Negative / Null Result ReportOpen accessComputer Science
Linas Vepstas · 2013 · arXiv
This report describes the suicidality prediction models created under the DARPA DCAPS program in association with the Durkheim Project [http://durkheimproject.org/]. The models were built primarily from unstructured text (free-format clinician notes) for several hundred patient records obtained from the Veterans Health Administration (VHA). The models were constructed using a genetic programming algorithm applied to bag-of-words and bag-of-phrases datasets. The influence of additional structured data was explored but was found to be minor. Given the small dataset size, classification between c
Negative / Null Result ReportOpen accessComputer Science
Mario Sanz-Guerrero, Katharina von der Wense · 2025 · arXiv
In-context learning (ICL) has transformed the use of large language models (LLMs) for NLP tasks, enabling few-shot learning by conditioning on labeled examples without finetuning. Despite its effectiveness, ICL is prone to errors, especially for challenging examples. With the goal of improving the performance of ICL, we propose corrective in-context learning (CICL), an approach that incorporates a model's incorrect predictions alongside ground truth corrections into the prompt, aiming to enhance classification accuracy through self-correction. However, contrary to our hypothesis, extensive exp
Negative / Null Result ReportOpen accessComputer Science
Hui Zhang, Kiduk Yang, Elin Jacob · 2015 · arXiv
Despite limited success, information retrieval (IR) systems today are not intelligent or reliable. IR systems return poor search results when users formulate their information needs into incomplete or ambiguous queries (i.e., weak queries). Therefore, one of the main challenges in modern IR research is to provide consistent results across all queries by improving the performance on weak queries. However, existing IR approaches such as query expansion are not overly effective because they make little effort to analyze and exploit the meanings of the queries. Furthermore, word sense disambiguati
Negative / Null Result ReportOpen accessComputer Science
Roberto Casadio, Fabio Finelli, Mattia Luzzi et al. · 2004 · arXiv
Improved Wentzel-Kramers-Brillouin (WKB)-type approximations are presented in order to study cosmological perturbations beyond the lowest order. Our methods are based on functions which approximate the true perturbation modes over the complete range of the independent (Langer) variable, from sub-horizon to super-horizon scales, and include the region near the turning point. We employ both a perturbative Green's function technique and an adiabatic (or ``semiclassical'') expansion (for a linear turning point) in order to compute higher order corrections. Improved general expressions for the WKB
Negative / Null Result ReportOpen accessComputer Science
Gokhan Alkac, Luca Basanisi, Ercan Kilicarslan et al. · 2017 · arXiv
We revisit the problem of the bulk-boundary unitarity clash in 2 + 1 dimensional gravity theories, which has been an obstacle in providing a viable dual two-dimensional conformal field theory for bulk gravity in anti-de Sitter (AdS) spacetime. Chiral gravity, which is a particular limit of cosmological topologically massive gravity (TMG), suffers from pertur- bative log-modes with negative energies inducing a non-unitary logarithmic boundary field theory. We show here that any f(R) extension of TMG does not improve the situation. We also study the perturbative modes in the metric formulation o
Negative / Null Result ReportOpen accessEngineering
Deepak Singla, Soham Chatterjee, Lavanya Ramapantulu et al. · 2020 · arXiv
Applications in the Internet of Video Things (IoVT) domain have very tight constraints with respect to power and area. While neuromorphic vision sensors (NVS) may offer advantages over traditional imagers in this domain, the existing NVS systems either do not meet the power constraints or have not demonstrated end-to-end system performance. To address this, we improve on a recently proposed hybrid event-frame approach by using morphological image processing algorithms for region proposal and address the low-power requirement for object detection and classification by exploring various convolut
Negative / Null Result ReportOpen accessComputer Science
Jin Zeng, Yang Liu, Gene Cheung et al. · 2022 · arXiv
A graph convolutional network (GCN) employs a graph filtering kernel tailored for data with irregular structures. However, simply stacking more GCN layers does not improve performance; instead, the output converges to an uninformative low-dimensional subspace, where the convergence rate is characterized by the graph spectrum -- this is the known over-smoothing problem in GCN. In this paper, we propose a sparse graph learning algorithm incorporating a new spectrum prior to compute a graph topology that circumvents over-smoothing while preserving pairwise correlations inherent in data. Specifica
Negative / Null Result ReportOpen accessComputer Science
Charles Jin, Melinda Sun, Martin Rinard · 2021 · arXiv
We propose a novel clustering mechanism based on an incompatibility property between subsets of data that emerges during model training. This mechanism partitions the dataset into subsets that generalize only to themselves, i.e., training on one subset does not improve performance on the other subsets. Leveraging the interaction between the dataset and the training process, our clustering mechanism partitions datasets into clusters that are defined by--and therefore meaningful to--the objective of the training process. We apply our clustering mechanism to defend against data poisoning attacks,
Negative / Null Result ReportOpen accessComputer Science
Zachary Baker, Yuxiao Li · 2025 · arXiv
Sparse Autoencoders (SAEs) have emerged as a promising approach for interpreting neural network representations by learning sparse, human-interpretable features from dense activations. We investigate whether incorporating variational methods into SAE architectures can improve feature organization and interpretability. We introduce the Variational Sparse Autoencoder (vSAE), which replaces deterministic ReLU gating with stochastic sampling from learned Gaussian posteriors and incorporates KL divergence regularization toward a standard normal prior. Our hypothesis is that this probabilistic sampl
Replication FailureOpen accessComputer Science
Xiqi Hao, Zengqing Wu, Yu-Xuan Qiu et al. · 2026 · arXiv
Multi-agent debate (MAD) is a promising strategy for improving LLM reasoning, but when agents converge on a shared answer, it is unclear whether that convergence reflects genuine deliberation or social compliance. We show that the conventional answer flip rate conflates three distinct mechanisms: spontaneous instability, stance-induced conformity, and reasoning-induced persuasion. Our three-source decomposition framework isolates each through controlled counterfactual conditions. In the primary MMLU-Pro setting, 37% of agent-question observations change under self-reflection alone, while robus
Negative / Null Result ReportOpen accessComputer Science
Paul Röttger, Janet B. Pierrehumbert · 2021 · arXiv
Language use differs between domains and even within a domain, language use changes over time. For pre-trained language models like BERT, domain adaptation through continued pre-training has been shown to improve performance on in-domain downstream tasks. In this article, we investigate whether temporal adaptation can bring additional benefits. For this purpose, we introduce a corpus of social media comments sampled over three years. It contains unlabelled data for adaptation and evaluation on an upstream masked language modelling task as well as labelled data for fine-tuning and evaluation on
Negative / Null Result ReportOpen accessArctic medicine. Tropical medicine
Yuelin Xiong, Huatang Luo, Hao Wang et al. · 2026 · PLoS Neglected Tropical Diseases
Background Schistosomiasis, a neglected tropical disease (NTD), remains a public health concern in China. Health education is a fundamental intervention for its control. Even in transmission-interrupted areas like Wuhan, sustained awareness is crucial. However, recent literature on school-based interventions evaluating knowledge, attitudes and practices (KAP) among children in such areas is limited. Objective This study aimed to evaluate and compare the effectiveness of peer-led education versus routine health education in improving schistosomiasis-related KAP among elementary students in an u
View details →DOI: 10.1371/journal.pntd.0013857 Negative / Null Result ReportOpen accessManagement. Industrial management
Majid Aligholizadeh, Mohammad Akbari, Fatemeh Zandian et al. · 2014 · مطالعات مدیریت راهبردی
The aim of Paper is to analyze and evaluate the performance of management in Tehran academic public libraries based on the model of EFQM that tries to identify the weak points and strong points of the management, plan for the improvement of strong points and resolve the weak points to get to a more competent and desirable situation in the society so that they can be able to improve their services and satisfy the needs of their members and customers more than ever. The methodology used to conduct this research is a survey and to collect the data a 72 item questionnaire of European Foundation fo
Failed Experiment ReportOpen accessTherapeutics. Pharmacology
Girish Parthan, Shobhit Bhansali, Anura V. Kurpad et al. · 2018 · BMC Pharmacology and Toxicology
Abstract Background Dipeptidyl peptidase 4 (DPP4) inhibitors improve glycemic control by promoting GLP1-mediated glucose-dependent insulin secretion and suppression of glucagon. Sitagliptin and vildagliptin have been shown to improve insulin sensitivity in patients with type 2 diabetes mellitus (T2DM). However, these patients had uncontrolled blood glucose at inclusion; therefore, the improvement in insulin sensitivity observed in these studies could be attributed to the drug per se and/or reduction in glucotoxicity. This study examines the effect of linagliptin on insulin sensitivity and β-ce
View details →DOI: 10.1186/s40360-018-0228-z Negative / Null Result ReportOpen accessDentistry
AHMAD ZAAZA, Nevien Mohamed, Gaffar El Halawani · 2025 · Alexandria Dental Journal
Introduction: Osseo-integrated dental implants were traditionally load-free for up to six months while they healed. Patients usually feel dissatisfied with the long loading times. Several studies have been conducted to improve osseointegration, decrease loading time, and increase patient satisfaction.Objectives: This study aimed to evaluate and compare both clinically and radiographically the effect of hyaluronic acid (HA) versus Titanium-Platelet Rich Fibrin (T-PRF) in enhancing osseointegration around anterior maxillary dental implants. Materials and Methods: Twelve patients with extracted m
View details →DOI: 10.21608/adjalexu.2024.282413.1497 Negative / Null Result ReportOpen accessMedicine
Leela McKinnon, David R Samson, Charles L Nunn et al. · 2022 · PLoS ONE
Sleep duration, quality, and rest-activity pattern-a measure for inferring circadian rhythm-are influenced by multiple factors including access to electricity. Recent findings suggest that the safety and comfort afforded by technology may improve sleep but negatively impact rest-activity stability. According to the circadian entrainment hypothesis, increased access to electric lighting should lead to weaker and less uniform circadian rhythms, measured by stability of rest-activity patterns. Here, we investigate sleep in a Maya community in Guatemala who are in a transitional stage of industria
View details →DOI: 10.1371/journal.pone.0277416 Negative / Null Result ReportOpen accessScience (General)
Afsoon Motallebi, Mehdi Fathi, Fatemeh Mazhari et al. · 2024 · Heliyon
Background: This randomized clinical trial (RCT) investigated whether hypnosis would lead to favorable outcomes in reducing anxiety, enhancing cooperation, and improving physiological responses in school-aged children undergoing tooth extraction compared to nitrous oxide/oxygen (N2O/O2) and conventional behavior guidance (CBG). Methods: Sixty-six school-aged children (mean age: 7.87 ± 1.18 years) who needed one posterior primary tooth extraction were included. Children with low-to-moderate anxiety were randomly divided into three groups (n = 22 each): hypnosis, N2O/O2, and CBG. Anxiety levels
View details →DOI: 10.1016/j.heliyon.2024.e35223 Negative / Null Result ReportOpen accessGeriatrics
Sun Ju Chang, Kyoung-eun Lee, Eunjin Yang et al. · 2022 · BMC Geriatrics
Abstract Background The Internet is considered an important channel for providing health information to older adults. We developed an intervention to improve eHealth literacy in older adults according to the information-motivation-behavioral skills (IMB) theory and Intervention Mapping. This study aimed to analyze the effect of a developed intervention on information, motivation, behavioral skills, and behaviors related to eHealth information in older adults. Methods Forty-six older adults over the age of 65 were recruited from two senior welfare centers in a city in South Korea. We divided th
View details →DOI: 10.1186/s12877-022-03545-y Negative / Null Result ReportOpen accessDentistry
Gustavo Vicentis De Oliveira Fernandes, Nuno Bernardo Malta Santos, Rafael Amorim Cavalcanti De Siqueira et al. · 2021 · Journal of Indian Society of Periodontology
Background: Autologous platelet concentrate (APC)/platelet-rich fibrin (PRF) of second and third generations has increased use in periodontics to optimize wound healing. Few systematic reviews (SRs) have reported improved clinical outcomes, while other studies reported significantly better results for the connective tissue graft (CTG). There is still unclear clinical evidence about APC/PRF use to treat gingival recession (GR) defects. Then, the purpose of this SR was to evaluate the use of APC/PRF membranes (2nd and 3rd generations) in root coverage (RC) procedures and assess its efficacy as a
View details →DOI: 10.4103/jisp.jisp_515_20 Negative / Null Result ReportOpen accessDentistry
Nader Abolfazli, Masoumeh Faramarzi, Fariba Salehsaber et al. · 2018 · Journal of Advanced Periodontology and Implant Dentistry
Background. Acentric double pedicle graft is an alternative to double pedicle graft, which can improve clinical outcomes by removing tension in sutures. This study examined the effect of using platelet-rich fibrin (PRF) on the success rate of acentric double pedicle graft in treating patients with Miller Class I and II recessions. Methods. A total of 16 Miller Class I and II lesions were studied in 8 patients. The samples were divided into two groups in terms of PRF use: with PRF and without PRF. Indices, including recession depth, width of keratinized gingiva and pocket depth, were measured w
View details →DOI: 10.15171/japid.2018.010 Negative / Null Result ReportOpen accessMedicine
Can Konca, Ali Abbas Yılmaz, Süleyman Utku Çelik et al. · 2018 · Balkan Medical Journal
Background: Staple-line leak is the most frightening complication of laparoscopic sleeve gastrectomy and several predisposing factors such as using improper staple sizes regardless of gastric wall thickness, narrower bougie diameter and ischemia of the staple line are asserted. Aims: To evaluate the effects of different bougie diameters on tissue oxygen partial pressure at the esophagogastric junction after sleeve gastrectomy. Study Design: A randomized and controlled animal experiment with 1:1:1:1 allocation ratio. Methods: Thirty-two male Wistar Albino rats were randomly divided into 4 group
View details →DOI: 10.4274/balkanmedj.2017.0484 Negative / Null Result ReportOpen accessMedicine (General)
Salla Atkins, Tiia Reho, Nina Talola et al. · 2020 · Trials
Abstract Background Prolonging working careers is a key policy goal in ageing populations in Europe, but reaching this goal is complex. Occupational health services are in the best position to contribute towards prolonging working careers through preventing illnesses that cause work disability and early retirement. However, impacting on the trajectory between illness and work disability requires continuity of care and follow up, enabled through identifying patients at risk. We aimed to determine whether a combined educational and electronic reminder system in occupational health care could imp
View details →DOI: 10.1186/s13063-020-4168-8 Negative / Null Result ReportOpen accessTherapeutics. Pharmacology
Shaheen Akhtar, Sanjeev Verma, Navinder Pal Singh et al. · 2023 · National Journal of Physiology, Pharmacy and Pharmacology
Background: With improvement in living conditions in the population and the availability of treatments for various communicable and non-communicable diseases, the life expectancy and consequently the elderly population have increased. Stress leads to mental and physical problems. Aim and Objective: The aim of this study was to assess the effect of stress on muscle functions in the elderly. Materials and Methods: One hundred apparently healthy persons (50 males and 50 females) took part in the study. Perceived stress scale was used to measure their level of stress. Maximum voluntary contraction
View details →DOI: 10.5455/njppp.2023.13.11517202219122022 Negative / Null Result ReportOpen accessPublic aspects of medicine
Ahmed M. Aman Allah, Waad M. Malibarey, Sarah S. Bin Baz et al. · 2025 · The Saudi Journal of Health Systems Research
Introduction: Telehealth is a potential method for improving the quality of care for people diagnosed with type 2 diabetes (T2D). In Saudi Arabia, there is limited research on the effectiveness of telehealth for glycemic control compared to usual care. Thus, the aim of the current study was to determine the impact of telehealth on glycemic control in individuals diagnosed with T2D, with a specific focus on the examination of hemoglobin A1c (HbA1c) values. Methods: A retrospective case-control cohort study was conducted between January and August 2024 on people diagnosed with T2D who were manag
View details →DOI: 10.1159/000544061 Negative / Null Result ReportOpen accessSports medicine
Mario Hevesi MD, PhD, Alexander M. Boos, Allen Wang et al. · 2024 · Orthopaedic Journal of Sports Medicine
Objectives: Medial meniscus posterior root tears (MMPRTs) render the meniscus essentially non-functional, resulting in increased peak contact pressures, reduced forced dissipation, and increased risk of early osteoarthritis. Transtibial root repair has shown promise at restoring meniscus function and improving clinical outcomes; however, a paucity of literature exists evaluating the prognostic clinical and radiographic factors for poor outcomes following isolated meniscus root repair. The purpose of this study was to 1) describe the patient reported clinical outcomes after isolated MMPRT repai
View details →DOI: 10.1177/2325967124s00200 Negative / Null Result ReportOpen accessOrthopedic surgery
Taeko Fukuda, Shinobu Imai, Shunji Simoda et al. · 2020 · Journal of Orthopaedic Surgery
Purpose: It is unclear whether perioperative analgesic techniques affect the functional outcome of total knee replacement (TKR). We investigated the effects of peripheral nerve block (PNB) and local infiltration (LI) on walking ability after TKR. Methods: The medical records of 7143 patients who underwent TKR using general anesthesia with PNB or LI techniques were reviewed. Factors affecting independence and/or improvement of walking after surgery were investigated using multivariate regression analysis. To adjust for baseline differences and minimize selection bias for the chosen analgesic te
View details →DOI: 10.1177/2309499020931656 Negative / Null Result ReportOpen accessOrthopedic surgery
Akhil A. Chandra, Filippo Romanelli, Alex Tang et al. · 2022 · Knee Surgery & Related Research
Abstract Background Flap reconstruction with perforator, fasciocutaneous, muscular, and/or free microvascular flaps is utilized to cover wound defects and improve vascularization and antibiotic/nutrient delivery. Flap use in revision procedures for total knee arthroplasty has been explored previously; however, current data are limited and studies comparing healing and complication rates between different flap types are lacking. Methods A literature review was performed using PubMed on 13 January 2022. Studies were included if they reported healing and complication rates for either gastrocnemiu
View details →DOI: 10.1186/s43019-022-00145-3 Negative / Null Result ReportOpen accessMedical technology
Carlo Calabrese, Carlo Calabrese, Dania Gelli et al. · 2022 · Frontiers in Medical Technology
BackgroundCrohn's disease (CD) is a potentially debilitating condition that burdens Italian healthcare substantially. The symptomatic management relies on prompt therapy adjustment to reduce flares and follow-up diagnostic inputs to maximise remission. Capsule endoscopy (CE) has introduced advantages in CD diagnostics, allowing the direct inspection of the entire gastrointestinal mucosa. The diagnostic procedure is comparable in effort to standard ileocolonoscopy (IC) but requires no anaesthesia. Whether CE follow-up improves clinical outcomes remains to be defined.ObjectivesTo provide a preli
View details →DOI: 10.3389/fmedt.2022.1038087 Negative / Null Result ReportOpen accessMedicine
Elham Naghshineh, Safoura Rouholamin, Zahra Derakhshandeh · 2023 · Advanced Biomedical Research
Background: Asherman syndrome is a controversial issue in obstetrics and gynecology without any consensus on its management and treatment. It is characterized by variable lesions inside the uterine cavity and also causes menstrual irregularities, infertility, and placental abnormalities. The study aimed to assess the platelet-rich plasma (PRP) effect in women with intrauterine adhesions by evaluating the improvement of the menstrual cycle and intrauterine adhesion (IUA) stage. Materials and Methods: This clinical trial study was performed on 60 women with Asherman syndrome in two groups of 30.
View details →DOI: 10.4103/abr.abr_411_21 Negative / Null Result ReportOpen access
田原, 靖昭, 西澤, 昭, 管原, 正志 et al. · 1991
Aerobic exercise class was opened and blood and physical composition were examined. Results indicated that no significant improvement on measured items was observed. Frequency of participation is suggested to be increased or class goal…
