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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="data-paper" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Russian Journal of Forensic Medicine</journal-id><journal-title-group><journal-title xml:lang="en">Russian Journal of Forensic Medicine</journal-title><trans-title-group xml:lang="ru"><trans-title>Судебная медицина</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2411-8729</issn><issn publication-format="electronic">2409-4161</issn><publisher><publisher-name xml:lang="en">Eco-Vector</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">16333</article-id><article-id pub-id-type="doi">10.17816/fm16333</article-id><article-id pub-id-type="edn">DYJUPY</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Technical reports</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Технические отчеты</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="zh"><subject>技术报告</subject></subj-group><subj-group subj-group-type="article-type"><subject>Scientific Report</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Digital comparative taxonomic analysis of diatom communities for determining the site of drowning: a technical report</article-title><trans-title-group xml:lang="ru"><trans-title>Цифровой сравнительный таксономический анализ диатомовых сообществ при установлении места утопления: технический отчёт</trans-title></trans-title-group><trans-title-group xml:lang="zh"><trans-title>用于确定溺水地点的硅藻群落数字比较分类学分析：技术报告</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0007-7542-7235</contrib-id><contrib-id contrib-id-type="spin">2407-7937</contrib-id><name-alternatives><name xml:lang="en"><surname>Nedugov</surname><given-names>Vladimir G.</given-names></name><name xml:lang="ru"><surname>Недугов</surname><given-names>Владимир Германович</given-names></name><name xml:lang="zh"><surname>Nedugov</surname><given-names>Vladimir G.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><email>nedugovvg@gmail.com</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7380-3766</contrib-id><contrib-id contrib-id-type="spin">3828-8091</contrib-id><name-alternatives><name xml:lang="en"><surname>Nedugov</surname><given-names>German V.</given-names></name><name xml:lang="ru"><surname>Недугов</surname><given-names>Герман Владимирович</given-names></name><name xml:lang="zh"><surname>Nedugov</surname><given-names>German V.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>MD, Dr. Sci. (Medicine), Assistant Professor</p></bio><bio xml:lang="ru"><p>д-р мед. наук, доцент</p></bio><bio xml:lang="zh"><p>MD, Dr. Sci. (Medicine), Assistant Professor</p></bio><email>nedugovh@mail.ru</email><xref ref-type="aff" rid="aff2"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Samara National Research University named after academician S.P. Korolev</institution></aff><aff><institution xml:lang="ru">Самарский национальный исследовательский университет имени академика С.П. Королёва</institution></aff><aff><institution xml:lang="zh">Samara National Research University named after academician S.P. Korolev</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Samara State Medical University</institution></aff><aff><institution xml:lang="ru">Самарский государственный медицинский университет</institution></aff><aff><institution xml:lang="zh">Samara State Medical University</institution></aff></aff-alternatives><pub-date date-type="preprint" iso-8601-date="2026-03-24" publication-format="electronic"><day>24</day><month>03</month><year>2026</year></pub-date><pub-date date-type="pub" iso-8601-date="2026-04-13" publication-format="electronic"><day>13</day><month>04</month><year>2026</year></pub-date><volume>12</volume><issue>1</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><issue-title xml:lang="zh"/><fpage>48</fpage><lpage>62</lpage><history><date date-type="received" iso-8601-date="2026-01-01"><day>01</day><month>01</month><year>2026</year></date><date date-type="accepted" iso-8601-date="2026-03-12"><day>12</day><month>03</month><year>2026</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2026, Eco-Vector</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2026, Эко-Вектор</copyright-statement><copyright-statement xml:lang="zh">Copyright ©; 2026,</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="en">Eco-Vector</copyright-holder><copyright-holder xml:lang="ru">Эко-Вектор</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/" start_date="2028-04-13"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-nc-nd/4.0/</ali:license_ref></license></permissions><self-uri xlink:href="https://for-medex.ru/jour/article/view/16333">https://for-medex.ru/jour/article/view/16333</self-uri><abstract xml:lang="en"><p><bold>BACKGROUND: </bold>Determination of the drowning site in forensic practice is based on comparative analysis of diatom communities. However, current methodology remains insufficiently formalized: standard ecological approaches are not applicable to paired sample comparisons (water body vs cadaver), and conclusions largely rely on subjective visual assessment. This limits objective and evidence-based interpretation and reduces the evidentiary value of forensic conclusions.</p> <p><bold>AIM: </bold>To develop a formalized method for digital paired comparative taxonomic analysis of diatom plankton and implement it as a cross-platform web application for forensic practice.</p> <p><bold>METHODS: </bold>This work describes the development of a protocol for comparative taxonomic analysis and its implementation as a web application compatible with Windows, Linux, Android, and iOS. The protocol includes three complementary metric blocks for paired comparison: overall similarity (Bray–Curtis and Hellinger distances with bootstrap testing); dominance structure (Jaccard, Sørensen–Dice, and Simpson indices, as well as rank correlations); and stability and indicator value (adapted Dufrêne–Legendre metrics). To justify threshold values and evaluate diagnostic performance, Monte Carlo simulation was performed. The application was developed using JavaScript and Python.</p> <p><bold>RESULTS: </bold>A formalized method for paired comparative taxonomic analysis was developed, replacing subjective assessment with calculation of objective metrics. A free online application, Qualitative Dual Sample Taxa Analyzer, was created. Based on Monte Carlo simulation, statistically justified threshold values were established for each metric, ensuring sensitivity and specificity of at least 95%. A key feature of the application is a bootstrap procedure that enables statistical testing of the hypothesis that the samples originate from the same water body. The combination of metrics allows multilevel analysis of the taxonomic composition of plankton extracts, whereas the web interface facilitates accessibility for forensic experts by automating calculations, standardizing procedures, and generating detailed reports.</p> <p><bold>CONCLUSION: </bold>The proposed method and software tool provide a comprehensive solution for objective and statistically validated assessment of similarity between diatom communities. Their implementation may improve the evidentiary strength, reproducibility, and standardization of forensic conclusions regarding the determination of the site of drowning.</p></abstract><trans-abstract xml:lang="ru"><p><bold>Обоснование. </bold>Установление места утопления в судебной медицине основано на сравнительном анализе сообществ диатомовых водорослей. Однако существующая методология недостаточно формализована: стандартные экологические подходы неприменимы к парному сравнению образцов (из водоёма и трупа), а выводы в значительной степени основываются на субъективной визуальной оценке. Это накладывает ограничения на объективную и обоснованную интерпретацию результатов, снижая доказательную силу экспертизы.</p> <p><bold>Цель работы. </bold>Разработка формализованного метода цифрового парного сравнительного таксономического анализа диатомового планктона и его реализация в виде кроссплатформенного веб-приложения для судебно-медицинской практики.</p> <p><bold>Методы. </bold>Работа представляет разработку протокола сравнительного таксономического анализа и его реализацию в виде веб-приложения, совместимого с операционными системами Windows, Linux, Android и iOS. Протокол включает три блока взаимодополняющих метрик для парного сравнения: общее сходство (дистанции Брея–Кёртиса и Хелленджера с бутстрэп-тестом); структура доминирования (индексы Жаккара, Сёренсена–Дайса, Симпсона, ранговые корреляции); стабильность и индикаторность (адаптированные метрики Дюфрена–Лежандра). Для обоснования пороговых значений метрик и оценки их диагностической эффективности проведено имитационное моделирование методом Монте-Карло. Код приложения составляли на языках программирования JavaScript и Python.</p> <p><bold>Результаты. </bold>Разработан формализованный метод парного сравнительного таксономического анализа, заменяющий субъективную оценку расчётом объективных метрик. Создано бесплатное онлайн-приложение Qualitative Dual Sample Taxa Analyzer. На основе моделирования методом Монте-Карло для каждой метрики установлены статистически обоснованные пороговые значения, обеспечивающие чувствительность и специфичность не менее 95%. Ключевым элементом приложения является бутстрэп-процедура, гарантирующая статистическую проверку гипотезы о происхождении проб из одного водоёма. Комбинация метрик позволяет проводить многоуровневый анализ таксономического состава экстрактов планктона, а веб-интерфейс делает метод доступным для экспертов, автоматизируя расчёты, стандартизируя процедуру и формируя детализированный отчёт.</p> <p><bold>Заключение. </bold>Предложенные метод сравнительного таксономического анализа и программный инструмент представляют комплексное решение задачи объективной и статистически валидируемой оценки сходства диатомовых сообществ. Их внедрение в практику способно повысить доказательную силу, воспроизводимость и стандартизацию судебно-медицинских заключений по установлению места утопления.</p></trans-abstract><trans-abstract xml:lang="zh"><p>论证：法医学中溺水地点的判定基于硅藻群落的比较分析。然而现有方法论缺乏充分的形式化标准：传统生态学方法不适用于样本（水体和尸体）的配对比较，且结论很大程度上依赖主观视觉评估。这限制了结果的客观合理阐释，降低了鉴定的证据效力。</p> <p>目的：开发形式化的数字配对比较分类学分析方法用于硅藻浮游生物分析，并实现为跨平台网络应用程序以供法医学实践应用。</p> <p>方法：本研究设计了一套比较分类学分析方案，并开发了兼容Windows、Linux、Android和iOS操作系统的网页应用程序。该方案包含三个互补的指标模块用于成对比较：总体相似度（采用Bray-Curtis距离和Hellinger距离配合自举检验）；优势结构（Jaccard指数、Sørensen-Dice指数、Simpson指数及等级相关分析）；稳定性与指示性（改进的Dufrêne-Legendre指标）。通过蒙特卡洛模拟法确定各指标的阈值并评估其诊断效能。应用程序采用JavaScript和Python编程语言编写代码。</p> <p>结果：开发了一种形式化的成对比较分类学分析方法，该方法通过客观度量计算取代了主观评估。创建了免费的在线应用程序Qualitative Dual Sample Taxa Analyzer。通过蒙特卡洛模拟为每个度量指标确立了统计上合理的阈值，确保敏感性和特异性不低于95%。该应用的核心是自助法（bootstrap）程序，可统计验证样本是否来自同一水体的假设。度量指标的组合支持对浮游生物提取物进行多层级分类学组成分析，而网络界面通过自动化计算、标准化流程和生成详细报告，使该方法可供专家便捷使用。</p> <p>结论：所提出的比较分类学分析方法和软件工具为硅藻群落相似性的客观且统计可验证的评估提供了完整解决方案。将其应用于实践可增强溺水地点鉴定中法医结论的证据效力、可重复性和标准化程度。</p></trans-abstract><kwd-group xml:lang="en"><kwd>comparative analysis</kwd><kwd>taxonomic composition</kwd><kwd>diatom plankton</kwd><kwd>drowning site</kwd><kwd>bootstrap test</kwd><kwd>web application</kwd><kwd>Monte Carlo simulation</kwd><kwd>technical report</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>сравнительный анализ</kwd><kwd>таксономический состав</kwd><kwd>диатомовый планктон</kwd><kwd>место утопления</kwd><kwd>бутстрэп-тест</kwd><kwd>веб-приложение</kwd><kwd>моделирование методом Монте-Карло</kwd><kwd>технический отчёт</kwd></kwd-group><kwd-group xml:lang="zh"><kwd>比较分析</kwd><kwd>分类学组成</kwd><kwd>硅藻浮游生物</kwd><kwd>溺水地点</kwd><kwd>自助法检验</kwd><kwd>网络应用程序</kwd><kwd>蒙特卡洛模拟</kwd><kwd>技术报告</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Tournois L, Hatsch D, Ludes B, Delabarde T. 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