Dynamics of volatilomes emitted during cross-talking of plant-growth-promoting bacteria and the phytopathogen, Fusarium solani.

The dynamics of volatilomes emitted during the interaction between plant-growth-promoting bacteria (PGPB) and the phytopathogen Fusarium solani were evaluated for 5 days. The first screening was done to evaluate the antagonist activity of volatile compounds emitted by PGPB against F. solani. Volatilomes from 11 PGPB were determined individually and together with F. solani by using solid-phase microextraction coupled to gas-chromatography-mass spectrometry. Isolates of PGPB belonged to the Bacillus genus and inhibited from 18 to 24% the fungal mycelium growth. The isolates also induced morphological alterations of fungal hyphae, like small globular vesicles and the formation of chlamydospores, suggesting a stress mechanism response by the fungus. Volatilome profile showed 49 different compounds that appeared in the bacterial-fungal interaction, such as ketones, sesquiterpenes, monoterpenoids, alkanes, alkenes, carboxylic acids, and fatty acids. Some ketones and alcohols were detected in high abundance only in the interaction PGPB-fungus at 3 and 5 days. Bacillus circulans A19, Bacillus amyloliquefaciens A21, and Bacillus wiedmannii S18 shared a group of emitted alcohols and ketones when they were exposed to F. solani. F. solani produced its own volatilome profile, with the presence of sesquiterpenes, such as α-cubebene and caryophyllene, which increased significantly in co-incubation with the tested bacteria, suggesting chemical communication between them.

Optimizing cellulose fraction for enhanced utility: Comparative pre-treatment of Agave tequilana Weber var. blue bagasse fiber for sustainable applications.

In recent decades, natural fibers have emerged as an alternative to synthetic fibers due to their renewable nature, lower environmental impact, and comparable strength properties. Agave bagasse, a byproduct of agave juice extraction in Mexico, stands out for its potential in various industrial applications, notably biocomposite production. Bagasse is rich in cellulose, along with hemicellulose and lignin. Cellulose is the most suitable to be converted into valuable products, and it is versatile, renewable, and biodegradable. An effective pre-treatment is crucial to enrich its fraction. This study aims to determine the optimal pre-treatment conditions for the agave bagasse. Three different pre-treatments were tested, acid (H2SO4), enzymatic (Cellic® HTec2 enzymatic preparation), and sequence of acid-enzymatic (sulfuric acid and Cellic® HTec2), to determine which pre-treatment got the optimal cellulose fraction increase. The acid pre-treatment was conducted over three time ranges (5, 10, and 15 min) at different acid concentrations (1%, 1.5%, and 2%). Enzymatic reactions were conducted over 24 h, testing three different enzyme concentrations (1.5%, 3%, 4.5%). The sequential pre-treatment utilized the optimal conditions derived from the acid experiments (1.5% H2SO4 for 10 min), followed by enzymatic reactions carried out over three different durations (6, 12, and 24 h). The findings revealed that a 1.5% acid concentration applied for 10 min was the most efficient pre-treatment method. This pre-treatment resulted in a 1.9-fold increase in the cellulose fraction while reducing hemicellulose content by 30%. The hemicellulose reduction was confirmed through Fourier Transform IR spectroscopy (FTIR) analysis, complemented by scanning electron microscopy (SEM) observations highlighting physical alterations in the fiber structure. Furthermore, thermogravimetric analysis (TGA) demonstrated improved thermal stability, suggesting potential use in biocomposites. Future research should evaluate the environmental impact of optimized pre-treatment methods for agave bagasse.

Slow-release microencapsulates containing nanoliposomes for bioremediation of soil hydrocarbons contaminated.

Encapsulation and nutrient addition in bacterial formulations have disadvantages concerning cell viability during release, storage, and under field conditions. Then, the objective of this work was to encapsulate a bacterial consortium with hydrocarbon-degrading capacities in different matrices composed of cross-linked alginate/ polyvinyl alcohol /halloysite beads (M1, M2, and M3) containing nanoliposomes loaded with or without nutrients and evaluate their viability and release in a liquid medium, and soil (microcosmos). Also, evaluate their capacity to remove total petroleum hydrocarbons (TPH) for 165 days and matrices characterization. The encapsulate consortium showed a quick adaptation to contaminated soil and a percentage of removal (PR) of TPH up to 30% after seven days. All the matrices displayed a PR of up to 90% after 165 days. The matrix M2 displayed significant resistance to degradation and higher cell viability with a PR of 94%. This result supports the encapsulation of bacteria in a sustainable matrix supplemented with nutrients as a well-looked strategy for improving viability and survival and, therefore, enhancing their effectiveness in the remediation of hydrocarbon-contaminated soils.

Superconducting quantum critical point in CeCoIn(5-x)Sn(x).

We report a combined pressure-doping study in the nearly two-dimensional heavy fermion superconductor CeCoIn5 as its superconducting phase is driven to the normal state by Sn doping and/or applied pressure. Temperature-pressure-dependent electrical resistivity measurements were performed at the vicinity of a superconducting quantum critical point where Tc→0. A universal plot of the concentration- and pressure-dependent phase diagram suggests that for the concentrations studied a single mechanism is responsible for reducing Tc and bringing the system to the superconducting quantum critical point. A two-band model with hybridization controlled by pressure and doping provides a consistent description of the phase diagram and the suppression of the d-wave superconductivity in this material.

Volatile emission compounds from plant growth-promoting bacteria are responsible for the antifungal activity against F. solani.

The aims of this work were to screen isolated bacteria with a dual capacity: to inhibit Fusarium solani and to promote plant growth. Also, volatile compounds that would be responsible for that effect were identified. Seventy bacterial strains from the air, agricultural soils, hydrocarbons-contaminated soils, and extremophile soils were tested. The former were identified by Matrix-Assisted Laser Desorption/Ionization-time of flight mass spectrometry and 16S rDNA sequencing. The plant growth-promoting bacteria (PGPB) and their capability for phosphate solubilization, siderophores production, and indole production were determined. Twenty isolates from Bacillus and Pseudomonas genera inhibited the mycelial growth up to 40% in direct assays. Eleven isolates significantly inhibited mycelial growth in 18-24% via volatile emissions. Volatile compounds related to antifungal activity or stress response include ketones, sesquiterpenes, monoterpenoids, alkanes, and fatty acids. Our results support the potential of these PGPB to act as biocontrol agents against fungal pathogens via volatile emissions.

Dentinal tubules driven wetting of dentin: Cassie-Baxter modelling.

We investigate the wetting properties of dentin surfaces submitted to a phosphoric acid etching followed by an air drying procedure, as in clinical situations of adhesive dentistry. The surface topography of the etched surfaces was characterized by AFM, and the wetting properties of water on these rough and heterogeneous surfaces were studied, by contact angle measurements. We showed that the contact angle increases with the acid exposure time and consequently with both surface roughness and the organicmineral ratio of the dentin components. From the whole results, obtained on dentin and also on synthesized hydroxyapatites samples, we inferred a water contact angle of ~133° on the dentinal tubule. These experimental results may be described by the Cassie-Baxter approach, and it is suggested that small air pockets could be formed inside the dentinal tubules.

Dynamics of nitrogen in a PAHs contaminated soil amended with biosolid or vermicompost in the presence of earthworms.

Nitrogen mineralization in PAHs contaminated soil in presence of Eisenia fetida amended with biosolid or vermicompost was investigated. Sterilized and unsterilized soil was contaminated with PAHs, added with E. fetida and biosolid or vermicompost and incubated aerobically for 70 days, while dynamics of inorganic N were monitored. Addition of E. fetida to sterilized soil increased concentration of NH(4)(+) 100> mg N kg(-1), while concentrations in unsterilized remained <60 mg N kg(-1) except for soil amended with biosolid plus PAHs where it increased to >80 mg kg(-1). Addition of PAHs had no significant effect on concentration of NH(4)(+) compared to the unamended soil, except in the soil added with biosolid. Addition of E. fetida to sterilized soil increased concentration of NO(2)(-) 15> mg N kg(-1) while concentrations in unsterilized soil remained <7.5 mg N kg(-1) except for soil amended with biosolid where it increased to >20 mg kg(-1). Addition of PAHs had no significant effect on concentration of NO(2)(-) compared to the unamended soil. Addition of biosolid and vermicompost increased concentration of NO(3)(-), while addition of E. fetida decreased concentration of NO(3)(-) in biosolid amended soil. It was found that NH(4)(+) and NO(2)(-) oxidizers were present in the gut of E. fetida, but their activity was not sufficient enough to inhibit a temporarily increase in concentrations of NH(4)(+) and NO(2)(-). Contamination with PAHs induced immobilization of N in biosolid or vermicompost amended soil, as did feeding of E. fetida on biosolid or vermicompost.

Dissipation of polycyclic aromatic hydrocarbons from soil added with manure or vermicompost.

The dissipation of three PAHs, i.e., 500 mg phenanthrene kg(-1) soil, 350 mg anthracene kg(-1) soil and 150 mg benzo(a)pyrene kg(-1) soil, was investigated in soil from Acolman (México) added with cow manure or vermicompost while production of CO(2) and inorganic N was monitored. At day 0, recovery of added phenanthrene was 95%, anthracene 96% and benzo(a)pyrene 100% in sterilized soil and concentrations did not change significantly in sterilized soil over time. Application of organic material did not affect the concentration of phenanthrene and anthracene, which decreased sharply in the unsterilized soil in the first weeks of the incubation. Less than 3% of the added phenanthrene was detected after 100 days and less than 8.5% of the added anthracene (mean of the two experiments). The decrease in concentration of benzo(a)pyrene (BaP) was not fast as that of phenathrene and anthracene, and 22% was extractable from soil still after 100days. It was concluded that addition of farm yard manure (FYM) and vermicompost only had an effect on the initial dissipation of phenanthrene, anthracene and benzo(a)pyrene in soil of Acolman.

Utilization of vinasses as soil amendment: consequences and perspectives.

Vinasses are a residual liquid generated after the production of beverages, such as mezcal and tequila, from agave (Agave L.), sugarcane (Saccharum officinarum L.) or sugar beet (Beta vulgaris L.). These effluents have specific characteristics such as an acidic pH (from 3.9 to 5.1), a high chemical oxygen demand (50,000-95,000 mg L(-1)) and biological oxygen demand content (18,900-78,300 mg L(-1)), a high total solids content (79,000 and 37,500 mg L(-1)), high total volatile solids 79,000 and 82,222 mg L(-1), and K(+) (10-345 g L(-1)) content. Vinasses are most commonly discarded onto soil. Irrigation of soil with vinasses, however, may induce physical, chemical and biochemical changes and affect crop yields. Emission of greenhouse gases (GHG), such as carbon dioxide, nitrous oxide and methane, might increase from soils irrigated with vinasses. An estimation of GHG emission from soil irrigated with vinasses is given and discussed in this review.

Drop evaporation on superhydrophobic PTFE surfaces driven by contact line dynamics.

In the present study, we experimentally study the evaporation modes and kinetics of sessile drops of water on highly hydrophobic surfaces (contact angle ∼160°), heated to temperatures ranging between 40° and 70 °C. These surfaces were initially constructed by means of controlled tailoring of polytetrafluoroethylene (PTFE) substrates. The evaporation of droplets was observed to occur in three distinct phases, which were the same for the different substrate temperatures. The drops started to evaporate in the constant contact radius (CCR) mode, then switched to a more complex mode characterized by a set of stick-slip events accompanied by a decrease in contact angle, and finally shifted to a mixed mode in which the contact radius and contact angle decreased simultaneously until the drops had completely evaporated. It is shown that in the case of superhydrophobic surfaces, the energy barriers (per unit length) associated with the stick-slip motion of a drop ranges in the nJ m(-1) scale. Furthermore, analysis of the evaporation rates, determined from experimental data show that, even in the CCR mode, a linear relationship between V(2/3) and the evaporation time is verified. The values of the evaporation rate constants are found to be higher in the pinned contact line regime (the CCR mode) than in the moving contact line regime. This behavior is attributed to the drop's higher surface to volume ratio in the CCR mode.

Tequila vinasses acidogenesis in a UASB reactor with Clostridium predominance.

Tequila vinasses represent an acidic, highly concentrated pollutant effluent generated during the distillation step of Tequila production. Although acidogenesis of Tequila vinasses has been reported for some reactor configurations, a characterization of the bacteria present during this metabolic process is lacking in the literature. Hydraulic retention times (HRT) between 36 and 6 h and organic loading rates (OLR) from 5 to 30 g COD L(-1) d(-1) were assessed in a UASB reactor fed with Tequila vinasses. Results showed that OLR excerted a stronger effect (p ≤ 0.0001) on parameters such as gas production rate, pH, and acidity than HRT. While it was clear that shorter HRT were related to higher volatile fatty acid production levels. Figures above 2 Lgas Lreactor (-1) d(-1) (where "gas" could be a mixture of methane and hydrogen) were attained only with an OLR as high as 30 g COD L(-1) d(-1). Bacterial identification of a sludge sample at the end of the experiment revealed that acid-tolerant microorganisms that remained in the reactor were exclusively affiliated to the Clostridium genera, being the first report of organisms identification for Tequila vinasses acidogenesis. These findings are relevant to the field of biotechnology since acidogenesis of Tequila vinasses using identified and studied microorganism abilities (i.e. Clostridium strains) presents the opportunity of optimizing processes intended for different metabolites production (butanol, volatile fatty acids, hydrogen, solvents).

Molecular diagnosis of alkaptonuria mutation by analysis of homogentisate 1,2 dioxygenase mRNA from urine and blood.

Alkaptonuria (AKU) is caused by lack of homogentisate 1, 2 dioxygenase (HGO) activity. From the complete sequence of a human HGO cDNA, primers were designed in order to obtain reverse transcription-polymerase chain reaction products from tissues with ectopic transcription amenable to diagnostic analysis. A search for mutations in HGO cDNA was performed in an AKU family using urine and blood samples. The results show complete cosegregation (Z = 6.32; theta = 0) between a C-->T transition at position 817 of the human HGO cDNA and AKU. This mutation predicts a Pro-->Ser replacement at amino acid 230, and generates an EcoRV site.

Fos expression in female hamsters after various stimuli associated with mating.

Detection of the expression of c-fos mRNA or its protein product, Fos, has been used to indicate differences in neuronal response to exogenous stimuli. Factors contributing to differences in Fos expression as a result of various stimuli associated with mating have been extensively studied in the female rat. Less is known about the factors that contribute to Fos expression in female hamsters. Female hamsters differ from female rats in several aspects of sexual behavior; therefore, it seems likely that Fos expression may also differ. The purpose of this study was to determine which factors associated with mating selectively affect Fos expression in the female hamster. Animals were ovariectomized, hormone treated, and then exposed to several behavioral conditions. Fos expression in several brain areas was then assessed via immunocytochemistry (ICC). As has been found by others, mating increases Fos immunoreactivity in a number of brain regions. Specifically, vaginal-cervical stimulation (VCS) was determined to be the salient factor contributing to Fos expression in the preoptic area (POA) and bed nucleus of the stria terminalis (BNST) of ovariectomized hormone primed female hamsters that received a mating interaction.

Edema volume, not timing, is the key to success in lymphedema treatment.

BACKGROUND: There are currently between 1 and 2 million breast cancer survivors in the United States. Is the advocated, early intervention the key to successful treatment, or are there other, more important factors? METHODS: Responses to combined decongestive therapy (CDT) for 69 women were analyzed with regard to duration of lymphedema, differences in arm circumference, percent differences in arm volumes, volume of edema, reduction of edema volumes, and duration of treatment. RESULTS: Two- and three-dimensional (2D and 3D) analyses showed little correlation between duration and volume of edema or between duration and response and treatment. However, they did show a correlation between initial volumes of fluid in the tissues and responses. Patients with initial volumes of 250 mL or less had a mean reduction of 78% with CDT, whereas those with initial volumes between 250 and 500 mL had a mean reduction of 56%. CONCLUSION: The key to predicting successful lymphedema treatment is the initial volume of edema in the tissues regardless of whether the intervention is early or late.

Inexpensive, safe and simple nasoenteral intubation--an alternative for the cost conscious.

The efficacy and safety of nasoenteral feedings via small bore, flexible tubes have been extensively studied and reported. Most of the tubes currently used have similar characteristics including a high price ($7.00-$17.30 per tube). Our study using inexpensive ($0.55 each), polyvinyl pediatric feeding tubes and reusable guide wires in 21 patients shows that a weighted tip is not necessary for the passage of tubes into the duodenum (19/27 tubes passed) and that with proper nursing care and patient cooperation, the tubes can remain in place and patent for periods up to 71 days. The cost savings using the ubiquitous pediatric feeding tube and a reusable guide wire are significant (between $6.25 and $16.55 per tube used) and make this a more cost conscious alternative.

Non-X-linked hyperimmunoglobulin M syndrome with chronic interstitial pneumonitis.

Hyperimmunoglobulin M (IgM) syndrome is a rare primary immunodeficiency disorder, and the non-X-linked form of this syndrome is even more infrequent. We report the clinical case of a 6-year-old girl. Her disease began at the age of 1 year when she experienced bronchial obstruction. When she was 3 years old she developed severe recurrent respiratory infections of unusual clinical course. Serum IgM was elevated and the other serum immunoglobulins were absent. Cellular immune response was impaired, with severe depression of delayed hypersensitive cutaneous response and of proliferative response to mitogens. The CD40 ligand expression decreased. Chest CT scan showed areas of lung condensation, bronchial dilatation and signs suggesting interstitial pneumonitis. The latter was confirmed by a biopsy showing a high number of Langerhans' cells and an early-stage fibrosis. She was treated with antibiotics, inhaled bronchodilators and corticosteroids, intravenous immunoglobulin, chloroquine and prednisone. Despite the substitution therapy, her clinical course was slow, with respiratory infections and oxygen dependance. The follow-up thoracoscopic biopsy performed after 18 months of immunosuppressant therapy showed a progression of fibrosis and a decrease in the inflammatory infiltrate.

Wetting on nanorough surfaces.

We investigate the wetting properties of random nanostructured surfaces, with particular attention devoted to the phenomenon of contact angle hysteresis. For this purpose, solid substrates were initially tailored at a nanometric scale by using swift heavy ion irradiation which produced a random distribution of defects. We characterize the wetting properties of water on these heterogeneous surfaces by an average spreading parameter and by the contact angle hysteresis. For weak values of the areal density of defects phi(d), the hysteresis grows linearly with phi(d), indicating that the defects pin the contact line individually. However, at higher values of phi(d), collective pinning effects appear and the hysteresis decreases with increasing phi(d). We show that in the linear regime our experimental results are in good quantitative agreement with theoretical predictions for contact angle hysteresis induced by a single isolated defect on a solid surface.

Composting of tannery effluent with cow manure and wheat straw.

Wastewater from the leather industry in León (Guanajuato, México) is discharged into the Turbio river without treatment. Tannery wastewater contains utilizable nutrients, but also toxic organic compounds which might affect soil processes and plant growth, and pathogens, which might pose a threat to the local farming community. Tannery effluent was composted with cow manure and wheat straw for 90 days to reduce pathogens and toxic organic compounds and monitored. The compost was characterized by an electrolytic conductivity (EC) of 28.1 ms cm(-1), cation exchange capacity of 17.7 meq 100 g(-1), an absorbance at 645 nm of 0.0175, a respiration rate of 0.062 mg CO2-C kg(-1) compost-C day(-1), pH 8.5 and C:N ratio 7:1 with a germination index for cress (Lepidium sativum) of 48% after 90 days. Less than 10 faecal coliforms and no Salmonella sp., Shigella sp. or eggs of helminthes were detected in the compost while total coliforms decreased by log10 of 2. Total concentrations of lead (Pb) were 8.9 mgkg(-1) dry compost, chromium (Cr) 77 mg kg(-1) dry compost, cadmium (Cd) 0.4 mg kg(-1) dry compost, copper (Cu) 10.3 mg kg(-1) dry compost and sodium (Na) 14,377 mg kg(-1) dry compost. The compost characteristics indicated that it was mature, but the germination index for cress of less than 50% suggested possible remaining phytotoxic compounds. However, the large salt concentrations (especially Na), might have inhibited cress development and thus reduced the germination index. The large salt concentration might thus limit the use of this kind of compost.

Free falls from heights: a persistent urban problem.

In order to determine the significance and implications of falls from heights in the North Central Bronx Hospital (NCBH) patient population area, the records of 203 patients who fell from heights of 5 to 72 feet and who died or were admitted to NCBH over a five-year-period were reviewed. Demographic and clinical data were collected and analyzed for 192 of those patients. The findings show a male-to-female ratio of two to one, an age range of four months to 86 years, and a disproportionately high incidence of falls among minority group children.Seventy-six percent of patients had skeletal, 12 percent abdominal, and 10 percent skull fractures and cerebral edema. Twenty-two percent of juveniles (0 to 17 years) and 5 percent of adults had craniocerebral trauma. Thirty-one percent required surgery. Ten percent of the admitted patients had permanent disabilities. A trauma scoring system, the Injury Severity Score, correlated directly with height fallen. Overall mortality was 28 percent but only 6.6 percent in the juvenile group. Most of the falls were accidental (45 percent) or suicide attempts (22 percent).Although recognized as a health problem at least since 1965, falls from heights continue to be a cause of morbidity and mortality in urban people 20 years later. Renewed efforts at education and the passage and enforcement of public health laws are needed if their numbers are to be decreased.

Predictors of preclinical and clinical performance of minority medical students.

Although several studies have examined the relationship between minority students' admissions profiles and performance in the preclinical curriculum, there is a dearth of information about the ability of admissions variables to predict performance in the clerkships and on National Boards, Part II. Consistent with other research, a study of 59 minority students at the Albert Einstein College of Medicine found that the Medical College Aptitude Test (MCAT) chemistry score is the most consistent predictor of performance on internal examinations in years 1 and 2, and on National Boards, Part I. On the Part II examination, however, the only significant correlation is with the MCAT reading score, while the MCAT quantitative score and the recommendation of the premedical advisor are the best predictors of clerkship grades. Since students' mean MCATs and grade point averages (GPAs) are similar to those of all minority students accepted to medical schools in 1982, these findings may be generalized to that larger population.