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1.
Sci Adv ; 10(26): eadp2887, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941472

RESUMO

Eyed needles are among the most iconic of Paleolithic artifacts, traditionally seen as rare indicators of prehistoric clothing, particularly tailoring. However, recent finds across Africa and Eurasia show that other technologies like bone awls also facilitated the creation of fitted garments. Nonetheless, the advent of delicate eyed needles suggests a demand for more refined, efficient sewing. This refinement may signify two major developments: the emergence of underwear in layered garment assemblages, and/or a transition in adornment from body modification to decorating clothes, as humans covered themselves more completely for thermal protection. Archaeological evidence for underwear is limited, but the Upper Paleolithic saw an increase in personal ornaments, some sewn onto clothing. Eyed needles may mark a pivotal shift as clothes acquired the social functions of dress, decoupling clothing from climate and ensuring its enduring presence.


Assuntos
Arqueologia , Vestuário , Humanos , Vestuário/história , História Antiga
2.
Nat Hum Behav ; 8(3): 431-444, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38287173

RESUMO

Mechanisms governing the relationship between genetic and cultural evolution are the subject of debate, data analysis and modelling efforts. Here we present a new georeferenced dataset of personal ornaments worn by European hunter-gatherers during the so-called Gravettian technocomplex (34,000-24,000 years ago), analyse it with multivariate and geospatial statistics, model the impact of distance on cultural diversity and contrast the outcome of our analyses with up-to-date palaeogenetic data. We demonstrate that Gravettian ornament variability cannot be explained solely by isolation-by-distance. Analysis of Gravettian ornaments identified nine geographically discrete cultural entities across Europe. While broadly in agreement with palaeogenetic data, our results highlight a more complex pattern, with cultural entities located in areas not yet sampled by palaeogenetics and distinctive entities in regions inhabited by populations of similar genetic ancestry. Integrating personal ornament and biological data from other Palaeolithic cultures will elucidate the complex narrative of population dynamics of Upper Palaeolithic Europe.


Assuntos
Evolução Cultural , Humanos , Europa (Continente) , Dinâmica Populacional , Diversidade Cultural
3.
Nat Ecol Evol ; 8(3): 552-563, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38238436

RESUMO

The geographic expansion of Homo sapiens populations into southeastern Europe occurred by ∼47,000 years ago (∼47 ka), marked by Initial Upper Palaeolithic (IUP) technology. H. sapiens was present in western Siberia by ∼45 ka, and IUP industries indicate early entries by ∼50 ka in the Russian Altai and 46-45 ka in northern Mongolia. H. sapiens was in northeastern Asia by ∼40 ka, with a single IUP site in China dating to 43-41 ka. Here we describe an IUP assemblage from Shiyu in northern China, dating to ∼45 ka. Shiyu contains a stone tool assemblage produced by Levallois and Volumetric Blade Reduction methods, the long-distance transfer of obsidian from sources in China and the Russian Far East (800-1,000 km away), increased hunting skills denoted by the selective culling of adult equids and the recovery of tanged and hafted projectile points with evidence of impact fractures, and the presence of a worked bone tool and a shaped graphite disc. Shiyu exhibits a set of advanced cultural behaviours, and together with the recovery of a now-lost human cranial bone, the record supports an expansion of H. sapiens into eastern Asia by about 45 ka.


Assuntos
Fósseis , Crânio , Humanos , China , Europa (Continente) , Antropologia Cultural
4.
Chemistry ; 30(12): e202303771, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38118132

RESUMO

This work explores the potential of carbon dots as a fluorescent probe in the determination of heavy ions and as an electrochemical biosensor. It also discusses how carbon dots can be introduced into the Fricke solution to potentially serve as an ionizing radiation sensor. The study presents a novel tissue equivalent dosimeter carbon dots-based as an ionizing radiation sensor. The methodology for the synthesis of Nitrogen-doped Carbon Dots N-CDs and the characterization of the material are described. The results show that the N-CDs have a high sensitivity to ionizing radiation and can be used as a dosimeter for radiation detection. The study also discusses the limitations and challenges of using carbon dots as a dosimeter for ionizing radiation. Overall, this study provides valuable insights into the potential applications of carbon dots in different fields and highlights the importance of further research in this area.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Pontos Quânticos/química , Carbono/química , Dosímetros de Radiação , Nitrogênio/química , Corantes Fluorescentes/química
5.
PLoS One ; 18(11): e0291552, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37910580

RESUMO

Upper Palaeolithic sites in southwestern France attributed to the Upper Gravettian and the Solutrean yielded sub spherical gravels with a highly shiny appearance that have intrigued researchers since the 1930s. In this work, we analyze specimens from five sites, including the recently excavated Solutrean site of Landry, to establish whether their presence in archaeological layers and peculiar aspect are due to natural processes or human agency. We study the spatial distribution of gravels at Landry and submit archaeological gravels from the five sites, natural formations, Landry sediment sieving, and polishing experiments with a rotary tumbling machine to morphometric, colorimetric, microscopic, and textural analyses. Our results indicate the lustrous gravels found at the five sites result from deliberate selection and suggest their shiny appearance is the consequence of human agency, possibly resulting from prolonged contact with a soft material such as animal skin. Ethnographic accounts indicate that these gravels may have been used for magico-religious ritual purposes (charms, sorcery, divination etc.), in games, as elements of musical instruments, and as items serving other social and personal purposes. We argue that these objects reflect a cultural innovation emerged during the Gravettian and continued into the Solutrean.


Assuntos
Arqueologia , Animais , Humanos , França
6.
Sci Rep ; 13(1): 13261, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37684298

RESUMO

The use of mineral pigments, in particular iron-rich rocks, holds significant importance in understanding the emergence and evolution of human cultures. However, sites that have yielded a number of pieces large enough to precisely identify how the use of this material changed through time are rare. In this study, we examine one of the largest known Middle Stone Age (MSA) ochre collections, from Porc-Epic Cave, Ethiopia, consisting of more than 40 kg of ochre (n = 4213 pieces), 21 ochre processing tools and two ochre-stained artefacts. By combining the analysis of the elemental and mineralogical composition of the archaeological material with that of natural ochre collected in the surroundings of the site, and correlating this information with shifts in ochre modification techniques over time, we unveil how MSA inhabitants of Porc-Epic Cave exploited mineral resources. We show that they could predict the properties of different ochre types accessible in their environment, and gradually adapted their technology to cope with changes in raw material availability. Furthermore, the analysis of ochre residues on a painted pebble, likely used to produce red dots on a surface, identifies an ochre type that was specifically employed for symbolic purposes.


Assuntos
Arqueologia , Artefatos , Humanos , Etiópia , Cavernas
7.
J Hum Evol ; 184: 103438, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37742522

RESUMO

The emergence of technologies to culturally modify the appearance of the human body is a debated issue, with earliest evidence consisting of perforated marine shells dated between 140 and 60 ka at archaeological sites from Africa and western Asia. In this study, we submit unpublished marine and estuarine gastropods from Blombos Cave Middle Stone Age layers to taxonomic, taphonomic, technological, and use-wear analyses. We show that unperforated and naturally perforated eye-catching shells belonging to the species Semicassis zeylanica, Conus tinianus, and another Conus species, possibly Conus algoensis, were brought to the cave between 100 and 73 ka. At ca. 70 ka, a previously unrecorded marine gastropod, belonging to the species Tritia ovulata, was perforated by pecking and was worn as an ornamental object, isolated or in association with numerous intentionally perforated shells of the species Nassarius kraussianus. Fluctuations in sea level and consequent variations in the site-to-shoreline distances and landscape modifications during the Middle Stone Age have affected the availability of marine shells involved in symbolic practices. During the M3 and M2 Lower phases, with a sea level 50 m lower, the site was approximately 3.5 km away from the coast. In the later M2 Upper and M1 phases, with a sea level at -60 m, the distance increased to about 5.7 km. By the end of the M1 phase, when the site was abandoned, Blombos Cave was situated 18-30 km from the shoreline. We use the new Blombos evidence and a review of the latest findings from Africa and Eurasia to propose a testable ten-step evolutionary scenario for the culturalization of the human body with roots in the deep past.

8.
Radiat Prot Dosimetry ; 199(14): 1591-1599, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37721086

RESUMO

This work presents the computational analysis of the sensitivity improvements that could be achieved in lithium formate monohydrate (LFM) electron paramagnetic resonance (EPR) dosemeters exposed to neutron beams. Monte Carlo (MC) simulations were performed on LFM pellets exposed to neutron beams with different energy spectra at various depths inside a water phantom. Various computations were carried out by considering different enrichments of 6Li inside the LFM matrix as well as addition of different amounts of gadolinium oxide inside the pellet blend. The energy released per unit mass was calculated with the aim of predicting the increase in dose achievable by the addition of sensitizers inside the pellets. As expected, a larger amount of 6Li induces an increase of energy released because of the charged secondary particles (i.e. 3H ions and α-particles) produced after neutron capture. For small depths in water phantom and low-energy neutron spectra the dose increase due to 6Li enrichment is high (more than three orders of magnitude with respect to the case of with 7Li). In case of epithermal neutron beams the energy released in 6Li-enriched LFM compound is smaller but larger than in the case of fast neutron beams. On the other hand, the computational analysis evidenced that gadolinium is less effective than 6Li in improving neutron sensitivity of the LFM pellets. Discussion based on the features of MC transport code is provided. This result suggests that 6Li enrichment of LFM dosemeters would be more effective for neutron sensitivity improvement and these EPR dosemeters could be tested for dosimetric applications in Neutron Capture Therapy.


Assuntos
Nêutrons Rápidos , Nêutrons , Espectroscopia de Ressonância de Spin Eletrônica , Água
9.
Sci Rep ; 13(1): 12895, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37558802

RESUMO

The earliest European carvings, made of mammoth ivory, depict animals, humans, and anthropomorphs. They are found at Early Aurignacian sites of the Swabian Jura in Germany. Despite the wide geographical spread of the Aurignacian across Europe, these carvings have no contemporaneous counterparts. Here, we document a small, intriguing object, that sheds light on this uniqueness. Found at the Grotte des Gorges (Jura, France), in a layer sandwiched between Aurignacian contexts and dated to c. 36.2 ka, the object bears traces of anthropogenic modifications indicating intentional carving. Microtomographic, microscopic, three-dimensional roughness and residues analyses reveal the carving is a fragment of a large ammonite, which was modified to represent a caniformia head decorated with notches and probably transported for long time in a container stained with ochre. While achieving Swabian Jura-like miniaturization, the Grotte des Gorges specimen displays original features, indicating the craftsman emulated ivory carvings while introducing significant technical, thematic, and stylistic innovations. This finding suggests a low degree of cultural connectivity between Early Aurignacian hunter-gatherer groups in the production of their symbolic material culture. The pattern conforms to the existence of cultural boundaries limiting the transmission of symbolic practices while leaving space for the emergence of original regional expressions.


Assuntos
Arqueologia , Hominidae , Humanos , Animais , Arqueologia/métodos , Europa (Continente) , França , Cavernas
10.
Sci Adv ; 9(15): eadg0834, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37043572

RESUMO

Puncture alignments are found on Palaeolithic carvings, pendants, and other fully shaped osseous artifacts. These marks were interpreted as abstract decorations, system of notations, and features present on human and animal depictions. Here, we create an experimental framework for the analysis and interpretation of human-made punctures and apply it to a highly intriguing, punctured bone fragment found at Canyars, an Early Upper Palaeolithic coastal site from Catalonia, Spain. Changes of tool and variation in the arrangement and orientation of punctures are consistent with the interpretation of this object as the earliest-known leather work punch board recording six episodes of hide pricking, one of which was to produce a linear seam. Our results indicate that Aurignacian hunters-gatherers used this technology to produce leather works and probably tailored clothes well before the introduction of bone eyed needles in Europe 15,000 years later.

11.
J Environ Radioact ; 259-260: 107109, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36652762

RESUMO

Analysis of cytogenetics effects of ionizing radiation for flora and fauna is essential to determine the impact on these communities and may produce an efficient warning system to avoid harm to human health. Onion (Allium cepa) is a well-established in vivo standard model, and it is widely used in cytogenetics studies for different environmental pollutants. In this work, onion roots were exposed to 0.04-1.44 Gy of ß-particles from a 90Sr/90Y source. We investigated the capacity of brief external exposures to ß-particles on inducing cytogenetic damages in root meristematic cells of onion aiming to verify if onion can be used as a radiation-sensitive cytogenetic bioindicator. A nonlinear increase in the frequencies of chromosomal aberrations and cells with micronuclei was observed. Onion roots exposed to doses 0.13 Gy or higher of ß-particles showed a significant difference (p<0.05) in these frequencies when compared to the unirradiated group. The frequencies of these endpoints showed to be suitable to assess the difference in the dose of beta radiation received from 0.36 Gy. Our research shows the potential of using cytogenetic effects in Allium cepa cells as a biological indicator for a first screening of genotoxic damages induced by brief external exposures to ß-particles.


Assuntos
Allium , Monitoramento de Radiação , Humanos , Cebolas/genética , Cebolas/efeitos da radiação , Biomarcadores Ambientais , Partículas beta , Raízes de Plantas , Aberrações Cromossômicas , Análise Citogenética , Dano ao DNA
12.
Sci Rep ; 12(1): 16270, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175454

RESUMO

Fully shaped, morphologically standardized bone tools are generally considered reliable indicators of the emergence of modern behavior. We report the discovery of 23 double-beveled bone tools from ~ 80,000-60,000-year-old archaeological layers at Sibudu Cave in KwaZulu-Natal, South Africa. We analyzed the texture of use-wear on the archaeological bone tools, and on bone tool replicas experimentally used in debarking trees, processing rabbit pelts with and without an ochre compound, digging in sediment in and outside a cave, and on ethnographic artefacts. Debarking trees and digging in humus-rich soil produce use-wear patterns closely matching those observed on most Sibudu tools. This tool type is associated with three different Middle Stone Age cultural traditions at Sibudu that span 20,000 years, yet they are absent at contemporaneous sites. Our results support a scenario in which some southern African early modern human groups developed and locally maintained specific, highly standardized cultural traits while sharing others at a sub-continental scale. We demonstrate that technological and texture analyses are effective means by which to infer past behaviors and assess the significance of prehistoric cultural innovations.


Assuntos
Arqueologia , Tecnologia , Animais , Antropologia Cultural , Humanos , Recém-Nascido , Coelhos , Solo , África do Sul , Árvores
13.
PLoS One ; 17(8): e0271732, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35921273

RESUMO

It has been suggested that engraved abstract patterns dating from the Middle and Lower Palaeolithic served as means of representation and communication. Identifying the brain regions involved in visual processing of these engravings can provide insights into their function. In this study, brain activity was measured during perception of the earliest known Palaeolithic engraved patterns and compared to natural patterns mimicking human-made engravings. Participants were asked to categorise marks as being intentionally made by humans or due to natural processes (e.g. erosion, root etching). To simulate the putative familiarity of our ancestors with the marks, the responses of expert archaeologists and control participants were compared, allowing characterisation of the effect of previous knowledge on both behaviour and brain activity in perception of the marks. Besides a set of regions common to both groups and involved in visual analysis and decision-making, the experts exhibited greater activity in the inferior part of the lateral occipital cortex, ventral occipitotemporal cortex, and medial thalamic regions. These results are consistent with those reported in visual expertise studies, and confirm the importance of the integrative visual areas in the perception of the earliest abstract engravings. The attribution of a natural rather than human origin to the marks elicited greater activity in the salience network in both groups, reflecting the uncertainty and ambiguity in the perception of, and decision-making for, natural patterns. The activation of the salience network might also be related to the process at work in the attribution of an intention to the marks. The primary visual area was not specifically involved in the visual processing of engravings, which argued against its central role in the emergence of engraving production.


Assuntos
Gravuras e Gravação , Lobo Occipital , Arqueologia , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética/métodos , Lobo Occipital/fisiologia , Reconhecimento Psicológico
14.
Radiat Prot Dosimetry ; 198(16): 1230-1237, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-35863068

RESUMO

The detailed dose analysis at the extremities remains a challenge, without affecting operators' mobility and their tactile sense. Using films loaded with optically stimulated luminescence (OSL) crystals have been studied in order to overcome some of these challenges in 2D dosimetry. In this work, we investigated flexible polymeric films loaded with MgB4O7:Ce,Li to acquire a better understanding of the dependence of the dosimetric signal characteristics on the production process and the influence of using different powder grain sizes. In film production, five different solvents were used: acetone-benzene, dichloromethane, chloroform, tetrahydrofuran and formic acid. Our results indicate that acetone-benzene is the solvent mixture that less influences the signal emitted by treated crystals, in comparison with the signal emitted by the pristine crystal powder. Conversely, by using formic acid, the crystalline structure of the sample was most severely modified, leading to a drastic reduction of the emitted OSL signal. We found that the extent of the grain surface in contact with the solvent in the process is important and should be taken into consideration when choosing the proper grain size to be used. Highlights  Polymeric films loaded with MgB4O7:Ce,Li crystals were produced using different solvents.Different effect on the OSL signal was found depending on the used solvent.Among the evaluated solvents, acetone-benzene was the one that less affected the OSL signal.


Assuntos
Dosimetria por Luminescência Estimulada Opticamente , Acetona , Benzeno , Clorofórmio , Formiatos , Furanos , Luminescência , Cloreto de Metileno , Dosimetria por Luminescência Estimulada Opticamente/métodos , Polímeros , Pós , Solventes
15.
Nature ; 603(7900): 284-289, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236981

RESUMO

Homo sapiens was present in northern Asia by around 40,000 years ago, having replaced archaic populations across Eurasia after episodes of earlier population expansions and interbreeding1-4. Cultural adaptations of the last Neanderthals, the Denisovans and the incoming populations of H. sapiens into Asia remain unknown1,5-7. Here we describe Xiamabei, a well-preserved, approximately 40,000-year-old archaeological site in northern China, which includes the earliest known ochre-processing feature in east Asia, a distinctive miniaturized lithic assemblage with bladelet-like tools bearing traces of hafting, and a bone tool. The cultural assembly of traits at Xiamabei is unique for Eastern Asia and does not correspond with those found at other archaeological site assemblages inhabited by archaic populations or those generally associated with the expansion of H. sapiens, such as the Initial Upper Palaeolithic8-10. The record of northern Asia supports a process of technological innovations and cultural diversification emerging in a period of hominin hybridization and admixture2,3,6,11.


Assuntos
Arqueologia , Hominidae , Comportamento de Utilização de Ferramentas , Animais , Osso e Ossos , China , História Antiga , Humanos , Homem de Neandertal
16.
Sensors (Basel) ; 22(3)2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35161824

RESUMO

Since the Fukushima Daiichi Nuclear Power Plant accident in March 2011, the technology available for unmanned aerial vehicles (UAVs) for radiation monitoring has improved greatly. Remote access to radiation-contaminated areas not only eliminates unnecessary exposure of civilians or military personnel, but also allows workers to explore inaccessible places. Hazardous levels of radioactive contamination can be expected as a result of accidents in the nuclear power industry or as a result of the intentional release of radioactive materials for terrorist purposes (dirty bombs, building contamination, etc.). The possibility to detect, identify, and characterize radiation and nuclear material using mobile and remote sensing platforms is a common requirement in the radiation sensing community. The technology has applications in homeland security and law enforcement, customs and border protection, nuclear power plant safety and security, nuclear waste monitoring, environmental recovery, and the military. In this work, the authors have developed, implemented, and characterized a gamma-ray detection and spectroscopy system capable of operating on a UAV. The system was mainly developed using open-source software and affordable hardware components to reduce development and maintenance costs and provide satisfactory performance as a detection instrument. The designed platform can be used to perform mapping or localization tasks to improve the risk assessment process for first responders during the management of radiological and nuclear incidents. First, the design process of the system is described; the result of the characterization of the platform is then presented together with the use of the prototype installed on a UAV in an exercise simulating a radiological and nuclear contamination scenario.


Assuntos
Monitoramento de Radiação , Terrorismo , Humanos , Centrais Nucleares
17.
Plants (Basel) ; 11(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35050110

RESUMO

The aim of this work is to analyze the effects of ionizing radiation and radionuclides (like 137Cs) in several higher plants located around the Fukushima Dai-ichi Nuclear Power Plant (FNPP), evaluating both their adaptive processes and evolution. After the FNPP accident in March 2011 much attention was focused to the biological consequences of ionizing radiation and radionuclides released in the area surrounding the nuclear plant. This unexpected mishap led to the emission of radionuclides in aerosol and gaseous forms from the power plant, which contaminated a large area, including wild forest, cities, farmlands, mountains, and the sea, causing serious problems. Large quantities of 131I, 137Cs, and 134Cs were detected in the fallout. People were evacuated but the flora continued to be affected by the radiation exposure and by the radioactive dusts' fallout. The response of biota to FNPP irradiation was a complex interaction among radiation dose, dose rate, temporal and spatial variation, varying radiation sensitivities of the different plants' species, and indirect effects from other events. The repeated ionizing radiations, acute or chronic, guarantee an adaptation of the plant species, demonstrating a radio-resistance. Consequently, ionizing radiation affects the genetic structure, especially during chronic irradiation, reducing genetic variability. This reduction is associated with the different susceptibility of plant species to chronic stress. This would confirm the adaptive theory associated with this phenomenon. The effects that ionizing radiation has on different life forms are examined in this review using the FNPP disaster as a case study focusing the attention ten years after the accident.

18.
PLoS One ; 17(1): e0262143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35073338

RESUMO

Paint technology, namely paint preparation and application procedures, is an important aspect of painting traditions. With the expansion of archaeometric studies and in situ non-destructive analytical methods, a renewal of technological studies is being observed in rock art. In situ analyses have several limitations that are widely discussed in the literature, however. It is not yet clear whether they provide accurate information on paint technology, except under certain conditions. Here, we evaluated digital microscopic and pXRF in situ analyses for the characterisation of a large set of red and yellow paintings from the El Castillo cave, Cantabria, Spain. We have set experiments and used statistical methods to identify differences between paint components and determine factors impacting pXRF measurements. We found that the compositional heterogeneity of the paintings' environment, especially variations in secondary deposits, was responsible for most of the differences observed between the pXRF signals recorded on the paintings. We concluded that the El Castillo cave environment is not suitable for non-destructive technological studies, but that more favourable contexts might exist. Following previous works and our own results, we advocate a combination of both in situ and laboratory invasive analyses for the study of paint composition and paint technology. Our research protocol, based on the comparison of rock paintings, their substrate, experimental paintings and Fe-normalisation of the signals can improve the reliability of pXRF results. We also propose to include more systematic characterisation of rock wall heterogeneity and the use of microscopic analyses in non-destructive approaches.


Assuntos
Corantes/análise , Pintura/análise , Cavernas , Microscopia , Pinturas , Espanha , Espectrometria por Raios X
19.
Eur Phys J Plus ; 137(1): 37, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34956809

RESUMO

Ultraviolet germicidal irradiation (UVGI) uses short-wave ultraviolet (UVC) light to inactivate organisms like viruses, bacteria, and fungi. UVC inactivates a wide range of microorganisms by damaging the structure of nucleic acids and proteins at the molecular level, so they become unable to replicate and cause disease. Thus, UVC can improve indoor air quality by controlling bioaerosols and can be used as an engineering device to interrupt the transmission of pathogenic organisms and potential bioterrorism agents. Recently, the World Health Organization recognized that the COVID-19 virus could be transmitted across large distances, suggesting that indoor ventilation is key in airborne transmission. As a test for the future dissemination of UVC light installations to improve indoor air quality in Hospitals in Sergipe State, Brazil, we made a first installation of UVGI disinfection lamps, strategically placed in the Heating, Ventilating, and Air Conditioning (HVAC) system of the Intensive Care Unit (ICU) at the University Hospital of Lagarto, Federal University of Sergipe, Brazil. Six 15 W low-vapor-pressure mercury lamps emitting 253.7 nm UVGI were installed in the ducts of the fan coil, maximizing their luminous interaction in the air passage. One of the greatest advantages of this type of installation is that the lamps were completely covered, avoiding any risk of hazardous exposure to people and animals. Microbiological tests were carried out to verify the germicidal effect, analyzing the viability of microorganisms circulating in the environment. In this paper, we present our encouraging results, demonstrating the effectiveness of the installation, suggesting that similar devices should be installed in HVAC systems to avoid biological risk to people inside buildings. In addition, we believe that this study may provide useful evidence and guidance for the design of equipment intended to abate the microorganisms that may be used in CBRNE terror attacks.

20.
Behav Brain Sci ; 44: e199, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34907875

RESUMO

Clarke and Beck's defense of the theoretical construct "approximate number system" (ANS) is flawed in serious ways - from biological misconceptions to mathematical naïveté. The authors misunderstand behavioral/psychological technical concepts, such as numerosity and quantical cognition, which they disdain as "exotic." Additionally, their characterization of rational numbers is blind to the essential role of symbolic reference in the emergence of number.


Assuntos
Cognição , Idioma , Humanos , Matemática , Percepção
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