2,990 research outputs found
A comparison of manual and automatic moth sampling methods (Lepidoptera : Arctiidae, Geometridae) in a rain forest in Costa Rica
No full textSampling with UV fluorescent light tubes is a commonly used technique both in applied and basic insect studies. Our study compares the performance of two such methods: manual sampling (light towers) and automatic sampling (funnel light traps). The abundance, diversity, and body size of moths representing two species-rich families (Lepidoptera: Arctiidae, Geometridae) were analyzed in a lowland rain forest in Costa Rica (La Selva Biological Station, 10.4 degrees N, 84.0 degrees W) during 2003 and 2004. Light towers were equipped with two 15-W UV fluorescent tubes and were operated for 3 h in 16 nights. Traps equipped with single 8-W fluorescent tubes were run throughout 20 nights in the understory of the forest. In addition, parallel trap sampling was carried out in the canopy. A total of 1,238 arctiid moths representing 162 species and 1,769 geometrid moths representing 196 species were collected. In Geometridae, tower samples were significantly larger than trap samples. Towers also attracted a higher overall number of species. Very small geometrids (particularly of the subfamily Sterrhinae) were under-represented in trap samples, suggesting that this method is biased toward larger species. In arctiid moths, there were no significant differences in either the sample sizes, the number of species or in the size of the individuals sampled. Diversity calculated as Fisher's a was similar for towers and understory traps in both families. A major component of diversity was added with canopy trap samples for arctiid moths, but not for geometrid moths. In conclusion, ground-based tower sampling proved to be the most suitable method for geometrid moths, and trap sampling including both understory and canopy for arctiid moths. For full moth species inventories, a combination of both approaches is recommended
Improving the pollinator pantry: Restoration and management of open farmland ponds enhances the complexity of plant-pollinator networks
No full textIn line with general biodiversity losses across agricultural landscapes, insect pollinators have experienced recent sharp declines. A range of conservation measures have been developed to address these declines, with plant-pollinator interaction networks providing key insights into the effectiveness of these measures. For the first time, we studied interactions between three diurnal pollinator groups (bees, hoverflies, and butterflies) and insect-pollinated plants to understand how they are affected by pond management and restoration. Major network contributors were identified, and important network-level parameters compared at nine farmland ponds under different management strategies to assess management effects on plant-pollinator interactions: three ‘overgrown’ tree-covered ponds, three ‘long-term managed ponds’ kept in an open-canopy, early- to mid-successional state by periodic interventions involving tree and sediment removal, and three ‘recently restored ponds’, initially heavily overgrown with woody vegetation, and subsequently rapidly transformed into an early succession state through major tree and sediment removal. Interaction complexity, as measured by the metrics ‘links per species’, ‘linkage density’, Fisher’s alpha and Shannon’s Diversity, was higher for both long-term managed and recently restored ponds compared to overgrown ponds. Several network-level parameters indicated that highest complexity levels were found at recently restored ponds due to their substantially higher plant diversity. Bipartite interaction analysis suggests major benefits of pond management and restoration for agricultural pollinator assemblages. We strongly advocate the inclusion of ponds in conservation strategies and policies aimed at pollinators - ponds should be part of the pollinator pantry
Perancangan Sistem Informasi Pengelola Barang/Inventaris Di Jc Komp
No full textInventory information system is a system used to enter inventory data into the database, so that there are no errors in input, output data, and reporting based on the desired data. based on surveys and interviews with jc comp personnel, information was obtained that the existing system in the jc comp warehouse section is still manual. therefore, the system that will be created by the author is the result of a replication of the existing system in the jc comp warehouse section. in addition to the process of input and output of goods, this information system is also equipped with features for creating data reports, input and output of goods, and searching for goods data by item name. with the inventory information system is expected to be useful for the warehouse parts jc comp. By implementing this system in the jc comp warehouse, it is hoped that it can reduce errors that may occur. this system is also expected to further speed up the process of input, output, and report generation, which in turn will help the jc comp warehouseSistem Informasi Persediaan Barang adalah sebuah sistem yang digunakan untuk memasukkan data-data persediaan barang ke dalam database, sehinggga tidak terjadi kesalahan dalam input, output data, dan pembuatan laporan berdasarkan data yang diinginkan. Berdasarkan survey dan wawancara dengan bagian personalia Jc Komp, didapatkan informasi bahwa sistem yang ada dibagian gudang Jc Komp masih manual. Oleh karena itu, sistem yang akan dibuat oleh penulis adalah hasil replikasi dari sistem yang telah ada dibagian gudang Jc Comp. Selain proses input dan output barang, pada sistem informasi ini juga dilengkapi fitur pembuatan laporan data, input, dan output barang, dan pencarian data barang berdasarkan nama barang. Dengan adanya Sistem Informasi persediaan barang ini diharapkan dapat bermanfaat bagi bagian gudang Jc Komp. Dengan diterapkannya sistem ini pada bagian gudang Jc Comp, maka diharapkan dapat mengurangi kesalahan-kesalahan yang mungkin terjadi. Sistem ini juga diharapkan dapat lebih mempercepat proses input, output, dan pembuatan laporan yang pada akhirnya dapat membantu bagian gudang Jc Komp
“The pond pollinator pantry”: Assessing how pond management influences pollinators in the UK farmland landscape
No full textRecent decades have seen major declines in invertebrate populations across agricultural landscapes, especially amongst pollinating insects. Concurrently, farmland ponds have faced ecological degradation through neglect and ecological succession leading to the widespread development of heavily overgrown and species-poor systems. Recent research has shown ponds to be highly beneficial to pollination, but the mechanisms that connect ponds to pollinating invertebrate species are poorly understood. Similarly, little is known on how the restoration and subsequent management of formerly overgrown farmland ponds impacts upon pollinating insect communities, and whether current pond restoration techniques, involving major woody vegetation removal, mimic what is believed to have occurred at farmland ponds in the past. In this thesis, I examine the drivers of pollinator utilisation of farmland pond systems based on the presence of woody vegetation management, as well as examining historical changes to ponds ecosystems as a means to informing on past pond-plant-pollinator environments and the influence of historic management practices relative to contemporary UK pond restoration approaches. First, I studied the effects of occasional tree and shrub management and pond restoration on flowering plant communities. Influences of pond management on diurnal and nocturnal pollinator richness and abundance were then explored with the general conclusion that such efforts were largely beneficial. Indeed, enhanced flowering plant and pollinator communities also resulted in increased complexity in terms of plant-pollinator interactions. Finally, subfossil analysis of pond sediment cores indicated that current woody vegetation management has historical precedents in the past, with restored pond macrophyte communities having close similarities with subfossil assemblages. With farmland ponds scattered widely across UK farmland landscapes, their conservation represents a massive, untouched resource in the preservation of historical wetland plant and pollinating insect communities
Amenable L-2-Theoretic Methods and Knot Concordance
No full textWe reveal new structures in the topological knot concordance group. As a key ingredient, we develop obstructions using L-2-theoretic methods for amenable groups in Strebel's class recently introduced by Orr and the author. Concerning (h)-solvable knots, which are defined in terms of certain Whitney towers of height h in bounding 4-manifolds, we show the following: for any n>1, there are (n)-solvable but non-(n. 5)-solvable (and therefore nonslice) knots, which are not detected by prior methods using Cochran-Orr-Teichner L-2-signature obstructions as well as Levine algebraic obstructions and Casson-Gordon invariants.X1197sciescopu
Dynamics of Network Formation Processes in the Co-Author Model
No full textThis article studies the dynamics in the formation processes of a mutual consent network in game theory setting: the Co-Author Model. In this article, a limited observation is applied and analytical results are derived. Then, 2 parameters are varied: the number of individuals in the network and the initial probability of the links in the network in its initial state. A simulation result shows a finding that is consistent with an analytical result for a state of equilibrium while it also shows different possible equilibria.Dynamics, Network, Game Theory, Model,Simulation, Equilibrium, Complexity
High-level polyomavirus JC viruria following long-term steroid therapy
No full textCASE REPORT JC virus is a highly seroprevalent ubiquitous polyomavirus which is acquired at an early age through respiratory or oral route, Thereafter JCV establishes persistent, but mainly asymptomatic, infections in various tissues, including the genitourinary tract and brain Corresponding author Cristina Costa, MD S.C.D.U. Virologia Azienda Ospedaliero-Universitaria San Giovanni Battista di Torino Via Santena, 9 -10126 Torino E-mail: [email protected] increasing with age, with adult prevalence rate often between 15% and 60
Engineering Framework to Utilize Miniaturized Charpy Type SE(B) Specimens to Predict Jc of Full Sized Specimens
No full textAbstractThis paper introduces our experience of using miniature Charpy type SE(B) specimen in obtaining fracture toughness Jc of a material in the ductile to brittle transition temperature (DBTT) region. Width W x thickness B of 2 x 2 mm, 3 x 3 mm and 10 x 10 mm were chosen as miniature specimens and 25 x 25 mm were chosen as full sized specimen. 0.55% carbon steel JIS S55C, whose tensile to yield stress ratio σTS/σYS was equal to 1.8 was chosen as a material to simulate a degraded (embrittled) material in the DBTT region. Focus was placed on whether cleavage fracture could be predicted for these miniaturized specimens. Another focus was placed on whether the Jc of full sized specimen is predictable from the test results of the miniature sized specimens, in case cleavage fracture were observed. The results showed that the modified Ritch-Knott-Rice (RKR) failure criterion (which predicts the onset of cleavage fracture when the crack opening stress measured at 4 times the crack-tip opening displacement exceeds this σ22c) could predict whether cleavage fracture would occur or not. Another finding was that, in case cleavage fracture was observed though, the critical value σ22c in the modified RKR failure criterion was independent of specimen size, and thus, Jc of the full sized specimen is predictable from the miniature specimen test results, though M = (W-a)σYS/Jc was smaller than ASTM E1921 requirement of 30. Here, a and σYS are crack length and yield strength, respectively
Biogeochemistry of an afrotropical montane rain forest on Mt. Kilimanjaro, Tanzania
No full textIn contrast to their well-studied counterparts in the Neotropics and in Asia, East African montane rain forests are surrounded by semi-arid savanna plains. These plains have a high erosion potential for salt crusts accumulated at the soil surface. Hence it may be hypothesized that East African montane forest ecosystems experience strongly enhanced nutrient inputs via dry deposition, which alters their overall biogeochemistry. The aim of our study was to test this hypothesis by investigating K, Mg, Ca, Na and N-forms in rainfall, throughfall, fine litter, litter percolate and soil solution of a montane rain forest at Mt. Kilimanjaro. Four forest plots situated at elevations between 2250 and 23 50 in asl on the south-western slopes of Mt. Kilimanjaro were studied for 2 y. In contradiction to our hypothesis, inputs of K, Mg, Ca and Na via rainfall (7.5, 0.9, 2.3 and 6.2 kg ha(-1) y(-1)) and throughfall (3 5, 2.0, 3.5 and 11 kg ha(-1) y(-1)) were low on Mt. Kilimanjaro. Fluxes of NH4-N and NO3-N were within the range observed at other montane rain forests. with NO3-N being the only nutrient partly absorbed in the forest canopies (2.9 kg ha(-1) y(-1) in rainfall, 0.9 kg ha(-1) y(-1) in throughfall). The highest overall nutrient concentrations in water samples occurred in litter percolate (1.4 mg l(-1) K, 0.3 mg l(-1) Mg, 0.8 mg l(-1) Ca, 0.3 mg l(-J) NH4-N, 0.9 mg l(-1) NO3-N), with values still being low compared to other sites. Nutrient concentrations in seepage water strongly declined with increasing soil depth. Thus, both inputs and losses of base cations from the forest by water pathways are assumed to be low. N or P limitation of growth is not expected since high fluxes of N and P in fine litter (119 and 5.9 kg ha(-1) y(-1) for N and P respectively) indicate low within-stand efficiency
Manual versus automatic moth sampling at equal light sources – a comparison of catches from Mt. Kilimanjaro.
No full textNocturnal moth ensembles are frequently assessed using either catches from automatic light traps or manually collected samples at artificial light sources. Up to now, Few studies have compared the influence of these methodological differences on the samples. We compared such samples, attracted by identical light sources , using geometrid moths in the montane rainforest belt of Mt. Kilimanjaro, Tanzania, as an example. The average number of moths caught manually from 1900 h to 2200 h at a light tower - a reflective gauze cylinder with a lamp placed in the middle - was more than ten times higher than that caught in a light trap, with more than half of all spccies only recorded at the light tower. With regard to individuals sampled, catches were biased towards the subfamily Ennorninac in the traps (.51 % versus 30%) and towards Larentiinae in the manual samples (68% versus 44%). It remains to be tested whether the relatively higher representation of larger-sized Ennominae in the trap catches is due to later flight activity m SOlne behavioral differences related to body size. Diversity (measured as Fisher's alpha) oT light tower catches decreased from clearings (22.4) and secondary forest (21.7) to mature forest (11.0), whjle in the traps, values increased in the same order (Fisher's alpha: 6.0, 12.0, and 14.2). Species composition of trap samples taken in clearings and secondary forcst differed strongly from manual catches, while manual and automatic samples from mature forest were more similar to each other. Manual moth sampling at light towers proved superior to automatic light traps in many ways and is hence recommended as a very useful standard method to record nocturnal inseds if sufficient man-power is available
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