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Humans often face the challenge of making decisions between ambiguous options. The level of ambiguity in decision-making has been linked to activity in the parietal cortex, but its exact computational role remains elusive. To test the hypothesis that the parietal cortex plays a causal role in computing ambiguous probabilities, we conducted consecutive fMRI and TMS-EEG studies. We found that participants assigned unknown probabilities to objective probabilities, elevating the uncertainty of their decisions. Parietal cortex activity correlated with the objective degree of ambiguity and with a process that underestimates the uncertainty during decision-making. Conversely, the midcingulate cortex (MCC) encodes prediction errors and increases its connectivity with the parietal cortex during outcome processing. Disruption of the parietal activity increased the uncertainty evaluation of the options, decreasing cingulate cortex oscillations during outcome evaluation and lateral frontal oscillations related to value ambiguous probability. These results provide evidence for a causal role of the parietal cortex in computing uncertainty during ambiguous decisions made by humans.
Subject(s)
Brain Mapping , Decision Making , Humans , Brain Mapping/methods , Risk-Taking , Uncertainty , Parietal Lobe , Magnetic Resonance Imaging/methodsABSTRACT
BACKGROUND & AIMS: Understanding the burden of pancreatic cystic lesions (PCLs) in the general population is important for clinicians and policymakers. In this systematic review, we sought to estimate the global prevalence of PCLs using magnetic resonance imaging (MRI) and to investigate factors that contribute to its variation. METHODS: We searched MEDLINE, EMBASE, and Cochrane Central, from database inception through February 2023. We included full-text articles that reported the prevalence of PCLs using MRI in the general population. A proportional meta-analysis was performed, and the prevalence of PCLs was pooled using a random-effects model. RESULTS: Fifteen studies with 65,607 subjects were identified. The pooled prevalence of PCLs was 16% (95% confidence interval [CI], 13%-18%; I2 = 99%), most of which were under 10 mm. Age-specific prevalence of PCLs increased from 9% (95% CI, 7%-12%) at 50 to 59 years, to 18% (95% CI, 14%-22%) at 60 to 69 years, 26% (95% CI, 20%-33%) at 70 to 79 years, and 38% at 80 years and above (95% CI, 25%-52%). There was no difference in prevalence between sexes. Subgroup analysis showed higher PCL prevalence when imaging findings were confirmed by independent radiologist(s) (25%; 95% CI, 16%-33%) than when chart review alone was used (5%; 95% CI, 4%-7%; P < .01). There was no independent association of PCL prevalence with geographic location (Europe, North America, or Asia), MRI indication (screening vs evaluation of non-pancreatic pathology), enrollment period, sample size, magnet strength (1.5 vs 3 tesla), and MRI sequence (magnetic resonance cholangiopancreatography vs no magnetic resonance cholangiopancreatography). CONCLUSION: In this systematic review, the global prevalence of PCLs using a highly sensitive noninvasive imaging modality ranged between 13% and 18%.
Subject(s)
Magnetic Resonance Imaging , Pancreatic Cyst , Female , Humans , Male , Global Health , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/statistics & numerical data , Pancreas/diagnostic imaging , Pancreas/pathology , Pancreatic Cyst/epidemiology , Pancreatic Cyst/diagnostic imaging , PrevalenceABSTRACT
INTRODUCTION: Inadequate bowel preparation (IBP) before colonoscopy remains a common problem. This meta-analysis aimed to assess the risk factors associated with IBP. METHODS: We searched multiple databases for studies that assessed risk factors for IBP after adjustment and reported the data as adjusted odds ratios with 95% confidence intervals. Meta-analyses were conducted using a random-effects model, and pooled adjusted odds ratios for risk factors reported in ≥ 3 studies were constructed. RESULTS: One hundred fifty-four studies with 358,257 participants were included. We analyzed 48 unique risk factors. Sociodemographic predictors of IBP were Medicaid insurance, obesity, current tobacco use, age ≥ 65 years, Black race, low education level, male sex, and unmarried status. Comorbidity-related predictors of IBP were any psychiatric disease, cirrhosis, American Society of Anesthesiologists (ASA) class ≥ 3, poor functional status, constipation, diabetes, previous abdominopelvic surgery, and hematochezia. Medication-related predictors of IBP were tricyclic antidepressants, antidepressants, opioids, nontricyclic antidepressants, and calcium channel blockers. Preparation/procedure-related predictors of IBP were brown liquid rectal effluent, any incomplete bowel preparation (BP) intake, lack of split-dose BP, increased BP-to-defecation interval, any nonadherence to dietary instructions, increased BP-to-colonoscopy interval, any BP intolerance, previous IBP, and inpatient status. Although afternoon colonoscopy was a predictor of IBP, subgroup analysis of prospective studies revealed no significant association. DISCUSSION: Our meta-analysis focused on adjusted risk factors to provide precise estimates of the most important risk factors for IBP. Our findings could help develop a validated prediction model to identify high-risk patients for IBP, improve colonoscopy outcomes, reduce the need for repeat colonoscopies, and reduce associated healthcare costs.
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INTRODUCTION: Diagnostic paracentesis is recommended for patients with cirrhosis admitted to the hospital, but adherence is suboptimal with unclear impact on clinical outcomes. The aim of this meta-analysis was to assess the outcomes of early vs delayed diagnostic paracentesis among hospitalized patients with cirrhosis and ascites. METHODS: We searched multiple databases for studies comparing early vs delayed diagnostic paracentesis among hospitalized patients with cirrhosis and ascites. The pooled odds ratio (OR) and mean difference with confidence intervals (CIs) for proportional and continuous variables were calculated using the random-effects model. Early diagnostic paracentesis was defined as receiving diagnostic paracentesis within 12-24 hours of admission. The primary outcome was in-hospital mortality. Secondary outcomes were length of hospital stay, acute kidney injury, and 30-day readmission. RESULTS: Seven studies (n = 78,744) (n = 45,533 early vs n = 33,211 delayed diagnostic paracentesis) were included. Early diagnostic paracentesis was associated with lower in-hospital mortality (OR 0.61, 95% CI 0.46-0.82, P = 0.001), length of hospital stay (mean difference -4.85 days; 95% CI -6.45 to -3.20; P < 0.001), and acute kidney injury (OR 0.62, 95% CI 0.42-0.92, P = 0.02) compared with delayed diagnostic paracentesis, with similar 30-day readmission (OR 1.11, 95% CI 0.52-2.39, P = 0.79). Subgroup analysis revealed consistent results for in-hospital mortality whether early diagnostic paracentesis performed within 12 hours (OR 0.51, 95% CI 0.32-0.79, P = 0.003, I2 = 0%) or within 24 hours of admission (OR 0.67, 95% CI 0.45-0.98, P = 0.04, I2 = 82%). Notably, the mortality OR was numerically lower when diagnostic paracentesis was performed within 12 hours, and the results were precise and homogenous ( I2 = 0%). DISCUSSION: Findings from this meta-analysis suggest that early diagnostic paracentesis is associated with better patient outcomes. Early diagnostic paracentesis within 12 hours of admission may be associated with the greatest mortality benefit. Data from large-scale randomized trials are needed to validate our findings, especially if there is a greater mortality benefit for early diagnostic paracentesis within 12 hours.
Subject(s)
Ascites , Early Diagnosis , Hospital Mortality , Length of Stay , Liver Cirrhosis , Paracentesis , Humans , Liver Cirrhosis/complications , Liver Cirrhosis/therapy , Liver Cirrhosis/mortality , Ascites/therapy , Ascites/etiology , Length of Stay/statistics & numerical data , Acute Kidney Injury/therapy , Acute Kidney Injury/mortality , Acute Kidney Injury/diagnosis , Patient Readmission/statistics & numerical data , Hospitalization/statistics & numerical data , Delayed DiagnosisABSTRACT
INTRODUCTION: Acute necrotizing pancreatitis (ANP) complicates 15 % of acute pancreatitis cases and is associated with prolonged length of stay (LOS). There are limited studies exploring potential predictors. METHODS: We carried out a retrospective study of all consecutive patients presenting to a large referral healthcare system with ANP. Patients younger than 18 years of age, without confirmed glandular necrosis and with in-hospital mortality were excluded. Poisson regression was carried out to identify potential predictors of prolonged hospital stay. RESULTS: One hundred and sixty-two patients hospitalized between December 2016 and June 2020 were included. The median LOS was 12 days (range: 1-155 days). On multivariate analysis, organ dysfunction at presentation (Incidence rate ratio (IRR) 1.21, p = 0.01) or during admission (IRR 1.32, p = 0.001), Charlson Comorbidity Index scores (IRR 1.1 per CCI point, p < 0.001), known chronic pancreatitis (IRR 1.19, p = 0.03), concurrent (non-pancreas related) infections (IRR 1.13, p = 0.04), need for enteral tube placement (IRR 3.42, p < 0.001) and in-hospital interventions (IRR 1.48-2.85 depending on intervention, p < 0.001) were associated with increased LOS. For patients in the cohort to whom this applied, delayed hospital transfers (IRR 1.02, p < 0.001) and delayed start of enteral feeds (IRR 1.01, p = 0.017) contributed to increased overall LOS. CONCLUSION: We demonstrate that multiple factors including delayed transfers to hospitals with pancreaticobiliary expertise lead to increased length of hospitalization. We suggest various strategies that can be considered to target those gaps and may have a favorable effect on LOS.
Subject(s)
Pancreatitis, Acute Necrotizing , Humans , Length of Stay , Retrospective Studies , Acute Disease , HospitalsABSTRACT
Aerial blight, caused by the fungus Rhizoctonia solani anastomosis group (AG) 1-IA, is an economically important soybean disease in the mid-Southern United States. Management has relied on fungicide applications during the season, but there is an increasing prevalence of resistance to commonly used strobilurin fungicides and an urgent need to identify soybean varieties resistant to aerial blight. Because the patchy distribution of the pathogen complicates field variety screening, the present study aimed to develop a greenhouse screening protocol to identify soybean varieties resistant to aerial blight. For this, 88 pathogen isolates were collected from commercial fields and research farms across five Louisiana parishes, and 77% were confirmed to be R. solani AG1-IA. Three polymorphic codominant microsatellite markers were used to explore the genetic diversity of 43 R. solani AG1-IA isolates, which showed high genetic diversity, with 35 haplotypes in total and only two haplotypes common to two other locations. Six genetically diverse isolates were chosen and characterized for their virulence and fungicide sensitivity. The isolate AC2 was identified as the most virulent and was resistant to both active ingredients, azoxystrobin and pyraclostrobin, tested. The six isolates were used in greenhouse variety screening trials using a millet inoculation protocol. Of the 31 varieties screened, only Armor 48-D25 was classified as moderately resistant, and plant height to the first node influenced final disease severity. The study provides short-term solutions for growers to choose less susceptible varieties for planting and lays the foundation to characterize host resistance against this important soybean pathogen.
Subject(s)
Fungicides, Industrial , Glycine max , Plant Diseases , Rhizoctonia , Rhizoctonia/physiology , Rhizoctonia/genetics , Rhizoctonia/drug effects , Rhizoctonia/pathogenicity , Plant Diseases/microbiology , Glycine max/microbiology , Fungicides, Industrial/pharmacology , Disease Resistance/genetics , Strobilurins/pharmacology , Methacrylates/pharmacology , Genetic Variation , Microsatellite Repeats/genetics , Pyrazoles/pharmacology , Virulence/genetics , Louisiana , PyrimidinesABSTRACT
Anthropogenic activities, encompassing vast agricultural and industrial operations around the world, exert substantial pressure on the environment, culminating in profound ecological impacts. These activities exacerbate soil contamination problems with pollutants such as mercury (Hg) and chlorpyrifos (CPF) that are notable for their widespread presence and detrimental effects. The objective of this study is to evaluate the phytoremediation potential of Phaseolus vulgaris L., augmented with various combinations of biochar, mycorrhizal, and compost amendments, as a sustainable alternative for the remediation of soils contaminated with Hg and CPF. For this purpose, soil from a mining area with mercury contamination has been taken, to which CPF has been added in different concentrations. Then, previously germinated Phaseolus vulgaris L. seedlings with an average height of 10 cm were planted. Electrical conductivity, pH, organic matter, CPF, and Hg, as well as seedling growth parameters, have been evaluated to determine the processes of absorption of soil contaminants into the plant. A combination of biochar with mycorrhiza has been found to be an optimal choice for CPF and Hg remediation. However, all amendments have proven to be efficient in the remediation processes of the tested contaminants.
Subject(s)
Biodegradation, Environmental , Charcoal , Chlorpyrifos , Composting , Mercury , Mycorrhizae , Phaseolus , Soil Pollutants , Charcoal/chemistry , Phaseolus/metabolism , Soil Pollutants/metabolism , Mercury/metabolism , Mycorrhizae/metabolism , Chlorpyrifos/metabolism , Soil/chemistry , Seedlings/metabolismABSTRACT
AIM: The aim of the study was to determine whether overcooling (temperature <33°C) during passive hypothermia when transporting neonates with perinatal asphyxia increased the risk of short-term neurological injury. METHODS: A retrospective observational study was performed. Newborns transferred to the LaCardio neonatal unit between January 2021 and April 2022 with moderate and severe perinatal asphyxia and who received passive hypothermia during transport were included. A temperature of <33°C was considered overcooling. A composite outcome of neurological injury was defined by the presence of abnormalities on brain magnetic resonance imaging, video telemetry, seizure before discharge or both. RESULTS: The study included 101 newborns. A total of 18 neonates had a temperature <33°C after transportation. Neurological injuries were present in 21.8% of the temperature <33°C group and 78.2% of the temperature ≥33°C group. Temperature <33°C at the end of transport (aOR 9.2, 95% CI 1.1-77.3) were associated with neurological injury before discharge from the unit. CONCLUSION: During transportation, overcooling in neonates with asphyxia increases the risk of neurological injury before discharge from the neonatal unit. It is important to qualify the transport team with adequate training and equipment for therapeutic hypothermia.
Subject(s)
Asphyxia Neonatorum , Hypothermia, Induced , Hypothermia , Hypoxia-Ischemia, Brain , Female , Pregnancy , Infant, Newborn , Humans , Infant , Hypothermia/complications , Asphyxia/complications , Asphyxia/therapy , Colombia/epidemiology , Hypoxia-Ischemia, Brain/therapy , Hypoxia-Ischemia, Brain/complications , Hypothermia, Induced/adverse effects , Hospitals , Asphyxia Neonatorum/therapy , Asphyxia Neonatorum/complicationsABSTRACT
OBJECTIVE: Hypoglycemia is a frequent occurrence in chronic kidney disease patients due to alterations in glucose and insulin metabolism. However, there are sparse data examining the predictors and clinical implications of hypoglycemia including mortality risk among incident hemodialysis patients. DESIGN AND METHODS: Among 58,304 incident hemodialysis patients receiving care from a large national dialysis organization over 2007-2011, we examined clinical characteristics associated with risk of hypoglycemia, defined as a blood glucose concentration <70 mg/dL, in the first year of dialysis using expanded case-mix + laboratory logistic regression models. We then examined the association between hypoglycemia during the first year of dialysis with all-cause mortality using expanded case-mix + laboratory Cox models. RESULTS: In the first year of dialysis, hypoglycemia was observed among 16.8% of diabetic and 6.9% of nondiabetic incident hemodialysis patients. In adjusted logistic regression models, clinical characteristics associated with hypoglycemia included younger age, female sex, African-American race, presence of a central venous catheter, lower residual renal function, and longer dialysis session length. In the overall cohort, patients who experienced hypoglycemia had a higher risk of all-cause mortality risk (reference: absence of hypoglycemia): adjusted hazard ratio (95% confidence interval) 1.08 (1.04, 1.13). In stratified analyses, hypoglycemia was also associated with higher mortality risk in the diabetic and nondiabetic subgroups: adjusted hazard ratios (95% confidence interval's) 1.08 (1.04-1.13), and 1.17 (0.94-1.45), respectively. CONCLUSIONS: Hypoglycemia was a frequent occurrence among both diabetic and nondiabetic hemodialysis patients and was associated with a higher mortality risk. Further studies are needed to identify approaches that reduce hypoglycemia risk in the hemodialysis population.
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INTRODUCTION: In October 2019 in Chile, massive protests broke out in the so-called social uprising. The repressive response of the armed forces and Carabineros (Police) resulted in serious and mas-sive violations of human rights, with between 400 and 500 victims of ocular trauma caused mainly by shots from anti-riot shotguns, constituting the largest number of cases in the world linked to a single event. It is proposed to evaluate the different dimensions of the impact of ocular trauma due to state violence, using the concept of psychosocial trauma and a support model that integrates the medical-psychological and social dimensions. METHODS: Human rights violations of the period are described, focusing on cases of ocular trauma, and state and civil society responses. The requests of a survivors' organisations regarding truth, justice and reparation is presented. A clinical case of ocular trauma treated in our centre is analyzed. RESULTS: Survivors of ocular trauma manifest post-traumatic reactions regardless of the severity of their ocular injuries. The impact on the mental health of survi-vors of ocular trauma due to state violence is a phenomenon where the psychic and psychosocial im-pact of trauma due to socio-political violence intersects with the short- and long-term mental health effects. DISCUSSION: The impact of sociopolitical trauma must be understood considering both the in-dividual and social subject, considering their cultural, socioeconomic and political reality. Recovery from traumatic psychological injury must be addressed in its medical, sensory rehabilitation, psycho-logical and psychosocial dimensions, including processes of social recognition, search for justice and comprehensive reparation of damage. In contexts of impunity, a model is proposed that integrates rehabilitation with psycho-legal support, promotion of agency and organisation, within the frame-work of commitment to the movement and principles of human rights.
Subject(s)
Eye Injuries , Human Rights , Psychological Trauma , Humans , Chile , Eye Injuries/psychology , Psychological Trauma/psychology , Male , Adult , Survivors/psychology , Violence/psychologyABSTRACT
Pancreatic cancer is on the rise and expected to become the second leading cause of cancer-related death by 2030. Up to a one-fifth of pancreatic cancers may arise from mucinous pancreatic cysts, which are frequently present in the general population. Currently, surgical resection is the only curative approach for pancreatic cancer and its cystic precursors. However, only a dismal proportion of patients are eligible for surgery. Therefore, novel treatment approaches to treat pancreatic cancer and precancerous pancreatic cysts are needed. Endoscopic ultrasound (EUS)-guided ablation is an emerging minimally invasive method to treat pancreatic cancer and premalignant pancreatic cysts. Different ablative modalities have been used including alcohol, chemotherapy agents, and radiofrequency ablation. Cumulative data over the past two decades have shown that endoscopic ablation of mucinous pancreatic cysts can lead to cyst resolution in a significant proportion of the treated cysts. Furthermore, novel data are emerging about the ability to endoscopically ablate early and locally advanced pancreatic cancer. In this review, we aim to summarize the available data on the efficacy and safety of the different EUS-ablation modalities for the management of premalignant pancreatic cysts and pancreatic cancer.
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Autism spectrum disorder (ASD) is a neurodevelopmental condition that exhibits a widely heterogeneous range of social and cognitive symptoms. This feature has challenged a broad comprehension of this neurodevelopmental disorder and therapeutic efforts to address its difficulties. Current therapeutic strategies have focused primarily on treating behavioral symptoms rather than on brain psychophysiology. During the past years, the emergence of non-invasive brain stimulation techniques (NIBS) has opened alternatives to the design of potential combined treatments focused on the neurophysiopathology of neuropsychiatric disorders like ASD. Such interventions require identifying the key brain mechanisms underlying the symptomatology and cognitive features. Evidence has shown alterations in oscillatory features of the neural ensembles associated with cognitive functions in ASD. In this line, we elaborated a systematic revision of the evidence of alterations in brain oscillations that underlie key cognitive processes that have been shown to be affected in ASD during childhood and adolescence, namely, social cognition, attention, working memory, inhibitory control, and cognitive flexibility. This knowledge could contribute to developing therapies based on NIBS to improve these processes in populations with ASD.
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BACKGROUND: The ageing population has increased the prevalence of disabling and high-cost diseases, such as dementia and mild cognitive impairment (MCI). The latter can be considered a prodromal phase of some dementias and a critical stage for interventions to postpone the impairment of functionality. Working memory (WM) is a pivotal cognitive function, representing the fundamental element of executive functions. This project proposes an intervention protocol to enhance WM in these users, combining cognitive training with transcranial electrical stimulation of alternating current (tACS). This technique has been suggested to enhance the neuronal plasticity needed for cognitive processes involving oscillatory patterns. WM stands to benefit significantly from this approach, given its well-defined electrophysiological oscillations. Therefore, tACS could potentially boost WM in patients with neurodegenerative diseases. METHODS: This study is a phase IIb randomised, double-blind clinical trial with a 3-month follow-up period. The study participants will be 62 participants diagnosed with MCI, aged over 60, from Valparaíso, Chile. Participants will receive an intervention combining twelve cognitive training sessions with tACS. Participants will receive either tACS or placebo stimulation in eight out of twelve training sessions. Sessions will occur twice weekly over 6 weeks. The primary outcomes will be electroencephalographic measurements through the prefrontal theta oscillatory activity, while the secondary effects will be cognitive assessments of WM. The participants will be evaluated before, immediately after, and 3 months after the end of the intervention. DISCUSSION: The outcomes of this trial will add empirical evidence about the benefits and feasibility of an intervention that combines cognitive training with non-invasive brain stimulation. The objective is to contribute tools for optimal cognitive treatment in patients with MCI. To enhance WM capacity, postpone the impairment of functionality, and obtain a better quality of life. TRIAL REGISTRATION: ClinicalTrials.gov NCT05291208. Registered on 28 February 2022. ISRCTN87597719 retrospectively registered on 15 September 2023.
Subject(s)
Cognitive Dysfunction , Quality of Life , Humans , Middle Aged , Aged , Chile , Cognitive Training , Treatment Outcome , Brain , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/therapy , Cognition/physiology , Randomized Controlled Trials as TopicABSTRACT
Patients recovering from COVID-19 commonly exhibit cognitive and brain alterations, yet the specific neuropathological mechanisms and risk factors underlying these alterations remain elusive. Given the significant global incidence of COVID-19, identifying factors that can distinguish individuals at risk of developing brain alterations is crucial for prioritizing follow-up care. Here, we report findings from a sample of patients consisting of 73 adults with a mild to moderate SARS-CoV-2 infection without signs of respiratory failure and 27 with infections attributed to other agents and no history of COVID-19. The participants underwent cognitive screening, a decision-making task, and MRI evaluations. We assessed for the presence of anosmia and the requirement for hospitalization. Groups did not differ in age or cognitive performance. Patients who presented with anosmia exhibited more impulsive alternative changes after a shift in probabilities (r = - 0.26, p = 0.001), while patients who required hospitalization showed more perseverative choices (r = 0.25, p = 0.003). Anosmia correlated with brain measures, including decreased functional activity during the decision-making task, thinning of cortical thickness in parietal regions, and loss of white matter integrity. Hence, anosmia could be a factor to be considered when identifying at-risk populations for follow-up.
Subject(s)
Anosmia , Brain , COVID-19 , Magnetic Resonance Imaging , SARS-CoV-2 , Humans , COVID-19/complications , COVID-19/psychology , COVID-19/physiopathology , COVID-19/diagnostic imaging , COVID-19/pathology , Anosmia/etiology , Anosmia/physiopathology , Male , Female , Middle Aged , Adult , Brain/diagnostic imaging , Brain/pathology , Brain/physiopathology , SARS-CoV-2/isolation & purification , Aged , Decision Making , Cognition/physiologyABSTRACT
Background: Addiction to online video game streaming has become one of the most appealing ways to occupy leisure time and is one of the most popular activities. The satisfaction it provides and the time invested in it are two of the main reasons why it is preferred. However, despite the clear benefits that this activity offers, in some cases, excessive use can lead to personal and/or family problems or abuse. Objective: The objective of the study was to develop and validate a scale to measure potential traits of dependence on online game streaming. The participants were 423 Peruvian adults aged between 18 and 47 years (M = 22.87, SD = 5.02). The Streaming Dependence Scale (SDS) was developed based on a literature review, and exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted. Results: The scale showed adequate internal consistency (α, CR, ω, and H > 80). Confirmatory analysis confirmed the one-dimensional structure (χ2 = 10.250, df = 5; p = 0.068; CFI = 0.98, TLI = 0.96, RMSEA = 0.06, SRMR = 0.05). Conclusion: The brief SDS is a valid and reliable measure that can be used as a useful tool to identify and evaluate streaming dependence.
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Pinus. ponderosa (P. Lawson and C. Lawson) is a commercial tree and one of the most important forest species in North America. Ponderosa pine suffers hardship when going through vegetative propagation and, in some cases, 15-30 years are needed to achieve full reproductive capacity. Based on previous works on P. ponderosa regeneration through in vitro organogenesis and trying to improve the published protocols, our objective was to analyze the influence of different types of explants, basal culture media, cytokinins, auxins, and light treatments on the success of shoot multiplication and rooting phases. Whole zygotic embryos and 44 µΜ 6-benzyladenine showed the best results in terms of explants survival. For shoot organogenesis, whole zygotic embryos and half LP (LP medium, Quoirin and Lepoivre, 1977, modified by Aitken-Christie et al., 1988) macronutrients were selected. A significant positive interaction between whole zygotic embryos and half LP macronutrients was found for the percentage of explants forming shoots. Regarding the light treatments applied, a significantly higher percentage of shoots elongated enough to be rooted was detected in shoots growing under blue LED at a light intensity of 61.09 µmol m-2 s-1. However, the acclimatization percentage was higher in shoots previously cultivated under fluorescent light at a light intensity of 61.71 µmol m-2 s-1. Anatomical studies using light microscopy and scanning electron microscopy showed the light treatments promoted differences in anatomical aspects in in vitro shoots; needles of plantlets exposed to red and blue LEDs revealed less stomata compared with needles from plantlets exposed to fluorescent light.
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BACKGROUND: This article highlights the contributions made by historically Black colleges and universities (HBCUs) to the nursing profession, as well as the challenges faced by HBCUs as they make these important contributions. METHOD: This study uses a mixed-methods approach that includes historical, qualitative, and quantitative methods. RESULTS: This study includes an overview of the history of the contributions of HBCUs to nursing, how HBCU nursing programs collaborate with majority institutions, strategies for retaining and supporting African American nurses within the HBCU setting, and challenges that HBCU nursing programs face. CONCLUSION: HBCUs contribute to the mobility of Black nursing students through partnerships and high-impact retention strategies. [J Nurs Educ. 2020;59(2):76-82.].