Authors]]]> Vehicle Emissions ; Aerosols ; Particulate Matter ; Oxidative Stress ; Reactive Oxygen Species ; Biological Markers ; Surface Properties ; Occupational Exposure eng https://serval.unil.ch/resource/serval:BIB_B477DBDA9F10.P001/REF.pdf http://nbn-resolving.org/urn/resolver.pl?urn=urn:nbn:ch:serval-BIB_B477DBDA9F105 info:eu-repo/semantics/altIdentifier/urn/urn:nbn:ch:serval-BIB_B477DBDA9F105 info:eu-repo/semantics/acceptedVersion info:eu-repo/semantics/openAccess Copying allowed only for non-profit organizations https://serval.unil.ch/disclaimer application/pdf oai:serval.unil.ch:BIB_B478041350E0 2022-05-07T01:25:26Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_B478041350E0 Négocier pour pacifier. Ambassadeurs et médiateurs durant la guerre de Cent Ans Pibiri, Eva info:eu-repo/semantics/conferenceObject inproceedings La paix des Dames, volet 1, Entre politique, diplomatie et cérémoniel Dumont, Jonathan (ed.) Fragnart, Laure (ed.) Girault, Pierre-Gilles (ed.) Le Roux, Nicolas (ed.) fre oai:serval.unil.ch:BIB_B47924D65A2D 2022-05-07T01:25:26Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_B47924D65A2D Cancer du sein et obésité, une liaison dangereuse [Breast cancer and obesity, a dangerous relation]. info:eu-repo/semantics/altIdentifier/pmid/22734178 Zaman, K. Bodmer, A. Pralong, F. Castiglione-Gertsch, M. info:eu-repo/semantics/review article 2012 Revue Médicale Suisse, vol. 8, no. 342, pp. 1101-1104 info:eu-repo/semantics/altIdentifier/pissn/1660-9379 urn:issn:1660-9379 <![CDATA[Obesity is associated with different cancers including breast cancer, whose incidence is increased in postmenopausal women. It has an adverse impact on the prognosis of the patients, regardless of their menopausal status. The fact of receiving a systemic adjuvant therapy does not neutralize the prognostic role of obesity. Moderate weight loss after cancer diagnosis could improve the outcome of the patients, while a weight gain during treatment seems without significant effect. Currently available data are still too incomplete to justify systematic programs to lose weight with an oncologic therapeutic aim. However, it is worth to encourage and support our patients to have an optimal diet, physical activity, and to lose weight as promotion of general health

Sistem Pengendalian Internal Verifikasi Pembayaran Pembiayaan Barang dan Jasa Pada VQ Group Surabaya

The implementation of an internal control system in the form of verification of payment documents within a company is very important to support the company's performance. The purpose of this study was to find out the system and procedures for verifying payment of goods and services financing at the VQ Group Surabaya company. Every payment of goods and services must be documented verification to prevent dam and find procedure incompatibility. This research is descriptive qualitative. Data collection is done by interviewing relevant parties and methods of documentation of documents relating to verification of payments for financing goods and services. The results of the analysis of the research that has been conducted can be concluded that the VQ Group Surabaya company in verifying documents uses payment document verification procedures that have been set by the company, namely the form of formal verification and done manually. The problem that arises in the application of payment document verification is that there is an incomplete / loss of payment documents in the form of notes / invoices and the presence of writing errors (receipt numbers with fairly large numbers).Researchers suggest to maximize the process of verifying the payment of goods and services financing at VQ Group Surabaya, so it is better to further implement a computerized verification system and procedure to minimize any errors or human errors. Keywords: Internal Control System, Document Verification, Goods and Service

RANCANG BANGUN SISTEM INFORMASI PRAKTIK INDUSTRI DI JURUSAN TEKNIK INFORMATIKA UNESA BERBASIS WEBSITE

Skripsi/Tugas Akhir/PI adalah persyaratan untuk mendapatkan gelar Sarjana (S1) atau Diploma (D3) disetiap Perguruan Tinggi baik Negeri maupun Swasta yang ada di Indonesia. Setiap mahasiswa yang mengambil mata kuliah PI atau Praktik Industri harus melakukan bimbingan kepada dosen pembimbing masing-masing. Tujuan dari penelitian ini adalah membuat Sistem Informasi Praktik Industri diJurusan Teknik Informatika supaya memudahkan komunikasi mahasiswa dengan dosen pembimbing dalam bimbingan Praktik Indutri , dan memudahkan Mahasiswa untuk memulai dari awal Praktik industri/Magang sehingga sampai tahap akhir yaitu sidang PI yang dilaksanakan dijurusan Teknik Informatika. Adapun pendekatan yang digunakan dalam penelitian ini adalah pendekatan terstruktur yang menggunakan beberapa alat bantu dan teknik pengerjaan, seperti flowcart, flowmap, Data Flow Diagram ( DFD ), Conceptual Data Model (CDM), dan Pysical Data Model ( PDM ). Perangkat lunak yang digunakan dalam pengembangan sistem informasi akademik ( Praktik Industri ) ini adalah XAMPP, Sublime, DIA, dan Power Designer. Hasil akhir dari penelitian ini adalah program aplikasi berbasis web yang dapat memberikan gambaran lebih jelas mengenai Sistem Informasi Praktik Industri dan dosen penasehat akademik pada Universitas Negeri Surabaya (UNESA). Admin/Biro PI dapat menginput data mahasiswa, data dosen, data user. Mahasiswa dapat menginput daftar PI ,melihat daftar dosen pembimbing,Mahasiswa juga dapat mengunggah / upload bukti balasan dari perusahaan dan Persyaratan dari Fakultas , dan Mahasiswa dapat mendownload berita acara setelah memenuhi syarat PI yang ditentukan dijurusan Teknik Informatika. Dosen dapat menginput nilai mahasiswa yang dibimbing dan mahasiswa yang diuji,Dosen dapat melihat daftar Mahasiswa,nilai Mahasiswa yang dibimbing. Kata kunci : Sistem Informasi, Web,Praktik Industr

PENERAPAN MODEL PEMBELAJARAN LANGSUNG UNTUK MENINGKATKAN PROSES DAN HASIL BELAJAR PADA KOMPETENSI DASAR MELAKSANAKAN PROSEDUR KESEHATAN KESELAMATAN KERJA (K3) HYGINE SANITASI DI KELAS X SMKN 1 SOOKO MOJOKERTO

Model pengajaran langsung dirancang secara khusus untuk mengembangkan belajar siswa tentang pengetahuan prosedural dan deklaratif yang terstruktur dengan baik dan dapat diajarkan selangkah demi langkah (kardi dan nur, 2005:5). Pada kompetensi dasar melaksanakan prosedur K3 materi penataan area kerja dan perabot salon pembelajarannya dilakukan selangkah demi langkah. Penelitian ini bertujuan untuk : 1) mengetahui aktifitas guru dalam penerapan model pembelajaran langsung, 2) aktifitas siswa 3) hasil belajar siswa pada kompetensi dasar Kesehatan Keselamatan Kerja (K3) Hygine Sanitasi 4) respon siswa dalam penerapan model pembelajaran langsung. Jenis penelitian ini termasuk penelitian tindakan kelas yang menggunakan 2 siklus. Subyek penelitian kelas X Tata Kecantikan Rambut SMKN 1 Sooko Mojokerto berjumlah 36 siswa. Pengunpulan data yang digunakan berupa observasi, tes untuk mengetahui hasil belajar siswa, dan angket respon siswa terhadap model pembelajaran langsung. Hasil dari penelitian ini adalah sebagai berikut : hasil keseluruhan dari prosentase keterlaksanaan siklus I pada aktivitas guru sebesar (77,7%) ke siklus II (80%) mengalami peningkatan sebesar 2,3%. Aktivitas siswa pada aspek memperhatikan ketika guru mengkomunikasikan tujuan pembelajaran (Listening activity) siklus I sebesar (56%) kategori cukup ke siklus II (69%) kategori baik mengalami peningkatan sebesar 13%. Pada aspek siswa memperhatikan saat guru mengadakan evaluasi hasil praktik penataan ruang salon (visual activity) siklus I sebesar (33%) kategori buruk ke siklus II (69%) kategori baik terdapat peningkatan sebesar 36%. Hasil belajar siklus I masing-masing individu yang mendapatkan nilai ≥ 75 sebanyak 29 siswa dinyatakan tuntas dan ≤ 75 sebanyak 7 siswa dinyatakan tidak tuntas. Hasil nilai belajar kelas siklus I (78%) ke siklus II (86%) mengalami peningkatan 8%. Ketuntasan belajar secara klasikal siklus I (80%) ke siklus II (100%) mengalami peningkatan 20%. Hasil prosentase respon siswa yang mendapatkan prosentase tertinggi yaitu pada indikator saya merasa termotivasi ketika guru menunjukkan gambar-gambar tentang penataan ruang salon dan perabot salon yang nampak rapi dan indah melalui penggunaan model pengajaran langsung mendapatkan prosentase 91%. Kata kunci : model pengajaran langsung, prosedur K3. Abstract Direct instruction model specially designed to develop students learning about procedural knowledge and declarative with proper structured and able to taught step by step (Kardi and Nur, 2005: 5). On basic competence of performing work safety procedure the matter of work area arrangement and tools of salon, it learning conducted step by step. This research aimed to: 1) know teacher activities in the implementation of direct instruction, 2) students activity, 3) students learning achievement on basic competence of work safety procedure of hygiene sanitation, 4) students response toward the implementation of direct instruction model. Type of this research was classroom action research used 2 cycles. Subject of this research was class X hairstyling in SMKN 1 Sooko Mojokerto as many as 36 students. Data collecting method used was observation, test to know students learning achievement, and questionnaire of student response toward direct instruction model. Results of this research are following: totally percentage of realization of cycle I at teacher activities (77.7%) to the cycle II (80%) had improved 2.3%. Student activity at aspect of pay attention when teacher communicated learning goal (listening activity) at cycle I (56%) included in good enough category to the cycle II (69%) included in good category had improved 13%. At the aspect of students pay attention when teacher performing evaluation of room salon arrangement (visual activity) at cycle I (33%) included in poor category to the cycle II (69%) included in good category had improved 36%. Individual learning achievement at cycle I obtained score &gt; 75 as many 29 students were completed and &lt; 75 as many 7 students were not completed. Result of classical learning achievement at cycle I (78%) to the cycle II (86%) had improved 8%. Study completeness classically at cycle I (80%) to the cycle II (100%) had improved 20%. Percentage result of students response which have highest percentage was on indicator of “I motivated when teacher shows picture about salon room and tools arrangement seen nice and beautiful through the use of direct instruction model” obtained 91%. Keywords: direct instruction model, performing work safety procedure

Coating carbon nanotubes with a polystyrene-based polymer protects against pulmonary toxicity

BACKGROUND: carbon nanotubes (CNT) can have adverse effects on health. Therefore, minimizing the risk associated with CNT exposure is of crucial importance. The aim of this work was to evaluate if coating multi-walled CNT (MWCNT) with polymers could modify their toxicity, thus representing a useful strategy to decrease adverse health effects of CNT. We used industrially-produced MWCNT uncoated (NT1) or coated (50/50 wt%) with acid-based (NT2) or polystyrene-based (NT3) polymer, and exposed murine macrophages (RAW 264.7 cell line) or Balb/c mice by intratracheal administration. Biological experiments were performed both in vitro and in vivo, examining time- and dose-dependent effects of CNT, in terms of cytotoxicity, expression of genes and proteins related to oxidative stress, inflammation and tissue remodeling, cell and lung tissue morphology (optical and transmission electron microscopy), and bronchoalveolar lavage fluid content analysis.RESULTS: extensive physico-chemical characterization of MWCNT was performed, and showed, although similar dimensions for the 3 MWCNT, a much smaller specific surface area for NT2 and NT3 as compared to NT1 (54.1, 34 and 227.54 m(2)/g respectively), along with different surface characteristics. MWCNT-induced cytotoxicity, oxidative stress, and inflammation were increased by acid-based and decreased by polystyrene-based polymer coating both in vitro in murine macrophages and in vivo in lung of mice monitored for 6 months.CONCLUSIONS: these results demonstrate that coating CNT with polymers, without affecting their intrinsic structure, may constitute a useful strategy for decreasing CNT toxicity, and may hold promise for improving occupational safety and that of general the user