Diversity and Abundance of Phytoplankton in the Coastal Waters of South Sulawesi

Phytoplankton are primary producers that can be used as seawater condition indicators. Certain phytoplankton can proliferate, causing harmful algal blooms (HABs). The coastal waters of South Sulawesi, Indonesia are under pressure from land-based processes and activities resulting in inputs of organic and inorganic materials. This study analysed phytoplankton diversity and abundance in coastal waters around South Sulawesi. Phytoplankton were sampled and seawater parameters (salinity, temperature, turbidity, pH, nitrate concentration) measured in-situ at six stations around seven major river estuaries in three seaways (Makassar Strait, Flores Sea, Gulf of Bone). Phytoplankton taxonomic composition, abundance and indices of diversity (H’), evenness (E), and dominance (D) were analysed. Phytoplankton from 31 species and three classes (Bacillariophyceae, Cyanophyceae, Dinophyceae) were identified. Phytoplankton abundance and community structure differed significantly between sites and seaways but were not significantly correlated with water quality parameters although Dinophyceae abundance correlated significantly with observed pollution levels. Phytoplankton abundance was strongly influenced by the Dinophyceae, especially Ceratium furca, a potential HAB species; Cyanophyceae had the strongest influence on species richness but least on community structure. C. furca abundance was strongly correlated negatively with species richness, H’ and E, and positively with D, indicating negative impacts of this species on phytoplankton communities

An influence of the SS316L powder particle shape to the densification of metal injection moulding (MIM) compact

Metal injection molding (MIM) has acquired increasing importance as a production technique for small, complex stainless steel components [1, 2]. Sintering is critical for determining the final quality of the parts produced by MIM. Because high sintered density is imperative for good mechanical properties and corrosion resistance, achieving full or near-full density has been a major objective of sintering [3]. Therefore, most research on 316L stainless steel sintering to date has focused on the sintering behavior of the molded parts especially for gas-atomised powder in argon environment [3-6]. An understanding of the factors influencing densification of stainless steels is important as over 50% of the injection molded and sintered components are made from stainless steel compositions [7]. In a metal injection molding (MIM) process, gas-atomised powder is generally used due to their high packing density and associated feedstock rheology. The sintered components exhibit mechanical and corrosion properties similar or superior to that of wrought material. Water-atomised powders in MIM can be economical and have an improvement in shape retention during debinding and sintering. However, their use comes with a penalty of lower powder loading and sintered density, with a corresponding degradation in the mechanical and corrosion properties. Studies reveal that injection molded and sintered components using water-atomised 316L stainless steel powders have a residual porosity of 3–5% for similar particle characteristics and sintering conditions as that of gas-atomised powders [5]. This article investigates a densification of SS316L gas and wateratomised compact sintered in high vacuum environment at temperature ranging from 1340 to 1400 °C

Implikatur Dan Kesantunan Positif Dalam Wacana Rapat Dinas Di Lingkungan Kelurahan Berlatar Belakang Budaya Jawa

Tujuan dari penelitian ini ada tiga, yaitu: (1) Mengidentifikasi wujud implikatur dalam wacana rapat dinas di lingkungan kelurahan berlatar belakang budaya Jawa. (2) Mengidentifikasi wujud kesantunan positif dalam wacana rapat dinas di lingkungan kelurahan berlatar belakang budaya Jawa. (3) Mengidentifikasi teknik dan strategi berdasarkan implikatur dan kesantunan positif dalam wacana rapat dinas di lingkungan kelurahan berlatar belakang budaya Jawa. Teknik pengumpulan data pada penelitian ini menggunakan teknik simak dan teknik rekam, catat. Metode analisis data yang digunakan dalam penelitian ini adalah metode padan intralingual dengan menghubungbandingkan unsur-unsur yang bersifat lingual dan padan ekstralingual dengan menghubungbandingkan unsur-unsur bahasa yang berupa bentuk itu dengan hal yang di luar bahasa. Hasil penelitian ini, dari 19 data dapat disimpulkan bahwa Terdapat empat wujud implikatur tuturan lurah dalam wacana rapat dinas di lingkungan kelurahan berlatar belakang budaya Jawa, yakni: berita, tanya, perintah, dan seru. Dari keempat wujud implikatur tuturan lurah tersebut lurah desa cenderung menggunakan wujud implikatur berita sebanyak (6 data), sedangkan lurah kota cenderung menggunakan wujud implikatur perintah sebanyak (8data). Selain itu terdapat delapan strategi kesantunan yang digunakan Lurah saat melakukan rapat dinas di lingkungan kelurahan, yakni dengan jumlah presentase Lurah kota lebih banyak menggunakan strategi kesantunan bila dibandingkan dengan Lurah desa, jumlah strategi kesantunan positif yang di gunakan oleh Lurah kota sebanyak enam strategi, yaitu (menunjukkan hal-hal yang dianggap mempunyai kesamaan melalui basa-basi (small talk) dan peranggapan (presupatision), menggunakan penanda identitas kelompok, melibatkan mitra tutur dalam aktivitas tuturan, menghindari ketidaksetujuan, memberikan tawaran, menggunakan kelakar atau lelucon). Sedangkan Lurah desa menggunakan tiga strategi kesantunan positif, yaitu (menunjukkan hal-hal yang dianggap mempunyai kesamaan melalui basa-basi (small talk) dan peranggapan (presupatision), menunjukkan keoptimisan, mengulang sebagian ujaran dari mitra tutur). Identifikasi teknik dan strategi yang digunakan dalam wacana rapat dinas di lingkungan kelurahan berlatar belakang budaya Jawa ditemukan satu strategi dan satu teknik yang digunakan yakni strategi langsung dan teknik langsung literal

Effect of Penalty Function Parameter in Objective Function of System Identification

The evaluation of an objective function for a particular model allows one to determine the optimality of a model structure with the aim of selecting an adequate model in system identification. Recently, an objective function was introduced that, besides evaluating predictive accuracy, includes a logarithmic penalty function to achieve a suitable balance between the former model’s characteristics and model parsimony. However, the parameter value in the penalty function was made arbitrarily. This paper presents a study on the effect of the penalty function parameter in model structure selection in system identification on a number of simulated models. The search was done using genetic algorithms. A representation of the sensitivity of the penalty function parameter value in model structure selection is given, along with a proposed mathematical function that defines it. A recommendation is made regarding how a suitable penalty function parameter value can be determined

Active and passive aperture coupled microstrip antenna design

Microstrip antennas has a few feeding technique applicable to them. One of them is the non-contacting feeds, which is the aperture-coupled feed techniques. The main mechanism of power transfer between its feed line and patch is the coupling mechanism through the aperture. This work is an effort to design, simulate, fabricate and measurement of passive and active rectangular patch with aperture coupled feed techniques. Simulation is being done using the Method of Moments (MoM). This is simulated in Microwave Office software. This design intends to focus on studying the differences in simulated and measured parameters of the antenna on its return loss, bandwidth and radiation pattern

Low Diastolic Blood Pressure Predicts Depression in End Stage Renal Disease Patients on Maintenance Haemodialysis

Aim: This study aimed to measure the prevalence and identify the predictors of depression in end stage renal disease (ESRD) patient on maintenance haemodialysis (HD). Methods: A 6-month cross-sectional study from December 2012 to May 2013 was conducted in nephrology unit, Hospital Sultanah Bahiyah and 3 private dialysis centres in Alor Setar, Kedah during the study period. Depression was assessed during the first hour of dialysis procedure in all participants using the Beck Depression Inventory (BDI). Results: A total of 91 patients were studied. The prevalence of depression was 19.8% with BDI cut-off score of 11. Lower diastolic blood pressure (P = 0.035) and presence of heart disease (P = 0.043) or stroke (P = 0.043) were found to be significantly associated with depression in ESRD patients on maintenance HD. None of the socio-demographic or laboratory parameters, including serum albumin, urea and hemoglobin, were signifícantly associated with depression. Conclusion: Depression is common and affecting about one-fifth of ESRD patients on HD. Hence, it is important to regularly assess the patients for depression giving particular attention to those with low diastolic blood pressure and co-morbid heart or cerebrovascular diseases

APLIKASI MODEL DINAMIK DAMPAK EUTROFIKASI DAN SEDIMENTASI BAGI PENGENDALIAN KERUSAKAN TERUMBU KARANG DI PERAIRAN SULAWESI SELATAN

The aplication of dynamic model to describe the effect of eutrophication and sedimentation on coral reefs damage in a wider scope. The trial were performed in two main areas of coral reefs in South Sulawesi, namely in Spermonde Archipelago and in Sembilan Archipelago in Bone Bay. Retrieval of data include measurements of water quality (nitrate and phosphate concentration) and the rate of sedimentation. While collecting of ecological data, namely macroalgae cover, coral reef cover, and species of herbivores and its abundance. Data was collected on monthly for 4 months at six stations/islands. The data was taken at two points on each island as replicates. Oceanographic data were taken every month, while the ecological data were taken at the end of the study. Nutrients concentration (nitrat and phosphat) and sedimentation rate were measured in laboratory. The result of the model test showed that the developed model is valid and broad-spectrum and therefore can be applied to other areas already impacted by eutrofi cation and sedimentation. The results of the execution of the model shows that all stations on the island leads Phase shift, namely the dominance of macroalgae cover in the future (about 2-4years in the future)

Detection of serum AFB1-lysine adduct in Malaysia and its association with liver and kidney functions

Aflatoxin is ubiquitously found in many foodstuffs and produced by Aspergillus species of fungi. Of many aflatoxin metabolites, AFB1 is classified by the International Agency for Research on Cancer (IARC) as group one carcinogen and linked to the development of hepatocellular carcinoma (HCC). The study on molecular biomarker of aflatoxin provides a better assessment on the extent of human exposure to aflatoxin. In Malaysia, the occurrences of aflatoxin-contaminated foods have been documented, but there is a lack of data on human exposure to aflatoxin. Hence, this study investigated the occurrence of AFB1-lysine adduct in serum samples and its association with liver and kidney functions. 5 ml fasting blood samples were collected from seventy-one subjects (n = 71) for the measurement of AFB1-lysine adduct, albumin, total bilirubin, AST (aspartate aminotransferase), ALT (alanine transaminase), ALP (alkaline phosphatase), GGT (gamma-glutamyl transpeptidase), creatinine and BUN (blood urea nitrogen). The AFB1-lysine adduct was detected in all serum samples (100% detection rate) with a mean of 6.85 ± 3.20 pg/mg albumin (range: 1.13–18.85 pg/mg albumin). Male subjects (mean: 8.03 ± 3.41 pg/mg albumin) had significantly higher adduct levels than female subjects (mean: 5.64 ± 2.46 pg/mg albumin) (p 6.85 pg/mg albumin) had significantly elevated level of total bilirubin (p < 0.01), GGT (p < 0.05) and creatinine (p < 0.01). Nevertheless, only the level of total bilirubin, (r = 0.347, p-value = 0.003) and creatinine (r = 0.318, p-value = 0.007) showed significant and positive correlation with the level of AFB1-lysine adduct. This study provides a valuable insight on human exposure to aflatoxin in Malaysia. Given that aflatoxin can pose serious problem to the health, intervention strategies should be implemented to limit/reduce human exposure to aflatoxin. Besides, a study with a big sample size should be warranted in order to assess aflatoxin exposure in the general population of Malaysia

Performance investigation of graphene based-nanofluids as a metalworking fluid for turning process

Most lubricants used for machining industry are mineral-based oil thus gives negative impact on environment and humans because of their toxicity and non-biodegradability. Therefore, vegetable-based oil has been taken as other initiatives to produce bio-based metalworking fluid (MWFs) especially from non-edible oil (jatropha oil). The aim of this study was to investigate the turning performance of nanofluids from modified jatropha based-oil (MJO) with the addition of graphene nanoparticles at various concentrations (0.01wt%, 0.025wt%, 0.05wt%). The performances of MJO based nanofluids were compared with synthetic ester (SE) as the benchmark oil in terms of cutting temperature, chip thickness and workpiece surface roughness. From the results, MJO + 0.025wt% graphene nanoparticles recorded the lowest cutting temperature, and chip thickness with smoother workpiece surface roughness compared to all samples. In conclusion, MJO + 0.025wt% exhibit superior machining performance and could be potential candidate as sustainable MWFs to replace mineral based oil for the machining processe