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Surface vacancy engineering has emerged as a useful method for enhancing the performance of semiconductor nanocrystals (SNCs). Moreover, it is always anticipated to explore further synthesis mechanism and functional nanomaterials via overcoming kinetic energy barriers of multi-step reactions. Herein, we developed an effective surface-vacancy-engineering-initialized cation exchange (SVEICE) strategy to overcome the kinetic energy barriers of cation exchange reactions from ternary CuInX2 (X = S, Se) to Cu, In dual-doped binary CdX, or ZnX SNCs by precisely tailoring surface Cu and In vacancy identities. These dual-doped SNCs exhibited dual-doped-dependent optoelectronic properties unprecedentedly. Due to the good versatility, this strategy is expected to drive further progress of doped SNC synthesis, cation exchange, and surface vacancy engineering.

Background: Structural variations (SVs; defined as DNA variants ≥ 50 base pairs) have been associated with various complex human diseases. However, research to screen the whole genome for SVs predisposing to psoriasis is lacking. Objectives: To investigate the association of SVs and psoriasis. Methods: Using imputation, we performed a genome-wide screen of SVs on five independent cohorts with 45 386 participants from the Han Chinese population. Fine-mapping analysis, genetic interaction analysis and RNA expression analysis were conducted to explore the mechanism of SVs. Results: In total, we obtained 4535 SVs and identified two novel deletions [esv3608550, odds ratio (OR) 2·73 (P < 2·00 × 10–308); esv3608542, OR 0·47 (P = 7·40 × 10–28)] at 6q21·33 (major histocompatibility complex), one novel Alu element insertion [esv3607339; OR 1·22 (P = 1·18 × 10–35)] at 5q33·3 (IL12B) and confirmed one previously reported deletion [esv3587563; OR 1·30 (P = 9·52 × 10–60)] at 1q21·2 (late cornified envelope) for psoriasis. Fine-mapping analysis including single-nucleotide polymorphisms (SNPs) and small insertions/deletions revealed that esv3608550 and esv3608542 were independently associated with psoriasis, and a novel independent SNP [rs9378188; OR, 1·65 (P = 3·46 × 10–38)] was identified at 6q21·33. By genetic interaction analysis and RNA expression analysis, we speculate that the association of two deletions at 6q21·33 with psoriasis might relate to their influence on the expression of HLA-C. Conclusions: We have constructed the most comprehensive SV map for psoriasis thus far and enriched the genetic architecture and pathogenesis of psoriasis, and highlight the non-negligible impact of SVs on complex diseases.

Background: Structural variations (SVs; defined as DNA variants ≥ 50 base pairs) have been associated with various complex human diseases. However, research to screen the whole genome for SVs predisposing to psoriasis is lacking. Objectives: To investigate the association of SVs and psoriasis. Methods: Using imputation, we performed a genome-wide screen of SVs on five independent cohorts with 45 386 participants from the Han Chinese population. Fine-mapping analysis, genetic interaction analysis and RNA expression analysis were conducted to explore the mechanism of SVs. Results: In total, we obtained 4535 SVs and identified two novel deletions [esv3608550, odds ratio (OR) 2·73 (P < 2·00 × 10–308); esv3608542, OR 0·47 (P = 7·40 × 10–28)] at 6q21·33 (major histocompatibility complex), one novel Alu element insertion [esv3607339; OR 1·22 (P = 1·18 × 10–35)] at 5q33·3 (IL12B) and confirmed one previously reported deletion [esv3587563; OR 1·30 (P = 9·52 × 10–60)] at 1q21·2 (late cornified envelope) for psoriasis. Fine-mapping analysis including single-nucleotide polymorphisms (SNPs) and small insertions/deletions revealed that esv3608550 and esv3608542 were independently associated with psoriasis, and a novel independent SNP [rs9378188; OR, 1·65 (P = 3·46 × 10–38)] was identified at 6q21·33. By genetic interaction analysis and RNA expression analysis, we speculate that the association of two deletions at 6q21·33 with psoriasis might relate to their influence on the expression of HLA-C. Conclusions: We have constructed the most comprehensive SV map for psoriasis thus far and enriched the genetic architecture and pathogenesis of psoriasis, and highlight the non-negligible impact of SVs on complex diseases.

Hexagonal lyotropic liquid crystals (HLLC) with uniform pore size in the range of 1~5 nm are highly sought after as promising active separation layers of thin-film composite (TFC) membranes, which have been confirmed to be efficient for water purification. The potential interaction between an amphiphile-based HLLC layer and the substrate surface, however, has not been fully explored. In this research, hydrophilic and hydrophobic microporous polyvinylidene fluoride (PVDF) substrates were chosen, respectively, to prepare TFC membranes with the active layers templated from HLLC, consisting of dodecyl trimethylammonium bromide, water, and a mixture of poly (ethylene glycol) diacrylate and 2-hydroxyethyl methacrylate. The pore size of the active layer was found to decrease by about 1.6 Å compared to that of the free-standing HLLC after polymerization, but no significant difference was observable by using either hydrophilic or hydrophobic substrates (26.9 Å vs. 27.1 Å). The water flux of the TFC membrane with the hydrophobic substrate, however, was higher than that with the hydrophilic one. A further investigation confirmed that the increase in water flux originated from a much higher porosity was due to the synergistic effect of the hydrophilic HLLC nanoporous material and the hydrophobic substrate.

Ternary I-III-VI2 nanocrystals (NCs), such as AgInS2 and CuInS2, are garnering interest as heavy-metal-free materials for photovoltaics, luminescent solar concentrators, LEDs, and bioimaging. The origin of the emission and absorption properties in this class of NCs is still a subject of debate. Recent theoretical and experimental studies revealed that the characteristic Stokes-shifted and long-lived luminescence of stoichiometric CuInS2 NCs arises from the detailed structure of the valence band featuring two sublevels with different parity. The same valence band substructure is predicted to occur in AgInS2 NCs, yet no experimental confirmation is available to date. Here, we use complementary spectroscopic, spectro-electrochemical, and magneto-optical investigations as a function of temperature to investigate the band structure and the excitonic recombination mechanisms in stoichiometric AgInS2 NCs. Transient transmission measurements reveal the signatures of two subbands with opposite parity, and photoluminescence studies at cryogenic temperatures evidence a dark state emission due to enhanced exchange interaction, consistent with the behavior of stoichiometric CuInS2 NCs. Lowering the temperature as well as applying reducing electrochemical potentials further suppress electron trapping, which represents the main nonradiative channel for exciton decay, leading to nearly 100% emission efficiency.

Postsynaptic density (PSD) proteins have been implicated in the pathophysiology of neurodevelopmental and psychiatric disorders. Here, we present detailed clinical and genetic data for 20 patients with likely gene-disrupting mutations in TANC2-whose protein product interacts with multiple PSD proteins. Pediatric patients with disruptive mutations present with autism, intellectual disability, and delayed language and motor development. In addition to a variable degree of epilepsy and facial dysmorphism, we observe a pattern of more complex psychiatric dysfunction or behavioral problems in adult probands or carrier parents. Although this observation requires replication to establish statistical significance, it also suggests that mutations in this gene are associated with a variety of neuropsychiatric disorders consistent with its postsynaptic function. We find that TANC2 is expressed broadly in the human developing brain, especially in excitatory neurons and glial cells, but shows a more restricted pattern in Drosophila glial cells where its disruption affects behavioral outcomes.

We analysed the polysomal mRNA and total mRNA during Col-0 seed maturation The aim was to investigate the translational dynamics during seed maturation

Seed maturation is an important plant developmental process that follows embryo development. It is associated with a series of physiological changes such as the establishment of desiccation tolerance, seed longevity and seed dormancy. However, the translational dynamics associated with seed maturation, especially its connection with seed germination remains largely elusive. Here transcriptome and translatome profiling were performed during seed maturation. During seed maturation we observed a gradual disappearance of polysomes and a relative increase of monosomes, indicating a gradual reduction of global translation. Comparing the levels of polysomal associated mRNAs with total mRNA levels showed that thousands of genes are translationally regulated at early sates of maturation, as judged by dramatic changes in polysomal occupancy. By including previous published data from germination and seedling establishment, a translational regulatory network: SeedTransNet was constructed. Network analysis identified hundreds of gene modules with distinct functions and transcript sequence features indicating the existence of separate translational regulatory circuits possibly acting through specific regulatory elements. The regulatory potential of one such element was confirmed in vivo. The network identified several seed maturation associated genes as central nodes, and we could confirm the importance of many of these hub genes with a maturation associated seed phenotype by mutant analysis. One of the identified regulators an AWPM19 family protein PM19-Like1 (PM19L1) was shown to regulate seed dormancy and longevity. This putative RBP also affects the transitional regulation of one its, by the SeedTransNet identified, target mRNAs. Our data shows the usefulness of SeedTransNet in identifying regulatory pathways during seed phase transitions

We analyzed the monsome and polysome associated transcripts of seeds and seedlings and identify transcripts specifically associated with monosome and polysome in both tissues. The aim was to generate a global view about the state of mRNA storage in the seeds and the their fate during seed germination

Study of liquid film dynamics promotes understanding the critical heat flux (CHF) of boiling heat transfer, which occurs as the liquid layers (micro-layer and macro-layer) near the heater wall lose their integrity. Since the measurement at micro-scale is a challenge, and further complicated by the chaotic nature of the boiling process, profound knowledge on the thin liquid film dynamics is not well documented in the existing literature. In the present paper, we employ a confocal optical sensor system to study the dynamics and the integrity of a thin liquid film sheared by the co-flowing air from above and heated from below in a horizontal aluminum channel. The results indicate that the entrainment governs the liquid film thinning process under adiabatic or lower heat flux conditions, whereas the evaporation becomes more pronounced in a higher heat flux system. The detailed evolution of liquid film is discussed. Based on our experimental observations, the critical film thickness of an integral film is related to the condition of the heating surface and the heat flux. For a specific surface, the critical film thickness remains constant under a defined heat flux and increases with the increasing heat flux. A spectrum analysis is also implemented to analyze the film instability. It is concluded that the heat flux is the dominant factor to govern the film instability compared with the effect of differential velocities of gas and liquid flow., QC 20170619

Seeds are unique structures in the plant life cycle. The variation in the timing of seed maturation, dispersion, and the establishment of seed dormancy and longevity, increases the chances of plant survival and enlarge the distance that plants could disperse in the natural habitat. Seeds contain large amounts of mRNAs and the role of these mRNAs in seed dormancy and germination has been investigated in this thesis regarding their translational dynamics using Arabidopsis thaliana seeds as a model system. This study is facilitated by the translatome profiling technique, in which ribosomes are fractionated based on their engagement in translation followed by the high throughput profiling of the mRNAs associated to these ribosomes.Chapter 1 gives an overview of physiological seed traits (dormancy, germination, longevity) related to regulation of gene expression underlining the importance of translational control as well as a comprehensive description of the mechanisms involved in the regulation of mRNA translation. In Chapter 2, the translational dynamics from a quiescent dry seed to a seedling are described. The levels of polysome-associated mRNAs (translatome) are compared with the levels of the mRNAs in the total mRNA pool (transcriptome) in consecutive stages during seed germination. Two stages with extensive changes in translational efficiency were identified and named the Hydration Shift and Germination Shift stages, based on the time windows at which they were identified and that correspond to seed hydration and germination sensu stricto, respectively. Chapter 3 investigates seed stored mRNAs and mRNA binding proteins for their association with ribosomes (monosome/polysome). We show that mRNAs co-purify with monosomes and approximately 30% of these monosome associated mRNAs are translationally up regulated upon seed imbibition while seed mRNAs that are associated to polysomes are mostly leftovers from translation during late seed maturation. Fully matured seeds c

Mining medical datasets is a challenging problem before data mining researchers as these datasets have several hidden challenges compared to conventional datasets.Starting from the collection of samples through field experiments and clinical trials to performing classification,there are numerous challenges at every stage in the mining process. The preprocessing phase in the mining process itself is a challenging issue when, we work on medical datasets. One of the prime challenges in mining medical datasets is handling missing values which is part of preprocessing phase. In this paper, we address the issue of handling missing values in medical dataset consisting of categorical attribute values. The main contribution of this research is to use the proposed imputation measure to estimate and fix the missing values. We discuss a case study to demonstrate the working of proposed measure., Comment: 7 pages,ACM Digital Library, ICEMIS September 2015

© 2002-2012 IEEE. In this paper, we investigate the performance of a wireless relay network with multiple transmission sessions, in which multiple groups of source nodes communicate with their respective destination nodes via a shared wireless relay network. A multiple transmission session model with network code division multiplexing (NCDM) scheme is proposed to remove the inter-session interference at each destination. The fundamental idea of the NCDM scheme takes advantage of the property of G⊙ HT=0 of the low-density generator matrix (LDGM) codes. Based on the analysis of the NCDM scheme, we investigate the relationship among the equivalent received signal vector, the number of sessions and the column weight of the generator matrix. New code design criteria for the construction of the generator matrix is proposed. We further evaluate the multiple transmission session model with the proposed NCDM scheme in terms of throughput and complexity. Our evaluation demonstrates that the proposed scheme not only has a linear computational complexity, but also shows a similar error performance in the AWGN case and a considerable throughput improvement compared with its counterpart, which is referred to as a serial session scheme, where groups of source nodes communicate with their respective destinations in a time division manner.

© 2002-2012 IEEE. In this paper, we investigate the performance of a wireless relay network with multiple transmission sessions, in which multiple groups of source nodes communicate with their respective destination nodes via a shared wireless relay network. A multiple transmission session model with network code division multiplexing (NCDM) scheme is proposed to remove the inter-session interference at each destination. The fundamental idea of the NCDM scheme takes advantage of the property of G⊙ HT=0 of the low-density generator matrix (LDGM) codes. Based on the analysis of the NCDM scheme, we investigate the relationship among the equivalent received signal vector, the number of sessions and the column weight of the generator matrix. New code design criteria for the construction of the generator matrix is proposed. We further evaluate the multiple transmission session model with the proposed NCDM scheme in terms of throughput and complexity. Our evaluation demonstrates that the proposed scheme not only has a linear computational complexity, but also shows a similar error performance in the AWGN case and a considerable throughput improvement compared with its counterpart, which is referred to as a serial session scheme, where groups of source nodes communicate with their respective destinations in a time division manner.

The hotel industry is a mature industry marked by intense competition. Market share increases typically comes at a competitor’s expense. Industry-wide, most growth occurs in the international, rather than the domestic area. Hotels are a major employment generator in Hospitality industry. Work in the area of Hotel Management involves ensuring that all operations, including accommodation, food and drink and other hotel services run smoothly. It includes instructions in hospitality administration, hotel/motel management, restaurant and food services management, facilities planning, leisure studies, recreation administration, marketing, recreation equipment and grounds operations and maintenance, business finance, insurance and taxation, event management and guest services, personnel management, travel and logistics management, safety and health services, professional standards and ethics, and applications to specific vacation types and locations.

The critical heat flux (CHF) for boiling crisis is one of the most important parameters in thermal management and safe operation of many engineering systems. Traditionally, the liquid film flow model for "dryout" mechanism shows a good prediction in heated annular two-phase flow. However, a general assumption that the initial entrained fraction at the onset of annular flow shows a lack of reasonable physical interpretation. Since the droplets have great momentum and the length of churn flow is short, the droplets in churn flow show an inevitable effect on the downstream annular flow. To address this, we considered the effect of churn flow and developed the original liquid film flow model in vertical upward flow by suggesting that calculation starts from the onset of churn flow rather than annular flow. The results indicated satisfactory predictions with the experimental data and the developed model provided a better understanding about the effect of flow pattern on the CHF prediction., QC 20140312

Membrane, as a key component in all-vanadium redox flow batteries, plays the role of conducting the current and isolating the solutions between the anode and cathode electrodes. Both functional groups and charge numbers of membranes influence the performance of the battery. However, in simulating the species crossover through the membrane conventional models take account of mass transfer with the effect of functional groups in the membrane on crossover neglected. In this work, we propose an 1-D model for the membrane region of all-vanadium redox flow battery with the effect of functional groups considered. The model is formulated based on the conservation equations for charge and mass. Donnan potentials at the interfacial regions between membrane and electrodes are modeled, where the conditions are non-electrically neutral. The effects of various factors, including the state of charge, the number of functional groups and the applied current on species crossover are studied. It is shown that there exists a significant jump in electric potential and ion concentrations at the interfacial regions between membrane and electrodes. For a cation membrane, the concentrations of cations at the membrane side in the interfacial region are higher than those at the electrode side, while those of anions opposite. With more charges in the cation exchange membrane, the fluxes of vanadium ions crossover through the membrane are larger, leading to a lower efficiency. The model not only helps shed light into the mechanism of species crossover through the membrane, but also provides a tool to optimize the membrane design for all-vanadium flow batteries.

A profound knowledge of huge wave and droplet entrainment mechanism is crucial for the thorough study on the gas-liquid churn flow. Although studies have shown that the entrained fraction is high in churn flow and reaches the minimum around the churn-annular transition, the underlying mechanism of the drop entrainment in churn flow is still not well explored. To address this, we investigated the properties of the huge waves and the droplet entrainment in two vertical pipes with the inner diameter of 19. mm and 34. mm under churn flow conditions. We found that the flooding of the film was a characteristic of the churn flow throughout the regime. In addition, increasing the gas or liquid flow rate could lead to the transition from churn flow to annular flow or reverse to slug flow, providing the insight into the differences among slug, churn and annular flow. We also discussed the film instability under different flow conditions and tried to reveal the physical mechanism based on the instability analysis. In our study, the bag breakup and the ligament breakup were observed to coexist. The analysis of the liquid distribution in the cross-section of the pipes not only revealed the variations of the entrained fraction of churn flow from that of annular flow, but also indirectly illustrated the differences between their breakup mechanisms. Moreover, the wave properties (amplitude and frequency) were also analyzed in detail., Correction in: Chemical Engineering Science, vol. 158, page. 624. DOI:10.1016/j.ces.2016.10.042, ISI:000389068900061, ScopusID:2-s2.0-84994013663QC 20140108

Understanding the mechanism of droplet entrainment is of great importance for the churn flow. So far, the droplet entrainment mechanism has been experimentally studied; however, no detailed model is available for this particular flow pattern. To address this, the author established an analytical model to better understand the drop entrainment in churn flow. In this model, only the entrainment mechanism named shear-off in equilibrium state is considered and detailed analysis performed for the interface stability based on the Kelvin-Helmholtz instability and force balance acting on the wave crest. The model has been verified using experimental data and different parameters (e.g., pipe diameter, gas and liquid flowrate and pressure) influencing the entrainment is presented. The author proposed a more accurate and reasonable formula for the entrained rate in churn flow based on the existing formula for annular flow. The model developed in this paper predicts the entrainment mechanism under churn flow condition to an accuracy of 30% which is essential for the development of mechanistic models to predict the dryout condition in the future., QC 20140108

In this paper, the recently research results of assembly process's simulation of high-field permanent-magnetic flux source is presented. A 2D vector Jiles-Atherton magnetic hysteresis model is employed in magnetic field finite element analysis. Abnormal magnetization phenomena of permanent magnetic material during the assembly process are simulated and the distribution and account of abnormal magnetization points is obtained. It can be a significant guide for the manufacture of magic ring. © 2012 IEEE.

In this paper, the recently research results of assembly process's simulation of high-field permanent-magnetic flux source is presented. A 2D vector Jiles-Atherton magnetic hysteresis model is employed in magnetic field finite element analysis. Abnormal magnetization phenomena of permanent magnetic material during the assembly process are simulated and the distribution and account of abnormal magnetization points is obtained. It can be a significant guide for the manufacture of magic ring. © 2012 IEEE.

The application of the precoding technique to turbo codes is investigated, resulting in a new class of turbo-like codes named precoded turbo codes. The introduction of a precoder provides a degree of freedom for code optimisation. As a result, an optimised rate-1/2 precoded turbo code with a threshold of 0.28 dB is designed using the EXIT chart.

The application of the precoding technique to turbo codes is investigated, resulting in a new class of turbo-like codes named precoded turbo codes. The introduction of a precoder provides a degree of freedom for code optimisation. As a result, an optimised rate-1/2 precoded turbo code with a threshold of 0.28 dB is designed using the EXIT chart.

An approach to construct irregular repeat accumulate (RA) codes from circulant permutation matrices is presented. The constructed irregular RA codes can be encoded with shift registers and decoded in the turbo decoding fashion, which leads to a much faster convergence rate compared to the conventional full parallel decoding fashion.

An approach to construct irregular repeat accumulate (RA) codes from circulant permutation matrices is presented. The constructed irregular RA codes can be encoded with shift registers and decoded in the turbo decoding fashion, which leads to a much faster convergence rate compared to the conventional full parallel decoding fashion.

Document(en) uit de collectie Chemische Procestechnologie, DelftChemTech, Applied Sciences

Document(en) uit de collectie Chemische Procestechnologie, DelftChemTech, Applied Sciences

We present a concept for an Advanced Compton Telescope (ACT) based on the use of pixelized gas micro-well detectors to form a three-dimensional electron track imager. A micro-well detector consists of an array of individual micro-patterned proportional counters opposite a planar drift electrode. When combined with thin film transistor array readouts, large gas volumes may be imaged with very good spatial and energy resolution at reasonable cost. The third dimension is determined from the drift time of the ionization electrons. The primary advantage of this approach is the excellent tracking of the Compton recoil electron that is possible in a gas volume. Such good electron tracking allows us to reduce the point spread function of a single incident photon dramatically, greatly improving the imaging capability and sensitivity. The polarization sensitivity, which relies on events with large Compton scattering angles, is particularly enhanced. We describe a possible ACT implementation of this technique, in which the gas tracking volume is surrounded by a CsI calorimeter, and present our plans to build and test a small prototype over the next three years., Comment: 7 pages, 6 figures, to appear in New Astronomy Reviews (proceedings of the Seeon Conference "Astronomy with Radioactivities IV and Filling the Sensitivity Gap in MeV Astronomy")

We present a concept for an Advanced Compton Telescope (ACT) based on the use of pixelized gas micro-well detectors to form a three-dimensional electron track imager. A micro-well detector consists of an array of individual micro-patterned proportional counters opposite a planar drift electrode. When combined with thin film transistor array readouts, large gas volumes may be imaged with very good spatial and energy resolution at reasonable cost. The third dimension is determined from the drift time of the ionization electrons. The primary advantage of this approach is the excellent tracking of the Compton recoil electron that is possible in a gas volume. Such good electron tracking allows us to reduce the point spread function of a single incident photon dramatically, greatly improving the imaging capability and sensitivity. The polarization sensitivity, which relies on events with large Compton scattering angles, is particularly enhanced. We describe a possible ACT implementation of this technique, in which the gas tracking volume is surrounded by a CsI calorimeter, and present our plans to build and test a small prototype over the next three years., Comment: 7 pages, 6 figures, to appear in New Astronomy Reviews (proceedings of the Seeon Conference "Astronomy with Radioactivities IV and Filling the Sensitivity Gap in MeV Astronomy")