Purpose: Currently, information on the psychometric properties of the Medical outcomes study-social support survey (MOS-SSS) for patients with chronic disease in primary health care, suggests problems in the dimensionality, specifically predominant unidimensionality in a multidimensional measure. The aim of this study was to determine the internal structure (dimensionality, measurement invariance and reliability) and association with other variables.Methods: A total of 470 patients with chronic disease from a Family Medicine Unit at the Instituto Mexicano del Seguro Social, IMSS, with a mean age of 51.51 years were included. Participants responded to the Questionnaire of Sociodemographic Variables (Q-SV), SF-36 Health-Related Quality of Life Scale–version 1.1, and MOS-SSS.Results: Non-parametric (Mokken scaling analysis) and parametric (confirmatory factor analysis) analyses indicated unidimensionality, and three-factor model was not representative. A new 8-item version (MOS-S) was developed, where measurement invariance, equivalence with the long version, reliability, and relationship with the SF-36 were satisfactory.Conclusion: The MOS-SSS scale is unidimensional, and the shortened version yields valid and reliable scores for measuring social support in patients with chronic disease at the primary health care.

There is evidence in the literature that anonymity when investigating individual variables could increase the objectivity of the measurement of some psychosocial constructs. However, there is a significant gap in the literature on the theoretical and methodological usefulness of simultaneously assessing the same measurement instrument across two groups, with one group remaining anonymous and a second group revealing identities using names. Therefore, the aim of this study was to compare the psychometric characteristics of a measure of depressive symptoms in two groups of adolescents as a consequence of identification or anonymity at the time of answering the measuring instrument. The participants were 189 adolescents from Metropolitan Lima; classrooms were randomly assigned to the identified group (n = 89; application requesting to write one’s own name) or to the anonymous group (n = 100; application under usual conditions), who responded to the Childhood Depression Inventory, short version (CDI-S). Univariate characteristics (mean, dispersion, distribution), dimensionality, reliability, and measurement invariance were analyzed. Specific results in each of the statistical and psychometric aspects evaluated indicated strong psychometric similarity. The practical and ethical implications of the present results for professional and research activity are discussed.

The prediction of fuel load areas and species associated with these events reduces the response time to fight forest fires. The objective of this study was to estimate the annual fuel load from 2009–2013, predict the annual fuel load in the rest of the ecosystem, identify species that contribute most to this load and compare the percentage of area by risk category in the temperate forests of Tamaulipas. Fuel load was estimated with inventory data using three models. Fuel load was predicted with elevation, total annual precipitation, mean annual temperature, and enhanced vegetation index from satellite scenes using partial least squares regression. The highest concentration of fuel load was associated with the oak, oak-pine, pine forest and mountain mesophyll forest ecosystems. The contribution of genera to fuel load was different. Quercus contributed the most variation among clusters, and the contribution among Quercus species was similar. The results highlight the importance of focusing fuel management programs on this type of ecosystem, emphasizing actions in particular Quercus, and the results can also serve as a basis for future research, such as carbon sequestration and forest management programs.

En la modelación de la relación longitud-peso (RLP) en tiburones siempre se ha ajustado el modelo potencial [modelo lineal (L) en versión logarítmica], nunca se ha aplicado la inferencia multimodelo (IMM) y siempre se ha asumido un crecimiento constante en todas las fases del desarrollo ontogénico. El tiburón martillo cabeza de pala (Sphyrna tiburo) del Golfo de México, no es la excepción. Mediante la modelación de la RLP en hembras (H), machos (M) y sexos combinados (C) de S. tiburo, y aplicando la IMM [modelos (L), cuadrático, cúbico, broken-stick (BS), dos segmentos (DS), BS y DS con transición logística entre segmentos] basada en la teoría de la información (TI), se probó la hipótesis de que el ajuste de L es insuficiente para describir la RLP en tiburones. Ningún modelo fue seleccionado con un peso de evidencia a su favor (wi%) mayor al 90%. La IMM evidenció un ajuste insuficiente en L (wi% = 0,86, 72,70 y 0,45%, en H, M y C, respectivamente), y significativo en el modelo promedio (wi%= 99,14, 27,30 y 99,55%, en H, M y C respectivamente); y demostró que el crecimiento cambia en función de la talla y presenta un marcado cambio morfológico en cierta talla específica, manifestado por los tres tipos de crecimiento registrados en H y C [alométrico negativo (CAN) y positivo (CAP), y crecimiento isométrico (CI)], y los dos en M (CI y CAP), cuyos cambios entre tipos de crecimiento fueron coincidentes con el cambio de dieta juvenil-adulto y el inicio de la madurez sexual, reportados por la literatura.

Artisanal fisheries in Mexico frequently operate with limited data, lacking historical catch and effort series. In this context, the population status of the dogfish (Rhizoprionodon terraenovae) was evaluated for the first time in Priority Marine Regions 45–46 and the area of influence of the Wetland of International Importance Playa Tortuguera Rancho Nuevo, Tamaulipas, using methods based on size frequencies. Between November 2018 and February 2020, 541 artisanal fishing organisms were analyzed in La Barra del Tordo using FISAT II. The von Bertalanffy growth parameters for combined sexes were: L∞ = 105 cm, k = 0.59 years⁻¹, t₀ = −0.195 years. Total (Z), natural (M) and fishing (F) mortalities were 4.13, 0.467 and 3.22 years⁻¹, respectively. The average exploitation rate (E = F/Z) was 0.78 (95% CI: 0.745–0.805), exceeding the reference point of 0.5 indicating severe overexploitation. The parameters showed biological consistency (Ø′ = 3.81; M/k = 0.79), and natural mortality was within the range reported for the species. This finding, in a priority region for conservation under the regime of the Conservation Sector of the Marine Ecological Management Program, shows the urgent need to implement fisheries management with an ecosystem approach that guarantees the sustainability of the fishery and the integrity of the coastal ecosystem. The study demonstrates that, even with limited data, it is possible to obtain robust estimates to inform management decisions in natural protected areas

The striped mullet (Mugil cephalus) and white mullet (Mugil curema) support artisanal fishing at the mouth of the Soto La Marina River, Gulf of Mexico, an area of great ecological value within the Laguna Madre and Rio Bravo Delta Protected Natural Area, the Terrestrial Priority Region RTP-83, and the Marine Priority Region RMP-44. Given the absence of historical catch and effort time series—a typical constraint of data-limited fisheries—a length-based frequency approach was used to estimate growth parameters, mortality rates, and the exploitation rate (E = F/Z). During 2018–2019, 1134 specimens of M. cephalus and 339 of M. curema were sampled. Due to sexual dimorphism in M. cephalus, analyses were performed separately for females, males, and combined sexes, while M. curema was analyzed with sexes combined. Growth (L∞, k) and mortality (Z, M, F) parameters for combined sexes were: M. cephalus (562 mm, 0.14 year⁻¹; 3.72, 0.21, 3.51 year⁻¹) and M. curema (329 mm, 0.15 year⁻¹; 1.46, 0.25, 1.21 year⁻¹). Exploitation rates (E) substantially exceeded Gulland (E = 0.5) and Patterson (E = 0.4) reference points: M. cephalus females (0.891), males (0.915), combined sexes (0.944), and M. curema (0.828). It is concluded that both stocks show strong evidence of growth overfishing, with exploitation rates well above established reference points, revealing a disconnect between the area’s conservation designations and the actual condition of the resource.