Fear of COVID-19 associated with burnout syndrome in dentists of the Health Directorate of the National Police of Peru: a cross-sectional study at national level under multivariable regression model.

BACKGROUND: During the pandemic, many police dentists had the crucial responsibility of ensuring law and order while providing dental care by taking government-approved health measures to stop the spread of the coronavirus. The aim of this study was to assess the association between the fear of COVID-19 and Burnout syndrome in Peruvian dentists belonging to the Health Department of the National Police of Peru (PNP), taking into account possible confounding variables. METHODS: This cross-sectional and analytical study included 182 PNP dentists. The Fear COVID-19 Scale assessed fear of COVID-19 and the Maslach Burnout Inventory Test assessed burnout syndrome. The association between the fear of COVID-19 and Burnout syndrome (self-fulfilment) was analyzed using Spearman's Rho. A multivariable Poisson regression model with a robust variance estimation method was employed to evaluate the impact of fear of COVID-19 on the various dimensions of Burnout syndrome, considering possible confounding variables. The statistical significance level was set at p < 0.05. RESULTS: Under bivariate analysis, fear of COVID-19 was significantly linked with low direct intensity toward emotional exhaustion (Rho = 0.325, p < 0.001), very low direct intensity toward depersonalization (Rho = 0.180, p = 0.015), and very low inverse intensity toward self-fulfilment (Rho =-0.186, p = 0.012). Under multivariable analysis, it was observed that dentists who exhibited fear of COVID-19 were 3.4 and 3.7 times more likely to experience emotional exhaustion and depersonalization, respectively (APR = 3.40, 95% CI: 1.74-6.63 and APR = 3.68, 95% CI: 1.31-10.37), as compared to those who did not display fear of COVID-19. Moreover, none of the potential confounding factors were found to have a significant impact on emotional exhaustion (p > 0.05), depersonalization (p > 0.05), and self-fulfilment (p > 0.05). CONCLUSION: Fear of COVID-19 was significantly associated with emotional exhaustion and depersonalization, and inversely associated with self-fulfilment. PNP dentists who exhibited fear of COVID-19 were at greater risk for emotional exhaustion and depersonalization. In developing Burnout syndrome, no significant impact was observed from factors such as age, gender, marital status, children, hierarchy, years of service, work area, private practice, work over 40 h per week, type of service, work performed, sport practice and daily exercise time.

Factors associated with dental interns and professors perception of the management of disabled patients: A cross-sectional study under multivariable analysis.

Background: Patients with disabilities experience oral health inequalities, including increased disease prevalence and unmet healthcare needs. The aim of this study was to assess factors associated to the perceived management of patients with physical disabilities among dental interns and professors at a university located in the capital city and a branch in a province in Peru. Methods: This cross-sectional, observational, and analytical study included 100 dental interns and 75 Peruvian dental professors and was conducted from January to April 2022. A validated perception scale was used to evaluate the management of disabled patients. For the statistical analysis, the study employed Pearson's chi-square test and Fisher's exact test, along with a Poisson regression model that used robust variance. The adjusted prevalence ratio (APR) was utilized to evaluate perception while taking into account factors such as gender, age, marital status, origin, professional experience, previous treatment of a patient with physical disability, and previous cohabitation with a disabled patient. The significance level was set at p < 0.05. Results: The 86 % of dental interns and 88 % of dental professors had a poor perception of managing disabled patients, with no significant association between them (p = 0.698). Male and female dental interns displayed significant differences in perception (p = 0.004), while no other variables showed significant differences (p < 0.05). Conversely, dental professors displayed significant differences in all variables analyzed (p < 0.05). In dental interns, gender was found to be the only influential variable, with females having a 41 % higher likelihood of perceiving disabled patient management poorly compared to males (APR = 1.41; 95 % CI: 1.04-1.91) (p = 0.028). However, gender was not found to be a significant factor for dental professors (p = 0.449). Conclusion: The majority of dental interns and professors had a poor perception of managing disabled patients, with no significant differences observed between them. Moreover, gender significantly influenced the perception of managing patients with physical disabilities among dental interns specifically. On the other hand, neither age, marital status, origin, professional experience, previous treatment of a patient with physical disability, nor previous cohabitation with a disabled patient were found to be associated factors among dental interns and professors.

Restoring soil biodiversity.

Soil health is crucial for all terrestrial life, supporting, among other processes, food production, water purification and carbon sequestration. Soil biodiversity - the variety of life within soils - is key to these processes and thus key to soil restoration. Human activities that degrade ecosystems threaten soil biodiversity and associated ecosystem processes. Indeed, 75% of the world's soils are affected by degradation - a figure that could rise to 90% by 2050 if deforestation, overgrazing, urbanisation and other harmful practices persist. Restoring soil biodiversity is a prerequisite for planetary health, and it comes with many challenges and opportunities. Soil directly supports around 60% of all species on Earth, and land degradation poses a major problem for this biodiversity and the ecosystem services that sustain human populations. Indeed, 98% of human calories come from soil, and earthworms alone underpin 6.5% of the world's grain production. Moreover, the total carbon in terrestrial ecosystems is around 3,170 gigatons (1 gigaton (Gt) = 1 billion metric tons), of which approximately 80% (2,500 Gt) is found in soil. Therefore, restoring soil biodiversity is not just a human need but an ecological and Earth-system imperative. It is pivotal for maintaining ecosystem resilience, sustaining agricultural productivity and mitigating climate change impacts.

A 32-year global analyses on dynamic trends and geospatial visualization of genital tuberculosis and female infertility: A scientometric study.

Introduction: Genital tuberculosis (GT) is an infection that can affect the female reproductive system, including the uterus, cervix, and ovaries. Objective: To perform a scientometric exploration to analyze the spatiotemporal trend, evolution, and emerging patterns of scholarly output on GT and female infertility. Methods: An observational, descriptive, retrospective study employing a scientometric methodology was carried out. Metadata from scholarly articles spanning the years 1990-2022 were extracted from the Web of Science. The metadata from the chosen articles, totaling 172 manuscripts, were exported on May 17, 2023, in plain text format, which will allow the analysis and integration of the data in the software used. Results: We found at 111 sources and found 172 documents on tuberculosis and female infertility. We observed an average annual growth rate of 7.46 %, and the average age of the documents was 10.4 years. The dual overlay map showed the distribution of scientific publications on tuberculosis and female infertility. Journals on the left side of the map are cited mainly in the journals on the right. We found that Clinical Infectious Diseases and Lancet journals condensed patterns and trends in 1995, while the Indian Journal of Tuberculosis did so in 1996. Dheda K., Joubert JJ., and Wang Y. were the authors who had India, Iran, and China as their main affiliation, respectively, and they mainly published their studies in the "American Journal of Respiratory and Critical Care Medicine" and "Tropical Doctor," among others. Conclusions: This bibliometric study examined different sources and found an average annual growth rate of 7.46 %. Each article received an average of 16.48 citations. Different collaborative networks between countries were observed. In addition, there was a steady growth in published research in the field of tuberculosis and female infertility.

Sociodemographic Factors Associated with the Satisfaction Level of Peruvian Dental Students with Virtual Classes During the Covid-19 Pandemic: A Prospective Bicentric Study.

Background: The pandemic caused by Covid-19 impacted all areas of social, economic and educational activity. When there is a high risk of spreading highly infectious diseases, education is usually the first service to be suspended. The objective was to evaluate the sociodemographic factors associated with the satisfaction level of Peruvian dental students with virtual classes during the Covid-19 pandemic. Methods: This observational, cross-sectional, analytical study evaluated 237 dental students from the capital city and one Peruvian province using a validated 13-item questionnaire to measure the level of satisfaction with virtual classes. Pearson's chi-square test and a logit model were used to evaluate the associated factors such as age group, sex, marital status, monthly family income, area of residence, place of origin, occupation and computer use, considering a significance level of p<0.05. Results: Of all students, 50.6%, 40.1% and 9.3% presented a good, average and poor level of satisfaction, respectively, with the virtual classes received. In addition, those with a monthly family income of less than 500 US dollars were 3.15 times more likely to have poor satisfaction compared to those with a monthly family income of more than 1000 US dollars (AOR = 3.15; 95% CI: 1.23-8.05). The rest of the variables evaluated were not considered influential factors in the levels of satisfaction with the virtual classes received. Conclusión: Of all students, 50.6% and 9.3% reported good and poor satisfaction with virtual classes during the COVID-19 pandemic, respectively. Monthly family income of less than 500 US dollars was an influential factor. In addition, the variables age group, sex, marital status, area of residence, place of origin, occupation and computer use were not found to be influential factors.

Hydrodesulfurization of Dibenzothiophene: A Machine Learning Approach.

The hydrodesulfurization (HDS) process is widely used in the industry to eliminate sulfur compounds from fuels. However, removing dibenzothiophene (DBT) and its derivatives is a challenge. Here, the key aspects that affect the efficiency of catalysts in the HDS of DBT were investigated using machine learning (ML) algorithms. The conversion of DBT and selectivity was estimated by applying Lasso, Ridge, and Random Forest regression techniques. For the estimation of conversion of DBT, Random Forest and Lasso offer adequate predictions. At the same time, regularized regressions have similar outcomes, which are suitable for selectivity estimations. According to the regression coefficient, the structural parameters are essential predictors for selectivity, highlighting the pore size, and slab length. These properties can connect with aspects like the availability of active sites. The insights gained through ML techniques about the HDS catalysts agree with the interpretations of previous experimental reports.

Colorectal Cancer Screening Programs in Latin America: A Systematic Review and Meta-Analysis.

Importance: Colorectal cancer (CRC) is a leading cause of cancer-related mortality globally, with increasing incidence and mortality in Latin America. CRC screening programs can reduce disease burden, but information on screening programs in Latin America is limited. Objective: To describe characteristics (eg, type of program, uptake, neoplastic yield) of CRC screening programs in Latin America. Data Sources: PubMed, Ovid MEDLINE, EMBASE, Cochrane, PsycINFO, Web of Science Core Collection, LILACS, and SciELO were searched from inception to February 2023. Relevant references from bibliographies, conference proceedings, and gray literature were considered. The search strategy included English, Spanish, and Portuguese terms. Study Selection: Included were studies of CRC screening programs in Latin America using fecal immunochemical test (FIT) or colonoscopy as the primary screening method. Four reviewers independently assessed study eligibility based on titles, with review of abstracts and full texts as needed. Data Extraction and Synthesis: Guidelines from Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were followed for data abstraction and quality assessment. Descriptive information was extracted, and data were pooled using a random-effects model. Main outcomes and Measures: Program performance indicators included rates of participation and FIT positivity, adenoma detection rate (ADR), advanced adenoma detection rate (AADR), CRC detection rate, and colonoscopy quality indicators. Results: There were 17 studies included from upper middle-income and high-income countries in Latin America with a total of 123 929 participants. Thirteen studies used FIT as the initial screening method, whereas 4 used screening colonoscopy. The participation rate in FIT-based programs was 85.8% (95% CI, 78.5%-91.4%). FIT positivity rates were 15.2% (95% CI, 9.6%-21.8%) for the 50-ng/mL threshold and 9.7% (95% CI, 6.8%-13.0%) for the 100-ng/mL threshold. For FIT-based studies, the pooled ADR was 39.0% (95% CI, 29.3%-49.2%) and CRC detection rate was 4.9% (95% CI, 2.6%-7.9%); for screening colonoscopy-based studies, the pooled ADR was 19.9% (95% CI, 15.5%-24.8%) and CRC detection rate was 0.4% (95% CI, 0.1%-0.8%). Conclusions and Relevance: This systematic review and meta-analysis suggests that CRC screening in upper middle-income countries in Latin America is feasible, detecting rates of neoplasia comparable with those of high-income regions. Population-based screening programs should be developed or enhanced in these settings. There is a knowledge gap regarding feasibility and yield of screening programs in lower middle-income countries.

Sociodemographic factors associated with knowledge and attitudes of Peruvian dental interns about dental shade selection.

BACKGROUND: The dentist should have a thorough knowledge of the science, protocols and procedures for dental shade selection in order to mimic dental tissue with restorative materials, respecting the individual needs and attitudes of each patient and providing them with a pleasant and esthetically acceptable appearance. The present study evaluated the knowledge and attitudes of dental interns from two Peruvian universities about dental shade selection and its relationship with sociodemographic factors. METHODS: The present cross-sectional and analytical study was carried out on Peruvian dental interns from the Universidad Nacional Federico Villarreal and the Universidad Privada de San Juan Bautista during May to June 2022. Two validated questionnaires on knowledge and attitudes about dental shade selection were used. A Poisson regression model with robust variance using the adjusted prevalence ratio (APR) was used to assess the influence of the variables: age group, sex, place of origin and type of university, considering a significance level of p<0.05. RESULTS: The results showed that 40.8% (95% CI: 34.0% - 47.6%) of the interns presented unfavorable attitudes while 90.1% (95% CI: 86.0% - 94.2%) presented insufficient knowledge. It was also found that dental interns under 29 years of age were 32% less likely to have unfavorable attitudes (APR = 0.68, 95% CI 0.48 - 0.96) and 11% more likely to have insufficient knowledge (APR = 1.11, 95% CI 1.01 - 1.24) about tooth shade selection compared to dental interns aged 29 years and older. Finally, women were 55% more likely to have unfavorable attitudes about tooth shade selection compared to men (APR = 1.55; 95% CI: 1.08 - 2.22). CONCLUSION: The majority of dental interns presented insufficient knowledge and less than half had unfavorable attitudes about dental shade selection. In addition, being a student under 29 years of age was a risk factor for presenting insufficient knowledge and at the same time constituted a protective factor for presenting unfavorable attitudes. Likewise, being a female student was a risk factor for presenting unfavorable attitudes about dental shade selection.

Sociodemographic Factors Associated with Knowledge About Management of Cleft Lip and Palate Patients in Peruvian Dental Students: A Logistic Regression Analysis.

Background: Cleft lip and palate are relatively frequent craniofacial alterations caused by the lack of union of the frontonasal processes with the maxillary processes during the first weeks of intrauterine life. This study evaluated the sociodemographic factors associated with the level of knowledge about management of cleft lip and palate (CLP) patients in Peruvian dental students. Methods: This analytical, observational, cross-sectional and prospective study evaluated 191 dental students belonging to two branches of a private Peruvian university (one branch in the capital city and the other in a province), from September to November 2022. A validated questionnaire of 14 closed multiple-choice questions was used. A logit model was used to evaluate the influence of the variables: sex, age, academic year of study, marital status, relationship with CLP persons, place of origin and area of residence, on the level of knowledge of the students considering a significance level of p<0.05. Results: Of the total, 77%, 22.5% and 0.5% presented a poor, fair and good level of knowledge, respectively, on the dental management of the patient with cleft lip and palate. In addition, those who lived in urban areas were 2.8 times more likely to have poor knowledge about the dental management of patients with CLP, compared to those who lived in non-urban areas (OR = 2.83; 95% CI: 1.26-6.33). Finally, sex, age, marital status, place of origin, academic year of studies and relationship with CLP persons were not considered influential factors (p>0.05). Conclusion: Most of the students showed a poor level of knowledge about the dental management of patients with cleft lip and palate, a risk factor being that the students live in an urban area. It is recommended that educational authorities include selected topics on CLP in subjects related to infant, child and adolescent care.

Discovery of inhibitors of protein tyrosine phosphatase 1B contained in a natural products library from Mexican medicinal plants and fungi using a combination of enzymatic and in silico methods*.

This work aimed to discover protein tyrosine phosphatase 1B (PTP1B) inhibitors from a small molecule library of natural products (NPs) derived from selected Mexican medicinal plants and fungi to find new hits for developing antidiabetic drugs. The products showing similar IC50 values to ursolic acid (UA) (positive control, IC50 = 26.5) were considered hits. These compounds were canophyllol (1), 5-O-(ß-D-glucopyranosyl)-7-methoxy-3',4'-dihydroxy-4-phenylcoumarin (2), 3,4-dimethoxy-2,5-phenanthrenediol (3), masticadienonic acid (4), 4',5,6-trihydroxy-3',7-dimethoxyflavone (5), E/Z vermelhotin (6), tajixanthone hydrate (7), quercetin-3-O-(6″-benzoyl)-ß-D-galactoside (8), lichexanthone (9), melianodiol (10), and confusarin (11). According to the double-reciprocal plots, 1 was a non-competitive inhibitor, 3 a mixed-type, and 6 competitive. The chemical space analysis of the hits (IC50 < 100 µM) and compounds possessing activity (IC50 in the range of 100-1,000 µM) with the BIOFACQUIM library indicated that the active molecules are chemically diverse, covering most of the known Mexican NPs' chemical space. Finally, a structure-activity similarity (SAS) map was built using the Tanimoto similarity index and PTP1B absolute inhibitory activity, which allows the identification of seven scaffold hops, namely, compounds 3, 5, 6, 7, 8, 9, and 11. Canophyllol (1), on the other hand, is a true analog of UA since it is an SAR continuous zone of the SAS map.

Validation and characterization of a novel blood-brain barrier platform for investigating traumatic brain injury.

The Blood-Brain Barrier (BBB) is a highly-selective physiologic barrier responsible for maintaining cerebral homeostasis. Innovative in vitro models of the BBB are needed to provide useful insights into BBB function with CNS disorders like traumatic brain injury (TBI). TBI is a multidimensional and highly complex pathophysiological condition that requires intrinsic models to elucidate its mechanisms. Current models either lack fluidic shear stress, or neglect hemodynamic parameters important in recapitulating the human in vivo BBB phenotype. To address these limitations in the field, we developed a fluid dynamic novel platform which closely mimics these parameters. To validate our platform, Matrigel-coated Transwells were seeded with brain microvascular endothelial cells, both with and without co-cultured primary human astrocytes and bone-marrow mesenchymal stem cells. In this article we characterized BBB functional properties such as TEER and paracellular permeability. Our platform demonstrated physiologic relevant decreases in TEER in response to an ischemic environment, while directly measuring barrier fluid fluctuation. These recordings were followed with recovery, implying stability of the model. We also demonstrate that our dynamic platform is responsive to inflammatory and metabolic cues with resultant permeability coefficients. These results indicate that this novel dynamic platform will be a valuable tool for evaluating the recapitulating BBB function in vitro, screening potential novel therapeutics, and establishing a relevant paradigm to evaluate the pathophysiology of TBI.

Opportunities and challenges for microbiomics in ecosystem restoration.

Microbiomics is the science of characterizing microbial community structure, function, and dynamics. It has great potential to advance our understanding of plant-soil-microbe processes and interaction networks which can be applied to improve ecosystem restoration. However, microbiomics may be perceived as complex and the technology is not accessible to all. The opportunities of microbiomics in restoration ecology are considerable, but so are the practical challenges. Applying microbiomics in restoration must move beyond compositional assessments to incorporate tools to study the complexity of ecosystem recovery. Advances in metaomic tools provide unprecedented possibilities to aid restoration interventions. Moreover, complementary non-omic applications, such as microbial inoculants and biopriming, have the potential to improve restoration objectives by enhancing the establishment and health of vegetation communities.

Conceptual DFT, machine learning and molecular docking as tools for predicting LD50 toxicity of organothiophosphates.

CONTEXT: Several descriptors from conceptual density functional theory (cDFT) and the quantum theory of atoms in molecules (QTAIM) were utilized in Random Forest (RF), LASSO, Ridge, Elastic Net (EN), and Support Vector Machines (SVM) methods to predict the toxicity (LD50) of sixty-two organothiophosphate compounds. The A-RF-G1 and A-RF-G2 models were obtained using the RF method, yielding statistically significant parameters with good performance, as indicated by R2 values for the training set (R2Train) and R2 values for the test set (R2Test), around 0.90. METHODS: The molecular structure of all organothiophosphates was optimized via the range-separated hybrid functional ωB97XD with the 6-311 + + G** basis set. Seven hundred and eighty-seven descriptors have been processed using a variety of machine learning algorithms: RF LASSO, Ridge, EN and SVM to generate a predictive model. The properties were obtained with Multiwfn, AIMALL and VMD programs. Docking simulations were performed by using AutoDock 4.2 and LigPlot + programs. All the calculations in this work are carried out in Gaussian 16 program package.

Soil microbial community composition and functions are disrupted by fire and land use in a Mediterranean woodland.

The intersection of fire, land use transformations, and climate change is putting Mediterranean climate-type ecosystems at risk of soil degradation and loss of ecosystem services. Ondik et al. (2022b) showed that in a Mediterranean dry sclerophyll woodland of South Australia, high severity fire and clearing and grazing practices impacted both physicochemical and biological soil quality indicators. Building upon the work of Ondik et al. (2022b) this study aims to 1) identify soil physicochemical properties impacted by fire and land management that are indirect drivers of changes to soil microbial community composition and 2) determine whether the observed changes to soil microbial community composition affect soil microbial functions. Via a redundancy analysis, we identified fire and management-induced changes to pH, soil water repellency, nutrient stoichiometry, and total nutrient content as significant drivers of the composition of soil microbial communities. We then measured basal respiration, substrate induced respiration, and the carbon mineralisation quotient, and calculated functional trait distributions among microbial communities by linking 16S and 18S rRNA sequences to respiration modes and functional guilds, respectively. We found that fire reduced soil microbial respiration and the relative abundance (RA) of microbial symbionts, anaerobic bacteria, and microaerophilic bacteria, while increasing the RA of aerobic bacteria. Furthermore, management increased the RA of post-fire ectomycorrhizal fungi and may have reduced pathogenic load, microbial efficiency, and wood saprotrophs, while increasing litter, soil, and other saprotrophic species that are adapted to grasslands. This study shows that, through changes to microbial community composition, high severity wildfire and land management affected soil respiration rates, bacterial modes of respiration, prevalence of symbiotic bacteria and fungi, and microbial substrate preference. Having identified the main physicochemical drivers of changes to microbial community composition, we provide valuable insights into how fire and land management can impact soils in Mediterranean woodland.

Factors associated with the perception of university professors about academic dishonesty in dental students from two peruvian universities: analysis under multivariable regression model.

BACKGROUND: Academic dishonesty is an intentional behavior that transgresses ethics in the teaching-learning process. The present study aimed to evaluate the factors associated with the perception of university professors about academic dishonesty in dental students from two universities in the Peruvian capital. METHODS: This cross-sectional, analytical study evaluated 181 professors from two Peruvian universities between March and July 2022. A validated 28-item questionnaire was used to measure the perceived academic dishonesty of their students. A logit model was used to evaluate the influence of the variables gender, marital status, place of origin, academic degree, specialization, academic area, years of teaching experience, scientific publications, ethical training and university of origin, considering a significance level of p < 0.05. RESULTS: According to the median, professors perceived that their students sometimes had attitudes and motivations to commit academic dishonesty. The professors whose origin was the capital city were twice as likely to perceive dishonest attitudes in dental students as those whose origin was a province (OR = 2.04; 95% CI: 1.06-3.93). University professors in pre-clinical courses were 0.37 times less likely to perceive dishonest attitudes than those teaching in the dental clinic (OR = 0.37; CI: 0.15-0.91). University professors in basic science courses and professors in preclinical courses were 0.43 times (OR = 0.43; CI: 0.19-0.96) and 0.39 times (OR = 0.39; CI: 0.15-0.98) less likely to perceive dishonest motivations in their students compared to university professors in the dental clinic. Gender, marital status, academic degree, specialty, years of teaching experience, scientific publications and ethical training were not found to be influential factors (p > 0.05). CONCLUSION: Although all university professors surveyed perceived dishonest attitudes and motivations in their students, university professors from the capital city perceived such attitudes more. In addition, being a preclinical university professor was a hindered factor for perceiving such dishonest attitudes and motivations. It is advisable to implement and constantly disseminate regulations that empower academic integrity as well as to manage a system for reporting misconduct and to make students aware of the impact of dishonesty in their professional training.

Fire and land use impact soil properties in a Mediterranean dry sclerophyll woodland.

Fire directly impacts soil properties responsible for soil function and can result in soil degradation. Across the globe, climate change-induced droughts and elevated temperatures are exacerbating fire regime severity, breadth, and frequency, thus posing a threat to soil function and dependent ecosystem services. In Australia, the 2019-2020 fire season consumed nearly 50% of Kangaroo Island, South Australia, burning both dry sclerophyll woodland and adjacent historically cleared and grazed pastureland. Due to exacerbated fire regime elements, e.g., intensity and area affected, and interactions with historical land use, post-fire recovery of soil function was uncertain. This study assessed the impacts of a) the 2019-2020 fire event in Western River, Kangaroo Island on dry sclerophyll woodland and b) the interaction between this fire event and historical clearing and grazing on post-fire function of the soil. To do so, the following physicochemical and biological soil properties were analysed: labile active carbon, total carbon, total nitrogen, carbon to nitrogen ratio (C/N), pH, electrical conductivity, soil water repellency, aggregate stability, microbial community composition, and microbial diversity. Our results showed that the fire was of high severity, causing a reduction in nutrient content, an extreme rise in pH, and significant modifications to fungal communities in burnt compared to unburnt dry sclerophyll woodland. Furthermore, clearing and grazing raised post-fire soil nutrient levels and soil microbial diversity but reduced soil C/N and the abundance of ectomycorrhizal fungi in burnt pastureland compared to burnt woodland soils. This study highlights the role of management and fire severity in post-fire outcomes and emphasizes the need for comprehensive soil function assessments to evaluate the impacts of disturbance on soil. Taking direct measure of soil properties, as done here, will improve future assessments of fire season impacts and post-fire recovery in fire-prone landscapes.

QSTR Modeling to Find Relevant DFT Descriptors Related to the Toxicity of Carbamates.

Compounds containing carbamate moieties and their derivatives can generate serious public health threats and environmental problems due their high potential toxicity. In this study, a quantitative structure-toxicity relationship (QSTR) model has been developed by using one hundred seventy-eight carbamate derivatives whose toxicities in rats (oral administration) have been evaluated. The QSRT model was rigorously validated by using either tested or untested compounds falling within the applicability domain of the model. A structure-based evaluation by docking from a series of carbamates with acetylcholinesterase (AChE) was carried out. The toxicity of carbamates was predicted using physicochemical, structural, and quantum molecular descriptors employing a DFT approach. A statistical treatment was developed; the QSRT model showed a determination coefficient (R2) and a leave-one-out coefficient (Q2LOO) of 0.6584 and 0.6289, respectively.

Biocrust Amendments to Topsoils Facilitate Biocrust Restoration in a Post-mining Arid Environment.

Soil cryptogamic biocrusts provide many ecological functions in arid zone ecosystems, though their natural reestablishment in disturbed areas is slow. Accelerating reestablishment of biocrusts may facilitate the establishment of vascular plant communities within the timeframes of restoration targets (typically 5-15 years). One technique is to inoculate the soil surface using slurries of biocrust material harvested from another site. However, this is destructive to donor sites, and hence the potential to dilute slurries will govern the feasibility of this practice at large spatial scales. We conducted a replicated experiment on a disturbed mine site to test the individual and combined effects of two strategies for accelerating soil cryptogamic biocrust reestablishment: (1) slurry inoculation using biocrust material harvested from native vegetation; and (2) the use of psyllium husk powder as a source of mucilage to bind the soil surface, and to potentially provide a more cohesive substrate for biocrust development. The experiment comprised 90 experimental plots across six treatments, including different dilutions of the biocrust slurries and treatments with and without psyllium. Over 20 months, the reestablishing crust was dominated by cyanobacteria (including Tolypothrix distorta and Oculatella atacamensis), and these established more rapidly in the inoculated treatments than in the control treatments. The inoculated treatments also maintained this cover of cyanobacteria better through prolonged adverse conditions. The dilute biocrust slurry, at 1:100 of the biocrust in the remnant vegetation, performed as well as the 1:10 slurry, suggesting that strong dilution of biocrust slurry may improve the feasibility of using this technique at larger spatial scales. Psyllium husk powder did not improve biocrust development but helped to maintain a soil physical crust through hot, dry, and windy conditions, and so the potential longer-term advantages of psyllium need to be tested.

Protein tyrosine phosphatase 1B inhibitory activity of compounds from Justicia spicigera (Acanthaceae).

An infusion from the aerial parts of Justicia spicigera Schltdl., an herb commonly used to treat diabetes, inhibited the activity of protein tyrosine phosphatase 1B (PTP1B). Two undescribed compounds, 2-N-(p-coumaroyl)-3H-phenoxazin-3-one, and 3″-O-acetyl-kaempferitrin, along with kaempferitrin, kaempferol 7-O-α-L-rhamnopyranoside, perisbivalvine B and 2,5-dimethoxy-p-benzoquinone were isolated from the active extract. Their structures were elucidated by a combination of spectroscopic and spectrometric methods. The isolates were evaluated for their inhibitory activity against PTP1B; the most active compounds were 2-N-(p-coumaroyl)-3H-phenoxazin-3-one, and perisbivalvine B with IC50 values of 159.1 ± 0.02 µM and 106.6 ± 0.01 µM, respectively. However, perisbivalvine B was unstable. Kinetic analysis of 2-N-(p-coumaroyl)-3H-phenoxazin-3-one and 2,5-dimethoxy-p-benzoquinone (obtained in good amounts) indicated that both compounds behaved as parabolic competitive inhibitors and bind to the enzyme forming complexes with 1:1 and 1:2 stoichiometry. Docking of 2-N-(p-coumaroyl)-3H-phenoxazin-3-one and 2,5-dimethoxy-p-benzoquinone to PTP1B1-400 predicted a good affinity of these compounds for PTP1B catalytic site and demonstrated that the binding of a second ligand is sterically possible. The 1:2 complex was also supported by the second docking analysis, which predicted an important contribution of π-stacking interactions to the stability of these 1:2 complexes. Finally, an UHPLC-MS method was developed and validated to quantify the content of kaempferitrin in the infusion of the plant.