723 research outputs found

    Kesuburan Perairan Ditinjau dari Kandungan Klorofil-a Fitoplankton : Studi Kasus di Sungai Wedung, Demak

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    Perairan Sungai Wedung merupakan ekosistem pesisir yang banyak dimanfaatkan untuk berbagai kegiatan manusia. Hal tersebut tentunya berpengaruh terhadap kesuburan perairan Sungai Wedung. Kesuburan di perairan tersebut dipengaruhi oleh plankton, faktor kimia, fisika dan juga kandungan Klorofil-A. Pengukuran kandungan klorofil-a fitoplankton merupakan salah satu alat pengukuran kesuburan suatu perairan. Klorofil-a fitoplankton adalah suatu pigmen aktif dalam sel tumbuhan yang mempunyai peran penting dalam berlangsungnya proses fotosintesis perairan. Penelitian dilakukan pada bulan April – Mei 2013 di Sungai Wedung, Demak bertujuan untuk mengetahui aktivitas manusia terhadap sebaran klorofil-a, keterkaitan antara klorofil-a dan kelimpahan fitoplankton dan tingkat kesuburan perairan berdasarkan kandungan klorofil-a fitoplankton. Metode yang digunakan adalah metode studi kasus dengan teknik pengambilan sampel menggunakan metode “Sample Survey Method”. Hasil penelitian menunjukkan bahwa hasil analisis data klorofil menggunakan metode anova tersarang (nested anova) diperoleh nilai P untuk stasiun cukup besar sehingga tidak memberikan perbedaan yang nyata pada taraf kepercayaan 95 %. Akan tetapi perbedaan akan nyata pada taraf 90%. Hubungan antara klorofil-a dengan kelimpahan fitoplankton secara linear menunjukkan nilai keeratan yang tinggi dengan nilai koefisien korelasi sebesar 0,93 dan koefisien determinasi sebesar 0,8633 dimana 86% klorofil-a dipengaruhi oleh kelimpahan fitoplankton. Berdasarkan nilai rata-rata klorofil-a yang diperoleh sebesar 1,039863 mg/l dapat disimpulkan bahwa perairan Sungai Wedung tergolong kedalam perairan yang bersifat oligotrofik

    Using olive mill wastewate to improve performance in producing electricity from domestic wastewater by using single-chamber microbial fuel cell

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    Improving electricity generation from wastewater (DW) by using olive mill wastewater (OMW) was evaluated using single-chamber microbial fuel cells (MFC). Doing so single-chambers air cathode MFCs with platinum anode were fed with domestic wastewater (DW) alone and mixed with OMW at the ratio of 14:1 (w/w). MFCs fed with DW + OMW gave 0.38 V at 1 kO, while power density from polarization curve was of 124.6mW m 2. The process allowed a total reduction of TCOD and BOD5 of 60% and 69%, respectively, recovering the 29% of the coulombic efficiency. The maximum voltage obtained from MFC fed with DW + OMW was 2.9 times higher than that of cell fed with DW. DNA-fingerprinting showed high bacterial diversity for both experiments and the presence on anodes of exoelectrogenic bacteria, such as Geobacter spp. Electrodes selected peculiar consortia and, in particular, anodes of both experiments showed a similar specialization of microbial communities independently by feeding used

    Humerus shaft fracture complicated by radial nerve palsy: Is surgical exploration necessary?

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    Fractures of the humerus shaft often are complicated by radial nerve palsy. Controversy still exists in the treatment that includes clinical observation and eventually late surgical exploration or early surgical exploration. Algorithms have been proposed to provide recommendations with regard to management of the injuries. However, advantages and disadvantages are associated with each of these algorithms. The aim of this study was to analyze the indications of each treatment options and facilitate the surgeon in choosing the conduct for each lesion, proposing our own algorithm

    Selenium and Other Trace Elements in the Etiology of Parkinson's Disease: A Systematic Review and Meta-Analysis of Case-Control Studies

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    Background: Parkinson's disease (PD) is the most common neurodegenerative disease after Alzheimer's dementia. Whereas the exact etiology of PD remains unknown, risk of developing PD seems to be related to a combination of genetic and environmental factors. This also includes abnormal exposure to trace elements of nutritional and toxicological interest. Objectives: In this systematic review and meta-Analysis, we summarized the results of case-control studies comparing levels of selenium, copper, iron, and zinc in PD patients and controls in either blood (whole blood, serum/plasma) or cerebrospinal fluid (CSF). Methods: We performed a systematic PubMed search selecting studies reporting trace element levels in different specimens of patients and controls. We performed a meta-Analysis using a random-effect model to compute the weighted mean differences (WMD) and corresponding 95% CI of selenium, copper, iron, and zinc levels in the blood or CSF of patients and their matched controls. Results: We retrieved 56 papers reporting data for selenium (cases/controls: 588/721), copper (2,190/2,522), iron (2,956/3,469), and zinc (1,798/1,913) contents in CSF and blood. Cases showed considerably higher levels of selenium in CSF compared with controls (+51.6%; WMD 5.49; 95% CI 2.82 to 8.15), while levels in serum were similar (-0.2%; WMD-0.22; 95% CI-8.05 to 7.62). For copper, cases showed slightly higher levels in CSF and slightly lower concentrations in serum (+4.5%; WMD 1.87; 95% CI-3.59 to 7.33, and-4.5%; WMD-42.79; 95% CI-134.35 to 48.76, respectively). A slight increase was also found for CSF iron-levels (+9.5%; WMD 9.92; 1.23 to 18.61), while levels were-decreased in serum/plasma (-5.7%; WMD-58.19; 95% CI-106.49 to-9.89) and whole blood (-10.8%; WMD-95.69; 95% CI-157.73 to-33.65). Conversely, for zinc cases exhibited lower levels both in CSF (-10.8%; WMD-7.34; 95% CI-14.82 to 0.14) and serum/plasma (-7.5%; WMD-79.93; 95% CI-143.80 to-16.06). A longer duration of the disease tends to be associated with overall lower trace element levels in either CSF or blood. Conclusions: Due to the study findings and the greater relevance of the CSF compartment compared with the circulating peripheral ones, this meta-Analysis suggests that overexposure in the central nervous system to selenium, and possibly to copper and iron, may be a risk factor of the disease, while zinc might have a protective-effect

    Selenium and other trace elements in the etiology of Parkinson’s disease: a systematic review and meta-analysis of case-control studies

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    .INTRODUCTION Parkinson’s disease (PD) is a neurodegenerative illness recognised as the most common neurological disorder after Alzheimer’s dementia. Whereas the exact PD etiology remains unknown, risk of developing PD seems to be related to an interrelation of genetic and environmental factors, including also altered exposure to trace elements. In this systematic review and meta-analysis, we updated and summarized the results of epidemiologic case-control studies comparing levels of selenium, copper, iron and zinc in PD patients with healthy subjects in either blood (as whole blood, serum or plasma) and cerebrospinal fluid (CSF). MATERIALS AND METHODS We performed a systematic PubMed search and we included in our assessment only studies reporting demographic and disease-related characteristics, as well as trace element levels in different specimens (whole blood, serum/plasma and CSF). We then performed a meta-analysis of mean differences of trace element levels between cases and controls, using a random-effect model computing the weighted mean differences (WMD) and corresponding 95% confidence intervals (CI) to assess the association between serum/plasma, whole blood, CSF and selenium, copper, iron and zinc with Parkinson’s disease. RESULTS We retrieved 55 papers reporting data for selenium (588 cases and 721 controls), copper (2190 and 2522), iron (2843 and 3434), and zinc (1798 and 1913). Cases showed higher levels of selenium in CSF compared with controls (WMD=5.49; 95%CI 2.82 to 8.15), while levels in serum were similar (WMD=-0.22; -8.05 to 7.62). For copper cases showed higher levels in CSF and lower in serum compared to controls (WMD=1.87; -3.59 to 7.33, and -42.79, -134.35 to 48.76 respectively). Same results were found for iron in CSF (WMD=6.54; -1.97 to 15.04) and in serum/plasma (WMD=-58.19; -106.49 to -9.89 and whole blood (WMD=-95.69; 157.73 to -33.65). On the converse, cases had lower levels of zinc both in CSF (WMD=-7.34; -14.82 to 0.14) and serum/plasma (WMD=-79.93; -143.80 to -16.06). CONCLUSIONS Results of this systematic review and meta-analysis suggests that overexposure to environmental selenium, copper and iron may be risk factors for PD onset or progression. Alternatively, some variation in levels of these trace elements may occur as a consequence of the disease. Considering the burden of PD in the world population, further investigation of trace element exposure in this disease is therefore warranted, especially to plan possible prevention measures
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