Two distinct fluorescent quantum clusters of gold starting from metallic nanoparticles by pH-dependent ligand etching

Two fluorescent quantum clusters of gold, namely Au25 and Au8, have been synthesized from mercaptosuccinic acid-protected gold nanoparticles of 4-5 nm core diameter by etching with excess glutathione. While etching at pH ~3 yielded Au25, that at pH 7-8 yielded Au8. This is the first report of the synthesis of two quantum clusters starting from a single precursor. This simple method makes it possible to synthesize well-defined clusters in gram quantities. Since these clusters are highly fluorescent and are highly biocompatible due to their low metallic content, they can be used for diagnostic applications

Hybrid resource optimization strategy in heterogeneous wireless networks

The future generation of heterogeneous wireless networks (HWNs) will combine various radio access technologies for connecting various mobile subscribers (MS) based on the quality of service (QoS) and wireless network parameters, connecting MS to the best possible wireless network (WN) has been a trending research topic in HWNs. Existing resource optimization methods are designed to meet the QoS of network criteria and user preferences are neglected. Very limited work is done for resource optimization considering user preferences. However, these models are designed considering multi-mode terminals (MMTs) running a single service at a time under a low-density network; as a result, cannot be adopted to run multiple services simultaneously and; thus, fail to meet current users’ service dynamics requirement. Further, fails to bring good tradeoffs between reducing interference and improving performance. In addressing the research problem this work introduced a hybrid resource optimization strategy (HROS) to reduce interference by establishing channel availability and enhancing resource utilization through game theory. The HROS proves the existence of nash equilibrium (NE) improves throughput by 16.32% and reduces collision by 26.16% over the existing resource optimization-based network selection (RONS) scheme

Mechanical, Mineralogical and Durability Properties of Pulverized Pond Ash Based Concrete

In recent decades, cement production and demand have significantly impacted the environment; enormous amounts of energy are required to produce cement. This led to a severe energy crisis in our country. In order to minimize the usage of cement and energy consumption in an eco-friendly manner, industrial waste materials with cementitious characteristics are drawn to attention. Hence, the study deals with the use of pulverized pond ash as a partial replacement for cement in concrete. The mix design was carried out for M 25 grade concrete by IS 10262-2019. Two significant mix proportions were prepared, namely, Conventional Concrete (CC) (100 % cement), and Pulverized Pond Ash Concrete (PPAC) (90 % cement and 10% pulverized pond ash). In this study, cylinder compressive strength, mineralogical analysis, sulphate resistance tests, sorptivity, and water absorption, were examined. The PPAC mix outperformed CC in compressive strength by 10.74 %, 13.09 %, and 13.66 % at 28, 56, and 90 days, respectively. At 28 days, ettringite peaks are minor, with both intensity and quantity increasing significantly by 56 and 90 days. The PPAC also showed higher residual compressive strength (1.08 %, 1.65 %, 2.32 %) and lower sorptivity (8.93 %, 10.14 %, 12.5 %) than CC at all ages. From the results, PPAC showed superior properties than CC at all ages suggesting for replacement of 10 % of cement with pond ash

Plasmodium falciparum-infected erythrocyte knob density is linked to the PfEMP1 variant expressed

Members of the clonally variant Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family mediate adhesion of infected erythrocytes (IEs) to vascular receptors. PfEMP1 expression is normally confined to nanoscale knob protrusions on the IE surface membrane. To investigate the relationship between the densities of these IE surface knobs and the PfEMP1 variant expressed, we used specific antibody panning to generate three sublines of the P. falciparum clone IT4, which expresses the PfEMP1 variants IT4VAR04, IT4VAR32b, and IT4VAR60. The knob density in each subline was then determined by atomic force microscopy (AFM) and scanning electron microscopy (SEM) and compared to PfEMP1 and knob-associated histidine-rich protein (KAHRP) expression. Selection for uniform expression of IT4VAR04 produced little change in knob density, compared to unselected IEs. In contrast, selection for IT4VAR32b expression increased knob density approximately 3-fold, whereas IEs selected for IT4VAR60 expression were essentially knobless. When IT4VAR60+ IEs were subsequently selected to express IT4VAR04 or IT4VAR32b, they again displayed low and high knob densities, respectively. All sublines expressed KAHRP regardless of the PfEMP1 expressed. Our study documents for the first time that knob density is related to the PfEMP1 variant expressed. This may reflect topological requirements to ensure optimal adhesive properties of the IEs