Limited Extension Research Articles

Toward High-Efficiency and Low-Emissions Hydrogen Direct Injection Internal Combustion Engine: Pre-Chamber Turbulent Jet Ignition

ABSTRACT Hydrogen internal combustion engine (HICE) holds significant promise for transitioning to clean fuels within the transportation field. This research investigates the adaptability of pre-chamber turbulent jet ignition (TJI) in direct injection (DI) HICE, focusing on addressing challenges such as reduced flame speed under lean-burn strategy and high NOx emissions during high-efficiency operation. Using a 3D CFD model of a DI HICE, we explore the impact of different ignition modes on mixing, combustion, and NOx emissions. Our findings reveal that the passive pre-chamber mode leads to a modest improvement in thermal efficiency and a reduction in NOx emissions compared to the spark ignition (SI) mode. In contrast, the active pre-chamber mode, characterized by a faster flame velocity, enhances indicated thermal efficiency (ITE) by about 2% compared to other ignition modes. We identify an optimal injection strategy for the pre-chamber, involving the injection of 0.3 mg of hydrogen. Deviations from this hydrogen quantity adversely reduce the thermal efficiency. Moreover, advancing injection timing promotes fuller mixing at higher turbulent kinetic energy, resulting in faster flame propagation albeit with a marginal rise in NOx emissions. Adjusting the equivalence ratio leads to an extension of the lean burn limit to the equivalence ratio of 0.25, while still achieving efficient combustion with ITE exceeding 49% at equivalence ratios of 0.3 or higher. Ultimately, we demonstrate the attainment of high-efficiency and low-emission combustion, with ITE surpassing 50% and NOx emissions falling below 80 ppm.

Impact of Farmer Cooperatives on Labor Employment: Evidence from Rural China

Farmer cooperatives are one of the types of important entities for agricultural production and rural community development in China. This study aims to examine the effects of farmer cooperatives on rural labor employment and explores the mechanisms from the perspective of institutional advantage, factor redistribution, and value chain. Leveraging two-waved panel data from the China Rural Development Survey, a multinomial Logit model and Tobit model with panel data are adopted. The results show that farmer cooperatives significantly boost rural labor employment, with a more pronounced effect on fully farming and part-time farming. These effects are primarily seen through three mechanisms: income augmentation stemming from institutional advantages, factor redistribution by land transferring and technology service/adoption, as well as industrial clusters. The limited value chain extension of farmer cooperatives hinders its role in improving fully non-agricultural employment. The findings suggest that the government should support the high-quality development of farmer cooperatives to facilitate rural labor employment.

Integration of satellite and aerial images with multichannel GPR surveys in the archaeological area of Augusta Bagiennorum for an improved description of the urban setting

The archaeological area of Augusta Bagiennorum (NW Italy) is a well-known archaeological site, extensively investigated since the end of the 19th century. Previous archaeological studies in the area allowed a preliminary definition of the urban setting through several direct soundings. However, the current knowledge of the site needs to be more complete due to the limited extension of previous archaeological surveys. To obtain a more complete description of the urban setting, we analysed aerial and satellite images and multichannel Ground Penetrating Radar (GPR) surveys, which are two remote-sensing technologies often used in this field. Aerial images showed vegetation cropmark patterns in different areas, depending on the time of the day, year, and camera acquisition setup. The GPR surveys locally confirmed the presence of buried structures in correspondence with the cropmarks, and provided a more detailed view of the underground features. The GPR was also helpful in adding Ground Control Points for georeferencing hot-air balloon images. The combined view of aerial and GPR images allowed us to confirm the overall extent of the archaeological area, as reported in past archaeological reports. However, some of the observed structures were located outside the previously known extent of the town. The orientation of some suggests that the streets of Augusta Bagiennorum are not always arranged in a perpendicular pattern, typical of the Roman orthogonal town planning. The adopted methodological approach could be a valuable tool in similar case studies, since it provides multiscale information composed of both overall views and detailed images.

Milk Value Chain Analysis: The Case of Urban and Peri-Urban Areas of Ambo and Dendi Districts, West Shewa Zone, Oromia National Regional State, Ethiopia

This study was aimed at analyzing value chain of milk in Urban and Peri – Urban areas of Ambo and Dendi districts of West Shewa Zone. The study made use of both primary and secondary data collected from 146 smallholder farmers, 30 consumers, 10 Hotels and Cafeterias and 2 primary milk cooperatives through application of individual interview schedules, focus group discussions and key informant interview. The analysis was made using descriptive statistics and value chain analysis. The value chain analysis revealed that the major actors in the districts milk value chains are input suppliers, milk producers, collectors, processors and consumers. Accordingly, the value chain activities in the chain were input supply, production, processing, marketing and consumption. Four milk marketing channels were identified and relative to all other fresh milk marketing channels, producers get a higher proportion of total gross marketing margin when they sell milk to cooperatives. Profitability analysis result for dairy production indicated that, a dairy producer obtains average gross margin of 83.65per improved cow per day, in the study areas which shows that dairy production was a profitable venture for smallholder dairy producers. Milk value chain in the study areas was hindered by shortage of feeds, continuous increasing price of feeds, poor AI service provision, poor supply of genetically improved cattle breeds, limited availability of credit services, limited extension service provision, poor feeding and animal husbandry practices, low level of market linkage among the value chain actors, absence of milk processing plant and non-market oriented milk production. Therefore, policy aiming at increasing farmers’ access to modern inputs, feed conservation practices, adequate training provision to AI technicians, developing and improving infrastructure, cooperative development and improving extension services are recommended to accelerate the milk value chain’s development in the study areas.

Long-Term Outcomes of Obstetric Brachial Plexus Injury: A Single-Center Experience.

Obstetric brachial plexus injury (OBPI) is an important preventable complication of the birth process. While most cases recover in the early period, a substantial number result in sequelae. Despite established risk factors, there are cases that occur without any apparent risk factors. Our study aims to identify prenatal risk factors by examining OBPI cases born in our hospital and to provide insights into the prognosis of the disease by comparing cases with panplexopathy to those without. We included 31 cases followed for OBPI in our hospital. Risk factors related to the infant and the mother were investigated. The range of motion (ROM) measurements of the affected upper extremity joints, muscle strength, atrophy, and scoliosis status were evaluated. Of the cases, 71% were girls, and 61.3% had left-sided involvement. Additionally, 84.1% had risk factors, with oxytocin administration being the most frequently identified risk factor. In our study, we compared cases with panplexopathy to those without. Shoulder abduction, shoulder adduction, wrist flexion, and wrist extension restrictions were significantly more common in cases with panplexopathy. Furthermore, muscle atrophy was significantly more frequent in the panplexopathy group. Since OBPI is a preventable injury, identifying risk factors is crucial. However, there are conflicting results regarding the most significant risk factor. Our study highlights that oxytocin administration is a very important risk factor for OBPI. We found that cases with panplexopathy had a worse prognosis, with more frequent ROM limitations and muscle atrophy.

Fleet vehicle replacement strategy in the Korean market under phase-out of conventional vehicle

With the recent global requirements to phase out internal combustion engine vehicles (ICEVs), fleet owners (FOs) must consider battery electric vehicles (BEVs) as replacements, introducing regulatory risk due to policy changes. Many countries have legal retirement age limit for fleet vehicles (FVs), considered as policy constraint necessitating eventual replacement. Additionally, uncertainties like fuel price of ICEV and battery price affect the replacement decision. This study proposes an optimal replacement strategy using real option approach for annual decision-making under multiple risk factors. Using data from the Korean FV market, we provide managerial implications. Despite optimistic battery price projections, voluntary BEV switching is not expected to exceed 40% of total FVs. Sensitivity analysis reveals that adjusting the legal retirement age is more effective than changing the BGVSP implementation year. Also, A flexible subsidy based on fuel prices and the extension of the legal retirement age limit through safety inspections should be recommended.

Hydrogen-enriched lean-burn strategy for gasoline direct injection engine utilizing non-thermal plasma fuel reformer

The objective of the task is to sustain and enhance combustion stability at the extension of lean limit of customized Gasoline Direct Injection (GDI) Engine with the supplementation of Hydrogen Rich Gas (HRG) and hydrogen. HRG was supplemented from the on board non thermal Plasma Fuel Reformer (PFR) and hydrogen from the bottled storage through integrated gas control device to the GDI engine. The gas constituents of PFR was theoretically arrived from thermodynamic combustion equations to determine energy based fuel proportion in the ternary fuel injection system. Binary fuel mixture of HRG and hydrogen 10%, 18%, 30% of energy based proportion with gasoline were experimented on test engine. The impact of discrete and binary fuel mixture with gasoline at Stoichiometric Fuel Air ratio was observed and extended baseline equivalence ratio until misfire of the ternary fuel air mixture was occurred. Apart from significant improvement of performance the addition gaseous mixture increases oxides of nitrogen marginally. From the perspective it was noticed that combustion products exhibit better heat transfer out of cylinder at the Maximum Brake Torque Timing (MBT). This was attributed to higher combustion temperatures and improved quenching distances which in turn increased thermal efficiency against the specified equivalence ratio. However retarding MBT suppresses oxides of nitrogen and continued to increase thermal efficiency. It was concluded that lightning fast burn speed, fine fuel atomization of 10% mass based hydrogen and HRG 18%combination fraction increase engine thermal efficiency while decreasing NOx emission and alleviate HC trade-off characteristics.

Influence of steam induction on the performance and hydrogen knock limit of a hydrogen-gasoline spark ignition engine

This study examines the effect of steam induction on the performance and hydrogen knock limit of a hydrogen-gasoline dual-fuel Spark Ignition (SI) engine. The experimental setup includes gasoline direct injection, along with steam and hydrogen port induction. Steam-to-fuel ratios of 7.5 %, 15 %, and 22.5 % were used, and hydrogen was introduced in step sizes of 2 LPM until knock onset. The extension of the hydrogen knock limit was achieved through steam induction and retarding spark timing. Under the default configuration, the maximum achievable hydrogen flow rate was 8 LPM, which increased to 20 LPM with retarded spark timing and 22.5 % steam proportion. Steam induction initially increased and then decreased brake thermal efficiency, brake mean effective pressure, in-cylinder pressure, and heat release rate. In contrast, advancing spark timing and hydrogen enrichment consistently improved performance and combustion characteristics. Cyclic variation showed a decreasing trend with the introduction of steam and hydrogen. Unlike hydrogen enrichment, steam addition reduced CO and NOX emissions.

Reply to Comment on “Singh R, Vadlamani R, Bajpai S & Maurya AS (2024) Strontium Isotope Stratigraphy of Marine Oligocene–Miocene Sedimentary Successions of Kutch Basin, Western India. Geological Journal, 1–20. DOI: 10.1002/gj.4961”

ABSTRACTThis response addresses the comments made by Saraswati et al. on our recent publication in Geological Journal. In our study, we used a multi‐analytical screening approach, including visual, XRD and trace element analysis, to evaluate diagenetic alteration of carbonate shell samples. Contrary to the claims made by Saraswati et al. our findings are based on well‐preserved samples with minimal alteration. The Sr‐isotope data from the Khari Nadi Formation (23.07–18.09 Ma) are largely consistent with existing biostratigraphic constraints, but suggest a possible extension of the upper age limit into the Burdigalian. Our Sr‐isotope ages for the Chhasra Formation (15.11–12.29 Ma) are younger than those suggested previously, based on larger benthic foraminifers, but largely corroborate recent nannoplankton data. As a result of the new age data from Kutch, we suggest that the sedimentation rates, derived from multiple samples, increased significantly from the Oligocene to Miocene. We assert that ‘established’ ages are also subject to refinements as the rock units become amenable to new dating techniques. We welcome any criticism that is constructive, and remain open to any further data that could refine or challenge our interpretations.

Feasibility study of underground CO2 storage through Water Alternative Gas (WAG) operation: A case study in Southwestern Ontario

Geological CO2 storage (GCS) offers a promising, low-risk, long-term solution for carbon sequestration. This study assesses the feasibility of GCS water-alternating-gas (WAG) operations in a brine formation targeted for the Western Ontario GCS plan. The Cambrian strata shows potential for CO2 storage but faces challenges like limited lateral extension and geopolitical issues from plume migration. To mitigate these risks, a deep evaluation of CO2 trapping mechanisms is crucial. CO2 dissolution into brine provides secure storage by reducing the free plume. The proposed WAG operation promotes dissolution, using a vertical equilibrium model coupled with a black oil model to estimate CO2 trapping proportions during and post-injection. The Taguchi design of experiments investigates various WAG scenarios with minimal simulations, reducing numerical costs. Sensitivity analysis/optimization of WAG parameters, including water extraction rate (WER), water injection rate (WIT), and CO2 injection time (CIT), ranked their effectiveness in CO2 dissolution. Optimal WAG operations can reduce the free plume by 49 % and increase the dissolution ratio from 0.26 to 0.52. CIT and WIT were found to be the most influential factors, contributing 42 % and 31 % to CO2 dissolution, and 43 % and 34 % to overall CO2 trapping, respectively, while WER exhibited a lower impact of 8–9%.

Surgical Management for Boutonniere Disease

Boutonniere disease is a hand injury causing extension lag or restriction in the proximal interphalangeal joint and hyperextension in the distal interphalangeal joint. This condition often arises from direct laceration or closure damage to the central tendon, rheumatoid arthritis, osteoarthritis, Dupuytren contracture, pulley injury, burns, and other conditions. Surgical management for Boutonniere deformity relies on the expertise of the attending physician and involves both non-surgical and surgical options. In acute cases, conservative therapy should be pursued, while in chronic cases, conservative management may be advised. Surgical intervention is used to transform excessive extension force of the distal interphalangeal joint into extension force of the proximal interphalangeal joint. This is necessary to heal an open rupture of the central tendon. Surgical techniques for chronic deformity are complex due to variables and hand surgeons' expertise. There is no definitive surgical therapy for persistent buttonhole deformity, but several approaches have been documented in case studies. These include terminal tenotomy, collateral band surgery, central tendon surgery, tendon transfer and grafting, stepwise extension mechanism readjustment surgery, and arthrodesis. Central tendon surgery addresses the central tendon, where injured tissue transforms into scar tissue, resulting in delayed extension of the proximal interphalangeal joint. Tendon transfer or grafting have been documented for rotator cuff mechanism rehabilitation, but no definitive guidance exists for these techniques. Curtis treatment introduced a sequential therapy approach for traumatic buttonhole deformity, which involves splinting, excising the transverse reticular ligament, resecting and lengthening the collateral ligament, and repositioning the core tendon. Arthrodesis may be applicable in cases of advanced arthritis, coronal plane deformity, functional impairment, or elderly patients. There are no definitive indications for surgical interventions for persistent buttonhole deformity, and outcomes may be variable or inferior. Understanding the deformity, its progression, and patient's functional constraints is crucial for effective treatment

Frustrative Nonreward: Behavior, Circuits, Neurochemistry, and Disorders.

The surprising omission or reduction of vital resources (food, fluid, social partners) can induce an aversive emotion known as frustrative nonreward (FNR), which can influence subsequent behavior and physiology. FNR is an integral mediator of irritability/aggression, motivation (substance use disorders, depression), anxiety/fear/threat, learning/conditioning, and social behavior. Despite substantial progress in the study of FNR during the twentieth century, research lagged in the later part of the century and into the early twenty-first century until the National Institute of Mental Health's Research Domain Criteria initiative included FNR and loss as components of the negative valence domain. This led to a renaissance of new research and paradigms relevant to basic and clinical science alike. The COVID-19 pandemic's extensive individual and social restrictions were correlated with increased drug and alcohol use, social conflict, irritability, and suicide, all potential consequences of FNR. This article highlights animal models related to these psychiatric disorders and symptoms and presents recent advances in identifying the brain regions and neurotransmitters implicated.

HaptiYarn: Development of an Actuator Yarn That Can Transform Everyday Textiles Into Haptic Devices.

A method of providing localised haptic feedback at precise locations on the body, utilising a lightweight textile garment is presented in this short paper. The textile comprises of subtly integrated actuator yarns (HaptiYarns) which are controlled by electropneumatic circuitry. Each yarn has two functional layers, an inner porous textile layer with limited extensibility and a second, durable outer layer made from an extensible elastomer. The HaptiYarns can provide radial forces and a maximum radial displacement of 28.09 ± 0.14 mm. It was found that the intrinsic addition of graphite powder (5% by weight), during elastomer preparation, offered better resistance to layer delamination and increased the ability of the yarn to withstand higher internal air pressures by 48%. Both the graphite-filled composite and the graphite free yarns demonstrated high durability, withstanding cyclic testing of >7500 cycles while having no significant impact on the force feedback. Finally, a wearable prototype knitted textile garment is presented with eight HaptiYarns subtly integrated within it and connected to a virtual reality (VR) program providing an immersive haptic experience. These yarns offer the potential to transform everyday clothing into wearable haptic devices with potential to revolutionise healthcare, VR-based training, gaming, and entertainment sectors.

Predictors of Gait Variability in Older Inpatients: An Exploratory Study Among Orthopedic Patients.

Aim Older inpatients have reduced physical function and walking ability with a higher risk of falls after being discharged home. Gait variability can assess ambulation and is strongly related to the risk of falls. However, the clinical factors affecting gait variability in inpatients have not been identified. The purpose of this study was to investigate the predictive factors affecting gait variability in older inpatients. Methods A total of 42 older orthopedic inpatients with fractures of the hip, spine, and other segments and 18 healthy volunteers as the control group were enrolled in this study. Inpatients wore tri-axial accelerometers for a 10m walk before discharge. Gait variability was assessed by the coefficient of variation (CV) based on five consecutive stride times. Clinical assessment of muscle strength, joint mobility, balance, pain, and activities of daily living were also evaluated. Results The CV in inpatients was higher than that in healthy elderly. Quadriceps muscle strength, ankle dorsiflexion range of motion, and balance described the CV. When model 2 (adjusted R2 = 0.473) was compared with model 1 (adjusted R2 = 0.293), the quadriceps muscle strength and ankle dorsiflexion range of motion had a major effect on CV, while balance had not a greater influence than these two factors when compared with model 3 (adjusted R2 = 0.537). Conclusions Poor knee extension strength, balance, and restriction of ankle dorsiflexion mobility have influenced gait variability in older inpatients.

A Prospective Study for the Comparative Evaluation of Pediatric and Adult Cholesteatoma

Abstract Aim: To determine the extent of cholesteatoma by imaging and intraoperative findings in both pediatric and adult category. Objectives: To study the extent of disease (cholesteatoma); (a) Radiologically (HRCT-Temporal Bone) and (b) Intraoperatively, to study the post-op hearing outcome and to study the healing period (dry cavity/ epithelization of cavity) following surgery in pediatric and adult category. Materials and Method: A prospective observational study was conducted on 60 patients of chronic otitis media with cholesteatoma. Each category had 30 patients, all of which were subjected to thorough preoperative clinical examination and HRCT temporal bone scans. The scans were evaluated with the help of Lynrah et al. grading for the radiological extension of disease. The same grading system was applied for the intraoperative extension of disease. All the patients were scrutinized for upto 6 months for the follow up of mastoid cavity epithelisation and post operative hearing gain results. Results: The majority of the patients in both the categories had Grade II disease extension, illustrated in their radiological as well as intraoperative findings signifying an excellent correlation amongst the two. The epithelization of mastoid cavity postoperatively was delayed in pediatric group due to presence of huge voluminous mastoid pneumatisation. The postoperative hearing gain results were good in both the categories. Conclusion: It was concluded that limited extension of disease with early diagnosis and timely intervention in pediatric group could result in favorable prognosis in terms of healing of mastoid cavity postoperatively and hearing gain results.

Is there an association between arteriovenous fistulas and axillary artery aneurysms? A report of two cases

IntroductionAxillary artery aneurysms are rare vascular conditions that can present with various clinical manifestations, including neurological deficits and vascular compromise. While the underlying pathophysiology remains complex and multifactorial, potential associations with trauma, arteriovenous fistula formation, and atherosclerosis have been reported.Presentation Of Case.Two male patients, aged 33 and 38, with a history of kidney transplantation and previous arteriovenous fistula (AVF) presented with symptoms of upper limb ischemia and neurological compromise. Imaging revealed large axillary artery aneurysms. Open surgical repair was performed for both cases. Two weeks after discharge, one patient showed good pronation and supination with mildly limited extension. The other patient's wrist drop gradually improved with physiotherapy. DiscussionMultifactorial pathophysiology encompassed altered blood flow dynamics, inflammation, and the underlying vascular pathology. Chief complaints and prior vascular interventions contributed. Open surgical repair was preferred to endovascular approaches, achieving favorable outcomes. ConclusionAxillary artery aneurysms in patients with a history of AVF are rare but potentially serious complications. The cases highlight the complexity of axillary artery aneurysms and the need for careful evaluation and surgical intervention This strategy is crucial to prevent potential complications and optimize patient outcomes. Further research is needed to elucidate the precise pathophysiology and the potential association between AVF and the subsequent development of axillary artery aneurysms. Increasing awareness among surgeons could enable earlier detection of aneurysms, thereby reducing the risk of complications.

Adoption of Black Plastic Mulch as a Coping Strategy to Water Conservation Among Vegetable Farmers in Kisoro Municipality, Kisoro District

The study was about the adoption of black plastic mulches as a copying strategy to water conservation among smallholder vegetable farmers in Kisoro Municipality, Kisoro district. Farmers in Kisoro District have increasingly adopted black plastic mulch to address these agricultural challenges. The use of black plastic mulch in this region helps in conserving soil moisture, controlling weeds, and enhancing crop yields. It was guided by three specific objectives which were to; establish the socio-economic characteristics of smallholder vegetable farmers, establish the knowledge level on the benefits of black plastic mulch among smallholder vegetable farmers and examine the factors influencing farmer’s decision to adopt black plastic mulch as a coping strategy to water conservation. The study employed a cross-sectional study design that used both quantitative and qualitative approaches. The study used a sample size of 300. The study used questionnaires and interview guide to collect data. The data collected was analysed using Statistical Package for Social Scientists (SPSS). The results revealed that land ownership was a positive and significant factor at (sig. 0.000**), source of income at (sig.0.001*), credit accessibility at (sig.0.002**) and knowledge on use of black plastic mulches at (sig. 0.000**) The study concluded that vegetable farmers were characterized in terms of gender, age, farm size, marital status and level of education. The study also concluded that there was adequate knowledge level on the benefits of black plastic mulch among smallholder vegetable farmers. Such as; leads to higher yields and improved quality of vegetables, increase the growth rate of vegetables, reduce the risk of root damage, weed suppression, moisture conservation and contribute to soil health and protect the soil from wind and water erosion. The study finally concluded that there were significant and non-significant factors influencing farmer’s decision to adopt black plastic mulch as a coping strategy to water conservation among smallholder vegetable farmers which included; land ownership, limited extension training, source of income, knowledge on use of black plastic mulches and credit accessibility and non-significant ones were; un-availability of labour, infrastructure development, level of education, price of black plastic mulch and farm size.

The Impact of Pronator Quadratus Origin Release on the Clinical Outcomes of Scaphoid Nonunion Patients Treated with Pronator Quadratus Pedicled Bone Grafts.

Background/Objectives: A pronator quadratus pedicled bone graft (PQPBG) is a distal radius volar vascularized bone graft used not only for avascular necrosis of the lunate but also for scaphoid nonunion. Despite its potency and its possession of a muscular shield, this vascularized graft has a disadvantage in that the potential shortness of the muscular leash may limit the distal transfer of the bone graft. Releasing of the pronator quadratus (PQ) ulnar origin was used to enhance the distal mobility of the graft. We aimed to investigate the effect of a PQ release on the surgical outcomes of scaphoid nonunions that were operated on with the PQPBG technique. Methods: Patients with scaphoid nonunion that were treated with PQPBG from 2009 to 2020 were reviewed. Patient demographic characteristics, surgical notes, physical examinations, and radiological evaluation data were collected. Wrist range of motion, grip strength, modified Mayo wrist score, and Quick-DASH score were used to evaluate the outcomes. The included patients were divided into two groups based on the origin release status of their PQ, i.e., with and without release. Results: This study included 37 patients, 17 of whom underwent a PQ release and 20 of whom did not. The failure rates for the two groups were one and four patients, respectively, and there was no significant difference between them (p = 0.11). The postoperative mean wrist extension in the patients with a PQ release was significantly greater than that in the patients without a release (43.5 ± 6.8 vs. 36.5 ± 7.7, p = 0.0038). Although wrist flexion, ulnar deviation, radial deviation, mean outcome assessment scores, and grip strength were greater in the patients with a PQ release than in those without, no statistically significant intergroup differences were observed (p > 0.05). Conclusions: The PQPBG technique is a viable option for achieving bony union in patients with scaphoid nonunion, but it results in the postoperative restriction of wrist extension. PQ release during a graft transfer may have a favorable effect on both bone union and clinical outcomes.

Influence of ethanol–gasoline–hydrogen and methanol–gasoline–hydrogen blends on the performance and hydrogen knock limit of a lean-burn spark ignition engine

This study investigates the effects of ethanol–gasoline and methanol–gasoline blends on the performance of a lean-burn spark ignition engine and the hydrogen knock limit of the engine with hydrogen-enriched fuel. The experimental setup includes liquid in-cylinder fuel injection and hydrogen port induction. Ethanol and methanol are blended with pure gasoline up to 50% by volume (20%, 35% and 50%) and all fuels are drip-fed with hydrogen until combustion knock is detected in step size of 2LPM. The hydrogen knock limit extension is achieved with ethanol–gasoline and methanol–gasoline blends and is further extended by spark-timing retardation. Retarded spark timing and ethanol–methanol blended fuels reduce the brake thermal efficiency, brake mean effective pressure, and peak in-cylinder pressure. The cyclic variation increases with ethanol and methanol addition and decreases with spark-timing retardation and hydrogen enrichment. Unlike hydrogen enrichment, ethanol and methanol addition reduce the CO2 and NOx emissions but increase the CO emission.

Olfaction Preservation and Long-Term Outcomes in Patients with Unilateral Endoscopic Resection of Olfactory Neuroblastoma: A Systematic Review and Institutional Experience

BackgroundEndoscopic endonasal surgical resection is an effective therapeutic approach for olfactory neuroblastoma (ONB). Unilateral excision of ONBs with limited extension has been reported with the purpose of preserving olfactory function. We aimed to review implications of surgical management, olfactory preservation feasibility, and survival outcomes in patients who underwent endoscopic unilateral resection of olfactory neuroblastoma. MethodsA systematic literature review was conducted using the search terms [(“Olfactory neuroblastoma”) OR (“Esthesioneuroblastoma”)] AND [(“Unilateral resection”) OR (“Olfaction preservation”)]. Studies reporting cases of unilateral olfactory neuroblastoma endoscopic resection with postoperative olfaction assessment were included. Concurrently, records of patients who met inclusion criteria at our institution were reviewed retrospectively. The survival and olfactory outcomes were analyzed in both cohorts. ResultsThirty-three patients were identified in the published literature. Twenty-three (69.7%) reported postoperative olfaction preservation. Olfactory function after surgery did not show an association with Kadish stage (p=0.128). No evidence of disease was observed at the latest follow-up in this group of patients. Nine patients who met inclusion criteria were identified at our institution. The extent of resection influenced the level of olfaction preservation when cribriform plate and nasal septum resection coexisted (p=0.05). A single patient at our institution developed recurrence after being lost to follow-up for 22 months. ConclusionsOlfaction preservation can be achieved in patients who undergo endoscopic unilateral resection and adjuvant radiotherapy. The extent of resection should aim for negative margins, particularly in the midline. Larger studies are required to assess the risk of contralateral microscopic disease, and, hence, close follow-up is advised.