Current Concepts Research Articles

Mathematics in classroom chemistry. Towards STE↔M integration

This article first characterises current conceptions that separate mathematics from STE by privileging either mathematics (ste|M) or STE (STE|m), whereas education should help students to develop joint reasoning (STE↔M). A theoretical framework is proposed, breaking with the way modelling is conceived in mathematics education research and considering the intermediation role of models between an empirical referent composed of objects and phenomena as perceived by the learner, and a theoretical referent. It is inspired by research into science teaching but it differs by promoting mathematical reasoning in the learner's theoretical referent. In this framework, covariations are models that give meaning to the processes perceived in the empirical referent. Modelling also allows covariations to be treated as dependencies between mathematical variables, thereby establishing a link with the theoretical referent. Epistemological considerations highlight two important dimensions: the plurality of models, and teamwork involving different approaches. School chemistry is chosen to test this framework, as it is an area where mathematical reasoning is overlooked. Two models of the process involved in a laboratory technique are proposed, one based on a mathematical function and the other on a white-box computer simulation. Innovative tasks for grade 12 students are designed and assessed in class.

Cerebral palsy: Current concepts and a glimpse into the future.

Cerebral palsy (CP) is an encompassing term for a group of permanent neurologic disorders of movement and posture commonly seen in early childhood and caused by abnormal brain development early in life. The cause of CP is unclear in the majority of patients affected and can be multifactorial, occurring in various time frames such as prenatal, intrapartum, and postpartum. Because CP is a clinical diagnosis, clinicians must have a strong understanding of the clinical presentation to ensure early diagnosis and improved outcomes for patients. This article reviews CP and describes advances in diagnosis and management; it also provides an overview of new treatments that are under investigation.

Partial Cuff Repair in Rotator Cuff Tears: Current Concepts and Clinical Considerations

Partial Cuff Repair in Rotator Cuff Tears: Current Concepts and Clinical Considerations

Age-specific over-the-top techniques for physeal sparing anterior cruciate ligament (ACL) reconstruction in skeletally immature patients: Current concepts for prepubescents to older adolescents.

Tailored surgical strategies for anterior cruciate ligament (ACL) reconstruction in skeletally immature patients are presented, emphasizing techniques to minimize growth plate damage and ensure stability. As ACL injuries in youth increase, delaying surgery can lead to joint damage and poor recovery outcomes. Using magnetic resonance imaging-based assessments of skeletal maturity, the authors propose the 'over-the-top (OTT)' approach with lateral tenodesis, adapted for three growth stages: prepubescents, young adolescents and older adolescents. For prepubescents, the extra-physeal approach avoids growth plate drilling; for young adolescents, the supra-physeal technique places tunnels above the growth plate; and for older adolescents, the trans-physeal method mirrors adult techniques, as growth plates are closing. The minimally invasive OTT technique preserves hamstring insertion, ensures isometric graft placement, and allows for combined intra- and extra-articular procedures to improve rotational control and protect the graft. Clinical outcomes highlight high return-to-sport rates, minimal growth disturbances, and low failure rates, although older adolescents show higher graft failures due to activity levels. Various adaptations of the OTT and lateral tenodesis techniques utilizing hamstring tendons provide promising solutions for addressing ACL injuries in skeletally immature patients, ranging from prepubescence to late adolescence. Assessing skeletal age and estimating remaining bone growth are essential for selecting the most appropriate surgical method. The biomechanical principles and positive clinical results observed across different patient groups highlight these techniques as effective, safe and attractive options for managing these challenging cases. LEVEL OF EVIDENCE: Level IV.

A biokinetic approach in primary knee osteoarthritis prevention and management-exploring movement profiles and kinetic chain interactions: Current concepts.

Knee osteoarthritis (OA) is a chronic disease characterized by increasing prevalence and significant physical, psychological, and economic burdens. Despite extensive research, the definition, risk factors, and effective cost-efficient treatments for knee OA remain unclear. This article aims to revisit primary knee OA, understanding its etiology, and focusing on prevention and individualized nonoperative treatment modalities. This study reviews various aspects of knee OA, including its global prevalence, economic impact, and current treatment strategies. It explores the role of mechanical loading pathways in the disease's onset, highlighting the importance of considering not only the knee but the entire kinetic chain in diagnosis and treatment. Also, it discusses knee anatomy and biomechanics during functional activities, emphasizing the role of neuromuscular control and the influence of proximal and distal joints on knee health. Current treatments focus mainly on symptom management, with limited success in disease prevention and curative interventions. This review underlines the importance of understanding the biomechanical risk factors contributing to knee OA and the necessity of individualized interventions based on biokinetic profile analysis. Knee OA management and prevention necessitate a paradigm shift from viewing it as a localized knee disease to recognizing related mechanical overloads of the human complex motion system. Identifying individual inductive elements is paramount for effective knee OA prevention, management, and rehabilitation. Future research should endeavor to identify movement profile subgroups to establish an early-stage prognosis and the impact of interventions for each group. LEVEL OF EVIDENCE V: Expert opinion based on nonsystematic review.

Polarization-dependent metasurface for vector Zernike wavefront sensing with increased dynamic range.

Metasurfaces have unique properties that make them suitable for a variety of optical applications. Not only do metasurfaces allow a great deal of design flexibility by controlling phase, amplitude, and polarization of reflected or transmitted light, they are also manufactured using mature semiconductor microprocessing techniques. Here we demonstrate a metasurface that can increase the dynamic range of Zernike wavefront sensors (ZWSs) by introducing phase diversity between two orthogonal linear polarizations in the near-infrared. The metasurface works in transmission and consists of elliptically shaped amorphous silicon nanopillars on a fused silica substrate. Wavefront sensors play an important role in segmented-mirror telescopes and enable the precise alignment needed between the segments in order to provide high-quality observations. This work has near-term implications for ground-based telescopes and is of importance for current and future mission concept formulations for exoplanet direct detection and characterization.

BUILDING EFFECTIVE CYBERSECURITY LEADERSHIP: THE CRUCIAL ROLE OF LEADERS IN PROTECTING BUSINESSES AGAINST CYBER THREATS

Today’s rapid progression in digital transformation brings new and significant security risks for businesses. Cybersecurity attacks disrupt business activities and cause significant costs, reputation damage, and customer losses. While these attacks are progressing at alarming levels, businesses focus only on the technical aspects of cybersecurity, ignoring the human factor, which is the weakest link in cybersecurity. Managers who are not aware that the most critical cybersecurity responsibility is related to managing individuals face significant challenges in the work environment. In overcoming all these difficulties, the most crucial role falls to the leaders. In addition to operational activities related to cybersecurity, leaders need to raise awareness among employees and create an effective strategy. In this context, where cybersecurity management and leadership activities intersect, cybersecurity leadership emerges as a current concept defined as directing cybersecurity activities in the most general sense. The aim of this study is to create the conceptual framework of cybersecurity leadership, examine its features, critical roles in businesses, and the factors that affect the success of such leadership. The methodology of the study focuses on a literature review that examines cybersecurity leadership, its characteristics, and its critical roles in businesses. In the literature review, several knowledge, skills, and abilities that cybersecurity leadership should have were explained, and it was concluded that strong leadership depends on an effective communication and training strategy that will increase cybersecurity awareness of employees by focusing on the human aspects as well as the technical aspects of cybersecurity.

WHO classification of melanocytic tumours

The update of the World Health Organisation (WHO) classification of skin tumours has led to new aspects in the classification of melanocytic tumours. Presentation of the classification of melanocytic tumours in light of current clinical, histological and genetic data. Review of the classification of melanocytic neoplasms in the fifth edition of the WHO classification of skin tumours, taking into account current disease concepts. Malignant melanoma is characterised by stepwise tumour progression and is aheterogeneous disease. Benign and intermediate precursor lesions with characteristic driver mutations can be defined for the different melanoma subtypes. Melanocytomas represent agrowing group of intermediate neoplasms which, from agenetic point of view, lie between nevi and melanomas and usually have abenign course. With the update of the WHO classification, genetic parameters are becoming increasingly relevant and shape the terminology. New terms such as 'melanocytoma' require amedical understanding of current disease concepts and good physician-patient communication for appropriate reporting of findings and therapy.

Current Concepts and Approaches to Development of Transport Engineering Enterprises

The research has enriched theoretical base of developing enterprises of transport machine-building, which includes systematization of principle stages of industry development, identification of key events and their after-effects and it can demonstrate higher rates and frequency of new technology arising that transforms approaches and strategies of transport engineering progressing. The article studies classifications of today’s concepts and approaches to the development of transport machine-building by groups that differ from each other in priority trends of managing enterprises of this industry and other industries of economy. The research shows that it is possible to find differences in approaches to management of transport engineering between Russian scientists and experts and their foreign colleagues, which can be connected with cultural and political characteristics of the present development of countries, however, the global trend on wider use of innovation technologies, such as business digitalization, automation of processes, new materials, approaches to organizational structure, etc. is still retained. Leading companies and research institutes keep working at introduction of AI, the Internet of things and blockchain technologies to optimize logistic chains and management of transportation stock.

Current State-of-the-Art and Perspectives in the Design and Application of Vitrimeric Systems

To fulfill the current circular economy concept, the academic and industrial communities are devoting significant efforts to plastic materials’ end-of-life. Unlike thermoplastics, which are easy to recover and re-valorize, recycling thermosets is still difficult and challenging. Conversely, because of their network structure, thermosetting polymer systems exhibit peculiar features that make these materials preferable for several applications where high mechanical properties, chemical inertness, and thermal stability, among others, are demanded. In this view, vitrimers have quite recently attracted the attention of the scientific community, as they can form dynamic covalent adaptive networks that provide the properties typical of thermosets while keeping the possibility of being processed (and, therefore, mechanically recycled) beyond a certain temperature. This review aims to provide an overview of vitrimers, elucidating their most recent advances and applications and posing some perspectives for the forthcoming years.

Nutrition in the critically ill in resource-limited settings/low- and middle-income countries.

To share current concepts and provide an overview of the contextual issues and nutrition practices in critically ill patients in resource-limited settings (RLSs)/low- and middle-income countries (LMICs). Most of the world's population reside in these settings which also carries the greatest burden of critical illness. There is a paucity of evidence on nutrition practice in critically ill patients in RLSs and international guidelines are largely based on evidence derived from high-income countries (HICs). While some recommendations are adaptable to RLSs, many are not feasible or directly transferable. Despite the challenges that may prevail, pragmatic solutions can address many of the difficulties to enhance nutrition practice and improve patient outcomes. This review provides a contemporary synopsis of nutrition practice in critically ill patients in RLSs covering the relevance of optimal nutrition, gives insights into relevant contextual issues and challenges in RLSs, evaluates recent scientific evidence and available literature pertinent to critically ill patients in RLSs, addresses nutrition guidelines, discusses some pragmatic options and solutions, deals with relevant and important complications that may arise, and offers suggestions and future considerations to enhance nutrition practice in critically ill patients in these settings.

Regional Gene Therapy for Bone Tissue Engineering: A Current Concepts Review

The management of segmental bone defects presents a complex reconstruction challenge for orthopedic surgeons. Current treatment options are limited by efficacy across the spectrum of injury, morbidity, and cost. Regional gene therapy is a promising tissue engineering strategy for bone repair, as it allows for local implantation of nucleic acids or genetically modified cells to direct specific protein expression. In cell-based gene therapy approaches, a variety of different cell types have been described including mesenchymal stem cells (MSCs) derived from multiple sources—bone marrow, adipose, skeletal muscle, and umbilical cord tissue, among others. MSCs, in particular, have been well studied, as they serve as a source of osteoprogenitor cells in addition to providing a vehicle for transgene delivery. Furthermore, MSCs possess immunomodulatory properties, which may support the development of an allogeneic “off-the-shelf” gene therapy product. Identifying an optimal cell type is paramount to the successful clinical translation of cell-based gene therapy approaches. Here, we review current strategies for the management of segmental bone loss in orthopedic surgery, including bone grafting, bone graft substitutes, and operative techniques. We also highlight regional gene therapy as a tissue engineering strategy for bone repair, with a focus on cell types and cell sources suitable for this application.

UMA TEORIA UNIFICADA DA FÍSICA: A INTERCONEXÃO ENTRE MASSA, ENERGIA, ENTROPIA E TEMPO COMO FUNDAMENTO PARA A REFORMULAÇÃO DA GRAVIDADE, DO CAMPO ELETROMAGNÉTICO E DAS INTERAÇÕES DAS PARTÍCULAS NA MECÂNICA QUÂNTICA

This scientific article explores the unification between the relationships between particles, in Quantum Mechanics, and large bodies, in the Theory of Relativity, as a conceptual path to reformulate the concepts of gravity and time, contributing to the development of a Theory of Everything. The proposal investigated six hypotheses for the results of experiments previously carried out by scientists, physicists and scholars, but which marked the history of Physics and Chemistry and which gave rise to current concepts about gravity, the electromagnetic field and interactions between particles in Quantum Mechanics. The hypotheses focused on commutability in the relationship between mass and energy, the dynamics of Time, the relationship between Gravity and the Ultraviolet Catastrophe, the relationship between Gravity and Time, the relationship between Time and the Atomic Model of Orbitals and the relationship between Time and the Electromagnetic Field of magnets. The methodology combined a theoretical review of the experiments, considering the conditions under which the experiment was carried out and the results found, and reanalysis of the results based on the relationship between entropy and time, providing a conceptual basis for the unification between Quantum Mechanics and the Theory of Relativity, through the prism of the foundation found between Time and Entropy. The results aim not only to validate the proposed hypotheses, but also to advance the understanding of fundamental concepts in physics, offering support for the construction of a broader theoretical structure, essential for the formulation of a Theory of Everything.

Current surgical treatment concepts for traumatic fractures of the thoracic and lumbar spine with osteoporotic bone substance

Osteoporosis-related vertebral fractures are among the most frequent fracture entities in geriatric patients. They are associated with far-reaching individual and socioeconomic consequences. Adequate diagnostics and treatment are therefore essential. The osteoporotic fracture (OF) score is acentral element in determining the right treatment. Although the majority of fractures can be healed with conservative treatment, achange of treatment should be considered in good time in cases of failure. Isolated cement augmentation procedures are particularly suitable for reducing pain in primarily stable osteoporotic vertebral fractures with apreserved framework structure (OF types 1-3) and alargely intact posterior edge. Dorsal cement-augmented stabilization with cementing of the fractured vertebral body leads to good results in unstable OF types 3and 4fractures. Dorsoventral procedures with cement-augmented internal fixator from the dorsal side and vertebral body replacement from the ventral side play amore subordinate role. Purely ventral procedures should be avoided in this patient group.

Non-parametric full cross mapping (NFCM): a highly-stable measure for causal brain network and a pilot application

Objective.Measuring causal brain network from neurophysiological signals has recently attracted much attention in the field of neuroinformatics. Traditional data-driven algorithms are computationally time-consuming and unstable due to parameter settings.Approach.To resolve these limits, we proposed a novel parameter-free technique, called 'non-parametric full cross mapping (NFCM)'. The NFCM adapts current convergent cross-mapping concept, and makes two improvements: (1) an improved phase-space reconstruction with constant embedding parameters and (2) cross-mapping estimate of all embedding vectors on manifolds following simplex projection.Main results.Numerical experiments verify that our NFCM has the highest quantization stability even when perturbed by system noise, and its coefficient of variation is almost lower than that of the six baseline methods. The developed NFCM is finally used in stereoelectroencephalogram analysis of drug-resistant epilepsy in children (DREC). A total of 36 seizures, comprising 18 surgical successes and 18 failures, were included to explore the brain network dynamics. The average causal coupling in epileptogenic zones of successful surgery (0.81 ± 0.04) is significantly higher than that in non-epileptogenic zones (0.40 ± 0.03) withP<0.001via Mann-Whitney-U-test. While there is no significant difference among the 18 failed surgeries.Significance.The causal brain network measured by our NFCM is confirmed as a credible biomarker for localizing epileptogenic zones in DREC. These findings promise to advance precision medicine for DREC.

Current Concepts and Clinical Applications in Cartilage Tissue Engineering.

Cartilage injuries are extremely common in the general population, and conventional interventions have failed to produce optimal results. Tissue engineering (TE) technology has been developed to produce neocartilage for use in a variety of cartilage-related conditions. However, progress in the field of cartilage TE has historically been difficult due to the high functional demand and avascular nature of the tissue. Recent advancements in cell sourcing, biostimulation, and scaffold technology have revolutionized the field and made the clinical application of this technology a reality. Cartilage engineering technology will continue to expand its horizons to fully integrate three-dimensional printing, gene editing, and optimal cell sourcing in the future. This review focuses on the recent advancements in the field of cartilage TE and the landscape of clinical treatments for a variety of cartilage-related conditions.

Approach to the Do-Not-Resuscitate patient in the periendoscopic period – survey about the current Portuguese reality

Background and Aims: Cardiopulmonary arrest is a rare but possible complication of endoscopic procedures, particularly when performed under sedation and/or analgesia. Hospitalized patients, and probably those with a Do Not Resuscitate (DNR) order, present a higher risk of severe cardiopulmonary complications during endoscopy. The request for endoscopic examination, particularly urgent procedures, is becoming increasingly more frequent in patients with Do-Not-Resuscitate orders. This study aimed to assess current practices, concepts and guideline awareness of nationally surveyed Portuguese gastroenterologists regarding the approach to code status for DNR patients in the periendoscopic period. Methods: Online anonymous and self-administered survey was adapted to the Portuguese reality and was conducted to assess gastroenterologists and gastroenterology trainees’ basic demographics data and details about current practice, personal opinions and knowledge of existing guidelines concerning the reversal of periprocedural DNR orders. Results: One hundred and forty five gastroenterologists, including 26 trainees (17.9%), responded to the survey. In patients with a DNR order, code status is rarely discussed (&lt;25% of cases) with the patient/legal representative (66.9%, n=97) or hospitalist (58.6%, n=85) and the DNR order is also rarely reversed (reversal in all (100% of cases) or most cases (75-99% of cases) in 8.3% n=12). Most respondents were unaware of the procedures necessary for DNR prescription in Portugal (81.3%, n=118), as well as existing guidelines on DNR reversal (96.5%, n=140). Regarding personal beliefs, the majority considered that in these patients, the DNR order should be reversed to an intermediate option that includes limited resuscitation maneuvers (62.1%, n=90) and that the urgency of a procedure should not influence the decision to reverse DNR (n=89, 61.4%). There was consensus on the need for recommendations on this topic for gastroenterologists (97.9%, n=142). Conclusion: Portuguese gastroenterologists usually do not revisit the DNR order before endoscopic procedures as a matter of course and consequently do not reverse it. Furthermore, we found significant variation in practices and beliefs among Portuguese gastroenterologists in their approach to the patient w

Current Concepts in Fluid Resuscitation and Vasopressor Use in Cirrhosis.

Critically ill patients with cirrhosis and liver failure not uncommonly have hypotension due to multifactorial reasons, that include hyperdynamic state with increased cardiac index, low systemic vascular resistance due to portal hypertension, following the use of beta blocker or diuretic therapy, and severe sepsis. These changes are mediated by microvascular alterations in the liver, systemic inflammation, activation of renin angiotensin aldosterone system, and vasodilatation due to endothelial dysfunction. Hemodynamic assessment includes measuring inferior vena cava indices, cardiac output and systemic vascular resistance using point-of-care ultrasound (POCUS), in addition to arterial waveform analysis, or pulmonary artery pressures, and lactate clearance to guide fluid resuscitation. Fluid responsiveness reflects the ability of fluid bolus to increase the cardiac output and is assessed effectively by POCUS, passive leg raise manoeuvre, and dynamic tests such as pulse pressure and stroke volume variation both in spontaneously breathing and mechanically ventilated patients. Albumin has pleotropic benefits through anti-inflammatory properties besides its standard action on oncotic pressure and volume expansion in patients with cirrhosis but has potential for precipitating pulmonary edema. In conclusion, fluid therapy in critically ill patients with liver disease is a complex and dynamic process that requires individualised management protocols to optimise patient outcomes.

Wide Bandwidth High-Power Triboelectric Energy Harvesting by Scotch Tape.

A triboelectric generator was proposed using commercial tape materials, which are composed of metalized poly(ethylene terephthalate) films to serve as electrodes and Scotch tape layers for power generation. Power extraction is achieved by the interaction between polypropylene and the acrylic adhesive layer when pressing and releasing, in which the atomic size gaps are formed due to van der Waals forces at the interface. The proposed triboelectric generator was sandwiched between two plastic plates to lead to a vibration-based energy harvester design with a mass attached to the top. Shaker tests were conducted by varying the vibration frequency, tape layer, and type. A peak power of 45 mW was reached at 40 Hz when using two long-lasting tape layers. The acrylic adhesive layer of long-lasting tape is thicker than other Scotch tapes, which results in higher power generation by the narrowing of atomic gaps. Combining two long-lasting tape layers and two box-lock tape layers produced a 53 mW peak power. Powering of a laser diode was demonstrated at 120 Hz. Current triboelectric generator concept can be applied to a biosensor and acoustic sensor design, as demonstrated in the paper as well.

Cірководень: механізм токсичної дії, клінічні прояви гострого отруєння, патогістологічні ознаки та стратегія лікування

Hydrogen sulphide (H2S) is a highly toxic gas. Among this group of poisonous substances – causes of death – it is second only to carbon monoxide. The mechanism of its toxicity has not been sufficiently studied and there is currently no specific antidote therapy. This gas is a high-priority chemical threat in industry, as well as a potential terrorist weapon of mass destruction, especially in wartime. Aim. Based on literary data and own researches, to summarize the current concepts of its toxicity mechanisms, clinical manifestations, treatment strategies and pathohistological signs of acute hydrogen sulphide poisoning. Materials and Мethods. Open sources of public information and scientific literature on the research topic were analysed. An analytical review of the publications of scientific online libraries PubMed, Medline, Elsevier was carried out. A retrospective analysis of the medical documentation of two cases with acute poisoning with H2S in combination with other toxic gases was carried out. The first case of acute poisoning with H2S and other sewage gases is in a patient who died in the conditions of a medical institution in the Kyiv region, who fell ill after a 15-minute stay in a household sewage septic tank. In the victim, the data of sectional and microscopic studies of lung tissue were also studied. The second case of acute H2S poisoning in combination with other gases of putrefaction is represented by three victims hospitalized at the clinic of the Research Centre of Preventive Toxicology, Food and Chemical Safety named after L.I. Medved, Ministry of Healthcare of Ukraine after cleaning a deep tank with the remains of rotten sauerkraut. One of the victims died after 6 hours. The methods of system comparative and content analysis were applied. Results. Modern ideas about the mechanism of the toxic effect of H2S indicate that it is a rapidly metabolizing systemic toxicant that affects mitochondria, is the basis for the formation of tissue hypoxia, activation of oxidative stress, inflammatory reactions, and apoptosis. Under the acute effects of H2S, the main target organs are the nervous, bronchopulmonary and cardiovascular systems. Until now, there are no specific antidotes for the treatment of H2S poisoning, so it includes oxygen, symptomatic and supportive therapy. New therapeutic agents – potential antidotes are at the stage of preclinical research, most of which are aimed at binding H2S. There is an urgent need for the development of new therapeutic agents – absorbents (scavengers) of H2S for the prevention and treatment of poisoning, reducing morbidity and mortality. Keywords: hydrogen sulphide, toxicity, acute poisoning, treatment, pathohistological signs.