Results 31 to 40 of about 3,770,727 (360)

Clusters espaciais de “agriculturalização” no meio rural de alguns estados brasileiros

Revista de Economia e Sociologia Rural, 2020
Resumo: O meio rural brasileiro tem se caracterizado, em especial nas últimas quatro décadas, pela diminuição da sua população, diminuição do total de pessoas ocupadas na agropecuária e pelo crescimento de atividades não agrícolas.
Alysson Luiz Stege, Carlos José Caetano Bacha   +1 more
doaj   +1 more source

Clustering‐Induced White Light Emission from Carbonized Polymer Dots

Advanced Photonics Research, 2021
Despite the advancements in synthetic methods, it is still challenging to prepare white light‐emitting carbon dots for solid‐state white light‐emitting diodes (LEDs). Herein, the synthesis and characterization of a carbonized polymer dot (CPD) that emits
Bin Liu, Zheng Chen, Bo Chu, Ya-Ling Wang, Ning Li, Huinian Zhang, Yongzhen Yang, Shengliang Hu, Xing-Hong Zhang   +8 more
doaj   +1 more source

Wake-Up Receiver-Based Routing for Clustered Multihop Wireless Sensor Networks

Sensors, 2022
The Wireless Sensor Network (WSN) is one of the most promising solutions for the supervision of multiple phenomena and for the digitisation of the Internet of Things (IoT).
Maximilian Weber, Ghofrane Fersi, Robert Fromm, Faouzi Derbel   +3 more
doaj   +1 more source

NbClust: An R Package for Determining the Relevant Number of Clusters in a Data Set

, 2014
Clustering is the partitioning of a set of objects into groups (clusters) so that objects within a group are more similar to each others than objects in different groups. Most of the clustering algorithms depend on some assumptions in order to define the
Malika Charrad, Nadia Ghazzali, V. Boiteau, A. Niknafs   +3 more
semanticscholar   +1 more source

Community Structure in Large Networks: Natural Cluster Sizes and the Absence of Large Well-Defined Clusters [PDF]

Internet Mathematics, 2008
A large body of work has been devoted to defining and identifying clusters or communities in social and information networks, i.e., in graphs in which the nodes represent underlying social entities and the edges represent some sort of interaction between
J. Leskovec, Kevin J. Lang, Anirban Dasgupta, Michael W. Mahoney   +3 more
semanticscholar   +1 more source

Young, Massive Star Clusters in the Antennae [PDF]

, 2008
While massive star clusters have been detected in almost every galaxy with appreciable star formation, they are most prevalent in interacting and merging galaxies. As many as 95% of these clusters will ultimately be disrupted, often in the first 10 Myr,
Christopher, Micol Huw
core   +1 more source

Diabetes mellitus and the risk of spontaneous bacterial peritonitis in patients with liver cirrhosis: a systematic review and meta-analysis

Annals of Saudi Medicine
BACKGROUND: Spontaneous bacterial peritonitis (SBP) represents a critical and potentially lethal condition that typically develops in individuals with liver cirrhosis.
Raghad Alhajaji, Mayada Mohammad Samkari, Mona A. Althobaiti, Bashaer Ruddah Al-Ahmadi, Alaa Mohammed Bugis, Amjad Mohammed Bugis, Fatimah Yaseen Sabbagh, Somaya A. Althobaiti, Amro S. Bukari, Safenaz Meshal Alqurashi, Hana Abdullah Mshrai, Omar Ahmed Abdelwahab   +11 more
doaj   +1 more source

Mediating Effects of the COVID-19 Pandemic on the Associations between Physical Activity and Physical Fitness; Cross-Sectional Study among High School Adolescents

Journal of Functional Morphology and Kinesiology, 2023
The COVID-19 pandemic and the imposed social distancing measures caused negative changes in physical activity levels (PALs) and physical fitness (PF) among adolescents, but the potential mediating effect of the pandemic on the association between PAL and
Mirela Sunda, Barbara Gilic, Petra Rajkovic Vuletic, Vladimir Pavlinovic, Natasa Zenic   +4 more
doaj   +1 more source

Design and Construction of Novel Frustrated Lewis Pairs Based on Modified Lewis Acid B(C₆F₅)₃

Crystals
This study aims to systematically investigate the influence of substituent effects on the strength of Lewis acid–base interactions in frustrated Lewis pairs (FLPs). Specifically, -C6F5 groups of the classical Lewis acid B(C6F5)3 are sequentially replaced
Quanwei Wang, Zonggui Li, Yanuo Cui, Jiashuo Zhang, Huilin Li, Wei Li   +5 more
doaj   +1 more source

Hyper-Cross-Linked Polystyrene as a Stabilizing Medium for Small Metal Clusters

Molecules, 2021
Among different polymers nanostructured cross-linked aromatics have the greatest potential as catalytic supports due to their exceptional thermal and chemical stability and preservation of the active phase morphology.
Alexey V. Bykov, Galina N. Demidenko, Linda Zh. Nikoshvili, Lioubov Kiwi-Minsker   +3 more
doaj   +1 more source