Opportunistic Scheme Research Articles

Repeatability and predictability of lying and feeding behaviours in dairy cattle

Subtle changes in behaviour, which may be useful as early indicators of disease or stress in farm animals, can be detected using precision livestock technologies. However, as animals often display differences in their baseline behaviours from one another, individual variation needs to be measured and accounted for if we want to successfully detect abnormalities. In addition to consistent individual differences in their mean behaviour, which are called behavioural types and measured by repeatability, animals may differ in the amount of day-to-day variation around their own mean. This is known as predictability and it is very rarely measured in animals as it requires data with high granularity for extended periods of time, which is hard to obtain without precision technologies. Here we aim to quantify the repeatability and predictability of lying and feeding, two behaviours which have been investigated as potential indicators of disease with inconsistent results, in dairy cows. We used data on daily lying behaviours from leg-mounted sensors for 1439 cows and data on daily feeding behaviours from neck-mounted sensors for 2584 cows belonging to multiple herds to quantify the variation between individuals, the individual differences in predictability and any correlations between individual behaviour type and predictability of the same behaviour. Using multivariate double hierarchical generalised linear models, we were able to quantify individual variation in feeding and lying behaviours of adult cows for the first time. Consistent variation between individuals was present for all measures of lying and feeding with repeatability values of 0.38 for daily feeding time and 0.34 for daily lying time. Individuals also varied in their levels of predictability with coefficients of 0.46 and 0.29 for the daily lying and feeding time respectively. Lastly, there were significant positive correlations between several behaviours and the amount of residual intra-individual variation for the same behaviour (mean lying bout length: 0.93, mean feeding bout length: 0.88), indicating that cows with the longest bouts of the two behaviours were also more variable and unpredictable, perhaps due to an opportunistic strategy. These results highlight the importance of measuring individual variation in behaviour, supporting the evidence of personality traits in cattle, as well as differences in predictability, which must be taken into account in any use of behavioural indicators for early disease diagnosis.

비동맹국가 헤징전략의 지속가능성 탐색

This article aims to examine the sustainability of non-aligned countries' hedging strategies from the perspective of efficiency. It presents the conditions for effective hedging and analyzes India's diplomatic strategy, which led the non-aligned movement during the Cold War era and now seeks to become a leader in the Global South. Effective hedging strategies involve selecting alternatives based on the consideration of potential risks and strategic costs, issuing fair and ambiguous signals to multiple great powers, and expanding multilayered and intermediate alliances and networks. India has employed a hard hedging strategy, actively enhancing security cooperation with the United States to avoid critical risks from China. Additionally, to mitigate the costs associated with hard hedging strategies, India has sent ambiguous signals to both the United States and China, while forming multilayered bilateral cooperation and intermediate and multilateral networks. Through these efforts, India has been able to reduce the feasibility of potential risks and secure leverage while maintaining strategic autonomy as a non-aligned country. The space India has secured through hedging may expand, overlapping with the space of maneuver secured by other middle powers facing pressure from great power competition. In this regard, the hedging of non-aligned countries may be sustainable not merely as opportunistic strategies driven by pragmatism under the pretext of non-alignment, but rather as efforts to pursue a multi polar order through proactive thinking and the accumulation of strategic means, influencing the international order restructuring, with countries like India possessing capabilities and positional power at its center.

Beyond borders: investigating the impact of the 2023 Israeli–Palestinian conflict on global equity markets

PurposeThe present research study aims to explore the impact of the most recent Israeli–Palestinian conflict, which unfolded in October 2023, on global equity markets, including a wide range of both emerging and developed markets (as per the Morgan Stanley Capital Investment country classification).Design/methodology/approachThe market model of event study methodology, with an estimation window of 200 days and 28-day event window (including event day, i.e. October 7, 2023), has been employed to investigate the event’s impact on the stock markets of different countries, with 24 emerging countries and 23 developed countries. The daily closing prices of the prominent indices of all 47 countries have been analyzed to examine the impact of the conflict on emerging markets, developed markets and overall global equity markets. Additionally, cross-sectional regression analysis has been performed to investigate the possible explanations for abnormal returns.FindingsThe findings of the study suggest the heterogeneous impact of the selected event on different markets. Notably, emerging markets and the overall global equity landscape exhibited substantial negative responses on the event day, as reflected in average abnormal returns of −0.47% and −0.397%, respectively. In contrast, developed markets displayed resilience, with no significant negative impact observed on the day of the event. A closer examination of individual countries revealed diverse reactions, with Poland, Egypt, Greece, Denmark and Portugal standing out for their positive or resilient market responses. Poland, in particular, demonstrated significantly positive cumulative abnormal returns (CARs) of 7.16% in the short-term and 8.59% in the long-term event windows (−7, +7 and −7, +20, respectively), emphasizing its robust performance amid the geopolitical turmoil. The study also found that, during various event windows, specific variables had a significant impact on the CARs.Practical implicationsThe study suggests diversification and monitoring of geopolitical risks are key strategies for investors to enhance portfolio resilience during the Israeli–Palestinian conflict. This study identifies countries such as Poland, Egypt, Greece, Denmark and Portugal with positive or resilient market reactions, providing practical insights for strategic investment decisions. Key takeaways include identifying resilient markets, leveraging opportunistic strategies and navigating market dynamics during geopolitical uncertainties.Originality/valueAs per the authors’ thorough investigation and review of the literature, the present study is the earliest attempt to explore the short-term and long-term impact of the 2023 Israeli–Palestinian conflict on equity markets worldwide using the event study approach and cross-sectional regression analysis.

Modelling the habitat preferences of the NE-Atlantic Sea cucumber Holothuria forskali: Demographics and abundance

Sea cucumbers' historical demand, together with the depletion of several traditional species in the market, has popularized new target species from new fishing grounds. Holothuria forskali is one of those emergent species in the trade market. However, it is a species for which there is no relevant information to allow sustainable stock management. Fundamental knowledge of the populations' structure and habitat preferences are key elements without which any measure is inconsequent. This work aims to fill that gap by modelling temporal and spatial patterns of abundance and demographic structure of this species in a NE-Atlantic area, as a function of environmental features.For a period of 15 months, nine regular sampling campaigns collected data on density, individual length, individual conditions of occurrence (e.g. sheltered, on sand, on algae cover) and environmental parameters (water column, sediment, substrate cover and type), using random transects throughout a costal rocky-reef, considering habitat heterogeneity and substrate types. To determine the species' habitat preferences Generalized Linear Models were used to model density and demographic structure of the species as a function of environmental conditions. The models revealed that the main drivers shaping the distribution of H. forskali are neither abiotic nor biotic parameters of the water column, but physical stressors, like current intensity and depth, and substrate type in a patchy distribution pattern. Estuarine conditions are generally avoided, although with a size-dependent opportunistic strategy. Larger individuals show temporal and spatial displacement patterns towards suitable reproductive conditions (pre-breeding aggregation) and favourable feeding grounds and smaller size-classes tend to aggregate in higher numbers in more stable environments.Sustainable sources for market supply, like aquaculture, are still a long way from commercial production. So, these results are fundamental to support effective conservation measures for stock management of H. forskali.

ДО ПИТАННЯ РОЗВИТКУ КРЕДИТНИХ СПІЛОК В УКРАЇНІ

The article deals with the current issues in the development of credit unions in Ukraine's financial market. It is noted that after rapid growth in the early 21st century, these financial institutions have stagnated since 2008, which negatively affects the quantitative indicators of this sector's development. The economic crisis of 2008-2009 led to the closure of many credit unions in Ukraine and destroyed trust in these financial institutions for many years. However, in terms of promoting financial inclusion, credit unions hold a special place in the modern financial market, and their potential for development in Ukraine should not be ignored. Credit unions could fill those segments of the credit market that, for various reasons, are not of interest to other financial institutions. It is noted that several factors negatively impact the functioning of credit unions in Ukraine. First, the state has failed to create an institutional environment conducive to credit unions, and significant distortions remain in the regulation of their activities. For decades, there have been discussions about establishing a deposit guarantee fund for credit union members, but this issue has yet to be resolved. Second, the strategies of domestic credit unions often do not align with global standards and principles (especially in terms of credit costs). Intense competition with banks in the deposit market has forced credit unions to unjustifiably raise interest rates on deposits, which has negatively impacted loan costs. Third, the financial literacy and culture of the population in Ukraine have also hindered the popularization of credit union services. The article justifies measures that could create «growth drivers» for credit unions in Ukraine. These measures should primarily focus on changing regulatory approaches by the state; creating an institutional environment that prevents opportunistic strategies by credit unions; and improving the population's financial literacy, particularly in their interactions with credit institutions.

Species-specific responses of marine bacteria to environmental perturbation

Environmental perturbations shape the structure and function of microbial communities. Oil spills are a major perturbation and resolving spills often requires active measures like dispersant application that can exacerbate the initial disturbance. Species-specific responses of microorganisms to oil and dispersant exposure during such perturbations remain largely unknown. We merged metatranscriptomic libraries with pangenomes to generate Core-Accessory Metatranscriptomes (CA-Metatranscriptomes) for two microbial hydrocarbon degraders that played important roles in the aftermath of the Deepwater Horizon oil spill. The Colwellia CA-Metatranscriptome illustrated pronounced dispersant-driven acceleration of core (~41%) and accessory gene (~59%) transcription, suggesting an opportunistic strategy. Marinobacter responded to oil exposure by expressing mainly accessory genes (~93%), suggesting an effective hydrocarbon-degrading lifestyle. The CA-Metatranscriptome approach offers a robust way to identify the underlying mechanisms of key microbial functions and highlights differences of specialist-vs-opportunistic responses to environmental disturbance.

Exploiting Semantic Communication for Non-Orthogonal Multiple Access

A novel semantics-empowered two-user uplink non-orthogonal multiple access (NOMA) framework is proposed for resource efficiency enhancement. More particularly, a secondary far user (F-user) employs the semantic communication (SemCom) while a primary near user (N-user) employs the conventional bit-based communication (BitCom). The fundamental performance limit, namely <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">semantic-versus-bit (SvB) rate region</i> , of the proposed semantics-empowered NOMA framework is characterized. The <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">equivalent</i> SvB rate region achieved by the conventional BitCom-based NOMA is provided as the baseline scheme. It unveils that, compared to BitCom, SemCom can significantly improve the F-user’s performance when its permitted transmit power is strictly capped, but may perform worse when its permitted transmit power is high. Guided by this result, the proposed semantics-empowered NOMA framework is investigated over fading channels. An <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">opportunistic</i> SemCom and BitCom scheme is proposed, which enables the secondary F-user to participate in NOMA via the most suitable communication method at each fading state, thus striking a good tradeoff between its own achieved performance and the interference imposed on the primary N-user. Two scenarios are considered for employing the opportunistic scheme, namely on-off resource management and continuous resource management. For each scenario, the optimal communication policy over fading channels is derived for maximizing the ergodic semantic rate achieved at the secondary F-user, subject to the minimum ergodic bit rate constraint of the primary N-user. Numerical results show that: 1) The proposed opportunistic scheme in both scenarios can achieve higher communication performance for NOMA than the baseline schemes merely employing SemCom or BitCom; 2) SemCom can better guarantee the performance of the F-user admitted in NOMA than BitCom when the communication requirement of the primary N-user is high; and 3) The continuous power control at the F-user is necessary for ensuring high performance over fading channels, while the on-off time scheduling is sufficient.

Repurposing of Chronically Used Drugs in Cancer Therapy: A Chance to Grasp

Despite the advancement in drug discovery for cancer therapy, drug repurposing remains an exceptional opportunistic strategy. This approach offers many advantages (faster, safer, and cheaper drugs) typically needed to overcome increased challenges, i.e., side effects, resistance, and costs associated with cancer therapy. However, not all drug classes suit a patient’s condition or long-time use. For that, repurposing chronically used medications is more appealing. This review highlights the importance of repurposing anti-diabetic and anti-hypertensive drugs in the global fight against human malignancies. Extensive searches of all available evidence (up to 30 March 2023) on the anti-cancer activities of anti-diabetic and anti-hypertensive agents are obtained from multiple resources (PubMed, Google Scholar, ClinicalTrials.gov, Drug Bank database, ReDo database, and the National Institutes of Health). Interestingly, more than 92 clinical trials are evaluating the anti-cancer activity of 14 anti-diabetic and anti-hypertensive drugs against more than 15 cancer types. Moreover, some of these agents have reached Phase IV evaluations, suggesting promising official release as anti-cancer medications. This comprehensive review provides current updates on different anti-diabetic and anti-hypertensive classes possessing anti-cancer activities with the available evidence about their mechanism(s) and stage of development and evaluation. Hence, it serves researchers and clinicians interested in anti-cancer drug discovery and cancer management.

Responses of two Acacia species to drought suggest different water-use strategies, reflecting their topographic distribution.

Soil water availability is a key factor in the growth of trees. In arid deserts, tree growth is limited by very dry soil and atmosphere conditions. Acacia tree species are distributed in the most arid deserts of the globe, therefore they are well adapted to heat and long droughts. Understanding why some plants do better than others in some environments is a key question in plant science. Here we conducted a greenhouse experiment to continuously and simultaneously track the whole-plant water-balance of two desert Acacia species, in order to unravel their physiological responses to low water availability. We found that even under volumetric water content (VWC) of 5-9% in the soil, both species maintained 25% of the control plants, with a peak of canopy activity at noon. Moreover, plants exposed to the low water availability treatment continued growing in this period. A. tortilis applied a more opportunistic strategy than A. raddiana, and showed stomatal responses at a lower VWC (9.8% vs. 13.1%, t4= -4.23, p = 0.006), 2.2-fold higher growth, and faster recovery from drought stress. Although the experiment was done in milder VPD (~3 kPa) compared to the natural conditions in the field (~5 kPa), the different physiological responses to drought between the two species might explain their different topographic distributions. A. tortilis is more abundant in elevated locations with larger fluctuations in water availability while A. raddiana is more abundant in the main channels with higher and less fluctuating water availability. This work shows a unique and non-trivial water-spending strategy in two Acacia species adapted to hyper-arid conditions.

The Transformation of Secularism and the BJP’s Hindu Nationalism

Since Modi came into power in 2014, secularism has significantly retreated in India’s State machinery, institutions and political discourse. Exploring the history of secularism after India’s independence, it can be concluded that India has never achieved a complete separation between the State and the religion. On the contrary, the State has rebuilt its relationship with religion by social reforms. Secularism advocated by the Indian National Congress was a mixture of both Nehru’s ideal of separation between the State and the religion and Gandhi’s ideal of religious tolerance. On many issues the latter’s stand is similar to what the Hindu nationalists argue for. The opportunistic strategy of the Congress on religion-related issues since the late 1970s further opened the door for Hindu communalism. By stigmatizing and redefining the secularism framed by the Congress, the Bharatiya Janata Party (BJP) reconstructed a political discourse about India being a secular State based on Hindu nationalism. At present, the Congress has no intention of reviving the Nehru-style tradition of secularism and other regional parties once advocating secularism have abandoned the ideal. A rightward shift in Indian party politics is inevitable. Under the BJP’s rule, a secular Indian State based on communal (religious) politics is taking shape.

Innovative Almond-Growing Strategy in Ukraine: Enterprise Level

Almond production in Ukraine is undergoing the process of formation. There is an urgent need to study the almond market in Ukraine, including the formation of production strategies. A content analysis of the scientific literature was used to single out the general approach for enterprise strategy development. With a view toward determining the regions in Ukraine with the most concentrated production of almonds, a cluster analysis was carried out. To maintain the SWOT analysis for the producers of almonds in Ukraine, a factor analysis was conducted. The incoming data for the factor analysis was obtained by surveying 98 domestic almond companies. For the development of product-based conceptual models, frequency analysis and multiple-choice analysis were applied. The main results included a conceptual model of the product portfolio, a generalized product portfolio for nut-producing enterprises in Ukraine, and a strategic approach for an almond-growing enterprise in Ukraine. Given the most promising regions for almond growing in Ukraine, the main SWOT analysis results outlined the broad prospects: lack of competition, high demand, and government support along with weak sector organization and opportunistic strategy. In addition, almond production fell under the investment production category, which was considered to require new employees.

A Qualitative Study to Explore the Role of Health Workers in Reducing Smokeless Tobacco Consumption in India

India is one of the largest smokeless tobacco consumers globally, leading to devastating health consequences. However, smokeless tobacco still remains poorly understood. Health workers have an essential role in curbing this rise in consumption by offering smokeless tobacco prevention advice. A better understanding of health workers knowledge and practice at offering preventative advice will help strengthen tobacco policies. This study aims to explorethe role of HWs offering SLT prevention advice by identifying facilitators for and barriers against implementation of this opportunistic strategy. Health workers were recruited through purposive sampling and sixteen participants took part in semi-structured online interviews. Data was transcribed verbatim and analysed through thematic analysis. Health workers stated that training was the greatest facilitator but also greatest barrier to providing smokeless tobacco prevention advice. They also thought that training during university was inadequate and external training sources were more beneficial to providing prevention advice. Smokeless tobacco training of a high standard is a major facilitator and needs providing during university and post-gradation. Smokeless tobacco needs prioritisation over smoking tobacco policies in India and stakeholders need to come together to tackle this multi-factorial problem.

Association between Earnings Announcement Behaviors and ESG Performances

Despite the rapidly growing interest in ESG business management, it is not easily attainable for stakeholders to accurately assess the quality of the ESG activities of a firm due to several problems, including the exaggeration or greenwashing of the real ESG performance. This study investigates whether managerial opportunism, as revealed by earnings announcement behaviors, can be utilized as a hallmark to forecast the quality of ESG performance. Based on the tests using Korean firms, the empirical results show that opportunistic behaviors for earnings announcement announcements, such as the announcement on Friday, after market closing, and omitting preliminary earnings disclosure, are all negatively associated with the ESG performance score on an individual and also collective basis. Further analysis shows that firms with opportunistic strategies for earnings announcement tend to miss the disclosure on ESG activities as well. In sum, this study contributes to future research and policy-making by suggesting a new practical approach to analyzing the earnings announcement behaviors as a quick test to verify the corporate ESG performance.

Risk-constrained energy management of an isolated multi-energy microgrid enhanced with hydrogen storage

Hydrogen energy has proven to be a key player in transitioning towards a carbon-neutral society. However, integrating it into existing multi-energy microgrids (MEMGs) is challenging due to uncertainties in hydrogen vehicle (HV) demand, gas and electricity demand, renewable energy output, and prices. To address this, a computationally feasible risk-constrained energy management model is developed using the information gap decision theory (IGDT) method. This model provides both robust and opportunistic strategies. The MEMG system includes electricity, hydrogen, and gas subsystems, and allows for conversions between power to hydrogen (P2H), hydrogen to power (H2P), hydrogen to gas (H2G), and gas to power (G2P). Liquified natural gas (LNG) is used as an external energy source to improve system security. The study also explores the use of hydrogen storage systems (HSS) and renewable energy for sustainability. While the problem is a mixed integer nonlinear programing model, it is converted into a mixed integer linear programing model to ensure global optimality. The proposed risk-based energy management model was tested on a case study and results showed a 2 % decrease in profit for the robust strategy and a 4 % increase in profit for the opportunistic strategy, with final profits of $4876.102 (robust) and $5171.624 (opportunistic).

Extended Framework for Preventive Maintenance Planning: Risk and Behaviour Analysis of a Proposed Optimization Model

The considerable increase in the complexity associated with the formulation of maintenance plans has enabled the development of new techniques to bring maintenance scheduling optimization models to more realistic environments. In this sense, a previous optimization model was proposed considering the use of time windows for the formation of grouping schemes under an opportunistic strategy for maintenance activities considering non-negligible execution times, thus offering the possibility of analysing scenarios with limited resources. This article proposes a risk analysis based on the failure probability of each component involved in the maintenance scheduling optimization model, which has the particularity of enabling a greater number of combinations of grouped PM activities. Moreover, it seeks to identify the general behaviour of the optimization model against different scenarios of periodicities and execution times of each maintenance activity. The proposed optimization model is formulated under a mixed integer linear programming (MILP) paradigm and its objective function seeks to minimize the unavailability of the system associated with the execution times of the activities developed, generating different experimental cases, and varying the start time scheduling under a tolerance factor from 0% up to a maximum of 25% for advance or delay. Results show in contrast with the base optimization model, an 8% less unavailability when the tolerance factor is 10%. Finally, it was possible to quantify the risk present in each maintenance schedule, at the same time a behaviour towards advancing PM activities is evidenced by the optimization model proposed over the delay.

AI-based opportunistic CT screening of incidental cardiovascular disease, osteoporosis, and sarcopenia: cost-effectiveness analysis.

To assess the cost-effectiveness and clinical efficacy of AI-assisted abdominal CT-based opportunistic screening for atherosclerotic cardiovascular (CV) disease, osteoporosis, and sarcopenia using artificial intelligence (AI) body composition algorithms. Markov models were constructed and 10-year simulations were performed on hypothetical age- and sex-specific cohorts of 10,000 U.S. adults (base case: 55 year olds) undergoing abdominal CT. Using expected disease prevalence, transition probabilities between health states, associated healthcare costs, and treatment effectiveness related to relevant conditions (CV disease/osteoporosis/sarcopenia) were modified by three mutually exclusive screening models: (1) usual care ("treat none"; no intervention regardless of opportunistic CT findings), (2) universal statin therapy ("treat all" for CV prevention; again, no consideration of CT findings), and (3) AI-assisted abdominal CT-based opportunistic screening for CV disease, osteoporosis, and sarcopenia using automated quantitative algorithms for abdominal aortic calcification, bone mineral density, and skeletal muscle, respectively. Model validity was assessed against published clinical cohorts. For the base-case scenarios of 55-year-old men and women modeled over 10years, AI-assisted CT-based opportunistic screening was a cost-saving and more effective clinical strategy, unlike the "treat none" and "treat all" strategies that ignored incidental CT body composition data. Over a wide range of input assumptions beyond the base case, the CT-based opportunistic strategy was dominant over the other two scenarios, as it was both more clinically efficacious and more cost-effective. Cost savings and clinical improvement for opportunistic CT remained for AI tool costs up to $227/patient in men ($65 in women) from the $10/patient base-case scenario. AI-assisted CT-based opportunistic screening appears to be a highly cost-effective and clinically efficacious strategy across a broad array of input assumptions, and was cost saving in most scenarios.

Different nitrogen acquirement and utilization strategies might determine the ecological competition between ferns and angiosperms.

The abundance or decline of fern populations in response to environmental change has been found to be largely dependent on specific physiological properties that distinguish ferns from angiosperms. Many studies have focused on water use efficiency and stomatal behaviours, but the effects of nutrition acquirement and utilization strategies on niche competition between ferns and flowering plants are rarely reported. We collected 34 ferns and 42 angiosperms from the Botanic Garden of Hokkaido University for nitrogen (N), sulphur (S), NO3- and SO42- analysis. We then used a hydroponic system to compare the different N and S utilization strategies between ferns and angiosperms under N deficiency conditions. Ferns had a significantly higher NO3--N concentration and NO3--N/N ratio than angiosperms, although the total N concentration in ferns was remarkably lower than that in the angiosperms. Meanwhile, a positive correlation between N and S was found, indicating that nutrient concentration is involved in assimilation. Pteris cretica, a fern species subjected to further study, maintained a slow growth rate and lower N requirement in response to low N stress, while both the biomass and N concentration in wheat (Triticum aestivum) responded quickly to N deficiency conditions. The different nutritional strategies employed by ferns and angiosperms depended mainly on the effects of phylogenetic and evolutionary diversity. Ferns tend to adopt an opportunistic strategy of limiting growth rate to reduce N demand and store more pooled nitrate, whereas angiosperms probably utilize N nutrition to ensure as much development as possible under low N stress. Identifying the effects of mineral nutrition on the evolutionary results of ecological competition between plant species remains a challenge.

Breast Cancer Screening in Latin America: The Challenge to Move from Opportunistic to Organized-Systematic Screening

Background: Breast cancer is the leading cause of death from cancer among women in Latin America. Most Latin American countries started national mammogram screening programs a decade ago. The implementation level and effects of screening programs in Latin America have not been evaluated. Aim: To evaluate the association between screening programs implementation and breast cancer mortality in selected North American and European countries compared to a group of Latin American countries with national screening programs. Methods: The study applied an ecological design with secondary data from official national and international sources. Join point regression analysis was conducted to describe the trends in mortality rates in a group of five Latin American countries (Brazil, Chile, Colombia, Costa Rica and Mexico) with five Non-Latin American countries (Canada, Spain, Sweden, United Kingdom and the United States of America). The association between screening and mortality rates was explored using correlation and linear regression. National cancer plans were assessed to describe screening strategies among selected countries. Results: A significant reduction in standardized breast cancer mortality rates was observed in all Non-Latin American countries with an Average Annual Percent Change (AAPC) of -2.00 (p&lt;.05, 95%CI [-3.33, -0.70]) for the period 2010-2020. In contrast, Latin American countries reported a significant increase in the AAPC of +1.38 (p&lt;.05, 95%CI [0.86,1.76]) in breast cancer mortality rates for the period 2010-2020. For Latin American countries, with screening rates below 50%, there was no correlation between screening and mortality rates for the period 1985-2020 (r = -0.17, p = .78). For non-Latin American countries, with screening rates over 70%, the linear regression model explained significantly 55% of the variance in mortality rates (R2aj =.55, F (5,14) = 5.69, p = .005), with a negative and significant effect of mammogram screening on mortality rates (β = -0.14, p = .01). The National Plans analysis revealed an opportunistic screening model for Latin American countries and an organized-systematic model in Non-Latin American countries. Conclusion: There is an association between the level of implementation of screening programs and mortality rates from breast cancer. Latin American countries should transform their opportunistic strategy into an organized-systematic model.

Environmental predictors of the life history of the flag tetra Hyphessobrycon heterorhabdus (Characiformes: Characidae) in streams of the Eastern Amazon

Abstract This study aimed to characterize the reproductive biology of Hyphessobrycon heterorhabdus, and its response to environmental variations in the Eastern Amazon streams. We sampled specimens every two months, between March 2019 and January 2020. The population was evaluated for sex ratio, reproductive activity, growth pattern, condition factor, size at the first sexual maturation, spawning type, and fecundity. We analyzed 180 specimens, which showed a sex ratio of 1.6 males for each female across the whole period, with 2.3 males for each female during the period of greatest reproductive activity. The peak of reproductive activity coincided with higher precipitation periods and was partially predicted by factors such as water temperature, stream discharge, dissolved oxygen, substrate complexity, and electrical conductivity. The length where 50% and 100% of population to reach sexual maturity was 18.0 and 22.0 mm for males and 19.7 and 27.0 mm for females. The oocyte diameters showed a bimodal frequency, with at least two batches of oocytes. The average fecundity of 197 oocytes. The results indicate that this species presents an opportunistic strategy, and the tactics that make up this strategy depend on variations in both the physical structure of the habitat and physicochemical aspects of the water.

Biología reproductiva de Hatcheria macraei (bagre de torrente) en el Área Natural Protegida la Ciénaga, en el centro oeste de Argentina

ABSTRACT The northwestern region of Argentina has several gaps in ichthyogeographic knowledge and there are still bodies of water without records of the species that inhabit them. When planning mitigation projects or conservation or management actions, little knowledge of the biology of a species presents itself as a restriction. Therefore, the objective is to know the reproductive biology of the torrent catfish (H. macraei) in the Natural Protected Area La Ciénaga, San Juan, with the purpose of generating basic information as a tool for the future management of these populations. The torrent catfish, Hatcheria macraei (Girard, 1855) is a Siluriformes that belongs to the Trichomycteridae family, it is a rheophilic and phototactic negative species, which is characterized by living in cold and well-oxygenated waters with sandy and rocky substrates. In a period of one year, fecundity, reproductive potential, minimum reproductive size were determined, sexual dimorphism was evaluated, and the state of gonadal development was described. It was determined that the species presents an opportunistic strategy, presenting a prolonged reproduction period from October to November.