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Analyst plays an important role in the development of an enterprise. Meanwhile, during the process of this development, it is important to gain financial support. Analysts' opinions can change public investors’ behavior and sentiments dramatically. However, the relationship between the three factors is still waiting to be discussed. This article focuses on the relationship between analysts’ attention, corporate finance, and corporate innovation, using OLS and Panel FE estimation methods to analyze the problem, and finally concludes that analysts’ attention can reduce financial constraints and then have a positive influence on corporate innovation. Moreover, compared with a large company, middle and small-sized enterprises are influenced more by this attention. Based on the research result, this article proposed that companies, especially the middle and/ or small-sized companies, should pay attention to making the third party (i.e., the analysts) interested in them and increase their exposure among the analysts and the public.

Volumetric solar evaporations by using light-absorbing nanoparticles suspended in liquids (nanofluids) as solar absorbers have been widely regarded as one of the promising solutions for clean water production because of its high efficiency and low capital cost compared to traditional solar distillation systems. Nevertheless, previous solar evaporation systems usually required highly concentrated solar irradiation and high capital cost, limiting the practical application on a large scale. Herein, for the first time in this work, polydopamine (PDA)-capped nano Fe3O4 (Fe3O4@PDA) nanofluids were used as solar absorbers in a volumetric system for solar evaporation. The introduction of organic PDA to nano Fe3O4 highly contributed to the high light-absorbing capacity of over 85% in wide ranges of 200–2400 nm because of the existence of numerous carbon bonds and pi (π) bonds in PDA. As a result, high evaporation efficiency of 69.93% under low irradiation of 1.0 kW m−2 was achieved. Compared to other nanofluids, Fe3O4@PDA nanofluids also provided an advantage in high unit evaporation rates. Moreover, Fe3O4@PDA nanofluids showed excellent reusability and recyclability owing to the preassembled nano Fe3O4, which significantly reduced the material consumptions. These results demonstrated that the Fe3O4@PDA nanofluids held great promising application in highly efficient solar evaporation.

To deal with water scarcity, solar steam generation has been widely regarded as one of the promising methods for freshwater production. In this work, for the first time, a novel recyclable MoS2-based nanocomposite (magnetic MoS2 nanosheets) was fabricated via the in-situ growth of nano Fe3O4 on the polydopamine (PDA)-functionalized MoS2 nanosheets, and subsequently applied as the solar absorber in the volumetric evaporation systems to generate solar steam. The magnetic MoS2 nanosheets showed a superhigh solar absorption of over 96% within the whole wavelength range of 200–2500 nm. As a result, a high evaporation efficiency of 79.2% under the low illumination of 2.5 kW m−2 was achieved. In addition, the magnetic MoS2 nanosheets not only showed the long-term well dispersion in aqueous solution due to the introduction of hydrophilic PDA, but also exhibited a fast and effective separation from aqueous solution with the help of the decorating nano Fe3O4, which much benefited to the continuously efficient solar steam generation and its good recyclability, respectively. Therefore, the MoS2-based nanomaterials in this work showed good prospects for solar energy harvesting.

Aerogels, with porous channels for water supply and vapor escape, can provide many inherent advantages in solar desalination and wastewater treatment. For the first time, this work demonstrates the preparation of a novel three-dimensional (3D) MoS2-based aerogel with high porosity and mechanical stability by a facile strategy for solar desalination. This 3D MoS2 aerogel has an excellent light-absorbing efficiency of over 95% within the whole solar spectrum range, enabling a high evaporation efficiency of 88.0% under a low solar irradiation of 1.0 kW m-2 and superhigh evaporation efficiencies of over 90% under a slightly enhanced solar irradiation of 1.5-3.0 kW m-2 as well as a remarkable desalination performance. In addition, the excellent mechanical stability of this MoS2 aerogel renders it to be reused for at least 10 cycles with stable water productivity. Because of its 3D architectures with high porosity and easy separation, this MoS2-based aerogel also provides promising applications in solar-driven water purification, sterilization, and so forth.

Molybdenum disulfide (MoS2) has emerged as a promising photothermal material for solar desalination. However, its limitation in integrating with organic substances constrains its application because of the lack of functional groups on its surface. Here, this work presents a functionalization approach to introduce three different functional groups (-COOH -OH -NH2) on the surface of MoS2 by combining them with S vacancies. Subsequently, the functionalized MoS2 was coated on the polyvinyl alcohol-modified polyurethane sponge to fabricate a MoS2-based double-layer evaporator through an organic bonding reaction. Photothermal desalination experiments show that the functionalized material has higher photothermal efficiency. The evaporation rate of the hydroxyl functionalized the MoS2 evaporator evaporation rate is 1.35 kg m−2 h−1, and the evaporation efficiency is 83% at one sun. This work provides a new strategy for efficient, green, and large-scale utilization of solar energy by MoS2-based evaporators.

Because of the easy-separation, high specific surface areas and rich binding sites, magnetic MoS2 with nanoscale architectures showed great potential in working as adsorbents for heavy metal ions. However, the general composites of nanoscale MoS2 and Fe3O4 suffered from the poor stability in acidic solution due to their entire exposures of Fe3O4 to H+, which made it difficult to regenerate the used adsorbents by the general acid treatment. This work reported a facile approach to prepare Fe3O4@Polydopamine (PDA)-MoS2 nanospheres via in-situ growth of MoS2 on the PDA modified Fe3O4 nanospheres. Fe3O4@PDA-MoS2 nanospheres possessed a fast adsorption of 2.4076 g/mg·min (Initial concentration of Pb2+: 200 mg/L) and high adsorption capacity of 508.9 mg/g at 298 K to Pb2+. This was because the specific surface area of MoS2 grown in-situ on Fe3O4@PDA was 7.6 times that of the pure MoS2, which significantly increased the binding sites of MoS2 for heavy metal ions. In addition, the as-prepared nanocomposites exhibited not only easy-separation within 120 s by an external magnet, but also long-term stability in strong acid solutions as well as facile regeneration by general acid treatment. The tight PDA layers outside the Fe3O4 nanospheres could work as not only a template for the formation of MoS2 nanoflowers but also an efficient protective coating for the improvement of the stability of nanocomposites. The findings might open up the possibility of expanding the practical application of nanoadsorbent in environmental remediation.

Epithelial-mesenchymal transition (EMT) plays an important role in peritoneal metastasis of Gastric cancer (GC). Tumor exosomes can mediate tumor directed metastasis, and TGF-β1 is an important factor in inducing tumor Epithelial mesenchymal transition. However, it is not clear whether GC derived exosomes can induce peritoneal mesothelial cells through the TGF-β1/ Smads pathway and the effect of injured peritoneal mesothelial cells on the biological characteristics of GC cells. In this study, we demonstrated that GC-derived exosomes can activate the TGF-β1/Smads pathway in peritoneal mesothelial cells and induce the corresponding EMT process, and that the injured peritoneal mesothelial cells can improve the migration and adhesion of GC cells. Taken together, these data further support the critical role of exosomes in the remodeling of the pre-metastatic microenvironment.

Molybdenum disulfide (MoS2) could be a promising electrode candidate for capacitive deionization (CDI) process benefited from the high specific area, excellent electronic conductivity, sound electrochemical stability, and good regenerability. In this work, a CDI study was performed on the desalination performance of water with defect-rich MoS2 sheets as the electrode, in which the defects were fabricated through thermal treatment. The MoS2 with abundant defects on the surface exhibited a much higher desalination capacity than that without any surface modification. The enhancement could be attributed to the abundant negative charges, high specific capacitance and low inner resistance of the defect-rich MoS2, which promoted the electrostatic attraction and electrosorption of Na+ to the electrode surfaces, as well as the formation of a thick electric double layer in the CDI process. The results suggested that defects can be incorporated on the surface of MoS2 for being a superb CDI electrode.

Nano-scale molybdenum disulphide sheets with large sulphur-rich surfaces could function as excellent scavengers for cadmium ions, based on the affinity of S to heavy metals. In this work, nano-scale molybdenum disulphide sheets were applied for cadmium uptake from aqueous solution. Transmission Electron Microscope (TEM) and Atomic Force Microscopy (AFM) studies demonstrated that as-prepared molybdenum disulphide nanosheets maintained the 2H-phase of the structure, with most of the sheets having less than five S–Mo–S layers. The adsorption results showed that nano-scale molybdenum disulphide sheets have an extremely high adsorption capacity (477 mg/g) for Cd2+, demonstrating that molybdenum disulphide nanosheets were excellent Cd2+ scavengers. Strong complexation between Cd2+ and the intrinsic S planes was proposed for the high adsorption of Cd2+ on molybdenum disulphide nanosheets, based on the results of XPS.

One feature of two-dimensional (2D) molybdenum disulfide nanosheets is the huge sulfur-rich surface area, which might lead to the strong adsorption of Hg2+ in water, because the sulfur on the surfaces could strongly bind to Hg2+. In this work, the adsorption of Hg2+ on 2D molybdenum disulfide sheets in water has been studied in order to develop a novel and efficient adsorbent for removing Hg2+ from water. The study was performed through the measurements of adsorption isotherm and kinetics, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS). The partially oxidized 2D molybdenum disulfide sheets with less than five S–Mo–S layers were prepared through the exfoliation of natural molybdenite. AFM observations illustrated a fast and multilayer Hg2+ adsorption on the surface of 2D molybdenum disulfide. The results of adsorption tests and SEM-EDS have indicated that 2D molybdenum disulfide was a superb adsorbent. The ads...

The preparation and characterization of nanoscale zero-valent iron-loaded porous sepiolite, as well as its application in the decolorization of methylene blue in aqueous solution, have been studied in this work through the measurements of field emission scanning electron microscope with energy dispersive spectrometry, x-ray photoelectron spectrometry, Fourier transform infrared spectroscopy and specific surface area. The results showed that nanoscale zero-valent iron particles were successfully loaded on the surface and interior pores of sepiolite through physical adsorption. It was revealed that the decoloration capacity of methylene blue on nanoscale zero-valent iron-loaded porous sepiolite in water was comparable to that of nanoscale zero-valent iron, and nine times higher than that of natural sepiolite. This indicates that porous sepiolite was a good supporter for the loading of nanoscale zero-valent iron and nanoscale zero-valent iron-loaded sepiolite was a good decolorant because of its high decoloration efficiency and easy separation.

Hydrophilic anti-fogging coatings have been applied in various aspects of life. In this work, a hydrophilic anti-fogging and frost-resisting coating which also exhibited self-healing property was prepared by 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and acrylic acid (AA). The coating possessed high transmittance in aggressive fogging conditions compared with bare glass, owing to its hydrophilic property. The behavior of water droplets on the poly(AMPS-co-AA) and polymer AMPS (PAMPS) coatings were observed, it could be found that the PAMPS coating tended to aggregate under the same fogging conditions. The fact was further confirmed by UV–vis-NIR analysis, the PAMPS coating enjoyed a lower UV–vis-NIR transmittance value than the poly(AMPS-co-AA) coating because of its aggregation after anti-fogging experiment. From the TG analysis, we also could conclude that the thermal stability of poly(AMPS-co-AA) coating was better than PAMPS coating. Contact Angle Analyzer, 1HNMR, ATR-FTIR, SEM, and AFM were also used to describe the composition, structure, and characterization of the coating.

The correlation of natural muscovite exfoliation with interlayer and solvation forces was investigated in this work, respectively. The former was studied through exfoliating seven muscovite samples with different interlayer forces in 40% tert-butanol/water solvent, while the latter was performed by exfoliating a muscovite in various alcohol/water solvents. This study was implemented by means of measurements using a UV-VIS spectrophotometer, surface tension measurements, XRD, IR spectroscopy, and ICP-OES. The results indicated that the exfoliation degree of natural muscovite was strongly related to the interlayer and solvation forces. Weak interlayer forces facilitated the exfoliation of muscovite, which might be due to the fact that the interlayer structure was easily broken down. Solvents with a larger molecular size and similar surface energy to the muscovite (around 54.8 mJ m−2) were better for the exfoliation. This observation was attributed to the fact that the molecules of the solvents had stronger solvation forces to muscovite layers, leading them to intercalate into the adjacent layers to overcome the interlayer interactions and thus the exfoliation.

Layered MoS2 and montmorillonite nanosheets were hybridized through a simple in-situ hydrothermal synthesis to develop an efficient catalyst (MoS2/MMT) for better exposure of the active sites on MoS2 toward Methyl Orange (MO) degradation, enable MoS2/MMT hybrid to achieve an excellent catalytic performance on MO removal. The characterizations of MoS2/MMT, based on XRD, FTIR, XPS, SEM, TEM, TGA, UV, contact angle detector and laser particle size analyzer, suggested that the montmorillonite nanosheets self-assemble into a cross-linked structure first, then the MoS2 nanosheets grew along the montmorillonite nanosheets surface, formed a cross-link atypical grid construction. The hybrid exhibited an excellent catalytic decomposition (98.6%) of MO into 4-amino-dimethylaniline and sulfanilic acid, much higher than that (48.6%) of pure MoS2, and the corresponding reaction rate of MoS2/MMT is about 8 times of MoS2. The superb decomposition capacity was found to be attributed to the more available of active sites and the high hydrophilicity of MoS2/MMT. The former greatly improved the hydrolysis of NaBH4 reductant, while the latter brought the catalyst a good dispersion in aqueous solutions. Furthermore, the hybrid performed a good catalytic reusability and stability. It is demonstrated that the MoS2/MMT hybrid might be an outstanding material in catalytic filed and water treatment.

Because of its special architectures and excellent capacitive property, molybdenum disulfide (MoS2) showed great potential in electrochemical-related applications. Nevertheless, the poor water wettability remains one of the primary weaknesses of MoS2 for its application in capacitive deionization (CDI). In this work, MoS2 was facilely modified by hydrophilic polydopamine (PDA) in a self-polymerization pathway to ameliorate the wettability of MoS2. With the soak time being carefully adjusted, MoS2 modified by PDA for 4 h (MoS2/PDA-4) could exhibit not only lower inner resistances due to its better wettability, but also much higher specific capacitance because of the incorporation of electroactive PDA compared to original MoS2, resulting in the enhanced electrosorption rate (less than 9 min) and desalination capacity (14.80 mg/g). Moreover, the electrochemical stability of MoS2/PDA-4 guaranteed the nanocomposites a good regenerability. The results suggested the MoS2/PDA-4 electrodes a promising material for CDI device.

In vehicle design modeling and simulation, surrogate model is commonly used to replace the high fidelity Finite Element (FE) model. A lot of simulation data from the high-fidelity FE model are utilized to construct an accurate surrogate model requires. However, computational time of FE model increases significantly with the growing complexities of vehicle engineering systems. In order to attain a surrogate model with satisfactory accuracy as well as acceptable computational time, this paper presents a model updated strategy based on multi-fidelity surrogate models. Based on a high-fidelity FE model and a low-fidelity FE model, an accurate multi-fidelity surrogate model is modeled. Firstly, the original full vehicle FE model is simplified to get a sub-model with acceptable accuracy, and it is able to capture the essential behaviors in the vehicle side impact simulations. Next, a primary response surface model (RSM) is built based on the simplified sub-model simulation data. Bayesian inference based bias term is modeled using the difference between the high-fidelity full vehicle FE model simulation data and the primary RSM running results. The bias is then incorporated to update the original RSM. This method can enhance the precision of surrogate model while saving computational time. A real-world side impact vehicle design case is utilized to demonstrate the validity of the proposed strategy.

Rear-end collision is one of the most common collision modes in China, which often leads to severe accident consequences. Autonomous Emergency Braking (AEB) system which can avoid or mitigate rear-end collision is one of the Advanced Driver Assistance System (ADAS) technologies. Traditional PID controller cannot effectively control the AEB system with strong nonlinear characteristics. Therefore, Back Propagation (BP) neural network PID controller is proposed in this paper. The PID parameters can be adjusted in real time based on the self-learning property and self-adapting property of BP neural network. The dynamics model is built in CarSim, and the inverse dynamics model is built in Simulink. Through the coordination control of the throttle angle and brake pressure, the host vehicle can brake automatically to avoid collisions in case of emergency. In addition, three kinds of test scenarios for the target car, stationary, slight braking, emergency braking, are setup based on complex environment in China. Finally, the simulations are conducted in these scenarios. And the simulation results indicate the feasibility and effectiveness of BP neural network PID controller in AEB system.

When solving real-world engineering problems, simplified models are commonly used to improve the calculation efficiency. However, the obtained simulation results are usually with low accuracy. Some researches are conducted to investigate the impact of feature-based model simplification on simulation results. First, models with similar features of different parameters are simplified. Then the simplified model and the corresponding original model are simulated in the same boundary conditions. And the simulation results between the simplified and original model are evaluated with some validation metrics. Finally, through an engineering case, some conclusions are obtained about the impacts of the features with different sizes and locations on simulation results.

Silver nanoparticles with hydrophobic surface (HS-nano-Ag) of small size ( 96%) against Staphylococcus aureus and Escherichia coli when containing a low content of HS-nano-Ag (100 ppm).

Molybdenum disulfide (MoS2)-based nanomaterials stand out from two-dimensional (2D) materials as a promising adsorbent for the removal of heavy metals from aqueous solution due to their extremely marvelous adsorption performances. The superb uptake capacity is primarily ascribed to the intrinsically rich S atoms exposed on the surface of MoS2, which distinguishes MoS2-based nanomaterials from other 2D materials. This work presents the latest advances of MoS2 nanomaterials as adsorbent for the removal of heavy metal ions in water. Various preparation methods, as well as the structure, property and modification of MoS2, is summarized. The adsorption capacity and mechanisms, affecting factors and regeneration are highlighted. The practical application of MoS2 as potential adsorbent for the removal of heavy metals from water is emphasized, and research needed for future application is simultaneously identified.

Our previous series of studies have proven that olfactory ensheathing cell (OEC) transplantation appears to be able to slow the rate of clinical progression after OEC transplantation in the first 4 months and cell intracranial (key points for neural network restoration, KPNNR) and/or intraspinal (impaired segments) implants provide benefit for patients (including both the bulbar onset and limb onset subtypes) with amyotrophic lateral sclerosis (ALS). Here we report the results of cell therapy in patients with ALS on the basis of long-term observation following multiple transplants. From March of 2003 to January of 2010, 507 ALS patients received our cellular treatment. Among them, 42 patients underwent further OEC therapy by the route of KPNNR for two or more times (two times in 35 patients, three times in 5 patients, four times in 1 patient, and five times in 1 patient). The time intervals are 13.1 (6–60) months between the first therapy and the second one, 15.2 (8–24) months between the second therapy and the third one, 16 (6–26) months between the third therapy and the fourth one, and 9 months between the fourth therapy and the fifth time. All of the patients exhibited partial neurological functional recovery after each cell-based administration. Firstly, the scores of the ALS Functional Rating Scale (ALS-FRS) and ALS Norris Scale increased by 2.6 + 2.4 (0–8) and 4.9 + 5.2 (0–20) after the first treatment, 1.1 + 1.3 (0–5) and 2.3 + 2.9 (0–13) after the second treatment, 1.1 + 1.5 (0–4), and 3.4 + 6.9 (0–19) after the third treatment, 0.0 + 0.0 (0–0), and 2.5 + 3.5 (0–5) after the fourth treatment, and 1 point after the fifth cellular therapy, which were evaluated by independent neurologists. Secondly, the majority of patients have achieved improvement in electromyogram (EMG) assessments after the first, second, third, and fourth cell transplantation. After the first treatment, among the 42 patients, 36 (85.7%) patients' EMG test results improved, the remaining 6 (14.3%) patients' EMG results showed no remarkable change. After the second treatment, of the 42 patients, 30 (71.4%) patients' EMG results improved, 11 (26.2%) patients showed no remarkable change, and 1 (2.4%) patient became worse. After the third treatment, out of the 7 patients, 4 (57.1%) patients improved, while the remaining 3 (42.9%) patients showed no change. Thirdly, the patients have partially recovered their breathing ability as demonstrated by pulmonary functional tests. After the first treatment, 20 (47.6%) patients' pulmonary function ameliorated. After the second treatment, 18 (42.9%) patients' pulmonary function improved. After the third treatment, 2 (28.6%) patients recovered some pulmonary function. After the fourth and fifth treatment, patients' pulmonary function did not reveal significant change. The results show that multiple doses of cellular therapy definitely serve as a positive role in the treatment of ALS. This repeated and periodic cell-based therapy is strongly recommended for the patients, for better controlling this progressive deterioration disorder.

To analyze the therapeutic effect of olfactory ensheathing cells (OECs) transplantation for central nervous system diseases.Between November 2001 and January 2008, 1,255 participants with central nervous system diseases were enrolled in this clinical study for fetal OECs transplantation. There were 928 males and 327 females aged 1.2-87 (mean 40) years. The course of disease was (4.52 +/- 4.67) years. Among them, 656 participants suffered from chronic spinal cord injury (SCI), 457 amyotrophic lateral sclerosis (ALS), 68 cerebral palsy (CP), 20 multiple sclerosis (MS), 11 the sequelae of stoke, 10 ataxia, and 33 residual diseases. The participants came from 71 countries or regions. Accidentally abortional fetal olfactory bulbs were donated voluntarily and were cultured for 2 weeks, then were transplanted.One thousand one hundred and twenty-eight cases were followed up for 2-8 weeks (mean 4 weeks) to obtain integrated data. Among them, the neurological functional amelioration was noticed in 994 participants with the overall short-term improvement rate of 88.12%. Seventy-six patients experienced the various perioperative complications with the incidence rate of 6.74%. One hundred and twenty patients with SCI received over 1 year follow-up. And according to ASIA assessment, motor scores increased from (39.82 +/- 20.25) to (44.55 +/- 18.99) points, light touch scores from (51.56 +/- 25.89) to (59.81 +/- 27.72) points, pain scores from (50.36 +/- 27.44) to (57.09 +/- 28.51) points for foreign patients (P0.05); motor scores increased from (40.52 +/- 20.80) to (46.45 +/- 20.35) points, light touch scores from (55.64 +/- 26.32) to (68.64 +/- 25.89) points, pain scores from (57.05 +/- 26.00) to (66.13 +/- 24.29) points for good rehabilitation Chinese patients (overall P0.05); motor scores from (37.03 +/- 18.52) to (38.03 +/- 18.50 points (P0.05), light touch scores from (45.88 +/- 22.56) to (46.63 +/- 23.09) points (P0.05), pain scores from (45.25 +/- 23.68) to (45.28 +/- 23.63) points (P0.05) for poor rehabilitation Chinese patients. Compared foreign patients and good rehabilitation Chinese patients with poor rehabilitation Chinese patients, difference in score change was remarkable (P0.05). One hundred and six cases of ALS, 32 CP, 8 MS, 7 ataxia, and 2 stroke sequelae were followed up for 3-48, 3-36, 2-20, 7-17, 6 and 24 months, One hundred and six cases of respectively. Majority of them (113/155, 72.9%) were benefited from OECs transplantation.OECs transplantation into brain and spinal cord is feasible and safe . The therapeutic strategy is valuable treatment for such central nervous system diseases such as chronic SCI, ALS, CP and stroke sequelae and can improve the patients' neurological functions and/or decrease the progressive deterioration.

To introduce a new functional self-assessment scale of amyotrophic lateral sclerosis (ALS).By comparing current different ALS functional scales and combining relative clinical experience and numeric pain intensity scale, ALS self-assessment scale was set down by International Association of Neural Restoration.ALS self-assessment scale included 3 categories with 18 items, adopting 10 points grading system, namely 10 was defined as the normal, 0 as the worst, and the total scores was 180. This scale included: (1) Bulbus medullae function: speech, swallowing, salivation, and tongue extension. (2) Limbs function: left arm movement, left hand movement, right arm movement, right hand movement, left leg movement, right leg movement, trunk movement, head-up, walking, and climbing stairs. (3) Others: breathing, muscular tone, pain, and muscle discomfort.ALS self-assessment scale is specifically designed for ASL patients. It can evaluate patient's function comprehensively and is simple and convenient, consuming less time.

Facial expression is an important communication method. Facial expression recognition has been studied in many application domains. In this paper, we study hidden Markov model (HMM) and K nearest neighbor (KNN) classifiers, and put forward a combined approach for facial expression recognition. The basic idea of this approach is to employ the HMM and KNN classifiers in a sequential way. First, the HMM classifier is used to calculate the probabilities of six expressions. From two most possible results of classification by HMM, the KNN classifier is used to make a final decision while the difference between the maximum probability and the second is less than the threshold obtained from HMM and training samples. The experiments show that the performance of this method exceeds that of solely HMM-based or KNN-based method.

The conventional method for parameter estimation of HMMs uses the Baum-Welch (BW) algorithm. However, the BW algorithm is highly sensitive to initial values of the model parameters. In this paper, we propose an Ant Colony Optimisation (ACO)-based BW algorithm (ACO-BW) for estimating the parameters of HMMs. Our approach benefits from the properties of ACO algorithms and the BW algorithm by combination of both into a single procedure. The improved ACO algorithm provides a new model of artificial ants which are characterised by a relatively simple but efficient strategy of prey search. This is performed by parallel local searches on hunting sites with sensitivity to successful sites. The ACO-BW algorithm also maintains the monotonic convergence property of the BW algorithm. Experimental results show that ACO-BW obtains better values for the likelihood function as well as higher recognition accuracy than that of the HMMs trained by other existing methods.