Analisis Tingkat Berpikir Geometri Siswa Menurut Teori van Hiele Ditinjau dari Gaya Belajar

Penelitian ini bertujuan untuk mendeskripsikan tingkat berpikir geometri siswa menurut teori van Hiele ditinjau dari gaya belajar. Jenis penelitian ini adalah deskriptif kuantitatif. Sampel penelitian yaitu siswa kelas IX A, IX B, dan IX C SMPN 7 Mataram tahun pelajaran 2022/2023 yang dipilih menggunakan teknik cluster random sampling. Instrumen penelitian yang digunakan adalah angket gaya belajar dan tes tingkat berpikir geometri van Hiele. Teknik analisis data yang digunakan meliputi teknik analisis data angket gaya belajar dan teknik analisis data tes tingkat berpikir geometri van Hiele. Hasil penelitian menunjukkan bahwa gaya belajar yang dominan dimiliki oleh siswa adalah gaya belajar auditorial dibandingkan dengan gaya belajar visual dan kinestetik. Siswa dengan gaya belajar visual dan auditorial berada pada tingkat 1 (analisis). Siswa dengan gaya belajar visual dan auditorial sudah mampu mengidentifikasi suatu bangun ruang sisi datar berdasarkan karakteristik visualnya, mampu menentukan sifat-sifat suatu bangun ruang sisi datar dan kesamaan sifat beberapa bangun ruang sisi datar. Siswa dengan gaya belajar kinestetik berada pada tingkat 0 (visualisasi). Siswa dengan gaya belajar kinestetik sudah mampu mengidentifikasi suatu bangun ruang sisi datar berdasarkan karakteristik visualnya

Value of useful goods and ecosystem services from Agnalavelo sacred forest and their relationships with forest conservation

ABSTRACTAgnalavelo forest provides necessary natural resources to people who live in its surroundings (Communities of Mahaboboka, Amboronabo and Mikoboka in southwestern Madagascar). The aim of this study is to document goods and ecosystem services provided by Agnalavelo forest to local people and to use it as a tool for the identification of priorities for forest conservation. Oral interviews were undertaken from 2010–2013 with local communities living in the vicinity of Agnalavelo forest. This study also investigated forest resource use, conducted inventories of tree species, estimated wood biovolume, as well as the economic benefits associated with conservation due to carbon storage. Finally, we recorded felled trees caused by honey collection inside the forest and determine the cause for their slaughter. An investigation with the ownership of rice fields irrigated by rivers taking sources from Agnalavelo forest was also conducted. Based on field surveys and analysis, communities living around Agnalavelo forest draw substantial benefits for their daily life from the forest. Goods and ecosystem services are classified in the three categories (provisioning, cultural and regulating services) according to the Millennium Ecosystem Assessment (MEA). Cultural services are highly valuable to local people as the forest is a dwelling place for their ancestor’s spirits. Agnalavelo forest provides Non Wood Forest Products (NWFPs) such as foods, tools, magic and medicinal plants and fresh water for local people. It is able to store 152 tons of carbon per hectare which is very important for climate regulation in this dry southwestern part of Madagascar. Endemic tree species hosting bee hives are often felled during harvesting period. Agnalavelo forest conservation is very important not only with regards to its biodiversity but also for goods and services that it provides to local population.RÉSUMÉLa forêt d’Agnalavelo, sur les communes de Mahaboboka, Amboronabo et Mikoboka, au sud-ouest de Madagascar, fournit les ressources naturelles nécessaires pour la population riveraine. L’objectif de cette étude a été de documenter les biens et les services éco-systémiques fournis par la forêt d’Agnalavelo pour les populations locales, afin d’identifier les priorités pour la conservation de cette forêt. Des enquêtes auprès des communautés vivant à proximité de la forêt Agnalavelo ont été menées, entre 2010 et 2013, sur l'utilisation des ressources forestières. Des inventaires écologiques des espèces d'arbres forestiers utilisés ont été réalisés pour déterminer le biovolume ainsi que les bénéfices économiques associés à la conservation de la forêt d’Agnalavelo par le stockage de carbone. Un inventaire des arbres abattus le long d'une piste forestière et les causes de leurs abattages ont complété l’étude, ainsi que des enquêtes auprès des propriétaires des rizières irriguées par les rivières qui prennent leurs sources dans la forêt d’Agnalavelo qui ont révélé que les communautés riveraines en tirent profit dans leur quotidien. La forêt d’Agnalavelo offre trois catégories de biens et services écosystémiques, à savoir les services d’approvisionnement, les services culturels et les services de régulation. Les services culturels sont les plus importants pour la population locale. La forêt d’Agnalavelo fournit les produits forestiers non ligneux tels que de la nourriture, des outils, des plantes considérées comme magiques, des plantes médicinales et de l'eau douce pour la population locale. La forêt d’Agnalavelo peut stocker 152 tonnes de carbone par hectare, valeur importante pour la régulation du climat dans cette région sèche de Madagascar. Des arbres appartenant à des espèces endémiques de Madagascar et abritant des ruches sont souvent abattus lors de la récolte du miel. La conservation de la forêt d’Agnalavelo est importante aussi bien pour la biodiversité qu’elle héberge que pour les biens et services des écosystèmes qu'elle fournit à la population locale

Nut production in Bertholletia excelsa across a logged forest mosaic: implications for multiple forest use

Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù

Aneurysmal disease is associated with lower carotid intima-media thickness than occlusive arterial disease

Objective: Patients with aneurysmal and occlusive arterial disease have overlapping cardiovascular risk profiles. The question remains how atherosclerosis is related to the formation of aortic aneurysms. Common carotid artery intima-media thickness (CIMT) is an easily accessible and objective marker of early atherosclerosis. The aim of the current study was to investigate whether there is a difference in atherosclerotic burden as measured by CIMT between patients with aneurysmal and those with occlusive arterial disease. Methods: From 2004 to 2011, the CIMT was measured using B-mode ultrasound scanning in patients undergoing vascular surgery for aortic aneurysmal or occlusive arterial disease at the Erasmus University Medical Center. Cardiovascular risk factors, comorbidities, and medication were recorded. Patients treated for combined aneurysmal and occlusive arterial disease and patients diagnosed with a genetic aneurysm syndrome were excluded. Univariable and multivariable analyses wer

Phenotype Fingerprinting Suggests the Involvement of Single-Genotype Consortia in Degradation of Aromatic Compounds by Rhodopseudomonas palustris

Anaerobic degradation of complex organic compounds by microorganisms is crucial for development of innovative biotechnologies for bioethanol production and for efficient degradation of environmental pollutants. In natural environments, the degradation is usually accomplished by syntrophic consortia comprised of different bacterial species. This strategy allows consortium organisms to reduce efforts required for maintenance of the redox homeostasis at each syntrophic level. Cellular mechanisms that maintain the redox homeostasis during the degradation of aromatic compounds by one organism are not fully understood. Here we present a hypothesis that the metabolically versatile phototrophic bacterium Rhodopseudomonas palustris forms its own syntrophic consortia, when it grows anaerobically on p-coumarate or benzoate as a sole carbon source. We have revealed the consortia from large-scale measurements of mRNA and protein expressions under p-coumarate, benzoate and succinate degrading conditions using a novel computational approach referred as phenotype fingerprinting. In this approach, marker genes for known R. palustris phenotypes are employed to determine the relative expression levels of genes and proteins in aromatics versus non-aromatics degrading condition. Subpopulations of the consortia are inferred from the expression of phenotypes and known metabolic modes of the R. palustris growth. We find that p-coumarate degrading conditions may lead to at least three R. palustris subpopulations utilizing p-coumarate, benzoate, and CO2 and H2. Benzoate degrading conditions may also produce at least three subpopulations utilizing benzoate, CO2 and H2, and N2 and formate. Communication among syntrophs and inter-syntrophic dynamics in each consortium are indicated by up-regulation of transporters and genes involved in the curli formation and chemotaxis. The N2-fixing subpopulation in the benzoate degrading consortium has preferential activation of the vanadium nitrogenase over the molybdenum nitrogenase. This subpopulation in the consortium was confirmed in an independent experiment by consumption of dissolved nitrogen gas under the benzoate degrading conditions

Acidithiobacillus ferrooxidans metabolism: from genome sequence to industrial applications

<p>Abstract</p> <p>Background</p> <p><it>Acidithiobacillus ferrooxidans </it>is a major participant in consortia of microorganisms used for the industrial recovery of copper (bioleaching or biomining). It is a chemolithoautrophic, γ-proteobacterium using energy from the oxidation of iron- and sulfur-containing minerals for growth. It thrives at extremely low pH (pH 1–2) and fixes both carbon and nitrogen from the atmosphere. It solubilizes copper and other metals from rocks and plays an important role in nutrient and metal biogeochemical cycling in acid environments. The lack of a well-developed system for genetic manipulation has prevented thorough exploration of its physiology. Also, confusion has been caused by prior metabolic models constructed based upon the examination of multiple, and sometimes distantly related, strains of the microorganism.</p> <p>Results</p> <p>The genome of the type strain <it>A. ferrooxidans </it>ATCC 23270 was sequenced and annotated to identify general features and provide a framework for <it>in silico </it>metabolic reconstruction. Earlier models of iron and sulfur oxidation, biofilm formation, quorum sensing, inorganic ion uptake, and amino acid metabolism are confirmed and extended. Initial models are presented for central carbon metabolism, anaerobic metabolism (including sulfur reduction, hydrogen metabolism and nitrogen fixation), stress responses, DNA repair, and metal and toxic compound fluxes.</p> <p>Conclusion</p> <p>Bioinformatics analysis provides a valuable platform for gene discovery and functional prediction that helps explain the activity of <it>A. ferrooxidans </it>in industrial bioleaching and its role as a primary producer in acidic environments. An analysis of the genome of the type strain provides a coherent view of its gene content and metabolic potential.</p

Going Deeper: Metagenome of a Hadopelagic Microbial Community

The paucity of sequence data from pelagic deep-ocean microbial assemblages has severely restricted molecular exploration of the largest biome on Earth. In this study, an analysis is presented of a large-scale 454-pyrosequencing metagenomic dataset from a hadopelagic environment from 6,000 m depth within the Puerto Rico Trench (PRT). A total of 145 Mbp of assembled sequence data was generated and compared to two pelagic deep ocean metagenomes and two representative surface seawater datasets from the Sargasso Sea. In a number of instances, all three deep metagenomes displayed similar trends, but were most magnified in the PRT, including enrichment in functions for two-component signal transduction mechanisms and transcriptional regulation. Overrepresented transporters in the PRT metagenome included outer membrane porins, diverse cation transporters, and di- and tri-carboxylate transporters that matched well with the prevailing catabolic processes such as butanoate, glyoxylate and dicarboxylate metabolism. A surprisingly high abundance of sulfatases for the degradation of sulfated polysaccharides were also present in the PRT. The most dramatic adaptational feature of the PRT microbes appears to be heavy metal resistance, as reflected in the large numbers of transporters present for their removal. As a complement to the metagenome approach, single-cell genomic techniques were utilized to generate partial whole-genome sequence data from four uncultivated cells from members of the dominant phyla within the PRT, Alphaproteobacteria, Gammaproteobacteria, Bacteroidetes and Planctomycetes. The single-cell sequence data provided genomic context for many of the highly abundant functional attributes identified from the PRT metagenome, as well as recruiting heavily the PRT metagenomic sequence data compared to 172 available reference marine genomes. Through these multifaceted sequence approaches, new insights have been provided into the unique functional attributes present in microbes residing in a deeper layer of the ocean far removed from the more productive sun-drenched zones above