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This work uses NS3 simulation to study the effect of mobility speed on the performance of three handover algorithms in Long Term Evolution (LTE) Networks. A realistic multi-cell LTE network was set up using NS3 simulation software. Mobility models were used to vary the location of the User Equipment (UE), hence triggering handover events across the network. The performance was measured using Signal Interference Noise Ratio (SINR) and number of completed handovers. Result revealed that at a speed between the ranges of 0 - 3 km/h, the Integrative algorithm performed best while at 4 - 60km/h, the performance of the A3RSRP algorithm was the best with an average value of 95dB. Also, at an increased speed within the range of 60 - 120 km/h, the Integrative algorithm had a slightly better performance than the A3RSRP. However, at a speed above 120 km/h, the integrative algorithm performed best with an SINR of 120dB. In terms of completed handovers, the Integrative algorithm had the least number of completed handovers throughout the entire range of considered speeds. Thus, we establish that mobility speed has a significant effect on the performance of handover algorithms. [ABSTRACT FROM AUTHOR]

Frequency Rate (FRR), Fatality Rate (FAR) and Severity Rate (SR) are common parameters used in communicating the research output of occupational accidental injuries. These parameters have been used to provide a model for classifying an occupational work activity into five level/degrees of safety ranging between Very Safe and Highly Unsafe. With a work activity defined as x: x ≤ 0.01, x ≤ 0.003 or x ≤ 0.03 indicates Very Safe Level while x > 0.04, x > 0.015 or x>0.11 indicates Highly Unsafe Level according to FRR, SR and FAR respectively. A case study is provided from an existing work to experiment the application of the model. [ABSTRACT FROM AUTHOR]

In this research effort, ballistic performance of a quenched and tempered steel was investigated. Low alloy steel was selected where austenization, quenching and finally tempering at 600°C were applied to it. Thereafter, the heat-treated steel was shot with armour piercing 7.62 mm calibre and the occurrence of failure, after the interaction between the projectile and the steel, was investigated. The shot was performed at zero degree (0°) obliquity with a projectile velocity of 830m/s. After the shot, microstructural and fractographical examinations were carried out on the sample taken from the perforated region using scanning electron microscopes to determine the matrix phase and secondary phases. It was observed that the steels had tempered martensitic-bainitic matrices after heat treatments; a crater was formed on the front side of the steel; deformed and transformed adiabatic shear bands had an effect on the crack formation and propagation in the matrix; and perforation mode of the steels was typical petalling. [ABSTRACT FROM AUTHOR]

The expected electricity demand level of unelectrified communities is one of the variables that guide rural electrification planners and electricity distribution utilities in making the choice of extending electricity grid to such communities and in using appropriate sizes of distribution assets such as transformers. This study presents the result of a survey to determine the level of household electricity demand in two villages in South-West Nigeria. The electricity demand is determined using a bottom-up approach which traces the household electricity demand through the purpose of use, the type and number of electrical appliance, and the duration of use. The result shows that most respondents will use bulbs for up to 8 hours per day but those who own refrigerators will power it for over 16 hours per day. The level of electricity consumption in the households sampled range from 0.38–20.56 kWh/day. Policy implications are discussed.

Introduction: Surgical techniques for sellar reconstruction include no reconstruction, use of synthetic materials, autologous grafts, and/or vascularized flaps. The aim of this study was to conduct a multi-center study comparing the efficacy and postoperative morbidity associated with different sellar reconstruction techniques., Methods: A retrospective chart review of patients who underwent endoscopic transsphenoidal surgery for pituitary tumors from five participating sites between January 2021 and March 2023 was performed. The variables included demographics, tumor characteristics, reconstruction technique, postoperative cerebrospinal fluid leak (CSF) leak, and 22-item Sino-Nasal Outcome Test (SNOT-22) scores. Comparisons of postoperative complications, SNOT-22 scores, and duration of surgery by type of onlay reconstruction were evaluated using Fisher's exact test, analysis of variance, and Kruskal‒Wallis test., Results: Five hundred and one patients were identified. The median tumor size was 2.1 cm, and 64% were non-functioning. Intraoperative CSF leak was identified in 38% of patients. A total of 89% of patients underwent onlay reconstruction: 49% were reconstructed with mucosal grafts, 35% with nasoseptal flaps, and 5% with other onlay techniques. Nasoseptal flaps were utilized more frequently in the setting of giant pituitary adenomas (>3 cm), medial cavernous sinus wall resection, and high-flow intraoperative CSF leaks. Cases who utilized mucosal grafts had an overall shorter operating time (median: 183 min vs. 240 min; p < 0.001). Five postoperative CSF leaks were identified, and therefore, statistical analysis could not be performed for this complication., Conclusion: The effectiveness and morbidity of different sellar reconstruction techniques are comparable. Vascularized flaps were utilized more frequently in the setting of larger tumors and high-flow intraoperative CSF leaks., (© 2024 ARS‐AAOA, LLC.)

Key Points: Virtual reality (VR) and Fitbit devices are well tolerated by patients after skull base surgery. Postoperative recovery protocols may benefit from incorporation of these devices. However, challenges including patient compliance may impact optimal device utilization., (© 2024 ARS‐AAOA, LLC.)

Background: With modern treatment paradigms, olfactory neuroblastoma (ONB) has favorable overall survival (OS); however, the incidence of recurrence remains high. The primary aims of this study were to delineate the prognosis of recurrence of ONB and explore how recurrence subsites are associated with OS, disease-specific survival (DSS), and further recurrence., Methods: A retrospective chart review of ONB cases from nine academic centers between 2005 and 2021 was completed. Tumor characteristics, recurrence subsites, timelines to recurrence, additional recurrences, and survival estimates were determined using descriptive and time-to-event analyses., Results: A final cohort of 233 patients was identified, with 70 (30.0%) patients recurring within 50.4 (standard deviation ±40.9) months of diagnosis on average, consisting of local (50%), neck (36%), intracranial (9%), and distant (6%) recurrence. Compared with subjects without recurrence, patients with recurrence had significantly different primary American Joint Committee on Cancer T stage (p < 0.001), overall stage (p < 0.001), and modified Kadish scores (p < 0.001). Histopathology identified that dural involvement and positive margins were significantly greater in recurrent cases. First recurrence was significantly associated with worse 5-year DSS (hazard ratio = 5.62; p = 0.003), and subjects with neck or local recurrence had a significantly better DSS compared to intracranial or distant recurrence., Conclusions: Recurrent cases of ONB have significantly different stages and preoperative imaging factors. Patients with local or neck recurrence, however, have better DSS than those with intracranial or distant recurrence, independent of initial tumor stage or Hyams grade. Identifying specific factors that confer an increased risk of recurrence and DSS is important for patient counseling in addition to surveillance planning., (© 2024 ARS‐AAOA, LLC.)

Purpose: The incidence of ageusia and dysgeusia after endoscopic endonasal (EEA) resection of olfactory groove meningioma (OGM) is not well established despite recognized impairment in olfactory function., Methods: We retrospectively administered a validated taste and smell survey to patients undergoing EEA for resection of OGM at two institutions. Demographics and clinical characteristics were collected and survey responses were analyzed., Results: Twelve patients completed the survey. The median time from surgery was 24 months. The average total complaint score was 5.5 out of 16 [0-13]. All patients reported a change in sense of smell while only 42 % reported a change in sense of taste. Taste changes did not consistently associate with laterality or size of the neoplasm. Significant heterogeneity existed when rating severity of symptoms., Conclusions: To our knowledge this is the first case series examining taste changes after EEA resection of OGM. Despite universal olfactory dysfunction, only a minority of patients reported a change in their sense of taste. Our findings may improve patient counseling and expectations after surgery., Competing Interests: Declaration of competing interest Authors report no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Historically, comprehensive surgical resection for olfactory neuroblastoma has included the bilateral olfactory epithelium, cribriform plate, overlying dura, olfactory bulbs and tracts. This results in postoperative anosmia that may significantly impact a patient's quality of life without definitive added benefit in survival. The prevalence of occult intracranial disease is low, especially for Hyams grade I and II tumors. A unilateral approach sparing the contralateral cribriform plate and olfactory system can be considered for select cases of early stage, low-grade tumors when the disease does not cross midline to involve the contralateral olfactory cleft or septal mucosa and when midline dural margins can be cleared with frozen pathology. Approximately half of patients who undergo unilateral resection may have residual olfaction even with adjuvant unilateral radiation. Early data suggest favorable disease-free survival and overall survival for patients who underwent the unilateral approach; however, larger sample studies are needed to confirm comparability to bilateral resections regarding oncologic outcomes., (© 2024 ARS‐AAOA, LLC.)

Background: Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field., Methods: In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication., Results: The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention., Conclusion: As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses., (© 2023 The Authors. International Forum of Allergy & Rhinology published by Wiley Periodicals LLC on behalf of American Academy of Otolaryngic Allergy and American Rhinologic Society.)

This study explores the potential of water financialisation and entrepreneurship in sub-Saharan Africa (SSA) to supplant the traditional responsibility of national, state, and local governments in providing public water supply, aligning with SDG Goals. Despite its typical association with the global north, a shifting landscape reveals emerging financial actors and multinational companies playing a more prominent role, prompting governance and accountability inquiries. Given the dearth of investment and persisting challenges in SSA's water infrastructure, the burgeoning involvement of financial actors and capital management entities in the water cycle seems inevitable. However, this trend raises concerns about exacerbating global water stress. Through qualitative methods, the study engaged 50 SSA participants via open-ended questionnaires, analysed using thematic analysis. The findings underscore a nuanced perspective. While acknowledging the potential of water financialisation and entrepreneurship to drive essential investment in SSA's water sector, the research emphasizes the irreplaceable role of government in policy execution and safeguarding citizens' well-being. Government intervention remains crucial to ensuring equitable water access and sustainability. Additionally, the analysis suggests that overemphasizing water financialisation could divert attention from critical infrastructural and technological advancements needed in SSA's water sector. This underscores the necessity of a balanced and comprehensive approach to address the multifaceted challenges surrounding water availability, governance, and sustainability in the region., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

Importance: Current olfactory neuroblastoma (ONB) staging systems inadequately delineate locally advanced tumors, do not incorporate tumor grade, and poorly estimate survival and recurrence., Objective: The primary aims of this study were to (1) examine the clinical covariates associated with survival and recurrence of ONB in a modern-era multicenter cohort and (2) incorporate Hyams tumor grade into existing staging systems to assess its ability to estimate survival and recurrence., Design, Setting, and Participants: This retrospective, multicenter, case-control study included patients with ONB who underwent treatment between January 1, 2005, and December 31, 2021, at 9 North American academic medical centers., Intervention: Standard-of-care ONB treatment., Main Outcome and Measures: The main outcomes were overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) as C statistics for model prediction., Results: A total of 256 patients with ONB (mean [SD] age, 52.0 [15.6] years; 115 female [44.9%]; 141 male [55.1%]) were included. The 5-year rate for OS was 83.5% (95% CI, 78.3%-89.1%); for DFS, 70.8% (95% CI, 64.3%-78.0%); and for DSS, 94.1% (95% CI, 90.5%-97.8%). On multivariable analysis, age, American Joint Committee on Cancer (AJCC) stage, involvement of bilateral maxillary sinuses, and positive margins were associated with OS. Only AJCC stage was associated with DFS. Only N stage was associated with DSS. When assessing the ability of staging systems to estimate OS, the best-performing model was the novel modification of the Dulguerov system (C statistic, 0.66; 95% CI, 0.59-0.76), and the Kadish system performed most poorly (C statistic, 0.57; 95% CI, 0.50-0.63). Regarding estimation of DFS, the modified Kadish system performed most poorly (C statistic, 0.55; 95% CI, 0.51-0.66), while the novel modification of the AJCC system performed the best (C statistic, 0.70; 95% CI, 0.66-0.80). Regarding estimation of DSS, the modified Kadish system was the best-performing model (C statistic, 0.79; 95% CI, 0.70-0.94), and the unmodified Kadish performed the worst (C statistic, 0.56; 95% CI, 0.51-0.68). The ability for novel ONB staging systems to estimate disease progression across stages was also assessed. In the novel Kadish staging system, patients with stage VI disease were approximately 7 times as likely to experience disease progression as patients with stage I disease (hazard ratio [HR], 6.84; 95% CI, 1.60-29.20). Results were similar for the novel modified Kadish system (HR, 8.99; 95% CI, 1.62-49.85) and the novel Dulguerov system (HR, 6.86; 95% CI, 2.74-17.18)., Conclusions and Relevance: The study findings indicate that 5-year OS for ONB is favorable and that incorporation of Hyams grade into traditional ONB staging systems is associated with improved estimation of disease progression.

The COVID-19 pandemic unveiled the vulnerability of many African healthcare systems, amplifying inadequacies and constraints in the supply chain for medical products and technologies on the continent. Disruptions in the global supply chain due to the pandemic resulted in the continent's population of over one billion people grappling with shortages in the supply of essential medicines. The shortages and their consequences set back achievement of Sustainable Development Goals and progress towards universal health coverage. A virtual meeting of global experts in medical products and supply chain identified as urgent the need for Africa to build capacity for a self-reliant public health system. Discussants challenged the governments of African countries to turn the continent from its current import driven economy to a continent of indigenous research and development, local production, and an exporter of its medical products and innovations., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Objective: The rates of women and underrepresented racial and ethnic minority (UREM) students successfully matching into neurosurgical residency are extremely low and do not reflect the makeup of the general population. As of 2019, only 17.5% of neurosurgical residents in the United States were women, 4.95% were Black or African American, and 7.2% were Hispanic or Latinx. Earlier recruitment of UREM students will help to diversify the neurosurgical workforce. Therefore, the authors developed a virtual educational event for undergraduate students entitled "Future Leaders in Neurosurgery Symposium for Underrepresented Students'' (FLNSUS). The primary objectives of the FLNSUS were to expose attendees to 1) neurosurgeons from diverse gender, racial, and ethnic backgrounds; 2) neurosurgical research; 3) opportunities for neurosurgical mentorship; and 4) information about life as a neurosurgeon. The authors hypothesized that the FLNSUS would increase student self-confidence, provide exposure to the specialty, and reduce perceived barriers to a neurosurgical career., Methods: To measure the change in participant perceptions of neurosurgery, pre- and postsymposium surveys were administered to attendees. Of the 269 participants who completed the presymposium survey, 250 participated in the virtual event and 124 completed the postsymposium survey. Paired pre- and postsurvey responses were used for analysis, yielding a response rate of 46%. To assess the impact of participant perceptions of neurosurgery as a field, pre- and postsurvey responses to questions were compared. The change in response was analyzed, and a nonparametric sign test was performed to check for significant differences., Results: According to the sign test, applicants showed increased familiarity with the field (p < 0.001), increased confidence in their abilities to become neurosurgeons (p = 0.014), and increased exposure to neurosurgeons from diverse gender, racial, and ethnic backgrounds (p < 0.001 for all categories)., Conclusions: These results reflect a significant improvement in student perceptions of neurosurgery and suggest that symposiums like the FLNSUS may promote further diversification of the field. The authors anticipate that events promoting diversity in neurosurgery will lead to a more equitable workforce that will ultimately translate to enhanced research productivity, cultural humility, and patient-centered care in neurosurgery.

Globally, faith institutions have a range of beneficial social utility, but a lack of understanding remains regarding their role in cardiovascular health promotion, particularly for hypertension. Our objective was assessment of modalities, mechanisms and effectiveness of hypertension health promotion and education delivered through faith institutions. A result-based convergent mixed methods review was conducted with 24 databases including MEDLINE, Embase and grey literature sources searched on 30 March 2021, results independently screened by three researchers, and data extracted based on behaviour change theories. Quality assessment tools were selected by study design, from Cochrane risk of bias, ROBINS I and E, and The Joanna Briggs Institute's Qualitative Assessment and Review Instrument tools. Twenty-four publications contributed data. Faith institution roles include cardiovascular health/disease teaching with direct lifestyle linking, and teaching/ encouragement of personal psychological control. Also included were facilitation of: exercise/physical activity as part of normal lifestyle, nutrition change for cardiovascular health, cardiovascular health measurements, and opportunistic blood pressure checks. These demand relationships of trust with local leadership, contextualisation to local sociocultural realities, volitional participation but prior consent by faith / community leaders. Limited evidence for effectiveness: significant mean SBP reduction of 2.98 mmHg (95%CI -4.39 to -1.57), non-significant mean DBP increase of 0.14 mmHg (95%CI -2.74 to +3.01) three months after interventions; and significant mean SBP reduction of 0.65 mmHg (95%CI -0.91 to -0.39), non-significant mean DBP reduction of 0.53 mmHg (95%CI -1.86 to 0.80) twelve months after interventions. Body weight, waist circumference and multiple outcomes beneficially reduced for cardiovascular health: significant mean weight reduction 0.83kg (95% CI -1.19 to -0.46), and non-significant mean waist circumference reduction 1.48cm (95% CI -3.96 to +1.00). In addressing the global hypertension epidemic the cardiovascular health promotion roles of faith institutions probably hold unrealised potential. Deliberate cultural awareness, intervention contextualisation, immersive involvement of faith leaders and alignment with religious practice characterise their deployment as healthcare assets., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Sanusi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: Cerebrospinal fluid leak and pneumocephalus are rare but potentially devastating complications associated with translabyrinthine resection of cerebellopontine angle masses. Persistent pneumocephalus despite proximal eustachian tube (ET) obliteration is rare. We describe, to our knowledge, the first report of successful management of tension pneumocephalus by endoscopic endonasal ET obliteration using a novel V-loc (Covidien; Medtronic, Minneapolis, MN) suture technique., Patients: A 63-year-old man presented with altered mental status 10 months after translabyrinthine excision of a left cerebellopontine angle vestibular schwannoma measuring 2.8 × 2.9 × 3.3 cm. Computed tomography demonstrated diffuse ventriculomegaly and new pneumocephalus along the right frontal lobe, lateral ventricles, and third ventricle, and air within the left translabyrinthine resection cavity., Intervention: The patient underwent left-sided endoscopic endonasal ET obliteration using 2-0, 9-inch V-loc suture., Main Outcome Measure: Postoperatively, the patient's mental status improved with a decrease in size of the lateral and third ventricles on computed tomography., Conclusion: Endoscopic endonasal ET obliteration, a technique previously applied to recalcitrant cerebrospinal fluid leaks, is a safe and reasonable alternative to reentering the original surgical site for patients with pneumocephalus after lateral skull base surgery. Utilizing a V-loc suture for this technique instead of a traditional suture may improve procedural ease and speed., Competing Interests: The authors disclose no conflicts of interest., (Copyright © 2022, Otology & Neurotology, Inc.)

Objective: Chordomas are rare tumors of notochordal origin that are known to be locally aggressive and are often treated with surgical resection followed by adjuvant radiation therapy (RT). The accepted standard of treatment for chordomas of the mobile spine, which includes en-bloc resection with wide margins, cannot be easily applied to the chordomas of the skull base because of their proximity to critical neurovascular structures. We describe our experience with the role of surgery and adjuvant RT in the treatment of chordomas over 16 years., Methods: We performed a retrospective chart review on patients with diagnoses of clival chordoma between the years 2000 and 2015 at Northwestern Memorial Hospital. We reviewed presenting symptoms, tumor location and size, extent of resection, complications, recurrence, adjuvant treatment, and follow-up duration., Results: A total of 20 patients underwent 32 surgeries. Of the 20 initial surgeries, 80% underwent gross total resection, and 20% had subtotal resection. The mean follow-up time was 60.75 months. Mean tumor volume was 23.07 cm 3 . Most common presenting signs and symptoms were headaches (70%), cranial nerve palsies (45%), and diplopia (55%). Diplopia was defined as complaints of double vision without any objective evidence of a cranial nerve palsy. Median time to progression was 57 months, and median overall survival was 136 months. Initial tumor volume and the need for a second dose of RT either as sole or as adjuvant treatment of a recurrence had a statistically significant effect on progression-free survival (P = 0.009, 0.009). None of the factors studied had a statistically significant effect on overall survival., Conclusions: The treatment of chordomas remain challenging and requires multimodal treatment strategies spanning different specialties. Initial tumor size and need for second dose of RT for recurrence appear to play a significant role in progression-free survival. Adjuvant RT after gross total resection may play a role in improved progression-free and overall survival in patients with clival chordomas., (Copyright © 2018. Published by Elsevier Inc.)

The first half of the surfactant protein B (SP-B) gene intron 4 is a CA-repeat-rich region that contains 11 motifs. To study the role of this region on SP-B mRNA splicing, minigenes were generated by systematic removal of motifs from either the 5' or 3' end. These were transfected in CHO cells to study their splicing efficiency. The latter was determined as the ratio of completely to incompletely spliced SP-B RNA. Our results indicate that SP-B intron 4 motifs differentially affect splicing. Motifs 8 and 9 significantly enhanced and reduced splicing of intron 4, respectively. RNA mobility shift assays performed with a Motif 8 sequence that contains a CAUC cis -element and cell extracts resulted in a RNA:protein shift that was lost upon mutation of the element. Furthermore, in silico analysis of mRNA secondary structure stability for minigenes with and without motif 8 indicated a correlation between mRNA stability and splicing ratio. We conclude that differential loss of specific intron 4 motifs results in one or more of the following: a) altered splicing, b) differences in RNA stability and c) changes in secondary structure. These, in turn, may affect SP-B content in lung health or disease.