Search

Chemical synthesis of natural products is typically inspired by the structure and function of a target molecule. When both factors are of interest, such as in the case of taxane diterpenoids, a synthesis can both serve as a platform for synthetic strategy development and enable new biological exploration. Guided by this paradigm, we present here a unified enantiospecific approach to diverse taxane cores from the feedstock monoterpenoid (S)-carvone. Key to the success of our approach was the use of a skeletal remodeling strategy which began with the divergent reorganization and convergent coupling of two carvone-derived fragments, facilitated by Pd-catalyzed C-C bond cleavage tactics. This coupling was followed by additional restructuring using a Sm(II)-mediated rearrangement and a bioinspired, visible-light induced, transannular [2 + 2] photocycloaddition. Overall, this divergent monoterpenoid remodeling/convergent fragment coupling approach to complex diterpenoid synthesis provides access to structurally disparate taxane cores which have set the stage for the preparation of a wide range of taxanes.

The development of road traffic facilities is progressing rapidly in both developed and developing countries. However, the number of deaths caused by road traffic accidents is still increasing and the families of the accident victims are trapped in poverty. This study by taking Indonesia as a case aimed: (1) to investigate the perceptions of road users in viewing road traffic facilities on traffic accidents, means of reducing the fatality of traffic accident victims, types of fatality of road traffic accident victims, and type of transportation mode causing traffic accidents and fatalities of accidents victims, (2) to determine factors affecting the frequency of traffic accidents and the fatality of accident victims, and (3) to examine the correlation between traffic accident victims and poverty. The data source was obtained by distributing questionnaires to 600 sample respondents in ten provinces in Indonesia, categorized as having high death rates in road traffic accident areas. These data were then analyzed using qualitative and quantitative methods. The qualitative results show that most respondents viewed road traffic facilities as useful in reducing the frequency of traffic accidents and the fatality of traffic accident victims. The motorcycle was viewed as the type of transportation with great potential for road traffic accidents. However, the type of fatality in traffic accidents tends to be minor injuries. The quantitative results indicated that factors that significantly affect the chances of never having traffic accidents are the presence of traffic control officers, location, age, and the use of private vehicles. The traffic facilities (excluding ambulances and helmets) are insignificant in reducing traffic accidents. The significant factors affecting the fatality rate were the availability of accident prevention facilities, location, the use of private vehicles, and weather conditions. Traffic accidents were found to correlate with poverty incidence as they incur treatment costs, lost productivity, and the loss of a breadwinner in the family. These findings complement and sharpen previous empirical findings and suggest practical contributions to the government and traffic authorities to improve road traffic facilities and reduce traffic accidents, the fatality of traffic accident victims, and poverty.

Advances in predicting thunderstorms have been made possible through the use of artificial intelligence. Convolution neural networks, inspired by the processes of the human brain, are particularly effective in image classification. In particular, one-dimensional convolution neural networks have played a significant role in time series analysis, including thunderstorm forecasting. Unfortunately, these models face challenges when used with unbalanced datasets, where the proportion of events of interest, such as thunderstorms, is significantly lower than other phenomena. To overcome this limitation, several over-sampling and under-sampling strategies have emerged. In this paper, we propose a method for forecasting thunderstorm occurrences in the northern region of Chile using a one-dimensional convolutional neural network, combined with a balanced batch generator and attention models. The algorithm developed to predict thunderstorm days achieved a performance metric of approximately 79.6%, a promising result due to the minimal failure rates observed.

Mature fetiform teratoma, or homunculus, is a term coined for a rare variant of teratoma with a prevalence of 0.01% of teratomas. There have been very few cases reported in the world, and its thoracic presentation is extremely unusual. We present the case of a 31-year-old female patient with a history of progressive chest pain in the left hemithorax, associated with dyspnea on moderate exertion and cough. Imaging studies revealed a large intrathoracic tumor visually compatible with a teratoma. Surgical resection by a clamshell approach was successful, and subsequent anatomopathological studies of the operative specimen concluded that the mass was a mature fetiform thoracic teratoma. The treatment of this entity is generally surgical and includes wide resection due to its large adhesive component to surrounding tissues. Thus, the cardiothoracic surgeon must know approaches that allow wide resection, making these cases true surgical challenges.

The island of Java is the smallest of the six major islands in Indonesia. It is, however, the centre of national economic activity because 75% of industrial areas are located on this island, accounting for 59% of the national gross domestic product. The movement of goods on the island of Java reached 160.5 million tons, with trucks accounting for 90.3% of the total, contributing to traffic congestion. The ratio of road capacity to traffic volume on various major roads reached 1.3. This study aims to investigate how to reduce this ratio to 0.8 on the roads of Java by developing a short sea shipping transportation route from Jakarta to Surabaya. This study has never been conducted by the Ministry of Transportation of the Republic of Indonesia. According to the findings of the study, the potential cargo for short sea shipping reached 3.98 million twenty-foot equivalent units (TEUs). One of the most suitable types of vessels to be developed is the motorised container barge (MCB), which could operate on 88 voyages per year and have a capacity of 900 or 1,000 TEUs. The freight rate for short sea shipping ranges from $ 447 to $ 458 per TEUs, resulting in a benefit-cost ratio of 1.5 at a load factor of 70%. The freight rate is less expensive than the truck freight rate after adding the cost of trucking to and from the hinterland.

The development of red boxes for motorcycles in Indonesia was initially adopted from the advanced stop line (ASL) for bicycles. The bike box concept was adopted for motorcycles in Indonesia. To date, red boxes have been fully implemented in 21 cities in Indonesia. The purpose of this study is to analyze the effect of traffic light countdown timers and motorcycle lanes as an approach to the red box for motorcycles at signalized intersections. There were four locations studied in Denpasar Bali, i.e., red boxes with countdown timer only (Condition 1), red boxes with motorcycle lane only (Condition 2), red boxes with countdown timer and motorcycle lane (Condition 3), and red boxes without countdown timer and without motorcycle lane (Condition 4). The analysis results based on motorcycle volume data indicate that a countdown timer has a significant effect in increasing motorcycle acceleration when the green light starts, reducing the possibility of motorized vehicles other than motorcycles stopping in the red box area and reducing stop line violations while waiting during a red light. Meanwhile, the presence of a motorcycle lane as an approach lane to enter the red box area has a significant influence on increasing the occupancy of the red box by motorcycles. In addition, the correlation test shows that the countdown timer has a strong correlation with the occupancy of the red box to capacity and to stop line violation. Meanwhile, the level of traffic flow is strongly correlated with the countdown timer and motorcycle lane.

Abstract Every day, new applications arise relying on the use of high-resolution road maps in both academic and industrial environments. Autonomous vehicles rely on digital maps to navigate when optical sensors cannot be trusted, such as heavy rainfalls, snowy conditions, fog, and other situations. These situations increase the risks of accidents and disable the potentials of real-time mapping sensors. To tackle those problems, we present a methodology to automatically map anomalies on the road, namely speed bumps in this study, using an off-the-shelf camera (GoPro) and Machine Learning (ML) algorithms. We acquired data over a series of differently shaped speed bumps and applied three classification techniques: Naive Bayes, Multi-Layer Perceptron, and Random Forest (RF). With over 96% of classification accuracy, then RF was able to identify speed bumps on a GoPro dataset automatically. The results show a potential of the proposed methodology to be developed in surveying vehicles to produce highly-detailed maps of vertical road anomalies with a fast and accurate update rate.

Por el movimiento de pasmosa velocidad con que se transformó la vida europea en las primeras décadas del siglo xx, el historiador alemán Philipp Blom llamó a este tiempo “los años de vértigo”. Así se ha titulado también este libro, que puede leerse como una constancia de la experiencia intelectual y espiritual que tuvo en Europa, justo antes y durante la Primera Guerra Mundial, el ensayista antioqueño Baldomero Sanín Cano, quien había llegado a Londres en febrero de 1909, como enviado del gobierno de Rafael Reyes. Era la primera vez que Sanín Cano dejaba su país. Su experiencia de este tiempo es palpable a través de su participación en Hispania, una revista de cincuenta y cuatro números publicada en la capital inglesa entre el 1 de enero de 1912 y el 27 de junio de 1916. Para dar cuenta de la primera experiencia europea de Sanín Cano, el libro se divide en tres partes. La primera, “I. Revista Hispania: aspectos, trayectos e itinerarios de un impreso continental”, es un estudio preliminar escrito por Rafael Rubiano Muñoz y Juan Guillermo Gómez García. La segunda es una compilación de treinta y nueve de los sesenta y cuatro artículos que Sanín Cano publicó en Hispania, y la tercera reúne catorce de sus veintitrés reseñas sobre libros. No se incluye ninguna de sus cuatro cartas. De un total de noventa y una colaboraciones de Sanín Cano en esta revista, según hace la cuenta el compilador, que es Rafael Rubiano Muñoz, aquí se publican treinta y nueve.