Synthesis of Substituted 2-Amino-Cyclobutanones

A series of weakly nucleophilic nitrogen derivatives including carbamates, amides, sulfonamides, and anilines were reacted with 1,2‐bis(trimethylsilyloxy)cyclobutene under acidic conditions to afford various substituted 2‐aminocyclobutanone derivatives 3a–i in modest to excellent yields

Hazard Assessment for Manufacture of Combustible Cartridge Cases using Picrite

A systematic study of the effect of impact, friction, flame and electric spark sensitivity was carried out on the samples combustible cartridge case (CCC) withdrawn at different stages of manufacture. These are Stage I dried felted CCC; stage II-CCC from stage III Coated with nitrocellulose coating. based on the results obtained from various experiments, the CCC can be classified for handling storage and transportation as Group 3, for safety distance category as UN 1.3 and for fire fighting as class 2. further it is concluded from hazard analysis study that the CCCs are safe to handle but these should be protected from naked flame

Barriers and Determinants of Referral Adherence in AI-Enabled Diabetic Retinopathy Screening for Older Adults in Northern India During the COVID-19 Pandemic: Mixed Methods Pilot Study

\ua9 Anshul Chauhan, Anju Goyal, Ritika Masih, Gagandeep Kaur, Lakshay Kumar, Neha, Harsh Rastogi, Sonam Kumar, Bidhi Lord Singh, Preeti Syal, Vishali Gupta, Luke Vale, Mona Duggal. Background: Diabetic retinopathy (DR) is a leading cause of blindness globally. DR has increasingly affected both individuals and health care systems as the population ages. Objective: This study aims to explore factors and identify barriers associated with nonadherence to referral recommendations among older adult participants after DR screening (DRS) during the COVID-19 pandemic. Method: This paper presents findings from a pilot study on artificial intelligence-enabled DRS conducted in two districts in Punjab, India (Moga and Mohali) during the COVID-19 pandemic. The screenings were conducted from March to June 2022 at community health center Badhani Kalan in Moga and from March to June 2021 in community settings (homes) in Block Boothgarh, Mohali. Participants were referred to the district hospital for an ophthalmological review based on artificial intelligence-enabled screening. After 1 month, the participants were contacted by telephone to assess adherence to the referral recommendations. Participants who did not adhere to the referral were then interviewed alongside health care providers to understand the barriers explaining their nonadherence. Results: We aimed to recruit 346 and 600 older adult participants from 2 sites but enrolled 390. Key challenges included health facility closures due to COVID-19, low motivation among health personnel for recruitment, incomplete nonparticipation data, and high participant workloads. Approximately 45% of the participants were male and 55% female. Most participants (62.6%) were between 60 and 69 years old, while 37.4% were 70 or older, with a mean age of 67.2 (SD 6.2) years. In total, 159 participants (40.8%) were referred, while 231 participants (59.2%) were not. Only 23 (14.5%) of those referred followed through and visited a health facility for ophthalmological review, while 136 (85.5%) did not pursue further evaluation. Our analysis revealed no significant differences in the characteristics between adherent and nonadherent participants, suggesting that demographic and health factors alone do not predict adherence behavior in patients with DR. Interviews identified limited knowledge about DR, logistical challenges, financial constraints, and attitudinal barriers as the primary challenges. Conclusions: This study, conducted during the COVID-19 pandemic, showed suboptimal adherence to referral recommendations among older adult patients due to knowledge gaps, logistical challenges, and health system issues. Quantifying and understanding adherence factors are crucial for targeted interventions addressing barriers to referral recommendations after DRS. Integrating teleophthalmology into and strengthening infrastructure for artificial intelligence-enabled diabetic retinopathy screening to enhance access and outcomes

CFD Analysis of a Micro-Rotor In Ground Effect

In this work, computational fluid dynamics is used to compare experimental results for a two-bladed small rotor Out of Ground Effect and In Ground Effect conditions. The paper focuses on the evalutation and prediction of the performance of the rotor and investigates the outwash generated in ground effect. Time and phase averaged outflow velocities with two different scaling methods are compared with experiments. The results are also scaled to a full-size rotor, and compared with the PAXman model of crew operating in close rotor proximity. A particle pickup model is also used showing the dust cloud generated by the rotor

Patients’ Perspectives, Experiences, and Concerns With Perianal Fistulae:Insights From Online Targeted-Disease Forums

Background: Perianal fistulae can undermine physical, emotional, and social well-being in patients with Crohn’s disease and are challenging to manage. Social media offers a rich opportunity to gain an in-depth understanding of the impact of perianal fistulae on patients’ daily lives outside of controlled environments. In this study, we conducted social media analytics to examine patients’ experiences with perianal fistulae and assessed the impact of perianal fistulae on patients’ behavior and overall well-being. Methods: We used a mixed-method approach to examine 119 986 publicly available posts collected from 10 Crohn’s disease forums in the United States between January 01, 2010 and January 01, 2020. Discussions related to Crohn’s perianal fistulae were retrieved. We randomly selected 700 posts and qualitatively analyzed them using an inductive thematic approach. We then applied a latent Dirichlet allocation probabilistic topic model to explore themes in an unsupervised manner on the collection of 119 986 posts. Results: In the qualitative analysis, 5 major themes were identified: (1) burden of perianal fistula; (2) challenges associated with treatment; (3) online information seeking and sharing; (4) patient experiences with treatments; and (5) patients’ apprehension about treatments. In the quantitative analysis, the percentages of posts related to the major themes were (1) 20%, (2) 29%, (3) 66%, and (4) 28%, while the topic model did not identify theme 5. Conclusions: Social media reveals a dynamic range of themes governing patients’ perspectives and experiences with Crohn’s perianal fistulae. In addition to the biopsychosocial burden, patients frequently express dissatisfaction with current treatments and often struggle to navigate among available management options.</p

Management of difficult airway in intratracheal tumor surgery

BACKGROUND: Tracheal malignancies are usual victim of delay in diagnosis by virtue of their symptoms resembling asthma. Sometimes delayed diagnosis may lead to almost total airway obstruction. For difficult airways, not leaving any possibility of manipulation into neck region or endoscopic intervention, femorofemoral cardiopulmonary bypass can be a promising approach. CASE PRESENTATION: We are presenting a case of tracheal adenoid cystic carcinoma (cylindroma) occupying about 90% of the tracheal lumen. It was successfully managed by surgical excision of mass by sternotomy and tracheotomy under femorofemoral cardiopulmonary bypass (CPB). CONCLUSION: Any patient with recurrent respiratory symptoms should be evaluated by radiological and endoscopic means earlier to avoid delay in diagnosis of such conditions. Femorofemoral cardiopulmonary bypass is a relatively safe way of managing certain airway obstructions

Primary aneurysmal bone cyst of coronoid process

BACKGROUND: Aneurysmal bone cysts are relatively uncommon in the facial skeleton. These usually affect the mandible but origin from the coronoid process is even rarer. To the best of our knowledge, this is the first reported case of a coronoid process aneurysmal bone cyst presenting as temporal fossa swelling. CASE PRESENTATION: A 17 year old boy presented with a progressively increasing swelling in the left temporal region developed over the previous 8 months. An expansile lytic cystic lesion originating from the coronoid process of the left mandible and extending into the infratemporal and temporal fossa regions was found on CT scan. It was removed by a superior approach to the infratemporal fossa. CONCLUSION: Aneurysmal bone cyst of the coronoid process can attain enormous dimensions until the temporal region is also involved. A superior approach to the infratemporal fossa is a reasonable approach for such cases, providing wide exposure and access to all parts of the lesion and ensuring better control and complete excision

CFD Analysis of a Micro-Rotor In Ground Effect

In this work computational fluid dynamics is validated using experimental results for a model rotor In Ground Effect. The paper concentrates on the evaluation and prediction of the performance of the rotors and on the outwash generated In Ground Effect. Finally, safety considerations in terms of outflow forces and particles in the flow field are presented, comparing the results with other safety, distance based criteria. Using data of three different aircraft, scaling factors have been used to take into account the different size of the small-rotor studied and real case scenarios. The results show how heavier helicopters may generate the most dangerous situations, in terms of induced forces and presence of particles in a delimited area

Achievement of the planetary defense investigations of the double asteroid redirection test (DART) mission

Artículo escrito por más de cien autores.NASAʼs Double Asteroid Redirection Test (DART) mission was the first to demonstrate asteroid deflection, and the missionʼs Level 1 requirements guided its planetary defense investigations. Here, we summarize DARTʼs achievement of those requirements. On 2022 September 26, the DART spacecraft impacted Dimorphos, the secondary member of the Didymos near-Earth asteroid binary system, demonstrating an autonomously navigated kinetic impact into an asteroid with limited prior knowledge for planetary defense. Months of subsequent Earthbased observations showed that the binary orbital period was changed by –33.24 minutes, with two independent analysis methods each reporting a 1σ uncertainty of 1.4 s. Dynamical models determined that the momentum enhancement factor, β, resulting from DARTʼs kinetic impact test is between 2.4 and 4.9, depending on the mass of Dimorphos, which remains the largest source of uncertainty. Over five dozen telescopes across the globe and in space, along with the Light Italian CubeSat for Imaging of Asteroids, have contributed to DARTʼs investigations. These combined investigations have addressed topics related to the ejecta, dynamics, impact event, and properties of both asteroids in the binary system. A year following DARTʼs successful impact into Dimorphos, the mission has achieved its planetary defense requirements, although work to further understand DARTʼs kinetic impact test and the Didymos system will continue. In particular, ESAʼs Hera mission is planned to perform extensive measurements in 2027 during its rendezvous with the Didymos–Dimorphos system, building on DART to advance our knowledge and continue the ongoing international collaboration for planetary defense