Biomonitoring Research Articles

Altered Haematological Parameters in Gasoline Station Workers Due to Benzene Exposure

Benzene is harmful to human health and early detection of haematological alterations is important in preventing adverse health effects. This study aimed to investigate the biomarkers of benzene exposure and its effects due to haematological alterations. Gasoline station workers with potential risks according to the biomatrix concerning benzene exposure underwent blood and urine evaluation for the biological monitoring of urinary trans, trans-muconic acid (tt-MA), and haematological and biochemical parameter evaluation. The results were analysed for correlations between biological and haematological effects. The tt-MA biomarker was detected in some workers and approximately 50% of workers had a blood profile that showed abnormal parameters with respect to the haemoglobin (Hb), haematocrit (Hct) and white blood cell parameters, which were outside the normal range. A significant correlation was observed between the tt-MA biomarker’s level and the levels of the haematological and biochemical parameters, which were Hb, Hct, eosinophil, neutrophil, SGOT and blood creatinine. The level of urinary tt-MA as a marker of benzene exposure correlated with haematological and biochemical changes in the blood, suggesting that the gasoline station workers were affected by benzene exposure. Moreover, the current study suggests that early detection of haematological abnormalities may be possible by analysing biomarkers of their effects through regular health surveillance of workers.

Bridging biological and food monitoring: A colorimetric and fluorescent dual-mode sensor based on N-doped carbon dots for detection of pH and histamine

Rapid and sensitive monitoring of pH and histamine is crucial for bridging biological and food systems and identifying corresponding abnormal situations. Herein, N-doped carbon dots (CDs) are fabricated by a hydrothermal method employing dipicolinic acid and o-phenylenediamine as precursors. The CDs exhibit colorimetric and fluorescent dual-mode responses to track pH and histamine variations in living cells and food freshness, respectively. The aggregation-induced emission enhancement and intramolecular charge transfer result in a decrease in absorbance and an increase in fluorescence, which become readily apparent as the pH changes from acidic to neutral. This property enables precise differentiation between normal and cancerous cells. Furthermore, given the intrinsic basicity of histamine, pH-responsive CDs are advantageous for additional colorimetric and fluorescent monitoring of histamine in food freshness, achieving linearities of 25–1000 µM and 30–1000 µM, respectively, which are broader than those of alternative nanoprobes. Interestingly, the smartphone-integrated sensing platform can portably and visually evaluate pH and histamine changes due to sensitive color changes. Therefore, the sensor not only establishes a dynamic connection between pH and histamine for the purposes of biological and food monitoring, but also presents a novel approach for developing a multifunctional biosensor that can accomplish environmental monitoring and biosensing simultaneously.

New approach methods in chemicals safety decision-making – Are we on the brink of transformative policy-making and regulatory change?

Decision-making on the use and management of chemicals in society is on the brink of a scientific and technological revolution. At the same time world politics is focusing more on chemicals, waste and pollution prevention, alongside climate change and biodiversity loss. To enable effective decision-making, policy makers and regulators will need to draw upon the best scientific evidence available on the real-life causation and consequences of adverse effects of chemical and waste exposures affecting humans, wildlife and the environment. New Approach Method (NAM) data from modern day multidisciplinary science and technology is becoming more available using cheminformatics, computational prediction algorithms using AI, transcriptomics, genomics, proteomics, mathematical modelling, epidemiology, biological monitoring, and clinical science. Current chemical regulation has been shaped by the animal models of the 20th century. NAMs and Next Generation Risk Assessment (NGRA) have the potential to better support innovations in chemicals and materials through science-informed decision making that is more species-relevant and protective of adverse outcomes; this will require future-proofed regulatory transformation. Capacity building and skills development in computational and in vitro NAMs will be key to this transformation.

The river health of Alista River based on macroinvertebrates communities at Selorejo Village Dau Subdistrict Malang Regency

The Alista River is one of the rivers in the upstream Brantas watershed which has relatively natural conditions, but currently there are agricultural activities on the riverbank. The aim of this study was to analyze the health status in Alista River based on the macroinvertebrate communities. This study uses a survey method. Sampling was carried out at 5 stations based on different land use. Sampling of macroinvertebrates used the kicking technique with a hand net with a mesh size of 500 μm in a 10 meter long riffle area. Data analysis used the value of BMWP index (Biological Monitoring Working Party) and the ASPT (Average Score Per Taxon). The results of the identification of macroinvertebrates found were 38 families for instance Glossossomatidae, Lepidosmatidae, and Richardsonianidae. The families belong to 10 orders and 3 classes. The lowest family is 11 families at station 5 (citrus and bamboo gardens). The highest families are 29 families at station 3 (citrus gardens and forests). The results show BMWP-ASPT score ranged from 6.3–4.3 indicating excellent to moderately poor health status. Stations with excellent categories, namely stations 1,2,3,4. Station land use 1,2,3 secondary forest before tourism was discovered including Glossosomatidae. Station 4′s land use is in the form of a tourism location and Lumbriculidae has been found. Stations in the moderately poor category, namely station 5 which is located after tourism sites (citrus gardens and settlements) were found Richardsonianidae.

What do diatom indices indicate? Modeling the specific pollution sensitivity index

Diatoms are commonly used in environmental assessments to detect pollution and eutrophication. The specific pollution sensitivity index (SPI) is one of the most frequently used indices, which assigns scores to diatom taxa based on their sensitivity to pollution. The study analyzed diatom communities in the Duero River basin in Spain to examine the relationship between SPI scores and various limnological variables. A GLM model showed that phosphates, nitrites, and water temperature were the main factors explaining SPI variability. The study also reviews previous results using SPI for water quality monitoring in different world regions, highlighting the role of nutrients in general as major drivers of SPI values worldwide. Overall, the findings reinforce the reliability of SPI as a metric for biological monitoring in various watercourses.

On-line biological oxygen demand (BOD) monitoring using a microbial membrane reactor

An on-line biological oxygen demand (BOD) monitoring instrument, utilizing an in-situ microbial membrane reactor, automates membrane cultivation, calibration, and rapid BOD detection, eliminating reagent pollution is presented. The core instrument used was an STM32F103RCT6 microcontroller embedded in the FreeRTOS real-time operating system. A series of practical application tests were carried out by the instrument. The results demonstrate that the instrument provides good stability and accuracy in detecting multiple concentrations of glucose and glutamic acid (GGA) standards, with a relative error range and relative standard deviation range from −3.01 to 11.88% and 4.19 to 6.69%, respectively. The tested water samples had a relative error range from −4.93 to 13.37%. The on-line monitoring instrument for BOD has been tested for almost three months and has shown stable performance, high accuracy, and real-time, in-situ, and on-line BOD detection. In the past three months of application testing, the on-line biological oxygen demand monitoring instrument has shown stable performance, good accuracy, and real-time, in-situ, and on-line BOD measurements. This device has significant environmental benefits for continuous water quality monitoring and the timely monitoring of water pollution.

Biomonitoring for workplace exposure to copper and its compounds is currently not interpretable

This paper sets out to explore the requirements needed to recommend a useable and reliable biomonitoring system for occupational exposure to copper and its inorganic compounds. Whilst workplace environmental monitoring of copper is used to measure ambient air concentrations for comparison against occupational exposure limits, biological monitoring could provide complementary information about the internal dose of workers, taking into account intra-individual variability and exposure from all routes. For biomonitoring to be of reliable use for copper, a biomarker and the analytical ability to measure it with sufficient sensitivity must be identified and this is discussed in a range of matrices. In addition, there needs to be a clear understanding of the dose-response relationship of the biomarker with any health-effect (clinical or sub-clinical) or, between the level of external exposure (by any route) and the level of the copper biomarker in the biological matrix being sampled, together with a knowledge of the half-life in the body to determine accurate sampling times. For many biologically non-essential metals the requirements for reliable biomarkers can be met, however, for ‘essential’ metals such as copper that are under homeostatic control, the relationship between exposure (short- or long-term) and the level of any copper biomarker in the blood or urine is complex, which may limit the use and interpretation of measured levels. There are a number of types of biomarker guidance values currently in use which are discussed in this paper, but no values have yet been determined for copper (or its inorganic compounds) due to the complexity of its essential nature; the US The American Conference of Governmental Industrial Hygienists (ACGIH) has however indicated that it is considering the development of a biological exposure index for copper and its compounds. In light of this, we present a review of the reliability of current copper biomarkers and their potential use in the occupational context to evaluate whether there is value in carrying out human biomonitoring for copper exposure. Based on the available evidence we have concluded that the reliable use of biomonitoring of occupational exposure to copper and its application in risk assessment is not possible at the present time.

Bioindicator responses to extreme conditions: Insights into pH and bioavailable metals under acidic metal environments

Acid mine drainage (AMD) caused environmental risks from heavy metal pollution, requiring treatment methods such as chemical precipitation and biological treatment. Monitoring and adapting treatment processes was crucial for success, but cost-effective pollution monitoring methods were lacking. Using bioindicators measured through 16S rRNA was a promising method to assess environmental pollution. This study evaluated the effects of AMD on ecological health using the ecological risk index (RI) and the Risk Assessment Code (RAC) indices. Additionally, we also examined how acidic metal stress affected the diversity of bacteria and fungi, as well as their networks. Bioindicators were identified using linear discriminant analysis effect size (LEfSe), Partial least squares regression (PLS-R), and Spearman analyses. The study found that Cd, Cu, Pb, and As pose potential ecological risks in that order. Fungal diversity decreased by 44.88% in AMD-affected areas, more than the 33.61% decrease in bacterial diversity. Microbial diversity was positively correlated with pH (r = 0.88, p = 0.04) and negatively correlated with bioavailable metal concentrations (r = −0.59, p = 0.05). Similarly, microbial diversity was negatively correlated with bioavailable metal concentrations (bio_Cu, bio_Pb, bio_Cd) (r = 0.79, p = 0.03). Acidiferrobacter and Thermoplasmataceae were prevalent in acidic metal environments, while Puia and Chitinophagaceae were identified as biomarker species in the control area (LDA>4). Acidiferrobacter and Thermoplasmataceae were found to be pH-tolerant bioindicators with high reliability (r = 1, P < 0.05, BW > 0.1) through PLS-R and Spearman analysis. Conversely, Puia and Chitinophagaceae were pH-sensitive bioindicators, while Teratosphaeriaceae was a potential bioindicator for Cu–Zn–Cd metal pollution. This study identified bioindicator species for acid and metal pollution in AMD habitats. This study outlined the focus of biological monitoring in AMD acidic stress environments, including extreme pH, heavy metal pollutants, and indicator species. It also provided essential information for heavy metal bioremediation, such as the role of omics and the effects of organic matter on metal bioavailability.

Social Implementation and Measurement Accuracy Verification of Non-contact Biological Monitors

In this research, for the purpose of social implementation, we conducted a near-miss demonstration experiment using a car driving in the city and a drive-simulator. Next, we conducted a demonstration experiment to evaluate the reliability of biometric information measured on patients in a medical facility's recuperation ward and residents of a special nursing home. NBC-1100 emits radar waves from a distance of up to 3 meters from an object and uses the reflected waves to measure biological information such as pulse waves and breathing waves. The multi-element pyroelectric effect was used to measure body temperature by detecting infrared radiation emitted from distant objects. This device is unique in that it can measure biological information without being restrained while wearing clothes. In the demonstration test, simultaneous measurements were conducted on nine healthy men aged 45 to 65 using a pharmaceutically approved product (μBP-mp) and a prototype non-contact biological monitor (NBC-1100 manufactured by K&amp;S Co., Ltd.). The demonstration experiments at medical institutions and nursing care facilities were conducted with the consent of residents and their families and were conducted on 30 men and women between the ages of 70 and 94 who were undergoing treatment or in need of care. The tests were conducted on residents with chronic diseases such as dilated gastrostomies, symptomatic epilepsy, hypertension, Alzheimer's disease, and progressive supranuclear palsy. The evaluation method was simultaneous measurement using a master meter (μBP-mp) and a test meter (NBC-1100).

KEANEKARAGAMAN SERANGGA PADA TIGA TIPE VEGETASI DI BLOK LAMBOSIR TAMAN NASIONAL GUNUNG CIREMAI

This study aims to determine the diversity of insects and their role in 3 different land covers, namely mixed forest, shrubs and calliandra vegetation in the Lambosir Block area of Gunung Ciremai National Park. This research was carried out in the Lambosir Block in the Gunung Ciremai National Park area in February - June 2022 using 5 traps, namely Butterfly net, Sweep net, Light trap, Aerial bait trap and Yellow Trap. using the total density, frequency and the Shanon Weiner Diversity Index. The results showed that on the land cover of shrubs, calliandra and mixed forests, 42 species of insects were found from 8 orders with 246 individual species with a diversity value of 3.18 or in the high category. The 8 orders found in 3 land covers included Coleoptera 4 species, Diptera 3 species, Hemiptera 4 species, Hymenoptera 4 species, Lepidoptera 23 species, Odonata 1 species, Orthoptera 2 species and Phasmatodea 1 species. In addition to the high diversity category, insects that exist in 3 land covers have various roles such as pollinators, decomposers, assisting ecological succession, bio indicators and predators. The correlation between land cover with the number of species and the number of individual species based on the Scatter plot has a correlation value of 91%.&#x0D; Keywords; Diversity, insect, conservation, rehabilitation zone, Lambosir

Recent Progress on Microfluidics Integrated with Fiber-Optic Sensors for On-Site Detection.

This review introduces a micro-integrated device of microfluidics and fiber-optic sensors for on-site detection, which can detect certain or several specific components or their amounts in different samples within a relatively short time. Fiber-optics with micron core diameters can be easily coated and functionalized, thus allowing sensors to be integrated with microfluidics to separate, enrich, and measure samples in a micro-device. Compared to traditional laboratory equipment, this integrated device exhibits natural advantages in size, speed, cost, portability, and operability, making it more suitable for on-site detection. In this review, the various optical detection methods used in this integrated device are introduced, including Raman, ultraviolet-visible, fluorescence, and surface plasmon resonance detections. It also provides a detailed overview of the on-site detection applications of this integrated device for biological analysis, food safety, and environmental monitoring. Lastly, this review addresses the prospects for the future development of microfluidics integrated with fiber-optic sensors.

Research on Occupational Poisoning and Biological Monitoring

A new system for the regulation of chemical substances was introduced in Japan in April 2023. Unlike delineated rules, the new system does not specify any specific measures for individual substances, but is rather based on the management of health through the voluntary implementation of measures in order to reduce exposure to all dangerous/hazardous chemical substances. Regarding specific methods, exposures will be mainly elucidated through the measurement of a work environment. However, the necessity of biological monitoring should also be considered. This study aimed to identify the importance of biological monitoring by reviewing changes made over time in biological monitoring methods used for occupational poisoning. The study presents occupational poisoning by several compounds (methyl bromide, polycyclic aromatic hydrocarbons, and MOCA) and the corresponding biological monitoring methods utilized, as researched by the author. Changes in biological monitoring based on the history of the Study Group on Occupational Poisoning and Biological Monitoring of the Japan Society for Occupational Health are also introduced. The areas of occupational poisoning at different times and cases of occupational cancer caused by exposure to chemical substances were presented in lectures held by the Study Group on Occupational Poisoning and Biological Monitoring. These lectures showed that although biological monitoring was previously implemented primarily by measuring the urinary metabolites of the exposed substance, the monitoring methods used have changed as the nature of exposure has changed, leading to the development of new tools that detect trace, low concentration, and mixed exposures. The health management of workers handling chemical substances at occupational sites will be shifted to autonomous management. However, it should be noted that only biological monitoring can detect and prove true exposure. Particularly, risk assessment by biological monitoring is necessary for substances that are suspected to be absorbed through the skin, and the measurement methods used should continue to be developed and refined. The significance of biological monitoring will continue to increase.

Typology and classification of water quality in an intermittent river in a semi-arid Mediterranean climate.

The typology and classification of rivers are highly relevant concepts in the field of limnology and freshwater ecology. Water body typology systematically categorizes water bodies based on their natural attributes, while water body classification groups them based on specific criteria or purposes for management, regulatory, or administrative reasons. Both concepts play important roles in understanding and managing water resources effectively. This scientific article focuses on the ZAT River in Morocco as a model for studying low-flow and intermittent rivers. The objective is to develop an accurate model for the typology and classification of small, low-flow rivers into homogeneous classes based on natural and anthropogenic factors. The study also investigates the impact of human activities on altering the uniformity and reference nature of the water body. The typology of water bodies is carried out according to the European methodology specified in The European Commission's Water Framework Directive (WFD) in 2000. The classification of water bodies is conducted by assessing their chemical and biological quality using the weighted index (WI), the Iberian Biological Monitoring Working Group (IBMWP) index, and multivariate statistical methods such as principal component analysis (PCA) for confirming water quality assessment. The results indicate the possibility of dividing the basin into four water bodies. Water bodies show homogeneity in terms of chemical quality when human influence is minimal or during periods of high river flow. However, increased human influence and decreased river flows lead to heterogeneity in chemical quality, indicating an unstable state. This study is the first of its kind in arid and semi-arid intermittent rivers, where such an approach could be suggested to determine their typology and classification.

Determination of water quality through using bioindicators, physical-chemical and microbiological analysis of the lagoon Santo Domingo of the national park Cotopaxi, province of Pichincha, period 2018

The current research project carried out in the Santo Domingo Lagoon of the Cotopaxi National Park, a Protected Area that is located in the canton of Mejia, province of Pichincha, and retains their transcendental goal to determine the water quality from the application of bioindicators and physical-chemical and microbiological laboratory analysis. They obtained results about the quality of water using bioindicators according to the methodology used (scientific induction, inductive, deductive, measurement, quantitative), where samples were taken at five specific points of entry and exit of the lake body in April, May and June, making use of water quality identification techniques for tolerance; Biological Monitoring Working Part (BMWP/Col.), Ephemeroptera, Plecoptera, Tricoptera (EPT), Andean Biotic Index (ABI), and Biotic Index of Families (IBF). Meanwhile, the environmental quality indices were used for the physical, chemical and microbiological analysis: DINUS - Fundación Nacional de Saneamiento (NFS), defining that the water conditions are wrong or contaminated. By contrast, from the application of the BMWP/Col. and ABI indices, the water quality pertains to waters of questionable and critical condition. However, with the application of the BMWP/Col. and ABI indices, it was defined that the water quality corresponds to waters of doubtful and critical condition, which are, in conclusion, very contaminated waters. On the other hand, one of the techniques for using bioindicators from the IBF index yielded a different result in areas of apparent organic contamination, determining that the Santo Domingo Lagoon demonstrates an "excellent" indicator. Keywords: water, analysis, bioindicators, quality, indices, lagoon.

Determination of water quality through using bioindicators, physical-chemical and microbiological analysis of the lagoon Santo Domingo of the national park Cotopaxi, province of Pichincha, period 2018

The current research project carried out in the Santo Domingo Lagoon of the Cotopaxi National Park, a Protected Area that is located in the canton of Mejia, province of Pichincha, and retains their transcendental goal to determine the water quality from the application of bioindicators and physical-chemical and microbiological laboratory analysis. They obtained results about the quality of water using bioindicators according to the methodology used (scientific induction, inductive, deductive, measurement, quantitative), where samples were taken at five specific points of entry and exit of the lake body in April, May and June, making use of water quality identification techniques for tolerance; Biological Monitoring Working Part (BMWP/Col.), Ephemeroptera, Plecoptera, Tricoptera (EPT), Andean Biotic Index (ABI), and Biotic Index of Families (IBF). Meanwhile, the environmental quality indices were used for the physical, chemical and microbiological analysis: DINUS - Fundación Nacional de Saneamiento (NFS), defining that the water conditions are wrong or contaminated. By contrast, from the application of the BMWP/Col. and ABI indices, the water quality pertains to waters of questionable and critical condition. However, with the application of the BMWP/Col. and ABI indices, it was defined that the water quality corresponds to waters of doubtful and critical condition, which are, in conclusion, very contaminated waters. On the other hand, one of the techniques for using bioindicators from the IBF index yielded a different result in areas of apparent organic contamination, determining that the Santo Domingo Lagoon demonstrates an "excellent" indicator. Keywords: water, analysis, bioindicators, quality, indices, lagoon.

Determination of water quality through using bioindicators, physical-chemical and microbiological analysis of the lagoon Santo Domingo of the national park Cotopaxi, province of Pichincha, period 2018

The current research project carried out in the Santo Domingo Lagoon of the Cotopaxi National Park, a Protected Area that is located in the canton of Mejia, province of Pichincha, and retains their transcendental goal to determine the water quality from the application of bioindicators and physical-chemical and microbiological laboratory analysis. They obtained results about the quality of water using bioindicators according to the methodology used (scientific induction, inductive, deductive, measurement, quantitative), where samples were taken at five specific points of entry and exit of the lake body in April, May and June, making use of water quality identification techniques for tolerance; Biological Monitoring Working Part (BMWP/Col.), Ephemeroptera, Plecoptera, Tricoptera (EPT), Andean Biotic Index (ABI), and Biotic Index of Families (IBF). Meanwhile, the environmental quality indices were used for the physical, chemical and microbiological analysis: DINUS - Fundación Nacional de Saneamiento (NFS), defining that the water conditions are wrong or contaminated. By contrast, from the application of the BMWP/Col. and ABI indices, the water quality pertains to waters of questionable and critical condition. However, with the application of the BMWP/Col. and ABI indices, it was defined that the water quality corresponds to waters of doubtful and critical condition, which are, in conclusion, very contaminated waters. On the other hand, one of the techniques for using bioindicators from the IBF index yielded a different result in areas of apparent organic contamination, determining that the Santo Domingo Lagoon demonstrates an "excellent" indicator. Keywords: water, analysis, bioindicators, quality, indices, lagoon.

Serum Amylase Activity in Children Living with HIV-1 at the Charles de Gaulle Pediatric University Hospital in Ouagadougou

Biological monitoring is an essential part of the management of HIV infection. The aim of this study was to assess serum amylase activity during follow-up of children living with HIV-1 (CLHIV-1) at the Charles de Gaulle Pediatric University Hospital (CHUP-CDG). This was a descriptive and analytical cross-sectional study, with retrospective data collection from January 1, 2020 to December 31, 2022. Patients under 15 years of age who were being monitored for HIV-1 at CHUP-CDG and who had undergone a serum amylase assay during the study period were included. A total of 746 patients have been included, with a M/F sex ratio of 0.91 and a mean age of 8.52±4.08 years. Among CLHIV-1, 88.05% had a TCD4 lymphocyte count &amp;gt; 500/mm&amp;lt;sup&amp;gt;3&amp;lt;/sup&amp;gt; and 60.32% an undetectable plasma viral load (PVL). The incidence of hyperamylasemia in the study population was 57.64%. Hyperamylasemia was significantly more frequent in children aged 0-2 years (&amp;lt;i&amp;gt;p&amp;lt;0.00001&amp;lt;/i&amp;gt;), in patients with a high PVL (&amp;lt;i&amp;gt;p=0.0016&amp;lt;/i&amp;gt;) and in those on the protocol combining two nucleoside reverse transcriptase inhibitors with a protease inhibitor. Several abnormalities in serum amylase activity were detected in CLHIV-1 during the course of the study. Clinical correlation and adequate follow-up of these abnormalities are essential to reduce the morbidity and mortality associated with pancreatic damage in people living with HIV.

Time-varying coding digital double-layered Huygens' metasurface for high-efficiency harmonic frequency conversion

Time-varying metasurfaces offer an efficient means of controlling nonlinear harmonics by manipulating component geometries and modulating signals. This ability renders them valuable across various fields, such as wireless communication, radar sensing, and biological monitoring. However, most of the energy in time-varying metasurfaces is concentrated in the fundamental wave, as well as scattered at various harmonic orders, which reduces the energy efficiency at the desired harmonic. Existing approaches have employed time-varying coding digital metasurfaces to achieve efficient harmonic conversion but are primarily designed for reflection. Reflection-based designs require a feed source to excite the metasurface, which can cause certain shielding effects and limit their application in specific scenarios. Thus, designing transmissive time-varying coding digital metasurfaces for efficient harmonic conversion is currently an urgent problem that needs to be addressed. To solve this problem, this paper develops a time-varying coding digital double-layered Huygens' metasurface, which achieves efficient conversion of the desired transmitted harmonics. The unit structure of the metasurface consists of a pair of reverse-symmetric split rings located on the upper and lower sides of a dielectric substrate, enabling nearly non-reflective Huygens' resonance. Based on a continuous periodic phase modulation strategy, we achieved efficient conversion of transmitted harmonics by loading a time-varying voltage (phase) modulation signal with a 5-bit resolution bit width onto the designed double-layered Huygens' metasurface. This study presents a solution for designing a transmissive time-varying coding digital metasurface to achieve efficient conversion of harmonics, thereby enhancing the application capabilities of time-varying coding digital metasurfaces.

Tunable C4-Symmetry-Broken Metasurfaces Based on Phase Transition of Vanadium Dioxide (VO2).

Coupling is a ubiquitous phenomenon observed in various systems, which profoundly alters the original oscillation state of resonant systems and leads to the unique optical properties of metasurfaces. In this study, we introduce a terahertz (THz) tunable coupling metasurface characterized by a four-fold rotation (C4) symmetry-breaking structural array achieved through the incorporation of vanadium dioxide (VO2). This disruption of the C4 symmetry results in dynamically controlled electromagnetic interactions and couplings between excitation modes. The coupling between new resonant modes modifies the peak of electromagnetic-induced transparency (EIT) within the C4 symmetric metasurfaces, simulating the mutual interference process between modes. Additionally, breaking the C4 symmetry enhances the mirror asymmetry, and imparts distinct chiral properties in the far-field during the experimental process. This research demonstrates promising applications in diverse fields, including biological monitoring, light modulation, sensing, and nonlinear enhancement.

Long-term complications of permanent hypoparathyroidism in adults: prevalence and associated factors.

Patients with Chronic hypoparathyroidism (CHPT) receiving conventional treatment are exposed to several long-term complications including basal ganglia calcifications, posterior subcapsular cataract, kidney stones, and renal insufficiency. The aim of this study was to assess the prevalence and the associated factors of these complications in patients with CHPT. We conducted a cross-sectional study including 58 patients with CHPT. All participants underwent physical examination, biochemical assessment (total serum calcium, serum phosphorus, serum albumin, intact-PTH, serum magnesium, 25-hydroxy-vitamin D, serum creatinine, thyroid stimulating hormone (TSH), and 24-hour urinary calcium), slit lamp examination, brain computed tomography scan (CT-scan), and renal ultrasound. Participants had a mean age of 52.6 ± 16.4 years and a gender ratio (women/men) of 3.5. Fahr syndrome, cataract, urolithiasis, and renal failure were found in 55%, 62%, 12%, and 17% of cases, respectively. CHPT duration >15 years (Adjusted-OR = 43.1, 95-CI: 2.63-703.06, p = 0.008) and poor adherence to treatment (Adjusted-OR = 8.04, 95%-CI: 1.52-42.42, p = 0.014) were independently associated with the risk of Fahr syndrome. Age >55 years (adjusted-OR = 5.07, 95-CI: 1.10-23.42, p = 0.037), disease duration >15 years (adjusted-OR = 20.21, 95-CI: 1.54-265.84, p = 0.022), and magnesium level <0.8 mmol/l (adjusted-OR = 36.46, 95-CI: 3.75-354.08, p = 0.002) were independently associated with the risk of subcapsular cataract. Only hypercalciuria (Adjusted-OR = 21.27, 95-CI: 2.31-195.91, p = 0.007) was an independent risk factor for kidney stones. Renal failure was not associated with kidney stones (p = 1). However, creatinine clearance was negatively correlated with age (r = -0.784; p < 10-3) and disease duration (r = -0.352; p = 0.007). Our results revealed high prevalences of neurological, ocular, and renal complications in patients with CHPT and emphasized the importance of regular biological monitoring, therapeutic adjustments, screening, and adherence to treatment in the prevention of these complications.