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Abstract For a continuous healthcare or environmental monitoring system, it is essential to reliably sense the analyte concentration reported by electrochemical sensors. However, environmental perturbation, sensor drift, and power-constraint make reliable sensing with wearable and implantable sensors difficult. While most studies focus on improving sensor stability and precision by increasing the system’s complexity and cost, we aim to address this challenge using low-cost sensors. To obtain the desired accuracy from low-cost sensors, we borrow two fundamental concepts from communication theory and computer science. First, inspired by reliable data transmission over a noisy communication channel by incorporating redundancy, we propose to measure the same quantity (i.e., analyte concentration) with multiple sensors. Second, we estimate the true signal by aggregating the output of the sensors based on their credibility, a technique originally developed for “truth discovery” in social sensing applications. We use the Maximum Likelihood Estimation to estimate the true signal and the credibility index of the sensors over time. Using the estimated signal, we develop an on-the-fly drift-correction method to make unreliable sensors reliable by correcting any systematic drifts during operation. Our approach can determine solution pH within 0.09 pH for more than three months by detecting and correcting the gradual drift of pH sensors as a function of gamma-ray irradiation. In the field study, we validate our method by measuring nitrate levels in an agricultural field onsite over 22 days within 0.06 mM of a high-precision laboratory-based sensor. We theoretically demonstrate and numerically validate that our approach can estimate the true signal even when the majority (~ 80%) of the sensors are unreliable. Moreover, by restricting wireless transmission to high-credible sensors, we achieve near-perfect information transfer at a fraction of the energy cost. The high-precision sensing with low-cost sensors at reduced transmission cost will pave the way for pervasive in-field sensing with electrochemical sensors. The approach is general and can improve the accuracy of any field-deployed sensors undergoing drift and degradation during operation.

Inflammatory bowel disease (IBD) has become alarmingly prevalent in the last two decades affecting 6.8 million people worldwide with a starkly high relapse rate of 40% within 1 year of remission. Existing visual endoscopy techniques rely on subjective assessment of images that are error-prone and insufficient indicators of early-stage IBD, rendering them unsuitable for frequent and quantitative monitoring of gastrointestinal health necessary for detecting regular relapses in IBD patients. To address these limitations, we have implemented a miniaturized smart capsule (2.2 cm × 11 mm) that allows monitoring reactive oxygen species (ROS) levels as a biomarker of inflammation for quantitative and frequent profiling of inflammatory lesions throughout the gastrointestinal tract. The capsule is composed of a pH and oxidation reduction potential (ORP) sensor to track the capsule's location and ROS levels throughout the gastrointestinal tract, respectively, and an optimized electronic interface for wireless sensing and data communication. The designed sensors provided a linear and stable performance within the physiologically relevant range of the GI tract (pH: 1–8 and ORP: −500 to +500 mV). Additionally, systematic design optimization of the wireless interface electronics offered an efficient sampling rate of 10 ms for long-running measurements up to 48 h for a complete evaluation of the entire gastrointestinal tract. As a proof-of-concept, the capsule the capsule's performance in detecting inflammation risks was validated by conducting tests on in vitro cell culture conditions, simulating healthy and inflamed gut-like environments. The capsule presented here achieves a new milestone in addressing the emerging need for smart ingestible electronics for better diagnosis and treatment of digestive diseases.

Few inverse data envelopment analysis (DEA) models have incorporated non-discretionary measures based on radial efficiency values. However, the efficiency may be miscounted in radial approaches when some non-zero slacks appear. Furthermore, there is scant research on inverse DEA to estimate performance measures in the restaurant industry. Accordingly, this research proposes models based on non-radial DEA to analyze the efficiency and output changes of some Iranian restaurants while also presenting non-discretionary measures. Actually, in the company of non-discretionary factors, a non-radial DEA approach and its inverse problem are introduced to assess the performance and estimate the outputs for the modifications of inputs, respectively, while the inefficiency levels are maintained (and when they are preserved or decreased). The inefficiency of each discretionary input and output is specified using the presented non-radial DEA approach, and output targets are determined through inverse non-radial DEA with non-discretionary inputs. The results show containing non-discretionary data leads to more rational determinations through non-radial DEA-founded problems. This research presents analytic insights into the resources of inefficiency and output targets of entities with non-discretionary data, such as restaurants.

Abstract The problematic combination of a rising prevalence of skin and soft tissue infections and the growing rate of life-threatening antibiotic resistant infections presents an urgent, unmet need for the healthcare industry. These evolutionary resistances originate from mutations in the bacterial cell walls which prevent effective diffusion of antibiotics. Gram-negative bacteria are of special consideration due to the natural resistance to many common antibiotics due to the unique bilayer structure of the cell wall. The system developed here provides one solution to this problem through a wearable therapy that delivers and utilizes gaseous ozone as an adjunct therapy with topical antibiotics through a novel dressing with drug-eluting nanofibers (NFs). This technology drastically increases the sensitivity of Gram-negative bacteria to common antibiotics by using oxidative ozone to bypass resistances created by the bacterial cell wall. To enable simple and effective application of adjunct therapy, ozone delivery and topical antibiotics have been integrated into a single application patch. The drug delivery NFs are generated via electrospinning in a fast-dissolve PVA mat without inducing decreasing gas permeability of the dressing. A systematic study found ozone generation at 4 mg/h provided optimal ozone levels for high antimicrobial performance with minimal cytotoxicity. This ozone treatment was used with adjunct therapy delivered by the system in vitro. Results showed complete eradication of Gram-negative bacteria with ozone and antibiotics typically used only for Gram-positive bacteria, which showed the strength of ozone as an enabling adjunct treatment option to sensitize bacteria strains to otherwise ineffective antibiotics. Furthermore, the treatment is shown through biocompatibility testing to exhibit no cytotoxic effect on human fibroblast cells.

Abstract Precision Agriculture (PA) is an integral component of the contemporary agricultural revolution that focuses on enhancing food productivity in proportion to the increasing global population while minimizing resource waste. While the recent advancements in PA, such as the integration of IoT (Internet of Things) sensors, have significantly improved the surveillance of field conditions to achieve high yields, the presence of batteries and electronic chips makes them expensive and non-biodegradable. To address these limitations, for the first time, we have developed a fully Degradable Intelligent Radio Transmitting Sensor (DIRTS) that allows remote sensing of subsoil volumetric water using drone-assisted wireless monitoring. The device consists of a simple miniaturized resonating antenna encapsulated in a biodegradable polymer material such that the resonant frequency of the device is dependent on the dielectric properties of the soil surrounding the encapsulated structure. The simple structure of DIRTS enables scalable additive manufacturing processes using cost-effective, biodegradable materials to fabricate them in a miniaturized size, thereby facilitating their automated distribution in the soil. As a proof-of-concept, we present the use of DIRTS in lab and field conditions where the sensors demonstrate the capability to detect volumetric water content within the range of 3.7–23.5% with a minimum sensitivity of 9.07 MHz/%. Remote sensing of DIRTS can be achieved from an elevation of 40 cm using drones to provide comparable performance to lab measurements. A systematic biodegradation study reveals that DIRTS can provide stable readings within the expected duration of 1 year with less than 4% change in sensitivity before signs of degradation. DIRTS provides a new steppingstone toward advancing precision agriculture while minimizing the environmental footprint.

Abstract The development of flexible hybrid electronics (FHEs) with high‐throughput integration of electrical components onto digitally printed circuits has a wide range of applications, such as asset tracking, wearable electronics, and structural health monitoring. However, one of the major challenges with FHEs is the process of soldering the electrical components onto a printed circuit while having minimal thermal damage to the printed traces and their temperature‐sensitive polymeric substrates. Here, the possibility of utilizing near‐infrared (NIR) technology as a nondestructive photonic approach for rapid soldering and mounting electrical components onto printed circuits while keeping the polymer substrate at a relatively low temperature during the soldering process is investigated. Results of this systematic study show that FHEs prepared with the optimized NIR processing conditions produce the desired reflow of solder with effective electrical connection and metallic bonding of electrical components onto the conductive traces with excellent mechanical stability (no failure even after 1000 cycles of bending). Furthermore, using this technique and as a proof of concept, the fabrication of a wearable FHE device that provides a remote assessment of the wound exudate absorption in dressings and notifies caregivers of the appropriate time to change the dressing is demonstrated.

Mashhad, the second-most populous city in Iran, is situated in a hot and dry climate, and climate change has led to the temperature in this city climbing in recent years. This study's objective is to design a green roof per the region's hot and arid climate to maximize plant growth. The thermal comfort of citizens is explored in this study. A questionnaire was developed and distributed to 406 individuals for this experiment. The frequency measurement test was utilized to do statistical computations in order to quantify the sample's frequency, while the chi-square test (chi-square) was utilized to assess the relationship between class and rank variables. Residents from thirteen distinct neighborhoods are selected at random and proportionally. The findings of this study indicate that the positive effects of green roofs extend beyond the city of Mashhad and have a global impact. When green roof development is performed on a large scale in a city or region, many of the negative consequences of environmental change over the past several decades will be offset. By putting green roofs on buildings and all over cities, the effects of climate change are being fought off better.However, a scientific and preferred approach for installing and cultivating green roofs in Mashhad is of greater importance. Using the data analysis of the questionnaire, the desires, interests, and concerns of Mashhad's population were identified. The following development plan shows how the green roof field can grow desirably and acceptably.

Dermal wound infections are a rising source of morbidity and mortality in patients worldwide as new and worsening complications reduce the efficacy of traditional treatments. These challenges in wound care are increasingly caused by comorbidities such as obesity and diabetes as well as surging rates of antibiotic resistance. As a result, there is an urgent need for alternative treatment options. Gaseous ozone has shown great promise as a potential new treatment for infected dermal wounds. In this brief review of current wound therapy techniques found in the literature, an in-depth discussion of the mechanisms, benefits, and results of topical ozone gas as a therapy for infected dermal wounds is presented. This includes studies of ozone applied to wounds performed in vitro, in vivo, and clinical settings, as well as the use of ozone as an adjunct therapy for increasing the efficacy of traditional treatments. The overwhelming evidence suggests that ozone exhibits significant antimicrobial properties and has been shown to promote wound healing factors, especially when applied between 5–60 ppm. As such, this promising alternative therapy warrants a significant investment of time and resources to fully utilize ozone as an effective treatment against antibiotic resistant bacteria and other rising challenges in wound treatment.

Wound-associated infections are a significant and rising health concern throughout the world owing to aging population, prevalence of diabetes, and obesity. In addition, the rapid increase of life-threatening antibiotic resistant infections has resulted in challenging wound complications with limited choices of effective therapeutics. Recently, topical ozone therapy has shown to be a promising alternative approach for treatment of non-healing and infected wounds by providing strong antibacterial properties while stimulating the local tissue repair and regeneration. However, utilization of ozone as a treatment for infected wounds has been challenging thus far due to the need for large equipment usable only in contained, clinical settings. This work reports on the development of a portable topical ozone therapy system comprised of a flexible and disposable semipermeable dressing connected to a portable and reusable ozone-generating unit via a flexible tube. The dressing consists of a multilayered structure with gradient porosities to achieve uniform ozone distribution. The effective bactericidal properties of the ozone delivery platform were confirmed with two of the most commonly pathogenic bacteria found in wound infections, Pseudomonas aeruginosa and Staphylococcus epidermidis. Furthermore, cytotoxicity tests with human fibroblasts cells indicated no adverse effects on human cells.

In this paper, we review new and emerging energy sources for wireless implantable microdevices. After a brief historical background, we review the developments in power sources in the decades following the pioneering works of Zworykin and Mackay in the late 1950s. These include deployment of lithium batteries and inductive powering in the 1970s, which resulted in significant growth and commercialization of implantable medical devices, such as cardiac pacemakers and cochlear implants. Recent research in nanoscale materials for energy generation has created intriguing possibilities for next generation implantable power sources in the form of flexible and biodegradable batteries and supercapacitors. In addition, energy harvesting/remote powering from various environmental physical and chemical sources within the body utilizing nanoscale materials can also offer unique possibilities for autonomous implantable microscale and nanoscale devices.

Summary: Among various solid tumours, gastric cancer (GC) is one of the leading causes of cancer‐related deaths worldwide. Expansion into the peritoneal cavity, which results from dissemination of diffuse cancer cells, is the main cause of mortality in gastric adenocarcinoma patients. Therefore, investigation of putative biomarkers involved in metastasis is prerequisite for GC management. In an effort to discover potential tumour markers associated with peritoneal metastasis of GC, a semi‐synthetic human scFv library (Tomlinson I) was used to isolate novel antibody fragments recognizing MKN‐45, a poorly differentiated diffuse gastric adenocarcinoma cell line. Four rounds of subtractive selection each consisting of extensive pre‐absorption of phage library with NIH‐3T3 murine embryonic fibroblasts and AGS (a well‐differentiated intestinal gastric adenocarcinoma) cell line were carried out prior to positive selection on MKN‐45 target cells. ELISA‐based screening of 192 phage‐displayed scFv clones indicated 21 high‐affinity binders with specific staining of MKN‐45 compared with AGS cells. Diversity analysis of the selected phage‐scFvs resulted in five distinct sequences with multiple frequency. Further analysis by ELISA and flow cytometry verified three clones that specifically recognized MKN‐45 cells. Liquid chromatography‐mass spectrometry analysis of the scFv‐immunoprecipitated proteins has led to identification of c‐Met, HSP90 α and HSP90 β as candidate biomarkers associated with diffuse GC. Immunohistochemistry revealed the capability of purified scFvs to differentiate diffuse and intestinal gastric adenocarcinoma. Taken together, the isolated MKN‐45‐specific scFv fragments and their cognate antigens would be beneficial in screening and management as well as targeting and therapy of the diffuse gastric adenocarcinoma. [ABSTRACT FROM AUTHOR]

Purpose: Generation of antibodies which potentially discriminate between malignant and healthy cells is an important prerequisite for early diagnosis and treatment of gastric cancer (GC). Comparative analysis of cell surface protein landscape will provide an experimental basis for biomarker discovery, which is essential for targeted molecular therapies. This study aimed to isolate phage-displayed antibody fragments recognizing cell surface proteins, which were differently expressed between two closely related GC cell lines, namely AGS and MKN-45. Methods: We selected and screened a semisynthetic phage-scFv library on AGS, MKN-45, and NIH-3T3 cell lines by utilizing a tailored selection scheme that was designed to isolate phagescFvs that not only recognize the differentiated AGS cells but also distinguish them from NIH- 3T3 fibroblasts and the poorly differentiated MKN-45 cells. Results: After four rounds of subtractive whole cell panning, 14 unique clones were identified by ELISA screening and nucleotide sequencing. For further characterization, we focused on four phage-scFvs with strong signals in screening, and their specificity was confirmed by cell-based ELISA. Furthermore, the selected phage-scFvs were able to specifically stain AGS cells with 38.74% (H1), 11.04% (D11), 76.93% (G11), and 69.03% (D1) in flow cytometry analysis which supported the ability of these phage scFvs in distinguishing AGS from MKN-45 and NIH-3T3 cells. Conclusion: Combined with other proteomic techniques, these phage-scFvs can be applied to membrane proteome analysis and, subsequently, identification of novel tumor-related antigens mediating proliferation and differentiation of cells. Furthermore, such antibody fragments can be exploited for diagnostic purposes as well as targeted drug delivery of GC. [ABSTRACT FROM AUTHOR]

The first Zagreb eccentricity index E1℧ is the sum of square of eccentricities of the vertices, and the second Zagreb eccentricity index E2℧ is the sum of product squares of the eccentricities of the vertices. A linked graph G is called a cactus if any two of its cycles share only one vertex. In other words, there are no two independent cycles that share an edge. Cactus graphs are also known as “block graphs” or “sensitized graphs.” They are closely related to chordal graphs and can be used to represent various types of networks, including communication networks and road networks. In this contribution, E1℧ and E2℧ values of cacti with k pendant vertices and k cycles, respectively, are considered. We determine the minimum E1,E2 indices for n order cacti with k pendant vertices and k cycles.

A commercially available Janus paper with one hydrophobic (polyethylene-coated) face and a hygroscopic/hydrophilic one is irreversibly bonded to a polydimethylsiloxane (PDMS) substrate incorporating microfluidic channels via corona discharge surface treatment. The bond strength between the polymer-coated side and PDMS is characterized as a function of corona treatment time and annealing temperature/time. A maximum strength of 392 kPa is obtained with a 2 min corona treatment followed by 60 min of annealing at 120 °C. The water contact angle of the corona-treated polymer side decreases with increased discharge duration from 98° to 22°. The hygroscopic/hydrophilic side is seeded with human lung fibroblast cells encapsulated in a methacrylated gelatin (GelMA) hydrogel to show the potential of this technology for nutrient and chemical delivery in an air–liquid interface cell culture. [ABSTRACT FROM AUTHOR]

Fabricating highly stretchable and robust electrical interconnects at low-cost remains an unmet challenge in stretchable electronics. Previously reported stretchable interconnects require complicated fabrication processes with resulting devices exhibiting limited stretchability, poor reliability, and large gauge factors. Here, we demonstrate a novel sew-and-transfer method for rapid fabrication of low-cost, highly stretchable interconnects. Using a commercial sewing machine and double-thread stitch with one of the threads being water soluble polyvinyl alcohol (PVA), thin zigzag-pattern metallic wires are sewn into a polymeric film and are subsequently transferred onto a stretchable elastomeric substrate by dissolving PVA in warm water. The resulting structures exhibit extreme stretchability (exceeding 500% strain for a zigzag angle of 18 °) and robustness (capable of withstanding repeated stretch-and-release cycles of 15000 at 110% strain, 50000 at 55% strain, and  > 120000 at 30% strain without any noticeable change in resistance even at maximum strain levels). Using this technique, we demonstrate a stretchable inductive strain sensor for monitoring balloon expansion in a Foley urinary catheter capable of detecting the balloon diameter change from 9 mm to 38 mm with an average sensitivity of 4 nH/mm. [ABSTRACT FROM AUTHOR]

Purpose: Generation of antibodies which potentially discriminate between malignant and healthy cells is an important prerequisite for early diagnosis and treatment of gastric cancer (GC). Comparative analysis of cell surface protein landscape will provide an experimental basis for biomarker discovery, which is essential for targeted molecular therapies. This study aimed to isolate phage-displayed antibody fragments recognizing cell surface proteins, which were differently expressed between two closely related GC cell lines, namely AGS and MKN-45. Methods: We selected and screened a semisynthetic phage-scFv library on AGS, MKN-45, and NIH-3T3 cell lines by utilizing a tailored selection scheme that was designed to isolate phagescFvs that not only recognize the differentiated AGS cells but also distinguish them from NIH3T3 fibroblasts and the poorly differentiated MKN-45 cells. Results: After four rounds of subtractive whole cell panning, 14 unique clones were identified by ELISA screening and nucleotide sequencing. For further characterization, we focused on four phage-scFvs with strong signals in screening, and their specificity was confirmed by cell-based ELISA. Furthermore, the selected phage-scFvs were able to specifically stain AGS cells with 38.74% (H1), 11.04% (D11), 76.93% (G11), and 69.03% (D1) in flow cytometry analysis which supported the ability of these phage scFvs in distinguishing AGS from MKN-45 and NIH-3T3 cells. Conclusion: Combined with other proteomic techniques, these phage-scFvs can be applied to membrane proteome analysis and, subsequently, identification of novel tumor-related antigens mediating proliferation and differentiation of cells. Furthermore, such antibody fragments can be exploited for diagnostic purposes as well as targeted drug delivery of GC.

Introduction: To investigate the prevalence of enteroaggregative Escherichia coli (EAEC) in children < 10 years with a diagnosis of gastroenteritis by multiplex polymerase chain reaction (MPCR). Methods: A total of 303 diarrheal stool samples from patients admitted to Tabriz children¢s hospital (the referral center in East Azerbaijan province of Iran) with diagnosis of gastroenteritis were enrolled in cross-sectional study for detection of three virulence genes using MPCR. Results: EAEC infection was found in 55 cases (18.2%). aspU gene was the most frequently detected gene (51 of 55). Of 55 EAEC 27 (49.1%) had only aspU gene, 4 (7.3%) just pCVD432 gene and 24 (43.6%) samples had both genes (aspU and pCVD432) simultaneously. There was no sample harboring aggR gene. Prevalence of EAEC among girls and boys were 14.6% (18/123) and 20.5% (37/180), respectively. Prevalence of EAEC according to the age group was 17% for 0-5 years (42 of 247) and 23.2% for 5-10 years (13 of 56). There was no significant association between prevalence of EAEC and the age groups and also the gender of the patients (P > 0.05). Conclusion: The present study revealed the high prevalence of EAEC in children with diarrhea in this region that should be more considered in preventing, diagnosis and treatment strategies. We conclude that using multiple virulence genes simultaneously for detection of this strain is necessary to gain reliable results with pointing to aspU as preferred gene for detecting EAEC when diagnosis based on the presence of one virulence marker. To the best of our knowledge, this is the first report on the prevalence of EAEC strains in the northwest of Iran.