Transmission Opportunities Research Articles

Syndromic surveillance during 2022 Uganda Martyrs' commemoration.

Mass gatherings frequently include close, prolonged interactions between people, which presents opportunities for infectious disease transmission. Over 20,000 pilgrims gathered at Namugongo Catholic and Protestant shrines to commemorate 2022 Uganda Martyr's Day. We described syndromes suggestive of key priority diseases particularly COVID-19 and viral hemorrhagic fever (VHF) among visiting pilgrims during May 25-June 5, 2022. We conducted a survey among pilgrims at the catholic and protestant shrines based on signs and symptoms for key priority diseases: COVID-19 and VHF. A suspected COVID-19 case was defined as acute respiratory illness (temperature greater 37.5°C and at least one sign/symptom of respiratory infection such as cough or shortness of breath) whereas a suspected VHF case was defined as fever >37.5°C and unexplained bleeding among pilgrims who visited Namugongo Catholic and Protestant shrines from May 25 to June 5, 2022. Pilgrims were sampled systematically at entrances and demarcated zonal areas to participate in the survey. Additionally, we extracted secondary data on pilgrims who sought emergency medical services from Health Management Information System registers. Descriptive analysis was conducted to identify syndromes suggestive of key priority diseases. Among 1,350 pilgrims interviewed, 767 (57%) were female. The mean age was 37.9 (±17.9) years. Nearly all pilgrims 1,331 (98.6%) were Ugandans. A total of 236 (18%) reported ≥1 case definition symptom and 42 (3%) reported ≥2 symptoms. Thirty-nine (2.9%) were suspected COVID-19 cases and three (0.2%) were suspected VHF cases from different regions of Uganda. Among 5,582 pilgrims who sought medical care from tents, 628 (11.3%) had suspected COVID-19 and one had suspected VHF. Almost one in fifty pilgrims at the 2022 Uganda Martyrs' commemoration had at least one symptom of COVID-19 or VHF. Intensified syndromic surveillance and planned laboratory testing capacity at mass gatherings is important for early detection of public health emergencies that could stem from such events.

P1121 The risk of inflammatory bowel disease following serious infectious mononucleosis: A Danish nested case-control study

Abstract Background Epstein-Barr virus (EBV) infects ~95% of adults globally and limited early life transmission opportunities can delay EBV exposure till adolescence/early adulthood, increasing the risk of severe EBV infection, which most commonly manifests as infectious mononucleosis (IM). This study sought to investigate a potential aetiological association between IM and inflammatory bowel disease (IBD). Methods In this longitudinal nested case-control study, Danish nationwide registries were used to identify 37,156 IBD patients and 222,936 sex- and age-matched healthy controls, between 2005-2021. Logistic regression was used to calculate the odds ratio (OR) for IM hospitalisation prior to IBD diagnosis stratified by sex, age at IM diagnosis, age at IBD diagnosis, and IBD subtype (Crohn’s disease [CD] or ulcerative colitis [UC]). Additionally, exposure-controlled time-to-event analyses were used to explore the association between IM hospitalization and poor IBD prognosis. This association was measured using the occurrence of IBD-related hospitalization, surgery, complication and/or anti-TNF therapy commencement up to 10 years post-IBD diagnosis. Results Previous IM hospitalisation was significantly associated with the development of both CD (OR: 1.44, 95% CI: 1.20-1.73) and UC (OR: 1.27, 95% CI: 1.09-1.47). Sex was not found to be a significant effect modifier of this association for either CD (p=0.4) or UC (p=0.9). Those hospitalised with IM at a younger age had a higher odd of developing CD than those hospitalised in early adulthood (0-14-years OR: 2.60 [95% CI: 1.41-4.59]; >20-years OR: 2.04 [95% CI: 1.23-3.25]). A similar pattern was observed for UC development (0-14-years OR: 2.62 [95% CI: 1.44-4.55]; >20-years OR: 1.50 [95% CI: 0.97-2.25]). Poor disease prognosis following hospitalisation with IM within 10 years post-IBD diagnosis was only seen in CD (CD IRR: 1.52 [95% CI: 1.20-1.92]; UC IRR: 0.87 [95% CI: 0.65-1.16]). Conclusion This study demonstrated an association between IBD development and prior hospitalisation with IM, indicating the possibility of EBV infection as a significant contributor to IBD development. Strengthening understanding of IBD development can contribute to the prevention of IBD and improve management.

Spray: A Spectrum-efficient and Agile Concurrent Backscatter System

Recent works have achieved considerable success in improving the concurrency of backscatter network. However, they do not optimize the balance between throughput and spectrum occupancy, both of which serve as pivotal parameters in concurrent transmissions. Moreover, these works also introduce complex components on tag thereby increasing both power consumption and deployment costs. In this article, we proposeSpray, a tag-lightweight system to achieve high throughput and narrow-band occupancy with low power. The key idea is to incorporate an agile channel allocating and scheduling mechanism into the backscatter network. This approach allows for efficient spectrum utilization and concurrency without the need for energy-intensive components. To optimize throughput in the presence of the challenge of harmonic interference, we introduce a novel algorithm that determines the channels with an optimal combination of central frequencies and bandwidths. Additionally, we propose a fair scheduling strategy to ensure equitable transmission opportunities for all tags. We prototype theSpraytag using commercial off-the-shelf components and implement the excitation and receiver with software-defined radio platform. Our evaluation shows that the system supports 30 parallel tags transmitting in the bandwidth of 600 kHz and the throughput can reach more than 280 kbps.

Epidemiological, and molecular investigation of Canine parvovirus-2 infection in Egypt.

Canine parvovirus enteritis (CPE) is a contagious viral disease of dogs caused by the canine parvovirus-2 (CPV-2) associated with high morbidity and mortality rates. CPV-2 has a high global evolutionary rate. Molecular characterization of CPV-2 and understanding its epidemiology are essential for controlling CPV-2 infections. This study examined the risk factors and survival outcomes of dogs infected with CPV-2. Molecular characterization of CPV-2 genotypes circulating in Egypt was performed to determine the evolution of CPV-2 nationally and globally. An age-matched case-control study was conducted on 47 control and 47 CPV-infected dogs. Conditional logistic regression analysis examined the association between the potential risk factors and CPE in dogs. Survival analysis was performed to determine the survival pattern of the infected dogs. Thirteen fecal samples from infected dogs were collected to confirm the CPV genotype by CPV-2 VP2 gene sequencing, assembly of nucleotide sequences, and phylogenic analysis. Unvaccinated and roamer dogs had eight and 2.3 times higher risks of CPV infection than vaccinated dogs and non-roamer dogs, respectively. The risk of death from CPE was high among dogs without routine visits to veterinary clinics and among non-roamer dogs. Molecular characterization of CPV-2 confirmed its genotype identity and relationship with the CPV-2 c and b clade types. This study highlights the potential factors for CPE control, especially vaccination and preventing dogs from roaming freely outside houses. Isolated CPV genotypes are closely related to southern Asian genotypes, suggesting a substantial opportunity for global transmission.

Ensuring the employer's right to information protection: problems of legal regulation

In the context of the rapid development of information and communication technologies and the proclamation of the constitutional right of everyone to freely search, receive and disseminate information, it is becoming increasingly difficult to restrict access to information of various kinds. Meanwhile, the confidential information at the disposal of the employer, access to which he restricts either in his own interests (commercial secret), or in the public interest or in the interests of third parties (information that has a secret regime, personal data of individuals) needs protection. The subject of the study is the provisions of the legislation, including labor legislation, which allow the employer, as the owner of confidential information, to build a system of limited access to it and take measures against employees who violate the established rules for protecting information. An analysis of the relevant norms leads to the conclusion that in the rapidly developing information society, which provides ample opportunities for the instant transmission (distribution) of a significant amount of information, the current legal regulation does not fully meet the requirements for balancing the rights and legitimate interests of the employee and the employer, since it allows the employer to stop the employee's access to protected information only by dismissing him on a disciplinary basis, which forces the employer to make such decisions even in cases where there are no grounds for this fixed by law (disclosure), thereby violating the rights of the employee. In this regard, it is proposed to introduce a legal mechanism for depriving an employee of access to confidential information when he commits actions that create a threat of its dissemination, which, on the one hand, will exclude him from working with such information, and on the other hand, will allow him (under certain conditions) to continue work for this employer. Such a mechanism, being aimed at optimal reconciliation of the interests of employers and employees, will ensure the right of the employer to the protection of information and at the same time will not allow excessive restriction of the rights of the employee.

CMUT as a Transmitter for Microbubble-Assisted Blood-Brain Barrier Opening.

Focused ultrasound (FUS) combined with microbubbles (MBs) has emerged as a promising strategy for transiently opening the blood-brain barrier (BBB) to enhance drug permeability in the brain. Current FUS systems for BBB opening use piezoelectric transducers as transmitters and receivers. While capacitive micromachined ultrasonic transducers (CMUTs) have been suggested as an FUS receiver alternative due to their broad bandwidth, their capabilities as transmitters have not been investigated. This is mainly due to the intrinsic nonlinear behavior of CMUTs, which complicates the detection of MB generated harmonic signals and their low-pressure output at FUS frequencies. Various methods have been proposed to mitigate CMUT nonlinearity; however, these approaches have primarily targeted contrast enhanced ultrasound imaging. In this study, we propose the use of polyphase modulation (PM) technique to isolate MB emissions when CMUTs are employed as transmitters for BBB opening. Our calculations for a human scale FUS system with multiple CMUT transmitters show that 10-kPa peak negative pressure (PNP) at 150-mm focal distance will be sufficient for MB excitation for BBB opening. Experimental findings indicate that this pressure level can be easily generated at 400-800 kHz using a readily available CMUT. Furthermore, more than 50-dB suppression of the fundamental harmonic signal is obtained in free field and transcranial hydrophone measurements by processing receive signals in response to phase-modulated transmit waveforms. In vitro validation of PM is also conducted using Definity MB flowing through a tube phantom. MB-filled tube phantoms show adequate nonlinear signal isolation and SNR for MB harmonic detection. Together our findings indicate that PM can effectively mitigate CMUT harmonic generation, thereby creating new opportunities for wideband transmission and receive operation for BBB opening in clinical and preclinical applications.

Designing Iterative Learning Schemes for Cooperative-Antagonistic Systems With Random Access Communication Protocols.

In this article, the design issue for an iterative learning controller is investigated for the cooperative-antagonistic system under the scheduling effects of random access protocol (RAP). In order to reflect the heterogeneous characteristic of the underlying system, the dynamics of each node in the cooperative-antagonistic system are described by a two-time-scale system. For the purpose of avoiding data collisions in signal transmissions, the so-called RAP is introduced to schedule the data exchanges among nodes, where the transmission opportunities of nodes are modeled by a sequence of random variables with certain transition probabilities. Considering that the mutual relationships may be cooperative and also competitive among nodes in many real-world networks, a novel cooperative-antagonistic-based iterative learning controller is developed to handle the tracking problem of the system dynamics. Sufficient conditions are obtained for the design of the controller parameters. Furthermore, the derived results are extended to the case that the transition probabilities for the RAP are partially unknown. Finally, a numerical example is presented to illustrate the effectiveness of the proposed iterative learning control (ILC) scheme.

Beyond Wi-Fi 7: Spatial reuse through multi-AP coordination

Wi-Fi 7, based on the IEEE 802.11be amendment, is designed to increase the maximum achievable throughput, expand the range of operating frequencies, and improve latency and jitter in worst-case scenario. In the context of the discussions to shape what Wi-Fi 8 will be, the IEEE 802.11 WG is evaluating multi-AP coordination as a strategy to further improve network performance in several aspects. MAC-driven multi-AP coordination strategies include coordinated Orthogonal Frequency Division Multiple Access (c-OFDMA), coordinated Time Division Multiple Access (c-TDMA), and coordinated Spatial Reuse (c-SR). In c-OFDMA, a set of APs transmit during a Transmission Opportunity on different channels, whereas in c-TDMA, the APs take turns transmitting on the same channel during a Transmission Opportunity. Instead, in c-SR, a set of APs transmit simultaneously on the same channel and during the same Transmission Opportunity.In this paper, we focus on c-SR. We introduce a c-SR interference model and present a strategy based on the proposed model for estimating groups of APs that can transmit successfully simultaneously. We implemented the proposed approach in the multi-AP coordination framework of ns-3 that we developed to analyze c-TDMA. We then thoroughly evaluate the performance of the proposed c-SR scheme via ns-3 simulations. The proposed scheme allows increasing the system throughput of a dense deployment up to 2.3 times as well as substantially reducing the Head of Line delay.

Non-Indigenous and Indigenous food-related interactions: How does the transmission of a normativity perpetuate colonialism?

Type 2 diabetes has been considered an epidemic among Indigenous Peoples in Canada. They also suffer more from obesity than non-Indigenous people in the country, a condition that is considered an epidemic worldwide. Various public health and social services professionals are working in Indigenous communities across the country to raise awareness about certain lifestyle habits. The main objective of this article is to analyze the food normativity transmitted to an Indigenous population and to examine its reception. More specifically, the aim is to understand the opportunities of transmission (content and format) and the relational dynamics that these encounters between mostly non-Indigenous professionals and Indigenous Peoples imply. The analysis is based on an ethnographic fieldwork in the Anicinabe community of Lac Simon (Abitibi, Quebec). Conducted with a relational approach, interviews and participant observation were carried out. It appears that the Anicinabek have a great knowledge of the "good" eating habits as defined by a biomedical food normativity. A reflexive analysis of my presence in the community as a non-Indigenous anthropologist and an analysis of the Anicinabek's responses to food recommendations lead me to argue that a form of food colonialism, inscribed in welfare (assistance) colonialism, persists while food surveillance seems to be integrated by the Anicinabek. This food normativity is the bearer of a biomedical conception of food and the colonial history of the country colours its transmission to Indigenous Peoples. Greater autonomy, namely Indigenous food sovereignty, seems necessary to deconstruct this food assistance structure.

Gut microbiota in the short-beaked echidna(Tachyglossus Aculeatus) shows stability across gestation.

Indigenous gut microbial communities (microbiota) play critical roles in health and may be especially important for the mother and fetus during pregnancy. Monotremes, such as the short-beaked echidna, have evolved to lay and incubate an egg, which hatches in their pouch where the young feeds. Since both feces and eggs pass through the cloaca, the fecal microbiota of female echidnas provides an opportunity for vertical transmission of microbes to their offspring. Here, we characterize the gut/fecal microbiome of female short-beaked echidnas and gain a better understanding of the changes that may occur in their microbiome as they go through pregnancy. Fecal samples from four female and five male echidnas were obtained from the Currumbin Wildlife Sanctuary in Queensland and sequenced to evaluate bacterial community structure. We identified 25 core bacteria, most of which were present in male and female samples. Genera such as Fusobacterium, Bacteroides, Escherichia-Shigella, and Lactobacillus were consistently abundant, regardless of sex or gestation stage, accounting for 58.00% and 56.14% of reads in male and female samples, respectively. The echidna microbiome remained stable across the different gestation stages, though there was a significant difference in microbiota composition between male and female echidnas. This study is the first to describe the microbiome composition of short-beaked echidnas across reproductive phases and allows the opportunity for this novel information to be used as a metric of health to aid in the detection of diseases triggered by microbiota dysbiosis.

Transmission mode predicts coinfection patterns of insect-specific viruses in field populations of the Queensland fruit fly.

Insect-specific viruses (ISVs) can affect insect health and fitness, but can also interact with other insect-associated microorganisms. Despite this, ISVs are often studied in isolation from each other, in laboratory populations. Consequently, their diversity, prevalence and associations with other viruses in field populations are less known, yet these parameters are important to understanding virus epidemiology. To help address this knowledge gap, we assessed the diversity, prevalence and coinfections of three ISVs (horizontally transmitted cripavirus, biparentally transmitted sigmavirus and maternally transmitted iflavirus) in 29 field populations of Queensland fruit fly, Australia's most significant horticultural pest, in the context of their different transmission modes. We detected new virus variant diversity. In contrast to the very high virus prevalence in laboratory populations, 46.8% of 293 field flies carried one virus and 4.8% had two viruses. Cripavirus and sigmavirus occurred in all regions, while iflavirus was restricted to subtropical and tropical regions. Cripavirus was most prevalent (37.5%), followed by sigmavirus (13.7%) and iflavirus (4.4%). Cripavirus coinfected some flies with either one of the two vertically transmitted viruses. However, sigmavirus did not coinfect individuals with iflavirus. Three different modelling approaches detected negative association patterns between sigmavirus and iflavirus, consistent with the absence of such coinfections in laboratory populations. This may be linked with their maternal transmission and the ineffective paternal transmission of sigmavirus. Furthermore, we found that, unlike sigmavirus and iflavirus, cripavirus load was higher in laboratory than field flies. Laboratory and mass-rearing conditions may increase ISV prevalence and load due to increased transmission opportunities. We conclude that a combination of field and laboratory studies is needed to uncover ISV interactions and further our understanding of ISV epidemiology.

1891. Descriptive Epidemiology of African-American Patients with Tuberculosis in in Detroit

Abstract Background Knowing local risk factors for tuberculosis (TB) facilitates identification of individuals with latent or active TB. The purpose of this study is to describe the epidemiology of TB among patients seen in the Detroit Health Department. We will refer to our study population as Detroit TB cases. Methods A retrospective descriptive study was conducted in collaboration with the Michigan Department of Health and Human Services. TB data submitted to MDHHS from Detroit between January 2017 and December 2022 was evaluated. Information on demographics, genotype clusters, and clinical / lifestyle risk factors was collected Results One-hundred forty-one TB cases were verified in Detroit during the study period and will be referred to as the study population. See Table 1 for baseline demographics. Sixty percent (85) of cases were males. Fifty-eight % (81) were Black / African American (B/AA). Sixty-two % (87) of cases were born in the U.S. Of persons with positive cultures for TB, 45% (37) were in a genotype cluster. Please see figure 1 for example of genotype cluster. The major clinical risk factors were diabetes mellitus in 31% (43) of cases, followed by incomplete treatment of latent TB infection (LTBI) in 11% (16). Major life-style risk factors included any substance use in 24% (34), non-injecting drug use in 18% (26), and excess alcohol use in 13% (18) of cases. Conclusion This study highlights epidemiologic differences between individuals with TB in Detroit and the US. Almost 60% of the 141 Detroit TB cases were B/AA. Nationally, 10% of non-US-born individuals and 30% of US-born ones were B/AA in 2022. More than 60% of the Detroit cases were US-born. This is in stark contrast to the U.S., where 37% of cases in 2022 were US-born. A significant number of Detroiters belonged to a genotype cluster, indicating continued transmission of TB. Alcohol and drug use were major lifestyle risk factors, suggesting increased contact in shared venues contributing to transmission of TB. Knowing these local risk factors for TB should lead to earlier detection and treatment of TB and LTBI and eliminate opportunities for transmission. Disclosures All Authors: No reported disclosures

Challenges and opportunities for transmission in the 2μm waveband

Challenges and opportunities for transmission in the 2μm waveband

Efficient Node Insertion Algorithm for Connectivity-Based Multipolling MAC Protocol in Wi-Fi Sensor Networks

Since low-power Wi-Fi sensors are connected to the Internet, effective radio spectrum use is crucial for developing an efficient Medium Access Control (MAC) protocol for Wi-Fi sensor networks. A connectivity-based multipolling mechanism was employed for Access Points to grant uplink transmission opportunities to Wi-Fi nodes with a reduced number of multipolling frame transmissions. The existing connectivity-based multipolling mechanism in IEEE 802.11 wireless LANs with many nodes may require excessive time to derive the optimal number of serially connected sequences due to the backtracking algorithm based on the Traveling Salesman Problem model. This limitation hinders the real-time implementation of the connectivity-based multipolling mechanism in Wi-Fi sensor networks. In this study, an efficient node insertion algorithm is proposed, by which the number of derived serially connected multipolling sequences that cover nodes in Wi-Fi sensor networks converges to only one as the number of Wi-Fi sensors increases in Wi-Fi sensor networks. As verified by simulation experiments for Wi-Fi sensor networks, the proposed node insertion algorithm produces a near-optimal number of multipolling sequences that cover the nodes in Wi-Fi sensor networks. This study proposes a node insertion algorithm for the real-time implementation of the connectivity-based multipolling mechanism in MAC protocol for Wi-Fi sensor networks.

An Efficient NB-IoT Compatible GF-NOMA PHY Mechanism for mMTC

The third generation partnership project (3GPP) has proposed the narrowband Internet of things (NB-IoT) standard for serving IoT users. Improvements to the NB-IoT standard are being considered to efficiently support massive machine-type communication (mMTC) IoT applications. Subsequent releases of the NB-IoT standard envision to support mMTC using different access mechanisms. In this work, a grant-free (GF) non-orthogonal multiple access (NOMA) system compatible with the current NB-IoT standard is proposed, where the resources are divided into transmission opportunities (TOs). The TOs are further divided into multiple groups based on the repetitions adopted by the users in the system. Physical (PHY) layer procedures for preamble transmission/detection, channel estimation, data transmission/decoding, and acknowledgment (ACK) transmission/reception are described in detail for the proposed GF-NOMA system. Specifically, the preamble sequences are also used as spreading sequences for data transmission and three types of sequences -Zadoff-Chu, random Gaussian and Golay sequences are explored. Results are presented for per-user success probability, latency and energy consumption considering two NB-IoT compatible settings along with repetitions and retransmissions. It is demonstrated that the proposed GF-NOMA scheme meets the mMTC requirement recommended by the 3GPP with more than 99% per-user success probability and with the energy consumption reduced by at least 80% compared to NB-IoT, while being readily compatible with the current NB-IoT standard.

Sequential Offloading for Distributed DNN Computation in Multiuser MEC Systems

This paper studies a sequential task offloading problem for a multiuser mobile edge computing (MEC) system. While most of the existing works consider static one-shot offloading optimization with fixed wireless channel conditions and fixed computational tasks, we consider a dynamic optimization approach, which embraces wireless channel fluctuations and random deep neural network (DNN) task arrivals over an infinite horizon. Specifically, we introduce a local CPU workload queue (WD-QSI) and an MEC server workload queue (MEC-QSI) to model the dynamic workload of DNN tasks at each WD and the MEC server, respectively. The transmit power and the partitioning of the local DNN task at each WD are dynamically determined based on the instantaneous channel conditions (to capture the transmission opportunities) and the instantaneous WD-QSI and MEC-QSI (to capture the dynamic urgency of the tasks) to minimize the average latency of the DNN tasks. The joint optimization can be formulated as an ergodic Markov decision process (MDP), in which the optimality condition is characterized by a centralized Bellman equation. However, the brute force solution of the MDP is not viable due to the curse of dimensionality as well as the requirement for knowledge of the global state information. To overcome these issues, we first decompose the MDP into multiple lower dimensional sub-MDPs, each of which can be associated with a WD or the MEC server. Next, we further develop a parametric online Q-learning algorithm, so that each sub-MDP is solved locally at its associated WD or the MEC server. The proposed solution is completely decentralized in the sense that the transmit power for sequential offloading and the DNN task partitioning can be determined based on the local channel state information (CSI) and the local WD-QSI at the WD only. Additionally, no prior knowledge of the distribution of the DNN task arrivals or the channel statistics will be needed for the MEC server. The proposed solution can achieve the superb performance over various state-of-the-art baselines.

Energy-Aware Mode Selection for D2D Resource Allocation in 5G Networks

This paper proposes an energy-aware mode-selection mechanism for device-to-device (D2D) resource allocation in the coexisting 5G network environment of D2D users and traditional cellular users by taking into consideration the mechanisms of mode selection, transmit power, and spectrum resource allocation simultaneously. In the proposed approach, all spectrum resources are fully shared by traditional cellular users and D2D users. We first determine the communication mode of all users after considering the transmission opportunity of traditional cellular users and analyzing the interference degree of different D2D communication modes. Next, we divide all users into three tiers according to the distances between users and the base station to solve the interference problem generated by excessing transmit power in uplink transmission. Afterward, based on the different communication modes, corresponding spectrum resource allocation mechanisms using the Hungarian algorithm are developed. We simulate a single cell environment using Python language and perform several simulations for different pairs of traditional cellular users and D2D users. The simulation results reveal that the proposed approach outperforms the proposed approach by Hou et al. in system throughput. With power control, the energy efficiency of the proposed approach could be enhanced by 20%.

Bacterial Communities of the Internal Reproductive and Digestive Tracts of Virgin and Mated Tuta absoluta.

Microorganisms can affect host reproduction, defense, and immunity through sexual or opportunistic transmission; however, there are few studies on insect reproductive organs and intestinal bacterial communities and their effects on mating. Tuta absoluta is a worldwide quarantine pest that seriously threatens the production of Solanaceae crops, and the microbial community within tomato leafminers remains unclear. In this study, 16s rRNA sequencing was used to analyze bacterial communities related to the reproductive organs and intestinal tracts of tomato leafminers (the sample accession numbers are from CNS0856533 to CNS0856577). Different bacterial communities were found in the reproductive organs and intestinal tracts of females and males. Community ecological analysis revealed three potential signs of bacterial sexual transmission: (1) Mating increased the similarity between male and female sex organs and intestinal communities. (2) The bacteria carried by mated individuals were found in unmated individuals of the opposite sex but not in unmated individuals of the same sex. (3) The bacteria carried by unmated individuals were lost after mating. In addition, the abundances of bacterial communities carried by eggs were significantly higher than those of adult worms. Our results confirm that mating leads to the transfer of bacterial communities in the reproductive organs and gut of tomato leafminers, and suggest that this community strongly influences the reproductive process.

Throughput‐delay tradeoff for opportunistic spectrum access in cognitive radio networks

AbstractThe internet of things accelerates the wireless connections of massive devices to provide all kinds of new services, and thus intensifies the spectrum scarcity and access delay. Cognitive radio (CR) technology brings a solution for the issue. As a typical CR scheme, opportunistic spectrum access (OSA) has been addressed widely in the past decade. However, the tradeoff between two key indexes, the throughput of cognitive radio network (CRN) and the delay of secondary user (SU), is rarely mentioned so far, which ignites the authors’ work in this paper. Taking into account a channel handoff (CH) based multi‐channel OSA scenario, the authors first analyze the opportunistic transmission performance of SU, and model the throughput of CRN as well as the handoff delay of SU. Then, the authors build up a delay‐constraint throughput optimization problem, and thus formulate the throughput‐delay tradeoff for OSA. Finally, the optimal traffic rates of SU for a good throughput‐delay tradeoff are derived according to maximizing the throughput of CRN. Theoretical and simulated results show that to enhance the throughput and to reduce the delay do not conflict always. By well adjusting the traffic rates of SU according to the traffic rates of primary user, the throughput of CRN can be improved while the handoff delay can be kept under a given level.

FDOE: Exploit Concurrent Communication Opportunities in Full-Duplex Wireless Mesh Networks

In recent years, full-duplex communications in a single frequency channel have become a practical technology. However, existing full-duplex medium access control (MAC) protocols can hardly take full advantages of full-duplex transmission opportunities, because they are not capable of adding one more half-duplex link on an on-going half-duplex link to form a full-duplex link. Besides, the exposed node and hidden node issues in multi-hop wireless networks limit flexible establishment of full-duplex links. Such limitations waste full-duplex transmission opportunities, and thus degrade network performance. In this paper, an efficient full-duplex link establishment protocol called full-duplex opportunity exploitation (FDOE) is developed to exploit full-duplex transmission opportunities in a wireless mesh network. FDOE leverages rateless coding and pseudo-noise (PN) sequences to establish a full-duplex link whenever a full-duplex transmission opportunity is available. Such a distinct feature leads to significant improvement of network performance. FDOE is evaluated through theoretical analysis and extensive simulations. Performance results show that FDOE exploits full-duplex transmission opportunities efficiently in wireless mesh networks, and thus significantly outperforms existing MAC protocols.