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1
Dibal, Jibrin M., A. A. Ramalan, O. J. Mudiare, and H. E. Igbadun. "Scenario Studies on Effects of Soil Infiltration Rates, Land Slope, and Furrow Irrigation Characteristics on Furrow Irrigation-Induced Erosion." International Scholarly Research Notices 2014 (November 10, 2014): 1–6. http://dx.doi.org/10.1155/2014/942732.
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Furrow irrigation proceeds under several soil-water-furrow hydraulics interaction dynamics. The soil erosion consequences from such interactions in furrow irrigation in Samaru had remained uncertain. A furrow irrigation-induced erosion (FIIE) model was used to simulate the potential severity of soil erosion in irrigated furrows due to interactive effects of infiltration rates, land slope, and some furrow irrigation characteristics under different scenarios. The furrow irrigation characteristics considered were furrow lengths, widths, and stream sizes. The model itself was developed using the dimensional analysis approach. The scenarios studied were the interactive effects of furrow lengths, furrow widths, and slopes steepness; infiltration rates and furrow lengths; and stream sizes, furrow lengths, and slopes steepness on potential furrow irrigation-induced erosion, respectively. The severity of FIIE was found to relate somewhat linearly with slope and stream size, and inversely with furrow lengths and furrow width. The worst soil erosion (378.05 t/ha/yr) was found as a result of the interactive effects of 0.65 m furrow width, 50 m furrow length, and 0.25% slope steepness; and the least soil erosion (0.013 t/ha/yr) was induced by the combined effects of 0.5 l/s, 200 m furrow length, and 0.05% slope steepness. Evidently considering longer furrows in furrow irrigation designs would be a better alternative of averting excessive FIIE.
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Sherlekar, Aparna, and Richa Rikhy. "Syndapin promotes pseudocleavage furrow formation by actin organization in the syncytial Drosophila embryo." Molecular Biology of the Cell 27, no. 13 (July 2016): 2064–79. http://dx.doi.org/10.1091/mbc.e15-09-0656.
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Coordinated membrane and cytoskeletal remodeling activities are required for membrane extension in processes such as cytokinesis and syncytial nuclear division cycles in Drosophila. Pseudocleavage furrow membranes in the syncytial Drosophila blastoderm embryo show rapid extension and retraction regulated by actin-remodeling proteins. The F-BAR domain protein Syndapin (Synd) is involved in membrane tubulation, endocytosis, and, uniquely, in F-actin stability. Here we report a role for Synd in actin-regulated pseudocleavage furrow formation. Synd localized to these furrows, and its loss resulted in short, disorganized furrows. Synd presence was important for the recruitment of the septin Peanut and distribution of Diaphanous and F-actin at furrows. Synd and Peanut were both absent in furrow-initiation mutants of RhoGEF2 and Diaphanous and in furrow-progression mutants of Anillin. Synd overexpression in rhogef2 mutants reversed its furrow-extension phenotypes, Peanut and Diaphanous recruitment, and F-actin organization. We conclude that Synd plays an important role in pseudocleavage furrow extension, and this role is also likely to be crucial in cleavage furrow formation during cell division.
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Silverman-Gavrila, Rosalind V., Karen G. Hales, and Andrew Wilde. "Anillin-mediated Targeting of Peanut to Pseudocleavage Furrows Is Regulated by the GTPase Ran." Molecular Biology of the Cell 19, no. 9 (September 2008): 3735–44. http://dx.doi.org/10.1091/mbc.e08-01-0049.
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During early development in Drosophila, pseudocleavage furrows in the syncytial embryo prevent contact between neighboring spindles, thereby ensuring proper chromosome segregation. Here we demonstrate that the GTPase Ran regulates pseudocleavage furrow organization. Ran can exert control on pseudocleavage furrows independently of its role in regulating the microtubule cytoskeleton. Disruption of the Ran pathway prevented pseudocleavage furrow formation and restricted the depth and duration of furrow ingression of those pseudocleavage furrows that did form. We found that Ran was required for the localization of the septin Peanut to the pseudocleavage furrow, but not anillin or actin. Biochemical assays revealed that the direct binding of the nuclear transport receptors importin α and β to anillin prevented the binding of Peanut to anillin. Furthermore, RanGTP reversed the inhibitory action of importin α and β. On expression of a mutant form of anillin that lacked an importin α and β binding site, inhibition of Ran no longer restricted the depth and duration of furrow ingression in those pseudocleavage furrows that formed. These data suggest that anillin and Peanut are involved in pseudocleavage furrow ingression in syncytial embryos and that this process is regulated by Ran.
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Ludvigsen, Rolf. "Revision of Acheilus and Theodenisia (Late Cambrian, Trilobita)." Journal of Paleontology 60, no. 1 (January 1986): 61–67. http://dx.doi.org/10.1017/s002233600002151x.
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Acheilus Clark, 1924, is a kingstoniid trilobite, not a catillicephalid or an unrecognizable genus as previously thought. The catillicephalid Theodenisia Clark, 1948, is here restricted to those species in which the axial furrows terminate at the 4s furrow and which lack a preglabellar furrow. Peracheilus n. gen. is proposed as a replacement name for the catillicephalid Acheilus Raymond, 1924. It includes those species previously assigned to Theodenisia in which the axial furrows continue past the 4s furrow to join a narrow preglabellar furrow. Acheilus, Theodenisia, and Peracheilus occur in the Late Sunwaptan of North America; Theodenisia also occurs in the early Ibexian.
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Dibal, Jibrin M., H. E. Igbadun, A. A. Ramalan, and O. J. Mudiare. "Modelling Furrow Irrigation-Induced Erosion on a Sandy Loam Soil in Samaru, Northern Nigeria." International Scholarly Research Notices 2014 (November 11, 2014): 1–8. http://dx.doi.org/10.1155/2014/982136.
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Assessment of soil erosion and sediment yield in furrow irrigation is limited in Samaru-Zaria. Data was collected in 2009 and 2010 and was used to develop a dimensionless model for predicting furrow irrigation-induced erosion (FIIE) using the dimensional analyses approach considering stream size, furrow length, furrow width, soil infiltration rate, hydraulic shear stress, soil erodibility, and time flow of water in the furrows as the building components. One liter of water-sediment samples was collected from the furrows during irrigations from which sediment concentrations and soil erosion per furrow were calculated. Stream sizes Q (2.5, 1.5, and 0.5 l/s), furrow lengths X (90 and 45 m), and furrow widths W (0.75 and 0.9 m) constituted the experimental factors randomized in a split plot design with four replications. Water flow into and out of the furrows was measured using cutthroat flumes. The model produced reasonable predictions relative to field measurements with coefficient of determination R2 in the neighborhood of 0.8, model prediction efficiency NSE (0.7000), high index of agreement (0.9408), and low coefficient of variability (0.4121). The model is most sensitive to water stream size. The variables in the model are easily measurable; this makes it better and easily adoptable.
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Lentz, Rick D., Eduardo Bautista, Anita Koehn, and Robert Sojka. "Infiltration and Soil Water Distribution in Irrigation Furrows Treated with Polyacrylamide." Transactions of the ASABE 63, no. 5 (2020): 1451–64. http://dx.doi.org/10.13031/trans.13939.
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HighlightsControl furrows with 1× inflow rates were compared with 3× advance inflows treated with 10 mg L-1 polymer (WSPAM).WSPAM reduced sediment loads in furrow streams by 89%, despite its 3× greater advance inflows.WSPAM furrow advance times and infiltrated volumes were greater than predicted from increased inflows alone.WSPAM enabled reduced upper-section infiltration and increased lower-section infiltration relative to control furrows.Abstract. Few if any studies have measured the effects of water-soluble anionic polyacrylamide (WSPAM) on infiltration and soil water distribution in different segments of irrigation furrows. We conducted a four-year study on a silt loam soil with 1.5% slopes. Control furrows received no WSPAM and inflows were 15.1 L min-1, whereas WSPAM was applied using 10 mg L-1 a.i. to 45 L min-1 inflows during furrow advance. Despite its greater advance phase inflow rates, WSPAM application reduced sediment concentrations in furrow streams by an average of 89% relative to the control. A surface irrigation model, WinSRFR 5.1, was used to separate furrow inflow rate effects on infiltration from that of WSPAM. Relative to results predicted by simulation for the entire furrow, the polymer treatment: (1) increased advance time an average 1.4-fold, (2) increased advance-phase infiltrated volume 1.5-fold, and (3) increased infiltration volume at the common opportunity time 1.2-fold. Hence, these effects resulted from WSPAM and not from differences in treatment inflow rates. Treatment infiltration amounts varied markedly among irrigations and years, as did the intensity of WSPAM effects. These were attributed mainly to differences in infiltration opportunity time, but temporal differences in soil water content during furrow formation, irrigation water electrical conductivity, initial soil surface water content and water temperature, and the irrigation-long, furrow-stream mean sediment content also appear to have influenced infiltration rates. Although inconsistent, WSPAM increased net furrow infiltration in the lower section and reduced infiltration in the upper section relative to control furrows. This effect could not be explained by the greater inflow rate and shorter advance time of the WSPAM treatments and was attributed to spatially variable WSPAM effects on infiltration opportunity time and possibly irrigation water viscosity. The WSPAM management approach, while protecting against furrow erosion, may potentially provide a means of improving irrigation uniformity and reducing associated percolation water and nutrient losses. Keywords: Furrow advance, Irrigation, Irrigation uniformity, Polymers.
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Lewellyn, Lindsay, Julien Dumont, Arshad Desai, and Karen Oegema. "Analyzing the Effects of Delaying Aster Separation on Furrow Formation during Cytokinesis in the Caenorhabditis elegans Embryo." Molecular Biology of the Cell 21, no. 1 (January 2010): 50–62. http://dx.doi.org/10.1091/mbc.e09-01-0089.
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Signaling by the centrosomal asters and spindle midzone coordinately directs formation of the cytokinetic furrow. Here, we explore the contribution of the asters by analyzing the consequences of altering interaster distance during the first cytokinesis of the Caenorhabditis elegans embryo. Delaying aster separation, by using TPXL-1 depletion to shorten the metaphase spindle, leads to a corresponding delay in furrow formation, but results in a single furrow that ingresses at a normal rate. Preventing aster separation, by simultaneously inhibiting TPXL-1 and Gα signaling-based cortical forces pulling on the asters, delays furrow formation and leads to the formation of multiple furrows that ingress toward the midzone. Disrupting midzone-based signaling, by depleting conserved midzone complexes, results in a converse phenotype: neither the timing nor the number of furrows is affected, but the rate of furrow ingression is decreased threefold. Simultaneously delaying aster separation and disrupting midzone-based signaling leads to complete failure of furrow formation. Based on these results, we propose that signaling by the separated asters executes two critical functions: 1) it couples furrow formation to anaphase onset by concentrating contractile ring proteins on the equatorial cortex in a midzone-independent manner and 2) it subsequently refines spindle midzone-based signaling to restrict furrowing to a single site.
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Carroll, C., M. Halpin, K. Bell, and J. Mollison. "The effect of furrow length on rain and irrigation-induced erosion on a vertisol in Australia." Soil Research 33, no. 5 (1995): 833. http://dx.doi.org/10.1071/sr9950833.
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Runoff and sediment movement were measured from irrigated furrows of different lengths on a Vertisol in central Queensland. Two farm properties (Denaro's and Roberts') were used to compare a short furrow length (SFL) and a long furrow length (LFL). At Denaro's farm, furrows were 241 and 482 m long, and at Roberts' farm they were 151 and 298 m long, with gradients of 1.0% and 1.3% respectively. Runoff and soil loss were measured from six furrows. At Denaro's farm, soil movement off the farm was measured at a taildrain outlet. Sediment concentration from both rainfall and irrigation declined when cultivation had ceased, soil in the furrows had consolidated and when the cotton canopy provided surface cover. Total soil loss from rainfall and irrigation was approximately 4-5 t ha-1. Rainstorms caused most of the seasonal soil loss, typically 3-4 t ha-1. The critical soil erosion period was between pre-plant irrigation and canopy closure. Soil surface cover, peak runoff rate and furrow length explained 97% of variance in soil loss caused by rainfall. Furrow length was not significant in the soil loss model for irrigation (r2 0.59).
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Albertson, Roger, Jian Cao, Tao-shih Hsieh, and William Sullivan. "Vesicles and actin are targeted to the cleavage furrow via furrow microtubules and the central spindle." Journal of Cell Biology 181, no. 5 (May 26, 2008): 777–90. http://dx.doi.org/10.1083/jcb.200803096.
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During cytokinesis, cleavage furrow invagination requires an actomyosin-based contractile ring and addition of new membrane. Little is known about how this actin and membrane traffic to the cleavage furrow. We address this through live analysis of fluorescently tagged vesicles in postcellularized Drosophila melanogaster embryos. We find that during cytokinesis, F-actin and membrane are targeted as a unit to invaginating furrows through formation of F-actin–associated vesicles. F-actin puncta strongly colocalize with endosomal, but not Golgi-derived, vesicles. These vesicles are recruited to the cleavage furrow along the central spindle and a distinct population of microtubules (MTs) in contact with the leading furrow edge (furrow MTs). We find that Rho-specific guanine nucleotide exchange factor mutants, pebble (pbl), severely disrupt this F-actin–associated vesicle transport. These transport defects are a consequence of the pbl mutants' inability to properly form furrow MTs and the central spindle. Transport of F-actin–associated vesicles on furrow MTs and the central spindle is thus an important mechanism by which actin and membrane are delivered to the cleavage furrow.
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Onishi, Masayuki, James G. Umen, Frederick R. Cross, and John R. Pringle. "Cleavage-furrow formation without F-actin inChlamydomonas." Proceedings of the National Academy of Sciences 117, no. 31 (July 20, 2020): 18511–20. http://dx.doi.org/10.1073/pnas.1920337117.
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It is widely believed that cleavage-furrow formation during cytokinesis is driven by the contraction of a ring containing F-actin and type-II myosin. However, even in cells that have such rings, they are not always essential for furrow formation. Moreover, many taxonomically diverse eukaryotic cells divide by furrowing but have no type-II myosin, making it unlikely that an actomyosin ring drives furrowing. To explore this issue further, we have used one such organism, the green algaChlamydomonas reinhardtii. We found that although F-actin is associated with the furrow region, none of the three myosins (of types VIII and XI) is localized there. Moreover, when F-actin was eliminated through a combination of a mutation and a drug, furrows still formed and the cells divided, although somewhat less efficiently than normal. Unexpectedly, division of the largeChlamydomonaschloroplast was delayed in the cells lacking F-actin; as this organelle lies directly in the path of the cleavage furrow, this delay may explain, at least in part, the delay in cytokinesis itself. Earlier studies had shown an association of microtubules with the cleavage furrow, and we used a fluorescently tagged EB1 protein to show that microtubules are still associated with the furrows in the absence of F-actin, consistent with the possibility that the microtubules are important for furrow formation. We suggest that the actomyosin ring evolved as one way to improve the efficiency of a core process for furrow formation that was already present in ancestral eukaryotes.
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Wagner, Elizabeth, and Michael Glotzer. "Local RhoA activation induces cytokinetic furrows independent of spindle position and cell cycle stage." Journal of Cell Biology 213, no. 6 (June 13, 2016): 641–49. http://dx.doi.org/10.1083/jcb.201603025.
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The GTPase RhoA promotes contractile ring assembly and furrow ingression during cytokinesis. Although many factors that regulate RhoA during cytokinesis have been characterized, the spatiotemporal regulatory logic remains undefined. We have developed an optogenetic probe to gain tight spatial and temporal control of RhoA activity in mammalian cells and demonstrate that cytokinetic furrowing is primarily regulated at the level of RhoA activation. Light-mediated recruitment of a RhoGEF domain to the plasma membrane leads to rapid induction of RhoA activity, leading to assembly of cytokinetic furrows that partially ingress. Furthermore, furrow formation in response to RhoA activation is not temporally or spatially restricted. RhoA activation is sufficient to generate furrows at both the cell equator and cell poles, in both metaphase and anaphase. Remarkably, furrow formation can be initiated in rounded interphase cells, but not adherent cells. These results indicate that RhoA activation is sufficient to induce assembly of functional contractile rings and that cell rounding facilitates furrow formation.
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Shannon, Katie B., Julie C. Canman, C. Ben Moree, Jennifer S. Tirnauer, and E. D. Salmon. "Taxol-stabilized Microtubules Can Position the Cytokinetic Furrow in Mammalian Cells." Molecular Biology of the Cell 16, no. 9 (September 2005): 4423–36. http://dx.doi.org/10.1091/mbc.e04-11-0974.
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How microtubules act to position the plane of cell division during cytokinesis is a topic of much debate. Recently, we showed that a subpopulation of stable microtubules extends past chromosomes and interacts with the cell cortex at the site of furrowing, suggesting that these stabilized microtubules may stimulate contractility. To test the hypothesis that stable microtubules can position furrows, we used taxol to rapidly suppress microtubule dynamics during various stages of mitosis in PtK1 cells. Cells with stabilized prometaphase or metaphase microtubule arrays were able to initiate furrowing when induced into anaphase by inhibition of the spindle checkpoint. In these cells, few microtubules contacted the cortex. Furrows formed later than usual, were often aberrant, and did not progress to completion. Images showed that furrowing correlated with the presence of one or a few stable spindle microtubule plus ends at the cortex. Actin, myosin II, and anillin were all concentrated in these furrows, demonstrating that components of the contractile ring can be localized by stable microtubules. Inner centromere protein (INCENP) was not found in these ingressions, confirming that INCENP is dispensable for furrow positioning. Taxol-stabilization of the numerous microtubule-cortex interactions after anaphase onset delayed furrow initiation but did not perturb furrow positioning. We conclude that taxol-stabilized microtubules can act to position the furrow and that loss of microtubule dynamics delays the timing of furrow onset and prevents completion. We discuss our findings relative to models for cleavage stimulation.
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Brennan, Eric B., and Richard F. Smith. "Mustard Cover Crop Growth and Weed Suppression in Organic, Strawberry Furrows in California." HortScience 53, no. 4 (April 2018): 432–40. http://dx.doi.org/10.21273/hortsci12576-17.
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Strawberry (Fragaria ×ananassa Duch.) production in California uses plastic mulch–covered beds that provide many benefits such as moisture conservation and weed control. Unfortunately, the mulch can also cause environmental problems by increasing runoff and soil erosion and reducing groundwater recharge. Planting cover crops in bare furrows between the plastic cover beds can help minimize these problems. Furrow cover cropping was evaluated during two growing seasons in organic strawberries in Salinas, CA, using a mustard (Sinapis alba L.) cover crop planted at two seeding rates (1× and 3×). Mustard was planted in November or December after strawberry transplanting and it resulted in average densities per meter of furrow of 54 and 162 mustard plants for the 1× and 3× rates, respectively. The mustard was mowed in February before it shaded the strawberry plants. Increasing the seeding rate increased mustard shoot biomass and height, and reduced the concentration of P in the mustard shoots. Compared with furrows with no cover crop, cover-cropped furrows reduced weed biomass by 29% and 40% in the 1× and 3× seeding rates, respectively, although weeds still accounted for at least 28% of the furrow biomass in the cover-cropped furrows. These results show that growing mustard cover crops in furrows without irrigating the furrows worked well even during years with relatively minimal precipitation. We conclude that 1) mustard densities of ≈150 plants/m furrow will likely provide the most benefits due to greater biomass production, N scavenging, and weed suppression; 2) mowing was an effective way to kill the mustard; and 3) high seeding rates of mustard alone are insufficient to provide adequate weed suppression in strawberry furrows.
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Uteniyazov, Pulat A. "Theoretical Study of Working Tool Placement in the Combined Unit." Agricultural Machinery and Technologies 12, no. 6 (December 24, 2018): 4–8. http://dx.doi.org/10.22314/2073-7599-2018-12-6-4-8.
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Abstract. The author proves that organic fertilizers, unlike the mineral ones, are capable of increasing yields over several years; they do not harm the environment and do not pollute the melon crop fields with nitrates. It has been clarified that their introduction is one of the most effective methods of humus conservation and soil fertility enhancement, which means obtaining fuller yields of high-quality melons and gourds. The NIIMESH researchers have developed a combined unit for local application of organic fertilizers for melons and gourds. (Research purpose) Conducting theoretical studies on the substantiation of the configuration of the working tools of a combined unit for local application of organic fertilizers. (Materials and methods) The author has conducted theoretical studies using methods of analytical geometry and theoretical mechanics. (Results and discussion) Analytical dependences have been obtained to determine transverse distances between furrow shapers used for applying organic fertilizers and making an irrigation groove, as well as longitudinal distances between the tractor's rear wheels and the furrow shapers applying organic fertilizers, between the furrow shapers and the fertilizer spreader, and between the fertilizer spreader and the furrow shaper making an irrigation furrow. (Conclusions) It has been determined that transverse distance between the working tools that make furrows for applying organic fertilizers should range between 0.9 and 1.3 metre, transverse distance between the working tools making an irrigation furrow and a furrow for the application of organic fertilizers is 0.45-0.65 metre. The optimal values of longitudinal distances have been found as well: between the tractor's rear wheels and the working tools making furrows for applying fertilizers – no less than 0.21 metre, between the tip of working tools and the fertilizer spreader – no less than 1.5 metre, and between the fertilizer spreader center and the tip of working tools making an irrigation furrow – at least 0.74 metre.
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Lespérance, Pierre J. "Vincular furrows in some Early Silurian and Devonian Phacopidae (Trilobita), predominantly from North America." Journal of Paleontology 65, no. 2 (March 1991): 276–94. http://dx.doi.org/10.1017/s0022336000020515.
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The vincular furrow morphology of 19 species of Phacopidae is critically examined. The anterior part of the vincular furrow is much less variable than the posterior part of the vincular furrow, but it can be absent, shallow, deep, or have a slightly ventrally elongated boss. The posterior part of the vincular furrow can have pleurovincular pits (for reception of the thoracic pleural tip processes) or indentations for these processes, plus bounding walls that are variably indented laterally and very variable in vertical elongation. The functional morphology of the various elements of the vincular furrow is best explained by a paradigm of resistance to lateral shearing.All elements of the vincular furrow in Devonian taxa had already appeared in the Early Silurian, but Early Silurian taxa are richer in diversity of elements. Some Devonian subspecies, essentially based on dorsal morphologies, show distinctly different vincular furrows. Cluster analysis of the data gathered on the vincular furrow complexes regroups the distinctly different Devonian subspecies and some Silurian subgenera. Other vincular furrows within the Phacopidae suggest that Reedops is near the Phacops logani complex and that the Phacopidellinae is a valid subfamily, but formal emendations within the family are not suggested because of incomplete data, notably on our knowledge of the distribution of vincular furrows. The use of the widely conceived genus Phacops Emmrich, 1839, over more recently described taxa such as Paciphacops Maximova, 1972, is presently favored, as this reflects more clearly current understanding of the systematics within the family Phacopidae.Primary types of the North American taxa Phacops cristata, P. cristata gaspensis, and Acernaspis (Acernaspis) orestes are critically reviewed; significant changes of previous interpretations are suggested. Phacops cristata vitrea n. subsp. is erected. Thoracic pleural tip processes and anterolateral ventral pygidial processes are described in detail within Phacops rana rana and Acernaspis (Acernaspis) orestes. A pathological specimen of Phacops rana rana, with an injured eye, demonstrates that the individual did not revert to a primitive type of lens packing.
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Eckley, D. Mark, Alexandra M. Ainsztein, Alastair M. Mackay, Ilya G. Goldberg, and William C. Earnshaw. "Chromosomal Proteins and Cytokinesis: Patterns of Cleavage Furrow Formation and Inner Centromere Protein Positioning in Mitotic Heterokaryons and Mid-anaphase Cells." Journal of Cell Biology 136, no. 6 (March 24, 1997): 1169–83. http://dx.doi.org/10.1083/jcb.136.6.1169.
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After the separation of sister chromatids in anaphase, it is essential that the cell position a cleavage furrow so that it partitions the chromatids into two daughter cells of roughly equal size. The mechanism by which cells position this cleavage furrow remains unknown, although the best current model is that furrows always assemble midway between asters. We used micromanipulation of human cultured cells to produce mitotic heterokaryons with two spindles fused in a V conformation. The majority (15/19) of these cells cleaved along a single plane that transected the two arms of the V at the position where the metaphase plate had been, a result at odds with current views of furrow positioning. However, four cells did form an additional ectopic furrow between the spindle poles at the open end of the V, consistent with the established view. To begin to address the mechanism of furrow assembly, we have begun a detailed study of the properties of the chromosome passenger inner centromere protein (INCENP) in anaphase and telophase cells. We found that INCENP is a very early component of the cleavage furrow, accumulating at the equatorial cortex before any noticeable cortical shape change and before any local accumulation of myosin heavy chain. In mitotic heterokaryons, INCENP was detected in association with spindle midzone microtubules beneath sites of furrowing and was not detected when furrows were absent. A functional role for INCENP in cytokinesis was suggested in experiments where a nearly full-length INCENP was tethered to the centromere. Many cells expressing the chimeric INCENP failed to complete cytokinesis and entered the next cell cycle with daughter cells connected by a large intercellular bridge with a prominent midbody. Together, these results suggest that INCENP has a role in either the assembly or function of the cleavage furrow.
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Kassaye, Kassu Tadesse, Wubengeda Admasu Yilma, Mehiret Hone Fisha, and Dawit Habte Haile. "Yield and Water Use Efficiency of Potato under Alternate Furrows and Deficit Irrigation." International Journal of Agronomy 2020 (November 24, 2020): 1–11. http://dx.doi.org/10.1155/2020/8869098.
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The benefits of water-saving techniques such as alternate furrow and deficit irrigations need to be explored to ensure food security for the ever-increasing population within the context of declining availability of irrigation water. In this regard, field experiments were conducted for 2 consecutive dry seasons in the semiarid region of southwestern Ethiopia and investigated the influence of alternate furrow irrigation method with different irrigation levels on the yield, yield components, water use efficiency, and profitability of potato production. The experiment comprised of 3 irrigation methods: (i) conventional furrow irrigation (CFI), (ii) alternate furrow irrigation (AFI), and (iii) fixed furrow irrigation (FFI) combined factorially with 3 irrigation regimes: (i) 100%, (ii) 75%, and (iii) 50% of the potato water requirement (ETC). The experiment was laid out in randomized complete block design replicated thrice. Results revealed that seasonal irrigation water applied in alternate furrows was nearly half (170 mm) of the amount supplied in every furrow (331 mm). Despite the half reduction in the total amount of water, tuber (35.68 t ha−1) and total biomass (44.37 t ha−1) yields of potato in AFI did not significantly differ from CFI (34.84 and 45.35 t ha−1, respectively). Thus, AFI improved WUE by 49% compared to CFI. Irrigating potato using 75% of ETC produced tuber yield of 35.01 t ha−1, which was equivalent with 100% of ETC (35.18 t ha−1). Irrigating alternate furrows using 25% less ETC provided the highest net return of US$74.72 for every unit investment on labor for irrigating potato. In conclusion, irrigating alternate furrows using up to 25% less ETC saved water, provided comparable yield, and enhanced WUE and economic benefit. Therefore, farmers and experts are recommended to make change to AFI with 25% deficit irrigation in the study area and other regions with limited water for potato production to improve economic, environmental, and social performance of their irrigated systems.
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Fluck, R. A., A. L. Miller, and L. F. Jaffe. "Slow calcium waves accompany cytokinesis in medaka fish eggs." Journal of Cell Biology 115, no. 5 (December 1, 1991): 1259–65. http://dx.doi.org/10.1083/jcb.115.5.1259.
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Animal cells are cleaved by the formation and contraction of an extremely thin actomyosin band. In most cases this contractile band seems to form synchronously around the whole equator of the cleaving cell; however in giant cells it first forms near the mitotic apparatus and then slowly grows outwards over the cell. We studied the relationship of calcium to such contractile band growth using aequorin injected medaka fish eggs: we see two successive waves of faint luminescence moving along each of the first three cleavage furrows at approximately 0.5 micron/s. The first, narrower waves accompany furrow extension, while the second, broader ones, accompany the subsequent apposition or slow zipping together of the separating cells. If the first waves travel within the assembling contractile band, they would indicate local increases of free calcium to concentrations of about five to eight micromolar. This is the first report to visualize high free calcium within cleavage furrows. Moreover, this is also the first report to visualize slow (0.3-1.0 micron/s) as opposed to fast (10-100 microns/s) calcium waves. We suggest that these first waves are needed for furrow growth; that in part they further furrow growth by speeding actomyosin filament shortening, while such shortening in turn acts to mechanically release calcium and thus propagates these waves as well as furrow growth. We also suggest that the second waves act to induce the exocytosis which provides new furrow membrane.
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YONEMURA, SHIGENOBU, ISSEI MABUCHI, and SHOICHIRO TSUKITA. "Mass Isolation of Cleavage Furrows from Dividing Sea Urchin Eggs." Journal of Cell Science 100, no. 1 (September 1, 1991): 73–84. http://dx.doi.org/10.1242/jcs.100.1.73.
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To develop a mass isolation procedure for the cleavage furrow from synchronized sea urchin eggs, we compared the stability of the cleavage furrow with that of the rest of the cortex (polar-region cortex) and the inner cytoplasm under various conditions using the rhodamine-phalloidin staining method. As a result, to remove the polar-region cortex and leave the cleavage furrow intact, it became clear that the type and concentration of detergent, the pH and Ca concentration of the isolation solution and the temperature were of critical importance, and that 0.04-0.1 % Nonidet P-40, pH 7.0-7.5, low calcium ion concentration and room temperature were optimal conditions. To solubilize the inner cytoplasm to release intact cleavage furrows, two factors, osmotic pressure and sea urchin species, were found to be important: 0.16 M glucose (or sucrose) was optimal, and we found Clypeaster japonicus to be the most appropriate. A shearing force, by gentle pipetting, was also required for furrow isolation. Taking these results into consideration, we have succeeded in developing a mass isolation procedure for cleavage furrow from C. japonicus. A total of 20–50 μg of protein of isolated cleavage furrow was recovered from 1 ml of packed dividing eggs. The structural integrity of the isolated cleavage furrow was well maintained and it was characterized by remnants of plasma membranes, actin filament meshwork including a contractile ring, and cytoplasmic vacuoles. Although the isolated furrow contained myosin II molecules, it showed no capability of in vitro reactivation.
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Liu, Jiangshu, Donghoon M. Lee, Cao Guo Yu, Stephane Angers, and Tony J. C. Harris. "Stepping stone: a cytohesin adaptor for membrane cytoskeleton restraint in the syncytial Drosophila embryo." Molecular Biology of the Cell 26, no. 4 (February 15, 2015): 711–25. http://dx.doi.org/10.1091/mbc.e14-11-1554.
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Cytohesin Arf-GEFs are conserved plasma membrane regulators. The sole Drosophila cytohesin, Steppke, restrains Rho1-dependent membrane cytoskeleton activity at the base of plasma membrane furrows of the syncytial embryo. By mass spectrometry, we identified a single major Steppke-interacting protein from syncytial embryos, which we named Stepping stone (Sstn). By sequence, Sstn seems to be a divergent homologue of the mammalian cytohesin adaptor FRMD4A. Our experiments supported this relationship. Specifically, heterophilic coiled-coil interactions linked Sstn and Steppke in vivo and in vitro, whereas a separate C-terminal region was required for Sstn localization to furrows. Sstn mutant and RNAi embryos displayed abnormal, Rho1-dependent membrane cytoskeleton expansion from the base of pseudocleavage and cellularization furrows, closely mimicking Steppke loss-of-function embryos. Elevating Sstn furrow levels had no effect on the steppke phenotype, but elevating Steppke furrow levels reversed the sstn phenotype, suggesting that Steppke acts downstream of Sstn and that additional mechanisms can recruit Steppke to furrows. Finally, the coiled-coil domain of Steppke was required for Sstn binding and in addition homodimerization, and its removal disrupted Steppke furrow localization and activity in vivo. Overall we propose that Sstn acts as a cytohesin adaptor that promotes Steppke activity for localized membrane cytoskeleton restraint in the syncytial Drosophila embryo.
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Chanut, F., and U. Heberlein. "Role of the morphogenetic furrow in establishing polarity in the Drosophila eye." Development 121, no. 12 (December 1, 1995): 4085–94. http://dx.doi.org/10.1242/dev.121.12.4085.
Full textAbstract:
The Drosophila retina is a crystalline array of 800 ommatidia whose organization and assembly suggest polarization of the retinal epithelium along anteroposterior and dorsoventral axes. The retina develops by a stepwise process following the posterior-to-anterior progression of the morphogenetic furrow across the eye disc. Ectopic expression of hedgehog or local removal of patched function generates ectopic furrows that can progress in any direction across the disc leaving in their wake differentiating fields of ectopic ommatidia. We have studied the effect of these ectopic furrows on the polarity of ommatidial assembly and rotation. We find that the anteroposterior asymmetry of ommatidial assembly parallels the progression of ectopic furrows, regardless of their direction. In addition, ommatidia developing behind ectopic furrows rotate coordinately, forming equators in various regions of the disc. Interestingly, the expression of a marker normally restricted to the equator is induced in ectopic ommatidial fields. Ectopic equators are stable as they persist to adulthood, where they can coexist with the normal equator. Our results suggest that ectopic furrows can impart polarity to the disc epithelium, regarding the direction of both assembly and rotation of ommatidia. We propose that these processes are polarized as a consequence of furrow propagation, while more global determinants of dorsoventral and anteroposterior polarity may act less directly by determining the site of furrow initiation.
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Ma, C., and K. Moses. "Wingless and patched are negative regulators of the morphogenetic furrow and can affect tissue polarity in the developing Drosophila compound eye." Development 121, no. 8 (August 1, 1995): 2279–89. http://dx.doi.org/10.1242/dev.121.8.2279.
Full textAbstract:
In the developing Drosophila compound eye, a wave of pattern formation and cell-type determination sweeps across the presumptive eye epithelium. This ‘morphogenetic furrow’ coordinates the epithelial cells' division cycle, shape and gene expression to produce evenly spaced neural cell clusters that will eventually form the adult ommatidia. As these clusters develop, they rotate inwards to face the eye's equator and establish tissue polarity. We have found that wingless is strongly expressed in the dorsal margin of the presumptive eye field, ahead of the morphogenetic furrow. We have shown that inactivation of Wingless results in the induction of an ectopic furrow that proceeds ventrally from the dorsal margin. This ectopic furrow is normal in most respects, however the clusters formed by it fail to rotate, and we propose a two-vector model to account for normal rotation and tissue polarity in the retina. A second consequence of this inactivation of Wingless is that the dorsal head is largely deleted. We have also found that patched loss-of-function mosaic clones induce circular ectopic morphogenetic furrows (consistent with the observations of other workers with the hedgehog, and PKA genes). We use such patched induced furrows to test the two-vector model for cluster rotation and tissue polarity.
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Royou, Anne, Christine Field, John C. Sisson, William Sullivan, and Roger Karess. "Reassessing the Role and Dynamics of Nonmuscle Myosin II during Furrow Formation in Early Drosophila Embryos." Molecular Biology of the Cell 15, no. 2 (February 2004): 838–50. http://dx.doi.org/10.1091/mbc.e03-06-0440.
Full textAbstract:
The early Drosophila embryo undergoes two distinct membrane invagination events believed to be mechanistically related to cytokinesis: metaphase furrow formation and cellularization. Both involve actin cytoskeleton rearrangements, and both have myosin II at or near the forming furrow. Actin and myosin are thought to provide the force driving membrane invagination; however, membrane addition is also important. We have examined the role of myosin during these events in living embryos, with a fully functional myosin regulatory light-chain-GFP chimera. We find that furrow invagination during metaphase and cellularization occurs even when myosin activity has been experimentally perturbed. In contrast, the basal closure of the cellularization furrows and the first cytokinesis after cellularization are highly dependent on myosin. Strikingly, when ingression of the cellularization furrow is experimentally inhibited by colchicine treatment, basal closure still occurs at the appropriate time, suggesting that it is regulated independently of earlier cellularization events. We have also identified a previously unrecognized reservoir of particulate myosin that is recruited basally into the invaginating furrow in a microfilament-independent and microtubule-dependent manner. We suggest that cellularization can be divided into two distinct processes: furrow ingression, driven by microtubule mediated vesicle delivery, and basal closure, which is mediated by actin/myosin based constriction.
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von Dassow, George, Koen J. C. Verbrugghe, Ann L. Miller, Jenny R. Sider, and William M. Bement. "Action at a distance during cytokinesis." Journal of Cell Biology 187, no. 6 (December 14, 2009): 831–45. http://dx.doi.org/10.1083/jcb.200907090.
Full textAbstract:
Animal cells decide where to build the cytokinetic apparatus by sensing the position of the mitotic spindle. Reflecting a long-standing presumption that a furrow-inducing stimulus travels from spindle to cortex via microtubules, debate continues about which microtubules, and in what geometry, are essential for accurate cytokinesis. We used live imaging in urchin and frog embryos to evaluate the relationship between microtubule organization and cytokinetic furrow position. In normal cells, the cytokinetic apparatus forms in a region of lower cortical microtubule density. Remarkably, cells depleted of astral microtubules conduct accurate, complete cytokinesis. Conversely, in anucleate cells, asters alone can support furrow induction without a spindle, but only when sufficiently separated. Ablation of a single centrosome displaces furrows away from the remaining centrosome; ablation of both centrosomes causes broad, inefficient furrowing. We conclude that the asters confer accuracy and precision to a primary furrow-inducing signal that can reach the cell surface from the spindle without transport on microtubules.
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Muto, A., S. Kume, T. Inoue, H. Okano, and K. Mikoshiba. "Calcium waves along the cleavage furrows in cleavage-stage Xenopus embryos and its inhibition by heparin." Journal of Cell Biology 135, no. 1 (October 1, 1996): 181–90. http://dx.doi.org/10.1083/jcb.135.1.181.
Full textAbstract:
Calcium signaling is known to be associated with cytokinesis; however, the detailed spatio-temporal pattern of calcium dynamics has remained unclear. We have studied changes of intracellular free calcium in cleavage-stage Xenopus embryos using fluorescent calcium indicator dyes, mainly Calcium Green-1. Cleavage formation was followed by calcium transients that localized to cleavage furrows and propagated along the furrows as calcium waves. The calcium transients at the cleavage furrows were observed at each cleavage furrow at least until blastula stage. The velocity of the calcium waves at the first cleavage furrow was approximately 3 microns/s, which was much slower than that associated with fertilization/egg activation. These calcium waves traveled only along the cleavage furrows and not in the direction orthogonal to the furrows. These observations imply that there exists an intracellular calcium-releasing activity specifically associated with cleavage furrows. The calcium waves occurred in the absence of extracellular calcium and were inhibited in embryos injected with heparin an inositol 1,4,5-trisphosphate (InsP3) receptor antagonist. These results suggest that InsP3 receptor-mediated calcium mobilization plays an essential role in calcium wave formation at the cleavage furrows.
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Oegema, Karen, Matthew S. Savoian, Timothy J. Mitchison, and Christine M. Field. "Functional Analysis of a Human Homologue of the Drosophila Actin Binding Protein Anillin Suggests a Role in Cytokinesis." Journal of Cell Biology 150, no. 3 (August 7, 2000): 539–52. http://dx.doi.org/10.1083/jcb.150.3.539.
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We have characterized a human homologue of anillin, a Drosophila actin binding protein. Like Drosophila anillin, the human protein localizes to the nucleus during interphase, the cortex following nuclear envelope breakdown, and the cleavage furrow during cytokinesis. Anillin also localizes to ectopic cleavage furrows generated between two spindles in fused PtK1 cells. Microinjection of antianillin antibodies slows cleavage, leading to furrow regression and the generation of multinucleate cells. GFP fusions that contain the COOH-terminal 197 amino acids of anillin, which includes a pleckstrin homology (PH) domain, form ectopic cortical foci during interphase. The septin Hcdc10 localizes to these ectopic foci, whereas myosin II and actin do not, suggesting that anillin interacts with the septins at the cortex. Robust cleavage furrow localization requires both this COOH-terminal domain and additional NH2-terminal sequences corresponding to an actin binding domain defined by in vitro cosedimentation assays. Endogenous anillin and Hcdc10 colocalize to punctate foci associated with actin cables throughout mitosis and the accumulation of both proteins at the cell equator requires filamentous actin. These results indicate that anillin is a conserved cleavage furrow component important for cytokinesis. Interactions with at least two other furrow proteins, actin and the septins, likely contribute to anillin function.
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Edy, Edy, Didik Indradewa2, and Dja’far Shiddieq. "TANGGAP TANAMAN JAGUNG TERHADAP PEMUPUKAN KALIUM DAN PEMBUATAN PARIT PADA LAHAN KERING." AGROTEK: Jurnal Ilmiah Ilmu Pertanian 4, no. 1 (July 1, 2020): 88–98. http://dx.doi.org/10.33096/agrotek.v4i1.96.
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Water management in rainfed dry land is very important to consider. Limited water on dry land can be pursued with rain harvesting technology among others, by making a furrow filled with organic matter in situ. In anticipation of drought stress during the growth period of maize given the optimum potassium fertilizer to make it more survive when low rainfall that the productivity results remain stable. This study aims to determine response of masize to potassium fertilization and treatment of furrow on improvement of maize yield on dry land. The research was conducted in the Village of Wareng, sub District of Wonosari, District of Gunungkidul Province of D.I. Yogyakarta, which take place from November 2010 - February 2011. The design used is the design of Splite plots, with the main plot is designed in a Latin Square. The main plot is the trench model consists of three standard Furrows: Without the furrow (Control, P0), Furrow (P1), Furrow+organic matter (P2). Potassium fertilization subplot is comprised of 3 levels: without potassium fertilization (control, K0), 37.5 kg KCl.ha-1 (K1) and 75 kg KCl.ha-1 (K2). To obtain 9 combined treatment was repeated 3 times. Corn varieties tested were Bima-2 Bantimurung. The results showed that the combination of furrow+ organic matter and 75 kg KCl.ha-1 can increase soil moisture between 3-17%, plant growth rate 35-85%, water-use efficiency 33% and yield of corn per hectare 30%.
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Francetto, Tiago R., Airton Dos S. Alonço, Catize Brandelero, Otávio D. da C. Machado, André A. Veit, and Dauto P. Carpes. "Disturbance of Ultisol soil based on interactions between furrow openers and coulters for the no-tillage system." Spanish Journal of Agricultural Research 14, no. 3 (August 31, 2016): e0208. http://dx.doi.org/10.5424/sjar/2016143-9148.
Full textAbstract:
The present study evaluated the effect of different associations between coulters and fertilizer furrow openers on soil disturbance, furrow depth and width, according to forward speed. The study was conducted on a farm in Santa Maria (Brazil/RS), in soil classified as sandy loam Ultisol. The experiment consisted of 24 combinations of treatments with three replications in a 2×3×4 factorial experiment. The combinations were formed by the interaction of the factors including: two types of furrow openers (hoe and double-disc), three types of coulters (no-coulter, smooth and offset fluted) and four levels of forward speed (1.11, 1.67, 2.22 and 2.78 m/s). Soil elevation and soil disturbance area profiles were obtained with the use of a micro profilometer, and disturbance values were calculated with the aid of computer software program Auto Cad. The disturbance area was not affected by speed; it was greater when using the hoe opener, and in association with the offset fluted coulter. Speed was inversely proportional to the depth of the furrows made by the hoe opener. Furthermore, the hoe caused the greatest furrow width (0.26 m) in comparison with the double-disc (0.24 m). The use of different coulters associated with furrow openers increased this variable (0.23 m for the no-coulter condition, 0.25 m with smooth and 0.26 m with offset fluted). The use of coulters combined with furrow openers reduces soil swelling, in approximately 8% for the smooth and 20% for the offset fluted.
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Rothwell, W. F., C. X. Zhang, C. Zelano, T. S. Hsieh, and W. Sullivan. "The Drosophila centrosomal protein Nuf is required for recruiting Dah, a membrane associated protein, to furrows in the early embryo." Journal of Cell Science 112, no. 17 (September 1, 1999): 2885–93. http://dx.doi.org/10.1242/jcs.112.17.2885.
Full textAbstract:
During mitosis of the Drosophila cortical syncytial divisions, actin-based membrane furrows separate adjacent spindles. Our genetic analysis indicates that the centrosomal protein Nuf is specifically required for recruitment of components to the furrows and the membrane-associated protein Dah is primarily required for the inward invagination of the furrow membrane. Recruitment of actin, anillin and peanut to the furrows occurs normally in dah-derived embryos. However, subsequent invagination of the furrows fails in dah-derived embryos and the septins become dispersed throughout the cytoplasm. This indicates that stable septin localization requires Dah-mediated furrow invagination. Close examination of actin and Dah localization in wild-type embryos reveals that they associate in adjacent particles during interphase and co-localize in the invaginating furrows during prophase and metaphase. We show that the Nuf centrosomal protein is required for recruiting the membrane-associated protein Dah to the furrows. In nuf-mutant embryos, much of the Dah does not reach the furrows and remains in a punctate distribution. This suggests that Dah is recruited to the furrows in vesicles and that the recruiting step is disrupted in nuf mutants. These studies lead to a model in which the centrosomes play an important role in the transport of membrane-associated proteins and other components to the developing furrows.
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Mailapalli, Damodhara R., Narendra S. Raghuwanshi, and Rajendra Singh. "Sediment Transport Model for a Surface Irrigation System." Applied and Environmental Soil Science 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/957956.
Full textAbstract:
Controlling irrigation-induced soil erosion is one of the important issues of irrigation management and surface water impairment. Irrigation models are useful in managing the irrigation and the associated ill effects on agricultural environment. In this paper, a physically based surface irrigation model was developed to predict sediment transport in irrigated furrows by integrating an irrigation hydraulic model with a quasi-steady state sediment transport model to predict sediment load in furrow irrigation. The irrigation hydraulic model simulates flow in a furrow irrigation system using the analytically solved zero-inertial overland flow equations and 1D-Green-Ampt, 2D-Fok, and Kostiakov-Lewis infiltration equations. Performance of the sediment transport model was evaluated for bare and cropped furrow fields. The results indicated that the sediment transport model can predict the initial sediment rate adequately, but the simulated sediment rate was less accurate for the later part of the irrigation event. Sensitivity analysis of the parameters of the sediment module showed that the soil erodibility coefficient was the most influential parameter for determining sediment load in furrow irrigation. The developed modeling tool can be used as a water management tool for mitigating sediment loss from the surface irrigated fields.
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Swan, K. A., A. F. Severson, J. C. Carter, P. R. Martin, H. Schnabel, R. Schnabel, and B. Bowerman. "cyk-1: a C. elegans FH gene required for a late step in embryonic cytokinesis." Journal of Cell Science 111, no. 14 (July 30, 1998): 2017–27. http://dx.doi.org/10.1242/jcs.111.14.2017.
Full textAbstract:
A maternally expressed Caenorhabditis elegans gene called cyk-1 is required for polar body extrusion during meiosis and for a late step in cytokinesis during embryonic mitosis. Other microfilament- and microtubule-dependent processes appear normal in cyk-1 mutant embryos, indicating that cyk-1 regulates a specific subset of cytoskeletal functions. Because cytokinesis initiates normally and cleavage furrows ingress extensively in cyk-1 mutant embryos, we propose that the wild-type cyk-1 gene is required for a late step in cytokinesis. Cleavage furrows regress after completion of mitosis in cyk-1 mutants, leaving multiple nuclei in a single cell. Positional cloning and sequence analysis of the cyk-1 gene reveal that it encodes an FH protein, a newly defined family of proteins that appear to interact with the cytoskeleton during cytokinesis and in the regulation of cell polarity. Consistent with cyk-1 function being required for a late step in embryonic cytokinesis, we show that the CYK-1 protein co-localizes with actin microfilaments as a ring at the leading edge of the cleavage furrow, but only after extensive furrow ingression. We discuss our findings in the context of other studies suggesting that FH genes in yeast and insects function early in cytokinesis to assemble a cleavage furrow.
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Savoian, Matthew S., William C. Earnshaw, Alexey Khodjakov, and Conly L. Rieder. "Cleavage Furrows Formed between Centrosomes Lacking an Intervening Spindle and Chromosomes Contain Microtubule Bundles, INCENP, and CHO1 but Not CENP-E." Molecular Biology of the Cell 10, no. 2 (February 1999): 297–311. http://dx.doi.org/10.1091/mbc.10.2.297.
Full textAbstract:
PtK1 cells containing two independent mitotic spindles can cleave between neighboring centrosomes, in the absence of an intervening spindle, as well as at the spindle equators. We used same-cell video, immunofluorescence, and electron microscopy to compare the structure and composition of normal equatorial furrows with that of ectopic furrows formed between spindles. As in controls, ectopic furrows contained midbodies composed of microtubule bundles and an electron-opaque matrix. Despite the absence of an intervening spindle and chromosomes, the midbodies associated with ectopic furrows also contained the microtubule-bundling protein CHO1 and the chromosomal passenger protein INCENP. However, CENP-E, another passenger protein, was not found in ectopic furrows but was always present in controls. We also examined cells in which the ectopic furrow initiated but relaxed. Although relaxing furrows contained overlapping microtubules from opposing centrosomes, they lacked microtubule bundles as well as INCENP and CHO1. Together these data suggest that the mechanism defining the site of furrow formation during mitosis in vertebrates does not depend on the presence of underlying microtubule bundles and chromosomes or on the stable association of INCENP or CHO1. The data also suggest that the completion of cytokinesis requires the presence of microtubule bundles and specific proteins (e.g., INCENP, CHO1, etc.) that do not include CENP-E.
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Miller, A. L., R. A. Fluck, J. A. McLaughlin, and L. F. Jaffe. "Calcium buffer injections inhibit cytokinesis in Xenopus eggs." Journal of Cell Science 106, no. 2 (October 1, 1993): 523–34. http://dx.doi.org/10.1242/jcs.106.2.523.
Full textAbstract:
A slow cortical wave of high calcium accompanies the elongation of cleavage furrows in medaka fish eggs as well as in Xenopus eggs. We explored the role of such waves by injecting calcium buffers into Xenopus eggs at various times before and during first and second cleavage. Injection earlier than about 15 minutes before first cleavage normally starts delays it for hours. Injection between about 15 minutes and a few minutes before cleavage normally starts allows a (short) furrow to form on time but usually yields an eccentric one. This forms away from the injection side, often as far off-center as the egg's equator, and then regresses. Injection soon after it starts quickly arrests elongation of the furrow and eventually induces its regression; while injection a bit later likewise soon arrests elongation but allows delocalized furrow deepening to continue. The dependence of these inhibitory actions upon the dissociation constants and final cytosolic concentrations of the injected buffers indicates that they act as shuttle buffers to suppress needed zones of high calcium in the micromolar range. We conclude that the high calcium that is found within these furrows is needed to induce them, to extend them and even to maintain them. Moreover, while short, eccentric furrows often form as far off center as the equator, they somehow always form along a meridian through the animal pole. This seems difficult to explain by the orthodox, diastral model. Rather, it suggests that the cleavage furrows in Xenopus--and perhaps in animal cells quite generally--are directly induced by a diastema or telophase disc rather than by the asters.
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Riggs, Blake, Barbara Fasulo, Anne Royou, Sarah Mische, Jian Cao, Thomas S. Hays, and William Sullivan. "The Concentration of Nuf, a Rab11 Effector, at the Microtubule-organizing Center Is Cell Cycle–regulated, Dynein-dependent, and Coincides with Furrow Formation." Molecular Biology of the Cell 18, no. 9 (September 2007): 3313–22. http://dx.doi.org/10.1091/mbc.e07-02-0146.
Full textAbstract:
Animal cytokinesis relies on membrane addition as well as acto-myosin–based constriction. Recycling endosome (RE)-derived vesicles are a key source of this membrane. Rab11, a small GTPase associated with the RE and involved in vesicle targeting, is required for elongation of the cytokinetic furrow. In the early Drosophila embryo, Nuclear-fallout (Nuf), a Rab11 effector, promotes vesicle-mediated membrane delivery and actin organization at the invaginating furrow. Although Rab11 maintains a relatively constant localization at the microtubule-organizing center (MTOC), Nuf is present at the MTOC only during the phases of the cell cycle in which furrow invagination occurs. We demonstrate that Nuf protein levels remain relatively constant throughout the cell cycle, suggesting that Nuf is undergoing cycles of concentration and dispersion from the MTOC. Microtubules, but not microfilaments, are required for proper MTOC localization of Nuf and Rab11. The MTOC localization of Nuf also relies on Dynein. Immunoprecipitation experiments demonstrate that Nuf and Dynein physically interact. In accord with these findings, and in contrast to previous reports, we demonstrate that microtubules are required for proper metaphase furrow formation. We propose that the cell cycle–regulated, Dynein-dependent recruitment of Nuf to the MTOC influences the timing of RE-based vesicle delivery to the invaginating furrows.
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Jakobs, Inga, Oliver Schmittmann, Miriam Athmann, Timo Kautz, and Peter Schulze Lammers. "Cereal Response to Deep Tillage and Incorporated Organic Fertilizer." Agronomy 9, no. 6 (June 6, 2019): 296. http://dx.doi.org/10.3390/agronomy9060296.
Full textAbstract:
This study examined the effect of stripwise subsoiling and subsoiling combined with the incorporation of organic material on crop development in a two-year field trial with typical weather in the first year and hot, dry weather in the second. Subsoiling and its combination with incorporated organic materials had strong effects on plant development and crop yield of spring barley (2017) and winter wheat (2018). The subsoil was loosened in 30 cm wide furrows down to a depth of up to 60 cm with a tine (DL) or a spader machine (SM) and was compared with the same methods of subsoil loosening combined with the incorporation of compost from biological household wastes (DLB and SMB). Furthermore, green waste compost (SMG), chopped straw (SMCS) and sawdust (SMS) were incorporated with the spader machine only. DL successfully reduced penetration resistance underneath the furrow and enhanced root growth underneath and near the furrow over the whole experimental period. Grain protein content above the furrow was enhanced compared with the untreated control (C) in the first year, but grain yield did not increase. DLB also reduced penetration resistance and increased root growth, but furthermore caused considerable increases in soil mineral nitrogen underneath the furrow throughout the vegetation period. Consequently, both yield and grain protein content above the furrow were tendentially increased as compared with the C. In SMB, grain yield increased even more than in DLB, compared to C, in 2017 (84% for SMB vs. 19% for DLB) and nearly equally in 2018 (65.4% vs. 65.2%) while all other treatments tendentially decreased grain yield above the furrow as compared with C. The results indicate that subsoiling with the introduction of organic material can reduce mechanical impedance and increase soil nitrogen and thereby ensure stable yields during dry periods, which become more frequent under climate change.
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Afshar, K., B. Stuart, and S. A. Wasserman. "Functional analysis of the Drosophila diaphanous FH protein in early embryonic development." Development 127, no. 9 (May 1, 2000): 1887–97. http://dx.doi.org/10.1242/dev.127.9.1887.
Full textAbstract:
The Drosophila Formin Homology (FH) protein Diaphanous has an essential role during cytokinesis. To gain insight into the function of Diaphanous during cytokinesis and explore its role in other processes, we generated embryos deficient for Diaphanous and analyzed three cell-cycle-regulated actin-mediated events during embryogenesis: formation of the metaphase furrow, cellularization and formation of the pole cells. In dia embryos, all three processes are defective. Actin filaments do not organize properly to the metaphase and cellularization furrows and the actin ring is absent from the base of the presumptive pole cells. Furthermore, plasma membrane invaginations that initiate formation of the metaphase furrow and pole cells are missing. Immunolocalization studies of wild-type embryos reveal that Diaphanous localizes to the site where the metaphase furrow is anticipated to form, to the growing tip of cellularization furrows, and to contractile rings. In addition, the dia mutant phenotype reveals a role for Diaphanous in recruitment of myosin II, anillin and Peanut to the cortical region between actin caps. Our findings thus indicate that Diaphanous has a role in actin cytoskeleton organization and is essential for many, if not all, actin-mediated events involving membrane invagination. Based on known biochemical functions of FH proteins, we propose that Diaphanous serves as a mediator between signaling molecules and actin organizers at specific phases of the cell cycle.
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Crusciol, Carlos Alexandre Costa, André de Moraes Costa, Émerson Borghi, Gustavo Spadotti Amaral Castro, and Dirceu Maximino Fernandes. "Fertilizer distribution mechanisms and side dress nitrogen fertilization in upland rice under no-tillage system." Scientia Agricola 67, no. 5 (October 2010): 562–69. http://dx.doi.org/10.1590/s0103-90162010000500010.
Full textAbstract:
Some crops have shown not to adapt to the no-tillage system (NTS) as a consequence of the compaction of the superficial soil layer. In a certain way, the mechanism used in seeders to open furrows for the deposition of fertilizers can have great importance in facilitating root penetration. This study was carried out to evaluate the influence of two fertilizer distribution mechanisms and N fertilization in upland rice (Oryza sativa) under NTS. The experiment was carried out in the growing seasons 2001/2002 and 2002/2003, in Botucatu, state of São Paulo, Brazil. A completely randomized block design was applied, with subdivided plots and four replications. Main plots consisted of two furrow opening mechanisms (furrow opener and double disk). Subplots consisted of four side dressing N levels (0, 40, 80 and 120 kg ha-1). The following parameters were evaluated: furrow and seed deposition depth, plant population, plant height, number of stems and panicles m-2, number of spikelets per panicle, spikelet fertility, weight of 1,000 grains, shoot dry matter, grain yield and N levels in the flag leaf. The success for upland rice establishment under the NTS in dry winter regions of Brazil is directly associated to the furrow opening mechanism of the seed-drill. The furrow opener mechanism resulted in deeper seed deposition, consequently decreasing seedling population, number of panicles per area and grain yield. Side dressing N fertilization in upland rice under NTS increases grain yield whenever the double disk mechanism is used to sow.
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Jia, D. Y., X. L. Dai, H. W. Men, and M. R. He. "Assessment of winter wheat (Triticum aestivum L.) grown under alternate furrow irrigation in northern China: Grain yield and water use efficiency." Canadian Journal of Plant Science 94, no. 2 (March 2014): 349–59. http://dx.doi.org/10.4141/cjps2013-224.
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Jia, D.-Y., Dai, X.-L., Men, H.-W. and He, M.-R. 2014. Assessment of winter wheat (Triticum aestivum L.) grown under alternate furrow irrigation in northern China: Grain yield and water use efficiency. Can. J. Plant Sci. 94: 349–359. Increasing water use efficiency (WUE) can improve agricultural production in the north of China, where there is little or no prospect for the expansion of water resources. A field experiment was carried out to investigate the effects of alternate furrow irrigation (AFI) on the physiological response, grain yield, and WUE of winter wheat (Triticum aestivum L.) over two successive growing seasons (2009/2010 and 2010/2011). The irrigation regimes were: W0, non-irrigated; W2, every furrow was irrigated at jointing and anthesis; W3, every furrow was irrigated before wintering and at jointing and grain filling; and AFI, where one of the two neighboring furrows was alternately irrigated before wintering and at grain filling, and every furrow was irrigated during jointing. Our results indicate that the rate of plant transpiration and soil evaporation during grain filling were lower with AFI than when using W3. A reduced biological yield and increased harvest index were achieved under AFI compared with treatment W3. No difference in grain yield was observed between AFI and W3. The photosynthetic WUE, irrigation WUE, and WUE were all higher with AFI than with W3. Therefore, AFI is suggested as an appropriate irrigation schedule that achieves acceptable grain yields and allows for reductions in irrigation water consumption.
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Catsadorakis, Giorgos, Eleni Mougiakou, and Thanasis Kizos. "Ridge-and-Furrow Agriculture around Lake Mikri Prespa, Greece, in a European perspective." Journal of European Landscapes 2 (May 28, 2021): 7–20. http://dx.doi.org/10.5117/jel.2021.2.64206.
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Ridge and furrow is an archaeological pattern of ridges and troughs used in Europe, frequently associated with communal open-field farming and strip cultivation. Strip farming spread throughout Europe in the Middle Ages but appears to have only slightly penetrated southern Europe. In Greece, no areas under a ridge-and-furrow system were previously known. Working on 1945 aerial photos of Prespa, Greece, a border area around two lakes whose water levels fluctuate seasonally, we noted the presence of strip fields around the lakeshore, and subsequently identified them in the field as a ridge-and-furrow system. Using GIS, we measured the dimensions of all individual fields and collected oral histories from elderly locals. The area under strip farming was over 900 ha. Strips were straight, ca 200 m long and 10m wide, with a mean area of 2,160 m2. Wheat, rye, maize and beans were cultivated on the ridges, whilst grass in the furrows was mowed for hay. The construction and dimensions were almost identical to those seen in England. No information was found on either the origin of this system in Prespa, or connections with ‘zadruga’ or ‘chiftlik’ – other regional communal land management systems. A few adjacent areas with strip cultivations still in use were located in the two neighbouring countries sharing the lakes, and still fewer areas with ridge-and-furrow traces, particularly around lakes. By using ridge-and-furrow agriculture, local people had successfully coped with the perennial and seasonal inundation of their fields, a problem that remains unresolved and afflicts modern biodiversity conservation in the area.
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Wakelin-King, Gresley. "Using geomorphology to assess contour furrowing in western New South Wales, Australia." Rangeland Journal 33, no. 2 (2011): 153. http://dx.doi.org/10.1071/rj10080.
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This study examines landscape rehabilitation treatments installed 20–40 years ago in the Western Catchment of NSW. Treatment outcomes were assessed using geomorphic criteria, because geomorphic processes are fundamental to ecological permanence. Contour furrowing creates artificial runoff-runon sets which intercept runoff (resistance to flow by windrows microrelief and surface roughness) and promote infiltration (artificial permeability by ripping). As originally conceived, after windrows subside, flow resistance would be afforded by surface roughness under belts of vegetation. This study shows that rehabilitation treatments have a more complex relationship with the landscape than this would suggest, and that the final effect of the treatment depends on the geomorphic processes natural to the site. Treatment design should therefore be site-specific. The relevant aspects of treatment design are site location, runoff : runon ratio (expressed as furrow spacing and furrow length), furrow placement, and post-treatment management. Some long-term successes are documented. In ironstone ridge country affected by impermeable hard-setting soils, furrowing creates artificial permeability, allowing plant germination; plant material in the soil reverses hard-setting and establishes self-sustaining permeability. In stony gilgai country furrowing through vegetated patches can aid in re-establishing vegetation, but furrowing through stony runoff patches only diminishes, rather than improves, landscape function. Other landscape types will have different key attributes. In all cases, selection of appropriate sites for rehabilitation treatment is of primary importance. The 1990s NSW Soil Conservation Service best-practice included a specialised furrower, surveying techniques for accurate furrow placement along the contour, staggered gaps along each furrow line to reduce risks of gullying by windrow breakthrough, and post-treatment management of total grazing pressure. New guidelines for treatment design developed from this study include determining for each site the optimum runoff:runon ratio (which varies according to climate, gradient, vegetation, and regolith), and matching furrow spacing and furrow/gap length to local runoff:runon ratios. In stony gilgai country, furrow placement should be along the contour but within non-stony patches; elsewhere, placement should be rigorously along the contour. In ironstone ridge country, a greater runoff:runon ratio, commensurate with the area’s apparently larger patch scale, can be achieved by having more gap than furrow along each furrow line. No single rehabilitation technique will fit all landscape types, and these guidelines will ideally be developed further with investigation of other landscapes.
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Sahota, T. S., M. S. Virk, and P. M. Govindakrishnan. "Spot ν. furrow placement of phosphorus in potato at shillong." Journal of Agricultural Science 111, no. 1 (August 1988): 191–92. http://dx.doi.org/10.1017/s0021859600083015.
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Water soluble P fertilizers have been reported to be best for potato (Mattingly, 1963; Sharma, Grewal & Sud, 1976). However, they are irretrievably fixed in the acid soils because of their high P fixation capacity. Placement of P fertilizers is, therefore, necessary for their efficient use. Furrow placement of P fertilizers reduces their contact with soil and enhances P availability to the plants. Placement of P in spots, rather than in furrows, will further reduce the contact between the soil and the fertilizers and may improve its efficiency over furrow placement. The present investigation was undertaken to study the relative efficiency of these two methods of P application for potato in the spring season.
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Jurik, Thomas W. "Microtopography, Microenvironments, and Weed Populations in Ridge-Tilled Soybean." Weed Technology 20, no. 3 (September 2006): 593–604. http://dx.doi.org/10.1614/wt-05-015r1.1.
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The effects of microtopographic position on soil microenvironment and weed populations in ridge-tilled soybean were evaluated on three farms in Iowa in 1989 and 1990. In both years, over all weed species (primarily giant foxtail, green foxtail, yellow foxtail, redroot pigweed, and Pennsylvania smartweed), seedling emergence was highest in late May and early June, with few seedlings emerging after mid-June. Weed populations were highest in May and early June, after which rotary hoeing and cultivation reduced weed numbers in all plots. Microtopographic position (row, shoulder, and furrow) had a large effect on soil microenvironment and weed populations. Furrows were the wettest position through most of the growing season. Rows were the warmest position early in the season and the coolest position late in the season. Cumulative weed emergence early in the season was closely related to growing degree days, which accumulated faster in the row position than the furrow position. Following rotary hoeing and cultivation, the row position had significantly more total weeds than the shoulder and furrow positions on all farms in August of both years.
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Foldager, Frederik, Johanna Pedersen, Esben Skov, Alevtina Evgrafova, and Ole Green. "LiDAR-Based 3D Scans of Soil Surfaces and Furrows in Two Soil Types." Sensors 19, no. 3 (February 6, 2019): 661. http://dx.doi.org/10.3390/s19030661.
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Soil surface measurements play an important role in the performance assessment of tillage operations and are relevant in both academic and industrial settings. Manual soil surface measurements are time-consuming and laborious, which often limits the amount of data collected. An experiment was conducted to compare two approaches for measuring and analysing the cross-sectional area and geometry of a furrow after a trailing shoe sweep. The compared approaches in this study were a manual pinboard and a Light Detection and Ranging (LiDAR) sensor. The experiments were conducted in coarse sand and loamy sand soil bins exposed to three levels of irrigation. Using the LiDAR, a system for generating 3D scans of the soil surface was obtained and a mean furrow geometry was introduced to study the geometrical variations along the furrows. A comparison of the cross-sectional area measurements by the pinboard and the LiDAR showed up to 41% difference between the two methods. The relation between irrigation and the resulting furrow area of a trailing shoe sweep was investigated using the LiDAR measurements. The furrow cross-sectional area increased by 11% and 34% under 20 mm and 40 mm irrigation compared to non-irrigated in the coarse sand experiment. In the loamy sand, the cross-sectional area increased by 17% and 15% by irrigation of 20 mm and 40 mm compared to non-irrigated measured using the LiDAR.
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A.A., Terpigorev, and Zverkov M.S. "The basic methods of rational justification elements of the technology of surface irrigation by furrows." Ekologiya i stroitelstvo 2 (2017): 25–30. http://dx.doi.org/10.35688/2413-8452-2017-02-004.
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One of the main tasks in mechanized surface irrigation is to ensure the uniformity of distribution of irrigation norms along the length of the furrow, reducing the limit of discharges and reducing water losses to deep spillage. The magnitude of the technical elements of furrow irrigation is prescribed on the basis of permeability of soils, slope of the field surface, the value of irrigation norms to create the moisture reserves in the calculation of the soil, determining the development of the main mass of the root system of plants and technologies of their cultivation. Discusses various approaches to substantiation of rational elements of the technology of surface irrigation. Most appropriate to address the issue of rational justification of the elements of the technology of surface irrigation are the balance equations. Examples of balance equations based on the theory of infiltration absorption, developed by A.N. Kostyakova. Offered as possible solutions to the form of balance equations of water movement in a furrow and absorption of irrigation norms. It is expected that the dependence will simplify the approach to the assignment of rational parameters of elements of the mechanized watersaving furrow irrigation technology for specific production and economic conditions for ensuring the uniformity of soil moisture along the length of irrigation furrows not less 0.7...0.8 and justify the requirements to the technical means of irrigation.
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Neujahr, R., R. Albrecht, J. Kohler, M. Matzner, J. M. Schwartz, M. Westphal, and G. Gerisch. "Microtubule-mediated centrosome motility and the positioning of cleavage furrows in multinucleate myosin II-null cells." Journal of Cell Science 111, no. 9 (May 1, 1998): 1227–40. http://dx.doi.org/10.1242/jcs.111.9.1227.
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To study centrosome motility and the interaction of microtubules with the cell cortex in mitotic, post-mitotic and interphase cells, (alpha)-tubulin was tagged in Dictyostelium discoideum with green fluorescent protein. Multinucleate cells formed by myosin II-null mutants proved to be especially suited for the analysis of the control of cleavage furrow formation by the microtubule system. After docking of the mitotic apparatus onto the cell cortex during anaphase, the cell surface is activated to form ruffles on top of the asters of microtubules that emanate from the centrosomes. Cleavage furrows are initiated at spaces between the asters independently of the positions of spindles. Once initiated, the furrows expand as deep folds without a continued connection to the microtubule system. Occurrence of unilateral furrows indicates that a closed contractile ring is dispensable for cytokinesis in Dictyostelium. The progression of cytokinesis in the multinucleate cells underlines the importance of proteins other than myosin II in specifying a cleavage furrow. The analysis of centrosome motility suggests a major role for a minus-end directed motor protein, probably cytoplasmic dynein, in applying traction forces on guiding microtubules that connect the centrosome with the cell cortex.
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Li, Q. Q., X. B. Zhou, Y. H. Chen, and S. L. Yu. "Grain yield and quality of winter wheat in different planting patterns under deficit irrigation regimes." Plant, Soil and Environment 56, No. 10 (October 20, 2010): 482–87. http://dx.doi.org/10.17221/14/2010-pse.
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Limited water resources restrict winter wheat grain yield and quality in the Huang-Huai-Hai Plain of North China, and establishing optimal planting patterns according to crop water requirements is the key factor for achieving rational water use. In this paper, 4 planting patterns were applied, namely, uniform row (30 cm; traditional pattern), wide (40 cm)-narrow (20 cm) row, furrow (double lines in the furrow with 20 cm spacing, and 40 cm between furrows), and seed bed (double lines on the bed with 20 cm spacing, and 40 cm between beds). Each planting pattern was irrigated twice during the jointing and heading stages, and total irrigation water was controlled at 120 mm. Grain yield was significantly (LSD, P < 0.05) higher in the furrow planting pattern than in the uniform row, wide-narrow row, and seed bed planting patterns, by 73.4, 64.3, and 53.4 g/m<sup>2</sup>, respectively, in 2004–2005 and by 54.3, 42.6, and 30.2 g/m<sup>2</sup>, respectively, in 2005–2006, mainly because of a significant (LSD, P < 0.05) increase in the spike and kernel numbers. These results were caused by changes in the contribution of dry matter remobilization to grain yield (CDMRG); the CDMRG was higher in the furrow planting pattern than in the uniform row, wide-narrow row, and seed bed planting patterns by 5.1%, 4.3%, and 2.9%, respectively. Gliadin and glutenin contents in the furrow planting pattern were 4.67% and 5.85%, respectively, and were significantly (LSD, P < 0.05) higher than those in the uniform row, wide-narrow row, and seed bed planting patterns; however, the furrow planting pattern had no significant (LSD, P < 0.05) effect on albumin and globulin contents. Dough development time (DDT) and dough stable time (DST) in the furrow planting pattern were 5.6 min and 8.8 min, respectively; they were significantly (LSD, P < 0.05) improved compared to those in the uniform row, wide-narrow row, and seed bed planting patterns; however, there were no significant (LSD, P < 0.05) differences in dough breakdown time (DBT) between any of the planting patterns. These results suggest that the furrow planting pattern combined with deficit irrigation during the jointing and heading stages can be applied to winter wheat production in the Huang-Huai-Hai Plain of North China.
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Trout, Thomas J. "Furrow Geometric Parameters." Journal of Irrigation and Drainage Engineering 117, no. 5 (September 1991): 613–34. http://dx.doi.org/10.1061/(asce)0733-9437(1991)117:5(613).
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Glotzer, Michael. "Cleavage furrow positioning." Journal of Cell Biology 164, no. 3 (February 2, 2004): 347–51. http://dx.doi.org/10.1083/jcb.200310112.
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To complete the cell cycle, the cleavage furrow draws the plasma membrane toward the cell center, pinching the cytoplasm into two lobes that are subsequently separated into two cells. The position of the cleavage furrow is induced by the mitotic spindle during early anaphase. Although the mechanism of cleavage furrow positioning is not understood at a molecular level, recent results suggest that it might be mediated by local relief from the inhibitory effects of microtubules.
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Hanson, Blaine R., Terry L. Prichard, and Herbert Schulbach. "Estimating furrow infiltration." Agricultural Water Management 24, no. 4 (December 1993): 281–98. http://dx.doi.org/10.1016/0378-3774(93)90008-x.
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Tabatabaei, Seyed Mahmoud, and Rasoul Asadi. "Estimation of Infiltration Parameters and Manning Roughness with SIPAR_ID Software." International Journal of Life Sciences 9, no. 5 (June 14, 2015): 70–74. http://dx.doi.org/10.3126/ijls.v9i5.12700.
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Estimation of infiltration parameters is very difficult in furrow irrigation while they have very important effect in design and evaluation of surface irrigation systems. There are different methods for estimating infiltration parameters based on mathematical models such as SIPAR_ID model. SIPAR_ID model uses inverse solution to estimation of infiltration parameters and manning roughness. The objective of this study is to evaluate these models to estimate infiltration parameters in furrow irrigation. The study consisted of field experiments and numerical simulation. Field experiments were conducted in Zarand district of Iran in April 2012. Infiltration parameters and Manning roughness values were estimated with SIPAR_ID software. The estimated values were put into the WinSRFR software, and then the advance trajectory, flow depths in the upstream, and irrigation performance were simulated on each test furrow. The results showed that the simulated values with the WinSRFR software were in excellent agreement with the measured data. Therefore, the infiltration parameters and manning roughness estimated with SIPAR_ID software were reliable. Also that adequate and efficient irrigation can be obtained using closed-end furrows through a proper selection of inflow discharge and cutoff time.DOI: http://dx.doi.org/10.3126/ijls.v9i5.12700