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1.
R Soc Open Sci ; 11(10): 240606, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39359460

ABSTRACT

Pupillary responses serve as sensitive indicators of cognitive processes, attentional shifts and decision-making dynamics. Our study investigates how directional uncertainty and target speed (V T) influence pupillary responses in a foveal tracking task involving the interception of a moving dot. Directional uncertainty, reflecting the unpredictability of the target's direction changes, was manipulated by altering the angular range (AR) from which random directions for the moving dot were extracted. Higher AR values were associated with reduced pupillary diameters, indicating that heightened uncertainty led to smaller pupil sizes. Additionally, an inverse U-shaped relationship between V T and pupillary responses suggested maximal diameters at intermediate speeds. Analysis of saccade-triggered responses showed a negative correlation between pupil diameter and directional uncertainty. Dynamic linear modelling revealed the influence of past successful collisions and other behavioural parameters on pupillary responses, emphasizing the intricate interaction between task variables and cognitive processing. Our results highlight the dynamic interplay between the directional uncertainty of a single moving target, V T and pupillary responses, with implications for understanding attentional mechanisms, decision-making processes and potential applications in emerging technologies.

2.
Sci Total Environ ; 941: 173671, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38825194

ABSTRACT

Polylepis trees grow at elevations above the continuous tree line (3000-5000 m a.s.l.) across the Andes. They tolerate extreme environmental conditions, making them sensitive bioindicators of global climate change. Therefore, investigating their ecohydrological role is key to understanding how the water cycle of Andean headwaters could be affected by predicted changes in environmental conditions, as well as ongoing Polylepis reforestation initiatives in the region. We estimate, for the first time, the annual water balance of a mature Polylepis forest (Polylepis reticulata) catchment (3780 m a.s.l.) located in the south Ecuadorian páramo using a unique set of field ecohydrological measurements including gross rainfall, throughfall, streamflow, and xylem sap flow in combination with the characterization of forest and soil features. We also compare the forest water balance with that of a tussock grass (Calamagrostis intermedia) catchment, the dominant páramo vegetation. Annual gross rainfall during the study period (April 2019-March 2020) was 1290.6 mm yr-1. Throughfall in the Polylepis forest represented 61.2 % of annual gross rainfall. Streamflow was the main component of the water balance of the forested site (59.6 %), while its change in soil water storage was negligible (<1 %). Forest evapotranspiration was 54.0 %, with evaporation from canopy interception (38.8 %) more than twice as high as transpiration (15.1 %). The error in the annual water balance of the Polylepis catchment was small (<15 %), providing confidence in the measurements and assumptions used to estimate its components. In comparison, streamflow and evapotranspiration at the grassland site accounted for 63.7 and 36.0 % of the water balance, respectively. Although evapotranspiration was larger in the forest catchment, its water yield was only marginally reduced (<4 %) in relation to the grassland catchment. The substantially higher soil organic matter content in the forest site (47.6 %) compared to the grassland site (31.8 %) suggests that even though Polylepis forests do not impair the hydrological function of high-Andean catchments, their presence contributes to carbon storage in the litter layer of the forest and the underlying soil. These findings provide key insights into the vegetation-water­carbon nexus in high Andean ecosystems, which can serve as a basis for future ecohydrological studies and improved management of páramo natural resources considering changes in land use and global climate.


Subject(s)
Environmental Monitoring , Forests , Ecuador , Tropical Climate , Hydrology , Climate Change , Soil/chemistry , Trees , Altitude , Water Cycle , Rain , Water
3.
Braz. j. biol ; 84: e259131, 2024. tab, graf, ilus
Article in English | VETINDEX | ID: biblio-1384083

ABSTRACT

Scolytinae species that, in high populations, can damage reducing wood production in forest crops. These beetles are monitored with traps baited with ethanol and increasing their efficiency can improve the integrated management of these insects. The objective was to evaluate the increase in the capture efficiency of Scolytinae with a semi-funnel trap model, in two experiments, one including wooden elements and other increasing the flight interception area and to correlate the numbers of these beetles collected with climatic factors. In the experiment 1, Eucalyptus urophylla S. T. Blake slats were directly attached to the collector flask and in another treatment, in addition to these slats, Cedrela sp. strips were inserted inside the bait holding hose. In the experiment 2, the insect interception area in the trap, originally 480 cm2, was expanded to 1,200 cm2 and compared with the model Pet-Santa Maria trap with an interception area of 550 cm2. Weekly collections were carried out between May 2018 and June 2019. The beetles collected were taken to the Wood Biodeterioration Laboratory of the Federal Rural University of Rio de Janeiro (UFRRJ) where they were sorted, identified at family level, counted and their number correlated with climatic factors. Statistical analyzes of the collected data were processed by the BioStat® 5.3 program. In the experiment 1 were collected 869 Scolytinae. The numbers of beetles collected per trap without modification, with E. urophylla slats and E. urophylla slats + Cedrela sp. strips were similar, 7.3 ± 3.8, 7.8 ± 6.2 and 7.7 ± 5.0 respectively. In the experiment 2 were collected 4,398 Scolytinae. Increasing the interception area of the beetles increased the efficiency of the semi-funnel trap, with 42.7 ± 20.5 Scolytinae collected compared to the original semi-funnel trap, 28.6 ± 12.6 and the Pet-Santa Maria, 20.4 ± 10.4, per trap. The number of Scolytinae did not correlate with climatic factors in the experiment 1 and it was correlated with temperature, relative humidity and wind speed, but not with precipitation, in the 2. The incorporation of E. urophylla slats or Cedrela sp. strips in the semi-funnel trap did not increase the number of beetles collected, but, the increase in the flight interception area and the temperature, relative humidity and wind speed were correlated with the number of beetles collected.


Espécies de besouros Scolytinae, em altas populações, podem danificar a madeira e reduzir a produtividade de cultivos florestais. Esses besouros são monitorados com armadilhas iscadas com etanol e o aumento da eficiência das mesmas pode melhorar o manejo integrado desses insetos. O objetivo foi avaliar o aumento da eficiência de captura de Scolytinae com armadilha modelo semifunil, em dois experimentos, um incluindo elementos de madeira e outro aumentando a área de interceptação de voo e correlacionar o número desses besouros coletados com fatores climáticos. No experimento 1, ripas de Eucalyptus urophylla S. T. Blake foram fixadas, diretamente, no frasco coletor e em outro tratamento, além dessas ripas, fitas de Cedrela sp. foram inseridas no interior da mangueira porta isca. No experimento 2, a área de interceptação de insetos na armadilha, originalmente, com 480 cm2, foi ampliada para 1200 cm2 e comparada com a armadilha modelo Pet-Santa Maria com área de interceptação de 550 cm2. Coletas semanais foram realizadas entre maio de 2018 a junho de 2019. Os insetos capturados foram levados ao Laboratório de Biodeterioração da Madeira da Universidade Federal Rural do Rio de Janeiro (UFRRJ) onde foram triados, identificados em nível de família, contados e a abundância correlacionada com fatores climáticos. As análises estatísticas dos dados coletados foram processadas pelo programa BioStat® 5.3. No experimento 1 foram coletados 869 Scolytinae. Os números de besouros coletados por armadilha sem modificação, com ripas de E. urophylla e com ripas de E. urophylla + fita de Cedrela sp. foram semelhantes, 7,3 ± 3,8; 7,8 ± 6,2 e 7,7 ± 5,0 respectivamente. No experimento 2 foram coletados 4398 Scolytinae. O aumento da área de interceptação dos besouros aumentou a eficiência da armadilha semifunil, com 42,7 ± 20,5 Scolytinae coletados por armadilha comparado a semifunil original, 28,6 ± 12,6 e a Pet-Santa Maria, 20,4 ± 10,4. O número de Scolytinae não se correlacionou com os fatores climáticos no experimento 1 e se correlacionou com a temperatura, umidade relativa e velocidade do vento, mas não com a precipitação, no 2. A incorporação de ripas de E. urophylla ou fitas de Cedrela sp. na armadilha semifunil não aumentou o número de besouros coletados, mas, o aumento da área de intercepção de voo e a temperatura, umidade relativa do ar e velocidade do vento se correlacionaram com o número de besouros coletados.


Subject(s)
Animals , Coleoptera , Pest Control/instrumentation , Agricultural Pests , Ethanol
4.
J Exp Bot ; 74(16): 4825-4846, 2023 09 02.
Article in English | MEDLINE | ID: mdl-37490359

ABSTRACT

Adequate management of N supply, plant density, row spacing, and soil cover has proved useful for increasing grain yields and/or grain yield stability of rainfed crops over the years. We review the impact of these management practices on grain yield water-related determinants: seasonal crop evapotranspiration (ET) and water use efficiency for grain production per unit of evapotranspired water during the growing season (WUEG,ET,s). We highlight a large number of conflicting results for the impact of management on ET and expose the complexity of the ET response to environmental factors. We analyse the influence of management practices on WUEG,ET,s in terms of the three main processes controlling it: (i) the proportion of transpiration in ET (T/ET), (ii) transpiration efficiency for shoot biomass production (TEB), and (iii) the harvest index. We directly relate the impact of management practices on T/ET to their effect on crop light interception and provide evidence that management practices significantly influence TEB. To optimize WUEG,ET,s, management practices should favor soil water availability during critical periods for seed set, thereby improving the harvest index. The need to improve the performance of existing crop growth models for the prediction of water-related grain yield determinants under different management practices is also discussed.


Subject(s)
Soil , Water , Water/physiology , Edible Grain , Crops, Agricultural , Seeds
5.
Ciênc. rural (Online) ; 53(12): e20220017, 2023. tab, graf
Article in English | VETINDEX | ID: biblio-1439896

ABSTRACT

Silvopastoral systems can have animal welfare and sustainability benefits because trees continually remove carbon from atmosphere, reducing greenhouse effects. Thisstudy identified the most promising fruit trees for inclusion in silvopastoral systems to dairy cattle calves. This experiment was conducted at EmbrapaAgrossilvipastoril, Brazil, between 2014 and 2018. Five silvopastoral systems with fruit trees and 'Tifton-85' grass were designed to evaluate tree growth and light environment under the canopies. Data were analyzed using SAS® and PDIFF (P < 0.10). Caja fruit trees had the greatest tree height (5.4 m) and trunk diameter (23.4 cm), while acerola fruit tree had the smallest (1.8 m and 8.3 cm, respectively). At 42 months (drought 2017), caja, cashew, and guava trees had similar heights. Guava trees had the highest light interception (89.3%), both cashew cultivars provided medium levels of shade (50 to 60% LI) and with greater constancy between the rainy and dry seasons. The systems that showed increased light interception during the drought period were those with CCP76 in 2017 and EMB51 in 2018. Higher incidences of wavelengths of the spectral composition of light occurred between the rainfall (2015) and drought (2017) periods, and greater differences in the ratio of red:far red in 2015. By 2018, there were no more differences between the rainy and dry seasons for the spectral composition of light under the tree canopies. Cashews and guava trees have adequate growth and light environment to support silvopastoral systems but Caja and acerola fruit trees showed limitations.


Sistemas silvipastoris beneficiam tanto o bem-estar animal como a sustentabilidade, pois as árvores removem o carbono da atmosfera, reduzindo o efeito estufa. O objetivo foi identificar as fruteiras mais promissoras para inclusão em sistemas silvipastoris. Este experimento foi conduzido na Embrapa Agrossilvipastoril, entre 2014 e 2018. Cinco sistemas silvipastoris com fruteiras e 'Tifton-85' foram projetados para avaliar o crescimento das árvores e o ambiente luminoso sob as copas. Os dados foram analisados com SAS® e PDIFF (P < 0,10). As cajazeiras apresentaram as maiores alturas (5,4 m) e maiores diâmetros do tronco (23,4 cm), enquanto as aceroleiras tiveram os menores (1,8 m e 8,3 cm, respectivamente). Aos 42 meses (seca de 2017), cajazeiras, cajueiros e goiabeiras apresentavam alturas semelhantes. As goiabeiras apresentaram a maior interceptação de luz (89,3%), as cultivares de cajueiro proporcionaram níveis médios de sombra (50 a 60% LI) e com maior constância entre as estações chuvosa e seca. Os sistemas que apresentaram maior interceptação de luz durante o período de seca foram aqueles com CCP76 em 2017 e EMB51 em 2018. Maiores incidências de comprimentos de onda da composição espectral da luz ocorreram entre os períodos de chuva (2015) e seca (2017) e maiores diferenças na proporção de vermelho: vermelho distante em 2015. Em 2018, não havia mais diferenças entre as estações chuvosa e seca para a composição espectral da luz sob as copas das árvores. Os cajueiros e as goiabeiras têm crescimento e ambiente luminoso adequado para suportar sistemas silvipastoris, mas as cajazeiras e aceroleiras apresentam limitações.


Subject(s)
Animals , Cattle , Animal Welfare , Malpighiaceae , Anacardium , Psidium , Fruit
6.
Biosci. j. (Online) ; 39: e39067, 2023.
Article in English | LILACS-Express | LILACS | ID: biblio-1566070

ABSTRACT

This study evaluated under grazing intensities and periods of the year: leaf anatomy of Urochloa brizantha cv. Xaraés and its correlation with morphogenetic and structural characteristics, and leaves degradation after in situ incubation. Treatments were four grazing intensities (GI) defined by the pasture residuals leaf area index (rLAI 0.8, 1.3, 1.8, and 2.3) with three replications in a completely randomized design. Cows grazed in a rotational stocking with pastures regrowth period determined by 95% light interception. Leaves showed a higher proportion of sclerenchyma (2.64%) in pastures under lower GI and in the dry season (2.42%). Pastures managed under higher GI showed lower number of expanded leaves (2.58), lower number of lives leaves (3.45), and lower leaf senescence rate (0.05 cm tiller−1 d−1). Positive correlation was observed between leaf elongation rate and adaxial epidermis and vascular tissues. rLAI 1.8 and 2.3 provided greater residues after in situ leaf incubation at times 12, 48, 72, and 96 h compared to rLAI 0.8 and 1.3. rLAI and period of the year had little influence on leaf anatomy of the Xaraés managed under 95% LI, and leaf anatomy is correlated with the morphogenetic and structural pasture characteristics. Pastures managed under lower GI show more residues after leaves incubation in rumen.

7.
Trop Anim Health Prod ; 54(6): 357, 2022 Oct 21.
Article in English | MEDLINE | ID: mdl-36269460

ABSTRACT

The objective of this study was to identify the main technologies used in the management of ruminant grazing. We developed a review protocol in which the search terms were previously tested and based on the PVO strategy to determine the guiding question (population [P]: domestic ruminants; variables [V] of interest: grazing management technologies; and outcomes [O]: intake, performance, and productivity of animals raised exclusively on pasture). The guiding question was the following: What technologies are used in the grazing management of domestic ruminants on pasture? The databases used were SCOPUS (Elsevier), SciELO Citation Index, Science Direct, and Wiley Online Library, and the search was carried out until October 15, 2021. The search identified 2683 research articles; however, only 43 were considered eligible and included due to their methodological robustness for data extraction. The most commonly used species were Lolium multiflorum and Lolium perenne (20%), Panicum maximum (18%), and Brachiaria brizantha (14%). The most widely used grazing methods were continuous grazing (53.4%) and intermittent grazing (39.5%). Among the technologies, the most widely adopted were pasture height (55.8%) and herbage allowance (11.6%). The most frequent sampling methods were the use of a ruler (37.2%) and measuring stick (13.9%) to measure the height, and clipping with a frame (18.6%) to measure herbage allowance. The animals used in the included studies were cattle (n = 1335), sheep (n = 839), and goats (n = 41). Pasture height and herbage allowance were the most widely used grazing management technologies, with the data concentrated mainly in Brazil, in studies with continuous grazing by cattle.


Subject(s)
Animal Feed , Animal Husbandry , Diet , Animals , Cattle , Animal Feed/analysis , Brachiaria , Brazil , Diet/veterinary , Lolium , Panicum , Ruminants , Sheep , Animal Husbandry/methods
8.
Plants (Basel) ; 11(8)2022 Apr 12.
Article in English | MEDLINE | ID: mdl-35448778

ABSTRACT

Absorbed energy in excess of that used by photosynthesis induces photoinhibition, which is common in water deficit conditions, resulting in reductions in stomatal conductance. In grapevines, controlled water deficit is a common field practice, but little is known about the impact of a given water shortage on the energy transduction processes at the leaf level in relation to contrasting stomatal sensitivities to drought. Here, we assessed the effect of a nearly similar water deficit condition on four grapevine varieties: Cabernet Sauvignon (CS) and Sauvignon Blanc (SB), which are stomatal sensitive, and Chardonnay (CH) and Carménère (CM), which are less stomatal sensitive, grown in 20 L pots outdoors. Plants were maintained to nearly 94% of field capacity (WW) and 83% field capacity (WD). We have assessed plant water status, photosynthesis (AN), photorespiration, AN vs. PAR, ACi curves, photochemical (qP) and non-photochemical (qN) fluorescence quenching vs. PAR, the photoprotective effectiveness of NPQ (qPd) and light interception by leaves. Photorespiration is important under WD, but to a different extent between varieties. This is related to stomatal sensitivity, maintaining a safe proportion of PSII reaction centres in an open state. Additionally, the capacity for carboxylation is affected by WD, but to a greater extent in more sensitive varieties. As for qN, in WD it saturates at 750 µmol PAR m-2s-1, irrespective of the variety, which coincides with PAR, from which qN photoprotective effectiveness declines, and qP is reduced to risky thresholds. Additionally, that same PAR intensity is intercepted by WD leaves from highly stomatal-sensitive varieties, likely due to a modification of the leaf angle in those plants. Pigments associated with qN, as well as chlorophylls, do not seem to be a relevant physiological target for acclimation.

9.
Ann Bot ; 130(3): 409-418, 2022 09 19.
Article in English | MEDLINE | ID: mdl-35325023

ABSTRACT

BACKGROUND AND AIMS: The ecohydrological significance of leaf wetting due to atmospheric water in arid and semiarid ecosystems is not well understood. In these environments, the inputs of precipitation or dew formation resulting in leaf wetting have positive effects on plant functioning. However, its impact on plant water relations may depend on the degree of leaf surface wettability. In this study we evaluated leaf wettability and other leaf traits and its effects on foliar water uptake and canopy interception in plant species of a Patagonian steppe. We also studied how leaf traits affecting wettability vary seasonally from growing to dry season. METHODS: Contact angle of a water droplet with the leaf surface, water adhesion, droplet retention angle, stomatal density, cuticular conductance, canopy interception and maximum foliar water uptake were determined in six dominant shrub species. KEY RESULTS: All species increased leaf wettability during the dry season and most species were considered highly wettable. The leaf surface had very high capacity to store and retain water. We found a negative correlation between foliar water uptake and leaf hydrophilia. CONCLUSIONS: Despite the diversity of life forms, including cushion shrubs and tall shrubs, as well as phenological variability, all species converged in similar seasonal changes in leaf traits that favour wettability. Intercepted water by crowns and the extremely high capacity of retention of droplets on leaf surfaces can have a significant impact on eco-hydrological process in water limited ecosystems where most of water sources during the growing and the dry season may be small rainfall events or dew, which do not always increase soil water availability.


Subject(s)
Groundwater , Water , Ecosystem , Plant Leaves , Plants , Soil , Wettability
10.
Ortho Sci., Orthod. sci. pract ; 15(59): 30-39, 2022. tab, ilus
Article in Portuguese | BBO - Dentistry | ID: biblio-1401074

ABSTRACT

A má oclusão Classe II, Divisão 1, é comumente encontrada na clínica ortodôntica e normalmente está relacionada ao retrognatismo mandibular. Este trabalho consiste em um relato de caso de um paciente Classe II, Divisão 1, com 7,2 anos de idade, na fase de dentição mista, com projeção exagerada de incisivos superiores e retrognatismo mandibular. O tratamento realizado foi a utilização do aparelho ortopédico funcional de Klammt. Após 24 meses, o paciente apresentou melhora na relação dos molares e caninos, redução do overjet e do overbite e melhora na harmonia facial. Concluiu-se que o AOF de Klammt mostrou-se eficiente e eficaz na interceptação da má oclusão Classe II, Divisão 1, de um paciente em crescimento, com melhora esquelética, dentária e do perfil facial, além de solucionar a queixa principal de bullying. No follow-up de 13 meses, observou-se melhora nas relações oclusais de molares e caninos em Classe I.(AU)


Abstract Class II, Division 1, malocclusion is a common malocclusion in the orthodontic clinic and is usually related to mandibular retrognathism. This paper consists of a case report of a Class II, Division 1 patient, 7.2 years old, in the mixed dentition phase, with exaggerated projection of maxillary incisors and mandibular retrognathism. The treatment performed was the use of the Klammt functional orthopedic appliance. After 24 months, the patient showed improvement in molar and canine relationship, reduction of overjet and overbite, and improvement in facial harmony. It is concluded that Klammt's AOF proved to be efficient and effective in interception of Class II, Division 1 malocclusion of a growing patient, with skeletal, dental, and facial profile improvement and solving the patient's main complaint of bullying. In the 13-month follow-up, there was an improvement in the occlusal relationships of molars and canines in Class I. (AU)


Subject(s)
Humans , Male , Child , Retrognathia , Malocclusion, Angle Class II , Molar
11.
Sci. agric ; 79(02): 1-7, 2022. tab
Article in English | VETINDEX | ID: biblio-1498035

ABSTRACT

There is limited information regarding both nitrogen (N) and energy partitioning of dairy cows grazing well–managed tropical pastures. The objective of this study was to investigate the N and energy partitioning of mid–lactation dairy cows on rotationally grazed elephant grass using two pre–grazing targets: 95 % or maximum canopy light interception (LI95% or LIMax) during regrowth. The study used 26 Holstein × Jersey dairy cows arranged in a randomized complete block design with three 40–day periods of sampling. Grazing at LI95% increased organic matter and crude protein intake by 20 % (p ≤ 0.05) which resulted in a 9 % increase in fat corrected milk yield (p ≤ 0.05) relative to LIMax. Cows grazing at LI95% had greater concentration of total volatile fatty acids, butyrate and valerate (p ≤ 0.05), and smaller acetate (p ≤ 0.05) than those grazing at LIMax. Intake of net energy for lactation (NEL) and NEL secreted in milk were greater (p ≤ 0.05), while partitioning of NEL towards maintenance tended to be greater (p = 0.07) for cows grazing at LI95% than those grazing at LIMax. Milk urea nitrogen and both urine and fecal N excretion were greater for cows grazing at LI95% (p ≤ 0.05), but N excretion intensity was lower than in cows grazing at LIMax (p ≤ 0.05). Strategic grazing management using the LI95% pre–grazing target increases N losses through both urine and feces; however, it reduces N excretion intensity of dairy cows by 9 %.


Subject(s)
Female , Animals , Cattle , Flatulence/veterinary , Nitrogen , Pennisetum
12.
Sci. agric. ; 79(2)2022.
Article in English | VETINDEX | ID: vti-762550

ABSTRACT

ABSTRACT: There is limited information regarding both nitrogen (N) and energy partitioning of dairy cows grazing wellmanaged tropical pastures. The objective of this study was to investigate the N and energy partitioning of midlactation dairy cows on rotationally grazed elephant grass using two pregrazing targets: 95 % or maximum canopy light interception (LI95% or LIMax) during regrowth. The study used 26 Holstein × Jersey dairy cows arranged in a randomized complete block design with three 40day periods of sampling. Grazing at LI95% increased organic matter and crude protein intake by 20 % (p 0.05) which resulted in a 9 % increase in fat corrected milk yield (p 0.05) relative to LIMax. Cows grazing at LI95% had greater concentration of total volatile fatty acids, butyrate and valerate (p 0.05), and smaller acetate (p 0.05) than those grazing at LIMax. Intake of net energy for lactation (NEL) and NEL secreted in milk were greater (p 0.05), while partitioning of NEL towards maintenance tended to be greater (p = 0.07) for cows grazing at LI95% than those grazing at LIMax. Milk urea nitrogen and both urine and fecal N excretion were greater for cows grazing at LI95% (p 0.05), but N excretion intensity was lower than in cows grazing at LIMax (p 0.05). Strategic grazing management using the LI95% pregrazing target increases N losses through both urine and feces; however, it reduces N excretion intensity of dairy cows by 9 %.

13.
Sci. agric ; 79(2): e20200251, 2022. tab
Article in English | VETINDEX | ID: biblio-1290176

ABSTRACT

There is limited information regarding both nitrogen (N) and energy partitioning of dairy cows grazing well­managed tropical pastures. The objective of this study was to investigate the N and energy partitioning of mid­lactation dairy cows on rotationally grazed elephant grass using two pre­grazing targets: 95 % or maximum canopy light interception (LI95% or LIMax) during regrowth. The study used 26 Holstein × Jersey dairy cows arranged in a randomized complete block design with three 40­day periods of sampling. Grazing at LI95% increased organic matter and crude protein intake by 20 % (p ≤ 0.05) which resulted in a 9 % increase in fat corrected milk yield (p ≤ 0.05) relative to LIMax. Cows grazing at LI95% had greater concentration of total volatile fatty acids, butyrate and valerate (p ≤ 0.05), and smaller acetate (p ≤ 0.05) than those grazing at LIMax. Intake of net energy for lactation (NEL) and NEL secreted in milk were greater (p ≤ 0.05), while partitioning of NEL towards maintenance tended to be greater (p = 0.07) for cows grazing at LI95% than those grazing at LIMax. Milk urea nitrogen and both urine and fecal N excretion were greater for cows grazing at LI95% (p ≤ 0.05), but N excretion intensity was lower than in cows grazing at LIMax (p ≤ 0.05). Strategic grazing management using the LI95% pre­grazing target increases N losses through both urine and feces; however, it reduces N excretion intensity of dairy cows by 9 %.


Subject(s)
Animals , Female , Pregnancy , Cattle , Cattle/metabolism , Pasture/methods , Nitrogen/analysis , Pennisetum
14.
Environ Monit Assess ; 193(12): 789, 2021 Nov 10.
Article in English | MEDLINE | ID: mdl-34757510

ABSTRACT

Rainfall is generally partitioned into throughfall, stemflow, and interception in ecosystems. Stemflow variability can affect the hydrology, ecology, and soil chemistry patterns. However, the influence of canopy structure and rainfall characteristics on stemflow production in sugarcane plantations which are important for renewable energy production remain poorly understood. By using funnels attached to the sugarcane stems, the present study determined the stemflow amount during the period of sugarcane growth and its relationship with plant development. Approximately, 14% of gross rainfall reached the soil as stemflow, and the funneling ratios was 60. In general, it was observed a positive relationship between stemflow rates with both leaf area index and plant height. This was attributed to an increasing number of acute branching angles of the sugarcane leaves as well as high stem tillering and density. However, at the end of growth cycle, stemflow rate was lower than in previous periods which can be attributed to changes in sugarcane canopy such as stems inclination and lodging, reducing the effectiveness of water conveyance along the stem. Our study showed the need to include stemflow to better understand the hydrology of sugarcane plantations.


Subject(s)
Rain , Saccharum , Ecosystem , Environmental Monitoring , Soil , Trees
15.
Clin Lung Cancer ; 22(6): 570-578, 2021 11.
Article in English | MEDLINE | ID: mdl-34257020

ABSTRACT

BACKGROUND: One challenge in high-quality lung cancer screening (LCS) is maintaining adherence with annual and short-interval follow-up screens among high-risk individuals who have undergone baseline low-dose CT (LDCT). This study aimed to characterize attitudes and beliefs toward lung cancer and LCS and to identify factors associated with LCS adherence. METHODS: We administered a questionnaire to 269 LCS participants to assess attitudes and beliefs toward lung cancer and LCS. Clinical data including sociodemographics and screening adherence were obtained from the LCS Program Registry. RESULTS: African-American individuals had significantly greater lung cancer worries compared with Whites (6.10 vs. 4.66, P < .001). In making the decision to undergo LCS, African-American participants described screening convenience and cost as very important factors significantly more frequently than Whites (60% vs. 26.8%, P< .001 and 58.4% vs. 37.8%, P = .001; respectively). African-American individuals with greater than high school education had significantly higher odds of LCS adherence (aOR 2.55; 95% CI, 1.14-5.60) than Whites with less than high school education. Participants who described screening convenience and cost as "very important" had significantly lower odds of completing screening follow-up after adjusting for demographic and other factors (aOR 0.56; 95% CI, 0.33-0.97 and aOR 0.54; 95% CI, 0.33-0.91, respectively). CONCLUSION: Racial differences in beliefs about lung cancer and LCS exist among African-American and White individuals enrolled in an LCS program. Cost, convenience, and low educational attainment may be barriers to LCS adherence, specifically among African-American individuals. IMPACT: More research is needed on how barriers can be overcome to improve LCS adherence.


Subject(s)
Early Detection of Cancer , Healthcare Disparities , Lung Neoplasms/diagnosis , Mass Screening , Race Factors , Aged , Female , Humans , Male , Middle Aged , Patient Acceptance of Health Care , Surveys and Questionnaires
16.
rev. udca actual. divulg. cient ; 24(1): e1312, ene.-jun. 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1290418

ABSTRACT

ABSTRACT Banana is after apple, the most consumed fruit in the world for its nutritional contribution. Given its importance, it is necessary to advance in the development of agronomic management strategies that contribute to increase productivity and offer alternatives to regulate the consequences derived from the seasonality of production in the Urabá area (Colombia). For this, the clone Williams (Musa AAA Simmonds), at different planting densities (2000, 2500, 3000 and 3500 plants ha-1), different population arrangements (triangle, rectangle and double furrow), compared with a relative control (1700 plants ha-1 in triangle) was evaluated. The design used was randomized complete blocks in factorial arrangement of 4 x 3 + 1 (densities x arrays + control). The variables height and perimeter of the pseudostem, number of leaves from planting to harvest, leaf area index (IAF), light extinction coefficient, number of suckers and developmental stages (days elapsed after flowering and harvest) were determined. An analysis of general variance was carried out and another one excluding the control. The Tukey test (P <0.05) was applied to the qualitative variables and contrasts of orthogonal polynomials were made to test the linear and quadratic effects of the population density factor. The results indicated that the high planting densities and the population arrangements had a negative effect on the perimeter of the pseudostem and the height of the main sucker, favored the LAI, influenced the extinction coefficient, but did not affect the development of the plants.


RESUMEN El banano es después de la manzana la fruta más consumida en el mundo, por su aporte nutricional. Dada su importancia, se requiere avanzar en el desarrollo de estrategias de manejo agronómico, que contribuyan a incrementar la productividad y ofrezcan alternativas para regular las consecuencias derivadas de la estacionalidad de la producción, en la zona del Urabá (Colombia). Para ello, se evaluaron en el clon Williams (Musa AAA Simmonds), diferentes densidades de plantación (2.000, 2.500, 3.000 y 3.500 plantas ha-1), distintos arreglos poblacionales (triángulo, rectángulo y doble surco) y un testigo relativo (1.700 plantas ha-1 en triángulo). El diseño utilizado fue de bloques completos al azar en arreglo factorial, de 4 x 3 + 1 (densidades x arreglos + testigo). Se determinaron la altura y perímetro del pseudotallo, el número de hojas de siembra a cosecha, el índice de área foliar (IAF), el coeficiente de extinción de luz, el número de hijos y fases de desarrollo: días transcurridos a floración y cosecha. Se realizó un análisis de varianza general y otro excluyendo el testigo. Se aplicó la prueba de Tukey (P<0,05) a las variables cualitativas y se hicieron contrastes de polinomios ortogonales, para probar los efectos lineal y cuadrático del factor densidad de población. Los resultados indicaron que las altas densidades de plantación y los arreglos poblacionales tuvieron un efecto negativo sobre el perímetro del pseudotallo y la altura del hijo a parición, favorecieron el IAF, influyeron en el coeficiente de extinción, pero no afectaron el desarrollo de las plantas.

17.
Ortho Sci., Orthod. sci. pract ; 14(54): 62-72, 2021. tab, ilus
Article in Portuguese | BBO - Dentistry | ID: biblio-1283400

ABSTRACT

Resumo O tratamento ortodôntico da maloclusão Classe II, divisão 1 em uma ou duas fases ainda é controverso na Ortodontia contemporânea. O presente relato de caso clínico ilustra o tratamento ortodôntico de um paciente de 6 anos de idade com queixa estética e bullying em relação ao sorriso, apresentando Classe II esquelética, maloclusão Classe II, divisão 1 de Angle, overjet com labioversão exagerada dos incisivos superiores, overbite exagerado com os incisivos inferiores tocando a mucosa do palato, ausência de selamento labial e perfil inferior da face côncavo. Na Fase I, realizou-se a expansão rápida da maxila com aparelho expansor tipo Hyrax associado ao aparelho ortopédico funcional fixo tipo Herbst, durante 11 meses. Na Fase II, utilizou-se o aparelho ortodôntico fixo associado a elásticos intermaxilares por 13 meses. O tratamento em duas fases da maloclusão Classe II, divisão 1, após 24 meses, mostrou-se eficaz em estabelecer resultados oclusais e funcionais adequados e melhora na estética do terço inferior da face (AU)


Abstract Orthodontic treatment of Class II, division 1 malocclusion in one or two phases is still controversial in contemporary Orthodontics. The present clinical case presents the orthodontic treatment of a 6-year-old patient with aesthetic complaint regarding the smile and bullying, presenting skeletal Class II, Class II malocclusion, Angle division 1, overjet with exaggerated protrusion of the maxillary incisors, exaggerated overbite with the lower incisors touching the palatal mucosa, absence of lip sealing and concave inferior face profile. In Phase I, rapid maxillary expansion was performed with Hyrax-type expander together with the Herbst fixed functional orthopedic device for 11 months. In Phase II, the fixed orthodontic appliance associated with intermaxillary elastics was used for 13 months. The two-phase treatment of Class II malocclusion, division 1 showed to be effective after 24 months, establishing adequate occlusal and functional results and improving the aesthetics of the lower third of the face.(AU)


Subject(s)
Child , Orthodontics , Orthodontic Appliances, Functional , Malocclusion, Angle Class II
18.
Rev. bras. zootec ; 50: e20200225, 2021. tab, graf
Article in English | VETINDEX | ID: biblio-1443285

ABSTRACT

This work evaluated the productive and structural characteristics of the BRS Zuri and BRS Quênia cultivars under rotational stocking management. The evaluations were divided into five periods according to rainfall regime (high, medium, and low rainfall) during 16 months of the years 2016-2018. Pastures were grazed when canopies intercepted 95% of incident light to stubbles corresponding to 50% of the pre-grazing height. The pre- and post-grazing heights varied as a function of cultivar, with higher values for BRS Zuri (89 and 49 cm) than for BRS Quênia (78 and 45 cm). No differences in canopy lowering percentage, forage mass, and stem and dead material dry masses between cultivars were observed, with averages of 41.3%, 5,856, 1,835, and 841 kg ha−1, respectively. The post-grazing canopy height was lower in the second year, which resulted in higher values of canopy lowering percentage (51%). The highest value for leaf:stem ratio for both cultivars was observed in the high rainfall period of the second year. Higher average tiller population density was observed for BRS Quênia (477 tillers m−2) than for BRS Zuri (260 tillers m−2) for all the rainfall periods. Forage bulk density was similar between cultivars and varied according to the periods evaluated, with the highest value observed during the dry period of the year. Forage mass, as well as its component fractions, did not vary between cultivars, but was influenced by the studied periods. The cultivars showed high leaf mass in the pre-grazing forage mass with an average value of 3,174 kg ha−1. The cultivars are similar in morphological composition and offer high yield potential when managed under a rotational grazing system.


Subject(s)
Pasture , Poaceae , 24444
19.
Biosci. j. (Online) ; 36(6): 2142-2152, 01-11-2020. graf, tab
Article in English | LILACS | ID: biblio-1148256

ABSTRACT

The objective of this study was to evaluate the morphogenetic traits and chemical composition of Tanzania grass using a fixed rest period or according to light interception at 95%. The treatments consisted of evaluations of two Tanzania-grass pasture-management strategies: (1) LI95 - animals entered the paddocks when the pasture reached 95% of light interception (LI), with three days of paddock occupation; and (2) FR - the pasture was managed with a defoliation interval (DI) of 30 days, and three days of paddock occupation. The experimental area consisted of 4 ha, with 22 paddocks per treatments. Ten recently-calved cows were used per treatment in year 1, and eight cows were used per treatment in year 2. Sward height, forage mass, and morphological components and their chemical composition were evaluated. The management strategies used on the Tanzania grass pasture did not affect pasture mass or height in the pre- and post-grazing conditions, or the proportion of stems. However, the proportion of leaves was greater in the paddocks with 95% light interception. The crude protein content was higher in the paddocks with 95% light interception; the other nutrients were not affected. In conclusion, management adopting 95% light interception does not influence morphogenetic traits. Nevertheless, it promotes an increase in the crude protein content of grasses.


O objetivo deste trabalho foi avaliar as características morfogênicas e a composição química do capim-tanzânia, utilizando um período de descanso fixo ou de acordo com a interceptação luminosa a 95%. Os tratamentos consistiram de avaliações de duas estratégias de manejo de pastagem de capim Tanzânia: (1) LI95 - animais entraram nos piquetes quando o pasto atingiu 95% de interceptação luminosa (LI), com três dias de ocupação do piquete; e (2) FR - a pastagem foi manejada com um intervalo de desfolhamento (DI) de 30 dias e três dias de ocupação do piquete. A área experimental consistiu de 4 ha, com 22 piquetes por tratamento. Dez vacas recém-paridas foram utilizadas por tratamento no ano 1, e oito vacas foram utilizadas por tratamento no ano 2. A altura do pasto, a massa de forragem e os componentes morfológicos e sua composição química foram avaliados. As estratégias de manejo utilizadas na pastagem de capim-Tanzânia não afetaram a massa ou a altura do pasto nas condições pré e pós-pastejo, ou a proporção de hastes. No entanto, a proporção de folhas foi maior nos piquetes com 95% de interceptação de luz. O teor de proteína bruta foi maior nos piquetes com 95% de interceptação de luz; os outros nutrientes não foram afetados. Em conclusão, o manejo adotando 95% de interceptação de luz não influencia as características morfogenéticas. No entanto, promove um aumento no teor de proteína bruta das gramíneas


Subject(s)
Pasture , Panicum
20.
Ortho Sci., Orthod. sci. pract ; 13(51): 66-74, 2020. ilus, tab
Article in Portuguese | BBO - Dentistry | ID: biblio-1128531

ABSTRACT

As má oclusões de Classe II, Divisão 1 são um desafio comum em Ortodontia, e há controvérsia entre a interceptação em idade precoce ou a realização de tratamento corretivo na adolescência. O objetivo deste estudo é apresentar o relato de caso com Classe I esquelética, má oclusão de Classe II, Divisão 1, sobressaliência 9,0 mm, sobremordida exagerada com incisivos superiores cobrindo totalmente os incisivos inferiores. Preconizou-se o ativador aberto elástico de Klammt com um alongamento vertical lingual na região posterior por 16 meses. Os resultados foram a redução da sobressaliência e da sobremordida devido a uma resposta mandibular verdadeira. A manutenção do posicionamento mandibular foi observada no exame de acompanhamento sem o uso de qualquer aparelho após 4 anos e 11 anos meses (AU)


The Class II, Division 1 malocclusions are a common challenge in orthodontics, and there is controversy between interception at an early age or performing single-stage treatment in adolescence. The aim of this study is to present a case report of a skeletal Class I, Class II, Division 1 malocclusion, overjet 9,0 mm, overbite with maxillary incisors totally covering the lower incisors. The interceptive orthodontics was performed with the aid of Klammt's elastic open activator for 16 months. The results were reduction of overjet and overbite due to a true mandibular response. The maintenance of a forward positioning of the mandible was observed after 4 years and 11 months in the follow-up examination without the use of any type of appliance. (AU)


Subject(s)
Humans , Male , Child , Overbite , Incisor , Malocclusion, Angle Class II
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