Higher Sap Research Articles

Defining Postinduction Hemodynamic Instability With an Automated Classification Model.

Postinduction hypotension (PIH) may be associated with increased morbidity and mortality. In earlier studies, the definition of PIH is solely based on different absolute or relative thresholds. However, the time-course (eg, how fast blood pressure drops during induction) is rarely incorporated, whereas it might represent the hemodynamic instability of a patient. We propose a comprehensive model to distinguish hemodynamically unstable from stable patients by combining blood pressure thresholds with the magnitude and speed of decline. This prospective study included 375 adult elective noncardiac surgery patients. Noninvasive blood pressure was continuously measured between 5 minutes before up to 15 minutes after the first induction agent had been administered. An expert panel rated whether the patient experienced clinically relevant hemodynamic instability or not. Interrater correlation coefficient and intraclass correlation were computed to check for consistency between experts. Next, an automated classification model for clinically relevant hemodynamic instability was developed using mean, maximum, minimum systolic, mean, diastolic arterial blood pressure (SAP, MAP, and DAP, respectively) and their corresponding time course of decline. The model was trained and tested based on the hemodynamic instability labels provided by the experts. In total 78 patients were classified as having experienced hemodynamic instability and 279 as not. The hemodynamically unstable patients were significantly older (7 years, 95% confidence interval (CI), 4-11, P < .001), with a higher prevalence of chronic obstructive pulmonary disease (COPD) (3% higher, 95% CI, 1-8, P = .036). Before induction, hemodynamically unstable patients had a higher SAP (median (first-third quartile): 161 (145-175) mm Hg vs 150 (134-166) mm Hg, P < .001) compared to hemodynamic stable patients. Interrater agreement between experts was 0.92 (95% CI, 0.89-0.94). The random forest classifier model showed excellent performance with an area under the receiver operating curve (AUROC) of 0.96, a sensitivity of 0.84, and specificity of 0.94. Based on the high sensitivity and specificity, the developed model is able to differentiate between clinically relevant hemodynamic instability and hemodynamic stable patients. This classification model will pave the way for future research concerning hemodynamic instability and its prevention.

Efficient and selective electrosynthesis of 4-aminophenol at circumneutral pH from the electrocatalytic reduction of nitrophenol over the nickel-iron phosphide modified electrode

The efficient and sustainable synthesis of 4-aminophenol (4-AP) from the electrocatalytic reduction of 4-nitrophenol (e-NPR) with water as the proton source relies on the development of robust electrocatalysts that readily expedite the kinetics of e-NPR and generate 4-AP with high selectivity at environmentally-benign conditions. In this study, we report on the efficient and sustainable electrosynthesis of 4-AP at circumneutral pH using the micro-structured nickel-iron phosphide modified electrode (CP|microNiFeP). The effects of the iron content of the prepared CP|microNiFeP electrodes as well as electrolysis conditions, including the electrolyte pH, applied potential, and electrolysis duration, on the electrosynthesis of 4-AP were thoroughly examined through a series of controlled-potential electrolyses (CPEs). Under optimal conditions, the CP|microNiFeP electrode exhibited a turnover frequency of 7.25 ± 0.05 h−1 for the generation of 4-AP at 0.0 V vs. RHE and achieved a high 4-NP conversion of 92.29 ± 1.47% with high selectivity for 4-AP generation (SAP:85.77 ± 2.21%) after 8-h CPE at −0.15 V vs. RHE in the H-cell. In addition, the scale-up electrosynthesis of 4-AP with a flow-type electrolyzer was also demonstrated. The 3-h electrolysis using the flow-type electrolyzer resulted in a high 4-NP conversion (93.84 ± 0.84%) with a high SAP (86.32 ± 1.05%). The possible reaction pathways of e-NPR have been proposed, and 4,4′-dihydroxyazobenzene and dimers were identified as the main side products.

Partitioning of respired CO2 in newly sprouted Moso bamboo culms.

Stem respiration (R s) plays a vital role in ecosystem carbon cycling. However, the measured efflux on the stem surface (E s) is not always in situ R s but only part of it. A previously proposed mass balance framework (MBF) attempted to explore the multiple partitioning pathways of R s, including sap-flow-transported and internal storage of R s, in addition to E s. This study proposed stem photosynthesis as an additional partitioning pathway to the MBF. Correspondingly, a double-chamber apparatus was designed and applied on newly sprouted Moso bamboo (Phyllostachys edulis) in leafless and leaved stages. R s of newly sprouted bamboo were twice as high in the leafless stage (7.41 ± 2.66 μmol m-2 s-1) than in the leaved stage (3.47 ± 2.43 μmol m-2 s-1). E s accounted for ~80% of R s, while sap flow may take away ~2% of R s in both leafless and leaved stages. Culm photosynthesis accounted for ~9% and 13% of R s, respectively. Carbon sequestration from culm photosynthesis accounted for approximately 2% of the aboveground bamboo biomass in the leafless stage. High culm photosynthesis but low sap flow during the leafless stage and vice versa during the leaved stage make bamboo an outstanding choice for exploring the MBF.

A root functional-structural model allows assessment of the effects of water deficit on water and solute transport parameters.

Root water uptake is driven by a combination of hydrostatic and osmotic forces. Water transport was characterized in primary roots of maize seedlings grown hydroponically under standard and water deficit (WD) conditions, as induced by addition of 150 g l-1 polyethylene glycol 8000 (water potential= -0.336 MPa). Flow measurements were performed using the pressure chamber technique in intact roots or on progressively cut root system architectures. To account for the concomitant transport of water and solutes in roots under WD, we developed within realistic root system architectures a hydraulic tree model integrating both solute pumping and leak. This model explains the high spontaneous sap exudation of roots grown in standard conditions, the non-linearity of pressure-flow relationships, and negative fluxes observed under WD conditions at low external hydrostatic pressure. The model also reveals the heterogeneity of driving forces and elementary radial flows throughout the root system architecture, and how this heterogeneity depends on both plant treatment and water transport mode. The full set of flow measurement data obtained from individual roots grown under standard or WD conditions was used in an inverse modeling approach to determine their respective radial and axial hydraulic conductivities. This approach allows resolution of the dramatic effects of WD on these two components.

Assessing plant uptake of organic contaminants by food crops tomato, wheat, and corn through sap concentration factor

This study investigated uptake of two organic compounds including hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and exogenous caffeine by tomato (Solanum lycopersicum L.), corn (Zea mays L.), and wheat (Triticum aestivum L.). The plants were grown in a growth chamber under recommended conditions and then were exposed to these compounds for 19 days. The uptake of the compounds was measured by sap concentration factor. The plant samples (stem transpiration stream) and solution in the exposure media were taken and analyzed by high performance liquid chromatography-tandem mass spectrometry. The plant stem samples were analyzed after a freeze-thaw centrifugation process. The average sap concentration factor for the RDX by tomato, wheat, and corn was 0.71, 0.67, and 0.65. The average sap concentration factor for the exogenous caffeine by tomato, wheat, and corn was 0.72, 0.50, and 0.34. These relatively high sap concentration factor values were expected as available predictive models offer high sap concentration factor values for moderately hydrophobic and hydrophilic compounds. The generated sap concentration factor values for the RDX and exogenous caffeine are important for improving the accuracy of previously developed machine learning models predicting the uptake and translocation of emerging contaminants.

Prevalence and Effect of Stroke Associated Pneumonia on in-Hospital Stay, Mortality and Functional Outcome at Discharge from Hospital

Background and Aim: Stroke is the most prominent cause of morbidity and mortality worldwide especially in developing countries. The stroke outcome mainly related to the presence of complications and severity. Stroke associated pneumonia is the post stroke infection significantly associated with a longer hospitalization, increased risk of hospital mortality, and functional outcomes. There is scarcity of data regarding stroke associated pneumonia on a local basis in the developing countries. Therefore, present study aimed to find out the prevalence and effect of stroke associated pneumonia on in-hospital stay, mortality, and function outcome. Methodology: This observational prospective study was conducted on 500 stroke patients in the Department of Neurology and Medicine, Jinnah Hospital, Lahore from April 2021 to March 2022. Prior to study conduction, written informed consent and ethical approval was taken. All the participants were recruited for this study. Stroke was diagnosed based on relevant clinical history, brain imaging either by CT scan or MRI, and focused physical examination. Stroke patients of either gender above 18 years age with acute ischemic or hemorrhagic stroke and given written consent were included. All those patients who are already having disability due to previous stroke and other neurological or non-neurological issues were excluded from study. Baseline characteristics were recorded. SPSS version 25 was used for data analysis. Results: Of the total 500 stroke patients, there were 232 (46.4%) male and 268 (53.6%) females. The overall mean age was 62.4 ± 12.6 years. The prevalence of ischemic and hemorrhagic stroke was 334 (66.8%) and 166 (33.2%) respectively among 500 stroke patients. Hemiparesis was the most prevalent neurological findings 464 (92.8%) followed by facial palsy 432 (86.4%) and swallowing disturbance 262 (52.4%). About 186 (37.2%) stroke patients were complicated by stroke associated pneumonia. Multivariate regression analysis was used and revealed that stroke associated pneumonia could be developed in older age patients &gt; 70 years Adjusted odd ratio AOR= 3.862 (1.21-12.86) (p=0.031) who suffered from swallowing disturbance AOR= 4.728, (2.415-9.102) (p&lt;0.001), epileptic seizures AOR= 2.749 (1.315-5.681) (p&lt;0.001), and moderate to severe stroke AOR= 6.183 (2.036-17.647) (p&lt;0.001) (NIHSS=16-21). Conclusion: The present study concluded that prevalence of SAP was 37.2%. Stroke associated pneumonia is a significant medical issue or complications in stroke patients. Furthermore, older stroke patients with epileptic seizure, swallowing disturbance, and stroke severity from moderate to severe were the risk factors for increasing stroke associated pneumonia. Close monitoring and effective intervention might be needed for high risk SAP in stroke patients. Keywords: Stroke associated pneumonia, Functional outcome, Mortality, Hospital stay, Stroke

Yield and quality properties of alfalfa (Medicago sativa L.) and their influencing factors in China

Alfalfa (Medicago sativa L.) is the most valuable perennial forage crop, and assessing its yield and quality properties is essential to evaluate forage value of livestock production. However, regional patterns and controlling factors of the yield and quality of alfalfa have not been well documented. In this study, using a dataset of 7166 observations from 301 sites across the country collected from 334 publications, we explored the relationships between the yield and quality properties of alfalfa in China and the effects of environmental factors and management practices on them. The average dry matter yield of alfalfa was 11.18 ± 6.69 Mg ha-1, with average crude protein, ether extract, crude fiber, acid detergent fiber, neutral detergent fiber, crude ash, nitrogen-free extract, calcium, phosphorus and relative feed values of 19.05 ± 2.87%, 2.62 ± 0.97%, 27.16 ± 5.21%, 31.29 ± 5.58%, 40.48 ± 6.34%, 9.49 ± 1.59%, 38.67 ± 7.49%, 1.68 ± 0.55%, 0.25 ± 0.12%, and 151 ± 31.94, respectively. Alfalfa quality decreased with increasing yield. Geographically, alfalfa had higher yield and crude protein content in South China than in other regions. Quality was positively correlated with both precipitation and temperature, while yield showed a positive relationship with temperature but no significant relationship with precipitation. High soil nutrient availability (e. g., soil available nitrogen, SAN; soil available phosphorus, SAP; soil available potassium, SAK) improved the yield, while high SAN and SAP contents increased the crude protein content. The alfalfa yield increased and the quality decreased with advancing maturity and age, whereas increasing the number of harvests may benefit the quality. This study documents comprehensive information on the yield and quality of alfalfa and provides insights for policy makers for the effective management and sustainable development of alfalfa production.

Screening of tall fescue genotypes for relative water content and osmotic potential under drought stress

AbstractBackgroundTall fescue (Festuca arundinacea Schreb.) is an important cool‐season perennial grass. Its persistence and forage yield can be severely affected by drought stresses during the hot, dry summers of the southern USA.MethodsOne thousand tall fescue genotypes were evaluated in the greenhouse for high relative water content (RWC) and low cell sap osmotic potential (OP). Fifty contrasting genotypes for the two traits were identified and used in further greenhouse and field studies. These genotypes were also screened with 30% PEG8000. Root and shoot characteristics were studied in 10 genotypes.ResultsThe genotypes differed for RWC (33.7%–97.3%, mean: 79.7%) and had an almost fivefold difference in OP (−0.5 to −2.4 MPa, mean: −1.2 MPa). Significant variation (p &lt; 0.001) for the main effects of environment and genotypes was found for RWC and OP. Apart from the greenhouse trial, no correlation was found between RWC and OP, indicating that differences in RWC might have been due to factors other than osmotic adjustment. Genotypes with either long roots or high root weights, and high root/shoot ratios demonstrated high RWC and low OP.ConclusionsGenotypes with consistently high RWC and low OP were identified and used for the development of mapping populations and transcriptome studies.

Sap Flow Velocity in Fraxinus pennsylvanica in Response to Water Stress and Microclimatic Variables.

In arid and semiarid regions with water shortage, forestry development is limited by water availability. Understanding how tree sap flow responds to water stress and microclimatic variables is essential for the management of trees and the understanding of the eco-physiological properties of trees in arid areas. In the city of Tianjin in northern China, we measured the sap flow of Fraxinus pennsylvanica, a widely distributed urban greening tree species in semiarid regions of China. We measured the sap flow in four F. pennsylvanica trees over 6 months (April–September 2021), using a thermal diffusion probe method, and simultaneously monitored microclimatic variables and soil moisture. Results indicated that high nighttime sap flow velocity might be produced under the water stress condition. In addition, the nighttime sap flow velocity under the water stress condition was more susceptible to the combined effects of meteorological factors at night. The daytime sap flow velocity exerted a highly significant positive effect on the nighttime sap flow velocity during the whole research period, and the model fit was higher in the early growing season than that in the late growing season (early growing season: R2 = 0.51, P < 0.01; late growing season: R2 = 0.36, P < 0.01). Vapor pressure deficit had a positive effect on daytime sap flow. However, net vapor pressure deficit restrained daytime sap flow velocity when the intercorrelation between the microclimatic variables was removed. Our study highlights that drought areas perhaps have higher nighttime sap flow and that more emphasis should be placed on nighttime sap flow and the response of nighttime sap flow to microclimatic variables. In addition, the influence of other microclimatic variables on vapor pressure deficit needs to be considered when analyzing the relationship between daytime sap flow and vapor pressure deficit. An increase in net VPD can suppress the daytime sap flow.

Stem respiration and growth in a central Amazon rainforest

Key messageAnnual stem CO2 efflux increases with stem wood production rates and are inhibited by daily moisture stress.Tropical forests cycle a large amount of CO2 between the land and atmosphere, with a substantial portion of the return flux due tree respiratory processes. However, in situ estimates of woody tissue respiratory fluxes and carbon use efficiencies (CUEW) and their dependencies on physiological processes including stem wood production (Pw) and transpiration in tropical forests remain scarce. Here, we synthesize monthly Pw and daytime stem CO2 efflux (ES) measurements over 1 year from 80 trees with variable biomass accumulation rates in the central Amazon. On average, carbon flux to woody tissues, expressed in the same stem area normalized units as ES, averaged 0.90 ± 1.2 µmol m−2 s−1 for Pw, and 0.55 ± 0.33 µmol m−2 s−1 for daytime ES. A positive linear correlation was found between stem growth rates and stem CO2 efflux, with respiratory carbon loss equivalent to 15 ± 3% of stem carbon accrual. CUEW of stems was non-linearly correlated with growth and was as high as 77–87% for a fast-growing tree. Diurnal measurements of stem CO2 efflux for three individuals showed a daytime reduction of ES by 15–50% during periods of high sap flow and transpiration. The results demonstrate that high daytime ES fluxes are associated with high CUEW during fast tree growth, reaching higher values than previously observed in the Amazon Basin (e.g., maximum CUEW up to 77–87%, versus 30–56%). The observations are consistent with the emerging view that diurnal dynamics of stem water status influences growth processes and associated respiratory metabolism.

Exogenous Abscisic Acid Priming Modulates Water Relation Responses of Two Tomato Genotypes With Contrasting Endogenous Abscisic Acid Levels to Progressive Soil Drying Under Elevated CO2.

Plants have evolved multiple strategies to survive and adapt when confronting the changing climate, including elevated CO2 concentration (e[CO2]) and intensified drought stress. To explore the role of abscisic acid (ABA) in modulating the response of plant water relation characteristics to progressive drought under ambient (a[CO2], 400 ppm) and e[CO2] (800 ppm) growth environments, two tomato (Solanum lycopersicum) genotypes, Ailsa Craig (AC) and its ABA-deficient mutant (flacca), were grown in pots, treated with or without exogenous ABA, and exposed to progressive soil drying until all plant available water in the pot was depleted. The results showed that exogenous ABA application improved leaf water potential, osmotic potential, and leaf turgor and increased leaf ABA concentrations ([ABA]leaf) in AC and flacca. In both genotypes, exogenous ABA application decreased stomatal pore aperture and stomatal conductance (gs), though these effects were less pronounced in e[CO2]-grown AC and gs of ABA-treated flacca was gradually increased until a soil water threshold after which gs started to decline. In addition, ABA-treated flacca showed a partly restored stomatal drought response even when the accumulation of [ABA]leaf was vanished, implying [ABA]leaf might be not directly responsible for the decreased gs. During soil drying, [ABA]leaf remained higher in e[CO2]-grown plants compared with those under a[CO2], and a high xylem sap ABA concentration was also noticed in the ABA-treated flacca especially under e[CO2], suggesting that e[CO2] might exert an effect on ABA degradation and/or redistribution. Collectively, a fine-tune ABA homeostasis under combined e[CO2] and drought stress allowed plants to optimize leaf gas exchange and plant water relations, yet more detailed research regarding ABA metabolism is still needed to fully explore the role of ABA in mediating plant physiological response to future drier and CO2-enriched climate.

Potential of Sorghum Varieties as Biofuel

The downside of fossil fuels as non-renewable energy resources in Indonesia has led to invent alternative energy resources. One of alternative sources is biofuels, which are derived from organic compound that originated from plants and living creatures. Here, we used sorghum as a source of biofuels, but current knowledge of sorghum cultivation on dry land is limited. This study aims to determine the influence of sorghum genotypes on their growth and yield in a dry land, and to analyze the potential of sorghum as biofuels. This research was carried out in low land, on vertisol soil, from August to November 2020. We applied a completely randomized block design with one factor and 3 replications. Seven sorghum varieties were identified namely Numbu, Super 1, Suri 3, Keller, Kawali, Black Sorghum, and Bioguma-2. The results showed that each variety had different genetical properties leading to various growth rates in both vegetative and generative phases. Our finding revealed that Keller variety was the most productive sorghum plant as it produced the highest sugar content (20°Brix). Also, Keller was the tallest plants (&gt;300 cm) compared to other varieties. Bioguma-2 was the second, which was proven by its longest stem (307 cm) and high stem sap content (18°Brix). Thus, we recommended the Keller and Bioguma-2 as the suitable sorghum variety to be utilized in biofuels manufacturing.

Measurement of low sap flux density in plants using the single needle heat pulse probe

Heat pulse probes are used worldwide to quantify sap flow in plants. Probes consisting of a single needle inserted into a plant have a simple physical configuration relative to multi-probe methods. The single probe also minimizes physical damage to plant tissue. Single probe methods are therefore increasingly used for sap flux density measurements. However, at low sap flux density values, existing single probe heat pulse (SPHP) methods cannot be used for accurate measurements. To increase the sensitivity of SPHP to low sap flux densities, this paper describes and validates a simplified expression of sap flow and heat transport under various heat inputs and finite heat pulse time intervals. To test this theoretical development, measurements were collected from SPHP probes inserted into mature poplar forest trees (Populus tomentosa Carrière) during the 2020 growing season. The results show that the new method can successfully monitor low sap flux density: the lowest measured heat pulse velocity was 3 cm h−1, which is an improvement from the original SPHP method (20 cm h−1). The improved SPHP method had a root mean square deviation (RMSD) of 1.63 cm h−1 in comparison with the heat ratio (HR) method. The proposed SPHP method is therefore suitable for quantifying both low and high sap flux densities.

Why is phloem sap nitrate kept low?

Since the first description of phloem sap composition nearly 60 years ago, it is generally assumed that phloem sap does not contain nitrate and that there is little or no backflow of nitrate from shoots to roots. While it is true that nitrate can occasionally be absent from phloem sap, there is now substantial evidence that phloem can carry nitrate and furthermore, transporters involved in nitrate redistribution to shoot sink organs and roots have been found. This raises the question of why nitrate may or may not be present in phloem sap, why its concentration is generally kept low, and whether plant shoot-root nutrient cycling also involves nitrate. We propose here that phloem sap nitrate is not only an essential component of plant nutritional signaling but also contributes to physical properties of phloem sap and as such, its concentration must be controlled to ensure proper coordination of plant development and nutrient transport. This article is protected by copyright. All rights reserved.

Prevention of hypotension during elective cesarean section with a combination of colloid co-load and a continuous infusion of a vasoconstrictive agent: A comparative randomized study

Background: Spinal anesthesia is considered the anesthetic technique of choice in cesarean section but it can be frequently complicated by hypotension, with occasionally serious consequences for both the mother and fetus. One of the standard techniques used in the prevention of maternal hypotension is the administration of a continuous phenylephrine infusion. However, phenylephrine can lead to baroreceptor-mediated reflex bradycardia with untoward consequences for the maternal cardiac output. Nowadays, noradrenaline has been proposed as an alternative agent in this context, since due to its additional weak dose-dependent β-action, it can be associated with an inferior incidence of maternal bradycardia and thus of propensity to decrease the cardiac output. Colloid co-hydration has also been proven to be an effective technique in the prevention of maternal hypotension. This double-blinded, prospective randomized study aimed to investigate whether the addition of a fixed rate phenylephrine infusion or noradrenaline infusion to a colloid co-hydration regimen results in better maternal hemodynamic status or in a more favorable metabolic profile in the newborn as compared to the administration of colloids alone without any vasoconstrictor during elective cesarean section under combined spinal-epidural anesthesia. Materials and methods: One hundred-twenty parturients were randomized to either phenylephrine 50 μg/min (group P) or noradrenaline 4 μg/min (group N) or placebo (group C). All infusions had been prepared in identical syringes and the infusion rate was 30 mL/h in order to ensure the “blindness” of the study. As soon as the spinal injection started, all groups were administered 10 mL/kg of hydroxyethyl starch (HES) solution simultaneously with the onset of vasoconstrictor infusion. The primary end-point of the study was the incidence of maternal hypotension (SAP <80% of baseline). Additionally, maternal hemodynamics at specific time-points were recorded using non-invasive technology (Edwards Lifesciences ClearSight System) as well as the incidence of reactive hypertension, bradycardia, the requirement for bolus vasoconstrictor administration and the fetal acid-base status, the umbilical venous and arterial blood gases and the newborn Apgar score. Results: The incidence of maternal hypotension was higher in group C than in group P and also higher in group C than in group N (p = 0.024 and 0.073, respectively). The need of bolus administration of vasoconstrictor was higher in group C than in group P and also higher in group C than in group N (p = 0.001 and 0.003, respectively). The incidence of bradycardia was higher in group P than in group N (p = 0.018). The incidence of reactive hypertension was higher in group P than in group N and also higher in group P than in group C (p = 0.029 and 0.005, respectively). The need of modification of the infusion rate was higher in group P than in group N and also higher in group P than in group C (p < 0.001 και p = 0.002, respectively). The fetal pH of the umbilical vein was higher in groups N and P than in group C (p < 0.001), the fetal pO2 of the umbilical vein was higher in group N than in group C (p = 0.023) and fetal blood glucose concentration was higher in group N than in group C (p = 0.025) as well as in group N than group P with no statistical significance. Higher systematic vascular resistance index (SVRI) and higher SAP were observed at specific time-points in group P versus the other two groups. Finally, post-delivery Apgar scores were similar in all groups. Conclusions: The combination of a fixed-rate infusion of noradrenaline with the co-administration of colloid seems to be the most effective in the obstetric management of the parturient during cesarean section under regional anesthesia since it ensures maternal hemodynamic stability and a favorable metabolic profile in the newborn. This regimen seems to be superior to either a combination of colloid co-administration with a fixed rate of phenylephrine or to the administration of colloid alone without any vasoconstrictor agent. The higher concentration of fetal blood glucose in group N might be due to a catecholamine-induced glucose metabolism activation and due to a β-receptor-mediated decrease of insulin release.

Using the clinical information system and self-supervision to rationalize the need for antibiotic stewardship: An interventional study in a 2000-bed university hospital

To describe the usefulness of electronic medical records (EMRs) and a computerized physician order entry (CPOE) system to support and assess an antimicrobial stewardship programme (ASP). At the study hospital, infectious diseases specialists supervise antimicrobial prescription when solicited by physicians in charge of patients. From January to October 2015, treatment days of antibiotic prescription, supervised or unsupervised by infectious disease specialists (SAP or UAP, respectively) in all wards, except intensive care units emergency department, bone marrow transplantation units, and paediatric units, were calculated. Embedding recommendations on carbapenem indications as a checklist into the CPOE system, a self-administered ASP was implemented in 2017. EMRs were reviewed to determine global compliance with carbapenem prescription guidelines (combining introduction of therapy and 72-h assessment) before and after implementation of a self-administered ASP in departments with a low SAP rate for these antibiotics. Among 16 090 prescriptions extracted, 19.9% were SAPs. Three patterns of prescription were identified. The first pattern (amoxicillin-clavulanate, ceftriaxone) was characterized by a high UAP rate in every department, the second pattern (cloxacillin, rifampin) was characterized by a high SAP rate in every department, and the third pattern (broad-spectrum beta-lactams) was characterized by heterogeneous distribution of SAP/UAP among departments. Carbapenem prescription was reviewed in five departments with a low SAP rate for carbapenems over 6 months: 94 before and 107 after implementation of the self-administered ASP. Global compliance with guidelines increased significantly from 22% to 37% (risk difference 15%, 95% confidence interval 2.3-28.5%; P=0.02). A clinical information system may help to rationalize antibiotic stewardship in a context of scarce medical resources. Mapping of antibiotic prescriptions and self-supervision are efficient, complementary and easy-to-implement tools.

Propagation Studies in Sapodilla [Manilkara zapota (L.) P. Royen]: A Review

Sapota [Manilkara zapota (L) P. Royen] is an important commercial fruit crop of Sapotaceae family grown for fresh fruits and chicle production. Sapota when propagated by vegetative means, produce true to type plant material and reduces juvenile period and result in early commercial production. Various propagation techniques on different rootstocks were tried for the purpose. Among different rootstocks, khirni (Manilkara hexandra) was found most successful and is used for commercial plant propagation as it possesses high graft compatibility with sapota and plants produce fruits of excellent quality with high yield. Various vegetative propagation techniques have been standardized and used on large scale depending upon season and region. The general techniques used for sapota propagation are softwood grafting, veneer grafting, side grafting, inarching and air layering. Softwood grafting is employed in regions with moderate temperature and high relative humidity which prevent desiccation of scion stick. Veneer and side grafting using mature scion stick is also found effective in regions with variable climates. Inarching technique possess high graft survival rate and is practiced by private nurseries. Propagation through cuttings is not successful in sapota even when treated with rooting hormones. Micro-propagation in sapota by tissue culture techniques have been tried but application remains limited to academics only. This may be due to high phenolic contents and sap exudation in explant. Special protocols for successful root and shoot regeneration are required to be standardized for commercial scale plant propagation.

Water and Soil Nutrient Dynamics of Huanglongbing-Affected Citrus Trees as Impacted by Ground-Applied Nutrients

The decrease in the rate of inflow and outflow of water—and thereby the uptake of plant nutrients as the result of Huanglongbing (HLB or citrus greening)—leads to a decline in overall tree growth and the development of nutrient deficiencies in HLB-affected citrus trees. This study was conducted at the University of Florida, Southwest Florida Research and Education Center (SWFREC) near Immokalee, FL from January 2017 through December 2019. The objective of the study was to determine the effect of rootstocks, nutrient type, rate, and frequency of applications on leaf area index (LAI), water relations (stomatal conductance [gs], stem water potential [Ψw], and sap flow), soil nutrient accumulation, and dynamics under HLB-affected citrus trees. The experiment was arranged in a split-split plot design that consisted of two types of rootstocks, three nitrogen (N) rates, three soil-applied secondary macronutrients, and an untreated control replicated four times. LAI significantly increased in response to the secondary macronutrients compared with uncontrolled trees. A significantly greater gs, and thus a decline in Ψw, was a manifestation of higher sap flow per unit LA (leaf area) and moisture stress for trees budded on Swingle (Swc) than Cleopatra (Cleo) rootstocks, respectively. The hourly sap flow showed significantly less water consumption per unit LA for trees that received a full dose of Ca or Mg nutrition than Ca + Mg treated and untreated control trees. The soil nutrient concentrations were consistently higher in the topmost soil depth (0–15 cm) than the two lower soil depths (15–30 cm, 30–45 cm). Mobile nutrients: soil nitrate–nitrogen (NO3-N) and Mg2+ Mg2+, Mn2+, Zn2+, and B leached to the lower soil (15–30 cm) depth during the summer season. However, the multiple split applications of N as Best Management Practices (BMPs) and optimum irrigation scheduling based on reference evapotranspiration (ETo) maintained soil available N (ammonium nitrogen [NH4-N] and NO3-N) below 4.0 mg kg−1, which was a magnitude 2.0–4.0× less than the conventional N applications. Soil NH4-N and NO3-N leached to the two lower soil depths during the rainy summer season only when trees received the highest N rate (280 kg ha−1), suggesting a lower citrus N requirement. Therefore, 224 kg ha−1 N coupled with a full Ca or Mg dose could be the recommended rate for HLB-affected citrus trees.

Water stress, sap flow and transpiration for medium and highly drought resistant poplars grown in the semiarid Canadian prairie

Sap flow was measured to determine transpiration rates for CanAm and Walker poplars grown in the semiarid Canadian prairie. CanAm poplars had higher sap flow rates and were better able to supply water to actively growing regions for all water availabilities (well-watered to drought). CanAm poplars were better able to survive drought.

Temporal and spatial patterns of abundance and occurrence of planktonic shrimps in the Songkhla Lagoon System, southern Thailand

Temporal and spatial distributions of planktonic shrimps from the hyperbenthos of Thale Sap and Thale Sap Songkhla lakes in the Songkhla Lagoon system, southern Thailand, were investigated using modified Riley push nets with a mesh size of 0.5 mm between June 2017 and June 2018. Three species of Mysida and two species of Dendrobranchiata shrimps were revealed, among which Nanomysis siamensis was dominant, representing more than 90% of the catch throughout the year. The Songkhla Lagoon system experiences extreme changes in temperature, salinity, pH, and water levels due to seasonal monsoons. A significant difference in the planktonic shrimp assemblages between Thale Sap and Thale Sap Songkhla was observed across the sampling months. Significant differences in the assemblage structure were also evident between Thale Sap and Thale Sap Songkhla and among sampling months. Dissimilar assemblage patterns were prominent temporally during the shift from southwest to northeast monsoon seasons and from the intermediate to southwest monsoon. Lake (Thale Sap or Thale Sap Songkhla) was the most important environmental parameter affecting occurrence patterns for N. siamensis, Mesopodopsis tenuipes, and Belzebub hanseni in the Songkhla Lagoon system. Salinity governed the spatial distribution of M. tenuipes and B. hanseni. Nanomysis siamensis was the only species that was regularly present in high abundance in Thale Sap and Thale Sap Songkhla over the entire salinity range. This suggest that N. siamensis is likely a resident species of the Songkhla Lagoon system.