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In this paper we derive the Fisher information matrix (FIM) and Cramér-Rao lower bound (CRLB) for positioning a terminal with a planar large intelligent surface (LIS), under Rician channel. For a disk-shaped continuous LIS and a terminal located on the central perpendicular line (CPL) of the LIS, we obtain expressions for the CRLBs in the form of a single integration. For the situation that the terminal is far from the LIS compared to the LIS radius and the situation with an asymptotically large LIS, closed-form approximations of the CRLBs are derived, based on which scalings and properties of the positioning precision with respect to different system parameters are obtained. For positioning a terminal with arbitrary location, we derive closed-form expressions of the CRLBs when the terminal is far from the LIS and the wavelength is small. When the surface area is small and the path-loss exponent is not larger than 5, the CRLBs of a CPL-terminal are smaller than those of a non-CPL terminal for all three dimensions, while the reverse may occur when the surface area grows large enough. We also carry out a comparative study of the continuous and discrete models of the LIS. Numerical results are presented to validate the precision of our theoretical analysis and approximated performance.

PurposeTo report the 6-year incidence, causes and risk factors for vision loss (visual impairment (VI) and blindness), among elderly adults in rural southern China.MethodsPopulation-based, cohort study. Initiated in 2014, the study recruited participants aged 50 and older using random cluster sampling from Yangxi County. All eligible participants were invited to attend interviews and comprehensive eye examinations at the 6-year follow-up between November 2020 and March 2021. The WHO categories of vision loss were used to define incident cases of VI (3/60≤VA <6/12), moderate-to-severe VI (MSVI) (3/60≤VA<6/18) and blindness (VA <3/60) in the better-seeing eye.ResultsAmong the 5825 baseline participants, 3187 (64.4%) of 4946 surviving subjects participated in the 6-year follow-up. Based on presenting and best-corrected VA, respectively, the crude incidence rate of blindness was 0.8% (95% CI 0.5% to 1.1%) vs 0.3% (95% CI 0.1% to 0.5%), for MSVI 6.7% (95% CI 5.7% to 7.6%) vs 4.6% (95% CI 3.8% to 5.4%) and for any VI 16.1% (95% CI 14.5% to 17.6%) vs 12.9% (95% CI 11.6% to 14.1%). Cataract (48.3%) and refractive errors (44.4%) were the most common causes of vision loss. Factors significantly associated with greater incident vision loss were older age, female sex, less education, living alone and longer axial length (all p<0.05).ConclusionsSubstantial work is still required to reduce avoidable vision loss in rural China. Screening outreach and efforts to improve awareness which target the poorer and less educated are urgently needed to reduce the growing unmet need for eye care due to ageing.

A method for detecting protein molecules based on the tilted fiber Bragg grating (TFBG) surface plasma resonance (SPR) is proposed to achieve the quick online real-time detection of trace amount of proteins. The detection principles of the TFBG-SPR protein molecular probe are analyzed, and its feasibility is demonstrated. The intermediary material between the protein molecules and the golden layer outside of the fiber gratings is cysteamine hydrochloride. When the concentration of the cysteamine hydrochloride solution is 2 M, the shift of the TFBG resonance peak is 2.23 nm, illustrating that the cysteamine hydrochloride modifies the gold film successfully. IgG antigen solution is poured on the surface of the cysteamine hydrochloride modifying the gold-deposited TFBG. Finally, antigen-antibody hybridization experiment is carried out with a 10 mg/mL antibody solution, and after two hours of hybridization the resonance peak of the TFBG shifts 5.1 nm, which validates the feasibility and effectiveness of the TFBG-SPR protein molecular probe.

High-fructose syrup (HFS) is a sugar substitute widely used in food and beverages and can also be used as an inexpensive substrate for production of rare sugars, such as d-allulose (or d-psicose) etc. Biotransformation of HFS to produce d-allulose contained HFS, called High-allulose-fructose syrup (HAFS), can be used as a value added sweetener with healthy functions. The recombinant Escherichia coliexpressing glucose isomerase (GI) from Caldicellulosiruptor besciiDSM 6725 was constructed and used for production of HFS from d-glucose. A dual enzyme expression system for expressing above GI and d-allulose 3-epimerase (DAE or d-psicose 3-epimerase, DPE) from Ruminococcussp. 5_1_39BFAA was constructed for production of HAFS from d-glucose. The recombinant strains developed had strong substrate tolerance and high capacity in production of HFS and HAFS. The cultivation conditions of above strains were made, and the biotransformation conditions of HAFS catalyzed by the cells of two recombinant strains expressing GI and DAE, respectively, or by the cells of the single strain co-expressing GI and DAE were optimized. Under the optimum conditions, about 18.6, 110.4 and 163.8 g/L d-allulose can be obtained from 100, 600 and 900 g/L d-glucose respectively. The HAFS containing about 18.2% (163.8 g/L) d-allulose, 36.3% (326.7 g/L) d-fructose and 45.5% (409.5 g/L) d-glucose was obtained at the initial d-glucose concentration of 900 g/L catalyzed by the cells of the single strain co-expressing GI and DAE. The production process developed in this study was simple, highly efficient, and can provide reference for the production of HAFS.

This paper reports the application of the biomolecular probe sensor based on the tilted fiber Bragg grating (TFBG) surface plasma resonance (SPR) which can recognize the specificity of the specific molecule by depositing sensitive biological membrane outside the active golden layer. The method of self-assembly was used to make the fixed sensitive biological membrane to achieve the best effect in the experiment. To illustrate the specific recognition of the DNA molecule, the TFBG-SPR biosensor was exposed to complementary DNA solutions with the concentration of 0.1 mmol/L and 0.05 mmol/L, respectively. The resonance wavelength of the TFBG-SPR biosensor increased gradually, indicating that the hybridization with the complementary DNA molecules changed the effective refractive index in the vicinity of the golden layer. Furthermore, the results illustrated the feasibility of the biomolecular probe sensor based on the TFBG surface plasma resonance for detecting the specific molecule.

Abstract: Leptospirillum ferriphilum and Acidithiobacillus caldus are two important acidophilic microorganisms involved in iron and sulfur oxidation during bioleaching. Cell adsorption to mineral surfaces is important for the direct leaching or contact leaching of minerals. In this study, we report the competitive adsorption of binary mixtures of L. ferriphilum LF-104 and A. caldus MTH-04 onto pyrite surfaces. The Langmuir adsorption parameter (CAm) indicated that these two bacteria underwent competitive adsorption to pyrite. Real-time quantitive PCR was used to quantify the relative amounts of L. ferriphilum and A. caldus adsorbed onto the surfaces of pyrite following exposure to a mixture of these two organisms. The adsorption of L. ferriphilum was not affected by A. caldus. However, adsorption of A. caldus was greatly affected by the presence of L. ferriphilum. Zeta-potential measurements and FT-IR spectroscopic studies showed that L. ferriphilum had a higher electrostatic attraction towards pyrite when compared to A. caldus. Based on the above results, we propose a competitive adsorption model to explain the mechanism by which L. ferriphilum and A. caldus compete in their adsorption to pyrite, although L. ferriphilum dominated in the competitive adsorption process. This work provides a better understanding of the adsorption behavior of mixed microbial populations onto mineral surfaces.

Abstract: Two types of soliton deflexion of (1+3)D Kadomtsev–Petviashvili (K–P) equation are considered. Using the Hirota bilinear form and the new technique of “homoclinic test”, a type of exact periodic soliton solution of the K–P equation with positive transverse dispersion effects is obtained. Another type of periodic soliton solution is found by means of the periodic soliton solution of the K–P equation with negative transverse dispersion effects and a temporal and spatial transformation. It is also investigated that the equilibrium solution is an unique deflexion point, periodic soliton of traveling in different spatial directions will be interchanged with the solution varying from one side of to the other side. [Copyright &y& Elsevier]

A mathematical model was developed, based on the time dependent changes of the specific growth rate, for prediction of the typical microbial cell growth in batch cultures. This model could predict both the lag growth phase and the stationary growth phase of batch cultures, and it was tested with the batch growth ofTrichoderma reeseiandLactobacillus delbrucckii.

The time length required for the adaptation of AFP-27 hybridoma cells to high osmotic pressure and the effect of a gradual increase of osmotic pressure on monoclonal antibody production were investigated. When the cells were subjected to an increase of osmotic pressure from 300 mOsmol kg-1 to 366 mOsmol kg- 1, the intracellular content of osmoprotective free amino acids reached a maximum level 6 h after the osmotic pressure was increased to 366 mOsmol kg-1. The same time period of 6 h incubation at 366 mOsmol kg-1 was required to obtain a high growth rate of AFP-27 cells at 440 mOsmol kg-1 when the cells were subjected to a two-step increase of osmotic pressure from 300 mOsmol kg-1 to 366 mOsmol kg-1 and then to 440 mOsmol kg-1. The time length for the physiological adaptation of the cells to 366 mOsmol kg-1 was consequently estimated to be 6 h. Osmotic pressure during batch cultivation was gradually increased from 300 mOsmol kg-1 to 400 mOsmol kg-1 with an adaptation time of at least 6 h. The specific growth rates following a gradual increase of osmotic pressure were higher than those at a constant osmotic pressure of 400 mOsmol kg-1, while the specific monoclonal antibody production rate increased with the increase in the mean osmotic pressure. As a result, the cells grown under a gradual increase of osmotic pressure produced higher amounts of monoclonal antibodies than did those grown under constant osmotic pressure.

Based on the study respect to energy metabolism under high osmotic pressure and cell adaptation to the increase in osmotic pressure, a strategy of gradual increase in osmotic pressure was applied in monoclonal antibody (MAb) production. The specific production rate of MAb (qMAb) and MAb productivity at 388 mOsmol/kg were about 2 and 1.5 times higher, respectively, than those at the physiological osmotic pressure. The average specific rate of glucose consumption (vG) increased with osmotic pressure until 410 mOsmol/kg and then decreased. The specific consumption rate of glutamine (vGLN) increased slowly below 410 mOsmol/kg but rapidly above it. The yield of lactic acid from glucose (YL/G) increased above 410 mOsmol/kg and the yield of ammonia from glutamine increased monotonously with osmotic pressure which indicates a decreased energy yield from glucose and an increased energy yield from glutamine at osmolarity higher than 410 mOsmol/kg. Growth inhibition at 400 mOsmol/kg was greatly alleviated after incubated in 366 mOsmol/kg for 6 h. The intracellular osmoprotective amino acid contents were also reached highest at 6 h after incubation in 366 mOsmol/kg medium. With the strategy of gradual increase in osmotic pressure, MAb production was increased.

We present a novel n-type InGaAs quantum-well metal-oxide-semiconductor field-effect transistor (QW-MOSFET) fabricated by a self-aligned gate-last process and investigate relevant Si-like manufacturing issues in future III-V MOSFETs. The device structure features a composite InP/Al2O3gate barrier with a capacitance equivalent thickness (CET) of 3 nm and non alloyed Mo ohmic contacts. We have found that RIE introduces significant damage to the intrinsic device resulting in poor current drive and subthreshold swing. The effect is largely removed through a thermal annealing step. Thermally annealed QW-MOSFETs exhibit a subthreshold swing of 95 mV/dec, indicative of excellent interfacial characteristics. The peak mobility of the MOSFET is 2780 cm2V-1s-1.