Investigation of Managing Effective and Efficient Cell Phone Reverse Logistics

There are many factors influencing the sustainability of Closed-Loop Supply Chain (CLSC) operations in the cell phone industry. This research aims to identify theses factors which directly have a great impact on unused cell phone returns in order to provide a better understanding of implementing effective and efficient reverse logistics in the cell phone industry. In particular, the current situation of the cell phone reverse logistics in USA, Europe and China would be discussed. Data and information were collected through semi-structured interviews and questionnaire surveys, in order to anaylse the process flows in the supply chain. The key findings include the demonstration of the current situation of using cell phones in China and attitudes towards the management of the cell phone reverse logistics market. In addition, the constructive suggestions and suitable solutions for the Chinese government, manufacturers and other related stakeholders would be provided in this research. These are theoretical and practical supports for academics and companies to understand the handling of unused cell phones. Simultaneously, they assist companies in identifying and positioning themselves in the CLSC in order to define their direction for sustainable development in the long-term

Understanding the Passivation Mechanisms and Opto-Electronic Spectral Response in Methylammonium Lead Halide Perovskite Single Crystals

Attaining control over the surface traps in halide perovskites is critical for the tunability of ultimate device characteristics. Here, we present a study on the modulation of photophysical properties, surface traps, and recombination in MAPbI(3) single crystals (MSCs) with methylamine (MA) vapor surface treatment. Transient photoluminescence spectroscopy in conjunction with density functional theory calculations reveals that nonradiative recombination related to Pb2+ becomes mitigated after MA vaporing while radiative recombination via bimolecular path tends to increase, which originates from the passivation of Pb ions with the Lewis base nitrogen in MA. In contrast to the broad photoresponse in the pristine MSC photodiodes, application of MA surface treatments leads to a spectral narrowing effect (SNE) in MSCs with the response peak width</p

Phylogenetic and molecular characterization of coxsackievirus A24 variant isolates from a 2010 acute hemorrhagic conjunctivitis outbreak in Guangdong, China

<p>Abstract</p> <p>Background</p> <p>Acute hemorrhagic conjunctivitis is a common disease in China. As a notifiable disease, cases are registered by ophthalmologists on the AHC surveillance system. An AHC outbreak caused by CA24v was observed in Guangdong Province in 2007 by the National Disease Supervision Information Management System. Three years later, a larger outbreak occurred in Guangdong during the August-October period (2010). To characterize the outbreak and compare the genetic diversity of CA24v, which was determined to be the cause of the outbreak, the epidemiology and the molecular characterization of CA24v were analyzed in this study.</p> <p>Results</p> <p>A total of 69,635 cases were reported in the outbreak. 73.5% of index cases originated from students, children in kindergarten and factory workers, with the ≦ 9 age group at the highest risk. The male to female ratio was 1.84:1 among 0-19 years. 56 conjunctival swabs were collected to identify the causative agent from five cities with the AHC outbreak. 30 virus strains were isolated, and two of the genomes had the highest identity values (95.8%) with CA24v genomes. Four CA24v genotypes were identified by phylogenetic analysis for the VP1 and 3C regions. CA24v which caused the outbreak belonged to genotype IV. Furthermore, full nucleotide sequences for four representative isolates in 2010 and 2007 were determined and compared. 20 aa mutations, two nt insertions and one nt deletion were observed in the open reading frame, with 5'- and 3'- UTR respectively between them.</p> <p>Conclusions</p> <p>CA24v was determined to be the pathogen causing the outbreak and belongs to genotype IV. VP1 is more informative than 3C^Profor describing molecular epidemiology and we hypothesize that accumulative mutations may have promoted the outbreak.</p

Association between abnormal plasma metabolism and brain atrophy in alcohol-dependent patients

ObjectiveIn this study, we aimed to characterize the plasma metabolic profiles of brain atrophy and alcohol dependence (s) and to identify the underlying pathogenesis of brain atrophy related to alcohol dependence.MethodsWe acquired the plasma samples of alcohol-dependent patients and performed non-targeted metabolomic profiling analysis to identify alterations of key metabolites in the plasma of BA-ADPs. Machine learning algorithms and bioinformatic analysis were also used to identify predictive biomarkers and investigate their possible roles in brain atrophy related to alcohol dependence.ResultsA total of 26 plasma metabolites were significantly altered in the BA-ADPs group when compared with a group featuring alcohol-dependent patients without brain atrophy (NBA-ADPs). Nine of these differential metabolites were further identified as potential biomarkers for BA-ADPs. Receiver operating characteristic curves demonstrated that these potential biomarkers exhibited good sensitivity and specificity for distinguishing BA-ADPs from NBA-ADPs. Moreover, metabolic pathway analysis suggested that glycerophospholipid metabolism may be highly involved in the pathogenesis of alcohol-induced brain atrophy.ConclusionThis plasma metabolomic study provides a valuable resource for enhancing our understanding of alcohol-induced brain atrophy and offers potential targets for therapeutic intervention

Enhanced Photoelectrochemical Detection of Bioaffinity Reactions by Vertically Oriented Au Nanobranches Complexed with a Biotinylated Polythiophene Derivative

Four nanostructured Au electrodes were prepared by a simple and templateless electrochemical deposition technique. After complexing with a biotinylated polythiophene derivative (PTBL), photocurrent generation and performance of PTBL/Au-nanostructured electrodes as photoelectrochemical biosensors were investigated. Among these four nanostructured Au electrodes, vertically oriented nanobranches on the electrode significantly improved the photoelectric conversion, because the vertically oriented nanostructures not only benefit light harvesting but also the transfer of the photogenerated charge carriers. Owing to this advantaged nanostructure, the PTBL/Au-nanobranch electrode showed higher sensitivity and faster response times in the photoelectrochemical detection of a streptavidin-biotin affinity reaction compared to a PTBL/Au-nanoparticle electrode

Investigation of Managing Effective and Efficient Cell Phone Reverse Logistics

There are many factors influencing the sustainability of Closed-Loop Supply Chain (CLSC) operations in the cell phone industry. This research aims to identify theses factors which directly have a great impact on unused cell phone returns in order to provide a better understanding of implementing effective and efficient reverse logistics in the cell phone industry. In particular, the current situation of the cell phone reverse logistics in USA, Europe and China would be discussed. Data and information were collected through semi-structured interviews and questionnaire surveys, in order to anaylse the process flows in the supply chain. The key findings include the demonstration of the current situation of using cell phones in China and attitudes towards the management of the cell phone reverse logistics market. In addition, the constructive suggestions and suitable solutions for the Chinese government, manufacturers and other related stakeholders would be provided in this research. These are theoretical and practical supports for academics and companies to understand the handling of unused cell phones. Simultaneously, they assist companies in identifying and positioning themselves in the CLSC in order to define their direction for sustainable development in the long-term

Understanding the Impact of Bismuth Heterovalent Doping on the Structural and Photophysical Properties of CH3NH3PbBr3 Halide Perovskite Crystals with Near-IR Photoluminescence

A comprehensive study unveiling the impact of heterovalent doping with Bi3+ on the structural, semiconductive, and photoluminescent properties of a single crystal of lead halide perovskites (CH3NH3PbBr3) is presented. As indicated by single-crystal XRD, a perfect cubic structure in Bi3+-doped CH3NH3PbBr3 crystals is maintained in association with a slight lattice contraction. Time-resolved and power-dependent photoluminescence (PL) spectroscopy illustrates a progressively quenched PL of visible emission, alongside the appearance of a new PL signal in the near-infrared (NIR) regime, which is likely to be due to energy transfer to the Bi sites. These optical characteristics indicate the role of Bi-3 dopants as nonradiative recombination centers, which explains the observed transition from bimolecular recombination in pristine CH3NH3PbBr3 to a dominant trap-assisted monomolecular recombination with Bi3+ doping. Electrically, it is found that the mobility in pristine perovskite crystals can be boosted with a low Bi3+ concentration, which may be related to a trap-filling mechanism. Aided by temperature (7)-dependent measurements, two temperature regimes are observed in association with different activation energies (E-a) for electrical conductivity. The reduction of E-a at lower T may be ascribed to suppression of ionic conduction induced by doping. The modified electrical properties and NIR emission with the control of Bi3+ concentration shed light on the opportunity to apply heterovalent doping of perovskite single crystals for NIR optoelectronic applications

Localization of receptor site on insect sodium channel for depressant β-toxin BmK IT2.

BACKGROUND: BmK IT2 is regarded as a receptor site-4 modulator of sodium channels with depressant insect toxicity. It also displays anti-nociceptive and anti-convulsant activities in rat models. In this study, the potency and efficacy of BmK IT2 were for the first time assessed and compared among four sodium channel isoforms expressed in Xenopus oocytes. Combined with molecular approach, the receptor site of BmK IT2 was further localized. PRINCIPAL FINDINGS: 2 µM BmK IT2 strongly shifted the activation of DmNa(v)1, the sodium channel from Drosophila, to more hyperpolarized potentials; whereas it hardly affected the gating properties of rNa(v)1.2, rNa(v)1.3 and mNa(v)1.6, three mammalian central neuronal sodium channel subtypes. (1) Mutations of Glu(896), Leu(899), Gly(904) in extracellular loop Domain II S3-S4 of DmNa(v)1 abolished the functional action of BmK IT2. (2) BmK IT2-preference for DmNa(v)1 could be conferred by Domain III. Analysis of subsequent DmNa(v)1 mutants highlighted the residues in Domain III pore loop, esp. Ile(1529) was critical for recognition and binding of BmK IT2. CONCLUSIONS/SIGNIFICANCE: In this study, BmK IT2 displayed total insect-selectivity. Two binding regions, comprising domains II and III of DmNa(v)1, play separated but indispensable roles in the interaction with BmK IT2. The insensitivity of Na(v)1.2, Na(v)1.3 and Na(v)1.6 to BmK IT2 suggests other isoforms or mechanism might be involved in the suppressive activity of BmK IT2 in rat pathological models

Cathode interfacial layer-free all small-molecule solar cells with efficiency over 12%

While nonfullerene small-molecule solar cells (NF-SMSCs) have relatively inferior performance compared with nonfullerene polymer solar cells, their performance is improving. In this work, a weak crystalline molecular donor BSFTR, was designed and synthesized to achieve efficient NF-SMSCs. By blending with a strong crystalline acceptor NBDTP-F-out, BSFTR achieves a well-intermixed blending morphology, which favors the formation of efficient charge percolation pathways with suppressed recombination. The BSFTR:NBDTP-F-out device obtains a power-conversion efficiency (PCE) of approximately 11.97% by achieving an efficient cathode interfacial layer (CIL)-free device that delivers an even higher PCE of 12.3%, which ranks among the top values for the reported NF-SMSCs. This work provides a simple solution for achieving high-performance NF-SMSCs by identifying the key factors for designing efficient, cost-saving, mass production-favorable CIL-free organic photovoltaic devices