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1.
Chem Pharm Bull (Tokyo) ; 72(7): 664-668, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38987174

RESUMEN

Henna is a plant-based dye obtained from the powdered leaf of the pigmented plant Lawsonia inermis, and has often been used for grey hair dyeing, treatment, and body painting. As a henna product, the leaves of Indigofera tinctoria and Cassia auriculata can be blended to produce different colour variations. Although allergy from henna products attributed to p-phenylenediamine, which is added to enhance the dye, is reported occasionally, raw material plants of henna products could also contribute to the allergy. In this study, we reported that raw material plants of commercial henna products distributed in Japan can be estimated by LC-high resolution MS (LC-HRMS) and multivariate analysis. Principal Component Analysis (PCA) score plot clearly separated 17 samples into three groups [I; henna, II; blended henna primarily comprising Indigofera tinctoria, III; Cassia auriculata]. This grouping was consistent with the ingredient lists of products except that one sample listed as henna was classified as Group III, indicating that its ingredient label may differ from the actual formulation. The ingredients characteristic to Groups I, II, and III by PCA were lawsone (1), indirubin (2), and rutin (3), respectively, which were reported to be contained in each plant as ingredients. Therefore, henna products can be considered to have been manufactured from these plants. This study is the first to estimate raw material plants used in commercial plant-based dye by LC-HRMS and multivariate analysis.


Asunto(s)
Espectrometría de Masas , Análisis Multivariante , Hojas de la Planta/química , Lawsonia (Planta)/química , Indigofera/química , Colorantes/química , Colorantes/análisis , Cassia/química , Cromatografía Liquida , Cromatografía Líquida de Alta Presión , Análisis de Componente Principal , Naftoquinonas/química , Naftoquinonas/análisis , Estructura Molecular
2.
Int J Mol Sci ; 25(6)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38542237

RESUMEN

Currently, scientists are increasingly focusing on utilizing the natural flora of the planet to search for and isolate individual bioactive substances that prevent various diseases, contribute to increased life expectancy, and affect all major life-supporting systems in the human body. This study describes the examination of the composition of plant raw materials from the Siberian Federal District. The research focuses on plant specimens from the root parts of Taraxacum officinale and Arctium lappa, collected in the Kemerovo region. The study determines the contents of the water-soluble vitamins B and C in the research subjects. The investigation includes assessing antioxidant properties, antimicrobial activity, and flavonoid content in extracts based on plant raw materials. All samples show a high percentage of antioxidant activity, with the highest antioxidant activity for T. officinale at 85.51 and that for A. lappa at 88.97. The results indicate low antimicrobial activity against Escherichia coli (growth inhibition zone up to 15.5 mm). Plant extracts contain significant amounts of B-group vitamins, with pyridoxine in T. officinale (156.40 µg/mL) and thiamine (46.20 µg/mL) and pyridoxine (357.10 µg/mL) in Arctium lappa. Flavonoids (rutin and quercetin) are identified in T. officinale and A. lappa extracts based on the study results.


Asunto(s)
Antiinfecciosos , Arctium , Taraxacum , Humanos , Antioxidantes/farmacología , Piridoxina , Extractos Vegetales/farmacología , Vitaminas , Antiinfecciosos/farmacología
3.
Pharm Res ; 40(12): 2859-2871, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37594593

RESUMEN

PURPOSE: This study describes the first efforts to build a spectral library to identify four cell culture media in powder form with spectra obtained with a handheld Raman spectrometer. These complex mixtures contain over 30 components and are among the most widely used cell culture media. METHODS: A total of 32 spectra were collected for the four Dulbecco's Modified Eagle Medium cell culture media and pure materials (glucose and L-glutamine) in powder form. The spectra were preprocessed using standard normal variate with second derivative, and the barcode method before performing principal component analysis (PCA). RESULTS: The PCA model differentiated the pure glucose and the cell culture media according to the glucose concentration along the first principal component. The second principal component differentiated the three cell culture media with high glucose content according to the pyruvate concentration. The correlation coefficient showed that powdered cell culture media with high glucose concentration have a higher correlation with pure glucose, when compared with the cell culture media with low glucose. CONCLUSION: The Raman spectra made it possible to differentiate the four DMEM in the cell culture media from the majority of the external samples used in the method evaluation. However, sample heterogeneity affected the predictions. Additional studies are needed to improve the method's ability to differentiate the DMEM with high glucose.


Asunto(s)
Glutamina , Ácido Pirúvico , Espectrometría Raman/métodos , Glucosa , Polvos , Técnicas de Cultivo de Célula/métodos
4.
Mar Drugs ; 21(11)2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37999415

RESUMEN

Currently, side-streams (e.g., head, backbone, tail, and intestines) generated in the fish processing industry often end up as low-value products for feed applications or even as waste. In order to upcycle such side-streams, they need to be preserved to avoid oxidative degradation of the lipids between the generation point and the valorization plant. In the cod filleting industry, three main solid side-streams: viscera, heads, and backbones, are obtained. Hence, this study aimed to identify the most efficient antioxidant for preserving the cod side-streams using a dipping-based strategy prior to pre-valorization storage at low temperatures (ice and frozen storage). The dipping solutions evaluated contained: (i) a lipophilic rosemary extract (0.05% and 0.2% in 0.9% NaCl), (ii) Duralox MANC (a mixture of rosemary extract, ascorbic acid, tocopherols, and citric acid; 2% in 0.9% NaCl), and (iii) NaCl (0.9%) w/w solution. One group was not dipped. No dipping and dipping in NaCl were included as controls. The results showed a positive effect of dipping with solutions containing antioxidants as measured by peroxide value (PV), TBA-reactive substances (TBARS), and sensory profiling, e.g., rancid odor. Moreover, the oxidative stability increased with decreased storage temperature. The cod side-streams were in general most efficiently preserved by Duralox MANC, followed by the lipophilic rosemary extract (0.2%), compared to no dipping and dipping in NaCl solution and the lower concentration of the lipophilic rosemary extract (0.05%). The efficiency of the antioxidant treatments was independent of the side-stream fraction and storage temperature. Thus, using antioxidant dipping combined with low temperature storage is an efficient preservation method for maintaining the quality of the lipids in cod solid side-streams during their pre-valorization storage.


Asunto(s)
Antioxidantes , Solución Salina , Antioxidantes/farmacología , Temperatura , Cloruro de Sodio , Ríos , Lípidos , Estrés Oxidativo
5.
Ecotoxicol Environ Saf ; 252: 114582, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36731180

RESUMEN

Phosphogypsum (PG) contains a lot of soluble phosphate (PO43--P) and fluorine ion (F-), which seriously has hindered the sustainable development of the phosphorous chemical industry. In this study, a new burning raw material (BRM) as an intermediate product in the cement production process was used for PO43--P and F- stabilize in PG. The stabilizing mechanism of PO43--P and F- were investigated by Fourier Transform infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), Scanning Electron Microscopy (SEM), X-ray fluorescence (XRF) and X-ray spectroscopy system (XPS). The effect of PG and BRM weight ratio, solid-to-liquid ratio, reaction time, and reaction temperature on the concentrations of PO43--P and F- were studied. The results showed that the concentration of F- in the PG leaching solution was 8.65 mg/L and the stabilizing efficiency of PO43--P was 99.78%, as well as the pH of the PG leaching solution was 8.12 when the weight ratio of PG and BRM was 100:2, and the solid to liquid ratio was 4:1, reacting for 24 h at the temperature of 30 â„ƒ. PO43--P and F- were mostly solidified as Ca5(PO4)3F, CaPO3(OH), Ca5(PO4)3(OH), Ca2P2O7·2H2O, CaSO4PO3(OH)·4H2O, CaF2, and CaFPO3·2H2O. Leaching test results indicated that the concentrations of PO43--P, F- and heavy metals were less than the integrated wastewater discharge standard (GB8978-1996). This study provides a new harmless treatment method for PG.


Asunto(s)
Metales Pesados , Fósforo , Espectroscopía Infrarroja por Transformada de Fourier , Fósforo/química , Metales Pesados/química , Sulfato de Calcio
6.
World J Microbiol Biotechnol ; 39(6): 144, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37004675

RESUMEN

The commercialization of fruits in markets generates a large amount of waste because they are perishable and have a short shelf life, so, they are discarded. This study aimed to provide a noble end to discarded fruits that have fermentable sugars. Banana, apple, mango and papaya residues were collected from supermarkets and underwent an enzymatic hydrolysis process. The ability of four pectinases, two amylases, one xylanase and one cellulase to release reducing sugars from fruit biomass before fermentation with two yeast strains (S. cerevisiae CAT-1 and S. cerevisiae Angel) for bioethanol production was investigated, obtaining a total of RS (Reducing sugar) of 268.08 mg/mL in banana residues. A fermentation with yeast S. cerevisiae CAT-1 resulted in 98% consumption of RS and the production of a total of 28.02 g/L of ethanol. Furthermore, fermentation with the yeast S. cerevisiae Angel, resulted in 97% RS consumption and 31.87 g/L ethanol production, which was the best result obtained throughout all the tests of hydrolysis, highlighting the banana residue as a promising biomass for the production of bioethanol.


Asunto(s)
Frutas , Saccharomyces cerevisiae , Hidrólisis , Biomasa , Fermentación , Azúcares , Etanol , Biocombustibles
7.
J Appl Microbiol ; 132(6): 4077-4096, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35179276

RESUMEN

Scombridae fish (tuna, bonito and mackerel) have significant ecological and economic values. They are very appreciated by consumers worldwide for their high-quality flesh and for their high nutritional value. However, consumption of Scombridae fish is potentially hazardous. Indeed, several cases of infections and toxicity linked to the consumption of Scombridae fish as raw, or processed food products have been reported worldwide. In this review, we presented the most common health risks associated with Scombridae fish consumption. Diseases associated with the consumption of these fish are generally infectious or toxic and are caused by biological hazards, such as bacteria, viruses, parasites or chemicals hazards that enter the body through contaminated fish (polycyclic aromatic hydrocarbons, histamine) or by physical contaminants, such as heavy metals. The risks of contamination exist throughout the food chain, from primary production to the preparation of products for consumption.


Asunto(s)
Contaminación de Alimentos , Metales Pesados , Animales , Peces , Contaminación de Alimentos/análisis , Metales Pesados/toxicidad , Alimentos Marinos , Atún/microbiología
8.
J Environ Manage ; 309: 114677, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35151134

RESUMEN

This work presents a systematic characterisation of 100 waste mobile phones (73 feature phones and 23 smartphones) produced between 1989 and 2016. All items were inventoried and the evolvement of the relative abundances of their macro-components (mechanic and electro-mechanic parts, electronics and others) and materials was investigated. The average lifetime was 15.1 years for feature phones and 6.4 years for smartphones. The main component was plastic, on average 46%-wt. in feature phones and 37%-wt. in smartphones; over the years electronics' and plastic's amounts decreased (respectively 80% and 70%), while metal components' amount increased (12%). A cost-benefit analysis explored the profitability of the management of waste mobile phones through manual dismantling followed by the sale of the separated components and materials. The average cost of manual dismantling was estimated as 6.93 € per item according to EU average labour costs and 1.50 € per item based on minimum EU labour costs. According to the performed economic analysis, the actual market prices for the potentially recoverable materials and components of waste mobile phones were not able (particularly mixed plastics) to counterbalance the costs of manual dismantling according to the European standard labour costs.


Asunto(s)
Teléfono Celular , Residuos Electrónicos , Residuos Electrónicos/análisis , Metales , Plásticos , Reciclaje
9.
J Environ Manage ; 314: 114984, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35430516

RESUMEN

The European Union (EU) depends on third markets to supply many important raw materials. Increasing the circularity of critical raw materials within the EU is important not only from an environmental perspective, but also as a competitive advantage for the EU economy. In the case of boron, the EU's import dependency is about 100%. This work aims to evaluate the boron recovery from seawater desalination plants (SWDP) brines using ion-exchange resins in a circular economy approach. Commercial boron selective resins Purolite S108, DIAION CRB03 and CRB05 were tested and compared on batch and dynamic experiments. Thermodynamic and kinetic experiments were performed, and results were fitted by linear and non-linear models. After a comparison, results showed a good fit to the Langmuir isotherm and the pseudo-second order model, respectively, for all the commercial resins tested. The DIAION CRB03 resin presented higher sorption capacity and percentage of boron sorbed than the other resins and was selected as the best option for boron recovery from SWDP brine. Dynamic experiments in fixed bed column using DIAION CRB03 resulted in a sorption capacity of 13 mg/g of resin, a boron recovery of 98% and a concentration factor of 30, for an initial boron concentration of 50 mg/L. In addition, an economic analysis was carried out as a preliminary estimate of the revenues obtained from the production of boric acid from the brine produced by El Prat desalination plant.


Asunto(s)
Boro , Resinas de Intercambio Iónico , Adsorción , Concentración de Iones de Hidrógeno , Intercambio Iónico , Sales (Química) , Agua de Mar
10.
Molecules ; 27(16)2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-36014498

RESUMEN

Biosynthesis of phytochemicals in leaves of Brassica can be initiated by abiotic factors. The aim of the study was to investigate elicitor treatments to add value to waste of cabbage. A leaf waste fraction from industrial trimming of head cabbage was exposed to UV radiation (250-400 nm, 59 and 99 kJ∙m-2, respectively), photosynthetic active radiation (PAR, 400-700 nm, 497 kJ∙m-2), and ultrasound in water bath (35 kHz, at 15, 30 and 61 kJ∙l-1 water), in order to improve nutraceutical concentration. UV was more effective than PAR to increase the level of flavonols (2 to 3-fold higher) and hydroxycinnamate monosaccharides (1 to 10-fold higher). PAR was three times as effective as UV to increase anthocyanins. Interaction of PAR + UV increased antioxidant activity (30%), the content of five phenolics (1.4 to 10-fold higher), and hydroxycinnamic monosaccharides (compared with PAR or UV alone). Indoles were reduced (40-52%) by UV, but the other glucosinolates (GLS) were unaffected. Ultrasound did not influence any parameters. The results are important for white cabbage by-products by demonstrating that UV + PAR can be successfully used as an effectual tool to increase important phenolics and antioxidant activity of waste fraction leaves without an adverse effect on the main GLS.


Asunto(s)
Brassica , Glucosinolatos , Antocianinas , Antioxidantes/farmacología , Brassica/química , Glucosinolatos/química , Glucosinolatos/farmacología , Monosacáridos , Fenoles , Polifenoles/farmacología , Rayos Ultravioleta , Agua
11.
Waste Manag Res ; 40(1): 96-103, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34407715

RESUMEN

Thermal delamination - meaning the removal of polymers from the module structure by a thermal process - as a first step in the recycling of crystalline silicon (c-Si) photovoltaic (PV) modules in order to enable the subsequent recovery of secondary raw materials was investigated. A correlation between treatment temperature and duration was established by an iterative process. Furthermore, chemical characterization of the resulting solid outputs (glass, cell, ribbons and residues) was performed in order to assess their further processing options. Additionally, the effect of removing the backsheet as a pre-treatment before the actual delamination process was investigated in relation to the aforementioned aspects of treatment duration and output quality. Results show that increased temperatures reduce the necessary treatment duration (65 minutes at 500°C, 33 minutes at 600°C) while generating the same output quality. The backsheet removal leads to an additional duration decrease of more than 45% at each considered temperature, while also having positive effects relating to fewer solid residues and easier flue gas handling. In regard to the main output specifications no significant influence of the pre-treatment is observed. Overall thermal delamination can be seen as a feasible method in order to obtain high value secondary raw materials from c-Si PV modules, while backsheet removal as pre-treatment should be considered as advantageous from multiple standpoints.


Asunto(s)
Reciclaje , Silicio , Vidrio , Temperatura
12.
J Environ Manage ; 287: 112311, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33752048

RESUMEN

Despite efforts to utilise bauxite residue, the amount of red mud stored in reservoirs is increasing. This paper aims to evaluate the potential of red mud and other sludge waste types as a soil substitute by monitoring plant development. Pot experiments were carried out testing two types of mixtures: dredging sludge from Lake Balaton mixed with garden soil and the sewage sludge and soil blend. These were then treated with red mud (15 and 30% w/w). The plants were under-, while the roots were more developed in the sewage sludge mix than the dredging sludge blend and the control soil. In the sewage amendment, the phosphorous content increased while the calcium content was lower than in the other soil types and the optimum. The metals uptake of the plants was a factor of the red mud quantity. Lead, nickel, titanium and silicon had elevated concentrations parallel to higher red mud content, but only the nickel exceeded the threshold of the Hungarian legislation. Silicon and titanium were beneficial for plant growth, compensating for the potentially toxic effects of lead and nickel. Results suggest that the red mud in a mixture with either sewage sludge or dredging sludge can act as catalysts for the growth rate of test plants, allowing their utilisation as secondary raw materials.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Hungría , Metales Pesados/análisis , Aguas del Alcantarillado , Sinapis , Suelo , Contaminantes del Suelo/análisis
13.
Molecules ; 26(8)2021 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33917716

RESUMEN

The article is a summary of scientific reports from the last 16 years (2005-2021) on the use of capillary electrophoresis to analyze polyphenolic compounds, coumarins, amino acids, and alkaloids in teas or different parts of plants used to prepare aqueous infusions, commonly known as "tea" or decoctions. This literature review is based on PRISMA guidelines and articles selected in base of criteria carried out using PICOS (Population, Intervention, Comparison, Outcome, Study type). The analysis showed that over 60% of articles included in this manuscript comes from China. The literature review shows that for the selective electrophoretic separation of polyphenolic and flavonoid compounds, the most frequently used capillary electromigration technique is capillary electrophoresis with ultraviolet detection. Nevertheless, the use of capillary electrophoresis-mass spectrometry allows for the sensitive determination of analytes with a lower limit of detection and gives hope for routine use in the analysis of functional foods. Moreover, using the modifications in electrochemical techniques allows methods sensitivity reduction along with the reduction of analysis time.


Asunto(s)
Electroforesis Capilar/métodos , Fitoquímicos/análisis , Plantas/química , Electroquímica , Espectrometría de Masas , Microfluídica
14.
Molecules ; 27(1)2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-35011281

RESUMEN

Humankind is facing a climate and energy crisis which demands global and prompt actions to minimize the negative impacts on the environment and on the lives of millions of people. Among all the disciplines which have an important role to play, chemistry has a chance to rethink the way molecules are made and find innovations to decrease the overall anthropic footprint on the environment. In this paper, we will provide a review of the existing knowledge but also recent advances on the manufacturing and end uses of acrylamide-based polymers following the "green chemistry" concept and 100 years after the revolutionary publication of Staudinger on macromolecules. After a review of raw material sourcing options (fossil derivatives vs. biobased), we will discuss the improvements in monomer manufacturing followed by a second part dealing with polymer manufacturing processes and the paths followed to reduce energy consumption and CO2 emissions. In the following section, we will see how the polyacrylamides help reduce the environmental footprint of end users in various fields such as agriculture or wastewater treatment and discuss in more detail the fate of these molecules in the environment by looking at the existing literature, the regulations in place and the procedures used to assess the overall biodegradability. In the last section, we will review macromolecular engineering principles which could help enhance the degradability of said polymers when they reach the end of their life cycle.

15.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(2): 205-209, 2021 Apr 08.
Artículo en Zh | MEDLINE | ID: mdl-33825383

RESUMEN

The registration system of medical device Master Files is established to solve the problem that the outsourcing suppliers are not willing to cooperate with the device applicants in the process of providing medical device application documents. After a brief introduction of Master Files systems established by foreign regulatory agencies, this article focuses on the research of establishing a medical device Master Files registration system in China. The results show that the establishment of Chinese Master Files registration system can both improve the standardization and convenience of outsourcing activities of medical devices, and satisfy the needs of the development of medical device industry and regulatory system. At the same time, the probability of additional risk caused by the implementation of the system is low. Therefore, it is expected that the benefits of the system to promote public health outweigh the potential risks, which demonstrates that establishment of the system has important application values.


Asunto(s)
Industrias , China , Estándares de Referencia
16.
BMC Biotechnol ; 20(1): 22, 2020 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-32375769

RESUMEN

BACKGROUND: In Norway, 3 million discarded egg-laying hens are destructed annually, which equals 1500 tons pure hen meat. Due to the slaughter methods used, this raw material is handled as a high-risk waste, while in reality it constitutes a source of valuable components like proteins and lipids. METHODS: This study assess different processing methods (thermal treatment, enzymatic hydrolysis and silaging) for utilization of discarded egg-laying hens for the production of ingredients for human consumption and animal feed. The processing methods were evaluated on the basis of quantity and quality of the obtained products. RESULTS: Thermal treatment and enzymatic hydrolysis resulted in extraction of good quality lipids from the raw material. The separated oil (50.1-82.3% of the total lipid content in the raw material) was of high quality based on the content of free fatty acids (≤ 1.0%) and total oxidation value (≤ 3.9). Enzymatic hydrolysis also enabled separation of protein in the form of protein hydrolysate. Addition of Protamex and Papain+Bromelain significantly (p ≤ 0.05) increased the protein content (85.1-94.6%) and decreased the lipid content (0.3-1.1%) in the hydrolysate compared to autolysis (protein content: 64.8-72.3%, lipid content: 1.0-2.6%). Silaging increased the protein digestibility (63.2-79.7% compared to 57.3-66.2% for untreated raw material), and thus constitutes a good method for utilizing the protein content of the raw material for animal feed. CONCLUSION: The biotechnological processing methods thermal treatment, enzymatic hydrolysis and silaging can be used to increase the utilization of discarded egg-laying hens for production of ingredients for human consumption and animal feed.


Asunto(s)
Alimentación Animal/análisis , Grasas/metabolismo , Proteínas/metabolismo , Animales , Pollos , Digestión , Femenino , Manipulación de Alimentos , Calor , Ensilaje/análisis
17.
Cytotherapy ; 22(11): 669-676, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32713719

RESUMEN

A key hurdle to ensuring patient access to cell and gene therapies (CGTs) and continued growth of the industry is the management of raw materials. The combination of rapid growth, individual product and process complexity and limited industry-specific guidance or awareness presents non-obvious risk mitigation challenges for transitioning from development to clinical application. Understanding, assessing and mitigating the varied raw material risks for CGT products during product and clinical development are critical for ensuring smooth transitions into commercialization and for preventing interruption of product supply to patients. This article presents a risk-based approach driven by concerns for patient safety that can help focus and coordinate efforts to address the most critical risk factors. Highlighted are some of the highest risk materials common to the manufacture of many CGTs, including the primary starting material, culture media, reagents and single-use components. Using a hypothetical gene-edited cell therapy as an example, we describe the general manufacturing process and subsequently incorporate the described methodology to perform a sample risk assessment. The practical approach described herein is intended to assist CGT manufacturers and suppliers in actively assessing materials early in development to provide a basic starting point for mitigating risks experienced when translating CGT products for clinical and long-term commercial application.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos/economía , Comercio , Medición de Riesgo , Terapia Genética , Humanos , Seguridad del Paciente , Factores de Riesgo
18.
J Hum Evol ; 143: 102787, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32344263

RESUMEN

Changes in the ways Paleolithic foragers exploited raw material sources are linked to mobility, the demands of production, and investment in quarrying. Here, we analyze the use of raw materials in a long series of superimposed layers from Tabun Cave dating to the Middle Pleistocene, attributed to the Lower and Middle Paleolithic periods. Using the cortex preserved on the surfaces of artifacts, including blanks, tools and cores, we distinguished between flints obtained from primary and secondary geological contexts. The results from Tabun Cave indicate that the exploitation of secondary sources was fairly common during the earlier part of the Lower Paleolithic sequence. It decreased during the later part of the Acheulo-Yabrudian complex of the Lower Paleolithic, coinciding with growing use of predetermined technological strategies, which demand high-quality raw materials. By the Middle Paleolithic, primary and secondary raw materials are generally designated for different reduction trajectories, suggesting a growing distinction and formalization of technological strategies. The need for the 'best' stone for Middle Paleolithic laminar and Levallois production may have necessitated increased investment in raw material procurement. During most of the Lower Paleolithic, raw material needs could have been met easily through a purely embedded strategy, in which raw material was collected while focusing on other activities. Starting in the late Acheulo-Yabrudian and especially during the Middle Paleolithic, the focus on primary geological contexts may have demanded greater planning of visits to raw material outcrops. In other words, in the Middle Paleolithic and possibly already during the very end of the Lower Paleolithic, raw material procurement had greater influence on patterns of movement through the landscape.


Asunto(s)
Arqueología , Evolución Cultural , Hombre de Neandertal/psicología , Tecnología , Comportamiento del Uso de la Herramienta , Animales , Cuevas , Humanos , Israel
19.
J Hum Evol ; 142: 102744, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32199300

RESUMEN

The evolution of heat treatment for stone artefact production is a subject of major interest for our understanding of early modern humans. In this study, we examine the evidence from one region in Australia to provide a new record of the antiquity of heat treatment, explore chronological shifts in the frequency of heat treatment, and discuss the implications of these findings for early population dynamics and the technical knowledge early settlers might have brought with them. Until now, Australian heat treatment has only dated back 25000 years. This study of the Willandra Lakes, including Lake Mungo, has identified the oldest systematic evidence of heat treatment yet reported in Australia, dating to ∼42000 years. We also document time-dependent directional change in the frequency of the practice. At those early times, with over 60% of all silcrete artefacts heat-treated, we hypothesize that the practice was mastered and integrated as a recurrent technical solution to the complexities of knapping silcrete. Over time, the use of heat treatment decreased progressively until less than 10% of the artefacts were heat-treated in the terminal Holocene. This trajectory has implications for understanding the antiquity of heat treatment on the Australian continent and for investigating the factors that governed its use.


Asunto(s)
Arqueología , Incendios , Tecnología , Sedimentos Geológicos/análisis , Calor , Humanos , Lagos , Nueva Gales del Sur
20.
J Environ Manage ; 254: 109796, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31731026

RESUMEN

Plastic films can be considered as a high-value auxiliary material in agriculture with multiple important uses to fulfil, including covering films in greenhouse cultivation system. Such an application enables several benefits and, therefore, it is going through an important upsurge, especially in regions where protected crop cultivation is highly widespread. However, the increased demand for these covering films arouses concerns for their post-use treatment with regard to both the consumption of Non-Renewable Primary Energy (NRPE) resources and the emission of Greenhouse Gases (GHGs). Therefore, environmental analysis is needed to find and follow cleaner paths for the management and treatment of this kind of Agricultural Plastic Waste (APW), especially in the light of the gap currently existing in the specialised literature. In this context, this paper reports upon findings from a combined Life Cycle Assessment (LCA) of single environmental issues (i.e., energy and water consumption, and GHG emissions) applied to a Sicilian firm, representative of APW collection and recycling to obtain Low-Density Polyethylene (LDPE) granules. The results showed that electricity consumption for the whole recycling process is the most NRPE resource demanding and the most GHG emitting input item. Moreover, the washing phase of disused covering films is the highest water demanding within the recycling process. Potential improvements could be achieved by shifting from fossil energy source to renewable one. The installation of a wind power plant would lead to around 56% and 85% reduction in NRPE resource exploitation and GHG emission, respectively. Finally, despite the huge consumption of water and NRPE resources and the resulting GHG emissions, the production of recycled-LDPE granules is far more sustainable than the virgin counterpart.


Asunto(s)
Plásticos , Reciclaje , Agricultura , Fuentes Generadoras de Energía , Efecto Invernadero , Centrales Eléctricas
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