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1.
Org Process Res Dev ; 26(9): 2674-2684, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36158467

RESUMO

We report the development of a single-pass electrochemical Birch reduction carried out in a small footprint electrochemical Taylor vortex reactor with projected productivities of >80 g day-1 (based on 32.2 mmol h-1), using a modified version of our previously reported reactor [Org. Process Res. Dev. 2021, 25, 7, 1619-1627], consisting of a static outer electrode and a rapidly rotating cylindrical inner electrode. In this study, we used an aluminum tube as the sacrificial outer electrode and stainless steel as the rotating inner electrode. We have established the viability of using a sacrificial aluminum anode for the electrochemical reduction of naphthalene, and by varying the current, we can switch between high selectivity (>90%) for either the single ring reduction or double ring reduction with >80 g day-1 projected productivity for either product. The concentration of LiBr in solution changes the fluid dynamics of the reaction mixture investigated by computational fluid dynamics, and this affects equilibration time, monitored using Fourier transform infrared spectroscopy. We show that the concentrations of electrolyte (LiBr) and proton source (dimethylurea) can be reduced while maintaining high reaction efficiency. We also report the reduction of 1-aminonaphthalene, which has been used as a precursor to the API Ropinirole. We find that our methodology produces the corresponding dihydronaphthalene with excellent selectivity and 88% isolated yield in an uninterrupted run of >8 h with a projected productivity of >100 g day-1.

2.
Curr Anesthesiol Rep ; 11(1): 64-68, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33519304

RESUMO

PURPOSE OF REVIEW: "Distance-learning" encompasses a variety of didactics, from self-directed online learning to focused courses and programs. Despite increasing internet availability, focused distance-learning courses are rarely practiced in low- or middle-income countries, particularly among non-physician anesthetists. This review aims to discuss the availability, significance, and challenges of distance-learning programs for non-physician anesthesia providers in low-resource settings. RECENT FINDINGS: Task shifting and sharing in anesthesia remains essential in low-resource settings to meet the demand of surgical need. Distance-learning may be the ideal option in these settings, as it can be used to train the individual at their workplace even in remote areas. Different models and techniques are described. Success depends on the course design, communication strategies, handling of technical issues, and support mechanisms. SUMMARY: Distance-learning should be an essential part of training and in-service support for non-physician anesthetists. Global advocates of safe, effective anesthesia services need to support the development and delivery of distance-learning courses.

3.
Br J Pain ; 14(4): 238-249, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33194188

RESUMO

INTRODUCTION: Chronic pain is one of the most prevalent causes of disability worldwide, and digital interventions may be one of the ways to meet this need. Randomised controlled trials have demonstrated that digital interventions can be effective in treating chronic pain. This study aimed to establish the clinical effectiveness of a web-based pain management programme (PMP), specifically whether it would lead to improved clinical outcomes and reduced health care costs in a real-world clinical setting. METHODS: Of 738 participants, 438 engaged with the programme and 300 did not. Two analyses were conducted: a within-subjects pre-post comparison of clinical outcomes for participants who completed the programme and a between-groups comparison of health care usage for those who engaged and those who did not. RESULTS: Participants who completed the programme made significant improvements with regard to their perceived health status, level of disability, mood, confidence managing pain, problems in life due to pain and level of pain. Around one-third of participants made reliable changes in their levels of disability, depression and anxiety. There was no relationship between gender or age and engagement with the programme. Those who engaged with the programme demonstrated reduced health care costs in the year following referral, whereas health care costs of non-engagers increased. Limitations of the study include a high drop-out rate and a non-randomised comparison group. Results must therefore be interpreted with some caution. CONCLUSION: A web-based pain management programme can be clinically effective and may be a useful addition to the treatments offered by pain management services.

4.
Environ Sci Technol ; 51(21): 12727-12736, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29017318

RESUMO

The high cost and energy intensity of virgin carbon fiber manufacture provides an opportunity to recover substantial value from carbon fiber reinforced plastic wastes. In this study, we assess the life cycle environmental implications of recovering carbon fiber and producing composite materials as substitutes for conventional and proposed lightweight materials in automotive applications (e.g., steel, aluminum, virgin carbon fiber). Key parameters for the recycled carbon fiber materials, including fiber volume fraction and fiber alignment, are investigated to identify beneficial uses of recycled carbon fiber in the automotive sector. Recycled carbon fiber components can achieve the lowest life cycle environmental impacts of all materials considered, although the actual impact is highly dependent on the design criteria (λ value) of the specific component. Low production impacts associated with recycled carbon fiber components are observed relative to lightweight competitor materials (e.g., aluminum, virgin carbon fiber reinforced plastic). In addition, recycled carbon fiber components have low in-use energy use due to mass reductions and associated reduction in mass-induced fuel consumption. The results demonstrate environmental feasibility of the CFRP recycling materials, supporting the emerging commercialization of CF recycling technologies and identifying significant potential market opportunities in the automotive sector.


Assuntos
Carbono , Reciclagem , Fibra de Carbono , Plásticos , Aço
5.
World J Surg ; 41(12): 3006-3011, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29038830

RESUMO

BACKGROUND: Across Nepal, anesthesia at a district level is provided mostly by non-doctor anesthesia providers (anesthesia assistants-AAs). Nepal's Government recognized the need to sustain competence with continuous professional development and to upgrade 6-month trained working AAs to professional equivalence with the new national standard of 12-month training. As they are essential district health workers and AA clinical training sites are full, an innovative distance blended learning, competency-based, upgrade 1-year course was developed and conducted in 2014-2017 for two batches. METHODS: The course content was developed over 18 months by a team of Nepali and overseas AA training experts. The 1-year course started with a refresher course, continued with tablet-based 12-month self-learning modules and clinical case logs, regular educational mentor communication, midcourse 2-week contact time in an AA training site, regular text messaging and ended with clinical examination and multiple-choice questions. Tablet content included 168 new case studies, pre- and posttests, video lectures, matching exercises and a resource library. All module work and logged clinical cases were uploaded centrally, where clinical mentors were able to review work. Clinical skills were upgraded, as needed, through direct clinical contact midway through the course. Quantitative and qualitative course assessments were included. RESULTS: Fourteen working AAs in first batch and eight working AAs in second batch from district, zonal and mission hospitals across Nepal were enrolled. All remained working at their hospitals throughout the course, and there were no significant tablet problems inhibiting course completion. Twenty-one AAs completed all modules successfully with time required for module completion averaging 19.2 h (range 11.2-32). One AA left the course after 3 months with a personal problem. Subjectively, AAs felt that the obstetric and pediatric modules were more difficult; lowest marks were objectively seen in the airway module. Clinical mentors averaged 8.2 h mentoring review work per module with direct student communication of 2.9 h per module per month. Participants logged a total of 5473 clinical cases, ranging between 50 and 788 cases each. Complications were recorded; outcomes were good. Challenges were the national IT infrastructure making data synchronization difficult and the lack of clinical exposure at some AA's hospitals. Nineteen AAs attended the final examination, and all passed. Two AAs withdrew before the final examination period due to personal and logistic reasons. CONCLUSION: This is the first use of distance blended learning to upgrade district health workers in Nepal and perhaps for non-doctor anesthesia providers globally. Key success factors were motivated students, cultural and contextualized clinical content, good educational mentoring relationships with regular communication, central IT and motivational support, and face-to-face midcourse clinical contact time.


Assuntos
Anestesiologia/educação , Competência Clínica , Educação a Distância , Pessoal de Saúde/educação , Currículo , Educação a Distância/métodos , Humanos , Motivação , Nepal
6.
Org Process Res Dev ; 21(7): 1042-1050, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28781513

RESUMO

We report the construction and use of a vortex reactor which uses a rapidly rotating cylinder to generate Taylor vortices for continuous flow thermal and photochemical reactions. The reactor is designed to operate under conditions required for vortex generation. The flow pattern of the vortices has been represented using computational fluid dynamics, and the presence of the vortices can be easily visualized by observing streams of bubbles within the reactor. This approach presents certain advantages for reactions with added gases. For reactions with oxygen, the reactor offers an alternative to traditional setups as it efficiently draws in air from the lab without the need specifically to pressurize with oxygen. The rapid mixing generated by the vortices enables rapid mass transfer between the gas and the liquid phases allowing for a high efficiency dissolution of gases. The reactor has been applied to several photochemical reactions involving singlet oxygen (1O2) including the photo-oxidations of α-terpinene and furfuryl alcohol and the photodeborylation of phenyl boronic acid. The rotation speed of the cylinder proved to be key for reaction efficiency, and in the operation we found that the uptake of air was highest at 4000 rpm. The reactor has also been successfully applied to the synthesis of artemisinin, a potent antimalarial compound; and this three-step synthesis involving a Schenk-ene reaction with 1O2, Hock cleavage with H+, and an oxidative cyclization cascade with triplet oxygen (3O2), from dihydroartemisinic acid was carried out as a single process in the vortex reactor.

7.
Anesth Analg ; 125(4): 1337-1341, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28504991

RESUMO

BACKGROUND: To meet the need for essential surgery across rural Nepal, anesthesia at district level is delivered by nondoctor anesthetists. They require support to maintain confidence and competence, and upgraded professional registration to secure their status. To meet these needs, a distance-blended learning course was pioneered and delivered. A core course requirement was to log all clinical cases; these were logged on a new e-logbook. METHODS: Fourteen nondoctor anesthesia providers working in 12 different districts across Nepal were enrolled in the 1-year course. The course is based on self-completion on a tablet loaded with new learning modules, a resource library, and a case logbook. Continuous educational mentoring was provided by anesthesiologists by phone and email. The logbook included preanesthesia assessment and interventions, American Society of Anesthesiologists (ASA) grading, types of cases and anesthesia given, monitors used, complications, outcomes and free text remarks. Cases were uploaded monthly to a database, and mentors reviewed all logbook entries. RESULTS: The 14 nondoctor anesthesia providers were widely distributed across the country in district, zonal, community, and mission hospitals, and had different levels of clinical experience and caseloads. Logbooks and uploads were regularly completed without difficulty; 1% cases were entered incompletely with no case details provided. A total of 4143 cases were recorded. Annual caseload per nondoctor anesthesia provider ranged from 50 to 788, the majority of which were under spinal anesthesia; 34% of the total cases were cesarean deliveries, of which 99% received spinal anesthesia. Fifty gastrointestinal laparotomies (1% total) were recorded. Ninety-one percent of cases were ASA I, 0.8% ASA III/IV. Pulse oximetry was used in 98% of cases. Complications were recorded in 6% of cases; the most common were circulation problems (69%) including hypotension and occasional bradycardia after spinal anesthesia. Airway complications were usually under ketamine anesthesia requiring basic airway maneuvers; 4 difficult intubations were recorded under general anesthesia. Anesthesia outcomes were good with overall mortality of 0.1% (total 4 cases). Causes of death included severe preeclampsia, sepsis postlaparotomy, and patients with multiorgan failure for minor procedure. CONCLUSIONS: The tablet-based electronic anesthesia logbook was successfully used to record cases, complications, and outcomes across rural Nepal. The nondoctor anesthesia providers had trust and confidence in recording outcomes. It remains to be tested whether an e-logbook would be routinely completed outside of a specific training course. Such a logbook could be incorporated into all continuous professional development programs for rural nondoctor anesthetists.


Assuntos
Anestesia/métodos , Computadores de Mão/estatística & dados numéricos , Registros Eletrônicos de Saúde , Pessoal de Saúde/educação , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Anestesia/normas , Competência Clínica/normas , Registros Eletrônicos de Saúde/normas , Feminino , Pessoal de Saúde/normas , Necessidades e Demandas de Serviços de Saúde/normas , Humanos , Masculino , Nepal/epidemiologia
8.
Compend Contin Educ Dent ; 38(2): e9-e12, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28156120

RESUMO

BACKGROUND: Immediately placed/immediately restored dental implants in the esthetic zone are judged by not only their functional success but also the appearance and acceptance of the restorative outcome. The purpose of this study was to retrospectively evaluate in a private-practice setting the satisfaction of both patients and doctors regarding immediately placed/immediately restored implants in the esthetic zone. METHODS: The author group consists of nine board-certified periodontists. Each private practice contributed to the patient population of this study through a primarily referral-based source. In a 6-month period, practices evaluated patients who were candidates for dental implant replacement with teeth Nos. 5 through 12 scheduled for extraction. All patients received informed consent and were asked if their data could be used with a visual analog scale (VAS) they graded. Pretreatment and 6-month post-final restoration loading was compared for statistically significant changes in reference to crestal bone changes, papilla index score (PIS), facial gingival margin stability (FGMS), and investigator/patient esthetic evaluations using a VAS. RESULTS: Thirty-five patients were included in the study with a total of 35 implants placed and 32 restored with a final restoration. Implants were followed for an average of 15.4 months prior to reporting. A total of three failures were encountered. The PIS resulted in an average score of 2.7. VAS resulted in an average score of 9.3 by the surgeons and 9.5 by the patients. The FGMS accounted for 76% of the implants with no change, 15% demonstrating recession, and 9% demonstrating coronal migration. CONCLUSIONS: Immediately placed and immediately temporized implants in the esthetic zone demonstrated a successful outcome that was highly acceptable to patients in private-practice settings from a diverse group of private periodontal practices.


Assuntos
Implantes Dentários para Um Único Dente , Restauração Dentária Permanente/métodos , Estética Dentária , Satisfação do Paciente , Restauração Dentária Permanente/instrumentação , Humanos , Prática Privada , Estudos Retrospectivos , Estados Unidos
9.
J Clin Periodontol ; 43(12): 1188-1199, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27617409

RESUMO

AIM: To compare the effectiveness of two-ridge preservation treatments. MATERIALS AND METHODS: Forty subjects with extraction sockets exhibiting substantial buccal dehiscences were enrolled and randomized across 10 standardized centres. Treatments were demineralized allograft plus reconstituted and cross-linked collagen membrane (DFDBA + RECXC) or deproteinized bovine bone mineral with collagen plus native, bilayer collagen membrane (DBBMC + NBCM). Socket dimensions were recorded at baseline and 6 months. Wound closure and soft tissue inflammation were followed post-operatively, and biopsies were retrieved for histomorphometric analysis at 6 months. RESULTS: Primary endpoint: at 6 months, extraction socket horizontal measures were significantly greater for DBBMC + NBCM (average 1.76 mm greater, p = 0.0256). Secondary and Exploratory endpoints: (1) lingual and buccal vertical bone changes were not significantly different between the two treatment modalities, (2) histomorphometric % new bone and % new bone + graft were not significantly different, but significantly more graft remnants remained for DBBMC; (3) at 1 month, incision line gaps were significantly greater and more incision lines remained open for DFDBA + RECXC; (4) higher inflammation at 1 week tended to correlate with lower ridge preservation results; and (5) deeper socket morphologies with thinner bony walls correlated with better ridge preservation. Thirty-seven of 40 sites had sufficient ridge dimension for implant placement at 6 months; the remainder were DFDBA + RECXC sites. CONCLUSION: DBBMC + NBCM provided better soft tissue healing and ridge preservation for implant placement. Deeper extraction sockets with higher and more intact bony walls responded more favourably to ridge preservation therapy.


Assuntos
Processo Alveolar , Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Animais , Transplante Ósseo , Bovinos , Colágeno , Humanos , Membranas Artificiais , Extração Dentária , Alvéolo Dental
10.
Waste Manag ; 48: 465-470, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26542830

RESUMO

Supercapacitors are widely used in electric and hybrid vehicles, wind farm and low-power equipment due to their high specific power density and huge number of charge-discharge cycles. Waste supercapacitors should be recycled according to EU directive 2002/96/EC on waste electric and electronic equipment. This paper describes a recycling approach for end-of-life supercapacitors based on shredding and mild thermal treatment. At first, supercapacitors are shredded using a Retsch cutting mill. The shredded mixture is then undergone thermal treatment at 200°C to recycle the organic solvent contained in the activated carbon electrodes. After the thermal treatment, the mixture is roughly separated using a fluidized bed method to remove the aluminium foil particles and paper particles from the activated carbon particles, which is subsequently put into water for a wet shredding into fine particles that can be re-used. The recycled activated carbon has a BET surface area of up to 1200m(2)/g and the recycled acetonitrile has a high purity.


Assuntos
Carbono/química , Fontes de Energia Elétrica , Eletrodos , Reciclagem , Acetonitrilas/química , Adsorção , Alumínio/química , Boratos/química , Eletrólitos , Eletrônica , Temperatura Alta , Cinética , Nitrogênio/química , Polímeros/química , Solventes/química , Tetraetilamônio/química , Termogravimetria , Água/química
11.
J Am Coll Dent ; 82(1): 5-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26455044

RESUMO

The traditional group practice model can take many forms, including general practitioners, specialists, and combinations, as well as solo practitioners sharing space and staff, partnerships, and other legal entities. These practices may share some or all staff functions, including contracting for some functions. The essential characteristic is that those treating patients also have full control over and often direct management of the business aspects of the practice. The most important requirements for success in this model may be a common philosophy of patient care and mutual trust regarding business matters.


Assuntos
Prática Odontológica de Grupo/organização & administração , Modelos Organizacionais , Prática Odontológica Associada/organização & administração , Administração da Prática Odontológica/organização & administração , Humanos
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