A general compartment‐based population balance model for particle coating and layered granulation

In this work, a general multidimensional population balance (PB) model is developed to predict the coating volume distribution on polydisperse particles as a function of time during particle coating in a paddle mixer. The model adopts a compartmental approach to account for coating variation caused by particle flow heterogeneity. Simulations show that for a realistic range of seed particle size polydispersity and coating mass applied, the coating volume distribution depends on the growth rate exponent and seed particle size distribute on, with the coating volume coefficient of variance (CoV) approaching an asymptotic value as the coating‐to‐particle volume ratio increases. These effects cannot be predicted by simpler one‐dimensional models. However, the full two‐dimensional PB and simpler one‐dimensional models such as Mann's equation do predict similar sensitivity of coating volume CoV to the variation in the compartment model parameters, i.e., to changes in the particle mixing behavior in the vessel. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

Better safe than sorry - Emergency knowledge and preparedness in the German population

Emergency situations require immediate reaction in order to mitigate their negative effects. Being prepared for an emergency entails having preparedness measures present. The present study investigated the impact of socio-demographic and emergency factors (i.e., experience, risk perception, perceived and objective emergency knowledge) on fire and medical emergency related preparedness. A telephone survey was conducted in a representative German sample (N = 2225). Results revealed that both objective and perceived knowledge increased the likelihood not only for adopting preparedness measures but also for their consideration. The impact of socio-demographic variables on preparedness varied among the respective preparedness items with a greater impact of collective factors (e.g. people in the household, children, marital status) as compared to individual factors like age and gender. The need for safety trainings and their repetition is discussed.     

Color–concept associations: A cross‐occupational and ‐cultural study and comparison

This study used a questionnaire survey to examine color–concept associations in two occupational groups from Hebei Province in China: steel workers (n = 139) and managerial staff (n = 74). The color stereotypes held by these two groups were also compared to those held by three other cultural groups studied elsewhere (Hong Kong Chinese, Yunnan Chinese, and Americans). The participants were presented with 16 concepts and asked to choose one of 10 colors to represent each concept. The chi‐square test results showed that each concept was significantly associated with at least one color. Both the steel workers and the managerial staff primarily associated green with “go” and “safe” and red with “stop” and “danger.” The cross‐group comparisons indicated that the steel workers and the managerial staff produced stronger color associations than those produced by the Yunnan Chinese and the Hong Kong Chinese subjects, but weaker than those produced by the US subjects. Our findings build on existing knowledge of population stereotypes for color–concept associations and provide guidelines for the design of color displays and products for global users. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 630–635, 2014     

Robustness of differentiation cascades with symmetric stem cell division

Stem cells (SCs) perform the task of maintaining tissue homeostasis by both self-renewal and differentiation. While it has been argued that SCs divide asymmetrically, there is also evidence that SCs undergo symmetric division. Symmetric SC division has been speculated to be key for expanding cell numbers in development and regeneration after injury. However, it might lead to uncontrolled growth and malignancies such as cancer. In order to explore the role of symmetric SC division, we propose a mathematical model of the effect of symmetric SC division on the robustness of a population regulated by a serial differentiation cascade and we show that this may lead to extinction of such population. We examine how the extinction likelihood depends on defining characteristics of the population such as the number of intermediate cell compartments. We show that longer differentiation cascades are more prone to extinction than systems with less intermediate compartments. Furthermore, we have analysed the possibility of mixed symmetric and asymmetric cell division against invasions by mutant invaders in order to find optimal architecture. Our results show that more robust populations are those with unfrequent symmetric behaviour.     

Future bottlenecks in international river basins: where transboundary institutions,population growth and hydrological variability intersect

Using global data, this article examines the nexus of transboundary flood events and future social vulnerability. Which international river basins are forecast to experience an increase in both hydrological variability and population in the future, but currently lack institutional provisions to deal with these shared events? Concentrations of elevated risk are found in several basins in Central Asia, Central America and Central Africa. The article ends by highlighting transboundary basins that merit further investigation and possibly additional institution building to reduce urban flood risk.     

城市树木致伤风险可视化评估：以武汉市 中山公园为例

城市中的树木能提供多种生态系统服务，但树木倒 伏、树枝坠落也可能致人伤害，评估城市树木风险能有效地预 防伤害发生、保障人身安全。但当前研究的评估维度多聚焦于 树木自身，对城市人群致伤可能性的考量较少。建构了风险严 重性、风险可能性和致伤潜力3个维度的城市树木致伤风险指 数(I UTIR)评估方法，以武汉市中山公园为例展开树木致伤风险 评估，并分析了树木自身风险、致伤潜力与致伤风险之间的空 间关系。研究发现：68.7%的区域中，树木自身风险与致伤潜 力之间的空间关系呈现正相关性，25.1%的区域呈现负相关 性。在此基础上，提出了预防树木致伤风险的管理建议。为公 园规划设计和树木风险管理策略提供参考，从而减弱树木致伤 风险对人体健康的影响。     

Single medium microbial fuel cell: Stainless steel and graphite electrode materials select bacterial communities resulting in opposite electrocatalytic activities

A graphite electrode and a stainless steel electrode immersed in exactly the same medium and polarised at the same potential were colonised by different microbial biofilms. This difference in electroactive microbial population leads stainless steel and graphite to become a microbial cathode and a microbial anode respectively. The results demonstrated that the electrode material can drive the electrocatalytic property of the biofilm opening perspectives for designing single medium MFC.This new discovery led to of the first demonstration of a “single medium MFC.” Such a single medium MFC designed with a graphite anode connected to a stainless steel cathode, both buried in marine sediments, produced 280 mA m^?2 at a voltage of 0.3 V for more than 2 weeks.     

Single passage in mouse organs enhances the survival and spread of Salmonella enterica

Intravenous inoculation of Salmonella enterica serovar Typhimurium into mice is a prime experimental model of invasive salmonellosis. The use of wild-type isogenic tagged strains (WITS) in this system has revealed that bacteria undergo independent bottlenecks in the liver and spleen before establishing a systemic infection. We recently showed that those bacteria that survived the bottleneck exhibited enhanced growth when transferred to naive mice. In this study, we set out to disentangle the components of this in vivo adaptation by inoculating mice with WITS grown either in vitro or in vivo. We developed an original method to estimate the replication and killing rates of bacteria from experimental data, which involved solving the probability-generating function of a non-homogeneous birth–death–immigration process. This revealed a low initial mortality in bacteria obtained from a donor animal. Next, an analysis of WITS distributions in the livers and spleens of recipient animals indicated that in vivo-passaged bacteria started spreading between organs earlier than in vitro-grown bacteria. These results further our understanding of the influence of passage in a host on the fitness and virulence of Salmonella enterica and represent an advance in the power of investigation on the patterns and mechanisms of host–pathogen interactions.     

Validating the moderating role of age in multi-perspective acceptance model of wearable healthcare technology

The recent trend of aging population, not to mention the unprecedented pandemic, draws great attention from the general public about health concerns. Since healthcare information technology is different from non-healthcare information technology, additional contexts should be properly incorporated into technology acceptance research to accurately identify influential factors affecting the acceptance of wearable healthcare technology. Thus, we selectively reconfigured factors from health, privacy, and socio-demographic contexts to formulate a health-aware acceptance model. Then, it was empirically analyzed using structural equation modeling. Based on the results, whereas privacy concerns were directly associated with intention to use wearable healthcare technology, health concerns were not. Moreover, age had a moderating effect on social influence and facilitating conditions. These findings suggest valuable insights that the adoption rate of healthcare technology is increased by 1) keeping personal information securely, 2) facilitating social interaction among users, and 3) offering intuitive user experience for elderly people.