Miracle-dz/UniFAR-FTUs huggingface dataset:
Rapid complementation assays measuring replicative potential of human immunodeficiency virus type 1 envelope glycoprotein mutants

Rapid assays which measure the ability of mutant human immunodeficiency virus type 1 envelope glycoproteins to mediate cell-free and/or cell-to-cell transmission of virus are described. By using these assays, envelope glycoprotein mutants with varying degrees of syncytium-forming ability were tested for ability to complement viral replication in trans. As expected, mutants that dramatically affect association of the gp120-gp41 envelope subunits, CD4 binding, or membrane fusion were unable to form syncytia or to support cell-free or cell-to-cell transmission. Surprisingly, some membrane fusion-defective mutants significantly attenuated in syncytium-forming ability were able to complement viral replication. Conversely, mutations in the carboxyl terminus of gp41 transmembrane glycoprotein, although not affecting syncytium-forming ability, significantly attenuated both forms of virus transmission. These results indicate that syncytium formation is not sufficient for cell-to-cell transmission of human immunodeficiency virus type 1. Furthermore, virus transmission appears to be less sensitive to inhibition of membrane fusion than is syncytium formation.
Improving Operational Performance of Magnetically Suspended Flywheel With PM-Biased Magnetic Bearings Using Adaptive Resonant Controller and Nonlinear Compensation Method

Permanent magnet-biased magnetic bearings (PBMBs) are widely used in flywheel energy storage systems because of their comprehensive advantage in power loss and controllability. However, there is a nonlinear relationship between magnetic force, control current, and eccentric displacement of the PBMB. When the system is required to be high performance, the nonlinear dynamics of the PBMB must be considered in a control design. Therefore, this paper proposes a novel nonlinear compensator based on the nonlinear model of the PBMB and it is applied to a magnetically suspended flywheel (MSF) with PBMBs. To implement the perfect nonlinear compensation, an adaptive resonant controller is also presented to compensate the dynamics of the current-mode amplifier. Finally, the proposed method is verified by experiments on the test rig of the MSF and can be used to improve the performance of the system.
Heteroduplex DNA correction in Saccharomyces cerevisiae is mismatch specific and requires functional PMS genes

In vitro-constructed heteroduplex DNAs with defined mismatches were corrected in Saccharomyces cerevisiae cells with efficiencies that were dependent on the mismatch. Single-nucleotide loops were repaired very efficiently; the base/base mismatches G/T, A/C, G/G, A/G, G/A, A/A, T/T, T/C, and C/T were repaired with a high to intermediate efficiency. The mismatch C/C and a 38-nucleotide loop were corrected with low efficiency. This substrate specificity pattern resembles that found in Escherichia coli and Streptococcus pneumoniae, suggesting an evolutionary relationship of DNA mismatch repair in pro- and eucaryotes. Repair of the listed mismatches was severely impaired in the putative S. cerevisiae DNA mismatch repair mutants pms1 and pms2. Low-efficiency repair also characterized pms3 strains, except that correction of single-nucleotide loops occurred with an efficiency close to that of PMS wild-type strains. A close correlation was found between the repair efficiencies determined in this study and the observed postmeiotic segregation frequencies of alleles with known DNA sequence. This suggests an involvement of DNA mismatch repair in recombination and gene conversion in S. cerevisiae.
Interacting Preferential Trade Agreements: Illustrations from Asia-Pacific

Multilateral trade negotiations have faced many hurdles and frustrations in recent years, giving increased impetus for some countries to negotiate regional and bilateral trade agreements. In this international climate, many countries are actively pursuing a range of bilateral trade agreements. However, gains from any bilateral trade agreement will be influenced not only by what is negotiated between the countries directly involved, but also by other preferential trade agreements that countries may negotiate with other countries. In this paper, we focus on some of the agreements that China is currently negotiating. Agreements are currently under negotiation with countries that include New Zealand and Australia and a framework agreement between China and ASEAN was signed in 2002. Thus we explore how such preferential trade agreements might impact on one another. We use the dynamic GTAP model to assess the anticipated impact of possible liberalization scenarios, including analysis of how agreements with other countries may impact these gains. For example, while the China-New Zealand agreement is unlikely to have a large economic impact on China, significant gains may accrue to New Zealand, particularly if there is liberalization of the sensitive agricultural sector. However, if China also enters into preferential agreements with other countries, this is likely to adversely impact on the gains accruing to New Zealand. If the spokes emanating from the China hub can be joined in a regional free trade area, rather than bilateral hub-and-spoke agreements, the overall gains can be much greater.
RCN4GSC Meeting Report: Initiating a Testbed for Managing Data at the Interface of Biodiversity and Genomics/Metagenomics, May 2011

Following up on efforts from two earlier workshops, a meeting was convened in San Diego to (a) establish working connections between experts in the use of the Darwin Core and the GSC MIxS standards, (b) conduct mutual briefings to promote knowledge exchange and to increase the understanding of the two communities’ approaches, constraints, community goals, subtleties, etc., (c) perform an element-by-element comparison of the two standards, assessing the compatibility and complementarity of the two approaches, (d) propose and consider possible use cases and test beds in which a joint annotation approach might be tried, to useful scientific effect, and (e) propose additional action items necessary to continue the development of this joint effort. Several focused working teams were identified to continue the work after the meeting ended.
Transmission Power and Antenna Allocation for Energy-Efficient RF Energy Harvesting Networks with Massive MIMO

The optimum transmission strategy for maximizing energy efficiency (EE) of a multi-user massive multiple-input multiple-output (MIMO) system in radio frequency energy harvesting networks is investigated. We focus on dynamic time-switching (TS) antennas, to avoid the practical problems of power-splitting antennas, such as complex architectures, power loss and signal distortion when splitting the power of the received signal into power for information decoding (ID) and energy harvesting (EH). However, since a single TS antenna cannot serve ID and EH simultaneously, the MIMO system is considered in this paper. We thus formulate an EE optimization problem and propose an iterative algorithm as a tractable solution, including an antenna selection strategy to optimally switch each TS antenna between ID mode and EH mode using nonlinear fractional programming and the Lagrange dual method. Further, the problem is solved under practical constraints of maximum transmission power and outage probabilities for a minimum amount of harvested power and rate capacity for each user. Simulation results show that the proposed algorithm is more energy-efficient than that of baseline schemes, and demonstrates the trade-off between the required amount of harvested power and energy efficiency.
Transconjunctival Sutureless 25-Gauge Versus 20-Gauge Standard Vitrectomy: Correlation Between Corneal Topography and Ultrasound Biomicroscopy Measurements of Sclerotomy Sites

Purpose: To determine the correlation between corneal shape changes and ultrasound biomicroscopy (UBM) findings at the sclerotomy sites in conventional 20-gauge (G) pars plana vitrectomy (PPV) and 25-G transconjunctival sutureless vitrectomy (TSV) and to compare the effectiveness of the two surgical methods. Design: Prospective, comparative, observational case series. Methods: Sixty consecutive eyes (60 patients) undergoing primary 3-port PPV. Thirty eyes (30 patients, group 20-G) were treated with 20-G standard PPV and 30 eyes (30 patients, group 25-G) with 25-G TSV. We compared healing of the sclerotomy sites in the two groups. We determined the correlation between corneal shape changes (surgically induced astigmatism) measured by videokeratography and the durations of scleral healing cicatrization by UBM within each group. Results: UBM examination showed that the 20-G sclerotomy sites took about 8 weeks to heal, measured as complete opposition, whereas healing of the 25-G TSV sclerotomy was quite rapid, with complete scleral opposition in about 4 weeks. Corneal topography analysis showed, during the early postoperative period, a surgically induced steepening of the cornea in both groups (20 G, 3.08 ± 0.56 diopters and 25 G, 0.805 ± 0.61 diopters, P < 0.001, Mann-Whitney test), which then decreased gradually, recovering to the preoperative level within two months in group 20 G (P > 0.05) and 1 month in group 25 G (P > 0.05). We found a strong statistical correlation between the mean surgically induced keratometric astigmatism and the mean UBM measures of scleral healing (r = 0.99 for group 20 G and r = 0.97 for group 25 G). Conclusion: After PPV, astigmatic changes are especially significant in the early postoperative period in 20-G group; the 25-G TSV system results in faster reduction of surgically induced keratometric astigmatism because of rapid cicatrization of the sclerotomy sites.
[Can lung protective ventilation methods modify outcome?--A critical review].

A large body of experimental and clinical work leaves no room for doubt that mechanical ventilation can contribute to the progression of a lung disease or, in the worst case, produce acute pulmonary damage. The pathophysiological processes involved have been described as barotrauma, volutrauma, atelectrauma and biotrauma. In response, a socalled lung-protective ventilation strategy has been proposed, especially for patients with acute respiratory distress syndrome (ARDS). Such an approach seeks to apply limited airway pressures, small tidal volumes and appropriate levels of positive end-expiratory pressures even if, as a consequence, non-physiological gas exchange values (i.e. elevated PaCO2-levels) need to be tolerated. A recent large prospective randomized trial demonstrated reduced mortality rates using such a strategy. To support lung-protective ventilation in ARDS patients, an array of therapeutic measures has been proposed, including meticulous attention to fluid and transfusion management, prone position, extracorporeal membrane oxygenation (ECMO), inhalation of nitric oxide, implementation of spontaneous breathing, partial liquid ventilation and tracheal gas insufflation. Of these, only prone positioning has become part of routine clinical management, while ECMO is applied in selected cases only. Unfortunately, thus far, none of these measures has passed the litmus test of a randomized controlled trial. Recent large prospective observational studies, however, suggest that only an optimized concert of therapeutic interventions, but not a single measure alone, may improve the outcome of ARDS patients.
The effects of early childhood education on literacy scores using data from a new Brazilian assessment tool

The aim of this study was to identify the effects of early childhood education (ECE) on literacy scores of 2nd grade students in elementary school. To do that, the Provinha Brasil was administered in Sertaozinho-SP, in conjunction with a socioeconomic questionnaire. Despite external validity problems, the evaluation of the effects of ECE in one municipality is advantageous, as we can estimate the effects of one kind of treatment. Other studies ignore this fact. Often, they estimate an average effect of various treatments effects (not just one), as they use data from different municipalities where ECE programs have different levels of quality. The OLS and Propensity Score Matching results show that students who started school at the ages of 5, 4, and 3 years had literacy scores between 12.22 and 19.54 points higher than those who began school at the age of 6 years or later.
Thia- and selenaheterocycles by a four-component reaction using elemental sulfur and selenium

The course of the four-component reactions of (2-benzimidazolyl) acetonitrile, carbondisulfide, isothiocyanate, and sulfur and selenium, respectively, is quite different. Whereas in the case of sulfur a tetracyclic [1,3]thiazolo[4′,5′:4,5]pyrimido[1,6-a]benzimidazol-2(3H)-thione is formed, a zwitterionic 7-(benzimidazolium-2-yl)-[1,2]thiaselenolo[2,3-b][1,2,4]thiaselenazole-6-thiolate (an azaselenadithiapentalene) is the product in the case of selenium. The structures of the products have been established by X-ray crystallography, and reaction mechanisms for their formation are proposed.
Complex rotary codes revisited: a low-complexity high-performance decoding approach

In this paper, based on a belief-propagation decoding strategy, a class of generalized parity-check codes called complex rotary codes is investigated. It is shown that, by using iterative sum-product decoding, the complex rotary codes have a much lower decoding complexity than Turbo codes, but have almost the same performance for the high code rate and short frame case (frame length< 500 bits). It is also shown that the prime block size of complex rotary codes is essential to achieve better performance because of its uniform checking characteristic.
A User Interface for Exploiting Web Communities in Searching the Web

We have implemented a novel user interface for Internet search engines that allows users to visualize the graph neighborhoods of search results returned. When the required information is not in the returned result set, it is likely that there is a path from one or more of the returned documents to another document that has the required information. Our proposed interface allows exploring these paths. We performed experiments to measure user effectiveness in finding desired information with the proposed interface, and compared it with the effectiveness of users restricted to using a traditional interface for the same underlying search engine. Given equal time to perform a set of search tasks, on average, the users of our interface were able to find twice as many of the required documents as the users of the traditional interface. We also found that, on average, users of the proposed interface tried 31% fewer queries per search task.
The Effect of Firm Internal and External Characteristics on Risk Reporting Practices among Malaysian Listed Firms

This study examines the effect of firm internal and external characteristics on risk reporting practices among the Malaysian public listed firms. Specifically, this study focuses on three internal characteristics namely, duality of board leadership, the presence of stand-alone risk management committee, and length of CEO tenure and external characteristics namely, competition, debt governance and auditor quality on the risk reporting practices among the Malaysian public listed firms. Using, content analysis on 200 top public listed firms in Bursa Malaysia, this study shows that one of the external characteristics namely, debt governance significantly influence risk disclosure among the Malaysian public listed firms. This study however, shows that none of the internal characteristics influence risk disclosure among the Malaysian public listed firms. The finding of this study provide further understanding on the nature of risk disclosure of Malaysian public listed firms.
A High-Linearity Capacitance-to-Digital Converter Suppressing Charge Errors From Bottom-Plate Switches

A high-precision capacitance-to-digital converter (CDC) that is configurable to interface with unipolar or push-pull-type capacitive sensors is presented in this paper. In the conventional switched-capacitor CDC, it is well known that clock feedthroughs and charge injections from top-plate switches can be eliminated by a bottom-plate sampling scheme. However, those charge errors from the bottom-plate switches depend on the digital output and the varying value of the sensing capacitor itself. They will thus affect the overall CDC linearity. When the varying range of the sensing capacitor is wide, the nonlinearity becomes more pronounced. This paper proposes new switching and calibration schemes to reduce these non-idealities. A prototype of a second order CDC employing the proposed techniques in a 0.18 μm CMOS process achieves a 53.2 aF RMS resolution with a 1 ms conversion time. The proposed calibration technique improves the linearity of the CDC from 9.3 bits to 12.3 bits and from 10.1 bits to 13.3 bits in the unipolar and push-pull-type sensing modes, respectively, with a sensing capacitance varying from 0.5 to 3.5 pF. The CDC is also demonstrated with a real-life pressure sensor.
Analysis of a low-inductance packaging layout for Full-SiC power module embedding split damping

A novel low-inductance packaging layout for Full-SiC (Silicon Carbide) MOSFET (Metal Oxide Semiconductor Field Effect Transistor) Module with split damping capacitors embedding inside is proposed in this paper. The 3-Demision model of the optimized layout was built and analyzed with ANSYS Q3D. The total self-inductance of the single commutation loop is only 6.2nH. Additionally, 55V voltage spike over the semiconductor on the current rate of 6717A per microsecond and remarkable current sharing characteristic are observed by LTspice simulation based on the synchronous buck circuit. Two comparative 1.2KV, 40A prototypes based on regular wire-bond structure were fabricated to verify the low inductance layout design. Experimental result of double pulse test demonstrates the validity of the design. The ultra-fast switching speed can be achieved by using the proposed layout design.
Hypoxia and nitric oxide exposure promote apoptotic signaling in contractile pulmonary arterial smooth muscle but not in pulmonary epithelium

Neonatal pulmonary hypertension is characterized by hypoxia, abnormal vascular remodeling, and impaired alveolarization. Nitric oxide (NO) regulates cell replication and activation of apoptosis. Our objective was to examine cell phenotype‐specific effects of hypoxia and NO exposure on cumulative apoptotic signal in neonatal pulmonary epithelial cells and arterial smooth muscle.
Non-restricted measurement of walking distance

Vertical walking distance is discussed. The horizontal distance is estimated by using the three dimensional acceleration of the subject's toe. Considering the movement of the foot, it is assumed that only the pitch angle of the foot changes and that the velocity of the foot is never negative. A three dimensional accelerometer is fixed to the subject's toe and measures the acceleration during the swing phase of the foot. A piezoelectric gyro is used to estimate the angle of the foot and to calculate its horizontal acceleration. The horizontal distance is obtained by integrating the horizontal acceleration twice each step. The vertical distance is calculated by integrating the change of atmospheric pressure during ascent or descent. A band pass filter is applied to reject natural changes of the atmospheric pressure and sensor noise. The integration of the output of the filter produces a value corresponding to the vertical distance. Experiments were performed in a horizontal corridor and on some stairs. The results show that the error of the horizontal distance estimated is less than 5.3% and 0.0% on average, and the vertical distance is less than 11.1%.
Spatial vision and aging. I: Contrast sensitivity.

Contrast sensitivity functions (CSFs) were measured for two groups of healthy observers, a younger group with mean age 18.5 years and an older group with mean age 73 years. Although the two groups had virtually identical sensitivities to high spatial frequencies (gratings with narrow bars), the younger observers were three times more sensitive at low and intermediate spatial frequencies (gratings with wider bars) than were the older observers. Groups did not differ in relative sensitivity to gratings flickered at two rates, . 33 and 6 Hz. The reduced sensitivity of older observers to low spatial frequencies cannot be explained in terms of optical factors or as the result of ocular pathology; it probably reflects a loss in that visual sub-system responsible for detecting low spatial frequency, temporally transient targets.
Mathematical Model of Large Rectenna Arrays for Wireless Energy Transfer

A mathematical model of a large rectenna array (LRA) is presented. It is shown that matrices describing the LRA linear subsystem have a number of specific features that must be considered when the rectenna mathematical model is developed. The state equation for the LRA was obtained. It is shown that the model functioning in nonlinear mode of the infinite rectenna array can be reduced to the parameters of one equivalent receiver-rectifier element (RRE) at the fundamental frequency and its harmonic. The external parameters of RREs and characteristics of LRAs were obtained.
Mapping the Signal Sequence-binding Site on SRP Reveals a Significant Role for the NG Domain*

We present evidence that the signal recognition particle (SRP) recognizes signal sequences via the NG domain on the SRP54 protein subunit. Using a recently developed cross-linking method (Fancy, D. A., and Kodadek, T. (1999)Proc. Natl. Acad. Sci. U. S. A. 96, 6020–6024; Correction (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 1317), we find that signal peptides cross-link to theEscherichia coli SRP protein Ffh (the homologue of the mammalian SRP54 subunit) via the NG domain. Within the NG domain, the cross-linking site maps to the ras-like C-terminal subdomain termed the G domain. This result stands in contrast to previous studies, which concluded based on nascent chain cross-linking that the signal sequence bound to the adjacent M domain. As independent evidence of a direct binding interaction between the NG domain and the signal sequence, we find that the NG domain of Ffh binds signal peptides as an isolated entity. Our results suggest that the NG domain forms a substantial part of the binding site for the signal sequence.
The Ratchet E ¤ ect : A Learning Perspective

We examine the ratchet e¤ect arising from moral hazard and symmetric learning about a new technology. A principal and agent are symmetrically uncertain about the di¢ culty of a new job. If the agent shirks, this increases his future payo¤s since the principal will, on average, believe that the job is harder than it actually is. So shirking must be deterred by high-powered incentives. These induce the agent to over-work, since he can quit if the principal believes that the job is easy. With continuous e¤ort choices, no interior e¤ort is implementable. We show that this problem is endemic in learning models where the agent has discrete as well as continuous choices. Rent-sharing, where the principal pays more than the outside option, can restore implementability, since the agent loses rents if he over-works. The ratchet e¤ect is strongest when the marginal productivity of e¤ort is relatively independent of the type of the job, and is mitigated either if job type and e¤ort are complements, or if they are substitutes.