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Formaldehyde is often applied in the industrial production of different products, such as textiles, insulation materials, or cosmetics, due to its preservative and disinfectant properties. However, formaldehyde is classified by the International Agency for Research on Cancer as carcinogenic, and there are numerous studies about the pernicious health effects that frequent exposure to formaldehyde can pose to human health. In the cosmetic industry, compounds called formaldehyde releasers are added during production, with the intent of releasing small amounts of formaldehyde over time. Although there are many methods available for the determination of formaldehyde, they are usually not suitable for the determination of free formaldehyde in cosmetics with formaldehyde releasers in their composition, as they can promote the accelerated release of formaldehyde. In this work, the gas-diffusion microextraction (GDME) technique was used for the extraction of formaldehyde from cosmetic and personal hygiene products. Acetylacetone was used as the derivatization reagent which was later used for the spectrophotometric determination of formaldehyde. The developed methodology exhibits limits of detection (1.98 mg kg-1) and quantification (6.60 mg kg-1) perfectly adequate for the determination of formaldehyde in these samples. Formaldehyde values between 6.9 ± 0.3 and 365 ± 15 mg kg-1 were found in samples containing the formaldehyde releasers DMDM hydantoin, Diazolidinyl urea, and Bronopol. Furthermore, mass spectrometry studies were performed in order to unbiasedly ensure the presence of formaldehyde in every extract. GDME proved to be an economical, simple, and robust alternative for the extraction of free formaldehyde in personal hygiene and cosmetic samples. Graphical abstract á .
Assuntos
Cosméticos/química , Formaldeído/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão , Difusão , Formaldeído/toxicidade , Humanos , Limite de Detecção , Exposição Ocupacional , Conservantes Farmacêuticos/análise , Conservantes Farmacêuticos/toxicidade , Medição de RiscoRESUMO
This study aims to investigate the effects of low-level laser therapy (LLLT) combined to a functional exercise program on treatment of FM. A double-blind and placebo-controlled randomized clinical trial composed of 22 women divided into two groups: placebo group (functional exercise program associated with placebo phototherapy n = 11) and laser group (same exercise program associated with active phototherapy; n = 11). Each session lasted from 40 to 60 min and was performed three times a week for 8 weeks. Phototherapy (808 nm, 100 mW, 4 J, and 142.85 J/cm2 per point) was bilaterally applied to different points of the quadriceps (8), hamstrings (6), and triceps sural muscles (3) immediately after each exercise session. Pre- and post-intervention evaluations regarding pain (sites, intensity, and threshold), functional performance (balance, functional tests), muscle performance (flexibility and isokinetic variables), depression, and quality of life were conducted. A reduction in pain and improvement in functional and muscular performance, depression, and quality of life were observed in both groups (p < 0.05); however, with no significant differences between them (p > 0.05). In conclusion, the benefic effects of functional exercise were not improved by combination with LLLT.
Assuntos
Terapia por Exercício , Fibromialgia/fisiopatologia , Fibromialgia/radioterapia , Terapia com Luz de Baixa Intensidade , Adulto , Terapia Combinada , Depressão/complicações , Método Duplo-Cego , Feminino , Fibromialgia/psicologia , Humanos , Pessoa de Meia-Idade , Dor/radioterapia , Limiar da Dor , Fototerapia , Qualidade de VidaRESUMO
Gas-diffusion microextraction (GDME) was applied to the extraction of vicinal diketones in bread samples aimed at the determination of these compounds by high-performance liquid chromatography with ultraviolet detection (HPLC-UV). For the first time, GDME was used for direct chemical determination in solid samples, i.e. avoiding any sample preparation prior to extraction. Different extraction parameters were studied and optimized, namely temperature, time and chemical composition of the acceptor solution where o-phenylenediamine was used as a derivatizing agent, originating quinoxalines that could be determined at 315 nm. GDME demonstrated to be a good tool for the sampling of volatile compounds in solid samples with suitable method features for butane-2,3-dione (diacetyl, DC), pentane-2,3-dione (PN) and hexane-2,3-dione (HX): low LODs (6.0, 8.6 and 12 µg kg(-1), for DC, PN and HX respectively) and LOQs (20, 29 and 38 µg kg(-1), for DC, PN and HX respectively), r(2) above 0.990, and CV around 5%. The developed methodology was applied to the determination of different bread samples and was used to reveal the decrease of α-diketones in bread during the timeframe of a week.
Assuntos
Pão/análise , Fracionamento Químico/métodos , Contaminação de Alimentos/análise , Gases/química , Cetonas/análise , Cetonas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Difusão , Temperatura , Fatores de TempoRESUMO
The occurrence of drought in soils, particularly in those contaminated by metals, poses a current threat to crops, as these factors can interact and induce unique stress responses. Therefore, this study mainly focused on understanding the crosstalk between drought and copper (Cu) stress in the physiology of the barley (Hordeum vulgare L.) plant. Using a bifactorial experimental design, seedlings were grown in a natural soil under the following treatments: plants continuously irrigated in uncontaminated soil for 14 days (control); plants continuously irrigated in Cu-contaminated soil (115 mg Cu kg-1) for 14 days (Cu); plants only irrigated during the initials 7 days of growth in uncontaminated soil (drought); plants co-exposed to Cu and drought (combined). After 14 days of growth, the results revealed that drought prevented Cu bioaccumulation in barley roots, which were still severely affected by the metal, both individually and in combination with the water deficit. Furthermore, individual and combined exposure to these stressors resulted in impaired photosynthetic performance in barley plants. Despite the increased activation of enzymatic and non-enzymatic antioxidant defence mechanisms, particularly in the green organs, the plants co-exposed to both stress factors still showed higher oxidative damage, severely impacting biomass production.
Assuntos
Hordeum , Poluentes do Solo , Secas , Plantas , Metais , Cobre/toxicidade , Solo , Poluentes do Solo/toxicidadeRESUMO
This work presents a novel application of gas-diffusion microextraction (GDME) combined with high-performance liquid chromatography with diode-array detection (HPLC-DAD) for the comprehensive analysis of volatile carbonyl compounds released from wood-based panels. GDME is a simple, fast, and environmentally friendly technique that allows the simultaneous extraction and derivatization of volatile carbonyls directly from solid samples. Commercial particleboards were analysed together with particleboard panels specifically produced using controlled conditions, materials, and reagents, to evaluate the differences in the emission profile of volatile carbonyl compounds. The effect of different production parameters, such as the type of wood particle, resin, and moisture content, on the emission profile of volatile carbonyls from particleboards was investigated using principal component analysis (PCA). The results showed that GDME-HPLC-DAD could successfully differentiate particleboards according to their emission of carbonyl compounds, such as formaldehyde, furfural, benzaldehyde, and other aliphatic carbonyls. Besides the differences on the emission of formaldehyde caused by the type of resin used, UF (urea-formaldehyde) and mUF (UF fortified with melamine), it was found that pine (Pinus pinaster Ait.) particleboards exhibit higher emissions of compounds such as acetaldehyde or hexanal when compared to the higher emissions of compounds such as furfural or benzaldehyde on the recycled particleboards.
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Aqueous extracts from Eucalyptus globulus leaves contain a wide variety of specialized metabolites, mainly polyphenols and appreciable amounts of volatile compounds, which are responsible for their diverse biological activities, such as antioxidant, antimicrobial, and allelopathic features. For this reason, several studies have been conducted to explore the composition of E. globulus leaf extracts for multiple therapeutic and commercial applications. However, so far, the available bibliographic reports only refer to the chemical composition of extracts prepared with leaves from mature trees, leaving much to clarify about the composition of juvenile eucalyptus leaf extracts. Furthermore, there is no consensus regarding the type of leaves, fresh or dried ones, to be used in the extraction procedure, considering the highest recovery of biologically active compounds. In this sense, this study aimed to characterize the chemical composition of aqueous extracts prepared with fresh and dried leaves from young and mature E. globulus trees. For this, leaf biomass from young and mature E. globulus trees was collected in three distinct places from a forest area, and after oven-drying a portion of the leaves, an extraction in hot water was carried out, followed by GC-MS and HPLC-MS/MS analyses. The results revealed that the maturity of eucalyptus trees and biomass drying significantly influenced the volatile and non-volatile composition of the aqueous extracts. Accordingly, while fresh leaf extracts of young trees had great levels of hydrolysable tannins, extracts prepared with fresh leaves from mature trees presented a wide range of terpenes. When dried leaf material was used, extracts had notorious contents of amino acids derivatives, C13 norisoprenoids, fatty and other organic acids. Overall, this study showed, for the first time, that plant maturity (young vs mature) and pre-processing (fresh vs dried) of foliar biomass of E. globulus trees need to be considered in the preparation of leaf aqueous extracts depending on the desired purposes, since major changes in what regards biologically active compounds were found.
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Turbulent radiation flow is commonplace in systems with strong, incoherent, light-matter interactions. In astrophysical contexts, photon bubble turbulence is considered a key mechanism behind enhanced radiation transport, and its importance has been widely asserted for a variety of high energy objects such as accretion disks and massive stars. Here, we show that analogous conditions to those of dense astrophysical objects can be obtained in large clouds of cold atoms, prepared in a laser-cooling experiment, driven close to a sharp electronic resonance. By accessing the spatially-resolved atom density, we are able to identify a photon bubble instability and the resulting regime of photon bubble turbulence. We also develop a theoretical model describing the coupled dynamics of both photon and atom gases, which accurately describes the statistical properties of the turbulent regime. This study thus opens the possibility of simulating radiation-dominated astrophysical systems in cold atom experiments.
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Gas-diffusion microextraction (GDME) is an innovative technique that combines the advantages of membrane-aided gas-diffusion with microextraction concepts. GDME makes uses of a novel portable and low-cost device that comprises a small, commercially available, semi-permeable membrane. Furthermore, if derivatization is integrated into the GDME concept, considerable enrichment factors can be obtained. It may become a powerful tool for any analyst who intends to quantify volatile and semi-volatile analytes in various kinds of matrices. The analysis of vicinal diketones in beer was used as a case study to show GDME applicability and capabilities. Vicinal diketones were derivatized with o-phenylenediamine and then determined by HPLC-UV. Obtained results showed good repeatability and precision with extraction periods at the minute time span.
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A new electroanalytical methodology was developed for the sensitive and selective determination of formaldehyde in wood-based products (WBPs), featuring an extraction process using a Headspace Liquid Acceptor System (HLAS), and detection by square-wave voltammetry (SWV) on unmodified screen-printed carbon electrodes (SPCEs). HLAS, here presented for the first time, captures and derivatizes formaldehyde released from the sample by using the acetylacetone reagent as acceptor solution. The product of formaldehyde with acetylacetone, in the presence of ammonium salt, is 3,5-diacetyl-1,4-dihydrolutidine (DDL) which we have found to be electrochemically active at unmodified SPCEs, generating a selective oxidation peak at +0.4 V. Detection and quantification limits of 0.57 and 1.89 mg kg-1 were obtained, together with intra- and inter-day precisions below 10% (as relative standard deviation, RSD). The methodology was used to determine formaldehyde content in seven WBPs, with similar results being obtained by the developed HLAS-SPCE method and the European standard method EN 717-3, with a profound reduction of total analysis time. The developed HLAS-SPCE combines the use of a new sample preparation procedure for volatiles with, as far as we know, the first determination of formaldehyde (as the derivative product, DDL) on unmodified SPCEs, offering a promising alternative for the determination of formaldehyde in WBPs and other samples.
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Recent studies have shown that besides the well-known T3 (triiodothyronine) and T4 (thyroxine) there might be other important thyroid hormones, in particular T0AM (thyronamine) and T1AM (3-iodothyronamine). The absence of a large number of studies showing their precise importance might be explained by the limited number of analytical methodologies available. This work aims to show an electroanalytical alternative making use of electropolymerized molecularly imprinted polymer (MIPs). The MIPs' polymerization is performed on the surface of screen-printed carbon electrodes (SPCEs), using 4-aminobenzoic acid (4-ABA) as the building and functional monomer and the analyte T0AM as the template. The step-by-step construction of the SPCE-MIP sensor was studied by cyclic voltammetry (CV) and by electrochemical impedance spectroscopy (EIS). After optimization, by means of square-wave voltammetry, the SPCE-MIP showed suitable selectivity (in comparison with other thyroid hormones and catechol amines), repeatability (intra-day of 3.9%), a linear range up to 10 µmol L-1 (0.23â¯×â¯103 µgâ¯dL-1) with an r2 of 0.998 and a limit of detection (LOD) and quantification (LOQ) of 0.081 and 0.27 µmol L-1 (1.9 and 6.2⯵gâ¯dL-1), respectively.
Assuntos
Eletroquímica/instrumentação , Impressão Molecular , Polímeros/síntese química , Carbono/química , Eletrodos , Polimerização , Polímeros/química , Impressão , Propriedades de Superfície , Tironinas/análise , Tironinas/químicaRESUMO
A new approach is proposed for the extraction and determination of carbonyl compounds in solid samples, such as wood or cork materials. Cork products are used as building materials due to their singular characteristics; however, little is known about its aldehyde emission potential and content. Sample preparation was done by using a gas-diffusion microextraction (GDME) device for the direct extraction of volatile aldehydes and derivatization with 2,4-dinitrophenylhydrazine. Analytical determination of the extracts was done by HPLC-UV, with detection at 360 nm. The developed methodology proved to be a reliable tool for aldehyde determination in cork agglomerate samples with suitable method features. Mass spectrometry studies were performed for each sample, which enabled the identification, in the extracts, of the derivatization products of a total of 13 aldehydes (formaldehyde, acetaldehyde, furfural, propanal, 5-methylfurfural, butanal, benzaldehyde, pentanal, hexanal, trans-2-heptenal, heptanal, octanal, and trans-2-nonenal) and 4 ketones (3-hydroxy-2-butanone, acetone, cyclohexanone, and acetophenone). This new analytical methodology simultaneously proved to be consistent for the identification and determination of aldehydes in cork agglomerates and a very simple and straightforward procedure.
Assuntos
Aldeídos/química , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Quercus/química , Espectrometria de Massas em Tandem/métodos , Madeira/químicaRESUMO
Salt-assisted LLE (SALLE) has been attracting growing interest in bioanalysis. The technique is particularly advantageous due to its simple and fast experimental execution using conventional laboratory equipment. Besides, SALLE uses water-miscible organic solvents making the extracts readily compatible with various analytical separation and detection techniques. This article presents a brief overview of the extraction technique and its role in bioanalysis. Some of the most relevant achievements on SALLE application to biological samples are discussed - namely the study of the main extraction parameters, the combination with other extraction techniques and the instrumental analysis of the extracts. Developments on automation, miniaturization and microextraction for SALLE procedures are also discussed as a perspective for future applications even more attractive for the analysis of biological samples.
Assuntos
Técnicas de Química Analítica/métodos , Extração Líquido-Líquido/métodos , Sais/química , Animais , Humanos , Extração Líquido-Líquido/instrumentação , MiniaturizaçãoRESUMO
Biogenic amines are nitrogenous organic compounds of low molecular weight that are either formed or metabolized in cells of living organisms and can be found in several food products, being produced mainly by amino acid decarboxylation. When ingested in high concentrations they can induce several health problems in humans. In alcoholic beverages, and especially in wine, they are formed during the vinification process as a result of the action of microorganisms. In this work it is proposed a new methodology for the determination of biogenic amines in wines, which includes a sample preparation approach based on salting-out assisted liquid-liquid extraction, the use of dansyl chloride for the derivatization and chromatographic separation by high-performance liquid chromatography with fluorimetric detection. The salting-out effect is used to promote phase separation between water and a water-miscible organic solvent, while improving the extraction of organic or inorganic species. Several extraction parameters were optimized, such as the dansyl chloride concentration, pH and the effects caused by the order in which the extraction and derivatization were performed. Extraction of amines, and consequent detection, depends on the presence of dansyl chloride in solution prior to extraction. The results showed the possibility to simultaneously perform the extraction and the derivatization, making sample preparation easier and less time-consuming. The methodology was successfully applied to the determination of biogenic amines in five wines (white, red and rosé). This method has the potential to be a good alternative to existing methods since it is cheaper, easier and simplifies the sample preparation step.
Assuntos
Aminas Biogênicas/análise , Cromatografia Líquida de Alta Pressão/métodos , Fluorometria/métodos , Extração Líquido-Líquido/métodos , Vinho/análise , Acetonitrilas/química , Compostos de Dansil/química , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Cloreto de Sódio/química , Solventes/química , Vinho/classificaçãoRESUMO
Cardamonin, as shown by the increasing number of publications, has received growing attention from the scientific community due to the expectations toward its benefits to human health. In this study, research on cardamonin is reviewed, including its natural sources, health promoting aspects, and analytical methods for its determination. Therefore, this article hopes to aid current and future researchers on the search for reliable answers concerning cardamonin's value in medicine.
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Chalconas/uso terapêutico , Magnoliopsida/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Chalconas/farmacologia , Humanos , Extratos Vegetais/farmacologiaRESUMO
The use of the salting-out effect in analytical chemistry is very diverse and can be applied to increase the volatility of the analytes in headspace extractions, to cause the precipitation of proteins in biological samples or to improve the recoveries in liquid-liquid extractions. In the latter, the salting-out process can be used to create a phase separation between water-miscible organic solvents and water. Salting-out assisted liquid-liquid extraction (SALLE) is an advantageous sample preparation technique aiming HPLC-UV analysis when developing analytical methodologies. In fact, some new extraction methodologies like QuEChERS include the SALLE concept. This manuscript discusses another point of view over SALLE with particular emphasis over acetonitrile-water mixtures for HPLC-UV analysis; the influence of the salting-out agents, their concentration and the water-acetonitrile volume ratios were the studied parameters. α-dicarbonyl compounds and beer were used as test analytes and test samples, respectively. The influence of the studied parameters was characterized by the obtained phase separation volume ratio and the fraction of α-dicarbonyls extracted to the acetonitrile phase. Results allowed the distribution of salts within three groups according to the phase separation and their extractability: (1) chlorides and acetates, (2) carbonates and sulfates and (3) magnesium sulfate; of all tested salts, sodium chloride had the highest influence on the α-dicarbonyls fraction extracted.
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Acetonitrilas/química , Extração Líquido-Líquido/métodos , Sais/química , Água/química , Carbonatos/química , Cloretos/química , Sulfatos/químicaRESUMO
A membraneless extraction module (MLEM) for the sample preparation of volatile compounds and its use for the chromatographic analysis of vicinal diketones in beer are reported. The extraction process is based on the same principles of gas diffusion (GD) and pervaporation (PV); however it does not use a membrane. This module has a lower chamber where the sample continuously flows, while volatile compounds evaporate to the headspace. Inside the module there is a suspended small reactor, where a small volume of a suitable acceptor solution is placed. This extraction module was tested in the determination of vicinal diketones (VDKs) in beer (CV=5%; LOD=4 microg L(-1)), showing applicability with real samples. Several parameters of the extraction process, such as temperature, sample flow and extraction time, were studied and optimized. This module proved to be a good tool for the sampling of volatile compounds, since the extraction is made without using a membrane avoiding all the robustness problems related with its use.
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Cerveja/análise , Fracionamento Químico/métodos , Análise de Alimentos/métodos , Cetonas/análise , Cetonas/isolamento & purificação , Cromatografia , Difusão , Gases/química , Cetonas/química , Reprodutibilidade dos Testes , VolatilizaçãoRESUMO
In this work, a recently developed extraction technique for sample preparation aiming the analysis of volatile and semi-volatile compounds named gas-diffusion microextraction (GDME) is applied in the chromatographic analysis of aldehydes in beer. Aldehydes-namely acetaldehyde (AA), methylpropanal (MA) and furfural (FA)-were simultaneously extracted and derivatized with 2,4-dinitrophenylhydrazine (DNPH), then the derivatives were separated and analyzed by high-performance liquid chromatography with spectrophotometric detection (HPLC-UV). The identity of the eluted compounds was confirmed by high-performance liquid chromatography-atmospheric pressure chemical ionization-mass-spectrometry detection in the negative ion mode (HPLC-APCI-MS). The developed methodology showed good repeatability (ca. 5%) and linearity as well as good limits of detection (AA-12.3, FA-1.5 and MA 5.4microgL(-1)) and quantification (AA-41, FA-4.9 and MA 18microgL(-1)); it also appears to be competitive in terms of speed and cost of analysis.
Assuntos
Aldeídos/análise , Cerveja/análise , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Acetaldeído/análise , Acetaldeído/química , Aldeídos/química , Furaldeído/análise , Furaldeído/química , Modelos Lineares , Sensibilidade e EspecificidadeRESUMO
This paper describes part of content-based image retrieval (CBIR) system that has been developed for mammograms. Details are presented of methods implemented to derive measures of similarity based upon structural characteristics and distributions of density of the fibroglandular tissue, as well as the anatomical size and shape of the breast region as seen on the mammogram. Well-known features related to shape, size, and texture (statistics of the gray-level histogram, Haralick's texture features, and moment-based features) were applied, as well as less-explored features based in the Radon domain and granulometric measures. The Kohonen self-organizing map (SOM) neural network was used to perform the retrieval operation. Performance evaluation was done using precision and recall curves obtained from comparison between the query and retrieved images. The proposed methodology was tested with 1,080 mammograms, including craniocaudal and mediolateral-oblique views. Precision rates obtained are in the range from 79% to 83% considering the total image set. Considering the first 50% of the retrieved mages, the precision rates are in the range from 78% to 83%; the rates are in the range from 79% to 86% considering the first 25% of the retrieved images. Results obtained indicate the potential of the implemented methodology to serve as a part of a CBIR system for mammography.
Assuntos
Mama/anatomia & histologia , Armazenamento e Recuperação da Informação , Mamografia , Reconhecimento Automatizado de Padrão , Algoritmos , Inteligência Artificial , Neoplasias da Mama/diagnóstico por imagem , Sistemas de Gerenciamento de Base de Dados , Diagnóstico por Computador , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Armazenamento e Recuperação da Informação/estatística & dados numéricos , Mamografia/métodos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/estatística & dados numéricos , Interpretação de Imagem Radiográfica Assistida por ComputadorRESUMO
In the framework of the European Aerosol Research Lidar Network to Establish an Aerosol Climatology (EARLINET), 19 aerosol lidar systems from 11 European countries were compared. Aerosol extinction or backscatter coefficient profiles were measured by at least two systems for each comparison. Aerosol extinction coefficients were derived from Raman lidar measurements in the UV (351 or 355 nm), and aerosol backscatter profiles were calculated from pure elastic backscatter measurements at 351 or 355, 532, or 1064 nm. The results were compared for height ranges with high and low aerosol content. Some systems were additionally compared with sunphotometers and starphotometers. Predefined maximum deviations were used for quality control of the results. Lidar systems with results outside those limits could not meet the quality assurance criterion. The algorithms for deriving aerosol backscatter profiles from elastic lidar measurements were tested separately, and the results are described in Part 2 of this series of papers [Appl. Opt. 43, 977-989 (2004)]. In the end, all systems were quality assured, although some had to be modified to improve their performance. Typical deviations between aerosol backscatter profiles were 10% in the planetary boundary layer and 0.1 x 10(-6) m(-1) sr(-1) in the free troposphere.
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An intercomparison of aerosol backscatter lidar algorithms was performed in 2001 within the framework of the European Aerosol Research Lidar Network to Establish an Aerosol Climatology (EARLINET). The objective of this research was to test the correctness of the algorithms and the influence of the lidar ratio used by the various lidar teams involved in the EARLINET for calculation of backscatter-coefficient profiles from the lidar signals. The exercise consisted of processing synthetic lidar signals of various degrees of difficulty. One of these profiles contained height-dependent lidar ratios to test the vertical influence of those profiles on the various retrieval algorithms. Furthermore, a realistic incomplete overlap of laser beam and receiver field of view was introduced to remind the teams to take great care in the nearest range to the lidar. The intercomparison was performed in three stages with increasing knowledge on the input parameters. First, only the lidar signals were distributed; this is the most realistic stage. Afterward the lidar ratio profiles and the reference values at calibration height were provided. The unknown height-dependent lidar ratio had the largest influence on the retrieval, whereas the unknown reference value was of minor importance. These results show the necessity of making additional independent measurements, which can provide us with a suitable approximation of the lidar ratio. The final stage proves in general, that the data evaluation schemes of the different groups of lidar systems work well.