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Currently, developing materials with high power capability is crucial to the rapid deployment of electric vehicles. The Li4Ti5O12 (LTO) anode material with zero strain rate upon lithium insertion and extraction. The successful implementation of this anode material depends on strategies to overcome the low electronic and ionic conductivity. In this study, Li4Ti5O12 was synthesized using solid‐state approach in which different phases (anatase and rutile) of TiO2 as precursors were used. X‐ray photoelectron spectroscopy (XPS) and Raman analysis confirmed the formation of oxygen vacancies with the existence of Ti3+ ions, which is believed to greatly enhance the electronic conductivity of Li4Ti5O12. The electrochemical performance revealed that the rutile TiO2 precursor concentration significantly affects the resultant Li4Ti5O12 capacity and power capability. The Li4Ti5O12 synthesized using 80% anatase and 20% rutile TiO2 (N2‐LTO) exhibits a specific capacity of 169, 145, 140, 133, 122, 101, and 84 mAh g−1 at 1C, 3C, 5C, 7C, 10C, 20C, and 30C. In addition, LFP||N2‐LTO pouch‐cell was fabricated which showed promising results with 95% capacity retention after 1000 cycles at 1C rate. The oxygen vacancies created due to the presence of Ti3+/Ti4+ mixed valances and reduced particle size for faster lithium‐ion diffusion significantly enhanced the overall electrochemical performance. [ABSTRACT FROM AUTHOR]

In this paper, an attempt was made to synthesize LaNiO3, CeNiO3, and BaNiO3, and Ce3+ and Ba2+ co-substituted LaNiO3. These samples were further subjected to various material characterization techniques in order to evaluate their physio-chemical properties. Scanning electron microscope (SEM) images showed large chunks of aggregated nanoparticles with minute voids. The EDX-derived atomic composition deviated from the nominal composition suggesting the occurrence of multiple phases. In addition, transmission electron microscope (TEM) images revealed that the samples exhibit uneven spherical shape with a high degree of aggregation. The Fourier transformed-infrared (FT-IR) spectra of the synthesized samples show vibrations of the BO6 octahedral indicating the presence of Ni–O bonds. In addition, metal-carboxyl vibrations were identified from the peaks at 1400 and 860 cm−1. Optical diffuse reflectance spectra (DRS) showed certain peaks originating from the O2− (2p) → Ni2+ (3d) charge transfer. The X-ray powder diffraction (XRPD) analysis revealed the existence of multiple phases for the samples CeNiO3, BaNiO3, and La(Ce, Ba)NiO3. Moreover, La(Ce, Ba)NiO3 contained four phases showing that the co-substitution of Ba2+ and Ce3+ into LaNiO3 may require more sophisticated methodologies. The sample BaNiO3 showed maximum weight loss, due to the existence of carbonate phase. The dielectric properties decreased with increasing frequency, while the ac electrical conductivity enhanced with increasing frequencies obeying the Maxwell–Wagner two-layer model in accordance with Koop's phenomenological theory. [ABSTRACT FROM AUTHOR]

Perovskite-type oxides La1-xCaxFeO3 (x = 0.0–1.0) were synthesized using combustion technique. The samples have been investigated using scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy (DRS), X-ray powder diffraction (XRPD) using Rietveld refinement, thermogravimetric analysis (TGA) and dielectric spectroscopy. The SEM images showed spherical-shaped agglomerates having a non-uniform distribution of size. The EDX results suggested that the experimental chemical composition was in good accordance with the nominal values. FT-IR revealed multiple peaks in the range of 580–510 cm−1 due to asymmetric stretching of the octahedron. The reflectance spectra showed characteristic d → d transitions arising from the Fe 3d and the highest optical band gap energy ( E g ) of 2.57 eV was exhibited by LaFeO3, while the lowest E g (1.41 eV) was shown by La1-xCaxFeO3 with x = 0.6. The results suggest that these samples are suitable for photocatalytic applications. From phase evaluation of the diffraction patterns, it was found that five distinct phases exist in the series. A phase transformation from orthorhombic ( Pnma ) to cubic ( P m 3 ¯ m ) was found when x was increased from 0.4 to 0.6. TGA showed that LaFeO3 was the most stable with a residual mass of ~ 97 wt% at 900 ∘ C compared to CaFeO3 (~ 70 wt% at 900 ∘ C ). The evaluation of frequency-dependent (20 Hz–20 MHz) dielectric properties agreed with the Maxwell–Wagner two-layer model. After Ca2+ substitution, tan δ at 20 Hz significantly reduced from ~ 103 for x = 0 to ~ 100 for x = 1.0. The high polarization observed was due to e− hopping between Fe2+ ↔ Fe3+. The electrical models of the samples show non-Debye type relaxation behavior, while the ac conductivity enhanced with increasing frequency which was in accordance with Koop's phenomenological theory. [ABSTRACT FROM AUTHOR]

Epoxy composites were prepared by doping nano Zirconia Toughened Alumina (ZTA) which were synthesized by solution combustion method into epoxy resin and hardener. Initially ZTA nanopowder was characterized to check its purity, morphology and to confirm its metal-oxide bonding using XRD, SEM and FTIR respectively. The thermal properties such as TGA and DTG were also analysed. The polymer composites were obtained by uniformly dispersing ZTA nanopowder into epoxy using an ultrasonicator. Polymer composites of various concentrations viz, 0.5, 1, 1.5, 2 and 2.5 wt% were synthesized, all concentrations were prepared on weight basis. All the polymer composites were tested for compression properties, flexural properties and tensile properties. Best results for all the mechanical properties were obtained for epoxy with 1.5 wt% ZTA composites. Electrical properties such as breakdown voltage and breakdown strength were analysed and outstanding results were observed for epoxy with 2.5 wt% ZTA composite. [ABSTRACT FROM AUTHOR]

Objective: Insufflation of the amniotic cavity with carbon dioxide (CO2) is used clinically to improve visibility during complex fetoscopic surgery. Insufflation with heated, humidified CO2 has recently been shown to reduce fetal hypercapnia and acidosis in sheep, compared with use of cold and dry CO2, but the underlying mechanisms are unclear. The aim of this study was to investigate whether differences in placental CO2 and oxygen (O2) exchange during insufflation with heated and humidified vs cold and dry CO2 could explain these findings. Methods: Thirteen fetal lambs at 105 days of gestation (term, 146 days) were exteriorized partially, via a midline laparotomy and hysterotomy, and instrumented with an umbilical artery catheter, an umbilical vein catheter and a common umbilical vein flow probe. Arterial and venous catheters and flow probes were also inserted into the maternal uterine circulation. Six ewes were insufflated with cold, dry CO2 (22°C; 0–5% humidity) and seven with heated, humidified CO2 (40°C; 95–100% humidity) at 15 mmHg for 180 min. Blood‐flow recordings and paired arterial and venous blood gases were sampled from uterine and umbilical vessels. Rates of placental CO2 and O2 exchange were calculated. Results: After 180 min of insufflation, fetal survival was 33% (2/6) using cold, dry CO2 and 71% (5/7) using heated, humidified CO2. By 120 min, fetuses insufflated with heated, humidified CO2 had lower arterial CO2 levels and higher arterial pH compared to those insufflated with cold, dry gas. Insufflation decreased significantly placental gas exchange in both groups, as measured by rates of both (i) fetal CO2 clearance and O2 uptake and (ii) maternal O2 delivery and CO2 uptake from the fetal compartment. Conclusions: Lower arterial CO2 and higher pH levels in fetuses insufflated with heated and humidified, compared to cold and dry, CO2 could not be explained by differences in placental gas exchange. Instead, heated and humidified insufflation appeared to reduce fetal CO2 absorption from the uterus, supporting its use in preference to cold, dry CO2. © 2019 International Society of Ultrasound in Obstetrics and Gynecology [ABSTRACT FROM AUTHOR]

Understanding why deep neural networks and machine learning algorithms act as they do is a difficult endeavor. Neuroscientists are faced with similar problems. One way biologists address this issue is by closely observing behavior while recording neurons or manipulating brain circuits. This has been called neuroethology. In a similar way, neurorobotics can be used to explain how neural network activity leads to behavior. In real world settings, neurorobots have been shown to perform behaviors analogous to animals. Moreover, a neuroroboticist has total control over the network, and by analyzing different neural groups or studying the effect of network perturbations (e.g., simulated lesions), they may be able to explain how the robot's behavior arises from artificial brain activity. In this paper, we review neurorobot experiments by focusing on how the robot's behavior leads to a qualitative and quantitative explanation of neural activity, and vice versa, that is, how neural activity leads to behavior. We suggest that using neurorobots as a form of computational neuroethology can be a powerful methodology for understanding neuroscience, as well as for artificial intelligence and machine learning. [ABSTRACT FROM AUTHOR]

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Objective: Lung hypoplasia associated with congenital diaphragmatic hernia (CDH) results in respiratory insufficiency and pulmonary hypertension after birth. We have investigated whether aerating the lung before removing placental support (physiologically based cord clamping (PBCC)), improves the cardiopulmonary transition in lambs with a CDH.Methods: At ≈138 days of gestational age, 17 lambs with surgically induced left-sided diaphragmatic hernia (≈d80) were delivered via caesarean section. The umbilical cord was clamped either immediately prior to ventilation onset (immediate cord clamping (ICC); n=6) or after achieving a target tidal volume of 4 mL/kg, with a maximum delay of 10 min (PBCC; n=11). Lambs were ventilated for 120 min and physiological changes recorded.Results: Pulmonary blood flow (PBF) increased following ventilation onset in both groups, but was 19-fold greater in PBCC compared with ICC lambs at cord clamping (19±6.3 vs 1.0±0.5 mL/min/kg, p<0.001). Cerebral tissue oxygenation was higher in PBCC than ICC lambs during the first 10 min after cord clamping (59%±4% vs 30%±5%, p<0.001). PBF was threefold higher (23±4 vs 8±2 mL/min/kg, p=0.01) and pulmonary vascular resistance (PVR) was threefold lower (0.6±0.1 vs 2.2±0.6 mm Hg/(mL/min), p<0.001) in PBCC lambs compared with ICC lambs at 120 min after ventilation onset.Conclusions: Compared with ICC, PBCC prevented the severe asphyxia immediately after birth and resulted in a higher PBF due to a lower PVR, which persisted for at least 120 min after birth in CDH lambs. [ABSTRACT FROM AUTHOR]

Objective: Infants with a congenital diaphragmatic hernia (CDH) are at high risk of developing pulmonary hypertension after birth, but little is known of their physiological transition at birth. We aimed to characterise the changes in cardiopulmonary physiology during the neonatal transition in an ovine model of CDH.Methods: A diaphragmatic hernia (DH) was surgically created at 80 days of gestational age (dGA) in 10 fetuses, whereas controls underwent sham surgery (n=6). At 138 dGA, lambs were delivered via caesarean section and ventilated for 2 hours. Physiological and ventilation parameters were continuously recorded, and arterial blood gas values were measured.Results: DH lambs had lower wet lung-to-body-weight ratio (0.016±0.002vs0.033±0.004), reduced dynamic lung compliance (0.4±0.1mL/cmH2O vs1.2±0.1 mL/cmH2O) and reduced arterial pH (7.11±0.05vs7.26±0.05), compared with controls. While measured pulmonary blood flow (PBF) was lower in DH lambs, after correction for lung weight, PBF was not different between groups (4.05±0.60mL/min/gvs4.29±0.57 mL/min/g). Cerebral tissue oxygen saturation was lower in DH compared with control lambs (55.7±3.5vs67.7%±3.9%).Conclusions: Immediately after birth, DH lambs have small, non-compliant lungs, respiratory acidosis and poor cerebral oxygenation that reflects the clinical phenotype of human CDH. PBF (indexed to lung weight) was similar in DH and control lambs, suggesting that the reduction in PBF associated with CDH is proportional to the degree of lung hypoplasia during the neonatal cardiopulmonary transition. [ABSTRACT FROM AUTHOR]

Objective: Fetoscopic endoluminal tracheal occlusion (FETO) aims to reverse pulmonary hypoplasia associated with congenital diaphragmatic hernia (CDH) and mitigate the associated respiratory insufficiency and pulmonary hypertension after birth. We aimed to determine whether FETO improves the cardiopulmonary transition at birth in an ovine model of CDH.Methods: In 12 ovine fetuses with surgically induced diaphragmatic hernia (DH; 80 dGA), an endotracheal balloon was placed tracheoscopically at ≈110 dGA and removed at ≈131 dGA (DH+FETO), while 10 were left untreated (DH). At ≈138 dGA, all lambs (survival at delivery: 67% [DH+FETO], 70% [DH]) were delivered via caesarean section and ventilated for 2 hours. Physiological and ventilation parameters were continuously recorded, and arterial blood-gas values were measured.Results: Compared with DH, DH+FETO lambs had increased wet lung-to-body-weight ratio (0.031±0.004 vs 0.016±0.002) and dynamic lung compliance (0.7±0.1 vs 0.4±0.1 mL/cmH2O). Pulmonary vascular resistance was lower in DH+FETO lambs (0.44±0.11 vs 1.06±0.17 mm Hg/[mL/min]). However, after correction for lung weight, pulmonary blood flow was not significantly different between the groups (4.19±0.57 vs 4.05±0.60 mL/min/g). Alveolar-arterial difference in oxygen tension was not significantly different between DH+FETO and DH (402±41mm Hg vs 401±45 mm Hg).Conclusions: FETO accelerated lung growth in fetuses with CDH and improved neonatal respiratory function during the cardiopulmonary transition at birth. However, despite improved lung compliance and reduced pulmonary vascular resistance, there were less pronounced benefits for gas exchange during the first 2 hours of life. [ABSTRACT FROM AUTHOR]

Objectives: Infants with congenital diaphragmatic hernia (CDH) are predisposed to pulmonary hypertension after birth, owing to lung hypoplasia that impairs fetal pulmonary vascular development. Antenatal sildenafil treatment attenuates abnormal pulmonary vascular and alveolar development in rabbit and rodent CDH models, but whether this translates to functional improvements after birth remains unknown. We aimed to evaluate the effect of antenatal sildenafil on neonatal pulmonary hemodynamics and lung function in lambs with diaphragmatic hernia (DH).Methods: DH was surgically induced at approximately 80 days' gestation in 16 lamb fetuses (term in lambs is approximately 147 days). From 105 days' gestation, ewes received either sildenafil (0.21 mg/kg/h intravenously) or saline infusion until delivery (n = 8 fetuses in each group). At approximately 138 days' gestation, all lambs were instrumented and then delivered via Cesarean section. The lambs were ventilated for 120 min with continuous recording of physiological (pulmonary and carotid artery blood flow and pressure; cerebral oxygenation) and ventilatory parameters, and regular assessment of arterial blood gas tensions. Only lambs that survived until delivery and with a confirmed diaphragmatic defect at postmortem examination were included in the analysis; these comprised six DH-sildenafil lambs and six DH-saline control lambs.Results: Lung-to-body-weight ratio (0.016 ± 0.001 vs 0.013 ± 0.001; P = 0.06) and dynamic lung compliance (0.8 ± 0.2 vs 0.7 ± 0.2 mL/cmH2 O; P = 0.72) were similar in DH-sildenafil lambs and controls. Pulmonary vascular resistance decreased following lung aeration to a greater degree in DH-sildenafil lambs, and was 4-fold lower by 120 min after cord clamping than in controls (0.6 ± 0.1 vs 2.2 ± 0.6 mmHg/(mL/min); P = 0.002). Pulmonary arterial pressure was also lower (46 ± 2 vs 59 ± 2 mmHg; P = 0.048) and pulmonary blood flow higher (25 ± 3 vs 8 ± 2 mL/min/kg; P = 0.02) in DH-sildenafil than in DH-saline lambs at 120 min. Throughout the 120-min ventilation period, the partial pressure of arterial carbon dioxide tended to be lower in DH-sildenafil lambs than in controls (63 ± 8 vs 87 ± 8 mmHg; P = 0.057), and there was no significant difference in partial pressure of arterial oxygen between the two groups.Conclusions: Sustained maternal antenatal sildenafil infusion reduced pulmonary arterial pressure and increased pulmonary blood flow in DH lambs for the first 120 min after birth. These findings of improved pulmonary vascular function are consistent with improved pulmonary vascular structure seen in two previous animal models. The data support the rationale for a clinical trial investigating the effect of antenatal sildenafil in reducing the risk of neonatal pulmonary hypertension in infants with CDH. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Newborns with lung hypoplasia (LH) commonly have limited respiratory function and often require ventilatory assistance after birth. We aimed to characterize the cardiorespiratory transition and respiratory function in newborn lambs with LH. LH was induced by draining fetal lung liquid in utero [110-133 days (d), term = 147d, n = 6]. At ~133d gestation, LH and Control lambs (n = 6) were instrumented and ventilated for 3 h to monitor blood-gas status, oxygenation, ventilator requirements, and hemodynamics during the transition from fetal to newborn life. Lambs with LH had significantly reduced relative wet and dry lung weights indicating hypoplastic lungs compared with Control lambs. LH lambs experienced persistent hypercapnia and acidosis during the ventilation period, had lower lung compliance, and had higher alveolar-arterial differences in oxygen and oxygenation index compared with Control lambs. As a result, LH lambs required greater respiratory support and more supplemental oxygen. Following delivery, LH lambs experienced periods of significantly lower pulmonary artery blood flow and higher carotid artery blood flow in association with the lower oxygenation levels. The detrimental effects of LH can be attributed to a reduction in lung size and poorer gas exchange capabilities. This study has provided greater understanding of the effect of LH itself on the physiology underpinning the transition from fetal to newborn life. Advances in this area is the key to identifying improved or novel management strategies for babies with LH starting in the delivery room, to favorably alter the fetal-to-newborn transition toward improved outcomes and reduced lifelong morbidity. [ABSTRACT FROM AUTHOR]

Objective: Partial amniotic carbon dioxide (CO2 ) insufflation (PACI) is used to improve visualization and facilitate complex fetoscopic surgery. However, there are concerns about fetal hypercapnic acidosis and postoperative fetal membrane inflammation. We assessed whether using heated and humidified, rather than cold and dry, CO2 might reduce the impact of PACI on the fetus and fetal membranes in sheep.Methods: Twelve fetal lambs of 105 days' gestational age (term = 145 days) were exteriorized partially, via a midline laparotomy and hysterotomy, and arterial catheters and flow probes were inserted surgically. The 10 surviving fetuses were returned to the uterus, which was then closed and insufflated with cold, dry (22 °C at 0-5% humidity, n = 5) or heated, humidified (40 °C at 100% humidity, n = 5) CO2 at 15 mmHg for 180 min. Fetal membranes were collected immediately after insufflation for histological analysis. Physiological data and membrane leukocyte counts, suggestive of membrane inflammation, were compared between the two groups.Results: After 180 min of insufflation, fetal survival was 0% in the group which underwent PACI with cold, dry CO2 , and 60% (n = 3) in the group which received heated, humidified gas. While all insufflated fetuses became progressively hypercapnic (PaCO2  > 68 mmHg), this was considerably less pronounced in those in which heated, humidified gas was used: after 120 min of insufflation, compared with those receiving cold, dry gas (n = 3), fetuses undergoing heated, humidified PACI (n = 5) had lower arterial partial pressure of CO2 (mean ± standard error of the mean, 82.7 ± 9.1 mmHg for heated, humidified CO2 vs 170.5 ± 28.5 for cold, dry CO2 during PACI, P < 0.01), lower lactate levels (1.4 ± 0.4 vs 8.5 ± 0.9 mmol/L, P < 0.01) and higher pH (pH, 7.10 ± 0.04 vs 6.75 ± 0.04, P < 0.01). There was also a non-significant trend for fetal carotid artery pressure to be higher following PACI with heated, humidified compared with cold, dry CO2 (30.5 ± 1.3 vs 8.7 ± 5.5 mmHg, P = 0.22). Additionally, the median (interquartile range) number of leukocytes in the chorion was significantly lower in the group undergoing PACI with heated, humidified CO2 compared with the group receiving cold, dry CO2 (0.7 × 10-5 (0.5 × 10-5 ) vs 3.2 × 10-5 (1.8 × 10-5 ) cells per square micron, P = 0.02).Conclusions: PACI with cold, dry CO2 causes hypercapnia, acidosis, hypotension and fetal membrane inflammation in fetal sheep, raising potential concerns for its use in humans. It seems that using heated, humidified CO2 for insufflation partially mitigates these effects and this may be a suitable alternative for reducing the risk of fetal acid-base disturbances during, and fetal membrane inflammation following, complex fetoscopic surgery. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Distributed denial of service (DDoS) attack is a coordinated attack, generally performed on a massive scale on the availability of services of a target system or network resources. Owing to the continuous evolution of new attacks and ever-increasing number of vulnerable hosts on the Internet, many DDoS attack detection or prevention mechanisms have been proposed. In this paper, we present a comprehensive survey of DDoS attacks, detection methods and tools used in wired networks. The paper also highlights open issues, research challenges and possible solutions in this area. [ABSTRACT FROM AUTHOR]