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Power system network is one of the important targets of cyber attack.In order to ensure the safe operation of power system,network managers need to evaluate the network security risk.Usually,existing network security risk assessment framework only aims at a single scenario,and can not find the strategic attackers who use a variety of low-risk methods to achieve high-risk threat targets from large quantities of network security alerts.In order to meet the above challenges,this paper proposes a network security risk assessment method based on tactical correlation.In this method,the warning information generated on va-rious network security detection devices when an attacker implements a multi-step attack is associated to form an attack chain,and the security risk of the organization intranet is evaluated by calculating the threat,vulnerability,impact score of each node in the attack chain and the risk score of the whole attack chain.In order to verify the effectiveness and robustness of the proposed method,this paper selects a representative example to illustrate the specific implementation process of the proposed method for network security risk assessment in the organizational intranet.The example shows that the network security risk assessment framework based on the tactical association can correctly assess the harm of multi-step attack caused by low-risk alarm association to achieve high-risk targets,and is more robust than the traditional single scenario analysis method,which can better provide decision-making basis for organization decision-makers in network security risk management.

In order to overcome the difficulties that current attack graph model cannot reflect real-time network attack events,a method is proposed including a forward risk probability update algorithm and a forward-backward combined risk probability update algorithm,which meets the needs of real-time analyzing network security.It first performs specific quantitative analysis on the uncertainty of each node in the graph,and uses Bayesian networks to calculate their static probabilities.After that,it updates the dynamic probability of each node along the forward and backward paths according to the real-time network security events,instantly reflecting the changes of external conditions and assessing real-time risk levels across the network.Experimental results show that the method can calibrate and adjust the risk probability of each node according to the actual situation,which helps the network operator correctly understand the dangerous levels of the network and make better decision for defense and prevention of the next attack.

PURPOSE: To evaluate the micro-tensile bond strength of 3 different surface managements to non-carious sclerotic dentin. METHODS: Fifteen periodontal patients' occlusal wearing molars which were above 3rd degree were selected. The teeth were equally cut into two pieces along the buccolingual direction, and each piece was randomly divided into 3 groups. Group 1 was processed with polishing, group 2 was processed with EX-26 diamond bur and group 3 was processed with 5# round bur. All teeth were subjected to Optibond treatment, and then filled with composite resin (Premisa) and saved in normal artificial saliva (31X.) for 24 hours. At last, fatigue test pieces were made, the micro-tensile bond strength was evaluated and every specimen was examined under stero-microscope. The micro-tensile bond strength was analyzed with one-way analysis of variance using SPSS17.0 software package. RESULTS: The micro-tensile bond strength of the 3 groups were (10.48±1.29) MPa, (21.52±0.97) MPa and(16.30±1.02) MPa, respectively. The bond strength of EX-26 diamond bur group was significantly greater than that of the other 2 groups (P<0.05). The bond strength of 5* round bur group was significantly greater than that of polishing group (P<0.05). The breakage mostly happened in adhesive dentine surface. CONCLUSIONS: Non-carious sclerotic dentin which is processed with diamond bur has better microtensile bonding strength. [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the influence of Nd: YAG laser on micro-tensile bond strength of different adhesive systems to non-carious sclerotic dentin. METHODS: Fifteen human occlusal wearing molars which were above degree three were selected and cut into nearly equal halves, divided into A (A1, A2), B (B1, B2) and C (C1, C2) three groups at randomly Then the teeth were processed with Nd: YAG laser (1W, 10Hz), teeth in A2 and C1, were combined with Scotchbond(™), A1 and B1 were combined with Adper Prompt L-Pop, and B2 and C2 were combined with Clearfil SE Bond, filling with composite resin (Z350) and saving in normal saline (37°) for 24 hours. Then fatigue test pieces were made, the micro-tensile bond strength was evaluated and every specimen was examined under stern-microscope. The micro-tensile bond strength was performed using one-way analysis of variance using SPSS 13.0 software package. RESULTS: The micro-tensile bond strength of the three groups were Scotclibond(™) (22.96±4.93) MPa, Adper Prompt L-Pop (18.73±4.71) MPa, Clearfil SE Bond (19.81±5.36) MPa. The bond strength of Scotchbond™ compared with the other two bonding systems was statistically significant. The breakage mostly happened in adhesive dentine surface. CONCLUSION: Non-canons sclerotic dentin which is processed with Nd: YAG laser associated with Scotchbond ™ has better bonding strength. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the microtensile bond strength of pulse Nd:YAG laser to non-carious sclerotic dentin. METHODS: Ten extracted human teeth with dental attrition on occlusal surface were cut into nearly equal halves (about 12mm²),and randomly divided into two groups with 10 in each group. All teeth were bonded using an all-in-one self-etch dentin adhesive (Adper Prompt L-Pop) to composite resin after the teeth in the experimental group were processed with pulse Nd:YAG laser (1W, 10Hz). After 24 hours, under copious water spray the teeth were sectioned into 0.8mmx0.8mm columns with silicon carbide dish at low speed. The microtensile bond strengths of samples were measured. Each fractured specimen was examined under stero-microscope. Paired t test was used for analysis of the microtensile bond strengths between the two groups with SPSS13.0 software package. RESULTS: The microtensile bond strength in the experimental group and control group was (18.94±6.81)MPa and (15.76±5.61)MPa, respectively, the difference of these two groups was statistically significant (P<0.05). The fractured adhesive dentin surface was mainly adhesive failure mode. CONCLUSION: Pulse Nd:YAG laser(1W, 10Hz) can improve the strength of composite resin bonding to sclerotic dentin. [ABSTRACT FROM AUTHOR]

Background: The prognostic value of carbohydrate antigen 19-9 (CA19-9) is known to be affected by elevated bilirubin levels in patients with gallbladder carcinoma (GBC). The clinical significance of changes in the ratio of CA19-9 levels to total bilirubin (TB) levels in patients with GBC after curative-intent resection remains unknown. The aim of this study was to determine the prognostic value of changes in preoperative and postoperative CA19-9/TB ratio in these patients., Methods: Prospectively collected data on consecutive patients who underwent curative-intent resection for GBC between January 2015 and December 2020 stored in a multicenter database from 10 hospitals were analyzed in this retrospective cohort study. Based on the adjusted CA19-9 defined as the ratio of CA19-9 to TB, and using 2×10 3  U/µmol as the upper normal value, patients were divided into a normal group (with normal preoperative and postoperative adjusted CA19-9), a normalization group (with abnormal preoperative but normal postoperative adjusted CA19-9), and a non-normalization group (with abnormal postoperative adjusted CA19-9). The primary outcomes were overall survival (OS) and recurrence-free survival (RFS). The log-rank test was used to compare OS and RFS among the groups. The Cox regression model was used to determine factors independently associated with OS and RFS., Results: The normal group ( n =179 patients) and the normalization group ( n =73 patients) had better OS and RFS than the non-normalization group ( n =65 patients) (the 3-year OS rates 72.0%, 58.4% and 24.2%, respectively; the RFS rates 54.5%, 25.5% and 11.8%, respectively; both P <0.001). There were no significant differences between the normal and the normalization groups in OS and RFS (OS, P =0.255; RFS, P =0.130). Cox regression analysis confirmed that the non-normalization group was independently associated with worse OS and RFS. Subgroup analysis revealed that the non-normalization group of patients who received adjuvant therapy had significantly improved OS and RFS as compared to those who did not receive adjuvant therapy (OS, P =0.025; RFS, P =0.003)., Conclusions: Patients with GBC who underwent curative-intent surgical resection with postoperative abnormal levels of adjusted CA19-9 (the CA19-9/TB ratio) were associated with poorer long-term survival outcomes. Adjuvant therapy after surgery improved the long-term outcomes of these patients., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Molecular ferroelectric materials are widely applied in piezoelectric converters, non-volatile memorizers, and photovoltaic devices due to their advantages of adjustable structure, lightweight, easy processing, and environmental friendliness. However, designing multifunctional molecular ferroelectrics with excellent properties has always been a great challenge. Herein, a multiaxial molecular ferroelectric is successfully designed by modifying the quasi-spherical cation dabco with CuBr 2 to obtain halogenated [Bretdabco]CuBr 4 (Bretdabco = N -bromoethyl- N '-diazabicyclo [2.2.2]octane), which crystallizes in polar point groups ( C 6 ). Typical ferroelectric behaviors featured by the P-E hysteresis loop and switched ferroelectric domain are exhibited. Notably, the molecular ferroelectric shows a high T C of 460 K, which is rare in the field and could greatly expand the application range of this material. In addition, the band gap is adjustable through the regulation of halogen. Both the UV absorption spectra and theoretical calculations indicate that the molecular ferroelectrics belong to a direct band gap (2.14 eV) semiconductor. This tunable and narrow band gap semiconductor molecular ferroelectric material with high T C can be utilized more effectively in the study of optoelectronics and sensors, including piezoelectric energy harvesters. This research may provide a promising approach for the development of multiaxial molecular ferroelectrics with a tiny band gap and high T C .

Purpose: To evaluate the micro-tensile bond strength of 3 different surface managements to non-carious sclerotic dentin., Methods: Fifteen periodontal patients' occlusal wearing molars which were above 3rd degree were selected. The teeth were equally cut into two pieces along the buccolingual direction, and each piece was randomly divided into 3 groups. Group 1 was processed with polishing, group 2 was processed with EX-26 diamond bur and group 3 was processed with 5# round bur. All teeth were subjected to Optibond treatment, and then filled with composite resin (Premisa) and saved in normal artificial saliva (37 degrees centigrade) for 24 hours. At last, fatigue test pieces were made, the micro-tensile bond strength was evaluated and every specimen was examined under stero-microscope. The micro-tensile bond strength was analyzed with one-way analysis of variance using SPSS17.0 software package., Results: The micro-tensile bond strength of the 3 groups were (10.48±1.29) MPa, (21.52±0.97) MPa and(16.30±1.02) MPa, respectively. The bond strength of EX-26 diamond bur group was significantly greater than that of the other 2 groups (P<0.05). The bond strength of 5# round bur group was significantly greater than that of polishing group (P<0.05). The breakage mostly happened in adhesive dentine surface., Conclusions: Non-carious sclerotic dentin which is processed with diamond bur has better micro-tensile bonding strength.

Objective: To investigate the effect of Nd:YAG laser on microtensile bond strength of single bond adhesive system for non-carious sclerotic dentin., Methods: Ten human molars with occlusal wearing were cut into equal halves (nearly 12 mm(2)), and randomly divided into experimental group and control group. The teeth in experimental group were processed with Nd:YAG laser (1 W, 10 Hz), and then applied with Scotchbond and filled with Z350 resin. In control group, the teeth were processed with single bond and filled with Z350 resin. The specimens were sectioned, and the microtensile bond strengths of each sample was tested by a universal testing machine., Results: The bond strength of the experimental group [(26.11 ± 1.62) MPa] was significantly higher than that of the control group [(22.27 ± 2.16) MPa], P < 0.05. Stero-microscope examination indicated that most of the fractures occurred in dentin-resin interface., Conclusions: Nd:YAG laser can increase the microtensile bond strength of single bond adhesive system in non-carious sclerotic dentin.

Objective: To quantify the interleukin (IL)-1beta mRNA and IL-6 mRNA expression induced by lipopolysaccharides ([PS) extracted from Porphyromonoas endodontalis (P. endodontalis) in osteoblasts, and to relate P. endodontalis LPS to the bone resorptive pathogenesis in the lesions of chronic apical periodontitis., Methods: MG63 cells was pretreated with PD98059 or SB203580 for 1 h and then treated with P. endodontolis LPS for 6 h. The expression of IL-1beta mRNA and IL-6 mRNA were detected by reverse transcription polymerase chain reaction (RT-PCR) technique., Results: The production of IL-1beta mRNA induced by P. endodontalis LPS decreased in osteoblasts pretreated with PD98059. Both of the production of IL-1beta mRNA and JL-6 mRNA induced by P. endodontalis LPS decreased in osteoblasts pretreated with SB203580., Conclusion: The synthesis of IL-1beta mRNA stimulated by Pendodontalis LPS in MG63 probably occur via extracellular signal-regulated kinase (ERK) 1/2 and p38 mitogen activated protein kinase (MAPK) signal transduction system. The synthesis of IL-6 mRNA stimulated by P.endodontalis LPS in MG63 probahly occur via p38MAPK signal transduction system.

Purpose: To investigate the influence of Nd:YAG laser on micro-tensile bond strength of different adhesive systems to non-carious sclerotic dentin., Methods: Fifteen human occlusal wearing molars which were above degree three were selected and cut into nearly equal halves,divided into A(A1,A2),B(B1,B2) and C(C1,C2) three groups at randomly. Then the teeth were processed with Nd:YAG laser(1W, 10Hz),teeth in A2 and C1 were combined with Scotchbond, A1 and B1 were combined with Adper Prompt L-Pop,and B2 and C2 were combined with Clearfil SE Bond, filling with composite resin(Z350) and saving in normal saline (37 degrees centigrade) for 24 hours.Then fatigue test pieces were made, the micro-tensile bond strength was evaluated and every specimen was examined under stero- microscope.The micro-tensile bond strength was performed using one-way analysis of variance using SPSS13.0 software package., Results: The micro-tensile bond strength of the three groups were Scotchbond (22.96 + or - 4.93)MPa, Adper Prompt L-Pop(18.73 + or - 4.71)MPa, Clearfil SE Bond(19.81 + or - 5.36)MPa. The bond strength of Scotchbond compared with the other two bonding systems was statistically significant.The breakage mostly happened in adhesive dentine surface., Conclusion: Non-carious sclerotic dentin which is processed with Nd:YAG laser associated with Scotchbond has better bonding strength.

Purpose: To evaluate the microtensile bond strength of pulse Nd:YAG laser to non-carious sclerotic dentin., Methods: Ten extracted human teeth with dental attrition on occlusal surface were cut into nearly equal halves(about 12 mm(2)),and randomly divided into two groups with 10 in each group.All teeth were bonded using an all-in-one self-etch dentin adhesive(Adper Prompt L-Pop) to composite resin after the teeth in the experimental group were processed with pulse Nd:YAG laser(1 W,10 Hz). After 24 hours,under copious water spray the teeth were sectioned into 0.8 mm x 0.8 mm columns with silicon carbide dish at low speed. The microtensile bond strengths of samples were measured.Each fractured specimen was examined under stero-microscope. Paired t test was used for analysis of the microtensile bond strengths between the two groups with SPSS13.0 software package., Results: The microtensile bond strength in the experimental group and control group was (18.94+/-6.81)MPa and (15.76+/-5.61)MPa, respectively, the difference of these two groups was statistically significant(P<0.05). The fractured adhesive dentin surface was mainly adhesive failure mode., Conclusion: Pulse Nd:YAG laser(1 W,10 Hz) can improve the strength of composite resin bonding to sclerotic dentin.