15 research outputs found
The Open DAC 2023 Dataset and Challenges for Sorbent Discovery in Direct Air Capture
New methods for carbon dioxide removal are urgently needed to combat global
climate change. Direct air capture (DAC) is an emerging technology to capture
carbon dioxide directly from ambient air. Metal-organic frameworks (MOFs) have
been widely studied as potentially customizable adsorbents for DAC. However,
discovering promising MOF sorbents for DAC is challenging because of the vast
chemical space to explore and the need to understand materials as functions of
humidity and temperature. We explore a computational approach benefiting from
recent innovations in machine learning (ML) and present a dataset named Open
DAC 2023 (ODAC23) consisting of more than 38M density functional theory (DFT)
calculations on more than 8,400 MOF materials containing adsorbed and/or
. ODAC23 is by far the largest dataset of MOF adsorption calculations at
the DFT level of accuracy currently available. In addition to probing
properties of adsorbed molecules, the dataset is a rich source of information
on structural relaxation of MOFs, which will be useful in many contexts beyond
specific applications for DAC. A large number of MOFs with promising properties
for DAC are identified directly in ODAC23. We also trained state-of-the-art ML
models on this dataset to approximate calculations at the DFT level. This
open-source dataset and our initial ML models will provide an important
baseline for future efforts to identify MOFs for a wide range of applications,
including DAC
Modifications of T-Scores by Quantitative Ultrasonography for the Diagnosis of Osteoporosis in Koreans
To identify a proper T-score threshold for the diagnosis of osteoporosis in Koreans using quantitative ultrasonography (QUS), normative data from 240 females and 238 males (ages 20-29 yr) were newly generated. Then, the osteoporosis prevalence estimate for men and women over 50 yr of age was analyzed using previous World Health Organization (WHO) methods and heel QUS. T-scores were calculated from the normative data. There were definite negative correlations between age and all of the QUS parameters, such as speed of sound (SOS), broadband ultrasound attenuation (BUA), and estimated heel bone mineral density (BMD) (p<0.0001). After applying the recently determined prevalence of incident vertebral fracture in Koreans over 50 yr of age (11.6% and 9.1%, female vs male, respectively) to the diagnosis of osteoporosis by T-scores from heel BMD as measured by QUS, it was revealed that applicable T-scores for women and men were -2.25 and -1.85, respectively. These data suggest that simply using a T-score of -2.5, the classical WHO threshold for osteoporosis, underestimates the true prevalence when using peripheral QUS. Further prospective study of the power of QUS in predicting the absolute risk of fracture is needed
Cutoff Values of Surrogate Measures of Insulin Resistance for Metabolic Syndrome in Korean Non-diabetic Adults
We investigated the cutoff values of surrogate of insulin resistance for diagnosing metabolic syndrome in Korean adults. The data from 976 non-diabetic individuals (484 men and 492 women) aged 30-79 yr were analyzed. We determined the odds ratios for the prevalence of metabolic syndrome according to the quartiles of fasting insulin, homeostasis model for insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI) as independent variables, while adjusting for age, sex, and body mass index. The cutoff values of fasting insulin, HOMA-IR, and QUICKI were estimated by the areas under the receiver-operating characteristic (ROC) curves. The cutoff points for defining insulin resistance are a fasting insulin level of 12.94 ĀµU/mL, HOMA-IR=3.04 as the 75th percentile value, and QUICKI=0.32 as the 25th percentile value. Compared with the lowest quartile, the adjusted odds ratios for the prevalence of metabolic syndrome in the highest quartiles of fasting insulin, HOMA-IR, and QUICKI were 1.95 (1.26-3.01), 2.27 (1.45-3.56), and 2.27 (1.45-3.56), respectively. The respective cutoff values for fasting serum insulin, HOMA-IR, and QUICKI by ROC analysis were 10.57 ĀµU/mL (sensitivity 58.5%, specificity 66.8%), 2.34 (sensitivity 62.8%, specificity 65.7%), and 0.33 (sensitivity 61.2%, specificity 66.8%). Fasting insulin, HOMA-IR, and QUICKI can be used as surrogate measures of insulin resistance in Korean non-diabetic adults
Laxative and antioxidant effects of ramie (Boehmeria nivea L.) leaf extract in experimental constipated rats
Abstract Ramie leaf (Boehmeria nivea L.) is rich in cellulose, polyphenol compounds, vitamin C, and minerals. The leaves of this plant, which are used for medicinal purposes, have long been reported to have antiāinflammatory, antioxidant, anticolitis, and antidiabetic effects. We investigated the protective effects of ramie leaf ethanol extract (RLE) against loperamideāinduced constipation and oxidative stress in rats. Male SpragueāDawley rats were administered 200 or 400Ā mg/kg body weight of RLE (RLEL and RLEH groups) by gavage, while normal (NOR) and control (CON) rats received saline. Loperamide (4.0Ā mg/kg, twice per day) was injected subcutaneously to induce constipation in RLEL, RLEH, and CON groups. Total fecal number, wet weight, and water content decreased, while the total number of loperamideāinduced fecal pellets in the distal colon increased with administration of RLE in a doseādependent manner. Gastrointestinal transit time was more greatly reduced in RLEātreated groups than in the CON group. Serum total cholesterol (TC) level, as well as alanine aminotransferase (ALT) and alkaline phosphatase (ALP) activity, was significantly lower in both RLEL and RLEH groups compared with the CON group. Intestinal mucosa malondialdehyde (MDA) and hydrogen peroxide (H2O2) production decreased significantly in a doseādependent manner in the RLEātreated groups. Loperamide decreased the antioxidant enzyme activity, including that of superoxide dismutase (SOD) and glutathione peroxidase (GSHāPx), while RLE administration increased the antioxidant activity. These results suggest that RLE exerts potent laxative and antioxidant effects in model rats with loperamideāinduced constipation
Novel Mutation in Related to Brachydactyly Type E2 Initially Confused with Unclassical Pseudopseudohypoparathyroidism
BackgroundAutosomal-dominant brachydactyly type E is a congenital abnormality characterized by small hands and feet, which is a consequence of shortened metacarpals and metatarsals. We recently encountered a young gentleman exhibiting shortening of 4th and 5th fingers and toes. Initially, we suspected him having pseudopseudohypoparathyroidism (PPHP) because of normal biochemical parameters, including electrolyte, Ca, P, and parathyroid hormone (PTH) levels; however, his mother and maternal grandmother had the same conditions in their hands and feet. Furthermore, his mother showed normal biochemical parameters. To the best of our knowledge, PPHP is inherited via a mutated paternal allele, owing to the paternal imprinting of GNAS (guanine nucleotide binding protein, alpha stimulating) in the renal proximal tubule. Therefore, we decided to further analyze the genetic background in this family.MethodsWhole exome sequencing was performed using genomic DNA from the affected mother, son, and the unaffected father as a negative control.ResultsWe selected the intersection between 45,490 variants from the mother and 45,646 variants from the son and excluded 27,512 overlapping variants identified from the father. By excluding homogenous and compound heterozygous variants and removing all previously reported variants, 147 variants were identified to be shared by the mother and son. Variants that had least proximities among species were excluded and finally 23 variants remained.ConclusionAmong them, we identified a defect in parathyroid hormone like hormone (PTHLH), encoding the PTH-related protein, to be disease-causative. Herein, we report a family affected with brachydactyly type E2 caused by a novel PTHLH mutation, which was confused with PPHP with unclassical genetic penetrance
Chromism-Integrated Sensors and Devices for Visual Indicators
The bifunctionality of chromism-integrated sensors and devices has been highlighted because of their reversibility, fast response, and visual indication. For example, one of the representative chromism electrochromic materials exhibits optical modulation under ion insertion/extraction by applying a potential. This operation mechanism can be integrated with various sensors (pressure, strain, biomolecules, gas, etc.) and devices (energy conversion/storage systems) as visual indicators for user-friendly operation. In this review, recent advances in the field of chromism-integrated systems for visual indicators are categorized for various chromism-integrated sensors and devices. This review can provide insights for researchers working on chromism, sensors, or devices. The integrated chromic devices are evaluated in terms of coloration-bleach operation, cycling stability, and coloration efficiency. In addition, the existing challenges and prospects for chromism-integrated sensors and devices are summarized for further research
Text Mining MetalāOrganic Framework Papers
We have developed
a simple text mining algorithm that allows us
to identify surface area and pore volumes of metalāorganic
frameworks (MOFs) using manuscript html files as inputs. The algorithm
searches for common units (e.g., m<sup>2</sup>/g, cm<sup>3</sup>/g)
associated with these two quantities to facilitate the search. From
the sample set data of over 200 MOFs, the algorithm managed to identify
90% and 88.8% of the correct surface area and pore volume values.
Further application to a test set of randomly chosen MOF html files
yielded 73.2% and 85.1% accuracies for the two respective quantities.
Most of the errors stem from unorthodox sentence structures that made
it difficult to identify the correct data as well as bolded notations
of MOFs (e.g., <b>1a</b>) that made it difficult identify its
real name. These types of tools will become useful when it comes to
discovering structureāproperty relationships among MOFs as
well as collecting a large set of data for references