Scanning electron microscopic analysis of 5% glycolic acid as a novel alternative to 17% ethylenediaminetetraacetic acid in root biomodification: An in vitro study.

Background: Nonsurgical periodontal therapy results in the formation of a smear layer which inhibits tissue regeneration. Root biomodification (RB) using various agents has been tried for the enhancement of new attachment formation. However, no substantial therapeutic advantages of currently available root conditioning agents have been reported emphasizing the need for additional biologically acceptable agents. Glycolic acid (GA) due to its antimicrobial nature and ability of initiation and proliferation of fibroblasts may potentially modify root surface enabling regeneration. Materials and Methods: Eighty specimens from 40 single-rooted teeth were treated with 17% ethylenediaminetetraacetic acid (EDTA) and 5% GA and scanning electron microscopy analysis was done. The micrographs were examined for the evaluation of smear layer removal, total number of dentinal tubules, total number of patent dentinal tubules, mean diameter and surface area of dentinal tubules, and dentin erosion. Statistical analysis was done using unpaired t-test for intergroup comparison. Results: The efficacy of smear layer removal (P = 0.01) and dentin erosion (P = 0.042) was significantly better in the GA group. Both the groups showed no difference in dentinal tubule-related parameters. Conclusion: GA showed improved RB with greater smear layer removal and lesser dentin erosion, indicating its use as a potent alternative to the conventional EDTA root conditioning.

High-throughput quantification of quasistatic, dynamic and spall strength of materials across 10 orders of strain rates.

The response of metals and their microstructures under extreme dynamic conditions can be markedly different from that under quasistatic conditions. Traditionally, high strain rates and shock stresses are achieved using cumbersome and expensive methods such as the Kolsky bar or large spall experiments. These methods are low throughput and do not facilitate high-fidelity microstructure-property linkages. In this work, we combine two powerful small-scale testing methods, custom nanoindentation, and laser-driven microflyer (LDMF) shock, to measure the dynamic and spall strength of metals. The nanoindentation system is configured to test samples from quasistatic to dynamic strain-rate regimes. The LDMF shock system can test samples through impact loading, triggering spall failure. The model material used for testing is magnesium alloys, which are lightweight, possess high-specific strengths, and have historically been challenging to design and strengthen due to their mechanical anisotropy. We adopt two distinct microstructures, solutionized (no precipitates) and peak-aged (with precipitates) to demonstrate interesting upticks in strain-rate sensitivity and evolution of dynamic strength. At high shock-loading rates, we unravel an interesting paradigm where the spall strength vs. strain rate of these materials converges, but the failure mechanisms are markedly different. Peak aging, considered to be a standard method to strengthen metallic alloys, causes catastrophic failure, faring much worse than solutionized alloys. Our high-throughput testing framework not only quantifies strength but also teases out unexplored failure mechanisms at extreme strain rates, providing valuable insights for the rapid design and improvement of materials for extreme environments.

Retrospective analysis of neoplasms in patients using angiotensin receptor blockers.

In recent years, regulatory agencies have raised concerns about the presence of potentially carcinogenic substances in certain formulations of Angiotensin Receptor Blockers (ARBs). Specifically, nitrosamines and azido compounds have been identified in some ARB products. Nitrosamines are known to have carcinogenic properties and are associated with an increased risk of neoplasms. Spontaneous safety reports from the EudraVigilance Data Analysis System (EVDAS) database were analyzed to investigate cases of neoplasms associated with ARBs. A disproportionality analysis was conducted, calculating the reporting odds ratio (ROR) and 95% confidence intervals (CIs) using a case/non-case approach for each ARB drug. The EVDAS database contained 68,522 safety reports related to ARBs (including Azilsartan, Candesartan, Irbesartan, Olmesartan, Losartan, Valsartan, and Telmisartan), among which 3,396 (5%) cases were associated with neoplasms. The majority of these cases were reported in Germany (11.9%), followed by France (9.7%). Approximately 70% of the reports were submitted by healthcare professionals such as physicians and nurses. Among the ARBs, valsartan had the highest ROR for neoplasm (ROR 1.949, 95% CI 1.857-2.046). This association remained significant when comparing ARBs with other classes of antihypertensive drugs, including ACE inhibitors, beta-blockers, calcium channel blockers, and diuretics. Our study identifies a possible signal of an association between ARBs, particularly valsartan, and the risk of neoplasms. However, further observational and analytical studies are necessary to confirm these findings and elucidate the underlying mechanisms.

Neoadjuvant T-DM1 for HER2-positive breast cancer used as a bridging strategy during COVID-19 pandemic: lessons learned-a case series.

Background: Coronavirus disease 19 (COVID-19) has played a pivotal role in changing medical care around the world. During the pandemic, the operating rooms (ORs) were closed to elective surgery. Since breast cancer surgery is not regarded as an emergent procedure, there was an adoption of treatment regimen modification due to delays in treatment. Therefore, a decision was made to bridge early-stage HER2-positive breast cancer patients with neoadjuvant treatment to postpone surgery. Consequently, to reduce the frequency of dosing and the number of visits, as well as avoid steroid premedication, these patients were treated with ado-trastuzumab emtansine (T-DM1) every three weeks as opposed to weekly taxol and herceptin (TH). Case Description: Five patients with early-stage HER2-positive cancer were treated with neoadjuvant T-DM1 3.6 mg/kg IV every three weeks. Three of the five patients developed cancer progression identified by their physical exam and/or imaging. T-DM1 was discontinued, and all three patients underwent immediate surgery. The remaining two patients, 4 and 5, had a complete and partial pathological response, respectively. All five patients received adjuvant therapy after surgery, and currently, none of these patients show evidence of disease on follow-up. Conclusions: Our findings underscore the obstacles and treatment challenges encountered during the COVID-19 pandemic while preventing the spread of the virus and cancer progression. Furthermore, the use of T-DM1 for neoadjuvant treatment remains controversial, particularly when T-DM1 is used as a bridge to surgery during critical times. Perhaps better patient selection or a different drug regimen could have resulted in a better outcome in our study.

Consensus-Based Guidelines for Acute Myeloid Leukemia Management in Gulf Cooperation Council Countries: Addressing Unmet Regional Needs and the Changing AML Landscape.

PURPOSE: AML is a heterogeneous hematologic malignancy. Region-specific recommendations for AML management can enhance patient outcomes. This article aimed to develop recommendations for the Gulf Cooperation Council (GCC) countries. METHODS: Ten AML panel members from Kuwait, Oman, Qatar, and the United Arab Emirates (KOQU) participated in a modified two-round Delphi process. The panel first identified the unmet regional needs and finalized a list of core variables. Next, they voted on iterative statements drawn from international recommendations and provided feedback via a questionnaire. Consensus voting ≤70% was discussed, and additional clinical decision making statements were suggested. At round closure, a consensus vote took place on revised statements. RESULTS: The panel reached ≥97.8% consensus on AML management. The panel agreed to use international risk stratification categories for personalized treatment of AML. The presence of ≥10% blasts for recurrent genetic abnormalities was required for a diagnosis of AML. Key consensus was reached for different treatment stages. The panel noted that older patients pose a challenge because of poor cytogenetics and genetic anomalies and require different treatment approaches. The panel recommended venetoclax-hypomethylating agents; fludarabine, cytarabine, idarubicin, and granulocyte colony-stimulating factor; and targeted therapy for AML relapsed/refractory disease. Supportive care is considered on the basis of prevailing organisms and drug resistance. CONCLUSION: The GCC KOQU's consensus-based recommendations for managing AML include an evidence-based and region-specific framework.

Supported-amine-catalyzed cascade synthesis of spiro-thiazolone-tetrahydrothiophenes: assessing HSA binding activity.

We have devised a supported-amine-catalyzed efficient synthesis of spiro-thiazolone-tetrahydrothiophenes via a sulfa-Michael/aldol cascade approach. The catalyst demonstrated sustained efficacy over 21 cycles. These derivatives were found to exhibit excellent binding abilities with purified human serum albumin as indicated by both in silico and in vitro-based experiments.

Parallel Interactions Between Linguistic and Contextual Factors in Bilinguals.

The necessity for introducing interactionist and parallelism approaches in different branches of cognitive science emerged as a reaction to classical sequential stage-based models. Functional psychological models that emphasized and explained how different components interact, dynamically producing cognitive and perceptual states, influenced multiple disciplines. Chiefly among them were experimental psycholinguistics and the many applied areas that dealt with humans' ability to process different types of information in different contexts. Understanding how bilinguals represent and process verbal and visual input, how their neural and psychological states facilitate such interactions, and how linguistic and nonlinguistic processing overlap, has now emerged as an important area of multidisciplinary research. In this article, we will review available evidence from different language-speaking groups of bilinguals in India with a focus on situational context. In the discussion, we will address models of language processing in bilinguals within a cognitive psychological approach with a focus on existent models of inhibitory control. The paper's stated goal will be to show that the parallel architecture framework can serve as a theoretical foundation for examining bilingual language processing and its interface with external factors such as social context.

Biosensors for the detection of chorismate and cis, cis-muconic acid in Corynebacterium glutamicum.

Corynebacterium glutamicum ATCC 13032 is a promising microbial chassis for industrial production of valuable compounds, including aromatic amino acids derived from the shikimate pathway. In this work, we developed two whole-cell, transcription factor based fluorescent biosensors to track cis, cis-muconic acid (ccMA) and chorismate in C. glutamicum. Chorismate is a key intermediate in the shikimate pathway from which value-added chemicals can be produced, and a shunt from the shikimate pathway can divert carbon to ccMA, a high value chemical. We transferred a ccMA-inducible transcription factor, CatM, from Acinetobacter baylyi ADP1 into C. glutamicum and screened a promoter library to isolate variants with high sensitivity and dynamic range to ccMA by providing benzoate, which is converted to ccMA intracellularly. The biosensor also detected exogenously supplied ccMA, suggesting the presence of a putative ccMA transporter in C. glutamicum, though the external ccMA concentration threshold to elicit a response was 100-fold higher than the concentration of benzoate required to do so through intracellular ccMA production. We then developed a chorismate biosensor, in which a chorismate inducible promoter regulated by natively expressed QsuR was optimized to exhibit a dose-dependent response to exogenously supplemented quinate (a chorismate precursor). A chorismate-pyruvate lyase encoding gene, ubiC, was introduced into C. glutamicum to lower the intracellular chorismate pool, which resulted in loss of dose-dependence to quinate. Further, a knockout strain that blocked the conversion of quinate to chorismate, also resulted in absence of dose-dependence to quinate, validating that the chorismate biosensor is specific to intracellular chorismate pool. The ccMA and chorismate biosensors were dually inserted into C. glutamicum to simultaneously detect intracellularly produced chorismate and ccMA. Biosensors, such as those developed in this study, can be applied in C. glutamicum for multiplex sensing to expedite pathway design and optimization through metabolic engineering in this promising chassis organism.

Identification of Cinnamein, a Component of Balsam of Tolu/Peru, as a New Ligand of PPARα for Plaque Reduction and Memory Protection in a Mouse Model of Alzheimer's Disease.

Background: Despite intense investigations, no effective treatment is yet available to reduce plaques and protect memory and learning in patients with Alzheimer's disease (AD), the most common neurodegenerative disorder. Therefore, it is important to identify a non-toxic, but effective, treatment option for AD. Objective: Cinnamein, a nontoxic compound, is naturally available in Balsam of Peru and Tolu Balsam. We examined whether cinnamein treatment could decrease plaques and improve cognitive functions in 5XFAD mouse model of AD. Methods: We employed in silico analysis, time-resolved fluorescence energy transfer assay, thermal shift assay, primary neuron isolation, western blot, immunostaining, immunohistochemistry, Barnes maze, T maze, and open field behavior. Results: Oral administration of cinnamein led to significant reduction in amyloid-ß plaque deposits in the brain and protection of spatial learning and memory in 5XFAD mice. Peroxisome proliferator-activated receptor alpha (PPARα), a nuclear hormone receptor, is involved in plaque lowering and increase in hippocampal plasticity. While investigating underlying mechanisms, we found that cinnamein served as a ligand of PPARα. Accordingly, oral cinnamein upregulated the level of PPARα, but not PPARß, in the hippocampus, and remained unable to decrease plaques from the hippocampus and improve memory and learning in 5XFAD mice lacking PPARα. While A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) is one of the drivers of nonamyloidogenic pathway, transcription factor EB (TFEB) is considered as the master regulator of autophagy. Cinnamein treatment was found to upregulate both ADAM10 and TFEB in the brain of 5XFAD mice via PPARα. Conclusions: Our results suggest that this balsam component may have therapeutic importance in AD.

An Adjustable Pneumatic Planter with Reduced Source Vibration for Better Precision in Field Seeding.

The growing demand for agricultural output and limited resources encourage precision applications to generate higher-order output by utilizing minimal inputs of seed, fertilizer, land, and water. An electronically operated planter was developed, considering problems like ground-wheel skidding, field vibration, and the lack of ease in field adjustments of ground-wheel-driven seed-metering plates. The seed-metering plate of each unit of the developed planter is individually driven by a brushless direct current (BLDC) motor, and a BLDC motor-based aspirator is attached for pneumatic suction of seeds. The revolutions per minute (RPM) of the seed-metering plate are controlled by a microcontroller as per the received data relating to RPM from the ground wheel and the current RPM of the seed-metering plate. A feedback loop with proportional integral derivative (PID) control is responsible for reducing the error. Additionally, each row unit is attached to a parallelogram-based depth control system that can provide depth between 0 and 100 mm. The suction pressure in each unit is regulated as per seed type using the RPM control knob of an individual BLDC motor-based aspirator. The row-to-row spacing can be changed from 350 mm to any desired spacing. The cotton variety selected for the study was RCH 659, and the crucial parameters like orifice size, vacuum pressure, and forward speed were optimized in the laboratory with the adoption of a central composite rotatable design. An orifice diameter of 2.947 mm with vacuum pressure of 3.961 kPa and forward speed of 4.261 km/h was found optimal. A quality feed index of 93% with a precision index of 8.01% was observed from laboratory tests under optimized conditions. Quality feed index and precision index values of 88.8 and 12.75%, respectively, were obtained from field tests under optimized conditions.

A study of antibiotic resistance pattern of clinical bacterial pathogens isolated from patients in a tertiary care hospital.

We investigated antibiotic resistance pattern in clinical bacterial pathogens isolated from in-patients and out-patients, and compared it with non-clinical bacterial isolates. 475 bacterial strains isolated from patients were examined for antibiotic resistance. Staphylococcus spp. (148; 31.1%) were found to be the most prevalent, followed by Klebsiella pneumoniae (135; 28.4%), Escherichia coli (74; 15.5%), Pseudomonas aeruginosa (65; 13.6%), Enterobacter spp. (28; 5.8%), and Acinetobacter spp. (25; 5.2%). Drug-resistant bacteria isolated were extended spectrum-ß-lactamase K. pneumoniae (8.8%), E. coli (20%), metallo-ß-lactamase P. aeruginosa (14; 2.9%), erythromycin-inducing clindamycin resistant (7.4%), and methicillin-resistant Staphylococcus species (21.6%). Pathogens belonging to the Enterobacteriaceae family were observed to undergo directional selection developing resistance against antibiotics ciprofloxacin, piperacillin-tazobactam, cefepime, and cefuroxime. Pathogens in the surgical ward exhibited higher levels of antibiotic resistance, while non-clinical P. aeruginosa and K. pneumoniae strains were more antibiotic-susceptible. Our research assisted in identifying the drugs that can be used to control infections caused by antimicrobial resistant bacteria in the population and in monitoring the prevalence of drug-resistant bacterial pathogens.

Designing a Phenalenyl-Based Dinuclear Ni(II) Complex: An Electrocatalyst with Two Single Ni Sites for the Oxygen Evolution Reaction (OER).

A new dinuclear Ni(II) complex 1, [Ni2II(dtbh-PLY)2], is synthesized from 9-(2-(3,6-di-tert-butyl-2-hydroxybenzylidene)hydrazineyl)-1H-phenalen-1-one, dtbh-PLYH2 ligand, and structurally characterized by various analytical tools including the single-crystal X-ray diffraction (SCXRD) technique. In the solid state, both Ni(II) metal centers in complex 1 exist in a distorted square planar geometry and display the presence of rare Ni···H-C anagostic interactions to form a one-dimensional (1-D) linear motif in the supramolecular array. Complex 1 is further stabilized in the solid state by π-π-stacking interactions between the highly delocalized phenalenyl rings. The redox features of complex 1 have been analyzed by the cyclic voltammetry (CV) technique in solution as well as in the solid state, revealing the crucial involvement of both the Ni(II) metal centers for undergoing quasi-reversible oxidation reactions on the application of an anodic sweep. A complex 1-modified glassy carbon electrode, GC-1, is employed as an electrocatalyst for oxygen evolution reaction (OER) in 1.0 M KOH, giving an OER onset at 1.45 V, and very low OER overpotential, 300 mV vs the reversible hydrogen electrode (RHE) to reach 10 mA cm-2 current density. Furthermore, GC-1 displayed fast OER kinetics with a Tafel slope of 40 mV dec-1, a significantly lower Tafel slope value than those of previously reported molecular Ni(II) catalysts. In situ electrochemical experiments and postoperational UV-vis, Fourier transform infrared (FT-IR), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) studies were performed to analyze the stability of the molecular nature of complex 1 and to gain reasonable insights into the true OER catalyst.

MicroRNAs: exploring their role in farm animal disease and mycotoxin challenges.

MicroRNAs (miRNAs) serve as key regulators in gene expression and play a crucial role in immune responses, holding a significant promise for diagnosing and managing diseases in farm animals. This review article summarizes current research on the role of miRNAs in various farm animal diseases and mycotoxicosis, highlighting their potential as biomarkers and using them for mitigation strategies. Through an extensive literature review, we focused on the impact of miRNAs in the pathogenesis of several farm animal diseases, including viral and bacterial infections and mycotoxicosis. They regulate gene expression by inducing mRNA deadenylation, decay, or translational inhibition, significantly impacting cellular processes and protein synthesis. The research revealed specific miRNAs associated with the diseases; for instance, gga-miR-M4 is crucial in Marek's disease, and gga-miR-375 tumor-suppressing function in Avian Leukosis. In swine disease such as Porcine Respiratory and Reproductive Syndrome (PRRS) and swine influenza, miRNAs like miR-155 and miR-21-3p emerged as key regulatory factors. Additionally, our review highlighted the interaction between miRNAs and mycotoxins, suggesting miRNAs can be used as a biomarker for mycotoxin exposure. For example, alterations in miRNA expression, such as the dysregulation observed in response to Aflatoxin B1 (AFB1) in chickens, may indicate potential mechanisms for toxin-induced changes in lipid metabolism leading to liver damage. Our findings highlight miRNAs potential for early disease detection and intervention in farm animal disease management, potentially reducing significant economic losses in agriculture. With only a fraction of miRNAs functionally characterized in farm animals, this review underlines more focused research on specific miRNAs altered in distinct diseases, using advanced technologies like CRISPR-Cas9 screening, single-cell sequencing, and integrated multi-omics approaches. Identifying specific miRNA targets offers a novel pathway for early disease detection and the development of mitigation strategies against mycotoxin exposure in farm animals.

Metagenomic evaluation of peanut rhizosphere microbiome from the farms of Saurashtra regions of Gujarat, India.

The narrow zone of soil around the plant roots with maximum microbial activity termed as rhizosphere. Rhizospheric bacteria promote the plant growth directly or indirectly by providing the nutrients and producing antimicrobial compounds. In this study, the rhizospheric microbiota of peanut plants was characterized from different farms using an Illumina-based partial 16S rRNA gene sequencing to evaluate microbial diversity and identify the core microbiome through culture-independent (CI) approach. Further, all rhizospheric bacteria that could grow on various nutrient media were identified, and the diversity of those microbes through culture-dependent method (CD) was then directly compared with their CI counterparts. The microbial population profiles showed a significant correlation with organic carbon and concentration of phosphate, manganese, and potassium in the rhizospheric soil. Genera like Sphingomicrobium, Actinoplanes, Aureimonas _A, Chryseobacterium, members from Sphingomonadaceae, Burkholderiaceae, Pseudomonadaceae, Enterobacteriaceae family, and Bacilli class were found in the core microbiome of peanut plants. As expected, the current study demonstrated more bacterial diversity in the CI method. However, a higher number of sequence variants were exclusively present in the CD approach compared to the number of sequence variants shared between both approaches. These CD-exclusive variants belonged to organisms that are more typically found in soil. Overall, this study portrayed the changes in the rhizospheric microbiota of peanuts in different rhizospheric soil and environmental conditions and gave an idea about core microbiome of peanut plant and comparative bacterial diversity identified through both approaches.

Role of MMP-9 and NF-κB in Diabetic Retinopathy: Progression and Potential Role of Bioflavonoids in the Mitigation of Diabetic Retinopathy.

"Diabetes mellitus" is a chronic metabolic disorder manifested by elevated blood glucose levels, primarily due to insufficient insulin production or resistance to insulin. Long-term diabetes results in persistent complications like retinopathy, cardiomyopathy, nephropathy, and neuropathy, causing significant health risks. The most alarming microvascular consequence allied with diabetes is "diabetic retinopathy," distinguished by the proliferation of anomalous blood vessels in the eye, mainly in the retina, resulting in visual impairment, diabetic macular edema, and retinal detachment if left untreated. According to estimates, 27.0% of people with diabetes worldwide have retinopathy, which leads to 0.4 million blindness cases. It is believed that mitochondrial damage and the production of inflammatory mediators are the early indicators of diabetic retinopathy before any histological changes occur in the retina. Moreover, it is evident that augmented oxidative stress in the retina further initiates the NF-κB/MMP-9 downstream signaling pathway. Interestingly, these downstream regulators, Nuclear Factor Kappa B [NF- kB] and matrix metalloproteinases 9 [MMP-9], have been recognized as important regulators of the inception and advancement of diabetic retinopathy. This diabetes and oxidative stress-induced MMP-9 are believed to regulate various cellular functions, including angiogenesis and apoptosis, causing blood-retinal barrier breakdown and tight junction protein degradation that further leads to diabetic retinopathy. Thus, there is an emergency need for the treatment of diabetic retinopathy. Emerging treatment options include anti-VEGF, laser treatment, and eye surgery, but these have certain limitations. This comprehensive review explores the mechanisms of MMP-9 and NF-kB involvement in diabetic retinopathy and bioflavonoids' therapeutic potential and mechanisms of action in inhibiting MMP-9 activity and suppressing NF-kB-mediated inflammation. Clinical evidence supporting the use of bioflavonoids in mitigating diabetic complications and future perspectives are also examined.

Neurogenic thoracic outlet syndrome and controversies in diagnosis and management.

Compression of the neurovascular structures at the level of the scalene triangle and pectoralis minor space is rare, but increasing awareness and understanding is allowing for the treatment of more individuals than in the past. We outlined the recognition, preoperative evaluation, and treatment of patients with neurogenic thoracic outlet syndrome. Recent work has illustrated the role of imaging and centrality of the physical examination on the diagnosis. However, a fuller understanding of the spatial biomechanics of the shoulder, scalene triangle, and pectoralis minor musculotendinous complex has shown that, although physical therapy is a mainstay of treatment, a poor response to physical therapy with a sound diagnosis should not preclude decompression. Modes of failure of surgical decompression stress the importance of full resection of the anterior scalene muscle and all posterior rib impinging elements to minimize the risk of recurrence of symptoms. Neurogenic thoracic outlet syndrome is a rare but critical cause of disability of the upper extremity. Modern understanding of the pathophysiology and evaluation have led to a sounder diagnosis. Although physical therapy is a mainstay, surgical decompression remains the gold standard to preserve and recover function of the upper extremity. Understanding these principles will be central to further developments in the treatment of this patient population.

Effect of Human Head Shape on the Risk of Traumatic Brain Injury: A Gaussian Process Regression-based Machine Learning Approach.

INTRODUCTION: Computational head injury models are promising tools for understanding and predicting traumatic brain injuries. However, most available head injury models are "average" models that employ a single set of head geometry (e.g., 50th-percentile U.S. male) without considering variability in these parameters across the human population. A significant variability of head shapes exists in U.S. Army soldiers, evident from the Anthropometric Survey of U.S. Army Personnel (ANSUR II). The objective of this study is to elucidate the effects of head shape on the predicted risk of traumatic brain injury from computational head injury models. MATERIALS AND METHODS: Magnetic resonance imaging scans of 25 human subjects are collected. These images are registered to the standard MNI152 brain atlas, and the resulting transformation matrix components (called head shape parameters) are used to quantify head shapes of the subjects. A generative machine learning model is used to generate 25 additional head shape parameter datasets to augment our database. Head injury models are developed for these head shapes, and a rapid injurious head rotation event is simulated to obtain several brain injury predictor variables (BIPVs): Peak cumulative maximum principal strain (CMPS), average CMPS, and the volume fraction of brain exceeding an injurious CMPS threshold. A Gaussian process regression model is trained between head shape parameters and BIPVs, which is then used to study the relative sensitivity of the various BIPVs on individual head shape parameters. We distinguish head shape parameters into 2 types: Scaling components ${T_{xx}}$, ${T_{yy}}$, and ${T_{zz}}$ that capture the breadth, length, and height of the head, respectively, and shearing components (${T_{xy}},{T_{xz}},{T_{yx}},{T_{yz}},{T_{zx}}$, and ${T_{zy}}$) that capture the relative skewness of the head shape. RESULTS: An overall positive correlation is evident between scaling components and BIPVs. Notably, a very high, positive correlation is seen between the BIPVs and the head volume. As an example, a 57% increase in peak CMPS was noted between the smallest and the largest investigated head volume parameters. The variation in shearing components ${T_{xy}},{T_{xz}},{T_{yx}},{T_{yz}},{T_{zx}}$, and ${T_{zy}}$ on average does not cause notable changes in the BIPVs. From the Gaussian process regression model, all 3 BIPVs showed an increasing trend with each of the 3 scaling components, but the BIPVs are found to be most sensitive to the height dimension of the head. From the Sobol sensitivity analysis, the ${T_{zz}}$ scaling parameter contributes nearly 60% to the total variance in peak and average CMPS; ${T_{yy}}$ contributes approximately 20%, whereas ${T_{xx}}$ contributes less than 5%. The remaining contribution is from the 6 shearing components. Unlike peak and average CMPS, the VF-CMPS BIPV is associated with relatively evenly distributed Sobol indices across the 3 scaling parameters. Furthermore, the contribution of shearing components on the total variance in this case is negligible. CONCLUSIONS: Head shape has a considerable influence on the injury predictions of computational head injury models. Available "average" head injury models based on a 50th-percentile U.S. male are likely associated with considerable uncertainty. In general, larger head sizes correspond to greater BIPV magnitudes, which point to potentially a greater injury risk under rapid neck rotation for people with larger heads.