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In an attempt to understanding the complexity of the independent set problem, Chv{\'a}tal defined t-perfect graphs. While a full characterization of this class is still at large, progress has been achieved for claw-free graphs [Bruhn and Stein, Math.\ Program.\ 2012] and $P_{5}$-free graphs [Bruhn and Fuchs, SIAM J.\ Discrete Math.\ 2017]. We take one more step to characterize fork-free t-perfect graphs, and show that they are strongly t-perfect and three-colorable. We also present polynomial-time algorithms for recognizing and coloring these graphs.

Inspired by applications of perfect graphs in combinatorial optimization, Chv\'{a}tal defined t-perfect graphs in 1970s. The long efforts of characterizing t-perfect graphs started immediately, but embarrassingly, even a working conjecture on it is still missing after nearly 50 years. Unlike perfect graphs, t-perfect graphs are not closed under substitution or complementation. A full characterization of t-perfection with respect to substitution has been obtained by Benchetrit in his Ph.D. thesis. Through the present work we attempt to understand t-perfection with respect to complementation. In particular, we show that there are only five pairs of graphs such that both the graphs and their complements are minimally t-imperfect., Comment: Accepted to WG 2021

Rationale: Sporotrichosis is a subacute or chronic infection caused by sporothrix schenckii complex. The misdiagnosis rate of sporotrichosis is very high. Fungal microscopic examination and timely culture help us make an accurate diagnosis and treatment. We observed that combined treatments are more effective than monotherapy in treatment of sporotrichosis. Patient concerns: A 47-year-old female complained of pustules and scabs on her nose tip that lasted for 1 month at our hospital. She was diagnosed with skin infection and treated with antibiotics for 20 days. Nonetheless, the treatment did not result in any improvement with the lesion. Diagnoses: The results on bacterial culture, sensitive test, special stains, and multiple acid-fast cultures were negative. Finally, fungi were observed by KOH. Finally, fungal hyphae were observed by KOH and by fluorescent staining. Taupe filamentous colonies of sporothrix-like species appeared by fungal culture. The diagnosis of sporotrichosis was finally confirmed based on the lesion characteristics and the results of laboratory examination. Interventions: The lesions did not alleviate with Itraconazole oral administration for 1 month. Then we treated the patient with the combination therapy of itraconazole (ITR) and terbinafine. At the same time, the compound glycyrrhizin tablet was used for liver protection. Outcomes: The patient was free of clinical symptoms of sporotrichosis following the treatment and did not have complications during an 8-month follow-up. Lessons: We should always be alert to sporotrichosis although it is not a very common disease. It is important to adapt fungi microscopic analysis and culture for an accurate diagnosis. ITR is the first choice for sporotrichosis. However, combination treatment is more effective for stubborn cases.

The effective removal and recovery of phosphorus from aquatic environments are highly important for successful eutrophication control and phosphorus recycling. Herein, we prepared biochar containing MgO nanoparticles (MgO-biochar) by fast pyrolysis of MgCl2-impregnated corn stalks, probed its phosphate adsorption performance. Through the fast pyrolysis, the MgCl2 promoted the formation of micropores and mesoporous, and decomposed into MgO nanoparticles with the size smaller than 100 nm. The adsorption experiments showed that the adsorption property increased with the increase of Mg content, and had a strong correlation with the external surface area. And the phosphate adsorption was well described by the Langmuir-Freundlich model (maximum adsorption capacity was determined as 60.95 mg P/g). Kinetic analysis and characterization analysis of MgO-biochar for different adsorption time indicated that phosphate adsorption onto MgO-biochar was mainly controlled by rapid binding to the external surface (about 75% of the equilibrium adsorption amount), and the uptake rate was limited by the slow diffusion of phosphate into the biochar interior (about 25% of the equilibrium adsorption amount). The results suggested that the synthesized MgO-biochar with enough MgO active site dispersed on a higher external surface can be used as a potential adsorbent for phosphate removal and recovery from aqueous solution.

In this paper, we propose a novel technique to integrate the dual functions of radar and communication in a single platform, sharing the same frequency spectrum. The proposed technique utilizes the constellation mapping method to embed information symbols in the communication direction via transmit beamforming. By minimizing the integrated sidelobe level (ISL) for transmit beamforming, the system can achieve lower sidelobe level (SLL) for radar detection. The transmit level in the communication direction is controlled to ensure dependable communication transmission, taking into account the communication channel between the integrated platform and the communication station (i.e. communication distance and channel fading). We also investigate the communication performance in bit error rate (BER) with respect to angular error in transmit beamforming and resulting pointing error towards communication station. It is shown that our proposed method has better performance in BER and lower probability of interception (LPI) for communication transmission. Simulation results are presented to verify the theoretical derivations.

In the present study, the effects of aluminium (Al) concentrations on growth, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and phenylalanine ammonia-lyase (phenylalanine ammonia-lyase (PAL), EC 4.3.1.5) activities in Jatropha curcas L. seedlings were investigated. To carry out such investigations, J. curcas embryos were germinated and grown in vitro under Al concentrations of 0, 0.5, 1, 2 and 3 mM over a 7-day period. Biomass and the activities of antioxidant defense enzymes, such as SOD, POD, CAT and PAL in Jatropha curcas seedlings were observed. Results indicated that with the increasing Al concentrations, the biomass of cotyledons increased initially and then decreased but the biomass of hypocotyls and radicles decreased gradually. The SOD, POD, CAT and PAL activities in the cotyledons, hypocotyls and radicles were mainly increased, but the change trends were different. Key words: Aluminium (Al) toxicity, Jatropha curcas, antioxidative, plant defense system.

This paper discusses the spectrum of the energy-dependent neutron transport opertor in the anisotropic nonhomogeneous slab geometry with generalized boundary conditions. We prove the existence of a strictly dominant eigenavalue for this operator.

We prove a strong convergence theorem for an infinite family of asymptotically strict pseudo-contractions and an infinite family of equilibrium problems in a Hilbert space. Our proof is simple and different from those of others, and the main results extend and improve those of many others.

We introduce a new iterative scheme with a countable family of nonexpansive mappings for the variational inequality problems in Hilbert spaces and prove some strong convergence theorems for the proposed schemes.

The phonation frequencies of Jiao, Zhi and Yu of women with mild constitution are higher than the detection frequency of other phonations, In accordance with the theory of five Viscera harmonizing pitch, women is dominated by blood, the liver and kidney are 724 woman's congenital dependence and woman is apt to be influenced by feeling, etc. man are more prone to phonation of Yu and woman to phonation of Jiao, and the frequency of phonation is proportional to temperature, therefore, man has a hotter constitution than woman because the frequency of Yu phonation is higher than that of Jiao phonation.