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Background Social media is a powerful tool for the dissemination of health messages. However, few studies have focused on the factors that improve the influence of health messages on social media. Objective To explore the influence of goal-framing effects, information organizing, and the use of pictures or videos in health-promoting messages, we conducted a case study of Sina Weibo, a popular social media platform in China. Methods Literature review and expert discussion were used to determine the health themes of childhood obesity, smoking, and cancer. Web crawler technology was employed to capture data on health-promoting messages. We used the number of retweets, comments, and likes to evaluate the influence of a message. Statistical analysis was then conducted after manual coding. Specifically, binary logistic regression was used for the data analyses. Results We crawled 20,799 Sina Weibo messages and selected 389 health-promoting messages for this study. Results indicated that the use of gain-framed messages could improve the influence of messages regarding childhood obesity (P Conclusions The findings suggested that gain-framed messages and statistical expressions can be successful strategies to improve the influence of messages. Moreover, appropriate pictures and videos should be added as much as possible when generating health-promoting messages.

Glaucocalyxin A (GLA) is a bioactive ent-kauranoid diterpenoid derived from the herbal medicine, Rabdosia japonica var. glaucocalyx, and it has been reported to possess marked anti-inflammatory properties. However, the underlying mechanisms are not fully understood. Here, we reported that GLA dramatically inhibited canonical and non-canonical NLRP3 inflammasome activation induced by multiple agonists. In addition, GLA also blocked NLRC4 inflammasome activation but had no effect on AIM2 inflammasome. Furthermore, we found that GLA inhibited NLRP3 or NLRC4 agonists-induced ASC oligomerization, which is an upstream event of the inflammasomes assembly. Most importantly, administration of GLA significantly reduced lipopolysaccharide (LPS)-induced mortality in septic-shock mouse model. Additionally, GLA dose-dependently inhibited the production of interleukin (IL)-1β, but had no effect on NLRP3-independent TNF-α production induced by LPS in vivo. In conclusion, our study suggests that GLA alleviates LPS-induced septic shock and inflammation via inhibiting NLRP3 inflammasome activation and provides a promising candidate drug for the treatment of NLRP3-driven diseases.

Uncontrolled activation of NLRP3 inflammasome initiates a series of human inflammatory diseases. Targeting NLRP3 inflammasome has attracted considerable attention in developing potential therapeutic interventions. Here, we reported that dehydrocostus lactone (DCL), a main component of Saussurea lappa from the traditional Chinese medicine, inhibited NLRP3 inflammasome-mediated caspase-1 activation and subsequent interleukin (IL)-1β production in primary mouse macrophages and human peripheral blood mononuclear cells and exerted an inhibitory effect on NLRP3-driven inflammation. Mechanistically, DCL significantly blocked the ASC oligomerization, which is essential for the assembly of activated inflammasome. Importantly, in vivo experiments showed that DCL reduced IL-1β secretion and peritoneal neutrophils recruitment in LPS-mediated inflammation mouse model, which is demonstrated to be NLRP3 dependent. These results suggest that DCL is a potent pharmacological inhibitor of NLRP3 inflammasome and may be developed as a therapeutic drug for treating NLRP3-associated diseases.

Objective: This study explored whether the efficacy of food safety education interventions can be increased by message framing among medical university students, and demonstrated the role of personal involvement within the message recipient in moderating framed effects. Methods: A cross-sectional study of food safety message framing was conducted among medical university students (randomly selected 1353 participants). An online self-administered questionnaire was used to collect information. Wilcoxon rank-sum test and Ordered multivariate logistic regression were utilised in the data analyses. Results: The present study showed significant differences in acceptance between the gain- and loss-framed groups (p &lt, 0.001). Participants with higher personal involvement had higher acceptance than those with low personal involvement in gain- and loss-framed message models (p &lt, 0.001). The acceptance of participants who were concerned about their health condition was higher than those who were neutral regarding their health condition (p &lt, 0.001) and participants who suffered a food safety incident had higher acceptance than those who did not (p &lt, 0.05). Conclusions: This study portrayed the selection preference of message framing on food safety education among medical university students in southwest China. Participants exposed to loss-framed messages had higher message acceptance than those exposed to gain-framed messages. Personal involvement may affect the food safety message framing. Public health advocates and professionals can use framed messages as a strategy to enhance intervention efficacy in the process of food safety education.

The issue of robust stability for fractional-order linear systems with polytopic uncertainties is dealt with in this paper. Based on the Kronecker product and μ-analysis, stable condition is established. Moreover, the robustness bounds of fractional-order linear systems with polytopic uncertainties are given. Two examples are presented to confirm the proposed conditions.

In this paper, we present a new criterion on robust stability of two-dimensional (2-D) linear discrete systems. This method is based on the discriminant systems of polynomial and Hurwitz theorem. By the fractional linear transformation, the problem of stability analysis for uncertain 2-D systems can be turned to a new problem whether the polynomials are Hurwitz stable, which can be easily checked by the discriminant system of polynomial. It simplifies some existing methods of analyzing stability for 2-D systems with uncertain parameters. A comparison is included to illustrate the presented criterion is more effective than previously reported criterion.

We aimed to analyze the outcomes of hypofractionated high-energy electron beam radiotherapy for the treatment of keloids. From February 1998 to January 2012, 568 patients with a total of 834 keloids underwent radiotherapy: 826 lesions with postoperative radiotherapy, and 36 with skin-grafting. Lesion size was >5 cm in 335 keloids. An electron-beam of 6 or 7 MeV was used, with a total dose of 18 Gy (two fractions with a 1-week interval) covering the lesion with a 1-cm margin. The time between surgery and radiotherapy was 24–48 h. Skin-grafted patients underwent radiotherapy 10–15 days after the operation. The median follow-up was 40 months (range: 12–160 months). The local control rate was 88.25% (736/834). The relapse rate was 9.59% (80/834), and the time to relapse was 6–28 months (median: 12 months). Univariate analyses showed that gender, age, keloid size, keloid site, skin grafting, and operation-to-irradiation interval influenced the local control rate. Multivariate analysis showed that the relapse rate was correlated with gender (P = 0.048), age (P < 0.01), operation-to-irradiation interval (P < 0.01), keloid site (P < 0.01), surgical method (P = 0.04) and keloid size (P < 0.02). Adverse effects were observed in 9.83% (82/834). No radiation-induced cancers were observed. Hypofractionated high-energy electron beam radiotherapy for keloids yielded excellent outcomes, especially in cases without skin grafting. Early postoperative radiotherapy with limited hypofractionation could be a good choice for keloid treatment.

The aim of this study was to develop a widely accepted prognostic nomogram for extranodal NK/T-cell lymphoma, nasal-type (NKTCL). The clinical data from 1383 patients with NKTCL treated at 10 participating institutions between 2000 and 2011 were reviewed. A nomogram was developed that predicted overall survival (OS) based on the Cox proportional hazards model. To contrast the utility of the nomogram against the widely used Ann Arbor staging system, the International Prognostic Index (IPI) and the Korean Prognostic Index (KPI), we used the concordance index (C-index) and a calibration curve to determine its predictive and discriminatory capacity. The 5-year OS rate was 60.3% for the entire group. The nomogram included five important variables based on a multivariate analysis of the primary cohort: stage; age; Eastern Cooperative Oncology Group performance status; lactate dehydrogenase; and primary tumor invasion. The calibration curve showed that the nomogram was able to predict 5-year OS accurately. The C-index of the nomogram for OS prediction was 0.72 for both cohorts, which was superior to the predictive power (range, 0.56-0.64) of the Ann Arbor stage, IPI and KPI in the primary and validation cohorts. The proposed nomogram provides an individualized risk estimate of OS in patients with NKTCL.

Oriented attachment (OA) growth has been a promising method for the synthesis of one dimensional (1D) anisotropic nanocrystals (NCs). An unresolved fundamental issue is to understand the growth mechanism at the initial stage of an OA nanorod (NR) growth. In this report, a collision–recrystallization model is proposed to investigate the initial OA growth of NRs. The repulsive electrical double layer (EDL) interaction and the attractive van der Waals (vdW) interaction at the initial OA stage are derived by the accurate surface element integration (SEI) technique and the classical Hamaker equation, respectively. Our results show that the self-recrystallization of nanochains increases the collision activation energy of NPs dramatically as their surface potentials and Hamaker constants increase. Under a specific electrolyte concentration, the collision activation energy reaches the maximum, indicating that the growth rate of OA can be controlled by adjusting the electrolyte concentration.

SSVEP is a kind of BCI technology with advantage of high information transfer rate. However, due to its nature, frequencies could be used as stimuli are scarce. To solve such problem, a stimuli encoding method which encodes SSVEP signal using Frequency Shift–Keying (FSK) method is developed. In this method, each stimulus is controlled by a FSK signal which contains three different frequencies that represent “Bit 0”, “Bit 1” and “Bit 2” respectively. Different to common BFSK in digital communication, “Bit 0” and “Bit 1” composited the unique identifier of stimuli in binary bit stream form, while “Bit 2” indicates the ending of a stimuli encoding. EEG signal is acquired on channel Oz, O1, O2, Pz, P3 and P4, using ADS1299 at the sample rate of 250 SPS. Before original EEG signal is quadrature demodulated, it is detrended and then band-pass filtered using FFT-based FIR filtering to remove interference. Valid peak of the processed signal is acquired by calculating its derivative and converted into bit stream using window method. Theoretically, this coding method could implement at least 2^(n-1) (n is the length of bit command) stimulus while keeping the ITR the same. This method is suitable to implement stimuli on a monitor and where the frequency and phase could be used to code stimuli is limited as well as implementing portable BCI devices which is not capable of performing complex calculations.

In the haze removal algorithm based on the atmospheric scattering model, atmospheric light value is an important parameter and its accuracy directly influences the quality of the haze removal results. Existing haze removal methods adopt a fixed number of atmospheric light candidate points for the clustering and statistic estimation of atmospheric light, with the maximum point cluster including candidate points. However, due to small candidate point samples, there is a high amount of error in the estimation of atmospheric light in a statistical sense. In order to solve that problem, this study uses the approach of dividing threshold values to select candidate points of atmospheric light and ant colony optimization to cluster point-clusters of atmospheric light. In this way, the number of candidate point samples and therefore the accuracy of estimate results of atmospheric light are increased. In addition, in order to improve the computational efficiency of the algorithm, this study first uses the K-means algorithm for a preliminary aggregation of atmospheric light candidate points, and then utilizes ant colony optimization to improve the clustering results. The experimental results prove that atmospheric light obtained using this method leads to more natural haze removal results, and further improves the index of image quality evaluation in the haze removal results.

Considering the problem of color distortion caused by the defogging algorithm based on dark channel prior, an improved algorithm was proposed to calculate the transmittance of all channels respectively. First, incident light frequency's effect on the transmittance of various color channels was analyzed according to the Beer-Lambert's Law, from which a proportion among various channel transmittances was derived; afterwards, images were preprocessed by down-sampling to refine transmittance, and then the original size was restored to enhance the operational efficiency of the algorithm; finally, the transmittance of all color channels was acquired in accordance with the proportion, and then the corresponding transmittance was used for image restoration in each channel. The experimental results show that compared with the existing algorithm, this improved image defogging algorithm could make image colors more natural, solve the problem of slightly higher color saturation caused by the existing algorithm, and shorten the operation time by four to nine times.

Purpose – In this study, the authors use the term “e-quality” to refer to information quality, system quality and service quality. This study aims to focus on e-quality, exploring and comparing users' perceptions of digital libraries and virtual communities in the hope that the results of this study can help lead to better understanding of the exact nature of e-quality as perceived by users. Design/methodology/approach – A large-scale survey was conducted for data collection. Data collected from 334 users of digital libraries and virtual communities were used for data analysis. Findings – The study finds that users are likely to perceive a higher level of information quality, system quality and service quality of digital libraries than of virtual communities. Practical implications – The authors suggest that librarians do not need to have concerns over the challenge brought by virtual communities, which indeed have an increasing impact on the way a lot of people seek and gather information. Instead, they should encourage their users to use both digital libraries and virtual communities. The authors believe that the usage of these two types of information sources by users can efficiently inform each other, thus facilitating the e-quality of both digital libraries and virtual communities to reach excellence. Originality/value – Building on the information systems (IS) success model, this study explores and compares users' perceptions of digital libraries and virtual communities in terms of e-quality, which the authors think presents a new view for digital library research and practice alike.

This paper considers controller parameterization method ofH∞control for polynomial Hamiltonian systems (PHSs), which involves internal stability and external disturbance attenuation. The aims of this paper are to design a controller with parameters to insure that the systems areH∞stable and propose an algorithm for solving parameters of the controller with symbolic computation. The proposed parameterization method avoids solving Hamilton-Jacobi-Isaacs equations, and thus the obtained controllers with parameters are relatively simple in form and easy in operation. Simulation with a numerical example shows that the controller is effective as it can optimizeH∞control by adjusting parameters. All these results are expected to be of use in the study ofH∞control for nonlinear systems with perturbations.

BACKGROUND Cucumber fruit is susceptible to chilling injury (CI), which could be accelerated significantly with subsequent shelf-life. This type of CI culminates in deterioration of organs and eventually leads to cell death. In this study, evidence of programmed cell death (PCD), involving cell death induced by cold stress, was investigated in cucumber. Harvested cucumber (Cucumis sativus L. cv. Zhexiu-1) fruits were stored at 2 °C for 3, 6 or 9 days and subsequently transferred to 20 °C for 2 days. RESULTS Significant cell death acceleration was observed upon reconditioning after 9 days' cold stress when the hallmark of PCD – DNA laddering – was clearly observed. Further evidence of nuclear DNA cleavage was confirmed by the in situ TdT-mediated dUTP nick end labeling (TUNEL) assay. Chromatin condensation and nucleus distortion were observed by nuclear staining of DPI. Ethylene burst was observed upon reconditioning after 9 days of consecutive cold stress. CONCLUSION The features of PCD process induced by reconditioning after cold stress in cucumber fruit may be mainly attributed to ethylene burst. © 2013 Society of Chemical Industry

Using the Hamiltonian function method, this paper proposes a family of robust adaptive excitation controllers for synchronous generators with steam valve control. First, a parameterization method of robust adaptive controllers is investigated for dissipative Hamiltonian systems. This method avoids solving Hamilton-Jacobi-Issacs inequalities. The parameters in the family of controllers thus obtained are determined by a locally positive semidefinite function, which has only 2n independent variables, twice as many as the one used to characterize the state feedback. Then, with the parameterization method and the structural properties of dissipative Hamiltonian systems, a family of robust adaptive excitation controllers is designed for synchronous generators with steam valve control, disturbances and unknown parameters. Simulations illustrate the effectiveness and feasibility of the excitation control strategy proposed in the paper.

Examples show that many integral forms can be efficiently verified to be positive through a special form of variable substitutions, i.e., weighted difference substitutions (WDS), but it was unknown how many steps of substitutions are needed, or furthermore, whether this method is adapted for checking positivity of all integral forms. In this paper, we give upper bounds of step numbers of WDS required in checking whether an integral form is positive or nonnegative, thus deducing that the positivity of integral forms can be completely verified through the WDS method.

SUMMARY Using structure properties of dissipative Hamiltonian systems, this paper investigates the parameterization problem of Hinfty controllers for such systems. A family of H∞ controllers with full information is first obtained by interconnecting an H∞ controller with a generalized zero-energy-gradient (ZEG) detectable, free generalized Hamiltonian system. Then, a family of H∞ controllers with partial information is presented in terms of the solution to an inequality only in 2n independent variables (twice as many as the one used to characterize the state feedback) and without imposing an additional cascade condition. Both of the parameterization methods avoid solving Hamilton–Jacobi–Issacs equations (or inequalities), and thus the proposed controllers are relatively simple in form and easy in operation. Numerical experiments show the effectiveness and feasibility of the proposed methods. Copyright © 2011 John Wiley & Sons, Ltd.

We present a new necessary and sufficient criterion to check the positive definiteness of Hermitian interval matrices. It is shown that an n × n Hermitian interval matrix is positive definite if and only if its 4 n - 1 ( n - 1 ) ! specially chosen Hermitian vertex matrices are positive definite.

We describe the synthesis of protected phosphoramidites of deoxyriboguanosine and guanosine derivatives containing a thiopropyl tether at the guanine N2 (7a,b) for site-specific crosslinking from the minor groove of either DNA or RNA to a thiol of a protein or another nucleic acid. The thiol is initially protected as a tert-butyl disulfide that is stable during oligonucleotide synthesis. While the completed oligonucleotide is still attached to the support, or after purification, the tert-butyl thiol can readily be removed or replaced by thioethylamine or 5-thio-2-nitrobenzoic acid, that have more favorable cross-linking rates.

K65R is a primary reverse transcriptase (RT) mutation selected in human immunodeficiency virus type 1-infected patients taking antiretroviral regimens containing tenofovir disoproxil fumarate or other nucleoside analog RT drugs. We determined the crystal structures of K65R mutant RT cross-linked to double-stranded DNA and in complexes with tenofovir diphosphate (TFV-DP) or dATP. The crystals permit substitution of TFV-DP with dATP at the dNTP-binding site. The guanidinium planes of the arginines K65R and Arg(72) were stacked to form a molecular platform that restricts the conformational adaptability of both of the residues, which explains the negative effects of the K65R mutation on nucleotide incorporation and on excision. Furthermore, the guanidinium planes of K65R and Arg(72) were stacked in two different rotameric conformations in TFV-DP- and dATP-bound structures that may help explain how K65R RT discriminates the drug from substrates. These K65R-mediated effects on RT structure and function help us to visualize the complex interaction with other key nucleotide RT drug resistance mutations, such as M184V, L74V, and thymidine analog resistance mutations.

A general parametric controller design method is proposed for Hopf bifurcation of nonlinear dynamic system. This method does not increase the dimension of the system. Compared with the existing methods, the controller designed by this method has a lower controller order and a simpler structure, and it does not contain equilibrium points. The method keeps equilibrium of the origin system unchanged. Symbolic computation is used to deduce the constraints of controller, and cylindrical algebraic decomposition is used to find the stability parameter regions in parameter space of controller. The method is then employed for Hopf bifurcation control. Taking Lorenz system as an example, the controller design steps of the method and numerical simulations are discussed. Computer simulation results are presented to confirm the analytical predictions.

We present a complete and practical algorithm which can determine the number of distinct real solutions of a given polynomial system of equations and inequalities with integer coefficients mechanically. Based on this algorithm, a program called nearsolve has been implemented in Maple. The algorithm and program have been successfully applied to many problems with various backgrounds and to automated discovering and proving for inequality-type theorems.

In this paper, we consider a polynomial differential system of degree n, which was given from a general multimolecular reaction in biochemistry as a theoretical problem of concentration kinetics. The high degree of polynomials involves so many difficulties that we hardly give coordinates of all equilibria, although that is basic for qualitative analysis. Using techniques of decomposition, truncation, and elimination with a computer algebra system, we first give qualitative proporties of all equilibria, and then analyze their saddle-node bifurcation and Hopf bifurcation both for real parameters and for integer' parameters. (C) 2002 Elsevier Science Ltd. All rights reserved.

With the rapid development of social media, the dissemination of health information has attracted more attention from people. To reveal the rule and mode of information diffusion path is the key to effective crisis prevention and control of information. In this paper, the team took the vaccine safety events as an example, selected and analyzed two hottest microblogs from each phase of one event. The team did visual analysis via Zhiwei which was one academic micro data analysis platform, and utilized social network analysis (SNA) to explore the propagating rules of public opinion.

A parameterization Hopf bifurcation controller is proposed for the equivalent nonlinear dynamic system of brushless DC motor, in this paper. The designed controller is consisted of vector field of the polynomial system and it is not change the equilibria of the original system. Compared with existing controllers, it is simpler and more general in form. Using the Hurwitz criterion and cylindrical algebraic decomposition (CAD), the controller parameters are calculated. Numerical simulations on the brushless DC motor system illustrate the effectiveness of the approach.

Previous reports only evaluated the correlation between oriented-attachment growth and part of the interaction, i.e., either van der Waals interaction or Coulombic interaction. By focusing on hexagonal nanorods, a relatively complex form of 1D nanocrystals, this article takes into account both dominant interactions and systematically investigates their countering effects on the separation dependence of the inter-particle interaction in the oriented-attachment growth of 1D nanocrystals. As elucidated by the Arrhenius equation, the growth kinetics and thermodynamics of oriented-attachment nanocrystals can thus be evaluated with such quantitatively resolved inter-particle interactions between the attaching objects.

This paper investigates robust simultaneous stabilization (RSS) control method for two port-controlled Hamiltonian (PCH) systems and proposes results on the design of simultaneous stabilization controller with parameters for such systems. Firstly, two PCH systems are studied. Using the dissipative Hamiltonian structural properties, the systems are combined to generate an augmented PCH system. When there are external disturbances in the systems, a robust controller with parameters is designed for the systems. Secondly, an algorithm for solving parameters of the controller is proposed with symbolic computation. Finally, an illustrative example is presented to show that the RSS controller obtained in this paper works very well.

In this paper, we investigate nonhomogeneous cubic differential systems with reversibility, which guarantees that the systems have a center at the origin. We apply the Ritt-Wu method to process algebraic equations and inequalities using Maple V.3 on a computer. We give an inductive algorithm for computing the period coefficient polynomials, we find the structure of solutions of systems of algebraic equations corresponding to isochronous centers and weak centers of every finite order, and we derive conditions on the parameters under which the origin is an isochronous center or a weak center of finite order. We show that with appropriate perturbations local bifurcation of critical periods will occur from weak centers of finite order and isochronous centers.

Background and Purpose.To present a novel helical TomoTherapy-based method for whole breast radiotherapy that has better dosimetry and also has acceptable low-dose regions for lungs, heart, and contralateral breast compared with tangential field-in-field IMRT (FIF-IMRT).Material and Methods.Ten patients with left-side breast cancer were planned with low-dose-area-constrained helical TomoTherapy (LDC-HT) and FIF-IMRT. Dosimetry was compared for all techniques.Results.Coverage of the whole breast was adequate with both techniques. Homogeneity index (HI) and conformity index (CI) were better with LDC-HT. LDC-HT showed dosimetry advantages over FIF-IMRT for ipsilateral lung and heart in not only high-dose levels but also in low-dose levels such asV10 GyandV5 Gy. For contralateral lung, both techniques can provide good protection, although the mean dose of LDC-HT is higher than that of FIF-IMRT.Conclusions.With LDC-HT, we obtained adequate target coverage, better HI and CI of target volume, better sparing of organs at risk, and acceptably low-dose areas compared with FIF-IMRT. LDC-HT could be a feasible method in whole breast radiotherapy. Clinical benefits of LDC-HT need further investigation.

The aim of this study was to investigate patterns and locations of lymph node metastasis in locally advanced cervical cancers. A total of 244 consecutive patients with stage IIb cervical cancer were retrospectively evaluated. Contrast-enhanced CT scans were used for lymph node grading. Lymph nodes with the shortest axis (>1 cm) were categorized as positive and those between 0.5 and 1 cm were categorized as suspicious. All lymph nodes (LNs) were also classified by their anatomic locations. Nine hundred thirty-one LNs (136 positive and 795 suspicious) were identified. Sixty-three (25.8%) patients had positive LNs, and 153 (62.7%) patients had only suspicious LNs. The metastatic pattern was predictable traveling from level 1 (external iliac, internal iliac, obturator, and mesorectum groups) through level 2 (common iliac and presacral groups) to level 3 (para-aortic groups). In most groups, LNs were located within 1.0 cm of main blood vessels. Our novel findings were: presacral LNs metastases were rare (2/244, 0.82%); the left common iliac group (LCI) had significantly more enlarged nodes than the right common iliac group (P = 0.00); the LCI and left down-para-aortic group were further away from blood vessels than expected (1.2 cm and 1.4 cm, respectively); no additional margin was needed in anterolateral direction for external iliac groups. The lymph node metastatic patterns are relatively predicable. Different expansions from vessels should be used to include LNs for different groups. Presacral nodes metastases are rare, and further study is warranted to see whether this region can be excluded from nodal CTV.

Patent evaluation is a multi-angle assessment system. Technology linkage is an important index in this system. By analyzing patents of medical endoscope and ultrasound therapy, especially the citation path of these patents, we got two types of technology linkages--citation tree and citation network. We found that in order to evaluate patent entirely, with different technology linkage, the evaluation method should be different. The conclusion is valuable to help for evaluating patent technology linkage entirely.

This paper considers the problem of robust fault-tolerant control for dissipative Hamiltonian systems subject to actuators' additive faults. An energy-based robust controller for the faulty system is proposed by using structure properties of dissipative Hamiltonian systems, which ensures the local uniform asymptotic stability and the disturbance attenuation performance of the faulty system. As compared to existing FTC strategies, the proposed strategies avoid solving the Lyapunov function associated with the nominal stabilizing strategy.

Without solving Hamilton-Jacobi-Issacs equations, a family of H ∞ controllers is proposed for dissipative Hamiltonian systems. These controllers are obtained by interconnecting an H ∞ controller with a generalized ZEG detectable, free generalized Hamiltonian system. Simulations show the effectiveness of the H ∞ control strategy proposed in this paper.