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When a mobile robot moves in an unknown environment, the emergence of Simultaneous Localization and Mapping (SLAM) technology becomes crucial for accurately perceiving its surroundings and determining its position in the environment. SLAM technology successfully addresses the issues of low localization accuracy and inadequate real-time performance of traditional mobile robots. In this paper, the Robot Operating System (ROS) robot system is used as a research platform for the 2D laser SLAM problem based on the scan matching method. The study investigates the following aspects: enhancing the scan matching process of laser SLAM through the utilization of the Levenberg–Marquardt (LM) method; improving the optimization map by exploring the traditional Hector-SLAM algorithm and 2D-SDF-SLAM algorithm, and employing the Weighted Signed Distance Function (WSDF) map for map enhancement and optimization; proposing a method for enhanced relocation using the Cartographer algorithm; establishing the experimental environment and conducting experiments utilizing the ROS robot system. Comparing and analyzing the improved SLAM method with the traditional SLAM method, the experiment proves that the improved SLAM method outperforms in terms of localization and mapping accuracy. The research in this paper offers a robust solution to the challenge of localizing and mapping mobile robots in unfamiliar environments, making a significant contribution to the advancement of intelligent mobile robot technology. [ABSTRACT FROM AUTHOR]

The demand for methods that automatically create text summaries from images containing many things has recently grown. Our research introduces a fresh and creative way to achieve this. We bring together the WordNet dictionary and the YOLO model to make this happen. YOLO helps us find where the things are in the images, while WordNet provides their meanings. Our process then crafts a summary for each object found. This new technique can have a big impact on computer vision and natural language processing. It can make understanding complicated images, filled with lots of things, much simpler. To test our approach, we used 1381 pictures from the Google Image search engine. Our results showed high accuracy, with 72% for object detection. The precision was 85%, the recall was 72%, and the F1-score was 74%. [ABSTRACT FROM AUTHOR]

Selective catalytic conversion of ammonia to nitrogen is an effective method for reducing ammonia emissions from both stationary and mobile sources. In this study, CeO2-based catalysts (M/CeO2, M = Co, Cu, Fe, Zr) were synthesized using the sol–gel method and subsequently tested on a simulated gas experimental platform to assess their performance in NH3 selective catalytic oxidation (NH3-SCO). Results showed that Co/CeO2 and Cu/CeO2 catalysts exhibited high ammonia oxidation activity at respectively low temperatures, with T50 196.8 and 229.5 °C, and T90 239.2 and 292.1 °C. However, it was observed that while Co/CeO2 displayed poor N2 selectivity, Cu/CeO2 demonstrated good N2 selectivity. The superior catalytic performance of Cu/CeO2 and Co/CeO2 catalysts compared to Fe/CeO2 and Zr/CeO2 can be attributed to their distinct interactions with Ce. Subsequent characterization experiments were conducted to elucidate these interactions. BET and SEM analyses revealed that all M/CeO2 catalysts possessed a typical mesoporous structure. XRD and XPS results indicated that the primary phase of each catalyst was CeO2, and the incorporation of M transition metals did not alter the cubic fluorite structure. The interaction between the M metal and Ce varied, impacting the Ce3+ content on the catalyst surface, which in turn influenced oxygen species adsorption and ammonia oxidation activity. H2-TPR and Raman spectroscopy analyses demonstrated that M metal incorporation shifted the CeO2 reduction peak, thereby altering reduction properties and affecting oxidation performance. In particular, the Co-metal composite shifted the reduction peak to a lower temperature, thereby enhancing the reduction properties and indirectly increasing oxidation activity. [ABSTRACT FROM AUTHOR]

This study investigated the impact of diverse Pt–Pd ratios on the activity and performance of DOC. A range of Pt–Pd catalysts with different Pt–Pd ratios and monometallic Pd and Pt catalysts on Al2O3 support were evaluated systematically. 0.5%wt PGM was used to avoid the high catalyst costs. The light-off temperatures and conversion efficiencies of CO, NO, and C3H6 were investigated under simulated diesel exhaust conditions. Several scientific techniques were used to characterize the catalysts, such as XRD, XPS, H2-TPR, and CO2 TPD. The results demonstrated that using bimetallic Pt–Pd catalysts on Al2O3 support significantly improved light-off temperatures and conversion efficiency than monometallic Pt and Pd catalysts. The order of light-off temperatures and CO and C3H6 conversions was: 0.4Pt0.1Pd < 0.3Pt0.2Pd < 0.2Pt0.3Pd < 0.1Pt0.4Pd < 0.5Pd < 0.5Pt. The synergistic enhancement of catalytic activity can be ascribed to the coexistence of active sites for Pt and Pd. 0.4Pt0.1Pd bimetallic catalyst showed best activity and stability in conversion of CO and C3H6 among all catalysts. As a result of the competitive adsorption of C3H6 and CO on Pt surface, which restricts the availability of adsorbed oxygen, the monometallic Pt/Al2O3 catalyst demonstrated high light-off temperatures and slow CO and C3H6 conversion rates. However, the Pd/Al2O3 catalyst showed very stable conversion efficiency, demonstrating metallic Pd's higher stability than Pt/Al2O3. Results demonstrated that Pt can be prudently incorporated into Pd-catalysts to improve their catalytic activity. It is noteworthy that the optimal Pt to Pd ratio plays a vital role in balancing activity and stability. The careful use of Pt-modified Pt–Pd bimetallic catalysts holds promise for achieving desired emissions conversion conditions. For instance, the 0.4Pt0.1Pd bimetallic catalysts exhibited superior activity and stability in the conversion of CO and C3H6 compared to other bimetallic catalysts. Pt loading above a specific amount may reduce activity due to Pt and Pd active site overlap and saturation. [ABSTRACT FROM AUTHOR]

Depression is a multifactorial disease with unknown etiology affecting globally. It's the second most significant reason for infirmity in 2020, affecting about 50 million people worldwide, with 80% living in developing nations. Recently, a surge in depression research has been witnessed, resulting in a multitude of emerging techniques developed for prediction, evaluation, detection, classification, localization, and treatment. The main purpose of this study is to determine the volume of depression research conducted on different aspects such as genetics, proteins, hormones, oxidative stress, inflammation, mitochondrial dysfunction, and associations with other mental disorders like anxiety and stress using traditional and medical intelligence (medical with AI). In addition, it also designs a comprehensive survey on detection, treatment planning, and genetic predisposition, along with future recommendations. This work is designed through different methods, including a systematic mapping process, literature review, and network visualization. In addition, we also used VOSviewer software and some authentic databases such as Google Scholar, Scopus, PubMed, and Web of Science for data collection, analysis, and designing comprehensive picture of the study. We analyzed 60 articles related to medical intelligence, including 47 from machine learning with 513,767 subjects (mean ± SD = 10,931.212 ± 35,624.372) and 13 from deep learning with 37,917 subjects (mean ± SD = 3159.75 ± 6285.57). Additionally, we also found that stressors impact the brain's cognitive and autonomic functioning, resulting in increased production of catecholamine, decreased cholinergic and glucocorticoid activity, with increased cortisol. These factors lead to chronic inflammation and hinder the brain's normal functioning, leading to depression, anxiety, and cardiovascular disorders. In the brain, reactive oxygen species (ROS) production is increased by IL-6 stimulation and mitochondrial cytochrome c oxidase is inhibited by nitric oxide, a potent inhibitor. Proteins, lipids, oxidative phosphorylation enzymes, and mtDNA are further disposed to oxidative impairment in the mitochondria. Consequently, mitochondrial dysfunction exacerbates oxidative stress, impairs mitochondrial DNA (mtDNA) or deletions of mtDNA, increases intracellular Ca2+ levels, changes in fission/fusion and mitochondrial morphology, and lastly leads to neuronal death. This study highlights the multidisciplinary approaches to depression with different aspects using traditional and medical intelligence. It will open a new way for depression research through new emerging technologies. [ABSTRACT FROM AUTHOR]

The target of this paper is to show the impact of polarization adaptation on the received signal quality in an outdoor small-cell deployment scenario. The signal-to-interference ratio (SIR) is the key factor in defining the achievable data rate, and the capacity of the cell. At the cell border area, the SIR value is typically low and causes a significant decrease in the system capacity and achievable data rates. These bad SIR areas at the cell border can be improved by using orthogonal polarizations in the neighboring cells rather than using all polarizations over the whole cell coverage area. For the research work of this paper, a series of measurements were carried out to measure a received signal power and a cross polarization discrimination (XPD) ratio while the signal is transmitted and received with a different set of polarizations. In the measurements, we have considered horizontal, vertical, +/− 45° slanted polarizations, and two different environments, urban street and open space, and three frequency bands, 970−1030 MHz, 2000−2030 MHz and 3364−3400 MHz. The measurement results revealed that at a different distance from the transmitter, for horizontal/vertical polarization, the average XPD is around 24.7 dB and 31.7 dB in the urban street and open area environments, respectively. For +/− 45° slanted polarization, the average XPD is around 11.5 dB and 12.1 dB in the urban street and open area environments, respectively. This paper goes on to propose polarization adaptation in each cell, where the primary polarization is valid for the whole service area of the cell, and secondary polarization is only used in close proximity of the base station antenna. Considering the results, it is emphasized that system capacity can be significantly improved by having only one channel with good SIR values compared to multiple channels with bad SIR values. However, MIMO channels with orthogonal polarizations or with spatial multiplexing can be utilized in the closed vicinity of the base station, i.e., in an area with good SIR values. It is shown that the overall cell capacity can be increased by almost 35% by utilizing polarization adaptation compared to MIMO 2 × 2. [ABSTRACT FROM AUTHOR]

Understanding the genetic architecture of brain structure is challenging, partly due to difficulties in designing robust, non-biased descriptors of brain morphology. Until recently, brain measures for genome-wide association studies (GWAS) consisted of traditionally expert-defined or software-derived image-derived phenotypes (IDPs) that are often based on theoretical preconceptions or computed from limited amounts of data. Here, we present an approach to derive brain imaging phenotypes using unsupervised deep representation learning. We train a 3-D convolutional autoencoder model with reconstruction loss on 6130 UK Biobank (UKBB) participants' T1 or T2-FLAIR (T2) brain MRIs to create a 128-dimensional representation known as Unsupervised Deep learning derived Imaging Phenotypes (UDIPs). GWAS of these UDIPs in held-out UKBB subjects (n = 22,880 discovery and n = 12,359/11,265 replication cohorts for T1/T2) identified 9457 significant SNPs organized into 97 independent genetic loci of which 60 loci were replicated. Twenty-six loci were not reported in earlier T1 and T2 IDP-based UK Biobank GWAS. We developed a perturbation-based decoder interpretation approach to show that these loci are associated with UDIPs mapped to multiple relevant brain regions. Our results established unsupervised deep learning can derive robust, unbiased, heritable, and interpretable brain imaging phenotypes. A study utilizing unsupervised deep learning to generate interpretable brain imaging phenotypes from brain T1 and T2-FLAIR MRI identified 97 genetic loci enhancing understanding of brain structure genetics. [ABSTRACT FROM AUTHOR]

Connected and autonomous vehicles (CAVs) have the ability to enhance traffic flow and road safety by significantly reducing human error. Although some collision risks may be eliminated in autonomous vehicles, other potential risks remain, especially at on-ramp merging areas. This paper proposes a collision avoidance model for on-ramp merging of autonomous vehicles under different scenarios. Simulation results suggest that the proposed method can reduce the risks of collision at on-ramp merging areas. Moreover, we assessed the effectiveness of the strategy in terms of traffic flow speed variations with different penetration rates of CAVs. Results show that the collision avoidance strategy leads to lower speed variations. This study reveals that the information obtained from the proposed collision avoidance model could be helpful for improving traffic safety and enhancing urban mobility. [ABSTRACT FROM AUTHOR]

Background: Giant cell tumors (GCT) of the proximal humerus are rarely reported case that requires complex surgeries due to involvement of the shoulder joint. Therefore, we report the first retrospective comparative study where the postoperative functional outcomes, recurrence rate and complications in patients who underwent arthrodesis of shoulder after resection of grade III GCT with and without neoadjuvant denosumab are compared. Methods: A retrospective review of eight cases of grade III GCT of proximal humerus receiving resection and fibular strut graft and arthrodesis between January 2014 and December 2019 is performed. They were stratified into two groups: one group of four patients received once-weekly denosumab 120 mg for 4-weeks before resection and reconstruction, while the other group of four patients did not receive denosumab before surgery. Primary outcomes included the functional outcomes assessed by revised Musculoskeletal tumor society (MSTS) score and shoulder pain and disability index (SPDI) at 6-weeks and 12-months postoperatively while secondary outcomes included complications and recurrences. Results: There was no significant difference in terms of SPDI at 6 weeks and 12 months, MSTS at 12 months, complications, recurrence among denosumab and non-denosumab groups. At 6-weeks follow-up, a significantly better pain score in SPDI and MSTS was acquired in the denosumab group. Conclusions: Resection and reconstruction with or without neoadjuvant denosumab for Grade III GCT of proximal humerus had similar functional outcomes and with no major differences in recurrence and complications. Hence, postoperative pain relief while long-term benefits were not discovered with the use of neoadjuvant denosumab. [ABSTRACT FROM AUTHOR]

In order to perform their daily activities, a person is required to communicating with others. This can be a major obstacle for the deaf population of the world, who communicate using sign languages (SL). Pakistani Sign Language (PSL) is used by more than 250,000 deaf Pakistanis. Developing a SL recognition system would greatly facilitate these people. This study aimed to collect data of static and dynamic PSL alphabets and to develop a vision-based system for their recognition using Bag-of-Words (BoW) and Support Vector Machine (SVM) techniques. A total of 5120 images for 36 static PSL alphabet signs and 353 videos with 45,224 frames for 3 dynamic PSL alphabet signs were collected from 10 native signers of PSL. The developed system used the collected data as input, resized the data to various scales and converted the RGB images into grayscale. The resized grayscale images were segmented using Thresholding technique and features were extracted using Speeded Up Robust Feature (SURF). The obtained SURF descriptors were clustered using K-means clustering. A BoW was obtained by computing the Euclidean distance between the SURF descriptors and the clustered data. The codebooks were divided into training and testing using fivefold cross validation. The highest overall classification accuracy for static PSL signs was 97.80% at 750 × 750 image dimensions and 500 Bags. For dynamic PSL signs a 96.53% accuracy was obtained at 480 × 270 video resolution and 200 Bags. [ABSTRACT FROM AUTHOR]

The induction motor is one of the essential components of the industry. In industrial applications, the controllability, protection, and reliability of induction motors are of major concern to reserve energy. Thus, condition monitoring of an induction motor is critical for improving the unit's reliability and, as a result, reducing downtime, labor, reducing energy wastage. Induction motor stator winding and bearing failures account for 37% and 41% of failures, respectively. As the sophisticated controls rely on parameters of the motor, while the protection and reliability depend on continuous and accurate monitoring of the health of the motor. This paper covers the state of the art of parameter estimation and condition monitoring of induction motors in order to help out the industry to minimize energy wastage. In order to assist the exact operation of an induction motor, initially, the fundamentals, structure, and model of an induction motor are explained. Further, this paper covers fault diagnoses that are capable of finding the symptoms of motor failure through the state of the art of parameter estimation. In addition, the medium for the root cause of an induction motor failure is described. Finally, the paper is concluded with what has been done already, the knowledge gap, and the potential of future research. [ABSTRACT FROM AUTHOR]

Purpose: To describe the design, implementation, and adoption of a simplified electronic medical record (EMR) and its use in documenting pediatric central nervous system (CNS) tumors at a tertiary care referral hospital in South-East Asia. Methods: A novel EMR, cataloguing pediatric CNS tumors was used to collect data from August 2017 to March 2020 at National Institute of Neurosciences and Hospital (NINS&H) in Dhaka, Bangladesh. Results: Two hundred forty-nine pediatric patients with a CNS tumor were admitted to NINS&H. Fifty-eight percent of patients were male, and the median age was 8 years. A total of 188/249 patients (76%) underwent surgery during their index admission. Radiographic locations were known for 212/249 (85%) of cases; the most common radiographic locations were infratentorial (81/212; 38%), suprasellar (45/212; 21%), and supratentorial (29/212; 14%). A histopathological classification was reported on 156/249 (63%) of patients' cytology. The most common infratentorial pathologies were medulloblastoma (22/47; 47%) and pilocytic astrocytoma (14/47; 30%). The median time between admission and surgery was 36 days, while the median post-operation stay was 19.5 days. Conclusions: The feasibility of a basic EMR platform for a busy pediatric neurosurgery department in a lower-middle income country is demonstrated, and preliminary clinical data is reviewed. A wide variety of pediatric CNS tumors were observed, spanning the spectrum of anatomic locations and histopathologic subtypes. Surgical intervention was performed for the majority of patients. Barriers to care include limited molecular diagnostics and unavailable data on adjuvant therapy. Future targets include improvement of clinical documentation in the pre-operative and post-operative period. [ABSTRACT FROM AUTHOR]

The frequency spectrum is a scarce resource, and is owned and regulated by the state to ensure its efficient and fair utilization. All over the world, a large number of Mobile Network Operators (MNOs) are already involved in either active or passive Radio Access Network (RAN) sharing to maximize cost savings. The aim of this article is to challenge the ownership of individual operator's infrastructure and present technical arguments for One Radio Access Network (OneRAN) approach for deploying a cellular network. The enormous increase in data traffic and regulatory requirements concerning public safety communications provide the basis for migrating to OneRAN infrastructure. The OneRAN approach provides an opportunity to gain technological benefits and helps in meeting the requirements of critical communication. OneRAN targets to maximize the savings on capital and operational expenses. The main focus of this work is outdoor wide-area coverage i.e., outdoor users in rural areas and on highways, as it is assumed that indoor service provision in the future requires a dedicated indoor solution. For the research work of this article, a measurement campaign was launched and different Key Performance Indicators(KPIs) of Long Term Evolution(LTE) technology for three commercial MNOs of Finland were measured over a 52 km highway from Iittala to Tampere city. The acquired results highlight the gain of OneRAN infrastructure as it enhanced the user quality of experience i.e., user throughput, especially of the critical cell border users, and improved the overall system performance economically. Finally, supportive arguments are presented for having a OneRAN infrastructure specifically over the highways. [ABSTRACT FROM AUTHOR]

Background: Denosumab has been approved by Food and Drug Authority in 2013 for use in surgically unresectable Giant cell tumor (GCT) to achieve resectable tumor margins. The aim of this study is to investigate the functional outcome and surgical convenience with the use of neoadjuvant denosumab before resection and reconstruction in Campanacci grade III GCT. Methods: We retrospectively reviewed 70 cases of Campanacci grade III GCT receiving resection and reconstruction between January 2014 and December 2019. They were stratified into two groups: one group of 29 patients received once-weekly denosumab 120 mg for 4-weeks before resection and reconstruction, while the other group of 41 patients did not receive denosumab before resection and reconstruction. Quality of life by musculoskeletal tumor society score where 0–7 means poor, 8–14 means fair, 15–22 means good; above 22 means excellent, incidence of tumor recurrence, intraoperative duration in minutes and postoperative positive margins were assessed for each cohort after 12 months follow-up. Results: There was no significant difference in musculoskeletal tumor society score (25.75 vs. 27.41; P = 0.178), incidence of recurrence (3.45% vs. 4.88%; P < 0.001), and postoperative positive margins (10.34% vs. 4.88%; P = 0.38) for both groups. However, the intraoperative duration (133.38 vs. 194.49; P < 0.001) was significantly higher in the non-denosumab group compared with denosumab group. Conclusions: Neoadjuvant denosumab is equally effective considering postoperative functional outcomes and surgical convenience except intraoperative duration where it is highly helpful in saving the operating time duration. Easier identification, resection and lesser reconstruction are the key surgical convenience offered by neoadjuvant denosumab. [ABSTRACT FROM AUTHOR]

The influence of unit cell configuration and relative density on compression behavior, deformation mechanism and energy absorption capacity of body centered cubic (BCC) flexible polymeric lattice structures was experimentally investigated in this work. Three different types of BCC cell configurations i.e. uniform cell (UBCC), uniform with z-axis reinforced cell (UBCCz) and graded cell (GBCC) were additively manufactured through digital light processing 3D printing process. Quasi static compressive testing was carried out to determine the mechanical response of lattice structures and significant effect of cell architecture and relative density on compression and strength properties were observed. The experimental results show that irrespective of lattice type the elastic modulus and collapse strength of each lattice increases with increasing relative density. However, the modulus and strength for UBCCz is higher than other two configurations due to additional vertical strut which add extra stiffening in loading direction. UBCCz lattice also showed high energy absorption capacity followed by UBCC and GBCC lattice. It was also determined that for any fixed relative density, different lattice configurations show different stress-strain behavior and deformation modes due to unique unit cell construction. The non-graded lattice shows a uniform overall deformation while gradient lattice shows layer by layer collapse. The work proposed that lattice relative density and cell configuration can be steered to improve the overall stiffness and strength of flexible lattice structures in energy absorption applications. [ABSTRACT FROM AUTHOR]

Natural fibers, especially jute fibers, have gained interest in recent decades due to their attractive mechanical properties, high cellulose percentage, low cost, biodegradability, and easy availability. In the present study, flexural and drop weight impact behavior for different weight percentages of glass and jute fiber reinforced epoxy composites are studied experimentally according to ASTM standards. The hybrid composites were prepared through the compression molding technique. Numerical simulations were performed to investigate the predictive flexural response. The leading cause of error between experimental and numerical results is the manufacturing process and the reinforcement's woven nature. On the other hand, the impact strength was studied through drop weight testing at fixed 10 J energy. It is found that damage area decreases with increasing jute percentage in glass/jute hybrid composites, showing that jute fiber contributes more towards the composites' impact strength than glass fiber. Therefore, jute fiber can replace glass fiber in the glass/jute hybrid composite as a natural and eco-friendly constituent. The microscopic study reveals that the outer glass fiber layer helps minimize the stress distribution of jute fiber. A significant drawback of compression molding is the epoxy affluent areas in the composite. [ABSTRACT FROM AUTHOR]

The aim of this work is to study the impact of small receiver displacement on a signal propagation in a typical conference room environment at a millimeter wave frequency of 60 GHz. While channel measurements provide insights on the propagation phenomena, their use for the wireless system performance evaluation is challenging. Whereas, carefully executed three-dimensional ray tracing (RT) simulations represent a more flexible option. Nevertheless, a careful validation of simulation methodology is needed. The first target of this article is to highlight the benefits of an in-house built three-dimensional RT tool at 60 GHz and shows the effectiveness of simulations in predicting different characteristics of the channel. To validate the simulation results against the measurements, two different transmitter (Tx) positions and antenna types along with ten receiver (Rx) positions are considered in a typical conference room. In first system configuration, an omnidirectional antenna is placed in the middle of the table, while in the second system configuration a directed horn antenna is located in the corner of the meeting room. After validating the simulation results with the measurement data, in the second part of this work, the impact of a small change, i.e., 20 cm in the receiver position, is studied. To characterize the impact, we apply as performance indicators the received power level, root mean square delay spread (RMS-DS) and RMS angular spread (RMS-AS) in azimuth plane. The channel characteristics are considered with respect to the direct orientation (DO), i.e., the Rx antenna is directed toward the strongest incoming path. Different antenna configurations at the Tx and Rx side are applied to highlight the role of antenna properties on the considered channel characteristics. Especially, in the second system configuration the impact of different antenna half power beamwidth on different considered channel characteristics is highlighted through acquired simulation results. The validation of results shows the RMS error of only 2–3 dB between the measured and simulated received power levels for different Tx configurations in the direction of DO. Results indicate that only a small change of the Rx position may result a large difference in the received power level even in the presence of line-of-sight between the Tx and Rx. It is found that the STD of received power level across the room increases with the decrease in HPBW of the antenna. As can be expected, directed antennas offer lower value of RMS-DS and RMS-AS compared with isotropic antenna. [ABSTRACT FROM AUTHOR]

The phytotoxic effects of two allelochemicals (trans-cinnamic acid and syringaldehyde) at different concentrations (1000, 100, 10, and 1 µM) on seed germination, seedling growth, and physiological and biochemical changes of Echinochloa crus-galli L. were tested by comparison to a commercial herbicide 'Nominee' (that is, 100 g/L bispyribac-sodium). trans-Cinnamic acid and the herbicide inhibited seed germination completely at 100 µM, whereas for syringaldehyde, complete inhibition required 1000 µM. However, with 100 µM syringaldehyde, the seed germination of the test species was 53% of the control. Allelochemicals and the herbicide delayed seed germination and significantly affected the speed of germination index (S), speed of cumulative germination index (AS), and coefficient of germination rate (CRG). The roots were more affected when nutrients were not added to the growth bioassay. In general, with the increasing concentration of allelochemicals from 100 to 1000 µM, the inhibitory effects increased. Via microscopy analysis, we found leaf blade wilting and necrosis at concentrations above 100 µM in allelochemical-treated plants. Roots of E. crus-galli treated with 1000 µM allelochemicals had black points on root nodes but had no root hairs. The anatomy of roots treated with allelochemicals (1000 µM) showed contraction or reduction of root pith cells as well as fewer and larger vacuoles compared to the control. The allelochemicals also showed remarkable effects on seedling growth, SPAD index, chlorophyll content, and free proline content in a pot culture bioassay, indicating that trans-cinnamic acid and syringaldehyde are potent inhibitors of E. crus-galli growth and can be developed as herbicides for future weed management strategies. [ABSTRACT FROM AUTHOR]

In this paper, an unsupervised automatic method based on a current signature neural network (NN) is presented to on-line diagnose stator fault without the inspection of any supervisor or technician. To extract the fault regime, the knowledge of current signature will not be enough; therefore, mathematical model, numerical analysis, as well as artificial intelligence (AI) are taken into account to extract the exact unbalanced voltage stator fault. Analytical expressions are derived for a stator conductor segment in order to find out the conductors that are responsible for the generation of magnetomotive force (MMF). A test rig is designed using three-phase induction motor, two-axis PASPORT sensor, PC, and PASCO interface to compute the effect of MMF at the stator side through a new series of harmonics which are helpful to tackle the scrupulous effect of an unbalanced voltage at the incipient stage. Further, an unsupervised NN has been introduced that endeavors the principal components of the new series of harmonics. The statistical parameters of a new series of harmonics are contemplated as input features for NN that not only diagnose unbalanced voltage but also identify the degree of unbalanced voltage through feed-forward multilayer perceptron (MLP) trained by backpropagation. The validation and performance of proposed methods have been theoretically and experimentally analyzed on a custom-designed test rig under various levels of unbalanced voltage. Moreover, the NN classification method shows higher accuracy with enough robustness to various levels of unbalanced voltage, which states that the proposed method is suitable for the real-world applications. [ABSTRACT FROM AUTHOR]

Metallic materials are mostly rate dependent in mechanical behavior, but their elastic modulus under high strain rate is hard to measure accurately. In this paper, two methodologies are proposed based on stress wave theory in hope of accurate measurement for metallic materials, for example Ti6Al4V alloy. One is based on the one-dimension stress wave propagation in a long Ti6Al4V bar, and the elastic modulus under a high strain rate is obtained from the calculated stress wave speed. The other technique is to utilize the integrated Hopkinson pressure bar made of Ti6Al4V material. The obtained elastic moduli from these methods are compared and analyzed, and the results are consistent with each other. The numerical simulations with cylindrical and dogbone-shaped specimens are conducted to show the influence of bar indentation on measurement accuracy. An alternative method is introduced based on the vertical split Hopkinson pressure bar, which can extend the integrated Hopkinson pressure bar method for most metallic materials with small bulk. The verification experiments are also conducted. Finally, the limiting strain rate is estimated for potential measurement problems. [ABSTRACT FROM AUTHOR]

Induction motors are the workhorse component of many industries and are frequently integrated into equipment. Many industries faced one of the serious problems regarding its maintenance issues. According to Neale and Wowk, the maintenance expenditure can be up to 80% of the total cost of motor. According to the reliable study by Electric Power Research Institute, the inter-turn short-circuit faults approximately contribute 37% of the induction motor failures. In the literature, most of the techniques are reviewed that are used to diagnose the fault in stator winding and it is found that majority of motor failures are due to insulation breakdown. It is found the unbalanced voltage is one of the major sources of insulation failure. And most of the exiting techniques to diagnose this fault are off-line or sensor bases. In this work, noninvasive online method is proposed; first of all, an analytical expression is derived for the conductor segments in the stator winding that are responsible for the generation of magnetomotive force (MMF). Therefore, stator windings are partitioned down into two set of segments (slot conductors and end conductors). The slot conductors are of major interest because their axial arrangement in the slots provides a room to establish MMF in order to generate a torque. Further, in this paper, an expression for MMF is derived through winding function approach. It was found that besides the fundamental MMF, there exist waves with a different number of poles. This MMF will induce a voltage in a stator winding through rotor side. In addition, the effect of MMF is considered on the current spectrum of induction motor because the knowledge of current spectrum under faulty regimes is the point of interest to diagnose a motor fault in a noninvasive way. Moreover, a new series of rotor harmonic frequency component are introduced to diagnose unbalanced voltage supply. Finally, the proposed analytical models and new series of rotor harmonic sheds a light on stator current components to diagnose and distinguish between balanced and unbalanced voltage supply in a real-time scenario. To validate the proposed method, two experimental hardware setups were designed comprising of a three-phase induction motor, two-axis magnetic field sensor, 8821-2A variable power source, current transformer, FLUKE 435 II series power quality energy analyzer, and Pasco interface for data acquisition. The appearance and significant increase in the magnitude of a new series of harmonics under unbalanced voltage are the indication of unbalanced voltage supply. Thus, the experimental data clearly justify and validate the proposed analytical model with the results of hardware setup. [ABSTRACT FROM AUTHOR]

The target of this article is to analyze the impact of transition from cellular frequency band i.e. 2.1 GHz to Millimeter Wave (mmWave) frequency band i.e. 28 GHz. A three dimensional ray tracing tool “sAGA” was used to evaluate the performance of the macro cellular network in urban/dense-urban area of the Helsinki city. A detailed analysis of user experience in terms of signal strength and signal quality for outdoor and indoor users is presented. Indoor users at different floors are separately studied in this paper. It is found that in spite of considering high system gain at 28 GHz the mean received signal power is reduced by almost 16.5 dB compared with transmission at 2.1 GHz. However, the SINR is marginally changed at higher frequency. Even with 200 MHz system bandwidth at 28 GHz, no substantial change is witnessed in signal quality for the outdoor and upper floor indoor users. However, the users at lower floors show some sign of degradation in received signal quality with 200 MHz bandwidth. Moreover, it is also emphasized that mobile operators should take benefit of un-utilized spectrum in the mmWave bands. In short, this paper highlights the potential and the gain of mmWave communications. [ABSTRACT FROM AUTHOR]

The target of this paper is to analyze the impact of variation in antenna radiation pattern on the performance of Single Path Multiple Access (SPMA) in urban/dense-urban environment. For this study, an extended 3GPP antenna model, and 3D building data from an urban area of Helsinki city is used. The simulations are performed at 28 GHz frequency using “sAGA” a MATLAB based 3D ray tracing tool. The variables considered for the series of simulations are Front to Back Ratio (FBR), Side Lobe Level (SLL), and Half Power Beamwidth (HPBW) of an antenna in horizontal and vertical plane. Network performance is compared in terms of metrics like signal strength, SINR, and capacity. This paper also presents the spectral efficiency and power efficiency analysis. The performance of SPMA was found susceptible to the change in antenna radiation pattern, and the simulation results show a significant impact of radiation pattern on the capacity gain offered by SPMA. Interestingly, SPMA was found a fairly power efficient solution with respect to the traditional macro cellular network approach. However, the level of power efficiency heavily depends upon the antenna beamwidth and on other beam parameters. [ABSTRACT FROM AUTHOR]

The evolution of mobile networks has been extremely fast during the last decade. However, the advancements in the technological ways of improving the system capacity are not enough for the data revolution we have witnessed in the last couple of years, and for the data traffic forecast made by the professionals for the next decade. Several recent technological enhancements may double the network capacity, or may even increase the system capacity 5-10 times, but still it is far away from the expected 'need for a thousandfold more capacity'. The fifth Generation (5G) of mobile networks with a slogan of thousandfold more capacity has compelled the research community to think in an 'Innovative Way' and to think 'Outside the box'. The aim of this article is first to show the limitations of recent technology solutions for the future demands, and thus to highlight the need for more innovative breakthrough solutions. The excellence of centralized macro sites is argued as a principal capacity layer instead of micro cells, small cells, or femto cells. Moreover, it is also argued that an ultimate need for innovative antenna solutions for macro sites is required instead of traditional antenna array technologies. [ABSTRACT FROM AUTHOR]

The next generation of cellular networks is expected to provide huge capacity, and site densification is one of the possible solution to increase the network capacity. The target of this paper is to show the impact of macro/micro site densification and higher order sectorization on signal strength, signal quality and throughput in LTE network. It also highlights the impact of site and sector densification on the cell overlapping and cell border areas. A detailed techno-economical analysis along with area power consumption and area spectral efficiency is also provided in this paper. In site densification, the intersite distance (ISD) between the base station sites is decreased, which results in strong inter cell interference. The results presented in this paper show that the spectral efficiency of the cell decreases with the site densification. However, the average area spectral efficiency increases due to a larger number of cells in the densified network. At the same time the number of cell border users overlapped by multiple servers also increases with the site and sector densification. It is shown that in one square kilometer, increasing the number of cells from 14 (3-sector site with 500 m ISD) to 693 (6-sector site with 100 m ISD) relatively improves the area spectral efficiency by 24.5 times at the cost of 49.5 times more number of cells. Almost identical power efficiency is provided with 3-, and 6-sector site. However, a higher order sectored site was found to be more cost efficient. [ABSTRACT FROM AUTHOR]

We study the effect of mood-proxy variables on index returns and volatility in six South Asian markets. Our mood-proxy variables include six weather (temperature, humidity, cloud cover, air pressure, visibility, and wind speed), three weather indicator variables (fog, thunder storm and rain or drizzle) and two biorhythmic variables (SAD and lunar phases). We adopt a robust approach and attempt to select the best parsimonious econometric model for each market. Our findings suggest that mood-proxy variables have some convincing influences in South Asian capital markets. In some instances, these variables are influencing returns while in other instances they are influencing volatility. [ABSTRACT FROM AUTHOR]

The scheduling algorithm is a fundamental design problem to allocate resources amongst different entities in distributive wireless sensor networks (WSNs). These sensor nodes have limited power and non-replenishable energy resources. In WSNs, the duty cycling mechanism is commonly used to save energy due to idle listening. On the other hand, a fixed duty cycling mechanism increases transmission latency in WSNs. Therefore, in order to ensure the prolonged network-life of WSNs, the medium access control (MAC) protocol should be tackled in an efficient manner to improve energy efficiency by minimizing idle listening, maximizing sleep duration, and eliminating data collision. This paper proposes a practical Adaptive Sleep Efficient Hybrid Medium Access Control (AEH-MAC) algorithm in which the key idea is to dynamically adjust nodes' sleep time to improve the scheduling in WSNs. The AEH-MAC allows nodes to adjust sleep time dynamically according to the traffic load and coordinate wakeup time with neighbour nodes. A series of short taken packets are transmitted to wake the receiver, and a prediction field is introduced in the ACK packets (GRANT/RELEASE) to reduce the waiting time of the source node. In the proposed algorithm, each node maps a conflict-free time slot for itself up to two-hop neighbouring nodes. The simulation results show that the AEH-MAC algorithm achieves high performance in terms of runtime, number of rounds, energy consumption, and slot reservation. [ABSTRACT FROM AUTHOR]

This paper highlights the performance of single path multiple access (SPMA) and discusses the performance comparison between higher order sectorization and SPMA in a macrocellular environment. The target of this paper is to emphasize the gains and significance of the novel concept of SPMA in achieving better and homogeneous SIR and enhanced system capacity in a macrocellular environment. This paper also explains the algorithm of SIR computation in SPMA. The results presented in this paper are based on sophisticated 3D ray tracing simulations performed with real world 3D building data and site locations from Seoul, South Korea. Macrocellular environment dominated with indoor users was considered for the research purpose of this paper. It is found that by increasing the order of sectorization, SIR along with spectral efficiency degrades due to the increase in inter-cell interference. However, as a result of better area spectral efficiency due to increased number of sectors (cells), the higher order sectorization offers more system capacity compared to the traditional 3-sector site. Furthermore, SPMA shows an outstanding performance and significantly improves the SIR for the individual user over the whole coverage area, and also remarkably increases the system capacity. In the environment under consideration, the simulation results reveal that SPMA can offer approximately 424 times more system capacity compared to the reference case of 3-sector site. [ABSTRACT FROM AUTHOR]

The aim of this paper is to introduce a novel frequency reuse concept especially for macro cellular networks to substantially increase the mobile network capacity, and simultaneously to avoid the implementation of low efficient small cells. Single path multiple access (SPMA) utilizes the characteristics of independent propagation paths for particular geographical location in the coverage area of mobile network. The proposed concept is based on the assumption that new approach will be adopted by the antenna manufacturers for producing advanced antennas by utilizing materials like metamaterials including carbon based nanotechnology, and graphene. In SPMA concept, communication between base station and mobile station happens through only single independent propagation path, and frequency resources can be reused in 5 m $$\times $$ 5 m areas or even more often in 1 m $$\times $$ 1 m areas, but limited by a base station/mobile station antenna requirement. Thus, the capacity of the network will be increased dramatically, and it can be managed in centralized manner at certain macro site locations. In already deployed cellular networks, these macro sites are mostly easily available, and that would help to implement SPMA to enhance the network capacity. Simulation results provided in this paper show the applicability of SPMA technique, by limiting the radiation of signal as single path propagation between base station and mobile station. [ABSTRACT FROM AUTHOR]

Chronic hepatitis B virus (HBV) infection may result in cirrhosis and/or hepatocellular carcinoma and is one of the leading causes of mortality in Asian Americans including Hmong Americans. The Central California Valley is home to a huge Hmong population. To date, the true prevalence of HBV among Hmong is largely unknown. The aim of this study was to contribute to the limited data on HBV prevalence and its trends in Hmong population in the Central California Valley. Between fiscal years 2006 and 2010, a total of 219, 450 voluntary donors were identified at Central California Blood Center in Fresno. Of these, 821 (399 males and 422 females) were Hmong donors. A cross-sectional review of the HBV (hepatitis B surface antigen) positivity among all donors was carried out. Prevalence estimates with 95% confidence intervals (CI) were calculated. Ninety-two percent of Hmong donors were between age groups 16 and 35 years, and only 8% were ≥36 years. The overall prevalence in Hmong was noted at 3.41% (95%CI 2.3-4.9) compared to 0.06% (95%CI 0.05-0.07) in donors of all ethnicities. The calculated prevalence could be an underestimate of the true HBV prevalence in Hmong as the study enrolled only healthy blood donors with predominant younger age (≤35 years) population. These results underscore the persistent burden of HBV infection and potentially increased risk of premature death even in the second generation Hmong community of the Central California Valley. This study reemphasizes the unequivocal need to develop robust preventive and treatment strategies for HBV in Hmong community. [ABSTRACT FROM AUTHOR]

Chronic hepatitis B infection (HBV) is the major cause of primary liver cancer worldwide and Asians are disproportionately affected. The prevalence of HBV among most Asian American groups has been well documented, except in Hmong immigrants in the United States. The aim of this study was to determine the prevalence of HBV among Hmong immigrants in the San Joaquin Valley of California. A convenient sample of 534 Hmong age ≥18 years was recruited at various locations throughout Fresno County. Blood samples from study participants were collected and tested for hepatitis B surface antigen (HBsAg) by enzyme-immunoassay. Two hundred and eighty-nine females and 245 males of Hmong descent (mean age, 43.93) were screened. Eighty-nine (41 males and 48 females) were positive for HBsAg, which accounts for a prevalence of 16.7% (95% C.I. 13.5-19.9). The majorities of HBsAg positive patients were ≥40 years (64.2%), married (66.7%), born in Laos (87.3%), and had lived in the United States ≥20 years (62.5%). Only 37.5% of the participants reported having a primary care physician. Our study revealed that approximately one out of every six Hmong immigrants screened was infected with HBV. Based on our findings, more than one-third of these infected patients have no primary care physician to provide further treatment, surveillance for liver cancer, or vaccination of their families. This supports the Institute of Medicine's recent recommendations to the Center for Disease Control to engage in a national Hepatitis B surveillance system. [ABSTRACT FROM AUTHOR]

Bacterial infections are common in cirrhosis and can lead to life-threatening complications. Sidestream dark-field (SDF) imaging has recently emerged as a noninvasive tool for capturing real-time video images of sublingual microcirculation in critically ill patients with sepsis. The objective of this study was to assess the utility of SDF in determining underlying infection in patients with cirrhosis. Sublingual microcirculation was compared among patients with compensated cirrhosis (Group A, n=13), cirrhosis without sepsis (Group B, n=18), cirrhosis with sepsis (Group C, n=14), and sepsis only (Group D, n=10). The blood flow was semi-quantitatively evaluated in four equal quadrants in small (10-25 mm); medium (26-50 mm); and large (51-100 mm) sublingual capillaries. The blood flow was described as no flow (0), intermittent flow (1), sluggish flow (2), and continuous flow (3). The overall flow score or microvascular flow index (MFI) was measured for quantitative assessment of microcirculation and predicting power for concurrent infection in cirrhosis. Marked impairment was observed at all levels of microvasculature in Groups B and C when compared with Group A. This effect was restricted to small vessels only when Group B was compared with Group C. MFI<1.5 was found to have highest sensitivity (100%) and specificity (100%) for infection in decompensated cirrhosis. SDF imaging of sublingual microcirculation can be a useful bedside diagnostic tool to assess bacterial infection in cirrhosis. [ABSTRACT FROM AUTHOR]

Climate change caused by anthropogenic activities has generated a variety of research focusing on investigating the past climate, predicting the future climate and quantifying the change in climate extreme events by using different climate models. Climate extreme events are valuable to evaluate the potential impact of climate change on human activities, agriculture and economy and are also useful to monitor the climate change on global scale. Here, a Regional Climate Model (RCM) simulation is used to study the future variations in the temperature extreme indices, particularly change in frequency of warm and cold spells duration over Pakistan. The analyses are done on the basis of simulating two 30 years simulations with the Hadley Center’s RCM PRECIS, at a horizontal resolution of 50 km. Simulation for the period 1961–1990 represents the recent climate and simulation for the period 2071–2100 represents the future climate. These simulations are driven by lateral boundary conditions from HadAM3P GCM of Hadley centre UK. For the validation of model, observed mean, maximum and minimum temperatures for the period 1961–1990 at all the available stations in Pakistan are first averaged and are then compared with the PRECIS averaged grid-box data. Also the observed monthly gridded data set of Climate Research Unit (UK) data is used to validate the model. Temperature indices in the base period as well as in future are then calculated and the corresponding change is observed. Percentile based spatial change of temperature shows that in summer, increase in daily minimum temperature is more as compared to the increase of daily maximum temperature whereas in winter, the change in maximum temperature is high. The occurrence of annual cold spells shows significantly decreasing trend while for warm spells there is slight increasing trend over Pakistan. [ABSTRACT FROM AUTHOR]

Hepatic steatosis is a frequent histologic finding in chronic hepatitis C (CHC) patients. Both host and viral factors contribute to steatogenesis. Recent literature has demonstrated the interaction of viral proteins with hepatic cellular components, resulting in oxidative stress, cytokine release, inflammation, insulin resistance, and disturbance in lipid and carbohydrate metabolism. These viral-induced hepatocellular abnormalities thus initiate development of steatosis, worsening fibrosis, poor therapeutic response, and carcinogenesis. Steatosis in hepatitis C appears to be genotype specific and is predominantly metabolic in genotype 1 and cytopathic in genotype 3. This review discusses the details of complex pathogenic mechanisms of steatosis in CHC patients. The impact of steatosis on the disease’s natural history is discussed, and future directions are outlined. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The clinical significance of portal hypertensive gastropathy (PHG) in patients with compensated liver disease is not well established. The aim of this study was to determine the prevalence and correlates of PHG in a large cohort of patients with chronic hepatitis C virus (HCV) infection and bridging fibrosis/compensated cirrhosis entering the randomized phase of the Hepatitis C Antiviral Long-term Treatment against Cirrhosis trial (HALT-C). METHODS: The presence and severity of PHG in 1,016 HCV patients with no prior history of gastrointestinal bleeding was determined at surveillance endoscopy using the New Italian Endoscopy Club criteria. RESULTS: Overall, 37% of HALT-C patients had PHG with 34% having mild and 3% with severe changes. The mucosal mosaic pattern was identified in 33%, red marks in 15%, and gastric antral vascular ectasia (GAVE) features in only 3%. Independent correlates of PHG included biochemical markers of liver disease severity (lower serum albumin, higher bilirubin), portal hypertension (lower platelet count), insulin resistance (higher glucose), and non-African American race. Independent correlates of GAVE included a history of smoking, nonsteroidal anti-inflammatory drugs (NSAIDs) use within the past year, and higher serum bilirubin and glucose levels. There was a strong positive association between the presence of PHG and esophageal varices ( p < 0.0001). CONCLUSIONS: PHG is associated with the histological and biochemical severity of liver disease in patients with HCV and advanced fibrosis but is mild in most patients. The clinical relevance of these findings will be further explored during the randomized phase of the HALT-C study. [ABSTRACT FROM AUTHOR]

The quantitative liver-spleen scan (QLSS) can estimate the functional hepatic mass and the organ volumes by precise measurement of sulfur colloid (SC) distribution. The normal range determined in prior studies was estimated from patients with absence of chronic liver disease in which intense fasting appeared to produce slightly abnormal values. This study was to determine the effect of fasting or fed status and colloid particle size on quantitative measurements from the QLSS in a small cohort of normal individuals. Twelve persons without any medical problems had QLSS taken twice, 2 weeks apart, one fasting and one postprandial. Patients were scanned after injection of 5-6 mCi of SC; six patients were given solution A (5- to 12-microm particle size) and six patients solution B (2- to 12-microm particle size). SPECT and planar analysis were performed. SC distribution of total counts between the liver and the spleen {[L/(L + S)]t ratio}, liver-spleen index (LSI), and liver-bone marrow index (LBI) were calculated. The perfused hepatic mass (PHM) is the average of the LSI and LBI. Spleen and liver volumes are expressed as milliliters per pound ideal body weight (IBW). Results showed that the liver and spleen volumes (solution B postprandial, 9.27 +/- 2.48 and 1.47 +/- 0.57 ml/lb IBW, respectively) and LBI were not affected by the type of SC solution or by ingestion status. L/(L + S) total and pixel count ratios were significantly higher for solution B and postprandial studies. [L/(L + S)]t, LSI, and PHM increased significantly (P < 0.05) from fasting to postprandial for solution A (0.71 +/- 0.13 vs 0.79 +/- 0.08, 80 +/- 14 vs 91 +/- 8, and 102 +/- 10 vs 106 +/- 8, respectively) and for solution B (0.81 +/- 0.05 vs 0.90 +/- 0.02, 86 +/- 4 vs 95 +/- 3, and 101 +/- 5 vs 110 +/- 3). Neither fasting nor postprandial LSI and PHM were significantly different between solution A and solution B. We conclude the following. (1) The QLSS functional indices in "true" normal patients fall within the previously reported normal range. (2) Calculated liver and spleen volumes are not altered by fasting or sulfur colloid particle size. (3) Fasting significantly decreased the [L/(L + S)]t, LSI, and PHM. (4) A postprandial scan may be preferable since the normal values for [L/(L + S)]t, LSI, and PHM are greater, with a narrower range, than fasting values. [ABSTRACT FROM AUTHOR]

Selective intestinal decontamination withnorfloxacin is useful in preventing spontaneousbacterial peritonitis in cirrhotic patients and also incirrhotic rats. The emergence of norfloxacin-resistantinfections in these patients warrants a search foralternative therapies. The aim of this study was toevaluate the effect of long-termtrimethoprimsulfamethoxazole administration on carbontetrachloride (CCl4)-induced cirrhosis inrats with specific attention to intestinal flora,bacterial translocation, spontaneous bacterialperitonitis (SBP), and survival. Male Sprague-Dawleyrats received CCl4 administered weekly bygavage. After eight weeks of CCl4administration rats were randomly allocated into twogroups. Group I received daily overnighttrimethoprim-sulfamethoxazole diluted in phenobarbital water during follow-up and groupII did not. The rats were killed when gravely ill, anda laparotomy was performed to culture samples of cecalstool, mesenteric lymph nodes, and portal and inferior vena caval blood. There was a trendtoward a reduction in the incidence of bacterialtranslocation (8/17 vs 11/14, respectively) and SBP(5/17 vs 7/14, respectively) in treated rats that werekilled just before death compared to untreated rats.A decrease in the incidence of bacterial translocationcaused by gramnegative bacilli was observed in group I(17.6% vs 78.6% , P < 0.01). The development of ascites was delayed in group I (P < 0.05)and survival was prolonged in group I (P < 0.05),despite a higher CCl4 dose in this group (P< 0.05). In conclusion, long-term prophylactic trimethoprim-sulfamethoxazole administration inCCl4-induced cirrhosis in rats delayed thedevelopment of ascites, prolonged survival, and reducedthe incidence of gramnegative bacterial translocation but not of SBP, without increasinggram-positive episodes. These data suggest thattrimethoprim-sulfamethoxazole might be a goodalternative to norfloxacin for preventing gram-negativebacterial translocation. [ABSTRACT FROM AUTHOR]