Índice de vegetação por diferença normalizada obtido por sensor remoto de superfície para caracterização do ciclo de videiras no Rio Grande do Sul, Brasil

The normalized difference vegetation index (NDVI) obtained by remote sensing is widely used to monitor annual crops but few studies have investigated its use in perennial fruit crops. The aim of this study was to determine the temporal NDVI profile during grapevine cycle in vineyards established in horizontal training systems. NDVI data were obtained by the ground-based remote sensing Greenseeker in Chardonnay and Cabernet Sauvignon vineyards located in the Serra Gaúcha region, Rio Grande do Sul, Brazil, from September to June in the 2014/2015 and 2015/2016 vegetative seasons. The grapevine canopies were managed in horizontal training systems (T-trellis and Y-trellis). The results indicated that the temporal NDVI values varied during the grapevine cycle (0.33 to 0.85), reflecting the changing in vigor and biomass accumulation that resulted from the phenological stages and management practices. The temporal NDVI profiles were similar to both horizontal training systems. The NDVI values were higher throughout the cycle for Cabernet Sauvignon compared to Chardonnay indicating Cabernet Sauvignon as the cultivar with greater vegetative vigor. The NDVI obtained by ground-based remote sensing is a fast and non-destructive tool to monitor and characterize the canopy in real time, compiling into a single data several parameters related to vine development, like meteorological conditions and management practices that are difficult to be quantified together.O índice de vegetação por diferença normalizada (NDVI), obtido por sensoriamento remoto, tem sido amplamente empregado no monitoramento de culturas agrícolas produtoras de grãos, porém poucos são os estudos em fruticultura. O objetivo deste trabalho foi caracterizar a evolução temporal do NDVI obtido por sensor remoto de superfície ao longo do ciclo de videiras em sistemas horizontais de condução do dossel vegetativo. Dados de NDVI foram obtidos com sensor remoto Greenseeker em vinhedos na região da Serra Gaúcha, Rio Grande do Sul, Brasil, de setembro a junho nas safras 2014/2015 e 2015/2016. Os vinhedos das cultivares Chardonnay e Cabernet Sauvignon eram conduzidos em sistema horizontal (latada e lira). Os resultados indicaram que houve variabilidade temporal do NDVI ao longo do ciclo (de 0,33 a 0,85), a qual refletiu as alterações no acúmulo de biomassa e vigor vegetativo decorrentes das principais etapas fenológicas e práticas de manejo. A evolução temporal do NDVI foi semelhante nos sistemas latada e lira, ambos caracterizados pela condução horizontal do dossel vegetativo. Os valores de NDVI para ‘Cabernet Sauvignon’ foram superiores aos de ‘Chardonnay’ ao longo do ciclo, independe da safra avaliada e do sistema de condução, indicando ‘Cabernet Sauvignon’ como a cultivar de maior vigor vegetativo. O NDVI, obtido por sensor remoto de superfície, é uma forma rápida e não destrutiva de monitoramento e caracterização do dossel vegetativo em tempo real, compilando em uma única informação o desenvolvimento da videira, o qual é resultado de diversos fatores, edafo-climáticos e de manejo, dificilmente quantificados conjuntamente

Surgery scheduling heuristic considering OR downstream and upstream facilities and resources

Background: Surgical theater (ST) operations planning is a key subject in the healthcare management literature, particularly the scheduling of procedures in operating rooms (ORs). The OR scheduling problem is usually approached using mathematical modeling and made available to ST managers through dedicated software. Regardless of the large body of knowledge on the subject, OR scheduling models rarely consider the integration of OR downstream and upstream facilities and resources or validate their propositions in real life, rather using simulated scenarios. We propose a heuristic to sequence surgeries that considers both upstream and downstream resources required to perform them, such as surgical kits, post anesthesia care unit (PACU) beds, and surgical teams (surgeons, nurses and anesthetists). Methods: Using hybrid flow shop (HFS) techniques and the break-in-moment (BIM) concept, the goal is to find a sequence that maximizes the number of procedures assigned to the ORs while minimizing the variance of intervals between surgeries’ completions, smoothing the demand for downstream resources such as PACU beds and OR sanitizing teams. There are five steps to the proposed heuristic: listing of priorities, local scheduling, global scheduling, feasibility check and identification of best scheduling. Results: Our propositions were validated in a high complexity tertiary University hospital in two ways: first, applying the heuristic to historical data from five typical ST days and comparing the performance of our proposed sequences to the ones actually implemented; second, pilot testing the heuristic during ten days in the ORs, allowing a full rotation of surgical specialties. Results displayed an average increase of 37.2% in OR occupancy, allowing an average increase of 4.5 in the number of surgeries performed daily, and reducing the variance of intervals between surgeries’ completions by 55.5%. A more uniform distribution of patients’ arrivals at the PACU was also observed. Conclusions: Our proposed heuristic is particularly useful to plan the operation of STs in which resources are constrained, a situation that is common in hospital from developing countries. Our propositions were validated through a pilot implementation in a large hospital, contributing to the scarce literature on actual OR scheduling implementation

Influência das gemas laterais sobre a brotação da gema apical em ramos de macieira

A influência da dominância apical é amplamente estudada em frutíferas, porém trabalhos que evidenciem o efeito contrário são desconhecidos. Objetivou-se avaliar a influência das gemas laterais (GL) sobre a gema apical (GA) em ramos de macieira. Amostraram-se brindilas, de 20-25 cm da cv. Castel Gala, em maio/2010 e junho/2011, em Papanduva-SC. Os tratamentos foram: i) 2010 -  I: estaca intacta;  A: remoção alternada de 50% das GL ao longo do ramo; SI: remoção das GL inferiores do ramo (50%); SS: remoção das GL superiores do ramo (50%); SL: remoção de todas as GL do ramo e SA: remoção da GA do ramo; ii) 2011 - I: estaca intacta; SS: remoção das GL superiores do ramo (50%); FSLS: estaca intacta com ferimento abaixo das GL superiores. As estacas foram submetidas à 3ºC por 168, 336 e 504 horas de frio (HF), em 2010, e 456 HF, em 2011, sendo posteriormente transferidas para 25°C, para avaliação da brotação. Avaliaram-se os dados quanto aos parâmetros brotação máxima, precocidade e uniformidade. O aumento de HF elevou a quantidade de GA brotadas, devido à superação da dormência. As GL foram fortemente afetadas pela dominância apical, independentemente do período de frio. Os tratamentos com presença de GL superiores proporcionaram menor percentual de brotação máxima e menor precocidade e uniformidade de brotação das GA se comparados aos demais tratamentos. As GA sofrem influência das GL, especialmente das situadas próximas à extremidade superior dos ramos, sendo uma informação relevante do ponto de vista fisiológico e fitotécnico, considerando que a produção se concentra neste grupo de gemas.La influencia del dominio apical se estudia ampliamente en los árboles frutales, pero se desconocen los estudios que muestran el efecto contrario. El objetivo fue evaluar la influencia de las yemas laterales (GL) en la yema apical (AG) en las ramas de manzana. Tostadas, 20-25 cm de cv. Castel Gala, en mayo / 2010 y junio /2011, en Papanduva-SC. Los tratamientos fueron: i) 2010 - I: estaca intacta; A: eliminación alternativa del 50% de GL a lo largo de la rama; SI: eliminación de GL inferior de la rama (50%); SS: eliminación de GL superior de la rama (50%); SL: eliminación de todos los GL de la sucursal y SA: eliminación de GA de la sucursal; ii) 2011 - I: participación intacta; SS: eliminación de GL superior de la rama (50%); FSLS: estaca intacta con la herida debajo del GL superior. Los esquejes se sometieron a 3ºC durante 168, 336 y 504 horas de frío (HF), en 2010, y 456 HF, en 2011, y luego se transfirieron a 25 ° C, para la evaluación de los brotes. Los datos fueron evaluados para la brotación máxima, precocidad y parámetros de uniformidad. El aumento de HF aumentó la cantidad de GA germinada, debido a la superación de la latencia. GL fueron fuertemente afectados por el dominio apical, independientemente del período de frío. Los tratamientos con la presencia de GL superior proporcionaron un menor porcentaje de brotación máxima y menor brotación temprana y uniformidad de brotación GA en comparación con otros tratamientos. Los GA están influenciados por GL, especialmente aquellos ubicados cerca de la extremidad superior de las ramas, que es información relevante desde un punto de vista fisiológico y fitotécnico, considerando que la producción se concentra en este grupo de brotes.The influence of apical dominance is widely studied in fruit trees, but works that show the opposite effect are unknown. The objective was to evaluate the influence of lateral buds (LB) on the apical bud (AB) on apple twigs. Were sampled twigs, 20-25 cm of cv. Castel Gala in May/2010 and June/2011, in Papanduva-SC. The treatments were: i) 2010 - I: intact twig; A: removal alternating of 50% LB along the twig; SI: LB lower removal of twig (50%); SS: LB upper removal of twig (50%); SL: removal all LB of twig and SA: removal AB of twig; ii) 2011 - I: intact twig; SS: LB upper removal of twig (50%); FSLS: intact twig with injury below the LB upper. The twigs were submitted to 3ºC per 168, 336 and 504 chilling hours (CH), in 2010, and 456 CH, in 2011 and later transferred to 25ºC, for budburst evaluation. Budburst data were evaluated through maximum budburst, precocity and uniformity. The increase of HF increased the amount of AB sprouted due to overcome dormancy. The LB were strongly affected by apical dominance, regardless of the cold period. The treatments with LB upper presence provided lower percentage of maximum budburst and lower precocity and uniformity of budburst of AB compared to the other treatments. The AB is influenced by LB, especially those located near the extremity upper of twigs, one relevant information in physiological and phytotechnical aspects, considering that production is concentrated in this group of buds

Man vs. machine : predicting hospital bed demand

Background: The recent literature reports promising results from using intelligent systems to support decision making in healthcare operations. Using these systems may lead to improved diagnostic and treatment protocols and to predict hospital bed demand. Predicting hospital bed demand in emergency department (ED) attendances could help resource allocation and reduce pressure on busy hospitals. However, there is still limited knowledge on whether intelligent systems can operate as fully autonomous, user-independent systems. Objective: Compare the performance of a computer-based algorithm and humans in predicting hospital bed demand (admissions and discharges) based on the initial SOAP (Subjective, Objective, Assessment, Plan) records of the ED. Methods: This was a retrospective cohort study that compared the performance of humans and machines in predicting hospital bed demand from an ED. It considered electronic medical records (EMR) of 9030 patients (230 used as a testing set, and hence evaluated both by humans and by an algorithm, and 8800 used as a training set exclusively by the algorithm) who visited the ED of a tertiary care and teaching public hospital located in Porto Alegre, Brazil between January and December 2014. The machine role was played by Support Vector Machine Classifier and the human prediction was performed by four ED physicians. Predictions were compared in terms of sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUROC). Results: All graders achieved similar accuracies. The accuracy by AUROC for the testing set was 0.82 [95% confidence interval (CI) of 0.77–0.87], 0.80 (95% CI: 0.75–0.85), 0.76 (95% CI: 0.71–0.81) for novice physicians, machine, experienced physicians, respectively. Processing time per test EMR was 0.00812±0.0009 seconds. In contrast, novice physicians took on average 156.80 seconds per test EMR, while experienced physicians took on average 56.40 seconds per test EMR. Conclusions: Our data indicated that the system could predict patient admission or discharge states with 80% accuracy, which was similar the performance of novice and experienced physicians. These results suggested that the algorithm could operate as an autonomous and independent system to complete this task

Dormência de gemas em macieira após flutuações térmicas

The objective of this work was to evaluate the effect of heat waves on the evolution of bud dormancy, in apple trees with contrasting chilling requirements. Twigs of 'Castel Gala' and 'Royal Gala' were collected in orchards in Papanduva, state of Santa Catarina, Brazil, and were exposed to constant (3°C) or alternating (3 and 15°C for 12/12 hours) temperature, combined with zero, one or two days a week at 25°C. Two additional treatments were evaluated: constant temperature (3°C), with a heat wave of seven days at 25°C, in the beginning or in the middle of the experimental period. Periodically, part of the twigs was transferred to 25°C for daily budburst evaluation of apical and lateral buds. Endodormancy (dormancy induced by cold) was overcome with less than 330 chilling hours (CH) of constant cold in 'Castel Gala' and less than 618 CH in 'Royal Gala'. A daily 15°C‑temperature cycle did not affect the endodormancy process. Heat waves during endodormancy resulted in an increased CH to achieve bud requirements. The negative effect of high temperature depended on the lasting of this condition. Chilling was partly cancelled during dormancy when the heat wave lasted 36 continuous hours or more. Therefore, budburst prediction models need adjustments, mainly for regions with mild and irregular winters, such as those of Southern Brazil.O objetivo deste trabalho foi avaliar o efeito de ondas de calor sobre a evolução da dormência de gemas de macieiras com necessidades contrastantes de frio hibernal. Brindilas de macieiras 'Castel Gala' e 'Royal Gala' foram coletadas de pomares em Papanduva, SC, e expostas à temperatura constante (3°C) ou alternada (3 e 15°C, por 12/12 horas), combinadas com zero, um ou dois dias por semana a 25°C. Dois outros tratamentos foram avaliados: temperatura constante (3°C), com onda de calor de sete dias a 25°C, no início ou no meio do período experimental. Periodicamente, parte das brindilas era transferida para 25°C, para avaliação da brotação das gemas apicais e laterais. A endodormência (dormência induzida pelo frio) foi superada com menos de 330 horas de resfriamento (HF) constante em 'Castel Gala' e menos de 618 HF em 'Royal Gala'. Um ciclo diário de temperatura a 15°C não afetou o processo de endodormência. Ondas de calor de 25°C durante a endodormência resultaram em aumento de HF para atender à necessidade das gemas. O efeito negativo da alta temperatura dependeu da duração desta condição. O resfriamento foi parcialmente anulado durante a dormência, quando a onda de calor durou 36 horas contínuas ou mais. Portanto, os modelos de predição da brotação necessitam de ajustes, principalmente para regiões com invernos amenos e irregulares, como os do Sul do Brasil