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Background: Rickettsial infections are often neglected and poorly recognized by physicians in many tropical and subtropical regions. Despite a number of recent reports describing rickettsial diseases in new locations and the discovery of new rickettsiae, medical science and research have largely neglected the diagnosis and antimicrobial treatment of rickettsial infections in subtropical and tropical areas; thus, much remains to be discovered. This study aimed to detect and characterize spotted fever group (SFG) rickettsiae in ixodid ticks infesting domestic ruminants in Khartoum State. Methods: Polymerase chain reaction targeting both genes that encode for citrate synthase (gltA) and outer membrane protein (ompA) was performed for the presence of SFG rickettsia followed by sequence and phylogenetic analysis. Results: Of the 202 ticks examined for the presence of SFG rickettsia, gltA gene was detected in 4 samples (2%). Furthermore, gltA‐positive samples were used to amplify the ompA gene, in which only two samples yielded positive results. Sequence and phylogenetic analysis of the positive samples revealed four different species of SFG rickettsiae: Rickettsia aeschlimannii, Rickettsia rhipicephali, Rickettsia massiliae and Rickettsia raoultii. Conclusions: These results indicated the presence of SFG rickettsia in Sudanese ticks. This also indicates that humans have an opportunity to acquire these infections. It is important to keep in mind the need for careful consideration of rickettsial infections in individuals with a fever of unknown origin. [ABSTRACT FROM AUTHOR]

Background: The proadaptive effects of glucagon‐like peptide‐2 (GLP‐2) include stimulation of intestinal mucosal growth as well as intestinal blood flow and angiogenesis. We have recently reported that daily subcutaneous injections of glepaglutide, a long‐acting GLP‐2 analog, improved intestinal absorptive function in patients with short bowel syndrome (SBS). As secondary and exploratory end points, the effects of glepaglutide on intestinal morphology and perfusion are reported. Methods: The following assessments were done in 18 patients with SBS in a randomized, crossover, dose‐finding, phase 2 trial before and after three weeks of treatment with glepaglutide: plasma citrulline and mucosa biopsies to assess changes in (1) intestinal morphology by immunohistochemistry and (2) gene expressions associated with absorption, proliferation, and markers of tight‐junction integrity by quantitative polymerase chain reaction. Intestinal perfusion was assessed in stoma nipples by laser speckle contrast imaging and quantitative fluorescence angiography with indocyanine green. Results: In the 1‐ and 10‐mg dose groups, glepaglutide significantly increased plasma citrulline by 15.3 µmol/L (P = 0.001) and 15.6 µmol/L (P = 0.001), respectively. Trends toward an increase in villus height, crypt depth, and epithelium height were seen in the same groups. No significant changes were seen in gene expressions or intestinal perfusion. Conclusion: The increase in plasma citrulline and the morphological improvements may partly account for improvement in the intestinal absorptive function. However, the finding of a stability in perfusion after three weeks of treatment with glepaglutide may have been preceded by a more profound acute‐phase increase in intestinal perfusion at treatment initiation. [ABSTRACT FROM AUTHOR]

Background: Toxoplasma gondii (T. gondii) is a zoonotic parasite that can be transmitted from animals to humans, with felids acting as its definitive host. Thus, understanding the epidemiology of this parasite in animal populations is vital to controlling its transmission to humans as well as to other animal groups. Objectives: This systematic review and meta‐analysis aims to summarise and analyse reports of T. gondii infection in animal species residing in the Arabian Peninsula. Methods: : It was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA), with relevant studies being retrieved from MEDLINE/PubMed, Scopus, Cochrane Library, Google Scholar and ScienceDirect. All articles published in Arabic or English languages between January 2000 and December 2020 were screened for eligibility. Random effects model was used to calculate the pooled prevalence of T. gondii infection in different animal populations which were found to harbour this infection. The critical appraisal tool for prevalence studies designed by the Joanna Briggs Institute (JBI) was used to assess the risk of bias in all included studies. Results: A total of 15 studies were retrieved, reporting prevalence estimates from 4 countries in this region and in 13 animal species. Quantitative meta‐analysis estimated a pooled prevalence of 43% in felids [95% confidence interval (CI) = 23–64%, I2 index = 100%], 48% in sheep (95% CI = 27–70%, I2 = 99%) and 21% in camels (95% CI = 7–35%, I2 = 99%). Evidence of possible publication bias was found in both felids and sheep. Conclusions: This meta‐analysis estimates a high prevalence of T. gondii infection in animal species which are of high economic and cultural importance to countries of this region. Hence, these findings provide valuable insight to public health authorities as well as economic and animal resources advisors in countries of the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

Background: Lumpy skin disease (LSD) is a highly infectious disease of cattle caused by a virus of the Poxviridae family, genus Capripoxvirus. The disease has great economic effects on the global cattle industry. In this study, an outbreak of LSD among cattle which occurred in Nahr Atbara and Halfa El Jadida locations in Butana area, Kassala State in November, 2020 is described. Methods: Lumpy skin disease virus (LSDV) antibody and nucleic acid were detected in specimens (n = 50) using enzyme‐linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). Results: The virus was isolated on the chorioallantoic membrane (CAM) of embryonated chicken eggs and identified by PCR. The number of animals at risk was 295 with a morbidity rate of 4.1% and a mortality rate of 2.4%. Conclusions: LSDV was diagnosed for the first time in the Butana region, Kassala State, Eastern Sudan in 2020. [ABSTRACT FROM AUTHOR]

Crop wild relatives (CWRs) of carrot (Daucus. carota L.) including 64 germplasm accessions of D. carota L. subsp. carota, D. carota L. subsp. capillifolius (Gilli) Arbizu, and D. carota L. subsp. gummifer (Syme) Hook. f., as well as two accessions of another 18‐chromosome species, D. syrticus Murb., were grown in field trials to flowering under conditions of heat, drought, and salinity stress in Bangladesh and Pakistan. Plant growth before floral initiation was evaluated and plants were allowed to progress to flowering to evaluate seed production. A wide range of response was observed among entries ranging from no germination or plant death early in development to vigorous growth. Carrot grown under optimal conditions in the greenhouse served as a useful control to estimate tolerance indices in the field. New sources of heat and drought tolerance in subsp. carota and subsp. capillifolius accessions were identified with similar performance in both countries. Ecogeographic analysis demonstrated that environmental parameters at the collection location of germplasm were associated with heat and drought tolerance observed in field trials. Plants evaluated for tolerance were allowed to flower and seed was produced on selected plants with abiotic stress tolerance to develop populations or breeding pools and to initiate the development of carrot better adapted to climatic abiotic stress. [ABSTRACT FROM AUTHOR]

In its occult form, hepatitis B virus infection can only be detected using molecular techniques such as polymerase chain reaction, increasing the cost of the screening process. Certain population subgroups are considered to have a higher risk of transmission and reactivation of occult hepatitis B virus infection (OBI). This review aims to estimate the prevalence of OBI among these high‐risk groups in Sudan. It was conducted under the PRISMA guidelines, targeting the literature available in MEDLINE/PubMed, ScienceDirect, Google Scholar, and Cochrane Library databases. Full‐text articles published in the last 10 years that provide prevalence estimates of OBI in Sudan were examined for fulfillment of eligibility criteria. Quality assessment of selected articles was performed using the critical appraisal tool reported by Munn et al. Publication bias was assessed by visual examination of the funnel plot. Meta‐analysis using the random‐effects model with 95% confidence interval was used to calculate the overall and subgroup pooled prevalence of OBI. Literature search yielded a total of 717 studies, of which only 11 articles fulfilled all selection criteria. The overall pooled prevalence of OBI was found to be 15.51%, with a high level of heterogeneity. Subgroup analysis demonstrated a prevalence of 16.48% among blood donors, 13.36% among hemodialysis patients, and 12.59% among febrile patients. Evidence for possible publication bias was detected. This review provides crucial evidence for health authorities in Sudan, outlining the necessity for re‐evaluation of the current screening strategies, especially among these high‐risk groups. [ABSTRACT FROM AUTHOR]

Background: Weaning from parenteral support is considered indirect evidence of intestinal adaptation in patients with short bowel syndrome (SBS), but direct evidence is lacking. The objective of this study was to examine if intestinal adaptation could be demonstrated as increase in intestinal absorption of energy and wet weight over time measured by repeated metabolic balance studies (MBSs) and to examine whether adaptation was determined by the anatomy of the remnant bowel.Methods: We retrospectively analyzed data from 48 repeated MBSs performed in 13 adult patients with SBS. Results were presented graphically and interpreted. The interpatient and intrapatient heterogeneity was compared based on anatomy of the remnant bowel.Results: The number of repeated MBSs ranged from 2 to 7, and time between last intestinal resection and MBS from 5 months to 18.1 years. In 6 patients, the first MBS was performed within 2 years after last resection, but only 1 patient had repeated MBSs within this period. Nine patients had an end jejunoileostomy, and 4 patients had a jejuno-colonic or ileo-colonic anastomosis. None of the patients had jejunoileal anastomosis with a preserved ileocecal valve. Interpatient and intrapatient heterogeneity of wet weight and energy absorption was larger in patients without colon in continuity. The wet weight and energy absorption data showed no tendency toward intestinal adaptation in any anatomical group.Conclusion: We observed no signs of late-phase intestinal adaptation in this selected group of patients with SBS. Future prospective MBSs are needed to understand the time course and magnitude of intestinal adaptation. [ABSTRACT FROM AUTHOR]

Background: Reticuloendotheliosis virus (REV) is a gammaretrovirus that belongs to the family of Retroviridae. The infection can result in immunosuppression, runting syndrome, high mortality, acute reticular cell neoplasia or T‐ and/ or B‐cell lymphoma, in a variety of domestic and wild birds. The disease is widespread around the world. No related data have been reported in Sudan about the disease. The present study was conducted to determine the prevalence of REV antibodies and DNA in local and commercial breeds of chickens older than 20 weeks from June 2014 to February, 2017. Methods: A total of 460 sera samples and 150 (50 liver and 100 spleen) tissue samples were collected from local and commercial breeds of chickens older than 20 weeks and screened for anti‐REV antibodies in four states of Sudan using a commercial REV antibody ELISA test kit (IDEXX). Polymerase chain reaction (PCR) was performed to detect REV DNA in tissue samples in Khartoum State. Results: The results revealed that the overall seroprevalence of REV was 74.6% among local and commercial chicken breeds, but in commercial it was 79.5% (190/239) and 69.2% in local breeds (153/221). One hundred and fifty tissue samples of chickens (50 liver, 100 spleen) were tested using PCR for detection of REV using primer sets of the conserved region in envelope glycoprotein (env) gene with a band length of 850 bp. Five out of 50 (10%) liver samples were RE provirus DNA positive detected by PCR, whereas 15 out of 100 (15%) spleen samples were PCR positive. Univariate analysis revealed there was a difference (p ≤ 0.05) between locality and breed of chickens and seropositivity to REV. Conclusions: The prevalence of the disease was high in Sudan and more studies are needed to evaluate the epidemiology and pathogenesis of the virus. [ABSTRACT FROM AUTHOR]

Background/aims: Catheter-related complications (CRCs) cause mortality and morbidity in patients dependent on parenteral support at home (HPN) due to intestinal failure (IF). This study describes the incidences of CRCs in an adult IF cohort over 40 years. It illustrates the evolution and consequences of CRCs, their association to demographic characteristics, and potential risk factors in an effort to provide the rationale for preventive precautions to the relevant patients with IF at risk.Methods: All patients with IF discharged with HPN from 1970-2010 were included. Patient and treatment characteristics were extracted from the Copenhagen IF database. The incidences were given per 1000 central venous catheter (CVC) days.Results: The 1715 CRCs occurred in 70% of the 508 patients with IF (56% of the 2191 CVCs). The incidence of catheter-related bloodstream infections (CRBSIs) was 1.43. Higher age, HPN administration by community home nurses, and prior CRBSIs significantly raised the hazard for CRBSIs. In the 1970s, catheters were generally replaced following CRBSIs, whereas catheter salvage was the norm in the 2000s. The incidences of mechanical complications, tunnel infections, and catheter-related venous thromboses were 0.80, 0.25, and 0.11, respectively. The overall CRC incidence was 2.58, decreasing the first 3 decades but peaking in the last (2.84). The deaths related to CRCs were low (0.018).Conclusion: Even in an experienced IF center of excellence, the incidence of CRCs increased over the 4 decades. This increase could be explained by the expansion of the indication of HPN to a more elderly and frail patient population. [ABSTRACT FROM AUTHOR]

Background/aims: In Denmark, the public healthcare system ensures patients with intestinal failure (IF) the same rights for a life-saving treatment as patients with other organ failures. This study reports the epidemiological data from the largest Danish IF center. As one of the pioneering centers in treating IF with home parenteral nutrition (HPN), this study documents the HPN evolution and describes the demographics and outcome in one of the world's largest single-center cohorts.Methods: We included patients with IF discharged with HPN from 1970-2010. Data were extracted according to European Society for Clinical Nutrition and Metabolism classifications from the Copenhagen IF database.Results: Over the decades, we observed an exponential increase in the number of HPN patients. The 508 patients with IF collectively received HPN for 1751 years. While receiving HPN, 211 patients with IF (42%) died. Only 24 deaths were HPN related: sepsis (n = 10), liver disease (n = 12), central venous thrombosis (n = 1), and a complicated catheter placement (n = 1). The HPN-related mortality was as low as 0.014 deaths/HPN year. In the first decade, HPN was mainly provided to younger, intestinally resected adult patients with IF with inflammatory bowel disease (IBD), but numerically, they were subsequently outnumbered by elderly patients with IF with cancer or complications from non-IBD, noncancer abdominal surgery. Despite these demographic changes, the HPN-related mortality has decreased in the past decade.Conclusion: Evolving from being a rare, experimental treatment in the 1970s, HPN at present is safe with a low treatment-related mortality in the experienced center, despite HPN being more widely used in a more elderly population. [ABSTRACT FROM AUTHOR]

Spotted fever group ( SFG) rickettsiosis is caused by obligatory intracellular Gram-negative bacteria that belong to the genus Rickettsia. Ticks belonging to the family Ixodidae can act as vectors, reservoirs or amplifiers of SFG rickettsiae. This study was conducted to estimate the seroprevalence of SFG rickettsioses in cattle, sheep and goats from Khartoum State, Sudan. Blood samples were collected from a total of 600 animals (sheep, goats and cattle) from 32 different farms distributed in three locations in Khartoum State during the period January to December 2012. Sera were tested for antibodies against SFG rickettsiae using IFAT. The prevalence of seropositivity was 59.3% in sheep, 60.1% in goats and 64.4% in cattle. Season was significantly ( P < 0.05) associated with seroprevalence of SFG rickettsiae in cattle during winter. The SFG rickettsiae antibodies prevalence was significantly higher in female compared with male in sheep, but there were no significant differences between male and female in either cattle or goats. The prevalence was significantly higher in adult animals compared with young in both sheep and goats. With regard to management system, there was a significant difference in the prevalence in cattle raised in closed system compared with those raised in semi-intensive system. In contrast, there was significant difference in the seroprevalence of SFG in sheep where the prevalence was higher in the sheep raised in semi-intensive system compared with those raised in close system. There was no significant difference in the seroprevalence in goats with regard to management systems. The unexpected high prevalence of SFG rickettsia antibodies in domestic ruminants sera suggest that the veterinary and public health impact of these agents in Sudan need further evaluation especially in humans. [ABSTRACT FROM AUTHOR]

ABSTRACT A dual band Artificial Magnetic Conductor (AMC) with capacitive tuning of reflection phase at lower band frequency is proposed. The AMC operates at upper band of fixed frequency at 5.8 GHz while the lower band reconfigurable frequency is from 2.5 GHz up to 3.1 GHz. The simulated reconfigurable frequencies are 2.5, 2.62, and 3.10 GHz. The corresponding resonance structure for each band is circular patch and circular slotted ring with single capacitor per AMC unit cell. Subsequently, the AMC is incorporated with conventional UWB antenna. The effects of AMC capacitive tuning to UWB antenna performance are studied in terms of frequency reconfigurability, gain, and radiation patterns. Measurement is also carried out for the reflection coefficient and radiation patterns. Parametrical studies of the antenna such as the misalignment between the top and bottom substrate layers, air gap between the substrate layers, and capacitance tolerance of the capacitor to the reflection coefficients are also discussed. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2422-2429, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT A wideband antenna fed by a coplanar waveguide (CPW) with reconfigurable function is presented. The wideband function is achieved from 1.39 GHz to 8.11 GHz using an elliptical radiator with a CPW feed line. Meanwhile, three pairs of slot dipoles which are fed by CPW are used to achieve triple-band function at 2.4 GHz, 3.5 GHz and 5.2 GHz. Four ideal switches are placed on the proposed antenna. The proposed antenna is designed, simulated, fabricated and tested. All simulated and measured results of return loss, radiation pattern and gain are presented. Good results of return loss and radiation pattern are obtained thus verifying that the proposed antenna is suitable for future multimode radio systems. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2079-2082, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a technique to enhance the bandwidth of a rectangular dielectric resonator antenna using a circular slot. The structures are designed and simulated using CST Microwave Studio software, and it is found that the circular slot exhibits a bandwidth of 36.44% (0.92-1.33 GHz). The circular slot is compared with the rectangular slot. It is shown that the rectangular slot produces a bandwidth of 6.39% (1.06-1.13 GHz). Both structures exhibit similar radiation patterns with slightly different gains at 3.10 and 3.25 dBi. The bandwidth is enhanced more than five times using the circular slot, compared to the rectangular slot. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:506-509, 2016 [ABSTRACT FROM AUTHOR]

ABSTRACT A composite right-/left-handed transmission line metamaterial antenna with enhanced bandwidth and efficiency is proposed. The antenna combines zeroth-order resonant (ZOR) and positive-order resonant (POR) modes for the bandwidth enhancement. An asymmetrical coplanar waveguide technique is used to feed the antenna and also to achieve certain degree of compactness. The overall size of the antenna is 0.32λ0 × 0.38λ0 × 0.012λ0 (40 × 48 × 1.52 mm) at 2.4 GHz. Simulation results show that a bandwidth enhancement of 41% is obtained with the radiation efficiencies of 95 and 97% for the ZOR and POR modes, respectively. The measured impedance bandwidth shows that the antenna has potential applications for WLAN (2.39-2.45 GHz) and WiMAX (2.5-2.69 GHz) operations. The simulated and measured antenna performances in terms of return loss and the radiation patterns are presented and compared. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:252-256, 2015 [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Should all mucosal head and neck cancer patients be treated in high volume centres, or can some be appropriately triaged to local centres for treatment," by J. Corry in a 2016 issue.

ABSTRACT In this article, a duals-band metamaterial antenna with a new composite right/left-handed (CRLH) unit cell configuration is proposed. The antenna is a coplanar waveguide (CPW) base which uses quarter wave resonators without via. Both sides of the CPW ground plane are short circuited to the CRLH-transmission line. The dimension is 31 mm × 22 mm × 1.52 mm, with electrical size of 0.23 λo × 0.17 λo × 0.011 λo at 2.26 GHz, and which is compact in size. Resonance frequency of the negative mode can be altered by controlling the loop currents. Peak gains of 1.74 and 2.69 dBi are obtained at 2.26 and 2.89 GHz. Radiation efficiencies of 64% and 92% are obtained at 2.26 and 2.89 GHz, respectively. The simulated and measured return losses, as well as the radiation patterns, are presented and compared. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1575-1579, 2014 [ABSTRACT FROM AUTHOR]

The present study was designed to test the relationship between business leaders' social intelligence ( SI) and their creative performance ( CP) in the US. SI was defined as the ability to be aware of relevant social situational contexts; to deal with situational contexts or challenges effectively; to understand others' concerns, feelings and emotional states; and to build and maintain positive relationships and to behave appropriately in social relations. Data on SI and CP were collected using questionnaires from two collegiate samples of employed undergraduate students ( n = 395) and employed MBA students ( n = 250) and from a sample of top executives of organizations ( n = 143) to explore the relationship between leaders' SI and their CP. The questionnaires required observers (i.e., respondents) to indicate to what extent their supervisors displayed SI and CP. Data analyses in each sample suggest that supervisors with greater social intelligence contributed more to CP. Implications for management, directions for future research and limitations of the study are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT A new reconfigurable multiband antenna is presented. The antenna operates in triple band and can be switched to operate either in single or dual band. The multifrequency band is achieved by using slots dipole antenna fed by a coplanar waveguide (CPW). Six switches are used and positioned at specific locations in the slots to achieve frequency reconfigurability. The antenna reconfiguration is realized when the dipole arms are coupled or decoupled from the slot edges. Three different sub-band frequencies (2.40, 3.50, and/or 5.20 GHz) are obtained. Measured and simulated results are presented. The proposed antenna may be suitable for future multimode applications such as cognitive radio systems. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:735-740, 2014 [ABSTRACT FROM AUTHOR]

In the present work, a computer-controlled test rig for simultaneous fatigue testing of several pseudoelastic NiTi wires through bending rotation is described. Bending rotation fatigue (BRF) testing represents a displacement-controlled experiment where a straight wire is bent into a semi-circle und forced to rotate around its axis. Thus, each point on the wire surface is subjected to alternating tension and compression. A test rig, which allows to control loading amplitudes, rotation frequencies and temperatures is described. We report preliminary results of an experimental program, which aims for a better understanding of fatigue lives, crack initiation, and crack growth in pseudoelastic NiTi wires. It was found that a good surface quality is of utmost importance to avoid early crack initiation. Wöhler curves of pseudoelastic NiTi wires typically show two different regimes depending on the maximum imposed surface strain during bending rotation fatigue testing. Larger strain amplitudes, which are associated with macroscopic formation of stress-induced martensite, result in relatively low fatigue lives (LCF regime). In contrast, cycle numbers exceeding 107 were obtained for strain amplitudes where no large scale stress-induced formation of martensite occurred (HCF regime). [ABSTRACT FROM AUTHOR]

This article presents the design, simulation, and fabrication of a new planar left-handed metamaterial (LHM), which consist of a combination of a modified square rectangular split ring resonator and strip wire. Both structures are on the same plane. The structure is simulated and measured with the microstrip antenna operating at frequency 5.8 GHz. The LHM has been analyzed using Nicolson-Ross-Weir approach to obtain the negative permeability and permittivity at 5.8 GHz. The fabrication of the LHM is on FR-4 board substrate. From the simulation and measurement results, the gain of the microstrip antenna with LHM has increased by 4.0 dB. The return loss of the antenna with LHM is improved to 15.7 dB compare without LHM structure. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2828-2832, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27186 [ABSTRACT FROM AUTHOR]

As well as for chemical and environmental reasons, acrylamide is widely used in many industrial applications. Due to its carcinogenicity and toxicity, its discharge into the environment causes adverse effects on humans and ecology alike. In this study, a novel acrylamide-degrading yeast has been isolated. The isolate was identified as Rhodotorula sp. strain MBH23 using ITS rRNA analysis. The results showed that the best carbon source for growth was glucose at 1.0% (w/v). The optimum acrylamide concentration, being a nitrogen source for cellular growth, was at 500 mg l-1. The highest tolerable concentration of acrylamide was 1500 mg l-1 whereas growth was completely inhibited at 2000 mg l-1. At 500 mg l-1, the strain MBH completely degraded acrylamide on day 5. Acrylic acid as a metabolite was detected in the media. Strain MBH23 grew well between pH 6.0 and 8.0 and between 27 and 30 °C. Amides such as 2-chloroacetamide, methacrylamide, nicotinamide, acrylamide, acetamide, and propionamide supported growth. Toxic heavy metals such as mercury, chromium, and cadmium inhibited growth on acrylamide. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

A novel hybrid dielectric resonator antenna (DRA) excited by a printed monopole antenna is proposed and implemented. This new microstrip-fed fork-like stepped monopole antenna is designed to obtain a wide impedance bandwidth from 2 to 6 GHz. A quad-band characteristic is achieved by incorporating two modified cylindrical dielectric resonators with a high dielectric constant of 80, on top of the monopole exciter. Measured results demonstrated that the proposed DRA can be used in multiband wireless operations, covering GSM, PCS, UMTS, WLAN, and WiMax systems, from 1.75 to 5.85 GHz. Experimental and simulation results show a good agreement. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2887-2890, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26407 [ABSTRACT FROM AUTHOR]

In this article, the design of log periodic fractal Koch antenna using the second iteration has been developed for ultra high frequency band applications. The ability to reduce the size as maintaining the performances of the antenna such as input return loss and radiation patterns brings fractal Koch and becomes enticing among researchers. The design of the log periodic fractal Koch antenna has been elaborated in this article. The computer simulation technology software has been used to analyze the performances of the designed antenna. This has been compared between simulation and measurement. The results show that this antenna has been reduced by up to 27% in size from the normal log periodic planar dipole antenna. The performance of the antenna has been compared in terms of return losses, bandwidths, and radiation patterns. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26111 [ABSTRACT FROM AUTHOR]

In this article, we propose a new statistic to control the covariance matrix of bivariate processes. This new statistic is based on the sample variances of the two quality characteristics, in short VMAX statistic. The points plotted on the chart correspond to the maximum of the values of these two variances. The reasons to consider the VMAX statistic instead of the generalized variance |S| are its faster detection of process changes and its better diagnostic feature, that is, with the VMAX statistic it is easier to identify the out-of-control variable. We study the synthetic chart based on the VMAX statistic. The proposed chart is always more efficient than the chart based on the generalized variance |S|. An example is presented to illustrate the application of the proposed chart. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

To describe differences in prevalence of Type 2 diabetes mellitus with its associated risk factors between rural and urban populations in Bangladesh. Diagnostic criteria [fasting blood glucose (FBG) and oral glucose tolerance tests (OGTT)] were compared and reviewed for both populations. A total of 1555 subjects from urban and 4757 from rural communities (age ≥ 20 years) with similar cultural and ethnic backgrounds were randomly selected in a cross-sectional survey. FBG values were determined from all and 2-h post-glucose capillary blood samples were determined after a 75-g oral glucose load for a selected number (urban 476, rural 1046). A higher prevalence of diabetes was found in urban (8.1%) compared with rural populations (2.3%). Age, sex and waist-to-hip ratio for men were significant risk factors for both urban and rural subjects following fasting and 2-h post-glucose values adjusted for a number of confounding variables. Poor agreement was observed between FBG and OGTT for both urban (kappa 0.41) and rural (kappa 0.40) areas. A higher prevalence of diabetes mellitus (DM) in the urban population was observed compared with rural subjects despite similar body mass indexes (BMI). Differences in obesity, waist/hip ratio or hypertension failed to explain the increasing occurrence of T2DM in the urban population. Diabet. Med. 22, 931–936 (2005) [ABSTRACT FROM AUTHOR]

When joint ―X and R charts are in use, samples of fixed size are regularly taken from the process, and their means and ranges are plotted on the ―X and R charts, respectively. In this article, joint ―X and R charts have been used for monitoring continuous production processes. The sampling is performed, in two stages. During the first stage, one item of the sample is inspected and, depending on the result, the sampling is interrupted if the process is found to be in control; otherwise, it goes on to the second stage, where the remaining sample items are inspected. The two-stage sampling procedure speeds up the detection of process disturbances. The proposed joint ―X and R charts are easier to administer and are more efficient than the joint ―X and R charts with variable sample size where the quality characteristic of interest can be evaluated either by attribute or variable. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study presents an integrated model for the joint economic design of $\overline{x}$-control charts and maintenance schedules and, simultaneously, determines the economic production quantity and production run length for a deteriorating production system. The operating state of the production process is classified as either in control or out of control. In the latter state, the process produces some defective items. An $\overline{x}$-control chart is used to monitor the process mean. Both uniform and non-uniform inspection schemes are adopted. Inspection and maintenance are performed simultaneously. Replacement cost is assumed to be very high. The process failure mechanism is assumed to follow a general probability distribution with an increasing failure rate. The concept of a truncated production cycle is introduced. The production cycle begins when a new component is installed and ends with a repair after the detection of a failure or after a specified number of inspection intervals, $m$, whichever occurs first. The effects of preventive maintenance on quality control are discussed. Numerical examples are provided to evaluate the performance of the model. Sensitivity analyses are conducted to study the effects of various model parameters. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Sunflower downy mildew (SDM) caused by Plasmopara halstedii , is a major disease of sunflower. Eleven resistance genes have been identified, but allelic relationships among these genes are not clear. This study examined the inheritance and allelic relationships of genes conferring resistance to SDM races 1, 2 and 3 (virulence phenotypes 100, 300 and 700, respectively) and confirmed a twelfth resistance gene. Three USDA Plant Introductions, AMES 3235, PI 497250, and PI 497938, and three released lines, RHA 266, RHA 274 and DM-2 were studied. RHA 266 has only the Pl 1 gene for race 1 resistance. Digenic inheritance of resistance was found in AMES 3235, PI 497250, and RHA 274. These lines have the Pl 1 and Pl 12 genes, conferring resistance to race 1, and the Pl 2 and Pl 11 genes, conferring resistance to race 2. DM-2 and PI 497938 have Pl 12 (but not Pl 1) for resistance to race 1, the Pl 12 gene (but not the Pl 2) for resistance to race 2, and Pl 5 for resistance to race 3. These resistance genes will serve as a foundation for future gene designations and genetic diversity studies of resistance to SDM. [ABSTRACT FROM AUTHOR]

This paper considers the optimal determination of the length of the production run and the initial setting of a process that exhibits a linear drift that can start at a random point in time. Quadratic off-target costs and time-based costs of maintenance and salvage value are included in the formulation. The model includes other models proposed in the literature as particular cases. Numerical examples are provided to illustrate the application of the proposed model. Copyright © 2001 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper considers the problem of a continuous production process where both the mean and variance are simultaneously monitored by an &Xmacr; and R chart respectively, and generalizes the model of Costa (IIE Transactions 1993; 25(6):27–33). The product variable quality characteristic is assumed to be normally distributed and the process is subject to two independent assignable causes (such as tool wear-out, overheating or vibration). One cause changes the process mean and the other changes the process variance. However, the occurrence of one kind of assignable cause does not preclude the occurrence of the other. It is also assumed that the occurrence times of the assignable causes are described by Weibull distributions with increasing failure rates. A cost model is developed and a non-uniform sampling interval scheme is adopted. A two-step search procedure is employed to determine the optimal design parameters. The relative contribution of the paper over the results obtained by Costa is addressed. A sensitivity analysis of the model is conducted and the cost savings associated with the use of non-uniform sampling intervals instead of constant sampling intervals are evaluated. The economic design model is then extended to an economic–statistical design model for achieving desired levels of statistical performance while minimizing the expected cost. Performances of purely economic design and economic–statistical design are compared. Copyright © 2000 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study tested the relationships of bases of leader power (coercive, reward, legitimate, expert, and referent) to subordinates' organizational commitment and of power bases and commitment to subordinates' effectiveness (performance, conformance, dependability, and personal adjustment). Two hundred fifty employees and their supervisors from three banks in Bangladesh were individually interviewed to fill out the Rahim Leader Power Inventory, Organizational Commitment Questionnaire, and Minnesota Satisfactoriness Scales, to measure power, commitment, and effectiveness, respectively. Two stepwise hierarchical regression analyses showed that legitimate and expert power bases were positively associated with commitment. Coercive power was negatively associated with effectiveness and expert power was positively associated with the same. Implications of the findings for international managers working in developing countries are discussed. [ABSTRACT FROM AUTHOR]

The polymorphic region of the Theileria annulata surface protein ( TaSP) was cloned and sequenced from different isolates of cattle and cell lines from different areas of Sudan. Amino acid sequence alignment revealed a high diversity showing amino acid and length polymorphism, both within and between parasite isolates. The generation of TaSP diversity may allow the evasion of host immunity by the parasite since TaSP is a highly antigenic parasite protein. [ABSTRACT FROM AUTHOR]

Feed spacers improve mixing and mass transfer in membrane modules. However, they also lead to foulant deposition in the vicinity of the spacer surface. In this paper, two hydrophilic monomers, namely, acrylic acid (AA) and 2‐hydroxyethyl methacrylate (HEMA), are respectively coated on the surface of a commercial feed spacer via a plasma‐enhanced chemical vapor deposition (PECVD) method. The resulting modified spacers are then evaluated alongside with a reverse osmosis (RO) membrane for its solute rejection, water permeability, and antifouling properties. Results show that the surface hydrophilicity of feed spacers has been enhanced upon the AA and HEMA deposition. During filtration test, the HEMA‐modified spacer demonstrates higher flux recovery rate (94.17%) and salt rejection (95.78%) for the RO membrane. In contrast, the membrane with the unmodified spacer only shows 89.44% and 92.46%, respectively. Additionally, the membrane with the HEMA‐modified spacer has a thinner fouling layer (200 nm) compared to the unmodified spacer (700 nm). The HEMA‐coated spacer outperforms all the tested spacers, demonstrating that feed spacer modification with a hydrophilic monomer via the PECVD method can effectively reduce membrane fouling. [ABSTRACT FROM AUTHOR]

A textile artificial magnetic conductor (AMC) waveguide sheet with a textile diamond dipole is proposed to improve wireless on-body transmission. The sheet-like waveguide provides an independent transmission path which can reduce the performance degradation caused by the human body. The proposed AMC sheet is made entirely of textiles for both the substrate and the conducting parts, thus making it suitable for wearable communications. Transmission characteristics between antennas are studied rigorously in free space and on-body environments. Significant transmission enhancement is observed for all the tested orientations and positions for both free space and onbody placements. With the presence of the AMC, the S21 has peaks of up to a maximum of -9.9 dB. This textile AMC sheet constitutes a new approach for efficient wearable wireless body-centric communications. [ABSTRACT FROM AUTHOR]

A slot dipole antenna with a reconfigurable operating frequency is presented. The antenna comprises two pairs of slot arms. Each arm incorporates a number of varactor diodes. The antenna is capable of operating in single-band or dual-band mode. In each case, the location of these bands can be altered by varying the voltage applied to the varactor diodes. The antenna can be tuned over a wide frequency range, namely 1.5-4.5 GHz (i.e. a ratio of 3:1). The antenna is potentially useful for cognitive radio application, particularly in a small base station or access point terminal. [ABSTRACT FROM AUTHOR]

A small electrical metamaterial (MTM) antenna, based on a modified electrical coupled resonator for bandwidth enhancement, is presented. The bandwidth enhancement is achieved using a modified electric coupled (MELC) resonator as the antenna's main radiating element. This modification is achieved using two strip lines placed below a conventional electric coupled (CELC) resonator. The measured impedance bandwidth at -10 dB is 20.7% at a resonance frequency of 2.62 GHz. The design is validated by experimental results, and the proposed antenna is suitable for worldwide interoperability for microwave access (WiMax) applications (2.5-2.69 GHz). [ABSTRACT FROM AUTHOR]