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This paper proposes a driver integrated circuit (IC) for a GaN-based synchronous buck converter to minimized the dead-time loss of GaN devices and improve converter efficiency. The proposed adaptive control achieves minimized dead-time for any loading condition. A driver IC is fabricated in a 0.18 lm BCD process to verify the concept. The measurement result achieves only 0.7 ns and 0.8 ns dead-time at the minimum and maximum load condition, respectively. The efficiency improves 2.1% at 2 A full load compared to the fixed dead-time control counterpart.

Mungbean (Vigna radiata (L.) R. Wilczek), an important legume crop in Asia, is primarily cultivated in the central-southern region of western Taiwan. In 2020, mungbean exhibiting typical phytoplasma-induced disease symptoms such as witches’ broom, phyllody, virescence, and proliferation was observed in Yunlin County, Taiwan. Moreover, the seed harvested from diseased plants displayed premature germination. Transmission electron microscopy examination of leaf veins prepared from symptomatic mungbean demonstrated that the occlusion of sieve tubes resulted from the accumulation of phytoplasma-like bodies in sieve elements along with filament-like structures in sieve pores. The association of phytoplasma in symptomatic mungbean was confirmed by PCR analyses of the 16S ribosomal RNA (rRNA) and immunodominant membrane protein genes. Further analyses of the 16S rRNA-based phylogenetic tree and the iPhyClassifier-based virtual restriction fragment length polymorphism study demonstrated that the phytoplasma-associated mungbean phyllody disease identified in this study belongs to the 16SrII-V subgroup. BLAST analysis and the phylogenetic analysis indicated that the SAP11-like protein identified in mungbean phyllody disease is identical to peanut witches’ broom phytoplasma SAP11, which explains the witches’ broom phenotype observed in symptomatic mungbean. The results described in this report confirm that the 16SrII-V phytoplasma, a widely distributed phytoplasma associated with peanut witches’ broom disease in Taiwan, has also infected mungbean. This is not only the first instance of mungbean phyllody disease found in Taiwan but also the first instance of mungbean phyllody disease caused by 16SrII-V subgroup phytoplasma.

Visual perceptual dysfunctions were common in children with developmental delays, and have severe adverse impacts on children’s daily activities. Recent studies have shown that technologies such as virtual reality and imaging can provide a motivating and engaging tool for remediating visual perceptual dysfunctions. This study was aimed to present the work we were conducting in experimenting with augmented reality (AR) for visual perceptual rehabilitation in children with developmental delay. Sixty participants (mean age = 7.96 ± 1.4) were equally divided into an experimental group trained with proposed KBTS (KBTS group) and a control group trained using traditional visual perceptual training (TVPT group). Each group completed an 8-week training program (two 30-minute sessions per week). Visual perceptual assessments (Test of Visual Perceptual Skill- 3rd Edition, Beery-Buktenica Developmental Test of Visual-Motor Integration- 6th Edition) and functional outcome measures (Vineland Adaptive Behavior Scale- Chinese Version, School Function Assessment- Chinese Version) were administered to investigate the effectiveness of the intervention. The KBTS group significantly outperformed the TVPT group in assessments of visual-motor integration, visual perceptual skills, and school functions. The effectiveness of the KBTS was supported by robust effect sizes for the pre- and post-intervention comparisons of visual perceptual and visual motor integrative functions between the KBTS group and the TVPT group. This study suggests that KBTS effectively improves visual-motor integration and overall visual perceptual functions in children with developmental delays. This study has discussed the ideas for incorporating several principles of game scenarios for visual perceptual rehabilitation, and the proposed KBTS still have raised a number of issues requiring further work. Enabling users to perform visual motor integrative tasks in an augmented reality world offers the potential for developing advanced visual perceptual skills which may be more easily transferable to activities of daily living than other techniques. Augmented reality has the potential to achieve entertaining and satisfying outcomes for visual perceptual rehabilitation, and making use of the potential applications of AR technologies should be considered more beneficial for the home-based rehabilitation during the current pandemic situations. Other clinical applications are discussed as well.

In this paper, we focus on near-optimal designs for variable-length error-correcting (VLEC) codes, while considering the performance in terms of both the average codeword length (ACL) and the symbol-error rate (SER). The criteria for narrowing the search space and enhancing the SER performance are investigated. An efficient code construction algorithm is then devised based on a random search process. Taking advantage of the significantly reduced search complexity, we are able to construct near-optimal VLEC codes for large source alphabets. Numerical results obtained for various free distance values and alphabet sizes show that constructed VLEC codes have both reduced ACL values and enhanced SER performances. Performance improvement is more notable for large source alphabets.

Flyback converter with USB power delivery is widely used for fast-charging mobile devices. However, conventional solutions have issues such as lower efficiency, higher cost, a large number of external components, and lower loop gain bandwidth. In this article, a high-efficiency zero-voltage switching (ZVS) flyback converter with primary- and secondary-side control ICs is proposed to solve the aforementioned issues with high integration level. The proposed control replaces optocoupler to achieve ZVS and secondary-side-regulation (SSR) by a pulse transformer. The ICs further integrate the USB power delivery (PD) controller and the constant voltage (CV)/constant current (CC) loop compensation to reduce external components. The proposed control and small-signal model are illustrated and verified by the experiment. The control ICs were fabricated in a 180-nm BCD process. The implemented 20-V/3-A/60-W USB PD flyback converter achieved 93.5% maximum efficiency using Si power switches. The feasibility of the proposed converter is verified by a thorough test of programmable power supply (PPS) with various CC/CV levels and load/line transients.

Myasthenia gravis (MG), an acquired autoimmune-related neuromuscular disorder that causes muscle weakness, presents with varying severity, including myasthenic crisis (MC). Although MC can cause significant morbidity and mortality, specialized neuro-intensive care can produce a good long-term prognosis. Considering the outcomes of MG during hospitalization, it is critical to conduct risk assessments to predict the need for intensive care. Evidence and valid tools for the screening of critical patients with MG are lacking. We used three machine learning-based decision tree algorithms, including a classification and regression tree, C4.5, and C5.0, for predicting intensive care unit (ICU) admission of patients with MG. We included 228 MG patients admitted between 2015 and 2018. Among them, 88.2% were anti-acetylcholine receptors antibody positive and 4.7% were anti-muscle-specific kinase antibody positive. Twenty clinical variables were used as predictive variables. The C5.0 decision tree outperformed the other two decision tree and logistic regression models. The decision rules constructed by the best C5.0 model showed that the Myasthenia Gravis Foundation of America clinical classification at admission, thymoma history, azathioprine treatment history, disease duration, sex, and onset age were significant risk factors for the development of decision rules for ICU admission prediction. The developed machine learning-based decision tree can be a supportive tool for alerting clinicians regarding patients with MG who require intensive care, thereby improving the quality of care.

Commercially available novel cultivars of poinsettia, obtained through interspecific hybridization, were subject to colchicine-based mutagenesis to recover their fertility, enabling subsequent breeding. Mutagenic treatment was conducted at different concentrations of colchicine with either lanolin or cotton serving as the matrix. The results indicated that 1 day was the optimal duration of colchicine treatment and that suitable colchicine concentration varied by cultivar. Moreover, one-time treatment gave higher rates of both polyploidy and morphological mutant production than two-times treatment. Specifically, the poinsettia cultivars Dulce Rosa (5 mg·g−1 colchicine with lanolin; 10 mg·mL−1 colchicine with cotton) and Princettia-Hot Pink (15 mg·g−1 colchicine with lanolin; 10 mg·mL−1 colchicine with cotton) yielded relatively high polyploidy production efficiency and morphological mutation rate. Consequently, a total of three polyploidy mutants of ‘Dulce Rosa’ and 19 polyploidy mutants of ‘Princettia-Hot Pink’ were obtained. Both cultivars had mutants with recovered fertility, with pollen germination rate of up to 27.5%. Moreover, unexpected non-polyploidy mutants with various morphological trait variations were also obtained.

Background Haworthia are desert succulents belonging to the Asphodelaceae family. Haworthia species are cultivated commercially as ornamentals and some rare species are quite valuable at retail market but growth slowly and difficult to propagation. However, an efficient micropropagation protocol was remained insufficient. Results The organogenic cultures obtained from inflorescence explants were cultured on Murashige and Skoog (MS) medium supplemented with various combinations of 6-benzylaminopurine (BA) and α-naphthalene acetic acid (NAA) under a light intensity of 10 μmol m−2 s−1 or 45 μmol m−2 s−1. The highest callus proliferation index (93.15%) with 1.0 mg L−1 BA + 0.1 mg L−1 NAA under a light intensity of 10 μmol m−2 s−1. The best shoot proliferation rates were on media with either 1 mg L−1 BA + 0–0.4 mg L−1 NAA (65.57–81.01%) under a light intensity of 45 μmol m−2 s−1. The highest root length (15.57 mm) and the highest rooting frequency (17 roots per shoot) were obtained when adventitious shoots were inoculated on MS medium with 0.4 mg L−1 NAA + 0.4 mg L−1 IBA. The survival rate of the transplanted plantlets was about 100%. The efficient micropropagation protocol proliferated Haworthia regenerate plants from inflorescence within 11 weeks. Conclusions The present study determined the best combination of light intensity and plant growth regulators (PGRs) for improved organogenesis of Haworthia during propagation by tissue culture. This optimized protocol showed light intensity is an important factor for efficient callus or shoot regeneration. These results indicate that it will be useful to optimize the light conditions for future commercial cultivation, germplasm conservation, genetic engineering and molecular biology research of this ornamental plant.

This paper presents a non-orthogonal multiplexing scheme using the concept of rateless coding for a downlink broadcast scheme with two users. The proposed approach does not require the inclusion of successive interference cancellation (SIC) techniques for signal detection when compared to the power-domain non-orthogonal multiple access (PD-NOMA) schemes. In various user pair scenarios, it is shown that the proposed scheme not only enhances the user transmission rate but also reduces the overhead required for reliable transmissions when compared to PD-NOMA-based schemes. To further enhance the error performance when considering both unconstrained and constrained inputs, a code design algorithm is proposed based on the transmission rate analysis. It is shown that the designed rateless multiplexing schemes achieve error performances that accurately approach the predicted performance limits.

Nutritional status is a predictor of mortality and morbidity in dialysis patients. This study aimed to assess dietary behaviors in dialysis patients compared to the recommendations of the Kidney Disease Outcomes Quality Initiative. Ninety five dialysis patients recruited from a hospital completed a 24-hour dietary recall questionnaire. Body weight, energy requirements, protein requirements, albumin, normalized protein catabolic rate, and 25(OH) vitamin D levels were measured. Of the 95 patients, 11 (11.6%) were below the desirable body mass index range, 59 (62.1%) were within the desired range, and 25 (26.3%) were above the desired range. However, only 32.7% of patients met the target energy intake, 29.5% reached the protein intake target, and 20.0% had adequate vitamin D concentrations. Vegetarian patients had lower energy, protein, fat, vitamin D intake, lower body mass index, serum blood urea nitrogen, creatinine, phosphate, normalized protein catabolic rate, and vitamin D status than the omnivorous patients (P

Generalized spatial modulation (GSM) is an attractive transmission technique for multiple-input multiple-output systems because of its spectral efficiency and energy efficiency. The maximum likelihood detector provides the optimal performance for GSM signal detection, but also leads to a high level of detection complexity. In this paper, both hard-decision and soft-decision detectors, which are based on a low-complexity codebook-assisted tree-search algorithm, are investigated. In addition, outer low-density parity-check codes are designed such that the concatenated schemes are able to provide error performances, which are very close to those of the schemes using conventional detectors, but with a much lower level of computational complexity.

In this paper, a cooperative single-carrier transmission scheme considering a distributed quasi-orthogonal space-frequency block code (QOSFBC) that provides improved peak-to-average power ratio (PAPR) performance is constructed for uplink communications. Focused on reducing the size and computational complexity, the source node, i.e., the mobile devices, is equipped with two transmit antennas, while only one antenna is required at the relay node in order to collaboratively generate a distributed QOSFBC signal using four transmit antennas. To achieve full diversity, a phase rotation strategy is proposed at the relay node. In addition, since single-carrier schemes considering SFBCs re-permute the spectral components of the transmitted signal and induce high PAPR value, a modified SFBC coding technique is proposed that allows the high-PAPR problem to be mitigated. Consequently, the designed distributed single-carrier frequency-division multiple access (SC-FDMA) QOSFBC scheme is able to provide full transmit diversity over frequency-selective fading channels, with a lower PAPR value on mobile devices when compared with a conventional SC-FDMA QOSFBC scheme.

Myasthenia gravis (MG) is an autoimmune disorder that causes muscle weakness. Although the management is well established, some patients are refractory and require prolonged hospitalization. Our study is aimed to identify the important factors that predict the duration of hospitalization in patients with MG by using machine learning methods. A total of 21 factors were chosen for machine learning analyses. We retrospectively reviewed the data of patients with MG who were admitted to hospital. Five machine learning methods, including stochastic gradient boosting (SGB), least absolute shrinkage and selection operator (Lasso), ridge regression (Ridge), eXtreme gradient boosting (XGboost), and gradient boosting with categorical features support (Catboost), were used to construct models for identify the important factors affecting the duration of hospital stay. A total of 232 data points of 204 hospitalized MG patients admitted were enrolled into the study. The MGFA classification, treatment of high-dose intravenous corticosteroid, age at admission, treatment with intravenous immunoglobulins, and thymoma were the top five significant variables affecting prolonged hospitalization. Our findings from machine learning will provide physicians with information to evaluate the potential risk of MG patients having prolonged hospital stay. The use of high-dose corticosteroids is associated with prolonged hospital stay and to be used cautiously in MG patients.

In this paper, we investigate Raptor-coded distributed unitary space–time modulation (USTM) schemes, where both the amplify-and-forward (AF) and decode-and-forward (DF) relaying scenarios are considered, under a wireless relay network with arbitrary path gains for the channel fading coefficients. First, the AF and DF relaying procedures are investigated based on the use of an inner USTM signal and an outer Raptor code, and the related noncoherent detectors are also derived. The constellation search for the USTM signal, as well as the optimization for the Raptor code, is then investigated in order to enhance the system performance. It is shown that the designed systems effectively approach the predicted limit in throughput performances and outperform the noncoherent distributed MIMO scheme reported in the previous literature.

Infections by microorganisms are a major problem in public health throughout the world. Artificial materials, including biomedical goods, inherently lack defense against microbial development. Therefore, microbial cells can adhere on any type of artificial surface, particularly in a moist environment, and start to multiply to form a huge population. In this review, we will discuss a strategy for designing antimicrobial polymers and antimicrobial surfaces. Generally, there are five types of antimicrobial polymers: (a) polymeric biocides, (b) biocidal polymers, (c) biocide-releasing polymers, (d) bioactive oligopeptides, and (e) antimicrobial surfaces. Antimicrobial surfaces preventing the growth of microorganisms are a promising method to inhibit the spread of microbial infections. The antimicrobial surfaces can reject the attachment of microbes and/or kill microbes in the vicinity and can be designed to kill microbes on contact. It is recommended that the material surface not release biocidal substances, therefore preventing exhaustion of biocide release to kill microbes. Furthermore, the antimicrobial surfaces are desired to be nontoxic to human cells. The development of contact-active antimicrobial surfaces by grafting antimicrobial nanosegments onto the material surface will be an important topic in the future.

Establishing cultures of human embryonic (ES) and induced pluripotent (iPS) stem cells in xeno-free conditions is essential for producing clinical-grade cells. Development of cell culture biomaterials for human ES and iPS cells is critical for this purpose. We designed several structures of oligopeptide-grafted poly (vinyl alcohol-co-itaconic acid) hydrogels with optimal elasticity, and prepared them in formations of single chain, single chain with joint segment, dual chain with joint segment, and branched-type chain. Oligopeptide sequences were selected from integrin- and glycosaminoglycan-binding domains of the extracellular matrix. The hydrogels grafted with vitronectin-derived oligopeptides having a joint segment or a dual chain, which has a storage modulus of 25 kPa, supported the long-term culture of human ES and iPS cells for over 10 passages. The dual chain and/or joint segment with cell adhesion molecules on the hydrogels facilitated the proliferation and pluripotency of human ES and iPS cells.

In this paper, we investigate differential amplitude/ phase modulation (APM) schemes for correlated Rayleigh fading channels. Considering the noncoherent maximum-likelihood receiver, a theoretical pairwise error probability (PEP) formula for differential signal vectors with arbitrary power values is derived. The design criterion for the signal set of differential vectors is then proposed based on the asymptotic analysis of the PEP. For both uncoded and coded APM schemes, the design criteria and optimization procedures for bit labeling rules are investigated. The designed differential APM schemes are shown to provide significant improvement in bit-error-rate performance, particularly in the error-floor regions.

In this paper, we investigate noncoherent transmission schemes using amplitude/phase modulation. For uncoded transmission schemes, we derive the pairwise error probability (PEP) and its high-SNR approximation for signal vectors with unequal power values using a noncoherent maximum-likelihood detector under Rayleigh block fading channels. For coded transmission schemes, we consider differential amplitude/phase modulated signals and introduce a codeword-interleaving strategy to improve the error performance. The design criteria for the signal labelling and bit interleaving are also derived via the high-SNR approximation of the PEP. At the receiver, we devise an iterative channel amplitude estimator to enhance the detection reliability. With the help of a specially-designed iterative receiving algorithm, the designed noncoherent coded scheme can provide a significant improvement, either in the error-floor or the waterfall region.

Alstom is developing concentrated solar power (CSP) utilizing 60/40wt% NaNO3-KNO3 molten salt as the working fluid in a tower receiver for the global renewable energy market. In the CSP power generation cycle, receivers undergo a daily cyclic operation due to the transient nature of solar energy. Development of robust and efficient start-up and shut-down procedures is critical to avoiding component failures due to mechanical fatigue resulting from thermal transients, thus maintaining the performance and availability of the CSP plant. The Molten Salt Central Receiver (MSCR) is subject to thermal transients during normal daily operation, a cycle that includes warmup, filling, operation, draining, and shutdown. This paper describes a study to leverage dynamic simulation and finite element analysis (FEA) in development of start-up, shutdown, and transient operation concepts for the MSCR. The results of the FEA also verify the robustness of the MSCR design to the thermal transients anticipated during the operation of the plant.

Foreign body-induced epiglottitis is rare and may not display typical manifestations of infectious epiglottitis. Besides, except for airway management and antibiotics treatment, the foreign body should be removed and accompanied complications, such as epiglottic abscess, also require adequate drainage. We reported on a patient admitted for epiglottitis and airway obstruction. Computed tomographic scan of the neck revealed an epiglottitis and a suspected retained epiglottic foreign body. The patient recovered completely after the removal of the foreign body and drainage of the abscess surgically. In the discussion, we describe the usefulness and limitations of laryngoscopic examination and computed tomographic scan of the neck for the evaluation of airway obstruction. If there is any suspicion of non-infectious causes of epiglottitis, or the response to treatment is inadequate, we suggest using varied diagnostic tools liberally to discover the accurate etiologies of epiglottitis.

As technology continues to shrink, reducing leakage is critical to achieving energy efficiency. Previous studies on low-power GPUs (Graphics Processing Units) focused on techniques for dynamic power reduction, such as DVFS (Dynamic Voltage and Frequency Scaling) and clock gating. In this paper, we explore the potential of adopting architecture-level power gating techniques for leakage reduction on GPUs. We propose three strategies for applying power gating on different modules in GPUs. The Predictive Shader Shutdown technique exploits workload variation across frames to eliminate leakage in shader clusters. Deferred Geometry Pipeline seeks to minimize leakage in fixed-function geometry units by utilizing an imbalance between geometry and fragment computation across batches. Finally, the simple time-out power gating method is applied to nonshader execution units to exploit a finer granularity of the idle time. Our results indicate that Predictive Shader Shutdown eliminates up to 60% of the leakage in shader clusters, Deferred Geometry Pipeline removes up to 57% of the leakage in the fixed-function geometry units, and the simple time-out power gating mechanism eliminates 83.3% of the leakage in nonshader execution units on average. All three schemes incur negligible performance degradation, less than 1%.

In this paper, we present a turbo coded space-time modulation scheme for noncoherent block fading channels, where neither the transmitter nor the receiver knows the channel state information. The turbo coded bits are divided into two parts which are respectively transmitted through information-bearing pilots and spatial multiplexing (SM). Since this approach effectively increases the cardinality of the set of possible transmit (space-time) signal matrices, a large rate gain can be obtained without increasing the modulation order, as shown through achievable-rate analysis. At the receiver, an iterative detection-decoding algorithm is performed cooperatively among the turbo decoder, the coherent demapper for the SM, and the noncoherent demapper for the information-bearing pilots through the help of the proposed signal matrix detector, which enables these two demappers to utilize the channel information inherent in all the received symbols within the same fading block. Compared to the previous work in the literature, the proposed scheme can provide advantages in both error performance and complexity.

Recrystallization and micronization for an antibacterial active pharmaceutical ingredient (API), sulfathiazole, was investigated in this study using the supercritical antisolvent (SAS) technology. The effects for the type of solvent, temperature and pressure on particle formation were investigated using the SEM, DSC and XRD analyses. It was observed that various solvents resulted in different polymorphisms. The original sulfathiazole had the crystal form III. It was recrystallized and micronized into form I when acetone was used as the solvent in the semicontinuous SAS process. The polymorph changed to form IV when ethanol was employed as the solvent. The mean particle size of sulfathiazole was reduced from its original 43.0 ± 15.5 μm to 2.1 ± 0.8 μm at the optimal operating condition. The optimally micronized sulfathiazole exhibited a much narrower particle size distribution. It also presented an enhanced dissolution rate by 3.2 times to the original API in a simulated intestinal fluid.

As the electromagnetic stirrers are commonly implemented in the continuous casting process of a steel mill, for enhancing the on-site controllability and productivity, it is convincible that detailed assessments about the three-dimensional characteristics of such equipments at different physical environments and material properties must be performed in the design stage. Since the stirrer system is mainly constructed based on the principles of linear induction machines, variations of the generated electromagnetic forces and magnetic fields will be highly affected by the system structures and input driving sources. Based on thorough three-dimensional steady-state and dynamic analyzing results, this paper will provide the summarized guidance for operations and designs of the in-mold electromagnetic stirrer for metal industry applications.

In this paper, we propose the use of a convolutional interleaver employing a variety of block delay parameters as the bit interleaver in a multiple-input-multiple-output (MIMO) bit-interleaved coded-modulation (BICM) scheme. The associated iterative decoding-detection algorithm is proposed, and the design criteria for the outer convolutional code are derived. The cases for both the perfect channel-state information (CSI) and the estimated CSI are investigated. In the proposed MIMO-BICM scheme, the MIMO detector and the channel estimator utilize the soft information passed from the sliding-window convolutional decoder within the same iteration, and hence, the convergence speed can be increased. Compared with the conventional scheme using various interleaver designs, the proposed scheme not only achieves better error performance for the first iteration but also has lower decoding latency. Consequently, the proposed scheme is suitable for delay-sensitive applications.

The solid solubilities of three active pharmaceutical ingredients (APIs) of antipyrine, 4-aminoantipyrine and 4-dimethylaminoantipyrine in supercritical carbon dioxide were measured by a semi-flow apparatus. The experiments were taken at 308.2, 318.2 and 328.2 K. The pressure range was from 10 to 22 MPa. These experimental results were correlated by the semi-empirical models of Mendez–Santiago–Teja and Chrastil. A solution model was also employed to fit the measured data. The average absolute relative deviation in solid solubility from semi-empirical models was 4–6%, and that from the solution model was 5–8%. The measured data satisfied the self-consistency test, and the parameters in the semi-empirical models are feasible for data extrapolation.

The Web has become an excellent source for gathering consumer opinions (more specifically, consumer reviews) about products. Consumer reviews are essential for retailers and product manufacturers to understand the general responses of customers to their products and improve their marketing campaigns or products accordingly. In addition, consumer reviews enable retailers to recognize the specific preferences of each customer, which facilitates effective marketing decisions. As the number of consumer reviews expands, it is essential and desirable to develop an efficient and effective sentiment analysis technique that is capable of extracting product features stated in consumer reviews (i.e., product feature extraction) and determining the sentiments (positive or negative semantic orientations) of consumers for these product features (i.e., opinion orientation identification). Product feature extraction is critical to sentiment analysis, because its effectiveness significantly affects the performance of opinion orientation identification, as well as the ultimate effectiveness of sentiment analysis. Therefore, this study concentrates on product feature extraction from consumer reviews. Specifically, we propose a semantic-based product feature extraction (SPE) technique that exploits a list of positive and negative adjectives defined in the General Inquirer to recognize opinion words semantically and subsequently extract product features expressed in consumer reviews. Using a prevalent product feature extraction technique and the SPE-GI technique (a variant of SPE) as performance benchmarks, our empirical evaluation shows that the proposed SPE technique outperforms both benchmark techniques.

The existing in-mold electromagnetic stirrers (M-EMS) that are widely applied in the steel industries have experienced low efficiencies due to the high operational temperatures and open system structures. Based on simple mechanical attachments and verified by detailed 3-D electromagnetic field analyses, this paper will propose a guided field path arrangement that can enhance the overall performance of an M-EMS system by a factor of 28% in the designated stirring directions while maintaining the same energy inputs. Such evident improvements will certainly provide a valuable design and adjustment guidance for the related metal industries.

The solid solubilities of cinnamic acid, phenoxyacetic acid and 4-methoxyphenylacetic acid in supercritical carbon dioxide were measured using a semi-flow apparatus. The experiments were taken at 308.2, 318.2 and 328.2 K. The pressure range was from 11 to 24 MPa. These data were confirmed as equilibrium solid solubilities based on a plug flow mass transfer model. The solid solubilities were further correlated using the equations of state or semi-empirical models. The correlation results are satisfactory with optimally fitted binary interaction parameters in the Peng–Robinson equation of state.

As technology continues to shrink, reducing leakage is critical to achieve energy efficiency. Previous works on low-power GPU (graphics processing unit) focus on techniques for dynamic power reduction, such as DVFS (Dynamic Voltage/Frequency Scaling) and clock gating. In this paper, we explore the potential of adopting architecture-level power gating techniques for leakage reduction on GPU. In particular, we focus on the most power-hungry components, shader processors. We observe that, due to different scene complexity, the required shader resources to satisfy the target frame rate actually vary across frames. Therefore, we propose the predictive shader shutdown technique to exploit workload variation across frames for leakage reduction on shader processors. The experimental results show that predictive shader shutdown achieves up to 46% leakage reduction on shader processors with negligible performance degradation.

A novel noncoherent block coding scheme, called noncoherent block-coded MPSK (NBC-MPSK), was proposed recently. In this paper, we present further research results on NBC-MPSK. We first focus on the rotational invariance (RI) of NBC-MPSK. Based on the RI property of NBC-MPSK with multistage decoding, a noncoherent near-optimal linear complexity multistage decoder for NBC-MPSK is proposed. Then we investigate a tree-search ML decoding algorithm for NBCMPSK. The derived algorithm is shown to have low complexity and excellent error performance. In this paper, we also utilize the idea of the NBC-MPSK to design noncoherent space-time block codes, called noncoherent space-time block-coded MPSK (NSTBC-MPSK). For two transmit antennas, we propose a signal set with set partitioning and derive the minimum noncohent distance of NSTBC-MPSK with this signal set. For the decoding of NSTBC-MPSK, we modify the ML decoding algorithm of NBC-MPSK and propose an iterative hard-decision decoding algorithm. Compared with training codes and unitary space-time modulation, NBC-MPSK and NSTBC-MPSK have larger minimum noncoherent distance and thus better error performance for the noncoherent ML decoder.

Transducin is a prototypic heterotrimeric G-protein mediating visual signaling in vertebrate photoreceptor cells. Despite its central role in phototransduction, little is known about the mechanisms that regulate its expression and maintain approximately stoichiometric levels of the α- and βγ-subunits. Here we demonstrate that the knock-out of transducin γ-subunit leads to a major downregulation of both α- and β-subunit proteins, despite nearly normal levels of the corresponding transcripts, and fairly rapid photoreceptor degeneration. Significant fractions of the remaining α- and β-subunits were mislocalized from the light-sensitive outer segment compartment of the rod. Yet, the tiny amount of the α-subunit present in the outer segments of knock-out rods was sufficient to support light signaling, although with a markedly reduced sensitivity. These data indicate that the γ-subunit controls the expression level of the entire transducin heterotrimer and that heterotrimer formation is essential for normal transducin localization. They further suggest that the production of transducin β-subunit without its constitutive γ-subunit partner sufficiently stresses the cellular biosynthetic and/or chaperone machinery to induce cell death.

The monolithic hysteresis-current-controlled (HCC) buck and boost converters with simplified convergence analysis methods are presented. The architectures of both converters are very simple and only consist of few components. The convergence condition, which is independent to duty cycle of converters, is derived in this paper. Using this concept to synthesize current-mode converters, the component values of converters will be designed easily. There is no sub-harmonic oscillation in the proposed converters without slope compensation even if the duty cycle greater than 50%. The proposed circuits are implemented into a single chip with TSMC 0.35 μm CMOS DPQM processes and their chip area is only 2.25 mm2, respectively. The maximum power efficiency of proposed converters is measured and described in this paper, too.

For over a decade, phosducin's interaction with the betagamma subunits of the G protein, transducin, has been thought to contribute to light adaptation by dynamically controlling the amount of transducin heterotrimer available for activation by photoexcited rhodopsin. In this study we directly tested this hypothesis by characterizing the dark- and light-adapted response properties of phosducin knockout (Pd- / -) rods. Pd- / - rods were notably less sensitive to light than wild-type (WT) rods. The gain of transduction, as measured by the amplification constant using the Lamb-Pugh model of activation, was 32% lower in Pd- / - rods than in WT rods. This reduced amplification correlated with a 36% reduction in the level of transducin betagamma-subunit expression, and thus available heterotrimer in Pd- / - rods. However, commonly studied forms of light adaptation were normal in the absence of phosducin. Thus, phosducin does not appear to contribute to adaptation mechanisms of the outer segment by dynamically controlling heterotrimer availability, but rather is necessary for maintaining normal transducin expression and therefore normal flash sensitivity in rods.

The tentative clinical application of human pluripotent stem cells (hPSCs), such as human embryonic stem cells and human induced pluripotent stem cells, is restricted by the possibility of xenogenic contamination resulting from the use of mouse embryonic fibroblasts (MEFs) as a feeder layer. Therefore, we investigated hPSC cultures on biomaterials with different elasticities that were grafted with different nanosegments. We prepared dishes coated with polyvinylalcohol-co-itaconic acid hydrogels grafted with an oligopeptide derived from vitronectin (KGGPQVTRGDVFTMP) with elasticities ranging from 10.3 to 30.4 kPa storage moduli by controlling the crosslinking time. The hPSCs cultured on the stiffest substrates (30.4 kPa) tended to differentiate after five days of culture, whereas the hPSCs cultured on the optimal elastic substrates (25 kPa) maintained their pluripotency for over 20 passages under xeno-free conditions. These results indicate that cell culture matrices with optimal elasticity can maintain the pluripotency of hPSCs in culture.

Several international legislations recently banned the use of Pb because of environmental concerns. The eutectic Sn-Ag solder is one of the promising candidates to replace the conventional Sn-Pb solder primarily because of its excellent mechanical properties. In this study, interfacial reaction of the eutectic Sn-Ag and Sn-Pb solders with Ni/Cu under-bump metallization (UBM) was investigated with a joint assembly of solder/Ni/Cu/Ti/Si3N4/Si multilayer structures. After reflows, only one (Ni,Cu)3Sn4 intermetallic compound (IMC) with faceted and particlelike grain feature was found between the solder and Ni. The thickness and grain size of the IMC increased with reflow times. Another (Cu,Ni)6Sn5 IMC with a rod-type grain formed on (Ni,Cu)3Sn4 in the interface between the Sn-Pb solder and the Ni/Cu UBM after more than three reflow times. The thickness of the (Ni,Cu)3Sn4 layer formed in the Sn-Pb system remained almost identical despite the numbers of reflow; however, the amounts of (Cu,Ni)6Sn5 IMC increased with reflow times. Correlations between the IMC morphologies, Cu diffusion behavior, and IMC transformation in these two solder systems will be investigated with respect to the microstructural evolution between the solders and the Ni/Cu UBM. The morphologies and grain-size distributions of the (Ni,Cu)3Sn4 IMC formed in the initial stage of reflow are crucial for the subsequent phase transformation of the other IMC.

Flip-chip interconnection technology plays a key role in today’s electronics packaging. Understanding the interfacial reactions between the solder and under-bump metallization (UBM) is, thus, essential. In this study, different thicknesses of electroplated Ni were used to evaluate the phase transformation between Ni/Cu under-bump metallurgy and eutectic Sn-Pb solder in the 63Sn-37Pb/Ni/Cu/Ti/Si3N4/Si multilayer structure for the flip-chip technology. Interfacial reaction products varied with reflow times. After the first reflow, layered (Ni1−x,Cux)3Sn4 was found between solder and Ni. However, there were two interfacial reaction products formed between solders and the UBM after three or more times reflow. The layered (Ni1−x,Cux)3Sn4 was next to the Ni/Cu UBM. The islandlike (Cu1−y,Niy)6Sn5 intermetallic compound (IMC) could be related to the Ni thickness and reflow times. In addition, the influence of Cu contents on phase transformation during reflow was also studied.