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Article ; Online: Investigation of potential behavioral and physiological effects of caffeine on D. magna.

Nunes, Bruno / Santos, João / Dionísio, Ricardo / Dias de Alkimin, Gilberto

Environmental science and pollution research international

2022 Volume 29, Issue 28, Page(s) 43237–43250

Abstract: With the ever-increasing consumption of pharmaceutical compounds, their presence in the environment is now an undisputable reality. The majority of these compounds are released into the wild after their therapeutic use, as biotransformation products or ... ...

Abstract	With the ever-increasing consumption of pharmaceutical compounds, their presence in the environment is now an undisputable reality. The majority of these compounds are released into the wild after their therapeutic use, as biotransformation products or in their original form. The presence of this class of compounds in the environment, due to their biological properties, can exert effects on non-target organisms, with adverse consequences. In addition, some bioactive substances, such as stimulants of the central nervous system, are also used by humans as part of their diet. The adverse consequences posed by such chemicals may be permanent or transient, if the exposure to xenobiotics is halted; it is thus of the paramount importance to study effects that result from long-term exposure to toxicants, but also the recovery of organisms previously exposed to such substances, especially if such chemicals may cause some type of addiction. Caffeine (1,3,7-trimethylxanthine) is a naturally occurring alkaloid found in many plants, being one of the most common stimulant/pharmaceutical compounds found in the environment. In addition, it is addictive, and strongly consumed by humans, a factor that contributes also for its continuous presence in the aquatic environment. The aim of this study was to evaluate the effects of environmentally relevant concentrations (0.08; 0.4; 2; 10; and 50 μg/L) of caffeine on behavior and physiological parameters (that are proxies of metabolic traits, such as oxygen uptake and glycogen content), in individuals of the freshwater crustacean species Daphnia magna, of distinct ages, and with or without a recovery period in the absence of caffeine. Regarding behavior, the results indicated that caffeine exposure altered the moved distance of the test organisms, but not according to a coherent pattern; low concentrations of caffeine reduced the movement of exposed daphnids, while higher levels did not have any measurable effect on this parameter. In addition, it was possible to identify subtle withdrawal effects (animals exposed to caffeine during 21 days and kept in uncontaminated media for 2 days). Regarding the other two studied parameters, caffeine exposure did not result in any significant modification in oxygen uptake and glycogen stores/reserves of the test organisms, in animals continuously exposed, or in those subjected to a recovery period, suggesting that despite a behavioral stimulatory effect, this was not followed by any metabolic change, and no addictive effect was possible to infer. The results showed that the presence of caffeine in environmental concentrations can induce mild behavioral effects at low, albeit realistic levels, but not capable of establishing clear biochemical changes.
MeSH term(s)	Animals ; Caffeine/toxicity ; Daphnia ; Glycogen ; Oxygen ; Pharmaceutical Preparations ; Water Pollutants, Chemical/analysis
Chemical Substances	Pharmaceutical Preparations ; Water Pollutants, Chemical ; Caffeine (3G6A5W338E) ; Glycogen (9005-79-2) ; Oxygen (S88TT14065)
Language	English
Publishing date	2022-01-29
Publishing country	Germany
Document type	Journal Article
ZDB-ID	1178791-0
ISSN	1614-7499 ; 0944-1344
ISSN (online)	1614-7499
ISSN	0944-1344
DOI	10.1007/s11356-022-18695-0
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Article ; Online: Computed Tomography 4-D Valve Leaflet Assessment.

Gellada, Norman H / Mieses, Dionisio / Pimentel, Raymond

Radiologic technology

2019 Volume 91, Issue 1, Page(s) 75–78

MeSH term(s)	Computed Tomography Angiography ; Contrast Media ; Echocardiography ; Four-Dimensional Computed Tomography ; Heart Valve Diseases/diagnostic imaging ; Heart Valve Diseases/surgery ; Heart Valve Prosthesis/adverse effects ; Humans ; Iohexol ; Thrombosis/diagnostic imaging ; Transcatheter Aortic Valve Replacement/adverse effects
Chemical Substances	Contrast Media ; Iohexol (4419T9MX03)
Language	English
Publishing date	2019-08-30
Publishing country	United States
Document type	Journal Article
ZDB-ID	414079-5
ISSN	1943-5657 ; 0033-8397
ISSN (online)	1943-5657
ISSN	0033-8397
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Article: Investigation of potential behavioral and physiological effects of caffeine on D. magna

Nunes, Bruno / Santos, João / Dionísio, Ricardo / Dias de Alkimin, Gilberto

Environmental science and pollution research. 2022 June, v. 29, no. 28

2022

Abstract	With the ever-increasing consumption of pharmaceutical compounds, their presence in the environment is now an undisputable reality. The majority of these compounds are released into the wild after their therapeutic use, as biotransformation products or in their original form. The presence of this class of compounds in the environment, due to their biological properties, can exert effects on non-target organisms, with adverse consequences. In addition, some bioactive substances, such as stimulants of the central nervous system, are also used by humans as part of their diet. The adverse consequences posed by such chemicals may be permanent or transient, if the exposure to xenobiotics is halted; it is thus of the paramount importance to study effects that result from long-term exposure to toxicants, but also the recovery of organisms previously exposed to such substances, especially if such chemicals may cause some type of addiction. Caffeine (1,3,7-trimethylxanthine) is a naturally occurring alkaloid found in many plants, being one of the most common stimulant/pharmaceutical compounds found in the environment. In addition, it is addictive, and strongly consumed by humans, a factor that contributes also for its continuous presence in the aquatic environment. The aim of this study was to evaluate the effects of environmentally relevant concentrations (0.08; 0.4; 2; 10; and 50 μg/L) of caffeine on behavior and physiological parameters (that are proxies of metabolic traits, such as oxygen uptake and glycogen content), in individuals of the freshwater crustacean species Daphnia magna, of distinct ages, and with or without a recovery period in the absence of caffeine. Regarding behavior, the results indicated that caffeine exposure altered the moved distance of the test organisms, but not according to a coherent pattern; low concentrations of caffeine reduced the movement of exposed daphnids, while higher levels did not have any measurable effect on this parameter. In addition, it was possible to identify subtle withdrawal effects (animals exposed to caffeine during 21 days and kept in uncontaminated media for 2 days). Regarding the other two studied parameters, caffeine exposure did not result in any significant modification in oxygen uptake and glycogen stores/reserves of the test organisms, in animals continuously exposed, or in those subjected to a recovery period, suggesting that despite a behavioral stimulatory effect, this was not followed by any metabolic change, and no addictive effect was possible to infer. The results showed that the presence of caffeine in environmental concentrations can induce mild behavioral effects at low, albeit realistic levels, but not capable of establishing clear biochemical changes.
Keywords	Daphnia magna ; aquatic environment ; biotransformation ; caffeine ; central nervous system ; chronic exposure ; diet ; freshwater crustaceans ; glycogen ; oxygen ; pollution ; research ; therapeutics ; toxic substances ; xenobiotics
Language	English
Dates of publication	2022-06
Size	p. 43237-43250.
Publishing place	Springer Berlin Heidelberg
Document type	Article
ZDB-ID	1178791-0
ISSN	1614-7499 ; 0944-1344
ISSN (online)	1614-7499
ISSN	0944-1344
DOI	10.1007/s11356-022-18695-0
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Comparing UAV-Based Technologies and RGB-D Reconstruction Methods for Plant Height and Biomass Monitoring on Grass Ley.

Rueda-Ayala, Victor P / Peña, José M / Höglind, Mats / Bengochea-Guevara, José M / Andújar, Dionisio

Sensors (Basel, Switzerland)

2019 Volume 19, Issue 3

Abstract: ... agreement between the UAV-based, the RGB-D-based estimates and the manual height measurements on both fields ... RGB-D-based estimation correlated well with ground truth of plant height ( R 2 > 0.80 ... for both fields, and with dry biomass ( R 2 = 0.88 ), only for the timothy field. RGB-D-based estimation of plant ...

Abstract	Pastures are botanically diverse and difficult to characterize. Digital modeling of pasture biomass and quality by non-destructive methods can provide highly valuable support for decision-making. This study aimed to evaluate aerial and on-ground methods to characterize grass ley fields, estimating plant height, biomass and volume, using digital grass models. Two fields were sampled, one timothy-dominant and the other ryegrass-dominant. Both sensing systems allowed estimation of biomass, volume and plant height, which were compared with ground truth, also taking into consideration basic economical aspects. To obtain ground-truth data for validation, 10 plots of 1 m² were manually and destructively sampled on each field. The studied systems differed in data resolution, thus in estimation capability. There was a reasonably good agreement between the UAV-based, the RGB-D-based estimates and the manual height measurements on both fields. RGB-D-based estimation correlated well with ground truth of plant height ( R 2 > 0.80 ) for both fields, and with dry biomass ( R 2 = 0.88 ), only for the timothy field. RGB-D-based estimation of plant volume for ryegrass showed a high agreement ( R 2 = 0.87 ). The UAV-based system showed a weaker estimation capability for plant height and dry biomass ( R 2 < 0.6 ). UAV-systems are more affordable, easier to operate and can cover a larger surface. On-ground techniques with RGB-D cameras can produce highly detailed models, but with more variable results than UAV-based models. On-ground RGB-D data can be effectively analysed with open source software, which is a cost reduction advantage, compared with aerial image analysis. Since the resolution for agricultural operations does not need fine identification the end-details of the grass plants, the use of aerial platforms could result a better option in grasslands.
MeSH term(s)	Agriculture/methods ; Biomass ; Monitoring, Physiologic/methods ; Poaceae/anatomy & histology ; Poaceae/growth & development ; Remote Sensing Technology/methods ; Software
Language	English
Publishing date	2019-01-28
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2052857-7
ISSN	1424-8220 ; 1424-8220
ISSN (online)	1424-8220
ISSN	1424-8220
DOI	10.3390/s19030535
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Article ; Online: Influence of Wind Speed on RGB-D Images in Tree Plantations.

Andújar, Dionisio / Dorado, José / Bengochea-Guevara, José María / Conesa-Muñoz, Jesús / Fernández-Quintanilla, César / Ribeiro, Ángela

Sensors (Basel, Switzerland)

2017 Volume 17, Issue 4

Abstract: Weather conditions can affect sensors' readings when sampling outdoors. Although sensors are usually set up covering a wide range of conditions, their operational range must be established. In recent years, depth cameras have been shown as a promising ... ...

Abstract	Weather conditions can affect sensors' readings when sampling outdoors. Although sensors are usually set up covering a wide range of conditions, their operational range must be established. In recent years, depth cameras have been shown as a promising tool for plant phenotyping and other related uses. However, the use of these devices is still challenged by prevailing field conditions. Although the influence of lighting conditions on the performance of these cameras has already been established, the effect of wind is still unknown. This study establishes the associated errors when modeling some tree characteristics at different wind speeds. A system using a Kinect v2 sensor and a custom software was tested from null wind speed up to 10 m·s
MeSH term(s)	Plant Leaves ; Populus ; Trees ; Wind
Language	English
Publishing date	2017-04-21
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2052857-7
ISSN	1424-8220 ; 1424-8220
ISSN (online)	1424-8220
ISSN	1424-8220
DOI	10.3390/s17040914
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Article ; Online: 3D Assessment of Vine Training Systems Derived from Ground-Based RGB-D Imagery

Hugo Moreno / José Bengochea-Guevara / Angela Ribeiro / Dionisio Andújar

Agriculture, Vol 12, Iss 798, p

2022 Volume 798

Abstract: ... pruning systems, which can increase crop yield and improve crop management. In this experiment, an RGB-D ... Pergola, Curtain, Smart Dyson and VSP). For the comparison of actual dry biomass and RGB-D volume and ... RGB-D volume to weight, Pearson’s correlation coefficient increased to 0.92. The results reveal ...

Abstract	In the field of computer vision, 3D reconstruction of crops plays a crucially important role in agriculture. On-ground assessment of geometrical features of vineyards is of vital importance to generate valuable information that enables producers to take the optimum actions in terms of agricultural management. A training system of vines ( Vitis vinifera L.), which involves pruning and a trellis system, results in a particular vine architecture, which is vital throughout the phenological stages. Pruning is required to maintain the vine’s health and to keep its productivity under control. The creation of 3D models of vineshoots is of crucial importance for management planning. Volume and structural information can improve pruning systems, which can increase crop yield and improve crop management. In this experiment, an RGB-D camera system, namely Kinect v2, was used to reconstruct 3D vine models, which were used to determine shoot volume on eight differentiated vineyard training systems: Lyre, GDC (Geneva Double Curtain), Y-Trellis, Pergola, Single Curtain, Smart Dyson, VSP (Vertical Shoot Positioned), and the head-trained Gobelet. The results were compared with dry biomass ground truth-values. Dense point clouds had a substantial impact on the connection between the actual biomass measurements in four of the training systems (Pergola, Curtain, Smart Dyson and VSP). For the comparison of actual dry biomass and RGB-D volume and its associated 3D points, strong linear fits were obtained. Significant coefficients of determination (R 2 = 0.72 to R 2 = 0.88) were observed according to the number of points connected to each training system separately, and the results revealed good correlations with actual biomass and volume values. When comparing RGB-D volume to weight, Pearson’s correlation coefficient increased to 0.92. The results reveal that the RGB-D approach is also suitable for shoot reconstruction. The research proved how an inexpensive optical sensor can be employed for rapid and reproducible 3D reconstruction ...
Keywords	depth cameras ; Kinect v2 ; 3D reconstruction ; woody crops ; Vitis vinifera L ; vineyards ; Agriculture (General) ; S1-972
Subject code	600
Language	English
Publishing date	2022-05-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: 3D Assessment of Vine Training Systems Derived from Ground-Based RGB-D Imagery

Moreno, Hugo / Bengochea-Guevara, José / Ribeiro, Angela / Andújar, Dionisio

Agriculture (Basel). 2022 May 31, v. 12, no. 6

2022

Abstract	In the field of computer vision, 3D reconstruction of crops plays a crucially important role in agriculture. On-ground assessment of geometrical features of vineyards is of vital importance to generate valuable information that enables producers to take the optimum actions in terms of agricultural management. A training system of vines (Vitis vinifera L.), which involves pruning and a trellis system, results in a particular vine architecture, which is vital throughout the phenological stages. Pruning is required to maintain the vine’s health and to keep its productivity under control. The creation of 3D models of vineshoots is of crucial importance for management planning. Volume and structural information can improve pruning systems, which can increase crop yield and improve crop management. In this experiment, an RGB-D camera system, namely Kinect v2, was used to reconstruct 3D vine models, which were used to determine shoot volume on eight differentiated vineyard training systems: Lyre, GDC (Geneva Double Curtain), Y-Trellis, Pergola, Single Curtain, Smart Dyson, VSP (Vertical Shoot Positioned), and the head-trained Gobelet. The results were compared with dry biomass ground truth-values. Dense point clouds had a substantial impact on the connection between the actual biomass measurements in four of the training systems (Pergola, Curtain, Smart Dyson and VSP). For the comparison of actual dry biomass and RGB-D volume and its associated 3D points, strong linear fits were obtained. Significant coefficients of determination (R² = 0.72 to R² = 0.88) were observed according to the number of points connected to each training system separately, and the results revealed good correlations with actual biomass and volume values. When comparing RGB-D volume to weight, Pearson’s correlation coefficient increased to 0.92. The results reveal that the RGB-D approach is also suitable for shoot reconstruction. The research proved how an inexpensive optical sensor can be employed for rapid and reproducible 3D reconstruction of vine vegetation that can improve cultural practices such as pruning, canopy management and harvest.
Keywords	Vitis vinifera ; agriculture ; biomass ; cameras ; canopy ; computer vision ; crop management ; crop yield ; phenology ; vegetation ; vines ; vineyards
Language	English
Dates of publication	2022-0531
Publishing place	Multidisciplinary Digital Publishing Institute
Document type	Article
ZDB-ID	2651678-0
ISSN	2077-0472
ISSN	2077-0472
DOI	10.3390/agriculture12060798
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Nonmedical use of d-Amphetamines and Methylphenidate in Medical Students.

Acosta, Dionisio L / Fair, Chelsea N / Gonzalez, Cinthia M / Iglesias, Maite / Maldonado, Nataly / Schenkman, Nathan / Valle, Samuel M / Velez, Jorge L / Mejia, Luis

Puerto Rico health sciences journal

2019 Volume 38, Issue 3, Page(s) 185–188

Abstract: Objective: The purpose of this study was to determine the prevalence of medical and nonmedical use of prescription attention deficit hyperactive disorder (ADHD) stimulant medication among medical students.: Materials and methods: An IRB approved 19- ... ...

Abstract	Objective: The purpose of this study was to determine the prevalence of medical and nonmedical use of prescription attention deficit hyperactive disorder (ADHD) stimulant medication among medical students. Materials and methods: An IRB approved 19-question web survey was sent out to all students from a Puerto Rico (PR) medical school to assess use of ADHD medication. Out of the 250 stu-dents consulted there was a response of 152 surveys. Data was cross-referenced and compared with data from other studies. Results/discussion: From the results gathered, the study's sample had a higher prevalence of use than the 15% reported in previous studies, reaching 47.4%. Among students who had used these drugs, 89.4% indicated using it without a prescription. 86.8% of all respondents used some form of stimulant or substance in order to cope with the academic workload of medical school, includ-ing coffee, energy drinks, cigarettes, and alcohol. The majority of students (60.5%) considered study techniques workshops and exercise programs to succeed academically. Conclusion: This study suggests a higher prevalence of ADHD medication use amongst the PR medical student sample compared to findings reported of US medical students, as well as a high prevalence related to nonmedical use as a means for medical students to cope with their training. The nonmedical use of stimulants in the medical school setting remains of utmost public health and clinical concern. The results of this study could help develop proper workshops and non-pharmacological techniques to help medical students cope with their workload.
MeSH term(s)	Adaptation, Psychological ; Adult ; Amphetamine-Related Disorders/epidemiology ; Central Nervous System Stimulants/administration & dosage ; Dextroamphetamine/administration & dosage ; Female ; Humans ; Male ; Methylphenidate/administration & dosage ; Prevalence ; Puerto Rico ; Students, Medical/psychology ; Students, Medical/statistics & numerical data ; Surveys and Questionnaires ; Young Adult
Chemical Substances	Central Nervous System Stimulants ; Methylphenidate (207ZZ9QZ49) ; Dextroamphetamine (TZ47U051FI)
Language	English
Publishing date	2019-10-03
Publishing country	Puerto Rico
Document type	Journal Article
ZDB-ID	639137-0
ISSN	2373-6011 ; 0738-0658
ISSN (online)	2373-6011
ISSN	0738-0658
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Article ; Online: Identification and Characterization of the V(D)J Recombination Activating Gene 1 in Long-Term Memory of Context Fear Conditioning.

Castro-Pérez, Edgardo / Soto-Soto, Emilio / Pérez-Carambot, Marizabeth / Dionisio-Santos, Dawling / Saied-Santiago, Kristian / Ortiz-Zuazaga, Humberto G / Peña de Ortiz, Sandra

Neural plasticity

2016 Volume 2016, Page(s) 1752176

Abstract: ... mice showing that the V(D)J recombination-activating gene 1 (RAG1), which encodes a factor ... in LTM, tested 24 h after training. Overall, these findings suggest that the V(D)J recombination ...

Abstract	An increasing body of evidence suggests that mechanisms related to the introduction and repair of DNA double strand breaks (DSBs) may be associated with long-term memory (LTM) processes. Previous studies from our group suggested that factors known to function in DNA recombination/repair machineries, such as DNA ligases, polymerases, and DNA endonucleases, play a role in LTM. Here we report data using C57BL/6 mice showing that the V(D)J recombination-activating gene 1 (RAG1), which encodes a factor that introduces DSBs in immunoglobulin and T-cell receptor genes, is induced in the amygdala, but not in the hippocampus, after context fear conditioning. Amygdalar induction of RAG1 mRNA, measured by real-time PCR, was not observed in context-only or shock-only controls, suggesting that the context fear conditioning response is related to associative learning processes. Furthermore, double immunofluorescence studies demonstrated the neuronal localization of RAG1 protein in amygdalar sections prepared after perfusion and fixation. In functional studies, intra-amygdalar injections of RAG1 gapmer antisense oligonucleotides, given 1 h prior to conditioning, resulted in amygdalar knockdown of RAG1 mRNA and a significant impairment in LTM, tested 24 h after training. Overall, these findings suggest that the V(D)J recombination-activating gene 1, RAG1, may play a role in LTM consolidation.
MeSH term(s)	Amygdala/metabolism ; Animals ; Association Learning/physiology ; Conditioning (Psychology)/physiology ; Electroshock ; Fear/physiology ; Genes, RAG-1 ; Hippocampus/metabolism ; Homeodomain Proteins/genetics ; Homeodomain Proteins/metabolism ; Male ; Memory, Long-Term/physiology ; Mice ; Mice, Inbred C57BL ; Neurons/metabolism
Chemical Substances	Homeodomain Proteins ; RAG-1 protein (128559-51-3)
Language	English
Publishing date	2016
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	1454938-4
ISSN	1687-5443 ; 2090-5904 ; 0792-8483
ISSN (online)	1687-5443
ISSN	2090-5904 ; 0792-8483
DOI	10.1155/2016/1752176
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Article ; Online: Confinement effects on the dynamic behavior of poly(D,L-lactic acid) upon incorporation in α-cyclodextrin.

Viciosa, M T / Alves, N M / Oliveira, T / Dionísio, M / Mano, J F

The journal of physical chemistry. B

2014 Volume 118, Issue 24, Page(s) 6972–6981

Abstract: Inclusion complexes (ICs) composed of α-cyclodextrin (α-CD) and poly(D,L-lactic acid) (PDLLA ...

Abstract	Inclusion complexes (ICs) composed of α-cyclodextrin (α-CD) and poly(D,L-lactic acid) (PDLLA), with 10/24 (IC1) and 15/46 (IC2) (% w/w) of PDLLA incorporated/initial PDLLA weight percentage, were prepared and characterized mainly by dielectric relaxation spectroscopy (DRS). Bulk PDLLA was also analyzed for comparison. DRS was revealed to be a suitable tool to distinguish the dynamical response of the PDLLA regions constrained in between α-CD channels from the fraction incorporated inside channels. While the cooperative α-process undergoes a dramatic depletion shifting to higher temperatures (∼4.5 °C) for the PDLLA interchannels portion, it is suppressed for PDLLA chains inside pores. It was demonstrated that the broad secondary relaxation of bulk PDLLA is the Johari-Goldstein process (βJG-process). The detection of its analogue in the ICs at higher frequencies, to a greater extent in IC1, is interpreted as a true confinement effect where the dimensions of the α-CD channels interfere with the length scale of the βJG-process. The limit predicted in the framework of the coupling model, where the α-relaxation transforms in the βJG-process, seems to be reached in the ICs. Furthermore, it was found that the length scale of the additional γ process only detected in the ICs is inferior to inter- or intrachannel dimensions.
MeSH term(s)	Calorimetry, Differential Scanning ; Dielectric Spectroscopy ; Lactic Acid/chemistry ; Polyesters ; Polymers/chemistry ; Temperature ; alpha-Cyclodextrins/chemistry
Chemical Substances	Polyesters ; Polymers ; alpha-Cyclodextrins ; Lactic Acid (33X04XA5AT) ; poly(lactide) (459TN2L5F5) ; alpha-cyclodextrin (Z1LH97KTRM)
Language	English
Publishing date	2014-06-19
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ISSN	1520-5207
ISSN (online)	1520-5207
DOI	10.1021/jp5045783
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