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India’s plans to electrify transport is complicated by its reliance on coal-power. Here the authors call for diverse policy and technology solutions, including a focus on cleaner grids, electric 2-wheelers, and hybrid 4-wheelers in the near-term.

The dominant narrative in the affluent west is that climate change poses an “existential threat” and very rapid cuts in greenhouse gas (GHG) emissions and hence fossil fuel use are needed to avoid it. Simultaneously oil, gas, coal, aviation, steel and cement industries and livestock farming have to be largely shut down to eliminate GHG. This review argues that globally all this will not happen by 2050, let alone 2030 because the scale of the problem is too large. Transport is particularly difficult to decarbonize and current policies focusing entirely on battery electric vehicles will not and must not succeed. GHG levels are unlikely to come down significantly in the next several decades and even if they did, extreme weather events will not disappear. It is better to recognize such realities and make societies more resilient to the effects of climate change. Humanity will have to adapt to any further warming as it has successfully done with the previous warming of about 1.1 C over the past century. Combustion research, particularly of fossil fuels and in internal combustion engines is currently seen as unnecessary in many countries. However, it will be absolutely necessary, along with the development of the alternatives in order to ensure that energy use is improved since combustion will continue to be central to supplying global energy and driving transport for decades to come. The gap between current policies and reality will perhaps be bridged as energy security concerns come to the fore.

The global demand for transport energy is large, growing, and primarily met by petroleum-derived liquid fuels powering internal combustion engines (ICEs). Moreover, the demand for jet fuel and diesel is projected to grow faster than the demand for gasoline in the future, and is likely to result in low-octane gasoline components becoming more readily available. Significant initiatives with varying motivations are taking place to develop the battery electric vehicle (BEV) and the fuel cell as alternatives to ICE vehicles, and to establish fuels such as biofuels and natural gas as alternatives to conventional liquid fuels. However, each of these alternatives starts from a very low base and faces significant barriers to fast and unrestrained growth; thus, transport—and particularly commercial transport—will continue to be largely powered by ICEs running on petroleum-based liquid fuels for decades to come. Hence, the sustainability of transport in terms of affordability, energy security, and impact on greenhouse gas (GHG) emissions and air quality can only be ensured by improving ICEs. Indeed, ICEs will continue to improve while using current market fuels, through improvements in combustion, control, and after-treatment systems, assisted by partial electrification in the form of hybridization. However, there is even more scope for improvement through the development of fuel/engine systems that can additionally leverage benefits in fuels manufacture and use components that may be readily available. Gasoline compression ignition (GCI), which uses low-octane gasoline in a compression ignition engine, is one such example. GCI would enable diesel-like efficiencies while making it easier to control nitrogen oxides (NOx) and particulates at a lower cost compared with modern diesel engines. Octane on demand (OOD) also helps to ensure optimum use of available fuel anti-knock quality, and thus improves the overall efficiency of the system. Keywords: Transport energy, Internal combustion engines, Gasoline, Diesel

Currently 99.8% of global transport is powered by internal combustion engines (ICEs) and 95% of transport energy comes from liquid fuels made from petroleum. Many alternatives including battery electric vehicles (BEVs) and other fuels like biofuels and hydrogen are being considered. However, all these alternatives start from a very low base and face very significant barriers to unlimited expansion so that 85–90% of transport energy is expected to come from conventional liquid fuels powering combustion engines even by 2040. Hence it is imperative that ICEs are improved in order to reduce the local and global environmental impact of transport. This paper considers the scope for such improvement after discussing the basic principles that govern engine efficiency and the technologies to control exhaust pollution. The great scope for such improvement is illustrated by considering various practical approaches already in the market. For instance, the best in class SI engines in the U.S. have 14% lower fuel consumption compared to the average. Engine and conventional powertrain developments alone could reduce the fuel consumption by over 30% for light duty vehicles (LDVs). Implementing other technologies such as hybridisation and light-weighting could reduce fuel consumption by 50% compared to the current average for LDVs. Current after-treatment technology can ensure that the exhaust pollutant levels meet the most stringent current emissions requirements. Indeed, with the most modern diesel vehicles, the exhaust can be cleaner than the intake air in urban centres. The implications for transport policy, particularly where there are plans to ban ICEs, are considered in the final discussion. All available technologies need to be deployed to mitigate the environmental impact of transport and it would be extremely short-sighted to discourage further development of ICEs by limiting their sales.

Background and Objectives: Ultrasonography is the most effective way to date pregnancy and to estimate the fetal weight in obstetric clinics. Currently, the diaphyseal length of humerus is used as a new parameter to estimate gestational age. The study evaluates the diaphyseal length of humerus as a parameter to estimate the gestational age of the fetus at the time of examination and to assess the growth pattern of humerus with advancing gestational age. Methods: The study was done on 152 antenatal women aged between 20 to 30 years of gestational ages from 15 to 40 weeks from the district of Dharwad, Karnataka, Subjects with maternal disease known to affect normal fetal growth were excluded. The diaphyseal length of humerus was measured by radiologist in a standardized manner. The study describes the relationship of the diaphyseal length of humerus in centimeters, with the advancing gestational age in weeks. Results: It was observed that the diaphyseal length of humerus gradually increased from 15 weeks to 40 weeks of gestation and that the relationship is linear and direct. Normograms of diaphyseal lengths of humerus can be constructed by the formula derived by this study for this particular geographical area. Conclusion: The relationship between the diaphyseal length of humerus and the gestational age is linear and direct. The measurement of the diaphyseal lengths of humerus [in cm] can be an important additional parameter for estimating gestational age along with other parameters.

Different octane specification methods were evaluated under rising ethanol blending volumes by adopting a refinery economics model to represent a region in the U.S. It was demonstrated that the traditional octane specification methods, such as the Anti-knock Index (AKI) used in the U.S., or the Research Octane Number (RON) and Motor Octane Number (MON) used in the EU, can lead to counterintuitive drop in octane sensitivity with increased availability of ethanol. This is undesirable for modern gasoline engines that require fuels with high RON and low MON, but it is a consequence of how a refinery reformulates the gasoline blendstock, resulting in more naphtha being used in the final composition. The use of a new specification method based on octane index (OI), with engine constant K = −1, internalizes the diminishing role that MON plays in modern engines, thus ensures that the desirable anti-knock quality is being met either through higher RON and/or higher sensitivity. Initial assessment suggests a potential engine efficiency benefit (~ 1.5%) to be gained simply by switching from an AKI-based specification method to an equivalent OI-based method.

Background: Amid the health risk posed by coronavirus disease 2019 pandemic, all the educational institutions in India have adopted online teaching as a method of imparting education. Thus, the current study was executed to evaluate the perception and preparedness of dental students toward online learning in dental education. Materials and Methods: The present cross-sectional study was conducted on 286 dental undergraduate (UG) and postgraduate (PG) students employing a pretested questionnaire. The questionnaire focused on technological access, computer and online skills, and motivational skills to use e-learning for educational purpose. The response scale for each domain was classified into low readiness level (mean value = 1-<3), acceptable/moderate readiness level (mean value = 3-<4), and high readiness level (mean value = 4-5). Results: The results showed a high level of computer (4.02 ± 0.73) and online skills (4.05 ± 0.70) and acceptable levels of technology access (3.62 ± 0.73) and motivational level (3.61 ± 0.82). There was a significant difference in computer (P = 0.017) and online skills (P = 0.044) among UG and PG students, with PG students reporting better soft skills. Majority of the students reported participating in online workshops (68.2%) and examinations (76.6%). Around 55.2% of the students reported a positive impact and 8% reported a very positive impact of online methods on their learning. Conclusion: Students showed a high level of readiness toward e-learning methods along with some difficulties faced during e-learning. [ABSTRACT FROM AUTHOR]

Background: Anomalies and enamel hypoplasia of deciduous dentition are routinely encountered by dental professionals and early detection and careful management of such conditions facilitates may help in customary occlusal development. Objective: The aim of this study was to determine the prevalence of hypodontia, microdontia, double teeth, and hyperdontia of deciduous teeth among Indian children. Materials and Methods: The study group comprised 1,398 children (735 boys, 633 girls). The children were examined in department of Pedodontics and Preventive Dentistry in Jodhpur Dental College General Hospital, Jodhpur, Rajasthan, India. Clinical data were collected by single dentist according to Kreiborg criteria, which includes double teeth, hypodontia, microdontia, and supernumerary teeth. Statistical analysis of the data was performed using the descriptive analysis and chi-square test. Results: Dental anomalies were found in 4% of children. The distribution of dental anomalies were significantly more frequent (P = 0.001) in girls (5.8%, n = 38) than in boys (2.7%, n = 18). In relation to anomaly frequencies at different ages, significant difference was found between 2 and 3 years (P = 0.001). Conclusion: Double teeth were the most frequently (2.3%) observed anomaly. The other anomalies followed as 0.3% supernumerary teeth, 0.6% microdontia, 0.6% hypodontia. Identification of dental anomalies at an early age is of great importance as it prevents malocclusions, functional and certain psychological problems.

Background: To assess the knowledge, attitude, and practice of ergonomics among dental professionals of Hubli–Dharwad twin cities, India. Methods: Investigator-developed, self-administered, closed-ended questionnaire assessing knowledge, attitude, and practices regarding ergonomics during dental practice was filled in by undergraduates, house surgeons, postgraduates, and faculty members of dental institutions and private practitioners from Hubli–Dharwad twin cities. Results: Data were collected from a total of 250 participants, 50 belonging to each academic group. Overall mean knowledge, attitude, and practice scores were 52%, 75%, and 55%, respectively. Significant correlation was found for age with attitude (χ2 = 10.734, p = 0.030) and behavior (χ2 = 12.984, p = 0.011). Marital status was significantly associated with all the three domains; knowledge (χ2 = 29.369, p = 0.000), attitude (χ2 = 29.023, p = 0.000), and practices (χ2 = 13.648, p = 0.009). Conclusion: Participants had considerable awareness and behavior toward ergonomics in dental practice. The high attitude score indicates stronger acceptance of ergonomics principles and guidelines during routine dental procedures. The current study highlights the situation of ergonomics in dental practice in the form of knowledge, attitude, and practices.