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Caesarean section delivery (CD) is the most common surgical operation performed in the world. Since first described 400 years ago, surgical rates continue to rise globally. Caesarean rates are now reported from South American countries of over 50% and rates of over 32% are currently being reported from the United States, China, England and Scotland. Surgical complications can occur at the time of operation and there are major implications for future pregnancies, including increased rates of placenta previa/accreta, stillbirth and preterm labour. This Element discusses many aspects of CD, including the Robson 10 group classification system, which classifies populations by characteristics such as parity, presentation of the fetus and the history of previous births, an evidencebased approach to surgical techniques, recommendations of the major guidelines and recommendations concerning trial of labour after previous caesarean.
Redweed is a tropical, erect branched herb, and one of the predominant broadleaf weeds affecting upland crops in the Onattukara Sandy Plains of Kerala, India. Experiments were conducted in a screenhouse in Thiruvananthapuram, Kerala, India, to determine the effects of seed burial depth and seed scarification on emergence indices and growth attributes of redweed. Scarification stimulated emergence and resulted in greater values for emergence indices and seedling parameters. The seedling emergence of redweed was influenced by seed burial depth. Shallow seed burial (2 cm) of scarified and non-scarified seeds resulted in greater seedling length (70 cm and 58 cm, respectively), seedling biomass (0.72 g and 0.48 g, respectively), emergence percentage (60% and 32%, respectively), and greater values for other emergence indices. As the depth of seed burial increased from 2 cm, emergence and seedling biomass decreased, exhibiting lower values for the emergence indices. Correlation and regression studies revealed that seed burial depth of scarified and non-scarified seeds greater than 2 cm had a negative effect on seedling emergence and biomass of redweed. Weed biology studies indicated that redweed displayed notable consistency in its phenological traits, regardless of the location where the seeds were collected, as little ecotype variability was observed. Emergence occurred in 6 d, 50% flowering in 44 d, capsule formation in 56 d, and maturity in 76 d. On average, a single plant produced 277 seeds and had a 100-seed weight of 0.31 g. A stale seedbed with shallow tillage or deep plowing to a depth of 10 cm before sowing can be adopted to reduce the infestation of redweed.
KCNT1 mutations are associated with childhood epilepsy, developmental delay, and vascular malformations. We report a child with a likely pathogenic KCNT1 mutation (c.1885A>C, p.Lys629Glu) with recurrent pulmonary haemorrhage due to aortopulmonary collaterals successfully managed with coil embolisation followed by right upper lobectomy.
Cardiovascular disease (CVD) is largely preventable, and the leading cause of death for men and women. Though women have increased life expectancy compared to men, there are marked sex disparities in prevalence and risk of CVD-associated mortality and dementia. Yet, the basis for these and female-male differences is not completely understood. It is increasingly recognized that heart and brain health represent a lifetime of exposures to shared risk factors (including obesity, hyperlipidemia, diabetes, and hypertension) that compromise cerebrovascular health. We describe the process and resources for establishing a new research Center for Women’s Cardiovascular and Brain Health at the University of California, Davis as a model for: (1) use of the cy pres principle for funding science to improve health; (2) transdisciplinary collaboration to leapfrog progress in a convergence science approach that acknowledges and addresses social determinants of health; and (3) training the next generation of diverse researchers. This may serve as a blueprint for future Centers in academic health institutions, as the cy pres mechanism for funding research is a unique mechanism to leverage residual legal settlement funds to catalyze the pace of scientific discovery, maximize innovation, and promote health equity in addressing society’s most vexing health problems.
In the present paper, filamentous structure formation, associated turbulent spectrum, and density cavity formation phenomena have been investigated for low-β plasma applicable to the auroral region. A set of dimensionless equations governing the dynamics of three dimensionally propagating inertial Alfvén wave (3D-IAW) and perpendicularly propagating magnetosonic wave (PMSW) has been developed. Ponderomotive force due to 3D-IAW has been included in the dynamics of the PMSW. Numerical simulation has been performed to study the nonlinear coupling of these two waves. From the obtained results, we found that the field intensity localization takes place which may further lead to the additional dissipation/turbulence process for particle heating and acceleration in space plasma. The associated turbulent spectrum is obtained with scaling nearly k−4.28 at smaller scales (in the dissipation range). Relevance of the obtained results with the observations reported by various spacecrafts such as Hawkeye and Heos 2 has been discussed. Also, density fluctuations (depletion) of ∼0.10 n0 are calculated, which are consistent with the FAST spacecraft observation reported.
The eruption of Toba ca. 75 ka was the largest volcanic eruptive event during the Quaternary, and evidence for this eruption is widespread in terrestrial sediment sequences in South Asia as primary and reworked distal ash deposits. Youngest Toba Tuff horizons (YTT) have been widely employed as isochrons to understand and link regional sediment sequences and the evidence for environmental and cultural change in the archaeological records preserved within them. We identify the YTT deposits at Retlapalle, Andhra Pradesh, India, and present the optical ages of the K-feldspar grains recovered from sediments immediately underlying and overlying the tephra horizon. We combine these results with particle size and magnetic susceptibility analyses to establish the depositional conditions of YTT, which indicate that accumulation and reworking ceased by ca. 64 ka. We explore the role of YTT deposits as an isochron for examining the effect of the 75 ka Toba super-eruption, highlighting the need for an independent chronological assessment of YTT before using it as a Late Pleistocene chronological marker in reconstructing South Asian paleo-landscapes and hominin adaptations. Further, our findings support the regional continuity of human occupations within South Asia, spanning the eruption of Toba and the enduring utility of Middle Paleolithic tools.
Dichanthium annulatum is one of the dominant grasses of India, North Africa, Southeast Asia, China, Australia, Fiji, New Guinea, Cuba, Haiti and Puerto Rico. This drought-tolerant grass is an excellent fodder in mixed pastures. Developing varieties with improved quality and tolerance to various abiotic stresses is hampered due to its apomictic nature. Germplasm collection, characterization, genetic diversity analysis and core subset development followed by selection for desirable traits seems to be the most plausible breeding tool for developing new cultivars. In the present study, 498 genotypes collected from different agro-ecological zones in India were included. Genotypes were characterized for various metric and non-numeric traits; and the nutritional parameters. Agglomerative clustering analysis, using the Euclidean distance method, showed 14 distinct clusters. High variability was recorded for green forage yield, quantitative traits and nutritive quality parameters. A core subset of 50 accessions was identified, which captured most of the morphological and nutritional variability present in the total germplasm. Clustering of genotypes was observed to be related to the climatic conditions of the place of collection. High genetic variability observed for various morphological traits as well as forage yield indicated that these genotypes or subset of genotypes can be evaluated in different abiotic stress conditions such as salt, light and moisture stress for the identification of suitable varieties for the respective areas. Variability was attributed to inter-generic, inter-specific crossing together with the occasional presence of sexual plants in nature.
Weeds are a major biotic constraint to the production of crops. Studies on the critical period of weed control (CPWC) consider the yield loss due to the presence of all weeds present in the crop cycle. The CPWC is the time interval between the critical timing of weed removal (CTWR) and the critical weed-free period (CWFP), and the weed presence before and after the extremes of CTWR and CWFP may not significantly reduce crop yield. The crop yield is taken into consideration and weed density or biomass of individual weeds (annual or perennial) is not so important while calculating the CPWC. Only weed density or biomass is considered for calculating weed control efficiency of a particular management practice for which the weed seed bank is also a criterion. However, weed biomass is the outcome after competition experienced by each weed species with the fellow crop and the weeds. Consequently, the weed pressure in the subsequent season will be the cumulative effect of the preceding season too, which is unaccounted for in CPWC. It is argued that in organic farming or low-input farming systems, where herbicides are not used, the concept of CPWC can be misleading and should be avoided. It is concluded that CTWR is more meaningful than the CPWC.
We present a broadband radio study of the transient jets ejected from the black hole candidate X-ray binary MAXI J1535–571, which underwent a prolonged outburst beginning on 2017 September 2. We monitored MAXI J1535–571 with the Murchison Widefield Array (MWA) at frequencies from 119 to 186 MHz over six epochs from 2017 September 20 to 2017 October 14. The source was quasi-simultaneously observed over the frequency range 0.84–19 GHz by UTMOST (the Upgraded Molonglo Observatory Synthesis Telescope) the Australian Square Kilometre Array Pathfinder (ASKAP), the Australia Telescope Compact Array (ATCA), and the Australian Long Baseline Array (LBA). Using the LBA observations from 2017 September 23, we measured the source size to be $34\pm1$ mas. During the brightest radio flare on 2017 September 21, the source was detected down to 119 MHz by the MWA, and the radio spectrum indicates a turnover between 250 and 500 MHz, which is most likely due to synchrotron self-absorption (SSA). By fitting the radio spectrum with a SSA model and using the LBA size measurement, we determined various physical parameters of the jet knot (identified in ATCA data), including the jet opening angle ($\phi_{\rm op} = 4.5\pm1.2^{\circ}$) and the magnetic field strength ($B_{\rm s} = 104^{+80}_{-78}$ mG). Our fitted magnetic field strength agrees reasonably well with that inferred from the standard equipartition approach, suggesting the jet knot to be close to equipartition. Our study highlights the capabilities of the Australian suite of radio telescopes to jointly probe radio jets in black hole X-ray binaries via simultaneous observations over a broad frequency range, and with differing angular resolutions. This suite allows us to determine the physical properties of X-ray binary jets. Finally, our study emphasises the potential contributions that can be made by the low-frequency part of the Square Kilometre Array (SKA-Low) in the study of black hole X-ray binaries.
Research has found that low mood including sadness and hopelessness is an important factor for decreased awareness in one’s oral health and lowered frequency of visit to the dental office, this relationship is not well studied in national representative samples. Poor mental wellbeing can lead to poor oral health.
Objectives
Aim is to examine the relationship between feeling sad or hopeless and awareness for dental care.
Methods
Data were obtained from the Youth Risk Behavior Surveillance Survey (YRBS-CDC), USA, for years 2009-2017. All ages from 12 to 18 years, feeling sad or hopeless and dental visits were identified. Univariable relationship between feeling sad or hopeless (>2 weeks in the past year) and dental office visits for all dental care (during the past 12 months, 12-24 months, >24 months, and never) was evaluated using chi-square test.
Results
Out of a total of 53,098 youths, 30.5% of youths were feeling sad or hopeless. Within the youths feeling sad or hopeless, the prevalence of youth who never received dental care was higher at 37.1% in comparison to youths who received dental care >24 months ago 36.4%,12-24 months 33.7%, and visited the dental office in the past 12 months 28.9%. (p<0.0001). In youths who had dental care in the last 12 months, the prevalence of sadness or hopelessness was lower at 65% vs 70%, while it was higher in youths who had never had dental care at 3.3% vs 1.7%.
Conclusions
Further research is warranted to evaluate reduced oral health care awareness among participants feeling sad or hopeless.
Guinea grass (Megathyrsus maximus Jacq.) is an important forage species in vast rangelands/grasslands of India and several tropical countries owing to its high biomass yield, good nutritional quality and wide adaptation. Evaluation of the existing natural variation and selection of desirable genotypes is the most plausible breeding method for this apomictic and polyploid grass. Developing a core sub-set to narrow down the number of germplasm required for future genetic studies is also pertinent. The present study involved characterization of 152 diverse M. maximus germplasm representing collections from different agro-ecological zones of India as well as those procured from Africa and Brazil; and development of a core sub-set. Nineteen metric, seven non-metric and nine nutritive traits together established the presence of wide variability among the genotypes. Clustering of the genotypes resulted in eight distinct clusters. The largest cluster included genotypes from Ethiopia, north India, north-western India, south India and north-eastern hill region, thus represented the highest diversity. Eleven of the total 26 Ethiopian genotypes clustered together. Non-metric morphological traits effectively differentiated the genotypes, and were associated with nutritional quality also. Genotypes which flowered once in a year showed slightly better crude protein and digestibility. The clusters were further sub-clustered and representatives were selected to develop the core sub-set of 23 genotypes comprising 20 indigenous and three exotic accessions. Comparison of the range of diversity and mean value for traits as obtained in the core sub-set and that in the total germplasm indicated successful capturing of maximum diversity in the core sub-set.
This study was carried out to compare the efficacy of different methods to activate buffalo A + B and C + D quality oocytes parthenogenetically and to study the in vitro developmental competence of oocytes and expression of some important genes at the different developmental stages of parthenotes. The percentage of A + B oocytes (62.16 ± 5.06%, range 53.8–71.3%) was significantly higher (P < 0.001) compared with that of C + D oocytes (37.8 ± 5.00%, range 28.6–46.1%) retrieved from slaughterhouse buffalo ovaries. Among all combinations, ethanol activation followed by culture in research vitro cleave medium gave the highest cleavage and blastocyst yields for both A + B and C + D grade oocytes. Total cell numbers, inner cell mass/trophectoderm ratio and apoptotic index of A + B group blastocysts were significantly different (P < 0.05) from their C + D counterpart. To determine the status of expression patterns of developmentally regulated genes, the expression of cumulus–oocyte complexes, fertilization, developmental competence and apoptotic-related genes were also studied in parthenogenetically produced buffalo embryos at different stages, and indicated that the differential expression patterns of the above genes had a role in early embryonic development.
The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together $60+$ programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.
There has been little reported on the transoral reconstructive options following salvage transoral robotic surgery. This paper describes the facial artery musculomucosal flap as a method to introduce vascularised tissue to a previously irradiated resection bed.
Methods
A facial artery musculomucosal flap was used to reconstruct the lateral pharyngeal wall in 13 patients undergoing salvage transoral robotic surgery for oropharyngeal squamous cell carcinoma. Outcomes recorded include flap and donor site complications, length of stay, and swallowing and speech outcomes.
Results
There were no immediate or late flap complications, or cases of delayed wound healing in this series. There were two facial artery musculomucosal related complications requiring surgical management: one bleed from the facial artery musculomucosal donor site and one minor surgical revision. Healing of the flap onto the resection bed was successful in all cases.
Conclusion
The facial artery musculomucosal flap provides a suitable transoral local flap option for selected patients undergoing salvage transoral robotic surgery for oropharyngeal malignancies.
Delivery by cesarean section (CS) is the most common surgical operation performed in the world. Cesarean rates vary across countries, ranging from over 50% in South American countries such as Chile, Argentina, and Brazil to over 32% in the United States and 25% of all deliveries in the United Kingdom.
Ludwigia is an important broadleaf weed of direct-seeded rice in Asia. Crop interference that relies on shading may have potential as a component of integrated weed management strategies but it requires understanding the extent to which rice can interfere with weed growth and how these weeds may respond. The growth of ludwigia was studied when grown alone and in competition with 4 and 12 rice (cv. IR72) plants. Rice interference reduced ludwigia height, number of branches, and shoot and root biomass. However, ludwigia showed the ability to reduce the effects of rice interference by increasing leaf weight ratio, increasing stem and leaf biomass in the upper half of the plant, and increasing specific stem length. At 11 wk after seeding, for example, ludwigia grown with 12 rice plants had 38% greater leaf weight ratio compared to plants grown alone. When grown with 12 rice plants, the weed had 82% of its leaf biomass in upper half of the plant compared to only 25% in weeds grown alone. The results showed that ludwigia responded to rice interference with a combination of adaptations typical of many weed species. Despite such plasticity, the control of ludwigia may be achieved by dense rice stands and increasing interference.
We describe a study of the E–W-trending South Wagad Fault (SWF) complex at the eastern part of the Kachchh Rift Basin (KRB) in Western India. This basin was filled during Late Cretaceous time, and is presently undergoing tectonic inversion. During the late stage of the inversion cycle, all the principal rift faults were reactivated as transpressional strike-slip faults. The SWF complex shows wrench geometry of an anastomosing en échelon fault, where contractional and extensional segments and offsets alternate along the Principal Deformation Zone (PDZ). Geometric analysis of different segments of the SWF shows that several conjugate faults, which are a combination of R synthetic and R’ antithetic, propagate at a short distance along the PDZ and interact, generating significant fault slip partitioning. Surface morphology of the fault zone revealed three deformation zones: a 500 m to 1 km wide single fault zone; a 5–6 km wide double fault zone; and a c. 500 m wide diffuse fault zone. The single fault zone is represented by a higher stress accumulation which is located close to the epicentre of the 2001 Bhuj earthquake of Mw 7.7. The double fault zone represents moderate stress at releasing bends bounded by two fault branches. The diffuse fault zone represents a low-stress zone where several fault branches join together. Our findings are well corroborated with the available geological and seismological data.
The acceleration of an electron beam by surface plasma waves (SPW), in the presence of external magnetic field parallel to surface and perpendicular to direction of propagation of SPW has been studied. This wave propagating along the $\hat z$-axis is excited using Kretschmann geometry, having maximum amplitude at the metal–vacuum interface. Equations of motion have been solved for electron energy and trajectory. The electron gains and retains energy in the form of cyclotron oscillations due to the combined effect of the static magnetic field and SPW field. The energy gained by the beam increases with the strength of magnetic field and laser intensity. In the present scheme, electron beams can achieve ~15 KeV energy for the SPW amplitude A1 = 1.6 × 1011 V/m, plasma frequency ωp = 1.3 × 1016 rad/s and cyclotron frequency ωc/ωp = 0.003.