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Bacterial meningitis, an infection of the membranes (meninges) and cerebrospinal fluid (CSF) surrounding the brain and spinal cord, is one of the major causes of death and disability worldwide. Higher case-fatality rates and short survival times have been reported in developing countries. Hence, a quick, straightforward, and low-cost approach is in great demand for the diagnosis of meningitis. In this research, a microfluidic fully paper-based analytical device (μFPAD) integrated with loop-mediated isothermal amplification (LAMP) and ssDNA-functionalized graphene oxide (GO) nano-biosensors was developed for the first time for a simple, rapid, low-cost, and quantitative detection of the main meningitis-causing bacteria

Acephate is an organophosphorus pesticide (OP) that is widely used to control insects in agricultural fields such as in vegetables and fruits. Toxic OPs can enter human and animal bodies and eventually lead to chronic or acute poisoning. However, traditional enzyme inhibition and colorimetric methods for OPs detection usually require complicated detection procedures and prolonged time and have low detection sensitivity. High-sensitivity monitoring of trace levels of acephate residues is of great significance to food safety and human health. Here, we developed a simple method for ultrasensitive quantitative detection of acephate based on the carbon quantum dot (CQD)-mediated fluorescence inner filter effect (IFE). In this method, the fluorescence from CQDs at 460 nm is quenched by 2,3-diaminophenazine (DAP) and the resulting fluorescence from DAP at 558 nm is through an IFE mechanism between CQDs and DAP, producing ratiometric responses. The ratiometric signal

Paper-based microfluidic devices have undergone rapid development and offered a promising low-cost platform for disease diagnostics in poor-resource areas. Recently, paper-hybrid microfluidic devices have attracted much attention and been applied in various low-cost point-of-care testings, due to multiple merits derived from both paper and other substrates. This chapter summarizes the recent progress of low-cost paper and paper-hybrid microfluidic devices for rapid diagnostics of human diseases. The commonly used fabrication techniques are first introduced, and the applications of numerous paper and paper-hybrid microfluidic devices are then elaborated with an emphasis on rapid disease diagnostics in terms of the nature of biomolecules in three major categories, namely, protein-, gene-, and cell-based diagnostics. Both advantages and disadvantages of using these devices are discussed, followed by the perspectives for broad applications in low-cost diagnostics.

The present work addresses the recovery of rhenium from scrub liquor of molybdenite concentrate roasting fume and dust by solvent extraction method. According to the results, recovery of rhenium from the scrub liquor is not practical unless molybdenum is removed in advance. The extraction of molybdenum was carried out using a D2EHPA-TBP system which resulted in up to 99.8% Mo extraction in a two-stage solvent extraction at pH = 1 and O/A = 1. Up to 99.6% of Re was extracted subsequently using TOA in a single-stage extraction at pH = −0.3 and O/A = 1:20. The organic phase was stripped by ammonium hydroxide 32% and the resultant liquor was further subjected to evaporation as a result of which, an enriched purified solution was obtained. Ammonium perrhenate was precipitated from the enriched liquor by adjusting the pH to 6.5–7.

Cancer immunotherapy has achieved remarkable success over the past decade by modulating patients' own immune systems and unleashing pre-existing immunity. However, only a minority of cancer patients across different cancer types are able to benefit from immunotherapy treatment; moreover, among those small portions of patients with response, intrinsic and acquired resistance remains a persistent challenge. Because the tumor microenvironment (TME) is well recognized to play a critical role in tumor initiation, progression, metastasis, and the suppression of the immune system and responses to immunotherapy, understanding the interactions between the TME and the immune system is a pivotal step in developing novel and efficient cancer immunotherapies. With unique features such as low reagent consumption, dynamic and precise fluid control, versatile structures and function designs, and 3D cell co-culture, microfluidic tumor organoid-on-a-chip platforms that recapitulate key factors of the TME and the immune contexture have emerged as innovative reliable tools to investigate how tumors regulate their TME to counteract antitumor immunity and the mechanism of tumor resistance to immunotherapy. In this comprehensive review, we focus on recent advances in tumor organoid-on-a-chip platforms for studying the interaction between the TME and the immune system. We first review different factors of the TME that recent microfluidic in vitro systems reproduce to generate advanced tools to imitate the crosstalk between the TME and the immune system. Then, we discuss their applications in the assessment of different immunotherapies' efficacy using tumor organoid-on-a-chip platforms. Finally, we present an overview and the outlook of engineered microfluidic platforms in investigating the interactions between cancer and immune systems, and the adoption of patient-on-a-chip models in clinical applications toward personalized immunotherapy.

The contradictory and inefficient nature of urban public policy in Iranian historic cities has been subject to long debates in recent years, and has even led to disorganisation in the formation of dilapidated abandoned buildings (DABs). Under the current policies, three government agencies oversee the urban management in historic cities. The projects and processes that have yet to be implemented by these agencies are crucial for solving the problems associated with DABs. This research aims to investigate the current public policies of the essential key players and stakeholders in order to ameliorate the problem of DABs, which in the literature has been proven to be associated with socio-spatial disadvantage. A qualitative semi-structured enquiry was conducted, and urban public policies were evaluated on the basis of 19 in-depth interviews regarding the three historic cities of Yazd, Kashan and Isfahan. The results were analysed using cutting and sorting techniques, and thematic and critical narrative analysis. Several inadequacies in the current urban public policy were specified. This research could help decision-makers to create efficient management plans with respect to the reduction of DABs, an approach that can be considered efficient for the regeneration of life in historic cities.

As a class of crystalline porous materials, metal-organic frameworks (MOFs) have attracted increasing attention. Due to the nanoscale framework structure, adjustable pore size, large specific surface area, and good chemical stability, MOFs have been applied widely in many fields such as biosensors, biomedicine, electrocatalysis, energy storage and conversions. Especially when they are combined with aptamer functionalization, MOFs can be utilized to construct high-performance biosensors for numerous applications ranging from medical diagnostics and food safety inspection, to environmental surveillance. Herein, this article reviews recent innovations of aptamer-functionalized MOFs-based biosensors and their bio-applications. We first briefly introduce different functionalization methods of MOFs with aptamers, which provide a foundation for the construction of MOFs-based aptasensors. Then, we comprehensively summarize different types of MOFs-based aptasensors and their applications, in which MOFs serve as either signal probes or signal probe carriers for optical, electrochemical, and photoelectrochemical detection, with an emphasis on the former. Given recent substantial research interests in stimuli-responsive materials and the microfluidic lab-on-a-chip technology, we also present the stimuli-responsive aptamer-functionalized MOFs for sensing, followed by a brief overview on the integration of MOFs on microfluidic devices. Current limitations and prospective trends of MOFs-based biosensors are discussed at the end.

Phenolic lipids are multifunctional compounds which play an important biological role in the body. Their unique biologic functionality stems from their strong amphiphilic character which allows them to be incorporated in erythrocytes. Through membrane incorporation, these compounds exert their biological effects on neurons which are not modulated by hydrophilic compounds. These bioactive compounds are present in nature as secondary plant metabolites, and consequently their availability is limited, for dietary and medical purposes. In this review, the pathways and mechanisms associated with the pathogenesis of Alzheimer's disease will be described. In addition, the modulatory effects of phenolic lipids on these pathways and a list of several synthetic, semi synthetic and natural sources of phenolic lipids will be examined as having the potential to prevent or combat Alzheimer's disease.

Conventional systematically-administered drugs distribute evenly throughout the body, get degraded and excreted rapidly while crossing many biological barriers, leaving minimum amounts of the drugs at pathological sites. Controlled drug delivery aims to deliver drugs to the target sites at desired rates and time, thus enhancing the drug efficacy, pharmacokinetics, and bioavailability while maintaining minimal side effects. Due to a number of unique advantages of the recent microfluidic lab-on-a-chip technology, microfluidic lab-on-a-chip has provided unprecedented opportunities for controlled drug delivery. Drugs can be efficiently delivered to the target sites at desired rates in a well-controlled manner by microfluidic platforms via integration, implantation, localization, automation, and precise control of various microdevice parameters. These features accordingly make reproducible, on-demand, and tunable drug delivery become feasible. On-demand self-tuning dynamic drug delivery systems have shown great potential for personalized drug delivery. This review presents an overview of recent advances in controlled drug delivery using microfluidic platforms. The review first briefly introduces microfabrication techniques of microfluidic platforms, followed by detailed descriptions of numerous microfluidic drug delivery systems that have significantly advanced the field of controlled drug delivery. Those microfluidic systems can be separated into four major categories, namely drug carrier-free micro-reservoir-based drug delivery systems, highly integrated carrier-free microfluidic lab-on-a-chip systems, drug carrier-integrated microfluidic systems, and microneedles. Microneedles can be further categorized into five different types, i.e. solid, porous, hollow, coated, and biodegradable microneedles, for controlled transdermal drug delivery. At the end, we discuss current limitations and future prospects of microfluidic platforms for controlled drug delivery.

Ammonium perrhenate (APR) is an intermediate product in rhenium extraction process, by which it is possible to produce rhenium powder. The main purpose of this research is to investigate the behaviour of APR in different atmospheres as a part of reduction process. In this research, differential thermal analysis and thermo gravimetric analysis are used to peruse the APR behaviour in nitrogen, argon and hydrogen atmospheres. Also for further validation, X-ray diffraction analysis and the scanning electron microscopy were used. The results indicate that APR behaves almost the same in the argon and nitrogen atmospheres. In these conditions, APR decomposes to rhenium oxides during thermal decomposition. However, APR in hydrogen reductive atmosphere is reduced to pure rhenium powder without any reactions. SEM images showed that hydrogen reduced APR had a spherical morphology, but on the other hand the directly reduced rhenium powder in hydrogen atmosphere showed flake morphology.

Understanding molecular, cellular, genetic and functional heterogeneity of tumors at the single-cell level has become a major challenge for cancer research. The microfluidic technique has emerged as an important tool that offers advantages in analyzing single-cells with the capability to integrate time-consuming and labour-intensive experimental procedures such as single-cell capture into a single microdevice at ease and in a high-throughput fashion. Single-cell manipulation and analysis can be implemented within a multi-functional microfluidic device for various applications in cancer research. Here, we present recent advances of microfluidic devices for single-cell analysis pertaining to cancer biology, diagnostics, and therapeutics. We first concisely introduce various microfluidic platforms used for single-cell analysis, followed with different microfluidic techniques for single-cell manipulation. Then, we highlight their various applications in cancer research, with an emphasis on cancer biology, diagnosis, and therapy. Current limitations and prospective trends of microfluidic single-cell analysis are discussed at the end.

Separation of CO 2 from air was simulated in this work. The considered process for removal of CO 2 was a hollow-fiber membrane contactor and an aqueous solution of 2-amino-2-metyl-1-propanol (AMP) as absorbent. The model was developed based on mass transfer as well as chemical reaction for CO 2 and solvent in the contactor. The equations of model were solved using finite element method. Simulation results were compared with experimental data, and good agreement was observed. The results revealed that increasing solvent velocity enhances removal of CO 2 in the hollow-fiber membrane contactor. Moreover, it was found that counter-current process mode is more favorable to achieve the highest separation efficiency.

Circulating levels of branched chain amino acids (BCAAs) correlate strongly with type 2 diabetes (T2D). The correlation may be associated with insulin-resistance factors independent of glycemic markers currently used in the diagnosis and monitoring of diabetes. This can revolutionize the thought process and methodology not only in diabetes treatment, but also in its advance screening and prevention with BCAAs used as biomarkers and targets for treatment. Whether insulin resistance is the cause or result of BCAAs imbalances requires further investigation. Although the overall diet is important, the role of specific diets targeting the gut microbiome composition and hormone secretion affecting BCAA absorption and metabolism will be explored. Generic diet modifications apparently induce only negligible changes in the intrinsic genetic make-up of the gut and BCAA levels but influence specific modulation of the gut microbiome. This genetic make-up is indeed similar among T2D patients independent of numerous variables including obesity. Short-chain fatty acids (SCFAs), the primary end-products of non-digestible carbohydrates (NDC) fermentation, mediate metabolic imbalances through gut microbiota and gut hormone secretion. This review focuses on extensive evidence gathered using diverse methodologies on the strong parallel correlation between BCAA levels and insulin resistance. Furthermore, the role of specific diets particularly SCFAs as mediators of the stubbornly fixed intrinsic genetic make-up of gut microbiota will be scrutinized to delineate BCAA levels and insulin resistance in T2D.