This entry gives an overview of the main data structures and approaches used for a two-dimensional representation of the terrain surface using a digital elevation model (DEM). A DEM represents the elevation of the earth surface from a set of points. It is used for terrain analysis, visualisation and interpretation. DEMs are most commonly defined as a grid where an elevation is assigned to each grid cell. Due to its simplicity, the square grid structure is the most common DEM structure. However, it is less adaptive and shows limitations for more complex processing and reasoning. Hence, the triangulated irregular network is a more adaptive structure and explicitly stores the relationships between the points. Other topological structures (contour graphs, contour trees) have been developed to study terrain morphology. Topological relationships are captured in another structure, the surface network (SN), composed of critical points (peaks, pits, saddles) and critical lines (thalweg, ridge lines). The SN can be computed using either a TIN or a grid. The Morse Theory provides a mathematical approach to studying the topology of surfaces, which is applied to the SN. It has been used for terrain simplification, multi-resolution modelling, terrain segmentation and landform identification. The extended surface network (ESN) extends the classical SN by integrating both the surface and the drainage networks. The ESN can itself be extended for the cognitive representation of the terrain based on saliences (typical points, lines and regions) and skeleton lines (linking critical points), while capturing the context of the appearance of landforms using topo-contexts.
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Ongoing07 Apr 2025Encyclopedia MDPI is thrilled to announce significant enhancements to its Academic Video Service, which aim to improve its quality, accessibility, and functionality. Since its launch, our video service has enabled numerous scholars to present their research in a dynamic and visually engaging format, greatly enhancing its visibility and impact. Due to the overwhelmingly positive reception this service has received, we have reached a point where the number of orders we are receiving exceeds our current capacity. In order to maintain the quality of these videos and continue optimizing the service, we have made the decision to introduce a fee. However, to ensure that this service is still a cost-effective option, we have set our prices significantly below the market average. Highlights of the Upgrades to the Service Although the service will now be fee-based, we are committed to providing even more professional and comprehensive support, including the following: One-on-one video production guidance Personalized assistance to ensure your needs are fully met. Scriptwriting and English editing Expertly crafted narratives and professional English editing to ensure your research is presented clearly, accurately, and with impact. High-quality animations Visually engaging animations are created to simplify complex research and captivate your audience. Whiteboard Animations: Clean and minimalist, using hand-drawn illustrations to explain ideas step-by-step. Motion Graphics (MG) Animations: Cartoon Style: Bright, colorful, and approachable, ideal for making technical or scientific content more accessible and engaging. Hand-Drawn Style: Unique and artistic, adding a personal touch to your research while maintaining clarity and professionalism. Customized infographics (optional) We can also create tailored infographics to visually summarize key data or findings, enhancing the clarity and appeal of your video. Native voiceover Native speakers provide voiceovers to enhance the accessibility and reach of your research. Multiple rounds of revision To ensure your video accurately represents your work. Social media promotion Expanding your research's visibility and impact. Why Choose Us? The Proven Impact of Video Abstracts Research shows that a well-crafted video abstract can significantly enhance the visibility and impact of your work. It has been shown to do the following: Increase paper views by 120% （Source: 10.1007/ s11192-019-03108-w） Boost citations by 20% （Source: Wiley Online Library） Improve journal rankings by 33% （Source: Research Square） Raise Altmetrics scores by 140% （Source: Research Square） Our Expertise in Academic Research Backed by MDPI, our experienced production team combines deep academic knowledge with creative excellence. We understand the nuances of scholarly communication and ensure that every frame accurately conveys the value of your research, meeting the highest standards of quality and precision. Collaborations with SCI Journals We have partnered with many SCI journals to create exclusive video series, enhancing the dissemination and impact of published research. For example, our collaborations with Entropy, Remote Sensing, Nanomaterials , Animals , Nutrients, Foods , Sustainability, Encyclopedia, Cancers, etc., have helped authors achieve greater visibility and recognition for their work. Global visibility The videos are linked to your paper's DOI for maximum exposure. Available Video Services and Their Pricing Video Abstract (up to 5 minutes long): Summarizes the key findings, methodology, and significance of your research paper. Regular price: CHF 600 Discounted Price: CHF 400 Short Take (up to 2 minutes long): Uses original animations to explain the specific aspects of your research. Regular price: CHF 500 Discounted Price: CHF 300 Scholar Interview: A face-to-face discussion offering deeper insights into your publication. Regular price: CHF 400 Discounted Price: CHF 200 Special Offer To express our gratitude for your support, we are pleased to offer a buy one get one free promotion. This offer is valid for two weeks, and the complimentary service provided can be utilized within one year. Video Production Service If you want to see some examples of our videos, please visit https://encyclopedia.pub/video. If you would like to apply for the video service, please click https://encyclopedia.pub/video_service. Others If you have any other questions, please contact office@encyclopedia.pub. -
Announcement18 Jul 2025Every year, thousands of people worldwide are bitten by ticks—but not all tick bites are harmless. One of the most well-known dangers is Lyme disease, a stealthy illness that can mimic other health conditions and, if left untreated, cause long-lasting complications. 1. What Is Lyme Disease? Lyme disease is a bacterial infection caused by Borrelia burgdorferi, transmitted to humans through the bite of infected black-legged ticks (also known as deer ticks). It was first recognized in Lyme, Connecticut, in the 1970s, hence the name. Though most common in the United States, Europe, and parts of Asia, Lyme disease has become an increasing public health concern due to rising tick populations linked to climate change and habitat expansion. Source: Encyclopedia Scientific Infographics (https://encyclopedia.pub/image/3685) 2. How Is It Transmitted? Ticks don’t jump or fly—they crawl onto animals or people when brushing against tall grass, leaf litter, or shrubs. An infected tick needs to attach to a person for 24–48 hours to transmit Borrelia burgdorferi into the bloodstream. Many people are unaware they've even been bitten due to the tick's small size (especially in its nymph stage). 3. Symptoms to Watch Out For Lyme disease often progresses in stages. Early detection is key, but symptoms can vary: Early Localized Stage (3–30 days after bite): Erythema migrans (EM) rash: Often in a "bull's-eye" pattern, but not always Fever, chills Fatigue Muscle and joint aches Swollen lymph nodes Early Disseminated Stage (days to weeks): Multiple EM rashes Neurological symptoms (e.g., facial palsy, meningitis-like symptoms) Shooting pains or numbness Heart palpitations or irregular heartbeat (Lyme carditis) Late Stage (months later): Arthritis, especially in the knees Cognitive issues (memory, concentration) Chronic fatigue Nerve pain 4. How Is Lyme Disease Diagnosed? Diagnosis can be challenging, especially if the characteristic rash is absent. It typically involves: Medical history & symptom review Two-tiered blood testing (ELISA followed by Western blot) In some cases, lumbar puncture or imaging may be used if neurological symptoms are present. Because Lyme antibodies can take weeks to develop, early blood tests may yield false negatives. 5. Treatment and Recovery Most Lyme disease cases can be effectively treated with a 2–4 week course of antibiotics, such as doxycycline, amoxicillin, or cefuroxime. Early treatment leads to full recovery in the majority of patients. However, some individuals experience lingering symptoms—Post-Treatment Lyme Disease Syndrome (PTLDS)—which may include fatigue, joint pain, or brain fog. The exact cause is still under investigation. For more information about topic, you can view the online infographic entitled "Lyme Disease". -
Announcement10 Jul 2025If you've ever struggled with long-term sinus issues or recurring ear infections, you're not alone. Chronic rhinosinusitis (CRS) and chronic otitis media (COM) are two of the most common conditions seen in ear, nose, and throat (ENT) clinics. Traditionally treated as separate problems, new research suggests they may actually be more closely linked than we thought. A recent systematic review has revealed an important connection between the two—one that could change how both conditions are diagnosed and managed. 1. Two Conditions, One Underlying Cause? CRS is characterized by persistent inflammation of the nasal and sinus passages, often leading to nasal congestion, facial pressure, and a reduced sense of smell. COM, on the other hand, is a chronic infection or inflammation of the middle ear, which can cause symptoms like hearing loss, ear discharge, and balance problems. At first glance, they may seem unrelated. But both conditions share several underlying mechanisms: Chronic bacterial infections Obstruction of ventilation pathways Biofilm formation (a layer of resistant bacteria) Long-term inflammation of similar epithelial tissue In fact, the middle ear and sinuses are lined with the same type of mucosal tissue and are anatomically linked via the Eustachian tube, allowing inflammation to potentially spread between them. 2. What the Research Tells Us This systematic review analyzed data from nearly 20,867 patients with CRS, revealing that about 4.75% were also diagnosed with COM. While that may seem like a small percentage, it’s clinically significant, especially considering the chronic and often debilitating nature of both conditions. The findings suggest that COM may not be an isolated ear issue, but instead an extension of a broader, system-wide inflammatory process. In other words, what starts in the nose may travel to the ears—or vice versa. 3. Why This Matters Understanding the link between CRS and COM could lead to: Earlier diagnosis of hidden or coexisting conditions More comprehensive treatment plans targeting both nose and ear Fewer complications, including hearing loss or recurrent infections Better quality of life for patients with chronic ENT issues In practical terms, ENT specialists should evaluate both the sinuses and middle ear when patients present with symptoms of either condition. A patient with sinus inflammation should receive an ear exam, while those with chronic ear infections may benefit from a full nasal and sinus workup.A Call for More Research—and Integrated Care While this review provides valuable insight, the current number of studies on this topic is limited. More well-designed, prospective studies are needed to confirm the association and explore how best to manage both conditions together. Still, the takeaway is clear: CRS and COM are often interconnected and should no longer be viewed in isolation. For more information about topic, you can view the online video entitled "Chronic Otitis Media in Patients with Chronic Rhinosinusitis". -
Ongoing30 Apr 2025We are pleased to announce that the “Encyclopedia Outstanding Contributor Award” in 2025 is now open for applications. In 2025, we will award two outstanding contributors to the Encyclopedia platform (https://encyclopedia.pub/) and the journal Encyclopedia. After a thorough evaluation, the journal award committee, led by Editor-in-Chief Prof. Dr. Raffaele Barretta, will select all eligible contributors. The winners will be announced in March 2026. The Prize – CHF 300 (Swiss francs);– An opportunity to publish one paper free of charge in the Encyclopedia journal before 31 December 2026, following peer review;– An electronic certificate. Eligibility and Requirements To be eligible, applicants must meet at least one of the following criteria:– The applicants must have published at least one qualified entry/video/image on the Encyclopedia platform in 2025;– The applicants must have published at least one paper in the Encyclopedia journal in 2025. Application Deadline 15 January 2026. Winner announcement 31 March 2026. Please send your curriculum vitae/resume to our Editorial Office before the above deadline (encyclopedia@mdpi.com). As mentioned above, the winners will be announced on the journal's website in March 2026. Kind regards, Encyclopedia Editorial Office.
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