gebhart/patrepeval huggingface dataset:
Flexible <i>C</i><sub>2</sub>-Symmetric Bis-Sulfoxides as Ligands in Enantioselective 1,4-Addition of Boronic Acids to Electron-Deficient Alkenes (2013)

The application of acyclic C2-symmetric chelating bis-sulfoxide ligands in the Rh(I)-catalyzed enantioselective 1,4-addition of boronic acids to electron-deficient alkenes is reported. Among the acyclic ethane-bridged bis-sulfoxides tested, the ligand Ferbisox (11), bearing ferrocenyl moieties as substituents at the sulfinyl sulfurs, has exhibited the best results in terms of chemical yield (up to 96%) and enantioselectivity (up to 97% ee). The conjugate addition takes place smoothly in toluene at room temperature in short reaction times (typically 2 h). The reaction scope, including the use of different boronic acids, five-, six-, and seven-membered cyclic enones, an unsaturated lactone, and the most challenging acyclic ketones, is reported. An X-ray diffraction study of the [Ferbisox·RhCl]2 precatalyst clearly exhibits a dimeric structure with an S coordination of the sulfoxide to rhodium. On the basis of the X-ray data and on structural studies conducted in solution by (1)H NMR, a model explaining the high enantioselection observed is proposed.
Sorting the Heated Mess: Screening Tulip Cultivars for Sensitivity to Heat (2004)

Tulip bulbs are produced in the Netherlands and are shipped to United States during the months of July and August in temperature-controlled shipping containers. Each shipment is often composed of a mixture of many cultivars. Mechanical failure of temperature controls may result in high temperatures that ultimately may reduce forcing quality of the bulbs. When such accidents occur, an immediate decision must be made about whether to invest more time and money on these potentially damaged bulbs. Such a decision is not easy because symptoms of heat damage are often delayed until months later. Research on a single cultivar, `Apeldoorn', has shown that heat stress can cause flower abortion and other abnormalities. However, cultivars undoubtedly vary in their response to heat stress. Thus in the 2002 and 2004 forcing seasons, ≈45 cultivars were screened for response to a standard heat stress of 4 days at 35 °C. Prior to the heat stress, bulbs were held at 17 °C or 9 °C for 4 weeks, mimicking conditions used for late and early forced bulbs, respectively. Flower and leaf height, percent flower abortion, and flowering date were evaluated. Heat stress caused flower abortion and reduced plant height in sensitive cultivars. Across all cultivars, cold storage prior to the heat stress significantly increased bulb's sensitivity to heat stress. Using percent flower abortion, cultivars were grouped into three categories: resistant, moderate, and susceptible. With this information, we hope that damage assessment may become easier and fewer bulbs wasted.
A CORDIC Arithmetic Processor Chip (1980)

A monolithic processor computes products, quotients, and several common transcendental functions. The algorithms are based on the well-known principles of "CORDIC," but recourse to a subtle novel corollary results in a scale factor of unity. Compared to older machines, the overhead burden is significantly reduced. Also, expansion of the functional repertoire beyond the circular domain, i.e., addition to the menu of hyperbolic and linear operations, is a relatively trivial matter, in terms of both hardware cost and execution time. A bulk CMOS technology with conservative layout rules is used for the sake of high reliability, low-power consumption, and good cycle speed.
An energy harvesting system for passively generating power from human activities (2013)

This paper presents a complete, self-contained energy harvesting system composed of a magnetic energy harvester, an input-powered interface circuit and a rechargeable battery. The system converts motion from daily human activities such as walking, jogging, and cycling into usable electrical energy. By using an input-powered interface circuit, the system requires no external power supplies and features zero standby power when the input motion is too small for successful energy reclamation. When attached to a person's ankle during walking, the 100 cm3 system prototype is shown to charge a 3.7 V, 65 mAh lithium-ion polymer battery at an average power of 300 µW. The design and testing of the system under other operating conditions are presented herein.
The candidate oncogene <i>ZNF217</i> is frequently amplified in colon cancer (2004)

In this study we have defined the changes in gene copy number of the candidate oncogene ZNF217 during colon cancer development and progression. This gene is mapped to chromosome 20q and lies within 20q13.2, a region which we have previously shown to be highly amplified in colorectal cancer by comparative genomic hybridization. The gene copy number of ZNF217 was assessed in 100 colon carcinomas (19 Dukes' A, 42 Dukes' B and 39 Dukes' C), 13 colonic adenomas and 10 normal colon samples. DNA extracted from laser microdissected cells was amplified by multiplex real-time PCR at two distinct gene loci--ZNF217 and beta-globin (control gene)--on an ABI7700 sequence detection system. Of the 100 colon cancers studied, 61 showed some level of amplification of ZNF217, 15 had loss of ZNF217, while 24 were diploid. All the adenomas except one were diploid. In this study we have found that ZNF217 amplification is a frequent event in colon cancer and that the extent of its amplification varies markedly between tumours (range 3-13 copies). There was a trend toward poorer survival in patients whose cancers had either gain or loss of ZNF217.
An Automated, Observations-Based System for Short-Term Prediction of Ceiling and Visibility (1997)

Several methods of generating very short term (0–6 h) probabilistic forecasts of ceiling and visibility are investigated: 1) an observations-based (OBS-based) system in which potential predictors consist of weather observations from a network of surface stations along with several climatic terms; 2) the traditional model output statistics (MOS)-based approach in which potential predictors consist of nested grid model (NGM) output, the latest observation from the forecast site, and climatic variables; and 3) persistence climatology in which potential predictors consist of the latest observation of the predictand variable from the forecast site and several climatic terms. Forecasts are generated for each technique on 2 yr (1993–94) of independent data for 25 stations in the eastern United States. Two variables (ceiling and visibility) are forecasted for eight thresholds, two initial times (0300 and 1500 UTC), and three lead times (1, 3, and 6 h). Results show that the OBS-based method is superior to persistence climatology at all lead times and all variable thresholds. This is encouraging since persistence climatology is widely recognized as a formidable benchmark for very short range prediction of ceiling and visibility. Verifications also show that the OBS-based system outperforms the traditional MOS-based technique at the 1- and 3-h lead times with skill improvements of four percentage points. Based upon historical values of improvements in skill, this gain corresponds to roughly a half decade of scientific advancement. Performance of the OBS- and MOS-based systems are similar at the 6-h projection, which appears to be near the crossover point when the NGM guidance becomes more important than the observations in terms of predictive input. These findings indicate that traditional MOS-based techniques for the very short term prediction of aviation weather parameters can be improved significantly by considering information from a network of surface observations. Furthermore, the improvements of the OBS-based system over the MOS-based method represent the minimum that can be expected since the test comparison of the two methods was intentionally constructed to maximize the performance of the MOS-based procedure. Still further, forecasts from an OBS-based system can be available within seconds of receiving the observations. Therefore, OBS-based systems are likely to be of far greater utility for making very short term forecasts than other traditional forms of guidance.
Neighbor discovery in mobile ad hoc self-configuring networks with directional antennas: algorithms and comparisons (2008)

In this paper, we consider the neighbor discovery problem in wireless ad hoc networks with directional antennas. One key performance measure is how long it takes to discover all the neighbors given that nodes do not have priori knowledge where their neighbors are. One common impression is that algorithms using directional transmission/receive take longer time than those algorithms using omni-antennas. In this paper, we prove that this is not the case. Furthermore, most of the proposed algorithms are 1-way only, which is not suitable for networks with directional antennas. We first propose three 2-way random neighbor discovery algorithms (based on the algorithms in [Vasuden et al., 2005]), two of which may still use omni-antennas in certain stages of the algorithms and a new scan based algorithm. Then we derive analytical expressions for the average number of slots required to discover all the neighbors for the three 2-way random algorithms and for two scan based algorithms. Analytic and simulation results are presented to compare 4 of the algorithms. From the numerical results, we conclude that scan-based all-directional algorithms give the best performance among all the algorithms considered. If designed properly, all-directional algorithms can discover neighbors in less time than those algorithms using omni-directional antennas.
BCL10 gene mutation in lymphoma (2000)

BCL10 is directly involved in t(1;14)(p22;q32) of mucosa-associated lymphoid tissue (MALT) lymphoma. Wild-type BCL10 promoted apoptosis and suppressed malignant transformation in vitro, whereas truncated mutants lost the pro-apoptotic activity and exhibited gain of function enhancement of transformation. We studied 220 lymphomas for genomic BCL10 mutation by polymerase chain reaction–single-strand conformational polymorphism and DNA sequencing. Nineteen mutations were found in 13 lymphoma specimens, as follows: 8 of 120 (6.7%) mucosa-associated lymphoid tissue (MALT) lymphomas, 4 of 42 (9.5%) follicular lymphomas, and 1 of 23 (4.3%) diffuse large B-cell lymphomas. No mutations were found in 14 mantle cell lymphomas or 21 T-cell lymphomas. High-grade MALT lymphoma tended to show a slightly higher mutation frequency (2 of 25, 8%) than low-grade MALT tumor (6 of 95, 6.3%). Among low-grade gastric MALT lymphoma, mutations were found in 3 of 11 tumors that did not respond to Helicobacter pylori eradication therapy, but none were found in 22 tumors that regressed completely after H pylori eradication. All 14 potentially pathogenic mutations were distributed in the carboxyl terminal domain of BCL10. Deletion accounted for 10 of these mutations; 10 of 14 mutations caused truncated forms of BCL10. Western blot analysis of a mutant case confirmed the presence of truncated BCL10 products of anticipated size. Our results suggest that BCL10 mutation may play a pathogenic role in B-cell lymphoma development, particularly in aggressive and antibiotic unresponsive MALT lymphomas, and may further implicate the biologic importance of the carboxyl terminal of the molecule.
Performance of Packaged Piezoelectric Microspeakers Depending on the Material Properties (2009)

This paper presents the improved piezoelectric microspeakers that implement a packaging structure with AlN film and are made of composite diaphragms of different residual stresses. The output Sound Pressure Level (SPL) is enhanced more than 10 dB with a higher compressively stressed composite diaphragm (having -20 MPa silicon nitride film as a supporting layer) from 100 Hz to 3 kHz. The best microspeaker produces more than 100 dB SPL into open field around 3 kHz (when measured 10 mm away from the speaker that is driven with 20 V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">peak-to-peak</sub> sinusoidal signal). A microspeaker with a square electrode pattern produces more uniform frequency response above 4 kHz than that with a circular electrode pattern.
Vapour transport growth of ZnO nanowires using a predeposited nanocrystalline template (2006)

Vapour transport growth of ZnO nanowires has been reported by a few groups. In most of the vapour transport deposition processes, 1-D ZnO nanostructures were produced at relatively high temperature (>900°C) and a pre-deposited catalyst, such as Au, Co, or Sn, was needed to supply nucleation sites and provide the function of growth direction confinement. Here we have produced single crystal ZnO nanowires using a modified vapour transport method, in which a nanocrystalline ZnO template layer was first deposited by ultrasonic spray assisted chemical vapour deposition. The pre-deposited template was then used to grow ZnO nanowires by a traditional vapour deposition method. The nanowires were characterised using X-ray diffraction, field-emission gun scanning electron microscopy (FEG-SEM) and highresolution transmission electron microscopy (HRTEM). Several different morphologies of the ZnO nanowires, including branched wire growth, were observed and a possible growth mechanism was discussed.
Priming of human mitochondrial DNA replication occurs at the light-strand promoter. (1985)

Individual promoters for transcription of each strand of human mtDNA are located near the origin of heavy-strand DNA replication in the displacement-loop region. Initiation of heavy-strand synthesis represents the first event in mtDNA replication. Analyses of the 5' and 3' map positions of displacement-loop nucleic acids from mitochondria of cultured human cells reveal a close correspondence between the 3' ends of RNA, whose 5' ends map at a unique site, and the 5' ends of DNA strands. The 5' ends of the RNA species all map at nucleotide position 407 in the genomic sequence, which corresponds exactly to the major 5' transcriptional start site, determined previously in vitro, that is contained within the light-strand promoter sequence. Displacement-loop heavy-strand DNAs map immediately adjacent to the 3' termini of these RNAs, and these transition points between RNA and DNA lie within short conserved sequence blocks in the template sequence. The simplest interpretation of these data is that replication is initiated at the major transcriptional promoter with subsequent precise cleavage of primary transcripts to provide the appropriate primer species.
Regulation of fatty acid composition in Escherichia coli: a proposed common mechanism for changes induced by ethanol, chaotropic agents, and a reduction of growth temperature (1982)

Growth of Escherichia coli in the presence of ethanol and chaotropic salts resulted in the synthesis of lipids containing elevated levels of unsaturated fatty acids analogous to the effect of a reduction in growth temperature. Both ethanol and chaotropic agents acted at the level of fatty acid biosynthesis and altered lipid composition by decreasing the proportion of saturated acyl chains available for the synthesis of phospholipids. A reduction in temperature causes similar effects on fatty acid biosynthesis in vivo and in vitro. Ethanol, chaotropic salts, and a decrease in temperature all weaken hydrophobic interactions. Antichaotropic salts antagonized and effects of these treatments on fatty acid synthesis in vitro. These results are consistent with a common mechanism for the effects of chaotropic agents, temperature, and ethanol on fatty acid synthesis. The biosynthesis of saturated and unsaturated acyl chains may be regulated by the strength of hydrophobic interactions. Changes in the strength of hydrophobic interactions could alter enzyme structure, substrate structure, or the equilibrium between the soluble enzymes of fatty acid synthesis and their respective acyl carrier protein substrates.
A Telecom Perspective on the Internet of Drones: From LTE-Advanced to 5G (2018)

Drones are driving numerous and evolving use cases, and creating transformative socio-economic benefits. Drone operation needs wireless connectivity for communication between drones and ground control systems, among drones, and between drones and air traffic management systems. Mobile networks are well positioned to identify, track, and control the growing fleet of drones. The wide-area, quality, and secure connectivity provided by mobile networks can enhance the efficiency and effectiveness of drone operations beyond visual line-of-sight range. In this article, we elaborate how the drone ecosystem can benefit from mobile technologies, summarize key capabilities required by drone applications, and analyze the service requirements on mobile networks. We present field trial results collected in LTE-Advanced networks to gain insights into the capabilities of the current 4G+ networks for connected drones and share our vision on how 5G networks can further support diversified drone applications.
Modulation of complement activation on hemodialysis membranes by immobilized heparin. (1992)

To determine the effects of surface-associated heparin on the capacity of hemodialysis membranes to activate complement, cellulose acetate (CA) membranes that were untreated and CA membranes that had been coated with heparin (HCA) were incubated with C3-depleted serum repleted with radio-labeled C3. Next, the proteins in the supernatant and those eluted from the membranes were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. C3 activation was quantified by determining the radioactivity of the C3a-containing band in the gel. Total C3a generation (fluid phase C3a plus membrane-associated C3a) was three times greater in the presence of HCA compared with CA. Most (88%) of the C3a generated in the presence of HCA, however, was adsorbed onto the membrane surface. Consequently, there was more C3a in the CA supernatant than in the HCA supernatant. To determine the mechanism by which heparin enhanced alternative pathway activity, binding studies with radiolabeled factor B and factor H were performed. HCA bound 3.4 times more factor B and 20 times more factor H than did CA. The binding of these proteins, however, was not dependent on complement activation. Studies designed to test the functional activity of isolated factor H and factor B that had been adsorbed to the membrane showed that factor H was active on both CA and HCA, whereas factor B was active only on HCA. These data demonstrate that heparin immobilized onto CA hemodialysis membrane enhances C3 activation but produces low levels of C3a in the fluid phase because of high surface adsorption of the anaphylatoxin. Heparin appears to augment alternative pathway activity by favoring the interactions of factor B with other constituents of the amplification C3 convertase of the alternative pathway of complement.
Genetic changes in methotrexate‐resistant mosquito cells (1990)

Abstract A stepwise selection procedure was used to obtain from Mtx‐5011 Aedes albopictus cells, variants with increased resistance to methotrexate (mtx). On the basis of growth, the Mtx‐5011 derivatives were 270‐ to 3,000‐fold more resistant to mtx than wild‐type mosquito cells. Properties associated with mtx resistance in these cells were consistent with amplification of the dihydrofolate reductase (DHFR) gene. The cells overproduced DHFR protein, were enriched with DHFR mRNA, and DNA from resistant cells was enriched for a band that likely contained the DHFR coding sequence. Karyotype analysis indicated that high levels of resistance were accompanied by a conversion to tetraploidy, chromosome rearrangements, and an apparent duplication of one of the mosquito chromosomes.
Phylogenetic Analysis of <i>Salmonella</i> , <i>Shigella</i> , and <i>Escherichia coli</i> Strains on the Basis of the <i>gyrB</i> Gene Sequence (2002)

Phylogenetic analysis of about 200 strains of Salmonella, Shigella, and Escherichia coli was carried out using the nucleotide sequence of the gene for DNA gyrase B (gyrB), which was determined by directly sequencing PCR fragments. The results establish a new phylogenetic tree for the classification of Salmonella, Shigella, and Escherichia coli in which Salmonella forms a cluster separate from but closely related to Shigella and E. coli. In comparison with 16S rRNA analysis, the gyrB sequences indicated a greater evolutionary divergence for the bacteria. Thus, in screening for the presence of bacteria, the gyrB gene might be a useful tool for differentiating between closely related species of bacteria such as Shigella spp. and E. coli. At present, 16S rRNA sequence analysis is an accurate and rapid method for identifying most unknown bacteria to the genus level because the highly conserved 16S rRNA region is easy to amplify; however, analysis of the more variable gyrB sequence region can identify unknown bacteria to the species level. In summary, we have shown that gyrB sequence analysis is a useful alternative to 16S rRNA analysis for constructing the phylogenetic relationships of bacteria, in particular for the classification of closely related bacterial species.
Genetic epidemiology of single-nucleotide polymorphisms (1999)

On the causal hypothesis, most genetic determinants of disease are single-nucleotide polymorphisms (SNPs) that are likely to be selected as markers for positional cloning. On the proximity hypothesis, most disease determinants will not be included among markers but may be detected through linkage disequilibrium with other SNPs. In that event, allelic association among SNPs is an essential factor in positional cloning. Recent simulation based on monotonic population expansion suggests that useful association does not usually extend beyond 3 kb. This is contradicted by significant disequilibrium at much greater distances, with corresponding reduction in the number of SNPs required for a cost-effective genome scan. A plausible explanation is that cyclical expansions follow population bottlenecks that establish new disequilibria. Data on more than 1,000 locus pairs indicate that most disequilibria trace to the Neolithic, with no apparent difference between haplotypes that are random or selected through a major disease gene. Short duration may be characteristic of alleles contributing to disease susceptibility and haplotypes characteristic of particular ethnic groups. Alleles that are highly polymorphic in all ethnic groups may be older, neutral, or advantageous, in weak disequilibrium with nearby markers, and therefore less useful for positional cloning of disease genes. Significant disequilibrium at large distance makes the number of suitably chosen SNPs required for genome screening as small as 30,000, or 1 per 100 kb, with greater density (including less common SNPs) reserved for candidate regions.
Diamond epitaxy on (001) silicon: An interface investigation (1995)

In combination with scanning electron microscopy and x-ray pole-figure analysis high resolution electron microscope (HREM) observation of the diamond-silicon cross section in a 〈001〉 epitaxially oriented diamond film was carried out to investigate the atomic interfacial microstructure. The films were prepared by microwave plasma chemical vapor deposition using a bias-enhanced nucleation technique. Due to the multiple fit of diamond and silicon lattices, there is a periodic 3-to-2 registry of {111} atom planes of the epitaxial diamond-silicon interface. Planar defects on diamond {111} planes and interface misfit dislocations are shown for epitaxially oriented and for slightly misoriented diamond crystallites. A cubic silicon carbide ‘‘transition’’ is found to be unnecessary for the epitaxy. The misorientation of the grown crystallites is also studied and found to be probably due to interface imperfection.