651 research outputs found
Nuclear reactor power as applied to a space-based radar mission
The SP-100 Project was established to develop and demonstrate feasibility of a space reactor power system (SRPS) at power levels of 10's of kilowatts to a megawatt. To help determine systems requirements for the SRPS, a mission and spacecraft were examined which utilize this power system for a space-based radar to observe moving objects. Aspects of the mission and spacecraft bearing on the power system were the primary objectives of this study; performance of the radar itself was not within the scope. The study was carried out by the Systems Design Audit Team of the SP-100 Project
Efektivitas Pemanfaatan Limbah Tahu Cair Melalui Metode Frekuensi Waktu Penyiraman terhadap Pertumbuhan Produksi Rumput Gajah (Pennisetum purpureum)
This research was conducted in the experimental garden of the Faculty of Agriculture, University of Timor, Sasi, North Central Timor Regency. The research will last for 1 production period (45 HST), from the end of March to the beginning of June 2019. The purpose of this study is to analyze the value of growth and production of Pennisetum purpureum treated with frequency of time watering liquid tofu waste. This research is an experimental study using a randomized design Complete (CRD) consisting of 4 treatments and 4 replications so that there are 16 units of the experimental unit. The treatments tested consisted of: R0 = Without watering tofu waste, R1 = Frequency of watering once every 2 days, R2 = Frequency of watering once every 4 days, R3 = Frequency of watering once every 6 days. The variables observed in this study were plant height, stem diameter, leaf fresh weight and leaf dry weight. The results showed that giving treatment of the frequency of time of watering the liquid tofu waste, had a significant effect on the fresh weight of leaves produced but did not differ on plant height of stem diameter and dry weight produced. It could be concluded that liquid tofu waste with good watering time frequency was found in the treatment R1 which is 2 days, liquid tofu waste has the ability to improve soil texture and can stimulate the growth of Pennisetum purpureum in this case the growth of plant height, stem diameter, leaf fresh weight, and leaf dry weight.Penelitian ini dilaksanakan di kebun percobaan Fakultas Pertanian, Universitas Timor, Kelurahan Sasi, Kecamatan Kota, Kabupaten Timor Tengah Utara. Penelitian berlangsung selama 1 periode produksi (45 HST) yaitu dari akhir Maret sampai awal juni 2019. Tujuan dari penelitian ini untuk menganalisis nilai pertumbuhan dan produksi rumput gajah yang diberi perlakuan frekuensi waktu penyiraman limbah tahu cair. Penelitian ini merupakan penelitian eksperimen menggunakan Rancangan Acak Lengkap (RAL) yang terdiri dari 4 perlakuan dan 4 ulangan sehingga terdapat 16 unit satuan percobaan. Perlakuan yang diuji terdiri dari: R0 = Tanpa penyiraman limbah tahu, R1=Frekuensi penyiraman 2 hari sekali, R2= Frekuensi penyiraman 4 hari sekali, R3= Frekuensi penyiraman 6 hari sekali. Variabel yang diamati dalam penelitian ini adalah tinggi tanaman, diameter batang, berat segar daun dan berat kering daun. Hasil penelitian menunjukkan bahwa pemberian perlakuan frekuensi waktu penyiraman limbah tahu cair, memberikan pengaruh yang nyata terhadap berat segar daun yang di hasilkan namun tidak berbeda terhadap tinggi tanaman diameter batang dan berat kering yang dihasilkan. Disimpulkan bahwa limbah tahu cair dengan frekuensi waktu penyiraman yang baik terdapat pada perlakuan R1 yaitu 2 hari sekali, limbah tahu cair memiliki kemampuan untuk memperbaiki tekstur tanah dan dapat merangsang pertumbuhan rumput gajah dalam hal ini pertumbuhan tinggi tanaman, diameter batang, berat segar daun, dan berat kering daun
2-(1,3-Benzoxazol-2-ylsulfanyl)-1-phenylethanone
In the title compound, C15H11NO2S, a new thio-benzoxazole derivative, the dihedral angle between the benzoxazole ring and the phenyl ring is 9.91 (9)°. An interesting feature of the crystal structure is the short C⋯S [3.4858 (17) Å] contact, which is shorter than the sum of the van der Waals radii of these atoms. In the crystal structure, molecules are linked together by zigzag intermolecular C—H⋯N interactions into a column along the a axis. The crystal structure is further stabilized by intermolecular π–π interactions [centroid–centroid = 3.8048 (10) Å]
Associations between breast cancer subtype and neighborhood socioeconomic and racial composition among Black and White women
PURPOSE: Studies of Black-White differences in breast cancer subtype often emphasize potential ancestry-associated genetic or lifestyle risk factors without fully considering how the social or economic implications of race in the U.S. may influence risk. We assess whether neighborhood racial composition and/or socioeconomic status are associated with odds of triple-negative breast cancer (TNBC) diagnosis relative to the less-aggressive hormone receptor-positive/HER2-negative subtype (HR+ /HER-), and whether the observed relationships vary across women\u27s race and age groups.
METHODS: We use multilevel generalized estimating equation models to evaluate odds of TNBC vs. HR+ /HER2- subtypes in a population-based cohort of 7291 Black and 74,208 White women diagnosed with breast cancer from 2006 to 2014. Final models include both neighborhood-level variables, adjusting for individual demographics and tumor characteristics.
RESULTS: Relative to the HR+ /HER- subtype, we found modestly lower odds of TNBC subtype among White women with higher neighborhood median household income (statistically significant within the 45-64 age group, OR = 0.981 per 10,000 increase; OR = 0.942 per 10% increase in Black residents).
CONCLUSION: The relationships between neighborhood composition, neighborhood socioeconomic status, and odds of TNBC differ by race and age. Racially patterned social factors warrant further exploration in breast cancer subtype disparities research
2-(1,3-Benzothiazol-2-ylsulfanyl)-1-phenylethanone
In the molecule of the title compound, C15H11NOS2, the 1,3-benzothiazole ring is oriented at a dihedral angle of 6.61 (6)° with respect to the phenyl ring. In the crystal structure, intermolecular C—H⋯O interactions link the molecules in a herring-bone arrangement along the b axis and π–π contacts between the thiazole and phenyl rings [centroid–centroid distance = 3.851 (1) Å] may further stabilize the structure
Ligand-Bound GeneSwitch Causes Developmental Aberrations in Drosophila that Are Alleviated by the Alternative Oxidase
Culture of Drosophila expressing the steroid-dependent GeneSwitch transcriptional activator under the control of the ubiquitous -tubulin promoter was found to produce extensive pupal lethality, as well as a range of dysmorphic adult phenotypes, in the presence of high concentrations of the inducing drug RU486. Prominent among these was cleft thorax, seen previously in flies bearing mutant alleles of the nuclear receptor Ultraspiracle and many other mutants, as well as notched wings, leg malformations, and bristle abnormalities. Neither the -tubulin-GeneSwitch driver nor the inducing drug on their own produced any of these effects. A second GeneSwitch driver, under the control of the daughterless promoter, which gave much lower and more tissue-restricted transgene expression, exhibited only mild bristle abnormalities in the presence of high levels of RU486. Coexpression of the alternative oxidase (AOX) from Ciona intestinalis produced a substantial shift in the developmental outcome toward a wild-type phenotype, which was dependent on the AOX expression level. Neither an enzymatically inactivated variant of AOX, nor GFP, or the alternative NADH dehydrogenase Ndi1 from yeast gave any such rescue. Users of the GeneSwitch system should be aware of the potential confounding effects of its application in developmental studies.Peer reviewe
Joanne Knight Breast Health Cohort at Siteman Cancer Center
PURPOSE: The Joanne Knight Breast Health Cohort was established to link breast cancer risk factors, mammographic breast density, benign breast biopsies and associated tissue markers, and blood markers in a diverse population of women undergoing routine mammographic screening to study risk factors and validate models for breast cancer risk prediction.
METHODS: Women were recruited from November 2008 to April 2012 through the mammography service at the Joanne Knight Breast Health Center at Washington University in St. Louis, Missouri. Baseline questionnaire risk factors, blood, and screening mammograms were collected from 12,153 women. Of these, 1,672 were excluded for prior history of any cancer (except non-melanoma skin) or diagnosis of breast cancer within 6 months of blood draw/registration for the study, for a total of 10,481 women. Follow-up is through linking to electronic health records, tumor registry, and death register. Routine screening mammograms are collected every 1-2 years and incident benign breast biopsies and cancers are identified through record linkage to pathology and tumor registries. Formal fixed tissue samples are retrieved and stored for analysis. County-level measures of structural inequality were derived from publicly available resources.
RESULTS: Cohort Composition: median age at entry was 54.8 years and 26.7% are African American. Through 2020, 74% of participants have had a medical center visit within the past year and 80% within the past 2 years representing an average of 9.7 person-years of follow-up from date of blood draw per participant. 9,997 women are continuing in follow-up. Data collected at baseline include breast cancer risk factors, plasma and white blood cells, and mammograms prior to baseline, at baseline, and during follow-up.
CONCLUSION: This cohort assembled and followed in a routine mammography screening and care setting that serves a diverse population of women in the St. Louis region now provides opportunities to integrate study of questionnaire measures, plasma and DNA markers, benign and malignant tissue markers, and repeated breast image features into prospective evaluation for breast cancer etiology and outcomes
2-(Benzo[d]thiazol-2-ylsulfonyl)-1-(4-bromophenyl)ethanone
In the title molecule, C15H10BrNO3S2, the dihedral angle between the benzothiazole ring system and the benzene ring is 67.57 (12)°. The crystal structure is stabilized by weak intermolecular C—H⋯O interactions. In addition, there is an intermolecular Br⋯C [3.379 (3) Å] contact which is shorter than the sum of the van der Waals radii of these atoms
Conformational effects on the Circular Dichroism of Human Carbonic Anhydrase II: a multilevel computational study
Circular Dichroism (CD) spectroscopy is a powerful method for investigating conformational changes in proteins and therefore has numerous applications in structural and molecular biology. Here a computational investigation of the CD spectrum of the Human Carbonic Anhydrase II (HCAII), with main focus on the near-UV CD spectra of the wild-type enzyme and it seven tryptophan mutant forms, is presented and compared to experimental studies. Multilevel computational methods (Molecular Dynamics, Semiempirical Quantum Mechanics, Time-Dependent Density Functional Theory) were applied in order to gain insight into the mechanisms of interaction between the aromatic chromophores within the protein environment and understand how the conformational flexibility of the protein influences these mechanisms. The analysis suggests that combining CD semi empirical calculations, crystal structures and molecular dynamics (MD) could help in achieving a better agreement between the computed and experimental protein spectra and provide some unique insight into the dynamic nature of the mechanisms of chromophore interactions
ATPase activity of DFCP1 controls selective autophagy
Cellular homeostasis is governed by removal of damaged organelles and protein aggregates by selective autophagy mediated by cargo adaptors such as p62/SQSTM1. Autophagosomes can assemble in specialized cup-shaped regions of the endoplasmic reticulum (ER) known as omegasomes, which are characterized by the presence of the ER protein DFCP1/ZFYVE1. The function of DFCP1 is unknown, as are the mechanisms of omegasome formation and constriction. Here, we demonstrate that DFCP1 is an ATPase that is activated by membrane binding and dimerizes in an ATP-dependent fashion. Whereas depletion of DFCP1 has a minor effect on bulk autophagic flux, DFCP1 is required to maintain the autophagic flux of p62 under both fed and starved conditions, and this is dependent on its ability to bind and hydrolyse ATP. While DFCP1 mutants defective in ATP binding or hydrolysis localize to forming omegasomes, these omegasomes fail to constrict properly in a size-dependent manner. Consequently, the release of nascent autophagosomes from large omegasomes is markedly delayed. While knockout of DFCP1 does not affect bulk autophagy, it inhibits selective autophagy, including aggrephagy, mitophagy and micronucleophagy. We conclude that DFCP1 mediates ATPase-driven constriction of large omegasomes to release autophagosomes for selective autophagy
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