Miracle-dz/UniFAR-FTUs huggingface dataset:
Synthesis, characterization, and molecular docking analysis of Chitosan-gr-Polysulphanilic acid as antimicrobial water-soluble polymers

Abstract As a hydrophilic polysaccharide derived from chitin, chitosan has a broad antibacterial spectrum against bacteria and fungi. Activity depends on polymer molecular weight (MW) and degree of acetylation (DA). The activity of polysulphanilic acid as an antimicrobial is very poor. Chitosan graft polysulphanilic acid was synthesized and characterized by some instrumental tools, such as UV-visible, IR spectroscopy, SEM, XRD, and TGA. The obtained graft was introduced to use as an antimicrobial. The obtained data reveals a good antimicrobial activity for different types of the organism as Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. For the effect of chitosan, three antibacterial mechanisms are proposed. The ionic surface interaction results in wall cell leakage the inhibition of the mRNA and protein synthesis via the penetration of chitosan into the nuclei of the microorganisms; and the formation of an external barrier, chelating metals, and provoking the suppression of essential nutrients to microbial growth. It is likely that all events occur simultaneously but at different intensities. Chitosan–graft–polysulphanilic acid as a water-soluble polymeric material gives higher efficiency than chitosan and the used references for both gram-positive and gram-negative bacteria. Also, The molecular docking analysis showed that Chitosan-gr-Polysulphanilic acid interacts with the five receptors via different types of interactions, such as hydrogen bonding, van der Waals, and pi-interactions with high binding energies. Also, Chitosan–graft–poly sulphanilic acid has better ADMET and physicochemical properties. So, Chitosan–graft–poly sulphanilic acid can be used as an antimicrobial agent. GRAPHICAL ABSTRACT
Green Synthesis and Characterization of Titanium Nanoparticles Using Microalga, Phaeodactylum tricornutum

Abstract Nanoparticles synthesized from microalgae offer a newly discovered process that is open to improvement. In this study supernatant of Phaeodactylum tricornutum (P. tricornutum) culture was used for this purpose. Firstly, the effects of some variables, namely titanium concentrations, titanium:supernatant ratio, pH, incubation time, and mixing speed on nanoparticle synthesis were investigated by using statistical design method in shaken culture as well as bioreactor. The average nanoparticle size synthesized in optimum conditions which were pH 7.5 with 300 rpm for 1 h was found as 50 nm. In the second part, nanoparticles were coated with a chitosan solution to protect their stability and increase their potential. Therefore, the antimicrobial activity showed a reasonable effect on these nanoparticles coated with chitosan. Nanoparticles produced had interestingly shown 99% antistatic properties. According to the cytotoxicity test, these nanoparticles showed a high cytotoxic effect on different cancer cell lines. The results obtained in the present study can be considered promising outcomes for possible future antimicrobial, biogenic and antistatic studies particularly in biomedical applications.
Effects of tropical rainforest conversion to rubber plantation on soil quality in Hainan Island, China

Abstract. Land-use changes can alter soil properties and thus affect soil quality. Our understanding of how forest conversion (from tropical rainforest to rubber plantations) affects soil properties and soil quality is limited. An ideal testing ground for analyzing such land-use change and its impacts is Hainan Island, the largest tropical island in China. Based on 21 soil physicochemical and biological properties, a soil quality index (SQI) employed principal component analysis to assess soil quality changes from the conversion of tropical rainforests to rubber plantations. The results showed that (i) soil available potassium, available phosphorus, microbial biomass carbon, cellulose decomposition, acid phosphatase, and urease were vital soil properties for soil quality assessment on Hainan Island. (ii) The SQI of rubber plantations decreased by 26.48 % compared to tropical rainforests, while four investigated soil properties (soil pH, total phosphorus, cellulose decomposition, and actinomyces) increased. (iii) The SQI of both the tropical rainforests and rubber plantations showed significant spatial differences, which, under tropical rainforests, was more sensitive to seasonal changes than those under rubber plantations. (iv) Structural equation modeling suggested that forest conversion directly impacted soil quality and, indirectly impacted soil qualities' spatial variation by their interaction with soil types and geographical positions. Overall, though the conversion of tropical rainforest to rubber plantation did not decrease all soil properties, the tropical rainforest with its high soil quality should be protected.
Safety Risks of Plant Fiber/Plastic Composites (PPCs) Intended for Food Contact: A Review of Potential Hazards and Risk Management Measures

Plant fiber/plastic composites (PPCs), with the benefits of low cost and easy processing, have been widely used in the production of various food contact products. They are generally considered to be economical and environmentally friendly because of their natural raw materials (plant fibers) and recommended to be one of the ideal alternatives to traditional petrochemical-based plastics. However, in addition to plastic resins and plant fibers, some indispensable additives are involved in the production process of PPCs, which may pose food safety risks. To date, excessive migration of hazardous substances (such as melamine) has been reported in some products made of PPCs, and the safety and applicability of PPCs as food contact materials need to be further studied. In this paper, the main raw materials of PPCs used for food contact are taken as the pointcut to analyze the possible hazards, sources of hazards, and existing risk management measures in various countries. The conclusion shows that PPCs used for food contact may have potential safety risks at present. However, systematic research on migration methods and safety assessment are still insufficient, and further studies are needed regarding the main safety risks and migration patterns.
Developing an Orienteering Attitudes Scale: A Validity and Reliability Study

Orienteering is an increasingly popular sport activity. Because orienteering is believed to improve cognitive, affective, and behavioural skills, it is used in many classes such as social studies, geography, and physical education. It is, thus, of critical importance to know attitudes towards orienteering, especially among middle school students to use orienteering more effectively and efficiently. This study aimed to develop a reliable and valid scale to measure middle school students’ attitudes towards orienteering. To this end, the study sampled 600 students who were attending fifth, sixth, seventh, and eighth grades during the fall term of the 2019-2020 academic year. Expert opinion was sought for the content and face validity of the scale. The results of the exploratory factor analysis (EFA) conducted for the construct validity indicated a three-factor structure consisting of sixteen items, which accounted for 65.06% of the total variance. The factor loadings of the scale items ranged from 0.61 and 0.94. According to the results of the confirmatory factor analysis (CFA), the goodness of fit indices (GFI) were as follows: χ2/df = 2.37, RMSEA = 0.07, GFI = 0.91, AGFI = 0.88, SRMR = 0.05, RFI = 0.95, CFI =0.97, IFI = 0.97, NFI = 0.96, and NNFI = 0.97. The reliability of the scale was tested using the Cronbach’s alpha coefficient, the test-retest reliability coefficient, the significance of the correlation coefficients for the scale and subscales, and the upper and lower 27%. The Cronbach’s alpha coefficient was found to be . 92 for the total scale, . 89 for the affective subscale, . 89 for the behavioural subscale, and . 72 for the cognitive subscale. Based on the findings, the Orienteering Attitudes Scale is a valid and reliable measure and can be used to measure middle school students’ attitudes towards orienteering.
Impact of buildings on the performance of MEO satellite mobile communication systems for low bit rate applications

Mobile communications for low bit rate applications via midearth orbit (MEO) satellites are considered. Owing to multipath interference, fading of the received signal appears in low bit rate applications. The received signal levels, at the mobile in the presence of buildings, are calculated using the uniform theory of diffraction (UTD) for horizontal and vertical polarisations. Buildings are considered in both residential and moderate urban environments. For easy reference, explicit mathematical representations with illustrations of all significant ray contributions are given. Furthermore, the signal levels data, extracted from the electromagnetics computations, are used to evaluate communication system performance in terms of bit error rate and depolarisation of the received signal. Moreover, computed results are in agreement with actual measured data.
Endoscopic submucosal dissection for rectal neoplastic lesions: experience from a European center.

Nowadays, various endoscopic resections including polypectomy, endoscopic mucosal resection (EMR), and endoscopic submucosal dissection (ESD) are well known first-line approaches for early neoplastic rectal tumors.In this case series study, we analyzed 320 ESD procedures performed in a high-volume colorectal center in Poland, Europe. The aim of this study was to retrospectively evaluate ESD procedure in cases of rectal carcinoma performed by a single trained operator in a referral center provided with endoscopy.Overall, en bloc resection was observed in 92.5% of patients (296/320). The en bloc resection rate was at a similar level in those lesions with involved anal sphincters versus tumors without involvement (93.85% vs. 92.16%; p=0.644). R0 resection was noted in 89.4% of patients (286/320). The overall curative ESD rate was 85.94% (n=275). The curative ESD rate in the invasive cancer group reached 52.6% (n=20). We observed ESD-related adverse events, such as bleeding and perforation, in 3.4 % of patients (n=11). We have demonstrated that ESD in rectal tumors is an efficient and safe procedure with a high curative rate, even in difficult lesions. Anal sphincter localization and recurrent character of the lesion have no impact on the final outcomes. The ESD approach should have been considered for all rectal tumors, especially those lesions suspected of superficial mucosal invasion, as it can serve as a staging method and may have been curative for adenomas and cancers limited to mucosa.
Cool Roofs and Thermal Insulation: Energy Savings and Peak Demand Reduction

Cool roofs are defined by the Cool Roof Rating Council as a product with solar reflectivity of at least 0.70 and infrared emissivity of at least 0.75. In its 2005 revision, Title 24, California Energy Efficiency Standards for Residential and Nonresidential Buildings, cool roofs are prescribed in the standard non-residential building. While cool roofs decrease the solar gain of buildings, thus lowering cooling energy demand, additional insulation also does it. This work investigates the levels of insulation required with a black roof to accomplish the same cooling energy demand that cool roofs have with minimum insulation requirements. Both total and peak energy demands are considered and the levels of insulation to accomplish them are different. Oak Ridge National Laboratory’s Simplified Transient Analysis of Roofs (STAR) computer code was used to predict the transient heat gain and structure temperatures. The 16 Climate Zones in California were used, as well as the minimum insulation requirements dictated by 2005 Title 24 legislation. The results were compared with the results predicted by the overall envelope approach of the legislation.
An overview of decentralized Kalman filter techniques

The federated Kalman filter, which combines data from multiple Kalman filters, is discussed. The federated filter can provide performance equal to that of a single Kalman filter that integrates all the independent sensor data in the system. The advantage is that a single filter is impractical with existing sensors. The federated filter is practical, but for true optimal performance it is necessary that all Kalman filters contain the same process model and make their covariance matrices available on the serial data bus. The federated filter can be reconfigured to provide a less optimal solution with a higher degree of fault tolerance. The application of the federated filter to combine data from two Kalman filters in a navigation system is simulated, and results are provided. <<ETX>>
Improved empirical model for the Jerusalem cross

The frequency transmission characteristics of Jerusalem cross grids at oblique angles of incidence are investigated experimentally, and an improved equivalent circuit model for the cross is proposed. Particular attention is given to the properties of the upper resonant frequency band and its application to dichroic reflector antennas. This upper resonance is essentially dipole in nature, changing in frequency as the angle of incidence is varied. It occurs at a higher frequency than expected and is influenced not only by the length of the end caps but also by the mutual reactance between the end caps and the main arm of the cross. An equivalent circuit model for the cross is presented, which more closely matches the observed responses than previous models. Experimental results for a complementary Jerusalem cross grid are also discussed.
Sustainable Development of Employability of University Students Based on Participation in the Internship Promotion Programme of Zhejiang Province

In the context of severely restricted employment opportunities, undertaking an internship is an important way for students to enhance their employability and sustainable development. The aim of this study was to judge if the implementation of the Internship Promotion Programme (IPP) at universities in Zhejiang Province, China, could enhance graduates’ employability. We conducted surveys and interviews with 400 students and 100 business executives who participated in the IPP during the past 6 years. Based on the collected data and statistical analysis, the findings show that internships help students to improve their innovative thinking, interpersonal communication abilities (domestic and international), problem-solving skills, value creation and responsibility. Participants in the IPP were compared with students who did not take part. The results demonstrated that the IPP participants exhibited higher capabilities to perform important workplace tasks and that as a result, they became more attractive to employers. The analysis, therefore, demonstrates a positive correlation between the internship experience and employability. As a result, it can be concluded that the IPP improves students’ employability and is beneficial to enhancing the quality of higher education, and hence the sustainable development of students.
On the design workflow of auxetic metamaterials for structural applications

Auxetic metamaterials exhibit an unexpected behaviour of a negative Poisson’s ratio (NPR), meaning they expand transversely when stretched longitudinally. This behaviour is generated predominantly due to the way individual elements of an auxetic lattice are structured. These structures are gaining interest in a wide variety of applications such as energy absorption, sensors, smart filters, vibration isolation and medical etc. Their potential could be further exploited by the use of additive manufacturing. Currently there is a lack of guidance on how to design these structures. This paper highlights state-of-the-art in auxetic metamaterials and its commonly used unit-cell types. It further explores the design approaches used in the literature on creating auxetic lattices for different applications and proposes, for the first time, a workflow comprising design, simulation and testing of auxetic structures. This workflow provides guidance on the design process for using auxetic metamaterials in structural applications.
Hypervelocity projectile design and fabrication

The authors present the design and fabrication techniques that have been used to increase the strength of the projectiles used in the STARFIRE Project. In addition, various diagnostics that have been used to guide the projectile development and monitor projectile integrity are reviewed. Stronger projectile designs have been fabricated with a concurrent reduction in precision machining time. The improvements in projectile strength have allowed increases in reliable projectile injection velocities from 6 km/s to 7 km/s. In addition, the molded projectile fabrication technique offers additional flexibility for the fabrication of complex projectile designs. One of these advanced projectile concepts which uses a base sealing design offers the potential for further increases in injection velocity. >
Sensorless drive of surface-mounted permanent-magnet motor by high-frequency signal injection based on magnetic saliency

This paper presents a new sensorless control scheme of a surface-mounted permanent-magnet (SMPM) motor using high-frequency voltage signal injection method based on the high-frequency impedance difference. In the SMPM motor, due to the flux of the permanent magnet, the stator core around the q-axis winding is saturated. This makes the magnetic saliency in the motor. This magnetic saliency has the information about the rotor position. The high-frequency voltage signal is injected into the motor in order to detect the magnetic saliency and estimate the rotor position. In this paper, the relationship between the high-frequency voltages and high-frequency currents is developed using the voltage equations at the high frequency, and the high-frequency impedance characteristics are analyzed experimentally under various conditions. The proposed sensorless control scheme makes it possible to drive the SMPM motor in the low-speed region including zero speed, even under heavy load conditions. The experimental results verify the performance of the proposed sensorless algorithm.
Avalanche multiplication noise characteristics in thin GaAs p/sup +/-i-n/sup +/ diodes

Avalanche noise measurements have been performed on a range of homojunction GaAs p/sup +/-i-n/sup +/ and n/sup +/-i-p/sup +/ diodes with "i" region widths, /spl omega/ from 2.61 to 0.05 /spl mu/m. The results show that for /spl omega//spl les/1 /spl mu/m the dependence of excess noise factor F on multiplication does not follow the well-established continuous noise theory of McIntyre [1966]. Instead, a decreasing noise factor is observed as /spl omega/ decreases for a constant multiplication. This reduction in F occurs for both electron and hole initiated multiplication in the thinner /spl omega/ structures even though the ionization coefficient ratio is close to unity. The dead-space, the minimum distance a carrier must travel to gain the ionization threshold energy, becomes increasingly important in these thinner structures and largely accounts for the reduction in noise.
Do comprehensive deep learning algorithms suffer from hidden stratification? A retrospective study on pneumothorax detection in chest radiography

Objectives To evaluate the ability of a commercially available comprehensive chest radiography deep convolutional neural network (DCNN) to detect simple and tension pneumothorax, as stratified by the following subgroups: the presence of an intercostal drain; rib, clavicular, scapular or humeral fractures or rib resections; subcutaneous emphysema and erect versus non-erect positioning. The hypothesis was that performance would not differ significantly in each of these subgroups when compared with the overall test dataset. Design A retrospective case–control study was undertaken. Setting Community radiology clinics and hospitals in Australia and the USA. Participants A test dataset of 2557 chest radiography studies was ground-truthed by three subspecialty thoracic radiologists for the presence of simple or tension pneumothorax as well as each subgroup other than positioning. Radiograph positioning was derived from radiographer annotations on the images. Outcome measures DCNN performance for detecting simple and tension pneumothorax was evaluated over the entire test set, as well as within each subgroup, using the area under the receiver operating characteristic curve (AUC). A difference in AUC of more than 0.05 was considered clinically significant. Results When compared with the overall test set, performance of the DCNN for detecting simple and tension pneumothorax was statistically non-inferior in all subgroups. The DCNN had an AUC of 0.981 (0.976–0.986) for detecting simple pneumothorax and 0.997 (0.995–0.999) for detecting tension pneumothorax. Conclusions Hidden stratification has significant implications for potential failures of deep learning when applied in clinical practice. This study demonstrated that a comprehensively trained DCNN can be resilient to hidden stratification in several clinically meaningful subgroups in detecting pneumothorax.
GROWTH OF MULTI-WALLED CARBON NANOTUBES ALONG WITH GRAVITY BY SPRAY PYROLYSIS OF NATURAL PRECURSOR

Carbon nanotubes are prepared along the gravity direction in a spray pyrolysis setup over the silica-supported FeCo-Ni catalyst. The silica-supported Fe-Co-Ni catalyst coated over the copper strip is inserted in such a way the coating surface faces downward so that carbon nanotubes can grow along the direction of gravity. Plant-based natural precursor, Pine oil, is used as a carbon source for the preparation of carbon nanotubes by spray pyrolysis method. The effect of precursor flow rate on yield, morphology and structural properties of carbon nanotubes prepared along gravity are discussed. At an optimum flow rate, carbon nanotubes are formed in good yield. The carbon nanotubes synthesized are characterized using appropriate techniques. The scanning electron microscope results show that the synthesized carbon nanotubes are long, straight and well graphitized multi-walled type. The carbon nanotubes diameters are around 50 nm and the average length 20μm. Raman spectroscopy studies revealed that carbon nanotubes are well graphitized multi-walled type with defect-free. A mechanism for the growth of carbon nanotubes along gravity is proposed. Spray pyrolysis of the natural precursor, Pine oil, along with gravity over inversely placed support catalyst material is a promising technique for the growth of long and narrow carbon
Simulation and Analysis of Grid Formation Method for UAV Clusters Based on the 3 × 3 Magic Square and the Chain Rules of Visual Reference

Large-scale unmanned aerial vehicle (UAV) formations are vulnerable to disintegration under electromagnetic interference and fire attacks. To address this issue, this work proposed a distributed formation method of UAVs based on the 3 × 3 magic square and the chain rules of visual reference. Enlightened by the biomimetic idea of the plane formation of starling flocks, this method adopts the technical means of airborne vision and a cooperative target. The topological structure of the formation’s visual reference network showed high static stability under the measurement of the network connectivity index. In addition, the dynamic self-healing ability of this network was analyzed. Finally, a simulation of a battlefield using matlab showed that, when the loss of UAVs reaches 85% for formations with different scales, the UAVs breaking formation account for 5.1–6% of the total in the corresponding scale, and those keeping formation account for 54.4–65.7% of the total undestroyed fleets. The formation method designed in this paper can maintain the maximum number of UAVs in formation on the battlefield.