O capital humano contempla o conjunto de habilidades, capacidades e conhecimentos de cada trabalhador, caracterizando-se como um importante elemento para fomentar a capacidade de inovação e a criação ...de vantagens competitivas sustentáveis, principalmente nas organizações intensivas em conhecimento, tais como as empresas que atuam na área de tecnologia da informação. Neste sentido, as corporações necessitam monitorar constantemente seus estoques reais de capital humano, avaliando, inclusive, a sua obsolescência. A partir destas perspectivas, o presente estudo objetiva caracterizar a obsolescência e os aspectos vinculados à aquisição do capital humano no contexto das empresas de tecnologia de informação. Para tanto, desenvolveu-se uma pesquisa de cunho qualitativo e quantitativo nas empresas vinculadas à Associação dos Provedores de Serviços e Informações da Internet (INTERNETSUL). Como principais resultados, identificou-se que os profissionais com formação em nível técnico e superior afirmam apresentar menores níveis de obsolescência do capital humano. Além disso, como formas predominantes de reduzir a depreciação de competências, destacaram-se o ensino superior e os cursos específicos na área. Por fim, em relação ao perfil dos profissionais, identificou-se que a autoaprendizagem é predominante em trabalhadores do gênero masculino, enquanto que profissionais com maiores níveis de escolaridade e tempo de experiência dispendem mais tempo para as atividades de aprendizagem no trabalho.
Plasmodium knowlesi is now established as the fifth Plasmodium species to cause malaria in humans. We describe a case of P. knowlesi infection acquired in Indonesian Borneo that was imported into ...Australia. Clinicians need to consider this diagnosis in a patient who has acquired malaria in forest areas of Southeast Asia.
In vivo somatostatin receptor scintigraphy using Octreoscan is a valuable method for the visualisation of human endocrine tumours and their metastases. Recently, several new, alternative somatostatin ...radioligands have been synthesised for diagnostic and radiotherapeutic use in vivo. Since human tumours are known to express various somatostatin receptor subtypes, it is mandatory to assess the receptor subtype affinity profile of such somatostatin radiotracers. Using cell lines transfected with somatostatin receptor subtypes sst1, sst2, sst3, sst4 and sst5, we have evaluated the in vitro binding characteristics of labelled (indium, yttrium, gallium) and unlabelled DOTA-Tyr3-octreotide, DOTA-octreotide, DOTA-lanreotide, DOTA-vapreotide, DTPA-Tyr3-octreotate and DOTA-Tyr3-octreotate. Small structural modifications, chelator substitution or metal replacement were shown to considerably affect the binding affinity. A marked improvement of sst2 affinity was found for Ga-DOTA-Tyr3-octreotide (IC50 2.5 nM) compared with the Y-labelled compound and Octreoscan. An excellent binding affinity for sst2 in the same range was also found for In-DTPA-Tyr3-octreotate (IC50 1.3 nM) and for Y-DOTA-Tyr3-octreotate (IC50 1.6 nM). Remarkably, Ga-DOTA-Tyr3-octreotate bound at sst2 with a considerably higher affinity (IC50 0.2 nM). An up to 30-fold improvement in sst3 affinity was observed for unlabelled or Y-labelled DOTA-octreotide compared with their Tyr3-containing analogue, suggesting that replacement of Tyr3 by Phe is crucial for high sst3 affinity. Substitution in the octreotide molecule of the DTPA by DOTA improved the sst3 binding affinity 14-fold. Whereas Y-DOTA-lanreotide had only low affinity for sst3 and sst4, it had the highest affinity for sst5 among the tested compounds (IC50 16 nM). Increased binding affinity for sst3 and sst5 was observed for DOTA-Tyr3-octreotide, DOTA-lanreotide and DOTA-vapreotide when they were labelled with yttrium. These marked changes in subtype affinity profiles are due not only to the different chemical structures but also to the different charges and hydrophilicity of these compounds. Interestingly, even the coordination geometry of the radiometal complex remote from the pharmacophoric amino acids has a significant influence on affinity profiles as shown with Y-DOTA versus Ga-DOTA in either Tyr3-octreotide or Tyr3-octreotate. Such changes in sst affinity profiles must be identified in newly designed radiotracers used for somatostatin receptor scintigraphy in order to correctly interpret in vivo scintigraphic data. These observations may represent basic principles relevant to the development of other peptide radioligands.
Abstract Cellulose nanocrystal (CNC)‐reinforced composites are gaining commercial attention on account of their high strength and sustainable sourcing. Grafting polymers to the CNCs in these ...composites has the potential to improve their properties, but current solution‐based synthesis methods limit their production at scale. Utilizing dynamic hindered urea chemistry, a new method for the melt‐functionalization of cellulose nanocrystals has been developed. This method does not require toxic solvents during the grafting step and can achieve grafting densities competitive with state‐of‐the‐art solution‐based grafting methods. Using cotton‐sourced, TEMPO‐oxidized CNCs, multiple molecular weights of poly(ethylene glycol) (PEG) as well as dodecane, polycaprolactone, and poly(butyl acrylate) were grafted to the CNC surface. With PEG‐grafted nanoparticles, grafting densities of 0.47 chains nm −2 and 0.10 chains nm −2 were achieved with 2000 and 10,000 g mol −1 polymer chains respectively, both of which represent significant improvements over previous reports for solution‐based PEG grafting onto CNCs.
Evidence indicates that domestic violence has negative consequences on victims’ employment; yet employers lag in recognizing this as a workplace issue. To address the problem, some states have ...established several policy solutions. To understand the scope of the public sector’s response to domestic violence as a workplace issue, a content analysis of state-level employment protection policies for domestic violence victims (N = 369) was conducted. Results indicate three broad policy categories: (a) policies that offer work leave for victims; (b) policies that aim to reduce employment discrimination of domestic violence victims; and (c) policies that aim to increase awareness and safety in the workplace. Subcategories emerged within each of these three categories. Implementation of employment protection policies varies significantly across states. Implications for workplaces, practitioners, and policy leaders are discussed.
Reconstructing stimuli from the spike trains of neurons is an important approach for understanding the neural code. One of the difficulties associated with this task is that signals which are varying ...continuously in time are encoded into sequences of discrete events or spikes. An important problem is to determine how much information about the continuously varying stimulus can be extracted from the time-points at which spikes were observed, especially if these time-points are subject to some sort of randomness. For the special case of spike trains generated by leaky integrate and fire neurons, noise can be introduced by allowing variations in the threshold every time a spike is released. A simple decoding algorithm previously derived for the noiseless case can be extended to the stochastic case, but turns out to be biased. Here, we review a solution to this problem, by presenting a simple yet efficient algorithm which greatly reduces the bias, and therefore leads to better decoding performance in the stochastic case.
The Carmel coast is a hotspot for Bronze Age stone anchors, a common find along the whole Israeli coastline. Besides ceramics, stone anchors are some of the most common artifacts found during ...underwater excavations and surveys. The overall aim of this thesis is to identify the origins of stone anchors found in well-dated underwater assemblages to infer past maritime connections. Specifically, the thesis focuses on Middle and Late Bronze Age stone anchors of the Byblian and Uluburun types. Previous research found that most stone anchors of these types were made from carbonate rocks or aeolianites, rock types that are common in the Eastern Mediterranean region and cannot be easily distinguished into quarry sites on a micro-regional scale. This difficulty hampers their provenance identification, and therefore the thesis focused on developing a method for provenancing stone anchors made of carbonate rocks and aeolianites by characterizing their chemical, isotopic, and mineralogical compositions, as well as studying their petrographic characteristics. To achieve this study's goal, I compiled a reference collection of carbonate rocks from each geological formation that is easily accessible from the coast of Israel (less than 3 km distance from the coastline), focusing on the Northern and Carmel coastal regions. The characteristics of the reference rocks were then compared to those of archaeological stone anchors from four sites with welldated underwater assemblages found off the Carmel coast: (1) Neve Yam - one of the largest groups of Middle Bronze (MB) Byblian type anchors underwater part of a shipwreck assemblage, and a large Late Bronze (LB) Uluburun type anchor with associated copper ingots, (2) Atlit – individual BA Byblian type anchor in the North Bay, (3) Kfar Samir – two LB Uluburun type anchor assemblages, one associated with a metal cargo and an Egyptian sickle sword, and (4) Hishuley Carmel – LB Uluburun type anchors associated with a metal cargo including tin, lead, and copper ingots, and metal tools. The results of the analyses conducted on the reference samples characterized 11 geological formations composed of limestone, chalk, and dolomite, 15 samples of aeolianites and 6 samples of beachrock. Prior to laboratory analyses, the rocks were immersed in water to examine their interaction with this substance, a parameter important for the manufacture of anchors. Characterization of the rock references included elemental analysis through ICP-MS and ICP-AES, mineralogy through Fourier Transform Infrared (FTIR) spectroscopy of bulk rock and its acid insoluble fraction, FTIR grinding curves, stable isotopes of carbon and oxygen of bulk rock samples, and petrographic microscopy. This set of techniques was designed to follow a series of steps so that the stone anchors and reference samples were analyzed following the same procedure. I found that certain rock formations, those including relatively high amounts of clay, disintegrated in water immersion and are therefore unsuitable and unlikely to have been used as sources for archaeological anchors. I found that the majority of the carbonate rock stone anchors originate from two local formations: Arqan and Isfiye. These are chalk formations that apparently possess certain material qualities that make them suitable for carving (unlike dolomites, for example, that can potentially serve for anchor preparation, but according to this study were not used as anchors).
Data science is an iterative, exploratory, and ad-hoc process performed by individuals and teams possessing increasingly varied backgrounds and skill-sets. As such, we need data science to be ...interactive, so that data scientists are not bottlenecked when trying out new hypotheses or confirming existing ones. Moreover, data science must be safe, ensuring that data scientists, especially those with limited programming or analysis experience, avoid making incorrect inferences. Safety and interactivity are typically at odds with one another, since various notions of safety often eschew “shortcuts” that make working with large-scale data tractable. In this dissertation, we aim to meet the dual objectives of interactivity and safety at scale by leveraging distributional context—specifically the distributions of the data and the operations performed by data scientists.We apply this “recipe” to five different key data science settings: (i) for machine learning development, we provide context-aware caching algorithms that allow model developers to benefit from interactive iteration times during model development, while not requiring error-prone manual tracking of reusable intermediates; (ii) for visualization search, we develop context-aware sampling algorithms that support interactive search for patterns in visualizations, while ensuring that the results meet rigorous quality guarantees; (iii) for browsing, we develop workload-aware learned Bloom filters optimized for multidimensional data that allow analysts to quickly identify records that have been examined before, all while guarding against false negatives; (iv) for report generation, we develop context-aware aggregate approximation algorithms that provide rigorous distribution-aware confidence intervals around aggregates, while ensuring that the intervals are “tighter”, allowing analysts to make decisions sooner; and (v) finally, for error-prone interactions in computational notebooks, we demonstrate approximate lineage-capture techniques that warn data scientists of unsafe cell executions for many cases encountered in practice.
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