Negative / Null Result ReportOpen accessComputer Science
Hassan Bassereh, Vahid Salari, Farhad Shahbazi et al. · 2015 · arXiv
We consider quantum excitation energy transport (EET) in a network of two-state nodes in the Markovian approximation by employing the Lindblad formulation. We find that EET from an initial site, where the excitation is inserted to the sink, is generally inefficient due to the inhibition of transport by localization of the excitation wave packet in a symmetric, fully-connected network. We demonstrate that the EET efficiency can be significantly increased up to %100 by perturbing hopping transport between the initial node and the one connected directly to the sink, while the rate of energy trans
Negative / Null Result ReportOpen accessComputer Science
Hugo Meric, Jose Miguel Piquer · 2013 · arXiv
We study the design of a DVB-S2 system in order to maximise spectrum efficiency. This task is usually challenging due to channel variability. Modern satellite communications systems such as DVB-SH and DVB-S2 rely mainly on a time sharing strategy to optimise the spectrum efficiency. Recently, we showed that combining time sharing with hierarchical modulation can provide significant gains (in terms of spectrum efficiency) compared to the best time sharing strategy. However, our previous design does not improve the DVB-S2 performance when all the receivers experience low or large signal-to-noise
Negative / Null Result ReportOpen accessComputer Science
Samuel F. Dodge, Lina J. Karam · 2013 · arXiv
The human visual system employs a selective attention mechanism to understand the visual world in an eficient manner. In this paper, we show how computational models of this mechanism can be exploited for the computer vision application of scene recognition. First, we consider saliency weighting and saliency pruning, and provide a comparison of the performance of different attention models in these approaches in terms of classification accuracy. Pruning can achieve a high degree of computational savings without significantly sacrificing classification accuracy. In saliency weighting, however,
Negative / Null Result ReportOpen accessComputer Science
Taisuke Kobayashi · 2020 · arXiv
This paper proposes a new optimizer for deep learning, named d-AmsGrad. In the real-world data, noise and outliers cannot be excluded from dataset to be used for learning robot skills. This problem is especially striking for robots that learn by collecting data in real time, which cannot be sorted manually. Several noise-robust optimizers have therefore been developed to resolve this problem, and one of them, named AmsGrad, which is a variant of Adam optimizer, has a proof of its convergence. However, in practice, it does not improve learning performance in robotics scenarios. This reason is h
Negative / Null Result ReportOpen accessComputer Science
Domenic Rosati · 2023 · arXiv
Communication of scientific findings to the public is important for keeping non-experts informed of developments such as life-saving medical treatments. However, generating readable lay summaries from scientific documents is challenging, and currently, these summaries suffer from critical factual errors. One popular intervention for improving factuality is using additional external knowledge to provide factual grounding. However, it is unclear how these grounding sources should be retrieved, selected, or integrated, and how supplementary grounding documents might affect the readability or rele
Negative / Null Result ReportOpen accessComputer Science
Ushak Rahaman, Soebur Razzaque · 2021 · arXiv
The $ν_μ\to ν_e$ oscillation probability over short baseline ($\lesssim 1$~km) would be negligible in case the mixing matrix for three active neutrinos is unitary. However, in case of non-unitary mixing of three neutrinos, this probability would be non-negligible due to the so-called "zero distance" effect. Hence, the near detector of the accelerator experiments such as NO$ν$A can provide strong constraints on the parameters of the non-unitary mixing with very large statistics. By analyzing the NO$ν$A near detector data we find that the non-unitary mixing does not improve fits to the $ν_e$ or
Negative / Null Result ReportOpen accessComputer Science
Ewout van den Berg, Michael P. Friedlander · 2009 · arXiv
The joint-sparse recovery problem aims to recover, from sets of compressed measurements, unknown sparse matrices with nonzero entries restricted to a subset of rows. This is an extension of the single-measurement-vector (SMV) problem widely studied in compressed sensing. We analyze the recovery properties for two types of recovery algorithms. First, we show that recovery using sum-of-norm minimization cannot exceed the uniform recovery rate of sequential SMV using $\ell_1$ minimization, and that there are problems that can be solved with one approach but not with the other. Second, we analyze
Negative / Null Result ReportMedicine
Orhan B, Nauta M · 2026 · Death studies
Meaning Management Theory suggests that engaging with meaning-related resources helps individuals constructively regulate consciously experienced death anxiety. Consistent with that theory, we tested whether a single-session, online…
View details →DOI: 10.1080/07481187.2026.2659888 Negative / Null Result ReportOpen accessAgricultural and Biological Sciences
Louis Jalouzot, Alexis Thual, Yair Lakretz et al. · 2025 · arXiv
We investigate optimal strategies for decoding perceived natural speech from fMRI data acquired from a limited number of participants. Leveraging Lebel et al. (2023)'s dataset of 8 participants, we first demonstrate the effectiveness of training deep neural networks to predict LLM-derived text representations from fMRI activity. Then, in this data regime, we observe that multi-subject training does not improve decoding accuracy compared to single-subject approach. Furthermore, training on similar or different stimuli across subjects has a negligible effect on decoding accuracy. Finally, we fin
Negative / Null Result ReportOpen accessComputer Science
Yulin Chen, He He, Chen Zhao · 2026 · arXiv
Reinforcement Learning with Verifiable Reward (RLVR) has proven effective in improving Large Language Model's (LLM) reasoning ability. However, the learning dynamics of RLVR remain underexplored. In this paper, we reveal a counterintuitive phenomenon: among hard examples that the model initially struggles with, a substantial subset remains unlearnable even when correct rollouts are present. To understand the phenomenon, we first demonstrate that existing optimization and sampling techniques fail to resolve unlearnability. With cross-example gradient analysis, we show that unlearnable examples
Negative / Null Result ReportOpen accessComputer Science
Hyeong Kyu Choi, Xiaojin Zhu, Sharon Li · 2025 · arXiv
Multi-Agent Debate~(MAD) has emerged as a promising paradigm for improving the performance of large language models through collaborative reasoning. Despite recent advances, the key factors driving MAD's effectiveness remain unclear. In this work, we disentangle MAD into two key components--Majority Voting and inter-agent Debate--and assess their respective contributions. Through extensive experiments across seven NLP benchmarks, we find that Majority Voting alone accounts for most of the performance gains typically attributed to MAD. To explain this, we propose a theoretical framework that mo
Negative / Null Result ReportOpen accessComputer Science
Mitchell A. Gordon, Kevin Duh, Nicholas Andrews · 2020 · arXiv
Pre-trained universal feature extractors, such as BERT for natural language processing and VGG for computer vision, have become effective methods for improving deep learning models without requiring more labeled data. While effective, feature extractors like BERT may be prohibitively large for some deployment scenarios. We explore weight pruning for BERT and ask: how does compression during pre-training affect transfer learning? We find that pruning affects transfer learning in three broad regimes. Low levels of pruning (30-40%) do not affect pre-training loss or transfer to downstream tasks a
Negative / Null Result ReportOpen accessComputer Science
Tovly Deutsch, Masoud Jasbi, Stuart Shieber · 2020 · arXiv
Readability assessment aims to automatically classify text by the level appropriate for learning readers. Traditional approaches to this task utilize a variety of linguistically motivated features paired with simple machine learning models. More recent methods have improved performance by discarding these features and utilizing deep learning models. However, it is unknown whether augmenting deep learning models with linguistically motivated features would improve performance further. This paper combines these two approaches with the goal of improving overall model performance and addressing th
Negative / Null Result ReportOpen accessComputer Science
C. Fernandez-Ramirez, A. M. Bernstein · 2012 · arXiv
With the availability of the new neutral pion photoproduction from the proton data from the A2 and CB-TAPS Collaborations at Mainz it is mandatory to revisit Heavy Baryon Chiral Perturbation Theory (HBChPT) and address the extraction of the partial waves as well as other issues such as the value of the low-energy constants, the energy range where the calculation provides a good agreement with the data and the impact of unitarity. We find that, within the current experimental status, HBChPT with the fitted LECs gives a good agreement with the existing neutral pion photoproduction data up to $\s
Negative / Null Result ReportOpen accessComputer Science
Osvaldo Simeone, Haim H. Permuter · 2011 · arXiv
For memoryless sources, delayed side information at the decoder does not improve the rate-distortion function. However, this is not the case for more general sources with memory, as demonstrated by a number of works focusing on the special case of (delayed) feedforward. In this paper, a setting is studied in which the encoder is potentially uncertain about the delay with which measurements of the side information are acquired at the decoder. Assuming a hidden Markov model for the sources, at first, a single-letter characterization is given for the set-up where the side information delay is arb
Negative / Null Result ReportOpen accessPhysics
Patrick Murphy, Misha Perepelitsa, Ilya Timofeyev et al. · 2023 · arXiv
Studies in the collective motility of organisms use a range of analytical approaches to formulate continuous kinetic models of collective dynamics from rules or equations describing agent interactions. However, the derivation of these kinetic models often relies on Boltzmann's hypothesis of "molecular chaos", that correlations between individuals are short-lived. While this assumption is often the simplest way to derive tractable models, it is often not valid in practice due to the high levels of cooperation and self-organization present in biological systems. In this work, we illustrated this
Negative / Null Result ReportOpen accessPhysics
Li-Xin Li, Jeremiah P. Ostriker · 2000 · arXiv
We use the semi-analytical approach to analyze gravitational lensing of quasars by dark halos in various cold dark matter (CDM) cosmologies, in order to determine the sensitivity of the prediction probabilities of images separations to the input assumptions regarding halos and cosmologies. The mass function of dark halos is assumed to be given by the Press-Schechter function. The mass density profile of dark halos is alternatively taken to be the singular isothermal sphere (SIS), the Navarro-Frenk-White (NFW) profile, or the generalized NFW profile. The cosmologies include: the Einstein-de Sit
Negative / Null Result Report
Bernard B. Dzoma, Nigel Wilhelm, Matthew Denton et al. · 2026 · Plant and Soil
Abstract Background and aims Residual imidazolinone herbicides are widely recognised for constraining the growth of rotational legume crops; however, little is known about how individual active ingredients including imazapyr and imazamox…
View details →DOI: 10.1007/s11104-026-08682-6 Negative / Null Result ReportOpen accessPhysics
Sayan Dutta, Maria C. Lesniewski, Muhammad Nawaz Qaisrani et al. · 2025 · arXiv
Conjugated organic molecules play a central role in a wide range of optoelectronic devices, including organic light-emitting diodes, organic field-effect transistors, and organic solar cells. A major bottleneck in the computational design of these materials is the discrepancy between simulation and experimental time and length scales. Coarse-graining (CG) offers a promising solution to bridge this gap by reducing redundant degrees of freedom and smoothing the potential energy landscape, thereby significantly accelerating molecular dynamics simulations. However, standard CG models are typically
Negative / Null Result Report
Peace N Eneh, Jennifer Bath · 2011 · The FASEB Journal
Soil transmitted helminths have attracted interest in clinical research due their ability to parasitize human hosts. These parasitic species such as H. polygyrus infest host cell and suppress the immune system by secreting a fatty acid and…
View details →DOI: 10.1096/fasebj.25.1_supplement.918.1 Negative / Null Result Report
Cammi Borden, Kaila A. Vento · 2026 · Aerospace Medicine and Human Performance
INTRODUCTION: Aircrew reluctance to urinate during flights, coupled with the risk of urinary tract infections (UTIs), represents an under-explored occupational health issue. The effects of UTIs on aviation-relevant tasks are not well…
View details →DOI: 10.3357/amhp.6787.2026 Negative / Null Result Report
Shaukat Ali Syed, Mazhar Iqbal Bhatti · 2022 · Pakistan BioMedical Journal
Purpose of the current study is to investigate the effect of attachment with significant others one motion regulation and quality of sleep among youth was to find out the impact of attachment with parents and peers on emotional regulation…
View details →DOI: 10.54393/pbmj.v5i1.155 Negative / Null Result Report
L Rose · 2011 · Focus on Alternative and Complementary Therapies
Andersen D, Løssl K, Andersen AN, Fürbringer J, Bach H, Simonsen J, Larsen EC. Acupuncture on the day of embryo transfer: a randomized controlled trial of 635 patients. Reprod Biomed Online 2010; 21: 366–372.
View details →DOI: 10.1111/j.2042-7166.2011.01091_6.x Negative / Null Result Report
A.A.M. Redhwan, A. Arifuddin, A.M. Syafiq et al. · 2024 · Journal of Advanced Research Design
Selection of significant machining parameters before the cutting process is necessary to produce the best outcome in the machining performances. The use of cutting fluids due to their cooling capabilities helps in producing a good finished…
View details →DOI: 10.37934/ard.113.1.110 Negative / Null Result Report
Zygy Roe-Zurz, Liliana Madrigal, Rahul Sharma et al. · 2025 · Journal of the Endocrine Society
Abstract Disclosure: Z. Roe-Zurz: None. L. Madrigal: None. Graves’ ophthalmopathy (GO) is a serious complication of autoimmune hyperthyroidism, affecting approximately 30% of patients. It is characterized by immune-mediated inflammation of…
View details →DOI: 10.1210/jendso/bvaf149.2207 Negative / Null Result Report
Eriko Katsuta, Kazuaki Takabe, Alex Adjei et al. · 2020 · Cancer Research
Abstract Background: PIM2 is overexpressed in hematopoietic and solid cancers, and is involved in multiple signaling pathways. In hematologic malignancies, PIM2 has been shown to be a pro-survival factor and demonstrated to be a possible…
View details →DOI: 10.1158/1538-7445.am2020-6426 Negative / Null Result Report
Aliasuddin Aliasuddin, Nanda Rahmi, Fathina Almahira Sakhi · 2026 · International Journal of Energy Economics and Policy
This study investigates the dynamic influence of carbon dioxide (CO₂) emissions, labor, and capital formation on agricultural productivity in Indonesia, utilizing annual data from 2000 to 2023 and employing an Autoregressive Distributed…
View details →DOI: 10.32479/ijeep.22400 Negative / Null Result Report
Kartik Sahu · 2026 · International Journal For Multidisciplinary Research
Abstract Recently the increasing of urbanization larger number of flats, buildings apartment and hotels are establish rapidly. For that the heat is increase due to the roof of the buildings and tremendous use air condition, hot air relies…
View details →DOI: 10.36948/ijfmr.2026.v08i02.70904 Negative / Null Result ReportMedicine
Mitsuhara, Shimizu, Ebihara et al. · 2026 · Acute medicine & surgery
This study aimed to evaluate whether early enteral nutrition can be administered without increasing gastrointestinal complications in patients receiving mechanical circulatory support. This retrospective observational study was conducted…
View details →DOI: 10.1002/ams2.70132 Negative / Null Result Report
· 2023 · Human Resource Management International Digest
Purpose This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies. Design/methodology/approach This briefing is prepared by an independent…
View details →DOI: 10.1108/hrmid-09-2022-0247 