Kajian Potensi Energi Arus Laut Sebagai Energi Alternatif Untuk Pembangkit Listrik Di Perarian Selat Lembeh, Sulawesi Utara

Kebutuhan akan energi listrik terus mengalami peningkatan dan sumber energi utamanya adalah energi konvensional yang ketersediannya terbatas di alam, untuk itu diperlukan adanya pencarian sumber energi lain yang terbarukan. Selat Lembeh merupakan wilayah perairan sempit yang berada di antara Laut Maluku yang dipengaruhi oleh massa air dari Pasifik dan Laut Sulawesi yang dipengaruhi oleh massa air dari Hindia. Penelitian ini bertujuan untuk mengetahui karakteristik arus laut serta mengetahui potensi arus laut sebagai sumber energi alternatif pembangkit listrik. Pengolahan data terdiri dari analisa data arus dan pasang surut, pemodelan numerik, dan menghitung estimasi rapat daya. Penelitian ini menggunakan metode kuantitatif dan penentuan lokasi dengan sampling area. Berdasarkan hasil penelitian, rapat daya terbesar yang dihasilkan yaitu pada musim barat, sebesar 120,02 kW/m2

Rows show examples representing the main phenotypic categories recovered from the central (RP2) neuron dendrite misexpression screen

Left and centre columns: confocal images (maximal Z-projections) of RP2 neurons at 25–31 hours AEL, visualised with . Control RP2 neuron with brackets indicating the dendritic tree. Control RP2 neuron in the context of a set of axon tracts visualised by anti-FasciclinII staining (magenta), with arrowheads pointing from top to bottom to the lateral, intermediate and medial FasciclinII tracts and the midline indicated by a dotted line. Dendrites between the lateral and central intermediate Fasciclin II fascicle are defined as 'lateral'; dendrites located between the central intermediate fascicle and the midline as 'medial'; the same applies to (o,p). Same neuron as in (b) but with sectors of its dendritic tree pseudo-coloured to highlight branches targeted to anterior lateral (magenta), anterior medial (yellow) and posterior lateral (cyan) regions. Anterior is left and the ventral midline is down. Experimental cells: misexpression lines are indicated in the bottom right-hand corner of each panel. Right column: quantifications of the dendritic phenotypes shown in the left and central columns. As illustrated in (f), both dendritic tree length and number of branching events are reduced in the 'Growth' and 'Branching' categories. 'Branching' phenotypes have trees with an anterior-posterior extent comparable to controls (Additional file ) but have an altered pattern of branching: fewer branching events and more segments that are longer (>5 μm). *< 0.01, **< 0.005, -test, N = 5. Error bars indicate the standard error. Arrows in (b,o,p) point to medial branches present in controls (b) and absent/reduced in experiments (o,p). Black asterisks in (e,p) indicate the cell body of the contralateral RP2 neuron. Scale bar: 10 μm.<p><b>Copyright information:</b></p><p>Taken from "Identification of genes influencing dendrite morphogenesis in developing peripheral sensory and central motor neurons"</p><p>http://www.neuraldevelopment.com/content/3/1/16</p><p>Neural Development 2008;3():16-16.</p><p>Published online 10 Jul 2008</p><p>PMCID:PMC2503983.</p><p></p

Control and experiments showing confocal images (maximal Z-projections) of RP2 neurons at 25–31 hours AEL, visualised with (green) in the context of a set of axon tracts visualised by anti-FasciclinII staining (magenta)

Dendrites between the lateral and central intermediate Fasciclin II fascicle are defined as 'lateral'; dendrites located between the central intermediate fascicle and the midline as 'medial'. Misexpression lines are indicated in the bottom left hand corner of each panel. Misexpression of () leads to aberrant midline crossing of dendritic branches (arrowhead), though no apparent increase of dendrites targeted towards the midline between the intermediate and medial FascilinII tracts. The high variability in phenotype is partly due to the varying lengths the dendritic tree mis-routed across the ventral midline. Misexpression of () causes increased targeting of dendrites into the medial neuropile (arrowhead). Black asterisk indicates the cell body of the contralateral RP2 neuron. Ventral (d) and lateral (d') views of stage 13 embryos driving expression of GSd433 with and stained by in hybridisation using an anti-sense probe against . The staining shows the segmentally repeated stripes characteristic for . The reaction had to be terminated before the endogenous expression pattern appeared (see Additional file ) due the high levels of expression. Misexpression of by GSd433 (e) or (f) leads to a reduction to near absence () of branches innervating the medial neuropile (arrowheads), and some dendritic branches positioned aberrantly lateral of the lateral Fasciclin II axon tract (arrows). Quantification showing ratios of medial/lateral dendrites; *= 0.04, **< 0.001, -test, N = 5; error bars indicate the standard error. Anterior is left. Scale bars: (a-c,e,f) = 10 μm; (d,d') = 140 μm.<p><b>Copyright information:</b></p><p>Taken from "Identification of genes influencing dendrite morphogenesis in developing peripheral sensory and central motor neurons"</p><p>http://www.neuraldevelopment.com/content/3/1/16</p><p>Neural Development 2008;3():16-16.</p><p>Published online 10 Jul 2008</p><p>PMCID:PMC2503983.</p><p></p

RP2 neurons at 25–31 hours AEL and visualised with in the context of FascicilinII positive axon bundles (magenta) demarcating the medial and lateral neuropile (maximal Z-projections of confocal image stacks)

Control. Misexpression of (activated ) leads to a lack of dendritic innervation of the medial neuropile (normally located anterior to the axon (arrowhead in (a)) and a concomitant expansion of dendrites in the lateral neuropile posterior to the axon (arrowhead in (b))). Dendritic extent anterior or posterior to the axon is indicated by brackets. Quantification of anterior, posterior and total (combined) maximal dendritic extent for controls (green, N = 10) and expression RP2 neurons (magenta, N = 8). The significance of pair-wise comparisons using Student's -test is indicated. Anterior is left and the ventral midline is down. Scale bar: 20 μm.<p><b>Copyright information:</b></p><p>Taken from "Identification of genes influencing dendrite morphogenesis in developing peripheral sensory and central motor neurons"</p><p>http://www.neuraldevelopment.com/content/3/1/16</p><p>Neural Development 2008;3():16-16.</p><p>Published online 10 Jul 2008</p><p>PMCID:PMC2503983.</p><p></p

Three-dimensional reconstructions from confocal image stacks of RP2 neurons at 25–31 hours AEL and visualised with generated with AMIRA software

Control. Misexpression of causes aberrant dendritic targeting to the posterior. Brackets in (a) indicate the dendritic tree. Dendrograms derived from the reconstructions with branch points highlighted in magenta and the cell body and axon offset from the dendritic tree by green. Quantification of the dendritic architectures for controls (green, N = 4) and expressing RP2 neurons (magenta, N = 4). The significance of pair-wise comparisons using Student's -test is indicated. Error bars indicate the standard error. Anterior is left and the ventral midline is down. Scale bar: 10 μm.<p><b>Copyright information:</b></p><p>Taken from "Identification of genes influencing dendrite morphogenesis in developing peripheral sensory and central motor neurons"</p><p>http://www.neuraldevelopment.com/content/3/1/16</p><p>Neural Development 2008;3():16-16.</p><p>Published online 10 Jul 2008</p><p>PMCID:PMC2503983.</p><p></p

Proportional Venn diagrams to describe the degree of overlap among genes that emerged from both screens

The total is shown at top left, and then broken down by the predicted site of gene product activity.<p><b>Copyright information:</b></p><p>Taken from "Identification of genes influencing dendrite morphogenesis in developing peripheral sensory and central motor neurons"</p><p>http://www.neuraldevelopment.com/content/3/1/16</p><p>Neural Development 2008;3():16-16.</p><p>Published online 10 Jul 2008</p><p>PMCID:PMC2503983.</p><p></p

Glial Cell Differentiation Is Not Required for Neuropile Subdivision

<div><p>ISN (red) and SN (green) motor neurons labelled in 15-h-old wild-type (A and C) and <i>gcm</i> mutant (B and D) embryos. The neuropile, visualised with anti-HRP, is shown in blue.</p> <p>(A and B) Motor neurons innervating ventral (VL3–VL4, RP3) internal (red) and external (green) muscles of a segment elaborate their dendrites in separate regions of the neuropile on either side of the segment border (asterisks). This is accentuated when neuromeres separate in <i>gcm</i> mutant embryos (B).</p> <p>(C and D) The DT1 motor neuron (red) is the only ISN motor neuron whose dendrites branch in the SN dendritic domain (green). This dendritic projection pattern is maintained in <i>gcm</i> mutant embryos (D). An SN VUM efferent neuron has also been labelled.</p> <p>Anterior is left and dorsal is up. Symbols and abbreviations: triangles, ventral midline; AC, anterior commissure; PC, posterior commissure; asterisks, dorsoventral channels (landmarks for the segment borders). Scale bar (not applicable to diagrams of CNS and muscle field): 10 μm.</p></div

The Myotopic Map Forms Independently of Target Muscles

<div><p>ISN motor neurons (red) with internal and SN motor neurons (green) with external muscle targets in a 15-h-old wild-type (A) and in an embryo, in which muscle formation had been suppressed by targeted expression of an activated form (intracellular domain) of Notch (<i>24B</i>-<i>GAL4</i>; <i>UAS</i>-<i>Notch</i>*) (B). In such muscleless embryos, the main nerve trunks (ISN and SN) still form and project into the periphery along distinctive paths. Thus, motor neurons whose axons project through these nerves can be retrogradely labelled. The neuropile, visualised with anti-HRP, is shown in blue. ISN and SN motor neuron dendritic domains show a normal separation despite absence of target muscles. Note that the ISN (red) and SN (green) dendritic arbors in (B) appear to be in closer proximity than those shown in (A). This is because in (B) the RP2 neuron (indicated) is labelled, which is the most posterior of the ISN motor neurons and therefore closest to the SN dendritic domain. See also <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0000041#pbio.0000041-g002" target="_blank">Figure 2</a>G, where RP2 and its dendrites are shown relative to the most posterior of the SN motor neuron (SBM) dendritic fields.</p> <p>Anterior is left and dorsal is up. Symbols and abbreviations: triangles, ventral midline; AC, anterior commissure; PC, posterior commissure; asterisks, dorsoventral channels (landmarks for the segment borders). Scale bar (not applicable to diagrams of CNS and muscle field): 10 μm.</p></div

Territories of Initial Dendritic Elaboration Are Not Defined by Mutual Exclusion

<div><p>(A) Dendrites of DO3 (as well as DO4–DO5 and DT1) (green) motor neurons always project posterior to the region in which the dendritic arbors of the aCC and U/CQ motor neurons (red) form.</p> <p>(B and C) <i>eve</i>-expressing motor neurons (aCC, U/CQs, and RP2) in stage 13 (approximately 10.5-h-old) wild-type embryos (B) and those in which the aCC, RP2, and U/CQ neurons had been selectively ablated (C). In (C), all medial <i>eve</i>-expressing neurons have been ablated by this stage, and only one, possibly the U/CQ neuron (likely the LL1 motor neuron), is still present in several segments. U in (B) marks all U/CQ neurons as well as the aCC motor and the pCC and fpCC interneurons contained in this group; EL marks the lateral <i>eve</i>-expressing interneurons.</p> <p>(D) Dendritic arborisations of the DO3–DO4 motor neurons do not elaborate anteriorly into the territory vacated by ablated aCC and U/CQ neurons.</p> <p>Anterior is left and dorsal is up. Symbols and abbreviations: triangles, ventral midline; AC, anterior commissure; PC, posterior commissure; asterisks, dorsoventral channels (landmarks for the segment borders). Scale bar in (A) and (D): 10 μm; in (B) and (C): 45 μm.</p></div

Parasegmental Organisation of the Motor System

<div><p>(A) Distribution of motor neuron dendritic arbors relative to the domains of <i>en</i> expression. Neurons expressing the <i>en</i> gene were visualised (blue) using <i>en-GAL4;UAS-CD8-GFP</i>. ISN motor neuron dendrites (red) elaborate in the En domain (blue) of the neuromere, whereas SN motor neuron dendrites (green) form in the anterior half of the next posterior segment (asterisks indicate the segment borders). Thus, the motor system appears to be parasegmental in nature. The diagrams to the right indicate which motor neurons were labelled.</p> <p>(B–H) ISN motor neurons (red) with dorsal internal and SN motor neurons (green) with lateral external muscle targets were retrogradely labelled in 15-h-old wild-type embryos (B) and those mutant for different segment polarity genes (C–H). (C) to (H) should be compared with the wild-type control in (B). As far as could be ascertained, similar sets of motor neurons were labelled in the wild-type (B) and mutants (C–H). The neuropile, visualised with anti-HRP, is shown in blue (except for [F]). In all mutant embryos, with the exception of <i>Df(gsb)</i> (H), ISN and SN motor neurons have separate nerve roots and dendritic fields, as in the wild-type. As (H) shows, in <i>Df(gsb)</i> mutant embryos, ISN and SN nerve roots are frequently fused, yet the respective dendritic fields (arrows) do not appear to intermingle.</p> <p>Anterior is left and dorsal is up. Symbols and abbreviations: triangles, ventral midline; AC, anterior commissure; PC, posterior commissure (RP2 cell bodies, the most posterior of the ISN motor neurons, are indicated in [C] and [E]); asterisks, dorsoventral channels (landmarks for the segment borders). Scale bar (not applicable to diagrams of CNS and muscle field): 10 μm.</p></div