Vulnerability Assessment of Food Crop Production and Climate Change: Implication for Agricultural Productivity and Development in Nigeria

Climate change poses significant challenges to agriculture, particularly in developing nations like Nigeria, where the sector is highly dependent on vulnerable rain-fed farming systems. Extreme weather events such as prolonged droughts, erratic rainfall, flooding, and rising temperatures threaten agricultural productivity, food security, and rural livelihoods. This study examines the vulnerability of food crops to climate change, focusing on smallholder farmers’ perceptions and adaptation strategies. Using a multistage sampling technique, data were collected from 480 smallholder farmers across selected agro-ecological zones in Nigeria. The study employed descriptive statistics and a crop vulnerability scale to assess the susceptibility of key food crops—maize, cassava, sorghum, rice, millet, soybean, and yam—to climate extremes. Findings reveal that drought is the most critical climate-induced stressor affecting food crops, with maize and cassava exhibiting the highest vulnerability indices. Flooding also presents a substantial risk, particularly to maize, while temperature fluctuations have relatively less severe immediate impacts. The study highlights the importance of climate information dissemination, cooperative memberships, and extension services in enhancing farmers’ resilience. However, limited access to climate information remains a significant barrier to adaptation. Given the observed variability in crop vulnerability, it is recommended to implement targeted climate adaptation strategies such as drought-resistant crop varieties, improved drainage systems, and early warning mechanisms. This study underscores the urgent need for climate-smart agricultural policies and resilience-building measures to safeguard food production and rural livelihoods in Nigeria amid escalating climate change threats.

Nonlinear Optimal and Multi-Loop Flatness-Based Control for the 6-DOF Autonomous Bicopter

Bicopter UAVs can find use in several civilian and defence applications. In the present article a solution of the nonlinear optimal control problem of 6-DOF bicopters is first attempted using a novel nonlinear optimal control method. This method is characterized by computational simplicity, clear implementation stages and proven global stability properties. At a first stage, approximate linearization is performed on the dynamic model of the 6-DOF bicopter with the use of first-order Taylor series expansion and through the computation of the system’s Jacobian matrices. This linearization process is carried out at each sampling instance, around a temporary operating point. At a second stage, an H-infinity stabilizing controller is designed for the approximately linearized model of the 6-DOF bicopter. To find the feedback gains of the controller an algebraic Riccati equation is repetitively solved, at each time-step of the control method. Lyapunov stability analysis is used to prove the global stability properties of the control scheme. Next, the article examines a multi-loop flatness-based control method for the dynamic model of the 6-DOF bicopter. The drone’s dynamics is written in the form of two chained subsystems which are shown to be differentially flat. The state vector of the second subsystem becomes virtual control input to the first subsystem, while the control inputs of the first subsystem become setpoints for the second subsystem. Local controllers for the individual subsystems invert their dynamics. The global stability properties of the multi-loop flatness-based control scheme are also proven though Lyapunov analysis.

Evaluating Orthophoto Mosaic Accuracy Using RTK UAVs and AeroPoints 2 Ground Control Points: A User’s Perspective

With the growing use of Real Time Kinematics (RTK) Unmanned Aerial Vehicles (UAVs) and advancements in ground control points (GCPs), assessing positional accuracy of UAV derived orthophoto mosaics is crucial. This study aimed to improve UAV aerial image accuracy for more reliable orthophoto mosaics by examining the positional accuracy of orthophoto mosaics derived with (1) an RTK UAV; and (2) an RTK UAV combined with AeroPoints 2 GCPs. We tested two GPS base station methods for the RTK UAV: self-determined and manually assigned coordinates. The manually assigned coordinates resulted in significantly lower root mean square error (RMSE = 0.0729 m) compared to the self-determined method (RMSE = 1.9762 m), indicating improved accuracy. For the AeroPoints 2 GCPs, we recorded coordinates from a central GCP at a known location and four additional GCPs placed in each cardinal direction. The AeroPoints 2 system showed lower RMSE at all points compared to the RTK, with the central GCP at 0.0136 m, indicating high accuracy. These findings suggest that while RTK UAVs improve accuracy with manual base station assignment, incorporating AeroPoints 2 GCPs provides consistently higher precision across multiple locations. The study highlights the potential of AeroPoints 2 GCPs and suggests further research opportunities to enhance RTK UAV accuracy in areas lacking GPS correctional networks.

Genetic Insights into Ancient Kinship and Human History: Methods, Applications, and Implications

Recent advances in ancient DNA analysis have transformed our understanding of kinship and underlying social structures in past populations. The application of next-generation sequencing technologies has enabled researchers to reconstruct the genetic makeup of ancient individuals with unprecedented precision, providing new insights into lineage, ancestry, and social organization. Ancient DNA evidence has revealed a wide range of kinship systems, including patrilineal and matrilineal descent, consanguineous marriages, female exogamy, and family-based burial practices. These findings underscore the complexity of human social relationships and the dynamic interactions between genetic inheritance, cultural traditions, and environmental factors in ancient societies. By examining case studies across different geographic and temporal contexts, this review highlights the transformative potential of ancient DNA in deciphering past human relationships. However, it also addresses key ethical concerns, including the importance of respecting cultural sensitivities and avoiding overly deterministic interpretations of genetic data. The integration of genetic evidence with archaeological and anthropological perspectives enables a more comprehensive reconstruction of ancient social systems, moving beyond simplistic genetic determinism to appreciate the intricate interconnections between biology, culture, and identity.

High-Efficiency Wireless Charging System for UAVs Based on PT-Symmetric Principle

To address the limited endurance of unmanned aerial vehicles (UAVs) and the efficiency degradation and instability in traditional wireless charging systems, this study proposes a high-efficiency UAV wireless charging system based on the parity-time (PT) symmetric principle. A non-Hermitian coupled resonator model is established, incorporating a dynamic gain-loss balancing mechanism and real-time parameter feedback control to adaptively compensate for coupling coefficient fluctuations caused by UAV positional deviations, thereby maintaining PT-symmetric phase stability. The receiver coil adopts a planar air-core spiral structure and is integrated beneath the UAV landing gear to minimize interference with aircraft operations. Experimental results show a transmission efficiency of 90.2% at 65 W output power, with both power and efficiency remaining stable in the strong coupling region. The system demonstrates strong robustness against horizontal misalignment and eliminates the need for complex relay structures or high-precision alignment. This work not only provides a theoretical foundation for the application of PT-symmetry in wireless power transfer but also offers a novel technical pathway for enhancing UAV endurance.

Biobreeding, a Bridge between Fundamental Research and Agricultural Application

Puberty through Their Lens: Insights from Youth around the World

Puberty, as the biological process of sexual maturation during adolescence, is a human generality that occurs across cultures. Primarily based on quantitative data from Western industrialized countries, puberty has been characterized as troublesome and stressful for adolescents. It has been linked to negative personal perceptions and negative consequences for psychosocial adaptation. These effects seem to be amplified by risks within proximal social interactions, which, in turn, are embedded in the broader cultural context. Using mixed-methods approach, the current exploratory study investigated the personal perceptions of puberty among adolescents from various cultural backgrounds. Data from 16 countries from Africa, America, Asia, and Europe were analyzed (13 yr., N = 715; 50.3% female). Differences in positive vs. negative personal perceptions of puberty emerged across cultures and genders, and qualitative statements of girls and boys reveal important insights into the proximal developmental mechanisms to well-being and health during the pubertal transition around the world. These findings not only enrich basic research but also inform gender-sensitive and culturally sensitive prevention and intervention tools for adolescents.

Application of recovered Carbon Black (rCB) by Waste Tire Pyrolysis as an Alternative Filler in Elastomer Products

The increasing global accumulation of End-of-Life (EoL) tires and the growing demand for fossil industrial Carbon Black (CB) call for sustainable alternative solutions. In this context, tire pyrolysis and the resulting recycled raw material recovered Carbon Black (rCB), are considered potential alternatives. In the study, various rCBs were incorporated into new elastomer compounds using a laboratory internal mixer and their properties were investigated. The compounds were selected based on examples of applications such as bicycle inner tubes and hydraulic membranes. By comparing the in-rubber properties of rCB-based compounds with CB reference compounds, an initial assessment of the potential use of rCB for the chosen products was derived. Compared to industrial carbon black, the use of rCB leads to a reduction in performance. Although increasing the filler content partially compensated for the mineral content in rCB and led to a slight improvement, it could not fully offset the performance loss.

Production and Characterization of Recovered Carbon Black (rCB) by Waste Tire Pyrolysis as a Potential Carbon Black (CB) Substitute

Recovered Carbon Black (rCB) from scrap tire pyrolysis offers a potential alternative to fossil-based virgin Carbon Black (CB) in the context of a circular economy. This study investigated the influence of pyrolysis process parameters on rCB yield and quality at laboratory and semi-industrial scales. The resulting rCBs were characterized and found to have surface and structural properties comparable to N500 and N600 series CBs, but with higher mineral and volatile contents. The quality of rCB is influenced by the feedstock composition, particularly the ratio of organic to inorganic components as well as key process parameters such as heating rate, pyrolysis temperature and residence time. Higher heating rates accelerate degradation and shift product distribution toward increased oil yield and reduced rCB formation, while higher pyrolysis temperatures lead to lower volatile content in rCB. Additionally, reactor and process design affect heat distribution, transfer efficiency, and mixing behavior, further shaping rCB properties. However, further testing is required to evaluate the actual in-rubber properties of rCBs. Therefore, additional tests are planned, incorporating rCB into butyl and nitrile rubber-based elastomer compounds, which will be addressed in a follow-up study. In addition, data from the current experiments will support a comprehensive Life Cycle Assessment (LCA) to evaluate the environmental impacts of tire pyrolysis and rCB production compared to other recycling methods, with details to follow in a future publication.

Steel and Aluminium Moulds: Comparative Analysis of Optimal Parameters to Inject Amorphous and Semicrystalline Polymers

The thermoplastic injection moulding process is very important in the plastics industry, as it enables automated production, supports high productivity and allows the production of plastic parts with complex geometries. It is possible to split into two large groups of polymers: amorphous and semicrystalline. Cooling rate and other injection moulding parameters have a great influence on the final properties of the plastic part. Regarding the use of aluminium as cavity material in injection moulds, new variables must be included in the analysis, since its thermal properties are significantly different from those presented by steels, which are traditionally used. In this way, the purpose of this study was to evaluate the effect of aluminium and steel cavities on different types of thermoplastics belonging to the two classes of polymers by assessing the injection parameters of a high-production part (automotive cup holder). In terms of productivity factors, moulds made of aluminium using semicrystalline polymers showed more significant reductions in cycle time compared to amorphous materials. Specifically, polypropylene exhibited a cycle time reduction between 40.6% and 52.5% when compared to steel moulds, while polyamide showed an even more substantial reduction, ranging between 56% and 63.5%. As for warpage, the amorphous materials displayed the lowest values for both types of moulds, but they also exhibited greater variations in isothermal simulations compared to semicrystalline materials. In relation to the mould materials, aluminium mould exhibited the lowest warping results and smaller variations compared to the isothermal analyses for all polymers.