This paper presents a low-cost two-stage approximate multiplier for bfloat16 (brain floating-point) data processing. For cost-efficient approximate multiplication, the first stage implements ...Mitchell's algorithm that performs the approximate multiplication using only two adders. The second stage adopts the exact multiplication to compensate for the error from the first stage by multiplying error terms and adding its truncated result to the final output. In our design, the low-cost multiplications in both stages can reduce hardware costs significantly and provide low relative errors by compensating for the error from the first stage. We apply our approximate multiplier to the convolutional neural network (CNN) inferences, which shows small accuracy drops with well-known pre-trained models for the ImageNet database. Therefore, our design allows low-cost CNN inference systems with high test accuracy.
This paper proposes an approximate string matching with k-mismatches when calculating the generalized edit distance. When the edit distance is generalized, more sophisticated string matching can be ...provided. However, the execution time increases because of the bundle of complex computations for calculating complicated edit distances. The computational costs for finding which steps or edit distances are over k-mismatches cannot be significant in the generalized edit distance metric. Therefore, we can reduce the execution time by determining steps over k-mismatches and then skipping them. The diagonal step calculations using the pruning register skips unnecessary distance calculations over k-mismatches. The overhead of control statements and reordered memory accesses can be amortized by skipping multiple steps. Even though the proposed skipping method requires additional overhead, the proposed scheme's practical embodiments show that the execution time of string matching is reduced significantly when k is small.
Owing to its sustainability and environmentally friendliness, bacterial cellulose (BC) has received attention as a zero-waste textile material. Since the color of original BC was mostly yellowish ...white, a dyeing process is necessary to suggest BC as a textile. Thus, this study aimed to suggest a natural dyeing method using coffee to produce an eco-friendly coffee-dyed bacterial cellulose (BC-COF) bio-leather and to propose a reusing method as a dye adsorbent. To determine the dyeing and mordanting conditions with the highest color strength value, parameters such as dyeing temperature, time, mordanting methods were evaluated. Fourier-transform infrared spectroscopy and X-ray diffraction analysis confirmed that BC-COF was successfully colorized with coffee without changing its chemical and crystalline structures. In addition, field-emission scanning electron microscopy and Brunauer-Emmett-Teller surface area analysis confirmed that coffee molecules were successfully incorporated into fiber structures of BC. The effects of pH, concentration, temperature, and time on the adsorption of methylene blue dye using BC-COF bio-leather were also evaluated using ultraviolet-visible spectroscopy and zeta potential measurement. The results showed that BC-COF was found to be most effective when pH 6 of methylene blue solution with a concentration of 50 mg/L was adsorbed for 30 minutes at 25°C. Moreover, BC-COF could be reused for multiple times and had better dye adsorption rate compared to the original BC. From the results, it was confirmed that BC-COF could be employed as a dye adsorbent.
Display omitted
•The processes for producing MCCAs from real organic wastes are explored.•The reverse β-oxidation pathway during chain elongation is summarised.•The mixed culture operation strategies ...depending on type of feedstock are discussed.•Roles of each strain in environmental process for chain elongation are summarised.
Medium-chain carboxylic acid (MCCA) production from organic wastes has attracted much attention because of their higher energy contents and diverse applications. Anaerobic reactor microbiomes are stable and resilient and have resulted in efficient performance during many years of operation for thousands of full-scale anaerobic digesters worldwide. The method underlying how the relevant microbial pathways contribute to elongate carbon chains in reactor microbiomes is important. In particular, the reverse β-oxidation pathway genes are critical to upgrading short-chain fermentation products to MCCAs via a chain elongation (CE) process. Diverse genomics and metagenomics studies have been conducted in various fields, ranging from intracellular metabolic pathways to metabolic cascades between different strains. This review covers taxonomic approach to culture processes depending on types of organic wastes and the deeper understanding of genome and metagenome-scale CE pathway construction, and the co-culture and multi-omics technology that should be addressed in future research.
The first stretchable energy‐harvesting electronic‐skin device capable of differentiating and generating energy from various mechanical stimuli, such as normal pressure, lateral strain, bending, and ...vibration, is presented. A pressure sensitivity of 0.7 kPa‐1 is achieved in the pressure region <1 kPa with power generation of tens of μW cm‐2 from a gentle finger touch.
A colorimetric and ratiometric fluorescent probe consisting of a boron-dipyrromethene (BODIPY) dye conjugated with a 2-dicyanomethylene-3-cyano-2,5-dihydrofuran (DCDHF) group has been designed for ...the selective and sensitive detection of HOCl/OCl(-)via oxidative cleavage of an alkene linker between BODIPY and DCDHF.
A new design for fluorescence probes of esterase activity that features a carboxylate‐side pro‐fluorophore is demonstrated with boron dipyrromethene (BODIPY)‐based probes 1 a and 1 b. Because the ...design relies on the enzyme‐catalyzed hydrolysis of an ester group that is not electronically activated, these probes exhibit a stability to background hydrolysis that is far superior to classical alcohol‐side profluorophore‐based probes, large signal‐to‐noise ratios, reduced sensitivity to pH variations, and high enzymatic reactivity. The utility of probe 1 a was established with a real‐time fluorescence imaging experiment of endogenous esterase activity that does not require washing of the extracellular medium.
Stable but reactive: A new design for fluorescence probes of esterase activity that features a carboxylate‐side pro‐ fluorophore is demonstrated with boron dipyrromethene (BODIPY)‐based probes 1 a (R=Me) and 1 b (R=Bn). The utility of probe 1 a was established with a real‐time fluorescence imaging experiment of endogenous esterase activity that does not require washing of the extracellular medium.
Due to the prevalence of complex data, data heterogeneity is often observed in contemporary scientific studies and various applications. Motivated by studies on cancer cell lines, we consider the ...analysis of heterogeneous subpopulations with binary responses and high-dimensional covariates. In many practical scenarios, it is common to use a single regression model for the entire data set. To do this effectively, it is critical to quantify the heterogeneity of the effect of covariates across subpopulations through appropriate statistical inference. However, the high dimensionality and discrete nature of the data can lead to challenges in inference. Therefore, we propose a novel statistical inference method for a high-dimensional logistic regression model that accounts for heterogeneous subpopulations. Our primary goal is to investigate heterogeneity across subpopulations by testing the equivalence of the effect of a covariate and the significance of the overall effects of a covariate. To achieve overall sparsity of the coefficients and their fusions across subpopulations, we employ a fused group Lasso penalization method. In addition, we develop a statistical inference method that incorporates bias correction of the proposed penalized method. To address computational issues due to the nonlinear log-likelihood and the fused Lasso penalty, we propose a computationally efficient and fast algorithm by adapting the ideas of the proximal gradient method and the alternating direction method of multipliers (ADMM) to our settings. Furthermore, we develop non-asymptotic analyses for the proposed fused group Lasso and prove that the debiased test statistics admit chi-squared approximations even in the presence of high-dimensional variables. In simulations, the proposed test outperforms existing methods. The practical effectiveness of the proposed method is demonstrated by analyzing data from the Cancer Cell Line Encyclopedia (CCLE).
Nitrogen leaching from agricultural soils is a major source of pollution for adjacent water systems. Biochar application to agricultural soils was reported to manageably reduce N leaching. For the ...sustainable use of biochar application, a mechanistic understanding of the changes in N leaching induced by biochar treatment is urgently needed. In this study, the effects of biochar rice (Oryza sativa L.) chaff application to rice paddy soil (sandy loam) on leaching and soil structure were investigated. Free‐draining lysimeters (0.2 m in diameter by 0.1 m in height) filled with 500 g of air‐dried soil were treated with biochar at 0, 2, and 10% application rates (BC0, BC2, and BC10, respectively) and N fertilizer (NH4Cl) at 0 and 100 kg ha−1 application rates (Fert0 and Fert100, respectively). During the 9‐wk incubation, the concentration of dissolved C in the leachates was higher in the soils treated with BC2 and BC10 compared with that treated with BC0 in the Fert0 soil while there were no significant differences among the biochar treatments in the Fert100 soil. This result indicated that the labile portion of the applied biochar C was utilized by microbes as the amended N was metabolized. Nitrate contents in leachates from the BC2 and BC10 treatments were significantly smaller than in those from the BC0 soil. Soil analysis showed that NH4+ content decreased and NO3– content increased under BC10 treatment compared with BC0 treatment in the Fert100 soil, indicating that net N mineralization in the soil was enhanced under biochar treatment. We suggested that the NO3– retention in the biochar‐treated soil was related to increased soil aggregation. The C contents in the wet stable aggregates of size 53 to 1000 μm were significantly increased by biochar addition. This size fraction of aggregates is related to soil mesopores, which are involved in the soil's water holding. The water holding capacity (WHC) was higher in the BC2 and BC10 soils than in the BC0 soil, suggesting that application of rice chaff biochar to rice paddy soil could reduce N leaching through the redistribution of soil pores by forming more wet stable aggregates.
PDF
