Decision-making analysis in cooperative environments for decentralized cognitive radio networks

Currently, there are saturated frequency bands that affect the quality of service for new users. Cognitive radio provides an alternative solution to this problem through dynamic spectrum access. However, the solutions proposed in the current literature are focused on a centralized network and do not allow demonstrating the behavior in a multi-user environment, much less the effect that cooperation between secondary users can have. This article establishes a decision-making model for the best spectral opportunity selection with a cooperative approach in decentralized cognitive radio networks and contrasts its results with three multi-criteria decision-making algorithms: SAW, TOPSIS, and VIKOR. So, this research suggests a cooperative decision-making model based on four main modules. (1) a collaborative module for the exchange of information between SU; (2) a module for PU characterization; (3) a module of the probability of SU arrival; and (4) the SO feedback selection module. The results are obtained through simulations fed with experimental spectral occupancy data captured in a measurement campaign. Handoff and throughput were used as evaluation metrics, along with five levels of collaboration: 10%, 20%, 50%, 80%, and 100%, and eight different scenarios based on the type of network: GSM and Wi-Fi, the application type: real-time and best-effort, and the level of traffic: high and low. The contribution of this study lies in the fact that no current work includes the following relevant aspects for an adequate validation and evaluation of this proposal: First, the consideration of a decentralized cognitive radio network; second, the decision-making with cooperative strategies; third, different techniques for SO selection; fourth, the validation and evaluation with experimental spectral occupancy data captured in measurement campaigns; finally, the performance analysis in diverse networks, traffic levels, and types of applications.

Enhanced Automatic Segmentation for Superficial White Matter Fiber Bundles for Probabilistic Tractography Datasets

This paper presents an enhanced algorithm for automatic segmentation of superficial white matter (SWM) bundles from probabilistic dMRI tractography datasets, based on a multi-subject bundle atlas. Previous segmentation methods use the maximum Euclidean distance between corresponding points of the subject fibers and the atlas centroids. However, this scheme might include noisy fibers. Here, we propose a three step approach to discard noisy fibers improving the identification of fibers. The first step applies a fiber clustering and the segmentation is performed between the centroids of the clusters and the atlas centroids. This step removes outliers and enables a better identification of fibers with similar shapes. The second step applies a fiber filter based on two different fiber similarities. One is the Symmetrized Segment-Path Distance (SSPD) over 2D ISOMAP and the other is an adapted version of SSPD for 3D space. The last step eliminates noisy fibers by removing those that connect regions that are far from the main atlas bundle connections. We perform an experimental evaluation using ten subjects of the Human Connectome (HCP) database. The evaluation only considers the bundles connecting precentral and postcentral gyri, with a total of seven bundles per hemisphere. For comparison, the bundles of the ten subjects were manually segmented. Bundles segmented with our method were evaluated in terms of similarity to manually segmented bundles and the final number of fibers. The results show that our approach obtains bundles with a higher similarity score than the state-of-the-art method and maintains a similar number of fibers.Clinical relevance-Many brain pathologies or disorders can occur in specific regions of the SWM automatic segmentation of reliable SWM bundles would help applications to clinical research.

Distribution of Burkholderia cepacia complex species isolated from industrial processes and contaminated products in Argentina

Burkholderia cepacia complex (Bcc) members have clinical relevance as opportunistic pathogens in patients with cystic fibrosis and are responsible of numerous nosocomial infections. These closely related bacteria are also reported as frequent contaminants of industrial products. In this retrospective study, we use PCR and recA gene sequence analysis to identify at species level Bcc isolates recovered from massive consumption products and industrial processes in Argentina during the last 25 years. The sequences obtained were also compared with recA sequences from clinical Bcc isolates deposited in GenBank database. We detected Bcc in purified water and preserved products from pharmaceutics, cosmetics, household cleaning articles, and beverages industries. B. contaminans (which is prevalent among people with cystic fibrosis in Argentina) was the most frequent Bcc species identified (42% of the Bcc isolates studied). B. cepacia (10%), B. cenocepacia (5%), B. vietnamiensis (16%), B. arboris (3%), and the recently defined B. aenigmatica (24%) were also detected. Rec A sequences from all B. cepacia and most B. contaminans industrial isolates obtained in this study displayed 100% identity with recA sequences from isolates infecting Argentinean patients. This information brings evidence for considering industrial massive consumption products as a potential source of Bcc infections. In addition, identification at species level in industrial microbiological laboratories is necessary for a better epidemiological surveillance. Particularly in Argentina, more studies are required in order to reveal the role of these products in the acquisition of B. contaminans infections.

The effect of hybrid zinc oxide/graphene oxide (ZnO/GO) nano-catalysts on the photocatalytic degradation of simazine

The photocatalytic degradation of simazine (SIM) was investigated using zinc oxide/graphene oxide (ZnO/GO) composite materials under visible light irradiation. The reaction kinetics was studied to optimize the reaction parameters for efficient degradation of SIM. Batch studies were performed to investigate the effects of initial reaction pH, the loading of the ZnO onto GO, and mass of catalyst on the removal of SIM from aqueous solution. A pH of 2 was determined to be the optimal reaction pH for the different ZnO-loaded GO catalysts. In addition, a mass of 40 mg of catalyst in the reaction was observed to be the most effective for the catalysts synthesized using 20 and 30 mmol of Zn²⁺ ions; whereas a mass of 10 mg was most effective for the ZnO/GO composite material synthesized using 10 mmol Zn²⁺ ions. The reaction was observed to follow a second-order kinetics for the degradation process. Furthermore, the synthesized ZnO/GO composite catalysts resulted in higher reaction rates than those observed for pure ZnO. The 30 mmol ZnO/GO composite expressed a rate of SIM degradation ten times greater than the rate observed for pure ZnO, and sixty-two times greater than the rate of photolysis. In addition, the catalyst cycling exhibited a constant photocatalytic activity for the ZnO/GO composite over three reaction cycles without the need of a conditioning cycle.

Beyond the bladder: poor sleep in women with overactive bladder syndrome

BACKGROUND

Nocturnal bladder symptoms and sleep disruption commonly coexist in middle-aged and older women. Although sleep disruption is often attributed to nocturnal bladder symptoms in women with overactive bladder syndrome, nonbladder factors also may influence sleep in this population. Many women with overactive bladder are eager to identify nonpharmacologic strategies for both bladder symptoms and sleep disruption, given the potential adverse effects of sedative and anticholinergic bladder medications in this population.

OBJECTIVES

To provide greater insight into the complex relationship between nighttime overactive bladder symptoms and sleep disruption, and to evaluate the effects of a guided slow-paced respiration intervention on sleep outcomes in women with overactive bladder.

STUDY DESIGN

We conducted an ancillary study within a randomized trial of slow-paced respiration in women with overactive bladder symptoms. Ambulatory community-dwelling women who reported ≥3 episodes/day of urgency-associated voiding or incontinence were randomized to use either a portable biofeedback device (RESPeRATE; Intercure, Ltd) to practice guided slow-paced respiration exercises daily for 12 weeks (N=79) or an identical-appearing device programmed to play nonrhythmic music without guiding breathing (N=82). At baseline and after 12 weeks, bladder symptoms were assessed by voiding diary, sleep duration, and disruption were assessed by sleep diary corroborated by wrist actigraphy, and poor sleep quality was determined by a Pittsburgh Sleep Quality Index global score >5.

RESULTS

Of the 161 women randomized, 31% reported at least twice-nightly nocturia, 26% nocturnal incontinence, and 70% poor sleep quality at baseline. Of the 123 reporting any nighttime awakenings, 89% averaged 1 or more nighttime awakenings, and 83% attributed at least half of awakenings to using the bathroom. Self-reported wake time after sleep onset increased with increasing frequency of nocturnal bladder symptoms (P=.01 for linear trend). However, even among women without nocturia, average sleep quality was poor (Pittsburg Sleep Quality Index global score mean of 7.3; 95% confidence interval, 6.0-8.6). Over 12 weeks, women assigned to slow-paced respiration (N=79) experienced modest improvements in mean nocturnal voiding frequency (0.4 fewer voids/night), sleep quality (1.1 point score decrease), and sleep disruption (1.5% decreased wake time after sleep onset). However, similar improvements were detected in the music control group (N=81), without significant between-group differences.

CONCLUSIONS

Many women with overactive bladder syndrome experience disrupted sleep, but not all nocturnal awakenings are attributable to bladder symptoms, and average sleep quality tends to be poor even in women without nocturia. Findings suggest that clinicians should not assume that poor sleep in women with overactive bladder syndrome is primarily caused by nocturnal bladder symptoms. Guided slow-paced respiration was associated with modest improvements in nocturia frequency and sleep quality in this trial, but the results do not support clinician recommendation to use this technique over other behavioral relaxation techniques for improving sleep.

Online ratings of spinal deformity surgeons: analysis of 634 surgeons

STUDY DESIGN

Observational study.

OBJECTIVE

To evaluate the online ratings of spine deformity surgeons and variables that may affect online ratings Physician review websites (PRW) continue to be an emerging trend in the US across all specialties. Previous literature with smaller sample sizes revealed that most spine surgeons are rated on at least on PRW. To date, the online ratings of spinal deformity surgeons have not been evaluated.

MATERIALS AND METHODS

A review of the 2017 Scoliosis Research Society (SRS) Fellowship directory for active fellows and candidate members yielded 634 active members. Online ratings from five PRWs were recorded and scaled from 0 to 100. Using SPSS, one-way analysis of variance was used to compare differences between multiple groups. A t test was used to compare differences between two groups. Significance was set at p < 0.05.

RESULTS

Most surgeons (98.7%) were rated on at least one PRW. Surgeons in academic or hospital practice had higher ratings than those in private practice (83.4 vs. 78.8, and 83.7 vs. 78.8, p < 0.001). Surgeons with 0-5-year experience had higher ratings than more experienced surgeons (p < 0.001). However, surgeons in practice for 0-5 years also had fewer reviews than their more experienced colleagues (p < 0.05). We found no differences in ratings based on sex, specialty, or region. The largest differences in ratings between high and poorly rated spine surgeons was in areas pertaining to the doctor-patient relationship (answering questions, time spent with the patient).

CONCLUSION

The majority (98.7%) of SRS surgeons are rated on at least one PRW. SRS surgeons in practice between 0 and 5 years have higher ratings than more experienced surgeons, but were rated by fewer patients than their more experienced counterparts. Higher ratings were associated with variables pertaining to the patient-doctor relationship.

LEVEL OF EVIDENCE

IV.

Evaluation of the VIDAS Staph Enterotoxin II (SET 2) Immunoassay Method for the Detection of Staphylococcal Enterotoxins in Selected Foods: Collaborative Study

A multilaboratory study was conducted to determine the limit of detection (LOD) of Staphylococcal enterotoxins (SET) in 5 foods. Cooked chicken, ham, potato salad, pasteurized liquid whole milk, and canned mushrooms were each spiked with a different enterotoxin (A, B, C1, D, or E), and tested at 0.25 and 0.5 ng/g SET levels to determine the LOD of the assay for those foods in a collaborative study. Unspiked controls were also included. A total of 19 laboratories representing government and industry participated. In this study, 1674 test portions were analyzed, of which 1638 were used in the statistical analysis. Of the 1638 test portions used in the statistical analysis, 1104 were spiked test portions, of which 1073 were positive by the VIDAS Staph enterotoxin II (SET 2) method. The detection rates at the 0.25 ng/mL level were cooked chicken, 98.2; ham, 99.0; potato salad, 99.1; liquid whole milk, 85.2; and canned mushrooms, 100. The detection rates at the 0.5 ng/mL level were cooked chicken, 97.4; ham, 98.1; potato salad, 100; liquid whole milk, 99.0; and canned mushrooms, 100. The data indicate that the SET 2 method is capable of detecting SET at 0.25 ng/g in cooked chicken, ham, potato salad, and canned mushrooms and at 0.5 ng/g in pasteurized liquid whole milk.

Enumeration of Total Aerobic Microorganisms in Foods by SimPlate® Total Plate Count–Color Indicator Methods and Conventional Culture Methods: Collaborative Study

The relative efficacy of the SimPlate® Total Plate Count–Color Indicator (TPC–CI) method (SimPlate 35°C) was compared with the AOAC Official Method 966.23 (AOAC 35°C) for enumeration of total aerobic microorganisms in foods. The SimPlate TPC–CI method, incubated at 30°C (SimPlate 30°C), was also compared with the International Organization for Standardization (ISO) 4833 method (ISO 30°C). Six food types were analyzed: ground black pepper, flour, nut meats, frozen hamburger patties, frozen fruits, and fresh vegetables. All foods tested were naturally contaminated. Nineteen laboratories throughout North America and Europe participated in the study. Three method comparisons were conducted. In general, there was &lt;0.3 mean log count difference in recovery among the SimPlate methods and their corresponding reference methods. Mean log counts between the 2 reference methods were also very similar. Repeatability (sr) and reproducibility (sR) standard deviations were similar among the 3 method comparisons. The SimPlate method (35°C) and the AOAC method were comparable for enumerating total aerobic microorganisms in foods. Similarly, the SimPlate method (30°C) was comparable to the ISO method when samples were prepared and incubated according to the ISO method.

Visual Immunoprecipitate Assay Eight Hour Method for Detection of Enterohemorrhagic Escherichia coli O157:H7 in Raw and Cooked Beef (Modification of AOAC Official Method 996.09): Collaborative Study

AOAC Official Method 996.09, Visual Immunoprecipitate Assay (VIP®) for Escherichia coli O157:H7, was modified to incorporate a new enrichment protocol using BioControl EHEC8™ medium for testing raw and cooked beef. Foods were tested by VIP assay and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) enrichment procedure and the FDA Bacteriological Analytical Manual (BAM) isolation and confirmation techniques. A total of 15 collaborators participated. Raw and cooked ground beef were inoculated with E. coli O157:H7 at 2 different levels: a high level, where predominantly positive results were expect d, and a low level where fractional recovery was anticipated. Collaborators tested 396 test portions and controls by both methods, for a total of 792 test portions. Of the 396 paired test portions, 75 were positive and 230 were negative by both the VIP and culture methods. Eleven test portions were presumptively positive by VIP and could not be confirmed culturally; 32 were negative by VIP, but confirmed positive by culture; and 65 were negative by the culture method, but confirmed positive by the VIP method. There was no statistical difference between results obtained with the VIP for EHEC 8 h method and the culture method except for cooked beef, where the VIP had significantly higher recovery for one inoculation level.

Assurance® Enzyme Immunoassay Eight Hour Method for Detection of Enterohemorrhagic Escherichia coli O157:H7 in Raw and Cooked Beef (Modification of AOAC Official Method 996.10): Collaborative Study

AOAC Official Method 996.10, Assurance® Enzyme Immunoassay (EIA) for Escherichia coli O157:H7 (EHEC), was modified to incorporate a new enrichment protocol using BioControl EHEC8™ medium for testing raw and cooked beef. Foods were tested by EIA and the U.S. Department of Agriculture/Food Safety and Inspection Service (USDA/FSIS) enrichment conditions and the FDA Bacteriological Analytical Manual (BAM) isolation and confirmation techniques. A total of 14 collaborators participated. Raw and cooked ground beef were inoculated with E. coli O157:H7 at 2 different levels: a high level where predominantly positive results were expected, and a low level where fractional recovery was anticipated. Collaborators tested 378 test portions and controls by both the 8 h EIA and the USDA/FSIS enrichment methods, for a total of 756 test portions. Of the 378 paired test portions, 75 were positive and 212 were negative by both methods. Thirteen test portions were presumptively positive by EIA and could not be confirmed culturally; 30 were negative by EIA, but confirmed positive by culture; and 65 were negative by the culture method, but confirmed positive by the EIA method. There was no statistical difference between results obtained with the Assurance EIA for EHEC 8 h method and the culture method for raw ground beef. The Assurance EIA had a significantly higher recovery for cooked beef.

Outcomes of Halo Immobilization for Cervical Spine Fractures

STUDY DESIGN

Retrospective.

OBJECTIVES

To evaluate complications and outcomes of halo immobilization in patients with cervical spine fractures treated at a level I trauma center.

METHODS

A retrospective evaluation of patients treated at a single institution with halo immobilization from August 2000 to February 2016 was performed. Demographic information, mechanism of injury, level and type of spine fracture, length of halo immobilization, complications associated with halo immobilization, and length of patient follow-up were collected.

RESULTS

A total of 189 patients treated with halos were identified. Of the 189 patients, 121 (64%) received halos for the management of cervical spine fractures and were included in the study. A total of 49.6% were males and 50.4% were females. The average age was 50.8 years (range 1-89 years). Overall, 10.7% sustained C1 fractures, 71.1% C2 fractures, and 18.2% subaxial spine (C3-C7) fractures. In all, 47.1% of the upper cervical fractures were either odontoid or hangman-type fractures. A total of 25.1% of patients had multiple cervical fractures. At latest follow-up, 81% had healed fractures with good alignment, minimal pain, and return to normal activities. There was an 8.3% mortality rate. The mortality group had an average age of 64.7 years (range 19-84 years). A total of 10.7% of patients failed halo immobilization and 46.3% of patients had complications such as pin site infections (5.8%), loose pins (1.7%), neck pain (20.7%), decreased range of motion (14%), thoracic skin ulcers (2.4%), and dysphagia (1.7%).

CONCLUSIONS

The use of halo immobilization for cervical spine fractures resulted in clinical success in 81% of patients. Complication rates in geriatric patients were lower than previously reported in the literature.

Acute kidney injury after cardiac surgery: prevalence, impact and management challenges

Acute kidney injury (AKI) is a major medical problem that is of particular concern after cardiac surgery. Perioperative AKI is independently associated with an increase in short-term morbidity, costs of treatment, and long-term mortality. In this review, we explore the definition of cardiac surgery-associated acute kidney injury (CSA-AKI) and identify diverse mechanisms and risk factors contributing to the renal insult. Current theories of the pathophysiology of CSA-AKI and description of its clinical course will be addressed in this review. Data on the most promising renal protective strategies in cardiac surgery, from well-designed studies, will be scrutinized. Furthermore, diagnostic tools such as novel biomarkers of AKI and their potential utility will be discussed.

Surgical approach significantly affects the complication rates associated with total hip arthroplasty

AIMS

A variety of surgical approaches are used for total hip arthroplasty (THA), all with reported advantages and disadvantages. A number of common complications can occur following THA regardless of the approach used. The purpose of this study was to compare five commonly used surgical approaches with respect to the incidence of surgery-related complications.

PATIENTS AND METHODS

The electronic medical records of all patients who underwent primary elective THA at a single large-volume arthroplasty centre, between 2011 and 2016, with at least two years of follow-up, were reviewed. After exclusion, 3574 consecutive patients were included in the study. There were 1571 men (44.0%) and 2003 women (56.0%). Their mean age and body mass index (BMI) was 63.0 years (sd 11.8) and 29.1 kg/m² (sd 6.1), respectively. Data gathered included the age of the patient, BMI, the American Society of Anesthesiologists (ASA) score, estimated blood loss (EBL), length of stay (LOS), operating time, the presence of intra- or postoperative complications, type of complication, and the surgical approach. The approaches used during the study were posterior, anterior, direct lateral, anterolateral, and the northern approach. The complications that were recorded included prolonged wound drainage without infection, superficial infection, deep infection, dislocation, aseptic loosening, and periprosthetic fracture. Finally, the need for re-operation was recorded. Means were compared using analysis of variance (ANOVA) and Student's t-tests where appropriate and proportions were compared using the chi-squared test.

RESULTS

A total of 248 patients had 263 complications related to the surgery, with an incidence of 6.94%. The anterior approach had the highest incidence of complications (8.5% (113/1329)) and the posterior approach had the lowest, at 5.85% (97/1657; p = 0.006). Most complications were due to deep infection (22.8%), periprosthetic fracture (22.4%), and prolonged wound drainage (21.3%). The rate of dislocation was 0.84% (14/1657) with the posterior approach and 1.28% (17/1329) with the anterior approach (p = 0.32).

CONCLUSION

Overall, THA has a relatively low complication rate. However, the surgical approach plays a role in the incidence of complications. We found that the posterior approach had a significantly lower overall complication rate compared with the anterior approach, with an equal dislocation rate. Periprosthetic fracture and surgical site infection contributed most to the early complication rates. Cite this article: Bone Joint J 2019;101-B:646-651.

Adsorption of methylene blue and tetracycline onto biomass-based material prepared by sulfuric acid reflux

The adsorptive removal of environmental pollutants is an effective method for the treatment of contaminated water. Thus, the preparation of adsorbents from low-cost, readily available, and renewable resources has garnered immense attention in recent years. In this study, a facile one-step method for the preparation of a high-capacity adsorbent is demonstrated by refluxing pine cones in concentrated sulfuric acid. With sulfuric acid reflux, the pine cones undergone carbonization as well as functionalization with sulfonic acid groups. The adsorbent demonstrated high adsorption capacity for two emerging organic pollutants, methylene blue (MB) and tetracycline (TC). Different variables such as pH, temperature, contact time, and initial concentration of the pollutants were analyzed and showed that the adsorption capacity for MB increased in a basic pH and vice versa for TC. Also, the elevated temperature favored the adsorption for both MB and TC. The maximum adsorption capacity was found to be 1666.66, and 357.14 mg g⁻¹ for MB and TC, respectively. In comparison to the pristine pine cone, the sulfuric acid treated pine cone demonstrated an extraordinary improvement in the adsorption capacity. The adsorption of MB and TC was performed from the tap water matrix and similar adsorption capacities were found. A packed glass column was also prepared to demonstrate the adsorption of MB from tap water under flow conditions.

Facile conversion of pine cones into a high-capacity adsorbent for the removal of methylene blue and tetracycline from water.

Ascariasis as cause of intestinal occlusion and concurrent appendicitis

Intestinal occlusion by ascariasis is a commonly seen socio-economic status low, is associated with poor sanitary hygiene. It is rare to see a case with both intestinal occlusion and appendicitis at the same time, as described in this report.

Making sense of the relationships between Ne, Nb and Nc towards defining conservation thresholds in Atlantic salmon (Salmo salar)

Effective population size over a generation (Ne) or over a reproductive cycle (Nb) and the adult census size (Nc) are important parameters in both conservation and evolutionary biology. Ne provides information regarding the rate of loss of genetic diversity and can be tracked back in time to infer demographic history of populations, whereas Nb may often be more easily quantified than Nc for short-term abundance monitoring. In this study, we propose (1) an empirical context to Waples et al. (2014) who introduced a correction to bias due to overlapping generations, and (2) a mathematical relationship between Ne and Nb for direct application in Atlantic salmon populations in Québec, Canada. To achieve this, we investigate the relationships between Ne, Nb and Nc in 10 Atlantic salmon populations, Canada, for which we genotyped 100 randomly sampled young-of-the year individuals for 5 consecutive years. The results show a positive correlation between Ne, Nb and Nc, suggesting that Nb is an indicative parameter for tracking effective population size and abundance of Atlantic salmon. However, our model allows predicting Nc from Nb values at 27% that can be partly explained by high variance in Nb/Nc both among populations (37%) and among years (19%). This result illustrates the need for thorough calibration of Nb/Nc before using Nb in monitoring programs, as well as a full understanding of the limits of such an approach. Finally, we discuss the importance of these results for the management of wild populations.

THE CHALLENGE OF CIEMAT INTERNAL DOSIMETRY SERVICE FOR ACCREDITATION ACCORDING TO ISO/IEC 17025 STANDARD, FOR IN VIVO AND IN VITRO MONITORING AND DOSE ASSESSMENT OF INTERNAL EXPOSURES

The accreditation of an Internal Dosimetry Service (IDS) according to ISO/IEC 17025 Standard is a challenge. The aim of this process is to guarantee the technical competence for the monitoring of radionuclides incorporated in the body and for the evaluation of the associated committed effective dose E(50). This publication describes the main accreditation issues addressed by CIEMAT IDS regarding all the procedures involving good practice in internal dosimetry, focussing in the difficulties to ensure the traceability in the whole process, the appropriate calculation of detection limit of measurement techniques, the validation of methods (monitoring and dose assessments), the description of all the uncertainty sources and the interpretation of monitoring data to evaluate the intake and the committed effective dose.

Novel association between serum pentraxin-2 levels and advanced fibrosis in well-characterised patients with non-alcoholic fatty liver disease

BACKGROUND

Pentraxin-2 (PTX-2), a serum protein, inhibits inflammation and fibrosis, and recombinant PTX-2 is being tested as an anti-fibrotic agent.

AIM

To evaluate the association between serum PTX-2 levels and fibrosis stage in patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

Serum pentraxin-2 levels were compared between four groups of well-characterised patients including NAFLD with no fibrosis, NAFLD with mild-moderate fibrosis (stage 1-2), NAFLD with advanced fibrosis (stage 3-4), and age-sex matched non-NAFLD controls.

RESULTS

Sixty subjects were included in the study. The mean age was 58.9 years, 68% were male and 58% were Caucasian. In univariate analysis, serum PTX-2 levels significantly decreased from non-NAFLD controls to mild NAFLD with no fibrosis, to NAFLD with mild-moderate fibrosis and were lowest in patients with NAFLD and advanced fibrosis, in a dose-dependent manner (P < 0.0001). In multivariable-adjusted analyses controlling for age, sex, albumin, and CRP, the results remained consistent and statistically significant. Serum PTX-2 level had an AUROC of 0.84 (95% CI: 0.71-0.97) for the diagnosis of NAFLD, and an AUROC of 0.77 (95% CI: 0.65-0.90) for the diagnosis of advanced fibrosis in NAFLD. Serum PTX-2 levels also decreased with increasing liver stiffness as estimated by magnetic resonance elastography (r = -0.31, P = 0.02).

CONCLUSIONS

PTX-2 levels are significantly lower in patients with NAFLD compared to non-NAFLD controls, and decline further in patients with advanced fibrosis. PTX-2 may therefore be both a biomarker of disease and a potential target for anti-fibrotic therapy with the recombinant pentraxin-2.

Reconnection with the Ideal Tree: A New Approach to Real-Time Search

Many applications, ranging from video games to dynamic robotics, require solving single-agent, deterministic search problems in partially known environments under very tight time constraints. Real-Time Heuristic Search (RTHS) algorithms are specifically designed for those applications. As a subroutine, most of them invoke a standard, but bounded, search algorithm that searches for the goal. In this paper we present FRIT, a simple approach for single-agent deterministic search problems under tight constraints and partially known environments that unlike traditional RTHS does not search for the goal but rather searches for a path that connects the current state with a so-called ideal tree T . When the agent observes that an arc in the tree cannot be traversed in the actual environment, it removes such an arc from T and then carries out a reconnection search whose objective is to find a path between the current state and any node in T . The reconnection search is done using an algorithm that is passed as a parameter to FRIT. If such a parameter is an RTHS algorithm, then the resulting algorithm can be an RTHS algorithm. We show, in addition, that FRIT may be fed with a (bounded) complete blind-search algorithm. We evaluate our approach over grid pathfinding benchmarks including game maps and mazes. Our results show that FRIT, used with RTAA*, a standard RTHS algorithm, outperforms RTAA* significantly; by one order of magnitude under tight time constraints. In addition, FRIT(daRTAA*) substantially outperforms daRTAA*, a state-of-the-art RTHS algorithm, usually obtaining solutions 50% cheaper on average when performing the same search effort. Finally, FRIT(BFS), i.e., FRIT using breadth-first-search, obtains best-quality solutions when time is limited compared to Adaptive A* and Repeated A*. Finally we show that Bug2, a pathfinding-specific navigation algorithm, outperforms FRIT(BFS) when planning time is extremely limited, but when given more time, the situation reverses.

Effect of a low-flatulogenic diet in patients with flatulence and functional digestive symptoms

BACKGROUND

Diets rich in fermentable residues increase intestinal gas production. Our aim was to demonstrate the potential effects of diet on gas-related symptoms.

METHODS

The effect of a low-flatulogenic test diet (restricted to foodstuffs low in fermentable residues; n = 15) was compared to that of a balanced control diet (Mediterranean type; n = 15) in 30 patients complaining of flatulence and other abdominal symptoms using a randomized parallel design. The following outcomes were measured daily: number of anal gas evacuations by an event marker, severity of gas-related symptoms by 0-10 scales, and sensation of digestive comfort by a -5 (unpleasant) to +5 (pleasant) scale. Measurements were taken pretreatment for 3 days on their habitual diet and for 7 days during the treatment phase.

KEY RESULTS

No pretreatment differences were detected between patients allocated to the control or test diets. The test diet significantly reduced the number of gas evacuations (by 54 ± 10%; p = 0.002 vs basal diet) whereas the control diet had a lesser effect (reduction by 28 ± 9%; p = 0.059 vs basal diet; p = 0.089 vs test diet). Compared to the control diet, the test diet significantly reduced flatulence (by 48 ± 7% vs 27 ± 8%, respectively; p = 0.018), abdominal distension (by 48 ± 4% vs 22 ± 12%, respectively; p = 0.038), and enhanced digestive well-being (by 149 ± 18% vs 58 ± 22%, respectively; p = 0.006).

CONCLUSIONS & INFERENCES

In patients with gas-related symptoms, a low-flatulogenic diet produces immediate beneficial effects with digestive, cognitive, and emotive dimensions. The number of gas evacuations is an objective biological marker of response to dietary treatment.