Risk assessment of organ transplant operation: A fuzzy hybrid MCDM approach based on fuzzy FMEA.

Nowadays, most fatal diseases are attributed to the malfunction of bodily. Sometimes organ transplantation is the only possible therapy, for instance for patients with end-stage liver diseases, and the preferred treatment, for instance for patients with end-stage renal diseases. However, this surgical procedure comes with inherent risks and effectively managing these risks to minimize the likelihood of complications arising from organ transplantation (maximizing life years from transplant and quality-adjusted life years) is crucial. To facilitate this process, risk ranking is used to identify and promptly address potential risks. Over recent years, considerable efforts have been made, and various approaches have been proposed to enhance Failure Modes and Effects Analysis (FMEA). In this study, taking into account the uncertainty in linguistic variables (F-FMEA), we introduce an approach based on Fuzzy Multi Criteria Decision Making (F-MCDM) for effectively evaluating scenarios and initial failure hazards. Nevertheless, the results of ranking failure modes generated by different MCDM methods may vary. This study is a retrospective study that suggests a comprehensive unified risk assessment model, integrating multiple techniques to produce a more inclusive ranking of failure modes. Exploring a broad spectrum of risks associated with organ transplant operations, we identified 20 principal hazards with the assistance of literature and experts. We developed a questionnaire to examine the impact of various critical factors on the survival of transplanted organs, such as irregularities in immunosuppressive drug consumption, inappropriate dietary habits, psychological disorders, engaging in strenuous activities post-transplant, neglecting quarantine regulations, and other design-related factors. Subsequently, we analyzed the severity of their effects on the durability of transplanted organs. Utilizing the Mamdani algorithm as a fuzzy inference engine and the Center of Gravity algorithm for tooling, we expressed the probability and severity of each risk. Finally, the failure mode ranking obtained from the F-FMEA method, three fuzzy MCDM methods, and the proposed combined method were identified. Additionally, the results obtained from various methods were evaluated by an expert team, demonstrating that the highest consistency and effectiveness among different methods are attributed to the proposed method, as it achieved a 91.67% agreement with expert opinions.

Spectral Bandedness in High-Fidelity Computational Fluid Dynamics Predicts Rupture Status in Intracranial Aneurysms.

Recent studies using high-fidelity computational fluid dynamics (CFD) have revealed high-frequency flow instabilities consistent with clinical reports of bruits and "musical murmurs", which have been speculated to contribute to aneurysm growth and rupture. We hypothesized that harmonic flow instabilities ("spectral bandedness") in aneurysm CFD data may be associated with rupture status. Before testing this hypothesis, we first present a novel method for quantifying and visualizing spectral bandedness in cardiovascular CFD datasets based on musical audio-processing tools. Motivated by previous studies of aneurysm hemodynamics, we also computed a selection of existing metrics that have demonstrated association with rupture in large studies. In a dataset of 50 bifurcation aneurysm geometries modeled using high-fidelity CFD, our spectral bandedness index (SBI) was the only metric significantly associated with rupture status (AUC = 0.76, p = 0.002), with a specificity of 79% (correctly predicting 19/24 unruptured cases) and sensitivity of 65% (correctly predicting 17/26 ruptured cases). Three-dimensional flow visualizations revealed coherent regions of high SBI to be associated with strong near-wall inflow jets and vortex-shedding/flutter phenomena in the aneurysm sac. We speculate that these intracycle, coherent flow instabilities may preferentially contribute to the progressive degradation of the aneurysm wall through flow-induced vibrational mechanisms, and that their absence in high-fidelity CFD may be useful for identifying intracranial aneurysms at lower risk of rupture.

Equity or Equality? Which Approach Brings More Satisfaction in a Kidney-Exchange Chain?

In United States (U.S.), government-funded organizations, such as NLDAC, reimburse travel and subsistence expenses incurred during living-organ donation process. However, in Iran, there is a non-governmental organization called Iranian Kidney Foundation (IKF) that funds the direct and indirect costs of donors through charitable donations and contributions from participants in the exchange program. In this article, for countries outside the U.S. that currently use an equality approach, we propose a potential new compensation-apportionment approach (equitable approach) for kidney-exchange chains and compare it with the currently available system (equality approach) in terms of the apportionment of compensation in a kidney-exchange chain to cover the expenses incurred by the initiating living donor of the chain in the act of donation. To this end, we propose a mechanism to apportion compensation among all participating pairs based on the equity approach by utilizing a prediction model to calculate the probability of graft survival in each transplant operation. These probabilities are then used to define the utility of any transplantation, considering the quality of each pair's donated and received kidney in the chain. Afterward, the corresponding cost is apportioned by a mechanism based on the normalized differences between the utility of donated and received kidneys for each incompatible pair of the chain. In summary, we demonstrate that by utilizing the equitable approach, there is more fairness and equity in the allocation of resources in organ-procurement systems, which results in more satisfaction among incompatible pairs. Additional future prospective studies are needed to assess this proposed equitable approach for kidney-exchange chains in countries outside the U.S., such as Iran, that currently use an equality approach.

Torrents of torment: turbulence as a mechanism of pulsatile tinnitus secondary to venous stenosis revealed by high-fidelity computational fluid dynamics.

BACKGROUND: Pulsatile tinnitus (PT) is a debilitating condition that can be caused by a vascular abnormality, such as an arterial or venous lesion. Although treatment of PT-related venous lesions has been shown to successfully cure patients of the associated 'tormenting' rhythmical sound, much controversy still exists regarding their role in the etiology of PT. METHODS: A patient presented with a history of worsening, unilateral PT. A partial venous sinus obstruction related to the large arachnoid granulation was detected on the right side, and subsequently stented at the right transverse sinus. High-fidelity computational fluid dynamics (CFD) was performed on a 3D model digitally segmented from the pre-stent venogram, with assumed pulsatile flow rates. A post-stent CFD model was also constructed from this. Data-driven sonification was performed on the CFD velocity data, blinded to the patient's self-reported sounds. RESULTS: The patient reported that the PT was completely resolved after stenting, and has had no recurrence of the symptoms after more than 2 years. CFD simulation revealed highly disturbed, turbulent-like flow at the sigmoid sinus close to auditory structures, producing a sonified audio signal that reproduced the subjective sonance of the patient's PT. No turbulence or sounds were evident at the stenosis, or anywhere in the post-stent model. CONCLUSIONS: For the first time, turbulence generated distal to a venous stenosis is shown to be a cause of PT. High-fidelity CFD may be useful for identifying patients with such 'torrents' of flow, to help guide treatment decision-making.

How patient-specific do internal carotid artery inflow rates need to be for computational fluid dynamics of cerebral aneurysms?

BACKGROUND: Computational fluid dynamics (CFD) has become a popular tool for studying 'patient-specific' blood flow dynamics in cerebral aneurysms; however, rarely are the inflow boundary conditions patient-specific. We aimed to test the impact of widespread reliance on generalized inflow rates. METHODS: Internal carotid artery (ICA) flow rates were measured via 2D cine phase-contrast MRI for 24 patients scheduled for endovascular therapy of an ICA aneurysm. CFD models were constructed from 3D rotational angiography, and pulsatile inflow rates imposed as measured by MRI or estimated using an average older-adult ICA flow waveform shape scaled by a cycle-average flow rate (Qavg) derived from the patient's ICA cross-sectional area via an assumed inlet velocity. RESULTS: There was good overall qualitative agreement in the magnitudes and spatial distributions of time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and spectral power index (SPI) using generalized versus patient-specific inflows. Sac-averaged quantities showed moderate to good correlations: R2=0.54 (TAWSS), 0.80 (OSI), and 0.68 (SPI). Using patient-specific Qavg to scale the generalized waveform shape resulted in near-perfect agreement for TAWSS, and reduced bias, but not scatter, for SPI. Patient-specific waveform had an impact only on OSI correlations, which improved to R2=0.93. CONCLUSIONS: Aneurysm CFD demonstrates the ability to stratify cases by nominal hemodynamic 'risk' factors when employing an age- and vascular-territory-specific recipe for generalized inflow rates. Qavg has a greater influence than waveform shape, suggesting some improvement could be achieved by including measurement of patient-specific Qavg into aneurysm imaging protocols.

On the spectrographic representation of cardiovascular flow instabilities.

In the past decade, high-fidelity computational fluid dynamics (CFD) has uncovered the presence of high-frequency flow instabilities (on the order of 100 s of Hz) in a variety of cardiovascular applications. These fluctuations are typically reported as pulsatile velocity-time traces or fast-Fourier-transformed power-frequency spectra, often from a single point or at most a handful of points. Originally inspired by its use in spectral Doppler ultrasound, here we demonstrate the utility of the simplest form of time-frequency representation - the spectrogram - as a more comprehensive yet still-intuitive means of visualizing the potential harmonic complexity of pulsatile cardiovascular flows. After reviewing the basic theory behind spectrograms, notably the short-time Fourier transform (STFT), we discuss the choice of input parameters that inform the appearance and trade-offs of spectrograms. We show that spectrograms using STFT were able to highlight spectral features and were representative of those obtained from more complex methods such as the Continuous Wavelet transforms (CWT). While visualization properties (colourmap, filtering, smoothing/interpolation) are shown to affect the conspicuity of spectral features, the window properties (function, size, overlap) are shown to have the greatest impact on the resulting spectrogram appearance. Using a set of cerebral aneurysm CFD cases, we show that spectrograms can readily reveal the case-specific nature of the time-varying flow instabilities, whether broadband, suggesting intermittent turbulent-like flow, or narrowband, suggesting laminar vortex shedding, or some combination thereof.

Presumed mast cell choroidal infiltrate in aggressive systemic mastocytosis.

PURPOSE: To report a rare case of a unilateral choroidal mast cell infiltration in a patient with aggressive systemic mastocytosis (ASM). OBSERVATIONS: The patient is a man in his fifties with a diagnosis of ASM. He developed visual complaints in the right eye associated with an area of subretinal fluid on fundus examination. Visual acuity at presentation was 20/150 in the right eye and 20/25 in the left eye. After ophthalmic and radiologic imaging workup, the patient was diagnosed with presumed choroidal mast cell infiltrate. The index of suspicion was high due to the prior ASM diagnosis. External beam radiation and intravitreal injection treatments were offered but the patient declined. The patient was switched from interferon to a new targeted systemic therapy for ASM, midostaurin. Despite some mixed, temporary response in systemic symptoms/signs of ASM at four months, the choroidal lesion and subretinal fluid were stable with visual acuity at 20/125. CONCLUSION AND IMPORTANCE: Mast cell choroidal infiltration in ASM should be considered as part of the differential with acute/subacute vision changes. Diagnosis requires exclusion of other possibilities with ocular imaging and in this case, monitoring for development of other malignancies in which there were none. Midostaurin's ocular response was not on par with systemic response. Additional localized ocular therapies may be required.

Modified Flanged Intrascleral Fixation of Intraocular Lens for Vitreoretinal Surgeons.

The surgeons have modified the flanged intrascleral intraocular lens (IOL) fixation technique initially described by Yamane et al. to avoid manipulation of the IOL within the anterior chamber. Their technique involves securing the IOL haptics into receiving needles within the posterior segment. Advantages of this technique include repositioning and securing a dislocated three-piece IOL to the sclera without removing the lens or creating a large corneal incision.

Management of Suture Penetration in Combined Vitrectomy and Scleral Buckle Surgery.

Purpose: To evaluate the surgical outcome of deep or full-thickness suture penetration during combined pars plana vitrectomy and scleral buckle (PPV/SB) surgery. Methods: Clinical data of patients who underwent PPV/SB for retinal detachment in our practice between June 2017 and April 2019 were reviewed. Cases with full-thickness scleral penetration were identified. Data including initial presentation, intraoperative complications, and management were collected. Long-term surgical outcome, complications, and recurrent detachment were determined. Results: Twenty-three cases with evidence of suture penetration were identified. In none of the cases the penetrated suture was visible in the subretinal space. The suture was replaced in cases with persistent leakage through the penetration site or when the surgical plan involved silicone oil insertion. Subretinal hemorrhage was noted during vitrectomy in 7 (30%) patients. The subretinal hemorrhage migrated to the macula in 2 (9%) cases and was drained through a posterior retinotomy. Retinal incarceration was noted in 4 (17%) cases and was released using a focal retinotomy in 2 (9%)cases to reattach the retina. Late complications included epiretinal membrane in 6 (26%) and recurrent detachment occurred in 2 (9%) patients. Final anatomical success was achieved in all patients. Conclusions: We propose new principles in the management of suture penetration during combined PPV/SB surgery. In the absence of a visible penetrated suture, suture replacement is required when there is profuse leakage through the penetration site or if silicone oil is used as tamponade. We recommend removal of submacular hemorrhage through a posterior retinotomy. The incarcerated retina can be flattened using release retinotomies.

4D-CT angiography versus 3D-rotational angiography as the imaging modality for computational fluid dynamics of cerebral aneurysms.

BACKGROUND AND PURPOSE: Computational fluid dynamics (CFD) can provide valuable information regarding intracranial hemodynamics. Patient-specific models can be segmented from various imaging modalities, which may influence the geometric output and thus hemodynamic results. This study aims to compare CFD results from aneurysm models segmented from three-dimensional rotational angiography (3D-RA) versus novel four-dimensional CT angiography (4D-CTA). METHODS: Fourteen patients with 16 cerebral aneurysms underwent novel 4D-CTA followed by 3D-RA. Endoluminal geometries were segmented from each modality using an identical workflow, blinded to the other modality, to produce 28 'original' models. Each was then minimally edited a second time to match length of branches, producing 28 additional 'matched' models. CFD simulations were performed using estimated flow rates for 'original' models (representing real-world experience) and patient-specific flow rates from 4D-CTA for 'matched' models (to control for influence of modality alone). RESULTS: Overall, geometric and hemodynamic results were consistent between models segmented from 3D-RA and 4D-CTA, with correlations improving after matching to control for operator-introduced variability. Despite smaller 4D-CTA parent artery diameters (3.49±0.97 mm vs 3.78±0.92 mm for 3D-RA; p=0.005) and sac volumes (157 (37-750 mm3) vs 173 (53-770 mm3) for 3D-RA; p=0.0002), sac averages of time-averaged wall shear stress (TAWSS), oscillatory shear (OSI), and high frequency fluctuations (measured by spectral power index, SPI) were well correlated between 3D-RA and 4D-CTA 'matched' control models (TAWSS, R2=0.91; OSI, R2=0.79; SPI, R2=0.90). CONCLUSIONS: Our study shows that CFD performed using 4D-CTA models produces reliable geometric and hemodynamic information in the intracranial circulation. 4D-CTA may be considered as a follow-up imaging tool for hemodynamic assessment of cerebral aneurysms.

A Eulerian method to analyze wall shear stress fixed points and manifolds in cardiovascular flows.

Based upon dynamical systems theory, a fixed point of a vector field such as the wall shear stress (WSS) at the luminal surface of a vessel is a point where the vector field vanishes. Unstable/stable manifolds identify contraction/expansion regions linking fixed points. The significance of such WSS topological features lies in their strong link with "disturbed" flow features like flow stagnation, separation and reversal, deemed responsible for vascular dysfunction initiation and progression. Here, we present a Eulerian method to analyze WSS topological skeleton through the identification and classification of WSS fixed points and manifolds in complex vascular geometries. The method rests on the volume contraction theory and analyzes the WSS topological skeleton through the WSS vector field divergence and Poincar[Formula: see text] index. The method is here applied to computational hemodynamics models of carotid bifurcation and intracranial aneurysm. An in-depth analysis of the time dependence of the WSS topological skeleton along the cardiac cycle is provided, enriching the information obtained from cycle-average WSS. Among the main findings, it emerges that on the carotid bifurcation, instantaneous WSS fixed points co-localize with cycle-average WSS fixed points for a fraction of the cardiac cycle ranging from 0 to [Formula: see text]; a persistent instantaneous WSS fixed point confined on the aneurysm dome does not co-localize with the cycle-average low-WSS region. In conclusion, the here presented approach shows the potential to speed up studies on the physiological significance of WSS topological skeleton in cardiovascular flows, ultimately increasing the chance of finding mechanistic explanations to clinical observations.

Multiple Aneurysms AnaTomy CHallenge 2018 (MATCH)-phase II: rupture risk assessment.

PURPOSE: Assessing the rupture probability of intracranial aneurysms (IAs) remains challenging. Therefore, hemodynamic simulations are increasingly applied toward supporting physicians during treatment planning. However, due to several assumptions, the clinical acceptance of these methods remains limited. METHODS: To provide an overview of state-of-the-art blood flow simulation capabilities, the Multiple Aneurysms AnaTomy CHallenge 2018 (MATCH) was conducted. Seventeen research groups from all over the world performed segmentations and hemodynamic simulations to identify the ruptured aneurysm in a patient harboring five IAs. Although simulation setups revealed good similarity, clear differences exist with respect to the analysis of aneurysm shape and blood flow results. Most groups (12/71%) included morphological and hemodynamic parameters in their analysis, with aspect ratio and wall shear stress as the most popular candidates, respectively. RESULTS: The majority of groups (7/41%) selected the largest aneurysm as being the ruptured one. Four (24%) of the participating groups were able to correctly select the ruptured aneurysm, while three groups (18%) ranked the ruptured aneurysm as the second most probable. Successful selections were based on the integration of clinically relevant information such as the aneurysm site, as well as advanced rupture probability models considering multiple parameters. Additionally, flow characteristics such as the quantification of inflow jets and the identification of multiple vortices led to correct predictions. CONCLUSIONS: MATCH compares state-of-the-art image-based blood flow simulation approaches to assess the rupture risk of IAs. Furthermore, this challenge highlights the importance of multivariate analyses by combining clinically relevant metadata with advanced morphological and hemodynamic quantification.

Optimal location of emergency stations in underground mine networks using a multiobjective mathematical model.

Background Every year, many mining accidents occur in underground mines all over the world resulting in the death and maiming of many miners and heavy financial losses to mining companies. Underground mining accounts for an increasing share of these events due to their special circumstances and the risks of working therein. Thus, the optimal location of emergency stations within the network of an underground mine in order to provide medical first aid and transport injured people at the right time, plays an essential role in reducing deaths and disabilities caused by accidents Objective The main objective of this study is to determine the location of emergency stations (ES) within the network of an underground coal mine in order to minimize the outreach time for the injured. Methods A three-objective mathematical model is presented for placement of ES facility location selection and allocation of facilities to the injured in various stopes. Results Taking into account the radius of influence for each ES, the proposed model is capable to reduce the maximum time for provision of emergency services in the event of accident for each stope. In addition, the coverage or lack of coverage of each stope by any of the emergency facility is determined by means of Floyd-Warshall algorithm and graph. To solve the problem, a global criterion method using GAMS software is used to evaluate the accuracy and efficiency of the model. Conclusions 7 locations were selected from among 46 candidates for the establishment of emergency facilities in Tabas underground coal mine.

Behavioral, Normative and Control Beliefs about Earthquake Preparedness: A Deductive Content Analysis Study.

INTRODUCTION: Despite efforts to increase earthquake preparedness (EP), the level of earthquake preparedness in Tehran is low, even when people acknowledge the risk they face. This problem has its roots in the beliefs of Tehran inhabitants about EP. This study is aimed to elicit the salient beliefs about earthquake preparedness among Tehran citizens. METHOD: This is a deductive content analysis research. The theory of planned behavior (TPB) has been applied as the theoretical framework of the study. 132 semi-structured interviews have been conducted with Tehran heads of households and the obtained data have been analyzed. RESULTS: The interviews showed that the belief in the usefulness of the EP and the belief that "the EP can cause anxiety among family members" were the salient behavioral beliefs (the ones influencing the attitude towards a behavior). The main normative belief (which influences the subjective norms), was "my family doesn't disagree with the EP" although most of the interviewees did not know about their families' views. Finally, the main control belief (which is the basis of perceived behavioral control), was that "education can facitilates EP". CONCLUSION:  Tehran inhabitants preparedness behaviors can be influenced by their behavioral, normative and control beliefs about preparedness. Recognition of these beliefs may assist policy makers and executives to develop a better understanding of the origins of the preparedness behaviors. Any interventions to change these behaviors should be made based on such knowledge. Key words: Earthquake; preparedness; salient beliefs; theory of planned behavior.

Individual movements and contact patterns in a Canadian long-term care facility.

Contact networks of individuals in healthcare facilities are poorly understood, largely due to the lack of spatio-temporal movement data. A better understanding of such networks of interactions can help improve disease control strategies for nosocomial outbreaks. We sought to determine the spatio-temporal patterns of interactions between individuals using movement data collected in the largest veterans long-term care facility in Canada. We processed close-range contact data generated by the exchange of ultra-low-power radio signals, in a prescribed proximity, between wireless sensors worn by the participants over a two-week period. Statistical analyses of contact and movement data were conducted. We found a clear dichotomy in the contact network and movement patterns between residents and healthcare workers (HCWs) in this facility. Overall, residents tend to have significantly more distinct contacts with the mean of 17.3 (s.d. 3.6) contacts, versus 3.5 (s.d. 2.3) for HCWs (p-value < 10-12), for a longer duration of time (with mean contact duration of 8 minutes for resident-resident pair versus 4.6 minutes for HCW-resident pair) while being less mobile than HCWs. Analysis of movement data and clustering coefficient of the hourly aggregated network indicates that the contact network is loosely connected (mean clustering coefficient: 0.25, interquartile range 0-0.40), while being highly structured. Our findings bring quantitative insights regarding the contact network and movements in a long-term care facility, which are highly relevant to infer direct human-to-human and indirect (i.e., via the environment) disease transmission processes. This data-driven quantification is essential for validating disease dynamic models, as well as decision analytic methods to inform control strategies for nosocomial infections.

Increased Reoperation Rate in Surgical Treatment of Rhegmatogenous Retinal Detachment with Coexistent Macular Hole.

PURPOSE: To examine the surgical outcomes in patients with coexistent macular hole (MH) and rhegmatogenous retinal detachment (RRD). DESIGN: Retrospective case series. PARTICIPANTS: All patients who underwent surgical repair of concomitant MH and retinal detachment (MHRD) between January 2014 and December 2016 in our facility were examined. At least 1 retinal break was noted in all MHRD cases. Exclusion criteria included MHRD related to high myopia without peripheral retinal tears. METHODS: Retrospective chart review. MAIN OUTCOME MEASURES: Data collected included presence of proliferative vitreoretinopathy (PVR) and classification at time of surgical repair, details of surgical repair including whether internal limiting membrane (ILM) peeling was achieved, type of ILM staining used, presence of retinal detachment (RD) in the fellow eye, and duration of follow-up. Outcomes evaluated included visual acuity comparisons, reoperation rate, final anatomic success, and MH closure rate. RESULTS: Over the study period, MHRD cases accounted for 17 of 745 (2.3%) of all repaired RDs in our practice. Proliferative vitreoretinopathy was present in 53% of MHRD cases. Reoperation rates for MHRD were significantly higher than our practice average for all RD repairs (29% vs. 9.7%; P = 0.01). Final anatomic success with RD was achieved in 100% of patients. Internal limiting membrane peeling was performed in 15 of 17 patients. Macular hole closure rate was 71% after initial surgery. Although 82% of patients experience equal or improved vision, only 24% of patients achieved visual acuity better than 20/80. Retinal detachment in the contralateral eye was noted in 3 of 16 patients (19%) included before initial presentation or during the follow-up period. CONCLUSIONS: Visual outcomes in MHRD cases were underwhelming because of high rates of presentation with PVR macula-off RRD, high reoperation rates, and relatively low MH closure rates. We suggest aggressive surgical techniques to repair MHRD.

The Theory of Planned Behavior and Disaster Preparedness.

INTRODUCTION: Disaster preparedness is defined as actions that ensure resources necessary to carry out an effective response are available before a disaster. Disaster preparedness requires a thorough understanding of the factors that influence performance or nonperformance of disaster preparedness behaviors (DPB). The major aim of this research was to further our understanding of DPB based on the theory of planned behavior (TPB). METHOD: This was a cross-sectional study of factors determining of DPB in a representative sample of 1233 Tehran inhabitants. Measures derived from the TPB were obtained in the unprepared and prepared people. RESULTS: Consistent with the theory, intentions to do DPB could the person predicted from attitudes, subjective norms, and perceived behavioral control with respect to DPB; and actually doing DPB was strongly related to intentions and perceptions of control assessed in the prepared people. Theoretical and practical implications of these findings are discussed. CONCLUSION: An effective intervention will not only have to encourage people of the desirability of DPB, but also to provide them with the skills and means to do it. The more strongly they can be made to feel that they have control over DPB, the more likely they are to carry out their intentions. That is, heightened perceived control tends to strengthen people's motivation to do DPB. KEY WORDS: theory of planned behavior; disaster;  preparedness.

The Effect of Individual Movements and Interventions on the Spread of Influenza in Long-Term Care Facilities.

BACKGROUND: Nosocomial influenza poses a serious risk among residents of long-term care facilities (LTCFs). OBJECTIVE: We sought to evaluate the effect of resident and staff movements and contact patterns on the outcomes of various intervention strategies for influenza control in an LTCF. METHODS: We collected contact frequency data in Canada's largest veterans' LTCF by enroling residents and staff into a study that tracked their movements through wireless tags and signal receivers. We analyzed and fitted the data to an agent-based simulation model of influenza infection, and performed Monte-Carlo simulations to evaluate the benefit of antiviral prophylaxis and patient isolation added to standard (baseline) infection control practice (i.e., vaccination of residents and staff, plus antiviral treatment of residents with symptomatic infection). RESULTS: We calibrated the model to attack rates of 20%, 40%, and 60% for the baseline scenario. For data-driven movements, we found that the largest reduction in attack rates (12.5% to 27%; ANOVA P < 0.001) was achieved when the baseline strategy was combined with antiviral prophylaxis for all residents for the duration of the outbreak. Isolation of residents with symptomatic infection resulted in little or no effect on the attack rates (2.3% to 4.2%; ANOVA P > 0.2) among residents. In contrast, parameterizing the model with random movements yielded different results, suggesting that the highest benefit was achieved through patient isolation (69.6% to 79.6%; ANOVA P < 0.001) while the additional benefit of prophylaxis was negligible in reducing the cumulative number of infections. CONCLUSIONS: Our study revealed a highly structured contact and movement patterns within the LTCF. Accounting for this structure-instead of assuming randomness-in decision analytic methods can result in substantially different predictions.

Salient Public Beliefs Underlying Disaster Preparedness Behaviors: A Theory-Based Qualitative Study.

Introduction Given the increasing importance of disaster preparedness in Tehran, the capital of Iran, interventions encouraging disaster preparedness behavior (DPB) are needed. This study was conducted to show how an elicitation method can be used to identify salient consequences, referents, and circumstances about DPB and provide recommendations for interventions and quantitative research. METHOD: A theory-based qualitative study using a semi-structured elicitation questionnaire was conducted with 132 heads of households from 22 districts in Tehran, Iran. Following the Theory of Planned Behavior (TPB), six open-ended questions were used to record the opinion of people about DPB: advantages of engaging in DPB; disadvantages of doing so; people who approve; people who disapprove; things that make it easy; and things that make it difficult. Content analysis showed the categories of salient consequences, reference groups, and circumstances. RESULTS: The three most frequently mentioned advantages obtained from inhabitants of Tehran were health outcomes (eg, it helps us to save our lives, it provides basic needs, and it protects us until relief workers arrive); other salient advantages were mentioned (eg, helps family reunification). The main disadvantage was preparedness anxiety. Family members were the most frequently mentioned social referent when people were asked who might approve or disapprove of their DPB. The two main circumstances perceived to obstruct DPB included not having enough knowledge or enough time. CONCLUSION: The results of this qualitative study suggest that interventions to encourage DPB among Tehran inhabitants should address: perceived consequences of DPB on health and other factors beyond health; barriers of not having enough knowledge and time perceived to hinder DPB; and social approval. More accurate research on salient beliefs with close-ended items developed from these open-ended data and with larger sample sizes of Tehran inhabitants is necessary. Research with other stakeholder groups is needed to understand their perceptions about DPB in creating the people's social environment. Najafi M , Ardalan A , Akbarisari A , Noorbala AA , Elmi H . Salient public beliefs underlying disaster preparedness behaviors: a theory-based qualitative study. Prehosp Disaster Med. 2017;32(2):124-133 .

Spectral Hole Burning in Cyanobacterial Photosystem I with P700 in Oxidized and Neutral States.

We explored the rich satellite hole structures emerging as a result of spectral hole burning in cyanobacterial photosystem I (PSI) and demonstrated that hole burning properties of PSI, particularly at high resolution, are strongly affected by the oxidation state of the primary donor P700, as P700+ effectively quenches the excitations of the lowest-energy antenna states responsible for fluorescence. Obtaining better control of this variable will be crucial for high-resolution ensemble experiments on protein energy landscapes in PSI. The separate nonphotochemical spectral hole burning (NPHB) signatures of various red antenna states were obtained, allowing for additional constraints on excitonic structure-based calculations. Preliminary evidence is presented for an additional red state of PSI of T. elongatus peaked at 712.6 nm, distinct from previously reported C708 and C715 states and possibly involving chlorophyll B15. Excitation at wavelengths as long as 800 nm results in charge separation at cryogenic temperatures in PSI also in Synechocystis sp. PCC 6803. Both the "P700+ minus P700" holes and nonphotochemical spectral holes were subjected to thermocycling. The distribution of barriers manifesting in recovery of the "P700+ minus P700" signature contains two components in sample-dependent proportions, likely reflecting the percentages of FA and FB clusters being successfully prereduced before the optical experiment. The barrier distribution for the recovery of the lower-energy nonphotochemical spectral holes resembles those observed for other pigment-protein complexes, suggesting similar structural elements are responsible for NPHB. Higher-energy components exhibit evidence of "domino effects" such as shifts of certain bands persisting past the lower-energy hole recovery. Thus, conformational changes triggered by excitation of one pigment likely can affect multiple pigments in this tightly packed system.