Desain Pit Penambangan Batubara Blok C pada PT. Intibuana Indah Selaras Kabupaten Nunukan Provinsi Kalimantan Utara

Desain pit adalah suatu kegiatan dalam merencanakan kegiatan produksi pada tambang dengan metode yang digunakan adalah tambang terbuka. Tujuan dari penelitian ini, untuk mendapatkandesain pit yang ideal, dengan mengunakan metode penampang sayatan, penyebaran batubara, cadangan overburden, cadangan batubara, geometri bench dan stripping ratio. Metode penelitian yang digunakan untuk pembuatan desain pit adalah program autocad 2012 . Adapun data – data yang yang diperhatikan dalam pembuatan desain pit meliputi kestabilan lereng ( lebar bench, tinggi bench, kemiringan lereng dan endapan batubara). Dari hasil pengolahan data, maka didapatkan luas bukaan pit 75,8763 Ha, dengan nilai stripping ratio 11 : 1 dan desain pit penambangan batubara dengan geometri bench tinggi yaitu 7 meter, lebar bench 3 – 4 meter dan kemiringan 65 o. Dimana desain pit penambangan sampai pada kedalam 2 m di permukaan laut

Migrant Ridesharing Drivers in San Francisco: A Case of Blocked Mobility?

Migrants have long turned to self-employment in host country labor markets due to not only racial and ethnic prejudices, but also issues of local language proficiency and lack of recognition of the academic degree from the sending country. The taxi industry, one particular occupational niche dominated by migrants, has long been studied by scholars. However, the industry has evolved into a newer and understudied form of transportation: ridesharing. This study argues that in the case of the ridesharing industry, drivers did indeed turn to the occupation because of factors such as insufficient English language level and foreign academic degrees, but also age and personal family matters. Participants were attracted to the ridesharing industry in large part because of the flexibility and level of compensation provided. As a whole, participants saw ridesharing as the best option available to them in an otherwise unsuitable labor market

Investigation of Thyroid Metabolism Diseases in Kütahya Region

Aim: The study was performed on the sera sent for other diagnostic purposes like thyroid function tests (thyroid-stimulating hormone, total triiodothyronine and total thyroxin) to the Laboratory of Kütahya Hıfzısıhha Institute. Material and Method: Patients visiting 13 health care centers province and districts of Kütahya province were included in this study. The study popula-tion consisted of 320 patients. Serum levels of cholesterol, trigliserid, HDL-cholesterol, LDL-cholesterol and lipid were measured. Results: The results of our study showed 250 individuals (78.12%) to be within normal ranges, 42 (13.12%) as hypothyroid, and 28 (8.75%) were hyperthyroid. Hypothyroid pa-tients had significantly higher levels of cholesterol, LDL-cholesterol, lipid and thyroid-stimulating hormone levels (p<0.05). While hyperthyroid patients had significantly lower levels of cholesterol, LDL-cholesterol and lipid levels when compared with patients with normal thyroid hormone levels (p<0.05); Thyroxin levels were significantly higher (p<0.05). Discussion: The results of this study showed that the population under study was at risk of goiter diseases

Application of vascular endothelial growth factor at different phases of intestinal ischemia/reperfusion: what are its effects on oxidative stress, inflammation and telomerase activity?

Background. Intestinal ischemic reperfusion injury (IRI) represents a great challenge in clinical practice, with high morbidity and mortality. Vascular endothelial growth factor (VEGF), asasignal protein, contributes tovasculogenesis and angiogenesis.Objectives. To evaluate the local effectiveness of VEGF following intestinal IRI and its relation with application time.Material and methods. Thirty Wistar albino rats were allocated to5 groups and underwent laparotomy. Thesuperior mesenteric arteries (SMA) were dissected in4 groups, while thecontrol group (GrC) underwent aresection ofsmall and large intestines. The VEGF group (Gr V) received VEGF following SMA dissection, with no further intervention, and theremaining 3 groups were subjected toischemia for 90min through occlusion ofSMA and reperfusion for 4h. Ischemic reperfusion group (Gr I/R) received no additional medication, while theremaining 2 groups received VEGF just before ischemia (Gr V+I/R) and during reperfusion (Gr I/R+V).Results. Both applications of VEGF caused decreases inplasma levels of interleukin6 (IL-6), tumor necrosis factor ? (TNF-?), intestinal malondialdehyde (MDA), oxidized glutathione, protein carbonyl levels, and increases inintestinal total glutathione and superoxide dismutase (SOD) levels. Telomerase activity, which disappeared for Gr I/R, was found to be elevated following both treatment groups. Similarly, the histopathological scores were found better for both treatment groups, but Gr V-I/R represented best outcomes.Conclusions. The findings of our study revealed that VEGF, applied either before ischemia or during reperfusion, iseffective onlocal damage following intestinal IRI. Byinterpreting thebiochemical analysis and histopathological findings, we conclude either treatment option to be considered according to the reason of intestinal IRI

Mitochondrial neurogastrointestinal encephalomyopathy: imaging and clinical findings in three patients

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare multisystemic autosomal recessive disorder characterized by ptosis, gastrointestinal dysmotility, cachexia, peripheral neuropathy, and leukoencephalopathy. We aimed to raise awareness in radiologists regarding this difficult-to-diagnose syndrome, which occurs in the presence of coexistent gastrointestinal dysmotility, cachexia, and neurologic manifestations. We report imaging and clinical findings of three patients with MNGIE. Our findings indicate that early diagnosis of the disease, together with the timely treatment of acute intercurrent illnesses, may retard the progression of MNGIE

Effect of polishing systems on fluoride release and surface roughness of different restorative materials

Secondary caries is an important factor in the replacement of the restorations, and it is thought that fluoride-releasing materials may prevent this problem. Furthermore, the fluoride release of the materials may be increased by polishing process. Available knowledge about the effect of polishing systems (PS) on the fluoride release of materials is limited. Therefore, this study was conducted to evaluate the effect of PS on the fluoride release of fluoride-containing materials. Restorative materials were divided into 6 groups: Fuji IX GP, Fuji II, Dyract XP, Beautifil II, Beautifil-Bulk, and Filtek Ultimate. Each group was also divided into four subgroups: Mylar strip, Sof-Lex Discs, Sof-Lex Diamond, and OneGloss. Fluoride release was determined using a fluoride ion-selective electrode. Surface roughness was evaluated with a profilometer. Two-way repeated measure and one- way ANOVA tests were used for statistical analysis. The initial rapid fluoride release was observed only in Fuji IX. The PS increased the fluoride release of Fuji IX and Fuji II and Dyract XP materials while reducing the fluoride release of resin-based materials. The highest surface roughness values were obtained with OneGloss. Further, a significant relationship between fluoride release and surface roughness was found. The polishing provides an increase in fluoride release, especially in glass-ionomer- based materials. This article revealed that there is a relationship between fluoride release and surface roughness. Proper PS must be chosen according to the material to provide the best clinical benefits in terms of fluoride release and surface roughness

Mechanical properties and repair bond strength of polymer-based CAD/CAM restorative materials

Information on the mechanical properties and repairability of computer-aided design/computer-aided manufacturing (CAD/CAM) blocks is scarce. Five CAD/CAM blocks with similar indications were evaluated, including four resin nanoceramics, one polymer-infiltrated ceramic network (PICN), and one feldspathic ceramic. CAD/CAM blocks were sectioned into 4 mm x 1.2 mm x 13 mm bars for flexural strength (FS), and 4 mm thick blocks were prepared for elastic modulus (EM), nanohardness (NH), and microshear bond strength (mu SBS) testing. FS of the CAD/CAM blocks was determined using a three-point bending test, whereas EM and NH values were measured using a nanoindenter. The reparability of the tested block materials was determined by the mu SBS test. One-way ANOVA was conducted for FS, EM, NH, and mu SBS followed by Tukey's pairwise comparison (alpha < 0.05). FS ranged from 115 to 207 MPa, EM from 8.21 to 44 GPa, NH from 0.76 to 7.24, and mu SBS from 24.9 to 30.6 MPa. The findings of the present study revealed that resin nanoceramic blocks exhibited higher FS values than PICN and feldspathic ceramic, and they have acceptable mechanical properties for the fabrication of single-unit restorations according to the ISO 6872:2008. Furthermore, all CAD/CAM blocks tested can be successfully repaired regarding their recommended repair protocol

Effect of polishing systems on fluoride release and surface roughness of different restorative materials

Secondary caries is an important factor in the replacement of the restorations, and it is thought that fluoride-releasing materials may prevent this problem. Furthermore, the fluoride release of the materials may be increased by polishing process. Available knowledge about the effect of polishing systems (PS) on the fluoride release of materials is limited. Therefore, this study was conducted to evaluate the effect of PS on the fluoride release of fluoride-containing materials. Restorative materials were divided into 6 groups: Fuji IX GP, Fuji II, Dyract XP, Beautifil II, Beautifil-Bulk, and Filtek Ultimate. Each group was also divided into four subgroups: Mylar strip, Sof-Lex Discs, Sof-Lex Diamond, and OneGloss. Fluoride release was determined using a fluoride ion-selective electrode. Surface roughness was evaluated with a profilometer. Two-way repeated measure and one-way ANOVA tests were used for statistical analysis. The initial rapid fluoride release was observed only in Fuji IX. The PS increased the fluoride release of Fuji IX and Fuji II and Dyract XP materials while reducing the fluoride release of resin-based materials. The highest surface roughness values were obtained with OneGloss. Further, a significant relationship between fluoride release and surface roughness was found. The polishing provides an increase in fluoride release, especially in glass-ionomer-based materials. This article revealed that there is a relationship between fluoride release and surface roughness. Proper PS must be chosen according to the material to provide the best clinical benefits in terms of fluoride release and surface roughness.La caries secundaria es un factor importante para el reemplazo de restauraciones y se considera que los materiales que liberan flúor pueden prevenir este problema. Además, la liberación de fluoruro de estos materiales podría incrementarse mediante el proceso de pulido. El conocimiento disponible sobre el efecto de los sistemas de pulido (SP) en la liberación de fluoruro de los materiales es limitado. Por lo tanto, este estudio se realizó para evaluar el efecto de los SP sobre la liberación de fluoruro de materiales que contienen fluoruro. Los materiales de restauración se dividieron en 6 grupos: Fuji IX GP, Fuji II, Dyract XP, Beautifil II, Beautifil-Bulk y Filtek Ultimate. Cada grupo también se dividió en cuatro subgrupos: Banda Mylar, Discos Sof-Lex, Sof-Lex Diamond y OneGloss. La liberación de fluoruro se determinó usando un electrodo selectivo de iones fluoruro. La rugosidad de la superficie se evaluó con un perfilómetro. Se utilizaron medidas repetidas bidireccionales y pruebas ANOVA de una vía para el análisis estadístico. La liberación inicial rápida de fluoruro se observó solo en Fuji IX. El SP aumentó la liberación de fluoruro de los materiales Fuji IX y Fuji II y Dyract XP al tiempo que redujo la liberación de fluoruro de los materiales a base de resina. Los valores más altos de rugosidad de la superficie se obtuvieron con OneGloss. Además, se encontró una relación significativa entre la liberación de fluoruro y la rugosidad de la superficie. El pulido proporciona un aumento en la liberación de fluoruro, especialmente en materiales a base de ionómero de vidrio. Este artículo reveló que existe una relación entre la liberación de fluoruro y la rugosidad de la superficie. El SP adecuado debe elegirse de acuerdo con el material para proporcionar los mejores beneficios clínicos en términos de liberación de fluoruro y rugosidad de la superficie

Effect of surface treatments and universal adhesive application on the microshear bond strength of CAD/CAM materials

PURPOSE. The aim of this study was to evaluate the microshear bond strength (mu SBS) of four computer-aided design/computer-aided manufacturing (CAD/CAM) blocks repaired with composite resin using three different surface treatment protocols. MATERIALS AND METHODS. Four different CAD/CAM blocks were used in this study: (1) flexible hybrid ceramic (FHC), (2) resin nanoceramic (RNC), (c) polymer infiltrated ceramic network (PICN) and (4) feldspar ceramic (FC). All groups were further divided into four subgroups according to surface treatment: control, hydrofluoric acid etching (HF), air-borne particle abrasion with aluminum oxide (AlO), and tribochemical silica coating (TSC). After surface treatments, silane was applied to half of the specimens. Then, a silane-containing universal adhesive was applied, and specimens were repaired with a composite, Next, mu SBS test was performed. Additional specimens were examined with a contact profilometer and scanning electron microscopy. The data were analyzed with ANOVA and Tukey tests. RESULTS. The findings revealed that silane application yielded higher mu SBS values (P<.05). All surface treatments were showed a significant increase in mu SBS values compared to the control (P<.05). For FHC and RNC, the most influential treatments were AlO and TSC (P<.05). CONCLUSION. Surface treatment is mandatory when the silane is not preferred, but the best bond strength values were obtained with the combination of surface treatment and silane application. HF provides improved bond strength when the ceramic content of material increases, whereas AlO and TSC gives improved bond strength when the composite content of material increases