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Terrestrial input to marine and freshwater ecosystems colors the water yellow-brown, causing a phenomenon called “brownification”. The effect of brownification on the marine pelagic microbial food web was studied in the oligotrophic eastern Mediterranean in June 2021 by adding HuminFeed in a 15-day mesocosm experiment with 2 treatments: Control (C, no addition) and HuminFeed (HF, single dose of HuminFeed, 2 mg L-1); and 3 replicates per treatment. HuminFeed caused shading, leading to a decrease in the abundance of photo-autotrophic organisms (cyanobacteria Synechococcus and diatoms). Bacteria were positively affected by the HF addition (mainly in terms of production rather than abundance), benefiting either directly from the dissolved organic carbon (DOC) contained in HuminFeed or indirectly from the trophic cascade through the food web. Despite the decrease in HF bacterial abundance during the experiment, an increase in both the high nucleic acid containing bacteria% and heterotrophic bacterial production were observed, suggesting higher activity at the single cell level. In the HF treatment, the increased abundance of dinoflagellates observed could be due to either a dominance of mixotrophic species or a release from predation by copepods. Both ciliates and copepods were severely impacted by HuminFeed, showing lower abundance and distorted forms (ciliates) and reduced reproductive potential (copepods). In conclusion, in the ultraoligotrophic eastern Mediterranean, the simulated brownification negatively affected autotrophs and top predators while benefiting bacteria, thus indicating a shift in the structure of the plankton food web.

Informed by two theoretical models of homework effects, we extended a model of homework on mathematics achievement in a large sample of Chinese eighth graders. Our model incorporated six clusters of homework variables -- student background factors, homework characteristics, teacher variables, parent variables, student motivation, and homework behavior. Results indicated that mathematics achievement was related to at least one variable for each of the six clusters at the individual level. At the class level, mathematics achievement was associated positively with homework time, frequency, and interest, but negatively with teacher control. Finally, the combination of prior grades in mathematics and homework completion together influenced mathematics achievement. The study highlights the utility of our extended theoretical model for understanding predictive effects on achievement in a non-Western sample. The different norms and practices around homework in China are discussed, as are implications for future research.

Preventing sudden cardiac death (SCD) in athletes is a primary duty of sports cardiologists. Current recommendations for detecting high-risk cardiovascular conditions (hr-CVCs) are history and physical examination (H&P)-based. We discuss the effectiveness of H&P-based screening versus more-modern and accurate methods. In this position paper, we review current authoritative statements and suggest a novel alternative: screening MRI (s-MRI), supported by evidence from a preliminary population-based study (completed in 2018), and a prospective, controlled study in military recruits (in development). We present: 1. Literature-Based Comparisons (for diagnosing hr-CVCs): Two recent studies using traditional methods to identify hr-CVCs in >3,000 young athletes are compared with our s-MRI-based study of 5,169 adolescents. 2. Critical Review of Previous Results: The reported incidence of SCD in athletes is presently based on retrospective, observational, and incomplete studies. H&P's screening value seems minimal for structural heart disease, versus echocardiography (which improves diagnosis for high-risk cardiomyopathies) and s-MRI (which also identifies high-risk coronary artery anomalies). Electrocardiography is valuable in screening for potentially high-risk electrophysiological anomalies. 3. Proposed Project : We propose a prospective, controlled study (2 comparable large cohorts: one historical, one prospective) to compare: (1) diagnostic accuracy and resulting mortality-prevention performance of traditional screening methods versus questionnaire/electrocardiography/s-MRI, during 2-month periods of intense, structured exercise (in military recruits, in advanced state of preparation); (2) global costs and cost/efficiency between these two methods. This study should contribute significantly toward a comprehensive understanding of the incidence and causes of exercise-related mortality (including establishing a definition of hr-CVCs) while aiming to reduce mortality.

Summary:. The best breast reconstruction solution after mastectomy remains a topic of wide debate. Recently, the focus in the field of implant-based reconstruction has been on the increasing indications for prepectoral reconstruction. This offers undoubted advantages over subpectoral reconstruction, ranging from better aesthetic results and patient comfort to a less invasive procedure that spares the pectoralis major muscle, reducing pain and postoperative recovery time. The dermal sling is a reconstructive variant introduced by Bostwick in the 1990s and is commonly used to complete the subpectoral pocket in one- or two-stage reconstruction, creating a dual-plane reconstruction. This method may be indicated after mastectomy for both therapeutic and prophylactic purposes. It can also be used for unilateral and bilateral reconstructions. We propose a new meshed dermal sling technique that allows complete prepectoral reconstruction without the use of acellular dermal matrix, thus reducing the cost of reconstruction. It also allows the indication for complete prepectoral reconstruction to be extended to patients with medium breast volume and grade 1 or 2 ptosis, without the need to use acellular dermal matrix or the pectoralis major muscle to complete the breast pocket.

In the early 1980s, the crisis of punk gave rise to hardcore, which was characterised by its increased aggressiveness of performance and radical contestation of society. In America, hardcore immediately spread across much of the country, giving rise to various phenomena such as the spread of Do It Yourself with the self-production of records and tours; the proliferation of fanzines, the straight edge and skateboarding. These practices came to Italy, offering new forms of musical and political scene, which took the form of a more proactive attitude than that of the late 1970s. The article illustrates how Italian hardcore was influenced by American hardcore, which went hand in hand with British reference models in Italian punk.

The current investigation used latent profile analysis (LPA) to categorise students according to their strategies for managing mathematics homework. A sample of 918 Chinese students in grades 7-9 rated their use of seven homework management strategies; namely, arranging the environment, managing time, monitoring motivation, managing emotion, cognitively reappraising information, and handling both conventional and technological distractions. LPA identified five distinct profiles that could be labelled: "High Across All Strategies," "Moderate Across All Strategies," "Low Across All Strategies," "Low Except for Handling Distractions," and "Low Handling Distractions." Profile membership was related to homework effort, completion, and mathematics achievement. Students who profiled high across all strategies outperformed the other groups on these outcome variables. Taken together, the study's results offer insight into self-regulation of homework behaviour that can have important implications for homework research and practices.

This article discusses the role of student motivation and learning experiences in online course environments at the post- secondary level. We offer guidance for instructors to design online experiences that encourage students to learn actively, allowing them to persist at academic goals and get the most out of the material. In discussing relevant motivation theory and research, we address two questions: (1) What factors motivate post-secondary students to persist at academic goals; and (2) What online learning experiences promote student motivation and persistence? If online instruction fosters student motivation and concurrently equips them with strategies to succeed, students will be more likely to transfer learning strategies and productive work habits to future coursework and beyond. Taking teaching online can prepare students for success wherever their futures take them.