---

Water pollution is one of the most important problems for human beings. BTEX (Benzene, Toluene, Ethylbenzene and Xylenes) have vast application in industry and their carcinogenic effect on human body has approved. Hence these part of water pollutants (water-soluble aromatic components) have more importance. Monitoring systems that can detect presence of BTEX in water supplies are much expensive such as gas chromatography so we need simple systems to reduce the number of samples that we are suspected to them for more analysis by much more expensive systems. Bioreporters are a subgroup of biosensors which are using for sensing and monitoring some signals or reagents. A bioreporter is an organism like a bacteria or a plant that is genetically manipulated to have a promoter which is sensitive to a chemical or physical signal. Activation of the promoter In presense of the signal leads to product of the reporter gene which can be sensed or calculated by our laboratory supplies. A green fluorescent protein gene has been used as a reporter gene downstream of PtbuA1 as a BTEX sensitive promoter in Escherichia coli and its response to BTEX has been investigated in this study. Our results show our bioreporter can sense Toluene.The optimum time and temperature for the bioreporter is also defined.

---

Abstract: In seismic areas, a majority of old RC buildings have only been designed for gravity loads or according to outdated seismic codes. Before1970s, smooth rebars were also extensively used in RC structures. As these buildings are still functioning, they need to be reassessed against seismic demands. Load bearing behaviour of concrete structures reinforced with smooth rebars is considerably affected by the slip deformation of the plain rebars. In this study, a specific finite element model has been proposed for evaluating the seismic performance of these structures. The slipping characteristics of smooth rebars have been incorporated in this model. For this purpose, a tailored stress-strain property has been assigned to the steel fibers in tension. The model has then been calibrated/verified against several sets of experimental results from others. In general, satisfactory correlations have been noticed between the experimental results and the predictions from the proposed fiber element model. The model has also been used for a full seismic assessment of an existing RC building, having smooth rebars. In addition, the structure has been retrofitted with steel bracing, viscose dampers and base isolators' schemes and their nonlinear seismic performance has been evaluated using the proposed model.

---

Aflatoxin B1 is a type of mycotoxin produced by Aspergillus fungi during food production and storage. Aflatoxins have many toxic effects on the body that cause mutagens, teratogens and have high carcinogenic properties that cause cancer in the liver and other organs. Although conventional device methods for measuring aflatoxin B1 in food are sensitive and accurate, they have disadvantages such as high diagnostic time, high cost, the need for a trained user, and the creation of false positive results. Therefore, the development of new measuring methods has been prioritized by researchers. Among these measurement methods is the use of biosensors, which are fast, simple and more affordable and are used in the food industry today. In this work, a colorimetric optical aptasensor using gold nanoparticles with appropriate sensitivity and high selectivity was used to detect aflatoxin B1 in serum and buffer. For this purpose, gold nanoparticles were synthesized by reducing HAuCl₄ by sodium citrate (with a size of 14.40 nm and a zeta potential of -27.5). In this method, the protective effect of DNA sequence on the surface of gold nanoparticles has been used in the presence or absence of aflatoxin with the intervention of salt and the characteristic of visual color change. The detection limit of this method was estimated to be 50 ng/L and its linear range was 200-28000 ng/L. As a result, the designed aptasensor can be used for quick identification and screening of this toxin in contaminated food.
 

---

Aptamers or chemical antibodies are mostly nucleic acid sequences that can bind to various diverse targets including small molecules, large molecules, and cells. Among the advantages of aptamers compared to antibodies, we can mention the in vitro production process, the possibility of choosing aptamers against toxic and non-immunogenic molecules, long-term storage, and much lower production costs. Aptamers can also be easily modified or stabilized, and their synthesis is associated with high purity and reproducibility, they are chemically stable, and due to their  nucleic acid structure, they are much more flexible than antibodies, and they can be used in the form of molecular beacons probes, a combination of use aptamer-target interaction and nucleic acid amplification to achieve highly sensitive detection ranges. These interesting features have made aptamers ideal diagnostic elements for analytical tools such as biosensors, colorimetric methods, surface plasmon resonance, and lab-on-a-chip. However, all these methods require skilled workers and laboratory-based instruments, thus limiting their application. In this regard, lateral flow assay or paper strip kits provide fast and reliable results and only require user intervention in the sample addition phase. Due to their simplicity is widely used in various fields including medicine, food product quality inspection, and environmental safety. In this work, while introducing aptamers, , an overview of its unique application in lateral flow assay and the future of this technology should be studies.
 

---

Gold nanoparticles (GNPs) with unique optical properties, such as easy operation and visualized assay, have a great ability to detect different types of analytes. Today, the use of gold nanoparticles has wide applications in the field of medicine and biotechnology, including the detection of microorganisms that cause contamination in water, air and food and it is considered a suitable alternative for chemical and physical methods. New technologies in the design of biosensors based on GNPs provide the ability to identify biological compounds accurately and quickly. One of these technologies is a detection sensor based on surface plasmon resonance (SPR), which based on its optical properties, is capable of very sensitive and specific measurement of biomolecule interactions without time delay. This technology can quantify in a short time the properties of biomolecular mediators (such as oligonucleotides, proteins and bacteria) on the surface, including reaction speed, tendency and concentration of surface mediators. In this review, while investigating the surface plasmon properties of gold nanoparticles, the simple diagnostic applications of gold nanoparticles based on the localized surface plasmon (LSPR) method and detection in biomedicine.

 

---

New technologies in determining the gender of eggs will greatly help to end the extermination of male chickens, which will save a lot in the poultry industry. These technologies are so valuable and important that many companies and research centers are willing to make large investments to progress in this field. Today, two invasive and non-invasive methods are used to determine the gender of the egg. Invasive diagnostic methods often lead to a decrease in the viability of samples, while non-invasive methods with high accuracy and viability of samples have created a great development capability among researchers. In other words, invasive diagnostic methods determine the gender of the embryos inside the egg with a high percentage, but it can endanger the continuation of the hatching process and jeopardize food safety. However, the use of non-invasive methods in line with industrial use has priority due to the fact that there is no danger to the chick embryo in the process of sex determination. In this review study, while examining the importance of gender determination during hatching for the poultry industry, an attempt has been made to examine and compare all the new technologies used to determine gender in the egg-laying and hatching stages and compare its advantages and disadvantages.

---

 Since 2012, dengue disease has been considered as one of the most important viral diseases transmitted through arthropods and has become one of the major health problems in tropical and subtropical regions of the world In recent years. This virus has four serotypes and is transmitted through the Aedes mosquito. The aim of this Work is to investigate methods for diagnosing, treating, and controlling dengue disease. The method of conducting the study was based on observation and interpretation of information obtained from relevant scientific articles and books. This study was conducted in the spring and summer of 1403 by checking keywords such as Dengue virus, Aedes aegypti, dengue vaccine, detection, protection, chemical control on NCBI, Google, PubMed, WHO search engines. The molecular methods (real-time PCR) and immunoassay are often used to detect dengue virus. In order to prevent the disease, it is also recommended to control the life cycle of Aedes mosquito and use of quadrivalent live and attenuated Dengvxia and TAK-003 vaccines. The clinical treatment of this disease is done using serum therapy and the use of liquids. Finally, chemical and biological control methods of Aedes mosquito are also recommended as strategies to deal with this disease. In this review article, while describing the specific characteristics of dengue virus, the diagnostic and treatment methods of this disease have been scientifically investigated. It is also presented how to prevent control of this disease.

---

In recent decades, experimental studies of the vortex-induced vibration (VIV) became one of the interesting fields of science. However, variety of assumptions and methods of experiments have led to different results in various researches. Several parameters such as mass ratio, aspect ratio, degrees of freedom, and boundary conditions affect the VIV response of a simple circular cylinder. The current paper reports and discusses the results of in-water VIV experiments on an elastically mounted rigid cylinder with various types of end conditions. This paper focusses on the effects of the end condition by attaching an endplate to a circular cylinder and the results compared with those from a cylinder with no endplate. The Reynolds number ranges from 5.8×103 to 6.6×104. Experimental setup have also been compared and verified with some classical results of VIV. Results of current study was favorably compatible with previous researchers’ results.
The experimental results show that, the end condition noticeably changes the VIV amplitude especially in the lock-in area. Moreover, non-dimensional amplitudes shift to the higher reduced velocities when the endplate is removed. In the frequency responses, the cylinder with no endplate has lower quantities rather than the cylinder with an attached endplate. Evaluation of lift force coefficients also shows a similar pattern of effects on the non-dimensional amplitude. Consequently, the excitation of the structure in the lock-in region increases, when the endplate from the cylinder’s end is removed.

---

The current paper deals with the cyclic softening/hardening and strain ratcheting behavior of circular steel tubes under repeated inelastic pure bending. A relatively simple closed-form solution is proposed to tackle the problem. Key physical features involved are the elastic after-effect, accumulated cyclic (creep type) ovalisation of the cross-section, cyclic plasticity including the Bauschinger effect, cyclic softening/hardening of the material and ratcheting effect. The moment-curvature formulation of the tube is derived in an ovalised configuration. Tvergaard stress-strain relation is used to describe the elasto-plastic stress–strain relationship of the material. This continuous nonlinear constitutive model considerably abridges the solution. A combined nonlinear kinematic/nonlinear isotropic hardening rule is used to describe the cyclic uniaxial stress-strain. The analysis of the low cycle pure inelastic bending of the tube is performed under a curvature-control regime. The cycle by cycle growth (creep type) in the ovalization of the cross-section is modeled using a modified version of the Bailey–Norton creep law. The model predictions are examined against a number of available test data on the inelastic monotonic and cyclic bending of tubes and reasonable agreements are observed.