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Multicontamination of soils by various organic and inorganic pollutants is considered as an obstacle for the development of hyperaccumulator plants and phytoextraction of metals. The aim of this study was to investigate the effect of polycyclic aromatic hydrocarbons (PAHs) in combination with trace elements on the antioxidant response and phytoextraction efficiency of two populations of the hyperaccumulator Noccaea caerulescens from either a metalliferous (Ganges) or a nonmetalliferous (Chavignée) site. Plants were grown for 17 days in soil containing moderate concentrations of trace elements and under the effect of phenanthrene (PHE), a PAH stress model. In general, exposure to PHE resulted in a reduction of growth parameters, together with the upregulation of antioxidant enzymes and compounds and limitations in nutrient uptake and heavy metal extraction in N. caerulescens. Variations were observed in the extent of enzymatic activities and the amount of metals extracted between the two populations studied. Plants from Chavignée exhibited a slightly more tolerant response to PHE stress than those from Ganges. The presence of PHE in the soil proved highly toxic to N. caerulescens, resulting in low numbers of survivors. Nevertheless, the differences observed between the two populations with regard to growth, metal extraction, and antioxidant defense responses suggest that the difference in defense capacity may ensure different tolerance. This difference may be linked to adaptations acquired by each population according to the soil type from which it originates. However, these results need to be confirmed by further experiments. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Coronavirus disease 2019 (COVID-19) has profoundly impacted residency and fellowship training and education. However, how and to what extent the COVID-19 pandemic in Lebanon compromised the daily involvement of trainees on the clinical and ethical levels is currently unknown, which this study will shed light on. METHODS: We conducted a cross-sectional survey (30 questions) targeting medical residents delivering healthcare services in Lebanon. Residents from different specialties were included in the study to assess the effect of the pandemic on their education and the ethical obstacles they faced when dealing with patients. RESULTS: A total of 221 postgraduate medical students participated in our study. Results showed that about half of the residents (52.1%) were only able to do a basic physical examination rather than a full examination as a mandatory requirement in the residency curriculum. The majority (60%) agreed that the doctor–patient relationship is contravened. In addition, almost all residents suffered from fear and emotional distress that affected their education (83.7%). CONCLUSION: The findings of this study identify the effect of COVID-19 on residents' training, which affects treatment outcomes and greatly impacts the mental well-being of both healthcare workers and patients. [ABSTRACT FROM AUTHOR]

This research examines two neglected areas in international advertising campaigns: (1) the impact of managers' cultural orientations on agency selection and (2) the relationships between managers' perceptions of factors of media selection and agency selection. Data were generated from a mail survey to American advertising executives whose firms sell consumer durable goods in overseas markets. The findings reveal: (1) culturally-oriented managers, more than non-culturally oriented managers, use foreign advertising agencies and (2) managers' perceptions of general and specific factors of media selection do not influence their selection of advertising agencies. Keywords: advertising agency selection, international markets, cultural factors, INTRODUCTION The world has become a global market. Many companies now sell their products, services, and ideas to as many customers as possible. They depend heavily on foreign markets and [...]

We propose a verifiable (t,n)-threshold secret sharing scheme using Lagrange interpolation and secure cryptographic hash functions. This scheme is an improvement of Shao’s scheme [Inform. Sci. 278 (2014) 104–109]. In our variant, verification of shares is achieved through computation of their multiplicative inverses in conjunction with a secure hash function such as SHA-3. This idea results in a significant size reduction, in comparison with Shao’s scheme, to the shares assigned to each participant. Applications of the proposed scheme include sharing of cryptographic keys, access codes, etc. Furthermore, we improve our construction to present a method for secret sharing with adjustable access structure. This can further be extended to a secret sharing scheme with essential participants, where any authorized set of participants must meet a threshold in the number of essential participants it contains. While our proposal has smaller share sizes compared to Shao’s scheme, it also adds the capabilities of changeable parameters and essential participants. [ABSTRACT FROM AUTHOR]

Background: The immune system of honeybees includes multiple pathways that may be affected by pesticide exposure decreasing the immune competencies of bees and increasing their susceptibility to diseases like the fungal Nosema spp. infection, which is detected in collapsed colonies. Methods: To better understand the effect of the co-presence of multiple pesticides that interact with bees like imidacloprid and amitraz, we evaluated the expression of immune-related genes in honeybee hemocytes. Results: Imidacloprid, amitraz, and the immune activator, zymosan A, mainly affect the gene expression in the Toll pathway. Discussion: Imidacloprid, amitraz, and zymosan A have a synergistic or an antagonistic relationship on gene expression depending on the level of immune signaling. The presence of multiple risk factors like pesticides and pathogens requires the assessment of their complex interaction, which has differential effects on the innate immunity of honeybees as seen in this study. [ABSTRACT FROM AUTHOR]

Many traditional forms of advertising are losing ground to alternative media. Such a trend represents opportunities for the promotional products medium. However, the effectiveness of promotional products in comparison to other advertising alternatives has not been widely empirically tested. This experiment examines responses to advertising media by employing two sets of seven randomly assigned conditions at two major U.S. universities. The findings revealed statistically significant effective improvements in contrast to television advertising when promotional products were used in credibility perceptions, attitudes towards the advertisement and the product, and behavioural intents such as purchasing intent and referral intent. Additionally, positive effects were observed when promotional products were used in conjunction with television and print advertising compared with television and print advertising alone. Future directions for research are recommended. [ABSTRACT FROM AUTHOR]

Simple Summary: Pesticide exposure is a risk factor affecting insect immune response and may participate in honeybee colony deaths. Changes in the immune response may hinder insects more susceptible to diseases and increase the risk of pathogen infection and pest resistance. We found that imidacloprid and amitraz alter the oxidative response of insect hemocytes at different concentrations of the immune stimulator, zymosan A. There is a differential effect of imidacloprid and amitraz on hemocytes of insects from different orders and their effect on oxidative response in insects persists beyond the point of early contact with zymosan A. Invertebrates have a diverse immune system that responds differently to stressors such as pesticides and pathogens, which leads to different degrees of susceptibility. Honeybees are facing a phenomenon called colony collapse disorder which is attributed to several factors including pesticides and pathogens. We applied an in vitro approach to assess the response of immune-activated hemocytes from Apis mellifera, Drosophila melanogaster and Mamestra brassicae after exposure to imidacloprid and amitraz. Hemocytes were exposed to the pesticides in single and co-exposures using zymosan A for immune activation. We measured the effect of these exposures on cell viability, nitric oxide (NO) production from 15 to 120 min and on extracellular hydrogen peroxide (H2O2) production after 3 h to assess potential alterations in the oxidative response. Our results indicate that NO and H2O2 production is more altered in honeybee hemocytes compared to D. melanogaster and M. brassicae cell lines. There is also a differential production at different time points after pesticide exposure between these insect species as contrasting effects were evident with the oxidative responses in hemocytes. The results imply that imidacloprid and amitraz act differently on the immune response among insect orders and may render honeybee colonies more susceptible to infection and pests. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.compeleceng.2010.02.004 Byline: Ali Kanso Keywords: Stream ciphers; Linear feedback shift registers; m-Sequences; Self-shrinking generators Abstract: The self-shrinking generator SSG, an elegant keystream generator proposed by Meier and Staffelbach, is built up from a single n-stage primitive linear feedback shift register (LFSR) to produce a keystream of period P[greater than or equal to]2.sup.(n/2), and linear complexity greater than half its period. In this article, we propose a new variant of the self-shrinking generator called the modified self-shrinking generator MSSG. This new generator is based on a primitive n-stage LFSR and uses an extended selection rule based on the XORed value of a pair of bits. We prove that the keystreams of the MSSG are balanced, and have period greater than or equal to 2.sup.(n/3), linear complexity greater than half the period, and possess good statistical properties. We investigate the security of the generator against various powerful cryptanalytic attacks. We show that the MSSG is more secure than the SSG against most of these attacks. Moreover, experiments show that for odd values of n, 3 Author Affiliation: Department of Mathematics and Computer Science, College of Science, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait Article History: Received 16 December 2008; Revised 6 January 2010; Accepted 15 February 2010 Article Note: (footnote) [star] Reviews processed and proposed for publication to the Editor-in-Chief by Associate Editor Dr. M. Malek.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.compeleceng.2009.08.005 Byline: Ali A. Kanso Keywords: Cryptography; Security; Stream ciphers; Feedback shift registers; Alternating step generator Abstract: Encryption in wireless communication systems is an extremely important factor to protect information and prevent fraud. In this paper, we propose a new encryption system for use in stream cipher applications. The design proposed is intended for hardware implementation and based on (n+1) feedback shift registers interconnected in such a way that one register controls the clocking of the other n registers. The aim of this construction is to allow the production of a large family of distinct keystreams when the initial states and feedback functions of the feedback shift registers are unchanged. The produced keystreams are shown to possess the basic security requirements for cryptographic sequences such as long period, high linear complexity and good statistical properties, provided that suitable parameters are chosen. Furthermore, the design is shown to resist various types of cryptanalytic attacks. These characteristics and properties enhance its use as a suitable encryption system for stream cipher applications. Author Affiliation: Department of Mathematics and Computer Science, College of Science, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait Article History: Received 29 December 2008; Revised 14 June 2009; Accepted 9 August 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.compeleceng.2008.09.001 Byline: Ali A. Kanso Keywords: Cryptography; Security; Stream ciphers; Linear feedback shift registers; Shrinking generator Abstract: The need for wireless communication systems has increased rapidly in the past few years and wireless communication has become more convenient in business and society. However, the air interface is vulnerable to eavesdropping, hence encryption in wireless communication systems is a necessity to keep sensitive information confidential and to prevent fraud. Furthermore, wireless devices such as Bluetooth devices and mobile phones require an encryption algorithm that is secure, fast and simple to implement. There are several cryptosystems for stream cipher applications such as A5/x used in GSM mobile communications. However, A5/x are vulnerable to cryptanalytic attacks. In this paper, a new clock-controlled cryptosystem intended for hardware implementation is proposed. The design has attractive properties such as simplicity and scalability. The cryptographical properties including period, balancedness, linear complexity and probability distribution are analyzed. The design provides the basic security requirements, and is resistant to known cryptanalytic attacks. It is shown that the irregular clocking introduced provides a certain level of strengthened security against several cryptanalytic attacks. These properties enhance its use as a suitable cryptosystem for stream cipher applications. Author Affiliation: Department of Mathematics and Computer Science, College of Science, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait Article History: Received 24 December 2007; Accepted 3 September 2008

This paper proposes a probabilistic image encryption scheme that improves on existing deterministic schemes by using a chaining mode of chaotic maps in a permutation-masking process. Despite its simplicity, the permutation phase destroys any correlation between adjacent pixel values in a meaningful image. The masking phase, however, modifies the pixel values of the image at hand using pseudorandom numbers with some other initiated random numbers so that any slight change in the plain image spreads throughout the corresponding cipher image. These random numbers ensure the generation of distinct cipher images for the same plain image encryption, even if it is encrypted multiple times with the same key, thereby adding some security features. Simulations show that the proposed scheme is robust to common statistical and security threats. Furthermore, the scheme is shown to be competitive with existing image encryption schemes. [ABSTRACT FROM AUTHOR]

Since the establishment of its Orlando theme park and resort in 1971, Walt Disney World has maintained a seemingly-consistent reputation for offering exciting adventures in a secure environment. However, the death of 2-year-old Lane Thomas Graves in a Disney resort lagoon has proven that nothing is impenetrable, not even the Disney empire. On June 14, 2016, Graves was attacked and killed by an alligator at the Seven Seas Lagoon at Disney World’s Grand Floridian Hotel in Orlando. This case study evaluates Disney’s public relations activities to remedy the tragic accident. The authors followed the ROPE model of public relations in their analysis. They noted that the public relations team at Disney overlooked the resort employees and people who witnessed the accident, and the objectives were neither measurable nor time-bound. In response to the accident, two executives immediately offered heartfelt expressions of sympathy to the Graves family and personalized their expressions. The authors concluded that the public relations team’s handling of the backlash had strengths as well weaknesses. No research has deeply and immediately examined the damage intensity. Four years after the incident, however, the authors conducted an online survey to probe into people’s awareness and attitudes. The findings reveal that 35% of the respondents recalled the alligator’s attack, 11% claimed that the incident affected their views of Disney brand, 27% stated that the incident impacted their attitudes toward the Disney’s Grand Floridian Resort, and 86% claimed that they would still attend Disney World or any of their parks and resorts. [ABSTRACT FROM AUTHOR]

The Deepwater Horizon oil spill, also known as the British Petroleum (BP) oil spill, is considered the largest marine accident in the history of the industry. The 2010 incident in the Gulf of Mexico resulted in the killing of 11 crew members, posing serious health risks to thousands of people and creating massive damages to wildlife habitats and fishing and tourism industries. This case study investigates how British Petroleum dealt with the crisis that left lasting serious negative impacts on its brand and reputation. The investigation reveals that BP used a wide range of public relations activities to rebuild its reputation, but the company was not well prepared to handle such a disaster. The authors report that BP also originally made grave mistakes in: (1) trying to spin its way of the crisis rather than tackling the challenges head on and (2) focusing heavily on advertising during the clean-up operation. The authors conclude that BP's corporate brand continues to lag behind that of competitors such as Shell and Exxon, but that a change in company leadership has undertaken a more ethical communication strategy that is showing signs of success. [ABSTRACT FROM AUTHOR]

This paper proposes a new family of 4-dimensional chaotic cat maps. This family is then used in the design of a novel block-based image encryption scheme. This scheme is composed of two independent phases, a robust light shuffling phase and a masking phase which operate on imageblocks. It utilizes measures of central tendency to mix blocks of the image at hand to enhance security against a number of cryptanalytic attacks. The mixing is designed so that while encryption is highly sensitive to the secret key and the input image, decryption is robust against noise and cropping of the cipher-image. Empirical results show high performance of the suggested scheme and its robustness againstwell-known cryptanalytic attacks. Furthermore, comparisons with existing image encryption methods are presented which demonstrate the superiority of the proposed scheme. [ABSTRACT FROM AUTHOR]

Im Zuge der Produktionsdigitalisierung werden mehr Daten aufgenommen und ausgewertet. Neue Roboter besitzen eine integrierte Drehmomentsensorik. Diese erfasst nicht nur interne Roboterdaten, sondern auch externe Einflüsse. Diese Daten können zur Inbetriebnahme von Prozessen oder zur Aussage der Qualität verwendet werden. Um den Roboter als Messgerät einzubinden, bedarf es einer Untersuchung der Genauigkeit der integrierten Drehmomentsensoren. Zur Untersuchung wurde eine Vorgehensweise entwickelt, welche zwei vorhandene Methoden aus unterschiedlichen Disziplinen miteinander kombiniert. Zum einen wird die Methode DMAIC aus dem Qualitätsmanagement zur Strukturierung der Untersuchung und zum anderen wird der Eignungsnachweis von Prüfprozessen zur inhaltlichen Ermittlung von Wissen verwendet. Durch einen Versuchsaufbau mit Gewichtskräften am Endeffektor des Roboters werden die systematische und zufällige Messabweichung der Drehmomentsensoren im Roboter bestimmt. Ziel dieses Papers ist die Analyse des Einsatzes eines Roboters mit integrierten Drehmomentsensoren als Messmittel im Montageprozess. Als ein Anwendungsfall wird die Erfassung der dynamischen Parameter eines Roboterwerkzeuges beschrieben. Gleichzeitig wurde eine neue Methodik zur Parametererfassung entwickelt, die im Vergleich zur Standardvorgehensweise deutliches Verbesserungspotenzial hinsichtlich der Genauigkeit aufweist. In the course of production digitization, more data is recorded and evaluated. New robots have integrated torque sensors. The latter records internal robot data and external influences. These data can be used for the commissioning processes or for quality control. Therefore, processes become more transparent and quantifiable. In order to integrate the robot as a measuring device, it is necessary to examine the suitability of the investigation procedure. A novel approach was developed for the investigation, which combines two existing methods from different disciplines. On the one hand, the DMAIC method from quality management is used to structure the investigation and on the other hand, the test process suitability is used for the substantial determination of knowledge. In order to determine the systematic and random measurement error of the robot, results are identified by a test setup. The aim of this paper is to analyse the use of a robot with integrated torque sensors as a measuring device in the assembly process. As an application of a robot with measuring ability, the identification of the dynamic parameters of a robot tool is described. For this purpose, a new innovative methodology was developed, which shows clear improvement potential in comparison to the conventional method. [ABSTRACT FROM AUTHOR]

A (k, n)-threshold secret image sharing scheme is any method of distributing a secret image amongst n participants in such a way that any k participants are able to use their shares collectively to reconstruct the secret image, while fewer than k shares do not reveal any information about the secret image. In this work, we propose a lossless linear algebraic (k, n)-threshold secret image sharing scheme. The scheme associates a vector vi to the ith participant in the vector space Fk2α , where the vectors vi satisfy some admissibility conditions. The ith share is simply a linear combination of the vectors vi with coefficients from the secret image. Simulation results demonstrate the effectiveness and robustness of the proposed scheme compared to standard statistical attacks on secret image sharing schemes. Furthermore, the proposed scheme has a high level of security, errorresilient capability, and the size of each share is 1/k the size of the secret image. In comparison with existing work, the scheme is shown to be very competitive. [ABSTRACT FROM AUTHOR]

On April, 17, 2018, Southwest Airlines flight 1380 experienced an uncontained engine failure after departing from New York-LaGuardia Airport on a flight to Dallas Love Field. This case study probes into the public relations efforts that Southwest Airlines pursued to manage the crisis after the aircraft was substantially damaged. The authors followed the Hendrix Process Model of public relations case study analysis, which applies the mnemonic "ROPE" (Research, Objectives, Programming, and Evaluation) as a template to evaluate the public relations initiative. Based on available evidence, Southwest Airlines sought to reduce negative media publicity and assure customers, flight attendants, and pilots that its airlines are safe. The company also attempted to inform the media that investigations were taking place to determine what went wrong and to assure the flight 1380 passengers that the company supports them. Southwest Airlines took actions that corresponded with their objectives. While the flight 1380 was still in the air, the company tweeted and posted on social media news about the incident progress. This action allowed Southwest Airlines to keep the media updated in a prompt and easy way. Scholars considered the Southwest Airlines incident to be one of the best handled public relations crises in 2018--ainly because the details were carefully planned before the crisis struck. However, the authors concluded that Southwest Airlines could have done more for their publics. For example, they could have had a central message to assure all concerned parties that the company is doing everything possible to guarantee their safety. [ABSTRACT FROM AUTHOR]

Adverting standardization has been widely discussed since 1990s. Recently, this discussion has been extended to mobile advertising. When it comes to adopt a standardization or localization strategy, it is important that marketers understand how mobile advertising is perceived in different markets. This study examines the impacts of four perceived values of mobile advertising on young Australian and Chinese consumers' acceptance of mobile advertising. The findings suggest that perceived functional value have the most positive effect on mobile advertising acceptance, followed by credibility and interactivity value. Further analyses reveal that culture moderates the relationships between perceived values and advertising acceptance. [ABSTRACT FROM AUTHOR]