Human Body Research Articles

Oxaluria in inflammatory bowel diseases (review)

AIM: to analyse and synthesize Russian and foreign literature, to get acquainted with the concept of oxaluria, its types, transport mechanisms of oxalate transport in the intestine and the relationship between hyperoxaluria and inflammatory bowel diseases in order to identify possible options for therapeutic action on the mechanisms of development of these pathologies. MATERIALS AND METHODS: the literature review was based on the Internet data, including bibliographic directories, books, journals, and original articles. The literature sources used for the article reflect the essence of the described problem to the fullest extent possible and can be useful for both practicing physicians and students of medical universities. RESULTS: the gastrointestinal tract through epithelial transport of oxalate plays an exclusive role in oxalate homeostasis and hyperoxaluria. Metabolism of dietary oxalate and the formation of endogenous oxalate, its secretion, absorption, transport and biodegradation by intestinal microflora may influence the excretion of this compound by the kidneys. Knowledge of the interrelated relationships of the gut-kidney axis, mechanisms of transport, transport and biodegradation of oxalate, especially in inflammatory bowel disease, is of great importance for understanding the pathophysiology of hyperoxaluria as a risk factor for urinary stone formation with a point of pharmacological action in the gut. This literature review introduces the concept and forms of oxaluria, shows the classification of oxaluria, describes each form, and broadly explains the metabolism and mechanisms of oxalate transport in the human body. Special attention is given to intestinal hyperoxaluria and anion exchangers belonging to the large multifunctional SLC26 gene family, most of which are expressed throughout the gastrointestinal tract. The authors emphasise their current role in intestinal oxalate transport, as well as methods of possible drug action on the mechanisms of hyperoxaluria. CONCLUSION: a multidisciplinary approach is needed to address the problems of intestinal hyperoxaluria and, consequently, the treatment of urolithiasis. The role of newly identified intestinal and renal anion exchangers is not fully understood, hence the targets and mechanisms of action on these types of exchangers with the possibility of preventing the development of urolithiasis are not fully understood. Further randomised studies on the problem under investigation are needed.

Metropolitan metamorphosis: posthuman transformations in the urbanised world of ‘Good Hunting’

ABSTRACT The present paper takes a critical posthumanist lens to study the consequences of rapid urbanisation of the Chinese landscape as presented in the short story ‘Good Hunting’, by Ken Liu. One of the main characters in the story is Yan, a huli jing (fox-spirit), whose ability to switch between her fox and human forms is severely impaired by the loss of remnant nature in China, and the subsequent erosion of the qi from the soil. It is not just the natural landscape that undergoes a transformation during urbanisation – the remnants of nature do not remain untouched by this process. Beings like Yan, who continue to inhabit the place that used to be their home, do not remain the same that they were pre-urbanisation. The city changes them, moulds them in ways hitherto inconceivable, and they undergo this transmogrification of their bodies and their self in order to survive. The article draws out the historical relationship between urban spaces and (post)human bodies, with a specific focus on the Chinese body, drawing parallels between the ideals associated with the city and juxtaposing them with what it means to be posthuman. The paper also interrogates Yan’s status as a liminal entity before and after Hong Kong’s transformation, and her use of liminality as a survival strategy.

Sensibility in the world of science and gendered society: the ethics and aesthetics of skin in The Skin I Live In

ABSTRACT This paper focuses on the aesthetical and ethical representations of skin in Pedro Almodóvar’s The Skin I Live In (2011). By emphasising the interconnectedness of the skin as an expressive interface mediating between the inner self and the material world, this paper examines how the image of skin extends beyond the visual aesthetics to engage viewers in a haptic sense. I argue that the haptic experience, when actively engaged, can transcend bodily suffering from unjust treatment, charging moving images with ethical consideration and envisioning alternative human bonds in a posthuman condition. By engaging with phenomenological concepts of flesh, intersubjectivity, and interobjectivity, this paper criticises the mistreatment of beings in the scientific field and the objectification of human bodies to sustain a gendered and patriarchal structure. Instead of solely attributing abusive and controlling masculinity and the oppression of women to the patriarchy, it is essential to go beyond traditional categories of male/female and masculinity/femininity and examine the modern systems that excessively alienate human beings. The paper proposes that an individual’s existence precedes social and political identification and advocates for a dynamic way to recognise and describe the process of becoming-body as it continuously undergoes qualitative changes through lived experiences.

‘Who am I now?’ the lived experiences and identity construction of individuals following bariatric surgery

ABSTRACT Mediatised standards of beauty in contemporary western societies contribute to stigma and discrimination of individuals labelled ‘obese’ by medical professionals. Most people who undergo weight-reduction treatments, including bariatric surgery, choose it due to serious health conditions, often unable to lose weight in any other way. However, they are commonly constructed as ‘cheaters’ and blamed for lacking will and self-control. Cultural beliefs demonising fat and fat people produce the perceptions of an inferior identity, often leading to internalised fatphobia among such individuals. This study investigates the lived experiences of 11 individuals after bariatric surgery using semi-structured interviews analysed via narrative framework. The findings demonstrate paradoxical effects bariatric surgery can have on identity, through a persistent ‘obese’ view of self and body perception challenges, indicating long-lasting harmful effects of symbolic violence these individuals experience due to stigmatisation and medicalisation of fat and highlighting hegemonic discourses inscribing normative views on human bodies.

Design and Optimization Analysis of an Adaptive Knee Exoskeleton

To solve the problem of undesired relative motion of human-machine interaction positions caused by misalignment of the human-machine joints rotation axis of the knee exoskeleton, this study designed an adaptive knee exoskeleton based on a gear-link mechanism (GLM) by considering the human body as a component of the exoskeleton mechanism. Simultaneously, the concept of the wearable area (WA) was proposed, which transformed the operation of aligning the exoskeleton rotation axis with the human knee joint rotation axis into a "face alignment point" in the sagittal plane, reducing the difficulty of aligning the human-machine joint rotation axis. In the kinematic analysis of GLM, the phenomenon of instantaneous movement of the central axis of the human knee joint was considered. Based on the kinematic model, the WA, velocity transfer ratio, and initial position static stiffness of GLM were analyzed. The NSGA-II optimization algorithm was used to optimize the size parameters of GLM, which increased the WA by 18.4%, the average velocity transfer ratio by 4.98%, and the average initial position static stiffness by 6.01%. Finally, the ability of the exoskeleton to absorb movement displacement (MD) was verified through simulation, and the good human-machine kinematic compatibility of the exoskeleton was verified through wearable tests conducted on the initial mechanism principle prototype.

Multifaceted Roles of Vitamin D for Diabetes: From Immunomodulatory Functions to Metabolic Regulations

Numerous studies have established associations between vitamin D and diabetes. The vitamin D receptor is widely distributed throughout the human body, including in pancreatic beta cells (β-cells), hepatocytes, and immune cells. Therefore, vitamin D’s effect on the risk, progression, or complications of diabetes may be mediated through various mechanisms. These include the regulation of insulin secretion or sensitivity and modulation of β-cell function and its immunomodulatory and anti-inflammatory effects. This review extensively explores the relationship between vitamin D status and diabetes, as well as the preventive or therapeutic effects of vitamin D supplementation on diabetes from human studies. Additionally, it examines in detail the impact of vitamin D on immune and inflammatory responses in the diabetic milieux and β-cell function to better understand the underlying mechanisms through which vitamin D influences diabetes.

Electrochemical sensing of vitamin B6 (pyridoxine) by adapted carbon paste electrode

The recent investigation targets to use adapted carbon paste (CP) with copper nanoparticles (CuNs) operating in a phosphate buffer (PBS) medium with a pH range of 5.0–8.0, to synthesize a novel, susceptible, and simple electrochemical sensor for the detection of one of the most important drugs, vitamin B6. Copper (Cu) is one of the most three common essential trace elements found in the bodies of both humans and animals, along with iron and zinc for all crucial physiological and biochemical functions. Its properties, which are assessed using a variety of methods including scanning electron microscopy (SEM), cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS), have also drawn a lot of attention recently. We considered the effects of pH, buffer, scan rate, interference, and calibration curve. The susceptible electrode's linear calibration curve encompassed concentration values between 8.88 and 1000.0 µM. The calculated limits of detection and quantification were 32.12 and 107.0 µM, respectively. Furthermore, this method was established in real human urine samples and drug validation which have been shown satisfactory results for vitamin B6 detection.

The mutant mouse resource and research center (MMRRC) consortium: the US-based public mouse repository system

AbstractNow in its 25th year, the Mutant Mouse Resource and Research Center (MMRRC) consortium continues to serve the United States and international biomedical scientific community as a public repository and distribution archive of laboratory mouse models of human disease for research. Supported by the National Institutes of Health (NIH), the MMRRC consists of 4 regionally distributed and dedicated vivaria, offices, and specialized laboratory facilities and an Informatics Coordination and Service Center (ICSC). The overarching purpose of the MMRRC is to facilitate groundbreaking biomedical research by offering an extensive repertoire of mutant mice that are essential for advancing the understanding of human physiology and disease. The function of the MMRRC is to identify, acquire, evaluate, characterize, cryopreserve, and distribute mutant mouse strains to qualified biomedical investigators around the nation and the globe. Mouse strains accepted from the research community are held to the highest scientific standards to optimize reproducibility and enhance scientific rigor and transparency. All submitted strains are thoroughly reviewed, documented, and validated using extensive scientific quality control measures. In addition, the MMRRC conducts resource-related research on cryopreservation, mouse genetics, environmental conditions, and other topics that enhance operations of the MMRRC. Today, the MMRRC maintains an archive of mice, cryopreserved embryos and sperm, embryonic stem (ES) cell lines, and murine hybridomas for nearly 65,000 alleles. Since its inception, the MMRRC has fulfilled more than 20,000 orders from 13,651 scientists at 8441 institutions worldwide. The MMRRC also provides numerous services to assist researchers, including scientific consultation, technical assistance, genetic assays, microbiome analysis, analytical phenotyping, pathology, cryorecovery, husbandry, breeding and colony management, infectious disease surveillance, and disease modeling. The ICSC coordinates MMRRC operations, interacts with researchers, and manages the website (mmrrc.org) and online catalogue. Researchers benefit from an expansive list of well-defined mouse models of disease that meet the highest scientific standards while submitting investigators benefit by having their mouse strains cryopreserved, protected, and distributed in compliance with NIH policies.

Twenty years of microplastics pollution research—what have we learned?

Twenty years after the first publication using the term microplastics, we review current understanding, refine definitions and consider future prospects. Microplastics arise from multiple sources including tires, textiles, cosmetics, paint and the fragmentation of larger items. They are widely distributed throughout the natural environment with evidence of harm at multiple levels of biological organization. They are pervasive in food and drink and have been detected throughout the human body, with emerging evidence of negative effects. Environmental contamination could double by 2040 and widescale harm has been predicted. Public concern is increasing and diverse measures to address microplastics pollution are being considered in international negotiations. Clear evidence on the efficacy of potential solutions is now needed to address the issue and to minimize the risks of unintended consequences.

Understanding the significance of oxygen tension on the biology of Plasmodium falciparum blood stages: From the human body to the laboratory

Plasmodium falciparum undergoes sequestration within deep tissues of the human body, spanning multiple organ systems with differing oxygen (O2) concentrations. The parasite is exposed to an even greater range of O2 concentrations as it transitions from the human to the mosquito host, suggesting a high level of plasticity as it navigates these different environments. In this review, we explore factors that may contribute to the parasite’s response to different environmental O2 concentrations, recognizing that there are likely multiple pieces to this puzzle. We first review O2-sensing mechanisms, which exist in other apicomplexans such as Toxoplasma gondii and consider whether similar systems could exist in Plasmodium. Next, we review morphological and functional changes in P. falciparum’s mitochondrion during the asexual-to-sexual stage transition and discuss how these changes overlap with the parasite’s access to O2. We then delve into reactive oxygen species (ROS) as ROS production is influenced by O2 availability and oxidative stress impacts Plasmodium intraerythrocytic development. Lastly, given that the primary role of the red blood cell (RBC) is to deliver O2 throughout the body, we discuss how changes in the oxygenation status of hemoglobin, the RBC’s O2-carrying protein and key nutrient for Plasmodium, could also potentially impact the parasite’s growth during intraerythrocytic development. This review also highlights studies that have investigated P. falciparum biology under varying O2 concentrations and covers technical aspects related to P. falciparum cultivation in the lab, focusing on sources of technical variation that could alter the amount of dissolved O2 encountered by cells during in vitro experiments. Lastly, we discuss how culture systems can better replicate in vivo heterogeneity with respect to O2 gradients, propose ideas for further research in this area, and consider translational implications related to O2 and malaria.

A Compact Low-profile Substrate Integrated Waveguide Wearable Filtenna for 5G Communication

Abstract The design and synthesis of a compact, low-profile, flexible substrate integrated waveguide (SIW) wearable filtering antenna (filtenna) along with two parasitic resonator patches has been proposed for 5G communication. For the purpose of minimizing circuit size, a half-mode rectangular-shaped substrate-integrated (HMRSI) cavity has been used as a resonating patch initially. HMRSI cavity has located in close proximity with two parasitic truncated corner patches serve as both the radiator and the final stage resonators, therefore optimizing the filtering performance and expanding the operating bandwidth. In order to enhance the roll-off rate, two different radiation nulls are achieved first at the upper band-edges & second at lower band-edges: one is produced by the parasitic patches’ interaction with the HMRSI cavity, while the other is created by the corner truncation and notching on the parasitic patches with defected ground. Filtenna design is guided by typical filter synthesis technology. A manufactured and measured optimized prototype has been done. The proposed flexible filtenna exhibits excellent out-of-band selectivity and measurement shows well agreement with simulated ones and attain an 8.2% fractional bandwidth (FBW), a max. realized gain of 6.1 dBi with a flat passband gain response. The proposed filtenna has also studied on human body and achieved low SAR which enables it on-body wearable filtenna.

Multitarget-Directed Ligands Hitting Serotonin Receptors: A Medicinal Chemistry Survey

Serotonin (5-hydroxytryptamine, 5-HT) is a ubiquitous neurotransmitter in the human body. In the central nervous system, 5-HT affects sleep, pain, mood, appetite, and attention, while in the peripheral nervous system, 5-HT modulates peristalsis, mucus production, and blood vessel dilation. Fourteen membrane receptors mediate 5-HT activity. In agreement with the crucial roles played by 5-HT, many drugs target 5-HT receptors (5-HTRs). Therefore, it is unsurprising that many efforts have been devoted to discovering multitarget-directed ligands (MTDLs) capable of engaging one or more 5-HTRs plus another target phenotypically linked to a particular disease. In this review, we will describe medicinal chemistry efforts in designing MTDLs encompassing activity for one or more 5-HTRs, starting with atypical antipsychotics and moving to dual 5-HT1AR/serotonin transporter ligands, 5-HT6R antagonists/acetyl cholinesterases inhibitors, and 5-HT4R agonists/acetyl cholinesterases inhibitors. We will also provide an outlook on the most recent efforts made in the field.

АНАЛИЗ КЛИМАТА И УЧЕТ ЕГО ОСОБЕННОСТЕЙ ПРИ ПРОЕКТИРОВАНИИ ЗДАНИЙ В Г.СИМФЕРОПОЛЬ

The purpose of the work is to develop typological recommendations for the designed buildings in Simferopol based on the architectural analysis of natural and climatic conditions. The study requires a detailed study of the temperature regime, temperature and humidity regime, temperature and wind regime, solar radiation and the bioclimatic characteristics of the construction area. Subject of the study: Human heat sensations are influenced by the interaction of factors such as temperature, solar radiation, air humidity and the speed of its movement. Depending on the combination of these factors, a person's heat perception can vary. Materials and methods: To achieve this goal, the following values were analyzed: average monthly outdoor temperature, relative humidity, wind speed and direction, and solar radiation. To assess the effect of climate on the human body, an equivalent-effective temperature and a normal equivalent temperature were calculated. AutoCAD and Microsoft Excel software were used to build the graphs. Results: The conducted research allowed us to determine the boundaries of comfort zones, the influence of the Simferopol climate on the human body. Conclusions: The results of the analysis of natural and climatic factors allow us to determine the typological requirements for the choice of architectural solutions: architectural planning, structural and engineering means of regulating the microclimate in buildings and buildings for Simferopol, taking into account its climate.

Probiotics as a potential tool for gynecological cancers prevention and therapy suport

The human body is host to a variety of microbial species that are essential for maintaining general health. About nine percent of these microbial species inhabit the urogenital tract. It is therefore important to establish a symbiotic relationship between the host’s immune system and the microbiota in this region. Disruptions of this symbiosis can contribute to the development of pelvic inflammatory disease (PID), bacterial vaginosis (BV), vaginal candidiasis and/or even gynaecological cancers by promoting the proliferation of infectious agents. The chemotherapeutic agents currently used in cancer treatment are associated with undesirable side effects. Therefore, there is an urgent need for antitumor agents that have minimal toxicity compared to conventional treatments. Furthermore, the use of drugs to prevent or alleviate the side effects of cervical cancer treatment could significantly improve the quality of life of patients undergoing such therapy. In this review, we focus our attention on the potential efficacy of probiotics in both the prevention and therapeutic intervention of neoplasms affecting the genital tract.

Bioinformatics-driven untargeted metabolomic profiling for clinical screening of methamphetamine abuse.

Amphetamine-type stimulants are very common, and their usage is becoming a very big social problem all over the world. Thousands of addicts encounter several health problems including mental, metabolic, behavioral and neurological disorders. In addition to these, there are several reports about the elevated risk of tendency on committing criminal cases by addicted persons. Hence, methamphetamine addiction is not only an individual health problem but also a social problem. In our study, we aimed to investigate the pathogenesis of chronic usage of methamphetamine via untargeted metabolomics approach. 38 plasma samples were carefully collected and extracted for untargeted metabolomics assay. A liquid-liquid extraction was performed to get as much metabolite as possible from the samples. After the extraction procedure, samples were transferred into vials and they were evaluated via time of flight mass spectrometry instrument. Significantly, altered metabolites were identified by the fold analysis and Welch's test between the groups. 42 different compounds were annotated regarding to data-dependent acquisition method. Pathway analysis were also performed to understand the hazardous effect of methamphetamine on human body. It has been reported that drug exposure may affect several metabolic pathways for amino acids, fats, energy metabolism and vitamins. An alternative bioinformatic model was also developed and validated in order to predict the chronic methamphetamine drug users in any criminal cases. This generated model passes the ROC curve analysis and permutation test and classify the controls and drug users correctly by evaluating the metabolic alterations between the groups.

Analysis of furin (FURIN) gene expression in the U-87 MG cell line as a potential target for gene inhibiting therapies in (auto-) immune diseases

Purpose: Furin is a proprotein convertase commonly found in the human body. The enzymatic activity of furin is necessary for the activation of numerous substrates including e.g. hormones and growth factors. Nevertheless, furin is involved in various pathological conditions caused by, among others, chronic inflammation. Therefore furin is considered as a potential target in autoimmune diseases therapy. We performed an experiment in which the expression of FURIN gene in U-87 MG astrocytoma cells was investigated. Additionally, this cell line contains some sequences coding human endogenous retroviruses (HERVs), including ERVW-1 and its receptor- SLC1A5. Deregulation of HERV expression has been observed in some neurodegenerative diseases as well as in inflammatory process. Material and Methods: Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot (WB) techniques were utilized for analysis. Phorbol 12-myristate 13-acetate (PMA) were used for cell stimulation. Short interfering RNAs (siRNA) were used for gene expression inhibition in U-87 MG cells in vitro. Results: Cell stimulation by PMA strongly increased FURIN expression, simultaneously downregulating ERVW-1 (p<0.01). Moreover addition of PMA significantly stimulates the autocatalytic action of cellular furin itself resulting in the dissociation of its propeptide that was clearly visible in a time-dependent manner. SiRNA-mediated expression inhibition of ERVW-1 and FURIN influenced the mRNA level for SLC1A5 (ASCT2) - primary syncytin-1 receptor, that was significantly lower. FURIN inhibition by siRNA caused strong upregulation of ERVW-1 expression (p<0.01). Conclusion: Our results showed that stimulation by PMA and inhibition expression by siRNA affects the expression of FURIN in U-87 MG astrocytoma cells. Moreover, furin shows a complex relationship on the expression of ERVW-1 and SLC1A5 genes, as well as on the form (precursor or mature) and the amount of the final translation products of the transcripts. The regulation of FURIN may pose a potential therapeutic strategy in the treatment of neurodegenerative diseases caused by autoimmunity.

Potential role of bacterial pathogens in the immunopathogenesis of ovarian cancer

The development of next-generation sequencing (NGS) techniques allowed conducting research with greater efficiency and determining the microbial pattern of niches in the human body that were previously considered sterile. Observed changes in the microbiome composition of patients with cancer lesions increasingly indicate the role of microorganisms in the tumour induction and progression. Overgrowth of certain pathogenic strains within the tissue may cause inflammation, which in its chronic form may lead to destabilization of host genome. Such changes may result in altering the expression of genes encoding proteins involved in significant metabolic pathways and promote pathogenic cell functions such as proliferation stimulation, apoptosis inhibition and modulation of inflammatory response. Consequently, these events may lead to tissue destruction, disruption of physiological processes and development of disease states including cancer. In light of emerging reports on the role of changes in the composition of the microbiota in tumorigenesis induction and the presence of pathogenic strains in the ovarian cancer (OC) tumour microenvironment (TME), the hypothesis of a potential role for bacteria in the pathogenesis of this cancer is also gaining interest. The following review presents a summary of scientific research indicating potential role of TME bacteria in the immunopathogenesis of OC.

Research on the Safety Design and Trajectory Planning for a New Dual Upper Limb Rehabilitation Robot

The increasing utilization of upper limb rehabilitation robots in rehabilitation therapy has brought to light significant safety concerns regarding their mechanical structures and control systems. This study focuses on a six degrees of freedom (DOF) upper limb rehabilitation robot, which has been designed with an emphasis on safety through careful consideration of its mechanical structure and trajectory planning. Various parameter schemes for the shoulder joint angles were proposed, and the robotic arm’s structure was developed by analyzing the spatial motion trajectories of the shoulder joint motor. This design successfully achieves the objective of minimizing the installation space while maximizing the range of motion. Additionally, an enhanced artificial field method is introduced to facilitate the planning of self-collision avoidance trajectories for dual-arm movements. This approach effectively mitigates the risk of collisions between the robotic arm and the human body, as well as between the two robotic arms, during movement. The efficacy of this method has been validated through experimental testing.

Transglutaminase–mucin binding dynamics in gastrointestinal mucus: Interfacial behaviour, thermodynamics and gelation mechanism

Transglutaminase, an enzyme present in epithelial cells and as a residual component in processed foods, is hypothesised to interact with gastrointestinal mucus, impacting its structure and function. To test the physical validity of this phenomenon, this study investigates the binding kinetics and thermodynamics between porcine gastric mucin (PGM) and microbial transglumatinse (TGM) in a model gastrointestinal mucus, followed by the rheological analysis of the resulting systems. At pH 7, TGM exhibited pronounced binding with the PGM interface, characterised by a high surface density (55.34 ± 1.86 µg/m−2) and a low dissociation constant (KD ∼ 4.03 ± 0.10 μM) as determined by surface plasma resonance (SPR). Conversely, at pH 3, TGM showed weak adhesion onto PGM, resulting in a less stable binding, reflected by a lower surface density (10.94 ± 0.67 µg/m−2) and a higher dissociation constant (KD ∼ 6.24 ± 0.22 μM). Regardless of the nature of interaction, the Hill coefficients (nH ≥ 1) indicated that the binding sites were markedly denser at pH 7 (1383.38 ± 46.47 pmol/m−2), than at pH 3 (273.68 ± 16.84 pmol/m−2). Fluorimetry analysis suggested temperature-dependent dynamic binding between PGM and TGM. The resulting Benesi – Hildebrand plots illustrated a linear correlation between PGM and increasing TGM concentration, suggesting a single-step interaction mechanism. The calculated thermodynamic parameters indicated spontaneous interaction between PGM and TGM (ΔG < 0) via endothermic (entropic) interactions (ΔH > 0). Notably, hydrophobic forces played a significant role in the network stabilisation of PGM−TGM complex (ΔS > 0). Rheometry analysis elucidates that the interaction maxima within TGM−PGM systems substantially elevate both shear viscosity (η), and the melting point (Tm), shifting from 6.75 ± 0.28 to 70.94 ± 2.21 (×10−3) Pa s (at 1 s−1), and 36.80 ± 0.80 to 48.20 ± 0.11 °C, respectively. Furthermore, the coexistence of these two macromolecular species results in a 3- to 4-fold dramatic increase in the viscoelastic moduli of the binary complex. These findings build a strong physicochemical basis for the interaction between TGM and PGM, with profound effects on the rhological behaviour of the latter; it also highlights the need to examine the biochemical/enzymatic aspects of said interactions, and their potential effects on mucosa and human physiology.

Shape optimization of a non-uniform piezoelectric bending beam for human knee energy harvester

Abstract Scavenging energy from the human body to provide a sustainable source for electronic devices has gained significant attention. Recently, scientists have focused on harnessing biomechanical energy from human motion. This study was dedicated to developing and optimizing a non-uniform piezoelectric bending beam-based human knee energy harvester. The bimorph non-uniform piezoelectric bending beam consisted of a non-uniform carbon fiber substrate and piezoelectric macro fiber composites. Compared to the uniform piezoelectric bending beam, the non-uniform piezoelectric beam can optimize the shape to improve the average strain, thus improving the energy harvesting efficiency. In this study, eight shape functions, including ellipse, sin, tanh, exponential function, parabola, trigonometric line, and bell curves, were investigated and optimized. The bell curve bending beam was selected and fabricated due to its good performance. Then, a benchmark platform was developed to test the deflection curve and reaction force when the nonuniform bending beam was compressed. Finally, to validate the design, experimental testing on three subjects was conducted when they were equipped with the harvester and walked on a treadmill. Testing results indicated that the non-uniform bending beam-based energy harvester can improve the energy harvesting efficiency by 28.57% compared to the uniform beam-based energy harvester. The output power can reach 18.94 mW when walking at 7.0 km h−1.