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1.
Sensors (Basel) ; 22(13)2022 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-35808492

RESUMEN

In 2019, Wen et al. proposed authenticated semi-quantum key distribution (ASQKD) for identity and message using the teleportation of W states and GHZ-like states without pre-shared keys. However, the ASQKD protocol presents a vital issue in the teleportation of W states owing to its inappropriate design. Bob recovers the teleported W states without obtaining the position of the corresponding photons and then returns the recovered photons back to Alice. Hence, the teleportation of W states in Wen et al.'s ASQKD protocol was malfunctioning. Moreover, Wen et al.'s ASQKD protocol requires quantum memory, which strongly disobeys the definition of semi-quantum proposed by Boyer et al. Therefore, in this study, we discover the flaws of Wen et al.'s ASQKD protocol and propose an authenticated semi-quantum key distribution protocol. When compared to Wen et al.'s ASQKD protocol, the proposed ASQKD protocol has the following advantages: legal semi-quantum environment (i.e., does not require quantum memory), reduced quantum hardware requirement (i.e., based only on W states), does not involve classical cryptography (i.e., the hash function), and provided 1.6 times higher qubit efficiency.


Asunto(s)
Computadores
2.
Entropy (Basel) ; 24(10)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37420428

RESUMEN

Recently, Zhao et al. proposed a semi-quantum bi-signature (SQBS) scheme based on W states with two quantum signers and just one classical verifier. In this study, we highlight three security issues with Zhao et al.'s SQBS scheme. In Zhao et al.'s SQBS protocol, an insider attacker can perform an impersonation attack in the verification phase and an impersonation attack in the signature phase to capture the private key. In addition, an eavesdropper can perform a man-in-the-middle attack to obtain all of the signer's secret information. All of the above three attacks can pass the eavesdropping check. Without considering these security issues, the SQBS protocol could fail to ensure the signer's secret information.

3.
Rapid Commun Mass Spectrom ; 32(7): 552-560, 2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29380926

RESUMEN

RATIONALE: Paper spray ionization (PSI) is an attractive ambient ionization source for mass spectrometry (MS) since it allows the combination of surface sampling and ionization. The minimal sample preparation inherent in this approach greatly reduces the time needed for analysis. However, the ions generated from interfering compounds in the sample and the paper substrate may interfere with the analyte ions. Therefore, the integration of PSI with high-field asymmetric ion mobility spectrometry (FAIMS) is of significant interest since it should reduce the background ions entering the mass analyzer without complicating the analysis or increasing analysis time. Here we demonstrate the integration of PSI with FAIMS/MS and its potential for analysis of samples of forensic interest. METHODS: In this work, the parameters that can influence the integration, including sampling and ionization by paper spray, the FAIMS separation of analytes from each other and background interferences, and the length of time that a usable signal can be observed for explosives on paper, were evaluated with the integrated system. RESULTS: In the negative ion analysis of 2,4,6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), amounts as low as 1 ng on paper were readily observed. The successful positive ion separation of a set of illicit drugs including heroin, methamphetamine, and cocaine was also achieved. In addition, the positive ion analysis of the chemical warfare agent simulants dimethyl methylphosphonate (DMMP) and diisopropyl methylphosphonate (DIMP) was evaluated. CONCLUSIONS: The integration of PSI-FAIMS/MS was demonstrated for the analyses of explosives in negative ion mode and for illicit drugs and CW simulants in positive mode. Paper background ions that could interfere with these analyses were separated by FAIMS. The compensation voltage of an ion obtained by FAIMS provided an additional identification parameter to be combined with the mass spectrum for each analyte.


Asunto(s)
Ciencias Forenses/métodos , Espectrometría de Movilidad Iónica/métodos , Espectrometría de Masas/métodos , Sustancias para la Guerra Química/análisis , Sustancias para la Guerra Química/química , Sustancias Explosivas/análisis , Sustancias Explosivas/química , Drogas Ilícitas/análisis , Drogas Ilícitas/química , Papel , Tetranitrato de Pentaeritritol/análisis , Trinitrotolueno/análisis
4.
Rapid Commun Mass Spectrom ; 31(19): 1565-1572, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28681982

RESUMEN

RATIONALE: A desired feature in the analysis of explosives is to decrease the time of the entire analysis procedure, including sampling. A recently utilized ambient ionization technique, paper spray ionization (PSI), provides the possibility of combining sampling and ionization. However, an interesting phenomenon that occurs in generating negatively charged ions pose some challenges in applying PSI to explosives analysis. The goal of this work is to investigate the possible solutions for generating explosives ions in negative mode PSI. METHODS: The analysis of 2,4,6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) was performed. Several solvent systems with different surface tensions and additives were compared to determine their effect on the ionization of explosives. The solvents tested include tert-butanol, isopropanol, methanol, and acetonitrile. The additives tested were carbon tetrachloride and ammonium nitrate. RESULTS: Of the solvents tested, isopropanol yielded the best results. In addition, adding ammonium nitrate to the isopropanol enhanced the analyte signal. Experimentally determined limits of detection (LODs) as low as 0.06 ng for PETN, on paper, were observed with isopropanol and the addition of 0.4 mM ammonium nitrate as the spray solution. In addition, the explosive components of two plastic explosive samples, Composition 4 and Semtex, were successfully analyzed via surface sampling when using the developed method. CONCLUSIONS: The analysis of explosives using PSI-MS in negative ion mode was achieved. The addition of ammonium nitrate to isopropanol, in general, enhanced the analyte signal and yielded better ionization stability. Real-world explosive samples were analyzed, which demonstrates one of the potential applications of PSI-MS analysis.

5.
Anal Chem ; 88(19): 9435-9442, 2016 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-27573799

RESUMEN

Ammonium nitrate (AN) and urea nitrate (UN) are commonly used materials in improvised explosive devices (IEDs). Detection by mass spectrometry (MS) and/or ion mobility spectrometry (IMS) is traditionally difficult. The major challenges of detecting these species arise from their ionic nature and their low mass (for MS detection) and size (for IMS detection). Although AN and UN both produce characteristic higher mass (and size) cluster ions when ionized by electrospray ionization (ESI), detection of AN/UN using cluster ions poses difficulty at trace levels because their formation is concentration-dependent. The addition of modifiers to the ESI process is demonstrated here to overcome some of these challenges for the detection of AN and UN using MS and/or IMS.

6.
Front Psychol ; 13: 868698, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35769741

RESUMEN

Given the current popularization of computer programming and the trends of informatization and digitization, colleges have actively responded by making programming lessons compulsory for students of all disciplines. However, students from different ethnic groups often have different learning responses to such lessons due to their respective cultural backgrounds, the environment in which they grew up, and their consideration for future employment. In this study, an AI-assisted programming module was developed and used to compare the differences between multi-ethnic college students in terms of their theoretical and actual learning expectancy, motivation, and effectiveness. The module conducted analysis through the deep learning network and examined the relevant processes that the students underwent during programming lessons, as well as the types of errors they had committed. Their learning motivation for and actual learning performance in programming were then examined based on the cognitive learning theory. The results of the experiment, which involved 96 multi-ethnic college students, indicated that the two groups had dissimilar theoretical performance in terms of their expectancy and motivation for learning programming. The indigenous students' main concern was whether programming would affect their families or tribes, and this concern affected and was reflected in their learning outcomes. In contrast, the learning motivation and goals of Han Chinese students were driven by the cognition of the value of programming to themselves. The research findings can contribute toward the cognition and understanding of multi-ethnic students when learning computer programming and development of the appropriate teaching methods, and serve as a reference for subsequent research on integrating multiculturalism into computer programming lessons.

7.
Anal Chem ; 83(24): 9237-43, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22017325

RESUMEN

High-field asymmetric waveform ion mobility spectrometry (FAIMS) separates ions by utilizing the mobility differences of ions at high and low fields. The shape of the waveform is one of the essential features affecting the resolution, transmission, and separation of FAIMS. Due to practical circuitry advantages, sinusoidal asymmetric waveforms are typically used in FAIMS, whereas theoretical studies indicate that square asymmetric waveforms improve ion separation, resolution, and sensitivity. Results from FAIMS using square and sinusoidal waveforms are presented, and effects of the waveforms on ion separation are discussed. A FAIMS system interfaced with a quadrupole ion trap mass spectrometer was used in this study. FAIMS spectra were generated by scanning the compensation voltage (CV) while operating the mass spectrometer in total ion mode. The identification of ions was accomplished through mass spectra acquired at fixed values of ions' CVs. Square waveform evaluation was done by acquiring data at three frequencies and six duty cycles of the square waveform generator. The performance of FAIMS using square and sinusoidal waveforms at 250, 333, and 500 kHz frequencies was compared, and trends were identified. For all frequencies, the best response of FAIMS was achieved at the lower amplitudes and under the lower duty cycles of the square waveform generator. The separation of FAIMS was better at the higher frequencies. These results demonstrate the potential to incorporate square-wave FAIMS into the design of a miniature device for detection of explosives in the field. SIMION version 8.0, the ion trajectory modeling program, was utilized to optimize the performance of the miniature FAIMS cell and to validate experimental results.

8.
Sci Rep ; 11(1): 23222, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34853361

RESUMEN

The mediated semi-quantum key distribution (MSQKD) protocol is an important research issue that lets two classical participants share secret keys securely between each other with the help of a third party (TP). However, in the existing MSQKD protocols, there are two improvable issues, namely (1) the classical participants must be equipped with expensive detectors to avoid Trojan horse attacks and (2) the trustworthiness level of TP must be honest. To the best of our knowledge, none of the existing MSQKD protocols can resolve both these issues. Therefore, this study takes Bell states as the quantum resource to propose a MSQKD protocol, in which the classical participants do not need a Trojan horse detector and the TP is dishonest. Furthermore, the proposed protocol is shown to be secure against well-known attacks and the classical participants only need two quantum capabilities. Therefore, in comparison to the existing MSQKD protocols, the proposed protocol is better practical.

9.
Front Psychol ; 12: 640115, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33708166

RESUMEN

Given the widespread acceptance of computational thinking (CT) in educational systems around the world, primary and higher education has begun thinking about how to cultivate students' CT competences. The artificial intelligence of things (AIoT) combines artificial intelligence (AI) and the Internet of things (IoT) and involves integrating sensing technologies at the lowest level with relevant algorithms in order to solve real-world problems. Thus, it has now become a popular technological application for CT training. In this study, a novel AIoT learning with Augmented Reality (AR) technology was proposed and explored the effect of CT skills. The students used AR applications to understand AIoT applications in practice, attempted the placement of different AR sensors in actual scenarios, and further generalized and designed algorithms. Based on the results of the experimental course, we explored the influence of prior knowledge and usage intention on students' CT competence training. The results show that proposed AIoT learning can increase students' learning intention and that they had a positive impact on problem solving and comprehension with AR technology, as well as application planning and design.

10.
Mol Biol Cell ; 18(10): 3711-22, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17634289

RESUMEN

Spermatogenesis in Marsilea vestita is a rapid process that is activated by placing dry microspores into water. Nine division cycles produce seven somatic cells and 32 spermatids, where size and position define identity. Spermatids undergo de novo formation of basal bodies in a particle known as a blepharoplast. We are interested in mechanisms responsible for spermatogenous initial formation. Mago nashi (Mv-mago) is a highly conserved gene present as stored mRNA and stored protein in the microspore. Mv-mago protein increases in abundance during development and it localizes at discrete cytoplasmic foci (Mago-dots). RNA interference experiments show that new Mv-mago protein is required for development. With Mv-mago silenced, asymmetric divisions become symmetric, cell fate is disrupted, and development stops. The alpha-tubulin protein distribution, centrin translation, and Mv-PRP19 mRNA distribution are no longer restricted to the spermatogenous cells. Centrin aggregations, resembling blepharoplasts, occur in jacket cells. Mago-dots are undetectable after the silencing of Mv-mago, Mv-Y14, or Mv-eIF4AIII, three core components of the exon junction complex (EJC), suggesting that Mago-dots are either EJCs in the cytoplasm, or Mv-mago protein aggregations dependent on EJCs. Mv-mago protein and other EJC components apparently function in cell fate determination in developing male gametophytes of M. vestita.


Asunto(s)
Marsileaceae/fisiología , Proteínas de Plantas/metabolismo , Espermatogénesis/fisiología , Secuencia de Aminoácidos , Anticuerpos/farmacología , ADN Complementario , Células Germinativas/citología , Células Germinativas/efectos de los fármacos , Marsileaceae/efectos de los fármacos , Datos de Secuencia Molecular , Proteínas de Plantas/química , Polen/citología , Polen/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Interferencia de ARN , Transporte de ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Espermatogénesis/efectos de los fármacos , Combinación Trimetoprim y Sulfametoxazol/metabolismo , Tubulina (Proteína)/metabolismo
11.
J Air Waste Manag Assoc ; 58(10): 1266-73, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18939773

RESUMEN

Volatile organic compounds (VOCs) are the cause of indoor air pollution and are readily emitted from furniture and cleaning agents. In Taiwan, the concentrations of indoor VOCs range roughly from 1 to 10 ppm. It is important to effectively reduce indoor VOC emissions and establish the implementation of long-term, low-cost, controlled techniques such as those found in the ultraviolet/titanium dioxide (UV/TiO2) control systems. This study evaluates the performance of a photoreactor activated by visible irradiation and packed with TiO2/quartz or TiO2/mobile catalytic material number 41 (MCM-41). The photocatalysts tested include commercial TiO2 (Degussa P-25) and synthesized TiO2 with a modified sol-gel process. The UV light had a wavelength of 365 nm and contained an 8-W, low-pressure mercury lamp. Reactants and products were analyzed quantitatively by using gas chromatography with a flame-ionization detector. It is important to understand the influence of such operational parameters, such as concentration of pollutant, temperature, and retention time of processing. The indoor concentrations of VOCs varied from 2 to 10 ppm. Additionally, the temperatures ranged from 15 to 35 degrees C and the retention time tested from 2 to 8.2 sec. The results show that quartz with TiO2 had a better photoreductive efficiency than quartz with MCM-41. The toluene degradation efficiency of 77.4% with UV/TiO2/quartz was larger than that of 54.4% with the UV/TiO2/MCM-41 system under 10-min reaction time. The degradation efficiency of the UV/TiO2 system decreased with the increasing concentrations of indoor VOCs. The toluene degradation efficiency at 2 ppm was approximately 5 times greater than that at 10 ppm. The photoreduction rate of the VOCs was also evaluated with the Langmuir-Hinshewood model and was shown to be pseudo-first-order kinetics.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/prevención & control , Cuarzo/química , Dióxido de Silicio/química , Titanio/química , Contaminación del Aire Interior/análisis , Catálisis , Fotoquímica , Temperatura , Rayos Ultravioleta
12.
Front Microbiol ; 6: 1320, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26648915

RESUMEN

On December 14, 2012, the FDA approved Raxibacumab, the first monoclonal antibody product developed under Project BioShield to achieve this milestone, and the first biologic product to be approved through the FDA animal efficacy rule (or "Animal Rule"). Raxibacumab is approved for the treatment of adult and pediatric patients with inhalational anthrax due to Bacillus anthracis in combination with appropriate antibiotic drugs and for prophylaxis of inhalational anthrax when alternative therapies are not available or not appropriate. The developmental process required for approval of Raxibacumab illustrates many of the challenges that product developers may encounter when pursuing approval under the Animal Rule and highlights a number of important regulatory and policy issues.

14.
Bioanalysis ; 4(11): 1363-75, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22720654

RESUMEN

Green chemistry is a way to avoid threats to human health and the environment in chemical processes, including analytical methodology. According to the 12 principles provided by ACS Green Chemistry Institute, first described by Anastas and Warner, prevention of waste generation should be first considered as an alternative to ways of treating waste. Therefore, analytical techniques that may reduce solvent waste are of great interest towards greener analysis. High-field asymmetric waveform ion mobility spectrometry (FAIMS) utilizes electrical fields to achieve separation, post an ionization source, and could provide an alternative method for separation and reduce solvent use in comparison with traditional HPLC methodologies. In this article, the operational principles and developments of FAIMS will be discussed, including the advantages of adding solvent vapor to the carrier gas. In addition, applications and challenges of implementing FAIMS technology will also be discussed.


Asunto(s)
Biomarcadores/análisis , Tecnología Química Verde , Espectrofotometría , Electrodos , Gases/química , Humanos , Iones/química , Espectrometría de Masas , Solventes/química
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