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Green roofs are strategies for the ecological intensification of cities and a measure of meeting some of the sustainable development goals (SDGs). They have widely been adopted as an adaptation strategy against an urban heat island (UHI). However, they are conventionally soil-based making it difficult and expensive to adopt as a strategy for greening existing buildings (GEB). This paper, therefore, develops a novel green roof system using climbers for thermal-radiative performance. The paper explores the vitality of climbing species as a nature-based strategy for GEB, and for the ecological improvement of the predominantly used cool roofs in sub-Saharan Africa (SSA).

Simulation for the same building Kejetia Central Market (KCM) Redevelopment; the existing aluminium roof (AL), soil-based extensive green roof (GR1) and the proposed green roof using climbing plants (GR2) were performed using ENVI-met. The AL and GR1 were developed as reference models to evaluate and compare thermal-radiative performance of the conceptual model (GR2). The long wave radiation emission (Q_lw), mean radiant temperature (MRT) and outdoor air temperature (T_a) of all three roofing systems were simulated under clear sky conditions to assess the performance and plant vitality considering water access, leaf temperature (T_f) and latent heat flux (LE₀) of GR1 and GR2.

There was no short wave radiation (Q_sw) absorption at the GR2 substrate since the climbers have no underlying soil mass, recording daily mean average Q_lw emission of 435.17 Wm⁻². The soil of GR1, however, absorbed Q_sw of 390.11 Wm⁻² and a Q_lw emission of 16.20 wm⁻² higher than the GR2. The AL recorded the lowest Q_lw value of 75.43 Wm⁻². Also, the stomatal resistance (r_s) was higher in GR1 while GR2 recorded a higher average mean transpiration flux of 0.03 g/sm³. This indicates a higher chance of survival of the climbers. The T_a of GR2 recording 0.45°C lower than the GR1 could be a good UHI adaptation strategy.

No previous research on climbers for green roof systems was found for comparison, so the KCM project provided a unique confluence of dynamic events including the opportunity for block-scale impact assessment of the proposed GEB strategy. Notwithstanding, the single case study allowed a focussed exploration of the novel theory of redefining green roof systems with climbers. Moreover, the simulation was computationally expensive, and engaging multiple case studies were found to be overly exhaustive to arrive at the same meaningful conclusion. As a novelty, therefore, this research provides an alternative theory to the soil-based green roof phenomenon.

The thermal-radiative performance of green roofs could be improved with the use of climbers. The reduction of the intensity of UHI would lead to improved thermal comfort and building energy savings. Also, very little dependence on the volume of soil would require little structural load consideration thereby leading not only to cheaper green roof construction but their higher demand, adoption and implementation in SSA and other low-income economies of the global south.

The reduction of the consumption of topsoil and water for irrigation could avoid the negative environmental impacts of land degradation and pollution which have a deleterious impact on human health. This fulfils SDG 12 which seeks to ensure responsible consumption of products. This requires the need to advance the research for improvement and training of local built environment practitioners with new skills for installation to ensure social inclusiveness in the combat against the intractable forces of negative climate impacts.

Climbers are mostly known for green walls, but their innovative use for green roof systems has not been attempted and adopted; it could present a cost-effective strategy for the GEB. The proposed green roof system with climbers apart from becoming a successful strategy for UHI adaptation was also able to record an estimated 568% savings on topsoil consumption with an impact on the reduction of pollution from excavation. The research provides an initial insight into design options, potentials and limitations on the use of climbers for green roofs to guide future research and experimental verification.

Commercial buildings, which include office buildings, are one of the three major energy-consuming sectors, alongside industrial and transportation sectors. The vast increase in the number of buildings is a positive sign of the rapid development of Malaysia. However, most Malaysian government office buildings tend to consume energy inefficiently due to lack of energy optimization. Most of the previous studies focused on the performance of green buildings in fulfilling the green development guidelines. As such, it is essential to study the energy performance of existing government office buildings that were constructed before most energy-efficient standards were implemented to mitigate energy wastage due to the lack of energy optimization. This study aims to analyse the energy performance of existing non-green Malaysian government office buildings and the factors that influence building energy consumption, as well as to evaluate the efficacy of the existing energy conservation measures.

This study was conducted by a literature review and case study. The chosen buildings are six government office building blocks located in Kuala Lumpur, the capital city of Malaysia. In this study, a literature review has been conducted on the common factors affecting energy consumption in office buildings. The energy consumption data of the buildings were collected to calculate the building energy intensity (BEI). The BEI was compared to the MS1525:2019 and GBI benchmarks to evaluate energy performance. SketchUp software was utilized to illustrate the solar radiation and sun path diagram of the case study buildings. Finally, recommendations were derived for retrofit strategies based on non-design factors and passive design factors.

In typical government office buildings, the air-conditioning system consumed the most energy at 65.5%, followed by lighting system at 22.6%, and the remaining 11.9% was contributed by office appliances. The energy performance of the case study buildings is considered as satisfactory as the BEI did not exceed the MS1525:2019 benchmark of 200 kWh/m2/year. The E Block recorded the highest BEI of 183.12 kWh/m2/year in 2020 due to its north-east orientation which is exposed to the most solar radiation. Besides, E Block consists of rooms that can accommodate large number of occupants. As such, non-design factors which include higher occupancy rate and higher cooling demand due to high outdoor temperature leads to higher energy consumption. By considering passive design features such as building orientation and building envelope thermal properties, energy consumption can be reduced significantly.

This study provided a comprehensive insight into the energy performance of Malaysian government office buildings, which were constructed before the energy-efficient standards being introduced. By calculating the BEI of six government office buildings, it is found that the energy performance of the case study buildings fulfils the MS1525 benchmark, and that all their BEIs are below 200 kWh/m2/year. Malaysia's hot and humid climate significantly affects a building's cooling load, and it is found the air-conditioning system is the major energy consumer of Malaysian government office buildings. This study discusses the efficacy of the energy-saving measures implemented in the case study buildings to optimize energy consumption. Recommendations were derived based on the non-design factors and passive design factors that affected the energy consumption of the case study building. It is envisioned that this study can provide practical strategies for retrofit interventions to reduce energy consumption in Malaysian office buildings as well as for office buildings that are in a similar climate.

The purpose of this paper is to generate nitrogen-containing groups in the cotton fabric surface via low-temperature nitrogen plasma as an eco-friendly physical/zero-effluent process. This was done for rendering cotton dye-able with Acid Blue 284, which in fact does not have any direct affinity to fix on it.

Dyeing characteristics of the samples such as color strength (K/S), fastness properties to light, rubbing and perspiration and durability, as well as tensile strength, elongation at break, whiteness, weight loss and wettability in addition to zeta potential of the dyed samples, were determined and compared with untreated fabric. Confirmation and characterization of the plasma-treated samples via chemical modifications and zeta potential was also studied using Fourier transform infrared spectroscopy (FTIR) and Malvern Zetasizer instrumental analysis.

The obtained results of the plasma-treated fabric reflect the following findings: FTIR results indicate the formation of nitrogen-containing groups on cotton fabrics; notable enhancement in the fabric wettability, zeta potential to more positive values and improvement in the dyeability and overall fastness properties of treated cotton fabrics in comparison with untreated fabric; the tensile strength, elongation at break, whiteness and weight % of the plasma treated fabrics are lower than that untreated one; and the durability of the plasma treated fabric decreased with increasing the number of washing cycles.

The novelty addressed here is rendering cotton fabrics dye-able with acid dye via the creation of new cationic nitrogen-containing groups on their surface via nitrogen plasma treatment as an eco-friendly and efficient tool with a physical/zero-effluent process.

We enquire whether short-time work (STW) avoids firings as intended by policymakers and is associated with unintended side effects by subsidising some establishments and locking in some employees. Additionally, where it was feasible, establishments used working from home (WFH) to continue working without risking an increase in COVID-19 infections and allowing employed parents to care for children attending closed schools.

Using 21 waves of German high-frequency establishment panel data collected during the COVID-19 crisis, we investigate how STW and WFH are associated with hirings, firings, resignations and excess labour turnover (or churning).

Our results show the important influences of STW and working from home on employment dynamics during the pandemic. By means of STW, establishments are able to avoid an increase in involuntary layoffs and hiring decreases significantly. In contrast, WFH is associated with a rise in resignations, as can be expected from a theoretical perspective.

While most of the literature on STW and WFH is unrelated and remains descriptive, we consider them in conjunction and conduct panel data analyses. We apply data and methods that allow for the dynamic pattern of STW and working from home during the pandemic. Furthermore, our data include relevant establishment-level variables, such as the existence of a works council, employee qualifications, establishment size, the degree to which the establishment was affected by the COVID-19 crisis, industry affiliation and a wave indicator for the period the survey was conducted.

This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 10⁶, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.

This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.

This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.

This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.

The study explored whether an asynchronous short online course in mental health well-being and resilience for healthcare workers (HCWs) showed improved self-reported results among participants during the second wave of the COVID-19 pandemic.

A descriptive cross-sectional study evaluated the course outcomes using the 10-item Connor and Davison's Resilience Scale, the World Health Organization's WHO-five well-being index and self-developed questions. Data were collected via online questionnaires before and after course completion.

A total of 1 301 HCWs participated. The highest proportion of participants was from South Africa (SA) (93.7%) and females (78.7%). Analysed mean pre- and post-training scores showed increased scores in all five domains: knowledge, confidence in course outcomes, behaviour, resilience and well-being. Confidence in the course outcomes was the only common significant construct for both well-being and resilience. Mindfulness activities (β = 0.12, 95%CI [0.032, 0.213], p = 0.008) and self-care behaviours (β = 0.14, 95%CI [0.035, 0.241], p = 0.009) were significant predictors of participants' well-being. Coping mechanisms for stress (β = 0.12, 95%CI [0.036, 0.21], p = 0.006) and connecting with a social support network (β = 0.085, 95%CI [0.0007, 0.17], p = 0.048) were significant predictors of participants' resilience. Those working in the private sector, those working in clinical settings and those who were female showed significant associations with well-being and resilience.

The results are self-reported data which may be susceptible to social desirability and acquiescent effects. There are no guarantees that positive effects observed during this study are sustained over time. The study sample was selective in that it excluded those who did not consent for the use of their data and those who did not complete the course.

The research is noteworthy as literature shows that female HCWs tend to have worse mental health outcomes than males in the same field. Online learning can enable HCWs to conveniently access mental health education, accommodate their work commitments and explore topics that are potentially stigmatising.

Due to herbs and plants’ therapeutic properties and simplicity of availability in nature, humans have used them to treat a variety of maladies and diseases since ancient times. Later, as technology advanced, these plants and herbs gained significant relevance in some industries due to their suitable chemical composition, abundant availability and ease of access. Aegle marmelos is a species of plant that may be found in nature. Yet, little or very little literature was located on the coloration behavior of this plant’s leaves. This study aims to focus on the effect of different parameters on the extraction of colorant from Aegle marmelos leaves.

Some factors that affected on the extraction processes were examined and found to have significant impacts on the textile dyeing such as the initial dye concentration, extracted temperature, extracted bath pH and extracted time were all changed to see how they affected color extraction. The authors report a direct comparison between three heating methods, namely, microwave irradiation (MWI), ultrasonic waves (USW) and conventional heating (CH). The two kinetic models have been designed (pseudo-first and pseudo-second orders) in the context of these experiments to investigate the mechanism of the dyeing processes for fabrics under study. Also, the experimental data were analyzed according to the Langmuir and Freundlich isotherms.

From the result, it was discovered these characteristics were found to have a substantial effect on extraction efficiency. Temperature 90°C and 80°C when using CH and USW, respectively, while at 90% watt when using MWI, period 120 min when using CH as well as USW waves, while 40 min when using MWI, and pH 4, 5 and 10 for polyamide, wool and cotton, respectively, were the optimal extraction conditions. Also, the authors can say that wool gives a higher absorption than the other fabric. Additionally, MWI provided the best color strength (K/S) value, and homogeneity, at low temperatures reducing the energy and time consumed. The coloring follows the order: MWI > USW > CH. The adsorption isotherm of wool could be well fitted by Freundlich isotherm when applying CH and USW as a heating source, while it is well fitted by the Langmuir equation in the case of MWI. In the study, it was observed that the pseudo-first-order kinetic model fits better the experimental results of CH with a constant rate K₁ = −0.000171417 mg/g.min, while the pseudo-second-order kinetic model fits better the experimental results of absorption of both MWI (K2 = 38.14022572 mg/g.min) and USW (K₂ = 12.45343554 mg/g.min).

There is no research limitation for this work. Dye was extracted from Aegle marmelos leaves by applying three different heating sources (MWI, ultrasonic waves [USWW] and CH).

This work has practical applications for the textile industry. It is concluded that using Aegle marmelose leaves can be a possible alternative to extract dye from natural resource by applying new technology to save energy and time and can make the process greener.

Socially, it has a good impact on the ecosystem and global community because the extracted dye does not contain any carcinogenic materials.

The work is original and contains value-added products for the textile industry and other confederate fields.

Perceptions of employment histories are important insofar as they influence future job prospects. Critically, in light of the current pandemic, wherein many individuals are likely to have unanticipated employment gaps and/or temporary work experiences, this exploratory study aims to seek a better understanding of the signal associated with temporary employment histories, which is particularly germane to individuals' employment trajectories and a successful labour market recovery.

Drawing primarily on signalling theory and using a simulated hiring decision experiment, the authors examined the perceptions of temporary employment histories, as well as the period effect of COVID-19, a major exogenous event, on the attitudes of fictitious jobseekers with standard, temporary and unemployment histories.

The authors find that prior to COVID-19 unemployed and temporary-work candidates were perceived less favourably as compared to applicants employed in a permanent job. During the COVID-19 pandemic, assessments of jobseekers with temporary employment histories were less critical and the previously negative signal associated with job-hopping reversed. This study’s third wave of data, which were collected post-COVID, showed that such perceptions largely dissipated, with the exception for those with a history of temporary work with different employers.

The paper serves as a reminder to check, insofar as possible, preconceived biases of temporary employment histories to avoid potential attribution errors and miss otherwise capable candidates.

This paper makes a unique and timely contribution by focussing and examining the differential effect of economic climate, pivoted by the COVID-19 pandemic, on perceptions of temporary employment histories.

Within the context of the nonprofit resiliency framework, the authors use nonprofit functional expenses and contribution revenue to explore how the COVID-19 pandemic affected the ability of nonprofits in different subsectors to carry out their mission, as well as their ability to “pivot” fundraising strategies to integrate social media and digital engagement.

The authors use IRS form 990 return data for organizations with a year-end return that includes at least six months of COVID-19 impact (“Wave 1 Effects” period) and also have a prior-year return (“Business as Usual” period). The authors use Wilcoxon signed rank tests to examine whether there are differences in our variables of interest between the two periods.

While the majority of nonprofits in most subsectors experienced a significant decrease in program spending, fundraising spending and fundraising efficiency ratios between the two time periods, the authors found variation in the change in contribution revenue and fundraising ratio between the two periods between subsectors. The authors also find that the percentage of nonprofits able to “pivot” their fundraising strategies varies by subsector between 13.33 and 31.23%.

This paper provides new information regarding the pandemic's initial effect on nonprofit program and fundraising spending, the related contribution revenue and the ability of nonprofits to “pivot” fundraising to remote strategies. The authors propose a more robust fundraising efficiency measure and a new measure indicating a nonprofit's “ability to pivot” their fundraising strategy. The authors encourage future researchers to conduct further longitudinal studies to understand how these effects may continue or change.

Middle-aged and elderly users become an important group on short-video platforms, however, the research on determinants of their video-creating intention is limited. Based on lifespan development theories, this study examines the impact of aging experiences on their video-creating intention, considering internal generative motivations as mediators and age as a moderator.

To test this study’s hypotheses, survey data from 321 Chinese middle-aged and elderly short-video users were collected and partial least square-structural equation modelling (PLS-SEM) approach was used to analyze these data.

Middle-aged and elderly users' aging experiences of social loss and personal growth are positively related to their video-creating intention. Aging experiences (i.e. physical loss, social loss, and personal growth) are positively related to internal generative motivations (i.e. need to be needed and symbolic immortality), and need to be needed is positively related to video-creating intention. Via the mediation of need to be needed, physical loss and personal growth are indirectly positively related to video-creating intention. Personal growth strengthens the relationship between physical loss and symbolic immortality, but weakens the associations of social loss with need to be needed and symbolic immortality. Age weakens the relationship between symbolic immortality and video-creating intention.

This study is the first wave to introduce and integrate lifespan theories such as selective optimization with compensation model, socioemotional selectivity theory, and generativity theory to explore the impacts of aging experiences on middle-aged and elderly users' video-creating intention by considering generativity motivations as mediators and age as a moderator.