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The purpose of this paper is to study the mechanism of efficient sputum excretion from the distal lung by using a tessellationally distal lung model with alveolar pores.

First, a two-dimensional tessellational composite structure of the bronchus, alveoli and alveolar pores (Kohn pore) is constructed with the tessellational splitting and fusion of regular hexagonal elements. Then, the level set method is used to study the effects of alveolar pores and their sizes, expiratory cycles and respiratory intensity.

The existence of alveolar pores is the prerequisite for sputum excretion, and there is an optimal size of alveolar pores for sputum excretion. Strong asymmetric respiration can break the reversibility of the flow at a low Reynolds number and causes significant net displacement of sputum. The expiratory cycle is negatively correlated with the net displacement of sputum. The respiratory intensity is positively correlated with the net displacement of sputum.

This research is helpful for understanding the complex sputum excretion process in diseases, such as pneumonia, and developing corresponding adjuvant therapy.

This study aims to perform flow simulations inside the acinus with fine alveolar pores (Kohn pores) using hexagonal cells and bottom-up geometric modeling, which enabled the elimination of invalid voids using previous top-bottom methods and spherical or circular cells.

Regular hexagonal cells were used to construct alveoli with no gaps via tessellation. Some hexagonal cells were fused to eliminate the inner boundaries to represent the structure of the bronchial tree. For the remaining hexagonal cells, the side lengths of the shared walls were adjusted to construct alveolar pores. Periodic moving boundaries with the same phase were set for all walls to describe synchronous contraction and expansion of the bronchi and alveoli.

More realistic flow characteristics in the distal lung were obtained. The effects of pore size and the mechanism of auxiliary ventilation of alveolar pores were revealed.

To the best of the authors’ knowledge, this is the first numerical simulation study on the function of multiple alveolar pores at the level of pulmonary acini, which will be helpful for simulating the dynamic process of cough and sputum excretion in the future.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

The purpose of the current study is to explain best practices for attempting humor in the workplace. Research on humor in the workplace has emphasized the use of leader humor but has neglected to provide guidance on how to successfully use humor. This is an important gap because unsuccessful humor attempts are associated with lowered status and disruptive behavior.

This paper summarizes three types of humor theories (i.e. cognitive, social and contextual) and derives principles from these theories that can be applied to improve humor success. Then, the authors apply the understanding of humor to workplace applications, providing suggestions for future empirical research inferred from the humor theories.

Humor attempts are most likely to land (i.e. invoke mirth) when they include a benign violation of mental schemas, societal norms or other expectations or when humor evokes shared feelings of benign superiority in the audience. Humor is less effective in goal-directed situations. Mirth is expected to increase group cohesion, leader trust and organizational identification and mitigate the effects of job stressors. Finally, employee learning and development activities (e.g. onboarding, training) seem like a good place to use humor to facilitate cognitive flexibility.

These suggestions from across psychological disciplines are synthesized to inform best practices for leader humor.

The aim of this study is a semantic comparative analysis between the current pandemic and the Spanish flu. It is based on a bilingual terminological perspective oriented to evaluate and compare the terms used to describe and communicate the pandemic's issues both to biomedical experts and to a non-specialist public.

The analysis carried out is a terminological comparative investigation performed on two corpora, the first containing scientific English articles, the second Italian national newspapers' issues on two pandemics, the Spanish flu and the current Covid-19 disease, towards the detection of semantic similarities and differences among them through the implementation of computational tasks and corpus linguistics methodologies.

Given the cross-fielding representativeness of terms, and their relevance within specific historical eras, our study is conducted both on a synchronic and on a diachronic level to discover the common lexical usages in the dissemination of the pandemic issues.

The study presents the extraction of the main representative terms about two pandemics and their usages to share news about their trends among the population and the integration of a topic modeling detection procedure to discover some of the main categories representing the lexicon of the pandemics with reference to a list of classes created by external thesauri and ontologies on pandemics. As a result, a detailed overview of the discrepancies, as well as similarities, retrieved in two historical corpora dealing with a common subject, i.e. the pandemics' terminology, is provided.

Chest wall reconstruction of large oncological defects following resection is challenging. Traditional management involves the use of different materials that surgeons creatively shape intraoperatively to restore the excised anatomy. This is time-consuming, difficult to mould into shape and causes some complications such as dislocation or paradoxical movement. This study aims to present the development and clinical implantation of a novel custom-made three-dimensional (3D) laser melting titanium alloy implant that reconstructs a large chest wall resection and maintains the integrity of the thoracic cage.

The whole development process of the novel implant is described: design specifications, computed tomography (CT) scan manipulation, 3D computer-assisted design (CAD), rapid prototyping, final manufacture and clinical implantation. A multidisciplinary collaboration in between engineers and surgeons guided the iterative design process.

The implant provided excellent aesthetical and functional results. The virtual planning and production of the implant prior to surgery reduced surgery time and uncertainty. It also improved safety and accuracy. The implant sited nicely on the patient anatomy after resection following the virtual plan. At six months following implantation, there were no implant-related complications of pain, infection, dislocation or paradoxical movement. This technique offered a fast lead-time for implant production, which is crucial for oncological treatment.

More cases and a long-term follow-up are needed to confirm and quantify the benefits of this procedure; further research is also required to design a solution that better mimics the chest wall biomechanics while preventing implant complications.

The authors present a novel custom thoracic implant that provided a satisfactory reconstruction of a large chest wall defect, developed and implanted within three weeks to address a fast-growing chondrosarcoma. Furthermore, the authors describe its development process in detail as a design guideline, discussing potential improvements and critical design considerations so that this study can be replicated for future cases.

The purpose of this paper is to develop an automatic control system for mechanical ventilation therapy based on the open lung concept (OLC) using artificial intelligence. In addition, mean arterial blood pressure (MAP) is stabilized by means of a decoupling controller with automated noradrenaline (NA) dosage to ensure adequate systemic perfusion during ventilation therapy for patients with acute respiratory distress syndrome (ARDS).

The aim is to develop an automatic control system for mechanical ventilation therapy based on the OLC using artificial intelligence. In addition, MAP is stabilized by means of a decoupling controller with automated NA dosage to ensure adequate systemic perfusion during ventilation therapy for patients with ARDS.

This innovative closed-loop mechanical ventilation system leads to a significant improvement in oxygenation, regulates end-tidal carbon dioxide for appropriate gas exchange and stabilizes MAP to guarantee proper systemic perfusion during the ventilation therapy.

Currently, this automatic ventilation system based on the OLC can only be applied in animal trials; for clinical use, such a system generally requires a mechanical ventilator and sensors with medical approval for humans.

For implementation of a closed-loop ventilation system, reliable signals from the sensors are a prerequisite for successful application.

The experiment with porcine dynamics demonstrates the feasibility and usefulness of this automatic closed-loop ventilation therapy, with hemodynamic control for severe ARDS. Moreover, this pilot study validated a new algorithm for implementation of the OLC, whereby all control objectives are fulfilled during the ventilation therapy with adequate hemodynamic control of patients with ARDS.

Fenugreek (Trigonella foenum-graecum) leaves have received an enormous demand due to their uses in traditional Indian preparations. It is a green leafy vegetable that is highly perishable in nature, due to high respiration rate; consequently, sensory as well as nutrient loss occurs at a very high rate. The aim of this research was to enhance the shelf life of fresh fenugreek leaves under modified atmosphere and determine the effect of different physiochemical parameters on storability of fenugreek leaves.

Fresh fenugreek leaves were stored in polypropylene (PP) film package under four different treatments, viz., T1: perforated (one perforation), T2: perforated (two perforation, 0.3 mm each), T3: non-perforated and T4: control sample. The control samples were kept in packages under ambient conditions. All packed samples were stored at 15°C temperature and 75 per cent relative humidity (RH). The quality was determined on the basis of retention of pigments, flavonoids, antioxidants, ascorbic acid and total phenols. The sensory evaluation of the stored samples was also carried out at regular intervals.

The results of this study indicated that the quality of fresh fenugreek leaves in PP (34 μm) non-perforated package (T3) stored at 15°C and 75 per cent RH was superior to those packed under other treatments on the basis of color retention, β-carotene, ascorbic acid, 2,2-diphenyl-1-picrylhydrazyl, total phenols and overall acceptability. The produce could be safely stored for 9 days without any adverse effect on bioactive compounds.

Factors leading to deterioration of quality of fresh fenugreek leaves like pigments and phenolic content were largely influenced by in-pack gaseous atmosphere inside the polymeric film packages. Modified atmosphere packaging with different treatments for enhancing shelf life and retention of bioactive compound of fenugreek was carried out in the work.

The paper aims to form system dynamics modeling in introduced in conjunction with econometric analysis and planned scenario analysis which will uniquely structure the process whereby the ex ante capital values of the prime retail real estate sector.

The integrated system dynamics model investigates the structural factors affecting a unique expectation‐centered capital value (CV) formation of the prime retail real estate sector, through system dynamics modeling, econometric analysis , and the analysis of planned scenarios. This model extends beyond the usual lags and time line aspect of the price discovery process. The retail real estate sector is investigated within the Singapore context, as this sector changes dynamically and non‐linearly in relation to rental, cost and general demand expectations and to exogenous shocks like the Severe Advanced Respiratory Syndrome (SARS) outbreak. These macroeconomic factors are introduced to investigate their impact on retail space CVs through sensitivity analysis, during the simulation period of 20 quarters from the zero reference quarter (2Q2002).

The paper finds that simulation runs of the expectations‐centered system dynamics model are based on three scenarios. Sensitivity analysis is conducted for each scenario. Optimistic scenarios' CVs are lower than those of the likely scenario, owing to developers forming excessively high expectations that cannot be met by the actual rental levels. Pessimistic scenarios' CVs are highest. Based on bounded logic and the conditions for all scenarios, there are huge differences in expectations resulting in a large disparity in the endogenous CVs. Low actual rents are primarily due to poor informational efficiency, as the prime retail real estate sector is not transparent enough, and that many transactions are privately closed. Expectations cannot be met as the market information is not disseminated extensively through the agents and players. The scenarios clearly highlight the problem of informational non‐availability in the sector. The main policy implication is a need for a more transparent system of sharing rental and pricing information for the retail real estate sector, which is meaningful for real estate developers, investors and urban planners to sustain the retail real estate sector's viability.

This paper takes system dynamics modeling to the next level of incorporating econometric analysis, to estimate the sensitivity of retail rent to cost and the change in retail rent, for effectively structuring the dynamic process whereby the ex ante CVs of the prime retail sector in Singapore are formed and assessed, through a unique and rigorous expectations‐centered system dynamics model of rents, cost, retail stock, general demand and exogenous factors.

The outbreak of Severe Acute Respiratory Syndrome (SARS) in Asia and North America has raised much concern from all angles and reflections on nowadays living environment that resulted in public health, especially the high−density urban residential complexes. The so−called community infection at Amoy Gardens apartment in Hong Kong was such a case that is worth further study. However, under the trends of globalization and sustainable development, SARS could be the first alert of unknown outbreak−type fatal epidemic to the coming biomedicine age.

Main findings of the investigation in Amoy Gardens by the Department of Health, Hong Kong, which has been mostly corroborated by World Health Organization (WHO), pointed that environmental factors played a major role in this outbreak. They are, in fact, related to community design, building design and facility management. In this respect, open building theory is conceived of ideas for solution. Three directions are discussed in this study: 1) “territorial depth” at urban tissue level and building level, 2) utility lines at building level and infill level, and 3) space layout by zoning at building level.

In conclusion, design principles for new buildings are suggested; (1) Creating territorial depths in urban tissue and building complex by hierarchical circulations so as to separate people's daily movement and reduce unnecessary human contacts. In addition, the deeper territory expands, the fewer the dwelling units will be preferred. (2) Planning unit space layout with envelope zone following fluid dynamics and solar control physics so as to avoid gaseous infection to people living in the neighborhood among multi−story buildings. (3) Constructing buildings with open−system interfaces between building level and infill level or between infill elements themselves, so that stopgap renovations could easily be done. (4) Separating service lines between building level and infill level. And locating maintenance shafts at accessible public space