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1.
Cancer ; 130(17): 2978-2987, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38718029

RESUMEN

BACKGROUND: The polygenic risk score (PRS) allows the quantification of the polygenic effect of many low-penetrance alleles on the risk of breast cancer (BC). This study aimed to evaluate the performance of two sets comprising 77 or 313 low-penetrance loci (PRS77 and PRS313) in patients with BC in the Czech population. METHODS: In a retrospective case-control study, variants were genotyped from both the PRS77 and PRS313 sets in 1329 patients with BC and 1324 noncancer controls, all women without germline pathogenic variants in BC predisposition genes. Odds ratios (ORs) were calculated according to the categorical PRS in individual deciles. Weighted Cox regression analysis was used to estimate the hazard ratio (HR) per standard deviation (SD) increase in PRS. RESULTS: The distributions of standardized PRSs in patients and controls were significantly different (p < 2.2 × 10-16) with both sets. PRS313 outperformed PRS77 in categorical and continuous PRS analyses. For patients in the highest 2.5% of PRS313, the risk reached an OR of 3.05 (95% CI, 1.66-5.89; p = 1.76 × 10-4). The continuous risk was estimated as an HRper SD of 1.64 (95% CI, 1.49-1.81; p < 2.0 × 10-16), which resulted in an absolute risk of 21.03% at age 80 years for individuals in the 95th percentile of PRS313. Discordant categorization into PRS deciles was observed in 248 individuals (9.3%). CONCLUSIONS: Both PRS77 and PRS313 are able to stratify individuals according to their BC risk in the Czech population. PRS313 shows better discriminatory ability. The results support the potential clinical utility of using PRS313 in individualized BC risk prediction.


Asunto(s)
Neoplasias de la Mama , Predisposición Genética a la Enfermedad , Humanos , Femenino , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Herencia Multifactorial/genética , Adulto , Medición de Riesgo/métodos , República Checa/epidemiología , Factores de Riesgo , Puntuación de Riesgo Genético
2.
Endoscopy ; 55(3): 276-293, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36696907

RESUMEN

Obesity is a chronic, relapsing, degenerative, multifactorial disease that is associated with many co-morbidities. The global increasing burden of obesity has led to calls for an urgent need for additional treatment options. Given the rapid expansion of bariatric endoscopy and bariatric surgery across Europe, the European Society of Gastrointestinal Endoscopy (ESGE) has recognized the need to formalize and enhance training in bariatric endoscopy and the endoscopic treatment of bariatric surgical adverse events. This manuscript represents the outcome of a formal Delphi process resulting in an official Position Statement of the ESGE and provides a framework to develop and maintain skills in bariatric endoscopy and the endoscopic treatment of bariatric surgical adverse events. This curriculum is set out in terms of the prerequisites prior to training, minimum number of procedures, the steps for training and quality of training, and how competence should be defined and evidenced before independent practice. 1: ESGE recommends that every endoscopist should have achieved competence in upper gastrointestinal endoscopy before commencing training in bariatric endoscopy and the endoscopic treatment of bariatric surgical adverse events. 2: Trainees in bariatric endoscopy and the endoscopic treatment of the complications of bariatric surgery should have basic knowledge of the definition, classification, and social impact of obesity, its pathophysiology, and its related co-morbidities. The recognition and management of gastrointestinal diseases that are more common in patients with obesity, along with participation in multidisciplinary teams where obese patients are evaluated, are mandatory. 3 : ESGE recommends that competency in bariatric endoscopy and the endoscopic treatment of the complications of bariatric surgery can be learned by attending validated training courses on simulators initially, structured training courses, and then hands-on training in tertiary referral centers.


Asunto(s)
Cirugía Bariátrica , Endoscopía Gastrointestinal , Humanos , Endoscopía Gastrointestinal/métodos , Curriculum , Cirugía Bariátrica/efectos adversos , Obesidad/cirugía , Europa (Continente)
3.
Endoscopy ; 55(2): 121-128, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35642290

RESUMEN

BACKGROUND : Assessment of mucosal visualization during esophagogastroduodenoscopy (EGD) can be improved with a standardized scoring system. To address this need, we created the Toronto Upper Gastrointestinal Cleaning Score (TUGCS). METHODS : We developed the TUGCS using Delphi methodology, whereby an international group of endoscopy experts iteratively rated their agreement with proposed TUGCS items and anchors on a 5-point Likert scale. After each Delphi round, we analyzed responses and refined the TUGCS using an 80 % agreement threshold for consensus. We used the intraclass correlation coefficient (ICC) to assess inter-rater and test-retest reliability. We assessed internal consistency with Cronbach's alpha and item-total and inter-item correlations with Pearson's correlation coefficient. We compared TUGCS ratings with an independent endoscopist's global rating of mucosal visualization using Spearman's ρ. RESULTS : We achieved consensus with 14 invited participants after three Delphi rounds. Inter-rater reliability was high at 0.79 (95 %CI 0.64-0.88). Test-retest reliability was excellent at 0.83 (95 %CI 0.77-0.87). Cronbach's α was 0.81, item-total correlation range was 0.52-0.70, and inter-item correlation range was 0.38-0.74. There was a positive correlation between TUGCS ratings and a global rating of visualization (r = 0.41, P = 0.002). TUGCS ratings for EGDs with global ratings of excellent were significantly higher than those for EGDs with global ratings of fair (P = 0.01). CONCLUSION : The TUGCS had strong evidence of validity in the clinical setting. The international group of assessors, broad variety of EGD indications, and minimal assessor training improves the potential for dissemination.


Asunto(s)
Competencia Clínica , Endoscopía Gastrointestinal , Humanos , Reproducibilidad de los Resultados , Estudios Prospectivos , Consenso
4.
Dig Dis ; 41(3): 387-395, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36412565

RESUMEN

BACKGROUND: Inflammatory bowel disease (IBD) care and education might differ around Europe. Therefore, we conducted this European Variation In IBD PracticE suRvey (VIPER) to investigate potential differences between countries. METHODS: This trainee-initiated survey, run through SurveyMonkey®, consisted of 47 questions inquiring basic demographics, IBD training, and clinical care. Results were compared according to gross domestic product (GDP) per capita, for which countries were divided into 2 groups (low/high income, according to the World Bank). RESULTS: The online survey was completed by 1,285 participants from 40 European countries, with a majority of specialists (65.3%) working in academic institutions (50.4%). Significant differences in IBD-specific training (55.9% vs. 38.4%), as well as availability of IBD units (58.4% vs. 39.7%) and multidisciplinary meetings (73.2% vs. 40.1%), were observed between respondees from high and low GDP countries (p < 0.0001). In high GDP countries, IBD nurses are more common (85.9% vs. 36.0%), also mirrored by more nurse-led IBD clinics (40.6% vs. 13.7%; p < 0.0001). IBD dieticians (33.4% vs. 16.5%) and psychologists (16.8% vs. 7.5%) are mainly present in high GDP countries (p < 0.0001). In the current COVID era, telemedicine is available in 73.2% versus 54.1% of the high/low GDP countries, respectively (p < 0.0001). Treat-to-target approaches are implemented everywhere (85.0%), though access to biologicals and small molecules differs significantly. CONCLUSION: Much variability in IBD practice exists across Europe, with marked differences between high and low GDP countries. Further work is required to help address some of these inequalities, aiming to improve and standardize IBD care and training across Europe.


Asunto(s)
Productos Biológicos , COVID-19 , Enfermedades Inflamatorias del Intestino , Humanos , Enfermedades Inflamatorias del Intestino/epidemiología , Enfermedades Inflamatorias del Intestino/terapia , Europa (Continente)/epidemiología , Encuestas y Cuestionarios
5.
Sensors (Basel) ; 23(17)2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37687789

RESUMEN

In the past decade, Long-Range Wire-Area Network (LoRaWAN) has emerged as one of the most widely adopted Low Power Wide Area Network (LPWAN) standards. Significant efforts have been devoted to optimizing the operation of this network. However, research in this domain heavily relies on simulations and demands high-quality real-world traffic data. To address this need, we monitored and analyzed LoRaWAN traffic in four European cities, making the obtained data and post-processing scripts publicly available. For monitoring purposes, we developed an open-source sniffer capable of capturing all LoRaWAN communication within the EU868 band. Our analysis discovered significant issues in current LoRaWAN deployments, including violations of fundamental security principles, such as the use of default and exposed encryption keys, potential breaches of spectrum regulations including duty cycle violations, SyncWord issues, and misaligned Class-B beacons. This misalignment can render Class-B unusable, as the beacons cannot be validated. Furthermore, we enhanced Wireshark's LoRaWAN protocol dissector to accurately decode recorded traffic. Additionally, we proposed the passive reception of Class-B beacons as an alternative timebase source for devices operating within LoRaWAN coverage under the assumption that the issue of misaligned beacons can be addressed or mitigated in the future. The identified issues and the published dataset can serve as valuable resources for researchers simulating real-world traffic and for the LoRaWAN Alliance to enhance the standard to facilitate more reliable Class-B communication.

6.
Int J Mol Sci ; 23(14)2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35887000

RESUMEN

A colorectal adenoma, an aberrantly growing tissue, arises from the intestinal epithelium and is considered as precursor of colorectal cancer (CRC). In this study, we investigated structural and numerical chromosomal aberrations in adenomas, hypothesizing that chromosomal instability (CIN) occurs early in adenomas. We applied array comparative genomic hybridization (aCGH) to fresh frozen colorectal adenomas and their adjacent mucosa from 16 patients who underwent colonoscopy examination. In our study, histologically similar colorectal adenomas showed wide variability in chromosomal instability. Based on the obtained results, we further stratified patients into four distinct groups. The first group showed the gain of MALAT1 and TALAM1, long non-coding RNAs (lncRNAs). The second group involved patients with numerous microdeletions. The third group consisted of patients with a disrupted karyotype. The fourth group of patients did not show any CIN in adenomas. Overall, we identified frequent losses in genes, such as TSC2, COL1A1, NOTCH1, MIR4673, and GNAS, and gene gain containing MALAT1 and TALAM1. Since long non-coding RNA MALAT1 is associated with cancer cell metastasis and migration, its gene amplification represents an important event for adenoma development.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Lesiones Precancerosas , ARN Largo no Codificante , Adenoma/genética , Adenoma/patología , Inestabilidad Cromosómica , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Hibridación Genómica Comparativa , Humanos , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , ARN Largo no Codificante/genética
7.
Carcinogenesis ; 42(3): 378-394, 2021 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-33319241

RESUMEN

One of the principal mechanisms of chemotherapy resistance in highly frequent solid tumors, such as colorectal cancer (CRC), is the decreased activity of drug transport into tumor cells due to low expression of important membrane proteins, such as solute carrier (SLC) transporters. Sequence complementarity is a major determinant for target gene recognition by microRNAs (miRNAs). Single-nucleotide polymorphisms (SNPs) in target sequences transcribed into messenger RNA may therefore alter miRNA binding to these regions by either creating a new site or destroying an existing one. miRSNPs may explain the modulation of expression levels in association with increased/decreased susceptibility to common diseases as well as in chemoresistance and the consequent inter-individual variability in drug response. In the present study, we investigated whether miRSNPs in SLC transporter genes may modulate CRC susceptibility and patient's survival. Using an in silico approach for functional predictions, we analyzed 26 miRSNPs in 9 SLC genes in a cohort of 1368 CRC cases and 698 controls from the Czech Republic. After correcting for multiple tests, we found several miRSNPs significantly associated with patient's survival. SNPs in SLCO3A1, SLC22A2 and SLC22A3 genes were defined as prognostic factors in the classification and regression tree analysis. In contrast, we did not observe any significant association between miRSNPs and CRC risk. To the best of our knowledge, this is the first study investigating miRSNPs potentially affecting miRNA binding to SLC transporter genes and their impact on CRC susceptibility or patient's prognosis.


Asunto(s)
Neoplasias Colorrectales/genética , MicroARNs/metabolismo , Recurrencia Local de Neoplasia/epidemiología , Transportadores de Anión Orgánico/genética , Proteínas de Transporte de Catión Orgánico/genética , Transportador 2 de Cátion Orgánico/genética , Regiones no Traducidas 3'/genética , Anciano , Sitios de Unión/genética , Estudios de Casos y Controles , Quimioterapia Adyuvante , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/terapia , Biología Computacional , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Masculino , MicroARNs/sangre , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Polimorfismo de Nucleótido Simple , Pronóstico , ARN Mensajero/sangre , ARN Mensajero/genética
8.
Mutagenesis ; 35(3): 273-281, 2020 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-31922572

RESUMEN

The chemotherapeutic efficacy in colorectal cancer (CRC) is limited due to the inter-individual variability in drug response and the development of tumour resistance. ATP-binding cassette (ABC) transporters are crucial in the development of resistance by the efflux of anticancer agents from cancer cells. In this study, we identified 14 single nucleotide polymorphisms (SNPs) in 11 ABC transporter genes acting as an expression of quantitative trait loci (eQTLs), i.e. whose variation influence the expression of many downstream genes. These SNPs were genotyped in a case-control study comprising 1098 cases and 1442 healthy controls and analysed in relation to CRC development risk and patient survival. Considering a strict correction for multiple tests, we did not observe any significant association between SNPs and CRC risk. The rs3819720 polymorphism in the ABCB3/TAP2 gene was statistically significantly associated with shorter overall survival (OS) in the codominant, and dominant models [GA vs. GG, hazard ratio (HR) = 1.48; P = 0.002; AA vs. GG, HR = 1.70; P = 0.004 and GA + AA vs. GG, HR = 1.52; P = 0.0006]. Additionally, GA carriers of the same SNP displayed worse OS after receiving 5-FU based chemotherapy. The variant allele of rs3819720 polymorphism statistically significantly affected the expression of 36 downstream genes. Screening for eQTL polymorphisms in relevant genes such as ABC transporters that can regulate the expression of several other genes may help to identify the genetic background involved in the individual response to the treatment of CRC patients.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Fluorouracilo/uso terapéutico , Transportadoras de Casetes de Unión a ATP/sangre , Anciano , Estudios de Casos y Controles , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/mortalidad , Bases de Datos Genéticas , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
9.
Gastrointest Endosc ; 92(4): 925-935, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32535193

RESUMEN

BACKGROUND AND AIMS: Although coronavirus disease 2019 (COVID-19) has affected endoscopy services globally, the impact on trainees has not been evaluated. We aimed to assess the impact of COVID-19 on procedural volumes and on the emotional well-being of endoscopy trainees worldwide. METHODS: An international survey was disseminated over a 3-week period in April 2020. The primary outcome was the percentage reduction in monthly procedure volume before and during COVID-19. Secondary outcomes included potential variation of COVID-19 impact between different continents and rates and predictors of anxiety and burnout among trainees. RESULTS: Across 770 trainees from 63 countries, 93.8% reported a reduction in endoscopy case volume. The median percentage reduction in total procedures was 99% (interquartile range, 85%-100%), which varied internationally (P < .001) and was greatest for colonoscopy procedures. Restrictions in case volume and trainee activity were common barriers. A total of 71.9% were concerned that the COVID-19 pandemic could prolonged training. Anxiety was reported in 52.4% of respondents and burnout in 18.8%. Anxiety was independently associated with female gender (odds ratio [OR], 2.15; P < .001), adequacy of personal protective equipment (OR, 1.75; P = .005), lack of institutional support for emotional health (OR, 1.67; P = .008), and concerns regarding prolongation of training (OR, 1.60; P = .013). Modifying existing national guidelines to support adequate endoscopy training during the pandemic was supported by 68.9%. CONCLUSIONS: The COVID-19 pandemic has led to restrictions in endoscopic volumes and endoscopy training, with high rates of anxiety and burnout among endoscopy trainees worldwide. Targeted measures by training programs to address these key issues are warranted to improve trainee well-being and support trainee education.


Asunto(s)
Ansiedad/epidemiología , Betacoronavirus , Agotamiento Profesional/epidemiología , Infecciones por Coronavirus/epidemiología , Endoscopía/educación , Internacionalidad , Neumonía Viral/epidemiología , Adulto , COVID-19 , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Endoscopía/estadística & datos numéricos , Femenino , Humanos , Masculino , Pandemias/prevención & control , Neumonía Viral/prevención & control , Neumonía Viral/transmisión , SARS-CoV-2 , Encuestas y Cuestionarios
10.
Int J Mol Sci ; 21(15)2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32756484

RESUMEN

The phenotypic effects of single nucleotide polymorphisms (SNPs) in the development of sporadic solid cancers are still scarce. The aim of this review was to summarise and analyse published data on the associations between SNPs in mismatch repair genes and various cancers. The mismatch repair system plays a unique role in the control of the genetic integrity and it is often inactivated (germline and somatic mutations and hypermethylation) in cancer patients. Here, we focused on germline variants in mismatch repair genes and found the outcomes rather controversial: some SNPs are sometimes ascribed as protective, while other studies reported their pathological effects. Regarding the complexity of cancer as one disease, we attempted to ascertain if particular polymorphisms exert the effect in the same direction in the development and treatment of different malignancies, although it is still not straightforward to conclude whether polymorphisms always play a clear positive role or a negative one. Most recent and robust genome-wide studies suggest that risk of cancer is modulated by variants in mismatch repair genes, for example in colorectal cancer. Our study shows that rs1800734 in MLH1 or rs2303428 in MSH2 may influence the development of different malignancies. The lack of functional studies on many DNA mismatch repair SNPs as well as their interactions are not explored yet. Notably, the concerted action of more variants in one individual may be protective or harmful. Further, complex interactions of DNA mismatch repair variations with both the environment and microenvironment in the cancer pathogenesis will deserve further attention.


Asunto(s)
Reparación de la Incompatibilidad de ADN/genética , Homólogo 1 de la Proteína MutL/genética , Proteína 2 Homóloga a MutS/genética , Neoplasias/genética , Metilación de ADN/genética , Progresión de la Enfermedad , Mutación de Línea Germinal/genética , Humanos , Neoplasias/patología , Polimorfismo de Nucleótido Simple/genética
11.
Int J Mol Sci ; 21(9)2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32380676

RESUMEN

Colorectal cancer (CRC) is a malignant disease with an incidence of over 1.8 million new cases per year worldwide. CRC outcome is closely related to the respective stage of CRC and is more favorable at less advanced stages. Detection of early colorectal adenomas is the key to survival. In spite of implemented screening programs showing efficiency in the detection of early precancerous lesions and CRC in asymptomatic patients, a significant number of patients are still diagnosed in advanced stages. Research on CRC accomplished during the last decade has improved our understanding of the etiology and development of colorectal adenomas and revealed weaknesses in the general approach to their detection and elimination. Recent studies seek to find a reliable non-invasive biomarker detectable even in the blood. New candidate biomarkers could be selected on the basis of so-called liquid biopsy, such as long non-coding RNA, microRNA, circulating cell-free DNA, circulating tumor cells, and inflammatory factors released from the adenoma into circulation. In this work, we focused on both genetic and epigenetic changes associated with the development of colorectal adenomas into colorectal carcinoma and we also discuss new possible biomarkers that are detectable even in adenomas prior to cancer development.


Asunto(s)
Adenoma/genética , Biomarcadores de Tumor , Neoplasias Colorrectales/genética , Susceptibilidad a Enfermedades , Adenoma/diagnóstico , Adenoma/metabolismo , Animales , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/metabolismo , Detección Precoz del Cáncer , Regulación Neoplásica de la Expresión Génica , Variación Genética , Humanos
15.
Carcinogenesis ; 39(11): 1359-1367, 2018 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-30277504

RESUMEN

MicroRNA (miRNA) profiling represents a promising source of cancer-related biomarkers. miRNA signatures are specific for each cancer type and subgroups of patients with diverse treatment sensitivity. Yet this miRNA potential has not been satisfactorily explored in rectal cancer (RC). The aim of the study was to identify the specific miRNA signature with clinical and therapeutic relevance for RC. Expressions of 2555 miRNA were examined in 20 pairs of rectal tumors and matched non-malignant tissues by 3D-Gene Toray microarray. Candidate miRNAs were validated in an independent cohort of 100 paired rectal tissues and in whole plasma and exosomes of 100 RC patients. To study the association of miRNA profile with therapeutic outcomes, plasma samples were taken repeatedly over a time period of 1 year reflecting thus patients' treatment responses. Finally, the most prominent miRNAs were investigated in vitro for their involvement in cell growth. We identified RC-specific miRNA signature that distinguishes responders from non-responders to adjuvant chemotherapy. A predominant part of identified miRNAs was represented by the members of miR-17/92 cluster. Upregulation of miRNA-17, -18a, -18b, -19a, -19b, -20a, -20b and -106a in tumor was associated with higher risk of tumor relapse and their overexpression in RC cell lines stimulated cellular proliferation. Examination of these miRNAs in plasma exosomes showed that their levels differed between RC patients and healthy controls and correlated with patient's treatment response. miRNAs from miR-17/92 cluster represent a non-invasive biomarker to predict posttreatment prognosis in RC patients.


Asunto(s)
Antineoplásicos/uso terapéutico , MicroARNs/genética , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/genética , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Proliferación Celular/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Neoplasias del Recto/mortalidad , Resultado del Tratamiento
18.
Environ Manage ; 62(5): 942-954, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30143821

RESUMEN

Windbreak is one of the key factors for making the agriculture systems successful through reduced wind erosion, improved microclimate, increased biodiversity, and production potentiality of timber and agricultural crops. Even though windbreak occupies only a small part of agricultural landscape, its advantages on the ecological and economical perspective are quite high. This study evaluated the effects of three windbreak types on the wind erosion control in relation to their structural diversities, wind-speed reduction, and optical porosities in the central part of the Czech Republic. Diversity in the windbreak was evaluated based on its species diversity, vertical structure, spatial pattern, and complexities. Wind speed was measured at the different distances on the leeward side of the windbreak and one station placed on the windward side as a control. Windbreak characteristics were described by terrestrial photogrammetry method using the values of optical porosity. The timber volume of the windbreaks with rich biodiversity species ranged from 224 to 443 m3 ha-1height of the windbreak on the. Results of the windbreak efficiency showed significantly closer relationship between optical porosity and structural indices. The optical porosity significantly correlated with wind-speed reduction, especially in the lower part of the windbreak. A significant dependency of the windbreak efficiency on the tree dominant height was also observed for each windbreak type. The most significant effect on the wind-speed reduction in terms of structural indices had total diversity index and Arten-profile index describing vertical structures, which are recommended together with the optical porosity to evaluate the windbreak efficiency in controlling wind erosion.


Asunto(s)
Agricultura/métodos , Conservación de los Recursos Naturales/métodos , Árboles/crecimiento & desarrollo , Viento , Ecología , Europa (Continente)
20.
Materials (Basel) ; 17(17)2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39274789

RESUMEN

This article discusses special additive technologies, with a particular focus on the innovative binder jetting technology used to create three-dimensional objects. The theoretical part of this article defines the production process-its shortcomings and benefits. Also, the article describes process parameters and individual steps that must be optimally set for the desired result. Further, the article characterizes the most influential factors that are indispensable in the printing process-metallic powder, binder, printing parameters, and finishing operations after the printing itself. The conclusion of the theoretical part deals with various material possibilities when using binder jetting technology. In the practical part of the article, the properties of the material, the chemical composition, and the resulting accuracy of the printed samples will be verified experimentally. The information obtained will subsequently be used to identify an economically advantageous application of binder jetting technology.

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