Equal Opportunities to Access the University in Chile? An Application with a Spatial Heckman Probit Model

This study contributes to the debate on accessibility of higher education in Chile, focusing on both socioeconomic and geospatial dimensions of access to university study. The central question we address in this paper is the following: Does geography (physical distance and neighborhood effects) play a significant role in determining accessibility of higher education in Chile? We use Heckman probit-type (Heckit) models to adjust for selection in the process of completing the trajectory towards higher education – that is, pre-selection, application to study at university, and ultimately admission (or denial) to a higher education institution. The results shows that the geospatial elements have a significant local effect on the student’s application and access to Chilean universities.

Equal Opportunities to Access the University in Chile? An Application with a Spatial Heckman Probit Model

This study contributes to the debate on accessibility of higher education in Chile, focusing on both socioeconomic and geospatial dimensions of access to university study. The central question we address in this paper is the following: Does geography (physical distance and neighborhood effects) play a significant role in determining accessibility of higher education in Chile? We use Heckman probit-type (Heckit) models to adjust for selection in the process of completing the trajectory towards higher education – that is, pre-selection, application to study at university, and ultimately admission (or denial) to a higher education institution. The results shows that the geospatial elements have a significant local effect on the student’s application and access to Chilean universities.

CATIONIC NATURE OF WATER AND HYDROGEN PEROXIDE ON THE FORMATION OF PASSION FRUIT SEEDLINGS1

ABSTRACT This study was carried out with the objective of evaluating the water relations, photosynthetic pigments and growth of passion fruit cv. BRS Rubi do Cerrado, as a function of the cationic nature of irrigation water and exogenous application of hydrogen peroxide. The experiment was carried out under greenhouse conditions in Pombal – PB, Brazil. The experimental design was randomized blocks, in a 6 × 4 factorial scheme, corresponding to six cationic nature of water - CNW (S1 - Control; S2 - Na+; S3 - Ca2+; S4 - Na++Ca2+; S5 - Mg2+ and S6 - Na++Ca2++Mg2+) and four concentrations of hydrogen peroxide - H2O2 (0, 20, 40 and 60 μM), distributed in a randomized block design with four replicates. Plants in the control treatment (S1) were irrigated using water with electrical conductivity (ECw) of 0.3 dS m-1, while those of the other treatments (S2; S3; S4; S5 and S6) were subjected to ECw of 3.0 dS m-1, prepared with different cation(s). Application of 60 μM of H2O2 reduced the percentage of intercellular electrolyte leakage in plants irrigated with water of calcic composition. Salinity of water composed of sodium, sodium+calcium and sodium+calcium+magnesium, and H2O2 concentrations of 40 and 60 μM resulted in lower leaf water potential. The biomass accumulation of passion fruit was more sensitive to the variation of the electrical conductivity of the water. Regardless of the cationic nature, the use of water with electrical conductivity of 3.0 dS m-1 produced passion fruit seedlings with a Dickson quality index higher than 0.2, considered acceptable.

Effect of Phenol Application Time in the Treatment of Onychocryptosis: A Randomized Double-Blind Clinical Trial

Background: In the treatment of Onychocryptosis, chemical matricectomy with 88% phenol solution is one of the most common surgical procedures due to a recurrence rate of less than 5%, but it may produce a delay in healing time. The objective was to compare the healing time between phenol applications of 30 or 60 s. Methods: A comparative, prospective, parallel, randomized, and blinded clinical trial was registered with the European Clinical Trials Database. Twenty-seven patients (54 feet) with 108 affected nail folds were randomized and treated with chemical matricectomy with phenol. Each hallux was randomly assigned to one of two groups (60 vs. 30 s phenolization). Each patient and one investigator were blinded to the phenol application time in each foot. The outcome measurements were healing time, recurrence, pain, post-surgical bleeding, inflammation, and infection rate. Results: The 30 s application presents a shorter healing time (14.93 ± 2.81 days vs. 22.07 ± 3.16 days; p < 0.001) with a similar recurrence rate (p = 0.99). Post-operatory bleeding, pain, inflammation, and the infection rate did not show significant differences (p > 0.05). Conclusions: The 30 s phenol application time offers a shorter healing time than 60 s without affecting the effectiveness of the procedure, showing the same rate of complications.

Transcriptome and Proteome Conjoint Analysis Revealed That Exogenous Sulfur Regulates Glucosinolate Synthesis in Cabbage

Glucosinolates (GLS) are important anionic secondary metabolites that are rich in thiocyanin in cabbage, Brassica oleracea L. var. capitata. GLS are important in food flavor, plant antimicrobial activity, insect resistance, disease resistance, and human anti-cancer effects. Sulfur is an important raw material of GLS, directly affecting their synthesis. However, the mechanism of sulfur regulation of GLS biosynthesis in cabbage is unclear. In the present study, cabbage was treated with sulfur-free Hoagland nutrient solution (control; −S), and normal Hoagland nutrient solution (treatment; +S). Through joint transcriptomic and proteomic analyses, the effect of exogenous S on GLS synthesis was explored. S application induced GLS accumulation; especially, indole glycosides. Transcriptome analysis showed that +S treatment correlated positively with differentially expressed genes and proteins involved in amino acid biosynthesis, carbon metabolism, and plant hormone signal transduction. Compared with −S treatment, the mRNA expression of GLS synthesis genes (CYP, GSTU, UGT, and FMO) and those encoding transcription factors (RLK, MYB, AP2, bHLH, AUX/IAA, and WRKY) were upregulated significantly in the +S group. Combined transcriptome and proteome analysis suggested that the main pathway influenced by S during GLS synthesis in cabbage is amino acid biosynthesis. Moreover, S treatment activated GLS synthesis and accumulation.

Efficacy of a Topical Wound Agent Methanesulfonic Acid and Dimethylsulfoxide on In Vitro Biofilms

A topical desiccating wound agent containing methanesulfonic acid, dimethylsulfoxide and amorphous silica was evaluated in three in vitro models for its efficacy against biofilms produced by Pseudomonas aeruginosa (ATCC-15442) and Staphylococcus aureus (ATCC-6538). The in vitro biofilm models used were; the MBEC Assay®, Centre for Disease Control (CDC) Biofilm Reactor® and a Semi-solid biofilm model. A 30-s exposure of a topical wound desiccating agent was used in each model. A complete eradication of viable cells was demonstrated in all models for both strains (p < 0.0001). Imaging with scanning electron microscopy (SEM) was performed where possible. All three models demonstrated complete eradication of viable cells with a 30 s application of a topical wound desiccating agent.

Sulfur Regulates the Trade-Off Between Growth and Andrographolide Accumulation via Nitrogen Metabolism in Andrographis paniculata

Nitrogen (N) and sulfur (S) are essential mineral nutrients for plant growth and metabolism. Here, we investigated their interaction in plant growth and andrographolide accumulation in medicinal plant Andrographis paniculata grown at different N (4 and 8 mmol·L−1) and S concentration levels (0.1 and 2.4 mmol L−1). We found that increasing the S application rate enhanced the accumulation of andrographolide compounds (AGCs) in A. paniculata. Simultaneously, salicylic acid (SA) and gibberellic acid 4 (GA4) concentrations were increased but trehalose/trehalose 6-phosphate (Tre/Tre6P) concentrations were decreased by high S, suggesting that they were involved in the S-mediated accumulation of AGCs. However, S affected plant growth differentially at different N levels. Metabolite analysis revealed that high S induced increases in the tricarboxylic acid (TCA) cycle and photorespiration under low N conditions, which promoted N assimilation and S metabolism, and simultaneously increased carbohydrate consumption and inhibited plant growth. In contrast, high S reduced N and S concentrations in plants and promoted plant growth under high N conditions. Taken together, the results indicated that increasing the S application rate is an effective strategy to improve AGC accumulation in A. paniculata. Nevertheless, the interaction of N and S affected the trade-off between plant growth and AGC accumulation, in which N metabolism plays a key role.

Ethylene Supplementation Combined with Split Application of Nitrogen and Sulfur Protects Salt-Inhibited Photosynthesis through Optimization of Proline Metabolism and Antioxidant System in Mustard (Brassica juncea L.)

In the present study, the potential of ethylene as ethephon (an ethylene source) was investigated individually and in combination with split doses of nitrogen (N) and sulfur (S) soil treatments for removal of the damaging effects of salt stress (100 mM NaCl) in mustard (Brassica juncea L.). Plants were grown with 50 mg N plus 50 mg S kg−1 soil at sowing time and an equivalent dose at 20 days after sowing [N50 + S50]0d and 20d. Ethephon at 200 μL L‒1 was applied to combined split doses of N and S with or without NaCl. Plants subjected to NaCl showed a decrease in growth and photosynthetic characteristics as well as N and S assimilation, whereas proline metabolism and antioxidants increased. The application of ethephon to plants grown with split N and S doses significantly enhanced photosynthetic efficiency by increasing the assimilation of N and S, improving the concentration of proline and induction of the antioxidant system with or without NaCl. The regulation of ethylene and/or split forms of N and S application may be potential tools for not just overcoming salt stress effects in this species and in related Brassicaceae but also enhancing their photosynthesis and growth potential through increased nutrient assimilation.

Ethylene Supplementation Combined with Split Application of Nitrogen and Sulfur Protects Salt-Inhibited Photosynthesis through Optimization of Proline Metabolism and Antioxidant System in Mustard (Brassica juncea L.)

In the present study, the potential of ethylene as ethephon (an ethylene source) was investigated individually or with a combination of the split dosage of nitrogen (N) and sulfur (S) soil treatments for the removal of damaging effects of salt stress (100 mM NaCl) in mustard (Brassica juncea L.). Plants were grown with 50 mg N plus 50 mg S kg&minus;1 soil at sowing time and an equivalent dosage at 20 days after sowing ([N50 + S50]0d + [N50 + S50]20d). Ethephon at 200 &mu;L L‒1 was applied to combined split dosage of N and S with or without NaCl. Plants subjected to NaCl showed a deceased in growth and photosynthetic characteristics as well as N and S assimilation, though, proline metabolism and antioxidants increased. The application of ethephon to plants grown with split N and S dosages significantly enhanced the photosynthetic efficiency by increasing the assimilation of N and S, improving the content of proline and induction of the antioxidant system with or without NaCl. The regulation of ethylene and/or split form N and S application may be the potential tools for overcoming salt stress effects in this species and in related Brassicaceae.