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Andrea Georgiou, Reshma Ramesh, Peter Schofield, Patrick White, Timothy H Harries School of Population Health & Environmental Sciences, King’s College London, London, UKCorrespondence: Timothy H Harries, King’s College London, Department of Population Health Sciences, School of Life Course & Population Sciences, King’s College London, 3rd Floor Addison House, Guys Campus, London, SE1 1UL, UK, Tel +44 20 7836 5454, Email timothy.harries@kcl.ac.ukBackground: Inhaled corticosteroid (ICS) therapy has been demonstrated to reduce the risk of COPD exacerbations. It should only be prescribed to COPD patients who are not adequately controlled by dual long-acting bronchodilator therapy and who have ≥ 2 exacerbations per year and a blood eosinophil count ≥ 300cells/μL. ICS therapy is widely prescribed outside guidelines to COPD patients, making ICS withdrawal an important consideration. This systematic review aims to provide an up-to-date analysis of the effect of ICS withdrawal on exacerbation frequency, change in lung function (FEV1) and to determine the proportion of COPD patients who resume ICS therapy following withdrawal.Methods: Randomised controlled trials (RCTs) and observational studies which compared ICS withdrawal with ICS continuation treatment were included. Cochrane Central, Web of Science, CINHAL, Embase and OVID Medline were searched. Risk of bias was assessed using the Cochrane RoB2 tool and the Newcastle-Ottawa Scale. Quality assessment of RCTs was conducted using GRADE. Meta-analysis of post-hoc analyses of RCTs of ICS withdrawal, stratified by blood eosinophil count (BEC), was undertaken.Results: Ten RCTs (6642 patients randomised) and 6 observational studies (160,029 patients) were included in the results. When ICS was withdrawn and long-acting bronchodilator therapy was maintained, there was no consistent difference in exacerbation frequency or lung function change between the ICS withdrawal and continuation trial arms. The evidence for these effects was of moderate quality. There was insufficient evidence to draw a firm conclusion on the proportion of patients who resumed ICS therapy following withdrawal (estimated range 12– 93% of the participants).Discussion: Withdrawal of ICS therapy from patients with COPD is safe and feasible but should be accompanied by maintenance of bronchodilation therapy for optimal outcomes.Keywords: COPD, inhaled corticosteroid, drug withdrawal, exacerbations, randomised controlled trials, observational studies

Orbital angular momentum (OAM) and torque transfer play central roles in a wide range of magnetic textures and devices including skyrmions and spin-torque electronics. Analogous topological structures are now also being explored in ferroelectrics, including polarization vortex arrays in ferroelectric/dielectric superlattices. Unlike magnetic toroidal order, electric toroidal order does not couple directly to linear external fields. Instead, we find that the presence of an electric toroidal moment in a ferrorotational phase transfers measurable torque and OAM to a localized electron beam in the ballistic limit. We record these torque transfers from a high-energy electron beam using a momentum-resolved detector. This approach provides a high-sensitivity method to detect polarization fields and their more complex order parameters and topologies. In addition to toroidal order, we also demonstrate high-precision measurements of vorticity and chirality for polar vortexlike phases.

The past decade has witnessed dramatic progress related to various aspects of emergent topological polar textures in oxide nanostructures displaying vortices, skyrmions, merons, hopfions, dipolar waves, or labyrinthine domains, among others. For a long time, these nontrivial structures (the electric counterparts of the exotic spin textures) were not expected due to the high energy cost associated with the dipolar anisotropy: the smooth and continuous evolution of the local polarization to produce topologically protected structures would result in a large elastic energy penalty. However, it was discovered that the delicate balance and intricate interplay between the electric, elastic, and gradient energies can be altered in low-dimensional forms of ferroelectric oxide nanostructures. These can be tuned to manipulate order parameters in ways once considered impossible. This review addresses the historical context that provided the fertile background for the dawning of the polar topological era. This has been possible thanks to a fruitful, positive feedback between theory and experiment: advances in materials synthesis and preparation (with a control at the atomic scale) and characterization have come together with great progress in theoretical modeling of ferroelectrics at larger length and timescales. An in-depth scientific description to formalize and generalize the prediction, observation, and probing of exotic, novel, and emergent states of matter is provided. Extensive discussions of the fundamental physics of such polar textures, a primer explaining the basic topological concepts, an explanation of the modern theoretical and computational methodologies that enable the design and study of such structures, what it takes to achieve deterministic, on-demand control of order-parameter topologies through atomically precise synthesis, the range of characterization methods that are key to probing these structures, and their thermodynamic field-driven (temperature-driven, stress-driven, etc.) susceptibilities are included. The new emergent states of matter join together with exotic functional properties (such as chirality, negative capacitance, and coexistence of phases) that, along with their small size and ultrafast dynamical response, make them potential candidates in multifunctional devices. Finally, some open questions and challenges for the future are presented, underlining the interesting future that is anticipated in this field.

Studies of rainfall variation generally focus on large areas. For example, in India, the area average monsoon rainfall series of the whole country or meteorological subdivisions are used. This would be of no use for local agriculture, particularly in places where rainfall is very high or very low, especially for crops like small cardamom and vanilla which are very sensitive to soil moisture and atmospheric air relative humidity. With this view, we present the data and analysis of the long term rainfall variations in semi arid as well as tropical humid environments in cardamom hill slopes in south-WesternGhats in India. In our analysis, the semi-arid cardamom hill slopes showed decreasing trend in rainfall over the recent past three decades ranging from 2.7 to 3.4 mm/yr with R2 values ranging from 0.42 to 0.85 (P= 0.05). Year-to-year variation in rainfall was considerable. No alternating pattern of increase and decrease in rainfall was seen in decads, epochal trends as accounted by ISM for the rest of the country were absent. If the present trend continues, agricultural production in this semi-arid, poor rain fed system will suffer, unless conservation and mitigation efforts are undertaken. In case of windward side humid tropics, the year- to- year variations in the monthly rainfall values were very large. For example, January and February rainfall values changed by a factor as high as two or more from one year to another. The lowest rainfall during a period was reported in 1987 which was one of the intense El-Nino years. There was a strong association of El-Nino phenomenon with below average rainfall (67% of the El-Nino years), indicating a good ENSO relationship. In case of La-Nina years, fifty per cent of the years had enjoyed excess rainfall. However, the impact of El-Nino phenomenon was not severe during the first pentad of this century (2000-2005) in this mountain range. This indicates that the relationship seems to have weakened. The coefficient of variation of rainfall for the entire data series ranged from 9 to 27%. The decadal averages for the first three decades (1896-1925) and the last three decades (1976-2005) studied, reported less than the annual mean (5000 mm) for the whole period (1896-2005). Only during the middle period (1926-1975) the decadal average rainfall exceeded the series annual mean.

Roshni Ramesh,* Anoop Sasi,* Shahana C Mohamed, Sonia P Joseph Department of Periodontology, Government Dental College, Thiruvananthapuram, Kerala, India*These authors contributed equally to this workCorrespondence: Roshni Ramesh, Department of Periodontology, Government Dental College, Thiruvananthapuram, Kerala, India, Email roshniarun73@gmail.comPurpose: Compression necrosis refers to bone tissue damage that can occur when excessive pressure or force is applied to surrounding bone during implant placement. This pressure can compromise blood supply to the bone, leading to necrosis. Compression necrosis is a concern, because it can affect the stability and long-term success of dental implant.Patients and Methods: This case report highlights a case of early bone loss and implant failure possibly due to compression necrosis. Clinical data, photographs, radiographs, blood examination report and histology were presented to document the early failure of an implant placed in the mandibular left posterior region of a 33-year-old female patient.Results: Radiograph taken six weeks after implant placement showed severe angular defect. Therefore, the implant was surgically removed. Histological examination of the area showed bony trabeculae with an absence of osteoblastic riming, suggestive of necrotic bone.Conclusion: Using excessive torque values when placing implants in dense bones can increase the risk of implant failure due to bone over compression. Dental professionals must follow the manufacturer’s instructions and employ quality surgical techniques during implant placement into dense cortical bone to minimise risks.Keywords: bone loss, dental implants, implant failure, necrosis

Recently, the electrical switching of antiferromagnetic (AFM) order has been intensively investigated because of its application potential in data storage technology. Herein, we report the current switching of the AFM Néel vector in epitaxial Pd/CoO films as a function of temperature. Using combined measurements of Hall resistance (HR) and x-ray magnetic linear dichroism (XMLD) below and above the AFM Néel temperature, we unambiguously identified both magnetic and nonmagnetic contributions to the current-induced HR change. Through magnetic field-induced HR measurements, we quantitatively determined the percentage of current-induced CoO spin switching. Further, we showed that the thermal effect dominated the CoO magnetic switching more in samples with a thinner Pd layer and that samples with a thicker CoO layer required higher thermal activation for current-induced magnetic switching. These results provide a clear and comprehensive picture of current-induced AFM spin switching across the AFM Néel temperature.