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Exposure biases are a pervasive non‐climatic change in land air temperature records which have been introduced as a result of changes in the way thermometers were sheltered from solar radiation and the elements over time. Exposure biases have not been widely accounted for in observational records, due to difficulties detecting/correcting the bias using traditional homogenisation techniques; therefore, exposure biases still contribute significant uncertainty to the early period in global temperature compilations. Here, an empirical approach to address the bias arising from the introduction of Stevenson‐type screens from the late‐19th century is presented. The approach consists of: (1) an empirical analysis of 54 parallel measurement series to identify the characteristics of the exposure bias in four exposure classes; (2) the development of bias‐estimation models based on an analysis of which variables influence the bias; and (3) the application of the models to an extended version of CRUTEM5 (CRUTEM5_ext), based on exposure metadata, to quantify and reduce the bias. Step one identified differences between the temperatures recorded in Stevenson screens and early exposures, which vary seasonally, diurnally, and with location and exposure class. The largest biases (in mean temperatures) were found in freestanding exposures (up to −0.78°C annually) and in summer, while the smallest biases were generally found in wall‐mounted exposures (near‐0°C annually) and in winter. Significant relationships between the bias and temperature, downward top of atmosphere and/or received shortwave downward solar radiation were found in each exposure class and led to the development of three regression‐based bias‐estimation models. Application of these models to 1,960 mid‐latitude stations in CRUTEM5_ext, resulted in small (≤0.016°C) positive adjustments to the Northern Hemisphere mid‐latitude mean before 1880, and larger (≤−0.1°C) negative adjustments to the Northern and Southern Hemisphere mid‐latitude means between 1882–1934 and 1856–1900, respectively. Larger adjustments were estimated regionally: up to −0.57°C annually and −0.79°C seasonally in individual grid cells. [ABSTRACT FROM AUTHOR]

AZ91D, a die‐casted alloy, offers several benefits (better saltwater corrosion resistance, suitable castability, and good atmospheric stability) over other grades of magnesium alloy. However, it cannot overcome the challenging requirements of advanced applications in its current form. Extensive research in coating technologies is crucial in enhancing the performance of AZ91D alloy in highly corrosive environments (coastal and marine, industrial, farm, etc.). The high corrosion resistance of AZ91D for various applications is achievable through the deposition of different materials. Developments in coating materials and techniques, with their influence on the corrosion protection behavior of AZ91D alloy, over the last decade (2012–2022), are focused on in this study. It is observed that composite, biodegradable, and self‐healing coatings are gaining popularity. The transition in the coating technology, from conventional to self‐healing coating materials and from conventional to environment‐friendly coating techniques, is a vital part of this discussion. This review further explores how different additives, pre‐treatments, post‐treatments, and corrosion inhibitors affect the corrosion performance of coatings. This study helps select the optimum coating material for AZ91D magnesium alloy to fulfil a specific application requirement and guides toward technological developments in this segment. [ABSTRACT FROM AUTHOR]

Background: Facial skin characteristics and appearance vary according to ethnicity. While much of this knowledge is derived from the Caucasian population, lately there have been efforts to gain such understanding in various regions in Asia. In this paper, we have built an understanding of such features in Indonesia. In Indonesia, a section of females wears a traditional veil (hijab) to cover the scalp and part of face. The influence of the hijab on facial skin attributes was also investigated. Methods: In a cross‐sectional observational study design involving 419 female volunteers in Jakarta, Indonesia, facial skin attributes (colour, radiance, hydration, trans‐epidermal water loss [TEWL], wrinkles, fine lines, pores, and sebum levels) and conditions (melasma, post‐inflammatory hyperpigmentation (PIH), solar lentigines/ senile lentigines, seborrheic keratoses and acne) were assessed by trained operators and dermatologists using standard validated instruments and scales. Results: With age, facial skin colour showed darkening in cheek; forehead on the other hand showed slight lightening. The skin evenness and radiance decreased, substantially. Aging attributes measured in terms of lines, wrinkles, and under‐eye dark circles showed deterioration with age; the decline was progressively faster than colour change. Facial image data analysis corroborated these findings. Skin hydration remained similar across the age groups even though the skin barrier function measured in terms of TEWL improved with age. Sebum levels in the skin were similar up to the age of 50 but declined in the next group of 50–60 year. Pore severity increased with age. Melasma, seborrheic keratosis and PIH showed a high prevalence (>∼50%) at the young age group (20–30 years), itself. Melasma prevalence attained 100% in the age group of 41–50 year and onwards, and its severity similarly showed a steady rise with age. PIH on the other hand showed a steady decline with age. Solar lentigines prevalence (∼30%) did not change much across age groups, and the severity scores were similar in age groups up to 50 year but increased substantially in 51–60‐year age groups. Seborrheic keratosis was similar (∼47%) in age groups up 20–40 year but steadily increased in upper age groups. Its severity was similar in the age groups of 20–30 year and 31–40 year but showed a two‐fold increase in subsequent age groups. Acne was 10% in the age group of 20–30 year and declined gradually to 0.7% in the 51–60‐year age group. Hijab wearers showed slight protection in skin colour darkening and improvement of evenness and radiance but were similar on aging (fine lines and wrinkles on crow's feet, under eye and peri‐oral areas) markers to non‐wearers. In general, in majority of age‐groups, hijab wearers showed a higher prevalence of melasma, solar/senile lentigines, seborrheic keratosis and PIH. [ABSTRACT FROM AUTHOR]

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The authors have proposed an inverter resistor capacitor (IRC)‐based simple chaotic ring oscillator with dual feedback for the generation of the chaotic waveform. The proposed chaotic system uses three coupled autonomous first‐order differential equations and it can be electrically demonstrated using the complementary metal oxide semiconductor (CMOS) inverters with few passive RC elements for the generation of the high‐frequency strange attractor. The basic dynamical characteristics and multistability property with complex bifurcation pattern in a wide range of parameters are well observed through theoretical as well as numerical simulation analysis using scaled inverse tangent function. In addition, a simple IRC chaotic model design is investigated using 0.18μm MOS transistor parameters with grounded capacitors and an equivalent CMOS‐based scaled inverse tangent function. Moreover, the Cadence post layout simulation gives useful information about the circuit sustainability for IC design with high frequency (MHz), low power dissipation (940 μW) and small chip area (826.3 μm2). [ABSTRACT FROM AUTHOR]

The positive Indian Ocean Dipole (IOD) event in 2019 was among the strongest on record, while the Indian Summer monsoon (ISM) was anomalously dry in June then very wet by September. We investigated the relationships between the IOD, Pacific sea surface temperature (SST), and ISM rainfall during 2019 with an atmospheric general circulation model forced by observed SST anomalies. The results show that the extremely positive IOD was conducive to a wetter‐than‐normal ISM, especially late in the season when the IOD strengthened and was associated with anomalous low‐level divergence over the eastern equatorial Indian Ocean and convergence over India. However, a warm SST anomaly in the central equatorial Pacific contributed to low‐level divergence and decreased rainfall over India in June. These results help to better understand the influence of the tropical SST anomalies on the seasonal evolution of ISM rainfall during extreme IOD events. Plain Language Summary: A prominent pattern of variability in the Indian Ocean is a seesaw in sea surface temperature (SST) between the eastern and western sides of the Ocean basin, called the Indian Ocean Dipole (IOD). Its influence on the regional weather and climate is not yet fully established, but the extremely strong IOD event in 2019 provided us the opportunity to consider its impact on the Indian Summer Monsoon. By simulating the response to the anomalous SST patterns that occurred in 2019, and by observation‐based analyses, we find evidence that the IOD did influence the monsoon rainfall in 2019, but that SST anomalies in the Pacific Ocean were also important. Our simulations show that the positive IOD was conducive to wetter‐than‐normal conditions throughout and especially at the end of the monsoon season, but that anomalous warmth in the central equatorial Pacific may have contributed to reduced rainfall in June over India. The results from this study help to understand the role of SST anomalies within and outside the Indian Ocean in affecting ISM rainfall intensity and seasonal evolution during extreme IOD events. Key Points: The positive Indian Ocean Dipole event that occurred in 2019 was among the strongest in the modern instrumental recordThe 2019 Indian Summer monsoon was drier than usual in June then wetter in the following months, resulting in above‐normal seasonal rainfallThe seasonal evolution of ISM was partly driven by a combination of equatorial Pacific and Indian Ocean sea surface temperature anomalies [ABSTRACT FROM AUTHOR]

Over geological timescales, mountain building or orogenesis is associated with increased weathering, the drawdown of atmospheric CO2, and global cooling. However, a multimillion‐year delay appears to exist between peaks in low‐latitude mountain uplift and the maximum extent of Phanerozoic glaciation, implying a more complex causal relationship between the two. Here we show that global silicate weathering can be modulated by orogeny in three distinct phases. High, young mountain belts experience preferential precipitation and the highest erosion. As mountains are denuded, precipitation decreases, but runoff temperature rises, sharply increasing chemical weathering potential and CO2 drawdown. In the final phase, erosion and weathering are throttled by flatter topography. We conclude that orogeny acts as a capacitor in the climate system, granting the potential for intense transient CO2 drawdown when mountain ranges are denuded; the mechanism suggests such a scenario potentially happening 10–50 × 106 years in the future. Plain Language Summary: Over timescales of tens of millions of years or more, plate tectonics can raise large mountain ranges. CO2 can be removed from the atmosphere through a complex series of processes involving the weathering of rocks, which depends on processes such as rainfall, which in turn is affected by the presence of mountains. The result is that mountain ranges are associated with a reduction of atmospheric CO2 and global cooling on these very long timescales. An analysis of geological data suggests a multimillion‐year delay between peaks in mountain range uplift at low latitudes and the maximum extent of glaciation over the last 400 × 106 years. Our manuscript explains the delay using two numerical or computer models: a climate and circulation model and a geochemical model that simulates weathering processes. We show that weathering, and the implied reduction of atmospheric CO2, happens most intensely when mountain ranges are eroded, because the ability of weathering to remove CO2 depends not just on precipitation but also on the temperature of river runoff. Our mechanism intriguingly suggests such a scenario potentially happening 10‐50 × 106 years in the future associated with projected changes to the height of the Tibetan plateau. Key Points: A multimillion‐year delay appears to exist between peaks in low‐latitude mountain uplift and the maximum extent of Phanerozoic glaciationWe describe a mechanism to explain the delay using a combination of climate and geochemical modeling of the periods surrounding upliftThe mechanism suggests such a scenario potentially happening 10–50 × 106 years in the future [ABSTRACT FROM AUTHOR]

Abstract: To explore the mechanisms linking Arctic sea ice loss to changes in midlatitude surface temperatures, we conduct idealized modeling experiments using an intermediate general circulation model and with sea ice loss confined to the Atlantic or Pacific sectors of the Arctic (Barents‐Kara or Chukchi‐Bering Seas). Extending previous findings, there are opposite effects on the winter stratospheric polar vortex for both large‐magnitude (late 21st century) and moderate‐magnitude sea ice loss. Accordingly, there are opposite tropospheric Arctic Oscillation (AO) responses for moderate‐magnitude sea ice loss. However, there are similar strength negative AO responses for large‐magnitude sea ice loss, suggesting that tropospheric mechanisms become relatively more important than stratospheric mechanisms as the sea ice loss magnitude increases. The midlatitude surface temperature response for each loss region and magnitude can be understood as the combination of an “indirect” part induced by the large‐scale circulation (AO) response, and a residual “direct” part that is local to the loss region. [ABSTRACT FROM AUTHOR]

Clear-air turbulence (CAT) is one of the largest causes of weather-related aviation incidents. Here we use climate model simulations to study the impact that climate change could have on global CAT by the period 2050-2080. We extend previous work by analyzing eight geographic regions, two flight levels, five turbulence strength categories, and four seasons. We find large relative increases in CAT, especially in the midlatitudes in both hemispheres, with some regions experiencing several hundred per cent more turbulence. The busiest international airspace experiences the largest increases, with the volume of severe CAT approximately doubling over North America, the North Pacific, and Europe. Over the North Atlantic, severe CAT in future becomes as common as moderate CAT historically. These results highlight the increasing need to improve operational CAT forecasts and to use them effectively in flight planning, to limit discomfort and injuries among passengers and crew. [ABSTRACT FROM AUTHOR]

ABSTRACT High-performance polymer nanocomposites based on poly(aryletherketone) (PAEK) as matrix and hexagonal boron nitride (h-BN) nanopowder as reinforcement were fabricated using planetary ball mill followed by hot pressing. The addition of h-BN (0-5 wt %) to the matrix enhanced the microhardness and thermal stability compared to pure matrix. For a constant sliding speed, the wear rate of the nanocomposites determined by using Pin-on-Disk tribometer was reduced approximately 22 times compared to pure matrix. The coefficient of friction of the nanocomposites is slightly increased but it is stable compared to that of pure matrix. It was also investigated that the thermal stability of the debris of the nanocomposites was decreased compared to the pure matrix and its nanocomposites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44409. [ABSTRACT FROM AUTHOR]

The South Pacific Convergence Zone (SPCZ) is a northwest-southeast oriented precipitation bandover the South Pacific Ocean. Latent heat release fromcondensation leads tosubstantial diabatic heating, which has potentially large impacts on local and global climate. The influence of this diabatic heating within the SPCZ is investigated using the Intermediate General Circulation Model (IGCM4). Precipitation in the SPCZ has been shown to be triggered by transient Rossby waves that originate in the Australian subtropical jet and are refracted towards the equatorial eastern Pacific. A Rossby wave triggers a SPCZ 'convective event', with associated diabatic heat release and vortex stretching. Consequently, the Rossby wave is dissipated in the SPCZ region. These features are simulated well in a control integration of IGCM4. In an experiment, convective heating is prescribed to its 'climatological' value in the SPCZ region during the Rossby wave 'events' and dynamic forcing from Rossby waves is decoupled from the usual thermodynamic response. In this experiment Rossby waves over the SPCZ region are not dissipated, confirming the vortex stretching mechanism from previous studies. Furthermore, the change in Rossby wave propagation has an impact on momentum transport. Overall, the effect of the Rossby wave-induced convection in the SPCZ is to decrease the strength of the Pacific subtropical jet and the equatorial eastern Pacific upper-tropospheric westerlies, by about 2-6 m s-1. Following these changes to the basic state, two potential feedbacks in the SPCZ and larger Pacific climate system are suggested: increased SPCZ convection due to the enhancement of negative zonal stretching deformation in the SPCZ region and decreased equatorward refraction of Rossby waves into the westerly duct leading to less SPCZ 'events'. As the convective events in the SPCZ have a significant impact on Pacific mean climate, it is crucial that the SPCZ is represented correctly in climate models. [ABSTRACT FROM AUTHOR]

The South Pacific Convergence Zone (SPCZ) and South Atlantic Convergence Zone (SACZ) are diagonal bands of precipitation that extend from the Equator southeastward into the Southern Hemisphere over the western Pacific and Atlantic Oceans, respectively. With mean precipitation rates over 5 mm day-1, they are a major component of the tropical and global climate in austral summer. However, their basic formation mechanism is not fully understood. Here, a conceptual framework for the diagonal convergence zones is developed, based on calculations of the vorticity budget from reanalysis and Rossby wave theory. Wave trains propagate eastward along the Southern Hemisphere subtropical jet, with initially quasi-circular vorticity centres. In the zonally sheared environment on the equatorward flank of the jet, these vorticity centres become elongated and develop a northwest-southeast tilt. Ray-tracing diagnostics in a non-divergent, barotropic Rossby wave framework then explain the observed equatorward propagation of these diagonal vorticity structures toward the westerly ducts over the equatorial Pacific and Atlantic. The baroclinic component of these circulations leads to destabilisation and ascent ahead of the cyclonic vorticity anomaly in the wave, triggering deep convection because of the high sea surface temperatures in this region. Latent heat release then forces additional ascent and strong upper-tropospheric divergence, with an associated anticyclonic vorticity tendency. A vorticity budget shows that this cancels out the advective cyclonic vorticity tendency in the wave train over the SPCZ, and dissipates the wave within a day. The mean SPCZ is consequently comprised of the sum of these pulses of diagonal bands of precipitation. Similar mechanisms also operate in the SACZ. However, the vorticity anomalies in the wave trains are stronger, and the precipitation and negative feedback from the divergence and anticyclonic vorticity tendency are weaker, resulting in continued propagation of the wave and a more diffuse diagonal convergence zone. [ABSTRACT FROM AUTHOR]

Arjuna ( Terminalia arjuna) is a medicinal plant used in many polyherbal hepatoprotective formulations. Although widely claimed to be antioxidant, data supporting such actions of Arjuna are limited. In the present study, we have investigated the efficacy of the aqueous extract of T. arjuna (AETA) using a standard pro-oxidant [tertiary butyl hydroperoxide (TBHP)] in HepG2 cells. Cells were incubated with AETA (5-100 µg/ml) for a range of time points (4-24 h) with or without TBHP (500 μM), and biochemical markers of oxidative stress (OS) were determined. Cells incubated with TBHP showed the significant induction of OS response in cytosol manifested as lipid hydroperoxide (76%-198%) and the generation of reactive oxygen species (60%-127%). Diminished levels of reduced glutathione (35%-60%) and total antioxidant capacity (20%-61%) suggested an altered redox state. Significant perturbations in the activities of antioxidant enzymes such as catalase (30%-56%), superoxide dismutase (25%-68%), glutathione S-transferase (29%-67%), glutathione peroxidase (24%-68%) and glutathione reductase (38%-49%) were discernible suggesting the ongoing OS in the cells. However, cells treated with AETA (100 µg/ml) along with TBHP offered significant protection by reducing levels of lipid hydroperoxide (33%-62%) and ROS (69%) and by increasing antioxidant capacity (54%-81%) and levels of reduced glutathione (49%-82%). Further, it also enhanced the activities of endogenous antioxidant enzymes (superoxide dismutase, 60%; catalase, 35%-82%; glutathione peroxidase, 42-65 %; glutathione reductase, 48%-62%; and glutathione S-transferase, 22%-100%). Taken together, these data suggest that Arjuna can protect against the oxidative damage induced by TBHP and may be effectively used as a hepatoprotective adjuvant to abrogate OS in vivo. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The effect of a tea fortified with five herbs selected from Indian traditional medicine (Ayurveda) for their putative immunoenhancing effect ( Withania somnifera, Glycyrrhzia glabra, Zingiber officinale, Ocimum sanctum and Elettaria cardamomum) on innate immunity was investigated. Ex vivo natural killer (NK) cell activity was assessed after consumption of fortified tea compared with regular tea in two independent double-blind intervention studies. Both studies were conducted in India with healthy volunteers (age ≥ 55 years) selected for a relatively low baseline NK cell activity and a history of recurrent coughs and colds. In a pilot study conducted with 32 volunteers, the consumption of Natural Care tea significantly improved the NK cell activity of the volunteers in comparison with a population consuming regular tea. These results were validated in an independent crossover study with 110 volunteers. Data from these two studies indicate that regular consumption of the tea fortified with Ayurvedic herbs enhanced NK cell activity, which is an important aspect of the (early) innate immune response to infections. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The kinetics of the bacteriorhodopsin photocycle, measured by voltage changes in a closed membrane system using the direct electrometrical method (DEM) of Drachev, L.A., Jasaitus, A.A., Kaulen, A.D., Kondrashin, A.A., Liberman, E.A., Nemecek, I.B., Ostroumov, S.A., Semenov, Yu, A. & Skulachev, V.P. (1974) Nature 249 , 321–324 are sixfold slower than the kinetics obtained in optical studies with suspensions of purple membrane patches. In this study, we have investigated the reasons for this discrepancy. In the presence of the uncouplers carbonyl cyanide m -chlorophenylhydrazone or valinomycin, the rates in the DEM system are similar to the rates in suspensions of purple membrane. Two alternative explanations for the effects of uncouplers were evaluated: (a) the ‘back-pressure’ of the Δµ H+ slows the kinetic steps leading to its formation, and (b) the apparent difference between the two systems is due to slow major electrogenic events that produce little or no change in optical absorbance. In the latter case, the uncouplers would decrease the RC time constant for membrane capacitance leading to a quicker discharge of voltage and concomitant decrease in photocycle turnover time. The experimental results show that the primary cause for the slower kinetics of voltage changes in the DEM system is thermodynamic back-pressure as described by Westerhoff, H.V. & Dancshazy, Z. (1984) Trends Biochem. Sci. 9 , 112–117. [ABSTRACT FROM AUTHOR]