Improving the fairness of FAST TCP to new flows

It has been observed that FAST TCP, and the related protocol TCP Vegas, suffer unfairness when many flows arrive at a single bottleneck link, without intervening departures. We show that the effect is even more marked if a new flow arrives when existing flows share bandwidth fairly, and propose a simple method to ameliorate this effect

A tighter constraint on Earth-system sensitivity from long-term temperature and carbon-cycle observations

Developing sound strategies to manage climate risks hinges critically on Earth-system properties, including the Earth-system sensitivity (ESS). Current ESS estimates are subject to large and deep uncertainties. Long-term carbon cycle models can provide a useful avenue to constrain ESS, but previous efforts either lack a formal data assimilation framework, or focus on discrete paleoevents. Here, we improve on ESS estimates by using a Bayesian approach to fuse deep-time paleoclimate CO2 and temperature data over the last 420 Myrs with a long-term carbon cycle model. Our best sensitivity estimate of 3.4 deg C (2.6-4.7 deg C; 5-95% range) shows a narrower range than previous assessments, implying increased learning. Our sensitivity analyses indicate that during the Cretaceous, a much weaker chemical weathering efficiency of gymnosperms and shift in the timing of gymnosperm- to angiosperm-dominated vegetation yield better agreement with temperature records. Research into improving the understanding about these plant-assisted weathering mechanisms hence provides potentially powerful avenues to further constrain this fundamental Earth-system property

©2008 INFORMS A Price Discrimination Model of Trade Promotions

doi 10.1287/mksc.1070.031

A Molecular-Splicing Strategy for Constructing a Near-Infrared Fluorescent Probe for UDP-Glucuronosyltransferase 1A1

UDP-glucuronosyltransferase 1A1 (UGT1A1) is a vital metabolic enzyme responsible for the clearance of endogenous substances and drugs. Hitherto, the development of fluorescent probes for UGTs was severely restricted due to the poor isoform selectivity and on–off or blue-shifted fluorescence response. Herein, we established a novel “molecular-splicing” strategy to construct a highly selective near-infrared (NIR) fluorescent probe, HHC, for UGT1A1, which exhibited a NIR signal at 720 nm after UGT1A1 metabolism. HHC was then successfully used for the real-time imaging of endogenous UGT1A1 in living cells and animals and to monitor the bile excretion function. In summary, an isoform-specific NIR fluorescent probe has been developed for monitoring UGT1A1 activity in living systems, high-throughput screening of novel UGT1A1 inhibitors and visual evaluation of bile excretion function.</p

Probabilistic Constellation Shaping for OFDM-Based ISAC Signaling

Integrated Sensing and Communications (ISAC) has garnered significant attention as a promising technology for the upcoming sixth-generation wireless communication systems (6G). In pursuit of this goal, a common strategy is that a unified waveform, such as Orthogonal Frequency Division Multiplexing (OFDM), should serve dual-functional roles by enabling simultaneous sensing and communications (S&C) operations. However, the sensing performance of an OFDM communication signal is substantially affected by the randomness of the data symbols mapped from bit streams. Therefore, achieving a balance between preserving communication capability (i.e., the randomness) while improving sensing performance remains a challenging task. To cope with this issue, in this paper we analyze the ambiguity function of the OFDM communication signal modulated by random data. Subsequently, a probabilistic constellation shaping (PCS) method is proposed to devise the probability distributions of constellation points, which is able to strike a scalable S&C tradeoff of the random transmitted signal. Finally, the superiority of the proposed PCS method over conventional uniformly distributed constellations is validated through numerical simulations

Visual High-Throughput Screening for Developing a Fatty Acid Amide Hydrolase Natural Inhibitor Based on an Enzyme-Activated Fluorescent Probe

Fatty acid amide hydrolase (FAAH) is an important drug target for the treatment of many disease related conditions such as pain, inflammation, and mood disorders due to its vital role in the metabolism of endocannabinoid. In our present work, a FAAH-activated fluorescent probe named THPO was developed, which possessed high selectivity and excellent sensitivity for FAAH in complex systems. Critically, its metabolite 7-amino-3H-phenoxazin-3-one (AHPO) has long excitation and emission wavelengths and high fluorescence quantum yield, which are necessary for monitoring the activity of FAAH in living systems. In addition, a visual high-throughput screening method for FAAH inhibitors was established using THPO, which resulted in the discovery of an efficient natural inhibitor Neobavaisoflavone that was identified from 68 traditional herbal medicines. These results indicated that THPO can be used as a molecular tool for the rapid evaluation of FAAH activity in complex systems as well as providing an effective approach to screen FAAH inhibitors and providing a boost for the discovery of therapeutic agents toward FAAH related diseases. </p