The effects of aerosols on precipitation and dimensions of subtropical clouds: a sensitivity study using a numerical cloud model

Numerical experiments were carried out using the Tel-Aviv University 2-D cloud model to investigate the effects of increased concentrations of Cloud Condensation Nuclei (CCN), giant CCN (GCCN) and Ice Nuclei (IN) on the development of precipitation and cloud structure in mixed-phase sub-tropical convective clouds. In order to differentiate between the contribution of the aerosols and the meteorology, all simulations were conducted with the same meteorological conditions. <P style='line-height: 20px;'> The results show that under the same meteorological conditions, polluted clouds (with high CCN concentrations) produce less precipitation than clean clouds (with low CCN concentrations), the initiation of precipitation is delayed and the lifetimes of the clouds are longer. GCCN enhance the total precipitation on the ground in polluted clouds but they have no noticeable effect on cleaner clouds. The increased rainfall due to GCCN is mainly a result of the increased graupel mass in the cloud, but it only partially offsets the decrease in rainfall due to pollution (increased CCN). The addition of more effective IN, such as mineral dust particles, reduces the total amount of precipitation on the ground. This reduction is more pronounced in clean clouds than in polluted ones. <P style='line-height: 20px;'> Polluted clouds reach higher altitudes and are wider than clean clouds and both produce wider clouds (anvils) when more IN are introduced. Since under the same vertical sounding the polluted clouds produce less rain, more water vapor is left aloft after the rain stops. In our simulations about 3.5 times more water evaporates after the rain stops from the polluted cloud as compared to the clean cloud. The implication is that much more water vapor is transported from lower levels to the mid troposphere under polluted conditions, something that should be considered in climate models

Concise Synthesis of the Antidepressive Drug Candidate GSK1360707 by a Highly Enantioselective Gold-Catalyzed Enyne Cycloisomerization Reaction

Out of depression: Indeed, no depressing results are obtained from a gold-catalyzed enyne cycloisomerization controlled by phosphoramidite ligands with TADDOL-related but acyclic backbones (see scheme; Cbz=benzyloxycarbonyl). The “triple-reuptake inhibitor” GSK1360707 was obtained in excellent yield and optical purity, therefore highlighting the relevance of asymmetric gold catalysis for practical applications

Supply Chain Management and Hypercompetition

Firms nowadays face significant challenges in their operating environments, which have been characterised in two different ways. From a strategic management perspective these environments are in a state of hypercompetition while from a logistics or supply chain perspective these environments require market responsiveness predicated upon agile supply chains. However, firms must also rely on many interorganizational relationships to ensure efficient and effective movements within their supply chains. This paper discusses the relationships among these concepts and proposes a research framework combining aspects of the hypercompetition and responsiveness and agility viewpoints

The effect of ambient scent on consumers' perception, emotions, and behaviour: A critical review

The effect of olfactory stimuli on consumer behaviour has received little attention in marketing and retailing literature compared to other atmospheric cues. Researchers report ambiguous findings and shortcomings of measurement approaches. Based on a critical literature review, a field experiment in a regional shopping mall investigates the effectiveness of ambient scent. Before-and-after surveys of randomly-selected shoppers in experimental and control groups were conducted and different experimental designs simulated. Those designs not controlling either extraneous variables or attitudinal differences between control and experimental group reveal a positive effect on factors operationalising mall perception and consumers&rsquo; emotions. The design controlling both sources of bias indicates no impact of ambient scent on the dependent variables. None of the behavioural variables were affected in any case. This paper questions prior findings on the effectiveness of ambient scent in a shopping mall environment and calls for more rigour in investigating the effectiveness of atmospheric stimuli in general

To the Detection of Bondline Flaws in Rubber/Metal Laminates a Comparison of the Sensitivity of Transverse and Lamb Waves

The use of adhesively-bonded structures is prevalent throughout the Navy since watertight rubber-to-metal bonds are required on many undersea systems including sonar transducers and electrical cables. In addition, adhesive bonds are used to transfer loads between rubber and metal adherends for limited structural applications. However, in each case the principal function of the adhesive bond is to provide watertight integrity for the bonded components in the hostile ocean environment where corrosion is of major concern

Evaluación económica a nivel experimental sobre diferentes variedades comerciales de arroz, en el Valle del Rio Fundación, Departamento del Magdalena.

En el primer semestre de 1985 se realizó en la zona del Valle del río Fundación, en la finca denominada San Diego, municipio de Aracataca, departamento del Magdalena un trabajo de investigación para, comparar económicamente las diferentes variedades comerciales de arroz, con el fín de determinar la más rentable. El diseño experimental fue bloques al azar con 4 replicaciones y 10 tratamientos por replicación; el tamaño de las parcelas fue de 8 metros de largo por 5 metros de ancho, con una distancia de siembra de un metro en cuadro. Se determinó un solo factor "variedad" a cinco niveles: variedad L (IR -22), variedad (ORYZICA-2), variedad --3 (CICA -4), -variedad 4 (ORYZICA-1), y variedad 5 (CICA-8); cada variedad representada por un testigo absoluto dentro del ensayo. Con base en el diseño experimental para nuestro análisis económico se escogieron las variedades comerciales de arroz, proyectando los costos a una hectárea. Los resultados obtenidos mostraron que la variedad más rentable, teniendo en cuenta el indicador de rentabilidad es la IR -22

Functional strengthening through synaptic scaling upon connectivity disruption in neuronal cultures

An elusive phenomenon in network neuroscience is the extent of neuronal activity remodeling upon damage. Here, we investigate the action of gradual synaptic blockade on the effective connectivity in cortical networks in vitro. We use two neuronal cultures configurations—one formed by about 130 neuronal aggregates and another one formed by about 600 individual neurons—and monitor their spontaneous activity upon progressive weakening of excitatory connectivity. We report that the effective connectivity in all cultures exhibits a first phase of transient strengthening followed by a second phase of steady deterioration. We quantify these phases by measuring GEFF, the global efficiency in processing network information. We term hyperefficiency the sudden strengthening of GEFF upon network deterioration, which increases by 20–50% depending on culture type. Relying on numerical simulations we reveal the role of synaptic scaling, an activity–dependent mechanism for synaptic plasticity, in counteracting the perturbative action, neatly reproducing the observed hyperefficiency. Our results demonstrate the importance of synaptic scaling as resilience mechanism. Author Summary Neuronal circuits exhibit homeostatic plasticity mechanisms to cope with perturbations or damage. A central mechanism is ‘synaptic scaling,’ a self-organized response in which the strength of neurons’ excitatory synapses is adjusted to compensate for activity variations. Here we present experiments in which the excitatory connectivity of in vitro cortical networks is progressively weakened through chemical action. The spontaneous activity and effective connectivity of the whole network is monitored as degradation progresses, and the capacity of the network for broad information communication is quantified through the global efficiency. We observed that the network responded to the perturbation by strengthening the effective connectivity, reaching a hyperefficient state for moderate perturbations. The study proves the importance of ‘synaptic scaling’ as a driver for functional reorganization and network-wide resilience

Reduction and Emergence in Bose-Einstein Condensates

A closer look at some proposed Gedanken-experiments on BECs promises to shed light on several aspects of reduction and emergence in physics. These include the relations between classical descriptions and different quantum treatments of macroscopic systems, and the emergence of new properties and even new objects as a result of spontaneous symmetry breaking