A radiographic study of mandibular nutrient canals in patients with periodontal diseases

Nutrient canals are intra-osseous spaces or channels containing nerves and blood vessels. They are observed more frequently in the mandibular anterior region as radiolucent horizontal lines of varying widths, usually situated interproximally and inferiorly to the teeth. The aims of this investigation were to evaluate radiographically the presence of nutrient canals in 500 patients with periodontitis and 500 controls, to correlate their presence with severity of bone loss and trabecular bone pattern and to correlate the type of trabecular bone pattern to the age of the patient, bone loss and number of nutrient canals

Using the Triple Bottom Line to Select Sustainable Suppliers for a Major Oil and Gas Company

Companies have primarily been focusing on the financial bottom line i.e., on increasing profits by increasing revenues and reducing costs. With high energy usage and environmental change posing threats to the environment and business operations, companies are now considering sustainability. Since some global suppliers have low cost labor, Social well-being and human development has also emerged as major goals of a company performing global operations. Focusing on these three goals is termed the Triple Bottom Line (TBL). We study and explore the TBL benefits that could be realized by an oil and gas company by focusing on sustainable suppliers. A company with a global supply chain cannot be sustainable without sustainable suppliers. This thesis develops the business case for sustainable suppliers using the TBL and presents the benefits of integrating sustainable suppliers into the supply chain. We consider a major oil and gas company and use multi-objective decision analysis to perform the analysis

Representation learning for neural population activity with Neural Data Transformers

Neural population activity is theorized to reflect an underlying dynamical structure. This structure can be accurately captured using state space models with explicit dynamics, such as those based on recurrent neural networks (RNNs). However, using recurrence to explicitly model dynamics necessitates sequential processing of data, slowing real-time applications such as brain-computer interfaces. Here we introduce the Neural Data Transformer (NDT), a non-recurrent alternative. We test the NDT's ability to capture autonomous dynamical systems by applying it to synthetic datasets with known dynamics and data from monkey motor cortex during a reaching task well-modeled by RNNs. The NDT models these datasets as well as state-of-the-art recurrent models. Further, its non-recurrence enables 3.9ms inference, well within the loop time of real-time applications and more than 6 times faster than recurrent baselines on the monkey reaching dataset. These results suggest that an explicit dynamics model is not necessary to model autonomous neural population dynamics. Code: https://github.com/snel-repo/neural-data-transformer

lfads-torch: A modular and extensible implementation of latent factor analysis via dynamical systems

Latent factor analysis via dynamical systems (LFADS) is an RNN-based variational sequential autoencoder that achieves state-of-the-art performance in denoising high-dimensional neural activity for downstream applications in science and engineering. Recently introduced variants and extensions continue to demonstrate the applicability of the architecture to a wide variety of problems in neuroscience. Since the development of the original implementation of LFADS, new technologies have emerged that use dynamic computation graphs, minimize boilerplate code, compose model configuration files, and simplify large-scale training. Building on these modern Python libraries, we introduce lfads-torch -- a new open-source implementation of LFADS that unifies existing variants and is designed to be easier to understand, configure, and extend. Documentation, source code, and issue tracking are available at https://github.com/arsedler9/lfads-torch .Comment: 4 pages, 1 figure, 1 tabl

Ewing’s sarcoma of the mandible: A case report

Ewing’s sarcoma of the jaw is a primitive malignant tumor of the bone. It is commonly seen in children and adolescents. Its occurrence in the head and neck region is unusual and generally involves most frequently the mandible rather than the maxilla. The present case discuss the clinical, diagnostic (radiographic, histopathologic) and therapeutic findings of an ES of the mandible in a 14-year-old boy. Early detection of such lesions is difficult because the signs and the symptoms do not appear until the lesion has progressed considerably. This case elucidates the importance of professional knowledge of the relevant aspects of malignant lesions such as Ewing’s sarcoma

Geoquímica en México

Geochemistry in Mexic

A positive 'amount effect' in the Sahayadri (Western Ghats) rainfall

We present stable oxygen isotopic ratios (δ18O) of rainfall collected over three years (July to October 2000- 02) at Mangalore. We observe an apparent positive correlation between the monthly, amount-weighted mean oxygen isotopic ratio of the rainwater and monthly total rainfall, contrary to the generally expected negative trend in many island and continental stations. We offer an explanation for this observation and propose that the 'amount effect' in the annual rainfall still remains with a negative slope, and thus can be useful in palaeomonsoon reconstruction using oxygen isotopic variations of annually laminated speleothems

Evaluation of the odd-even effect in limits of detection for electron microprobe analysis of natural minerals

Limit of detection (LOD), being a fundamental quality parameter for analytical techniques, has been recently investigated and a systematic behavior has been observed for most odd–even element pairs for many techniques. However, to the best of our knowledge very few LOD data are available in published literature for electron microprobe analysis; these consist of three papers, two being on rare-earth elements and the third covering a large number of elements of atomic number between 21 and 92. These data confirm the systematic behavior of LODs for many odd–even pairs. To initiate to full this gap, we determined LODs for several major rock-forming chemical elements from Na to Fe with atomic numbers between 11 and 26, during the microprobe analysis of common minerals (olivine, plagioclase, pyroxene, amphibole, quartz, and opaques) in volcanic rocks. The odd–even effect of nuclear stability seems to be present in LOD data for most odd–even pairs investigated. Nevertheless, the experimental strategy concerning the reference materials, calibration procedure, and blank measurements, should be substantially modified to better evaluate the systematic behavior of LOD values in microprobe analysis