by Ann Lee  and Shaokoon Cheng

Received: 26 March 2023;  Published: 18 September 2023;  doi: 10.21926/jept.2303029

In the context of decarbonization efforts, heat pump water heaters (HPWHs) offer an attractive solution over conventional electric resistance type hot water systems due to their 2-3 times higher efficiency. However, the high manufacturing costs and taxes associated with using hydrofluorocarbon (HFC) refrigerant make HPWHs expensive. As a means to tackle this issue, this paper explores the use of propane (R290) as a refrigerant in HPWHs. The study involves an experimental comparison of R290 and R134a, with refrigera [...]

by Janika Epe  , Rudolf Stark  and Ulrich Ott

Received: 29 June 2021;  Published: 18 September 2021;  doi: 10.21926/obm.icm.2103031

Yogic breathing techniques are fundamental to the physical and mental practice of yoga. They are closely connected to meditation, which involves the observation of breath. There are many yogic techniques based on the active regulation of the breath. Breathing practices influence many processes in the body, e.g. heart rate variability, and the mind, e.g. relaxation and stress, through their impact on the autonomic nervous system. This study intended to investigate differential effects of four yogic breathing techniq [...]

by Yang Zhang  , Jiawen Chen  , Xiaowen Hu  , Wei Zhao  , Dirk J. Broer  and Guofu Zhou

Received: 17 August 2021;  Published: 01 November 2021;  doi: 10.21926/rpm.2104044

The reverse mode polymer dispersed liquid crystal (PDLC) is an emerging smart window technology. Unlike traditional PDLCs, a reverse mode PDLC can be transparent and opaque in the absence and presence of an external electric field. This report provides a brief introduction to several reverse modes PDLC smart window technologies, focusing on polymer-stabilized liquid crystals (PSLCs). The systems based on electrohydrodynamic instability (EHDI) of liquid crystals have also been discussed. The working principles, mode [...]

by Shaikha Al-Ballam  , Hamidreza Karami  and Deepak Devegowda

Received: 27 September 2022;  Published: 14 November 2022;  doi: 10.21926/jept.2204036

Electrical Submersible Pumps (ESPs) are one of the most widely used artificial lift methods in the petroleum industry. However, ESP failures are unanticipated and common occurrences with significant financial impacts for the operators. Analysis of the ESP performance and failures are essential in its design and optimization. This paper presents a statistical approach for diagnosing and evaluating the root causes of ESP failures. The analysis is based on the field data gathered from the surface and downhole ESP moni [...]

by Sydney Katras  , Dejian Ma  , Ayman al Dayeh  and David Tipton

Received: 31 March 2021;  Published: 12 August 2021;  doi: 10.21926/rpm.2103034

Bisphenol A (BPA) is a widely used synthetic compound that has been identified as an endocrine disruptor. It has been linked to adverse health effects such as developmental defects, infertility in both men and women, cardiovascular disease, and obesity. There has been increased interest in BPA’s effects on the developing fetus and data has revealed that doses below the presumed safe dose can produce harmful effects. Orthodontic clear aligner therapy is a popular treatment modality that involves the patient we [...]

by Myllena R. Rodrigues dos Santos  , Daniela B. Battaglia Hirata  and Joelise A.F. de Alencar Figueira Angelotti

Received: 16 February 2022;  Published: 07 May 2022;  doi: 10.21926/cr.2202013

Enzymes are extensively used in biotechnological processes in several areas of industry. They are sustainable and safe, and their specificity is another characteristic that improves the performance in the process. Among enzymes, lipase is relevant due to the ability to play different roles in the industry and the possibility of collecting them from microbial sources that are found in industrial residues. This can reduce the costs of enzyme production. In relation to that, lipase immobilization is an interesting pro [...]

by Joshua C. Brown  and Jessica L. Broadway

Received: 01 December 2020;  Published: 20 April 2021;  doi: 10.21926/obm.neurobiol.2102091

Lamotrigine is generally accepted as a well-tolerated medication with few cognitive side effects. Here, we report a case of a 62-year old female with a severe, rapidly progressive dementia-like process which was completely reversed after reduction of lamotrigine. Associated findings included hyperreflexia with clonus, ataxia, Wernicke-like dysphasia, global cognitive impairment, burst suppression on electroencephalogram (EEG), and bilateral parietal hypo-metabolism on fluorodeoxyglucose-Positron Emission Tomography [...]

by Mohammad Harun-Ur-Rashid  and Abu Bin Imran

Received: 30 June 2024;  Published: 30 September 2024;  doi: 10.21926/rpm.2403024

Emerging Trends in Engineering Polymers signify a pivotal transformation in material engineering, marking a departure from traditional materials towards innovative, multifunctional, and sustainable polymers. This review delineates the forefront of advancements in polymer materials, including high-performance, bio-based, biodegradable, innovative, and functional polymers. Highlighting their enhanced mechanical properties, thermal stability, and chemical resistance showcases these materials' pivotal role in driving t [...]

by Francesco E. Negro  and Francesco V. Marino

Received: 26 April 2021;  Published: 07 November 2021;  doi: 10.21926/obm.icm.2104045

The 19th century saw an explosion of serious epidemic diseases, such as smallpox and scarlet fever, which led to the development of an alternative system of medicine called homeopathy. Under this system, S. Hahnemann developed a rigorous methodology based on repeated observations on the field, leading to successful results. The aim of this work is to depict the birth and evolution of his thought. The correct understanding and application of this methodology became the reference model for subsequent generations of h [...]

by Patricia L. Gerbarg  , Richard P. Brown  , Chris C. Streeter  , Martin Katzman  and Monica Vermani

Received: 10 April 2019;  Published: 12 July 2019;  doi: 10.21926/obm.icm.1903045

Does compassion itself benefit the healing process or does the activation of neurophysiological processes, from which the experience of compassion arises, trigger a cascade of physical and psychological changes that support health and well-being? Exploration of the neurological substrates of compassion reveals multiple healing pathways that can be activated by mind-body practices. Furthermore, these pathways affect physical health, emotion regulation, and how we perceive and relate to others. Physiological states a [...]