Pre-treatment with antiarrhythmic drugs for elective electrical cardioversion of atrial fibrillation: a systematic review and network meta-analysis.

AIMS: Our objective was to compare the efficacy of pre-treatment with different classes of anti-arrhythmic drugs (AADs) in patients with atrial fibrillation (AF) undergoing electrical cardioversion. METHODS AND RESULTS: We performed a systematic review and network meta-analysis (NMA) of randomized controlled trials (RCTs) comparing different AADs in patients with AF undergoing electrical cardioversion. We grouped AADs into five network nodes: no treatment or rate control, Class Ia, Class Ic, Class III, and amiodarone. Outcomes were (i) acute restoration and (ii) maintenance of sinus rhythm. We searched MEDLINE and EMBASE from inception until June 2020. We used Python 3.8.3 and R 3.6.2 for data analysis. We evaluated the overall certainty of evidence with the GRADE framework. We included 28 RCTs. Compared with no treatment or rate control, Class III AADs [odds ratio (OR): 2.41; 95% credible interval (CrI): 1.37 to 4.62, high certainty] and amiodarone (OR: 2.58; 95% CrI: 1.54 to 4.37, high certainty) improved restoration of sinus rhythm. Amiodarone improved long-term maintenance of sinus rhythm when compared with no treatment or rate control (OR: 5.37; 95% CrI: 4.00-7.39, high certainty), Class Ic (OR: 1.89; 95% CrI: 1.05-3.45, moderate certainty) and Class III AADs (OR: 2.19; 95% CrI: 1.39-3.26, high certainty). CONCLUSION: Before electrical cardioversion of AF, treatment with Class III AADs or amiodarone improves the acute restoration of sinus rhythm. Amiodarone is most likely to improve the maintenance of sinus rhythm after electrical cardioversion, but Class Ic and Class III AADs are also effective.

Unexpected Phonon Behaviour in BiFexCr1-xO3, a Material System Different from Its BiFeO3 and BiCrO3 Parents.

The dielectric function and the bandgap of BiFe0.5Cr0.5O3 thin films were determined from spectroscopic ellipsometry and compared with that of the parent compounds BiFeO3 and BiCrO3. The bandgap value of BiFe0.5Cr0.5O3 is lower than that of BiFeO3 and BiCrO3, due to an optical transition at ~2.27 eV attributed to a charge transfer excitation between the Cr and Fe ions. This optical transition enables new phonon modes which have been investigated using Raman spectroscopy by employing multi-wavelengths excitation. The appearance of a new Raman mode at ~670 cm-1 with a strong intensity dependence on the excitation line and its higher order scattering activation was found for both BiFe0.5Cr0.5O3 thin films and BiFexCr1-xO3 polycrystalline bulk samples. Furthermore, Raman spectroscopy was also used to investigate temperature induced structural phase transitions in BiFe0.3Cr0.7O3.

Imaging Utilization Patterns and Injury Characteristics Associated with Electric Standing Scooters in a Major Urban Area.

BACKGROUND: The recent proliferation of electric standing scooters in major urban areas of the United States has been accompanied by injuries of varying severity and nature, representing a growing public health concern. OBJECTIVE: Our aim was to characterize imaging utilization patterns for injuries associated with electric scooter (e-scooter) use, including their initial emergency department (ED) management. METHODS: We conducted a retrospective review of the electronic medical record for all patients presenting to affiliated EDs for e-scooter-related injuries between July 2018 and April 2020. Demographics, date and time of presentation, imaging study type, resultant injury, and procedural details were recorded. RESULTS: Ninety-seven patients were included; mean age was 27.6 years. Of these, 55 patients (57%) had injuries identified on imaging and 40% of all imaging studies were positive. Most identified injuries (61%) were musculoskeletal, with a small number of neurological (2%) and genitourinary (1%) injuries. The highest prevalence of presentations occurred in August; most patients (72%) presented between 3 pm and 1 am and granular peaks were between 12 am and 1 am and 5 pm and 6 pm. CONCLUSIONS: Patients presenting with e-scooter injuries have a high likelihood of injury to the radial head, nasal bone, and malleoli. Emergency physicians should be especially vigilant for injuries in these areas at presentation. Visceral injuries are uncommon but may be severe enough to warrant surgery.

Strongly enhanced and tunable photovoltaic effect in ferroelectric-paraelectric superlattices.

Ever since the first observation of a photovoltaic effect in ferroelectric BaTiO3, studies have been devoted to analyze this effect, but only a few attempted to engineer an enhancement. In conjunction, the steep progress in thin-film fabrication has opened up a plethora of previously unexplored avenues to tune and enhance material properties via growth in the form of superlattices. In this work, we present a strategy wherein sandwiching a ferroelectric BaTiO3 in between paraelectric SrTiO3 and CaTiO3 in a superlattice form results in a strong and tunable enhancement in photocurrent. Comparison with BaTiO3 of similar thickness shows the photocurrent in the superlattice is 103 times higher, despite a nearly two-thirds reduction in the volume of BaTiO3 The enhancement can be tuned by the periodicity of the superlattice, and persists under 1.5 AM irradiation. Systematic investigations highlight the critical role of large dielectric permittivity and lowered bandgap.

Incidence and recurrence of new-onset atrial fibrillation detected during hospitalization for non-cardiac surgery: a systematic review and meta-analysis.

PURPOSE: This systematic review aimed to summarize reports of the incidence and long-term recurrence of new-onset atrial fibrillation (AF) associated with non-cardiac surgery. SOURCES: We searched CENTRAL, MEDLINE and EMBASE from inception to November 2019. We included studies that reported on the incidence of new-onset perioperative AF during hospitalization for non-cardiac surgery and/or AF recurrence in such patients following discharge. Reviewers screened articles and abstracted data independently and in duplicate. We assessed study quality by appraising methodology for collecting AF history, incident AF during hospitalization, and AF recurrence after discharge. PRINCIPAL FINDINGS: From 39,233 citations screened, 346 studies that enrolled a total of 5,829,758 patients met eligibility criteria. Only 27 studies used prospective, continuous inpatient electrocardiographic (ECG) monitoring to detect incident AF. Overall, the incidence of postoperative AF during hospitalization ranged from 0.004 to 50.3%, with a median [interquartile range] of 8.7 [3.8-15.0]%. Atrial fibrillation incidence varied with type of surgery. Prospective studies using continuous ECG monitoring reported significantly higher incidences of AF than those that did not (13.9% vs 1.9%, respectively; P < 0.001). A total of 13 studies (25,726 patients) with follow-up up to 5.4 years reported on AF recurrence following hospital discharge; only one study used a prospective systematic monitoring protocol. Recurrence rates ranged from 0 to 37.3%. CONCLUSIONS: Rates of AF incidence first detected following non-cardiac surgery and long-term AF recurrence vary markedly. Differences in the intensity of ECG monitoring and type of surgery may account for this variation. TRIAL REGISTRATION: PROSPERO (CRD42017068055); registered 1 September 2017.

RéSUMé: OBJECTIF: Cette revue systématique visait à résumer les comptes rendus sur l'incidence et la récurrence à long terme de la fibrillation auriculaire (FA) de novo associée à une chirurgie non cardiaque. SOURCES: Nous avons effectué des recherches dans les bases de données CENTRAL, MEDLINE et EMBASE de leur création à novembre 2019. Nous avons inclus les études ayant examiné l'incidence de nouvelle FA périopératoire pendant l'hospitalisation pour une chirurgie non cardiaque et/ou la récurrence de la FA chez de tels patients après leur congé. Les chercheurs ont passé en revue les articles et les données extraites de manière indépendante et en double. Nous avons estimé la qualité des études en évaluant la méthodologie de collecte des antécédents de FA, de l'incident de FA pendant l'hospitalisation et de la récurrence de FA après le congé. CONSTATATIONS PRINCIPALES: Sur les 39 233 citations examinées, 346 études portant sur un total de 5 829 758 patients ont répondu à nos critères d'admissibilité. Seulement 27 études ont utilisé un monitorage électrocardiographique (ECG) continu prospectif et des patients hospitalisés pour détecter les incidents de FA. Dans l'ensemble, l'incidence de FA postopératoire pendant l'hospitalisation allait de 0,004 à 50,3 %, avec une médiane [écart interquartile] de 8,7 [3,8-15,0] %. L'incidence de fibrillation auriculaire variait en fonction du type de chirurgie. Des études prospectives utilisant un monitorage continu par ECG ont fait état d'incidences significativement plus élevées de FA que celles sans monitorage continu (13,9 % vs 1,9 %, respectivement; P < 0,001). Au total, 13 études (25 726 patients) avec un suivi allant jusqu'à 5,4 ans ont rapporté leurs données sur la récurrence de FA après le congé de l'hôpital; seule une étude a utilisé un protocole de monitorage prospectif systématique. Les taux de récurrence allaient de 0 à 37,3 %. CONCLUSION: Les taux d'incidence de nouvelle FA détectés après une chirurgie non cardiaque et la récurrence à long terme de FA varient considérablement. Les différences du degré de monitorage par ECG et le type de chirurgie pourraient expliquer cette variation. ENREGISTREMENT DE L'éTUDE: PROSPERO (CRD42017068055); enregistrée le 1er septembre 2017.

Anomalous circular bulk photovoltaic effect in BiFeO3 thin films with stripe-domain pattern.

Multiferroic bismuth ferrite, BiFeO3, offers a vast landscape to study the interplay between different ferrroic orders. Another aspect which is equally exciting, and yet underutilized, is the possibility of large-scale ordering of domains. Along with symmetry-driven bulk photovoltaic effect, BiFeO3 presents opportunities to conceptualize novel light-based devices. In this work, we investigate the evolution of the bulk photovoltaic effect in BiFeO3 thin films with stripe-domain pattern as the polarization of light is modulated from linear to elliptical to circular. The open-circuit voltages under circularly polarized light exceed ± 25 V. The anomalous character of the effect arises from the contradiction with the analytical assessment involving tensorial analysis. The assessment highlights the need for a domain-specific interaction of light which is further analyzed with spatially-resolved Raman measurements. Appropriate positioning of electrodes allows observation of a switch-like photovoltaic effect, i.e., ON and OFF state, by changing the helicity of circularly polarized light.

High-Sensitivity Estimate of the Incidence of New-Onset Atrial Fibrillation in Critically Ill Patients.

To estimate the incidence of new-onset atrial fibrillation in critically ill patients. DESIGN: Prospective cohort. SETTING: Medical-surgical ICU. SUBJECTS: Consecutive patients without a history of atrial fibrillation but with atrial fibrillation risk factors. INTERVENTIONS: Electrocardiogram patch monitor until discharge from hospital or up to 14 days. MEASUREMENTS AND MAIN RESULTS: A total of 249 participants (median age of 71 yr [interquartile range] 64-78 yr; 35% female) completed the study protocol of which 158 (64%) were admitted to ICU for medical illness, 78 (31%) following noncardiac surgery, and 13 (5%) with trauma. Median Acute Physiology and Chronic Health Evaluation II score was 16 (interquartile range, 12-22). Median duration of patch electrocardiogram monitoring, ICU, and hospital lengths of stay were 6 (interquartile range, 3-12), 4 (interquartile range, 2-8), and 11 days (interquartile range, 5-23 d), respectively.Atrial fibrillation ≥ 30 seconds was detected by the patch in 44 participants (17.7%), and three participants (1.2%) had atrial fibrillation detected clinically after patch removal, resulting in an overall atrial fibrillation incidence of 18.9% (95% CI, 14.2-24.3%).Total duration of atrial fibrillation ranged from 53 seconds to the entire monitoring time. The proportion of participants with ≥1 episode(s) of ≥6 minute, ≥1 hour, ≥12 hour and ≥24 hour duration was 14.8%, 13.2%, 7.0%, and 5.3%, respectively. The clinical team recognized only 70% of atrial fibrillation cases that were detected by the electrocardiogram patch. CONCLUSIONS: Among patients admitted to an ICU, the incidence of new-onset atrial fibrillation is approximately one in five, although approximately one-third of cases are not recognized by the clinical team.

Correlation of chest radiography findings with the severity and progression of COVID-19 pneumonia.

PURPOSE: Aim is to assess the temporal changes and prognostic value of chest radiograph (CXR) in COVID-19 patients. MATERIAL AND METHODS: We performed a retrospective study of confirmed COVID-19 patients presented to the emergency between March 07-17, 2020. Clinical & radiological findings were reviewed. Clinical outcomes were classified into critical & non-critical based on severity. Two independent radiologists graded frontal view CXRs into COVID-19 pneumonia category 1 (CoV-P1) with <4 zones and CoV-P2 with ≥4 zones involvement. Interobserver agreement of CoV-P category for the CXR preceding the clinical outcome was assessed using Kendall's τ coefficient. Association between CXR findings and clinical deterioration was calculated along with temporal changes of CXR findings with disease progression. RESULTS: Sixty-two patients were evaluated for clinical features. 56 of these (total: 325 CXRs) were evaluated for radiological findings. Common patterns were progression from lower to upper zones, peripheral to diffuse involvement, & from ground glass opacities to consolidation. Consolidations starting peripherally were noted in 76%, 93% and 48% with critical outcomes, respectively. The interobserver agreement of the CoV-P category of CXRs in the critical and non-critical outcome groups were good and excellent, respectively (τ coefficient = 0.6 & 1.0). Significant association was observed between CoV-P2 and clinical deterioration into a critical status (χ2 = 27.7, p = 0.0001) with high sensitivity (95%) and specificity (71%) within a median interval time of 2 days (range: 0-4 days). CONCLUSION: Involvement of predominantly 4 or more zones on frontal chest radiograph can be used as predictive prognostic indicator of poorer outcome in COVID-19 patients.

Nanocomposites with Three-Dimensional Architecture and Impact on Photovoltaic Effect.

We demonstrate the synthesis of self-assembled three-dimensional nanocomposite thin films consisting of NiO nanocolumns in an layered Aurivillius phase matrix. The structures were grown on single-crystal SrTiO3 substrates via pulsed laser deposition (PLD) with single ceramic (PbTiO3)x(BiNi2/3Nb1/3O3)1-x targets. The nanocolumns, which are about 10 nm in diameter each, extend over the entire film thickness of up to 225 nm. We reveal the difference in electrical conduction properties of the nanocolumns and the surrounding matrix on the nanoscale via conductive atomic force microscopy. The nanocomposite thin films exhibit improved photovoltaic performance compared to both pure PbTiO3 and homogeneous Aurivillius phase thin films.

Domain and Switching Control of the Bulk Photovoltaic Effect in Epitaxial BiFeO3 Thin Films.

Absence of inversion symmetry is the underlying origin of ferroelectricity, piezoelectricity, and the bulk photovoltaic (BPV) effect, as a result of which they are inextricably linked. However, till now, only the piezoelectric effects (inverse) have been commonly utilized for probing ferroelectric characteristics such as domain arrangements and resultant polarization orientation. The bulk photovoltaic effect, despite sharing same relation with the symmetry as piezoelectricity, has been mostly perceived as an outcome of ferroelectricity and not as a possible analytical method. In this work, we investigate the development of BPV characteristics, i.e. amplitude and angular dependency of short-circuit current, as the ferroelastic domain arrangement is varied by applying electric fields in planar devices of BiFeO3 films. A rather sensitive co-dependency was observed from measurements on sample with ordered and disordered domain arrangements. Analysis of the photovoltaic response manifested in a mathematical model to estimate the proportion of switched and un-switched regions. The results unravel the potential utility of BPV effect to trace the orientation of the polarization vectors (direction and amplitude) in areas much larger than that can be accommodated in probe-based techniques.

Vernakalant for cardioversion of recent-onset atrial fibrillation: a systematic review and meta-analysis.

AIMS: To evaluate the efficacy and safety of vernakalant for the cardioversion of atrial fibrillation (AF). METHODS AND RESULTS: We reviewed the literature for randomized trials that compared vernakalant to another drug or placebo in patients with AF of onset ≤7 days. We used a random-effects model to combine quantitative data and rated the quality of evidence using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation). From 441 total citations in MEDLINE, EMBASE, and CENTRAL (December 2018), we identified nine trials evaluating 1358 participants. Six trials compared vernakalant to placebo, two trials compared vernakalant to ibutilide, and one trial compared vernakalant to amiodarone. We found significant methodological bias in four trials. For conversion within 90 min, vernakalant was superior to placebo [50% conversion, risk ratio (RR) 5.15; 95% confidence interval (CI); 2.24-11.84, I2 = 91%], whereas we found no significant difference in conversion when vernakalant was compared with an active drug (56% vs. 24% conversion, RR 2.40; 95% CI 0.76-7.58, I2 = 94). Sinus rhythm was maintained at 24 h in 85% (95% CI 80-88%) of patients who converted acutely with vernakalant. Overall, we judged the quality of evidence for efficacy to be low based on inconsistency and suspected publication bias. There was no significant difference in the risk of significant adverse events between vernakalant and comparator (RR 0.95; 95% CI 0.70-1.28, I2 = 0, moderate quality evidence). Vernakalant is safe and effective for rapid and durable restoration of sinus rhythm in patients with recent-onset AF. CONCLUSION: Vernakalant should be a first line option for the pharmacological cardioversion of patients with haemodynamically stable recent-onset AF without severe structural heart disease.

Comparison of Two Different Non-Radiographic Mixed Dentition Analysis

Objective: To evaluate the applicability of two different non-radiographic mixed dentition analysis in school going children of Aligarh district, India. Material and Methods: Mesiodistal dimension was measured on the dental casts of 120 school going children with electronic digital vernier caliper. The following inclusion criteria were adopted: presence of all fully erupted permanent teeth; no congenital craniofacial anomalies; no previous history of orthodontic treatment; and presence of intact dentition with no proximal caries, restoration, or age related attrition. Predicted values of canines and premolars were obtained from Moyer's at 75th percentile and Tanaka and Johnston mixed dentition analysis. Descriptive statistics were used to calculate the mean and standard deviation. Paired observations were compared by t­test. The level of significance was at p<0.001. Results: The mean difference between the predicted and the actual value of canines and premolars using Moyer's probability table at 75th percentile and Tanaka and Johnston regression equation were statistically significant. No significant differences were found between Moyer's analysis 75th percentile and Tanaka and Johnston mixed dentition analysis in both arch and sexes. Conclusion: These two non-radiographic mixed dentition analysis overestimated the mesiodistal width of canines and premolars.

Electromagnetic Functionalization of Wide-Bandgap Dielectric Oxides by Boron Interstitial Doping.

A surge in interest of oxide-based materials is testimony for their potential utility in a wide array of device applications and offers a fascinating landscape for tuning the functional properties through a variety of physical and chemical parameters. In particular, selective electronic/defect doping has been demonstrated to be vital in tailoring novel functionalities, not existing in the bulk host oxides. Here, an extraordinary interstitial doping effect is demonstrated centered around a light element, boron (B). The host matrix is a novel composite system, made from discrete bulk LaAlO3 :LaBO3 compounds. The findings show a spontaneous ordering of the interstitial B cations within the host LaAlO3 lattices, and subsequent spin-polarized charge injection into the neighboring cations. This leads to a series of remarkable cation-dominated electrical switching and high-temperature ferromagnetism. Hence, the induced interstitial doping serves to transform a nonmagnetic insulating bulk oxide into a ferromagnetic ionic-electronic conductor. This unique interstitial B doping effect upon its control is proposed to be as a general route for extracting/modifying multifunctional properties in bulk oxides utilized in energy and spin-based applications.

Comparative evaluation and applicability of three different regression equation-based mixed dentition analysis in Northern Uttar Pradesh population.

AIMS: This study aims to examine the accuracy and comparative correlation of three regression equation-based mixed dentition analysis in children of Moradabad city, North Uttar Pradesh. SETTINGS AND DESIGN: Tanaka-Johnston, Bernabe-Flores-Mir, and Ling-Wong regression equations were developed from a sample of North European, Peru, and Southern Chinese children population, respectively. Hence, it becomes questionable when applied to children of Moradabad city situated in North Uttar Pradesh, India. SUBJECTS AND METHODS: The study was conducted on a sample of 100 school going children, age range is 11-14 years with complete permanent teeth except third molars. The mesiodistal crown dimensions of all erupted incisors, canines, premolars, and molars were measured with digital calipers with a calibration accuracy of 0.01 mm. The actual tooth measurements were then compared with predicted values using Tanaka-Johnston, Bernabe-Flores-Mir, and Ling-Wong regression equations, respectively using paired t-test. RESULTS: The mean difference between the actual and estimated values of canines and premolars using Tanaka-Johnston, Bernabe-Flores-Mir, and Ling-Wong were clinically and statistically significant (P< 0.001). CONCLUSIONS: Mesiodistal dimensions of male samples are larger than female samples. All the three regression equations are not accurately applicable to this population.

Antimicrobial Efficacy of Chemical and Herbal Agents against Streptococcus mutans: An in vitro study

Objective: To compare and evaluate antimicrobial efficacy of chlorhexidine gluconate and fennel seeds against Streptococcus mutans. Material and Methods: Three agar petri dishes for Streptococcus mutans were prepared. The methanolic extract of fennel seed and 0.2% chlorhexidine were inoculated on the each petri dish and incubated at 37ºC for 24 hours. Zone of growth inhibition for each extract was measured in millimeters using antibiotic inhibiting zone measuring scale. Data was analyzed using SPSS statistical software. The comparison of inhibition zone against S. mutans using CHX and fennel seed extract was done using Mann-Whitney and Wilcoxon tests. All statistical analyses were set at a significance level of p<0.05. Results: The mean of zone of inhibition of S. mutans after inoculation with 0.2% chlorhexidine and fennel seed extract are 21.44 ±1.46, 15.34 ±0.74 respectively. There was statistically significant difference in the mean of inhibition zone between 0.2% chlorhexidine and fennel seed against S. mutans (p=0.047). Conclusion: Chlorhexidine and fennel seed are effective in inhibiting the growth of cariogenic bacteria. Therefore, both herbal and chemical agents can be effectively used to reduce pathogenic oral microflora.

Enhancement of Local Photovoltaic Current at Ferroelectric Domain Walls in BiFeO3.

Domain walls, which are intrinsically two dimensional nano-objects exhibiting nontrivial electronic and magnetic behaviours, have been proven to play a crucial role in photovoltaic properties of ferroelectrics. Despite this recognition, the electronic properties of domain walls under illumination until now have been accessible only to macroscopic studies and their effects upon the conduction of photovoltaic current still remain elusive. The lack of understanding hinders the developing of nanoscale devices based on ferroelectric domain walls. Here, we directly characterize the local photovoltaic and photoconductive properties of 71° domain walls on BiFeO3 thin films with a nanoscale resolution. Local photovoltaic current, proven to be driven by the bulk photovoltaic effect, has been probed over the whole illuminated surface by using a specially designed photoelectric atomic force microscopy and found to be significantly enhanced at domain walls. Additionally, spatially resolved photoconductive current distribution reveals a higher density of excited carriers at domain walls in comparison with domains. Our measurements demonstrate that domain wall enhanced photovoltaic current originates from its high conduction rather than the internal electric field. This photoconduction facilitated local photovoltaic current is likely to be a universal property of topological defects in ferroelectric semiconductors.

Evaluation of Three Different Regression Equations Based Mixed Dentition Analysis in Children of Moradabad City, India

Objective: To assess the accuracy and applicability of three regression equations based mixed dentition analysis in children of Moradabad city, India. Material and Methods: Actual mesiodistal width of maxillary and madibular incisors, canines and premolars of 100 children (50 male and 50 female) aged 11-14 years were measured on dental cast with electronic digital vernier caliper. The analysis of Tanaka- Johnston, Ling-Wong and Jaroontham-Godfrey regression equations were tested on the dental casts. All analyses were performed on SPSS software. Data were summarized as Mean ± standard deviation (SD) paired observations were compared by paired t-test (two-tailed test) while independent groups were compared by independent Student's t-test. The level of significance was at P < 0.001. Results: The analysis of Tanaka-Johnston, Ling-Wong, Jaroontham-Godfrey regression equations tended to overestimate the mesiodistal width of the canines and premolars with the actual measured values. Conclusion: All the three regression equations based mixed dentition overestimated the mesiodistal width of canines and premolars in Moradabad population.

Surface passivation of semiconducting oxides by self-assembled nanoparticles.

Physiochemical interactions which occur at the surfaces of oxide materials can significantly impair their performance in many device applications. As a result, surface passivation of oxide materials has been attempted via several deposition methods and with a number of different inert materials. Here, we demonstrate a novel approach to passivate the surface of a versatile semiconducting oxide, zinc oxide (ZnO), evoking a self-assembly methodology. This is achieved via thermodynamic phase transformation, to passivate the surface of ZnO thin films with BeO nanoparticles. Our unique approach involves the use of Be(x)Zn(1-x)O (BZO) alloy as a starting material that ultimately yields the required coverage of secondary phase BeO nanoparticles, and prevents thermally-induced lattice dissociation and defect-mediated chemisorption, which are undesirable features observed at the surface of undoped ZnO. This approach to surface passivation will allow the use of semiconducting oxides in a variety of different electronic applications, while maintaining the inherent properties of the materials.

Persistent photoconductivity in strained epitaxial BiFeO3 thin films.

A drastic change in the conductivity of strained BiFeO3 (BFO) films is observed after illuminating them with above-band gap light. This has been termed as persistent photoconductivity. The enhanced conductivity decays exponentially with time. A trapping character of the sub-band levels and their subsequent gradual emptying is proposed as a possible mechanism.

Feeding tube placement: errors and complications.

Feeding tube placement for enteral nutrition (EN) support is widely used in both critically ill and stable chronically ill patients who are unable to meet their nutrition needs orally. Nasal or oral feeding tubes can be performed blindly at the bedside or with fluoroscopic or endoscopic guidance into the stomach or small bowel. Percutaneous feeding tubes are used when EN support is required for longer periods (>4-6 weeks) and are most commonly placed endoscopically or radiographically. Although generally safe and effective, there is a wide spectrum of known complications associated with feeding tube placement. Errors made at the time of feeding tube placement can result in a number of these procedural and postprocedural complications. In many cases, a single error at the time of placement can result in numerous complications. A thorough knowledge of these errors and avoiding them in practice will decrease iatrogenic complications in a vulnerable population. In addition, early recognition and management of complications will further minimize morbidity and even mortality in enteral feeding tube placement. This article reviews the common errors leading to complications of enteral feeding tube placement and their prevention and management.