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Background The emergence of vancomycin-resistant Staphylococcus aureus (VRSA) represents a challenge for the treatment of staphylococcal infections in both human and animals worldwide. Although VRSA has been detected in several animal species worldwide, data on the bacterial prevalence in dromedary camels and workers in camel slaughterhouses are scarce. Methods We investigated meat samples from 200 dromedary camel carcasses from three different abattoirs that were being prepared to be sent to the markets. Twenty hand swabs were voluntarily collected from the workers in the same abattoirs. Isolation and identification of the bacterial specimens from the samples were performed using conventional cultural techniques and biochemical identification and were confirmed by PCR amplification of the nuc gene. Antimicrobial susceptibility against nine antimicrobial agents commonly used in human and camels was tested using the disc diffusion method, and genetic analysis was performed by evaluating the mecA gene in phenotypically oxacillin (OXA)- and cefoxitin (FOX)-resistant isolates. The resistance of S. aureus to vancomycin (VAN) was tested by broth microdilution and confirmed by PCR targeting the vanA and vanB genes. The vanA and vanB genes were sequenced. Result S. aureus was detected in both camel meat (29/200, 14.5%) and in abattoir workers (11/20, 55%). Of the collected samples, 27% (8/29, camel) and 54% (6/11, human) were identified as VRSA. All VRSA isolates carried both the vanA and vanB genes. Additionally, all VRSA isolates were also classified as methicillin-resistant S. aureus (MRSA). The vanA amplicons of the isolates from human and camel meat were homologous and clustered with a Chinese reference isolate sequence. Conclusion This study demonstrated that VRSA is present in camel abattoirs in Egypt. Zoonotic transmission between animals and human is probable and reflects both a public health threat and a food safety concern.

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Islanded microgrids do not have sufficient resources to contribute enough fault current to legacy protection devices to continue operation. Therefore, when a fault happens in an islanded microgrid, relays with high fault current setting will fail to detect and clear the fault. Contemporary adaptive protection schemes rely on communication technologies to adjust the relay settings to adapt to the microgrids' modes of operation; grid-connected or islanded. However, the risk of communication link failures and cyber security threats such as denial-of-service represent major challenges in implementing a reliable adaptive protection scheme. In order to address this issue, this paper proposes an adaptive protection scheme which utilize super capacitive energy storage to enhance resiliency against communication outages. This paper also introduces an autonomous control algorithm developed for the super-capacitor's AC/DC converter. The proposed control is capable of deciding upon charging, discharging of the super-capacitor, and whether or not to feed fault currents in the AC side, based on direct voltage and frequency measurements from its connection point with the microgrid. This eliminates the need for a control command to be sent from the point of common coupling of the microgrid with main grid to adjust the controller's mode of operation and thus reducing the risk of controller failure due to cyberattacks or other communication issues. Additionally, the paper proposes a solution to avoid installing a larger super-capacitor by temporarily disconnecting the uncritical pulsed load during the fault instant. The proposed protection scheme was investigated through simulation for various fault types and showed successful results using the proposed scheme in eliminating the aforementioned faults when the communication were available or attacked.

This paper provides an extensive review of the conducted research regarding various microgrids (MGs) control techniques and the impact of Information Communication Technology (ICT) degradation on MGs performance and control. Additionally, this paper sheds the light on the research gaps and challenges that are to be explored regarding ICT intrinsic-limitations impact on MGs operations and enhancing MGs control. Based on this assessment, it offers future prospects regarding the impact of ICT latencies on MGs and, consequently, on the smart grid. Finally, this paper introduces a case study to show the significance and examine the effect of wireless communication technologies latency on the converters and the DC bus voltage of a centralized controlled DC MG. A DC microgrid with its communication-based control scheme was modeled to achieve this goal. The MATLAB simulation results show that the latency impact may be severe on the converter switches and the DC bus voltage. Additionally, the results show that the latency impact varies depending on the design of the MG and its operational conditions before the latency occurs.

Standardization in smart grid communications is necessary to facilitate complex operations of modern power system functions. However, the strong coupling between the cyber and physical domains of the contemporary grid exposes the system to vulnerabilities and thus places more burden on standards' developers. As such, standards need to be continuously assessed for reliability and are expected to be implemented properly on field devices. However, the actual implementation of common standards varies between vendors, which may lead to different behaviors of the devices even if present under similar conditions. The work in this paper tested the implementation of the International Electro-technical Commission's Generic Object Oriented Substation Event GOOSE (IEC 61850 GOOSE) messaging protocol on commercial Intelligent Electronic Devices (IEDs) and the open source libiec61850 library-also used in commercial devices-which showed different behaviors in identical situations. Based on the test results and analysis of some features of the IEC 61850 GOOSE protocol itself, this paper proposes guidelines and recommendations for proper implementation of the standard functionalities.

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