Sistema Regional de Información
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The low fertility is one of the greatest problems in mare reproduction. Preovulatory follicle diameter could be used as estrus predictor. Methods: Forty-three mares, 550 ± 34 kg live weight, 6.00 ± 2.30 years old, and 4.42 ± 0.39 body condition score (CC), without reproductive or sanitary problems were used to study the evolution of follicle diameter (DF) during an estrus cycle. The estrus detection and measurement of DF were done daily, mares with DF > 38 mm were inseminated, pregnancy was tested 16 d post-insemination. Variables evaluated were estrus length (Dcelo) and estrus cycle (Dciclo); DF at 21 d (DF21), at start of estrus (DFcelo), and at artificial insemination (DFIA); corpora luteum diameter lúteo (DCL); and pregnancy rate (TP16). The fixed effects included in the model were age of mare, CC, Dcelo, Dciclo, number of follicles, time to estrus appearance after day 21 (Celoh), DFcelo, and DF21. The statistical analyses were carried out with the MIXED and GLIMMIX procedures of SAS. Results: Age (p £ 0.0221) and Dcelo (p £ 0.036) were significant for most of the variables analyzed. Mares 9-11 years old had the greatest Dciclo, DCL, and DF. DFcelo was significant (p £ 0.0056) for DCL and DF21; while DF21 was (p £ 0.0001) for Celoh, DFcelo, and DFIA. The follicle growth showed a cubic trend, with a reduction in growth rate days before ovulation. Conclusion: Age of mare, DF21, and DFcelo, help to predict estrus appearance. Knowledge of ovarian dynamics helps to breed mares at the right time.

Some of the fruits of the family Annonaceae are appreciated for their organoleptic, digestive, nutritional, dietary, medicinal, and industrial properties. Although there is information about the nutritional value of some species such as Annona muricata (soursop) and A. cherimola (cherimoya), others are noted for their medicinal properties and toxicity. However, the antioxidant and nutraceutical potential of most of them, such as that of A. purpurea (chincuya), is unknown. The objective of this research was to evaluate nutritional and nutraceutical quality (phenolic compounds, flavonoids, and ascorbic acid) of three species of Annonaceae: soursop, cherimoya and chincuya, as well as to determine the toxicity of methanolic extracts of pulp, peel, seeds, and leaves of these species through a bioassay with Artemia salina, in order to contribute to the scientific knowledge of species with nutraceutical and economic potential in Mexico. The cherimoya fruit presented the highest concentration of crude protein (1.89 %), carbohydrates (20.65 %), the highest values of minerals (Ca, P, Mg, Na, Fe and Zn), phenolic compounds (366.27 mg EAG 100 g-1 F.W.) and ascorbic acid (48.36 mg EAA 100 g-1 F.W.). ); according to Pearson's correlation, the highest antioxidant activity was associated with the content of phenolic compounds and ascorbic acid; soursop fruit was higher than the other two species in lipid (0.31 %) and flavonoid levels (10.13 mg EQ 100 g-1 F.W.). Finally, the chincuya and cherimoya seed extracts resulted extremely toxic (LC50 = 5.0 ppm), while the soursop pulp extract was classified as very toxic (LC50 = 67.5 ppm), according to the criteria reported in other investigations extremely toxic (LC50 ≤ 10 ppm) and very toxic (LC50 10 - 100 ppm) in A. salina.      

Nanomaterials are currently of great interest to science and technology due to their physical, chemical, and mechanical properties can be adjusted according to their dimensionality, which is reflected in an improvement in their performance when compared to bulk or larger scale materials. Another advantage of nanomaterials is that can adopt different morphologies depending on the manufacturing method used. Nowadays there are different techniques for manufacturing nanomaterials. In this work, the anodization technique was used to obtain CuOH nanorods, because, compared to other techniques, anodization does not require expensive equipment or highly complex systems. To obtain CuOH nanorods, an electrolytic cell was used, formed by copper foils at 99.9 % purity, 0.3 mm caliber, and 3 cm2 of surface as anode. A 6 mm diameter cylindrical graphite rod as cathode and a solution of potassium hydroxide (KOH) with a concentration of 1.5 M as electrolyte also was used. A total of 21 samples were fabricated using times of 2 to 8 minutes, by 1-minute increments. Only a couple of samples were studied by scanning electron microscopy (SEM) to identify the morphology in anodized sheets and 7 samples were studied by Raman spectroscopy. The presence of nanorods composed of nanowires was corroborated by SEM, it was identified that nanorods have around 10 µm length and that the thicknesses are 200 nm and 50 nm respectively. By Raman microscopy was determined that nanorods are composed of CuOH, and a clear trend was found at the increase in the intensity of the Raman signals associated with CuOH as the anodization time increases. The reliability of use anodization technique for the manufacture of CuOH nanorods was demonstrated by means of the analysis carried out by Raman spectroscopy, since intensities in Raman signals associated with CuOH increase as the anodization time increases, strongly binding the thickness of the anodized layer with the anodizing time even though relatively short anodizing times (2-8 minutes) were used.

Introduction: At the global and national level there is concern about the constant increase in the consumption of legal and illegal drugs among young people, including university students. The use and abuse of legal and illegal drugs and art have traditionally been associated, however, there is little scientific evidence about this association in university students. Therefore, the purpose of this article was to analyze the consumption of legal and illegal drugs in students enrolled in the academic area of ​​arts at a public university in Mexico. Method: The study design was cross-sectional. The source of information was the database derived from the questionnaire for Drug Use in University Students (CODEU-2) used in the Second Diagnoses of Perception, risk and drug use in university students carried out in a public university in the State of Veracruz, Mexico. This questionnaire was applied online on the LimeSurvay platform to students of all periods / semesters. To identify the differences between variables, the Fisher’s exact test and chi-square were used, a significance level of 0.05 was considered. In addition, a multiple correspondence analysis was carried out to characterize students who consume legal and illegal drugs. Results: The analysis of the consumption of illegal drugs in the last twelve months showed that 30.7 % of the Arts students had used marijuana, 9.4 % medical drugs without a prescription, 6.8 % hallucinogens, 4.2% cocaine, and 3.6% methamphetamines. Regarding the consumption of legal drugs, the AUDIT test showed that 62.21 % presented low risk consumption, 20.35 % moderate risk consumption, 2.91 % high risk, and 2.32% very high risk. Regarding the problematic consumption of marijuana, 41.84 % showed low risk consumption, 12.27 % moderate risk and 5.10 % high risk. In the multiple correspondence analysis, four groups were identified for students who consumed legal drugs, and in the consumption of illegal drugs, three groups were formed. Discussion: Drug use in Arts students is worrying. It is recommended to develop more and better preventive strategies aimed at young people characterized by the vocation and need to be creative.

The objective of the study was the psychometric validation of a scale of own elaboration for the measurement of the perspectives of undergraduate students on the competences, training requirements, infrastructure, and human capital that the state of Tabasco, Mexico, requires for recovery of post-COVID-19 economic activity. Data was collected anonymously online, and each participant provided informed consent at the beginning of the questionnaire. A subsample of 368 students was selected. An exploratory factor analysis (EFA) was performed, using the factor extraction method by maximum likelihood with direct Oblimin rotation, reporting factor loadings greater than 0.5, thus meeting the minimum criteria to maintain all items. To validate the theoretical model, a Confirmatory Factor Analysis (CFA) was carried out, which allowed us to demonstrate the validity of the previously obtained structure. The model fit indicators (SRMR, AGFI, RMSEA, TLI, and CFI) were calculated, for which satisfactory values were obtained. The measurement model confirms the theoretical structure through the main adjustment indicators of both the exploratory and confirmatory factor analysis. The results present a contribution to the study of the rehabilitation process of economic activities after the COVID-19 pandemic. From a methodological perspective, it provides a solid and reliable diagnostic tool for the development of regional economic recovery programs.

In this paper a long-term portfolio optimization model is developed, through the use of economic indicators (CLI and BCI). In this way, an investment portfolio will adjust to the movements of the business cycle, mitigating its risk in the event of possible downturns. The proposed model was tested in Mexico between 1998-2021. The active strategy makes investments in fixed income (Certificados de la Tesorería, CETES) and the market index (Índice de Precios y Cotizaciones, IPC), through operations of 25 % of the capital in monthly decisions. The dynamic investment strategy outperforms market index by 4.3 % in the period analyzed (differences in annual geometric return). In that period, only 5 % of the annual returns of the active strategy were negative, compared to 25.8 % in the market index.

Jackfruit (Artocarpus heterophyllus Lam.) is a climacteric fruit whit a high commercial value, but susceptible to decay. The most important pathogens for jackfruit R. stolonifer and C. gloeosporioides may interact in different ways. The objectives of this study were to examine the interaction between three fungal species isolated from jackfruit and describe their behavior and interactions as a function of temperature. Three pathogen isolates from jackfruit rots, cultivated individually or paired at 4 cm in a natural medium were used. The growth rate was evaluated at 13, 25, and 35 °C. The Baranyi-Roberts model was used to obtain the radial growth rate. Differences between the growth rate of each fungus are the reference to determine the type of interaction. The effect of temperature of the unpaired isolates was studied by Rosso-Robinson’s model. The experiment was validated by infecting fresh jackfruit whit a mix of spores of all isolates. Rhizopus stolonifer is capable of rapidly colonizing the Petri dish thus reducing the space for the other fungi. The growth rates of unpaired and paired fungal isolates were statistically different showing that interactions between them exist. Rhizopus intermingling the others at 13 and 25 °C whereas, at the same temperatures, Colletotrichum AhCx-02 dominates AhCx-03. In contrast, dominance patterns of the Colletotrichum AhCx-03 strain were higher at 35 °C.        

The body weight of the ewes indirectly reflects their size and body composition. Its knowledge at the beginning of a reproductive and productive process can be of great value in determining the future productivity of the ewes. The aim of this study was to determine the effect of the body weight and the zoometric measurements of Blackbelly x Pelibuey yearling ewes at the beginning of mating on their productive and reproductive efficiency in their first two productive cycles. The productive and reproductive records of 26 ewes fed based on grazing and food supplementation were used. The study factor was the body weight category of yearling ewes (light, 20.3 kg; 59 % of body weight multiparous ewes; n = 13 and medium 24.3 kg; 70 % of body weight multiparous ewes; n = 13). The response variables were: body weight, daily weight gain, number of lambs and litter weight (at birth and weaning); reproductive parameters related to conception, gestation duration and lambing and total kilograms of lamb at weaning and gross income (MEX $) from the sale of total kilograms of lamb at weaning in the first two production cycles. The body weight category of ewes affected the change in body weight and daily weight gain during breeding (P < 0.05), as well as the weight of the litter at weaning during the first lactation and the intervals between mating and first estrus, mating, and conception, first lambing at conception, and between the first and second lambing (P < 0.05). During the second production cycle, the productive efficiency of the ewes was not affected by the body weight category (P > 0.05). The body weight category with which the ewes start their first breeding affected the reproductive and productive efficiency during the first breeding and first productive cycle. The productive efficiency of the ewes was not affected by the body weight category during the second production cycle. Higher body weight and body size in ewes allowed fewer days to manifest estrus and achieve conception in the first breeding; likewise, it favored the production of litters at weaning with greater weight in the first lactation, but not in the second. However, the total kilograms of lamb at weaning during the first two production cycles was higher in medium ewes compared to light ewes.

Introduction: The main research purpose is the identification of the Key Success Factors (KSF) for Social Impact Startups (SST) and how they face an emergency context (like COVID-19 pandemic) under female management as Business Model Innovation (BMI) design to the next normal Methodology: This research applies a known KSF for the author's SST proposal framework published in 2021, composed of 6 factors and 30 variables. Hence, this work is extension research, but now, from the female management point of view. The survey data was on 400 Mexican social startup CEO as survivors in the 2020 second half. Fuzzy set Qualitative Comparative Analysis (fsQCA) extracts different outcomes to get the same solution as KSF for SST under female management. Results: The entrepreneurship profile factor is considered a core condition for male and female management. However, as gender-based features, Key Performance Indicators (KPF) are absent for male management, and Strategic Analysis is absent (STA) for female management as KSF for SST. The research's main value is the female management's characterization as business model innovation design to the next normal. Conclusion: There are subtle differences among gender management as KSF for SST that implying opportunities to take advantage of gender-based features as Business Model Innovation (BMI). The relationship KSF-SST for BMI in the case of female management needs to develop the factors Strategic Analysis (STA); Business Plan (BPL); Market Knowledge (MKK), Key Performance Indicators (KPI), and Value Proposition (VPN). Male management, for another side, the Key Performance Indicators (KPI); Strategic Analysis (STA); Business Plan (BPL), and Market Knowledge (MKK). For both cases, the Entrepreneur Profile (EPR) is strongly present («core condition»), and additionally (VPN) for male management.

The aim of the study was to evaluate the effect of body condition score (BCS) at lambing over the resumption of ovarian and estrous postpartum activity in lactating Pelibuey ewes. Twenty ewes were assigned to two groups, according to the BCS at lambing: Low BCS (LBC, n = 10) and High BCS (HBC, n = 10). Ovarian and estrous activities were daily monitored from day 3 postpartum until the first estrous or 90 days postpartum. Continuous variables were analyzed using Student´s t test and binary responses with the exact Fisher test. No significant effect of BCS at lambing on ewes in estrous, lambing to first estrous interval, estrous length, and estrous cycle length, preovulatory follicles at estrous, the maximum follicular diameter at estrous day or ovulation rate was observed. However, the lambing to first preovulatory follicle interval was shorter in the HBC group (HBC = 6.2 ± 2.6 vs LBC = 10.8 ± 4.5 d; P < 0.05). The lambing to first corpus luteum intervals were similar between groups, but without estrous expression. The function of the first corpus luteum postpartum was similar in both groups. BCS at lambing did not affect the resumption of ovarian and estrous activity postpartum in lactating Pelibuey ewes.