Analysis of Mathematics National Exam Questions based on TIMSS Taxonomy

The purpose of this research was to find out the spread out content and cognitive dimension of the question of Mathematics National Exam for Junior High School (SMP) / Islamic Junior High School (MTs) in the school year of 2005/2006-2018/2019 and find out the suitability question of Mathematics Final Exam in Junior High School based on government guidelines and TIMSS taxonomy. This type of research is a qualitative approach. This research use collection data with document analysis. Data analysis techniques consist of data reduction, data display, and verification. The research subjects were in the form of 14 SMP / MTs national mathematics exam texts from the 2005/2006 to 2018/2019 academic year. The indicators of content dimensions and cognitive dimensions used are based on the TIMSS taxonomy. Checking the validity of the data, the researcher uses a triangulation by an expert through Online FGD (Focus Group Discussion).The research result as follows: 1. An analysis a question of Mathematics Final Exam in Junior High School in the school year of 2005/2006-2018/2019 based on a taxonomy TIMSS obtain results that percentage spread of content and cognitive dimension still not appropriate yet with TIMSS Assessment Framework. At the content dimension, the spread of a question dominated by geometry domain while data and probability have spread of a question very few. Then, algebra and number domain pretty close proportion which have been specified by TIMSS. 2. the question of Mathematics Final Exam in Junior High School to the scope of material which set by the government was not given percentage distribution of materials obviously while cognitive level from government obtains a result that different with findings result in the researcher based on TIMSS taxonomy because there is different definition at government cognitive level from with TIMSS cognitive domain. There is a question that includes an application in government cognitive level however it includes knowing domain based on TIMSS taxonomy. Suitability a question of Final Exam from the school year of 2005/2006 till 2018/2019 indicate there are percentages increase from year to year close appropriate to proportion TIMSS Assessment Framework. It shows the percentage each other domain close proportion TIMSS in content and cognitive dimension

Laboratory Investigation of Ice Formation and Elimination in the Induction System of a Large Twin-engine Cargo Aircraft

The icing characteristics, the de-icing rate with hot air, and the effect of impact ice on fuel metering and mixture distribution have been determined in a laboratory investigation of that part of the engine induction system consisting of a three-barrel injection-type carburetor and a supercharger housing with spinner-type fuel injection from an 18-cylinder radial engine used on a large twin-engine cargo airplane. The induction system remained ice-free at carburetor-air temperatures above 36 F regardless of the moisture content of the air. Between carburetor-air temperatures of 32 F and 36 F with humidity ratios in excess of saturation, serious throttling ice formed in the carburetor because of expansion cooling of the air; at carburetor-air temperatures below 32 F with humidity ratios in excess of saturation, serious impact-ice formations occurred, Spinner-type fuel injection at the entrance to the supercharger and heating of the supercharger-inlet elbow and the guide vanes by the warn oil in the rear engine housing are design features that proved effective in eliminating fuel-evaporation icing and minimized the formation of throttling ice below the carburetor. Air-flow recovery time with fixed throttle was rapidly reduced as the inlet -air wet -bulb temperature was increased to 55 F; further temperature increase produced negligible improvement in recovery time. Larger ice formations and lower icing temperatures increased the time required to restore proper air flow at a given wet-bulb temperature. Impact-ice formations on the entrance screen and the top of the carburetor reduced the over-all fuel-air ratio and increased the spread between the over-all ratio and the fuel-air ratio of the individual cylinders. The normal spread of fuel-air ratio was increased from 0.020 to 0.028 when the left quarter of the entrance screen was blocked in a manner simulating the blocking resulting from ice formations released from upstream duct walls during hot-air de-icing

Macrocyclic colibactin induces DNA double-strand breaks via copper-mediated oxidative cleavage.

Colibactin is an assumed human gut bacterial genotoxin, whose biosynthesis is linked to the clb genomic island that has a widespread distribution in pathogenic and commensal human enterobacteria. Colibactin-producing gut microbes promote colon tumour formation and enhance the progression of colorectal cancer via cellular senescence and death induced by DNA double-strand breaks (DSBs); however, the chemical basis that contributes to the pathogenesis at the molecular level has not been fully characterized. Here, we report the discovery of colibactin-645, a macrocyclic colibactin metabolite that recapitulates the previously assumed genotoxicity and cytotoxicity. Colibactin-645 shows strong DNA DSB activity in vitro and in human cell cultures via a unique copper-mediated oxidative mechanism. We also delineate a complete biosynthetic model for colibactin-645, which highlights a unique fate of the aminomalonate-building monomer in forming the C-terminal 5-hydroxy-4-oxazolecarboxylic acid moiety through the activities of both the polyketide synthase ClbO and the amidase ClbL. This work thus provides a molecular basis for colibactin's DNA DSB activity and facilitates further mechanistic study of colibactin-related colorectal cancer incidence and prevention

EFFICACY OF ONE-ON-ONE PEER TUTORING IN IMPROVING THE PROBLEM-SOLVING PERFORMANCE AMONG THE GRADE 10 LEARNERS

This study aimed to determine the effectiveness of peer tutoring on the mathematical problem-solving performance of Grade 10 students in a public school in Cebu City during S.Y. 2021-2022. Utilizing a single-group pre-test and post-test research design, the study assessed the impact of peer tutoring on selected students' problem-solving performance in mathematics. Participants were chosen based on their math performance, and peer tutoring was conducted in a one-on-one tutor-tutee format. Two research tools were used: a Learner’s Questionnaire to gather students’ profiles and perceptions of the peer tutoring sessions and a Learners’ Achievement Test to measure their mathematical problem-solving performance. Both descriptive and inferential statistics were employed to analyze the data. Descriptive statistics, including weighted means and Likert scales, were used to summarize the students’ perceptions, while a z-test and paired t-test were used to compare pre-test and post-test scores. The results showed a significant improvement in the students' mathematical problem-solving abilities after the peer tutoring intervention, with a significant increase in their post-test scores. Furthermore, students perceived peer tutoring as highly beneficial in enhancing their understanding and ability to solve math problems. Based on these findings, it is recommended that educators utilize peer tutoring as an instructional strategy to improve students' mathematical problem-solving skills. This approach can also foster greater student participation and interest in learning mathematics.  Article visualizations

Proposta para a Implantação de Estruturas de uma Ponte Sobre o Rio Longá no Estado do Piauí – Brasil

A ideia de introduzir estados de esforço predeterminados com o fim de melhoraro comportamento de um elemento estrutural, é una excelente possibilidade deaplicação no concreto. Este material pode ter una elevada resistência a compressão, eem consequência a introdução de esforços prévios de compressão aplicados com a intençãode anular os de tração que apareceram durante a posta em serviço da estrutura,faz que o comportamento do concreto melhore substancialmente. Desta forma lograsepeças de tamanhos menores aos que obtêm-se em concreto armado, que ademãssão capazes de suportar cargas maiores e que presentão pouco o nenhuma rachadura oque melhora sua durabilidade. O trabalho consiste em apresentar uma proposta decálculo estrutural de uma ponte em concreto protendido sobre o rio Longá, que ficasituado no município de Campo Maior, no estado do Piauí – Brasil. O Local foi escolhidovisto às necessidades de moradores da região, na pequena Comunidade da Negra.Para o dimensionamento aborda-se a metodologia de cálculo das logarinas querecopilam as normas e os aspetos técnicos que tomam-se em conta, a funcionalidadepara o desenvolvimento de vigas protendidas, as equações básicas de dimensionamentosegundo o método LRFD e sus estados limites. Uma vez apresentados os cál -culos serão avaliados os resultados da análise estrutural aplicando o diagrama deMagnel e a manga de segurança

GÊNEROS E SEXUALIDADES NA ESCOLA: BREVES CONSIDERAÇÕES SOBRE OS PROCESSOS DE EXCLUSÃO NO COTIDIANO ESCOLAR E POLÍTICO BRASILEIRO

This article seeks to problematize the educational and political context in relation to sexual and gender diversity in schools today, seeking links between schooling processes and politicians in the maintenance of homophobia. It presents an analysis of the jobs of conservative groups that fight against inclusion and affirmative policies for the LGBTI + population in education, indicating the strategies and operationalization of precarious access and permanence in LGBTI + people schools. Moreover, the text presents a panorama of researchs and concetual discussions about homophobia in the school, at they reveals the processes of exclusions, victimizations, silencing and isolations in the context of school relations, seeking clues about ways of coping with this reality in school everyday and out of school. Recebido em: 19/05/ 2019Aprovado em: 23/09/2019O presente artigo busca problematizar o contexto educacional e político em relação a diversidade sexual e de gêneros na escolas na atualidade, buscando vinculações entre os processos de escolarização e os políticos na manutenção de homofobias. Apresenta uma análise das empreitas de grupos conservadores que lutam contra a inclusão e as políticas afirmativas para a população LGBTI + na educação, indicando as estratégias e operacionalização de precarização do acesso e permanência nas escolas de pessoas LGBTI+. Ainda, o texto apresenta um panorama de pesquisas sobre homofobia homofobia na escola que desvela os processos de produção de exclusões, vitimizações, silenciamentos e isolamentos no contexto das relações escolares, buscando pistas sobre modos de enfrentamento dessa realidade no cotidiano escolar e fora da escola. Recebido em: 19/05/ 2019Aprovado em: 23/09/201

Topochemical reduction of YMnO3 into a composite structure

Topochemical modification methods for solids have shown great potential in generating metastable structures inaccessible through classical synthetic routes. Here, we present the enhanced topotactic reduction of the multiferroic compound YMnO3. At moderate temperature in ammonia flow, the most reduced YMnO3-δ (δ = 0.5) phase could be stabilized. XRD, PND, and HREM results show that phase separation occurs into two intimately intergrown layered sublattices with nominal compositions ∞[YMn(2+)O2+x]((1-2x)+) and ∞[YMn(2+)O3-x]((1-2x)-) containing versatile Mn(2+) coordinations. The former sublattice shows original AA stacking between Mn layers, while AB stacking in the latter results from oxygen removal from the parent YMnO3 crystal structure

Proteasome Activity Influences UV-Mediated Subnuclear Localization Changes of NPM

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