Negative / Null Result ReportOpen accessComputer Science
Samir D. Mathur · 2019 · arXiv
The vacuum must contain virtual fluctuations of black hole microstates for each mass $M$. We observe that the expected suppression for $M\gg m_p$ is counteracted by the large number $Exp[S_{bek}]$ of such states. From string theory we learn that these microstates are extended objects that are resistant to compression. We argue that recognizing this `virtual extended compression-resistant' component of the gravitational vacuum is crucial for understanding gravitational physics. Remarkably, such virtual excitations have no significant effect for observable systems like stars, but they resolve tw
Negative / Null Result ReportOpen accessPhysics
L. S. R. Cavalcante, D. R. da Costa, G. A. Farias et al. · 2021 · arXiv
The effect of an external in-plane electric field on neutral and charged exciton states in two-dimensional (2D) materials is theoretically investigated. These states are argued to be strongly bound, so that electron-hole dissociation is not observed up to high electric field intensities. Trions in the anisotropic case of monolayer phosphorene are demonstrated to especially robust under electric fields, so that fields as high as 100 kV/cm yield no significant effect on the trion binding energy or probability density distribution. Polarizabilities of excitons are obtained from the parabolicity o
Negative / Null Result Report
Katsuhiko Naruse, Itsuko Okada, Masahiko Ogawa et al. · 2020 · International Journal of Gynecology & Obstetrics
Intra‐anal swabbing for GBS in pregnant women did not improve the detection rate compared to perianal swabbing, but increased the detection of ESBL‐producing E.coli .
View details →DOI: 10.1002/ijgo.13238 Negative / Null Result Report
Mark W. Clark · 2021 · Science of Law
The purpose of this study is to analyze men who have preyed on prostitutes and determine if similarities exist between the offenders who used the Internet to find sexual partners with sexual killers who did not utilize the Internet. We…
View details →DOI: 10.55284/76 Negative / Null Result ReportOpen accessComputer Science
Imam tahyudin · 2013 · arXiv
The purpose of this research was to determine the influence of Internet Retail Service Quality (IRSQ) (website performance, access, security, sensation, and information) to the satisfaction www.kebanaran.com online shoppers. The method of analysis used was path analysis. Based on the research results influence IRSQ variables (performance, access, sensation, and information security), performance variables (X1), access (X2) and sensation (X3) had no significant effect on satisfaction (Y). It showsthat the online shopping website www.kebanaran.com already apply standard terms online stores in ge
Negative / Null Result ReportOpen accessPhysics
L. R. Abramo, R. P. Woodard · 1998 · arXiv
We consider quantum mechanical corrections to a homogeneous, isotropic and spatially flat geometry whose scale factor expands classically as a general power of the co-moving time. The effects of both gravitons and the scalar inflaton are computed at one loop using the manifestly causal formalism of Schwinger with the Feynman rules recently developed by Iliopoulos {\it et al.} We find no significant effect, in marked contrast with the result obtained by Mukhanov {\it et al.} for chaotic inflation based on a quadratic potential. By applying the canonical technique of Mukhanov {\it et al.} to the
Negative / Null Result ReportOpen accessPhysics
Ulrich Kolb, Isabelle Baraffe · 1999 · arXiv
Using improved, up-to-date stellar input physics tested against observations of low-mass stars and brown dwarfs we calculate the secular evolution of low-mass donor cataclysmic variables (CVs), including those which form with a brown dwarf donor. Our models confirm the mismatch between the calculated minimum period (Pmin ~ 70 min) and the observed short-period cut-off (~ 80 min) in the CV period histogram. We find that tidal and rotational corrections applied to the one-dimensional stellar structure equations have no significant effect on the period minimum. Theoretical period distributions sy
Negative / Null Result ReportOpen accessPhysics
X. S. Wu, P. W. Adams, Y. Yang et al. · 2005 · arXiv
We present a detailed study of the effects of interface spin-orbit coupling (ISOC) on the critical field behavior of non-centrosymmetric (NCS), ultra-thin superconducting Be/Au bilayers. Parallel field measurements were made in bilayers with Be thicknesses in the range of 2 - 10 nm and Au coverages of 0.5 nm. Though the Au had no significant effect on the superconducting gap, it produced profound changes in the spin states of the system. In particular, the parallel critical field exceeded the Clogston limit by an order of magnitude in the thinnest films studied. In addition, the parallel criti
Negative / Null Result ReportOpen accessComputer Science
Bruce W. Lee, JaeHyuk Lim · 2024 · arXiv
We argue that language-only models don't learn the physical manifestation of language. We present an empirical investigation of visual-auditory properties of language through a series of tasks, termed H-Test. These tasks highlight a fundamental gap between human linguistic understanding and the sensory-deprived linguistic understanding of LLMs. In support of our hypothesis, 1. deliberate reasoning (Chain-of-Thought), 2. few-shot examples, or 3. stronger LLM from the same model family (LLaMA 2 13B -> LLaMA 2 70B) has no significant effect on H-Test performance. We bring in the philosophical cas
Negative / Null Result ReportOpen accessPhysics
Stephen C. Thompson, Richard J. Meyer, Douglas C. Markley · 2013 · arXiv
Underwater acoustic transducers often include a stack of thickness polarized piezoelectric material pieces of alternating polarity interspersed with electrodes, bonded together and electrically connected in parallel. The stack is normally much shorter than a quarter wavelength at the fundamental resonance frequency, so that the mechanical behavior of the transducer is not affected by the segmentation. When the transducer bandwidth is less than a half octave, as has conventionally been the case, stack segmentation has no significant effect on the mechanical behavior of the device. However, when
Negative / Null Result ReportOpen accessPhysics
Tanech Klangburam, Chakrit Pongkitivanichkul · 2025 · arXiv
We investigate the effects of the ALP-mediated dark matter (DM) model on neutron star properties using the Quantum Hadrodynamics model (QHD). Using the relativistic mean-field approximation with the QHD-ALP-DM framework, we compute the equation of state (EoS) of neutron stars. Based on our previous study, we find that typical ALP parameter values have no significant effect on the EoS. We then explore various parametrizations of this model by varying the DM Fermi momentum, $q_f$, and DM mass, $m_χ$. Our results show that increasing $q_f$ or $m_χ$ shifts the energy density to higher values while
Negative / Null Result ReportOpen accessEconomics, Econometrics and Finance
Misha Perepelitsa · 2022 · arXiv
In this paper we give an elementary analysis of economics of Bitcoin that combines the transaction demand by the consumers and the supply of hashrate by miners. We argue that the decreasing block reward will have no significant effect on the exchange rate (price) of Bitcoin and thus the network will be transitioning to a regime where transaction fees will play a bigger part of miners' revenue. We consider a simple model where consumers demand bitcoins for transactions, but not for hoarding bitcoins, and we analyze market equilibrium where the demand is matched with the hashrate supplied by min
Negative / Null Result ReportOpen accessEngineering
Rancy Chepchirchir, Jill Sunday, Raymond Confidence et al. · 2025 · arXiv
In Sub-Saharan Africa (SSA), the utilization of lower-quality Magnetic Resonance Imaging (MRI) technology raises questions about the applicability of machine learning methods for clinical tasks. This study aims to provide a robust deep learning-based brain tumor segmentation (BraTS) method tailored for the SSA population using a threefold approach. Firstly, the impact of domain shift from the SSA training data on model efficacy was examined, revealing no significant effect. Secondly, a comparative analysis of 3D and 2D full-resolution models using the nnU-Net framework indicates similar perfor
Negative / Null Result ReportOpen accessPhysics
Xiao-ke xu, Jie Zhang, Ping Li et al. · 2011 · arXiv
Traditionally, there is no evidence suggesting that there are strong ties between the rich-club property and the function of complex networks. In this study, we find that whether a very small portion of rich nodes connected to each other or not can strongly affect the frequency of occurrence of basic building blocks (motif) within networks, and therefore the function, of a heterogeneous network. Conversely whether a homogeneous network has a rich-club property or not generally has no significant effect on its structure and function. These findings open the possibility to optimize and control t
Negative / Null Result ReportOpen accessPhysics
Vikrant Yadav, Rajpal, Pardeep et al. · 2024 · arXiv
In this letter, we report the observational constraints on a Bianchi type I anisotropic extension of $w$CDM model with spatial curvature from observational data including Baryon Acoustic Oscillations (BAO), Cosmic chronometers (CC), Big Bang nucleosynthesis (BBN), Pantheon+ (PP) compilation of SNe Ia and SH0ES Cepheid host distance anchors. The anisotropy is found to be of the order $10^{-13}$, which interplay with spatial curvature to reduce $H_0$ tension by $\sim 1σ$ as found in the analyses with BAO+CC+BBN+PP combination of data, while no significant effect of anisotropy is observed with BA
Negative / Null Result ReportOpen accessPhysics
Andrey A. Kistanov, Yongqing Cai, Kun Zhou et al. · 2016 · arXiv
We investigate the electronic structure and chemical activity of rippled phosphorene induced by large compressive strains via first-principles calculation. It is found that phosphorene is extraordinarily bendable, enabling the accommodation of ripples with large curvatures. Such highly rippled phosphorene shows a strong anisotropy in electronic properties. For ripples along the armchair direction, the band gap changes from 0.84 to 0.51 eV for the compressive strain up to -20% and further compression shows no significant effect, for ripples along the zigzag direction, semiconductor to metal tra
Negative / Null Result ReportOpen accessEconomics, Econometrics and Finance
Markus Dertwinkel-Kalt, Max R. P. Grossmann · 2025 · arXiv
When environmental regulations are unpopular, policymakers often attribute resistance to information frictions and poor communication. We test this idea in the context of a major climate policy: Germany's Heating Law of 2023, which mandates the phase-out of fossil fuel heating. Through a survey experiment with property owners, we examine whether providing comprehensive information about the regulation's costs, requirements, and timeline affects adoption decisions and policy support. Despite successfully increasing factual knowledge, information provision has no significant effect on intended t
Negative / Null Result ReportOpen accessPhysics
Benjamin Poole, Bartosz Barzdajn, Daniele Dini et al. · 2019 · arXiv
The thermal effects of plastic and frictional heat generation and elevated temperature were examined along with the role of adhesion in the context of galling wear, using a representative crystal plasticity, normally loaded, sliding surface model. Galling frequency behaviour was predicted for 316L steel. Deformation of the surfaces was dominated by the surface geometry, with no significant effect due to variations in frictional models. Plastic and frictional heating were found to have a minimal effect on the deformation of the surface, with the rapid conduction of heat preventing any highly lo
Negative / Null Result ReportOpen accessComputer Science
Varun Kotte · 2026 · arXiv
Prompt-only, single-step LLM query rewriting, where a rewrite is generated from the query alone without retrieval feedback, is commonly used in production RAG pipelines, but its effect on dense retrieval is poorly understood. We present a systematic empirical study across three BEIR benchmarks, two dense retrievers, and multiple training configurations, and find strongly domain-dependent behavior: rewriting degrades nDCG@10 by 9.0 percent on FiQA, improves it by 5.1 percent on TREC-COVID, and has no significant effect on SciFact. We identify a consistent mechanism: degradations co-occur with r
Negative / Null Result ReportOpen accessAgricultural and Biological Sciences
Anna Seigal, Portia Mira, Bernd Sturmfels et al. · 2016 · arXiv
Nosocomial outbreaks of bacteria are well-documented. Based on these incidents, and the heavy usage of antibiotics in hospitals, it has been assumed that antibiotic resistance evolves in hospital environments. To test this assumption, we studied resistance phenotypes of bacteria collected from patient isolates at a community hospital over a 2.5-year period. A graphical model analysis shows no association between resistance and patient information other than time of arrival. This allows us to focus on time course data. We introduce a Hospital Transmission Model, based on negative binomial delay
Negative / Null Result ReportOpen accessPhysics
Peter Erwin, Linda S. Sparke · 2002 · arXiv
We present results from an imaging survey of an unbiased sample of thirty-eight early-type (S0--Sa), low-inclination, optically barred galaxies in the field. Our goal was to find and characterize central stellar and gaseous structures: secondary bars, inner disks, and nuclear rings. Bars inside bars are surprisingly common: at least one quarter of the sample galaxies (possibly as many as 40%) are double-barred, with no preference for Hubble type or the strength of the primary bar. A typical secondary bar is ~12% of the size of its primary bar and 240--750 pc in radius. We see no significant ef
Negative / Null Result ReportOpen accessPhysics
D. Apai, M. R. Meyer, P. Hinz et al. · 2007 · arXiv
We present results from two high-contrast imaging surveys that exploit a novel technique, L-band angular differential imaging. Our first survey targeted 21 young stars in the Beta Pic and Tuc-Hor moving groups with VLT/NACO reaching typical sensitivities of 20 AU. The statistical analysis of the null result demonstrates that the giant planet population is truncated at 30 AU or less (90% confidence level). Our second, on-going MMT/Clio survey utilizes the unique sensitivity achieved in the L-band for old planets to probe all M-dwarf stars within 6 pc. The proximity of these targe
Negative / Null Result ReportMedicine
Mohammed Abdul, Bernard, Yates · 2026 · Cureus
Background The optimal choice of polyethylene insert in total knee arthroplasty (TKA) continues to cause contention. Rotating platform bearings (RP) have theoretical advantages but have failed to demonstrate a functional difference…
View details →DOI: 10.7759/cureus.109613 Negative / Null Result ReportMedicine
Geysenbergh, Debrock, Lie Fong et al. · 2026 · Human reproduction (Oxford, England)
Does a natural cycle result in higher clinical pregnancy rates (CPR) with foetal heartbeat compared to an artificial cycle for frozen-thawed embryo transfer (FET) preparation in ovulatory women? The CPR with foetal heartbeat did not differ…
View details →DOI: 10.1093/humrep/deag095 Negative / Null Result ReportMedicine
El-Tanani, Wali, Rabbani et al. · 2026 · Pharmaceuticals (Basel, Switzerland)
In spite of plausible biology, the majority of oncology trials involving drug repurposing have failed to demonstrate any efficacy. Numerous factors can potentially cause failure, including issues with dosing, drug strength, the trial…
View details →DOI: 10.3390/ph19060957 Negative / Null Result ReportOpen accessMicrobiology
Ruliaty Lisa, Amalia Indrian Rizka, Nur Abidin et al. · 2023 · BIO Web of Conferences
This study was aimed to know the effect of hatching and survival rate of milkfish larvae (Chanos chanos) treated with nanosilver. Three concentrations of nanosilver such as 0.25 ppm, 0.5 ppm and 0.75 ppm were applied to culture media at least an hour before stocking. Newly hatched larvae were stocked at the density of 50 pcs l-1, and it was reared for 25 days in 5 m3 of concrete tank. Result of the study found that no significant effect (p>0.05) of the treatments given on hatching rate and survival of milkfish larvae. However, larvae treated with nanosilver tend to gain higher hatching rate (6
View details →DOI: 10.1051/bioconf/20237401015 Negative / Null Result ReportOpen accessNaval architecture. Shipbuilding. Marine engineering
Chenfang Wang, Longxi Han, Yi Zhang et al. · 2023 · Journal of Marine Science and Engineering
The natural dispersion of oil depends on the oil types, wave-mixing energy, and the temperature and salinity of water. Laboratory experiments were conducted to investigate the effects of these factors on oil dispersion. The results demonstrated that the increase in temperature significantly enhanced the oil dispersion efficiency, particularly for low-viscosity oils. At 30 °C, the dispersion efficiency is 2 times higher than that at 15 °C, while salinity has no significant effect on dispersion efficiency. Nonlinear fitting results revealed an exponential increase in dispersion efficiency with t
View details →DOI: 10.3390/jmse12010047 Negative / Null Result ReportOpen accessMedicine
Diptasree Maitra Ghosh, Dinesh Kumar, Sridhar Poosapadi Arjunan et al. · 2017 · PLoS ONE
This study has described and experimentally validated the differential electrodes surface electromyography (sEMG) model for tibialis anterior muscles during isometric contraction. This model has investigated the effect of pennation angle on the simulated sEMG signal. The results show that there is no significant effect of pennation angle in the range 0° to 20° to the single fibre action potential shape recorded on the skin surface. However, the changes with respect to pennation angle are observed in sEMG amplitude, frequency and fractal dimension. It is also observed that at different levels o
View details →DOI: 10.1371/journal.pone.0189036 Negative / Null Result ReportOpen accessAgriculture
Yasen H. Al tahan · 2005 · Mesopotamia Journal of Agriculture
In this study a specific gravity separator has been used in order to consider the effect of three levels of: longitudinal slop angles, vibration speeds, outlets for the produce and their effect on specific weight, productivity and seed purity. The results show the longitudinal horizontal slop angle (0) surpassed significantly in recording the greatest values for all characteristics of the study. While the second vibration speed surpassed significantly in specific weight and productivity and there were no significant effect in seed purity. in the product out lets, the first out lets achieved th
View details →DOI: 10.33899/magrj.2005.36122 Negative / Null Result ReportOpen accessMining engineering. Metallurgy
Yuming ZHANG, Xuefeng MEI · 2025 · Medžiagotyra
This work investigated the adhesion performance of recycled concrete with nano-SiO2 and nano-Al2O3 and steel bars in cold environments through freeze‒thaw cycle tests and tensile tests. The results show that the nanomaterials and number of freeze-thaw cycles have no significant effect on the damage morphology of the sample, but the adhesion strength and steel bar slip of the sample are considerably affected by the nanomaterials and number of freeze-thaw cycles. After the addition of the nanomaterials, the adhesion strength increased by 10.4 % (11.2 %), and the steel slip increased, by 17.3 % (
View details →DOI: 10.5755/j02.ms.38941 