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In the areas of bioimaging and detection, biosensors have attracted extensive attention recently. Specifically, biosensors based on nanostructures provide a more sensitive detection due to their prominent properties. Different biosensors have used quantum dots (QDs) due to their unique properties, like high quantum yield (QY) and photoluminescence. In addition to possessing the advantages of common QDs, carbon quantum dots (CQDs) have a higher solubility, lower toxicity, and easier synthesis, making them highly useful and a promising candidate for biomedical applications. The CQD is a zero-dimensional nanostructure with a size of less than 10 nm in every dimension. The unparallel features of CQDs, including good biocompatibility and unique optical properties, like high photoluminescence (PL) and Quantum yield (QY), make them attractive candidates for biosensor and bioimaging applications. This review examines the recent advances in biosensors based on CQDs and presents the properties, challenges, and future perspectives to pave the way for further studies in the future.

Background: Several typical and atypical findings have been observed in Covid-19 high-resolution computer tomography (HRCT). To our knowledge, there is no study investigating the relationship between the presence of nodules in Covid-19 patients and the patient's condition. Therefore, the present study assessed the frequency of pulmonary nodules in Covid-19 patients according to their condition. Methods: This cross-sectional study assessed the medical images of the patients referred to three university-affiliated centers (Nemazi, Ali Asghar and Shahid Faghihi Hospital) to perform Covid-19 HRCT from April to September 2020. The centers have been named H1, H2, and H3. Patients who were referred to these centers had good, poor, and fair conditions, respectively. The history of patients was assessed carefully. Patients' demographic information, nodule shape, number, size, location, presence of cavitation, and GGO around the nodule were assessed and recorded. Results: Overall, 20576 patients (mean age=46.75±16.64 years old) were included in the study. Only 2.1% of cases had solid nodules. Most of them (96.76%) were accompanied by a GGO (halo sign), and only 10.42% were associated with a cavity. The good condition, patients showed significantly more solid nodules (3.46%) than others. In size of the nodules in good-condition patients (1.8 cm) is significantly larger than in fair-condition (1.22 cm) or poor condition patients (1.15 cm). 79.86%, 12.5%, and 7.64% of nodules were multiple, dual/triple, and single, respectively. Conclusion: The frequency of nodules in the HRCTs of good-condition patients was significantly higher than in fair- or poor-conditionpatients; they also had more multiple and larger-sized nodules. The Pearson-coefficient test also revealed a small negative correlation between the presence of nodules and the patient's condition. It seems the presence of nodules indicates higher immunity to viral infections. In the follow-up, it was revealed that people who had nodules were not hospitalized in the ICU. Further study is needed to prove this point.

Due to the lack of fresh water, production of potable water is one of the important issues for mankind. Capacitive deionization is one of the methods that has recently attracted the attention of researchers due to its simplicity, low price and low energy consumption. The main challenge of this method is high energy consumption at high water concentrations. Therefore, this paper aims to investigate the effect of different effective parameters to improve the system performance. These parameters include feeding voltage, process time, electrode surface area and its capacitance value, overall transfer coefficient, volumetric flow rate and concentration of the feed water, and micropores’ volume, whose effects on energy consumption and number of cycles required to produce potable water are investigated. Results showed that the electrode capacitance and micropores’ volume decreased the necessary process cycles (reducing desalination process time) to produce potable water without significant changes in the energy consumption. The feeding voltage, volumetric flow rate and concentration of the feed water significantly affected the process time and energy consumption. For feed water concentration between 5 and 25 mM, results showed that the minimum values for the desalination process time, electrode surface area, and overall transfer coefficient, are 400 s, 50 cm2 and 0.9 µm/s, respectively. To improve the performance of desalination process in the capacitive deionization cell, development on the physical properties (increasing micropores) and the electrical properties (increasing capacitance value) of the electrodes, as the most important parameters, is suggested.

Cancer is amongst the foremost causes of death worldwide, and the field of nanotechnology presents promising prospects in terms of diagnostic and therapeutic approaches. Theranostics are nanoparticles (NPs) that possess the ability to combine therapeutic and diagnostic capabilities into a single agent. Nonetheless, the synthesis, characterization, and delivery of NPs for theranostics against cancer present obstacles. By providing swift, responsive, and economical platforms for cancer detection and treatment, microfluidic systems based on nanomaterials can overcome these obstacles. A synopsis of recent developments in microfluidic-assisted theranostic nanosystems for the treatment of various malignancies is provided in this mini-review. In addition to microfluidic system-based cancer sensing methods (optical, electrochemical, mechanical, and thermal), efficacious treatment approaches (gene therapy, drug delivery, sonodynamic therapy, etc.) are examined. Further, the potential and limitations of this innovative technique are analyzed, and its potential clinical applications in the future are proposed.

As a major global cause of liver disease, non-alcoholic fatty liver disease (NAFLD) is characterized by excessive hepatocellular accumulation of lipids in the liver, elevated levels of hepatic enzymes, and fibrotic evidence. The primary therapies for NAFLD are changing lifestyle or managing comorbid-associated diseases. Lately, nanotechnology has revolutionized the art of nanostructure synthesis for disease imaging, diagnosis, and treatment. Loading drugs into nanocarriers has been established as a promising strategy to extend their circulating time, particularly in treating NAFLD. In addition, considering a master modulator of adipogenesis and lysosomal biogenesis and function, designing novel nanostructures for biomedical applications requires using biodegradable materials. Various nanostructures, including inorganic nanoparticles (NPs), organic-based NPs, metallic nanocarriers, biodegradable polymeric nanocarriers, polymer-hybrid nanocarriers, and lipid-based nanocarriers have been designed for NAFLD treatment, which significantly affected serum glucose/lipid levels and liver function indices. NPs modified with polymers, bimetallic NPs, and superparamagnetic NPs have been used to design sensitive nanosensors to measure NAFLD-related biomarkers. However, certain limitations are associated with their use as diagnostic agents. The purpose of this review article is to shed light on the recent advancements in the field of nanomedicine for the early diagnosis, treatment, and prognosis of this progressive liver disease.

Cancer is one of the most life-threatening family of diseases that cause death worldwide. As a highly researched and successful therapeutic agent, methotrexate (MTX) treats many solid tumours, hematologic malignancies, and autoimmune illnesses. Despite many benefits, methotrexate induces drug resistance and limits plasma half-life due to its poor pharmacokinetics. The variable biological availability have prompted researchers to investigate innovative delivery strategies for enhancing its therapeutic qualities. To develop more suitable methotrexate formulations, nanoparticles (NPs) have recently gained a significant interest. A wide range of nanoparticles, including polymer-based nanoparticles, carbon-based nanoparticles, lipid-based nanoparticles, as well as inorganic nanoparticles, can be deliver cancer chemotherapeutics such as methotrexate. Loading methotrexate into NPs can provide a delivery system that has shown great promise to carcinoma therapy. In this review, we will describe the feasibility of NP-based strategies to deliver methotrexate in cancer therapy, outlining the current state of the art and the challenges/promises for the future.

Despite many advances in the diagnosis, screening, and rapid treatment of tuberculosis, it is still a public health concern in the world. Due to the importance of this issue in diagnosis and reduction of transmission of infection and treatment of the disease especially where this study was conducted due to the high prevalence of tuberculosis, the aim of our study was to determine the relationship between sputum smear positivity grade and chest X-ray findings in pulmonary tuberculosis patients in a hospital in southeast of Iran. This cross-sectional study was performed on all patients with pulmonary TB referencing the health centers in the Zabol city from January 1, 2015 to December 30, 2020. Sputum smear and radiographic findings of the chest X-ray were evaluated. Data was collected using a form of information and finally analyzed by SPSS 22. Out of 101 patients examined in the present study, 71 were women and 30 were men. The mean age of the patients was 62.6813.61 years. The frequency of opacity in patients with grades 1, 2, and 3 was 71.4, 78.5, and 76.5%, respectively. Frequency of cavitation in patients with grade 1, 2 and 3 was 11.5%, 28.5% and 52.9% respectively (P value 0.001). The frequency of reticulonodular presentations in patients with grade 1, 2, and 3 was 24.2, 7.1, and 0%, respectively. In general, the results of this study showed that, with increasing grading of smears (1+, 2+, and 3+), the frequency of cavitation presentation increased significantly and the frequency of reticulonodular presentations decreased significantly. The findings of the present study can help physicians to improve TB diagnostics.

Diabetes is one of the most common non-contagious diseases in the world. This disease is the fourth or fifth cause of death in most developed countries. The relationship between tuberculosis and diabetes had been introduced years ago and diabetes is considered a threatening factor in tuberculosis in the research history. Not only tuberculosis is prevalent among diabetic persons, but also diabetes can affect the appearance of imaging of tuberculosis. This is a kind of analytic study, a case-control study, which was carried out between the years 2014 and 2015 in Zabol City. In this study, the radiographic findings from the patients suffering from pulmonary tuberculosis in diabetic patients and not diabetic patients are compared. These radiographic were handed to a radiologist and the radiologic findings of these graphs from the anatomic location (upper and lower half of the right and left bellows), Presence or absence of cavities, nodules, density and pleural involvement were recorded and compared with the diabetic and non-diabetic group. After gathering of the data using SPSS software, descriptive statistics were presented in the form of (frequency, percent) graphs and a chi-square test (p

Harvesting energy from environmental motions is an efficient method to prepare permanent power supplies for intelligent wireless systems. In this paper, a single spiral electrode triboelectric nanogenerator (TENG) is fabricated and investigated for energy harvesting from multi-directional sliding motions. The device is intended to be also used as a self-powered dynamic velocity sensor. In the first step, four samples are fabricated and characterized by applying 2 Hz sliding motions. The results show an increase in the output power from 1.53 to 20.72 nW, for a device with 4 to 20 turns. To compare the results, the effect of increasing the output power using a parallel array is also studied. In the next step, applications of the device as velocity and position sensors are investigated. A linear dependence between the input and output of the sensor is noticed for the device with 8, and 16 spiral turns. Finally, a circuit modeling for the device is presented, and a trend is suggested for the virtual capacitive behavior of the single electrode TENG.

Triboelectric nanogenerator is a promising technology and emerging approach for harvesting environmental mechanical energy. However, because of nature of the environmental mechanical motions, the amplitude and direction of the movements are unpredictable. In this paper, a triboelectric nanogenerator with a zero inductance spiral electrode is proposed to generate electricity from sliding motions, regardless of the motion direction. Various samples with different electrode size and number of spiral electrodes were fabricated and characterized. To obtain the optimum output power density, response surface methodology was employed. The experiments were designed based on the central composite design approach for different combinations of the electrode turn number and the electrode width and pitch. To show the validity and accuracy of the method, the predicted results were compared with additional experimental results which a good concordance between the results. Contours of output power density for different combinations of the design variables were plotted. The latter helps designers to easily find the optimal configuration to obtain the desired power output.

Introduction The placenta is considered to be the most vital organ of the infant. The intrauterine fetal growth and development indicates a harmony between the fetus, placenta, and mother. Studies show that placenta has different effects on maternal and neonatal outcomes. This study aimed to investigate the effect of placenta location on placental weight (PW) and infant birth weight (IBW) in pregnant mothers. Material and Methods This descriptive study was performed on 370 pregnant mothers and their newborns referring to Amir-al- Momenin Hospital in Zabol, south of Iran from October to March 2018. The data collection tool included a researcher-made checklist consisting of two parts: maternal demographic information and infant information. The placenta location was determined by ultrasound and recorded by a radiologist and the Apgar’s score was measured by an obstetrician in the delivery room. The collected data were then analyzed using descriptive and analytical tests. Results The mean± SD of maternal age, maternal BMI, Apgar score, and IBW was 30.39±5.44. 25.24 ± 4.54, 9.65 ± 0.65, 3244.61 ± 204.116 gr, and 548.83± 104.65 gr, re- spectively. Most of the infants were male (50.3%). The placenta was mainly located in the fundal portion of the womb (44.9%). Results showed no significant relation- ship between the placental location and IBW (p = 0.555). However, the results showed a significant relationship between the placental location and PW (p = 0.028). Conclusion Since the results of this study indicate the relationship be- tween placental location and PW and infants' gender, spe- cialists are recommended to consider placental location as a factor affecting PW.

Introduction Magnesium sulfate has many side effects on the fetus and pregnant mother. On the other hand, considering different blood supply rates to the anterior and posterior regions of the uterus, we decided to conduct this study to investigate the relationship between placental location and neonatal magnesium levels in mothers with preeclampsia. Materials and methods This descriptive study was performed on 74 pregnant women and their newborns referring to Amir-al- Momenin Hospital in Zabol city, south of Iran from 1 February, 10 2019 to Aguest, 10 2019. The data collec- tion tool was a researcher-made checklist consisting of two parts: Information about maternal and neonatal de- mographic characteristics. Blood samples were taken from neonatal cord and the magnesium level was meas- ured Results The mean ± SD of mother’s age in the case and control groups was 24.62 ± 1.14 and 22.97 ± 1.14 years, respec- tively. Neonatal blood magnesium level in case and con- trol groups was 2.58 ± 0.339 and 1.87 ± 0.37, respectively. Statistical analysis showed a significant dif- ference between the two groups only regarding neonatal weight and blood magnesium level (p = 0.001). The re- sults also showed no relationship between placental loca- tion and neonatal magnesium level (p = 0.698). Conclusion The results of the present study indicate no relationship between the placental location and neonatal blood mag- nesium level, and it is thus recommended to carry out fur- ther studies with larger sample size to investigate such more accurately.

Freshwater resources are limited; thus, different technologies for desalination of brackish and seawater have been developed. Capacitive deionization (CDI) is one of the most promising desalination technologies owing to its low cost, simplicity, nonmoving parts, and low energy consumption. However, its energy consumption significantly increases with desalination of high-salinity water. In this regard, a good understanding of the effects of different process parameters on CDI energy consumption is crucial for further performance improvement. Therefore, the surface response methodology (RSM) was adopted to systematically study the effects of applying voltage, Stern layer capacity, volume and concentration of feed water, and volume of micropores on energy consumption and desalination time. The results showed that the Stern layer capacity and volume of micropores reduced desalination time by approximately 25% without significant changes in energy consumption. With the design of an improved electrode (improving the micropore structure for ion adsorption), the desalination time (Cycle) was reduced and a slight reduction in energy consumption was achieved. It can be claimed that any improvement in the physical (porosity) and electrical properties of the electrodes, results in an important increase in the performance of the CDI system. [ABSTRACT FROM AUTHOR]

PVDF is one of the most widely used dielectric polymers that has four phases. Among them, only its β phase shows piezoelectric property, which is accessible through an electrospinning synthesis method. In this research, a solution of dimethylformamide (DMF) and tetrahydrofuran (THF), with different ratios, and two different polymer concentrations, as well as various ZnO percentages, were used for synthesis of PVDF/NP-ZnO nanofibers composite. The samples that led to the formation of nanofibers were characterized. The results indicate that nanofibers were appropriately formed at lower concentrations of polymer and zinc oxide with equal ratio of the two solvents. To study the effects of synthesis conditions on the morphology and diameter of the nanofibers, the samples were synthesized at different intervals and at different injection rates. The results show that at lower intervals, the injection rate should be reduced to form more uniform nanofibers without nodes and sprays. Finally, flexible piezoelectric nanogenerators were fabricated based on the best samples and were tested under vibrational mechanical forces. The results indicate a maximum output power of 32 nW/cm2. The greater output current and voltage were resulted by using more uniform and stretched nanofibers. Keywords: Nanofibers, PVDF, ZnO, Electrospinning, Nanogenerator