Inter-domain mobility with LISP-MN:a performance comparison with MIPv6

In this work, we aim to evaluate Locator Identifier Separation Protocol-Mobile Node (LISP-MN) performance in an inter-domain mobility scenario for both multi-interface and single interface MN with focus on throughput, handover delay, service disruption time and packet loss. To serve as the benchmark for performance, we compare LISP-MN with the IETF standardised MIPv6. We implement the 2 protocols on a laboratory testbed comprising all the nodes necessary for their operation. For multi-interface MNs, LISP-MN shows a better response in soft handover scenarios in terms of throughput and packet loss. MIPv6 on the other hand shows shorter handover delay with lower service disruption time in a hard handover scenario. Both protocols demonstrate poor performance for a single interface MN due to the long handover delay experienced. Although LISP-MN’s handover control messages doubled that of MIPv6, our experiments show that it takes a similar time as MIPv6 to complete the handover message exchange

An ILNP-based solution for future heterogeneous wireless networks

Utilization of the different wireless interfaces (Cellular, Wi-Fi and WiMAX) that come with many of the Mobile Nodes today is central to improving Quality of Experience and Quality of Service in future networks. Although the interfaces are of different technologies as are the access links, the core/backbone networks are now based on IP infrastructure. Efforts to simplify network handover between these technologies – termed vertical handover (VHO) – have not been successful with IP due its mechanism for managing nodes’ identity and location. Researchers have defined and implemented some solutions that proposed the separation of identity of a Mobile Node from its location, and among those proposals is the Identifier Locator Network Protocol (ILNP). In this work, we propose a Linux-based implementation of the ILNPv6 protocol – an instance of the ILNP that is compatible with IPv6 – on laboratory testbed. We also proposed an Information Server managing a defined geographical location we called AREA, to augment some of the shortfalls that we observed with ILNP. We believe that this combination provides the necessary ground for achieving seamless VHO in heterogeneous wireless environments of the future

Towards zero packet loss with LISP Mobile Node

Host mobility protocols such as Locator-Identifier Separation Protocol Mobile Node (LISP-MN) are known to experience packet loss at the point of handover. For the duration of the handover, packets sent to the MN via the old access link are dropped by the router since it has no way of knowing where the device has moved to. This affects the performance of transport layer protocols of the TCP/IP stack, which results in degradation of network performance. Buffering these packets close to the MN's new location and forwarding them to the MN on handover completion is one way of improving the overall performance of the mobility protocol. Hence, we introduce a novel network node, loc-server, to buffer these packets in order to mitigate the packet loss and reduce the service disruption time (SDT) experienced by MNs during handovers. Using a laboratory testbed implementation, LISP-MN with loc-server support shows significant reduction in packet loss and reduced SDT in comparison to vanilla LISP-MN. Similarly, performance analysis of DASH video player also shows the new architecture helps in improving the average video quality downloaded by the MN and reduces the player's instability

Experimental evaluation of the impact of mobility management protocols on HTTP adaptive streaming

Video content is increasingly being consumed on the move using mobile devices such as smartphones and tablets. In order to deal with the challenges of heterogeneity of network access technologies and fluctuating resources, which are inherent features of mobile communication, HTTP adaptive streaming (HAS) is becoming the default technology for online video streaming. However, little research has been carried out to better understand the impact of handover schemes of the various mobility management protocols on the video quality of HAS. In this study, the authors present a comprehensive experimental measurement of the impact of handover on three representative HAS players. First, they implement three existing mobility management protocols, MIPv6, LISP-MN and PMIPv6, on a network testbed. Using the fluid flow mobility model, the impact of frequent handover on the average video quality, the bandwidth utilisation and stability of the players was investigated. Their results show a degradation of all the observed parameters in all the reviewed players

Toward N-nitrosamines free water: Formation, prevention, and removal

This study elucidates the recent trends in the formation, prevention, and removal of N-nitrosamines such as Nnitrosodimethylamine(NDMA) from wastewater or drinking water. Reports are rife on the occurrence of NDMA in areas such as amine degradation during postcombustion CO2 capture (PCC), chlorinated/chloraminated and ozonated drinking water, smoked or cooked foods personal care, tobacco and pharmaceutical products. The major routes responsible for the formation of NDMA in portable waters include chlorination/ chloramination and ozonation. The major NDMA precursors are secondary, tertiary, and quaternary amines such as dimethylamine, diethanolamine, and triethanolamine. Due to the environmental and public health concerns posed by this contaminant, a proactive approach is necessary towards suppressing their occurrence, as well as their removal. Consequently, this study critically reviewed the formation, prevention, and removal of N-nitrosamines. The study discussed NDMA prevention techniques, such as physical adsorption, preoxidation, and biological activated carbon. The removal techniques discussed here include physicochemical (such as combined adsorption and microwave irradiation and UV photolysis), bioremediation, catalytic reduction, and dope technology. Irrespective of the effectiveness and seemingly economic viability of some of these technologies, preventing the occurrence of NDMA right from the outset is more potent because the treatments consume more energy

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

An improved LISP mobile node architecture

The increased use of mobile devices has prompted the need for efficient mobility management protocols to ensure continuity of communication sessions as users switch connection between available wireless access networks. Locator Identifier Separation Protocol Mobile Node (LISP-MN) was designed to enable such efficient mobility of nodes on the Internet. The protocol enables mobility by ensuring that the IP address used for creating data session is maintained throughout the lifetime of the communication session and the location of the mobile node (MN) is updated as the device moves. While session continuity is achieved during handover, we observed that LISP-MN records loss of packets in transit, long service disruption time, throughput degradation and increased rate of TCP retransmission as an MN conducts a handover from one access link to another. To mitigate the poor handover performance, we introduced a novel network node into the LISP-MN architecture, a loc-server, that buffers the packets sent to an MN during handover and forwards to the device upon completion of the movement process. We analysed both qualitative features and quantitative measurements of vanilla LISP-MN against LISP-MN with loc-server support. Results show that the improved architecture significantly improved the performance of LISP-MN in all the investigated parameters

Rumen fermentation characteristics of west African dwarf goats fed enzyme supplemented total mixed ration in the dry season

The study was conducted to investigate the effect of exogenous enzyme additive on rumen environment parameters of West African Dwarf (WAD) goats fed total mixed ration (TMR) for a period of 70 days. Four experimental diets were formulated with enzyme included at 0.0, 0.2, 0.4 and 0.6 g/kg dry matter to constitute treatments 1,2, 3 and 4 respectively. Sixteen growing WAD goats were subjected to the four dietary treatments in a completely randomized design. Rumen fluid was collected from the goats before the commencement and at the end of the feeding trial. Data were collected on rumen pH, ammonia nitrogen, volatile fatty acids (VFAs) production and microbial population. Enzyme additive significantly (p<0.05) affect the total VFAs, propionic acid and butyric acid production with the highest values (86.23, 26.17, 14.87 Mm/100ml) for the three respectively obtained at T4(0.6g/kg). The bacteria count was significantly highest (5.20 × 106cfu/ml) at T3 although not statistically different from what was obtained at T4. A total of 5 bacteria (Bacteroides, Clostridium, Fusobacterium, Streptococcus and Peptococcus spp.), 1 fungus (Aspergillus spp.) and 2 protozoa (Holotrich spp. and Trichuris spp.) species were isolated from the rumen at the end of the study. It was therefore concluded that exogenous enzyme containing cellulase, xylanase and beta glucanase can be included in a TMR for WAD goats at 0.4g/kg for increased bacteria count and total VFAs production.Keywords: Exogenous enzyme, Total mixed ration, Goats, Rumen fluid, Microbial populatio

HIV status disclosure to male partners among rural Nigerian women along the prevention of mother-to-child transmission of HIV cascade: a mixed methods study

Abstract Background HIV status disclosure to male partners is important for optimal outcomes in the prevention of mother-to-child transmission of HIV (PMTCT). Depending on timing of HIV diagnosis or pregnancy status, readiness to disclose and disclosure rates may differ among HIV-positive women. We sought to determine rates, patterns, and experiences of disclosure among Nigerian women along the PMTCT cascade. Methods HIV-positive women in rural North-Central Nigeria were purposively recruited according to their PMTCT cascade status: pregnant-newly HIV-diagnosed, pregnant-in care, postpartum, and lost-to-follow-up (LTFU). Participants were surveyed to determine rates of disclosure to male partners and others; in-depth interviews evaluated disclosure patterns and experiences. Tests of association were applied to quantitative data. Qualitative data were manually analysed by theme and content using the constant comparative method in a Grounded Theory approach. Results We interviewed 100 women; 69% were 21–30 years old, and 86% were married. There were 25, 26, 28 and 21 women in the newly-diagnosed, in-care, postpartum, and LTFU groups, respectively. Approximately 81% of all participants reported disclosing to anyone; however, family members were typically disclosed to first. Ultimately, more women had disclosed to male partners (85%) than to family members (55%). Rates of disclosure to anyone varied between groups: newly-diagnosed and LTFU women had the lowest (56%) and highest (100%) rates, respectively (p = 0.001). However, family (p = 0.402) and male partner (p = 0.218) disclosure rates were similar between cascade groups. Across all cascade groups, fear of divorce and intimate partner violence deterred women from disclosing to male partners. However, participants reported that with assistance from healthcare workers, disclosure and post-disclosure experiences were mostly positive. Conclusion In our study cohort, although disclosure to male partners was overall higher, family members appeared more approachable for initial disclosure. Across cascade groups, male partners were ultimately disclosed to at rates > 75%, with no significant inter-group differences. Fear appears to be a major reason for non-disclosure or delayed disclosure by women to male partners. Augmentation of healthcare workers’ skills and involvement can mediate gender power differentials, minimize fear and shorten time to male partner disclosure among women living with HIV, regardless of their PMTCT cascade status. Trial registration Clinicaltrials.gov registration number NCT 01936753, September 3, 2013 (retrospectively registered)

Correlates of facility delivery for rural HIV-positive pregnant women enrolled in the MoMent Nigeria prospective cohort study

Abstract Background Low rates of maternal healthcare service utilization, including facility delivery, may impede progress in the prevention of mother-to-child transmission of HIV (PMTCT) and in reducing maternal and infant mortality. The MoMent (Mother Mentor) study investigated the impact of structured peer support on early infant diagnosis presentation and postpartum maternal retention in PMTCT care in rural Nigeria. This paper describes baseline characteristics and correlates of facility delivery among MoMent study participants. Methods HIV-positive pregnant women were recruited at 20 rural Primary Healthcare Centers matched by antenatal care clinic volume, client HIV prevalence, and PMTCT service staffing. Baseline and delivery data were collected by participant interviews and medical record abstraction. Multivariate logistic regression with generalized estimating equation analysis was used to evaluate for correlates of facility delivery including exposure to structured (closely supervised Mentor Mother, intervention) vs unstructured (routine, control) peer support. Results Of 497 women enrolled, 352 (71%) were between 21 and 30 years old, 319 (64%) were Christian, 245 (49%) had received secondary or higher education, 402 (81%) were multigravidae and 299 (60%) newly HIV-diagnosed. Delivery data was available for 445 (90%) participants, and 276 (62%) of these women delivered at a health facility. Facility delivery did not differ by type of peer support; however, it was positively associated with secondary or greater education (aOR 1.9, CI 1.1–3.2) and Christian affiliation (OR 1.4, CI 1.0–2.0) and negatively associated with primigravidity (OR 0.5; 0.3–0.9) and new HIV diagnosis (OR 0.6, CI 0.4–0.9). Conclusions Primary-level or lesser-educated HIV-infected pregnant women and those newly-diagnosed and primigravid should be prioritized for interventions to improve facility delivery rates and ultimately, healthy outcomes. Incremental gains in facility delivery from structured peer support appear limited, however the impact of duration of pre-delivery support needs further investigation. Religious influences on facility delivery and on general maternal healthcare service utilization need to be further explored. Trial Registration ClinicalTrials.gov number NCT01936753 , registered September 2013