Negative / Null Result ReportOpen accessMedicine
Richard R. Chapleau, CharLee A. Martin, Summer R. Hughes et al. · 2019 · BMC Research Notes
Abstract Objective This study sought to determine if there is an association between variants in the apolipoprotein E (ApoE) promoter regions and development of white matter hyperintensities (WMH) in military subjects who have been exposed to high altitude. In an earlier study, we found that ApoE status did not correlate with WMH development, and here we hypothesized that regulation of APOE protein expression may be protective. Results Our cohort of 92 subjects encountered altitude exposures above 25,000 feet mean sea level through their occupations as pilots or altitude chamber technicians. U
View details →DOI: 10.1186/s13104-019-4654-9 Negative / Null Result ReportOpen accessComputer Science
CLEO Collaboration, K. Edwards et al · 1997 · arXiv
We have searched for the decay of the tau lepton into seven charged particles and zero or one pi0. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) and correspond to an integrated luminosity of 4.61 fb^(-1). No evidence for a signal is found. Assuming all the charged particles are pions, we set an upper limit on the branching fraction, B(tau- -> 4pi- 3pi+ (pi0) nu_tau) < 2.4 x 10^(-6) at the 90% confidence level. This limit represents a significant improvement over the previous limit.
Negative / Null Result ReportOpen accessBiotechnology
Yu-Sin Jang, Hyeon Jeong Seong, Seong Woo Kwon et al. · 2021 · Frontiers in Bioengineering and Biotechnology
ATPase, a key enzyme involved in energy metabolism, has not yet been well studied in Clostridium acetobutylicum. Here, we knocked down the atpG gene encoding the ATPase gamma subunit in C. acetobutylicum ATCC 824 using a mobile group II intron system and analyzed the physiological characteristics of the atpG gene knockdown mutant, 824-2866KD. Properties investigated included cell growth, glucose consumption, production of major metabolites, and extracellular pH. Interestingly, in 2-L batch fermentations, 824-2866KD showed no significant difference in metabolite biosynthesis or cell growth comp
View details →DOI: 10.3389/fbioe.2021.754250 Negative / Null Result ReportOpen accessGynecology and obstetrics
Toar A Kumaat, Maria F T Loho, Eddy Suparman · 2017 · Indonesian Journal of Obstetrics and Gynecology
Objective: To assess paramedic menopausal symptoms on the inpatient unit and outpatient unit. Methods: This was a cross sectional study. Data collect by fill the questioner, the questioner fill by menopausal paramedic on Prof. Dr. R. D. Kandou Manado Hospital from October 2016 to January 2017. Data were analyzed using SPSS 22.0 for Windows. Results: Of 60 paramedics, 30 were divided to inpatient unit and the other 30 were divided to outpatient unit. By the menopause rating scale, somatic and urogenital complaint in statistical test have no significant differences. Psychology complaint with a m
View details →DOI: 10.32771/inajog.v5i4.562 Negative / Null Result ReportOpen accessMedicine
Caio Gonçalves de Souza, Márcio Passini Gonçalves de Souza, Vanda Jorgetti et al. · 2015 · Acta Ortopédica Brasileira
OBJECTIVE: To determine whether there is a difference on the bone architecture in patients with femoral neck fracture compared to patients with intertrochanteric fractures and assess the importance of aging on bone microarchitecture in patients with proximal femoral fracture.METHODS: Biopsy of the iliac crest was made in seventeen patients between 55 and 90 years old who were admitted to the emergency room with fractures of the proximal end of the femur. After a small fragment was removed, we made a histomorphometric analysis of it.RESULTS: There was no significant difference between patients
View details →DOI: 10.1590/1413-78522015230201056 Negative / Null Result ReportMedicine
Shaygantabar, Dianati, Ledari et al. · 2026 · BMC pediatrics
Exclusive enteral nutrition (EEN) induces remission in children with active mild to moderate Crohn's disease (CD), while partial enteral nutrition (PEN) with a free diet have failed to be effective in these patients. The effects of CD…
View details →DOI: 10.1186/s12887-026-07067-z Negative / Null Result ReportOpen accessMedicine
Le J, Patel M, Atschinow A et al. · 2026 · Cureus
The platelet-rich plasma in achilles tendon healing 2 (PATH-2) trial is the largest randomized study of platelet-rich plasma (PRP) in acute Achilles tendon rupture. While the original frequentist analysis showed no significant benefit,…
View details →DOI: 10.7759/cureus.102519 Negative / Null Result ReportOpen accessDiseases of the endocrine glands. Clinical endocrinology
Sung Hye Kong · 2026 · Endocrinology and Metabolism
For decades, vitamin D has been a cornerstone of preventive medicine. However, recent large-scale randomized controlled trials have failed to replicate the broad benefits previously observed in epidemiological studies, particularly with respect to fracture and fall prevention in vitamin D-replete populations. Moreover, growing evidence suggesting an increased fall risk associated with high-dose bolus administration has necessitated a re-evaluation of safety assumptions. This review synthesizes these discordant findings to propose a framework grounded in precision medicine. We explore the ‘dive
View details →DOI: 10.3803/enm.2026.2938 Negative / Null Result ReportOpen accessOphthalmology
Rini Saha, Gautam Singh Parmar, Ashok Kumar et al. · 2018 · Journal of Clinical Ophthalmology and Research
The aim of this study is to see the effect of transportation on corneoscleral buttons and to correlate them with the weight of ice used during transportation. This is a prospective cross-sectional study. A total of 119 corneas were graded using slit-lamp examination and specular microscopy before and after transportation. Groups were made based on the weight of ice used during transportation and the number of hours of storage in McCarey-Kaufman (MK) media. The overall median percentage of endothelial cell loss (ECL) was 11.33%. The median percentage of ECL was significantly more with <500 g of
View details →DOI: 10.4103/jcor.jcor_67_16 Negative / Null Result ReportMedicine
Janz C, Timpka J, Storch A et al. · 2026 · Journal of Parkinson's disease
BackgroundThe Parkinson's Disease (PD) Home Diary (HD) is a common clinical outcome measure, but studies show only fair agreement between clinical observer and patient assessments, with no significant improvement after patient…
View details →DOI: 10.1177/1877718x261461073 Negative / Null Result ReportMedicine
Choi, Gutman, Iglesia et al. · 2026 · Urogynecology (Philadelphia, Pa.)
Studies have shown that sexual function improves after surgical correction for stress urinary incontinence and pelvic organ prolapse. Current data suggest no significant difference in sexual function between transobturator and retropubic…
View details →DOI: 10.1097/spv.0000000000001888 Negative / Null Result ReportMedicine
Mazdarani, Miles · 2026 · Veterinary research communications
Cranial cruciate ligament (CCL) rupture is uncommon in cats but may cause persistent stifle instability. Previous ex vivo assessments of tibial plateau levelling osteotomy and tibial tuberosity advancement have failed to restore stability…
View details →DOI: 10.1007/s11259-026-11361-7 Negative / Null Result ReportOpen access
Bjerknes, M. · 1986
Stochastic theories of stem cell renewal are shown to predict turnover of intestinal crypts. While I found ample evidence of production of new crypts from direct in vivo studies in adult mice, I failed to find evidence of crypt loss. Thus,…
View details →DOI: 10.1016/s0006-3495(86)83751-1 Negative / Null Result ReportOpen access
Marinus H. van IJzendoorn, Marian J. Bakermans-Kranenburg · 2009
AbstractIn middle childhood, boys show more avoidant attachments and girls more ambivalent attachments as a prelude to gender differentiation in reproductive strategies. However, we have failed to find systematic and method-independent…
View details →DOI: 10.1017/s0140525x0900003x Negative / Null Result ReportOpen accessScience
I. Yahaya, Y. Ndatsu, A. Yunusa et al. · 2023 · Journal of Applied Sciences and Environmental Management
Proximate, electrolyte and biochemical profile of rabbits fed with Tridax residue meal replacing Vitamin and Mineral were evaluated in Lapai, Niger State, Nigeria using standard techniques. The dietary treatments evaluated were 20%, 40%, 60%, 80% and 0% inclusion level of Tridax. The results obtained did not follow any pattern except Urea, Globulin and Creatinine which had significant (P<0.05) decrease in the serum biochemical profile. The highest value for crude fat was seen in feed3 with value of 11.33±0.30 and the lowest was recorded in the control feed with value of 10.38±0.21. There was n
View details →DOI: 10.4314/jasem.v27i2.24 Negative / Null Result ReportOpen accessNutrition. Foods and food supply
Arin Wulansari, Fryta Ameilia Luthfinnisa, Fuadah Uyun et al. · 2020 · Jurnal Gizi Indonesia: The Indonesian Journal of Nutrition
Background: Obesity cause various physiological changes in the body, one of which is insulin resistance causes high blood glucose levels. Chewing is a stimulus of cephalic phase responses and sensory stimulation that can increase hormones releasing such as insulin, ghrelin, cholecystokinin (CCK) and glucagon like peptide-1 (GLP-1). Chewing plays important role in determining postprandial plasma glucose concentration. Objective: Investigate the effect of chewing on postprandial blood glucose in obese adults. Method: This was true experimental research. Research subjects were treated in the form
View details →DOI: 10.14710/jgi.8.1.24-30 Negative / Null Result ReportOpen accessChemistry
Yu Jia, Cao Yu, Song Hang et al. · 2012 · Journal of the Serbian Chemical Society
Ab initio Hartree-Fock (HF) method and Density Functional Theory (DFT) were used to calculate the optical rotation of 26 chiral compounds. The effects of theory and basis sets used for calculation, solvents influence on the geometry and values of calculated optical rotation were all discussed. The polarizable continuum model, included in the calculation, did not improve the accuracy effectively, but it was superior to γs. Optical rotation of five or sixmembered of cyclic compound has been calculated and 17 pyrrolidine or piperidine derivatives which were calculated by HF and DFT methods gave a
View details →DOI: 10.2298/jsc110905207y Negative / Null Result ReportOpen accessEcology
Sánchez-Ledesma Judith A., Águila Bernardo, Garibay-Orijel Roberto et al. · 2025 · Folia Oecologica
Using ITS1-based metabarcoding, we investigated the structure of the soil fungal communities in the central and peripheral zones of a 25-hectare pecan nut (Carya illinoinensis) orchard located in the arid region of Coahuila, Mexico. While environmental conditions such as soil moisture and temperature varied between zones, physicochemical soil properties (pH, organic carbon, total carbon, organic matter, electrical conductivity, and zinc) remained homogeneous. A total of 4,443 fungal OTUs were detected at 97% similarity. Alpha diversity indices did not differ significantly between zones. The fu
View details →DOI: 10.2478/foecol-2025-0015 Negative / Null Result ReportOpen accessMedicine
Wang D, Nanavati C, Yang DZ et al. · 2026 · Journal of clinical pharmacology
Impact of concomitant medications (conmeds) on the safety of the investigational agent is often evaluated using subgroup analyses for safety events in patients who received the conmed versus those who did not. Here, we highlight the…
View details →DOI: 10.1002/jcph.70201 Negative / Null Result Report
Eggeling-Böcker M, Karabetsos E, Christopoulou M et al. · 2025 · Preprint
Background: Technological advancements, such as the introduction of the fifth generation technology standard 5G, offer opportunities but also raise concerns. Although no evidence suggests negative effects of radiofrequency electromagnetic…
View details →DOI: 10.12688/openreseurope.19236.2 Negative / Null Result ReportOpen accessDiseases of the circulatory (Cardiovascular) system
Oh Young Bang, Mi Ji Lee, Sookyung Ryoo et al. · 2015 · Journal of Stroke
Patent foramen ovale (PFO) is growing in clinical interest because of a renewed focus on embolic stroke of undetermined source (ESUS), the PFO attributable fraction (the 10-point Risk of Paradoxical Embolism score), technical advances in PFO diagnosis, and the emergence of endovascular device closure as a treatment option. However, recent randomized controlled trials of the management of patients with ESUS and PFO failed to demonstrate the superiority of closure over medical treatment. The mechanisms of stroke other than paradoxical embolism may be important in patients with ESUS and PFO. This
View details →DOI: 10.5853/jos.2015.17.3.229 Negative / Null Result ReportMedicine
Shah R, Das S, Gentile Kruse CF et al. · 2025 · Pediatric neurology
Background Triptans are used to treat migraine attacks, but little to no evidence supports their use for youth with post-traumatic headache (PTH). This study evaluated patterns of use and benefit of triptans in the treatment of acute…
View details →DOI: 10.1016/j.pediatrneurol.2025.03.013 Negative / Null Result ReportMedicine
Marder SR, Eriksson H, Zhao Y et al. · 2020 · Acta neuropsychiatrica
Objective We provide a closer look at the result of a randomised, placebo-controlled, active-reference (quetiapine XR), flexible-dose, 6-week study of brexpiprazole in schizophrenia, which did not meet its primary endpoint - change from…
View details →DOI: 10.1017/neu.2020.8 Negative / Null Result ReportMedicine
Campo-Beamud C, Roig-Ferreruela G · 2026 · Archivos de la Sociedad Espanola de Oftalmologia
Blue light is a physiological component of visible light, essential for daytime vision and circadian synchronization. There is no evidence supporting the routine use of blue-blocking glasses for preventive or therapeutic purposes. The most…
View details →DOI: 10.1016/j.oftale.2026.502590 Negative / Null Result ReportOpen accessMedicine
Saqib K, Goel V, Dubin JA et al. · 2026 · International journal of public health
Objective To examine differences in mental health-related healthcare utilization for anxiety and depression between individuals who did and did not undergo COVID-19 PCR testing in Ontario. Background: The COVID-19 pandemic has been…
View details →DOI: 10.3389/ijph.2026.1609134 Negative / Null Result ReportMedicine
Galipienso-Eri M, Baraldés-Canals M, Aliaga-Martínez A et al. · 2025 · Indian journal of orthopaedics
Background/purpose Periprosthetic joint infection (PJI) accounts for up to 25% of failed total knee arthroplasties and 15% of the hips. The ICM18 established the criteria for the diagnosis, and the alpha-defensin lateral flow test (ADLT)…
View details →DOI: 10.1007/s43465-025-01409-2 Negative / Null Result ReportOpen accessMedicine
Bath PM, Howard G, Hacke W · 2025 · Neurological research and practice
Background The majority of randomised controlled trials in acute stroke and many for prevention are neutral, i.e. they failed to reach statistical significance. However, many of these will find apparent benefit in a component of a…
View details →DOI: 10.1186/s42466-025-00369-0 Negative / Null Result ReportOpen accessMedicine
Sameed M, Meng Z, Marciniak ET · 2019 · Breathe (Sheffield, England)
In the EOLIA trial, early use of ECMO did not significantly improve mortality at 60 days in patients with severe ARDS, but when used as a rescue modality ECMO might help improve survival http://bit.ly/2XOjwSE.
View details →DOI: 10.1183/20734735.0363-2018 Negative / Null Result ReportOpen accessAnimal culture
Samadi F, Sahneh M · 2015 · Poultry Science Journal
A total of 240, one-day-old quail chicks (Coturnix coturnix japonica) were used to study the effects of Artichoke leaf meal (ALM) and vitamin E in diet on growth performance, ileal microbial populations and intestinal morphology in a 42-d trial. This experiment was performed as a completely randomized design with 4 replicates of 15 quails each, using a 4 × 2 factorial arrangement with diet and gender as the main effects. Four dietary treatments were formulated by addition of 2 levels (1.5 and 3 percent) of ALM and 300 mg/Kg vitamin E to the basal diet. Supplementing basal diet with ALM did not
Negative / Null Result Report
Furne Gouveia G · 2026 · Preprint
The Michelson–Morley experiment yielded a null result, indicating equal light travel times in the longitudinal and transverse arms of an interferometer, traditionally interpreted as evidence against a light-propagating medium. This paper…
View details →DOI: 10.20944/preprints202601.0623.v1 