Dtn and non-dtn routing protocols for inter-cubesat communications: A comprehensive survey

CubeSats, which are limited by size and mass, have limited functionality. These miniaturised satellites suffer from a low power budget, short radio range, low transmission speeds, and limited data storage capacity. Regardless of these limitations, CubeSats have been deployed to carry out many research missions, such as gravity mapping and the tracking of forest fires. One method of increasing their functionality and reducing their limitations is to form CubeSat networks, or swarms, where many CubeSats work together to carry out a mission. Nevertheless, the network might have intermittent connectivity and, accordingly, data communication becomes challenging in such a disjointed network where there is no contemporaneous path between source and destination due to satellites’ mobility pattern and given the limitations of range. In this survey, various inter-satellite routing protocols that are Delay Tolerant (DTN) and Non Delay Tolerant (Non-DTN) are considered. DTN routing protocols are considered for the scenarios where the network is disjointed with no contemporaneous path between a source and a destination. We qualitatively compare all of the above routing protocols to highlight the positive and negative points under different network constraints. We conclude that the performance of routing protocols used in aerospace communications is highly dependent on the evolving topology of the network over time. Additionally, the Non-DTN routing protocols will work efficiently if the network is dense enough to establish reliable links between CubeSats. Emphasis is also given to network capacity in terms of how buffer, energy, bandwidth, and contact duration influence the performance of DTN routing protocols, where, for example, flooding-based DTN protocols can provide superior performance in terms of maximizing delivery ratio and minimizing a delivery delay. However, such protocols are not suitable for CubeSat networks, as they harvest the limited resources of these tiny satellites and they are contrasted with forwarding-based DTN routing protocols, which are resource-friendly and produce minimum overheads on the cost of degraded delivery probability. From the literature, we found that quota-based DTN routing protocols can provide the necessary balance between delivery delay and overhead costs in many CubeSat missions

Biventricular implantable cardioverter-defibrillator device placement in patients with hostile tricuspid valve anatomy: two case reports and review of the literature

AIMS: Right ventricular (RV) lead placement can be contraindicated in patients after tricuspid valve (TV) surgery. Placement of the implantable cardiac-defibrillator (ICD) lead in the middle cardiac vein (MCV) can be a viable option in these patients who have an indication for biventricular (BiV) ICD. We aim to describe the case of two patients with MCV lead placement and provide a comprehensive review of patients with complex TV pathology and indications for RV lead placement. METHODS AND RESULTS: We describe the cases of two patients with TV pathology unsuitable for the standard transvenous or surgical RV lead placement and undergoing BiV ICD implantation. Their characteristics, procedure, and outcomes are summarized. The BiV ICD was successfully placed with the RV lead positioned in the MCV in both patients. The procedures had no complications and were well-tolerated. On follow-up, both patients had appropriate tachytherapy with no readmissions for heart failure or worsening of cardiac function. CONCLUSION: Right ventricular lead placement of BiV ICD in the MCV can be an excellent alternative in patients with significant TV pathology and poor surgical candidacy

The Impact of Two Proposed Strategies Based on Active Learning on Students' Achievement at the Computer and Their Social Intelligence

Active learning is a teaching method that involves students actively participating in activities, exercises, and projects within a rich and diverse educational environment. The teacher plays a role in encouraging students to take responsibility for their own education under their scientific and pedagogical supervision and motivates them to achieve ambitious educational goals that focus on developing an integrated personality for today’s students and tomorrow’s leaders. It is important to understand the impact of two proposed strategies based on active learning on the academic performance of first-class intermediate students in computer subjects and their social intelligence. The research sample was intentionally selected, consisting of 99 students. The experimental group comprised 33 students from division (B) who were taught according to the first proposed strategy, while the second experimental group, represented by division (A), and also consisted of 33 students. The control group, made up of 33 students from division (C), was taught using the usual method. Two tools have been prepared: an achievement test with 40 items and a measure of social intelligence consisting of 20 items. The research results indicated that the experimental groups, which utilized the first and second proposed strategies based on active learning, outperformed the control group. As a result, several conclusions, recommendations, and proposals were made

The non‐linear effects of energy efficiency gains on the incidence of energy poverty

Energy poverty is defined as insufficient access to modern energy resources which are relatively cleaner than the traditionally utilized ones. In this regard, the incidence of energy poverty is particularly higher in the cases of the developing countries across the globe. Accordingly, the chronic energy poverty issues in the developing countries within Sub‐Saharan Africa have become a major socioeconomic and environmental concern for the associated governments. Hence, this study aims to evaluate the effects of energy efficiency gains and shocks to other key macroeconomic factors on energy poverty in the context of selected Sub‐Saharan African nations. In this study, we measure energy poverty in terms of the lack of access to clean cooking fuels and technologies for the population of the selected Sub‐Saharan African countries. The overall findings from the common correlated effects panel regression analysis reveal that energy efficiency gains initially aggravate the energy poverty situation but improve it later on; consequently, a U‐shaped relationship between energy efficiency and access to clean cooking fuels and technologies is evidenced. Besides, the predicted threshold levels of energy efficiency are observed to be higher than the average energy efficiency level of the Sub‐Saharan African nations. Moreover, the results also portray that economic growth, carbon dioxide emissions, foreign direct investment inflows, and international trade are effective in reducing energy poverty. Conversely, financial development is witnessed to be ineffective in influencing the incidence of energy poverty in this region

Clinical Outcome of Breast Cancer Occurring after Treatment for Hodgkin's Lymphoma: Case-Control Analysis

Background: To evaluate diagnosis, management and outcome of breast cancer (BC) occurring after irradiation for Hodgkin's lymphoma (HL). Methods: 39 cases of BC in 28 HL survivors were retrospectively reviewed. 21 patients were included in a case-control analysis. Results: The median age at diagnosis of HL and BC was 25.3 and 45.3 years, respectively. The median interval to develop BC was 16.1 years. Eleven women (39.2%) had bilateral disease. Mode of detection of the index breast cancers was by mammographic screening in 17 patients (60.7%), palpable lump in 8 patients (28.6%), clinical examination in two patients (7.1%), and unknown in one patient (3.6%). Case-control analysis showed that histological features and prognosis of BC after HL were similar to those of primary BC, however, for BC after HL, mastectomy was the predominant surgery (P = .001) and adjuvant radiotherapy and anthracycline-based chemotherapy were less frequently used as compared to primary BC (P < .001 and .003, respectively). Conclusion: The previous history of HL does not appear to be a poor prognostic factor for BC occurring thereafter

Clinical outcome of breast cancer occurring after treatment for Hodgkin's lymphoma: case-control analysis

<p>Abstract</p> <p>Background</p> <p>To evaluate diagnosis, management and outcome of breast cancer (BC) occurring after irradiation for Hodgkin's lymphoma (HL).</p> <p>Methods</p> <p>39 cases of BC in 28 HL survivors were retrospectively reviewed. 21 patients were included in a case-control analysis.</p> <p>Results</p> <p>The median age at diagnosis of HL and BC was 25.3 and 45.3 years, respectively. The median interval to develop BC was 16.1 years. Eleven women (39.2%) had bilateral disease. Mode of detection of the index breast cancers was by mammographic screening in 17 patients (60.7%), palpable lump in 8 patients (28.6%), clinical examination in two patients (7.1%), and unknown in one patient (3.6%). Case-control analysis showed that histological features and prognosis of BC after HL were similar to those of primary BC, however, for BC after HL, mastectomy was the predominant surgery (<it>P </it>= .001) and adjuvant radiotherapy and anthracycline-based chemotherapy were less frequently used as compared to primary BC (<it>P </it>< .001 and .003, respectively).</p> <p>Conclusion</p> <p>The previous history of HL does not appear to be a poor prognostic factor for BC occurring thereafter.</p

AWARENESS ON ENERGY MANAGEMENT IN RESIDENTIAL BUILDINGS: A CASE STUDY IN KAJANG AND PUTRAJAYA

This paper presents a case study on a survey and measurement being carried out for the purpose of determining residential electric power consumption and awareness toward smart energy management system in the areas of Putrajaya and Kajang, Malaysia. Questionnaires were developed with 37 questions grouped in 5 different sections related to home appliance information. Data was collected from a sample size of 384 respondents with confidence level of 95%. The accuracy of the percentage energy usage data were analysed by applying the SPSS software. Actual residential electric power consumption was measured by using a power quality analyser to determine the total power consumption at weekday and weekend and power consumption of each electrical appliance. The measurement results showed that the average energy consumption is 25.8 kWh/day during weekend and 21.9 kWh/day during weekdays with 11.5 kWh/day for the air conditioner only. The survey results revealed that 89.06% of the respondents expressed awareness toward household power consumption and that they are willing to install home automation system to reducing their electricity bill

Smart plug prototype for monitoring electrical appliances in home energy management system

Recently, the technology of Home Energy Management System (HEMS) has expanded for the purpose of reducing energy consumption. This paper presents the development of a smart plug with a wireless Zigbee sensor for measuring power consumption of electrical appliances in the HEMS. Experiments were carried out to evaluate the power consumption of a wireless sensor node in a smart plug using only Zigbee as a microcontroller. Experimental results showed that the smart plug using Zigbee is capable of processing and analyzing the analogue sensor signal with lower power consumption. In addition, the data obtained from the wireless sensor is more accurate and smoother as compared with the data obtained from the oscilloscope. The proposed smart plug has the characteristics of simple design, low cost, low power consumption and easy to control electrical home appliances by switching on/off from the HEMS controller

Incidence and clinical outcomes of nosocomial infections in patients presenting with STEMI complicated by cardiogenic shock in the United States

OBJECTIVES: This study addresses the incidence, trends, and impact of nosocomial infections (NI) on the outcomes of patients admitted with ST-segment elevation myocardial infarction (STEMI) and cardiogenic shock (STEMI-CS) using the United States National Inpatient Sample (NIS) database. METHODS: We analyzed data from 105,184 STEMI-CS patients using the NIS database from the years 2005-2014. NI was defined as infections of more than or equal to three days, comprising of central line-associated bloodstream infection (CLABSI), urinary tract infection (UTI), hospital-acquired pneumonia (HAP), Clostridium difficile infection (CDI), bacteremia, and skin related infections. Outcomes of the impact of NI on STEMI-CS included in-hospital mortality, length of hospital stay (LOS) and costs. Significant associations of NI in patients admitted with STEMI-CS were also identified. RESULTS: Overall, 19.1% (20,137) of patients admitted with STEMI-CS developed NI. Trends of NI have decreased from 2005-2014. The most common NI were UTI (9.2%), followed by HAP (6.8%), CLABSI (1.5%), bacteremia (1.5%), skin related infections (1.5%), and CDI (1.3%). The strongest association of developing a NI was increasing LOS (7-9 days; OR: 1.99; 95% CI: 1.75-2.26; \u3e9 days; OR: 4.51; 95% CI: 4.04-5.04 compared to 4-6 days as reference). Increased mortality risk among patients with NI was significant, especially those with sepsis-associated NI compared to those without sepsis (OR: 2.95; 95% CI: 2.72-3.20). Patients with NI were found to be associated with significantly longer LOS and higher costs, irrespective of percutaneous mechanical circulatory support placement. CONCLUSIONS: NI were common among patients with STEMI-CS. Those who developed NI were at a greater risk of in-hospital mortality, increased LOS and costs